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1.
Environ Sci Pollut Res Int ; 26(16): 16125-16144, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30972670

ABSTRACT

Metropolitan areas may suffer with increase of air pollution due to the growth of urbanization, transportation, and industrial sectors. The Metropolitan Area of Vitória (MAV) in Brazil is facing air pollution problems, especially because of the urbanization of past years and of having many industries inside the metropolitan area. Developing air quality system is crucial to understand the air pollution mechanism over these areas. However, having a good input dataset for applying on photochemical models is hard and requires quite of research. One input file for air quality modeling which can play a key role on results is the lateral boundary conditions (LBC). This study aimed to investigate the influence of LBC over CMAQ simulation for particulate matter and ozone over MAV by applying four different methods as LBC during August 2010. The first scenario (M1) is based on a fixed, time-independent boundary conditions with zero concentrations for all pollutants; the second scenario (M2) used a fixed, time-independent concentration values, with average values from local monitoring stations; the third CMAQ nesting scenario (M3) used the nested boundary conditions varying with time from a previous simulation with CMAQ over a larger modeling domain, centered on MAV; and finally, the fourth GEOS-Chem scenario (M4) used the boundary conditions varying with time from simulations of global model GEOS-Chem. All scenarios runs are based on the same meteorology conditions and pollutant emissions. The air quality simulations were made over a domain 61 × 79 km centered on coordinates - 20.25° S, - 40.28° W with a resolution of 1 km. The results were evaluated with the measured data from the local monitoring stations. Overall, significant differences on concentrations and number of chemical species between the LBC scenarios are shown across all LBC scenarios. The M3 and M4 dynamic LBC scenarios showed the best performances over ozone estimates while M1 and M2 had poor performance. Although no LBC scenarios do not seem to have a great influence on total PM10 and PM2.5 concentrations, individual PM2.5 species like Na, NO3-, and NH4+concentrations are influenced by the dynamic LBC approach, since those hourly individual PM2.5 species from CMAQ nesting approach (M3) and GEOS-Chem model (M4) were used as an input to LBC.


Subject(s)
Air Pollution/analysis , Models, Theoretical , Ozone/analysis , Air Pollutants/analysis , Brazil , Cities , Environmental Monitoring/methods , Industrial Development , Meteorology/methods , Particulate Matter/analysis , Photochemical Processes
2.
Front Chem ; 6: 236, 2018.
Article in English | MEDLINE | ID: mdl-30191147

ABSTRACT

Due to the cost-effectiveness of sodium source, sodium-ion batteries (SIBs) have attracted considerable attention. However, SIBs still have some challenges in competing with lithium-ion batteries for practical applications. Particularly, the high rate capability and cycling stability are posing big problems for SIBs. Here, nitrogen-doped carbon-coated WS2 nanosheets (WS2/NC) were successfully synthesized by a high-temperature solution method, followed by carbonization of polypyrrole. When used as anode electrodes for SIBs, WS2/NC composite exhibited high-rate capacity at 386 and 238.1 mAh g-1 at 50 and 2,000 mA g-1, respectively. Furthermore, even after 400 cycle, the composite electrode could still deliver a capacity of ~180.1 mAh g-1 at 1,000 mA g-1, corresponding to a capacity loss of 0.09% per cycle. The excellent electrochemical performance could be attributed to the synergistic effect of the highly conductive nature of the nitrogen-doped carbon-coating and WS2 nanosheets. Results showed that the WS2/NC nanosheets are promising electrode materials for SIBs application.

3.
J Vet Intern Med ; 31(4): 1123-1131, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28703446

ABSTRACT

BACKGROUND: In the last decade, a disorder characterized by episodes of involuntary movements and dystonia has been recognized in Border Terriers. OBJECTIVES: To define clinical features of paroxysmal dyskinesia (PD) in a large number of Border Terriers and to study the genetics of the disease. ANIMALS: 110 affected and 128 unaffected client-owned Border Terriers. METHODS: A questionnaire regarding clinical characteristics of PD was designed at Utrecht University and the University of Helsinki. Thirty-five affected Border Terriers underwent physical examination and blood testing (hematology and clinical biochemistry). Diagnostic imaging of the brain was performed in 17 affected dogs and electroencephalograms (EEG) between episodes were obtained in 10 affected dogs. A genomewide association study (GWAS) was performed with DNA of 110 affected and 128 unaffected dogs. RESULTS: One hundred forty-seven questionnaires were included in the study. The most characteristic signs during episodes were dystonia, muscle fasciculations, and falling over. The majority of owners believed that their dogs remained conscious during the episodes. A beneficial effect of anti-epileptic therapy was observed in 29 of 43 dogs. Fifteen owners changed their dogs' diet to a hypoallergenic, gluten-free diet, and all reported reasonable to good improvement of signs. Clinical examinations and diagnostic test results were unremarkable. The GWAS did not identify significantly associated chromosome regions. CONCLUSIONS AND CLINICAL IMPORTANCE: The survey results and EEG studies provided further evidence that the observed syndrome is a PD rather than epilepsy. Failure to achieve conclusive results by GWAS indicates that inheritance of PD in Border Terriers probably is complex.


