bluuebunny/crossref_metadata_2025 huggingface dataset:
Exercise Intervention on Insomnia in Patients with a Cancer: A Systematic Review of the Literature
Authors: Drozd Chloé , Curtit Elsa , Gillet Valérie , Jacquinot Quentin , Meneveau Nathalie , Mougin Fabienne
Published: June 2024

Cancer is associated with increased muscle weakness, reduced physical functioning, increased fatigue, but also sleep disturbances, including insomnia, that affect quality of life (QoL). Physical activity demonstrated benefits on functional capacity, resilience and cancer-related fatigue, but there is a paucity of available data regarding its effects on insomnia in patients with cancer. This systematic review aims to examine the efficacy of exercise levels with insomnia in cancer patients. A systematic search was performed for articles published in PubMed and Cochrane Library databases from December 2013 to February 2023. Included studies explored insomnia during or after cancer treatment, with various exercise interventions. The search identified nine studies included in this review. Due to substantial heterogeneity in the interventions across studies, meta-analysis was not performed. Three studies reported positive results for insomnia reduction by self-reported outcomes under a supervised aerobic exercise program alone or combined with strength training. The present systematic review establishes the role of exercise interventions for reducing cancer-related insomnia. Further studies are indeed warranted to improve the level of evidence for exercise interventions for implementation in the care of cancer-related insomnia.
Development of Traceable Mouse Models of Advanced and Metastatic Bladder Cancer
Authors: Desponds Emma , Kioseoglou Konstantina , Zdimerova Hana , Ongaro Marco , Verdeil Grégory , Leblond Marine M.
Published: June 2024

Bladder cancer (BC) is the fourth most common cancer in men, with a poor patient prognosis for advanced disease. The poor survival of patients with muscle-invasive bladder cancer (MIBC) and metastatic status emphasizes the urgent need to develop new therapies. Lacking in the field of BC is the availability of relevant advanced BC mouse models, especially metastatic ones, that accurately recapitulate the complexities of human pathology to test and study new therapeutic strategies. Addressing this need, we developed a traceable mouse model of BC that expresses tumor-associated antigens within the context of advanced muscle-invasive BC. This novel system was achieved through the deletion of the tp53 and pten genes, alongside the incorporation of the fusion construct of Firefly luciferase (Luc) and the SIYRYYGL (SIY) T-cell antigen. We validate that the presence of the transgene did not impact on the development of the tumors while allowing us to measure tumor progression by bioluminescence. We show that the transgene did not influence the composition of the immune tumor microenvironment. More importantly, we report that this model was unresponsive to anti-PD-1 treatment, as in the majority of patients with BC. We also develop a new model based on the orthotopic injection of BC clonal cell lines derived from our first model. We demonstrate that this new model invades the muscle layer and has a metastasis development rate of 83%. The advantage of this model is that we can visualize tumor growth and metastasis development in vivo. These mouse models’ characteristics, displaying many similarities with the human pathology, provide a valuable tool for tracking tumor progression, metastasis spread in vivo, and treatment resistance, as well as exploring fundamental and translational aspects of BC biology. This work contributes to the improvement in the landscape of mouse models of advanced BC for testing new therapeutic strategies.
Influence of 0.25% Indium Addition to Ni/CeO2 Catalysts for Dry Reforming of Methane
Authors: Horváth Anita , Beck Andrea , Németh Miklós , Sáfrán György , Roškarič Matevž , Žerjav Gregor , Pintar Albin
Published: June 2024

In this study, the surface and textural properties as well as the catalytic performance of Ni/CeO2 and NiIn/CeO2 catalysts prepared by wet impregnation (WI) and deposition–precipitation (DP) are investigated. The addition of Ni (3.0 wt.%) resulted in a decrease in the specific surface area and pore volume in the case of the WI method, possibly due to a blockage of mesopores. A minimal addition of In (0.25 wt.%) caused a further decrease in the surface area in both cases. XRD analysis showed that Ni deposited on CeO2 by DP resulted in some lattice incorporation, affecting the crystallinity of the support. The H2-TPR profiles altered depending on the different ways of Ni and In introduction. STEM-EDS-derived elemental maps indicated that the Ni and NiIn particles deposited on CeO2 using the DP method were somewhat smaller than in the WI synthesis. A comprehensive CO-DRIFTS analysis proved a direct Ni-In interaction in bimetallic samples, leading to the formation of a surface NiIn alloy. Ni/CeO2 catalysts showed a higher activity in the process of dry reforming of methane (DRM) than the bimetallic counterparts at 650 °C, with the Ni_DP sample performing slightly better. However, the Ni_DP catalyst showed significant coking, which was drastically reduced by the addition of In. The agglomeration of Ni and/or NiIn particles during the 6 h DRM reaction somewhat impaired the catalyst performance. Overall, this study highlights the intricate relationship between the catalyst preparation, surface properties and catalytic performance in the DRM reaction and emphasizes the beneficial role of In addition in reducing the coking of the monometallic catalyst and the critical location and surface morphology of nickel nanoparticles decorated with indium and in contact with ceria.
Methanol Reforming over Cu-Ce-Al Catalysts Prepared by Solution Combustion Synthesis Method
Authors: Assylbekov Yernur B. , Xanthopoulou Galina , Tungatarova Svetlana A. , Baizhumanova Tolkyn S. , Aubakirov Yermek A. , Zhumabek Manapkhan
Published: June 2024

