Forecasting global plastic production and microplastic emission using advanced optimised discrete grey model

Plastic pollution has become a prominent and pressing environmental concern within the realm of pollution. In recent times, microplastics have entered our ecosystem, especially in freshwater. In the contemporary global landscape, there exists a mounting apprehension surrounding the manifold environmental and public health issues that have emerged as a result of the substantial accumulation of microplastics. The objective of the current study is to employ an enhanced grey prediction model in order to forecast global plastic production and microplastic emissions. This study compared the accuracy level of the four grey prediction models, namely, EGM (1,1, α, θ), DGM (1,1), EGM (1,1), and DGM (1,1, α) models, to evaluate the accuracy levels. As per the estimation of the study, DGM (1,1, α) was found to be more suitable with higher accuracy levels to predict microplastic emission. The EGM (1,1, α, θ) model has slightly better accuracy than the DGM (1,1, α) model in predicting global plastic production. Various accuracy measurement tools (MAPE and RMSE) were used to determine the model's efficiency. There has been a gradual growth in both plastic production and microplastic emission. The current study using the DGM (1,1, α) model predicted that microplastic emission would be 1,084,018 by 2030. The present study aims to provide valuable insights for policymakers in formulating effective strategies to address the complex issues arising from the release of microplastics into the environment and the continuous production of plastic materials.

Efficacy of different respiratory supports to prevent hypoxia during flexible bronchoscopy in patients of COPD: a triple-arm, randomised controlled trial

BACKGROUND

Patients with chronic-obstructive-pulmonary-disease (COPD) undergo bronchoscopy for various reasons, and are at relatively higher risk of complications. This study evaluated the efficacy of non-invasive ventilation (NIV) and high-flow-oxygen-therapy (HFOT) compared with conventional-oxygen-therapy (COT) in patients with COPD undergoing bronchoscopy, to prevent hypoxia.

METHODS

It was a triple-arm, open-label, randomised controlled trial. Ninety patients with COPD were randomly assigned into three intervention arms in 1:1:1 ratio. The incidence of hypoxia, lowest recorded oxygen saturation measured by plethysmography (SpO2), ECG, patient vitals and comfort levels were assessed.

RESULTS

Mean age of the study population was 61.71±7.5 years. Out of 90 cases enrolled, 51, 34 and 5 were moderate, severe and very-severe COPD, respectively, as per GOLD (Global Initiative for Chronic Obstructive Lung Disease) classification. Rest of the baseline characteristics were similar. SpO2 during flexible bronchoscopy (FB) was lowest in COT group (COT: 87.03±5.7% vs HFOT: 95.57±5.0% vs NIV: 97.40±1.6%, p<0.001). Secondary objectives were similar except respiratory-rate (breaths-per-minute) which was highest in COT group (COT: 20.23±3.1 vs HFOT: 18.57±4.1 vs NIV: 16.80±1.9, p<0.001). Whereas post FB partial of oxygen in arterial blood was highest in NIV group (NIV: 84.27±21.6 mm Hg vs HFOT: 69.03±13.6 mm Hg vs COT: 69.30±11.9 mm Hg, p<0.001). Post FB partial pressure of carbon dioxide in arterial blood was similar in the three arms. Operator's ease-of-performing-procedure was least in the NIV group as assessed with Visual Analogue Scale (p<0.01). A higher number of NIV group participants reported nasal pain as compared with the other two arms (p<0.01).

CONCLUSION

NIV and HFOT are superior to COT in preventing hypoxia during bronchoscopy, but NIV is associated with poor patient-tolerance and inferior operator's ease of doing procedure.

TRIAL REGISTRATION NUMBER

CTRI/2021/03/032190.

