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1.
Clean Technologies and Environmental Policy - Biochar has caught great attention over the last decade, yielding a large number of publications in a broad range of disciplines. This scientometric...  相似文献   
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OBJECTIVES: Numerous reports have established the association of Helicobacter pylori and recurrent abdominal pain in children. We investigated the clinical, bacteriological and therapeutic features of our patients seen over a 1 year period. METHODS: We investigated 121 children during 1992 in Hospital Saint Vincent-de-Paul, Paris. At endoscopy, biopsies were taken and sent for histology and bacteriology and urease testing. A decision regarding treatment by amoxicillin and metronidazol was made after positive results of bacteriology and/or histology. RESULTS: Heliobacter pylori was found in 47 antral biopsies after pathology examination with Giemsa staining alone 16 times, bacterial culture 9 times and both methods 22 times. Abdominal pain was the prominent symptom, occurring in 35.5% of Helicobacter pylori+patients. In 25 of the positive negative patients, a nodular gastritis was observed (53.1%) and in 27.6% of them a weight loss or a delay in weight gain. Few patients became after combined treatment with amoxicillin and metronidazol whereas eradication rates after triple therapy with amoxicillin-metronidazol and H2 antagonist or proton pump blocker were higher. CONCLUSION: Helicobacter pylori related gastritis is a common cause of abdominal complaints in children. The most common symptom is recurrent abdominal pain. Antral nodularity is a peculiar endoscopic finding in children. Two-drug therapy associating amoxicillin-metronidazol is often ineffective to eradicate the bacteria whereas eradication rates after triple therapy amoxicillin-metronidazol and H2 antagonist or proton pump blocker are higher.  相似文献   
4.
The chemical composition and nutritional quality of tehineh, a paste of dehulled roasted sesame seeds, from Saudi Arabia and other countries, were studied. Results showed 24.7% protein, 58.9% fat, 2.3% fiber, 3.0% ash and <1.0% moisture. The tehineh contained relatively high amounts (mg/100 g) of P (692), Mg (362), Fe (7.19), Cu (1.96), Mn (1.46) and Zn (7.82) and low amounts of Ca (61) and Se (0.05). Gas-liquid chromatography (GLC) analysis of the oil revealed percentages of 42.4 for oleic, 39.7 for linoleic, 9.8 for palmitic and 6.4 for stearic acid. Lysine was the only limiting amino acid with a chemical score of 64, while the sulphur-containing amino acids (methionine + cystine) and tryptophan were present in amounts exceeding the requirement of the FAO/WHO (1973) reference protein. The in vitro protein digestibility (IVPD) value of 83.3% and the calculated protein efficiency ratio (C-PER), 2.14, were slightly higher than those of sesame seeds and both values were lower than the IVPD and C-PER of 90.0% and 2.50, respectively, for ANRC casein.  相似文献   
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In smart environments, pervasive computing contributes in improving daily life activities for dependent people by providing personalized services. Nevertheless, those environments do not guarantee a satisfactory level for protecting the user privacy and ensuring the trust between communicating entities. In this study, we propose a trust evaluation model based on user past and present behavior. This model is associated with a lightweight authentication key agreement protocol (Elliptic Curve-based Simple Authentication Key Agreement). The aim is to enable the communicating entities to establish a level of trust and then succeed in a mutual authentication using a scheme suitable for low-resource devices in smart environments. An innovation in our trust model is that it uses an accurate approach to calculate trust in different situations and includes a human-based feature for trust feedback, which is user rating. Finally, we tested and implemented our scheme on Android mobile phones in a smart environment dedicated for handicapped people.  相似文献   
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The Accelerated Life Testing (ALT) has been used for a long time in several fields to obtain information on the reliability of product components and materials under operating conditions in a much shorter time. One of the main purposes of applying ALT is to estimate the failure time functions and reliability performance under normal conditions. This paper concentrates on the estimation procedures under ALT and how to select the best estimation method that gives accurate estimates for the reliability function. For this purpose, different estimation methods are used, such as maximum likelihood, least squares (LS), weighted LS, and probability weighted moment. Moreover, the reliability function under usual conditions is predicted. The estimation procedures are applied under the family of the exponentiated distributions in general, and for the exponentiated inverted Weibull (EIW) as a special case. Numerical analysis including simulated data and a real life data set is conducted to compare the performances between these four methods. It is found that the ML method gives the best results among other estimation methods. Finally, a comparison between the EIW and the Inverted Weibull (IW) distributions based on a real life data set is made using a likelihood ratio test. It is observed that the EIW distribution can provide better fitting than the IW in case of ALT. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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This paper presents a modular system for both abnormal event detection and categorization in videos. Complementary normalcy models are built both globally at the image level and locally within pixels blocks. Three features are analyzed: (1) spatio-temporal evolution of binary motion where foreground pixels are detected using an enhanced background subtraction method that keeps track of temporarily static pixels; (2) optical flow, using a robust pyramidal KLT technique; and (3) motion temporal derivatives. At the local level, a normalcy MOG model is built for each block and for each flow feature and is made more compact using PCA. Then, the activity is analyzed qualitatively using a set of compact hybrid histograms embedding both optical flow orientation (or temporal gradient orientation) and foreground statistics. A compact binary signature of maximal size 13 bits is extracted from these different features for event characterization. The performance of the system is illustrated on different datasets of videos recorded on static cameras. The experiments show that the anomalies are well detected even if the method is not dedicated to one of the addressed scenarios.  相似文献   
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Undergraduate engineering programs in fourteen countries are surveyed to determine the status of engineering education outside the United States and to analyze the implications for the ideal engineering program of the future here in the United States. The items surveyed include the number of years required to obtain an engineering degree, title of the engineering degree, high school preparation for engineering programs, cost of education, completion rates for engineering degrees, entrance requirements, mathematical requirements, and support for laboratory work. The most notable aspects of engineering education outside the United States are:
  • ? Stronger high school preparation and requirements in mathematics and science
  • ? Longer period of time required for an engineering degree
  • ? Advanced level of mathematics required in engineering programs
  • ? Low cost of education
It appears that in most countries engineering education is more intense and rigorous than in the United States. In formulating the ideal engineering program of the future we must be sensitive to competing programs in the rest of the world.  相似文献   
9.
This paper presents a comparison study of the computational complexity of the general job shop protocol and the more structured flow line protocol in a flexible manufacturing system. It is shown that the representative problem of finding resource invariants is NP-complete in the case of the job shop, while in the flow line case it admits a closed form solution. The importance of correctly selecting part flow and job routing protocols in flexible manufacturing systems to reduce complexity is thereby conclusively demonstrated  相似文献   
10.
Abdallah OY 《Meat science》1983,8(4):301-315
The left sides of the carcasses of twelve Egyptian buffalo, nine half Friesian (♂ Friesian x ♀ Egyptian Baladi) and nine three-quarter Friesian (♂ x ♀ half-Friesian) bulls, serially slaughtered between 161 and 560 kg for buffaloes and between 176 and 448 kg for cattle, were used to describe the growth and distribution of individual muscles and muscle groups.

