Hydrothermal synthesis of rGO and MnCoS composite for enhanced supercapacitor application

Nanostructured materials incorporating transition metal sulfides have demonstrated considerable potential across various applications, particularly in the realms of energy production and storage. Sulfide-based material preparation is a challenging and costly procedure that requires a high temperature and reducing atmosphere. This work reports that manganese cobalt sulfide (MCS) and reduced graphene oxide composite manganese cobalt sulfide (rMCS) were successfully prepared through a hydrothermal method. Various characterization techniques were employed to analyze the prepared materials, including X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, Brunauer-Emmett-Teller analysis, and X-ray photoelectron spectroscopy. In a three-electrode system, MCS and rMCS electrodes exhibit an excellent specific capacitance of 1695 and 1925 F g-1 at 1 A g-1 current density respectively. MCS delivers the capacitance retention of 99% and rMCS exhibits the capacitance retention of 100% capacitance retention over 5000 consecutive cycles. The constructed asymmetric supercapacitor electrode (rMCS//rGO) exhibits the energy and power density of 64 Wh kg-1 at 799 W kg-1, respectively with outstanding cyclic stability of 97.4% even after 10,000 cycles. The exceptional electrochemical properties of MCS with rGO composite electrode indicate that they would make an outstanding electrode material for cutting-edge energy storage devices.

A review of the role of graphene-based nanomaterials in tackling challenges posed by the COVID-19 pandemic

In 2020, the World Health Organization (WHO) declared a pandemic due to the emergence of the coronavirus disease (COVID-19) which had resulted by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). At present, the emergence of many new variants and mutants were found to be more harmful compared to the previous strains. As a result, research scientists around the world had devoted significant efforts to understand the mechanism, causes and transmission due to COVID-19 along with the treatment to cure these diseases. However, despite achieving several findings, much more was unknown and yet to be explored. Hence, along with these developments, it is also extremely essential to design effective systems by incorporating smart materials to battle the COVID-19. Therefore, several approaches have been implemented to combat against COVID-19. Recently, the graphene-based materials have been explored for the current COVID-19 and future pandemics due to its superior physicochemical properties, providing efficient nanoplatforms for optical and electrochemical sensing and diagnostic applications with high sensitivity and selectivity. Moreover, based on the photothermal effects or reactive oxygen species formation, the carbon-based nanomaterials have shown its potentiality for targeted antiviral drug delivery and the inhibitory effects against pathogenic viruses. Therefore, this review article sheds light on the recent progress and the most promising strategies related to graphene and related materials and its applications for detection, decontamination, diagnosis, and protection against COVID-19. In addition, the key challenges and future directives are discussed in detail for fundamental design and development of technologies based on graphene-based materials along with the demand aspects of graphene-based products and lastly, our personal opinions on the appropriate approaches to improve these technologies respectively.

Anti-Inflammatory Potential of Costus speciosus rhizome Bioactive Phytochemicals: A Combined GC-MS and Computational Approach Targeting TLR-4 Signaling

BACKGROUND

Plants represent a rich reservoir of bioactive compounds with established therapeutic value in diverse diseases. Notably, the Toll-like receptor-4 (TLR-4) signaling pathway plays a pivotal role in inflammation. Upon engagement with pro-inflammatory ligands like lipopolysaccharide, TLR-4 triggers downstream cascades involving nuclear factor ĸappa B and mitogen- activated protein kinases. This signaling cascade ultimately dictates the onset and progression of inflammatory diseases. Therefore, targeting TLR-4 signaling offers a promising therapeutic approach for managing inflammatory disorders.

METHODS

This study investigated the potential of Costus speciosus rhizome phytocompounds, a traditional medicinal plant, as novel as modulators of TLR-4 signaling, highlighting their mechanisms of action and potential clinical applications. In the present study, 18 phytocompounds isolated from the rhizome of Costus speciosus, were studied against TLR-4/AP-1 signaling, which is implicated in the inflammatory process using a computational approach.

