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Abstract Quiescence, a reversible state of cell-cycle arrest, is an important state during both normal development and cancer progression. For example, in glioblastoma (GBM) quiescent glioblastoma stem cells (GSCs) play an important role in re-establishing the tumour, leading to relapse. While most studies have focused on identifying differentially expressed genes between proliferative and quiescent cells as potential drivers of this transition, recent studies have shown the importance of protein oscillations in controlling the exit from quiescence of neural stem cells. Here, we have undertaken a genome-wide bioinformatic inference approach to identify genes whose expression oscillates and which may be good candidates for controlling the transition to and from the quiescent cell state in GBM. Our analysis identified, among others, a list of important transcription regulators as potential oscillators, including the stemness gene SOX2, which we verified to oscillate in quiescent GSCs. These findings expand on the way we think about gene regulation and introduce new candidate genes as key regulators of quiescence.

An attempt was made to evaluate the elongation level as a stressor on biodegradable starch films reinforced with nanoclay using a simple linear model. A total of 120 film units were subjected to increasing elongation levels and the exact break time of the failed units was monitored. Nine different attempts were made to fit the data distribution and the lognormal distribution was chosen as the most suitable because it resulted in the lowest values of the regression fit indices −2LL, AICc and BIC. Following the selection of the best fit, it was, generally, observed that an increase in the elongation level resulted in the decreasing exact break time of the films. Among several models, the best fit was provided by the simple linear model. Based on this model, the acceleration factor was estimated, and it was shown that it increased exponentially while increasing the elongation level. Finally, the probability of failure and the hazard rate of the film units as a function of the elongation level were estimated, demonstrating the applicability of this method as a tool for food packaging film failure prediction.

A destructive degradation model was applied on films made from different concentrations of starch, glycerol and nanoclay using various elongation levels as a stress variable at different stress times and stretch cycles. The log tensile quotient (logarithm of the tensile strength to the corresponding break cycle) was recorded as the response variable. The log tensile quotient increased, and the log exact break time decreased, as the elongation level increased. The treatment containing the highest starch and nanoclay and lowest glycerol content proved to be the most resistant to stress conditions and the most versatile in relation to the varying log tensile quotients, while the treatments containing the lowest nanoclay and highest glycerol contents, regardless of the starch concentration, manifested the lowest log tensile quotient at higher levels of log exact break time. According to multiple regression findings, the break cycle governed mostly the stress conditions in the degradation model, followed by the sample ID and the log exact break time. The term log tensile quotient, attempted for the first time on data concerning biodegradable films enhanced with nanoclay, seems very promising for deeper research due to its ability to retrieve predictive information from survival equations and to discriminate the difference between film structures.

Starch systems of natural antioxidants containing different starch sources (lentil, chickpea, corn, pea, and tapioca) and a variety of antioxidants (ascorbic acid, linalool, carvacrol, and cinnamic acid) are prepared using a pilot scale spray dryer. The effect of drying process on structural, morphological, and physical properties of the starch complexes is investigated. X‐ray analysis (XRD) reveals that there is a possible molecular interaction of starch with natural antioxidants. Differential Scanning Calorimetry (DSC) shows the presence of an endothermic peak ranging from 91.0 to 112.1 °C, which is most probably attributed to the dissociation temperature of starch systems. Microscopic examination shows that the spray dried particles are irregular and spherical in shape and the antioxidant molecules are uniformly distributed within the starch systems matrix. All powders have moisture content values lower than 10%. The spray dried powders exhibit high lightness (L*) values and hue angle values close to 90 implying a yellow color. Chickpea‐ascorbic acid systems exhibit the highest bulk and tapped densities values and are the most hygroscopic while tapioca‐cinnamic acid systems have the lowest ones. Principal Component Analysis (PCA) and Cluster analysis show that there is a strong relationship between the physical properties of the powders. [ABSTRACT FROM AUTHOR]

An attempt was made to evaluate the elongation level as a stressor on biodegradable starch films reinforced with nanoclay using a simple linear model. A total of 120 film units were subjected to increasing elongation levels and the exact break time of the failed units was monitored. Nine different attempts were made to fit the data distribution and the lognormal distribution was chosen as the most suitable because it resulted in the lowest values of the regression fit indices −2LL, AICc and BIC. Following the selection of the best fit, it was, generally, observed that an increase in the elongation level resulted in the decreasing exact break time of the films. Among several models, the best fit was provided by the simple linear model. Based on this model, the acceleration factor was estimated, and it was shown that it increased exponentially while increasing the elongation level. Finally, the probability of failure and the hazard rate of the film units as a function of the elongation level were estimated, demonstrating the applicability of this method as a tool for food packaging film failure prediction. [ABSTRACT FROM AUTHOR]

