Physiological Adaptations to Moderate Intensity Training in an Elite Cyclist

Efforts to improve cycling performance have to be multifactorial and respect both the intensity and duration of the sport. Elite cyclists utilize moderate intensity, long duration efforts in training to improve physiological parameters associated with performance. PURPOSE: to compare two 6-week Moderate Intensity Training (MIT), pyramidal intensity distribution (PYR) protocols and their effects on key performance variables in an elite level cyclist. METHODS: Prior to testing, this study obtained Institutional Review Board (IRB) approval and the subject signed an IRB approved informed consent. A cyclist underwent two 6-week MIT protocols following the Training Intensity Duration (TID) seen in professional cyclists’ pre competition phase. Physiological testing was conducted pre and post 6-week intervention to record maximal oxygen consumption (VO2max), maximal fat oxidation (FatMax), peak blood lactate (BLapeak) using the Australian Institute for Sport (AIS) protocol for a graded exercise test (GXT) on a cycle ergometer. A submaximal GXT was administered every two weeks to determine power output (W) at 2.0 mmol BLa as a marker for aerobic power. The first 6-wk intervention consisted of increasing duration MIT at 80-85% maximal heart rate (b*min.-1) (HRmax) from 2h to 5h/wk. The second 6-wk intervention utilized specific cadence ranges during MIT at lower volumes of 1h to 3h/wk. RESULTS: VO2max increased from 80 to 83.5 mL*kg-1*min-1 (4.4%); FatMax increased from 400W to 425W (6.25%); and BLApeak increased from 12.0 to 14.2 mmol (18.3%). Power output at 2.0 mmol BLa did not change over the 12-week intervention. CONCLUSION: MIT can be effectively used in the pre competition phase of an elite cyclist’s training to increase VO2max and FatMax power output, both important performance parameters for the long duration events for which these athletes participate

Inherited Cardiomyopathies: From Genotype to Phenotype

The heart undergoes extensive morphological, metabolic, and energetic remodeling in response to inherited, or familial, hypertrophic cardiomyopathies (FHC). Myocyte contractile perturbations downstream of Ca2+, the so-called sarcomere-controlled mechanisms, may represent the earliest indicators of this remodeling. We can now state that the dynamics of cardiac contraction and relaxation during the progression of FHC are governed by downstream mechanisms, particularly the kinetics and energetics of actin and myosin interaction to drive the trajectory of pathological cardiac remodeling. This notion is unambiguously supported by elegant studies above linking inheritable FHC-causing mutations to cardiomyopathies, known to disturb contractile function and alter the energy landscape of the heart. Although studies examining the biophysical properties of cardiac myocytes with FHC-causing mutations have yielded a cellular and molecular understanding of myofilament function, this knowledge has had limited translational success. This is driven by a critical failure in elucidating an integrated and sequential link among the changing energy landscape, myofilament function, and initiated signaling pathways in response to FHC. Similarly, there continues to be a major gap in understanding the cellular and molecular mechanisms contributing to sex differences in FHC development and progression. The primary reason for this gap is a lack of a “unifying” or “central” hypothesis that integrates signaling cascades, energetics, sex and FHC

Insulin gene polymorphisms in type I diabetes, Addison's disease and the polyglandular autoimmune syndrome type II

Background: Polymorphisms within the insulin gene can influence insulin expression in the pancreas and especially in the thymus, where self-antigens are processed, shaping the T cell repertoire into selftolerance, a process that protects from ß-cell autoimmunity. Methods: We investigated the role of the -2221Msp(C/T) and -23HphI(A/T) polymorphisms within the insulin gene in patients with a monoglandular autoimmune endocrine disease [patients with isolated type 1 diabetes (T1D, n = 317), Addison´s disease (AD, n = 107) or Hashimoto´s thyroiditis (HT, n = 61)], those with a polyglandular autoimmune syndrome type II (combination of T1D and/or AD with HT or GD, n = 62) as well as in healthy controls (HC, n = 275). Results: T1D patients carried significantly more often the homozygous genotype "CC" -2221Msp(C/T) and "AA" -23HphI(A/T) polymorphisms than the HC (78.5% vs. 66.2%, p = 0.0027 and 75.4% vs. 52.4%, p = 3.7 × 10-8, respectively). The distribution of insulin gene polymorphisms did not show significant differences between patients with AD, HT, or APS-II and HC. Conclusion: We demonstrate that the allele "C" of the -2221Msp(C/T) and "A" -23HphI(A/T) insulin gene polymorphisms confer susceptibility to T1D but not to isolated AD, HT or as a part of the APS-II