Dissecting genomic regions and underlying sheath blight resistance traits in rice (Oryza sativa L.) using a genome-wide association study

The productivity of rice is greatly affected by the infection of the plant pathogenic fungus Rhizoctonia solani, which causes a significant grain yield reduction globally. There exist a limited number of rice accessions that are available to develop sheath blight resistance (ShB). Our objective was to identify a good source of the ShB resistance, understand the heritability, and trait interactions, and identify the genomic regions for ShB resistance traits by genome-wide association studies (GWAS). In the present study, a set of 330 traditional landraces and improved rice varieties were evaluated for ShB resistance and created a core panel of 192 accessions used in the GWAS. This panel provides a more considerable amount of genetic variance and found a significant phenotypic variation among the panel of rice accessions for all the agro-morphological and disease-resistance traits over the seasons. The infection rate of ShB and disease reaction were calculated as percent disease index (PDI) and area under the disease progress curve (AUDPC). The correlation analysis showed a significant positive association between PDIs and AUPDC and a negative association between PDI and plant height, flag leaf length, and grain yield. The panel was genotyped with 133 SSR microsatellite markers, resulting in a genome coverage of 314.83 Mb, and the average distance between markers is 2.53 Mb. By employing GLM and MLM (Q + K) models, 30 marker-trait associations (MTAs) were identified with targeted traits over the seasons. Among these QTLs, eight were found to be novel and located on 2, 4, 8, 10, and 12 chromosomes, which explained the phenotypic variation ranging from 5% to 15%. With the GWAS approach, six candidate genes were identified. Os05t0566400, Os08t0155900, and Os09t0567300 were found to be associated with defense mechanisms against ShB. These findings provided insights into the novel donors of IC283139, IC 277248, Sivappuchithirai Kar, and Bowalia. The promising genomic regions on 10 of 12 chromosomes associated with ShB would be useful in developing rice varieties with durable disease resistance.

NK, Pavani S. L, Ganesan S, Singh PK, Sah RP, V. P, Subudhi H, Mahender A, Anandan A, Ali J. Multi-environment evaluation of rice genotypes: impact of weather and culm biochemical parameters against sheath blight infection

Introduction

Sheath blight caused by Rhizoctonia solani is one of the major diseases of rice, causing widespread crop losses. The use of semi-dwarf rice varieties in the ongoing nutrient-intensive rice cultivation system has further accentuated the incidence of the disease. An ideal solution to this problem would be identifying a stable sheath blight-tolerant genotype.

Material and methods

A multi-environment evaluation of 32 rice genotypes against sheath blight infection was conducted over six seasons across two locations (Agricultural Research Farm, Institute of Agricultural Sciences, Banaras Hindu University (28.18° N, 38.03° E, and 75.5 masl), for four years during the wet seasons (kharif) from 2015 to 2018 and two seasons at the National Rice Research Institute (20°27'09" N, 85°55'57" E, 26 masl), Cuttack, Odisha, during the dry season (rabi) of 2019 and the kharif of 2019, including susceptible and resistant check. Percent disease index data were collected over 4 weeks (on the 7th, 14th, 21st, and 28th day after infection), along with data on other morphological and physiological traits.

Result and discussion

The resistant genotypes across seasons were the ones with a higher hemicellulose content (13.93-14.64) and lower nitrogen content (1.10- 1.31) compared with the susceptible check Tapaswini (G32) (hemicellulose 12.96, nitrogen 1.38), which might explain the resistant reaction. Three different stability models-additive main effect and multiplicative interaction (AMMI), genotype + genotype x environment (GGE) biplot, and multi-trait stability index (MTSI)-were then used to identify the stable resistant genotypes across six seasons. The results obtained with all three models had common genotypes highlighted as stable and having a low area under the disease progress curve (AUDPC) values. The ideal stable genotypes with low disease incidence were IC 283139 (G19), Tetep (G28), IC 260917 (G4), and IC 277274 (G10), with AUDPC values of 658.91, 607.46, 479.69, and 547.94, respectively. Weather parameters such as temperature, rainfall, sunshine hours, and relative humidity were also noted daily. Relative humidity was positively correlated with the percent disease index.

