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Background: Lymph node metastasis is a critical prognostic factor for patients with gastric carcinoma (GC). Sentinel lymph node (SLN) mapping has the potential to identify the initial site of draining lymph node metastasis and reduce the extent of surgical lymphadenectomy. This study aimed to evaluate the diagnostic accuracy of SLN mapping in GC. Methods: The study enrolled 129 GC patients undergoing total or partial gastrectomy with D2 lymphadenectomy and indocyanine green fluorescence-guided SLN mapping. The primary outcomes were the negative predictive value (NPV) and sensitivity of SLN mapping. The secondary outcomes were clinicopathologic factors associated with SLN mapping accuracy and successful SLN mapping. Results: The SLN detection rate in this study was 86.8 %. The study had an overall NPV of 83.1 % and an overall sensitivity of 65.8 %. The NPV was found to be significantly higher in the patients with no lymphovascular invasion (LVI) than in those with LVI (96.0 % vs 59.3 %; p < 0.001) and in the patients whose pathologic T (pT) stage lower than 3 than in those whose T stage was 3 or higher (92.0 % vs 66.7 %; p = 0.009). The sensitivity of SLN mapping was 50 % in the patients with no LVI and 33 % in the patients with a pT stage lower than 3. Conclusion: The study results showed that for patients with early-stage GC with no LVI, negative SLN findings may represent a potential additive predictor indicating the absence of regional LN metastasis. However, given the low sensitivity rates noted, further research is needed to identify specific patient populations that may benefit from SLN mapping in GC. [ABSTRACT FROM AUTHOR]

Diverse rice germplasm comprising 112 genotypes was evaluated for yield traits across three environments. Pooled and environmentwise analysis of variance revealed heterogeneity in the data and significant environment interactions for all the yield traits. As per AMMI (additive main effects and multiplicative interaction) and GGE (genotype and genotype x environment interaction) biplots, the influence of environment was significant and varying on all the component yield traits including grain yield and was not significant in case of flowering date. Dry season at Maruteru in 2014–15 (E1) was the most discriminative and representative environment for favourable plant growth in terms of plant height, panicle number and panicle length. None of the environments represented ideal environment for the favourable expression of grain number while all the environments were equally informative for thousand grain weight and grain yield. Panicle number, grain number and thousand grain weight were contributing to grain yield across the environments. Three genotypes Panthdhan 12, Konark and Udaygiri were the most stable genotypes for grain yield with favourable combination of associated yield genes for all the traits, viz. 1000 grain weight, the number of grains per panicle, the number of filled grains per panicle, productive tillers and plant height with higher yield, and grouped in one cluster. Genotyping using previously reported markers revealed that favourable alleles of yield genes associated with the number of productive tillers were predominantly found followed by alleles for the number of grains/filled grains per panicle correlating with the superior phenotypic value of the respective trait. The information on association of yield stability with reported yield genes from this study is useful in marker-assisted breeding studies for yield improvement and can be confirmed with various sets of genotypes under multi-environment testing. The identified superior genotypes are potential components in future breeding programmes and the development of stable adaptable varieties. The present study suggests that yield stability could be effectively achieved with targeted improvement of component yield traits associated with favourable alleles. [ABSTRACT FROM AUTHOR]

