Rayleigh wave group velocity maps at periods of 10-150s beneath South America

Summary Based on new data from permanent and temporary networks, we present fundamental mode Rayleigh wave group velocity maps at periods of 10-150 s related to the lithosphere beneath South America. We analyse waveform data from 1043 earthquakes, from 2002 to 2019, which were recorded by 282 stations. To isolate fundamental mode Rayleigh waves, a phase-matched filter is applied, and the measurements of group velocity are obtained from multiple filter analysis techniques. Thus, we obtain 17838 paths, covering most of the South American continent, which reach their maximum at the period of 30 s and decrease for both shorter and longer periods. We calculate average dispersion curves and probability density distribution of all measured curves to check the consistency of our dataset. Then, regionalised group velocity maps are obtained by iteratively combining the fast marching method and the subspace inversion method. The resolution of our models is assessed by checkerboard tests, which show that the synthetic group velocities are well recovered, despite some amplitude and smearing effects in some portions of the model, probably owing to regularisation and uneven raypath coverage. Compared to previous group velocity studies for South America, our models present better resolution, mainly for shorter periods. Our maps of 10 and 20 s, for example, show an excellent correlation with the sedimentary thickness (CRUST1.0) and topography density (UNB$\_$TopoDens). Regions of exposed basement and high-density are related to fast group velocities, while sedimentary basins and low-densities are observed as areas of slow group velocities. We identify small-scale fast group velocity heterogeneities that may be linked to the Rio Apa and Rio Tebicuary cratons as well as to the geochronological provinces of the Amazonian Craton. The most striking feature of our map at 40 s is a fast group velocity structure with the same NE trend of the Transbrasiliano lineament, a Neoproterozoic megashear fault that crosses a large part of the South American continent. Our long-period maps sample lithospheric depths, revealing that cratonic areas of South America, such as the Amazonian and São Francisco cratons, correlate well with fast group velocities. Another interesting feature is the presence of a strong group velocity gradient between the Paraná and Chaco-Paraná basins, which nearly coincides with the location of the Western Paraná Suture, a continental-scale gravity discontinuity. From our group velocity maps, we estimate 1D S-velocity depth profiles at ten locations in South America: Chaco-Tarija Basin, Borborema Province (BP), Amazonian Craton, Paraná Basin, Tocantins Province, Acre Basin (AcB), Altiplano-Puna Volcanic Complex, Mantiqueira Province (MP), Parnaába Basin, and São Francisco Craton. Most of our inverted S-velocity profiles show good agreement with the SL2013sv model at lithospheric depths, except the BP, AcB, and MP profiles. Particularly for the BP, a low shear-wave velocity, from about 75 to 150 km depth, is a feature that is not present in the SL2013sv model and was probably resolved in our model because of our denser raypath coverage. This decreased S-velocity may be due to a lithospheric thinning beneath the BP, as already pointed out by previous studies.

Can discreet performance banding, as compared to bio-banding, discriminate technical skills in male adolescent soccer players? A preliminary investigation

Maturation-related changes in body dimensions and performance can lead to physical mismatches and drop out from youth sport. Here, we propose a new method termed ‘discreet performance banding’ (DPB). We aimed to determine if dividing youths by actual physical performance of a discreet skill or ability (‘change or direction’ [COD] ability) could discriminate between the most and least skilled players better than a marker of implied performance, such as an assessment of biological maturation. 182 male academy Spanish soccer players (age: 13-18 years height: 143 to 188 cm; mass: 32.3 to 81.4 kg) were divided into maturation groups (Tanner stages 2 through 5) and COD groups (‘fast’, ‘intermediate’ and ‘slow’). Players’ skills (passing, shooting, ball control) were evaluated on a six-point scale with a value of ‘1’ considered ‘very bad’ and a value of ‘6’ as ‘very good’. When divided by maturity status, analyses revealed no significant differences between groups in soccer skill. However, when divided into COD groups, the analyses revealed significant differences between the fast and intermediate players ([p < 0.001] favouring the fast group) and between the intermediate and slow players ([p < 0.026] favouring the slow group). There was no significant difference in skill between the fast and slow groups, though the fast group demonstrated a higher skill level as indicated by a small effect size. Fast players were more skilful than both the intermediate and slower players, indicating that COD status can be a differentiating factor between players of different skill levels. DPB could be used to equalise competition in youth sport and to enhance the overall level of enjoyment that youths derive from engagement in sport.

