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1.
Water Res ; 188: 116525, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33091803

RESUMEN

Lake Erie harmful algal blooms and hypoxia are two major environmental problems, and have severe impacts on human health, aquatic ecosystems, and the economy. However, little is known about internal loading of phosphorus (P) from sediments, which pose a challenge for assessing the efficacy of current conservation measures on the improvement of lake water quality. A modified Hedley's extraction procedure was employed to analyze representative sediment samples collected from the Lake Erie basin for assessing sedimentary P stock, potential availability for release into lake water, and internal P loading. Inorganic and organic P in the sediments were characterized by sequential extractions in H2O, 0.5 M NaHCO3, 0.1 M NaOH, and 1.0 M HCl, respectively. In the 0 - 10 cm sediment, total P stock was 172, 191, and 170 metric tons km-2 in the western, central, and eastern basins, respectively. Sedimentary P seems unlikely to contribute to internal P loading in the western basin, while in the eastern basin it can potentially contribute to an internal loading of 359 metric tons P yr-1. In the central basin, 41% of organic P, 15% of non-HCl extractable inorganic P, and 9.7% of residual P in the 0 - 10 cm sediment is potentially available for release into lake water; in the 10 - 20 cm sediment, organic P extracted by NaHCO3 and NaOH is also partially available. The central basin potentially contributes to internal P loading at a total amount of 10,599 metric tons yr-1. Internal P loading may not contribute to HABs in the western basin, but it can cause and maintain hypoxia in the central basin and delay the recovery of lake water quality for a lengthy time period in response to external P reduction measures.


Asunto(s)
Lagos , Fósforo , Ecosistema , Monitoreo del Ambiente , Eutrofización , Sedimentos Geológicos , Humanos , Fósforo/análisis
2.
J Environ Qual ; 48(1): 39-46, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30640351

RESUMEN

Simulation of phosphorus (P) transfer from manured agricultural lands to water bodies via surface runoff and subsurface drainage is potentially of great help in evaluating the risks and effects of eutrophication under a range of best management practice scenarios. However, it remains a challenge since few models are capable of providing a reasonably accurate prediction of P losses under manure treatment. The Environmental Policy Integrated Climate (EPIC) model was applied to simulate the impacts on dissolved reactive P (DRP) losses through surface runoff and subsurface drainage from a solid cattle manure-amended corn ( L.)-soybean [ (L.) Merr.] rotation on a clay loam soil (Vertisol) located in the Lake Erie region. Simulations of DRP loss in surface runoff and tile drainage were satisfactory; however, EPIC did not consider DRP loss directly from manure, weakening its accuracy in the prediction of DRP loss in surface runoff. Having previously drawn on EPIC-predicted surface runoff to initiate SurPhos (Surface Phosphorus and Runoff Model) predictions of DRP losses strictly in surface runoff, no comparison had been made of differences in manure application impacts on EPIC- or SurPhos-predicted DRP losses-accordingly, this was assessed. The SurPhos improved the estimation of DRP loss in surface runoff (Nash-Sutcliffe coefficient, 0.53), especially when large rain events occurred immediately after or within 6 wk of manure application. Generally, EPIC can capture the impacts of manure application on DRP loss in surface runoff and subsurface drainage; however, coupling of the EPIC and SurPhos models increased the accuracy of simulation of runoff DRP losses.


Asunto(s)
Estiércol , Fósforo , Agricultura , Animales , Bovinos , Lluvia , Suelo , Movimientos del Agua
3.
Med J Malaysia ; 74(6): 499-503, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31929475

