The magnitude of neurocognitive impairment is overestimated in depression: the role of motivation, debilitating momentary influences, and the overreliance on mean differences

Background Meta-analyses agree that depression is characterized by neurocognitive dysfunctions relative to nonclinical controls. These deficits allegedly stem from impairments in functionally corresponding brain areas. Increasingly, studies suggest that some performance deficits are in part caused by negative task-taking attitudes such as poor motivation or the presence of distracting symptoms. A pilot study confirmed that these factors mediate neurocognitive deficits in depression. The validity of these results is however questionable given they were based solely on self-report measures. The present study addresses this caveat by having examiners assess influences during a neurocognitive examination, which were concurrently tested for their predictive value on performance. Methods Thirty-three patients with depression and 36 healthy controls were assessed on a battery of neurocognitive tests. The examiner completed the Impact on Performance Scale, a questionnaire evaluating mediating influences that may impact performance. Results On average, patients performed worse than controls at a large effect size. When the total score of the Impact on Performance Scale was accounted for by mediation analysis and analyses of covariance, group differences were reduced to a medium effect size. A total of 30% of patients showed impairments of at least one standard deviation below the mean. Conclusions This study confirms that neurocognitive impairment in depression is likely overestimated; future studies should consider fair test-taking conditions. We advise researchers to report percentages of patients showing performance deficits rather than relying solely on overall group differences. This prevents fostering the impression that the majority of patients exert deficits, when in fact deficits are only true for a subgroup.

Residual Impact Performance of ECC Subjected to Sub-High Temperatures

Despite the fact that the mechanical properties of Engineered Cementitious Composites (ECC) after high-temperature exposure are well investigated in the literature, the repeated impact response of ECC is not yet explored. Aiming to evaluate the residual impact response of ECC subjected to sub-high temperatures under repeated drop weight blows, the ACI 544-2R repeated impact test was utilized in this study. Disk impact specimens (150 mm diameter and 64 mm thickness) were prepared from the M45 ECC mixture but using polypropylene fibers, while similar 100 mm cube specimens and 100 × 100 × 400 mm prism specimens were used to evaluate the compressive and flexural strengths. The specimens were all cast, cured, heated, cooled, and tested under the same conditions and at the same age. The specimens were subjected to three temperatures of 100, 200 and 300 °C, while a group of specimens was tested without heating as a reference group. The test results showed that heating to 100 and 200 °C did not affect the impact resistance noticeably, where the retained cracking and failure impact numbers and ductility were higher or slightly lower than those of unheated specimens. On the other hand, exposure to 300 °C led to a serious deterioration in the impact resistance and ductility. The retained failure impact numbers after exposure to 100, 200, and 300 °C were 313, 257, and 45, respectively, while that of the reference specimens was 259. The results also revealed that the impact resistance at this range of temperature showed a degree of dependency on the compressive strength behavior with temperature.

Impact Analysis and Structural Optimization of Crash Barriers

The primary thought of this review is to assess the impact absorbance, strength and durability properties using non-linear finite element simulations of analytical model of crash barriers. Before manufacturing and erection of crash barriers on site are generally simulated for impact performance using finite element analysis various parameters are checked such as 1) Crash performance 2) Vehicle trajectory after collision 3) Safety of the vehicular occupant.

Mechanical and Impact Properties of Engineered Cementitious Composites Reinforced with PP Fibers at Elevated Temperatures

The repeated impact performance of engineered cementitious composites (ECCs) is not well explored yet, especially after exposure to severe conditions, such as accidental fires. An experimental study was conducted to evaluate the degradation of strength and repeated impact capacity of ECCs reinforced with Polypropylene fibers after high temperature exposure. Compressive strength and flexural strength were tested using cube and beam specimens, while disk specimens were used to conduct repeated impact tests according to the ACI 544-2R procedure. Reference specimens were tested at room temperature, while three other groups were tested after heating to 200, 400 and 600 °C and naturally cooled to room temperature. The test results indicated that the reference ECC specimens exhibited a much higher failure impact resistance compared to normal concrete specimens, which was associated with a ductile failure showing a central surface fracture zone and fine surface multi-cracking under repeated impacts. This behavior was also recorded for specimens subjected to 200 °C, while the exposure to 400 and 600 °C significantly deteriorated the impact resistance and ductility of ECCs. The recorded failure impact numbers decreased from 259 before heating to 257, 24 and 10 after exposure to 200, 400 and 600 °C, respectively. However, after exposure to all temperature levels, the failure impact records of ECCs kept at least four times higher than their corresponding normal concrete ones.

