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A Secure Key Management Framework for Heterogeneous Wireless Sensor Networks
No full textAbstract. A Wireless sensor network (WSN) is composed of numerous sensor nodes with both insecurely limited hardware and restricted communication capabilities. Thus WSNs suffer from some inherent weaknesses. Key management is an interesting subject in WSNs because it is the fundamental element for all security operations. A few key management models for heterogeneous sensor networks have been proposed in recent years. In this paper, we propose a new key management scheme based on elliptic curve cryptography and signcryption method for hierarchical heterogeneous WSNs. Our scheme as a secure infrastructure has superior sensor node mobility and network scalability. Furthermore, we propose both a periodic authentication and a new registration mechanism in our scheme due to prevention of sensor node compromising. Also, the proposed scheme does not increase the number of keys in sensor nodes and has a reasonable communication and computation overhead compared with the other schemes
INCIDENCE OF ANXIETY AND DEPRESSION IN WOMEN UNDERGOING HYSTERECTOMY
No full textABSTRACT Psychiatric morbidity due to anxiety and depression is high in young women undergoing hysterectomy for oncological, reasons both preoperatively and operatively. The decrease in anxiety post operatively occurred in a gradual way with a shift from severe to moderate and mild degree, but is persistent in 64% of patients 24 weeks post operatively in the absence of anxiolytics and psychotherapy. Incidence of depression preoperatively was 24% but declined to 14.4% 24 weeks postoperatively without treatment, psychiatric assistance is required after intervention
Optimizing Starch Concentrations in Dairy Rations
No full textAbstract Currently, many nutritionists consider only the total nonfiber carbohydrate (NFC) fraction when formulating rations for lactating dairy cows. Increasingly, we need to measure the components that comprise NFC (starch, sugars, soluble fiber, and β-glucans) and formulate rations that optimize the concentration of each component in the diet. Starch is the major NFC fraction in dairy cattle diets, and some research has attempted to determine optimal dietary concentrations of either NFC or starch. However, an optimal amount of dietary starch will be a function of several factors, including the inherent degradability of the starch source, processing method, amount of soluble protein, neutral detergent fiber (NDF) content, feeding method, and environment. Commonly, dietary starch recommendations range between 23 to 30% of ration dry matter (DM) depending on forage content of the diet. The basis for this range in recommendations is a combination of some research but mostly anecdotal and experience-based observations in the field. The purpose of this paper is to explore some of the key factors that influence the optimal content of dietary starch, particularly considering diets high in fibrous byproducts
Synthesis and Properties of AB-Type Semicrystalline Polyimides Prepared from Polyamic Acid Ethyl Ester Precursors
No full textABSTRACT: Three AB-type polyimides with para-, meta-and ortho-linked main chain units based on hydroquinone, resorcinol and catechol, were synthesized and characterized. The polyimides were prepared in two steps by the direct polycondensation reactions of isomeric monomers, 4-(4-aminophenoxy)diphenyl ether-3′,4′-dicarboxylic acid monoethyl ester (I p), 3-(4-aminophenoxy)diphenyl ether-3′,4′-dicarboxylic acid monoethyl ester (Im) and 2-(4-aminophenoxy)diphenyl ether-3′,4′-dicarboxylic acid monoethyl ester (Io), to form poly(amic acid ethyl ester)s followed by thermal or chemical imidization. The resultant polyimides were analyzed by tensile tests, thermogravimetry (TG), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and wide-angle X-ray diffraction measurements. It was shown that these AB-type polyimides were semicrystalline and the crystallinities were estimated to be 19-24%. These polyimides showed glass transition temperatures in the range of 178-198°C and melting transition temperatures of 308-393°C. DSC measurements suggested that the polyimide based on hydroquinone units crystallizes much faster than those based on resorcinol and catechol. The polyimide based on the fully para-ether linkages showed a single melting endotherm, whereas the polyimides containing metaand ortho-ether linkages exhibited bimodal melting behavior
Using Customized Navigational Models to Deliver more Efficient Interaction with Mobile Computing Devices on Construction Sites
No full textAbstract Mobile computing devices have started to become useful tools on construction sites. These devices can make large amounts of data available and support data collection tasks on a construction site. Even though battery life, computing power and data storage capacity have greatly improved and will probably not be limiting factors for mobile computing solutions, it is still difficult to interact with mobile computing devices efficiently. Some of the factors limiting efficient interaction are the size of the screen of a mobile computing device, the deficiency of a keyboard and the limited accuracy of the pointing device. The approach we pursue is to limit the interaction needed for specific tasks that are carried out using a mobile computing device. To do this we are working on developing Navigational Models, which reduce navigation through large data sets by grouping data entities closely together, according to the need to be accessed for a specific task. Moreover, Navigational Models appear to be a useful construct to enter and access data at the right level of detail, which they needed. In this paper, we discuss the need for more efficient interaction with mobile computing devices on construction sites and introduce Navigational Models
15+ MILLION TOP 1% MOST CITED SCIENTIST 12.2% AUTHORS AND EDITORS FROM TOP 500 UNIVERSITIES Chapter from the book Rapid Prototyping Technology -Principles and Functional Requirements
No full textPersonality changes and return to work after severe traumatic brain injury: a prospective study
No full textObjective: To evaluate predictors of non-return to work (nRTW) among social, demographic, clinical, and psychiatric variables after severe traumatic brain injury (TBI) in a cohort of Brazilian patients. Methods: Prospective study. Forty-three community-dwelling individuals treated at a Level I trauma center at the time of TBI were evaluated 18 months after trauma. Measures included DSM-IV-TR criteria for personality changes after TBI and Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I) to assess psychiatric diagnosis. Hospitalization variables included Glasgow Coma Scale scores, pupil examination findings, associated limb trauma, Marshall computed tomography classification, and blood glucose levels. Results: After multiple logistic regression analysis, only the diagnosis of personality changes was found to be independently associated with nRTW, with an adjusted odds ratio of 10.92 (p = 0.02, 95% confidence interval 1.41-84.28). Conclusions: In this study, personality changes were an independent predictor of nRTW after severe TBI. Ways to predict risk factors associated with personality changes after severe brain injury could aid in identification of early and effective interventions that might ease the burden associated with this condition