Movements of Wolves at the Northern Extreme of the Species' Range, Including during Four Months of Darkness

Information about wolf (Canis lupus) movements anywhere near the northern extreme of the species' range in the High Arctic (>75°N latitude) are lacking. There, wolves prey primarily on muskoxen (Ovibos moschatus) and must survive 4 months of 24 hr/day winter darkness and temperatures reaching −53 C. The extent to which wolves remain active and prey on muskoxen during the dark period are unknown, for the closest area where information is available about winter wolf movements is >2,250 km south. We studied a pack of ≥20 wolves on Ellesmere Island, Nunavut, Canada (80°N latitude) from July 2009 through mid-April 2010 by collaring a lead wolf with a Global Positioning System (GPS)/Argos radio collar. The collar recorded the wolf's precise locations at 6:00 a.m. and 6:00 p.m. daily and transmitted the locations by satellite to our email. Straight-line distances between consecutive 12-hr locations varied between 0 and 76 km. Mean (SE) linear distance between consecutive locations (n = 554) was 11 (0.5) km. Total minimum distance traveled was 5,979 km, and total area covered was 6,640 km2, the largest wolf range reported. The wolf and presumably his pack once made a 263-km (straight-line distance) foray to the southeast during 19–28 January 2010, returning 29 January to 1 February at an average of 41 km/day straight-line distances between 12-hr locations. This study produced the first detailed movement information about any large mammal in the High Arctic, and the average movements during the dark period did not differ from those afterwards. Wolf movements during the dark period in the highest latitudes match those of the other seasons and generally those of wolves in lower latitudes, and, at least with the gross movements measurable by our methods, the 4-month period without direct sunlight produced little change in movements

Degenerate and Other Neutrino Mass Scenarios and Dark Matter

I discuss in this talk mainly three topics related with dark matter motivated neutrino mass spectrum and a generic issue of mass pattern, the normal versus the inverted mass hierarchies. In the first part, by describing failure of a nontrivial potential counter example, I argue that the standard 3 $\nu$ mixing scheme with the solar and the atmospheric $\Delta m^2$'s is robust. In the second part, I discuss the almost degenerate neutrino (ADN) scenario as the unique possibility of accommodating dark matter mass neutrinos into the 3 $\nu$ scheme. I review a cosmological bound and then reanalyze the constraints imposed on the ADN scenario with the new data of double beta decay experiment. In the last part, I discuss the 3 $\nu$ flavor transformation in supernova (SN) and point out the possibility that neutrinos from SN may distinguish the normal versus inverted hierarchies of neutrino masses. By analyzing the neutrino data from SN1987A, I argue that the inverted mass hierarchy is disfavored by the data

The impact of measurement errors in the identification of regulatory networks

<p>Abstract</p> <p>Background</p> <p>There are several studies in the literature depicting measurement error in gene expression data and also, several others about regulatory network models. However, only a little fraction describes a combination of measurement error in mathematical regulatory networks and shows how to identify these networks under different rates of noise.</p> <p>Results</p> <p>This article investigates the effects of measurement error on the estimation of the parameters in regulatory networks. Simulation studies indicate that, in both time series (dependent) and non-time series (independent) data, the measurement error strongly affects the estimated parameters of the regulatory network models, biasing them as predicted by the theory. Moreover, when testing the parameters of the regulatory network models, p-values computed by ignoring the measurement error are not reliable, since the rate of false positives are not controlled under the null hypothesis. In order to overcome these problems, we present an improved version of the Ordinary Least Square estimator in independent (regression models) and dependent (autoregressive models) data when the variables are subject to noises. Moreover, measurement error estimation procedures for microarrays are also described. Simulation results also show that both corrected methods perform better than the standard ones (i.e., ignoring measurement error). The proposed methodologies are illustrated using microarray data from lung cancer patients and mouse liver time series data.</p> <p>Conclusions</p> <p>Measurement error dangerously affects the identification of regulatory network models, thus, they must be reduced or taken into account in order to avoid erroneous conclusions. This could be one of the reasons for high biological false positive rates identified in actual regulatory network models.</p

Do Lions Panthera leo Actively Select Prey or Do Prey Preferences Simply Reflect Chance Responses via Evolutionary Adaptations to Optimal Foraging?

Research on coursing predators has revealed that actions throughout the predatory behavioral sequence (using encounter rate, hunting rate, and kill rate as proxy measures of decisions) drive observed prey preferences. We tested whether similar actions drive the observed prey preferences of a stalking predator, the African lion Panthera leo. We conducted two 96 hour, continuous follows of lions in Addo Elephant National Park seasonally from December 2003 until November 2005 (16 follows), and compared prey encounter rate with prey abundance, hunt rate with prey encounter rate, and kill rate with prey hunt rate for the major prey species in Addo using Jacobs' electivity index. We found that lions encountered preferred prey species far more frequently than expected based on their abundance, and they hunted these species more frequently than expected based on this higher encounter rate. Lions responded variably to non-preferred and avoided prey species throughout the predatory sequence, although they hunted avoided prey far less frequently than expected based on the number of encounters of them. We conclude that actions of lions throughout the predatory behavioural sequence, but particularly early on, drive the prey preferences that have been documented for this species. Once a hunt is initiated, evolutionary adaptations to the predator-prey interactions drive hunting success

The Highly Virulent 2006 Norwegian EHEC O103:H25 Outbreak Strain Is Related to the 2011 German O104:H4 Outbreak Strain

