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The subject of this study is the synthesis and biological evaluation of anoplin-based (Gly-Leu-Leu 3 -Lys-Arg 5 -Ile-Lys-Thr 8 -Leu-Leu-NH 2 )-designed (lipo)-peptides, aiming at the development of new antibiotic substances. The design of synthetic compounds based on natural bioactive molecules is an optimistic strategy for the development of new pharmaceutics. Antimicrobial peptides (AMPs) and (lipo)-peptides are two classes of promising compounds, with characteristics that allow them to express their activity by differentiated mechanisms of action. On this basis, anoplin, a natural AMP, was used as a scaffold to design five peptides and seven lipopeptide analogs of them. Substitutions were made on residues Leu 3 and Arg 5 of the interphase and on Thr 8 of the polar phase, as well as N-terminus conjunctions with octanoic and decanoic acid. The outcome of the biological evaluation revealed that some analogs might have substantial clinical potential. Specifically, Ano 1-F, Ano 3-F, Ano 4-C 10 , and Ano 5-F are strongly active against Gram-negative bacteria at minimum inhibitory concentration (MIC) values of 3 μg/ml, while Ano 4-F is active against Gram-positive bacteria at 1 μg/ml. Ano 2-C 10 , C 10 -Gly-Leu-Lys 3 -Lys-Ile 5 -Ile-Lys-Lys 8 -Leu-Leu-NH 2 , is the most promising compound (MIC = 0.5 μg/ml) for the development of new pharmaceutics. The conformational features of the synthetic peptides were investigated by circular dichroism spectroscopy, and their physicochemical parameters were calculated. Our study shows that appropriate substitutions in the anoplin sequence in combination with N α -acylation may lead to new effective AMPs., (© 2021 European Peptide Society and John Wiley & Sons, Ltd.)

Friction stir welding (FSW) offers significant advantages over fusion welding, particularly for high-strength alloys like Inconel 718. However, achieving optimal surface quality in Inconel 718 FSW remains challenging due to its sensitivity to temperature fluctuations during welding. This study integrates finite element simulations, statistical analysis, and advanced control methodologies to enhance weld surface quality through adequate thermal management. High-fidelity simulations of the FSW process were conducted using a validated 3D transient COMSOL Multiphysics model, producing a comprehensive dataset correlating process parameters (rotational speed, axial force, and welding speed) with workpiece temperature. This dataset facilitated statistical analysis and parameter optimization through Analysis of variance (ANOVA) method, leading to a deeper understanding of process variables. A nonlinear state-space system model was subsequently developed using experimental data and the system identification toolbox in Matlab, incorporating domain-specific insights. This model was rigorously validated with an independent dataset to ensure predictive accuracy. Utilizing the validated model, tailored control strategies, including proportional-integral-derivative (PID) and model predictive control (MPC) in both single and multivariable configurations, were designed and evaluated. These control strategies excelled in maintaining welding temperatures within optimal ranges, demonstrating robustness in response times and disturbance handling. This precision in thermal management is poised to significantly refine the FSW process, enhancing both surface integrity and microstructural uniformity. The strategic implementation of these controls is anticipated to substantially improve the quality and consistency of welding outcomes. [ABSTRACT FROM AUTHOR]

Residual stresses and anisotropic structures characterize laser powder bed fusion (L-PBF) products due to rapid thermal changes during fabrication, potentially leading to microcracking and lower strength. Post-heat treatments are crucial for enhancing mechanical properties. Numerous dental technology laboratories worldwide are adopting the new technologies but must invest considerable time and resources to refine them for specific requirements. Our research can assist researchers in identifying thermal processes that enhance the mechanical properties of dental Co-Cr alloys. In this study, high cooling rates (quenching) and annealing after quenching were evaluated for L-PBF Co-Cr dental alloys. Cast samples (standard manufacturing method) were tested as a second reference material. Tensile strength, Vickers hardness, microstructure characterization, and phase identification were performed. Significant differences were found among the L-PBF groups and the cast samples. The lowest tensile strength (707 MPa) and hardness (345 HV) were observed for cast Starbond COS. The highest mechanical properties (1389 MPa, 535 HV) were observed for the samples subjected to the water quenching and reheating methods. XRD analysis revealed that the face-centered cubic (FCC) and hexagonal close-packed (HCP) phases are influenced by the composition and heat treatment. Annealing after quenching improved the microstructure homogeneity and increased the HCP content. L-PBF techniques yielded superior mechanical properties compared to traditional casting methods, offering efficiency and precision. Future research should focus on fatigue properties. [ABSTRACT FROM AUTHOR]

