Pseudo-fermion functional renormalization group for spin models

For decades, frustrated quantum magnets have been a seed for scientific progress and innovation in condensed matter. As much as the numerical tools for low-dimensional quantum magnetism have thrived and improved in recent years due to breakthroughs inspired by quantum information and quantum computation, higher-dimensional quantum magnetism can be considered as the final frontier, where strong quantum entanglement, multiple ordering channels, and manifold ways of paramagnetism culminate. At the same time, efforts in crystal synthesis have induced a significant increase in the number of tangible frustrated magnets which are generically three-dimensional in nature, creating an urgent need for quantitative theoretical modeling. We review the pseudo-fermion (PF) and pseudo-Majorana (PM) functional renormalization group (FRG) and their specific ability to address higher-dimensional frustrated quantum magnetism. First developed more than a decade ago, the PFFRG interprets a Heisenberg model Hamiltonian in terms of Abrikosov pseudofermions, which is then treated in a diagrammatic resummation scheme formulated as a renormalization group flow ofm-particle pseudofermion vertices. The article reviews the state of the art of PFFRG and PMFRG and discusses their application to exemplary domains of frustrated magnetism, but most importantly, it makes the algorithmic and implementation details of these methods accessible to everyone. By thus lowering the entry barrier to their application, we hope that this review will contribute towards establishing PFFRG and PMFRG as the numerical methods for addressing frustrated quantum magnetism in higher spatial dimensions.

Recent advances in chitosan-based materials; The synthesis, modifications and biomedical applications

The attention to polymer-based biomaterials, for instance, chitosan and its derivatives, as well as the techniques for using them in numerous scientific domains, is continuously rising. Chitosan is a decomposable naturally occurring polymeric material that is mostly obtained from seafood waste. Because of its special ecofriendly, biocompatible, non- toxic nature as well as antimicrobial properties, chitosan-based materials have received a lot of interest in the field of biomedical applications. The reactivity of chitosan is mainly because of the amino and hydroxyl groups in its composition, which makes it further fascinating for various uses, including biosensing, textile finishing, antimicrobial wound dressing, tissue engineering, bioimaging, gene, DNA and drug delivery and as a coating material for medical implants. This study is an overview of the different types of chitosan-based materials which now a days have been fabricated by applying different techniques and modifications that include etherification, esterification, crosslinking, graft copolymerization and o-acetylation etc. for hydroxyl groups' processes and acetylation, quaternization, Schiff's base reaction, and grafting for amino groups' reactions. Furthermore, this overview summarizes the literature from recent years related to the important applications of chitosan-based materials (i.e., thin films, nanocomposites or nanoparticles, sponges and hydrogels) in different biomedical applications.

Environmental MCS package and green intellectual capital influence environmental performance: a mediated-moderated perspective

Nowadays, business is not only a financial entity. The environmental impact of rapid business growth necessitates solutions. This study considers natural resource orchestration theory (ROT) to study the impact of the environment management control system (MCS) package and green intellectual capital (IC) on environmental performance through the mediating role of top management support (TMS) and the interaction role of green business strategies. This study employed partial least squares structural equation modeling to analyze 358 questionnaires. Simple sampling was used to collect data from Pakistan manufacturing firms. The results revealed that the environmental MCS package significantly influences environmental performance directly and through TMS mediation. Still, the green IC does not influence environmental performance directly or through mediation in selected industries of Pakistan. Furthermore, the interaction of TMS and green business strategies significantly determines environmental performance. This study suggests managers use the environmental MCS package, green IC, top management support, and green business strategies in decision-making to determine environmental performance of manufacturing firms in Pakistan even though green IC has no influence on environmental performance. This study used natural ROT to impart the managerial role along with bundling firms' resources and strategies (i.e., environmental MCS package, green IC, top management support, and green business strategies) which is ignored in the resource-based view.

Quantum Effects on Unconventional Pinch Point Singularities

Fracton phases are a particularly exotic type of quantum spin liquids where the elementary quasiparticles are intrinsically immobile. These phases may be described by unconventional gauge theories known as tensor or multipolar gauge theories, characteristic for so-called type-I or type-II fracton phases, respectively. Both variants have been associated with distinctive singular patterns in the spin structure factor, such as multifold pinch points for type-I and quadratic pinch points for type-II fracton phases. Here, we assess the impact of quantum fluctuations on these patterns by numerically investigating the spin S=1/2 quantum version of a classical spin model on the octahedral lattice featuring exact realizations of multifold and quadratic pinch points, as well as an unusual pinch line singularity. Based on large scale pseudofermion and pseudo-Majorana functional renormalization group calculations, we take the intactness of these spectroscopic signatures as a measure for the stability of the corresponding fracton phases. We find that in all three cases, quantum fluctuations significantly modify the shape of pinch points or lines by smearing them out and shifting signal away from the singularities in contrast to effects of pure thermal fluctuations. This indicates possible fragility of these phases and allows us to identify characteristic fingerprints of their remnants.

4-Adamantyl-(2-(arylidene)hydrazinyl)thiazoles as potential antidiabetic agents: experimental and docking studies

Aim: To develop an efficient and cost-effective antidiabetic agent. Methods: A simple and convenient Hantzsch synthetic strategy was used to prepare 4-adamantyl-(2-(arylidene)hydrazinyl)thiazoles. Results: Fifteen newly established structures of 4-adamantyl-(2-(arylidene)hydrazinyl)thiazoles were tested for their α-amylase, antiglycation and antioxidant activities. Almost all tested compounds showed excellent α-amylase inhibition. Compounds 3a and 3j exhibited the highest potency, with IC₅₀ values of 16.34 ± 2.67 and 16.64 ± 1.12 μM, respectively. Compounds 3c and 3i exhibited comparable antiglycation potential with the standard, aminoguanidine. The antioxidant potential of compound 3g was found to be excellent, with an IC₅₀ value of 28.19 ± 0.2563 μM. The binding interactions of compound 3a (binding energy = -8.833 kcal/mol) with human pancreatic α-amylase identified 3a as a potent α-amylase inhibitor. Conclusion: Enrichment of established structures with more electron-donating functionalities may assist/lead to the development of more potent antidiabetic drugs.

Coupled Effect of Polypropylene Fibers and Slag on the Impact Resistance and Mechanical Properties of Concrete

The disposal of steel slag leads to the occupation of large land areas, along with many environmental consequences, due to the release of poisonous substances into the water and soil. The use of steel slag in concrete as a sand-replacement material can assist in reducing its impacts on the environment and can be an alternative source of fine aggregates. This is the very first paper that seeks to experimentally investigate the cumulative effect of steel slag and polypropylene fibers, particularly on the impact resistance of concrete. Various concrete mixes were devised by substituting natural sand with steel slag at volumetric replacement ratios of 0%, 10%, 20%, 30%, and 40%, with and without fibers. Polypropylene fibers of 12 mm length were introduced into the steel slag concrete at 0%, 0.5%, and 1.0% by weight of cement as a reinforcing material. Performance evaluation of each mix through extensive experimental testing indicated that the use of steel slag as partial substitution of natural sand, up to a certain optimum replacement level of 30%, considerably improved the compressive strength, flexural strength, and tensile strength of the concrete by 20.4%, 23.8%, and 17.0%, respectively. Furthermore, the addition of polypropylene fibers to the steel slag concrete played a beneficial role in the improvement of strength characteristics, particularly the flexural strength and final drop weight impact energy, which had a maximum rise of 48.1% and 164%, correspondingly. Moreover, integral structure and analytical analyses have also been performed in this study to validate the experimental findings. The results obtained encourage the use of fiber-reinforced steel slag concrete (FRSLC) as a potential impact-resistant material considering the environmental advantages, with the suggested substitution, of an addition ratio of 30% and 1.0% for steel slag and polypropylene fibers, respectively.

