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1.
J Cancer Res Clin Oncol ; 150(2): 107, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38418608

RESUMEN

BACKGROUND: As the form of World Health Organization Central Nervous System (WHO CNS) tumor classifications is updated, there is a lack of research on outcomes for intracranial combined solitary-fibrous tumor and hemangiopericytoma (SFT/HPC). This study aimed to explore conditional survival (CS) pattern and develop a survival prediction tool for intracranial SFT/HPC patients. METHODS: Data of intracranial SFT/HPC patients was gathered from the Surveillance, Epidemiology, and End Results (SEER) program of the National Cancer Institute. The patients were split into training and validation groups at a 7:3 ratio for our analysis. CS is defined as the likelihood of surviving for a specified period of time (y years), given that the patient has survived x years after initial diagnosis. Then, we used this definition of CS to analyze the intracranial SFT/HPC patients. The least absolute shrinkage and selection operator (LASSO) regression and best subset regression (BSR) were employed to identify predictive factors. The Multivariate Cox regression analysis was applied to establish a novel CS-based nomogram, and a risk stratification system was developed using this model. RESULTS: From the SEER database, 401 patients who were diagnosed with intracranial SFT/HPC between 2000 and 2019 were identified. Among them, 280 were included in the training group and 121 were included in the internal validation group for analysis. Our study revealed that in intracranial SFT/HPC, 5-year survival rates saw significant improvement ranging from 78% at initial diagnosis to rates of 83%, 87%, 90%, and 95% with each successive year after surviving for 1-4 years. The LASSO regression and BSR identified patient age, tumor behavior, surgery and radiotherapy as predictors of CS-based nomogram development. A risk stratification system was also successfully constructed to facilitate the identification of high-risk patients. CONCLUSION: The CS pattern of intracranial SFT/HPC patients was outlined, revealing a notable improvement in 5-year survival rates after an added period of survival. Our newly-established CS-based nomogram and risk stratification system can provide a real-time dynamic survival estimation and facilitate the identification of high-risk patients, allowing clinicians to better guide treatment decision for these patients.


Asunto(s)
Hemangiopericitoma , Tumores Fibrosos Solitarios , Humanos , Hemangiopericitoma/diagnóstico , Hemangiopericitoma/patología , Hemangiopericitoma/cirugía , Tumores Fibrosos Solitarios/diagnóstico , Tumores Fibrosos Solitarios/patología , Tumores Fibrosos Solitarios/cirugía , Análisis de Supervivencia , Pronóstico , Nomogramas
2.
Int Wound J ; 21(4): e14550, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38069518

RESUMEN

Craniotomies are intricate neurosurgical procedures susceptible to post-operative complications, among which surgical site infections (SSIs) are particularly concerning. This study sought to elucidate the potential risk factors and pathogenetic characteristics associated with SSIs following craniotomy procedures in a clinical setting. A retrospective study was conducted from May 2020 to May 2023, examining patients subjected to elective or emergency craniotomies. The cohort underwent post-operative surveillance for SSIs, facilitating patient classification into SSI and Non-SSI groups based on infection occurrence. Data collection encapsulated demographic and clinical parameters, including American Society of Anesthesiologists (ASA) classifications, and operative factors. SSIs were diagnosed via an integrated approach combining clinical symptoms, microbiological culture findings and pertinent laboratory tests. A rigorous statistical methodology employing IBM's SPSS version 27.0 was utilised for data analysis. In a univariate analysis, significant risk factors for post-craniotomy SSIs were identified, with patients aged over 60 displaying a pronounced susceptibility. Moreover, surgeries exceeding a duration of 4 h heightened infection risks. Elevated ASA grades denoted an increased prevalence of SSIs, as did emergency procedures and higher National Nosocomial Infections Surveillance scores. Multivariate analysis pinpointed epidural/subdural drainage as a protective measure against SSIs, whereas emergency surgeries, operative times beyond 4 h and subsequent surgeries within the hospital stay amplified infection risks. Notably, coagulase-negative Staphylococcus dominated the identified pathogens at 28.09%, followed by Escherichia coli (17.98%), Klebsiella pneumoniae (10.11%) and Staphylococcus aureus (11.24%), underscoring the need for diverse prophylactic measures. SSIs following craniotomies present a multifaceted challenge influenced by a confluence of patient-related, operative and post-operative determinants. Understanding these risk factors is paramount in refining surgical protocols and post-operative care strategies to mitigate SSI incidence.


