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Abstract: This study investigates the ability of a 2-D CFD (computational fluid dynamic) simulation in estimating the hourly yield of a single-slope solar still. Moreover, a new equation based on Chilton–Colburn analogy is proposed to estimate the productivity of a solar still. The results are in a good agreement with the results of well known models. However, the accuracy of the CFD analysis in the prediction of Nu number is better than its accuracy in productivity estimation. The results also show that there is an optimum length in which the productivity is maximized. On the other hand, in a fixed length of a solar still, the specific height has an inverse effect on productivity. Moreover, the trend of water productivity is always similar to the trend of convective heat transfer coefficient. [Copyright &y& Elsevier]

Abstract: In this study, an attempt has been made to design a new type portable thermoelectric solar still (PTSS). In the PTSS, a thermoelectric module is used to improve the temperature difference between evaporating and condensing zones. Also, a heat-pipe cooling device is used to cool down the hot side of the thermoelectric cooler. To evaluate the performance of the PTSS, the equipment was tested under the climatic condition of Semnan (35° 33′ N, 53° 23′ E), Iran. The experiments were carried out in 5days. The measurement of solar intensity, wind velocity, ambient temperature, water production, and temperature of other components, for example, thermoelectric module, water, walls and heatpipe was done in the same manner for each day. The results showed that ambient temperature and solar radiation have a direct effect on still performance but there is a reduction in water productivity by increasing the wind speed. The results also showed that temperature of thermoelectric device was lower than that of walls which indicated on the higher production of water. [Copyright &y& Elsevier]

ABSTRACT This paper presents the results of a computational and experimental effort to develop crack-resistant dental multilayers that are inspired by the functionally graded dento-enamel-junction (DEJ) structure that occurs between dentin and enamel in natural teeth. The complex structures of natural teeth and ceramic crowns are idealized using flat-layered configurations. The potential effects of teeth-on-teeth contact are then modelled using finite element simulations of Hertzian contact. The resulting stress distributions are compared for a range of possible bioinspired, functionally graded architecture. The computed stress distributions show that the highest stress concentrations in the top ceramic layer of crown structures are reduced significantly by the use of bioinspired functionally graded architectures. The reduced stresses are experimentally shown to be associated with significant improvements (∼32%) in the pop-in loads. The implications of the results are discussed for the design of bioinspired dental ceramic crown structures. The bioinspired functionally graded layers are also shown to promote improvements in the critical crack size. [ABSTRACT FROM AUTHOR]

The thermal shock resistance of porous ceramic materials is often characterized by the Hasselman parameters. However, in other scenarios, the room-temperature residual strengths after thermal shock are also used to quantify the damage due to thermal shock. This paper attempts to link the measured residual strengths to the dominant crack features that are introduced due to thermal shock in porous clay ceramics produced by the sintering of clay powders with well-controlled size ranges. Residual strength estimates from bend tests are compared with fracture mechanics predictions. The implications of the residual strength results are then discussed for the characterization of damage due to thermal shock. [ABSTRACT FROM AUTHOR]

Abstract: A carbon paste electrode is modified with ZrO2-nanoparticles and its application for square wave voltammetric (SWV) detection of methyl parathion, MP (organophosphate pesticide) is reported. The nano-ZrO2 shows a strong affinity toward the phosphate group on methyl parathion molecules, which provides sensitivity and selectivity of the modified carbon paste electrode. Instrumental and chemical parameters influencing the voltammetric response are optimized for MP determination. Under optimum experimental conditions the peak current is linear to MP concentration over the range of 5.0–3000.0ngmL−1 with a correlation coefficient of 0.9992. The limit of detection (LOD) and limit of quantification (LOQ) for MP based on three and ten times the standard deviation of the blank (3S b, 10S b) were 2.0 and 5.7ngmL−1 (n =20) for MP, respectively. The recovery values from quality control (QC) samples of water solutions containing low, middle and high concentrations of MP (50, 100 and 800ngmL−1) were 98.0±2.3%, 92.5±4.9% and 97.6±2.8%, respectively. The electrode is successfully applied for the determination of MP in different water samples. [Copyright &y& Elsevier]