Subject(s)
Chorea/veterinary , Dog Diseases/diagnosis , Animals , Brain/diagnostic imaging , Brain/physiopathology , Chorea/diagnosis , Chorea/epidemiology , Chorea/genetics , Dog Diseases/epidemiology , Dog Diseases/genetics , Dog Diseases/pathology , Dogs , Electroencephalography/veterinary , Female , Genome-Wide Association Study/veterinary , Male , Neuroimaging/veterinary
4.
Langmuir ; 25(19): 11947-54, 2009 Oct 06.
Article in English | MEDLINE | ID: mdl-19788234

ABSTRACT

Electrochemically active surface area (ECA) of a polycrystalline Pt electrode is measured from the pseudocapacitance (Cp) values that are associated with hydrogen underpotential deposition. The potential-dependent Cp values are extracted from the raw impedance data by removing the interferences coming from the double-layer charging and hydrogen evolution. Three different approaches have been made: (i) by using the proportionality between the capacitance and area of the capacitive peak on imaginary capacitance plots, (ii) by complex nonlinear least-squares (CNLS) fitting on both the imaginary and real part of complex capacitance with appropriate equivalent circuits, and (iii) by using the modified Kramers-Kronig (K-K) relation. The first approach is the simplest one for the Cp measurement but cannot be used in the hydrogen evolution region (<0.05 V vs RHE), whereas the measurement can be extended down to -0.01 V with the second method. The isotherm fitting on the Cp(E) profile shows that the saturation of adsorbed hydrogen is reached at -0.1 V vs RHE. Faster data acquisition is possible with the third approach since the data analysis can be made without the time-consuming low frequency data (<100 Hz). The roughness factor and ECA of the Pt electrode are calculated from the electric charge that is obtained by integrating the potential-dependent Cp values; the roughness factor (1.4-1.5) lies within the normal range for planar electrodes.

5.
Am J Bioeth ; 9(5): 31-6, 2009 May.
Article in English | MEDLINE | ID: mdl-19396681

ABSTRACT

The prospect of using cell-based interventions (CBIs) to treat neurological conditions raises several important ethical and policy questions. In this target article, we focus on issues related to the unique constellation of traits that characterize CBIs targeted at the central nervous system. In particular, there is at least a theoretical prospect that these cells will alter the recipients' cognition, mood, and behavior-brain functions that are central to our concept of the self. The potential for such changes, although perhaps remote, is cause for concern and careful ethical analysis. Both to enable better informed consent in the future and as an end in itself, we argue that early human trials of CBIs for neurological conditions must monitor subjects for changes in cognition, mood, and behavior; further, we recommend concrete steps for that monitoring. Such steps will help better characterize the potential risks and benefits of CBIs as they are tested and potentially used for treatment.


Subject(s)
Affect , Behavior , Brain Tissue Transplantation/ethics , Cell Transplantation/ethics , Central Nervous System Diseases/surgery , Clinical Trials as Topic/ethics , Cognition , Informed Consent , Biomedical Research/ethics , Brain Tissue Transplantation/adverse effects , Cell Transplantation/adverse effects , Ethics, Research , Humans , Neuropsychological Tests , Research Subjects , Surveys and Questionnaires , Therapeutic Human Experimentation/ethics
6.
Neurology ; 71(4): 288-93, 2008 Jul 22.
Article in English | MEDLINE | ID: mdl-18463365

ABSTRACT

BACKGROUND: Attempts to translate basic stem cell research into treatments for neurologic diseases and injury are well under way. With a clinical trial for one such treatment approved and in progress in the United States, and additional proposals under review, we must begin to address the ethical issues raised by such early forays into human clinical trials for cell-based interventions for neurologic conditions. METHODS: An interdisciplinary working group composed of experts in neuroscience, cell biology, bioethics, law, and transplantation, along with leading disease researchers, was convened twice over 2 years to identify and deliberate on the scientific and ethical issues raised by the transition from preclinical to clinical research of cell-based interventions for neurologic conditions. RESULTS: While the relevant ethical issues are in many respects standard challenges of human subjects research, they are heightened in complexity by the novelty of the science, the focus on the CNS, and the political climate in which the science is proceeding. CONCLUSIONS: Distinctive challenges confronting US scientists, administrators, institutional review boards, stem cell research oversight committees, and others who will need to make decisions about work involving stem cells and their derivatives and evaluate the ethics of early human trials include evaluating the risks, safety, and benefits of these trials, determining and evaluating cell line provenance, and determining inclusion criteria, informed consent, and the ethics of conducting early human trials in the public spotlight. Further study and deliberation by stakeholders is required to move toward professional and institutional policies and practices governing this research.


