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1.
Nat Comput Sci ; 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38783137

RESUMEN

In the post-Moore's law era, the progress of electronics relies on discovering superior semiconductor materials and optimizing device fabrication. Computational methods, augmented by emerging data-driven strategies, offer a promising alternative to the traditional trial-and-error approach. In this Perspective, we highlight data-driven computational frameworks for enhancing semiconductor discovery and device development by elaborating on their advances in exploring the materials design space, predicting semiconductor properties and optimizing device fabrication, with a concluding discussion on the challenges and opportunities in these areas.

2.
Int Urol Nephrol ; 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38549000

RESUMEN

INTRODUCTION: Ureteropelvic junction obstruction (UPJO) is a commonly encountered abnormality and it can lead to serious consequences such as renal dysplasia eventually resulting in loss of kidney. Hence, early diagnosis and timely management remains the cornerstone of the treatment. The most anticipated technique amongst modern day urologist is the robot-assisted laparoscopic pyeloplasty (RALP). The study aims to determine early post-operative outcomes of robot-assisted laparoscopic transperitoneal pyeloplasty procedure in patients presenting with unilateral ureteropelvic junction obstruction to establish the local perspective. METHODOLOGY: This is a descriptive study involving patients with ureteropelvic junction obstruction in a tertiary care facility in Karachi; Sindh Institute of Urology and Transplant (SIUT). A total of 46 participants were recruited. Robot-assisted laparoscopic transperitoneal dismembered Hynes-Anderson pyeloplasty was performed by a single surgeon with over 3 years of experience in the presence of the researcher. Early postoperative outcome total operative time, length of hospital stay, console time and blood loss were noted by the researcher as per operational definition. Data were analyzed on SPSS Version 22. RESULTS: Mean age in our study was 46.51 years with the standard deviation of ± 10.87. Whereas, mean length of hospital stay, total operative time, total blood loss, console time, pre-hemoglobin, posthemoglobin, height, weight and BMI in our study was 1.19 ± 0.40 days, 64.58 ± 17.59 min, 9.56 ± 6.13 ml, 30.17 ± 4.99 min, 12.66 ± 1.47 ml, 11.79 ± 1.93 ml, 165.62 ± 8.23 cm, 68.34 ± 8.23 kg and 24.85 ± 3.34 kg/m2, respectively. CONCLUSION: Recent advancements in technology have yielded the latest RALP technique which has been proven significantly better than existing approaches and similar results are reported by this study demonstrating improvement in peri-operative and post-operative outcomes ultimately ameliorating the quality of life of patients with UPJO.

3.
Molecules ; 29(6)2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38542903

RESUMEN

Shape memory and self-healing polymer nanocomposites have attracted considerable attention due to their modifiable properties and promising applications. The incorporation of nanomaterials (polypyrrole, carboxyl methyl cellulose, carbon nanotubes, titania nanotubes, graphene, graphene oxide, mesoporous silica) into these polymers has significantly enhanced their performance, opening up new avenues for diverse applications. The self-healing capability in polymer nanocomposites depends on several factors, including heat, quadruple hydrogen bonding, π-π stacking, Diels-Alder reactions, and metal-ligand coordination, which collectively govern the interactions within the composite materials. Among possible interactions, only quadruple hydrogen bonding between composite constituents has been shown to be effective in facilitating self-healing at approximately room temperature. Conversely, thermo-responsive self-healing and shape memory polymer nanocomposites require elevated temperatures to initiate the healing and recovery processes. Thermo-responsive (TRSMPs), light-actuated, magnetically actuated, and Electrically actuated Shape Memory Polymer Nanocomposite are discussed. This paper provides a comprehensive overview of the different types of interactions involved in SMP and SHP nanocomposites and examines their behavior at both room temperature and elevated temperature conditions, along with their biomedical applications. Among many applications of SMPs, special attention has been given to biomedical (drug delivery, orthodontics, tissue engineering, orthopedics, endovascular surgery), aerospace (hinges, space deployable structures, morphing aircrafts), textile (breathable fabrics, reinforced fabrics, self-healing electromagnetic interference shielding fabrics), sensor, electrical (triboelectric nanogenerators, information energy storage devices), electronic, paint and self-healing coating, and construction material (polymer cement composites) applications.

