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1.
Braz. j. biol ; 84: e255485, 2024. tab, graf
Artigo em Inglês | MEDLINE, LILACS, VETINDEX | ID: biblio-1350312

RESUMO

Abstract The current focus is on the overall pattern of seed storage present in the fragments of the soil of piedmont and alluvial landscapes of the environment. The present study predicted the seed banks of both soils of alluvial and piedmont zones in different ecological conditions and evaluate the potential of seeds in the restoration of both environments. The composition of the seed bank of soil is mainly affected by the alluvial environment and the structure of cleared area shows that more species of germinating annual grasses and growable seeds with the higher total number. Extant vegetation structures have an important role in the diversity of soil seed reservoirs, whose composition corresponded with the openness of the site. When in situ soil seed bank is recruited, it helps to restore only some components of the plant community in an alluvial environment. In our current research, it was confirmed that seed richness was higher in number at lower elevation (alluvial) than that at high elevation (piedmont). Seed richness showed a significant negative correlation with anions, cations, while significantly positive with altitude that suggests the richness pattern of the overall seed bank of the area is influenced by various environmental factors.


Resumo O foco atual está no padrão geral de armazenamento de sementes presente nos fragmentos de solo do Piemonte e nas paisagens aluviais do meio ambiente. O presente estudo previu os bancos de sementes de ambos os solos das zonas aluvial e piemontesa em diferentes condições ecológicas e avaliou o potencial das sementes na restauração de ambos os ambientes. A composição do banco de sementes do solo é afetada principalmente pelo ambiente aluvial e a estrutura da área desmatada mostra que mais espécies de gramíneas anuais em germinação e sementes cultiváveis ​​apresentam o maior número total. As estruturas da vegetação existente têm um papel importante na diversidade dos reservatórios de sementes do solo, cuja composição correspondeu à abertura do local. Quando o banco de sementes do solo in situ é recrutado, o mesmo ajuda a restaurar apenas alguns componentes da comunidade de plantas em um ambiente aluvial. Em nossa pesquisa atual, foi confirmado que a riqueza de sementes era maior em número em altitudes mais baixas (aluviais) do que em altitudes elevadas (Piemonte). A riqueza de sementes mostrou uma correlação negativa significativa com ânions, cátions, enquanto significativamente positiva com a altitude, o que sugere que o padrão de riqueza do banco geral de sementes da área é influenciado por vários fatores ambientais.


Assuntos
Solo , Banco de Sementes , Paquistão , Plantas , Sementes , Ecossistema , Poaceae
2.
ACS Sens ; 7(1): 286-295, 2022 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-34978190

RESUMO

Sensors for monitoring biomolecular dynamics in biological systems and biotechnological processes in real time, need to accurately and precisely reconstruct concentration-time profiles. This requirement becomes challenging when transport processes and biochemical kinetics are important, as is typically the case for biomarkers at low concentrations. Here, we present a comprehensive methodology to study the concentration-time profiles generated by affinity-based sensors that continuously interact with a biological system of interest. Simulations are performed for sensors with diffusion-based sampling (e.g., a sensor patch on the skin) and advection-based sampling (e.g., a sensor connected to a catheter). The simulations clarify how transport processes and molecular binding kinetics result in concentration gradients and time delays in the sensor system. Using these simulations, measured and true concentration-time profiles of insulin were compared as a function of sensor design parameters. The results lead to guidelines on how biomolecular monitoring sensors can be designed for optimal bioanalytical performance in terms of concentration and time properties.


