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1.
J Strength Cond Res ; 37(11): 2167-2177, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37883396

RESUMO

ABSTRACT: Jiménez-Lozano, M, Yáñez-García, JM, Mora-Custodio, R, Valle-Salguero, A, Díez-Fernández, DM, Franco-Márquez, F, González-Badillo, JJ, and Rodríguez-Rosell, D. Load-time and load-speed relationship in the resisted sled sprint exercise: what independent variable most accurately determines the relative load? J Strength Cond Res 37(11): 2167-2177, 2023-The aims of this study were to analyze the load-speed and load-time relationships in the resisted sled sprint exercise using different variables as relative load and to estimate the decrement of speed sprint and the increase of sprint time across different loads. Thirty young healthy men performed a progressive loading test in the countermovement jump (CMJ) exercise to determinate the load that elicited a 2 m·s-1 peak velocity (PV2-load) and in the full squat exercise to obtain the 1 repetition maximum (1RM) value and the load that elicited a 1 m·s-1 mean velocity (V1-load). In addition, subjects performed a progressive loading test in the resisted sled sprint exercise, whereas time and instantaneous speed at 10 (T10 and V10) and 20 m (T20 and V20) were measured. The independent variables used were body mass (BM), 1RM and V1-load in the squat exercise, the PV2-Load in the loaded CMJ exercise, 1RM + BM, V1-Load + BM, and PV2-Load + BM. To analyze whether relationships were dependent on individual performance obtained in unloaded sprint, the total sample was divided into 3 subgroups: high performance (T20 < 3.00 s), medium performance (T20:3.00-3.12 s), and low performance (T20 > 3.12 seconds) groups. The independent variables showing the highest relationships with time and speed in 10 and 20 m were %BM, %BM + V1-load, and %BM + PV2-load. Statistically significant differences between performance groups in %DSS (decrease of sprint speed) and %IST (increase sprint time) in 20 m were found when %BM was used as relative load, whereas there were no significant differences between groups for %BM + PV2-load or %BM + V1-load. In conclusion, the use of %BM + PV2-load and %BM + V1-load should be considered as variables for monitoring the relative load in the resisted sled sprint exercise.


Assuntos
Desempenho Atlético , Treinamento Resistido , Corrida , Masculino , Humanos , Teste de Esforço , Exercício Físico
2.
Rev Esp Enferm Dig ; 115(2): 94-95, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35748464

RESUMO

Angiosarcomas are rare tumors that usually entail a poor prognosis because of extensive invasiveness and high rates of distant metastasis. Gastrointestinal tract involvement is uncommon but may cause digestive bleeding. A definitive diagnosis requires histological and immunohistochemical testing. Metastatic lesions to the gut usually have a typical morphology, which must be identified in order to avoid delay in the diagnosis and potential treatment of this malignant condition.


Assuntos
Hemangiossarcoma , Humanos , Hemangiossarcoma/diagnóstico , Hemangiossarcoma/patologia , Hemangiossarcoma/terapia , Aorta/patologia , Biópsia
3.
Rev Esp Enferm Dig ; 115(8): 457-458, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36263832

RESUMO

We propose this variant of the clip technique as a method that assist traction during endoscopic submucosal dissection (ESD): traction on the mucosa plane using an hemoclip carrying a surgical silk and three rubber bands, before the incision, to allow easier access to the submucosa space. We propose this variant with the intention of facilitating access to ESD quickly and safely for beginners.


Assuntos
Ressecção Endoscópica de Mucosa , Humanos , Ressecção Endoscópica de Mucosa/métodos , Resultado do Tratamento , Dissecação/métodos , Mucosa , Instrumentos Cirúrgicos
4.
Bull Environ Contam Toxicol ; 110(6): 100, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37266735