The demand for environmentally friendly types of energy is growing all over the world, which naturally increases the intensity of studies on fuel mixtures that have high contents of hydrogen. In this case, methanol steam reforming is a leading effective research area, as it is a process with low energy consumption. The results of the steam reforming of methanol on synthesized catalysts by the solution combustion synthesis (SCS), self-propagating high-temperature synthesis (SHS), and moisture impregnation capacity methods are presented. A study was conducted to evaluate the activity of Cu-Ce-Al catalysts with varying ratios of components for hydrogen production, comparing the SCS method with the other mentioned methods. The methanol conversion reached 99% and the selectivity of H2 was 88% at 500 °C. The study showed that the replacement of Al3+ ions with Cu2+ and Ce3+ cations leads to the formation of spinels, such as CuAl2O4 and CeAlO3. As a consequence, the CuAl2O4 and CeAlO3 lattice parameters increase because of the difference in the ionic radii of Al3+ (0.53 Å), Cu2+ (0.73 Å), and Ce3+ (1.07 Å). Advantages of SCS catalysts in the process of the steam reforming of methanol have been demonstrated. The goal of this research is to create a new catalyst for methanol’s conversion into hydrogen-containing fuel mixtures, the production of which, in the future, will be a huge step in the transition to more energy-efficient and environmentally friendly methods of their synthesis.
Circadian Gating of Thyroid Hormone Action in Hepatocytes
Authors: Lincoln Karla , Zhou Jingxuan , Oster Henrik , de Assis Leonardo Vinicius Monteiro
Published: June 2024

Thyroid hormones, thyroxin (T4) and the biologically active triiodothyronine (T3), play important roles in liver metabolic regulation, including fatty acid biosynthesis, beta-oxidation, and cholesterol homeostasis. These functions position TH signaling as a potential target for the treatment of metabolic dysfunction-associated steatotic liver disease (MASLD). Elevated T3 levels in the circulation are associated with increased hepatic lipid turnover, which is also under the control of the circadian clock system. In this study, we developed a cell system to study the impact of hepatocyte circadian rhythms on the metabolic response to T3 treatment under control and steatotic conditions. Synchronized AML-12 circadian reporter hepatocytes were treated with T3 at different circadian phases and metabolic conditions. T3 treatment increased metabolic activity in a dose-independent fashion and had no significant effect on circadian rhythms in AML-12 cells. T3 had marked time-of-treatment-dependent effects on metabolic transcript expression. Steatosis induction altered metabolic transcript expression in AML-12 cells. In this condition, the circadian rhythm period was lengthened, and this effect was independent of T3. Under steatotic conditions, T3 had marked time-of-treatment dependent effects on metabolic transcript expression, which differed from those observed under control conditions. These findings reveal a time-of-day-dependent response of hepatocytes to T3, which is further modulated by the metabolic state. Our data suggest that time has a strong influence on liver TH action, which might be considered when treating MASLD.
Advancements in Hematopoietic Stem Cell Gene Therapy: A Journey of Progress for Viral Transduction
Authors: Giommetti Aurora , Papanikolaou Eleni
Published: June 2024

Hematopoietic stem cell (HSC) transduction has undergone remarkable advancements in recent years, revolutionizing the landscape of gene therapy specifically for inherited hematologic disorders. The evolution of viral vector-based transduction technologies, including retroviral and lentiviral vectors, has significantly enhanced the efficiency and specificity of gene delivery to HSCs. Additionally, the emergence of small molecules acting as transduction enhancers has addressed critical barriers in HSC transduction, unlocking new possibilities for therapeutic intervention. Furthermore, the advent of gene editing technologies, notably CRISPR-Cas9, has empowered precise genome modification in HSCs, paving the way for targeted gene correction. These striking progresses have led to the clinical approval of medicinal products based on engineered HSCs with impressive therapeutic benefits for patients. This review provides a comprehensive overview of the collective progress in HSC transduction via viral vectors for gene therapy with a specific focus on transduction enhancers, highlighting the latest key developments, challenges, and future directions towards personalized and curative treatments.
The Regulation of the Disease-Causing Gene FXN
Authors: Dong Yi Na , Mercado-Ayón Elizabeth , Coulman Jennifer , Flatley Liam , Ngaba Lucie Vanessa , Adeshina Miniat W. , Lynch David R.
Published: June 2024

Friedreich’s ataxia (FRDA) is a progressive neurodegenerative disease caused in almost all patients by expanded guanine–adenine–adenine (GAA) trinucleotide repeats within intron 1 of the FXN gene. This results in a relative deficiency of frataxin, a small nucleus-encoded mitochondrial protein crucial for iron–sulfur cluster biogenesis. Currently, there is only one medication, omaveloxolone, available for FRDA patients, and it is limited to patients 16 years of age and older. This necessitates the development of new medications. Frataxin restoration is one of the main strategies in potential treatment options as it addresses the root cause of the disease. Comprehending the control of frataxin at the transcriptional, post-transcriptional, and post-translational stages could offer potential therapeutic approaches for addressing the illness. This review aims to provide a general overview of the regulation of frataxin and its implications for a possible therapeutic treatment of FRDA.
A Camelid-Derived STAT-Specific Nanobody Inhibits Neuroinflammation and Ameliorates Experimental Autoimmune Encephalomyelitis (EAE)
Authors: Mbanefo Evaristus C. , Seifert Allison , Yadav Manoj Kumar , Yu Cheng-Rong , Nagarajan Vijayaraj , Parihar Ashutosh , Singh Sunanda , Egwuagu Charles E.
Published: June 2024

