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1.
Phys Rev Lett ; 132(4): 041001, 2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-38335333

RESUMEN

With excellent energy resolution and ultralow-level radiogenic backgrounds, the high-purity germanium detectors in the Majorana Demonstrator enable searches for several classes of exotic dark matter (DM) models. In this work, we report new experimental limits on keV-scale sterile neutrino DM via the transition magnetic moment from conversion to active neutrinos ν_{s}→ν_{a}. We report new limits on fermionic dark matter absorption (χ+A→ν+A) and sub-GeV DM-nucleus 3→2 scattering (χ+χ+A→ϕ+A), and new exclusion limits for bosonic dark matter (axionlike particles and dark photons). These searches utilize the (1-100)-keV low-energy region of a 37.5-kg y exposure collected by the Demonstrator between May 2016 and November 2019 using a set of ^{76}Ge-enriched detectors whose surface exposure time was carefully controlled, resulting in extremely low levels of cosmogenic activation.

2.
Opt Lett ; 48(12): 3127-3130, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37319043

RESUMEN

Spatial coherence of light sources is usually obtained by using the classical Young's interferometer. Although the original experiment was improved upon in successive works, some drawbacks still remain. For example, several pairs of points must be used to obtain the complex coherence degree (normalized first-order correlation function) of the source. In this work, a modified Mach-Zehnder interferometer which includes a pair of lenses and is able to measure the spatial coherence degree is presented. With this modified Mach-Zehnder interferometer, it is possible to measure the full 4D spatial coherence function by displacing the incoming beam laterally. To test it, we have measured only a 2D projection (zero shear) of the 4D spatial coherence, which is enough to characterize some types of sources. The setup has no movable parts, making it robust and portable. To test it, the two-dimensional spatial coherence of a high-speed laser with two cavities was measured for different pulse energy values. We observe from the experimental measurements that the complex degree of coherence changes with the selected output energy. Both laser cavities seem to have similar complex coherence degrees for the maximum energy, although it is not symmetrical. Thus, this analysis will allow us to determine the best configuration of the double-cavity laser for interferometric applications. Furthermore, the proposed approach can be applied to any other light sources.


Asunto(s)
Rayos Láser , Lentes , Interferometría/métodos
3.
Phys Rev Lett ; 130(6): 062501, 2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36827565

RESUMEN

The Majorana Demonstrator searched for neutrinoless double-ß decay (0νßß) of ^{76}Ge using modular arrays of high-purity Ge detectors operated in vacuum cryostats in a low-background shield. The arrays operated with up to 40.4 kg of detectors (27.2 kg enriched to ∼88% in ^{76}Ge). From these measurements, the Demonstrator has accumulated 64.5 kg yr of enriched active exposure. With a world-leading energy resolution of 2.52 keV FWHM at the 2039 keV Q_{ßß} (0.12%), we set a half-life limit of 0νßß in ^{76}Ge at T_{1/2}>8.3×10^{25} yr (90% C.L.). This provides a range of upper limits on m_{ßß} of (113-269) meV (90% C.L.), depending on the choice of nuclear matrix elements.

5.
Phys Rev Lett ; 129(8): 080401, 2022 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-36053678

RESUMEN

The Majorana Demonstrator neutrinoless double-beta decay experiment comprises a 44 kg (30 kg enriched in ^{76}Ge) array of p-type, point-contact germanium detectors. With its unprecedented energy resolution and ultralow backgrounds, Majorana also searches for rare event signatures from beyond standard model physics in the low energy region below 100 keV. In this Letter, we test the continuous spontaneous localization (CSL) model, one of the mathematically well-motivated wave function collapse models aimed at solving the long-standing unresolved quantum mechanical measurement problem. While the CSL predicts the existence of a detectable radiation signature in the x-ray domain, we find no evidence of such radiation in the 19-100 keV range in a 37.5 kg-y enriched germanium exposure collected between December 31, 2015, and November 27, 2019, with the Demonstrator. We explored both the non-mass-proportional (n-m-p) and the mass-proportional (m-p) versions of the CSL with two different assumptions: that only the quasifree electrons can emit the x-ray radiation and that the nucleus can coherently emit an amplified radiation. In all cases, we set the most stringent upper limit to date for the white CSL model on the collapse rate, λ, providing a factor of 40-100 improvement in sensitivity over comparable searches. Our limit is the most stringent for large parts of the allowed parameter space. If the result is interpreted in terms of the Diòsi-Penrose gravitational wave function collapse model, the lower bound with a 95% confidence level is almost an order of magnitude improvement over the previous best limit.