RESUMO

Mercury (Hg) and stable carbon and nitrogen isotope ratios were analysed in body feathers from nestlings of white-tailed eagles (Haliaeetus albicilla) (WTE; n = 13) and Northern goshawks (Accipiter gentilis) (NG; n = 8) and in red blood cells (RBC) from NG (n = 11) from Norway. According to linear mixed model, species factor was significant in explaining the Hg concentration in feathers (LMM; p < 0.001, estimate (WTE) = 2.51, 95% CI = 1.26, 3.76), with concentrations higher in WTE (3.01 ± 1.34 µg g-1 dry weight) than in NG (0.51 ± 0.34 µg g-1 dry weight). This difference and the isotopic patterns for each species, likely reflect their diet, as WTE predominantly feed on a marine and higher trophic-chain diet compared to the terrestrial NG. In addition, Hg concentrations in RBCs of NG nestlings were positively correlated with feather Hg concentrations (Rho = 0.77, p = 0.03), supporting the potential usefulness of nestling body feathers to biomonitor and estimate Hg exposure. Hg levels in both species were generally below the commonly applied toxicity threshold of 5 µg g-1 in feathers, although exceeded in two WTE (6.08 and 5.19 µg g-1 dry weight).


Assuntos
Águias , Poluentes Ambientais , Mercúrio , Animais , Monitoramento Ambiental , Poluentes Ambientais/análise , Plumas/química , Mercúrio/análise , Noruega
5.
Int J Sports Med ; 43(12): 1033-1042, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35468640

RESUMO

This study aimed to analyze the acute mechanical, metabolic and EMG response to five resistance exercise protocols (REP) in the full squat (SQ) exercise performed with two velocity conditions: maximal intended velocity (MaxV) vs. half-maximal velocity (HalfV). Eleven resistance-trained men performed 10 REP (5 with each velocity conditions) in random order (72-96 h apart). The REP consisted of three sets of 8-3 repetitions against 45-65% 1RM. The percent change in countermovement jump (CMJ) height, velocity attained with the load that elicited a ~1.00 m·s-1 (V1-load), surface EMG variables and blood lactate concentration were assessed pre- vs. post-exercise protocols. MaxV resulted in greater percent changes (Δ: 12-25%) and intra-condition effect sizes (ES: 0.76-4.84) in loss of V1-load and CMJ height compared to HalfV (Δ: 10-16%; ES: 0.65-3.90) following all REP. In addition, MaxV showed higher post-exercise lactate concentration than HalfV (ES: 0.46-0.83; p<0.05). For EMG variables, only the Dimitrov index resulted in relevant changes after each REP, with MaxV showing greater magnitude of changes (23-38%) than HalfV (12-25%) across all REP. These results suggest that voluntary movement velocity is a key aspect to consider since it clearly determines the overall training intensity during resistance exercise.


Assuntos
Treinamento Resistido , Masculino , Humanos , Treinamento Resistido/métodos , Fadiga Muscular/fisiologia , Músculo Esquelético/fisiologia , Exercício Físico , Ácido Láctico , Força Muscular/fisiologia
6.
J Environ Manage ; 301: 113890, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34624576

RESUMO

Universal energy access is one of the targets of the Sustainable Development Goals (SDGs), and thus the deployment of electricity grids is expected to expand globally in the coming decades. However, the installation of power lines is not biodiversity-friendly. In particular, electrocution on power pylons is a major cause of bird mortality worldwide, including for some severely endangered species. Over the last decades, different studies have improved our understanding of the factors influencing the risk of electrocution in birds, but until now spatial gaps in our knowledge of these impacts and the factors driving global patterns of bird electrocution have not been assessed. In this study, we evaluated data from a total of 114 studies that provided information on bird mortality rates on power lines, and we analyzed the factors driving electrocution rates for all bird species, and then for all raptors and large eagles separately. Our results showed a high spatial distribution bias, as more than 80% of the studies were carried out in developed countries, mostly in Europe and North America. By contrast, no systematic studies have been found for Oceania and very few for South America and Africa. Europe showed the highest electrocution rates for birds, South America for raptor species and Africa for eagles. Socio-economic factors best-explained bird and raptor electrocution rates, while climate-related factors were the most influential for eagles. Contrary to our expectations, factors related to pylon design were the least influential on overall electrocution rates. Variables related to study design showed highly variable levels of influence. This could be due to the lack of standardized protocols. Although bird electrocution has been extensively studied, there are large areas where no studies have been carried out or for which data are inaccessible. This could be because in these areas the power distribution network is still sparse, or that most studies are not public or accessible to the international community. Researchers and managers should promote the publication of studies, as awareness is the first step to solving these problems. The factors identified could be applied globally to the design and planning of power grids and the identification of mortality hotspots. This would help mitigate the creation of new mortality hotspots, especially in developing countries where the installation of new power lines has been growing exponentially in recent years.