Assessment of Indian wheat germplasm for Septoria nodorum blotch and tan spot reveals new QTLs conferring resistance along with recessive alleles of Tsn1 and Snn3

The leaf blight diseases, Septoria nodorum blotch (SNB), and tan spot (TS) are emerging due to changing climatic conditions in the northern parts of India. We screened 296 bread wheat cultivars released in India over the past 20 years for seedling resistance against SNB (three experiments) and TS (two experiments). According to a genome-wide association study, six QTLs on chromosome arms 1BL, 2AS, 5BL, and 6BL were particularly significant for SNB across all three years, of which Q.CIM.snb.1BL, Q.CIM.snb.2AS1, Q.CIM.snb.2AS.2, and Q.CIM.snb.6BL appeared novel. In contrast, those on 5BS and 5BL may correspond to Snn3 and Tsn1, respectively. The allelic combination of tsn1/snn3 conferred resistance to SNB, whereas that of Tsn1/Snn3 conferred high susceptibility. As for TS, Tsn1 was the only stably significant locus identified in this panel. Several varieties like PBW 771, DBW 277, and HD 3319, were identified as highly resistant to both diseases that can be used in future wheat improvement programs as resistant donors.

Custodial Death

The authors report a case of death of 16 years old boy in custody of a rehabilitation center. The young boy was taken to hospital for some health issues after severe torture where he was declared dead and brought for medicolegal autopsy under the requisition of investigating authority. Autopsy examination revealed multiple abrasions and intradermal contusions of ante-mortem origin and fresh at the time of death on various parts of the body including intradermal contusions on bilateral soles, subscalpal hematoma, subdural with minimal subarachnoid haemorrhages were observed. Histo-pathological examination of bilateral kidneys revealed features of acute tubular necrosis which is due to release of myoglobin as result of skeletal muscle necrosis sustained due to repeated blunt force trauma. The cause of death was attributed to head injury. Deceased was tortured by hitting over soles which is also known as falanga, and the second most common form of torture after beating the body. The fatal maltreatment and death of people who are detained against their will often raises controversy therefore nonpartisan information on cause of death is required to conclude that human rights were abused. So, medicolegal autopsy provides scientific basis for the occurrence of injury and establishing cause of death.

Heterologous expression and characterization of ToxA1 haplotype from India and its interaction with Tsn1 for spot blotch susceptibility in spring wheat

BACKGROUND

ToxA, a necrotrophic effector protein, is present in the genome of fungal species like Parastagnospora nodorum, Pyrenophora tritici-repentis and Bipolaris sorokiniana. Tsn1 is the sensitivity gene in the host whose presence indicates more susceptibility to ToxA carrying pathogen, and ToxA-Tsn1 interaction follows an inverse gene-for-gene relationship.

METHODS AND RESULTS

The present study involved cloning and expressing the ToxA1 haplotype from B. sorokiniana. It was found that the amplicon exhibited an expected product size of 471 bp. Sequence analysis of the ToxA1 nucleotide sequence revealed the highest identity, 99.79%, with P. tritici-repentis. The protein expression analysis showed peak expression at 16.5 kDa. Phylogenetic analysis of the ToxA1 sequence from all the Bipolaris isolates formed an independent clade along with P. tritici-repentis and diverged from P. nodorum. ToxA-Tsn1 interaction was studied in 18 wheat genotypes (11 Tsn1 and 7 tsn1) at both seedling and adult stages, validating the inverse gene-for-gene relationship, as the toxin activity was highest in the K68 genotype (Tsn1) and lowest in WAMI280 (tsn1).

CONCLUSION

The study indicates that the haplotype ToxA1 is prevailing in the Indian population of B. sorokiniana. It would be desirable for wheat breeders to select genotypes with tsn1 locus for making wheat resistant to spot blotch.

Feasibility and outcomes of Desarda vs Lichtenstein hernioplasty by local anesthesia for inguinal hernia: a noninferiority randomized clinical trial

INTRODUCTION

The Desarda autologous tissue repair is comparable to the Lichtenstein hernioplasty for inguinal hernia regarding recurrence, chronic groin pain, and return to work activities. This study was designed to establish the outcomes of Desarda's repair versus Lichtenstein's hernioplasty concerning post-operative recovery to normal gait and its feasibility under local anesthesia (LA).

