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1.
Langmuir ; 39(7): 2667-2675, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36757752

RESUMO

An absolute remedy to oil spill is still much solicited owing to empirical issues like (i) viability of the strategy right on the marine surface, (ii) operational ease of the entire process, and (iii) cost of the entire execution, which are difficult to resolve via solo operation. Current work demonstrates a hassle-free, green, and eco-friendly strategy to fix these issues simultaneously. Herein, spontaneous salt formation between carboxylic acids and primary amines, is employed against oil spill. Lime juice, a natural source of citric acid, is used directly with primary amines to congeal petrol/crude oil and spilled-over seawater (at room temperature) without any external stimulus/solvent. The chemistry behind such gelation is probed comprehensively using established physicochemical methods. A realistic model is fabricated by crude oil spilled over marine water and its removal via selective gelation. The recovery of precious oil from accumulated gel is achieved through simple pressure filtration. The feasibility and implications of this strategy is comprehensively analyzed, and an executable blueprint for real-field operation is developed.

2.
Behav Res Methods ; 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38017202

RESUMO

Deep neural networks (DNNs) have enabled recent advances in the accuracy and robustness of video-oculography. However, to make robust predictions, most DNN models require extensive and diverse training data, which is costly to collect and label. In this work, we seek to improve the codevelop pylids, a pupil- and eyelid-estimation DNN model based on DeepLabCut. We show that performance of pylids-based pupil estimation can be related to the distance of test data from the distribution of training data. Based on this principle, we explore methods for efficient data selection for training our DNN. We show that guided sampling of new data points from the training data approaches state-of-the-art pupil and eyelid estimation with fewer training data points. We also demonstrate the benefit of using an efficient sampling method to select data augmentations for training DNNs. These sampling methods aim to minimize the time and effort required to label and train DNNs while promoting model generalization on new diverse datasets.

3.
Indian J Public Health ; 67(2): 271-277, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37459024

RESUMO

Background: Post-COVID-19 cases are being reported with features of hyperinflammatory state causing multiple system dysfunctions in previously healthy children. Objectives: To describe clinical characteristics, laboratory, and radiological profile of children affected with COVID-19-related multisystem inflammatory syndrome postsecond wave in India and compare them with respect to adverse outcome. Materials and Methods: This prospective, observational study was conducted in the department of pediatrics of a tertiary care center in Eastern India over a period of 3 months. Demographic data, clinical details, biochemical parameters, and treatment with clinical outcome were recorded. Children who survived the clinical course were compared with those died during hospital stay. Results: Thirty-five children with a median age of 4.8 (3.9) years were included who were admitted between June 16 and September 15, 2021. Only 17.14% had reverse transcription-polymerase chain reaction positivity previously with 77.14% had positive COVID-19 serology. Most common features were fever (100%), edema (68.6%), gastrointestinal (71.4%), mucocuteneous (65.7%), cardiovascular (57.1%), and neurological symptoms (45.7%). Twenty (57.1%) children had shock at presentation. Decreased ejection fraction (<55%) was the most common echocardiographic feature (37.14%) followed by coronary dilatation (20%). Majority (77.14%) of the patients required intensive care with inotrope requirement in 62.86% cases. Forty percent patients were intubated with mean duration of 9.94 (±10.5) days. All patients received methylprednisolone and 76% were given intravenous immunoglobulin. Tocilizumab was used in three patients. Nine patients died (25.7%) with overall median pediatric intensive care unit stay of 13 (14) days. Conclusion: Of the parameters described, we have found shock, heart failure, neurological involvement at presentation, infancy, and laboratory parameters such as C-reactive protein, CPK, D-Dimer, and lactate dehydrogenase were the predictors of mortality.