6.
Phys Rev Lett ; 129(8): 081803, 2022 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-36053699

RESUMEN

Axions were originally proposed to explain the strong-CP problem in QCD. Through axion-photon coupling, the Sun could be a major source of axions, which could be measured in solid state detection experiments with enhancements due to coherent Primakoff-Bragg scattering. The Majorana Demonstrator experiment has searched for solar axions with a set of ^{76}Ge-enriched high purity germanium detectors using a 33 kg-yr exposure collected between January, 2017 and November, 2019. A temporal-energy analysis gives a new limit on the axion-photon coupling as g_{aγ}<1.45×10^{-9} GeV^{-1} (95% confidence level) for axions with mass up to 100 eV/c^{2}. This improves laboratory-based limits between about 1 eV/c^{2} and 100 eV/c^{2}.

7.
J Dairy Sci ; 105(12): 9896-9916, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36241433

RESUMEN

The objectives were to investigate whether supplementation with rumen-protected choline (RPC) during late pregnancy in Holstein cows affects offspring immunity and growth, and whether effects are utero-placental, colostrum dependent, or both. A total of 105 multiparous Holstein cows were assigned randomly to a prepartum diet (1.54 Mcal of NEL/kg of DM, and 15.8% CP) without (control) or with added RPC (12.9 g/d of choline ion). Calves (n = 111) were blocked by sex and assigned randomly to colostrum from control cows or colostrum from RPC cows, resulting in 4 treatments in a 2 × 2 factorial arrangement: (1) calves born and fed colostrum from non-supplemented dams (NN; n = 33); (2) calves from non-supplemented dams and fed colostrum from RPC-fed cows (NC; n = 25); (3) calves from RPC-supplemented dams and colostrum from non-supplemented cows (CN; n = 28); and (4) calves from RPC-supplemented dams and colostrum from RPC-fed cows (CC; n = 25). Growth, intakes, and immunity of females were evaluated up to 56 d of age. Growth and intake of male calves was evaluated up to 35 d of age, and physiological and immune responses to intravenous LPS challenge were evaluated from 21 to 35 d of age. Effects of prenatal and colostrum treatments and interactions between treatments were analyzed using mixed models. Calves fed colostrum from RPC-supplemented dams had a 17.4% increase in apparent efficiency of absorption of IgG compared with calves fed colostrum from control dams (27.4 vs. 23.3%). Incidence of fever in the first 21 d of age tended to be less in females born from RPC-supplemented dams compared with females born from control dams (31 vs. 58%). Prenatal RPC females had increased hematocrit and concentrations of red blood cells, leukocytes, neutrophils, and lymphocytes in blood compared with prenatal females born from control dams. Compared with prenatal control females, prenatal RPC females had greater intake of milk replacer (704 vs. 748 ± 9.9 g/d) and starter (45.4 vs. 60.2 ± 5.9 g/d) during the first 21 d of age. In male calves, mean intake of DM was greater (1,074 vs. 976 ± 45 g/d) after the LPS challenge (0 to 8 d) by calves born from dams fed RPC compared with males born from control dams. Calves born from RPC-fed dams also had lower mean rectal temperature (39.0 vs. 39.2°C) and mean respiration rate (35.6 vs. 39.3 breaths/min) compared with males born from control dams. Moreover, serum concentrations of metabolites (i.e., ß-hydroxybutyric acid, fatty acids, and glucose), cytokines (i.e., tumor necrosis factor-α) and acute phase proteins (i.e., serum amyloid A) were consistent with less-severe inflammatory response to LPS in males born from dams fed RPC compared with control. Source of colostrum and interaction between prenatal and colostrum treatments had minimal effects on calf responses to LPS. Overall, maternal RPC supplementation during late gestation suggests a positive effect on immunity, in that colostrum from RPC-fed dams increased efficiency of IgG absorption and maternal supplementation with RPC during late gestation, regardless of colostrum source, attenuated responses to LPS.