Asunto(s)
Craneotomía , Infección de la Herida Quirúrgica , Humanos , Persona de Mediana Edad , Anciano , Infección de la Herida Quirúrgica/epidemiología , Infección de la Herida Quirúrgica/etiología , Infección de la Herida Quirúrgica/prevención & control , Estudios Retrospectivos , Factores de Riesgo , Craneotomía/efectos adversos , Procedimientos Neuroquirúrgicos/efectos adversos
3.
Environ Res ; 231(Pt 2): 116233, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37236388

RESUMEN

Agricultural activities have recently disturbed the ecosystem of the Qinghai-Tibet Plateau and the shift of antibiotic resistance genes (ARGs) in the different types of farmlands is not well understood, so more comprehensive ecological barrier management measures cannot be provided for the region. This research was performed to exploring ARG pollution in cropland soil on the Qinghai-Tibet Plateau to obtain information on the geographical and climatic factors shaping the ARG distribution. Based on high-throughput quantitative PCR (HT-qPCR) analysis, the ARG abundance in farmland ranged from 5.66 × 105 to 6.22 × 107 copies per gram of soil higher than previous research at soil and wetland in Qinghai-Tibet plateau, and it was higher in wheat and barley soils than in corn soil. The distribution of ARGs exhibited regional features as ARG abundance was adversely affected by mean annual precipitation and temperature with lower temperature and less rainfall at high altitude. According to network analysis and structural equation modeling (SEM), mobile genetic elements (MGEs) and heavy metals are the key drivers of ARG dissemination on the Qinghai-Tibet Plateau as they show negative relationship with ARGs, and selection copressure from heavy metals in cropland soil increases the horizontal gene transfer (HGT) potential of ARGs through synergistic selection effects, each contribution to the ARGs was 19% and 29% respectively. This research suggests the need to focus on controlling heavy metals and MGEs to constrain the dissemination of ARGs, as arable soil is already slightly contaminated by heavy metals.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Tibet , Antibacterianos/farmacología , Ecosistema , Contaminantes del Suelo/análisis , Metales Pesados/análisis , Suelo/química , Farmacorresistencia Microbiana/genética , Genes Bacterianos , Microbiología del Suelo , Productos Agrícolas
4.
World Neurosurg ; 171: e309-e322, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36513299

RESUMEN

OBJECTIVE: To identify the significant prognostic factors of overall survival (OS) for patients living with meningiomas (MMs), and establish a novel graphical nomogram and an online dynamic nomogram. METHODS: Patients diagnosed with MMs were identified retrospectively from the SEER database. The cohort was split into training (70%) and test (30%) groups randomly. Univariable and multivariable Cox models were successively used to screen the significant prognostic factors. Subsequently, the independent predictors were used as items to establish the graphic and dynamic nomogram model. To assess the accuracy of the model, a calibration curve was plotted. To assess the discrimination performance, C-index and time-dependent area under the receiver operator characteristic curve (AUC) were selected. Additionally, the decision curve was generated to evaluate the clinical net benefit of the model. RESULTS: A total of 899 patients were involved, of which 629 and 270 were split into training group and test group, respectively. Age, sex, radiotherapy, tumor size, and tumor histology were identified as the significant prognostic factors. Based on these factors, a graphical nomogram and online nomogram (Web site: https://helloshinyweb.shinyapps.io/dynamic_nomogram/) were developed. The calibration curve showed favorable consistence between predicted and actual survival rate. C-index and time-dependent AUC showed good discrimination ability, and the decision curve analysis showed positive net benefit of the model in clinical practice. CONCLUSIONS: Age of diagnosis, sex, tumor size, tumor histology, and radiotherapy were independent predictors for OS, while extent of resection had a borderline significant. A nomogram model was successfully developed and validated to dynamically predict the long-term OS for MM patients, expecting to help neurosurgeons optimize clinical management and treatment strategies.


