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1.
J Chem Phys ; 161(14)2024 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-39387414

RESUMEN

The transport of particles through channels holds immense significance in physics, chemistry, and biological sciences. For instance, the motion of solutes through biological membranes is facilitated by specialized proteins that create water-filled channels. Valuable insights can be obtained by studying the transition paths of particles through a channel and gathering information on their lifetimes inside the channel as well as their exit probabilities. In a similar vein, we consider a one-dimensional model of channel-facilitated transport where a diffusive particle is subject to attractive interactions with the walls of the channel. We study the statistics of conditional and unconditional escape times in the presence of resetting-an intermittent dynamics that brings the particle back to its initial coordinate stochastically. We determine analytically the physical conditions under which such a resetting mechanism becomes beneficial for the faster escape of the particles from the channel, thus enhancing transport. Our theory has been verified with the aid of Brownian dynamics simulations for various interaction strengths and extents. The overall results presented herein highlight the scope of resetting-based strategies to be universally promising for complex transport processes of single or long molecules through biological membranes.

2.
PLOS Digit Health ; 3(9): e0000421, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39259731

RESUMEN

Mobile health applications called Digital Adherence Technologies (DATs), are increasingly used for improving treatment adherence among Tuberculosis patients to attain cure, and/or other chronic diseases requiring long-term and complex medication regimens. These DATs are found to be useful in resource-limited settings because of their cost efficiency in reaching out to vulnerable groups (providing pill and clinic visit reminders, relevant health information, and motivational messages) or those staying in remote or rural areas. Despite their growing ubiquity, there is very limited evidence on how DATs improve healthcare outcomes. We analyzed the uptake of DATs in an urban setting (DS-DOST, powered by Connect for LifeTM, Johnson & Johnson) among different patient groups accessing TB services in New Delhi, India, and subsequently assessed its impact in improving patient engagement and treatment outcomes. This study aims to understand the uptake patterns of a digital adherence technology and its impact in improving follow-ups and treatment outcomes among TB patients. Propensity choice modelling was used to create balanced treated and untreated patient datasets, before applying simple ordinary least square and logistic regression methods to estimate the causal impact of the intervention on the number of follow-ups made with the patient and treatment outcomes. After controlling for potential confounders, it was found that patients who installed and utilized DS-DOST application received an average of 6.4 (95% C.I. [5.32 to 7.557]) additional follow-ups, relative to those who did not utilize the application. This translates to a 58% increase. They also had a 245% higher likelihood of treatment success (Odds ratio: 3.458; 95% C.I. [1.709 to 6.996]).

3.
J Perinatol ; 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39227477

RESUMEN

OBJECTIVE: To determine agreement between neonatal cerebrospinal fluid (CSF) glucose measured by standard laboratory method versus blood gas analyzers (BGA) and glucometers. STUDY DESIGN: This prospective, observational, cross-sectional study was conducted in a level III neonatal unit on 97 neonates undergoing lumbar puncture. Agreement was estimated by Lin's coefficient of concordance and Bland-Altman plot. RESULTS: Lin's coefficient of concordance between the CSF laboratory and BGA glucose values was higher than that between CSF laboratory and glucometer glucose {P value < 0.001}. Bland-Altman plot of CSF glucose values by laboratory and BGA methods showed a bias of -0.137 mmol/l. The plot of laboratory versus glucometer methods showed a bias of -0.863 mmol/l. A linear regression equation to predict laboratory CSF glucose from BGA values and glucometer values had an R2 of 0.975 and 0.971 respectively. CONCLUSIONS: CSF glucose measured by blood gas analyzers may be used as a point-of-care test among neonates. TRIAL REGISTRATION: Not applicable.

