bluuebunny/crossref_metadata_2025 huggingface dataset:
Changes in the Urine Metabolomic Profile in Patients Recovering from Severe COVID-19
Authors: Rosolanka Robert , Liptak Peter , Baranovicova Eva , Bobcakova Anna , Vysehradsky Robert , Duricek Martin , Kapinova Andrea , Dvorska Dana , Dankova Zuzana , Simekova Katarina , Lehotsky Jan , Halasova Erika , Banovcin Peter
Published: March 2023

Metabolomics is a relatively new research area that focuses mostly on the profiling of selected molecules and metabolites within the organism. A SARS-CoV-2 infection itself can lead to major disturbances in the metabolite profile of the infected individuals. The aim of this study was to analyze metabolomic changes in the urine of patients during the acute phase of COVID-19 and approximately one month after infection in the recovery period. We discuss the observed changes in relation to the alterations resulting from changes in the blood plasma metabolome, as described in our previous study. The metabolome analysis was performed using NMR spectroscopy from the urine of patients and controls. The urine samples were collected at three timepoints, namely upon hospital admission, during hospitalization, and after discharge from the hospital. The acute COVID-19 phase induced massive alterations in the metabolic composition of urine was linked with various changes taking place in the organism. Discriminatory analyses showed the feasibility of successful discrimination of COVID-19 patients from healthy controls based on urinary metabolite levels, with the highest significance assigned to citrate, Hippurate, and pyruvate. Our results show that the metabolomic changes persist one month after the acute phase and that the organism is not fully recovered.
The Effect of Defect Charge and Parasitic Surface Conductance on Aluminum Nitride RF Filter Circuit Loss
Authors: Xu Tian , Zou Yali , Huang Xuan , Wu Junmin , Wu Shihao , Liu Yuhao , Xu Xuankai , Liu Fengyu
Published: March 2023

When AlN thin films are deposited directly on the high-resistance silicon (HR-Si) substrate, a conductive layer will be formed on the HR-Si surface. This phenomenon is called the parasitic surface conduction (PSC) effect. The presence of the PSC effect will increase the power consumption of electronic components. Therefore, it is necessary to reduce the PSC effect. In prior technology, the polysilicon layer is usually used as the trap-rich layer to reduce the PSC effect. Experiments show that compared to AlN films deposited directly on HR-Si, the AlN substrates with polysilicon introduced on HR-Si have less radio frequency (RF) loss. To verify the effect of polysilicon on RF loss, polysilicon films of three different thicknesses and several different roughnesses were introduced. The results show that the thickness of the polysilicon will affect the RF loss, while the roughness has almost no effect on it. The polysilicon trap-rich layer can reduce the RF loss, which gradually becomes smaller as the polysilicon thickness increases.
Research on Chemical Mechanical Polishing Technology for Zirconium-Based Amorphous Alloys
Authors: Hang Wei , Song Chao , Yin Ziliang , Liu Ye , Wang Qifan , Wang Yinggang , Ma Yi , Zeng Qiaoshi
Published: March 2023

Crystallization often occurs in the processing of amorphous alloys, causing the materials lose their excellent properties. The study adopts chemical mechanical polishing of amorphous alloys, presenting the effect of the rotational speed of the polishing turntable, size of abrasive, polishing pressure, and oxidant concentration. The Taguchi method is used to find the best processing parameters, and AFM is used to characterize the machined material surface. At the same time, XPS is used to detect the change of oxide film composition with the addition of oxidant. The results indicate the optimum process parameters: rotational speed of the polishing turntable is 75 r/min, polishing pressure is 28.3 kPa, the size of abrasive is 0.5 μm, and the size of abrasive is a significant factor affecting surface roughness Sa. In addition, as the size of abrasive increases, the material removal rate increases while the surface roughness Sa increases. At pH 10, with an abrasive particle size of 0.5 μm, as the H2O2 concentration increases, the MRR first rapidly decreases at 0.21 wt.% H2O2, and then gradually increases, while the Sa decreases. Furthermore, with the addition of oxidant, the main composition of the surface oxide film changes from oxide to hydroxide, and the contents of Zr4+ and Cu0/Cu1+ elements increase. The findings can provide a feasible chemical mechanical polishing process for zirconium-based amorphous alloys to obtain a satisfactory polishing effect.
Bandwidth and Gain Enhancement of a CPW Antenna Using Frequency Selective Surface for UWB Applications
Authors: Hussain Musa , Sufian Md. Abu , Alzaidi Mohammed S. , Naqvi Syeda Iffat , Hussain Niamat , Elkamchouchi Dalia H. , Sree Mohamed Fathy Abo , Fatah Sara Yehia Abdel
Published: March 2023

