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Objective: To investigate Covid-19 vaccine hesitancy among Iraqi healthcare workers-HCWs. Study design: Cross-sectional survey. Methods: In February 2021, an anonymous questionnaire on the willingness of receiving Covid-19 vaccination was submitted to a sample of HWCs in the Dohuk Governorate, Iraqi Kurdistan Region. Overall, 1704 questionnaires were analysed by means of univariate and multivariate statistics. Results: The sample included 978 males and 726 females (Mean age: 36.9 ± 10.1), working in Primary Health Centres (65.8%) or in Public Hospitals (34.2%). Professions ranged from being physician/paramedics (39.3%) to administrative/laboratory staff (31.7%); 17.0% had attended up to secondary school, the rest had a higher education. Considering health conditions, 1.8% reported a poor health status and 11.5% a chronic disease.Overall, 475 people (27.9%) reported Covid-19 vaccine hesitancy, with fear of side-effects (41.4%) and lack of confidence in using the vaccine (23.5%) being the most common perceived barriers. Midwifes (61.1%) and assistant nurses (45.5%) were the most hesitant; physicians the less (12.3%). According to a binary logistic model, holding lower educational level (adjOR = 2.158; 95% CI:1.654–2.815), being female (adjOR = 1.622; 95% CI:1.289–2.040), having pre-existing chronic disease (adjOR = 1.954; 95% CI:1.280–2.983), and self-perceiving a poor health status (adjOR = 3.673; 95% CI:1.610–8.379) were independent predictors of higher odds of hesitancy. Conclusion: Covid-19 vaccine hesitancy among HCWs represents an important public health concern, since they play a paramount role for a successful vaccination campaign within the community. Our results show the need in Iraq to implement educational interventions for strengthening the confidence of HWCs towards the Covid-19 vaccine, therefore positively influencing the general public's attitude.

This paper addresses the active control of mechanical vibrations induced in laminated composite doubly curved shells. A three dimensional energy based finite element model has been developed for this analysis. The laminated shell is integrated with a patch of active constrained layer damping (ACLD) treatment in which vertically reinforced 1-3 piezoelectric composite is used as the material of the constraining layer. Both in-plane and out-of-plane actuations of the constraining layer of the ACLD treatment have been utilized for deriving the finite element model. Investigation has been carried out to see the performance of the patch when the orientation angle of the piezoelectric fibers of the constraining layer is varied in the two mutually orthogonal vertical planes. The analysis revealed that the vertically reinforced 1-3 piezoelectric composites which are in general being used for the distributed sensors can be potentially used for the distributed actuators of high performance light-weight smart composite shells. [ABSTRACT FROM AUTHOR]

Measuring the viscosity of pharmaceutical dosage forms is a crucial process. Viscosity provides information about the stability of the composition, the release rate of the drug, bioavailability, and, in the case of injectable drug formulations, even the force required for injection. However, measuring viscosity is a complex task with numerous challenges, especially for non-Newtonian materials, which include most pharmaceutical formulations, such as gels. Selecting the appropriate shear rate is critical. Since viscosity in many systems is highly temperature-dependent, stable temperature control is necessary during the measurement. Using microfluidics technology, it is now possible to perform rheological characterization and conduct fast and accurate measurements. Small sample volumes (even below 500 µL) are required, and viscosity determination can be carried out over a wide range of shear rates. Nevertheless, the pharmaceutical application of viscometers operating on the principle of microfluidics is not yet widespread. In our work, we compare the results of measurements taken with a microfluidic chip-based viscometer on different pharmaceutical forms (gels, solution) with those obtained using a traditional rotational viscometer, evaluating the relative advantages and disadvantages of the different methods. The microfluidics-based method enables time- and sample-efficient viscosity analysis of the examined pharmaceutical forms.

Microparticles have unique benefits in the formulation of multiparticulate and multi-unit type pharmaceutical dosage forms allowing improved drug safety and efficacy with favorable pharmacokinetics and patient centricity. On the other hand, the above advantages are served by high and well reproducible quality attributes of the medicinal product where even flexible design and controlled processability offer success as well as possible longer product life-cycle for the manufacturers. Moreover, the specific demands of patients can be taken into account, including simplified dosing regimens, flexible dosage, drug combinations, palatability, and ease of swallowing. In the more than 70 years since the first modified-release formulation appeared on the market, many new formulations have been marketed and many publications have appeared in the literature. More unique and newer pharmaceutical technologies and excipients have become available for producing tailor-made particles with micrometer dimensions and beyond. All these have contributed to the fact that the sub-units (e.g. minitablets, pellets, microspheres) that make up a multiparticulate system can vary widely in composition and properties. Some units have mucoadhesive properties and others can float to contribute to a suitable release profile that can be designed for the multiparticulate formula as a whole. Nowadays, there are some available formulations on the market, which are able to release the active substance even for several months (3 or 6 months depending on the type of treatment). In this review, the latest developments in technologies that have been used for a long time are presented, as well as innovative solutions such as the applicability of 3D printing to produce subunits of multiparticulate systems. Furthermore, the diversity of multiparticulate systems, different routes of administration are also presented, touching the ones which are capable of carrying the active substance as well as the relevant, commercially available multiparticle-based medical devices. The versatility in size from 1 µm and multiplicity of formulation technologies promise a solid foundation for the future applications of dosage form design and development., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Self-assembling peptides are attractive alternatives in the field of biomaterial science due to their variability and biocompatibility. Unfortunately, such peptides have poor solubility, and their purification, synthesis, and overall handling are challenging. Our main objective was to develop a cage peptide design with full control over self-assembly. Theoretically, aggregation can be suppressed by temporally masking the amino acid side chains at critical positions. Taking into account several biological and synthetic requirements, a photosensitive protecting group, p -hydroxy-phenacyl (pHP), was chosen as the "masking" moiety. To test our theory, EAK16-II was chosen as a model self-assembling peptide, and a caged derivative containing photosensitive pHP groups was synthesized. Both spectroscopic and in vitro experiments on A2058 melanoma cells confirmed our hypothesis that the caged-EAK16-II peptide has good solubility and that the hydrogel formed after photolysis results in similar viability and cell aggregate formation of melanoma cells as the native EAK16-II-based hydrogel., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

