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1.
Nanotechnology ; 35(45)2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39127053

RESUMO

In pursuing advanced neuromorphic applications, this study introduces the successful engineering of a flexible electronic synapse based on WO3-x, structured as W/WO3-x/Pt/Muscovite-Mica. This artificial synapse is designed to emulate crucial learning behaviors fundamental to in-memory computing. We systematically explore synaptic plasticity dynamics by implementing pulse measurements capturing potentiation and depression traits akin to biological synapses under flat and different bending conditions, thereby highlighting its potential suitability for flexible electronic applications. The findings demonstrate that the memristor accurately replicates essential properties of biological synapses, including short-term plasticity (STP), long-term plasticity (LTP), and the intriguing transition from STP to LTP. Furthermore, other variables are investigated, such as paired-pulse facilitation, spike rate-dependent plasticity, spike time-dependent plasticity, pulse duration-dependent plasticity, and pulse amplitude-dependent plasticity. Utilizing data from flat and differently bent synapses, neural network simulations for pattern recognition tasks using the Modified National Institute of Standards and Technology dataset reveal a high recognition accuracy of ∼95% with a fast learning speed that requires only 15 epochs to reach saturation.


Assuntos
Redes Neurais de Computação , Plasticidade Neuronal , Óxidos , Tungstênio , Tungstênio/química , Plasticidade Neuronal/fisiologia , Óxidos/química , Sinapses Elétricas/fisiologia , Titânio/química , Aprendizagem , Sinapses/fisiologia
2.
Cureus ; 15(10): e46467, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37927676

RESUMO

Background In this study, we aimed to evaluate optical coherence tomography angiography (OCTA) parameters among Indian patients affected with central serous chorioretinopathy (CSCR). Methodology A cross-sectional study on Indian patients having unilateral or bilateral affection with CSCR was conducted at the Department of Ophthalmology, Guru Nanak Eye Centre, and Maulana Azad Medical College, New Delhi. A history of ocular symptoms such as a diminution of vision, metamorphopsia, decreased contrast sensitivity (CS), and defective color vision (CV) and their duration were obtained. A detailed ocular examination for best-corrected visual acuity (BCVA), intraocular pressure (IOP), CV, and CS was done. Following this, fundus fluorescein angiography (FFA) and indocyanine green angiography (ICGA) were performed. OCT was done for central foveal thickness (CFT), subfoveal choroidal thickness (SFCT), neurosensory detachment (NSD), pigment epithelial detachment (PED), and choroidal neovascular membranes (CNVMs). The OCTA imaging was done to examine the foveal avascular zone (FAZ) size, perimeter and circularity, vessel density (VD), and features such as enlarged/distorted FAZ, dark areas, dark spots, abnormal vessels, and choriocapillaris island (CCI) in the retino-choroidal layers. We compared the OCTA features of affected eyes with those of fellow eyes. Results The study involved 52 eyes of 40 CSCR patients, including 32 (80%) males and eight (20%) females with a mean age of 39.3 ± 6.1 (24-49) years. Of the 40 patients, 12 (30%) had a bilateral involvement. The mean CFT was 300.3 ± 158.4 µ, and the SFCT was 258.5 ± 60.4 µ. The mean distance BCVA was the logarithm of the minimum angle of resolution (logMAR) 0.58 ± 0.32. The OCTA showed features such as enlarged/distorted FAZ (36.53% eyes), dark areas (NSD/PED) (84.61% eyes), dark spots (PED) (5.76% eyes), abnormal vessels (dilated vessels/CNVM) (96.15% eyes), and CCI (17.30% eyes). The mean FAZ area, perimeter, and circularity were 0.40 ± 0.71 mm2, 41.8 ± 280.0 mm, and 0.48 ± 0.12, respectively. The VD in the superficial capillary plexus (SCP) was 25.4 ± 14.1, deep capillary plexus (DCP) 15.0 ± 11.5, outer retina (OR) 5.9 ± 6.8, outer retinal choriocapillaris (ORCC) 33.7 ± 16.9, choriocapillaris 29.7 ± 17.5, and choroid 29.9 ± 17.5. The fellow eyes showed a mean FAZ area, perimeter, and circularity of 0.34 ± 0.23 mm2, 76.8 ± 391.2 mm, and 0.47 ± 0.11, respectively, while VD of SCP was 25.9 ± 13.6, DCP 16.5 ± 11.7, OR 14.3 ± 14.9, ORCC 38.0 ± 16.5, choriocapillaris 36.3 ± 17.7, and choroid 35.5 ± 19.2. Conclusions The CSCR eyes had a thicker fovea and sub-foveal choroid (SFC). The FAZ area of affected eyes was larger, while the perimeter was smaller than that in the fellow eye. In the affected eye, the VD in all the retino-choroidal layers was lower, although it was significantly reduced in OR whole (p = 0.006) and foveal choroid (p = 0.022).