Assuntos
Aves , Espécies em Perigo de Extinção , Animais , Biodiversidade , Eletricidade , Europa (Continente)
7.
J Strength Cond Res ; 36(2): 478-485, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31895288

RESUMO

ABSTRACT: Yáñez-García, JM, Rodríguez-Rosell, D, Mora-Custodio, R, and González-Badillo, JJ. Changes in muscle strength, jump, and sprint performance in young elite basketball players: the impact of combined high-speed resistance training and plyometrics. J Strength Cond Res 36(2): 478-485, 2022-This study aimed to compare the effect of a combined resistance training (RT) and plyometrics on strength, sprint, and jump performance in basketball players of different ages. Thirty three elite basketball players from the same academy were categorized into 3 groups by chronological age: under-13 (U13, n = 11); under-15 (U15, n = 11); and under-17 (U17, n = 11). Players participated in a 6-week strength training program that included 2 sessions each week and consisted of full squats with low loads (45-60% 1 repetition maximum) and low volume (2-3 sets and 4-8 repetitions), jumps, and sprint exercises. All repetitions were performed at maximal intended velocity. In addition to strength training sessions, subjects performed 4 on court basketball training sessions plus 2 official matches per week. After training program, all 3 experimental groups resulted in significant improvements (p < 0.05-0.001) in maximal strength (Δ: 9.2-27.3%; effect size [ES]: 0.38-0.82), countermovement jump height (Δ: 6.6-11.6%; ES: 0.37-0.95), and sprint time in 10 and 20 m (Δ: -3.9 to -0.3%; ES: 0.09-0.69) for all experimental groups. Comparison between groups showed that training program was more effective in inducing improvements in most variables assessed for U13 compared with U15 (ES: 0.11-0.42) and U17 (ES: 0.20-0.43), whereas differences between U15 and U17 were relevant in jump and strength parameters (ES: 0.20-0.35). Therefore, these findings suggest that high-speed RT combined with plyometrics produces increments in several important variables, including strength, jump, and sprint, to yield high performance during a match in young basketball players. However, training program used seems to be generally less effective as the age of the basketball players increased.


Assuntos
Desempenho Atlético , Basquetebol , Treinamento Resistido , Humanos , Força Muscular , Postura
8.
J Hum Evol ; 150: 102911, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33254079

RESUMO

Rodents are a very useful tool in reconstructing the environment of the past, especially owing to their rapid response to climate change, their small home range, and their restricted habitat requirements. They are a highly diverse group of mammals, which have high reproduction rates and as a result can evolve rapidly. The abundance of their microfossil remains in archaeological and paleontological sites permits robust statistical analyses to reconstruct the past climate and environment. Recently, a number of studies have affirmed the need to deepen the climatic characterization of the European Quaternary, the Middle Pleistocene being an important stage for ascertaining how our hominin ancestors lived. The aim of this study is to characterize the climatic conditions in which hominins lived in southwestern Mediterranean Europe during the Middle Pleistocene. To reconstruct these climatic conditions, we apply the bioclimatic model to rodent assemblages from Middle Pleistocene sites with human remains (Caune de l'Arago, Sima de los Huesos, Aroeira cave, Visogliano, Trinchera Galeria, and Mollet cave). Based on the percentage distribution of the species in different climate types and applying multiple linear regressions, we estimated the mean annual temperature, the mean temperature of the coldest month, and the mean temperature of the warmest month. We compared these estimates with data collected over the last 30 years from nearby meteorological stations to obtain the differences with current climate and observe the fluctuations. The climatic conditions obtained from the results of this study show that, while in Iberia mild climatic condition prevailed, in southern France and northeastern Italy harsher weather conditions were indicated.