Proinflammatory T-lymphocytes recruited into the brain and spinal cord mediate multiple sclerosis (MS) and currently there is no cure for MS. IFN-γ-producing Th1 cells induce ascending paralysis in the spinal cord while IL-17-producing Th17 cells mediate cerebellar ataxia. STAT1 and STAT3 are required for Th1 and Th17 development, respectively, and the simultaneous targeting of STAT1 and STAT3 pathways is therefore a potential therapeutic strategy for suppressing disease in the spinal cord and brain. However, the pharmacological targeting of STAT1 and STAT3 presents significant challenges because of their intracellular localization. We have developed a STAT-specific single-domain nanobody (SBT-100) derived from camelids that targets conserved residues in Src homolog 2 (SH2) domains of STAT1 and STAT3. This study investigated whether SBT-100 could suppress experimental autoimmune encephalomyelitis (EAE), a mouse model of MS. We show that SBT-100 ameliorates encephalomyelitis through suppressing the expansion of Th17 and Th1 cells in the brain and spinal cord. Adoptive transfer experiments revealed that lymphocytes from SBT-100-treated EAE mice have reduced capacity to induce EAE, indicating that the immunosuppressive effects derived from the direct suppression of encephalitogenic T-cells. The small size of SBT-100 makes this STAT-specific nanobody a promising immunotherapy for CNS autoimmune diseases, including multiple sclerosis.
In Vivo Imaging of Immune Rejection of MIN6 Cells Transplanted in C3H Mice
Authors: Juang Jyuhn-Huarng , Chen Chen-Ling , Kao Chen-Wei , Wu Shu-Ting , Shen Chia-Rui
Published: June 2024

Recently, we successfully utilized noninvasive magnetic resonance and bioluminescence imaging to track MIN6 cells subcutaneously transplanted in immunocompromised nude mice for up to 64 days. In this study, we further used bioluminescence imaging to investigate the immune rejection of MIN6 cells in immunocompetent C3H mice. A total of 5 × 106 luciferase-transfected MIN6 cells were implanted into the subcutaneous space of each nude or C3H mouse. After transplantation, hypoglycemia and persistent bioluminescence signals were observed in eight of eight (100%) nude mice and five of nine (56%) C3H mice (p < 0.05). We then presensitized a group of C3H mice with C57BL/6 spleen cells just prior to transplantation (n = 14). Interestingly, none of them had hypoglycemia or persistent bioluminescence signals (p < 0.01 vs. C3H mice without presensitization). Histological examination of the grafts revealed a lack or minimal presence of insulin-positive cells in recipients without hypoglycemia and persistent bioluminescence signals. In contrast, recipients with hypoglycemia and persistent bioluminescence signals showed a significant presence of insulin-positive cells in their grafts. Our results indicate that rejection of MIN6 cells occurred in C3H mice and could be enhanced by presensitization with C57BL/6 spleen cells and that bioluminescence imaging is a useful noninvasive tool for detecting rejection of subcutaneously transplanted MIN6 cells.
Stem Cells and Acellular Preparations in Bone Regeneration/Fracture Healing: Current Therapies and Future Directions
Authors: Brown Marcel G. , Brady Davis J. , Healy Kelsey M. , Henry Kaitlin A. , Ogunsola Ayobami S. , Ma Xue
Published: June 2024

Bone/fracture healing is a complex process with different steps and four basic tissue layers being affected: cortical bone, periosteum, fascial tissue surrounding the fracture, and bone marrow. Stem cells and their derivatives, including embryonic stem cells, induced pluripotent stem cells, mesenchymal stem cells, hematopoietic stem cells, skeletal stem cells, and multipotent stem cells, can function to artificially introduce highly regenerative cells into decrepit biological tissues and augment the healing process at the tissue level. Stem cells are molecularly and functionally indistinguishable from standard human tissues. The widespread appeal of stem cell therapy lies in its potential benefits as a therapeutic technology that, if harnessed, can be applied in clinical settings. This review aims to establish the molecular pathophysiology of bone healing and the current stem cell interventions that disrupt or augment the bone healing process and, finally, considers the future direction/therapeutic options related to stem cells and bone healing.
Effect of Bromfenac on Reducing Neuroinflammation in an Ischemia–Reperfusion Glaucoma Model
Authors: Oh Si-Eun , Kim Jie-Hyun , Park Chan-Kee , Park Hae-Young Lopilly
Published: June 2024

In the context of glaucoma, intraocular pressure (IOP) and age are recognized as the primary factors contributing to its onset and progression. However, significant reductions in IOP fail to completely halt its advancement. An emerging body of literature highlights the role of neuroinflammation in glaucoma. This study aimed to explore Bromfenac’s anti-inflammatory properties in mitigating neuroinflammation associated with glaucoma using an ischemia–reperfusion (IR) glaucoma model. Bromfenac’s impact on microglia and astrocytes under pressure was assessed via Western blotting and an enzyme-linked immunosorbent assay. Immunohistochemical staining was used to evaluate glial activation and changes in inflammatory marker expression in the IR model. Bromfenac led to the downregulation of inflammatory markers, which were elevated in the conditions of elevated pressure, and necroptosis markers were downregulated in astrocytes. In the IR model, elevated levels of GFAP and Iba-1 indicated glial activation. Following Bromfenac administration, levels of iNOS, COX-2, and PGE2-R were reduced, suggesting a decrease in neuroinflammation. Furthermore, Bromfenac administration in the IR model resulted in the improved survival of retinal ganglion cells (RGCs) and preservation of retinal function, as demonstrated by immunohistochemical staining and electroretinography. In summary, Bromfenac proved effective in diminishing neuroinflammation and resulted in enhanced RGC survival.
Ischemic Post-Conditioning in a Rat Model of Asphyxial Cardiac Arrest
Authors: Barajas Matthew B. , Oyama Takuro , Shiota Masakazu , Li Zhu , Zaum Maximillian , Zecevic Ilija , Riess Matthias L.
Published: June 2024

