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1.
Cytotherapy ; 2024 May 10.
Article in English | MEDLINE | ID: mdl-38775773

ABSTRACT

BACKGROUND: Hematopoietic cell transplantation (HCT) is a promising treatment for hematological diseases, yet access barriers like cost and limited transplant centers persist. Telemedicine-based patient navigation (PN) has emerged as a solution. This study presents a cost-free PN telemedicine clinic (TC) in collaboration with the National Marrow Donor Program. AIM: to assess its feasibility and impac on HCT access determined by the cumulative incidence of transplantation. METHODS: In this single-center cohort study, patients of all ages and diagnoses referred for HCT participated. Two transplant physician-navigators established patient relationships via video calls, collecting medical history, offering HCT education and recommending pretransplant tests. The analysis involved descriptive statistics and intent-to-transplant survival assessment. RESULTS: One hundred and three patients were included of whom n = 78 were referred for allogeneic HCT (alloHCT), with a median age of 28 years. The median time from initial contact to the first consult was 5 days. The cumulative incidence of transplantation was 50% at 6 months and 61% at 12 months, with varying outcomes based on HCT type. Notably, 49 patients were not transplanted, primarily due to refractory disease, progression or relapse (57.1%). Autologous HCT candidates and physician referrals were correlated with higher transplant success compared to alloHCT candidates and patients who were not referred by a physician. CONCLUSION: Our pretransplant TC was feasible, facilitating access to HCT. Disease relapse posed a significant barrier. Enhancing timely physician referrals should be a focus for future efforts.

2.
J Dairy Sci ; 106(12): 8611-8626, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37641244

ABSTRACT

We evaluated the effects of supplementing bacterial direct-fed microbial (DFM) on performance, apparent total-tract digestibility, rumen fermentation, and immune parameters of lactating dairy cows. One hundred fourteen multiparous Holstein cows (41 ± 7 DIM) were used in a randomized complete block design with an experiment comprising 14 d of a covariate (pre-experimental sample and data collection) and 91 d of an experimental period. Cows were blocked based on energy-corrected milk (ECM) yield during the covariate period and the following treatments were randomly assigned within each block: (1) control (CON), corn silage-based total mixed ration without DFM; (2) PRO-A, basal diet top-dressed with a mixture of Lactobacillus animalis and Propionibacterium freudenreichii at 3 × 109 cfu/d; and 3) PRO-B, basal diet top-dressed with a mixture of L. animalis, P. freudenreichii, Bacillus subtilis, and Bacillus licheniformis at 11.8 × 109 cfu/d. Milk yield, dry matter intake (DMI), and body weight were measured daily, while milk samples for component analysis were taken on 2 consecutive days of each week of data collection. Feces, urine, rumen, and blood samples were taken during the covariate period, wk 4, 7, 10, and 13 for estimation of digestibility, N-partitioning, rumen fermentation, plasma nutrient status and immune parameters. Treatments had no effect on DMI and milk yield. Fat-corrected milk (3.5% FCM) and milk fat yield were improved with PRO-B, while milk fat percent and feed efficiency (ECM/DMI) tended to increase with PRO-B compared with PRO-A and CON. Crude fat digestibility was greater with PRO-B compared with CON. Feeding CON and PRO-A resulted in higher total volatile fatty acid concentration relative to PRO-B. Percentage of neutrophils tended to be reduced with PRO-A compared with CON and PRO-B. The mean fluorescence intensity (MFI) of anti-CD44 antibody on granulocytes tended to be higher in PRO-B compared with CON. The MFI of anti-CD62L antibody on CD8+ T cells was lower in PRO-A than PRO-B, with PRO-A also showing a tendency to be lower than CON. This study indicates the potential of DFM to improve fat digestibility with consequential improvement in fat corrected milk yield, feed efficiency and milk fat yield by lactating dairy cows. The study findings also indicate that dietary supplementation with DFM may augment immune parameters or activation of immune cells, including granulocytes and T cells; however, the overall effects on immune parameters are inconclusive.


