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We report the effects of Ba, Ti, and Mn dopants on ferroelectric polarization and leakage current of (K0.44Na0.52Li0.04)(Nb0.84Ta0.1Sb0.06)O3 (KNN-LT-LS) thin films deposited by pulsed laser deposition. It is shown that donor dopants such as Ba2+, which increased the resistivity in bulk KNN-LT-LS, had an opposite effect in the thin film. Ti4+ as an acceptor B-site dopant reduces the leakage current by an order of magnitude, while the polarization values showed a slight degradation. Mn4+, however, was found to effectively suppress the leakage current by over two orders of magnitude while enhancing the polarization, with 15 and 23 μC/cm2 remanent and saturated polarization, whose values are ∼70% and 82% of the reported values for bulk composition. This phenomenon has been associated with the dual effect of Mn4+ in KNN-LT-LS thin film, by substituting both A- and B-site cations. A detailed description on how each dopant affects the concentrations of vacancies in the lattice is presented. Mn-doped KNN-LT-LS thin films are shown to be a promising candidate for lead-free thin films and applications. [ABSTRACT FROM AUTHOR]

We report the growth of single-phase (K0.44,Na0.52,Li0.04)(Nb0.84,Ta0.10,Sb0.06)O3 thin films on SrRuO3 coated <001> oriented SrTiO3 substrates by using pulsed laser deposition. Films grown at 600 °C under low laser fluence exhibit a <001> textured columnar grained nanostructure, which coalesce with increasing deposition temperature, leading to a uniform fully epitaxial highly stoichiometric film at 750 °C. However, films deposited at lower temperatures exhibit compositional fluctuations as verified by Rutherford backscattering spectroscopy. The epitaxial films of 400–600 nm thickness have a room temperature relative permittivity of ∼750 and a loss tangent of ∼6% at 1 kHz. The room temperature remnant polarization of the films is 4 μC/cm2, while the saturation polarization is 7.1 μC/cm2 at 24 kV/cm and the coercive field is ∼7.3 kV/cm. The results indicate that approximately 50% of the bulk permittivity and 20% of bulk spontaneous polarization can be retained in submicron epitaxial KNN-LT-LS thin film, respectively. The conductivity of the films remains to be a challenge as evidenced by the high loss tangent, leakage currents, and broad hysteresis loops. [ABSTRACT FROM AUTHOR]

The effects of Ba, Ti and Mn dopants on ferroelectric polarization and leakage current of ([K.sub.0.44][Na.sub.0.52][Li.sub.0.04])([Nb.sub.0.84][Ta.sub.0.1][Sb.sub.0.06])[O.sub.3] (KNN-LT-LS) thin films deposited by pulsed laser deposition are examined. The effects of dopants on the concentrations of vacancies in the lattice are described and Mn-doped KNN-LT-LS thin films are used for lead-free thin films.

A pulsed laser deposition technique was used to study the growth of single-phase ([K.sub.0.44], [Na.sub.0.52], [Li.sub.0.04])([Nb.sub.0.84], [Ta.sub.0.10], [Sb.sub.0.06])[O.sub.3] thin films on SrRu[O.sub.3] coated (001) oriented SrTi[O.sub.3] substrates. The results showed that the thickness of KNN-LT-LS films could be pulled below 1000 nm while retaining 22% of the bulk remnant polarization and the conductivity problem could be controlled by donor doping such as [Ba.sup.2+] and manganese.

