Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 49
Filtrar
1.
Sci Total Environ ; 750: 142283, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33182218

RESUMO

The deterioration of monument or building stone materials is mostly due to the growth of black crusts that cause blackening and disaggregation of the exposed surface. This study reports on new oxygen (δ17O, δ18O and Δ17O) and sulphur (δ33S, δ34S, δ36S, Δ33S and Δ36S) isotopic analyses of black crust sulphates formed on building stones in Sicily (Southern Italy). The measurements are used to identify the possible influence of volcanic emissions on black crust formation. Black crusts were mostly sampled on carbonate stone substrate in different locations subject to various sulphur emission sources (marine, anthropogenic and volcanic). Unlike atmospheric sulphate aerosols that mostly exhibit Δ33S > 0‰, here most of the analysed black crust sulphates show negative Δ33S. This confirms that black crust sulphates do not result from deposition of sulphate aerosols or of rainwater but mostly from the oxidation of dry deposited SO2 onto the stone substrate. The δ34S and δ18O values indicate that most of black crust sulphate originates from anthropogenic activities. Δ17O values are found to be related to the sampling location. The largest 17O-anomalies (up to ~4‰) are measured in black crust from areas highly influenced by volcanic emissions, which demonstrates the strong involvement of ozone in the formation of black crusts in volcanically influenced environments.

2.
Bull Entomol Res ; 100(3): 247-54, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20170592

RESUMO

Insect population dynamics depend strongly on environmental factors. For floodwater mosquitoes, meteorological conditions are crucial in the rhythm of mosquito abundances. Indeed, rainfall triggers the egg hatching after flooding breeding sites, and temperature controls the duration of the aquatic immature development up to adult emergence. According to this, we have developed a simple mechanistic and tractable model that describes the population dynamics of floodwater mosquitoes as a function only of the most accessible meteorological variables, rainfall and temperature. The model involves three parameters: development duration tdev of the immature aquatic stages, the adult emergence rate function f(t) (characterized by the emergence time scale tau and shaping the profile of adult population abundance), and the depletion rate, alpha, of adult disappearance. The developed model was subsequently applied to fit experimental field data of the dynamics of Aedes caspius (Pallas), the main pest mosquito in southern France. First, it was found that the emergence rate function of adult mosquitoes very well reproduce experimental data of the dynamics of immature development for all sampled temperatures. The estimated values of tdev and tau both exhibit Arrhenius behaviour as a function of temperature. Second, using the meteorological records of rainfall and temperature as inputs, the model correctly fit data from a two-site CO2 trapping survey conducted in 2004 and 2005. The estimated depletion rates (summation of the mortality and the emigration rates) were found to be a concave quadratic function of temperature with a maximum of 0.5 per days at about 22 degrees C.


Assuntos
Aedes/fisiologia , Modelos Biológicos , Aedes/crescimento & desenvolvimento , Animais , Feminino , Larva , Masculino , Densidade Demográfica , Dinâmica Populacional , Pupa
3.
Parasite ; 14(3): 225-9, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17933300

RESUMO

Christophers' stages durations and effect of interrupted blood meal were investigated in laboratory to study the gonotrophic cycle of Aedes caspius (Pallas, 1771). A first experiment was done with replete females (full blood meal) and females with an interrupted blood meal. Females were then regularly dissected, the durations of Christophers' stages I, II, III, IV, V were up to 8, 8, 32, 8, 48 h, respectively. A second experiment was done with replete females, females with an interrupted blood meal and females with an interrupted blood meal completed 24 h later. Interrupted females matured 21 +/- 5 follicles, interrupted-completed females 92 +/- 11, and replete females 120 +/- 8 follicles.


