bluuebunny/crossref_metadata_2025 huggingface dataset:
Remarks on Sequential Caputo Fractional Differential Equations with Fractional Initial and Boundary Conditions
Authors: Vatsala Aghalaya S. , Sambandham Bhuvaneswari
Published: December 2024

In the literature so far, for Caputo fractional boundary value problems of order 2q when 1<2q<2, the problems use the same boundary conditions of the integer-order differential equation of order ‘2’. In addition, they only use the left Caputo derivative in computing the solution of the Caputo boundary value problem of order 2q. Further, even the initial conditions for a Caputo fractional differential equation of order nq use the corresponding integer-order initial conditions of order ‘n’. In this work, we establish that it is more appropriate to use the Caputo fractional initial conditions and Caputo fractional boundary conditions for sequential initial value problems and sequential boundary value problems, respectively. It is to be noted that the solution of a Caputo fractional initial value problem or Caputo fractional boundary value problem of order ‘nq’ will only be a Cnq solution and not a Cn solution on its interval. In this work, we present a methodology to compute the solutions of linear sequential Caputo fractional differential equations using initial and boundary conditions of fractional order kq, k=0,1,…(n−1) when the order of the fractional derivative involved in the differential equation is nq. The Caputo left derivative can be computed only when the function can be expressed as f(x−a). Then the Caputo right derivative of the same function will be computed for the function f(b−x). Further, we establish that the relation between the Caputo left derivative and the Caputo right derivative is very essential for the study of Caputo fractional boundary value problems. We present a few numerical examples to justify that the Caputo left derivative and the Caputo right derivative are equal at any point on the Caputo function’s interval. The solution of the linear sequential Caputo fractional initial value problems and linear sequential Caputo fractional boundary value problems with fractional initial conditions and fractional boundary conditions reduces to the corresponding integer initial and boundary value problems, respectively, when q=1. Thus, we can use the value of q as a parameter to enhance the mathematical model with realistic data.
Efficient Finite-Difference Estimation of Second-Order Parametric Sensitivities for Stochastic Discrete Biochemical Systems
Authors: Jabeen Fauzia , Ilie Silvana
Published: December 2024

Biochemical reaction systems in a cell exhibit stochastic behaviour, owing to the unpredictable nature of the molecular interactions. The fluctuations at the molecular level may lead to a different behaviour than that predicted by the deterministic model of the reaction rate equations, when some reacting species have low population numbers. As a result, stochastic models are vital to accurately describe system dynamics. Sensitivity analysis is an important method for studying the influence of the variations in various parameters on the output of a biochemical model. We propose a finite-difference strategy for approximating second-order parametric sensitivities for stochastic discrete models of biochemically reacting systems. This strategy utilizes adaptive tau-leaping schemes and coupling of the perturbed and nominal processes for an efficient sensitivity estimation. The advantages of the new technique are demonstrated through its application to several biochemical system models with practical significance.
Optimization of Collagen Extraction from Fish Scales Using Tris-Glycine Buffer: A Taguchi Methodological Approach
Authors: Makgobole Mokgadi Ursula , Onwubu Stanley Chibuzor , Baruwa Abayomi , Mpofana Nomakhosi , Obiechefu Zodidi , Naidoo Deneshree , Khathi Andile , Mkhwanazi Blessing
Published: December 2024

Collagen, a critical biomaterial with wide applications in pharmaceuticals, cosmetics, and medical industries, can be sourced sustainably from fish scales. This study optimizes the extraction of collagen using Tris-Glycine buffer from fish scales via the Taguchi method. Various extraction parameters—buffer concentration, temperature, pH, and time—were evaluated to identify optimal conditions. Under optimal conditions (0.5 M of acetic acids, volume of acids of 100 mL, soaking time of 120 min, and Tris-Glycine buffer of 10 mL), the results demonstrate that temperature and buffer concentration significantly influence collagen yield, with a collagen purity of 17.14 ± 0.05 mg/g. R2 value of 73.84% was obtained for the mathematical model). FTIR analysis confirmed the presence of characteristic collagen peaks at 1611 cm−1 (amide I), 1523 cm−1 (amide II), and 1300 cm−1 (amide III), indicating the successful extraction of type I collagen. SDS-PAGE analysis revealed a protein banding pattern consistent with the molecular weight of collagen, and amino acid analysis shows high percentages of glycine (20.98%), proline (15.43%), and hydroxyproline (11.51%), implying fibrous collagen structures. The finding suggests that the Taguchi method offers an efficient and sustainable approach for collagen extraction, reducing waste from fish processing industries. Nevertheless, there is a need for further experimental validation to align with mathematical modeling on the optimized conditions.
Butyrolactone-I from Marine Fungal Metabolites Mitigates Heat-Stress-Induced Apoptosis in IPEC-J2 Cells and Mice Through the ROS/PERK/CHOP Signaling Pathway
Authors: Niu Xueting , Chen Shengwei , Wang Xinchen , Wen Jiaying , Liu Xiaoxi , Yong Yanhong , Yu Zhichao , Ma Xingbing , Abd El-Aty A. M. , Ju Xianghong
Published: December 2024

