2,469 research outputs found
Charm Lifetimes and Mixing
A review of the latest results on charm lifetimes and D-mixing is presented.
The e+e- collider experiments are now able to measure charm lifetimes quite
precisely, however comparisons with the latest results from fixed-target
experiments show that possible systematic effects could be evident. The new
D-mixing results from the B-factories have changed the picture that is
emerging. Although the new world averaged value of y_CP is now consistent with
zero, there is still a very interesting and favoured scenario if the strong
phase difference between the Doubly-Cabibbo-suppressed and the
Cabibbo-flavoured D0 -> Kpi decay is large.Comment: Presented at the 9th International Symposium on Heavy Flavors,
Caltech, Pasadena, 10-13 Sept. 2001. To appear in proceeding
Review of charm and beauty lifetimes
A review of the latest experimental results on charm and beauty particle lifetimes is presented together with a brief summary of measurement methods used for beauty particle lifetime measurements. There have been significant updates to the D{sub s}{sup +}/D{sup 0}, B{sup +}/B{sub d}{sup 0} and {Lambda}{sub b}{sup 0}/B{sub d}{sup 0} lifetime ratios which have some theoretical implications. However more precise measurements are still needed before one can make conclusive statements about the theory used to calculate the particle lifetimes
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Performance of a beam monitor in the Fermilab Tevatron using synchrotron light
Synclite, the beam monitor in the Fermilab Tevatron using synchrotron light is described. The calibration, monitoring and performance of the system is discussed. Observation of some effects of long range beam-beam interactions seen in the beam monitor will be presented as well as a measurement of DC beam in the Tevatron
Microbial lysate upregulates host oxytocin
Neuropeptide hormone oxytocin has roles in social bonding, energy metabolism, and wound healing contributing to good physical, mental and social health. It was previously shown that feeding of a human commensal microbe Lactobacillus reuteri (L. reuteri) is sufficient to up-regulate endogenous oxytocin levels and improve wound healing capacity in mice. Here we show that oral L. reuteri-induced skin wound repair benefits extend to human subjects. Further, dietary supplementation with a sterile lysate of this microbe alone is sufficient to boost systemic oxytocin levels and improve wound repair capacity. Oxytocin-producing cells were found to be increased in the caudal paraventricular nucleus [PVN] of the hypothalamus after feeding of a sterile lysed preparation of L. reuteri, coincident with lowered blood levels of stress hormone corticosterone and more rapid epidermal closure, in mouse models. We conclude that microbe viability is not essential for regulating host oxytocin levels. The results suggest that a peptide or metabolite produced by bacteria may modulate host oxytocin secretion for potential public or personalized health goals.Published versio
Factors associated with adoption of the electronic health record system among primary care physicians
Background: A territory-wide Internet-based electronic patient record allows better patient care in different sectors. The engagement of private physicians is one of the major facilitators for implementation, but there is limited information about the current adoption level of electronic medical record (eMR) among private primary care physicians.
Objective: This survey measured the adoption level, enabling factors, and hindering factors of eMR, among private physicians in Hong Kong. It also evaluated the key functions and the popularity of electronic systems and vendors used by these private practitioners.
Methods: A central registry consisting of 4324 private practitioners was set up. Invitations for self-administered surveys and the completed questionnaires were sent and returned via fax, email, postal mail, and on-site clinic visits. Current users and non-users of eMR system were compared according to their demographic and practice characteristics. Studentâs t tests and chi-square tests were used for continuous and categorical variables, respectively.
Results: A total of 524 completed surveys (response rate 524/4405 11.90%) were collected. The proportion of using eMR in private clinics was 79.6% (417/524). When compared with non-users, the eMR users were younger (users: 48.4 years SD 10.6 years vs non-users: 61.7 years SD 10.2 years, P<.001); more were female physicians (users: 80/417, 19.2% vs non-users: 14/107, 13.1%, P=.013); possessed less clinical experience (with more than20 years of practice: users: 261/417, 62.6% vs non-user: 93/107, 86.9%, P<.001); fewer worked under a Health Maintenance Organization (users: 347/417, 83.2% vs non-users: 97/107, 90.7%, P<.001) and more worked with practice partners (users: 126/417, 30.2% vs non-users: 4/107, 3.7%, P<.001). Efficiency (379/417, 90.9%) and reduction of medical errors (229/417, 54.9%) were the major enabling factors, while patient-unfriendliness (58/107, 54.2%) and limited consultation time (54/107, 50.5%) were the most commonly reported hindering factors. The key functions of computer software among eMR users consisted of electronic patient registration system (376/417, 90.2%), drug dispensing system (328/417, 78.7%) and electronic drug labels (296/417, 71.0%). SoftLink Clinic Solution was the most popular vendor (160/417, 38.4%).