An Intermittent Fasting Mimicking Nutrition Bar Extends Physiologic Ketosis in Time Restricted Eating: A Randomized, Controlled, Parallel-Arm Study

There has been increasing interest in time-restricted eating to attain intermittent fasting’s metabolic benefits. However, a more extended daily fast poses many challenges. This study was designed to evaluate the effects of a 200-calorie fasting-mimicking diet (FMD) energy bar formulated to prolong ketogenesis and mitigate fasting-associated side effects. A randomized, controlled study was conducted comparing the impact of consuming an FMD bar vs. continued water fast, after a 15-h overnight fast. Subjects in the FMD group showed a 3-h postprandial beta-hydroxybutyrate (BHB) level and 4-h postprandial BHB area under the curve (AUC0–4) that were non-inferior to those who continued with the water fast (p = 0.891 and p = 0.377, respectively). The postprandial glucose AUC0–4 in the FMD group was non-inferior to that in the water fast group (p = 0.899). A breakfast group served as a control, which confirmed that the instrument used in home glucose and ketone monitoring functioned as expected. The results indicate that FMD bar consumption does not interfere with the physiological ketogenesis associated with overnight fasting and could be used to facilitate the practice of time-restricted eating or intermittent fasting.

Cage bedding modifies metabolic and gut microbiota profiles in mouse studies applying dietary restriction

Experiments involving food restriction are common practice in metabolic research. Under fasted conditions, mice supplement their diet with cage bedding. We aimed at identifying metabolic and microbiota-related parameters affected by the bedding type. We exposed mice housed with wooden, cellulose, or corncob cage beddings to ad libitum feeding, caloric restriction (CR), or over-night (ON) fasting. Additionally, two subgroups of the ON fast group were kept without any bedding or on a metal grid preventing coprophagy. Mice under CR supplemented their diet substantially with bedding; however, the amount varied depending on the kind of bedding. Bedding-related changes in body weight loss, fat loss, cecum size, stomach weight, fecal output, blood ghrelin levels as well as a response to glucose oral tolerance test were recorded. As fiber is fermented by the gut bacteria, the type of bedding affects gut bacteria and fecal metabolites composition of CR mice. CR wood and cellulose groups showed distinct cecal metabolite and microbiome profiles when compared to the CR corncob group. While all ad libitum fed animal groups share similar profiles. We show that restriction-related additional intake of bedding-derived fiber modulates multiple physiological parameters. Therefore, the previous rodent studies on CR, report the combined effect of CR and increased fiber consumption.

FANCA Polymorphism Is Associated with the Rate of Proliferation in Uterine Leiomyoma in Korea

Uterine leiomyomas are the most common benign gynecologic tumors. This study was aimed to identify single nucleotide polymorphism of Fanconi anemia complementation group A (FANCA), associated with the rate of proliferation in uterine leiomyomas. In vitro study of patient-derived primary-cultured leiomyoma cells and direct sequencing of fresh frozen leiomyoma from each subject was conducted. Leiomyomas obtained from 44 patients who had underwent surgery were both primary-cultured and freshly frozen. Primary-cultured leiomyoma cells were divided into, according to the rate of proliferation, fast and slow groups. Single nucleotide polymorphism (SNP) of FANCA were determined from fresh frozen tissues of each patient using direct sequencing. Direct sequencing revealed a yet unidentified role of FANCA, a caretaker in the DNA damage-response pathway, as a possible biomarker molecule for the prediction of uterine leiomyoma proliferation. We identified that rs2239359 polymorphism, which causes a missense mutation in FANCA, is associated with the rate of proliferation in uterine leiomyomas. The frequency of C allele in the fast group was 35.29% while that in slow group was 11.11% (odds ratio (OR) 4.036 (1.176–13.855), p = 0.0266). We also found that the TC + CC genotype was more frequently observed in the fast group compared with that in the slow group (OR 6.44 (1.90–31.96), p = 0.0227). Taken together, the results in the current study suggested that a FANCA missense mutation may play an important regulatory role in the proliferation of uterine leiomyoma and thus may serve as a prognostic marker.

The Therapeutic Potential of Time-Restricted Fasting on Experimental Ulcerative Colitis

Aim: Intermittent fasting have been reported to have beneficial effect, in that it improves gut microbiota and lowers inflammation. This research is, however, targeted at evaluating the healing effects of fasting on ulcerative colitis in rats. Study Design: A total of eighteen Wistar rats were used for this study, and were divided into three major groups; animals that were neither induced with colitis nor fasted (group 1), animals with colitis and were allowed to fast (group 2), animals with colitis but were not allowed to fast (group 3). Place and duration of study: Department of Physiology, Ladoke Akintola University of Technology, Ogbomoso, Oyo State, between March, 2020 and July, 2020 Methodology: The weight of the 18 animals used was 180 ± 20 g. Colitis was induced by a single dose of intra-rectal administration of 1mL/100g body weight of 6% acetic acid. Animals in group 1 served as control animals. Animals in group 2 were only given access to food between 4:00 p.m and 6:30 p.m, whereas animals in group 3 were given food and water ad libitum. Animals were sacrificed ten days post colitis induction. Colonic levels of Tumor necrotic factor-alpha (TNFα), Glutathione (GSH) concentration, Superoxide dismutase (SOD), Catalase (CAT) and Myeloperoxidase (MPO) activities were measured. The blood glucose level in the animals was also recorded by the use of a glucometer. Results: There was a reduction in the concentration of TNFα and GSH, an increase in CAT and SOD activities in the colitis animals that were allowed to fast when compared with colitis animals that were not allowed to fast, ten days post colitis induction. There was also the lowering of blood sugar level, all signifying the beneficial effect of fasting on chemically-induced colitis. Thus, intermittent fasting helped the animals to heal from chemically-induced colitis.

