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1.
Appl Radiat Isot ; 200: 110966, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37566947

RESUMO

The true coincidence summing correction factor for a Broad Energy Germanium detector has been calculated at far and close geometry set-up using radioactive γ-ray sources. The correction factors were calculated using both experimental and analytical methods. Geant4 simulation was done to calculate the full-energy peak and total efficiencies of the detector. Standard, as well as fabricated mono-energetic γ-ray sources, were used for the γ-ray efficiency measurements. The simulated efficiencies of mono-energetic γ-ray sources were matched to the experimental γ-ray efficiencies by optimizing the detector parameters. The same parameters were used to obtain the full-energy peak and total efficiencies for γ-rays of current interest. Analytical and experimental correction factors were found to agree well with each other. The coincidence summing effect is found to be significant for source-to-detector distances less than 5 cm.

2.
Arch Microbiol ; 204(6): 326, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35576077

RESUMO

Microbes live in a complex communal ecosystem. The structural complexity of microbial community reflects diversity, functionality, as well as habitat type. Delineation of ecologically important microbial populations along with exploration of their roles in environmental adaptation or host-microbe interaction has a crucial role in modern microbiology. In this scenario, reverse ecology (the use of genomics to study ecology) plays a pivotal role. Since the co-existence of two different genera in one small niche should maintain a strict direct interaction, it will be interesting to utilize the concept of reverse ecology in this scenario. Here, we exploited an 'R' package, the RevEcoR, to resolve the issue of co-existing microbes which are proven to be a crucial tool for identifying the nature of their relationship (competition or complementation) persisting among them. Our target organism here is Frankia, a nitrogen-fixing actinobacterium popular for its genetic and host-specific nature. According to their plant host, Frankia has already been sub-divided into four clusters C-I, C-II, C-III, and C-IV. Our results revealed a strong competing nature of CI Frankia. Among the clusters of Frankia studied, the competition index between C-I and C-III was the largest. The other interesting result was the co-occurrence of C-II and C-IV groups. It was revealed that these two groups follow the theory of resource partitioning in their lifestyle. Metabolic analysis along with their differential transporter machinery validated our hypothesis of resource partitioning among C-II and C-IV groups.


Assuntos
Frankia , Microbiota , Frankia/genética , Filogenia , Plantas , Simbiose/genética
3.
Arch Microbiol ; 204(1): 33, 2021 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-34923604

RESUMO

Soil microbial diversity consisted of both culturable and non-culturable microbes. The cultivated microbes can be identified by conventional microbiological processes. However, that is not possible for the non-culturable ones. In those cases, next-generation sequencing (NGS)-based metagenomics become useful. In this study, we targeted two very popular tea gardens of Darjeeling hills-Makaibari (Mak) and Castleton (Cas). The main difference between these two study areas is the type of manure they use. Mak is solely an organic tea garden using all organic manure and fertilizers whereas Cas uses inorganic pesticides and fertilizers. The main aim was to compare the effect of organic manure over chemical fertilizers on the soil microbiomes. We have performed the 16 s metagenomics analysis based on the V3-V4 region. Downstream bioinformatics analysis including reverse ecology was performed. We found that the overall microbial diversity is higher in Mak compared to Cas. Moreover, the use of organic manure has reduced the population of pathogenic bacteria in Mak soil when compared to Cas soil. From the observations made through the metagenomics analysis of Mak and Cas soil samples, we may conclude that the application of organic manure supports the population of good bacteria in the soil which may eventually impact the tea garden workers' health.