Background: Ischemic post-conditioning (IPoC) has been shown to improve outcomes in limited pre-clinical models. As down-time is often unknown, this technique needs to be investigated over a range of scenarios. As this tool limits reperfusion injury, there may be limited benefit or even harm after short arrest and limited ischemia-reperfusion injury. Methods: Eighteen male Wistar rats underwent 7 min of asphyxial arrest. Animals randomized to IPoC received a 20 s pause followed by 20 s of compressions, repeated four times, initiated 40 s into cardiopulmonary resuscitation. If return of spontaneous circulation (ROSC) was achieved, epinephrine was titrated to mean arterial pressure (MAP) of 70 mmHg. Data were analyzed using t-test or Mann–Whitney test. Significance set at p ≤ 0.05. Results: The rate of ROSC was equivalent in both groups, 88%. There was no statistically significant difference in time to ROSC, epinephrine required post ROSC, carotid flow, or peak lactate at any timepoint. There was a significantly elevated MAP with IPoC, 90.7 mmHg (SD 13.9), as compared to standard CPR, 76.7 mmHg (8.5), 2 h after ROSC, p = 0.03. Conclusions: IPoC demonstrated no harm in a model of short arrest using a new arrest etiology for CPR based IPoC intervention in a rat model.
Understanding Cellular, Molecular, and Functional Specificity, Heterogeneity, and Diversity of the Endocannabinoid System
Authors: Aoki Jun , Isokawa Masako
Published: June 2024

The endocannabinoid system (ECS) is a widely recognized lipid messenger system involved in many aspects of our health and diseases [...]
Anatomical Studies Evaluating Pediatric Regional Anesthesia: A Scoping Review
Authors: Pereira Lucas Ferreira Gomes , Carlos Ricardo Vieira , van Schoor Albert , Bosenberg Adrian , Luna Natália Mariana Silva , da Costa Silva Rebeca , de Fátima Bertanha Bianca , Carmona Maria José Carvalho , Quintão Vinícius Caldeira
Published: June 2024

Background: Pediatric regional anesthesia has been driven by the gradual rise in the adoption of opioid-sparing strategies and the growing concern over the possible adverse effects of general anesthetics on neurodevelopment. Nonetheless, performing regional anesthesia studies in a pediatric population is challenging and accounts for the scarce evidence. This study aimed to review the scientific foundation of studies in cadavers to assess regional anesthesia techniques in children. Methods: We searched the following databases MEDLINE, EMBASE, and Web of Science. We included anatomical cadaver studies assessing peripheral nerve blocks in children. The core data collected from studies were included in tables and comprised block type, block evaluation, results, and conclusion. Results: The search identified 2409 studies, of which, 16 were anatomical studies on the pediatric population. The techniques evaluated were the erector spinae plane block, ilioinguinal/iliohypogastric nerve block, sciatic nerve block, maxillary nerve block, paravertebral block, femoral nerve block, radial nerve block, greater occipital nerve block, infraclavicular brachial plexus block, and infraorbital nerve block. Conclusion: Regional anesthesia techniques are commonly performed in children, but the lack of anatomical studies may result in reservations regarding the dispersion and absorption of local anesthetics. Further anatomical research on pediatric regional anesthesia may guide the practice.
Identifying Key Biomarkers in Pediatric Pulmonary Hypertension: An Investigative Approach
Authors: Mindubayeva Farida , Akhmaltdinova Lyudmila , Ospanova Mariya , Tukbekova Bibigul , Bolatbekuly Zhanat , Niyazova Yuliya , Salikhova Yelena , Avdienko Olga , Akhmetova Meruert
Published: June 2024

This study assesses the utility of early biomarkers—5-hydroxyindoleacetic acid (5-HIAA) and insulin-like growth factor 1 (IGF-1)—for diagnosing and monitoring pulmonary hypertension (PH) in children with congenital heart defects (CHD). Due to the risks associated with invasive diagnostics, such as right heart catheterization, non-invasive biomarkers provide a safer alternative for early PH detection. This cohort-based study utilized blood and urine samples to measure 5-HIAA and IGF-1 levels via enzyme immunoassays. Our findings revealed significant changes in 5-HIAA concentrations across various biological matrices, supporting its potential as a diagnostic tool. Specifically, altered levels in urine and plasma reflect its role in serotonin metabolism and vascular remodeling in PH. IGF-1 levels were notably reduced in plasma, suggesting its involvement in PH pathophysiology. ROC analysis confirmed the diagnostic efficacy of these biomarkers, particularly 5-HIAA’s high specificity and sensitivity. In conclusion, 5-HIAA and IGF-1 levels correlate well with PH, underscoring their diagnostic value for early PH detection in children with CHD.
Prevalence and Risk Factors of Healthcare-Associated Infections among Hospitalized Pediatric Patients: Point Prevalence Survey in Thailand 2021
Authors: Moolasart Visal , Srijareonvijit Chaisiri , Charoenpong Lantharita , Kongdejsakda Winnada , Anugulruengkitt Suvaporn , Kulthanmanusorn Anond , Thienthong Varaporn , Usayaporn Sang , Kaewkhankhaeng Wanwisa , Rueangna Oranat , Sophonphan Jiratchaya , Manosuthi Weerawat , Tangcharoensathien Viroj
Published: June 2024