Heat stress poses a significant challenge to animal husbandry, contributing to oxidative stress, intestinal mucosal injury, and apoptosis, which severely impact animal health, growth, and production efficiency. The development of safe, sustainable, and naturally derived solutions to mitigate these effects is critical for advancing sustainable agricultural practices. Butyrolactone-I (BTL-I), a bioactive compound derived from deep-sea fungi (Aspergillus), shows promise as a functional feed additive to combat heat stress in animals. This study explored the protective effects of BTL-I against heat-stress-induced oxidative stress and apoptosis in IPEC-J2 cells and mice. Our findings demonstrated that BTL-I effectively inhibited the heat-stress-induced upregulation of HSP70 and HSP90, alleviating intestinal heat stress. Both in vitro and in vivo experiments revealed that heat stress increased intestinal cell apoptosis, with a significant upregulation of Bax/Bcl-2 expression, while BTL-I pretreatment significantly reduced apoptosis-related protein levels, showcasing its protective effects. Furthermore, BTL-I suppressed oxidative stress markers (ROS and MDA) while enhancing antioxidant activity (SOD levels). BTL-I also reduced the expression of p-PERK, p-eIF2α, ATF4, and CHOP, mitigating oxidative and endoplasmic reticulum stress in intestinal cells. In conclusion, BTL-I demonstrates the potential to improve animal resilience to heat stress, supporting sustainable livestock production systems. Its application as a natural, eco-friendly feed additive will contribute to the development of sustainable agricultural practices.
Exploring Cognitive Deficits and Neuromodulation in Schizophrenia: A Narrative Review
Authors: Hung Chien-Chen , Lin Ko-Huan , Chang Hsin-An
Published: December 2024

Cognitive deficits are emerging as critical targets for managing schizophrenia and enhancing clinical and functional outcomes. These deficits are pervasive among individuals with schizophrenia, affecting various cognitive domains. Traditional pharmacotherapy and cognitive behavioral therapy (CBT) have limitations in effectively addressing cognitive impairments in this population. Neuromodulation techniques show promise in improving certain cognitive domains among patients with schizophrenia spectrum disorders. Understanding the mechanisms of neural circuits that underlie cognitive enhancement is essential for elucidating the pathophysiological processes of the disorder, and these insights could significantly optimize strategies for managing schizophrenia. Meanwhile, although there is an increasing body of evidence demonstrating the therapeutic effects of neuromodulation in this area, further research is still needed, particularly regarding topics such as different treatment protocols and the long-term effects of treatment.
Surgery for an Uncommon Pathology: Pancreatic Metastases from Renal Cell Carcinoma—Indications, Type of Pancreatectomy, and Outcomes in a Single-Center Experience
Authors: Matei Emil , Ciurea Silviu , Herlea Vlad , Dumitrascu Traian , Vasilescu Catalin
Published: December 2024

Background and Objectives: The role of surgery in pancreatic metastases of renal cell carcinoma (PM_RCC) is highly controversial, particularly in the context of modern systemic therapies and the conflicting results of studies published so far. This study aims to explore a single surgical center experience (including mainly pancreatic resections) regarding the indications, the type of pancreatectomies, and early and long-term outcomes for PM_RCC. Materials and Methods: The data of all patients with surgery for PM_RCC (from 1 January 2002 to 31 December 2023) were retrospectively assessed, and potential predictors of survival were explored. Results: 20 patients underwent surgery for PM_RCC (pancreatectomies—95%). Metachronous PM_RCC was 90%, with a median interval between the initial nephrectomy and PM_RCC occurrence of 104 months. For elective pancreatectomies, the overall and severe morbidity and mortality rates were 24%, 12%, and 0%, respectively; 32% of patients underwent non-standardized pancreatic resections. The median survival of patients with negative resection margins was 128 months after pancreatectomies, with an 82% 5-year survival rate. Left kidney RCC and the body/tail PM_RCC were favorable prognostic factors for the overall survival after pancreatectomies for PM_RCC. Body/tail, asymptomatic PM_RCC, and an interval after initial nephrectomy > 2 were favorable prognostic factors for the overall survival after initial nephrectomy for RCC. Conclusions: Pancreatectomies for PM_RCC can achieve long-term survival whenever complete resection is feasible, with acceptable complication rates. Patients with left kidney RCC, body/tail, and asymptomatic PM_RCC and an interval of more than 2 years after nephrectomy exhibit the best survival rates.
An Unusual Case of Nephrotic Range Proteinuria in a Short-Standing Type 1 Diabetic Patient with Newly Diagnosed Systemic Lupus Erythematosus: A Case Report and Literature Review
Authors: Dominguez Davalos Marco , De La Flor José C. , Bedia Castillo Carlos , Lipa Chancolla Roxana , Rodríguez Tudero Celia , Apaza Jacqueline , Zamora Rocío , Cieza-Terrones Michael
Published: December 2024

Background: Lupus podocytopathy (LP) is a non-immune complex-mediated glomerular lesion in systemic lupus erythematosus (SLE), characterized by the diffuse effacement of podocyte processes without immune complex deposition or with only mesangial immune complex deposition. LP is a rare cause of nephrotic syndrome in SLE patients with implications for prognosis and treatment. Case Report: We present the case of a 28-year-old woman with a medical history of type 1 diabetes mellitus (T1DM) who presented with lower limb edema, dyspnea, hypercholesterolemia, with nephrotic range proteinuria, without acute kidney injury, and laboratory findings compatible with auto-immune hemolytic anemia. They had negative infectious serology, positive antinuclear antibody (ANA), and an eye fundus examination showing diabetic retinopathy. A biopsy was performed to define the etiology of the renal involvement, which was compatible with LP. Following immuno-suppressive and antiproteinuric therapy, the patient evolved with the complete remission of the nephrotic syndrome. Conclusions: Lupus podocytopathy is an infrequent anatomopathological entity, so this case is presented as the first reported in Peru, and a literature review is made.
Cracking Behaviour of René 80-Type Superalloy During Laser-Based Directed Energy Deposition
Authors: Klimova Margarita , Dmitrieva Anastasiia , Korsmik Rudolf , Zadykyan Grigoriy , Astakhov Ilya , Yurchenko Nikita , Zherebtsov Sergey , Stepanov Nikita , Klimova-Korsmik Olga
Published: December 2024