MATERIALS AND METHODS

This study was a single-center, prospective, double-blinded, non-inferiority, randomized trial. Patients undergoing open hernia repair for primary inguinal hernia were included. Patients were randomly assigned and followed up for 2 years. The primary endpoint was the time to return to normal gait post-surgery with comfort (non-inferiority margin fixed as 0.5 days). The secondary outcomes studied were post-operative pain score, the time required to return to work (all previously performed activities), and surgical-site occurrences (SSO).

RESULTS

One hundred ten eligible patients were randomly assigned [56 patients (50.9%) in the Desarda group and 54 patients (49.1%) in the Lichtenstein group]. All the procedures were safely performed under LA. The median (interquartile range) time for resuming gait post-surgery with comfort was 5 days in the Desarda vs 4 days in Lichtenstein's arm (P = 0.16), thereby failing to demonstrate non-inferiority of Desarda against Lichtenstein hernioplasty. However, there were no significant differences in days to return to work, SSO, chronic groin pain, and recurrence within two years of surgery.

CONCLUSIONS AND RELEVANCE

This study could not demonstrate the non-inferiority of the Desarda repair versus Lichtenstein hernioplasty regarding the time taken to return to normal gait. Comparing the days to return to work, pain score, SSO, and chronic groin pain, including recurrence rate, Desarda repair faired equally with Lichtenstein hernioplasty, thereby highlighting its feasibility and efficacy under LA.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03512366.

Exergo-enviro-economic and yearly productivity analyses of conical passive solar still for sustainable solar distillation

This paper focuses on exergo-enviro-economic and yearly productivity analyses for conical passive solar still having the potential to fulfil the sustainable development goal of the United Nations. A new approach for thermal modelling of conical passive solar still has been carried out with experimental validation in the present work, wherein different weather conditions have been considered for the analysis of the proposed system. The carried out work has been done for each month of the year. In further methodology, the computational code in MATLAB has been used for the computation of hourly freshwater production, exergy, and energy followed by the estimation of their annual values. Thereafter, exergo-enviro-economic parameters, yearly productivity, payback period, and freshwater cost have been estimated, and the obtained results have been compared with the earlier published research. Concludingly, the exergo-economic parameter, enviro-economic parameter, and yearly productivity for the proposed system have been found higher by 44.25%, 25.68%, and 44.07%, respectively, than the conventional solar still. The comparative freshwater cost is 13.56% less than the conventional solar still for 0.025 m water depth. Additionally, the payback period for the proposed system will remain at 2.75 years, which is 13.82% less in comparison to the conventional solar still considering a 2% interest rate.

Role of Janus Kinase inhibitors in the management of pulmonary involvement due to Long COVID-19 disease: A case control study

OBJECTIVES

Ongoing symptomatic coronavirus disease 2019 (OSC) is defined as persistent symptoms beyond 4 weeks of acute illness. OSC leads to prolonged hospitalization and oxygen dependence. We aimed to find the outcome of Janus kinase inhibitors (JAKi) as a steroid-sparing agent to treat OSC.

METHODS

In this single-center case-controlled study comparing JAKi and corticosteroids in OSC cases, data of 41 cases out of 86 were included - 21 in the JAKi group and 20 in the corticosteroid group from 4 weeks of acute illness to the next 4 weeks. Clinical parameters and inflammatory markers were recorded. The primary outcome was to compare the proportion of patients who were able to maintain oxygen saturation ≥95% with any oxygen supplementation in the two groups.

RESULTS

The baseline clinical and demographic characteristics were similar in the two groups. The age was 53.65 ± 9.8 years and 51.48 ± 14.0 years in the corticosteroid group and JAKi group, respectively. At the baseline, 85% of patients in the corticosteroid group and 85.8% in the JAKi group were on oxygen support. The most common symptom in both groups was breathlessness followed by cough. Twenty percent of patients in the JAKi group received baricitinib and the remaining were given tofacitinib. At the time of follow-up, the majority of cases had a significant reduction in C-reactive protein (CRP) and D-dimer; however, the change in CRP and D-dimer was similar in both groups. The number of patients off oxygen support at 4 weeks was higher in the JAKi group (85% in the corticosteroid group vs. 95.2% in the JAKi group, P = 0.269), and the median time to liberation from oxygen support was significantly lower in JAKi group (19 days in corticosteroid group vs. 9 days in JAKi group, P < 0.001). The frequency of any adverse event was also higher in the corticosteroid group (70% vs. 23.8%, P = 0.003).

