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1.
Ann R Coll Surg Engl ; 103(7): 478-480, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34192500

RESUMEN

BACKGROUND: There is limited evidence on perioperative outcomes of surgical patients during the COVID-19 pandemic to inform continued operating into the winter period. METHODS: We retrospectively analysed the rate of 30-day COVID-19 transmission and mortality of all surgical patients in the three hospitals in our trust in the East of England during the first lockdown in March 2020. All patients who underwent a swab were swabbed on or 24 hours prior to admission. RESULTS: There were 4,254 patients and an overall 30-day mortality of 0.99%. The excess surgical mortality in our region was 0.29%. There were 39 patients who were COVID-19 positive within 30 days of admission, 12 of whom died. All 12 were emergency admissions with a length of stay longer than 24 hours. There were three deaths among those who underwent day case surgery, one of whom was COVID-19 negative, and the other two were not swabbed but not suspected to have COVID-19. There were two COVID-19 positive elective cases and none in day case elective or emergency surgery. There were no COVID-19 positive deaths in elective or day case surgery. CONCLUSIONS: There was a low rate of COVID-19 transmission and mortality in elective and day case operations. Our data have allowed us to guide patients in the consent process and provided the evidence base to restart elective and day case operating with precautions and regular review. A number of regions will be similarly affected and should perform a review of their data for the winter period and beyond.


Asunto(s)
Procedimientos Quirúrgicos Ambulatorios/mortalidad , COVID-19/epidemiología , Procedimientos Quirúrgicos Electivos/mortalidad , Tratamiento de Urgencia/mortalidad , Procedimientos Quirúrgicos Ambulatorios/normas , Procedimientos Quirúrgicos Ambulatorios/estadística & datos numéricos , COVID-19/complicaciones , COVID-19/diagnóstico , COVID-19/transmisión , Prueba de COVID-19/normas , Prueba de COVID-19/estadística & datos numéricos , Procedimientos Quirúrgicos Electivos/normas , Procedimientos Quirúrgicos Electivos/estadística & datos numéricos , Servicio de Urgencia en Hospital/normas , Servicio de Urgencia en Hospital/estadística & datos numéricos , Tratamiento de Urgencia/normas , Tratamiento de Urgencia/estadística & datos numéricos , Inglaterra/epidemiología , Femenino , Mortalidad Hospitalaria , Humanos , Incidencia , Control de Infecciones/normas , Control de Infecciones/estadística & datos numéricos , Tiempo de Internación/estadística & datos numéricos , Masculino , Pandemias/prevención & control , Pandemias/estadística & datos numéricos , Admisión del Paciente/normas , Admisión del Paciente/estadística & datos numéricos , Estudios Retrospectivos , SARS-CoV-2/aislamiento & purificación , Medicina Estatal/normas , Medicina Estatal/estadística & datos numéricos
2.
Clin Infect Dis ; 73(7): e2234-e2242, 2021 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-32936919

RESUMEN

BACKGROUND: Integrase strand transfer inhibitor (INSTI)-based combination antiretroviral therapy (cART) is associated with greater weight gain among persons with human immunodeficiency virus (HIV), though metabolic consequences, such as diabetes mellitus (DM), are unclear. We examined the impact of initial cART regimen and weight on incident DM in a large North American HIV cohort (NA-ACCORD). METHODS: cART-naive adults (≥18 years) initiating INSTI-, protease inhibitor (PI)-, or nonnucleoside reverse transcriptase inhibitor (NNRTI)-based regimens from January 2007 through December 2017 who had weight measured 12 (±6) months after treatment initiation contributed time until clinical DM, virologic failure, cART regimen switch, administrative close, death, or loss to follow-up. Multivariable Cox regression yielded adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for incident DM by cART class. Mediation analyses, with 12-month weight as mediator, similarly adjusted for all covariates. RESULTS: Among 22 884 eligible individuals, 47% started NNRTI-, 30% PI-, and 23% INSTI-based cART with median follow-up of 3.0, 2.3, and 1.6 years, respectively. Overall, 722 (3%) developed DM. Persons starting INSTIs vs NNRTIs had incident DM risk (HR, 1.17 [95% CI, .92-1.48]), similar to PI vs NNRTI initiators (HR, 1.27 [95% CI, 1.07-1.51]). This effect was most pronounced for raltegravir (HR, 1.42 [95% CI, 1.06-1.91]) vs NNRTI initiators. The INSTI-DM association was attenuated (HR, 1.03 [95% CI, .71-1.49] vs NNRTIs) when accounting for 12-month weight. CONCLUSIONS: Initiating first cART regimens with INSTIs or PIs vs NNRTIs may confer greater risk of DM, likely mediated through weight gain.