A Novel Homomorphic Approach for Preserving Privacy of Patient Data in Telemedicine

Globally, the surge in disease and urgency in maintaining social distancing has reawakened the use of telemedicine/telehealth. Amid the global health crisis, the world adopted the culture of online consultancy. Thus, there is a need to revamp the conventional model of the telemedicine system as per the current challenges and requirements. Security and privacy of data are main aspects to be considered in this era. Data-driven organizations also require compliance with regulatory bodies, such as HIPAA, PHI, and GDPR. These regulatory compliance bodies must ensure user data privacy by implementing necessary security measures. Patients and doctors are now connected to the cloud to access medical records, e.g., voice recordings of clinical sessions. Voice data reside in the cloud and can be compromised. While searching voice data, a patient's critical data can be leaked, exposed to cloud service providers, and spoofed by hackers. Secure, searchable encryption is a requirement for telemedicine systems for secure voice and phoneme searching. This research proposes the secure searching of phonemes from audio recordings using fully homomorphic encryption over the cloud. It utilizes IBM's homomorphic encryption library (HElib) and achieves indistinguishability. Testing and implementation were done on audio datasets of different sizes while varying the security parameters. The analysis includes a thorough security analysis along with leakage profiling. The proposed scheme achieved higher levels of security and privacy, especially when the security parameters increased. However, in use cases where higher levels of security were not desirous, one may rely on a reduction in the security parameters.

Investigation of genetic relationships within three Miscanthus species using SNP markers identified with SLAF-seq

BACKGROUND

Miscanthus, which is a leading dedicated-energy grass in Europe and in parts of Asia, is expected to play a key role in the development of the future bioeconomy. However, due to its complex genetic background, it is difficult to investigate phylogenetic relationships in this genus. Here, we investigated 50 Miscanthus germplasms: 1 female parent (M. lutarioriparius), 30 candidate male parents (M. lutarioriparius, M. sinensis, and M. sacchariflorus), and 19 offspring. We used high-throughput Specific-Locus Amplified Fragment sequencing (SLAF-seq) to identify informative single nucleotide polymorphisms (SNPs) in all germplasms.

RESULTS

We identified 257,889 SLAF tags, of which 87,162 were polymorphic. Each tag was 264-364 bp long. The obtained 724,773 population SNPs were used to investigate genetic relationships within three species of Miscanthus. We constructed a phylogenetic tree of the 50 germplasms using the obtained SNPs and grouped them into two clades: one clade comprised of M. sinensis alone and the other one included the offspring, M. lutarioriparius, and M. sacchariflorus. Genetic cluster analysis had revealed that M. lutarioriparius germplasm C3 was the most likely male parent of the offspring.

CONCLUSIONS

As a high-throughput sequencing method, SLAF-seq can be used to identify informative SNPs in Miscanthus germplasms and to rapidly characterize genetic relationships within this genus. Our results will support the development of breeding programs with the focus on utilizing Miscanthus cultivars with elite biomass- or fiber-production potential for the developing bioeconomy.

Comparison of thermochemical conversion and anaerobic digestion of perennial flower-rich herbaceous wild plant species for bioenergy production

The combustion quality of three perennial wild plant species Tanacetum vulgare L., Centaurea nigra L. and Artemisia vulgaris L. was investigated in comparison to the energy yield obtained from anaerobic digestions of these biomasses. Combustion resulted in 1.5-2.8 times higher energy yield compared to anaerobic digestion. All wild plants showed a similar higher heating value to Miscanthus × giganteus Greef et Deuter and Panicum virgatum L. (16.0-17.0 MJ kg^-1). The ash-melting behavior of all wild plants was like Sida hermaphrodita L. Rusby, since the ash did not sinter at 1200 °C. However, Artemisia vulgaris L. had highest ash content (5.2-5.7% of dry matter) with a low ash melting behavior (1000 °C) attributed to a high potassium content and calculated phase composition. Therefore, careful consideration should be given to select the wild plants to meet the requirements for their use as solid biofuels in residential and commercial applications.

Nature of Unconventional Pairing in the Kagome Superconductors AV_{3}Sb_{5} (A=K,Rb,Cs)

The recent discovery of AV_{3}Sb_{5} (A=K,Rb,Cs) has uncovered an intriguing arena for exotic Fermi surface instabilities in a kagome metal. Among them, superconductivity is found in the vicinity of multiple van Hove singularities, exhibiting indications of unconventional pairing. We show that the sublattice interference mechanism is central to understanding the formation of superconductivity in a kagome metal. Starting from an appropriately chosen minimal tight-binding model with multiple van Hove singularities close to the Fermi level for AV_{3}Sb_{5}, we provide a random phase approximation analysis of superconducting instabilities. Nonlocal Coulomb repulsion, the sublattice profile of the van Hove bands, and the interaction strength turn out to be the crucial parameters to determine the preferred pairing symmetry. Implications for potentially topological surface states are discussed, along with a proposal for additional measurements to pin down the nature of superconductivity in AV_{3}Sb_{5}.

Magnetic Field Induced Quantum Spin Liquid in the Two Coupled Trillium Lattices of K_{2}Ni_{2}(SO_{4})_{3}

Quantum spin liquids are exotic states of matter that form when strongly frustrated magnetic interactions induce a highly entangled quantum paramagnet far below the energy scale of the magnetic interactions. Three-dimensional cases are especially challenging due to the significant reduction of the influence of quantum fluctuations. Here, we report the magnetic characterization of K_{2}Ni_{2}(SO_{4})_{3} forming a three-dimensional network of Ni^{2+} spins. Using density functional theory calculations, we show that this network consists of two interconnected spin-1 trillium lattices. In the absence of a magnetic field, magnetization, specific heat, neutron scattering, and muon spin relaxation experiments demonstrate a highly correlated and dynamic state, coexisting with a peculiar, very small static component exhibiting a strongly renormalized moment. A magnetic field B≳4  T diminishes the ordered component and drives the system into a pure quantum spin liquid state. This shows that a system of interconnected S=1 trillium lattices exhibits a significantly elevated level of geometrical frustration.

Green Synthesis of CeO2 Nanoparticles from the Abelmoschus esculentus Extract: Evaluation of Antioxidant, Anticancer, Antibacterial, and Wound-Healing Activities

Metal oxide nanoparticles synthesized by the biological method represent the most recent research in nanotechnology. This study reports the rapid and ecofriendly approach for the synthesis of CeO2 nanoparticles mediated using the Abelmoschus esculentus extract. The medicinal plant extract acts as both a reducing and stabilizing agent. The characterization of CeO2 NPs was performed by scanning electron microscopy (SEM), X-ray diffraction (XRD), ultraviolet-visible spectroscopy (UV-Vis), and Fourier transform infrared spectroscopy (FTIR). The in vitro cytotoxicity of green synthesized CeO2 was assessed against cervical cancerous cells (HeLa). The exposure of CeO2 to HeLa cells at 10-125 µg/mL caused a loss in cellular viability against cervical cancerous cells in a dose-dependent manner. The antibacterial activity of the CeO2 was assessed against S. aureus and K. pneumonia. A significant improvement in wound-healing progression was observed when cerium oxide nanoparticles were incorporated into the chitosan hydrogel membrane as a wound dressing.