Friction Stir Welding (FSW) has emerged as a prominent technique for joining metallic materials, offering advantages in both similar and dissimilar material combinations. Despite its effectiveness, further advancements are needed to address industry demands and enhance the understanding of the FSW process. Welding nickel-based superalloys like Inconel 718 poses specific challenges, with existing literature suggesting that achieving successful welds requires high axial forces and precise process parameters, limiting its practical application in industries. To tackle these issues, this research proposes the utilization of 3D finite element models integrating multiphysics aspects, encompassing material flow and heat transfer mechanisms such as conduction, convection, and radiation. These models were validated against existing experimental data and employed to analyze temperature and strain distributions within the heat affected zone and weld nugget. The findings offer insights into the impact of various process parameters, including rotational speed, welding speed, normal force, cooling rate, and the effect of induction preheating, on key performance metrics like temperature profiles, grain size distribution, microhardness, and stress evolution. The outcomes underscore a notable correlation between process variables and performance indicators, facilitating a comprehensive understanding of the FSW process dynamics. [ABSTRACT FROM AUTHOR]

Katiki Domokou is a traditional Greek cheese, which has received the Protected Designation of Origin recognition since 1994. Its microfloras have not been studied although its structure and composition may enable (or even favor) the survival and growth of several pathogens, including Listeria monocytogenes. The persistence of L. monocytogenes during storage at different temperatures has been the subject of many studies since temperature abuse of food products is often encountered. In the present study, five strains of L. monocytogenes were aseptically inoculated individually and as a cocktail in Katiki Domokou cheese, which was then stored at 5, 10, 15, and 20 degrees C. Pulsed-field gel electrophoresis was used to monitor strain evolution or persistence during storage at different temperatures in the case of the cocktail inoculum. The results suggested that strain survival of L. monocytogenes was temperature dependent since different strains predominated at different temperatures. Such information is of great importance in risk assessment studies, which typically consider only the presence or absence of the pathogen.

The aim of this study is to investigate the changes of the pupil's light reflex (PLR) and mobility in Parkinson's disease (PD) patients with and without cognitive disorder. Twenty two (22) patients (ten males, twelve females, mean age: 72.7+/-7.3 years) with identified PD entered the study. The patients were examined with the Mini Mental State Examination (MMSE), the Wechsler II Memory Scale (WMS II) and the Hamilton Depression Scale (HAM-D17). Eleven (11) patients (five males, six females, mean age: 72.09+/-7.06 years) were free of any cognitive deficits and eleven (11) patients (five males, six females, mean age: 73.36+/-7.55 years) had cognitive disorder according to the aforementioned scales. None of the patients satisfied the DSM-IV-TR criteria for depression or anxiety disorder. The patients underwent a pupillometric study in both eyes with single flash stimuli of 24.6 candelas/m(2) intensity and 20 ms duration. The pupillometric parameters that were studied were: Latency for the onset of Constriction (T1), Baseline Pupil Radius (R1), Minimum Pupil Radius after the pupil reaction to light (R2), Amplitude (AMP, R1-R2), Time for maximum Miosis (T2), Maximum Constriction Velocity (VCmax) and Maximum Constriction Acceleration (ACmax). The pupillometric findings of each group were compared to those of an age and sex matched group of eleven healthy subjects. Furthermore, a comparison between the findings of the two groups was conducted. ACmax and VCmax were significantly lower in patients without (PD) and with coexisting cognitive impairment (PDC) compared to normal subjects (NC) (p<0.001). Patients with cognitive impairment (PDC) had significantly lower levels of ACmax, VCmax and AMP than patients without cognitive deficits (PD). Cognitive impairment in PD, which mainly reflects a central cholinergic deficit, may be a crucial pathogenetic factor for the decrease in the aforementioned pupillometric parameters. VCmax and ACmax can be considered as the most sensitive indicators of this central cholinergic deficiency.