Abstract: Parylene can be coated on stainless steel substrates with and without γ-methacryloxypropyltrimethoxysilane (γ-MPS) as an adhesion promoter. In order to study the effects of silane (γ-MPS) on the adhesion and mixed-mode interfacial fracture performance between parylene C and 316L stainless steel, this paper presents the results of a combined experimental and theoretical approach. Atomic force microscopy (AFM) was used to obtain pull-off forces between parylene coated AFM tips with or without γ-MPS and 316L substrates. A combination of adhesion theories and fracture mechanics models was then used to obtain estimates of the fracture energy release rates over a wide range of mode mixities between pure mode I and pure mode II. The trends in the estimates were shown to be in good agreement with experimental measurements of interfacial fracture toughness obtained from Brazil nut tests coated with parylene C in the presence or absence of γ-MPS over the same range of mode mixities. The study determined that the contribution of silane to the adhesion of parylene C to 316L steel was modest. [Copyright &y& Elsevier]

A new method using a mini-column packed with sulfur as a new solid phase extractor has been developed for simultaneous preconcentration of lead and cadmium in water samples prior to flame atomic absorption spectrometric determinations. The effects of various parameters such as pH, flow rate of sample and eluent, type and concentration of eluent, sample volume, amount of adsorbent and interfering ions have been studied. The calibration graph was linear in the range of 10–300 and 1–20ngmL−1 for lead and cadmium, respectively. The limit of detection based on three times the standard deviation of the blank (3S b) was 3.2 and 0.2ngmL−1 (n =10) for lead and cadmium, respectively. A preconcentration factor of 250 was achieved in this method. The proposed procedure was applied to the determination of metal ions in tap, river and wastewater samples. [Copyright &y& Elsevier]

Abstract: Laser surface texturing can be used to produce well defined micro-grooves on biomedical materials such as Ti-6Al-4V. Such micro-grooves can be optimized to improve the integration with surrounding tissue. This paper examines the effects of Gaussian shaped beam profiles for nano-second laser processing on the laser micro-groove geometry, topography, and micro-structure of Ti-6Al-4V under atmospheric conditions. Laser and machining parameters such as pulse rate, scan speed, wavelength, groove width and pitch are shown to affect the resulting micro-groove geometries. In contrast to prior micro-groove studies using top-hat beam profiles with ultra-violet (UV) Excimer lasers or large area masking techniques, grooves produced with Nd:YVO4 exhibit improved roughness parameters and reduced heat-affected zones. Initial processing parameters are established for the fabrication of micro-groove geometries on flat geometries that are relevant to biomedical implants and devices. [Copyright &y& Elsevier]

Current solutions to global challenges place tension between global benefits and local impacts. The result is increasing opposition to implementation of beneficial climate policies. Prioritizing investment in projects with tangible local benefits that also contribute to global climate change can resolve this tension and make local communities' partners instead of antagonists to change; the approach advocated is a new take on "thinking globally, acting locally". This approach is a departure from the usual strategy of focusing resources on solutions perceived to have the largest potential global impact, without regards to local concerns. Reclamation of polluted mine sites by using fast growing bamboo to remove heavy metals provides a case study to show what is possible. Effective implementation of thinking globally while acting locally will require increased coordination between different types of researchers, new educational models, and greater stakeholder participation in problem identification and solution development., Competing Interests: The authors declare no competing financial interests., (© 2024 The Author(s).)

Due to the small capacity of the eye cavity and the rapid drainage of liquid into the nasolacrimal duct, patients must frequently administer the drops. Nanoparticles (NPs) and in situ gel systems have each proven their ability to achieve eye retention independently. In this study, timolol-loaded chitosan-carbomer NPs were prepared using the polyelectrolyte complexation method, and incorporated into a pH-responsive in situ gel system made of carbomer. The rheological behavior of NPs-laden in situ gel was examined at room and physiological conditions. Characteristics such as zeta potential, surface tension, refractive index, mucoadhesive properties, drug release, transcorneal permeability, and intra-ocular pressure (IOP) lowering activity were investigated on NPS and NPs-laden in situ gel formulations. The optimum gained NPs system had an encapsulation efficiency of about 69% with a particle size of 196 nm. The zeta potential of the NP and NPs-laden in situ gel were - 16 and + 11 mV respectively. NPs-laden in situ gel presented enhanced viscosity at physiological pH. All physicochemical properties were acceptable for both formulations. NPs and NPs-laden in situ gel systems proved to sustain drug release. They showed mucoadhesive properties which were greater for NPs-laden in situ gel. IOP reduction by NPs-laden in situ gel was significantly higher and more long-lasting than the timolol solution and NPs. In conclusion, the developed NPs-laden in situ gel is a promising carrier for ocular drug delivery due to the slow release of drug from nanoparticles, its mucoadhesive properties, and high viscosity acquisition in contact with precorneal film, which lead to improved therapeutic efficacy., (© 2024. Controlled Release Society.)

