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1.
Nanotechnology ; 35(30)2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38631308

RESUMO

We have experimentally demonstrated spatially selective absorption in Ag-SiO2-Ag based trilayer thin films by tuning the deposition angle of SiO2layer. These structures generate cavity resonance which can be tuned across the substrate locations due to spatially selective thickness and refractive index of silicon oxide (SiO2) film sandwiched between metallic silver (Ag) mirrors. Spatially selective property of SiO2film is obtained by oblique angle deposition technique using an electron beam evaporation system. The resonance wavelength of absorption in this trilayer structure shifts across the substrate locations along the direction of oblique deposition. The extent of shift in resonance increases with increase in angle of deposition of SiO2layer. 4.14 nm mm-1average shift of resonance wavelength is observed when SiO2is deposited at 40° whereas 4.76 nm mm-1average shift is observed when SiO2is deposited at 60°. We observed that the width of resonance increases with angle of deposition of the cavity layer and ultimately the resonant absorption disappears and becomes broadband when SiO2is deposited at glancing angle deposition (GLAD) configuration. Our study reveals that there is a suitable range of oblique angle of deposition from 40° to 60° for higher spatial tunability and resonant absorption whereas the absorption becomes broadband for glancing angle deposition.

2.
Clin Case Rep ; 12(2): e8480, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38328489

RESUMO

Patients mimicking appendicitis symptoms in a rural setting or those post-appendectomy, indicating cecal volvulus, should always be considered. Swift action can prevent catastrophic consequences. Abstract: We present a case of a 14-year-old female who initially underwent open appendectomy for acute appendicitis and subsequently experienced symptoms of abdominal distention, vomiting, and fever. Her condition deteriorated following the appendectomy, despite a prior appendectomy for similar symptoms at a different facility. A computed tomography (CT) scan identified cecal volvulus as the underlying issue. This led to the performance of a laparotomy, cecopexy, and decompressive ileostomy. After six weeks, ileostomy closure was successfully carried out, and the patient currently enjoys good health. This case highlights the significance of considering uncommon factors as potential contributors to postoperative complications in young patients.

3.
J Radiol Prot ; 43(3)2023 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-37402358

RESUMO

The study presents a novel approach to analysing the thermoluminescence (TL) glow curves (GCs) of CaSO4:Dy-based personnel monitoring dosimeters using machine learning (ML). This study demonstrates the qualitative and quantitative impact of different types of anomalies on the TL signal and trains ML algorithms to estimate correction factors (CFs) to account for these anomalies. The results show a good degree of agreement between the predicted and actual CFs, with a coefficient of determination greater than 0.95, a root mean square error less than 0.025, and a mean absolute error less than 0.015. The use of ML algorithms leads to a significant two-fold reduction in the coefficient of variation of TL counts from anomalous GCs. This study proposes a promising approach to address anomalies caused by dosimeter, reader, and handling-related factors. Furthermore, it accounts for non-radiation-induced TL at low dose levels towards improving the dosimetric accuracy in personnel monitoring.


Assuntos
Dosímetros de Radiação , Dosimetria Termoluminescente , Algoritmos
4.
BMC Plant Biol ; 22(1): 620, 2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36581797

RESUMO

BACKGROUND: Protein, starch, amylose and total soluble sugars are basic metabolites of seed that influence the eating, cooking and nutritional qualities of rice. Chlorophyll is responsible for the absorption and utilization of the light energy influencing photosynthetic efficiency in rice plant. Mapping of these traits are very important for detection of more number of robust markers for improvement of these traits through molecular breeding approaches. RESULTS: A representative panel population was developed by including 120 germplasm lines from the initial shortlisted 274 lines for mapping of the six biochemical traits using 136 microsatellite markers through association mapping. A wide genetic variation was detected for the traits, total protein, starch, amylose, total soluble sugars, chlorophyll a, and chlorophyll b content in the population. Specific allele frequency, gene diversity, informative markers and other diversity parameters obtained from the population indicated the effectiveness of utilization of the population and markers for mapping of these traits. The fixation indices values estimated from the population indicated the existence of linkage disequilibrium for the six traits. The population genetic structure at K = 3 showed correspondence with majority of the members in each group for the six traits. The reported QTL, qProt1, qPC6.2, and qPC8.2 for protein content; qTSS8.1 for total soluble sugar; qAC1.2 for amylose content; qCH2 and qSLCHH for chlorophyll a (Chl. a) while qChl5D for chlorophyll b (Chl. b) were validated in this population. The QTL controlling total protein content qPC1.2; qTSS7.1, qTSS8.2 and qTSS12.1 for total soluble sugars; qSC2.1, qSC2.2, qSC6.1 and qSC11.1 for starch content; qAC11.1, qAC11.2 and qAC11.3 for amylose content; qChla8.1 for Chl. a content and qChlb7.1 and qChlb8.1 for Chl. b identified by both Generalized Linear Model and Mixed Linear Model were detected as novel QTL. The chromosomal regions on chromosome 8 at 234 cM for grain protein content and total soluble sugars and at 363 cM for Chl. a and Chl. b along with the position at 48 cM on chromosome 11 for starch and amylose content are genetic hot spots for these traits. CONCLUSION: The validated, co-localized and the novel QTL detected in this study will be useful for improvement of protein, starch, amylose, total soluble sugars and chlorophyll content in rice.