Genotype-group differences in the relative rate of growth were not significant in 85 of 89 muscles and in 8 of 9 muscle groups. The pooled within-group growth coefficients of individual muscles revealed different increasing growth gradients, i.e. disto-proximal in both limbs, mediolateral in the proximal pelvic limb, from elbow flexors to shoulder flexors in the proximal thoracic limb, caudo-cranial in the trunk and from hypaxial to epaxial muscles around the spinal column. The relative growth was lowest in the distal part of the limbs and highest in the anterior part of the carcass (SMG 7 and 8), with the loin and abdominal muscle groups growing at a rate similar to that of the total muscle. The neck and thorax muscle group grew at a higher rate in Friesian crosses than in buffaloes.

Genotype-group differences in the weight of each muscle relative to total side muscle (TSM) were significant in 50 of 89 muscles. Of the 50 muscles (constituting around 59% of TSM), 24 (approximately 44% of TSM) were from the expensive muscle groups. As compared with the most different Friesian cross (base = 100) at equal TSM, buffaloes had higher weight of muscle in the hindlimb (107·5% proximally; 106·3% distally) and forelimb (120·0% proximally: 104·6% distally) and significantly less weight of the muscle groups forming the abdominal wall (79·8%) and connecting the forelimb to the thorax (89·1%) and to the neck (90·7%). The weight of the combined expensive groups was significantly greater in buffaloes than in cattle (maximum difference = 1·8 kg) with a tendency for buffaloes to have relatively less of the tender muscles surrounding the spinal column.  相似文献   

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