bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on Energy Efficiency Optimization of Visible Light Communication Based on Non-Orthogonal Multiple Access
Authors: Wu Yali , Sun Lei , Liu Xiaoshuang , Lin Xiaoran
Published: April 2024

As a contender in the competitive landscape of next-generation wireless communication technologies, visible light communication (VLC) stands out due to its potential for enhancing transmission rates and spectrum resource utilization. VLC offers various advantages, including license-free operation, high confidentiality, and cost-effectiveness. However, practical implementation faces challenges stemming from the limited modulation bandwidth of light-emitting diodes (LEDs), constraining system capacity and VLC communication rates. To address this limitation, non-orthogonal multiple access (NOMA) emerges as a novel multiple access strategy, particularly suitable for enhancing the capacity and communication rates of downlink VLC systems through power multiplexing. This paper delves into the energy-efficient design of joint LED association and power allocation (LA–PA) for downlink NOMA-based VLC systems. Through an analysis of channel capacity, we transform the non-convex energy-efficient optimization model, accounting for signal non-negativity, per-LED optical power constraints, and user rate constraints, into a convex form. Subsequently, we propose an iterative power allocation algorithm to attain solutions for the optimization problem with pre-established LED associations. Furthermore, we derive a feasibility condition for an LED association, considering signal non-negativity, per-LED optical power constraints, power constraints for successive interference cancellation (SIC), and channel gain between transceiver signals. This condition identifies feasible LEDs capable of maximizing energy efficiency (EE) when combined with the aforementioned power allocation algorithm. Finally, we illustrate the superiority of the joint LA–PA scheme in terms of the EE, transmission reliability, and transmission capacity performance gain over NOMA in the context of VLC.
Energy Management in a Super-Tanker Powered by Solar, Wind, Hydrogen and Boil-Off Gas for Saving CO2 Emissions
Authors: Stamatakis Michael E. , Stamataki Erofili E. , Stamelos Anastasios P. , Ioannides Maria G.
Published: April 2024

In terms of energy generation and consumption, ships are autonomous isolated systems, with power demands varying according to the type of ship: passenger or commercial. The power supply in modern ships is based on thermal engines-generators, which use fossil fuels, marine diesel oil (MDO) and liquefied natural gas (LNG). The continuous operation of thermal engines on ships during cruises results in increased emissions of polluting gases, mainly CO/CO2. The combination of renewable energy sources (REs) and triple-fuel diesel engines (TFDEs) can reduce CO/CO2 emissions, resulting in a “greener” interaction between ships and the ecosystem. This work presents a new control method for balancing the power generation and the load demands of a ship equipped with TFDEs, fuel cells (FCs), and REs, based on a real and accurate model of a super-tanker and simulation of its operation in real cruise conditions. The new TFDE technology engines are capable of using different fuels (marine diesel oil, heavy fuel oil and liquified natural gas), producing the power required for ship operation, as well as using compositions of other fuels based on diesel, aiming to reduce the polluting gases produced. The energy management system (EMS) of a ship is designed and implemented in the structure of a finite state machine (FSM), using the logical design of transitions from state to state. The results demonstrate that further reductions in fossil fuel consumption as well as CO2 emissions are possible if ship power generation is combined with FC units that consume hydrogen as fuel. The hydrogen is produced locally on the ship through electrolysis using the electric power generated by the on-board renewable energy sources (REs) using photovoltaic systems (PVs) and wind energy conversion turbines (WECs).
A Social Perspective on AI in the Higher Education System: A Semisystematic Literature Review
Authors: Alshahrani Budur Turki , Pileggi Salvatore Flavio , Karimi Faezeh
Published: April 2024

The application of Artificial Intelligence in Education (AIED) is experiencing widespread interest among students, educators, researchers, and policymakers. AIED is expected, among other things, to enhance learning environments in the higher education system. However, in line with the general trends, there are also increasing concerns about possible negative and collateral effects. The consequent social impact cannot be currently assessed in depth. Balancing benefits with social considerations according to a socio-technical approach is essential for harnessing the true power of AI in a responsible and trustworthy context. This study proposes a semi-systematic literature review of the available knowledge on the adoption of artificial intelligence (AI) in the higher education system. It presents a stakeholder-centric analysis to explore multiple perspectives, including pedagogical, managerial, technological, governmental, external, and social ones. The main goal is to identify and discuss major gaps and challenges in context, looking at the existing body of knowledge and momentum. AIED should encompass pedagogical, ethical, and social dimensions to be properly addressed. This review highlights a not-always-explicit socio-technical perspective. Additionally, this study reveals a significant lack of empirical systematic evaluation of added value and institutional readiness. Because of the broad scope of the study and the intense ongoing debate on the topic, an exhaustive identification of the current body of knowledge is probably unrealistic, so this study aims mainly to identify the mainstream and major trends by looking at the most recent contributions.
Comparison of Non-Covalent and Covalent Interactions between Lactoferrin and Chlorogenic Acid
Authors: Li Zekun , Al-Wraikat Majida , Hao Changchun , Liu Yongfeng
Published: April 2024