Asunto(s)
Neoplasias Meníngeas , Meningioma , Humanos , Estudios Retrospectivos , Nomogramas , Calibración , Programa de VERF
5.
Sci Rep ; 10(1): 15351, 2020 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-32948816

RESUMEN

Agricultural management techniques such as mulching with crop straw can impact soil properties and may in turn change the structure and function of the soil food web. We investigated different straw mulching types and straw mulching coverage levels on soil nematodes community structure in walnut orchards. We set up a randomized experimental design with three straw mulch types, and three straw mulch distance treatments in a walnut plantation. The results indicated that the number of soil nematodes after straw mulching was lower than that found in the control (CK). However, the metabolic and structure footprints of the omnivore-predator nematodes showed higher values as compared to CK. The abundances of plant parasite and omnivore-predator nematodes were negatively correlated with ammonium nitrogen (NH4+-N) and dissolved organic nitrogen (DON), whereas soil moisture content (SM) had a negative correlation with the abundance of total nematodes. High structure index (SI), maturity index (MI) and low enrichment index (EI) values revealed a structured soil food web, medium soil enrichment, and fungal decomposition channel under the mix straw mulching treatments. Soil nematodes should be used as an indicator of soil functional changes resulting from straw mulching.


Asunto(s)
Agricultura/métodos , Juglans , Nematodos , Animales , Biodiversidad , Brassica napus , Carbono/análisis , China , Nitrógeno/análisis , Tallos de la Planta , Suelo/química , Suelo/parasitología
6.
PeerJ ; 8: e9040, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32411523

RESUMEN

Intercropping may improve community stability and yield under climate change. Here, we set up a field experiment to evaluate the advantages of cultivating Z anthoxylum bungeanum with Capsicum annum, and Z. bungeanum with Glycine max as intercrops, compared with cultivating Z. bungeanum in monoculture. Effects of extreme drought stress conditions on morphological, physiological, and biochemical traits of the three crop species cultivated in the three contrasting planting systems were compared. Results showed that extreme drought conditions induced negative impacts on Z. bungeanum grown in monoculture, due to reduced growth and metabolic impairment. However, limited stomatal conductance, reduced transpiration rate (Tr ), and increased water use efficiency, carotenoid content, catalase activity, and accumulation of soluble sugars in Z. bungeanum indicated its adaptive strategies for tolerance of extreme drought stress conditions. Compared with cultivation in monoculture, intercropping with C. annum had positive effects on Z. bungeanum under extreme drought stress conditions, as a result of improved crown diameter, leaf relative water content (LRWC), net photosynthetic rate, and proline content, while intercropping with G. max under extreme drought stress conditions increased net CO2 assimilation rates, LRWC, Tr , and superoxide dismutase (SOD) activity. In conclusion, Z. bungeanum has an effective defense mechanism for extreme drought stress tolerance. Intercropping with G. max enhanced this tolerance potential primarily through its physio-biochemical adjustments, rather than as a result of nitrogen fixation by G. max.

