3,690 research outputs found
Scan mirror remote temperature sensing system and method
A remote temperature sensing system (10) for a scanning mirror (7). The system (10) includes a sensor which detects heat radiated by the mirror and provides a signal in response thereto. In the illustrative implementation, the system (10) includes a thermistor mounted within a housing. The housing is contoured to maximize the receipt of thermal energy thereby. A mounting assembly maintains the thermistor a predetermined nonzero distance from the scanning mirror (7). The invention includes a shroud (12) mounted on the mirror (7) for shielding the thermistor and a support tube connected to the thermistor housing on a first end and to a base on the second end thereof. The support tube is adapted to remain stationary within the shroud as the scanning mirror and the shroud rotate due to the scanning of the mirror. Wires are connected to the thermistor on a first end thereof and are wrapped around the support tube. The wires include a length of electrically conductive material having a resistivity which has a low sensitivity to temperature variations. The sensor output is processed in a conventional manner to provide an output indicative of the temperature of the mirror
Thermophysical and elastic properties of Cu50Zr50 and (Cu50Zr50)95Al5 bulk-metallic-glass-forming alloys
By employing a containerless high-temperature high-vacuum electrostatic levitation technique, the thermophysical properties, including the ratio between the specific heat capacity and the hemispherical total emissivity, the specific volume, and the viscosity, of Cu50Zr50 and (Cu50Zr50)95Al5 bulk-metallic-glass (BMG)-forming liquids have been measured. Compared with Cu50Zr50, the improved glass-forming ability of (Cu50Zr50)95Al5 can be attributed to its dense liquid structure and its high value of viscosity. Additionally, the relationship between the viscosity of various BMG forming liquids at the melting temperature and the elastic properties of the corresponding glasses at room temperature will be compared
Management preferences following radical inguinal orchidectomy for Stage I testicular seminoma in Australasia
A survey to evaluate the preferred patterns of management of Stage I seminoma was conducted during March 2001. The questionnaire was distributed by the Royal Australian and New Zealand College of Radiologists to all qualified radiation oncologists, 74 out of 170 responded. All performed a staging CT scan of the abdomen and pelvis. Thoracic imaging consisted of either chest X-ray (29%) or chest CT (38%) while 33% performed both. Fifty-four percent of radiation oncologists discussed surveillance with their patients but estimated that 5% or less would choose this option. The most commonly prescribed dose was 25 Gy in 15 or 20 fractions (79%). Sixty-five percent of respondents treated the para-aortic (PA) nodes alone. Forty-two of 48 clinicians treating the PA field reported a change in practice after publication of the Medical Research Council study in 1999. Of these, 40 and 23% perform CT scans of the pelvis annually and every 6 months. Thirty-one percent did no follow-up CT scan. Compared to a similar survey from North America, we are more likely to use PA fields and less likely to discuss surveillance. As in the USA, and in contrast to Canada, few patients choose surveillance. There is no consensus regarding the frequency of follow-up scans in either North America or Australasia.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75636/1/j.1440-1673.2002.01060.x.pd
Functional Hand Proportion is Approximated by the Fibonacci Series
The debatable relationship of functional human hand proportion with the Fibonacci series has remained an obscure scientific enigma short of clinical interest. The main difficulty of proving such a relationship lies in defining what should constitute true "functional" proportion. In this study, we re-evaluate this unique relationship using hand flexion creases as anatomical surrogates for the functional axes of joint rotation. Standardized desktop photocopies of palmar views of both hands in full digital extension and abduction were obtained from 100 healthy male volunteers of Chinese ethnicity. The functional axes were represented by the distal digital crease (distal interphalangeal joint, DIPJ), proximal digital crease (proximal interphalangeal joint, PIPJ), as well as the midpoint between the palmar digital and transverse palmar creases (metacarpophalangeal joint, MCPJ). The ratio of DIPJ-Fingertip:PIPJ-DIPJ:MCPJ-PIPJ (p3:p2:p1) were measured by two independent observers and represented as standard deviation about the mean, and then compared to the theoretical ratio of 1:1:2. Our results showed that, for the 2nd to 5th digits, the p2:p3 ratios were 0.97Ā±0.09, 1.10Ā±0.10, 1.04Ā±0.12 and 0.80Ā±0.08 respectively; whilst the p1:p2 ratios were 1.91Ā±0.17, 1.98Ā±0.14, 1.89Ā±0.16 and 2.09Ā±0.24 respectively. When the data were analyzed for all digits, they showed a combined p3:p2:p1 ratio of 1:0.98:2.01. In conclusion, our results suggest that functional human hand proportion, as defined by flexion creases, is approximated by the Fibonacci series
