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1.
Chromosoma ; 132(4): 305-315, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37615728

RESUMO

Nucleolin is a multifunctional RNA-binding protein that resides predominantly not only in the nucleolus, but also in multiple other subcellular pools in the cytoplasm in mammalian cells, and is best known for its roles in ribosome biogenesis, RNA stability, and translation. During early mitosis, nucleolin is required for equatorial mitotic chromosome alignment prior to metaphase. Using high resolution fluorescence imaging, we reveal that nucleolin is required for multiple centrosome-associated functions at the G2-prophase boundary. Nucleolin depletion led to dissociation of the centrosomes from the G2 nuclear envelope, a delay in the onset of nuclear envelope breakdown, reduced inter-centrosome separation, and longer metaphase spindles. Our results reveal novel roles for nucleolin in early mammalian mitosis, establishing multiple important functions for nucleolin during mammalian cell division.


Assuntos
Nucleolina , Fuso Acromático , Animais , Fuso Acromático/metabolismo , Centrossomo/metabolismo , Mitose , Vertebrados , Mamíferos
2.
Langmuir ; 40(21): 11023-11029, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38748850

RESUMO

The bolometer is developed using single-walled carbon nanotubes (SWCNT) anchored with semiconductor nanoparticles of cadmium sulfide, stannous disulfide, and zinc oxide (ZnO). The bolometric responses were recorded at varying temperatures from 10 K to room temperature. The anchored SWCNTs provided a higher temperature coefficient of resistance (TCR) than pristine SWCNTs. The largest TCR is recorded from SWCNTs/ZnO (-0.11%/K) at room temperature, which is 200% higher than pristine SWCNTs. The largest photoresponsivities of SWCNTs/ZnO under near-infrared (NIR) and wide wavelength source (200-1200 nm) illuminations are 5.06 and 37.51 mV/W, respectively. The extraordinary performance of SWCNTs/ZnO stands out at ∼17 × 104% under IR illumination. The study presents a significant advancement in the development of high-performance SWCNT bolometric materials by anchoring with semiconductor nanoparticles.

3.
Environ Manage ; 73(6): 1180-1200, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38489036

RESUMO

Global climate change has seriously threatened agriculture and connected sectors, especially in developing countries like India. The Brahmaputra Valley in Assam, Northeast India, is vulnerable to climate change due to its agrarian economy, fragile geo-ecological setting, recurrent floods and droughts, and poor socioeconomic conditions of the farmers. The climate-induced hindrances faced by the rice farming community of this region and the local adaptation practices they employ have not been adequately studied. Therefore, we carried out a survey among 635 rice farmers across four agro-climatic zones of Assam, namely the Upper Brahmaputra Valley Zone, North Bank Plain Zone, Central Brahmaputra Valley Zone, and Lower Brahmaputra Valley Zone, to understand how they perceive and respond to climatic changes. The survey revealed that all the respondents have perceived an increase in ambient temperature, and 65% of the respondents have perceived a slight change in rainfall characteristics over the years. Most farmers reported adjusting the existing farming practices and livelihood choices to adapt to the changing climate. Farming adjustments were made mainly in terms of field preparation and management of water, rice variety, nutrients, and pests. Environmental variables like rainfall, flood, drought, and pest level, and socioeconomic variables like family size, education, farming experience, training, digital media exposure, and land area were found to influence farmers' adaptation choices. The findings imply that policies to strengthen flood, drought, pest management, education, land-use planning, agricultural training, and digital media applications in agriculture are needed for effective climate change adaptation in this region.


Assuntos
Agricultura , Mudança Climática , Fazendeiros , Oryza , Índia , Agricultura/métodos , Humanos , Inquéritos e Questionários , Secas , Pessoa de Meia-Idade
4.
BMC Oral Health ; 24(1): 451, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38614977

