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1.
Water Resour Res ; 51(6): 4244-4262, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26877559

RESUMO

Urbanization is found to have an impact on high flows in a urbanized catchmentThe use of point processes is advocated for trend detection and attributionThe use of process-related covariates gives a better representation of change.

2.
Indoor Air ; 24(5): 533-42, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24471934

RESUMO

Wallemia sebi has been primarily known as a spoilage fungus of dried, salted fish and other foods that are salty or sweet. However, this fungus is also very common in house dust. The health effects of chronic exposure to mold and dampness are known to be associated with both allergens and various inflammatory compounds, including the secondary metabolites of building associated fungi and their allergens. IgE sensitization to W. sebi has been long reported from housing and occupational exposures. However, its allergens have not been described previously. Strains from food have been reported to produce a number of compounds with modest toxicity. Strains from the built environment in Canada produced a number of metabolites including the known compound walleminone and a new compound 1-benzylhexahydroimidazo [1,5-α] pyridine-3,5-dione which we call wallimidione. Based on an in silico analysis, wallimidione is likely the most toxic of the metabolites reported to date from W. sebi. We found that the primary human antigen of W. sebi is a 47 kDa excreted cellulase present in high concentrations in W. sebi arthrospores. This species is a basidiomycete and, unsurprisingly, the antigen was not found in extracts of other fungi common in the built environment, all ascomycetes.


Assuntos
Antígenos/isolamento & purificação , Basidiomycota/imunologia , Celulase/imunologia , Microbiologia Ambiental , Sequência de Aminoácidos , Antígenos/química , Basidiomycota/enzimologia , Celulase/química , Celulase/isolamento & purificação , Humanos , Dados de Sequência Molecular , Metabolismo Secundário , Sesquiterpenos/isolamento & purificação
3.
Arch Toxicol ; 87(10): 1841-50, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23543010

RESUMO

People living in damp buildings are typically exposed to spore and mycelial fragments of the fungi that grow on damp building materials. There is experimental evidence that this exposure to triple-helical (1, 3)-ß-D glucan and low molecular weight toxins may be associated with non-atopic asthma observed in damp and moldy buildings. However, the mechanisms underlying this response are only partially resolved. Using the pure (1, 3)-ß-D glucan, curdlan, and the murine macrophage cell line, RAW 264.7, there were two objectives of this study. The first was to determine whether signal transduction pathways activating asthma-associated cell signaling pathways were stimulated using mouse transduction Pathway Finder(®) arrays and quantitative real-time (QRT) PCR. The second objective was to evaluate the dose and temporal responses associated with transcriptional changes in asthma-associated cytokines, the signal transduction receptor gene Dectin-1, and various transcription factor genes related to the induction of asthma using customized RT-PCR-based arrays. Compared to controls, the 10(-7) M curdlan treatment induced significant changes in gene transcription predominately in the NFkB, TGF-ß, p53, JAK/STAT, P13/AKT, phospholipase C, and stress signaling pathways. The 10(-8) M curdlan treatment mainly induced NFkB and TGF-ß pathways. Compared to controls, curdlan exposures also induced significant dose- and time-dependent changes in the gene translations. We found that that curdlan as a non-allergenic potentiator modulates a network of transduction signaling pathways not only associated with TH-1, TH-2, and TH-3 cell responses including asthma potentiation, but a variety of other cell responses in RAW 264.7 cells. These results help provide mechanistic basis for some of the phenotypic changes associated with asthma that have been observed in in vitro, in vivo, and human studies and open up a hypothesis-building process that could explain the rise of non-atopic asthma associated with fungi.