Assuntos
Aedes/fisiologia , Comportamento Alimentar/fisiologia , Estágios do Ciclo de Vida/fisiologia , Oogênese/fisiologia , Oviposição/fisiologia , Aedes/anatomia & histologia , Animais , Sangue , Feminino , Reprodução , Fatores de Tempo
4.
Br J Sports Med ; 39(5): e23, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15849276

RESUMO

OBJECTIVES: To develop a valid and reliable internet based lifestyle physical activity questionnaire suitable for use among the United Kingdom population. METHODS: After a detailed content analysis and item generation using a panel of experts, an internet based measure of lifestyle physical activity behaviour was developed. Data were collected from 1369 subjects in total. Confirmatory factor analysis was used to examine the two subscales of the Brunel lifestyle physical activity questionnaire among independent samples and by use of multisample analyses. RESULTS: The confirmatory factor analysis showed the psychometric integrity of two subscales: planned physical activity and unplanned physical activity. CONCLUSION: The questionnaire is a valid and reliable instrument designed to provide an online behavioural assessment to be used in conjunction with a 12 week personalised fitness programme delivered through the internet.


Assuntos
Exercício Físico , Internet , Estilo de Vida , Aptidão Física , Inquéritos e Questionários , Adulto , Feminino , Indicadores Básicos de Saúde , Humanos , Atividades de Lazer , Masculino , Projetos Piloto , Reprodutibilidade dos Testes
5.
J Aging Health ; 10(4): 441-57, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10346694

RESUMO

The purpose of the study was to compare the relative merits of two approaches to the measurement of perceived behavioral control for the prediction of attendance in an exercise program in an elderly population. The first approach was to conceptualize perceived behavioral control in the traditional manner outlined by Ajzen (1987). The second approach was to conceptualize control beliefs as two distinct constructs: scheduling self-efficacy and perceived barriers to exercise. Participants (N = 157, average age = 68 years +/-7.87, 74% female) were volunteers from elderly exercise classes. Participants were asked to complete questionnaires assessing the constructs at Weeks 5 and 9 of a 16-week exercise program. Attendance was monitored and used as the dependent variable. Results revealed that in an active elderly sample, (a) scheduling self-efficacy is a superior conceptualization for control beliefs than perceived behavioral control, (b) neither attitude nor subjective norm predict intention or attendance in an exercise program, and (c) perceived barriers to exercise are not related to exercise intention or attendance.


Assuntos
Idoso/psicologia , Exercício Físico/psicologia , Comportamentos Relacionados com a Saúde , Conhecimentos, Atitudes e Prática em Saúde , Feminino , Humanos , Masculino , Modelos Psicológicos , Ontário , Autoeficácia , Inquéritos e Questionários
6.
J Mot Behav ; 3(2): 105-9, 1971 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15155168

RESUMO

The specificity versus generality of motor performance and motor response consistency ws investigated as a function of age. 120 Ss, 30 each at age 7, 11, 15 and 19 yr., were given 120 practice trials (60 trials per session with 24 hr. interpolated between sessions) on both simple and choice RT tasks. For motor performance the reliability of individual differences were high in both tasks at all ages, while the amount of generality was moderately high in the two younger groups but diminished with age. The reliability coefficients for motor response consistency were low for both tasks but, with two exceptions, statistically significant. There was no evidences for generality in motor response consistency at any age.

7.
J Mot Behav ; 3(2): 181-8, 1971 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15155171

RESUMO

Martens has presented and excellent and provocative paper in an extremely interesting area. He has certainly outlined most of the complexities of anxiety, discussed the limitations and strengths of various theoretical approaches to its study, and has presented alternatives to existing methods. My approach has been to try to summarize what I have held to be the major problem ares or limiting factors in the study of state anxiety (stress) and motor performance and then incorporate these problem areas into the context of Marten's conclusions.

8.
J Mot Behav ; 8(4): 297-304, 1976 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23961933

RESUMO

The present investigation examined the effects of initial habit strength differences upon performance in a coaction situation. During a training session, a habit-strength hierarchy was developed in each of three groups through the establishment of a differential response expectancy for each of four alternative responses. In a subsequent test session, both performance and consistency of performance were affected by the pretraining on the correct habit. However, there was no statistical support for the hypothesis that coaction would interact with the habit-strength condition resulting in an improvement in the coaction/habit-correct group and a decrement in the coaction/habit-incorrect group. Similarly, no differences were found between the coaction and alone conditions.

