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The relationship between the excess volume and the structure of Fe-Cr-Ni melts is investigated using containerless levitation and in situ high-energy synchrotron x-ray diffraction techniques. The density of six hypoeutectic Fe-Cr-Ni alloys along the 72 wt. % Fe isopleth was measured in the stable and undercooled regions, and the excess volume was evaluated as a function of Cr concentration. It is found that the 72Fe-Cr-Ni alloys exhibit a positive sign of excess volume and the amount increases with increasing Cr concentration. Analysis of the structure factor and pair distribution function of the alloy family reveals that the short-range order in the melt becomes more pronounced with decreasing Cr concentration; this demonstrates a direct correlation between the excess volume and local liquid structure. A characteristic signature of the icosahedral structure is observed in the structure factor of the melts, and the potential origin of the positive excess volume of the 72Fe-Cr-Ni alloys is qualitatively discussed in relation to the icosahedral structure.
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Phytophthora capsici is an important plant pathogen capable of infecting several major vegetable crops. Water-induced P. capsici transport is considered to be a significant contributor to disease outbreaks and subsequent crop loss. However, little is known about factors controlling P. capsici zoospore transport in porous media, thus impeding our understanding of their environmental dispersal and development of filtration techniques for contaminated irrigation water. This study investigated the transport and retention of P. capsici zoospores in saturated columns packed with iron-oxide-coated sand (IOCS) or uncoated sand in Na(+) or Ca(2+) background solution at pH 7.7 ± 0.5 or 4.0 ± 0.3, in combination with XDLVO interaction energy calculations and microscopic visualizations. Significantly more encysted zoospores were retained in IOCS than in uncoated sand, and at pH 4.0 than at pH 7.7, which likely resulted from increased electrostatic attraction between zoospores and grain surface. At pH 7.7, up to 99% and 96% of the encysted zoospores were removed in IOCS and uncoated sand, respectively, due to a combination of strong surface attachment, pore straining, and adhesive interactions. Motile biflagellate zoospores were more readily transported than encysted zoospores, thus posing a greater dispersal and infection risk. This study has broad implications in environmental transport of Phytophthora zoospores in natural soils as well as in cost-effective engineered filtration systems.
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Phytophthora , Dióxido de Silicio/farmacología , Filtración , Porosidad , AguaRESUMEN
This study was conducted to determine the soil organic carbon (SOC) stock change factor for green manure crops that was developed by the Intergovernmental Panel on Climate Change (IPCC) Tier 2 method and compare this with the net global warming potential (GWP) index that is used to evaluate the contribution of green manuring to global warming. Four treatments were barley (Hordeum vulgare L.; B), hairy vetch (Vicia villosa R.; HV), a barley/hairy vetch mixture (BHV) and a conventional treatment (C). The aboveground biomass of green manure crops was incorporated into the soil on 25 May 2018, 26 April 2019, 29 April 2020, 30 April 2021 and 2 May 2022. Maize (Zea mays L.) was transplanted as the subsequent crop after the incorporation of green manures. SOC stock decreased with green manures, even though carbon input with green manures, including B, HV and BHV, was greater than that with C. The mean value of the SOC stock change factor for green manure crops, including B, HV and BHV was 0.627 and was significantly lower than that of the C. However, the net GWP also decreased with the incorporation of green manure crops, and the mean value of the relative net GWP index across B, HV and BHV was 0.853. These conflicting results were caused by different estimation methods between annual SOC change (â³SOC) and net GWP. The estimation of SOC stock change using â³SOC suggested by the IPCC method may overestimate the contribution of green manure crops to global warming. The net GWP method with comprehensive input and output of carbon in the soil system could provide a better understanding of the carbon balance in soil systems. In the current study, the comparison of â³SOC and net GWP was conducted for at one site of upland soil for 5 years. Therefore, further research on estimating the effect of green manure crops on net GWP in various types of soil for longer years should be conducted.
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Hordeum , Suelo , Calentamiento Global , Carbono , Estiércol , Productos Agrícolas , Zea mays , Agricultura/métodos , Fertilizantes/análisisRESUMEN
Spontaneously occurring spinal epidural hematomas are uncommon clinical findings, and the chronic form is the rarest and its most frequent location is the lumbar spine. Pure radicular involvement is far less frequent than myelopathy. We report a case of progressive radiculopathy in a 52-year-old man with spontaneously occurring cervical epidural hematoma (SCEH). The patient had left hand weakness and numbness for 4 months. MRI scan showed small space-occupying lesion around left 8th cervical nerve root. After surgery we confirmed chronic organizing epidural hematoma. To the best of our knowledge, this is the second reported case in the worldwide literature of pure radiculopathy in a patient with chronic SCEH.
