Catalogue Search | MBRL
Are you sure you want to remove the book from the shelf?
{{itemTitle}}
12,316
result(s) for
"González, Fernando"
Sort by:
A novel computational workflow to holistically assess total knee arthroplasty biomechanics identifies subject-specific effects of joint mechanics on implant fixation
Computational studies of total knee arthroplasty (TKA) often focus on either joint mechanics (kinematics and forces) or implant fixation mechanics. However, such disconnect between joint and fixation mechanics hinders our understanding of overall TKA biomechanical function by preventing identification of key relationships between these two levels of TKA mechanics. We developed a computational workflow to holistically assess TKA biomechanics by integrating musculoskeletal and finite element (FE) models. For our initial study using the workflow, we investigated how tibiofemoral contact mechanics affected the risk of failure due to debonding at the implant-cement interface using the four available subjects from the Grand Challenge Competitions to Predict In Vivo Knee Loads. We used a musculoskeletal model with a 12 degrees-of-freedom knee joint to simulate the stance phase of gait for each subject. The computed tibiofemoral joint forces at each node in contact were direct inputs to FE simulations of the same subjects. We found that the peak risk of failure did not coincide with the peak joint forces or the extreme tibiofemoral contact positions. Moreover, despite the consistency of joint forces across subjects, we observed important variability in the profile of the risk of failure during gait. Thus, by a combined evaluation of the joint and implant fixation mechanics of TKA, we could identify subject-specific effects of joint kinematics and forces on implant fixation that would otherwise have gone unnoticed. We intend to apply our workflow to evaluate the impact of implant alignment and design on TKA biomechanics.
Journal Article
One is not enough: On the effects of reference genome for the mapping and subsequent analyses of short-reads
Mapping of high-throughput sequencing (HTS) reads to a single arbitrary reference genome is a frequently used approach in microbial genomics. However, the choice of a reference may represent a source of errors that may affect subsequent analyses such as the detection of single nucleotide polymorphisms (SNPs) and phylogenetic inference. In this work, we evaluated the effect of reference choice on short-read sequence data from five clinically and epidemiologically relevant bacteria ( Klebsiella pneumoniae , Legionella pneumophila , Neisseria gonorrhoeae , Pseudomonas aeruginosa and Serratia marcescens ). Publicly available whole-genome assemblies encompassing the genomic diversity of these species were selected as reference sequences, and read alignment statistics, SNP calling, recombination rates, d N /d S ratios, and phylogenetic trees were evaluated depending on the mapping reference. The choice of different reference genomes proved to have an impact on almost all the parameters considered in the five species. In addition, these biases had potential epidemiological implications such as including/excluding isolates of particular clades and the estimation of genetic distances. These findings suggest that the single reference approach might introduce systematic errors during mapping that affect subsequent analyses, particularly for data sets with isolates from genetically diverse backgrounds. In any case, exploring the effects of different references on the final conclusions is highly recommended.
Journal Article
Challenges for Innovation and Sustainable Development in Latin America: The Significance of Institutions and Human Capital
Sustainable development is considered as one of the vital challenges of the 21st century for humanity. The COVID-19 pandemic has disrupted economic and social life, forcing governments and businesses to reconsider their priorities. There are rare empirical studies on the national innovation system and its relationship to sustainability development for emerging countries. This paper aims at shedding light on how mission-oriented policies have marked sustainable regional development and innovation in Latin America. The present study presents the capabilities that could support the improvement of the national innovation system and, as a consequence, sustainability development. To understand how Latin American countries act on innovation and sustainable development initiatives, two global rankings in these areas, The Global Innovation Index 2020 and The Sustainable Development Report 2020, were analyzed. The results indicate some obstacles must be overcome such as the high levels of social inequality and poverty that still constitute significant challenges for this region. Today’s biggest challenges are facing a pandemic situation and guaranteeing economic development that allows the underprivileged to escape poverty without dooming future generations to an even more degraded environment than the current one. Innovation continues to play a critical role in the transition toward a more sustainable world.
