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This paper discusses the issues involved in calculating indices of composite reliability for ‘modular’ or ‘unitised’ assessments of the kind used in GCSEs, AS and A level examinations in England. The increasingly widespread use of on-screen marking has meant that the item-level data required for calculating indices of reliability is now routinely available for most (but not all) units of unitised assessments. Whilst it is relatively straightforward to obtain indices of reliability at unit level, it is far more complex to obtain indices at overall assessment level because of problems created by: (i) the number of different possible ‘routes’ to the final assessment; (ii) the different knowledge, skills and understanding assessed in different units; (iii) the wide variety in item type and size within and across units; (iv) the fact that the item-level data required for calculating reliability indices is not available (or does not exist) for certain units and (v) the different intended weighting of different units in the composite total and the possible distortion of these weights by use of the Uniform Mark Scale. We derive and compare several indices of composite reliability for, as an example, a three-unit assessment using both classical test theory and item response theory. We conclude that while it is desirable to derive and report indices of reliability at unit level, it is less appropriate at the level of the whole assessment. [ABSTRACT FROM PUBLISHER]

Experiments have been successfully performed culminating in functional, vascularized, three-dimensional cardiac muscle tissue. Past experience in tissue engineering has led us to the understanding that cell seeding density plays a critical role in the formation and function of both in vitro and in vivo engineered tissues. Therefore, to improve upon the mechanics of this model and to facilitate the formation of myocardial tissue with improved functional performance, we sought to optimize the seeding density of cardiomyocytes in these constructs. Neonatal cardiac myocytes were isolated from 2-day-old Fischer 344 rat hearts. Silicone chambers containing fibrin gel were seeded with varying numbers of cardiac cells (1, 5, 10, and 20 million). Control chambers were prepared using fibrin gel alone. All of the chambers were then implanted around the femoral vessels of isogenic rats. Six constructs per cell seeding density group were implanted. Histological and immunohistochemical evaluation was performed via hematoxylin and eosin, von Gieson, and α-sarcomeric actin staining protocols. Linear contractile force measurements were obtained for each construct following 4 weeks of in vivo implantation. After an implantation period of 4 weeks, the newly formed cardiac constructs contained within the chambers were harvested. The femoral vessels within the constructs were found to be patent in all cases. With direct electrical stimulation, the constructs were able to generate an average active force that varied depending on their seeding density. Constructs with seeding densities of 1, 5, 10, and 20 million cells produced an average active force of 208, 241, 151, and 108 µN, respectively. The control constructs did not generate any active force on electrical stimulation. This study demonstrates the in vivo survival, vascularization, organization, and function of transplanted myocardial cells. It is also apparent that cell seeding density plays a direct role in the force generation and mechanical properties of these engineered constructs. Among different groups using varying cell seeding densities, we found that the group with 5 million cells generated maximum active force. [ABSTRACT FROM AUTHOR]

Owing to its biodegradability, durability, low cost and potential material to replace existing commercial products in the field of engineering applications, nowadays there is a lot of interest in the field of green composites. It is formed by a mixture of biodegradable polymers and natural fibers and has a potential to replace synthetic polymer based composites. In this research work flax fibers are used as reinforcement and Poly-lactic acid (PLA) as matrix material for the development of Flax/PLA composites. The effects of processing parameters such as fiber volume fraction ranging from 25% to 50% and molding temperature ranging from 160°C to 180°C on mechanical properties of flax/PLA composites were investigated. It is concluded from the results that maximum tensile and flexural strength are recorded at 35% fiber volume fraction of flax/PLA composites developed at 170°C molding temperature. SEM analysis validated the findings obtained from the mechanical characterization. [ABSTRACT FROM AUTHOR]

Coronavirus variants are gaining strongholds throughout the globe. Despite early signals that SARS-CoV-2 coronavirus case numbers are easing up in the United States and during the middle of a (not so easy) vaccination roll out, the country has passed a grim landmark of 600,000 deaths. We contend that these numbers would have been much lower if the medical community undertook serious investigations into the potential of low doses of radiation (LDRT) as a mainstream treatment modality for COVID-19 pneumonia. LDRT has been posited to manifest anti-infectious and anti-inflammatory properties at doses of 0.3–1.0 Gy via the activation of the Nrf-2 pathway. Although some researchers are conducting well-designed clinical trials on the potential of LDRT, the deep-rooted, blind, and flawed acceptance of the Linear No-Threshold (LNT) model for ionizing radiation has led to sidelining of this promising therapy and thus unimaginable numbers of deaths in the United States. [ABSTRACT FROM AUTHOR]

