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NDL: A Domain-Specific Language for Device Drivers
Device drivers are difficult to write and error-prone. They are usually written in C, a fairly low-level language with minimal type safety and little support for device semantics. As a result, they have become a major source of instability in operating system code. This paper presents NDL, a language for device drivers. NDL provides high-level abstractions of device resources and constructs tailored to describing common device driver operations. We show that NDL allows for the coding of a semantically correct driver with a code size reduction of more than 50% and a minimal impact on performance
Carbon sequestration on Mars
On Earth, carbon sequestration in geologic units plays an important role in the carbon cycle, scrubbing CO_2 from the atmosphere for long-term storage. While carbonate is identified in low abundances within the dust and soils of Mars, at <1 wt% in select meteorites, and in limited outcrops, no massive carbonate rock reservoir on Mars has been identified to date. Here, we investigate the largest exposed carbonate-bearing rock unit, the Nili Fossae plains, combining spectral, thermophysical, and morphological analyses to evaluate the timing and carbon sequestration potential of rocks on Mars. We find that the olivine-enriched (∼20%–25%) basalts have been altered, by low-temperature in situ carbonation processes, to at most ∼20% Fe-Mg carbonate, thus limiting carbon sequestration in the Nili Fossae region to ∼0.25–12 mbar of CO_2 during the late Noachian–early Hesperian, before or concurrent with valley network formation. While this is large compared to modern-day CO_2 reservoirs, the lack of additional, comparably sized post–late Noachian carbonate-bearing deposits on Mars indicates ineffective carbon sequestration in rock units over the past ∼3.7 b.y. This implies a thin atmosphere (≲500 mbar) during valley network formation, extensive post-Noachian atmospheric loss to space, or diffuse, deep sequestration by a yet-to-be understood process. In stark contrast to Earth’s biologically mediated crust:atmosphere carbon reservoir ratio of ∼10^4–10^5, Mars’ ratio is a mere ∼10–10^3, even if buried pre-Noachian crust holds multiple bars
Charity and Prosperity: The Economic Impact of Public Charities in Arkansas 2006-2010
In 2010, public charities in Arkansas had a total economic impact of 25,000 in total revenue per year. Data for calendar years 2006 through 2010 are analyzed for this study; data for 2011 and 2012 are not yet available.In examining only those organizations with more than 25,000 (these organizations are not required to file annual reports to the IRS). These data include information only for public charities, which are guided by 501(c)(3) rules. In doing so, this report excludes information about private foundations, churches, social and fraternal organizations, or other groups considered tax-exempt under other sections of the tax code. Consequently, results presented in this report actually understate the true effects of the nonprofit sector for Arkansas. Therefore, when discussing results about nonprofits in Arkansas, this research is addressing the effect of service provided by public charities onl
Relationships of Clinical, Psychologic, and Individual Factors with the Functional Status of Neck Pain Patients
AbstractObjectiveThe objective of this study was to use both generic and disease-specific functional measures examining relationships of clinical, psychologic, and individual factors with the functional status of neck pain patients.MethodsPatients who visited a university-based spine clinic and reported neck pain were included in this study. A comprehensive computerized survey questionnaire was used to collect the information related to this study. The questionnaire also contained a generic measure, short form 12-item survey (SF-12), and a disease-specific measure, neck disability index (NDI). Correlation and multiple regression analysis were conducted to examine the relationships.ResultsA range of clinical, psychologic, and individual factors emerged to be significant predictors of the NDI or physical component of the SF-12 (PCS). The predictors of higher NDI included higher levels of neck pain, higher levels of back pain, higher levels of pain in arm or shoulder areas, not working, lower education, higher stress, the presence of depression or anxiety, and smoking. The predictors of lower PCS included not working, higher levels of back pain, higher levels of neck pain, lower education, female sex, the presence of cardiovascular disorders, the absence of cervical disk disorders, and older age.Conclusions The  predictors  of  the  NDI  or  PCS  appear to be multidimensional. Interventions designed to maximally improve the functional status of neck pain patients should be multifaceted and involve multidisciplinary teams. Selection of the most appropriate functional measures for an intervention study should consider differences between the generic and disease-specific measures in terms of their respective relationships with targeted factors. Prospective studies are needed to confirm the relationships observed in this study
Do In-Vehicle Advance Signs Benefit Older and Younger Driver Intersection Performance?
