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1.
Phys Rev Lett ; 130(12): 122502, 2023 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-37027859

RESUMEN

The excited states of N=44 ^{74}Zn were investigated via γ-ray spectroscopy following ^{74}Cu ß decay. By exploiting γ-γ angular correlation analysis, the 2_{2}^{+}, 3_{1}^{+}, 0_{2}^{+}, and 2_{3}^{+} states in ^{74}Zn were firmly established. The γ-ray branching and E2/M1 mixing ratios for transitions deexciting the 2_{2}^{+}, 3_{1}^{+}, and 2_{3}^{+} states were measured, allowing for the extraction of relative B(E2) values. In particular, the 2_{3}^{+}→0_{2}^{+} and 2_{3}^{+}→4_{1}^{+} transitions were observed for the first time. The results show excellent agreement with new microscopic large-scale shell-model calculations, and are discussed in terms of underlying shapes, as well as the role of neutron excitations across the N=40 gap. Enhanced axial shape asymmetry (triaxiality) is suggested to characterize ^{74}Zn in its ground state. Furthermore, an excited K=0 band with a significantly larger softness in its shape is identified. A shore of the N=40 "island of inversion" appears to manifest above Z=26, previously thought as its northern limit in the chart of the nuclides.

2.
J Dairy Sci ; 106(10): 7220-7239, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37641306

RESUMEN

The benefits of feeding calves more milk are increasingly being recognized by dairy farmers. However, most producers have still not implemented higher feeding plans. The aim of the present study was to gain a deeper understanding of farmer and farm staff attitudes, and the perceptions and factors considered in their decision-making regarding daily milk allowances. We collected data through focus group interviews with dairy farmers, farm managers, and calf-care workers who were selected using purposive and snowball sampling. In total, 40 persons (24 women and 16 men) joined a focus group interview (6 in all, each with 5-8 participants). Interviews were recorded, and recordings were transcribed and analyzed thematically. Participants had contrasting opinions about the minimum, maximum, and recommended daily milk allowances to their calves. Their suggested lowest daily milk allowance to sustain animal welfare ranged from 4 to 8-10 L and the maximum allowance from 6 to 15 L. We found that farmers' and farm staff's choices and recommendations of milk-feeding protocols were influenced by a large number of factors that could be grouped into 4 themes: (1) Life beyond work, (2) Farm facilities and equipment, (3) Care of the calves, and (4) Profitability and production. Participants' considerations were similar and aimed to maximize daily milk allowance based on farm conditions. However, the allowances they described as optimal for their calves often differed from what they considered practically feasible. We found that the care of the calves and the well-being of the owners and the staff was central in the participants' decision-making, but that this care perspective was challenged by the social and economic sustainability of the farm. Most participants fed their calves twice daily and did not think that increasing that number would be practically feasible. Our results indicate that the participants' viewpoints regarding calves were important for their decision-making about milk allowances. We suggest that a more holistic perspective should be used when advising farmers about milk allowances, putting particular emphasis on the caring and social sustainability aspects of the individual farm.


Asunto(s)
Agricultores , Leche , Masculino , Animales , Bovinos , Femenino , Humanos , Granjas , Actitud del Personal de Salud , Bienestar del Animal
3.
J Dairy Sci ; 105(8): 6820-6832, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35688734