Features of microstructure, mechanical properties, and cracking behaviour of the René 80-type superalloy manufactured by laser-based directed energy deposition (DED-LB) have been investigated. Different cracking behaviours were observed in two thin walls fabricated by DED-LB under different conditions. The defect-free thin wall was produced at low power and scanning speed, while increasing energy input during the process led to intensive cracking. Two types of cracks that developed in the René 80-type superalloy were identified: solidification hot cracking and ductility-dip cracking (DDC), caused by σ-phase particles. It was found that transition from an equiaxed structure to a columnar one increased the susceptibility to crack propagation.
Innovative Solid-State Recycling of Aluminum Alloy AA6063 Chips Through Direct Hot Rolling Process
Authors: Carta Mauro , Ben Khalifa Noomane , Buonadonna Pasquale , El Mohtadi Rayane , Bertolino Filippo , El Mehtedi Mohamad
Published: December 2024

In this paper, the feasibility of an innovative solid-state recycling process for aluminum alloy AA6063 chips through direct rolling is studied, with the aim of offering an environmentally sustainable alternative to conventional recycling processes. Aluminum chips, produced by milling an AA6063 billet without the use of lubricants, were first compacted using a hydraulic press with a 200 kN load and subsequently heat-treated at 570 °C for 6 h. The compacted chips were directly hot-rolled through several successive passes at 490 °C. The bulk material underwent the same rolling schedule to allow comparison of the samples and assess the process, in terms of mechanical properties and microstructure. All the rolled samples were tested by tensile and microhardness tests, whereas the microstructure was observed by an optical microscope and the EBSD-SEM technique. The fracture surface of all tested samples was analyzed by SEM. Recycled samples exhibited good mechanical properties, comparable to those of the bulk material. In particular, the bulk material showed an ultimate tensile strength of 218 MPa, in contrast to 177 MPa for the recycled chips, and comparable elongation at break. This study demonstrates that direct rolling of compacted aluminum chips is both technically feasible and has environmental benefits, offering a promising approach for sustainable aluminum recycling in industrial applications within a circular economy framework.
X-Ray Diffraction Line Broadening of Irradiated Zr-2.5Nb Alloys
Authors: Griffiths Malcolm
Published: December 2024

The evolution of the mechanical properties of Zr-2.5Nb pressure tubing during irradiation is dependent on dislocation loop densities that are represented by the broadening of X-ray diffraction lines. Empirical models for the integral breadth of the diffraction peaks as a function of operating conditions have been developed to predict the mechanical properties of CANDU reactor pressure tubes as a function of fast neutron flux, time and temperature. Apart from predicting mechanical property changes based on integral breadth measurements, a new model has been developed to retrospectively deduce abnormal operating temperatures of ex-service pressure from the measured line broadening. The application of integral breadth measurements to assess mechanical properties and temperature variations in pressure tubes is described and discussed in terms of the implications for pressure tube integrity.
Resistance Element Welding (REW) of Steels with Non-Ferrous Materials: Potentials, Challenges, and Properties
Authors: Abankar Mohammad , De Maddis Manuela , Razza Valentino , Russo Spena Pasquale
Published: December 2024

Performance and functionality are two key factors in designing advanced components. One promising approach in manufacturing design is the fabrication of multi-material structures by joining dissimilar materials. Steels, known for their outstanding properties and cost-effective production, are widely used across several industries. However, their high density presents challenges when designing lightweight components. A solution lies in combining steels with lightweight, non-ferrous alloys to develop cost-effective multi-material parts. However, joining different materials is generally complex due to their different properties, making it sometimes challenging or even unfeasible. Resistance element welding (REW) offers a high-performance alternative to traditional methods, such as resistance spot welding, with a high potential in mass production industries like automotive manufacturing. This article comprehensively reviews the latest research on REW for dissimilar joining of steels and non-ferrous alloys. It focuses on the microstructural and mechanical properties of joints, innovations in the REW process, the influence of process parameters on joint quality, as well as simulation and numerical studies. In addition, REW is compared with traditional joining methods.
Assessing the Impact of Observations on the Brazilian Global Atmospheric Model (BAM) Using Gridpoint Statistical Interpolation (GSI) System
Authors: Viana Liviany Pereira , de Mattos João Gerd Zell
Published: December 2024