4.
J Mol Graph Model ; 129: 108729, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38479238

RESUMEN

The recent discovery of superconductivity behavior in the mother BiS2-layered compounds has captivated the attention of several physicists. The crystal structure of superconductors with alternate layers of BiS2 is homologous to that of cuprates and Fe-based superconductors. The full-potential linearized augmented plane-wave (FP-LAPW) technique was utilized to investigate the electronic structures and density of states in the vicinity of the Fermi energy of SrFBiS2 and BaFBiS2 compounds under the electron carriers doping. The introduction of electron doping (carries doping) reveals that the host compounds SrFBiS2 and BaFBiS2 exhibit features indicative of superconductivity. This carrier doping of SrFBiS2 and BaFBiS2 compounds (electron-doped) has a significant impact on the lowest conduction states near the Fermi level for the emergence of the superconducting aspect. The electron doping modifies and induces changes in the electronic structures with superconducting behavior in (Ae)1.7FBiS2(Ae=Sr,Ba) compounds. A Fermi surface nesting occurred under the modification of electrons (carriers) doping in the host compounds SrFBiS2 and BaFBiS2. Furthermore, the optical characteristics of the carrier-doped SrFBiS2 and BaFBiS2 compounds are simulated. Due to the anisotropic behavior, the optical properties of these materials based on BiS2 demonstrate a pronounced polarization dependency. The starting point at zero photon energy in the infrared region is elucidated by considering the Drude features in the optical conductivity spectra of SrFBiS2 and BaFBiS2 compounds, when the electron carriers doping is applied. It was clearly noticed that the spin-orbit coupling (SOC) influences the electronic band structures, density of states, Femi surface, and optical features because of the heavy Bismuth atom, which may disclose fascinating aspects. Further, we conducted simulations to assess the thermoelectric properties of these mother compounds. The two BiS2-layered compounds could be suitable for practical thermoelectric purposes and are highlighted through assessment of electrical conductivity, thermal conductivity, Seebeck coefficient, and power factor. As a result, we propose that the mechanisms of superconducting behavior in BiS2 family may pave new avenues for investigating the field of unconventional superconductivity. It may also provide new insights into the origin of high-Tc superconductivity nature.


Asunto(s)
Bismuto , Electrónica , Conductividad Eléctrica , Anisotropía , Electrones
5.
Adv Sci (Weinh) ; : e2400258, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38526197

RESUMEN

Due to their amorphous-like ultralow lattice thermal conductivity both below and above the superionic phase transition, crystalline Cu- and Ag-based superionic argyrodites have garnered widespread attention as promising thermoelectric materials. However, despite their intriguing properties, quantifying their lattice thermal conductivities and a comprehensive understanding of the microscopic dynamics that drive these extraordinary properties are still lacking. Here, an integrated experimental and theoretical approach is adopted to reveal the presence of Cu-dominated low-energy optical phonons in the Cu-based argyrodite Cu7PS6. These phonons yield strong acoustic-optical phonon scattering through avoided crossing, enabling ultralow lattice thermal conductivity. The Unified Theory of thermal transport is employed to analyze heat conduction and successfully reproduce the experimental amorphous-like ultralow lattice thermal conductivities, ranging from 0.43 to 0.58 W m-1 K-1, in the temperature range of 100-400 K. The study reveals that the amorphous-like ultralow thermal conductivity of Cu7PS6 stems from a significantly dominant wave-like conduction mechanism. Moreover, the simulations elucidate the wave-like thermal transport mainly results from the contribution of Cu-associated low-energy overlapping optical phonons. This study highlights the crucial role of low-energy and overlapping optical modes in facilitating amorphous-like ultralow thermal transport, providing a thorough understanding of the underlying complex dynamics of argyrodites.

