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1.
Nature ; 607(7917): 48-51, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35794268

RESUMO

How quasars powered by supermassive black holes formed less than a billion years after the Big Bang is still one of the outstanding problems in astrophysics, 20 years after their discovery1-4. Cosmological simulations suggest that rare cold flows converging on primordial haloes in low-shear environments could have created these quasars if they were 104-105 solar masses at birth, but could not resolve their formation5-8. Semi-analytical studies of the progenitor halo of a primordial quasar found that it favours the formation of such seeds, but could not verify if one actually appeared9. Here we show that a halo at the rare convergence of strong, cold accretion flows creates massive black holes seeds without the need for ultraviolet backgrounds, supersonic streaming motions or even atomic cooling. Cold flows drive violent, supersonic turbulence in the halo, which prevents star formation until it reaches a mass that triggers sudden, catastrophic baryon collapse that forms 31,000 and 40,000 solar-mass stars. This simple, robust process ensures that haloes capable of forming quasars by a redshift of z > 6 produce massive seeds. The first quasars were thus a natural consequence of structure formation in cold dark matter cosmologies, and not exotic, finely tuned environments as previously thought10-14.

2.
World J Surg ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39030768

RESUMO

BACKGROUND: Healthcare systems contribute 5%-10% of the global carbon footprint. Given the detrimental impact of climate change on population health, health systems must seek to address this environmental responsibility. This is especially relevant in the modern era of minimally invasive procedures (MIP) where single-use instruments are increasingly popular. We compared the environmental footprint of single-use versus multi-use instruments in MIP. METHODS: We conducted a systematic review across five databases to identify relevant original studies, following the PRISMA guidelines. We extracted environmental impact data and performed a quality assessment of included studies. RESULTS: We included 13 studies published between 2005 and 2024. Eight employed Life Cycle Analysis (LCAs), which is the gold standard methodology for studies evaluating environmental impact. The instruments studied included laparoscopy systems, endoscopes, cystoscopes, bronchoscopes, duodenoscopes, and ureteroscopes. Six studies, including three high quality LCAs and one fair quality LCA, showed that single-use instruments have a significantly higher environmental footprint than their multi-use counterparts. Six studies suggested a lower environmental footprint for single-use instruments, and one study presented comparable results. However, these studies were of poor/fair quality. CONCLUSION: Although our systematic review yielded mixed results, all high quality LCAs suggested multi-use instruments may be more environmentally friendly than their single-use counterparts. Our findings are limited by inter-study heterogeneity and methodological quality. There is an urgent need for additional research employing gold standard methodologies to explore the interplay between environmental impact and operational factors such as workflow efficiency and cost-benefit ratio to allow health systems to make more informed decisions.

3.
J Phys Chem A ; 127(16): 3570-3576, 2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37058573

RESUMO

Structures of platinum oxide cluster cations (PtnOm+) were studied by ion mobility-mass spectrometry in combination with theoretical calculations. Structures of oxygen-equivalent PtnOn+ (n = 3-7) clusters were discussed from the comparison between their collision cross sections (CCSs) obtained by mobility measurement and simulated CCSs of their structural candidates from structural optimization calculations. Assigned structures of PtnOn+ were found to be composed of Pt frameworks and bridging O atoms, which follows the previous theoretical prediction on the neutral clusters. The structures change from planar (n = 3 and 4) to three-dimensional (n = 5-7) with increasing cluster size by deforming platinum frameworks. Comparison with other group-10 metal oxide cluster cations (MnOn+; M = Ni and Pd) showed that the PtnOn+ structures have a similar tendency to PdnOn+ rather than NinOn+.

4.
BMC Surg ; 23(1): 348, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37974149

RESUMO

Climate change has far-reaching repercussions for surgical healthcare in low- and middle-income countries. Natural disasters cause injuries and infrastructural damage, while air pollution and global warming may increase surgical disease and predispose to worse outcomes. Socioeconomic ramifications further strain healthcare systems, highlighting the need for integrated climate and healthcare policies.