The stem rot caused by Sclerotium hydrophilum and false smut caused by Ustilaginoidea virens are two of the major production constraints in rice cultivation in India and other countries. Stem rot and false smut can be effectively controlled with synthetic fungicides. However, the indiscriminate use of chemical fungicides may cause development of resistance among the pathogens. In addition to this, synthetic fungicides also exhibit harmful impacts on the environment. Exploiting microbe-based alternatives for managing plant diseases diminishes public concerns about the ill effects of pesticide usage in crops. In this regard, the present study was designed to investigate the potential of native microbial biocontrol agents (BCAs) from rice rhizosphere for the sustainable management of stem rot and false smut diseases in rice. Potential BCAs and pathogens were identified and characterized through morphological, biochemical, and sanger sequencing techniques. Bio-efficacy tests of potential BCAs against stem rot and false smut diseases on rice under glasshouse conditions indicated higher seed vigour index of the treated seeds, significant improvement in the growth of the seedling, increased dry weight, reduction in percentage disease index viz., 70.03% (stem rot) and 69.24% (false smut) over the control plants. Phytohormones indole acetic acid (IAA), abscisic acid (ABA), gibberellic acid (GA), salicylic acid (SA), and zeatin (tZ) were detected and quantified in the four potential BCAs using liquid chromatography- tandem mass spectrometry (LC–MS/MS). Scanning electron microscopy (SEM) studies revealed the endophytic nature of the strains in rice. The study indicated a positive correlation between the diversity and concentration of phytohormones released by the bioagents and enhanced plant growth promotion and disease suppression in rice. [ABSTRACT FROM AUTHOR]

In this paper, we study Weyl modules for a toroidal Lie algebra T with arbitrary n variables. Using the work of Rao (Pac. J. Math. 171(2), 511–528 1995), we prove that the level one global Weyl modules of T are isomorphic to suitable submodules of a Fock space representation of T up to a twist. As an application, we compute the graded character of the level one local Weyl module of T , thereby generalising the work of Kodera (Lett. Math. Phys. 110(11) 3053–3080 2020). [ABSTRACT FROM AUTHOR]

Gangavati sona (GS) is a high-yielding, fine-grain rice variety widely grown in the Tungabhadra command area in Karnataka, India; however, it is susceptible to bacterial blight (BB). Therefore, the present study was conducted to improve the GS variety for BB resistance. Three BB-resistant genes (xa5, xa13, and Xa21) were introgressed into the genetic background of susceptible cultivar GS through marker-assisted backcrossing (MABB) by using Improved samba Mahsuri (ISM), a popular, high-yielding, bacterial blight resistant rice variety as a donor parent. Foreground selection was carried out using gene-specific markers, viz., xa5FM (xa5), xa13prom (xa13), and pTA248 (Xa21), while background selection was carried out using well-distributed 64 polymorphic microsatellite markers. The true heterozygote F1 was used as the male parent for backcrossing with GS to obtain BC1F1. The process was repeated in BC1F1 generation, and a BC2F1 plant (IGS-5-11-5) possessing all three target genes along with maximum recurrent parent genome (RPG) recovery (86.7%) was selfed to obtain BC2F2s. At BC2F2, a single triple gene homozygote plant (IGS-5-11-5-33) with 92.6% RPG recovery was identified and advanced to BC2F5 by a pedigree method. At BC2F5, the seven best entries were selected, possessing all three resistance genes with high resistance levels against bacterial blight, yield level, and grain quality features equivalent to better than GS. The improved versions of GS will immensely benefit the farmers whose fields are endemic to BB. [ABSTRACT FROM AUTHOR]

Breeding for "weed competitive" cultivars is a prioritized goal under direct seeded rice (DSR) conditions for achieving higher grain yields. Early seedling vigour (ESV) is an imperative trait that imparts weed competitiveness through initial rapid growth and uniform crop establishment. African rice species Oryza glaberrima has been recognised as potential donors for weed competitive traits due to their early vegetative vigour. In the present study, 29 accessions of O. glaberrima were evaluated for early seedling vigour traits under laboratory and DSR conditions. Seedling vigour index-I and II estimated from the paper roll method under laboratory condition revealed that six O. glaberrima accessions (EC861796, EC861801, EC861804, EC861814, EC861819 and EC861820) had higher/similar seedling vigour indices than high vigour check Sabita. In addition, during Kharif 2017 and Rabi 2018, O. glaberrima accessions were phenotyped for nine ESV traits, e.g. seedling height, number of leaves/tillers, leaf area, shoot fresh/dry weight, absolute growth rate, specific leaf area and crop growth rate under DSR condition. Significant genetic variation and genotype × environment interaction was observed for ESV traits under DSR condition. The heritability estimates for ESV traits were ranging from low to high, indicating complex inheritance of the trait. The study identified six accessions of O. glaberrima (EC861787, EC861790, EC861792, EC861795, EC861819 and EC861820) as promising accessions with early seedling vigour based on mean performance in both seasons under direct seeded rice condition. Thus, our study demonstrated inherent nature of early seedling vigour in O. glaberrima and these promising accessions could be exploited for breeding weed-competitive rice cultivars. [ABSTRACT FROM AUTHOR]

