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1.
Health Phys ; 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38888447

RESUMEN

ABSTRACT: At the University of Alabama at Birmingham (UAB), many diagnostic and therapeutic procedures involving radioactive materials or radiation-producing machines are performed daily. A growing number of minor but preventable incidents related to radiation safety have brought up concerns related to the effectiveness of the training program. A comprehensive literature review was performed to summarize post-COVID insights into andragogic online training practices, statistical analyses, and overall retention competencies in radiation safety. Andragogic research shows that the best method of training adult learners is controlled simulation that tests critical thinking and problem-solving capabilities, drawing upon previous knowledge or experiences. A new training curriculum based on these andragogic principles was designed and administered to a subgroup of UAB radiation workers. Scores from pre-testing and post-testing were collected and analyzed. An ANCOVA was used to account for differences in the pre-test scores between the control and experimental groups, which was found to be statistically significant (p = 0.018), suggesting that small changes in a radiation safety training program can have significant impacts in retention of key information.

2.
Behav Brain Sci ; 45: e212, 2022 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-36172784

RESUMEN

We question the free energy principle (FEP) as it is used in contemporary physics. If the FEP is incorrect in physics, then it cannot ground the authors' arguments. We also question the assumption that perception requires inference. We argue that perception (including perception of social affordances) can be direct, in which case inference is not required.

3.
Arch Biochem Biophys ; 726: 109248, 2022 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-35667910

RESUMEN

A photo-induced cyclic peroxidation in isolated chloroplasts is described. In an osmotic buffered medium, chloroplasts upon illumination produce malondialdehyde (MDA)-a decomposition product of tri-unsaturated fatty acid hydroperoxides-bleach endogenous chlorophyll, and consume oxygen. These processes show (a) no reaction in the absence of illumination; (b) an initial lag phase upon illumination of 10-20 minutes duration; (c) a linear phase in which the rate is proportional to the square root of the light intensity; (d) cessation of reaction occurring within 3 minutes after illumination ceases; and (e) a termination phase after several hours of illumination. The kinetics of the above processes fit a cyclic peroxidation equation with velocity coefficients near those for chemical peroxidation. The stoichiometry of MDA/O2 = 0.02, and O2/Chlbleached = 6.9 correlates well with MDA production efficiency in other biological systems and with the molar ratio of unsaturated fatty acids to chlorophyll. The energies of activation for the lag and linear phases are 17 and 0 kcal/mole, respectively, the same as that for autoxidation. During the linear phase of oxygen uptake the dependence upon temperature and O2 concentration indicates that during the reaction, oxygen tension at the site of peroxidation is 100-fold lower than in the aqueous phase. It is concluded that isolated chloroplasts upon illumination can undergo a cyclic peroxidation initiated by the light absorbed by chlorophyll. Photoperoxidation results in a destruction of the chlorophyll and tri-unsaturated fatty acids of the chloroplast membranes.


Asunto(s)
Cloroplastos , Ácidos Grasos , Clorofila , Ácidos Grasos Insaturados , Cinética , Luz , Oxígeno
5.
Risk Anal ; 38(2): 333-344, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28616889

RESUMEN

Studies are continuously performed to improve risk communication campaign designs to better prepare residents to act in the safest manner during an emergency. To that end, this article investigates the predictive ability of the protective action decision model (PADM), which links environmental and social cues, predecision processes (attention, exposure, and comprehension), and risk decision perceptions (threat, alternative protective actions, and stakeholder norms) with protective action decision making. This current quasi-longitudinal study of residents (N = 400 for each year) in a high-risk (chemical release) petrochemical manufacturing community investigated whether PADM core risk perceptions predict protective action decision making. Telephone survey data collected at four intervals (1995, 1998, 2002, 2012) reveal that perceptions of protective actions and stakeholder norms, but not of threat, currently predict protective action decision making (intention to shelter in place). Of significance, rather than threat perceptions, perception of Wally Wise Guy (a spokes-character who advocates shelter in place) correlates with perceptions of protective action, stakeholder norms, and protective action decision making. Wally's response-efficacy advice predicts residents' behavioral intentions to shelter in place, thereby offering contextually sensitive support and refinement for PADM.