In this article, a single-layer frequency selective surface (FSS)-loaded compact coplanar waveguide (CPW)-fed antenna is proposed for very high-gain and ultra-wideband applications. At the initial stage, a geometrically simple ultra-wideband (UWB) antenna is designed which contains CPW feed lines and a multi-stub-loaded hexagonal patch. The various stubs are inserted to improve the bandwidth of the radiator. The antenna operates at 5–17 GHz and offers 6.5 dBi peak gain. Subsequently, the proposed FSS structure is designed and loaded beneath the proposed UWB antenna to improve bandwidth and enhance gain. The antenna loaded with FSS operates at an ultra-wideband of 3–18 GHz and offers a peak gain of 10.5 dBi. The FSS layer contains 5 × 5 unit cells with a total dimension of 50 mm × 50 mm. The gap between the FSS layer and UWB antenna is 9 mm, which is fixed to obtain maximum gain. The proposed UWB antenna and its results are compared with the fabricated prototype to verify the results. Moreover, the performance parameters such as bandwidth, gain, operational frequency, and the number of FSS layers used in the proposed antenna are compared with existing literature to show the significance of the proposed work. Overall, the proposed antenna is easy to fabricate and has a low profile and simple geometry with a compact size while offering a very wide bandwidth and high gain. Due to all of its performance properties, the proposed antenna system is a strong candidate for upcoming wideband and high-gain applications.
Properties of Fine-Grained Rock Waste from the Pilawa Gorna Amphibolite and Migmatite Aggregates Production Plant
Authors: Duchnowska Magdalena , Bakalarz Alicja , Luszczkiewicz Andrzej
Published: March 2023

In the course of mining and processing of almost all petrographic varieties of rock raw materials for the production of building and materials, aggregates for road and railway construction, waste is generated. These are usually fine-grained fractions of these rocks that are difficult to manage and are deposited at dumps. The article presents and describes the results of the physical, chemical, and mineralogical properties of fine-grained waste from the production of amphibolite aggregate from Pilawa Gorna in Lower Silesia (S-W Poland). Such studies have not been carried out on this waste before. The tested waste is a very fine-grained dusty material (<0.100 mm) originating from the dedusting of the crushing and classification operations during the production of aggregates. Preliminary studies of the separation of the tested material using collector-less flotation and gravity separation are also presented. Detailed chemical analysis shows that most of the elements in the studied rock dust occur in abundance close to the average in the Earth’s crust. The collector-free flotation of the investigated sample allows effective separation of graphite and the part of sulfide minerals Cu, Ni, and Mo. The presented results may be the basis for further research and development of the concept of their economic use.
Preparation of Cu/Sn-Organic Nano-Composite Catalysts for Potential Use in Hydrogen Evolution Reaction and Electrochemical Characterization
Authors: Khdary Nezar H. , El Enany Gaber , Almalki Amani S. , Alhassan Ahmed M. , Altamimi Abdullah , Alshihri Saeed
Published: March 2023

In this work, the solvothermal solidification method has been used to be prepared as a homogenous CuSn-organic nano-composite (CuSn-OC) to use as a catalyst for alkaline water electrolysis for cost-effective H2 generation. FT-IR, XRD, and SEM techniques were used to characterize the CuSn-OC which confirmed the formation of CuSn-OC with a terephthalic acid linker as well as Cu-OC and Sn-OC. The electrochemical investigation of CuSn-OC onto a glassy carbon electrode (GCE) was evaluated using the cyclic voltammetry (CV) method in 0.1 M KOH at room temperature. The thermal stability was examined using TGA methods, and the Cu-OC recorded a 91.4% weight loss after 800 °C whereas the Sn-OC and CuSn-OC recorded 16.5 and 62.4%, respectively. The results of the electroactive surface area (ECSA) were 0.5, 0.42, and 0.33 m2 g−1 for the CuSn-OC, Cu-OC, and Sn-OC, respectively, and the onset potentials for HER were −420, −900, and −430 mV vs. the RHE for the Cu-OC, Sn-OC, and CuSn-OC, respectively. LSV was used to evaluate the electrode kinetics, and the Tafel slope for the bimetallic catalyst CuSn-OC was 190 mV dec−1, which was less than for both the monometallic catalysts, Cu-OC and Sn-OC, while the overpotential was −0.7 vs. the RHE at a current density of −10 mA cm−2.
Whey Protein Hydrolysate Renovates Age-Related and Scopolamine-Induced Cognitive Impairment
Authors: Ding Ning , Meng Hanxiu , Wu Chao , Yokoyama Wallace , Hong Hui , Luo Yongkang , Tan Yuqing
Published: March 2023

Whey protein and its hydrolysates are ubiquitously applied in the food system. However, their effect on cognitive impairment remains unclear. This study aimed to investigate the potential ability of whey protein hydrolysate (WPH) to ameliorate cognitive degeneration. WPH intervention in Crl:CD1 (ICR, Institute for cancer research) mice and aged C57BL/6J mice in a scopolamine-induced cognitive impairment model for 10 days were evaluated. Behavioral tests indicated that WPH intervention improved the cognitive abilities in ICR and aged C57BL/6J mice (p < 0.05). Scopolamine enhanced the Aβ1-42 level in the brain tissue, and the WPH intervention exhibited a similar therapeutic effect to donepezil in ICR mice. A noticeable reduction occurred in serum Aβ1-42 level of aged mice treated with WPH. The histopathological study of the hippocampus showed that WPH intervention alleviates neuronal damage. Hippocampus proteomic analysis suggested possible mechanisms of WPH action. The relative abundance of Christensenellaceae, a gut microbe related to Alzheimer’s disease, was altered by WPH intervention. This study demonstrated that short-term WPH intake protected against memory impairment induced by scopolamine and aging.
Body Mass Index Measured Repeatedly over 42 Years as a Risk Factor for Ischemic Stroke: The HUNT Study
Authors: Horn Jens W. , Feng Tingting , Mørkedal Bjørn , Aune Dagfinn , Strand Linn Beate , Horn Julie , Mukamal Kenneth J. , Janszky Imre
Published: March 2023

