bluuebunny/crossref_metadata_2025 huggingface dataset:
Associations Between Race and Socioeconomic Status, Lower Extremity Strength, and Patient-Reported Outcomes Following Anterior Cruciate Ligament Reconstruction
Authors: Prinz Nick W. , Thompson Xavier D. , Leicht Amelia S. Bruce , Kuenze Chris , Hart Joe M.
Published: June 2024

Context

There are significant disparities in access to health care, but there are limited data about the impact of race and socioeconomic status on postoperative outcomes following anterior cruciate ligament reconstruction (ACLR) surgery.

Objective

To identify associations between the Area Deprivation Index (ADI), strength measures, and patient-reported outcomes following ACLR and examine differences in outcomes between race, sex, and socioeconomic status.

Design

Case-control study in a single hospital setting.

Setting

Database secondary analysis.

Patients or Other Participants

Data were collected from 340 patients who underwent primary, isolated, unilateral ACLR.

Main Outcome Measure(s)

Strength measures and patient-reported outcomes were obtained at patients’ postoperative assessments at approximately 6 months postsurgery. Area Deprivation Index values were calculated on each patient’s census tract, as determined through medical records review. Correlations were conducted to determine the relationship between the ADI and Knee Injury and Osteoarthritis Outcome Score measures, International Knee Documentation Committee, and limb symmetry on strength measurements. The racial composition of the sample was heavily skewed and was excluded from statistical analyses.

Results

The ADI was weakly correlated with International Knee Documentation Committee (ρ = 0.11, P = .04) outcomes, with more disadvantaged patients reporting better quality of life and knee function. The ADI was not correlated with other outcomes of interest. The median ADI value of the sample was 32 (range, 1–86 [interquartile range, 19–47]).

Conclusions

Our study revealed a weak correlation between higher levels of socioeconomic disadvantage as measured by the ADI and improved subjective assessment of knee function and quality of life as measured by International Knee Documentation Committee. These findings are contrary to what other studies on this subject have found and highlight the importance of further research into the impact of socioeconomic status and other social determinants of health on post-ACLR outcomes.
Assessing the Diagnostic Impact of p53, p16, Retinoblastoma and bcl-2 Proteins in Human Papillomavirus-associated Squamous Cell Carcinoma of the Cervix
Authors: Aremu Adegoke Olalekan , Ekundina Victor Olukayode , Enye Linus Anderson , Kehinde Adedapo Olajide , Ogunlayi Aderonke Cecilia
Published: June 2024

BACKGROUND:

Cervical cancer is the third-most prevalent disease among women and is mostly associated with the human papillomavirus with a significant number of mortalities. It accounts for more than 95% of cases diagnosed late. The aim of the study was to investigate the involvement of tumor protein 53 (P53), tumor suppressor protein 16 (P16), retinoblastoma (Rb), and B-cell lymphoma 2 (BCL-2) as diagnostic factors in tumor suppression in cervical lesions. A case–control study that used 160 cervical tissue blocks selected from the pathology archives. All blocks used are confirmed cases of cervical samples.

METHODS:

Hematoxylin and eosin staining and immunohistochemical technique were used to treat samples with the matching antibodies for P53, P16, Rb, and BCL-2 expression as described by Camacho-Urkaray. Analysis of the data obtained from the study was carried out using photomicrographs, charts, graphs, and tables.

RESULTS:

A positive association between the expression levels of P53, P16, Rb, and BCL-2 with the progression of cervical lesions. It was revealed that P53 had a higher diagnostic effect for squamous cell carcinoma of the cervix, followed by P16, Rb, and BCL-2, respectively.

CONCLUSION:

The research shows that the P53, P16, Rb, and BCL-2 proteins are expressed in malignant lesions with moderate-to-severe intensities accordingly and are also closely related to the progression of cervical oncogenesis.
Recent Trends of Antibiotic Resistance Patterns of Gram-negative Bacteria Collected from Clinical Isolates in Dhaka City
Authors: Shama Anika Islam , Sultana Raquiba , Ferdous Mehjabin , Alam Seemi Tasnim , Momo Maisha Farzana , Mehjabin Tanaj , Ferdous Khaleda , Snikdho M. Saifuddin Nury , Pranto Abdullah Al Hasan , Uddin Md. Aftab
Published: June 2024

BACKGROUND:

Gram-negative bacteria responsible for a significant rise in antimicrobial resistance over the past 20 years. This alarming resistance has been linked to increased mortality and health-care costs, particularly for patients, clinicians, and the health-care system. Gram-negative bacteria cause a wide range of infectious diseases including gastrointestinal tract infections, urinary tract infections, respiratory tract infections, meningitis, typhoid fever, shigellosis, bacteremia, and septicemia.

METHODS:

A total of 220 different clinical specimens were collected between October 2022 and November 2023 from various renowned diagnostic centers of Dhaka, Bangladesh. According to the study plan, 199 Gram-negative bacterial isolates were collected, transported, and processed in the Microbiology Laboratory of Stamford University Bangladesh.

RESULTS:

The study found that female patients were predominant than male patients except for the Proteus cases. Escherichia coli was highly resistant to various antibiotics, with resistance levels ranging from 100% to 66%, although colistin was found effective. Azithromycin was the most ineffective antibiotic against Klebsiella, with 100% resistance. Other antibiotics showed high resistance, although colistin and imipenem showed effective sensitivity. High resistance levels were observed in azithromycin, colistin, doxycycline, nalidixic acid, co-trimoxazole, nitrofurantoin, cefuroxime, and amoxyclave for Proteus-infected patients, although some antibiotics showed effective sensitivity. However, Acinetobacter isolates were also found with high resistance levels across all age groups. For Pseudomonas cases, amoxyclav, nitrofurantoin, and cotrimoxazole were the most ineffective antibiotics, but colistin, ceftazidime, piperacillin, meropenem, and amikacin showed satisfactory efficacy.