A significant proportion of pharmaceuticals are now considered multiparticulate systems. Modified-release drug delivery formulations can be designed with engineering precision, and patient-centric dosing can be accomplished relatively easily using multi-unit systems. In many cases, Multiple-Unit Pellet Systems (MUPS) are formulated on the basis of a neutral excipient core which may carry the layered drug surrounded also by functional coating. In the present summary, commonly used starter pellets are presented. The manuscript describes the main properties of the various nuclei related to their micro- and macrostructure. In the case of layered pellets formed based on different inert pellet cores, the drug release mechanism can be expected in detail. Finally, the authors would like to prove the industrial significance of inert cores by presenting some of the commercially available formulations.

The presence of additive manufacturing, especially 3D printing, has the potential to revolutionize pharmaceutical manufacturing owing to the distinctive capabilities of personalized pharmaceutical manufacturing. This study's aim was to examine the behavior of commonly used polyvinyl alcohol (PVA) under in vitro dissolution conditions. Polylactic acid (PLA) was also used as a comparator. The carriers were designed and fabricated using computer-aided design (CAD). After printing the containers, the behavior of PVA under in vitro simulated biorelevant conditions was monitored by gravimetry and dynamic light scattering (DLS) methods. The results show that in all the dissolution media PVA carriers were dissolved; the particle size was under 300 nm. However, the dissolution rate was different in various dissolution media. In addition to studying the PVA, as drug delivery carriers, the kinetics of drug release were investigated. These dissolution test results accompanied with UV spectrophotometry tracking indirectly determine the possibilities for modifying the output of quality by computer design.

Electrospun nanofibers have a wide range of applications due to their unique miniature size and accompanying ultra-high specific surface area. Polyvinyl alcohol(PVA) is a kind of hydrophilic materials, and hence its nanofiber morphology prepared by electrospinning disappeared after solution immersing. In the present work, crosslinked PVA nanofibers were prepared by electrospinning and then employing glutaraldehyde vapor crosslinking to improve their water resistance and mechanical properties. As an application, these nanofibers were used to adsorb Cu 2+ and Pb 2+ according to varying crosslinking time and different concentrations of ionic solution. It was observed the crosslinked PVA nanofiber films maintained good fiber morphology after adsorption, while the nanofiber morphology of uncrosslinked samples was lost. The stability of the crosslinked nanofiber films in water was improved, the adsorption equilibrium time of Pb 2+ decreased from 30 h to 10 h while the equilibrium adsorption time of Cu 2+ decreased from 15 h to 5 h, and the tensile strength of the nanofiber films with crosslinking time of 20 h was 7.99 MPa, which was 240% higher than that of the nanofiber with crosslinking time of 1 h, indicating higher efficiency., (Copyright © 2019. Published by Elsevier B.V.)

As experimental probes have matured to observe ultrafast transient and high frequency responses of materials and devices, so to have the theoretical methods to numerically and analytically simulate time- and frequency-resolved transport. In this review article, we discuss recent progress in the development of the time-dependent and frequency-dependent non-equilibrium Green function (NEGF) technique. We begin with an overview of the theoretical underpinnings of the underlying Kadanoff-Baym equations and derive the fundamental NEGF equations in the time and frequency domains. We discuss how these methods have been applied to a variety of condensed matter systems such as molecular electronics, nanoscale transistors, and superconductors. In addition, we survey the application of NEGF in fields beyond condensed matter, where it has been used to study thermalization in ultra-cold atoms and to understand leptogenesis in the early universe. Throughout, we pay special attention to the challenges of incorporating contacts and interactions, as the NEGF method is uniquely capable of accounting for such features.