RESUMO

BACKGROUND AND OBJECTIVE: The most frequently seen intra-oral soft tissue is the gingiva. Most often, it is seen as coral-pink tissue that surrounds the neck of the teeth. Gingiva that encircles the tooth necks and covers the alveolar processes of the jaws is an intra-oral tissue that exhibits biomimetic features. The wide range of colors of the gingiva depends on the configuration of gingival vascularity, the degree of epithelial cornification, level of melanogenesis, and the depth of epithelialization. However, the color of the gingiva varies depending on the degree of melanin pigmentation. The current study aimed to identify the different distribution patterns of gingival color and determine the correlation between skin color, gender, and geographical area of origin. MATERIALS AND METHODS: A total of 839 subjects were involved in the study where the gingival color and skin tone were measured using the Dummett-Gupta Oral pigmentation Index (DOPI) combined with VITA VMK MASTER and skin shade method developed by Revlon (USA) and L'Oreal (France) for makeup foundation shades. One investigator was calibrated for the examination of the colors after being tested for normal color vision and color aptitude using the line test. RESULTS: A significant association was found between skin color and gingival pigmentation (χ2 value (6) = 114.48; P = 0.001). It was also found that females (67.1%) significantly had darker gingiva than males (58.3%). The study statistics display that location of the individual was also statistically associated with melanin pigmentation of the gingiva (χ2 value (57) = 559.33; P = 0.001). CONCLUSION: The study concluded that gender, skin color, and individual location are significantly associated with gingival melanin pigmentation.


Assuntos
Doenças da Gengiva , Hiperpigmentação , Feminino , Masculino , Humanos , Gengiva , Melaninas , Pele
5.
BMC Oral Health ; 24(1): 532, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38704529

RESUMO

BACKGROUND: Successful endodontic treatment needs accurate determination of working length (WL). Electronic apex locators (EALs) were presented as an alternative to radiographic methods; and since then, they have evolved and gained popularity in the determination of WL. However, there is insufficient evidence on the post-operative pain, adequacy, and accuracy of EALs in determining WL. OBJECTIVE: The systematic review and meta-analysis aims to gather evidence regarding the effectiveness of EALs for WL determination when compared to different imaging techniques along with postoperative pain associated with WL determination, the number of radiographs taken during the procedure, the time taken, and the adverse effects. METHODS: For the review, clinical studies with cross-over and parallel-arm randomized controlled trials (RCTs) were searched in seven electronic databases, followed by cross-referencing of the selected studies and related research synthesis. Risk of bias (RoB) assessment was carried out with Cochrane's RoB tool and a random-effects model was used. The meta-analysis was performed with the RevMan software 5.4.1. RESULTS: Eleven eligible RCTs were incorporated into the review and eight RCTs into the meta-analysis, of which five had high RoB and the remaining six had unclear RoB. Following meta-analysis, no significant difference in postoperative pain was found among the EAL and radiograph groups (SMD 0.00, CI .29 to .28, 354 participants; P value = 0.98). Radiograph group showed better WL accuracy (SMD 0.55, CI .11 to .99, 254 participants; P value = 0.02), while the EAL group had 10% better WL adequacy (RR 1.10, CI 1.03-1.18, 573 participants; P value = 0.006). CONCLUSION: We found very low-certainty evidence to support the efficacy of different types of EAL compared to radiography for the outcomes tested. We were unable to reach any conclusions about the superiority of any type of EAL. Well-planned RCTs need to be conducted by standardizing the outcomes and outcome measurement methods.


Assuntos
Radiografia Dentária , Ápice Dentário , Humanos , Cavidade Pulpar/diagnóstico por imagem , Cavidade Pulpar/anatomia & histologia , Odontometria/métodos , Radiografia Dentária/métodos , Ápice Dentário/diagnóstico por imagem , Ápice Dentário/anatomia & histologia
6.
J Cell Sci ; 134(10)2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-34014309

RESUMO

In animal cells, a single cytoplasmic dynein motor mediates microtubule minus-end-directed transport, counterbalancing dozens of plus-end-directed kinesins. The remarkable ability of dynein to interact with a diverse cargo spectrum stems from its tightly regulated recruitment of cargo-specific adaptor proteins, which engage the dynactin complex to make a tripartite processive motor. Adaptor binding is governed by the homologous dynein light intermediate chain subunits LIC1 (DYNC1LI1) and LIC2 (DYNC1LI2), which exist in mutually exclusive dynein complexes that can perform both unique and overlapping functions. The intrinsically disordered and variable C-terminal domains of the LICs are indispensable for engaging a variety of structurally divergent adaptors. Here, we hypothesize that numerous spatiotemporally regulated permutations of posttranslational modifications of the LICs, as well as of the adaptors and cargoes, exponentially expand the spectrum of dynein-adaptor-cargo complexes. We thematically illustrate the possibilities that could generate a vast set of biochemical variations required to support the wide range of dynein functions.


