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1.
Sci Data ; 9(1): 439, 2022 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-35871220

RESUMO

Over a five-month time window between March and July 2020, scientists deployed two small uncrewed aircraft systems (sUAS) to the central Arctic Ocean as part of legs three and four of the MOSAiC expedition. These sUAS were flown to measure the thermodynamic and kinematic state of the lower atmosphere, including collecting information on temperature, pressure, humidity and winds between the surface and 1 km, as well as to document ice properties, including albedo, melt pond fraction, and open water amounts. The atmospheric state flights were primarily conducted by the DataHawk2 sUAS, which was operated primarily in a profiling manner, while the surface property flights were conducted using the HELiX sUAS, which flew grid patterns, profiles, and hover flights. In total, over 120 flights were conducted and over 48 flight hours of data were collected, sampling conditions that included temperatures as low as -35 °C and as warm as 15 °C, spanning the summer melt season.

2.
Sci Total Environ ; 820: 153224, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35063520

RESUMO

Treated effluent from municipal wastewater treatment plants (WWTPs) is a major source of contamination that can impact population size, community structure, and biodiversity of aquatic organisms. However, because the majority of field research occurs during warmer periods of the year, the impacts of wastewater effluent on aquatic communities during winter has largely been neglected. In this study, we assessed the impacts of wastewater effluent on aquatic benthic macroinvertebrate (benthos) communities along the effluent gradients of two WWTPs discharging into Hamilton Harbour, Canada, during summer and winter using artificial substrates incubated for 8 weeks. At the larger of the two plants, benthic macroinvertebrate abundance was higher and diversity was lower at sites downstream of the outfall compared to upstream sites in both seasons. Whereas at the smaller plant, the opposite was observed, abundance increased and diversity decreased with distance from the outfall in both seasons. While the impacts of wastewater on benthic communities were largely similar between seasons, we did detect several general seasonal trends - family diversity of macroinvertebrates was lower during winter at both WWTPs and total abundance was also lower during winter, but only significantly so at the smaller WWTP. Further, benthic macroinvertebrate community composition differed significantly along the effluent gradients, with sites closest and farthest from the outfall being the most dissimilar. Our contrasting results between the WWTPs demonstrate that plants, with different treatment capabilities and effluent-receiving environments (industrial/urban versus wetland), can dictate how wastewater effluent impacts benthic macroinvertebrate communities.


Assuntos
Purificação da Água , Organismos Aquáticos , Biodiversidade , Monitoramento Ambiental , Estações do Ano , Águas Residuárias/análise
3.
Dalton Trans ; 43(41): 15419-28, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25188908

RESUMO

A set of ß-ketoimidazolium and ß-ketoimidazolinium salts of the general formula [R(1)C(O)CH2{CH[NCR(3)CR(3)N(R(2))]}]X (R(1) = (t)Bu, naphth; R(2) = (i)Pr, Mes, (t)Bu; R(3) = H, Me, (H)2; X = Cl, Br) show contrasting reactivity with superhydride bases MHBEt3; two are reduced to chiral ß-alcohol carbene-boranes R(1)CH(OH)CH2{C(BEt3)[NCR(3)CR(3)N(R(2))]} 2 (R(1) = (t)Bu; R(2) = (i)Pr, Mes; R(3) = H), two with bulky R(2) substituents are reduced to chiral ß-borate imidazolium salts [R(1)CH(OBEt3)CH2{CH[NCR(3)CR(3)N(R(2))]}]X 3 (R(1) = (t)Bu, naphth; R(2) = Mes, (t)Bu; R(3) = H, Me; X = Cl, Br), and the two saturated heterocycle derivatives remain unreduced but form carbene-borane adducts R(1)C(O)CH2{C(BEt3)[NCR(3)CR(3)N(R(2))]} 4 (R(1) = (t)Bu, naphth; R(2) = Mes; R(3) = (H)2). Heating solutions of the imidazolium borates 3 results in the elimination of ethane, in the first example of organic borates functioning as Brønsted bases and forming carbene boranes R(1)CH(OBEt2)CH2{C[NCR(3)CR(3)N(R(2))]} 5 (R(1) = naphth; R(2) = Mes; R(3) = Me). The 'abnormal' carbene borane of the form 2 R(1)CH(OH)CH2{CH[NC(BEt3)CR(3)N(R(2))]} (R(1) = (t)Bu; R(2) = (t)Bu; R(3) = H), is also accessible by thermolysis of 3, suggesting that the carbene-borane alcohol is a more thermodynamically stable combination than the zwitterionic imidazolium borate. High-temperature thermolysis also can result in complete cleavage of the alcohol arm, eliminating tert-butyloxirane and forming the B-N bound imidazolium borate 7. The strong dependence of reaction products on the steric and electronic properties of each imidazole precursor molecule is discussed.