Background: Higher BMI in middle age is associated with ischemic stroke, but little is known about BMI over adulthood, and the risk for ischemic stroke as most studies relied on a single measurement of BMI. Methods: BMI was measured four times over a period of 42 years. We calculated average BMI values and group-based trajectory models and related these to the prospective risk of ischemic stroke after the last examination in Cox models with a follow-up time of 12 years. Results: A total of 14,139 participants, with a mean age of 65.2 years and 55.4% women, had information on BMI from all four examinations, and we observed 856 ischemic strokes. People with overweight and obesity over adulthood had a higher risk for ischemic stroke with a multivariable-adjusted hazard ratio of 1.29 (95% CI 1.11−1.48) and 1.27 (95% CI 0.96−1.67), respectively, when compared to normal weight participants. Excess weight tended to have stronger effects earlier than later in life. A trajectory of developing obesity throughout life was associated with higher risk than other trajectories. Conclusions: High average BMI, especially at an early age, is a risk factor for ischemic stroke. Early weight control and long-term weight reduction for those with high BMI may decrease the later occurrence of ischemic stroke.
Effectiveness of Apigenin, Resveratrol, and Curcumin as Adjuvant Nutraceuticals for Calvarial Bone Defect Healing: An In Vitro and Histological Study on Rats
Authors: Lorusso Felice , Scarano Antonio , Fulle Stefania , Valbonetti Luca , Mancinelli Rosa , Di Filippo Ester Sara
Published: March 2023

Bone healing is a major clinical issue, especially in bone defects of critical dimensions. Some studies have reported in vivo positive effects on bone healing by some bioactive compounds, such as the phenolic derivatives found in vegetables and plants, such as resveratrol, curcumin, and apigenin. The aim of this work was (1) to analyze in vitro in human dental pulp stem cells the effects of these three natural compounds on the gene expression of related genes downstream to RUNX2 and SMAD5, key factor transcriptions associated with osteoblast differentiation, in order to better understand the positive effects that can occur in vivo in bone healing, and (2) to evaluate in vivo the effects on bone healing of critical-size defects in the calvaria in rats of these three nutraceuticals tested in parallel and for the first time administered by the gastric route. Upregulation of the RUNX2, SMAD5, COLL1, COLL4, and COLL5 genes in the presence of apigenin, curcumin, and resveratrol was detected. In vivo, apigenin induced more consistent significant bone healing in critical-size defects in rat calvaria compared to the other study groups. The study findings encourage a possible therapeutic supplementation with nutraceuticals during the bone regeneration process.
Bacterial and Viral Pathogens with One Health Relevance in Invasive Raccoons (Procyon lotor, Linné 1758) in Southwest Germany
Authors: Reinhardt Nico P. , Köster Judith , Thomas Astrid , Arnold Janosch , Fux Robert , Straubinger Reinhard K.
Published: March 2023

In Europe, raccoons are invasive neozoons with their largest population in Germany. Globally, this mesocarnivore acts as a wildlife reservoir for many (non-)zoonotic (re-)emerging pathogens, but very little epidemiological data is available for southwest Germany. This exploratory study aimed to screen free-ranging raccoons in Baden-Wuerttemberg (BW, Germany) for the occurrence of selected pathogens with One Health relevance. Organ tissue and blood samples collected from 102 animals, obtained by hunters in 2019 and 2020, were subsequently analysed for two bacterial and four viral pathogens using a qPCR approach. Single samples were positive for the carnivore protoparvovirus-1 (7.8%, n = 8), canine distemper virus (6.9%, n = 7), pathogenic Leptospira spp. (3.9%, n = 4) and Anaplasma phagocytophilum (15.7%, n = 16). West Nile virus and influenza A virus were not detected. Due to their invasive behaviour and synanthropic habit, raccoons may increase the risk of infections for wildlife, domestic animals, zoo animals and humans by acting as a link between them. Therefore, further studies should be initiated to evaluate these risks.
Type I Cystatin Derived from Fasciola gigantica Suppresses Macrophage-Mediated Inflammatory Responses
Authors: Chantree Pathanin , Tarasuk Mayuri , Prathaphan Parisa , Ruangtong Jittiporn , Jamklang Mantana , Chumkiew Sirilak , Martviset Pongsakorn
Published: March 2023

There is an inverse relationship between the high incidence of helminth infection and the low incidence of inflammatory disease. Hence, it may be that helminth molecules have anti-inflammatory effects. Helminth cystatins are being extensively studied for anti-inflammatory potential. Therefore, in this study, the recombinant type I cystatin (stefin-1) of Fasciola gigantica (rFgCyst) was verified to have LPS-activated anti-inflammatory potential, including in human THP-1-derived macrophages and RAW 264.7 murine macrophages. The results from the MTT assay suggest that rFgCyst did not alter cell viability; moreover, it exerted anti-inflammatory activity by decreasing the production of proinflammatory cytokines and mediators, including IL-1β, IL-6, IL-8, TNF-α, iNOS, and COX-2 at the gene transcription and protein expression levels, as determined by qRT-PCR and Western blot analysis, respectively. Further, the secretion levels of IL-1β, IL-6, and TNF-α determined by ELISA and the NO production level determined by the Griess test were decreased. Furthermore, in Western blot analysis, the anti-inflammatory effects involved the downregulation of pIKKα/β, pIκBα, and pNF-κB in the NF-κB signaling pathway, hence reducing the translocation from the cytosol into the nucleus of pNF-κB, which subsequently turned on the gene of proinflammatory molecules. Therefore, cystatin type 1 of F. gigantica is a potential candidate for inflammatory disease treatment.
Characterization of Lemon Pepper and Black Ginger Extracts and Macroemulsions as Natural Pain Relievers for Spice Stick Balsam Formulation
Authors: Yanti  , Harijono Celinia , Lay Bibiana Widiyati
Published: March 2023