Assuntos
Oryza , Amido , Amido/química , Amilose/metabolismo , Oryza/metabolismo , Clorofila A , Clorofila , Açúcares
5.
Funct Integr Genomics ; 22(5): 743-756, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35718806

RESUMO

Heat shock transcription factors (Hsfs) play an essential role as transcriptional regulatory proteins against heat stress by controlling the expression of heat-responsive genes. Common bean is a highly thermosensitive crop, and, therefore, its genome sequence information is segregated, characterized here in terms of heat shock transcription factors and its evolutionary significance. In this study, a complete comprehensive set of 29 non-redundant full-length Hsf genes were identified and characterized from Phaseolus vulgaris L. (PvHsf) genome sequence. Detailed gene information such as chromosomal localization, domain position, motif organization, and exon-intron identification were analyzed. All the 29 PvHsf genes were mapped on 8 out of 11 chromosomes, indicating the gene duplication occurred in the common bean genome. Motif analysis and exon-intron structure were conserved in each group, which showed that the cytoplasmic proteins highly influence the conserved structure of PvHsfs and heat-induced response. The HSF genes were grouped into three classes, i.e., A to C and 14 groups, based on structural features and phylogenetic relationships. Only one pair of paralog sequences suggests that it may be derived from the duplication event during evolution. A comparative genomics study indicated the influence of whole-genome duplication and purifying selection on the common bean genome during development. In silico expression analysis showed the active role of class A and B family during abiotic stress conditions and higher expression in floral organs. The qRT-PCR analysis revealed PvHSFA8 as the master regulator and PvHSFB1A and PvHSFB2A induction during heat exposure in French beans.


Assuntos
Phaseolus , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Fatores de Transcrição de Choque Térmico/genética , Fatores de Transcrição de Choque Térmico/metabolismo , Phaseolus/genética , Phaseolus/metabolismo , Filogenia , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética
6.
J Laryngol Otol ; 136(9): 823-826, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35443898

RESUMO

OBJECTIVE: To determine if otolaryngologists and audiologists of the American Academy of Otolaryngology - Head and Neck Surgery have noticed an increase in the incidence of sudden sensorineural hearing loss during the coronavirus disease 2019 pandemic. METHODS: A questionnaire was developed for the purpose of providing a cross-sectional descriptive analysis of perceived association between the coronavirus disease 2019 pandemic and an increase in the incidence of sudden sensorineural hearing loss. RESULTS: Of respondents, 63.0 per cent did not notice an increase in sudden sensorineural hearing loss during the coronavirus disease 2019 pandemic. There was a weak positive correlation between patients identified with sudden sensorineural hearing loss and the percentage of coronavirus disease 2019 positive patients reported by each medical care provider (Spearman correlation = 0.20, 95 per cent confidence interval = 0.05-0.33). There was no association between geographical location and perceived increase in sudden sensorineural hearing loss (p = 0.38). CONCLUSION: The majority of respondents did not perceive an increase in the incidence of sudden sensorineural hearing loss during the coronavirus pandemic, regardless of geographical region.


