Novice Learner Experiences in Software Development: A Study of Freshman Undergraduates

This paper presents a study that is part of a larger research project aimed at addressing the gap in the provision of educational software development processes for freshman, novice undergraduate learners, to improve proficiency levels. With the aim of understanding how such learners problem solve in software development in the absence of a formal process, this case study examines the experiences and depth of learning acquired by a sample set of novice undergraduates. A novel adaption of the Kirkpatrick framework known as AKM-SOLO is used to frame the evaluation. The study finds that without the scaffolding of an appropriate structured development process tailored to novices, students are in danger of failing to engage with the problem solving skills necessary for software development, particularly the skill of designing solutions prior to coding. It also finds that this lack of engagement directly impacts their affective state on the course and continues to negatively impact their proficiency and affective state in the second year of their studies leading to just under half of students surveyed being unsure if they wish to pursue a career in software development when they graduate

Disparities and risks of sexually transmissible infections among men who have sex with men in China: a meta-analysis and data synthesis.

BACKGROUND: Sexually transmitted infections (STIs), including Hepatitis B and C virus, are emerging public health risks in China, especially among men who have sex with men (MSM). This study aims to assess the magnitude and risks of STIs among Chinese MSM. METHODS: Chinese and English peer-reviewed articles were searched in five electronic databases from January 2000 to February 2013. Pooled prevalence estimates for each STI infection were calculated using meta-analysis. Infection risks of STIs in MSM, HIV-positive MSM and male sex workers (MSW) were obtained. This review followed the PRISMA guidelines and was registered in PROSPERO. RESULTS: Eighty-eight articles (11 in English and 77 in Chinese) investigating 35,203 MSM in 28 provinces were included in this review. The prevalence levels of STIs among MSM were 6.3% (95% CI: 3.5-11.0%) for chlamydia, 1.5% (0.7-2.9%) for genital wart, 1.9% (1.3-2.7%) for gonorrhoea, 8.9% (7.8-10.2%) for hepatitis B (HBV), 1.2% (1.0-1.6%) for hepatitis C (HCV), 66.3% (57.4-74.1%) for human papillomavirus (HPV), 10.6% (6.2-17.6%) for herpes simplex virus (HSV-2) and 4.3% (3.2-5.8%) for Ureaplasma urealyticum. HIV-positive MSM have consistently higher odds of all these infections than the broader MSM population. As a subgroup of MSM, MSW were 2.5 (1.4-4.7), 5.7 (2.7-12.3), and 2.2 (1.4-3.7) times more likely to be infected with chlamydia, gonorrhoea and HCV than the broader MSM population, respectively. CONCLUSION: Prevalence levels of STIs among MSW were significantly higher than the broader MSM population. Co-infection of HIV and STIs were prevalent among Chinese MSM. Integration of HIV and STIs healthcare and surveillance systems is essential in providing effective HIV/STIs preventive measures and treatments. TRIAL REGISTRATION: PROSPERO NO: CRD42013003721

The clinical relevance of PCL index on the reconstruction of anterior cruciate ligament with hamstring tendon autograft

The posterior cruciate ligament index (PCL index) has been reported as a diagnostic and prognostic marker for anterior cruciate ligament (ACL) reconstruction. The clinical relevance of PCL index on the reconstruction of ACL with hamstring tendon autograft has not been described in the literature. The objective of this study is to evaluate the importance of the PCL index as a marker of anatomic reconstruction and of functional improvement of patients undergoing ACL reconstruction with HT autograft. Twenty-four patients were submitted to ACL reconstruction with HT autograft. The PCL index was assessed by magnetic resonance imaging before and after surgery. The functional evaluation was performed through the International Knee Documentation Committee (IKDC) Subjective Knee Evaluation Form© and Knee Society Knee Scoring System© (IKS). Patients presented a significant positive variation of the PCL index, IKDC and IKS scores. There is no significant correlation between PCL index variation and IKDC and IKS scores (p > 0.05). Unlike other studies reporting a relationship between the PCL index, control of rotational kinematics, and functional improvement in patients undergoing ACL reconstruction with bone-patellar tendon-bone autograft, this study does not demonstrate this association. There is evidence in this study to show that the PCL index may be used as an anatomic reconstructive marker of ACL but not to predict the clinical outcome in this type of reconstruction.(undefined

The M235T Polymorphism in the AGT Gene and CHD Risk: Evidence of a Hardy-Weinberg Equilibrium Violation and Publication Bias in a Meta-Analysis

