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1.
J Phys Condens Matter ; 36(50)2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39270719

RESUMO

Spin injection across 160 nm thick semi-crystalline Poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) is methodically investigated at room temperature in PVDF-HFP/NiFe bilayers and Ag/(NiFe or Co)/PVDF-HFP/NiFe vertical organic spin valves (OSVs) using both the co-planar waveguide ferromagnetic resonance (CPW-FMR: 7-35 GHz) and magnetoresistance (MR) techniques. The structural and microstructural characteristics of PVDF-HFP reveal the formation of mixed non-ferroelectric alpha and ferroelectric beta phases. The spin injection due to the transfer of angular momentum in PVDF-HFP/NiFe is quantified by measuring the spin-mixing conductance (g↑↓) and the enhancement in Gilbert damping (α) parameters from CPW-FMR data. A significant increase inαof 26% andg↑↓of (2.72 ± 0.45) × 1019m-2highlights the efficient spin injection into the PVDF-HFP spacer layer. Further, the MR in OSV structures reveals a room temperature spin injection with a maximum MR of 0.278 ± 0.006% for Ag/Co/PVDF-HFP/NiFe and 0.349 ± 0.039% for the Ag/NiFe/PVDF-HFP/NiFe devices. Furthermore, the spin injection processes are discussed w.r.t to bias voltages, interfaces and microwave frequencies.

2.
J Math Biol ; 89(2): 22, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951257

RESUMO

Group defense in prey and hunting cooperation in predators are two important ecological phenomena and can occur concurrently. In this article, we consider cooperative hunting in generalist predators and group defense in prey under a mathematical framework to comprehend the enormous diversity the model could capture. To do so, we consider a modified Holling-Tanner model where we implement Holling type IV functional response to characterize grazing pattern of predators where prey species exhibit group defense. Additionally, we allow a modification in the attack rate of predators to quantify the hunting cooperation among them. The model admits three boundary equilibria and up to three coexistence equilibrium points. The geometry of the nontrivial prey and predator nullclines and thus the number of coexistence equilibria primarily depends on a specific threshold of the availability of alternative food for predators. We use linear stability analysis to determine the types of hyperbolic equilibrium points and characterize the non-hyperbolic equilibrium points through normal form and center manifold theory. Change in the model parameters leading to the occurrences of a series of local bifurcations from non-hyperbolic equilibrium points, namely, transcritical, saddle-node, Hopf, cusp and Bogdanov-Takens bifurcation; there are also occurrences of global bifurcations such as homoclinic bifurcation and saddle-node bifurcation of limit cycles. We observe two interesting closed 'bubble' form induced by global bifurcations due to change in the strength of hunting cooperation and the availability of alternative food for predators. A three dimensional bifurcation diagram, concerning the original system parameters, captures how the alternation in model formulation induces gradual changes in the bifurcation scenarios. Our model highlights the stabilizing effects of group or gregarious behaviour in both prey and predator, hence supporting the predator-herbivore regulation hypothesis. Additionally, our model highlights the occurrence of "saltatory equilibria" in ecological systems and capture the dynamics observed for lion-herbivore interactions.


Assuntos
Ecossistema , Cadeia Alimentar , Conceitos Matemáticos , Modelos Biológicos , Dinâmica Populacional , Comportamento Predatório , Animais , Dinâmica Populacional/estatística & dados numéricos , Comportamento Cooperativo , Simulação por Computador , Herbivoria , Modelos Lineares
3.
Cell Mol Bioeng ; 17(3): 177-188, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39050513