4.
Asian J Neurosurg ; 19(3): 386-394, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39205884

RESUMEN

Objectives Neurosurgical patients often receive 0.9% normal saline (NS) during the perioperative period. Theoretically, a balanced salt solution (BSS) is better than 0.9% saline. We compared the effects of two different fluids on acid-base balance, renal function, and neurological outcome in patients who underwent clipping following subarachnoid hemorrhage from a ruptured intracranial aneurysm. Materials and Methods Patients in group NS ( n = 30) received 0.9% saline and group BSS ( N = 30) received BSS (Plasmalyte-A) in the perioperative period for 48 hours. Comparison of arterial pH, bicarbonate, and base deficit measured preoperatively, intraoperatively (first and second hour), and postoperatively (at 24 and 48 hours) was the primary outcome of the study. The secondary outcome compared serum electrolytes, renal function tests, urine neutrophil gelatinase-associated lipocalin (NGAL), serum cystatin C, and the neurological outcome using modified Rankin score (MRS) at discharge, 1, and 3 months. Results In group NS, significantly low pH at 1-hour intraoperative period was seen compared with group BSS (7.37 ± 0.06 vs. 7.40 ± 0.05, p = 0.024). The bicarbonate level in group NS was significantly lower and the base deficit was higher at second intraoperative hour (bicarbonate: 17.49 vs. 21.99 mEq/L, p = 0.001; base deficit: 6.41 mmol/L vs. 1.89 mmol/L, p = 0.003) and at 24 hours post-surgery (bicarbonate: 20.38 vs. 21.96 mEq/L, p = 0.012; base deficit: 3.56 mmol/L vs. 2.12 mmol/L, p = 0.034)). Serum creatinine was higher in group NS at 24 hours (0.66 vs. 0.52 mg/dL, p = 0.013) and 48 hours (0.62 vs. 0.53 mg/dL, p = 0.047). Serum urea, electrolytes, cystatin, urine NGAL, and MRS were comparable. Conclusion In neurosurgical patients undergoing clipping for ruptured intracranial aneurysm, using a BSS during the perioperative period is associated with a better acid-base and renal profile. However, the biomarkers of kidney injury and long-term outcomes were comparable.

5.
Front Oral Health ; 5: 1426507, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39157206

RESUMEN

Oral cancer is the 6th most common type of cancer worldwide, and oral squamous cell carcinoma (OSCC) accounts for >90% of oral cancers. It is a major health problem, particularly in low- and middle-income countries (LMICs), due to both its high incidence and significant mortality and morbidity. Despite being a global burden, and even with the significant advancement in the management of OSCC, the overall outcome of the disease is still abysmal. With the advent of time, advanced diagnostic and treatment approaches have come into practice, but the burden of the disease has not improved significantly. Major reasons attributed to the poor outcome are delay in diagnosis, locoregional recurrence and resistance to the currently available treatment regimen. In this review, we have highlighted the existing challenges in the diagnosis and have emphasized the advancements in minimally invasive biomarkers. Additionally, the importance of collaborative multidimensional approaches involving clinicians and researchers has been discussed, as well as the need to redefine and establish better utility and management of existing diagnostic and treatment protocols along with the minimally invasive/non-invasive biomarkers.

6.
OMICS ; 28(5): 234-245, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38717843

RESUMEN

Cerebral vasospasm (CV) is a significant complication following aneurysmal subarachnoid hemorrhage (aSAH), and lacks a comprehensive molecular understanding. Given the temporal trajectory of intracranial aneurysm (IA) formation, its rupture, and development of CV, altered gene expression might be a molecular substrate that runs through these clinical events, influencing both disease inception and progression. Utilizing RNA-Seq, we analyzed tissue samples from ruptured IAs with and without vasospasm to identify the dysregulated genes. In addition, temporal gene expression analysis was conducted. We identified seven dysregulated genes in patients with ruptured IA with vasospasm when compared with those without vasospasm. We found 192 common genes when the samples of each clinical subset of patients with IA, that is, unruptured aneurysm, ruptured aneurysm without vasospasm, and ruptured aneurysm with vasospasm, were compared with control samples. Among these common genes, TNFSF13B, PLAUR, OSM, and LAMB3 displayed temporal expression (progressive increase) with the pathological progression of disease that is formation of aneurysm, its rupture, and consequently the development of vasospasm. We validated the temporal gene expression pattern of OSM at both the transcript and protein levels and OSM emerges as a crucial gene implicated in the pathological progression of disease. In addition, RSAD2 and ATP1A2 appear to be pivotal genes for CV development. To the best of our knowledge, this is the first study to compare the transcriptome of aneurysmal tissue samples of aSAH patients with and without CV. The findings collectively provide new insights on the molecular basis of IA and CV and new leads for translational research.


