bluuebunny/crossref_metadata_2025 huggingface dataset:
Correlation between Preoperative Blood Pressure Variability and Carotid Sinus Reaction after Internal Carotid Artery Stenting
Authors: Zhao Xinxiu , Tong Zhengyu , Yin Liang , Luo Song , Li Yuyu , Shi Peng , Qian Weidong
Published: February 2025

AIM: To investigate the relationship between blood pressure variability (BPV) 24 hours before internal carotid artery stenting and post-procedural carotid sinus reaction (CSR), with an emphasis on identifying BPV indexes that predict the implementation of carotid artery stenting (CAS) and the subtype of CSR.
METHODS: A total of 105 patients who completed 24-hour ambulatory blood pressure monitoring and underwent CAS from August 2019 to February 2024 in the First Affiliated Hospital of Bengbu Medical College were included in this study. Patients were divided into CSR and non-CSR groups. The CSR group was further divided into three subgroups according to the type of CSR that occurred: namely hypotensive, bradycardic, and mixed types. Prior to stent placement, changes in ambulatory blood pressure were monitored using a fully automated non-invasive portable blood pressure monitor for 24 hours before the procedure, and the individual metrics in BPV were compared.
RESULTS: CSR occurred in 69 patients (65.71%) and the remaining 36 patients did not experience CSR (34.29%). Among the patients with CSR, 46 (66.67%) experienced hypotensive CSR, 9 (13.04%) had bradycardic CSR, and 14 (20.29%) mixed-type CSR. The age, history of hypertension, coronary artery disease, and history of smoking were significantly higher in the CSR group than in the non-CSR group (p = 0.007, p = 0.002, p = 0.046, p = 0.007, respectively). Age, hypertension, and history of smoking were the risk factors for CSR. A statistically significant difference in triglyceride levels was found between the three subgroups of CSR (p < 0.05); however, triglycerides had no significant effect on the type of CSR subgroups (all p > 0.05). A series of preoperative BPV indexes, like the maximum systolic blood pressure (SBP), SBP's max-min difference, mean, standard deviation (SD), coefficient of variation (CV), and degree of variability (SV) of the 24-hour SBP, were significantly correlated with the occurrence of CSR (p < 0.05). Further analysis revealed that SBP's max-min difference, SD, CV, and SV of 24-hour SBP were independent predictors of CSR. The bradycardic CSR was significantly correlated with the maximum diastolic blood pressure (DBP), minimum DBP, and 24-hour mean DBP, when compared to the hypotensive CSR (p < 0.05). The mixed-type CSR was significantly correlated with the maximum DBP and minimum DBP, when compared to the bradycardic CSR (p < 0.05).
CONCLUSIONS: The indexes of BPV 24 hours before internal carotid artery stenting correlate with the occurrence and types of CSR. Therefore, BPV can be used as a predictor of the occurrence and specific type of CSR after internal carotid artery stenting.
Incidence and Outcomes of Low Anterior Resection Syndrome in Patients Undergoing Preventive Ostomy for Laparoscopic Rectal Cancer Surgery
Authors: Luo Guizhi , Lu Jinhong , Yang Youzhuan , Ma Hongchao
Published: February 2025

AIM: This study aimed to explore the incidence and risk factors of low anterior resection syndrome (LARS) in patients undergoing preventive colostomy following laparoscopic rectal cancer surgery. Additionally, the outcomes of LARS were analyzed to provide evidence for effective prevention and treatment strategies.
METHODS: The medical records of 143 patients with laparoscopic rectal cancer who underwent preventive ostomy at the Zhujiang Hospital of Southern Medical University between January 2020 and October 2022 were retrospectively reviewed. All patients underwent ostomy reversal within 2 to 6 months post-surgery. The LARS score scale was used to evaluate the occurrence of LARS at 3, 6, and 12months post-surgery. Based on LARS scores, patients were divided into LARS and non-LARS groups. Clinical characteristics, including gender, TNM stage, and other related data, were compared between the two groups. Multivariate logistic regression analysis was conducted to identify risk factors for LARS, and the predictive performance of the regression model was evaluated using the receiver operating characteristic (ROC) curve.
RESULTS: The LARS score demonstrated a significant decrease over time after surgery (p < 0.05). LARS was identified in 80 patients (55.94%) at 3 months post-surgery, with no new cases reported after this period. Statistically significant differences between the LARS and non-LARS groups were observed in body mass index (BMI), tumor distance from the anal margin, postoperative anastomotic fistula, and the timing of ostomy reversal (p < 0.05). The ROC curve analysis revealed that the logistic regression model predicting LARS had an area under the curve (AUC) of 0.809 (95% CI: 0.735–0.870), with a sensitivity of 76.25% and a specificity of 79.37%. Among the LARS patients 3 months post-surgery, 73.75% (59/80) showed improvement by 12 months. The improvement rate in patients with mild LARS (87.93%) was significantly higher than in those with severe LARS (36.36%) (p < 0.05).
CONCLUSIONS: The incidence of LARS is relatively high in patients undergoing preventive ostomy after laparoscopic rectal cancer surgery. Key factors associated with LARS include BMI, tumor distance from the anal margin, postoperative anastomotic fistula, and the timing of ostomy reversal. Over time, the incidence of LARS decreases, and outcomes improve, especially in patients with mild LARS.
Comparative Study on the Efficacy and Safety of Emergency Surgery Versus Endoscopic Stent Placement Followed by Definitive Surgery in the Treatment of Colorectal Obstruction
Authors: Jin Zhekang , Jin Xihan , Lu Jiying
Published: February 2025

