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1.
Environ Technol ; 40(6): 701-715, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29125054

RESUMO

The drive to a more circular economy has created increasing interest in recycling organic wastes as bio-based fertilizers. This study screened 15 different manures, digestates, sludges, composts, industry by-products, and struvites. Nitrogen (N) and phosphorous (P) release was compared following addition to soil. Three waste materials were then 'upgraded' using heating and pressure (105°C at 220 kPa), alkalinization (pH 10), or sonification to modify N and P release properties, and compared in a second soil incubation. Generally, maximum N release was negatively correlated with the CN ratio of the material (r = -0.6). Composted, dried, or raw organic waste materials released less N (mean of 10.8 ± 0.5%, 45.3 ± 7.2%, and 47.4 ± 3.2% of total N added respectively) than digestates, industry-derived organic fertilizer products, and struvites (mean of 58.2 ± 2.8%, 77.7 ± 6.0%, and 100.0 ± 13.1% of total N added respectively). No analyzed chemical property or processing type could explain differences in P release. No single upgrading treatment consistently increased N or P release. However, for one raw biosolid, heating at a low temperature (105°C) with pressure did increase N release as a percentage of total N added to soil from 30% to 43%.


Assuntos
Fertilizantes , Nitrogênio , Esterco , Fósforo , Solo
2.
Lupus ; 27(3): 494-500, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29251171

RESUMO

Objective Few descriptions of physical disability in childhood-onset SLE (cSLE) exist. We sought to describe disability in a large North American cohort of patients with cSLE and identify predictors of disability. Methods Sociodemographic and clinical data were obtained from the Childhood Arthritis and Rheumatology Research Alliance (CARRA) Legacy Registry for patients with cSLE enrolled between May 2010 and October 2014. The Childhood Health Assessment Questionnaire (CHAQ) was used to assess disability and physical functioning. Chi-square tests were used for univariate analyses, and multivariate logistic regression was used to assess predictors of disability. Results We analyzed data for 939 patients with cSLE. The median and mean CHAQ scores were 0 and 0.25, respectively, and 41% of the cohort had at least mild disability. Arthritis and higher pain scores were significantly associated with disability as compared to those without disability ( p < 0.001). In multivariate logistic regression analysis, low annual income, arthritis, and higher pain scores were associated with disability at baseline. Conclusions Disability as measured by baseline CHAQ was fairly common in cSLE patients in the CARRA Legacy Registry, and was associated with low household income, arthritis, and higher pain scores. In addition to optimal disease control, ensuring psychosocial supports and addressing pain may reduce disability in cSLE. Further study is needed of disability in cSLE.


Assuntos
Avaliação da Deficiência , Lúpus Eritematoso Sistêmico/fisiopatologia , Medição da Dor , Adolescente , Idade de Início , Canadá , Distribuição de Qui-Quadrado , Criança , Estudos de Coortes , Feminino , Humanos , Modelos Logísticos , Masculino , Análise Multivariada , Qualidade de Vida , Sistema de Registros , Índice de Gravidade de Doença , Sociedades Médicas , Estados Unidos
3.
J Environ Manage ; 168: 236-44, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26716355

RESUMO

The combined effects of pig slurry acidification, subsequent separation techniques and biochar production from the solid fraction on N mineralisation and N2O and CO2 emissions in soil were investigated in an incubation experiment. Acidification of pig slurry increased N availability from the separated solid fractions in soil, but did not affect N2O and CO2 emissions. However acidification reduced soil N and C turnover from the liquid fraction. The use of more advanced separation techniques (flocculation and drainage > decanting centrifuge > screw press) increased N mineralisation from acidified solid fractions, but also increased N2O and CO2 emissions in soil amended with the liquid fraction. Finally, the biochar production from the solid fraction of pig slurry resulted in a very recalcitrant material, which reduced N and C mineralisation in soil compared to the raw solid fractions.


Assuntos
Carbono/química , Carvão Vegetal/química , Gases/química , Nitrogênio/química , Poluentes do Solo/química , Solo/química , Ácidos/química , Animais , Suínos
4.
J Hum Nutr Diet ; 27(6): 542-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25580488

