Landscape Features Affecting Northern Bobwhite Predator-Specific Nest Failures in Southeastern USA

Nest predation is a critical component in avian productivity and typically is the leading cause of nest failure for most birds. Several landscape features are thought to drive the behavioral interaction between northern bobwhite (Colinus virginianus; e.g., nest placement) and their predators (e.g., search methods for food acquisition). In order to understand habitat characteristics influencing predation, we studied bobwhite nests using 24-hour near-infrared video cameras. We monitored 675 bobwhite nests with cameras on 3 properties in northern Florida and southern Georgia, USA, during 2000–2006. To test the association between nest failures and specific failure causes with landscape structure, we calculated a suite of landscape metrics and examined these at 3 spatial scales (3.1 ha, 19.6 ha, and 50.3 ha). We found increased probability of nest success with greater proportions of, and proximity to, fallow and annually disked fields at larger scales (50.3 ha), but we found no landscape metrics to be important predictors of bobwhite nest failures at small scales (,20 ha). Fallow and disked fields may provide alternative prey items (e.g., rodents) important in buffering nest predation. Relative to meso-mammal predation, we observed increases in proportion of the landscape in field to be related to lower incidental nest failures at the smallest scale (3.1 ha). Nests closer to feed lines were more likely depredated by meso-mammals than ants at the 2 larger spatial scales. Interestingly, the fate of a nest was independent of the fate of neighboring nests, suggesting bobwhite nest predation may be primarily incidental

Landscape Features Affecting Northern Bobwhite Predator-Specific Nest Failures in Southeastern USA

Nest predation is a critical component in avian productivity and typically is the leading cause of nest failure for most birds. Several landscape features are thought to drive the behavioral interaction between northern bobwhite (Colinus virginianus; e.g., nest placement) and their predators (e.g., search methods for food acquisition). In order to understand habitat characteristics influencing predation, we studied bobwhite nests using 24-hour near-infrared video cameras. We monitored 675 bobwhite nests with cameras on 3 properties in northern Florida and southern Georgia, USA, during 2000–2006. To test the association between nest failures and specific failure causes with landscape structure, we calculated a suite of landscape metrics and examined these at 3 spatial scales (3.1 ha, 19.6 ha, and 50.3 ha). We found increased probability of nest success with greater proportions of, and proximity to, fallow and annually disked fields at larger scales (50.3 ha), but we found no landscape metrics to be important predictors of bobwhite nest failures at small scales (\u3c20 \u3eha). Fallow and disked fields may provide alternative prey items (e.g., rodents) important in buffering nest predation. Relative to meso-mammal predation, we observed increases in proportion of the landscape in field to be related to lower incidental nest failures at the smallest scale (3.1 ha). Nests closer to feed lines were more likely depredated by meso-mammals than ants at the 2 larger spatial scales. Interestingly, the fate of a nest was independent of the fate of neighboring nests, suggesting bobwhite nest predation may be primarily incidental

The accuracy of chromosomal microarray testing for identification of embryonic mosaicism in human blastocysts

A dança é uma forma ancestral de magia, invenção dos deuses que a ensinaram aos homens, diz-nos a mitologia hindu. Envolvido no mistério e movimento da dança, o dançarino pode encantar; porém, antes de tudo é preciso que encante a si mesmo. Não seria este também o caminho do professor? Fazer para si para poder fazer ou propor aos educandos, encantar-se para poder encantar; criar para poder seguir com as crianças a aventura da criação; ousar para poder encorajar? Nesta direção, a pergunta que percorre o presente artigo é assim formulada: como contribuir com o processo de encantamento dos professores, como alimentar a sensibilidade, nos percursos da formação universitária? Buscando respostas no processo de pesquisa, identifica-se na experiência com as danças circulares, tradição de diferentes povos, um profícuo caminho pelo qual aquele espaço de encantamento, de inteireza, de educação estética, igualmente, pode ser provocado

Fast fluorescence microscopy for imaging the dynamics of embryonic development

Live imaging has gained a pivotal role in developmental biology since it increasingly allows real-time observation of cell behavior in intact organisms. Microscopes that can capture the dynamics of ever-faster biological events, fluorescent markers optimal for in vivo imaging, and, finally, adapted reconstruction and analysis programs to complete data flow all contribute to this success. Focusing on temporal resolution, we discuss how fast imaging can be achieved with minimal prejudice to spatial resolution, photon count, or to reliably and automatically analyze images. In particular, we show how integrated approaches to imaging that combine bright fluorescent probes, fast microscopes, and custom post-processing techniques can address the kinetics of biological systems at multiple scales. Finally, we discuss remaining challenges and opportunities for further advances in this field