Assuntos
Insulina , Cinética
3.
Braz. J. Biol. ; 82: 1-7, 2022. tab, graf
Artigo em Inglês | VETINDEX, VETINDEX | ID: vti-32769

RESUMO

Salmo trutta fario is the most important fish species of family Salmonidae inhibited in cool waters all over the world including the nortern parts of Pakistan. This study was aimed to find out the prey selection and feeding habits of the species. One hundred and eighty five Salmo trutta fario were captured from March 2016 to April 2017. Feeding intensity as represented by a fullness index (FI), changing with various length groups and season. Out of 185 Brown trout 24 fish stomaches were found empty. The most important and common food items of brown trout were Brachycentridae, Blepharocera, Hydropsychidae, ephemerella spp. Kruskal Wallis H-test were applied on feeding intensity groups consisting of three month group. The test statistic for K.W-H-test were (H=8.13 with df =3) had a p-value of 0.043 < (alpha=0.05 indicates favor of the alternative hypothesis of at least one difference among the feeding intensity groups. The linear relationship of N with index of relative importance and %IRI denoted by least square regression line (N = 35.2 + 22.1%IRI), shows that for 22 prey there is 1% change in IRI. The relationship between total length (mm) and fish body weight (gm) is expressed by Pearson correlation coefficient (r = 0.976), showed that total length (mm) and fish body weight (gm.) is highly correlated. Descriptive statistics are used for the stomach fullness, which shows that feeding intensity was recorded higher from March to May. A total of 2289 preys was recorded including the most common were; Trichoptera, Hydropsychidae, Brachycentridae, diptera, blepharocera, ephemerala, chironomida, honey bees, grass hopper, locust, trout egg, trochanter, plant tissue, stones were retrieved from the gut contents of brown trout. According to index of relative importance IRI% four preys represents major components of the diet. The highest IRI% was recorded in Brachycentridae (39.38%), followed by blepharocera (13.23%), [...].(AU)


Salmo trutta fario é a espécie de peixe mais importante da família dos salmonídeos, inibida em águas frias em todo o mundo, incluindo as partes do noroeste do Paquistão. Este estudo teve como objetivo conhecer a seleção de presas e os hábitos alimentares da espécie. Cento e oitenta e cinco Salmo trutta fario foram capturados de março de 2016 a abril de 2017. Intensidade de alimentação representada por um índice de plenitude (FI), mudando com vários grupos de comprimento e estação. De 185 trutas, 24 estômagos de peixes foram encontrados vazios. Os itens alimentares mais importantes e comuns da truta marrom foram brachycentridae, blepharocera, hydropsychidae, ephemerellaspp. O teste H de Kruskal Wallis foi aplicado em grupos de intensidade de alimentação consistindo de um grupo de três meses. A estatística de teste para o teste KW-H foi (H = 8,13 com df = 3) teve um valor de p de 0,043 <(alfa = 0,05 indica favor da hipótese alternativa de pelo menos uma diferença entre os grupos de intensidade de alimentação. relação de N com o índice de importância relativa e% IRI denotado pela linha de regressão do mínimo quadrado (N = 35,2 + 22,1% IRI), mostra que para 22 presas há 1% de mudança no IRI. A relação entre comprimento total (mm) e peixes o peso corporal (gm) é expresso pelo coeficiente de correlação de Pearson (r = 0,976), mostrou que o comprimento total (mm) e o peso corporal dos peixes (gm.) são altamente correlacionados. Estatísticas descritivas são usadas para a plenitude do estômago, o que mostra que a intensidade da alimentação foi registrado mais alto de março a maio. Um total de 2.289 presas foi registrado, incluindo os mais comuns foram; trichoptera, hydropsychidae, brachycentridae, diptera, blepharocera, efemérala, chironomida, abelhas, funil de grama, gafanhoto, ovo de truta, trocânter, tecido vegetal, pedras foram retiradas do intestino conteúdo de truta marrom. De acordo com o índice de importância relativa [...].(AU)


Assuntos
Animais , Truta/crescimento & desenvolvimento , Dieta/veterinária , Ração Animal
4.
Chemosphere ; 287(Pt 1): 132035, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34474383