Assuntos
COVID-19 , SARS-CoV-2 , Criança , Humanos , Pré-Escolar , Centros de Atenção Terciária , Estudos Prospectivos , Índia/epidemiologia
5.
Chemistry ; 22(2): 753-63, 2016 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-26615814

RESUMO

One-dimensional nanostructures with aggregation-induced emission (AIE) properties have been fabricated to keep the pace with growing demand from optoelectronics applications. The compounds 2-[4-(4-methylpiperazin-1-yl)benzylidene]malononitrile (PM1), 2-{4-[4-(pyridin-2-yl)piperazin-1-yl]-benzylidene}malononitrile (PM2), and 2-{4-[4-(pyrimidin-2-yl)piperazin-1-yl]benzylidene}malononitrile (PM3) have been designed and synthesized by melding piperazine and dicyanovinylene to investigate AIE in an asymmetric donor-acceptor (D-A) construct of A'-D-π-A- topology. The synthetic route has been simplified by using phenylpiperazine as a weak donor (D), dicyanovinylene as an acceptor (A), and pyridyl/pyrimidyl groups (PM2/PM3) as auxiliary acceptors (A'). It has been established that A' plays a vital role in triggering AIE in these compounds because the same D-A construct led to aggregation-caused quenching upon replacing A' with an electron-donating ethyl group (PM1). Moreover, the effect of restricted intramolecular rotation and twisted intramolecular charge transfer on the mechanism of AIE has also been investigated. Furthermore, it has been clearly shown that the optical disparities of these A'-D-π-A architectures are a direct consequence of comparative A' strength. Single-crystal X-ray analyses provided justification for role of intermolecular interactions in aggregate morphology. Electrochemical and theoretical studies affirmed the effect of the A' strength on the overall properties of the A'-D-π-A system.

6.
Chemistry ; 22(39): 13799-13804, 2016 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-27434702

RESUMO

A pioneering approach towards controlling the efficiency of saponification assisted gelation in ethyl ester based ZnII -complexes have been described. Using four new ester containing bis-salen ZnII complexes (C1-C4) involving different para-azo phenyl substituted ligands it has been clearly shown that gelation efficiency is greatly influenced by the electronic effects of the substituents (-H (C1), -CH3 (C2), -NO2 (C3), and -OCH3 (C4)). Morphological, photophysical, and rheological investigations corroborated the experimental observations well and established that gelation efficiency was enhanced with electron-withdrawing characteristics of substituents (C4

7.
Soft Matter ; 12(12): 2997-3003, 2016 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-26947708

RESUMO

Progelator complex Zn-TRPA-2 undergoes Cl(-) triggered gelation to afford ZTP2G, while Zn-TRPA-2 capped Au-NPs under similar conditions gave another gel GNZTP2G which also represents a rare nano-composite metallogel. When Zn-TRPA-2 was triggered by Cl(-) and NO3(-) simultaneously, crystals of demetalated species NA-TRPA-2 grew inside the ZTP2G matrix. Interestingly, GNZTP2G exhibits superior viscoelastic properties over ZTP2G.


Assuntos
Géis/química , Nanopartículas Metálicas/química , Ânions/química , Complexos de Coordenação/química , Cristalização , Elasticidade , Ouro/química , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Viscosidade , Zinco/química
8.
J Org Chem ; 80(21): 11115-22, 2015 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-26470031

RESUMO

A highly enantioselective synthesis of chiral chroman derivatives via an oxa-Michael-Michael cascade reaction has been developed using a bifunctional thiourea organocatalyst. The products were obtained with excellent enantioselectivities (up to >99%), good yields (up to 95%), and diastereoselectivities (up to 5:1).

9.
Iperception ; 15(2): 20416695241242346, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38577220

RESUMO

The Rotating Snakes illusion is a visual illusion where a stationary image elicits a compelling sense of anomalous motion. There have been recurring albeit anecdotal claims that the perception of illusory motion is more salient when the image consists of patterns with the combination of blue and yellow; however, there is limited empirical evidence that supports those claims. In the present study, we aimed to assess whether the Rotating Snakes illusion is more salient in its blue-yellow variation, compared to red-green and greyscale variations when the luminance of corresponding elements within the patterns were equated. Using the cancellation method, we found that the velocity required to establish perceptual stationarity was indeed greater for the stimulus composed of patterns with a blue-yellow combination than the other two variants. Our findings provide, for the first time, empirical evidence that the presence of colour affects the magnitude of illusion in the Rotating Snakes illusion.