RESUMO

BACKGROUND: Currently , the only treatment for coeliac disease is life long adherence to a strict gluten-free diet. Strict adherence to a gluten-free diet is challenging, with recent reports suggesting that adherence rates range from 42% to 91%. The present study aimed to: (i) identify motives for adhering to a gluten-free diet and (ii) explore factors implicated in adherence and non-adherence behaviour in terms of accidental and purposeful gluten consumption among adults with coeliac disease. METHODS: Two hundred and three adults with coeliac disease completed an online questionnaire. Using a qualitative design, relationships were examined between reported adherence and motivation to follow a gluten-free diet, as well as the onset, duration and severity of symptoms. RESULTS: Feelings of desperation ('hitting rock bottom') and needing to gain or lose weight were associated with the strictest adherence to a gluten-free diet. Participants who accidentally consumed gluten over the past week developed symptoms the most quickly and reported the most pain over the past 6 months. Participants who consumed gluten on purpose over the past week reported a shorter duration of symptoms and less pain over the past 6 months. CONCLUSIONS: Hitting rock bottom and needing to gain or lose weight were factors associated with the strictest adherence, when considered in the context of both accidental and purposeful gluten consumption. Future research is warranted to develop resources to help people with coeliac disease follow a strict gluten-free diet.


Assuntos
Doença Celíaca/dietoterapia , Dieta Livre de Glúten , Glutens/administração & dosagem , Motivação , Cooperação do Paciente/psicologia , Adulto , Peso Corporal , Doença Celíaca/complicações , Doença Celíaca/psicologia , Emoções , Humanos , Pessoa de Meia-Idade , Dor/etiologia , Dor/psicologia , Pesquisa Qualitativa , Inquéritos e Questionários
5.
Nanotechnology ; 24(15): 155704, 2013 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-23518871

RESUMO

Carbon nanotubes (CNTs) were grown on the surface of carbon fibers utilizing a relatively low temperature synthesis technique; graphitic structures by design (GSD). To probe the effects of the synthesis protocols on the mechanical properties, other samples with surface grown CNTs were prepared using catalytic chemical vapor deposition (CCVD). The woven graphite fabrics were thermally shielded with a thin film of SiO2 and CNTs were grown on top of this film. Raman spectroscopy and electron microscopy revealed the grown species to be multi-walled carbon nanotubes (MWCNTs). The damping performance of the hybrid CNT-carbon fiber-reinforced epoxy composite was examined using dynamic mechanical analysis (DMA). Mechanical testing confirmed that the degradations in the strength and stiffness as a result of the GSD process are far less than those encountered through using the CCVD technique and yet are negligible compared to the reference samples. The DMA results indicated that, despite the minimal degradation in the storage modulus, the loss tangent (damping) for the hybrid composites utilizing GSD-grown MWCNTs improved by 56% compared to the reference samples (based on raw carbon fibers with no surface treatment or surface grown carbon nanotubes) over the frequency range 1-60 Hz. These results indicated that the energy dissipation in the GSD-grown MWCNTs composite can be primarily attributed to the frictional sliding at the nanotube/epoxy interface and to a lesser extent to the stiff thermal shielding SiO2 film on the fiber/matrix interface.

7.
Phys Rev E Stat Nonlin Soft Matter Phys ; 83(5 Pt 1): 051108, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21728491

RESUMO

Population dynamics in systems composed of cyclically competing species has been of increasing interest recently. Here we investigate a system with four or more species. Using mean field theory, we study in detail the trajectories in configuration space of the population fractions. We discover a variety of orbits, shaped like saddles, spirals, and straight lines. Many of their properties are found explicitly. Most remarkably, we identify a collective variable that evolves simply as an exponential: Q ∝ e(λt), where λ is a function of the reaction rates. It provides information on the state of the system for late times (as well as for t→-∞). We discuss implications of these results for the evolution of a finite, stochastic system. A generalization to an arbitrary number of cyclically competing species yields valuable insights into universal properties of such systems.


Assuntos
Modelos Teóricos , Dinâmica Populacional , Evolução Biológica , Extinção Biológica , Processos Estocásticos
8.
Clin Exp Allergy ; 40(9): 1406-13, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20345998

