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WORKPLACE COMMUNICATION: EXAMINING LEADER-MEMBER EXCHANGE THEORY, UNCERTAINTY AVOIDANCE, AND SOCIAL STYLES
There are numerous books, articles, and papers written about communicating in the work environment; especially how to communicate to the work force at large. However, not much is written or studied concerning the dyadic communication between supervisor and subordinate. The paper will use leader-member exchange theory (LMX) as a basis for communication between supervisor and subordinate. LMX gives steps to aid in the communication process and helps guide the relationship between a supervisor and subordinate; however, there are two other elements in need of attention. In order to communicate effectively with their subordinates, supervisors need an understanding of the subordinates’ social-styles and uncertainty avoidance level. With a full understanding of these two individualistic elements, supervisors will be able to adjust their communication social style and frequency of dialogue to use LMX in building a lasting workplace relationship
Comparison of synthetic membranes in the development of an in vitro feeding system for Dermanyssus gallinae
Although artificial feeding models for the poultry red mite (Dermanyssus gallinae) most frequently use biological membranes consisting of day-old chick skin, there are ethical considerations associated with the use of skin. The few studies reported in the literature that have investigated the use of synthetic membranes to feed D. gallinae in vitro have reported limited success. The current study describes an investigation into the use of synthetic membranes made from either Nescofilm® or rayon and silicone, used either alone or in combination with different feather or skin extracts, as well as the use of capillary tubes. In all, 12 different treatments were used, and the feeding rate of D. gallinae was compared to that of day-old chick skin. Allowing mites to feed on a membrane consisting of Nescofilm with a skin extract resulted in the highest proportion of mites feeding (32.3%), which was not significantly different to the feeding rate of mites on day-old chick skin (38.8%). This study confirms that synthetic membranes can be used to feed D. gallinae artificially. Further optimization of the membrane and mite storage conditions is still necessary, but the study demonstrates a proof of concept
Validation of a multilocus genotyping scheme for subtyping Cryptosporidium parvum for epidemiological purposes
We would like to thank Prof. Giovanni Widmer and Dr. Willie Weir for their helpful advice on data analysis and Dr. Harriet Risby for her assistance with the manuscript formatting and additional laboratory testing. This work was part funded by the European Union Seventh Framework Programme ( [FP7/2007-2013] [FP7/2007-2011] under Grant agreement no: 311846) .Subtyping Cryptosporidium parvum for outbreak investigations or epidemiological surveillance
usually relies on DNA sequence analysis of a gene coding for a 60 KDa glycoprotein (gp60).
Although gp60 can be useful for allelic discrimination and to help investigate sources and routes
of transmission, the presence of common subtypes and recombination during the parasite's sexual
life-cycle demand a multilocus-based method for more discriminatory genotyping. While whole
genome sequencing would provide the ultimate approach, it is a time consuming and expensive
option for faecal parasites such as Cryptosporidium that occur at low density and are difficult to
propagate routinely. In this study, we selected and evaluated a panel of previously identified
variable-number tandem-repeat (VNTR) markers, to establish a multilocus genotyping scheme
based on fragment sizing, appropriate for inter-laboratory surveillance and outbreak investigations.
Seven VNTR markers were validated in vitro and demonstrated typeability of 0.85
and discriminatory power of 0.99. The discriminatory power was much greater than the currently
used gp60 sequencing (0.74), which identified 26 subtypes, compared to 100 different MLVA
profiles within the same sample set. The assay was robust, with repeatable results and reproducibility
across three laboratories demonstrating the scheme was suitable for inter-laboratory
comparison of C. parvum subtypes. As the majority of genotypes (79%) were unique among
epidemiologically unrelated samples, there was efficiency to infer linkage, and epidemiological
concordance was observed in historical outbreaks. We propose that the multilocus variable
number of tandem repeats analysis scheme is suitable to assist outbreak investigations.European Commission 31184
Swimming Pool-Related Outbreak of a Rare gp60 Subtype of Cryptosporidium hominis, England, October 2016
In October 2016, Public Health England was initially notified of four cases of cryptosporidiosis among users of two swimming pools. We investigated to identify further cases, the outbreak source, and ensure the implementation of appropriate control measures. Probable primary cases had diarrhoea and reported swimming in the pools 1–12 days prior to illness; confirmed cases were verified by the reference laboratory. Secondary cases had contact with primary cases 1–12 days prior to illness. We identified twenty-two cases: eleven were primary (eight confirmed) and eleven were secondary (five confirmed). Four cases were infected with C. parvum (different gp60 subtypes); all were primary and swam at two pools. Seven primary and secondary cases were infected with C. hominis gp60 subtype IdA16, and all were associated one pool. Failings in pool water treatment and management were identified that likely contributed to the load on the filters and their efficiency. Our investigation identified a complex outbreak, with secondary transmission, involving exposures to two swimming pools. C. hominis IdA16 is rare; it has been isolated from only three previous UK cases. We hypothesize that C. hominis cases arose from a common exposure, and the C. parvum cases were likely sporadic. This investigation highlights the value of integrating epidemiology and microbiology to investigate clusters of Cryptosporidium cases, defining the extent of the outbreak and the likely transmission pathways
Sporadic Human Cryptosporidiosis Caused by Cryptosporidium cuniculus, United Kingdom, 2007–2008
To investigate sporadic human cryptosporidiosis trends in the United Kingdom, we tested 3,030 Cryptosporidium spp.–positive fecal samples, submitted for routine typing in 2007–2008, for C. cuniculus. C. cuniculus prevalence was 1.2%; cases were mostly indigenous and occurred across all age groups. Most occurred during August–October and may be linked to exposure opportunities
Lamellar orientation of block copolymer using polarity switch of Nitrophenyl self-assembled monolayer (SAM) induced by electron beam.