Three complete mitochondrial genomes of shortfin mako sharks, Isurus oxyrinchus, from the Atlantic and Pacific Oceans

We present complete mitogenome sequences of three shortfin mako sharks (Isurus oxyrinchus) sampled from the western Pacific, and eastern and western Atlantic oceans. Mitogenome sequence lengths ranged between 16,699 bp and 16,702 bp, and all three mitogenomes contained one non-coding control region, two rRNA genes, 22 tRNA genes, and 13 protein-coding genes. Comparative assessment of five mitogenomes from globally distributed shortfin makos (the current three and two previously published mitogenomes) yielded 98.4% identity, with the protein-coding genes ATP8, ATP6, and ND5 as the most variable regions (sequence identities of 96.4%, 96.5%, and 97.6%, respectively). These mitogenome sequences contribute resources for assessing the genetic population dynamics of this endangered oceanic apex predator

Cultivating cultural capitals in introductory algebra-based physics through reflective journaling

At a large, diverse, hispanic-serving, master’s-granting university, the Alma Project was created to support the rich connections of life experiences of science, technology, engineering, and mathematics (STEM) students that come from racially diverse backgrounds through reflective journaling. Utilizing frameworks in ethnic studies and social psychology, the Alma Project aims to make learning STEM inclusive by affirming the intersectional identities and cultural wealth that students bring into STEM classrooms. Approximately once per month students who participate in the Alma Project spend 5–10 min at the beginning of class responding to questions designed to affirm their values and purpose for studying STEM in college. Students then spend time in class sharing their responses with their peers, to the extent that they feel comfortable, including common struggles and successes in navigating through college and STEM spaces. For this study, we analyze 180 reflective journaling essays of students enrolled in General Physics I, an algebra-based introductory physics course primarily for life science majors. Students were enrolled in a required lab, a self-selected community-based learning program (Supplemental Instruction), or in a small number of instances, both. Using the community cultural wealth framework to anchor our analysis, we identified 11 cultural capitals that students often expressed within these physics spaces. Students in both populations frequently expressed aspirational, attainment, and navigational capital, while expressions of other cultural capitals, such as social capital, differ in the two populations. Our findings suggest that students bring rich and diverse perspectives into physics classrooms when asked to reflect about their lived experiences. Moreover, our study provides evidence that reflective journaling can be used as an asset-based teaching tool. By using reflective journaling in physics spaces, recognizing students’ assets has the potential for physics educators to leverage students’ lived experiences, goals, and values to make physics learning more meaningful and engaging

Exploring the Role of Mental Toughness in Bone Mineral Content: A Preliminary Study

Bone mineral content (BMC), a measure of the mineral content within a person’s bones, is an important parameter in the assessment of bone health. Changes in BMC can be indicative of bone-related conditions. Dual-energy X-ray absorptiometry (DXA) is one of the most widely used and accurate methods for measuring BMC. Sex, age, race, and BMI are known to influence BMC. Physical activity is positively related to BMC levels. Mental toughness (MT) is conceptualized as a state-like psychological resource conducive to goal-oriented pursuits and is positively linked to physical activity outcomes. The relationship between MT and BMC has not been explored. PURPOSE: To investigate the isolated effect of MT on BMC after eliminating the confounding effects of sex, age, race, and BMI. METHODS: A total of 95 individuals participated in the study across two study sites. The sample (Mage = 34.57, SD = 15.87) was predominantly White (64%), normal weight/overweight (MBMI = 25.96, SD = 4.88) males (54%). DXA scans were performed on calibrated scanners using standard procedures. MT was assessed via the Mental Toughness Index (MTI). To reduce measurement error, the MTI was administered twice, separated by a two-week interval. A linear regression model was used to analyze the relationship between BMC and the average of the two MTI scores, while controlling for sex, age, race, and BMI in MATLAB (R2023a). A Cohen’s d for MT and BMC was additionally conducted. RESULTS: The linear regression model was BMC ~ 1 + Sex + Age + Race + BMI + MT. The overall regression was statistically significant (R2 = 0.183, F(94, 88) = 2.78, p = .012). MT was found to significantly predict BMC (β = 0.093, p = .008, d = 2.7). CONCLUSION: The findings underscore the statistical significance of MT as a predictor of BMC, even when accounting for the influence of sex, age, race, and BMI. The effect size points to the practical significance of this relationship, suggesting that individuals with higher MT levels may exhibit greater BMC. Future investigations should consider incorporating demographic covariates to gain deeper insights into these relationships and conduct interventional studies to identify potential underlying mechanisms (e.g., how trainable MT could be linked, to some degree, with an increase in BMC)