Assuntos
Poluição do Ar , Mudança Climática , Humanos , Países em Desenvolvimento
5.
Can J Infect Dis Med Microbiol ; 2020: 1597839, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32849932

RESUMO

BACKGROUND: To describe our experience with the use of Elvitegravir/Cobicistat/Emtricitabine/Tenofovir Alafenamide (EVG/COBI/FTC/TAF) in the treatment of HIV-infected patients in Qatar including both naïve and treatment experienced. We also report the reasons for switching to EVG/COBI/FTC/TAF in treatment-experienced patients, response to treatment, and tolerability. METHOD: Review of the medical records of the first 100 HIV-infected patients treated with EVG/COBI/FTC/TAF. RESULTS: Among the 100 HIV-infected patients who were treated with EVG/COBI/FTC/TAF, 64 were Qatari and the rest were from other nationalities. 80 patients were males and 20 were females. 29 were treatment naïve, and 71 were treatment experienced. Among treatment-experienced patients, the most common reasons for switch to EVG/COBI/FTC/TAF were safety concerns, followed by regimen simplification and adverse drug reaction of the previous regimen (40%, 14%, and 13%, respectively). Treatment response to EVG/COBI/FTC/TAF leading to undetectable viral load in naïve patients was 69%, and in treatment-experienced patients, it was 83% with an overall response among all patients of 79%. Excluding those who left the country and whose data were not available, the response rate will be 86%. Tolerability was excellent with mild side effects and no discontinuation due to side effects. CONCLUSION: Experience with the use of EVG/COBI/FTC/TAF in 100 patients with HIV infection in Qatar was favourable both in treatment naïve patients and in those who were treatment experienced with an excellent tolerability.

6.
J Helminthol ; 92(2): 142-153, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28382873

RESUMO

The potential therapeutic value of Moringa oleifera extract (MOE), due to its anti-inflammatory and anti-oxidant effects, has been reported previously. In this study, Hymenolepis nana antigen (HNA) in combination with MOE was used in immunization against H. nana infection. Adult worm and egg counts were taken, while histological changes in the intestine were observed. Mucosal mast (MMCs) and goblet cells (GCs) were stained with specific stains, while serum and intestinal IgA were assayed using enzyme-linked immunosorbent assay (ELISA). Reduced glutathione (GSH) and lipid peroxidation (thiobarbituric acid reactive substances, TBARS) were assayed. Real-time polymerase chain reaction (PCR) was used for detection of mRNA expression in ileum tissue. The results demonstrated an improvement in the architecture of intestinal villi, decreased inducible nitric oxide synthase (iNOs) and TBARS, and increased GSH in HNA, MOE and MOE + HNA groups. In the same groups, an increase in GCs, mucin 2 (MUC2), interleukins (IL)-4, -5 and -9, and stem cell factor (SCF) versus a decrease in both interferon-gamma (IFN-γ) and transforming growth factor (TGF-ß) expression appeared. HNA and MOE + HNA increased serum and intestinal IgA, respectively. MOE decreased MMCs and achieved the highest reductions in both adult worms and eggs. In conclusion, MOE could achieve protection against H. nana infections through decreased TGF-ß, IFN-γ and MMC counts versus increased GC counts, T-helper cell type 2 (Th2) cytokines and IgA level.


Assuntos
Himenolepíase/tratamento farmacológico , Hymenolepis/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Intestinos/imunologia , Moringa oleifera/química , Extratos Vegetais/uso terapêutico , Animais , Anti-Helmínticos/administração & dosagem , Anti-Helmínticos/química , Anti-Helmínticos/uso terapêutico , Citocinas/efeitos dos fármacos , Citocinas/imunologia , Glutationa/análise , Himenolepíase/imunologia , Himenolepíase/parasitologia , Imunoglobulina A/análise , Imunoglobulina A/imunologia , Interferon gama/efeitos dos fármacos , Interferon gama/genética , Interferon gama/imunologia , Intestinos/parasitologia , Peroxidação de Lipídeos , Camundongos , Óxido Nítrico Sintase/efeitos dos fármacos , Óxido Nítrico Sintase/genética , Contagem de Ovos de Parasitas , Extratos Vegetais/administração & dosagem , Células Th2/efeitos dos fármacos , Células Th2/imunologia
7.
Clin Exp Immunol ; 190(1): 110-121, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28640379