RESULTS

The compounds exhibited binding affinities ranging from -4.087 to -8.93 kcal/mol with the TLR-4 protein due to the formation of multiple intermolecular interactions. Benzenepropanoic acid, 3,5-bis(1,1-dimethylethyl)-4-hydroxy-, methyl ester (compound 7) exhibited exceptional binding energy (-8.93 kcal/mol), indicating strong affinity for the TLR-4 protein. Additionally, compound 7 displayed favorable ADMET properties, suggesting promising drug development potential. Molecular dynamics simulations confirmed the stability of the compound 7-TLR4 complex, further supporting its ability to modulate TLR-4 signaling.

CONCLUSION

These findings highlight the therapeutic potential of Costus speciosus phytocompounds, particularly compound 7, as potent anti-inflammatory modulators. Further research is warranted to validate their anti-inflammatory and neuroprotective effects in pre-clinical models, paving the way for their development as novel therapeutic agents for inflammatory diseases.

Designing nano-heterostructured nickel doped tin sulfide/tin oxide as binder free electrode material for supercapattery

New generation of electrochemical energy storage devices (EESD) such as supercapattery is being intensively studied as it merges the ideal energy density of batteries and optimal power density of supercapacitors in a single device. A multitude of parameters such as the method of electrodes preparation can affect the performance of supercapattery. In this research, nickel doped tin sulfide /tin oxide (SnS@Ni/SnO2) heterostructures were grown directly on the Ni foam and subjected to different calcination temperatures to study their effect on formation, properties, and electrochemical performance through X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and electrochemical tests. The optimized SnS@Ni/SnO2 electrode achieved a maximum specific capacity of 319 C g- 1 while activated carbon based capacitive electrode exhibited maximum specific capacitance of 381.19 Fg- 1. Besides, capacitive electrodes for the supercapattery were optimized by incorporating different conductive materials such as acetylene black (AB), carbon nanotubes (CNT) and graphene (GR). Assembling these optimized electrodes with the aid of charge balancing equation, the assembled supercapattery was able to achieve outstanding maximum energy density and power density of 36.04 Wh kg- 1 and 12.48 kW kg- 1 with capacity retention of 91% over 4,000 charge/discharge cycles.

Evaluation of rabi season sesame productivity from graded nutrient doses and tillage regimes in rice fallows of southern plateau and hills region of the Indian sub-continent

Background

Only scattered information is available on the tillage and nutrient management information for the sesame crop following rice in the literature. Sesame as an edible oil yielding crop with high levels of unsaturated fatty acids has high international demand due to superior health benefits. Being a small seeded crop, it requires standard tillage and nutrient management to obtain optimum productivity under rice fallow ecologies. As a sequential crop after rice harvest, the tillage and nutrient management practices followed for the preceding rice have astounding effects on the succeeding sesame crop. To better understand and manipulate the agro ecology in the rice fallow culture, it is necessary to study the behaviour of sesame cultivars, in relation to the tillage requirements and macro nutrient factors that have a bearing on the productivity.

Methods

The aim of this work was to evaluate the productivity of rice fallow sesame in the southern plateau and hills regions of the Indian sub-continent (Tamil Nadu) with a hypothesis that tillage and nutrient management would immensely benefit the sesame crop. Field experiments were conducted at TNAU, Tamil Nadu Rice Research Institute, Aduturai, Tamil Nadu during 2019-2020 and 2020-2021 with tillage practices (reduced tillage, conventional tillage and zero tillage) and fertilizer doses (zero percent RDF, 25% RDF, 50% RDF, 75% RDF and 100% RDF) in a split plot design replicated thrice.

Results

The results have clearly indicated that the performance of rice fallow sesame was poor under zero till conditions as the sesame crop is poorly adapted leading to a yield penalty up to 68%. A total of 75% RDF has yielded statistically similar yield to that of 100% RDF to the rice fallow sesame. Further, neither the oil content nor the fatty acid composition was modified by tillage and nutrient management regimes.

