709 research outputs found
Bioelectrical impedance vector analysis (BIVA) in sport and exercise: Systematic review and future perspectives
Background Bioelectrical impedance vector analysis (BIVA) is a general concept that includes all methodologies used in the analysis of the bioelectrical vector, whereas the "classic" BIVA is a patented methodology included among these methods of analysis. Once this was clarified, the systematic review of the literature provides a deeper insight into the scope and range of application of BIVA in sport and exercise. Objective The main goal of this work was to systematically review the sources on the applications of BIVA in sport and exercise and to examine its usefulness and suitability as a technique for the evaluation of body composition, hydration status, and other physiological and clinical relevant characteristics, ultimately to trace future perspectives in this growing area, including a proposal for a research agenda. Methods Systematic literature searches in PubMed, SPORTDiscus and Scopus databases up to July, 2017 were conducted on any empirical investigations using phase-sensitive bioimpedance instruments to perform BIVA within exercise and sport contexts. The search included healthy sedentary individuals, physically active subjects and athletes. Result Nineteen eligible papers were included and classified as sixteen original articles and three scientific conference communications. Three studies analysed short-term variations in the hydration status evoked by exercise/training through whole-body measurements, eleven assessed whole-body body composition changes induced by long-term exercise, four compared athletic groups or populations using the whole-body assessment, and two analysed bioelectrical patterns of athletic injuries or muscle damage through localised bioimpedance measurements. Conclusions BIVA is a relatively new technique that has potential in sport and exercise, especially for the assessment of soft-tissue injury. On the other hand, the current tolerance ellipses of “classic” BIVA are not a valid method to identify dehydration in individual athletes and a new approach is needed. “Specific” BIVA, a method which proposes a correction of bioelectrical values for body geometry, emerges as the key to overcome “classic” BIVA limitations regarding the body composition assessment. Further research establishing standardised testing procedures and investigating the relationship between physiology and the bioelectrical signal in sport and exercise is needed. © 2018 Castizo-Olier et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Scopu
On unbounded p-summable Fredholm modules
We prove that odd unbounded p-summable Fredholm modules are also bounded
p-summable Fredholm modules (this is the odd counterpart of a result of A.
Connes for the case of even Fredholm modules)
Cybersecurity capabilities and cyber-attacks as drivers of investment in cybersecurity systems: A UK survey for 2018 and 2019
Our study explores how cyber-capabilities and cyber-attacks drive investment in cybersecurity systems. We assume that cybersecurity investment is a strategic decision in the organizations. To analyze this research question, we make use of the Cyber Security Breaches Survey data, with a sample consisting of 4,163 UK organizations in the periods 2018 to 2019, and employ machine learning techniques (ANN and K-mean cluster). The study extends the current literature on cybersecurity systems and improves our understanding of it in several ways. First, it provides evidence for how the cybersecurity systems are developed in organizations. Second, regarding what factors affect investment in cybersecurity systems, it shows that organizations invest in cybersecurity based on their cybersecurity capabilities and the experienced cyber-attacks. Third, from a managerial point of view, the paper contributes to understanding cybersecurity within the management of the organization
Preparation and antimicrobial evaluation of polyion complex (PIC) nanoparticles loaded with polymyxin B
AbstractHere, we describe novel polyion complex (PIC) particles for the delivery of Polymyxin B (Pol-B), an antimicrobial peptide currently used in the clinic as a last resort antibiotic against multidrug-resistant gram-negative bacteria. A range of conditions for the controlled assembly of Pol-B with poly(styrene sulphonate) (PSS) has been identified which let us prepare stable colloidal PIC particles. This way, PIC particles containing different Pol-B:PSS ratios have been prepared and their stability under simulated physiological conditions (i.e. pH, osmotic pressure and temperature) characterised. Furthermore, preliminary evaluation of the antimicrobial activity of these Pol-B containing PIC particles has been performed, by monitoring their effect on the growth of Pseudomonas aeruginosa, an opportunistic gram-negative bacterium
Recommended from our members
The formation of self-management teams in Higher Education institutions. Satisfaction and effectiveness
This paper explores how self-management work groups are formed in higher education institutions and how this affects the effectiveness of the teams. For this, we investigated the experiences of 560 students who were members of self-management learning teams, using factorial analysis, cluster analysis and ordinal logit regression. We focus on self-management teams, where students form work groups autonomously, and making decisions with whom to collaborate. Thus, students influence the composition of their groups, which will condition the internal dynamic of teams, and its subsequent effect on the effectiveness of the groups. Our paper contributes to the literature on student-centred perspectives highlighting how the formation of self-management teams has an impact on their satisfaction and effectiveness. Moreover, we identify four criteria (competencies, academic level, social relationships, and ad hoc) during the formation of self-management teams that have a differential impact on the effectiveness and potential conflict in the team. Additionally, our results reveal three groups of students, regarding the formation criteria of self-management teams: a first group where the academic level criteria prevails, a second group based on competencies, and finally, a group that combines social relationships and ad hoc criteria. Moreover, we find that self-management teams based on the competencies and academic level criteria have a higher level of effectiveness and satisfaction than the formation of self-management teams based on social relations and ad hoc decisions. Moreover, the results show that the exclusive use of academic level as a formation criteria is potentially a source of conflict in the self-management team
Intraoperative radiotherapy electron boost followed by moderate doses of external beam radiotherapy in resected soft-tissue sarcoma of the extremities
To analyze the patterns of failure and the toxicity profile of
intraoperative electron beam radiotherapy (IOERT) after resection of soft tissue
sarcomas of the extremities (STS). PATIENTS AND METHODS: Forty-five patients with
extremity STS were treated with IOERT and moderate-dose postoperative
radiotherapy (45-50 Gy). Twenty-six patients were treated for primary disease
(PD) and 19 patients for an isolated recurrence (ILR). Tumor size was >5 cm
(maximum diameter) in 36 patients (80%), and high-grade histology in PD patients
was present in 14 patients (54%). In nine patients, IOERT was used alone, due to
previous irradiation or patient refusal. Chemotherapy (neoadjuvant and/or
adjuvant) was mainly given to high-grade tumors. RESULTS: Nine patients relapsed
in the extremity (20%), and 12 patients in distant sites (28%). Actuarial local
control at 5 years was 88% for patients with negative/close margins and 57% for
patients presenting positive margins (P=0.04). Five patients (11%) developed
neuropathy associated with the treatment. Extremity preservation was achieved in
40 patients (88%). With a median follow-up of 93 months (range: 27-143 months)
for the patients at risk, 25 patients remain alive (a 7-year actuarial survival
rate of 75% for PD and 47% for ILR; P=0.01). CONCLUSIONS: IOERT combined with
moderate doses of external beam irradiation yields high local control and
extremity preservation rates in resected extremity STS. Peripheral nerves in the
IOERT field are dose-limiting structures requiring a dose compromise in the IOERT
component to avoid severe neurological damage
- …