Assuntos
Dineínas do Citoplasma , Dineínas , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Dineínas do Citoplasma/genética , Dineínas do Citoplasma/metabolismo , Complexo Dinactina/genética , Complexo Dinactina/metabolismo , Dineínas/genética , Dineínas/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/metabolismo
7.
Ann Hematol ; 102(10): 2683-2693, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37438490

RESUMO

Congenital amegakaryocytic thrombocytopenia (CAMT) is a rare, genetic, autosomal recessive disorder characterized by severe thrombocytopenia, due to inefficient bone marrow megakaryopoiesis eventually leading to aplasia. Majority of the cases are due to homozygous or compound heterozygous mutations in MPL gene encoding for thrombopoietin (THPO) receptor protein. CAMT can be diagnosed at early phase of life, with major complication of transfusion dependency and hematopoietic transplantation as only curative treatment. We have investigated the sequence variations in MPL gene of 7 bone marrow failure (BMF) subjects, who presented with clinically diverse phenotypes, through next generation sequencing (NGS). Plasma THPO levels were estimated using ELISA. Insilico sequence and structure-based analyses were performed to understand the structural and functional implications of mutations, identified through NGS. We studied 7 CAMT subjects suspected of BMF, who presented with severe thrombocytopenia followed by pancytopenia, bleeding manifestation and physical anomalies. The plasma THPO levels were significantly elevated (p<0.05) in all the cases. Molecular analysis by NGS identified 9 genomic mutations in MPL gene. These included 7 non-synonymous substitution, 1 nonsense substitution and 1 in-del mutations, of which 4 are novel mutations. Insilico analysis predicted damaging effects on THPO-R and its reduced affinity for THPO for all the identified mutations. CAMT is a rare disorder with diverse clinical phenotypes and diagnosis is challenging. The elevated plasma THPO levels should be considered for the primary diagnosis and prognosis of the disease. However, molecular analysis of MPL gene is important for the diagnosis and management of the disease through genetic counselling. Though the cytokines, THPO-R agonist are used for the treatment of CAMT, HSCT is the only curative therapy.


Assuntos
Pancitopenia , Trombocitopenia , Humanos , Trombocitopenia/diagnóstico , Pancitopenia/etiologia , Síndrome Congênita de Insuficiência da Medula Óssea/genética , Genômica , Trombopoetina/genética , Receptores de Trombopoetina/genética
8.
J Chem Phys ; 159(4)2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37522404

RESUMO

In this work, we test a recently developed method to enhance classical auxiliary-field quantum Monte Carlo (AFQMC) calculations with quantum computers against examples from chemistry and material science, representative of classes of industry-relevant systems. As molecular test cases, we calculate the energy curve of H4 and the relative energies of ozone and singlet molecular oxygen with respect to triplet molecular oxygen, which is industrially relevant in organic oxidation reactions. We find that trial wave functions beyond single Slater determinants improve the performance of AFQMC and allow it to generate energies close to chemical accuracy compared to full configuration interaction or experimental results. In the field of material science, we study the electronic structure properties of cuprates through the quasi-1D Fermi-Hubbard model derived from CuBr2, where we find that trial wave functions with both significantly larger fidelities and lower energies over a mean-field solution do not necessarily lead to AFQMC results closer to the exact ground state energy.

9.
Drug Dev Res ; 84(1): 96-109, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36435973

RESUMO

For widening the therapeutic options for Candida management, the druggability of Candida proteome was systematically investigated using an innovative pipeline of high-throughput data mining algorithms, followed by in vitro validation of the observations. Through this exercise, HIV-1 protease was found to share structural similarity with secreted aspartyl protease-3 (SAP3), a virulence protein of Candida. Using the molecular fingerprint of HIV-1 protease inhibitor GRL-09510, we performed virtual screening of peptidomimetic library followed by high-precision docking and MD simulations for discovery of SAP inhibitors. Wet-lab validation of the four shortlisted peptidomimetics revealed that two molecules, when used in combination with fluconazole, could significantly reduce the dosage of fluconazole required for 50% inhibition of Candida albicans. The SAP inhibitory activity of these peptidomimetics was confirmed through SAP assays and found to be on par with pepstatin A, a known peptidomimetic inhibitor of aspartyl proteases.


