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1.
Plant Dis ; 107(8): 2490-2499, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36750719

RESUMO

Black root rot complex and crown rot of strawberry caused by soilborne fungi limit sustainable strawberry production in the northeastern United States, especially in perennial systems, including matted row and plasticulture. As pathogen populations build up over time in the rhizosphere and infect the root system, feeder roots are pruned, which diminishes nutrient and water uptake and causes stunted plant growth or death. Alternative management options are needed for many organic and small growers who can't use chemical fumigants due to new regulations and potential health hazards. Strawberry plug plants were grown on beneficial microbe-inoculated or uninoculated planting mix followed by transplanting in fruiting field plots that either was biofumigated with mustard cover crop (MCC), anaerobically disinfested (ASD), or left untreated. Different combinations of plug plants and field plot treatments were used to determine the efficacy of individual treatments or synergistic effects from combination treatment. Plug plants were transplanted in pretreated plastic mulched raised beds and grown following a typical organically recommended production system. Plants grown on TerraGrow (TG)-inoculated planting mix showed enhanced plant vigor in the fruiting field compared with untreated plants. Weeds that grew through planting holes were significantly (P ≤ 0.045) suppressed in ASD plots compared with untreated plots in the first year. Plants treated with a combination treatment of TG and ASD had significantly higher fruit yield in both years (2019 and 2020), although the difference was greater in the second year. Plant vigor and survival in treated plots except MCC were also significantly higher in the second year compared with the untreated control. Suppression of pathogenic microbes and plant vigor improvement in treated plots appear to be the factors providing beneficial effects and higher net economic return. Taken together, our results suggest that a combination of beneficial microbes and ASD could be an alternative to synthetic fumigation in a perennial strawberry production system.


Assuntos
Fragaria , Probióticos , Solo , Mostardeira , Fragaria/microbiologia , Bactérias Anaeróbias , Bactérias
2.
Environ Monit Assess ; 195(1): 201, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36525097

RESUMO

Despite being a historically significant and biologically diverse protected area in Bangladesh, Bhawal National Park (BNP) has been the victim of anthropogenic activities that have challenged its sustainability. This study aims to determine the extent of landscape change and forest area depletion within BNP territory from 2005 to 2020, as land use change is the most visible indicator of human footprint liable to biodiversity loss and land degradation. Landsat satellite images from four sensors are used in this research (MSS, TM, OLI, and TIRS). The complex spatial composition of Bhawal National Park was characterized using a supervised classification technique using ArcMap version 10.8. The findings show a steady decline in the dense and degraded forest classifications, but an increase in the other classed classes. Waterbody, settlement, and chala/baid are found to increase by approximately 105, 369, and 650% respectively from 2005 till 2020, while, the area of dense and degraded forest decreased by about 47 and 51%. Within 16 years, nearly 1000 ha of dense forest cover has been depleted. Comparing the latest classified image of BNP with the relevant map, Bhabanipur, B.K. Bari, and Boupara beat are identified to be the most degraded areas. The conclusion can be drawn from this study that owing to most suppressing factors, namely settlement and chala/baid, a forest cover of nearly 2284 ha has been depleted from this national park which is almost 49% of the total possessed forest cover in 2005.


Assuntos
Conservação dos Recursos Naturais , Parques Recreativos , Humanos , Conservação dos Recursos Naturais/métodos , Bangladesh , Monitoramento Ambiental/métodos , Florestas
3.
Materials (Basel) ; 15(6)2022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35329762

RESUMO

This study presents an experimental investigation on the low-velocity impact response of three-dimensional integrated woven spacer sandwich composites made of high-performance glass fiber reinforced fabric and epoxy resin. 3D integrated woven spacer sandwich composites with five different specifications were produced using a hand lay-up process and tested under low-velocity impact with energies of 5 J, 10 J, and 15 J. The results revealed that the core pile's heights and diverse impact energies significantly affect the stiffness and energy absorption capacity. There is no significant influence of face sheet thickness on impact response. Moreover, the damage morphologies of 3D integrated woven spacer sandwich composites under different impact energies were analyzed by simple visualization of the specimen. Different damage and failure mechanisms were observed, including barely visible damage, visible damage, and clearly visible damage. Moreover, it was noticed that the damage of 3D integrated woven spacer sandwich composites samples only constraints to the impacted area and does not affect the integrity of the samples.