RESUMEN

Cattle veterinarians have long been encouraged to take on a role as proactive health consultants. However, the process so far has been slow in Sweden and elsewhere, and only a rather small proportion of cattle work conducted by veterinarians involves veterinary herd health management (VHHM). The aims of this exploratory study were to explore Swedish cattle veterinarians' interpretation of VHHM services and to understand the factors that might affect the extent to which cattle veterinarians perform VHHM. Six focus group discussions with cattle veterinarians complemented with 5 individual telephone interviews with clinic managers were conducted in 2020. In total, 33 cattle veterinarians participated, all employed by the largest employer of Swedish cattle veterinarians: Distriktsveterinärerna (Swedish Board of Agriculture). Participants were chosen from 6 geographical regions with the aim to present variations in gender, age, country of education, proportion of dairy cattle work at the clinic, experience in the veterinary profession, and experience in work with dairy herds and in VHHM. The focus group discussions and interviews were recorded and these recordings were transcribed and analyzed thematically. Participants interpreted VHHM as work associated with the process of advising and included both ad hoc advising and more strategic forms of services. Prebooked visits per se were not seen as VHHM. We identified 4 different themes among the factors affecting the extent of VHHM services: (1) farmer trust and demand; (2) veterinary competence; (3) time available for VHHM; and (4) the individual veterinarian's commitment and motivation. To gain farmers' trust and to create a demand for VHHM services, the results of VHHM work and the veterinarian's competence were deemed central by the participants. The veterinarians' skills in communication and relation building were considered especially important. Some farmers were perceived as having little interest in, or lacking deeper knowledge about, VHHM services. The promotion of VHHM services was mentioned as an important factor to increase farmer demand. Participants described VHHM as work demanding high skills and continuous capacity development. Veterinarians' personal commitment and motivation were also described as important for the extent to which VHHM services were performed. This was in turn affected by the psychosocial work environment (e.g., workload, interest and recognition from farmers and managers, and acceptance, priority, and support by colleagues and managers). Clinic managers had a central role in the extent to which VHHM services are offered by an individual veterinarian due to their responsibility for staff scheduling, which highly affects the conditions for capacity development, intercollegiate networking, and cooperation. Lack of time was a major barrier for VHHM. On-call duty time and subsequent compensatory leave affected the total time available, and participants described time conflicts between VHHM and emergency services; moreover, it was perceived as challenging to find sufficient time for capacity development in several different species for veterinarians working in mixed practice. The slow development toward more proactive approaches for cattle veterinarians can be explained by the numerous different factors that together constrain the veterinarian to the traditional role of diagnosing and treating sick animals.


Asunto(s)
Veterinarios , Animales , Bovinos , Industria Lechera/métodos , Agricultores/psicología , Humanos , Registros/veterinaria , Suecia , Veterinarios/psicología
4.
Phys Rev Lett ; 127(11): 112701, 2021 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-34558922

RESUMEN

We have performed the first direct measurement of the ^{83}Rb(p,γ) radiative capture reaction cross section in inverse kinematics using a radioactive beam of ^{83}Rb at incident energies of 2.4 and 2.7A MeV. The measured cross section at an effective relative kinetic energy of E_{cm}=2.393 MeV, which lies within the relevant energy window for core collapse supernovae, is smaller than the prediction of statistical model calculations. This leads to the abundance of ^{84}Sr produced in the astrophysical p process being higher than previously calculated. Moreover, the discrepancy of the present data with theoretical predictions indicates that further experimental investigation of p-process reactions involving unstable projectiles is clearly warranted.

5.
Phys Rev Lett ; 125(17): 172501, 2020 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-33156683

RESUMEN

The ^{80}Ge structure was investigated in a high-statistics ß-decay experiment of ^{80}Ga using the GRIFFIN spectrometer at TRIUMF-ISAC through γ, ß-e, e-γ, and γ-γ spectroscopy. No evidence was found for the recently reported 0_{2}^{+} 639-keV level suggested as evidence for low-energy shape coexistence in ^{80}Ge. Large-scale shell model calculations performed in ^{78,80,82}Ge place the 0_{2}^{+} level in ^{80}Ge at 2 MeV. The new experimental evidence combined with shell model predictions indicate that low-energy shape coexistence is not present in ^{80}Ge.

7.
Phys Rev Lett ; 123(8): 082501, 2019 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-31491233

RESUMEN

The elusive ß^{-}p^{+} decay was observed in ^{11}Be by directly measuring the emitted protons and their energy distribution for the first time with the prototype Active Target Time Projection Chamber in an experiment performed at ISAC-TRIUMF. The measured ß^{-}p^{+} branching ratio is orders of magnitude larger than any previous theoretical model predicted. This can be explained by the presence of a narrow resonance in ^{11}B above the proton separation energy.

