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1.
Artigo em Inglês | MEDLINE | ID: mdl-33411284

RESUMO

Cadmium pollution in the environment is ubiquitous and can be a serious health issue. Crop straw-based biochar is a promising adsorbent, yet few studies have systematically examined the effects of both feedstock and pyrolysis temperature on biochar efficacy for cadmium (Cd) sorption. Sorption-desorption experiments were conducted to explore the mechanisms of Cd sorption for biochars derived from wheat straw (WSB), rape straw (RASB), soybean straw (SSB), and peanut straw (PSB) feedstocks, which were produced by pyrolysis at 450 °C and 650 °C. For biochars pyrolyzed at 450 °C, the sorption capacities varied as PSB>SSB>RASB≈WSB, while the order changed as RASB≈WSB>PSB>SSB for 650 °C biochars. With the increase in pyrolysis temperature, for wheat straw biochar and rape straw biochars, Cd sorption capacities increased by 72% and 63%, while there were 61% and 63% decreases for peanut straw biochar and soybean straw biochar, respectively. Compared to the non-legume straw biochars (WSB and RASB), legume straw biochars (SSB and PSB) have higher sorption capacities for Cd. Peanut straw biochar (PSB) produced at 450 °C was found to be the most promising adsorbent for cadmium. Examination of the sorbed biochars using a range of analytical techniques indicated that 450 °C PSB immobilized cadmium by precipitation with non-electrostatic adsorption. The precipitation of Cd on 450 °C PSB was mainly induced by cation exchange between Cd with mineral cations, which caused Cd complexation with carboxyl functional groups.

2.
Sci Rep ; 11(1): 159, 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33420245

RESUMO

Application of iron (Fe)- and silica (Si)-enhanced biochar compound fertilisers (BCF) stimulates rice yield by increasing plant uptake of mineral nutrients. With alterations of the nutrient status in roots, element homeostasis (e.g., Fe) in the biochar-treated rice root was related to the formation of biominerals on the plaque layer and in the cortex of roots. However, the in situ characteristics of formed biominerals at the micron and sub-micron scale remain unknown. In this study, rice seedlings (Oryza sativa L.) were grown in paddy soil treated with BCF and conventional fertilizer, respectively, for 30 days. The biochar-induced changes in nutrient accumulation in roots, and the elemental composition, distribution and speciation of the biomineral composites formed in the biochar-treated roots at the micron and sub-micron scale, were investigated by a range of techniques. Results of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) showed that biochar treatment significantly increased concentrations of nutrients (e.g., Fe, Si, and P) inside the root. Raman mapping and vibrating sample magnetometry identified biochar particles and magnetic Fe nanoparticles associated with the roots. With Fe plaque formation, higher concentrations of FeOx- and FeOxH- anions on the root surface than the interior were detected by time-of-flight secondary ionization mass spectrometry (ToF-SIMS). Analysis of data from scanning electron microscopy energy-dispersive spectroscopy (SEM-EDS), and from scanning transmission electron microscopy (STEM) coupled with EDS or energy electron loss spectroscopy (EELS), determined that Fe(III) oxide nanoparticles were accumulated in the crystalline fraction of the plaque and were co-localized with Si and P on the root surface. Iron-rich nanoparticles (Fe-Si nanocomposites with mixed oxidation states of Fe and ferritin) in the root cortex were identified by using aberration-corrected STEM and in situ EELS analysis, confirming the biomineralization and storage of Fe in the rice root. The findings from this study highlight that the deposition of Fe-rich nanocomposites occurs with contrasting chemical speciation in the Fe plaque and cortex of the rice root. This provides an improved understanding of the element homeostasis in rice with biochar-mineral fertilization.

3.
Ann Fam Med ; 19(1): 87-88, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33431403
4.
Sci Rep ; 10(1): 16119, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32999343

RESUMO

Obesity is common comorbidity in patients with schizophrenia. Previous studies have reported that homocysteine (Hcy) is increased in schizophrenia. However, no study has reported the association between BMI and Hcy levels in schizophrenia. This cross-sectional naturalistic study aimed to evaluate the relationship between BMI, Hcy and clinical symptoms in Chinese Han patients with chronic schizophrenia. Clinical and anthropometric data as well as plasma Hcy level and glycolipid parameters were collected. Psychopathology was measured with the Positive and Negative Syndrome Scale (PANSS). Our results showed that compared with the low BMI group, the high BMI group had a higher PANSS general psychopathology subscore, higher levels of blood glucose, total cholesterol and high-density lipoprotein (HDL) cholesterol (all p < 0.05). Hcy levels were negatively associated with BMI in patients (p < 0.001). Hcy level, the PANSS general psychopathology subscale, total cholesterol and education (all p < 0.05) were the influencing factors of high BMI. Our study suggest that Hcy level may be associated with BMI in patients with schizophrenia. Moreover, patients with high BMI show more severe clinical symptoms and higher glucose and lipid levels.

