bluuebunny/crossref_metadata_2025 huggingface dataset:
Demographic factors associated with awareness of patient safety among nurses in a public hospital in Makassar, Indonesia
Authors: Jahja Felicia , Tania Abigail , Bernarto Innocentius
Published: September 2024

Background: Despite being a global concern, patient safety remains a persistent challenge for Wahidin Sudirohusodo Hospital, evident in performance indicators like mortality rates, nosocomial infections, and hand hygiene practices. Numerous factors influence patient safety, including working hours, nurse awareness, and demographic characteristics.
Purpose: To investigate demographic factors associated with awareness of patient safety among nurses in a public hospital in Makassar, Indonesia.
Method: Cross-sectional analytical research, involving 291 nurses selected through simple random sampling from Wahidin Sudirohusodo Hospital Makassar, Indonesia. Nurses completed a questionnaire that included demographic data, patient safety awareness, and implementation. Analysis uses the smartPLS application which includes bivariate and multivariate logistic regression.
Results: Based on identification, it was found that total work hours for a single week (p=0.002) and nurses' awareness of patient safety (p=0.000) had a direct effect on implementation. Nurses who worked less than 40 hours per week showed twice the effectiveness, while nurses with high conscientiousness showed a fivefold increase in effectiveness. In contrast, age, education level, and years of service did not show a significant impact on implementation.
Conclusion: It highlights that beyond mere working hours, factors such as awareness towards patient safety, age, length of employment, and educational background significantly influence patient safety culture. While shorter total work hours for a single week and good patient safety awareness were found to increase patient safety culture; age, education levels, and length of employment demonstrated nuanced associations.
The effectiveness of cupping therapy and cucumber juice on blood pressure and total cholesterol levels among patients with hypertension
Authors: Kusrina Kusrina , Supriyadi Supriyadi , Pujiastuti Rr. Sri Endang
Published: September 2024

Background: Hypertension is a non-communicable disease that poses a growing public health concern, with its prevalence increasing annually. High levels of total cholesterol are a risk factor for hypertension because cholesterol can lead to plaque buildup in blood vessels. Over time, this plaque can thicken, harden the blood vessels, and cause blockages or atherosclerosis. Treatment and prevention of hypertension typically involve regular medication and routine health check-ups. In addition, non-medical therapies, such as a combination of cupping therapy and a high-fiber diet including cucumber juice consumption, can be employed.
Purpose: To determine the effectiveness of cupping therapy and cucumber juice in reducing blood pressure and total cholesterol levels in patients with hypertension.
Method: This quantitative study employed a quasi-experimental design using a pre-posttest control group design. The study involved 60 participants divided into four groups: the cupping therapy intervention group, the cucumber juice intervention group, the combined cupping therapy and cucumber juice group, and a control group that received the medications captopril 25 mg and simvastatin 10 mg.
Results: Administering cupping therapy three times a week and 150 ml of cucumber juice twice a week for 14 days effectively reduced the average systolic blood pressure from a pretest value of 153 mmHg to a posttest value of 125 mmHg (p = 0.004). The average diastolic blood pressure decreased from a pretest value of 90.6 mmHg to a posttest value of 77 mmHg (p = 0.083), and the average total cholesterol level dropped from a pretest value of 283 mg/dl to 188 mg/dl (p = 0.011).
Conclusion: Administering cupping therapy three times a week and cucumber juice twice a week for 14 days effectively reduces blood pressure and total cholesterol levels in patients with hypertension.
Stunting among children under 5 years of age in Surakarta City, Central Java
Authors: Dewi Indria Aulia , Arifah Siti
Published: September 2024

Background: Stunting is defined as the growth of a child below the expected level for his or her age. It can occur during pregnancy, breastfeeding, and up to the first 1000 days (about 2 and a half years) of life. Stunting affects the brain development of the children, physical-motor growth, and has long-term implications for their future. The causes of stunting in children are multifaceted and can range from long-term inadequate nutrition to genetic and psychosocial factors.
Purpose: To investigate demographics data of stunting among children under 5 years of age in Surakarta City, Central Java.
Method: A quantitative design and descriptive analytical approach were used. The data were collected from a population of stunted children in the work area of the Pajang Community Health Centre between November and December of 2023. The research used purposive sampling and involved 93 respondents. 
Results: Finding characteristics of both children and mothers with specifically, 71% of the stunted children were categorized as short, 52.7% were male, and the majority had a normal birth length. Most mothers of stunted children are aged between 20 and 35 years, 50.5% of mothers are taller than 155 cm (about 5.09 ft), 52.5% of mothers have a high school education and 74.2% of mothers are unemployed. 
Conclusion: The characteristics of children and mothers about stunting are complex and interrelated. Therefore, health service providers should provide the best interventions with particular attention to both community and family-centered care.
Soda consumption and overweight in high school students in Surakarta, Indonesia
Authors: Ramadhoni Farhan Dian , Mardiyati Nur Lathifah
Published: September 2024