RESUMO

One of the most widespread and effective environmental factors is the infection with enteroviruses (EVs) which accelerate ß cell destruction in type 1 diabetes (T1D). This study represented a comparison between diabetic EV+ and EV- children as well as correlation analysis between autoantibodies, T1D markers, cytokines, complement activation products and anti-coxsackievirus (CV) immunoglobulin (Ig)G. EV RNA was detected in Egyptian children with T1D (26·2%) and healthy controls (0%). Detection of anti-CV IgG in T1D-EV+ resulted in 64% positivity. Within T1D-EV+ , previously diagnosed (PD) showed 74 versus 56% in newly diagnosed (ND) children. Comparisons between populations showed increased levels of haemoglobin A1c (HbA1c), C-reactive protein (CRP), nitric oxide (NO), glutamic acid decarboxylase and insulin and islet cell autoantibodies [glutamic acid decarboxylase autoantibodies (GADA), insulin autoantibodies (IAA) and islet cell cytoplasmic autoantibodies (ICA), respectively], interferon (IFN)-γ, tumour necrosis factor (TNF)-α, interleukin (IL)-1ß, IL -10, IL -12, IL -17, C3d and sC5-9 in T1D-EV+ versus T1D-EV- . Conversely, both IL-20 and transforming growth factor (TGF-ß) decreased in T1D-EV+ versus EV- , while IL-4, -6 and -13 did not show any changes. Correlation analysis showed dependency of accelerated autoimmunity and ß cell destruction on increased IFN-γ, IL-12 and IL-17 versus decreased IL-4, -6 and -13. In conclusion, IFN-γ, IL-12 and IL-17 played an essential role in exacerbating EV+ -T1D, while C3d, sC5b -9, IL-10 and -20 displayed distinct patterns.


Assuntos
Citocinas/metabolismo , Diabetes Mellitus Tipo 1/imunologia , Infecções por Enterovirus/imunologia , Enterovirus/imunologia , Ilhotas Pancreáticas/imunologia , Adolescente , Anticorpos Antivirais/metabolismo , Apoptose , Autoanticorpos/metabolismo , Criança , Pré-Escolar , Ativação do Complemento , Complemento C3d/metabolismo , Complemento C5b/metabolismo , Citocinas/genética , Diabetes Mellitus Tipo 1/complicações , Egito , Infecções por Enterovirus/complicações , Glutamato Descarboxilase/imunologia , Humanos , Insulina/imunologia , Ilhotas Pancreáticas/patologia
8.
Scand J Immunol ; 86(2): 83-90, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28513991

RESUMO

Hymenolepis nana is the most commonly known intestinal cestode infecting mainly human. This study aimed to investigate the potential effect of chitosan particles (CSP) to enhance the immune system against H. nana infection. Determination of worm burden, egg output, histopathological changes, oxidative stress markers (lipid peroxidation and reduced glutathione), goblet (GCs) and mucosal mast cells (MMCs) counts in intestinal ileum was performed. In addition, levels of intestinal mRNA expression of interleukin (IL)-4, IL-9, stem cell factor (SCF), type I and II interferons (IFN)-α/ γ, tumour necrosis factor (TNF)-α, mucin 2 (MUC2) and inducible nitric oxide synthase (iNOs) were investigated using real-time PCR. The results indicated induced reductions in adult worm and egg counts in infected mice after CSP treatment. This was associated with improvement in tissue morphometric measurements and oxidative stress which were altered after infection. Expression levels of iNOs, IFN-α, IFN-γ, TNF-α and IL-9 were decreased by CSP. Conversely, expression levels of MUC2, IL-4 and SCF increased compared to infected untreated group. In addition, GCs and MMCs counts were normalized by CSP. In conclusion, this study could indicate the immunoprotective effect of CSP against H. nana infection. This was characterized with Th2 anti-inflammatory responses.


