Interfacial Growth of Large Area Single-Crystalline Silver Sheets Through Ambient Microdroplets

The creation of micrometer-sized sheets of silver at the air-water interface by direct deposition of electrospray-generated silver ions (Ag+) on an aqueous dispersion of reduced graphene oxide (RGO), in ambient conditions, is reported. In the process of electrospray deposition (ESD), an electrohydrodynamic flow is created in the aqueous dispersion, and the graphene sheets assemble, forming a thin film at the air-water interface. The deposited Ag+ coalesce to make single-crystalline Ag sheets on top of this assembled graphene layer. Fast neutralization of Ag+ forming atomic Ag, combined with their enhanced mobility on graphene surfaces, presumably facilitates the growth of larger Ag clusters. Moreover, restrictions imposed by the interface drive the crystal growth in 2D. By controlling the precursor salt concentration, RGO concentration, deposition time, and ion current, the dimensionality of the Ag sheets can be tuned. These Ag sheets are effective substrates for surface-enhanced Raman spectroscopy (SERS), as demonstrated by the successful detection of methylene blue at nanomolar concentrations.

Coronary calcification is independently associated with major adverse cardiovascular events in men with recurrent prostate cancer while aortic calcification is not

Background

Cardiovascular disease is an important cause of morbidity and mortality in men with prostate cancer. Coronary and aortic calcification have been associated with major adverse cardiovascular events (MACE) in the general population, and are readily seen on staging cancer positron emission tomography (PET)/computed tomography (CT) scans. The utility of vascular calcification on non-gated CT for cardiovascular risk assessment in men with prostate cancer is not known.

Purpose

We determined the association between coronary and aortic calcification on non-gated CT imaging and MACE in men with prostate cancer.

Methods

We studied 354 men who underwent indium-111 capromab pendetide PET/CT for recurrent prostate cancer at our institution between 2012–2016. Clinical data were obtained from the medical record. Coronary and aortic calcification were qualitatively assessed using a standardized scoring system. The primary outcome of MACE included myocardial infarction, stroke, coronary and/or peripheral revascularization, heart failure hospitalization, and all-cause mortality.

Results

Over 5 years of follow-up, 63 patients (18%) met the primary outcome. Vascular calcification was common in this cohort (median 68 years of age), with 214 patients (60%) having coronary calcification and 296 patients (84%) having aortic calcification. Older patients had greater coronary and aortic calcification, and also higher rate of MACE. In adjusted models for age and diabetes, coronary calcification was associated with higher rate of MACE (hazard ratio [HR] 2.1, interquartile range [IQR] 1.1–4.0, p=0.02) while aortic calcification was not (HR 2.7, IQR 0.8–9.0, p=0.12). Undifferentiated vascular calcification was not associated with MACE (p=0.24).

Conclusions

Coronary calcification on non-gated CT scan is independently associated with MACE in men with recurrent prostate cancer while aortic calcification is not. The presence of coronary calcification should be included in staging PET/CT reports, and this information should prompt implementation of cardiovascular risk modification strategies.

Funding Acknowledgement

Type of funding sources: Private hospital(s). Main funding source(s): This study was supported by the Mentors in Medicine Program, Department of Internal Medicine, Washington University School of Medicine.

Strong and Elastic Membranes via Hydrogen Bonding Directed Self-Assembly of Atomically Precise Nanoclusters

2D nanomaterials have provided an extraordinary palette of mechanical, electrical, optical, and catalytic properties. Ultrathin 2D nanomaterials are classically produced via exfoliation, delamination, deposition, or advanced synthesis methods using a handful of starting materials. Thus, there is a need to explore more generic avenues to expand the feasibility to the next generation 2D materials beyond atomic and molecular-level covalent networks. In this context, self-assembly of atomically precise noble nanoclusters can, in principle, suggest modular approaches for new generation 2D materials, provided that the ligand engineering allows symmetry breaking and directional internanoparticle interactions. Here the self-assembly of silver nanoclusters (NCs) capped with p-mercaptobenzoic acid ligands (Na₄ Ag₄₄ -pMBA₃₀ ) into large-area freestanding membranes by trapping the NCs in a transient solvent layer at air-solvent interfaces is demonstrated. The patchy distribution of ligand bundles facilitates symmetry breaking and preferential intralayer hydrogen bondings resulting in strong and elastic membranes. The membranes with Young's modulus of 14.5 ± 0.2 GPa can readily be transferred to different substrates. The assemblies allow detection of Raman active antibiotic molecules with high reproducibility without any need for substrate pretreatment.