RESUMO

Iron oxide nanostructured catalysts have emerged as potential candidates for efficient energy conversion and electrochemical energy storage devices. However, synthesis and design of nanomaterial plays a key role in its performance and efficiency. Herein, we describe a one-pot solution combustion synthesis (SCS) of α-Fe2O3 with glycine as a fuel, and a subsequent reduction step to produce iron-containing catalysts (i.e., Fe3O4, Fe-Fe3O4, and Fe0). The synthesized iron-based nanoparticles were investigated for methyl orange (MO) degradation through Microwave (MW) energy under continuous flow conditions. Fe-Fe3O4 showed higher MO degradation efficiency than α-Fe2O3, Fe3O4 and Fe0 at low absorbed MW power (i.e. 5-80 W). The enhanced degradation efficiency is associated to the combination of higher availability of electron density and higher heating effect under MW energy. Investigation of dielectric properties showed relative dielectric loss of Fe3O4, Fe-Fe3O4, and Fe0 as 3847, 2010, and 1952, respectively. The calculated average local temperature by the comparative analysis of MW treatment with conventional thermal (CT) treatment showed a marked thermal effect of MW-initiated MO degradation. This work highlights the potential of microwave-driven water depollution under continuous-flow processing conditions and demonstrates the positive impact that earth-abundant Fe catalyst synthesized by green SCS method can have over the treatment of wastewater.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Catálise , Ferro , Micro-Ondas
5.
Braz. j. biol ; 82: e239219, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1153471

RESUMO

Abstract Salmo trutta fario is the most important fish species of family Salmonidae inhibited in cool waters all over the world including the nortern parts of Pakistan. This study was aimed to find out the prey selection and feeding habits of the species. One hundred and eighty five Salmo trutta fario were captured from March 2016 to April 2017. Feeding intensity as represented by a fullness index (FI), changing with various length groups and season. Out of 185 Brown trout 24 fish stomaches were found empty. The most important and common food items of brown trout were Brachycentridae, Blepharocera, Hydropsychidae, ephemerella spp. Kruskal Wallis H-test were applied on feeding intensity groups consisting of three month group. The test statistic for K.W-H-test were (H=8.13 with df =3) had a p-value of 0.043 < (alpha=0.05 indicates favor of the alternative hypothesis of at least one difference among the feeding intensity groups. The linear relationship of N with index of relative importance and %IRI denoted by least square regression line (N = 35.2 + 22.1%IRI), shows that for 22 prey there is 1% change in IRI. The relationship between total length (mm) and fish body weight (gm) is expressed by Pearson correlation coefficient (r = 0.976), showed that total length (mm) and fish body weight (gm.) is highly correlated. Descriptive statistics are used for the stomach fullness, which shows that feeding intensity was recorded higher from March to May. A total of 2289 preys was recorded including the most common were; Trichoptera, Hydropsychidae, Brachycentridae, diptera, blepharocera, ephemerala, chironomida, honey bees, grass hopper, locust, trout egg, trochanter, plant tissue, stones were retrieved from the gut contents of brown trout. According to index of relative importance IRI% four preys represents major components of the diet. The highest IRI% was recorded in Brachycentridae (39.38%), followed by blepharocera (13.23%), Hydropsychidae (10.76%) and ephemerella spp (8.28%). The relationship between IRI and FO is (r =0.556) is moderately correlated with coefficient of determination (r2=0.31). This study will help in the development of an artificial diet for the species for better growth performance in captivity.