RESUMO

BACKGROUND: Infection with Mycoplasma pneumoniae (Mp) in asthma can occur both acutely and chronically with an associated Th2 inflammatory response and/or increased numbers of bronchial mast cells. Mast cells have previously been shown to promote mycoplasma clearance in mice; however, it is unknown whether mast cells would aid Mp clearance under allergic conditions. OBJECTIVE: Our aim was to determine the impact of allergic inflammation on mast cell-mediated lung Mp clearance. Furthermore, as we have previously demonstrated an essential role for IL-6 in lung Mp clearance we also investigated the role of mast cell-derived IL-6. METHODS: Mast cell-deficient (WBB6F1/J-Kit(W)/Kit(W-v)) mice were challenged with ovalbumin to induce airway inflammation before Mp infection. The role of mast cell-derived IL-6 in bacterial clearance was further investigated by reconstitution of mast cell-deficient mice with IL-6(-/-) mast cells. RESULTS: Allergic mast cell-deficient mice exhibited increased lung Mp burden compared with control littermates. Intravenous adoptive transfer of wild-type and IL-6(-/-) mast cells significantly improved Mp clearance in mast cell-deficient mice. Acutely after Mp infection, allergen-challenged mast cell-deficient mice had increased levels of the pro-inflammatory cytokines IL-6 and TNF-alpha in the bronchoalveolar lavage (BAL) fluid. The total number of neutrophils was also increased in mast cell-deficient mice. CONCLUSIONS: Our results establish that mast cells aid host defense against Mp in an allergic setting and that while IL-6 is necessary for lung Mp clearance, mast cell-derived IL-6 is not required.


Assuntos
Asma/complicações , Interações Hospedeiro-Patógeno/imunologia , Hipersensibilidade/microbiologia , Imunidade Inata , Pulmão/imunologia , Mastócitos/imunologia , Mycoplasma pneumoniae , Pneumonia por Mycoplasma/imunologia , Animais , Hipersensibilidade/imunologia , Interleucina-6/imunologia , Pulmão/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pneumonia por Mycoplasma/complicações
9.
Dent Assist ; 75(3): 12, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16808191
10.
J Hum Nutr Diet ; 19(1): 41-9, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16448474

RESUMO

UNLABELLED: OBJECTIVE We sought to evaluate the impact of the gluten-free diet on the 5,240 members of the Canadian Celiac Association (CCA). Data are presented on 2,681 adults (>or=16 years) with biopsy-proven celiac disease (CD). METHODS: A mail-out survey was used. Quality of life was evaluated using the 'SF12', and celiac-specific questions. RESULTS: Mean age was 56 years, mean age at diagnosis was 45 years, and 75% were female. The 'SF12' summary scores were similar to normative Canadian data, but were significantly lower for females and newly diagnosed patients. Respondents reported: following a gluten-free (GF) diet (90%), improvement on the diet (83%), and difficulties following the diet (44%), which included: determining if foods were GF (85%), finding GF foods in stores (83%), avoiding restaurants (79%), and avoiding travel (38%). Most common reactions to consumed gluten (among 73%) included pain, diarrhea, bloating, fatigue, nausea, and headache. Excellent information on CD and its treatment was provided by the CCA (64%), gastroenterologists (28%), dietitians (26%) and family doctor (12%). CONCLUSIONS: Quality of life in those with CD could be increased with early diagnosis, increased availability of gluten-free foods, improved food labelling, and better dietary instruction. Education of physicians and dietitians about CD and its treatment is essential.


Assuntos
Doença Celíaca/dietoterapia , Doença Celíaca/psicologia , Glutens/administração & dosagem , Qualidade de Vida , Canadá , Doença Celíaca/diagnóstico , Feminino , Rotulagem de Alimentos/normas , Glutens/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Educação de Pacientes como Assunto , Resultado do Tratamento
11.
Mol Ther ; 4(6): 614-21, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11735346

RESUMO

We previously reported the efficiency of gene transfer in fetal monkeys using retroviral vectors and an intraperitoneal (IP) approach. Here, we explored intrapulmonary administration to determine whether gene transfer can be limited to the developing lung. The HIV-1-derived lentiviral vector (VSV-G pseudotyped; 1 x 10(7) infectious particles/fetus), using the enhanced green fluorescent protein (EGFP) as a reporter, was directly injected into fetal lung with ultrasound guidance (n=4; 55 or 70 days gestation; term 165+/-10 days). Fetuses were monitored sonographically, fetal/maternal blood samples collected during gestation, and four of four healthy newborns were delivered at term. All lung lobes were positive for the transgene (< or = 1%) when assessed by PCR, and transgene expression was observed by direct fluorescence microscopy and flow cytometry. The results of this study show the following: (1) successful gene transfer in fetal monkeys using an intrapulmonary approach; (2) less transduction of non-pulmonary tissues with gene transfer at 70 days gestation compared with 55 days gestation or use of an IP approach; (3) that the pulmonary epithelium was EGFP-positive by immunohistochemistry; and (4) no evidence of transplacental transport of vector sequences or antibody responses in the dams. The results of these investigations indicate the efficiency of fetal gene transfer by intrapulmonary delivery, and emphasize the importance of the fetal monkey as a preclinical model system for exploring in utero genetic treatment strategies for pulmonary disorders.