6.
Cell Rep ; 17(9): 2183-2194, 2016 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-27880896

RESUMEN

Xenophagy is a form of selective autophagy that involves the targeting and elimination of intracellular pathogens through several recognition, recruitment, and ubiquitination events. E3 ubiquitin ligases control substrate selectivity in the ubiquitination cascade; however, systematic approaches to map the role of E3 ligases in antibacterial autophagy have been lacking. We screened more than 600 putative human E3 ligases, identifying E3 ligases that are required for adaptor protein recruitment and LC3-bacteria colocalization, critical steps in antibacterial autophagy. An unbiased informatics approach pinpointed RNF166 as a key gene that interacts with the autophagy network and controls the recruitment of ubiquitin as well as the autophagy adaptors p62 and NDP52 to bacteria. Mechanistic studies demonstrated that RNF166 catalyzes K29- and K33-linked polyubiquitination of p62 at residues K91 and K189. Thus, our study expands the catalog of E3 ligases that mediate antibacterial autophagy and identifies a critical role for RNF166 in this process.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Antibacterianos/farmacología , Autofagia/efectos de los fármacos , Ubiquitina-Proteína Ligasas/metabolismo , Células HEK293 , Células HeLa , Humanos , Listeria/efectos de los fármacos , Listeria/crecimiento & desarrollo , Lisina/metabolismo , Unión Proteica , ARN Interferente Pequeño/metabolismo , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/crecimiento & desarrollo , Salmonella typhimurium/metabolismo , Proteína Sequestosoma-1/metabolismo , Ubiquitinación
7.
Opt Express ; 24(13): 13931-8, 2016 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-27410555

RESUMEN

We present low temperature nano-optical characterization of a silicon-on-insulator (SOI) waveguide integrated SNSPD. The SNSPD is fabricated from an amorphous Mo83Si17 thin film chosen to give excellent substrate conformity. At 350 mK, the SNSPD exhibits a uniform photoresponse under perpendicular illumination, corresponding to a maximum system detection efficiency of approximately 5% at 1550 nm wavelength. Under these conditions 10 Hz dark count rate and 51 ps full width at half maximum (FWHM) timing jitter is observed.

8.
Risk Anal ; 36(6): 1108-24, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26503696

RESUMEN

Calls for emergency right-to-know in the 1980s, and, in the 1990s, risk management planning, motivated U.S. chemical manufacturing and refining industries to operationalize a three-pronged approach to risk minimization and communication: reflective management to increase legitimacy, operational safety programs to raise trust, and community engagement designed to facilitate citizens' emergency response efficacy. To assess these management, operational, and communication initiatives, communities (often through Local Emergency Planning Committees) monitored the impact of such programs. In 2012, the fourth phase of a quasi-longitudinal study was conducted to assess the effectiveness of operational change and community outreach in one bellwether community. This study focuses on legitimacy, trust, and response efficacy to suggest that an industry can earn legitimacy credits by raising its safety and environmental impact standards, by building trust via that change, and by communicating emergency response messages to near residents to raise their response efficacy. As part of its campaign to demonstrate its concern for community safety through research, planning, and implementation of safe operations and viable emergency response systems, this industry uses a simple narrative of risk/emergency response-shelter-in-place-communicated by a spokes-character: Wally Wise Guy.

9.
Immunity ; 43(4): 715-26, 2015 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-26488816

RESUMEN

CARD9 is a central component of anti-fungal innate immune signaling via C-type lectin receptors, and several immune-related disorders are associated with CARD9 alterations. Here, we used a rare CARD9 variant that confers protection against inflammatory bowel disease as an entry point to investigating CARD9 regulation. We showed that the protective variant of CARD9, which is C-terminally truncated, acted in a dominant-negative manner for CARD9-mediated cytokine production, indicating an important role for the C terminus in CARD9 signaling. We identified TRIM62 as a CARD9 binding partner and showed that TRIM62 facilitated K27-linked poly-ubiquitination of CARD9. We identified K125 as the ubiquitinated residue on CARD9 and demonstrated that this ubiquitination was essential for CARD9 activity. Furthermore, we showed that similar to Card9-deficient mice, Trim62-deficient mice had increased susceptibility to fungal infection. In this study, we utilized a rare protective allele to uncover a TRIM62-mediated mechanism for regulation of CARD9 activation.