Lemon pepper or andaliman (Zanthoxylum acanthopodium) and black ginger (Kaempferia parviflora) are rich in bioactive compounds that possess antioxidant and anti-inflammatory activities. Our recent study demonstrated that andaliman ethanolic extract also exerted anti-arthritic and anti-inflammatory effects in arthritic mice in vivo. Therefore, natural anti-inflammatory and anti-arthritic compounds for alternative natural pain relievers in balsam formulation are needed. This study aimed to produce and characterize lemon pepper and black ginger extracts and their macroemulsion products, followed by formulation, characterization, and stability of spice stick balsam products containing lemon pepper and black ginger macroemulsions. The extraction yields obtained were 24% w/w for lemon pepper and 59% w/w for black ginger. GC/MS results showed that the lemon pepper extract contained limonene and geraniol compounds, and black ginger extract contained gingerol, shogaol, and tetramethoxyflavone compounds. Spice extracts were successfully made in the form of a stable emulsion. The antioxidant activity in both spice extracts and emulsions was relatively high (>50%). The five stick balsam formulas obtained had a pH of 5, 4.5–4.8 cm spread ability, and 30–50 s of adhesion. The stability of products showed no microbial contamination. Based on the organoleptic results, the stick balsam formula of black ginger and black ginger: lemon pepper (1:3) was the most preferred by the panelists. In conclusion, lemon pepper and black ginger extracts and macroemulsions could be used as natural pain relievers in stick balsam products to promote health protection.
First Evidence of Activity of Enfortumab Vedotin on Brain Metastases in Urothelial Cancer Patients
Authors: Vulsteke Christof , De Cocker Laurens , Gómez de Liaño Alfonso , Montesdeoca Cristina , De Meulenaere Astrid , Croes Lieselot , Delombaerde Danielle , Szabados Bernadett , Powles Thomas
Published: March 2023

Enfortumab vedotin (EV), an antibody–drug conjugate directed against Nectin-4, significantly prolonged survival compared to standard chemotherapy in patients with locally advanced or metastatic urothelial carcinoma who previously received platinum-based chemotherapy and a PD-1 or PD-L1 inhibitor. The overall response rate in the phase 3 EV301 trial leading to approval was 40.6%. However, no data have been published yet regarding the effect of EV on brain metastases. Here, we present three patients from different centers with brain metastases receiving EV. A 58-year-old white male patient, who had been heavily pretreated for urothelial carcinoma with visceral metastases and a solitary clinically active brain metastasis, started on EV 1.25 mg/kg on days 1, 8, and 15 of a 28-day cycle. After three cycles, the first evaluation showed a partial remission by RECIST v1.1, with a near complete response on the brain metastasis and disappearance of neurological symptoms. The patient is currently still receiving EV. A second, 74-year-old male patient started on the same regimen, after previous progression on platinum-based chemotherapy and avelumab in maintenance. The patient achieved a complete response and received therapy for five months. Nevertheless, therapy was discontinued at the patient’s request. Shortly after, he developed new leptomeningeal metastases. Upon rechallenge with EV, there was a significant reduction in the diffuse meningeal infiltration. A third, 50-year-old white male patient also received EV after previous progression on cisplatin–gemcitabine and atezolizumab maintenance, followed by palliative whole-brain radiotherapy and two cycles of vinflunine. After three cycles of EV, there was a significant reduction in the brain metastases. The patient is currently still receiving EV. These are the first reports on the efficacy of EV in patients with urothelial carcinoma and active brain metastases.
Overview of Side-Effects of Antibacterial Fluoroquinolones: New Drugs versus Old Drugs, a Step Forward in the Safety Profile?
Authors: Rusu Aura , Munteanu Alexandra-Cristina , Arbănași Eliza-Mihaela , Uivarosi Valentina
Published: March 2023

Antibacterial fluoroquinolones (FQs) are frequently used in treating infections. However, the value of FQs is debatable due to their association with severe adverse effects (AEs). The Food and Drug Administration (FDA) issued safety warnings concerning their side-effects in 2008, followed by the European Medicine Agency (EMA) and regulatory authorities from other countries. Severe AEs associated with some FQs have been reported, leading to their withdrawal from the market. New systemic FQs have been recently approved. The FDA and EMA approved delafloxacin. Additionally, lascufloxacin, levonadifloxacin, nemonoxacin, sitafloxacin, and zabofloxacin were approved in their origin countries. The relevant AEs of FQs and their mechanisms of occurrence have been approached. New systemic FQs present potent antibacterial activity against many resistant bacteria (including resistance to FQs). Generally, in clinical studies, the new FQs were well-tolerated with mild or moderate AEs. All the new FQs approved in the origin countries require more clinical studies to meet FDA or EMA requirements. Post-marketing surveillance will confirm or infirm the known safety profile of these new antibacterial drugs. The main AEs of the FQs class were addressed, highlighting the existing data for the recently approved ones. In addition, the general management of AEs when they occur and the rational use and caution of modern FQs were outlined.
Ginsenosides and Biotic Stress Responses of Ginseng
Authors: Goodwin Paul H. , Best Madison A.
Published: March 2023