6.
ACS Appl Mater Interfaces ; 16(8): 10104-10115, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38361321

RESUMEN

Hierarchical porous nanowire-like MoS2/CoNiO2 nanohybrids were synthesized via the hydrothermal process. CoNiO2 nanowires were selected due to the edge site, high surface/volume ratio, and superior electrochemical characteristics as the porous backbone for decoration of layered MoS2 nanoflakes to construct innovative structure hierarchical three-dimensional (3D) porous NWs MoS2/CoNiO2 hybrids with excellent charge accumulation and efficient ion transport capabilities. Physicochemical analyses were conducted on the developed hybrid composite, revealing conclusive evidence that the CoNiO2 nanowires have been securely anchored onto the surface of the MoS2 nanoflake array. The electrochemical results strongly proved the benefit of the hierarchical 3D porous MoS2/CoNiO2 hybrid structure for the charge storage kinetics. The synergistic characteristics arising from the MoS2/CoNiO2 composite yielded a notably high specific capacitance of 1340 F/g at a current density of 0.5 A/g. Furthermore, the material exhibited sustained cycling stability, retaining 95.6% of its initial capacitance after 10 000 long cycles. The asymmetric device comprising porous MoS2/CoNiO2//activated carbon encompassed outstanding energy density (93.02 Wh/kg at 0.85 kW/kg) and cycling stability (94.1% capacitance retention after 10 000 cycles). Additionally, the successful illumination of light-emitting diodes underscores the significant potential of the synthesized MoS2/CoNiO2 (2D/1D) hybrid for practical high-energy storage applications.

7.
Curr Protoc ; 4(2): e989, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38363064

RESUMEN

Acne vulgaris (acne) effects nearly 90% of all Western teenagers, and the only pharmaceutical class of agents to treat severe forms of this skin condition are the retinoids, which are well-described teratogens. Yet about 50% of the patients receiving this class of therapeutics are women of child-bearing age, in their peak years of reproductive potential. On this basis, there is a significant unmet medical need for agents to treat severe forms of acne that do not carry this liability. As a means to assess potential agents of this type, here we describe methods for estimating the relative amount of sebum that a mouse produces based on the water retention on fur following a thorough wetting procedure. We have shown that a compound that is clinically effective in reducing sebum production demonstrates activity in this model. The method is therefore useful for evaluating therapeutic candidates for reducing sebum production, which would in turn be useful for treating acne. We have broken the entire procedure down into two phases/two protocols, as listed below. © 2024 Wiley Periodicals LLC. Basic Protocol 1: Pre-wash wet weight measurement Basic Protocol 2: Post-wash wet-weight measurement.


Asunto(s)
Acné Vulgar , Sebo , Adolescente , Humanos , Femenino , Ratones , Animales , Masculino , Modelos Animales de Enfermedad , Acné Vulgar/tratamiento farmacológico , Retinoides/uso terapéutico , Equilibrio Hidroelectrolítico
8.
J Appl Genet ; 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38261266

RESUMEN

Enalapril is an orally administered angiotensin-converting enzyme inhibitor which is widely prescribed to treat hypertension, chronic kidney disease, and heart failure. It is an ester prodrug that needs to be activated by carboxylesterase 1 (CES1). CES1 is a hepatic hydrolase that in vivo biotransforms enalapril to its active form enalaprilat in order to produce its desired pharmacological impact. Several single nucleotide polymorphisms in CES1 gene are reported to alter the catalytic activity of CES1 enzyme and influence enalapril metabolism. G143E, L40T, G142E, G147C, Y170D, and R171C can completely block the enalapril metabolism. Some polymorphisms like Q169P, E220G, and D269fs do not completely block the CES1 function; however, they reduce the catalytic activity of CES1 enzyme. The prevalence of these polymorphisms is not the same among all populations which necessitate to consider the genetic panel of respective population before prescribing enalapril. These genetic variations are also responsible for interindividual variability of CES1 enzyme activity which ultimately affects the pharmacokinetics and pharmacodynamics of enalapril. The current review summarizes the CES1 polymorphisms which influence the enalapril metabolism and efficacy. The structure of CES1 catalytic domain and important amino acids impacting the catalytic activity of CES1 enzyme are also discussed. This review also highlights the importance of pharmacogenomics in personalized medicine.