Assuntos
Arqueologia , Clima , Meio Ambiente , Fósseis , Hominidae , Roedores , Animais , Biota , França , Itália , Paleontologia , Portugal , Espanha
9.
Audiol Neurootol ; 26(1): 53-60, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32966975

RESUMO

OBJECTIVE: To evaluate the short-term (postoperative), medium-term (5 years), and long-term (10 and 15 years) audiometric results of patients who underwent stapedotomy and to determine specific factors associated with better postoperative outcomes. METHODS: This study is a retrospective case review of 486 ears with surgically confirmed stapes fixation who underwent microscopic small fenestra stapedotomy. Preoperative, postoperative, and medium- and long-term air conduction (AC), bone conduction (BC), and air-bone gap (ABG) were assessed. Postoperative factors associated with better postoperative outcomes were evaluated. RESULTS: At 10- and 15-year follow-ups, ABG, AC, and BC were significantly deteriorated but clinically preserved in comparison with postoperative results. According to a multiple quantile regression, younger age was associated with better postoperative results at 0.25 kHz (p = 0.003) and 4 kHz (p = 0.028) and a smaller preoperative ABG was associated with better audiometric results at 0.25 kHz (p = 0.048), 0.5 kHz (p = 0.001), and 4 kHz (p = 0.001). In addition, younger age (p = 0.001 for AC and p < 0.001 for BC) and preoperative AC PTA (p < 0.001 for AC) were significantly associated with better postoperative AC and BC PTA. CONCLUSIONS: Stapedotomy surgery provides short-, medium-, and long-term hearing benefits in our studied cohort. ABG, AC, and BC thresholds obtained after the surgery are clinically preserved in 5-, 10-, and 15-year follow-ups, with an age-expected BC deterioration. Smaller preoperative ABG and younger age were positive predictors for better postoperative ABG. Future research should address long-term subjective and quality of life outcomes.


Assuntos
Perda Auditiva Condutiva/cirurgia , Otosclerose/cirurgia , Cirurgia do Estribo/métodos , Adolescente , Adulto , Audiometria , Audiometria de Tons Puros , Condução Óssea , Estudos de Coortes , Colômbia , Feminino , Seguimentos , Perda Auditiva Condutiva/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Otosclerose/fisiopatologia , Período Pós-Operatório , Qualidade de Vida , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
10.
Dermatol Ther ; 34(5): e15074, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34338412

RESUMO

Vascular malformations (VM) are congenital, benign, and relatively frequent lesions. Scant data have been published about the epidemiology, clinical presentation, and treatment of VM from a dermatologist's perspective. The substantial differences between subtypes, broad range of specialists consulted and confusing nomenclature used over previous years may hamper a correct diagnosis. The main objective of this study is to describe VM epidemiology. As a secondary endpoint we evaluate clinical characteristics, clinical-radiological correlation and treatment approaches. We carried out an observational, descriptive, retrospective study. Cases presented to the multidisciplinary committee of our hospital from 2009 to 2019 were retrieved. Electronic medical records, monthly committee reports and the iconographic archive were reviewed and statistically analyzed. Overall, venous malformations (VeM) are the most frequent VM, followed by capillary malformations (CM), arterioVeM and lymphatic malformations (LM). Considering only patients under 16, CMs are the most frequent ones. Capillary and LMs are larger than venous or arteriovenous. While CMs are usually asymptomatic, symptomatic cases are threefold more frequent in the other subtypes. Decisions on active or conservative management depend on VM size but not location or patient age. CMs are mainly treated with laser therapy; venous with sclerotherapy or surgery; arteriovenous with surgery and lymphatic with surgery or sirolimus. Dermatologists play an important role in VM diagnosis and management. Our 10-year multidisciplinary experience should contribute to the literature and represent a practical resource for clinicians and researchers.


Assuntos
Anormalidades Linfáticas , Malformações Vasculares , Humanos , Estudos Retrospectivos , Escleroterapia/efeitos adversos , Malformações Vasculares/diagnóstico , Malformações Vasculares/epidemiologia , Malformações Vasculares/terapia , Veias
11.
Scand J Med Sci Sports ; 31(8): 1621-1635, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33829679

