8,144 research outputs found

    Intended or unintended strategy? The activities of middle managers in strategy implementation

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    When top managers task middle managers with implementing strategies, those strategies are often executed in a deviated form, which leads to the creation of unintended strategies. Despite much research on middle managers and their role and behaviors in strategy implementation, there is still only a limited understanding of the implementation activities that result in intended and unintended strategies. Using a strategy-as-practice perspective and interviews with 40 middle managers about 122 strategy implementations, we investigate strategy implementation activities and develop a model of middle manager activities in strategy implementation. We find that seven of the ten activities differ in frequency between intended and unintended strategies. This study extends the strategy implementation literature by conceptualizing a critical link in how different strategy implementation outcomes come about. We also broaden the middle management perspective in strategy by extending the range of activities that explain middle managers’ engagement with strategy and differentiating them across two strategy implementation outcomes

    Structural modeling and functional analysis of the essential ribosomal processing protease Prp from Staphylococcus aureus

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    In Firmicutes and related bacteria, ribosomal large subunit protein L27 is encoded with a conserved N-terminal extension that is removed to expose residues critical for ribosome function. Bacteria encoding L27 with this N-terminal extension also encode a sequence-specific cysteine protease, Prp, which carries out this cleavage. In this work, we demonstrate that L27 variants with an un-cleavable N-terminal extension, or lacking the extension (pre-cleaved), are unable to complement an L27 deletion in Staphylococcus aureus. This indicates that N-terminal processing of L27 is not only essential but possibly has a regulatory role. Prp represents a new clade of previously uncharacterized cysteine proteases, and the dependence of S. aureus on L27 cleavage by Prp validates the enzyme as a target for potential antibiotic development. To better understand the mechanism of Prp activity, we analyzed Prp enzyme kinetics and substrate preference using a fluorogenic peptide cleavage assay. Molecular modeling and site-directed mutagenesis implicate several residues around the active site in catalysis and substrate binding, and support a structural model in which rearrangement of a flexible loop upon binding of the correct peptide substrate is required for the active site to assume the proper conformation. These findings lay the foundation for the development of antimicrobials that target this novel, essential pathway

    Bluetongue virus infection creates light averse Culicoides vectors and serious errors in transmission risk estimates.

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    BackgroundPathogen manipulation of host behavior can greatly impact vector-borne disease transmission, but almost no attention has been paid to how it affects disease surveillance. Bluetongue virus (BTV), transmitted by Culicoides biting midges, is a serious disease of ruminant livestock that can cause high morbidity and mortality and significant economic losses. Worldwide, the majority of surveillance for Culicoides to assess BTV transmission risk is done using UV-light traps. Here we show that field infection rates of BTV are significantly lower in midge vectors collected using traps baited with UV light versus a host cue (CO2).MethodsWe collected Culicoides sonorensis midges in suction traps baited with CO2, UV-light, or CO2 + UV on three dairies in southern California to assess differences in the resulting estimated infection rates from these collections. Pools of midges were tested for BTV by qRT-PCR, and maximum likelihood estimates of infection rate were calculated by trap. Infection rate estimates were also calculated by trapping site within a dairy. Colonized C. sonorensis were orally infected with BTV, and infection of the structures of the compound eye was examined using structured illumination microscopy.ResultsUV traps failed entirely to detect virus both early and late in the transmission season, and underestimated virus prevalence by as much as 8.5-fold. CO2 + UV traps also had significantly lower infection rates than CO2-only traps, suggesting that light may repel infected vectors. We found very high virus levels in the eyes of infected midges, possibly causing altered vision or light perception. Collecting location also greatly impacts our perception of virus activity.ConclusionsBecause the majority of global vector surveillance for bluetongue uses only light-trapping, transmission risk estimates based on these collections are likely severely understated. Where national surveillance programs exist, alternatives to light-trapping should be considered. More broadly, disseminated infections of many arboviruses include infections in vectors' eyes and nervous tissues, and this may be causing unanticipated behavioral effects. Field demonstrations of pathogen-induced changes in vector behavior are quite rare, but should be studied in more systems to accurately predict vector-borne disease transmission

    Consumption of Coconut Oil (Cocos Nucifera ) on Sperm Parameters of Adult Albino Wistar Rats

