374 research outputs found

    Middle Paleolithic Hominin Lake Environments in Saharan North Africa

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    Contemporaneous with the transition to biologically modern humans was the episodic change from wetter to drier environments in the Egyptian Sahara. At Bir Tarfawi, White Lake sediments represent a wet phase occurring prior to the last interglacial in the now hyperarid Egyptian Western Desert. One hypothesis for the development of Western Desert Pleistocene lakes was that the northward migration of the Intertropical Convergence Zone (ITCZ) provided a path for summer-constrained, Atlantic-sourced precipitation resulting in local precipitation. Oxygen and carbon stable isotope analysis of climate proxies such as the gastropod, Melanoides tuberculata, indicate precipitation and groundwater sources as well as the ephemeral or perennial character of the surface water. Unaltered diagenetically, Melanoides from a coquina in White Lake sediments had shell carbonate oxygen isotope values from -7.7‰ to 0.8‰. Along shell oxygen isotope values varied from 3‰ to 6‰ with no indication of highly depleted values indicative of Atlantic-sourced monsoon. Also, the shell oxygen isotope values were higher than previously published perennial lake sediment carbonates (-8.3‰ to -5.7‰). The enriched oxygen isotope values for White Lake remnant Melanoides suggest the coquina may have formed in shallow waters sensitive to evaporation and multiple precipitation sources, e.g. Indian Ocean, contradicting the hypothesis that the Atlantic monsoon was the sole contributor to the perennial White Lake

    Diagenesis in salt dome roof strata: barite - calcite assemblage in Jebel Madar, Oman

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    Halokinesis causes a dynamic structural evolution with the development of faults and fractures, which can act as either preferential fluid pathways or barriers. Reconstructing reactive fluid flow in salt dome settings remains a challenge. This contribution presents for the first time a spatial distribution map of diagenetic phases in a salt dome in northern Oman. Our study establishes a clear link between structural evolution and fluid flow leading to the formation of diagenetic products (barite and calcite) in the salt dome roof strata. Extensive formation of diagenetic products occurs along NNE-SSW to NE-SW faults and fractures, which initiated during the Santonian (Late Cretaceous) and were reactivated in the Miocene, but not along the E-W fault, which was generated during Early Paleocene time. We propose that the diagenetic products formed by mixing of a warm (100 °C) saline (17 wt% NaCl eq.) 87Sr enriched (87Sr/86Sr: 0.71023) fluid with colder (35 °C) meteoric fluid during Miocene to Pleistocene. The stable sulphur and strontium isotope composition and fluid inclusion data indicate that a saline fluid, with sulfate source derived from the Ara Group evaporite and Haima Supergroup layers, is the source for barite formation at about 100 °C, predominantly at fault conjunctions and minor faults away from the main graben structure in the dome. In the Miocene, the saline fluid probably ascended along a halokinesis-related fault due to fluid overpressure (due to the rising salt and impermeable layers in the overlying stratigraphic sequence), and triggered the formation of barite due mixing with barium-rich fluids, accompanied by a drop in temperature. Subsequently, evolving salt doming with associated fault activity and erosion of the Jebel allows progressively more input of colder meteoric fluids, which mix with the saline warmer fluid, as derived from stable isotope data measured in the progressively younger barite-associated calcite, fault zone calcite and macro-columnar calcite. The reconstructed mixing model indicates a 50/50 to 90/10 meteoric/saline fluid mixing ratio for the formation of fault zone calcite, and a 10 times higher concentration of carbon in the saline fluid end member compared to the meteoric fluid end member. The presented mixing model of salt-derived fluids with meteoric fluids is suggested to be a general model applicable to structural diagenetic evolution of salt domes world wide

    Post-exercise management of exertional hyperthermia in dogs participating in dog sport (canicross) events in the UK

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    Exercise is a common trigger of heat-related illness (HRI) events in dogs, accounting for 74% of canine HRI cases treated under primary veterinary care in the United Kingdom. However, few empirical studies have evaluated the effectiveness of differing cooling methods for dogs with exertional hyperthermia or HRI. This study aimed to prospectively evaluate effects of ambient conditions and post-exercise management practices (cooling methods and vehicular confinement) on the post-exercise temperature change of dogs participating in UK canicross events. Canine temperature was recorded at three intervals post-exercise: as close as possible to 0- (immediately post-exercise), 5-, and 15-min post-exercise. Ambient conditions and post-exercise management were recorded for 115 cooling profiles from 52 dogs. In 28/115 (24.4%) profiles, the dog's temperature increased during the first 5-min post-exercise. Overall, 68/115 (59.1%) profiles included passive cooling (stood or walked outside), 35 (30.4%) active cooling (cold-water immersion or application of a cooling coat), and 12 (10.4%) involved no cooling and were immediately housed in vehicles. No dogs developed hypothermia during the study and no adverse effects were observed from any cooling method. In hyperthermic dogs, overall post-exercise body temperature change was significantly negatively associated (i.e. the dogs cooled more) with 0-min post-exercise body temperature (β = −0.93, p &lt; 0.001), and not being housed in a vehicle (β = −0.43, p = 0.013). This study provides evidence cold-water immersion (in water at 0.1–15.0 °C) can be used to effectively and safely cool dogs with exertional hyperthermia. Progressive temperature increases in many dogs - even after exercise has terminated - supports the message to “cool first, transport second” when managing dogs with HRI. When transporting dogs post-exercise or with HRI even after active cooling, care should be taken to cool the vehicle before entry and promote air movement around the dog during transport to facilitate ongoing cooling and prevent worsening of hyperthermia during travel.</p

