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1.
Ergonomics ; 66(11): 1750-1767, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38009364

RESUMEN

Artificial Intelligence (AI) is being increasingly implemented within road transport systems worldwide. Next generation of AI, Artificial General Intelligence (AGI) is imminent, and is anticipated to be more powerful than current AI. AGI systems will have a broad range of abilities and be able to perform multiple cognitive tasks akin to humans that will likely produce many expected benefits, but also potential risks. This study applied the EAST Broken Links approach to forecast the functioning of an AGI system tasked with managing a road transport system and identify potential risks. In total, 363 risks were identified that could have adverse impacts on the stated goals of safety, efficiency, environmental sustainability, and economic performance of the road system. Further, risks beyond the stated goals were identified; removal from human control, mismanaging public relations, and self-preservation. A diverse set of systemic controls will be required when designing, implementing, and operating future advanced technologies.Practitioner summary: This study demonstrated the utility of HFE methods for formally considering risks associated with the design, implementation, and operation of future technologies. This study has implications for AGI research, design, and development to ensure safe and ethical AGI implementation.


Asunto(s)
Inteligencia Artificial , Tecnología , Humanos , Predicción
2.
J Anim Sci ; 95(1): 81-90, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28177378

RESUMEN

A significant number of lambs born each yr in Australia die within 72 h of birth. Periods of high wind, combined with rain and low temperatures, can lead to marked increases in the level of mortality. Under these weather conditions mortality levels may be reduced with the provision of shelter, provided it is utilized by lambs. This study used GPS collars to determine the use of shelter by ewes and lambs, to compare the movement of ewes with twin lambs across 2 types of shelter (hedgerows and shrubs), while also comparing ewes with single and twin lambs in a single shelter type (hedgerows). Additionally, the birth sites of 364 lambs and death sites of 252 lambs were recorded across the 3 shelter type and litter size combinations (Twins in shrubs, Twins in hedgerows, Singles in hedgerows) plus an unsheltered group (Singles in unsheltered). A higher (P < 0.001) than randomly expected percentage of ewes lambed in the areas closest to both shelter types; in the shrub shelter 42% of ewes lambed within 2.5 m of shrub rows compared to an expected 11% based on the proportion of the paddock this area constituted. Despite the higher than expected percentage of ewes lambing close to the shelter rows, ewes in both twin lamb shelter types avoided the areas close to the shelter before and after lambing (Hedgerows-2.5 m; Shrubs- 6.25 m) and single bearing ewes showed no preference for or against these areas. With a high proportion of twin bearing ewes lambing close to the shelter, a design that reduces the potential for ewe and offspring separation while providing good shelter will offer the greatest potential reduction in newborn twin lamb mortality arising from exposure.


Asunto(s)
Parto , Ovinos/fisiología , Animales , Animales Recién Nacidos , Australia , Conducta Animal , Femenino , Vivienda para Animales , Tamaño de la Camada , Movimiento
3.
Prostate Cancer Prostatic Dis ; 18(3): 237-41, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26171881

RESUMEN

BACKGROUND: Intraprostatic injection of ethanol has been previously tested in clinical trials as a potential treatment of BPH, with variable outcomes. As evident from animal studies, the inconsistency was owing to various degrees of ethanol backflow along the needle tract. In acute canine experiments, we previously documented that using convection enhanced delivery (CED) eliminates backflow and improves ethanol distribution. The goal of this study was to compare the diffusion pattern between a microporous hollow fiber catheter (MiHFC) and a standard needle in human prostates from organ donors. METHODS: Prostates were harvested from cadaveric organ donors immediately after removal of organs for transplant. After trimming off excess fat and weighing, prostates were injected with absolute ethanol. The total injected volume was 25% of the calculated prostate volume. One lateral lobe was injected using a single lumen 21-gauge control needle. The contralateral lobe was injected with the same volume but using a MiHFC. Immediately after injection, prostates were fixed en bloc in 10% neutral-buffered formalin, and then sectioned. Three-dimensional reconstruction was performed to determine lesion volume based on hematoxylin- and eosin-stained cross-sections. RESULTS: Three fresh human prostates were harvested and injected. The time from harvest to intraprostatic injection was 15-35 min. The lesion created by the MiHFC was 1.14±0.52 cm(3), whereas that from the control needle was 0.28±0.10 cm(3) (P=0.038). No backflow was observed along the needle tract of the MiHFC. CONCLUSIONS: This study shows that freshly harvested human prostates can be used to evaluate new treatments using intraprostatic injection. Similar to in vivo canine experiments, the ethanol lesion sizes were significantly bigger with the use of a MiHFC when compared with a standard single lumen needle.