Adding polyphenols to improve the absorption of functional proteins has become a hot topic. Chlorogenic acid is a natural plant polyphenol with anti-inflammatory, antioxidant, and anticancer properties. Bovine lactoferrin is known for its immunomodulatory, anticancer, antibacterial, and iron-chelating properties. Therefore, the non-covalent binding of chlorogenic acid (CA) and bovine lactoferrin (BLF) with different concentrations under neutral conditions was studied. CA was grafted onto lactoferrin molecules by laccase catalysis, free radical grafting, and alkali treatment. The formation mechanism of non-covalent and covalent complexes of CA-BLF was analyzed by experimental test and theoretical prediction. Compared with the control BLF, the secondary structure of BLF in the non-covalent complex was rearranged and unfolded to provide more active sites, the tertiary structure of the covalent conjugate was changed, and the amino group of the protein participated in the covalent reaction. After adding CA, the covalent conjugates have better functional activity. These lactoferrin–polyphenol couplings can carry various bioactive compounds to create milk-based delivery systems for encapsulation.
Preparation of Resistant Starch Types III + V with Moderate Amylopullulanase and Its Effects on Bread Properties
Authors: Li Jianglong , Deng Faxiang , Han Peng , Ding Yangyue , Cao Jianxin
Published: April 2024

The potential of PulY103A (a moderate amylopullulanase originating from Bacillus megaterium) for resistant starch production under moderate conditions (40 °C; a pH of 6.5) was investigated. PulY103A was much more suitable for pea resistant starch production with a high growth rate of 3.63. The pea resistant starch (PSpa) produced with PulY103A had lower levels of swelling power and solubility and a better level of thermostability than native pea starch (PSn) and autoclaved PS (PSa). The starch crystallinity pattern was B + V, which indicated that the PSpa belonged to RS types III + V. In addition, PSpa was used for breadmaking. The results showed that the bread quality was not significantly influenced compared to the control group when the content of PSpa was under 10% (p > 0.05). The bread supplemented with 10% PSpa had a significantly increased TDF content compared to that of the control (p < 0.05). Moreover, the in vitro mineral bioavailability of the bread sample was influenced gently compared to other dietary fibers, and the bread sample changed from a high-glycemic-index (GI) food to a medium-GI food corresponding to white bread at the same concentration of PSpa. These results indicated that PSpa is a good candidate for the production of dietary foods.
Love in the Mother Tongue: Per Fokstad’s Philosophy of Education
Authors: Svendsen Stine H. Bang
Published: April 2024

In the first decades of the 20th century, the Sámi movement developed a vision for how education could play a central role in the future of the Sámi people. Faced with expanding colonial school systems, teachers and intellectuals imagined what education could look like if it was to contribute to the flourishing of Sámi livelihoods. One key contributor to this project was Per Pavelsen Fokstad (1890–1973). This article outlines key elements in Fokstad’s philosophy of education and discusses his contribution to education theory in both his contemporary cultural interface and the one that we work in over 100 years later. The analyses are based on a hermeneutical reading of Fokstad’s published texts. The analyses show how Fokstad outlined a philosophy of education based in the mother tongue as a catalyst for the child’s development of a sense of self, a feeling of community, and a connection to land. This philosophy was revolutionary in his own time due to its redefinition of what was worth learning and knowing, and has grown in significance since.
An Inversion Method for Surrounding Rock Parameters of Tunnels Based on a Probabilistic Baseline Model under a Constructional Environment
Authors: Shi Chenpeng , Yan Xiaokun , Yang Jianxing , Liu Yang
Published: April 2024

The uncertainty of surrounding rock parameters varies due to changes in the boundary conditions of the tunnel model, and no suitable method to ensure that the updated parameters of the finite element model (FEM) are applicable throughout the constructional environment. To address this issue, a probabilistic baseline model method was introduced to invert the rock parameters and obtain values suitable for the complete constructional environment. First, the probabilistic statistical theory was applied to statistically analyze the measurement data from tunnels under different constructional environments, which provides insight into the variation in rock parameters. Then, an objective optimization function based on a genetic algorithm (GA) was constructed to optimize the accuracy by minimizing the error between the measurement data and the simulation data. Next, a Kriging model was built that utilized Young’s modulus and cohesion as updated parameters. This approach contributes to overcoming the inefficiency of multi-objective optimization computations. By using the Kriging model, optimal values for the rock parameters were obtained. Finally, the effectiveness and applicability of the proposed method were validated by comparing the measured data with the updated model data under different constructional environments.
Fundamental Themes in Social–Emotional Learning: A Theoretical Framework for Inclusivity
Authors: Dussault Mickayla , Thompson Robert B.
Published: April 2024

Social–emotional learning (SEL) is a rapidly growing field of research that has garnered significant attention in recent years. Each facet of SEL research in fields such as education, mental health, and developmental research has used specific methodologies and terms in their narrow research focus. In education specifically, where the most SEL research has been produced, many frameworks have implementation requirements. The lack of a framework focused on overarching themes without implementation requirements prevents the fields from coming together to compile and compare research and progress to create parent-, adult-, or mental health-specific SEL programs. This paper provides a conceptual analysis of SEL, aimed at clarifying the concept and deconstructing its various facets. This framework is needed to acknowledge the many different terms and skills for the same principle while also narrowing down definitions for clarity. The resulting framework can be used as a basis for future research, practice, and policy discussions in the field.
Exploring Allied Health Models of Care for Children with Developmental Health Concerns, Delays, and Disabilities in Rural and Remote Areas: A Systematic Scoping Review
Authors: Gosse Georgia , Kumar Saravana , Banwell Helen , Moran Anna
Published: April 2024

