1,842 research outputs found
Exact 1-D Model for Coherent Synchrotron Radiation with Shielding and Bunch Compression
Coherent Synchrotron Radiation has been studied effectively using a
1-dimensional model for the charge distribution in the realm of small angle
approximations and high energies. Here we use Jefimenko's form of Maxwell's
equations, without such approximations, to calculate the exact wake-fields due
to this effect in multiple bends and drifts. It has been shown before that the
influence of a drift can propagate well into a subsequent bend. We show, for
reasonable parameters, that the influence of a previous bend can also propagate
well into a subsequent bend, and that this is especially important at the
beginning of a bend. Shielding by conducting parallel plates is simulated using
the image charge method. We extend the formalism to situations with compressing
and decompressing distributions, and conclude that simpler approximations to
bunch compression usually overestimates the effect. Additionally, an exact
formula for the coherent power radiated by a Gaussian bunch is derived by
considering the coherent synchrotron radiation spectrum, and is used to check
the accuracy of wake-field calculations
The role of informatics in prehospital emergency resuscitation and defibrillation
Out-of-hospital cardiac arrests account for a large number of deaths as the time window for successful resuscitation is very short. Timely call for help, resuscitation and defibrillation by laypersons are crucial for the survival and outcome of cardiac arrest victims. Good quality data and informatics play an important role in the effectiveness of the chain of survival. Information about defibrillator location is vital for emergency services to direct bystanders; informatics also helps to strategically place defibrillators for optimal use. Technologies, such as location-based systems are being used to keep track of defibrillators and also alert volunteer responders to emergencies. Informatics also plays a role in post resuscitation care and research by facilitating the linkage and interoperability of health data between different systems, such as ambulance service, hospital, and other health data such as cardiac arrest registries
Perspectives of UK community first responders on a national public access defibrillator database
Background: Out-of-hospital cardiac arrest (OHCA) survival to hospital discharge in the United Kingdom is lower than in many other developed regions, with England 9% [1] and Scotland 5% [2], compared to North Holland Province, the Netherlands 21% [3] and Norway 25% [4]. In 2015, the British Heart Foundation commissioned a feasibility study into the establishment of a national Public Accessible Defibrillator (PAD) database for the UK and how it could improve OHCA survival. As part of this feasibility study, the views of a range of stakeholders were sought, including those of community first responders (CFRs). CFRs are volunteers from local communities who attend to emergency calls received by the ambulance service and provide care until an ambulance arrives. There were over 12,000 CFRs operating across the UK in 2014 [5]. Most of the PADs are static AEDs made available in public places. The alternative is the use of mobile defibrillators that are carried to the scene of an emergency by CFRs [6].
Methods: A survey was designed with 12 questions. It covered the areas of CFR demographics, experience with PADs, and their views on a national PAD database and the technologies and apps available for locating defibrillators and for alerting lay responders of an emergency. The survey questionnaire was made available via an online survey tool (SurveyMonkey). Between November and December 2015, links to the survey were sent via email to CFRs via the National Ambulance Services Responder Managers Forum [7].
Results: 760 responses were received (6.3% response rate) with 12 out 14 ambulance service regions represented. The experience of CFRs ranges from none (just finished training) to 16 years, with the largest proportion having under 2 years experience (47.28%, 322 of 681). Awareness of apps and their use was variable with a reasonable knowledge of GoodSAM, AED Locator and the South Central Ambulance Service app but 75% did not know if apps are routinely used in their area. 35.47% of respondents (255 of 719) felt a national database of AED locations would have a significant impact on awareness and use of defibrillators with a further 42.84% (308 of 719) thinking it would have some impact. Additionally, the use of apps linked to a national database was supported by over 85% of respondents.
Conclusion:
In the survey, CFRs expressed generally positive opinions about a national PAD database and linked apps. The need for it arises naturally from having defibrillators in the community and is an additional tool to help save lives. Issues that need to be considered however include information accuracy and maintenance; the need for training combined with first aid and CPR. CFRs identified the main barriers to defibrillator use as (1) not knowing how to use one, (2) not knowing where to find one and (3) fear of injury to the victim. Lack of awareness amongst the public about the availability and use of defibrillators was highlighted as a major challenge and the absolute need for a high profile and awareness raising campaign was flagged
Positive Surgical Margins in the 10 Most Common Solid Cancers.