Asunto(s)
Etanol/administración & dosificación , Inyecciones Intralesiones/métodos , Próstata/metabolismo , Difusión , Humanos , Masculino , Próstata/patología
4.
Zoonoses Public Health ; 61(5): 324-37, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23954136

RESUMEN

Cryptosporidium are ubiquitous and significant enteropathogens of all classes of vertebrates and a major cause of human morbidity and mortality worldwide. Of the 24 recognized species, the zoonotic Cryptosporidium parvum and the host-specific Cryptosporidium hominis cause the majority of cases of human cryptosporidiosis. Here, we report on structural and transcriptional variability between C. parvum and C. hominis at the MIC1 locus, which encodes a microneme localized thrombospondin-like domain containing protein previously demonstrated to be critical for host cell infection by C. parvum. We demonstrate, using reverse transcription quantitative PCR with the aid of genomic data from the EuPathDB site, that the transcribed product in C. hominis is both truncated and significantly down-regulated in the sporozoite. We hypothesize that CpMIC1 may be a genetic factor involved in facilitating the wider host range of C. parvum in comparison with the specific host range of C. hominis. Furthermore, we show that the presence of a microsatellite (ML-2) within the C. parvum MIC-1 locus enables the development of a PCR marker that can rapidly distinguish the zoonotic C. parvum from C. hominis and other significant human infectious Cryptosporidium species due to reproducible PCR slippage across the ML-2 microsatellite. Additionally, we demonstrate that this locus is tightly linked to the GP60 locus, a locus commonly used in the genetic characterization of C. parvum and C. hominis isolates. This marker should provide a robust and additional tool to aid in the rapid identification of C. parvum from other Cryptosporidium species.


Asunto(s)
Criptosporidiosis/parasitología , Cryptosporidium/genética , Reacción en Cadena de la Polimerasa/métodos , Proteínas Protozoarias/metabolismo , Animales , Cryptosporidium/clasificación , Cryptosporidium/patogenicidad , Extinción Biológica , Humanos , Repeticiones de Microsatélite , Proteínas Protozoarias/genética , Zoonosis
5.
Parasitology ; 139(12): 1533-46, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22894830

RESUMEN

Bile salts have been identified as an important trigger for excystation of Cryptosporidium oocysts but the hierarchy or synergism of this signal in relation to other triggers involved in excystation is poorly understood. In addition to excystation, bile salts have also been reported to increase the invasiveness of sporozoites within in vitro culture, possibly by affecting the secretory pathway via modification of intracellular calcium signalling. Nevertheless, incorporation of bile or bile salts into in vitro assays is not universal, with recent reports of negative effects on parasite growth. Here we report that bile and sodium taurocholate significantly affect both excystation rate and parasite in vitro growth. We demonstrate that their effect on excystation is dose, time and pre-treatment temperature dependent, while increases in parasite replication appear to be associated with modulation of parasite intracellular calcium and increased host cell susceptibility to infection. Notably, we illustrate that bile has a significant effect on host cells and can be cytotoxic at concentrations not much higher than those currently used for in vitro assays. This work should assist with more rational design of in vitro culture systems, with significant considerations for assay format when incorporating bile or bile salts as an excystation trigger.