Assuntos
Asma/etiologia , Lectinas Tipo C/metabolismo , Transdução de Sinais/efeitos dos fármacos , beta-Glucanas/toxicidade , Animais , Asma/fisiopatologia , Linhagem Celular , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , NF-kappa B/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Tempo , Transcrição Gênica/efeitos dos fármacos , Fator de Crescimento Transformador beta/metabolismo , beta-Glucanas/administração & dosagem
4.
Sci Rep ; 13(1): 19775, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37957281

RESUMO

We investigate the previously observed superconductivity in ferromagnetic SmN in the context of the breakdown of order between two magnetic phases. Nitrogen vacancy doped SmN[Formula: see text] is a semiconductor which lies in the intermediary between ferromagnetic SmN and anti-ferromagnetic Sm. Optical data reported here corroborate the prediction that electrical transport is mediated by Sm 4f defect states, and electrical transport measurements characterise the metal-insulator transition over the doping range. Our measurements show that the superconducting state in nitrogen vacancy doped [Formula: see text] is the most robust near the breakdown of magnetic order, and indicate the location of a quantum critical point. Furthermore we provide additional evidence that the superconducting state is formed from majority spin electrons and thus of unconventional S = 1 type.

5.
Mar Pollut Bull ; 190: 114801, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36965265

RESUMO

Survival in the early life stages is a major factor determining the growth and stability of wildlife populations. For sea turtles, nest location must provide favorable conditions to support embryonic development. Hatching success and incubation environment of green turtle eggs were examined in July 2019 at Karan Island, a major nesting site for the species in the Arabian Gulf. Mean hatching success averaged at 38.8 % (range = 2.5-75.0 %, n = 14). Eggs that suffered early embryonic death (EED) and late embryonic death (LED) represented 19.8 % (range: 3.3-64.2 %) and 41.4 % (range: 4.8-92.6 %) of the clutch on average, respectively. Nest sand was either coarse (0.5-1 mm: mean 44.8 %, range = 30.4-56.9 % by dry weight, n = 14) or medium (0.25-0.5 mm: mean 33.6 %, range = 12.0-45.5 % by dry weight, n = 14). Mean sand moisture (4.0 %, range = 3.2-4.9 %, n = 14) was at the lower margin for successful development. Hatching success was significantly higher in clutches with sand salinity <1500 EC.uS/cm (n = 5) than those above 2500 EC.uS/cm (n = 5). Mean clutch temperatures at 1200 h increased by an average of 5.4 °C during the 50-d post-oviposition from 31.2 °C to 36.6 °C. Embryos experienced lethally high temperatures in addition to impacts of other environmental factors (salinity, moisture, sand grain size), which was related to reduced hatching success. Conservation initiatives must consider the synergistic influence of the above parameters in formulating strategies to improve the overall resilience of the green turtle population in the Arabian Gulf to anthropogenic and climate change-related stressors.


Assuntos
Tartarugas , Feminino , Animais , Areia , Comportamento de Nidação , Temperatura , Temperatura Alta
6.
Ann Surg Oncol ; 19(3): 871-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21792512

RESUMO

BACKGROUND: Unplanned excision of soft tissue sarcoma (STS) accounts for up to 40% of all initial operations for STS and is undertaken when the mass is presumed to be benign. The effect this has on outcome has never been fully established. METHODS: Patients with extremity or trunk STS between 2001 and 2005 who were treated by an initial inadvertent operation and then referred immediately to our unit were identified. Outcomes were compared with a control group of patients with STS who were stage-matched and had been treated conventionally by core biopsy and definitive surgery. Endpoints were local recurrence, distant metastases and sarcoma-specific survival. RESULTS: 134 patients who had undergone unplanned excision of STS were identified. One hundred twenty-one underwent further re-excision, and 51 (48%) of these patients had residual tumour identified after surgical re-excision. Two hundred nine stage-matched controls were identified who were treated conventionally. Median follow-up was 51.6 months. Local recurrence rates were considerably higher in the study group (23.8 vs. 11%, p = 0.0016), despite the control group having more stage 3 tumours. When the tumours were matched by stage, an increase in local recurrence was seen across all stages but was most pronounced for stage 3 tumours (37.5 vs. 14.2%, p = 0.005). Metastasis-free and sarcoma-specific survival were also significantly increased for stage 3 tumours. CONCLUSION: Unplanned initial excision of extremity soft tissue sarcoma may compromise long-term local control of extremity STS despite full further oncological management.