Resumo Salmo trutta fario é a espécie de peixe mais importante da família dos salmonídeos, inibida em águas frias em todo o mundo, incluindo as partes do noroeste do Paquistão. Este estudo teve como objetivo conhecer a seleção de presas e os hábitos alimentares da espécie. Cento e oitenta e cinco Salmo trutta fario foram capturados de março de 2016 a abril de 2017. Intensidade de alimentação representada por um índice de plenitude (FI), mudando com vários grupos de comprimento e estação. De 185 trutas, 24 estômagos de peixes foram encontrados vazios. Os itens alimentares mais importantes e comuns da truta marrom foram brachycentridae, blepharocera, hydropsychidae, ephemerellaspp. O teste H de Kruskal Wallis foi aplicado em grupos de intensidade de alimentação consistindo de um grupo de três meses. A estatística de teste para o teste KW-H foi (H = 8,13 com df = 3) teve um valor de p de 0,043 <(alfa = 0,05 indica favor da hipótese alternativa de pelo menos uma diferença entre os grupos de intensidade de alimentação. relação de N com o índice de importância relativa e% IRI denotado pela linha de regressão do mínimo quadrado (N = 35,2 + 22,1% IRI), mostra que para 22 presas há 1% de mudança no IRI. A relação entre comprimento total (mm) e peixes o peso corporal (gm) é expresso pelo coeficiente de correlação de Pearson (r = 0,976), mostrou que o comprimento total (mm) e o peso corporal dos peixes (gm.) são altamente correlacionados. Estatísticas descritivas são usadas para a plenitude do estômago, o que mostra que a intensidade da alimentação foi registrado mais alto de março a maio. Um total de 2.289 presas foi registrado, incluindo os mais comuns foram; trichoptera, hydropsychidae, brachycentridae, diptera, blepharocera, efemérala, chironomida, abelhas, funil de grama, gafanhoto, ovo de truta, trocânter, tecido vegetal, pedras foram retiradas do intestino conteúdo de truta marrom. De acordo com o índice de importância relativa IRI%, quatro presas representam os principais componentes da dieta. O maior IRI% foi registrado em brachycentridae (39,38%), seguido por blepharocera (13,23%), hydropsychidae (10,76%) e ephemerellaspp (8,28%). A relação entre IRI e FO é (r = 0,556) está moderadamente correlacionada com o coeficiente de determinação (r2 = 0,31). Este estudo auxiliará no desenvolvimento de uma dieta artificial para a espécie para melhor desempenho de crescimento em cativeiro.


Assuntos
Animais , Truta , Rios , Paquistão , Abelhas , Dieta , Hábitos
6.
Braz J Biol ; 84: e255485, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34878007

RESUMO

The current focus is on the overall pattern of seed storage present in the fragments of the soil of piedmont and alluvial landscapes of the environment. The present study predicted the seed banks of both soils of alluvial and piedmont zones in different ecological conditions and evaluate the potential of seeds in the restoration of both environments. The composition of the seed bank of soil is mainly affected by the alluvial environment and the structure of cleared area shows that more species of germinating annual grasses and growable seeds with the higher total number. Extant vegetation structures have an important role in the diversity of soil seed reservoirs, whose composition corresponded with the openness of the site. When in situ soil seed bank is recruited, it helps to restore only some components of the plant community in an alluvial environment. In our current research, it was confirmed that seed richness was higher in number at lower elevation (alluvial) than that at high elevation (piedmont). Seed richness showed a significant negative correlation with anions, cations, while significantly positive with altitude that suggests the richness pattern of the overall seed bank of the area is influenced by various environmental factors.


Assuntos
Banco de Sementes , Solo , Ecossistema , Paquistão , Plantas , Poaceae , Sementes
7.
ACS Sens ; 6(12): 4471-4481, 2021 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-34854303

RESUMO

Studies on the dynamics of biological systems and biotechnological processes require measurement techniques that can reveal time dependencies of concentrations of specific biomolecules, preferably with small time delays, short time intervals between subsequent measurements, and the possibility to record over long time spans. For low-concentration biomolecules, these requirements are very challenging since low-concentration assays are typically slow and require new reagents in every assay. Here, we present a sensing methodology that enables rapid monitoring of picomolar and sub-picomolar concentrations in a reversible affinity-based assay, studied using simulations. We demonstrate that low-concentration biomolecules can be monitored with small time delays, short time intervals, and in principle over an endless time span.