Improved JPEG Coding by Filtering 8 × 8 DCT Blocks

The JPEG format, consisting of a set of image compression techniques, is one of the most commonly used image coding standards for both lossy and lossless image encoding. In this format, various techniques are used to improve image transmission and storage. In the final step of lossy image coding, JPEG uses either arithmetic or Huffman entropy coding modes to further compress data processed by lossy compression. Both modes encode all the 8 × 8 DCT blocks without filtering empty ones. An end-of-block marker is coded for empty blocks, and these empty blocks cause an unnecessary increase in file size when they are stored with the rest of the data. In this paper, we propose a modified version of the JPEG entropy coding. In the proposed version, instead of storing an end-of-block code for empty blocks with the rest of the data, we store their location in a separate buffer and then compress the buffer with an efficient lossless method to achieve a higher compression ratio. The size of the additional buffer, which keeps the information of location for the empty and non-empty blocks, was considered during the calculation of bits per pixel for the test images. In image compression, peak signal-to-noise ratio versus bits per pixel has been a major measure for evaluating the coding performance. Experimental results indicate that the proposed modified algorithm achieves lower bits per pixel while retaining quality.

Recent advances in the use of phytochemicals to manage gastrointestinal oxidative stress in poultry and pigs

Plants are integral components of pig and poultry feed, and aside from their raw nutritive value, some phytochemicals contain bioactive compounds. The aim of the present paper is to review recent advances in the use of some phytochemicals in pig and poultry feed, focusing on the examples of isoquinoline alkaloids, polyphenol rich sugarcane extracts and superoxide dismutase-rich melon pulp extracts. As gut health is critical for efficient production, the review will focus on recent results modulating oxidative stress within the gastrointestinal tract and the potential mechanisms of action.

Seasonal Nutrient Cycling and Enrichment of Nutrient-Related Soil Microbes Aid in the Adaptation of Ramie (Boehmeria nivea L.) to Nutrient-Deficient Conditions

The breeding for varieties tolerant of adverse growing conditions is critical for sustainable agriculture, especially for ramie (Boehmeria nivea L.). However, a lack of information on the tolerance of ramie to nutrient-deficient conditions has hindered efforts to breed ramie varieties tolerant of such conditions. The main objective of this study was to explore the tolerance strategies of ramie plants under poor soil conditions using long-term (8-9 years) field trials. Genotypes of Duobeiti 1 and Xiangzhu XB were highly tolerant of poor soil conditions. The contributions of seasonal nutrient cycling and rhizobacteria to the ability of ramie to tolerate poor soil were tested. Nitrogen and phosphorus retranslocation to the root at the end of the growing season helped ramie adapt to poor soil conditions. The contribution of the microbial community was analyzed using high-throughput Illumina MiSeq sequencing technology. The enrichment of beneficial bacteria (mainly Bradyrhizobium, Gaiella, and norank_o_Gaiellales) and the reduction of harmful fungi (mainly Cladosporium and Aspergillus) also contributed to the ability of ramie to tolerate poor soils. The results of this study provide new insight into the ability of ramie to tolerate adverse conditions and aid future efforts to breed and cultivate ramie tolerant of adverse conditions.

Recurrence Rate of Giant Cell Tumor With the Treatment of Scooping Curettage, Burr Down Technique, Phenolization, and Bone Cement

Objective: To find the recurrence and outcomes of giant cell tumors treated with scooping curettage, burr down technique, phenolization, and bone cement.

Method: We conducted a descriptive case series using a non-probability consecutive sampling technique at the Department of Orthopedics, Lahore General Hospital, Lahore, Pakistan, from May 2014 to June 2018. A total of 40 patients aged between 20 to 40 years with Compannacci grade I, II & III giant cell tumors (GCT) were included and patients unfit for the surgery, those with multiple, recurrent, malignant giant cell tumors, tumors involving the axial skeleton, and previously treated cases were excluded. We recorded the side, site of the tumor, post-operative distal neurovascular status, and recurrence of giant cell tumors. The patients were follow-up in the out-patient department (OPD) at the second week, fourth week, 12th week, 24th week, 48th week, 96th week, and 144th week after the surgery. Side, site of the tumor, and post-operative distal neurovascular status were assessed clinically, and recurrence of the tumors was observed clinically and radiologically.

Results: The mean age of all patients was 25.75±5.74 years. Males were 45% (18) and females were 55% (22). Most (12, 30%) tumors were present in the upper limb, and 22 (70%) were present in the lower limb. The majority (24, 60%) tumors were present around the knee joint. Companacci grade I was five (12.5%), grade II was 14 (35%), and grade III was 21 (52%). There were six (15%) pathological fractures. There was no case of distal neurovascular (DNV) injury, and three patients had a recurrence in two years of follow-up.

Conclusion: Giant cell tumor treated with scooping curettage, burr down technique, phenolization and poly-methyl methacrylate showed 7.5% recurrence. The combined use of local adjuvants in the treatment of giant cell tumors is a safe and effective way to reduce the rate of local recurrence.

Manual Sutureless Cataract Surgery (MSCS) in Patients with Pseudo-Exfoliation

Purpose:  To document the complications of Manual suture-less cataract surgery in eyes with pseudo-exfoliation. Study Design:  Interventional case series. Place and Duration of Study:  Naseer memorial hospital, Dadyal, Azad Jammu Kashmir, from 4 July 2017 to 3 July 2019. Methods:  One hundred and fifty patients with pseudo-exfoliation (PEX) and cataract were selected by convenient sampling. Patients with systemic diseases, history of trauma, intraocular pressure ≥15 mm Hg on Applanation tonometry and any other associated ocular disease for example retinal detachment or retinal disease, previous history of glaucoma or narrow/closed angle on Gonioscopy were excluded from the study. Dark brown cataracts were also excluded. Pseudo-exfoliation was diagnosed on slit lamp on the basis of presence of dandruff like material on the pupil and the anterior lens capsule. The patients underwent manual suture less cataract surgery under local anesthesia Intraoperative and post-operative complications were noted. first day postoperatively. The collected data and analyzed using statistical package for social sciences (SPSS) version 21 for analysis. Results:  The study group consisted of 64% males and 36% females with mean age of 65 ± 15.32 years. The most common difficulty encountered was poor pupil dilatation in 37.3% cases followed by Zonular dehiscence in 7.3%. On the first post-operative day, the most common complication was intraocular lens decentration in 2.6% of the cases. Conclusion:  Pupils of patients with pseudo-exfoliation dilate poorly and makes surgery difficult. With good pupillary dilatation, careful capsulorhexis and minimal stress on the zonules, MSCS can be safely performed in eyes with cataract and PEX. Key Words:  Pseudo-exfoliation, Cataract, Pupil.

Gut Microbiota-Polyphenol Interactions in Chicken: A Review

The gastrointestinal tract of the chicken harbors very complex and diverse microbial communities including both beneficial and harmful bacteria. However, a dynamic balance is generally maintained in such a way that beneficial bacteria predominate over harmful ones. Environmental factors can negatively affect this balance, resulting in harmful effects on the gut, declining health, and productivity. This means modulating changes in the chicken gut microbiota is an effective strategy to improve gut health and productivity. One strategy is using modified diets to favor the growth of beneficial bacteria and a key candidate are polyphenols, which have strong antioxidant potential and established health benefits. The gut microbiota-polyphenol interactions are of vital importance in their effects on the gut microbiota modulation because it affects not only the composition of gut bacteria but also improves bioavailability of polyphenols through generation of more bioactive metabolites enhancing their health effects on morphology and composition of the gut microbiota. The object of this review is to improve the understanding of polyphenol interactions with the gut microbiota and highlights their potential role in modulation of the gut microbiota of chicken.

Evidence for a three-dimensional quantum spin liquid in PbCuTe2O6

The quantum spin liquid is a highly entangled magnetic state characterized by the absence of static magnetism in its ground state. Instead, the spins fluctuate in a highly correlated way down to the lowest temperatures. Quantum spin liquids are very rare and are confined to a few specific cases where the interactions between the magnetic ions cannot be simultaneously satisfied (known as frustration). Lattices with magnetic ions in triangular or tetrahedral arrangements, which interact via isotropic antiferromagnetic interactions, can generate such a frustration. Three-dimensional isotropic spin liquids have mostly been sought in materials where the magnetic ions form pyrochlore or hyperkagome lattices. Here we present a three-dimensional lattice called the hyper-hyperkagome that enables spin liquid behaviour and manifests in the compound PbCuTe₂O₆. Using a combination of experiment and theory, we show that this system exhibits signs of being a quantum spin liquid with no detectable static magnetism together with the presence of diffuse continua in the magnetic spectrum suggestive of fractional spinon excitations.