Background: Access to appropriate healthcare is essential for children’s healthy development. This is lacking in rural and remote areas, impacting health outcomes. Despite efforts to improve access for these communities, to date, no review has systematically mapped the literature on allied health models of care for children with developmental needs. This scoping review seeks to address this knowledge gap. Methods: Adhering to the PRISMA-ScR and Joanna Briggs Institute guidelines, a systematic search was conducted. A total of 8 databases (from inception to May 2023) and 106 grey literature sources were searched. Two reviewers independently undertook a two-stage screening process. Data were extracted using customised tools and narratively synthesised utilising the Institute of Medicine’s quality domains. This review is registered a priori via Open Science Framework. Results: Twenty-five citations were identified within the literature. Varied models of care were reported from five mostly Western countries. Models of care identified in these areas were classified as screening services, role substitution, consultative services, or online-based services. Positive impacts on quality of healthcare were reported across all quality domains (apart from safety) with the domain of effectiveness being the most commonly reported. Conclusions: Multiple models of care are currently in operation for children with developmental needs in rural and remote areas and appear to improve the quality of care. Due to complexities within, and limitations of, the evidence base, it is unclear if one model of care is superior to another. This review provides a basis for further research to explore why some models may be more effective than others.
Cognitive and Relational Processes Associated to Mental Health in Italian High School Students during COVID-19 and Russian–Ukrainian War Outbreaks
Authors: Negri Attà , Barazzetti Arianna , Rinzivillo Alice , Mariani Rachele , Di Monte Cinzia
Published: April 2024

The negative impact of the COVID-19 pandemic on mental health has been widely demonstrated; however, few studies have investigated the psychological processes involved in this impact, including core beliefs violation, meaning-making disruption, interpersonal support, or one’s relational functioning. This study explored the mental health of 215 Italian adolescents during the COVID-19 pandemic and the subsequent outbreak of the Russian–Ukrainian war. By administering a set of questionnaires, several cognitive and emotional variables were investigated, including core belief violation, meaning attribution to the pandemic and war, attachment, and emotion regulation, social media addiction, and relationships with significant others and teachers. We conducted some descriptive, mean difference, correlational, and predictive analyses that revealed a significant association between core belief violation caused by war and pandemic, ability to integrate war and pandemic within personal meaning universe, the relational support received, and mental health. The relationship with teachers during these challenging periods improved significantly according to the respondents’ opinion, becoming both more authoritative and empathic. This study offers insights into what cognitive and relational processes are useful to intervene on to reduce the distress of adolescents who are facing significant moments of crisis due to events that challenge their cognitive and emotional balance.
Patterns of Chromosomal Instability and Clonal Heterogeneity in Luminal B Breast Cancer: A Pilot Study
Authors: Camargo-Herrera Valentina , Castellanos Giovanny , Rangel Nelson , Jiménez-Tobón Guillermo Antonio , Martínez-Agüero María , Rondón-Lagos Milena
Published: April 2024

Chromosomal instability (CIN), defined by variations in the number or structure of chromosomes from cell to cell, is recognized as a distinctive characteristic of cancer associated with the ability of tumors to adapt to challenging environments. CIN has been recognized as a source of genetic variation that leads to clonal heterogeneity (CH). Recent findings suggest a potential association between CIN and CH with the prognosis of BC patients, particularly in tumors expressing the epidermal growth factor receptor 2 (HER2+). In fact, information on the role of CIN in other BC subtypes, including luminal B BC, is limited. Additionally, it remains unknown whether CIN in luminal B BC tumors, above a specific threshold, could have a detrimental effect on the growth of human tumors or whether low or intermediate CIN levels could be linked to a more favorable BC patient prognosis when contrasted with elevated levels. Clarifying these relationships could have a substantial impact on risk stratification and the development of future therapeutic strategies aimed at targeting CIN in BC. This study aimed to assess CIN and CH in tumor tissue samples from ten patients with luminal B BC and compare them with established clinicopathological parameters. The results of this study reveal that luminal B BC patients exhibit intermediate CIN and stable aneuploidy, both of which correlate with lymphovascular invasion. Our results also provide valuable preliminary data that could contribute to the understanding of the implications of CIN and CH in risk stratification and the development of future therapeutic strategies in BC.
A Step Forward for the Treatment of Localized Prostate Cancer Using Gold Nanoparticles Combined with Laser Irradiation
Authors: Pinho Sara , Ferreira-Gonçalves Tânia , Lopes Joana , Amaral Mariana Neves , Viana Ana S. , Coelho João M. P. , Gaspar Maria Manuela , Reis Catarina Pinto
Published: April 2024