8.
Results Phys ; 31: 104917, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34722138

RESUMO

In this manuscript, a new nonlinear model for the rapidly spreading Corona virus disease (COVID-19) is developed. We incorporate an additional class of vaccinated humans which ascertains the impact of vaccination strategy for susceptible humans. A complete mathematical analysis of this model is conducted to predict the dynamics of Corona virus in the population. The analysis proves the effectiveness of vaccination strategy employed and helps public health services to control or to reduce the burden of corona virus pandemic. We first prove the existence and uniqueness and then boundedness and positivity of solutions. Threshold parameter for the vaccination model is computed analytically. Stability of the proposed model at fixed points is investigated analytically with the help of threshold parameter to examine epidemiological relevance of the pandemic. We apply LaSalle's invariance principle from the theory of Lyapunov function to prove the global stability of both the equilibria. Two well known numerical techniques namely Runge-Kutta method of order 4 (RK4), and the Non-Standard Finite Difference (NSFD) method are employed to solve the system of ODE's and to validate our obtained theoretical results. For different coverage levels of voluntary vaccination, we explored a complete quantitative analysis of the model. To draw our conclusions, the effect of proposed vaccination on threshold parameter is studied numerically. It is claimed that Corona virus disease could be eradicated faster if a human community selfishly adopts mandatory vaccination measures at various coverage levels with proper awareness. Finally, we have executed the joint variability of all classes to understand the effect of vaccination strategy on a disease dynamics.

10.
Braz J Biol ; 82: e239219, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33787749

RESUMO

Salmo trutta fario is the most important fish species of family Salmonidae inhibited in cool waters all over the world including the nortern parts of Pakistan. This study was aimed to find out the prey selection and feeding habits of the species. One hundred and eighty five Salmo trutta fario were captured from March 2016 to April 2017. Feeding intensity as represented by a fullness index (FI), changing with various length groups and season. Out of 185 Brown trout 24 fish stomaches were found empty. The most important and common food items of brown trout were Brachycentridae, Blepharocera, Hydropsychidae, ephemerella spp. Kruskal Wallis H-test were applied on feeding intensity groups consisting of three month group. The test statistic for K.W-H-test were (H=8.13 with df =3) had a p-value of 0.043 < (alpha=0.05 indicates favor of the alternative hypothesis of at least one difference among the feeding intensity groups. The linear relationship of N with index of relative importance and %IRI denoted by least square regression line (N = 35.2 + 22.1%IRI), shows that for 22 prey there is 1% change in IRI. The relationship between total length (mm) and fish body weight (gm) is expressed by Pearson correlation coefficient (r = 0.976), showed that total length (mm) and fish body weight (gm.) is highly correlated. Descriptive statistics are used for the stomach fullness, which shows that feeding intensity was recorded higher from March to May. A total of 2289 preys was recorded including the most common were; Trichoptera, Hydropsychidae, Brachycentridae, diptera, blepharocera, ephemerala, chironomida, honey bees, grass hopper, locust, trout egg, trochanter, plant tissue, stones were retrieved from the gut contents of brown trout. According to index of relative importance IRI% four preys represents major components of the diet. The highest IRI% was recorded in Brachycentridae (39.38%), followed by blepharocera (13.23%), Hydropsychidae (10.76%) and ephemerella spp (8.28%). The relationship between IRI and FO is (r =0.556) is moderately correlated with coefficient of determination (r2=0.31). This study will help in the development of an artificial diet for the species for better growth performance in captivity.


Assuntos
Rios , Truta , Animais , Abelhas , Dieta , Hábitos , Paquistão
11.
ACS Nano ; 15(1): 1331-1341, 2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33395272

RESUMO

The biofunctionalization of particles with specific targeting moieties forms the foundation for molecular recognition in biomedical applications such as targeted nanomedicine and particle-based biosensing. To achieve a high precision of targeting for nanomedicine and high precision of sensing for biosensing, it is important to understand the consequences of heterogeneities of particle properties. Here, we present a comprehensive methodology to study with experiments and simulations the collective consequences of particle heterogeneities on multiple length scales, called superpositional heterogeneities, in generating reactivity variability per particle. Single-molecule techniques are used to quantify stochastic, interparticle, and intraparticle variabilities, in order to show how these variabilities collectively contribute to reactivity variability per particle, and how the influence of each contributor changes as a function of the system parameters such as particle interaction area, the particle size, the targeting moiety density, and the number of particles. The results give insights into the consequences of superpositional heterogeneities for the reactivity variability in biomedical applications and give guidelines on how the precision can be optimized in the presence of multiple independent sources of variability.