For pediatric rehabilitation, obtaining accurate coupled human-exoskeleton system models is challenging due to unknown model parameters caused by children's dynamic growth and development. These factors make it difficult to establish precise and standardized models for exoskeleton control. Additionally, external disturbances, such as unpredictable movements or involuntary muscle contractions, further complicate the control process that must be addressed. This work presents the computed torque control (CTC) scheme compensated by a radial basis function neural network (RBFNN) for an uncertain lower-limb exoskeleton system. Primarily, the design, hardware architecture, and experimental procedure of a pediatric exoskeleton are briefly demonstrated. Thereafter, the proposed adaptive RBFNN-CTC (ARBFNN-CTC) is highlighted, where the adaptation of network weights depends on the Gaussian function and the Lyapunov equation. The adaptive RBFNN estimates the unknown model dynamics and compensates the CTC for the effective gait tracking of the coupled system in passive-assist mode. A Lyapunov stability is presented to ensure the convergence of error states into a significantly small domain. Finally, an experimental study with a pediatric subject (12 years) is carried out to investigate the effectiveness of the proposed control scheme. The gait tracking results show that the ARBFNN-CTC outperforms the traditional CTC by nearly 40 % over three gait cycles. Furthermore, the proposed approach's generalizability is validated across various gait cycles, especially at 3, 10, 20, and 30 cycles. The high correlation coefficients of 0.996, 0.997, and 0.999 for the hip, knee, and ankle joints, respectively, at thirty gait cycles, highlight the potential of the ARBFNN-CTC scheme in achieving effective and consistent gait training outcomes over extended periods. [ABSTRACT FROM AUTHOR]

In an agriculturally dependent country like India, efficient and reliable forecasting techniques for various climatic parameters are essential. Temperature is one of the most significant climatic factors on agriculture and allied industry output. Because of the existence of a spatiotemporal pattern, temperature forecasting is one of the most difficult tasks in this context. For modeling and forecasting spatiotemporal time series data, STARMA (space–time autoregressive moving average) models are widely used. Using a spatial weight matrix, the STARMA model incorporates the spatial effects of neighboring sites into the model. The uniform weightage scheme is the most commonly used weight assigning method in the development of spatial weight matrices. One of the major disadvantages of uniform spatial weight matrices is that they do not account for spatial dynamics and heterogeneity. Hence, there is a need to develop a new weight matrix that is statistically sound and can address the shortcomings of the uniform matrix. In this study, an improved STARMA model based on the weight matrix of a fuzzy inference system (FIS) has been proposed to address the issue. The FIS weights are calculated using the crow distance between the central points of the sites and the time series correlation. Using spatial–temporal temperature series data from seven districts in West Bengal, India, from January 1998 to December 2013, the proposed approach was empirically illustrated. To validate the proposed model, it was used to look at similar space–time temperature data from nine districts in the Indian state of Karnataka from January 2000 to December 2016. For both datasets, the proposed fuzzy rule–based weighted STARMA model was found to be superior to the STARMA as well as the autoregressive integrated moving average (ARIMA) models. The average mean absolute percentage error (MAPE) of the proposed model for all locations considered was 1.78, whereas the average MAPE of the conventional STARMA model and the ARIMA model were 2.09 and 4.39, respectively. This manuscript has not been submitted to, nor is under review at, another journal or other publishing venue. [ABSTRACT FROM AUTHOR]