Prostate cancer (PCA) is the second most common cancer diagnosis in men and the fifth leading cause of death worldwide. The conventional treatments available are beneficial to only a few patients and, in those, some present adverse side effects that eventually affect the quality of life of most patients. Thus, there is an urgent need for effective, less invasive and targeted specific treatments for PCA. Photothermal therapy (PTT) is a minimally invasive therapy that provides a localized effect for tumour cell ablation by activating photothermal agents (PTA) that mediate the conversion of the light beam’s energy into heat at the site. As tumours are unable to easily dissipate heat, they become more susceptible to temperature increases. In the PTT field, gold nanoparticles (AuNPs) have been attracting interest as PTA. The aim of this study was to formulate AuNPs capable of remaining retained in the tumour and subsequently generating heat at the tumour site. AuNPs were synthesized and characterized in terms of size, polydispersity index (PdI), zeta potential (ZP), morphology and the surface plasmon resonance (SPR). The safety of AuNPs and their efficacy were assessed using in vitro models. A preliminary in vivo safety assessment of AuNPs with a mean size lower than 200 nm was confirmed. The morphology was spherical-like and the SPR band showed good absorbance at the laser wavelength. Without laser, AuNPs proved to be safe both in vitro (>70% viability) and in vivo. In addition, with laser irradiation, they proved to be relatively effective in PCA cells. Overall, the formulation appears to be promising for use in PTT.
On Connective Tissue Mast Cells as Protectors of Life, Reproduction, and Progeny
Authors: Norrby Klas
Published: April 2024

The connective tissue mast cell (MC), a sentinel tissue-residing secretory immune cell, has been preserved in all vertebrate classes since approximately 500 million years. No physiological role of the MC has yet been established. Considering the power of natural selection of cells during evolution, it is likely that the MCs exert essential yet unidentified life-promoting actions. All vertebrates feature a circulatory system, and the MCs interact readily with the vasculature. It is notable that embryonic MC progenitors are generated from endothelial cells. The MC hosts many surface receptors, enabling its activation via a vast variety of potentially harmful exogenous and endogenous molecules and via reproductive hormones in the female sex organs. Activated MCs release a unique composition of preformed and newly synthesized bioactive molecules, like heparin, histamine, serotonin, proteolytic enzymes, cytokines, chemokines, and growth factors. MCs play important roles in immune responses, tissue remodeling, cell proliferation, angiogenesis, inflammation, wound healing, tissue homeostasis, health, and reproduction. As recently suggested, MCs enable perpetuation of the vertebrates because of key effects—spanning generations—in ovulation and pregnancy, as in life-preserving activities in inflammation and wound healing from birth till reproductive age, thus creating a permanent life-sustaining loop. Here, we present recent advances that further indicate that the MC is a specific life-supporting and progeny-safeguarding cell.
Exploiting Properties of Student Networks to Enhance Learning in Distance Education
Authors: Tsoni Rozita , Paxinou Evgenia , Gkoulalas-Divanis Aris , Karapiperis Dimitrios , Kalles Dimitrios , Verykios Vassilios S.
Published: April 2024

Distance Learning has become the “new normal”, especially during the pandemic and due to the technological advances that are incorporated into the teaching procedure. At the same time, the augmented use of the internet has blurred the borders between distance and conventional learning. Students interact mainly through LMSs, leaving their digital traces that can be leveraged to improve the educational process. New knowledge derived from the analysis of digital data could assist educational stakeholders in instructional design and decision making regarding the level and type of intervention that would benefit learners. This work aims to propose an analysis model that can capture the students’ behaviors in a distance learning course delivered fully online, based on the clickstream data associated with the discussion forum, and additionally to suggest interpretable patterns that will support education administrators and tutors in the decision-making process. To achieve our goal, we use Social Network Analysis as networks represent complex interactions in a meaningful and easily interpretable way. Moreover, simple or complex network metrics are becoming available to provide valuable insights into the students’ social interaction. This study concludes that by leveraging the imprint of these actions in an LMS and using metrics of Social Network Analysis, differences can be spotted in the communicational patterns that go beyond simple participation recording. Although HITS and PageRank algorithms were created with completely different targeting, it is shown that they can also reveal methodological features in students’ communicational approach.
Nitroprusside Combined with Leg Raise at the Time of Right Heart Catheterization to Differentiate Precapillary from Other Hemodynamic Forms of Pulmonary Hypertension: A Single-Center Pilot Study
Authors: Naguib Mostafa , Aljwaid Ahmed , Marella Dean , Flores Raul J. , Singh Abhishek
Published: April 2024

Pulmonary hypertension (PH) can arise from several distinct disease processes, with a percentage presenting with combined pre- and postcapillary pulmonary hypertension (cpcPH). Patients with cpcPH are unsuitable candidates for PH-directed therapies due to elevated pulmonary capillary wedge pressures (PCWPs); however, the PCWP is dynamic and is affected by both preload and afterload. Many patients that are diagnosed with cpcPH are hypertensive at the time of right heart catheterization which has the potential to increase the PCWP and, therefore, mimic a more postcapillary-predominant phenotype. In this small pilot study, we examine the effect of nitroprusside combined with dynamic preload augmentation with a passive leg raise maneuver in hypertensive cpcPH patients at the time of right heart catheterization to identify a more precapillary-dominant PH phenotype. Patients that met the criteria of PCWP ≤ 15 mmHg with nitroprusside infusion and PCWP ≤ 18 mmHg with nitroprusside infusion and simultaneous leg raise were started on pulmonary vascular-targeted therapy. Long-term PH therapy was well tolerated, with increased six-minute walk distance, improved WHO functional class, decreased NT-proBNP, and improved REVEAL 2.0 Lite Risk Score in this precapillary-dominant PH phenotype. This small study highlights the importance of characterizing patient physiology beyond resting conditions at the time of right heart catheterization.
Topographic Keratoconus Incidence in Greece Diagnosed in Routine Consecutive Cataract Procedures: A Consecutive Case Series of 1250 Cases over 5 Years
Authors: Kanellopoulos Anastasios John , Kanellopoulos Alexander J.
Published: April 2024