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Vértebras Cervicales/patología , Hematoma Espinal Epidural/complicaciones , Radiculopatía/etiología , Raíces Nerviosas Espinales/patología , Vértebras Cervicales/cirugía , Hematoma Espinal Epidural/patología , Hematoma Espinal Epidural/cirugía , Humanos , Masculino , Persona de Mediana Edad , Radiculopatía/patología , Radiculopatía/cirugía , Raíces Nerviosas Espinales/cirugía , Resultado del TratamientoRESUMEN
Skin graft surgery is a standard treatment that increases the survival rate of patients with burn injuries; however, it leaves many sequelae. Conventional external preparations for the treatment of burns also have various side effects. In this retrospective case study, we assessed the cases of four patients with topical third-degree burns who did not wish to undergo the skin graft surgeries recommended by medical doctors and were thus treated using traditional medicine alone. A Korean medicine doctor administered integrative traditional medicine treatment to the patients using acupuncture and herbal ointments. Analysis of the patients' treatment photographs, quantitative evaluation indices, and vivid narratives suggested that their skin recovered well without adverse effects. Traditional Korean medicine treatment, including acupuncture and herbal ointment treatment, can be a new alternative therapeutic strategy for the treatment of patients with topical burns who do not want to undergo skin graft surgery or who have higher risks for poor surgical outcomes.
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Terapia por Acupuntura , Quemaduras , Quemaduras/tratamiento farmacológico , Quemaduras/cirugía , Humanos , Pomadas/uso terapéutico , Estudios Retrospectivos , Trasplante de PielRESUMEN
The antioxidant glutathione (GSH) mitigates adverse physio-metabolic effects and defends against abiotic types of stress, such as cadmium (Cd) stress. However, its function and role in resisting Cd phytotoxicity by leveraging plant antioxidant-scavenging, redox-regulating, and hormone-balancing systems have not been comprehensively and systematically demonstrated in the Cd-hyperaccumulating plant Brassica napus L. cv. Tammi (oilseed rape). In this study, the effects of exogenously applied GSH to the leaves of B. napus seedlings exposed to Cd (10 µM) were investigated. As a result, Cd stress alone significantly inhibited growth and increased the levels of reactive oxygen species (ROS) and the bioaccumulation of Cd in the seedlings compared with those in unstressed controls. Furthermore, Cd stress induced an imbalance in plant stress hormone levels and decreases in endogenous GSH levels and GSH redox ratios, which were correlated with reductions in ascorbate (AsA) and/or nicotinamide adenine dinucleotide phosphate (NADPH) redox states. However, the exogenous application of GSH to Cd-stressed B. napus seedlings reduced Cd-induced ROS levels and enhanced antioxidant-scavenging defenses and redox regulation by both increasing seedling AsA, GSH, and NADPH concentrations and rebalancing stress hormones, thereby enhancing Cd uptake and accumulation. These results demonstrate that GSH improved plant redox status by upregulating the AsA-GSH-NADPH cycle and reestablishing normal hormonal balance. This indicates that exogenously applied GSH can mitigate Cd phytotoxicity in B. napus and possibly other plants. Therefore, GSH can potentially be applied to Cd-polluted soil for plant remediation.
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A two-substrate method is developed to simultaneously determine emissivity, transmittance, and reflectance of semitransparent materials with a single measurement under the same environment at elevated temperature. The three quantities can be obtained through the emissivities of substrates and the apparent emissivities resulting from the radiance of the sample heated by substrates. The two-substrate method is compared with the conventional method by measuring sapphire samples with various thicknesses, resulting in good agreements for all the samples. The present method will be useful to measure the temperature dependence of optical properties of porous ceramic materials.
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Thermophysical properties of Fe-Cr-Ni melts are studied using electrostatic levitation and rapid solidification techniques. Six hypoeutectic Fe0.72Cr w Ni(0.28-w) alloys with a Cr/Ni ratio of around 0.8 were melted and solidified at different degrees of undercooling. From the observed relationship between the undercooling and thermal plateau time, the hypercooling limit and heat of fusion of Fe0.72Cr w Ni(0.28-w) melts are determined as a function of Cr mass fraction. A ratio of specific heat and total hemispherical emissivity of the Fe-Cr-Ni melts is calculated using the time-temperature profiles. A new method is presented to evaluate the temperature dependence of specific heat for undercooled melts and applied to this alloy family.
