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81.
Geological and seasonal weather variations govern the geohydrological properties of the Avonlea badlands in Saskatchewan, Canada. Three surface sediments exhibiting distinct lithologic variations were found: a steeply sloped and fissured sandstone; a mildly sloped and popcorn-textured mudrock; and a flat and eroded pediment. The fines content increased from the dry to the wet state, with contents of 17–33 % seen for sandstone, 4–98 % for mudrock, and 21–42 % for pediment. The water adsorption capacity was found to be highest for mudrock (w l = 96 % and w p = 47 %), followed by sandstone (w l = 39 % and w p = 31 %), and then by pediment (w l = 31 % and w p = 23 %). The soil water characteristic curves of sandstone and mudrock showed bimodal distributions with a low air entry value (6 and 9 kPa) pertaining to drainage through cracks and a high air entry value (160 and 92 kPa) associated with flow through the soil matrix. The pediment presented a unimodal soil water characteristic curve with a single matrix air entry value of 4 kPa. The saturated hydraulic conductivities for sandstone, mudrock, and pediment were measured as 8.5 × 10?6, 4.0 × 10?8, and 1.8 × 10?5 m/s, respectively.  相似文献   
82.
Biodegradable substrates and encapsulating materials play critical roles in the development of an emerging class of semiconductor technology, generally referred as “transient electronics”, whose key characteristic is an ability to dissolve completely, in a controlled manner, upon immersion in ground water or biofluids. The results presented here introduce the use of thin foils of Mo, Fe, W, or Zn as biodegradable substrates and silicate spin‐on‐glass (SOG) materials as insulating and encapsulating layers, with demonstrations of transient active (diode and transistor) and passive (capacitor and inductor) electronic components. Complete measurements of electrical characteristics demonstrate that the device performance can reach levels comparable to those possible with conventional, nontransient materials. Dissolution kinetics of the foils and cytotoxicity tests of the SOG yield information relevant to use in transient electronics for temporary biomedical implants, resorbable environmental monitors, and reduced waste consumer electronics.  相似文献   
83.
The corrosion inhibition of Al-Alloy (Al2024) in 0.5 M nitric acid solution at 30 °C was achieved using 4-4-dimethyloxazolidine-2-thione (DMT) as a corrosion inhibitor. The electrochemical performance of the DMT was studied by electrochemical impedance spectroscopy (EIS), potentiodynamic polarization measurements, and scanning electron microscopic study (SEM). The results indicated that DMT acts as an inhibitor for Al2024 in 0.5 M nitric acid. Polarization curves indicated that DMT was a mixed-type inhibitor. Inhibition efficiencies were observed to be increased with an increase in DMT concentration and attains approximately to 93.4% at 2 mM of DMT in 0.5 M nitric acid. The adsorption of DMT model on Al2024 surface obeyed in accordance with Langmuir adsorption isotherm model. The value of the free energy of adsorption ΔG ads indicated that the adsorption of DMT molecule was a spontaneous process and was typical of physical and chemical adsorption.  相似文献   
84.
Smartphone sensing and persuasive feedback design is enabling a new generation of wellbeing apps capable of automatically monitoring multiple aspects of physical and mental health. In this article, we present BeWell+ the next generation of the BeWell smartphone wellbeing app, which monitors user behavior along three health dimensions, namely sleep, physical activity, and social interaction. BeWell promotes improved behavioral patterns via feedback rendered as an ambient display on the smartphone’s wallpaper. With BeWell+, we introduce new mechanisms to address key limitations of the original BeWell app; specifically, (1) community adaptive wellbeing feedback, which generalizes to diverse user communities (e.g., elderly, children) by promoting better behavior yet remains realistic to the user’s lifestyle; and, (2) wellbeing adaptive energy allocation, which prioritizes monitoring fidelity and feedback responsiveness on specific health dimensions (e.g., sleep) where the user needs additional help. We evaluate BeWell+ with a 27 person, 19 day field trial. Our findings show that not only can BeWell+ operate successfully on consumer smartphones; but also users understand feedback and respond by taking steps towards leading healthier lifestyles.  相似文献   
85.
A surveillance study was carried out to determine the prevalence of Campylobacter in meat, milk and other food commodities in Pakistan. Over a period of 3 years (January 2002-December 2004), a total of 1636 food samples of meat, milk and other food commodities were procured from three big cities of Pakistan (Faisalabad, Lahore and Islamabad) and were analysed. Among meat samples, the highest prevalence (48%) of Campylobacter was recorded in raw chicken meat followed by raw beef (10.9%) and raw mutton (5.1%). Among other food commodities, the highest prevalence was observed in vegetable/fruit salad (40.9%), sandwiches (32%), cheese (11%) and raw bulk milk samples (10.2%). The overall prevalence of Campylobacter was found to be 21.5%, out of which 70.6% were identified as Campylobacter (C.) jejuni and 29.4% as C. coli. The study reported that the prevalence of Campylobacter spp. was significantly higher in the food commodities, which included raw/undercooked ingredients.  相似文献   
86.