Assuntos
Esterco , Metagenômica , Humanos , Índia , Solo , Chá
4.
Radiat Prot Dosimetry ; 193(3-4): 247-258, 2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-33942069

RESUMO

A method has been proposed to evaluate the kinetic parameters, viz. activation energy ($E$) and order of kinetics ($b$) from a single or isolated thermoluminescence (TL) glow peak. Along with the area under the entire curve, this method uses a set of three arbitrary data points and calculates the partial area under the curve from each point to the endpoint. In this way, the entire information associated with the curve is used and the method is named as 'Three-Point Area' (TPA) method. We have applied it successfully on a number of theoretically simulated TL curves generated in One Trap One Recombination centre (OTOR) model and General-Order Kinetics (GOK) model under quasi-equilibrium approximations with linear heating scheme. The activation energies are found in good agreement with input values for both the models. For OTOR model, temperature average of order of kinetics is estimated to compare with the present result. Systematic analysis is carried out for estimation of errors inherent in the method in the purview of GOK model. A closer look on the results reveals that any set of three points, preferably chosen from the rising side of the curve, can yield activation energy and order of kinetics. The validity of the method to extract $E$ and $b$ from experimental glow curves is exemplified by considering experimental TL data reported in literature. Finally, a complete study starting from the synthesis of a new phosphor $\mathrm{K_2SrP_2O_7:Pr} $ and analysis of the recorded TL data to estimate $E$ and $b$ employing the TPA method has been reported.


Assuntos
Dosimetria Termoluminescente , Cinética , Temperatura
5.
Soft Matter ; 17(23): 5700-5710, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34008689

RESUMO

Electrophoresis of a charged dielectric hydrophobic colloid embedded in a charged hydrogel medium is addressed. A slip velocity condition at the particle surface is considered. The characteristic of the gel electrophoresis is different compared with the free-solution electrophoresis due to the presence of immobile charges of the gel medium, which induces a strong background electroosmotic flow and modifies the Debye layer of the colloid. The gel electrophoresis of the dielectric hydrophobic charged colloid is made based on first-order perturbation analysis. A closed form solution involving simple exponential integrals for the mobility is derived, which reduces to several existing mobility expressions under limiting conditions such as for the gel electrophoresis of hydrophilic particles and a hydrophobic colloid in free-solution electrophoresis. We find that the mobility reversal is achieved by varying the Debye length or gel permeability. For the present first-order perturbation analysis, unlike free-solution electrophoresis, the particle dielectric permittivity is found to influence the mobility. One of the intriguing features of the present study is the derivation of the simplified mobility expression, which can be easily computed for a given set of parameter values.

6.
Neurosci Biobehav Rev ; 122: 1-17, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33421544

RESUMO

Social rewards or punishments motivate human learning and behaviour, and alterations in the brain circuits involved in the processing of these stimuli have been linked with several neuropsychiatric disorders. However, questions still remain about the exact neural substrates implicated in social reward and punishment processing. Here, we conducted four Anisotropic Effect Size Signed Differential Mapping voxel-based meta-analyses of fMRI studies investigating the neural correlates of the anticipation and receipt of social rewards and punishments using the Social Incentive Delay task. We found that the anticipation of both social rewards and social punishment avoidance recruits a wide network of areas including the basal ganglia, the midbrain, the dorsal anterior cingulate cortex, the supplementary motor area, the anterior insula, the occipital gyrus and other frontal, temporal, parietal and cerebellar regions not captured in previous coordinate-based meta-analysis. We identified decreases in the BOLD signal during the anticipation of both social reward and punishment avoidance in regions of the default-mode network that were missed in individual studies likely due to a lack of power. Receipt of social rewards engaged a robust network of brain regions including the ventromedial frontal and orbitofrontal cortices, the anterior cingulate cortex, the amygdala, the hippocampus, the occipital cortex and the brainstem, but not the basal ganglia. Receipt of social punishments increased the BOLD signal in the orbitofrontal cortex, superior and inferior frontal gyri, lateral occipital cortex and the insula. In contrast to the receipt of social rewards, we also observed a decrease in the BOLD signal in the basal ganglia in response to the receipt of social punishments. Our results provide a better understanding of the brain circuitry involved in the processing of social rewards and punishment. Furthermore, they can inform hypotheses regarding brain areas where disruption in activity may be associated with dysfunctional social incentive processing during disease.