Asunto(s)
Fármacos Anti-VIH , Diabetes Mellitus , Infecciones por VIH , Inhibidores de Integrasa VIH , Adulto , Fármacos Anti-VIH/uso terapéutico , Canadá , Diabetes Mellitus/tratamiento farmacológico , Diabetes Mellitus/epidemiología , VIH , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Inhibidores de Integrasa VIH/uso terapéutico , Humanos , Inhibidores de la Transcriptasa Inversa/efectos adversos , Estados Unidos/epidemiología , Carga Viral , Aumento de Peso
3.
AIDS Behav ; 23(3): 627-635, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30368620

RESUMEN

Symptom distress remains a challenging aspect of living with HIV. Physical activity is a promising symptom management strategy, but its effect on symptom distress has not been examined in a large, longitudinal HIV-infected cohort. We hypothesized that higher physical activity intensity would be associated with reduced symptom distress. We included 5370 people living with HIV (PLHIV) who completed patient-reported assessments of symptom distress, physical activity, alcohol and substance use, and HIV medication adherence between 2005 and 2016. The most frequent and burdensome symptoms were fatigue (reported by 56%), insomnia (50%), pain (46%), sadness (45%), and anxiety (45%), with women experiencing more symptoms and more burdensome symptoms than men. After adjusting for age, sex, race, time, HIV medication adherence, alcohol and substance use, site, and HIV RNA, greater physical activity intensity was associated with lower symptom intensity. Although individual symptoms may be a barrier to physical activity (e.g. pain), the consistent association between symptoms with physical activity suggests that more intense physical activity could mitigate symptoms experienced by PLHIV.


Asunto(s)
Ansiedad/epidemiología , Ejercicio Físico , Fatiga/epidemiología , Infecciones por VIH/psicología , Cumplimiento de la Medicación/psicología , Adulto , Estudios de Cohortes , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Dolor/epidemiología , Trastornos del Inicio y del Mantenimiento del Sueño , Estrés Psicológico/epidemiología , Adulto Joven
4.
J Stroke Cerebrovasc Dis ; 25(2): 288-91, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26654667

RESUMEN

BACKGROUND: Like all medical innovations, telestroke must demonstrate successful outcomes to achieve sustained growth and acceptance. Asserting that telemedicine is faster, employs the latest technology, or promotes a better use of limited resources is laudable but insufficient. An analysis of stroke treatment within a telemedicine network in 2013 showed that tissue-type plasminogen activator (tPA) could be safely and reliably administered within a practice-based model of telestroke care. Since then, hospital volume and tPA administration within this network have tripled. We hypothesize that a practice-based model of telestroke can maintain positive outcomes in the face of rapid growth. METHODS: Data on tPA treatment times and outcomes after thrombolysis were gathered for 165 patients treated with alteplase between November 2012 and November 2014. Comparisons were made to a previous published study of 54 patients seen between October 2010 and October 2012 in the same network. Primary outcome measures were average door-to-needle (DTN) time for TPA administration and average call-to-needle (CTN) time. RESULTS: Significant reductions were observed in median DTN (93 versus 75 minutes, P < .01) and median CTN (56 versus 41 minutes, P < .01). Quality outcome measures such as post-tPA symptomatic hemorrhage (2 [4%] versus 9 [5%], P = .23), length of stay (4 versus 4 days, P = .45), mortality (8 [15%] versus 16 [10%]; P = .32), and percentage of stroke patients treated remained stable. CONCLUSIONS: This study shows that a practice-based telemedicine system can produce meaningful improvement in markers of telestroke efficiency in the face of rapid growth of a telestroke network.