AIM: Tumor-induced acute intestinal obstruction is a severe complication that poses significant threats to patient life. Emergency surgery is a widely used treatment method, but this approach has certain limitations such as high mortality and complication rates. Developments in endoscopic and minimally invasive techniques have provoked interest in postoperative definitive resection or conservative treatment following colorectal stent placement. Hence, this study aims to explore the clinical efficacy and safety of endoscopic-guided, X-ray-assisted intestinal stent placement in colorectal cancer (CRC) with acute intestinal obstruction, and to provide clinicians with viable alternative treatment options to enhance patient care.
METHODS: This study included 69 CRC patients who received treatment at the Affiliated Jinhua Hospital, Zhejiang University School of Medicine, China, between August 2017 and August 2021. The control group (n = 38) underwent emergency laparotomy with one-stage resection and stoma formation, followed by a postoperative second-stage stoma closure every 3 to 6 months. Moreover, the experimental group (n = 31) underwent endoscopic stent placement followed by definitive surgery. The differences in various indicators were compared between groups. Additionally, the 1-year and 3-year overall survival (OS) rates and disease-free survival (DFS) rates were compared between groups.
RESULTS: Successful placement of intestinal stents was achieved in all 31 patients, with acute intestinal obstruction relief within 24 to 48 hours. In the experimental group, stent placement effectively relieved intestinal obstruction, and a postoperative radical colon surgery was performed after 7 to 10 days. The experimental group had significantly lower rates of postoperative ventilator time, reduced time to oral intake, and fewer complication than the control group (p < 0.05). However, no significant differences were observed between groups regarding operation time, intraoperative blood loss, 1-year and 3-year OS rates, and 1-year and 3-year DFS rates (p > 0.05).
CONCLUSIONS: Compared to emergency surgery, combined endoscopic and X-ray-guided colonic stent placement is an effective and safer method for alleviating acute intestinal obstruction in colorectal cancer. This study provides valuable insights to clinicians in selecting treatment options.
Clinical Outcomes of DAMIS Traction Table-Assisted Anterior Approach versus Posterolateral Approach on Total Hip Arthroplasty in the Treatment of Femoral Head Necrosis
Authors: Lu Mao-sen , Zhang Yan-ping , Jiao Yong-jie , Wang Long , Meng Xin , Zhang Jie , Du Min , Hu Han-zhen , Du Jian-wei , Liu Chang-feng
Published: February 2025

AIM: Femoral head necrosis often leads to hip joint dysfunction, which can be effectively treated with total hip arthroplasty (THA). This study compares the clinical outcomes of direct anterior minimally invasive surgery (DAMIS) traction table-assisted anterior approach and the traditional posterolateral approach (PLA) on THA for femoral head necrosis.
METHODS: A total of 150 patients with femoral head necrosis, admitted between September 2019 and May 2022, were included in this study. In this sample, 68 patients underwent THA via the PLA (control group), while the remaining 82 patients were treated with THA using the DAMIS traction table-assisted anterior approach (observation group). The surgical-related indicators, postoperative pain scores, Harris hip scores (HHS), and rates of complication incidence between the two groups were compared.
RESULTS: There were no significant differences in surgery time between the two groups (p = 0.054). The observation group had significantly less intraoperative blood loss (p = 0.018), shorter incision length (p = 0.001), and significantly shorter time elapsed to first out-of-bed activity (p = 0.016) and shorter hospital stay compared to the control group (p = 0.001). The postoperative pain scores in the observation group were significantly lower than in the control group (p = 0.001), and the HHS at 2 weeks and 4 weeks after surgery were significantly higher in the observation group (p < 0.05). The overall complication rate in the observation group was significantly lower than in the control group (p = 0.011).
CONCLUSIONS: DAMIS traction table-assisted anterior approach for THA demonstrates clinical advantages in the treatment of femoral head necrosis, effectively accelerating postoperative recovery and reducing the occurrence of complications.
Analysis of Risk Factors and Preventive Measures for Perioperative Incision Infection in Patients Receiving Rigid Internal Fixation of Maxillofacial Fractures
Authors: Xu Fengxing , Wang Fan
Published: February 2025

AIM: To analyze the risk factors for perioperative incision infection in patients undergoing rigid internal fixation for maxillofacial fractures and the prevention and control measures formulated to enhance the effect of surgical treatment.
METHODS: We retrospectively analyzed the medical records of 342 maxillofacial fracture patients who received rigid internal fixation treatment at the Department of Stomatological Surgery of The First People's Hospital of Yongkang (Yongkang First People's Hospital) from May 2018 to April 2023, and divided them into the uninfected group (n = 308) and the infected group (n = 34) according to their history of perioperative incision infections. Data from the subjects on age, type of fracture trauma and length of hospitalization were collected and analyzed. Multifactorial logistic regression analysis was employed to explore the risk factors for perioperative incision infections in these patients and to develop preventive measures for these risk factors.
RESULTS: The study found that the incidence of incision infections was 9.94% (34/342) in 342 patients. Multifactorial logistic regression analysis showed that the incidence of incision infections was significantly higher in patients with comorbid diabetes mellitus versus those without comorbid diabetes mellitus (odds ratio [OR] = 9.543, 95% confidence interval [CI]: 1.818–50.095, p = 0.008); patients undergoing surgery in summer versus those in other seasons (OR = 8.483, 95% CI: 1.476–48.744, p = 0.017); and malnourished patients versus those with good nutritional status (OR = 5.163, 95% CI: 1.016–26.231, p = 0.048). In addition, the analysis also revealed that incision size was also a risk factor for incision infections during the postoperative period (OR = 2.882, 95% CI: 1.567–5.304, p = 0.001), whereas a higher preoperative albumin level was a protective factor (OR = 0.755, 95% CI: 0.639–0.891, p = 0.001).
CONCLUSIONS: A plethora of risk factors can lead to incision infection in patients with maxillofacial fracture during perioperative period. Therefore, preventive measures should be implemented in the hospitals to control these factors in order to reduce the occurrence of complications and enhance the effectiveness of surgical treatment.
The Axes of the Controversial Linguistic Foundations according to Sibawayh
Authors: Aldalabih Mohammad Fadl Thlji
Published: February 2025

