Chemical alterations and nickel phytoavailability in sewage sludge-amended soil

The alteration of soil chemicals and its influence on availability (DTPA extractant method) and phytoavailability (63Ni L-value, isotopic method) of Ni was studied in sewage sludge-amended soil at different pHs. The soil pHs were 4.3, 5.3 and 5.9 and the rates of sewage sludge (SS) 0, 15, 30, 45 and 60 Mg ha-1. The chemical and physicochemical soil characteristics were altered by the SS rate and increased the Ni availability and phytoavailability. The isotopic method (63Ni L-value) was more efficient in predicting the Ni phytoavailability that the Ni-DTPA extractant in soil pHs 5.3 and 5.9.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Cell-Free Synthesis of the Mitochondrial ADP/ATP Carrier Protein of Neurospora crassa

ADP/ATP carrier protein was synthesized in heterologous cell-free systems programmed with Neurospora poly(A)-containing RNA and homologous cell-free systems from Neurospora. The apparent molecular weight of the product obtained in vitro was the same as that of the authentic mitochondrial protein. The primary translation product obtained in reticulocyte lysates starts with formylmethionine when formylated initiator methionyl-tRNA (fMet-tRNAfMet) was present. The product synthesized in vitro was released from the ribosomes into the postribosomal supernatant. The evidence presented indicates that the ADP/ATP carrier is synthesized as a polypeptide with the same molecular weight as the mature monomeric protein and does not carry an additional sequence

Lower-extremity side-to-side strength asymmetry of professional soccer players according to playing position

Previous studies have utilized screening values of 10-15% of lower-extremity side-to-side strength asymmetry in soccer players with conflicting results. The purpose of this study was to determine differences in screening values for side-to-side asymmetry in soccer players according to their playing position, as well as to compare the differences in strength asymmetry between particular playing positions. Seventy-nine Brazilian male professional soccer players (age 26.1±5.3 years; body mass 79.8±14.4 kg; body height 180.4±12.9 cm) were grouped into playing positions of: goalkeepers, side backs, central backs, central defending midfielders, central attacking midfielders, and forwards. They performed maximal knee extension and flexion concentric and knee flexion eccentric actions on their preferred and non-preferred legs at 1.047 rad·s-1. Forwards and goalkeepers had hamstrings concentric peak torque asymmetry (18.0±9.9%) and eccentric peak torque asymmetry (20.1±10.7%) significantly greater than 10% (p<.05). All other playing positions had values less than 15%. Our results indicate that the use of either 10 or 15% asymmetry cut off may result in different conclusions, which may affect decision-making regarding strength ratios. Furthermore, if 10% is used as a screening value, hamstrings strengthening programs based on bilateral equivalency should be prescribed for goalkeepers and forwards to reduce asymmetry

Implicating factors in the increase in cases of central precocious puberty (CPP) during the COVID-19 pandemic: Experience of a tertiary centre of pediatric endocrinology and review of the literature

Sexual development is a complex mechanism activated by the hypothalamic-pituitary-gonadal axis. Over the last one hundred years there has been a decline in the age at puberty onset in industrialised countries. Some Italian studies showed an increase in diagnoses of Central Precocious Puberty (CPP) during the COVID-19 pandemic. It is thus supposed that in this period there was an increased impact of factors that can influence pubertal development. Our retrospective monocentric study aimed to confirm the existence of this phenomenon and analysed possible related factors. We retrospectively evaluated clinical, laboratory, radiological and ultrasound (US) data of 154 girls referred to our Tertiary Centre of Paediatric Endocrinology from January 2019 to April 2021 for different forms of Precocious Puberty. We subdivided the cases into subgroups according to the final diagnosis: CPP, Early Puberty (EP), isolated thelarche and isolated pubarche. The observation period was subdivided into: Period 1, before lockdown (1 January 2019 - 8 March 2020) and Period 2, lockdown and the following months (9 March 2020 - 30 April 2021). Period 2 was further divided into "restrictive lockdown period" (Period 2.1) (March 2020 - 14 June 2020, in which the schools were closed) and "less restrictive lockdown period" (Period 2.2) (15 June 2020 - 30 April 2021). We analysed data regarding the use of electronic devices before and during lockdown in a group of girls with CPP diagnosed in Period 2 and we compared the data with that of a control group. Our data show an increase in the number of new diagnoses of CPP during lockdown and in the following months, compared with the previous period. We also detected a higher use of PCs and smartphones in girls with CPP diagnosed in Period 2, compared with the control group. The percentage of the presence of endometrial rhyme detected during the pelvic ultrasound was higher in girls with CPP in Period 2, compared with the previous period. Based on our data we assume there was an environmental effect on pubertal timing that calls our attention to factors such as food, use of electronic devices and stress. We will need further studies to better understand this data