Direct sequencing of Cryptosporidium in stool samples for public health
The protozoan parasite Cryptosporidium is an important cause of diarrheal disease (cryptosporidiosis) in humans and animals, with significant morbidity and mortality especially in severely immunocompromised people and in young children in low-resource settings. Due to the sexual life cycle of the parasite, transmission is complex. There are no restrictions on sexual recombination between sub-populations, meaning that large-scale genetic recombination may occur within a host, potentially confounding epidemiological analysis. To clarify the relationships between infections in different hosts, it is first necessary to correctly identify species and genotypes, but these differentiations are not made by standard diagnostic tests and more sophisticated molecular methods have been developed. For instance, multilocus genotyping has been utilized to differentiate isolates within the major human pathogens, Cryptosporidium parvum and Cryptosporidium hominis. This has allowed mixed populations with multiple alleles to be identified: recombination events are considered to be the driving force of increased variation and the emergence of new subtypes. As yet, whole genome sequencing (WGS) is having limited impact on public health investigations, due in part to insufficient numbers of oocysts and purity of DNA derived from clinical samples. Moreover, because public health agencies have not prioritized parasites, validation has not been performed on user-friendly data analysis pipelines suitable for public health practitioners. Nonetheless, since the first whole genome assembly in 2004 there are now numerous genomes of human and animal-derived cryptosporidia publically available, spanning nine species. It has also been demonstrated that WGS from very low numbers of oocysts is possible, through the use of amplification procedures. These data and approaches are providing new insights into host-adapted infectivity, the presence and frequency of multiple sub-populations of Cryptosporidium spp. within single clinical samples, and transmission of infection. Analyses show that although whole genome sequences do indeed contain many alleles, they are invariably dominated by a single highly abundant allele. These insights are helping to better understand population structures within hosts, which will be important to develop novel prevention strategies in the fight against cryptosporidiosis
New frontiers in agricultural geography: transformations, food security, land grabs and climate change
Agriculture as a central focus of study featured prominently at several different times in the historical development of human geography, but it has also been an important contributor to the disciplinary transformation that has occurred since 1970. This essay outlines this more recent history, arguing that agricultural geography developed its own concepts and concerns, paralleling some of those within the wider discipline. It illustrates how in the past two decades attempts to examine changes occurring across the breadth of the agri-food system (from supply, to production, to consumption) have brought about a more issues-focused agricultural geography. There is discussion of the use of broad overarching concepts, which have conceived of changes to agriculture and the agri-food system in terms of episodic developments. This has seen recognition of different food regimes, acknowledging possible transitions from productivism to post-productivism to multifunctionality and perhaps neo-productivism. Having discussed these concepts, drawing extensively upon literature written in English, the essay then focuses on selected major problems or key issues to which agriciultural geographers are currently contributing new insights, namely the closely related topics of food security, land grabs and adaptations to climate change
Investigating the public health significance of Cryptosporidium in the environment
The high-resolution molecular characterisation of the Cryptosporidium species and subtypes biquitous in environmental samples can provide important information regarding their potential public health significance. The purpose of this study was to develop, evaluate and apply sensitive screening and DNA recovery methods to environmental Cryptosporidium for molecular characterisation. A systemic literature review as undertaken to identify methods of subtyping Cryptosporidium species recovered from environmental samples. Prior to molecular characterisation, the recovery and detection of oocysts from water is by immunomagnetic separation and immunofluorescence microscopy. However, this method is not currently suited for screening large numbers of faecal samples. A commercially available faecal parasite concentrator protocol was modified and evaluated for the enhanced detection of Cryptosporidium oocysts. Once recovered from samples, DNA must be released from the oocyst bound sporozoites before molecular methods can be applied. Commonly used oocyst disruption methods were identified and using samples containing high numbers of oocysts, evaluated by microscopy and a SYBR Green real-time polymerase chain reaction (PCR) developed from the internal stage of a previously published nested small subunit ribosomal DNA PCR. The eight best methods were then evaluated with low numbers of oocysts in the presence of immunomagnetic beads to replicate field samples, using the published nested PCR and SYBR Green real-time PCR. The enhanced screening and optimal DAN recovery combined with microsatellite multilocus fragment analysis was applied in a study investigating the species and subtypes of Cryptosporidium recovered from water, non-clinical farmed and wild animal faeces as well as clinical human and cattle samples from within a single water catchment. Several human pathogenic Cryptosporidium subtypes were identified in addition to the unprecedented finding of Cryptosporidium as the predominant species in the catchment surface water. This study demonstrated the potential application of the developed methodology in the public health investigation of environmental Cryptosporidium
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