Subject(s)
Animal Feed , Lactation , Female , Cattle , Animals , Lactation/physiology , Animal Feed/analysis , Milk , Diet/veterinary , Digestion , Dietary Supplements/analysis , Rumen
3.
J Dairy Sci ; 105(3): 2301-2314, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34955263

ABSTRACT

The objective of this experiment was to evaluate the effects of supplementing a rumen-protected source of Met, N-acetyl-l-methionine (NALM), on lactational performance and nitrogen metabolism in early- to mid-lactation dairy cows. Sixty multiparous Holstein dairy cows in early lactation (27 ± 4.3 d in milk, SD) were assigned to 4 treatments in a randomized complete block design. Cows were blocked by actual milk yield. Treatments were as follows: (1) no NALM (control); (2) 15 g/d of NALM (NALM15); (3) 30 g/d of NALM (NALM30); and (4) 45 g/d of NALM (NALM45). Diets were formulated using a Cornell Net Carbohydrate and Protein System (CNCPS) v.6.5 model software to meet or exceed nutritional requirements of lactating dairy cows producing 42 kg/d of milk and to undersupply metabolizable Met (control) or supply incremental amounts of NALM. The digestible Met (dMet) supply for control, NALM15, NALM30, and NALM45 were 54.7, 59.8, 64.7, and 72.2 g/d, respectively. The supply of dMet was 88, 94, 104, and 115% of dMet requirement for control, NALM15, NALM30, and NALM45, respectively. Milk yield data were collected, dry matter intake (DMI) was measured daily, and milk samples were collected twice per week for 22 wk. Blood, ruminal fluid, urine, and fecal samples were collected during the covariate period and during wk 4, 8, and 16. Data were analyzed using the GLIMMIX procedure of SAS (SAS Institute) using covariates in the model for all variables except body weight. Linear, quadratic, and cubic contrasts were also tested. Treatments did not affect DMI, milk yield, and milk component concentration and yield; however, feed efficiency expressed as milk yield per DMI and 3.5% fat-corrected milk per DMI were quadratically affected, with greater response observed for NALM15 and NALM30 compared with control. Acetate proportion linearly increased, whereas propionate proportion linearly decreased with NALM supplementation. Blood urea nitrogen linearly decreased with NALM supplementation. Total plasma essential AA concentrations were quadratically affected, as greater values were observed for control and NALM45 than other treatments. Plasma Met concentration was quadratically affected as lower levels were observed with NALM15, whereas Met concentrations increased with NALM45 compared with control. Nitrogen utilization efficiency and apparent total-tract nutrient digestibility were not affected by treatment. Supplementation of NALM at 15 or 30 g/head per day resulted in the greatest improvements in feed efficiency without affecting N metabolism of early- to mid-lactation dairy cows.


Subject(s)
Lactation , Rumen , Animal Feed/analysis , Animals , Cattle , Diet/veterinary , Dietary Supplements , Female , Lactation/physiology , Methionine , Milk/metabolism , Rumen/metabolism
4.
Eur Phys J C Part Fields ; 81(4): 337, 2021.
Article in English | MEDLINE | ID: mdl-34720714

ABSTRACT

The selection of low-radioactive construction materials is of utmost importance for the success of low-energy rare event search experiments. Besides radioactive contaminants in the bulk, the emanation of radioactive radon atoms from material surfaces attains increasing relevance in the effort to further reduce the background of such experiments. In this work, we present the 222 Rn emanation measurements performed for the XENON1T dark matter experiment. Together with the bulk impurity screening campaign, the results enabled us to select the radio-purest construction materials, targeting a 222 Rn activity concentration of 10 µ Bq / kg in 3.2 t of xenon. The knowledge of the distribution of the 222 Rn sources allowed us to selectively eliminate problematic components in the course of the experiment. The predictions from the emanation measurements were compared to data of the 222 Rn activity concentration in XENON1T. The final 222 Rn activity concentration of ( 4.5 ± 0.1 ) µ Bq / kg in the target of XENON1T is the lowest ever achieved in a xenon dark matter experiment.