Assuntos
Extremidades , Recidiva Local de Neoplasia , Sarcoma/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reoperação , Sarcoma/diagnóstico , Sarcoma/mortalidade , Sarcoma/secundário , Taxa de Sobrevida , Adulto Jovem
7.
Ecol Appl ; 22(1): 184-203, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22471083

RESUMO

Research in the last several years has indicated that fire size and frequency are on the rise in western U.S. forests. Although fire size and frequency are important, they do not necessarily scale with ecosystem effects of fire, as different ecosystems have different ecological and evolutionary relationships with fire. Our study assessed trends and patterns in fire size and frequency from 1910 to 2008 (all fires > 40 ha), and the percentage of high-severity in fires from 1987 to 2008 (all fires > 400 ha) on the four national forests of northwestern California. During 1910-2008, mean and maximum fire size and total annual area burned increased, but we found no temporal trend in the percentage of high-severity fire during 1987-2008. The time series of severity data was strongly influenced by four years with region-wide lightning events that burned huge areas at primarily low-moderate severity. Regional fire rotation reached a high of 974 years in 1984 and fell to 95 years by 2008. The percentage of high-severity fire in conifer-dominated forests was generally higher in areas dominated by smaller-diameter trees than in areas with larger-diameter trees. For Douglas-fir forests, the percentage of high-severity fire did not differ significantly between areas that re-burned and areas that only burned once (10% vs. 9%) when re-burned within 30 years. Percentage of high-severity fire decreased to 5% when intervals between first and second fires were > 30 years. In contrast, in both mixed-conifer and fir/high-elevation conifer forests, the percentage of high-severity fire was less when re-burned within 30 years compared to first-time burned (12% vs. 16% for mixed conifer; 11% vs. 19% for fir/high-elevation conifer). Additionally, the percentage of high-severity fire did not differ whether the re-burn interval was less than or greater than 30 years. Years with larger fires and greatest area burned were produced by region-wide lightning events, and characterized by less winter and spring precipitation than years dominated by smaller human-ignited fires. Overall percentage of high-severity fire was generally less in years characterized by these region-wide lightning events. Our results suggest that, under certain conditions, wildfires could be more extensively used to achieve ecological and management objectives in northwestern California.


Assuntos
Ecossistema , Monitoramento Ambiental , Incêndios/estatística & dados numéricos , California , Atividades Humanas/tendências , Raio , Fatores de Tempo , Árvores
8.
Clin Infect Dis ; 52 Suppl 1: S36-43, 2011 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-21342897

RESUMO

Diagnostic tests for detecting emerging influenza virus strains with pandemic potential are critical for directing global influenza prevention and control activities. In 2008, the Centers for Disease Control and Prevention received US Food and Drug Administration approval for a highly sensitive influenza polymerase chain reaction (PCR) assay. Devices were deployed to public health laboratories in the United States and globally. Within 2 weeks of the first recognition of 2009 pandemic influenza H1N1, the Centers for Disease Control and Prevention developed and began distributing a new approved pandemic influenza H1N1 PCR assay, which used the previously deployed device platform to meet a >8-fold increase in specimen submissions. Rapid antigen tests were widely used by clinicians at the point of care; however, test sensitivity was low (40%-69%). Many clinical laboratories developed their own pandemic influenza H1N1 PCR assays to meet clinician demand. Future planning efforts should identify ways to improve availability of reliable testing to manage patient care and approaches for optimal use of molecular testing for detecting and controlling emerging influenza virus strains.