In this work, partially biodegradable green composites have been developed with the help of compression molding technique. Jute fibers were selected as a reinforcement and epoxy resin as matrix material. The influence of alkali treatment on various mechanical properties of jute/epoxy composites was investigated, with concentrations ranging from 1%, 3%, 5%, 7%, and 9% NaOH solution. Various test results indicate that with an increase in concentration, tensile and flexural strength increases up to 5% concentration of NaOH, thereafter both the properties decrease, but impact strength increases up to 7% concentration and thereafter decreases. The results of mechanical characterizations were further validated through the study of morphology with scanning electron microscopy and Fourier transform infrared analysis. The optimal concentration of 5% concentration for alkali treatment of fibers have been suggested. [ABSTRACT FROM AUTHOR]

Rising environmental concerns and depletion of petrochemical resources have resulted in an increased interest in biodegradable natural fiber-reinforced polymer composites. In this research work, jute fiber has been used as a reinforcement and polylactic acid (PLA) as the matrix material to develop jute/PLA green composites with the help of compression molding technique. The effect of fiber volume fraction ranging from 25% to 50% and curing temperature ranging from 160°C to 180°C on different samples were investigated for mechanical properties and water absorption. Results obtained from various tests indicate that with an increase in the fiber volume fraction, tensile and flexural strength increases till 30% fiber fraction, thereafter decreases with further increase in fiber content. Maximum tensile and flexural strength of jute/PLA composites was obtained with 30% fiber volume fraction at 160°C curing temperature. The trend obtained from mechanical properties is further justified through the study of surface morphology using scanning electron microscopy. [ABSTRACT FROM AUTHOR]

In this era of development of new materials with good properties, is going to be a challenge when different processing methods are available with their merits and demerits concerned with reinforcement compatibility with matrix. From the last so many years, many researchers develop different kind of techniques to manufacture good quality polymer composites. In this article, effort has been made to summarize the important techniques of developing the composites along with their effects on properties and their use in various domestic and commercial purposes. [ABSTRACT FROM AUTHOR]

Nowadays, growing environmental concerns have led many researchers to work in the area of natural fiber reinforced polymer composites. In this work, jute fiber has been used as reinforcement and epoxy as matrix material to develop partially biodegradable green composite with the help of hand layup followed by compression molding technique. The effect of curing temperature ranging from 80°C to 130°C on different samples was investigated for various mechanical properties. Results obtained from the various tests indicate that with increase in curing temperature, impact strength decreases, but tensile and flexural strength increases and decreases thereafter attaining the maximum value at 100°C between aforementioned temperature range. The trend obtained for mechanical properties is further justified through the study of morphology with scanning electron microscopy, and optimum curing temperature has been suggested. [ABSTRACT FROM AUTHOR]

This present paper provides an assessment of the occurrence of nitric oxide (NO)-induced hormetic-biphasic dose/concentration relationships in biomedical research. A substantial reporting of such NO-induced hormetic effects was identified with particular focus on wound healing, tumor promotion, and sperm biology, including mechanistic assessment and potential for translational applications. Numerous other NO-induced hormetic effects have been reported, but require more development prior to translational applications. The extensive documentation of NO-induced biphasic responses, across numerous organs (e.g., bone, cardiovascular, immune, intestine, and neuronal) and cell types, suggests that NO-induced biological activities are substantially mediated via hormetic processes. These observations are particularly important because broad areas of NO biology are constrained by the quantitative features of the hormetic response. This determines the amplitude and width of the low dose stimulation, affecting numerous biomedical implications, study design features (e.g., number of doses, dose spacing, sample sizes, statistical power), and the potential success of clinical trials. Graphical Representation of occurrence of nitric oxide (NO)-induced hormetic-biphasic dose/concentration relationships in biomedical research. [Display omitted] • NO production is known to be a critical mediator of numerous cellular processes. • Nitric oxide (NO)-induces hormetic-biphasic dose/concentration relationships. • Hormetic effects were identified on wound healing, tumor promotion, sperm biology. • The median maximum stimulation was 140% and width of stimulation was 4.5-fold. • Recognition of NO induced hormesis can guide future NO research in the future. [ABSTRACT FROM AUTHOR]

Ankle instability is the most common cause of lower extremity dysfunction in physically active individuals. In spite of various treatment options available to therapists and trainers like ankle braces, taping, prophylactic ankle disc training programmes, recurrence rate of ankle sprains has been very high. Efficacy and comparison of functional balance training programme and wobble board training programme on static and dynamic measures of postural control are still confounding. The study (pretest and post-test experimental design) was aimed to determine the efficacy and comparison of functional balance training programme and wobble board training programme on subjects with functional ankle instability where measures of static and dynamic postural control (using single leg stance test and star excursion balance test) were measured following 4 weeks of balance training programme. Both the training displayed statistically non-significant changes at the end of 4 weeks of balance training following functional ankle instability. Clinical improvements in static and dynamic measures of postural control as observed provided an insight into the introduction of an alternative form of functional balance training programme for athletes with a history of recurrent ankle sprains. The presentation will be aimed to spread awareness about the significance of balance training programme in the prevention of ankle injuries in sports and importance of inculcating functional patterns of balance training in the athletic training regimens. [ABSTRACT FROM PUBLISHER]