10.
Artigo em Inglês | MEDLINE | ID: mdl-35942397

RESUMO

World is now experiencing a major health calamity due to the coronavirus disease (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus clade 2. The foremost challenge facing the scientific community is to explore the growth and transmission capability of the virus. Use of artificial intelligence (AI), such as deep learning, in (i) rapid disease detection from x-ray or computed tomography (CT) or high-resolution CT (HRCT) images, (ii) accurate prediction of the epidemic patterns and their saturation throughout the globe, (iii) forecasting the disease and psychological impact on the population from social networking data, and (iv) prediction of drug-protein interactions for repurposing the drugs, has attracted much attention. In the present study, we describe the role of various AI-based technologies for rapid and efficient detection from CT images complementing quantitative real-time polymerase chain reaction and immunodiagnostic assays. AI-based technologies to anticipate the current pandemic pattern, prevent the spread of disease, and face mask detection are also discussed. We inspect how the virus transmits depending on different factors. We investigate the deep learning technique to assess the affinity of the most probable drugs to treat COVID-19. This article is categorized under:Application Areas > Health CareAlgorithmic Development > Biological Data MiningTechnologies > Machine Learning.

11.
J Phys Chem B ; 125(49): 13482-13493, 2021 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-34865492

RESUMO

Steady-state and time-resolved spectroscopic studies demonstrate that two members of the coumarin class of dyes, coumarin 7 (C7) and coumarin 30 (C30), undergo self-aggregation in water. The development of hypsochromically shifted new absorption bands in addition to the existing monomer bands with an increase in concentration of the dyes in an aqueous medium suggests that the aggregates are of H-type. An absorption-based kinetic study reveals that the rate of aggregation of C30 is an order of magnitude faster than that of C7. Second-order rate kinetics, as obtained from the half-life (t1/2) data, implies that the aggregates are dimeric in nature. Observations of isosbestic points in area-normalized absorption spectra (ANAS) and isoemissive points in area-normalized fluorescence excitation spectra (ANFES) and time-resolved area-normalized emission spectra (TRANES) establish that ground-state monomer ⇌ dimer equilibria for both of the systems are preserved in the photoexcited state. The present study further establishes that ß-cyclodextrin is the most efficient of the three common cyclodextrins in shifting the equilibria toward the monomer by encapsulating the monomers within its cavity, making ß-CD a convenient modulator to control the self-aggregation process. Dynamic light scattering (DLS), quantum chemical calculations, and molecular docking studies provide further support to our propositions.


Assuntos
Água , beta-Ciclodextrinas , Cumarínicos , Imidazóis , Simulação de Acoplamento Molecular , Espectrometria de Fluorescência
12.
Surg Endosc ; 24(6): 1474-81, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20033729

RESUMO

BACKGROUND: Submucosal dissection is demonstrated to be a technically feasible, safe means of obtaining peroral transgastric peritoneal access for natural orifice translumenal endoscopic surgery (NOTES). The authors hypothesized that their previously described self-approximating translumenal access technique (STAT) could be used to create directed gastric submucosal tunnels permitting in-line endoscope positioning with predetermined abdominal locations that might otherwise be difficult to access. METHODS: In this study, 14 domestic farm swine underwent peroral transgastric peritoneoscopy. Under direct endoscopic visualization, a submucosal tunnel was created by dissecting between the mucosal and muscular layers of the stomach. Each tunnel was created with one of four intraabdominal locations (right upper quadrant, left upper quadrant, lesser sac, and pelvis) as the final target for in-line endoscope positioning. Once peritoneal access had been achieved, in-line positioning was assessed and peritoneoscopy was performed. The submucosal tunnels were closed with endoscopically placed clips. The animals were killed 2 weeks after the procedure, and necropsy was performed. RESULTS: Submucosal tunnels were successfully directed at predetermined intraabdominal targets in 12 of the 14 animals. The mean dissection time required to create the tunnel was 51 +/- 32 min. All the transgastric tunnels were successfully closed with endoscopically placed clips (mean, 3.2 +/- 1.1), and at necropsy showed no evidence of gastrotomy leak in any of the animals. One animal experienced a duodenal perforation unrelated to the transgastric tunneling and was killed on postoperative day 2. The remaining animals recovered and gained weight (mean, 5.5 +/- 1.2 kg) in the 2-week survival period. CONCLUSIONS: Directed submucosal dissection is technically feasible in a porcine model and permits in-line endoscope positioning with predetermined abdominal target locations. The STAT approach provides safe peritoneal access, allows for a simple reliable endoclip closure, and has an excellent short-term survival rate. This method of achieving transgastric access may be an enabling technique for future NOTES procedures.