3.
Reprod Sci ; 30(12): 3443-3455, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37418220

RESUMO

Uterine fibroid is a common gynecological disorder that affects women of reproductive age and has emerged as a major public health concern. The symptoms have a negative influence on both their physical health and quality of life. The cost of treatment has a significant impact on the disease's burden. Even though its origin is uncertain, estrogen is thought to be a key player in fibroid pathophysiology. Many theories, including those based on genetic and environmental factors, explain what causes hyper-estrogenic condition in fibroid patients. One such possibility that is currently being explored is the hypothesis that an altered gut microbiome can contribute to the development of diseases characterized by estrogen dominance. Gut dysbiosis is often a "hot area" in the health sciences. According to a recent study, uterine fibroid patients have altered gut microbiome. A variety of risk factors influence both fibroid development and gut homeostasis. Diet, lifestyle, physical activity, and environmental contaminants have an impact on estrogen and the gut flora. A better understanding of uterine fibroids' pathophysiology is required to develop effective preventative and treatment options. A few ways by which the gut microbiota contributes to UF include estrogen, impaired immune function, inflammation, and altered gut metabolites. Therefore, in the future, while treating fibroid patients, various strategies to deal with changes in the gut flora may be advantageous. For developing suggestions for clinical diagnosis and therapy, we reviewed the literature on the relationship between uterine fibroids and the gut microbiota.


Assuntos
Microbioma Gastrointestinal , Leiomioma , Neoplasias Uterinas , Humanos , Feminino , Neoplasias Uterinas/tratamento farmacológico , Qualidade de Vida , Leiomioma/tratamento farmacológico , Estrogênios/uso terapêutico
4.
Cureus ; 15(5): e39633, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37388592

RESUMO

AIM: We aim to find an association between neovascularization (NVn) and optical coherence tomography angiography (OCTA) parameters in proliferative diabetic retinopathy (PDR). METHODS: In a prospective study, 41 subjects including 28 (68%) males and 13 (32%) females having PDR were examined for neovascularization disc (NVD) and neovascularization elsewhere (NVE) clinically and with fundus fluorescein angiography (FFA). A total of 79 eyes were found to be involved. We examined OCTA parameters including foveal avascular zone (FAZ) size, perimeter and circularity, and vessel density (VD) in the superficial capillary plexus (SCP), deep capillary plexus (DCP), outer retina (OR), outer retinal chorio-capillaries (ORCC), chorio-capillaries (CC), and choroid (C) in these subjects. RESULTS:  In eyes with NVD, the central foveal thickness (CFT) (p=0.83) and sub-foveal choroidal thickness (SFCT) (p=0.08) were higher, the FAZ area was significantly larger (p=0.005), and the VD was lower in all retino-choroidal layers. However, it was significantly lower in SCP foveal (p=0.005) and ORCC foveal (p=0.05) than in eyes not having NVD. For NVE, the CFT (p=0.03) and SFCT (p=0.01) were more in affected eyes. The eyes without NVE had a better circularity index (p=0.07) and the highest VD in OR slab (p=0.02) than those eyes that had NVE < ½ disc area (DA) and NVE > ½ DA. On comparing eyes without NVE, NVE < ½ DA, and NVE > ½ DA, the latest had the highest VD in SCP (p=0.59) and lowest VD in DCP (p=0.43) and OR (p=0.02). The VD in ORCC, CC, and choroid was highest in the no NVE group, followed by the NVE > ½ DA and NVE < ½ DA groups in that order. The subjects having vitreous hemorrhage (VH) and intra-retinal microvascular abnormalities (IRMA) had higher values for CFT and SFCT than eyes without these. CONCLUSIONS:  An increased CFT and SFCT are associated with the appearance of NVD, NVE, VH, and IRMA. The presence of NVD, VH, and IRMA is associated with a larger FAZ area, while that of IRMA and NVE is associated with reduced FAZ circularity. Eyes with NVD, VH, and IRMA had lesser VD in all the retino-choroidal layers. Eyes with NVE > ½ DA had the highest VD in SCP and lowest in DCP and OR; this pattern of VD foretells severer affection in NVE. IRMA was associated with a larger FAZ area, larger FAZ perimeter, and lesser circularity, indicating the presence of central ischemia.