Asunto(s)
Lipopolisacáridos , Placenta , Bovinos , Animales , Embarazo , Masculino , Femenino , Destete , Calostro , Dieta/veterinaria , Suplementos Dietéticos , Colina/farmacología , Inmunoglobulina G , Alimentación Animal/análisis , Animales Recién Nacidos
8.
J Dairy Sci ; 103(5): 4174-4191, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32171515

RESUMEN

Objectives were to evaluate the effects of altering timing of initiating and duration of supplementing rumen-protected choline (RPC) on lactation performance in dairy cows. The hypothesis was that RPC increases yields of milk and milk components, regardless of when supplementation is initiated, and that the effects of supplementing RPC starting prepartum and continuing post-transition would be additive. Cows at 241 ± 2.2 d of gestation were blocked by parity group (49 entering lactation 2, 50 entering lactation >2) and 305-d milk yield and, within block, assigned randomly to 1 of 4 treatments arranged as a 2 × 2 factorial with 2 levels of choline in transition, from 21 d pre- to 21 d postpartum, and 2 levels of choline in post-transition, from 22 to 105 d postpartum. The 2 levels of RPC supplemented were either 0 g/d or 12.9 g/d of choline ion fed as 60 g/d of an RPC product that was top-dressed onto the total mixed ration. Thus, treatments were as follows: NN (n = 25): no choline in transition or post-transition; NC (n = 25): no choline in transition and choline in post-transition; CN (n = 25): choline in transition and no choline in post-transition; CC (n = 24): choline in transition and in post-transition. Prepartum, treatments were supplemented (mean ± SD) for the last 18.8 ± 5.7 and 19.2 ± 5.0 d of gestation in treatments with 0 or 12.9 g/d of choline ion, respectively. Supplementing RPC prepartum did not affect dry matter intake (DMI), body weight (BW), or body condition score (BCS) in the last 3 weeks of gestation. Likewise, RPC did not affect the yield or the composition of colostrum. Supplementation with RPC during transition increased fat percent by 0.02 percentage units, fat yield by 0.16 kg/d, and energy-corrected milk (ECM) by 3.1 kg/d in the first 21 d postpartum, and increased fat yield by 0.10 kg/d and ECM by 2.4 kg/d from 22 to 105 d postpartum. Supplementing RPC during transition did not affect DMI postpartum, but it improved feed efficiency, and cows produced 0.11 kg/d more ECM per kg of DMI. Changes in BW and BCS during the first 21 d postpartum did not differ between treatments. Cows fed RPC during transition had more negative net energy balance and 0.1 unit smaller BCS in the first 105 d postpartum than non-supplemented cows. Supplementing RPC in post-transition did not influence productive performance in dairy cows, and choline supplementation during transition or post-transition did not affect measures of reproduction. Collectively, supplementing RPC to supply 12.9 g/d of choline ion benefited productive performance in dairy cows when supplementation occurred during the transition period, but no additional benefit was observed from supplementing RPC past 22 d postpartum.


Asunto(s)
Bovinos , Colina/farmacología , Dieta/veterinaria , Lactancia , Animales , Peso Corporal , Colina/administración & dosificación , Industria Lechera , Suplementos Dietéticos , Metabolismo Energético , Femenino , Lactancia/efectos de los fármacos , Leche , Periodo Posparto , Rumen/metabolismo
9.
J Dairy Sci ; 103(5): 4192-4205, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31785869