9.
J Mot Behav ; 2(2): 140-8, 1970 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23941271

RESUMO

2 groups of 50 Ss practiced a pursuit rotor skill under different schedules of practice. A massed practice (MP) group (40 sec. work, 20 sec. rest) performed just as well as a distributed practice (DP) group (20 sec. work, 20 sec. rest) on the first day of practice. However, after 24 hr. of interpolated rest MP Ss demonstrated significantly greater amounts of learning. A further analysis of the 15 high initial ability and 15 low initial ability Ss from each of the two main groups resulted in no statistical differences among these subgroups in Day 1 performance that could be attributed to the practice schedules; however, a significant Ability Level × Practice Schedule interaction was obtained for Day 2 performance. It was caused by the low ability Ss under MP learning relatively more than the high ability Ss under MP when compared to the two DP groups. Thus learning was seen as being a function not only of schedule of practice but also of initial ability level.

10.
J Mot Behav ; 2(4): 239-44, 1970 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23941318

RESUMO

150 Ss were given 50 practice trials on the stabilometer over a period of 4 days (20 trials on Day 1 followed by a 1-day rest, 10 trials on Day 2, followed by a 7-day rest, 10 trials on Day 3 followed by a 14-day rest, and 10 trials on Day 4). A series of learning scores reflecting improvement in performance over the 4 days and retention scores reflecting loss of performance between days were obtained. The reliability of individual differences in these scores were calculated using the odd-even method and by progressively increasing the number of trials included in the measure of initial and final performance level. On the basis of the findings obtained it was concluded that using 4 - 6 trials in initial and final ability levels results in a difference (criterion) score which combines relatively high reliability with a relatively high estimate of the amount of change in performance.

11.
J Mot Behav ; 1(4): 275-83, 1969 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23941171

RESUMO

In investigating Eysenck's (1965) suggestion of the specificity of reminiscence, 50 high school boys were tested on 2 gross motorcoordination tasks-one involving tracking and the other balance. In the practice schedule, which was identical for both tasks, all Ss were given 20 50-sec. trials with a 10-sec. intertrial rest. A 5-min. interpolated rest was given after every fourth trial. The reliability of individual differences in reminiscence for both tasks was found to be extremely low. While Eysenck's hypothesis was not necessarily weakened, doubt was cast upon the specificity of reminiscence in the usual context of the word.

12.
J Mot Behav ; 3(1): 62-8, 1971 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23941350

RESUMO

40 college males were sequentially assigned to 1 of 2 groups to examine the effects of induced physical fatigue upon the performance and learning of a gross motor task, the stabilometer. All Ss were given 32 practice trials over 3 practice sessions, with 48 hr. rest interpolated between sessions. Trials 1 and 2 were performed under control conditions (no fatigue) for both groups. The Experimental Group was then required to perform under conditions of physical fatigue during Trials 3-26. Trials 27-32 (Session 3) were performed under control conditions. The condition of fatigue was achieved on Trials 3-26 by having Ss pedal a bicycle ergometer until a heart rate of 180 beats/min was attained prior to each trial. The Control Group cancelled vowels. The results indicated that physical fatigue was detrimental to the performance and learning of the Experimental Group.

13.
J Sci Med Sport ; 1(1): 29-37, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9732119

RESUMO

The purpose of the study was to investigate the relationship between game location and precompetition psychological states. Male rugby players (N = 100) completed the Competitive State Anxiety Inventory-2 and the Profile of Mood States approximately 1 hr before a home and an away game. Repeated measures multivariate analysis of variance of mood and anxiety scores indicated significant differences between home and away locations. Participants scored higher on Vigor and Self-confidence, and lower on Tension, Depression, Anger, Fatigue, Confusion, Cognitive Anxiety, and Somatic Anxiety when competing at home. The findings support the proposal (Courneya & Carron, 1992) that psychological states are influenced by game location.