5.
J Dairy Sci ; 104(7): 7671-7681, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33814135

ABSTRACT

We previously reported that milk production in dairy cows was increased by adding a specific xylanase-rich exogenous fibrolytic enzyme (XYL) to a total mixed ration (TMR) containing 10% bermudagrass silage (BMD). Two follow-up experiments were conducted to examine whether adding XYL would increase the performance of dairy cows consuming a TMR containing a higher (20%) proportion of BMD (Experiment 1) and to evaluate the effects of XYL on in vitro fermentation and degradability of the corn silage, BMD, and TMR (Experiment 2). In Experiment 1, 40 lactating Holstein cows in early lactation (16 multiparous and 24 primiparous; 21 ± 3 d in milk; 589 ± 73 kg of body weight) were blocked by milk yield and parity and randomly assigned to the Control and XYL treatments. The TMR contained 20% BMD, 25% corn silage, 8% wet brewer's grain, and 47% concentrate mixture in the dry matter (DM). Cows were fed the XYL-treated or untreated experimental TMR twice per day for 10 wk after a 9-d covariate period. In Experiment 2, ruminal fluid was collected from 3 cannulated lactating Holstein cows fed a diet containing 20% bermudagrass haylage, 25% corn silage and 55% concentrate. In Experiment 1, compared with Control, application of XYL did not affect DM intake (24.0 vs. 23.7 kg/d), milk yield (35.1 vs. 36.2 kg/d), fat-corrected milk yield (36.1 vs. 36.9 kg/d), or yields of milk fat (1.29 vs. 1.31 kg/d) or protein (1.07 vs. 1.08 kg/d). However, intake of neutral detergent fiber (4.67 vs. 4.41 kg/d) tended to increase with XYL; consequently, milk protein concentration was increased by XYL (3.02 vs. 2.95%). Feed efficiency tended to be lower in cows fed XYL (1.57 vs. 1.52 kg of fat-corrected milk/kg of DM intake) compared with Control. In Experiment 2, XYL tended to increase the rate of gas production in the TMR, the molar proportion of propionate for corn silage, and that of valerate for the TMR. In addition, XYL increased in vitro DM, neutral detergent fiber, and acid detergent fiber degradability of BMD and corn silage. Application of XYL to a diet with a relatively high proportion of BMD tended to increase digestible neutral detergent fiber intake, increased milk protein concentration, and in vitro degradability of DM, neutral detergent fiber, and acid detergent fiber. However, XYL did not affect milk production and tended to decrease feed efficiency in early lactation cows.


Subject(s)
Lactation , Silage , Animals , Cattle , Cynodon , Diet/veterinary , Dietary Fiber , Digestion , Female , Pregnancy , Rumen , Silage/analysis , Zea mays
6.
Phys Rev Lett ; 126(9): 091301, 2021 Mar 05.
Article in English | MEDLINE | ID: mdl-33750173

ABSTRACT

We report on a search for nuclear recoil signals from solar ^{8}B neutrinos elastically scattering off xenon nuclei in XENON1T data, lowering the energy threshold from 2.6 to 1.6 keV. We develop a variety of novel techniques to limit the resulting increase in backgrounds near the threshold. No significant ^{8}B neutrinolike excess is found in an exposure of 0.6 t×y. For the first time, we use the nondetection of solar neutrinos to constrain the light yield from 1-2 keV nuclear recoils in liquid xenon, as well as nonstandard neutrino-quark interactions. Finally, we improve upon world-leading constraints on dark matter-nucleus interactions for dark matter masses between 3 and 11 GeV c^{-2} by as much as an order of magnitude.