RESUMO

This study aimed to compare the effects of three resistance training (RT) programs differing in the magnitude of velocity loss (VL) allowed in each exercise set: 10%, 30%, or 45% on changes in strength, vertical jump, sprint performance, and EMG variables. Thirty-three young men were randomly assigned into three experimental groups (VL10%, VL30%, and VL45%; n = 11 each) that performed a velocity-based RT program for 8 weeks using only the full squat exercise (SQ). Training load (55-70% 1RM), frequency (2 sessions/week), number of sets (3), and inter-set recovery (4 min) were identical for all groups. Running sprint (20 m), countermovement jump (CMJ), 1RM, muscle endurance, and EMG during SQ were assessed pre- and post-training. All groups showed significant (VL10%: 6.4-58.6%; VL30%: 4.5-66.2%; VL45%: 1.8-52.1%; p < 0.05-0.001) improvements in muscle strength and muscle endurance. However, a significant group × time interaction (p < 0.05) was observed in CMJ, with VL10% showing greater increments (11.9%) than VL30% and VL45%. In addition, VL10% resulted in greater percent change in sprint performance than the other two groups (VL10%: -2.4%; VL30%: -1.8%; and VL45%: -0.5%). No significant changes in EMG variables were observed for any group. RT with loads of 55-70% 1RM characterized by a low-velocity loss (VL10%) provides a very effective and efficient training stimulus since it yields similar strength gains and greater improvements in sports-related neuromuscular performance (jump and sprint) compared to training with higher velocity losses (VL30%, VL45%). These findings indicate that the magnitude of VL reached in each exercise set considerably influences the observed training adaptations.


Assuntos
Desempenho Atlético/fisiologia , Força Muscular/fisiologia , Treinamento Resistido/métodos , Adulto , Teste de Esforço , Humanos , Estudos Longitudinais , Masculino , Adulto Jovem
12.
Int J Audiol ; 60(5): 365-373, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33043728

RESUMO

OBJECTIVE: Worldwide research trends on the prevalence of hearing loss within young rural populations are scarce. Current evidence suggests extended high-frequency audiometry could be a sensitive predictor to detect subclinical hearing loss. This study aimed to determine the prevalence of hearing loss through conventional pure tone (0.25-8 kHz) and extended high-frequency (9-20 kHz) audiometry tests in a group of adolescents aged 13 to 19 years old from two rural areas of Colombia. A sociodemographic and associated factor for hearing loss questionnaire was applied. DESIGN: Cross-sectional study. STUDY SAMPLE: Three hundred sixty-six adolescents aged 13 to 19 years old from two rural municipalities in Colombia: Soracá, and Palmas del Socorro. RESULTS: Hearing loss prevalence assessed through pure tone audiometry was 3.28% in right ears and 3.83% in left ears while through extended high-frequency audiometry was 14.21% and 13.11%, respectively. Associated factors found by the logistic regression were age (OR: 1.36; CI 95% 1.13-1.64) and obesity (OR: 3.74; CI 95% 1.07-13.11). CONCLUSIONS: Using 15 dB as the normal hearing threshold parameter for audiometric frequencies, our results suggest that extended high-frequency hearing loss is already widespread among rural adolescents. This highlights the need for research on extended high-frequency audiometry in rural school-aged children.


Assuntos
Perda Auditiva de Alta Frequência , Adolescente , Audiometria de Tons Puros , Limiar Auditivo , Criança , Colômbia/epidemiologia , Estudos Transversais , Humanos , Prevalência
13.
J Environ Manage ; 279: 111728, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33310346

RESUMO

This study was conducted to investigate the feasibility of Electrokinetic Remediation to remove lead and zinc from real mine tailings, collected from the Lacan's lead and zinc Mineralized Flotation Processing Plant (Markazi province, Iran). High buffering capacity, high organic matter, and heavy metal contamination were the unique characteristics of this mine tailing. Electrokinetic remediation of the mine tailings was carried out in 11 separate experiments under constant voltage gradient of 2 V/cm for 9 days. Various enhancement techniques were tested, such as 1) electrolyte conditioning using chelating agents including ethylenediaminetetraacetic acid, citric acid, acetic acid, and hydrochloric acid; 2) increasing the concentration of the catholyte solution, and 3) adding chelating agents to the soil as a pre-treatment of the tailings and the electrolyte condoning simultaneously. The concentration of each electrolyte solution was selected based on the different extraction tests that resulted in the optimal or highest extraction percentage of lead and zinc. Electrolyte conditioning, in the case of using citric acid 1 M enhanced the removal of Pb and Zn dramatically. Catholyte conditioning, using citric acid 1 M, was the most effective enhancement technique for removing Zn (38.34%); also, the best removal efficiency of Pb (51.31%) was achieved using the same electrolyte solution in both electrode chambers. Increasing the acetic acid concentration was favorable for removal of both heavy metals. Compared to catholyte conditioning, pre-treatment coupled with catholyte conditioning could not improve the removal efficiency considerably.