Asunto(s)
Perfilación de la Expresión Génica , Aneurisma Intracraneal , Transcriptoma , Vasoespasmo Intracraneal , Humanos , Vasoespasmo Intracraneal/genética , Vasoespasmo Intracraneal/metabolismo , Aneurisma Intracraneal/genética , Aneurisma Intracraneal/metabolismo , Aneurisma Intracraneal/complicaciones , Transcriptoma/genética , Perfilación de la Expresión Génica/métodos , Masculino , Femenino , Hemorragia Subaracnoidea/genética , Hemorragia Subaracnoidea/complicaciones , Hemorragia Subaracnoidea/metabolismo , Regulación de la Expresión Génica , Persona de Mediana Edad , Aneurisma Roto/genética , Aneurisma Roto/complicaciones
7.
Lung India ; 41(2): 84-92, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38700400

RESUMEN

BACKGROUND: Mycobacterium w (Mw), an immunomodulator, resulted in better clinical status in severe coronavirus infectious disease 19 (COVID-19) but no survival benefit in a previous study. Herein, we investigate whether Mw could improve clinical outcomes and survival in COVID-19. MATERIALS AND METHODS: In a multicentric, randomized, double-blind, parallel-group, placebo-controlled trial, we randomized hospitalized subjects with severe COVID-19 to receive either 0.3 mL/day of Mw intradermally or a matching placebo for three consecutive days. The primary outcome was 28-day mortality. The co-primary outcome was the distribution of clinical status assessed on a seven-point ordinal scale ranging from discharged (category 1) to death (category 7) on study days 14, 21, and 28. The key secondary outcomes were the change in sequential organ failure assessment (SOFA) score on days 7 and 14 compared to the baseline, treatment-emergent adverse events, and others. RESULTS: We included 273 subjects (136 Mw, 137 placebo). The use of Mw did not improve 28-day survival (Mw vs. placebo, 18 [13.2%] vs. 12 [8.8%], P = 0.259) or the clinical status on days 14 (odds ratio [OR], 1.33; 95% confidence intervals [CI], 0.79-2.3), 21 (OR, 1.49; 95% CI, 0.83-2.7) or 28 (OR, 1.49; 95% CI, 0.79-2.8) between the two study arms. There was no difference in the delta SOFA score or other secondary outcomes between the two groups. We observed higher injection site reactions with Mw. CONCLUSION: Mw did not reduce 28-day mortality or improve clinical status on days 14, 21 and 28 compared to placebo in patients with severe COVID-19. [Trial identifier: CTRI/2020/04/024846].

8.
Eur Phys J E Soft Matter ; 47(5): 34, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38782771

RESUMEN

We present a scheme for producing tunable active dynamics in a self-propelled robotic device. The robot moves using the differential drive mechanism where two wheels can vary their instantaneous velocities independently. These velocities are calculated by equating robot's equations of motion in two dimensions with well-established active particle models and encoded into the robot's microcontroller. We demonstrate that the robot can depict active Brownian, run and tumble, and Brownian dynamics with a wide range of parameters. The resulting motion analyzed using particle tracking shows excellent agreement with the theoretically predicted trajectories. Later, we show that its motion can be switched between different dynamics using light intensity as an external parameter. Intriguingly, we demonstrate that the robot can efficiently navigate through many obstacles by performing stochastic reorientations driven by the gradient in light intensity towards a desired location, namely the target. This work opens an avenue for designing tunable active systems with the potential of revealing the physics of active matter and its application for bio- and nature-inspired robotics.

9.
Mycoses ; 67(5): e13746, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38767275

RESUMEN

BACKGROUND: Post-tuberculosis lung abnormality (PTLA) is the most common risk factor for chronic pulmonary aspergillosis (CPA), and 14%-25% of the subjects with PTLA develop CPA. The pathogenesis and the host immune response in subjects with PTLA who develop CPA need to be better understood. METHODS: We prospectively compared the innate and adaptive immune responses mounted by patients of PTLA with or without CPA (controls). We studied the neutrophil oxidative burst (by dihydrorhodamine 123 test), classic (serum C3 and C4 levels) and alternative (mannose-binding lectin [MBL] protein levels) complement pathway, serum immunoglobulins (IgG, IgM and IgA), B and T lymphocytes and their subsets in subjects with PTLA with or without CPA. RESULTS: We included 111 subjects (58 CPA and 53 controls) in the current study. The mean ± SD age of the study population was 42.6 ± 15.7 years. The cases and controls were matched for age, gender distribution and body weight. Subjects with CPA had impaired neutrophil oxidative burst, lower memory T lymphocytes and impaired Th-1 immune response (lower Th-1 lymphocytes) than controls. We found no significant difference between the two groups in the serum complement levels, MBL levels, B-cell subsets and other T lymphocyte subsets. CONCLUSION: Subjects with CPA secondary to PTLA have impaired neutrophil oxidative burst and a lower Th-1 response than controls.


