Computer visual syndrome in university students in times of pandemic.

INTRODUCTION: One of the consequences of prolonged use of bright screens such as those of the computer or cell phone, is the computer visual syndrome where characteristic symptoms are presented that normally disappear after a couple of hours when you stop using electronic devices. The prevalence is high due to multiple risk factors. OBJECTIVE: To determine the prevalence of computer vision syndrome in medical students at the University of Boyacá in times of pandemic. METHODOLOGY: Descriptive and cross-sectional observational study. The study population were medical students, the data were collected in September and October of the year, an electronic survey was carried out for data collection. RESULTS: A total of 300 participants were invited to participate in the study. 78% (234) of participating students suffer from SVI. 67.09% (157) of the participants who reported suffering from SVI were female and 32.91% (77) were male. CONCLUSIONS: Computer visual syndrome is very common among medical students at the University of Boyacá. This study has shown that the presence of SVI has been significantly associated with exposure factors that were triggered during the pandemic period, where frequent virtual classes and long hours led to high exposure to screens. In addition, in the era of virtuality, communication through social networks increased the use of cell phones, which increases the possibility of the appearance of this syndrome.

Experimental infection of conventional newly-weaned piglets with porcine astrovirus.

The presence of porcine astroviruses in diarrheic and healthy pigs has been reported, however, the consequences of the astrovirus infection during the weaning process have not been described. In this study, eight healthy conventional newly-weaned piglets were used to evaluate effects of astrovirus infection during the first five days. Four piglets were infected with the porcine astrovirus PoAstV/PUJP5 strain and the other four represented the control group. Body weight, rectal temperature, diarrhea and other clinical signs were monitored every 24 hours. The results showed that all animals gained body weight, the occurrence of mild diarrhea on the 3rd day post-infection, and the astroviral presence in diarrheic samples. On the 5th day post-infection all the piglets were euthanized and then intestinal and extra-intestinal tissues were analyzed for the presence of PoAstV/PUJP5. The cytoplasmic antigen of PoAstV/PUJP5 was observed in the enterocytes of infected piglets from jejunum, ileum, colon and in inflammatory cells from mesenteric lymph nodes. In addition, villi atrophy, fusion, epithelial hyperplasia and incipient virus detection in mesenteric lymph were observed. RNAemia could not be proved. This study shows for the first time the effects of porcine astrovirus infection on conventional newly-weaning piglets. Keywords: porcine astrovirus; newly-weaned piglets.

Differential evolution of cerebral and cerebellar fossae in recent Homo: A new methodological approach.

The endocranium shows the influence of the shape and development of brain tissues and overall brain modifications. During the late Upper Pleistocene and Holocene smaller brains appeared and the higher position of endinion relative to inion might indicate changes in cerebellar and occipital lobes. In previous studies, the depths of the cerebral and cerebellar fossae were not specifically considered; new tools for quantitatively measuring these irregular, problematic curved areas need to be developed. This paper's main objective is to investigate to what degree changes in the fossae's depths of extant humans have occurred with respect to fossil anatomically modern humans (AMH) and older Homo species. The proportions of the occipital and nuchal planes are compared measuring the inner and outer surfaces of the bone. Additionally, this paper proposes a quantitative geometric methodology based on endocranial landmarks that create a plane with which to measure the position of the deepest part of the fossa: it represents a curvature maxima - concavity - associated with local structures. The four points thus obtained could be framed in Bookstein's Type II landmarks but without biomechanical implication. Through univariate, bivariate and multivariate analyses (principal components analysis) of raw and size-corrected data we study the differential evolution in recent Homo species, which presents a more vertical occipital area than ancient fossils. Our results corroborate this derived trait; additionally, we have observed a tendency towards a relative decrease in the depth of the cerebral fossae and maintenance of the cerebellar fossae.

Phylogenetic analysis of classical swine fever virus (CSFV) field isolates from outbreaks in South and Central America.

To date, there is little information concerning the epidemiological situation of classical swine fever (CSF) in the Americas. Besides summarizing the available data, genotyping of isolates from outbreaks in domestic pigs in several countries of South and Central America was performed. For this, a 190 base fragment of the E2 envelope glycoprotein gene was used. European strains and isolates, and historical isolates from the United States (US) were included for comparison. In contrast to the situation in most parts of Europe, where group 2 isolates predominate, it was found that all the isolates from the American continent analyzed belonged to group 1 and were further resolved into three subgroups. The Cuban isolates clustered in subgroup 1.2, whereas the isolates from Honduras and Guatemala clustered in subgroup 1.3. The remaining isolates from Argentina, Brazil, Colombia and Mexico generated four poorly resolved clusters in subgroup 1.1, together with the vaccine strains, with historical European and US isolates, and with a recent Russian isolate. While the vaccine strains and the historical European isolates formed a relatively distinct cluster, one of the US isolates clustered together with the Mexican, and another one with Colombian isolates. Historically, CSF (hog cholera) was observed almost simultaneously in the US and in Europe in the first half of the 19th century, and its origin remains a matter of discussion. Our results showed that the US isolates are closely related to isolates from South America, while appearance of isolates in Cuba on one hand and in Honduras and Guatemala on the other hand, seems to have been due to unrelated events. This allows to speculate that at least in the American continent, CSF virus may have appeared independently in several regions, and spreading may have been a secondary effect.