Asunto(s)
Bilis/metabolismo , Cryptosporidium parvum/fisiología , Animales , Bovinos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cryptosporidium parvum/efectos de los fármacos , Cryptosporidium parvum/patogenicidad , Humanos , Oocistos/efectos de los fármacos , Oocistos/fisiología , Transducción de Señal/efectos de los fármacos , Ácido Taurocólico/farmacología , Temperatura , Factores de Tiempo
6.
Anim Reprod Sci ; 131(1-2): 9-22, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22386690

RESUMEN

The positive effects of fat and energy supplementation on improvements in reproduction are well documented. However, the specific effects of omega-3 polyunsaturated fatty acids (n-3) on reproductive success in ruminants have not been examined in detail. While the link between n-3 and markers associated with reproduction, in particular, prostaglandin F(2α) (PGF(2α)) and the link between PGF(2α) and reproductive outcomes are well established, evidence of a direct effect of high n-3 diets on measurable reproductive outcomes in ruminants is lacking. Therefore, the aim of the current review was to examine the effect of n-3 on a number of reproductive markers and measurable outcomes in sheep and cattle. There is strong evidence linking consumption of diets high in n-3 with reduced circulating peripheral inflammatory markers such as PGF(2α). Inflammatory eicosanoids including PGF(2α), in particular, can significantly affect reproduction outcomes such as the onset of oestrus, embryo survival and parturition. While there is also evidence linking n-3 supplementation with longer time to oestrus and parturition associated with reduced PGF(2α), the effects of n-3 on other measurable outcomes of reproductive success, such as pregnancy rate, embryo survival and intergenerational effects on the health and production of offspring are largely unknown. Similarly, the effects of diets high in n-3 or n-6 polyunsaturated fatty acids on male fertility are also unknown.


Asunto(s)
Bovinos/fisiología , Ácidos Grasos Omega-3/farmacología , Ácidos Grasos Omega-6/farmacología , Prostaglandinas/fisiología , Reproducción/fisiología , Ovinos/fisiología , Animales , Animales Recién Nacidos , Estradiol/sangre , Femenino , Oocitos/fisiología , Folículo Ovárico/fisiología , Progesterona/sangre , Prostaglandinas/sangre , Ovinos/sangre
7.
Appl Clin Inform ; 3(2): 175-85, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23620718

RESUMEN

Electronic physician documentation is an essential element of a complete electronic medical record (EMR). At Lucile Packard Children's Hospital, a teaching hospital affiliated with Stanford University, we implemented an inpatient electronic documentation system for physicians over a 12-month period. Using an EMR-based free-text editor coupled with automated import of system data elements, we were able to achieve voluntary, widespread adoption of the electronic documentation process. When given the choice between electronic versus dictated report creation, the vast majority of users preferred the electronic method. In addition to increasing the legibility and accessibility of clinical notes, we also decreased the volume of dictated notes and scanning of handwritten notes, which provides the opportunity for cost savings to the institution.

8.
Parasitology ; 138(6): 671-81, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21414244

RESUMEN

Members of the genus Cryptosporidium, which cause the gastrointestinal disease cryptosporidiosis, still represent a significant cause of water-borne disease worldwide. While intensive efforts have been invested in the development of techniques for parasite culture, in vitro growth has been hampered by a number of factors including low levels of infectivity as well as delayed life-cycle development and poor synchronicity. In this study we examined factors affecting the timing of contact between excysted sporozoites and target host cells and the subsequent impact of this upon the establishment of infection. We demonstrate that excystation rate impacts upon establishment of infection and that in our standard assay format the majority of sporozoites are not close enough to the cell monolayer when they are released from the oocyst to successfully establish infection. However, this can be easily overcome by centrifugation of oocysts onto the cell monolayer, resulting in approximately 4-fold increases in sporozoite attachment and subsequent infection. We further demonstrate that excystation procedures can be tailored to control excystation rate to match the assay end purpose and that excystation rate can influence data interpretation. Finally, the addition of both a centrifugation and washing step post-sporozoite attachment may be appropriate when considering the design of in vitro culture experiments for developmental analysis and stage-specific gene expression as this appears to increase the synchronicity of early developmental stages.


