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The primary objective of the present study is to systematically investigate the solubility data and thermodynamic properties associated with codeine phosphate within mixtures comprising ethylene glycol (EG) and N-methyl-2-pyrrolidone (NMP) under atmospheric pressure conditions within the temperature range of 293.2–313.2 K. The analysis reveals a discernible positive correlation with both temperature and the ratio of EG. Mathematical models are employed for the purpose of correlating the obtained data, and the reliability of these models is rigorously assessed through the computation of mean relative deviations for back-calculated values. Additionally, the density values of codeine phosphate saturated mixtures are meticulously measured and subsequently correlated utilising the Jouyban-Acree model. Furthermore, the apparent thermodynamic properties governing the solubilisation process of codeine phosphate, including standard enthalpy, entropy and Gibbs free energy, are computed through the application of Gibbs and van’t Hoff equations, and the obtained results are comprehensively documented. [ABSTRACT FROM AUTHOR]

The information obtained from customers' feedback can help hotel managers improve their provided services in a targeted manner according to customers' expectations. Besides, other customers consider online hotel scores an efficient tool for quickly evaluating the quality of hotels' services. Therefore, a higher online score indicates customer satisfaction and would lead to more bookings, price acceptance, and higher financial performance. In this article, we extracted the shortcomings related to hotel attributes utilizing a novel methodology that comprises machine learning algorithms, text mining, and a combination of customers' comments and scores. Then we examined the quantitative effect of fixing these problems on hotels' online scores. Furthermore, considering the origin of the problems, the cost required for fixing them, and the quantitative effect of solving them on improving the hotels' online scores, we provided some prescriptions for hotel managers as the last phase of business analytics. This model and its resulting prescriptions can be used to increase hotels' online scores significantly by improving service quality at the lowest cost. Finally, to describe the most important attributes, we used The Nordic European School of thought and classified them based on the technical and functional dimensions of Grönroos' service quality model. [ABSTRACT FROM AUTHOR]

AbstractCancer is ranked among the top causes of mortality throughout the world. Conventional therapies are associated with toxicity and undesirable side effects, rendering them unsuitable for prolonged use. Additionally, there is a high occurrence of resistance to anticancer drugs and recurrence in certain circumstances. Hence, it is essential to discover potent anticancer drugs that exhibit specificity and minimal unwanted effects. Curcumin, a polyphenol derivative, is present in the turmeric plant (Curcuma longa L.) and has chemopreventive, anticancer, radio-, and chemo-sensitizing activities. Curcumin exerts its anti-tumor effects on cancer cells by modulating the disrupted cell cycle through p53-dependent, p53-independent, and cyclin-dependent mechanisms. This review provides a summary of the formulations of curcumin based on nanospheres, since there is increasing interest in its medicinal usage for treating malignancies and tumors. Nanospheres are composed of a dense polymeric matrix, and have a size ranging from 10 to 200 nm. Lactic acid polymers, glycolic acid polymers, or mixtures of them, together with poly (methyl methacrylate), are primarily used as matrices in nanospheres. Nanospheres are suitable for local, oral, and systemic delivery due to their minuscule particle size. The majority of nanospheres are created using polymers that are both biocompatible and biodegradable. Previous investigations have shown that the use of a nanosphere delivery method can enhance tumor targeting, therapeutic efficacy, and biocompatibility of different anticancer agents. Moreover, these nanospheres can be easily taken up by mammalian cells. This review discusses the many curcumin nanosphere formulations used in cancer treatment. [ABSTRACT FROM AUTHOR]

Earthquake-induced pounding in bridges is a complex contact phenomenon in which the dynamic responses of structures, including collisions between deck and abutments, are strongly related to structural properties and earthquake excitation. The goal of this study is to develop and compare the seismic fragility curves of overall system and individual components of regular and irregular box-girder highway bridges in two cases: with pounding and without pounding. For this purpose, four levels of altitudinal irregularity, ranging from regular to highly irregular, are considered. To extend the results for all bridges in the same class, different sources of uncertainties related to earthquakes, structural geometries, and material properties are taken into account. The analytical fragility curves have been developed based on nonlinear time history analyses in OpenSees finite element software for the cases with and without pounding effects. The process has been repeated for each two-, three-, and four-span classes at four irregularity levels. The fragility function parameters for the two cases with and without pounding have been compared for all classes considered in this study. Using fragility functions, this paper clarifies the interactive roles of irregularity and pounding between deck and abutments for seismic vulnerability of multi-span box-birder highway bridges. The results indicate that collisions often show an adverse effect on all structural components. It has also been observed that the detrimental effect of pounding on seismic fragility is more apparent in irregular bridges when compared with regular ones. In addition, the study introduces a conversion coefficient to clarify the effects of pounding on the fragility of bridge components and the overall system. This coefficient can be applied in both conventional analytical methods like static or simplified analysis and technical earthquake models like HAZUS, adjusting fragility values for pounding and irregularity effects. [ABSTRACT FROM AUTHOR]

The liver performs a wide range of biological functions that are essential to body homeostasis. Damage to liver tissue can result in reduced organ function, and if chronic in nature can lead to organ scarring and progressive disease. Currently, donor liver transplantation is the only longterm treatment for end-stage liver disease. However, orthotopic organ transplantation suffers from several drawbacks that include organ scarcity and lifelong immunosuppression. Therefore, new therapeutic strategies are required. One promising strategy is the engineering of implantable and vascularized liver tissue. This resource could also be used to build the next generation of liver tissue models to better understand human health, disease and aging in vitro. This article reviews recent progress in the field of liver tissue bioengineering, including microfluidic-based systems, bio-printed vascularized tissue, liver spheroids and organoid models, and the induction of angiogenesis in vivo. [ABSTRACT FROM AUTHOR]

Flow over an oscillating cylinder has been the subject of various studies as well as its heat transfer characteristics due to the lock-in phenomenon which occurs as a result of multiple frequencies being present in the system. The motivation was to investigate the effect of superhydrophobicity on heat transfer and wake dynamics of partially superhydrophobic oscillating cylinder. Applying the slip condition causes the drag and root-mean-square lift coefficients to reduce by 46 and 75% in comparison to the no-slip case, respectively. It also augments the average Nusselt number by 55% accompanied by a 21% increase of the natural shedding frequency compared to the no-slip cylinder. Considering the reduction of force coefficients, it is shown that the application of slip over a 135° segment of the surface is an optimum case, resulting in 47% and 85% decrease of the drag and root-mean-square lift coefficients, respectively. Application of slip over the surface of the cylinder also causes the average Nusselt number to become nearly 6 times greater than the no-slip oscillating cylinder at the lock-in condition. Further analysis based on thermal performance index (TPI) proves that a high value of TPI = 6 can be reached for the superhydrophobic cylinder. [ABSTRACT FROM AUTHOR]