Assuntos
Controle de Doenças Transmissíveis/métodos , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/diagnóstico , Influenza Humana/epidemiologia , Pandemias/prevenção & controle , Reação em Cadeia da Polimerase/métodos , Virologia/métodos , Centers for Disease Control and Prevention, U.S. , Técnicas de Laboratório Clínico/métodos , Humanos , Influenza Humana/prevenção & controle , Influenza Humana/virologia , Estados Unidos/epidemiologia
9.
Theor Appl Genet ; 123(4): 603-13, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21573955

RESUMO

The wheat (Triticum aestivum L.) stem rust (Puccinia graminis Pers.:Pers. f.sp. tritici Eriks. and Henn.) resistance gene SrWld1 conditions resistance to all North American stem rust races and is an important gene in hard red spring (HRS) wheat cultivars. A sexually recombined race having virulence to SrWld1 was isolated in the 1980s. Our objective was to determine the genetics of resistance to the race. The recombinant race was tested with the set of stem rust differentials and with a set of 36 HRS and 6 durum cultivars. Chromosomal location studies in cultivars Len, Coteau, and Stoa were completed using aneuploid analysis, molecular markers, and allelism tests. Stem rust differential tests coded the race as TPPKC, indicating it differed from TPMKC by having added virulence on Sr30 as well as SrWld1. Genes effective against TPPKC were Sr6, Sr9a, Sr9b, Sr13, Sr24, Sr31, and Sr38. Genetic studies of resistance to TPPKC indicated that Len, Coteau, and Stoa likely carried Sr9b, that Coteau and Stoa carried Sr6, and Stoa carried Sr24. Tests of HRS and durum cultivars indicated that five HRS and one durum cultivar were susceptible to TPPKC. Susceptible HRS cultivars were postulated to have SrWld1 as their major stem rust resistance gene. Divide, the susceptible durum cultivar, was postulated to lack Sr13. We concluded that although TPPKC does not constitute a threat similar to TTKSK and its variants, some cultivars would be lost from production if TPPKC became established in the field.


Assuntos
Basidiomycota/patogenicidade , Resistência à Doença , Doenças das Plantas/genética , Triticum/genética , Aneuploidia , Basidiomycota/crescimento & desenvolvimento , Cromossomos de Plantas , Cruzamentos Genéticos , DNA de Plantas/genética , Genes de Plantas , Marcadores Genéticos , Genótipo , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Imunidade Vegetal , Triticum/imunologia , Triticum/microbiologia
10.
Langmuir ; 26(5): 3407-14, 2010 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-20025239

RESUMO

States of adsorbed dodecylamine (DDA) at a silica surface have been studied as a function of pH by vibrational spectroscopy (SFVS, FTIR), contact angle measurements, and molecular dynamics (MD) simulations. The results show that the state of adsorbed DDA at a silica surface varies significantly at different pH values. At pH 6.30, there is no pronounced adsorption of DDA cations and the surface is hydrophilic. At pH 10.0, the vibrational spectroscopy results together with contact angle measurements and MD simulations suggest that amine is adsorbed as a well organized monolayer, the hemimicelle structure. Under these conditions, dehydration occurs based on SFVS analysis and the silica surface becomes hydrophobic. In the case of pH 12.3, it has been confirmed that continued adsorption of DDA neutral molecules occurs with the amine surface state changing from a monolayer to a bilayer or a micellar surface state as revealed both from SFVS analysis and MD simulations. At this high pH, extensive surface hydration is evident from SFVS results and the silica surface becomes hydrophilic.