Asunto(s)
Isquemia Encefálica/tratamiento farmacológico , Fibrinolíticos/uso terapéutico , Accidente Cerebrovascular/tratamiento farmacológico , Telemedicina , Terapia Trombolítica , Activador de Tejido Plasminógeno/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mejoramiento de la Calidad , Factores de Tiempo , Tiempo de Tratamiento , Resultado del Tratamiento , Adulto Joven
5.
Int J Clin Pract ; 69(5): 618-22, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25650874

RESUMEN

BACKGROUND: Synovial fluid analysis is an indispensable investigation to attain a diagnosis in a patient with acute hot swollen joint(s), septic arthritis in particular. A delay in appropriate early management results in serious undesired consequences. METHODS: We evaluated clinical practice at two teaching hospitals including 81 patients. We analysed medical records, laboratory pathology results and discharge summaries with regard to documentation of joint aspiration, blood cultures, antibiotic treatment and specialist referral. We then conducted a survey of 140 medical trainees to evaluate their self-reported competence at managing the acute hot swollen joint. RESULTS: We found that synovial aspiration and blood cultures were performed in only 42(52%) and 30(37%) patients, respectively, not in accord with current guidelines. Given trainee doctors are responsible for the early management of acute hot swollen joint(s), our survey reveal low self-reported levels of competence and confidence at managing acute hot swollen joint(s) in 72(52%) and 37(27%) respondents, respectively. Furthermore, 101(75%) trainees indicated a need for more training in joint aspiration. We also report that 13 of 15 hospitals surveyed in London and South East UK do not provide specific training on the management of the hot swollen joint and joint aspiration as part of their induction programme. CONCLUSIONS: Early management of patients with hot swollen joint(s) to perform synovial fluid aspiration and blood cultures are not being done in accordance with guidelines. We suggest that the medical trainee curricula should incorporate joint aspiration skills as an 'essential procedure', to improve the trainee doctor's confidence and competence at managing acute hot swollen joint(s) to improve adherence to guidelines, and consequently, patient outcomes.


Asunto(s)
Artritis Infecciosa/terapia , Competencia Clínica , Evaluación de Resultado en la Atención de Salud , Guías de Práctica Clínica como Asunto , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Artritis Infecciosa/patología , Biopsia con Aguja Fina/normas , Femenino , Hospitales de Enseñanza , Humanos , Londres , Masculino , Persona de Mediana Edad , Atención Primaria de Salud , Índice de Severidad de la Enfermedad , Medicina Estatal , Adulto Joven
6.
Poult Sci ; 94(3): 552-7, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25480736

RESUMEN

This article reports the first publicly available egg production costs compared across 3 hen-housing systems. We collected detailed data from 2 flock cycles from a commercial egg farm operating a conventional barn, an aviary, and an enriched colony system at the same location. The farm employed the same operational and accounting procedures for each housing system. Results provide clear evidence that egg production costs are much higher for the aviary system than the other 2 housing systems. Feed costs per dozen eggs are somewhat higher for the aviary and lower for the enriched house compared with the conventional house. Labor costs are much lower for the conventional house than the other 2, and pullet costs are much higher for the aviary. Energy and miscellaneous costs are a minimal part of total operating costs and do not differ by housing system. Total capital investments per hen-capacity are much higher for the aviary and the enriched house. Capital costs per dozen eggs depend on assumptions about appropriate interest and depreciation rates. Using the same 10% rate for each housing system shows capital costs per dozen for the aviary and the enriched housing system are much higher than capital costs per dozen for the conventional house. The aviary has average operating costs (feed, labor, pullet, energy, and miscellaneous costs that recur for each flock and vary with egg production) about 23% higher and average total costs about 36% higher compared with the conventional house. The enriched housing system has average operating costs only about 4% higher compared with the conventional house, but average total costs are 13% higher than for the conventional house.