In the current work, the solubility of amlodipine besylate (ADB) was studied in the ethylene glycol + ethanol at different temperatures (293.2-313.2 K). The experimental solubility data obtained herein were correlated with some well-known cosolvency models and the accuracy of these models was investigated with the mean relative deviations of the back calculated data. The apparent thermodynamic parameters (Gibbs energy, enthalpy and entropy) of ADB in the non-aqueous saturated mixtures were also calculated with the van't Hoff and Gibbs equations at Thm. [ABSTRACT FROM AUTHOR]

The purpose of the current study is the investigation of the solubility data and thermodynamic properties of codeine phosphate in mixtures of N-methyl-2-pyrrolidone and 1-propanol under atmospheric pressure at 293.2–313.2 K. Positive correlations of the solubility with temperature and N-methyl-2-pyrrolidone ratio were observed. The measured data were correlated using some mathematical models, and their reliability was studied by computing the mean relative deviations of the back-calculated values. The density values of codeine phosphate saturated solutions were also measured and correlated using the Jouyban–Acree model. Furthermore, the apparent thermodynamic properties of the codeine phosphate solubilisation (e.g. standard enthalpy, entropy, and Gibbs free energy) are also computed based on Gibbs and van't Hoff equations and reported. [ABSTRACT FROM AUTHOR]

The objective of this study was to identify the relationship between hospitalization treatment strategies leading to change in symptoms during 12-week follow-up among hospitalized patients during the COVID-19 outbreak. In this article, data from a prospective cohort study on COVID-19 patients admitted to Khorshid Hospital, Isfahan, Iran, from February 2020 to February 2021, were analyzed and reported. Patient characteristics, including socio-demographics, comorbidities, signs and symptoms, and treatments during hospitalization, were investigated. Also, to investigate the treatment effects adjusted by other confounding factors that lead to symptom change during follow-up, the binary classification trees, generalized linear mixed model, machine learning, and joint generalized estimating equation methods were applied. This research scrutinized the effects of various medications on COVID-19 patients in a prospective hospital-based cohort study, and found that heparin, methylprednisolone, ceftriaxone, and hydroxychloroquine were the most frequently prescribed medications. The results indicate that of patients under 65 years of age, 76% had a cough at the time of admission, while of patients with Cr levels of 1.1 or more, 80% had not lost weight at the time of admission. The results of fitted models showed that, during the follow-up, women are more likely to have shortness of breath (OR = 1.25; P-value: 0.039), fatigue (OR = 1.31; P-value: 0.013) and cough (OR = 1.29; P-value: 0.019) compared to men. Additionally, patients with symptoms of chest pain, fatigue and decreased appetite during admission are at a higher risk of experiencing fatigue during follow-up. Each day increase in the duration of ceftriaxone multiplies the odds of shortness of breath by 1.15 (P-value: 0.012). With each passing week, the odds of losing weight increase by 1.41 (P-value: 0.038), while the odds of shortness of breath and cough decrease by 0.84 (P-value: 0.005) and 0.56 (P-value: 0.000), respectively. In addition, each day increase in the duration of meropenem or methylprednisolone decreased the odds of weight loss at follow-up by 0.88 (P-value: 0.026) and 0.91 (P-value: 0.023), respectively (among those who took these medications). Identified prognostic factors can help clinicians and policymakers adapt management strategies for patients in any pandemic like COVID-19, which ultimately leads to better hospital decision-making and improved patient quality of life outcomes. [ABSTRACT FROM AUTHOR]

In this research, polyoxyethylene with alkyne end groups and two disulfide bonds in the polymer chain was synthesized through two consecutive esterification reactions from polyethylene glycol (PEG). A new PEG-based hydrogel with exceptional structural features was prepared from the polycycloaddition reaction of this macro-dialkyne with a triazidohydrin obtained from trimethylolpropane triglycidyl ether. The network structure of the hydrogel was investigated by FT-IR spectroscopy, elemental analysis, field emission-scanning electron microscopy (FE-SEM) and energy dispersive X-ray (EDX) spectroscopy. The swelling behavior of the prepared hydrogel in water was studied by drawing the graph of water uptake percentage versus time. It was found that the hydrogel has the ability to absorb water more than five times its dry weight within 12 h. The water uptake rate of the prepared hydrogel was compared with several other hydrogels with similar structure. In addition to water, the swelling behavior was also checked in a number of organic solvents with different dipole moments. The prepared hydrogel showed significant solvent uptake (slightly more than twice the dry weight) in methanol and N,N-dimethylformamide solvents. [ABSTRACT FROM AUTHOR]

Thermoplastic elastomer polyurethanes (TEPUs) were synthesized for orthodontic ligature application and the relationship between various properties and structure of the synthesized TEPUs were studied. Polyethylene glycol and 1,4-butanediol were utilized in various weight ratios as chain extender. Fourier-transform infrared spectroscopy, differential scanning calorimetry, and X-ray diffraction were used to study the chemical and physical properties and also, tensile, stress relaxation, and elasticity analysis were performed to evaluate the mechanical properties of the prepared samples. Shape memory and stress relaxation analysis with temperature variation showed that the samples could recover the relaxed force due to the shape memory capability. [ABSTRACT FROM AUTHOR]

Alcalase enzyme (1 mg) and ultrasound (400 W) at 0–20 min were applied to obtain sulfated polysaccharides from yellowfin skin. Applying 15 min ultrasound resulted in a 0.12% increase in the rate of recovery yield. The intact structure of polysaccharides was determined by Fourier transform infrared spectroscopy, X-ray diffractometry, and scanning electron microscope. Ultrasound improved the thermal behavior of sulfated polysaccharides by affecting their microstructure, as analyzed by DSC. The color characterization (L*, a*, and b*) of ultrasound-treated samples was found to be superior compared to the control. Applying 15 min led to 16% and 9% enhancing DPPH and ABTS radical scavenging activities along with improving ferric-reducing antioxidant power of the polysaccharide. [ABSTRACT FROM AUTHOR]