7.
Phys Rev Lett ; 122(14): 141301, 2019 Apr 12.
Article in English | MEDLINE | ID: mdl-31050482

ABSTRACT

We report the first experimental results on spin-dependent elastic weakly interacting massive particle (WIMP) nucleon scattering from the XENON1T dark matter search experiment. The analysis uses the full ton year exposure of XENON1T to constrain the spin-dependent proton-only and neutron-only cases. No significant signal excess is observed, and a profile likelihood ratio analysis is used to set exclusion limits on the WIMP-nucleon interactions. This includes the most stringent constraint to date on the WIMP-neutron cross section, with a minimum of 6.3×10^{-42} cm^{2} at 30 GeV/c^{2} and 90% confidence level. The results are compared with those from collider searches and used to exclude new parameter space in an isoscalar theory with an axial-vector mediator.

8.
Phys Rev Lett ; 122(7): 071301, 2019 Feb 22.
Article in English | MEDLINE | ID: mdl-30848617

ABSTRACT

We present first results on the scalar coupling of weakly interacting massive particles (WIMPs) to pions from 1 t yr of exposure with the XENON1T experiment. This interaction is generated when the WIMP couples to a virtual pion exchanged between the nucleons in a nucleus. In contrast to most nonrelativistic operators, these pion-exchange currents can be coherently enhanced by the total number of nucleons and therefore may dominate in scenarios where spin-independent WIMP-nucleon interactions are suppressed. Moreover, for natural values of the couplings, they dominate over the spin-dependent channel due to their coherence in the nucleus. Using the signal model of this new WIMP-pion channel, no significant excess is found, leading to an upper limit cross section of 6.4×10^{-46} cm^{2} (90% confidence level) at 30 GeV/c^{2} WIMP mass.

9.
Phys Rev Lett ; 123(25): 251801, 2019 Dec 20.
Article in English | MEDLINE | ID: mdl-31922764

ABSTRACT

We report constraints on light dark matter (DM) models using ionization signals in the XENON1T experiment. We mitigate backgrounds with strong event selections, rather than requiring a scintillation signal, leaving an effective exposure of (22±3) tonne day. Above ∼0.4 keV_{ee}, we observe <1 event/(tonne day keV_{ee}), which is more than 1000 times lower than in similar searches with other detectors. Despite observing a higher rate at lower energies, no DM or CEvNS detection may be claimed because we cannot model all of our backgrounds. We thus exclude new regions in the parameter spaces for DM-nucleus scattering for DM masses m_{χ} within 3-6 GeV/c^{2}, DM-electron scattering for m_{χ}>30 MeV/c^{2}, and absorption of dark photons and axionlike particles for m_{χ} within 0.186-1 keV/c^{2}.

10.
Phys Rev Lett ; 123(24): 241803, 2019 Dec 13.
Article in English | MEDLINE | ID: mdl-31922867

ABSTRACT

Direct dark matter detection experiments based on a liquid xenon target are leading the search for dark matter particles with masses above ∼5 GeV/c^{2}, but have limited sensitivity to lighter masses because of the small momentum transfer in dark matter-nucleus elastic scattering. However, there is an irreducible contribution from inelastic processes accompanying the elastic scattering, which leads to the excitation and ionization of the recoiling atom (the Migdal effect) or the emission of a bremsstrahlung photon. In this Letter, we report on a probe of low-mass dark matter with masses down to about 85 MeV/c^{2} by looking for electronic recoils induced by the Migdal effect and bremsstrahlung using data from the XENON1T experiment. Besides the approach of detecting both scintillation and ionization signals, we exploit an approach that uses ionization signals only, which allows for a lower detection threshold. This analysis significantly enhances the sensitivity of XENON1T to light dark matter previously beyond its reach.