RESUMEN

The objectives of this study were to evaluate the effects of rumen-protected choline (RPC) supplementation from 21 d pre- to 21 d postpartum on markers of metabolic status and inflammatory response, concentrations of liposoluble vitamins, and plasma total Ca in parous Holstein cows. The hypotheses were that supplementing RPC during the transition period would reduce hepatic triacylglycerol accumulation postpartum and attenuate markers of inflammatory response following parturition, and collectively, such responses were expected to benefit health of dairy cows. Parous cows at 241 d of gestation were blocked by parity group and 305-d milk yield, and within block, they were assigned randomly to receive either 0 g/d [no choline in transition (NT), n = 55] or 12.9 g/d choline ion [choline in transition (CT), n = 58] from 21 d pre- to 21 postpartum. The RPC product was individually top-dressed onto the total mixed ration once daily. Prepartum, treatments were supplemented (mean ± standard deviation) for the last 18.8 ± 5.7 and 19.2 ± 5.0 d of gestation in NT and CT, respectively. Supplementing RPC prepartum did not affect concentrations of plasma metabolites and inflammatory markers during the last 3 wk of gestation. Postpartum, cows fed RPC had greater hepatic concentration of hepatic triacylglycerol (NT = 3.4 vs. CT = 4.4%) and tended to have increased concentration of ß-hydroxybutyrate (NT = 0.48 vs. CT = 0.53 mM) in plasma. In spite of the increased hepatic triacylglycerol in cows fed RPC, treatment did not affect the concentrations of the inflammatory marker tumor necrosis factor-α or of the positive acute phase proteins, haptoglobin and fibrinogen. Supplementing choline tended to increase the concentration of plasma triacylglycerol by 0.69 mg/dL in the first 21 d postpartum and reduced the incidence of subclinical hypocalcemia by 20.9 percentage units compared with NT. Supplementing transition cows with RPC did not affect the concentrations of liposoluble vitamins in the first 7 d postpartum or the incidence of individual diseases or morbidity in early lactation. The inability of supplemental choline to reduce hepatic triacylglycerol might have been a consequence of the increased productive performance without additional dry matter intake.


Asunto(s)
Enfermedades de los Bovinos/prevención & control , Colina/farmacología , Dieta/veterinaria , Suplementos Dietéticos , Inflamación/veterinaria , Ácido 3-Hidroxibutírico/sangre , Animales , Bovinos , Colina/administración & dosificación , Femenino , Estado de Salud , Inflamación/prevención & control , Lactancia , Hígado/metabolismo , Leche , Paridad , Periodo Posparto/metabolismo , Embarazo , Rumen/metabolismo , Triglicéridos/metabolismo , Vitaminas/metabolismo
10.
J Intellect Disabil Res ; 64(8): 612-628, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32573859

RESUMEN

BACKGROUND: People with intellectual disabilities (IDs) seem to have a lower physical fitness (PF) than their peers without disabilities, which coincides with reduced autonomy, life expectancy and quality of life. To assess PF in these individuals, it is necessary to use appropriate tools that permit the assessment of their physical capacities taking into account their specific characteristics. The aim of this work is to study the feasibility and reliability of the Assessing Levels of Physical Activity (ALPHA)-Fit test battery for adults in a group of men and women with mild to moderate ID. METHODS: Forty-one adults with ID of both sexes, ranging in age from 20 to 60 years old, participated in the study. To identify the feasibility and reliability of the ALPHA-Fit test battery for adults, two complete assessments were done for each one of the tests included in the battery. The assessments were performed for a period of no more than 2 weeks (test-retest). An intraclass correlation coefficient was used to determinate test-retest reliability, and a mixed analysis of variance factorial was used for each of the dependent variables. Bland-Altman plots were also used to assess consistency between the two measurements. Feasibility was calculated as the percentage of people who were able to perform the tests correctly (not feasible <50%, fairly feasible 50%-75% and feasible >75%). In order to determine other psychometric properties, minimal detectable change and standard error of measurement (SEM) were also calculated. RESULTS: Of the 10 tests in the ALPHA-Fit test battery, eight were shown to be feasible. High reliability was obtained (>0.90) for the variables related to body composition. In the hand-grip test, reliability was high in the men's group but low in the women's group. Good reliability results were also found (0.80-0.89) in the dynamic sit-up test for women, but not for men. Fair reliability (0.70-0.79) was found in jump-and-reach and neck-shoulder mobility tests. The variables in the 2-km walk and agility tests indicated poor reliability. All tests showed SEM values related to high variability. However, Bland-Altman plots showed results related to lack of consistency. CONCLUSIONS: The feasibility and reliability calculations, as well as the SEM values, confirm that not all the tests of the ALPHA-Fit Test Battery for Adults are suitable for the assessment of PF in adults with ID, probably because of the complexity of the motor fitness tests. The authors emphasise the necessity of making adaptations to the protocols used or of using other tests more appropriate to the characteristics of people with mild to moderate ID.