11.
Arch Toxicol ; 84(3): 205-20, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19904525

RESUMO

The form of (1-3)-beta-D glucan found in the cell walls of the anamorphic Trichocomaceae that grow on damp building materials is considered to have potent toxic and inflammatory effects on cells of the respiratory system. It is also considered to have a potential role in the development of non-allergenic respiratory health effects. While human studies involving experimental exposures all point to the inflammatory potential of pure curdlan, a linear (1-3)-beta-D glucan in a triple helix configuration, animal experiments result in conflicting conclusions concerning the inflammatory potency of this glucan. However, because mice appear to be a better model than guinea pigs for exploring the respiratory effects of curdlan and because molecular mechanisms associated with this glucan remain largely unknown, we conducted further work to clarify the role of curdlan on the inflammatory response using our mouse model of lung disease. This study used in situ hybridization (ISH) to probe dectin-1 mRNA transcription with a digoxigenin-labeled cDNA probe, with reverse transcription (RT)-PCR based arrays used to measure inflammation gene and receptor transcriptional responses. Also, immunohistochemistry (IHC) was used to probe dectin-1 as well as anti-mouse Ccl3, Il1-alpha, and TNF-alpha expression to evaluate dose and time-course (4 and 12 h) postexposure (PE) response patterns in the lungs of intratracheally instilled mice exposed to a single 50 mul dose of curdlan at 10(-7), 10(-8), 10(-9), and 10(-10) M/animal (=4 mug to 4 ng curdlan/kg lung wt). Dectin-1 mRNA transcription and expression was observed in bronchiolar epithelium, alveolar macrophages (AMs), and alveolar type II cells (ATIIs) of lungs exposed to 4 mug to 40 ng curdlan/kg lung wt, at both time points. Compared to controls, array analysis revealed that 54 of 83 genes assayed were significantly modulated by curdlan. mRNA transcription patterns showed both dose and time dependency, with highest transcription levels in 10(-7) and 10(-8) M treatment animals, especially at 4-h PE. Nine gene mRNA transcripts (Ccl3, Ccl11, Ccl17, Ifng, Il1alpha, Il-20, TNF-alpha, Tnfrsf1b, and CD40lg) were significantly expressed at all doses suggesting they may have a central role in immunomodulating curdlan exposures. IHC revealed Ccl3, Il1-alpha, and TNF-alpha expression in bronchiolar epithelium, AMs and ATIIs illustrate the important immunomodulatory role that these cells have in the recognition of, and response to glucan. Collectively, these results confirm the inflammatory nature of curdlan and demonstrate the complex of inflammation-associated gene responses induced by (1-3)-beta-D glucan in triple helical forms. These observations also provide a biological basis for the irritant and inflammatory response to curdlan observed in humans and animals in experimental studies.


Assuntos
Quimiocinas/genética , Pulmão/efeitos dos fármacos , Proteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética , Polissacarídeos Bacterianos/toxicidade , Transcrição Gênica/efeitos dos fármacos , beta-Glucanas/toxicidade , Animais , Quimiocinas/metabolismo , Hibridização In Situ , Intubação Intratraqueal , Lectinas Tipo C , Pulmão/metabolismo , Pulmão/patologia , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Polissacarídeos Bacterianos/administração & dosagem , RNA Mensageiro/metabolismo , Organismos Livres de Patógenos Específicos , beta-Glucanas/administração & dosagem
12.
J Cell Biol ; 128(3): 273-82, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7844142

RESUMO

The signal recognition particle receptor (SR) is required for the cotranslational targeting of both secretory and membrane proteins to the endoplasmic reticulum (ER) membrane. During targeting, the SR interacts with the signal recognition particle (SRP) which is bound to the signal sequence of the nascent protein chain. This interaction catalyzes the GTP-dependent transfer of the nascent chain from SRP to the protein translocation apparatus in the ER membrane. The SR is a heterodimeric protein comprised of a 69-kD subunit (SR alpha) and a 30-kD subunit (SR beta) which are associated with the ER membrane in an unknown manner. SR alpha and the 54-kD subunits of SRP (SRP54) each contain related GTPase domains which are required for SR and SRP function. Molecular cloning and sequencing of a cDNA encoding SR beta revealed that SR beta is a transmembrane protein and, like SR alpha and SRP54, is a member of the GTPase superfamily. Although SR beta defines its own GTPase subfamily, it is distantly related to ARF and Sar1. Using UV cross-linking, we confirm that SR beta binds GTP specifically. Proteolytic digestion experiments show that SR alpha is required for the interaction of SRP with SR. SR alpha appears to be peripherally associated with the ER membrane, and we suggest that SR beta, as an integral membrane protein, mediates the membrane association of SR alpha. The discovery of its guanine nucleotide-binding domain, however, makes it likely that its role is more complex than that of a passive anchor for SR alpha. These findings suggest that a cascade of three directly interacting GTPases functions during protein targeting to the ER membrane.