11.
Phys Rev Lett ; 121(11): 111302, 2018 Sep 14.
Article in English | MEDLINE | ID: mdl-30265108

ABSTRACT

We report on a search for weakly interacting massive particles (WIMPs) using 278.8 days of data collected with the XENON1T experiment at LNGS. XENON1T utilizes a liquid xenon time projection chamber with a fiducial mass of (1.30±0.01) ton, resulting in a 1.0 ton yr exposure. The energy region of interest, [1.4,10.6] keV_{ee} ([4.9,40.9] keV_{nr}), exhibits an ultralow electron recoil background rate of [82_{-3}^{+5}(syst)±3(stat)] events/(ton yr keV_{ee}). No significant excess over background is found, and a profile likelihood analysis parametrized in spatial and energy dimensions excludes new parameter space for the WIMP-nucleon spin-independent elastic scatter cross section for WIMP masses above 6 GeV/c^{2}, with a minimum of 4.1×10^{-47} cm^{2} at 30 GeV/c^{2} and a 90% confidence level.

12.
Sci Rep ; 8: 46942, 2018 Feb 12.
Article in English | MEDLINE | ID: mdl-29430010

ABSTRACT

This corrects the article DOI: 10.1038/srep41699.

13.
Phys Rev Lett ; 119(18): 181301, 2017 Nov 03.
Article in English | MEDLINE | ID: mdl-29219593

ABSTRACT

We report the first dark matter search results from XENON1T, a ∼2000-kg-target-mass dual-phase (liquid-gas) xenon time projection chamber in operation at the Laboratori Nazionali del Gran Sasso in Italy and the first ton-scale detector of this kind. The blinded search used 34.2 live days of data acquired between November 2016 and January 2017. Inside the (1042±12)-kg fiducial mass and in the [5,40] keV_{nr} energy range of interest for weakly interacting massive particle (WIMP) dark matter searches, the electronic recoil background was (1.93±0.25)×10^{-4} events/(kg×day×keV_{ee}), the lowest ever achieved in such a dark matter detector. A profile likelihood analysis shows that the data are consistent with the background-only hypothesis. We derive the most stringent exclusion limits on the spin-independent WIMP-nucleon interaction cross section for WIMP masses above 10 GeV/c^{2}, with a minimum of 7.7×10^{-47} cm^{2} for 35-GeV/c^{2} WIMPs at 90% C.L.

14.
Pesqui. vet. bras ; 37(11): 1313-1321, Nov. 2017. tab, graf, ilus
Article in Portuguese | LILACS, VETINDEX | ID: biblio-895376

ABSTRACT

As enfermidades fúngicas são diagnósticos diferenciais de diversas morbidades de caráter infeccioso, degenerativo ou proliferativo neoplásico, principalmente em gatos, que é a espécie mais suscetível a estas. Este trabalho descreve os achados anatomopatológicos de doenças fúngicas em gatos no período de janeiro de 2005 a dezembro de 2015 pelo SPV-UFRGS. Foram revisados 1.274 protocolos de necropsia e encontrou-se 17 casos de micoses, correspondendo a 1,33% dos diagnósticos. Quanto às amostras provenientes de biopsias, foram verificados 2.615 protocolos e detectou-se 59 casos de doenças fúngicas, totalizando 2,25% dos diagnósticos, sendo revisados seus achados macroscópicos, microscópicos, colorações especiais e cultivo micológico. O principal diagnóstico encontrado foi esporotricose com 34 casos de biópsia e cinco de necropsia. Criptococose obteve seis diagnósticos na necropsia e 13 na biópsia. O pseudomicetoma dermatofítico possui cinco casos de biópsia e dois de necropsia. Histoplasmose obteve um diagnóstico na necropsia e dois na biópsia. Aspergilose teve dois casos diagnosticados na necropsia. Candidíase e feo-hifomicose obtiveram um caso cada. Em quatro ocasiões, não se pode identificar o agente envolvido na lesão e foram classificados conforme a alteração morfológica em: dermatite fúngica, enterite fúngica, rinite micótica e dermatite e osteomielite fúngica. Através deste trabalho, pode-se identificar que a esporotricose foi o diagnóstico de doença fúngica mais frequente em felinos, seguido da criptococose e pseudomicetoma dermatofítico.(AU)