RESUMO

Introduction: Natural killer (NK) cell-based therapies are a promising new method for treating indolent cancer, however engineering new therapies is complex and progress towards therapy for solid tumors is slow. New methods for determining the underlying intracellular signaling driving the killing phenotype would significantly improve this progress. Methods: We combined single-cell RNA sequencing with live cell imaging of a model system of NK cell killing to correlate transcriptomic data with functional output. A model of NK cell activity, the NK-92 cell line killing of HeLa cervical cancer cells, was used for these studies. NK cell killing activity was observed by microscopy during co-culture with target HeLa cells and killing activity subsequently manually mapped based on NK cell location and Annexin V expression. NK cells from this culture system were profiled by single-cell RNA sequencing using the 10× Genomics platform, and transcription factor activity inferred using the Viper and DoRothEA R packages. Luminescent microscopy of reporter constructs in the NK cells was then used to correlate activity of inferred transcriptional activity with killing activity. Results: NK cells had heterogeneous killing activity during 10 h of culture with target HeLa cells. Analysis of the single cell sequencing data identified Nuclear Factor Kappa B (NF-κB), Signal Transducer and Activator of Transcription 1 (STAT1) and MYC activity as potential drivers of NK cell functional phenotype in our model system. Live cell imaging of the transcription factor activity found NF-κB activity was significantly correlated with past killing activity. No correlation was observed between STAT1 or MYC activity and NK cell killing. Conclusions: Combining luminescent microscopy of transcription factor activity with single-cell RNA sequencing is an effective means of assigning functional phenotypes to inferred transcriptomics data. Supplementary Information: The online version contains supplementary material available at 10.1007/s12195-024-00812-3.

4.
J Biol Dyn ; 18(1): 2332279, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38517146

RESUMO

We investigate the dynamics of a prey-predator model with cooperative hunting among specialist predators and maturation delay in predator growth. First, we consider a model without delay and explore the effect of hunting time on the coexistence of predator and their prey. When the hunting time is long enough and the cooperation rate among predators is weak, prey and predator species tend to coexist. Furthermore, we observe the occurrences of a series of bifurcations that depend on the cooperation rate and the hunting time. Second, we introduce a maturation delay for predator growth and analyse its impact on the system's dynamics. We find that as the delay becomes larger, predator species become more likely to go extinct, as the long maturation delay hinders the growth of the predator population. Our numerical exploration reveals that the delay causes shifts in both the bifurcation curves and bifurcation thresholds of the non-delayed system.


Assuntos
Cadeia Alimentar , Modelos Biológicos , Animais , Dinâmica Populacional , Caça , Comportamento Predatório , Ecossistema
5.
Sci Rep ; 12(1): 20098, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36418377

RESUMO

The in-depth understanding of the dynamics of COVID-19 transmission among different age groups is of great interest for governments and health authorities so that strategies can be devised to reduce the pandemic's detrimental effects. We developed the SIRDV-Virulence (Susceptible-Infected-Recovered-Dead-Vaccinated-Virulence) epidemiological model based on a population balance equation to study the effects virus mutants, vaccination strategies, 'Anti/Non Vaxxer' proportions, and reinfection rates to provide methods to mitigate COVID-19 transmission among the United States population. Based on publicly available data, we obtain the key parameters governing the spread of the pandemic. The results show that a large fraction of infected cases comes from the adult and children populations in the presence of a highly infectious COVID-19 mutant. Given the situation at the end of July 2021, the results show that prioritizing children and adult vaccinations over that of seniors can contain the spread of the active cases, thereby preventing the healthcare system from being overwhelmed and minimizing subsequent deaths. The model suggests that the only option to curb the effects of this pandemic is to reduce the population of unvaccinated individuals. A higher fraction of 'Anti/Non-vaxxers' and a higher reinfection rate can both independently lead to the resurgence of the pandemic.


Assuntos
COVID-19 , Vírus da Influenza A Subtipo H1N1 , Adulto , Criança , Estados Unidos/epidemiologia , Humanos , Reinfecção/epidemiologia , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinação/métodos , Mutação
6.
Int J Legal Med ; 136(5): 1457-1467, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35503573

RESUMO

OBJECTIVE: The biochemical approach of dental age using aspartic acid racemization has been widely reported. The aim of this systematic review was to determine the reliability and accuracy of dental age estimation using aspartic acid racemization rate analysis. DESIGN: Eight research databases (PubMed, Google Scholar, Embase, Cochrane, MEDLINE, TRIP, Web of Science, and Scopus) were utilised to gather and assess published literatures in compliance with the PRISMA 2020 guidelines and reported in PROSPERO (CRD42020208877). This systematic review and meta-analysis focused solely on cross-sectional studies. The quality evaluation was performed using the GRADE system. The standardized mean difference between estimated and chronological age was meta-analyzed using the random effects model. RESULT: The literature review yielded 213 studies, of which 26 were considered acceptable for inclusion in this report. Out of 26 studies, 19 presented sufficient evidence for meta-analysis and the remaining 7 were used to construct a qualitative review. According to the meta-analysis, premolar-related studies had the least variability (Tau2 = 0.23; I2 = 72%) among other tooth groups. CONCLUSION: A substantial degree of heterogeneity was found in every type of tooth. Only the premolar teeth had lower degree variability; thus, it is safe to believe that the premolar tooth is the best for this type of age estimation. It is recommended to develop population-specific mathematical equations to improve the accuracy of this age estimation approach.