Role of Zinc Oxide in the Compounding Formulation on the Growth of Nonstoichiometric Copper Sulfide Nanostructures at the Brass-Rubber Interface

Tire technology has evolved substantially by the introduction of brass-coated steel cords (BCSCs) in radial tires. The durability of radial tires is dependent on the integrity of the brass-rubber interface composed predominantly of nonstoichiometric copper sulfide (Cu_2-x S, where x = 1 to 2) nanostructures whose morphology and characteristics are dependent upon the crucial rubber additive, ZnO. Its higher concentration impacts environmental sustainability, while at lower levels, there is insufficient bonding between steel and the rubber thus affecting tire's safety. This brings in the need for an optimum ZnO concentration to be used in radial tires and is thus the theme of the present work. The changes in the properties of interfacial nanostructures such as morphology, thickness, crystallinity, and chemical composition were studied at various ZnO concentrations. We adopted our previously reported methodology, the "brass mesh experiment", to investigate the thickness of nanostructures at varied ZnO concentrations using transmission electron microscopy (TEM). Significant results were obtained from field-emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), Raman imaging and X-ray photoelectron spectroscopy (XPS). In conjunction with a more practical experimental technique, namely the measurement of pull-out force (POF), it has been concluded that 9 parts per hundred rubber (PHR) ZnO is essential for the optimum growth of nanostructures and is considered to be the optimum for the composition studied. We believe that the scientific approach outlined in the manuscript would help the tire- and the material science communities to widen the knowledge of understanding sustainability in tire industries. It is estimated that the optimization presented here can save $400-450 million for the tire industry and 2.4 million tons of ZnO per year.

Hierarchical Assembly of Atomically Precise Metal Clusters as a Luminescent Strain Sensor

We demonstrate the formation of a versatile luminescent organo-inorganic layered hybrid material, composed of bovine serum albumin (BSA)-protected Au₃₀ clusters and aminoclay sheets. X-ray diffraction revealed the intercalation of Au₃₀@BSA in the layered superstructure of aminoclay sheets. Coulombic attraction of the clusters and the clay initiates the interaction, and the appropriate size of the clusters allowed them to intercalate within the lamellar aminoclay galleries. Electron microscopy measurements confirmed the hierarchical structure of the material and also showed the cluster-attached clay sheets. Zeta potential measurement and dynamic light scattering probed the gradual formation of the ordered aggregates in solution. The hybrid material could be stretched up to 300% without fracture. The emergence of a new peak in the luminescence spectrum was observed during the course of mechanical stretching. This peak increased in intensity gradually with the degree of elongation or strain of the material. A mechanochromic luminescence response was further demonstrated with a writing experiment on a luminescent mat of the material, made by electrospinning.

Effect of varying time intervals between fentanyl and propofol administration on propofol requirement for induction of anaesthesia: Randomised controlled trial

Background and Aims:

Administration of fentanyl before induction of anaesthesia with propofol should facilitate smooth induction, with a reduction in induction dose of propofol and its side effects. This study was designed to examine the effect of varying intervals between fentanyl and propofol administration on the dose of propofol required for induction of anaesthesia.

Methods:

After institutional ethical clearance, 129 American Society of Anesthesiologists physical status I--II patients, aged 18--65 years, undergoing elective surgery under general anaesthesia were randomised into three groups. Fentanyl 2 mcg/kg was administered immediately prior to, 3 and 5 min before induction with propofol in Groups 1, 2, and 3, respectively. Requirement of propofol induction dose and haemodynamic parameters was recorded. Statistical analysis was performed using software SPSS (SPSS Inc., Chicago, Illinois, USA).