The primary objective of this research is not to present the controversial aspects between Sibawayh and other scholars, but rather to examine the foundations that Sibawayh used to support his linguistic opinions, which were often opposed by others. The key foundations that Sibawayh relied upon include auditory, analogy, and interpretative axes, as well as deviations from traditional Arab linguistic practices and the languages spoken by the Arabs. Additionally, this research will discuss other relevant foundations throughout. Sibawayh may refer to one of these axes when comparing the opinions of scholars, categorizing some as easy, others as strong, and others with different attributes. The research paper concludes with a series of findings based on this analysis.
Potential of Biomaterial as a Medical Fiber using Electrospinning Method: A Review
Authors: Setyaningsih Agustina , Wardhani Dyah Hesti
Published: February 2025

With the growing demand for wound care worldwide, the quality of medical equipment continues to advance, driven by the increasing need for more effective and efficient treatment solutions. The rapid growth of the healthcare industry, coupled with technological advancements, has led to significant improvements in wound management techniques. However, despite these advancements, medical fibers remain the primary tools used by healthcare professionals for wound closure due to their versatility, biocompatibility, and effectiveness in promoting healing. One of the most promising techniques for fabricating medical fibers is electrospinning, a widely recognized method for producing ultrafine fibers from a broad range of starting materials, including synthetic and natural polymers. Among the various fiber production techniques available today, electrospinning stands out as a superior method due to its ability to generate fibers with diameters ranging from nanometers to microns. This process is not only efficient and relatively simple but also offers precise control over fiber morphology, porosity, and mechanical properties. Such characteristics make electrospun fibers highly suitable for biomedical applications, particularly in tissue engineering, drug delivery systems, and wound healing. In recent years, the use of natural polymers as biomaterials for electrospinning has gained significant attention, as they offer excellent biocompatibility, biodegradability, and minimal risk of adverse reactions. Polymers such as alginate, chitosan, gelatin, and glucomannan have been extensively studied for their potential in medical applications. Their inherent bioactive properties contribute to enhanced cell adhesion, proliferation, and overall wound healing efficiency. This paper aims to provide a comprehensive review of the latest advances in the potential of biomaterials as fibers—particularly focusing on their structural characteristics, functional modifications, and research developments. Additionally, the discussion will explore their applications in modern medicine and how their properties can be optimized to meet evolving medical needs.
Utilizing Non-Marketable Dates as a Sugar Substitute in Producing Nutritionally Balanced Functional Biscuits
Authors: Al-Huthaly Suha M. , El-Hady El Sayed Abd , Shabib Zeinab , Alsaleem Khalid , Almarzooq Ahmed , Aladhadh Mohammed , Alayouni Raed
Published: February 2025

Dates are an important national resource in Saudi Arabia, with significant efforts focused on increasing production, enhancing quality, and utilizing surplus dates for health-oriented food products. This study investigates the technological role of powdered low-quality Sukkari dry dates as a sugar substitute in balanced functional biscuits that are rich in fiber and minerals while being low in calories. The study assessed the effects of substituting sugar with powdered dates at levels of 25%, 50%, and 75%, focusing on the optimal substitution ratio for high-quality biscuits. The findings revealed that the powdered date substitution influenced the dough's rheological properties, including a decrease in water absorption, an increase in dough formation time, and a reduction in mixing tolerance at higher substitution levels. The sugar reduction led to a decrease in calories and carbohydrates, while protein and ash content increased. Color analysis showed reduced lightness and yellowness, with an increase in redness and darker tones as the substitution level rose. Sensory evaluations indicated that biscuits with 25% substitution were highly acceptable, scoring 94.90%, comparable to the control sample's 97.15%. Biscuits with up to 50% substitution were also deemed acceptable, highlighting the potential of Sukkari dates as a balanced functional and healthier sugar alternative in biscuit production.
Unravelling D&D within the maritime ecosystem and its influence on IWT in port-hinterland supply chains
Authors:   , Storms Katrien
Published: February 2025

The use of intermodal inland waterway transport (IWT) is a key European strategy to move towards climate-neutral transport. However, challenges such as COVID-19, extreme Rhine water levels, and geopolitical disruptions complicate the shift from road to IWT. These disruptions often result in additional costs, known as demurrage and detention (D&D). This dissertation researches the impact of D&D practices on IWT within Europe’s port-hinterland supply chain. Using a SARIMAX modeling, it forecasts IWT container volumes on the Rhine and highlights the potential impact of disruptions on IWT recovery. Findings from surveys, discussions, and legal analyses reveal inefficiencies in D&D practices and propose solutions such as extended free time for IWT, digitalization, and improved negotiation strategies. Cost analyses show that D&D fees can exceed the shipping lines’ opportunity costs as time passes, suggesting their role as a revenue stream. Nevertheless, shippers can leverage D&D into their storage strategies to optimize costs. Furthermore, D&D and terminal dwell times significantly influence IWT's modal share. Consequently, addressing D&D is important in making a shift towards more sustainable and efficient hinterland transport.
India's Criminal Justice Reform: An In-Depth Look at The New Laws
Authors: A. S. Kowshikaa
Published: February 2025

