Evaluation of corn and barley varieties in extensive winter grazing systems for beef calves

Two experiments were conducted to determine the suitability of whole plant corn as an alternative forage to whole plant barley for winter grazing and the subsequent effect of extensive winter grazing systems on performance and carcass characteristics of beef steers during feedlot finishing. Experiment 1 evaluated the in vitro digestibility of dry matter (IVDMD) and neutral detergent fibre (IVNDFD) of whole plant corn (COR), whole plant barley (BAR) and processed barley hay (CON) collected on October and February sampling dates over 2 yrs. COR forage had similar (P>0.05) IVDMD and IVNDF to both CON or BAR forage. The IVDMD and IVNDFD also remained similar (P>0.05) between the October and February sampling date for COR and BAR forages and processed barley hay. Experiment 2 evaluated the effects of grazing either swathed whole plant barley, standing whole plant corn, or drylot fed barley hay on forage quality, estimated intake, calf performance and backgrounding production costs over 2 years. In each year, 120 spring born Angus calves (263.3 ± 5 kg; 169 d of age) were fall weaned, stratified by body weight and randomly allocated to 1 of 3 replicated (n = 2) backgrounding systems: 1) field grazing standing whole plant corn (COR); 2) field grazing swathed whole plant barley (BAR); or 3) dry lot (CON) bunk fed processed barley hay. Calves fed COR and BAR were limit grazed in 4-ha paddocks for a 3-d grazing period using electric fencing for an average of 97 d over 2 yr, with all calves receiving a pelleted supplement (78% TDN, 16% CP) daily at 0.8% BW. A randomized complete block design (RCBD) was used to analyze crop yield, crop quality, dry matter intake (DMI), body weight (BW), average daily gain (ADG), total system cost and cost of gain (COG) over the 2 yr trial. Forage samples were collected every 21 d to determine forage quality. Protein content was greater (P0.05) from either CON or BAR forage. Acid detergent fibre was not different (P>0.05) between the 3 forage types. Total digestible nutrients and net energy for gain were greater (P0.05) in DMI, BW, ADG or COG between the 3 backgrounding systems. Total cost of production was greatest (P0.05) in BW, DMI, ADG, yield grade or carcass characteristics among systems, suggesting that backgrounding calves by field grazing either standing whole plant corn or swathed barley is a viable option to decrease winter feeding costs without having an effect on finishing performance

The Genetic Analysis of Autophagy-Dependent Caspase Activation in Drosophila melanogaster

During Drosophila melanogaster pupation, groups of undifferentiated adult cells proliferate and undergo regulated cell shape changes, while larval tissues are eliminated by programmed cell death (PCD). PCD is most commonly associated with apoptosis; however, a growing body of evidence suggests that autophagic cell death represents an alternative form of PCD. In some contexts autophagy can induce caspase-dependent PCD, but the regulatory pathways that link autophagy and apoptosis remain poorly understood. The overexpression of Atg16B induces autophagy-dependent caspase activation in the larval epidermis, and presumptive adult tissues. Also, the overexpression of Atg16B, in tissues specified by pnrGAL4, results in an adult cuticular phenotype that cannot be directly attributed to caspase activity. However, altering the level of Atg16B expression can modulate the adult cuticular phenotype. Therefore, the adult cuticular phenotype was used in a broad based genome-wide screen for dose-dependent modifiers of the regulation of autophagy. To date, 399 chromosomal deficiencies, representing approximately 92% of the 2nd and 3rd chromosomes, and 25 duplications have been tested. Consequently, 42 deficiencies have been identified as dominant enhancers of the Atg16B overexpression phenotype, 24 deficiencies have been identified as dominant modifiers, and 13 deficiencies have been identified as dominant suppressors. Further genetic analysis of these interacting deficiencies was carried out to initiate the process of identifying individual loci associated with the dose-sensitive modification of the Atg16B overexpression phenotype. It is hoped that the identification of these genes will elucidate the genetic pathways regulating autophagy and the autophagic induction of caspase activity.1 yea

The Preparation of Drosophila Embryos for Live-Imaging Using the Hanging Drop Protocol