Assuntos
Encéfalo , Motivação , Punição , Recompensa , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Humanos , Imageamento por Ressonância Magnética , Neuroimagem
7.
Ann Pharm Fr ; 79(4): 418-430, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33515589

RESUMO

OBJECTIVE: The research aims for finding the possibility of buccal delivery of celecoxib from an in situ mucoadhesive nanogel, and in vitro evaluation of the gel to evidence the enhanced permeation of drug from buccal mucosa. MATERIALS AND METHODS: Six formulations of celecoxib loaded NLCs were prepared using stearic acid and oleic acid in different ratio in aqueous solution of poloxamer by emulsion solvent evaporation technique. The physicochemical evaluations of the celecoxib loaded NLC (CeL-NLC) were carried out. The formulation F4 was selected as the best and subjected for FTIR, DSC, PXRD, and surface morphology study. In situ mucoadhesive gel was prepared with F4 in HPC, HPMC and Carbopol 934 gelling systems. The gels were evaluated for their mechanical and rheological properties and in vitro permeation studies through rabbit oral mucosa. RESULTS: The selected process at high shear homogenization could yield nanoparticles of desired physiochemical properties. The drug and excipients were compatible as disseminated from FTIR study. Transformation of the crystal form to amorphous form of celecoxib was revealed by the solid-state characterization studies. The AFM study unfold the formation of discrete asymmetric nano particles. All mucoadhesive gels found to have good mucoadhesion and rheological property with good in vitro permeation of drug. A comparative study and statistical analysis unveiled that gel containing Carbopol 934 was found to be the best mucoadhesive in situ gel of nano particles of celecoxib with enhanced permeation parameters. CONCLUSION: Therefore, the above in vitro evaluation of in situ mucoadhesive nano gel proved the potential of the formulation as a promising buccal delivery of celecoxib.


Assuntos
Nanopartículas , Poloxâmero , Animais , Celecoxib , Sistemas de Liberação de Medicamentos , Géis , Nanogéis , Coelhos
8.
Mymensingh Med J ; 29(4): 991-1000, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33116107

RESUMO

The incidence of acute kidney injury (AKI) during the treatment with gentamicin (GM) is very common in hospitalized patients. Green coffee bean, containing chlorogenic acid (CGA) has been reported to improve non communicable diseases. In the present study, CGA enriched fraction of green coffee bean was evaluated on GM induced nephrotoxicity in rats. It was a preclinical case-controlled experimental intervention conducted in the Department of Pharmacology, R G Kar Medical College, Kolkata, India from 2016-2019 using animal model. CGA content of green coffee bean extract (GCBE) was isolated and quantified by high performance thin layer chromatography (HPTLC) (6.426%). The rats were treated with GCBE at the dose of 100, 200 and 400mg/kg in gentamicin (GM) induced AKI for five consecutive days. At day 6, the renal function was assessed through analysing urine, blood and renal tissues. GCBE dose dependently and significantly (p<0.001) lowered blood urea, creatinine and potassium while, enhanced sodium compared to AKI control. Moreover, it showed significant elevation in glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) and reduction in lipid peroxides (p<0.001). It was suggested that chlorogenic acid of green coffee seed can protect kidney through down regulation of p53 transcription factor and thereby attenuation of oxidative stress, inflammation and apoptotic process in renal tubules.


Assuntos
Ácido Clorogênico , Café , Animais , Ácido Clorogênico/metabolismo , Café/metabolismo , Gentamicinas/toxicidade , Humanos , Índia , Rim , Estresse Oxidativo , Ratos
9.
Phys Rev Lett ; 125(13): 132501, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-33034500

RESUMO

We report the first observation of two wobbling bands in ^{183}Au, both of which were interpreted as the transverse wobbling (TW) band but with different behavior of their wobbling energies as a function of spin. It increases (decreases) with spin for the positive (negative) parity configuration. The crucial evidence for the wobbling nature of the bands, dominance of the E2 component in the ΔI=1 transitions between the partner bands, is provided by the simultaneous measurements of directional correlation from the oriented states ratio and the linear polarization of the γ rays. Particle rotor model calculations with triaxial deformation reproduce the experimental data well. A value of spin, I_{m}, has been determined for the observed TW bands below which the wobbling energy increases and above which it decreases with spin. The nucleus ^{183}Au is, so far, the only nucleus in which both the increasing and the decreasing parts are observed and thus gives the experimental evidence of the complete transverse wobbling phenomenon.