9.
Phys Chem Chem Phys ; 26(4): 3614-3622, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38223943

RESUMEN

Over the past decade, perovskites have received considerable attention because of their record power conversion efficiency (25.7%) in solar cells. These materials have also received recent research interest in thermoelectrics, most likely due to their high carrier mobility, large power factor, and ultralow thermal conductivity. Therefore, in the present work, we have examined the optoelectronic and thermoelectric properties of A2NaIO6 (A = Ca, Sr) double perovskites using first-principles calculations. Stability has been confirmed using reliable and accurate descriptors of formation energy and phonon calculations. The optimized lattice constant and volume show an increasing tendency with changing A site cation (Ca → Sr). The computed band structures depict the semiconducting nature with direct band gap values of 2.64 eV (Ca2NaIO6) and 2.48 eV (Sr2NaIO6). The absorption was found to start in the visible range where the reflectivity was less than 10%. Moreover, the high Seebeck coefficient, large electrical conductivity, and fairly low thermal conductivity result in ZT values of 0.724 for Ca2NaIO6 and 0.686 for Sr2NaIO6 at 1000 K. With their optimum band gap, excellent light absorption capacity, and high ZT values, A2NaIO6 emerge as promising candidates for optoelectronic and thermoelectric applications.

10.
Nanoscale ; 16(6): 2913-2922, 2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38247404

RESUMEN

Moiré superlattices (MSLs) in twisted two-dimensional van der Waals materials feature twist-angle-dependent crystal symmetry and strong optical nonlinearities. By adjusting the twist angle in bilayer van der Waals materials, the second-harmonic generation (SHG) can be controlled. Here, we focus on exploring the electronic and SHG properties of MSLs in 2D bilayer transition metal dichalcogenides (TMDs) with different twist angles through first-principles calculations. We constructed MSL structures of five TMD materials, including three single-phase materials (MoS2, WS2, and MoSe2) and two heterojunctions (MoS2/MoSe2 and MoS2/WS2) with twist angles of 9.4°, 13.2°, 21.8°, 32.2°, and 42.1° without lattice mismatch. Our findings demonstrate a consistent variation in the SHG susceptibility among different TMD MSLs as a response to twist-angle changes. The underlying reason for the twist-angle dependence of SHG is that the twist angle regulates the interlayer coupling strength, affecting the optical band gap of MSLs and subsequently tuning the SHG susceptibility. Through a comparison of the static SHG susceptibility values, we identified the twist angle of 9.4° as the configuration that yields the highest SHG susceptibility (e.g. 358.5 pm V-1 for the 9.4° MoSe2 MSL). This value is even twice that of the monolayer (173.3 pm V-1 for monolayer MoSe2) and AA'-stacked bilayer structures (139.8 pm V-1 for AA' MoSe2). This high SHG susceptibility is attributed to the strong interlayer coupling in the 9.4° MSL, which enhances the valence band energy (contributed by the antibonding orbitals of chalcogen-pz and transition metal-dz2) and consequently leads to a small optical band gap, thus improving the optical transitions. The findings of this study provide a straightforward way to improve the SHG performance of bilayer TMDs and also throw light on the sensitive relationship between the twist angle, band structure and SHG properties of TMD MSLs.