Asunto(s)
Técnicas de Cultivo de Célula , Criptosporidiosis/parasitología , Cryptosporidium parvum/fisiología , Parasitología/métodos , Animales , Línea Celular Tumoral , Humanos , Oocistos/fisiología , Esporozoítos/fisiología , Tiempo
9.
Anim Reprod Sci ; 121(3-4): 242-8, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20678872

RESUMEN

This study evaluated the ability of short-term grazing of live=green pasture to increase ovulation rate during late summer when annual pasture is generally dead and of low quality. Ovulation rates, measured by the number of corpora lutea, were compared between 4 nutritional treatments: senesced phalaris (Phalaris aquatica), phalaris plus 500g lupin grain per day, lucerne (Medicago sativa) or chicory (Chicorum intybus) pastures. The study used 100 Merino ewes per treatment, divided between 2 replicates. The experiment was repeated in 3 years; February 2006, and January 2007 and 2008. Oestrus was synchronised and the ewes grazed the pastures for 9 days prior to ovulation at times corresponding to days 8-17 of the cycle in 2006, and days 6-14 in 2007 and 2008. The proportion of ewes producing multiple ovulations was higher (P<0.05) in the lucerne and chicory (0.36, 0.38) than the phalaris (0.27), and intermediate in the lupin (0.33) treatment. Regression analysis showed that the proportion of ewes with multiple ovulations increased with the quantity of live herbage (P<0.04). Responses were achieved even at low levels of live herbage with 90% of the maximum proportion of multiples occurring at 350kg DM/ha. It is concluded that providing short-term grazing of live chicory or lucerne to ewes can increase ovulation rates relative to ewes grazing senesced phalaris and to levels similar to those achieved by lupin grain supplementation.


Asunto(s)
Cichorium intybus , Dieta , Sincronización del Estro , Medicago sativa , Ovulación/fisiología , Ovinos/fisiología , Animales , Composición Corporal , Peso Corporal , Femenino , Estaciones del Año
10.
Parasitology ; 136(9): 953-66, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19549353

RESUMEN

Cryptosporidium parvum are protozoan parasites responsible for outbreaks of gastrointestinal disease worldwide. Within the apical complex of this organism reside numerous vesicular secretory organelles and their discharge has been identified as essential for sporozoite motility, cell attachment and penetration. Traditionally, investigation of apical organelle discharge has relied on microscopic and immunochemical hybridization techniques. In this study we demonstrate for the first time how flow cytometry, in combination with vital dye staining, provides an avenue for discrimination of distinct physiological events occurring within Cryptosporidium sporozoites post-excystation. Time-course studies of freshly excysted sporozoites were carried out at 37 degrees C in cell-free medium, stained with the fluorescent dyes SYTO9/PI, DiBAC4(3), Fluo-4 AM or FM1-43 and analysed by flow cytometry. Significant decreases in sporozoite plasma membrane permeability and increased membrane depolarization were found to be accompanied by concomitant increases in intracellular calcium. Subsequent to these changes, large increases in exocytosed vesicular membrane were apparent. In addition, by measuring side and forward angle light scatter we were able to assess changes in internal granularity and size of sporozoites post-excystation. These observations were suggestive of rapid mobilization, utilization and discharge of apical organelles within sporozoites, which we relate to changes in sporozoite infectivity, ATP levels and total secreted soluble protein.


