458 research outputs found
Ghera: A Repository of Android App Vulnerability Benchmarks
Security of mobile apps affects the security of their users. This has fueled
the development of techniques to automatically detect vulnerabilities in mobile
apps and help developers secure their apps; specifically, in the context of
Android platform due to openness and ubiquitousness of the platform. Despite a
slew of research efforts in this space, there is no comprehensive repository of
up-to-date and lean benchmarks that contain most of the known Android app
vulnerabilities and, consequently, can be used to rigorously evaluate both
existing and new vulnerability detection techniques and help developers learn
about Android app vulnerabilities. In this paper, we describe Ghera, an open
source repository of benchmarks that capture 25 known vulnerabilities in
Android apps (as pairs of exploited/benign and exploiting/malicious apps). We
also present desirable characteristics of vulnerability benchmarks and
repositories that we uncovered while creating Ghera.Comment: 10 pages. Accepted at PROMISE'1
Annular pancreas: endoscopic and pancreatographic findings from a tertiary referral ERCP center
Background and Aims
Annular pancreas is a congenital anomaly whereby pancreatic tissue encircles the duodenum. Current knowledge of endoscopic findings of annular pancreas is limited to small case series. The aim of this study was to describe the endoscopic and pancreatographic findings of patients with annular pancreas at a large tertiary care ERCP center.
Methods
This is a retrospective observational study. Our Institutional Review Board–approved, prospectively collected ERCP database was queried for cases of annular pancreas. The electronic medical records were searched for patient and procedure-related data.
Results
From January 1, 1994, to December 31, 2016, 46 patients with annular pancreas underwent ERCP at our institution. Index ERCP was technically successful in 42 patients (91.3%), and technical success was achieved in all 46 patients (100%) after 2 attempts, when required. A duodenal narrowing or ring was found in most patients (n = 39, 84.8%), yet only 2 (4.3%) had retained gastric contents. Pancreas divisum was found in 21 patients (45.7%), 18 of which were complete divisum. Pancreatobiliary neoplasia was the indication for ERCP in 7 patients (15.2%). Pancreatographic findings consistent with chronic pancreatitis were noted in 15 patients (32.6%) at the index ERCP.
Conclusion
This is the largest series describing the endoscopic and pancreatographic findings of patients with annular pancreas. We found that 45.7% of patients had concurrent pancreas divisum. Endoscopic therapy was successful in most patients at our institution after 1 ERCP, and in all patients after a second ERCP. Nearly one-third of patients had findings consistent with chronic pancreatitis at the time of index ERCP. It is unclear whether this may be a feature of the natural history of annular pancreas
A 3D pancreatic tumor model to study T cell infiltration.
Human T cell infiltration across the endothelium in a 3-dimensional pancreatic tumor model in relation to activation and cellular components
The past, current and future epidemiological dynamic of SARS-CoV-2
SARS-CoV-2, the agent of the COVID-19 pandemic, emerged in late 2019 in China, and rapidly spread throughout the world to reach all continents. As the virus expanded in its novel human host, viral lineages diversified through the accumulation of around two mutations a month on average. Different viral lineages have replaced each other since the start of the pandemic, with the most successful Alpha, Delta and Omicron variants of concern (VoCs) sequentially sweeping through the world to reach high global prevalence. Neither Alpha nor Delta was characterized by strong immune escape, with their success coming mainly from their higher transmissibility. Omicron is far more prone to immune evasion and spread primarily due to its increased ability to (re-)infect hosts with prior immunity. As host immunity reaches high levels globally through vaccination and prior infection, the epidemic is expected to transition from a pandemic regime to an endemic one where seasonality and waning host immunization are anticipated to become the primary forces shaping future SARS-CoV-2 lineage dynamics. In this review, we consider a body of evidence on the origins, host tropism, epidemiology, genomic and immunogenetic evolution of SARS-CoV-2 including an assessment of other coronaviruses infecting humans. Considering what is known so far, we conclude by delineating scenarios for the future dynamic of SARS-CoV-2, ranging from the good—circulation of a fifth endemic ‘common cold’ coronavirus of potentially low virulence, the bad—a situation roughly comparable with seasonal flu, and the ugly—extensive diversification into serotypes with long-term high-level endemicity
Characterization of the Mutagenic Spectrum of 4-Nitroquinoline 1-Oxide (4-NQO) in Aspergillus nidulans by Whole Genome Sequencing