Assuntos
Determinação da Idade pelos Dentes , Ácido Aspártico , Estudos Transversais , Dentina/química , Humanos , Reprodutibilidade dos Testes
7.
Autops Case Rep ; 11: e2021295, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34458165

RESUMO

Forensic odontology is a specialty of dental sciences that deals with dental evidence in the interest of the justice system. The science of autopsy has been developing from the ancient times even before the popularization of general medicine. The objective of a medico-legal autopsy is to identify significant clues for an ongoing forensic investigation. However, in certain circumstances, it is difficult to conduct an oral examination owing to the anatomic location of the oral cavity. The onset of rigor mortis after death poses further complications. Thus, skillful and sequential dissections of the oral and para-oral structures are required to expose the dentition. Dental autopsy includes incisions and resection of the jaw for the detailed examination of the oral cavity. The procedure involves various modes of examination, including visual and radiographic, which help in human identification in forensic investigation. The present paper provides an overview of the various methods of dental autopsy.

8.
Front Physiol ; 12: 652799, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33995121

RESUMO

The pestilential pathogen SARS-CoV-2 has led to a seemingly ceaseless pandemic of COVID-19. The healthcare sector is under a tremendous burden, thus necessitating the prognosis of COVID-19 severity. This in-depth study of plasma proteome alteration provides insights into the host physiological response towards the infection and also reveals the potential prognostic markers of the disease. Using label-free quantitative proteomics, we performed deep plasma proteome analysis in a cohort of 71 patients (20 COVID-19 negative, 18 COVID-19 non-severe, and 33 severe) to understand the disease dynamics. Of the 1200 proteins detected in the patient plasma, 38 proteins were identified to be differentially expressed between non-severe and severe groups. The altered plasma proteome revealed significant dysregulation in the pathways related to peptidase activity, regulated exocytosis, blood coagulation, complement activation, leukocyte activation involved in immune response, and response to glucocorticoid biological processes in severe cases of SARS-CoV-2 infection. Furthermore, we employed supervised machine learning (ML) approaches using a linear support vector machine model to identify the classifiers of patients with non-severe and severe COVID-19. The model used a selected panel of 20 proteins and classified the samples based on the severity with a classification accuracy of 0.84. Putative biomarkers such as angiotensinogen and SERPING1 and ML-derived classifiers including the apolipoprotein B, SERPINA3, and fibrinogen gamma chain were validated by targeted mass spectrometry-based multiple reaction monitoring (MRM) assays. We also employed an in silico screening approach against the identified target proteins for the therapeutic management of COVID-19. We shortlisted two FDA-approved drugs, namely, selinexor and ponatinib, which showed the potential of being repurposed for COVID-19 therapeutics. Overall, this is the first most comprehensive plasma proteome investigation of COVID-19 patients from the Indian population, and provides a set of potential biomarkers for the disease severity progression and targets for therapeutic interventions.

9.
iScience ; 24(3): 102135, 2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33558857

RESUMO

The altered molecular proteins and pathways in response to COVID-19 infection are still unclear. Here, we performed a comprehensive proteomics-based investigation of nasopharyngeal swab samples from patients with COVID-19 to study the host response by employing simple extraction strategies. Few of the host proteins such as interleukin-6, L-lactate dehydrogenase, C-reactive protein, Ferritin, and aspartate aminotransferase were found to be upregulated only in COVID-19-positive patients using targeted multiple reaction monitoring studies. The most important pathways identified by enrichment analysis were neutrophil degranulation, interleukin-12 signaling pathways, and mRNA translation of proteins thus providing the detailed investigation of host response in COVID-19 infection. Thus, we conclude that mass spectrometry-detected host proteins have a potential for disease severity progression; however, suitable validation strategies should be deployed for the clinical translation. Furthermore, the in silico docking of potential drugs with host proteins involved in the interleukin-12 signaling pathway might aid in COVID-19 therapeutic interventions.