Assuntos
COVID-19 , Perda Auditiva Neurossensorial , Perda Auditiva Súbita , COVID-19/complicações , COVID-19/epidemiologia , Estudos Transversais , Perda Auditiva Neurossensorial/etiologia , Perda Auditiva Súbita/epidemiologia , Perda Auditiva Súbita/etiologia , Humanos , Pandemias
7.
Kathmandu Univ Med J (KUMJ) ; 20(79): 301-306, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37042370

RESUMO

Background Gingivitis simply means the inflammation of gingiva. It is a reversible state but can lead to periodontitis. The final result could be the exfoliation of the tooth causing decreased masticatory function leading to a compromised quality of life. Gingivitis in the pregnant woman should be carefully assessed and treated and given special attention. There is rare documentation on the prevalence of gingivitis in pregnancy in the least developed countries. Objective To evaluate the prevalence of gingivitis in the second trimester of pregnancy and assess its relationship with age, parity, education, occupation, gravidity, oral hygiene habit and frequency of brushing. Method An observational descriptive study was conducted among 384 pregnant females in their second trimester in Kathmandu, Nepal. Demographic variables and general information including those related to oral hygiene practices and habits were collected during an interview. Plaque index and Gingival Index was recorded among the patients through full mouth examination at four sites. Result The prevalence of gingivitis in the second trimester of pregnancy was 76.3%. Statistically significant relationship was found between gingivitis and gravida and parity. A relation could not be established between gingivitis with age, education, occupation, oral hygiene habit and frequency of brushing. Conclusion The prevalence of gingivitis is found to be high in Nepalese pregnant women. Special strategies should be introduced targeting the pregnant women of least developed countries to uplift their periodontal health.


Assuntos
Gengivite , Qualidade de Vida , Feminino , Humanos , Gravidez , Gengivite/etiologia , Paridade , Segundo Trimestre da Gravidez , Prevalência
8.
Clin Exp Dermatol ; 47(3): 516-521, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34480806

RESUMO

Leishmaniasis is broadly classified into three types: cutaneous, mucocutaneous and visceral. The visceral form is most dangerous and can result in death. Although leishmaniasis is an ancient disease, its treatment is still challenging. Several drugs, differing in their cost, toxicity, treatment duration and emergence of drug resistance, are used for different types of leishmaniasis. To overcome these limitations, the search for newer drugs and other treatments continues. In this article, we discuss conventional drugs, other treatments, including newer options such as immunotherapy and immunochemotherapy, and future prospects for leishmaniasis treatment.


Assuntos
Leishmaniose/terapia , Antiprotozoários/uso terapêutico , Terapia Combinada , Crioterapia , Quimioterapia Combinada , Temperatura Alta/uso terapêutico , Humanos , Imunoterapia , Leishmaniose/tratamento farmacológico , Fotoquimioterapia
9.
AJNR Am J Neuroradiol ; 43(1): 125-131, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34764083

RESUMO

BACKGROUND AND PURPOSE: Gamma-aminobutyric acid and glutamate system disruptions may underlie neonatal brain injury. However, in vivo investigations are challenged by the need for special 1H-MR spectroscopy sequences for the reliable measurement of the neurotransmitters in this population. We used J-edited 1H-MR spectroscopy (Mescher-Garwood point-resolved spectroscopy) to quantify regional in vivo gamma-aminobutyric acid and glutamate concentrations during the early postnatal period in healthy neonates. MATERIALS AND METHODS: We prospectively enrolled healthy neonates and acquired Mescher-Garwood point-resolved spectroscopy spectra on a 3T MR imaging scanner from voxels located in the cerebellum, the right basal ganglia, and the right frontal lobe. CSF-corrected metabolite concentrations were compared for regional variations and cross-sectional temporal trends with advancing age. RESULTS: Fifty-eight neonates with acceptable spectra acquired at postmenstrual age of 39.1 (SD, 1.3) weeks were included for analysis. Gamma-aminobutyric acid (+ macromolecule) (2.56 [SD, 0.1]) i.u., glutamate (3.80 [SD, 0.2]), Cho, and mIns concentrations were highest in the cerebellum, whereas NAA (6.72 [SD, 0.2]), NAA/Cho, Cr/Cho, and Glx/Cho were highest in the basal ganglia. Frontal gamma-aminobutyric acid (1.63 [SD, 0.1]), Glx (4.33 [SD, 0.3]), Cr (3.64 [SD, 0.2]), and Cho concentrations were the lowest among the ROIs. Glx, NAA, and Cr demonstrated a significant adjusted increase with postmenstrual age (ß = 0.2-0.35), whereas gamma-aminobutyric acid and Cho did not. CONCLUSIONS: We report normative regional variations and temporal trends of in vivo gamma-aminobutyric acid and glutamate concentrations reflecting the functional and maturational status of 3 distinct brain regions of the neonate. These measures will serve as important normative values to allow early detection of subtle neurometabolic alterations in high-risk neonates.