Mouldability analysis and impact performance of 3D aramid angle-interlock fabric panels for ballistic helmets

Modern ballistic helmets made from textile composites offer enhanced protection with lightweight, but the discontinuity of the reinforcing materials is a potential problem affecting the helmet performance. This work uses 3D angle-interlock fabrics to provide reinforcement continuity, and evaluates 3D through-the-thickness angle-interlock (TTAI) fabrics to study the influence of fabric structural parameters on fabric mouldabilty and ballistic performance for ballistic helmet application. The mouldability was measured through experiments and modelled numerically, and the ballistic impact test was carried out to identify the optimal fabric structures for constructing ballistic helmet shells. The results show that increase in weft density of the TTAI fabrics causes decrease in the mouldability of the TTAI fabrics, and that the addition of wadding yarns into the TTAI fabrics has little influence on fabric mouldability compared to the conventional TTAI fabrics with the same weft density. However, the involvement of wadded TTAI fabrics demonstrates a 34% increase in ballistic energy absorption and 3% higher estimated ballistic limit over the conventional counterpart. Taking both mouldability and ballistic protection into account, the wadded TTAI fabric structure is an effective continuous reinforcement for ballistic helmet shells, offering required mouldability and improved ballistic performance.

Elucidating design principles for engineering cell-derived vesicles to inhibit SARS-CoV-2 infection

The ability of pathogens to develop drug resistance is a global health challenge. The SARS-CoV-2 virus presents an urgent need wherein several variants of concern resist neutralization by monoclonal antibody therapies and vaccine-induced sera. Decoy nanoparticles (cell-mimicking particles that bind and inhibit virions) are an emerging class of therapeutics that may overcome such drug resistance challenges. To date, we lack quantitative understanding as to how design features impact performance of these therapeutics. To address this gap, here we perform a systematic, comparative evaluation of various biologically-derived nanoscale vesicles, which may be particularly well-suited to sustained or repeated administration in the clinic due to low toxicity, and investigate their potential to inhibit multiple classes of model SARS-CoV-2 virions. A key finding is that such particles exhibit potent antiviral efficacy across multiple manufacturing methods, vesicle subclasses, and virus-decoy binding affinities. In addition, these cell-mimicking vesicles effectively inhibit model SARS-CoV-2 variants that evade monoclonal antibodies and recombinant protein-based decoy inhibitors. This study provides a foundation of knowledge that may guide the design of decoy nanoparticle inhibitors for SARS-CoV-2 and other viral infections.

Context Matters: Social Psychological Factors That Underlie Academic Performance across Seven Institutions

Findings presented here demonstrate that institutional context plays an important role in the mechanisms underlying performance gaps in undergraduate biology and may affect how social psychological interventions impact performance across different learning environments.

Construct Dimensionality of Personal Energy at Work and Its Relationship with Health, Absenteeism and Productivity

Personal energy at work has become a popular topic among HRM scholars and practitioners because it has proven to impact performance. Based on the outcomes of previous research and the call for further exploration of the construct of personal energy at work, we executed this quantitative study. We explored the factor structure of the construct and its relationships with health and productivity by examining the construct that addresses four dimensions: physical, emotional, mental and spiritual energy. Data were collected from 256 employees in an international health tech company and used to analyze construct dimensionality and relationships with health, absenteeism and productivity. The results provided support for the four-dimensional structure of personal energy at work and show that the construct of personal energy at work is related to the outcomes of health, absenteeism and productivity. Implications for theory and practice, as well as directions for future research, are discussed.