Provincias geológicas, provincias fitogeográficas y ecorregiones del NOA

El IBIGEO es un instituto de investigaciones que integra profesionales que provienen de diferentes disciplinas de las Ciencias Naturales y Ambientales y en nuestra interacción cotidiana, confrontamos conceptos y definiciones que tratan principalmente sobre la diversidad del noroeste argentino. Dentro de este marco, recientemente iniciamos un estudio interdisciplinario que reúne a profesionales de la geología, biología, ingeniería agronómica, y en recursos naturales y medio ambiente, en un esfuerzo mancomunado por entender los procesos geológicos, biológicos y sociológicos. En esta contribución compartimos las diferentes interpretaciones que usamos para referirnos a distintas cosas o aquellas que son similares, e invitamos a nuestras y nuestros lectores a unirse a las primeras discusiones que surgen al encarar estudios inter y/o trans-disciplinares.Fil: Fabrezi, Marissa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta-Jujuy. Instituto de Bio y Geociencias del Noroeste Argentino. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Instituto de Bio y Geociencias del Noroeste Argentino; ArgentinaFil: Camardelli, María Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta-Jujuy. Instituto de Bio y Geociencias del Noroeste Argentino. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Instituto de Bio y Geociencias del Noroeste Argentino; ArgentinaFil: Hongn, Fernando Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta-Jujuy. Instituto de Bio y Geociencias del Noroeste Argentino. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Instituto de Bio y Geociencias del Noroeste Argentino; ArgentinaFil: Aramayo, Alejandro José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta-Jujuy. Instituto de Bio y Geociencias del Noroeste Argentino. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Instituto de Bio y Geociencias del Noroeste Argentino; ArgentinaFil: Cruz, Julio César. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta-Jujuy. Instituto de Bio y Geociencias del Noroeste Argentino. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Instituto de Bio y Geociencias del Noroeste Argentino; ArgentinaFil: Montero Lopez, Maria Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta-Jujuy. Instituto de Bio y Geociencias del Noroeste Argentino. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Instituto de Bio y Geociencias del Noroeste Argentino; ArgentinaFil: Córdoba, Gisela Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta-Jujuy. Instituto de Bio y Geociencias del Noroeste Argentino. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Instituto de Bio y Geociencias del Noroeste Argentino; ArgentinaFil: Guevara, Aranzazù. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta-Jujuy. Instituto de Bio y Geociencias del Noroeste Argentino. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Instituto de Bio y Geociencias del Noroeste Argentino; Argentin

Cambios en el estilo de vida y nutrición durante el confinamiento por SARS-CoV-2 (COVID-19) en México: un estudio observacional