Background: Healthcare-associated infections (HAIs) pose a grave threat to patient safety, morbidity, and mortality, contributing to antimicrobial resistance. Thus, we estimated the point prevalence, risk factors, types, and pathogens of HAIs in hospitalized pediatric patients. Methods: A point prevalence survey (PPS) of HAIs in hospitalized pediatric patients < 18 years old was conducted from March to May 2021. Outcomes, risk factors, and types of HAIs associated with HAIs in 41 hospitals across Thailand were collected. Results: The prevalence of HAIs was 3.9% (95% CI 2.9–5.0%) (56/1443). By ages < 1 month, 1 month–2 years, 2–12 years, and 12–18 years, the prevalence of HAIs was 4.2%, 3.3%, 4.1%, and 3.0%, respectively (p = 0.80). Significant independent risk factors were extended hospital length of stay (LOS) and central venous catheter (CVC) use. Compared to an LOS of <4 days, LOSs of 4–7 days, 8–14 days, and >14 days had adjusted odds ratios (aORs) of 2.65 (95% CI 1.05, 6.68), 5.19 (95% CI 2.00, 13.4), and 9.03 (95% CI 3.97, 20.5), respectively. The use of a CVC had an aOR of 2.45 (95% CI 1.06–5.66). Lower respiratory tract infection (LRTI) was the most common HAI type (46.4%: 26/56). The highest prevalence of HAIs was predominantly observed in LRTI diagnoses, with the highest among these in the <1 month age category at 2.3% (17/738). Conclusion: The prevalence of HAIs in hospitalized pediatric patients was 3.9%. Extended LOS and use of CVC were HAI risk factors. A strategy for reducing LOS and reviewing insertion indications or the early planned removal of a CVC was implemented. The surveillance of HAIs stands as a cornerstone and fundamental component of IPC, offering invaluable insights that enhance hospital IPC interventions aimed at preventing HAIs.
Finite Element Analysis Method Design and Simulation of Fins for Cooling a Monocrystalline Photovoltaic Panel
Authors: Cabrera-Escobar Raúl , Vera David , Cabrera-Escobar José , Paredes Godoy María Magdalena , Cajamarca Carrazco Diego , Zumba Llango Edwin Roberto , Jurado Francisco
Published: June 2024

This research focuses on the development and simulation analysis of heat-dissipating fins made of copper, integrated into photovoltaic panels, with the aim of mitigating temperature increases during operation. This initiative arises from evidence that solar panels experience a reduction in energy efficiency when operating at temperatures higher than standard test conditions. The photovoltaic panel was simulated both without fins and with fins under standard test conditions and extreme conditions. The simulation consists of the following steps: design, meshing, selection of physical models and materials, assignment of boundary conditions, validation of the simulation, and interpretation of the results. During validation, results obtained via simulation were compared experimentally, yielding a mean absolute percentage error of 0.28%. It was concluded that the fins with the greatest heat dissipation relative to their area are those of 40 mm height; with this height, the temperature of the photovoltaic panel is reduced by 2.64 K, which represents an efficiency increase of 1.32%. Furthermore, it was concluded from the analyzed data that the efficiency of the fins increases at high temperatures.
Long-Term Energy System Modelling for a Clean Energy Transition and Improved Energy Security in Botswana’s Energy Sector Using the Open-Source Energy Modelling System
Authors: Saad Ranea , Plazas-Niño Fernando , Cannone Carla , Yeganyan Rudolf , Howells Mark , Luscombe Hannah
Published: June 2024

This research examines Botswana’s significant reliance on coal and imported fossil fuels for electricity generation, contributing to high carbon emissions and energy insecurity influenced by volatile fuel prices and supply challenges. The study utilizes the Open-Source Energy Modelling System (OSeMOSYS) to explore cost-effective renewable energy strategies to meet Botswana’s Nationally Determined Contributions (NDCs) and enhance energy security by 2050, analysing six scenarios: Least Cost (LC), Business-As-Usual (BAU), Net Zero by 2050 (NZ), Coal Phase Out by 2045 (CPO), Fossil Fuel Phase Out by 2045 (FFPO), and Import Phase Out by 2045 (IMPPO). Our key findings highlight the critical role of solar technologies—photovoltaic (PV), storage, and concentrated solar power (CSP)—in transitioning to a sustainable energy future, especially under the Net Zero and Import Phase Out scenarios. This research demonstrates the economic and environmental benefits of transitioning away from fossil fuels, with the Fossil Fuel Phase Out scenario yielding a USD 31 million saving over the Business-As-Usual approach and reducing investment costs by USD 2 billion, albeit with a slight increase in light fuel oil imports. The study underscores the need for substantial capital investments, particularly in the Net Zero and Import Phase Out scenarios, necessitating private sector financing. Policy recommendations include adopting detailed strategies for solar PV and storage expansion, updating renewable energy targets, phasing out coal and natural gas, and bolstering the regulatory framework. These strategies are crucial for Botswana to achieve decarbonization and energy independence, aligning with global climate goals and national energy security objectives.
The Microstructures and Wear Resistance of CoCrFeNi2Mox High-Entropy Alloy Coatings
Authors: Liang Hui , Hou Jinxin , Liu Jianhong , Xu Hongtai , Li Yaning , Jiang Li , Cao Zhiqiang
Published: June 2024