Fuzzy identity-based data integrity auditing for reliable cloud storage systems
This is the author accepted manuscript. The final version is available from the publisher via the DOI in this record.As a core security issue in reliable cloud storage, data integrity has received much attention. Data auditing protocols enable
a verifier to efficiently check the integrity of the outsourced data without downloading the data. A key research challenge associated
with existing designs of data auditing protocols is the complexity in key management. In this paper, we seek to address the complex
key management challenge in cloud data integrity checking by introducing fuzzy identity-based auditing-the first in such an approach,
to the best of our knowledge. More specifically, we present the primitive of fuzzy identity-based data auditing, where a userās identity
can be viewed as a set of descriptive attributes. We formalize the system model and the security model for this new primitive. We then
present a concrete construction of fuzzy identity-based auditing protocol by utilizing biometrics as the fuzzy identity. The new protocol
offers the property of error-tolerance, namely, it binds private key to one identity which can be used to verify the correctness of a
response generated with another identity, if and only if both identities are sufficiently close. We prove the security of our protocol based
on the computational Diffie-Hellman assumption and the discrete logarithm assumption in the selective-ID security model. Finally, we
develop a prototype implementation of the protocol which demonstrates the practicality of the proposal.This work is
supported by the National Natural Science Foundation of
China (61501333,61300213,61272436,61472083), the Fundamental
Research Funds for the Central Universities under
Grant ZYGX2015J05
MTHFR C677T polymorphism, homocysteine and B vitamins status in a sample of Chinese and Malay subjects in Universiti Putra Malaysia.
INTRODUCTION:
Methylenetetrahydrofolate reductase (MTHFR) C677T is involved in folate and homocysteine metabolism. Disruption in the activity of this enzyme will alter their levels in the body.
METHODOLOGY:
This study assessed MTHFR C677T polymorphism and its relationship with serum homocysteine and B-vitamins levels in a sample of Chinese and Malays subjects in UPM, Serdang. One hundred subjects were randomly selected from among the university population. Folate, vitamin B12, B6, and homocysteine levels were determined using MBA, ECLIA, and HPLC, respectively. PCR coupled with HinfI digestion was used for detection of MTHFR C677T polymorphism.
RESULTS:
The frequency of T allele was higher in the Chinese subjects (0.40) compared to the Malay (0.14). Folate, vitamin B12 and B6 levels were highest in the wild genotype in both ethnic groups. Subjects with heterozygous and homozygous genotype showed the highest homocysteine levels. The serum folate and homocysteine were mainly affected by homozygous genotype.
CONCLUSION:
MTHFR C677T polymorphism plays an important role in influencing the folate and homocysteine metabolism
Effect of worksheet scaffolds on student learning in problem-based learning
The purpose of this study was to investigate the effect of worksheets as a scaffolding tool on studentsā learning achievement in a problem-based learning (PBL) environment. Seventeen PBL classes (NĀ =Ā 241) were randomly assigned to two experimental groupsāone with a worksheet provided and the other without. Studentsā learning of the topic at hand was evaluated by comparing results from pre- and post-lesson concept recall tests. We also obtained information about studentsā perceptions of factors impacting their learning using a Learning Impact Questionnaire. The data was analyzed by means of analyses of variance. Results of the study indicated that there was no statistically significant difference between the levels of understanding for both groups of students. In addition, survey results revealed that the strongest factor perceived by students to impact their learning in a PBL context is the tutor followed by team and class dynamics, while the influence of the worksheet was rated lowest. These findings suggest that scaffolds such as worksheets may not play a significant role in enhancing studentsā learning within the social constructivist framework of problem-based learning. On the other hand, the importance of the role of tutor and collaborative small group learning which are key features of PBL is reinforced
On-Demand Power Source for Medical Electronic Implants: Acousto-Mechanical Vibrations from Human Vocal Folds
For use in vibration-driven power generation, we have quantitatively characterized the acousto-mechanical vibrations that propagate from the human vocal folds through the neck and head along the skeletal frames. We have used five MEMS accelerometers to characterize the acousto-mechanical vibrations present in various situations. The acousto-mechanical
vibrations excite vibration-driven energy harvesters at their resonance frequencies between 90-300 Hz and generate up to 0.15 mW/cm^3 on demand
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