CONCLUSION

JAKi can be used as immunomodulatory drugs in hypoxic OSC cases having evidence of ongoing inflammation.

Correction: Genomic surveillance uncovers a pandemic clonal lineage of the wheat blast fungus

[This corrects the article DOI: 10.1371/journal.pbio.3002052.].

Genomic Prediction of Resistance to Tan Spot, Spot Blotch and Septoria Nodorum Blotch in Synthetic Hexaploid Wheat

Genomic prediction combines molecular and phenotypic data in a training population to predict the breeding values of individuals that have only been genotyped. The use of genomic information in breeding programs helps to increase the frequency of favorable alleles in the populations of interest. This study evaluated the performance of BLUP (Best Linear Unbiased Prediction) in predicting resistance to tan spot, spot blotch and Septoria nodorum blotch in synthetic hexaploid wheat. BLUP was implemented in single-trait and multi-trait models with three variations: (1) the pedigree relationship matrix (A-BLUP), (2) the genomic relationship matrix (G-BLUP), and (3) a combination of the two matrices (A+G BLUP). In all three diseases, the A-BLUP model had a lower performance, and the G-BLUP and A+G BLUP were statistically similar (p ≥ 0.05). The prediction accuracy with the single trait was statistically similar (p ≥ 0.05) to the multi-trait accuracy, possibly due to the low correlation of severity between the diseases.

SnapEnsemFS: a snapshot ensembling-based deep feature selection model for colorectal cancer histological analysis

Colorectal cancer is the third most common type of cancer diagnosed annually, and the second leading cause of death due to cancer. Early diagnosis of this ailment is vital for preventing the tumours to spread and plan treatment to possibly eradicate the disease. However, population-wide screening is stunted by the requirement of medical professionals to analyse histological slides manually. Thus, an automated computer-aided detection (CAD) framework based on deep learning is proposed in this research that uses histological slide images for predictions. Ensemble learning is a popular strategy for fusing the salient properties of several models to make the final predictions. However, such frameworks are computationally costly since it requires the training of multiple base learners. Instead, in this study, we adopt a snapshot ensemble method, wherein, instead of the traditional method of fusing decision scores from the snapshots of a Convolutional Neural Network (CNN) model, we extract deep features from the penultimate layer of the CNN model. Since the deep features are extracted from the same CNN model but for different learning environments, there may be redundancy in the feature set. To alleviate this, the features are fed into Particle Swarm Optimization, a popular meta-heuristic, for dimensionality reduction of the feature space and better classification. Upon evaluation on a publicly available colorectal cancer histology dataset using a five-fold cross-validation scheme, the proposed method obtains a highest accuracy of 97.60% and F1-Score of 97.61%, outperforming existing state-of-the-art methods on the same dataset. Further, qualitative investigation of class activation maps provide visual explainability to medical practitioners, as well as justifies the use of the CAD framework in screening of colorectal histology. Our source codes are publicly accessible at: https://github.com/soumitri2001/SnapEnsemFS .