7.
Physiol Plant ; 166(4): 894-908, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30414178

RESUMEN

Eucalyptus grandis is the most widely planted tree species worldwide and can face severe drought during the initial months after planting because the root system is developing. A complete randomized design was used to study the effects of two water regimes (well-watered and water-stressed) and phosphorus (P) applications (with and without P) on the morphological and physio-biochemical responses of E. grandis. Drought had negative effects on the growth and metabolism of E. grandis, as indicated by changes in morphological traits, decreased net photosynthetic rates (Pn ), pigment concentrations, leaf relative water contents (LRWCs), nitrogenous compounds, over-production of reactive oxygen species (ROS) and higher lipid peroxidation. However, E. grandis showed effective drought tolerance strategies, such as reduced leaf area and transpiration rate (E), higher accumulation of soluble sugars and proline and a strong antioxidative enzyme system. P fertilization had positive effects on well-watered seedlings due to improved growth and photosynthesis, which indicated the high P requirements during the initial E. grandis growth stage. In drought-stressed seedlings, P application had no effects on the morphological traits, but it significantly improved the LRWC, Pn , quantum efficiency of photosystem II (Fv /Fm ), chlorophyll pigments, nitrogenous compounds and reduced lipid peroxidation. P fertilization improved E. grandis seedling growth under well-watered conditions but also ameliorated some leaf physiological traits under drought conditions. The effects of P fertilization are mainly due to the enhancement of plant N nutrition. Therefore, P can be used as a fertilizer to improve growth and production in the face of future climate change.


Asunto(s)
Eucalyptus/efectos de los fármacos , Eucalyptus/metabolismo , Fósforo/farmacología , Plantones/efectos de los fármacos , Plantones/metabolismo , Clorofila/metabolismo , Sequías , Peroxidación de Lípido/efectos de los fármacos , Fotosíntesis/efectos de los fármacos , Transpiración de Plantas/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo
8.
Sci Rep ; 8(1): 15996, 2018 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-30375489

RESUMEN

A complete randomized design was implemented with two watering regimes (extreme rainfall and control) and three different plant combinations (Zanthoxylum bungeanum, Z. bungeanum + Capsicum annum, Z. bungeanum + Glycine max) in order to assess the morphological and physio-biochemical responses of focal and neighbor plants. The results indicated that, extreme rainfall had significantly negative impacts on Z. bungeanum in three intercropping systems. However, intercropping with G. max improved the transpiration rate (Tr) and stomatal conductance (Gs), raised leaf relative water content (LRWC), increased chlorophyll a (Chl a) and carotenoid (Car) content, and enhanced the superoxide dismutase activity (SOD) of Z. bungeanum. After recovery, the Z. bungeanum + G. max mixed culture significantly increased soil NO3--N, improved the intercellular carbon dioxide concentration (Ci) and Tr, upregulated soluble sugar and proline, and enhanced hydrogen peroxidase activity (CAT). Moreover, the higher root biomass of G. max provided much more nitrogen for Z. bungeanum via the return of organic matter. However, intercropping with C. annum significantly increased active oxygen (ROS). Compared with neighboring species, in intercropping systems, G. max could have improved the tolerance of the focal species Z. bungeanum in response to extreme rainfall and its recovery after extreme rainfall.


Asunto(s)
Ecosistema , Fabaceae/fisiología , Lluvia , Zanthoxylum/fisiología , Peroxidación de Lípido , Nitrógeno/química , Fotosíntesis , Hojas de la Planta/química , Carácter Cuantitativo Heredable , Especies Reactivas de Oxígeno/metabolismo , Suelo/química
9.
Medicine (Baltimore) ; 97(39): e12446, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30278523