4.
Materials (Basel) ; 14(15)2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34361484

RESUMO

Three-dimensional integrated woven spacer sandwich composites have been widely used as industrial textiles for many applications due to their superior physical and mechanical properties. In this research, 3D integrated woven spacer sandwich composites of five different specifications were produced, and the mechanical properties and performance were investigated under different load conditions. XR-CT (X-ray computed tomography) images were employed to visualize the microstructural details and analyze the fracture morphologies of fractured specimens under different load conditions. In addition, the effects of warp and weft direction, face sheet thickness, and core pile height on the mechanical properties and performance of the composite materials were analyzed. This investigation can provide significant guidance to help determine the structure of composite materials and design new products according to the required mechanical properties.

5.
Materials (Basel) ; 14(16)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34443194

RESUMO

The curing kinetics can influence the final macroscopic properties, particularly the three-point bending of the fiber-reinforced composite materials. In this research, the curing kinetics of commercially available glass fiber/epoxy resin prepregs were studied by non-isothermal differential scanning calorimetry (DSC). The curing kinetic parameters were obtained by fitting and the apparent activation energy Ea of the prepreg, the pre-exponent factor, and the reaction order value obtained. A phenomenological nth-order curing reaction kinetic model was established according to Kissinger equation and Crane equation. Furthermore, the optimal curing temperature of the prepregs was obtained by the T-ß extrapolation method. A vacuum hot pressing technique was applied to prepare composite laminates. The pre-curing, curing, and post-curing temperatures were 116, 130, and 153 °C respectively. In addition, three-point bending was used to test the specimens' fracture behavior, and the surface morphology was analyzed. The results show that the differences in the mechanical properties of the samples are relatively small, indicating that the process settings are reasonable.

6.
Z Naturforsch C J Biosci ; 73(5-6): 247-256, 2018 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-29652669

RESUMO

Plant growth-promoting bacteria that are also capable of suppressing plant pathogenic fungi play an important role in sustainable agriculture. There is a critical need for conducting research to discover, characterize and evaluate the efficacy of new strains of such bacteria in controlling highly aggressive plant pathogens. In this study, we isolated endophytic bacteria from medicinal plants of Bangladesh and evaluated their antagonistic capacity against an important phytopathogenic fungus Sclerotinia sclerotiorum. Growth-promoting effects of those isolates on cucumber and rice seedlings were also assessed. Among 16 morphologically distinct isolates, BDR-2, BRtL-2 and BCL-1 significantly inhibited the growth of S. sclerotiorum through induction of characteristic morphological alterations in hyphae and reduction of mycelial dry weight. When cucumber and rice seeds were treated with these endophytic bacteria, seven isolates (BCL-1, BDL-1, BRtL-2, BRtL-3, BDR-1, BDR-2 and BBoS-1) enhanced seed germination, seedling vigor, seedling growth and number of roots per plant at a varying level compared to untreated controls. All isolates produced high levels of indole-3-acetic acid (6 to 63 µg/mL) in vitro. Two most potential isolates, BDR-2 and BRtL-2, were identified as Bacillus amyloliquefaciens and B. subtilis, respectively, based on the 16S rRNA gene sequencing. These results suggest that endophytic Bacillus species from native medicinal plants have great potential for being used as natural plant growth promoter and biopesticides in sustainable crop production.


Assuntos
Ascomicetos/efeitos dos fármacos , Bacillus/fisiologia , Plantas Medicinais/microbiologia , Sementes/crescimento & desenvolvimento , Bacillus/classificação , Bangladesh , Cucumis sativus/crescimento & desenvolvimento , Cucumis sativus/microbiologia , Endófitos/classificação , Endófitos/fisiologia , Oryza/crescimento & desenvolvimento , Oryza/microbiologia , Filogenia , Doenças das Plantas/microbiologia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , RNA Ribossômico 16S/genética , Sementes/microbiologia , Análise de Sequência de RNA
7.
Nephrol Dial Transplant ; 27(8): 3176-81, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22399491

