bluuebunny/crossref_metadata_2025 huggingface dataset:
Allopurinol for Secondary Prevention in Patients with Cardiovascular Disease: A Systematic Review and Meta-Analysis of Randomized Controlled Trials
Authors: Ye Yuyang , Liao Guangzhi , Liu Ting , Hu Xinru , Chen Xuefeng , Bai Lin , Peng Yong
Published: September 2023

Background: The effects of allopurinol in patients with cardiovascular disease are not well defined; therefore, the latest evidence is summarized in this study. Methods: PubMed, Embase, Cochrane Library, and ClinicalTrials.gov databases were searched for randomized controlled trials (RCTs) of allopurinol in patients with cardiovascular disease published up to 11 February 2023. The primary outcome was cardiovascular death. Results: We combined the results of 21 RCTs that included 22,806 patients. Compared to placebo/usual care, allopurinol treatment was not associated with a significant reduction in cardiovascular death (RR 0.60; 95% CI 0.33–1.11) or all-cause death (RR 0.90; 95% CI 0.72–1.12). However, evidence from earlier trials and studies with small sample sizes indicated that allopurinol might confer a protective effect in decreasing cardiovascular death (RR 0.34; 95% CI 0.15–0.76) across patients undergoing coronary artery bypass grafting (CABG) or having acute coronary syndrome (ACS). In comparisons between allopurinol and febuxostat, we observed no difference in cardiovascular death (RR 0.92; 95% CI 0.69–1.24) or all-cause death (RR 1.02; 95% CI 0.75–1.38). Conclusion: Allopurinol could not reduce cardiovascular (CV) death or major adverse CV outcomes significantly in patients with existing cardiovascular diseases. Given the limitations of the original studies, the potential advantages of allopurinol observed in patients undergoing CABG or presenting with ACS necessitate further confirmation through subsequent RCTs. In the comparisons between allopurinol and febuxostat, our analysis failed to uncover any marked superiority of allopurinol in reducing the risk of adverse cardiovascular incidents.
Feasibility Study on Production of High-Purity Rhenium-185 by Nuclear Transmutation of Natural Tantalum
Authors: Tanoue Yuki , Yokoyama Tsugio , Ozawa Masaki
Published: September 2023

Rhenium-186 (Re-186) has attracted attention as a medical isotope. The feasibility of producing Re-185, the raw material for Re-186, using a fast reactor was evaluated using a continuous energy Monte Carlo code. The irradiation of natural tantalum (Ta) in the fast reactor can produce Re-185 with an isotopic purity of 99%. A two-step irradiation process with different moderators was found to improve the production rate of Re-185. Specifically, this can be achieved by using zirconium hydride (ZrH1.7) as a moderator in the first transmutation process from natural Ta to tungsten (W), and then zirconium deuteride (ZrD1.7) as a moderator in the second transmutation process from W to Re-185. Due to the two-step irradiation, the production rate of Re-185 from Ta can be increased up to a maximum of 470 times compared with irradiation without a moderator, and 2.3 g of Re-185 can be obtained from 1571 g of Ta in 1 year of irradiation. The proposed isotope production method is a new method that is different from the conventional electromagnetic enrichment process.
Investigation of the Pozzolanic Activity Improvement of Yellow Phosphorus Slag with Thermal Activation
Authors: Liu Xinyue , Liu Xiaoming , Zhang Zengqi , Wei Chao , Zeng Qingsen , Li Yantian , Ma Shanliang
Published: September 2023

Yellow phosphorus slag (YPS) is a byproduct from the production of yellow phosphorus. It has potential pozzolanic activity and can be used as a supplementary cementitious material. However, the early strength of cement mortar decreases significantly with increasing YPS dosage, which restricts the utilization of YPS in cement and concrete. This study aimed to increase the pozzolanic activity of YPS ash by thermal activation. The strength method, alkali dissolution method and polymerization degree method were used to evaluate the effect of thermal activation at different temperatures on the pozzolanic activity of YPS ash. The results showed that YPS ash calcined at 800 °C helps to enhance the early strength because the fluorine in cuspidine (Ca4Si2O7F2) is insoluble, reducing the retarding effect on the mortar. The higher late strength of YPS ash calcined at 100 °C was due to the low polymerization degree of [SiO4]. The pozzolanic activity of YPS ash is positively correlated with the dissolution concentration of (Si + Al) and the compressive strength and negatively associated with the polymerization degree. This paper shows a possibility for the large-scale utilization of YPS.
Preparation of High-Ductility Cement-Calcined Coal-Gangue-Powder-Composite-Based Rapid Repair Material
Authors: Ren Biaokun , Chai Lijuan , Liu Yuanzhen , Wang Yangkai
Published: September 2023