Conduction mechanisms in epitaxial (001)-oriented pure and 1 mol % Mn-doped (K0.44,Na0.52,Li0.04)(Nb0.84,Ta0.1,Sb0.06)O3 (KNN-LT-LS) thin films on SrTiO3 substrate were investigated. Temperature dependence of leakage current density was measured as a function of applied electric field in the range of 200-380 K. It was shown that the different transport mechanisms dominate in pure and Mn-doped thin films. In pure (KNN-LT-LS) thin films, Poole-Frenkel emission was found to be responsible for the leakage, while Schottky emission was the dominant mechanism in Mn-doped thin films at higher electric fields. This is a remarkable yet clear indication of effect of 1 mol % Mn on the resistive behavior of such thin films. [ABSTRACT FROM AUTHOR]

Dielectric and piezoelectric properties of morphotropic phase boundary (Bi,Na)TiO3–(Bi,K)TiO3–BaTiO3 epitaxial thin films deposited on SrRuO3 coated SrTiO3 substrates were reported. Thin films of 350 nm thickness exhibited small signal dielectric permittivity and loss tangent values of 750 and 0.15, respectively, at 1 kHz. Ferroelectric hysteresis measurements indicated a remanent polarization value of 30 μC/cm2 with a coercive field of 85–100 kV/cm. The thin film transverse piezoelectric coefficient (e31,f) of these films after poling at 600 kV/cm was found to be -2.2 C/m2. The results indicate that these BNT-based thin films are a potential candidate for lead-free piezoelectric devices. [ABSTRACT FROM AUTHOR]

Oxygen partial pressure (PO2) in pulsed laser deposition significantly influences the composition, microstructure, and electrical properties of epitaxial misfit strain-relieved 450 nm <001> oriented epitaxial (K0.44,Na0.52,Li0.04)(Nb0.84,Ta0.10,Sb0.06)O3 thin films on SrRuO3 coated SrTiO3. Films deposited at 400 mTorr exhibit high remnant and saturated polarization of 7.5 and 16.5 μC/cm2, respectively, which is ∼100% increase over the ones grown at 100 mTorr. The dielectric constant linearly increases from 220 to 450 with increasing PO2. The observed changes in surface morphology of the films and their properties are shown to be due to the suppression of volatile A-site cation loss. [ABSTRACT FROM AUTHOR]

Oxygen partial pressure (PO2) in pulsed laser deposition significantly influences the composition, microstructure, and electrical properties of epitaxial misfit strain-relieved 450 nm <001> oriented epitaxial (K0.44,Na0.52,Li0.04)(Nb0.84,Ta0.10,Sb0.06)O3 thin films on SrRuO3 coated SrTiO3. Films deposited at 400 mTorr exhibit high remnant and saturated polarization of 7.5 and 16.5 μC/cm2, respectively, which is ∼100% increase over the ones grown at 100 mTorr. The dielectric constant linearly increases from 220 to 450 with increasing PO2. The observed changes in surface morphology of the films and their properties are shown to be due to the suppression of volatile A-site cation loss. [ABSTRACT FROM AUTHOR]

Single phase, epitaxial, <001> oriented, undoped and 1 mol % Mn-doped (K0.44,Na0.52,Li0.04)(Nb0.84,Ta0.10,Sb0.06)O3 thin films of 400 nm thickness were synthesized on SrRuO3 coated SrTiO3. Such films exhibit well saturated hysteresis loops and have a spontaneous polarization (Ps) of 10 μC/cm2, which is a 150% higher over the Ps of the undoped composition. The coercive field of 1 mol % Mn doped films is 13 kV/cm. Mn-doping results in three orders of magnitude decrease in leakage current above 50 kV/cm electric field, which we attribute to the suppression of intrinsic p-type conductivity of undoped films by Mn donors. [ABSTRACT FROM AUTHOR]

Single phase, epitaxial, <001> oriented, undoped and 1 mol % Mn-doped (K0.44,Na0.52,Li0.04)(Nb0.84,Ta0.10,Sb0.06)O3 thin films of 400 nm thickness were synthesized on SrRuO3 coated SrTiO3. Such films exhibit well saturated hysteresis loops and have a spontaneous polarization (Ps) of 10 μC/cm2, which is a 150% higher over the Ps of the undoped composition. The coercive field of 1 mol % Mn doped films is 13 kV/cm. Mn-doping results in three orders of magnitude decrease in leakage current above 50 kV/cm electric field, which we attribute to the suppression of intrinsic p-type conductivity of undoped films by Mn donors. [ABSTRACT FROM AUTHOR]