The recent enactment of the Bharatiya Nyaya Sanhita (BNS), Bharatiya Nagarik Suraksha Sanhita (BNSS), and Bharatiya Sakshya Adhiniyam (BSA) marks a monumental shift in India's criminal justice system, replacing colonial-era laws with a modern legal framework. These reforms aim to streamline judicial processes, enhance transparency, and prioritize justice for victims. This paper provides a comprehensive analysis of the new laws, focusing on substantive changes in criminal offenses, police investigation procedures, and judicial proceedings. Key innovations include gender-neutral language, mandatory forensic investigations, community service for specific offenses, and extended police custody under defined circumstances. The integration of advanced technology, such as Zero FIR and digital evidence management, aims to make justice more accessible and victim-centric. While these changes offer significant improvements, the paper also highlights potential gaps and challenges, particularly concerning procedural ambiguities and the risk of misuse of police discretion. The reforms represent a promising step forward but require continuous assessment to ensure fair and effective implementation in line with constitutional principles. In this Article the Author tries to analyse the various initiatives taken by the Government in enacting the new criminal legislation which will transform the Criminal law in India.
Top 10 Skills Every Aspiring Translator Should Master
Authors: Heyderova Nahide
Published: February 2025

This article examines the top skills that aspiring translators must master to succeed in the ever-evolving field of translation. It delves into the foundational importance of linguistic proficiency and cultural competence, emphasizing how these skills enable translators to deliver accurate and contextually appropriate translations. Additionally, the article explores the growing relevance of technological proficiency, particularly in using CAT tools and machine translation systems, and highlights the need for lifelong learning and adaptability to keep pace with industry trends. By addressing the challenges of skill acquisition and offering practical strategies for professional growth, this article aims to inspire translators to embrace opportunities for continuous development and thrive in their careers.
REUNIÃO FAMILIAR NO BRASIL: ILEGALIDADE DO ART. 153, §2º, DO DECRETO N. 9.199/2017 AO ESTABELECER QUE O CHAMADO NÃO PODE SER CHAMANTE
Authors: Barni Adriana Regina
Published: February 2025

O presente trabalho pretende analisar o art. 153, §2º, do Decreto n. 9.199/2017, que proíbe o chamado de ser chamante, e sua incompatibilidade com os termos da Lei de Migração. Isso porque o Decreto referido tem por objetivo regulamentar a Lei n. 13.445/2017, logo, pelo princípio da hierarquia das normas, não poderia contrariar ou extrapolar a lei, daí a razão de sua ilegalidade, porque, nesse particular, restringiu direito do migrante chamado, ao arrepio da respectiva Lei. Para tanto, este artigo analisa, em primeiro lugar, o próprio sistema de hierarquia das normas adotado no Brasil. Num segundo momento, busca examinar o conceito de família e a sua proteção no plano internacional e no ordenamento jurídico brasileiro para, a partir daí, falar do direito de toda e qualquer pessoa, como o próprio migrante, à unidade familiar, que é um direito baseado no princípio da dignidade da pessoa humana, proteção à família, entre outros. Por outro lado, pretende analisar o instituto da reunião familiar, como decorrência do direito à unidade familiar e a proteção à família para, então, examinar as disposições da Lei de Migração e do Decreto n. 9.199/2017 acerca das figuras do chamado e do chamante. O presente artigo tem por base o método de abordagem dedutivo, além de pesquisas bibliográficas e documental como método de procedimento.
O AUTISMO E A CONTRIBUIÇÃO DA PSICOPEDAGOGIA
Authors: Pereira Maria José de Jesus , Costa Evangelina Pereira
Published: February 2025

O  presente  artigo  tem  como  objetivo  investigar  o  autismo  e  saber  como  se  desenvolve.  Neste  estudo  pretende-se  abordar  as  características  do  autista,  bem  como  a  contribuição  da  psicopedagogia  e  como  se  dá  a  aprendizagem  do  mesmo.  Para  tanto,  foram  utilizadas  pesquisas  bibliográficas  referente  a  essa  temática.  Como  aporte  teórico  dialogaremos  com  as  obras  de  Cunha (2014) ,  Mantoan  (  1992 ) ,  Feltrin  (  2004  )  entre  outros  que  abordam  sobre  o  autismo  e  a  deficiência  na  aprendizagem.  Este  estudo  visa  ampliar  e  contribuir  com  as  discussões  acerca  do  autismo.  Contudo,  pretende-se  apontar  alguns  tipos  de  transtornos  que  está  relacionado  ao  vínculo  afetivo-social  e  demostrando  a  importância  da  aprendizagem  de  acordo  com  estímulos  e  intervenção  psicopedagógica.  Neste  sentido  o  artigo  apresenta  uma  grande  relevância  na  educação  inclusiva  e  em  especial,  para  criança  com  autismo  e  interessados  na  área  como,  pesquisadores  ,comunidade  acadêmica.  No  entanto, a contribuição  da  psicopedagogia  no  que  se  refere  ao  autismo  é  de  extrema  relevância  para  o  sucesso  de  crianças  com  autismo,  oportunizando  o  desenvolvimento  cognitivo,  afetivo,  biológico  e  social,  por  meio  de  um  trabalho  eficaz.  Para  tanto  o  artigo  traz  em  sua  abordagem  o  breve  histórico  sobre  o  autismo,  das  características  e  apontamento  dos  tipos  de  transtornos,  aprendizagem,  fala  ainda  do  vínculo  afetivo-  social,  da  psicomotricidade,  consequentemente  avaliação  e  intervenção  psicopedagógica e o tratamento do transtorno do espectro autista.
Comparative Analysis of Biochemical and Cellular Profiles in Acute Gastroenteritis Patients with Comorbidities: A Retrospective Study in a Resource-Limited Setting
Authors: Kumari Hema , Kumar Gaurav
Published: February 2025