This article describes the main features of the impacts of global observations on the reduction of errors in the data assimilation (DA) cycle carried out in the Brazilian Global Atmospheric Model (BAM) at Center for Weather Forecast and Climate Studies [Centro de Previsão de Tempo e Estudos Climáticos (CPTEC)] at the Brazilian National Institute for Space Research [Instituto Nacional de Pesquisas Espaciais (INPE)]. These results show the importance of studying and evaluating the contribution of each observation to the DA system, therefore, two experiments (exp1/exp2) were performed with different configurations of the BAM model, with exp2 presenting the best fit between the Gridpoint Statistical Interpolation (GSI) and BAM systems. The BAM model was validated by the statistical metrics of root mean-square error and correlation anomaly, but this validation is not explored in this paper. A metric was applied that does not depend on the adjoint-based method, but only on the residuals that are made available in the GSI system for the observation space, given by the total impact, the fractional impact and the fractional beneficial impact. In general, the average daily showed that the observations of the global system that contribute most to the reduction of errors in the DA cycle are from the pilot balloon data (−3.54/−3.45 J kg−1)and the profilers (−2.13/−1.97 J kg−1), and the smallest contributions came from the land (−0.28/−0.29 J kg−1) and sea (−0.44/−0.44 J kg−1) surfaces. The same pattern was observed for the synoptic times presented. However, when verifying the fraction of the impact by each type of observation, it was found that the radiance data (64.88/30.30%), followed by radiosondes (14.85/27.42%) and satellite winds (11.03/22.70%), are the most important fractions for both experiments. These results show that the DA system is working to generate the best analyses at the research center and that the deficiencies found in some observations can be adjusted to improve the development of the GSI and the BAM model, since together, the entire database used is evaluated, as well as the forecast model itself, indicating the relationship between the assertiveness of the atmospheric model and the DA system used at the research center.
MOSFET-Based Voltage Reference Circuits in the Last Decade: A Review
Authors: Moisello Elisabetta , Bonizzoni Edoardo , Malcovati Piero
Published: December 2024

Voltage reference circuits are a basic building block in most integrated microsystems, covering a wide spectrum of applications. Hence, they constitute a subject of great interest for the entire microelectronics community. MOSFET-based solutions, in particular, have emerged as the implementation of choice for realizing voltage reference circuits, given the supply voltage scaling and the ever-lower power consumption specifications in various applications. For these reasons, this paper aims to review MOSFET-based voltage reference circuits, illustrating their principles of operation, as well as presenting a detailed overview of the state-of-the-art, in order to paint an accurate picture of the encountered challenges and proposed solutions found in the field in the last decade, thus providing a starting point for future research in the field.
Newcastle Disease Virus-Vectored African Swine Fever Virus Antigen Cocktail Delays the Onset of ASFV-SY18 but Is Not Protective
Authors: Li Qian , Jiang Yiqian , Zheng Min , Sun Xuefei , Hui Lili , Zhang Yanyan , Yue Huixian , Qi Yu , Li Siqi , Ke Junnan , Li Qixuan , Ma Boli , Jia Xiaoying , Wang Fengjie , Mi Lijuan , Zhang Shoufeng , Miao Faming , Wang Shuchao , Zhang Fei , Chen Teng , Hu Rongliang
Published: December 2024

African Swine Fever (ASF) is a highly contagious viral disease threatening the global pig industry. Currently, only two gene-deleted live attenuated vaccines are approved, exclusively in Vietnam, and their long-term effectiveness and safety are unproven, prompting the need for safer alternatives. This study assessed a cocktail of African Swine Fever Virus (ASFV) antigens delivered via a recombinant Newcastle Disease Virus (rNDV) vector against the genotype II ASFV-SY18. Antigens pB602L, pEP84R, and p22 (pKP177R) were selected based on virus neutralization and lymphocyte proliferation assays in mice and combined with capsid protein p72 (pB646L) for vaccination and challenge in pigs. The antigen cocktail delayed ASF symptoms by 3–4 days but did not prevent the lethal ASFV-SY18 infection. Significant ASFV-specific gamma interferon (IFN-γ) positive responses and NDV antibodies were detected post-inoculation, showing an induced immune response, though ASFV-specific p72 antibodies were absent. The cocktail did not cause cytokine imbalance, indicating the vector’s safety in pigs. Despite some delay in disease progression, the protection against genotype II ASFV was inadequate, underscoring the need to select more effective antigens and enhance immune responses for virus-vectored vaccines.
CRISPR-Cas-Based Pen-Side Diagnostic Tests for Anaplasma marginale and Babesia bigemina
Authors: Muriuki Robert , Ndichu Maingi , Githigia Samuel , Svitek Nicholas
Published: December 2024

Anaplasma marginale and Babesia bigemina are tick-borne pathogens, posing significant threats to the health and productivity of cattle in tropical and subtropical regions worldwide. Currently, detection of Babesia bigemina and Anaplasma marginale in infected animals relies primarily on microscopic examination of Giemsa-stained blood or organ smears, which has limited sensitivity. Molecular methods offer higher sensitivity but are costly and impractical in resource-limited settings. Following the development of a pen-side test for detecting Theileria parva infections in cattle, we have created two additional CRISPR-Cas12a assays targeting Anaplasma marginale and Babesia bigemina. The assays target the major surface protein 5 (MSP5) for A. marginale and rhoptry-associated protein 1a (RAP1a) for B. bigemina. These additional tests involve a 20 min recombinase polymerase amplification (RPA) reaction followed by a 60 min CRISPR-Cas12a detection with a lateral strip readout. Results demonstrate high specificity, with no cross-reactivity against other tick-borne parasites, and a limit of detection down to 102 DNA copies/µL of each target marker. The findings pave the way for sensitive and user-friendly pen-side tests to diagnose A. marginale and B. bigemina infections.
Release of Biopolymers from Saccharomyces cerevisiae Biomass Through Thermal and Non-Thermal Technologies
Authors: Ciccone Marianna , Khan Muhammad Rehan , Hernandez Junior Bernardo Molina , Njieukam Joel Armando , Siroli Lorenzo , Gottardi Davide , Lanciotti Rosalba , Rocculi Pietro , Patrignani Francesca
Published: December 2024

