Increased Placental Cell Senescence and Oxidative Stress in Women with Pre-Eclampsia and Normotensive Post-Term Pregnancies

Up to 11% of pregnancies extend to post-term with adverse obstetric events linked to pregnancies over 42 weeks. Oxidative stress and senescence (cells stop growing and dividing by irreversibly arresting their cell cycle and gradually ageing) can result in diminished cell function. There are no detailed studies of placental cell senescence markers across a range of gestational ages, although increased levels have been linked to pre-eclampsia before full term. This study aimed to determine placental senescence and oxidative markers across a range of gestational ages in women with uncomplicated pregnancies and those with a diagnosis of pre-eclampsia. Placentae were obtained from 37 women with uncomplicated pregnancies of 37–42 weeks and from 13 cases of pre-eclampsia of 31⁺²–41⁺² weeks. The expression of markers of senescence, oxidative stress, and antioxidant defence (tumour suppressor protein p16^INK4a, kinase inhibitor p21, interleukin-6 (IL-6), NADPH oxidase 4 (NOX4), glutathione peroxidases 1, 3, and 4 (GPx1, GPx3, and GPx4), placental growth factor (PlGF), and soluble fms-like tyrosine kinase-1 (sFlt-1)) genes was measured (quantitative real-time PCR). Protein abundance of p16^INK4a, IL-6, NOX4, 8-hydroxy-2′-deoxy-guanosine (8-OHdG), and PlGF was assessed by immunocytochemistry. Placental NOX4 protein was higher in post-term than term deliveries and further increased by pre-eclampsia (p < 0.05 for all). P21 expression was higher in post-term placentae (p = 0.012) and in pre-eclampsia (p = 0.04), compared to term. Placental P16^INK4a protein expression was increased post-term, compared to term (p = 0.01). In normotensive women, gestational age at delivery was negatively associated with GPx4 and PlGF (mRNA and protein) (p < 0.05 for all), whereas a positive correlation was seen with placental P21, NOX4, and P16^INK4a (p < 0.05 for all) expression. Markers of placental oxidative stress and senescence appear to increase as gestational age increases, with antioxidant defences diminishing concomitantly. These observations increase our understanding of placental health and may contribute to assessment of the optimal gestational age for delivery.     

Kitkaite NiTeSe,an Ambient-Stable Layered Dirac Semimetal with Low-Energy Type-II Fermions with Application Capabilities in Spintronics and Optoelectronics

The emergence of Dirac semimetals has stimulated growing attention, owing to the considerable technological potential arising from their peculiar exotic quantum transport related to their nontrivial topological states. Especially, materials showing type-II Dirac fermions afford novel device functionalities enabled by anisotropic optical and magnetotransport properties. Nevertheless, real technological implementation has remained elusive so far. Definitely, in most Dirac semimetals, the Dirac point lies deep below the Fermi level, limiting technological exploitation. Here, it is shown that kitkaite (NiTeSe) represents an ideal platform for type-II Dirac fermiology based on spin-resolved angle-resolved photoemission spectroscopy and density functional theory. Precisely, the existence of type-II bulk Dirac fermions is discovered in NiTeSe around the Fermi level and the presence of topological surface states with strong (≈50%) spin polarization. By means of surface-science experiments in near-ambient pressure conditions, chemical inertness towards ambient gases (oxygen and water) is also demonstrated. Correspondingly, NiTeSe-based devices without encapsulation afford long-term efficiency, as demonstrated by the direct implementation of a NiTeSe-based microwave receiver with a room-temperature photocurrent of 2.8 µA at 28 GHz and more than two orders of magnitude linear dynamic range. The findings are essential to bringing to fruition type-II Dirac fermions in photonics, spintronics, and optoelectronics.     

The use of continuous exposure data for predicting CTS in fish processing operators

Carpal tunnel syndrome (CTS) remains one of the most commonly reported and studied work related musculoskeletal disorders. Categorical representations of exposures has been critical in identifying associations between risk factors and CTS, however, quantification of exposure-response relationships require using continuous exposure data. Also, few interactions between risk factors, especially between risk factor categories, have been investigated. The objectives of this study were to investigate the utility of using continuous exposure data and to identify interaction effects of risk factors, both within and between risk factor categories, for predicting CTS. A cross sectional study was performed at a fish processing facility in which 53 participants were evaluated during normal task performance. Due to task asymmetry, each hand was considered separately, providing 106 hands for analysis. Direct measurement and a questionnaire were used to quantify exposures to common occupational and personal risk factors. Stepwise logistic regression analysis was performed to identify three models for predicting CTS and assess predictive ability using: occupational risk factors only (three-way interactions considered), personal risk factors only (two-way interactions considered), and a mixed model considering two-way interactions across risk factor categories and previously identified significant interactions. Models including only occupational or personal risk factors were moderately accurate overall (73% and 77% respectively), but were not sensitive in differentiating between CTS cases and non-cases (39% and 33% respectively). The mixed model was found to be accurate (88%) and sensitive (78%), though only one interaction effect was included. The results of this study illustrate the importance of using continuous exposure data, especially in job tasks where exposures to occupational risk factors is similar, when differentiating between high and low risk job tasks.     