This study aims to compare critical laboratory parameters in patients diagnosed with acute gastroenteritis (AGE) with various comorbidities, highlighting trends and abnormalities in biochemistry and cellular profiles. Conducted at Yatharth Hospital, Greater Noida, India, this retrospective study includes 284 patients admitted between March 2018 and May 2022. Key parameters such as total leukocyte count (TLC), sodium, and liver enzymes (SGPT/SGOT) were evaluated and compared across different age groups and comorbidities, including dehydration, acute febrile illness, diabetes, and hypertension. Significant deviations were identified in patients with comorbidities, particularly in sodium levels and liver enzyme markers, which may aid in early detection and management. This study's findings provide valuable insights for resource-limited settings, contributing to more effective treatment strategies and resource allocation, especially in low- and middle-income countries (LMICs), where AGE remains a major health concern.
"The Impact of Organizational Values and Leadership in Strengthening the Workplace Spirituality: A Study of Employee Well-Being and Job Satisfaction"
Authors: G Ashwini. , M Dr. Supriya. , K Kalidas
Published: February 2025

Off recently the very topic of ‘Workplace Spirituality’ has derived the attention of the researches and managerial capacities across the globe. This enhanced attention is driven by the increased advantages of workplace spirituality and morality both at personal and administrative levels. Earlier managerial practitioners assumed workplace spirituality was purely religious or mystical and had no relevance for the organization. But nowadays, it is considered an essential element of organizational study as nature of the job seems to have changed significant. It is no longer an activity that has no connection to the personal development of an employee. The workplace has changed, becoming a place where people can grow spiritually. Now, employees are looking for a purpose in their employment beyond merely transacting economically with other lonely, independent people. Employees are also looking for an avenue to integrate the work lives with enlightened path and collaborate with others in their community, and share a vision and goal far beyond earning money.
Un Arreglo de Cosechadores de Energía Basado en Flutter: Ecuaciones de Movimiento
Authors: Aichino Agostina C. , Ribero Santiago , Pérez Segura Martín E. , Beltramo Emmanuel , Valdez Marcelo , Preidikman Sergio
Published: February 2025

Este artículo constituye la primera parte de una serie de dos documentos que tienen como objetivo el desarrollo e integración numérica, en el dominio del tiempo, de las ecuaciones de movimiento de un arreglo de cosechadores de energía basados en flutter. La formulación presentada en este trabajo permite considerar un arreglo de múltiples cosechadores de energía dispuestos en arreglos espaciales, inmersos en una corriente de aire inestacionaria, y acoplados aerodinámica y estructuralmente. En el modelo propuesto cada cosechador posee seis grados de libertad, está sometido a grandes desplazamientos y grandes rotaciones, y contempla la posibilidad de incluir condiciones de borde y de restricción tanto rígidas como elásticas. Las ecuaciones de movimiento se derivan utilizando una técnica que combina convenientemente las formulaciones de Newton-Euler y de Lagrange. Para facilitar su integración numérica, se expresan en forma matricial como un sistema de ecuaciones diferenciales ordinarias no-lineales y no-autónomas de primer orden.
Influencia del Tipo de Impacto en la Generación de Carga de un Recolector de Energía
Authors: Febbo Mariano , Oliva Alejandro , Machado Sebastián P.
Published: February 2025

En este trabajo se presenta un estudio sobre diferentes tipos de fuerzas de impacto para seleccionar cuál es el más conveniente para la generación de energía en piezoeléctricos. El análisis se basa en elegir entre pulsos de corta duración pero repetitivos o de gran duración aunque únicos. A partir de simulaciones se obtiene que pulsos de corta duración, discontinuos, inducen oscilaciones en el piezoeléctrico que no aparecen en pulsos de gran duración y continuos. A partir de la implementación de un circuito eléctrico de extracción de carga sincrónica se pueden aprovechar estas oscilaciones para maximizar la energía cosechada. Un índice basado en la energía permite concluir que la fuerza de pulsos discontinuos genera el doble que una fuerza de un único pulso continua.
Simulación Numérica de la Interacción Fluidodinámica entre Cilindro y Perfil Aerodinámico en Condiciones de Flutter para Diferentes Frecuencias de Vórtices de Von Karman
Authors: Herrera Matías A. , Scarabino Ana
Published: February 2025