Asunto(s)
Proteínas Adaptadoras de Señalización CARD/fisiología , Candidiasis Invasiva/inmunología , Receptores de Angiotensina/fisiología , Receptores de Endotelina/fisiología , Ubiquitina-Proteína Ligasas/fisiología , Adyuvantes Inmunológicos/farmacología , Animales , Proteínas Adaptadoras de Señalización CARD/química , Proteínas Adaptadoras de Señalización CARD/deficiencia , Proteínas Adaptadoras de Señalización CARD/genética , Candidiasis Invasiva/genética , Colitis/inducido químicamente , Colitis/genética , Colitis/prevención & control , Citocinas/biosíntesis , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Genes Dominantes , Predisposición Genética a la Enfermedad , Células HEK293 , Células HeLa , Humanos , Enfermedades Inflamatorias del Intestino/genética , Ratones , Ratones de la Cepa 129 , Ratones Noqueados , Mapeo de Interacción de Proteínas , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/fisiología , Procesamiento Proteico-Postraduccional , Estructura Terciaria de Proteína , Receptores de Angiotensina/química , Receptores de Angiotensina/deficiencia , Receptores de Endotelina/química , Receptores de Endotelina/deficiencia , Proteínas Recombinantes de Fusión/metabolismo , Transducción de Señal , Organismos Libres de Patógenos Específicos , Proteínas de Motivos Tripartitos , Ubiquitina-Proteína Ligasas/química , Ubiquitinación
10.
Cell Rep ; 11(12): 1905-18, 2015 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-26095365

RESUMEN

The polymorphism ATG16L1 T300A, associated with increased risk of Crohn's disease, impairs pathogen defense mechanisms including selective autophagy, but specific pathway interactions altered by the risk allele remain unknown. Here, we use perturbational profiling of human peripheral blood cells to reveal that CLEC12A is regulated in an ATG16L1-T300A-dependent manner. Antibacterial autophagy is impaired in CLEC12A-deficient cells, and this effect is exacerbated in the presence of the ATG16L1(∗)300A risk allele. Clec12a(-/-) mice are more susceptible to Salmonella infection, supporting a role for CLEC12A in antibacterial defense pathways in vivo. CLEC12A is recruited to sites of bacterial entry, bacteria-autophagosome complexes, and sites of sterile membrane damage. Integrated genomics identified a functional interaction between CLEC12A and an E3-ubiquitin ligase complex that functions in antibacterial autophagy. These data identify CLEC12A as early adaptor molecule for antibacterial autophagy and highlight perturbational profiling as a method to elucidate defense pathways in complex genetic disease.


Asunto(s)
Proteínas Portadoras/genética , Enfermedad de Crohn/genética , Lectinas Tipo C/genética , Receptores Mitogénicos/genética , Infecciones por Salmonella/genética , Alelos , Animales , Autofagia/genética , Proteínas Relacionadas con la Autofagia , Enfermedad de Crohn/microbiología , Enfermedad de Crohn/patología , Predisposición Genética a la Enfermedad , Genómica , Humanos , Lectinas Tipo C/biosíntesis , Ratones , Receptores Mitogénicos/biosíntesis , Factores de Riesgo , Salmonella/patogenicidad , Infecciones por Salmonella/microbiología
11.
Nano Lett ; 15(2): 819-22, 2015 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-25575021

RESUMEN

Superconducting nanowire single photon detectors are rapidly emerging as a key infrared photon-counting technology. Two front-side-coupled silver dipole nanoantennas, simulated to have resonances at 1480 and 1525 nm, were fabricated in a two-step process. An enhancement of 50 to 130% in the system detection efficiency was observed when illuminating the antennas. This offers a pathway to increasing absorption into superconducting nanowires, creating larger active areas, and achieving more efficient detection at longer wavelengths.