RESUMEN

INTRODUCTION: Carpal tunnel syndrome (CTS) is the commonest median nerve entrapment neuropathy of the hand, up to 90% of all nerve compression syndromes. The disease is often treated with conservative measures or surgery. The senior author initially intended to treat his own neurosurgical patients concurrently diagnosed with carpal tunnel syndrome in 2014, subsequently, he began to pick up more referrals from the primary healthcare group over the years. This has led to the setup of a peripheral and spine clinic to act as a hub of referrals. OBJECTIVE: Department of Neurosurgery Sarawak aimed to evaluate the surgical outcome of carpal tunnel release done over five years. METHODS: The carpal tunnel surgeries were done under local anaesthesia (LA) given by neurosurgeons (Bupivacaine 0.5% or Lignocaine 2%). Monitored anaesthesia care (MAC) was later introduced by our hospital neuroanaesthetist in the beginning of 2018 (Target-controlled infusion propofol and boluses of fentanyl). We looked into our first 17 cases and compared these to the two anaesthesia techniques (LA versus MAC + LA) in terms of patient's pain score based on visual analogue scale (VAS). RESULTS: Result showed MAC provided excellent pain control during and immediately after the surgery. None experienced anaesthesia complications. There was no difference in pain control at post-operation one month. Both techniques had equal good clinical outcome during patients' clinic follow up. CONCLUSION: Neurosurgeons provide alternative route for CTS patients to receive surgical treatment. Being a designated pain free hospital, anaesthetist collaboration in carpal tunnel surgery is an added value and improves patients overall experience and satisfaction.


Asunto(s)
Anestesia Local/métodos , Síndrome del Túnel Carpiano/cirugía , Neurocirujanos , Procedimientos Neuroquirúrgicos/métodos , Manejo del Dolor/métodos , Adulto , Síndrome del Túnel Carpiano/diagnóstico , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo , Resultado del Tratamiento
4.
J Environ Qual ; 47(2): 191-202, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29634786

RESUMEN

Environmental indicators are powerful tools for tracking environmental changes, measuring environmental performance, and informing policymakers. Many diverse environmental indicators, including agricultural environmental indicators, are currently in use or being developed. This special collection of technical papers expands on the peer-reviewed literature on environmental indicators and their application to important current issues in the following areas: (i) model-derived indicators to indicate phosphorus losses from arable land to surface runoff and subsurface drainage, (ii) glutathione-ascorbate cycle-related antioxidants as early-warning bioindicators of polybrominated diphenyl ether toxicity in mangroves, and (iii) assessing the effectiveness of using organic matrix biobeds to limit herbicide dissipation from agricultural fields, thereby controlling on-farm point-source pollution. This introductory review also provides an overview of environmental indicators, mainly for agriculture, with examples related to the quality of the agricultural soil-water-air continuum and the application of model-derived indicators. Current knowledge gaps and future lines of investigation are also discussed. It appears that environmental indicators, particularly those for agriculture, work efficiently at the field, catchment, and local scales and serve as valuable metrics of system functioning and response; however, these indicators need to be refined or further developed to comprehensively meet community expectations in terms of providing a consistent picture of relevant issues and/or allowing comparisons to be made nationally or internationally.


Asunto(s)
Agricultura , Contaminantes Ambientales/análisis , Contaminación del Aire , Monitoreo del Ambiente , Herbicidas , Fósforo , Suelo , Agua
5.
J Environ Qual ; 47(2): 318-325, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29634797

RESUMEN

Forms (e.g., liquid and solid) of manure influence the risk of P loss after land application. The objective of this study was to investigate the effects of P-based application of various forms of cattle manure (liquid, LCM; or solid, SCM) or inorganic P as triple superphosphate (IP) on soil P losses in tile drainage water. A 4-yr field experiment was conducted in a clay loam soil with a corn ( L.)-soybean [ (L.) Merr.] rotation in the Lake Erie basin. Over the 4 yr, the dissolved reactive P (DRP) flow-weighted mean concentration (FWMC) in tile drainage water was greater under SCM fertilization than under either IP or LCM fertilization. Despite its lower value on an annual basis, DRP FWMC rose dramatically immediately after LCM application. However, the differences in DRP FWMC did not result in detectable differences in DRP loads. Regarding particulate P and total P losses during the 4 yr, they were 68 and 47%, respectively, lower in the soils amended with SCM than in those with IP, whereas both values were similar between IP and LCM treatments. Overall, the P contained in solid cattle manure was less prone to P loss after land application. Accordingly, the present results can provide a basis for manure storage and application of best management practices designed to reduce P losses and improve crop growth.