In the present work, survival of Listeria monocytogenes in the traditional Greek soft, spreadable cheese Katiki was studied throughout the shelf life of the product. Samples of finished cheese were inoculated with a cocktail of five L. monocytogenes strains (ca. 6 log CFU g(-1)) and stored at 5, 10, 15, and 20 degrees C. Acid-stress adaptation or cross-protection to the same stress was also investigated by inoculation of acid-adapted cells in the product. The results showed that pathogen survival was biphasic. Various mathematical equations (Geeraerd, Cerf, Albert-Mafart, Whiting, Zwietering, and Baranyi models) were fitted to the experimental data. A thorough statistical analysis was performed to choose the best model. The Geeraerd model was finally selected, and the results revealed no acid tolerance acquisition (no significant differences, P > 0.05, in the survival rates of the non-acid-adapted and acid-adapted cells). Secondary modeling (second-order polynomial with a(0) = 0.8453, a(1) = -0.0743, and a(2) = 0.0059) of the survival rate (of sensitive population), and other parameters that were similar at all temperatures (fraction of initial population in the major population = 99.98%, survival rate of resistant population = 0.10 day(-1), and initial population = 6.29 log CFU g(-1)), showed that survival of the pathogen was temperature dependent with bacterial cells surviving for a longer period of time at lower temperatures. Finally, the developed predictive model was successfully validated at two independent temperatures (12 and 17 degrees C). This study underlines the usefulness of predictive modeling as a tool for realistic estimation and control of L. monocytogenes risk in food products. Such data are also useful when conducting risk assessment studies.

LEVIS is an innovation project funded by the EU Horizon 2020 program. Its main objective is to develop lightweight multi-material solutions based on bio-based materials and carbon fiber thermoplastic composites for electric vehicle components and demonstrating the technical, operational, and economic feasibility of applying eco-design and circular-economy principles into the design process. The project demonstrates the application of these materials in four case studies: a suspension control arm, a battery box, a battery module housing, and a cross-car beam. All demonstrators achieved a 20%-to-40% reduction in component weight, but environmental assessment results varied significantly, with emissions changes ranging from an increase for suspension control arms to a 65.5% decrease for battery modules. Efficient use of materials, particularly in the battery box using hybrid solutions and bonding technologies, showed notable emissions reduction. In contrast, replacing steel with CFRPs in suspension control arms led to increased emissions, suggesting that CFRPs are more effective for replacing high-polluting materials like aluminum. Recycled carbon fibers proved more beneficial for low-polluting materials like steel. The environmental performance of technologies depends on the expected use of EVs and the electricity grid mix, with better outcomes in coal-reliant grids. Finally, no single recycling method is universally superior; the optimal method depends on the specific technologies and the energy required for recycled materials. [ABSTRACT FROM AUTHOR]

This article discusses the effect of UV-C radiation on two types of cured polymer resins, epoxy and polyester, intended for use in disinfection chambers. The exposure of the samples to UV-C rays lasted 168 h. Our evaluation covered two aspects: the effect of UV-C rays on the flammability and flame retardancy of the resins, and the effect of UV-C rays on the adhesion of the resins to the steel substrate. It was found that the applied halogen and halogen-free organophosphate agents can be used for the tested resins under UV-C conditions (e.g. disinfection chambers), and no negative impact of UV-C radiation on the performance of these flame retardants was found. The use of the tested types of resins in the form of thin coatings on a steel substrate is feasible in disinfection chambers under UV-C radiation conditions, as the obtained results indicate that the radiation did not affect the adhesion of the coating. The visible effect of UV-C radiation on both the tested resins was discoloration, giving yellow and brown colors. Our results suggest that further studies, probably involving longer UV-C exposure, would be advisable. [ABSTRACT FROM AUTHOR]

Easily applied diagnostic tools such as digital biomarkers for Alzheimer's disease (AD) are urgently needed due to the recent approval of disease‐modifying therapies. We aimed to determine the diagnostic performance of hand‐held, quantitative light reflex pupillometry (qLRP) in patients with AD in a proof‐of‐concept, cross‐sectional study. Participants underwent qLRP at a university memory clinic from August 2022 to October 2023. We fitted multivariable logistic regression models with qLRP, sex, and age as predictors evaluated with area under the receiver operating characteristics curve (AUROC). In total, 107 patients with AD, 44 patients with mixed AD and vascular cognitive dysfunction (VCD), 53 patients with dementia with Lewy bodies (DLB), and 50 healthy controls (HCs) were included. Our diagnostic models showed similar discriminatory ability (AUROC range 0.74‐0.81) when distinguishing patients with AD from HCs and other dementias. The qLRP seems promising as a bedside digital biomarker to aid in diagnosing AD. Highlights: We demonstrated the diagnostic performance of qLRP in Alzheimer's disease.The diagnostic models were robust in sensitivity analyses.qLRP may assist in the bedside diagnostic evaluation of Alzheimer's disease. [ABSTRACT FROM AUTHOR]

Atypical antipsychotics, including olanzapine, were originally expected to reduce the risk of haematological toxicity and to be safe alternatives to clozapine. We report a case of patient who developed leucopenia and neutropenia during treatment with olanzapine.