We study the temperature dependence of dielectric constant (K) and spontaneous polarization (Ps) in the range of -95–200 °C. Cubic (C)-tetragonal (T) and T-orthorhombic (O) transitions are observed at 264 and 25 °C, respectively. The Curie–Weiss temperature of C-T transition is 249 °C, indicating it is first order. X-ray data indicate T-O phase coexistence at 25 °C. A singularity in Ps at 25 °C and a T-O phase coexistence spanning 25–31 °C was observed, wherein Ps increases from 17×10-2 C/m2 at 31 °C to 23×10-2 C/m2 25 °C. The transition at 25 °C appears diffusionless and polymorphic with martensite start and finish temperatures of 31 and 25 °C, respectively. The maximum in d33 is 345 pC/N and is attributed to the instability at 25 °C, where Ps and K show singularity. [ABSTRACT FROM AUTHOR]

Diabetes Mellitus (DM) disrupts the body's capability to control blood glucose statuses. Type 1 diabetes mellitus (T1DM) arises from inadequate insulin production and is treated with insulin replacement therapy. Stem cell therapy is a hopeful treatment for T1DM that involves using adult stem cells to generate insulin-producing cells (IPCs). Mesenchymal stem cells (MSCs) are particularly advantageous for generating IPCs. The islet cells require interactions with the extracellular matrix for survival, which is lacking in conventional 2D culture systems. Natural or synthetic polymers create a supportive 3D microenvironment in tissue engineering. We aim to construct superior differentiation conditions employing polyethersulfone (PES)/Fish gelatin scaffolds to differentiate Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) to IPCs. In this study, the PES/fish gelatin scaffold (3D) was manufactured by electrospinning, and then its biocompatibility and non-toxicity were investigated by MTT assay. After that, scaffold-supportive effects on WJ-MSCs differentiation to IPCs were studied at the gene and protein levels. After exposure to the differentiation media, 2D and 3D (PES/Fish gelatin) cultured cells were slowly aggregated and developed spherical-shaped clusters. The viability of cells was found to be comparable in both 2D and 3D cultures. The gene expression analysis showed that efficiency of differentiation was more elevated in 3D culture. Additionally, ELISA results indicated that C-peptide and insulin release were more significant in 3D than in 2D culture. In conclusion, the PES/fish gelatin scaffold is highly promising for pancreatic tissue engineering because it supports the viability, growth, and differentiation of WJ-MSCs into IPCs., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Author(s). Published by Elsevier BV on behalf of The Japanese Society for Regenerative Medicine.)

Skin injuries are a global healthcare problem. Chronic ulcers do not heal in a timely fashion, so it is essential to help the body with skin repair. There are some treatments that have been applied to chronic ulcers. One of these treatments is growth factor (GF) therapy. Platelet-rich plasma (PRP) and Platelet-poor plasma (PPP) are two types of plasma derivatives containing many GFs important for wound healing. Several works have reported their application in wound healing and tissue regeneration. The use of autologous PRP is now an adequate alternative in regenerative medicine. It was also demonstrated that PPP is a hemostatic agent for wounds. This review has studied the latest clinical studies, which have applied PRP and PPP to patients with chronic wounds., Competing Interests: The authors have no conflicts of interest to declare., (© 2024 The Japanese Society for Regenerative Medicine. Production and hosting by Elsevier B.V.)