Assuntos
Metais Pesados , Poluentes do Solo , Irã (Geográfico) , Chumbo , Metais Pesados/análise , Poluentes do Solo/análise , Zinco/análise
14.
Health Qual Life Outcomes ; 18(1): 362, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33172467

RESUMO

BACKGROUND: Evaluation of health-related quality of life (HRQoL) is considered an important aspect of clinical assessment and health research. Chronic Otitis Media (COM) is related to the quality of life deterioration subsequent to COM symptoms, social communication impairments, and lower work performance. However, there is no reliable information regarding the impact of this disease on health and quality of life in many resource-poor countries. Therefore, we translated into Spanish the Chronic Otitis Media Questionnaire-12 (COMQ-12) for the evaluation of HRQoL of Chronic Otitis Media (COM) in adult patients. Also, we assessed the psychometric properties of the Spanish version of the questionnaire. METHODS: Two otology referral centers in Bogotá, Colombia were included. The Spanish version of COMQ-12 was applied twice to 200 adult patients with confirmed COM diagnosis and 31 healthy controls to perform the validation process and assess the internal consistency of this questionnaire. Psychometric characteristics (internal consistency, test-retest reliability, and construct validity) of the COMQ-12 were assessed. Exploratory Factor Analysis and Confirmatory Factor Analysis were conducted via structural equation modeling to test the questionnaire's structure. RESULTS: The Spanish version of the COMQ-12 showed good internal consistency (Cronbach's Alpha: 0.86, McDonald's Omega: 0.89). Coefficients corresponding to Lin's Concordance test and test-retest reliability were 0.95 and 0.83 respectively. Correlation between the Visual Analogue Scale (VAS) and the COMQ-12 was 0.68 (95% CI 0.59-0.75, p value < 0.001). Factor analysis of the Spanish version of the COMQ-12 indicated a questionnaire structure with three domains: smelly discharge related symptoms; hearing loss related symptoms; and impact on work, lifestyle, and health services. CONCLUSION: This Spanish version of the COMQ-12 showed high reliability and high internal consistency. This questionnaire can be used as an objective clinical tool to assess the HRQoL of patients who have a COM diagnosis. TRIAL REGISTRATION: Hospital Universitario Fundación Santa Fe, Ethical Committee Registration ID: CCEI-8807-2018. Hospital de San José, Ethical Committee: Record number 500, DI-I-0632-18.


Assuntos
Otite Média/psicologia , Qualidade de Vida , Inquéritos e Questionários/normas , Adulto , Estudos de Casos e Controles , Doença Crônica/psicologia , Colômbia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria/instrumentação , Reprodutibilidade dos Testes
15.
J Strength Cond Res ; 34(9): 2537-2547, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31045753

RESUMO

Rodríguez-Rosell, D, Yáñez-García, JM, Sánchez-Medina, L, Mora-Custodio, R, and González-Badillo, JJ. Relationship between velocity loss and repetitions in reserve in the bench press and back squat exercises. J Strength Cond Res 34(9): 2537-2547, 2020-This study aimed to compare the pattern of repetition velocity decline during a single set to failure performed against 4 relative loads in the bench press (BP) and full back squat (SQ) exercises. After an initial test to determine 1 repetition maximum (1RM) strength and load-velocity relationships, 20 men performed one set of repetitions to failure (MNR test) against loads of 50, 60, 70, and 80% 1RM in BP and SQ, on 8 random order sessions performed every 6-7 days. Velocity against the load that elicited a ∼1.00 m·s (V1 m·s load) was measured before and immediately after each MNR test, and it was considered a measure of acute muscle fatigue. The number of repetitions completed against each relative load showed high interindividual variability in both BP (coefficient of variation [CV]: 15-22%) and SQ (CV: 26-34%). Strong relationships were found between the relative loss of velocity in the set and the percentage of performed repetitions in both exercises (R = 0.97 and 0.93 for BP and SQ, respectively). Equations to predict repetitions left in reserve from velocity loss are provided. For a given magnitude of velocity loss within the set (15-65%), the percentages of performed repetitions were lower for the BP compared with the SQ for all loads analyzed. Acute fatigue after each set to failure was found dependent on the magnitude of velocity loss (r = 0.97 and 0.99 for BP and SQ, respectively) but independent of the number of repetitions completed by each participant (p > 0.05) for both exercises. The percentage of velocity loss against the V1 m·s load decreased as relative load increased, being greater for BP than SQ. These findings indicate that monitoring repetition velocity can be used to provide a very good estimate of the number (or percentage) of repetitions actually performed and those left in reserve in each exercise set, and thus to more objectively quantify the level of effort incurred during resistance training.