Assuntos
Ácido Aspártico Proteases , Candidíase , Peptidomiméticos , Humanos , Peptidomiméticos/farmacologia , Fluconazol/farmacologia , Ácido Aspártico Endopeptidases , Inibidores Enzimáticos
10.
BMC Oral Health ; 23(1): 562, 2023 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-37573306

RESUMO

BACKGROUND: Pain is usually subjective and thus it is challenging to describe its characteristics such as nature, intensity, and origin. Non-invasive methods such as assessing salivary alpha-amylase (SAA) may aid the practitioner to evaluate the pain intensity. Hence, the current study aimed to correlate the levels of SAA with the pain intensity in patients presenting with varied endodontic pain levels. METHODS: Sixty patients who presented with varied intensities of endodontic pain were selected for the present study out of which seven patients were excluded/dropped, leaving a total sample of fifty-five patients for assessment. Mandibular molar with symptomatic irreversible pulpitis without periapical pathology were included in the study. A 5ml of un-stimulated was obtained from the patients, following which the local anesthesia was administered. Root canal treatment was then performed and the pain scores at pre-operative and post-operative were recorded. Additionally, salivary samples were collected after emergency endodontic treatment and sent for sialochemical analysis. IBM.SPSS statistics software 23.0 was employed to assess the obtained data. RESULTS: A statistically significant drop in the pain score (P < 0.001) and SAA levels (P < 0.001) were observed post-operatively in the contract to pre-operative state. A strong positive correlation was reported between SAA levels and pain scores in patients undergoing emergency endodontic treatment at both time intervals namely pre-operative (P < 0.001) and post-operative (P < 0.001). CONCLUSION: The results of this preliminary showed a strong association between the pain score and SAA levels in patients undergoing an emergency endodontic treatment.


Assuntos
Pulpite , alfa-Amilases Salivares , Humanos , Medição da Dor , Tratamento do Canal Radicular , Pulpite/terapia , Dor , Dor Pós-Operatória
11.
BMC Oral Health ; 23(1): 849, 2023 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-37951871

RESUMO

BACKGROUND: The study aims to compare the synergistic antibacterial efficacy of different combinations of calcium hydroxide as an intracanal medicament against E. faecalis. MATERIAL AND METHODS: The current study included four hundred extracted human permanent mandibular premolar teeth. After complete chemo-mechanical preparation, the middle third of the root was sectioned using a rotary diamond disc and a total of 400 samples were obtained. The specimens were inoculated with E. faecalis for 21 days. After that, specimens were divided into five groups (n = 80) based on materials used for the disinfection of samples: Group I, calcium hydroxide alone; Group II, calcium hydroxide + 2% chlorhexidine gel; Group III, calcium hydroxide + 2% chitosan gel; Group IV, calcium hydroxide + 0.02% silver nanoparticle gel; Group V, calcium hydroxide + Bioactive glass S53P4. Dentin shavings from the apical third were obtained from the inner third of dentin were obtained using gates glidden no.1 to the apical depth, followed by no.2, 3, 4 and 5 analyzed for E. faecalis using the culture method. One-way analysis of variance (ANOVA) was used for data analysis, followed by post-hoc Tukey's test for multiple comparisons of means to check the difference in bacterial inhibition between the groups. RESULTS: ANOVA results revealed a significant reduction of bacterial counts in all the groups compared (p < 0.001). Intergroup comparison showed maximum bacterial reduction (p < 0.001) with calcium hydroxide + bioactive glass S53P4 compared with other groups. CONCLUSION: Synergistic effect of calcium hydroxide showed better bacterial reduction compared to calcium hydroxide alone. Among the combinations evaluated, calcium hydroxide with bioactive glass, found to be most effective compared to other groups.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Humanos , Enterococcus faecalis , Hidróxido de Cálcio/farmacologia , Prata/farmacologia , Prata/uso terapêutico , Anti-Infecciosos/farmacologia , Clorexidina/farmacologia , Irrigantes do Canal Radicular/farmacologia
12.
BMC Oral Health ; 23(1): 566, 2023 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-37574536