5.
Biotechnol Lett ; 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33051809

RESUMO

OBJECTIVE: Lipases are often used in immobilized form, but commercial immobilized lipases are costly. An alternative is to produce lipases in solid-state fermentation, dry the solids and then use the "dry fermented solids" (DFS) directly. We produced DFS by growing Burkholderia contaminans on a mixture of sugarcane bagasse and sunflower seed meal and used the DFS to esterify oleic acid with ethanol in subcritical and supercritical CO2 at 40 °C. RESULTS: Compared to a control without CO2 at atmospheric pressure, subcritical CO2 at 30 bar improved esterification activity 1.2-fold. Higher pressures, including supercritical pressures up to 150 bar, reduced activity to less than 80% of the control. At 30 bar, the esterification activity was improved a further 1.8-fold with the addition of 9% water (i.e. 9 g water per 100 g oleic acid) to the reaction medium. CONCLUSION: A subcritical CO2 atmosphere, with the addition of a small amount of water, improved the esterification activity of DFS containing lipases of Burkholderia contaminans.

7.
Sci Rep ; 10(1): 13816, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-32796884

RESUMO

Biochar may serve as a tool to sustainably mitigate climate change via carbon sequestration and by improving soil fertility. Biochar has shown to retain nitrate in its pores, which increases with an organic coating of the inner surfaces and residence time in soil ("aging"). Here we investigated the plant accessibility of the captured nitrate in field-aged biochar, as a pre-requisite for developing carbon-based N fertilization techniques with environmental benefits. Based on previous results, we hypothesized that part of the biochar-captured nitrate would remain unavailable for plants. A two-factorial greenhouse experiment was designed, where the N was applied either as Ca(NO3)2 or as N captured in field-aged biochar at five increasing N doses to quinoa and perennial ryegrass in pots. Interestingly, the biochar-captured N was as plant available as the mineral nitrate, except for the highest dosage. Refuting our hypothesis, no significant amounts of N were extractable at the end of the study from the biochar-soil mixtures with repeated-extraction protocols. Thus, N captured by biochar may improve the N use efficiency in agriculture. Further research should evaluate the role of biochar particle size, root morphology, mycorrhization, and soil moisture (variations) for nitrate retrieval from biochar particles by plants because the captured biochar N was less available in the field as under present controlled conditions.

8.
Small ; : e2001978, 2020 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-32548963

RESUMO

The discovery of Pickering emulsion templated assembly enables the design of a hybrid colloidal capsule with engineered properties. However, the underlying mechanisms by which nanoparticles affect the mechanical properties of the shell are poorly understood. Herein, in situ mechanical compression on the transmission electron microscope and aberration-corrected scanning transmission microscope are unprecedentedly implemented to study the intrinsic effect of nanoparticles on the mechanical properties of the calcium carbonate (CaCO3 )-decorated silica (SiO2 ) colloidal capsule. The stiff and brittle nature of the colloidal capsule is due to the interfacial chemical bonding between the CaCO3 nanoparticles and SiO2 inner shell. Such bonding strengthens the mechanical strength of the SiO2 shell (166 ± 14 nm) from the colloidal capsule compared to the thicker single SiO2 shell (310 ± 70 nm) from the silica hollow sphere. At elevated temperature, this interfacial bonding accelerates the formation of the single calcium silicate shell, causing shell morphology transformation and yielding significantly enhanced mechanical strength by 30.9% and ductility by 94.7%. The superior thermal durability of the heat-treated colloidal capsule holds great potential for the fabrication of the functional additives that can be applied in the wide range of applications at elevated temperatures.

