Standard survey methods for estimating colony losses and explanatory risk factors in Apis mellifera

This chapter addresses survey methodology and questionnaire design for the collection of data pertaining to estimation of honey bee colony loss rates and identification of risk factors for colony loss. Sources of error in surveys are described. Advantages and disadvantages of different random and non-random sampling strategies and different modes of data collection are presented to enable the researcher to make an informed choice. We discuss survey and questionnaire methodology in some detail, for the purpose of raising awareness of issues to be considered during the survey design stage in order to minimise error and bias in the results. Aspects of survey design are illustrated using surveys in Scotland. Part of a standardized questionnaire is given as a further example, developed by the COLOSS working group for Monitoring and Diagnosis. Approaches to data analysis are described, focussing on estimation of loss rates. Dutch monitoring data from 2012 were used for an example of a statistical analysis with the public domain R software. We demonstrate the estimation of the overall proportion of losses and corresponding confidence interval using a quasi-binomial model to account for extra-binomial variation. We also illustrate generalized linear model fitting when incorporating a single risk factor, and derivation of relevant confidence intervals

Essential Oils from Artemisia herba alba Asso., Maticaria Recutita L., and Dittrichia Viscosa L. (Asteraceae): A Promising Source of Eco-Friendly Agents to Control Callosobruchus maculatus Fab. Warehouse Pest

Callosobruchus maculatus (Fab.) (C. maculatus) is one of the major pests of legume seeds in storage causing significant damage, leading to food insecurity and low income for farmers. This work was planned to develop eco-friendly agents from essential oils of Artemisia herba alba Asso. (AEO), Maticaria Recutita L. (MEO), and Dittrichia Viscosa L. (DEO) to control C. maculatus. To achieve this goal, essential oils (EOs) were extracted by hydro-distillation using Clevenger apparatus before being characterized by GC-MS. EOs were used for testing purposes using three different tests, namely, inhalation toxicity, contact toxicity, and repellency tests. GC-MS analysis of EOs showed the presence of 16 potentially active compounds in AEO and 38 in MEO, whilst 15 compounds were identified in DEO. AEO was higher in thujone (57.6%) and chrysanthenone (11.8%). Santolina alcohol (40.7%) and germacrene D (8.9%) were the major compounds identified in MEO, whereas isocostic acid (72.3%) was the chief compound of DEO. The obtained findings showed that the studied EOs showed considerable insecticidal activity against C. maculatus with a lethal dose (LC50) of 3.78, 8.86, and 14.34 μL/1 liter of air by AEO, MEO, and DEO, respectively. At 1 μL/1 liter of air, the oviposition reduction rate was 90.02%, 70.65%, and 48.23% by AEO, MEO, and DEO, respectively, whereas the emergence reduction rate was 87.32%, 60.08%, and 32.24% by AEO, MEO, and DEO, respectively. With increasing doses up to 20 μL/L, the reduction of individual emergence reached 98.8% by AEO of 24 h after treatment. AEO, MEO, and DEO showed significant repellent effects against adults of C. maculatus with repulsion percentages of 60.83%, 50.83%, and 72.5%, respectively. The outcome of this work suggests that the essential oils of the studied plants, particularly Artemisia herba alba Asso. oils, can constitute a natural and environmentally friendly alternative to develop new bioinsecticides for the control of C. maculatus.</jats:p

