scholarly journals Experimental Investigation of the Viscosity Parameters Ranges—Case Study of Engine Oils in the Selected Viscosity Grade

Energies ◽  
2020 ◽  
Vol 13 (12) ◽  
pp. 3152 ◽  
Author(s):  
Artur Wolak ◽  
Grzegorz Zając ◽  
Kamil Fijorek ◽  
Piotr Janocha ◽  
Arkadiusz Matwijczuk
Keyword(s):  
Energy Efficient ◽  
Kinematic Viscosity ◽  
Primary Objective ◽  
Laboratory Measurements ◽  
Mahalanobis Distances ◽  
Engine Oils ◽  
Secondary Objective ◽  
Viscosity Grade ◽  
The Difference

The primary objective of the research was to compare the viscosity parameters of the same viscosity grade engine oils, as declared by the manufacturers, to the actual laboratory measurements. The secondary objective was to briefly investigate (1) what kind of information oil manufacturers provide in the product data sheets of the studied oils, and (2) the potential savings resulting from the use of the energy efficient oils. The study material consisted of 42 selected synthetic engine oils that belong to the 5W-30 viscosity grade. Stabinger SVM 3001 viscometer was used to determine kinematic viscosity at −20 °C, 40 °C, 100 °C and 130 °C. The HTHS (high temperature high shear), CCS (cold cranking simulator), FTIR (Fourier-transform infrared spectroscopy) and GC (Gas Chromatography) measurements were also performed for the samples that had the lowest and the highest kinematic viscosity. Large differences (5–25%) between oil producers’ declarations and the results of laboratory tests were found. Although all of the engine oils tested met the 5W-30 grade standards, the high variability of viscosity measurements needs to be reported. The difference between the oil with the highest and the oil with the lowest kinematic viscosity at −20 °C was 11,804 mm2/s. The outlying temperature-related viscosity profiles were recovered using Mahalanobis distances which identified 16 out of 42 analyzed oil samples as atypical.

scholarly journals The Effectiveness Of High Levels Of Knowledge Regarding Hiv/Aids In Reducing Discriminatory Attitudes And Behaviour Towards Hiv-Infected People

2006 ◽  
Vol 4 (1) ◽  
Author(s):  
M. Pirie ◽  
W. J. Coetsee
Keyword(s):  
Sample Size ◽  
Primary Objective ◽  
Large Sample Size ◽  
Infected People ◽  
Eta Squared ◽  
Secondary Objective ◽  
Level Of Knowledge ◽  
The Difference ◽  
F Statistics ◽  
Hiv Aids

The primary objective of this study was to assess whether there is a relationship between increasing levels of knowledge about HIV/AIDS and perceptions of discriminatory attitudes and behaviour towards people with HIV/AIDS. Employees (3662) from a large accounting firm were exposed to a survey and a response rate of 41% or 1532 was received. The secondary objective of the study was to determine whether there were any statistically significant differences in the mean difference of knowledge scores of groups created in terms of the different biographical variables. ANOVA’S (to determine the significance of differences between the means), t-tests (two groups only) and F-statistics were used for the analysis. Given the large sample size an F-test is not conclusive and the effect of the difference in sample size needs to be taken into account. For this reason it was also necessary to look at the Partial Eta Squared. Results indicate that respondents are generally knowledgeable about the prevention and transmission of HIV/AIDS and that respondents’ level of knowledge correlates negatively with discriminatory practices.

scholarly journals Diagnosis associated with COVID-19 (U07.1), Pneumonia- Unspecified (J18.9) and other types of admissions: A restricted medical scheme case study- South Africa

2021 ◽  
Vol 8 (1) ◽  
pp. 001-016
Author(s):  
Michael Mncedisi Willie ◽  
◽  
Asnath Motsepe ◽  
Keyword(s):  
Private Hospital ◽  
Hospital Admissions ◽  
Primary Objective ◽  
Inclusion Criteria ◽  
Pcr Assay ◽  
Private Hospitals ◽  
Review Period ◽  
Icd 10 ◽  
Secondary Objective

The primary objective of this study was to assess the characteristics of patients admitted for COVID-19, ‘J18.9 Pneumonia, unspecified organism’ and other types of diagnoses. The aim was to assess as to what extent do COVID-19 related admissions changed to pneumonia, and as to what extent do ‘J18.9 Pneumonia, unspecified organism’ related admissions that changed to COVID-19 diagnosis at discharge stage. The secondary objective of the study was to assess’ predictors of readmissions in private hospitals. The review period was private hospital claims received by the scheme between January and August 2020. The inclusion criteria for COVID-19 admissions were patients that had a laboratory-confirmed (RT – PCR assay) COVID-19. Predictors of readmissions were modelled using logistic regression. The study found that restricted scheme patients admitted for a COVID-19 diagnosis changed to a ‘J18.9 Pneumonia, unspecified organism’ diagnosis. The converse was found to be true in that some patients that were admitted as J18.9 Pneumonia, unspecified organism’ diagnosis changed to a COVID-19 diagnosis. This study showed underlying factors associated with hospital admissions and predictors of readmissions in private hospitals. Keywords: COVID-19, Diagnosis, Hospitalisation, ICD-10, Pneumonia, Risk factors