The highest yield (34%) and imino acid (18.7%) of collagen were obtained from yellowfin tuna (Thunnus albacares) skin using 20 min ultrasound. The collagen was identified as type I collagen according to the results of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and its structure remained intact, proved by ultraviolet spectroscopy (UV) and fourier transform infrared spectroscopy (FTIR). Collagen solubility was superior in acidic and low salt environments. Ultrasound cavitation for 20 min improved collagens' emulsifying (EAI: 78.8 m2/g and ESI: 110.3 min) and foam properties (FA: 151.8% and FS: 133.3%) and water holding capacity (51.9%) by enhancing internal hydrophobic interactions and surface hydrophobicity. 20 min ultrasound resulted in desirable DPPH (61.1%) and ABTS (53.1%) radical scavenging and ferric-reducing antioxidant power (0.078 ABS). [ABSTRACT FROM AUTHOR]

Mathematical modelling is an interlinking process between mathematics and real-world problems that can be applied as a means to increase motivation, develop cognitive competencies, and enhance the ability to transfer mathematical knowledge to other areas of science, such as engineering disciplines. This study was designed to investigate the effect of applying the modelling approach on problem-solving and mathematical performance of engineering undergraduates during a differential equations (DEs) course and compare the results with those of conventional teaching. A quasi-experimental method comprising a pretest-posttest design with a control group was applied in this study. Since the antecedent knowledge of calculus directly influences the ability of students to learn DEs, a placement test was first applied to both groups. A combination of results derived from the placement test and the modelling pretest was used as the covariate in the Analysis of Covariance (ANCOVA), and the modelling and mathematical performances of both groups were eventually examined. The results of this study indicate that apart from the fact that teaching DEs based on the modelling approach can increase the ability to apply mathematical knowledge in the field of engineering, it also can significantly enhance their problem-solving and mathematical performances. [ABSTRACT FROM AUTHOR]

Our aim in the present study was to explore the cultural and social factors for child marriage in Sanandaj, Iran. In this qualitative study, semi-structured individual interviews were employed to collect data from the women married under the age of 18, their parents, and key informants. Thematic analysis was used to generate new insights and concepts from the data, collected from 40 participants. The socio-cultural factors perpetuating child marriage, reported by participants, were; "neutralization of girls," "child marriage-inducing customs and beliefs," "determinant power of males," "technology and facilitators of child marriage." Families' efforts to marry their children, the acceptance of child marriage by law and norms, encouragement of social networks, neighborhoods, relatives, and peers all have a mutual and reinforcing interdependence, which facilitates child marriage in the community. So, the interaction of all these features should be taken into account while delving into child marriage phenomenon. Socio-cultural elements should be emphasized in all interventional efforts and micro- and macro-level health promotion policy-makings aiming at reducing the rate of child marriage. [ABSTRACT FROM AUTHOR]

Since the (Covid-19) pandemic outbreak, questioning regarding climate and incident of Covid-19 infection rates has been debated, while there is no clear research evidence until now in Iran. This study has focused on investigating the association between Covid-19 cases and demographic –meteorological factors in arid and semi-arid zones of Iran (from March 1, 2020, to January 31, 2022) by analyzing with Via Poisson and negative binomial regression. As a result, the incidence rate of both Covid-19 hospitalization and mortality cases reached peaks in the summer followed by the autumn. Interestingly, Covid-19 hospitalization cases are associated with humidity, temperature, and wind factors seasonally and monthly, but mortality cases are just associated with wind. In conclusion, the result demonstrated that demographicand meteorological factorsare positively and negatively associated with Covid-19 cases. Therefore, identifying the environmental factors contributing to the excess Covid-19 can help to prevent future pandemic waves in Iranian arid and semi-arid zone. [ABSTRACT FROM AUTHOR]

This research was performed to assess the concentration and health risk of eight trace elements (manganese (Mn), mercury (Hg), copper (Cu), lead (Pb), iron (Fe), zinc (Zn), cadmium (Cd), and arsenic (As)) in animal product samples (n = 120) in Markazi province of Iran by inductively coupled plasma optical emission spectrometry (ICP-OES). Some trace elements such as Mn, Hg, Cu, Pb, Fe, and Zn were detected in samples while Cd and As non-detected. Fe had the highest mean level of trace elements in meat samples (1551.28 ± 83.25 μg/kg). The levels of Pb and Hg in some samples were upper than the limit of the European Commission (EC) and the Institute of Standards and Industrial Research of Iran (ISIRI), International/National Standards for Heavy Metals, and U.S. Food and Drug Administration (FDA). Deterministic and probabilistic health risk assessment approaches to evaluate of the target hazard quotients (THQ) and carcinogenic risks (CR) index were applied. The Monte Carlo probability distributions revealed that the rank order of total target hazard quotient (TTHQ) was milk > meat > egg. The non-carcinogenic and carcinogenic index of toxic elements indicated that exposed population in Markazi province was safe (1> THQ, 10−4> CR), except Hg exposure for children in milk. [ABSTRACT FROM AUTHOR]

In this study, removal of P-Nitrophenol (PNP) as a nitro-aromatic contaminant from the aqueous medium have been investigated using the photochemical oxidation process by UV-activated periodate. The experiments were performed in a photochemical reactor with a volume of one litre. The central composite design (CCD) as a response surface method was applied for the experimental design and optimisation of the process parameters by design expert software. The aim of this study was to distinguish the optimum level of independent variables intended for the dependent variable. The selected independent variables were the initial concentration of PNP, initial pH, and the amount of initial concentration of KIO4 that could affect the degradation efficiency (DE) as response (dependent variable). The CCD demonstrated an excellent relationship between the independent and dependent variables. The mathematical equations and response surface plots were utilised to determine the interactions and explain the results. The optimum conditions were found to be at pH = 5.8, [KIO4] = 83.3 ppm, [PNP] = 10 ppm, and after 30 min of the process, 88% degradation efficiency was obtained. To verify the adequacy and prediction power of the model, the predicted optimum conditions were validated by the actual experiments. Furthermore, p-nitrophenol mineralisation was also examined under optimal conditions and displayed the ability of the process to mineralise 35% of p-nitrophenol after 30 min. Also electrical energy consumption of the process was obtained about 102.74 kWh/m3. [ABSTRACT FROM AUTHOR]