Asunto(s)
Crianza de Animales Domésticos/economía , Pollos/fisiología , Huevos/economía , Vivienda para Animales/economía , Alimentación Animal/economía , Bienestar del Animal/economía , Animales , Costos y Análisis de Costo , Femenino , Reproducción
7.
Biopolymers ; 101(4): 329-35, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23907817

RESUMEN

Type I collagen is a fibril-forming protein largely responsible for the mechanical stability of body tissues. The tissue level properties of collagen have been studied for decades, and an increasing number of studies have been performed at the fibril scale. However, the mechanical properties of collagen at the molecular scale are not well established. In the study presented herein, the persistence length of pepsin digested bovine type I collagen is extracted from the conformations assumed when deposited from solution onto two-dimensional surfaces. This persistence length is a measure of the flexibility of the molecule. Comparison of the results for molecules deposited from different solvents allows for the study of the effect of the solutions on the flexibility of the molecule and provides insight into the molecule's behavior in situ.


Asunto(s)
Colágeno Tipo I/química , Solventes/química , Animales , Tampones (Química) , Bovinos , Microscopía de Fuerza Atómica , Nanopartículas/química , Agua/química
8.
J Stroke Cerebrovasc Dis ; 22(8): e546-8, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23834847

RESUMEN

Emergency stroke treatment would benefit from the increased use of thrombolysis via academic or practice-based telemedicine systems. However, a comparative analysis of these systems has not been undertaken. Data on stroke severity and outcomes after thrombolysis were gathered on patients treated by a practice-based system and compared to published data from academic systems. Patient demographics and outcome measures were not significantly different for patients treated by practice-based or academic providers with the exceptions of lower age and shorter duration of stay in the practice-based treatment group. This study shows that emergency stroke care provided by academic and practice-based telemedicine systems can achieve similar outcomes.


Asunto(s)
Centros Médicos Académicos , Servicios Médicos de Urgencia , Fibrinolíticos/administración & dosificación , Accesibilidad a los Servicios de Salud , Accidente Cerebrovascular/tratamiento farmacológico , Telemedicina , Terapia Trombolítica , Activador de Tejido Plasminógeno/administración & dosificación , Administración Intravenosa , Factores de Edad , Anciano , Anciano de 80 o más Años , Evaluación de la Discapacidad , Femenino , Mortalidad Hospitalaria , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Consulta Remota , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/diagnóstico , Factores de Tiempo , Tiempo de Tratamiento , Resultado del Tratamiento
9.
J Phys Condens Matter ; 25(28): 285101, 2013 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-23751928

RESUMEN

Cross-linking between the constituent chains of biopolymers has a marked effect on their materials' properties. In certain of these materials, such as fibrillar collagen, increases in cross-linking lead to an increase in the melting temperature. Fibrillar collagen is an axially-ordered network of cross-linked polymer chains exhibiting a broadened denaturation transition, which has been explained in terms of the successive denaturation with temperature of multiple species. We model axially-ordered, cross-linked materials as stiff chains with distinct arrangements of cross-link-forming sites. Simulations suggest that systems composed of chains with identical arrangements of cross-link-forming sites exhibit critical behavior. In contrast, systems composed of non-identical chains undergo a crossover. This model suggests that the arrangement of cross-link-forming sites may contribute to the broadening of the denaturation transition in fibrillar collagen.


Asunto(s)
Modelos Moleculares , Polímeros/química , Sitios de Unión , Colágenos Fibrilares/química , Modelos Químicos , Conformación Molecular , Método de Montecarlo , Temperatura
10.
Ir Med J ; 106(4): 118-20, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23691847

RESUMEN

Legislation is being considered which bans smoking in cars carrying children under the age of 16. This was an observational survey of smoking by drivers and passengers and mobile phone use by drivers in 2,230 cars over three time periods in two Dublin locations. The observed prevalence of mobile telephone use (2.56%) was higher than smoking (1.39%) (p < 0.01), but was low in both. There was no significant variation according to time of day. There was an inverse pattern according to car value for smoking drivers (p = 0.029). Eight adult passengers and just one child were observed as being exposed to a smoking adult driver. In conclusion, the public health importance of regulating passive smoke exposure is clear but the resources required to police such a ban in vehicles may be labour intensive for the yield in detection or prevention.