10.
Phys Rev E ; 102(3-1): 032601, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33075919

RESUMO

A theoretical study on the electrophoresis of a soft particle is made by taking into account the ion steric interactions and ion partitioning effects under a thin Debye layer consideration with negligible surface conduction. Objective of this study is to provide a simple expression for the mobility of a soft particle which accounts for the finite-ion-size effect and the ion partitioning arise due to the Born energy difference between two media. The Donnan potential in the soft layer is determined by considering the ion steric interactions and the ion partitioning effect. The volume exclusion due to the finite ion size is considered by the Carnahan-Starling equation and the ion partitioning is accounted through the difference in Born energy. The modified Poisson-Boltzmann equation coupled with Stokes-Darcy-Brinkman equations are considered to determine the mobility. A closed-form expression for the electrophoretic mobility is obtained, which reduces to several existing expressions for mobility under various limiting cases.

11.
Eur Cell Mater ; 40: 38-57, 2020 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-32696976

RESUMO

Surgical site infections after orthopaedic surgery using fracture fixation devices or endosseous implants create major surgical challenges with severe adverse effects, such as osteomyelitis. These infections are frequently caused by Staphylococcus aureus, often with high resistance to antibiotics, such as methicillin-resistant Staphylococcus aureus (MRSA). Due to the formation of impenetrable biofilms on implant surfaces, systemic antibiotic treatment has become exceedingly difficult. New solutions are pursued by combining several drugs using a controlled delivery system from specifically engineered implant surfaces. A sol-gel coating on titanium implants was previously developed with 20 wt % vancomycin and 30 wt % farnesol, with suppression of MRSA in vitro. The present study investigated the efficacy of sol-gel film coatings for controlled dual local delivery over 4 weeks utilising a rat infection model. The findings confirmed the viability of this new concept in vivo based on the differences observed between coatings containing vancomycin alone (SGV) and the dual-drug-containing coating with vancomycin and farnesol (SGVF). While both the SGVF and SGV coatings facilitated excellent preservation of the osseous microarchitecture, SGVF coating displayed a slightly higher potency for suppressing MRSA infiltration than SGV, in combination with a lower reactive bone remodelling activity, most likely by disturbing biofilm formation. The next step for advancing the concept of dual-drug delivery from sol-gel coatings to the clinic and confirming the promising effect of the SGVF coatings on reactive bone remodelling and suppressing MRSA infiltration is a study in a larger animal species with longer time points.


Assuntos
Sistemas de Liberação de Medicamentos , Farneseno Álcool/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Vancomicina/farmacologia , Animais , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/microbiologia , Osso e Ossos/patologia , Materiais Revestidos Biocompatíveis/farmacologia , Farneseno Álcool/administração & dosagem , Farneseno Álcool/uso terapêutico , Masculino , Projetos Piloto , Ratos Sprague-Dawley , Infecções Estafilocócicas/diagnóstico por imagem , Vancomicina/administração & dosagem , Vancomicina/uso terapêutico , Microtomografia por Raio-X
12.
J Phys Condens Matter ; 32(26): 264001, 2020 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-32106095

RESUMO

Ti-6 wt% Al-4 wt% V (Ti64) is an α + ß titanium alloy, in which the alloying components strongly affect the mechanical properties. In this report, element partitioning effects in Ti64 are investigated by using the first-principles phase field (FPPF) method, which has recently been proposed by our group. In the FPPF method, the local free energy is calculated using a cluster expansion method in combination with density functional theory and the temperature effect is incorporated using potential renormalization theory. We have succeeded in identifying enrichment of Al (V) in the α (ß) phase, i.e., the clear evidence for the element partitioning effects of Al and V, without using any thermodynamical parameter. The transformation of the ß phase and the α phase in microstructure is investigated by varying the V and Al concentrations by a small amount. Our results are in excellent agreement with the recent experimental results, showing the validity of the FPPF method for ternary alloys.