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New classes of emerging contaminants such as pharmaceuticals, antibiotic resistant bacteria (ARB), and antibiotic resistance genes (ARGs) have received increasing attention due to rapid increases of their abundance in agroecosystems. As food consumption is a direct exposure pathway of pharmaceuticals, ARB, and ARGs to humans, it is important to understand changes of bacterial communities and ARG profiles in food crops produced with contaminated soils and waters. This study examined the level and type of ARGs and bacterial community composition in soil, and lettuce shoots and roots under soil-surface or overhead irrigation with pharmaceuticals-contaminated water, using high throughput qPCR and 16S rRNA amplicon sequencing techniques, respectively. In total 52 ARG subtypes were detected in the soil, lettuce shoot and root samples, with mobile genetic elements (MGEs), and macrolide-lincosamide-streptogramin B (MLSB) and multidrug resistance (MDR) genes as dominant types. The overall abundance and diversity of ARGs and bacteria associated with lettuce shoots under soil-surface irrigation were lower than those under overhead irrigation, indicating soil-surface irrigation may have lower risks of producing food crops with high abundance of ARGs. ARG profiles and bacterial communities were sensitive to pharmaceutical exposure, but no consistent patterns of changes were observed. MGE intl1 was consistently more abundant with pharmaceutical exposure than in the absence of pharmaceuticals. Pharmaceutical exposure enriched Proteobacteria (specifically Methylophilaceae) and decreased bacterial alpha diversity. Finally, there were significant interplays among bacteria community, antibiotic concentrations, and ARG abundance possibly involving hotspots including Sphingomonadaceae, Pirellulaceae, and Chitinophagaceae, MGEs (intl1 and tnpA_1) and MDR genes (mexF and oprJ).
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Farmacorresistencia Microbiana/genética , Genes Bacterianos , Lactuca/microbiología , Microbiología del Suelo , Contaminantes del Suelo/análisis , Contaminantes del Agua/análisis , Bacterias/efectos de los fármacos , Lactuca/química , ARN Bacteriano/análisis , ARN Ribosómico 16S/análisisRESUMEN
Understanding the uptake and accumulation of pharmaceuticals in vegetables under typical irrigation practices is critical to risk assessment of crop irrigation with reclaimed water. This study investigated the pharmaceutical residues in greenhouse lettuce under overhead and soil-surface irrigations using pharmaceutical-contaminated water. Compared to soil-surface irrigation, overhead irrigation substantially increased the pharmaceutical residues in lettuce shoots. The increased residue levels persisted even after washing for trimethoprim, monensin sodium, and tylosin, indicating their strong sorption to the shoots. The postwashing concentrations in fresh shoots varied from 0.05 ± 0.04 µg/kg for sulfadiazine to 345 ± 139 µg/kg for carbamazepine. Root concentration factors ranged from 0.04 ± 0.14 for tylosin to 19.2 ± 15.7 for sulfamethoxazole. Translocation factors in surface-irrigated lettuce were low for sulfamethoxalzole, trimethoprim, monensin sodium, and tylosin (0.07-0.15), but high for caffeine (4.28 ± 3.01) and carbamazepine (8.15 ± 2.87). Carbamazepine was persistent in soil and hyperaccumulated in shoots.
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Riego Agrícola/métodos , Residuos de Medicamentos/análisis , Lactuca/metabolismo , Preparaciones Farmacéuticas/metabolismo , Contaminantes Químicos del Agua/metabolismo , Carbamazepina/análisis , Contaminación de Alimentos , Lactuca/química , Monensina/análisis , Preparaciones Farmacéuticas/análisis , Hojas de la Planta/química , Raíces de Plantas/química , Suelo/química , Contaminantes del Suelo/análisis , Contaminantes del Suelo/metabolismo , Sulfametoxazol/análisis , Trimetoprim/análisis , Tilosina/análisis , Verduras , Contaminantes Químicos del Agua/análisisRESUMEN
STUDY DESIGN: This is a retrospective study that was done according to clinical and radiological evaluation. PURPOSE: We analyzed the clinical and radiological outcomes of minimally invasive transforaminal lumbar interbody single level fusion. OVERVIEW OF LITERATURE: Minimally invasive transforaminal lumbar interbody fusion is effective surgical method for treating degenerative lumbar disease. METHODS: The study was conducted on 56 patients who were available for longer than 2 years (range, 24 to 45 months) follow-up after undergoing minimally invasive transforminal lumbar interbody single level fusion. Clinical evaluation was performed by the analysis of the visual analogue scale (VAS) score and the Oswestry Disability Index (ODI) and the Kirkaldy-Willis score. For the radiological evaluation, the disc space height, the segmental lumbar lordotic angle and the whole lumbar lordotic angle were analyzed. At the final follow-up after operation, the fusion rate was analyzed according to Bridwell's anterior fusion grade. RESULTS: For the evaluation of clinical outcomes, the VAS score was reduced from an average of 6.7 prior to surgery to an average of 1.8 at the final follow-up. The ODI was decreased from an average of 36.5 prior to surgery to an average of 12.8 at the final follow-up. In regard to the clinical outcomes evaluated by the Kirkaldy-Willis score, better than good results were obtained in 52 cases (92.9%). For the radiological evaluation, the disc space height (p = 0.002), and the whole lumbar lordotic angle (p = 0.001) were increased at the final follow-up. At the final follow-up, regarding the interbody fusion, radiological union was obtained in 54 cases (95.4%). CONCLUSIONS: We think that if surgeons become familiar with the surgical techniques, this is a useful method for minimally invasive spinal surgery.