11.
Surg Innov ; 31(1): 26-32, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37926929

RESUMEN

INTRODUCTION: Cholelithiasis is one of the most common diseases encountered in gastroenterology. Laparoscopic cholecystectomy can be labelled as difficult if the surgery continues for more than 60 minutes or if the cystic artery is injured before ligation or clipping. Predicting difficult laparoscopic cholecystectomy can help the surgeon to be prepared for intraoperative challenges such as adhesions in triangle of Calot, injury to cystic artery or gall stone spillage; and improve patient counseling. METHODS: In this cross-sectional study, we evaluated 269 patients with diagnosed cholelithiasis and planned for laparoscopic cholecystectomy in the general surgery department of Civil Hospital Karachi. After approval of the institution review board of the Civil Hospital, the data of all the patients was collected along with informed consent. The patients were selected via nonprobability, consecutive sampling. RESULTS: The prevalence of difficult LC during procedure was 14.5% (39/269). Contingency table showed the true positive, negative and false positive and negative observation and using these observation to compute accuracy. Sensitivity, specificity, PPV, NPV and accuracy of serum c-reactive protein (CRP) in predicting the difficult laparoscopic cholecystectomy in patients of cholelithiasis was 87.2%, 97%, 82.9%, 97.8% and 95.5% respectively. Effect modifiers like age, gender and BMI were controlled by stratification analysis and observed that diagnostic accuracy was above 90% in all stratified groups as presented in the following tables. 175 (65.06%) of 279 patients were females indicating female predominance. In general, 41 patients (15.05%) had CRP serum levels greater than 11 mg/dL out of which 34 patients had to undergo difficult laparoscopic cholecystectomy (DLC), while 223 out of 228 patients with serum CRP levels of less than 11 mg/dL did not face any difficulty during their cholecystectomy. Similar results have been acquired across all age groups and both genders. CONCLUSION: C Reactive Protein is a potent predictor of difficult laparoscopic cholecystectomy and its conversion preoperatively. Patients with preoperatively high C Reactive Protein CRP levels in serum have more chances of complication intraoperatively and increased chances of conversion from laparoscopic to open surgery. Preoperative C Reactive Protein (CRP) with values >11 mg/dL was associated with the highest odds of presenting difficult laparoscopic cholecystectomy (DLC) in our study. This value possesses good sensitivity, specificity, PPV, and NPV for predicting DLC in our population.


Asunto(s)
Colecistectomía Laparoscópica , Cálculos Biliares , Humanos , Femenino , Masculino , Colecistectomía Laparoscópica/efectos adversos , Colecistectomía Laparoscópica/métodos , Proteína C-Reactiva/análisis , Estudios Transversales , Colecistectomía , Cálculos Biliares/cirugía
13.
Open Vet J ; 13(11): 1425-1435, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38107225

RESUMEN

Background: Feed additives that increase nutrient availability in feeds have gained a lot of interest. Aim: An experiment was conducted to determine whether amylase, protease, and their combined supplementation affected broiler performance. Methods: Two hundred eighty broiler chicks were selected and distributed randomly into 28 replicate pens with four treatment groups and seven replicates under a completely randomized design. A total of four diets were developed, having 0, 100, 100, and 100 + 100 g of control (AP0), amylase (A1), protease (P1), and amylase + protease (AP1)/ton of feed, respectively. Four replicates of each treatment were fed each diet. Each diet was randomly allotted to each group. Ad-libitum feeding was provided to the birds. The feeding program had starter and finisher diets. Upon completion of the experiment, three birds from each pen were slaughtered to analyze the carcass characteristics and organ weight. Results: Differences were insignificant between 100 g/ton of amylase supplementation and FI, body weight gain (BWG), or feed conversion ratio (FCR) (p > 0.05). Supplementation with 10 0g/ton of protease did not significantly affect FI, BWG, and FCR (p > 0.05). Similarly, 100 + 100 g/ton of amylase + protease addition had no significant effect on FI, BWG, and FCR (p > 0.05). None of the treatments significantly affected carcass weight, abdominal fat percentage, dressing percentage, drumstick, wings, breast, and thigh weights (p > 0.05). In addition, there were no significant effects (p > 0.05) on the weight of the heart, liver, gizzard, and spleen. Conclusion: In conclusion, amylase, protease, and their combined supplementation at a rate of 100 g/ton of feed did not influence BWG, FI, FCR, carcass characteristics, or organ weight.