Components of yeast cell walls, such as β-glucans and mannoproteins, show promise for developing sustainable biopolymers for food packaging. Efficient extraction, however, is challenging due to the complexity of the yeast cell wall. This study explored high-pressure homogenisation (HPH) and pulsed electric fields (PEFs), alone and with heat treatment (TT), on bakery yeast (BY) and brewery spent yeast (BSY) biomasses. In the treated samples we assessed carbohydrates, proteins, β-glucans, and mannoproteins and evaluated cell wall disruption microscopically. HPH caused complete cell disintegration, enhancing intracellular release, while PEF primarily permeabilised the membranes. Combined HPH and PEF treatments significantly increased cell wall stress, leading to partial disintegration. Notably, the β-glucans released reached 3.90 g/100 g dry matter in BY and 10.44 g/100 g dry matter in BSY, demonstrating significant extraction improvements. These findings highlight the potential of HPH and PEF for enhancing β-glucan recovery from yeast biomass, offering a promising route for sustainable biopolymer production for food packaging.
Novel Betaherpesviruses in Neotropical Bats on the Caribbean Island of St. Kitts: First Report from Antillean Tree Bats (Ardops nichollsi) and Evidence for Cross-Species Transmission
Authors: Kulberg Jessica L. , Hooper Sarah , Malik Yashpal S. , Ghosh Souvik
Published: December 2024

To date, limited information is available on herpesviruses in bats from the Caribbean region. We report here high detection rates (24.24%, n = 66) of herpesviruses in oral samples from apparently healthy bats (Ardops nichollsi (75%, 9/12) and Molossus molossus (28%, 7/25)) on the Lesser Antillean Island of St. Kitts. Based on analysis of partial DNA polymerase (DPOL) sequences (~225 amino acid (aa) residues), we identified two distinct groups of herpesviruses (BO-I and -II) that were unique to A. nichollsi and M. molossus, respectively. Within the subfamily Betaherpesvirinae, the BO-I DPOL sequences shared low deduced aa identities (<70%) with other herpesviruses, and phylogenetically, they formed a distinct cluster, representing a putative novel betaherpesvirus. The BO-II DPOL sequences were closely related to a putative novel betaherpesvirus from a M. molossus in Lesser Antillean Island of Martinique, indicating possible transmission of herpesviruses by bat movement between the Caribbean Islands. Phylogenetically, the BO-I and -II betaherpesviruses exhibited species-specific (A. nichollsi and M. molossus, respectively) as well as family-specific (Phyllostomidae and Molossidae, respectively) clustering patterns, corroborating the hypothesis on host specificity of betaherpesviruses. Interestingly, a single M. molossus betaherpesvirus strain clustered with the A. nichollsi betaherpesviruses, indicating possible interspecies transmission of herpesviruses between Phyllostomidae and Molossidae. To our knowledge, this is the first report on detection of herpesviruses from Antillean tree bats (A. nichollsi), expanding the host range of betaherpesviruses. Taken together, the present study identified putative novel betaherpesviruses that might be unique to chiropteran species (A. nichollsi and M. molossus), indicating virus–host coevolution, and provided evidence for interspecies transmission of betaherpesviruses between chiropteran families.
Geosmin Events Associated with Dolichospermum circinale Abundance Promoted by Nitrogen Supply in a Chinese Large Tropical Eutrophic Reservoir
Authors: Xiao Li-Juan , Jiang Yanru , Chen Zihan , Peng Liang , Tang Yali , Lei Lamei
Published: December 2024

Taste and odor (T/O) compounds are a global threat in drinking water, mainly produced by cyanobacteria in freshwater environments. Temperature plays a crucial role in regulating geosmin dynamics in temperate and subtropical lakes, while its influence may be lower in tropical waters. To better understand the factors affecting geosmin occurrence in tropical waters, a dataset from a field investigation conducted in a large tropical reservoir was analyzed. The water temperature varied between 16 °C and 32 °C, with geosmin concentration ranging from below the detection limit (3 ng/L) to as high as 856 ng/L. Elevated geosmin levels exceeding > 10 ng/L were observed over the whole year except for in September, suggesting that the annual temperature was suitable for geosmin production. Among the diverse cyanobacteria, Dolichospermum circinale was identified as the main producer of geosmin in the reservoir, both by correlation analysis and cells’ geosmin measurements. Geosmin concentration was also significantly related to the abundance of D. circinale. None of the environmental variables (temperature, pH, transparency and nutrients) were significantly directly correlated with geosmin concentration. But the high total nitrogen significantly explained the increase in D. circinale abundance associated with geosmin elevation. Our results suggest that nutrients, particularly nitrogen, directly affected the competitive advantage and abundance of key geosmin producers and thus modified geosmin levels in this tropical reservoir. Our study thus hints at the possible management of the geosmin problem through nutrient reduction in tropical reservoirs.
Expression of Recombinant Clostridial Neurotoxin by C. tetani
Authors: Gregg Brieana M. , Gupta Sonal , Tepp William H. , Pellett Sabine
Published: December 2024