Fungal disease is included in the differential diagnosis of a wide range of disorders in cats. At the Department of Veterinary Pathology of Federal University Federal of Rio Grande do Sul (SPV-UFRGS), evaluation of records data of cats from January 2005 to December 2015 were examined. A total of 1,274 necropsy have been reviewed from which 17 cases of fungal infection was revealed accounting for 1.33%, and a total of 2,615 biopsies have been reviewed from which 59 cases of fungal infection was revealed, accounting for 2.25%. We retrospectively analyzed the gross and microscopic findings and the yield of additional diagnostic approaches employed. Sporotrichosis was the most common diagnosis with 34 cases found in biopsy and five necropsies. Cryptococcosis obtained six diagnoses through necropsy and 13 through biopsy. Dermatophytic pseudomycetoma was found in five cases in biopsy and two necropsies. Histoplasmosis diagnosis was obtained in one necropsy and two biopsies. Aspergillosis had two cases diagnosed in necropsy. Candidiase and phaeo-hyphomycosis accounted for one case each. In four occasions, it was not possible to identify the agent involved and the diagnosis was made regarding the morphological changes: fungal dermatitis, fungal enteritis, mycotic rhinitis, and fungal dermatitis and osteomyelitis. In this study, sporotrichosis could be identified as the most frequent diagnosis of fungal disease in cats, followed by cryptococcosis and dermatophytic pseudomycetoma.(AU)


Subject(s)
Animals , Cats , Cryptococcosis/veterinary , Mycoses/microbiology , Mycoses/pathology , Mycoses/veterinary , Sporotrichosis/veterinary , Aspergillosis/veterinary , Candidiasis/veterinary , Histoplasmosis/veterinary , Phaeohyphomycosis/veterinary
15.
J Immunol ; 199(8): 2803-2814, 2017 10 15.
Article in English | MEDLINE | ID: mdl-28855313

ABSTRACT

Acinetobacter baumannii is a bacterial pathogen with increasing impact in healthcare settings, due in part to this organism's resistance to many antimicrobial agents, with pneumonia and bacteremia as the most common manifestations of disease. A significant proportion of clinically relevant A. baumannii strains are resistant to killing by normal human serum (NHS), an observation supported in this study by showing that 12 out of 15 genetically diverse strains of A. baumannii are resistant to NHS killing. To expand our understanding of the genetic basis of A. baumannii serum resistance, a transposon (Tn) sequencing (Tn-seq) approach was used to identify genes contributing to this trait. An ordered Tn library in strain AB5075 with insertions in every nonessential gene was subjected to selection in NHS. We identified 50 genes essential for the survival of A. baumannii in NHS, including already known serum resistance factors, and many novel genes not previously associated with serum resistance. This latter group included the maintenance of lipid asymmetry genetic pathway as a key determinant in protecting A. baumannii from the bactericidal activity of NHS via the alternative complement pathway. Follow-up studies validated the role of eight additional genes identified by Tn-seq in A. baumannii resistance to killing by NHS but not by normal mouse serum, highlighting the human species specificity of A. baumannii serum resistance. The identification of a large number of genes essential for serum resistance in A. baumannii indicates the degree of complexity needed for this phenotype, which might reflect a general pattern that pathogens rely on to cause serious infections.


Subject(s)
Acinetobacter Infections/microbiology , Acinetobacter baumannii/genetics , Blood Bactericidal Activity , Pneumonia/microbiology , Virulence , Acinetobacter Infections/immunology , Acinetobacter baumannii/immunology , Acinetobacter baumannii/pathogenicity , Animals , Complement Pathway, Alternative/genetics , DNA Transposable Elements/genetics , DNA, Bacterial/analysis , Humans , Lipid Metabolism/genetics , Mice , Pneumonia/immunology , Serum Response Factor/genetics , Species Specificity , Transcriptome , Virulence/genetics
16.
J Dairy Sci ; 100(9): 7198-7210, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28711253