CONCLUSION:

The study reveals alarming multidrug resistance in Gram-negative bacteria in Dhaka, raising public health concerns. Age and gender should be considered when selecting antibiotics.
Access to dental care and caries experience among children with cerebral palsy: a Singapore experience
Authors: Tan Joanne Mui Ching , Boo Yebeen Ysabelle , Manikam Logan , Yeo Tong Hong , Lin Jeremy Bingyuan , Yee Ruixiang , Ng Zhi Min
Published: June 2024

Introduction:

Cerebral palsy (CP) is one of the most severe childhood neurodevelopmental disabilities resulting from non-progressive insult to the developing brain. We aimed to report our experience regarding dental visit attendance, caries prevalence and factors affecting dental access in children with CP in Singapore.

Methods:

Patients diagnosed with CP who were born in or after 1994 were included in this study. We reviewed the data of all 151 patients recruited under the CP Registry in Singapore (SingCPR) from September 2017 to May 2020. The SingCPR was launched in September 2017 to assist in future planning of services and resources for CP in Singapore.

Results:

The mean age of the patients was 7.8 years, with the interquartile range being 3 years and 8 months–10 years and 10 months. Only 41.7% reported a visit to the dentist ever, with 25.4% reporting presence of dental caries. Age was the only statistically significant factor influencing access to dental care. None of the children less than 2 years old ever received any dental care, and 20% of the children with CP aged 2–6 years had received dental care before. Age range with the highest percentage of dental visits was 7–12 years, with up to 44.0% having ever received dental care. We believe the prevalence of dental caries was underreported as many children did not receive any dental care and therefore may have undetected dental caries.

Conclusion:

Dental care in children with CP should be advocated early for prevention and detection of caries.
Report from the EMS Executive Committee online meeting, 17–20 November 2023
Authors: Elwes Richard
Published: June 2024

The EMS Executive Committee (EC) holds two major meetings in each (non-exceptional) year, plus regular shorter virtual meetings. For reasons of environmental and financial sustainability, one of
the major meetings is now also held virtually. So, the EC plus guests met online between 17 and 20 November 2023.
Criterion for the existence of a connected characteristic space of orbits in a gradient-like diffeomorphism of a surface
Authors: Nozdrinova Elena Vyacheslavovna , Pochinka Olga Vital'evna , Tsaplina Ekaterina Vadimovna
Published: June 2024

The classical approach to the study of dynamical systems consists
in representing the dynamics of the system in the "source-sink" form,
that is, by singling out a dual attractor-repeller pair, consisting of
the attracting and repelling sets for all other trajectories
of the system. A choice of an attractor-repeller dual pair
so that the space of orbits in their complement (the characteristic space
of orbits) is connected paves the way for finding complete
topological invariants of the dynamical system. In this way, in particular,
several classification results for Morse-Smale systems were obtained.
Thus, a complete topological classification of Morse-Smale
3-diffeomorphisms is essentially based on the existence of a connected
characteristic space of orbits associated with the choice of
a one-dimensional dual attractor-repeller pair.
For Morse-Smale diffeomorphisms with heteroclinic points on surfaces,
there are examples in which the characteristic spaces of orbits are disconnected in all cases.
In this paper, we prove a criterion for the existence of a connected
characteristic space of orbits for gradient-like (without heteroclinic
points) diffeomorphisms on surfaces. This result implies, in particular,
that any orientation-preserving diffeomorphism admits a connected
characteristic space. For an orientable surface of any kind,
we also construct an orientation-changing gradient-like diffeomorphism that does not have
a connected characteristic space. On any non-orientable surface of any kind, we also construct
a gradient-like diffeomorphism which does not admit a connected characteristic space.
In-hospital outcomes in COVID-19 patients with non-alcoholic fatty liver disease by severity of obesity: Insights from national inpatient sample 2020
Authors: Srikanth Sashwath , Garg Vibhor , Subramanian Lakshmi , Verma Jyoti , Sharma Hansika , Klair Harroop Singh , Kavathia Shrenil A , Teja Jithin Kolli , Vasireddy Nikhil Sai , Anmol Kumar , Kolli Dhanush , Bodhankar Shruti Sanjay , Hashmi Sobya , Chauhan Shaylika , Desai Rupak
Published: June 2024

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) increases the risk of cardiovascular diseases independently of other risk factors. However, data on its effect on cardiovascular outcomes in coronavirus disease 2019 (COVID-19) hospitalizations with varied obesity levels is scarce. Clinical management and patient care depend on understanding COVID-19 admission results in NAFLD patients with varying obesity levels.

AIM

To study the in-hospital outcomes in COVID-19 patients with NAFLD by severity of obesity.

METHODS

COVID-19 hospitalizations with NAFLD were identified using International Classification of Disease -10 CM codes in the 2020 National Inpatient Sample database. Overweight and Obesity Classes I, II, and III (body mass index 30–40) were compared. Major adverse cardiac and cerebrovascular events (MACCE) (all-cause mortality, acute myocardial infarction, cardiac arrest, and stroke) were compared between groups. Multivariable regression analyses adjusted for sociodemographic, hospitalization features, and comorbidities.