RESUMEN

To develop and validate the prognosis model of hypertensive intracerebral hemorrhage based on admission characteristics, which would be applied to predict the 3-month outcome.For developing the prognosis models, we studied data from 325 patients with retrospectively consecutive hypertensive intracerebral hemorrhage admitted between 2012 and 2016. The predictive value of admission characteristics was tested in logistic regression models, presenting 3-month outcome as the primary outcome. The performance of the models was tested by discrimination and calibration. After development, internal and external validations were used to test the function.The multivariate analysis of logistic regression indicated that age, Glasgow coma scale score, pupillary light reflex, hypoxemia, intracerebral hemorrhage volume, blood glucose, and D-dimer level were independent factors of the hypertensive intracerebral hemorrhage prognosis model. The prognosis model based on those admission risk factors worked well. The receiver operating characteristic curve was used to analyze the discriminant ability of model A, model A + B, and model A + B + C. Specifically, the area under the receiver operating characteristic curve increased from 0.816 (model A; 95% CI, 0.760-0.872) to 0.913 (model A + B + C; 95% CI, 0.881-0.946), and the models were not overoptimistic and were applicably confirmed by internal and external validations respectively.This prognosis model could be used to predict the prognosis of patients with hypertensive intracerebral hemorrhage early, simply and accurately, contributing to the clinical treatment eventually.


Asunto(s)
Hemorragia Cerebral/mortalidad , Hipertensión/complicaciones , Hemorragia Intracraneal Hipertensiva/sangre , Hemorragia Intracraneal Hipertensiva/mortalidad , Anciano , Anciano de 80 o más Años , Glucemia/análisis , Hemorragia Cerebral/diagnóstico por imagen , Hemorragia Cerebral/fisiopatología , Femenino , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Escala de Coma de Glasgow/normas , Hospitalización/estadística & datos numéricos , Humanos , Hipertensión/epidemiología , Hipertensión/mortalidad , Hipoxia/mortalidad , Hipoxia/fisiopatología , Hemorragia Intracraneal Hipertensiva/diagnóstico por imagen , Hemorragia Intracraneal Hipertensiva/metabolismo , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Valor Predictivo de las Pruebas , Pronóstico , Reflejo Pupilar/fisiología , Estudios Retrospectivos , Factores de Riesgo , Tomografía Computarizada por Rayos X/métodos
10.
Sci Rep ; 8(1): 9992, 2018 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-29968765

RESUMEN

Straw mulching is an effective conservation tillage tool that utilizes waste resources and reduces environmental pollution. To determine the optimal levels of quality, placement and quantity of straw mulching, we performed a field experiment that used the Box-Behnken design combined with response surface methodology. The treatments designed for walnut saplings (Juglans regia) considered three independent variables: quality, placement, and quantity of straw mulching. Tree height of walnut saplings (THW) and net photosynthesis rate (NPR) were used as the response variables in a full, quadratic polynomial model. Analysis of variance (ANOVA) results showed that the selected models were significant (P < 0.05), expressing ideal relationships between the independent and dependent variables (R2 ≥ 0.9225). The optimum conditions for the THW and NPR responses were determined to be a straw mulching quality which mixed rice and rapeseed straws, a straw mulching placement which covered the entire soil surface of experimental plots, and a straw mulching quantity applied as 3 kg/m2 (i.e., the low level). This optimized scheme of straw mulching combinations offers an alternate choice for optimizing the growth and potential yield of walnut saplings, but practical field experiments should also be carried out to obtain more site-specific results.


Asunto(s)
Agricultura/métodos , Juglans/crecimiento & desarrollo , China , Contaminación Ambiental/análisis , Fotosíntesis , Suelo/química , Análisis Espacial , Agua/análisis
11.
Sci Rep ; 8(1): 5644, 2018 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-29618772