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    This study was aimed at assessing the possible effects coconut oil could have on the sperm parameters of albino rats. Twenty adult male Wistar rats randomly divided into four (4) groups of five rats each were investigated. The control group received normal saline and experimental groups; Low Dose (LD), Moderate Dose (MD) and High Dose (HD) received coconut oil extract of 0.5ml/kg b.w, 1.1ml/kg b.w and 2.2ml/kg b.w respectively for fourteen days via orogastric tube. On day 14 of the experiment, the rats were euthanized under chloroform vapour and sacrificed and testes excised. There was an insignificant decrease (p<0.05) in mean testicular weight of the treated rats; LD (1.14±0.05), MD (1.16±0.05) and HD (1.12±0.06) groups compared to the control rats (1.20±0.04). Sperm count was increased significantly (p<0.05) in the animals administered with coconut oil; LD (39.72±0.28x106/ml), MD (46.76±1.46x106/ml), HD (68.18±0.39x106/ml) in comparison with animals in the control group (35.28±0.34x106/ml). Sperm motility increased significantly (p<0.05) in animals of the HD group (55.00±1.58%) compared to what was observed in rats found in LD (37.60±0.81%) and MD groups (45.00±0.84%). The HD group recorded (85.00±0.71%) sperm viability, a significant increase (p<0.05) compared to that of the control group (75.60±0.93%). Sperms with normal morphology were significantly increased (p<0.05) in LD (75.60±0.68%), MD (76.00±1.87%) and HD (87.20±0.86%) compared to the control group (69.00±1.22%). Coconut oil has no deleterious effect on the sperm parameters and can lead to enhanced spermatogenesis. Keywords: Cocos nucifera, sperm parameters, coconut oil DOI: 10.7176/JBAH/9-14-06 Publication date:July 31st 201

    The pyloric neural circuit of the herbivorous crab Pugettia producta shows limited sensitivity to several neuromodulators that elicit robust effects in more opportunistically feeding decapods

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    Modulation of neural circuits in the crustacean stomatogastric nervous system (STNS) allows flexibility in the movements of the foregut musculature. The extensive repertoire of such resulting motor patterns in dietary generalists is hypothesized to permit these animals to process varied foods. The foregut and STNS of Pugettia producta are similar to those of other decapods, but its diet is more uniform, consisting primarily of kelp. We investigated the distribution of highly conserved neuromodulators in the stomatogastric ganglion (STG) and neuroendocrine organs of Pugettia, and documented their effects on its pyloric rhythm. Using immunohistochemistry, we found that the distributions of Cancer borealis tachykinin-related peptide I (CabTRP I), crustacean cardioactive peptide (CCAP), proctolin, red pigment concentrating hormone (RPCH) and tyrosine hydroxylase (dopamine) were similar to those of other decapods. For all peptides except proctolin, the isoforms responsible for the immunoreactivity were confirmed by mass spectrometry to be the authentic peptides. Only two modulators had physiological effects on the pyloric circuit similar to those seen in other species. In non-rhythmic preparations, proctolin and the muscarinic acetylcholine agonist oxotremorine consistently initiated a full pyloric rhythm. Dopamine usually activated a pyloric rhythm, but this pattern was highly variable. In only about 25% of preparations, RPCH activated a pyloric rhythm similar to that seen in other species. CCAP and CabTRP I had no effect on the pyloric rhythm. Thus, whereas Pugettia possesses all the neuromodulators investigated, its pyloric rhythm, when compared with other decapods, appears less sensitive to many of them, perhaps because of its limited diet

    Seasonal variation and impact of waste-water lagoons as larval habitat on the population dynamics of Culicoides sonorensis (Diptera:Ceratpogonidae) at two dairy farms in northern California.

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    The Sacramento (northern Central) Valley of California (CA) has a hot Mediterranean climate and a diverse ecological landscape that is impacted extensively by human activities, which include the intensive farming of crops and livestock. Waste-water ponds, marshes, and irrigated fields associated with these agricultural activities provide abundant larval habitats for C. sonorensis midges, in addition to those sites that exist in the natural environment. Within this region, C. sonorensis is an important vector of bluetongue (BTV) and related viruses that adversely affect the international trade and movement of livestock, the economics of livestock production, and animal welfare. To characterize the seasonal dynamics of immature and adult C. sonorensis populations, abundance was monitored intensively on two dairy farms in the Sacramento Valley from August 2012- to July 2013. Adults were sampled every two weeks for 52 weeks by trapping (CDC style traps without light and baited with dry-ice) along N-S and E-W transects on each farm. One farm had large operational waste-water lagoons, whereas the lagoon on the other farm was drained and remained dry during the study. Spring emergence and seasonal abundance of adult C. sonorensis on both farms coincided with rising vernal temperature. Paradoxically, the abundance of midges on the farm without a functioning waste-water lagoon was increased as compared to abundance on the farm with a waste-water lagoon system, indicating that this infrastructure may not serve as the sole, or even the primary larval habitat. Adult midges disappeared from both farms from late November until May; however, low numbers of parous female midges were detected in traps set during daylight in the inter-seasonal winter period. This latter finding is especially critical as it provides a potential mechanism for the "overwintering" of BTV in temperate regions such as northern CA. Precise documentation of temporal changes in the annual abundance and dispersal of Culicoides midges is essential for the creation of models to predict BTV infection of livestock and to develop sound abatement strategies