Los dispositivos de cosecha de energía eólica representan una alternativa viable para la obtención de energía y en particular, para la alimentación de pequeños dispositivos electrónicos de bajo consumo instalados en zonas sin acceso a la red eléctrica, tales como dispositivos de adquisición de datos o instrumentales de medición de variables climáticas. En trabajos previos, se analizó numéricamente mediante Ansys Fluent, la interacción entre un cilindro y un perfil aerodinámico inmersos en una corriente de aire, para una determinada frecuencia de desprendimientos del cilindro. El perfil aerodinámico poseía propiedades de masa e inercia ajustados para obtener la condición de flutter en la corriente de aire, y se encontraba vinculado a un marco de referencia fijo mediante resortes que cuantifican sus rigideces a flexión y a torsión. Mediante tal arreglo, se cuantificó la interacción aerodinámica a partir del análisis del coeficiente de potencia del perfil (potencia adimensional, extraída del aire), para diferentes longitudes de separación entre cilindro y perfil. En el presente trabajo, se han realizado simulaciones adicionales para obtener el coeficiente de potencia del perfil, para otras frecuencias de desprendimientos del cilindro, logrando caracterizar la influencia de la frecuencia de desprendimientos en la captación de energía del perfil. Los resultados son analizados y comparados cualitativamente con resultados encontrados en la bibliografía.
Un Modelo Variacional 'Phase-Field' Asimétrico de la Fisuración Termoelástica de Materiales Cementicios
Authors: Orlando Antonio , Luege Mariela , Campra Agustina , Martinez José Alejandro , Alonso Leal Camila
Published: February 2025

Se deriva un modelo variacional phase–field de procesos termomecánicos de fisuración en materiales quasi-fragiles caracterizado por diferente comportamiento a traccion y compresión, por ejemplo en materiales cementicios. El modelo propuesto puede derivarse de la formulación energética para procesos independientes de la velocidad, por lo cual la propagación termo-mecánica de la fisura he obtenida por la evolución cuasi estática de los mínimos globales de un funcional energético de tipo mixto que tiene en cuenta tanto la energía de deformación elástica como la energía de disipación asociada con la evolución de la variable phase–field de fisuración y con el proceso térmico. La formulación propuesta otorga un marco natural para definir un esquema numérico consistente con la formulación variacional subyacente, a través de la derivación de cotas energéticas de la solución discreta del problema termomecánico. Dichas cotas son usadas para diseñar un algoritmo de backtracking con el cual es posible circunscribir la falta de convergencia del método de Newton debido a no convexidad del funcional que modela el problema mecánico. Se presentan resultados numéricos donde la fisuración se induce térmicamente a través de un shock térmico, la cual, a pesar de seguir patrones complejos, es posible reproducir con el presente modelo.
Estudio Numérico del Fenómeno de Oil Whip en Ejes Elásticos Soportados por Cojinetes Hidrodinámicos
Authors: Palavecino Jorge A. , Zanatta Martín , Cavalieri Federico J. , Márquez Damián Santiago
Published: February 2025

El oil whirl consiste en una inestabilidad de la película lubricante del cojinete hidrodinámico debido a una pérdida de su capacidad de carga en condiciones de baja solicitación. Está inestabilidad produce una vibración sub-sincrónica a la mitad de la velocidad de rotación del eje. Cuando la rotación alcanza el doble de la frecuencia natural, la frecuencia de vibración permanece constante y cercana al valor de la primera frecuencia de resonancia. Este último fenómeno se denomina oil whip y resulta perjudicial para la vida útil del rotor. En este trabajo se analiza el comportamiento de un rotor unidimensional elástico a partir del Método de Elementos Finitos. Se analizan casos de la literatura con discos y masas desbalanceadas para determinar sus efectos en la inestabilidad del eje. Se comparan también los resultados obtenidos a partir de utilizar modelos dinámicos lineales y no lineales para la representación de los cojinetes hidrodinámicos.
Desafíos en la Simulación de Flujos Dominados por Vorticidad: Ventajas, Limitaciones y Perspectivas de la Incorporación de Partículas Vorticosas a los Métodos Tradicionales
Authors: Ribero Santiago , Pérez Segura Martín E. , Aichino Agostina C. , Beltramo Emmanuel , Roccia Bruno , Preidikman Sergio
Published: February 2025

El concepto de flujo dominado por vorticidad ha sido ampliamente utilizado en la formulación de métodos de simulación aerodinámica, con distintos niveles de éxito y aceptación. Este trabajo se centra en una extensión del método de red de vórtices inestacionario (UVLM) utilizando el método de partículas vorticosas (VPM), un modelo híbrido donde se representa el campo de vorticidad mediante una combinación de partículas y segmentos vorticosos. La incorporación de partículas ofrece como ventaja eliminar la estructura de malla de las estelas, pero su utilización puede resultar inestable y requiere consideraciones adicionales para su implementación. En este sentido, se analiza una serie de casos de estudio para destacar las virtudes, identificar los posibles inconvenientes y formular recomendaciones sobre el uso de partículas vorticosas en métodos de simulación de flujos dominados por vorticidad. Los resultados obtenidos colaboran con el entendimiento de los desafíos asociados con la implementación del VPM y proporcionan perspectivas valiosas sobre cómo aprovechar sus ventajas en diferentes aplicaciones de interacción aerodinámica y flujos alrededor de cuerpos sumergidos.
Simulación de un Convertidor Undimotriz de Péndulo Paramétrico con Miras a su Implementación en el Estuario de Bahía Blanca
Authors: Rojas Lisandro M. , Dotti Franco E. , Battaglia Laura , Storti Mario A.
Published: February 2025