Development of AS1411aptamer-conjugated liposomes for targeted delivery of arsenic trioxide is the primary goal of this study. AS1411aptamer was used as ligand to target nucleolin, which is highly expressed on the surface of melanoma cancer cells. The targeted liposomes were constructed by the thin film method, and arsenic trioxide was loaded as cobalt (II) hydrogen arsenite (CHA) to increase the loading efficiency and stability of the liposomes. The liposomal structure was characterized by Fourier Transform Infrared Spectroscopy (FT-IR) and field emission scanning electron microscopy (FESEM). In addition, particle sizes and zeta potential of the CHA-loaded liposomes (CHAL) and aptamer-functionalized CHA-loaded liposomes (AP-CHAL) were determined. In vitro cytotoxicity of CHAL and AP-CHAL were evaluated using MTT assay in murine melanoma (B16) and mouse embryonic fibroblast (MEF) cell lines. The encapsulation efficiency of CHAL and AP-CHAL was reported as 60.2 ± 6.5% and 58.7 ± 4.2%, respectively. In vivo antitumor activity of CHAL and AP-CHAL in the B16 tumor-xenograft mouse model was dramatically observed. All mice of both groups survived until the end of treatment and showed body weight gain. The tumor protrusion completely disappeared in 50% of the mice in these groups. Furthermore, histopathology studies demonstrated that CHAL and AP-CHAL did not induce significant toxicity in healthy mice tissues. However, unlike the CHAL group, which showed an initial increase in tumor volume, a specific antitumor effect was observed in the AP-CHAL group from the beginning of treatment. The results showed that AP-CHAL can be used as an effective drug delivery system with high potential in the treatment of solid tumors.

Understanding and controlling the diffusion of ions and chemicals within the secondary plant cell walls are pivotal in various applications of biomasses. Recent studies have shown that inorganic ion diffusion through secondary cell walls is controlled by a moisture-induced glass transition in amorphous polysaccharides, including amorphous cellulose and hemicelluloses. Understanding the diffusion of ions in these structures has been the subject of numerous recent experiments; however, a deep understanding of the underlying mechanisms of interactions between ion atoms and water/hemicellulose molecules is still lacking. This study uses molecular dynamics simulations to elucidate the diffusion mechanisms of potassium and chloride ions in the cell walls under varying moisture content. The results reveal that a higher moisture content leads to the formation of solvent layers around the ions and reduces the charge interaction between the functional groups of wood polymers and ions. Hence, a higher moisture content results in an improved diffusion rate of ions within the domain. The simulation results also show that higher moisture content lowers the glass transition temperature, promoting diffusion of ions in the system. In contrast, increases in the ion concentration increase the glass transition temperature of the system and degrade the diffusion of ions in the system.

Introduction: Mefloquine is an antimalarial medicine used to prevent and treat malaria. This medicine has some side effects, including ototoxicity. This study, which was designed in two phases, aimed to investigate the side effects of mefloquine and evaluate the preventive effects of electrical stimulation on these side effects., Methods: In the first phase, two doses of mefloquine (50 and 200 μM) were injected into male rats, and after 7 days, they were evaluated by an auditory brainstem response (ABR) test. In the second phase, electrical stimulation was applied for 10 days, and then a toxic dose of mefloquine was injected. Similar to the first phase of the study, the animals were evaluated by an ABR test after 7 days., Results: In the first phase, the results showed that a high dose of mefloquine increased the ABR threshold and wave I latency; however, these changes were not observed in the second phase., Conclusion: Application of electrical stimulation could prevent the ototoxic effects of mefloquine. According to the findings of the present study, electrical stimulation can be used as a preconditioner to prevent the ototoxic effects of mefloquine., (© 2023 S. Karger AG, Basel.)

