To what extent does photoperiod affect cattle reproduction? Clinical perspectives of melatonin administration

The seasonality of reproduction in most mammals is dictated by photoperiod, temperature and nutrition. Melatonin, mainly synthesized in the pineal gland, is generally accepted as the active mediator of photoperiod responses including reproduction. While non-pregnant heifers and cows show continuous sexual activity and are therefore not seasonal breeders, it has been suggested that photo-periodicity may influence the appearance of puberty in heifers and the onset of parturition. Further, the light/dark ratio may influence endocrine patterns of gestation and a shorter light period correlates with the incidence of twin pregnancies. This review considers specific aspects of the effects of photoperiod and melatonin on reproduction in dairy cattle and discusses the clinical applications of melatonin

Effect of utilization of single or double prostaglandin administration within an ovsynch fixed-time artificial insemination protocol during summer season in dairy cows

This study investigated the fertility of dairy cows during summer season after treatment with a single or double PGF2α in a progesterone (P4)-based Ovsynch protocol for fixed-time artificial insemination (FTAI). The data were compared to a treatment effectuated during winter season. Two groups of 60 dairy cows each were randomly assigned on day 60 post-partum to single PGF2α or double PGF2α group. At removal of the P4 treatment the single PGF2α group received a single dose and the double PGF2α group received two doses of PGF2α at 24 hours apart. In each group, 30 cows were treated during the summer (June, July and August) and 30 cows during the winter (December, January and February) season. During summer season a double PGF2α dose did not influence pregnancy rate at FTAI but improved cumulative pregnancy rate 60 days after FTAI (43% vs 69% for single PGF2α and double PGF2α administration, respectively; P<0.05). During winter season the single or double PGF2α administration did not modify PR or cumulative PR. In conclusion, during summer the utilization of a double instead of single PGF2α treatment into a P4-based Ovsynch-FTAI protocol did not increase pregnancy rate at FTAI but improved cumulative pregnancy rate

A second order minimality condition for the Mumford-Shah functional

A new necessary minimality condition for the Mumford-Shah functional is derived by means of second order variations. It is expressed in terms of a sign condition for a nonlocal quadratic form on $H^1_0(\Gamma)$, $\Gamma$ being a submanifold of the regular part of the discontinuity set of the critical point. Two equivalent formulations are provided: one in terms of the first eigenvalue of a suitable compact operator, the other involving a sort of nonlocal capacity of $\Gamma$. A sufficient condition for minimality is also deduced. Finally, an explicit example is discussed, where a complete characterization of the domains where the second variation is nonnegative can be given.Comment: 30 page

Comparação da fauna de formigas de serapilheira entre área de floresta atlântica secundária e plantação adjacente de pinus no sudeste do Brasil

We investigated the influence of Pinus afforestation on the structure of leaf-litter ant communities in the southeastern Brazilian Atlantic Forest, studying an old secondary forest and a nearly 30 year-old never managed Pinus elliottii reforested area. A total of 12,826 individual ants distributed among 95 species and 32 genera were obtained from 50 1 m² samples/ habitat. Of these, 60 species were recorded in the pine plantation and 82 in the area of Atlantic forest; almost 50% of the species found in the secondary forest area were also present in the pine plantation. The number of species per sample was significantly higher in the secondary forest than in the pine plantation. Forest-adapted taxa are the most responsible for ant species richness differences between areas, and the pine plantation is richer in species classified as soil or litter omnivorous-dominants. The specialized ant predators registered in the pine plantation, as seven Dacetini, two Basiceros, two Attini and two Discothyrea, belong to widely distributed species. The NMDS (non-metric multidimensional scaling) ordination also suggested strong differences in similarity among samples of the two areas. Furthermore, this analysis indicated higher sample heterogeneity in the secondary forest, with two clusters of species, while in the pine plantation the species belong to a single cluster. We applied the ant mosaic hypothesis to explain the distribution of the leaf-litter fauna and spatial autocorrelation tests among samples. We argue that the results are likely related to differences in quality and distribution of the leaf-litter between the pine plantation and the secondary area.A influência do reflorestamento com Pinus na estrutura da fauna de formigas de serapilheira foi investigada, estudando uma floresta Atlântica secundária inalterada há 30 anos e uma área reflorestada com Pinus elliottii no Sudeste do Brasil. Em 50 amostras de 1 m² tomadas em cada área, foram coletados 12.826 indivíduos, distribuídos em 95 espécies e 32 gêneros de formigas. Foram identificadas 60 espécies na área reflorestada com Pinus e 82 espécies na área de floresta secundária; aproximadamente 50% das espécies foram registradas nas duas áreas. A mediana do número de espécies por amostra foi maior na floresta secundária. Táxons com biologia especializada são responsáveis por grande parte das diferenças de composição de fauna, sendo a área de reflorestamento com Pinus mais rica em espécies onívoras e dominantes. Predadoras especializadas registradas na área de Pinus, como sete espécies de Dacetini, duas Basiceros, duas Attini e duas Discothyrea, têm ampla distribuição na Floresta Atlântica. A ordenação das amostras com o escalonamento multidimensional não-métrico (NMDS) indicou grande diferença na similaridade entre as amostras das áreas. Adicionalmente, essa análise sugere maior heterogeneidade na composição das amostras da floresta secundária, identificando dois agrupamentos de espécies, enquanto a área de Pinus apresenta um agrupamento apenas. Para investigar quais fatores podem explicar a heterogeneidade observada, testes de co-ocorrência e de autocorrelação espacial foram aplicados entre amostras de cada área. Nossa conclusão é que as diferenças observadas devem estar relacionadas com diferenças na qualidade e distribuição da serapilheira entre as áreas.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)UMC - Fundação de Amparo ao Ensino e Pesquis