Assuntos
Ácido Glutâmico , Ácido gama-Aminobutírico , Ácido Aspártico/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Estudos Transversais , Ácido Glutâmico/metabolismo , Humanos , Lactente , Recém-Nascido , Espectroscopia de Ressonância Magnética/métodos , Ácido gama-Aminobutírico/metabolismo
10.
Kathmandu Univ Med J (KUMJ) ; 20(80): 461-466, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37795725

RESUMO

Background Periodontitis is the common oral condition which affects the periodontium of the teeth that leads to destruction of periodontal ligaments and alveolar bone. Open flap debridement is the surgical procedure which provides access and visibility of the site, application of laser as an adjunct has various advantanges. Objective To compare clinical outcomes after open flap debridement with or without diode laser. Method Patients aged 25-45 years diagnosed with infrabony defect ≥ 5 mm visiting Department of Dental Surgery, Bir Hospital. Control group sites were treated with open flap debridement alone, whereas test-groups were treated with Open flap debridement with diode laser. Various parameters like Plaque index, Gingival index, Pocket depth and Clinical attachment level were assessed and compared between groups at baseline, 3 and 6 months. Result The mean plaque and gingival scores improved in both the control and test groups at 3 and 6 months follow up as compared to baseline and was statistically nonsignificant between two groups. Open flap debridement with or without diode laser in the treatment of periodontal intrabony defects did not produce significant reduction in pocket depth and gain in clinical attachment level. Conclusion There was no significant differences in the clinical parameters were seen in the surgical flap debridement of infrabony pocket with and without diode laser. Diode laser can be used safely as an adjunct. However, long-term, multicentric, histologic and microbial studies are required.


Assuntos
Perda do Osso Alveolar , Humanos , Perda do Osso Alveolar/cirurgia , Seguimentos , Desbridamento/métodos , Lasers Semicondutores/uso terapêutico , Bolsa Periodontal/cirurgia , Perda da Inserção Periodontal/cirurgia , Retalhos Cirúrgicos/cirurgia , Resultado do Tratamento
11.
Kathmandu Univ Med J (KUMJ) ; 19(74): 168-172, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34819430

RESUMO

Background Endodontics is considered as one of the most difficult and stressful disciplines in dentistry. This might be due to the complex anatomical variations, recent advances in equipment, technology, materials and lack of self-confidence. Objective To determine the self-confidence level among the intern dentists in performing endodontic procedures from six different colleges of Kathmandu University, Nepal. Method A descriptive cross-sectional study was conducted among 145 intern dentists. The online questionnaire regarding confidence level (5 point Likert scale) in different endodontic procedures and difficulty level (easy, ok and difficult) with respect to teeth was distributed. For descriptive purpose, frequency and percentage for each response were calculated. Result Dental interns were confident in performing majority of the normal endodontic procedures, however, they showed less confidence in performing difficult steps like rubber dam application for anterior (74, 51%) and posterior tooth (91, 62.7%), use of electronic apex locator (89, 61.4%), using rotary files (114, 78.6%), management of flare-ups (86, 59.4%), assessment of quality of post-endodontic treatment (85, 58.5%), recall periods (75, 51.6%) and performing post and core (82, 56.6%). Likewise, upper first molars (84, 57.9%) and second molars (104, 71.7%) were found to be the most difficult teeth to treat. Conclusion It can be concluded that majority of the dental interns were confident in performing basic endodontic procedures, however, they were found to have low confidence in performing difficult steps. Further training and exposure should be incorporated to increase their confidence level.


