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51.

Presentation attacks are becoming a serious threat to one of the most common biometric applications, namely face recognition (FR). In recent years, numerous methods have been presented to detect and identify these attacks using publicly available datasets. However, such datasets are often collected in controlled environments and are focused on one specific type of attack. We hypothesise that a model’s accurate performance on one or more public datasets does not necessarily guarantee generalisation across other, unseen face presentation attacks. To verify our hypothesis, in this paper, we present an experimental framework where the generalisation ability of pre-trained deep models is assessed using four popular and commonly used public datasets. Extensive experiments were carried out using various combinations of these datasets. Results show that, in some circumstances, a slight improvement in model performance can be achieved by combining different datasets for training purposes. However, even with a combination of public datasets, models still could not be trained to generalise to unseen attacks. Moreover, models could not necessarily generalise to a learned format of attack over different datasets. The work and results presented in this paper suggest that more diverse datasets are needed to drive this research as well as the need for devising new methods capable of extracting spoof-specific features which are independent of specific datasets.

  相似文献   
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PTH is a potent bone anabolic factor, and its combination with antiresorptive agents has been proposed as a therapy for osteoporosis. We tested the effects of PTH, alone and in combination with the novel antiresorptive agent OPG, in a rat model of severe osteopenia. Sprague Dawley rats were sham-operated or ovariectomized at 3 months of age. Rats were untreated for 15 months, at which time ovariectomy had caused significant decreases in bone mineral density in the lumbar vertebrae and femur. Rats were then treated for 5.5 months with vehicle (PBS), human PTH-(1-34) (80 microg/kg), rat OPG (10 mg/kg), or OPG plus PTH (all three times per wk, sc). Treatment of ovariectomized rats with OPG or PTH alone increased bone mineral density in the lumbar vertebrae and femur, whereas PTH plus OPG caused significantly greater and more rapid increases than either therapy alone (P < 0.05). OPG significantly reduced osteoclast surface in the lumbar vertebrae and femur (P < 0.05 vs. sham or ovariectomized), but had no effect on osteoblast surface at either site. Ovariectomy significantly decreased the mechanical strength of the lumbar vertebrae and femur. In the lumbar vertebrae, OPG plus PTH was significantly more effective than PTH alone at reversing ovariectomy-induced deficits in stiffness and elastic modulus. These data suggest that OPG plus PTH represent a potentially useful therapeutic option for patients with severe osteoporosis.  相似文献   
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ObjectiveThere is debate whether infection with Helicobacter (H.) pylori, the main inducer of chronic atrophic gastritis (CAG), is a risk factor for cardiovascular disease and premature mortality.MethodsSerological measurements of H. pylori infection and pepsinogen (PG) I and II were obtained in a population-based German cohort of 9953 older adults (50–74 years). Cox regression was employed to estimate hazard ratios (HR) and 95% confidence intervals (CI) for myocardial infarction, stroke, cardiovascular and all-cause mortality during five-year follow-up.ResultsAccording to serology, 4977 participants (51.9%) were infected with H. pylori (2604 with cytotoxin-associated gene A (cagA) strains) and 541 (5.7%) had CAG (PGI < 70 ng/mL and PGI/PGII < 3). During follow-up, 540 participants died (163 from cardiovascular causes), 170 experienced a primary myocardial infarction and 241 had a stroke. Neither cytotoxin-associated gene A (cagA) negative nor cagA positive H. pylori infections were associated with an increased risk for myocardial infarction, stroke or all-cause mortality. Intriguingly, infection with cagA positive H. pylori strains was inversely associated with cardiovascular mortality (HR, 0.62; CI: 0.41–0.94). No statistically significant associations were observed for the small group of participants with CAG, but point estimates of adjusted HRs for myocardial infarction, stroke and cardiovascular mortality were all below 1 (0.71, 0.59 and 0.65, respectively).ConclusionsOur results do not support the hypothesis that H. pylori infection or CAG are risk factors for cardiovascular disease or mortality and instead suggest an inverse relationship of cagA positive H. pylori infection with fatal cardiovascular events.  相似文献   
55.