Assuntos
Quitosana/farmacologia , Himenolepíase/prevenção & controle , Hymenolepis nana/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Animais , Quitosana/química , Quitosana/imunologia , Citocinas/genética , Citocinas/imunologia , Citocinas/metabolismo , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/imunologia , Proteínas de Helminto/genética , Proteínas de Helminto/imunologia , Proteínas de Helminto/metabolismo , Interações Hospedeiro-Parasita/efeitos dos fármacos , Interações Hospedeiro-Parasita/imunologia , Humanos , Himenolepíase/imunologia , Himenolepíase/parasitologia , Hymenolepis nana/imunologia , Hymenolepis nana/fisiologia , Interferon-alfa/genética , Interferon-alfa/imunologia , Interferon-alfa/metabolismo , Interferon gama/genética , Interferon gama/imunologia , Interferon gama/metabolismo , Interleucina-4/genética , Interleucina-4/imunologia , Interleucina-4/metabolismo , Intestinos/imunologia , Intestinos/parasitologia , Camundongos , Mucina-2/genética , Mucina-2/imunologia , Mucina-2/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/imunologia , Óxido Nítrico Sintase Tipo II/metabolismo , Contagem de Ovos de Parasitas , Tamanho da Partícula , Substâncias Protetoras/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/metabolismo
9.
Crit Rev Biotechnol ; 36(2): 353-67, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25394538

RESUMO

Rice blast disease, which is caused by the fungal pathogen Magnaporthe oryzae, is a recurring problem in all rice-growing regions of the world. The use of resistance (R) genes in rice improvement breeding programmes has been considered to be one of the best options for crop protection and blast management. Alternatively, quantitative resistance conferred by quantitative trait loci (QTLs) is also a valuable resource for the improvement of rice disease resistance. In the past, intensive efforts have been made to identify major R-genes as well as QTLs for blast disease using molecular techniques. A review of bibliographic references shows over 100 blast resistance genes and a larger number of QTLs (∼500) that were mapped to the rice genome. Of the blast resistance genes, identified in different genotypes of rice, ∼22 have been cloned and characterized at the molecular level. In this review, we have summarized the reported rice blast resistance genes and QTLs for utilization in future molecular breeding programmes to introgress high-degree resistance or to pyramid R-genes in commercial cultivars that are susceptible to M. oryzae. The goal of this review is to provide an overview of the significant studies in order to update our understanding of the molecular progress on rice and M. oryzae. This information will assist rice breeders to improve the resistance to rice blast using marker-assisted selection which continues to be a priority for rice-breeding programmes.


Assuntos
Mapeamento Cromossômico , Clonagem Molecular , Resistência à Doença/genética , Genes de Plantas/genética , Magnaporthe/patogenicidade , Oryza , Oryza/genética , Oryza/microbiologia , Oryza/fisiologia , Proteínas de Plantas/genética
10.
Crit Rev Biotechnol ; 36(1): 165-74, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25198435

RESUMO

The blast fungus, Magnaporthe oryzae, causes serious disease on a wide variety of grasses including rice, wheat and barley. The recognition of pathogens is an amazing ability of plants including strategies for displacing virulence effectors through the adaption of both conserved and variable pathogen elicitors. The pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) and effector-triggered immunity (ETI) were reported as two main innate immune responses in plants, where PTI gives basal resistance and ETI confers durable resistance. The PTI consists of extracellular surface receptors that are able to recognize PAMPs. PAMPs detect microbial features such as fungal chitin that complete a vital function during the organism's life. In contrast, ETI is mediated by intracellular receptor molecules containing nucleotide-binding (NB) and leucine rich repeat (LRR) domains that specifically recognize effector proteins produced by the pathogen. To enhance crop resistance, understanding the host resistance mechanisms against pathogen infection strategies and having a deeper knowledge of innate immunity system are essential. This review summarizes the recent advances on the molecular mechanism of innate immunity systems of rice against M. oryzae. The discussion will be centered on the latest success reported in plant-pathogen interactions and integrated defense responses in rice.