Green fluorescent protein (GFP)-based timelapse live-imaging is a powerful technique for studying the genetic regulation of dynamic processes such as tissue morphogenesis, cell-cell adhesion, or cell death. Drosophila embryos expressing GFP are readily imaged using either stereoscopic or confocal microscopy. A goal of any live-imaging protocol is to minimize detrimental effects such as dehydration and hypoxia. Previous protocols for preparing Drosophila embryos for live-imaging analysis have involved placing dechorionated embryos in halocarbon oil and sandwiching them between a halocarbon gas-permeable membrane and a coverslip1-3. The introduction of compression through mounting embryos in this manner represents an undesirable complication for any biomechanical-based analysis of morphogenesis. Our method, which we call the hanging drop protocol, results in excellent viability of embryos during live imaging and does not require that embryos be compressed. Briefly, the hanging drop protocol involves the placement of embryos in a drop of halocarbon oil that is suspended from a coverslip, which is, in turn, fixed in position over a humid chamber. In addition to providing gas exchange and preventing dehydration, this arrangement takes advantage of the buoyancy of embryos in halocarbon oil to prevent them from drifting out of position during timelapse acquisition. This video describes in detail how to collect and prepare Drosophila embryos for live imaging using the hanging drop protocol. This protocol is suitable for imaging dechorionated embryos using stereomicroscopy or any upright compound fluorescence microscope

Deliberation, Cognitive Complexity, and Political Engagement: A Longitudinal Study of the Impact of Deliberative Training During Emerging Adulthood

Young adults who had participated in a college program in which they learned to deliberate were compared with a matched sample from the same college who did not participate. Interview and survey responses to questions about citizenship and communication about politics were analyzed. Ten years after their graduation, the students who learned to deliberate during college had more complex conceptions of citizenship and its responsibilities compared to their 2005 classmates in the matched cohort. They also expressed more willingness to engage in political talk across differences. The study suggests that when emerging adults have extended experience deliberating about potentially divisive policy issues, they develop cognitive and communicative skills that equip them to navigate the diverse socio-political world that they now inhabit. Thus, we argue that education for democracy in the 21st century should include instruction in deliberative practice

Efficacy of dasatinib for the treatment of intractable chronic myeloid leukemia

Dasatinib (DAS) is a well tolerated oral dual SRC inhibitor with remarkable activity against all phases of imatinib-resistant chronic myeloid leukemia (CML). This paper focuses on the activity of DAS in intractable CML, and reviews outcomes of patients enrolled on DAS clinical trials. Safety and tolerability as well as practical tips for management of side-effects, and drug interactions are included

External review of the IDRC Climate Change and Water Program : final report

The program focuses on climate change, water availability, adaptive capacity, and identification and implementation of practical adaptation measures. With few standard methodologies, limited developing country research capacity, demanding interdisciplinary approaches, and poorly defined policy targets, the program was developed and implemented in a challenging context. In the face of a rapidly changing field, strategy evolution showed few significant shifts, and these were documented and justified in context; reasonable implementation choices were made that capitalized on opportunities. The panel found the quality of different projects is diverse and widely distributed, with good performance in elements of research integrity, originality and relevance

A Lay Health Worker Intervention to Increase Uptake and Completion of Pulmonary Rehabilitation in Chronic Obstructive Pulmonary Disease: Assessing Fidelity of Intervention Delivery

“This is an Accepted Manuscript of an article published by Taylor & Francis Group in COPD: Journal of Chronic Obstructive Pulmonary Disease on 17 Aug 2020, available online: https://doi.org/10.1080/15412555.2020.1797658

A simple method for construction of pir+ Enterobacterial hosts for maintenance of R6K replicon plasmids