5.
MethodsX ; 10: 101992, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36845368

RESUMO

Water Conservation is the need of the hour and attitudes towards conserving the resources is what is sure to become a priority in the coming years. In order to understand what could influence the change in attitude and thereby bring about a change of behavior, we first need to shift our attention from understanding the water crisis to understanding the existing attitude of the society towards a water crisis. In the current work we address the current attitude towards water conservation by providing baseline data about Indians' attitudes and behavior/behavioral intentions in conserving water. We introduce a scale constructed to test the Attitude towards water conservation in India. The scale consists of 20 items divided into 5 sub-scales. We conducted a nationwide survey on 430 Participants and their responses were checked for reliability. The internal consistency values of all 5 scales were ranged between 0.68 and 0.73 •Out of the 15 questions from Attitude towards water conservation from Dolnicar, S., & Hurlimann, A. (2010) 1 question was changed to suit Indian context•5 questions were added to show Perceived Moral Obligation, Behavioral Intensions and Perceived Water Rights.

6.
Cureus ; 15(1): e33548, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36779162

RESUMO

INTRODUCTION: This study aims to evaluate retinochoroidal optical coherence tomography angiography (OCTA) parameters in patients recovered from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). METHODS: This study was an observational study that included 80 subjects being discharged after having negative reports on the reverse transcription-polymerase chain reaction (RT-PCR) test for SARS-CoV-2 to evaluate OCTA parameters of the retina. The subjects underwent an ophthalmic evaluation that included best-corrected visual acuity (BCVA), intraocular pressure (IOP), color vision (CV), contrast sensitivity (CS), and optical coherence tomography (OCT) parameters. OCTA was done for all patients and was evaluated for foveal avascular zone (FAZ) area, perimeter, and circularity index, and vessel density (VD) in superficial capillary plexus (SCP), deep capillary plexus (DCP), outer retina (OR), outer retina chorio-capillaries (ORCC), chorio-capillaries (CC), and choroid (C) using 3 x 3 mm scans. The OCTA parameters were compared with normative data of the Indian population for various parameters in question. RESULTS: The subjects included 54/80 (67.5%) males and 26/80 (32.5%) females having a mean age of 52.40 ± 15.71 (18-60) years. The systemic evaluation revealed 38.75% of subjects had hypertension, 30% had diabetes, 20% had kidney disease, 5% had tuberculosis, and 3.75% had coronary artery disease. The mean distance BCVA was logarithm of the minimum angle of resolution (LogMAR) (1.17 ± 0.22), mean IOP was 17.0 ± 4.0 mmHg, mean CS was 2.13 ± 0.36, 50.62% of subjects had normal CV on Farnsworth test while 47% had tritanopia, and none of the subjects had red-green CV defect on Ishihara plates. The OCT scan was normal in 90% of eyes while the posterior vitreous detachment was seen in 4% of eyes, broad vitreomacular adhesion in 2.5% of eyes, and the globally adherent epiretinal membrane was seen in 2.5% of eyes. The mean central macular thickness (CMT) measured 245.14 ± 28.41 micrometers. The mean FAZ area measured 0.37 ± 0.15 mm2, the perimeter was 3.28 ± 1.08 mm, and the circularity index measured 0.41 ± 0.10. The average VD in SCP measured 16.06 ± 12.29, in DCP measured 9.11 ± 8.75, in OR measured 6.38 ± 7.37, in ORCC measured 42.53 ± 12.46, in CC measured 25.83 ± 16.31, and in C measured 25.52 ± 17.49. The VD in coronavirus disease 2019 (COVID-19) subjects was significantly lesser than that in the healthy Indian population in all layers except ORCC. CONCLUSIONS: The SARS-CoV-2 recovered subjects have a reduced VD in retinochoroidal layers from COVID-19, an underlying systemic disease, or both. The CS values fall within normal limits. Several subjects show tritanopia on the Farnsworth test but no red-green CV defect on Ishihara plates.