Assuntos
HIV-1/genética , Pulmão/embriologia , Pulmão/metabolismo , Macaca mulatta/embriologia , Animais , Primers do DNA/química , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Técnicas de Transferência de Genes , Terapia Genética/métodos , Vetores Genéticos , Proteínas de Fluorescência Verde , Células-Tronco Hematopoéticas/fisiologia , Humanos , Técnicas Imunoenzimáticas , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Macaca mulatta/genética , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas
16.
Mol Ther ; 3(2): 128-38, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11237669

RESUMO

Many life-threatening conditions that can be diagnosed early in gestation may be treatable in utero using gene therapy. In order to determine in utero gene transfer efficiency and safety, studies were conducted with fetal rhesus monkeys as a model for the human. Included in these studies were Moloney murine leukemia virus (MLV)-based amphotropic retrovirus, vesicular stomatitis virus-G (VSV-G) pseudotyped MLV, and a VSV-G pseudotyped HIV-1-based vector, all expressing the enhanced green fluorescent protein (EGFP) as a reporter gene and driven by a cytomegalovirus-immediate early promoter (N = 16). Rhesus monkey fetuses were administered viral vector supernatant preparations by the intraperitoneal (ip) (N = 14) or intrahepatic (ih) (N = 2) routes via ultrasound guidance at 55 +/- 5 days gestation (late first trimester; term 165 +/- 10 days). Fetuses were monitored sonographically, specimens were collected prenatally and postnatally, and tissue harvests were performed at birth or 3 or 6 months postnatal age (3-10 months post-gene transfer). PCR analyses demonstrated that transduced cells were present at approximately 1.2% in peripheral blood mononuclear cells from fetuses administered amphotropic MLV, <0.5% in fetuses receiving MLV/VSV-G, and approximately 4.2% for the lentiviral vector, which decreased to 2% at birth. Hematopoietic progenitors showed that overall (mean of all time points assessed), approximately 25% of the collected colonies were positive for the EGFP transgene with the lentiviral vector, which was significantly greater than results achieved with the MLV-based vector systems (4-9%; P < or = 0.001-0.016). At necropsy, 0.001-10% of the total genomic DNA was positive for EGFP in most tissues for all groups. EGFP-positive fluorescent cells were found in cell suspensions of thymus, liver, spleen, lymph nodes, cerebral cortex, and bone marrow (0.5-6%). Overall, the results of these studies have shown: (1) healthy infants expressing vector sequences up to 10 months post-gene transfer, (2) fetal primate administration of retroviral vectors results in gene transfer to multiple organ systems, (3) the highest level of gene transfer to hematopoietic progenitors was observed with the lentiviral vector system, and (4) there was no evidence of transplacental transfer of vector sequences into the dams. The rhesus monkey is an important preclinical primate model system for exploring gene transfer approaches for future applications in humans.


Assuntos
Técnicas de Transferência de Genes , Terapia Genética/métodos , Vetores Genéticos , Macaca mulatta/genética , Glicoproteínas de Membrana , Retroviridae/genética , Animais , Azacitidina/farmacologia , Citomegalovirus/genética , Relação Dose-Resposta a Droga , Feminino , Citometria de Fluxo , Genes Reporter , Proteínas de Fluorescência Verde , HIV-1/genética , Humanos , Lentivirus/genética , Leucócitos Mononucleares/metabolismo , Proteínas Luminescentes/genética , Macaca mulatta/embriologia , Masculino , Modelos Genéticos , Vírus da Leucemia Murina de Moloney/genética , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Distribuição Tecidual , Proteínas do Envelope Viral/genética
17.
Phys Rev Lett ; 84(18): 4043-6, 2000 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-10990606

RESUMO

The E815 (NuTeV) neutrino experiment has performed a search for a 33. 9 MeV/c(2) weakly interacting neutral particle produced in pion decay. Such a particle may be responsible for an anomaly in the timing distribution of neutrino interactions in the KARMEN experiment. E815 has searched for this particle's decays in an instrumented decay region; no evidence for this particle was found. The search is sensitive to pion branching ratios as low as 10(-13).