Results:

Total dose of propofol required for induction was highest in Groups 1 and lowest Group 3 (Group 1 vs. 2 vs. 3: 86.28 ± 21.12 vs. 71.67 ± 21.68 vs. 59.98 ± 20.35 mg, P < 0.00001). Dose of propofol required per kg body weight was significantly higher in Group 1 (1.41 ± 0.34 mg/kg) compared to both Group 2 (1.14 ± 0.38 mg/kg) and Group 3 (0.97 ± 0.32 mg/kg) (P < 0.00001). Incidence of hypotension during induction was significantly lower in Group 3 (14%) and Group 2 (17.1%) than in Group 1 (35.6%; P = 0.03).

Conclusion:

Administering fentanyl 5 min prior to propofol causes marked reduction in the dose requirement of the latter along with a significantly decreased incidence of hypotension during induction.

Noninvasive Ventilation and Oxygen Therapy after Extubation in Patients with Acute Respiratory Failure: A Meta-analysis of Randomized Controlled Trials

Background

Role of noninvasive ventilation (NIV) following extubation in patients with acute respiratory failure is debatable. NIV may provide benefit in post surgical patients, but its role in nonsurgical patients is controversial.

Materials and methods

PubMed and Cochrane Central Register of Controlled Trials (CENTRAL) were searched (from 1946 to 20^th November 2017) to identify prospective randomized controlled trials, where postextubation NIV has been compared with standard oxygen therapy in adult patients with acute respiratory failure.

Results

Data of 1525 patients from 11 randomized trials have been included in this meta-analysis. Two trials used NIV to manage post-extubation respiratory failure. Pooled analysis found that mortality rate at longest available follow-up [OR (95% CI) 0.84 (0.50, 1.42); p = 0.52] and reintubation rate [OR (95% CI) 0.75 (0.51, 1.09); p = 0.13] were similar between NIV and standard oxygen therapy. NIV did not decrease intubation rate when used as preventive modality [OR (95% CI) 0.65 (0.40, 1.06); p = 0.08]. Duration of ICU stay was also similar in the two groups [MD (95% CI) 0.46 (-0.43, 1.36) days; p = 0.3].

Conclusion

Post extubation NIV in non- surgical patients with acute respiratory failure does not provide any benefit over conventional oxygen therapy.

How to cite this article

Maitra S, Bhattacharjee S, Som A. Noninvasive Ventilation and Oxygen Therapy after Extubation in Patients with Acute Respiratory Failure: A Meta-analysis of Randomized Controlled Trials. Indian J Crit Care Med 2019;23(9):414-422.

Holey MoS2 Nanosheets with Photocatalytic Metal Rich Edges by Ambient Electrospray Deposition for Solar Water Disinfection

A new method for creating nanopores in single-layer molybdenum disulfide (MoS2) nanosheets (NSs) by the electrospray deposition of silver ions on a water suspension of the former is introduced. Electrospray-deposited silver ions react with the MoS2 NSs at the liquid-air interface, resulting in Ag2S nanoparticles which enter the solution, leaving the NSs with holes of 3-5 nm diameter. Specific reaction with the S of MoS2 NSs leads to Mo-rich edges. Such Mo-rich defects are highly efficient for the generation of active oxygen species such as H2O2 under visible light which causes efficient disinfection of water. 105 times higher efficiency in disinfection for the holey MoS2 NSs in comparison to normal MoS2 NSs is shown. Experiments are performed with multiple bacterial strains and a virus strain, demonstrating the utility of the method for practical applications. A conceptual prototype is also presented.