4.
Appetite ; 71: 158-62, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23962401

RESUMO

Elaborated Intrusion (EI) Theory proposes that cravings occur when involuntary thoughts about food are elaborated; a key part of elaboration is affectively-charged imagery. Craving can be weakened by working memory tasks that block imagery. EI Theory predicts that cravings should also be reduced by preventing involuntary thoughts being elaborated in the first place. Research has found that imagery techniques such as body scanning and guided imagery can reduce the occurrence of food thoughts. This study tested the prediction that these techniques also reduce craving. We asked participants to abstain from food overnight, and then to carry out 10 min of body scanning, guided imagery, or a control mind wandering task. They rated their craving at 10 points during the task on a single item measure, and before and after the task using the Craving Experience Questionnaire. While craving rose during the task for the mind wandering group, neither the guided imagery nor body scanning group showed an increase. These effects were not detected by the CEQ, suggesting that they are only present during the competing task. As they require no devices or materials and are unobtrusive, brief guided imagery strategies might form useful components of weight loss programmes that attempt to address cravings.


Assuntos
Atenção/fisiologia , Imagem Corporal/psicologia , Dieta/psicologia , Imagens, Psicoterapia/métodos , Adolescente , Adulto , Feminino , Seguimentos , Humanos , Masculino , Memória de Curto Prazo/fisiologia , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
5.
South Med J ; 103(6): 505-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20710131

RESUMO

BACKGROUND: Chronic pancreatitis is commonly associated with debilitating abdominal pain, in part due to pancreatic duct obstruction. Pancreatic stones are often impossible to extract from the duct with endoscopic retrograde cholangiopancreatography alone. Extracorporeal shock wave lithotripsy (ESWL) is commonly used for fragmentation of obstructing nephrolithiasis and has demonstrated effectiveness in management of pancreatic stones. Our aim was to examine the outcomes of the first 30 patients with symptomatic pancreatic stones treated with a combination of ESWL and endoscopic therapies. METHODS: Patients with symptomatic chronic calcific pancreatitis referred for ESWL (2005-2009) were included. Technical success of ESWL was defined as a) stone fragmentation sufficient to allow extraction of main duct stones at ERCP or b) absence of the targeted main pancreatic duct stones on follow-up radiography. Clinical success of ESWL was defined by Patient Global Impression of Improvement (PGII) score of at least slightly improved. RESULTS: Thirty patients underwent ESWL. One patient was excluded due to adenocarcinoma. Technical success was achieved in 17/29 (58.6%) patients. 25 (86.2%) patients were available for follow-up (median 35 months, range 3-52 months). Fifteen of twenty-five (60%) patients experienced clinical improvement (10 patients very much improved), but there was no significant reduction in the proportion taking narcotics (50% before vs. 44.4% after ESWL). Pancreatic surgery has been avoided to date in 16 (64%) of the 25 patients. CONCLUSIONS: A multidisciplinary approach, combining ERCP and ESWL, to painful obstructing pancreatic duct stones provided symptomatic improvement and allowed pancreatic surgery to be avoided in the majority of patients.


Assuntos
Calcinose/terapia , Colangiopancreatografia Retrógrada Endoscópica , Cálculos Biliares/terapia , Litotripsia , Ductos Pancreáticos , Pancreatite Crônica/terapia , Adulto , Idoso , Analgésicos Opioides/uso terapêutico , Terapia Combinada , Uso de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor/tratamento farmacológico , Dor/etiologia , Equipe de Assistência ao Paciente , Estudos Retrospectivos , Resultado do Tratamento
6.
Eur J Pharmacol ; 530(1-2): 95-102, 2006 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-16364288

RESUMO

Glycyl-glutamine (Gly-Gln) is an inhibitory dipeptide synthesized from beta-endorphin(1-31). Previously, we showed that Gly-Gln inhibits morphine conditioned place preference, tolerance, dependence and withdrawal. In this study, we tested whether Gly-Gln's inhibitory activity extends to other rewarding drugs, specifically nicotine. Rats were conditioned with nicotine (0.6 mg/kg, s.c.) for four days and tested on day five. Glycyl-glutamine (100 nmol i.c.v.) inhibited acquisition and expression of a nicotine place preference significantly. Cyclo(Gly-Gln) (100 nmol i.c.v. or 25 mg/kg i.p.), a cyclic Gly-Gln derivative, blocked expression of nicotine place preference but Gly-d-Gln (100 nmol i.c.v.) was ineffective. To study nicotine withdrawal, rats were treated with nicotine (9 mg/kg/day) for seven days and conditioned place aversion was induced with mecamylamine (1 mg/kg, s.c.). Glycyl-glutamine blocked acquisition of place aversion to mecamylamine but not U50,488, a kappa opioid receptor agonist. Glycyl-glutamine thus inhibits the rewarding effects of nicotine and attenuates withdrawal in nicotine dependent rats.


Assuntos
Condicionamento Psicológico/efeitos dos fármacos , Dipeptídeos/farmacologia , Nicotina/farmacologia , (trans)-Isômero de 3,4-dicloro-N-metil-N-(2-(1-pirrolidinil)-ciclo-hexil)-benzenoacetamida/farmacologia , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Relação Dose-Resposta a Droga , Injeções Intraventriculares , Injeções Subcutâneas , Masculino , Mecamilamina/farmacologia , Agonistas Nicotínicos/farmacologia , Antagonistas Nicotínicos/farmacologia , Peptídeos Cíclicos/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores Opioides kappa/agonistas , Síndrome de Abstinência a Substâncias/prevenção & controle , Fatores de Tempo
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