Asunto(s)
Prueba de Esfuerzo/normas , Ejercicio Físico/fisiología , Discapacidad Intelectual/fisiopatología , Aptitud Física/fisiología , Psicometría/normas , Adulto , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Adulto Joven
11.
Med Oral Patol Oral Cir Bucal ; 25(2): e195-e204, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31967985

RESUMEN

BACKGROUND: The main objective of this study was to estimate the prevalence of human papillomavirus-DNA (HPV-DNA) in the saliva of sexually active women with HPV-related cervical intraepithelial neoplasias (CIN) and compare the findings with a healthy control group. The secondary objectives were: 1) to determine the concordance between genital and oral HPV types in sexually active women with HPV-related CIN; 2) to analyze whether sexual habits influence the presence of HPV-related CIN; 3) to determine whether sexual habits influence the presence of oral HPV. MATERIAL AND METHODS: Saliva samples were collected from 100 sexually active women, 50 with HPV-related CIN and 50 healthy subjects presenting normal cytology. PCR assay was used to detect HPV-DNA. RESULTS: The prevalence of oral HPV infection in saliva samples was 14% in women with HPV-related CIN, while in the healthy group it was 12%, without statistically significant difference (p=0.766). As for the concordance between genital and oral HPV types in women with HPV-related CIN, concordance was only observed for HPV-16, whereby among 22 women with genital HPV-16, only one (4.54%) also presented oral HPV-16. Regarding the possible influence of sexual habits on the presence of cervical pathology and presence of oral HPV, it was found that marital status, age at first intercourse, number of lifetime sexual partners, and condom use are related with the presence of cervical pathology (p<0.001; p=0.017; p=0.002; and p<0.001, respectively); condom use was also found to be related to the presence of oral HPV (p<0.001). CONCLUSIONS: The prevalence of HPV-DNA in the saliva of sexually active women with HPV-related CIN is similar to healthy women. The concordance between genital and oral HPV types is low. Both the presence of cervical pathology and the presence of oral HPV are related to sexual habits. Wider sample size is required to confirm this results.


Asunto(s)
Papillomaviridae , Infecciones por Papillomavirus , Displasia del Cuello del Útero , Neoplasias del Cuello Uterino , Femenino , Humanos , Prevalencia , Factores de Riesgo , Saliva
12.
Anaesthesia ; 74(1): 22-28, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30288741

RESUMEN

Cricoid force is widely applied to decrease the risk of pulmonary aspiration and gastric antral insufflation of air during positive-pressure ventilation, yet its efficacy remains controversial. We compared manual oesophageal compression at the low left paratracheal and cricoid levels for the prevention of gastric antral air insufflation during positive-pressure ventilation by facemask in patients scheduled for elective surgery under general anaesthesia. After gaining written consent, participants were randomly allocated by sealed envelope to one of three groups: oesophageal compression by 30 N paratracheal force (paratracheal group); oesophageal compression by 30 N cricoid force (cricoid group); or no oesophageal compression (control group). Gastric insufflation of air was assessed before and after positive-pressure ventilation by ultrasound measurement of the antral cross-sectional area and/or presence of air artefacts in the antrum. The primary outcome measure was the proportion of participants with ultrasound evidence of gastric insufflation. We recruited 30 patients into each group. Before facemask ventilation, no air artefacts were visible in the antrum in any of the participants. After facemask ventilation of the participant's lungs, no air artefacts were seen in the paratracheal group, compared with six subjects in the cricoid group and eight subjects in the control group (p = 0.012). Our results suggest that oesophageal compression can be achieved by the application of manual force at the low left paratracheal level and that this is more effective than cricoid force in preventing air entry into the gastric antrum during positive-pressure ventilation by facemask.