ABSTRACT

The objectives were to examine the aflatoxin B1 (AFB1)-binding capacity of silage bacteria and factors affecting the responses. Experiments 1 and 2 examined the effects of bacterial strain and population on the AFB1-binding capacity of 10 bacteria. When applied at 106 cfu/mL to an in vitro medium, only Lactobacillus plantarum PT5B bound the AFB1 and the binding capacity was low (4%). When applied at 109 cfu/mL, all 10 bacteria bound AFB1, but L. plantarum R2014 (Lp) and EQ12, Lactobacillus buchneri R1102 (Lb), and Pediococcus acidilactici R2142 and EQ01 (Pa) had the greatest capacity (23.9 to 33%). Experiment 3 examined the AFB1-binding capacity of viable and nonviable (HCl-treated) forms of Lp, Lb, and Pa at different pH. Nonviable Lb and Lp, but not Pa, increased AFB1 binding. Binding of AFB1 was greatest at pH 2.5 and least at pH 8. As the nonviable Lb and Lp that bound AFB1 in experiment 3 would not be effective silage inoculants, experiment 4 examined effects of benign versus severe treatments (85 vs. 100°C; pH 2.5 vs. <1) on the viability of Lp, Lb, and Pa. The population of bacteria was reduced from 9 to 4 log cfu/mL by treatment with HCl at pH 2.5 and to 2 log cfu/mL by 85 or 100°C, whereas acidification at pH <1 eliminated the bacteria. Experiment 5 determined the effect of the ensiling duration and benign treatment methods [37 (viable cells) or 85°C (heated cells) or acidification with HCl at pH 2.5 (acid-treated cells)] on binding of AFB1 and silage quality during the fermentation of corn forage. Corn forage was ensiled after treatment with only deionized water (control), AFB1 (30 µg/kg of fresh forage), or a mixture of AFB1 and 109 cfu/g of each of the treated bacteria. Adding AFB1 alone to corn forage reduced the pH decline during the first 3 d of ensiling and increased or tended to increase butyric acid concentration and final pH after ensiling for 21 d. Bacterial inoculation inhibited these negative effects. The fermentation profile of silage treated with Lb and Pa did not differ from those of the control silage. In all silages treated with the toxin, the AFB1 concentration decreased linearly (from 30 to ≤0.35 µg/kg) within 3 d of ensiling. Certain silage bacteria can bind AFB1 but the efficacy depends on several factors.


Subject(s)
Aflatoxin B1/metabolism , Bacteria/metabolism , Silage/microbiology , Animals , Fermentation , Lactobacillus/metabolism , Lactobacillus plantarum/metabolism , Pediococcus acidilactici , Zea mays
17.
Phys Rev Lett ; 118(10): 101101, 2017 Mar 10.
Article in English | MEDLINE | ID: mdl-28339273

ABSTRACT

We report on a search for electronic recoil event rate modulation signatures in the XENON100 data accumulated over a period of 4 yr, from January 2010 to January 2014. A profile likelihood method, which incorporates the stability of the XENON100 detector and the known electronic recoil background model, is used to quantify the significance of periodicity in the time distribution of events. There is a weak modulation signature at a period of 431_{-14}^{+16} day in the low energy region of (2.0-5.8) keV in the single scatter event sample, with a global significance of 1.9σ; however, no other more significant modulation is observed. The significance of an annual modulation signature drops from 2.8σ, from a previous analysis of a subset of this data, to 1.8σ with all data combined. Single scatter events in the low energy region are thus used to exclude the DAMA/LIBRA annual modulation as being due to dark matter electron interactions via axial vector coupling at 5.7σ.