Two different levels (5 and 10%) of male honey bees (drones) in powder form were incorporated into wheat flour, and their impact on dough properties and on bread-quality characteristics were investigated. The incorporation of the drone powder to the wheat flour caused a decrease in the extensibility and energy of the dough in the extensograph and an increase in the dough’s maximum resistance with increasing levels of the added drone powder. The elongational viscosity values of the dough fortified with drone powder were significantly higher than those of the control wheat flour dough. The breads supplemented with 10% drone powder exhibited lower lightness (L*) values compared to the control bread. The addition of drone powder led to an increase in the total dietary fiber content and insoluble dietary fiber content in the fortified bread. Significant differences in the specific volume values were observed between the control bread and the corresponding ones with 10% drone powder. Upon storage, the moisture content of the crumb of the control bread and of the fortified breads were both significantly decreased, while the addition of the drone powder to the wheat flour bread increased the crumb hardness and gumminess but decreased the cohesiveness of the breads.

A definitive screening design was used in order to evaluate the effects of starch, glycerol and montmorillonite (MMT) concentrations, as well as the drying temperature, drying tray type and starch species, on packaging film’s functional properties. Optimization showed that in order to obtain films with the minimum possible thickness, the maximum elongation at break, the maximum tensile strength, as well as reduced water vapor permeability and low opacity, a combination of factors should be used as follows: 5.5% wt starch concentration, 30% wt glycerol concentration on a dry starch basis, 10.5% wt MMT concentration on a dry starch basis, 45 °C drying temperature, chickpea as the starch species and plexiglass as the drying tray type. Based on these results, starch films were prepared, and fresh minced meat was stored in them for 3 days. It was shown that the incorporation of MMT at 10.5% wt on a dry starch basis in the packaging films led to a decreased mesophilic and psychrotrophic bacteria growth factor compared to commercial packaging. When assessed for their biodegradability, the starch films disintegrated after 10 days of thermophilic incubation under simulated composting conditions. Finally, to prove their handling capability during industrial production, the starch films were rewound in a paper cylinder using an industrial-scale rewinding machine.

A destructive degradation model was applied on films made from different concentrations of starch, glycerol and nanoclay using various elongation levels as a stress variable at different stress times and stretch cycles. The log tensile quotient (logarithm of the tensile strength to the corresponding break cycle) was recorded as the response variable. The log tensile quotient increased, and the log exact break time decreased, as the elongation level increased. The treatment containing the highest starch and nanoclay and lowest glycerol content proved to be the most resistant to stress conditions and the most versatile in relation to the varying log tensile quotients, while the treatments containing the lowest nanoclay and highest glycerol contents, regardless of the starch concentration, manifested the lowest log tensile quotient at higher levels of log exact break time. According to multiple regression findings, the break cycle governed mostly the stress conditions in the degradation model, followed by the sample ID and the log exact break time. The term log tensile quotient, attempted for the first time on data concerning biodegradable films enhanced with nanoclay, seems very promising for deeper research due to its ability to retrieve predictive information from survival equations and to discriminate the difference between film structures. [ABSTRACT FROM AUTHOR]

The pressure response of crystalline trans‐cinnamic acid is studied by means of Raman spectroscopy up to 6 GPa. Pressure application causes the reversible shift of all the observed Raman peaks to higher frequencies and changes in their relative intensities, with the intermolecular vibrational modes being by far more sensitive to pressurization compared to the intramolecular ones. The present high‐pressure Raman data indicate the structural stability of the trans‐cinnamic acid crystal and molecular conformation up to the highest pressure attained in the experiments, the importance of the hydrogen bonding, as well as the considerable strengthening of the intermolecular interactions at elevated pressures. [ABSTRACT FROM AUTHOR]

