1,013 research outputs found
The cardinality of the augmentation category of a Legendrian link
We introduce a notion of cardinality for the augmentation category associated
to a Legendrian knot or link in standard contact R^3. This `homotopy
cardinality' is an invariant of the category and allows for a weighted count of
augmentations, which we prove to be determined by the ruling polynomial of the
link. We present an application to the augmentation category of doubly
Lagrangian slice knots.Comment: 15 page
Augmentations are Sheaves
We show that the set of augmentations of the Chekanov-Eliashberg algebra of a
Legendrian link underlies the structure of a unital A-infinity category. This
differs from the non-unital category constructed in [BC], but is related to it
in the same way that cohomology is related to compactly supported cohomology.
The existence of such a category was predicted by [STZ], who moreover
conjectured its equivalence to a category of sheaves on the front plane with
singular support meeting infinity in the knot. After showing that the
augmentation category forms a sheaf over the x-line, we are able to prove this
conjecture by calculating both categories on thin slices of the front plane. In
particular, we conclude that every augmentation comes from geometry.Comment: 109 pages; v2: added Legendrian mirror example in section 4.4.4,
corrected typos and other minor changes; v3: accepted versio
Prevalence of internet addiction disorder in Chinese university students: A comprehensive meta-analysis of observational studies
Background and aims: Internet addiction disorder (IAD) is common in university students. A number of studies have examined the prevalence of IAD in Chinese university students, but the results have been inconsistent. This is a meta-analysis of the prevalence of IAD and its associated factors in Chinese university students.
Methods: Both English (PubMed, PsycINFO, and Embase) and Chinese (Wan Fang Database and Chinese National Knowledge Infrastructure) databases were systematically and independently searched from their inception until January 16, 2017.
Results: Altogether 70 studies covering 122,454 university students were included in the meta-analysis. Using the random-effects model, the pooled overall prevalence of IAD was 11.3% (95% CI: 10.1%–12.5%). When using the 8-item Young Diagnostic Questionnaire, the 10-item modified Young Diagnostic Questionnaire, the 20-item Internet Addiction Test, and the 26-item Chen Internet Addiction Scale, the pooled prevalence of IAD was 8.4% (95% CI: 6.7%–10.4%), 9.3% (95% CI: 7.6%–11.4%), 11.2% (95% CI: 8.8%–14.3%), and 14.0% (95% CI: 10.6%–18.4%), respectively. Subgroup analyses revealed that the pooled prevalence of IAD was significantly associated with the measurement instrument (Q = 9.41, p = .024). Male gender, higher grade, and urban abode were also significantly associated with IAD. The prevalence of IAD was also higher in eastern and central of China than in its northern and western regions (10.7% vs. 8.1%, Q = 4.90, p = .027).
Conclusions: IAD is common among Chinese university students. Appropriate strategies for the prevention and treatment of IAD in this population need greater attention
Pola Resistensi Kuman Mycobacterium tuberculosis Terhadap Obat Anti Tuberkulosis (OAT) di Propinsi Daerah Istimewa Yogyakarta
ABSTRACT
Tuberculosis (TB) remains the major public health problem worldwide, including Indonesia. To control the epidemic chain, TB patients need to be treated Anti-tuberculosis drugs (OAT). Improper medication leads to the resistance of one or more OAT regimen used for tuberculosis treatment. Resistance to OAT becomes the major problem in the treatment and control of tuberculosis infection chain. This research is aimed to describe the M. tuberculosis resistance to OAT, to analyze factors related to the resistance and sputum conversion at the end of the intensive phase, as well as to analyze the relation between M. tuberculosis OAT resistance and sputum conversion at the end of the intensive phase.
The study was conducted in Yogyakarta Province during the period July - October 2002. Tuberculosis patient over 15 years old with positive acid-fast bacilli (BTA) test in two or more sputum specimen were recruited in the health services. M. tuberculosis resistance test to INH, rifampicin, etambutol, and streptomycin were conducted in-vitro. Sputum conversion examination was done at the end of the intensive phase (the end of 2nd month of treatment). Factors such as nutritional status, disease history, contact history and treatment history were identifiecUisng questionnare. Univariate and bivariate statistical analysis were conducted.
-The resistance pattern of M.tuberculosis in Yogyakarta Province during July - October 2002 showed 61,35% patient resistance to INH, 46,2% to streptomycin and 30,8% to etambutol. No resistance to rifampicin was observed. A significant relationship was observed between the M. tuberculosis resistance to OAT and sputum conversion at the end of the intensive phase (p=0,000). It was concluded that the resistance pattern in Yogyakarta was dominated by resistance of M. tuberculosis to INH. No case of multiple drug resistance was identified in this study M. tuberculosis resistance to OAT was significantly related to the sputum conversion at the end af the intensive phase.
Keywords: tuberculosis âanti-tuberculosis drugs â resistance â sputumconversion - risk factor
- …