Effect of Fat and Fasting on Post-Prandial Relative Bioavailability of Vitamin E

Objectives We hypothesized that meal fat co-administered with fat-soluble α-tocopherol (vitamin E) facilitates vitamin E absorption and increases relative bioavailability in the immediate post-prandial phase, when compared with non-fat meals. We tested this hypothesis using deuterated oral α-tocopherol co-administered with breakfast containing meal fat (40% group) and without meal fat (0% group) in hospitalized healthy women. We also evaluated the role of subsequent meals in modulating the vitamin E relative bioavailability by fasting patients for 12 h following a breakfast meal with 0% fat (0% fat-fasting group). We compared area under the curve (AUC) for oral d3-α-tocopherols %enrichment at 0–4 h, 0–12 h and 0–24 h. Methods Custom-synthesized deuterated d3-α-tocopherol was co-administered with breakfast meal with and without fat, with subsequent serial sampling. Enrolled subjects were healthy women hospitalized for 5–6 days at the NIH Clinical Research Center. Results The AUC0–4 h for 40% fat group was more than twice 0% fat group (6.4 ± 1.8 vs 2.3 ± 0.7). This difference was erased following ingestion of meals containing 30% fat at 4 h and 8 h post-dosing, with AUC0–12 h for 40% and 0% fat groups (96.8 ± 10.2 vs 107.4 ± 8.) and AUC0–24 h (254 ± 16.3 vs 301.8 ± 19.7). To evaluate the effect of fasting, we compared 0% fat group with 0% fat-fast groups. At 4 h and 8 h post-dosing, the 0% fat group received meals with 30% fat, while 0% fat-fast group remained in fasting state. We therefore predicted and found significantly higher AUC0–12 h in the 0% fat group compared with the 0% fat-fast (107.4 ± 8.1 vs 41.1 ± 5.2 P &lt; 0.001). Following meal consumption by 0% fat-fast group 12 h post-dosing, AUC0–24 h between 0% fat and 0% fat-fast groups narrowed but remained significantly different (301.8 ± 19.7 vs 207.4 ± 10.6, P &lt; 0.002) respectively. Conclusions Findings demonstrate the effect of meal fat in facilitating vitamin E absorption in the immediate post-prandial state, resulting in increased relative bioavailability. Conversely, fasting decreases vitamin E relative bioavailability. Funding Sources NIDDK Intramural Program.

Early rehabilitation protocol after Achilles tendon tenorraphy: ultrasonography and elastosonography difference with immobilization in cast: an observational study.

Background The incidence of Achilles tendon (AT) rupture increased, but there is no gold standard treatment. The aim of this study is to compare clinical and functional results of standard and fast rehabilitation program (immobilization and no weight bearing for 4 weeks vs early joint mobility and weight bearing). Methods 33 patients underwent to open achilles tenorraphy between January and July 2018 using Krackow suture.15 patients were enrolled and underwent fast rehabilitation program. A control group of 18 patients underwent surgery and standard protocol. The degree of sural triceps hypotrophy compared with the controlateral leg (calf circumference 4 cm below the anterior tibial tuberosity and the tibial length), American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Score [8], the Victorian Institute of Sports Assesement - Achilles Questionnaire (VISA-A) [9] and The Achilles tendon Total Rupture Score (ATRS) [10] were recorded at 12 months follow up. Ultrasonography and elastosonography were used to calculate different parameters both on the operated tendon and on the contralateral. Discussion Using ultrasonography, the only significant difference was recorded in the distal depth in both groups. We detected an increase of all measures in both groups comparing surgical side to the contralateral one. Using the elastosonography, the stiffness on healthy side was increased at the proximal and medial third in standard group, even if the distal third was major in fast group. On the operated side, stiffness was more on the proximal third in fast group (not statistically significant). There was an increase of tendon size on the surgical side compared to the “basal” one using US. The only statistically significant result was at distal third, and it could be due to the fact that giving an accelerated mobilization stimulates more collagen deposition, which could be a protective factor. Furthermore, at distal third of tendon we observed a greater reduction of stiffness in the fast group compared of the standard one. The results of the post-operative assessment scales are overlapping in the two groups. Clinical and functional evidence suggest that fast rehabilitation after AT surgical repair may be a first choice of treat, especially in young and active patients, because of minor local complications and higher level of satisfaction.