Abstract Background Oscillatory genes, with periodic expression at the mRNA and/or protein level, have been shown to play a pivotal role in many biological contexts. However, with the exception of the circadian clock and cell cycle, only a few such genes are known. Detecting oscillatory genes from snapshot single-cell experiments is a challenging task due to the lack of time information. Oscope is a recently proposed method to identify co-oscillatory gene pairs using single-cell RNA-seq data. Although promising, the current implementation of Oscope does not provide a principled statistical criterion for selecting oscillatory genes. Results We improve the optimisation scheme underlying Oscope and provide a well-calibrated non-parametric hypothesis test to select oscillatory genes at a given FDR threshold. We evaluate performance on synthetic data and three real datasets and show that our approach is more sensitive than the original Oscope formulation, discovering larger sets of known oscillators while avoiding the need for less interpretable thresholds. We also describe how our proposed pseudo-time estimation method is more accurate in recovering the true cell order for each gene cluster while requiring substantially less computation time than the extended nearest insertion approach. Conclusions OscoNet is a robust and versatile approach to detect oscillatory gene networks from snapshot single-cell data addressing many of the limitations of the original Oscope method.

Summary: Quiescence is a dynamic process of reversible cell cycle arrest. High-level persistent expression of the HES1 transcriptional repressor, which oscillates with an ultradian periodicity in proliferative neural stem cells (NSCs), is thought to mediate quiescence. However, it is not known whether this is due to a change in levels or dynamics. Here, we induce quiescence in embryonic NSCs with BMP4, which does not increase HES1 level, and we find that HES1 continues to oscillate. To assess the role of HES1 dynamics, we express persistent HES1 under a moderate strength promoter, which overrides the endogenous oscillations while maintaining the total HES1 level within physiological range. We find that persistent HES1 does not affect proliferation or entry into quiescence; however, exit from quiescence is impeded. Thus, oscillatory expression of HES1 is specifically required for NSCs to exit quiescence, a finding of potential importance for controlling reactivation of stem cells in tissue regeneration and cancer.

Within the framework of optimisation of structural elements, in the last years, significant activity has been demonstrated towards developing new sectional designs beyond standardised forms aiming to combine aesthetic innovation, material efficiency, and weight over stiffness, together with structural reliability and manufacture cost savings. Moreover, in terms of sustainability performance, as material-weight reduction leads to less carbon emissions from production to installation processes, the pursuit of suitable materials that can correspond to this challenge becomes imperative. In this context, aluminium is lightweight and corrosion resistant, but due to its low elastic modulus, an increased cross-sectional stiffness is required. In this paper, 16 previously optimised aluminium cross-section profiles are presented and analysed using the finite element analysis software ABAQUS. The obtained ultimate compression resistances were compared with the predictions made in accordance with Eurocode 9, the direct strength method (DSM), and the continuous strength method (CSM). The percentage of difference of these design methods with respect to FE results is depicted. The outcomes point out the vagueness in accuracy of the prediction methods, particularly in reference to stocky or slender cross-sections.

Black and green olive pulp was added to wheat bread formulation at different levels (5, 10, 15%) with the aim to improve its nutritional value by enhancing the phenolic content and antioxidant capacity. Additionally, the effects of the fortification with olive pulp on the physical characteristics, staling rate and overall consumer acceptability of the formulated breads were explored. Both olive pulps exhibited significantly higher antioxidant activity than refined wheat flour. Baking imparted an impressive increase in TPC, TFC and antioxidant activity of breads as revealed by comparison of experimental with theoretical values but returned significant differences only in the case of TPC when a two-tailed t-test for paired data was applied. Texture measurements showed a substantial increase in hardness with storage along with decreasing loaf volume and increased density. Hydroxytyrosol was the major phenolic compound of fortified breads followed by tyrosol. Olive pulp could be incorporated in a bread formulation without interfering with the general sensory acceptability.

There has been an increasing interest in possible connections between autism spectrum disorder (ASD) and schizophrenia in the last decade. Neuropsychological comparison studies have, however, been few. The present study examined similarities and differences in intellectual and executive functioning between adults with Asperger syndrome (AS) and adults with schizophrenic psychosis (SP). A group with AS and a group with SP were assessed neuropsychologically with WAIS-III and D-KEFS. Similarities were found between groups, as displayed by an uneven cognitive profile, limitations in working memory, processing speed and some aspects of executive functioning. Full Scale IQ was higher in the AS group. These results add to the current research illuminating similarities and differences between ASD and schizophrenia on a cognitive level.