Reliable and precise quantification of 25-hydroxyvitamin D 3 in clinical samples is vital because vitamin D 3 deficiency lead to several disorders, such as mental illness, osteoporosis, and coronavirus disease. Herein, we report the fabrication of a novel electrochemical aptasensor using a nanocomposite, including reduced graphene oxide, pyrrole, and l-cysteine, for the sensitive detection of 25-hydroxyvitamin D 3 . Subsequently, the aptamer of 25-hydroxyvitamin D 3 was immobilized on the surface of the modified electrode. Differential pulse voltammetry signals were utilized for studying the binding and measurement of 25-hydroxyvitamin D 3 based on the oxidation peak. Under the optimum conditions, the designed electrochemical aptasensor exhibited a linear detection range of 0.001-150 nM, with a limit of detection of 0.006 nM. Furthermore, the proposed aptasensor selectively detected 25-hydroxyvitamin D 3 compared to other analogs. Moreover, this aptasensor was successfully applied for the detection of 25-hydroxyvitamin D 3 in human serum samples, which were quantified by the enzyme-linked immunosorbent assay method. The acceptable recoveries of 82.67%-111.07% demonstrated that this proposed electrochemical aptasensor can be a promising alternative for clinical methods of vitamin D determination., (© 2023 International Union of Biochemistry and Molecular Biology, Inc.)

Background: We aimed to evaluate the various clinicopathodemographical, epidemiological, and molecular contributors to cumulatively worldwide metastatic colorectal cancer (CRC) in CRC patients from a highly populated area in northeastern Iran to pinpoint metastasis risk., Methods: A retrospective clinical material-based cohort including a total of 6260 registered CRC patients, of whom 3829 underwent surgery, from regional university hospitals, during 2006-2016, were analyzed for the clinicopathodemographical aspects of age, sex, stage of CRC, history of smoking, type 2 diabetes (T2D), hypertension, body mass index (BMI), familial/occupational status, post-surgery survival period and mRNA/protein expression of mucin stabilizer (B3GALNT2), mucin I (MUC1), key cell cycle molecules (i.e., P53 and Ki67), and MMR-related genes. Factors were set to estimate the risk of metastatic CRC and mortality., Results: Predominant adenocarcinomatous CRCs were found in colon. Post-surgery survival period of metastatic CRC patients was remarkably longer in patients aged > 50 compared to those aged < 50 years, and worse in females than males. B3GALNT2 high , MUC high , P53 low , and Ki67 high mRNA/protein expression in the metastatic stage III CRC along with T2D and hypertension were associated with increased metastasis/mortality, with more worsening in males, older, BMI > 25, urban residing, and employed individuals, indicative of non-genetic attributable factors., Conclusion: B3GALNT2, MUC1, and "Ki67" can be used as promising biomarkers for prognosis and early diagnosis of increasingly/predominantly non-genetic/environmental originated metastatic CRCs., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

Objectives: The objective assessment tests overcome the variability of subjective methods. Cortical recordings with gap pre-pulse inhibition of the acoustic startle reflex stimulus have been used as objective tinnitus assessments in humans. This study aims to investigate this possible objective tinnitus test and compare gap-induced inhibition in different stimulus parameters and brain regions., Materials & Methods: Twenty People (18-50 years old) without hearing loss and tinnitus were included. The sound stimuli consisted of continuous background noise with a loud startle tone preceded by a silent gap (20 and 40 ms duration, 120 and 150 ms distance from the startle). The N1-P2 complex amplitude and topoplot maps were extracted in 27-channel cortical response recording after signal processing. Four brain regions of interest (ROI) of anterior-frontal, centro-frontal, right, and left temporal were investigated., Results: The results showed that the maximum inhibition occurred in a 40 ms gap duration and 150 ms distance in all 4 ROIs. In comparing ROIs, the centro-frontal and left temporal regions revealed the most inhibition (p<0.05). The decrease in the amplitude of the N1 and P2 in that region could also be traced in the 100 and 200 ms topoplots., Conclusion: Gap-induced inhibition was observed in all gap-embedded stimuli and all ROIs. However, the 40-150 mode and centro-frontal and left temporal regions had maximum inhibition in normal subjects. It provides a promising tool for objectively assessing tinnitus in humans with particular implications in children., Competing Interests: The authors have no relevant financial or non-financial interests to disclose., (© 2023 The Authors.)