Background: Head lice are a main public health problem and the most important human ectoparasites and the use of pediculicides is the most common way to control it. One of the possible causes of treatment failure is the lack of improper application of pediculicide. The aim of this study was to assess the effect of education on efficacy of 1% permethrin or 4% dimeticone lotion to treat head lice infestation., Methods: This quasi-experimental study included 100 individuals with head lice infestation from comprehensive urban health centers in Ardabil as the intervention group, and 400 individuals from East Azerbaijan and West Azerbaijan provinces as the control group, from April to March 2019. The data collection tools included a demographic questionnaire and an examination recording sheet, which documented the presence of adult lice or nits. Due to the inability to perform random assignment and control for numerous observed covariates, propensity score matching (PSM) was used., Results: The outcome of treatment included elimination of head lice infestation on is 7, and in the case of recurrence, it was considered on days 14 and 30 after treatment. The results showed that the educational intervention program had a significant positive effect on the efficacy of both treatments. The likelihood of improvement was approximately three times greater in the intervention group compared to the control group., Conclusion: Participants who received the training intervention (OR = 3.29; CI 95%: 2.21-4.88) were more likely to have a successful treatment than control group. In the case of providing proper training on the use of pediculicides and observing hygiene tips to patients with pediculosis, could help to successful treatment of pediculosis., (© 2024. The Author(s).)

Background: Women with breast cancer usually face multiple short-term and long-term problems in dealing with their acute and chronic symptoms during and after cancer treatment. However, serious gaps remain in addressing these issues in clinical and public health practice., Methods: According to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines, we conducted a systematic literature search from 2000-2021 in electronic databases, including Medline, PubMed, Embase, Scopus, Web of Knowledge, and Google Scholar databases using predefined keywords., Results: The review identified several significant and interconnected problems in breast cancer patient's treatment and supportive care. The results revealed that these issues are very common among breast cancer patients, and specific attention and serious measures are needed to address these problems. Despite implementing different protocols and programs for covering and addressing these problems, serious gaps still exist in supporting breast cancer patients during clinical and follow-up care., Conclusion: Developing innovative and holistic approaches and programs based on the multifactorial assessment of symptoms are suggested for addressing and covering the multidimensional requirements of this population. Consequently, thorough evaluation, education, treatment, and referrals should be provided for the most common sequelae of these patients by including appropriate medication, exercise, counselling, occupational therapy, and complementary therapies. The present study provides a more comprehensive source of information about breast cancer patient's medical and supportive needs in comparison with individual studies on symptom experiences., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

In the present study, 5-fluorouracil-loaded niosomal nanoparticles were successfully prepared and coated with chitosan and subsequently crosslinked by tripolyphosphate to form niosomal nanogels. The prepared niosomal formulations were fully characterized for their particle size, zeta potential, particle morphology, drug entrapment efficiency, and in vitro drug release profile. The prepared niosomal nanocarriers exhibited nanoscale particle sizes of 165.35 ± 2.75-322.85 ± 2.75 nm. Chitosan-coated and TPP-crosslinked niosomes exhibited a slightly decreased in particle size and a switch of zeta potential from negative to positive values. In addition, high yield percentage, drug encapsulation efficiency, and drug loading values of 92.11 ± 2.07 %, 66.59 ± 6.06, and 4.65 ± 0.5 were obtained for chitosan-coated formulations, respectively. Moreover, lowering the rate of 5-FU in vitro release was achieved within 72 h by using chitosan-coated formulations. All prepared formulations revealed hemocompatible properties in hemolysis assay with less than 5 % hemolysis percentage at their higher possible concentrations (500 µM and 1 mM). The cell viability by MTT assay showed higher anticancer activity against B16F10 cancerous cells and lower cytotoxicity toward NIH3T3 normal cells than control and pure 5-FU in the studied concentration range (10-100 µM). Investigating the cell migration inhibition properties of fabricated formulations revealed similar results with in vitro cell viability assay with a higher migration inhibition rate for B16F10 cells than NIH3T3 cells, controls, and free 5-FU., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Recently, wearing facemasks in public has been raised due to the coronavirus disease 2019 epidemic worldwide. However, the performance and effectiveness of many existing products have raised significant concerns among people and professionals. Therefore, greater attempts have been focused recently to increase the efficacy of these products scientifically and industrially. In this respect, doping or impregnating facemask fabrics with metallic substances or nanoparticles like silver nanoparticles has been proposed. So, in the present study, we aimed to sonochemically coat silver nanoparticles on the non-woven Spunbond substrates at different sonication times and concentrations to develop antibacterial and antiviral facemask. The coated substrates were characterized using Field Emission Scanning Electron Microscope, Energy Dispersive X-Ray, X-ray diffraction, and Thermogravimetry analysis. The amount of silver released from the coated substrates was measured by atomic absorption spectroscopy. The filtration efficiency, pressure drop, and electrical conductivity of the coated samples were also investigated. The antibacterial activity of fabrics was evaluated against Escherichia coli and Staphylococcus aureus. Cellular viability of samples assessed by MTT and brine shrimp lethality tests. The results revealed that the higher sonication times and precursor concentrations result in a higher and more stable coating, larger particle size, wider particle size distribution, and lower content of released silver. Coated fabrics also revealed enhanced filtration efficiency (against nanosize particles), desired pressure drop, and antibacterial activity without significant cytotoxicity toward HEK 293 cells and Artemia nauplii. As a result, the coated fabrics could find potential applications in the development of facemasks for protection against different pathogenic entities., (© 2023. The Author(s).)