4-Nitroquinoline 1-oxide (4-NQO) is a highly carcinogenic chemical that induces mutations in bacteria, fungi, and animals through the formation of bulky purine adducts. 4-NQO has been used as a mutagen for genetic screens and in both the study of DNA damage and DNA repair. In the model eukaryote Aspergillus nidulans, 4-NQO−based genetic screens have been used to study diverse processes, including gene regulation, mitosis, metabolism, organelle transport, and septation. Early work during the 1970s using bacterial and yeast mutation tester strains concluded that 4-NQO was a guanine-specific mutagen. However, these strains were limited in their ability to determine full mutagenic potential, as they could not identify mutations at multiple sites, unlinked suppressor mutations, or G:C to C:G transversions. We have now used a whole genome resequencing approach with mutant strains generated from two independent genetic screens to determine the full mutagenic spectrum of 4-NQO in A. nidulans. Analysis of 3994 mutations from 38 mutant strains reveals that 4-NQO induces substitutions in both guanine and adenine residues, although with a 19-fold preference for guanine. We found no association between mutation load and mutagen dose and observed no sequence bias in the residues flanking the mutated purine base. The mutations were distributed randomly throughout most of the genome. Our data provide new evidence that 4-NQO can potentially target all base pairs. Furthermore, we predict that current practices for 4-NQO−induced mutagenesis are sufficient to reach gene saturation for genetic screens with feasible identification of causative mutations via whole genome resequencing
The student perspective in developing graduate attributes through problem-based learning in first year agricultural science
To meet university proclamations, academic staff are required to include graduate attributes in student learning. The approach adopted in this first year agricultural science course was to utilise problem-based learning to develop discipline knowledge and graduate attributes in a seamless manner. Rather than giving the students a questionnaire with options for students to indicate what graduate attribute they had learned, a structured learning journal was used to question students about their learning without specifically asking about any graduate attributes. Analysis of the learning journals revealed that significant numbers of students perceived that they had learned or practiced a range of graduate attributes, including teamwork, research, social responsibility, personal attributes, writing abilities, time management, problem solving, leadership, and multidisciplinary skills. These student perceptions exceeded the teachers’ expectations and revealed that problem-based learning in teams can be used for learning discipline knowledge and developing graduate attributes
FIRST YEAR AGRICULTURAL SCIENCE STUDENT PERSPECTIVES IN GRADUATE ATTRIBUTE DEVELOPMENT THROUGH PROBLEM-BASED LEARNING
Academic staff are required to include graduate attributes like inquiry and problem-solving in student learning to meet university proclamations. In response to student evaluations that a traditional lecture-based first year agriculture science course was not effective in motivating students, a new course introduced inquiry orientated learning primarily to motivate and engage students, to promote deep learning and problem-solving skills. The approach adopted problem-based learning to develop discipline knowledge and graduate attributes in a seamless manner. Instead of giving the students a questionnaire with options for students to indicate what graduate attribute they had learned, a structured learning journal was used to question students about their learning without specifically asking about any graduate attributes. Analysis of the learning journals revealed that significant numbers of students perceived that they had learned or practiced a range of graduate attributes, including teamwork, research, personal attributes, writing abilities, time management, problem solving, leadership, and multidisciplinary skills. The students had learned and practiced these graduate attributes while engaging in authentic problem-solving activities as groups in online and face-to-face environments. These student perceptions exceeded the teachers’ expectations and revealed that problem-based learning in teams can be used for learning discipline knowledge and developing graduate attributes
Endoscopic papillectomy: risk factors for incomplete resection and recurrence during long-term follow-up
Background
Endoscopic papillectomy is increasingly used as an alternative to surgery for ampullary adenomas and other noninvasive ampullary lesions.
Objective
To measure short-term safety and efficacy of endoscopic papillectomy, define patient and lesion characteristics associated with incomplete endoscopic resection, and measure adenoma recurrence rates during long-term follow-up.
Design
Retrospective cohort study.
Setting
Tertiary-care academic medical center.
Patients
All patients who underwent endoscopic papillectomy for ampullary lesions between July 1995 and June 2012.
Intervention
Endoscopic papillectomy.
Main Outcome Measurements
Patient and lesion characteristics associated with incomplete endoscopic resection and ampullary adenoma-free survival analysis.
Results
We identified 182 patients who underwent endoscopic papillectomy, 134 (73.6%) having complete resection. Short-term adverse events occurred in 34 (18.7%). Risk factors for incomplete resection were jaundice at presentation (odds ratio [OR] 0.21, 95% confidence interval [CI] 0.07–0.69; P = .009), occult adenocarcinoma (OR 0.06, 95% CI, 0.01–0.36; P = .002), and intraductal involvement (OR 0.29, 95% CI, 0.11–0.75; P = .011). The en bloc resection technique was strongly associated with a higher rate of complete resection (OR 4.05, 95% CI, 1.71–9.59; P = .001). Among patients with ampullary adenoma who had complete resection (n = 107), 16 patients (15%) developed recurrence up to 65 months after resection.
Limitations
Retrospective analysis.
Conclusion
Jaundice at presentation, occult adenocarcinoma in the resected specimen, and intraductal involvement are associated with a lower rate of complete resection, whereas en bloc papillectomy increases the odds of complete endoscopic resection. Despite complete resection, recurrence was observed up to 5 years after papillectomy, confirming the need for long-term surveillance
- …