Coal gangue is a kind of solid waste. A high-ductility cement-calcined coal-gangue-powder-composite-based rapid repair material (HD-RRM) was prepared by partially replacing cement with calcined coal gangue powder (CCGP) for achieving high ductility and rapid hardening and conforming to the strength requirements of pavement layers. First, the physical and chemical properties and the reactivity of the CCGP were investigated. Second, HD-RRM material was prepared, and its tensile performance characteristic parameters were investigated. Lastly, the hydration products and microstructure of HD-RRM were characterized through tests (e.g., non-evaporable water content, scanning electron microscopy (SEM), X-ray diffraction (XRD), and comprehensive thermogravimetric analysis and differential scanning calorimetry (TG-DSC)). As indicated by the experimental results, the CCGP with a particle size of 1250 mesh exhibited the maximum potential reactivity. The optimal mixing ratio for HD-RRM in the experiments comprised a water–cement ratio of 0.27, a sand–cement ratio of 0.3, a fiber volume fraction of 2%, a cement content of 70%, a CCGP content of 20%, a fly ash (FA) content of 10%, and a superplasticizer content of 0.1%. Using the abovementioned mix design, the prepared HD-RRM was endowed with a 6 h ultimate elongation of 2.75%, an ultimate tensile strength of 7.58 MPa, a compressive strength of 45.4 MPa, and an average crack width of 125.53 μm, which meets the requirements of repair materials and provides a design method for CCGP resource utilization and asphalt concrete road and bridge deck repair.
Predictive Modeling of Molecular Mechanisms in Hydrogen Production and Storage Materials
Authors: Banerjee Tanumoy , Balasubramanian Ganesh
Published: September 2023

Hydrogen has been widely considered to hold promise for solving challenges associated with the increasing demand for green energy. While many chemical and biochemical processes produce molecular hydrogen as byproducts, electrochemical approaches using water electrolysis are considered to be a predominant method for clean and green hydrogen production. We discuss the current state-of-the-art in molecular hydrogen production and storage and, more significantly, the increasing role of computational modeling in predictively designing and deriving insights for enhancing hydrogen storage efficiency in current and future materials of interest. One of the key takeaways of this review lies in the continued development and implementation of large-scale atomistic simulations to enable the use of designer electrolyzer–electrocatalysts operating under targeted thermophysical conditions for increasing green hydrogen production and improving hydrogen storage in advanced materials, with limited tradeoffs for storage efficiency.
Eco-Friendly Coal Gangue and/or Metakaolin-Based Lightweight Geopolymer with the Addition of Waste Glass
Authors: Ziejewska Celina , Bąk Agnieszka , Hodor Krzysztof , Hebda Marek
Published: September 2023

Massive amounts of deposited coal gangue derived from the mining industry constitute a crucial problem that must be solved. On the other hand, common knowledge about the recycling of glass products and the reuse of waste glass is still insufficient, which in turn causes economic and environmental problems. Therefore, this work investigated lightweight geopolymer foams manufactured based on coal gangue, metakaolin, and a mix of them to evaluate the influence of such waste on the geopolymer matrix. In addition, the effect of 20% (wt.) of waste glass on the foams was determined. Mineralogical and chemical composition, thermal behaviour, thermal conductivity, compressive strength, morphology, and density of foams were investigated. Furthermore, the structure of the geopolymers was examined in detail, including pore and structure thickness, homogeneity, degree of anisotropy, porosity with division for closed and open pores, as well as distribution of additives and pores using micro-computed tomography (microCT). The results show that the incorporation of waste glass increased compressive strength by approximately 54% and 9% in the case of coal-gangue-based and metakaolin-based samples, respectively. The porosity of samples ranged from 67.3% to 58.7%, in which closed pores constituted 0.3–1.8%. Samples had homogeneous distributions of pores and additions. Furthermore, the thermal conductivity ranged from 0.080 W/(m·K) to 0.117 W/(m·K), whereas the degree of anisotropy was 0.126–0.187, indicating that the structure of foams was approximate to isotropic.
Effect of Surface Treatments with Low-Pressure Plasma on the Adhesion of Zirconia
Authors: Sevilla Pablo , Gseibat Mustafa , Peláez Jesús , Suárez María J. , López-Suárez Carlos
Published: September 2023

The purpose of this study was to investigate the effect of low-pressure plasma on the contact angle, shear bond strength (SBS), and the failure mode of zirconia ceramic. Zirconia specimens were divided into three groups according to the surface treatment methods as follows: sandblasting with aluminum oxide (ZR-C), sandblasting with aluminum oxide and oxygen plasma (ZR-CP), and argon plasma (ZR-P). The contact angle, SBS, and surface characteristics were tested after thermocycling. Data analysis was made using the Kruskal–Wallis test and one-way analysis of variance. Plasma treatment significantly reduced the contact angle (p < 0.001) with the lowest value for the Zr-P group. An increase in oxygen and a decrease in carbon was observed on the zirconia surface in both plasma groups. For the SBS, there were significant differences among the groups (p < 0.018), the Zr-CP group showing the highest bond strength. Mixed failures were the most frequent. Plasma treatment was effective in increasing the wettability, increasing the oxygen/carbon ratio without changing zirconia surface morphology. The sandblasting plus plasma with oxygen group exhibited the highest bond strength.
Gray Model Study of Strength and Pore Structure of Recycled Concrete Powder (RCP) Concrete Based on Low-Field NMR Technology
Authors: Hou Yongli , Yu Zhengxing , Zhang Jianhua , Yang Hongrui , Song Weiqing
Published: September 2023