Journal Article
Fully differential soft gluon evolution at the amplitude level
A
bstract
We study differential intra-jet radiation patterns in jet production at full colour. We present a systematic study of several QCD 2 → 2 processes and also multi-jet production from a colourless initial state. We examine how subleading colour corrections are distributed differentially in phase space and find that mere normalization effects due to subleading colour can be due to subtle cancellations across phase space. In general, we find that subleading colour does affect the shapes of distributions.
Journal Article
Diversity of culturable bacteria of freshwater environments from an altitudinal gradient in the eastern Cordillera of Colombia
Abstract
Bacteria are an essential biotic component in freshwater environments. A group of 262 bacterial strains of freshwater environments from an altitudinal gradient in the Eastern Cordillera of Colombia was identified using the 16S rRNA gene sequence analysis. Hill numbers and related diversity indices were calculated to know the bacteria diversity in this collection and environments. In addition, the Bray–Curtis index was also calculated to know the differences in genera composition between sampled localities and their relationship with altitudinal gradient. The identified bacterial strains were grouped into 7 major phylogenetic groups (Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Flavobacteriia, Actinomycetes, Clostridia, and Bacilli), 38 genera, and 84 distinctive species. Diversity analysis based on Hill numbers showed that the diversity concerning bacteria inhabiting freshwater environments was consistently high. Dominant genera were Klebsiella, Serratia, and Pseudomonas, although other genera such as Bacillus, Lelliottia, and Obesumbacterium were well represented per locality. The highest bacterial diversity came from localities Cimitarra and El Carmen del Chucurí, while those originating from Santa Bárbara and Páramo del Almorzadero were relatively lower diverse. Differences in diversity were found to be mainly due to the spatial replacement of one genus by another and, to a lesser extent, to the loss or gain of taxa.
The study provides new information on factors that modulate the variation of cultivable bacterial composition in neotropics freshwater environments.
Journal Article
Exact colour evolution for jet observables
A
bstract
We perform a systematic and comprehensive analysis of sub-leading colour corrections in perturbative QCD processes involving multiple soft gluon emissions. This necessitates going beyond the standard parton shower paradigm in order to incorporate interference effects and is accomplished using the CVolver program, which simulates parton showers at the amplitude level. We can compute cross-sections with full-colour precision and also broken down explicitly in terms of their
N
c
dependence. In this paper, we focus on the jet cross-section with a veto of additional jets in some fixed region of phase-space, since this is sensitive to wide-angle, soft gluon radiation. We consider
Z
→
q
q
¯
,
H
→
gg
,
q
q
¯
→
q
q
¯
,
qg
→
qg
,
gg
→
gg
and colour-singlet →
q
q
¯
q
q
¯
. We find that non-trivial sub-leading colour effects are generally important at the 5–30% level and much more than this for certain interference contributions. Remarkably, for this observable, we find that for all of the
t
-channel gluon exchange processes that we consider, the strictly leading colour approximation, which includes the replacement
C
F
→
C
A
/
2, is an excellent approximation to the full colour result (up to an overall colour factor).
Journal Article
A review of flash glucose monitoring in type 2 diabetes
Background
Continuous glucose monitoring systems are increasingly being adopted as an alternative to self-monitoring of blood glucose (SMBG) by persons with diabetes mellitus receiving insulin therapy.