12.
BMC Public Health ; 14: 432, 2014 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-24885426

RESUMEN

BACKGROUND: Although there is some evidence to support an association between exposure to televised tobacco control campaigns and recall among youth, little research has been conducted among adults. In addition, no previous work has directly compared the impact of different types of emotive campaign content. The present study examined the impact of increased exposure to tobacco control advertising with different types of emotive content on rates and durations of self-reported recall. METHODS: Data on recall of televised campaigns from 1,968 adult smokers residing in England through four waves of the International Tobacco Control (ITC) United Kingdom Survey from 2005 to 2009 were merged with estimates of per capita exposure to government-run televised tobacco control advertising (measured in GRPs, or Gross Rating Points), which were categorised as either "positive" or "negative" according to their emotional content. RESULTS: Increased overall campaign exposure was found to significantly increase probability of recall. For every additional 1,000 GRPs of per capita exposure to negative emotive campaigns in the six months prior to survey, there was a 41% increase in likelihood of recall (OR = 1.41, 95% CI: 1.24-1.61), while positive campaigns had no significant effect. Increased exposure to negative campaigns in both the 1-3 months and 4-6 month periods before survey was positively associated with recall. CONCLUSIONS: Increased per capita exposure to negative emotive campaigns had a greater effect on campaign recall than positive campaigns, and was positively associated with increased recall even when the exposure had occurred more than three months previously.


Asunto(s)
Publicidad/métodos , Publicidad/estadística & datos numéricos , Recuerdo Mental , Cese del Hábito de Fumar/métodos , Prevención del Hábito de Fumar , Televisión/estadística & datos numéricos , Adolescente , Adulto , Distribución por Edad , Recolección de Datos/métodos , Recolección de Datos/estadística & datos numéricos , Emociones , Inglaterra , Femenino , Política de Salud , Promoción de la Salud/métodos , Promoción de la Salud/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Cese del Hábito de Fumar/estadística & datos numéricos , Reino Unido , Adulto Joven
13.
Proc Natl Acad Sci U S A ; 111(21): 7741-6, 2014 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-24821797

RESUMEN

A coding polymorphism (Thr300Ala) in the essential autophagy gene, autophagy related 16-like 1 (ATG16L1), confers increased risk for the development of Crohn disease, although the mechanisms by which single disease-associated polymorphisms contribute to pathogenesis have been difficult to dissect given that environmental factors likely influence disease initiation in these patients. Here we introduce a knock-in mouse model expressing the Atg16L1 T300A variant. Consistent with the human polymorphism, T300A knock-in mice do not develop spontaneous intestinal inflammation, but exhibit morphological defects in Paneth and goblet cells. Selective autophagy is reduced in multiple cell types from T300A knock-in mice compared with WT mice. The T300A polymorphism significantly increases caspase 3- and caspase 7-mediated cleavage of Atg16L1, resulting in lower levels of full-length Atg16Ll T300A protein. Moreover, Atg16L1 T300A is associated with decreased antibacterial autophagy and increased IL-1ß production in primary cells and in vivo. Quantitative proteomics for protein interactors of ATG16L1 identified previously unknown nonoverlapping sets of proteins involved in ATG16L1-dependent antibacterial autophagy or IL-1ß production. These findings demonstrate how the T300A polymorphism leads to cell type- and pathway-specific disruptions of selective autophagy and suggest a mechanism by which this polymorphism contributes to disease.


Asunto(s)
Proteínas Portadoras/genética , Enfermedad de Crohn/inmunología , Células de Paneth/patología , Polimorfismo de Nucleótido Simple/genética , Infecciones por Salmonella/inmunología , Animales , Autofagia/genética , Proteínas Relacionadas con la Autofagia , Western Blotting , Cromatografía Liquida , Enfermedad de Crohn/genética , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Técnicas de Sustitución del Gen , Células Caliciformes/patología , Ratones , Proteómica , Reacción en Cadena en Tiempo Real de la Polimerasa , Espectrometría de Masas en Tándem
14.
IEEE Trans Image Process ; 23(5): 2206-21, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24723577