Asunto(s)
Estiércol , Fósforo/análisis , Agricultura , Animales , Bovinos , Suelo , Agua , Movimientos del Agua
6.
J Environ Qual ; 47(2): 203-211, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29634805

RESUMEN

Modeling soil phosphorus (P) losses by surface and subsurface flow pathways is essential in developing successful strategies for P pollution control. We used the ICECREAM model to simultaneously simulate P losses in surface and subsurface flow, as well as to assess effectiveness of field practices in reducing P losses. Monitoring data from a mineral-P-fertilized clay loam field in southwestern Ontario, Canada, were used for calibration and validation. After careful adjustment of model parameters, ICECREAM was shown to satisfactorily simulate all major processes of surface and subsurface P losses. When the calibrated model was used to assess tillage and fertilizer management scenarios, results point to a 10% reduction in total P losses by shifting autumn tillage to spring, and a 25.4% reduction in total P losses by injecting fertilizer rather than broadcasting. Although the ICECREAM model was effective in simulating surface and subsurface P losses when thoroughly calibrated, further testing is needed to confirm these results with manure P application. As illustrated here, successful use of simulation models requires careful verification of model routines and comprehensive calibration to ensure that site-specific processes are accurately represented.


Asunto(s)
Fósforo/análisis , Contaminantes del Agua/análisis , Agricultura , Canadá , Fertilizantes , Estiércol , Movimientos del Agua
7.
Sci Rep ; 6: 30010, 2016 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-27460640

RESUMEN

Lignosus rhinocerotis (Tiger milk mushroom) is an important folk medicine for indigenous peoples in Southeast Asia. We previously reported its de novo assembled 34.3 Mb genome encoding a repertoire of proteins including a putative bioactive fungal immunomodulatory protein. Here we report the cDNA of this new member (FIP-Lrh) with a homology range of 54-64% to FIPs from other mushroom species, the closest is with FIP-glu (LZ-8) (64%) from Ganoderma lucidum. The FIP-Lrh of 112 amino acids (12.59 kDa) has a relatively hydrophobic N-terminal. Its predicted 3-dimensional model has identical folding patterns to FIP-fve and contains a partially conserved and more positively charged carbohydrates binding pocket. Docking predictions of FIP-Lrh on 14 glycans commonly found on cellular surfaces showed the best binding energy of -3.98 kcal/mol to N-acetylgalactosamine and N-acetylglucosamine. Overexpression of a 14.9 kDa soluble 6xHisFIP-Lrh was achieved in pET-28a(+)/BL21 and the purified recombinant protein was sequence verified by LC-MS/MS (QTOF) analysis. The ability to haemagglutinate both mouse and human blood at concentration ≥0.34 µM, further demonstrated its lectin nature. In addition, the cytotoxic effect of 6xHisFIP-Lrh on MCF-7, HeLa and A549 cancer cell lines was detected at IC50 of 0.34 µM, 0.58 µM and 0.60 µM, respectively.


Asunto(s)
Agaricales/inmunología , Eritrocitos/efectos de los fármacos , Proteínas Fúngicas/inmunología , Hemaglutinación/efectos de los fármacos , Factores Inmunológicos/metabolismo , Células A549 , Agaricales/genética , Secuencia de Aminoácidos/genética , Animales , Agregación Celular/fisiología , Línea Celular Tumoral , Proteínas Fúngicas/genética , Células HeLa , Humanos , Factores Inmunológicos/genética , Células MCF-7 , Ratones , Simulación del Acoplamiento Molecular , Pliegue de Proteína
8.
Artículo en Inglés | MEDLINE | ID: mdl-22454675