S-Nitrosation of Protein Phosphatase 1 Mediates Alcohol-Induced Ciliary Dysfunction

Alcohol use disorder (AUD) is a strong risk factor for development and mortality of pneumonia. Mucociliary clearance, a key innate defense against pneumonia, is perturbed by alcohol use. Specifically, ciliated airway cells lose the ability to increase ciliary beat frequency (CBF) to β-agonist stimulation after prolonged alcohol exposure. We previously found that alcohol activates protein phosphatase 1 (PP1) through a redox mechanism to cause ciliary dysfunction. Therefore, we hypothesized that PP1 activity is enhanced by alcohol exposure through an S-nitrosothiol-dependent mechanism resulting in desensitization of CBF stimulation. Bronchoalveolar S-nitrosothiol (SNO) content and tracheal PP1 activity was increased in wild-type (WT) mice drinking alcohol for 6-weeks compared to control mice. In contrast, alcohol drinking did not increase SNO content or PP1 activity in nitric oxide synthase 3-deficient mice. S-nitrosoglutathione induced PP1-dependent CBF desensitization in mouse tracheal rings, cultured cells and isolated cilia. In vitro expression of mutant PP1 (cysteine 155 to alanine) in primary human airway epithelial cells prevented CBF desensitization after prolonged alcohol exposure compared to cells expressing WT PP1. Thus, redox modulation in the airways by alcohol is an important ciliary regulatory mechanism. Pharmacologic strategies to reduce S-nitrosation may enhance mucociliary clearance and reduce pneumonia prevalence, mortality and morbidity with AUD

Aggressive vs. conservative phototherapy for infants with extremely low birth weight.

BACKGROUND: It is unclear whether aggressive phototherapy to prevent neurotoxic effects of bilirubin benefits or harms infants with extremely low birth weight (1000 g or less). METHODS: We randomly assigned 1974 infants with extremely low birth weight at 12 to 36 hours of age to undergo either aggressive or conservative phototherapy. The primary outcome was a composite of death or neurodevelopmental impairment determined for 91% of the infants by investigators who were unaware of the treatment assignments. RESULTS: Aggressive phototherapy, as compared with conservative phototherapy, significantly reduced the mean peak serum bilirubin level (7.0 vs. 9.8 mg per deciliter [120 vs. 168 micromol per liter], P\u3c0.01) but not the rate of the primary outcome (52% vs. 55%; relative risk, 0.94; 95% confidence interval [CI], 0.87 to 1.02; P=0.15). Aggressive phototherapy did reduce rates of neurodevelopmental impairment (26%, vs. 30% for conservative phototherapy; relative risk, 0.86; 95% CI, 0.74 to 0.99). Rates of death in the aggressive-phototherapy and conservative-phototherapy groups were 24% and 23%, respectively (relative risk, 1.05; 95% CI, 0.90 to 1.22). In preplanned subgroup analyses, the rates of death were 13% with aggressive phototherapy and 14% with conservative phototherapy for infants with a birth weight of 751 to 1000 g and 39% and 34%, respectively (relative risk, 1.13; 95% CI, 0.96 to 1.34), for infants with a birth weight of 501 to 750 g. CONCLUSIONS: Aggressive phototherapy did not significantly reduce the rate of death or neurodevelopmental impairment. The rate of neurodevelopmental impairment alone was significantly reduced with aggressive phototherapy. This reduction may be offset by an increase in mortality among infants weighing 501 to 750 g at birth. (ClinicalTrials.gov number, NCT00114543.

Clinical performance and radiation dosimetry of no-carrier-added vs carrier-added 123I-metaiodobenzylguanidine (MIBG) for the assessment of cardiac sympathetic nerve activity

Purpose We hypothesized that assessment of myocardial sympathetic activity with no-carrier-added (nca) I-123-metaiodobenzylguanidine (MIBG) compared to carrier-added (ca) I-123-MIBG would lead to an improvement of clinical performance without major differences in radiation dosimetry. Methods In nine healthy volunteers, 15 min and 4 h planar thoracic scintigrams and conjugate whole-body scans were performed up to 48 h following intravenous injection of 185 MBq I-123-MIBG. The subjects were given both nca and ca I-123-MIBG. Early heart/mediastinal ratios (H/M), late H/M ratios and myocardial washout were calculated. The fraction of administered activity in ten source organs was quantified from the attenuation-corrected geometric mean counts in conjugate views. Radiation-absorbed doses were estimated with OLINDA/EXM software. Results Both early and late H/M were higher for nca I-123-MIBG (ca I-123-MIBG early H/M 2.46 +/- 0.15 vs nca I-123-MIBG 2.84 +/- 0.15, p = 0.001 and ca I-123-MIBG late H/M 2.69 +/- 0.14 vs nca I-123-MIBG 3.34 +/- 0.18, p = 0.002). Myocardial washout showed a longer retention time for nca I-123-MIBG (p <0.001). The effective dose equivalent (adult male model) for nca I-123-MIBG was similar to that for ca I-123-MIBG (0.025 +/- 0.002 mSv/MBq vs 0.026 +/- 0.002 mSv/MBq, p = 0.055, respectively). Conclusion No-carrier-added I-123-MIBG yields a higher relative myocardial uptake and is associated with a higher myocardial retention. This difference between nca I-123-MIBG and ca I-123-MIBG in myocardial uptake did not result in major differences in estimated absorbed doses. Therefore, nca I-123-MIBG is to be preferred over ca I-123-MIBG for the assessment of cardiac sympathetic activit