18.
Sci Rep ; 7: 41699, 2017 02 09.
Article in English | MEDLINE | ID: mdl-28181520

ABSTRACT

The high neutron detection efficiency, good gamma-ray discrimination and non-toxicity of 3He made of proportional counters filled with this gas the obvious choice for neutron detection, particularly in radiation portal monitors (RPM), used to control the illicit transport of nuclear material, of which neutron detectors are key components. 3He is very rare and during the last decade this gas has become increasingly difficult to acquire. With the exception of BF3, which is toxic, no other gas can be used for neutron detection in proportional counters. We present an alternative where the 3He atoms are replaced by nanoparticles made of another neutron sensitive material, 10B. The particles are dispersed in a gaseous volume, forming an aerosol with neutron sensitive properties. A proportional counter filled with such aerosol was exposed to a thermal neutron beam and the recorded response indicates that the neutrons have interacted with the particles in the aerosol. This original technique, which transforms a standard proportional gas mixture into a neutron sensitive aerosol, is a breakthrough in the field of radiation detection and has the potential to become an alternative to the use of 3He in proportional counters.

19.
Med Vet Entomol ; 28(1): 103-9, 2014 Mar.
Article in English | MEDLINE | ID: mdl-23786327

ABSTRACT

Culex (Culex) pipiens (Diptera: Culicidae) has two recognized biotypes, pipiens and molestus, which differ in physiology and behaviour; this difference may influence vectorial capacity for West Nile virus (WNV). Our goal was first to determine the presence of Cx. pipiens populations in 31 locations in Portugal and to subsequently analyse their host-feeding preferences and habitat determinants. Molecular identification of Cx. pipiens forms and their hybrids was performed in 97 females; bloodmeal sources were identified in 59 engorged specimens. Overall, 61.9% of specimens were identified as Cx. pipiens f. pipiens, 20.6% as Cx. pipiens f. molestus, and 17.5% as hybrid forms. Culex pipiens f. pipiens fed preferentially on birds, and Cx. pipiens f. molestus on humans. Hybrid forms fed mostly on birds, but human bloodmeals were common. With reference to habitat, Cx. pipiens f. pipiens and hybrid forms were positively correlated with peri-urban habitats. Our results confirm the sympatric presence of different Cx. pipiens biotypes in 14 of the 31 locations studied. Peri-urban areas were a common habitat of all biotypes and may represent zones of hybridization. The feeding preferences and sympatric distribution of the Cx. pipiens biotypes observed in Portugal favour the epizootic circulation of WNV and the occurrence of disease outbreaks of WNV.


Subject(s)
Culex/physiology , Ecosystem , Insect Vectors/physiology , Sympatry , Animals , Culex/genetics , Feeding Behavior , Female , Humans , Hybridization, Genetic , Insect Vectors/genetics , Male , Microsatellite Repeats , Polymerase Chain Reaction , Polymorphism, Genetic , Portugal , Species Specificity , West Nile Fever/transmission , West Nile Fever/virology , West Nile virus/physiology
20.
Euro Surveill ; 18(6)2013 Feb 07.
Article in English | MEDLINE | ID: mdl-23410256

ABSTRACT

An outbreak of dengue fever in Madeira island was reported in 2012. Clinical and laboratory findings of the first two laboratory-confirmed autochthonous cases are reported. Both cases had fever (≥38 °C) and petechial rash. Symptoms also included myalgia, asthenia, nausea, vomiting, anorexia, diffuse abdominal pain, and diarrhoea. The two cases were confirmed by serology and one tested positive for a dengue viral sequence. Dengue virus serotype DEN-1 was identified with probable Central or South American origin.


Subject(s)
Dengue Virus/genetics , Dengue Virus/isolation & purification , Dengue/diagnosis , Dengue/epidemiology , Disease Outbreaks , Adolescent , Adult , Aedes/virology , Animals , Clinical Laboratory Techniques , Dengue/transmission , Dengue/virology , Dengue Virus/classification , Female , Humans , Male , Phylogeny , Portugal/epidemiology , RNA, Viral/genetics , Reverse Transcriptase Polymerase Chain Reaction , Sequence Analysis , Serotyping
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