Design, Model, and Virtually Fly: Investigation of the B-1A Cruise Performance With F101 Engines Compared With Its Re-Engined Performance Using F119 Engines

2011 ◽  
Author(s):  
August J. Rolling
Keyword(s):  
Primary Objective ◽  
Integrated System ◽  
Actual Case ◽  
Modular Software ◽  
Engine Design ◽  
Polar Model ◽  
Secondary Objective ◽  
Insight Into ◽  
Geospatial Mapping

This paper examines application of AEDSYS and MATLAB design tools to virtually fly an engine in a platform through a mission. The primary objective of this effort was to develop the procedures for this process as an instructional tool. The secondary objective was application of the process to an actual case study, the re-engine of the B-1A. The resulting modular software uses performance data from engine models for the F101, F119, and a cadet designed engine built in AEDSYS; a B-1A drag polar model; as well as atmospheric and geospatial mapping tools available in MATLAB. The resulting simulation provides a relatable means of presenting this complicated information. This tool gives the cadets the opportunity to virtually fly their engine. This visualization gives them full insight into how the integrated system performs. Aside from providing a great means of discussing many aspects for consideration in engine design, it also provides an incentive to develop a higher performance engine through competition.

scholarly journals Non-Financial Support Provided to Parents in Stepfamilies: Empirical Examination of Europeans 50+

2021 ◽  
Vol 18 (10) ◽  
pp. 5151
Author(s):  
Małgorzata Kalbarczyk
Keyword(s):  
Financial Support ◽  
Primary Objective ◽  
Empirical Examination ◽  
Older Parents ◽  
Intact Families ◽  
Relationship Closeness ◽  
Biological Children ◽  
Secondary Objective ◽  
The Difference ◽  
Natural Child

The aging of the population, coupled with increasing divorce and remarriage rates, are changing the structure of potential non-financial support for older parents. The purpose of this study was to examine support provided to parents aged 50+ in stepfamilies and to determine if the difference existed between help provided by natural children and stepchildren. The primary objective was to investigate whether blood ties were a significant determinant of the support if the quality of the relationship between the parent and a natural child or a stepchild was taken into account. The secondary objective was to answer the question to what extent the reciprocal exchange motive of support was observed in stepfamilies. The probability of non-financial support from children and stepchildren was estimated based on the sixth wave of the SHARE (Survey on Health, Ageing, and Retirement in Europe) database for European countries. Children in stepfamilies provided less non-financial help to parents than those in intact families. Stepchildren were less likely to be in stepparents’ social networks, and stepparents provided less help with childcare for grandchildren than they did to their biological children. Relationship closeness and looking after grandchildren increased the probability of non-financial support to older parents, regardless of whether the donor was a natural child or a stepchild.

Is commercial reed harvesting compatible with breeding purple herons Ardea purpurea in the Camargue, southern France?

2000 ◽  
Vol 27 (4) ◽  
pp. 334-340 ◽  
Author(s):  
Christophe Barbraud ◽  
Raphael Mathevet
Keyword(s):  
European Union ◽  
Economic Development ◽  
Environmental Policy ◽  
Primary Objective ◽  
Present Form ◽  
Breeding Habitat ◽  
Southern France ◽  
The Difference ◽  
Urgent Action

Reedbeds of the Rhône river delta, southern France, constitute an important breeding habitat for purple herons (Ardea purpurea) in Europe. However, the area of reed harvested commercially has increased in recent years and, since 1997, a European Union agri-environmental policy has been implemented to reconcile economic development with conservation goals for harvested reedbeds. Here, we investigate trends in breeding numbers of purple herons and the effect of reed harvesting on reedbed occupancy by herons. A regression model indicates that reedbed use by breeding herons was negatively affected by the reed harvesting pressure. An increase of nearly 50% in the harvested area following the implementation of the policy was probably caused by subsidies (from 67 to 100 US$/ha/year) proposed to reed harvesters, although associated with harvesting constraints intended to conserve heron colonies. The difference between the payments with and without colonies does not appear to have been sufficient to convince reed harvesters to conserve colonies. A case study showed that one heron colony located in a reserve area persisted, while another split into smaller colonies following modifications of reedbeds for future reed harvesting. Results suggest that the agri-environmental policy in its present form has failed to accomplish its primary objective of improving conditions for breeding purple herons in the Camargue. Potential breeding habitat for purple herons have decreased and urgent action is needed to protect some reedbeds from intense reed cutting.

