Cluster analysis in Higher Education Institutions' knowledge identification and production processes

The objective of this study is to describe the processes of identification and creation of knowledge in higher education institutions (HEI). The sample is composed of 7 universities in the city of Barranquila in Colombia, and is non-probabilistic. For this purpose, a survey was used to collect data from the directors and vice-rectors of research of the research departments. For its part, the research methodology is framed in the tools of cluster analysis and principal component analysis. The established approach made it possible to demonstrate that universities have two characteristics for identifying and creating knowledge in HEIs: community learning and individual learning. © 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the Conference Program Chairs

Impact of implant thread design on insertion torque and osseointegration:a preclinical model

Successful osseointegration of endosteal dental implants has been attributed to implant design, including the macro-, micro- and nano- geometric properties. Based on current literature pertaining to implant design, the resultant cellular and bone healing response is unknown when the thread thickness of the implants is increased, resulting in an increased contact area in implants designed with healing chambers. The aim of this study was to evaluate the effect of two implant designs with different thread profiles on the osseointegration parameters and implant stability at 3- and 6-weeks in vivo using a well-established preclinical dog model. A total of 48 type V Ti alloy implants were divided in two groups according to their thread design (D1= +0.1x/mm and D2= +0.15x/mm) and placed in an interpolated fashion into the radii of six beagles. Insertion torque was measured at time of placement, radii were extracted for histological processing following 3- and 6-week healing intervals. Histologic and histomorphometric analyses were performed in terms of bone to implant contact (%BIC) and bone area fraction occupancy within implant threads (%BAFO). Statistical analyses were performed through a linear mixed model with fixed factors of time and implant thread design. Surface roughness analysis demonstrated no significant differences in Sa and Sq between D1 and D2 implant designs, which confirmed that both implant designs were homogenous except for their respective thread profiles. For insertion torque, statistically significant lower values were recorded for D1 in comparison to D2 (59.6 ± 11.1 and 78.9 ± 10.1 N?cm, respectively). Furthermore, there were no significant differences with respect to histological analysis and histomorphometric parameters, between D1 and D2 at both time points. Both thread profiles presented equivalent potential to successfully osseointegrate in the osteotomies, with D2 yielding higher mechanical retention upon placement without detrimental bone resorption

SARS-CoV-2 susceptibility and COVID-19 disease severity are associated with genetic variants affecting gene expression in a variety of tissues

Variability in SARS-CoV-2 susceptibility and COVID-19 disease severity between individuals is partly due to genetic factors. Here, we identify 4 genomic loci with suggestive associations for SARS-CoV-2 susceptibility and 19 for COVID-19 disease severity. Four of these 23 loci likely have an ethnicity-specific component. Genome-wide association study (GWAS) signals in 11 loci colocalize with expression quantitative trait loci (eQTLs) associated with the expression of 20 genes in 62 tissues/cell types (range: 1:43 tissues/gene), including lung, brain, heart, muscle, and skin as well as the digestive system and immune system. We perform genetic fine mapping to compute 99% credible SNP sets, which identify 10 GWAS loci that have eight or fewer SNPs in the credible set, including three loci with one single likely causal SNP. Our study suggests that the diverse symptoms and disease severity of COVID-19 observed between individuals is associated with variants across the genome, affecting gene expression levels in a wide variety of tissue types

Key factors influencing outcome of peroxide-based bleaching treatments in dentistry