This study aimed to evaluate the efficacy and safety of evening primrose oil (EPO) for cervical ripening before gynecologic procedures and compare it to misoprostol. In this study, 40 hysteroscopy and dilation and curettage candidates were enrolled. Patients were randomly assigned to receive either 2000 mg of vaginal EPO (n = 20) or 200 μg of vaginal misoprostol (n = 20) 2 hours before the expected procedure. The measured outcomes were the size of the Hegar dilator that passed through the cervix effortlessly, uterine cervicovaginal complications, and drug-related side effects. The two groups were not significantly different in age, number of gravity, parity, type of delivery, and menopausal status (P > .05). The mean ± SD size of the first dilator was 5.25 ± 1.55 in the misoprostol group and 7.30 ± 1.08 in the EPO group (P < .001). The pain complaint in the EPO group was significantly lower (P = .027), but the two groups were not significantly different in terms of other complications. No cases of uterine or cervical rupture were seen in either group. The present study showed that 2000 mg of vaginal EPO was significantly more effective for cervical ripening than 200 μg of vaginal misoprostol before gynecological surgery. Therefore, it is recommended to use EPO as an alternative to misoprostol., (© 2023, The American College of Clinical Pharmacology.)

Background: Rheumatoid arthritis (RA) is a common chronic inflammatory disorder that can be associated with some hearing impairments. Hence, we aimed to evaluate the prevalence rate of hearing loss (HL) in RA patients., Materials and Methods: This study included 130 participants from February 2019 to March 2020 including 100 RA patients (78 females and 22 males) as RA group and 30 healthy cases (16 females and 14 males) as control group. All patients underwent pure tone audiometry, speech audiometry, tympanometry, acoustic reflex, and tone decay test by single operator and device. The rate of HL and contributing factors were then determined., Results: The mean age of RA group was 53.95 ± 7.6 years, and the mean duration of disease was 12.74 years. Rheumatoid factor was positive in 54% of patients, and the frequency rates of diabetes, chronic kidney disease, hypertension, and dyslipidemia among RA patients were 14%, 1%, 26%, and 19%, respectively. These values among RA patients with HL were 18%, 1.7%, 34%, and 27.5%, respectively. HL in RA patients was related to dyslipidemia ( P = 0.011) and age ( P = 0.0001). Frequency rate of conductive HL in left and right ears was 2% and 5%, respectively, and these rates for sensorineural hearing loss (SNHL) were 55% and 61%, respectively. In addition, the percent of HL in low, mid, and high frequency ranges was 18%, 19%, and 57%, respectively., Conclusions: The findings of the present research demonstrate that HL especially with SNHL and high-frequency types is common among RA patients., Competing Interests: There are no conflicts of interest., (Copyright: © 2023 Advanced Biomedical Research.)

Biomaterials are an important source of inspiration for the development of strong and tough materials. Many improved and optimized synthetic materials have been recently developed utilizing this bioinspiration concept. Using side-chain-to-side-chain polymerization of cyclic β-peptide rings, a novel class of nanomaterials was recently introduced with outstanding mechanical properties such as toughness values greater than natural silks. In this work, molecular dynamics is used to understand the mechanics of side-chain-to-side-chain polymerization of cyclic β-peptide rings. Unbiased steered molecular dynamics simulations are used to show the difference in the strength of polymerized and unpolymerized processing of similar cyclic rings. The simulations are performed both in aqueous and vacuum environments to capture the role of water on the mechanical properties of the cyclic peptides. Our results show that unpolymerized peptides behave like brittle material, whereas polymerized ones can withstand some stress after initial failure with large values of strain-to-failure. Finally, we have shown that the strength of cyclic peptides in water is higher than in a vacuum.

Liposomes have been attracted considerable attention as phospholipid spherical vesicles, over the past 40 years. These lipid vesicles are valued in biomedical application due to their ability to carry both hydrophobic and hydrophilic agents, high biocompatibility and biodegradability. Various methods have been used for the synthesis of liposomes, so far and numerous modifications have been performed to introduce liposomes with different characteristics like surface charge, size, number of their layers, and length of circulation in biological fluids. This article provides an overview of the significant advances in synthesis of liposomes via active or passive drug loading methods, as well as describes some strategies developed to fabricate their targeted formulations to overcome limitations of the "first-generation" liposomes., Competing Interests: The authors declare that they have no competing interests., (©2023 The Authors.)