RESULTS

Our analysis comprised 13260 hospitalizations, 7.3% of which were overweight, 24.3% Class I, 24.1% Class II, and 44.3% Class III. Class III obesity includes younger patients, blacks, females, diabetics, and hypertensive patients. On multivariable logistic analysis, Class III obese patients had higher risks of MACCE, inpatient mortality, and respiratory failure than Class I obese patients. Class II obesity showed increased risks of MACCE, inpatient mortality, and respiratory failure than Class I, but not significantly. All obesity classes had non-significant risks of MACCE, inpatient mortality, and respiratory failure compared to the overweight group.

CONCLUSION

Class III obese NAFLD COVID-19 patients had a greater risk of adverse outcomes than class I. Using the overweight group as the reference, unfavorable outcomes were not significantly different. Morbid obesity had a greater risk of MACCE regardless of the referent group (overweight or Class I obese) compared to overweight NAFLD patients admitted with COVID-19.
15 Combustion Characteristics of an Improved Design of a Stratified Charge Spark Ignition Engine
Authors: BARBATO Maurizio C. , HASSANEEN Ahmed E.
Published: June 2024

The characteristics of the combustion process in an improved design of a novel spark ignition engine studied by means of Computational Fluid Dynamics are presented. The engine is designed to work at low average combustion temperatures to achieve very low NOx emissions.

The engine is a two-stroke, two piston in-line engine. The main combustion occurs in four combustion pre-chambers that have an annular shape with a nozzle on the side facing the cylinder. Fuel is directly injected into the pre-chambers by using high-pressure fuel injectors. A progressive burning process is expected to keep the flame inside the pre-chambers while the fast ejection of combustion products should produce effective mixing with the cold air in the cylinder. This fast dilution should guarantee a temperature drop of the combustion products thus reducing the formation of NOx via a thermal path.

The improved design of the combustion chamber showed a positive effect in keeping the flame confined inside the pre-chambers. Changing the ignition timing by calibrating the spark advance also contributed to the confinement of the flame. With respect to the preliminary design, higher turbulent burning velocity and shorter combustion duration were found. Due to the quick and effective dilution of the burned gases with the colder air, the average temperature was found reasonably low for yielding low NOx production.
48 Development of Exhaust Valve Seat Insert Material for High Performance Engines
Authors: TAKAHASHI Teruo , KAKIUCHI Arata , SATOH Kenichi , SATOH Katsuaki , TOMINAGA Katsuhiko
Published: June 2024

Engines are assigned big subjects such as low emission and low fuel consumption as well as higher output (higher efficiency) in the latest trend of environmental protection. In order to meet these requirements, Air/Fuel ratio of recent high performance engines is being arranged leaner than that of conventional engines. As a result exhaust valve seat inserts used in these engines have problems of their wear resistance because of high exhaust gas temperature. By analyzing wear mechanism under the lean burn conditions, authors developed material for exhaust valve seat inserts which show superior wear resistance under high operating temperature. For the purpose to enhance heat resistance, authors added alloy steel powder for matrix powder and used hard particles which have good diffusion with matrix. The developed material does not include Ni and Co powders for cost saving and has superior machinability.
65 New Indicated Mean Effective Pressure Measuring Method and Its Applications
Authors: NAGASHIMA Keiichi , TSUCHIYA Kazuo
Published: June 2024

IMEP can be generally calculated by numerical integration on the PV diagram. However, this method requires a great number of sampled data per cycle, in order to ensure high accuracy in calculation. The present method is a to use only the primary and secondary components of engine speed from the pressure diagram based on the Fourier series. Owing to this method, calculation errors have become smaller than conventional method even though the number of samples is reduced, and calculation time is also reduced by the conventional method. Using present method, a Fourier series type combustion analyzing system has been developed. Real-time IMEP measurement is allowed in this system owing to the characteristic features described above, and the validity of calculated results is confirmed by comparing the results with the IMEP values obtained by batch processing through the numerical integration.
74 ENGINE SCAVENGING OPTIMIZATION
Authors: DRECQ D. , BENTEYN P.E. , du GARDIN A. , BILLMANN C.
Published: June 2024

Automotive pollutant emissions have been drastically restricted during the last ten years. These emission standards are now concerning small two-stroke engine. In order to reach future emission standard, it is essential to improve the scavenging flow, and especially the trapping efficiency of the engines. It is also interesting to have a tool for predicting the scavenging performances of an engine before the firing engine situation, which takes place late in the time scale of a development. A special test bench has been developed by D2T Group to visualize and quantify the scavenging process. It was also modelled with CFD tools, and a good correlation was observed between calculations and experimentations. This shows a good potential to reduce time and money spent in an engine development.
75 Development of an Electronically Controlled Carburetion System to Reduce the Exhaust Emissions of Small IC Engines for Handheld Power Tools
Authors: STUECKE Peter , WEGENER Holger
Published: June 2024

In order to meet the new stringent emission limits for small handheld power tools technologies like methods to improve the scavenging process and after treatment devices are deployed. Additionally, professional machines such as chain saws add particular requirements to avoid mechanical failures. By precise control of the carburetion it is possible to yield the necessary reduction of the emission level yet to maintain the performance of the engine.