13.
Schizophr Res ; 225: 63-68, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32037203

RESUMO

The GAP multidisciplinary study carried out in South London, recruited 410 first episode of psychosis patients and 370 controls; the aim was to elucidate the multiple genetic and environmental factors influencing the onset and outcome of psychosis. The study demonstrated the risk increasing effect of adversity in childhood (especially parental loss, abuse, and bullying) on onset of psychosis especially positive symptoms. Adverse life events more proximal to onset, being from an ethnic minority, and cannabis use also played important roles; indeed, one quarter of new cases of psychosis could be attributed to use of high potency cannabis. The "jumping to conclusions" bias appeared to mediate the effect of lower IQ on vulnerability to psychosis. We confirmed that environmental factors operate on the background of polygenic risk, and that genetic and environment act together to push individuals over the threshold for manifesting the clinical disorder. The study demonstrated how biological pathways involved in the stress response (HPA axis and immune system) provide important mechanisms linking social risk factors to the development of psychotic symptoms. Further evidence implicating an immune/inflammatory component to psychosis came from our finding of complement dysregulation in FEP. Patients also showed an upregulation of the antimicrobial alpha-defensins, as well as differences in expression patterns of genes involved in NF-κB signaling and Cytokine Production. Being of African origin not only increased risk of onset but also of a more difficult course of illness. The malign effect of childhood adversity predicted a poorer outcome as did continued use of high potency cannabis.


Assuntos
Sistema Hipotálamo-Hipofisário , Transtornos Psicóticos , Criança , Etnicidade , Humanos , Londres , Grupos Minoritários , Sistema Hipófise-Suprarrenal , Transtornos Psicóticos/epidemiologia , Transtornos Psicóticos/genética , Fatores de Risco
14.
Psychopharmacology (Berl) ; 237(4): 1121-1130, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31915861

RESUMO

RATIONALE: Stress is a risk factor for psychosis and treatments which mitigate its harmful effects are needed. Cannabidiol (CBD) has antipsychotic and anxiolytic effects. OBJECTIVES: We investigated whether CBD would normalise the neuroendocrine and anxiety responses to stress in clinical high risk for psychosis (CHR) patients. METHODS: Thirty-two CHR patients and 26 healthy controls (HC) took part in the Trier Social Stress Test (TSST) and their serum cortisol, anxiety and stress associated with public speaking were estimated. Half of the CHR participants were on 600 mg/day of CBD (CHR-CBD) and half were on placebo (CHR-P) for 1 week. RESULTS: One-way analysis of variance (ANOVA) revealed a significant effect of group (HC, CHR-P, CHR-CBD (p = .005) on cortisol reactivity as well as a significant (p = .003) linear decrease. The change in cortisol associated with experimental stress exposure was greatest in HC controls and least in CHR-P patients, with CHR-CBD patients exhibiting an intermediate response. Planned contrasts revealed that the cortisol reactivity was significantly different in HC compared with CHR-P (p = .003), and in HC compared with CHR-CBD (p = .014), but was not different between CHR-P and CHR-CBD (p = .70). Across the participant groups (CHR-P, CHR-CBD and HC), changes in anxiety and experience of public speaking stress (all p's < .02) were greatest in the CHR-P and least in the HC, with CHR-CBD participants demonstrating an intermediate level of change. CONCLUSIONS: Our findings show that it is worthwhile to design further well powered studies which investigate whether CBD may be used to affect cortisol response in clinical high risk for psychosis patients and any effect this may have on symptoms.