In order to improve the resource utilization of recycled concrete powder (RCP), this study aimed to investigate the effect of RCP admixture, curing age, and alkali excitation on the strength of RCP concrete. In addition, the pore structure characteristics of RCP concrete were analyzed in combination with low-field NMR. Furthermore, a gray predictive GM (1, 4) model was established to predict the mechanical properties of the concrete based on the pore structure parameters, especially the compressive and flexural tensile strengths. The results of the study indicate that the mechanical properties, namely compressive strength and flexural strength, of RCP concrete exhibit an initial increase followed by a subsequent decrease with increasing RCP content at 3 d, 7 d, and 28 d curing ages. In particular, the concrete exhibits the highest mechanical properties when the RCP content reaches 10%. As the curing age increases, the RCP gradually achieves full hydration, resulting in further refinement of the concrete pores and a denser structure, which subsequently improves the mechanical properties. In addition, the strength growth rate of alkali-excited recycled concrete (ARC) showed a continuous increase, indicating that alkali excitation increasingly improved the mechanical properties of the concrete. Furthermore, the study accurately predicted the mechanical properties of RCP concrete by using GM (1, 4) prediction models for its compressive strength and flexural tensile strength using pore characteristic parameters.
Synthesis and Characterization of a Novel Two-Dimensional Copper p-Aminophenol Metal–Organic Framework and Investigation of Its Tribological Properties
Authors: Li Lei , Liu Zhijun , Li Chuan , Wang Xiaodong , Li Mingling
Published: September 2023

Here, a novel copper p-aminophenol metal–organic framework (Cu(PAP)2) is first reported. Powder X-ray diffraction (PXRD), infrared spectra (FTIR), Raman spectra, transmission electron microscopy (TEM) and X-ray photoemission spectroscopy (XPS), in combination with a structure simulation, indicated that Cu(PAP)2 is a two-dimensional (2D) material with a staggered structure analogous to that of graphite. Based on its 2D graphite-like layer structure, Cu(PAP)2 was expected to exhibit preferable tribological behaviors as an additive in liquid lubricants, and the tribological properties of Cu(PAP)2 as a lubricating additive in hydrogenated polydecene (PAO6) or deionized water were investigated. Compared to PAO6 or deionized water, the results indicated that deionized water-based Cu(PAP)2 showed much better friction reduction and anti-wear behavior than PAO6-based Cu(PAP)2 did, which was due to Cu(PAP)2 penetrating the interface between friction pairs in deionized water, but not in PAO6, thus producing lower friction and wear resistance values.
Numerical Method for Fractional-Order Generalization of the Stochastic Stokes–Darcy Model
Authors: Berdyshev Abdumauvlen , Baigereyev Dossan , Boranbek Kulzhamila
Published: September 2023

This paper is aimed at efficient numerical implementation of the fractional-order generalization of the stochastic Stokes–Darcy model, which has important scientific, applied, and economic significance in hydrology, the oil industry, and biomedicine. The essence of this generalization of the stochastic model is the introduction of fractional time derivatives in the sense of Caputo’s definition to take into account long-term changes in the properties of media. An efficient numerical method for the implementation of the fractional-order Stokes–Darcy model is proposed, which is based on the use of a higher-order approximation formula for the fractional derivative, higher-order finite difference relations, and a finite element approximation of the problem in the spatial direction. In the paper, a rigorous theoretical analysis of the stability and convergence of the proposed numerical method is carried out, which is confirmed by numerous computational experiments. Further, the proposed method is applied to the implementation of the fractional-order stochastic Stokes–Darcy model using an ensemble technique, in which the approximation is carried out in such a way that the resulting systems of linear equations have the same coefficient matrix for all realizations. Furthermore, evaluation of the discrete fractional derivatives is carried out with the use of parallel threads. The efficiency of applying both approaches has been demonstrated in numerical tests.
Prabhakar Functions of Le Roy Type: Inequalities and Asymptotic Formulae
Authors: Paneva-Konovska Jordanka
Published: September 2023

In this paper, the four-index generalization of the classical Le Roy function is considered on a wider set of parameters and its order and type are given. Letting one of the parameters take non-negative integer values, a family of functions with such a type of index is constructed. The behaviour of these functions is studied in the complex plane C and in different domains thereof. First, several inequalities are obtained in C, and then they are modified on its compact subsets as well. Moreover, an asymptotic formula is proved for ‘large’ values of the indices of these functions. Additionally, the multi-index analogue of the abovementioned four-index Le Roy type function is considered and its basic properties are obtained. Finally, several special cases of the two functions under consideration are discussed.
A Hybrid MCDM Approach Based on Fuzzy MEREC-G and Fuzzy RATMI
Authors: Makki Anas A. , Abdulaal Reda M. S.
Published: September 2023

Multi-criteria decision-making (MCDM) assists in making judgments on complex problems by evaluating several alternatives based on conflicting criteria. Several MCDM methods have been introduced. However, real-world problems often involve uncertain and ambiguous decision-maker inputs. Therefore, fuzzy MCDM methods have emerged to handle this problem using fuzzy logic. Most recently, the method based on the removal effects of criteria using the geometric mean (MEREC-G) and ranking the alternatives based on the trace to median index (RATMI) were introduced. However, to date, there is no fuzzy extension of the two novel methods. This study introduces a new hybrid fuzzy MCDM approach combining fuzzy MEREC-G and fuzzy RATMI. The fuzzy MEREC-G can accept linguistic input terms from multiple decision-makers and generates consistent fuzzy weights. The fuzzy RATMI can rank alternatives according to their fuzzy performance scores on each criterion. The study provides the algorithms of both fuzzy MEREC-G and fuzzy RATMI and demonstrates their application in adopted real-world problems. Correlation and scenario analyses were performed to check the new approach’s validity and sensitivity. The new approach demonstrates high accuracy and consistency and is sufficiently sensitive to changes in the criteria weights, yet not too sensitive to produce inconsistent rankings.
A Richness Estimator Based on Integrated Data
Authors: Chiu Chun-Huo
Published: September 2023