Thus, the development of an Electronically Controlled Carburetion System to reduce the exhaust emissions of small IC engines for handheld power tools was initiated at the WHZ, Germany. Key requirements of such a system are: low cost, high reliability, low electrical power consumption, high accuracy in metering the fuel demand of the engine. First results are promising. A correlation between exhaust gas temperature and the fuel demand of the engine was confirmed for both, wide open throttle and part load operation. A strategy to calibrate the temperature-fuel consumption relation for individual engines or varying ambient conditions was developed. The delivery ratio between fuel demand vs. fuel supply is better than 1.5% over the range of operation.

Based on this principle it is possible to design a simple economical electronically controlled carburetion system with low electrical power consumption which is essential for the application in handheld tools.
An Experimental Study of Stratified Scavenging Activated Radical Combustion Engine
Authors: ISHIBASHI Yoichi , ASAI Masahiro , NISHIDA Kenji
Published: June 2024

From the environmental conscious point of view, subjects of conventional two-stroke engines will be irregular combustion and new mixture shortcut. Concerning for the irregular combustion, our previous papers has however proven that timing controlled auto-ignition, namely Activated Radical (AR) Combustion, was an effective solution. Meanwhile for the new mixture shortcut, no solution is mentioned in those papers.

This time, a low pressure pneumatic direct fuel injection engine has been experimented. This engine is however intended to perform homogeneous combustion, the A R Combustion solves irregular combustion effectively in the light load range. Fuel is pneumatically injected into the cylinder by using accumulated in-cylinder gas pressure, after the scavenging process performed by the air only. A mechanically driven rotary type injector is installed in the cylinder wall. Wide spray generated by this injector facilitates homogeneous combustion even in high speed high load range, which promises a higher maximum power out put. Simplicity in the mechanism and control requires a minimum additional friction and electricity to solve the irregular combustion and new mixture shortcut.

The bench test results show a remarkable reduction in fuel consumption and exhaust emissions as successfully maintaining high power out put of original two-stroke engines.
Outlook of Future Alternative Fuels and New Combustion Technology for IC engines
Authors: Yamamoto Hiroshi
Published: June 2024

Increasing consumption of petroleum fuels will eventually force us to utilize synthetic fuels made from renewable sources. This paper, after reviewing the trends of the ways how to make synthetic fuels and new combustion technologies, discusses ideas to raise the thermal efficiency of internal combustion engines (later abbreviated as ICE) to the range of 50%, so that ICE can be competitive with fuel cells whose technologies have been progressing much faster than expected. These ideas include:

1)
Active radical combustion

2)
Utilization of endothermic reaction of fuels in compression stroke

3)
Reduction of thermal dissociation of gases in expansion stroke by lowering combustion gas temperature

4)
Emulsified fuels (mixture of carbonaceous fuels with water)

5)
Fuel reforming catalysts.

The emerge of stable emulsified fuels and catalyst which can reform less combustible species of hydrocarbon to a better combustible one, gave a hint to keep ICE competitive with fuel cells.
Development of Portable Power Generator Using Polymer Electrolyte Membrane Fuel Cell
Authors: Hashimoto Noboru , Adachi Junji , Kudo Hitoshi , Shinagawa Mikio , Mizobuchi Manabu , Yamaga Noriyuki , Igarashi Akira
Published: June 2024

Butane was investigated as a fuel for a portable generator using the polymer electrolyte fuel cell (PEFC). A steam reforming technology was applied and Ru was investigated as a catalyst for a reforming process and a selective oxidation process.

It was found that Ru realized a high space velocity (SV) which enables to reduce a volume of the reformer. Reformer manufactured was connected with PEFC and operated using butane, indicating that a drop of the cell voltage was small enough. Concentration of CO in the reformate gas was less than 10ppm.
Emissions From Snowmobile Engines Using Bio-based Fuels and Lubricants
Authors: White Jeff J. , Carroll James N. , Haines Howard E.
Published: June 2024

Snowmobile engine emissions are of concern in environmentally sensitive areas, such as Yellowstone National Park (YNP). A program was undertaken to determine potential emission benefits of use of bio-based fuels and lubricants in snowmobile engines. Candidate fuels and lubricants were evaluated using a fan-cooled 488-cc Polaris engine, and a liquid-cooled 440-cc Arctco engine. Fuels tested include a reference gasoline, gasohol (10% ethanol), and an aliphatic gasoline. Lubricants evaluated include a bio-based lubricant, a fully synthetic lubricant, a high polyisobutylene (PIB) lubricant, as well as a conventional, mineral-based lubricant. Emissions and fuel consumption were measured using a five-mode test cycle that was developed from analysis of snowmobile field operating data. Emissions measured include total hydrocarbons (THC), carbon monoxide (CO), nitrogen oxides (NOx), carbon dioxide (CO2), particulate matter (PM), polycyclic aromatic hydrocarbons (PAH, both particulate bound and vapor-phase), and individual hydrocarbon species (C1-C12). Emissions and fuel consumption using bio-based fuels and lubricants were compared to results using a conventional fuel and lubricant. Promising candidates were identified and recommended for further study in a field demonstration in Yellowstone National Park.
Effect of Lean-Burn on Emission Reduction in a Small Utility 4-Stroke Spark Ignition Engine
Authors: Fukami Yoji , Yamashita Hisashi , Tamba Shininchi
Published: June 2024