RESUMEN

Lignosus rhinocerus, the tiger milk mushroom, is one of the most important medicinal mushrooms used by the indigenous people of Southeast Asia and China. It has been used to treat breast cancer. A cold water extract (LR-CW) prepared from the sclerotia of L. rhinocerus cultivar was found to exhibit antiproliferative activity against human breast carcinoma (MCF-7) and human lung carcinoma (A549), with IC(50) of 96.7 µg/mL and 466.7 µg/mL, respectively. In comparison, LR-CW did not show significant cytotoxicity against the two corresponding human normal cells, 184B5 (human breast cell) and NL 20 (human lung cell). DNA fragmentation studies suggested that the cytotoxic action of LR-CW against cancer cells is mediated by apoptosis. Sephadex G-50 gel filtration fractionation of LR-CW yielded a high-molecular-weight and a low-molecular-weight fraction. The high-molecular-weight fraction contains mainly carbohydrate (68.7%) and small amount of protein (3.6%), whereas the low-molecular-weight fraction contains 31% carbohydrate and was devoid of protein. Only the high-molecular-weight fraction exhibited antiproliferative activity against cancer cells, with IC(50) of 70.0 µg/mL and 76.7 µg/mL, respectively. Thus, the cytotoxic action of the LR-CW is due to the high-molecular-weight fraction, either the proteins or protein-carbohydrate complex.

9.
J Environ Qual ; 39(5): 1771-81, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21043282

RESUMEN

Phosphorus (P) loss from agricultural land in surface runoff can contribute to eutrophication of surface water. This study was conducted to evaluate a range of environmental and agronomic soil P tests as indicators of potential soil surface runoff dissolved reactive P (DRP) losses from Ontario soils. The soil samples (0- to 20-cm depth) were collected from six soil series in Ontario, with 10 sites each to provide a wide range of soil test P (STP) values. Rainfall simulation studies were conducted following the USEPA National P Research Project protocol. The average DRP concentration (DRP30) in runoff water collected over 30 min after the start of runoff increased (p < 0.001) in either a linear or curvilinear manner with increases in levels of various STPs and estimates of degree of soil P saturation (DPS). Among the 16 measurements of STPs and DPSs assessed, DPS(M3) 2 (Mehlich-3 P/[Mehlich-3 Al + Fe]) (r2 = 0.90), DPS(M3)-3 (Mehlich-3 P/Mehlich-3 Al) (r2 = 0.89), and water-extractable P (WEP) (r2 = 0.89) had the strongest overall relationship with runoff DRP30 across all six soil series. The DPS(M3)-2 and DPS(M3)-3 were equally accurate in predicting runoff DRP30 loss. However, DPS(M3)-3 was preferred as its prediction of DRP30 was soil pH insensitive and simpler in analytical procedure, ifa DPS approach is adopted.


Asunto(s)
Fósforo/análisis , Suelo/análisis , Contaminantes del Agua/análisis , Ontario , Solubilidad
11.
Singapore Med J ; 48(4): 287-90, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17384873

RESUMEN

INTRODUCTION: This study aims to describe the preferences of ophthalmic anaesthesia for cataract extraction among ophthalmologists in Singapore. METHODS: A nationwide questionnaire survey of all cataract surgeons in institutional and private practice in Singapore was conducted in August 2004. RESULTS: The response rate was 61.1 percent (88 out of 144 eligible ophthalmologists surveyed). Phacoemulsification was the preferred surgical technique for 92 percent of the respondents while extra-capsular cataract extraction was preferred by eight percent. For all surgeons performing phacoemulsification, the anaesthesia technique of choice was peribulbar anaesthesia for 43 percent, topical anaesthesia for 42 percent, retrobulbar anaesthesia for 13 percent, and sub-tenons and general anaesthesia for one percent each of the respondents. For all the surgeons performing extra-capsular cataract extraction, the preferred anaesthetic technique was peribulbar anaesthesia for 69 percent, retrobulbar anaesthesia for 30 percent and sub-tenons anaesthesia for one percent of the respondents. The surgeons' main reasons for choosing a specific anaesthesia modality for their surgery were patient comfort and surgeon's choice. The majority of surgeons used mild sedation and monitored anaesthesia care for their cataract surgeries. CONCLUSION: Peribulbar anaesthesia is currently the preferred anaesthesia technique for both phacoemulsification and extra-capsular cataract extraction in Singapore. Topical anaesthesia closely follows peribulbar anaesthesia as a preferred choice for phacoemulsification.