In 2006, a severe foodborne EHEC outbreak occured in Norway. Seventeen cases were recorded and the HUS frequency was 60%. The causative strain, Esherichia coli O103:H25, is considered to be particularly virulent. Sequencing of the outbreak strain revealed resemblance to the 2011 German outbreak strain E. coli O104:H4, both in genome and Shiga toxin 2-encoding (Stx2) phage sequence. The nucleotide identity between the Stx2 phages from the Norwegian and German outbreak strains was 90%. During the 2006 outbreak, stx2-positive O103:H25 E. coli was isolated from two patients. All the other outbreak associated isolates, including all food isolates, were stx-negative, and carried a different phage replacing the Stx2 phage. This phage was of similar size to the Stx2 phage, but had a distinctive early phage region and no stx gene. The sequence of the early region of this phage was not retrieved from the bacterial host genome, and the origin of the phage is unknown. The contaminated food most likely contained a mixture of E. coli O103:H25 cells with either one of the phages

Drosophila Dynein Intermediate Chain Gene, Dic61B, Is Required for Spermatogenesis

This study reports the identification and characterization of a novel gene, Dic61B, required for male fertility in Drosophila. Complementation mapping of a novel male sterile mutation, ms21, isolated in our lab revealed it to be allelic to CG7051 at 61B1 cytogenetic region, since two piggyBac insertion alleles, CG7051c05439 and CG7051f07138 failed to complement. CG7051 putatively encodes a Dynein intermediate chain. All three mutants, ms21, CG7051c05439 and CG7051f07138, exhibited absolute recessive male sterility with abnormally coiled sperm axonemes causing faulty sperm individualization as revealed by Phalloidin staining in Don Juan-GFP background. Sequencing of PCR amplicons uncovered two point mutations in ms21 allele and confirmed the piggyBac insertions in CG7051c05439 and CG7051f07138 alleles to be in 5′UTR and 4th exon of CG7051 respectively, excision of which reverted the male sterility. In situ hybridization to polytene chromosomes demonstrated CG7051 to be a single copy gene. RT-PCR of testis RNA revealed defective splicing of the CG7051 transcripts in mutants. Interestingly, expression of cytoplasmic dynein intermediate chain, α, β, γ tubulins and α-spectrin was normal in mutants while ultra structural studies revealed defects in the assembly of sperm axonemes. Bioinformatics further highlighted the homology of CG7051 to axonemal dynein intermediate chain of various organisms, including DNAI1 of humans, mutations in which lead to male sterility due to immotile sperms. Based on these observations we conclude that CG7051 encodes a novel axonemal dynein intermediate chain essential for male fertility in Drosophila and rename it as Dic61B. This is the first axonemal Dic gene of Drosophila to be characterized at molecular level and shown to be required for spermatogenesis

Developing an agenda for research about policies to improve access to healthy foods in rural communities: a concept mapping study

Background Policies that improve access to healthy, affordable foods may improve population health and reduce health disparities. In the United States most food access policy research focuses on urban communities even though residents of rural communities face disproportionately higher risk for nutrition-related chronic diseases compared to residents of urban communities. The purpose of this study was to (1) identify the factors associated with access to healthy, affordable food in rural communities in the United States; and (2) prioritize a meaningful and feasible rural food policy research agenda. Methods This study was conducted by the Rural Food Access Workgroup (RFAWG), a workgroup facilitated by the Nutrition and Obesity Policy Research and Evaluation Network. A national sample of academic and non-academic researchers, public health and cooperative extension practitioners, and other experts who focus on rural food access and economic development was invited to complete a concept mapping process that included brainstorming the factors that are associated with rural food access, sorting and organizing the factors into similar domains, and rating the importance of policies and research to address these factors. As a last step, RFAWG members convened to interpret the data and establish research recommendations. Results Seventy-five participants in the brainstorming exercise represented the following sectors: non-extension research (n = 27), non-extension program administration (n = 18), “other� (n = 14), policy advocacy (n = 10), and cooperative extension service (n = 6). The brainstorming exercise generated 90 distinct statements about factors associated with rural food access in the United States; these were sorted into 5 clusters. Go Zones were established for the factors that were rated highly as both a priority policy target and a priority for research. The highest ranked policy and research priorities include strategies designed to build economic viability in rural communities, improve access to federal food and nutrition assistance programs, improve food retail systems, and increase the personal food production capacity of rural residents. Respondents also prioritized the development of valid and reliable research methodologies to measure variables associated with rural food access. Conclusions This collaborative, trans-disciplinary, participatory process, created a map to guide and prioritize research about polices to improve healthy, affordable food access in rural communities

Packages of Care for Alcohol Use Disorders in Low- And Middle-Income Countries

In the fourth in a series of six articles on packages of care for mental disorders in low- and middle-income countries, Vivek Benegal and colleagues discuss the treatment of alcohol use disorders

Literature Mining for the Discovery of Hidden Connections between Drugs, Genes and Diseases

The scientific literature represents a rich source for retrieval of knowledge on associations between biomedical concepts such as genes, diseases and cellular processes. A commonly used method to establish relationships between biomedical concepts from literature is co-occurrence. Apart from its use in knowledge retrieval, the co-occurrence method is also well-suited to discover new, hidden relationships between biomedical concepts following a simple ABC-principle, in which A and C have no direct relationship, but are connected via shared B-intermediates. In this paper we describe CoPub Discovery, a tool that mines the literature for new relationships between biomedical concepts. Statistical analysis using ROC curves showed that CoPub Discovery performed well over a wide range of settings and keyword thesauri. We subsequently used CoPub Discovery to search for new relationships between genes, drugs, pathways and diseases. Several of the newly found relationships were validated using independent literature sources. In addition, new predicted relationships between compounds and cell proliferation were validated and confirmed experimentally in an in vitro cell proliferation assay. The results show that CoPub Discovery is able to identify novel associations between genes, drugs, pathways and diseases that have a high probability of being biologically valid. This makes CoPub Discovery a useful tool to unravel the mechanisms behind disease, to find novel drug targets, or to find novel applications for existing drugs