Assuntos
Ansiedade/tratamento farmacológico , Canabidiol/administração & dosagem , Transtornos Psicóticos/tratamento farmacológico , Comportamento Social , Estresse Psicológico/tratamento farmacológico , Adolescente , Adulto , Ansiolíticos/administração & dosagem , Antipsicóticos/administração & dosagem , Ansiedade/sangue , Ansiedade/psicologia , Método Duplo-Cego , Feminino , Humanos , Hidrocortisona/sangue , Masculino , Transtornos Psicóticos/sangue , Transtornos Psicóticos/psicologia , Fatores de Risco , Fala/efeitos dos fármacos , Fala/fisiologia , Estresse Psicológico/sangue , Estresse Psicológico/psicologia , Resultado do Tratamento , Adulto Jovem
15.
Psychol Med ; 50(11): 1862-1871, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31422779

RESUMO

BACKGROUND: Evidence has been accumulating regarding alterations in components of the endocannabinoid system in patients with psychosis. Of all the putative risk factors associated with psychosis, being at clinical high-risk for psychosis (CHR) has the strongest association with the onset of psychosis, and exposure to childhood trauma has been linked to an increased risk of development of psychotic disorder. We aimed to investigate whether being at-risk for psychosis and exposure to childhood trauma were associated with altered endocannabinoid levels. METHOD: We compared 33 CHR participants with 58 healthy controls (HC) and collected information about previous exposure to childhood trauma as well as plasma samples to analyse endocannabinoid levels. RESULTS: Individuals with both CHR and experience of childhood trauma had higher N-palmitoylethanolamine (p < 0.001) and anandamide (p < 0.001) levels in peripheral blood compared to HC and those with no childhood trauma. There was also a significant correlation between N-palmitoylethanolamine levels and symptoms as well as childhood trauma. CONCLUSIONS: Our results suggest an association between CHR and/or childhood maltreatment and elevated endocannabinoid levels in peripheral blood, with a greater alteration in those with both CHR status and history of childhood maltreatment compared to those with either of those risks alone. Furthermore, endocannabinoid levels increased linearly with the number of risk factors and elevated endocannabinoid levels correlated with the severity of CHR symptoms and extent of childhood maltreatment. Further studies in larger cohorts, employing longitudinal designs are needed to confirm these findings and delineate the precise role of endocannabinoid alterations in the pathophysiology of psychosis.


Assuntos
Experiências Adversas da Infância/psicologia , Amidas/sangue , Ácidos Araquidônicos/sangue , Endocanabinoides/sangue , Etanolaminas/sangue , Ácidos Palmíticos/sangue , Alcamidas Poli-Insaturadas/sangue , Transtornos Psicóticos/sangue , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Sintomas Prodrômicos , Escalas de Graduação Psiquiátrica , Transtornos Psicóticos/etiologia , Fatores de Risco , Adulto Jovem
16.
Lupus ; 28(14): 1656-1662, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31679449

RESUMO

OBJECTIVE: Non-infectious myelitis in systemic lupus erythematosus (SLE) may be due to SLE myelitis, comorbid multiple sclerosis (MS), or neuromyelitis optica (NMO). We compared characteristics of these three conditions in SLE patients at a large academic institution. METHODS: We searched for neurologic diagnoses of SLE myelitis, NMO myelitis, and MS myelitis among 2297 patients with at least four 1997 American College of Rheumatology revised criteria for SLE between 2000 and 2015. Each subject was reviewed by a neurologist to confirm the underlying neurologic diagnosis. Demographic, clinical, laboratory, and radiographic data were extracted and compared using Fisher's exact test, analysis of variance, and Wilcoxon rank-sum test. RESULTS: Fifteen of the 2297 subjects with SLE (0.7%) met criteria for a spinal cord syndrome: seven had SLE myelitis, three had AQP4 seropositive NMO, and five had MS. The median SLE Disease Activity Index 2000 score at time of neurologic syndrome presentation was higher in SLE myelitis subjects (8, interquartile range (IQR) 7-16) compared with subjects with NMO (6, IQR 0-14) or MS (2, IQR 0-4), p = 0.02. Subjects with SLE myelitis were also more likely to have elevated anti-dsDNA antibodies at presentation (86%) compared with subjects with NMO (33%) or MS (0%), p = 0.03. CONCLUSION: Myelitis occurs rarely among patients with SLE. Compared with subjects with SLE + NMO and subjects with SLE + MS, subjects with SLE myelitis had higher SLE disease activity at presentation.