scholarly journals Agreement between Arterial and Capillary pH, pCO2, and Lactate in Patients in the Emergency Department

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Vincent Collot ◽  
Stefano Malinverni ◽  
Jabir Haltout ◽  
Eric Schweitzer ◽  
Pierre Mols ◽  
...  
Keyword(s):  
Lactic Acidosis ◽  
Sensitivity And Specificity ◽  
Blood Gas Analysis ◽  
Primary Objective ◽  
Gas Analysis ◽  
Mean Difference ◽  
Plot Analysis ◽  
High Concordance ◽  
Secondary Objective ◽  
The Difference

Background. Blood gas analysis (BGA) is a frequent painful procedure in emergency departments. The primary objective of the study was a quantitative analysis to assess the mean difference and 95% confidence interval of the difference between capillary and arterial BGA for pH, pCO2, and lactate. Secondary objective was to measure the sensitivity and specificity of capillary samples to detect altered pH, hypercarbia, and lactic acidosis. Adults admitted to the ED were screened for inclusion. We studied the agreement between the two methods for pH, pCO2, and lactate with Bland-Altman bias plot analysis and receiver operating characteristic curves. Results. One hundred ninety-seven paired analyses were included. Mean difference for pH between arterial and capillary BGA was 0.0095, and 95% limits of agreement (LOA) were −0.048 to 0.067. For pCO2, mean difference was −0.3 mmHg, and 95% LOA were −8.5 to 7.9 mmHg. Lactate mean difference was −0.93 mmol/L, and 95% LOA were −2.7 to 0.8 mmol/L. At a threshold of 7.34, capillary pH had 98% sensitivity and 97% specificity to detect acidemia; at 45.9 mmHg, capillary pCO2 had 89% sensitivity and 96% specificity to detect hypercarbia. At a threshold of 3.5 mmol/L, capillary lactate had 66% sensitivity to detect lactic acidosis. Conclusion. Capillary BGA cannot replace arterial BGA despite high concordance between the two methods for pH and pCO2 and moderate concordance for lactate. Capillary measures had good accuracy when used as a screening tool to detect altered pH and hypercarbia but insufficient sensitivity and specificity when screening for lactic acidosis.

scholarly journals Temperature dependent kinematic viscosity of different types of engine oils

2009 ◽  
Vol 57 (4) ◽  
pp. 95-102 ◽  
Author(s):  
Libor Severa ◽  
Miroslav Havlíček ◽  
Vojtěch Kumbár
Keyword(s):  
Kinematic Viscosity ◽  
Engine Oil ◽  
Combustion Engines ◽  
Temperature Dependent ◽  
Engine Oils ◽  
Concentric Cylinders ◽  
Viscosity Behavior ◽  
Viscosity Grade ◽  
And Performance ◽  
Increasing Temperature

The objective of this study is to measure how the viscosity of engine oil changes with temperature. Six different commercially distributed engine oils (primarily intended for motorcycle engines) of 10W–40 viscosity grade have been evaluated. Four of the oils were of synthetic type, two of semi–synthetic type. All oils have been assumed to be Newtonian fluids, thus flow curves have not been determined. Oils have been cooled to below zero temperatures and under controlled temperature regulation, kinematic viscosity (mm2 / s) have been measured in the range of −5 °C and +115 °C. Anton Paar digital viscometer with concentric cylinders geometry has been used. In accordance with expected behavior, kinematic viscosity of all oils was decreasing with increasing temperature. Viscosity was found to be independent on oil’s density. Temperature dependence has been modeled using se­ve­ral mathematical models – Vogel equation, Arrhenius equation, polynomial, and Gaussian equation. The best match between experimental and computed data has been achieved for Gaussian equation (R2 = 0.9993). Knowledge of viscosity behavior of an engine oil as a function of its temperature is of great importance, especially when considering running efficiency and performance of combustion engines. Proposed models can be used for description and prediction of rheological behavior of engine oils.