Assuntos
Ansiedade/psicologia , Meio Ambiente , Futebol Americano/psicologia , Transtornos do Humor/psicologia , Adulto , Análise de Variância , Ansiedade/diagnóstico , Humanos , Masculino , Transtornos do Humor/diagnóstico , Escalas de Graduação Psiquiátrica , Reprodutibilidade dos Testes
14.
J Am Med Dir Assoc ; 1(4): 159-63, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-12816554

RESUMO

OBJECTIVES: To determine the carriage rate of Staphylococcus aureus (SA), both methicillin sensitive, and methicillin resistant (MRSA), among employees of a nursing home in the absence of an epidemic. DESIGN: Observational study. SETTING: A 210-bed suburban skilled nursing facility with a low endemic rate of SA infection. PARTICIPANTS: Seventy-three asymptomatic employees recruited in two waves. MEASUREMENT: Nasal swabs were cultured for SA; DNA strain typing was performed on MRSA isolates from the first wave of recruits. RESULTS: 21 of 73 (29%) cultures were positive for SA. Ten of these 21 (14% of participating employees) had nasal carriage of MRSA. MRSA carriage was not significantly correlated with age, duration of employment, or job type (clinical vs. non-clinical), and DNA strain typing suggested that employee carriage of MRSA was not the result of a common source. CONCLUSIONS: Staphylococcus aureus nasal carriage is common among skilled nursing facility personnel, and MRSA accounts for a substantial proportion of SA carriage among employees, even in the absence of an epidemic. Further research is needed to determine whether the high SA carriage rates among employees reflects work place acquisition, and, if so, whether it poses a hazard to the employees. The low incidence of nosocomial MRSA infections around the time of the study suggests that with usual infection control practices (eg, hand washing), MRSA-colonized caregivers pose little risk to nursing facility residents.

15.
Parasite ; 8(2 Suppl): S133-5, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11484336

RESUMO

Pigs infected with T. spiralis and T. britovi were followed by double (IgG) and triple antibody ELISA (IgG1, IgG2 and IgM) during a 12-week-period. Specific IgG and IgG1 responses were similar and showed a significant relation with the infecting doses and intensity of infection. Response to T. britovi was slightly lower than in groups infected with the same dose of T. spiralis. IgG2 response was weak and almost undetectable in the lowest infected pigs, but relationship with the intensity of infection was unclear. IgM antibodies showed rapid but transient increases, generally simultaneous to peaks of IgG response.


Assuntos
Anticorpos Anti-Helmínticos/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Doenças dos Suínos/imunologia , Suínos/imunologia , Trichinella spiralis/imunologia , Trichinella/imunologia , Triquinelose/veterinária , Animais , Formação de Anticorpos , Ensaio de Imunoadsorção Enzimática , Isotipos de Imunoglobulinas/sangue , Larva/imunologia , Doenças dos Suínos/parasitologia , Fatores de Tempo , Triquinelose/imunologia
16.
Percept Mot Skills ; 40(3): 727-34, 1975 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1178356

RESUMO

Cattell's High School Personality Questionnaire and Gough's Adjective Checklist were administered to 73 15-yr.-old boys to compare personality for groups selected on the basis of extreme scores on maturation (skeletal development, age at achievement of peak height velocity), body type (body somatotype, body skinfolds), performance (body reaction time), strength, physical fitness and socioeconomic status. Multiple discriminant analyses indicated that the only significant difference in personality between groups was for early versus late maturers (skeletal development) on Cattell's scale. The personality scores for the remaining extreme groups did not differ on either of the scales, Cattell's or Gough's.