Assuntos
Retículo Endoplasmático/enzimologia , GTP Fosfo-Hidrolases/metabolismo , Membranas Intracelulares/enzimologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores de Peptídeos/metabolismo , Partícula de Reconhecimento de Sinal/metabolismo , Sequência de Aminoácidos , Animais , Clonagem Molecular , Cães , Camundongos , Dados de Sequência Molecular , Ligação Proteica , Receptores Citoplasmáticos e Nucleares/genética , Receptores de Peptídeos/genética , Homologia de Sequência de Aminoácidos
13.
Science ; 190(4209): 69-72, 1975 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-1166301

RESUMO

Four chinchillas were trained to respond differently to /t/ and /d/ consonant-vowel syllables produced by four talkers in three vowel contexts. This training generalized to novel instances, including synthetically produced /da/ and /ta/ (voice-on-set times of 0 and +80 milliseconds, respectively). In a second experiment, synthetic stimuli with voice-onset times between 0 and +80 milliseconds were presented for identification. The form of the labeling functions and the "phonetic boundaries" for chinchillas and English-speaking adults were similar.


Assuntos
Percepção Auditiva/fisiologia , Chinchila/fisiologia , Fonética , Fala , Animais , Condicionamento Psicológico , Idioma
14.
Science ; 189(4208): 1108-9, 1975 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-1162365

RESUMO

Rabbits were conditioned to avoid shock signaled by a tone. A second tone was randomly interspersed but did not signal shock. Neuronal activity 5 to 40 milliseconds after tone onset was greater to the shock-signaling tone than to the other tone. This difference reversed when the signal value of the tones was reversed.


Assuntos
Aprendizagem da Esquiva/fisiologia , Corpos Geniculados/fisiologia , Potenciais de Ação , Animais , Condicionamento Operante/fisiologia , Período de Latência Psicossexual/fisiologia , Coelhos , Reversão de Aprendizagem/fisiologia
15.
Indoor Air ; 19(6): 489-99, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19719534

RESUMO

UNLABELLED: Inuit infants have high rates of reported hospitalization for respiratory infection, associated with overcrowding and reduced ventilation. We performed a randomized, double-blind, placebo controlled trial to determine whether home heat recovery ventilators (HRV) would improve ventilation and reduce the risk of respiratory illnesses in young Inuit children. Inuit children under 6 years of age living in several communities in Nunavut, Canada were randomized to receive an active or placebo HRV. We monitored respiratory symptoms, health center encounters, and indoor air quality for 6 months. HRVs were placed in 68 homes, and 51 houses could be analyzed. Subjects had a mean age of 26.8 months. Active HRVs brought indoor carbon dioxide concentrations to within recommended concentrations. Relative humidity was also reduced. Use of HRV, compared with placebo, was associated with a progressive fall in the odds ratio for reported wheeze of 12.3% per week (95%CI 1.9-21.6%, P = 0.022). Rates of reported rhinitis were significantly lower in the HRV group than the placebo group in month 1 (odds ratio 0.20, 95%CI 0.058-0.69, P = 0.011) and in month 4 (odds ratio 0.24, 95%CI 0.054-0.90, P = 0.035). There were no significant reductions in the number of health center encounters, and there were no hospitalizations. Use of HRVs was associated with in improvement in air quality and reductions in reported respiratory symptoms in Inuit children. PRACTICAL IMPLICATIONS: Reduced ventilation is common in the houses of Inuit children in arctic Canada, and is associated with an increased risk of respiratory infection. Installation of HRV brings indoor carbon dioxide concentration, as a marker of adequate ventilation, to within recommended concentrations, although relative humidity is also reduced. Installation of HRV is associated with improvements in indoor air quality, and a reduced risk of wheezing and rhinitis not associated with cold air exposure in young Inuit children. Further research is required to explore traditional Inuit cultural attitudes about air movement in dwellings.