A metal-organic framework MIL-101(HPW) was synthesized by hydrothermal reaction, and phosphomolybdic acid (HPMo) was synthesized by its precursor solution. Then (Pd + Pt)/HPMo/MIL-101(HPW) with different wt% were prepared by the impregnation method. The synthesized samples were characterized by XRD, FT-IR, NH3-TPD, N2 adsorption, FESEM, and TGA, and their performances were investigated in n-hexane isomerization. Under the optimized operating conditions (temperature of 180 °C, H2/nC6 molar ratio of 2, and WHSV of 3 h−1), the appropriate yield for the nC6 isomerization was provided. The (0.2%Pd + 0.3%Pt)/50%HPMo/MIL-101(HPW) sample showed a lifetime of 720 min with 92.5% iC6 selectivity and 75.3% nC6 conversion. Kinetic modeling of the n-hexane isomerization reaction was also performed, in which the classical bifunctional mechanism was used to calculate the kinetic parameters. The validity of the bifunctional behavior was proved by the high value of the statistical correlation coefficient of this model. The apparent activation energy of this mechanism was calculated at 42.5 kJ mol−1. [ABSTRACT FROM AUTHOR]

Juvenile systemic lupus erythematosus (JSLE) is a multifaceted multifactorial disorder with an unclear etiopathogenesis. Environmental factors, genetic factors, and dysregulated and defective immune system responses are known to have a role in JSLE etiopathogenesis. NLRP3 inflammasome, as an important contributor to immune-mediated inflammatory responses, is assumed to be involved in JSLE etiopathogenesis. To determine whether the NLRP3 genetic variants are altered in patients with JSLE. Fifty-three patients diagnosed with JSLE and 56 healthy sex-matched controls were studied. NLRP3 (C/G rs10754558, C/T rs3806265, C/T rs4612666, A/C rs35829419) gene polymorphisms were evaluated using a TaqMan single-nucleotide polymorphism assay. C allele at position rs3806265 was detected in higher frequencies in patients than in the control group (37.74% vs 23.21%, P-value =.028). At the genotype level at the same position, CT has a significantly higher frequency in patients than the healthy subjects (75.47% vs 46.43%, P-value =.003). The NLRP3 rs3806265 CT genotype was detected at a higher frequency in patients with JSLE than in the healthy control group. [ABSTRACT FROM AUTHOR]

Abstract This research was conducted to design an interpretive structural model of factors affecting the prevention and control of violence and aggression in football fans. The statistical population of this study was entirely composed of sport experts, executive managers, sociologists, and management professors in Iran. Thirteen individuals were accordingly selected as the research sample using non-probability purposeful sampling. The effective factors were identified through library study and reviewing the theoretical foundations and research background. Confirming the content validity of these factors by considering experts’ opinions, 14 factors were finally identified. The interrelationships between the factors were determined using Interpretive Structural Modeling (ISM), and network analysis based on Decision Making and Trial Evaluation Laboratory (DEMATEL) was also employed to measure their importance, ranking them accordingly. The factors were categorized into four levels according to ISM. The highest level (first level) includes “match day service quality,” “fair refereeing,” “consolidation of social ties,” and “cognitive reconstruction of fans.” The second level contains “design, protection, and security of stadiums,” “patterning and identification,” and “use of calming techniques.” “Awareness and informing” and “anger control training” belong to the third level, while the lowest level (fourth level) includes “media,” “fan organizations,” “laws, regulations, and security solutions,” “moral education or persuasion,” and “teaching communication skills to fans.” Among them, the last level is fundamental, influencing the other factors. The results obtained in this work can be used as a basis for policymaking to reduce violence and aggression among football fans. [ABSTRACT FROM AUTHOR]

Abstract The crashworthiness behavior of horsetail-inspired sandwich tubes was analyzed in this study. Multilayer perceptron (MLP) algorithms with the Levenberg-Marquardt training algorithm (LMA) were used to predict force-displacement curve and optimize the geometrical parameters according to minimum peak crushing force and specific energy absorption. Based on the non-dominated sorting genetic algorithm II (NSGA-II) optimization results, the specimen with four core tubes and a thickness of 1 mm, and a height of 92 mm has the optimal crashworthiness performance. Finally, the optimal specimen is fabricated and the results of the numerical and MLP methods are validated versus experimental approach. [ABSTRACT FROM AUTHOR]

In the thick of austerity, small arts communities are tested to the brink. The Arts in the North of England had been hit with staggered funding cuts, almost halving resources available from arts funders, arts organisations and the councils. In 2013, the largest DIY space in Newcastle was forced to move, closing for 2 years whilst Morden Tower, a building rich in artistic heritage, fell in to such disrepair it was forced to close. A hole was left. The Old Police House, a small DIY rehearsal space for a DJ project in Gateshead, was just that. An old police house without heating or funding that, in response to community needs, became a make-shift venue and home to several young artists and projects. Seven years on with two venue moves, two changes of Prime Minister, the threat of a super-council looming over 'Newcastle-Gateshead' and competing programmers, what impact does DIY art have? How has the local artistic community changed? Do equity and equality still exist in a climate of prescriptive narratives from Arts Funders, tick-box feedback forms and tokenistic funding? This paper proposes to explore the challenges of running an urban experimental community arts venue within this cultural context, drawing on the authors' personal experiences as an active participant. [ABSTRACT FROM AUTHOR]

A series of 3-D scaffolds based on polylactic acid (PLA) and thermoplastic polyurethane (TPU) as major phase and hydroxyapatite nanoparticles (n-HA) were prepared by using the dual leaching technique. Fourier-transform infrared spectroscopy analysis showed that almost the interactions between the constituent materials can be identified based on their functional groups. The results of thermogravimetric analysis were used to obtain the best time to prepare the samples without residual of any progen additives. The scanning electron macroscopy images clearly proved that the dual leaching technique is an effective method to prepare the appropriate morphology and also a very good dispersion and distribution for n-HA can be obtained. Dynamic contact angles showed that the presence of TPU in the PLA matrix has a positive effect on the hydrophilicity of the scaffolds. The bulk modulus (κ) values of S-PLA70TPU30H5 in dry and wet conditions were 321 and 212 Pa, respectively and the compressibility coefficient (β) of pure samples was higher than that of other scaffolds, while among the nanocomposite samples, the compressibility coefficient of S-PLA70TPU30H5 and S-PLA50TPU50H5 samples in dry and wet conditions was higher than that of other samples. Biological tests such as 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) tetrazolium reduction assay, cell adhesion, 4′,6-diamidino-2-phenylindole (DAPI) analysis and alizarin red were also performed, and the results obtained for 3D scaffolds were good. In the DAPI analysis test, sample 3D-S-PLA70TPU30H5 showed good behavior, and also in the alizarin red test, the amount of minerals created in 3D-S-PLA50TPU50H5 was significant. Dual leaching technique was used to prepare cylindrical scaffolds with high porosity. 3D cylindrical scaffolds based on PLA/TPU/n-HA were proposed for use in cancellous bone. Bulk modulus and compressibility coefficient of 3D cylindrical scaffolds were obtained in wet and dry conditions. DAPI analysis showed the role of n-HA nanoparticles on cell growth in 3D cylindrical scaffolds. Alizarin red studies showed that sample PLA50TPU50H5 has more calcium content. [ABSTRACT FROM AUTHOR]