10.
J Forensic Leg Med ; 74: 102022, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33012311

RESUMO

BACKGROUND: - Tattoos refer to various skin markings done by impregnating the skin's epidermis with varied pigments. In forensic science, tattoos are considered as secondary identification markers and can be used for positive identification. Indian society is a unique blend of traditional and modern religious and social practices. Thus, traditional tattoos are still prevalent among various tribal societies and scheduled castes spread throughout various parts of India. The tribal tattoos can be used to determine tribal affiliations, that can aid in the process of forensic identification. On the other hand, tattoos comprising Western-influenced designs as well as individuals co-opting traditional designs gradually are becoming more popular in urbanized India. Understanding and documenting the various tattoo patterns prevalent throughout the tribal population and the modern metropolitan cities can help create a reference base line data for future forensic identification.


Assuntos
Cultura , Tatuagem , Ciências Forenses , Humanos , Reconhecimento de Identidade , Índia , Grupos Populacionais
11.
Biosystems ; 197: 104176, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32628979

RESUMO

In this article, we propose and analyse a predator-prey model where apart from direct predation the prey population is affected by the fear induced from predators. The reproduction of the prey population is reduced as a cost of fear. The predator is assumed to consume the prey according to ratio-dependent functional response and is also involved in intra-specific competition due to limited resources of food. Through model analysis, it has been observed that fear factor regulates the dynamics of the system in a completely different way than in the case where functional response is only prey dependent. Also, intra-specific competition among predators reduces the effect of fear and it forms a different pattern in the system dynamics than that of the effect of fear. Furthermore, the deterministic model has been extended to a stochastic model by perturbing the natural death rates of both prey and predators. It has been observed that the stochastic system possesses a unique positive solution that is globally stable with respect to anywhere in the interior of the positive quadrant. The stochastic extinction and persistence scenario for both the species have been analysed and a detailed comparison between the deterministic and stochastic models have been done through exhaustive numerical simulation. Finally, numerical simulation has been performed to figure out the impact of fear on the population dynamics.


Assuntos
Ecossistema , Medo , Cadeia Alimentar , Modelos Biológicos , Animais , Simulação por Computador , Extinção Biológica , Dinâmica Populacional , Comportamento Predatório , Processos Estocásticos
12.
J Forensic Dent Sci ; 11(1): 42-47, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31680755

RESUMO

INTRODUCTION: Teeth are invaluable in both the living and the deceased for forensic identification and profiling purposes. The occlusal surface patterns in the molars of an individual depend on both intrinsic and extrinsic factors. The individualistic nature of the groove pattern can be used to determine the identity of an individual by the process of comparative identification. AIM AND OBJECTIVE: The objective of this study is to determine the uniqueness of the groove pattern among individuals by the means of digital analysis. MATERIALS AND METHODS: An experimental study was conducted on 80 dental casts where the occlusal groove patterns of 1st and 2nd molars from each cast were traced digitally using image analysis software GIMP (v 2.10.6). The traced patterns were then examined to determine their uniqueness. RESULTS: The most common groove patterns for the maxillary 1st and 2nd molars were found to resemble "Branched H" and "H", respectively. "Y" pattern was observed to be the most common in mandibular 1st molar, whereas mandibular 2nd molar most commonly exhibited "+" pattern. No two groove patterns were similar in the analysis. CONCLUSION: Digital method of analysis is preferable over conventional manual methods as it is noninvasive and precise. The individualistic nature of occlusal groove patterns may play an important role in comparative forensic identification.

13.
Coll Antropol ; 36(3): 929-36, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23213954

RESUMO

The present study has been carried out on 795 Baiga children (453 males and 342 females) of Baiga-chak area of Dindori district in Madhya Pradesh (MP) varying between 1-18 years of age with an aim to understand their growth profile using cross sectional design. Fourteen body measurements (weight, height, sitting height, lengths, breadths, circumferences and skin folds) were studied. Four indices namely Sitting height/Leg length, Bicristal breadth/Biacro-mial breadth, Head circumference/Chest circumference & Cephalic index were computed to study the proportionate body changes. All body measurements except for skin folds increased progressively in each age group showing insignificant difference between boys and girls in most of age groups with no evident peak velocity during pubertal age in both sexes. However skin folds showed inconsistent pattern with each successive age. The present children were slightly heavier and taller than tribal children of other areas but lighter and shorter than Bharia children. However, these children were comparable with all India rural children but found below 10th percentile when compared with National Centre for Health Statistics (NCHS) standards. The absence of peak velocity and poor growth in studied children may be due to low intensity of growth rate. Proportionate changes observed in the present study were similar to Indian Punjabi girls.