High-Performance Sodium-Ion Batteries with Graphene: An Overview of Recent Developments and Design

Due to their low production cost, sodium-ion batteries (SIBs) are considered attractive alternatives to lithium-ion batteries (LIBs) for next generation sustainable and large-scale energy storage systems. However, during the charge/discharge cycle, a large volume strain is resulted due to the presence of a large radius of sodium ions and high molar compared to lithium ions, which further leads to poor cyclic stability and lower reversible capacity. In the past, researchers have devoted significant efforts to explore various anode materials to achieve SIBs with high energy density. Hence, as a promising anode material for SIBs, the two-dimensional (2D) materials including graphene and its derivatives and metal oxides have attracted remarkable attention due to their layered structure and superior physical and chemical properties. The inclusion of graphene and metal oxides with other nanomaterials in electrodes have led to the significant enhancements in electrical conductivity, reaction kinetics, capacity, rate performance and accommodating the large volume change respectively. Moreover, these 2D materials facilitated large surface areas and shorter paths for sodium ion adsorption and transportation respectively. In this review article, the fabrication techniques, structural configuration, sodium ion storage mechanism and its electrochemical performances will be introduced. Subsequently, an insight into the recent advancements in SIBs associated with 2D anode materials (graphene, graphene oxide (GO), transition metal oxides etc.) and other graphene-like elementary analogues (germanene, stanine etc.) as anode materials respectively will be discussed. Finally, the key challenges and future perspectives of SIBs towards enhancing the sodium storage performance of graphene-based electrode materials are discussed. In summary, we believe that this review will shed light on the path towards achieving long-cycling life, low operation cost and safe SIBs with high energy density using 2D anode materials and to be suitably commercialized for large-scale energy storage applications in the future.

Evaluation of the effect of precursor ratios on the electrochemical performances of binder-free NiMn-phosphate electrodes for supercapattery

Binary metal phosphate electrodes have been widely studied for energy storage applications due to the synergistic effects of two different transition elements that able to provide better conductivity and stability. Herein, the battery-type binder-free nickel-manganese phosphate (NiMn-phosphate) electrodes were fabricated with different Ni:Mn precursor ratios via microwave-assisted hydrothermal technique for 5 min at 90 °C. Overall, NiMn3P electrode (Ni:Mn = 1:3) showed an outstanding electrochemical performance, displaying the highest specific (areal) capacity at 3 A/g of 1262.4 C/g (0.44 C/cm2), and the smallest charge transfer resistance of 108.8 Ω. The enhanced performance of NiMn3P electrode can be ascribed to the fully grown amorphous nature and small-sized flake and flower structures of NiMn3P electrode material on the nickel foam (NF) surface. This configuration offered a higher number of active sites and a larger exposed area, facilitating efficient electrochemical reactions with the electrolyte. Consequently, the NiMn3P//AC electrode combination was chosen to further investigate its performance in supercapattery. The NiMn3P//AC supercapattery exhibited remarkable energy density of 105.4 Wh/kg and excellent cyclic stability with 84.7% retention after 3000 cycles. These findings underscored the superior electrochemical performance of the battery-type binder-free NiMn3P electrode, and highlight its potential for enhancing the overall performance of supercapattery.

MXene-Embedded Porous Carbon-Based Cu2O Nanocomposites for Non-Enzymatic Glucose Sensors

This work explores the use of MXene-embedded porous carbon-based Cu2O nanocomposite (Cu2O/M/AC) as a sensing material for the electrochemical sensing of glucose. The composite was prepared using the coprecipitation method and further analyzed for its morphological and structural characteristics. The highly porous scaffold of activated (porous) carbon facilitated the incorporation of MXene and copper oxide inside the pores and also acted as a medium for charge transfer. In the Cu2O/M/AC composite, MXene and Cu2O influence the sensing parameters, which were confirmed using electrochemical techniques such as cyclic voltammetry, electrochemical impedance spectroscopy, and amperometric analysis. The prepared composite shows two sets of linear ranges for glucose with a limit of detection (LOD) of 1.96 μM. The linear range was found to be 0.004 to 13.3 mM and 15.3 to 28.4 mM, with sensitivity values of 430.3 and 240.5 μA mM-1 cm-2, respectively. These materials suggest that the prepared Cu2O/M/AC nanocomposite can be utilized as a sensing material for non-enzymatic glucose sensors.