Asunto(s)
Esófago/fisiología , Insuflación/métodos , Respiración con Presión Positiva , Antro Pilórico , Adolescente , Adulto , Anciano , Anestesia General , Cartílago Cricoides/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Presión , Antro Pilórico/diagnóstico por imagen , Ultrasonografía , Adulto Joven
13.
Clin Exp Immunol ; 191(2): 229-239, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28963724

RESUMEN

Itolizumab is a humanized anti-CD6 monoclonal antibody (mAb) that has previously shown encouraging results, in terms of safety and positive clinical effects, in a 6-week monotherapy clinical trial conducted in rheumatoid arthritis (RA) patients. The current Phase I study evaluated the safety and clinical response for a longer treatment of 12 itolizumab intravenous doses in subjects with active RA despite previous disease-modifying anti-rheumatic drug (DMARD) therapy. Twenty-one subjects were enrolled into four dosage groups (0·1, 0·2, 0·4 and 0·8 mg/kg). Efficacy end-points including American College of Rheumatology (ACR)20, ACR50 and ACR70 response rates and disease activity score in 28 joints (DAS28) were monitored at baseline and at specific time-points during a 10-week follow-up period. Itolizumab was well tolerated up to the highest tested dose. No related serious adverse events were reported and most adverse events were mild. Remarkably, itolizumab treatment did not produce lymphopenia and, therefore, was not associated with infections. All patients achieved a clinical response (ACR20) at least once during the study. Eleven subjects (55%) achieved at least a 20% improvement in ACR just 1 week after the first itolizumab administration. The clinical response was observed from the beginning of the treatment and was sustained during 24 weeks. The efficacy profile of this 12-week treatment was similar to that of the previous study (6-week treatment). These results reinforce the safety profile of itolizumab and provide further evidence on the clinical benefit from the use of this anti-CD6 mAb in RA patients.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Adolescente , Adulto , Anciano , Antígenos CD/inmunología , Antígenos de Diferenciación de Linfocitos T/inmunología , Cuba , Progresión de la Enfermedad , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Femenino , Estudios de Seguimiento , Humanos , Linfopenia , Masculino , Persona de Mediana Edad , Adulto Joven
14.
Phys Rev Lett ; 120(21): 211804, 2018 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-29883176

RESUMEN

The Majorana Demonstrator is an ultralow-background experiment searching for neutrinoless double-beta decay in ^{76}Ge. The heavily shielded array of germanium detectors, placed nearly a mile underground at the Sanford Underground Research Facility in Lead, South Dakota, also allows searches for new exotic physics. Free, relativistic, lightly ionizing particles with an electrical charge less than e are forbidden by the standard model but predicted by some of its extensions. If such particles exist, they might be detected in the Majorana Demonstrator by searching for multiple-detector events with individual-detector energy depositions down to 1 keV. This search is background-free, and no candidate events have been found in 285 days of data taking. New direct-detection limits are set for the flux of lightly ionizing particles for charges as low as e/1000.

15.
Phys Rev Lett ; 118(16): 161801, 2017 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-28474933

RESUMEN

We present new limits on exotic keV-scale physics based on 478 kg d of Majorana Demonstrator commissioning data. Constraints at the 90% confidence level are derived on bosonic dark matter (DM) and solar axion couplings, Pauli exclusion principle violating (PEPV) decay, and electron decay using monoenergetic peak signal limits above our background. Our most stringent DM constraints are set for 11.8 keV mass particles, limiting g_{Ae}<4.5×10^{-13} for pseudoscalars and (α^{'}/α)<9.7×10^{-28} for vectors. We also report a 14.4 keV solar axion coupling limit of g_{AN}^{eff}×g_{Ae}<3.8×10^{-17}, a 1/2ß^{2}<8.5×10^{-48} limit on the strength of PEPV electron transitions, and a lower limit on the electron lifetime of τ_{e}>1.2×10^{24} yr for e^{-}→ invisible.