Asunto(s)
Anestesia Local/métodos , Extracción de Catarata/métodos , Oftalmología/métodos , Pautas de la Práctica en Medicina , Anestesia Local/estadística & datos numéricos , Humanos , Pautas de la Práctica en Medicina/estadística & datos numéricos , Singapur , Encuestas y Cuestionarios
12.
Eye (Lond) ; 21(9): 1162-7, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16710431

RESUMEN

PURPOSE: To describe what patients expect to see and the visual sensations they actually experience during phacoemulsification under topical anaesthesia. We also sought to determine if patients find their intraoperative visual experience frightening and the factors associated with this. MATERIALS AND METHODS: Ninety-eight patients who underwent phacoemulsification and intraocular lens implantation under topical anaesthesia were interviewed preoperatively on what they expected to see with their operated eye during surgery and again postoperatively on what they actually saw. No patient received counselling about possible intraoperative visual sensations. A logistic (multivariate) regression model was used for statistical analysis. RESULTS: Preoperatively, 36 patients (36.7%) expected at least light perception, 38 (38.8%) expected no light perception, and 24 (24.5%) were unsure what to expect. Some patients also expected a variety of different visual sensations. Postoperatively, all patients (100%) reported seeing light intraoperatively and many experienced various other visual sensations. Nineteen patients (19.4%) found their visual experience frightening. The following factors were statistically associated with a frightening visual experience: preoperative anxiety, previous cataract surgery in the fellow eye, experiencing an intraoperative increase in clarity, not seeing movement intraoperatively, and not knowing what to expect. CONCLUSIONS: The majority of patients in this study either expected that they would see nothing at all during the surgery or were unsure of what to expect. All patients subsequently saw at least some light, and many perceived various other visual sensations that were frightening to nearly one in five patients. Preoperative counselling should inform about possible intraoperative visual experience.


Asunto(s)
Anestesia Local , Actitud Frente a la Salud , Facoemulsificación , Percepción Visual , Adulto , Anciano , Anciano de 80 o más Años , Ansiedad/psicología , Consejo , Miedo/psicología , Femenino , Humanos , Periodo Intraoperatorio , Implantación de Lentes Intraoculares , Masculino , Persona de Mediana Edad , Educación del Paciente como Asunto , Cuidados Preoperatorios/métodos , Factores de Riesgo
13.
Genet Soc Gen Psychol Monogr ; 126(2): 241-60, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10846623

RESUMEN

Trust in supervisor and trust in organization are argued to be distinct but related constructs, each with its own set of antecedents and outcomes. Empirical field results supported the proposition. Although trust in supervisor and trust in organization were positively and significantly correlated, trust in supervisor was more strongly associated with proximal variables (ability, benevolence, and integrity of supervisor), whereas trust in organization was more strongly correlated with global variables (perceived organizational support and justice). This conclusion held despite the inclusion of proximal variables in the regression on trust in organization and the inclusion of global variables in the regression on trust in supervisor. In addition to the differential antecedents of trust in supervisor and trust in organization, the outcomes for both variables were different. Trust in supervisor was related to increased innovative behavior and satisfaction with supervisor, and trust in organization was related to higher organizational commitment and lower intention to leave. Therefore, the authors provide clear preliminary data on the distinctiveness of trust in supervisor and trust in organization. One implication of this set of results is that organizations should adopt a more holistic approach in building trust, which can be achieved by focusing on the various constituents of the organization and the various levels (e.g., the supervisor level and the organizational level).


Asunto(s)
Relaciones Interpersonales , Administración de Personal , Revelación de la Verdad , Humanos , Cultura Organizacional
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