Developmental neurotoxicity of cadmium on enzyme activities of crucial offspring rat brain regions

Cadmium (Cd) is an environmental contaminant known to exert significant neurotoxic effects on both humans and experimental animals. The aim of this study was to shed more light on the effects of gestational (in utero) and lactational maternal exposure to Cd (50 ppm of Cd as Cd-chloride in the drinking water) on crucial brain enzyme activities in important rat offspring brain regions (frontal cortex, hippocampus, hypothalamus, pons and cerebellum). Our study provides a brain region-specific view of the changes in the activities of three crucial brain enzymes as a result of the developmental neurotoxicity of Cd. Maternal exposure to Cd during both gestation and lactation results into significant changes in the activities of acetylcholinesterase and Na⁺,K⁺-ATPase in the frontal cortex and the cerebellum of the offspring rats, as well as in a significant increase in the hippocampal Mg²⁺-ATPase activity. These brain-region-specific findings underline the need for further research in the field of Cd-induced developmental neurotoxicity. Deeper understanding of the mechanisms underlying the neurodevelopmental deficits taking place due to in utero and early age exposure to Cd could shed more light on the causes of its well-established cognitive implications.     

Arabic translation and cross-cultural adaptation of the Sport Concussion Assessment Tool 5 (SCAT5)

The aim was to create a Modern Standard Arabic SCAT5 version for different Arabic dialects. This translation and cross-cultural adaptation was performed in eight stages: initial translations, reconciliation of translations and cultural adaptation, back translation, appraisal of back translations, validation of the translation, review and adjustment by reconciliation committee, pretesting in 12 football players and document finalisation. As an alternative to the problematic Months In Reverse Order Test (MIROT) in Arabic, the Serial 3s test (32 Arabic and 30 English participants), the Days of the Week Backwards test (DWBT), and the ‘Adding Serial 3s’ test were tested (30 English and 30 Arabic participants) for accuracy, difficulty and time of completion. The Arabic SCAT5 was similar and comparable to the original English version (7-point Likert scales =< 2). Testing of the pre-final version of the Arabic SCAT5 took 20.4 (SD 3.4) and 17.7 (SD 3.0) minutes respectively to complete and was found acceptable in terms of clarity, understandability, grammatical correctness and coherence. The Arabic Serial 3s test (subtraction version) was unsuitable due to high completion time, low pass rate and high difficulty perception [time = 47.2 (SD 28.0) s; accuracy = 55.2%; difficulty = 3.2 (SD 1.1)]. The Arabic DWBT was too fast and undemanding for concentration testing [time = 4.6 (SD 1.5) s; accuracy = 90%; difficulty = 1.1 (SD 0.3)]. The Adding Serial 3s tests produced similar completion times [18.4 (SD 6.8) vs. 21.1 (SD 5.3), p = 0.088], accuracy (100%) and self-rated difficulty [English = 2.0 (SD 0.7) vs. Arabic-speaking participants = 2.1 (SD 0.8), p = 0.512] and was therefore adopted to replace the MIROT. This culturally adapted Arabic-SCAT5 questionnaire is the first concussion assessment tool available for Arabic-speaking healthcare providers and athletes. Sport Concussion Assessment Tool 5 (SCAT5). Biol Sport. 2021;38(1):129–144.     

Reducing Voltage Losses in Cascade Organic Solar Cells while Maintaining High External Quantum Efficiencies

High photon energy losses limit the open‐circuit voltage (V_OC) and power conversion efficiency of organic solar cells (OSCs). In this work, an optimization route is presented which increases the V_OC by reducing the interfacial area between donor (D) and acceptor (A). This optimization route concerns a cascade device architecture in which the introduction of discontinuous interlayers between alpha‐sexithiophene (α‐6T) (D) and chloroboron subnaphthalocyanine (SubNc) (A) increases the V_OC of an α‐6T/SubNc/SubPc fullerene‐free cascade OSC from 0.98 V to 1.16 V. This increase of 0.18 V is attributed solely to the suppression of nonradiative recombination at the D–A interface. By accurately measuring the optical gap (E_opt) and the energy of the charge‐transfer state (E_CT) of the studied OSC, a detailed analysis of the overall voltage losses is performed. E_opt – qV_OC losses of 0.58 eV, which are among the lowest observed for OSCs, are obtained. Most importantly, for the V_OC‐optimized devices, the low‐energy (700 nm) external quantum efficiency (EQE) peak remains high at 79%, despite a minimal driving force for charge separation of less than 10 meV. This work shows that low‐voltage losses can be combined with a high EQE in organic photovoltaic devices.     

Two-stage UASB design enables activated-sludge free treatment of easily biodegradable wastewater

A two-stage lab-scale UASB reactor, incorporating a selector-type UASB prior to the main reactor was operated at 37 °C with an easily biodegradable food wastewater having a COD of 3,000 mg/L. Varying the hydraulic retention time from 25 to 5 h, the removal of COD by the two-stage process was higher than 95%. Effluent soluble COD was consistently below 75 mg/L and the methane production rate close to theoretical values. The selector UASB removed the majority of the organic load (70–90%) at high organic loading rate, i.e. between 6 and 30 g/(Ld) and the granular sludge developed was characterized by dense microbial colonies, high volatile suspended solids’ content and high substrate degradation efficiency. Design of a two-stage process, incorporating a selector and a second UASB reactor, was able to achieve stable and complete substrate degradation at overall loading rates of the order of ~10–15 g/(Ld).     

Investigating the reference domain influence in personalised models of cardiac mechanics

Biomechanics and Modeling in Mechanobiology - A major concern in personalised models of heart mechanics is the unknown zero-pressure domain, a prerequisite for accurately predicting cardiac...     

Change in kyphosis does not affect the risk of falling in postmenopausal osteopenic and osteoporotic women

Objectives:To examine the influence of the annual change in kyphosis on the risk of falling in postmenopausal osteopenic and osteoporotic women.Methods:This prospective observational study included 498 postmenopausal Greek women over the age of 50, suffering from either osteoporosis or osteopenia. Data on age, height, weight, and self-reported falls were collected. Additionally, we evaluated the degree of the kyphosis angle, the balance, the mobility, the functionality and the handgrip strength on both hands of each subject using the Debrunner kyphometer, the Berg Balance Scale, the Timed-Up-and-Go test, the 30 Seconds Sit-to-Stand test and the Jamar Hydraulic Hand Dynamometer, respectively. All the above data were recorded at the baseline visit and the 12-month follow-up visit for each participant.Results:All examined variables presented a statistically significant change at the 12-month follow-up visit. Nevertheless, the annual change in kyphosis did not show any association with the risk of falling.Conclusion:No association was shown between the annual change in kyphosis and the risk of falling in postmenopausal osteopenic and osteoporotic women, nor bears any substantial prognostic value for future falls.