Species richness is a widely used measure for assessing the diversity of a particular area. However, observed richness often underestimates the true richness due to resource limitations, particularly in a small-sized sample or highly heterogeneous assemblage. To estimate the number of different species (species richness) present across several different sites (communities), researchers often use a combined collection of data (an integrated dataset). This dataset is created by collecting samples from each site individually and independently. However, the pooled sample of integrated data is no longer a random sample from the entire area, and the use of different sampling schemes results in different collected data formats. Consequently, employing a single sampling distribution to model the pooled sample becomes unfeasible, rendering existing richness estimators inadequate. This study provides a theoretical explanation for the applicability of Chao’s lower bound estimator in assessing species richness across multiple sites based on the pooled sample. Additionally, a new non-parametric estimator is introduced, which adjusts the bias of Chao’s lower bound estimator by leveraging the Good–Turing frequency formula. This proposed estimator only utilizes the richness of singletons, doubletons, and tripletons in the pooled sample to estimate undetected richness. Simulated datasets across various models are employed to demonstrate the statistical performance of the estimator, showcasing its ability to reduce the bias of observed richness and provide accurate 95% confidence intervals. Real datasets are also utilized to illustrate the practical application of the proposed approach.
The Hybrid Modeling of Spatial Autoregressive Exogenous Using Casetti’s Model Approach for the Prediction of Rainfall
Authors: Falah Annisa Nur , Ruchjana Budi Nurani , Abdullah Atje Setiawan , Rejito Juli
Published: September 2023

Spatial Autoregressive (SAR) models are used to model the relationship between variables within a specific region or location, considering the influence of neighboring variables, and have received considerable attention in recent years. However, when the impact of exogenous variables becomes notably pronounced, an alternative approach is warranted. Spatial Expansion, coupled with the Casetti model approach, serves as an extension of the SAR model, accommodating the influence of these exogenous variables. This modeling technique finds application in the realm of rainfall prediction, where exogenous factors, such as air temperature, humidity, solar irradiation, wind speed, and surface pressure, play pivotal roles. Consequently, this research aimed to combine the SAR and Spatial Expansion models through the Casetti model approach, leading to the creation of the Spatial Autoregressive Exogenous (SAR-X) model. The SAR-X was employed to forecast the rainfall patterns in the West Java region, utilizing data obtained from the National Aeronautics and Space Administration Prediction of Worldwide Energy Resources (NASA POWER) dataset. The practical execution of this research capitalized on the computational capabilities of the RStudio software version 2022.12.0. Within the framework of this investigation, a comprehensive and integrated RStudio script, seamlessly incorporated into the RShiny web application, was developed so that it is easy to use.
Fourth-Order Difference Scheme and a Matrix Transform Approach for Solving Fractional PDEs
Authors: Salman Zahrah , Tavassoli Kajani Majid , Mechee Mohammed , Allame Masoud
Published: September 2023

Proposing a matrix transform method to solve a fractional partial differential equation is the main aim of this paper. The main model can be transferred to a partial-integro differential equation (PIDE) with a weakly singular kernel. The spatial direction is approximated by a fourth-order difference scheme. Also, the temporal derivative is discretized via a second-order numerical procedure. First, the spatial derivatives are approximated by a fourth-order operator to compute the second-order derivatives. This process produces a system of differential equations related to the time variable. Then, the Crank–Nicolson idea is utilized to achieve a full-discrete scheme. The kernel of the integral term is discretized by using the Lagrange polynomials to overcome its singularity. Subsequently, we prove the convergence and stability of the new difference scheme by utilizing the Rayleigh–Ritz theorem. Finally, some numerical examples in one-dimensional and two-dimensional cases are presented to verify the theoretical results.
Keller–Osserman Phenomena for Kardar–Parisi–Zhang-Type Inequalities
Authors: Muravnik Andrey B.
Published: September 2023

For coercive quasilinear partial differential inequalities containing nonlinearities of the Kardar–Parisi–Zhang type, we find conditions guaranteeing the absence of global positive solutions. These conditions extend both the classical result of Keller and Osserman and its recent Kon’kov–Shishkov generalization. Additionally, they complement the results for the noncoercive case, which had been previously established by the same author.
Dignity as a Central Issue in Treating Patients with Dementia Associated with COVID-19 Infection
Authors: Hostiuc Sorin , Drima Eduard
Published: September 2023

COVID-19 was initially considered a primary respiratory disorder associated with various short- and long-term complications, affecting many patients and imposing a significant burden. Patients who have dementia are especially vulnerable to the SARS-CoV2 infection, which is associated with an increased risk for neuropsychiatric complications. These patients need a unique approach to managing ethical issues related to the COVID-19 pandemic, including autonomy, veracity, non-maleficence, justice, compassion, and dignity. The latter is one of the most elusive and misunderstood concepts in medical ethics and is extremely important in debates surrounding the proper management of patients with dementia. However, it is often left out of ethical analysis, as most clinicians, when debating issues associated with clinical practice, often evaluate only the “classical” principles of biomedical ethics. In this article, we aim to assess the unique features of dignity in treating this group of patients during the COVID-19 pandemic. We will briefly analyze dignity as a bioethical concept. We will further explore its principal axes, namely compassion, creating a humane and purposeful environment, employing persuasion to meet the person’s essential needs, exerting a certain degree of mild restraint to meet the person’s critical needs, minimizing harm in terminal care, and justice, through the lens of people who had dementia during the COVID-19 pandemic. Applying this principle in clinical practice requires significant commitment from all healthcare workers. New approaches to the analysis of dignity, such as through the Ring Theory of Personhood, may facilitate its understanding by practitioners and aid its implementation in populations with multiple vulnerabilities, such as dementia patients, during an infectious outbreak that generates significant social and medical changes.
The Attitude of Egyptian Patients with Autoimmune and Rheumatic Diseases towards Telemedicine
Authors: Tharwat Samar , Gamal Doaa
Published: September 2023