The yield of upper gastrointestinal endoscopy (esophago-gastroduodenoscopy; EGD) in human immunodeficiency virus (HIV)-infected patients based on presenting symptoms has not been well studied. We studied consecutive patients with documented HIV infection undergoing EGD at a large innercity hospital between August 1, 1990 and December 31, 1993; all had presenting symptoms and indications for EGD prospectively recorded at the time of EGD. All endoscopic abnormalities were routinely subjected to biopsy, and extensive histopathological evaluation was performed. EGD was considered helpful when the findings stimulated specific therapeutic intervention other than antifungal or antacid medications. The specific indications for EGD in 156 patients were as follows: esophageal symptoms, 102 patients (65%); abdominal pain, 18 (12%); upper gastrointestinal bleeding, 25 (16%); refractory nausea and vomiting, 11 (7%). Overall, pathologic findings were identified in 116 patients (74%): in refractory esophageal symptoms, 82%; upper gastrointestinal bleeding, 92%; abdominal pain, 39%; nausea and vomiting, 27%. EGD with biopsy identified a specifically treatable opportunistic disorder other than Candida in 80 patients (51%), including idiopathic esophageal ulcer (22%) or viral esophagitis and/or duodenitis (29%). EGD was not helpful in 22.3% of cases, those involving Candida (12.3%) and peptic ulcer disease (PUD)-related causes (10%). The mean CD4 count of patients with opportunistic pathologic findings (24/mm3, n = 79) was significantly lower than that of patients with PUD/gastroesophageal reflux disease (GERD) (167/mm3, n = 9) or negative EGDs (165/mm3, n = 35). Overall, the results of EGD influenced patient management in 78% of cases. We conclude that selective symptom-specific use of EGD, particularly in patients with esophageal symptoms refractory to antifungal therapy or gastrointestinal bleeding, usually identifies specifically treatable abnormalities, whereas EGD is less useful for the evaluation of abdominal pain or nausea and vomiting.  相似文献   
87.
This study reports on a detailed clinical, electrophysiological, muscle computed tomography (CT) and laboratory investigation carried out on five families with definite linkage to chromosome 2p. Some clinical and laboratory features were common to most of the patients, such as the very high serum creatine kinase (CK) levels (mean 43.70 times the normal). The onset was most frequently in the late teens or early twenties with weakness and wasting of the pelvic girdle muscles. All patients had normal motor milestones and had not complained of any symptoms of muscle disease in early childhood. The clinical course was variable both between and within some families, but was most often slowly progressive. Some variability in the pattern of muscle involvement between the different families has also been observed.  相似文献   
88.
High-level synthesis is the process of automatically translating abstract behavioral models of digital systems to implementable hardware. Operation scheduling and hardware allocation are the two most important phases in the synthesis of circuits from behavioral specification. Scheduling and allocation can be formulated as an optimization problem. In this work, a unique approach to scheduling and allocation problem using the genetic algorithm (GA) is described. This approach is different from a previous attempt using GA (Wehn et al., IFIP Working Conference on Logic and Architecture Synthesis, Paris, 1990, pp. 47–56) in many respects. The main contributions include: (1) a new chromosomal representation for scheduling and for two subproblems of allocation; and (2) two novel crossover operators to generate legal schedules. In addition the application of tabu search (TS) to scheduling and allocation is also implemented and studied. Two implementations of TS are reported and compared. Both genetic scheduling and allocation (GSA) and tabu scheduling and allocation (TSA) have been tested on various benchmarks and results obtained for data-oriented control-data flow graphs are compared with other implementations in the literature. (A discussion on GSA was presented at the European Design Automation Conference Euro-DAC'94 in Grenoble, France, and TSA at the International Conference on Electronics, Circuits and Systems — ICECS'94 in Cairo, Egypt.) A novel interconnect optimization technique using the GA is also realized.  相似文献   
89.
The limb-girdle muscular dystrophies are a clinically and genetically heterogeneous group of disorders. We have studied two large inbred families of different ethnic origin and excluded linkage to LGMD2 on chromosome 15q and SCARMD on chromosome 13. Proceeding to a genomic linkage search, we have now identified linkage to markers D2S134 and D2S136 on chromosome 2p (maximum lod score 3.57 at zero recombination). The phenotype in the two families was similar, with onset in the pelvic girdle musculature in the late teens and usually relatively slow progression. This work identifies a second locus for autosomal recessive limb-girdle muscular dystrophy.  相似文献   
90.
Selective epitaxial growth (SEG) of silicon has not had widespread use as a dielectric isolation technology due to the near sidewall defects at the SiO2/Si interface. These defects are located in the first 1-2 μm of the SEG/sidewall SiO2 interface. Diode junctions intersecting the sidewall and 5 μm removed from the sidewall were fabricated in SEG material using thermally grown silicon dioxide (OX) and thermally nitrided thermal silicon dioxide (NOX) as the field insulating mask. Averaged over 16 devices of each type, diodes fabricated with NOX had much better low current I-V characteristics and minimum ideality factors (1.03) than diodes fabricated with OX field oxides (1.23). Junctions intersecting the NOX field insulator had nearly identical characteristics to bulk SEG  相似文献   
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