RESUMEN

Newly developed hypertext transfer protocol (HTTP)-based video streaming technologies enable flexible rate-adaptation under varying channel conditions. Accurately predicting the users' quality of experience (QoE) for rate-adaptive HTTP video streams is thus critical to achieve efficiency. An important aspect of understanding and modeling QoE is predicting the up-to-the-moment subjective quality of a video as it is played, which is difficult due to hysteresis effects and nonlinearities in human behavioral responses. This paper presents a Hammerstein-Wiener model for predicting the time-varying subjective quality (TVSQ) of rate-adaptive videos. To collect data for model parameterization and validation, a database of longer duration videos with time-varying distortions was built and the TVSQs of the videos were measured in a large-scale subjective study. The proposed method is able to reliably predict the TVSQ of rate adaptive videos. Since the Hammerstein-Wiener model has a very simple structure, the proposed method is suitable for online TVSQ prediction in HTTP-based streaming.

15.
PLoS One ; 8(9): e73601, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24039994

RESUMEN

Chemical analyses were conducted to determine the qualitative and quantitative differences in monoterpenes and sesquiterpenes in plant material from avocado trees, Persea americana Mill. (Lauraceae). The initial study analyzed plant material sampled from the trunk to the leaves through different branch diameters to quantify proximo-distal spatial differences within a tree. All trees were seedlings initiated from a single maternal tree. Two-way analysis of variance was conducted on 34 chemicals that comprised at least 3% of the total chemical content of at least one tree and/or location within a tree. There were significant interactions between genotype and location sampled for most chemicals. Parentage analysis using microsatellite molecular markers (SSR's) determined that the four trees had three fathers and that they represented two full-siblings and two half-sibling trees. Descriptive discriminant analysis found that both genotype and location within a tree could be separated based on chemical content, and that the chemical content from full-siblings tended to be more similar than chemical content from half-siblings. To further explore the relationship between genetic background and chemical content, samples were analyzed from leaf material from 20 trees that included two sets of full-sibling seedling trees, the maternal tree and the surviving paternal tree. Descriptive discriminant analysis found good separation between the two full-sibling groups, and that the separation was associated with chemistry of the parental trees. Six groups of chemicals were identified that explained the variation among the trees. We discuss the results in relation to the discrimination process used by wood-boring insects for site-selection on host trees, for tree selection among potential host trees, and the potential use of terpenoid chemical content in chemotaxonomy of avocado trees.


Asunto(s)
Repeticiones de Microsatélite/genética , Persea/química , Persea/genética , Terpenos/análisis , Análisis Discriminante , Cromatografía de Gases y Espectrometría de Masas , Genotipo , Hojas de la Planta/química , Hojas de la Planta/genética , Polen/química , Polen/genética , Reacción en Cadena de la Polimerasa , Plantones/química , Plantones/genética , Terpenos/química
16.
PLoS One ; 8(4): e61890, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23637924

RESUMEN

Cyanobacterial harmful blooms (CyanoHABs) that produce microcystins are appearing in an increasing number of freshwater ecosystems worldwide, damaging quality of water for use by human and aquatic life. Heterotrophic bacteria assemblages are thought to be important in transforming and detoxifying microcystins in natural environments. However, little is known about their taxonomic composition or pathways involved in the process. To address this knowledge gap, we compared the metagenomes of Lake Erie free-living bacterioplankton assemblages in laboratory microcosms amended with microcystins relative to unamended controls. A diverse array of bacterial phyla were responsive to elevated supply of microcystins, including Acidobacteria, Actinobacteria, Bacteroidetes, Planctomycetes, Proteobacteria of the alpha, beta, gamma, delta and epsilon subdivisions and Verrucomicrobia. At more detailed taxonomic levels, Methylophilales (mainly in genus Methylotenera) and Burkholderiales (mainly in genera Bordetella, Burkholderia, Cupriavidus, Polaromonas, Ralstonia, Polynucleobacter and Variovorax) of Betaproteobacteria were suggested to be more important in microcystin degradation than Sphingomonadales of Alphaproteobacteria. The latter taxa were previously thought to be major microcystin degraders. Homologs to known microcystin-degrading genes (mlr) were not overrepresented in microcystin-amended metagenomes, indicating that Lake Erie bacterioplankton might employ alternative genes and/or pathways in microcystin degradation. Genes for xenobiotic metabolism were overrepresented in microcystin-amended microcosms, suggesting they are important in bacterial degradation of microcystin, a phenomenon that has been identified previously only in eukaryotic systems.