Asunto(s)
Cryptosporidium parvum/citología , Cryptosporidium parvum/fisiología , Citometría de Flujo , Esporozoítos/fisiología , Animales , Coloración y Etiquetado
11.
J Appl Microbiol ; 104(5): 1311-23, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18248370

RESUMEN

AIMS: To determine the effect of solar radiation on Cryptosporidium parvum in tap and environmental waters. METHODS AND RESULTS: Outdoor tank experiments and a cell culture infectivity assay were used to measure solar inactivation of C. parvum oocysts in different waters. Experiments conducted on days with different levels of solar insolation identified rapid inactivation of oocysts in tap water (up to 90% inactivation within the first hour). Increased dissolved organic carbon content in environmental waters decreased solar inactivation. The role of solar ultraviolet (UV) in inactivation was confirmed by long-pass filter experiments, where UV-B was identified as the most germicidal wavelength. Reductions in oocyst infectivity following solar radiation were not related to a loss of excystation capacity. CONCLUSIONS: Solar UV can rapidly inactivate C. parvum in environmental waters. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study to assess natural sunlight inactivation of C. parvum oocysts in surface waters and drinking water using an infectivity measure and determines the wavelengths of light responsible for the inactivation. The findings presented here provide valuable information for determining the relative risks associated with Cryptosporidium oocysts in aquatic environments and identify solar radiation as a critical process affecting the oocyst survival in the environment.


Asunto(s)
Cryptosporidium parvum/efectos de la radiación , Microbiología del Agua , Purificación del Agua/métodos , Animales , Agua Dulce , Oocistos/fisiología , Oocistos/efectos de la radiación , Rayos Ultravioleta , Abastecimiento de Agua
12.
Parasitology ; 134(Pt 3): 309-23, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17096874

RESUMEN

Cryptosporidium are parasitic protozoans that cause gastrointestinal disease and represent a significant risk to public health. Cryptosporidium oocysts are prevalent in surface waters as a result of human, livestock and native animal faecal contamination. The resistance of oocysts to the concentrations of chlorine and monochloramine used to disinfect potable water increases the risk of waterborne transmission via drinking water. In addition to being resistant to commonly used disinfectants, it is thought that oocysts can persist in the environment and be readily mobilized by precipitation events. This paper will review the critical processes involved in the inactivation or removal of oocysts in the terrestrial and aquatic environments and consider how these processes will respond in the context of climate change.


Asunto(s)
Clima , Cryptosporidium/crecimiento & desarrollo , Oocistos/crecimiento & desarrollo , Suelo/parasitología , Agua/parasitología , Animales , Cryptosporidium/efectos de los fármacos , Desinfectantes/farmacología , Humanos , Ratones , Ratones Endogámicos BALB C , Oocistos/efectos de los fármacos , Suelo/análisis , Temperatura
13.
Phys Rev Lett ; 87(25): 251802, 2001 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-11736561

RESUMEN

We report on the extraction of R = sigma(L)/sigma(T) from CCFR nu(mu)-Fe and nu(mu)-Fe differential cross sections. The CCFR differential cross sections do not show the deviations from the QCD expectations that are seen in the CDHSW data at very low and very high x. R as measured in nu(mu) scattering is in agreement with R as measured in muon and electron scattering. All data on R for Q(2)>1 GeV(2) are in agreement with a NNLO QCD calculation which uses NNLO parton distribution functions and includes target mass effects. We report on the first measurements of R in the low x and Q(2)<1 GeV(2) region (where an anomalous large rise in R for nuclear targets has been observed by the HERMES Collaboration).

14.
Phys Rev Lett ; 86(24): 5430-3, 2001 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-11415268

RESUMEN

A new structure function analysis of CCFR deep inelastic nu-N and nu-N scattering data is presented for previously unexplored kinematic regions down to Bjorken x = 0.0045 and Q(2) = 0.3 GeV(2). Comparisons to charged lepton scattering data from NMC and E665 experiments are made and the behavior of the structure function F(2)(nu)2 is studied in the limit Q(2)-->0.