7.
Phys Rev E ; 106(4-1): 044129, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36397596

RESUMO

Absolute negative mobility, where particles move opposite to the direction as governed by the external load, is an anomalous transport property of a Brownian ratchet and has technological implications in mass separation and bioanalytical applications. We numerically investigated here the effect of roughness in symmetric periodic potential on the negative mobility of a driven inertial Brownian ratchet in the presence of an external load. We show that the microscopic spatial heterogeneity of the potential can generate negative mobility which would not otherwise be possible under smooth potential in the concerned parameter space. We determined the optimal condition in terms of parameter space for such anomalous behavior. Our calculations indicate that the shift of balance towards the negative velocity phase in the temporal oscillations of velocity and weakly chaotic dynamics are responsible factors for roughness-induced negative mobility. These calculations highlight a constructive role of roughness in the anomalous transport properties of Brownian ratchet.

8.
Cureus ; 14(8): e27669, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36072178

RESUMO

OBJECTIVE: The foveal avascular zone (FAZ) is the round capillary-free zone within the macula and is supplied only by a single-layered parafoveal capillary arcade. This study aimed to evaluate the quantitative FAZ and retino-choroidal vessel density (VD) using optical coherence tomography angiography (OCTA) in a healthy Indian population. METHODS: This was a cross-sectional observational study that was conducted for evaluating the quantitative FAZ and retino-choroidal VD of 200 eyes of 100 healthy Indian subjects, including 62 males and 38 females (age range 17-50 years) having the best-corrected visual acuity (BCVA) of logMAR 0 (20/20; 6/6) and spherical equivalent refractive error of not more than 1 D. The subjects were examined using OCTA automated software on spectral-domain OCT (SD-OCT; Nidek RS 3000 Advance 2; Nidek, Inc., Fremont, CA) on a 3 x 3 mm OCTA macular scan centred on the fovea. The FAZ size, perimeter and circularity index, VD in superficial, deep, and outer retina (OR), outer retinal chorio-capillaries (ORCC), chorio-capillaries (CC) and choroid (C) were analysed in the circular and quadrant-segmented zones. A correlation was found between the FAZ size, perimeter and circularity, and VD in retino-choroidal layers, and between BCVA, age, central foveal thickness (CFT) and sub-foveal choroidal thickness (SFCT), and OCTA parameters. RESULTS: The FAZ and surrounding vascular arcades were intact in all eyes, showing either a vertical or horizontal oval-shaped symmetrical formation without gaps, holes or interruption of the capillary network. The mean value of CFT was 237.5±26.0 microns and SFCT was 269.6±53.0 microns. The mean FAZ area was 0.42±0.23 mm2, FAZ perimeter was 3.3±1.0 mm and FAZ circularity index was 0.46±0.1. The mean VD in superficial capillary plexus (SCP) was 23.87±10.66, in deep capillary plexus (DCP) was 16.03±9.90, in OR was 13.22± 12.27, in ORCC was 39.74±14.32, in CC was 37.02±16.43 and in choroid was 37.43±16.76. The increasing order of VD in different retino-choroidal layers was OR

9.
J Ayurveda Integr Med ; 13(3): 100596, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35693195

RESUMO

Background: COVID-19 outbreak is considered to be a major public health concern as it has a negative impact on the patient's psychological health. In addition, patients under home isolation might be more panic and in stress. In this study, we examined the effect of Bhramari Pranayama (Bhr.P) intervention on patients' psychological distress during home isolation. Methods: Ninety-two asymptomatic COVID-19 patients were recruited from the host hospital and willing patients who satisfied the inclusion criteria (n = 42) were selected for the study. The patients were given Bhr.P intervention (20 min) through online for 15 days. Participants were assessed with Depression Anxiety and Stress Scale-21 (DASS-21), Pittsburgh Sleep Quality Index (PSQI), and Quality of life (WHOQOL-BREF) at baseline and post-intervention. Results: Bhr.P practice has shown a significant (P < 0.05) reduction in DASS-21 score of depression, anxiety and stress. In addition, the patients stated significant improvement in quality of sleep (PSQI; p < 0.05) and quality of life (WHOQOL-BREF; p < 0.05) after the intervention. Conclusion: Our findings indicate that Bhr.P intervention had a positive impact on psychological health as well as quality of sleep among the COVID-19 patients during home isolation. However, it needs to be confirmed by multi-site randomized controlled trials.Clinical trial registration: CTRI/2021/04/032845.