8.
Phys Rev Lett ; 123(14): 142502, 2019 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-31702191

RESUMEN

From detailed spectroscopy of ^{110}Cd and ^{112}Cd following the ß^{+}/electron-capture decay of ^{110,112}In and the ß^{-} decay of ^{112}Ag, very weak decay branches from nonyrast states are observed. The transition rates determined from the measured branching ratios and level lifetimes obtained with the Doppler-shift attenuation method following inelastic neutron scattering reveal collective enhancements that are suggestive of a series of rotational bands. In ^{110}Cd, a γ band built on the shape-coexisting intruder configuration is suggested. For ^{112}Cd, the 2^{+} and 3^{+} intruder γ-band members are suggested, the 0_{3}^{+} band is extended to spin 4^{+}, and the 0_{4}^{+} band is identified. The results are interpreted using beyond-mean-field calculations employing the symmetry conserving configuration mixing method with the Gogny D1S energy density functional and with the suggestion that the Cd isotopes exhibit multiple shape coexistence.

9.
Acta Psychiatr Scand ; 139(1): 26-36, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30374965

RESUMEN

OBJECTIVE: Treatment with most antipsychotics is associated with an increased risk of weight gain and metabolic disturbances. In a randomized trial, we previously demonstrated that 16 weeks of glucagon-like peptide-1 receptor agonist liraglutide treatment vs. placebo significantly reduced glucometabolic disturbances and body weight in prediabetic, overweight/obese schizophrenia-spectrum disorder patients treated with clozapine or olanzapine. The aim of this study was to investigate whether the beneficial effects of the 16-week intervention were sustained beyond the intervention period. METHOD: One year after completion of the intervention, we investigated changes in body weight, fasting glucose, glycated hemoglobin, C-peptide, and lipids comparing 1-year follow-up levels to end of treatment (week 16) and baseline (week 0) levels. RESULTS: From end of treatment to the 1-year follow-up, body weight had increased in the liraglutide-treated group. However, compared to baseline levels, the placebo-subtracted body weight loss remained significantly reduced (-3.8 kg, 95% CI: -7.3 to -0.2, P = 0.04). Fasting glucose, glycated hemoglobin, C-peptide, and lipids had each returned to baseline levels 1 year after stopping liraglutide. CONCLUSION: The body weight reduction during 16 weeks of liraglutide treatment was partially sustained 1 year after the intervention was completed. However, the improvements in other metabolic parameters returned to baseline levels.


Asunto(s)
Hipoglucemiantes/farmacología , Liraglutida/farmacología , Obesidad/tratamiento farmacológico , Sobrepeso/tratamiento farmacológico , Estado Prediabético/tratamiento farmacológico , Adolescente , Adulto , Anciano , Antipsicóticos/efectos adversos , Antipsicóticos/uso terapéutico , Glucemia/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Péptido C/efectos de los fármacos , Clozapina/efectos adversos , Clozapina/uso terapéutico , Dinamarca/epidemiología , Ayuno , Femenino , Estudios de Seguimiento , Receptor del Péptido 1 Similar al Glucagón/agonistas , Hemoglobina Glucada/efectos de los fármacos , Humanos , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/uso terapéutico , Metabolismo de los Lípidos/efectos de los fármacos , Liraglutida/administración & dosificación , Liraglutida/uso terapéutico , Masculino , Persona de Mediana Edad , Obesidad/inducido químicamente , Obesidad/epidemiología , Olanzapina/efectos adversos , Olanzapina/uso terapéutico , Sobrepeso/inducido químicamente , Sobrepeso/epidemiología , Placebos/administración & dosificación , Estado Prediabético/inducido químicamente , Estado Prediabético/epidemiología , Esquizofrenia/sangre , Esquizofrenia/diagnóstico , Esquizofrenia/tratamiento farmacológico , Adulto Joven
10.
J Dairy Sci ; 102(11): 10360-10368, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31495620