Ginsenosides are saponins that possess a sugar moiety attached to a hydrophobic aglycone triterpenoid. They have been widely studied for their various medicinal benefits, such as their neuroprotective and anti-cancer activities, but their role in the biology of ginseng plants has been much less widely documented. In the wild, ginsengs are slow-growing perennials with roots that can survive for approximately 30 years; thus, they need to defend themselves against many potential biotic stresses over many decades. Biotic stresses would be a major natural selection pressure and may at least partially explain why ginseng roots expend considerable resources in order to accumulate relatively large amounts of ginsenosides. Ginsenosides may provide ginseng with antimicrobial activity against pathogens, antifeedant activity against insects and other herbivores, and allelopathic activity against other plants. In addition, the interaction of ginseng with pathogenic and non-pathogenic microorganisms and their elicitors may trigger increases in different root ginsenosides and associated gene expression, although some pathogens may be able to suppress this behavior. While not covered in this review, ginsenosides also have roles in ginseng development and abiotic stress tolerance. This review shows that there is considerable evidence supporting ginsenosides as important elements of ginseng’s defense against a variety of biotic stresses.
Experimental Research of Abnormal Wear for Water-Lubricated Polymer Bearings under Low Speed, Heavy Pressure, and High Water Temperature
Authors: Liu Ying , Gao Gengyuan , Jiang Dan
Published: March 2023

Polymer bearings used in a real ship had a hydrolysis failure under 50 rpm at 0.5 MPa with 40 °C water temperature. The test conditions were determined based on the operating conditions of the real ship. The test equipment was rebuilt to accommodate bearing sizes in a real ship. Water swelling was eliminated after 6 months’ soaking. The results showed that the polymer bearing was subjected to hydrolysis because of the increased heat generation and heat dissipation deterioration under low speed, heavy pressure, and high water temperature. The wear depth in the hydrolysis area is 10 times larger than that in normal wear area, and the melting, stripping, transferring, adhering, and accumulation of hydrolyzed polymers caused abnormal wear. Additionally, extensive cracking was observed in the hydrolysis area of the polymer bearing.
Modelling of Nonthermal Dielectric Barrier Discharge Plasma at Atmospheric Pressure and Role of Produced Reactive Species in Surface Polymer Microbial Purification
Authors: Elaissi Samira , Alsaif Norah A. M.
Published: March 2023

A nonthermal atmospheric plasma reactor was used to sterilize polymer surfaces and satisfy safety constraints in a biological medium. A 1D fluid model was developed using COMSOL Multiphysics software® 5.4 with a helium–oxygen mixture at low temperature for the decontamination of bacteria on polymer surfaces. An analysis of the evolution of the homogeneous dielectric barrier discharge (DBD) was carried out through studying the dynamic behavior of the discharge parameters including the discharge current, the consumed power, the gas gap voltage, and transport charges. In addition, the electrical characteristics of a homogeneous DBD under different operating conditions were studied. The results shown that increasing voltage or frequency caused higher ionization levels and maximum increase of metastable species’ density and expanded the sterilization area. On the other hand, it was possible to operate plasma discharges at a low voltage and a high density of plasma using higher values of the secondary emission coefficient or permittivity of the dielectric barrier materials. When the discharge gas pressure increased, the current discharges declined, which indicated a lower sterilization efficiency under high pressure. A short gap width and the admixture of oxygen were needed for sufficient bio-decontamination. Plasma-based pollutant degradation devices could therefore benefit from these results.
Effects of pH and Crosslinking Agent in the Evaluation of Hydrogels as Potential Nitrate-Controlled Release Systems
Authors: Ureña-Amate María Dolores , Socias-Viciana María del Mar , Urbano-Juan María del Mar , García-Alcaraz María del Carmen
Published: March 2023

Water scarcity and the loss of fertilizer from agricultural soils through runoff, which also leads to contamination of other areas, are increasingly common problems in agriculture. To mitigate nitrate water pollution, the technology of controlled release formulations (CRFs) provides a promising alternative for improving the management of nutrient supply and decreasing environmental pollution while maintaining good quality and high crop yields. This study describes the influence of pH and crosslinking agent, ethylene glycol dimethacrylate (EGDMA) or N,N′-methylenebis (acrylamide) (NMBA), on the behavior of polymeric materials in swelling and nitrate release kinetics. The characterization of hydrogels and CRFs was performed by FTIR, SEM, and swelling properties. Kinetic results were adjusted to Fick, Schott, and a novel equation proposed by the authors. Fixed-bed experiments were carried out by using the NMBA systems, coconut fiber, and commercial KNO3. Results showed that on the one hand, no significant differences were observed in nitrate release kinetics for any system in the selected pH range, this fact allowing to apply these hydrogels to any type of soil. On the other hand, nitrate release from SLC-NMBA was found to be a slower and longer process versus commercial potassium nitrate. These features indicate that the NMBA polymeric system could potentially be applied as a controlled release fertilizer suitable for a wide variety of soil typologies.
Aging of Industrial Polypropylene Surfaces in Detergent Solution and Its Consequences for Biofilm Formation
Authors: Cremer Julian , Kaltschmidt Bernhard P. , Kiel Annika , Eberhard Jens , Schmidt Stephan , Kaltschmidt Christian , Kaltschmidt Barbara , Hütten Andreas , Anselmetti Dario
Published: March 2023