Background: Scheimpflug tomography has for many years been an integral part of our pre-operative assessment in cataract extraction. We retrospectively reviewed the incidence of topographic keratoconus and keratoconus suspicion in our routine cataract surgery population over 5 years. Setting: The Laservision Clinical and Research Institute, Athens, Greece. Methods: In 1250 consecutive cataract surgery cases in otherwise naïve eyes, accounting for years 2017 to 2021, we retrospectively evaluated preoperative Pentacam HR imaging. The cases already classified as keratoconus were included in group A. The residual cases were assessed by five different experienced evaluators (two ophthalmic surgeons and three optometrists) for topographic and tomographic keratoconus suspicion based on irregular pachymetry distribution, astigmatism truncation, and/or astigmatic imaging irregularity and included in group B. Regular corneas, by this assessment, were included in group C; irregular corneas, as determined by the evaluators but unrelated to keratoconus, were included in group D. Results: Based on the above, 138 cases (11.08%) were classified by Pentacam tomography as keratoconus and by default were included in group A. Of the residual cases, 314 or 25.12% were classified as suspect keratoconus and included in group B; 725 cases (58%) were classified as normal and non-keratoconus and included in group C; and 73 cases or 5.84% were placed in group D as non-keratoconus but abnormal. There was no disagreement between the five evaluators over any of the cases in groups C and D, and little variance among them for cases included in group B (less than 5% by ANOVA). Conclusions: The incidence of keratoconus and corneas suspicious for keratoconus in Greece appears to be much higher than respective reports from other regions: one in ten Greeks appear to have topographic keratoconus, most not diagnosed even by the age of cataract surgery, and almost an additional one in four may have suspicious corneal imaging for keratoconus. These data strongly imply that routine screening for disease should be promoted among Greeks, especially during puberty, to halt possible progression; moreover, careful screening should be performed when laser vision correction is being considered.
Linezolid-Associated Thrombocytopenia: Assessment of Risk Factors in Patients without Hemato-Oncologic Diseases
Authors: Thabit Abrar K. , Alghamdi Arwa A. , Alsaeed Afnan K. , Magbool Nesereen M. , Alsowaida Yazed S. , Mahrous Ahmad J. , Alruwaili Alya , Albakistani Ziyad K. , Albangali Basem O. , Alghumuy Anas M. , Youssef Sara A. , Alodayli Reem M. , Almutairi Masaad Saeed
Published: April 2024

Background: Linezolid is used for Gram-positive bacterial infections. Thrombocytopenia is one of its main adverse effects resulting from myelosuppression. Several studies have assessed risk factors that may increase the risk of this adverse effect. However, most studies included patients with hemato-oncologic diseases, which may confound such assessments. This study aimed to investigate risk factors for linezolid-associated thrombocytopenia in patients without hemato-oncologic diseases. Methods: This was a multicenter retrospective case-control study of adult patients treated with linezolid twice daily for ≥3 days. Patients with hemato-oncologic diseases, active dengue fever, active COVID-19, baseline platelet count <100 × 103/mm3, concurrent therapy with trimethoprim/sulfamethoxazole or valproic acid, and a recent platelet transfusion within 7 days were excluded. Thrombocytopenia was defined as a drop in platelet count below 100 × 103/mm3. Results: Out of 158 evaluated patients, 33 developed thrombocytopenia, indicating an incidence rate of 20.9%. Of all the risk factors assessed, creatinine clearance of <60 mL/min and bacteremia/infective endocarditis were significantly associated with linezolid-associated thrombocytopenia (adjusted odds ratios, 3.25 and 5.95; 95% CI 1.12–9.45 and 1.23–28.66; p = 0.031 and 0.026, respectively). End of therapy platelet counts were significantly lower in the cases than in the controls (79 vs. 243 × 103/mm3; p < 0.001). Similarly, the percentage of platelet count change was significantly different (−55.1% vs. −10.2%; p < 0.001). Conclusions: In our study, the incidence rate of linezolid-associated thrombocytopenia was 20.9%, and we found that patients with renal impairment and bacteremia may need close monitoring of platelet counts. Prospective studies are warranted to evaluate the potential need for renal dose adjustment.
Immunomodulatory Effect of COVID-19 on HLA-Antibody Profile in Renal Transplant Recipients
Authors: Kljajic Marina , Sabljic Zoran , Juric Ivana , Furic Cunko Vesna , Zunec Renata , Burek Kamenaric Marija , Jelakovic Bojan , Basic-Jukic Nikolina
Published: April 2024