Thesis (M.A.)--Boston University PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at [email protected]. Thank you.The efficacy and safety of peroxide-based teeth whitening has been a largely contested issue over the last two decades. Several reviews have been written on the subject, but the current literature lacks a more involved description of the key factors that influence whitening effects and the manifestation of its adverse effects. Thus, a review of these key factors should be able to more clearly define how these influence treatment outcome during peroxide-based teeth whitening treatments, and how these treatments are likely to expose individuals to additional risk factors. Based on evidence in the current literature, whitening efficacies are dependent on a series of variables associated with treatment. Of these variables, the ones more directly associated with the whitening effects produced after treatment are peroxide concentration, active bleaching time, and--to some extent--the choice between currently available delivery systems (trays, strips, application brushes). From the studies reviewed, higher concentrations of peroxide produce more pronounced whitening effects, while lower concentrations needing longer active bleaching times to produce similar color changes, as measured by either VITA shade guides, or the CIEL*a*b* system. Color relegations are likely to occur with treatments composed of lower number of treatment sessions compared to treatments with multiple sessions. In terms of adverse effects, peroxides have been found to potentially be associated with carcinogenicity and cytotoxicity not only in oral tissues but in the gastrointestinal lining of hamsters and rats during in vivo studies. However, current reviews and studies have highlighted that excessive levels of peroxide exposure are needed to promote tumor growth or induce cytotoxic effects in the oral cavity; thus, it is unlikely that teeth whitening use of peroxides exposes individuals to dangerous levels of carcinogenicity and cytotoxicity. Nevertheless, some studies have found a decrease in odontoblast viability at concentrations of 16% carbamide peroxide, suggesting cytotoxicity may become a more significant factor at carbamide peroxide concentrations higher than 16%. Tooth and gingival sensitivity was closely associated with the use of either higher peroxide concentrations or longer active bleaching times. However, desensitizing agents such as fluoride, potassium nitrate, and amorphous calcium-phosphate have been found to effectively reduce this sensitivity of teeth and gingival tissues in people experiencing tissue sensitivity. Structural damage to enamel and dentin were found to be statistically insignificant in the studies reviewed, with whitening products of low acidity causing the bulk of the observed demineralization in in vitro studies. In vivo studies evaluating peroxide-associated demineralization have suggested that salivary components are capable of fully remineralizing any affected teeth structures following peroxide-based teeth whitening. In conclusion, from the studies analyzed, it is advisable to use concentrations lower than 16% carbamide peroxide during at-home treatments. However, use of higher concentrations are acceptable if provided under professional supervision. People with gingival recessions are more likely to experience sensitivity, so use of desensitizing agents at the time of treatment is advisable. In terms of whitening pastes, whitening gels of relatively neutral pH should be used (pH between 5 and 7) to reduce enamel and dentin demineralization; additives may include desensitizing agents to help with sensitivity and antioxidants which can counteract the oxidative stress of peroxides on oral tissues