Purpose

Despite continuously improving therapies, gastric cancer still shows poor survival in locally advanced stages with local recurrence rates of up to 50% and peritoneal recurrence rates of 17% after curative surgery. We performed a systematic review with meta-analyses to clarify whether positive intraperitoneal cytology (IPC) indicates a high risk of disease recurrence and poor overall survival in gastric cancer.

Methods

Multiple databases were searched in December 2014 to identify studies on the prognostic significance of positive intraperitoneal cytology in gastric cancer, including: Medline, Biosis, Science Citation Index, Embase, CCMed and publisher databases. Hazard ratios (HR) and associated 95% confidence intervals (CI) were extracted from the identified studies. A meta-analysis was performed using a random-effects model on overall survival, disease-free survival and peritoneal recurrence free survival.

Results

A total of 64 studies with a cumulative sample size of 12,883 patients were included. Cytology, quantitative real time polymerase chain reaction (PCR) or both were performed in 35; 21 and 8 studies, respectively. Meta analyses revealed free intraperitoneal tumor cells (FITC) to be associated with poor overall survival in univariate (HR 3.27; 95% CI 2.82 - 3.78]) and multivariate (HR 2.45; 95% CI 2.04 - 2.94) analysis and poor peritoneal recurrence free survival in univariate (4.15; 95% CI 3.10 - 5.57) and multivariate (3.09; 95% CI 2.02 - 4.71) analysis. Subgroup analysis showed this effect to be independent of the detection method, Western or Asian origin or the time of publication.

Conclusions

FITC oder positive peritoneal cytology is associated with poor survival and increased peritoneal recurrence in gastric cancer.  相似文献   
56.
Two regions (Jimma and Dire Dawa) in Ethiopia were investigated for the presence of soft ticks. Although no Ornithodoros spp. ticks were collected during this survey, published records of their existence in Ethiopia were found. An overwhelming infestation of Argas persicus was revealed in a village located adjacent to Dire Dawa. These ticks primarily were feeding on poultry, but were also biting humans. Furthermore, hard ticks were collected from livestock and companion animals in these regions.Collected ticks were assessed for Borrelia by real-time PCR followed by conventional PCR and sequencing to identify species present. A. persicus ticks were found to carry B. anserina in 3 of 40 (7.5%) A. persicus tick pools, whilst hard tick pools yielded 2 of 16 (12.5%) positive for B. theileri. Collectively, these borrelial species and their tick vectors are likely to have an important economic impact of particular relevance to subsistence farmers in Ethiopia.  相似文献   
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59.

Background

Supportive supervision is one of the interventions that fosters program improvement by way of imparting knowledge and skills to health workers. The basic challenge in supportive supervision is the availability of data in real time for timely and effective feedback. Thus, the main objective of this study was to determine the contribution of real-time data collection during supportive supervision for timely feedback and generation of evidence for health intervention planning.

Methods

We analyzed supportive supervision records collected through handheld devices employing the open data kit (ODK) platform from July 2015 to June 2016. Supervision was conducted across the country by 592 World Health Organization (WHO) officers. The availability of real-time data and the distance of health facilities to the community were analyzed.

Results

During the study period, 90,396 health facilities were supervised. The average time spent during supervision varied from 1.53 to 3.78 h across the six geopolitical zones of the country. The average interval between completion of the supervisory checklist and synchronization with the server varied from 3.9 h to 7.5 h. The average distance between the health facility and a ward varied from 5 to 24 km.

Conclusion

The use of handheld devices for supportive supervision provided real-time data from health facilities to state and zonal levels for analysis and feedback. Program officers used the findings to rectify process indicators in time for a better outcome.
  相似文献   
60.
The occurrence of eclampsia in an extra uterine pregnancy is a very rare entity. We report a case of a patient with eclampsia and advanced extra-uterine pregnancy. The fits were controlled with diazepam and the patient had laparotomy for the evacuation of the fetus from the abdominal cavity. She had an uneventful post operative recovery and was discharged home in good health after 10 days.  相似文献   
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