RESUMEN

The problem of nonadherence to advice is recognized in several professional relationships, including the veterinarian-client relationship. A better understanding of farmer perspectives may help to improve efficiency in veterinary herd health management. This study aimed to qualitatively and quantitatively describe farmers' reasons for adherence and nonadherence with veterinary recommendations regarding preventive herd health measures. We carried out structured telephone interviews about implementation of preventive measures with owners or staff of 163 dairy farms and 6 beef farms. The farms had received an advisory visit by their veterinarian (n = 36), who had documented the preventive measures they had recommended. The interviewer noted verbatim responses to reasons for implementing preventive measures fully, partially, or not at all, and we analyzed these responses thematically. We also conducted a quantitative analysis, in which we calculated descriptive statistics of the proportions of different categories of reasons stated by the farmers. Altogether, 726 preventive measures (range per farm 1 to 17; median 3; interquartile range 2 to 6) were documented. We identified 3 organizing themes related to adherence or nonadherence with veterinary advice: trust, feasibility, and priorities. Overall, the most commonly stated reasons related to trust (in the veterinarian, in the advisory process, or in individual preventive measures). The most common reasons not to follow the recommended advice were related to feasibility. Based on the results, we recommend that, to improve adherence to their advice, veterinarians pay increased attention to farmers' needs, priorities, goals, and motives, as well as to farmers' perceptions of the effectiveness of individual preventive measures. We also recommend that veterinarians need to increase their focus on recommending preventive measures that are practically feasible to implement on farms.


Asunto(s)
Industria Lechera/métodos , Agricultores/psicología , Relaciones Públicas , Confianza , Veterinarios , Animales , Bovinos , Industria Lechera/normas , Granjas , Estudios de Factibilidad , Humanos , Entrevistas como Asunto , Motivación , Encuestas y Cuestionarios , Suecia
11.
J Dairy Sci ; 102(11): 10173-10185, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31521349

RESUMEN

Veterinary communication has evolved in the context of traditional veterinary tasks, such as diagnosing and treating sick animals, and this may encourage a directive communication style, in which the veterinarian acts as an expert, directing the client in what to do and how to do it. This type of communication style has been shown to evoke resistance to change in clients who are experiencing psychological ambivalence, a well-known aspect of farmers' herd health decisions. Veterinary herd health management (VHHM) constitutes an increasing proportion of the work of cattle veterinarians and often focuses on behavior change. The present study aimed to characterize communication styles of Swedish dairy cattle veterinarians involved in VHHM in relation to their skills in facilitating behavior change. A secondary aim was to investigate whether these skills differed among veterinarians depending on their experience in the veterinary profession or in VHHM. Audio-recorded role-play conversations (n = 123; reflecting VHHM telephone consultations) with 42 veterinarians involved in VHHM in Swedish dairy herds and audio-recorded on-farm consultations (n = 86) with 18 of those veterinarians were coded using a system developed to evaluate motivational interviewing (MI) skills. Motivational interviewing is a communication methodology aimed at facilitating clients' internal motivation to change. The MI Treatment Integrity (MITI) code identifies frequency counts of 10 verbal behaviors, and assesses 4 global variables on a Likert scale, based on 20 min of conversation. It also suggests 6 summary measurements of MI competency based on these 14 original variables. Of the 42 veterinarians, 39 also responded to a web questionnaire about their age, continuing education, and experience in the profession, in dairy herds and in VHHM. We analyzed associations between the 6 summary MITI variables from the role-play conversations and characteristics of the 39 veterinarians using logistic and linear multivariable regression models. Veterinarians in the role-play and on-farm conversations relied predominantly on giving information, questions, and persuasion in their consultation approaches. They generally did not explore the client's expectations or wishes regarding the agenda for the consultation, or acknowledge the client's right to make decisions about actions. Veterinarians gave advice without exploring the client's need for the advice or how the information was perceived. We found a significant reduction in so-called relational scores (Empathy plus Partnership) and an increase in MI-nonadherent behaviors (Persuasion plus Confront) as years of veterinary experience increased. Results showed that there is room for improvement in the communication style of veterinarians involved in VHHM. Wider literature suggests that training veterinarians in a client-centered communication methodology such as MI may increase the demand for and success of VHHM.