Guías de laboratorio de calor y ondas

El compendio de guías de laboratorio de calor y ondas incluye prácticas que les permiten a los estudiantes fortalecer habilidades al aplicar conceptos de la asignatura en un ambiente de laboratorio. Esta guía articula experiencias fundamentales que incluyen normativa de seguridad aplicable, recursos a utilizar, procedimientos, cálculos y un cuestionario de análisis. Con ello, los estudiantes podrán consolidar los conocimientos teórico-prácticos al aplicar conceptos de las temáticas de la asignatura calor y ondas.Densidad de Sólidos y Líquidos 7 -- Introducción 7 -- Objetivo 10 -- Normativa de Seguridad 10 -- Recursos 10 -- Procedimiento Experimentales 11 -- Cálculos 12 -- Cuestionario 12 -- Referencias 13 -- Pre- Informe 14 -- Principio de Arquímedes 17 -- Introducción 17 -- Objetivo 18 -- Normativa de Seguridad 18 -- Recursos 18 -- Procedimiento Experimentales 19 -- Cálculos 20 -- Referencias 20 -- Pre- Informe 22 -- Dilatación Térmica 25 -- Introducción 25 -- Objetivo 26 -- Normativa de Seguridad 26 -- Recursos 26 -- Procedimiento Experimentales 26 -- Cálculos 28 -- Cuestionario 28 -- Referencias 28 -- Pre- Informe 29 -- Equilibrio Térmico 32 -- Introducción 32 -- Objetivo 32 -- Normativa de Seguridad 32 -- Recursos 33 -- Procedimiento Experimentales 33 -- Cálculos 35 -- Cuestionario 36 -- Referencias 37 -- Calor Especifico de un Sólido 41 -- Introducción 41 -- Objetivo 42 -- Normativa de Seguridad 42 -- Recursos 42 -- Procedimiento Experimentales 43 -- Cálculos 44 -- Cuestionario 45 -- Referencias 45 -- Cambio de Fase 49 -- Introducción 49 -- Objetivo 50 -- Normativa de Seguridad 50 -- Recursos 50 -- Procedimiento Experimentales 50 -- Cálculos 51 -- Cuestionario 52 -- Referencias 53 -- Pre- Informe 54 -- Sistema Masa Resorte 57 -- Introducción 58 -- Objetivo 58 -- Normativa de Seguridad 58 -- Recursos 59 -- Procedimiento Experimentales 59 -- Cuestionario y cálculos 60 -- Referencias 61 -- Pre- Informe 62 -- Péndulo Simple 65 -- Introducción 65 -- Objetivo 68 -- Normativa de Seguridad 68 -- Recursos 68 -- Procedimiento Experimentales 69 -- Cálculos 71 -- Cuestionario 72 -- Péndulo Físico 74 -- Aspectos conceptuales 74 -- Objetivo 76 -- Equipo 76 -- Procedimiento Experimentales 77 -- Cálculos 78 -- Cuestionario 79 -- Referencias 79 -- Ondas Estacionarias en una Cuerda 81 -- Introducción 81 -- Objetivo 84 -- Normativa de Seguridad 84 -- Recursos 84 -- Procedimiento Experimentales 85 -- Cálculos 86 -- Cuestionario 87 -- Referencias 88 -- Tubos Sonoros 89 -- Introducción 89 -- Objetivo 89 -- Normativa de Seguridad 90 -- Recursos 90 -- Procedimiento Experimentales 90 -- Cálculos 92 -- Cuestionario 92 -- Referencias 93 -- Formato para Informe 9

Guías de laboratorio de ondas y óptica

El compendio de guías de laboratorio de física ondas y óptica incluye prácticas que les permiten a los estudiantes fortalecer habilidades al aplicar conceptos de la asignatura en un ambiente de laboratorio. Esta guía articula experiencias fundamentales que incluyen normativa de seguridad aplicable, recursos a utilizar, procedimientos, cálculos y un cuestionario de análisis. Con ello, los estudiantes podrán consolidar los conocimientos teórico-prácticos al aplicar conceptos de las temáticas de la asignatura física ondas y óptica.Densidad de Sólidos y Líquidos 7 -- Introducción 7 -- Objetivos 10 -- Normativa de Seguridad 10 -- Recursos 10 -- Procedimiento Experimentales 11 -- Cálculos 12 -- Cuestionario 12 -- Referencias 13 -- Pre- Informe 14 -- Principio de Arquímedes 17 -- Introducción 17 -- Objetivos 18 -- Normativa de Seguridad 18 -- Recursos 18 -- Procedimiento Experimentales 19 -- Cálculos 20 -- Cuestionario 20 -- Referencias 22 -- Pre- Informe 25 -- Dilatación Térmica 25 -- Introducción 25 -- Objetivos 26 -- Normativa de Seguridad 26 -- Recursos 26 -- Procedimiento Experimentales 26 -- Cálculos 28 -- Cuestionario 28 -- Referencias 28 -- Pre- Informe 29 -- Equilibrio Térmico 32 -- Introducción 32 -- Objetivos 32 -- Normativa de Seguridad 32 -- Recursos 33 -- Procedimiento Experimentales 33 -- Cálculos 35 -- Cuestionario 36 -- Referencias 37 -- Calor Especifico de un Sólido 41 -- Introducción 41 -- Objetivos 42 -- Normativa de Seguridad 42 -- Recursos 42 -- Procedimiento Experimentales 43 -- Cálculos 44 -- Cuestionario 45 -- Referencias 45 -- Cambio de Fase 49 -- Introducción 49 -- Objetivos 50 -- Normativa de Seguridad 50 -- Recursos 50 -- Procedimiento Experimentales 50 -- Cálculos 51 -- Cuestionario 52 -- Referencias 53 -- Pre- Informe 54 -- Sistema Masa Resorte 57 -- Introducción 58 -- Objetivos 58 -- Normativa de Seguridad 58 -- Recursos 59 -- Procedimiento Experimentales 59 – Cuestionario y cálculos 60 -- Referencias 61 -- Pre- Informe 62 -- Péndulo Simple 65 -- Introducción 65 -- Objetivos 68 -- Normativa de Seguridad 68 -- Recursos 68 -- Procedimiento Experimentales 69 -- Cálculos 71 -- Cuestionario 72 -- Péndulo Físico 74 -- Introducción 74 -- Objetivos 76 – Equipo 76 -- Procedimiento Experimentales 77 -- Cálculos 78 -- Cuestionario 79 -- Referencias 79 -- Ondas Estacionarias en una Cuerda 81 -- Introducción 81 -- Objetivos 84 -- Normativa de Seguridad 84 -- Recursos 84 -- Procedimiento Experimentales 85 -- Cálculos 86 -- Cuestionario 87 -- Referencias 88 -- Tubos Sonoros 89 -- Introducción 89 -- Objetivos 89 -- Normativa de Seguridad 90 -- Recursos 90 -- Procedimiento Experimentales 90 -- Cálculos 92 -- Cuestionario 92 -- Referencias 93 -- Formato para Informe 9