Asunto(s)
Inmunidad Adaptativa , Inmunidad Innata , Aspergilosis Pulmonar , Tuberculosis Pulmonar , Humanos , Femenino , Masculino , Adulto , Persona de Mediana Edad , Tuberculosis Pulmonar/inmunología , Tuberculosis Pulmonar/complicaciones , Estudios Prospectivos , Aspergilosis Pulmonar/inmunología , Aspergilosis Pulmonar/complicaciones , Neutrófilos/inmunología , Pulmón/inmunología , Estallido Respiratorio , Adulto Joven
10.
J Chem Phys ; 160(13)2024 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-38563303

RESUMEN

Thermal activation of a particle from a deep potential trap follows the Arrhenius law. Recently, this result has been generalized for interacting diffusive particles in the trap, revealing two universality classes-the Arrhenius class and the excluded volume class. The result was demonstrated with the aid of numerical analysis. Here, we present a perturbative hydrodynamic approach to analytically validate the existence and range of validity for the two universality classes.

11.
Nat Commun ; 15(1): 3392, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38649379

RESUMEN

Brain-like energy-efficient computing has remained elusive for neuromorphic (NM) circuits and hardware platform implementations despite decades of research. In this work we reveal the opportunity to significantly improve the energy efficiency of digital neuromorphic hardware by introducing NM circuits employing two-dimensional (2D) transition metal dichalcogenide (TMD) layered channel material-based tunnel-field-effect transistors (TFETs). Our novel leaky-integrate-fire (LIF) based digital NM circuit along with its Hebbian learning circuitry operates at a wide range of supply voltages, frequencies, and activity factors, enabling two orders of magnitude higher energy-efficient computing that is difficult to achieve with conventional material and/or device platforms, specifically the silicon-based 7 nm low-standby-power FinFET technology. Our innovative 2D-TFET based NM circuit paves the way toward brain-like energy-efficient computing that can unleash major transformations in future AI and data analytics platforms.

12.
Phys Rev E ; 109(3): L032101, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38632768

RESUMEN

Finding the mean time it takes for a particle to escape from a metastable state due to thermal fluctuations is a fundamental problem in physics, chemistry, and biology. Here, we consider the escape rate of interacting diffusive particles, from a deep potential trap within the framework of the macroscopic fluctuation theory-a nonequilibrium hydrodynamic theory. For systems without excluded volume, our investigation reveals adherence to the well-established Arrhenius law. However, in the presence of excluded volume, a universality class emerges, fundamentally altering the escape rate. Remarkably, the modified escape rate within this universality class is independent of the interactions at play. The universality class, demonstrating the importance of excluded volume effects, may bring insights to the interpretation of escape processes in the realm of chemical physics.

13.
Front Oncol ; 14: 1269211, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38469233

RESUMEN

Purpose: Isolating circulating tumour cells (CTCs) from the blood is challenging due to their low abundance and heterogeneity. Limitations of conventional CTC detection methods highlight the need for improved strategies to detect and isolate CTCs. Currently, the Food and Drug Administration (FDA)-approved CellSearch™ and other RUO techniques are not available in India. Therefore, we wanted to develop a flexible CTC detection/isolation technique that addresses the limitation(s) of currently available techniques and is suitable for various downstream applications. Methods: We developed a novel, efficient, user-friendly CTC isolation strategy combining density gradient centrifugation and immuno-magnetic hematogenous cell depletion with fluorescence-activated cell sorting (FACS)-based positive selection using multiple CTC-specific cell-surface markers. For FACS, a stringent gating strategy was optimised to exclude debris and doublets by side scatter/forward scatter (SSC/FSC) discriminator, remove dead cells by 4',6-diamidino-2-phenylindole (DAPI) staining, and eliminate non-specific fluorescence using a "dump" channel. APC-labelled anti-CD45mAB was used to gate remaining hematogenous cells, while multiple epithelial markers (EpCAM, EGFR, and Pan-Cytokeratin) and an epithelial-mesenchymal transition (EMT) marker (Vimentin) labelled with fluorescein isothiocyanate (FITC) were used to sort cancer cells. The technique was initially developed by spiking Cal 27 cancer cells into the blood of healthy donors and then validated in 95 biopsy-proven oral squamous cell carcinoma (OSCC) patients. CTCs isolated from patients were reconfirmed by Giemsa staining, immuno-staining, and whole transcriptome amplification (WTA), followed by qRT-PCR. In vitro culture and RNA sequencing (RNA-Seq) were also performed to confirm their suitability for various downstream applications. Results: The mean detection efficiency for the Cal 27 tongue cancer cells spiked in the whole blood of healthy donors was 32.82% ± 12.71%. While ~75% of our patients (71/95) had detectable CTCs, the CTC positivity was independent of the TNM staging. The isolated potential cancer cells from OSCC patients were heterogeneous in size. They expressed different CTC-specific markers in various combinations as identified by qRT-PCR after WTA in different patients. Isolated CTCs were also found to be suitable for downstream applications like short-term CTC culture and RNA-Seq. Conclusion: We developed a sensitive, specific, flexible, and affordable CTC detection/isolation technique, which is scalable to larger patient cohorts, provides a snapshot of CTC heterogeneity, isolates live CTCs ready for downstream molecular analysis, and, most importantly, is suitable for developing countries.