Background: Adolescence is an age that is vulnerable to facing various nutritional problems, both malnutrition and excess nutrition. Excessive nutrition is a body condition where food intake exceeds the recommended daily requirements, causing fat accumulation. Overnutrition in adolescents can be seen through the Body Mass Index (BMI) according to age, where assessment results that exceed ≥+1 SD are included in the overnutrition category. Consumption of soft drinks is a risk factor that causes overnutrition due to excess sugar intake from these soda drinks. High intake of sweet drinks can increase overweight and can be a risk of metabolic disease. The recorded number of children and teenagers in Indonesia who were overweight or obese in 2018 was 20% or 7.6 million school children and 14.8% or 3.3 million teenagers.
Purpose: To determine the relationship between soda drink consumption and overweight.
Method: Observational research with a cross sectional approach. This research analyzes the relationship between the independent variable (frequency of soda consumption) and the dependent variable (more nutrients) which was carried out by collecting data at the same time. The population in this study were all tenth and eleventh grade students at SHS 1 Muhammadiyah, SHS 2 Muhammadiyah and Muhammadiyah Surakarta Special Program High School, with a sample of 104 respondents. The research was conducted at 3 Muhammadiyah High Schools in Surakarta on November 2022 – February 2024. Soda consumption data was collected using the Food Frequency Questionnaire (FFQ). Meanwhile, nutritional status data is carried out by anthropometric measurements such as height, weight and calculation of Body Mass Index (BMI) based on age (BMI/U).
Results: It was found that there was no significant relationship between soda drink consumption and the incidence of overnutrition with a p-value of 0.794.
Conclusion: There is no relationship between soda drink consumption and overnutrition.
Robotic-assisted range of motion therapy on limb muscle tone in chronic stroke patients: A systematic review
Authors: Nasim Nasim , Nani Desiyani , Triyanto Endang
Published: September 2024

Background: Stroke is a sudden neurological deficit that arises from vascular damage in the central nervous system, which can lead to disabilities, particularly affecting the movement capabilities of those impacted. While often associated with older adults, the occurrence of stroke in younger individuals has risen in recent years. The disabilities that result from strokes in younger adults can contribute to economic challenges and a reduced quality of life. To mitigate the functional limitations caused by stroke, interventions such as Robotic Range of Motion (ROM) can be utilized, taking advantage of technological advancements. Robotic ROM techniques can improve muscle tone in the limbs, and it is anticipated that consistent ROM interventions will effectively alleviate movement restrictions in these areas.Top of FormBottom of Form
Purpose: To identify robotic-assisted range of motion therapy on limb muscle tone in chronic stroke patients.
Method: A systematic review approach in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Articles were sourced from online databases such as PubMed, Google Scholar, and ProQuest. The review was organized according to the PICOS framework. In this article, the PICOS criteria were defined as follows: P: Stroke patients, I: Range of Motion (ROM) exercises using robotics, C: Inclusion of a control group, O: Improvement in muscle tone, S: Randomized Controlled Trial (RCT). The keywords used in the search included “range of motion,” “robotic intervention,” “muscular tone,” and “stroke patient.” Articles were selected based on specific inclusion criteria: publication within the last five years (2019-2024), English language, use of robotics in interventions, focus on stroke patients, application of randomized controlled trial research methods, and availability of the full text.
Results: The literature review of the five journals revealed that Robotic ROM interventions are effective in enhancing muscle tone in stroke patients. This conclusion is backed by clinical evidence gathered from the analysis of these journals.
Conclusion: Based on the analysis of the five articles, it is evident that ROM intervention utilizing robotics through various methods positively affects the extremities of stroke patients.
دراسة مقارنة بين اجهزة توقيت مختلفة لإنجاز سباق ١٠٠ متر حرة للعدائين تحت ٢٠ سنة
Authors: Al-Mustafa Subaih Hussein  , Prof. Dr. Ali Abdul Hassan Hussein
Published: September 2024

تطورت العملية التدريبية في الآونة الأخيرة حيث أصبح الاعتماد في التدريب على الأجهزة الحديثة المؤثرة في نوع الأداء فضلا عن الاعتماد على أساليب حديثة غير مألوفة سابقا"، لذلك يعد تدريب الرياضيين وتهيئتهم من الأمور المهمة والضرورية من اجل ارتقائهم لمستويات عالية من الإعداد البدني والمهاري مما يؤهلهم لخوض المسابقات بكفاءة عالية ، وعلى أساس ذلك تطورت الانجازات بتطور علم التدريب وتداخله مع العلوم الأخرى خدمة في تحقيق العملية التدريبية ، ومن الفعاليات التي شهدت تطويراً كبيراً في مجال العاب القوى هي فعالية 100م لما تتميز به هذه الفعالية في الأداء المركب وتعد فعاليات الركض السريع من أكثر فعاليات ألعاب القوى إثارة وتشويقاً لما فيها من منافسة قوية.
وتعد الدقة في توقيت الفعاليات الرياضية عنصراً أساسياً في تحديد الفائزين وتقييم الأداء الرياضي. منذ ظهور السباقات الرياضية، تم ابتكار العديد من الوسائل لضمان دقة التوقيت، بدءاً بالتوقيت اليدوي الذي يعتمد على رد فعل الإنسان، وصولاً إلى الأجهزة التكنولوجية المتقدمة مثل جهاز الفوتوفنش. تتطلب سباقات الركض دقة فائقة في قياس الزمن لضمان العدالة والدقة في النتائج، حيث يلعب التوقيت دورًا حاسمًا في تحديد الفائزين وتحقيق الأرقام القياسية. تتطلب مسابقات الركض دقة فائقة في تحديد الزمن لضمان العدالة في النتائج. تم في هذه الدراسة مقارنة دقة ثلاثة أنواع من الأجهزة المستخدمة في توقيت سباق 100 متر للشباب: جهاز مبتكر جديد، جهاز الفوتوفنش التقليدي، والتوقيت اليدوي.
وتكمن أهمية البحث في تصنيع جهاز توقيت مشابه لعمل جهاز الفوتوفنش من قبل الباحثان واجراء مقارنة في التوقيتات بين الاجهزة المختلفة المعتمدة في السباقات (جهاز الفوتوفنش، التوقيت اليدوي) بالإضافة الى الجهاز المبتكر من قبل الباحثان.
Розробка методики неруйнівного контролю пружин з використанням магнітного структурного аналізу
Authors: Шевченко О.В.
Published: September 2024