Development of an ideal wound dressing with effective function for healing various types of wounds is the ultimate desire of the researchers. Natural-based compounds such as polysaccharides and phytochemicals offer useful properties making them perfect candidates for wound management. Polysaccharides-based hydrogels with an interconnected three-dimensional network, and desired properties have great potential as a carrier for delivery of different herbal extracts for oral and topical applications. Herbal extracts are extensively used for wound healing purposes, individually or in combination with other active agents. This study summarizes the current knowledge acquired on the preparation, functionalizing, and application of different kinds of polysaccharide-based hydrogels enriched by herbal extracts for different wound healing applications. The structural, biological, and functional impact of the polysaccharides and herbal extracts on the final hydrogel characteristics, as well as their influence on the different phases of the wound healing process have been discussed., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Objectives: Routine therapies cannot control refractory stable angina, leading to a high economic burden and an impaired quality of life. Persian medicine incorporates exceptional attention to lifestyle and nutrition to prevent and treat various diseases. Previous studies have reported the analgesic and anti-inflammatory effects of wet cupping. The present study aims to determine the effects of nutrition and cupping on refractory stable angina patients., Methods: Forty male patients with refractory stable angina were randomly allocated to four groups, including nutrition modification based on Persian medicine, wet cupping, nutrition modification along with wet cupping, and control. The primary outcomes were the changes in pain score using a visual analog scale and quality of life using the Seattle angina questionnaire. The secondary outcomes were changes in the exercise test and blood pressure., Results: The results of the present study revealed that 30 days of treatment with nutrition modification based on Persian medicine, cupping, and modified nutrition and cupping along with standard treatment for stable angina significantly increased the patient's quality of life and exercise test results while reducing pain, and systolic and diastolic blood pressure., Conclusion: Applying complementary Persian medicine methods such as nutrition modification and cupping along with the classical medical treatments may improve outcomes for refractory stable angina patients., Competing Interests: CONFLICT OF INTEREST The authors declare that there are no conflicts of interests., (© 2022 Korean Pharmacopuncture Institute.)

Bachground and aim: Coronavirus disease 2019(COVID-19), which is the pandemic of 21st century, is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Prognostic factors play an essential role in predicting the patients who need more care. Therefore, the current study aimed to investigate the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) ratio as discriminated indexes in prognosis of patients with COVID-19., Methods: Age, NLR, PLR, white blood cell (WBC), neutrophil count, lymphocyte count and platelet from 1007 hospitalized patients with COVID-19, who were admitted to two referring hospitals  in Ardabil, North Western Iran. All confirmed cases divided into non-severe and severe groups., Results: 534 (53.4%) males and 473 (47.3 %) females with mean age of 52 years were enrolled in this study. Patients with severe COVID-19 have lower counts of lymphocyte, but have higher NLR, comparing to non-severe patients (P = 0.001)., Conclusion: Elevated NLR can be assumed as an independent biomarker, which could provide a crucial indicator in the monitoring patients with COVID-19 on admission. Increased NLR was correlated with the severity of COVID-19. Assessment of NLR could be proposed to identify high risk individuals with COVID-19.