The Student Room Survey: Changes in the Post Graduate Study for Cardiothoracic Surgery

2020 ◽  
Vol 23 (2) ◽  
pp. 71-74
Author(s):  
Md Faizus Sazzad ◽  
Mohammed Moniruzzaman ◽  
Dewan Iftakher Raza Choudhury ◽  
Arif Ahmed Mohiuddin ◽  
Raafi Rahman ◽  
...  
Keyword(s):  
Thoracic Surgery ◽  
Retrospective Analysis ◽  
Primary Objective ◽  
Graduate Study ◽  
Postgraduate Students ◽  
Depth Interview ◽  
Secondary Objective ◽  
Cardio Vascular ◽  
The University ◽  
Day By Day

Background: The number of postgraduate students in Cardiac surgical discipline is increasing day by day with incremental proportion are measurably suffering from the unnecessary lingering of the present course curriculum. The primary objective of this study was to find out the last 5 years’ of results of Masters in Surgery course under the University of Dhaka from a student room survey. A secondary objective was to find out positive changes that could show us the way of a step toward up-gradation. Methods: It is a retrospective analysis of all examination results of Cardio-vascular & Thoracic Surgery published since January 2008 to January 2013 from the University of Dhaka with in depth interview of 11 participants. Results: 85.24% students failed to pass part-I of Masters in Surgery for Cardio-vascular & Thoracic Surgery course while, 82.18% in part-II and 71.28% failed to pass the final part. Average 2.51 attempts needed to complete each part of the designed course resulted into lingering of course duration for 42.18 months/student. In the thoracic surgery discipline the number of students alarmingly reduced up to 0% in the recent academic sessions. Conclusions: Masters in Surgery is resulting in unnecessary prolongation of the course. We should step forward to meet the next generation challenge. Journal of Surgical Sciences (2019) Vol. 23(2): 71-74

Epidemiology of pheochromocytoma and paraganglioma: population-based cohort study

2021 ◽  
Vol 184 (1) ◽  
pp. 19-28
Author(s):  
Alexander A Leung ◽  
Janice L Pasieka ◽  
Martin D Hyrcza ◽  
Danièle Pacaud ◽  
Yuan Dong ◽  
...  
Keyword(s):  
Cohort Study ◽  
Administrative Data ◽  
Laboratory Data ◽  
Population Based ◽  
Incidence Rates ◽  
Primary Objective ◽  
Administrative Databases ◽  
Secondary Objective ◽  
True Frequency ◽  
Clinical Records

Objective Despite the significant morbidity and mortality associated with pheochromocytoma and paraganglioma, little is known about their epidemiology. The primary objective was to determine the incidence of pheochromocytoma and paraganglioma in an ethnically diverse population. A secondary objective was to develop and validate algorithms for case detection using laboratory and administrative data. Design Population-based cohort study in Alberta, Canada from 2012 to 2019. Methods Patients with pheochromocytoma or paraganglioma were identified using linked administrative databases and clinical records. Annual incidence rates per 100 000 people were calculated and stratified according to age and sex. Algorithms to identify pheochromocytoma and paraganglioma, based on laboratory and administrative data, were evaluated. Results A total of 239 patients with pheochromocytoma or paraganglioma (collectively with 251 tumors) were identified from a population of 5 196 368 people over a period of 7 years. The overall incidence of pheochromocytoma or paraganglioma was 0.66 cases per 100 000 people per year. The frequency of pheochromocytoma and paraganglioma increased with age and was highest in individuals aged 60–79 years (8.85 and 14.68 cases per 100 000 people per year for males and females, respectively). An algorithm based on laboratory data (metanephrine >two-fold or normetanephrine >three-fold higher than the upper limit of normal) closely approximated the true frequency of pheochromocytoma and paraganglioma with an estimated incidence of 0.54 cases per 100 000 people per year. Conslusion The incidence of pheochromocytoma and paraganglioma in an unselected population of western Canada was unexpectedly higher than rates reported from other areas of the world.

Incidência da utilização de protetores bucais em diversos esportes de contato

2020 ◽  
Vol 12 (45) ◽  
pp. 118-122
Author(s):  
Victor Paes Dias Gonçalves ◽  
Hugo Leonardo Matias Nahmias ◽  
Marcus Menezes Alves Azevedo
Keyword(s):  
Martial Arts ◽  
Rio De Janeiro ◽  
Dental Trauma ◽  
Primary Objective ◽  
Type Ii ◽  
Contact Sports ◽  
The Face ◽  
Secondary Objective ◽  
The City

Among contact sports, the practice of martial arts offers a greater risk of causing dental trauma and fractures as contact with the face is more frequent. The primary objective of the research is to evaluate the incidence of mouthguard use, and the secondary objective is to verify which type has a greater predominance and the difficulties in its use correlating to the type of mouthguard used. A documentary study was carried out with 273 athletes of different contact sports, among them: MMA, Boxing, Muay Thai, Jiu-Jitsu, and Taekwondo of the city of Campos dos Goytacazes, Rio de Janeiro, Brazil. It was concluded that the most commonly used mouthguard is PB Boils and Bites - Type II and its level of approval is poor, interfering with the athletes’ performance, mainly in relation to the breathing factor.

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