A positive surgical margin (PSM) following cancer resection oftentimes necessitates adjuvant treatments and carries significant financial and prognostic implications. We sought to compare PSM rates for the ten most common solid cancers in the United States, and to assess trends over time. Over 10 million patients were identified in the National Cancer Data Base from 1998-2012, and 6.5 million had surgical margin data. PSM rates were compared between two time periods, 1998-2002 and 2008-2012. PSM was positively correlated with tumor category and grade. Ovarian and prostate cancers had the highest PSM prevalence in women and men, respectively. The highest PSM rates for cancers affecting both genders were seen for oral cavity tumors. PSM rates for breast cancer and lung and bronchus cancer in both men and women declined over the study period. PSM increases were seen for bladder, colon and rectum, and kidney and renal pelvis cancers. This large-scale analysis appraises the magnitude of PSM in the United States in order to focus future efforts on improving oncologic surgical care with the goal of optimizing value and improving patient outcomes
Community-Informed Relationship Violence Intervention in a HighStress, Low-Income Urban Context
To evaluate the effectiveness of the House of Ruth Marylandâs Gateway Project, a community-informed and oppression-sensitive relationship violence intervention program (RVIP; commonly labeled âbatterer interventionâ), designed for a predominantly low-income, racial minority population residing in a high-stress urban context. Method: Propensity score matching with data on 744 male program participants (89% Black; 59% unemployed; 76% on probation) was used to compare recidivism rates for those who did, and did not, complete the intervention program. The propensity score matching created comparison groups (n = 216 per group) with very similar distributions on 28 balancing factors. Results: During the year after program enrollment, program completers had significantly lower frequency of re-arrest for all criminal offenses, d = 0.16, p = .018 and marginally lower frequency of violent offenses, d = 0.12, p = .075 than matched non-completers. No treatment effect was identified for partner-abuse-related legal involvements, d = 0.06, p = .365. Secondary analyses controlling for propensity score in the full sample yielded similar results, and analyses of session attendance as a continuous variable found additional evidence of a significant program effect on violent offenses in the matched sample. Conclusions: In contrast to a carefully matched sample of program non-completers, men who completed this 28-session intervention, which adapts the traditional RVIP focus on power and control to address the life context of participants who experience systemic oppression, discrimination, economic distress, and community violence, had lower overall involvement with the criminal justice system
The complete mitogenome of an undescribed clam shrimp of the genus Gondwanalimnadia (Branchiopoda: Spinicaudata), from a temporary wetland in Central District, Botswana
Clam shrimps (Spinicaudata) are a widespread and diverse crustacean group that frequent temporary aquatic habitats, but few complete mitochondrial genomes have been published for this group. Here, we report the mitogenome of an undescribed Gondwanalimnadia species from Botswana. Raw sequences were assembled into a single circular genome with a total length of 15,663âbp. Thirteen protein-coding genes, 22 tRNAs, and 2 rRNAs were identified using the MITOS pipeline. The mitogenomeâs GC content is 33.52%. Phylogenetic analysis using protein-coding genes confirmed that Gondwanalimnadia sp. is closely related to another member of the Limnadiidae, Limnadia lenticularis
The pesticide adjuvant, Toximulâą, alters hepatic metabolism through effects on downstream targets of PPARα
AbstractPrevious studies demonstrated that chronic dermal exposure to the pesticide adjuvant (surfactant), Toximul⹠(Tox), has significant detrimental effects on hepatic lipid metabolism. This study demonstrated that young mice dermally exposed to Tox for 12 days have significant increases in expression of peroxisomal acyl-CoA oxidase (mRNA and protein), bifunctional enzyme (mRNA) and thiolase (mRNA), as well as the P450 oxidizing enzymes Cyp4A10 and Cyp4A14 (mRNA and protein). Tox produced a similar pattern of increases in wild type adult female mice but did not induce these responses in PPARα-null mice. These data support the hypothesis that Tox, a heterogeneous blend of nonionic and anionic surfactants, modulates hepatic metabolism at least in part through activation of PPARα. Notably, all three groups of Tox-treated mice had increased relative liver weights due to significant accumulation of lipid. This could be endogenous in nature and/or a component(s) of Tox or a metabolite thereof. The ability of Tox and other hydrocarbon pollutants to induce fatty liver despite being PPARα agonists indicates a novel consequence of exposure to this class of chemicals, and may provide a new understanding of fatty liver in populations with industrial exposure
Life saving apps : linking cardiac arrest victims to emergency services and volunteer responders
In cases of emergency, such as out-of-hospital cardiac arrests, the first few minutes are crucial for victims to receive care and have a positive outcome. However, emergency services often arrive on scene after those first few minutes, making any bridging solutions key. Finding a defibrillator or accessing a trained volunteer responder are some of the technologicalsolutions that are being developed to support the chain of survival. This paper looks at technologies, in particular those linked to mobile apps that have been used to locate defibrillators and responder apps that enable responders to attend to nearby emergencies. We review a selection of apps and also assess the challenges and considerations for such apps
The complete mitogenome of the fairy shrimp Streptocephalus cafer (Lovén, 1847) (Crustacea: Branchiopoda: Anostraca) from an ephemeral pond in Botswana, southern Africa
Fairy shrimps (Anostraca) constitute an important component of seasonally aquatic habitats, but few complete mitochondrial genomes have been published for this group. Here, we report the mitogenome of a common southern African species, Streptocephalus cafer, from Botswana (accession number: MN720104). Low-coverage shotgun sequencing recovered two contigs 15653âbp and 1347âbp in length that are separated by a repetitive region of unknown length within the non-coding control region. The mitogenomeâs GC content is 31.80%. Phylogenetic analysis using protein-coding genes confirms the sister taxon relationship of S. cafer with the only other congener whose mitogenome has been reconstructed to date, the Asian S. sirindhornae
One-arcsecond line-of-sight pointing control on exoplanetsat, a three-unit CubeSat
ExoplanetSat is a proposed 10Ă10Ă34-cm space telescope designed to detect down to Earth-sized exoplanets in an orbit out to the habitable zone of bright, Sun-like stars via the transit method. Achieving this science objective requires one-arcsecond line-of-sight pointing control for the science CCD detector, an unprecedented requirement for CubeSats. A two-stage control architecture that coordinates coarse rigid-body attitude control with fine line-of-sight pointing control will be employed to meet this challenging pointing requirement. Detailed testing of the reaction wheels and CMOS detectors has been performed to extract key performance parameters used in simulations. The results of these simulations indicate that a 1.4 arcsecond pointing precision (3Ï) is achievable. To meet the 1.0-arcsecond pointing requirement, several options are analyzed. In particular, a new technique to estimate reaction wheel vibrations for feed forward cancellation of reaction wheel vibrations is presented. This estimator adaptively estimates disturbances from noisy sensor measurements and effectively stores disturbance amplitude and phase in memory as a function of wheel speed. In addition to these simulation results, testing results from a hardware-in-the-loop (HWIL) testbed demonstrate the capability of the fine pointing control loop. Future plans for complete HWIL testing of the coarse and fine control loops are presented
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