The present work deals with a system attached to a mass and a Pneumatic Artificial Muscle (PAM) actuator with time-varying pneumatic pressure which results in a direct and parametrically excited system. The governing differential equation of motion is solved using the second-order method of multiple scales (MMS) and the closed-form equations are determined. With the help of these equations, the parametric instability regions have been studied for simple and principal parametric resonance conditions. The influence of different muscle parameters, damping, amplitude and frequency of the time-varying pressures on the instability regions are investigated and verify with the help of time response and phase portraits. This study can be useful for designers and researchers to get an idea about the critical values and safe operating range of different parameters of the PAM. [ABSTRACT FROM AUTHOR]

Graves' ophthalmopathy (GO) is an autoimmune disease of the retroocular tissue occurring in patients with Grave's disease leading to exophthalmos. Exophthalmos is usually detected by inspection using Nafziger's method and objectively measured with Hertel's exophthalmometry. Here we have described a novel technique "Pen touch test" to clinically diagnose exophthalmos. This cross-sectional study was conducted on patients with suspicious hyperthyroid ophthalmopathy/Grave's ophthalmopathy (GO) who underwent eye examination by Nafziger's method and our proposed new method "Pen Touch Test (PTT)". In this test, a clean ruler or pen is held straight over the middle of orbital ridge touching the superior orbital margin and ipsilateral malar eminence. In normal persons, the ruler or pen touches both the superior orbital margin and ipsilateral malar eminence with or without touching eyelids. In patients with GO, there is true bulging forward of the eyeball. Hence, the ruler or pen cannot be made to touch both upper orbital margin and malar eminence simultanously. The presence and degree of exophthalmos was measured objectively on Hertel's exophthalmometry, which was considered the "gold standard". Pen touch test was found to have 100% sensitivity, 100% specificity and 100% Positive Predictive value. Whereas Nafziger's method had a sensitivity of only 75% compared to Hertel's exophthalmometry as gold standard test. "Pen touch test" is simple and sensitive method that can be used to screen for exophthalmos in suspected cases of Grave's ophthalmopathy. [ABSTRACT FROM AUTHOR]

In this paper, an adaptive motion-force control scheme is presented for a networked ultrasound robotic manipulator to perform a transversal abdomen scan. An adaptive backstepping position controller is designed to ensure the stability of the ultrasound robot in the presence of parametric uncertainties and external disturbances. A proportional-integral-derivative force controller is proposed to maintain a constant interaction force during the scan process. Rather than periodic time-triggered implementation, the Lyapunov-based triggering condition is derived to update the control inputs in an aperiodic manner, reduce the communication burden, and preserve the stability of the robotic system during the task. The effectiveness of the proposed control strategy is investigated based on a comparison study with different time-triggered adaptive control schemes. Moreover, the proposed event-triggered mechanism is compared with the most common triggering conditions in literature, i.e., fixed and relative thresholds. These schemes are devoted to carry out the transversal ultrasound scan in the simulation environment. Additional validation of the proposed control scheme is performed in the virtual robot experimentation platform (V-REP). From the results of simulation and experimental runs, the proposed event-triggered control scheme is found to be more promising and efficient in robot-assisted ultrasound imaging. [ABSTRACT FROM AUTHOR]

The basic routine movements for elderly people are not easily accessible due to the weak muscles and impaired nerves in their lower extremity. In the last few years, many robotic-based rehabilitation devices, like orthosis and exoskeletons, have been designed and developed by researchers to provide locomotion assistance to support gait behavior and to perform daily activities for elderly people. However, there is still a need for improvement in the design, actuation and control of these devices for making them cost-effective in the worldwide market. In this work, a systematic review is presented on available lower limb orthosis and exoskeleton devices, to date. The devices are broadly reviewed according to joint types, actuation modes and control strategies. Furthermore, tabular comparisons have also been presented with the types and applications of these devices. Finally, the needful improvements for realizing the efficacy of lower limb rehabilitation devices are discussed along with the development stage. This review will help the designers and researchers to develop an efficient robotic device for the rehabilitation of the lower limb. [ABSTRACT FROM AUTHOR]

