672 research outputs found
Should Carotid Endarterectomy be performed for Symptomatic Carotid Stenosis Pakistan?
Objective: The risk of stroke and death associated with carotid endarterctomy is operator dependant. Data regarding risks of this procedure are not available in Pakistan and therefore it is difficult to make accurate risk benefit analysis for individual patients. Our objective was to determine safety of carotid endarterectomy at an academic tertiary care center in Pakistan.
Methods: Patients who underwent carotid endarterectomy (CEA) at our hospital during a ten-year period were identified through ICD-9 coding system of the hospital medical records. Demographic features. associated medical problems and immediate postoperative complications were recorded and analyzed.
Results: Sixty-three carotid endarterectomies were performed on 59 patients. Ages range from 43 to 80 (mean 61±8) years; 53 were male and 10 were female. Common associated diseases among these patients were hypertension; 38 (64.4°/x), ischemic heart disease; 26 (44%), diabetes mellitus: 24 (40.7%); dyslipidemia; 19 (32.2%) and renal insufficiency; 13 (22%). Most common complication was neuropraxia (transient neuropathy) 5 (7.9%), followed by pneumonia and stroke; each in 3 (4.8%) patients. None of the strokes related to the surgical procedure were disabling. Two of the patients who had stroke, recovered fully within 17 weeks and one recovered partly but was independent in all daily activities of living (ADLs). One patient died following simultaneous coronary artery bypass graft (CABG) and CEA. The risk of stroke or death for patients undergoing CEA was high with simultaneous CABG (3/11, 27%) and low for patients undergoing CEA alone (1/52, 2%).
Conclusion: Carotid endarterectomy is a safe procedure in patients with symptomatic carotid stenosis at our hospital and should be performed, when indicated. (JPMA 53:589;2003)
Bosonic Reduction of Susy Generalized Harry Dym Equation
In this paper we construct the two component supersymmetric generalized Harry
Dym equation which is integrable and study various properties of this model in
the bosonic limit. In particular, in the bosonic limit we obtain a new
integrable system which, under a hodograph transformation, reduces to a coupled
three component system. We show how the Hamiltonian structure transforms under
a hodograph transformation and study the properties of the model under a
further reduction to a two component system. We find a third Hamiltonian
structure for this system (which has been shown earlier to be a bi-Hamiltonian
system) making this a genuinely tri-Hamiltonian system. The connection of this
system to the modified dispersive water wave equation is clarified. We also
study various properties in the dispersionless limit of our model.Comment: 21 page
Prevalence of Muscle Dysmorphia and Associated Health Activities in Male Medical Students in Karachi, Pakistan
Background: Muscle Dysmorphia (MD) is a subtype of body dysmorphic disorder (BDD) and is currently classified under anxiety disorders (subheading: Obsessive-compulsive disorder) in DSM 5. MD is hypothesized to affect the self-esteem and social outlook of the younger generation. MD shows a higher rate in males and may influence their self-confidence rendering them more prone towards using steroids, supplementary proteins and other drugs to alter their physical outlooks as shown in previous studies. This problem has been on the rise lately due to revolutionary advancement in the media and film industry and the abrupt changes about the standards of physical good looks and body shapes. With the lack of studies done in our population, our study will be helpful to consider the prevalence of the disease in our setting and increase awareness in the general public and clinicians. We hope to help clinicians/ therapists find better options in managing the disease.
Materials: We performed a cross-sectional study with a sample size of 246 medical school students in Karachi to collect data through self-administered questionnaires. We used the DSM 5 criteria for the diagnosis of BDD and additional questions on the presence of MD. Nutritional habits, exercise routines, use of supplements and drugs were also obtained for exploratory analysis.
Results: Our study predicted the prevalence of MD to be 25%. Other main findings included statistical significant associations between MD and the thoughts and practice of steroid use for muscularity.