Utility and timing of the respiratory rate-oxygenation index in the prediction of high-flow oxygen therapy failure in acute hypoxemic respiratory failure of infective etiology: a prospective observational study

During and following the COVID-19 pandemic, the world has witnessed a surge in high-flow oxygen therapy (HFOT) use. The ability to provide high oxygenation levels with remarkable comfort levels has been the grounds for the same. Despite the advantages, delays in intubation leading to poor overall outcomes have been noticed in subgroups of patients on HFOT. The respiratory rate-oxygenation (ROX) index has been proposed to be a useful indicator to predict HFOT success. In this study, we have examined the utility of the ROX index prospectively in cases of acute hypoxemic respiratory failure (AHRF) due to infective etiologies. A total of 70 participants were screened, and 55 were recruited for the study. The majority of participants were males (56.4%), with diabetes mellitus being the most common comorbidity (29.1%). The mean age of the study subjects was 46.27±15.6 years. COVID-19 (70.9%) was the most common etiology for AHRF, followed by scrub typhus (21.8%). 19 (34.5%) experienced HFOT failure, and 9 (16.4%) subjects died during the study period. Demographic characteristics did not differ between either of the two groups (HFOT success versus failure and survived group versus expired group). The ROX index was significantly different between the HFOT success versus failure group at baseline, 2, 4, 6, 12, and 24 hours. The best cut-offs of the ROX index at baseline and 2 hours were 4.4 (sensitivity 91.7%, specificity 86.7%) and 4.3 (sensitivity 94.4% and specificity 86.7%), respectively. The ROX index was found to be an efficient tool in predicting HFOT failure in cases of AHRF with infective etiology.

Genomic surveillance uncovers a pandemic clonal lineage of the wheat blast fungus

Wheat, one of the most important food crops, is threatened by a blast disease pandemic. Here, we show that a clonal lineage of the wheat blast fungus recently spread to Asia and Africa following two independent introductions from South America. Through a combination of genome analyses and laboratory experiments, we show that the decade-old blast pandemic lineage can be controlled by the Rmg8 disease resistance gene and is sensitive to strobilurin fungicides. However, we also highlight the potential of the pandemic clone to evolve fungicide-insensitive variants and sexually recombine with African lineages. This underscores the urgent need for genomic surveillance to track and mitigate the spread of wheat blast outside of South America and to guide preemptive wheat breeding for blast resistance.

Genomic surveillance uncovers a pandemic clonal lineage of the wheat blast fungus

Wheat, one of the most important food crops, is threatened by a blast disease pandemic. Here, we show that a clonal lineage of the wheat blast fungus recently spread to Asia and Africa following two independent introductions from South America. Through a combination of genome analyses and laboratory experiments, we show that the decade-old blast pandemic lineage can be controlled by the Rmg8 disease resistance gene and is sensitive to strobilurin fungicides. However, we also highlight the potential of the pandemic clone to evolve fungicide-insensitive variants and sexually recombine with African lineages. This underscores the urgent need for genomic surveillance to track and mitigate the spread of wheat blast outside of South America and to guide preemptive wheat breeding for blast resistance.

Prediction of surface temperature and CO2 emission of leading emitters using grey model EGM (1,1, α, θ)

The current study projects the increase in surface temperature and CO₂ emissions using the EGM (1,1, α, θ) grey model for the six most significant CO₂ contributing countries, namely China, the USA, India, Russia, Japan, and Germany. The study uses time series data for surface temperature (in degree celsius) from 2010 to 2020, and CO₂ emission (metric tons per capita) data from 2009 to 2019. The empirical results show a downward trend in CO₂ emissions from Japan, Germany, the USA, and Russia by 2028. However, in the same time period, CO₂ emissions are expected to increase for India and remain nearly constant for China. This study indicates an increase in surface temperature at a significant rate in all the 6 countries: by 6.70 °C for China, 7.52 °C for Germany, 2.95 °C for India, 2.66 °C for Japan, 3.61 °C for Russia, and 13.48 °C for the USA by the end of 2028. The study compares the EGM (1,1, α, θ) grey model with the general EGM (1,1) grey model and finds that the EGM (1,1, α, θ) model performs better in both in-sample and out-of-sample forecasting. The paper also puts forward policy suggestions to mitigate, manage, and reduce increases in surface temperature as well as CO₂ emissions.

Dynamic assessment of oropharynx with ultrasonography as a screening tool for obstructive sleep apnea

Ultrasonography is an easily available and portable tool to assess the dynamic changes in the upper airway and surrounding soft tissue. This study aimed to evaluate the utility of oropharynx ultrasonography as a screening tool for obstructive sleep apnea (OSA). The study sequentially enrolled overweight individuals (body mass index >25 kg/m² ) and subjected them to OSA screening tools (Berlin questionnaire, Epworth Sleepiness Scale and STOP-Bang scores), ultrasonography of the oropharynx followed by overnight polysomnography. A total of 30 healthy individuals were also recruited as controls. Detailed dynamic and static ultrasonography measurements of the oropharynx and surrounding tissue were done. The diagnostic ability of various ultrasonography parameters to detect OSA was determined using receiver operating characteristic curve analysis. A total of 63 subjects were enrolled, with 33 in the OSA group and 30 in non-OSA overweight group. All baseline characteristics were similar in the two groups. Except for the dynamic measurements of oropharynx (Retropalatal% change-inspiration, retropalatal% change-Muller manoeuvre, retroglossal% change-inspiration, and retroglossal% change-Muller manoeuvre) all other parameters were similar in the OSA and non-OSA overweight subjects. The area under the receiver operating characteristic curve was highest for retropalatal% change-inspiration: 0.989, followed by retropalatal% change-Muller manoeuvre: 0.988. Both were also significant predictors of OSA with odds ratios of 0.338 (p = 0.003; 95% confidence interval [CI] 0.164-0.696) and 0.346 (p = 0.018; 95% CI 0.143-0.837), respectively. Ultrasonography provides a near complete picture of the dynamic changes and collapsibility of the oropharynx and can be an effective tool in screening for OSA.

Quasi-static indentation damage mechanics of PU foam core reinforced with fly ash particulate

The fly ash (FA) particulates are used in this study to reinforce the polyurethane foam (PUF) core. The FA particles inclusion improves the mechanical performance of the PUF core under compression by increasing its modulus of elasticity. Low-velocity impacts have damage dynamics that are pretty similar to quasi-static indentation. Consequently, the indentation resistance capability of the PUF core is investigated for three types of indenter nose tips with varied FA wt. Percentages (flat-circular, hemispherical, and conical). The results reveal that the reinforced foam core’s resistance varies with reinforcement percentage under indentation. However, FA reinforcement to PUF does not necessarily improve indentation resistance. The damage mechanism of the PUF core under indentation has been evaluated for each type of indenter. The interaction of crushing, shear, and tear of the damaged surface with the change in indenter nose tip has been explained with 0–20% variation of FA particles. Scanning electron microscope (SEM) images are taken for the analysis of the damaged PUF core cross-section at the indented location. Earlier mechanical findings of the scatter in deformation behavior with the indenter nose tip geometry are substantiated by the SEM studies.

Energy decomposition and waterswapping analysis to investigate the SNP associated DPD mediated 5-FU resistance

5-fluorouracil is an essential component of systemic chemotherapy for colon, breast, head, and neck cancer patients. However, tumoral overexpression of the dihydropyrimidine dehydrogenase has rendered 5-FU clinically ineffective by inactivating it to 5'-6'-dihydro fluorouracil. The responses to 5-FU in terms of efficacy and toxicity greatly differ depending upon the population group, because of variability in the DPD activity levels. In the current study, key active site amino acids involved in the 5-FU inactivation were investigated by modelling the 3D structure of human DPD in a complex with 5-FU. The identified amino acids were analyzed for their possible missense mutations available in dbSNP database. Out of 12 missense SNPs, four were validated either by sequencing in the 1000 Genomes project or frequency/genotype data. The recorded validated missense SNPs were further considered to analyze the effect of their respective alterations on 5-FU binding. Overall findings suggested that population bearing the Glu611Val DPD mutation (rs762523739) is highly vulnerable to 5-FU resistance. From the docking, electrostatic complementarity, dynamics, and energy decomposition analyses it was found that the above mutation showed superior scores than the wild DPD -5FU complex. Therefore, prescribing prodrug NUC-3373 or DPD inhibitors (Gimeracil/3-Cyano-2,6-Dihydroxypyridines) as adjuvant therapy may overcome the 5-FU resistance.