18.
J Womens Health Gend Based Med ; 9(6): 617-23, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10957750

RESUMO

Gender bias, described among practicing physicians, has rarely been examined in medical students. The current study examined the influence of gender bias on medical students' clinical decision making. We experimentally manipulated patient gender in 27 written clinical vignettes embedded in the United States Medical Licensing Examination (USMLE) Step 2 examination (a multiple-choice test of clinical decision making). Female and male patient versions of selected test cases were created within three categories: (1) diseases with previously established evidence of gender bias in the diagnosis or management of the disease, (2) diseases with a higher prevalence in a specific gender, and (3) diseases with similar prevalence in both genders and without evidence of gender bias in the literature. Among the 3059 students who wrote the USMLE Step 2 examination in August 1998, there were small but significant differences in performance on the 12 gender bias cases. Students performed worse for the female patient version of the cases compared with the male patient version of the cases (mean of 55.8% correct for female cases compared with 57.7% correct for male cases) (p < 0. 01). Our data suggest that students were variably influenced by gender bias in their investigation and management of patients in a written test of clinical decision making.


Assuntos
Tomada de Decisões , Identidade de Gênero , Planejamento de Assistência ao Paciente , Preconceito , Saúde da Mulher , Adulto , Medicina Clínica , Educação Médica , Feminino , Humanos , Masculino
19.
Mol Ther ; 2(1): 71-80, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10899830

RESUMO

Lentiviral vectors have been proposed as a more efficient alternative to Moloney murine leukemia virus-based retroviral vectors for transduction of human hematopoietic progenitors and stem cells. These studies were designed to evaluate the conditions that influence transduction frequency of CD34(+) progenitors, with the goal of optimizing efficiency of stable gene transfer with lentiviral vectors. CD34(+) human cord blood cells and 293 cells were transduced with a human immunodeficiency virus (HIV)-1 derived lentiviral vector pseudotyped with vesicular stomatitis virus glycoprotein and carrying an internal human cytomegalovirus promoter driving enhanced green fluorescent protein (eGFP) expression. Using fluorescence-activated cell sorting analysis of eGFP, we observed pseudotransduction beginning at the time of vector addition and lasting up to 24 h in CD34(+) cells and up to 72 h in 293 cells. Integrase-defective lentiviral vector caused transient eGFP expression for up to 10 days in CD34(+) cells and for up to 14 days in 293 cells. Protamine sulfate conferred no increase in transduction efficiency of CD34(+) cells on fibronectin-coated plates. Transduction frequency was related directly to vector concentration and not to multiplicity of infection across the ranges tested. First- and second-generation lentiviral vectors transduced CD34(+) cells equally, demonstrating a lack of dependence on HIV-1 accessory proteins. These findings will be useful for the optimal utilization of this new class of vectors for transduction of human hematopoietic stem cells.


Assuntos
Antígenos CD34/genética , Vetores Genéticos , Células-Tronco Hematopoéticas/metabolismo , Lentivirus/genética , Glicoproteínas de Membrana , Transdução Genética , Linhagem Celular , Separação Celular , Citomegalovirus/genética , Sangue Fetal/citologia , Fibronectinas/metabolismo , Citometria de Fluxo , Técnicas de Transferência de Genes , Proteínas de Fluorescência Verde , HIV-1/genética , Antagonistas de Heparina/farmacologia , Humanos , Proteínas Luminescentes/metabolismo , Plasmídeos/metabolismo , Regiões Promotoras Genéticas , Protaminas/farmacologia , Fatores de Tempo , Transfecção , Proteínas do Envelope Viral/genética
20.
Acad Med ; 75(5): 426-31, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10824764

RESUMO

In 1998, the authors, acting on behalf of the National Board of Medical Examiners (NBME), undertook a review of the scoring policy for the United States Medical Licensing Examination (USMLE). The main goal was to determine the likely effect of changing from numeric score reporting to reporting pass-fail status. Several groups were surveyed across the nation to learn how they felt they would be affected by such a change, and why: all 54 medical boards; 1,600 randomly selected examinees (including 250 foreign medical graduates) who had recently taken either Step 1, Step 2, or Step 3 of the USMLE; 2,000 residency directors; the deans, education deans, and student affairs deans at all 125 U.S. medical schools accredited by the Liaison Committee on Medical Education; and all 17 members of the Council of Medical Specialty Societies. Responses from the different groups surveyed varied from 80% to a little less than half. The authors describe in detail the various views of the respondents and their reasons. Some members in each group favored each of the reporting formats, but the trend was to favor numeric score reporting. The majority of the responding examinees desired that their USMLE scores be sent to them in numeric form but sent to their schools and to residency directors in pass-fail form. Based on the responses and a thorough discussion of their implications, the Composite Committee (which determines USMLE score-reporting policy) decided that there is no basis at this time for changing the current policy, but that it would review the policy in the future when necessary.


Assuntos
Competência Clínica/estatística & dados numéricos , Avaliação Educacional , Licenciamento , Coleta de Dados , Estados Unidos
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