In this research, a new amphiphilic copolymer with an H-shaped macromolecular structure consisting of three hydrophobic blocks and two hydrophilic blocks were synthesized by a combination of ring-opening polymerization and click chemistry. The central chain and two of the side arms of the H-shaped structure were made of oxybutylene and hexanoate repeating units, respectively (hydrophobic segments). The remaining two side arms are made of oxyethylene repeating units (hydrophilic segments) that are connected to the rest of the structure through disulfide bonds. The prepared H-shaped macromolecules were characterized by elemental analysis (CHNS), FT-IR, and 1H-NMR techniques. Based on transmission electron microscopy (TEM) images, the amphiphilic nature of the H-shaped polymer allowed it to form spherical molecular assemblies with a mean diameter of about 80 nm. The critical micelle concentration (CMC) in an aqueous solution was determined using the fluorometric method (CMC = 4.76 × 10−3 mg/mL). According to the profiles obtained from dynamic light scattering (DLS), the resulting spherical micelles had a mean hydrodynamic diameter ( D ¯ H) of ∼95 nm with a low polydispersity index (PDI = 0.26). [ABSTRACT FROM AUTHOR]

In this paper, a microwave sensor with a meandered microstrip structure is introduced to measure the permittivity of the various liquids. The performance of the sensor is based on the change of operating resonance frequency during the absence and presence of materials in the sensing area. In this study, liquids including ethanol, methanol, aqueous glucose solution, and deionized water have been selected as samples under test. The proposed sensor has been implemented on RO4003 substrate with dimensions of 35 × 20 × 0.508 mm3 and operating frequency of 6.21 GHz in a free load state with a Q-factor of 506. When the samples are present in the sensing area, the frequency of the sensor shifts from 5.42 to 3.27 GHz. The sensitivity of 0.64% is obtained for the presented sensor. Compact size, linearity of changes, and low cost are the most important advantages of the sensor. The introduced sensor can be used in various fields of industrial, medical, and diagnostic due to its performance. [ABSTRACT FROM AUTHOR]

Objective: Collaborative information behavior researches explain different types of functions and activities that people utilize in teamwork information-oriented environments by interacting with each other. The aim of this paper is to analyze the methodological structure and identify the main variables in existing CIB, CIS, and CIR studies. Methodology: All papers extracted from international databases including Scopus and Web of Science from 1997 to 2019 were reviewed in terms of quality and appropriateness. Then the full text of 91 selected articles was assessed. Based on a prepared checklist, information was extracted in a variety of fields such as first author, year, main subject, type of study, analysis tools, variables studied, and number and type of participants. Finding: The evaluation of the articles' methodology showed that the most methodological structure was qualitative in 39 papers. Also, an investigation of the measurement tools showed that data were collected in 28 articles by questionnaire, 13 articles by interview, and questionnaire. Seventy-four percent of the selected studies have been done by mixed methods in the last five years. Conclusion: This systematic review investigated the published papers in the field of CIB, CIS & CIR to evaluating of the research content structures and components. Team awareness, interaction, information sharing, collaboration, division of labor, communication, problem-solving, and cognitive dimension have been identified as the main elements of CIB. [ABSTRACT FROM AUTHOR]

The epidemic of COVID-19 has been the most mathematically informative pandemic. The unprecedented information gives rise to some unprecedented models, problems, and discussions. One of these new matters is modeling the epicenters of a pandemic. The present paper is the first attempt to model the waiting time to introduce a new epicenter during a pandemic. This modeling is conducted in terms of time-to-event, the number of epicenters, and the normalized time. We model the waiting time data by an exponential distribution, therefore, the number of epicenters can be represented through a Poisson process. Then, the parameters are estimated by the method of moments and maximum likelihood method. All the simulations are the result of 10,000 runs conducted on MATLAB R2015b. It is expected to encounter 12 and 14 (with probability 95%, 3-24 and 7-23) epicenters from 15th May to 13th June and from June 14 to July 12, 2020, respectively. We forecast that the cumulative number of confirmed cases for coming epicenters is over 10,000 when they join the existing epicenters. The paper suggests that the time to epicenter is a suitable criterion to compare the spreading speed of an epidemic in different periods or even different epidemics. The study aims to model the time to the next epicenters during the pandemic COVID-19. The study introduces the time to epicenter as a criterion to study of spreading speed of an epidemic in different periods or compare different epidemics. The study deals with the number of cumulative confirmed cases at the time that a region become epicenter. The study proposes the Poisson process as the model to describe the number of epicenters. The study suggests that exponential distribution can model the time to event for the epicenters of COVID-19. [ABSTRACT FROM AUTHOR]

A series of 1,4-dihydropyridine (DHP) derivatives have been synthesized and evaluated against both promastigote and amastigotes forms. All compounds showed higher activity than the reference drug amphotericin B. However, they exhibited less activity than the reference drug glucantime, except compound 4e. These compounds showed excellent anti-promastigote and amastigote activities in range of low nanomolar and low micromolar, respectively. Among the screened compounds, 4d was found as the most potent compounds against promastigote form with EC50 value of 0.0001 nM and compound 4e was the most potent compound against amastigote form with EC50 value of 2.38 µM. Based on CC50 results, synthesized compounds were found nontoxic to macrophages. The study demonstrated that, the position and nature of the substituents on phenyl ring of C4 in the DHP ring and the length of the chain belonging to the ester groups influences the biological activity of these compounds. Based on docking studies, it was proposed that compounds 4d and 4e form key interactions with regions of PTR1 enzyme. [ABSTRACT FROM AUTHOR]