Evidence of a Hardening in the Cosmic Ray Proton Spectrum at around 166 TeV Observed by the GRAPES-3 Experiment

We present the measurement of the cosmic ray proton spectrum from 50 TeV to 1.3 PeV using 7.81×10^{6} extensive air shower events recorded by the ground-based GRAPES-3 experiment between 1 January 2014 and 26 October 2015 with a live time of 460 day. Our measurements provide an overlap with direct observations by satellite and balloon-based experiments. The electromagnetic and muon components in the shower were measured by a dense array of plastic scintillator detectors and a tracking muon telescope, respectively. The relative composition of the proton primary from the air shower data containing all primary particles was extracted using the multiplicity distribution of muons which is a sensitive observable for mass composition. The observed proton spectrum suggests a spectral hardening at ∼166  TeV and disfavors a single power law description of the spectrum up to the Knee energy (∼3  PeV).

Agricultural Waste-Derived Biochar-Based Nitrogenous Fertilizer for Slow-Release Applications

The exponential increase in population demands more food to be produced by employing modern technologies. There is a worldwide increase in the use of chemical fertilizers to rapidly enhance the crop yield. Nitrogen is a crucial plant nutrient, and nitrogenous fertilizers are the most widely used fertilizers. However, the high solubility and volatility of commonly used nitrogenous fertilizers have led to low nutrient use efficiency and alarming environmental pollution. They are lost due to the volatilization of ammonia and leaching of nitrate and release of nitrous oxide, and thus, plants only absorb approximately 20-30% of the nitrogen present in fertilizers. Slow-release fertilizers have been designed to overcome these issues and supply nutrients gradually and sustainably. Biochar, a solid material rich in carbon derived from biomass, can reduce nutrient loss in soil and extend the effectiveness of fertilizers in promoting plant uptake. In the present study, a slow-release nitrogenous fertilizer is prepared using biochar obtained by pyrolysis of a banana leaf sheath (BLS) at 500 °C for 3 h. The BLS biochar and nutrient-loaded BLS (NBLS) biochar exhibited significant water absorbance capacity, water retention capacity, swelling ratio, and equilibrium water content, which would support the maintenance of water levels in soils. The lower salt index values of the prepared fertilizer showed its potential to be used as a sustainable and clean fertilizer. The prepared BLS and NBLS biochar were also characterized by various techniques such as Fourier transform infrared (FT-IR), powder X-ray diffraction, thermogravimetric analysis, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Brunauer-Emmett-Teller (BET) methods. The FT-IR spectra of both BLS and NBLS biochar demonstrate the existence of primary, secondary, and tertiary alcohols, alkanes, alkenes, esters, and phenols. The peak at 1423 cm-1 in NBLS biochar corresponds to the vibration of NH4+ confirming nutrient loading. A minor phase change was noticed in the intensities of NBLS biochar, which may be attributed to the absorption of nutrients into the structure of biochar. TGA analysis confirmed the stability of BLS and NBLS Biochar. SEM analysis demonstrates a highly porous structure of the biochar samples due to the release of volatile matter from the biomass. The BET-specific surface area of BLS and NBLS biochar was 43.216 and 35.014 m2/g, respectively. Nutrient release studies showed an incremental increase in the nitrogen release percentage over a period of 16 h. The gradual supply of nitrogen to the plants over an extended period demonstrated by the prepared slow-release fertilizer confirms its potential to reduce the leaching loss commonly observed in conventional chemical fertilizers.

Analysis of the Effectiveness of 3D Printed Patient-Specific Implants for Reconstruction of Maxillary Defect Secondary to Mucormycosis

Introduction

Patients affected with mucormycosis of maxilla have been increasing following Covid-19 infections. We followed the reconstruction of the maxilla using 3D manufactured patient-specific implants. The additive manufacturing technology is capable of fabricating custom-made titanium implants precisely for oral and maxillofacial reconstructions.