Quantum spin liquids have magnetic moments that do not form magnetic order even as the temperature approaches zero, leading to the dominance of quantum fluctuations. Chillal et al. present evidence that the hyper-hyperkagome lattice of PbCuTe₂O₆ hosts a three-dimensional quantum spin liquid.

Environmentally responsive and anti-bugs textile finishes - Recent trends, challenges, and future perspectives

Bugs, such as microorganisms and insects, are present in the environment and sometimes can be health-hazardous if the living environment is not maintained following proper hygienic regulations. In the present scenario of increasing public awareness, environmental consciousness, and growing demand for easy-care, and disinfected textiles, the manufacturing of protective and easy-to-care textiles has become a key necessity of the modern world. Comfortable, clean, hygienic, antimicrobial, and insect repelling properties of textile goods are gaining the accelerating research momentum as a basic requirement to produce multifunctional textiles. These functional finishes have numerous applications such as in-home textiles, bed nets, and tenting, camping gear as well as in military uniforms. Synthetic antimicrobial and insect repellents are quite effective against insects and microscopic organisms but are slightly toxic to the human being and the environment. To overcome these problems, researchers are considering natural agents for functional finishes, but their effectiveness is less durable to textile material. Besides needful advantages, the excessive use of dyes in finishing processes heavily required washing cycles and ultimately release various types of hazardous dyes or wasteful effluents in the environment. This review reports the chemical composition and recent developments in textile finishes, particularly antimicrobial and insect repellent textile finishes. A large number of commonly used antimicrobial agents (i.e. chitosan, zwitterionic compounds, silver and silver-based compounds, titanium dioxide nanoparticles, imidazolium salts, triclosan and quaternary ammonium salts) and insect repellent textile finishes (i.e. N‑N‑diethyl‑m‑toluamide, permethrin, cypermethrin, pyrethrum, picaridin, bioallethrin, citriodiol and essential oils) have been presented. Finally, the review is wrapped up with major research gaps/challenges, concluding remarks, and future opportunities in this area of research.

Molecular cytogenetic characterization and phylogenetic analysis of four Miscanthus species (Poaceae)

Chromosomes of four Miscanthus (Andersson, 1855) species including M. sinensis (Andersson, 1855), M. floridulus (Schumann & Lauterb, 1901), M. sacchariflorus (Hackel, 1882) and M. lutarioriparius (Chen & Renvoize, 2005) were analyzed using sequentially combined PI and DAPI (CPD) staining and fluorescence in situ hybridization (FISH) with 45S rDNA probe. To elucidate the phylogenetic relationship among the four Miscanthus species, the homology of repetitive sequences among the four species was analyzed by comparative genomic in situ hybridization (cGISH). Subsequently four Miscanthus species were clustered based on the internal transcribed spacer (ITS) of 45S rDNA. Molecular cytogenetic karyotypes of the four Miscanthus species were established for the first time using chromosome measurements, fluorochrome bands and 45S rDNA FISH signals, which will provide a cytogenetic tool for the identification of these four species. All the four have the karyotype formula of Miscanthus species, which is 2n = 2x = 38 = 34m(2SAT) + 4sm, and one pair of 45S rDNA sites. The latter were shown as strong red bands by CPD staining. A non-rDNA CPD band emerged in M. floridulus and some blue DAPI bands appeared in M. sinensis and M. floridulus. The hybridization signals of M. floridulus genomic DNA to the chromosomes of M. sinensis and M. lutarioriparius genomic DNA to the chromosomes of M. sacchariflorus were stronger and more evenly distributed than other combinations. Molecular phylogenetic trees showed that M. sinensis and M. floridulus were closest relatives, and M. sacchariflorus and M. lutarioriparius were also closely related. These findings were consistent with the phylogenetic relationships inferred from the cGISH patterns.

Acute Myeloid Leukemia with t(8;21)(q22;q22) and Trisomy 4: A Rare Occurrence in a Female Child

Acute myeloid leukemia (AML) with balanced translocation t (8;21) is one of the most frequent chromosomal abnormalities and carries a favorable clinical outcome. However, according to a literature review, additional chromosomal aberrations can affect the overall disease prognosis. Trisomy 4 is a rare numerical abnormality in AML patients with t (8;21), which can be associated with c-KIT gene involvement. In adults, c-KIT mutation carries an unfavorable clinical outcome; however, its incidence and clinical importance in the pediatric population are still under scrutiny. Here, we report a case of AML with t(8;21) and trisomy 4 in an eight-year-old female child and the clinical course of the disease.

Characterization of Miscanthus cell wall polymers

Efficient utilization of lignocellulosic Miscanthus biomass for the production of biochemicals, such as ethanol, is challenging due to its recalcitrance, which is influenced by the individual plant cell wall polymers and their interactions. Lignocellulosic biomass composition differs depending on several factors, such as plant age, harvest date, organ type, and genotype. Here, four selected Miscanthus genotypes (Miscanthus sinensis, Miscanthus sacchariflorus, Miscanthus × giganteus, Miscanthus sinensis × Miscanthus sacchariflorus hybrid) were grown and harvested, separated into stems and leaves, and characterized for their non-starch polysaccharide composition and structures, lignin contents and structures, and hydroxycinnamate profiles (monomers and ferulic acid dehydrodimers). Polysaccharides of all genotypes are mainly composed of cellulose and low-substituted arabinoxylans. Ratios of hemicelluloses to cellulose were comparable, with the exception of Miscanthus sinensis that showed a higher hemicellulose/cellulose ratio. Lignin contents of Miscanthus stems were higher than those of Miscanthus leaves. Considering the same organs, the four genotypes did not differ in their Klason lignin contents, but Miscanthus × giganteus showed the highest acetylbromide soluble lignin content. Lignin polymers isolated from stems varied in their S/G ratios and linkage type distributions across genotypes. p-Coumaric acid was the most abundant ester-bound hydroxycinnamte monomer in all samples. Ferulic acid dehydrodimers were analyzed as cell wall cross-links, with 8-5-coupled diferulic acid being the main dimer, followed by 8-O-4-, and 5-5-diferulic acid. Contents of p-coumaric acid, ferulic acid, and ferulic acid dimers varied depending on genotype and organ type. The largest amount of cell wall cross-links was analyzed for Miscanthus sinensis.

Implementation of the cobas Liat influenza point-of-care test into an emergency department during a high-incidence season: a retrospective evaluation following real-world implementation

The cobas Liat influenza A/B and respiratory syncytial virus (RSV) assay (Liat) was used in the adult emergency department of a large London hospital from 21^st January 2018 to 14^th April 2018. Influenza was detected in 308 of 1027 (30%) samples tested; influenza A in 157 (15.3%), influenza B in 149 (14.5%) and RSV in 28 (2.7%). When compared against Fast Track Diagnostics Respiratory Pathogens 21 multiplex polymerase chain reaction and Cepheid Xpert Xpress Flu/RSV assay, Liat performance for the detection of influenza A or B was: sensitivity 85% [95% confidence interval (CI) 76–92)], specificity 98% (95% CI 97–99), negative predictive value 94% (95% CI 92–96) and positive predictive value 95% (95% CI 91–97).

Clinical presentation of atrial myxomas does it differ in left or right sided tumor?