The performance of plastic components in water-bearing parts of industrial and household appliances, often in the presence of harsh environments and elevated temperatures, critically relies on the mechanical and thermal polymer stability. In this light, the precise knowledge of aging properties of polymers formulated with dedicated antiaging additive packages as well as various fillers is crucial for long-time device warranty. We investigated and analysed the time-dependent, polymer-liquid interface aging of different industrial performance polypropylene samples in aqueous detergent solution at high temperatures (95 °C). Special emphasis was put on the disadvantageous process of consecutive biofilm formation that often follows surface transformation and degradation. Atomic force microscopy, scanning electron microscopy, and infrared spectroscopy were used to monitor and analyse the surface aging process. Additionally, bacterial adhesion and biofilm formation was characterised by colony forming unit assays. One of the key findings is the observation of crystalline, fibre-like growth of ethylene bis stearamide (EBS) on the surface during the aging process. EBS is a widely used process aid and lubricant enabling the proper demoulding of injection moulding plastic parts. The aging-induced surface-covering EBS layers changed the surface morphology and promoted bacterial adhesion as well as biofilm formation of Pseudomonas aeruginosa.
On the Addition of Multifunctional Methacrylate Monomers to an Acrylic-Based Infusible Resin for the Weldability of Acrylic-Based Glass Fibre Composites
Authors: Perrin Henri , Bodaghi Masoud , Berthé Vincent , Vaudemont Régis
Published: March 2023

The melt strength of Elium® acrylic resin is an important factor to ensure limited fluid flow during welding. To provide Elium® with a suitable melt strength via a slight crosslink, this study examines the effect of two dimethacrylates, namely butanediol-di-methacrylate (BDDMA) and tricyclo-decane-dimethanol-di-methacrylate (TCDDMDA), on the weldability of acrylic-based glass fibre composites. The resin system impregnating a five-layer woven glass preform is a mixture of Elium® acrylic resin, an initiator, and each of the multifunctional methacrylate monomers in the range of 0 to 2 parts per hundred resin (phr). Composite plates are manufactured by vacuum infusion (VI) at an ambient temperature and welded by using the infrared (IR) welding technique. The mechanical thermal analysis of the composites containing multifunctional methacrylate monomers higher than 0.25 phr shows a very little strain for the temperature range of 50 °C to 220 °C. The quantity of 0.25 phr of both of the multifunctional methacrylate monomers in the Elium® matrix improves the maximum bound shear strength of the weld by 50% compared to those compositions without the multifunctional methacrylate monomers.
Comparative Study of Green and Traditional Routes for Cellulose Extraction from a Sugarcane By-Product
Authors: Casanova Francisca , Freixo Ricardo , Pereira Carla F. , Ribeiro Alessandra B. , Costa Eduardo M. , Pintado Manuela E. , Ramos Óscar L.
Published: March 2023

Sugarcane bagasse (SCB) is the main residue of the sugarcane industry and a promising renewable and sustainable lignocellulosic material. The cellulose component of SCB, present at 40–50%, can be used to produce value-added products for various applications. Herein, we present a comprehensive and comparative study of green and traditional approaches for cellulose extraction from the by-product SCB. Green methods of extraction (deep eutectic solvents, organosolv, and hydrothermal processing) were compared to traditional methods (acid and alkaline hydrolyses). The impact of the treatments was evaluated by considering the extract yield, chemical profile, and structural properties. In addition, an evaluation of the sustainability aspects of the most promising cellulose extraction methods was performed. Among the proposed methods, autohydrolysis was the most promising approach in cellulose extraction, yielding 63.5% of a solid fraction with ca. 70% cellulose. The solid fraction showed a crystallinity index of 60.4% and typical cellulose functional groups. This approach was demonstrated to be environmentally friendly, as indicated by the green metrics assessed (E(nvironmental)-factor = 0.30 and Process Mass Intensity (PMI) = 20.5). Autohydrolysis was shown to be the most cost-effective and sustainable approach for the extraction of a cellulose-rich extract from SCB, which is extremely relevant for aiming the valorization of the most abundant by-product of the sugarcane industry.
Coulomb Spike Modelling of Ion Sputtering of Amorphous Water Ice
Authors: Costantini Jean-Marc , Ogawa Tatsuhiko
Published: March 2023

The effects of electronic excitations on the ion sputtering of water ice are not well understood even though there is a clear dependence of the sputtering yield on the electronic stopping power of high-energy ions. Ion sputtering of amorphous water ice induced by electronic excitations is modelled by using the Coulomb explosion approach. The momentum transfer to ionized target atoms in the Coulomb field that is generated by swift ion irradiation is computed. Positively charged ions produced inside tracks are emitted from the surface whenever the kinetic energy gained in the repulsive electrical field is higher than the surface binding energy. For that, the energy loss of deep-lying ions to reach the surface is taken into account in the sputtering yield and emitted ion velocity distribution. Monte Carlo simulations are carried out by taking into account the interactions of primary ions and secondary electrons (δ-rays) with the amorphous water ice medium. A jet-like anisotropic ion emission is found in the perpendicular direction in the angular distribution of the sputtering yield for normal incidence of 1-MeV protons. This directional emission decreases with an increasing incidence angle and vanishes for grazing incidence, in agreement with experimental data on several oxides upon swift ion irradiation. The role of the target material’s properties in this process is discussed.
On the Interpretation of Synthetic Aperture Radar Images of Oceanic Phenomena: Past and Present
Authors: Ouchi Kazuo , Yoshida Takero
Published: March 2023