В статті досліджено взаємозв’язок між твердістю, залишковою деформацією під навантаженням та коерцитивною силою пружин підвіски рухомого складу залізничного транспорту. За результатами випробувань пружин на залишкову деформацію під навантаженням встановлено, що оптимальною структурою пружин є троостит відпуску. Саме структура трооститу відпуску забезпечує оптимальні пружні властивості пружинних сталей в умовах знакозмінних навантажень. Доведено, що для контролю якості пружин замість процедур вимірювання твердості та залишкової деформації можна використовувати процедуру вимірювання коерцитивної сили пружин. Коерцитивна сила, також як і твердість, є структурно чутливим параметром. Впровадження у виробничий процес магнітного структурного аналізу замість вимірювання твердості та випробувань пружин на залишкову деформацію дозволяє суттєвим чином спростити процедуру контролю якості пружин. Встановлено, що наявність на поверхні пружин зневуглецьованого шару практично ніяк не впливає на коерцитивну силу пружин, за умови, якщо товщина зневуглецьованого шару не перевищує значень, регламентованих діючим стандартом. Отже, певне, але не дуже суттєве зменшення коерцитивної сили пружин по відношенню до рекомендованих значень може свідчити про наявність на поверхні пружин зневуглецьованого шару понаднормової товщини. Наявність на поверхні пружин тріщин ніяк не впливає на їхню коерцитивну силу, незалежно від природи тріщин та механізмів їхнього утворення. Коерцитивна сила пружин залежить виключно від їхньої структури, яка визначається режимом термічної обробки. Доведено, що оптимальна твердість пружин та коерцитивна сила, що відповідає цій твердості, можуть бути встановлені лише за результатами попередніх випробувань пружин на залишкову деформацію під навантаженням. Саме залишкова деформація під навантаженням є основною експлуатаційною характеристикою пружин, який визначає можливість або неможливість їхнього використання в тих або інших умовах. Таким чином, результати досліджень дозволяють встановити взаємозв’язок між експлуатаційними характеристиками та структурою пружин і саме на основі цього взаємозв’язку розробити оптимальну методику неруйнівного контролю структури пружин в умовах серійного виробництва.
Electric drive with frequency-regulated synchronous motor with high precision digital sensors
Authors: Rudniev Y.S. , Romanchenko J.A. , Brozhko R.M.
Published: September 2024

The article studies an electric drive with a frequency-regulated synchronous motor.The main advantages of synchronous motors in comparison with asynchronous ones are listed.The current state and the growth trends in the production of AC electric drives are considered. It is shown that two-link frequency converters have received the greatest application for wide-range regulation of rotation frequency of synchronous motors.They convert the electricity from supply network into electricity with the required voltage, current and frequency in two stages.This transformation is carried out by special devices – autonomous inverters. It has been established that the efficiency of a two-link frequency converter is quite high and about 96,5-98,5%, which is due to the efficiency of the power semiconductor devices used in the key operating mode.Modern trends in the use of voltage and current inverters are considered. It is shown that the use of new semiconductor devices made it possible to fundamentally change the topology of the power circuit and the principles of inverter control. The approach of most manufacturers to the topology of autonomous inverters in frequency converters is considered. The most advanced structures (matrix and hybrid) of AC converters, which are produced by modern industry, are considered.Based on the analysis, it is set that high-precision, reliable and noise-resistant digital sensors are widely used in DC and AC electric drive systems – absolute and incremental encoders, as well as optoelectric attached sensors for registering distances, angles of rotation or the number of turns – resolvers. They are used together with numerical control systems, drives and position determination devices.The power supply circuit for synchronous electric motors of the main drive of the rolling stand of a thick plate mill 3000 based on ALPSA VDM 7000 converters from ALSTOM (Converteam) is considered. The main task of control system of the converter network part is to regulate the voltage of the DC link.The block diagram of the control system for the rectifier and inverter parts of the VD 7000 converters is given.
The place of the uranium industry and prospects for creating a growth pole in Niger
Authors: ABDO Hassan Maman
Published: September 2024

With the prospect of exploiting the Imouraren uranium deposits in the north of the country, this article looks at the contours of an industrialization strategy based on the creation of a growth pole in this part of the country. Firstly, the paper shows how the concept of a growth pole has evolved into that of a competitiveness pole. It then examines the dependence of the Niger economy on uranium mined by the two major French companies since the early 1970s. Drawing lessons from the unequal sharing of uranium rents and the nature of this mineral, it proposes the creation of a growth pole that could evolve into the establishment of a Niger cluster. The success of this industrial development strategy requires the involvement of all competent partners from both North and South in the field of uranium mining, sales, and purchases. Such a policy aims to reduce the economic and socio-political crises that affect the evolution of economic parameters. It can be generalized to put Niger's territories in competition with each other.
The Impact of CEO and CFO Gender on Family Firm Performance
Authors: Dezfouli Kaveh Moradi , Ravi Rahul
Published: September 2024