Two mixed-valence Mn(III)Mn(II) complexes and a homo-valence Mn(II) trinuclear manganese complex of stoichiometry Mn(III)Mn(II)Mn(III)(5-Cl-Hsaladhp)(2)(AcO)(4)(MeOH)(2).4CH(3)OH (1a), Mn(III)Mn(II)Mn(III) (Hsaladhp)(2)(AcO)(2)(5-Cl-Sal)(2)(thf)(2) (3a) and Mn(II)Mn(II)Mn(II) (AcO)(6)(pybim)(2) (1b) where H(3)saladhp is a tridentate Schiff base ligand and pybim a neutral bidentate donor ligand, have been structurally characterized by using X-ray crystallography. The structurally characterized mixed-valence complexes have strictly 180 degrees Mn(III)-Mn(II)-Mn(III) angles as required by crystallographic inversion symmetry. The complexes are valence trapped with two terminal Mn(III) ions showing Jahn-Teller distortion along the acetate or salicylate-Mn(III)-X axis. The Mn.Mn separation is 3.511 Å and 3.507 Å respectively. The mixed-valence complexes have S = (3)/(2) ground state and the homovalence complex S = (5)/(2), with small antiferromagnetic exchange J couplings, -5.6 and -1.8 cm(-1), respectively, while the powder ESR spectra at 4 K show a broad low field signal with g approximately 4.3 for Mn(III)Mn(II)Mn(III) and a broad temperature-dependent signal at g = 2 for Mn(II)Mn(II)Mn(II). Crystal data for 1a: [C(36)H(60)O(20)N(2)Cl(2)Mn(3)], triclinic, space group P&onemacr;, a = 9.272(7) Å, b = 11.046(8) Å, c = 12.635(9) Å, alpha = 76.78(2) degrees, beta = 81.84(2) degrees, gamma = 85.90(2) degrees, Z = 1. Crystal data for 3a: [C(48)H(56)O(18)N(2)Cl(2)Mn(3)], monoclinic, space group P2(1)/n, a = 8.776(3) Å, b = 22.182(7) Å, c = 13.575(4) Å, beta = 94.44(1) degrees, Z = 2. Crystal data for 1b: [C(36)H(36)O(12)N(6)Mn(3)], triclinic, space group P&onemacr;, a = 13.345(6) Å, b = 8.514(4) Å, c = 9.494(4) Å, alpha = 75.48(1) degrees, beta = 75.83(1) degrees, gamma = 76.42(1) degrees, Z = 1.

In this paper, Al-Mg-Si alloys with a thickness of 4 mm are welded by using laser beam welding (LBW) and laser-MIG hybrid welding, respectively, and the microstructure and mechanical properties of the two joints are investigated. The results show that the fusion zone (FZ) of the two joints is composed of columnar crystal and equiaxed dendrite grain, and its main constituent phases are an α-Al matrix phase and a β(Mg2Si) strengthening phase. In the case of similar heat inputs, compared with those of the LBW joint, the grain size in the laser-MIG hybrid joint is smaller and there are more second phases such as the β phase in the FZ, which is related to the different action mechanisms on the base metal (BM) by the two welding processes. Under the three strengthening mechanisms of fine grain strengthening, precipitation strengthening, and solid solution strengthening, the laser-MIG hybrid welding joint shows better mechanical properties than that of the LBW joint. The maximum tensile strength of the LBW joint and the laser-MIG hybrid joint is 202 MPa and 253 MPa, respectively, and the elongation is 3.8% and 5.1%, respectively. [ABSTRACT FROM AUTHOR]

Food safety incidents caused by bacterial contamination have always been one of the public safety issues of social concern. Planktonic cells, viable but non‐culturable (VBNC) cells, and biofilm cells of bacteria can coexist in food or food processing, posing more serious challenges to public health and safety by increasing bacterial survival and difficulty in detection. As a non‐toxic, no side effect, and highly effective bacteriostatic substance, nisin has received wide attention from researchers. In this review, we summarized the species and biosynthesis of nisin, the effects of nisin alone or in combination with other treatments on planktonic and biofilm cells, and its applications in the fields of food, feed, and medicine by consulting numerous studies. Meanwhile, the mechanism of nisin on planktonic and biofilm cells was proposed based on existing researches. Nisin not only has antibacterial activity against most G+ bacteria but also exhibits a bacteriostatic effect on G− bacteria when combined with other antibacterial treatments. In addition to planktonic cells, nisin also has significant effects on bacterial cells in biofilms by changing the thickness, density, and composition of biofilms. Based on the three action processes of nisin on biofilms, we summarized the changes of bacteria in biofilms, including the causes of bacterial death and the formation of the VBNC state. We consider that research on the relationship between nisin and VBNC state should be strengthened. [ABSTRACT FROM AUTHOR]