Assuntos
Endodontia , Tratamento do Canal Radicular , Estudos Transversais , Odontólogos , Humanos , Nepal , Inquéritos e Questionários
12.
Pediatr Cardiol ; 42(8): 1740-1748, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34136951

RESUMO

An unobstructed Fontan pathway is essential for optimal hemodynamics. We hypothesize that more extracardiac conduit (ECC) Fontan pathways develop obstruction compared to lateral tunnel (LT) Fontans and that the dilation typically observed in LTs results in similar mid-term clinical outcomes. A single-center, retrospective study was done including all Fontan cardiac catheterizations from 2006 to 2019. Angiography and medical records were reviewed to define Fontan pathway dimensions, interventions, and clinical outcomes. 232 patients underwent cardiac catheterization, where 60% were ECCs and 30% LTs. The minimum cross-sectional area (CSA) of ECCs was significantly smaller than LTs and LTs dilated over time. 13% of patients had Fontan pathway stenting at a median age of 16.2 years. The minimum CSA for patients who underwent intervention was significantly smaller than patients who did not. Lower weight at Fontan surgery was associated with intervention on the Fontan pathway, with a threshold weight of 15 kg for patients with an ECC. The median follow-up was 3.3 years. Patients who had Fontan pathway intervention were not more likely to experience the composite adverse clinical outcome. LTs were more likely than ECCs to have worse clinical outcome, when liver fibrosis was included. This is the first study to describe angiographic dimensions of the Fontan pathway in a large number of patients over time. ECCs tend to become stenotic. Lower weight at Fontan surgery is a potential risk for Fontan pathway intervention. LTs may experience worse clinical outcomes in follow-up. This information can help inform the optimal timing and method of post-Fontan surveillance.


Assuntos
Técnica de Fontan , Cardiopatias Congênitas , Adolescente , Cateterismo Cardíaco , Catéteres , Cardiopatias Congênitas/diagnóstico por imagem , Cardiopatias Congênitas/cirurgia , Humanos , Estudos Retrospectivos , Resultado do Tratamento
13.
Artigo em Inglês | MEDLINE | ID: mdl-34077364

RESUMO

Effective clinical trials for neuroprotective interventions for Parkinson's disease (PD) require a way to quantify an individual's motor symptoms and analyze the change in these symptoms over time. Clinical scales provide a global picture of function but cannot precisely measure specific aspects of motor control. We have used commercially available sensors to create a protocol called ASAP (Advanced Sensing for Assessment of Parkinson's disease) to obtain a quantitative and reliable measure of motor impairment in early to moderate PD. The ASAP protocol measures grip force as an individual tracks a sinusoidal or pseudorandom target force under three conditions of increasing cognitive load. Thirty individuals with PD have completed the ASAP protocol. The ASAP data for 26 of these individuals were summarized in terms of 36 variables, and modified regression techniques were used to predict an individual's score on the Unified Parkinson Disease Rating Scale based on ASAP data. We observed a mean prediction error of approximately 3.5 UPDRS points, and the predicted score accounted for approximately 76% of the variability of the UPDRS. These results demonstrate that the ASAP protocol can measure differences for individuals who are clinically different. This indicates that the ASAP protocol may be able to measure changes with time in the motor signs of an individual with PD.

14.
PLoS One ; 16(3): e0246232, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33647046

RESUMO

Iron (Fe) toxicity is a major abiotic stress which severely reduces rice yield in many countries of the world. Genetic variation for this stress tolerance exists in rice germplasms. Mapping of gene(s)/QTL controlling the stress tolerance and transfer of the traits into high yielding rice varieties are essential for improvement against the stress. A panel population of 119 genotypes from 352 germplasm lines was constituted for detecting the candidate gene(s)/QTL through association mapping. STRUCTURE, GenAlEx and Darwin softwares were used to classify the population. The marker-trait association was detected by considering both the Generalized Linear Model (GLM) and Mixed Linear Model (MLM) analyses. Wide genetic variation was observed among the genotypes present in the panel population for the stress tolerance. Linkage disequilibrium was detected in the population for iron toxicity tolerance. The population was categorized into three genetic structure groups. Marker-trait association study considering both the Generalized Linear Model (GLM) and Mixed Linear Model (MLM) showed significant association of leaf browning index (LBI) with markers RM471, RM3, RM590 and RM243. Three novel QTL controlling Fe-toxicity tolerance were detected and designated as qFeTox4.3, qFeTox6.1 and qFeTox10.1. A QTL reported earlier in the marker interval of C955-C885 on chromosome 1 is validated using this panel population. The present study showed that QTL controlling Fe-toxicity tolerance to be co-localized with the QTL for Fe-biofortification of rice grain indicating involvement of common pathway for Fe toxicity tolerance and Fe content in rice grain. Fe-toxicity tolerance QTL qFeTox6.1 was co-localized with grain Fe-biofortification QTLs qFe6.1 and qFe6.2 on chromosome 6, whereas qFeTox10.1 was co-localized with qFe10.1 on chromosome 10. The Fe-toxicity tolerance QTL detected from this mapping study will be useful in marker-assisted breeding programs.