OBJECTIVE

This paper reports a 20 years' experience in the management of atrial myxomas at our institution. Apart from presenting our experience of their clinical presentation, surgical management, post-operative complication, and long-term follow-up we investigated any correlation between left and right sided tumor with their symptom of presentation.

MATERIALS AND METHODS

The data were retrospectively collected for patients between the period 1995 and 2015 from the hospital database. The follow-up was conducted by questionnaire received from the patients describing their current status.

RESULTS

Fifty four consecutive patients underwent surgical resection for atrial myxomas. The mean age was 62 years (standard deviation [SD]: ±14 years) with a larger number of female (55.5%) patients. The most common location for the tumor was the left atrium (70.3%) with the atrial septum being the most common (63%) site of attachment. The tumors presented in a variety of ways, namely, as shortness of breath (37.03%), transient ischemic attack (24.07%), and chest pains (22.2%) being the more common modes of presentation. Left heart tumors presented 6 years earlier with more severe shortness of breath as compared to right-sided tumors. Post-operative atrial fibrillation occurred in 22.2% of patients. Concomitant surgical procedures were required in 26% of patient. The median length of post-operative hospital stay was 6 days (IQR: 5; 9). There were 2 (3.7%) in-hospital mortalities and 4 (7.4%) later deaths at 2, 3, 7, and 15 years, respectively. Long-term follow-up actuarial Kaplan-Meire survival for the whole group was 92.6 ± 3.6% at 20 years with a significant reduction in the severity of shortness of breath.

CONCLUSION

Cardiac myxoma is the most common form of the cardiac tumor with a slight female preponderance. Left-sided tumors present earlier than right-sided tumors with more severe shortness of breath. Excellent long-term results can be achieved with surgical intervention for cardiac myxomas, including any concomitant interventions. In particular, a sustained reduction in shortness of breath is observed.

Vaginal Yolk Sac Tumor in an Infant

Yolk sac tumors are most common tumors among the germ cell tumors (GCTs) in children, mostly involving the gonads. But yolk sac tumors involving the vagina are very rare. These usually present with per vaginal bleeding and vaginal mass. Presentation with discharged tumor fragments is very unusual. We present a rare case of yolk sac tumor of vagina in an infant with very unusual presentation of per vaginal tumor tissue discharge, histopathological examination of which was diagnostic.

Environmental Influences on the Growing Season Duration and Ripening of Diverse Miscanthus Germplasm Grown in Six Countries

The development of models to predict yield potential and quality of a Miscanthus crop must consider climatic limitations and the duration of growing season. As a biomass crop, yield and quality are impacted by the timing of plant developmental transitions such as flowering and senescence. Growth models are available for the commercially grown clone Miscanthus x giganteus (Mxg), but breeding programs have been working to expand the germplasm available, including development of interspecies hybrids. The aim of this study was to assess the performance of diverse germplasm beyond the range of environments considered suitable for a Miscanthus crop to be grown. To achieve this, six field sites were planted as part of the EU OPTIMISC project in 2012 in a longitudinal gradient from West to East: Wales-Aberystwyth, Netherlands-Wageningen, Stuttgart-Germany, Ukraine-Potash, Turkey-Adana, and Russia-Moscow. Each field trial contained three replicated plots of the same 15 Miscanthus germplasm types. Through the 2014 growing season, phenotypic traits were measured to determine the timing of developmental stages key to ripening; the tradeoff between growth (yield) and quality (biomass ash and moisture content). The hottest site (Adana) showed an accelerated growing season, with emergence, flowering and senescence occurring before the other sites. However, the highest yields were produced at Potash, where emergence was delayed by frost and the growing season was shortest. Flowering triggers varied with species and only in Mxg was strongly linked to accumulated thermal time. Our results show that a prolonged growing season is not essential to achieve high yields if climatic conditions are favorable and in regions where the growing season is bordered by frost, delaying harvest can improve quality of the harvested biomass.

Harvest Time Optimization for Combustion Quality of Different Miscanthus Genotypes across Europe

Delayed harvest can improve the quality of miscanthus biomass for combustion and enhance the long-term sustainability of the crop, despite accompanying yield losses. The aim of this study is to identify the optimal harvesting time, which can deliver improved biomass quality for combustion of novel miscanthus genotypes at various sites across Europe, without high yield losses and without compromising their environmental performance. The relevant field trials were established as part of the European project OPTIMISC with 15 genotypes at six sites across Europe. For this study, the five highest yielding genotypes from each germplasm group and three sites with contrasting climatic conditions (Stuttgart, Germany; Adana, Turkey; and Moscow, Russia) were selected for assessment. The biomass samples were collected between August and March (depending on site) and subjected to mineral and ash content analysis. At Stuttgart, the delay in harvesting time led to a significant variation in combustion quality characteristics, such as N content (0.64-0.21%), ash content (5.15-2.60%), and ash sintering index (1.30-0.20). At Adana, the delay in harvesting time decreased the N content from 0.62 to 0.23%, ash content from 10.63 to 3.84%, and sintering index from 0.54 to 0.07. At Moscow, the impact of delay in harvesting was not significant, except for N, Mg, and ash sintering index. Overall, a delay in harvesting time improved the combustion quality characteristics of each genotype, but at the expense of yield. Yield losses of up to 49% in Stuttgart and Adana and 21% for Moscow were recorded, with variations between genotypes and sites. The harvesting time also affected nutrient offtake, which in turn influences the long-term environmental performance of the crop. The highest N, P, and K offtakes were recorded at Stuttgart for each harvesting time except for final harvest (March), where Moscow had the highest N offtake. This study describes the three criteria (biomass quality, yield losses, nutrient offtake) for determining the ideal harvesting time, which gives the best compromise between dry matter yields and biomass quality characteristics without negatively affecting the environmental performance of the crop.

Extending Miscanthus Cultivation with Novel Germplasm at Six Contrasting Sites

Miscanthus is a genus of perennial rhizomatous grasses with C4 photosynthesis which is indigenous in a wide geographic range of Asian climates. The sterile clone, Miscanthus × giganteus (M. × giganteus), is a naturally occurring interspecific hybrid that has been used commercially in Europe for biomass production for over a decade. Although, M. × giganteus has many outstanding performance characteristics including high yields and low nutrient offtakes, commercial expansion is limited by cloning rates, slow establishment to a mature yield, frost, and drought resistance. In this paper, we evaluate the performance of 13 novel germplasm types alongside M. × giganteus and horticultural "Goliath" in trials in six sites (in Germany, Russia, The Netherlands, Turkey, UK, and Ukraine). Mean annual yields across all the sites and genotypes increased from 2.3 ± 0.2 t dry matter ha-1 following the first year of growth, to 7.3 ± 0.3, 9.5 ± 0.3, and 10.5 ± 0.2 t dry matter ha-1 following the second, third, and fourth years, respectively. The highest average annual yields across locations and four growth seasons were observed for M. × giganteus (9.9 ± 0.7 t dry matter ha-1) and interspecies hybrid OPM-6 (9.4 ± 0.6 t dry matter ha-1). The best of the new hybrid genotypes yielded similarly to M. × giganteus at most of the locations. Significant effects of the year of growth, location, species, genotype, and interplay between these factors have been observed demonstrating strong genotype × environment interactions. The highest yields were recorded in Ukraine. Time needed for the crop establishment varied depending on climate: in colder climates such as Russia the crop has not achieved its peak yield by the fourth year, whereas in the hot climate of Turkey and under irrigation the yields were already high in the first growing season. We have identified several alternatives to M. × giganteus which have provided stable yields across wide climatic ranges, mostly interspecies hybrids, and also Miscanthus genotypes providing high biomass yields at specific geographic locations. Seed-propagated interspecific and intraspecific hybrids, with high stable yields and cheaper reliable scalable establishment remain a key strategic objective for breeders.