This study compares the effect of ZPD feedback with explicit feedback on accuracy in second language (L2) writing. It also examines the effect of focused vs. unfocused ZPD feedback on L2 writing development during teacher-student tutorial sessions. Four participants wrote five persuasive essays and were provided with ZPD or explicit feedback either in focused or unfocused form during five tutorial sessions. Following sociocultural theory (SCT) principles, the ZPD feedback provided was graduated, contingent, and dialogical. The results revealed that the learners who received ZPD feedback performed better than those who received explicit feedback in terms of accuracy. The results also showed that the use of focused and unfocused ZPD feedback yields different results both in terms of accuracy across sessions and shifts in the quality of feedback learners need within and across sessions. The findings lend support to the supremacy of SCT-inspired ZPD feedback in general and focused ZPD feedback in particular but raise important questions regarding the nature of teacher-student interaction during tutorial sessions, and the number and function of linguistic targets. The findings are discussed in the light of SCT and cognitive-interactionist views of corrective feedback, and their implications for theory, practice, and research are discussed in detail. [ABSTRACT FROM AUTHOR]

In this work, a novel nanoadsorbent is reported for the surface grafting of poly[(N, N- dimethylacrylamide)-co-(allyl acetoacetate)] onto zinc oxide nanoparticles by free radical polymerization method for removal of Pb(II) in water and biological samples. The obtained nanoadsorbent was characterized by thermogravimetric analysis, Fourier transform infrared spectroscopy, and scanning electron microscopy. The calibration curve was linear in the concentration range of 2–100 mg L−1 with a removal efficiency in the range of 70–98%. Under the optimal conditions, the nanoadsorbent offered high adsorption capacity (56.20 mg g−1), low limit of detection (S/N = 3) of 11 ng mL−1 and the limit of quantification (S/N = 10) of 37 ng mL−1 with a relative standard deviation of <2% (n = 3). The results indicate that the Freundlich isotherm model and pseudo-second-order kinetic model are the best models that describe the sorption system. [ABSTRACT FROM AUTHOR]

Aim: Low frequency stimulation (LFS) inhibits neuronal hyperexcitability following epileptic activity. However, knowledge about LFS' inhibitory mechanisms is lacking. Here, α1 and α2 adrenergic receptors' roles in mediating LFS inhibitory action on high-K+ induced epileptiform activity (EA) was examined in rat hippocampal slices. Materials and methods: LFS (1 Hz, 900 pulses) was applied to the Schaffer collaterals. Whole-cell, patch clamp recording was used to measure changes in CA1 pyramidal neurons' excitability. By applying high-K+ on hippocampal slices, EA was induced, and neuronal excitability increased. Results: When administered at the beginning of EA, LFS reduced neuronal excitability. In the presence of prazosin (10 µM, an α1 adrenergic receptor antagonist) and yohimbine (5 µM, an α2 adrenergic receptor antagonist), LFS' typically has a restorative impact on EA-induced membrane potential hyperpolarization and spike firing frequency, but this effect was reduced after high-K+ washout; These antagonists did not have a significant effect on LFS' inhibitory action on spike firing during EA. Conclusion: These findings suggest that LFS' anticonvulsant effect, on neuronal hyperexcitability following high-K+ EA, may be mediated partly through α adrenergic receptors in hippocampal slices. [ABSTRACT FROM AUTHOR]

This paper deals with residual lifetimes of sequential k-out-of-n systems when component lifetimes are dependent. Given the first j component failure times, an unbiased predictor for the (j + i)-th component failure time is derived. Maximum likelihood prediction of future component failure times is also studied. Estimation of the nuisance parameters is investigated under the conditional proportional hazard rates model with the Exponential baseline distribution and the Gumbel-Hougaard copula. Illustrative examples are also given. [ABSTRACT FROM AUTHOR]

Standard discontinuous Galerkin methods, based on piecewise polynomials of degree q = 0 , 1 , are considered for temporal semi-discretization for second-order hyperbolic equations. The main goal of this paper is to present a simple and straightforward a priori error analysis of optimal order with minimal regularity requirement on the solution. Uniform norm in time error estimates are also proved. To this end, energy identities and stability estimates of the discrete problem are proved for a slightly more general problem. These are used to prove optimal order a priori error estimates with minimal regularity requirement on the solution. The combination with the classic continuous Galerkin finite element discretization in space variable is used to formulate a full-discrete scheme. The a priori error analysis is presented. Numerical experiments are performed to verify the theoretical results. [ABSTRACT FROM AUTHOR]

Study of stiffness characteristics plays a key role in application of parallel robots in precision manufacturing. In this study, stiffness index improvement is utilised as the objective function to obtain optimal configurations and dimensions for parallel robots. The optimisation goal is to maximise the stiffness index throughout workspace of the robots. First, stiffness of the robots is obtained by the strain energy of main components of the robots and Castigliano’s theorem. For a more realistic simulation, compliance of moving platform of the robots is considered. Then a non-dominated sorting genetic algorithm (NSGA-II) is utilised to solve the optimisation problem. A comprehensive case study of stiffness analysis of three conventional SPS (spherical– prismatic–spherical) Stewart platforms to examine such a platform’s optimised design is performed. The relationship between the objective and decision spaces is investigated. A similar approach can be utilised to study optimised design for other parallel robots. Findings of this study provide a general stepwise and conceptual approach to the stiffness analysis of parallel robots that depends on design parameters and configuration of the robots. In case of Stewart platforms, 3SPS configuration was found to be optimised in terms of stiffness performance in their workspace. [ABSTRACT FROM AUTHOR]

Today adamantane, the simplest diamondoid, has attracted much attention, due to its unique structure and properties for the construction of nanostructured entities. 1,1′-biadamantane is a nearly rigid hydrocarbon formed from the covalent attachment of the two adamantane units. In this study, adamantane was first converted to 1,1′-biadamantane, and the obtained 1,1′-biadamantane was brominated to give its hexabromo derivative. The six bromine atoms in the hexabromo derivative were then substituted by six phenols via a Friedel-Crafts alkylation reaction to yield the novel hexakis (4-hydroxyphenyl) derivative. Also, hydrolysis of the heaxabromo derivative afforded the novel hexahydroxy derivative. [ABSTRACT FROM AUTHOR]

One-pot three-component reactions of tetra aromatic aldehyde, including ether groups, derivatives of barbituric acid with ammonia, and ammonium acetate, result in new poly barbituric moiety and, correspondingly, tetra pyrimidodipyrimidine heterocycles. IR, 1H-NMR, and 13C-NMR spectroscopy along with CHN analyses were used to derive the structures of the products. Moreover, the synthesized compounds were investigated in terms of biological performance, consisting of toxicity examination, along with antioxidant, anti-inflammatory, and antibacterial activities. [ABSTRACT FROM AUTHOR]