Assuntos
Cromossomos de Plantas/genética , Tolerância a Medicamentos/genética , Genética Populacional , Ferro/toxicidade , Oryza/genética , Locos de Características Quantitativas , Mapeamento Cromossômico , Oryza/efeitos dos fármacos , Fenótipo , Melhoramento Vegetal
15.
Mater Sci Eng C Mater Biol Appl ; 120: 111697, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33545856

RESUMO

In the present study, a magnetic nanocomposite (magnetite Fe3O4 and hematite Fe2O3) has been successfully synthesized by the sol-gel method and coated with polyvinyl alcohol (PVA) followed by conjugation of anti-diabetic drug metformin. Detailed structural and microstructural characterization of the nanocomposite (NP) and drug conjugated nanocomposite (NP-DC) are analyzed by the Rietveld refinement of respective XRD patterns, FTIR analysis, UV-Vis spectroscopy, SEM and TEM results. SEM and TEM image analyses reveal the spherical morphology and average size of NP, PVA coated nanoparticles (NP-PVA) and NP-DC samples, indicating a suitable size to be a nanocarrier. The biocompatibility of NP and NP-DC was carried out in NIH/3T3 and J774A. 1 cells. The enhanced activity of the drug, when conjugated with nanocomposite, is confirmed after the treatment of both the pure drug and NP-DC sample on the 18 h fasted normoglycemic and hyperglycemic mice. The blood glucose level of the mice is effectively decreased with the same concentration of the pure drug and NP-DC sample. It proves the increased activity of the NP-DC sample, as only 5 wt% drug is present that shows the same efficiency as the pure drug. This study suggests excellent biocompatibility and cytocompatibility of NP and NP-DC besides the critical property as a hypoglycemic agent. It is the first time approach of conjugating metformin with a magnetic nanocomposite for a significant increment of its hypoglycemic activity, which is very important to reduce the side effect of metformin for its prolonged use.


Assuntos
Nanocompostos , Preparações Farmacêuticas , Animais , Hipoglicemiantes/farmacologia , Fenômenos Magnéticos , Magnetismo , Camundongos
16.
Radiat Prot Dosimetry ; 192(3): 299-308, 2020 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-33313924

RESUMO

In this study, the Bayesian probabilistic approach is applied for the estimation of the actual dose using personnel monitoring dose records of occupational workers. To implement the Bayesian approach, the probability distribution of the uncertainty in the reported dose as a function of the actual dose is derived. Using the uncertainty distribution function of reported dose and prior knowledge of dose levels generally observed in a monitoring period, the posterior probability distribution of the actual dose is estimated. The posterior distributions of each monitoring period in a year are convoluted to arrive at actual annual dose distribution. The estimated actual doses distributions show a significant deviation from reported annual doses particularly for low annual doses.


Assuntos
Radiometria , Teorema de Bayes , Humanos , Exposição Ocupacional , Probabilidade , Incerteza
17.
Radiat Prot Dosimetry ; 190(3): 342-351, 2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32857133

RESUMO

In the present study, machine learning (ML) methods for the identification of abnormal glow curves (GC) of CaSO4:Dy-based thermoluminescence dosimeters in individual monitoring are presented. The classifier algorithms, random forest (RF), artificial neural network (ANN) and support vector machine (SVM) are employed for identifying not only the abnormal glow curve but also the type of abnormality. For the first time, the simplest and computationally efficient algorithm based on RF is presented for GC classifications. About 4000 GCs are used for the training and validation of ML algorithms. The performance of all algorithms is compared by using various parameters. Results show a fairly good accuracy of 99.05% for the classification of GCs by RF algorithm. Whereas 96.7% and 96.1% accuracy is achieved using ANN and SVM, respectively. The RF-based classifier is recommended for GC classification as well as in assisting the fault determination of the TLD reader system.