Prophylactic amiodarone vs dronedarone for prevention of perioperative arrhythmias in offpump coronary artery bypass grafting: A pilot randomized controlled trial

The aim of this study was to compare the effects of prophylactic dronedarone and amiodarone in prevention of arrhythmias during and following off-pump coronary artery bypass grafting (OPCAB). This randomized, controlled, double-blinded, parallel-group study was carried out on 36 adult male patients aged 30-70 years, with modified Parsonnet score 0-10 undergoing offpump coronary artery bypass grafting. After obtaining approval from the institutional ethics committee and informed consent, the patients were randomly allocated to two equal groups (n=18). In one group, patients were given inj. amiodarone 3mg/kg in 100ml of normal saline prior to skin incision intravenously over 20 minutes. In the second group patients received tablet dronedarone 400mg orally twice daily, commencing three days prior to the date of surgery. Patients in the amiodarone group received placebo tablet while patients in the dronedarone group received placebo infusion for the sake of blinding. The frequency and profile of arrhythmias intraoperatively and 24 hours postoperatively were studied. Intraoperative arrhythmias occurred in 50% of patients receiving amiodarone and 16.67% of patients receiving dronedarone. Maximum ventricular rate during atrial fibrillation was significantly lower in the dronedarone group (121 beats per min) than in the amiodarone group (168 beats per min). The study concludes that dronedarone appears to be at least as effective as amiodarone in prophylaxis of intraoperative and postoperative arrhythmias in patients undergoing OPCAB, with a better control of ventricular response.

Atomically Precise Nanocluster Assemblies Encapsulating Plasmonic Gold Nanorods

The self-assembled structures of atomically precise, ligand-protected noble metal nanoclusters leading to encapsulation of plasmonic gold nanorods (GNRs) is presented. Unlike highly sophisticated DNA nanotechnology, this strategically simple hydrogen bonding-directed self-assembly of nanoclusters leads to octahedral nanocrystals encapsulating GNRs. Specifically, the p-mercaptobenzoic acid (pMBA)-protected atomically precise silver nanocluster, Na₄ [Ag₄₄ (pMBA)₃₀ ], and pMBA-functionalized GNRs were used. High-resolution transmission and scanning transmission electron tomographic reconstructions suggest that the geometry of the GNR surface is responsible for directing the assembly of silver nanoclusters via H-bonding, leading to octahedral symmetry. The use of water-dispersible gold nanoclusters, Au_≈250 (pMBA)_n and Au₁₀₂ (pMBA)₄₄ , also formed layered shells encapsulating GNRs. Such cluster assemblies on colloidal particles are a new category of precision hybrids with diverse possibilities.

Self-propagated combustion synthesis of few-layered graphene: an optical properties perspective

This paper describes a labour efficient and cost-effective strategy to prepare few-layered of reduced graphene oxide like (RGOL) sheets from graphite. The self-propagated combustion route enables the bulk production of RGOL sheets. Microscopic and spectroscopic analyses confirmed the formation of few-layer graphene sheets of an average thickness of ∼3 nm and the presence of some oxygen functional groups with a C/O ratio of 8.74. A possible mechanistic pathway for the formation of RGOL sheets is proposed. The optical properties of the RGOL sample were studied in detail by means of Spectroscopic Ellipsometry (SE). The experimental abilities of SE in relating the optical properties with the number of oxygen functionalities present in the samples are explored. The data were analysed by a double-layered optical model along with the Drude-Lorentz oscillatory dispersion relation. The refractive index (n = 2.24), extinction coefficient (k = 2.03), and dielectric functions are obtained using point-by-point analysis and are also checked for Kramers-Kronig (KK) consistency.

Accuracy of quick Sequential Organ Failure Assessment (qSOFA) score and systemic inflammatory response syndrome (SIRS) criteria for predicting mortality in hospitalized patients with suspected infection: a meta-analysis of observational studies

OBJECTIVE

To identify sensitivity, specificity and predictive accuracy of quick sequential organ failure assessment (qSOFA) score and systemic inflammatory response syndrome (SIRS) criteria to predict in-hospital mortality in hospitalized patients with suspected infection.

METHODS

This meta-analysis followed the Meta-analysis of Observational Studies in Epidemiology (MOOSE) group consensus statement for conducting and reporting the results of systematic review. PubMed and EMBASE were searched for the observational studies which reported predictive utility of qSOFA score for predicting mortality in patients with suspected or proven infection with the following search words: 'qSOFA', 'q-SOFA', 'quick-SOFA', 'Quick Sequential Organ Failure Assessment', 'quick SOFA'. Sensitivity, specificity, area under receiver operating characteristic (ROC) curves with 95% confidence interval (CI) of qSOFA and SIRS criteria for predicting in-hospital mortality was collected for each study and a 2 × 2 table was created for each study.