Asunto(s)
Cianobacterias/genética , Cianobacterias/metabolismo , Redes y Vías Metabólicas , Metagenómica , Microcistinas/metabolismo , Microbiología del Agua , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Cianobacterias/clasificación , Cianobacterias/crecimiento & desarrollo , Lagos , Anotación de Secuencia Molecular , Filogenia , ARN Ribosómico 16S/genética
17.
Cell Host Microbe ; 12(6): 778-90, 2012 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-23245322

RESUMEN

Several species of pathogenic bacteria replicate within an intracellular vacuolar niche. Bacteria that escape into the cytosol are captured by the autophagic pathway and targeted for lysosomal degradation, representing a defense against bacterial exploitation of the host cytosol. Autophagic capture of Salmonella Typhimurium occurs predominantly via generation of a polyubiquitin signal around cytosolic bacteria, binding of adaptor proteins, and recruitment of autophagic machinery. However, the components mediating bacterial target selection and ubiquitination remain obscure. We identify LRSAM1 as the E3 ligase responsible for anti-Salmonella autophagy-associated ubiquitination. LRSAM1 localizes to several intracellular bacterial pathogens and generates the bacteria-associated ubiquitin signal; these functions require LRSAM1's leucine-rich repeat and RING domains, respectively. Using cells from LRSAM1-deficient individuals, we confirm that LRSAM1 is required for ubiquitination associated with intracellular bacteria but dispensable for ubiquitination of aggregated proteins. LRSAM1 is therefore a bacterial recognition protein and ubiquitin ligase that defends the cytoplasm from invasive pathogens.


Asunto(s)
Autofagia , Salmonella typhimurium/inmunología , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina/metabolismo , Técnicas de Inactivación de Genes , Células HeLa , Humanos , Estructura Terciaria de Proteína , Ubiquitina-Proteína Ligasas/genética
18.
J Econ Entomol ; 105(2): 471-9, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22606817

RESUMEN

Tests were conducted that evaluated efficacy of wax matrix bait stations for Ceratitis capitata (Wiedemann) adults in Guatemala. Bait stations were exposed to outdoor conditions to determine effect of weathering on longevity as indicated by bait station age. Results of laboratory tests found that bait stations with spinosad and ammonium acetate remained effective for at least 31 d compared with pesticide-free controls, although there was some loss of efficacy over time. Percentage mortality for bait station strips with 2% spinosad and 1% ammonium acetate decreased from 100 +/- 0.0% on day 0 to 70 +/- 7.1% after 31 d. Ammonia concentration had little effect on percentage mortality although there was some indication that ammonia concentration affected number of flies observed on the bait stations. Bait station strips (one per cage) were more effective than controls for 6-8 wk when tests were conducted in field cages (3 m diameter x 2 m), but only 2-3 wk when tests were conducted in large (2.5 m high and 6.0 m wide and 7.5 m long) field cages. Longevity was restored when multiple bait stations (3, 6, or 12) were deployed per cage. Bait stations containing methomyl were used for field tests of efficacy for wild flies. Dipped lure bait stations, which were made by coating two edges of commercial ammonium acetate and trimethylamine lures, killed six times more flies than corn cob bait stations dipped into a Nulure/malathion solution. They also killed more flies than pesticide-free controls for 8 wk.