RESUMO

BACKGROUND: Large cavity designs and access cavities impair endodontically treated tooth fracture resistance. As the tooth's strength is known to reduce significantly after the root canal treatment, occlusal loading as a result of functions such as chewing, biting and certain parafunctional tendencies makes the endodontically treated tooth vulnerable to fracture. Hence, after endodontic treatment, it is vital to give adequate and appropriate restorative material to avoid tooth fractures. Accordingly, the choice of such restorative material should be dictated by the property of fracture resistance. OBJECTIVE: The goal of this study was to conduct a systematic review and critical analysis of available data from in vitro studies examining the fracture resistance of endodontically treated posterior teeth restored with fiber-reinforced composites. METHODOLOGY: The Preferred Reporting Items for Systematic Review and Meta-Analysis (PRIS-MA) Statement was used to guide the reporting of this systematic review A comprehensive literature search was performed using MEDLINE (via PubMed), Scopus, ScienceDirect, Google Scholar, and LILACS. A manual search of the reference lists of the articles was also performed. The databases provided a total of 796 studies from the electronic systematic search. The databases provided a total of 796 studies from the electronic systematic search. Two reviewers scrutinized the papers for eligibility based on inclusion/exclusion criteria and extracted data. The studies were assessed for their potential risk of bias. Based on modified JBI & CRIS (checklist for reporting in vitro studies) guidelines, along with the methodology and treatment objective, we have formulated 13 parameters specifically to assess the risk of bias. A total of 18 studies met the inclusion criteria and were included for qualitative analysis. Considering the high heterogeneity of the studies included, a meta-analysis could not be performed. RESULTS: The majority of the included studies had a moderate or high risk of bias. When compared to traditional hybrid composites, fiber-reinforced composites showed increased fracture resistance of endodontically treated teeth in the majority of investigations. On the other hand, limited evidence was found for the bulk fill composites. Moreover, moderate evidence was found for the fracture resistance of inlays and fiber posts with fiber-reinforced composites for core build-up in endodontically treated teeth. No evidence could be found comparing the fracture resistance of endo crowns and fiber-reinforced composites in endodontically treated teeth. CONCLUSION: According to the research, using fiber-reinforced composites instead of conventional hybrid composites improves the fracture resistance of endodontically treated teeth. However, there was a high risk of bias in the research considered. No judgments could be reached about the superiority of one material over another based-on comparisons between other core restorations.


Assuntos
Fraturas dos Dentes , Dente não Vital , Humanos , Materiais Dentários , Coroas , Fraturas dos Dentes/etiologia , Fraturas dos Dentes/prevenção & controle , Resinas Compostas , Análise do Estresse Dentário
13.
BMC Oral Health ; 23(1): 833, 2023 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-37932703

RESUMO

BACKGROUND AND OBJECTIVE: Dental panoramic radiographs are utilized in computer-aided image analysis, which detects abnormal tissue masses by analyzing the produced image capacity to recognize patterns of intensity fluctuations. This is done to reduce the need for invasive biopsies for arriving to a diagnosis. The aim of the current study was to examine and compare the accuracy of several texture analysis techniques, such as Grey Level Run Length Matrix (GLRLM), Grey Level Co-occurrence Matrix (GLCM), and wavelet analysis in recognizing dental cyst, tumor, and abscess lesions. MATERIALS & METHODS: The current retrospective study retrieved a total of 172 dental panoramic radiographs with lesion including dental cysts, tumors, or abscess. Radiographs that failed to meet technical criteria for diagnostic quality (such as significant overlap of teeth, a diffuse image, or distortion) were excluded from the sample. The methodology adopted in the study comprised of five stages. At first, the radiographs are improved, and the area of interest was segmented manually. A variety of feature extraction techniques, such GLCM, GLRLM, and the wavelet analysis were used to gather information from the area of interest. Later, the lesions were classified as a cyst, tumor, abscess, or using a support vector machine (SVM) classifier. Eventually, the data was transferred into a Microsoft Excel spreadsheet and statistical package for social sciences (SPSS) (version 21) was used to conduct the statistical analysis. Initially descriptive statistics were computed. For inferential analysis, statistical significance was determined by a p value < 0.05. The sensitivity, specificity, and accuracy were used to find the significant difference between assessed and actual diagnosis. RESULTS: The findings demonstrate that 98% accuracy was achieved using GLCM, 91% accuracy using Wavelet analysis & 95% accuracy using GLRLM in distinguishing between dental cyst, tumor, and abscess lesions. The area under curve (AUC) number indicates that GLCM achieves a high degree of accuracy. The results achieved excellent accuracy (98%) using GLCM. CONCLUSION: The GLCM features can be used for further research. After improving the performance and training, it can support routine histological diagnosis and can assist the clinicians in arriving at accurate and spontaneous treatment plans.