RESUMO

BACKGROUND: The effect of intrarenal renin-angiotensin system (RAS) activity on risk of chronic kidney disease (CKD) has not been well studied in human subjects. METHODS: We investigated the association between urinary angiotensinogen, a reliable biomarker of intrarenal RAS activity, and risk of CKD in 201 patients and 201 controls. CKD was defined as estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m(2) or presence of albuminuria ( ≥ 30 mg/24 h). RESULTS: Compared to controls, median urinary angiotensinogen excretion (45.4 versus 7.4 µg/24 h, P < 0.0001) and angiotensinogen-to-creatinine ratio (26.3 versus 4.4 µg/g, P < 0.0001) were significantly higher in patients with CKD. Log-transformed urinary angiotensinogen excretion and angiotensinogen-to-creatinine ratio were inversely correlated with eGFR (r = -0.59 and -0.57, both P < 0.0001) and positively correlated with log-transformed urinary albumin excretion (r = 0.89 and 0.87, both P < 0.0001). After adjusting for multiple covariables, including the use of angiotensin-converting enzyme inhibitors and/or angiotensin II receptor blockers, diuretics and statins, the odds ratios (95% confidence interval) for CKD comparing the highest tertile to the lowest two tertiles of urinary angiotensinogen excretion and angiotensinogen-to-creatinine ratio were 6.70 (3.43, 13.1; P < 0.0001) and 6.45 (3.34, 12.4; P < 0.0001), respectively. CONCLUSIONS: These data indicate the intrarenal RAS may play an important role in the etiology of CKD, and urinary angiotensinogen may be a useful clinical biomarker for the identification of patients at a high risk for CKD.


Assuntos
Angiotensinogênio/urina , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/urina , Adulto , Idoso , Albuminúria/etiologia , Albuminúria/urina , Angiotensinogênio/sangue , Biomarcadores/urina , Estudos de Casos e Controles , Creatinina/urina , Feminino , Taxa de Filtração Glomerular , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência Renal Crônica/fisiopatologia , Sistema Renina-Angiotensina/fisiologia , Fatores de Risco
8.
Am J Perinatol ; 28(6): 425-30, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21089008

RESUMO

Accurate estimation of the glomerular filtration rate (GFR) in patients with preeclampsia requires the collection of a 24-hour urine and can have important therapeutic and diagnostic implications. This procedure is often difficult or impossible to accomplish in this patient group. In this study, the Cockcroft-Gault, the Modification of Diet in Renal Disease (MDRD), and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formulas were evaluated for their accuracy in determining GFR in the setting of preeclampsia. The estimated GFRs calculated from the above formulas were compared with the creatinine clearance values obtained from a 24-hour urine collections in 543 preeclamptic patients recruited from several large hospitals. Additionally, a set of new equations, preeclampsia GFR (PGFR), based on ethnicity, was created. The Cockcroft-Gault, MDRD, and CKD-EPI formulas were inaccurate in predicting GFR and both were significantly less accurate than PGFR. The latter formula provided an estimated GFR that was much closer to the creatinine clearance. Current GFR estimation equations based on serum creatinine values in nonpregnant patients are not reliable measures of renal function in patients with preeclampsia. The use of a new formula (PGFR) is recommended.


Assuntos
Algoritmos , Taxa de Filtração Glomerular , Pré-Eclâmpsia/fisiopatologia , Adulto , Negro ou Afro-Americano , Povo Asiático , Creatinina/urina , Feminino , Humanos , Modelos Lineares , Pré-Eclâmpsia/etnologia , Pré-Eclâmpsia/urina , Gravidez , Reprodutibilidade dos Testes , População Branca , Adulto Jovem
9.
Int J Environ Health Res ; 19(1): 17-29, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19241244

RESUMO

We introduced flocculant-disinfectant water treatment for 12 weeks in 103 households in Bangladesh to assess if drinking water would be chemically and microbiologically improved and the body burden of arsenic reduced. The median concentration of arsenic in tubewell water decreased by 88% after introduction of the flocculant-disinfectant from 136 microg/l at baseline to 16 (p < 0.001). The median concentration of total urinary arsenic decreased 42% from 385 microg/g creatinine at baseline to 225 microg/g creatinine after intervention (p < 0.001). Among 206 post-intervention drinking water samples that were reportedly treated on the date the sample was collected, 99 (48%) lacked residual free chlorine and 100 (49%) were contaminated with thermotolerant coliforms. The flocculant-disinfectant markedly reduced arsenic in drinking water, but treated drinking water was frequently contaminated with fecal organisms. The lesser reduction in urinary arsenic compared to water arsenic and the health consequences of this reduction require further research.


Assuntos
Intoxicação por Arsênico/prevenção & controle , Desinfetantes , Purificação da Água/métodos , Abastecimento de Água/normas , Adolescente , Adulto , Idoso , Arsênio/química , Arsênio/urina , Intoxicação por Arsênico/epidemiologia , Bangladesh/epidemiologia , Cloro/química , Exposição Ambiental/prevenção & controle , Fezes/microbiologia , Feminino , Floculação , Humanos , Pessoa de Meia-Idade , Saúde da População Rural , Microbiologia da Água , Poluentes Químicos da Água/química , Poluentes Químicos da Água/urina , Abastecimento de Água/análise , Adulto Jovem
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