Assuntos
Fadiga Muscular/fisiologia , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Treinamento Resistido/métodos , Adulto , Estudos Transversais , Humanos , Masculino , Postura , Adulto Jovem
16.
J Strength Cond Res ; 34(10): 2867-2876, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30036284

RESUMO

Pareja-Blanco, F, Rodríguez-Rosell, D, Aagaard, P, Sánchez-Medina, L, Ribas-Serna, J, Mora-Custodio, R, Otero-Esquina, C, Yáñez-García, JM, and González-Badillo, JJ. Time course of recovery from resistance exercise with different set configurations. J Strength Cond Res 34(10): 2867-2876, 2020-This study analyzed the response to 10 resistance exercise protocols differing in the number of repetitions performed in each set (R) with respect to the maximum predicted number (P). Ten males performed 10 protocols (R(P): 6(12), 12(12), 5(10), 10(10), 4(8), 8(8), 3(6), 6(6), 2(4), and 4(4)). Three sets with 5-minute interset rests were performed in each protocol in bench press and squat. Mechanical muscle function (countermovement jump height and velocity against a 1 m·s load, V1-load) and biochemical plasma profile (testosterone, cortisol, growth hormone, prolactin, IGF-1, and creatine kinase) were assessed at several time points from 24-hour pre-exercise to 48-hour post-exercise. Protocols to failure, especially those in which the number of repetitions performed was high, resulted in larger reductions in mechanical muscle function, which remained reduced up to 48-hour post-exercise. Protocols to failure also showed greater increments in plasma growth hormone, IGF-1, prolactin, and creatine kinase concentrations. In conclusion, resistance exercise to failure resulted in greater fatigue accumulation and slower rates of neuromuscular recovery, as well as higher hormonal responses and greater muscle damage, especially when the maximal number of repetitions in the set was high.


Assuntos
Músculo Esquelético/fisiologia , Treinamento Resistido/métodos , Adulto , Creatina Quinase/sangue , Hormônio do Crescimento Humano/sangue , Humanos , Hidrocortisona/sangue , Fator de Crescimento Insulin-Like I/análise , Masculino , Fadiga Muscular/fisiologia , Postura , Descanso/fisiologia , Testosterona/sangue , Adulto Jovem
17.
Environ Res ; 176: 108543, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31260915

RESUMO

BACKGROUND: Intensification of agricultural practices has caused several negative effects to the environment. The use of fertilizers and pesticides may alter geochemical cycles or cause direct wildlife intoxication. Detrimental effects of organochlorine pesticides (OCPs) have forced the authorities to ban or restrict its use. This study evaluates the variation in levels of OCPs in a sentinel species in relation to changes in government regulations and the spatial configuration of agricultural practices around the nests. METHODS: Between 2003 and 2007, we analysed OCP levels in 256 blood samples of Eurasian Eagle-owl (Bubo bubo) chicks nesting in area of intensive commercial agriculture with historical frequent use of pesticides, in South-eastern Spain. We studied year-to-year variations in OCP concentrations and their relation with land use configuration around raptor nests by Generalized Linear Mixed Models (GLMM). RESULTS: OCPs were detected in 100% samples surveyed in 2003 and 2004, while dropped to 27% in 2005, 6.8% in 2006 and 6.3% in 2007, coinciding with the ban of OCPs. The presence of the main OCPs was related to agricultural practices. In particular, endosulfan and lindane were related to irrigated crops and urban areas, while DDT-related compounds and dieldrin were associated with dry land farming. CONCLUSIONS: OCP concentrations in blood samples of Eurasian Eagle-owls may respond quickly to the implementations of new regulations about the use of agricultural products. This raptor was confirmed as a good sentinel species allowing rapid detection of changes in pesticides use.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Clorados , Praguicidas , Agricultura , Regulamentação Governamental , Espanha
18.
J Assist Reprod Genet ; 36(10): 1975-1987, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31396849