Introduction: To evaluate the changes implemented in lifestyle and nutrition in the mexican population during the lockdown due to SARS-CoV-2 (COVID-19).Material and methods: Transversal study performed during the lockdown in Mexico. Data was obtained through a digital questionnaire, which was spread through social media. The questionnaire evaluated aspects related to: nutrition, well-being and lifestyle (tobacco and alcohol consumption, physical activity and sleep problems) as well as demographic variables. For the statistical analyses, the chi-square test was used to compare differences between genders, with a statistical significance of 5%, using SPSS 23.0 software.Results: A total of 1084 surveys were analyzed. The average age was 35.5±13.9 years and 66.5% (n=721) were women. In relation to eating before lockdown, 69.8% (n=757) considered their diet healthy, 6.5% (n=99) very healthy and 23.7% (n=228) unhealthy, and 2.3% (n=26) have improved their diet, despite this 17.1% (n=186) of people say they eat all the time these days. In relation to sleep, women sleep less during the period of lockdown (p=0.002) and wake up more during the night when compared to men (p<0.001).Conclusions: Factors like nutrition and sleep have alteration in that time of the lockdown. It is important to mention the relevance of these factors because the good nutrition and rest contribute for a better/ strengthening immunological system.Introducción: Evaluar el consumo de alimentos no saludables y prácticas de estilo de vida en mexicanos durante el confinamiento por SARS-CoV-2 (COVID-19).Material y métodos: Estudio transversal realizado durante parte del confinamiento en México. La recolección de datos fue realizada a través de una encuesta digital. Fueron evaluados aspectos de alimentación, bienestar y estilo de vida (consumo de alcohol y tabaco, actividad física y sueño), además de variables sociodemográficas. Para los análisis estadísticos fueron utilizadas la prueba χ2 para comparar diferencias entre género, con significancia estadística del 5%, utilizando el software SPSS 23.0.Resultados: Fueron analizadas 1084 encuestas. La edad promedio fue de 35,5±13,9 años y el 66,5% (n=721) fueron mujeres. En relación a la alimentación antes del confinamiento, 69,8% (n=757) consideraban su alimentación saludable, 6,5% (n=99) muy saludable y 23,7% (n=228) poco saludable, y el 2,3% (n=26) ha mejorado su alimentación, a pesar de esto el 17,1% (n=186) de las personas dice que en estos días come todo el tiempo. En relación al sueño, las mujeres duermen menos durante el periodo del confinamiento (p=0,002) y despiertan más durante la noche cuando se compara con los hombres (p<0,001).Conclusiones: Factores como la alimentación y el sueño presentaron alteraciones en ese período del confinamiento. Es importante destacar la relevancia de esos factores pues una buena alimentación y el descanso contribuyen para un mejor/fortalecimiento del sistema inmunológico

Uncultivated Microbial Eukaryotic Diversity: A Method to Link ssu rRNA Gene Sequences with Morphology

Protists have traditionally been identified by cultivation and classified taxonomically based on their cellular morphologies and behavior. In the past decade, however, many novel protist taxa have been identified using cultivation independent ssu rRNA sequence surveys. New rRNA “phylotypes” from uncultivated eukaryotes have no connection to the wealth of prior morphological descriptions of protists. To link phylogenetically informative sequences with taxonomically informative morphological descriptions, we demonstrate several methods for combining whole cell rRNA-targeted fluorescent in situ hybridization (FISH) with cytoskeletal or organellar immunostaining. Either eukaryote or ciliate-specific ssu rRNA probes were combined with an anti-α-tubulin antibody or phalloidin, a common actin stain, to define cytoskeletal features of uncultivated protists in several environmental samples. The eukaryote ssu rRNA probe was also combined with Mitotracker® or a hydrogenosomal-specific anti-Hsp70 antibody to localize mitochondria and hydrogenosomes, respectively, in uncultivated protists from different environments. Using rRNA probes in combination with immunostaining, we linked ssu rRNA phylotypes with microtubule structure to describe flagellate and ciliate morphology in three diverse environments, and linked Naegleria spp. to their amoeboid morphology using actin staining in hay infusion samples. We also linked uncultivated ciliates to morphologically similar Colpoda-like ciliates using tubulin immunostaining with a ciliate-specific rRNA probe. Combining rRNA-targeted FISH with cytoskeletal immunostaining or stains targeting specific organelles provides a fast, efficient, high throughput method for linking genetic sequences with morphological features in uncultivated protists. When linked to phylotype, morphological descriptions of protists can both complement and vet the increasing number of sequences from uncultivated protists, including those of novel lineages, identified in diverse environments