Assuntos
Antropometria , Desenvolvimento Infantil , Gráficos de Crescimento , Grupos Populacionais , População Rural , Adolescente , Criança , Pré-Escolar , Feminino , Geografia , Humanos , Índia , Lactente , Masculino
14.
Ann Hum Biol ; 38(6): 685-90, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21864082

RESUMO

BACKGROUND: Reliable reports on growth impairment in sickle cell trait (SCT) children in India are lacking despite contradictory findings reported earlier. AIM: The present study assessed the impact of SCT on physical growth of tribal children of Mandla district. SUBJECTS AND METHODS: Weight, height, circumferences, breadths, lengths and skinfolds were recorded on 6190 children, inclusive of 732 SCT children, from birth to 12 years of age using a cross-sectional design. The sickle test was conducted in the field using 2% sodium metabisulphite followed by electrophoresis. RESULTS: No significant difference in mean values was observed in the majority of the age groups between SCT and normal children for all 11 body measurements. However, inconsistent growth patterns in these measurements among SCT children were evident. Body weight was more deficient than height or other body measurements in the children when compared to Indian and National Centre for Health Statistics (NCHS) standards, while bicristal breadth was comparable with Indian standards. CONCLUSIONS: There was no significant impact of SCT observed on growth of children irrespective of sex. Notably, growth of SCT girls was comparable to their normal counterparts. The actual growth difference between normal and SCT children may have been masked on account of poor attainment of annual gain in each successive age group.


Assuntos
Crescimento e Desenvolvimento/fisiologia , Grupos Populacionais , Traço Falciforme/fisiopatologia , Distribuição por Idade , Estatura/fisiologia , Peso Corporal/fisiologia , Cefalometria , Criança , Pré-Escolar , Feminino , Geografia , Humanos , Índia , Lactente , Recém-Nascido , Masculino , Dobras Cutâneas
15.
Rural Remote Health ; 7(2): 605, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17511523

RESUMO

INTRODUCTION: Indian tribal men's lack of participation in reproductive health not only damages their own health, but also contributes to the reproductive ill health of their female partners and children. In India the involvement of men in such matters is a new concept. There is a paucity of data particularly on Scheduled tribesmen's knowledge and the extent of their participation in reproductive health. This inhibits planning. The present study aims to understand the involvement of Scheduled tribesmen in reproductive health and the barriers to their involvement by generating a database from the Khairwar tribe of Central India. METHODS: A door-to-door survey on knowledge, attitude and practice relating to aspects of reproductive health was conducted by canvassing a pre-designed interview schedule among 15-40 year old, currently married Khairwar males in the Sidhi district of Madhya Pradesh, India. RESULTS: As far as reproductive morbidity is concerned, only 17% of the respondents had heard of HIV/AIDS, and most had no proper knowledge of its transmission. Although 74% of the respondents had heard about reproductive tract infections, the majority of them were unaware of the mechanism of transmission and seriousness of the problem. The duel role of condoms, both as a method of family planning and a protective measure against sexually transmitted infections, was also unknown to them. Approximately 59% of the males were aware of family planning but only 13% were using any method (mostly female sterilization) at the time of survey. Their view on the ideal number of children (3.56) exceeded the actual number of children born and living. High infant and child mortality influenced their preference for higher fertility. Very few among them (29%) had knowledge of antenatal care. They expressed faulty knowledge, myths and unhelpful attitudes towards sexual health matters. CONCLUSION: The study revealed the male Scheduled tribe population's lack of knowledge and misinformation regarding male sexual health issues, the gender inequality in Indian society, and a lack of male-oriented reproductive health services, all of which deter men from sharing the responsibility.


Assuntos
Comportamentos Relacionados com a Saúde/etnologia , Conhecimentos, Atitudes e Prática em Saúde , Comportamento Sexual/etnologia , Adolescente , Adulto , Comportamento Contraceptivo/etnologia , Feminino , Inquéritos Epidemiológicos , Humanos , Índia/epidemiologia , Masculino , Estado Civil/etnologia , População Rural/estatística & dados numéricos , Sexo Seguro/etnologia , Infecções Sexualmente Transmissíveis/etnologia , Infecções Sexualmente Transmissíveis/prevenção & controle
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