The present article studies free vibration analysis of sandwich doubly curved shell composed of a honeycomb core and carbon nanotubes (CNTs) reinforced piezoelectric face-sheets. First-order shear deformation theory as well as Hamilton's principle is employed to derive the governing equations of motion. The effective material properties of core and face-sheets are estimated using the Gibson's formula and extended rule of mixture, respectively. The governing equations of motion are solved for simply supported boundary conditions to investigate the variation of natural frequencies of sandwich doubly curved shell in terms of important parameters of core and face-sheets such as side length ratio and length to thickness ratio of honeycomb cell, volume fraction, and distribution of CNTs and overall geometric parameters of the sandwich doubly curved shell. It is concluded that the maximum and minimum values of natural frequencies are obtained for FG-VA and FG-AV, respectively. [ABSTRACT FROM AUTHOR]

Soil organic carbon (SOC), is one of the most important parameters determining soil quality and fertility, crop productivity as well as soil resistance to drought. Therefore, the preparation of accurate maps of SOC is of great importance not only for precision agriculture but also for selection of suitable strategies by policy makers. Iran suffers from deficiency of a comprehensive dataset of SOC in agricultural lands. Therefore, this study aimed to present the SOC map of Iran´s agricultural soils, to compare SOC content of different agricultural land use and to compare SOC of agricultural lands in different Iran´s agro-ecological zones (AEZs). For this purpose, 3327 sites were sampled. These sampling sites were located in different Iran´s agricultural land use types (irrigated agricultural lands (AgI), dry farming (AgD), horticultural (Ho) and fallow (Fa) lands) of Iran´s AEZs, which were selected based on soil and geology maps as well as using a 6000 × 6000 m grid-sampling pattern. According to SOC map of Iran, only 4% of all agricultural lands of Iran (0–30 cm) possessed >2% SOC. This area is located in AEZ2 with wet and humid conditions and expanse covers the western coast of the Caspian Sea. The SOC content in 70% of Iran´s agricultural topsoil is less than 1%. Meanwhile, about 10% of the topsoil ´agriculturallands had SOC more than 1.5%. In addition, among different studied land uses, SOC content of surface soil decreases as this trend Ho>AgI> AgD> Fa because of more SOC accumulation in horticultural and irrigated agricultural lands than dry farming and fallow ones. In addition, more dairy manure applied in the horticultural lands. According to the results of SOC map, it is essential to manage agricultural strategies for better SOC sequestration in different AEZs in order to achieve sustainable agriculture. [ABSTRACT FROM AUTHOR]

Abstract We consider the effect of adding three different types of standby components to a k–out–of–n:F system based on the dynamic stress–strength model. For this purpose, the system reliability in the three different types of standby components, i.e., cold, warm and hot standby components, are calculated. Also, it is assumed that the stress and the strength components follow the Weibull distribution and the Weibull process, respectively. The maximum likelihood estimators of the redundancy system reliability are obtained. In addition, a simulation study is performed based on the Monte Carlo method. Finally, the results are illustrated via a practical example that is the time of successive failures of the air conditioning system of every member of a fleet of jet airplanes. [ABSTRACT FROM AUTHOR]

Traffic rules violations in urban areas, which can cause traffic crashes and unsafe situations, are a major issue nowadays. The present paper aims to analyze the frequency of traffic violations in Tehran city, Iran, over a five-year period (March 2016- March 2021). The data is obtained via road traffic violation monitoring system which can capture and process various traffic violations. This database, containing about 97 million violations committed by about 16 million drivers, is explored applying three statistical approaches. In the first approach, some multiplicative SARIMA and Bayesian Spatio-temporal models are fitted to the monthly violations. Also, in the second approach, the K-means clustering algorithm is applied to discover homogeneous districts of Tehran Municipality regarding their number of violations and their number of violations per camera towers meter during the study. Finally, in the third approach, a random-effect zero-truncated one-inflated Poisson model is proposed to study factors affecting driver's number of violations over time. [ABSTRACT FROM AUTHOR]

Two-variable sinusoidal shear and normal deformation theory is used in this paper for elastic analysis of doubly curved nanoshells resting on elastic foundation. Thickness stretching effect is accounted based on higher-order shear and normal deformation theory. The transverse displacement is decomposed into bending and stretching components based on two-variable sinusoidal shear deformation theory. Unlike classical structural theories for plates and shells, the present theory considers an extra variable as transverse displacement along the thickness direction. 3D constitutive relations are presented based on generalized Hooke's law. The principle of virtual work is used for derivation of governing equations and proper boundary conditions. An extensive parametric analysis is performed to present variation of in-plane and transverse displacements along the thickness direction in terms of the nonlocal parameter, opening angles and foundation characteristics. Comparison of results with and without thickness stretching effect show that the present theory improves results about 4% with respect to the structural theories without stretching effect. [ABSTRACT FROM AUTHOR]

This scoping review assesses the use of conditional cash transfer (CCT) interventions – direct distribution of money to individuals conditional on their compliance to certain requirements – in randomised controlled trials, quasi-experimental studies and large community-based randomised trials with health-focused outcomes. Five databases were searched to identify 68 records published 2004–2021 from 25 countries (8 low- (32%), 5 lower middle- (20%), 6 upper middle- (24%) and 6 high-income (24%), according to the World Bank Categorisation (2017). Forty-six studies were unique (after excluding multiple publications on a single study). The most common outcomes assessed were infectious diseases (30%); maternal health (24%); vaccination rates (17%); and childhood developmental measures (17%). The number of participants receiving CCT in each study ranged from 47 to 5,788, with a median of 487 individuals. The number of total participants ranged from 72 to 14,000, with a median of 1,289 individuals. Fifteen percent of studies involved mobile CCT disbursement. More than a quarter of payments were greater than 50 USD (29%), and most payments were 20 USD or less (58%). Seventy-eight percent of unique full-length studies reported statistically significant CCT effects. Although CCTs remain controversial, a growing evidence base is emerging for their potential impact in specific health conditions. [ABSTRACT FROM AUTHOR]

Textbooks provide the most serious source of knowledge construction and transmission for children at schools. This paper used a discursive and qualitative content analysis approach to extract the dominant values, ideologies and identities in four social studies textbooks taught nationwide to children in primary schools in Iran. Textual and visual analysis were applied on these textbooks and the results showed the saliency of four dominant discourses and values including pre-Islamic ethos and Iranian-Islamic identity, war and peace, social and traditional values in Iranian culture, and respect for diversity. Each of these discourses are discussed and some recommendations are made at the end of the paper to better situate the significance of these values in school textbooks. [ABSTRACT FROM AUTHOR]