12.
Nano Lett ; 20(4): 2296-2302, 2020 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-32091908

RESUMO

Single-molecule techniques have become impactful in bioanalytical sciences, though the advantages for continuous biosensing are yet to be discovered. Here we present a multiplexed, continuous biosensing method, enabled by an analyte-sensitive, single-molecular nanoswitch with a particle as a reporter. The nanoswitch opens and closes under the influence of single target molecules. This reversible switching yields binary transitions between two highly reproducible states, enabling reliable quantification of the single-molecule kinetics. The multiplexing functionality is encoded per particle via the dissociation characteristics of the nanoswitch, while the target concentration is revealed by the association characteristics. We demonstrate by experiments and simulations the multiplexed, continuous monitoring of oligonucleotide targets, at picomolar concentrations in buffer and in filtered human blood plasma.


Assuntos
Técnicas Biossensoriais/métodos , Nanoestruturas/química , Oligonucleotídeos/análise , Humanos , Cinética , Nanotecnologia/métodos , Oligonucleotídeos/sangue
13.
Comput Methods Programs Biomed ; 190: 105350, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32078958

RESUMO

Background and Objective The positivity property of the non-linear dynamical systems is one of the essential features in different fields of bio-medical engineering, science and many more. The state variables, involving in the models, describing the natural phenomenon such as concentration, density and population size etc. must be positive. Therefore, the computing techniques used to solve the system of non-linear differential equations must be consisted with the continuous nature of the models. But, unfortunately there are some existing techniques in the literature that do not preserve the positivity property, especially for the multi-space dimensional models. So there is a gap in the literature that should be filled up, by constructing the positivity preserving numerical algorithms. In this study, we consider a susceptible-infected-recovered (SIR) reaction diffusion epidemic model in two space dimensions from biomedical engineering and solved numerically to observe the behavior of the model. Since the state variables involved in this system are population densities therefore we design a novel computational method which is time efficient because of its splitting structure and holds the positivity as well as other important structure of epidemic system. Methods Three different computational techniques are designed to examine the numerical solution of SIR model of infectious disease. Two approaches are well-known existing computing methods named as forward Euler finite difference (FD) method and backward Euler operator splitting finite difference (OS-FD) method. The third approach is operator splitting nonstandard finite difference (OS-NSFD) method which is devised by using the NSFD rules. Results The proposed OS-NSFD technique retains efficiently the stability of equilibria as well as the positivity. Graphical behavior depicts that the existing computing methods can not get success to preserve the structure of the epidemic system of whooping cough dynamics. At the same time OS-NSFD computing method is proven to be reliable and suitable for the system of bio-medical engineering mathematically and graphically. Conclusion A reliable and novel computing technique is developed for the solution of two dimensional reaction diffusion problem. This technique preserves all the imperative characteristics of the model under study. Also the time efficiency of this method makes it easy to find the solution of physical system in two space dimension. The comparison with other techniques shows the efficacy and reliability of the designed technique.