The wild species of rice, Oryza rufipogon, is a source of genetic variation for yield-enhancing traits and blast resistance. With the objective to genetically enhance the elite rice cultivar, 'Samba Mahsuri', a set of 192 BC2F2 and BC2F3 lines developed from O. rufipogon was characterized for yield-enhancing traits and blast resistance. The study revealed the presence of significant genetic variability and transgressive segregation for productive tillers, spikelets per panicle, and grain yield per plant. The study also identified several introgression lines superior to the recurrent parent for yield enhancing traits and blast resistance. Molecular characterization of 26 blast resistant lines identified multiple blast resistance genes in IL-136 [Pib, Pi9 (t), Pi54, Pi38, Pitp and Pi20(t)], IL-3 [Pib, Pi54, Pi38, Pitp and Pi20(t)], and IL-140 [Pib, Pi9(t), Pi54, Pi38, and Pitp]. Based on the performance of yield-enhancing traits and blast resistance, seven lines (IL-27, IL-28, IL-29, IL-72, IL-139, IL-158 and IL-171) showed merit. Estimation of the recovery of the recurrent parental genome by using 117 polymorphic SSR markers revealed that recurrent-parental genome recovery varied from 54.0 (IL-158) to 92.3% (IL-27). These promising, high-yielding introgression lines with multiple blast-resistance genes can serve as important genetic resources for yield and blast resistance improvement in rice, especially for the southern India. [ABSTRACT FROM AUTHOR]

Corticosteroids, anti-CD20 agents, immunotherapies, and cytotoxic chemotherapy are commonly used in the treatment of patients with cancer. It is unclear how these agents affect patients with cancer who are infected with SARS-CoV-2. We retrospectively investigated associations between SARS-CoV-2-associated respiratory failure or death with receipt of the aforementioned medications and with pre-COVID-19 neutropenia. The study included all cancer patients diagnosed with SARS-CoV-2 at Memorial Sloan Kettering Cancer Center until June 2, 2020 (N = 820). We controlled for cancer-related characteristics known to predispose to worse COVID-19 as well as level of respiratory support during corticosteroid administration. Corticosteroid administration was associated with worse outcomes prior to use of supplemental oxygen; no statistically significant difference was observed in sicker cohorts. In patients with metastatic thoracic cancer, 9 of 25 (36%) and 10 of 31 (32%) had respiratory failure or death among those who did and did not receive immunotherapy, respectively. Seven of 23 (30%) and 52 of 187 (28%) patients with hematologic cancer had respiratory failure or death among those who did and did not receive anti-CD20 therapy, respectively. Chemotherapy itself was not associated with worse outcomes, but pre-COVID-19 neutropenia was associated with worse COVID-19 course. Relative prevalence of chemotherapy-associated neutropenia in previous studies may account for different conclusions regarding the risks of chemotherapy in patients with COVID-19. In the absence of prospective studies and evidence-based guidelines, our data may aid providers looking to assess the risks and benefits of these agents in caring for cancer patients in the COVID-19 era. [ABSTRACT FROM AUTHOR]

To improve grain yield under direct seeded and aerobic conditions, weed competitive ability of a rice genotype is a key desirable trait. Hence, understanding and dissecting weed competitive associated traits at both morphological and molecular level is important in developing weed competitive varieties. In the present investigation, the QTLs associated with weed competitive traits were identified in BC1F2:3 population derived from weed competitive accession of O. glaberrima (IRGC105187) and O. sativa cultivar IR64. The mapping population consisting of 144 segregating lines were phenotyped for 33 weed competitive associated traits under direct seeded condition. Genetic analysis of weed competitive traits carried out in BC1F2:3 population showed significant variation for the weed competitive traits and predominance of additive gene action. The population was genotyped with 81 genome wide SSR markers and a linkage map covering 1423 cM was constructed. Composite interval mapping analysis identified 72 QTLs linked to 33 weed competitive traits which were spread on the 11 chromosomes. Among 72 QTLs, 59 were found to be major QTLs (> 10% PVE). Of the 59 major QTLs, 38 had favourable allele contributed from the O. glaberrima parent. We also observed nine QTL hotspots for weed competitive traits (qWCA2a, qWCA2b, qWCA2c, qWCA3, qWCA5, qWCA7, qWCA8, qWCA9, and qWCA10) wherein several QTLs co-localised. Our study demonstrates O. glaberrima species as potential source for improvement for weed competitive traits in rice and identified QTLs hotspots associated with weed competitive traits. [ABSTRACT FROM AUTHOR]