15.
Phys Rev Lett ; 86(13): 2742-5, 2001 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-11290028

RESUMEN

We report on the extraction of the structure functions F2 and DeltaxF(3) = xF(nu)(3)-xF(nu;)(3) from CCFR nu(mu)-Fe and nu;(mu)-Fe differential cross sections. The extraction is performed in a physics model-independent (PMI) way. This first measurement of DeltaxF(3), which is useful in testing models of heavy charm production, is higher than current theoretical predictions. The ratio of the F2 (PMI) values measured in nu(mu) and mu scattering is in agreement (within 5%) with the predictions of next-to-leading-order parton distribution functions using massive charm production schemes, thus resolving the long-standing discrepancy between the two sets of data.

16.
Int J Clin Exp Hypn ; 49(1): 30-7, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11190790

RESUMEN

Hypnotic responsiveness may depend upon the ability to inhibit the irrelevant stimuli that evoke responses that are incompatible with current goals (or the mapping between an irrelevant/disruptive stimulus and its response) in order to actively maintain task-relevant information. In a simple correlation design, the authors investigated the relationship between cognitive inhibition (negative priming) and hypnotic responsiveness. A statistically significant correlation was obtained between the extent of negative priming (measured in time latency) and hypnotic responsiveness (r = .491). Limitations of this preliminary study and implications for future work are discussed.


Asunto(s)
Atención , Hipnosis , Inhibición Psicológica , Adulto , Femenino , Humanos , Masculino , Recuerdo Mental , Inventario de Personalidad , Sugestión , Aprendizaje Verbal
17.
J Am Optom Assoc ; 70(8): 515-24, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10506815

RESUMEN

BACKGROUND: Limitations of the surgical correction for myopia include inaccuracy, instability, treatment of the central optical zone, and lack of reversibility. KeraVision Intacs offer an alternative that addresses these shortcomings. METHODS: We present 1 year of follow-up information on 95 subjects enrolled in the United States Food and Drug Administration Phase III clinical trials. RESULTS: At 1 year, 99% of patients (89 of 90) had 20/40 uncorrected vision or better. Ninety-two percent of eyes (83 of 90) were within 1.00 D of intended correction and 76% of eyes (68 of 90) were within 0.50 D of intended correction. Stability was achieved at 3 months, with 96% of subjects (86 of 90) having less than 1.00 D of change from their previous examination. In a substudy, 89% eyes (58 of 65) varied within +/- 0.50 D over the course of a day. Corneal curvature changed as predicted, resulting in a prolate aspheric shape within the central optical zone. Most complications or adverse events experienced were managed with additional medication or surgical intervention, resulting in a favorable outcome for subjects. CONCLUSIONS: KeraVision Intacs are effective, predictable, stable, and safe. This additive technique may also offer reversibility.


Asunto(s)
Miopía/cirugía , Prótesis e Implantes , Implantación de Prótesis , Adulto , Diseño de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prótesis e Implantes/efectos adversos , Resultado del Tratamiento
18.
Int J Clin Exp Hypn ; 46(3): 295-313, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9650441

RESUMEN

Two studies were completed to test whether responding to hypnotic suggestions requires intentional effort. Hypnotic suggestions for amnesia were used as an analog of thought suppression, and Wegner's model of ironic processing was applied to hypnotic responding. In the first study, participants were required to maintain suggested amnesia while performing a cancellation task with and without a cognitive load. The second study required suppression of thoughts of a favorite car, once with "blank-mind" instructions and then with a suggestion for amnesia. The results of these studies indicate that dissociated control theory provides the best explanation for hypnotic responding in one subset of highly hypnotizable participants, whereas more intentional responding provides the best explanation for others.


Asunto(s)
Trastornos Disociativos/fisiopatología , Hipnosis , Memoria/fisiología , Volición/fisiología , Adulto , Análisis de Varianza , Femenino , Humanos , Masculino
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