Assuntos
Engenharia Biomédica , Epidemias , Modelos Estatísticos , Coqueluche/epidemiologia , Engenharia Biomédica/estatística & dados numéricos , Epidemias/estatística & dados numéricos , Humanos , Dinâmica não Linear
14.
Sci Rep ; 10(1): 2775, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32066818

RESUMO

This work represents the nature of conduction mechanism in bismuth silicate (BiSiO) nanofibers as a function of temperature and frequency. Scanning electron micrographs and X-rays diffraction patterns exhibited the formation of cubic phases of Bi4(SiO4)3 and Bi12SiO20 nanofibers respectively with an average diameter of ~200 nm. Temperature dependent (300 K-400 K) electrical characterization of fibers was carried out in frequency range of ~20 Hz-2 MHz. The complex impedance analysis showed contribution from bulk and intergranular parts of nanofibers in conduction. Moreover, analysis of the Cole-Cole plot confirmed the space charge dependent behavior of BiSiO nanofibers. Two types of relaxation phenomena were observed through Modulus analysis. In ac conductivity curve, step like feature of plateau and dispersive regions were described by Maxwell-Wagner effect while the dc part obeyed the Arrhenius law. However, frequency dependent ac conductivity revealed the presence of conduction mechanism in diverse regions that was ascribed to large polaron tunneling model. Detailed analysis of complex Impedance and ac conductivity measurement showed negative temperature coefficient of resistance for the BiSiO nanofibers. Current-voltage (IV) characteristics represented ohmic conduction; followed by space charge limited current conduction at intermediate voltages. Results from both ac and dc measurements were in good agreement with each other.

15.
Chaos ; 29(10): 103101, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31675795

RESUMO

In this work, we investigate the numerical solution of the susceptible exposed infected and recovered measles epidemic model. We also evaluate the numerical stability and the bifurcation value of the transmission parameter from susceptibility to a disease of the proposed epidemic model. The proposed method is a chaos free finite difference scheme, which also preserves the positivity of the solution of the given epidemic model.


Assuntos
Epidemias , Sarampo/epidemiologia , Modelos Biológicos , Suscetibilidade a Doenças , Humanos , Dinâmica Populacional
16.
ACS Omega ; 4(1): 2030-2039, 2019 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-31459454

RESUMO

Orthorhombic phase bismuth sulfide (Bi2S3) nanobelts were prepared via  liquid-solid phase reaction method. Bi2S3 nanobelts were observed to be preferentially oriented along the (101) plane. Direct band gap (2.95 eV) and characteristic wavelength (λmax = 342 nm) were extracted through UV-visible spectroscopy. Specific surface area (9.8 m2/g) and pore size (2.5-120 nm) were evaluated through Brunauer-Emmett-Teller (BET) analysis. Relative humidity (RH) sensing properties were studied in the range of 11-97% RH at ambient conditions. The response of the sensor increases linearly with increase in RH. Fast response time (8-10 s) and recovery time (15 s) were observed. Reproducible and large response was also observed between 11 and 97% RH. Small hysteresis (<5%) and long-term stability during 30 days were confirmed. As a function of frequency, capacitance, alternating current conductivity, and electrical complex modulus in the frequency range of 20-2 MHz were studied at 11-97% RH. The sensing mechanism was also studied.

17.
Heliyon ; 4(5): e00631, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29872764

RESUMO

This work is concerned with the numerical modeling of susceptible-latent-breakingout-quarantine-susceptible (SLBQRS) computer virus dynamics. The SLBQRS epidemic system is solved with three finite difference methods, one is proposed nonstandard finite difference (NSFD) method and the other two are well known forward Euler finite difference (FD) method and Runge-Kutta finite difference method of order 4 (RK-4). The proposed NSFD method preserves all the essential conditions of the continuous system while RK-4 method and forward Euler method fail to preserve some of its essential conditions like positivity, convergence to the true steady states of the continuous system. The convergence analysis of the proposed NSFD method is also performed. Bifurcation value of infection coefficient for the system is also find out.