This study examines the impact of CEO and CFO gender on firm performance, with a focus on family firms. Family firms focus on strategic decision-making with a tendency to pass the firm to the next generations which includes the appointment of top executives. Since family firms are more likely to appoint a family member as CEO or CFO, common gender-based discriminatory practices play a lesser role in these decisions. Our results indicate that non-family firms with female CEOs or CFOs outperform those with male CEOs or CFOs. However, in contrast to non-family firms, the performance of family firms does not vary based on the gender of the CEO or CFO. This underscores the various discriminatory practices women face throughout the entirety of their careers, as female executives must demonstrate superior abilities to “shatter the glass ceiling” and attain top executive positions. Our study highlights the importance of addressing gender-based discriminatory practices at various stages of women's careers, rather than focusing solely on their tenure as top executives.
Exploring the Role of the Dutch East India Company in Making Taiwan a Center for the Sugar Trade From 1624 to 1662
Authors: Chang Chih-Hsiung , Shih Yi-Yu , Chang Wu-Hua , Chang Yung-Sheng
Published: September 2024

This article intends to explore the actual role of the Dutch East India Company during the Dutch colonial period from 1624 to 1662, when Taiwan became a sugar supply center and its trade status was upgraded from a trading relay station to a trading center for sugar trade with Eurasian markets. This article tests the established model and hypothesis through five dimensions. Except for the fourth dimension, the others all obtain support for the hypothesis. The research results found that whether it is from the improvement of Taiwan’s sugar supply and sugar trade status, or the booming period of the Dutch East India Company’s sugar trade and the two-stage rise in European sugar prices, in addition to marking changes in Taiwan’s industrial transformation and trade status, all of this highlights that the Dutch East India Company indeed played a pivotal role in Taiwan during this process.
SPOR BİLİMLERİ FAKÜLTESİNDE ÖĞRENİM GÖREN ÖĞRENCİLERİN SPORTMENLİK VE SPORA BAĞLILIK DÜZEYLERİ İNCELENMESİ
Authors: Köroğlu Mihraç , Çelik Nuri Muhammet , Yentürk Burcu , Soyer Fikret
Published: September 2024

Bu çalışmanın amacı, Batman Üniversitesi Spor Bilimleri Fakültesi'nde beden eğitimi ve spor öğretmenliği, spor yöneticiliği ve antrenörlük eğitimi alan öğrencilerin sportmenlik ve spora olan bağlılıklarını çeşitli değişkenler açısından incelemektir. Araştırmada ilişkisel tarama modeli kullanılmış ve Veriler Sportmenlik Ölçeği ile Spora Bağlılık ölçeği aracılığıyla elde edilmiştir. Bu çalışmanın evrenini Batman Üniversitesi Spor Bilimleri Fakültesinde eğitim almakta olan 1070 öğrenci oluşturmakta olup örneklem ise 565 katılımcıdan meydana gelmektedir. Araştırmaya katılacak öğrencilere sportmenlik ve spora bağlılık ölçekleri dağıtılarak elde edilen veriler SPSS programında analiz edilmiştir. Demografik özellikler için betimleyici istatistik uygulanmıştır. Verilerin analizi için değişken sayısı iki ise Mann-Whitney-U Testi, değişken sayısı ikiden fazla olanlar için Kruskal Wallis- H testi uygulanmıştır. Değişkenleri ikiden fazla gruplarda anlamlı fark olması durumunda farklılığın hangi gruplar arasında olduğunu anlamak için sıralı olarak Mann-Whitney-U Testi yapılmıştır. Analiz sonuçlarına bakıldığında katılımcıların sportmenlik düzeylerinin cinsiyet, yaş, yapılan spor branşı değişkenlerine göre anlamlı fark gösterirken, öğrencilerin okuduğu bölüm, sınıf, sporla uğraşma yılı ve spor yapma sıklığına göre anlamlı fark göstermediği görülmüştür. Katılımcıların spora bağlılık düzeylerinin ise öğrencilerin okuduğu bölüm, yapılan spor branşı, sporla uğraşma süresi ve spor yapma sıklığı değişkenlerine göre anlamlı farklılıklar göstermektedir. Spora bağlılık düzeyleri cinsiyet, yaş ve sınıf değişkenlerine göre ise anlamlı fark göstermemektedir.
Investigation of the influence of different rotor components on the axial impeller tip clearance at different operating points
Authors:   German Aerospace Center (DLR) Institute of Low Carbon Industrial Processes, Köhler Martino , Schaffrath Robert ,   German Aerospace Center (DLR) Institute of Low Carbon Industrial Processes, Lockan Michael ,   German Aerospace Center (DLR) Institute of Low Carbon Industrial Processes, Nicke Eberhard ,   German Aerospace Center (DLR) Institute of Low Carbon Industrial Processes
Published: September 2024

This work examines a radial turbo-compressor for a high-temperature heat pump (HTHP) with steam as the working medium. The given boundary conditions result in very small blade heights for the impellers. It is therefore necessary to minimize the gap between the impeller and housing in order to ensure the lowest possible gap flow. It is to be expected that even small deviations towards a larger gap have a major negative impact on the performance of the compressor. Nevertheless, a collision must also be avoided. In order to find efficient and reliable impeller designs an automated optimization is performed considering aerodynamic as well structural aspects (Schaffrath et al., 2022). However, the optimal impeller design represents the so-called hot geometry under operating conditions, for the manufacturing process this geometry have to be transformed into the so-called cold geometry (Schaffrath et al., 2023). Due to the necessary quality of detail in the gap maintenance, the question arises as to whether it is sufficient to execute the hot-to-cold transformation exclusively on the impeller and whether there is a significant influence of the other components of the rotating system. The FE simulation is used to compare the maximum axial deformation values between the design of the single impeller and the entire rotating system. The result shows a deviation in axial deformation of more than 50% compared to the result of the ”hot-to-cold transformation” (H2C) used in optimization process chain. This shows that the single impeller calculation is not sufficient to precisely achieve the gap on which the CFD design is based.
Effect of protrusions and leading edge ribs on the local heat transfer characteristics in a two-pass cooling channel under rotation
Authors:   Institute of Aerospace Thermodynamics University of Stuttgart, Gutiérrez de Arcos David , Waidmann Christian ,   Institute of Aerospace Thermodynamics University of Stuttgart, Poser Rico ,   Institute of Aerospace Thermodynamics University of Stuttgart, von Wolfersdorf Jens ,   Institute of Aerospace Thermodynamics University of Stuttgart, Jäppelt Bernhard ,   MTU Aero Engines AG, Semmler Klaus ,   MTU Aero Engines AG
Published: September 2024