Assuntos
Interações Hospedeiro-Patógeno/imunologia , Magnaporthe/patogenicidade , Oryza/imunologia , Imunidade Vegetal/genética , Quitina/genética , Quitina/imunologia , Magnaporthe/imunologia , Oryza/crescimento & desenvolvimento , Oryza/microbiologia , Moléculas com Motivos Associados a Patógenos/imunologia
11.
Epidemiol Infect ; 144(8): 1612-21, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26626237

RESUMO

Linked administrative population data were used to estimate the burden of childhood respiratory syncytial virus (RSV) hospitalization in an Australian cohort aged <5 years. RSV-coded hospitalizations data were extracted for all children aged <5 years born in New South Wales (NSW), Australia between 2001 and 2010. Incidence was calculated as the total number of new episodes of RSV hospitalization divided by the child-years at risk. Mean cost per episode of RSV hospitalization was estimated using public hospital cost weights. The cohort comprised of 870 314 children. The population-based incidence/1000 child-years of RSV hospitalization for children aged <5 years was 4·9 with a rate of 25·6 in children aged <3 months. The incidence of RSV hospitalization (per 1000 child-years) was 11·0 for Indigenous children, 81·5 for children with bronchopulmonary dysplasia (BPD), 10·2 for preterm children with gestational age (GA) 32-36 weeks, 27·0 for children with GA 28-31 weeks, 39·0 for children with GA <28 weeks and 6·7 for term children with low birthweight. RSV hospitalization was associated with an average annual cost of more than AUD 9 million in NSW. RSV was associated with a substantial burden of childhood hospitalization specifically in children aged <3 months and in Indigenous children and children born preterm or with BPD.


Assuntos
Hospitalização/economia , Infecções por Vírus Respiratório Sincicial/epidemiologia , Infecções por Vírus Respiratório Sincicial/patologia , Vírus Sinciciais Respiratórios/isolamento & purificação , Pré-Escolar , Feminino , Custos de Cuidados de Saúde , Humanos , Incidência , Lactente , Recém-Nascido , Armazenamento e Recuperação da Informação , Masculino , New South Wales/epidemiologia , Estudos Retrospectivos
12.
Dis Esophagus ; 29(8): 1002-1006, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26354288

RESUMO

Gastrocolic reflux is a troublesome symptom causing repeated aspiration or chocking in patients underwent retrosternal colon interposition. Various techniques were described to avoid such complication, however, they entail complicated technique that may jeopardize the viability of the graft or cause obstructing symptoms. A simple antireflux procedure is described here alleviating this problem. Over the last 7 years, 87 patients had gastrocolic antireflux procedure for cologastric anastomosis; 75 patients as a primary procedure (group 1) and 12 patients as a secondary procedure treating symptomatic reflux (group 2). The technique entails the creation of cologastric angle after finishing the cologastric anastomosis by applying three stitches between the colon and the stomach, thus tucking the colon to the stomach for 3-4 cm. Gastrocolic reflux was evaluated clinically and radiologically 3 months postoperatively. In group 1, three cases (4%) suffered symptomatic gastrocolic reflux, and seven cases (9.3%) had radiological asymptomatic mild reflux, while all patients in group 2 had complete alleviation of their symptoms with gastrogram showing no reflux. Gastrocolic reflux can be treated simply by creation of cologastric angle; however, controlled trial is needed to confirm its effectiveness in comparison to other described techniques.