RESUMO

PURPOSE: To determine the consequences of an altered sperm fluorescence in situ hybridization (FISH) result for ART outcomes and the indications for a sperm FISH analysis. METHODS: Data from 439 infertile men were collected. Bivariate analyses were performed to determine the association of men's age, seminal alterations, and sperm FISH indication, with the incidence of X, Y, 13, 18, and 21 sperm chromosomal abnormalities. A multivariate logistic regression analysis was performed to establish the most predictive variables for altered sperm FISH. Results from the IVF/ICSI cycles were collected for 248 out of 439 patients. Two distinct groups were established: 151 couples that used their own oocytes and 97 couples involved in egg donation programs. In both groups, ART outcomes were compared between normal and altered sperm FISH. RESULTS: Teratozoospermia and oligozoospermia were associated with sperm chromosome anomalies (p < 0.05). Indications for sperm FISH analysis with the highest predictability were teratozoospermia, male age, oligozoospermia, and implantation failure (AUC = 0.702). Embryo quality (p = 0.096), pregnancy rate (p = 0.054), and implantation rate (p = 0.089) were higher in own-oocytes couples with normal sperm FISH than in altered sperm FISH couples, although differences were not statistically significant. In donor-oocytes couples, in which high-quality embryos were transferred later than in own-oocytes couples (3.8 vs. 3.0 days), we did not identify differences in the ART outcome between normal and altered sperm FISH couples. In both groups, the possible interference of woman age was negligible. CONCLUSIONS: Sperm FISH is indicated in middle-aged oligoteratozoospermic patients with implantation failures in previous IVF/ICSI cycles. Sperm chromosome anomalies have a moderate detrimental impact on embryo quality, implantation, and pregnancy rates.


Assuntos
Hibridização in Situ Fluorescente , Oligospermia/diagnóstico , Espermatozoides/ultraestrutura , Teratozoospermia/diagnóstico , Adulto , Aberrações Cromossômicas , Implantação do Embrião/genética , Implantação do Embrião/fisiologia , Feminino , Fertilização in vitro/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Oligospermia/genética , Oligospermia/patologia , Gravidez , Taxa de Gravidez , Técnicas de Reprodução Assistida , Injeções de Esperma Intracitoplásmicas/métodos , Espermatozoides/patologia , Teratozoospermia/genética , Teratozoospermia/patologia , Doadores de Tecidos
19.
Naturwissenschaften ; 105(3-4): 31, 2018 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-29616351

RESUMO

The role of badges as indicators of contest ability has been previously described. In hummingbirds, the exhibition of a badge is expected to save energy expenditure in agonistic interactions and to favor energy intake. Here, we investigate whether variable supercilium size in the white-eared hummingbird has a role in dominance status signaling. Firstly, 45 hummingbird males were captured and their superciliums were photographed to investigate variation in size and any possible allometric relationships. Secondly, 42 male birds were used to analyze whether the supercilium has a role in dominance status signaling in a dyadic contest. We found that supercilium size varied continuously but that despite variability between individuals, there was no relationship between supercilium size and body size. However, our dyad experiment indicated that birds with larger badges were able to make more visits to the feeders than individuals with smaller badges. We suggest a status signaling function of the supercilium.


Assuntos
Comunicação Animal , Aves/anatomia & histologia , Aves/fisiologia , Predomínio Social , Animais , Tamanho Corporal , Masculino
20.
Inorg Chem ; 57(6): 3215-3222, 2018 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-29509008

RESUMO

We have prepared two new lead halides with the novel general formula of DMA7Pb4X15 (DMA = [(CH3)2NH2]+ and X = Cl- or Br-) by using an easy route under mild conditions at room temperature. These compounds exhibit an unprecedented crystal structure, are formed by layers of distorted [PbX6] octahedra, which share corners and faces, and contain intercalated DMA cations. Very interestingly, they display dielectric transitions, which are related to a partial order-disorder process of the DMA cations between 160 and 260 K. Additionally, these new layered hybrids exhibit a broadband photoluminiscent emission, which is related to the structural distortions of the [PbX6] octahedra. These findings not only open up large possibilities for future optoelectronic applications of these materials, but they also offer a novel playground for an easy modulation of electrical and optical properties of hybrid organic-inorganic materials. We anticipate that this novel A7Pb4X15 formula can be adequate to tune the family of the hybrid lead halides using other alkylammonium cations, such as methylammonium, formamidinium, or ethylammonium, to improve their photoelectronic properties.

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