Assuntos
Lúpus Eritematoso Sistêmico/diagnóstico , Esclerose Múltipla/diagnóstico , Neuromielite Óptica/diagnóstico , Doenças da Medula Espinal/complicações , Medula Espinal/patologia , Adulto , Autoanticorpos/análise , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Índice de Gravidade de Doença
17.
Heliyon ; 5(9): e02416, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31538112

RESUMO

In this study, the heat transfer characteristics of a new class of nanofluids made from mango bark was numerically simulated and studied during turbulent flow through a double pipe heat exchanger. A range of volume fractions was considered for a particle size of 100 nm. A two-phase flow was considered using the mixture model. The mixture model governing equations of continuity, momentum, energy and volume fraction were solved using the finite-volume method. The results showed an increase of the Nusselt number by 68% for a Reynolds number of 5,000 and 45% for a Reynolds number of 13 000, and the heat transfer coefficient of the nanofluid was about twice that of the base fluid. In addition, the Nusselt number decreased by an average value of 0.76 with an increase of volume fraction by 1%. It was also found that there was a range of Reynolds numbers in which the trend of the average heat transfer coefficient of the nanofluid was completely reversed, and several plots showing zones of higher heat transfer which if taken advantage of in design will lead to higher heat transfer while avoiding other zones that have low heat transfer. It is hoped that these results will influence the thermal design of new heat exchangers.

18.
Sci Rep ; 9(1): 11101, 2019 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-31366931

RESUMO

We investigated the mechanical unfolding of single spectrin molecules over a broad range of loading rates and thus unfolding forces by combining magnetic tweezers with atomic force microscopy. We find that the mean unfolding force increases logarithmically with loading rate at low loading rates, but the increase slows at loading rates above 1pN/s. This behavior indicates an unfolding rate that increases exponentially with the applied force at low forces, as expected on the basis of one-dimensional models of protein unfolding. At higher forces, however, the increase of the unfolding rate with the force becomes faster than exponential, which may indicate anti-Hammond behavior where the structures of the folded and transition states become more different as their free energies become more similar. Such behavior is rarely observed and can be explained by either a change in the unfolding pathway or as a reflection of a multidimensional energy landscape of proteins under force.


Assuntos
Espectrina/química , Microscopia de Força Atômica/métodos , Conformação Proteica , Desnaturação Proteica , Dobramento de Proteína , Desdobramento de Proteína , Termodinâmica
19.
Phys Rev E ; 98(2-1): 023103, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30253472

RESUMO

A theoretical study on the electrophoresis of a soft particle made up of a charged hydrophobic inner core surrounded by polyelectrolyte layer (PEL) is made. The dielectric permittivity of the PEL and aqueous solution are considered to be different, which creates the ion partitioning effect. The ion partitioning effect, which is accounted by the Born energy difference, modifies the distribution of mobile ions in the PEL and hence alters the particle electrophoresis. The combined effects of core hydrophobicity and the ion partitioning effect on the mobility are determined based on the Debye-Huckel approximation under a thin Debye layer assumption. An analytic expression for the electrophoretic mobility taking into account the core hydrophobicity and ion partitioning effect is obtained. The occurrence of zero mobility and reversal of mobility of the soft particle is illustrated.

20.
Opt Lett ; 43(11): 2668-2671, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29856388

RESUMO

We have observed directional spontaneous emission of rhodamine 6G dye deposited on top of a silver grating and found that its angular distribution patterns were very different in TE and TM polarizations. The latter was related to the dispersion curves determined based on the polarized reflection spectra measured at multiple incidence angles. The most intriguing finding of this Letter was a resonance, which was coupled with TE-polarized light and determined the characteristic double-crescent patterns in the TE-polarized spontaneous emission. This observation, as well as nearly similar resonance observed in TM polarization, was tentatively explained in terms of leaky waveguide modes supported by a film of dye-doped polymer.

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