Assuntos
Anastomose Cirúrgica/métodos , Colo/transplante , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Atresia Esofágica/cirurgia , Estenose Esofágica/cirurgia , Refluxo Gastroesofágico/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Estômago/cirurgia , Queimaduras Químicas/etiologia , Queimaduras Químicas/cirurgia , Cáusticos/toxicidade , Criança , Pré-Escolar , Estenose Esofágica/induzido quimicamente , Feminino , Refluxo Gastroesofágico/cirurgia , Humanos , Lactente , Masculino , Complicações Pós-Operatórias/cirurgia
13.
Plant Dis ; 100(10): 2025-2033, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30683013

RESUMO

The pathogenicity of 331 blast isolates (Pyricularia oryzae Cavara) collected from different regions and ecosystems for rice cultivation in Bangladesh was evaluated by compatibility on 23 differential varieties (DV), each harboring a single blast resistance gene, and susceptible 'Lijiangxintuanheigu' (LTH). A wide variation in virulence was found among the isolates, and 267 races were classified using a new designation system. Virulence of blast isolates against DV carrying the resistance genes Pia, Pib, Pit, Pik-s, Piz-t, Pi12(t), Pi19(t), and Pi20(t), as well as avirulence against those carrying Pish, Pi9, Pita-2, and Pita, was distributed widely in Bangladesh. Cluster analysis of the compatibility data on the DV initially classified the isolates into groups I and II. The virulence spectra of the two groups differed mainly according to the reactions of the DV to Pii, Pi3, Pi5(t), Pik-m, Pi1, Pik-h, Pik, Pik-p, and Pi7(t). Group I isolates were distributed mainly in rainfed lowlands, whereas group II isolates were found mainly in irrigated lowlands; however, there were no critical differences in geographic distribution of the blast isolates. In total, 26 isolates, which could be used to identify the 23 resistance genes of the DV on the basis of their reaction patterns, were selected as a set of standard differential blast isolates. To our knowledge, this is the first clear demonstration of the diversity and differentiation of blast races in Bangladesh. This information will be used to develop a durable blast protection system in that country.

14.
ScientificWorldJournal ; 2016: 2186069, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27747271

RESUMO

Arsenic pollution became a great problem in the recent past in different countries including Bangladesh. The microlevel studies were conducted to see the spatial variation of arsenic in soils and plant parts contaminated through ground water irrigation. The study was performed in shallow tube well command areas in Sadar Upazila (subdistrict), Faridpur, Bangladesh, where both soil and irrigation water arsenic are high. Semivariogram models were computed to determine the spatial dependency of soil, water, grain, straw, and husk arsenic (As). An arsenic concentration surface was created spatially to describe the distribution of arsenic in soil, water, grain, straw, and husk. Command area map was digitized using Arcview GIS from the "mouza" map. Both arsenic contaminated irrigation water and the soils were responsible for accumulation of arsenic in rice straw, husk, and grain. The accumulation of arsenic was higher in water followed by soil, straw, husk, and grain. Arsenic concentration varied widely within command areas. The extent and propensity of arsenic concentration were higher in areas where high concentration of arsenic existed in groundwater and soils. Spherical model was a relatively better and appropriate model. Kriging method appeared to be more suitable in creating interpolated surface. The average arsenic content in grain was 0.08-0.45 mg/kg while in groundwater arsenic level it ranged from 138.0 to 191.3 ppb.


Assuntos
Arsênio/análise , Oryza/química , Poluentes do Solo/análise , Poluentes Químicos da Água/análise , Irrigação Agrícola , Bangladesh , Monitoramento Ambiental , Contaminação de Alimentos , Água Subterrânea/química , Análise Espacial
15.
J Environ Sci (China) ; 43: 26-39, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27155406

RESUMO

Highly active mesoporous TiO2 of about 6nm crystal size and 280.7m(2)/g specific surface areas has been successfully synthesized via controlled hydrolysis of titanium butoxide at acidic medium. It was characterized by means of XRD (X-ray diffraction), SEM (scanning electron microscopy), TEM (transmission electron microscopy), FT-IR (Fourier transform infrared spectroscopy), TGA (thermogravimetric analysis), DSC (differential scanning calorimetry) and BET (Brunauer-Emmett-Teller) surface area. The degradation of dichlorophenol-indophenol (DCPIP) under ultraviolet (UV) light was studied to evaluate the photocatalytic activity of samples. The effects of different parameters and kinetics were investigated. Accordingly, a complete degradation of DCPIP dye was achieved by applying the optimal operational conditions of 1g/L of catalyst, 10mg/L of DCPIP, pH of 3 and the temperature at 25±3°C after 3min under UV irradiation. Meanwhile, the Langmuir-Hinshelwood kinetic model described the variations in pure photocatalytic branch in consistent with a first order power law model. The results proved that the prepared TiO2 nanoparticle has a photocatalytic activity significantly better than Degussa P-25.