Assuntos
Abscesso , Cistos , Humanos , Estudos Retrospectivos , Aprendizado de Máquina
14.
Medicina (Kaunas) ; 59(4)2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37109723

RESUMO

Background and Objectives: Diagnostic evaluation with the aid of biomarkers has reached newer heights to assess disease activity. Salivary calcium, magnesium, and pH are one of the biochemical parameters which can be helpful in assessing the progression of periodontal disease. Smokers are at topnotch threat for having oral diseases, predominantly periodontal diseases. The aim of this study was to assess the salivary calcium, magnesium, and pH levels in smokers compared with non-smokers with chronic periodontitis. Materials and Methods: The current study was conducted on 210 individuals affected with generalized chronic periodontitis, with the age group between 25 and 55 years. Based on their smoking habit, an equal number of patients were categorized into two groups; namely, group I consisted of non-smokers and group II consisted of smokers. The clinical parameters that were measured included Plaque Index (PI), Gingival Index (GI), Probing Pocket Depth (PPD), and Clinical Attachment Loss (CAL). The biochemical variables that were evaluated in the current study included salivary calcium, magnesium, and pH using an AVL9180 electrolyte analyzer (Roche, Germany). The gathered data were analyzed with an unpaired t test was using SPSS 20.0. Results: A statistically significant higher PPD (p < 0.01), CAL (p < 0.05), and salivary calcium levels (p < 0.001) were observed in the smokers' compared with their non-smoking counterparts. Among the biochemical parameters, calcium showed a significantly (p < 0.001) higher level in smokers (5.79 ± 1.76) in contrast to non-smokers (3.87 ± 1.03). Additionally, a significant negative correlation (p < 0.05) between calcium and PPD was observed in non-smokers, whereas a non-significant inverse relation (p > 0.05) was seen in smokers. Conclusions: The present study indicates that the salivary calcium level can be a potential biochemical parameter to assess the progression of periodontal disease in smokers and non-smokers. Within the limitations of the current study, the salivary biomarkers appear to have an essential role in the identification and indication of the status of periodontal diseases.


Assuntos
Periodontite Crônica , Humanos , Adulto , Pessoa de Meia-Idade , Periodontite Crônica/complicações , não Fumantes , Cálcio , Magnésio , Biomarcadores , Concentração de Íons de Hidrogênio
15.
Phys Rev Lett ; 129(15): 157701, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36269972

RESUMO

It has long been realized that even a perfectly clean electronic system harbors a Landauer-Sharvin resistance, inversely proportional to the number of its conduction channels. This resistance is usually associated with voltage drops on the system's contacts to an external circuit. Recent theories have shown that hydrodynamic effects can reduce this resistance, raising the question of the lower bound of resistance of hydrodynamic electrons. Here, we show that by a proper choice of device geometry, it is possible to spread the Landauer-Sharvin resistance throughout the bulk of the system, allowing its complete elimination by electron hydrodynamics. We trace the effect to the dynamics of electrons flowing in channels that terminate within the sample. For ballistic systems this termination leads to back-reflection of the electrons and creates resistance. Hydrodynamically, the scattering of these electrons off other electrons allows them to transfer to transmitted channels and avoid the resistance. Counterintuitively, we find that in contrast to the ohmic regime, for hydrodynamic electrons the resistance of a device with a given width can decrease with its length, suggesting that a long enough device may have an arbitrarily small total resistance.