Conclusions: These findings identified several physician groups who should be targeted for more assistance on eMR installation and its adoption. Future studies should address the barriers of using Internet-based eMR to enhance its adoption
Background Subtraction Approach based on Independent Component Analysis
In this work, a new approach to background subtraction based on independent component analysis is presented. This approach assumes that background and foreground information are mixed in a given sequence of images. Then, foreground and background components are identified, if their probability density functions are separable from a mixed space. Afterwards, the components estimation process consists in calculating an unmixed matrix. The estimation of an unmixed matrix is based on a fast ICA algorithm, which is estimated as a Newton-Raphson maximization approach. Next, the motion components are represented by the mid-significant eigenvalues from the unmixed matrix. Finally, the results show the approach capabilities to detect efficiently motion in outdoors and indoors scenarios. The results show that the approach is robust to luminance conditions changes at scene
The incidence of all-cause, cardiovascular and respiratory disease admission among 20,252 users of lisinopril vs. perindopril: a cohort study
Background:
Major international guidelines do not offer explicit recommendations on any specific angiotensin-converting enzyme inhibitor (ACEI) agent over another within the same drug group. This study compared the effectiveness of lisinopril vs. perindopril in reducing the incidence of hospital admission due to all-cause, cardiovascular disease and respiratory disease.
Methods:
Adult patients who received new prescriptions of lisinopril or perindopril from 2001 to 2005 in all public hospitals and clinics in Hong Kong were included, and followed up for â„2â
years. The incidence of admissions due to all-cause, cardiovascular disease and respiratory disease were evaluated, respectively, by using Cox proportional hazard regression models. The regression models were constructed with propensity score matching to minimize indication biases.
Results:
A total of 20,252 eligible patients with an average age of 64.5â
years (standard deviation 15.0) were included. The admission rate at 24â
months within the date of index prescription due to any cause, cardiovascular disease and respiratory disease among lisinopril vs. perindopril users was 24.8% vs. 24.8%, 13.7% vs. 14.0% and 6.9% vs. 6.3%, respectively. Lisinopril users were significantly more likely to be admitted due to respiratory diseases (adjusted hazard ratios [AHR]â
=â
1.25, 95% CI 1.08 to 1.43, pâ
=â
0.002 at 12â
months; AHRâ
=â
1.17, 95% CI 1.04 to 1.31, pâ
=â
0.009 at 24â
months) and all causes (AHRâ
=â
1.12, 95% CI 1.05 to 1.19, pâ
<â
0.001 at 24â
months) than perindopril users.
Conclusions:
These findings support intra-class differences in the effectiveness of ACEIs, which could be considered by clinical guidelines when the preferred first-line antihypertensive drugs are recommended
The Curve of Compactified 6D Gauge Theories and Integrable Systems
We analyze the Seiberg-Witten curve of the six-dimensional N=(1,1) gauge
theory compactified on a torus to four dimensions. The effective theory in four
dimensions is a deformation of the N=2* theory. The curve is naturally
holomorphically embedding in a slanted four-torus--actually an abelian
surface--a set-up that is natural in Witten's M-theory construction of N=2
theories. We then show that the curve can be interpreted as the spectral curve
of an integrable system which generalizes the N-body elliptic Calogero-Moser
and Ruijsenaars-Schneider systems in that both the positions and momenta take
values in compact spaces. It turns out that the resulting system is not simply
doubly elliptic, rather the positions and momenta, as two-vectors, take values
in the ambient abelian surface. We analyze the two-body system in some detail.
The system we uncover provides a concrete realization of a Beauville-Mukai
system based on an abelian surface rather than a K3 surface.Comment: 22 pages, JHEP3, 4 figures, improved readility of figures, added
reference
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