482 research outputs found
Dynamic Information Flow Tracking on Multicores
Dynamic Information Flow Tracking (DIFT) is a promising technique for detecting software attacks. Due to the computationally intensive nature of the technique, prior efficient implementations [21, 6] rely on specialized hardware support whose only purpose is to enable DIFT. Alternatively, prior software implementations are either too slow [17, 15] resulting in execution time increases as much as four fold for SPEC integer programs or they are not transparent [31] requiring source code modifications. In this paper, we propose the use of chip multiprocessors (CMP) to perform DIFT transparently and efficiently. We spawn a helper thread that is scheduled on a separate core and is only responsible for performing information flow tracking operations. This entails the communication of registers and flags between the main and helper threads. We explore software (shared memory) and hardware (dedicated interconnect) approaches to enable this communication. Finally, we propose a novel application of the DIFT infrastructure where, in addition to the detection of the software attack, DIFT assists in the process of identifying the cause of the bug in the code that enabled the exploit in the first place. We conducted detailed simulations to evaluate the overhead for performing DIFT and found that to be 48 % for SPEC integer programs
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Sonography of Affected and Unaffected Shoulders in Hemiplegic Patients: Analysis of the Relationship Between Sonographic Imaging Data and Clinical Variables
Objective To explore the relationship between a number of clinically relevant variables and sonographic imaging data in respect to the level of impairment experienced in the affected and unaffected shoulders of hemiplegic stroke patients. Method Fifty-one hemiplegic stroke patients (32 males, 19 females; 29 right-sided hemiplegics, 22 left-sided hemiplegics) participated in this study. A musculoskeletal radiologist conducted a sonographic exam on both the affected and unaffected shoulders of all patients and two physicians classified the severity of the injury on a six-point rating scale. Clinical variables including age, sex, duration of injury, spasticity and muscle power of the hemiplegic side, and level of functional activity of the shoulder were assessed. Results The sonographic rating scores of hemiplegic shoulders were positively correlated with age (p<0.01) and negatively correlated with level of muscle spasticity (p<0.05). The sonographic rating scores of unaffected shoulders were positively correlated with duration of injury (p<0.01). Affected shoulders received sonographic rating scores that reflected significantly more impairment than those of unaffected shoulders (p<0.001), and premorbid handedness did not affect the relationship between impairment rating and shoulder injury status. Conclusion Hemiplegic stroke influences not only affected shoulders, but also unaffected sides. Proper management of spasticity, enhancement of motor recovery, and avoidance of unaffected shoulder overuse should be considered to prevent shoulder problems following strokes which result in hemiplegia
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The Nerve/Tunnel Index: A New Diagnostic Standard for Carpal Tunnel Syndrome Using Sonography
ObjectivesāTo define the relationship between body indices of healthy adults and cross-sectional areas of the carpal tunnel and median nerve and to obtain the nerve/tunnel index, which represents a new standard for diagnosing carpal tunnel syndrome using sonography. MethodsāBody indices (height, weight, and body mass index) were analyzed in 60 healthy adults, and electromyography and sonography were also performed. The crosssectional areas of the proximal and distal median nerve and carpal tunnel were obtained by sonography. The proximal and distal nerve/tunnel indices were obtained by calculating the ratio between the proximal and distal cross-sectional areas of the median nerve to those of the carpal tunnel and multiplying the value by 100. ResultsāAlthough the proximal cross-sectional areas of the median nerve and body indices showed statistically significant relationships with weak positive correlations, the proximal and distal areas of the carpal tunnel showed relatively stronger correlations with body indices. Between sexes, there were significant differences in the proximal median nerve cross-sectional area (mean Ā± SD: male, 10.48 Ā± 3.21 mm2; female, 8.81 Ā± 3.21 mm2; P < .05) and proximal carpal tunnel area (male, 182.50 Ā± 21.15 mm2; female, 151.23 Ā± 21.14 mm2; P < .05). There was no difference in the proximal nerve/tunnel index (male, 5.80% Ā± 1.72%; female, 5.91% Ā± 1.63%). There was a statistically significant difference in the distal carpal tunnel cross-sectional area (male, 138.90 Ā± 20.95 mm2; female, 121.50 Ā± 18.99 mm2; P < .05) between sexes, but the distal median area (male, 9.99 Ā± 3.42 mm2; female, 8.46 Ā± 1.84 mm2) and distal nerve/tunnel index (male, 7.15% Ā± 2.00%; female, 7.01% Ā± 1.38%) showed no significant differences. The proximal index was significantly higher than the distal index (proximal, 5.85% Ā± 1.66%; distal, 7.08% Ā± 1.71%). ConclusionsāThe nerve/tunnel index is unaffected by body indices or sex and thus may be a useful and objective standard for diagnosing carpal tunnel syndrome
Synergistic Effects of Hyaluronate - Epidermal Growth Factor Conjugate Patch on Chronic Wound Healing
The proteolytic microenvironment in the wound area reduces the stability and the half-life of growth factors in vivo, making difficult the topical delivery of growth factors. Here, epidermal growth factor (EGF) was conjugated to hyaluronate (HA) to improve the long-term stability against enzymatic degradation and the therapeutic effect by enhancing the biological interaction with HA receptors on skin cells. After the synthesis of HA-EGF conjugates, they were incorporated into a patch-type formulation for the facile topical application and sustained release of EGF. According to ELISA, the HA-EGF conjugates showed a long-term stability compared with native EGF. Furthermore, HA-EGF conjugates appeared to interact with skin cells through two types of HA and EGF receptors, resulting in a synergistically improved healing effect. Taken together, we could confirm the feasibility of HA-EGF conjugates for the transdermal treatment of chronic wounds.11Ysciescopu