Main body
The FreeStyle Libre flash glucose monitoring system (Abbott Diabetes Care, Witney, United Kingdom) consists of a factory-calibrated sensor worn on the back of the arm which measures glucose levels in the interstitial fluid every minute and stores the reading automatically every 15 min. Swiping the reader device over the sensor retrieves stored data and displays current interstitial glucose levels, a glucose trend arrow, and a graph of glucose readings over the preceding 8 h. In patients with type 2 diabetes (T2D) receiving insulin therapy, pivotal efficacy data were provided by the 6-month REPLACE randomized controlled trial (RCT) and 6-month extension study. Compared to SMBG, the flash system significantly reduced the time spent in hypoglycemia and frequency of hypoglycemic events, although no significant change was observed in glycosylated hemoglobin (HbA1c) levels. Subsequent RCTs and real-world chart review studies have since shown that flash glucose monitoring significantly reduces HbA1c from baseline. Real-world studies in both type 1 diabetes or T2D populations also showed that flash glucose monitoring improved glycemic control. Higher (versus lower) scanning frequency was associated with significantly greater reductions in HbA1c and significant improvements in other measures such as time spent in hypoglycemia, time spent in hyperglycemia, and time in range. Additional benefits associated with flash glucose monitoring versus SMBG include reductions in acute diabetes events, all-cause hospitalizations and hospitalized ketoacidosis episodes; improved well-being and decreased disease burden; and greater treatment satisfaction.
Conclusion
T2D patients who use flash glucose monitoring might expect to achieve significant improvement in HbA1c and glycemic parameters and several associated benefits.
Journal Article
Smart Multi-Level Tool for Remote Patient Monitoring Based on a Wireless Sensor Network and Mobile Augmented Reality
Technological innovations in the field of disease prevention and maintenance of patient health have enabled the evolution of fields such as monitoring systems. One of the main advances is the development of real-time monitors that use intelligent and wireless communication technology. In this paper, a system is presented for the remote monitoring of the body temperature and heart rate of a patient by means of a wireless sensor network (WSN) and mobile augmented reality (MAR). The combination of a WSN and MAR provides a novel alternative to remotely measure body temperature and heart rate in real time during patient care. The system is composed of (1) hardware such as Arduino microcontrollers (in the patient nodes), personal computers (for the nurse server), smartphones (for the mobile nurse monitor and the virtual patient file) and sensors (to measure body temperature and heart rate), (2) a network layer using WiFly technology, and (3) software such as LabView, Android SDK, and DroidAR. The results obtained from tests show that the system can perform effectively within a range of 20 m and requires ten minutes to stabilize the temperature sensor to detect hyperthermia, hypothermia or normal body temperature conditions. Additionally, the heart rate sensor can detect conditions of tachycardia and bradycardia.
Journal Article
Handgrip strength as a predictor of 1‑year mortality after hip fracture surgery in the Colombian Andes Mountains
Summary
Hip fracture is a public health problem recognized worldwide and a potentially catastrophic threat for older persons, even carrying a demonstrated excess of mortality. Handgrip strength (HGS) has been identified as a predictor of different outcomes (mainly mortality and disability) in several groups with hip fracture.
Purpose
The aim of this study was to determine the association between low HGS and 1-year mortality in a cohort of older patients over 60 years old with fragility hip fractures who underwent surgery in the Colombian Andes Mountains.
Methods
A total of 126 patients (median age 81 years, women 77%) with a fragility hip fracture during 2019–2020 were admitted to a tertiary care hospital. HGS was measured using dynamometry upon admission, and data about sociodemographic, clinical and functional, laboratory, and surgical intervention variables were collected. They were followed up until discharge. Those who survived were contacted by telephone at one, three, and 12 months. Bivariate, multivariate, and Kaplan–Meier analyses with survival curves were performed.
Results
The prevalence of low HGS in the cohort was 71.4%, and these patients were older, had poorer functional and cognitive status, higher comorbidity, higher surgical risk, time from admission to surgery > 72 h, lower hemoglobin and albumin values, and greater intra-hospital mortality at one and three months (all p < 0.01). Mortality at one year in in patients with low HGS was 42.2% and 8.3% in those with normal HGS, with a statistically significant difference (
p
= 0.000). In the multivariate analysis, low HGS and dependent gait measured by Functional Ambulation Classification (FAC) were the factors affecting postoperative 1-year mortality in older adults with hip fractures.
Conclusion
In this study of older people with fragility hip fractures, low HGS and dependent gait were independent predictive markers of 1-year mortality.
Journal Article