Optimised internal cooling schemes for turbine blades aim at enhancing the heat transfer between the hot channel walls and the relatively cold fluid while preventing overcooling. Often, a combination of different turbulator types adapted to the specific turbine blade application are required. Prior research has demonstrated that a promising design featuring high heat transfer in exchange for a reasonable pressure loss penalty is achieved through the use of ribs and protrusions. As regards to rotor blades, rotation represents a key factor with a pronounced impact on the secondary flow field, and thus on the heat transfer characteristics. In the present work, local heat transfer measurements using the transient thermochromic liquid crystal (TLC) technique are conducted under engine-similar test conditions in the rotating rig of the Institute of Aerospace Thermodynamics (ITLR) at the University of Stuttgart. A two-pass cooling channel channel with two different turbulator designs is investigated: a ribbed geometry (baseline) and a rib-protrusion geometry with leading edge ribs (enhanced). Additionally, numerical simulations performed with ANSYS CFX support the experimental approach and complement it with flow field visualisations. It is shown that the rib-protrusion compound is able to improve the heat transfer under both rotating and non-rotating conditions. Nevertheless, a strong reduction in heat transfer caused by rotation occurs with the rib-protrusion geometry, especially considering the radially inward flow of the second passage. The importance of rotation on the secondary flow field and thereby on the internal heat transfer is demonstrated, contributing to a better understanding of cooling air usage under engine-realistic test conditions.
Study of Actuators and Injectors for Tip Air Injection in the Axial Compressor of the Larzac 04 Jet Engine
Authors:   University of the Bundeswehr Munich, Institute of Jet Propulsion, Schäfer Yannik , Stößel Marcel ,   University of the Bundeswehr Munich, Institute of Jet Propulsion, Kozulovic Dragan ,   University of the Bundeswehr Munich, Institute of Jet Propulsion
Published: September 2024

In order to study active flow control in axial compressors where first stage stalls first, a new inlet system with 17 piezoelectric actuators for tip air injection was designed and built for the application on the Larzac 04 jet engine at the Institute of Jet Propulsion at the University of the Bundeswehr Munich. Before starting the experimental investigations on the jet engine, preliminary studies of the key components (actuators and injectors) were conducted on 4 different operating points, which are presented in this paper. This includes a description of the experimental test setup, which corresponds to a circular section of the Larzac inlet. A hot-wire anemometer is installed at a distance from the future rotor plane to investigate the individual actuator and injector components. With the information about the velocity in the rotor plane, the dimensions of the injected air mass flow are displayed with static contour plots. These are used to show and discuss the potential of the injected jet with respect to the excess velocity and the injection power, which are important parameters for the expected stall margin improvement of an engine application. This shows large potential for increasing the velocity by a factor of up to 3 in the tip region of low pressure compressor, at operating points in the low speed range. Due to the fast response of the system, pulsed injection up to 200 Hz is also possible. It is shown that pulsed injection between 0 Hz and 200 Hz does not cause any unwanted resonances and is therefore suitable for subsequent operation in the engine.
Liquid Hydrogen and Synthetic Sustainable Aviation Fuel: A European Airline Case Study
Authors:   Trinity College Dublin, Gallagher Conor , Stuart Charles ,   Trinity College Dublin, Spence Stephen ,   Trinity College Dublin
Published: September 2024

There is much debate surrounding Liquid Hydrogen (LH2) and Sustainable Aviation Fuel (SAF) across the aviation industry in terms of future fuel applications for decarbonisation. This study aims to quantify the real-world energy performance of LH2 and SAF powered aircraft in order to determine the optimum energy carrier for short-haul operations. An operational case study was performed comparing the energy performance of LH2 and SAF-powered aircraft, through the evaluation of each configuration over a complete day of airline flights to and from the island of Ireland using a novel real-world operations simulation framework. Aircraft models were developed for the B737-800NG and B737-8200 aircraft using physics-based and semi-empirical methods, which were validated, and subsequently calibrated against a broad range of real-world flight data, yielding average total fuel burn errors of 1.6% against 50 test data flights for both aircraft models. Using the calibrated models, three equivalent LH2-powered aircraft models were designed with varying LH2 tank gravimetric indices, along with an intercooled-recuperated LH2 configuration. Each aircraft configuration was simulated over a full day of operations, where the fleet-wide well-to-wake energy consumption and the renewable electricity cost was compared for each LH2 aircraft and three SAF candidates, produced using direct air capture, alcohol-to-jet, and Fischer- Tropsch processes. Despite decreased in-flight energy performance, the LH2 aircraft yielded lower well-to-wake energy consumption in almost all cases, where the direct air capture method for SAF was found to be at least 44% more energy intenstive than LH2, which may be a deterrent for future fuel applications despite challenges with LH2 infrastructure and aircraft design. Low-carbon ASTM-approved SAF pathways using biogenic feedstocks yielded maximum energy penalties between 14% – 27% compared to the LH2 configurations. The intercooled-recuperated LH2 engine resulted in a fleet-wide energy reduction of 4.4%, increasing the viability of LH2 aircraft against kerosene and SAF-powered aircraft.
Improved modelling of the turbulent heat flux for film cooling applications in RANS with a machine learned turbulent thermal diffusivity distribution
Authors:   Technical University of Darmstadt, Goertz Florian , Janetzke Timm ,   Rolls-Royce Deutschland Ltd. & Co. KG, Schiffer Heinz-Peter ,   Technical University of Darmstadt
Published: September 2024