Background: In low and middle-income countries (LMICs), where millions of women give birth before the age of 18, the reproductive health status of married adolescent mothers, including family planning, sexual, psychosocial, and maternal health, remains a significant and recurring phenomenon. As a result, the purpose of this study was to assess the reproductive health status of married adolescent mothers who sought treatment at Ardabil health care centers in 2019., Methods: A cross-sectional study was carried out in five health centers in Ardabil, Iran. This research included 312 married adolescent mothers who were under 19 years old. Health workers who asked questions of each participant completed a demographic questionnaire and the Reproductive Health Assessment Scale for Married Adolescent Women, and all data were self-reported. Univariate and multivariate linear regressions were used to determine risk factors associated with reproductive health scores. The data was examined using statistical software (SPSS version 20)., Results: The mean age (years) of the respondents was 16.41 ± 0.85, the mean age of their husbands was 24.18 ± 2.29, and the mean age of their marriage was 15.06 ± 1.15. In this study, adolescent mothers had an average reproductive health score of 63.78 ± 11.06. There was a significant association between reproductive health status and age, education, husband's age and education, and contraceptive methods among married adolescent mothers (p < 0.05)., Conclusion: The research findings indicated that adolescent mothers had an average level of reproductive health. Several socio-demographic characteristics, including age, education, gravida, and contraception, were linked to reproductive health scores. Programmers and policymakers should prioritize improving the reproductive health of adolescent mothers through education and increasing women's and spouses' knowledge and awareness., (© 2022. The Author(s).)

Because of the intrinsic complexity, the classification of wounds is important for the diagnosis, management, and choosing the correct treatment based on wound type. Generally, burn injuries are classified as a class of wounds in which injury is caused by heat, cold, electricity, chemicals, friction, or radiation. On the other hand, wound healing is a complex process, and understanding the biological trend of this process and differences in the healing process of different wounds could reduce the possible risk in many cases and greatly reduce the future damage to the injured tissue and other organs. The aim of this review is to provide a general perspective for the burn wound location among the other types of injuries and summarizing as well as highlighting the differences of these types of wounds with emphasizing on factors affecting thereof.

Background: Crimean-Congo hemorrhagic fever (CCHF) is an acute, feverous disease that is caused by tick bites or humans' direct contact with the blood and tissues of infected livestock and humans. The transmission of the disease is also possible via human-to-human contacts and nosocomial transmission is well described. The majority of patients suffering from this disease are slaughterhouse workers (including butchers), farmers, veterinarians and hospital staff. Thus, this study aimed to investigate the health behaviors of butchers regarding CCHF and study factors affecting such behaviors based on the health belief model., Methods: This is a descriptive cross-sectional study conducted on 500 butchers in Ardabil Province in 2020 by a multistage sampling method. The participants of the study completed the researcher-made questionnaire of health belief model and health behaviors model relevant to CCHF. The collected data were then analyzed by descriptive statistical tests and linear regression analysis., Results: The mean (SD) age of the participants was 44.4 (10.5) years, and 96% were males. Only 11.1% of the participants displayed acceptable disease-preventive behaviors. The validity and reliability of the developed questionnaire were confirmed. The results of the exploratory factor analysis showed that the constructs of the model explained 84% of the total variance. The results of the study revealed that among the variables of the health belief model, perceived susceptibility (p-value = 0.006, β = 0.152) and perceived barriers (p-value = 0.023, β = 0.14) were the strongest factors predicting disease-preventive behaviors regarding CCHF., Conclusion: The results of the study showed that the health belief model can predict preventive behaviors for CCHF. Therefore, designing and executing interventions based on the results of this study may encourage such preventive behaviors in butchers., (© 2022. The Author(s).)