RESUMEN

Alnus cremastogyne, a broad-leaved tree endemic to south-western China, has both commercial and restoration importance. However, little is known of its morphological, physiological and biochemical responses to drought and phosphorous (P) application. A randomized experimental design was used to investigate how drought affected A. cremastogyne seedlings, and the role that P applications play in these responses. Drought had significant negative effects on A. cremastogyne growth and metabolism, as revealed by reduced biomass (leaf, shoot and root), leaf area, stem diameter, plant height, photosynthetic rate, leaf relative water content, and photosynthetic pigments, and a weakened antioxidative defence mechanism and high lipid peroxidation level. However, the reduced leaf area and enhanced osmolyte (proline and soluble sugars) accumulation suggests drought avoidance and tolerance strategies in this tree. Applying P significantly improved the leaf relative water content and photosynthetic rate of drought-stressed seedlings, which may reflect increased anti-oxidative enzyme (superoxide dismutase, catalase and peroxidase) activities, osmolyte accumulation, soluble proteins, and decreased lipid peroxidation levels. However, P had only a slight or negligible effect on the well-watered plants. A. cremastogyne is sensitive to drought stress, but P facilitates and improves its metabolism primarily via biochemical and physiological rather than morphological adjustments, regardless of water availability.


Asunto(s)
Antioxidantes/metabolismo , Sequías , Peroxidación de Lípido , Ósmosis , Fósforo/administración & dosificación , Fotosíntesis , Agua/química , Alnus , Biomasa , Clorofila/metabolismo , Hojas de la Planta , Superóxido Dismutasa/metabolismo
12.
Front Plant Sci ; 8: 1561, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28955356

RESUMEN

Phoebe zhennan (Gold Phoebe) is a threatened tree species in China and a valuable and important source of wood and bioactive compounds used in medicine. Apart from anthropogenic disturbances, several biotic constraints currently restrict its growth and development. However, little attention has been given to building adaptive strategies for its conservation by examining its morphological and physio-biochemical responses to drought stress, and the role of fertilizers on these responses. A randomized experimental design was used to investigate the effects of two levels of irrigation (well-watered and drought-stressed) and phosphorous (P) fertilization treatment (with and without P) to assess the morphological and physio-biochemical responses of P. zhennan seedlings to drought stress. In addition, we evaluated whether P application could mitigate the negative impacts of drought on plant growth and metabolism. Drought stress had a significant negative effect on the growth and metabolic processes of P. zhennan. Despite this, reduced leaf area, limited stomatal conductance, reduced transpiration rate, increased water use efficiency, enhanced antioxidant enzymes activities, and osmolytes accumulation suggested that the species has good adaptive strategies for tolerating drought stress. Application of P had a significant positive effect on root biomass, signifying its improved water extracting capacity from the soil. Moreover, P fertilization significantly increased leaf relative water content, net photosynthetic rate, and maximal quantum efficiency of PSII under drought stress conditions. This may be attributable to several factors, such as enhanced root biomass, decreased malondialdehyde content, and the up-regulation of chloroplast pigments, osmolytes, and nitrogenous compounds. However, P application had only a slight or negligible effect on the growth and metabolism of well-watered plants. In conclusion, P. zhennan has a strong capability for drought resistance, while P application facilitates and improves drought tolerance mostly through physio-biochemical adjustments, regardless of water availability. It is imperative to explore the underlying metabolic mechanisms and effects of different levels of P fertilization on P. zhennan under drought conditions in order to design appropriate conservation and management strategies for this species, which is at risk of extinction.

13.
Phytother Res ; 31(2): 202-264, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28093828

RESUMEN

Cancer is a serious health problem and the second leading cause of death around the globe. Present review is an attempt to provide utmost information based on ethno-pharmacological and toxicological aspects of anti-cancer plants of the world. A total of 276 articles published in English journals and containing maximum ethnomedicinal information were reviewed using several data sources such as; Google scholar, Web of Science, Scopus, PubMed and floras of different countries. A total of 199 anti-cancer plants were recorded in present review and results indicated that traditional medicines are mostly being use in developing countries for cancer treatment. Traditionally and scientifically skin and breast cancer types gained more focus. Seventy plants were reportedly analyzed for in-vitro activities while 32 plants were having in-vivo reports. Twenty nine pure compounds (mostly phenolic) were reportedly isolated from anti-cancer plants and tested against different cancer cell lines. Inspite having better efficiency of ethnomedicines as compared to synthetic drugs, several plants have also shown toxic effects on living system. Therefore, we invite researchers attention to carry out detailed ethno-pharmacological and toxicological studies on un-explored anti-cancer plants in order to provide reliable knowledge to the patients and develop novel anti-cancer drugs. Copyright © 2017 John Wiley & Sons, Ltd.