10.
Phys Rev E ; 104(2-1): 024103, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34525624

RESUMO

We study the effects of roughness in the asymmetric periodic potential on the transport and diffusion of an inertial Brownian particle driven by a time-periodic force in a Gaussian environment. We find that moderate roughness leads to the loss of transient anomalous diffusion, and it helps to establish normal diffusion in the weak noise limit. We uncover a contrasting effect of roughness on the transport of particles in the weak and moderate to large noise limit. In the weak noise limit, small amplitude roughness results in the increase of directed transport, whereas in the moderate to large noise limit, roughness hinders transport. The deterministic dynamics of the system reveals that the purely periodic system under smooth potential transits into a chaotic system due to the moderate roughness in the potential. Therefore our calculations demonstrate the constructive role of roughness in the transport of particles in the inertial regime.

16.
Phys Rev E ; 99(2-1): 022103, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30934250

RESUMO

In this study we used a nonequilibrium simulation method to investigate the temperature dependent divergence of thermal conductivity in a one-dimensional momentum conserving system with an asymmetric double well nearest-neighbor interaction potential. We show that across all temperatures thermal conductivity exhibits power-law divergence with the chain length and the value of the divergence exponent (α) depends on the temperature of the system. At low and high temperatures α reaches close to ∼0.5 and ∼0.33, respectively. Whereas in the intermediate temperature the divergence of thermal conductivity with the chain length saturates with α∼0.07. Subsequent analysis showed that the estimated value of α in the intermediate temperature may not have reached its thermodynamic limit. Further calculations of local α revealed that its approach towards the thermodynamic limit is crucially dependent on the temperature of the system. At low and high temperatures local α reaches its thermodynamic limits in shorter chain lengths. On the contrary, in the case of intermediate temperature its progress towards the asymptotic limit is nonmonotonic.

19.
Mutat Res ; 726(2): 136-45, 2011 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-21933721

RESUMO

The radioprotective and anticlastogenic potential of a phenol derivative monoterpene thymol(TOH), against whole-body gamma radiation was studied in Swiss albino mice. Acute toxicity of TOH, with an LD(50(14)) of 1134.03mg/kgbwt., was observed when administered intra-peritoneally (i.p.). The radioprotective potential of TOH was evaluated using the optimal dose of 10mg/kgbwt. TOH, which increased the LD(50/30) by 2.17Gy and resulted in a dose reduction factor (DRF) of 1.25. A significant (p<0.01) reduction in micronucleated, polychromatic erythrocytes (PCE), normochromatic erythrocytes (NCE), and an increased PCE/NCE ratio was also observed after administration of 10mg/kg.b.wt. TOH prior to gamma radiation, indicating its antigenotoxic effect. TOH pre-treatment significantly (p<0.01) elevated reduced glutathione, glutathione-S-transferase, catalase, and superoxide dismutase levels and decreased lipid peroxidation levels in mouse liver homogenates at 24 and 48h after exposure to 4.5Gy of radiation. Further, TOH treatment before exposure to 7.5Gy of gamma radiation resulted in a significant (p<0.01) increase in hematological parameters at various post-treatment time points, with increased numbers of endogenous spleen colonies as well. The histological observations indicated a decline in villus heights and crypt numbers in mouse jejunum and were accompanied by a significant decrease in bone marrow nucleated cells in the irradiated group, which was almost normalized by pre-treatment with TOH. Our study clearly documents the antioxidant, anticlastogenic and radioprotective potentials of TOH, which may be attributed to several possible mechanisms, such as normalization of intracellular antioxidant levels and free radical scavenging activities by TOH.


Assuntos
Antimutagênicos/farmacologia , Antioxidantes/farmacologia , Protetores contra Radiação/farmacologia , Timol/farmacologia , Animais , Células Sanguíneas/efeitos dos fármacos , Células da Medula Óssea/efeitos dos fármacos , Raios gama , Mucosa Intestinal/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Camundongos , Micronúcleos com Defeito Cromossômico , Timol/toxicidade
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