Background/Objectives: The novel coronavirus disease 2019 (COVID-19) has led to significant morbidity and mortality among kidney transplant recipients. SARS-CoV-2 has been hypothesized to cause an unusual immunological dysregulation triggering alloimmunity and leading to graft rejection. Methods: This prospective observational cohort study assessed 321 kidney transplant recipients who had COVID-19 infection. After the infection, patients’ sera were tested for the presence of anti-HLA de novo DSA and non-DSA specificities. Logistic regression analysis and a stepwise multivariable logistic regression analysis were used to analyze the independent risk factors associated with the development of antibodies, adjusting for known confounders. The variables evaluated were acute COVID-19 characteristics (i.e., presentation, and need for hospitalization), demographic characteristics (i.e., age, gender, and primary renal disease), clinical characteristics (i.e., various comorbidities), and post-COVID-19 sequelae. Results: Anti-HLA de novo DSA developed in 18.7% of patients, while anti-HLA class I and class II non-DSA antibodies developed de novo in 84 (26.3%) and 83 (25.9%) patients, respectively. The development of DSA, HLA-DQ, and HLA-DR antibodies was predicted by the history of graft rejection. Obesity appeared to be protective against the emergence of de novo DSA. De novo DSA and HLA-DR antibody formation was positively linked with intravenous immunoglobulin use, CMV-hyperimmune globulin use, and decreased doses of immunosuppression during acute infection. Better allograft function during the acute disease was a protective factor against the formation of HLA-DQ and HLA-DR antibodies. Positive predictors of de novo DSA development were graft biopsy and the reactivation of EBV after infection. Conclusions: These findings suggest that the SARS-CoV-2 virus has an immunomodulatory effect and may be associated with an increased mortality in this population.
Catheter Ablation for Channelopathies: When Is Less More?
Authors: Mehta Adhya , Chandiramani Rishi , Ghosh Binita , Asatryan Babken , Hajra Adrija , Barth Andreas S.
Published: April 2024

Ventricular fibrillation (VF) is a common cause of sudden cardiac death in patients with channelopathies, particularly in the young population. Although pharmacological treatment, cardiac sympathectomy, and implantable cardioverter defibrillators (ICD) have been the mainstay in the management of VF in patients with channelopathies, they are associated with significant adverse effects and complications, leading to poor quality of life. Given these drawbacks, catheter ablation has been proposed as a therapeutic option for patients with channelopathies. Advances in imaging techniques and modern mapping technologies have enabled increased precision in identifying arrhythmia triggers and substrate modification. This has aided our understanding of the underlying pathophysiology of ventricular arrhythmias in channelopathies, highlighting the roles of the Purkinje network and the epicardial right ventricular outflow tract in arrhythmogenesis. This review explores the role of catheter ablation in managing the most common channelopathies (Brugada syndrome, congenital long QT syndrome, short QT syndrome, and catecholaminergic polymorphic ventricular tachycardia). While the initial results for ablation in Brugada syndrome are promising, the long-term efficacy and durability of ablation in different channelopathies require further investigation. Given the genetic and phenotypic heterogeneity of channelopathies, future studies are needed to show whether catheter ablation in patients with channelopathies is associated with a reduction in VF, and psychological distress stemming from recurrent ICD shocks, particularly relative to other available therapeutic options (e.g., quinidine in high-risk Brugada patients).
The Association of Desert Dust with the Risk of Acute Coronary Syndrome in Subjects of a Younger Age
Authors: Domínguez-Rodríguez Alberto , Baéz-Ferrer Néstor , Avanzas Pablo , Rodríguez Sergio , Abreu-González Pedro , Trujillo-Martin Elisa , Burillo-Putze Guillermo , Hernández-Vaquero Daniel
Published: April 2024

Objectives: Recently, desert dust in Europe has been recognized as a cardiovascular health problem. In Spain, desert dust inflows in recent years have been associated with worsening air quality. The present study examines whether desert dust events are related to the incidence of acute coronary syndrome (ACS) in patients under 55 years of age. Methods: Data from 2416 consecutive patients admitted to a tertiary hospital due to ACS were prospectively analyzed. A case-crossover time-stratified design using Poisson conditional regression models was applied to estimate the impact of desert dust events involving particulate matter concentrations of an aerodynamic diameter <10 μm (PM10) on the incidence of ACS in patients under 55 years of age. Results: Desert dust intrusion on days 0 to 5 before ACS onset showed no significant association with the incidence of ACS in patients under 55 years of age. The incidence rate ratios of PM10 concentrations 1, 2, 3, 3, 4, and 5 days before ACS onset (for changes of 10 µg/m3) were 1.02 (95% CI 0.97–1.1; p = 0.41), 1.01 (95% CI 0.96–1.07; p = 0.66), 0.99 (95% CI 0.94–1.05; p = 0.78), 0.96 (95% CI 0.9–1.02; p = 0.18), and 0.97 (95% CI 0.91–1.04; p = 0.41). Conclusions: Our findings suggest that desert dust is unlikely to be related to the incidence of ACS in patients under 55 years of age.
Intraoperative Fracture during the Insertion of Advanced Locking Screws (T2 Alpha Femur Retrograde Intramedullary Nailing System): Report of Two Cases and Identifying Causes and Prevention
Authors: Higuchi Takashi , Taninaka Atsushi , Yoshimizu Rikuto , Hayashi Katsuhiro , Miwa Shinji , Yamamoto Norio , Tsuchiya Hiroyuki , Demura Satoru
Published: April 2024