Aim

To analyse the effectiveness of 3D manufactured patient-specific implants in the reconstruction of maxilla affected by mucormycosis secondary to Covid-19. Methodology: This study was conducted among 20 patients receiving patient-specific implants for surgical and prosthetic reconstruction of the maxilla. The parameters analysed at baseline, 3 months, 6 months, and 12 months were pain, implant exposure, infection, wound dehiscence, fit of implant, postoperative surgical rating scale, and patient experience evaluation rating scale.

Results

Inferential Statistics revealed a positive correlation.

Conclusion

From the present data, it can be concluded that within the limitations of the study, patient-specific implant systems are an effective treatment strategy for the reconstruction of the maxilla affected by mucormycosis secondary to Covid-19. More studies with larger sample size and longer follow-up periods are required to substantiate the results from the present study.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12663-023-01922-7.

Fabrication and characterization of graphene oxide-based polymer nanocomposite coatings, improved stability and hydrophobicity

In this study, acrylic-epoxy-based nanocomposite coatings loaded with different concentrations (0.5-3 wt.%) of graphene oxide (GO) nanoparticles were successfully prepared via the solution intercalation approach. The thermogravimetric analysis (TGA) revealed that the inclusion of GO nanoparticles into the polymer matrix increased the thermal stability of the coatings. The degree of transparency evaluated by the ultraviolet-visible (UV-Vis) spectroscopy showed that the lowest loading rate of GO (0.5 wt.%) had completely blocked the incoming irradiation, thus resulting in zero percent transmittance. Furthermore, the water contact angle (WCA) measurements revealed that the incorporation of GO nanoparticles and PDMS into the polymer matrix had remarkably enhanced the surface hydrophobicity, exhibiting the highest WCA of 87.55º. In addition, the cross-hatch test (CHT) showed that all the hybrid coatings exhibited excellent surface adhesion behaviour, receiving 4B and 5B ratings respectively. Moreover, the field emission scanning electron microscopy (FESEM) micrographs confirmed that the presence of the functional groups on the GO surface facilitated the chemical functionalization process, which led to excellent dispersibility. The GO composition up to 2 wt.% showed excellent dispersion and uniform distribution of the GO nanoparticles within the polymer matrix. Therefore, the unique features of graphene and its derivatives have emerged as a new class of nanofillers/inhibitors for corrosion protection applications.

Structure-property relationships in critically connected (GeTe4)100-x(As2Se3)x glasses

Thermal, optical, mechanical and structural studies were carried out on glasses in the pseudo-binary joint GeTe₄-As₂Se₃ prepared by a melt quenching method. (GeTe₄)_100-x(As₂Se₃)_x glasses in the entire composition range of 0 ≤ x ≤ 100 have an average coordination number (Z_av) = 2.4, where the glass forming ability is found to be maximum. In general, for Z_av ≤ 2.4, the glass transition is found to be dominated by the network connectivity and the chemical composition effects are minimal. Although Z_av of Ge₂₀Te₈₀ (GeTe₄) and As₂Se₃ (As₄₀Se₆₀) is 2.4, GeTe₄ is a poor glass former and As₂Se₃ is an excellent glass former. The glass-forming ability is expected to increase with the addition of As₂Se₃. Surprisingly, the glass forming ability is found to decrease with the initial addition of As₂Se₃ and then shows an increasing trend. Glass transition (T_g) shows a large variation from 175 °C for x = 0 to 108 °C for x = 30. Based on the variation in the properties, the tie-line can be divided into three regions: region I (0 ≤ x ≤ 20) where T_g shows a decreasing trend, region II (25 ≤ x ≤ 55) where T_g remains almost constant and region III (60 ≤ x ≤ 100) where T_g shows an increasing trend. Hardness measurement also shows a similar trend in the three regions. Thermal stability shows a continuous increase with the increase of As₂Se₃. The fragility index varies between 15 and 30 for all these glasses except for x = 0 (GeTe₄) indicating the strong nature of the melts containing As₂Se₃. Raman studies indicate that the glassy network is dominated mainly by GeTe_(4/2) in region I and in region III the network is dominated by AsSe_(3/2) based structures. Glasses in region II are found to be dominated by AsTe_3/2 based structures. This study brings out the dominance of chemical composition effects over the network connectivity in a critically coordinated network. These glasses are also found to transmit IR light up to 18 μm and offer a wide composition range to prepare bulk glasses to be useful for infrared applications.