Efficient and reliable forecasting techniques for various climatic conditions are indispensable in agricultural dependent country like India. In this context, rainfall forecasting is one of the most challenging tasks because of the existence of three patterns, viz., temporal, spatial, and non-linear, simultaneously. Space-Time Autoregressive Moving Average (STARMA) model is one of the promising and popular approaches for modelling spatio-temporal time series data. However, the observed features of many space-time rainfall data comprise complex non-linear dynamics and modelling these patterns often go beyond the capability of conventional STARMA model. Moreover, despite the popularity of artificial neural network (ANN) and support vector machine (SVM) for modelling complex non-linear dynamics, they are not capable to deal with spatial patterns. To overcome the problem, a new spatio-temporal hybrid modelling approach has been proposed by integrating STARMA, ANN, and SVM as well. The proposed approach has been empirically illustrated on annual precipitation data of six districts of northern part of West Bengal, India. The study reveals that proposed spatio-temporal hybrid approach has better modelling and forecasting precision over conventional STARMA as well as most widely used Autoregressive Integrated Moving Average (ARIMA) model. [ABSTRACT FROM AUTHOR]

In this work, theoretical and experimental analysis of a piezoelectric energy harvester with parametric base excitation is presented under combination parametric resonance condition. The harvester consists of a cantilever beam with a piezoelectric patch and an attached mass, which is positioned in such a way that the system exhibits 1:3 internal resonance. The generalized Galerkin's method up to two modes is used to obtain the temporal form of the nonlinear electromechanical governing equation of motion. The method of multiple scales is used to reduce the equations of motion into a set of first-order differential equations. The fixed-point response and the stability of the system under combination parametric resonance are studied. The multi-branched non-trivial response exhibits bifurcations such as turning point and Hopf bifurcations. Experiments are performed under various resonance conditions. This study on the parametric excitation along with combination and internal resonances will help to harvest energy for a wider frequency range from ambient vibrations. [ABSTRACT FROM AUTHOR]

Snake robots are used for surveillance in unknown underwater environments. The robot comes across the drag force and added mass effect during the motion. The speed of the robot is very low in the underwater environment. Therefore, some thrust force is required to increase the speed. In this work, the snake robot follows a path in uncertain environments with external disturbances. The speed of the snake robot is improved by implementing a thruster at the tail of a snake robot. The equation of motion for the snake robot is derived by considering the effect of the thrust force on each link. The virtual holonomic constraints are formulated to derive the reduced-order dynamical system. The control objective is defined based on reduced-order dynamics using the sliding surface approach. The super-twisting sliding mode control (STSMC) scheme with reinforcement learning (i.e. actor-critic neural network) is proposed for the motion control of the snake robot in the uncertain underwater environment. The dynamic model of the snake robot (equivalent control law) is estimated using the reinforcement learning control approach. The switching control law is designed using the STSMC. The proposed control scheme not only improves the tracking errors but also reduces the chattering effect and control effort. Finally, these results are verified by comparing them to the existing control scheme. Overall, the online dynamic model estimation problem is addressed by designing the controller for the head link of the snake robot. [ABSTRACT FROM AUTHOR]