From a view point of reducing exhaust emission level on a small utility 4-stroke spark-ignition engine, this paper describes the exhaust emission materials analysis and the affect against California Air Resources Board (CARB) specified testing mode on a new prototype while applying very lean mixture burning. The combustion chamber shape and the intake air passage of a production model (Displacement 286 cc, 4-stroke, air cooled, over head valve (OHV), single cylinder) was modified and optimized on the prototype to achieve a stable run up to a lean air-fuel ratio of 20 : 1. When the air-fuel ratio was changed, the highest density of NOx was a little higher than 3,000ppm at an air-fuel ratio of 16 : 1 and the lowest was about 300 ppm at an air-fuel ratio of 19 : 1. The emission level of THC was a little higher than 2,000ppm at an air-fuel ratio of 12 : 1 and less than 1,000 ppm at an air-fuel ratio of 15 : 1 and higher. This indicates that lean mixture burning is very effective in reducing exhaust emission levels. To evaluate the effect on exhaust emission reduction, the engine was tested in an air-fuel ratio range of 12 : 1 to 20 : 1 under CARB regulations. As compared to the 1995 non-hand-held category CARB regulation of CO 350 g/hp-hr and THC+NOx 10 g/hp-hr, this model brought only 30% of the CO and 75% of the THC+NOx regulation values. Moreover, when exhaust gas recirculation (EGR) was applied, the model showed 6% and 60% of the CO and THC+NOx values specified in the regulations, respectively.
A Study of Natural Gas in an Air-Cooled Spark Ignition Engine
Authors: Asar Gaber M. M. , Varde Keshav S. , Sabry Taher I. , Sileem Ahmed A.
Published: June 2024

An experimental study was conducted to determine potential of natural gas in lowering exhaust emissions from small spark ignition engines. A single cylinder, four-stroke, air-cooled spark ignition engine was used in the study. The investigation showed that increasing engine compression ratio from 8:1 to 10:1 reduced penalty in power normally associated with natural gas engine. The engine was able to run very stable at equivalence ratio as lean as 0.65 while the same engine could not be run at equivalence ratio below 0.85 on gasoline. Best thermal efficiency and reduced emissions of hydrocarbons and oxides of nitrogen were realized around equivalence ratio 0.75. Reducing equivalence ratio further lowered emissions of oxides of nitrogen significantly while increase in hydrocarbons was small. Most of the hydrocarbons in exhaust were of the methane type which have low ozone forming reactivity.
Integrated Control Device of Exhaust Throttle, Air Induction and Ignition for Emission Reduction
Authors: OHIRA Tetsuya , MISHINA Fusayuki , KOBAYASHI Manabu
Published: June 2024

The purpose of this study is to evaluate the effect of an exhaust throttle installed in an exhaust pipe in a two-stroke motorcycle engine. In the experimental study, the exhaust-throttle system prevented fresh-gas from short-circuiting and consequently, improved unburnt hydrocarbon emissions and fuel economy, along with enhancing combustion stability. In actual running, in order to minimize HC emission level and stabilize cycle-to-cycle fluctuation of combustion including intermittent misfiring, an air-induction system and a long-duration spark ignition were used in addition to the exhaust throttle system. The control software for the integrated system was also a key point in improving HC and CO emission levels in the ECE-40 operation cycle. For detecting misfiring in the ECE-40 cycle, time-resolved HC variation was measured by a fast-response gas analyzer.
Two-Stroke Engine Design With Selective Exhaust Gas Recirculation - a Concept
Authors: Mavinahally Nagesh S. , Kamo Roy , Ganesan V.
Published: June 2024

High unburned hydrocarbon emissions and poor fuel consumption arise in a carburetted two-stroke engine because of its scavenging process. Time resolved hydrocarbon concentration at the exhaust port has shown a definite trend in concentration of unburned hydrocarbon with respect to crank angle. This paper discusses an exhaust gas recirculation system designed to trap fraction of the exhaust gas that is rich in short circuited fresh charge. In this design, the differential pressure between the crankcase and the exit at the exhaust port is communicated with each other at the appropriate time through passages in the piston and the cylinder block. The design is thus capable of selectively trapping and recirculating fraction of the exhaust gas rich in short circuited fresh charge back into the cylinder for combustion. Experimental results of other researchers related to time resolved exhaust gas constituents, and performance of two-stroke engine with the selective exhaust gas recirculation are also discussed.
Development of New 3.3 Liters Diesel Engine Series for Agricultural and Industrial Use
Authors: Takii Osamu , Miyazaki Manabu , Hasegawa Hideo
Published: June 2024

In this paper, the features of V3300 heavy-duty diesel engine series and the technologies to achieve the concepts are introduced.

V3300 series is the vertical water-cooled 4 cycle IDI diesel engine for agricultural and industrial use. Its output is the highest in our company's IDI diesel engines. V3300 series was developed based on the concepts of our conventional series (low vibration, low noise, clean exhaust emissions and good fuel efficiency).

V3300 series adopts 3 valves system for the first time in agricultural and industrial diesel engines. This 3 valves system is composed of 2 intake valves and 1 exhaust valve per cylinder. V3300 series also adopts the new combustion system which succeeded to the KUBOTA's original combustion system. The volumetric efficiency, the fuel efficiency and the exhaust emission performance are improved by these systems. The comfort level is achieved by reduction of the vibration and the noise by adoption of the built-in balancer.
Influence of the Front Fork on the Movement of a Motorcycle
Authors: Kamioka Takamasa , Yoshimura Naoyuki , Sato So
Published: June 2024

Front Fork (“FF”) of a motorcycle has some characteristics; spring force, damping force, stiffness and so on. They have great influence on the movement of a motorcycle. Under the present conditions, the settings of FF characteristics are tuned up through trial and error by rider's evaluation of driving, and so we need much time and cost.