RESULTS

Data of 406 802 patients from 45 observational studies were included in this meta-analysis. Pooled sensitivity (95% CI) and specificity (95% CI) of qSOFA ≥2 for predicting mortality in patients who were not in an intensive care unit (ICU) was 0.48 (0.41-0.55) and 0.83 (0.78-0.87), respectively. Pooled sensitivity (95% CI) of qSOFA ≥2 for predicting mortality in patients (both ICU and non-ICU settings) with suspected infection was 0.56 (0.47-0.65) and pooled specificity (95% CI) was 0.78 (0.71-0.83).

CONCLUSION

qSOFA has been found to be a poorly sensitive predictive marker for in-hospital mortality in hospitalized patients with suspected infection. It is reasonable to recommend developing another scoring system with higher sensitivity to identify high-risk patients with infection.

Rapid reaction of MoS2 nanosheets with Pb2+ and Pb4+ ions in solution

Understanding the chemical changes happening to nanostructures during a process is vital in selecting them for applications. Here, we investigated the difference in the reactivity of the bulk and nanoscale forms of molybdenum disulfide (MoS₂) in solution with lead ions (Pb²⁺ and Pb⁴⁺) as probes, at room temperature. While the bulk form did not show any reactivity in the experimental timescale, the two-dimensional (2D) nanoscale form showed not only reactivity but also quite rapid kinetics that resulted in the formation of distinct products, principally PbMoO₄ with anion substitution, in a few seconds. Depending on the charge state of the cation, and the pH of the reaction mixture, two different kinds of morphologies of the same reaction product were formed. Furthermore, we demonstrate that this unusual reactivity of the MoS₂ nanosheets (NSs) was retained in its supported form and hence, such supported materials can be effective for the abstraction of toxic lead from water, with fast kinetics.

Interparticle Reactions: An Emerging Direction in Nanomaterials Chemistry

Nanoparticles exhibit a rich variety in terms of structure, composition, and properties. However, reactions between them remain largely unexplored. In this Account, we discuss an emerging aspect of nanomaterials chemistry, namely, interparticle reactions in solution phase, similar to reactions between molecules, involving atomically precise noble metal clusters. A brief historical account of the developments, starting from the bare, gas phase clusters, which led to the synthesis of atomically precise monolayer protected clusters in solution, is presented first. Then a reaction between two thiolate-protected, atomically precise noble metal clusters, [Au₂₅(PET)₁₈]^- and [Ag₄₄(FTP)₃₀]^4- (PET = 2-phenylethanethiol, FTP = 4-fluorothiophenol), is presented wherein these clusters spontaneously exchange metal atoms, ligands, and metal-ligand fragments between them under ambient conditions. The number of exchanged species could be controlled by varying the initial compositions of the reactant clusters. Next, a reaction of [Au₂₅(PET)₁₈]^- with its structural analogue [Ag₂₅(DMBT)₁₈]^- (DMBT = 2,4-dimethylbenzenethiol) is presented, which shows that atom-exchange reactions happen with structures conserved. We detected a transient dianionic adduct, [Ag₂₅Au₂₅(DMBT)₁₈(PET)₁₈]^2-, formed between the two clusters indicating that this adduct could be a possible intermediate of the reaction. A reaction involving a dithiolate-protected cluster, [Ag₂₉(BDT)₁₂]^3- (BDT = 1,3-benzenedithiol), is also presented wherein metal atom exchange alone occurs, but with no ligand and fragment exchanges. These examples demonstrate that the nature of the metal-thiolate interface, that is, its bonding network and dynamics, play crucial roles in dictating the type of exchange processes and overall rates. We also discuss a recently proposed structural model of these clusters, namely, the Borromean ring model, to understand the dynamics of the metal-ligand interfaces and to address the site specificity and selectivity in these reactions. In the subsequent sections, reactions involving atomically precise noble metal clusters and one- and two-dimensional nanosystems are presented. We show that highly protected, stable clusters such as [Au₂₅(PET)₁₈]^- undergo chemical transformation on graphenic surfaces to form a bigger cluster, Au₁₃₅(PET)₅₇. Finally, we present the transformation of tellurium nanowires (Te NWs) to Ag-Te-Ag dumbbell nanostructures through a reaction with an atomically precise silver cluster, Ag₃₂(SG)₁₉ (SG = glutathione thiolate). The starting materials and the products were characterized using high resolution electrospray ionization mass spectrometry, matrix assisted laser desorption ionization mass spectrometry, UV/vis absorption, luminescence spectroscopies, etc. We have analyzed principally mass spectrometric data to understand these reactions. In summary, we present the emergence of a new branch of chemistry involving the reactions of atomically precise cluster systems, which are prototypical nanoparticles. We demonstrate that such interparticle chemistry is not limited to metal clusters; it occurs across zero-, one-, and two-dimensional nanosystems leading to specific transformations. We conclude this Account with a discussion of the limitations in understanding of these reactions and future directions in this area of nanomaterials chemistry.