14.
BMJ Open ; 14(3): e069304, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38508628

RESUMEN

OBJECTIVES: To estimate the potential impact of expanding services offered by the Joint Effort for Elimination of Tuberculosis (JEET), the largest private sector engagement initiative for tuberculosis (TB) in India. DESIGN: We developed a mathematical model of TB transmission dynamics, coupled with a cost model. SETTING: Ahmedabad and New Delhi, two cities with contrasting levels of JEET coverage. PARTICIPANTS: Estimated patients with TB in Ahmedabad and New Delhi. INTERVENTIONS: We investigated the epidemiological impact of expanding three different public-private support agency (PPSA) services: provider recruitment, uptake of cartridge-based nucleic acid amplification tests and uptake of adherence support mechanisms (specifically government supplied fixed-dose combination drugs), all compared with a continuation of current TB services. RESULTS: Our results suggest that in Delhi, increasing the use of adherence support mechanisms among private providers should be prioritised, having the lowest incremental cost-per-case-averted between 2020 and 2035 of US$170 000 (US$110 000-US$310 000). Likewise in Ahmedabad, increasing provider recruitment should be prioritised, having the lowest incremental cost-per-case averted of US$18 000 (US$12 000-US$29 000). CONCLUSION: Results illustrate how intervention priorities may vary in different settings across India, depending on local conditions, and the existing degree of uptake of PPSA services. Modelling can be a useful tool for identifying these priorities for any given setting.


Asunto(s)
Sector Privado , Tuberculosis , Humanos , Sector de Atención de Salud , Tuberculosis/prevención & control , Atención a la Salud , Ciudades , India
15.
Indian Dermatol Online J ; 15(2): 252-254, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38550809

RESUMEN

Background: Nodulocystic acne is a severe type of acne that is known to improve after treatment with isotretinoin. Melnik has hypothesized a unifying concept on the mechanism of acne pathogenesis involving altered expression of Forkhead box O transcription factor (FoxO1) and role of isotretinoin in improving acne via modulating this pathway. Aim: To evaluate the pathway proposed by Melnik in acne pathogenesis by analysing the difference in the expression of FoxO1, peroxisome proliferator-activated receptor (PPARγ), and androgen receptor (AR) between acne patients and non-acne controls and the effect of treatment with isotretinoin on change in expression of these genes in acne patients. Results: The gene expression of FoxO1 was non significantly higher in acne patients as compared to controls. After treatment with isotretinoin, a significant decrease in FoxO1 expression in acne patients at mRNA (P = 0.05) level was observed. There was a significant decrease in grade 3 positivity of FoxO1 at protein level (P = 0.0009). A decrease in androgen receptor positivity (P = 0.055) at protein level was also observed. Conclusion: Reduction in FoxO1 expression appears to be an important mechanism of action of isotretinoin in acne.