Assuntos
2,6-Dicloroindofenol/química , Nanopartículas/química , Processos Fotoquímicos , Titânio/química , Cinética , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Modelos Químicos , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
16.
Genet Mol Res ; 14(4): 17007-18, 2015 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-26681048

RESUMO

Disease susceptibility and genetic variability in 10 eggplant genotypes were studied after inoculating Phomopsis vexans under confined field conditions. Random amplified polymorphic DNA (RAPD) markers were used to assess genetic variation and relationships among eggplant genotypes. The disease index of leaves ranged 0.208-13.79%, while fruit infection ranged 2.15-42.76%. Two varieties, Dohazari G and Laffa S, were found to be susceptible, 6 were moderately resistant, 1 was moderately susceptible, and BAU Begun-1 was resistant to P. vexans. Amplification of genomic DNA by using 3 RAPD primers produced 20 bands: 14 (70%) were polymorphic and 6 (30%) were monomorphic. The highest intra-variety similarity indices values were found in ISD 006, Ishurdi L, Jessore L, and BAU Begun-1 (100%), while the lowest was in Dohazari G (90%). The lowest genetic distance (0.0513) and the highest genetic identity (0.9500) were observed between the ISD 006 and Ishurdi L combinations. A comparatively higher genetic distance (0.3724) and the lowest genetic identity (0.6891) were observed between the ISD 006 and Dohazari G combinations. A dendogram was constructed based on Nei's genetic distance, which produced 2 main clusters of the genotypes - Cluster I: ISD 006, Ishurdi L, Marich begun L, BAU Begun-1, Marich begun S, and Chega and Cluster 2: Laffa S, Dohazari G, Jessore L, and Singhnath. Genetic variation and its relationship with disease susceptibility were assessed using RAPD markers, to develop disease-resistant varieties and improve eggplant crops.


Assuntos
Marcadores Genéticos , Predisposição Genética para Doença , Variação Genética , Doenças das Plantas/genética , Solanum melongena/genética , Ascomicetos , Resistência à Doença/genética , Evolução Molecular , Filogenia , Doenças das Plantas/microbiologia , Reação em Cadeia da Polimerase , Técnica de Amplificação ao Acaso de DNA Polimórfico , Solanum melongena/classificação
17.
Genet Mol Res ; 14(4): 18140-52, 2015 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-26782461

RESUMO

To examine the impact of regional and seasonal variations on the incidence and severity of sheath rot, a major seed-borne disease of rice caused by Sarocladium oryzae, data on incidence and severity were collected from 27 selected fields in the Gazipur, Rangpur, Bogra, Chittagong, Comilla, Gopalgonj, Jessore, Manikgonj, and Bhola districts of Bangladesh in rain-fed and irrigated conditions. Cultural variability of 29 pathogen isolates obtained from 8 different locations was studied on potato dextrose agar (PDA) and genetic variability was determined by DNA fingerprinting using variable number tandem repeat-polymerase chain reaction markers. Overall, disease incidence and severity were higher in irrigated rice. Disease incidence and severity were highest in the Bhola district in rain-fed rice and lowest in irrigated rice. Mycelial growth of 29 representative isolates was found to vary on PDA and the isolates were divided into 6 groups. The range of the overall size of conidia of the selected isolates was 2.40-7.20 x 1.20-2.40 µm. Analysis of the DNA fingerprint types of the 29 isolates of S. oryzae, obtained from the amplification reactions, revealed 10 fingerprinting types (FPTs) that were 80% similar. FPT-1 was the largest group and included 13 isolates (44.8%), while FPT-2 was the third largest group and included 3 isolates. Each of FPT-3, 4, 5, and 6 included only 1 isolate. We observed no relationship between cultural and genetic groupings.