Asunto(s)
Ceratitis capitata/efectos de los fármacos , Control de Insectos/métodos , Insecticidas/farmacología , Feromonas/farmacología , Acetatos/farmacología , Animales , Bicarbonatos/farmacología , Relación Dosis-Respuesta a Droga , Combinación de Medicamentos , Femenino , Guatemala , Control de Insectos/instrumentación , Macrólidos/farmacología , Masculino , Metomil/farmacología , Metilaminas/farmacología , Factores de Tiempo , Ceras/química
19.
J Econ Entomol ; 105(2): 659-69, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22606839

RESUMEN

Redbay ambrosia beetle, Xyleborus glabratus Eichhoff, is an exotic wood-borer that vectors the fungal agent (Raffaelea lauricola) responsible for laurel wilt. Laurel wilt has had severe impact on forest ecosystems in the southeastern United States, killing a large proportion of native Persea trees, particularly redbay (P. borbonia) and swampbay (P. palustris), and currently poses an economic threat to avocado (P. americana) in Florida. To control the spread of this lethal disease, effective attractants are needed for early detection of the vector. Two 12-wk field tests were conducted in Florida to evaluate efficacy and longevity of manuka and phoebe oil lures, and to relate captures of X. glabratus to release rates of putative sesquiterpene attractants. Two trap types were also evaluated, Lindgren funnel traps and sticky panel traps. To document lure emissions over time, a separate set of lures was aged outdoors for 12 wk and sampled periodically to quantify volatile sesquiterpenes using super-Q adsorbant and gas chromatography-mass spectroscopy analysis. Phoebe lures captured significantly more X. glabratus than manuka lures, and sticky traps captured more beetles than funnel traps. Phoebe lures captured X. glabratus for 10-12 wk, but field life of manuka lures was 2-3 wk. Emissions of alpha-copaene, alpha-humulene, and cadinene were consistently higher from phoebe lures, particularly during the 2-3 wk window when manuka lures lost efficacy, suggesting that these sesquiterpenes are primary kairomones used by host-seeking females. Results indicate that the current monitoring system is suboptimal for early detection of X. glabratus because of rapid depletion of sesquiterpenes from manuka lures.


Asunto(s)
Control de Insectos/métodos , Leptospermum/química , Aceites Volátiles/farmacología , Feromonas/farmacología , Sesquiterpenos/farmacología , Terpenos/farmacología , Gorgojos/efectos de los fármacos , Animales , Femenino , Florida , Aceites Volátiles/análisis , Sesquiterpenos/análisis , Terpenos/análisis , Factores de Tiempo
20.
Radiol Technol ; 83(1): 20-8, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21908777

RESUMEN

PURPOSE: To investigate the effect of varying source-to-image distance (SID) on image quality and radiation dose using direct digital radiography (DR). METHODS: An anthropomorphic pelvic phantom was positioned for a standard anteroposterior DR examination. The SID was initially set at 100 cm, and the tube potential remained constant at 80 kVp. Two exposures were taken at this SID, and the entrance surface dose (ESD) and effective dose (ED) were calculated. Images were sent to a reporting-grade picture archiving and communication system workstation for image quality analysis. The SID was then varied by 10-cm intervals, up to its maximum (80 cm to 147 cm), with 2 exposures taken for each interval. Grid usage also was varied to determine its effect on radiation dose and image quality. Image quality was assessed by 4 observers (2 images per SID interval) who were blinded to the measurements, using a rating system adapted from the European Guidelines on Quality Criteria for Diagnostic Radiographic Images. RESULTS: Increasing SID results in lower ESD and ED compared with the standard 100-cm SID (147 cm: 2.56 mGy and 0.44 mSv, respectively, vs 100 cm: 3.00 mGy and 0.51 mSv, respectively; P<.05). Reduction of the SID resulted in an increased ESD and ED (80 cm: 3.79 mGy and 0.65 mSv, respectively; P<.05). Analysis of the resultant images demonstrated a statistically nonsignificant minor increase in image quality when increasing SID (P=.276). Image quality for 60 cm, 80 cm, 100 cm, 120 cm, 140 cm, and 147 cm was given a mean score of 17.5, 30, 31, 33, 33, and 32, respectively. Removal of the grid resulted in lower image quality but a significantly lower overall ESD and ED. CONCLUSION: Significant reductions in ESD and ED can be achieved, without loss of image quality, with a larger-than-normal SID for AP pelvic DR examinations.


Asunto(s)
Pelvis/diagnóstico por imagen , Dosis de Radiación , Intensificación de Imagen Radiográfica , Tecnología Radiológica/métodos , Humanos , Fantasmas de Imagen
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