Assuntos
Desenvolvimento Infantil , Personalidade , Adolescente , Crescimento , Humanos , Masculino , Aptidão Física , Classe Social , Somatotipos
17.
Environ Sci Pollut Res Int ; 21(15): 9251-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24723354

RESUMO

Glass materials are broadly used in the built environment (windows, facades, roofs, museum showcases, and solar panels) due to their optical (transparency) and thermal properties. Their interaction with the multiphase atmospheric medium results in a more or less pronounced transparency loss called soiling. This phenomenon leads to a loss of amenity of artefacts; consequently, high cleaning costs have to be supported by public and private entities. Complete understanding of the nature of surface deposit appears thus extremely important for addressing strategies to control it. The present research is based on the sheltered exposure, in different environments, of durable glass panels during 1 year. At these different locations, airborne pollutant concentrations have also been monitored. Three environments have been investigated: rural (R), urban (U) and industrial (I). Results show that the mass of the deposit and the optical impairment of the glass (haze) are too spread to allow discriminating between different environments. However, the analyses of soluble species and particulate organic matter allow identifying factors responsible for soiling and highlighted the reactivity of deposit to relative humidity which favours post-deposit evolution.


Assuntos
Vidro/química , Poluentes Atmosféricos/análise , Cidades , Meio Ambiente , Indústrias , População Rural
18.
Arch Soc Esp Oftalmol ; 88(9): 345-51, 2013 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-23988041

RESUMO

OBJECTIVE: To determine the efficacy of topical 0.3% ciprofloxacin in reducing conjunctival biota in patients undergoing cataract surgery. PATIENTS AND METHODS: Experimental, prospective, randomized, controlled and single-blind study. Forty-six eyes of 46 patients were randomized into 2 groups, the study group (n=23) received topical 0.3% ciprofloxacin one day before surgery for six times, and on the day of the surgery one drop every 15minutes starting one hour before surgery until 3 doses were completed. The control group (n=23) did not receive any antibiotics. For both groups for the surgical field 10% povidone-iodine was applied. Samples from the conjunctiva were taken at four different times and then cultured on solid media (chocolate agar, blood agar) and enrichment broth (thioglycolate). The aqueous humor samples were also cultured in thioglycolate. The presence of bacteria was identified quantitatively and qualitatively, and the frequency of contamination was measured by considering the presence of bacteria in liquid and solid culture media. The number of colony forming units (CFU) was counted in the solid culture medium. RESULTS: Positive cultures were obtained in 82.6% and 78.2% of the patients in the study and control groups, respectively, before the administration of 0.3% ciprofloxacin. The administration of 0.3% ciprofloxacin significantly reduced the CFU compared to the control group (P<.05). Immediately after the use of povidone-iodine, the proportion of patients with a positive culture decreased to 21.7% in the study group, and 8.7% in the control group. At the end of the surgery, this percentage was 26% and 30.4%, respectively. The most common isolated pathogen was negative-coagulase Staphylococcus (66.7%). CONCLUSION: The administration of 0.3% ciprofloxacin reduces conjunctival bacterial load in the preoperative period. However, it was unable to eradicate the bacteria completely. The administration of povidone-iodine reduced conjunctival biota in 50%-70% of patients undergoing cataract surgery.


Assuntos
Antibacterianos/farmacologia , Extração de Catarata , Ciprofloxacina/farmacologia , Túnica Conjuntiva/microbiologia , Microbiota/efeitos dos fármacos , Cuidados Pré-Operatórios , Administração Oftálmica , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/administração & dosagem , Humor Aquoso/microbiologia , Bactérias/isolamento & purificação , Carga Bacteriana , Ciprofloxacina/administração & dosagem , Resistência Microbiana a Medicamentos , Endoftalmite/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/prevenção & controle , Povidona-Iodo/administração & dosagem , Povidona-Iodo/farmacologia , Estudos Prospectivos , Método Simples-Cego , Infecção da Ferida Cirúrgica/prevenção & controle
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa