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1.
Precis Agric ; : 1-23, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-37363791

RESUMO

Even though mechanization has dramatically decreased labor requirements, vineyard management costs are still affected by selective operations such as winter pruning. Robotic solutions are becoming more common in agriculture, however, few studies have focused on grapevines. This work aims at fine-tuning and testing two different deep neural networks for: (i) detecting pruning regions (PRs), and (ii) performing organ segmentation of spur-pruned dormant grapevines. The Faster R-CNN network was fine-tuned using 1215 RGB images collected in different vineyards and annotated through bounding boxes. The network was tested on 232 RGB images, PRs were categorized by wood type (W), orientation (Or) and visibility (V), and performance metrics were calculated. PR detection was dramatically affected by visibility. Highest detection was associated with visible intermediate complex spurs in Merlot (0.97), while most represented coplanar simple spurs allowed a 74% detection rate. The Mask R-CNN network was trained for grapevine organs (GOs) segmentation by using 119 RGB images annotated by distinguishing 5 classes (cordon, arm, spur, cane and node). The network was tested on 60 RGB images of light pruned (LP), shoot-thinned (ST) and unthinned control (C) grapevines. Nodes were the best segmented GOs (0.88) and general recall was higher for ST (0.85) compared to C (0.80) confirming the role of canopy management in improving performances of hi-tech solutions based on artificial intelligence. The two fine-tuned and tested networks are part of a larger control framework that is under development for autonomous winter pruning of grapevines. Supplementary Information: The online version contains supplementary material available at 10.1007/s11119-023-10006-y.

2.
Phys Rev Lett ; 120(6): 061802, 2018 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-29481237

RESUMO

We report the result of a blinded search for weakly interacting massive particles (WIMPs) using the majority of the SuperCDMS Soudan data set. With an exposure of 1690 kg d, a single candidate event is observed, consistent with expected backgrounds. This analysis (combined with previous Ge results) sets an upper limit on the spin-independent WIMP-nucleon cross section of 1.4×10^{-44} (1.0×10^{-44}) cm^{2} at 46 GeV/c^{2}. These results set the strongest limits for WIMP-germanium-nucleus interactions for masses >12 GeV/c^{2}.

3.
Osteoarthritis Cartilage ; 24(9): 1528-34, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27090577

RESUMO

OBJECTIVE: To investigate the effects of pain coping skills training (PCST) and a lifestyle behavioral weight management (BWM) program on inflammatory markers and biomarker associations with pain and function in the OA LIFE study. METHOD: Serum samples were available from a subset (N = 169) of the overweight or obese knee OA participants in the OA LIFE study that evaluated: PCST, BWM, combined PCST + BWM, or standard care (SC). Inflammatory markers (hsCRP, IL-1ra, IL-1ß, IL-6, IL-8, TNF-α, TNFRI, TNFRII, and hyaluronic acid (HA)), and adipokines (leptin and adiponectin) were measured before and after the 24-week treatment period. Biomarkers were assessed for effects of treatment and for associations with change in weight, pain and disability (unadjusted and adjusted for age, race, sex, baseline body mass index (BMI), and baseline biomarker concentration). RESULTS: PCST + BWM was associated with significant reductions in hsCRP (P = 0.0014), IL-6 (P = 0.0075), and leptin (P = 0.0001). After adjustment, there was a significant effect of PCST + BWM on changes in leptin (b = -0.19, P = 0.01) and IL-6 (b = -0.25, P = 0.02) relative to SC. Reductions in leptin and IL-6 were significantly correlated with reductions in weight, BMI and Western Ontario and McMaster Universities Arthritis Index (WOMAC) pain; reductions in IL-6 were correlated with improvements in WOMAC and Arthritis Impact Measurement Scales (AIMS) physical function. By mediation analyses, weight loss was responsible for 54% of the change in IL-6 and all of the change in leptin. CONCLUSIONS: OA-related inflammatory markers were reduced by a 24-week combined PCST + BWM intervention. This suggests that the inflammatory state can be successfully modified in the context of a readily instituted clinical intervention with a positive clinical outcome.


Assuntos
Osteoartrite do Joelho , Adipócitos , Biomarcadores , Cognição , Humanos , Inflamação , Ontário
4.
Phys Rev Lett ; 116(7): 071301, 2016 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-26943526

RESUMO

The CDMS low ionization threshold experiment (CDMSlite) uses cryogenic germanium detectors operated at a relatively high bias voltage to amplify the phonon signal in the search for weakly interacting massive particles (WIMPs). Results are presented from the second CDMSlite run with an exposure of 70 kg day, which reached an energy threshold for electron recoils as low as 56 eV. A fiducialization cut reduces backgrounds below those previously reported by CDMSlite. New parameter space for the WIMP-nucleon spin-independent cross section is excluded for WIMP masses between 1.6 and 5.5 GeV/c^{2}.

5.
BJOG ; 123(9): 1462-70, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27001034

RESUMO

OBJECTIVES: To compare the clinical effectiveness and cost-effectiveness of labour induction methods. METHODS: We conducted a systematic review of randomised trials comparing interventions for third-trimester labour induction (search date: March 2014). Network meta-analysis was possible for six of nine prespecified key outcomes: vaginal delivery within 24 hours (VD24), caesarean section, uterine hyperstimulation, neonatal intensive care unit (NICU) admissions, instrumental delivery and infant Apgar scores. We developed a decision-tree model from a UK NHS perspective and calculated incremental cost-effectiveness ratios, expected costs, utilities and net benefit, and cost-effectiveness acceptability curves. MAIN RESULTS: In all, 611 studies comparing 31 active interventions were included. Intravenous oxytocin with amniotomy and vaginal misoprostol (≥50 µg) were most likely to achieve VD24. Titrated low-dose oral misoprostol achieved the lowest odds of caesarean section, but there was considerable uncertainty in ranking estimates. Vaginal (≥50 µg) and buccal/sublingual misoprostol were most likely to increase uterine hyperstimulation with high uncertainty in ranking estimates. Compared with placebo, extra-amniotic prostaglandin E2 reduced NICU admissions. There were insufficient data to conduct analyses for maternal and neonatal mortality and serious morbidity or maternal satisfaction. Conclusions were robust after exclusion of studies at high risk of bias. Due to poor reporting of VD24, the cost-effectiveness analysis compared a subset of 20 interventions. There was considerable uncertainty in estimates, but buccal/sublingual and titrated (low-dose) misoprostol showed the highest probability of being most cost-effective. CONCLUSIONS: Future trials should be designed and powered to detect a method that is more cost-effective than low-dose titrated oral misoprostol. TWEETABLE ABSTRACT: New study ranks methods to induce labour in pregnant women on effectiveness and cost.


Assuntos
Amniotomia , Cesárea/estatística & dados numéricos , Extração Obstétrica/estatística & dados numéricos , Unidades de Terapia Intensiva Neonatal/estatística & dados numéricos , Trabalho de Parto Induzido/métodos , Ocitócicos , Administração Intravaginal , Administração Intravenosa , Administração Sublingual , Índice de Apgar , Análise Custo-Benefício , Parto Obstétrico/estatística & dados numéricos , Dinoprostona , Feminino , Humanos , Misoprostol , Metanálise em Rede , Ocitocina , Gravidez
6.
Phys Rev Lett ; 114(11): 111302, 2015 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-25839256

RESUMO

While the standard model of particle physics does not include free particles with fractional charge, experimental searches have not ruled out their existence. We report results from the Cryogenic Dark Matter Search (CDMS II) experiment that give the first direct-detection limits for cosmogenically produced relativistic particles with electric charge lower than e/6. A search for tracks in the six stacked detectors of each of two of the CDMS II towers finds no candidates, thereby excluding new parameter space for particles with electric charges between e/6 and e/200.

7.
Phys Rev Lett ; 112(4): 041302, 2014 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-24580434

RESUMO

SuperCDMS is an experiment designed to directly detect weakly interacting massive particles (WIMPs), a favored candidate for dark matter ubiquitous in the Universe. In this Letter, we present WIMP-search results using a calorimetric technique we call CDMSlite, which relies on voltage-assisted Luke-Neganov amplification of the ionization energy deposited by particle interactions. The data were collected with a single 0.6 kg germanium detector running for ten live days at the Soudan Underground Laboratory. A low energy threshold of 170 eVee (electron equivalent) was obtained, which allows us to constrain new WIMP-nucleon spin-independent parameter space for WIMP masses below 6 GeV/c2.

8.
Phys Rev Lett ; 112(24): 241302, 2014 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-24996080

RESUMO

We report a first search for weakly interacting massive particles (WIMPs) using the background rejection capabilities of SuperCDMS. An exposure of 577 kg days was analyzed for WIMPs with mass <30 GeV/c(2), with the signal region blinded. Eleven events were observed after unblinding. We set an upper limit on the spin-independent WIMP-nucleon cross section of 1.2×10(-42) cm(2) at 8 GeV/c(2). This result is in tension with WIMP interpretations of recent experiments and probes new parameter space for WIMP-nucleon scattering for WIMP masses <6 GeV/c(2).

9.
Acta Psychiatr Scand ; 130(3): 181-92, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24697518

RESUMO

OBJECTIVE: Various control conditions have been employed in psychotherapy trials, but there is growing suspicion that they may lead to different effect size estimates. The present study aims to examine the differences among control conditions including waiting list (WL), no treatment (NT) and psychological placebo (PP). METHOD: We comprehensively searched for all randomized controlled trials (RCTs) comparing cognitive-behaviour therapies (CBT) against various control conditions in the acute phase treatment of depression, and applied network meta-analysis (NMA) to combine all direct and indirect comparisons among the treatment and control arms. RESULTS: We identified 49 RCTs (2730 participants) comparing WL, NT, PP and CBT. This network of evidence was consistent, and the effect size estimates for CBT were substantively different depending on the control condition. The odds ratio of response for NT over WL was statistically significant at 2.9 (95% CI: 1.3-5.7). However, the quality of evidence, including publication bias, was less than ideal and none of the preplanned sensitivity analyses limiting to high-quality studies could be conducted, while findings of significant differences did not persist in post hoc sensitivity analyses trying to adjust for publication bias. CONCLUSION: There may be important differences in control conditions currently used in psychotherapy trials.


Assuntos
Terapia Cognitivo-Comportamental/normas , Depressão/terapia , Transtorno Depressivo Maior/terapia , Efeito Nocebo , Placebos , Ensaios Clínicos Controlados Aleatórios como Assunto/normas , Listas de Espera , Adulto , Humanos
10.
Int J Clin Pract ; 68(10): 1181-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25269948

RESUMO

The aim of this study was to develop a user-friendly checklist for critical appraisal of indirect comparisons of drugs, considering clinical, methodological/statistical and quality aspects, mainly to be applied in drug evaluation in the decision-making context. After conducting a review of the literature, we used group consensus to establish the key points of the checklist, focusing mainly on indirect comparisons, but including topics related to network meta-analysis or multiple treatment comparisons. The coordinating group elaborated the first draft, which was reviewed by external experts, re-evaluated by the coordinating group and finally assessed by 23 drug evaluation experts trained in indirect comparisons, who applied the checklist to one study. The Kappa index of agreement was calculated and the final checklist was developed by group consensus including the external experts. The checklist has two parts. The first consists of three eliminatory key questions while the second includes 17 items: 5 regarding quality, 5 regarding clinical issues and 7 dealing with methodology/statistics. The median kappa values of the 23 evaluations were 0.83 (range 0.67-0.93), 0.61 (0.54-0.91) and 0.36 (0.22-1) with regard to quality, clinical aspects and methodology/statistics, respectively. A structured checklist was developed to facilitate critical appraisal of key issues in indirect comparisons, including comments for assessing the consequences of its application to drug evaluation in the decision-making context. Agreement between reviewers in clinical and quality items was good, but weaker in methodology/statistics ones.


Assuntos
Benchmarking , Lista de Checagem , Técnicas de Apoio para a Decisão , Medicina Baseada em Evidências/métodos , Medicina Baseada em Evidências/normas , Humanos
11.
Phys Rev Lett ; 111(25): 251301, 2013 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-24483735

RESUMO

We report results of a search for weakly interacting massive particles (WIMPS) with the silicon detectors of the CDMS II experiment. This blind analysis of 140.2 kg day of data taken between July 2007 and September 2008 revealed three WIMP-candidate events with a surface-event background estimate of 0.41(-0.08)(+0.20)(stat)(-0.24)(+0.28)(syst). Other known backgrounds from neutrons and 206Pb are limited to <0.13 and <0.08 events at the 90% confidence level, respectively. The exposure of this analysis is equivalent to 23.4 kg day for a recoil energy range of 7-100 keV for a WIMP of mass 10 GeV/c2. The probability that the known backgrounds would produce three or more events in the signal region is 5.4%. A profile likelihood ratio test of the three events that includes the measured recoil energies gives a 0.19% probability for the known-background-only hypothesis when tested against the alternative WIMP+background hypothesis. The highest likelihood occurs for a WIMP mass of 8.6 GeV/c2 and WIMP-nucleon cross section of 1.9×10(-41) cm2.

12.
Curr Microbiol ; 66(2): 132-7, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23086537

RESUMO

Previous research conducted in our laboratory found a significant prevalence of multi-drug resistant (MDR) Salmonella and MDR Escherichia coli (MDR EC) in dairy calves and suggests that the MDR EC population may be an important reservoir for resistance elements that could potentially transfer to Salmonella. Therefore, the objective of the current research was to determine if resistance transfers from MDR EC to susceptible strains of inoculated Salmonella. The experiment utilized Holstein calves (approximately 3 weeks old) naturally colonized with MDR EC and fecal culture negative for Salmonella. Fecal samples were collected for culture of Salmonella and MDR EC throughout the experiment following experimental inoculation with the susceptible Salmonella strains. Results initially suggested that resistance did transfer from the MDR E. coli to the inoculated strains of Salmonella, with these stains demonstrating resistance to multiple antibiotics following in vivo exposure to MDR EC. However, serogrouping and serotyping results from a portion of the Salmonella isolates recovered from the calves post-challenge, identified two new strains of Salmonella; therefore transfer of resistance was not demonstrated under these experimental conditions.


Assuntos
Farmacorresistência Bacteriana , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Transferência Genética Horizontal , Salmonella/efeitos dos fármacos , Salmonella/genética , Animais , Bovinos , Modelos Animais de Doenças , Infecções por Escherichia coli/microbiologia , Trato Gastrointestinal/microbiologia , Salmonelose Animal/microbiologia
13.
Clin Oncol (R Coll Radiol) ; 35(2): e227-e234, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36528474

RESUMO

AIMS: The effect of the COVID-19 pandemic on cancer radiotherapy services is largely unknown. The aim of the present study was to investigate the impact of the resultant contingency plans on radiotherapy cancer services in Scotland. MATERIALS AND METHODS: Detailed data of radiotherapy activity at our centre were collected from 1 April 2019 to 31 March 2021. Differences in mean weekly radiotherapy courses, dose and fractionation patterns and treatment intent were compared with corresponding pre-pandemic months for all treatment sites. Qualitative data were collected for a subgroup of radical radiotherapy patients. RESULTS: Total radiotherapy courses decreased from 6968 to 6240 (-10%) compared with the previous year, prior to the pandemic. Average weekly radiotherapy courses delivered were 134 (standard deviation ±13), decreasing by 10% to 120 (standard deviation 15) (Welch's t-test, P < 0.001). The greatest decrease in new start treatment courses was observed from May to August 2020 (-7.7%, -24.0%, -16.7% and -18.7%) compared with the corresponding months in 2019. A significant reduction was seen for female patients <70 years (-16%) compared with females >70 years (-8%) or their male counterparts (-7% and -6%, respectively). By diagnosis, the largest reductions between pre- and post-pandemic levels were for anal (-26%), breast (-18%) and prostate (-14%) cancer. Contrarily, a significant increase was found for bladder (28%) and oesophageal (11%) cancers. CONCLUSIONS: Over the first 12 months of the COVID-19 pandemic, radiotherapy activity significantly decreased compared with the 12 months prior. Due to issued guidance, the use of hypofractionated regimens increased, contributing to the reduction in treatments for some tumour sites. An increase in other tumour sites can probably be attributed to the reduction or cancellation of surgical interventions. These results will inform our understanding of the indirect consequences of the pandemic on radiotherapy services.


Assuntos
COVID-19 , Neoplasias , Humanos , Masculino , Feminino , COVID-19/epidemiologia , Pandemias , Neoplasias/epidemiologia , Neoplasias/radioterapia , Escócia/epidemiologia , Fracionamento da Dose de Radiação
14.
Poult Sci ; 91(9): 2089-95, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22912441

RESUMO

The current experiment was conducted to determine the effect of mycotoxin-contaminated diets with aflatoxin (AFLA) and deoxynivalenol (DON) and dietary inclusion of deactivation compound on layer hen performance during a 10-wk trial. The experimental design consisted of a 4 × 2 factorial with 4 toxin levels: control, low (0.5 mg/kg AFLA + 1.0 mg/kg DON), medium (1.5 mg/kg AFLA + 1.5 mg/kg DON), and high (2.0 mg/kg AFLA + 2.0 mg/kg DON) with or without the inclusion of deactivation compound. Three hundred eighty-four 25-wk-old laying hens were randomly assigned to 1 of the 8 treatment groups. Birds were fed contaminated diets for a 6-wk phase of toxin administration followed by a 4-wk recovery phase, when all birds were fed mycotoxin-free diets. Twelve hens from each treatment were subjected to necropsy following each phase. Relative liver and kidney weights were increased (P < 0.05) at the medium and high toxin levels following the toxin phase, but the deactivation compound reduced (P < 0.05) relative liver and kidney weights following the recovery period. The high toxin level decreased (P < 0.05) feed consumption and egg production during the toxin period, whereas the deactivation compound increased (P < 0.05) egg production during the first 2 wk of the toxin phase. Egg weights were reduced (P < 0.05) in hens fed medium and high levels of toxin. An interaction existed between toxin level and deactivation compound inclusion with regard to feed conversion (g of feed/g of egg). High inclusion level of toxins increased feed conversion compared with the control diet, whereas deactivation compound inclusion reduced feed conversion to a level comparable with the control. These data indicate that deactivation compound can reduce or eliminate adverse effects of mycotoxicoses in peak-performing laying hens.


Assuntos
Aflatoxinas/toxicidade , Ração Animal/análise , Galinhas/fisiologia , Dieta/veterinária , Contaminação de Alimentos , Tricotecenos/toxicidade , Aflatoxinas/antagonistas & inibidores , Aflatoxinas/química , Animais , Suplementos Nutricionais , Esquema de Medicação , Feminino , Rim/anatomia & histologia , Rim/efeitos dos fármacos , Fígado/anatomia & histologia , Fígado/efeitos dos fármacos , Baço/anatomia & histologia , Baço/efeitos dos fármacos , Tricotecenos/antagonistas & inibidores , Tricotecenos/química
15.
Poult Sci ; 91(9): 2096-104, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22912442

RESUMO

An experiment was conducted to determine the effect of dietary inclusion of Mycofix Select (Biomin GmbH, Herzogenburg, Austria) on discrete egg parameters and quality characteristics of hens fed mycotoxin-contaminated diets (aflatoxin; AFLA) and deoxynivalenol (DON)) during a 10-wk trial. A 4 × 2 factorial design was used with 4 contamination levels: control, low (0.5 mg/kg of AFLA + 1.0 mg/kg of DON), medium (1.5 mg/kg of AFLA + 1.5 mg/kg of DON), and high (2.0 mg/kg of AFLA + 2.0 mg/kg of DON) with or without the inclusion of mycotoxin deactivating compound. Three hundred and eighty-four 25-wk-old laying hens were housed 3 per cage. Birds were fed contaminated diets for a 6-wk phase of toxin administration followed by a 4-wk recovery phase, when all birds were fed mycotoxin-free diets. Parameters evaluated included egg weight, Haugh unit value, specific gravity, eggshell thickness, egg shape index, and relative albumen and yolk weights. Albumen height and Haugh unit value were depressed (P < 0.05) at the high mycotoxin level 2 wk postinclusion. Egg weight was significantly reduced (P < 0.05) with the high toxins level by the third week of toxin administration and remained throughout the study during toxin administration. Egg shape index indicated a variation (P < 0.05) in shape with all toxin levels compared with the control. Relative yolk weight was decreased (P < 0.05) by the high toxin level. An interaction existed between the deactivating compound inclusion and toxins level with regard to specific gravity. Following the toxin phase, the deactivating compound inclusion increased (P < 0.05) egg specific gravity in the control and low toxin groups whereas a decrease (P < 0.05) was observed at the high toxin level. These data indicate that mycotoxins present in feed can reduce egg quality, size, yolk weight, and alter egg shape and that inclusion of a mycotoxin deactivating compound can ameliorate some of the negative effects of mycotoxin consumption.


Assuntos
Aflatoxinas/toxicidade , Ração Animal/análise , Galinhas/fisiologia , Dieta/veterinária , Contaminação de Alimentos , Tricotecenos/toxicidade , Aflatoxinas/antagonistas & inibidores , Aflatoxinas/química , Animais , Suplementos Nutricionais , Esquema de Medicação , Casca de Ovo/efeitos dos fármacos , Feminino , Tricotecenos/antagonistas & inibidores , Tricotecenos/química
16.
Phys Med Biol ; 67(3)2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35038692

RESUMO

Objective. Mammogram image quality in European breast screening systems is defined by threshold gold thickness (T) assessment of the CDMAM contrast-detail phantom. Previous studies have outlined several limitations of the phantom including expense, number of images required and inter-phantom manufacturing variability. Two alternative approaches to image quality assessment for routine quality control are examined and compared to the CDMAM technique: (i) A detectability index (d') based on a non-prewhitened model observer with an eye filter (NPWE) and(ii) A statistical estimate of contrast based on image noise levels (CSTAT).Approach. Thed' calculation follows a previously published methodology based on the NNPS and contrast, both measured from an image of 5 cm of PMMA containing a 0.2 mm Al target, as well as the MTF measured under standard conditions. For the proposed statistical method, pixels in the centre of the same NNPS image were re-binned into a range of equivalent CDMAM target areas. For any area, the minimum contrast necessary to distinguish a signal from the background,CSTAT, is 3.29σat a 95% level of confidence, whereσis the standard deviation of the background pixels. Theoretical analysis predicts a simple relationships betweenCSTAT,Tandd'. Measured values ofCSTATwere compared toTandd' as a function of air kerma at the detector for ten digital mammography systems from three different manufacturers.Main Results. Theoretical relationships betweenCSTAT,d' andTwere demonstrated. Minimum acceptable image quality performance for 0.10 and 0.25 mm diameter discs, defined by the European Guidelines in terms ofT, are equivalent tod' values of 0.85 and 5.36 and thresholdCSTATvalues of 0.055 and 0.022.Significance. Strong correlations between log(T), log(d') and log(CSTAT) suggest that either alternative approach produces information corresponding to that obtained using the CDMAM.CSTATshould be considered as a simple, objective and cost-effective alternative to routine image quality assessment in mammography.


Assuntos
Mamografia , Intensificação de Imagem Radiográfica , Mama , Mamografia/métodos , Imagens de Fantasmas , Controle de Qualidade , Intensificação de Imagem Radiográfica/métodos
17.
Phys Rev Lett ; 106(13): 131302, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21517371

RESUMO

We report results from a reanalysis of data from the Cryogenic Dark Matter Search (CDMS II) experiment at the Soudan Underground Laboratory. Data taken between October 2006 and September 2008 using eight germanium detectors are reanalyzed with a lowered, 2 keV recoil-energy threshold, to give increased sensitivity to interactions from weakly interacting massive particles (WIMPs) with masses below ∼10 GeV/c(2). This analysis provides stronger constraints than previous CDMS II results for WIMP masses below 9 GeV/c(2) and excludes parameter space associated with possible low-mass WIMP signals from the DAMA/LIBRA and CoGeNT experiments.

18.
Poult Sci ; 90(6): 1324-8, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21597074

RESUMO

Most current research on Campylobacter has focused on preharvest or processing plant cross-contamination. Little is known about the effect of storage environment on the survival of Campylobacter on raw poultry. We evaluated the effects of modified storage atmosphere and freezing on the survival of naturally occurring Campylobacter on raw poultry. Broiler carcasses (n = 560) were collected as they exited the chiller in 2 commercial processing plants and were sampled for the detection of Campylobacter, Escherichia coli, psychrophiles, and total aerobes at 0 and 14 d of refrigerated (2°C) storage. Gases evaluated were air, 100% O(2), 100% CO(2), and a standard poultry modified atmosphere packaging mixture (5% O(2) + 10% CO(2) + 85% N). Freezing was included as a control group. All carcasses were sampled by the whole-carcass rinse method. The rinse fluid was recovered and pooled from 5 individual rinses, and serial dilutions were made for examination of Campylobacter (42°C, 48 h), E. coli (37°C, 24 h), psychrophiles (plate count agar, 4°C, 7 d), and total aerobic bacterial populations (plate count agar, 37°C, 24 h). Campylobacter counts for all treatments were reduced during the 14-d storage period but the 100% O(2) treatment caused a significantly (P < 0.05) greater reduction than the other gas treatments. For the psychrophiles, storage in air resulted in the greatest growth after 14 d, with reduced psychrophilic growth allowed by either O(2) or the modified atmosphere packaging mixture (not different from each other). Of the treatments evaluated, CO(2) allowed the least growth of psychrophiles. Proliferation of E. coli and aerobes was the greatest when packaged in air after 14 d, whereas CO(2) packaging resulted in the least growth. These data suggest that storage under O(2) may reduce Campylobacter recovery and slow psychrophile and aerobe recovery following storage.


Assuntos
Campylobacter/fisiologia , Microbiologia de Alimentos , Embalagem de Alimentos/métodos , Carne/microbiologia , Animais , Galinhas/microbiologia
19.
Poult Sci ; 90(8): 1652-8, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21753199

RESUMO

Probiotics are nonpathogenic bacteria that can promote bird health by reducing pathogen colonization. Researchers have previously demonstrated that the avian immune response can be modulated with probiotics, which may provide a mechanism for the reported reductions in pathogens. We examined phagocyte oxidative burst and cell proliferation of vaccinated broilers administered probiotics. We hypothesized that the combination of probiotic bacteria and a vaccine would affect immune function. Two studies were conducted to evaluate this interaction in broilers. Treatments consisted of a negative control, probiotic, vaccine, or a probiotic + vaccine. Peripheral blood was collected on d 7, 14, and 21 of age. Heterophils and monocytes were evaluated for oxidative burst and lymphocytes were assayed for proliferation. In study 1, heterophil oxidative burst was higher (P ≤ 0.05) in each treatment that received probiotic on d 14 when compared with the negative control. On d 21, an enhanced (P ≤ 0.05) heterophil oxidative burst was observed in the probiotic treatment when compared with the other treatments. On d 14, monocyte oxidative burst was greater (P ≤ 0.05) in the probiotic + vaccine treatment when compared with all other treatments. An increase (P ≤ 0.05) in lymphocyte proliferation was observed among all treatments on d 7 when compared with the negative control. Both vaccine treatments had significant lymphocyte proliferation on d 14 when compared with the negative control. In study 2, the probiotic treatment was associated with greater levels in heterophil oxidative burst on d 7 when compared with all other treatments. On d 21, an increase (P ≤ 0.05) in heterophil oxidative burst was seen in the vaccine treatment when compared with the negative control. On d 7, increased (P ≤ 0.05) monocyte oxidative burst was observed in the vaccine treatment when compared with the negative control. No significant differences were observed in lymphocyte proliferation in any of the treatment groups. These data suggest that probiotics can modulate the immune response and may play a role in vaccination.


Assuntos
Galinhas , Coccidiose/veterinária , Imunidade Inata/efeitos dos fármacos , Doenças das Aves Domésticas/prevenção & controle , Probióticos/farmacologia , Vacinas Protozoárias/imunologia , Animais , Proliferação de Células , Coccidiose/prevenção & controle , Esquema de Medicação , Leucócitos/fisiologia , Linfócitos/citologia , Linfócitos/fisiologia , Masculino , Explosão Respiratória
20.
Poult Sci ; 90(5): 990-5, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21489944

RESUMO

Two experiments were conducted to determine whether Eimeria tenella oocyst output in cecal and fecal contents, lesion development, and performance characteristics were affected by ad libitum versus restricted feeding and challenge level. In experiment 1, 144 Cobb 500 males were placed in battery cages with 6 chicks/pen. On d 20, half of the battery pens were placed on feed restriction and all broilers were orally challenged with Eimeria tenella oocysts at one of 3 challenge levels (0, 5,000, or 20,000 sporulated oocysts). Cecal and fecal material were collected separately from d 4 postchallenge through d 10 postchallenge for oocysts output (oocysts shed/g) determination. Six days postchallenge, 3 broilers from each pen were removed and subjected to necropsy for lesion assessment. In experiment 2, 96 Cobb 500 males were placed in identical battery pens with 8 chicks/pen. On d 14, restricted feeding was initiated and broilers were challenged with Eimeria tenella oocysts at one of 3 challenge levels (1,000, 5,000, or 20,000 oocysts). Twenty-four hour collections of cecal and fecal material were obtained separately from d 4 postchallenge through d 10 postchallenge for oocysts per gram and total output determination. Six days postchallenge, 4 broilers from each pen were removed and subjected to necropsy for lesion assessment. In both experiments, BW gain was not affected by challenge dose in either the ad libitum-fed or restrict-fed broilers. Increased lesion development was observed with increasing challenge levels, and oocyst shedding peaked between d 7 and 9 postchallenge in both experiments. Oocyst concentration was higher in cecal droppings compared with fecal material throughout peak shedding; however, total oocyst output for the challenge period was similar between fecal material and cecal droppings.


Assuntos
Ceco/parasitologia , Galinhas , Coccidiose/veterinária , Eimeria tenella/fisiologia , Fezes/parasitologia , Animais , Coccidiose/parasitologia , Masculino , Oocistos
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