Background: Recently, the T2 alpha nailing system (Stryker, Inc.), which has advanced locking screws that can attach a screw to a rod, has been used worldwide and is expected to improve fracture fixation. We analyzed two cases of supracondylar femoral fractures in older adult patients, in which intraoperative fractures occurred during the insertion of advanced locking screws of the T2 alpha femur retrograde intramedullary nail. Case presentation: A 93-year-old and an 82-year-old woman each underwent T2 alpha femur retrograde nail fixation for supracondylar femur fractures at separate hospitals, and advanced locking screws were used as the proximal transverse locking screws. In both patients, a fracture line was observed at the proximal screw postoperatively, and the fractures were refixed with distal cable wiring and/or femoral distal plates. The patients were subsequently discharged from the same facility with no remarkable pain. Conclusions: When inserting advanced locking screws, it is necessary to enlarge the screw hole in the near-bone cortex with a counterbore drill, which might add torque to the bone cortex that could result in fractures. If the sleeve is distant from the bone, the counterbore drill will not reach the bone, the screw hole will not expand, and the insertion of advanced locking screws will apply a strong torque to the bone cortex and may result in fracture. Moreover, it is important to confirm that the counterbore drill is securely inserted under fluoroscopy and to carefully enlarge the bony foramen manually to prevent fractures during screw insertion.
Long-Term Efficacy and Safety of Direct Oral Anticoagulants at Reduced Doses in the Secondary Prevention of Venous Thromboembolism and Post-Thrombotic Syndrome
Authors: Costanzo Luca , Di Paola Federico , Pedi Anastasia , Failla Giacomo , Mangiafico Marco
Published: April 2024

Background: Anticoagulation for venous thromboembolism (VTE) is required for at least three to six months; however, it is advisable to extend the duration in certain cases, in which case a reduced dose of Direct Oral Anticoagulants (DOACs) may be an option. Our objective was to investigate the efficacy and safety of reduced-dose DOACs in extended anticoagulation treatment compared to full doses. Methods and Results: This retrospective single-centre study included 185 patients treated with DOACs for at least 6 months who were divided into two groups: (1) the Full Dose (FD) group (n = 113) and (2) the Reduced Dose (RD) group (n = 72), which included patients treated with Apixaban at 2.5 mg bis in die (BID) and Rivaroxaban at 10 mg once daily (OD). Post-thrombotic syndrome (PTS) and its progression were evaluated. During an overall follow-up of 48.32 ± 29.49 months, no VTE occurred, and no patients experienced major bleeding; clinically relevant non-major bleeding occurred in three patients in each group (2.7% vs. 4.2% in FD vs. RD, respectively, p = 0.57). From baseline to follow-up, the prevalence of PTS was not significantly decreased in either group (FD: 54.9% vs. 51.3%, p = 0.29; RD 51.4% vs. 44.4%, p = 0.12); conversely, the Villalta score values were significantly decreased at the last follow-up (FD: 5.51 ± 4.18 vs. 5.12 ± 4.36, p < 0.001; RD 5.49 ± 4.06 vs. 5.11 ± 3.73, p = 0.006). Conclusion: In this real-world retrospective registry, very long-term extended anticoagulant therapy with DOACs at full or reduced doses showed comparable efficacy, safety, and impact on PTS progression. Larger studies are needed.
A Nomogram for Predicting ADHD and ASD in Child and Adolescent Mental Health Services (CAMHS)
Authors: Blasco-Fontecilla Hilario , Li Chao , Vizcaino Miguel , Fernández-Fernández Roberto , Royuela Ana , Bella-Fernández Marcos
Published: April 2024

Objectives: To enhance the early detection of Attention Deficit/Hyperactivity Disorder (ADHD) and Autism Spectrum Disorder (ASD) by leveraging clinical variables collected at child and adolescent mental health services (CAMHS). Methods: This study included children diagnosed with ADHD and/or ASD (n = 857). Three logistic regression models were developed to predict the presence of ADHD, its subtypes, and ASD. The analysis began with univariate logistic regression, followed by a multicollinearity diagnostic. A backward logistic regression selection strategy was then employed to retain variables with p < 0.05. Ethical approval was obtained from the local ethics committee. The models’ internal validity was evaluated based on their calibration and discriminative abilities. Results: The study produced models that are well-calibrated and validated for predicting ADHD (incorporating variables such as physical activity, history of bone fractures, and admissions to pediatric/psychiatric services) and ASD (including disability, gender, special education needs, and Axis V diagnoses, among others). Conclusions: Clinical variables can play a significant role in enhancing the early identification of ADHD and ASD.
Fertility Preservation in the Era of Immuno-Oncology: Lights and Shadows
Authors: Silvestris Erica , D’Oronzo Stella , Petracca Easter Anna , D’Addario Claudia , Cormio Gennaro , Loizzi Vera , Canosa Stefano , Corrado Giacomo
Published: April 2024

In recent years, immuno-oncology has revolutionized the cancer treatment field by harnessing the immune system’s power to counteract cancer cells. While this innovative approach holds great promise for improving cancer outcomes, it also raises important considerations related to fertility and reproductive toxicity. In fact, most young females receiving gonadotoxic anti-cancer treatments undergo iatrogenic ovarian exhaustion, resulting in a permanent illness that precludes the vocation of motherhood as a natural female sexual identity. Although commonly used, oocyte cryopreservation for future in vitro fertilization and even ovarian cortex transplantation are considered unsafe procedures in cancer patients due to their oncogenic risks; whereas, ovarian stem cells might support neo-oogenesis, providing a novel stemness model of regenerative medicine for future fertility preservation programs in oncology. Recent scientific evidence has postulated that immune checkpoint inhibitors (ICIs) might in some way reduce fertility by inducing either primary or secondary hypogonadism, whose incidence and mechanisms are not yet known. Therefore, considering the lack of data, it is currently not possible to define the most suitable FP procedure for young patients who are candidates for ICIs. In this report, we will investigate the few available data concerning the molecular regulation of ICI therapy and their resulting gonadal toxicity, to hypothesize the most suitable fertility preservation strategy for patients receiving these drugs.
Data-Driven Position and Stiffness Control of Antagonistic Variable Stiffness Actuator Using Nonlinear Hammerstein Models
Authors: Javadi Ali , Haghighi Hamed , Pornpipatsakul Khemwutta , Chaichaowarat Ronnapee
Published: April 2024