Assuntos
Genética Populacional , Hypocreales/genética , Oryza/microbiologia , Doenças das Plantas/genética , Impressões Digitais de DNA/métodos , Ecologia , Variação Genética , Interações Hospedeiro-Patógeno/genética , Hypocreales/patogenicidade , Oryza/genética , Doenças das Plantas/microbiologia , Sementes/genética , Sementes/microbiologia
18.
Public Health ; 185: 95-96, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32593054
19.
Mol Biol Rep ; 41(11): 7395-411, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25085039

RESUMO

Common purslane (Portulaca oleracea), also known as pigweed, fatweed, pusle, and little hogweed, is an annual succulent herb in the family Portulacaceae that is found in most corners of the globe. From the ancient ages purslane has been treated as a major weed of vegetables as well as other crops. However, worldwide researchers and nutritionists have studied this plant as a potential vegetable crop for humans as well as animals. Purslane is a nutritious vegetable with high antioxidant properties and recently has been recognized as the richest source of α-linolenic acid, essential omega-3 and 6 fatty acids, ascorbic acid, glutathione, α-tocopherol and ß-carotene. The lack of vegetable sources of ω-3 fatty acids has resulted in a growing level of attention to introduce purslane as a new cultivated vegetable. In the rapid-revolutionizing worldwide atmosphere, the ability to produce improved planting material appropriate to diverse and varying rising conditions is a supreme precedence. Though various published reports on morphological, physiological, nutritional and medicinal aspects of purslane are available, research on the genetic improvement of this promising vegetable crop are scant. Now it is necessary to conduct research for the genetic improvement of this plant. Genetic improvement of purslane is also a real scientific challenge. Scientific modernization of conventional breeding with the advent of advance biotechnological and molecular approaches such as tissue culture, protoplast fusion, genetic transformation, somatic hybridization, marker-assisted selection, qualitative trait locus mapping, genomics, informatics and various statistical representation have opened up new opportunities of revising the relationship between genetic diversity, agronomic performance and response to breeding for varietal improvement. This review is an attempt to amalgamate the assorted scientific information on purslane propagation, cultivation, varietal improvement, nutrient analyses, medicinal uses and to describe prospective research especially for genetic improvement of this crop.


Assuntos
Agricultura/métodos , Cruzamento/métodos , Produtos Agrícolas , Engenharia Genética/métodos , Valor Nutritivo/genética , Portulaca/crescimento & desenvolvimento , Portulaca/genética , Ácidos Graxos Ômega-3/análise , Engenharia Genética/tendências , Portulaca/química
20.
Nature ; 453(7191): 84-8, 2008 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-18451859

RESUMO

The climate of the North Atlantic region exhibits fluctuations on decadal timescales that have large societal consequences. Prominent examples include hurricane activity in the Atlantic, and surface-temperature and rainfall variations over North America, Europe and northern Africa. Although these multidecadal variations are potentially predictable if the current state of the ocean is known, the lack of subsurface ocean observations that constrain this state has been a limiting factor for realizing the full skill potential of such predictions. Here we apply a simple approach-that uses only sea surface temperature (SST) observations-to partly overcome this difficulty and perform retrospective decadal predictions with a climate model. Skill is improved significantly relative to predictions made with incomplete knowledge of the ocean state, particularly in the North Atlantic and tropical Pacific oceans. Thus these results point towards the possibility of routine decadal climate predictions. Using this method, and by considering both internal natural climate variations and projected future anthropogenic forcing, we make the following forecast: over the next decade, the current Atlantic meridional overturning circulation will weaken to its long-term mean; moreover, North Atlantic SST and European and North American surface temperatures will cool slightly, whereas tropical Pacific SST will remain almost unchanged. Our results suggest that global surface temperature may not increase over the next decade, as natural climate variations in the North Atlantic and tropical Pacific temporarily offset the projected anthropogenic warming.

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