Assuntos
Elétrons , Hidrodinâmica
16.
Langmuir ; 38(34): 10400-10411, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-35973133

RESUMO

We modulate the adsorption affinities of nanoclay particles for the air-water interface by changing the cationic surface charge composition of the lipid monolayer and thereby tune the attractive electrostatic interaction between the positively charged lipid layer and the zwitterionic nanoclay particles in the water subphase. Our findings emphasize the significance of electrostatic interaction between lipids and the nanoclay, as well as its impact on the structural and viscoelastic features of the composite layer. We use surface pressure (Π)-mean molecular area (A) isotherms, atomic force microscope (AFM), Brewster angle microscopy (BAM), and energy dispersive X-ray spectrsocopy (EDXS) measurements to analyze the structure phases of lipid and lipid-nanoclay composite interfacial layer. The Π-A isotherm curve shows that the lipid-nanoclay composite layer has a larger lift-off area than the neat lipid layer, indicating that nanoparticles adsorb at the lipid layer via electrostatic interaction between lipid and nanoclay molecules. The surface density of the adsorbed nanoclay particles increases with an increase in the composition of the cationic lipid molecules. The stress relaxation response of the composite layer, measured using step compression measurements, exhibits exponential decay and ubiquitous dependence on the cationic dimyristoy-trimethylammonium propane (DMTAP) composition in the lipid layer with crossover to faster relaxation dynamics at DMTAP > 0.75. The power-law study of the frequency-dependent dynamic viscoelastic responses of the interfacial layer, measured using the barrier oscillation method, reveals a transition from glass-like response from neat lipid layer to gel-like dynamic response for the lipid-nanoclay composite layer. A solid-like behavior is evident for all the interface layers with dilation elastic modulus (E') > dilational viscous modulus (E″); however, the dynamic response of the neat layer is largely frequency-independent, whereas lipid-nanoclay composite layers with DMTAP > 0.75 reveal a frequency-dependent dynamic responses. The frequency-dependent power-law exponent of E', E″ increases on increasing the fractional composition of cationic DMTAP from 0.1 to 1.0, which forms a saturated interface of laponite particles and behaves as a viscoelastic gel in 2D.


Assuntos
Lipídeos , Água , Adsorção , Cátions , Lipídeos/química , Eletricidade Estática , Propriedades de Superfície , Viscosidade , Água/química
17.
J Chem Phys ; 156(15): 154104, 2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35459303

RESUMO

The direct energy functional minimization method using the orbital transformation (OT) scheme in the program package CP2K has been employed for Δ self-consistent field (ΔSCF) calculations. The OT method for non-uniform molecular orbitals occupations allows us to apply the ΔSCF method for various kinds of molecules and periodic systems. Vertical excitation energies of heteroaromatic molecules and condensed phase systems, such as solvated ethylene and solvated uracil obeying periodic boundary conditions, are reported using the ΔSCF method. In addition, a Re-phosphate molecule attached to the surface of anatase (TiO2) has been investigated. Additionally, we have implemented a recently proposed state-targeted energy projection ΔSCF algorithm [K. Carter-Fenk and J. M. Herbert, J. Chem. Theory Comput. 16(8), 5067-5082 (2020)] for diagonalization based SCF in CP2K. It is found that the OT scheme provides a smooth and robust SCF convergence for all investigated excitation energies and (non-)periodic systems.


Assuntos
Teoria Quântica , Uracila , Fenômenos Físicos
18.
BMC Public Health ; 22(1): 2093, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36384563

RESUMO

BACKGROUND: Rural Indians have higher mortality rates than urban Indians. However, the rural-urban gap in under-five mortality has changed is less researched. This paper aims to assess 1) whether the rural-urban gap in under-five mortality has reduced over time 2) Whether rural children are still experiencing a higher likelihood of death after eliminating the role of other socioeconomic factors 3) What factors are responsible for India's rural-urban gap in under-five mortality. METHODS: We used all rounds for National Family Health Survey data for understanding the trend of rural-urban gap in under-five mortality. Using NFHS-2019-21 data, we carried out a binary logistic regression analysis to examine the factors associated with under-five mortality. Fairlie's decomposition technique was applied to understand the relative contribution of different covariates to the rural-urban gap in under-five mortality. RESULTS: India has witnessed a more than 50% reduction in under-five mortality rate between 1992 and 93 and 2019-21. From 1992 to 93 to 2019-21, the annual decrease in rural and urban under-five mortality is 1.6% and 2.7%, respectively. Yet, rural population still contributes a higher proportion of the under-five deaths. The rural-urban gap in under-five mortality has reduced from 44 per thousand live births in 1992-1993 to 30 per thousand in 2004-2005 which further decreased to 14 per thousand in 2019-2021. There is no disadvantage for the rural children due to their place of residence if they belong to economically well-off household or their mothers are educated. It is wealth index rather than place of residence which determines the under-five mortality. Economic (50.82% contribution) and educational differential (28.57% contribution) are the main reasons for rural-urban under-five mortality gaps. CONCLUSION: The existing rural-urban gap in under-five mortality suggests that the social and health policies need to be need to reach rural children from poor families and uneducated mothers. This call for attention to ensure that the future programme must emphasize mothers from economically and educationally disadvantaged sections. While there should be more emphasis on equal access to health care facilities by the rural population, there should also be an effort to strengthen the rural economy and quality of education.