Tungsten carbide modified high surface area carbon as fuel cell catalyst support

Phase pure WC nanoparticles were synthesized on high surface area carbon black (800 m² g⁻¹) by a temperature programmed reaction (TPR) method. The particle size of WC can be controlled under 30 nm with a relatively high coverage on the carbon surface. The electrochemical testing results demonstrated that the corrosion resistance of carbon black was improved by 2-fold with a surface modification by phase pure WC particles. However, the WC itself showed some dissolution under potential cycling. Based on the X-ray diffraction (XRD) and inductively coupled plasma (ICP) analysis, most of the WC on the surface was lost or transformed to oxides after 5000 potential cycles in the potential range of 0.65-1.2 V. The Pt catalyst supported on WC/C showed a slightly better ORR activity than that of Pt/C, with the Pt activity loss rate for Pt/WC/C being slightly slower compared to that of Pt/C. The performance and decay rate of Pt/WC/C were also evaluated in a fuel cell.     

A model to predict accommodations needed by disabled persons.

In this paper, several approaches to assist employers in the accommodation process for disabled employees are discussed and a mathematical model is proposed to assist employers in predicting the accommodation level needed by an individual with a mobility-related disability. This study investigates the validity and reliability of this model in assessing the accommodation level needed by individuals utilizing data collected from twelve individuals with mobility-related disabilities. Based on the results of the statistical analyses, this proposed model produces a feasible preliminary measure for assessing the accommodation level needed for persons with mobility-related disabilities. Suggestions for practical application of this model in an industrial setting are addressed.     

An investigation of cumulative trauma disorders in the construction industry

Disorders associated with repeated trauma were the most common occupational illness in 1991, accounting for 61% of all occupational illnesses (Bureau of Labor Statistics). Research on cumulative trauma injuries in the construction industry is scarce. Therefore, the purpose of this research was to investigate factors associated with the development of cumulative trauma disorders (CTDs) in the construction industry. Additionally, this research evaluates the types of CTDs most prevalent in the construction industry. Results of this research show seven common CTDs prevalent in the construction industry: arpal Tunnel Syndrome, Tennis Elbow, Trigger Finger, Arthritis of the Thumb, Thumb/Wrist Tendinitis, Vibration Syndrome and Impingement. An index was developed to rank tasks based on possible development of CTDs by quantifying factors that contribute to the occurrence of these CTDs such as tool design, work task design, awkward posture, repetition, and application of force.     

Revisiting the Chemical Stability of Germanium Selenide (GeSe) and the Origin of its Photocatalytic Efficiency

Recently, germanium selenide (GeSe) has emerged as a promising van der Waals semiconductor for photovoltaics, solar light harvesting, and water photoelectrolysis cells. Contrary to previous reports claiming perfect ambient stability based on experiments with techniques without surface sensitivity, here, by means of surface-science investigations and density functional theory, it is demonstrated that actually both: i) the surface of bulk crystals; and ii) atomically thin flakes of GeSe are prone to oxidation, with the formation of self-assembled germanium-oxide skin with sub-nanometric thickness. Surface oxidation leads to the decrease of the bandgap of stoichiometric GeSe and GeSe_1−x, while bandgap energy increases upon surface oxidation of Ge_1−xSe. Remarkably, the formation of a surface oxide skin on GeSe crystals plays a key role in the physicochemical mechanisms ruling photoelectrocatalysis: the underlying van der Waals semiconductor provides electron–hole pairs, while the germanium-oxide skin formed upon oxidation affords the active sites for catalytic reactions. The self-assembled germanium-oxide/germanium-selenide heterostructure with different bandgaps enables the activation of photocatalytic processes by absorption of light of different wavelengths, with inherently superior activity. Finally, it is discovered that, depending on the specific solvent-GeSe interaction, the liquid phase exfoliation of bulk crystals can induce the formation of Se nanowires.     

Studies on a low Reynolds number airfoil for small wind turbine applications

In contrast to large horizontal axis wind turbines (HAWTs) that are located in areas dictated by optimum wind conditions, small wind turbines are required for producing power without necessarily the best wind conditions. A low Reynolds number airfoil was designed after testing a number of low Reynolds number airfoils and then making one of our own; it was tested for use in small HAWTs. Studies using XFOIL and wind tunnel experiments were performed on the new airfoil at various Reynolds numbers. The pressure...     

Fermented dairy products: knowledge and consumption.

PURPOSE: Much has been published on the nutritional and health benefits of fermented dairy products, especially those containing probiotic microorganisms. However, consumers may not be familiar with the term "fermented dairy products," and therefore may not take full advantage of them. University students' knowledge and consumption patterns of fermented dairy products were assessed. METHODS: University students (n=223) completed a survey consisting of a section on demographics and another on knowledge and consumption patterns. RESULTS: The majority of respondents (62%) were not familiar with the term "fermented dairy products." Most respondents consumed yogourt a few times a week (40%) or a few times a month (30%). Almost all respondents (92%) were unable to identify the difference between regular and probiotic yogourt. Most respondents (93%) had not heard of acidophilus milk, but the majority (65%) would be willing to try it. Most respondents were unsure whether sour cream (65%), yogourt beverages (74%), and cheddar cheese (61%) were fermented dairy products. Sixty percent of respondents never consumed yogourt drinks. CONCLUSIONS: Education is needed about fermented dairy products, especially probiotics, and their nutritional and health benefits. Such education may increase their acceptability and consumption.