Chloroplasts contain 80-90% of iron taken up by plant cells. Though some iron transport-related envelope proteins were identified recently, the mechanism of iron uptake into chloroplasts remained unresolved. To shed more light on the process of chloroplast iron uptake, trials were performed with isolated intact chloroplasts of sugar beet (Beta vulgaris). Iron uptake was followed by measuring the iron content of chloroplasts in the form of ferrous-bathophenantroline-disulphonate complex after solubilising the chloroplasts in reducing environment. Ferric citrate was preferred to ferrous citrate as substrate for chloroplasts. Strong dependency of ferric citrate uptake on photosynthetic electron transport activity suggests that ferric chelate reductase uses NADPH, and is localised in the inner envelope membrane. The K(m) for iron uptake from ferric-citrate pool was 14.65 ± 3.13 μM Fe((III))-citrate. The relatively fast incorporation of (57)Fe isotope into Fe-S clusters/heme, detected by Mössbauer spectroscopy, showed the efficiency of the biosynthetic machinery of these cofactors in isolated chloroplasts. The negative correlation between the chloroplast iron concentration and the rate of iron uptake refers to a strong feedback regulation of the uptake., (Copyright © 2011 Elsevier Masson SAS. All rights reserved.)

In plants, Cd causes perturbation of root metal uptake and is known to interfere with the metal translocation to the shoot. The most significant effect is the strongly reduced transport of Fe. Fe accumulation in roots under Cd stress revealed that it is not the Fe acquisition but the Fe loading to xylem elements that is blocked by Cd, which can be a result of competition between Fe and Cd for the transporters. However, in animal cells as well as in plant stomata guard cells, Cd was shown to move through Ca channels. To clarify whether the perturbation of metal translocation/xylem loading caused by Cd show any regularity, translocation ability was tested by the determination of the metal content in leaves of hydroponically cultured (¼ Hoagland nutrient solution, Fe source: 10 μM Fe((III))-citrate) poplar plants grown for three weeks with or without 10 μM Cd(NO₃)₂ treatment. Metals could be classified into two groups according to the behavior of their translocation under Cd treatment: alkaline earth metals (except Mg), Zn and Mn were influenced similarly to Ca, but other transition metals (together with alkali metals and Al) behaved like the Fe. Based on the translocation pattern, Cd seems to inhibit the transport of Ca-like metals competitively, but a different type of inhibition is exerted on the transition metal transport, with which Cd can share a common translocation system. The strongly decreased translocation of chelator-dependent transition metals may indicate Cd related disturbances in signalling pathways and gene expression of xylem transporters or chelators., (Copyright © 2011 Elsevier Masson SAS. All rights reserved.)

Cadmium interference with Fe nutrition has a strong impact on the development and efficiency of the photosynthetic apparatus. To shed more light on the interaction between Fe and Cd, it was studied how iron given in moderate excess under Cd stress affects the development and functioning of chlorophyll-protein complexes. Poplar plants grown in hydroponics up to four-leaf stage were treated with 10 μM Cd(NO₃)₂ in the presence of 50 μM Fe([III])-citrate as iron supply (5xFe + Cad) for two weeks. Though leaf area growth was inhibited similarly to that of Cad (10 μM Cd(NO₃)₂ + 10 μM Fe([III])-citrate) plants, chlorophyll content, ¹⁴CO₂ fixation and quenching parameters calculated from PAM fluorescence induction measurements were control-like in 5xFe+Cad leaves. Increased chloroplast iron content (measured photometrically by the bathophenanthroline disulfonate method) without changes in the iron and cadmium content of leaves (determined by inductively coupled plasma mass spectrometry) pointed out that a key factor in the observed protection of photosynthesis is the iron-excess-induced redistribution of iron in the leaf. However, the chlorophyll a/b ratio and the chlorophyll-protein pattern obtained by Deriphat PAGE remained similar to that of Cad leaves. The decreased amount of PSII core and PSI in mature and developing leaves, respectively, refers to developmental stage-dependent remodelling of thylakoids in the presence of Cd. The results underline not only the beneficial effect of iron excess under Cd stress, but also refer to the importance of a proper Fe/Cd ratio and light environment to avoid its possible harmful effects., (Copyright © 2011 Elsevier Masson SAS. All rights reserved.)

Real-time RT-PCR is currently the most sensitive, specific and precise approach to analyse gene expression changes in plant stress studies. The determination of biologically meaningful transcript quantities requires accurate normalisation of the raw data. During relative quantification the reliability of the results depends on the stable expression of the endogenous control genes across the experimental samples. Four widely used internal control genes (cyclophilin, elongation factor 1α, polyubiquitin, tubulin β-chain) and two potential candidates (serine/threonine-protein phosphatase 2A and ubiquitin-conjugating enzyme) genes were assessed under Cd-stress and at different developmental stages in leaves of Populus jacquemontiana D. var. glauca H. Complementary DNA (RiboGreen) based quantification method revealed variations in the expression level of reference genes. The variability was more pronounced under severe stress conditions. Less variation was observed in the case of ef-1α, pp2a and ubc10. Transcript level changes of a target gene, psa-h, was also evaluated by two independent normalisation strategies, by the RiboGreen method or by using multiple references. The impact of variability of reference gene on the target gene evaluation was demonstrated. It was proved that in the absence of suitable housekeeping genes, for example under severe stress, RiboGreen method is convenient tool for transcript normalisation.