Genome-Wide Association Study of Schizophrenia in Japanese Population

Schizophrenia is a devastating neuropsychiatric disorder with genetically complex traits. Genetic variants should explain a considerable portion of the risk for schizophrenia, and genome-wide association study (GWAS) is a potentially powerful tool for identifying the risk variants that underlie the disease. Here, we report the results of a three-stage analysis of three independent cohorts consisting of a total of 2,535 samples from Japanese and Chinese populations for searching schizophrenia susceptibility genes using a GWAS approach. Firstly, we examined 115,770 single nucleotide polymorphisms (SNPs) in 120 patient-parents trio samples from Japanese schizophrenia pedigrees. In stage II, we evaluated 1,632 SNPs (1,159 SNPs of p<0.01 and 473 SNPs of p<0.05 that located in previously reported linkage regions). The second sample consisted of 1,012 case-control samples of Japanese origin. The most significant p value was obtained for the SNP in the ELAVL2 [(embryonic lethal, abnormal vision, Drosophila)-like 2] gene located on 9p21.3 (p = 0.00087). In stage III, we scrutinized the ELAVL2 gene by genotyping gene-centric tagSNPs in the third sample set of 293 family samples (1,163 individuals) of Chinese descent and the SNP in the gene showed a nominal association with schizophrenia in Chinese population (p = 0.026). The current data in Asian population would be helpful for deciphering ethnic diversity of schizophrenia etiology

Association of the MTHFR A1298C Variant with Unexplained Severe Male Infertility

The methylenetetrahydrofolate reductase (MTHFR) gene is one of the main regulatory enzymes involved in folate metabolism, DNA synthesis and remethylation reactions. The influence of MTHFR variants on male infertility is not completely understood. The objective of this study was to analyze the distribution of the MTHFR C677T and A1298C variants using PCR-Restriction Fragment Length Polymorphism (RFLP) in a case group consisting of 344 men with unexplained reduced sperm counts compared to 617 ancestry-matched fertile or normozoospermic controls. The Chi square test was used to analyze the genotype distributions of MTHFR polymorphisms. Our data indicated a lack of association of the C677T variant with infertility. However, the homozygous (C/C) A1298C polymorphism of the MTHFR gene was present at a statistically high significance in severe oligozoospermia group compared with controls (OR = 3.372, 95% confidence interval CI = 1.27–8.238; p = 0.01431). The genotype distribution of the A1298C variants showed significant deviation from the expected Hardy-Weinberg equilibrium, suggesting that purifying selection may be acting on the 1298CC genotype. Further studies are necessary to determine the influence of the environment, especially the consumption of diet folate on sperm counts of men with different MTHFR variants

A Genome-Wide Screen for Genetic Variants That Modify the Recruitment of REST to Its Target Genes

Increasing numbers of human diseases are being linked to genetic variants, but our understanding of the mechanistic links leading from DNA sequence to disease phenotype is limited. The majority of disease-causing nucleotide variants fall within the non-protein-coding portion of the genome, making it likely that they act by altering gene regulatory sequences. We hypothesised that SNPs within the binding sites of the transcriptional repressor REST alter the degree of repression of target genes. Given that changes in the effective concentration of REST contribute to several pathologies—various cancers, Huntington's disease, cardiac hypertrophy, vascular smooth muscle proliferation—these SNPs should alter disease-susceptibility in carriers. We devised a strategy to identify SNPs that affect the recruitment of REST to target genes through the alteration of its DNA recognition element, the RE1. A multi-step screen combining genetic, genomic, and experimental filters yielded 56 polymorphic RE1 sequences with robust and statistically significant differences of affinity between alleles. These SNPs have a considerable effect on the the functional recruitment of REST to DNA in a range of in vitro, reporter gene, and in vivo analyses. Furthermore, we observe allele-specific biases in deeply sequenced chromatin immunoprecipitation data, consistent with predicted differenes in RE1 affinity. Amongst the targets of polymorphic RE1 elements are important disease genes including NPPA, PTPRT, and CDH4. Thus, considerable genetic variation exists in the DNA motifs that connect gene regulatory networks. Recently available ChIP–seq data allow the annotation of human genetic polymorphisms with regulatory information to generate prior hypotheses about their disease-causing mechanism

Lichenological exploration of Algeria: historical overview and annotated bibliography, 1799-2013

yesDespite more than two centuries of almost uninterrupted surveys and studies of Algerian lichenology, the history and lichen diversity of Algeria are still poorly understood. During the preparation of a forthcoming checklist of Algerian lichens it was considered necessary to provide the present historical overview of lichenological exploration of the country from 1799 to 2013, supported by a reasonably comprehensive annotated bibliography of 171 titles