In 1978, the SEASAT satellite was launched, carrying the first civilian synthetic aperture radar (SAR). The mission was the monitoring of ocean: application to land was also studied. Despite its short operational time of 105 days, SEASAT-SAR provided a wealth of information on land and sea, and initiated many spaceborne SAR programs using not only the image intensity data, but also new technologies of interferometric SAR (InSAR) and polarimetric SAR (PolSAR). In recent years, artificial intelligence (AI), such as deep learning, has also attracted much attention. In the present article, a review is given on the imaging processes and analyses of oceanic data using SAR, InSAR, PolSAR data and AI. The selected oceanic phenomena described here include ocean waves, internal waves, oil slicks, currents, bathymetry, ship detection and classification, wind, aquaculture, and sea ice.
Investigation of the Topside Ionosphere over Cyprus and Russia Using Swarm Data
Authors: Haralambous Haris , Paul Krishnendu Sekhar , Singh Arun Kumar , Gulyaeva Tamara
Published: March 2023

Using the topside electron density (Ne) measurements recorded over Cyprus and Russia, we investigate the latitudinal variation in the topside electron density during the interval 2014–2020, encompassing a period of high-to-low solar activity. The selected topside electron density dataset employed in this study is based on the in situ Langmuir probe data on board the European Space Agency (ESA) Swarm satellites, in the vicinity of the three Digisonde stations in Nicosia (35.14°N, 33.2°E), Moscow (55.5°N, 37.3°E) and Saint Petersburg (60.0°N, 30.7°E). Our investigation demonstrates that the ratio Ne_Swarm/NmF2 between the coincident Ne_Swarm and the Digisonde NmF2 observations is higher than one on various occasions over Nicosia during the nighttime, which is not the case over Moscow and Saint Petersburg, signifying a discrepancy feature of the electron density at Swarm altitudes which depends not only on the solar activity and time of day but also on the latitude.
A Channel Imbalance Calibration Scheme with Distributed Targets for Circular Quad-Polarization SAR with Reciprocal Crosstalk
Authors: Zhao Xingjie , Deng Yunkai , Zhang Heng , Liu Xiuqing
Published: March 2023

As polarimetric antennas can be isolated through excellent electronic frameworks in circular quad-polarization (CQP) synthetic aperture radar (SAR) systems, cross-polarization (x-pol) and co-polarization (co-pol) channel imbalances are more challenging and essential to calibrate than crosstalk in polarimetric calibration (PolCAL). In uncalibrated CQP SAR images without corner reflectors (CRs), the reciprocity and reflection symmetry assumptions of the distributed targets are commonly used to estimate the x-pol and co-pol channel imbalances, respectively. To suppress the influence of additive noise on determining channel imbalances through distributed targets, high signal-to-noise ratio (SNR) distributed targets should be obtained from the x-pol and co-pol channels of the CQP SAR images: namely, surface-dominated and volume-dominated targets. However, some reflection symmetry assumptions used in the existing calibration literature have poor applicability with volume-dominated targets, resulting in unsatisfactory estimation results for the co-pol channel imbalance phase. In this paper, we assess the priority of the reflection symmetry properties of volume-dominated targets used to calibrate the co-pol channel imbalance phase in CQP SAR data synthesized from linear quad-polarization data of ALOS, GF-3, and RADARSAT-2. In the theoretical part, high-priority reflection symmetry (termed semireflection symmetry) assumptions are confirmed as the most suitable for estimating the co-pol channel imbalance phase, and were selected to develop an algorithm for estimating the co-pol channel imbalance phase. Furthermore, based on the novel method for estimating the co-pol channel imbalance phase, a channel imbalance calibration scheme is proposed for CQP SAR systems with reciprocal crosstalk, including extracting surface-dominated and volume-dominated targets, and estimating and filtering channel imbalances. We demonstrate the effectiveness of our proposed scheme with CRs in simulated CQP SAR images. The experimental results show that the calibration scheme is an effective workflow for estimating channel imbalances in CQP SAR systems with reciprocal crosstalk.
Multiple Spatial and Temporal Scales Evaluation of Eight Satellite Precipitation Products in a Mountainous Catchment of South China
Authors: Guo Binbin , Xu Tingbao , Yang Qin , Zhang Jing , Dai Zhong , Deng Yunyuan , Zou Jun
Published: March 2023