10.
Nanoscale ; 12(24): 12760-12766, 2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32537621

RESUMO

The concept of composite material has been increasingly applied for the significant improvement in the thermoelectric performance because of the predictable effective medium properties and the unique interfacial correlated thermal and electrical transport mechanism. Herein, we report that the graphene inclusion can lead to a significant reduction in thermal conductivity and improve the overall thermoelectric figure-of-merit in SnSe. We demonstrate a systematic investigation on the microstructures and electrical and thermoelectric properties of the SnSe/graphene composite. HRTEM reveals the uniform distribution of graphene nanosheets in the SnSe matrix, forming a sharp interface with refined SnSe grain sizes and defects nearby the interfaces. Thermal conductivity decreases with graphene addition and can significantly reduce to as low as ∼0.18 W m-1 K-1, resulting in an enhanced figure of merit (ZT) of the SnSe/graphene composite by at least 50% compared with pristine SnSe. The significant reduction in thermal conductivity is attributed to the phonon scattering by densely distributed phase interfaces as well as defects and grain boundaries. The carbon element is also believed to potentially reduce long-range tin diffusion by acting as a confinement barrier to restrict heat and ion diffusion. Our work proves that the graphene secondary phase could enhance the ZT of the SnSe matrix, which might pave the way for achieving high-performance thermoelectric properties in carbon-induced composite materials.

11.
Arthroplast Today ; 6(2): 169-171, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32368606

RESUMO

Revision hip arthroplasty is a frequently performed procedure and is projected to increase annually. Removal of a well-fixed acetabular component can involve loss of much needed bone stock. Contemporary instruments allow acetabular removal with minimal morbidity; however, their use requires accurate knowledge of the component size. We describe a technique that allows sizing to be determined accurately, without specialized equipment, in situations where component details are unavailable. Our technique multiplies ratio of head:cup on pre-operative X-ray by the diameter of the index femoral head which is removed intra-operatively to predict index cup size. This novel surgical technique appears accurate in prediction of cup size to guide explant in revision hip arthroplasty.

12.
Sci Total Environ ; 724: 138153, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32251884

RESUMO

The use of biochar in avocado orchard soils has not yet been investigated in rigorous scientific experiments. We determine the effect of wood biochar on avocado growth, fruit production and economic benefit. Biochar was applied at 0%, 5%, 10% and 20% volume by volume basis. Biochar significantly improved the growth of avocado seedlings and increased fruit yield in the first three years after planting. There was an overall increase in soil carbon, fruit yield, tree diameter and height in all biochar treatments relative to the control over the seasons. Trees planted with biochar had 18-26% greater growth rates (in terms of height and stem diameter) than the control. Tree diameter was significantly greater with biochar (145.4 ± 3.3 mm) relative to the control treatment (125.0 ± 2.7 mm). Tree height was also significantly greater with biochar (3.7 ± 0.1 m) relative to the control treatment (3.4 ± 0.1 m). The fruit count from the biochar row was significantly greater (97%) in 2018. Heavy bearing trees typically have a lower yield in the subsequent year but despite this, the 2019 fruit counts were higher in aggregate for the biochar amended trees (20%) relative to the control. A cost-benefit analysis indicated that if yield surplus of fruit trees continued for three years, and assuming avocado prices remain at similar levels, then the discounted net benefit over a hectare would amount to US$8581, or US$105 per metric tonne of biochar applied.


Assuntos
Persea , Solo , Carbono , Carvão Vegetal
13.
Sci Total Environ ; 725: 138359, 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32278180

RESUMO

Fusarium head blight (FHB), caused by the fungal pathogen Fusarium graminearum, is a destructive and widespread wheat disease. Chemical fungicides are becoming less effective at reducing the disease severity of FHB, and there is a need to find a more effective, low-cost natural product. A by-product of the pyrolysis of wheat straw is a condensate known as wheat straw vinegar, which was hypothesized to be an effective F. graminearum inhibitor in wheat. The organic and mineral compositions of wheat straw vinegar were analyzed. The results of GC-MS indicated that the major organic compounds in wheat straw vinegar are phenolics and acetic acid. The main inorganic elements in the liquid were K, Ca, S and Mg. A bio-test of wheat straw vinegar showed strong antifungal activity on F. graminearum growth and production of deoxynivalenol (DON) with an EC50 (concentration for 50% of maximal effect) value of 3.1 µl ml-1. Field tests showed that the application of wheat straw vinegar diluted 200-fold significantly decreased the wheat FHB infection rate and DON content by 66% and 69%, respectively. The control efficacy of wheat straw vinegar at a dilution of 200-fold was similar to that of typical chemical fungicide applications. The use of wheat straw vinegar may increase farmers' income by reducing the net fungicide costs. Therefore, wheat straw vinegar has high potential as a natural fungicide for the control of FHB and can reduce the dependence on synthetic fungicides.