Site-Specific Management of Miscanthus Genotypes for Combustion and Anaerobic Digestion: A Comparison of Energy Yields

In Europe, the perennial C4 grass miscanthus is currently mainly cultivated for energy generation via combustion. In recent years, anaerobic digestion has been identified as a promising alternative utilization pathway. Anaerobic digestion produces a higher-value intermediate (biogas), which can be upgraded to biomethane, stored in the existing natural gas infrastructure and further utilized as a transport fuel or in combined heat and power plants. However, the upgrading of the solid biomass into gaseous fuel leads to conversion-related energy losses, the level of which depends on the cultivation parameters genotype, location, and harvest date. Thus, site-specific crop management needs to be adapted to the intended utilization pathway. The objectives of this paper are to quantify (i) the impact of genotype, location and harvest date on energy yields of anaerobic digestion and combustion and (ii) the conversion losses of upgrading solid biomass into biogas. For this purpose, five miscanthus genotypes (OPM 3, 6, 9, 11, 14), three cultivation locations (Adana, Moscow, Stuttgart), and up to six harvest dates (August-March) were assessed. Anaerobic digestion yielded, on average, 35% less energy than combustion. Genotype, location, and harvest date all had significant impacts on the energy yield. For both, this is determined by dry matter yield and ash content and additionally by substrate-specific methane yield for anaerobic digestion and moisture content for combustion. Averaged over all locations and genotypes, an early harvest in August led to 25% and a late harvest to 45% conversion losses. However, each utilization option has its own optimal harvest date, determined by biomass yield, biomass quality, and cutting tolerance. By applying an autumn green harvest for anaerobic digestion and a delayed harvest for combustion, the conversion-related energy loss was reduced to an average of 18%. This clearly shows that the delayed harvest required to maintain biomass quality for combustion is accompanied by high energy losses through yield reduction over winter. The pre-winter harvest applied in the biogas utilization pathway avoids these yield losses and largely compensates for the conversion-related energy losses of anaerobic digestion.

Novel Miscanthus Germplasm-Based Value Chains: A Life Cycle Assessment

In recent years, considerable progress has been made in miscanthus research: improvement of management practices, breeding of new genotypes, especially for marginal conditions, and development of novel utilization options. The purpose of the current study was a holistic analysis of the environmental performance of such novel miscanthus-based value chains. In addition, the relevance of the analyzed environmental impact categories was assessed. A Life Cycle Assessment was conducted to analyse the environmental performance of the miscanthus-based value chains in 18 impact categories. In order to include the substitution of a reference product, a system expansion approach was used. In addition, a normalization step was applied. This allowed the relevance of these impact categories to be evaluated for each utilization pathway. The miscanthus was cultivated on six sites in Europe (Aberystwyth, Adana, Moscow, Potash, Stuttgart and Wageningen) and the biomass was utilized in the following six pathways: (1) small-scale combustion (heat)-chips; (2) small-scale combustion (heat)-pellets; (3) large-scale combustion (CHP)-biomass baled for transport and storage; (4) large-scale combustion (CHP)-pellets; (5) medium-scale biogas plant-ensiled miscanthus biomass; and (6) large-scale production of insulation material. Thus, in total, the environmental performance of 36 site × pathway combinations was assessed. The comparatively high normalized results of human toxicity, marine, and freshwater ecotoxicity, and freshwater eutrophication indicate the relevance of these impact categories in the assessment of miscanthus-based value chains. Differences between the six sites can almost entirely be attributed to variations in biomass yield. However, the environmental performance of the utilization pathways analyzed varied widely. The largest differences were shown for freshwater and marine ecotoxicity, and freshwater eutrophication. The production of insulation material had the lowest impact on the environment, with net benefits in all impact categories expect three (marine eutrophication, human toxicity, agricultural land occupation). This performance can be explained by the multiple use of the biomass, first as material and subsequently as an energy carrier, and by the substitution of an emission-intensive reference product. The results of this study emphasize the importance of assessing all environmental impacts when selecting appropriate utilization pathways.

Efficiency of single stage- and two stage pretreatment in biomass with different lignin content

In current study the enzymatic glucose yields of miscanthus and wheat straw were compared after single stage- and two stage pretreatment with dilute sulfuric acid at different pretreatment severities. Glucose yields after two stage pretreatment were higher than after single stage pretreatment in miscanthus. Whereas wheat straw had higher glucose yields after single stage pretreatment. The study shows that two stage pretreatment has a negative effect on glucose yield in biomass with low not-acid-degradable lignin content and a positive one in biomass with high not-acid-degradable lignin content. The not-acid-degradable lignin fraction offers a higher degree of protection of the whole lignin structure against chemical attacks by mineral acids. More severe pretreatment conditions were needed to achieve a sufficient breakup of the lignin structure. But more severe conditions enhance resin formation, leading to lower enzyme activity and reduced carbohydrate yields.

Progress on Optimizing Miscanthus Biomass Production for the European Bioeconomy: Results of the EU FP7 Project OPTIMISC

This paper describes the complete findings of the EU-funded research project OPTIMISC, which investigated methods to optimize the production and use of miscanthus biomass. Miscanthus bioenergy and bioproduct chains were investigated by trialing 15 diverse germplasm types in a range of climatic and soil environments across central Europe, Ukraine, Russia, and China. The abiotic stress tolerances of a wider panel of 100 germplasm types to drought, salinity, and low temperatures were measured in the laboratory and a field trial in Belgium. A small selection of germplasm types was evaluated for performance in grasslands on marginal sites in Germany and the UK. The growth traits underlying biomass yield and quality were measured to improve regional estimates of feedstock availability. Several potential high-value bioproducts were identified. The combined results provide recommendations to policymakers, growers and industry. The major technical advances in miscanthus production achieved by OPTIMISC include: (1) demonstration that novel hybrids can out-yield the standard commercially grown genotype Miscanthus x giganteus; (2) characterization of the interactions of physiological growth responses with environmental variation within and between sites; (3) quantification of biomass-quality-relevant traits; (4) abiotic stress tolerances of miscanthus genotypes; (5) selections suitable for production on marginal land; (6) field establishment methods for seeds using plugs; (7) evaluation of harvesting methods; and (8) quantification of energy used in densification (pellet) technologies with a range of hybrids with differences in stem wall properties. End-user needs were addressed by demonstrating the potential of optimizing miscanthus biomass composition for the production of ethanol and biogas as well as for combustion. The costs and life-cycle assessment of seven miscanthus-based value chains, including small- and large-scale heat and power, ethanol, biogas, and insulation material production, revealed GHG-emission- and fossil-energy-saving potentials of up to 30.6 t CO_2eq C ha^-1y^-1 and 429 GJ ha^-1y^-1, respectively. Transport distance was identified as an important cost factor. Negative carbon mitigation costs of -78€ t^-1 CO_2eq C were recorded for local biomass use. The OPTIMISC results demonstrate the potential of miscanthus as a crop for marginal sites and provide information and technologies for the commercial implementation of miscanthus-based value chains.