Granular columns are widely used to enhance the bearing capacity of weak soil. The filling material of columns is generally stone, gravel or sand. The use of industrial wastes such as steel slag in civil engineering applications not only reduces environmental pollution, but also leads to cost benefits. So far, many studies have been done on the behaviour of granular columns with and without geosynthetic encasement under vertical loads; however, very limited studies were conducted on the behaviour of waste granular columns with and without geosynthetic encasement under lateral loads. Therefore, this study aims to evaluate the lateral load capacity of steel slag granular columns reinforced with geosynthetic using a large direct shear test apparatus. Results demonstrated that the use of steel slag column improved the lateral load capacity of soil. The use of geosynthetic encasement in floating steel slag column could significantly enhance both the peak and critical state shear strength. The results indicated the viability of using steel slag column as a soil reinforcement providing sustainable and technical benefits mainly when using geosynthetic reinforcement. [ABSTRACT FROM AUTHOR]

One common limitation faced in mode choice modeling is data imbalance. Mode choice models, such as logit models, may output biased estimations for alternatives with smaller shares and consequently have high prediction errors. Since accurate prediction of the less commonly used modes is important in some applications, such as predicting transit mode share in many auto-oriented American cities, it is essential to improve the prediction capability of logit models for those modes. Hence, this study applies an imbalanced learning technique and evaluates the prediction capability and interpretability of logit models under both balanced and imbalanced datasets using a case study for the City of Nashville, Tennessee. The results show that the proposed method improves the accuracy of the less commonly used modes and the mean absolute percentage error by 18% and 2%, respectively, while keeping the models interpretable. Finally, we provide some high-level guidelines for mode choice modeling with imbalanced data. [ABSTRACT FROM AUTHOR]

Brain lesions following stroke have been shown prevalently in CT/MRI, and it was confirmed that lesions usually are accompanied by cognitive deficits. Although previous studies have emphasized that BDNF Val66Met polymorphism had a substantial role in neurogenesis and synaptic plasticity, it remains unclear to what extent an interaction may be appeared between neuroimaging findings and Val66Met variants on different cognitive functions following stroke. In a case-control study the carriers of at least one Val allele (n = 56), were compared with the carriers of Met/Met homozygotes (n = 156) in order to find possible neuroimaging factors in relation to cognitive functions in a sample from the north of Iran. The third edition of Addenbrooke's Cognitive Examination (ACE-III) was used to determine the cognitive functions. There were interactive effects among Val66Met genotypes with dominant hemisphere lesions [F = 6.97, ή² = 0.03, p = 0.009], cerebral atrophy [F = 5.43, ή² = 0.03, p = 0.011] and number of lesions [F = 4.32, ή² = 0.04, p = 0.014], for visuospatial skills, memory, and attention functions respectively; implying that the effect of dominant hemisphere lesions, cerebral atrophy, and multiple lesions on cognitive functions have been modulated by Met/Met homozygosity. The destructive effect of Val/Met homozygosity on cognitive functions was shown to be exacerbated by dominant hemispheric lesions, cerebral atrophy, and multiple lesions following stroke. The findings of present research support our hypothesis that interaction of Val66Met variants with cerebral lesions is associated with cognitive dysfunctions in post stroke conditions; particularly through Met/Met homozygosity which act as a buffer mechanism against some CT/MRI pathological findings. [ABSTRACT FROM AUTHOR]

The appropriate treatment of cancers critically depends on the precise identification of the tumor types. The Magnetic Resonance Imaging (MRI) provides a non-invasive approach for detecting the tumors and classifying their types. Computer-aided diagnosis (CAD) systems using image analysis and machine learning algorithms assist radiologists in making error-free decisions. This paper presents an integrated approach for the segmentation and classification of three types of brain tumors (i.e. meningioma, glioma, and pituitary tumor) in real MRI images. First, the images quality is enhanced by removing the noises using wiener and median filters. Then, the support vector machine (SVM) classifier is performed to segment the MR image. Following this, 42 features are extracted, among which eleven most practical features are chosen by the Differential Evolution (DE). Using the selected features, tumor slices are categorized using the k-nearest neighbors (KNN), the weighted kernel width SVM (WSVM) and the histogram intersection kernel SVM (HIK-SVM) classifiers. Afterwards, these classifiers are combined using a multi-objective differential evolution (MODE)-based ensemble technique to attain the classification accuracy of 92.46%, evaluated using the five-fold cross validation method. The results of the proposed approach are also compared with the experienced radiologist ground truth which shows that the proposed MODE-based ensemble technique is able to achieve high classification scores, measured also by sensitivity and specificity indices. [ABSTRACT FROM AUTHOR]

SARS-CoV-2 non-structural protein 1 (Nsp1) is a virulence factor that inhibits the translation of host mRNAs and interacts with viral RNA. To date, hundreds of mutations (base substitutions, deletions, and insertions) have been reported in SARS-CoV-2 Nsp1. Despite the relevance of Nsp1, a few studies have been conducted to understand the effect of those mutations on Nsp1 structure and function. In this study, the effects of the most frequent mutations were investigated using molecular dynamics simulations. We found that several mutations profoundly affect the local intrinsic disorder predisposition, with most deletions increasing disorder propensity and replacement mutations inducing variable effects. We found that deletions Δ80–90 and Δ156–158 destabilise the protein structure. For example, the Δ156–158 cause a higher root-mean-square deviation (RMSD) and Rg values than those of the wild-type of SARS-CoV-2 Nsp1. We also found that the SARS-CoV-2 Nsp1 is slightly more disordered than its counterpart from SARS-CoV. A better understanding of the complexity and dynamic nature of interactions between intrinsically disordered segments of Nsp1 and ribosome subunits might help develop novel therapeutic countermeasures against the SARS-CoV-2 variants. Highlights Multiple mutations have been found in the N/C-termini of the SARS-CoV-2 Nsp1. The effects of deletions are greater than substitutions on SARS-CoV-2 Nsp1. Δ80–90 and Δ156–158 destabilise the protein structure and may increase the SARS-CoV-2 virulence. F157S, E159D, L173P, and R175H mutations affect the structure of the SARS-CoV-2 Nsp1 and may cause increased infectivity. The most disorder-promoting mutations were F157L and M174 K, whereas E159D and E159 K were the most order-promoting. [ABSTRACT FROM AUTHOR]