Assuntos
Dissecação/métodos , Endoscópios Gastrointestinais , Endoscopia Gastrointestinal/métodos , Mucosa Gástrica/cirurgia , Gastrostomia/instrumentação , Animais , Modelos Animais de Doenças , Desenho de Equipamento , Feminino , Sus scrofa
13.
J Pak Med Assoc ; 59(7): 484-6, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19579742

RESUMO

The Mohr-Claussen syndrome or oro-facial-digital syndrome type II (OFD-II)] is characterised by tongue lobulation, midline cleft lip, high arched or cleft palate, broad nasal root with wide bifid nasal tip, hypertelorism, micrognathia, brachydactyly, syndactyly and polydactyly, bilateral reduplicated hallux, conductive hearing loss and normal intelligence. In view of the different modes of inheritance and the different prognoses of the two oro-facio-digital syndromes, type 1 and type 2, it is important to establish a correct diagnosis in these patients. A neonate with features of oro-facio-digital syndrome, type-II is being reported and the distinguishing clinicoradiological features with type-I are compared.


Assuntos
Fissura Palatina , Síndromes Orofaciodigitais , Humanos , Hipertelorismo
14.
Gastrointest Endosc ; 68(4): 776-82, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18926185

RESUMO

BACKGROUND: The success of endoscopic intervention in the management of uncomplicated pancreatic pseudocysts has allowed endoscopists to be more aggressive in managing complicated pancreatic fluid collections. Surgery is considered the mainstay of therapy once pancreatic abscesses develop. As a second-line treatment, endoscopic drainage of pancreatic abscess has been performed in those who are not candidates for surgery. OBJECTIVE: Our purpose was to report our experience with single-session endoscopic necrosectomy and drainage as the primary mode of treatment of infected pancreatic necrosis or abscesses. DESIGN: This was a case series. SETTING: A single endoscopy unit based at a university medical center. PATIENTS: Six consecutive patients who underwent endoscopic necrosectomy as the primary treatment modality for pancreatic abscess or necrosis between May 2006 and February 2007. MAIN OUTCOME MEASUREMENTS: Resolution of the infected pancreatic fluid collection and avoidance of surgery. RESULTS: Successful single-session endoscopic necrosectomy was performed in all 6 patients with impressive and immediate symptom relief. None needed surgery or other endoscopic or percutaneous interventions. Patients were discharged from the hospital in a median of 8.5 days. Complete resolution of pancreatic lesions were noted in 5 of 6 patients (1 patient had a small residual cyst) in median follow-up of 3.5 months (range 3-11 months). CONCLUSIONS: Endoscopic necrosectomy can be performed safely and efficiently for the primary treatment of pancreatic necrosis and abscess. Our data suggest that aggressive single-session necrosectomy can be adequate for the complete removal of infected and necrotic debris.


Assuntos
Abscesso/cirurgia , Drenagem/métodos , Endoscopia do Sistema Digestório/métodos , Pancreatopatias/cirurgia , Adolescente , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Necrose , Resultado do Tratamento
15.
ACS Omega ; 3(5): 5417-5425, 2018 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-30023918

RESUMO

Manipulating gelation properties of the isomeric zinc-terpyridine complexes C-1 (nongelator) and C-2 (gelator) using three different luminescent dyes, viz., acridine yellow (AY), ethidium bromide (EB), and azido-boron dipyrromethene, have been described. Hybrid gels created by the combination of C-1, C-2, and above-mentioned dyes have been termed complex-luminogen mixed gels (CLMGs). Ensuing CLMGs have been thoroughly characterized by spectral, morphological, and rheological studies. Cytotoxicity measurements and imaging against breast cancer cell line MDA-MB-231 unveiled that three out of the five CLMGs can be effectively used for cell imaging. Interestingly, direct use of the metal-containing hybrid gels for live cell imaging which is a distinctive approach, has been successfully achieved with significantly encouraging results.