Background and Objectives: The use of telemedicine (TM) has recently undergone rapid growth and proliferation. Professional stakeholders anticipate that TM will aid in the efficient allocation of limited resources in rheumatology care. The aim of the study was to evaluate the acceptance and willingness of Egyptian patients with autoimmune and rheumatic diseases (ARDs) to incorporate TM into rheumatological care and to assess their requirements and concerns regarding TM. Materials and Methods: A cross-sectional questionnaire-based study was conducted among Egyptian patients with ARDs. The questionnaire covered sociodemographic characteristics, clinical and therapeutic data, attitudes, barriers, and motivators towards TM. Results: The study included 189 patients with ARDs, with a mean age of 37 years (SD  =  11.71), and 88.4% were females. Participants were divided into two groups based on their acceptance of TM: the non-acceptant group (133, 70.4%) and the acceptant group (56, 29.6%). There was a significant difference in educational level (p = 0.001), chronic kidney and heart disease (p = 0.008 and 0.014, respectively) and hydroxychloroquine administration (p = 0.037) between the two groups. During the coronavirus disease 2019 (COVID-19) pandemic, 96 (50.8%) of participants used virtual rheumatology consultations, mainly using WhatsApp (64.6%). Approximately 87% would require assistance in operating TM technology. The preference for direct conversation with the rheumatologist and the need for physical examination were the main barriers to teleconsultation. Conclusions: TM is opposed by the vast majority of Egyptian patients with ARDs. They are concerned since it does not include a physical examination and prevents them from undergoing additional procedures such as ultrasound and blood testing. The majority of Egyptian patients with ARDs need help using TM technology, which is the most significant barrier to the spread of TM.
Preptin: A New Bone Metabolic Parameter?
Authors: Ungureanu Maria-Christina , Bilha Stefana Catalina , Hogas Mihai , Velicescu Cristian , Leustean Letitia , Teodoriu Laura Claudia , Preda Cristina
Published: September 2023

Preptin is a 34-aminoacid peptide derived from the E-peptide of pro-insulin-like growth factor 2 (pro-IGF2) that is co-secreted with insulin and upregulates glucose-mediated insulin secretion. High serum preptin levels were described in conditions associated with insulin resistance, such as polycystic ovary syndrome and type 2 diabetes mellitus (T2M). Insulin and also IGF2 are known to be anabolic bone hormones. The “sweet bone” in T2M usually associates increased density, but altered microarchitecture. Therefore, preptin was proposed to be one of the energy regulatory hormones that positively impacts bone health. Experimental data demonstrate a beneficial impact of preptin upon the osteoblasts. Preptin also appears to regulate osteocalcin secretion, which in turn regulates insulin sensitivity. Preptin is greatly influenced by the glucose tolerance status and the level of physical exercise, both influencing the bone mass. Clinical studies describe low serum preptin concentrations in osteoporosis in both men and women, therefore opening the way towards considering preptin a potential bone anabolic therapy. The current review addresses the relationship between preptin and bone mass and metabolism in the experimental and clinical setting, also considering the effects of preptin on carbohydrate metabolism and the pancreatic–bone loop.
Fabrication of µFFE Devices in COC via Hot Embossing with a 3D-Printed Master Mold
Authors: LeMon Matthew B. , Douma Cecilia C. , Burke Gretchen S. , Bowser Michael T.
Published: September 2023

The fabrication of high-performance microscale devices in substrates with optimal material properties while keeping costs low and maintaining the flexibility to rapidly prototype new designs remains an ongoing challenge in the microfluidics field. To this end, we have fabricated a micro free-flow electrophoresis (µFFE) device in cyclic olefin copolymer (COC) via hot embossing using a PolyJet 3D-printed master mold. A room-temperature cyclohexane vapor bath was used to clarify the device and facilitate solvent-assisted thermal bonding to fully enclose the channels. Device profiling showed 55 µm deep channels with no detectable feature degradation due to solvent exposure. Baseline separation of fluorescein, rhodamine 110, and rhodamine 123, was achieved at 150 V. Limits of detection for these fluorophores were 2 nM, 1 nM, and 10 nM, respectively, and were comparable to previously reported values for glass and 3D-printed devices. Using PolyJet 3D printing in conjunction with hot embossing, the full design cycle, from initial design to production of fully functional COC µFFE devices, could be completed in as little as 6 days without the need for specialized clean room facilities. Replicate COC µFFE devices could be produced from an existing embossing mold in as little as two hours.
Increasing Heat Transfer from Metal Surfaces through Laser-Interference-Induced Microscopic Heat Sinks
Authors: Schell Frederic , Chukwudi Okafor Richard , Steege Tobias , Alamri Sabri , Ghevariya Savan , Zwahr Christoph , Lasagni Andrés F.
Published: September 2023