Assuntos
Calefação/instrumentação , Doenças Respiratórias/prevenção & controle , Ventilação , Pré-Escolar , Método Duplo-Cego , Feminino , Humanos , Lactente , Inuíte , Masculino , Nunavut
16.
Ultrason Sonochem ; 52: 446-454, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30595489

RESUMO

In this study, the effect of ultrasound (US) on the quartz-amine flotation system was investigated in detail by considering various surface chemistry techniques. The effect of ultrasound on particle size, shape factor, and surface roughness were characterized by using Brunauer-Emmett-Teller (BET) surface area measurements and scanning electron microscopy (SEM) analyses. The contact angle and bubble-particle attachment time, as well as adsorption density measurements was carried out to evaluate the effect of ultrasound on quartz surface wetting ability. In addition, atomic force microscopy (AFM) analyses were conducted, and finally micro-flotation studies were performed. As a result, it was found that the micro-flotation recovery at 2 × 10-5 M dodecyl amine hydrochloride (DAH) concentration increased from 45.45% to 63.64% with 30 W ultrasonic application at conditioning step. However, the micro-flotation recovery decreased to 37.50% when the ultrasonic power increased to 150 W. The results showed some effect of ultrasound on particle size, particle shape, and surface roughness in some extent. The increase in the contact angle and the decrease in the bubble-particle attachment time were observed. A slightly high adsorption density was measured. All these show a positive effect of ultrasound on quartz flotation with amine as a collector.

17.
Acta Physiol (Oxf) ; 225(4): e13151, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-29908102

RESUMO

AIM: To investigate the relationships between motor unit action potential amplitudes (MUAPAMP ), muscle cross-sectional area (mCSA) and composition (mEI), per cent myosin heavy chain (%MHC) areas and sex in the vastus lateralis (VL). METHODS: Ten males and 10 females performed a submaximal isometric trapezoid muscle action that included a linearly increasing, steady torque at 40% maximal voluntary contraction, and linearly decreasing segments. Surface electromyographic decomposition techniques were utilized to determine MUAPAMPS in relation to recruitment thresholds (RT). Ultrasound images were taken to quantify muscle mCSA and mEI. Muscle biopsies were collected to calculate %MHC areas. Y-intercepts and slopes were calculated for the MUAPAMP vs RT relationships for each subject. Independent-samples t tests and ANOVA models examined sex-related differences in mCSA, mEI, slopes and y-intercepts for the MUAPAMP vs RT relationships and %MHC areas. Correlations were performed among type IIA and total type II %MHC area, mCSA and the slopes and y-intercepts for the MUAPAMP vs RT relationships. RESULTS: Males exhibited greater slopes for the MUAPAMP vs RT relationships (P = .003), mCSA (P < .001) and type IIA %MHC (P = .011), whereas females had greater type I %MHC area (P = .010) and mEI (P = .024). The mCSA, type IIA and total II %MHC area variables were correlated (P < .001-.015, r = .596-.836) with the slopes from the MUAPAMP vs RT relationships. CONCLUSION: Sex-related differences in mCSA and MUAPAMPS of the higher-threshold MUs were likely the result of larger muscle fibres expressing type II characteristics for males.


Assuntos
Potenciais de Ação , Cadeias Pesadas de Miosina/isolamento & purificação , Músculo Quadríceps/fisiologia , Recrutamento Neurofisiológico , Caracteres Sexuais , Feminino , Humanos , Masculino , Músculo Quadríceps/anatomia & histologia , Adulto Jovem
18.
Neuron ; 11(3): 449-58, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8398139

RESUMO

We report the cloning and characterization of a novel serotonin receptor, designated as 5-HT7, which is coupled to the stimulation of adenylyl cyclase. 5-HT7 mRNA is expressed discretely throughout the CNS, predominantly in the thalamus and hypothalamus. 5-HT7 has a unique pharmacological profile that redefines agonist and antagonist classification of ligands previously thought to be "selective." The circadian phase of spontaneous neuronal activity of the rat suprachiasmatic nucleus of the hypothalamus advances in response to serotonin ligands with a pharmacological profile consistent exclusively with that of 5-HT7. These findings suggest a physiological role in the regulation of circadian rhythms for one subtype of serotonin receptor, 5-HT7, and provide a pharmacological test to evaluate its role in other neuronal systems.