In this paper, an optimal PID controller is introduced for an antagonistic variable stiffness actuator (AVSA) based on Hammerstein models. A set of Hammerstein models is developed for the AVSA using the voltage difference method. For each stiffness level, linear and nonlinear Hammerstein models are identified using the least squares method. Experimental results confirm that the outputs of the Hammerstein models fit the measured data better than linear models, as Hammerstein models can incorporate nonlinear effects such as friction. A genetic algorithm is utilized to find optimal PID gains for different stiffness levels and reference position amplitudes. The final gains are obtained by linearly interpolating the optimal gains obtained. To demonstrate the effectiveness of the proposed design, several scenarios with different reference positions and stiffness profiles are provided. Specifically, square, sinusoidal, and sawtooth waves are used for reference positions and stiffness values. The robustness of the proposed approach is further analyzed by applying a disturbance force on the actuator link. The results are compared with the linear method, showing that the proposed design can handle soft transitions in stiffness variation and ensure perfect tracking.
The Use of Pre-Endoscopic Metoclopramide Does Not Prevent the Need for Repeat Endoscopy: A U.S. Based Retrospective Cohort Study
Authors: Ayoub Mark , Faris Carol , Tomanguillo Julton , Anwar Nadeem , Chela Harleen , Daglilar Ebubekir
Published: April 2024

Background: Peptic ulcer disease (PUD) can cause upper gastrointestinal bleeding (UGIB), often needing esophagogastroduodenoscopy (EGD). Second-look endoscopies verify resolution, but cost concerns prompt research on metoclopramide’s efficacy compared to erythromycin. Methods: We analyzed the Diamond Network of TriNetX Research database, dividing UGIB patients with PUD undergoing EGD into three groups: metoclopramide, erythromycin, and no medication. Using 1:1 propensity score matching, we compared repeat EGD, post-EGD transfusion, and mortality within one month in two study arms. Results: Out of 97,040 patients, 11.5% received metoclopramide, 3.9% received erythromycin, and 84.6% received no medication. Comparing metoclopramide to no medication showed no significant difference in repeat EGD (10.1% vs. 9.7%, p = 0.34), transfusion (0.78% vs. 0.86%, p = 0.5), or mortality (1.08% vs. 1.08%, p = 0.95). However, metoclopramide had a higher repeat EGD rate compared to erythromycin (9.4% vs. 7.5%, p = 0.003), with no significant difference in transfusion or mortality. Conclusions: The need to repeat EGD was not decreased with pre-EGD use of metoclopramide. If a prokinetic agent is to be used prior to EGD, erythromycin shows superior reduction in the need of repeat EGD as compared to metoclopramide.
Chloro(η2,η2-cycloocta-1,5-diene){1-benzyl-3-[(S)-2-hydroxy-1-methylethyl]benzimidazol-2-ylidene}rhodium(I)
Authors: Sakaguchi Satoshi , Matsuo Shogo
Published: April 2024

Previously, we demonstrated the synthesis of a well-defined hydroxyalkyl-functionalized N-heterocyclic carbene (NHC)/Ru(II) complex through the transmetalation reaction between [RuCl2(p-cymene)]2 and the corresponding NHC/Ag(I) complex derived from a chiral benzimidazolium salt using the Ag2O method. In this study, we successfully synthesized [RhX(cod)(NHC)] complexes through a one-pot deprotonation route. The hydroxyalkyl-substituted benzimidazolium salt reacted with [Rh(OH)(cod)]2 in THF at room temperature, affording the corresponding monodentate NHC/Rh(I) complex in nearly quantitative yield. The rhodium complex was characterized using NMR, HRMS measurement, and elemental analysis.
Impact of ZrO2 Content on the Formation of Sr-Enriched Phosphates in Al2O3/ZrO2 Nanocomposites for Bone Tissue Engineering
Authors: Nunes Fabio Caixeta , Santos Sarah Ingrid Pinto , Colnago Luiz Alberto , Hammer Peter , Ferreira Julieta Adriana , Ambrósio Carlos Eduardo , Pallone Eliria Maria
Published: April 2024

This study investigates the profound impact of the ZrO2 inclusion volume on the characteristics of Al2O3/ZrO2 nanocomposites, particularly influencing the formation of calcium phosphates on the surface. This research, aimed at advancing tissue engineering, prepared nanocomposites with 5, 10, and 15 vol% ZrO2, subjecting them to chemical surface treatment for enhanced calcium phosphate deposition sites. Biomimetic coating with Sr-enriched simulated body fluid (SBF) further enhanced the bioactivity of nanocomposites. While the ZrO2 concentration heightened the oxygen availability on nanocomposite surfaces, the quantity of Sr-containing phosphate was comparatively less influenced than the formation of calcium phosphate phases. Notably, the coated nanocomposites exhibited a high cell viability and no toxicity, signifying their potential in bone tissue engineering. Overall, these findings contribute to the development of regenerative biomaterials, holding promise for enhancing bone regeneration therapies.