A methodology for comprehensive breast cancer Ki67 labeling index with intra-tumor heterogeneity appraisal based on hexagonal tiling of digital image analysis data

Digital image analysis (DIA) enables higher accuracy, reproducibility, and capacity to enumerate cell populations by immunohistochemistry; however, the most unique benefits may be obtained by evaluating the spatial distribution and intra-tissue variance of markers. The proliferative activity of breast cancer tissue, estimated by the Ki67 labeling index (Ki67 LI), is a prognostic and predictive biomarker requiring robust measurement methodologies. We performed DIA on whole-slide images (WSI) of 302 surgically removed Ki67-stained breast cancer specimens; the tumour classifier algorithm was used to automatically detect tumour tissue but was not trained to distinguish between invasive and non-invasive carcinoma cells. The WSI DIA-generated data were subsampled by hexagonal tiling (HexT). Distribution and texture parameters were compared to conventional WSI DIA and pathology report data. Factor analysis of the data set, including total numbers of tumor cells, the Ki67 LI and Ki67 distribution, and texture indicators, extracted 4 factors, identified as entropy, proliferation, bimodality, and cellularity. The factor scores were further utilized in cluster analysis, outlining subcategories of heterogeneous tumors with predominant entropy, bimodality, or both at different levels of proliferative activity. The methodology also allowed the visualization of Ki67 LI heterogeneity in tumors and the automated detection and quantitative evaluation of Ki67 hotspots, based on the upper quintile of the HexT data, conceptualized as the "Pareto hotspot". We conclude that systematic subsampling of DIA-generated data into HexT enables comprehensive Ki67 LI analysis that reflects aspects of intra-tumor heterogeneity and may serve as a methodology to improve digital immunohistochemistry in general.

Comparing the performance of Miscanthus x giganteus and wheat straw biomass in sulfuric acid based pretreatment

The objective of this study was to assess and compare the suitability of Miscanthus x giganteus and wheat straw biomass in dilute acid catalyzed pretreatment. Miscanthus and wheat straw were treated in a dilute sulfuric acid/steam explosion pretreatment. As a result of combining dilute sulfuric acid- and steam explosion pretreatment the hemicellulose hydrolysis yields (96% in wheat straw and 90% in miscanthus) in both substrates were higher than reported in literature. The combined severity factor (=CSF) for optimal hemicellulose hydrolysis was 1.9 and 1.5 in for miscanthus and wheat straw respectively. Because of the higher CSF value more furfural, furfuryl alcohol, 5-hydroxymethylfurfural and acetic acid was formed in miscanthus than in wheat straw pretreatment.

A methodology to ensure and improve accuracy of Ki67 labelling index estimation by automated digital image analysis in breast cancer tissue

Introduction

Immunohistochemical Ki67 labelling index (Ki67 LI) reflects proliferative activity and is a potential prognostic/predictive marker of breast cancer. However, its clinical utility is hindered by the lack of standardized measurement methodologies. Besides tissue heterogeneity aspects, the key element of methodology remains accurate estimation of Ki67-stained/counterstained tumour cell profiles. We aimed to develop a methodology to ensure and improve accuracy of the digital image analysis (DIA) approach.

Methods

Tissue microarrays (one 1-mm spot per patient, n = 164) from invasive ductal breast carcinoma were stained for Ki67 and scanned. Criterion standard (Ki67-Count) was obtained by counting positive and negative tumour cell profiles using a stereology grid overlaid on a spot image. DIA was performed with Aperio Genie/Nuclear algorithms. A bias was estimated by ANOVA, correlation and regression analyses. Calibration steps of the DIA by adjusting the algorithm settings were performed: first, by subjective DIA quality assessment (DIA-1), and second, to compensate the bias established (DIA-2). Visual estimate (Ki67-VE) on the same images was performed by five pathologists independently.

Results

ANOVA revealed significant underestimation bias (P < 0.05) for DIA-0, DIA-1 and two pathologists’ VE, while DIA-2, VE-median and three other VEs were within the same range. Regression analyses revealed best accuracy for the DIA-2 (R-square = 0.90) exceeding that of VE-median, individual VEs and other DIA settings. Bidirectional bias for the DIA-2 with overestimation at low, and underestimation at high ends of the scale was detected. Measurement error correction by inverse regression was applied to improve DIA-2-based prediction of the Ki67-Count, in particular for the clinically relevant interval of Ki67-Count < 40%. Potential clinical impact of the prediction was tested by dichotomising the cases at the cut-off values of 10, 15, and 20%. Misclassification rate of 5-7% was achieved, compared to that of 11-18% for the VE-median-based prediction.

Conclusions

Our experiments provide methodology to achieve accurate Ki67-LI estimation by DIA, based on proper validation, calibration, and measurement error correction procedures, guided by quantified bias from reference values obtained by stereology grid count. This basic validation step is an important prerequisite for high-throughput automated DIA applications to investigate tissue heterogeneity and clinical utility aspects of Ki67 and other immunohistochemistry (IHC) biomarkers.

Digital immunohistochemistry platform for the staining variation monitoring based on integration of image and statistical analyses with laboratory information system

Background

Digital immunohistochemistry (IHC) is one of the most promising applications brought by new generation image analysis (IA). While conventional IHC staining quality is monitored by semi-quantitative visual evaluation of tissue controls, IA may require more sensitive measurement. We designed an automated system to digitally monitor IHC multi-tissue controls, based on SQL-level integration of laboratory information system with image and statistical analysis tools.

Methods

Consecutive sections of TMA containing 10 cores of breast cancer tissue were used as tissue controls in routine Ki67 IHC testing. Ventana slide label barcode ID was sent to the LIS to register the serial section sequence. The slides were stained and scanned (Aperio ScanScope XT), IA was performed by the Aperio/Leica Colocalization and Genie Classifier/Nuclear algorithms. SQL-based integration ensured automated statistical analysis of the IA data by the SAS Enterprise Guide project. Factor analysis and plot visualizations were performed to explore slide-to-slide variation of the Ki67 IHC staining results in the control tissue.

Results

Slide-to-slide intra-core IHC staining analysis revealed rather significant variation of the variables reflecting the sample size, while Brown and Blue Intensity were relatively stable. To further investigate this variation, the IA results from the 10 cores were aggregated to minimize tissue-related variance. Factor analysis revealed association between the variables reflecting the sample size detected by IA and Blue Intensity. Since the main feature to be extracted from the tissue controls was staining intensity, we further explored the variation of the intensity variables in the individual cores. MeanBrownBlue Intensity ((Brown+Blue)/2) and DiffBrownBlue Intensity (Brown-Blue) were introduced to better contrast the absolute intensity and the colour balance variation in each core; relevant factor scores were extracted. Finally, tissue-related factors of IHC staining variance were explored in the individual tissue cores.

Conclusions

Our solution enabled to monitor staining of IHC multi-tissue controls by the means of IA, followed by automated statistical analysis, integrated into the laboratory workflow. We found that, even in consecutive serial tissue sections, tissue-related factors affected the IHC IA results; meanwhile, less intense blue counterstain was associated with less amount of tissue, detected by the IA tools.

Medical students' perspective about factors motivating participation in small group discussions

OBJECTIVE

To assess perceptions of medical students about the factors that may enhance motivation for learning through small group discussions.

METHODS

The qualitative descriptive study was conducted in May, 2013, at Riphah International University, Islamabad, and comprised undergraduate medical students from the first to the fourth year who were given a questionnaire that sought their opinion about group characteristics, composition, expectations from the teachers, environment, additional tools and optimum time duration. The effects of granting extra marks for active participation, feedback and weightage of attendance in enhancing motivation in small group discussions were also explored. Common themes from within the responses were highlighted.

RESULTS

Initially, 400 students were given the questionnaire, but complete responses were received from 290(72.5%). About the effective group size, 221(76.2%) suggested 12 or less students, while 153(52.75%) thought groups should be divided into subgroups according to the task, and 148(51.03%) were in favour of mixed gender composition of a group. A comfortable and air-conditioned environment was suggested as a motivating factor by 156(53.79%) students. Use of models, laptops and internet during the discussion was suggested by 97(33.44%) students, and 232(80%) suggested an hour or less as sufficient time. Grant of extra marks 209(72.06%), feedback 220(75.86%) and weightage of attendance 193(66.55%) were all considered positive motivating factors. Finally, 250(86.20%) were in favour of continuation of small group discussion as a learning tool.