With the increasing processing power of micro-electronic components and increasing spatial limitations, ensuring sufficient heat dissipation has become a crucial task. This work presents a microscopic approach to increasing the surface area through periodic surface structures. Microstructures with a periodic distance of 8.5 µm are fabricated via Direct Laser Interference Patterning (DLIP) on stainless steel plates with a nanosecond-pulsed infrared laser and are characterized by their developed interfacial area ratio. The optimal structuring parameters for increasing the surface area were investigated, reaching peak-to-valley depths up to 12.8 µm and increasing surface area by up to 394%. Heat dissipation in a natural convection environment was estimated by measuring the output voltage of a Peltier element mounted between a hot plate and a textured sample. The resulting increase in output voltage compared to an unstructured sample was correlated to the structure depth and developed interfacial area ratio, finding a maximum increase of 51.4%. Moreover, it was shown that the output voltage correlated well with the structure depth and surface area.
Developing an Amide-Spacered Triterpenoid Rhodamine Hybrid of Nano-Molar Cytotoxicity Combined with Excellent Tumor Cell/Non-Tumor Cell Selectivity
Authors: Heise Niels V. , Denner Toni C. , Becker Selina , Hoenke Sophie , Csuk René
Published: September 2023

Asiatic acid, a pentacyclic triterpene, was converted into a series of piperazinyl, homopiperazinyl, and 1,5-diazocinyl spacered rhodamine conjugates, differing in the type of spacer and the substitution pattern on the rhodamine moiety of the hybrids. The compounds were tested for cytotoxic activity in SRB assays and compound 12, holding an EC50 of 0.8 nM, was the most cytotoxic compound of this series, but compound 18 (containing a ring expanded 1,5-diazocinyl moiety and n-propyl substituents on the rhodamine) was the most selective compound exhibiting a selectivity factor of almost 190 while retaining high cytotoxicity (EC50 = 1.9 nM, for A2780 ovarian carcinoma).
The Synergistic Effect in CdS/g-C3N4 Nanoheterojunctions Improves Visible Light Photocatalytic Performance for Hydrogen Evolution Reactions
Authors: Niu Yu , Shen Jinni , Guo Wenqin , Zhu Xiaoyan , Guo Lanlan , Wang Yueqi , Li Fuying
Published: September 2023

This study focuses on the development of heterojunction photocatalysts for the efficient utilization of solar energy to address the energy crisis and reduce environmental pollution. Cadmium sulfide (CdS)/graphite-type carbon nitride (g-C3N4) nanocomposites were synthesized using a hydrothermal method, and their photoelectrochemical properties and photocatalytic performance for hydrogen evolution reaction (HER) were characterized. Scanning electron microscope images showed the intimate interface and caviar-like nanoheterojunction of the CdS nanoparticles on g-C3N4 nanospheres, suggesting their potential involvement in the photocatalytic process. Electrochemical and spectroscopic analyses were conducted to confirm the roles of CdS in the nanoheterojunction. The results showed that 10 wt% CdS/g-C3N4 nanospheres exhibited higher photocatalytic activity than pure g-C3N4 under visible light irradiation. A HER rate of 655.5 μmol/g/h was achieved after three photocatalytic cycles, signifying good photocatalytic stability. The synergistic effect of the Z-scheme heterojunction formed by g-C3N4 and CdS was identified as the main factor responsible for the enhanced photocatalytic performance and stability. The interface engineering effect of CdS/g-C3N4 facilitated the separation of photogenerated electrons and holes. This study provides insights into the design and fabrication of efficient HER photocatalysts.
Highly Substituted 10-RO-(hetero)acenes—Electric Properties of Vacuum-Deposited Molecular Films
Authors: Marciniak Bernard , Kania Sylwester , Bałczewski Piotr , Różycka-Sokołowska Ewa , Wilk Joanna , Koprowski Marek , Stańdo Jacek , Kuliński Janusz
Published: September 2023

The functionalization of the aromatic backbone allows the improvement of the electrical properties of acene molecules in the amorphous layered structures of organic thin films. In the present work, we discuss the electric properties of the stable, amorphous, vacuum-deposited films prepared from five highly substituted 10-RO-acenes of various electronic properties, i.e., two extreme electron-donor (1,3-dioxa-cyclopenta[b]) anthracenes with all RO substituents, two anthracene carbaldehydes and one benzo[b]carbazole carbaldehyde possessing both electron-donor and acceptor substituents. The hole mobility data were obtained using subsequent steady state space charge limited currents (SCLC) and Time of Flight (TOF) measurements, performed on the same sample and these were then compared with the results of theoretical hole mobility calculations obtained using the Density Functional Theory (DFT) quantum—chemical calculations using the Marcus–Hush theory. The study shows a good agreement between the theoretical and experimental values which allows for the quick and quantitative estimation of Einstein’s mobility values for highly substituted 10-RO anthracene and benzo[b]carbazole based on chemical calculations. This agreement also proves that the transport of holes follows the hopping mechanism. The theoretical calculations indicate that the reorganization energy plays a decisive role in the transport of holes in the amorphous layers of highly substituted hetero(acenes).
Green Synthesis of Silver Nanoparticles Derived from Papaver rhoeas L. Leaf Extract: Cytotoxic and Antimicrobial Properties
Authors: İpek Polat , Yıldız Reşit , Baran Mehmet Fırat , Hatipoğlu Abdulkerim , Baran Ayşe , Sufianov Albert , Beylerli Ozal
Published: September 2023