Asunto(s)
Amilasas , Pollos , Animales , Dieta/veterinaria , Suplementos Dietéticos , Péptido Hidrolasas/farmacología
14.
Nanomaterials (Basel) ; 13(24)2023 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-38133053

RESUMEN

A solid-solution cathode of LiCoPO4-LiNiPO4 was investigated as a potential candidate for use with the Li4Ti5O12 (LTO) anode in Li-ion batteries. A pre-synthesized nickel-cobalt hydroxide precursor is mixed with lithium and phosphate sources by wet ball milling, which results in the final product, LiNiyCo1-yPO4 (LNCP) by subsequent heat treatment. Crystal structure and morphology of the product were analyzed by X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). Its XRD patterns show that LNCP is primarily a single-phase compound and has olivine-type XRD patterns similar to its parent compounds, LiCoPO4 and LiNiPO4. Synchrotron X-ray absorption spectroscopy (XAS) analysis, however, indicates that Ni doping in LiCoPO4 is unfavorable because Ni2+ is not actively involved in the electrochemical reaction. Consequently, it reduces the charge storage capability of the LNCP cathode. Additionally, ex situ XRD analysis of cycled electrodes confirms the formation of the electrochemically inactive rock salt-type NiO phase. The discharge capacity of the LNCP cathode is entirely associated with the Co3+/Co2+ redox couple. The electrochemical evaluation demonstrated that the LNCP cathode paired with the LTO anode produced a 3.12 V battery with an energy density of 184 Wh kg-1 based on the cathode mass.

15.
RSC Adv ; 13(44): 30838-30854, 2023 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-37869397

RESUMEN

In this article, ZnO:NiO:CuO nanocomposites (NCPs) were synthesized using a hydrothermal method, with different Zn : Ni : Cu molar ratios (1 : 1 : 1, 2 : 1 : 1, 1 : 2 : 1, and 1 : 1 : 1). The PXRD confirmed the formation of a NCP consisting of ZnO (hexagonal), NiO (cubic), and CuO (monoclinic) structures. The crystallite sizes of NCPs were calculated using Debye Scherrer and Williamson-Hall methods. The calculated crystalline sizes (Scherrer method) of the NCPs were determined to be 21, 27, 23, and 20 nm for the molar ratios 1 : 1 : 1, 2 : 1 : 1, 1 : 2 : 1, and 1 : 1 : 2, respectively. FTIR spectra confirmed the successful formation of heterojunction NCPs via the presence of metal-oxygen bonds. The UV-vis spectroscopy was used to calculate the bandgap of synthesized samples and was found in the range of 2.99-2.17 eV. SEM images showed the mixed morphology of NCPs i.e., irregular spherical and rod-like structures. The dielectric properties, including AC conductivity, dielectric constant, impedance, and dielectric loss parameters were measured using an LCR meter. The DC electrical measurements revealed that NCPs have a high electrical conductivity. All the NCPs were evaluated for the photocatalytic degradation of Methylene blue (MB), methyl orange (MO), and a mixture of both of these dyes. The NCPs with a molar ratio 1 : 1 : 2 (Zn : Ni : Cu) displayed outstanding photocatalytic activity under sunlight, achieving the degradation efficiency of 98% for methylene blue (MB), 92% for methyl orange (MO) and more than 87% in the case of a mixture of dyes within just 90 minutes of illumination. The antibacterial activity results showed the more noxious nature of NCPs against Gram-negative bacteria with a maximum zone of inhibition revealed by the NCPs of molar ratio 1 : 2 : 1 (Zn : Ni : Cu). On the basis of these observations, it can be anticipated that the NCPs can be successfully employed for the purification of contaminated water by the degradation of hazardous organic compounds and in antibacterial ointments.