Tetanus neurotoxins (TeNT) and botulinum neurotoxins (BoNTs) are closely related ~150 kDa protein toxins that together comprise the group of clostridial neurotoxins (CNTs) expressed by various species of Clostridia. While TeNT is expressed as a single polypeptide, BoNTs are always produced alongside multiple non-toxic proteins that form a stabilizing complex with BoNT and are encoded in a conserved toxin gene cluster. It is unknown how tent evolved without a similar gene cluster and why complex-free TeNT is secreted as a stable and soluble protein by C. tetani, whereas complexing proteins appear to be essential for BoNT stability in culture supernatants of C. botulinum. To assess whether the stability of TeNT is due to an innate property of the toxin or is a result of C. tetani’s intra- and extra-cellular environment, both TeNT and complex-free BoNT/A1ERY were expressed recombinantly in atoxic C. tetani and analyzed for expression and stability. The strong clostridial ferredoxin (fdx) promotor resulted in the expression of recombinant TeNT at greater levels and earlier time points than endogenously produced TeNT. Recombinant BoNT/A1ERY was similarly expressed by atoxic C. tetani, although partial degradation was observed. The rBoNT/A1ERY produced in C. tetani was also partially proteolytically processed to the dichain form. Investigations of bacterial growth media and pH conditions found that the stability of rTeNT and rBoNT/A1ERY in spent media of C. tetani or C. botulinum was affected by growth media but not by pH. These data indicate that the distinct metabolism of C. tetani or C. botulinum under various growth conditions is a primary factor in creating a more or less favorable environment for complex-free CNT stability.
Gold and Platinum Group Element Occurrence Related to Black Shale Formations in the Southern Urals (Russia): A Review
Authors: Snachev Alexander V. , Rassomakhin Mikhail A.
Published: December 2024

This paper gives a brief description of all structural–formational zones in the Southern Urals. Riphean and Paleozoic black shale sediments with strong positive anomalies of gold and a number of other elements are widely developed within this region. This paper reports that carbonaceous shales are a very favorable geochemical environment for the primary accumulation of many industrially important elements. Under certain conditions (in the areas of magmatism, zonal metamorphism, and tectonic activity), they can serve as a source of metals and concentrate deposits, and occurrences of gold, silver, and platinoids. Among these deposits, a new type of vein-embedded gold–sulfide mineralization with dispersed gold and platinum metals, localized in rocks rich in organic carbon, has been detected. In this study, we made an attempt to summarize and systematize research materials on this issue. The presented data indicate a high potential of carbonaceous sediments in the Southern Urals, providing a good basis for further prospecting works and analytical studies.
Molecular Mechanisms and Signaling Pathways Underlying the Therapeutic Potential of Thymoquinone Against Colorectal Cancer
Authors: Majdalawieh Amin F. , Al-Samaraie Saud , Terro Tala M.
Published: December 2024

Thymoquinone (TQ), a bioactive compound derived from Nigella sativa, has garnered significant attention for its potential as a natural anti-cancer agent, particularly in the context of colorectal cancer. This review provides a detailed synthesis of the current literature on the anti-cancer properties of TQ in colorectal cancer cells, exploring both in vitro and in vivo studies to elucidate its mechanisms of action. TQ effectively induces apoptosis, inhibits cell proliferation, and reduces metastasis in colorectal cancer cells by modulating key molecular pathways such as PI3K/AKT/mTOR, NF-κB, STAT3, and MAPK. It causes mitochondrial dysfunction and activates caspases, contributing to its pro-apoptotic effects. TQ also regulates EMT and targets cancer stem cells, reducing the likelihood of metastasis. Moreover, its antioxidant properties contribute to its protective role against cancer progression. While preclinical studies provide strong evidence of TQ’s efficacy, further clinical studies are essential to establish its therapeutic potential in humans. This review underscores TQ’s promising role as a natural agent with the potential to significantly improve colorectal cancer treatment outcomes.
Emulsive Liquid–Liquid Microextraction for the Determination of Phthalic Acid Esters in Environmental Water Samples
Authors: Bi Xinyuan , Zhang Chi , Xue Xiaorong , Su Shangjun , Yang Zhiping , Jing Xu , Zhang Qiang
Published: December 2024

A convenient, rapid, and environmentally friendly method, emulsive liquid–liquid microextraction combined with high-performance liquid chromatography, was established to determine phthalic acid esters in tap, river, lake, and sea water. After the method’s optimization, we obtained the appropriate volume of the extractant and pure water, the number of strokes, the separation methods, the mass volume fraction of the demulsifier, the demulsifier volume, the sample volume, the salt amount, and the pH conditions. This method requires only 200 μL of heptanoic acid (fatty acid) as the extractant and 75 mg of sodium acetate as demulsifiers for fast microextraction and separation, respectively, avoiding the use of further equipment. Emulsive liquid–liquid microextraction offers substantial advantages over dispersive liquid–liquid microextraction by eliminating the need for toxic dispersants, thereby preventing any influences of dispersants on the partition coefficients. The linear range of detection ranged from 0.5 to 50 μg L−1, with a limit of detection of 0.2 μg L−1 and a limit of quantitation of 0.5 μg L−1. The recoveries ranged from 80.2% to 106.3%, and the relative standard deviations ranged between 0.5% and 6.7%. Five greenness metrics confirmed that this method is environmentally friendly and aligns with the principles of green analytical chemistry. The proposed method achieved a greenness score of 8.42, surpassing that of other methods as evaluated using the SPMS. The novel method may well be a valuable technique for determining phthalic acid esters in water samples.
Iridium-Catalyzed Highly Selective 1,4-Reduction of α,β-Unsaturated Carbonyl Compounds
Authors: Chen Youwei , Li Jide , Xu Jiaxi , Yang Zhanhui
Published: December 2024