Development of the Adolescent Preoccupation with Screens Scale

Abstract Background Although public health concerns have been raised regarding the detrimental health effects of increasing rates of electronic screen use among adolescents, such effects have been small. Instruments currently available tend to be lengthy, have a clinical research focus, and assess young people’s screen use on specific screen-based activities (e.g., TV, computer, or internet). None appear to address screen use across a broad range of screens, including mobile devices and screen-based activities. The objective was to develop a new and short self-report scale for investigating adolescents’ screen use across all screens and screen-based activities in non-clinical settings. Methods The Adolescent Preoccupation with Screens Scale (APSS) was developed over a three stage process. First, a review of the current literature and existing instruments was undertaken and suitable items identified. Second, the draft APSS was piloted with adolescents and item affectivity and discrimination indices were calculated. Third, a cross sectional school based online survey of 1967 Australian adolescents in grades 5 (10 years old), 7 (13 years) and 9 (15 years) from 25 randomly selected schools was conducted. Results Factor Analysis on a sub-sample of the data (n = 782) and Confirmatory Factor Analysis on the remaining sub-sample (n = 1185), supported a two-factor model. The first factor reflects adolescents’ mood management with screen use, and the second reflects a behavioural preoccupation. The measure demonstrated strong invariance across sex and across Grades 5, 7, and 9. Both factors displayed good internal consistency (α = .91 and .87, respectively). Sex and grade differences on both scales were investigated and boys in Grade 5 reported higher levels of both mood management and behavioural preoccupation with screens. There were no sex differences on mood management in Grades 7 and 9, but girls reported higher behavioural preoccupation in both these later grades. Conclusion The APSS provides researchers with a new, brief and robust measure of potentially problematic screen use across a wide array of screens, including mobile devices, so readily accessed during adolescence

Nanostructures, Technology, Research, and Applications

Contains reports on twenty research projects and a list of publications.Joint Services Electronics Program Grant DAAH04-95-1-0038National Science Foundation Grant ECS-94-07078Semiconductor Research CorporationU.S. Army Research Office Grant DAAH04-95-1-0564Defense Advanced Research Projects Agency/Naval Air Systems Command Contract N00019-95-K-0131National Aeronautics and Space Administration Contract NAS8-38249National Aeronautics and Space Administration Grant NAGW-2003IBM Corporation Contract 1622National Science Foundation Graduate FellowshipU.S. Navy - Office of Naval Research Grant N00014-95-1-1297U.S. Army Research Office Contract DAAH04-94-G-0377U.S. Air Force - Office of Scientific Research Grant F49620-92-J-0064U.S. Air Force - Office of Scientific Research Grant F49620-95-1-0311National Science Foundation Contract DMR 94-0034U.S. Air Force - Office of Scientific Research Contract F49620-96-0126Harvard-Smithsonian Astrophysical Observatory Contract SV630304National Aeronautics and Space Administration Grant NAG5-5105Los Alamos National Laboratory Contract E57800017-9

A novel piggybac transposon inducible expression system identifies a role for akt signalling in primordial germ cell migration

In this work, we describe a single piggyBac transposon system containing both a tet-activator and a doxycycline-inducible expression cassette. We demonstrate that a gene product can be conditionally expressed from the integrated transposon and a second gene can be simultaneously targeted by a short hairpin RNA contained within the transposon, both in vivo and in mammalian and avian cell lines. We applied this system to stably modify chicken primordial germ cell (PGC) lines in vitro and induce a reporter gene at specific developmental stages after injection of the transposon-modified germ cells into chicken embryos. We used this vector to express a constitutively-active AKT molecule during PGC migration to the forming gonad. We found that PGC migration was retarded and cells could not colonise the forming gonad. Correct levels of AKT activation are thus essential for germ cell migration during early embryonic development