Assuntos
Algoritmos , Dosímetros de Radiação , Aprendizado de Máquina , Redes Neurais de Computação , Máquina de Vetores de Suporte
18.
Mater Today Bio ; 7: 100065, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32613186

RESUMO

Nature provides an incredible source of inspiration, structural concepts, and materials toward applications to improve the lives of people around the world, while preserving ecosystems, and addressing environmental sustainability. In particular, materials derived from animal and plant sources can provide low-cost, renewable building blocks for such applications. Nature-derived materials are of interest for their properties of biodegradability, bioconformability, biorecognition, self-repair, and stimuli response. While long used in tissue engineering and regenerative medicine, their use in functional devices such as (bio)electronics, sensors, and optical systems for healthcare and biomonitoring is finding increasing attention. The objective of this review is to cover the varied nature derived and sourced materials currently used in active biodevices and components that possess electrical or electronic behavior. We discuss materials ranging from proteins and polypeptides such as silk and collagen, polysaccharides including chitin and cellulose, to seaweed derived biomaterials, and DNA. These materials may be used as passive substrates or support architectures and often, as the functional elements either by themselves or as biocomposites. We further discuss natural pigments such as melanin and indigo that serve as active elements in devices. Increasingly, combinations of different biomaterials are being used to address the challenges of fabrication and performance in human monitoring or medicine. Finally, this review gives perspectives on the sourcing, processing, degradation, and biocompatibility of these materials. This rapidly growing multidisciplinary area of research will be advanced by a systematic understanding of nature-inspired materials and design concepts in (bio)electronic devices.

20.
BMC Plant Biol ; 20(1): 57, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32019504

RESUMO

BACKGROUND: High yielding rice varieties are usually low in grain iron (Fe) and zinc (Zn) content. These two micronutrients are involved in many enzymatic activities, lack of which cause many disorders in human body. Bio-fortification is a cheaper and easier way to improve the content of these nutrients in rice grain. RESULTS: A population panel was prepared representing all the phenotypic classes for grain Fe-Zn content from 485 germplasm lines. The panel was studied for genetic diversity, population structure and association mapping of grain Fe-Zn content in the milled rice. The population showed linkage disequilibrium showing deviation of Hardy-Weinberg's expectation for Fe-Zn content in rice. Population structure at K = 3 categorized the panel population into distinct sub-populations corroborating with their grain Fe-Zn content. STRUCTURE analysis revealed a common primary ancestor for each sub-population. Novel quantitative trait loci (QTLs) namely qFe3.3 and qFe7.3 for grain Fe and qZn2.2, qZn8.3 and qZn12.3 for Zn content were detected using association mapping. Four QTLs, namely qFe3.3, qFe7.3, qFe8.1 and qFe12.2 for grain Fe content were detected to be co-localized with qZn3.1, qZn7, qZn8.3 and qZn12.3 QTLs controlling grain Zn content, respectively. Additionally, some Fe-Zn controlling QTLs were co-localized with the yield component QTLs, qTBGW, OsSPL14 and qPN. The QTLs qFe1.1, qFe3.1, qFe5.1, qFe7.1, qFe8.1, qZn6, qZn7 and gRMm9-1 for grain Fe-Zn content reported in earlier studies were validated in this study. CONCLUSION: Novel QTLs, qFe3.3 and qFe7.3 for grain Fe and qZn2.2, qZn8.3 and qZn12.3 for Zn content were detected for these two traits. Four Fe-Zn controlling QTLs and few yield component QTLs were detected to be co-localized. The QTLs, qFe1.1, qFe3.1, qFe5.1, qFe7.1, qFe8.1, qFe3.3, qFe7.3, qZn6, qZn7, qZn2.2, qZn8.3 and qZn12.3 will be useful for biofortification of the micronutrients. Simultaneous enhancement of Fe-Zn content may be possible with yield component traits in rice.


Assuntos
Grão Comestível/fisiologia , Ferro/metabolismo , Desequilíbrio de Ligação , Oryza/genética , Zinco/metabolismo , Grão Comestível/genética , Variação Genética , Nutrientes/metabolismo , Melhoramento Vegetal , Locos de Características Quantitativas
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