In this study, an iridium-catalyzed selective 1,4-reduction of α,β-unsaturated carbonyl compounds is realized, with water as a solvent and formic acid as a hydride donor. The new efficient iridium catalyst features a 2-(4,5-dihydroimidazol-2-yl)quinoline ligand. The chemoselectivity and catalyst efficiency are highly dependent on the electronic and steric properties of the substrates. For α,β-unsaturated amides, acids, and esters, only the electron-deficient C=C bonds are reduced (1,4-reduction), and the other functional groups are left intact. The S/C ratio and initial TOF reach 7000 and 18,480 h−1, respectively. A gram-scale 1,4-reduction is also performed. Deuterium labeling shows that the β-hydrogens of the products originate from the formyl hydrogen in the formic acid. The application of the 1,4-reduction for the modification the structures of some medications is demonstrated.
Preparation and Characterization of Poly(vinyl-alcohol)/Chitosan Polymer Blend Films Chemically Crosslinked with Glutaraldehyde: Mechanical and Thermal Investigations
Authors: Pugar Daniel , Haramina Tatjana , Leskovac Mirela , Ćurković Lidija
Published: December 2024

In this study, poly(vinyl-alcohol) (PVA)/chitosan (CS) polymer blend films with different amounts of CS (0, 5, 20 and 35 wt. %) crosslinked by glutaraldehyde (GA) were prepared. The structure and properties of the prepared polymer films were studied by means of dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC), and the time-lag permeation technique. The DMA analysis showed that CS reduces the crystallinity degree of PVA, leading to a higher amount of the amorphous phase contributing to the α relaxation that corresponds to the glass-to-rubber transition. However, the mobility of the amorphous phase can be restricted with crosslinking with 1 wt. % GA. Interaction between the PVA and the CS was confirmed by DCS analysis. Additionally, the influence of the CS and crosslinking on the permeation of nitrogen molecules was investigated. The permeation was examined by the time-lag method. It was found that the addition of CS and GA to PVA improves barrier properties.
The Application of Machine Learning on Antibody Discovery and Optimization
Authors: Zheng Jiayao , Wang Yu , Liang Qianying , Cui Lun , Wang Liqun
Published: December 2024

Antibodies play critical roles in modern medicine, serving as diagnostics and therapeutics for various diseases due to their ability to specifically bind to target antigens. Traditional antibody discovery and optimization methods are time-consuming and resource-intensive, though they have successfully generated antibodies for diagnosing and treating diseases. The advancements in protein data, computational hardware, and machine learning (ML) models have the opportunity to disrupt antibody discovery and optimization research. Machine learning models have demonstrated their abilities in antibody design. These machine learning models enable rapid in silico design of antibody candidates within a few days, achieving approximately a 60% reduction in time and a 50% reduction in cost compared to traditional methods. This review focuses on the latest machine learning-based antibody discovery and optimization developments. We briefly discuss the limitations of traditional methods and then explore the machine learning-based antibody discovery and optimization methodologies. We also focus on future research directions, including developing Antibody Design AI Agents and data foundries, alongside the ethical and regulatory considerations essential for successfully adopting machine learning-driven antibody designs.
Chemistry of Materials for Energy and Environmental Sustainability
Authors: Shao Qinguo
Published: December 2024

In contemporary society, energy serves as the cornerstone of human survival and development, exerting a profound influence on the economic development of nations and the trajectory of global progress [...]
Visible Light-Driven Direct Z-Scheme Ho2SmSbO7/YbDyBiNbO7 Heterojunction Photocatalyst for Efficient Degradation of Fenitrothion
Authors: Hao Liang , Luan Jingfei
Published: December 2024

A highly versatile Z-scheme heterostructure, Ho2SmSbO7/YbDyBiNbO7 (HYO), was synthesized using an ultrasonic-assisted solvent thermal method. The HYO heterojunction, composed of dual A2B2O7 compounds, exhibits superior separation of photogenerated carriers due to its efficient Z-scheme mechanism. The synergistic properties of Ho2SmSbO7 and YbDyBiNbO7, particularly the excellent visible light absorption, enable HYO to achieve exceptional photocatalytic performance in the degradation of fenitrothion (FNT). Specifically, HYO demonstrated an outstanding removal efficiency of 99.83% for FNT and a mineralization rate of 98.77% for total organic carbon (TOC) during the degradation process. Comparative analyses revealed that HYO significantly outperformed other photocatalysts, including Ho2SmSbO7, YbDyBiNbO7, and N-doped TiO2, achieving removal rates that were 1.10, 1.20, and 2.97 times higher for FNT, respectively. For TOC mineralization, HYO exhibited even greater enhancements, with rates 1.13, 1.26, and 3.37 times higher than those of the aforementioned catalysts. Additionally, the stability and durability of HYO were systematically evaluated, confirming its potential applicability in practical scenarios. Trapping experiments and electron paramagnetic resonance analyses were conducted to identify the active species generated by HYO, specifically hydroxyl radicals (•OH), superoxide anions (•O2−), and holes (h+). This facilitated a comprehensive understanding of the degradation mechanisms and pathways associated with FNT. In conclusion, this study represents a substantial contribution to the advancement of efficient Z-scheme heterostructure and offers critical insights for the development of sustainable remediation approaches aimed at mitigating FNT contamination.
Advancements in Mass Spectrometry-Based Targeted Metabolomics and Lipidomics: Implications for Clinical Research
Authors: Anh Nguyen Ky , Thu Nguyen Quang , Tien Nguyen Tran Nam , Long Nguyen Phuoc , Nguyen Huy Truong
Published: December 2024