Se presenta un modelo matemático de un sistema convertidor undimotriz compuesto por una rueda pendular excitada paramétricamente y un generador trifásico adosado a su eje pivot. El modelo permite el abordaje de la dinámica del sistema electromecánico acoplado, considerando además la electrónica de rectificación. El forzamiento aplicado corresponde a una simplificación de aquél generado por el movimiento del oleaje, el cual es cuantificado a partir de mediciones en el estuario de Bahía Blanca. El objetivo principal del estudio es el de establecer la relación entre la geometría de la rueda pendular y la potencia eléctrica generada. Se apunta además a establecer rangos de forzamiento dentro de los cuales sean posibles respuestas rotatorias del péndulo.
Estudios Analíticos y Experimentales de Recolectores de Energía Piezoeléctricos de Geometría Circular: Análisis de la Influencia de Grandes Aceleraciones para Diferentes Frecuencias
Authors: Vera Carlos A. , Machado Sebastián P. , Febbo Mariano
Published: February 2025

Los recolectores de energía piezoeléctricos de geometría circular, conocidos como buzzer, son estudiados cada vez con mayor interés, dada su versatilidad mecánica y bajo costo en comparación a recolectores con otras geometrías. En el presente artículo se presenta un modelo analítico unidimensional mejorado para simular la generación de voltaje obtenida a partir de un recolector de energía que utiliza un material piezoeléctrico tipo “buzzer”. El objetivo principal del artículo es presentar una nueva formulación no lineal que permita analizar la influencia de grandes aceleraciones sobre el comportamiento del recolector de energía. Los resultados obtenidos con el modelo matemático, lineal y no lineal son comparados con ensayos experimentales en laboratorio. La frecuencia de resonancia para máxima generación es cercana a los 140 Hz, donde la sintonización se logra mediante el diseño de una masa central que permite flexibilizar el dispositivo recolector.
Una Formulación Mixta para el Problema de Poisson Fraccionario
Authors: Angulo Wilfredo , Borthagaray Juan Pablo , De León Nahuel
Published: February 2025

La formulación mixta del problema de Poisson clásico consiste en introducir un flujo como nueva variable con condiciones de borde adecuadas, obteniendo un sistema de ecuaciones acopladas. Usando identidades del cálculo fraccionario, en este trabajo exploramos una formulación mixta del problema de Poisson fraccionario y probamos que el problema está bien planteado. Una discretización directa del problema no es posible, por lo que siguiendo ideas de Hughes y Masud introducimos una formulación estabilizada, que da lugar a un problema coercivo y bien planteado. La coercividad implica que cualquier discretización por elementos finitos conforme sea estable. Por último, obtenemos la convergencia de estas discretizaciones y discutimos su implementación.
Nueva Metodología para la Diferenciación de Señales Discretas Unidimensionales mediante el Empleo de Características Geométricas
Authors: García Blesa Hernán M. , Vorobioff Juan , Legnani Walter
Published: February 2025

El presente estudio se centra en la aplicación de un algoritmo para la clasificación de sistemas dinámicos caóticos, incluyendo los sistemas de Henón, Chirikov, Schuster, Logístico y el modelo poblacional de Ricker. El algoritmo utiliza como mecanismo principal la técnica de barrido, para la cual se define una dimensión de embedding y un parámetro de discretización. La clasificación de los sistemas dinámicos caóticos se lleva a cabo mediante la extracción de características geométricas. La metodología utiliza tres elementos: magnitud de la señal, ángulo de Zenit y un factor de forma, generando ternas y reduciendo aquellas que se repiten durante el proceso. A partir de estos datos se crea un espacio de características donde cada vector es único. Además de la clasificación, se lleva a cabo un análisis detallado del espacio generado por el algoritmo, el cual proporciona información adicional que complementa la clasificación realizada.
Una Generalización del Algoritmo Physarum para la Solución del Problema de Asignación de Tráfico Urbano
Authors: Dominguez Patricia N. , Cortínez Víctor H. , Peinado María L.
Published: February 2025

En este trabajo se propone un modelo evolutivo discreto, desarrollado a partir del enfoque Physarun, para abordar el problema de la asignación de tráfico en redes urbanas. Se presta especial atención a dos aspectos clave: a) la restricción de capacidad en las vías de comunicación, garantizando que no se generen flujos no factibles y b) la consideración de funciones de costo no locales, las cuales tienen en cuenta, no solamente el flujo vehicular propio de cada arco, sino también la influencia de otros arcos dentro de la red. Se detalla la formulación matemática del problema y se incluyen ejemplos que demuestran la eficiencia del enfoque propuesto.
Modelado de Aleaciones de ZR Recubiertas con CR para Combustibles de Tecnología Avanzada
Authors: Loza Peralta Matias E. , Soba Alejandro
Published: February 2025

Desde hace unas décadas, ha comenzado el desarrollo de combustibles nucleares destinados a reactores de generación IV. Muchos de estos combustibles se diseñan con paradigmas basados en nuevos parámetros de seguridad, por lo que ingresan en los llamados combustibles de tecnología avanzada (Advanced Technology Fuel). La base de esos diseños consiste en implementar cualquier mejora que permita mejorar los márgenes de seguridad de un reactor nuclear. La OIEA lidera un proyecto de investigación coordinado a nivel internacional, "Testing and Simulation for Advanced Technology and Accident Tolerant Fuels" (CRP ATF-TS), que promueve la experimentación y modelado de este tipo de combustibles. La Comisión Nacional de Energía Atómica, a través de la Sección Códigos y Modelos, contribuye con este proyecto integrando una librería de materiales ATF en el código DIONISIO 3.0. Se han estudiado hasta el momento materiales como pastillas dopadas con óxido de cromo, pastillas de óxidos mixtos de Torio, y vainas de FeCrAl. Este trabajo se enfoca en las vainas de Zr recubiertas con Cr, que pretenden mejorar la seguridad al evitar la falla de la primera barrera de contención por mecanismos de oxidación e hidruración. De esta manera se presentan los avances en la inclusión de modelos para estas vainas y se comparan con datos experimentales del proyecto ATF-TS.
Impacto de entornos virtuales en la enseñanza desde la perspectiva docente en Lima, 2024
Authors: Gayo García Milagros , Arris Rodríguez María Beatriz , Ponte Quiñones Elvis Jerson
Published: February 2025