16.
Front Nutr ; 11: 1312581, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38487633

RESUMEN

Introduction: Poor nutritious diet is a major risk element for non-communicable diseases (NCD), which are of considerable public health concern. Given the diverse dietary patterns in India, precise determination of nutrient consumption is crucial for disease management. The present study assessed the dietary intake of sodium, potassium, protein, and phosphorus among North Indians. Methods: This cross-sectional study included healthy adults and adults with stage 2 to 4 chronic kidney disease (CKD). We analysed sodium, protein, potassium and phosphorus intakes using one-time 24-h urinary excretion. Dietary intake was also analysed in subgroups based on sex, body mass index, blood pressure and abdominal obesity. We evaluated the performance of various equations available to estimate sodium intake using a spot urine sample with respect to the sodium excretion measured in a 24-h urine sample. Descriptive statistics was used along with t-test for statistical significance. Results: A total of 404 subjects (182 adult healthy subjects and 222 adults with CKD) with a mean age of 47.01 ± 11.46 years were studied. Mean dietary intakes of sodium, salt, potassium, protein and phosphorus were 2.94 ± 1.68 g/day, 7.42 ± 4.24 g/day, 1.43 ± 0.59 g/day, 47.67 ± 14.73 g/day and 0.86 ± 0.39 g/day, respectively. There were no differences in nutrient consumption between adults who were healthy and those with CKD. Consumption of sodium, salt, protein, potassium, and phosphorus among healthy population vs. those with CKD were 2.81 ± 1.60 vs. 3.05 ± 1.73 g/day (p = 0.152), 7.08 ± 4.04 vs. 7.70 ± 4.37 g/day (p = 0.143), 47.16 ± 14.59 vs. 48.08 ± 14.86 g/day (p = 0.532), 1.38 ± 0.59 vs. 1.48 ± 0.58 g/day (p = 0.087) and 0.86 ± 0.41 vs. 0.87 ± 0.37 g/day (p = 0.738), respectively. Men had higher consumption of these nutrients than women. Compared to non-hypertensives, hypertensive subjects had higher consumption of salt (8.23 ± 4.89 vs. 6.84 ± 3.59 g/day, p = 0.002) and potassium (1.51 ± 0.63 vs. 1.38 ± 0.55 g/day, p = 0.024), however, no difference were found in protein and phosphorus intakes. In terms of performance of equations used to estimate 24-h sodium intake from spot urinary sodium concentration against the measured 24-h urinary sodium excretion, INTERSALT 2 equation exhibited the least bias [1.08 (95% CI, -5.50 to 7.66)]. Conclusion: The study shows higher-than-recommended salt and lower-than-recommended potassium intake in the north Indian population compared to those recommended by guidelines. The dietary protein intake is below the recommended dietary allowance. These findings help the development of targeted policies for dietary modification to reduce the risk of the development and progression of CKD.

17.
Chaos ; 34(2)2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38363963

RESUMEN

Synchronization is one of the emerging collective phenomena in interacting particle systems. Its ubiquitous presence in nature, science, and technology has fascinated the scientific community over the decades. Moreover, a great deal of research has been, and is still being, devoted to understand various physical aspects of the subject. In particular, the study of interacting active particles has led to exotic phase transitions in such systems which have opened up a new research front-line. Motivated by this line of work, in this paper, we study the directional synchrony among self-propelled particles. These particles move inside a bounded region, and crucially their directions are also coupled with spatial degrees of freedom. We assume that the directional coupling between two particles is influenced by the relative spatial distance which changes over time. Furthermore, the nature of the influence is considered to be both short and long-ranged. We explore the phase transition scenario in both the cases and propose an approximation technique which enables us to analytically find the critical transition point. The results are further supported with numerical simulations. Our results have potential importance in the study of active systems like bird flocks, fish schools, and swarming robots where spatial influence plays a pertinent role.