Asunto(s)
Enfermedades de los Bovinos/prevención & control , Comunicación , Agricultores/psicología , Entrevista Motivacional , Veterinarios , Animales , Conducta , Bovinos , Industria Lechera , Granjas , Femenino , Humanos , Modelos Lineales , Masculino , Registros , Derivación y Consulta , Encuestas y Cuestionarios , Suecia , Medicina Veterinaria
12.
Phys Rev Lett ; 118(15): 152502, 2017 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-28452556

RESUMEN

Angular distributions of the elastic, inelastic, and breakup cross sections of the halo nucleus ^{11}Be on ^{197}Au were measured at energies below (E_{lab}=31.9 MeV) and around (39.6 MeV) the Coulomb barrier. These three channels were unambiguously separated for the first time for reactions of ^{11}Be on a high-Z target at low energies. The experiment was performed at TRIUMF (Vancouver, Canada). The differential cross sections were compared with three different calculations: semiclassical, inert-core continuum-coupled-channels and continuum-coupled-channels ones with including core deformation. These results show conclusively that the elastic and inelastic differential cross sections can only be accounted for if core-excited admixtures are taken into account. The cross sections for these channels strongly depend on the B(E1) distribution in ^{11}Be, and the reaction mechanism is sensitive to the entanglement of core and halo degrees of freedom in ^{11}Be.

13.
Mol Psychiatry ; 21(10): 1342-50, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-26666201

RESUMEN

Elevated cerebrospinal fluid (CSF) levels of the glia-derived N-methyl-D-aspartic acid receptor antagonist kynurenic acid (KYNA) have consistently been implicated in schizophrenia and bipolar disorder. Here, we conducted a genome-wide association study based on CSF KYNA in bipolar disorder and found support for an association with a common variant within 1p21.3. After replication in an independent cohort, we linked this genetic variant-associated with reduced SNX7 expression-to positive psychotic symptoms and executive function deficits in bipolar disorder. A series of post-mortem brain tissue and in vitro experiments suggested SNX7 downregulation to result in a caspase-8-driven activation of interleukin-1ß and a subsequent induction of the brain kynurenine pathway. The current study demonstrates the potential of using biomarkers in genetic studies of psychiatric disorders, and may help to identify novel drug targets in bipolar disorder.


Asunto(s)
Trastorno Bipolar/genética , Ácido Quinurénico/metabolismo , Trastornos Psicóticos/genética , Adulto , Anciano , Trastorno Bipolar/líquido cefalorraquídeo , Trastorno Bipolar/metabolismo , Encéfalo/metabolismo , Cromosomas Humanos Par 1/genética , Trastornos del Conocimiento/complicaciones , Disfunción Cognitiva/genética , Disfunción Cognitiva/metabolismo , Femenino , Estudio de Asociación del Genoma Completo , Humanos , Ácido Quinurénico/líquido cefalorraquídeo , Masculino , Persona de Mediana Edad , Trastornos Psicóticos/complicaciones , Trastornos Psicóticos/metabolismo , Nexinas de Clasificación/genética
14.
Acta Psychiatr Scand ; 135(2): 159-169, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27922183