In the last few decades, the search for metal nanoparticles as an alternative to cancer treatments and antibiotics has increased. In this article, the spectroscopic (ultraviolet–visible (UV-vis), electron-dispersing X-ray (EDX), and Fourier transform infrared (FT-IR)), microscopic (field emission scanning electron microscope (FE-SEM), transmission electron microscope (TEM), and atomic force microscope (AFM)), structural (X-ray diffractometer (XRD) and zetasizer), and analytic (thermogravimetric/differential thermal analyzer (TGA-DTA)) characterization of the silver nanoparticles (AgNPs) produced from Papaver rhoeas (PR) L. leaf extract are presented. PR-AgNPs are generally spherical and have a maximum surface plasmon resonance of 464.03 nm. The dimensions of the manufactured nanomaterial are in the range of 1.47–7.31 nm. PR-AgNPs have high thermal stability and a zeta potential of −36.1 mV. The minimum inhibitory concentration (MIC) values (mg L−1) of PR-AgNPs on Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa, and Candida albicans are 1.50, 0.75, 3.00, 6.00, and 0.37, respectively. In the study, the cytotoxic and proliferative effects of PR-AgNPs using the MTT (3-(4,5-dimethylthiazol-2-yl)-diphenyltetrazolium bromide) method on various cancer cell lines (CACO-2 (human colon adenocarcinoma cell), MCF-7 (human breast cancer cell), T98-G (glioblastoma multiforme cell), and healthy HUVEC (human umbilical vein endothelial cell)) cell lines are presented. After 24 and 48 h of the application, the half-maximum inhibitory concentration (IC50) values (μg mL−1) of PR-AgNPs on HUVEC, CACO-2, MCF-7, and T98-G lines are 2.365 and 2.380; 2.526 and 2.521; 3.274 and 3.318; 3.472 and 3.526, respectively. Comprehensive in vivo research of PR-AgNPs is proposed to reveal their potential for usage in sectors such as nanomedicine and nanochemistry.
Six New Phenolic Glycosides from the Seeds of Moringa oleifera Lam. and Their α-Glucosidase Inhibitory Activity
Authors: Li Lin-Zhen , Chen Liang , Tu Yang-Li , Dai Xiang-Jie , Xiao Sheng-Jia , Shi Jing-Shan , Li Yong-Jun , Yang Xiao-Sheng
Published: September 2023

Plant-derived phytochemicals have recently drawn interest in the prevention and treatment of diabetes mellitus (DM). The seeds of Moringa oleifera Lam. are widely used in food and herbal medicine for their health-promoting properties against various diseases, including DM, but many of their effective constituents are still unknown. In this study, 6 new phenolic glycosides, moringaside B–G (1–6), together with 10 known phenolic glycosides (7–16) were isolated from M. oleifera seeds. The structures were elucidated by 1D and 2D NMR spectroscopy and high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) data analysis. The absolute configurations of compounds 2 and 3 were determined by electronic circular dichroism (ECD) calculations. Compounds 2 and 3 especially are combined with a 1,3-dioxocyclopentane moiety at the rhamnose group, which are rarely reported in phenolic glycoside backbones. A biosynthetic pathway of 2 and 3 was assumed. Moreover, all the isolated compounds were evaluated for their inhibitory activities against α-glucosidase. Compounds 4 and 16 exhibited marked activities with IC50 values of 382.8 ± 1.42 and 301.4 ± 6.22 μM, and the acarbose was the positive control with an IC50 value of 324.1 ± 4.99 μM. Compound 16 revealed better activity than acarbose.
Synthesis and In Vitro Anticancer Activity of Novel 4-Aryl-3-(4-methoxyphenyl)-1-phenyl-1H-pyrazolo[3,4-b]pyridines Arrest Cell Cycle and Induce Cell Apoptosis by Inhibiting CDK2 and/or CDK9
Authors: Almansour Basma S. , Binjubair Faizah A. , Abdel-Aziz Alaa A.-M. , Al-Rashood Sara T.
Published: September 2023

Two series of pyrazolo[3,4-b]pyridine derivatives, 9a–h and 14a–h, are synthesized and evaluated for their anti-cancer potency towards Hela, MCF7, and HCT-116 cancer cell lines. Compound 9a showed the highest anticancer activity with IC50 = 2.59 µM against Hela when compared with doxorubicin (IC50 = 2.35 µM). Compound 14g revealed cytotoxicity IC50 = 4.66 and 1.98 µM towards MCF7 and HCT-116 compared to doxorubicin with IC50 = 4.57 and 2.11 µM, respectively. Compound 9a exhibited cell cycle arrest at the S phase for Hela, whereas 14g revealed an arresting cell cycle for MCF7 at G2/M phase and an arresting cell cycle at S phase in HCT-116. In addition, 9a induced a significant level of early and late apoptosis in Hela when compared with the control cells, whereas 14g induced an apoptosis in MCF7 and HCT-116, respectively. Compounds 9a (IC50 = 26.44 ± 3.23 µM) and 14g (IC50 = 21.81 ± 2.96 µM) showed good safety profiles on normal cell line WI-38. Compounds 9a and 14g showed good inhibition activity towards CDK2, with IC50 = 1.630 ± 0.009 and 0.460 ± 0.024 µM, respectively, when compared with ribociclib (IC50 = 0.068 ± 0.004). Furthermore, 9a and 14g showed inhibitory activity towards CDK9 with IC50 = 0.262 ± 0.013 and 0.801 ± 0.041 µM, respectively, related to IC50 of ribociclib = 0.050 ± 0.003. Docking study for 9a and 14g exhibited good fitting in the CDK2 and CDK9 active sites.
The Use of Crystal Violet Degradation Products for Ballpoint Pen Ink Manuscript Dating
Authors: Díaz-Santana Óscar , Cárdenes-Sánchez Nuria , Conde-Hardisson Francisco , Rivero-Rosales Argimiro , Suárez de Tangil Navarro Miguel , Vega-Moreno Daura
Published: September 2023