Ultra-high sensitivity infra-red detection and temperature effects in a graphene-tellurium nanowire binary hybrid

The optoelectronic performance of hybrid devices from graphene and optically sensitive semiconductors exceeds conventional photodetectors due to a large in-built optical gain. Tellurium nanowire (TeNW), being a narrow direct band gap semiconductor (∼0.65 eV), is as an excellent potential candidate for near infra-red (NIR) detection. Here we demonstrate a new graphene-TeNW binary hybrid that exhibits a maximum photoresponsivity of ∼10⁶ A W^-1 at 175 K in the NIR regime (920 nm-1720 nm), which exceeds the photoresponsivity of the most common NIR photodetectors. The resulting noise-equivalent power (NEP) is as low as 2 × 10^-18 W Hz^-1/2, and the specific detectivity (D*) exceeds 5 × 10¹³ cm Hz^1/2 W^-1 (Jones). The temperature range of optimal operation, which extends up to ≈220 K and ≈260 K for 1720 nm and 920 nm excitation, respectively, is primarily limited by the electrical conductivity of the TeNW layer, and can further be improved by lowering of the defect density as well as inter-wire electronic coupling.

[Perioperative gabapentin and pregabalin in cardiac surgery: a systematic review and meta-analysis]

OBJECTIVES

Sternotomy for cardiac surgeries causes significant postoperative pain and when not properly managed may cause significant morbidity. As neuropathic pain is a significant component here, gabapentin and pregabalin may be effective in these patients and may reduce postoperative opioid consumption. The purpose of this systematic review was to find out efficacy of gabapentin and pregabalin in acute postoperative pain after cardiac surgery.

METHODS

Published prospective human randomized clinical trials, which compared preoperative and/or postoperative gabapentin/pregabalin with placebo or no treatment for postoperative pain management after cardiac surgery has been included in this review.

RESULTS

Four RCTs each for gabapentin and pregabalin have been included in this systematic review. Three gabapentin and two pregabalin studies reported decrease in opioid consumption in cardiac surgical patients while one gabapentin and two pregabalin studies did not. Three RCTs each for gabapentin and pregabalin reported lower pain scores both during activity and rest. The drugs are not associated with any significant complications.

CONCLUSION

Despite lower pain scores in the postoperative period, there is insufficient evidence to recommend routine use of gabapentin and pregabalin to reduce opioid consumption in the cardiac surgical patients.

Confined Metastable 2-Line Ferrihydrite for Affordable Point-of-Use Arsenic-Free Drinking Water

Arsenic-free drinking water, independent of electrical power and piped water supply, is possible only through advanced and affordable materials with large uptake capacities. Confined metastable 2-line ferrihydrite, stable at ambient temperature, shows continuous arsenic uptake in the presence of other complex species in natural drinking water and an affordable water-purification device is made using the same.