To increase the thermodynamic efficiency of aero engines and gas turbines, the turbine entry temperature is increased far above the melting temperature of turbine blade materials. Therefore, the cooling of the high pressure turbine is of great importance. In the high pressure turbine, film cooling is extensively used. For the design of the cooling system an accurate prediction of the blade temperature distribution is necessary. The widely used RANS simulations show significant shortcomings in predicting an accurate temperature distribution in turbulent flows, especially when it comes to the mixing of cooling films with the main flow. In this study a comparison of the film cooling effectiveness prediction between RANS and LES is presented for a film cooled flat plate to quantify the shortcomings of RANS. The results from LES are then used to train a machine learning model for the turbulent thermal diffusivity to improve the turbulent heat flux prediction in RANS. With the machine learned turbulent thermal diffusivity, the RANS simulation predicts a similar temperature distribution to LES simulations. The model is then applied to an engine realistic film cooled turbine blade.
The Ability of Anisotropic Mesh Adaptation to Capture Complex Physics on a Transonic Tandem Compressor
Authors:   GammaO, Equipe Inria-ONERA - Centre Inria de Saclay, Guilbert Éloi , Remigi Alberto ,   Safran Tech, Modelling and Simulation, Alauzet Fréderic ,   GammaO, Equipe Inria-ONERA - Centre Inria de Saclay, Philit Mickael ,   Safran Tech, Modelling and Simulation
Published: September 2024

This paper shows the ability of metric-based anisotropic mesh adaptation to accurately capture flow features on a common complex test case the TUDa-GLR-OpenStage : a transonic compressor with variable stator vane in tandem arrangement. This case involves several rows interaction, it has one rotor, one stator and one outlet guided vane (OGV). Two aspects have to be taken into account to extend mesh adaptation for such multi-row configurations. First, the rotor-stator and the stator-OGV interactions are modeled with mixing plane boundary condition technique as it removes the dependency of the results on the relative position between the rotor and the stator, and allows the use of steady simulation. A new mixing plane numerical scheme is developed to deal with unstructured meshes. Secondly, the mesh adaptation error estimate is extended to equidistribute the error over all the rows of the machine to achieve a consistent mesh adaptation process. The proposed methodology is validated on the TUDa-GLR-OpenStage for which a detailed numerical analysis is given.
PENGARUH KEPEMILIKAN INSTITUSIONAL DAN LEVERAGE TERHADAP KINERJA KEUANGAN (STUDI KASUS PERUSAHAAN MANUFAKTUR YANG TERDAFTAR DI BURSA EFEK INDONESIA)
Authors: Nur Cahyati Sitti , Wawo Andi Basru , Labangu Yuli Lestari
Published: September 2024

Penelitian ini bertujuan untuk menguji dan menganalisis pengaruh kepemilikan institusional dan leverage terhadap kinerja keuangan perusahaan manufaktur yang terdaftar di Bursa Efek Indonesia tahun 2018-2022. Jenis penelitian ini adalah penelitian kuantitatif. Analisis yang digunakan adalah analisis regresi data panel. Alat analisis yang digunakan untuk meregresi data panel adalah E-Views 12. Populasi dalam penelitian ini adalah perusahaan manufaktur sektor bahan dasar yang terdaftar di Bursa Efek Indonesia sebanyak 78 perusahaan. Adapun jumlah sampel sebanyak 14 perusahaan dengan menggunakan teknik purposive sampling. Hasil Penelitian menunjukan bahwa kepemilikan institusional dan leverage berpengaruh terhadap kinerja keuangan perusahaan manufaktur yang terdaftar di Bursa Efek Indonesia tahun 2018-2022. Artinya, Dengan adanya kepemilikan oleh institusi yang besar akan mendorong peningkatan pengawasan yang lebih optimal dalam memonitoring manajemen, tentunya akan menjamin kemakmuran untuk pemegang saham, dan juga dalam menggunakan utang sebagai sumber pendanaan, perusahaan mampu dalam menangani resiko yang timbul dari penggunaan utang. Dengan adanya kemampuan tersebut, perusahaan dapat memaksimalkan peran utang untuk menghasilkan profitabilitas.
Dual-responsive nanoplatform for integrated cancer diagnosis and therapy: Unleashing the power of tumor microenvironment
Authors: Ma Rui , Zhang Peng , Chen Xiuying , Zhang Mengdi , Han Qinghe , Yuan Qinghai
Published: September 2024