An experimental study was conducted to determine if intersection behavior of those 18 to 24 and 65+ benefited from advanced in-vehicle signs presented in a head-up display (HUD) format. The University of Calgary Driving Simulator (UCDS) was used to determine whether intersection performance improved in the presence of several advanced signs or whether unwanted adaptive behaviors occurred (e.g., increasing speed to run the light instead of stopping). Invehicle signs facilitated an increase in stopping occurrences for both younger and older drivers at intersections with relatively short yellow onsets. In addition, eye movement analysis revealed significant age effects with regard to vertical and horizontal gaze variablity, with younger drivers showing increases in vertical gaze variability compared to the older drivers. Younger drivers also looked more often and had longer percentage of durations fixating on the HUD compared to the older drivers
Corticospinal and intracortical responses from both motor cortices following unilateral concentric versus eccentric contractions
Cross-education is the phenomenon where training of one limb can cause neuromuscular adaptations in the opposite untrained limb. This effect has been reported to be greater after eccentric (ECC) than concentric (CON) strength training; however, the underpinning neurophysiological mechanisms remain unclear. Thus, we compared responses to transcranial magnetic stimulation (TMS) in both motor cortices following single sessions of unilateral ECC and CON exercise of the elbow flexors. Fourteen healthy adults performed three sets of 10 ECC and CON right elbow flexor contractions at 75 % of respective maximum on separate days. Elbow flexor maximal voluntary isometric contraction (MVIC) torques were measured before and after exercise, and responses to single- and paired-pulse TMS were recorded from the non-exercised left and exercised right biceps brachii. Pre-exercise and post-exercise responses for ECC and CON were compared by repeated measures analyses of variance (ANOVAs). MVIC torque of the exercised arm decreased (p \u3c 0.01) after CON ( − 30 ± 14 %) and ECC ( − 39 ± 13 %) similarly. For the non-exercised left biceps brachii, resting motor threshold (RMT) decreased after CON only ( − 4.2 ± 3.9 % of maximum stimulator output [MSO], p \u3c 0.01), and intracortical facilitation (ICF) decreased (−15.2 ± 20.0 %, p = 0.038) after ECC only. For the exercised right biceps, RMT increased after ECC (8.6 ± 6.2 % MSO, p = 0.014) but not after CON (6.4 ± 8.1% MSO, p = 0.066). Thus, unilateral ECC and CON elbow flexor exercise modulated excitability differently for the non-exercised hemisphere. These findings suggest that responses after a single bout of exercise may not reflect longer term adaptations
New records of biting midges of the genus \u3ci\u3eCulicoides\u3c/i\u3e Latreille from the southeastern United States (Diptera: Ceratopogonidae)
We provide new state and county records of biting midges in the genus Culicoides Latreille (Diptera: Ceratopogonidae) from the southeastern United States collected with CDC miniature light traps during 2007–2012 in Florida, Georgia, Alabama, Mississippi, Louisiana, Arkansas, and Texas. The primary goals of the surveys were to identify the presence of exotic Culicoides, and determine the ranges of known and possible vectors of bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV). Included are the first records of: Culicoides (Amossovia) beckae Wirth and Blanton from Louisiana and Mississippi, C. (A.) oklahomensis Khalaf from Alabama and Arkansas, C. (Avaritia) alachua Jamnback and Wirth from Alabama, C. (Culicoides) neopulicaris Wirth from Alabama, C. (Drymodesmyia) butleri Wirth and Hubert from Texas, C. (Hoffmania) insignis Lutz from Mississippi, C. (Oecacta) barbosai Wirth and Blanton from Georgia, C. (Silvaticulicoides) loisae Jamnback from Alabama, and C. kirbyi Glick and Mullen from Mississippi. We also provide new Florida county records for C. alachua, C. barbosai, C. (Beltranmyia) hollensis (Melander and Brues), C. insignis, and C. (Monoculicoides) sonorensis Wirth and Jones; a new Georgia county record for C. alachua; and new Alabama county records for C. insignis, and C. sonorensis
Structural and magnetic properties of GdCo5−xNix
GdCo5 may be considered as two sublattices—one of Gd and one of Co—whose magnetizations are in antiparallel alignment, forming a ferrimagnet. Substitution of nickel in the cobalt sublattice of GdCo5 has been investigated to gain insight into how the magnetic properties of this prototype rare earth/transition-metal magnet are affected by changes in the transition-metal sublattice. Polycrystalline samples of GdCo5-xNix for 0 ≤ x ≤ 5 were synthesized by arc melting. Structural characterization was carried out by powder x-ray diffraction and optical and scanning electron microscope imagings of metallographic slides, the latter revealing a low concentration of Gd2(Co,Ni)7 lamellae for x ≤ 2.5. Compensation—i.e., the cancellation of the opposing Gd and transition-metal moments—is observed for 1< x < 3 at a temperature which increases with Ni content; for larger x , no compensation is observed below 360 K. A peak in the coercivity is seen at x ≈ 1 at 10 K coinciding with a minimum in the saturation magnetization. Density-functional theory calculations within the disordered local moment picture reproduce the dependence of the magnetization on Ni content and temperature. The calculations also show a peak in the magnetocrystalline anisotropy at similar Ni concentrations to the experimentally observed coercivity maximum
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