Novel twin-roll-cast Ti/Al clad sheets with excellent tensile properties
Pure Ti or Ti alloys are recently spot-lighted in construction industries because they have excellent resistance to corrosions, chemicals, and climates as well as various coloring characteristics, but their wide applications are postponed by their expensiveness and poor formability. We present a new fabrication process of Ti/Al clad sheets by bonding a thin Ti sheet on to a 5052 Al alloy melt during vertical-twin-roll casting. This process has merits of reduced production costs as well as improved tensile properties. In the as-twin-roll-cast clad sheet, the homogeneously cast microstructure existed in the Al alloy substrate side, while the Ti/Al interface did not contain any reaction products, pores, cracks, or lateral delamination, which indicated the successful twin-roll casting. When this sheet was annealed at 350 degrees C-600 degrees C, the metallurgical bonding was expanded by interfacial diffusion, thereby leading to improvement in tensile properties over those calculated by a rule of mixtures. The ductility was also improved over that of 5052-O Al alloy (25%) or pure Ti (25%) by synergic effect of homogeneous deformation due to excellent Ti/Al bonding. This work provides new applications of Ti/Al clad sheets to lightweight-alloy clad sheets requiring excellent formability and corrosion resistance as well as alloy cost saving.112Ysciescopu
A Study on the Thermal Characteristics of the Epoxy Insulator in the Stop Joint Box of HTS Power Cable
AbstractThe HTS power cable is cooled by the circulation of liquid nitrogen. The cooling capacity of refrigerator increases with cable length. As the length of power cable increases, a joint box should be installed to reduce the cooling capacity and pressure drop for unit cooling system. The type of joint box can be divided into two groups. There are NJB(Normal Joint Box) and SJB(Stop Joint Box). Generally, SJB can separate each cooling system. In case of long distance DC cable, it is necessary to separate the cooling line in the regular distance of cooling system so SJB should be used. However, SJB, which has a difference from the insulation method of existing joint box, uses solid electrical insulation method. At the primary cooling time, thermal stress is generated by the temperature difference between the internal and external epoxy. So to prevent the damage stress analysis is required for the electrical insulation structure of SJB. In this paper, using the FEM analysis we study the cooling method and optimal shape of SJB to reduce the thermal stress result from temperature difference during the cooling time
Effect of Bisphosphonates on Anodized and HeatĆ¢ Treated Titanium Surfaces: An Animal Experimental Study
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141247/1/jper1035.pd
Analysis of Initial Baseline Clinical Parameters and Treatment Strategy Associated with Medication Failure in the Treatment of Benign Prostatic Hyperplasia in Korea
Purpose To analyze the baseline clinical factors and medication treatment strategy used in cases with medication treatment failure of benign prostatic hyperplasia (BPH). Methods From January 2006 to December 2009, 677 BPH patients with at least 3 months of treatment with medication were enrolled. We analyzed clinical factors by medication failure (n=161) versus maintenance (n=516), by prostate size (less than 30 g, n=231; 30 to 50 g, n=244; greater than 50 g, n=202), and by prostate-specific antigen (PSA) levels (less than 1.4 ng/mL, n=324; more than 1.4 ng/mL, n=353). Results Age, combination medication rate, PSA, and prostate volume were statistically different between the medication treatment failure and maintenance groups. By prostate size, the PSA and medication failure rates were relatively higher and the medication period was shorter in patients with a prostate size of more than 30 g. The combination medication rate was higher in patients with a prostate size of more than 50 g. The medication failure rate and prostate volume were higher in patients with a PSA level of more than 1.4 ng/mL. However, the combination treatment rate was not significantly different in patients with a PSA level lower than 1.4 ng/mL. Suggestive cutoffs for combination medication are a prostate volume of 34 g and PSA level of 1.9 ng/mL. Conclusions The clinical factors associated with medication failure were age, treatment type, and prostate volume. Combination therapy should be considered more in Korea in patients with a PSA level higher than 1.4 ng/mL and a prostate volume of between 30 and 50 g to prevent medication failure
Chlorine Dioxide Gas Retain Postharvest Quality and Shelf Life of Tomato During Modified Atmosphere Packaging Storage
While surface sterilization can minimize the postharvest loss of fruits and vegetables, it depends on concentration, treatment duration, storage condition, and crops. This study was conducted to investigate the consequences of chlorine dioxide (ClO2) gas on post-harvest quality and shelf life of tomato fruits during the modified atmosphere packaging storage. Tomato fruits of light red maturity stage were harvested at Gangwon province in the Republic of Korea. Fruits were dipped in fungal suspension and, afterward, some of them were sterilized with NaOCl, while others were sterilized with ClO2 gas. On the final storage day, the 5 ppm ClO2 gas 12 hours treated tomato fruits showed the least carbon dioxide and ethylene, and the utmost oxygen concentration. The least fresh weight loss, prolonged shelf life and the most suppressed fungal incidence were obtained by the 5 ppm ClO2 gas 12 hours treatment. As compared to other treatments, the 5 ppm ClO2 gas 12 hours treatment yielded higher firmness, titratable acidity and vitamin C, and lower soluble solids. Therefore, the 5 ppm ClO2 gas 12 hours treatment may be useful to prevent fungal incidence as well as to retain the postharvest quality and increase the shelf life of tomato fruits
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