Acute effects of proprioceptive neuromuscular facilitation on peak torque and muscle imbalance

Background: The effects of proprioceptive neuromuscular facilitation (PNF) stretching on muscle imbalance are not fully understood. The aim of this study was to examine the acute effects of PNF stretching on knee extension and flexion peak torque (PT), as well as the conventional and functional hamstrings to quadriceps (H:Q) ratios. Methods: Fifteen men (age = 22 ± 1 years; body mass = 76 ± 12 kg; height = 176 ± 7 cm) and fifteen women (age = 22 ± 2 years; body mass = 63 ± 8 kg; height = 161 ± 5 cm) performed concentric quadriceps and hamstrings, and eccentric hamstrings muscle actions at different angular velocities (60, 180, and 300 ◦ ·s −1 concentric; 60 and 180 ◦ ·s −1 eccentric) before and after a bout of PNF stretching, and a control condition. Results: Neither PNF or control conditions affected concentric PT or H:Q ratios (p \u3e 0.05), apart from knee extension at 60 ◦ ·s −1 in men (p = 0.001). However, there was a reduction in hamstrings eccentric PT in both control and PNF conditions for men and women (p = 0.003). Conclusions: PNF stretching of the hamstrings may not adversely affect the H:Q ratios, and consequently not negatively affect injury risk associated with muscular strength imbalances

Neuromuscular characteristics of eccentric, concentric and isometric contractions of the knee extensors

Purpose: We compared voluntary drive and corticospinal responses during eccentric (ECC), isometric (ISOM) and concentric (CON) muscle contractions to shed light on neurophysiological mechanisms underpinning the lower voluntary drive in a greater force production in ECC than other contractions. Methods: Sixteen participants (20–33 years) performed ISOM and isokinetic (30°/s) CON and ECC knee extensor contractions (110°–40° knee flexion) in which electromyographic activity (EMG) was recorded from vastus lateralis. Voluntary activation (VA) was measured during ISOM, CON and ECC maximal voluntary contractions (MVCs). Transcranial magnetic stimulation elicited motor-evoked potentials (MEPs) and corticospinal silent periods (CSP) during MVCs and submaximal (30%) contractions, and short-interval intracortical inhibition (SICI) in submaximal contractions. Results: MVC torque was greater (P \u3c 0.01) during ECC (302.6 ± 90.0 Nm) than ISOM (269.8 ± 81.5 Nm) and CON (235.4 ± 78.6 Nm), but VA was lower (P \u3c 0.01) for ECC (68.4 ± 14.9%) than ISOM (78.3 ± 13.1%) and CON (80.7 ± 15.4%). In addition, EMG/torque was lower (P \u3c 0.02) for ECC (1.9 ± 1.1 μV.Nm−1) than ISOM (2.2 ± 1.2 μV.Nm−1) and CON (2.7 ± 1.6 μV.Nm−1), CSP was shorter (p \u3c 0.04) for ECC (0.097 ± 0.03 s) than ISOM (0.109 ± 0.02 s) and CON (0.109 ± 0.03 s), and MEP amplitude was lower (P \u3c 0.01) for ECC (3.46 ± 1.67 mV) than ISOM (4.21 ± 2.33 mV) and CON (4.01 ± 2.06 mV). Similar results were found for EMG/torque and CSP during 30% contractions, but MEP and SICI showed no differences among contractions (p \u3e 0.05). Conclusions: The lower voluntary drive indicated by reduced VA during ECC may be partly explained by lower corticospinal excitability, while the shorter CSP may reflect extra muscle spindle excitation of the motoneurons from vastus lateralis muscle lengthening

Resistance training effects on pubertal children with a risk of developing pediatric dynapenia