The CoCrFeNi2Mox (x = 0, 0.4, 0.5, 1.0, x values in atomic ratio) high-entropy alloy coatings were designed and prepared on the Ti-6Al-4V substrate by laser cladding technology, their microstructures, and dry sliding wear resistance were studied in detail. When x < 0.4, the coatings were mainly composed of BCC solid solution phase, (Ni, Co)Ti2 phase, and α-Ti phase. When x ≥ 0.4, the new σ phase appeared in the coatings. As the Mo content increases from 0 to 1.0, the hardness showed a trend of first increasing and then decreasing, especially when x = 0.5, the coating hardness reached its maximum (882 HV), which was 2.65 times the hardness of the Ti-6Al-4V substrate. The CoCrFeNi2Mox high-entropy alloy coatings significantly improved the wear resistance of Ti-6Al-4V substrate, and with the increase in Mo content, the friction coefficient, widths/depths of worn tracks and wear rates of the coatings showed a trend of first decreasing and then increasing. In particular, when x = 0.5, the CoCrFeNi2Mo0.5 high-entropy alloy coating has the lowest friction coefficient (0.63), widths/depths of worn tracks (width: 803.690 μm; depth: 20.630 μm) and wear rate (5.136 × 10−5 mm3/(N·m)), which is one order of magnitude smaller than that of the substrate (3.694 × 10−4 mm3/(N·m)), demonstrating the best wear resistance. This is mainly because the appropriate proportion of hard α-Ti and σ phases effectively played a supporting role in resisting wear, while the relatively soft and dispersed BCC and (Ni, Co)Ti2 phases could effectively prevent the occurrence of brittle fracture during wear test process.
PbS Colloidal Quantum Dots: Ligand Exchange in Solution
Authors: Zhang Chuanxi , Han Dong , Zhang Xiaoyu
Published: June 2024

PbS colloidal quantum dots (CQDs) have the advantages of adjustable band gap, large exciton Bohr radius, controllable size, easy synthesis, and potential multi-exciton effect, making them attractive for photodetectors and solar cells. However, the long ligand chain wrapped on PbS CQDs limits carrier transport, and defect states of as-synthesized CQDs increase non-radiative recombination, negatively affecting photovoltaic performance. Surface properties determine the characteristics of CQDs, so ligand exchange processes are crucial. Because solution phase ligand exchange reduces labor and time requirements, it is more advantageous than solid phase ligand exchange. This review discusses the solution phase ligand exchange process of PbS CQDs, emphasizing the impact of surface ligands on conformation and conductivity.
Improving Trace Detection of Methylene Blue by Designing Nanowire Array on Boron-Doped Diamond as Electrochemical Electrode
Authors: He Sihan , Lin Kun , Cheng Shaoheng , Gao Nan , Liu Junsong , Li Hongdong
Published: June 2024

In this study, a boron-doped diamond nanowire array (BDD-NWA)-based electrode is prepared by using a microwave plasma chemical vapor deposition system and treated with inductively coupled plasma reactive ion etching. The BDD-NWA electrode is used for trace detection of methylene blue, which has a wide linear range of 0.04–10 μM and a low detection limit of 0.72 nM. Both the superhydrophilicity (contact angle ~0°) and the dense nanowire array’s structure after the etching process improve the sensitivity of the electrochemical detection compared to the pristine BDD. In addition, the electrode shows great repeatability (peak current fluctuation range of −3.3% to 2.9% for five detection/cleaning cycles) and stability (peak current fluctuation range of −5.3% to 6.3% after boiling) due to the unique properties of diamonds (mechanical and chemical stability). Moreover, the BDD-NWA electrode achieves satisfactory recoveries (93.8%–107.5%) and real-time monitoring in tap water.
Study on the Effects of GO on the Microstructure and Wear Resistance of CuCrZr Plasma Cladding Coatings
Authors: Wang Yang , Xiang Hongjun , Qiao Zhiming , Zhen Jianwei , Lv Qing-Ao , Yuan Xichao , Liang Chunyan , Cao Genrong
Published: June 2024

This study investigates the enhancement of wear resistance in CuCrZr rails through the plasma cladding of CuCrZr-GO coatings with a varying graphene oxide (GO) content. The microstructure, phase composition, and mechanical properties of CuCrZr coatings containing 0%, 0.2%, 0.4%, 0.6%, and 0.8% GO were examined using scanning electron microscopy (SEM), X-ray diffraction (XRD), ESD surface scanning, friction and wear tests, and hardness analysis. The findings indicated that increasing the GO content from 0% to 0.6% results in a transition in the coating microstructure from columnar to equiaxed crystals, leading to an improved density. However, at 0.8% GO, numerous porosity defects were observed. The coating containing 0.6% graphene oxide (GO) exhibited a superior performance, with a hardness of 75, a friction coefficient of approximately 0.7, and a wear mass of 2.84 mg under a 10 N load. In comparison to the CuCrZr coating lacking GO, the hardness showed an increase of around 4.8%, the friction coefficient decreased by approximately 5.1%, and the wear mass diminished by 59.4%. These findings hold significant implications for extending the operational lifespan of electromagnetic railguns.
A New Method for Determining Necking of Sheet Metal Based on Main Strain Topography
Authors: Shi Liqiu , Yang Yingjie , Hou Bo , Gu Weifang , Zhao Haitao , Feng Yan , Hang Zhouming
Published: June 2024

There are various methods to evaluate the forming limit of a sheet, and these criteria can be classified as position-dependent, time-dependent, and position-time dependent according to the basis of judgment. However, these criteria have a single function and can only find the forming limit of the sheet and cannot determine the strain distribution, strain change, or fracture location during the sheet forming process. This paper introduces a time–location-dependent method, i.e., the spatial strain rate method, which is used to detect the onset of necking of a sheet. The spatial strain rate is directly based on the strain and can not only find the forming limit of the sheet but also depict the strain distribution and strain variation during the two phases of the experimental process—distributed instability and concentrated instability—as well as predict the location of sheet fracture. The spatial strain rate of AA5083 aluminum alloy of different widths was analyzed and verified in detail via Nakazima experiments using digital image correlation techniques and compared with the guidelines published in the literature in recent years.
Large-Eddy Simulations of a Supersonic Impinging Jet Using OpenFOAM
Authors: You Rion Guang Yi , New Tze How , Chan Wai Lee
Published: June 2024