16.
Parasitol Res ; 114(11): 4327-31, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26341796

RESUMEN

Eimeria ninakohlyakimovae is an important coccidian parasite of goats which causes severe diarrhoea in young animals. Specific molecules that mediate E. ninakohlyakimovae host interactions and molecular mechanisms involved in the pathogenesis are still unknown. Although strong circumstantial evidence indicates that E. ninakohlyakimovae sporozoite interactions with caprine endothelial host cells (ECs) are specific, hardly any information is available about the interacting molecules that confer host cell specificity. In this study, we describe a novel method to identify surface proteins of caprine umbilical vein endothelial cells (CUVEC) using a phage display library. After several panning rounds, we identified a number of peptides that specifically bind to the surface of CUVEC. Importantly, caprine endothelial cell peptide 2 (PCEC2) and PCEC5 selectively reduced the infection rate by E. ninakohlyakimovae sporozoites. These preliminary data give new insight for the molecular identification of ligands involved in the interaction between E. ninakohlyakimovae sporozoites and host ECs. Further studies using this phage approach might be useful to identify new potential target molecules for the development of anti-coccidial drugs or even new vaccine strategies.


Asunto(s)
Coccidiosis/veterinaria , Eimeria/fisiología , Células Endoteliales/inmunología , Enfermedades de las Cabras/inmunología , Biblioteca de Péptidos , Péptidos/inmunología , Animales , Coccidiosis/genética , Coccidiosis/inmunología , Coccidiosis/parasitología , Eimeria/crecimiento & desarrollo , Células Endoteliales/parasitología , Enfermedades de las Cabras/genética , Enfermedades de las Cabras/parasitología , Cabras , Interacciones Huésped-Parásitos , Ligandos , Péptidos/genética , Esporozoítos/crecimiento & desarrollo , Esporozoítos/fisiología
17.
Phys Rev Lett ; 113(26): 267205, 2014 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-25615381

RESUMEN

After nearly 20 years of study, the origin of the spin-liquid state in Tb2Ti2O7 remains a challenge for experimentalists and theorists alike. To improve our understanding of the exotic magnetism in Tb2Ti2O7, we synthesize a chemical pressure analog: Tb2Ge2O7. Substitution of titanium by germanium results in a lattice contraction and enhanced exchange interactions. We characterize the magnetic ground state of Tb2Ge2O7 with specific heat, ac and dc magnetic susceptibility, and polarized neutron scattering measurements. Akin to Tb2Ti2O7, there is no long-range order in Tb2Ge2O7 down to 20 mK. The Weiss temperature of -19.2(1) K, which is more negative than that of Tb2Ti2O7, supports the picture of stronger antiferromagnetic exchange. Polarized neutron scattering of Tb2Ge2O7 reveals that liquidlike correlations dominate in this system at 3.5 K. However, below 1 K, the liquidlike correlations give way to intense short-range ferromagnetic correlations with a length scale similar to the Tb-Tb nearest neighbor distance. Despite stronger antiferromagnetic exchange, the ground state of Tb2Ge2O7 has ferromagnetic character, in stark contrast to the pressure-induced antiferromagnetic order observed in Tb2Ti2O7.