RESUMEN

OBJECTIVE: Therapeutic drug monitoring (TDM) of clozapine is standardized to 12-h postdose samplings. In clinical settings, sampling time often deviates from this time point, although the importance of the deviation is unknown. To this end, serum concentrations (s-) of clozapine and its metabolite N-desmethyl-clozapine (norclozapine) were measured at 12 ± 1 and 2 h postdose. METHOD: Forty-six patients with a diagnosis of schizophrenia, and on stable clozapine treatment, were enrolled for hourly, venous blood sampling at 10-14 h postdose. RESULTS: Minor changes in median percentage values were observed for both s-clozapine (-8.4%) and s-norclozapine (+1.2%) across the 4-h time span. Maximum individual differences were 42.8% for s-clozapine and 38.4% for s-norclozapine. Compared to 12-h values, maximum median differences were 8.4% for s-clozapine and 7.3% for s-norclozapine at deviations of ±2 h. Maximum individual differences were 52.6% for s-clozapine and 105.0% for s-norclozapine. The magnitude of s-clozapine differences was significantly associated with age, body mass index and the presence of chronic basophilia or monocytosis. CONCLUSION: The impact of deviations in clozapine TDM sampling time, within the time span of 10-14 h postdose, seems of minor importance when looking at median percentage differences. However, substantial individual differences were observed, which implies a need to adhere to a fixed sampling time.


Asunto(s)
Antipsicóticos/sangre , Clozapina/análogos & derivados , Clozapina/sangre , Esquizofrenia/tratamiento farmacológico , Adulto , Antipsicóticos/administración & dosificación , Clozapina/administración & dosificación , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Monitoreo de Drogas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esquizofrenia/sangre , Adulto Joven
15.
Scand J Immunol ; 84(5): 262-271, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27607184

RESUMEN

Tryptophan degradation along the kynurenine pathway is of central importance for the immune function. Toll-like receptors (TLRs), representing the first line of immune defence against pathogens, are expressed in various cell types. The most abundant expression is found on monocytes, macrophages and dendritic cells. The aim of this study was to investigate whether stimulation with different TLR ligands induces the kynurenine pathway in human peripheral monocytes. Cell supernatants were analysed using a liquid chromatography/mass spectrometry to measure kynurenine, kynurenic acid (KYNA), quinolinic acid (QUIN) and tryptophan. Stimulation of TLR-2, TLR-3, TLR-4, TLR-7/8 and TLR-9 was found to induce the production of kynurenine, but only stimulation of TLR-3 increased levels of further downstream metabolites, such as KYNA and QUIN. Stimulation of TLR-1, TLR-5 and TLR-6 did not induce the kynurenine pathway. Taken together, this study provides novel evidence demonstrating that TLR activation induces a pattern of downstream tryptophan degradation along the kynurenine pathway in monocytes. The results of this study may implicate that TLRs can be used as new drug targets for the regulation of aberrant tryptophan metabolism along this pathway, a potential therapeutic strategy that may be of importance in several disorders.


Asunto(s)
Quinurenina/inmunología , Monocitos/inmunología , Receptores Toll-Like/inmunología , Triptófano/inmunología , Flagelina/farmacología , Regulación de la Expresión Génica , Humanos , Hidrólisis , Imidazoles/farmacología , Ácido Quinurénico/inmunología , Ácido Quinurénico/metabolismo , Quinurenina/agonistas , Quinurenina/metabolismo , Lipopéptidos/farmacología , Lipopolisacáridos/farmacología , Listeria monocytogenes/química , Monocitos/citología , Monocitos/efectos de los fármacos , Poli I-C/farmacología , Cultivo Primario de Células , Isoformas de Proteínas/agonistas , Isoformas de Proteínas/genética , Isoformas de Proteínas/inmunología , Ácido Quinolínico/inmunología , Ácido Quinolínico/metabolismo , Transducción de Señal , Receptores Toll-Like/agonistas , Receptores Toll-Like/genética , Triptófano/metabolismo
16.
Phys Rev Lett ; 116(17): 172501, 2016 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-27176517

RESUMEN

Precision measurements of superallowed Fermi ß-decay transitions, particularly for the lightest superallowed emitters ^{10}C and ^{14}O, set stringent limits on possible scalar current contributions to the weak interaction. In the present work, a discrepancy between recent measurements of the ^{10}C half-life is addressed through two high-precision half-life measurements, via γ-ray photopeak and ß counting, that yield consistent results for the ^{10}C half-life of T_{1/2}=19.2969±0.0074 s and T_{1/2}=19.3009±0.0017 s, respectively. The latter is the most precise superallowed ß-decay half-life measurement reported to date and the first to achieve a relative precision below 10^{-4}. A fit to the world superallowed ß-decay data including the ^{10}C half-life measurements reported here yields b_{F}=-0.0018±0.0021 (68% C.L.) for the Fierz interference term and C_{S}/C_{V}=+0.0009±0.0011 for the ratio of the weak scalar to vector couplings assuming left-handed neutrinos.