Coexisting good neighbours: acoustic and calling microhabitat niche partitioning in two elusive syntopic species of balloon frogs, Uperodon systoma and U. globulosus (Anura: Microhylidae) and potential of individual vocal signatures

Background

Most amphibians use a repertoire of acoustic signals to propagate signals in social contexts. The description of these repertoires provides a key towards the understanding of the behaviour of individuals and the evolutionary functions of calls. Here, we assessed the variations in advertisement calls within and between two fossorial sympatric species, Uperodon systoma and Uperodon globulosus, that share their breeding season and breeding sites. For each species, we applied Beecher’s index of total information capacity (HS) for the individual vocal signature, determined the difference in call properties and demonstrated the segregation in the calling microhabitat niche between the two species.

Results

Our results demonstrated that the advertisement calls of U. systoma are pulsatile with a call rate of 3.00 ± 0.97 calls per second while those of U. globulosus are not pulsatile with a lower call rate of 0.53 ± 0.22 calls per second. For both species, the variations in call properties among individuals was higher than that within individual, a pattern consistent with that of other fossorial anurans. The body condition and air temperature did not significantly impact the call properties of either species. The outcome of the Beecher’s index (HS) showed that the calls of U. systoma can be used to identify 14 different individuals and the calls of U. globulosus can be used to identify 26 different individuals. The statistical analyses on the advertisement call of the two species showed a significant difference in the temporal properties as the call duration, and fall time and rise time were significantly different between the two species. Lastly, we successfully demonstrated that there is a clear segregation in calling site microhabitat between the two species, where U. globulosus calls floating close to the bank of the waterbody while U. systoma calls floating further away from the bank.

Conclusion

This study highlights the potential for pre-mating isolation, character displacement and assortative mating in two syntopic fossorial anurans, leading to association between acoustic, calling microhabitat niche and body index divergence as important behavioural and ecological traits.

Robot Assisted Laparoscopic Repair of Vesicovaginal Fistula: A Retrospective Study at a Tertiary Care Centre, Chennai, India

Introduction: Vesicovaginal Fistula (VVF) is the most common acquired fistula of the urinary tract in women. Robotic surgery is recently introduced for VVF repair and has benefits over conventional methods. Aim: To describe experience with robot-assisted laparoscopic repair of VVF in patients. Materials and Methods: This was a retrospective observational study conducted from February 2014 to February 2018, at Department of Urology, Apollo Main Hospital, Chennai, Tamil Nadu, India. The study included 24 patients who underwent robot-assisted laparoscopic VVF repair. After cystoscopy ureteric catheter was passed through the fistula and retrieved through vagina. Bilateral ureteric catheters were placed simultaneously with vaginal packing. Da Vinci Si robot was docked with patient in trendelenburg position. After trocar placement transperitoneally the fistula was approached. Through vertical or transverse cystotomy, fistula was identified. With the circumferential incision around the fistula, both the bladder and vagina was separated and the fistulous tract was excised. Bladder was closed vertically and vaginal opening was closed transversely interposing the Omentum. Statistical analyses were performed using the Statistical Package for Social Sciences (SPSS) version 20.0. Results: The mean age of participants was 40.33 years. Elective hysterectomy done for benign conditions (91.67%) was the major cause of VVF in patients followed by emergency hysterectomy (8.33%). All of the patients underwent adhesiolysis while two patients performed right ureteric re-implantation additionally. The median operative time was 127.50 minutes. The median duration of drain and hospital stay was three days each. Urethral Foley’s catheter removal done at 2-3 weeks based on operating surgeon’s preference and the mean duration of follow-up was 26 months. Conclusion: Robot-assisted laparoscopic VVF repair is convenient and an effective approach in the successful management of VVF in complex fistulas and recurrent cases.