<p>Abstract</p> <p>Background</p> <p>The R6K replicon is one of the best studied bacterial plasmid replicons. Replication of the R6K plasmid and derivatives harboring its γ origin of replication (<it>ori</it>_R6Kγ) is dependent on the <it>pir </it>gene-encoded π protein. Originally encoded by R6K, this protein is usually provided <it>in trans </it>in hosts engineered to support replication of plasmids harboring <it>ori</it>_R6Kγ. In <it>Escherichia coli </it>this is commonly achieved by chromosomal integration of <it>pir </it>either via lysogenization with a λ<it>pir </it>phage or homologous recombination at a pre-determined locus.</p> <p>Findings</p> <p>Current methods for construction of host strains for <it>ori</it>_R6Kγ-containing plasmids involve procedures that do not allow selection for presence of the <it>pir </it>gene and require cumbersome and time-consuming screening steps. In this study, we established a mini-Tn<it>7</it>-based method for rapid and reliable construction of <it>pir</it>⁺host strains. Using a curable mini-Tn<it>7 </it>delivery plasmid, <it>pir </it>expressing derivatives of several commonly used <it>E. coli </it>cloning and mobilizer strains were isolated using both the wild-type <it>pir⁺</it>gene as well as the copy-up <it>pir-116 </it>allele. In addition, we isolated <it>pir</it>⁺and <it>pir-116 </it>expressing derivatives of a clinical isolate of <it>Salmonella enterica </it>serovar Typhimurium. In both <it>E. coli </it>and <it>S. enterica </it>serovar Typhimurium, the presence of the <it>pir⁺</it>wild-type or <it>pir-116 </it>alleles allowed the replication of <it>ori</it>_R6Kγ-containing plasmids.</p> <p>Conclusions</p> <p>A mini-Tn<it>7 </it>system was employed for rapid and reliable engineering of <it>E. coli </it>and <it>S. enterica </it>serovar Typhimurium host strains for plasmids containing <it>ori</it>_R6Kγ. Since mini-Tn7 elements transpose in most, if not all, Gram negative bacteria, we anticipate that with relatively minor modifications this newly established method will for the first time allow engineering of other bacterial species to enable replication of plasmids with <it>ori</it>_R6Kγ.</p

WISE/NEOWISE observations of Active Bodies in the Main Belt

We report results based on mid-infrared photometry of 5 active main belt objects (AMBOs) detected by the Wide-field Infrared Survey Explorer (WISE) spacecraft. Four of these bodies, P/2010 R2 (La Sagra), 133P/Elst-Pizarro, (596) Scheila, and 176P/LINEAR, showed no signs of activity at the time of the observations, allowing the WISE detections to place firm constraints on their diameters and albedos. Geometric albedos were in the range of a few percent, and on the order of other measured comet nuclei. P/2010 A2 was observed on April 2-3, 2010, three months after its peak activity. Photometry of the coma at 12 and 22 {\mu}m combined with ground-based visible-wavelength measurements provides constraints on the dust particle mass distribution (PMD), dlogn/dlogm, yielding power-law slope values of {\alpha} = -0.5 +/- 0.1. This PMD is considerably more shallow than that found for other comets, in particular inbound particle fluence during the Stardust encounter of comet 81P/Wild 2. It is similar to the PMD seen for 9P/Tempel 1 in the immediate aftermath of the Deep Impact experiment. Upper limits for CO2 & CO production are also provided for each AMBO and compared with revised production numbers for WISE observations of 103P/Hartley 2.Comment: 32 Pages, including 5 Figure

The Sloan Digital Sky Survey-II Supernova Survey: Search Algorithm and Follow-up Observations

The Sloan Digital Sky Survey-II Supernova Survey has identified a large number of new transient sources in a 300 sq. deg. region along the celestial equator during its first two seasons of a three-season campaign. Multi-band (ugriz) light curves were measured for most of the sources, which include solar system objects, Galactic variable stars, active galactic nuclei, supernovae (SNe), and other astronomical transients. The imaging survey is augmented by an extensive spectroscopic follow-up program to identify SNe, measure their redshifts, and study the physical conditions of the explosions and their environment through spectroscopic diagnostics. During the survey, light curves are rapidly evaluated to provide an initial photometric type of the SNe, and a selected sample of sources are targeted for spectroscopic observations. In the first two seasons, 476 sources were selected for spectroscopic observations, of which 403 were identified as SNe. For the Type Ia SNe, the main driver for the Survey, our photometric typing and targeting efficiency is 90%. Only 6% of the photometric SN Ia candidates were spectroscopically classified as non-SN Ia instead, and the remaining 4% resulted in low signal-to-noise, unclassified spectra. This paper describes the search algorithm and the software, and the real-time processing of the SDSS imaging data. We also present the details of the supernova candidate selection procedures and strategies for follow-up spectroscopic and imaging observations of the discovered sources.Comment: Accepted for publication in The Astronomical Journal (66 pages, 13 figures); typos correcte