Supersonic impinging jets are a versatile configuration that can model the compressible flows of cold-spray manufacturing and vertical take-off-and landing strategy. In this work, rhoCentralFoam, solver of the OpenFOAM framework, and a large-eddy simulation formulation were used to simulate an underexpanded supersonic jet of Mach 1.45 and nozzle pressure ratio of 4, impinging on a flat wall situated at 1.5 nozzle diameters away from the jet outlet. Care was taken in the mesh construction to properly capture the characteristic standoff shock and vortical structures. The grid convergence index was evaluated with three meshes of increasing spatial resolution. All meshes can generally be considered as sufficient in terms of results focused on time-averaged values and mean physical properties such as centerline Mach number profile. However, the highest resolution mesh was found to capture fine shear vortical structures and behaviors that are absent in the coarser cases. Therefore, the notion of adequate grid convergence may differ between analyses of time-averaged and transient information, and so should be determined by the user’s intention for conducting the simulations. To guide the selection of mesh resolution, scaling analyses were performed, for which the current rhoCentralFoam solver displays a good weak scaling performance and maintains a linear strong scaling up to 4096 cores (32 nodes) for an approximately 40 million-cell mesh. Due to the internode communication bottlenecks of OpenFOAM and improvements in central processing units, this work recommends, for future scaling analyses, adopting a “cells-per-node” basis over the conventional “cells-per-core” basis, with particular attention to the interconnect speed and architecture used.
Syrga2: Post-Quantum Hash-Based Signature Scheme
Authors: Algazy Kunbolat , Sakan Kairat , Nyssanbayeva Saule , Lizunov Oleg
Published: June 2024

This paper proposes a new post-quantum signature scheme, Syrga2, based on hash functions. As known, existing post-quantum algorithms are classified based on their structures. The proposed Syrga2 scheme belongs to the class of multi-use signatures with state retention. A distinctive feature of state-retaining signatures is achieving a compromise between performance and signature size. This scheme enables the creation of a secure signature for r messages using a single pair of secret and public keys. The strength of signature algorithms based on hash functions depends on the properties of the hash function used in their structure. Additionally, for such algorithms, it is possible to specify the security level precisely. In the proposed scheme, the HBC-256 algorithm developed at the Institute of Information and Computational Technologies (IICT) is used as the hash function. The security of the HBC-256 algorithm has been thoroughly studied in other works by the authors. In contrast to the Syrga1 scheme presented in previous works by the authors, the Syrga2 scheme provides for the definition of different security levels determined by the parameter τ. This paper experimentally demonstrates the impossibility of breaking the proposed scheme using a chosen-plaintext attack. Additionally, the scheme’s performance is evaluated for signature creation, signing, and message verification.
Effects of CE Ferulic® Combined with Microneedling in the Treatment of Pigmentary Disorders: A Monocentric, Split Face, Comparative Study
Authors: Proietti Ilaria , Guida Stefania , Dybala Agnieszka , Spagnoli Alessandra , Potenza Concetta
Published: June 2024

Pigmentary disorders of the face present a significant challenge in dermatology, impacting the confidence and well-being of affected individuals. Various approaches have been developed to address these concerns, including microneedling and topical vitamin C products. This study involved 15 participants undergoing three treatment sessions over 12 weeks, assessing the efficacy of a combined microneedling and CE Ferulic® serum approach. Clinical evaluation and statistical analysis were conducted before and after the intervention. Significant improvement of akin hyperpigmentation was observed, particularly on the side treated with microneedling and CE Ferulic® serum compared to microneedling alone. The integrated treatment protocol demonstrated a synergistic effect in improving skin texture and appearance. Integrated treatment protocols, such as combining microneedling with CE Ferulic® serum, show promise in managing facial hyperpigmentation disorders. Further research with larger cohorts is warranted to validate these findings and optimize treatment strategies, highlighting the potential of combined therapeutic modalities for achieving optimal clinical outcomes in pigmentary disorder management.
High Mechanical Property and Texture Degree of Hot-Extruded Bi0.905Sb0.095
Authors: Zhao Linghao , Zhang Hongcheng , Zhao Degang , Wang Dawei , Liu Ruiheng , Feng Jianghe
Published: June 2024

Bi1−xSbx crystal is one of the best n-type thermoelectric materials below 200 K, but its weak mechanical strength hinders practical applications for deep refrigeration. Herein, we adopted the mechanical enhancement method of hot extrusion to investigate the comprehensive mechanical and thermoelectric properties of Bi0.905Sb0.095. It revealed that reducing the grain size of the matrix and increasing the extrusion ratio can improve the gain size uniformity and mechanical properties. Meanwhile, the thermoelectric performance depends on the texture, grain size, and local composition. The extruded sample prepared by ingot with the high extrusion ratio of 9:1 generated uniform small grains, which resulted in the high bending strength of Bi1−xSbx~130 Mpa and a high power factor of ~68 μW·cm−1·K−2@173 K, as well as the relatively high figure of merit of 0.25@173K. This work highlights the importance of the uniform distribution of the grain size and the compositions for Bi1−xSbx, as well as the required universal key parameter for the hot extrusion method.
Influence of Powder Size on Pore Characteristics and Intermetallic Phase Kinetics in Porous Ti-Al Alloys
Authors: Kayani Saif Haider , Ajmal Hafiz Muhammad Salman , Kim Byung-Joo , Park Nho-Kwang , Euh Kwangjun
Published: June 2024