18.
J Appl Microbiol ; 125(2): 457-467, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29729069

RESUMO

AIM: Thiss study was conducted to investigate the possible role of a compatible solute from radio-halophilic bacterium against desiccation and ultra-violet radiation-induced oxidative stress. METHODS AND RESULTS: Nine different radio-resistant bacteria were isolated from desert soil, where strain WMA-LM19 was chosen for detailed studies on the basis of its high tolerance to ultraviolet radiation among all these isolates. Here, 16S rRNA gene sequencing indicated the bacterium was closely related to Stenotrophomonas sp. (KT008383). A bacterial milking strategy was applied for extraction of intracellular compatible solutes in 70% (v/v) ethanol, which were purified by High Performance Liquid Chromatography (HPLC). The compound was characterized as ectoine by 1 H and 13 C Nuclear Magnetic Resonance (NMR), and Mass Spectrometry (MS). Ectoine inhibited oxidative damage to proteins and lipids in comparison to the standard ascorbic acid. It also demonstrated more efficient prevention (54·80%) against lysis to erythrocytes membrane by surface active agents than lecithin. Furthermore, a high level of ectoine-mediated protection of bovine serum albumin against ionizing radiation (1 500-2 000Jm-2 ) was observed, as indicated by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) analysis. CONCLUSION: The results indicated that ectoine from Stenotrophomonas sp. WMA-LM19 can be used as a potential mitigator and radio-protective agent to overcome radiation- and salinity-mediated oxidative damages in extreme environment. SIGNIFICANCE AND IMPACT OF THE STUDY: Due to its anti-oxidant properties, ectoine from a radio-halophilic bacterium might be used in sunscreen formulation for protection against UV-induced oxidative stress.


Assuntos
Diamino Aminoácidos/farmacologia , Protetores contra Radiação/farmacologia , Stenotrophomonas/química , Raios Ultravioleta/efeitos adversos , Animais , Membrana Eritrocítica/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Microbiologia do Solo , Stenotrophomonas/genética
19.
Mol Psychiatry ; 23(4): 973-984, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28397838

RESUMO

Approximately 1% of the global population is affected by intellectual disability (ID), and the majority receive no molecular diagnosis. Previous studies have indicated high levels of genetic heterogeneity, with estimates of more than 2500 autosomal ID genes, the majority of which are autosomal recessive (AR). Here, we combined microarray genotyping, homozygosity-by-descent (HBD) mapping, copy number variation (CNV) analysis, and whole exome sequencing (WES) to identify disease genes/mutations in 192 multiplex Pakistani and Iranian consanguineous families with non-syndromic ID. We identified definite or candidate mutations (or CNVs) in 51% of families in 72 different genes, including 26 not previously reported for ARID. The new ARID genes include nine with loss-of-function mutations (ABI2, MAPK8, MPDZ, PIDD1, SLAIN1, TBC1D23, TRAPPC6B, UBA7 and USP44), and missense mutations include the first reports of variants in BDNF or TET1 associated with ID. The genes identified also showed overlap with de novo gene sets for other neuropsychiatric disorders. Transcriptional studies showed prominent expression in the prenatal brain. The high yield of AR mutations for ID indicated that this approach has excellent clinical potential and should inform clinical diagnostics, including clinical whole exome and genome sequencing, for populations in which consanguinity is common. As with other AR disorders, the relevance will also apply to outbred populations.


Assuntos
Consanguinidade , Deficiência Intelectual/genética , Adulto , Mapeamento Cromossômico/métodos , Variações do Número de Cópias de DNA , Família , Feminino , Genes Recessivos , Heterogeneidade Genética , Homozigoto , Humanos , Deficiência Intelectual/metabolismo , Irã (Geográfico) , Mutação com Perda de Função , Masculino , Análise em Microsséries/métodos , Pessoa de Meia-Idade , Mutação , Paquistão , Linhagem , Sequenciamento Completo do Exoma/métodos
20.
Saudi J Anaesth ; 10(4): 453-455, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27833494

RESUMO

Sanjad-Sakati syndrome is an autosomal recessive genetic disorder first described in Saudi Arabia. Anesthetic management of these patients is challenging due to airway difficulties, electrolyte imbalance, growth and mental retardation, and seizures. The anesthetic management of the syndrome is described in this case report.

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