BACKGROUND: The M235T polymorphism in the AGT gene has been related to an increased risk of hypertension. This finding may also suggest an increased risk of coronary heart disease (CHD). METHODOLOGY/PRINCIPAL FINDINGS: A case-cohort study was conducted in 1,732 unrelated middle-age women (210 CHD cases and 1,522 controls) from a prospective cohort of 15,236 initially healthy Dutch women. We applied a Cox proportional hazards model to study the association of the polymorphism with acute myocardial infarction (AMI) (n = 71) and CHD. In the case-cohort study, no increased risk for CHD was found under the additive genetic model (hazard ratio [HR] = 1.20; 95% confidence interval [CI], 0.86 to 1.68; P = 0.28). This result was not changed by adjustment (HR = 1.17; 95% CI, 0.83 to 1.64; P = 0.38) nor by using dominant, recessive and pairwise genetic models. Analyses for AMI risk under the additive genetic model also did not show any statistically significant association (crude HR = 1.14; 95% CI, 0.93 to 1.39; P = 0.20). To evaluate the association, a comprehensive systematic review and meta-analysis were undertaken of all studies published up to February 2007 (searched through PubMed/MEDLINE, Web of Science and EMBASE). The meta-analysis (38 studies with 13284 cases and 18722 controls) showed a per-allele odds ratio (OR) of 1.08 (95% CI, 1.01 to 1.15; P = 0.02). Moderate to large levels of heterogeneity were identified between studies. Hardy-Weinberg equilibrium (HWE) violation and the mean age of cases were statistically significant sources of the observed variation. In a stratum of non-HWE violation studies, there was no effect. An asymmetric funnel plot, the Egger's test (P = 0.066), and the Begg-Mazumdar test (P = 0.074) were all suggestive of the presence of publication bias. CONCLUSIONS/SIGNIFICANCE: The pooled OR of the present meta-analysis, including our own data, presented evidence that there is an increase in the risk of CHD conferred by the M235T variant of the AGT gene. However, the relevance of this weakly positive overall association remains uncertain because it may be due to various residual biases, including HWE-violation and publication biases

A meta-analysis of genome-wide data from five European isolates reveals an association of COL22A1, SYT1, and GABRR2 with serum creatinine level

<p>Abstract</p> <p>Background</p> <p>Serum creatinine (S_CR) is the most important biomarker for a quick and non-invasive assessment of kidney function in population-based surveys. A substantial proportion of the inter-individual variability in S_CRlevel is explicable by genetic factors.</p> <p>Methods</p> <p>We performed a meta-analysis of genome-wide association studies of S_CRundertaken in five population isolates ('discovery cohorts'), all of which are part of the European Special Population Network (EUROSPAN) project. Genes showing the strongest evidence for an association with S_CR(candidate loci) were replicated in two additional population-based samples ('replication cohorts').</p> <p>Results</p> <p>After the discovery meta-analysis, 29 loci were selected for replication. Association between S_CRlevel and polymorphisms in the collagen type XXII alpha 1 (<it>COL22A1</it>) gene, on chromosome 8, and in the synaptotagmin-1 (<it>SYT1</it>) gene, on chromosome 12, were successfully replicated in the replication cohorts (p value = 1.0 × 10^-6and 1.7 × 10^-4, respectively). Evidence of association was also found for polymorphisms in a locus including the gamma-aminobutyric acid receptor rho-2 (<it>GABRR2</it>) gene and the ubiquitin-conjugating enzyme E2-J1 (<it>UBE2J1</it>) gene (replication p value = 3.6 × 10^-3). Previously reported findings, associating glomerular filtration rate with SNPs in the uromodulin (<it>UMOD</it>) gene and in the schroom family member 3 (<it>SCHROOM3</it>) gene were also replicated.</p> <p>Conclusions</p> <p>While confirming earlier results, our study provides new insights in the understanding of the genetic basis of serum creatinine regulatory processes. In particular, the association with the genes <it>SYT1 </it>and <it>GABRR2 </it>corroborate previous findings that highlighted a possible role of the neurotransmitters GABA_Areceptors in the regulation of the glomerular basement membrane and a possible interaction between GABA_Areceptors and synaptotagmin-I at the podocyte level.</p

The changing global distribution and prevalence of canine transmissible venereal tumour.

