32 research outputs found
Within-season changes in habitat use of forest-dwelling boreal bats
Bats utilize forests as roosting sites and feeding areas. However, it has not been documented how bats utilize these habitats in the boreal zone with methods afforded by recent technological advances. Forest structure and management practices can create a variety of three-dimensional habitats for organisms capable of flight, such as bats. Here, we study the presence of boreal bats in a forest forming a mosaic of different age classes, dominant tree species, canopy cover, soil fertility, and other environmental variables, throughout their active season in the summer using passive ultrasound detectors. Our results indicate a preference for mature forest by Eptesicus nilssonii and a pooled set of Myotis bats. Both groups of bats also showed temporal changes in their habitat use regarding forest age. In June and July, both groups occurred more often in mature than young forests, but from August onwards, the difference in occurrence became less evident in Myotis and disappeared completely in E. nilssonii. In addition, E. nilssonii was more often present in forests with low canopy cover, and its occurrence shifted from coniferous forests to deciduous forests during the season. The results reflect the within-season dynamics of bat communities and their ability to utilize different types of forest as environmental conditions change. Yet, the results most importantly emphasize the importance of mature forests to bat diversity and the need to conserve such environments in the boreal zone.Peer reviewe
The Fueling and Evolution of AGN: Internal and External Triggers
In this chapter, I review the fueling and evolution of active galactic nuclei
(AGN) under the influence of internal and external triggers, namely intrinsic
properties of host galaxies (morphological or Hubble type, color, presence of
bars and other non-axisymmetric features, etc) and external factors such as
environment and interactions. The most daunting challenge in fueling AGN is
arguably the angular momentum problem as even matter located at a radius of a
few hundred pc must lose more than 99.99 % of its specific angular momentum
before it is fit for consumption by a BH. I review mass accretion rates,
angular momentum requirements, the effectiveness of different fueling
mechanisms, and the growth and mass density of black BHs at different epochs. I
discuss connections between the nuclear and larger-scale properties of AGN,
both locally and at intermediate redshifts, outlining some recent results from
the GEMS and GOODS HST surveys.Comment: Invited Review Chapter to appear in LNP Volume on "AGN Physics on All
Scales", Chapter 6, in press. 40 pages, 12 figures. Typo in Eq 5 correcte
Heavy quarkonium: progress, puzzles, and opportunities
A golden age for heavy quarkonium physics dawned a decade ago, initiated by
the confluence of exciting advances in quantum chromodynamics (QCD) and an
explosion of related experimental activity. The early years of this period were
chronicled in the Quarkonium Working Group (QWG) CERN Yellow Report (YR) in
2004, which presented a comprehensive review of the status of the field at that
time and provided specific recommendations for further progress. However, the
broad spectrum of subsequent breakthroughs, surprises, and continuing puzzles
could only be partially anticipated. Since the release of the YR, the BESII
program concluded only to give birth to BESIII; the -factories and CLEO-c
flourished; quarkonium production and polarization measurements at HERA and the
Tevatron matured; and heavy-ion collisions at RHIC have opened a window on the
deconfinement regime. All these experiments leave legacies of quality,
precision, and unsolved mysteries for quarkonium physics, and therefore beg for
continuing investigations. The plethora of newly-found quarkonium-like states
unleashed a flood of theoretical investigations into new forms of matter such
as quark-gluon hybrids, mesonic molecules, and tetraquarks. Measurements of the
spectroscopy, decays, production, and in-medium behavior of c\bar{c}, b\bar{b},
and b\bar{c} bound states have been shown to validate some theoretical
approaches to QCD and highlight lack of quantitative success for others. The
intriguing details of quarkonium suppression in heavy-ion collisions that have
emerged from RHIC have elevated the importance of separating hot- and
cold-nuclear-matter effects in quark-gluon plasma studies. This review
systematically addresses all these matters and concludes by prioritizing
directions for ongoing and future efforts.Comment: 182 pages, 112 figures. Editors: N. Brambilla, S. Eidelman, B. K.
Heltsley, R. Vogt. Section Coordinators: G. T. Bodwin, E. Eichten, A. D.
Frawley, A. B. Meyer, R. E. Mitchell, V. Papadimitriou, P. Petreczky, A. A.