Subject(s)
Brain Diseases/therapy , Cell- and Tissue-Based Therapy/ethics , Clinical Trials as Topic/ethics , Neurology/ethics , Neurology/standards , Animals , Biomedical Research/ethics , Biomedical Research/standards , Biomedical Research/trends , Cell- and Tissue-Based Therapy/methods , Cell- and Tissue-Based Therapy/standards , Clinical Trials Data Monitoring Committees/standards , Clinical Trials Data Monitoring Committees/trends , Clinical Trials as Topic/standards , Ethics Committees, Research/standards , Ethics Committees, Research/trends , Humans , Neurology/trends , Risk Assessment , Stem Cell Transplantation/ethics , Stem Cell Transplantation/methods , Stem Cell Transplantation/standards , Time Factors , United States , United States Food and Drug Administration/standards , United States Food and Drug Administration/trends
7.
Phys Rev Lett ; 89(17): 172501, 2002 Oct 21.
Article in English | MEDLINE | ID: mdl-12398662

ABSTRACT

The differential cross section for electron-induced neutron knockout in the reaction 4He(e,e(')n)(3)He has been measured for the first time with a statistical accuracy of 11%. The experiment was performed in quasielastic kinematics at a momentum transfer of 300 MeV/c and in the missing-momentum range of 25-70 MeV/c. The comparison of the data with theoretical calculations shows an impressive increase of the cross section resulting from final state interaction effects. Specifically, the p-n charge-exchange process dominates the cross section in this kinematical regime.

10.
Br J Dermatol ; 142(4): 733-9, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10792224

ABSTRACT

Since the advent of psoralen-ultraviolet A (PUVA) therapy, the value of plasma 8-methoxypsoralen (8-MOP) concentrations to predict PUVA-induced erythema has been widely investigated. Plasma 8-MOP concentrations have not been proportional to, and cannot alone predict, the degree of PUVA-induced erythema. We assumed that PUVA-induced erythema was related more closely to psoralen concentrations in the skin tissue rather than those within blood vessels. This study was designed to investigate the correlations between the 8-MOP concentrations in suction blister fluid (SBF) and in plasma, with the degree of PUVA-induced erythema. 8-MOP concentrations in plasma and SBF were measured in 15 vitiligo patients and 11 volunteers. Blood and SBF samples were collected 2 h after taking 8-MOP, and 8-MOP concentrations in plasma and SBF were quantified using reverse-phase high-performance liquid chromatography. Eleven volunteers were phototested using a series of doses of ultraviolet A at the time of sampling. The erythema responses were estimated visually to determine the minimal phototoxic dose (MPD). SBF 8-MOP concentrations showed a weak positive correlation with plasma 8-MOP concentrations, which means that we could not predict the exact SBF 8-MOP concentrations using the plasma 8-MOP concentrations. The MPD showed a better correlation with the log of the SBF 8-MOP concentration than with that of the plasma 8-MOP concentration. These results show that plasma 8-MOP concentration cannot represent the exact SBF 8-MOP concentration, and that SBF 8-MOP concentrations, which are representative of the skin tissue 8-MOP level, are more closely related to the erythemal sensitivity during PUVA therapy.


Subject(s)
Erythema/etiology , PUVA Therapy/adverse effects , Adolescent , Adult , Blister/metabolism , Blister/surgery , Erythema/blood , Erythema/metabolism , Female , Humans , Male , Methoxsalen/blood , Methoxsalen/pharmacokinetics , Middle Aged , Predictive Value of Tests , Sensitivity and Specificity
11.
J Clin Microbiol ; 29(6): 1262-4, 1991 Jun.
Article in English | MEDLINE | ID: mdl-1864947

ABSTRACT

Campylobacter strains can produce a heat-labile cytotonic toxin (CTON) and various cytotoxins (CTOX). Of 22 South African Campylobacter strains tested, 86% were toxigenic (77% produced CTON, 41% produced CTOX, and 32% produced both types) and 14% were toxin negative. Campylobacter jejuni strains were 67% CTON positive and 47% CTOX positive, whereas Campylobacter coli strains were 100 and 29% positive, respectively.


Subject(s)
Bacterial Toxins/biosynthesis , Campylobacter/metabolism , Campylobacter/isolation & purification , Campylobacter jejuni/isolation & purification , Campylobacter jejuni/metabolism , Cytotoxins/biosynthesis , Humans , South Africa , Species Specificity
13.
Taehan Kanho ; 10(2): 58-9, 1971 Apr 25.
Article in Korean | MEDLINE | ID: mdl-5283337

Subject(s)
Curriculum , Nursing
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