International Nosocomial Infection Control Consortiu (INICC) report, data summary of 43 countries for 2007-2012. Device-associated module

We report the results of an International Nosocomial Infection Control Consortium (INICC) surveillance study from January 2007-December 2012 in 503 intensive care units (ICUs) in Latin America, Asia, Africa, and Europe. During the 6-year study using the Centers for Disease Control and Prevention's (CDC) U.S. National Healthcare Safety Network (NHSN) definitions for device-associated health care–associated infection (DA-HAI), we collected prospective data from 605,310 patients hospitalized in the INICC's ICUs for an aggregate of 3,338,396 days. Although device utilization in the INICC's ICUs was similar to that reported from ICUs in the U.S. in the CDC's NHSN, rates of device-associated nosocomial infection were higher in the ICUs of the INICC hospitals: the pooled rate of central line–associated bloodstream infection in the INICC's ICUs, 4.9 per 1,000 central line days, is nearly 5-fold higher than the 0.9 per 1,000 central line days reported from comparable U.S. ICUs. The overall rate of ventilator-associated pneumonia was also higher (16.8 vs 1.1 per 1,000 ventilator days) as was the rate of catheter-associated urinary tract infection (5.5 vs 1.3 per 1,000 catheter days). Frequencies of resistance of Pseudomonas isolates to amikacin (42.8% vs 10%) and imipenem (42.4% vs 26.1%) and Klebsiella pneumoniae isolates to ceftazidime (71.2% vs 28.8%) and imipenem (19.6% vs 12.8%) were also higher in the INICC's ICUs compared with the ICUs of the CDC's NHSN

COVID-19 Host Genetics Initiative. A first update on mapping the human genetic architecture of COVID-19

The COVID-19 pandemic continues to pose a major public health threat, especially in countries with low vaccination rates. To better understand the biological underpinnings of SARS-CoV-2 infection and COVID-19 severity, we formed the COVID-19 Host Genetics Initiative1. Here we present a genome-wide association study meta-analysis of up to 125,584 cases and over 2.5 million control individuals across 60 studies from 25 countries, adding 11 genome-wide significant loci compared with those previously identified2. Genes at new loci, including SFTPD, MUC5B and ACE2, reveal compelling insights regarding disease susceptibility and severity.</p