Novel sequence variants of viral hexon and fibre genes in two dogs with canine adenovirus type 1-associated disease

There is little information on sequence variation of canine adenovirus type 1 (CAdV-1), the aetiological agent of infectious canine hepatitis (ICH). This study reports hexon and fibre gene sequence variants of CAdV-1 in a dog with systemic ICH and a dog with the ocular form of the disease (\ue2\u80\u98blue eye\ue2\u80\u99) in Northern Italy in 2013. One of the sequence variants matched a CAdV-1 fox sequence previously detected in Italy

Absence of acquired copy number neutral loss of heterozygosity (CN-LOH) of chromosome 7 in a series of 10 patients with Shwachman-Diamond syndrome

We report that acquired copy number neutral loss of heterozygosity (CN-LOH) of chromosome 7 was not identified in a series of 10 patients with Shwachman\u2013Diamond syndrome (SDS)

Studio longitudinale sul benessere e le attitudini degli Studenti di Medicina e Chirurgia. Primi risultati della fase 1: Le caratteristiche degli studenti selezionati

We present the first results of a longitudinal study for the recognition and assessment of non-cognitive aspects of the candidates access to medicine course, and throughout the course. This study considered 8 CLMs equally distributed throughout the country and 980 students enrolled in the first year, in the academic year 2013-2014. Preliminary results obtained from the analysis of the questionnaire used in the research show that students expect a profession characterized by the aid for patients and socially useful, while they do not expect a low pay as well as a work activity risky for health. Students are motivated to the academic course mainly by the desire to care for others, while variously opportunistic aspects are much less relevant. Students show high capacity of self-regulation, a high level of empathy in its both aspects of propensity to engagement with others in their difficult moments, as well as of tendency to spontaneously take the perspective of others, while they are able to maintain a goal directed behavior even in the presence of suffering others. These students are basically satisfied, they show a confident and positive attitude towards life and a substantial psychological health. However, it is possible to identify a sub-group of students showing signals of psychological fragility who must be carefully monitored: their profiles will be analyzed in more detail, through in-depth interviews scheduled for the third/fourth year as part of faculties counselling services

Chandra Phase-Resolved X-ray Spectroscopy of the Crab Pulsar II

We present a new study of the X-ray spectral properties of the Crab Pulsar. The superb angular resolution of the Chandra X-ray Observatory enables distinguishing the pulsar from the surrounding nebulosity. Analysis of the spectrum as a function of pulse phase allows the least-biased measure of interstellar X-ray extinction due primarily to photoelectric absorption and secondarily to scattering by dust grains in the direction of the Crab Nebula. We modify previous findings that the line-of-sight to the Crab is under-abundant in oxygen and provide measurements with improved accuracy and less bias. Using the abundances and cross sections from Wilms, Allen & McCray (2000) we find [O/H] = $(5.28 \pm 0.28)\times10^{-4}$ ($4.9 \times10^{-4}$ is solar abundance). We also measure for the first time the impact of scattering of flux out of the image by interstellar grains. We find $\tau_{\rm scat} = 0.147 \pm 0.043$. Analysis of the spectrum as a function of pulse phase also measures the X-ray spectral index even at pulse minimum --- albeit with increasing statistical uncertainty. The spectral variations are, by and large, consistent with a sinusoidal variation. The only significant variation from the sinusoid occurs over the same phase range as some rather abrupt behavior in the optical polarization magnitude and position angle. We compare these spectral variations to those observed in Gamma-rays and conclude that our measurements are both a challenge and a guide to future modeling and will thus eventually help us understand pair cascade processes in pulsar magnetospheres. The data were also used to set new, and less biased, upper limits to the surface temperature of the neutron star for different models of the neutron star atmosphere.Comment: 32 pages, 6 figures submitted to the Astrophysical journa

An XMM-Newton view of the `bare' nucleus of Fairall 9

We present the spectral results from a 130 ks observation, obtained from the X-ray Multi-Mirror Mission-Newton (XMM-Newton) observatory, of the type I Seyfert galaxy Fairall 9. An X-ray hardness-ratio analysis of the light-curves, reveals a `softer-when-brighter' behaviour which is typical for radio-quiet type I Seyfert galaxies. Moreover, we analyse the high spectral-resolution data of the reflection grating spectrometer and we did not find any significant evidence supporting the presence of warm-absorber in the low X-ray energy part of the source's spectrum. This means that the central nucleus of Fairall 9 is `clean' and thus its X-ray spectral properties probe directly the physical conditions of the central engine. The overall X-ray spectrum in the 0.5-10 keV energy-range, derived from the EPIC data, can be modelled by a relativistically blurred disc-reflection model. This spectral model yields for Fairall 9 an intermediate black-hole best-fit spin parameter of $\alpha=0.39^{+0.48}_{-0.30}$.Comment: Accepted for publication in MNRAS. The paper contains 11 figures and 1 tabl