Asunto(s)
Conducción de Automóvil/estadística & datos numéricos , Teléfono Celular/estadística & datos numéricos , Fumar , Adulto , Anciano , Conducción de Automóvil/legislación & jurisprudencia , Femenino , Humanos , Irlanda , Masculino , Persona de Mediana Edad , Fumar/legislación & jurisprudencia , Contaminación por Humo de Tabaco/legislación & jurisprudencia , Contaminación por Humo de Tabaco/prevención & control
12.
Phys Rev Lett ; 106(11): 110505, 2011 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-21469853

RESUMEN

We present and experimentally demonstrate a communication protocol that employs shared entanglement to reduce errors when sending a bit over a particular noisy classical channel. Specifically, it is shown that given a single use of this channel, one can transmit a bit with higher success probability when the sender and receiver share entanglement compared to the best possible strategy when they do not. The experiment is realized using polarization-entangled photon pairs, whose quantum correlations play a critical role in both the encoding and decoding of the classical message. Experimentally, we find that a bit can be successfully transmitted with probability 0.891±0.002, which is close to the theoretical maximum of (2+2(-1/2))/3≈0.902 and is significantly above the optimal classical strategy, which yields 5/6≈0.833.

13.
Poult Sci ; 90(1): 241-50, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21177466

RESUMEN

Conventional cage housing for laying hens evolved as a cost-effective egg production system. Complying with mandated hen housing alternatives would raise marginal production costs and require sizable capital investment. California data indicate that shifts from conventional cages to barn housing would likely cause farm-level cost increases of about 40% per dozen. The US data on production costs of such alternatives as furnished cages are not readily available and European data are not applicable to the US industry structure. Economic analysis relies on key facts about production and marketing of conventional and noncage eggs. Even if mandated by government or buyers, shifts to alternative housing would likely occur with lead times of at least 5 yr. Therefore, egg producers and input suppliers would have considerable time to plan new systems and build new facilities. Relatively few US consumers now pay the high retail premiums required for nonconventional eggs from hens housed in alternative systems. However, data from consumer experiments indicate that additional consumers would also be willing to pay some premium. Nonetheless, current data do not allow easy extrapolation to understand the willingness to pay for such eggs by the vast majority of conventional egg consumers. Egg consumption in the United States tends to be relatively unresponsive to price changes, such that sustained farm price increases of 40% would likely reduce consumption by less than 10%. This combination of facts and relationships suggests that, unless low-cost imports grew rapidly, requirements for higher cost hen housing systems would raise US egg prices considerably while reducing egg consumption marginally. Eggs are a low-cost source of animal protein and low-income consumers would be hardest hit. However, because egg expenditures are a very small share of the consumer budget, real income loss for consumers would be small in percentage terms. Finally, the high egg prices imposed by alternative hen housing systems raise complex issues about linking public policy costs to policy beneficiaries.


Asunto(s)
Crianza de Animales Domésticos/métodos , Bienestar del Animal/normas , Pollos , Huevos/normas , Vivienda para Animales/normas , Responsabilidad Social , Crianza de Animales Domésticos/economía , Bienestar del Animal/economía , Animales , Femenino , Alimentos/economía , Vivienda para Animales/economía , Factores de Tiempo , Estados Unidos
14.
Colloids Surf B Biointerfaces ; 67(1): 140-4, 2008 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-18815015

RESUMEN

Using a previously described method for the functionalization of glass substrates with glycosaminoglycans (GAGs), in vitro experimental comparison of adhesion levels of cancer cells to glycosaminoglycan-modified substrates was performed with non-treated and heparin-treated human cancer cells of different metastatic activity. For both non-treated and heparin-treated cells, our results indicate that heparan sulfate is the preferred substrate for adhesion while keratan sulfate shows anti-adhesive properties. The observed net effect of heparin is a cell-dependent reduction in the adhesion figures. Overall, our results suggest that tissues with higher composition of heparan sulfate chains may be preferential metastatic targets and indicate that the effective use of heparin as anti-metastatic or anti-inflammatory agent may also depend on glycosaminoglycan composition of the affected organs.