16.
Cureus ; 15(6): e40444, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37456424

RESUMEN

Background The most important factor in combating the coronavirus disease 2019 (COVID-19) pandemic was the provision of safe and effective vaccines. The acceptance of vaccines is impacted by several variables, including beliefs about the vaccine's safety and adverse effects. Vaccine side effects can vary depending on the type, but they are often moderate, localized, transient, and self-limiting. Therefore, this study aimed to assess the prevalence of side effects experienced after receiving the Sinovac vaccine by participants hypertensive and non-hypertensive participants. Methodology This was a cross-sectional, multicenter study that was performed using non-probability sampling. The study duration was six months from May 1, 2022, to October 31, 2022. The study involved 600 individuals who had either received the first or second dose of the Sinovac vaccine. For categorical data, frequencies and percentages were documented. The chi-square test was applied to determine the association between local and systemic side effects among hypertensive and non-hypertensive participants. Results The study findings showed that out of 600 participants, there were 187 (62.3%) males and 113 (37.7%) females with hypertension, and 222 (74.0%) males and 78 (26.0%) females without hypertension, with a significant association (p = 0.002). Following the first dose of the Sinovac vaccine, fever was the most commonly reported side effect in 153 (51.0%) hypertensive participants and 62 (20.7%) non-hypertensive participants, with a significant association (p < 0.001). Similarly, following the second dose of the Sinovac vaccine, fever was the most commonly reported side effect in 108 (36.0%) hypertensive participants and 57 (19.0%) non-hypertensive participants, with a significant association (p < 0.001). Conclusions This study concluded that the presence of hypertension significantly increased the manifestations of local and systemic side effects compared with non-hypertensive participants. Moreover, fever, pain, and swelling at the injection site were the most commonly reported side effects after receiving the first and second doses of the Sinovac vaccine.

17.
Heliyon ; 9(7): e17641, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37455960

RESUMEN

The flow of fluid over a spinning disk has a broad scope of numerous applications. It is employed in various things, including medical equipment, the braking system of cars, gas turbines, plastic films, and glass production. As a result of these applications, we considered the phenomena of Darcy Forchheimer's three-dimensional flow on TiO2-Fe3O4 nanoparticles suspended in based CMC-water fluid. The influence of thermal radiation and convective conditions is studied. Moreover, the Buongiorno model is utilized to compute the Brownian motion and the thermophoretic effect. To generate the non-dimensionalized governing equations, suitable alterations are put into use. These equations are then utilized with Matlab BVP4c. Graphs are used to analyze the behavior of velocity distributions, and thermal and concentration profiles at different parameter values. In addition, the solutions to the flow problem have been analyzed in terms of several other physical variables on velocity, temperature, concentration, drag force, heat, and mass transfer. According to the findings, it is clear that an escalates in the value of the rotation parameter leads to an increase in the radial velocity and axial velocity. In contrast, an opposite pattern is followed in the Forchheimer number. Finally, some engineering quantities are evaluated numerically and presented in tabular forms.