This study investigates the impact of varying powder size on porosity, pore parameters, and intermetallic phase reaction during the reactive sintering of porous TiAl alloys. Ti52Al48 alloys were prepared using coarse (200 mesh) and fine (325 mesh) Ti powders through elemental powder metallurgy and were subsequently sintered at different temperatures, 600 and 1200 °C. Our findings reveal a consistent pore morphology and intermetallic phase microstructure across both alloys. However, samples containing fine Ti powder exhibited a higher number density of small pores compared to those incorporating coarse Ti powders. Additionally, alloys prepared with fine Ti powders demonstrated a higher porosity than those prepared with coarse powders. Consequently, fine Ti powder promoted enhanced diffusion between Ti and Al during sintering, as reflected by the lower onset temperature and enthalpy of intermetallic reaction during sintering.
Conservation Prioritization of Orthoptera Assemblages on a Mediterranean Island
Authors: Tzirkalli Elli , Zografou Konstantina , Willemse Luc , Vogiatzakis Ioannis N. , Kati Vassiliki
Published: June 2024

In response to the ongoing global extinction, conservationists must prioritize future conservation investments to ensure that such measures are biologically effective and economically viable. To propose an effective conservation plan for Orthoptera assemblages on Cyprus Island, we introduce the Standardized Conservation Index (StCI), a biodiversity index accounting for the conservation value (ci), presence, dispersal ability, endemism and conservation status of a species. We evaluated the effect of eleven environmental variables on StCI, ci, species richness and the Shannon–Wiener diversity index, using linear and generalized linear models. Species and environmental data were collected in 60 localities that were placed along four elevational zones and included seven habitat types. Our results revealed the importance of rural mosaics and forests for the conservation of Orthoptera. The Shannon–Wiener diversity index failed to show the importance of high-altitude forests. The Orthoptera species diversity was favored by flower heads and the soil humidity, while rock cover and high shrubs had a positive and negative effect, respectively, on the StCI and ci values. Our results underline the value of StCI in complementing traditional diversity indices, as a scale-independent index that can be used for different taxa to prioritize sites of conservation concern.
Leaf Architecture in the Morphological Diversity of the Genus Prosopis in the Semi-Desert Area of Northeastern Mexico
Authors: Foroughbakhch Pournavab Rahim , Ngangyo Heya Maginot , Castillo Gonzalez Emmanuel Adan , Rocha Estrada Alejandra , Salas Cruz Lidia Rosaura , Alvarado Vázquez Marco Antonio
Published: June 2024

Mesquite (Prosopis spp.) is one of the main plant representatives in regions with a dry climate, and is a fundamental part of the flora of the Mexican arid, with an indisputable importance from ecological, economic and industrial points of view. However, the restrictive factors of dry climates, as well as genetic variability, are sources of the great diversity of mesquite, so its taxonomy is not yet well defined. The present study seeks to determine the diversity of mesquite in the Mexican semi-desert based on the morphometric characterization of its leaves. Methods: Different leaf parameters such as the number, length and width of the leaflets were recorded in 31 well-marked sites in the area, to obtain measures of central tendency and dispersion, and to determine the differences and similarities between the sites, as well as the groups of homogeneous and heterogeneous taxa. Results: Five taxa were identified, of which there were two varieties (Prosopis glandulosa var. glandulosa and Prosopis reptans var. cinerascens), a pure or typical species (Prosopis laevigata) and two hybrids (Prosopis glandulosa var. glandulosa x Prosopis laevigata and Prosopis laevigata x Prosopis glandulosa var. glandulosa). The discriminant analysis indicated that five variables presented the highest percentage of separation or best separated the taxa, so the study was based on the phenogram with the combination of these five variables: (a) length of middle leaflets, (b) length of upper leaflets, (c) spacing of middle leaflets, (d) length/width relationship of middle leaflets and (e) length/width relationship of middle leaflets. Conclusions: Both the traditional taxonomic classification and the cluster and discriminant analyses reflected the same taxa (Prosopis glandulosa var. glandulosa, Prosopis laevigata and Prosopis reptans var. cinerascens) and the existence of hybridization between Prosopis glandulosa var. glandulosa and Prosopis laevigata.
Design and Application of Low-Temperature Geothermal Thermoelectric Power Generation (Lotemg–TPG) in Sari Ater Hot Spring, Ciater, Subang, West Java, Indonesia
Authors: Marpaung Harapan , Supriyadi  , Lasmi Ni Ketut , Singarimbun Alamta , Srigutomo Wahyu
Published: June 2024

The use of surface geothermal manifestations in Indonesia is still very limited as a tourist attraction. Solid-state thermoelectric generator technology is an alternative to converting electrical energy directly from a heat source in the form of low-temperature geothermal manifestation. Low-temperature geothermal thermoelectric power generation (Lotemg–TPG) was designed, manufactured, and tested to take advantage of this opportunity. It was also applied to the Sari Ater Hot Spring, Ciater. The Lotemg–TPG unit comprises seven M8T modules in two frame blocks equipped with hot- and cold-water circulation channels. The M8T module is the main part of the Lotemg–TPG, which consists of eight TEG elements of type TEG1-241-1.4-1.2, flanked by a hot-side radiator and a cold-side radiator. The measurement results showed that at the temperature difference between the hot-side Th and the cold-side Tc of ∆T 17.38 °C, one module can produce 1.30 W of power, so the total power of the Lotemg–TPG unit is around 9.10 W. This result is quite good considering that the heat source is obtained for free, and the device can operate to produce stable electrical power.