Assuntos
Fungicidas Industriais , Fusarium , Ácido Acético , Análise Custo-Benefício , Doenças das Plantas , Triticum
14.
Pediatr Blood Cancer ; 67(7): e28263, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32323913

RESUMO

INTRODUCTION: Indications for hematopoietic stem cell transplantation (HSCT) in pediatric acute myeloid leukemia (AML) are primarily dependent on risk stratification at diagnosis and relapse status. We sought to determine whether access to HSCT is influenced by regional and socioeconomic factors. METHODS: Children with newly diagnosed AML aged < 15 years between 2001 and 2015 were identified using the Cancer in Young People in Canada national population-based registry. Factors potentially associated with the receipt of HSCT were studied using univariate and multivariable logistic regression models. RESULTS: Overall, 568 children with newly diagnosed AML were included and 262 (46%) received HSCT. A greater proportion of patients, 103/157 (65.6%), underwent HSCT after first or subsequent relapse compared to 159/411 (38.7%) patients who underwent transplant before relapse. Among patients for whom HSCT would be considered before relapse, factors associated with higher odds of HSCT in a multivariable analysis were: poor versus good-risk cytogenetics (Odds ratio [OR]: 30.0, 95% confidence interval [CI]: 7.7-117.0), diagnosis during 2012-2015 versus 2001-2006 (OR: 3.2, 95% CI: 1.6-6.3), diagnosis in eastern Canada versus central Canada (OR: 3.7, 95% CI: 1.9-7.3), and age 10-14 years versus age < 1 year (OR: 5.4, 95% CI: 2.3-12.8). Among patients for whom HSCT would be considered after first relapse, higher odds of HSCT was associated with diagnosis at a HSCT center (OR: 2.1, 95% CI: 1.1-4.1). CONCLUSION: Patients diagnosed at a HSCT performing center and patients from eastern Canada had higher odds of receiving HSCT. This may suggest preferential access to HSCT for certain patients.


Assuntos
Doença Enxerto-Hospedeiro/epidemiologia , Acesso aos Serviços de Saúde/estatística & dados numéricos , Transplante de Células-Tronco Hematopoéticas/métodos , Leucemia Mieloide Aguda/terapia , Recidiva Local de Neoplasia/epidemiologia , Adolescente , Canadá/epidemiologia , Criança , Pré-Escolar , Feminino , Seguimentos , Doença Enxerto-Hospedeiro/diagnóstico , Humanos , Incidência , Lactente , Leucemia Mieloide Aguda/patologia , Masculino , Recidiva Local de Neoplasia/diagnóstico , Prognóstico , Estudos Retrospectivos , Condicionamento Pré-Transplante , Transplante Homólogo
15.
J Surg Case Rep ; 2020(3): rjaa033, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32211147

RESUMO

Roux-en-Y gastric bypass (RYGB) is the second most common bariatric procedure performed in Australia, second to sleeve gastrectomy. Banding of pouches and anastomoses, via silastic bands or MiniMizer rings, have been used to assist in improving restriction. Though banded gastric bypasses are effective in weight loss, band migration, whether it be slippage or erosion, occurs in up to 7% of banded bariatric procedures. Jejunal intussusception and internal herniation are both individually known complications of RYGB. It is, however, rare to have all three phenomenon occur in a single patient. In this study, the authors present a report of a middle-aged lady, 2 years post-primary RYGB with MiniMizer gastric ring insertion presenting with all three complications.

16.
FEMS Microbiol Rev ; 44(3): 253-304, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32149348

RESUMO

Echoing the repeated convergent evolution of flight and vision in large eukaryotes, propulsive swimming motility has evolved independently in microbes in each of the three domains of life. Filamentous appendages - archaella in Archaea, flagella in Bacteria and cilia in Eukaryotes - wave, whip or rotate to propel microbes, overcoming diffusion and enabling colonization of new environments. The implementations of the three propulsive nanomachines are distinct, however: archaella and flagella rotate, while cilia beat or wave; flagella and cilia assemble at their tips, while archaella assemble at their base; archaella and cilia use ATP for motility, while flagella use ion-motive force. These underlying differences reflect the tinkering required to evolve a molecular machine, in which pre-existing machines in the appropriate contexts were iteratively co-opted for new functions and whose origins are reflected in their resultant mechanisms. Contemporary homologies suggest that archaella evolved from a non-rotary pilus, flagella from a non-rotary appendage or secretion system, and cilia from a passive sensory structure. Here, we review the structure, assembly, mechanism and homologies of the three distinct solutions as a foundation to better understand how propulsive nanomachines evolved three times independently and to highlight principles of molecular evolution.