18.
Materials (Basel) ; 16(11)2023 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-37297284

RESUMEN

The additive manufacturing of concrete, also known as 3D-printed concrete, is produced layer by layer using a 3D printer. The three-dimensional printing of concrete offers several benefits compared to conventional concrete construction, such as reduced labor costs and wastage of materials. It can also be used to build complex structures with high precision and accuracy. However, optimizing the mix design of 3D-printed concrete is challenging, involving numerous factors and extensive hit-and-trail experimentation. This study addresses this issue by developing predictive models, such as the Gaussian Process Regression model, Decision Tree Regression model, Support Vector Machine model, and XGBoost Regression models. The input parameters were water (Kg/m3), cement (Kg/m3), silica fume (Kg/m3), fly ash (Kg/m3), coarse aggregate (Kg/m3 & mm for diameter), fine aggregate (Kg/m3 & mm for diameter), viscosity modifying agent (Kg/m3), fibers (Kg/m3), fiber properties (mm for diameter and MPa for strength), print speed (mm/sec), and nozzle area (mm2), while target properties were the flexural and tensile strength of concrete (MPa data from 25 literature studies were collected. The water/binder ratio used in the dataset ranged from 0.27 to 0.67. Different types of sands and fibers have been used, with fibers having a maximum length of 23 mm. Based upon the Coefficient of Determination (R2), Root Mean Square Error (RMSE), Mean Square Error (MSE), and Mean Absolute Error (MAE) for casted and printed concrete, the SVM model performed better than other models. All models' cast and printed flexural strength values were also correlated. The model's performance has also been checked on six different mix proportions from the dataset to show its accuracy. It is worth noting that the lack of ML-based predictive models for the flexural and tensile properties of 3D-printed concrete in the literature makes this study a novel innovation in the field. This model could reduce the computational and experimental effort required to formulate the mixed design of printed concrete.

19.
J Comput Chem ; 44(19): 1690-1703, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37093704

RESUMEN

In this study, structural, electronic, optical, thermoelectric, and thermodynamics properties of vacancy-ordered double perovskites Rb2 XCl6 (X = Se, Ti) were explored theoretically. The results revealed that Rb2SeCl6 and Rb2 TiCl6 are indirect band gap (Eg ) semiconductors with Eg values of 2.95 eV, and 2.84 eV respectively. The calculated properties (phonons, elastic constant, Poisson's ratio, and Pugh's ratio) revealed that both materials are dynamically and chemically stable and can exhibit brittle (Rb2 SeCl6 ) and ductile (Rb2 TiCl6 ) nature. From the analysis of optical parameters, it was noticed that the refractive index of the materials has a value of 1.5-2.0 where light absorption was found from the visible to the ultraviolet region. The thermoelectric properties determined by using the BoltzTrap code demonstrated that at room temperature, the Figure of merit (ZT) was found to be 0.74 and 0.76 for Rb2 SeCl6 and Rb2 TiCl6 , respectively. Despite a moderate value of ZT in such materials, further studies might explore effective methods for tuning the electronic band gap and improving the thermoelectric response of the material for practical energy production applications.


Asunto(s)
Compuestos Inorgánicos , Titanio , Compuestos de Calcio , Óxidos
20.
Small ; 19(8): e2205881, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36504329

RESUMEN

Two-dimensional layered transition metal dichalcogenides have emerged as promising materials for supercapacitors and hydrogen evolution reaction (HER) applications. Herein, the molybdenum sulfide (MoS2 )@vanadium sulfide (VS2 ) and tungsten sulfide (WS2 )@VS2  hybrid nano-architectures prepared via a facile one-step hydrothermal approach is reported. Hierarchical hybrids lead to rich exposed active edge sites, tuned porous nanopetals-decorated morphologies, and high intrinsic activity owing to the strong interfacial interaction between the two materials. Fabricated supercapacitors using MoS2 @VS2  and WS2 @VS2  electrodes exhibit high specific capacitances of 513 and 615 F g- 1 , respectively, at an applied current of 2.5 A g- 1  by the three-electrode configuration. The asymmetric device fabricated using WS2 @VS2  electrode exhibits a high specific capacitance of 222 F g- 1  at an applied current of 2.5 A g- 1  with the specific energy of 52 Wh kg- 1  at a specific power of 1 kW kg- 1 . For HER, the WS2 @VS2  catalyst shows noble characteristics with an overpotential of 56 mV to yield 10 mA cm- 2 , a Tafel slope of 39 mV dec-1 , and an exchange current density of 1.73 mA cm- 2 . In addition, density functional theory calculations are used to evaluate the durable heterostructure formation and adsorption of hydrogen atom on the various accessible sites of MoS2 @VS2  and WS2 @VS2  heterostructures.

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