Assuntos
Adenilil Ciclases/metabolismo , Ritmo Circadiano/fisiologia , Receptores de Serotonina/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Diencéfalo/metabolismo , Ativação Enzimática , Proteínas de Ligação ao GTP/metabolismo , Sondas Moleculares/genética , Dados de Sequência Molecular , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Serotonina/genética , Antagonistas da Serotonina/metabolismo , Agonistas do Receptor de Serotonina/metabolismo
19.
Adv Exp Med Biol ; 619: 139-52, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18461768

RESUMO

Nebraska agencies and public health organizations collaboratively addressed cyanobacterial issues for the first time after two dogs died within hours of drinking water from a small private lake south of Omaha on May 4, 2004. A necropsy on one of the dogs revealed that the cause of death was due to ingestion of Microcystin toxins. Within two weeks after the dog deaths, state and local officials jointly developed strategies for monitoring cyanobacterial blooms and issuing public health alerts and advisories. Weekly sampling of public lakes for microcystin toxins and cyanobacteria was initiated during the week of May 17, 2004. ELISA laboratory equipment and supplies were purchased to achieve a quick turnaround time for measuring weekly lake samples for total microcystins so that public health advisories and alerts could be issued prior to each weekend's recreational activities. A conservative approach was selected to protect human health, pets, and livestock, which included collecting worst-case samples from cyanobacterial blooms; freezing and thawing of samples to lyse algal cells and release toxins prior to laboratory analysis; and using action levels of 15 ppb and 2 ppb of total microcystins, respectively, for issuing health alerts and health advisories. During 2004, five dog deaths, numerous wildlife and livestock deaths, and more than 50 accounts of human skin rashes, lesions, or gastrointestinal illnesses were reported at Nebraska lakes. Health alerts were issued for 26 lakes and health advisories for 69 lakes. Four lakes were on health alert for 12 or more weeks. The primary cyanobacterial bloom-forming genera identified in Nebraska lakes were Anabaena, Aphanizomenon, and Microcystis. Preliminary assessments of lake water quality data indicated that lower lake levels from the recent drought and low nitrogen to phosphorus ratios may have contributed, in part, to the increased numbers of cyanobacterial complaints and problems that occurred in 2004.


Assuntos
Cianobactérias/patogenicidade , Eutrofização , Água Doce/microbiologia , Animais , Toxinas Bacterianas/análise , Toxinas Bacterianas/toxicidade , Cianobactérias/isolamento & purificação , Toxinas de Cianobactérias , Humanos , Toxinas Marinhas/análise , Toxinas Marinhas/toxicidade , Meios de Comunicação de Massa , Microcistinas/análise , Microcistinas/toxicidade , Microcystis/isolamento & purificação , Microcystis/patogenicidade , Nebraska , Saúde Pública
20.
Case Rep Orthop ; 2018: 9042820, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30652040

RESUMO

Case. Compartment syndrome following muscle rupture is a rare entity with few mentions in the literature. We present a case of pectoralis major rupture in a 38-year-old male that evolved into compartment syndrome of the anterior compartment of the arm. Rupture of the pectoralis is uncommon and most often occurs during weight lifting. Compartment syndrome secondary to this injury is extremely uncommon, with only one reported case in the pectoralis major itself and several cases of biceps compartment syndrome. Due to the potentially devastating consequences of a missed compartment syndrome, it is imperative that physicians maintain a high level of suspicion in patients with these unusual injuries presenting with severe swelling and pain.

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