Goal directed fluid therapy decreases postoperative morbidity but not mortality in major non-cardiac surgery: a meta-analysis and trial sequential analysis of randomized controlled trials

BACKGROUND AND AIMS

Optimum perioperative fluid administration may improve postoperative outcome after major surgery. This meta-analysis and systematic review has been aimed to determine the effect of dynamic goal directed fluid therapy (GDFT) on postoperative morbidity and mortality in non-cardiac surgical patients.

MATERIAL AND METHODS

Meta-analysis of published prospective randomized controlled trials where GDFT based on non-invasive flow based hemodynamic measurement has been compared with a standard care. Data from 41 prospective randomized trials have been included in this study.

RESULTS

Use of GDFT in major surgical patients does not decrease postoperative hospital/30-day mortality (OR 0.70, 95 % CI 0.46-1.08, p = 0.11) length of post-operative hospital stay (SMD -0.14; 95 % CI -0.28, 0.00; p = 0.05) and length of ICU stay (SMD -0.12; 95 % CI -0.28, 0.04; p = 0.14). However, number of patients having at least one postoperative complication is significantly lower with use of GDFT (OR 0.57; 95 % CI 0.43, 0.75; p < 0.0001). Abdominal complications (p = 0.008), wound infection (p = 0.002) and postoperative hypotension (p = 0.04) are also decreased with used of GDFT as opposed to a standard care. Though patients who received GDFT were infused more colloid (p < 0.0001), there is no increased risk of heart failure or pulmonary edema and renal failure.

CONCLUSION

GDFT in major non- cardiac surgical patients has questionable benefit over a standard care in terms of postoperative mortality, length of hospital stay and length of ICU stay. However, incidence of all complications including wound infection, abdominal complications and postoperative hypotension is reduced.

Unusual reactivity of MoS2 nanosheets

The reactivity of the 2D nanosheets of MoS2 with silver ions in solution, leading to their spontaneous morphological and chemical transformations, is reported. This unique reactivity of the nanoscale form of MoS2 was in stark contrast to its bulk counterpart. While the gradual morphological transformation involving several steps has been captured with an electron microscope, precise chemical identification of the species involved was achieved by electron spectroscopy and mass spectrometry. The energetics of the system investigated supports the observed chemical transformation. The reaction with mercury and gold ions shows similar and dissimilar reaction products, respectively and points to the stability of the metal-sulphur bond in determining the chemical compositions of the final products.

Cluster-Mediated Crossed Bilayer Precision Assemblies of 1D Nanowires

Highly organized crossed bilayer assemblies of nanowires (NWs) are made using directed hydrogen bonding between the protecting ligand shells of atomically precise cluster molecules anchored on NWs. Layers of quantum clusters remain sandwiched between two neighboring NWs at a defined distance, dictated by the core-size of the cluster, while the orientation of the ligands in space dictates the interlayer geometry.

Metallic Nanobrushes Made using Ambient Droplet Sprays

An ambient solution-state method for making uniform nanobrushes composed of oriented 1D silver nanowires (NWs) with aspect ratios of 10(2) -10(4) is reported. These structures are grown over cm(2) areas on conducting surfaces. Assemblies of NWs form uniform nanobrush structures, which can capture micrometer-sized objects, such as bacteria and particulate matter. Variation in composition produces unique structures with catalytic properties.

Ambient solid-state mechano-chemical reactions between functionalized carbon nanotubes

Carbon nanotubes can be chemically modified by attaching various functionalities to their surfaces, although harsh chemical treatments can lead to their break-up into graphene nanostructures. On the other hand, direct coupling between functionalities bound on individual nanotubes could lead to, as yet unexplored, spontaneous chemical reactions. Here we report an ambient mechano-chemical reaction between two varieties of nanotubes, carrying predominantly carboxyl and hydroxyl functionalities, respectively, facilitated by simple mechanical grinding of the reactants. The purely solid-state reaction between the chemically differentiated nanotube species produces condensation products and unzipping of nanotubes due to local energy release, as confirmed by spectroscopic measurements, thermal analysis and molecular dynamic simulations.