The objectives of this study were to ascertain the feasibility of transcanal endoscopic underlay myringoplasty using temporalis fascia and compare the results with microscopic myringoplasty. This prospective randomized trial included 60 patients with mucosal chronic otitis media with tympanic membrane perforations of all sizes and locations apart from posteriorly based small or moderate sized perforations. In the endoscopy group, 30 patients underwent exclusive transcanal myringoplasty using tympanomeatal flap elevation with underlay graft placement. In the microscopy group, 30 patients underwent myringoplasty using the postaural approach. Intra-operative variables compared were canalplasty and canal wall curettage for assessment of ossicular status. Graft uptake, hearing outcomes using pure tone audiometry and subjective cosmetic outcomes were assessed 24 weeks post-operatively and compared in the two groups. Resident feedback on the feasibility of endoscopic myringoplasty was obtained using a questionnaire. In the microscopy group, 5/30 patients required canalplasty due to canal overhangs and 4/30 required canal wall curettage for ossicular assessment, whereas none of the patients in the endoscopy group required these procedures. A graft uptake rate of 83.3 % was observed in both groups post-operatively after 24 weeks. Mean air-bone gap pre- and post-operatively in the endoscopy group was 28.5 and 18.13 dB, respectively, whereas these values were 32.4 and 16.9 dB, respectively, in the microscopy group. Subjective cosmetic outcomes were better in the endoscopy group. Resident feedback on endoscopic myringoplasty was positive. Endoscopic myringoplasty appears to be an effective alternative to microscopic myringoplasty and results in excellent hearing with good cosmetic outcomes. [ABSTRACT FROM AUTHOR]

In this work, the stability of a flexible thin cylindrical workpiece in turning is analyzed. A process model is derived based on a finite element representation of the workpiece flexibility and a nonlinear cutting force law. Repeated cutting of the same surface due to overlapping cuts is modeled with the help of a time delay. The stability of the so obtained system of periodic delay differential equations is then determined using an approximation as a time-discrete system and Floquet theory. The time-discrete system is obtained using the semi-discretization method. The method is implemented to analyze the stability of two different workpiece models of different thicknesses for different tool positions with respect to the jaw end. It is shown that the stability chart depends on the tool position as well as on the thickness. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Traditional ionic polymer metal composites (IPMCs) composed of Nafion as the base polymer and mostly precious metal platinum/gold as the surface electrode. The proposed work deal with fabrication and investigation of thermo-electromechanical properties of artificial muscles i.e. ionic polymer-metal composites of non-precious metal silver (Ag) as surface electrode. Chemical decomposition method is followed and in-depth fabrication procedures are outlined. The microscopic and morphological analyses show dense packed silver (Ag) particles on the surface of the Nafion membrane. Several experiments are carried out such as bending test for measuring tip force and surface resistance. Dynamic-mechanical analysis (DMA) and thermo-mechanical analysis (TMA) are performed to evaluate the viscoelastic properties and performance of the actuator. The developed pure Ag-IPMC is inexpensive, exhibits superior performance and can be used as artificial muscle materials. [ABSTRACT FROM AUTHOR]

In the present work, the nonlinear response of a vertically moving viscoelastic beam subjected to a periodically varying contact load is investigated. The generalized Galerkin's method is used to discretize the nonlinear partial differential equation of motion into the temporal equation of motion. The temporal equation of motion contains many nonlinear terms such as cubic geometric and inertial nonlinear terms, nonlinear damping term, and nonlinear parametric excitation terms in addition to forced excitation and parametric excitation terms. The first-order approximate solutions are obtained by using the method of multiple scales, and the stability and bifurcations of the obtained steady-state responses are studied. Extensive numerical simulations are presented to illustrate the influences of various types of system parameters for different resonance conditions. A significant amount of vibration reduction is obtained with the increase in the material loss factor. The results obtained by numerically solving the temporal equation of motion are found to be in good agreement with the results determined by the method of multiple scales. The obtained results are useful for reduction in the vibration of the viscoelastic flexible beam with prismatic joint or single-link viscoelastic Cartesian manipulator with payload subjected to a sinusoidally varying contact load. [ABSTRACT FROM AUTHOR]