In this research, we model the detail of the inner structure of a FF, and calculate damping force. Then, we verify that calculated results correspond well with experimental ones. And we make a simulation model of a motorcycle considered the detail FF model by using mechanical analytical language, and it is verified that the simulation correspond with the experimental results. So, it is verified by simulation how the movements of a motorcycle be varied according to the different of FF characteristics.

In conclusion, though limited in some running conditions, we have cleared the relation between the FF characteristics and the movement of a motorcycle. Now, the research enabled us to predict some characteristics of FF by simulation instead of them decided by trial and error.
Dezinformacja na temat COVID-19 w mediach społecznościowych a kryzys epistemiczny. Przegląd problemów
Authors: Barański Jarosław , Smereka Jacek
Published: June 2024

The text considers several critical issues related to the role of false information in the COVID-19 pandemic. It mainly focuses on social media, which often resemble echo chambers responsible for disseminating disinformation. In these echo chambers, users close themselves off from arguments and justifications different from their own, often with a strong tendency towards polarization of views and attitudes. A particular case of echo chambers is the conspiracy mentality propagated in social media, promoting conspirational beliefs about COVID-19, which, besides offering an alternative understanding of reality, deepens distrust towards epistemic authorities and methods of producing scientific knowledge. This indicates an epistemic crisis as a consequence of the pandemic, which must be addressed in order to rebuild and protect epistemic trust. The authors conclude that the consequence of this crisis is a regression of cognitive abilities, which may, in a feedback loop, exacerbate the epistemic crisis.
Wykorzystanie elementów dziedzictwa kulturowego i tożsamości lokalnej a jakość przestrzeni publicznej na obszarach wiejskich w Polsce
Authors: Jamróz-Woźniak Joanna
Published: June 2024

Celem pracy jest wskazanie powiązań między wykorzystaniem elementów dziedzictwa kulturowego i tożsamości lokalnej a jakością projektów przestrzeni publicznych realizowanych na terenach wiejskich. Badanie, przeprowadzone przez autorkę na próbie 231 inwestycji, które zostały dofinansowane ze środków Unii Europejskiej na operację pod nazwą „Kształtowanie przestrzeni publicznej”, w ramach działania „Podstawowe usługi i odnowa wsi na obszarach wiejskich” objętego Programem Rozwoju Obszarów Wiejskich na lata 2014–2020, wykazało, że polska wieś jest miejscem rozwoju ogólnodostępnych funkcji sportowych i rekreacyjnych, jednak przeważnie w przestrzeniach o niskim stopniu innowacyjności, schematycznych oraz niewykorzystujących swoich lokalnych potencjałów i tradycji. Jednocześnie analiza projektów zrealizowanych w ramach Programu potwierdziła, że podkreślenie tożsamości lokalnej i historii danego miejsca jest związane z innowacyjnym podejściem do projektowania ruralistycznego, a w efekcie może oddziaływać na holistyczną ocenę i walory danej inwestycji. Wykorzystanie elementu genius loci stanowi czynnik, który w istotnym stopniu wpływa na wartość przestrzeni publicznej, pozwala na zachowanie odrębności oraz wspiera rozwój poszczególnych miejscowości w Polsce. Wyniki badania sugerują, że odwołanie do elementów dziedzictwa kulturowego i tożsamości lokalnej może przyczynić się do odwrócenia negatywnych zjawisk obserwowanych w fizjonomii obszarów wiejskich w ostatnich latach, takich jak typizacja form architektonicznych narzucająca powszechną unifikację, a także odcięcie od lokalnych zwyczajów i tożsamości miejsca.
Visitors’ perception of crowding. A case study from the Tatra Mountains
Authors: Hibner Joanna , Zięba Antoni , Filar Bogusława , Taczanowska Karolina
Published: June 2024

Protected areas (PAs) serve as significant tourist destinations, drawing a substantial number of visitors annually. Over the past century, managers and scientists overseeing PAs have sought to identify indicators that specify the maximum number of tourists that could visit a particular area without making a large impact on the environment. As a result, the carrying capacity theory was created, which now evolved into the concept called Limits of Acceptable Changes (LAC). This concept is based on the expected conditions that should be met in a protected area in both ecological and social aspects. This study aims to assess the tolerable level of congestion in a cable car destination situated in the Tatra Mountains and, in addition, to obtain information on the factors that affected the differences in visitors’ perception of crowding. Data used in the analysis were collected as part of two research projects: focused on the Kasprowy Wierch area (Poland) and the Skalnaté Pleso area (Slovakia). To gain information on the perception of crowding by visitors, on-site surveys were conducted during the summer season of 2014 and 2015 at both sites. The research results show that the acceptance of crowding decreases with the increasing number of visitors in research areas and it is affected by the type of research area. The analysis also reveals that the acceptance of crowding is also dependent on socio-demographic and social factors such as the level of educational attainment of the respondents, the type of trip or the size of the group.
Zeolites and their composites as novel remediation agent for antibiotics: A review
Authors: Verma Yaksha , Sharma Gaurav , Kumar Amit , Wang Tongtong , Dhiman Pooja , Mola Genene Tessema
Published: June 2024