17.
Blood ; 135(15): 1287-1298, 2020 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-32047896

RESUMO

Human graft-versus-host disease (GVHD) biology beyond 3 months after hematopoietic stem cell transplantation (HSCT) is complex. The Applied Biomarker in Late Effects of Childhood Cancer study (ABLE/PBMTC1202, NCT02067832) evaluated the immune profiles in chronic GVHD (cGVHD) and late acute GVHD (L-aGVHD). Peripheral blood immune cell and plasma markers were analyzed at day 100 post-HSCT and correlated with GVHD diagnosed according to the National Institutes of Health consensus criteria (NIH-CC) for cGVHD. Of 302 children enrolled, 241 were evaluable as L-aGVHD, cGVHD, active L-aGVHD or cGVHD, and no cGVHD/L-aGVHD. Significant marker differences, adjusted for major clinical factors, were defined as meeting all 3 criteria: receiver-operating characteristic area under the curve ≥0.60, P ≤ .05, and effect ratio ≥1.3 or ≤0.75. Patients with only distinctive features but determined as cGVHD by the adjudication committee (non-NIH-CC) had immune profiles similar to NIH-CC. Both cGVHD and L-aGVHD had decreased transitional B cells and increased cytolytic natural killer (NK) cells. cGVHD had additional abnormalities, with increased activated T cells, naive helper T (Th) and cytotoxic T cells, loss of CD56bright regulatory NK cells, and increased ST2 and soluble CD13. Active L-aGVHD before day 114 had additional abnormalities in naive Th, naive regulatory T (Treg) cell populations, and cytokines, and active cGVHD had an increase in PD-1- and a decrease in PD-1+ memory Treg cells. Unsupervised analysis appeared to show a progression of immune abnormalities from no cGVHD/L-aGVHD to L-aGVHD, with the most complex pattern in cGVHD. Comprehensive immune profiling will allow us to better understand how to minimize L-aGVHD and cGVHD. Further confirmation in adult and pediatric cohorts is needed.


Assuntos
Doença Enxerto-Hospedeiro/imunologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Doença Aguda , Antígenos CD/análise , Antígenos CD/imunologia , Linfócitos B/imunologia , Linfócitos B/patologia , Biomarcadores/sangue , Criança , Doença Crônica , Citocinas/sangue , Citocinas/imunologia , Doença Enxerto-Hospedeiro/sangue , Doença Enxerto-Hospedeiro/patologia , Humanos , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/patologia , Linfócitos T/imunologia , Linfócitos T/patologia
18.
Clin Nucl Med ; 45(5): 368-369, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32108703

RESUMO

Hemangioendotheliomas are a heterogeneous group of vascular neoplasm that may affect the liver, bone, and soft tissues. Among its variants, pseudomyogenic hemangioendothelioma is rarely encountered. Pseudomyogenic hemangioendothelioma is usually characterized by multiple soft tissue lesions, with occasional bone lesions. Fewer than 20 cases with exclusive involvement of bone structures have been reported. We describe a case of pseudomyogenic hemangioendothelioma involving multiple bony structures but without soft tissue involvement in a 7-year-old girl, imaged with F-FDG PET/CT at diagnosis and during treatment with mammalian target of rapamycin inhibitors.


Assuntos
Neoplasias Ósseas/diagnóstico por imagem , Hemangioendotelioma/diagnóstico por imagem , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Criança , Feminino , Fluordesoxiglucose F18 , Humanos , Compostos Radiofarmacêuticos
20.
Artigo em Inglês | MEDLINE | ID: mdl-32101408

RESUMO

Thermoelectric (TE) materials have attracted extensive interest because of their ability to achieve direct heat-to-electricity conversion. They provide an appealing renewable energy source in a variety of applications by harvesting waste heat. The record-breaking figure of merit reported for single crystal SnSe has stimulated related research on its polycrystalline counterpart. Boosting the TE conversion efficiency requires increases in the power factor and decreases in thermal conductivity. It is still a big challenge, however, to optimize these parameters independently because of their complex interrelationships. Herein, we propose an innovative approach to decouple electrical and thermal transport by incorporating carbon fiber (CF) into polycrystalline SnSe. We show that the incorporation of highly conductive CF can successfully enhance the electrical conductivity, while greatly reducing the thermal conductivity of polycrystalline SnSe. As a result, a high TE figure-of-merit (zT) of 1.3 at 823 K is obtained in p-type SnSe/CF composite polycrystalline materials. Furthermore, SnSe samples incorporated with CFs exhibit superior mechanical properties, which are favorable for device fabrication applications. Our results indicate that the dispersion of CF can be a good way to greatly improve both TE and mechanical performance.

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