Petrov, P. Robbe, A. Vair
Geographical and temporal distribution of SARS-CoV-2 clades in the WHO European Region, January to June 2020
We show the distribution of SARS-CoV-2 genetic clades over time and between countries and outline potential genomic surveillance objectives. We applied three available genomic nomenclature systems for SARS-CoV-2 to all sequence data from the WHO European Region available during the COVID-19 pandemic until 10 July 2020. We highlight the importance of real-time sequencing and data dissemination in a pandemic situation. We provide a comparison of the nomenclatures and lay a foundation for future European genomic surveillance of SARS-CoV-2.Peer reviewe
Probiotics and antibiotics as additives for sows and piglets during nursery phase Probióticos e antibióticos como aditivos para matrizes e leitões na fase de creche
The purpose of this study was to evaluate the effects of the use of probiotics in diets for sows and piglets on performance and morphophysiologic parameters and the incidence of diarrhea in piglets during 28 days after weaning. A total of 120 pigs weaned at 21 days of age from 24 litters whose sows (primiparous) received probiotics or antibiotics from the 94th day of gestation until weaning. It was used a complete randomized design in a 2 × 3 factorial (probiotics or antibiotics for sows and three diets for piglets - antibiotics, probiotics or probiotic-antibiotic combination) with four replicates of five animals to evaluate the performance and incidence of diarrhea. At 28 days of experiment, two animals from each plot were sacrificed for histological parameter measurement of the pH of the stomach, jejunum and cecum. The association antibiotics+ probiotics in the diet of pigs resulted in greater weight gain and feed intake in animals born from of sows which received probiotics during the gestation and lactation phases. When females received antibiotics, the piglets receiving only probiotics showed higher consumption, but there were no differences for feed conversion. The use of antibiotics + probiotics in diets for piglets reduced the pH of the cecum and, when associated with the use of probiotics for sows, villous:crypt ratio in the jejunum increased. The use of growth promoters did not affect stomach pH neither the incidence of diarrhea. Supply of probiotics in the diet of sows during the gestation and lactation phases associated to the use in the diet of piglets after weaning is effective in maintaining animal performance, to histophysiological conditions in the gastrointestinal tract and control of diarrhea during the nursery phase.<br>O objetivo neste trabalho foi avaliar os efeitos do uso de probióticos em dietas para matrizes e leitões, sobre o desempenho, os parâmetros morfofisiológicos e a indicência de diarréia nos leitões durante 28 dias após o desmame. Foram utilizados 120 leitões desmamados aos 21 dias, provenientes de 24 leitegadas cujas matrizes (primíparas) receberam probióticos ou antibióticos a partir do 94º dia de gestação até o desmame. Foi utilizado um delineamento inteiramente casualizado em esquema fatorial 2 × 3 (probióticos ou antibióticos para matrizes e três dietas para leitões - antibióticos, probióticos ou associação antibiótico-probiótico) com quatro repetições de cinco animais para avaliação do desempenho e da incidência de diarreia. Aos 28 dias de experimento, dois animais de cada parcela foram sacrificados para mensuração de parâmetros histológicos do jejuno e pH do estômago e ceco. A associação probióticos + antibióticos na dieta dos leitões resultou em maior ganho de peso e consumo de ração nos animais filhos das matrizes que receberam probióticos durante as fases de gestação e lactação. Quando as fêmeas receberam antibióticos, os leitões que receberam apenas probióticos apresentaram maior consumo, porém não foram observadas diferenças na conversão alimentar. O uso de antibióticos + probióticos na dieta de leitões reduziu o pH do ceco e, quando associado ao uso de probióticos para matrizes, aumentou a relação vilosidade:cripta do jejuno. O uso de promotores de crescimento não influenciou o pH estomacal nem a incidência de diarreia. O fornecimento de probióticos na dieta das matrizes durante as fases de gestação e lactação em assossiação ao uso na dieta dos leitões após o desmame é eficaz em manter o desempenho dos animais, às condições histofisiológicas do trato gastrintestinal e o controle de diarreia durante a fase de creche
microRNA expression profiles and personal monitoring of exposure to particulate matter
An increasing number of findings from epidemiological studies support associations between exposure to air pollution and the onset of several diseases, including pulmonary, cardiovascular and neurodegenerative diseases, and malignancies. However, intermediate, and potentially mediating, biological mechanisms associated with exposure to air pollutants are largely unknown. Previous studies on the human exposome have shown that the expression of certain circulating microRNAs (miRNAs), regulators of gene expression, are altered upon exposure to traffic-related air pollutants. In the present study, we investigated the relationship between particulate matter (PM) smaller than 2.5 μm (PM2.5), PM2.5 absorbance (as a proxy of black carbon and soot), and ultrafine-particles (UFP, smaller than 0.1 μm), measured in healthy volunteers by 24 h personal monitoring (PEM) sessions and global expression levels of peripheral blood miRNAs. The PEM sessions were conducted in four European countries, namely Switzerland (Basel), United Kingdom (Norwich), Italy (Turin), and The Netherlands (Utrecht). miRNAs expression levels were analysed using microarray technology on blood samples from 143 participants. Seven miRNAs, hsa-miR-24-3p, hsa-miR-4454, hsa-miR-4763-3p, hsa-miR-425-5p, hsa-let-7d-5p, hsa-miR-502-5p, and hsa-miR-505-3p were significantly (FDR corrected) expressed in association with PM2.5 personal exposure, while no significant association was found between miRNA expression and the other pollutants. The results obtained from this investigation suggest that personal exposure to PM2.5 is associated with miRNA expression levels, showing the potential for these circulating miRNAs as novel biomarkers for air pollution health risk assessment