17.
J Dairy Sci ; 96(10): 6315-23, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23958022

RESUMEN

The aim of this retrospective single-cohort study was to investigate if a rapid change in feeding, management, or housing or an increasing incidence of claw diseases or udder health problems is associated with decreased reproductive performance. Data on individual cows and herds were retrieved from the Swedish official milk recording system and questionnaire data on feeding system was obtained from the regional dairy associations. In total, 63,561 cows in 759 herds were included in the study. The associations between the probability of pregnancy at first insemination and number of inseminations per animal submitted for artificial insemination and potential predictor variables were investigated using a logistic regression model and a Poisson regression model, respectively. The results indicated that cows with severe claw lesions or an increasing somatic cell count after calving had a lower probability of pregnancy at first insemination and had a higher number of inseminations per animal submitted for artificial insemination than healthy cows. Variables representing a change in housing, production system, or milking system within the period from 6 mo before calving until establishment of a new pregnancy were significantly associated with decreased reproductive performance. No differences in fertility were observed between cows milked in an automatic milking system compared with cows milked conventionally. The results indicate that a change of system, rather than the actual type of milking or housing system negatively affects reproductive performance. Special attention should therefore be paid to the fertility of cows when the herd management is changing. It is also important to prevent claw lesions and increasing cell counts after calving to avoid a decrease in reproductive performance.


Asunto(s)
Enfermedades del Pie/veterinaria , Pezuñas y Garras/patología , Infertilidad Femenina/veterinaria , Inseminación Artificial/veterinaria , Animales , Bovinos , Recuento de Células/veterinaria , Industria Lechera , Femenino , Fertilidad , Infertilidad Femenina/epidemiología , Infertilidad Femenina/terapia , Inseminación Artificial/estadística & datos numéricos , Lactancia , Modelos Logísticos , Glándulas Mamarias Animales/fisiología , Leche/metabolismo , Embarazo , Reproducción , Estudios Retrospectivos
18.
Phys Rev Lett ; 109(4): 042301, 2012 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-23006079

RESUMEN

We report a precise determination of the (19)Ne half-life to be T(1/2)=17.262±0.007 s. This result disagrees with the most recent precision measurements and is important for placing bounds on predicted right-handed interactions that are absent in the current standard model. We are able to identify and disentangle two competing systematic effects that influence the accuracy of such measurements. Our findings prompt a reassessment of results from previous high-precision lifetime measurements that used similar equipment and methods.

19.
J Dairy Sci ; 95(12): 7086-96, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23021753

RESUMEN

Negative energy balance is a known risk factor for decreased fertility in dairy cows. This study evaluated the accuracy of plasma concentrations of nonesterified fatty acids (NEFA), ß-hydroxybutyrate (BHBA), and insulin-like growth factor 1 (IGF-1)-factors related to negative energy balance-in predicting decreased fertility. One plasma sample per cow was collected from 480 cows in 12 herds during the period from d 4 to 21 in milk and analyzed for NEFA, BHBA, and IGF-1. For each cow, data on breed, parity, calving date, gynecological examinations, and insemination dates were obtained. Milk samples from 241 cows in 7 of the participating herds were analyzed for progesterone concentration to define the first day of luteal activity. The diagnostic sensitivity (Se) and specificity (Sp) at different cut-off concentrations of NEFA, BHBA, or IGF-1 were calculated and related to individual cow fertility status, measured as anestrus (ANEST), delayed first artificial insemination (DFAI), or delayed conception. Positive and negative predictive values (PV+; PV-) were calculated considering different levels of (within-herd) prevalence. Strata (i.e., subgroup)-specific Se and Sp and associations between test results and fertility parameters were investigated using logistic regression. The NEFA and BHBA tests for ANEST and DFAI had the highest combined Se and Sp and were thus evaluated further. Cut-off values with Sp around 80% were used in this step to provide a reasonable number of test-positive cows, representing a practical situation. This corresponded to a cut-off value for the NEFA test of 400 µEq/L (Se 0.27-0.45) and for the BHBA test of 1.8mM (Se 0.15-0.30) across all cows included in the study. The estimated Sp was generally higher than the original 80%, but the corresponding Se was further decreased when the test was used in heifers compared with older cows. The true prevalence of ANEST in the study population was 27%, which gave a PV+ of 0.36 to 0.45 and a PV- of 0.76 to 0.79. With 35% true prevalence of DFAI, PV+ was 0.29 to 0.38 and PV- was 0.64 to 0.66. Thus, overall test performance was low when metabolic indicators measured as single values in early lactation were used to predict fertility in dairy cows, but accuracy was influenced by cow-level factors such as parity. The prevalence of the target condition (in this case, decreased fertility) also influences test usefulness and should be considered when planning test systems and interpreting test results.