Asunto(s)
Materiales Biocompatibles Revestidos , Vidrio , Glicosaminoglicanos , Neoplasias/metabolismo , Adhesión Celular/fisiología , Línea Celular Tumoral , Materiales Biocompatibles Revestidos/metabolismo , Glicosaminoglicanos/metabolismo , Heparina/metabolismo , Humanos , Neoplasias/patología
15.
Food Chem Toxicol ; 46(6): 1905-18, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18334278

RESUMEN

Since the discovery of acrylamide in heat-treated carbohydrate-rich foods, many more heat-generated food contaminants have been identified in a variety of foods and models systems. A database of these contaminants, generated as a result of either lipid oxidation or the Maillard reaction, has recently been compiled under the HEATOX project. A large majority of the compounds has not been tested for potential adverse effects on human health, which makes it difficult to carry out adequate assessment of risks to an average consumer. This study used two in silico toxicity Expert Systems (Topkat and Derek for Windows), as a preliminary screening tool to identify potential toxicants among the heat-generated contaminants in foods or model systems. The methodology enabled prioritisation of the compounds on the basis of predicted toxicities, and identification of potential toxicants for targeted testing by standard laboratory procedures. A comparison between the predicted toxicities of selected compounds and the available experimental data indicated that the methodology can be reliably used for assessing toxicity of untested food contaminants.


Asunto(s)
Culinaria , Contaminación de Alimentos/análisis , Pruebas de Toxicidad/métodos , Animales , Pruebas de Carcinogenicidad , Carcinógenos/toxicidad , Simulación por Computador , Sistemas Especialistas , Calor , Dosificación Letal Mediana , Pruebas de Mutagenicidad , Mutágenos/toxicidad , Ratas
16.
Neuroimage ; 40(2): 884-895, 2008 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-18234522

RESUMEN

Using a sandwich-masked priming paradigm with faces, we report two ERP effects that appear to reflect different levels of subliminal face processing. These two ERP repetition effects dissociate in their onset, scalp topography, and sensitivity to face familiarity. The "early" effect occurred between 100 and 150 ms, was maximally negative-going over lateral temporoparietal channels, and was found for both familiar and unfamiliar faces. The "late" effect occurred between 300 and 500 ms, was maximally positive-going over centroparietal channels, and was found only for familiar faces. The early effect resembled our previous fMRI data from the same paradigm; the late effect resembled the behavioural priming found, in the form of faster reaction times to make fame judgments about primed relative to unprimed familiar faces. None of the ERP or behavioural effects appeared explicable by a measure of participants' ability to see the primes. The ERP and behavioural effects showed some sensitivity to whether the same or a different photograph of a face was repeated, but could remain reliable across different photographs, and did not appear attributable to a low-level measure of pixelwise overlap between prime and probe photograph. The functional significance of these ERP effects is discussed in relation to unconscious perception and face processing.


Asunto(s)
Potenciales Evocados , Cara , Procesos Mentales , Percepción Visual/fisiología , Adulto , Electrofisiología , Femenino , Humanos , Masculino , Factores de Tiempo
17.
Artículo en Inglés | MEDLINE | ID: mdl-18041596

RESUMEN

The effect of domestic preparation regimes on the level of the heat-formed toxicant furan was studied to provide useful information for exposure assessment and advice for manufacturers and consumers. Foods were cooked in a saucepan on a gas hob or microwaved and furan was determined by headspace sampling with gas chromatography-mass spectrometry. In general, furan levels did not decrease as much when foods were cooked in a microwave oven when compared with the same foods cooked in a saucepan. Furan levels decreased in most canned and jarred foods after heating in a saucepan. Low levels of furan in soups in cartons were not changed by any procedure. Furan decreased slightly in foods on standing before consumption, but did so more rapidly on stirring. The levels also decreased slightly when foods were left to stand on plates; this observation is attributed to the volatility of furan.