Este estudio, realizado analiza el impacto de los entornos virtuales en la educación desde la perspectiva de los docentes en Lima, 2024. Su objetivo fue comprender cómo los maestros han enfrentado los retos y transformaciones en sus prácticas pedagógicas al adaptarse a espacios digitales, especialmente después de la pandemia, la metodología fue de enfoque cualitativo, de diseño fenomenológico, donde se aplicó como técnica la entrevista a 10 docentes. Las conclusiones destacan que, si bien los entornos virtuales ofrecen flexibilidad y oportunidades de innovación, los docentes enfrentan desafíos como la falta de conectividad, acceso a tecnología y la necesidad de apoyo emocional y técnico. A pesar de estas limitaciones, muchos docentes lograron adaptar sus métodos, promoviendo un aprendizaje dinámico y colaborativo en sus aulas virtuales. La investigación subraya la importancia de reducir las brechas tecnológicas para asegurar una educación inclusiva y de calidad.
Assessment of factors influencing academic performance of female students in Uganda certificate of education examinations in Manafwa Town council, Manafwa District, Uganda.
Authors:   ,   Uganda Martyrs University, Wamusi Julius
Published: February 2025

This study assessed factors influencing female students' academic performance in the Uganda certificate of education examinations in Manafwa Town Council in Manafwa District. The purpose of the study was to find out the factors responsible for poor academic performance. The study sought to find out the influence of parental, cultural and school factors respectively on the academic performance of female students. The study was conducted through a descriptive survey research design. Data was collected from 282 respondents using questionnaires and interview techniques. Quantitative data was analysed using SPSS computer software (Version 20) to generate frequencies and percentages. Qualitative data analysis was done through thematic content analysis. The study employed self- administered questionnaires to 183 senior four female students, 43 teachers and 5 head teachers. The number of respondents who were interviewed included 45 parents, 5 Local council one chairperson and 1 District inspector of schools. The findings revealed that academic performance of female students in Manafwa town council was poor because of parents’ failure to play their roles, domestic chores and lack of scholastic materials. The study concludes that poor academic performance of female students, is as result of parents’ failure to play their roles, shortage of teachers and lack of counselling and guidance to students. It is recommended that recommends that parents should endeavour to meet their parental obligations and allow enough time to their daughters while at home to do private reading to improve their academic performance. The Government should also equip the schools with necessary teaching/learning resources to avert the poor academic performance in Manafwa town council in Manafwa district.
ITRACONAZOLE SELF-NANOEMULSIFYING DRUG DELIVERY SYSTEM: A COMPREHENSIVE STUDY ON BCS CLASS II DRUG TRANSFORMATION FOR OPTIMAL ORAL DELIVERY
Authors: Rauf Abdul , Fahad Pervaiz  , Abid Hafiz Muhammad Usman , Khadija Karim  , Sadia Rehman  , Memoona Qayyum  , Mudassara Liaqat  , Rida Akhtar  , Tahreem Arshad  , Abdul Hassan Khan
Published: February 2025

Background: Itraconazole, a BCS Class II antifungal agent, exhibits poor water solubility and variable oral bioavailability, limiting its therapeutic efficacy. Self-nanoemulsifying drug delivery systems (SNEDDS) have emerged as an effective strategy for improving drug dissolution and absorption. By enhancing solubility and ensuring rapid drug release, SNEDDS formulations offer a promising alternative to conventional dosage forms. This study focuses on the development and evaluation of an optimized SNEDDS formulation for itraconazole to improve its oral bioavailability and therapeutic potential.
Objective: This study aimed to formulate and characterize an optimized SNEDDS for itraconazole, ensuring improved solubility, stability, and dissolution performance compared to conventional formulations.
Methods: Pseudo-ternary phase diagrams were employed to optimize the formulation, selecting oleic acid as the oil phase, Tween 80 as the surfactant, and PEG 200 as the co-surfactant. Twenty-seven formulations were initially prepared, out of which six were shortlisted based on isotropic properties. Formulations underwent rigorous characterization, including visual inspection, thermodynamic stability studies, freeze-thaw cycling, centrifugation tests, self-emulsification time analysis, cloud point determination, robustness to dilution, and Fourier Transform Infrared (FTIR) spectroscopy. In vitro drug release was evaluated using a USP Type II dissolution apparatus.
Results: Among the formulations, IT3 exhibited the highest stability and optimal self-emulsification, achieving complete dissolution in 180 minutes. Other formulations demonstrated drug release in 240 to 360 minutes, while the commercial Sporanox capsule released only 67% of the drug after 600 minutes. Thermodynamic studies confirmed that IT3 was the most stable, receiving an "excellent" rating, while IT4 and IT6 were classified as "good." Cloud point analysis showed stability up to 80°C, and robustness to dilution studies confirmed no phase separation even after 1000-fold dilution. FTIR spectroscopy confirmed compatibility between itraconazole and formulation excipients.
Conclusion: The optimized SNEDDS formulation significantly improved the solubility and dissolution rate of itraconazole, outperforming conventional dosage forms. The study highlights the potential of SNEDDS as an effective oral drug delivery strategy for poorly soluble drugs, providing a robust formulation approach for enhanced therapeutic efficacy.