Chemodynamic therapy (CDT), designed to trigger a tumor-specific hydrogen peroxide (H2O2) reaction generating highly toxic hydroxyl radicals (·OH), has been investigated for cancer treatment. Unfortunately, the limited Fenton or Fenton-like reaction rate and the significant impact of excessive reducing glutathione (GSH) in the tumor microenvironment (TME) have severely compromised the effectiveness of CDT. To address this issue, we designed a dual-responsive nanoplatform utilizing a metal-polyphenol network (MPN) -coated multi-caged IrOx for efficient anti-tumor therapy in response to the acidic TME and intracellular excess of GSH, in which MPN composed of Fe3+ and tannic acid (TA). Initially, the acidic TME and intracellular excess of GSH lead to the degradation of the MPN shell, resulting in the release of Fe3+ and exposure of the IrOx core, facilitating the efficient dual-pathway CDT. Subsequently, the nanoplatform can mitigate the attenuation of CDT by consuming the excessive GSH within the tumor. Finally, the multi-caged structure of IrOx is advantageous for effectively implementing photothermal therapy (PTT) in coordination with CDT, further enhancing the therapeutic efficacy of tumors. Moreover, the outstanding Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) (T1/T2) multimodal imaging capabilities of IrOx@MPN enable early diagnosis and timely treatment. This work provides a typical example of the construction of a novel multifunctional platform for dual-responsive treatment of tumors.
White blood cell counts can predict 4-year cardiovascular disease risk in patients with stable coronary heart disease: a prospective cohort study
Authors: Jiang Wencai , Huang Gang , Du Jinfeng , Yang Hanxuan , Zhou Shiheng , Dai Dayin , Tang Kai , Fang Lingxiao , Wang Xiao , Deng Xuejun
Published: September 2024

Background

The prevalence of cardiovascular disease has increased sharply in the Asian population, and evaluation of the risk of cardiovascular events with stable coronary heart disease remains challenging. The role of white blood cell (WBC) count in assisting clinical decision-making in this setting is still unclear.

Objectives

This study sought to evaluate the prognostic meaning of WBC count among patients with stable coronary heart disease.

Methods

This study included Asian participants (n = 1,933) from the prospective STABILITY (Stabilization of Atherosclerotic Plaque by Initiation of Darapladib Therapy) trial, which involved 15,828 patients with stable coronary heart disease with 3–5 years of follow-up on optimal secondary preventive treatment. WBC count was measured at baseline. Associations between WBC count and cardiovascular outcomes were evaluated by Cox regression analyses with multivariable adjustments. Hematologic emergencies in patients may introduce potential bias.

Results

In the lower WBC count quartiles, patients had lower-risk clinical profiles. Higher WBC counts were associated with greater event probabilities for cardiovascular death, major cardiovascular events, or all-cause death. In Cox regression models, WBC counts were an independent predictor of major adverse cardiovascular events (OR = 2.445, 95% CI 1.427–4.190, P = 0.001) for the primary outcomes. For the secondary outcomes, including the composite of all-cause death, cardiovascular death, myocardial infarction, stroke, and hospitalization for heart failure, WBC counts were significantly predictive of events with similar magnitude (OR = 1.716, 95% CI 1.169–2.521, P = 0.006).

Conclusions

In patients with stable coronary heart disease, higher WBC counts were associated with a heightened risk for the primary or secondary outcomes.

Registration

https://clinicaltrials.gov/; Unique identifier NCT00799903.
Surmounting the summit: tackling cerebral malperfusion in AMDS-treated acute deBakey I dissections. A case report
Authors: de Manna Nunzio Davide , Helms Florian , Deniz Ezin , Kaireit Till Frederik , Abu-Fares Omar , Schmack Bastian , Ruhparwar Arjang , Weymann Alexander , Popov Aron Frederik
Published: September 2024

Background

Acute Type A aortic dissection (ATAAD) with supra-aortic branch (SAB) malperfusion remains a formidable clinical challenge, often resulting in high mortality and complex treatment dilemmas. The introduction of the AMDS represents a significant innovation, designed to stabilize the aortic arch, and manage malperfusion effectively.

Methods

This case study evaluates the utility of AMDS in the treatment of a 63-year-old male with hypertension, who presented with severe, acute chest pain. Diagnosed with a DeBakey type I ATAAD involving SAB, the patient underwent cardiopulmonary bypass, aortic root replacement, aortic arch repair with AMDS implantation, and subsequent endovascular stenting for severe left common carotid artery malperfusion that developed postoperatively. The AMDS was instrumental in facilitating crucial aortic arch reconstruction and addressing the initial severe malperfusion. Despite postoperative cerebral malperfusion, targeted endovascular stenting resulted in a rapid and substantial neurological recovery. The patient was discharged to a rehabilitation facility on postoperative day 20, free of neurological deficits.

Conclusions

The use of AMDS in managing ATAAD with SAB involvement is transformative, enabling less invasive surgical techniques and offering immediate, effective correction of malperfusion. This case underscores the essential role of integrating advanced endovascular strategies to enhance outcomes in high-risk aortic surgeries, marking a pivotal advancement in the therapeutic approach to complex aortic dissections.
Higher serum phosphate within the normal range is associated with the development of calcified aortic valve disease
Authors: Kim Kyung An , Jung Hae-Ok , Kim Mi-Jeong , Lee So-Young , Ahn Yuran , Jung Mi-Hyang , Chung Woo-Baek , Lee Dong-Hyeon , Youn Ho-Joong , Chang Hyuk-Jae
Published: September 2024

Background

Despite the essential role of ectopic osteogenic calcium-phosphate metabolism in the development of calcific aortic valve disease (CAVD), the implications of high serum phosphate levels in CAVD development are not fully understood.