Conclusion: MD is an underdiagnosed and often unrecognized disease that we believe has significant consequences for the young male population. Further work is needed on this in our part of the world. Our research, we believe, can be a stepping stone for further studies that would incorporate wider populations
Real Time Wireless Air Pollution Monitoring system
Air pollution has
significant influence on the concentration of
constituents in the atmosphere leading to effects like global warming
and acid rains. To avoid such adverse imbalances in the nature, an
air pollution monitoring system is utmost important. This paper
attempts
to develop an effective solution for pollution monitoring
using wireless sensor networks (WSN) on a real time basis namely
real time wireless air pollution monitoring system. Commercially
available discrete gas sensors for sensing concentration of gases l
ike
CO
2
, NO
2,
CO and O
2
are calibrated using appropriate calibration
technologies. These pre
-
calibrated gas sensors are then integrated
with the wireless sensor motes for field deployment at the campus and
the Hyderabad city using multi hop data aggregatio
n algorithm. A
light weight middleware and a web interface to view the live pollution
data in the form of numbers and charts from the test beds was
developed and made available from anywhere on the internet. Other
parameters like temperature and humidity w
ere also sensed along
with gas concentrations to enable data analysis through data fusion
techniques. Experimentation carried out using the developed wireless
air pollution monitoring system under different physical conditions
show that the system collects
reliable source of real time fine
-
grain
pollution data
Validation of fibre stress utilization model for modified ring spun yarns
To model the fibre stress utilization in modified ring spun yarns, we developed an analytical formula from the experimental data. The development of empirical formulae is carried out by using two different techniques, i.e., Cubic Spline and Artificial Neural Network methods. The experimental data of stress-strain curves of fibre and yarn has a large variation. To cope this variability, we used the smoothing spline technique to find the best-fit curve with respect to a reasonable smoothness. The best nonlinear smooth fitting can be used to extrapolate the experimental data beyond the breaking point. The modified ring spun yarns (compact, SIRO and SIRO-compact) with 20/1, 30/1 and 40/1 English count, produced from viscose staple fibre, were used to predict fibre stress utilization up to the yarn break by extrapolating the mean stress-strain curves of fibre and yarn by using the artificial neural network. Moreover, a new distribution function of fibre distribution in yarn has been proposed and successfully implemented for the prediction of fibre stress utilization in yarn. The new formulation helps to compute the fibre stress utilization in the yarn analytically. The validation of the proposed methodology is presented by comparing the numerical results with the experimental data. The predicted fibre stress utilization was in good agreement with the experimental fibre stress utilization for all types of modified ring spun yarns. It has been observed that SIRO-compact yarn exhibits improved fibre stress utilization as compared to SIRO and compact yarns. Moreover, the new distribution functions Gamma and Gaussian distribution were introduced in parallel with the Dirac delta function. In previous similar studies on ring, rotor and air-jet spun yarns, the proposed model can only predict the fibre stress utilization before the breakage point whereas the modified model, in this study, can predict the fibre stress utilization up to the breaking point
Security and Efficiency Analysis of the Hamming Distance Computation Protocol Based on Oblivious Transfer
open access articleBringer et al. proposed two cryptographic protocols for the computation of Hamming distance. Their first scheme uses Oblivious Transfer and provides security in the semi-honest model. The other scheme uses Committed Oblivious Transfer and is claimed to provide full security in the malicious case. The proposed protocols have direct implications to biometric authentication schemes between a prover and a verifier where the verifier has biometric data of the users in plain form.
In this paper, we show that their protocol is not actually fully secure against malicious adversaries. More precisely, our attack breaks the soundness property of their protocol where a malicious user can compute a Hamming distance which is different from the actual value. For biometric authentication systems, this attack allows a malicious adversary to pass the authentication without knowledge of the honest user's input with at most complexity instead of , where is the input length. We propose an enhanced version of their protocol where this attack is eliminated. The security of our modified protocol is proven using the simulation-based paradigm. Furthermore, as for efficiency concerns, the modified protocol utilizes Verifiable Oblivious Transfer which does not require the commitments to outputs which improves its efficiency significantly
Collective vs local measurements in qubit mixed state estimation
We discuss the problem of estimating a general (mixed) qubit state. We give
the optimal guess that can be inferred from any given set of measurements. For
collective measurements and for a large number of copies, we show that the
error in the estimation goes as 1/N. For local measurements we focus on the
simpler case of states lying on the equatorial plane of the Bloch sphere. We
show that standard tomographic techniques lead to an error proportional to
, while with our optimal data processing it is proportional to
.Comment: 4 pages, 1 figure, minor style changes, refs. adde
Synthetic biology open language visual (SBOL Visual) version 2.3
People who are engineering biological organisms often find it useful to communicate in diagrams, both about the structure of the nucleic acid sequences that they are engineering and about the functional relationships between sequence features and other molecular species. Some typical practices and conventions have begun to emerge for such diagrams. The Synthetic Biology Open Language Visual (SBOL Visual) has been developed as a standard for organizing and systematizing such conventions in order to produce a coherent language for expressing the structure and function of genetic designs. This document details version 2.3 of SBOL Visual, which builds on the prior SBOL Visual 2.2 in several ways. First, the specification now includes higher-level "interactions with interactions," such as an inducer molecule stimulating a repression interaction. Second, binding with a nucleic acid backbone can be shown by overlapping glyphs, as with other molecular complexes. Finally, a new "unspecified interaction" glyph is added for visualizing interactions whose nature is unknown, the "insulator" glyph is deprecated in favor of a new "inert DNA spacer" glyph, and the polypeptide region glyph is recommended for showing 2A sequences
A homozygous AKNA frameshift variant is associated with microcephaly in a Pakistani family
Primary microcephaly (MCPH) is a prenatal condition of small brain size with a varying degree of intellectual disability. It is a heterogeneous genetic disorder with 28 associated genes reported so far. Most of these genes encode centrosomal proteins. Recently, AKNA was recognized as a novel centrosomal protein that regulates neurogenesis via microtubule organization, making AKNA a likely candidate gene for MCPH. Using linkage analysis and whole-exome sequencing, we found a frameshift variant in exon 12 of AKNA (NM_030767.4: c.2737delG) that cosegregates with microcephaly, mild intellectual disability and speech impairment in a consanguineous family from Pakistan. This variant is predicted to result in a protein with a truncated C-terminus (p.(Glu913Argfs*42)), which has been shown to be indispensable to AKNA’s localization to the centrosome and a normal brain development. Moreover, the amino acid sequence is altered from the beginning of the second of the two PEST domains, which are rich in proline (P), glutamic acid (E), serine (S), and threonine (T) and common to rapidly degraded proteins. An impaired function of the PEST domains may affect the intracellular half-life of the protein. Our genetic findings compellingly substantiate the predicted candidacy, based on its newly ascribed functional features, of the multifaceted protein AKNA for association with MCPH
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