Abstract  In this present work, the nonlinear response of a single-link flexible Cartesian manipulator with payload subjected to a pulsating axial load is determined. The nonlinear temporal equation of motion is derived using D’Alembert’s principle and generalised Galerkin’s method. Due to large transverse deflection of the manipulator, the equation of motion contains cubic geometric and inertial types of nonlinearities along with linear and nonlinear parametric and forced excitation terms. Method of normal forms is used to determine the approximate solution and to study the dynamic stability and bifurcations of the system. These results are found to be in good agreement with those obtained by numerically solving the temporal equation of motion. Influences of amplitude of the base excitation, mass ratio, and amplitude of static and dynamic axial load on the steady state responses of the system are investigated for three different resonance conditions. For some specific conditions, the results obtained in this work are found to be in good agreement with the previously published experimental work. The results obtained in this work will find applications in the design of flexible Cartesian manipulators with payload. [ABSTRACT FROM AUTHOR]

In the present investigation, AA 5083 foam structures were fabricated, and the quasi-static uniaxial loading behavior of AA 5083 foam with varying concentration of blowing agent (CaCO3) was studied. Also, the effect of the CaCO3 blowing agent on the foam features such as pore size, pore circularity, pore distribution, and cell wall thickness was also carried out. It was observed that with the increase in CaCO3 (wt%), the relative density of the foam and the plateau stress, and the energy absorption of the foam get reduced. The influence of blowing agent on the pore features such as pore size and distribution seemed to be minimal; therefore, no significant improvement in the pore circularity was found. The quasi-static compression test results have got affected due to the varying plastic strength of the foam that resulted due to changes in the pore size and circularity. However, a detailed analysis of the dependence of these AA 5083 foam features (porosity, pore size distribution, and circularity) on CaCO3 blowing agent is discussed in this article. [ABSTRACT FROM AUTHOR]

Understanding plant traits is essential for decoding the behavior of various genomes and their reactions to environmental factors, paving the way for efficient and sustainable agricultural practices. Image-based plant phenotyping has become increasingly popular in modern agricultural research, effectively analyzing large-scale plant data. This study introduces a new high-throughput plant phenotyping system designed to examine plant growth patterns using segmentation analysis. This system consists of two main components: (i) A plant detector module that identifies individual plants within a high-throughput imaging setup, utilizing the Tiny-YOLOv4 (You Only Look Once) architecture. (ii) A segmentation module that accurately outlines the identified plants using the Chan-Vese segmentation algorithm. We tested our approach using top-view RGB tray images of the ‘Arabidopsis Thaliana’ plant species. The plant detector module achieved an impressive localization accuracy of 96.4% and an average Intersection over Union (IoU) of 77.42%. Additionally, the segmentation module demonstrated strong performance with dice and Jaccard scores of 0.95 and 0.91, respectively. These results highlight the system’s capability to define plant boundaries accurately. Our findings affirm the effectiveness of our high-throughput plant phenotyping system and underscore the importance of employing advanced computer vision techniques for precise plant trait analysis. These technological advancements promise to boost agricultural productivity, advance genetic research, and promote environmental sustainability in plant biology and agriculture. [ABSTRACT FROM AUTHOR]

Most rapidly proliferating mammalian cells rely on the oxidation of exogenous glutamine to support cell proliferation. We previously found that culture of mouse embryonic stem cells (ESCs) in the presence of inhibitors against MEK and GSK3β to maintain pluripotency reduces cellular reliance on glutamine for tricarboxylic acid (TCA) cycle anaplerosis, enabling ESCs to proliferate in the absence of exogenous glutamine. Here we show that reduced dependence on exogenous glutamine is a generalizable feature of pluripotent stem cells. Enhancing self-renewal, through either overexpression of pluripotency-associated transcription factors or altered signal transduction, decreases the utilization of glutamine-derived carbons in the TCA cycle. As a result, cells with the highest potential for self-renewal can be enriched by transient culture in glutamine-deficient media. During pluripotent cell culture or reprogramming to pluripotency, transient glutamine withdrawal selectively leads to the elimination of non-pluripotent cells. These data reveal that reduced dependence on glutamine anaplerosis is an inherent feature of self-renewing pluripotent stem cells and reveal a simple, non-invasive mechanism to select for mouse and human pluripotent stem cells within a heterogeneous population during both ESC passage and induced pluripotent cell reprogramming.