488 research outputs found
Closed Cell Aluminium Composite Foam for Crashworthiness Applications
Closed cell aluminium foams with various densities have been made through stir casting technique. The crucible temperature and melt temperature have been controlled to control the foaming temperature for controlling foam cell size and foam densities. The foam made has been then characterized for their micro-architectural characteristics as well as deformation responses. The crash of vehicle takes place at very high speed and therefore, the foams have been tested both at quasi-static and dynamic conditions. It is noted that at dynamic conditions the foams exhibit much higher strength and energy absorption. Then the foams have been filled manually inside the commercially available crash-box and tested using drop weight test methodology. The weight is varied up to 375 kg and speed is varied up to 55 km/h. The deformation behavior of bare foam blocks, foam filled crash box and empty crash boxes have been studied. It is observed that the foam synthesized through this technique is excellent for crash energy absorption. It is also noted that hardly any significant weight will be added into the vehicle. These closed cell foam has also the potential to be used in other transport sectors
A robust people detection, tracking, and counting system
The ability to track moving people is a key aspect of autonomous robot systems in real-world environments. Whilst for many tasks knowing the approximate positions of people may be sufficient, the ability to identify unique people is needed to accurately count people in the real world. To accomplish the people counting task, a robust system for people detection, tracking and identification is needed. This paper presents our approach for robust real world people detection, tracking and counting using a PrimeSense RGBD camera. Our past research, upon which we built, is highlighted and novel methods to solve the problems of sensor self-localisation, false negatives due to persons physically interacting with the environment, and track misassociation due to crowdedness are presented. An empirical evaluation of our approach in a major Sydney public train station (N=420) was conducted, and results demonstrating our methods in the complexities of this challenging environment are presented
Prevalence and risk factors of lower limb amputation in patients with end-stage renal failure on dialysis: a systematic review
Background: Renal dialysis has recently been recognised as a risk factor for lower limb amputation (LLA). However, exact rates and associated risk factors for the LLA are incompletely understood.
Aim: Prevalence and risk factors of LLA in end-stage renal failure (ESRF) subjects on renal dialysis were investigated from the existing literature.
Methods: Published data on the subject were derived from MEDLINE, PubMed, and Google Scholar search of English language literature from January 1, 1980, to July 31, 2015, using designated key words.
Results: Seventy studies were identified out of which 6 full-text published studies were included in this systematic review of which 5 included patients on haemodialysis alone and one included patients on both haemodialysis and peritoneal dialysis. The reported findings on prevalence of amputation in the renal failure on dialysis cohort ranged from 1.7% to 13.4%. Five out of the six studies identified diabetes as the leading risk factor for amputation in subjects with ESRF on renal dialysis. Other risk factors identified were high haemoglobin A1c, elevated c-reactive protein, and low serum albumin.
Conclusions: This review demonstrates high rate of LLA in ESRF patients receiving dialysis therapy. It has also identified diabetes and markers of inflammation as risk factors of amputation in ESRF subjects on dialysis
Enantioselective synthesis of bronchodilating agent (R)-Salmeterol<sup> #</sup>
1347-1352Synthesis of Ī²2-adrenoreceptor agonist bronchodilator (R)-Salmeterol has been described with good yields. The synthesis commenced from commercially available starting materials, 4-hydroxy benzaldehyde and phenylbutanoic acid. The features of the synthetic strategy are Wittig olefination and Sharpless asymmetric dihydroxylation
Phase Dependent Thermopower in Andreev Interferometers
We report measurements of the thermopower S of mesoscopic Andreev
interferometers, which are hybrid loops with one arm fabricated from a
superconductor (Al), and one arm from a normal metal (Au). S depends on the
phase of electrons in the interferometer, oscillating as a function of magnetic
flux with a period of one flux quantum (= h/2e). The magnitude of S increases
as the temperature T is lowered, reaching a maximum around T = 0.14 K, and
decreases at lower temperatures. The symmetry of S oscillations with respect to
magnetic flux depends on the topology of the sample.Comment: 4 pages, 4 figure
Spatiotemporal patterns of cholera hospitalization in Vellore, India
Systematically collected hospitalization records provide valuable insight into disease patterns and support comprehensive national infectious disease surveillance networks. Hospitalization records detailing patientās place of residence (PoR) can be utilized to better understand a hospitalās case load and strengthen surveillance among mobile populations. This study examined geographic patterns of patients treated for cholera at a major hospital in south India. We abstracted 1401 laboratory-confirmed cases of cholera between 2000ā2014 from logbooks and electronic health records (EHRs) maintained by the Christian Medical College (CMC) in Vellore, Tamil Nadu, India. We constructed spatial trend models and identified two distinct clusters of patient residenceāone around Vellore (836 records (61.2%)) and one in Bengal (294 records (21.5%)). We further characterized differences in peak timing and disease trend among these clusters to identify differences in cholera exposure among local and visiting populations. We found that the two clusters differ by their patient profiles, with patients in the Bengal cluster being most likely older males traveling to Vellore. Both clusters show well-aligned seasonal peaks in mid-July, only one week apart, with similar downward trend and proportion of predominant O1 serotype. Large hospitals can thus harness EHRs for surveillance by utilizing patientsā PoRs to study disease patterns among resident and visitor populations
Study on Efficacy of Expired and Active Forms of Various Antibiotics on Saccharomyces cerevisiae
Antibiotics are among the most frequently prescribed medications in modern medicines. The cell protection strategies in the organisms, development of resistance in previously susceptible microbes, the inevitable progression of microbes exposed to antibiotics to develop resistance, were the nesisities that ensures the need for continual cycles of discovery and development of new antibiotics. A large variety of antibiotics are available in the drug market today, several others being added regularly in combat with various pathogens that cause disease in humans as well as in animals. Our present study focused to investigate the change in efficacy of commonly used antibiotics such as amoxicillin, ampicillin, sparfloxacin, cefixime. We have collected antibiotics with before and after their expiry dates. A simple eukaryotic model organism Saccharomyces cerevisiae is used to study the comparative understanding of this microbe with these different antibiotics. In our investigation we found that response of Sacchromyces cerevisiae towards different antibiotics varied in its intricacies. Fresh forms of antibiotics have significantly inhibiting the growth of Saccharomyces cerevisiae as compared to expired forms. The observations revealed that expired forms of antibiotics loose their efficacy drastically
Mathematical practices and mathematical modes of enquiry: Same or different?
Background:
In this paper, I share a case study of a teacherās work on mathematics tasks in the context of a āmathematics for teachingā course aiming to develop mathematical content understandings and mathematical practices among primary teachers in one South African province. The course was developed in a national context of concerns about the nature and levels of primary teachersā mathematical knowledge. Theories viewing mathematical practices as fundamental, contrasted with those that view mathematical practices and mathematical content in more separate and āto be integratedā ways, are used to frame the analysis and ritically reflect on the findings.
Results: Data from this teacherās pre-test and selected course assessments and interactions suggest that while he was able to develop some aspects of the mathematical practices described in the literature, his overall orientation remained attuned to memorization and recall. Findings also pointed to an ongoing reliance on external validation of the ācorrectnessā of his answers.
Conclusions: The data suggest that the presence of elements of mathematical practices cannot be viewed as equivalent to the presence of mathematical modes of enquiry. The analysis presented in this paper suggests that while elements of mathematical practices can be developed, moving towards an encompassing orientation to
mathematical modes of enquiry may require more central focus on problem-solving approaches to achieve a change in orientation
- ā¦