Targeted metabolomics and lipidomics are increasingly utilized in clinical research, providing quantitative and comprehensive assessments of metabolic profiles that underlie physiological and pathological mechanisms. These approaches enable the identification of critical metabolites and metabolic alterations essential for accurate diagnosis and precision treatment. Mass spectrometry, in combination with various separation techniques, offers a highly sensitive and specific platform for implementing targeted metabolomics and lipidomics in clinical settings. Nevertheless, challenges persist in areas such as sample collection, quantification, quality control, and data interpretation. This review summarizes recent advances in targeted metabolomics and lipidomics, emphasizing their applications in clinical research. Advancements, including microsampling, dynamic multiple reaction monitoring, and integration of ion mobility mass spectrometry, are highlighted. Additionally, the review discusses the critical importance of data standardization and harmonization for successful clinical implementation.
Antifungal Properties of Bioactive Compounds Isolated from Fucus vesiculosus Supercritical Carbon Dioxide Extract
Authors: Tyśkiewicz Katarzyna , Rüttler Felix , Tyśkiewicz Renata , Nowak Artur , Gruba Marcin , Wziątek Anita , Dębczak Agnieszka , Sandomierski Michał , Vetter Walter
Published: December 2024

The exploration of natural antifungal substances from algal origins is significant due to the increasing resistance of pathogens to conventional antifungal agents and the growing consumer demand for natural products. This manuscript represents the inaugural investigation into the antifungal attributes of bioactive compounds extracted from Fucus vesiculosus via supercritical carbon dioxide (scCO2) extraction utilizing contemporary countercurrent chromatography (CCC). In aligning with the prospective utilization of this extract within the agricultural sector, this study also serves as the preliminary report demonstrating the capability of Fucus vesiculosus scCO2 extract to enhance the activity of plant resistance enzymes. The fractions obtained through CCC were subjected to evaluation for their efficacy in inhibiting the macrospores of Fusarium culmorum. The CCC methodology facilitated the successful separation of fatty acids (reaching up to 82.0 wt.% in a given fraction) and fucosterol (attaining up to 79.4 wt.% in another fraction). All CCC fractions at the concentration of 1.0% were found to inhibit 100% of Fusarium culmorum growth. Moreover, Fucus vesiculosus scCO2 extract was able to activate plant resistance enzymes (Catalase, Ascorbic Peroxidase, Guaiacol Peroxidase, Phenylalanine Ammonia-Lyase, and Phenylalanine Ammonia-Lyase Activity).
Impact of Omega-3 on Endocannabinoid System Expression and Function, Enhancing Cognition and Behavior in Male Mice
Authors: Serrano Maitane , Saumell-Esnaola Miquel , Ocerin Garazi , García del Caño Gontzal , Puente Nagore , Sallés Joan , Rodríguez de Fonseca Fernando , Rodríguez-Arias Marta , Gerrikagoitia Inmaculada , Grandes Pedro
Published: December 2024

Background/Objectives: Omega-3 long-chain polyunsaturated fatty acids (PUFAs) support brain cell membrane integrity and help mitigate synaptic plasticity deficits. The endocannabinoid system (ECS) is integral to synaptic plasticity and regulates various brain functions. While PUFAs influence the ECS, the effects of omega-3 on the ECS, cognition, and behavior in a healthy brain remain unclear. Methods and Results: Here, we demonstrate that hippocampal synaptosomes from male mice fed an omega-3-rich diet exhibit increased levels of cannabinoid CB1 receptors (~30%), phospholipase C β1 (PLCβ1, ~30%), monoacylglycerol lipase (MAGL, ~30%), and cannabinoid receptor-interacting protein 1a (Crip1a, ~60%). Conversely, these synaptosomes show decreased levels of diacylglycerol lipase α (DAGLα, ~40%), synaptosomal-associated protein 25kDa (SNAP-25, ~30%), and postsynaptic density protein 95 (PSD-95, ~40%). Omega-3 intake also reduces Gαo and Gαi3 levels, though receptor-stimulated [35S]GTPγS binding remains unaffected. Stimulation of the medial perforant path (MPP) induced long-term potentiation (LTP) in omega-3-fed mice. This LTP was dependent on group I metabotropic glutamate receptors (mGluR), 2 arachidonoylglycerol (2-AG), CB1 receptors, N-type Ca2+ channels, and actin filaments. Behaviorally, omega-3-fed mice displayed reduced exploratory behavior and significantly improved object discrimination in the novel object recognition test (NORT). They also spent more time in open arms and exhibited reduced freezing time in the elevated plus maze (EPM), indicative of reduced anxiety-like behavior. Conclusions: Our findings suggest that omega-3 leverages the ECS to enhance brain function under normal conditions.