Asunto(s)
Bovinos/fisiología , Fertilidad/fisiología , Ácido 3-Hidroxibutírico/sangre , Anestro/sangre , Anestro/metabolismo , Anestro/fisiología , Animales , Biomarcadores/sangre , Bovinos/sangre , Bovinos/metabolismo , Ácidos Grasos no Esterificados/sangre , Femenino , Factor I del Crecimiento Similar a la Insulina/análisis , Leche/química , Progesterona/análisis , Sensibilidad y Especificidad
20.
J Dairy Sci ; 95(5): 2397-408, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22541468

RESUMEN

The objective of this field study was to evaluate the effect of supplemental feeding with glycerol or propylene glycol to dairy cows in early lactation on metabolic status, body condition and milk yield. In total, 673 newly calved cows from 12 commercial Swedish dairy herds were randomized to daily supplementation with 450 g of glycerol (GLY), 300 g of propylene glycol (PG), or nothing (control, CON). Supplements were fed twice daily from 0 to 21 d in milk (DIM) as a top dress on concentrates. For each cow, data on parity, breed, calving date, monthly test-day milk yield, and cases of diseases were collected. Blood samples were taken at approximately 2, 5, and 8 wk postpartum (pp) and analyzed for glucose, ß-hydroxybutyrate (BHBA), nonesterified fatty acids (NEFA), and insulin. Samples taken within 3 wk pp were also analyzed for insulin-like growth factor 1 (IGF-1). Measurements of body condition score (BCS) and heart girth (HG) were obtained at approximately 2 and 5 wk pp and at time of first insemination. The effects of supplemental feeding with GLY or PG on the plasma concentrations of glucose, NEFA, BHBA, insulin, and IGF-1, and BCS, HG, and occurrence of disease were analyzed. No differences in BCS or HG or in plasma concentrations of glucose, BHBA, NEFA, or IGF-1 were found between the control group and any of the treatment groups. Cows in the GLY group had lower plasma insulin concentrations during DIM 0 to 63 compared with group CON, but no difference in insulin was found between the PG group and the CON group. Cows supplemented with GLY had a higher milk yield (kg of milk and kg of energy-corrected milk) during the first 90 DIM. Cows in the PG group tended to yield more milk during the same period. No differences in the occurrence of diseases were seen between the groups. In conclusion, supplementation with GLY in early lactation did increase milk yield without a subsequent decrease of metabolic status, and supplementation with PG tended to do the same.


Asunto(s)
Suplementos Dietéticos , Glicerol/farmacología , Lactancia/efectos de los fármacos , Propilenglicol/farmacología , Ácido 3-Hidroxibutírico/sangre , Animales , Glucemia/análisis , Bovinos/metabolismo , Ácidos Grasos no Esterificados/sangre , Femenino , Insulina/sangre , Factor I del Crecimiento Similar a la Insulina/análisis , Leche/metabolismo
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