    Recruitment of Men Into a Pragmatic Rural Primary Care Weight Loss Trial

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    This article is distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 License which permits non-commercial use, reproduction and distribution of the work without further permission provided the original work is attributed as specified on the SAGE and Open Access pages (https://us.sagepub.com/en-us/nam/open-access-at-sage).Men remain underrepresented in behavioral weight loss trials and are more difficult to recruit compared to women. We describe recruitment response of men and women into a mixed-gender behavioral weight loss trial conducted within 36 rural primary care clinics. Participants were recruited through primary care clinics via direct mailings (n = 15,076) and in-clinic referrals by their primary care provider (PCP). Gender differences were examined in response rate to direct mailings, study referral source, and rates of proceeding to study screening, being eligible, and enrolling. Men had a lower response rate to direct mailings than women (7.8% vs. 17.7%, p < .001). Men (vs. women) responding to the mailing were more likely to respond by opt-in postcard (64.6% vs. 56.8%) and less likely to respond by phone (33.9% vs. 39.6%), p = .002. Among potential participants contacting the study (n = 2413), men were less likely to report being referred by PCPs (15.2% vs. 21.6%; p < .001), but were just as likely to proceed to screening, be eligible, and enroll. Men and women were more likely to proceed to screening when referred by PCPs (93.3% vs. 95.4%) compared to direct mailings (74.2% vs. 73.9%). Enrolled men were older (p < .001), more likely to be married (p = .04), and had higher levels of education (p = .01). Men were less likely than women to respond to direct mailings and to be referred by their PCP, but after contacting the study, had similar screening, eligibility, and enrollment rates. Encouraging and training providers to refer men during clinic visits may help recruit more men into primary care-based weight loss trials.Patient Centered Outcomes Research Institute (OTO-1402-09413

    Gonadal Histo-Morphology and Antifertility Effects of Bonny Light Crude Oil in Male Rats

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    The study investigated the antifertility effects of ingestion of Bonny Light Crude Oil (BLCO) at a dose of 0.5, 1.5 2.5 and 3.5ml/kg body weight in adult male rats following oral administration for 60days. The animals were sacrificed, the epididymal spermatozoa expressed out and a homogenate made for semen analysis. The testes were removed for histological processing. The sperm count was significantly reduced (21.80±0.57, 19.00±0.85, 16.20±0.00 and 12.90±0.99 million/ml respectively) when compared to their corresponding control groups 26.30±1.27, 25.50±0.71, 26.70±2.69, and 25.60±0.57 million/ml) at P?0.05. Degenerative and necrotic changes of cells in the seminiferous tubules and interstitium  was observed in the histology of the testes. BLCO has adverse effects on male reproductive system. This may imply possible antifertility for male rats exposed to BLCO ingestion. Keywords: Bonny light crude oil, testes, antifertility, male ra

    Transmission Based Precaution Practices among Nurses in Edo State, Nigeria during COVID-19 Pandemic

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    The novel covid-19 pandemic is a highly infectious disease without known specific treatment and vaccine. Transmission based precautions are important in the fight against the virus. This study investigated the level of transmission-based precautions practiced, the predictors of correct practices, and the challenges experienced by nurses in public health facilities in Edo State during the outbreak of the Covid-19 pandemic. The study employed a descriptive cross-sectional survey to elicit responses from 367 front line nurses using a Google online questionnaire. Data analysis involved descriptive statistics and logistic regression analysis. The majority 314(85.6%) of the respondents maintained a good level of transmission-based precautions practice. Hand hygiene was performed by 327(89.1%) of the respondents. Academic qualification was a significant predictor of good practice in favour of respondents with a degree in nursing. Challenges identified were lack of financial motivation, fear of infecting familymembers and fear of contracting the virus (93.5%). It was concluded that nurses in Edo State Nigeria have good transmissionbased practices in relation to covid-19 however efforts should be made to ensure 100% compliance and sustain practices. Keywords: Covid-19, Health facilities, Nurses, Practice, Transmission based precautions, Edo State, Nigeria La nouvelle pandémie de covid-19 est une maladie hautement infectieuse sans traitement ni vaccin spécifiques connus. Les précautions liées à la transmission sont importantes dans la lutte contre le virus. Cette étude a examiné le niveau de précautions fondées sur la transmission pratiquées, les prédicteurs de bonnes pratiques et les défis rencontrés par les infirmières dans les établissements de santé publique de l'État d'Edo pendant l'éclosion de la pandémie de Covid-19. L'étude a utilisé une enquête transversale descriptive pour obtenir des réponses de 367 infirmières de première ligne à l'aide d'un questionnaire en ligne de Google. L'analyse des données impliquait des statistiques descriptives et une analyse de régression logistique. La majorité 314 (85,6%) des répondants ont maintenu un bon niveau de pratique des précautions fondées sur la transmission. L'hygiène des mains a été pratiquée par 327 (89,1%) des répondants. La qualification académique était un prédicteur significatif des bonnes&nbsp; pratiques en faveur des répondants titulaires d'un diplôme en sciences infirmières. Les défis identifiés étaient le manque de motivation financière&nbsp; la peur d'infecter les membres de la famille et la peur de contracter le virus (93,5%). Il a été conclu que les i nfirmières de l'État d'Edo au Nigéria ont de bonnes pratiques fondées sur la transmission par rapport à la covid-19, mais des efforts devraient être faits pour assurer une conformité à 100% et maintenir les pratiques. Mots-clés: Covid-19, Health facilities, Nurses, Practice, Transmission based precautions, Edo State, Nigeria &nbsp
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