18.
Ir J Med Sci ; 193(2): 769-775, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37528246

RESUMEN

BACKGROUND: Spinal cord injury (SCI) can result in lifelong disability. Currently, the literature suggests that biomarkers are helpful in prognosticating SCI, but there is no specific biomarker to date. This is the first study that predicted the prognosis dynamically using biomarkers. AIM: To elucidate the role of biomarkers in prognosticating acute traumatic SCI. METHODS: Blood samples were obtained from 35 patients of acute traumatic SCI at presentation, immediate post-op, and at 6 weeks. At 6 months follow-up, patients were divided into two groups, i.e, improved and non-improved based on the improvement in the ASIA grade compared to presentation. A non-parametric test was used for comparing mean NSE, MMP-2, S100-B, and NF serum levels at presentation, immediate post-op, and 6 weeks post-op follow-up between the two groups. RESULTS: There was a significant difference (p = 0.03) in the NF values at presentation between the two groups. The difference of NSE values at 6 weeks was also significant (p = 0.016) between the two groups. S-100B levels were also significantly different between both groups at presentation (p=0.016), and at the immediate post-op stage (p=0.007). MMP-2 levels neither displayed any specific trend nor any significant difference between the two groups. CONCLUSION: Higher NF values at presentation, and higher S-100B levels at presentation and immediate post-operative period correlated with poor outcome. Also, increased NSE values after surgery are indicative of no improvement. These levels can be used at various stages to predict the prognosis. However, further studies are required on this topic extensively to know the exact cut-off values of these markers to predict the prognosis accurately. CLINICAL TRIALS REGISTRY NUMBER: REF/2020/01/030616.


Asunto(s)
Metaloproteinasa 2 de la Matriz , Traumatismos de la Médula Espinal , Humanos , Subunidad beta de la Proteína de Unión al Calcio S100 , Filamentos Intermedios , Biomarcadores , Fosfopiruvato Hidratasa , Metaloproteinasas de la Matriz
19.
Adv Sci (Weinh) ; 11(4): e2307266, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38032132

RESUMEN

Triboelectrification necessitates a frictional interaction between two materials, and their contact electrification is characteristically based on the polarity variance in the triboelectric series. Utilizing this fundamental advantage of the triboelectric phenomenon, different materials can be identified according to their contact electrification capability. Herein, an in-depth analysis of the amino acids present in the stratum corneum of human skin is performed and these are quantified regarding triboelectric polarization. The principal focus of this study lies in analyzing and identifying the amino acids present in copious amounts in the stratum corneum to explain their positive behavior during the contact electrification process. Thus, an augmented triboelectric series of amino acids with quantified triboelectric charging polarity by scrutinizing the transfer charge, work function, and atomic percentage is presented. Furthermore, the chirality of aspartic acid as it is most susceptible to racemization with clear consequences on the human skin is detected. The study is expected to accelerate research exploiting triboelectrification and provide valuable information on the surface properties and biological activities of these important biomolecules.


Asunto(s)
Aminoácidos , Ácido Aspártico , Humanos , Epidermis , Piel , Propiedades de Superficie
20.
ACS Appl Mater Interfaces ; 16(1): 1502-1510, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38147587

RESUMEN

Development of rapid detection strategies that target potentially pathogenic bacteria has gained increasing attention due to the increasing awareness for better health and safety. In this study, we evaluate an intrinsically antimicrobial polymer, 2Gdm, which is a poly(norbornene)-based functional polymer featuring guanidinium groups as side chains, for bacterial detection by the means of triboelectric nanogenerators (TENGs) and triboelectric nanosensors (TENSs). Attachment of bacteria to the sensing layer is anticipated to alter the overall triboelectric properties of the underlying polymer layer. The positively charged guanidinium functional groups can interact with the negatively charged phospholipid bilayer of bacteria and lead to bacterial death, which can then be detected by optical microscopy, X-ray photoelectron microscopy, and more advanced self-powered sensing techniques such as TENGs and TENSs. The double bonds present along the poly(norbornene) backbone allow for thermally induced cross-linking to obtain X-2Gdm and thus rendering materials remain stable in water. By monitoring the change in voltage output after immersion in various concentrations of Gram-negative Escherichia coli (E. coli) and Gram-positive Streptococcus pneumoniae (S. pneumoniae), we have demonstrated the utility of X-2Gdm as a new polymer dielectric for autonomous bacterial detection. As the bacterial concentration increases, the amount of adsorbed bacteria also increases, resulting in a decrease in the surface potential of the X-2Gdm thin film; this reduction in surface potential can cause a decrease in the triboelectric output for both TENGs and TENSs, which serves as a key working mechanism for facile bacterial detection. TENG and TENS systems are capable of detecting E. coli and S. pneumoniae within a range of 4 × 105 to 4 × 108 CFU/mL with a limit of detection of 106 CFU/mL. This report highlights the promising prospects of employing TENGs and TENSs as innovative sensing technologies for rapid bacterial detection by leveraging the electrostatic interactions between bacterial cell membranes and cationic groups present on polymer surfaces.


Asunto(s)
Bacterias , Escherichia coli , Guanidina , Norbornanos , Poli A , Polímeros , Streptococcus pneumoniae
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