Determining the approximate dates that written documents were drawn up based on the chemical composition of the ink is not a simple process. It is very demanding in terms of legal requirements. Various studies have succeeded in dating manuscripts by analyzing the temporal evolutions of the concentrations of dyes and solvents in documents based on the original formulations of the ink pens. These analyses were carried out simultaneously by HPLC-DAD for dyes and by GC-MS for solvents. This study aims, for the first time, to evaluate novel ink compounds and the temporal evolution of the concentrations of the degradation products of the dyes used by most suppliers and which are present in almost all types of ballpoint inks, i.e., Crystal Violet (CV). CV degrades through two parallel pathways: on the one hand, it undergoes progressive demethylation until it becomes pararosaniline, and on the other, it undergoes a breakdown of the molecule obtaining, among other by-products, the compound N,N′-Dimethyl-4-aminophenol (NNAPH), that was experimentally verified using four different inks (e.g., Inoxcrom® and Sigma® brands, in blue and black). For the NNAPH compound, we observed that four of the inks under analysis displayed the same temporary behavior despite having different initial chemical compositions. These initial results show the high potential for both CV and NNAPH, together with the rest of the pararosaniline family, as age tracers for dated/old documents. These techniques may potentially open up new avenues for universal dating tools, regardless of the brands of ink employed for use in different ballpoint pen types.
Electrode Materials, Structural Design, and Storage Mechanisms in Hybrid Supercapacitors
Authors: Du Xiaobing , Lin Zhuanglong , Wang Xiaoxia , Zhang Kaiyou , Hu Hao , Dai Shuge
Published: September 2023

Currently, energy storage systems are of great importance in daily life due to our dependence on portable electronic devices and hybrid electric vehicles. Among these energy storage systems, hybrid supercapacitor devices, constructed from a battery-type positive electrode and a capacitor-type negative electrode, have attracted widespread interest due to their potential applications. In general, they have a high energy density, a long cycling life, high safety, and environmental friendliness. This review first addresses the recent developments in state-of-the-art electrode materials, the structural design of electrodes, and the optimization of electrode performance. Then we summarize the possible classification of hybrid supercapacitor devices, and their potential applications. Finally, the fundamental theoretical aspects, charge-storage mechanism, and future developing trends are discussed. This review is intended to provide future research directions for the next generation of high-performance energy storage devices.
Interactions between Polygenetic Variants and Lifestyle Factors in Hypothyroidism: A Hospital-Based Cohort Study
Authors: Kim Da Sol , Park Sunmin
Published: September 2023

Hypothyroidism is a prevalent endocrine disorder and is associated with a variety of metabolic disturbances. This study aimed to investigate the polygenic variants associated with hypothyroidism risk and the interaction of polygenic risk scores (PRS) with dietary patterns in influencing disease risk in 56,664 participants aged >40 in a hospital-based cohort. The participants were classified as having hypothyroidism (n = 870) diagnosed by a physician and no hypothyroidism (n = 55,794). Genetic variants associated with hypothyroidism were identified using a genome-wide association study (GWAS). Genetic variants interacting with each other were selected using a generalized multifactor dimensionality reduction analysis, and the PRS generated was evaluated for interaction with lifestyle parameters. Coffee, alcohol, meat intake, and a Korean balanced diet were inversely associated with hypothyroidism risk, as were selenium, copper, and manganese intakes. White blood cell (WBC) counts and serum alkaline phosphatase and triglyceride concentrations were positively associated with hypothyroidism risk, as were osteoporosis and thyroid cancer. The GMDR analysis generated a three-single nucleotide polymorphism (SNP) model comprising dual oxidase-1 (DUOX1)_rs1648314; thyroid-stimulating hormone receptor (TSHR)_rs75664963; and major histocompatibility complex, class-II, DQ Alpha-1 (HLA-DQA1)_rs17426593. The PRS derived from the three- and seven-SNP models were associated with a 2.11- and 2.32-fold increase in hypothyroidism risk, respectively. Furthermore, the PRS from the three-SNP model showed interactions with WBC counts, wherein the positive association with hypothyroidism risk was more pronounced in participants with low WBC counts than those with high WBC counts (≥4 × 109 /L). Dietary patterns, such as the plant-based diet (PBD) and the Western-style diet (WSD), along with smoking status, exhibited interactions with the PRS, influencing hypothyroidism risk. In participants with a high PRS, those in the high-PBD, low-WSD, and smoker groups had a higher proportion of hypothyroidism than those in the low-PBD, high-WSD, and non-smoker groups. In conclusion, genetic variants related to immunity and thyroid hormone secretion were linked to hypothyroidism risk, and their PRS interacted with PBD and WSD intake and smoking status. These results contribute to a better understanding of hypothyroidism and its prevention strategies for precision medicine intervention.