Purpose: Many modern-day children are at risk of pediatric dynapenia (muscle weakness). We examined the effects of a 12-week resistance training (RT) program on neuromuscular function and body composition parameters in pubertal children with a risk of dynapenia. Methods: Twelve children (13.4 ± 0.9 y) with dynapenia performed a progressive RT program consisting of knee extension and flexion, bench press, abdominal crunch, back extension, lateral pull-down, elbow flexion, and upright row (1–2 sets of 10–15 repetitions/exercise) twice/week for 12 weeks. Outcome measures included one-repetition maximum (1-RM) strength, maximal voluntary isometric contraction (MVIC) torque, rate of torque development (RTD), electromyographic (EMG) activity, muscle thickness (MT), muscle quality (MQ) assessed by echo intensity (MQEI) of the knee extensors and specific tension of MVIC torque to thigh fat-free mass (MQST), and total and regional body and bone composition assessed by dual-energy X-ray absorptiometry. Changes in the measures before and after the 12-week RT and associations among the measures were analyzed by linear mixed models. Results: Significant (p \u3c 0.05) increases in 1-RM (63.9 ± 4.5%), MVIC torque (16.3 ± 17.8%), MT (18.8 ± 5.5%) and MQ (MQEI: -25.9 ± 15.2%; MQST: 15.1 ± 18.8%;) were evident from pre- to post-training. Total fat-free mass (FFM) increased by 2.3 ± 3.2% from baseline (p = 0.01), but no changes (p \u3e 0.05) in the other measures were observed. Significant (p \u3c 0.05) associations between the changes in 1-RM and/or MVIC torque and the changes in quadriceps MT, MQEI, MQST and total body FFM were evident. Conclusions: The 12-week RT was effective for improving neuromuscular and body composition parameters, and thereby reversed the risk of pediatric dynapenia

The small angle tile calorimeter in the DELPHI experiment

The {\bf S}mall angle {\bf TI}le {\bf C}alorimeter ({\bf STIC}) provides calorimetric coverage in the very forward region of the DELPHI experiment at the CERN LEP collider. The structure of the calorimeters, built with a so-called ``shashlik'' technique, gives a perfectly hermetic calorimeter and still allows for the insertion of tracking detectors within the sampling structure to measure the direction of the showering particle. A charged-particle veto system, composed of two scintillator layers, makes it possible to trigger on single photon events and provides e-$\gamma$ separat ion. Results are presented from the extensive studies of these detectors in the CERN testbeams prior to installation and of the detector performance at LEP

Effects of different combinations of concentric and eccentric resistance training programs on traditional and alternative hamstrings-to-quadriceps ratios

Resistance training is often recommended for combined increases in traditional and alternative hamstrings-to-quadriceps (H:Q) ratios in order to reduce knee strength imbalance and associated hamstrings and knee ligament injury risk. The aim of this study was to investigate the effect of different concentric and eccentric resistance training programs on traditional and alternative H:Q ratios. Forty male volunteers were assigned to one of 4 groups: concentric quadriceps and concentric hamstrings (CON/CON, n = 10), eccentric quadriceps and eccentric hamstrings (ECC/ECC, n = 10), concentric quadriceps and eccentric hamstrings (CON/ECC, n = 10), or no training (control (CNTRL), n = 10). Traditional conventional (CR) and functional (FR), alternative rate of torque development (RTD), muscle size (MS), and muscle activation (MA) H:Q ratios were measured before and after six weeks of unilateral nondominant knee extension–flexion resistance training performed on an isokinetic dynamometer. The ECC/ECC training significantly increased FR (pre = 0.75 ± 0.11; post = 0.85 ± 0.15), whereas the lack of training (CNTRL) decreased the RTD H:Q ratio (pre = 1.10 ± 0.67; post = 0.73 ± 0.33). There were no differences between groups for the other traditional and alternative ratios following resistance training protocols. These findings suggest eccentric exercise for quadriceps and hamstrings as the most beneficial training program for inducing increases in the traditional FR. However, different resistance training strategies may be needed to also elicit increases in the alternative RTD, MS, and MA H:Q ratios for fully restoring muscle balance and reducing potential hamstrings and knee ligament injury risk