Assuntos
Mães , População Rural , Criança , Feminino , Humanos , Fatores Socioeconômicos , Escolaridade , Índia/epidemiologia
19.
World J Surg Oncol ; 20(1): 171, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35641982

RESUMO

INTRODUCTION: Pseudomyxoma peritonei (PMP) is a generalized term, usually known as "jelly belly" since 1884. Incidence is very low, 1-3 per million people per year. Because of its indolent nature, it is usually diagnosed at an advanced stage, thereby impacting the quality of life. The 5-year survival rate varies from 23 to 86% in world literature. Even 10 years and 20 years of survival have been described. With our experience, we like to propose rename of PMP as abdomino-peritoneal mucinous carcinoma (APM) as we strongly feel the time has come to specify the term and standardize the management strategy. METHODOLOGY: In the premier institute of India and as a tertiary referral center, we experienced the maximum number of advanced cases of APM. From 2012 to 2021, we analyzed all the APM patients based on a prospectively maintained computerized database in the department of surgical oncology and found the reasons for renaming from this traditional one. RESULTS: We included a total of 87 patients who underwent surgical intervention. Thirty-five patients underwent cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC), and 52 patients underwent debulking. In CRS-HIPEC patients, CC-0 was achieved in 28 patients (80%), CC-1 in 4 patients (11.4%), and CC-2 in 3 patients (8.6%). Palliative intent HIPEC was done in 3 patients (8.6%). Clavien-Dindo grade III and IV morbidity was observed in 18.8% of patients with 90 days mortality of 5.7%. CONCLUSION: With our long-term experience and advancement of scientific evidence, we like to propose a new name for PMP as APM. We strongly believe this paper will give a clear picture of this rare disease and standard management outlines.


Assuntos
Adenocarcinoma Mucinoso , Hipertermia Induzida , Neoplasias Peritoneais , Pseudomixoma Peritoneal , Adenocarcinoma Mucinoso/terapia , Humanos , Neoplasias Peritoneais/patologia , Pseudomixoma Peritoneal/patologia , Qualidade de Vida
20.
Cytopathology ; 33(4): 518-521, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34995382

RESUMO

Extra-nodal (NK/T) cell lymphoma (NKTCL) of nasal type (ENKL) presents with extranodal involvement and is associated with EBV. They are localized primarily to nasal and upper airway region but can rarely involve skin, testis, intestine, muscle, or present as a disseminated disease. We present a case of a 65-year-old male presented with bilateral orbital swelling, right parotid swelling, fever, mediastinal nodes, pleural effusion and hepatomegaly. Cytology of pleural fluid showed monomorphic lymphoid cells with folded nuclei, vesicular chromatin, inconspicuous nucleoli and granular cytoplasm. Few histiocytes showing hemophagocytosis were also noted in a background of inflammatory cells. Flow cytometric immunophenotyping of pleural fluid showed abnormal lymphoid cells which were positive for CD45, CD2 and CD56. Histopathological examination of the right eye swelling showed many atypical lymphoid cells which were positive for CD56 and negative for B and T cell markers. Based on morphological and immunophenotypic features a diagnosis of NKTCL, extra-nasal type was suggested. Patient succumbed to the disease despite aggressive therapy.


Assuntos
Linfoma Extranodal de Células T-NK , Linfoma de Células T , Idoso , Citometria de Fluxo , Humanos , Imunofenotipagem , Células Matadoras Naturais/patologia , Linfonodos/patologia , Linfoma Extranodal de Células T-NK/diagnóstico , Linfoma Extranodal de Células T-NK/patologia , Linfoma de Células T/diagnóstico , Linfoma de Células T/patologia , Masculino
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