Antibiotic residues in aquatic environments pose significant challenges when exceeding permissible limits. Zeolites, particularly aluminosilicate zeolites, have emerged as effective adsorption materials and solid substrates for semiconductor photocatalysts, facilitating the removal of antibiotics from wastewater. This review highlights the versatility of zeolites and their composites in antibiotic remediation, showcasing recent advancements in adsorption and photocatalytic degradation. Noteworthy examples include Fe (III)-modified synthetic zeolite 13X, exhibiting a maximum tetracycline adsorption capacity of approximately 200 mg/g, and MoS2@Zeolite achieving a remarkable efficiency of 396.70 mg/g for tetracycline removal. Additionally, zeolite-based photocatalysts like Fe-TiO2/BEA zeolite and exceptional CdS/CaFe2O4-clinoptilolite demonstrate high removal percentages, reaching 100% for tetracycline and 86% for cefazolin, respectively. The discussion encompasses an introduction to zeolites, including synthetic and natural zeolites, as well as techniques for modifying natural zeolites. It further delves into the production of synthetic zeolites as well as the fabrication of zeolite-based composite materials. These findings underscore the potential of zeolites and their composites as novel remediation agents for tackling antibiotic contamination in aquatic ecosystems, paving the way for sustainable wastewater treatment strategies. It highlights key elements, distinct qualities, and areas needing further research, paving the way for future studies.
Sonochemical synthesis and characterization of Fe(II) and Cu(II) nano-sized complexes of sulfamethoxazole
Authors: Asogwa B. C. , Otuokere I. E.
Published: June 2024

Nanoparticle drug delivery systems are precisely designed technologies that utilize nanoparticles to deliver therapeutic drugs to specific targets and regulate their release. In recent times, nanoparticles have garnered significant interest owing to their potential for efficient drug delivery. This work is aimed at synthesizing Fe(II) and Cu(II) nano-sized complexes of sulfamethoxazole (SMX) using the sonication method. The physical and spectroscopic studies showed a colour change from white to grey, and a decrease in melting points suggested the formation of the metal complexes. The nanometal complexes were insoluble in water. XRD analysis showed that the crystallite sizes of Fe(II) and Cu(II) nanometal complexes were determined to be 76.08 nm and 37.13 nm, respectively, using the Debye-Scherrer equation. The FTIR results of the SMX, Fe(II), and Cu(II) nanometal complexes showed a shift of the amine band from 3243 to 3191 cm^-1 and the sulfone band from 1154 to 1092 cm^-1 in both complexes. The proton NMR showed a shift of the amine proton from 6.100 ppm to 6.035 ppm in the spectra of the Cu(II) complex. The amine chemical shift was absent in the spectra of the Fe(II) complex, showing deprotonation. The carbon-13 NMR spectra showed a similar chemical shift. The spectra studies indicated that SMX coordinated with the metal ions through the amino and sulfone groups. A tetrahedral structure was proposed for the complexes. SMX coordinated as a bidentate ligand to Fe(II) and Cu(II) ions.
A Framework to Improve the Implementations of Linear Layers
Authors: Yuan Yufei , Wu Wenling , Shi Tairong , Zhang Lei , Zhang Yu
Published: June 2024

This paper presents a novel approach to optimizing the linear layer of block ciphers using the matrix decomposition framework. It is observed that the reduction properties proposed by Xiang et al. (in FSE 2020) need to be improved. To address these limitations, we propose a new reduction framework with a complete reduction algorithm and swapping algorithm. Our approach formulates matrix decomposition as a new framework with an adaptive objective function and converts the problem to a Graph Isomorphism problem (GI problem). Using the new reduction algorithm, we were able to achieve lower XOR counts and depths of quantum implementations under the s-XOR metric. Our results outperform previous works for many linear layers of block ciphers and hash functions; some of them are better than the current g-XOR implementation. For the AES MixColumn operation, we get two implementations with 91 XOR counts and depth 13 of in-place quantum implementation, respectively.
Farklı Disiplinlerde Lisansüstü Eğitim Almış Kadınların Kraliçe Arı Sendromu Algısı
Authors: Mert Mahan Kübra , Orujzade Parvın
Published: June 2024

Kraliçe arı sendromu, kadınların kariyerlerinde karşı karşıya kaldığı önemli bir sorundur. Kraliçe arılar erkek egemen organizasyonlarda, diğer kadınlardan ne kadar farklı olduklarını vurgulayarak başarıya ulaşmış kıdemli kadınlardır. Kraliçe arı sendromuna göre, bir kraliçe arının bir kovanın tek yöneticisi olmak istemesi gibi, kadınlar da çalıştıkları organizasyonlarda yönetici pozisyonlarına tek başına yükselmek istemektedir. Ancak bu sendrom sadece kadın yöneticilerde görülmemektedir. Bu bağlamda çalışmanın amacı, kadın akademisyenlerin kariyer gelişimlerini nasıl sınırladığını tespit etmek amacıyla lisansüstü eğitim almış kadınlarda kraliçe arı sendromunu incelemektir. Çalışmada, nitel araştırma yöntemi kullanılmıştır. Araştırmanın örneklemini Türkiye’de bulunan üniversitelerde lisansüstü eğitim almış ve danışmanı kadın olan dokuz kadın oluşturmaktadır. Bu katılımcılara veri toplamak amacıyla lisansüstü eğitim almış kadınların yaşadıkları sorunlara ilişkin “cinsiyet, medeni durum, çalışma planı, danışmanıyla ilişkileri veya aralarındaki engeller” gibi faktörlerin incelendiği on beş adet açık uçlu yarı-yapılandırılmış soru iletilmiştir. Verilen cevaplar, içerik analizi ile yorumlanmıştır. Elde edilen veriler deşifre edilip, kodlanıp yorumlandığında örneklemde yer alan kadınların lisansüstü eğitim süreçlerinde danışmanları tarafından kraliçe arı davranışlarına maruz kalmadıkları görülmüştür.
Program Prakerja sebagai Peningkatan Kualitas Kerja dalam Perspektif Komunikasi Pembangunan dan Tujuan Pembangunan Berkelanjutan
Authors: Febrian Muhammad Rifqi , Hamim Rokhi Nur
Published: June 2024