Satellite precipitation products (SPPs) have emerged as an important information source of precipitation with high spatio-temporal resolutions, with great potential to improve catchment water resource management and hydrologic modelling, especially in data-sparse regions. As an indirect precipitation measurement, satellite-derived precipitation accuracy is of major concern. There have been numerous evaluation/validation studies worldwide. However, a convincing systematic evaluation/validation of satellite precipitation remains unrealized. In particular, there are still only a limited number of hydrologic evaluations/validations with a long temporal period. Here we present a systematic evaluation of eight popular SPPs (CHIRPS, CMORPH, GPCP, GPM, GSMaP, MSWEP, PERSIANN, and SM2RAIN). The evaluation area used, using daily data from 2007 to 2020, is the Xiangjiang River basin, a mountainous catchment with a humid sub-tropical monsoon climate situated in south China. The evaluation was conducted at various spatial scales (both grid-gauge scale and watershed scale) and temporal scales (annual and seasonal scales). The evaluation paid particular attention to precipitation intensity and especially its impact on hydrologic modelling. In the evaluation of the results, the overall statistical metrics show that GSMaP and MSWEP rank as the two best-performing SPPs, with KGEGrid ≥ 0.48 and KGEWatershed ≥ 0.67, while CHIRPS and SM2RAIN were the two worst-performing SPPs with KGEGrid ≤ 0.25 and KGEWatershed ≤ 0.42. GSMaP gave the closest agreement with the observations. The GSMaP-driven model also was superior in depicting the rainfall-runoff relationship compared to the hydrologic models driven by other SPPs. This study further demonstrated that satellite remote sensing still has difficulty accurately estimating precipitation over a mountainous region. This study provides helpful information to optimize the generation of algorithms for satellite precipitation products, and valuable guidance for local communities to select suitable alternative precipitation datasets.
Comparison of Higher Education in Pakistan and China: A Sustainable Development in Student’s Perspective
Authors: Raza Hasnain , Ali Anwar , Rafiq Nazia , Xing Liu , Asif Tahseen , Jing Chengjie
Published: March 2023

Education has played a central role and has had cross-cutting impact on all aspects of human life. China–Pakistan friendly relations have a long history. They cooperate in many parts of life, especially education, i.e., beneficial for better future education exchanges between countries. This study was conducted on the education systems of China and Pakistan to understand the higher education system through a student questionnaire. This research work aimed to investigate the perceptions of Pakistani and Chinese university students on sustainable development in higher education institutes (HEIs). HEIs and universities perform a unique and vital role in society by acting as intellectuals, entrepreneurs, and problem solvers. This section presents state of the art in sustainable development, the role of sustainable development in higher education, and the students’ perspectives. There were 327 questionnaires out of 400, with 27 incomplete replies being discarded, leaving us with 300 complete surveys. The literature and research theme were used to construct the hypotheses of this study. PLS-SEM, a statistical approach that utilized the partial least squares to model structural equations, was used to evaluate the hypotheses. The analysis must take into consideration all parameters. Smart PLS 3.3.9 was used for PLS-SEM analysis in this study. The results showed that quality assurance and students’ satisfaction were significant factors related to sustainable university development programs. Moreover, there was a good correlation between technological improvements in education institutes, teachers’ capacity-building programs, and student–teacher (learning–teaching) relationships. Pakistani institutions comprised 50% of the study’s participants, while students from Chinese universities comprised the remaining 50%. Among all participants, 9.66 percent of respondents were enrolled in Ph.D. programs, 37.67 percent were enrolled in an MS/M.Phil. programs, and 52.67 percent were undergraduate students. Moreover, this study also indicated that technical improvements and advancements positively correlated with sustainable development programs for Pakistani students.
Effect of Climate Smart Agriculture Innovations on Climate Resilience among Smallholder Farmers: Empirical Evidence from the Choke Mountain Watershed of the Blue Nile Highlands of Ethiopia
Authors: Teklu Abyiot , Simane Belay , Bezabih Mintewab
Published: March 2023

Smallholder farmers’ capacities need to be strengthened to enable them to better withstand the upcoming impacts of climate change; these capacities not only include the responsive capacity, but also consider innovation, learning, and anticipation to be prepared for the projected impacts of a changing climate on the agriculture system. The objective of this paper is to examine the impact of climate smart agriculture (CSA) innovations on building climate resilience capacity in smallholder agriculture systems. A cross-sectional household survey was conducted among a multi-stage sample of 424 smallholder farmers selected from five agroecosystems of the Upper Blue Nile Highlands in Ethiopia. The study used an endogenous switching regression (ESR) model to examine the impact of CSA innovations on building climate resilience capacity among smallholder farmers. The true average adoption effects of climate resilience capacity under actual and counterfactual conditions showed that different CSA innovations have different effects on the climate resilience capacity of households. Except for SWC adopters, all CSA innovations significantly increased the climate resilience capacity of households. However, improved variety, crop residue management, and SWC have more profound effects on the non-adopters than adopters, =if non-adopters had adopted these CSA innovations. Strong absorptive, adaptive, and transformative capacities through strong disaster and early warning systems, climate-resilient infrastructure, a strong public agricultural extension system, a strong informal safety net, and social networks build a climate-resilient agriculture system among smallholder farmers. Thus, scaling up of CSA innovations may expand the benefit of CSA innovation on building the climate resilience capacities of households. Thus, strong risk management, disaster mitigation and early warning systems, adaptive strategies, information and training, informal safety nets, social networks, and infrastructure use may build the climate resilience capacity of smallholder farmers by facilitating the adoption of CSA innovation. Therefore, policies that strengthen good governance, social cohesion, disaster communication and early warning systems, input supply of drought-resistant varieties, climate smart extension service, and climate-resilient infrastructure are necessary.