Response in bone turnover markers during therapy predicts overall survival in patients with metastatic prostate cancer: analysis of three clinical trials

Background:

The bone-forming metastases of prostate cancer result from complex stromal–epithelial interactions within the tumour microenvironment. Autocrine–paracrine signalling pathways between prostate cancer epithelial cells, osteoblasts, and osteoclasts stimulate aberrant bone remodelling, and the activity of these three cell populations can be quantitatively measured using prostate-specific antigen (PSA), bone-specific alkaline phosphatase (BAP) and urine N-telopeptide (uNTx), respectively. The purpose of the present study was to test the hypothesis that serial measurements of BAP and uNTx during therapy would facilitate monitoring of disease activity and predict the overall survival (OS) in patients with metastatic prostate cancer receiving therapy.

Methods:

Radionuclide bone scan, PSA, BAP, and uNTx data were retrospectively analysed from three clinical trials in patients with metastatic prostate cancer conducted at our institution. Qualitative changes in bone scans and quantitative changes in PSA, BAP, and uNTx concentrations during therapy were correlated with OS.

Results:

Baseline levels of BAP, but not PSA, were prognostic for OS in both androgen-dependent and castrate-resistant disease. A reduction in PSA, BAP, uNTx, or BAP/uNTx on therapy was predictive of improved OS in both patient groups. Conversely, an increase in PSA, or BAP on therapy was predictive of worse OS in both patient groups. Baseline number of lesions and response on bone scan during therapy were neither prognostic nor predictive of OS in either patient group.

Conclusion:

These observations support the concept that serial measurements of bone turnover metabolites during therapy function as clinically informative predictive biomarkers in patients with advanced prostate cancer and skeletal metastases. PSA measurements and bone scans remain essential to monitor the overall disease activity and determine the anatomic distribution of skeletal metastases.

Heterojunction double dumb-bell Ag₂Te-Te-Ag₂Te nanowires

Growth of isolated axial heterojunction nanowires by a solution phase growth process is reported. The dumb-bell shaped nanowires contain two silver telluride sections at the extremes joined by a tellurium section. Reaction of silver nitrate with tellurium NWs in aqueous solution at a molar ratio of 1 : 1 leads to the formation of amorphous partially silver reacted Te NWs. Low temperature (75 °C) solution phase annealing of these silver deficient NWs results in phase segregation producing crystalline Ag(2)Te and Te phases with clear phase boundaries along the wire axis. Structural characterization of these dumb-bell shaped NWs was performed with different microscopic and spectroscopic tools. Solution phase silver concentration over the course of annealing indicated leaching of silver into the solution during the formation of biphasic NWs. Similar Ag : Te ratios were observed in both partially silver reacted Te NWs and phase segregated Ag(2)Te-Te-Ag(2)Te NWs and this was attributed to redeposition of leached silver on the amorphous NW tips which eventually resulted in complete phase segregation. Successful integration of different chemical components in single NWs is expected to open up new application possibilities as physical and chemical properties of the heterostructure can be exploited.

Coding DNA sequences: statistical distributions

The base distributions in coding DNA sequences (CDS) are investigated. We explore the scaling properties of the 4-dimensional directed random walk and compare them with that for the DNA sequences. Inference from these observation are, however, contradicted by alternate analysis using factorial moments. To resolve this conflict we look directly at the nucleotide base distributions. In all the cases the base distributions change from gaussian to non-gaussian as the scale size is increased. The CDS, therefore, have nucleotide distributions different from the random.

Codon distributions in DNA

The codons, 64 in number, are distributed over the coding parts of DNA sequences. The distribution function is the plot of frequency versus rank of the codons. These distributions are characterized by parameters that are almost universal, i.e., gene independent. There is but a small part that depends on the gene. We present the theory to calculate the universal (gene-independent) part. The part that is gene-specific, however, has undetermined overlaps and fluctuations.

Identification of human proteins using the linguist's tools

The symbolic sequences of the exons that make human proteins are subjected to methods of statistical linguistics. The ideas developed for the natural languages by G. K. Zipf, when applied to these sequences, show significant promise. In particular, we argue, the Zipf's exponent differentiates, and hence, identifies disparate human sequences.