Investigations on coronary artery plaque detection and subclassification using machine learning classifier

Coronary artery diseases are one of the high-risk diseases, which occur due to the insufficient blood supply to the heart. The different types of plaques formed inside the artery leads to the blockage of the blood stream. Understanding the type of plaques along with the detection and classification of plaques supports in reducing the mortality of patients. The objective of this study is to present a novel clustering method of plaque segmentation followed by wavelet transform based feature extraction. The extracted features of all different kinds of calcified and sub calcified plaques are applied to first train and test three machine learning classifiers including support vector machine, random forest and decision tree classifiers. The bootstrap ensemble classifier then decides the best classification result through a voting method of three classifiers. A training dataset including 64 normal CTA images and 73 abnormal CTA images is used, while a testing dataset consists of 111 normal CTA images and 103 abnormal CTA images. The evaluation metrics shows better classification rate and accuracy of 97.7%. The Sensitivity and Specificity rates are 97.8% and 97.5%, respectively. As a result, our study results demonstrate the feasibility and advantages of developing and applying this new image processing and machine learning scheme to assist coronary artery plaque detection and classification.

Arthroplasty Followed by Distraction Osteogenesis Versus Distraction Osteogenesis Followed by Arthroplasty in the Management of TMJ Ankylosis: A Comparative Study

Aim

To compare treatment outcome of arthroplasty followed by distraction osteogenesis (AFD) and distraction osteogenesis followed by arthroplasty (DFA) in the management of mandibular deficiencies in temporomandibular joint (TMJ) ankylosis.

Materials and methods

A total of 20 patients with TMJ Ankylosis were included in the study. Patients were randomly divided into two groups. Group 1 consisted of patients for whom arthroplasty was done prior to distraction osteogenesis (AFD) for the correction of deficient mandible. Group 2 included patients where distraction osteogenesis was performed prior to arthroplasty (DFA). The treatment outcome was assessed based on maximum interincisal distance, overjet, corpus length, ramus height, upper airway, lower airway, duration of the procedure and the complications for the treatment at the end of 3, 6 and 12 months.

Results

After the treatment was ended, the patients of both groups had increase in mouth opening and appearance was improved remarkably. There was general increase in all the parameters in both the groups. But at the end of 12 months, airway and the ramus height were more stable and the control of the proximal segment was superior in DFA group. Open bite was noticed in 2 cases of AFD group which was treated by elastics. There required additional surgery for the removal of distractors in the AFD Group. Establishing the airway during the surgery was easier in AFD group.

Conclusion

The study concludes that distraction followed by arthroplasty was a better procedure for the management of TMJ ankylosis owing to its stable results and less number of surgeries.

Study of anisotropic thermal conductivity in textured thermoelectric alloys by Raman spectroscopy

Polycrystalline p-type Sb_1.5Bi_0.5Te₃ (SBT) and n-type Bi₂Te_2.7Se_0.3 (BTS) compounds possessing layered crystal structure show anisotropic electronic and thermal transport properties. This research is in pursuit of better understanding the anisotropic thermal properties using Raman spectroscopy. A systematic Raman spectroscopic study of the hot-pressed pellet of the textured p-type SBT and n-type BTS is reported in both directions: parallel (‖) and perpendicular (⊥) to the pressing axis as a function of temperature and laser power. The first-order temperature coefficient, optical thermal conductivity, and phonon lifetime are qualitatively determined from the temperature and laser power-dependent frequency and full-width half maximum (FWHM) of Raman peaks (A¹ _1g, E² _g & A² _1g). Anisotropy in experimental phonon thermal conductivity in both directions is correlated with the approximated optical thermal conductivity, phonon lifetime and phonon anharmonicity. The anisotropy in phonon anharmonicity in both directions is explained by the modified Klemens-Hart-Aggarwal-Lax phonon decay model. In this study, the symmetric three-phonon scattering process is considered responsible for thermal transport in the temperature range of 300 to 473 K.