Asunto(s)
Carcinógenos Ambientales/análisis , Culinaria/métodos , Contaminación de Alimentos/análisis , Furanos/análisis , Calor , Adulto , Embalaje de Alimentos/métodos , Conservación de Alimentos/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Humanos , Lactante , Alimentos Infantiles/análisis
18.
Psychon Bull Rev ; 14(5): 989-93, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18087971

RESUMEN

Despite the substantial interest in memory for complex pictorial stimuli, there has been virtually no research comparing memory for static scenes with that for their moving counterparts. We report that both monochrome and color moving images are better remembered than static versions of the same stimuli at retention intervals up to one month. When participants studied a sequence of still images, recognition performance was the same as that for single static images. These results are discussed within a theoretical framework which draws upon previous studies of scene memory, face recognition, and representational momentum.


Asunto(s)
Memoria , Percepción de Movimiento , Percepción Visual , Humanos , Reconocimiento en Psicología
19.
J Nematol ; 38(1): 90-6, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19259435

RESUMEN

The virulence index of three Meloidogyne incognita field isolates to the resistance gene Rk in cowpea was 0%, 75%, and 120%, with the index measured as reproduction on resistant plants as a percentage of the reproduction on susceptible plants. Continuous culture of the 75% virulent isolate on susceptible tomato for more than 5 years (about 25 generations) resulted in virulence decline to about 4%. The rate of the decline in virulence was described by exponential decay, indicating the progressive loss of virulence on a susceptible host. The 120% virulent isolate declined to 90% virulence during five generations on susceptible cowpea. Following virulence decline, the two isolates were compared over 5 years in inoculated field microplots both separately and as a mixture on susceptible, gene Rk, and gene Rk(2) cowpea plants. At infestation of the plots, the two isolates were 1.2% and 92.0% virulent, respectively, to gene Rk and 0.2% and 8.1% virulent, respectively, to gene Rk(2). Virulence to gene Rk in the two isolates and in mixture increased under 5 years of continuous Rk cowpea plants to 129% to 172% and under Rk(2) cowpea plants to 113% to 139 % by year 5. Virulence to gene Rk(2) increased during continuous cropping with Rk cowpea plants to 42% to 47% and with Rk(2) cowpea plants to 22% to 48% by year 5. Selection of Rk(2)-virulence was slower in the isolate with low itt-virulence. The virulence to both genes Rk and Rk(2) in the mixed population was not different from that in the highly virulent isolate by year 5 of all cropping combinations. Selection of Rk(2)-virulence on plants with Rk, and vice versa, indicated at least partial overlap of gene specificity between Rk and Rk(2) with respect to selection of nematode virulence. This observation should be considered when resistance is used in cowpea rotations.

20.
J Nematol ; 38(2): 250-7, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19259455

RESUMEN

The root-knot nematode Meloidogyne incognita is a damaging pest of cotton (Gossypium hirsutum) worldwide. A major gene (rkn1) conferring resistance to M. incognita was previously identified on linkage group A03 in G. hirsutum cv. Acala NemX. To determine the patterns of segregation and phenotypic expression of rkn1, F(1), F(2), F(2:3), BC(1)F(1) and F(2:7) recombinant inbred lines (RIL) from intraspecific crosses between Acala NemX and a closely related susceptible cultivar Acala SJ-2 were inoculated in greenhouse tests with M. incognita race 3. The resistance phenotype was determined by the extent of nematode-induced root galling and nematode egg production on roots. Suppression of root galling and egg production was highly correlated among individuals in all tests. Root galling and egg production on heterozygous plants did not differ from the susceptible parent phenotype 125 d or more after inoculation, but were slightly suppressed with shorter screening (60 d), indicating that rkn1 behaved as a recessive gene or an incompletely recessive gene, depending on the screening condition. In the RIL, rkn1 segregated in an expected 1 resistant: 1 susceptible ratio for a major resistance gene. However, within the resistant class, 21 out of 34 RIL were more resistant than the resistant parent Acala NemX, indicating transgressive segregation. These results suggest that rkn1-based resistance in G. hirsutum can be enhanced in progenies of crosses with susceptible genotypes. Allelism tests and molecular genetic analysis are needed to determine the relationship of rkn1 to other M. incognita resistance sources in cotton.

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