16.
Eur J Rheumatol ; 4(3): 178-183, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29163999

RESUMO

OBJECTIVE: To assess the long-term outcome of lupus nephritis in children with systemic lupus erythematosus followed up over 12 years at a tertiary care teaching hospital in Eastern India. MATERIAL AND METHODS: This is a retrospective observational study of the clinicopathological presentation, management, and outcome in 46 children with lupus nephritis over a period of 12 years at a tertiary teaching hospital in Eastern India. Mortality was compared between different lupus classes and therapy groups with Kaplan-Meier analysis and log-rank test. RESULTS: The incidence of lupus nephritis was 58.97% [95% confidence interval (CI) 48.06%-59.89%] with the mean age at presentation being 10.2±2.43 years (range 5.5-14.5) years. Majority belonged to class IV (30.43%), followed by class II (26.91%), class III (23.91), and class V (8.70%). Outcome analysis of children with lupus nephritis over 12 years revealed that 24 (52.17%) achieved complete remission of disease activity, 5 attained partial remission, 4 continued to have active disease, 5 developed end-stage renal disease (ESRD), and 8 died. Overall mortality thus observed was 17.39% with septicemia in the background of ESRD being the commonest cause. No significant difference in mortality was observed between different lupus nephritis classes or therapy arm groups. CONCLUSION: The study throws light on various aspects of lupus nephritis and their long-term outcome patterns in children from developing countries such as India.

17.
Sci Rep ; 7(1): 355, 2017 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-28336970

RESUMO

Steep-slope transistors allow to scale down the supply voltage and the energy per computed bit of information as compared to conventional field-effect transistors (FETs), due to their sub-60 mV/decade subthreshold swing at room temperature. Currently pursued approaches to achieve such a subthermionic subthreshold swing consist in alternative carrier injection mechanisms, like quantum mechanical band-to-band tunneling (BTBT) in Tunnel FETs or abrupt phase-change in metal-insulator transition (MIT) devices. The strengths of the BTBT and MIT have been combined in a hybrid device architecture called phase-change tunnel FET (PC-TFET), in which the abrupt MIT in vanadium dioxide (VO2) lowers the subthreshold swing of strained-silicon nanowire TFETs. In this work, we demonstrate that the principle underlying the low swing in the PC-TFET relates to a sub-unity body factor achieved by an internal differential gate voltage amplification. We study the effect of temperature on the switching ratio and the swing of the PC-TFET, reporting values as low as 4.0 mV/decade at 25 °C, 7.8 mV/decade at 45 °C. We discuss how the unique characteristics of the PC-TFET open new perspectives, beyond FETs and other steep-slope transistors, for low power electronics, analog circuits and neuromorphic computing.


Assuntos
Nanotecnologia/instrumentação , Nanotecnologia/métodos , Nanofios/química , Transistores Eletrônicos , Fenômenos Eletromagnéticos
18.
Chem Commun (Camb) ; 52(19): 3840-3, 2016 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-26868265

RESUMO

The proficiency of the cyclometalated iridium complexes [(η(5)-C5Me5)IrCl(L1)] (1), [(η(5)-C5Me5)IrCl(L2)] (2) and [(η(5)-C5Me5)IrCl(L3)] (3) has been examined towards photochemical water oxidation. The involvement of Ir(iv/v) in the catalytic process has been explored via CV, UV/vis, XPS spectroscopic studies and appreciable TON relative to the theoretical value of 1 from GC.

20.
Org Lett ; 17(13): 3302-5, 2015 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-26106952

RESUMO

Silver-catalyzed interrupted Feist-Bénary reaction is described for the efficient enantioselective synthesis of dihydrofuran heterocycles. A new method has been developed for the silver(I)-(R)-BINAP complex mediated aldol-cycloisomerization cascade reaction between ynones and 1,3-diketones to provide functionalized dihydrofurans with moderate to good yields (up to 95%) and good to excellent enantiomeric excess (up to 98%). The presence of an exocyclic double bond and hydroxy group in the dihydrofuran products provides wide scope for further structural manipulation.

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