Asunto(s)
Antineoplásicos/uso terapéutico , Etnofarmacología/métodos , Medicina Tradicional/métodos , Neoplasias/tratamiento farmacológico , Fitoterapia/métodos , Humanos
14.
PLoS One ; 11(12): e0167037, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27911906

RESUMEN

Environmental pollution with heavy metals is a serious issue worldwide posing threats to humans, animals and plants and to the stability of overall ecosystem. Chromium (Cr) is one of most hazardous heavy metals with a high carcinogenic and recalcitrant nature. Aim of the present study was to select low-cost biosorbent using wheat straw and Eupatorium adenophorum through simple carbonization process, capable of removing Cr (VI) efficiently from wastewater. From studied plants a low cost adsorbent was prepared for removing Cr (VI) from aqueous solution following very simple carbonization method excluding activation process. Several factors such as pH, contact time, sorbent dosage and temperature were investigated for attaining ideal condition. For analysis of adsorption equilibrium isotherm data, Langmuir, Freundlich and Temkin models were used while pseudo-first-order, pseudo-second-order, external diffusion and intra-particle diffusion models were used for the analysis of kinetic data. The obtained results revealed that 99.9% of Cr (VI) removal was observed in the solution with a pH of 1.0. Among all the tested models Langmuir model fitted more closely according to the data obtained. Increase in adsorption capacity was observed with increasing temperature revealing endothermic nature of Cr (VI). The maximum Cr (VI) adsorption potential of E. adenophorum and wheat straw was 89.22 mg per 1 gram adsorbent at 308K. Kinetic data of absorption precisely followed pseudo-second-order model. Present study revealed highest potential of E. adenophorum and wheat straw for producing low cost adsorbent and to remove Cr (VI) from contaminated water.


Asunto(s)
Ageratina/crecimiento & desarrollo , Compuestos de Cromo/metabolismo , Modelos Biológicos , Aguas Residuales/microbiología , Microbiología del Agua , Contaminantes Químicos del Agua/metabolismo , Concentración de Iones de Hidrógeno , Triticum , Purificación del Agua/métodos
15.
Sci Rep ; 6: 37662, 2016 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-27874081

RESUMEN

An agroforestry experiment was conducted that involved four planting systems: monoculture of the focal species Zanthoxylum bungeanum and mixed cultures of Z. bungeanum and Capsicum annuum, Z. bungeanum and Medicago sativa and Z. bungeanum and Glycine max. Soil microbial food web (microorganisms and nematodes) was investigated under manipulated extreme rainfall in the four planting systems to assess whether presence of neighbor species alleviated the magnitude of extreme rainfall on nutrient uptake of the focal species by increasing the stability of soil food web. Our results indicate that in the focal species and G. max mixed culture, leaf nitrogen contents of the focal species were higher than in the monoculture and in the other mixed cultures under extreme rainfall. This result was mainly due to the significant increase under extreme rainfall of G. max species root biomass, resulting in enhanced microbial resistance and subsequent net nitrogen mineralization rate and leaf nitrogen uptake for the focal species. Differences in functional traits of neighbors had additive effects and led to a marked divergence of soil food-web resistance and nutrient uptake of the focal species. Climate change can indirectly alleviate focal species via its influence on their neighbors.


Asunto(s)
Cadena Alimentaria , Plantas/microbiología , Lluvia , Microbiología del Suelo , Animales , Biomasa , Minerales/análisis , Nematodos/fisiología , Nitrógeno/análisis , Hojas de la Planta/metabolismo , Raíces de Plantas/metabolismo , Plantas/parasitología , Suelo/química
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