Program Prakerja merupakan inisiatif pemerintah Indonesia yang bertujuan untuk meningkatkan kualitas tenaga kerja melalui pelatihan dan pendidikan. Dalam perspektif komunikasi pembangunan, program ini tidak hanya berfungsi sebagai alat peningkatan keterampilan individu, tetapi juga sebagai medium penyebaran informasi dan edukasi yang efektif kepada masyarakat luas. Program ini memainkan peran penting dalam meningkatkan produktivitas dan meningkatkan kompetensi pekerja, sehingga mereka lebih siap menghadapi tantangan di pasar kerja yang dinamis. Penelitian ini menggunakan metode penelitian kualitatif dengan tipe deskriptif analisis. Hasil penelitian menunjukkan Program Prakerja berkontribusi signifikan terhadap pencapaian Tujuan Pembangunan Berkelanjutan (TPB) atau Sustainable Development Goals (SDGs), khususnya pada poin pendidikan berkualitas, pekerjaan layak, dan pertumbuhan ekonomi. Melalui analisis komunikasi pembangunan, artikel ini mengeksplorasi bagaimana Program Prakerja mengintegrasikan prinsip-prinsip tersebut untuk menciptakan dampak positif yang berkelanjutan dalam masyarakat. Implementasi yang efektif dan strategis dari program ini diharapkan dapat memberdayakan peserta secara ekonomis dan sosial, serta mendorong pembangunan yang inklusif dan berkelanjutan di Indonesia.
Studi Literatur: Analisis Pengaruh Ragam Karakteristik Pekerja Ekonomi Gig terhadap Perekonomian Nasional
Authors: Izza Sevilla Ruhul , Saharani Kharisma Dewantika , Ardiani Della , Franssisca Maria Lasma
Published: June 2024

Transformasi ekonomi digital yang berkembang pesat menjadi sumber kekuatan baru bagi pertumbuhan ekonomi yang inklusif dan berkelanjutan sehingga melahirkan fenomena ekonomi gig yang merujuk pada model pekerjaan sementara, mandiri, dan fleksibel dengan memanfaatkan platform digital atau aplikasi. Tujuan dari penelitian ini adalah menganalisis pengaruh dari ragam karakteristik pekerja ekonomi gig terhadap perekonomian nasional berdasarkan basis lokasi (superapp) dan basis jarak jauh (online). Metode penelitian ini menggunakan analisis studi literatur berupa data sekunder dengan proses pengumpulan data melalui buku, jurnal ilmiah, data digital, dan dokumen terkait ekonomi gig dan perekonomian nasional. Hasil penelitian menunjukkan transformasi ekonomi digital telah melahirkan ragam karakteristik pekerja ekonomi gig berbasis lokasi (superapp) dan berbasis jarak jauh (online). Pengaruh pekerja ekonomi gig terhadap perekonomian nasional ditunjukkan melalui penyerapan tenaga kerja, tersedianya lapangan kerja baru, dan kontribusi terhadap Produk Domestik Bruto (PDB) di Indonesia.
Pengaruh Covid-19 pada Kesehatan Mental Peserta Didik Remaja dengan Kecenderungan Depresi: Sebuah Sistematik Review
Authors: Angelia Putri , Ihsannudin Raihan
Published: June 2024

Kesejahteraan mental peserta didik adalah hal yang penting untuk dipahami. Penelitian ini bertujuan untuk mengevaluasi dampak pandemi Covid-19 terhadap kondisi kesehatan mental, khususnya depresi, di kalangan peserta didik. Metode yang digunakan adalah tinjauan literatur sistematis, di mana semua artikel yang ditemukan disaring berdasarkan kriteria inklusi, eksklusi, dan evaluasi kualitas. Data yang digunakan berasal dari basis data publikasi seperti PubMed, PNRI, ScienceDirect, dan Google Scholar, menggunakan beberapa kata kunci yaitu kesehatan mental, pandemi Covid-19, depresi, dan remaja. Berdasarkan tinjauan, dapat disimpulkan bahwasanya pandemi Covid-19 berdampak signifikan pada tingkat depresi peserta didik. Depresi juga dapat disebabkan oleh perubahan pola hidup seperti social distancing, pembelajaran daring, penutupan sekolah, dan lockdown di kalangan peserta didik. Penelitian ini memiliki implikasi yang penting dengan menyediakan landasan awal bagi peneliti yang tertarik pada masalah kesehatan mental landasan untuk penelitian lanjutan.
Enhancing Learning Performance of students in Tourism major at Ba Ria - Vung Tau University
Authors:   Ba Ria - Vung Tau University, Duc Dat Nguyen
Published: June 2024

Ba Ria – Vung Tau University, a tourism education institution in Vietnam, has implemented a multifaceted approach to optimize the learning performance of its tourism management students. This article examines the university’s strategies, which include curriculum design and relevance, integration of technology and digital literacy, experiential learning and industry partnerships, mentorship and career guidance, fostering student engagement and well-being, and a continuous improvement and evaluation process. The university’s comprehensive initiatives aim to prepare the next generation of tourism professionals by enhancing their knowledge, practical skills, and overall competitiveness in the dynamic and rapidly evolving tourism industry.