18.
Ann Hematol ; 93(9): 1551-8, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24782117

RESUMEN

Patients with mantle cell lymphoma (MCL) have an adverse outcome after relapse. Bendamustine has demonstrated a good efficacy and toxicity profile in previously reported trials. In this study, we present a retrospective analysis of the Spanish experience in relapsed/refractory MCL treated with bendamustine in combination or alone with the objective of knowing the efficacy and toxicity profile of this treatment in our current clinical practice. Fifty eight patients were registered: 67 % male with median age of 71 years, and 2 is the median number of previous lines. The most frequent bendamustine regimen was bendamustine plus rituximab (83 %). The median number of cycles was 5 (range 1-8). The overall response rate was 84 % with 53 % of complete response/unconfirmed complete response (CR/uCR). Median progression-free survival (PFS) was 16 months (95 % confidence interval (CI) 13.3-18.8), and for patients who achieved CR/uCR, it was 33 months (95 % CI 11.1-54.2). Median overall survival (OS) was 30 months (95 % CI 25.6-34.9). For PFS, only blastoid histology and not achieving CR after bendamustine had a significant negative impact on the univariate and multivariate analyses (p < 0.05). Nevertheless, for OS, only an elevated lactate dehydrogenase (LDH) had negative impact on both, univariate and multivariate analyses (p < 0.05). Only one case of treatment-related mortality in a 79-year-old patient with very bad performance status was reported. In 280 cycles, 12 (4 %) hospitalizations for febrile neutropenia were reported. In our population, bendamustine has been a good salvage treatment with a favorable toxicity profile in a non selected and heavily pretreated population of patients with MCL.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Linfoma de Células del Manto/tratamiento farmacológico , Compuestos de Mostaza Nitrogenada/uso terapéutico , Terapia Recuperativa , Adulto , Anciano , Anciano de 80 o más Años , Clorhidrato de Bendamustina , Resistencia a Antineoplásicos/efectos de los fármacos , Femenino , Humanos , Linfoma de Células del Manto/epidemiología , Linfoma de Células del Manto/patología , Masculino , Persona de Mediana Edad , Recurrencia , Estudios Retrospectivos , España/epidemiología , Insuficiencia del Tratamiento
19.
J Biomed Inform ; 51: 176-90, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24909817

RESUMEN

This study presents a Web platform (http://3dfd.ujaen.es) for computing and analyzing the 3D fractal dimension (3DFD) from volumetric data in an efficient, visual and interactive way. The Web platform is specially designed for working with magnetic resonance images (MRIs) of the brain. The program estimates the 3DFD by calculating the 3D box-counting of the entire volume of the brain, and also of its 3D skeleton. All of this is done in a graphical, fast and optimized way by using novel technologies like CUDA and WebGL. The usefulness of the Web platform presented is demonstrated by its application in a case study where an analysis and characterization of groups of 3D MR images is performed for three neurodegenerative diseases: Multiple Sclerosis, Intrauterine Growth Restriction and Alzheimer's disease. To the best of our knowledge, this is the first Web platform that allows the users to calculate, visualize, analyze and compare the 3DFD from MRI images in the cloud.


Asunto(s)
Encefalopatías/patología , Encéfalo/patología , Imagenología Tridimensional/métodos , Internet , Reconocimiento de Normas Patrones Automatizadas/métodos , Programas Informáticos , Interfaz Usuario-Computador , Algoritmos , Fractales , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
20.
Genet Mol Res ; 13(3): 7673-85, 2014 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-25299081

RESUMEN

The genus Colletotrichum, comprised of pathogenic fungi that affect plants grown worldwide, causes the disease known as anthracnose in several fruit and vegetable species. Several studies conducted on plants have shown that the disease is characterized by the presence of one or several species of the fungus attacking the fruit or other organs of the same host. To develop and implement effective control strategies, it is vital to understand the genetic structure of the fungus in agricultural systems, identify associated Colletotrichum species, and define the subpopulations responsible for the disease. Molecular tools were accordingly developed to characterize genotypic populations of Colletotrichum spp, causal agent of anthracnose in commercial crops of Andean blackberry (Rubus glaucus Benth.). A microsatellite-enriched library for Colletotrichum gloeosporioides was developed to identify and characterize microsatellite loci among isolates collected in R. glaucus plantations. Thirty microsatellites were developed and tested in 36 isolates gathered from eight different blackberry-production areas of Colombia. Ten pairs of microsatellites were polymorphic.


Asunto(s)
Colletotrichum/aislamiento & purificación , Repeticiones de Microsatélite/genética , Micosis/microbiología , Rubus/microbiología , Secuencia de Bases , Colletotrichum/genética , Cartilla de ADN , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
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