BACKGROUND: The canine transmissible venereal tumour (CTVT) is a contagious cancer that is naturally transmitted between dogs by the allogeneic transfer of living cancer cells during coitus. CTVT first arose several thousand years ago and has been reported in dog populations worldwide; however, its precise distribution patterns and prevalence remain unclear. RESULTS: We analysed historical literature and obtained CTVT prevalence information from 645 veterinarians and animal health workers in 109 countries in order to estimate CTVT's former and current global distribution and prevalence. This analysis confirmed that CTVT is endemic in at least 90 countries worldwide across all inhabited continents. CTVT is estimated to be present at a prevalence of one percent or more in dogs in at least 13 countries in South and Central America as well as in at least 11 countries in Africa and 8 countries in Asia. In the United States and Australia, CTVT was reported to be endemic only in remote indigenous communities. Comparison of current and historical reports of CTVT indicated that its prevalence has declined in Northern Europe, possibly due to changes in dog control laws during the nineteenth and twentieth centuries. Analysis of factors influencing CTVT prevalence showed that presence of free-roaming dogs was associated with increased CTVT prevalence, while dog spaying and neutering were associated with reduced CTVT prevalence. Our analysis indicated no gender bias for CTVT and we found no evidence that animals with CTVT frequently harbour concurrent infectious diseases. Vincristine was widely reported to be the most effective therapy for CTVT. CONCLUSIONS: Our results provide a survey of the current global distribution of CTVT, confirming that CTVT is endemic in at least 90 countries worldwide. Additionally, our analysis highlights factors that continue to modify CTVT's prevalence around the world and implicates free-roaming dogs as a reservoir for the disease. Our analysis also documents the disappearance of the disease from the United Kingdom during the twentieth century, which appears to have been an unintentional result of the introduction of dog control policies.This is the author's accepted manuscript. The final version of this article has been published by BioMed Central: http://www.biomedcentral.com/1746-6148/10/168

Admixture Mapping of 15,280 African Americans Identifies Obesity Susceptibility Loci on Chromosomes 5 and X

The prevalence of obesity (body mass index (BMI) ≥30 kg/m2) is higher in African Americans than in European Americans, even after adjustment for socioeconomic factors, suggesting that genetic factors may explain some of the difference. To identify genetic loci influencing BMI, we carried out a pooled analysis of genome-wide admixture mapping scans in 15,280 African Americans from 14 epidemiologic studies. Samples were genotyped at a median of 1,411 ancestry-informative markers. After adjusting for age, sex, and study, BMI was analyzed both as a dichotomized (top 20% versus bottom 20%) and a continuous trait. We found that a higher percentage of European ancestry was significantly correlated with lower BMI (ρ = −0.042, P = 1.6×10−7). In the dichotomized analysis, we detected two loci on chromosome X as associated with increased African ancestry: the first at Xq25 (locus-specific LOD = 5.94; genome-wide score = 3.22; case-control Z = −3.94); and the second at Xq13.1 (locus-specific LOD = 2.22; case-control Z = −4.62). Quantitative analysis identified a third locus at 5q13.3 where higher BMI was highly significantly associated with greater European ancestry (locus-specific LOD = 6.27; genome-wide score = 3.46). Further mapping studies with dense sets of markers will be necessary to identify the alleles in these regions of chromosomes X and 5 that may be associated with variation in BMI

The Cholesterol Metabolite 25-Hydroxycholesterol Activates Estrogen Receptor α-Mediated Signaling in Cancer Cells and in Cardiomyocytes

The hydroxylated derivatives of cholesterol, such as the oxysterols, play important roles in lipid metabolism. In particular, 25-hydroxycholesterol (25 HC) has been implicated in a variety of metabolic events including cholesterol homeostasis and atherosclerosis. 25 HC is detectable in human plasma after ingestion of a meal rich in oxysterols and following a dietary cholesterol challenge. In addition, the levels of oxysterols, including 25 HC, have been found to be elevated in hypercholesterolemic serum.Here, we demonstrate that the estrogen receptor (ER) α mediates gene expression changes and growth responses induced by 25 HC in breast and ovarian cancer cells. Moreover, 25 HC exhibits the ERα-dependent ability like 17 β-estradiol (E2) to inhibit the up-regulation of HIF-1α and connective tissue growth factor by hypoxic conditions in cardiomyocytes and rat heart preparations and to prevent the hypoxia-induced apoptosis.The estrogen action exerted by 25 HC may be considered as an additional factor involved in the progression of breast and ovarian tumors. Moreover, the estrogen-like activity of 25 HC elicited in the cardiovascular system may play a role against hypoxic environments