Methods

Asymptomatic individuals who underwent health screening using serial cardiac computed tomography (CT) and echocardiography were selected from a multicenter registry. CAVD was identified and quantified on CT images using the aortic valve calcification (AVC) score. The associations between initial serum phosphate levels and the presence of baseline CAVD, development of new CAVD, and the AVC score progression rate were investigated using multivariable regression models.

Results

A total of 736 individuals were selected for analysis, and the median interscan duration was 36.4 months. On initial CT, 83 (13.7%) participants had baseline CAVD, while 52 (7.0%) individuals developed new CAVD during follow-up. Serum phosphate levels were not associated with a higher probability of baseline CAVD but were predictive of newly developed CAVD (odds ratio per 1 mg/dl, 1.05; 95% confidence interval, 1.01–1.10; p = 0.02). Higher phosphate levels were also associated with a faster AVC score progression in those with baseline CAVD (regression coefficient per 1 mg/dl, 15.55 Agatston units/year; 95% confidence interval, 6.02–25.07; p < 0.01), an association which remained significant when the analysis was extended to include newly developed CAVD.

Conclusion

Even slight elevations in serum phosphate are associated with accelerated CAVD progression from an early stage. Further studies are needed to investigate whether the regulation of phosphate metabolism can slow the progression of CAVD to aortic stenosis.
Robust-momentum-learning-rate-based adaptive fractional-order least mean squares approach for power system frequency estimation using chaotic Harris hawks optimization
Authors: Pati Subhranshu Sekhar , Subudhi Umamani
Published: September 2024

A novel robust adaptive technique is proposed to estimate the instantaneous power system frequency using a momentum-learning-control-rate-based fractional-order least mean squares approach with enhanced Harris hawks optimization. The adaptive estimation comprises two modules, where the first part involves the design of the momentum-learning-control-term-based fractional-order least mean squares algorithm and second part focuses on parameter tuning of the algorithm through enhanced Harris hawks optimization incorporating chaotic mapping and opposition-based learning. This integration yields a robust and automated adaptive algorithm for frequency estimation with superior performance compared to traditional transform-based techniques, particularly in the presence of noise. The proposed method excels in scenarios where the estimator should manage multiple variables, including step size, fractional-order step constants, and momentum learning control terms. Moreover, it facilitates accurate power frequency estimation for real signals in multiarea power systems or microgrids. To validate the efficacy of the algorithm, computer-simulated data representing step and ramp changes in the frequency were processed. Additionally, the algorithm was tested with signals derived from a multiple-control-area, multisource renewable-based power system. Detailed comparative results were obtained and verified through MATLAB simulations and real-time experimental setup, demonstrating the superior performance of the adaptive model.
Superparamagnetically modified A-type, X-type and CHA-type zeolites with silica-coated Fe3O4 and CoFe2O4 nanoparticles for removal of Sr2+ and Cs+ from radioactively contaminated water
Authors: Ito Azusa , Thirunavukkarasu Gnanavel , Hriljac Joseph A.
Published: September 2024

Magnetised zeolite A, zeolite X and Na,K-CHA composites with superparamagnetic nanoparticles of SiO2-coated Fe3O4 or CoFe2O4 ferrite spinels were prepared, characterised and tested for ion exchange efficacy. They were synthesised by following three steps, synthesising Fe3O4 and CoFe2O4 nanoparticles by a solvothermal method, coating the metal oxide particles with SiO2 by a sol-gel process, and attaching the MxOy/SiO2 onto the zeolites during synthesis. The magnetic zeolites were characterised by X-ray diffraction, X-ray fluorescence spectroscopy, Raman spectroscopy, vibrating sample magnetometry and both scanning and transmission electron microscopy. It was confirmed they had superparamagnetic properties due to successful attachment of the MxOy/SiO2 particles onto the zeolites. Adsorption capacities of Sr2+ onto the magnetic zeolite A and zeolite X and Cs+ onto the magnetic Na,K-CHA were also evaluated. The results show the MxOy/SiO2 did not block the adsorption sites of the zeolites and the MxOy/SiO2 particles were not detached from the zeolites during the adsorption experiments.
From melting ice to green shipping: navigating emission reduction challenges in Arctic shipping in the context of climate change
Authors: Liu Huirong , Mao Zhengkai , Zhang Zhijun
Published: September 2024

The effects of global climate change have accelerated the melting of glaciers and the decline of sea ice coverage in the Arctic. In tandem with advancements in icebreaker and other shipping technologies, the navigability of Arctic shipping routes has dramatically improved. Given the geographical advantages of the Arctic region in terms of shipping routes and resource potential, various countries have implemented initiatives to secure a foothold in the Arctic shipping industry. However, the current shipping industry has not yet achieved the ideal state of net-zero emissions, and the rapid increase in Arctic shipping has brought serious and even irreversible negative impacts on the Arctic environment. The study employs document and policy analyses to conduct an in-depth examination of legal and policy documents related to Arctic shipping, especially those from the past 5 years, systematically outlining the relevant legal and policy frameworks, as well as their historical context. At the same time, interdisciplinary research methods are utilized to comprehensively assess the new challenges. It is concluded that against the backdrop of the Arctic region’s unique and fragile environment, the International Maritime Organization (IMO) and the Arctic Council are introducing increasingly stringent regulations for Arctic shipping, posing a complex array of challenges for the industry. Not only must it navigate the mounting pressure of emission reduction policies and intensifying public scrutiny but it must also overcome a multitude of complex technical and operational hurdles. Consequently, the joint efforts of the international community are essential to promote the sustainable development and emission reduction goals of the Arctic shipping industry.