Dupuytren's contracture is a disease involving abnormal myofibroblast proliferation and collagen deposition leading to the formation of pathologic cords in the hand. Given that Dupuytren's contractures rarely extend to the distal interphalangeal joint (DIP), affecting only 5% of patients, there are few cases reported in the literature. Collagenase injection is a frequently used option for minimally invasive treatment of Dupuytren's disease with greater than a 20-degree joint contracture. Unfortunately, there is limited research on the effectiveness of these injections in isolated DIP joint deformities. We present a case of a 61-year-old right hand-dominant male with a 2-year history of isolated right small finger Dupuytren's contracture at the DIP joint who achieved significant improvement after collagenase injection. [ABSTRACT FROM AUTHOR]

The voltage-gated potassium (Kv) 1.3 channel is widely regarded as a therapeutic target for immunomodulation in autoimmune diseases. ShK-186, a selective inhibitor of Kv1.3 channels, ameliorates autoimmune diseases in rodent models, and human phase 1 trials of this agent in healthy volunteers have been completed. In this study, we identified and characterized a large family of Stichodactyla helianthus toxin (ShK)-related peptides in parasitic worms. Based on phylogenetic analysis, 2 worm peptides were selected for study: AcKl, a 51-residue peptide expressed in the anterior secretory glands of the dog-infecting hookworm Ancylostoma caninum and the human-infecting hookworm Ancylostoma ceylanicum, and BmKl, the C-terminal domain of a metalloprotease from the lilarial worm Brugia malayi. These peptides in solution adopt helical structures closely resembling that of ShK. At doses in the nanomolar-micromolar range, they block native Kv1.3 in human T cells and cloned Kv1.3 stably expressed in L929 mouse fibroblasts. They preferentially suppress the proliferation of rat CCR7- effector memory T cells without affecting naive and central memory subsets and inhibit the delayed-type hypersen-sitivity (DTH) response caused by skin-homing effector memory T cells in rats. Further, they suppress IFNγ production by human T lymphocytes. ShK-related peptides in parasitic worms may contribute to the potential beneficial effects of probiotic parasitic worm therapy in human autoimmune diseases. [ABSTRACT FROM AUTHOR]

HsTX1 toxin, from the scorpion Heterometrus spinnifer, is a 34-residue, C-terminally amidated peptide cross-linked by four disulfide bridges. Here we describe new HsTX1 analogues with an Ala, Phe, Val or Abu substitution at position 14. Complexes of HsTX1 with the voltage-gated potassium channels Kv1.3 and Kv1.1 were created using docking and molecular dynamics simulations, then umbrella sampling simulations were performed to construct the potential of mean force (PMF) of the ligand and calculate the corresponding binding free energy for the most stable configuration. The PMF method predicted that the R14A mutation in HsTX1 would yield a > 2 kcal/mol gain for the Kv1.3/Kv1.1 selectivity free energy relative to the wild-type peptide. Functional assays confirmed the predicted selectivity gain for HsTX1[R14A] and HsTX1[R14Abu], with an affinity for Kv1.3 in the low picomolar range and a selectivity of more than 2,000-fold for Kv1.3 over Kv1.1. This remarkable potency and selectivity for Kv1.3, which is significantly up-regulated in activated effector memory cells in humans, suggest that these analogues represent valuable leads in the development of therapeutics for autoimmune diseases. [ABSTRACT FROM AUTHOR]

Electrical discharge machining (EDM) has recently been shown to be one of the most successful unconventional machining methods for meeting the requirements of today's manufacturing sector by producing complicated curved geometries in a broad variety of contemporary engineering materials. The machining efficiency of an EDM process during hexagonal hole formation on pearlitic Spheroidal Graphite (SG) iron 450/12 grade material was examined in this study utilizing peak current (I), pulse-on time (Ton), and inter-electrode gap (IEG) as input parameters. The responses, on the other hand, were the material removal rate (MRR) and overcut. During the experimental trials, the peak current ranged from 32 to 44 A, the pulse-on duration ranged from 30–120 s, and the inter-electrode gap ranged from 0.011 to 0.014 mm. Grey relational analysis (GRA) was interwoven with a fuzzy logic method to optimize the multi-objective technique that was explored in this EDM process. The effect of changing EDM process parameter values on responses was further investigated and statistically analyzed. Additionally, a response graph and response table were produced to determine the best parametric setting based on the calculated grey-fuzzy reasoning grade (GFRG). Furthermore, predictor regression models for response characteristics and GFRG were constructed, and a confirmation test was performed using randomly chosen input parameters to validate the generated models. [ABSTRACT FROM AUTHOR]