    A mixed methods approach to developing and evaluating oncology trainee education around minimization of adverse events and improved patient quality and safety

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    BACKGROUND: Adverse events are a significant quality and safety issue in the hospital setting due to their direct impact on patients. Additionally, such events are often handled by junior doctors due to their direct involvement with patients. As such, it is important for health care organizations to prioritize education and training for junior doctors on identifying adverse events and handling them when they occur. The Cancer Cup Challenge is an educational program focuses on quality improvement and adverse event awareness targeting for junior oncology doctors across three international sites. METHODS: A mixed methodology was used to develop and evaluate the program. The Qstream spaced learning platform was used to disseminate information to participants, as it has been demonstrated to impact on both knowledge and behavior. Eight short case based scenarios with expert feedback were developed by a multidisciplinary advisory committee containing representatives from the international sites. At the conclusion of the course impact on participant knowledge was evaluated using analysis of the metrics collected by the Qstream platform. Additionally, an online survey and semi-structured interviews were used to evaluate engagement and perceived value by participants. RESULTS: A total of 35 junior doctors registered to undertake the Qstream program, with 31 (88.57 %) successfully completing it. Analysis of the Qstream metrics revealed 76.57 % of cases were answered correctly on first attempt. The post-program survey received 17 responses, with 76.47 % indicating cases for the course were interesting and 82.35 % feeling cases were relevant. Finally, 14 participants consented to participate in semi-structured interviews about the program, with feedback towards the course being generally very positive. CONCLUSIONS: Our study demonstrates that an online game is well accepted by junior doctors as a method to increase their quality improvement awareness. Developing effective and sustainable training for doctors is important to ensure positive patient outcomes are maintained in the hospital setting. This is particularly important for junior doctors as they are working closely with patients and learning skills and behaviors, which will influence their practice throughout their careers

    Priorities and strategies for improving disabled women's access to maternity services when they are affected by domestic abuse:a multi-method study using concept maps

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    BACKGROUND: Domestic abuse is a significant public health issue. It occurs more frequently among disabled women than those without a disability and evidence suggests that a great deal of domestic abuse begins or worsens during pregnancy. All women and their infants are entitled to equal access to high quality maternity care. However, research has shown that disabled women who experience domestic abuse face numerous barriers to accessing care. The aim of the study was to identify the priority areas for improving access to maternity services for this group of women; develop strategies for improved access and utilisation; and explore the feasibility of implementing the identified strategies. METHODS: This multi-method study was the third and final part of a larger study conducted in the UK between 2012 and 2014. The study used a modified concept mapping approach and was theoretically underpinned by Andersen’s model of healthcare use. Seven focus group interviews were conducted with a range of maternity care professionals (n = 45), incorporating quantitative and qualitative components. Participants ranked perceived barriers to women’s access and utilisation of maternity services in order of priority using a 5-point Likert scale. Quantitative data exploration used descriptive and non-parametric analyses. In the qualitative component of each focus group, participants discussed the barriers and identified potential improvement strategies (and feasibility of implementing these). Qualitative data were analysed inductively using a framework analysis approach. RESULTS: The three most highly ranked barriers to women’s access and utilisation of maternity services identified in the quantitative component were: 1) staff being unaware and not asking about domestic abuse and disability; 2) the impact of domestic abuse on women; 3) women’s fear of disclosure. The top two priority strategies were: providing information about domestic abuse to all women and promoting non-judgemental staff attitude. These were also considered very feasible. The qualitative analysis identified a range of psychosocial and environmental barriers experienced by this group of women in accessing maternity care. Congruent with the quantitative results, the main themes were lack of awareness and fear of disclosure. Key strategies were identified as demystifying disclosure and creating physical spaces to facilitate disclosure. CONCLUSIONS: The study supports findings of previous research regarding the barriers that women face in accessing and utilising maternity services, particularly regarding the issue of disclosure. But the study provides new evidence on the perceived importance and feasibility of strategies to address such barriers. This is an important step in ensuring practice-based acceptability and ease with which improvement strategies might be implemented in maternity care settings

    Access and utilisation of maternity care for disabled women who experience domestic abuse:a systematic review

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    BACKGROUND: Although disabled women are significantly more likely to experience domestic abuse during pregnancy than non-disabled women, very little is known about how maternity care access and utilisation is affected by the co-existence of disability and domestic abuse. This systematic review of the literature explored how domestic abuse impacts upon disabled women’s access to maternity services. METHODS: Eleven articles were identified through a search of six electronic databases and data were analysed to identify: the factors that facilitate or compromise access to care; the consequences of inadequate care for pregnant women’s health and wellbeing; and the effectiveness of existing strategies for improvement. RESULTS: Findings indicate that a mental health diagnosis, poor relationships with health professionals and environmental barriers can compromise women’s utilisation of maternity services. Domestic abuse can both compromise, and catalyse, access to services and social support is a positive factor when accessing care. Delayed and inadequate care has adverse effects on women’s physical and psychological health, however further research is required to fully explore the nature and extent of these consequences. Only one study identified strategies currently being used to improve access to services for disabled women experiencing abuse. CONCLUSIONS: Based upon the barriers and facilitators identified within the review, we suggest that future strategies for improvement should focus on: understanding women’s reasons for accessing care; fostering positive relationships; being women-centred; promoting environmental accessibility; and improving the strength of the evidence base
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