CONCLUSION

Most students thought a smaller size makes a small group discussion more effective, and that it should continue to be used as one of the learning modalities.

Intraoperative and early postoperative complications of manual sutureless cataract extraction

OBJECTIVE

To determine the intraoperative and early postoperative complications of manual sutureless cataract extraction.

STUDY DESIGN

Case series.

PLACE AND DURATION OF STUDY

Redo Eye Hospital, Rawalpindi, Pakistan, from January 2009 to December 2010.

METHODOLOGY

Three hundred patients of cataract through purposive non-probability sampling were selected. The patients underwent manual sutureless cataract surgery (MSCS) by single experienced surgeon and intraoperative complications were documented. The surgical technique was modified to deal with any intraoperative complications accordingly. Patients were examined on the first postoperative day and on the first postoperative week for any postoperative complications. The data was entered in Statistical Package for Social Sciences (SPSS) version 13.0 and the results were calculated in frequencies.

RESULTS

Among the 300 cases, 81.3% surgeries went uneventful whereas 18.6% had some complication. The common intraoperative complications were superior button-hole formation in 5%; posterior capsular rent in 5% and premature entry with iris prolapse in 3% cases. Postoperatively, the commonly encountered complications were striate keratopathy in 9.6% and hyphema 9%. At first week follow-up, 4% had striate keratopathy and 0.6% had hyphema. Striate keratopathy resolved with topical medication on subsequent follow-up. A total of 9 cases (3%) underwent second surgery: 2 cases for lens matter wash, 2 cases for hyphema and 5 cases needed suturing of wound for shallow anterior chamber due to wound leak.

CONCLUSION

Superior button-hole formation, posterior capsular rent and premature entry were the common intraoperative complications of MSCS whereas the common early postoperative complications were striate keratopathy and hyphema.

Abstract B116: A methodology to ensure and improve accuracy of Ki67 digital immunohistochemistry analysis in breast cancer tissue

Background: Immunohistochemical Ki67 evaluation reflects proliferative activity and is one of most important prognostic/predictive markers of breast cancer. However, standardized and efficient methodologies to accurately and reproducibly measure the Ki67 expression are still to come. Besides tissue processing, sampling, intra-tumour variability, and many other aspects to be considered, key element of the methodology remains accurate enumeration of Ki67-labelling index (LI). We aimed to develop a methodology to estimate and improve accuracy of automated image analysis (IA) approach.

Methods: Tissue microarrays (1 mm diameter spot per patient, n=164) from invasive ductal breast carcinoma, stained for Ki67 and digitized by Aperio XT scanner, were used for the study. Reference values (RV) were obtained by counting the LI using stereological frame overlaid on a spot image. To test the degree of inter-observer variation in establishing the RV, the frame counts were performed by 3 observers independently in a subset (n=30) of the TMA images. IA was performed with Aperio Genie/Nuclear algorithms enabling automated selection of tumour tissue. Accuracy of the IA compared to the RV was estimated based on ANOVA, correlation and regression analyses performed with SAS 9.3. Agreement between individual measurements was also estimated based on 95% confidence intervals calculated from the RV according to stereology rules. Several iterations of the IA with adjusted algorithm settings were performed to improve the accuracy. Highly automated calibration cycles were enabled by developing software to integrate processes of the image and statistical analyses. Visual evaluation for the LI on the same images was performed by 3 pathologists (P1, P2, P3).

Results: Inter-observer variation between 3 independent frame counts (n=30) was negligible by ANOVA (respectively, mean RV were 28.5, 28.6 and 29.9%) with correlation coefficients 0.97 and above. RV correlated strongly with IA (r=0.95) and P1, P2, P3 (r=0.86, r=0.90, r=0.92, respectively), p&lt;0.0001. ANOVA revealed no significant pairwise differences of the LI means of RV(40%) versus IA(37%), P2(43%), or P3(44%); however, the IA versus P2, P3 differed, and P1(24%) was significantly lower compared to all other measurements (p&lt;0.05). Regression analysis to predict the RV revealed best performance for the IA results with R-square of 0.90 compared to 0.74, 0.82, and 0.85 of P1, P2, and P3, respectively. The IA results reported above were achieved by a third iteration of the IA calibration, while the results of the initial two IA settings revealed a significant bias to lower values by ANOVA and lower R-square values (0.86 and 0.87) by regression analyses, when compared to the RV. Similarly, correlation coefficients and agreement between individual IA measurements and RV improved during the calibration process.

Conclusion: Our experiments provide sound and efficient methodology to achieve accurate immunohistochemical Ki67 enumeration by IA, enabled by proper validation and calibration of the measurement against RV obtained by stereological frame counts.

Citation Format: Arvydas Laurinavicius, Benoit Plancoulaine, Aida Laurinaviciene, Paulette Herlin, Raimundas Meskauskas, Indra Baltrusaityte, Justinas Besusparis, Nicolas Elie, Philippe Belhomme, Yasir Iqbal, Catherine Bor-Angelier. A methodology to ensure and improve accuracy of Ki67 digital immunohistochemistry analysis in breast cancer tissue. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Breast Cancer Research: Genetics, Biology, and Clinical Applications; Oct 3-6, 2013; San Diego, CA. Philadelphia (PA): AACR; Mol Cancer Res 2013;11(10 Suppl):Abstract nr B116.

Yolk sac tumour arising in mature teratoma in the parapharyngeal space

Yolk sac tumour is germ cell tumour commonly found in children and infants under three years of age in its pure form with a good prognosis. The commonest location for the yolk sac tumour is gonads i.e. testis and gonads. Yolk sac tumour is rarely reported in extra- gonadal locations. Parapharyngeal space is an uncommon site for mature teratoma and very few cases have been reported in adults and children. Malignant transformation in a mature teratoma in the extragonadal sites has been reported but development of yolk sac tumour has not been reported so far in the world literature. We report to our knowledge, the only and first case of yolk sac tumour arising in a mature teratoma presenting as a parapharyngeal mass in a four year old male child.

Flexible web-based integration of distributed large-scale human protein interaction maps

Protein-protein interactions constitute the backbone of many molecular processes. This has motivated the recent construction of several large-scale human protein-protein interaction maps [1-10]. Although these maps clearly offer a wealth of information, their use is challenging: complexity, rapid growth, and fragmentation of interaction data hamper their usability. To overcome these hurdles, we have developed a publicly accessible database termed UniHI (Unified Human Interactome) for integration of human protein-protein interaction data. This database is designed to provide biomedical researchers a common platform for exploring previously disconnected human interaction maps. UniHI offers researchers flexible integrated tools for accessing comprehensive information about the human interactome. Several features included in the UniHI allow users to perform various types of network-oriented and functional analysis. At present, UniHI contains over 160,000 distinct interactions between 17,000 unique proteins from ten major interaction maps derived by both computational and experimental approaches [1-10]. Here we describe the details of the implementation and maintenance of UniHI and discuss the challenges that have to be addressed for a successful integration of interaction data.

UniHI: an entry gate to the human protein interactome

Systematic mapping of protein-protein interactions has become a central task of functional genomics. To map the human interactome, several strategies have recently been pursued. The generated interaction datasets are valuable resources for scientists in biology and medicine. However, comparison reveals limited overlap between different interaction networks. This divergence obstructs usability, as researchers have to interrogate numerous heterogeneous datasets to identify potential interaction partners for proteins of interest. To facilitate direct access through a single entry gate, we have started to integrate currently available human protein interaction data in an easily accessible online database. It is called UniHI (Unified Human Interactome) and is available at http://www.mdc-berlin.de/unihi. At present, it is based on 10 major interaction maps derived by computational and experimental methods. It includes more than 150,000 distinct interactions between more than 17 000 unique human proteins. UniHI provides researchers with a flexible integrated tool for finding and using comprehensive information about the human interactome.