Impact of Ageing on Tribological Properties of Environmentally Friendly Hydraulic Fluids

2002 ◽  
Author(s):  
Martin Schmidt ◽  
Hubertus Murrenhoff
Keyword(s):  
Friction And Wear ◽  
Public Awareness ◽  
Viscosity Index ◽  
Test Facility ◽  
Ecological Requirements ◽  
Hydrodynamic Behaviour ◽  
Mixed Friction ◽  
Essential Components ◽  
Hydraulic Fluids ◽  
The Impact

Hydraulic systems are used in many technical applications, e.g. in agricultural and forestry machines. Hydrostatic pumps and engines as well as hydraulic fluids are essential components of these systems. Thereof, the hydraulic fluids are of great importance since not only technical but also ecological requirements have to be fulfilled. Apart from fluid power transmission the most important technical function of hydraulic fluids is lubrication and the resulting reduction of friction and wear. In times when saving energy and resources have become environmental matters, lubricants are increasingly attracting public awareness. Important ecological aspects which need to be considered since they have a major impact on the application of technical products and decide about their success are biodegradability, water pollution and ecological toxicity. This is why ester based hydraulic fluids have started to substitute mineral oil based fluids. Additionally, ester based fluids have excellent tribological features due to the polarity of the ester molecules. However, ester based fluids change their physical and chemical properties due to usage. This paper will show that both the total acid number and the viscosity is increased by ageing while the level of additives and the viscosity index is decreased. Therefore, the impact of ageing on the tribological performance of an ester based hydraulic fluid will be analysed by friction and wear investigations. Exemplary, two tribological contacts are chosen: a mixed friction and an elasto-hydrodynamic contact. These are representative conditions for hydrostatic pumps and engines. Analysing the fluid’s behaviour being stressed by mixed friction is performed by using a tribometer. Investigating the ageing impact on elasto-hydrodynamic behaviour of the fluid, a bearing test facility is used. Finally, after having been dealing with tribological contacts used in hydrostatic machines the performance of a hydrostatic machine itself will be analysed. The impact of increased viscosity on friction which is generated within a hydrostatic gear unit at low speed will be discussed.

Effects of Quarantine Due to the COVID-19 on Sleep Duration and Quality in Algerians

2020 ◽  
Vol 60 (2) ◽  
pp. 182-193
Author(s):  
Kacem Abdelhadi ◽  
Houar Abdelatif ◽  
Zerf Mohamed ◽  
Bengoua Ali
Keyword(s):  
Statistical Analysis ◽  
Sleep Quality ◽  
Sleep Duration ◽  
Online Survey ◽  
Public Awareness ◽  
Italian Version ◽  
Sleep Timing ◽  
Algerian Population ◽  
Significant Change ◽  
The Impact

SummaryThis study tests the impact of COVID-19 on sleep of Algerian population before and during the COVID-19 quarantine by an estimated online survey, adapted from the PSQI Italian version. Including 1210 participants (age between 18-60 years old). The statistical analysis was carried out using SPSS version 22.0 software. Our results showed a significant change in sleeping quality during quarantine, the sleep timing markedly changed, we also noticed additional use of sleeping medications. Algerian scientists recommend to build public awareness and to provide necessary information regarding Algerian sleep quality, especially for Algerian adults.

scholarly journals Anthropomorphic Strategies Promote Wildlife Conservation through Empathy: The Moderation Role of the Public Epidemic Situation

2021 ◽  
Vol 18 (7) ◽  
pp. 3565
Author(s):  
Dan Yue ◽  
Zepeng Tong ◽  
Jianchi Tian ◽  
Yang Li ◽  
Linxiu Zhang ◽  
...  
Keyword(s):  
College Students ◽  
Behavioral Intention ◽  
Wildlife Conservation ◽  
Negative Emotion ◽  
Public Awareness ◽  
Negative Emotions ◽  
Experimental Studies ◽  
Wildlife Trade ◽  
Illegal Wildlife Trade ◽  
The Impact

The global illegal wildlife trade directly threatens biodiversity and leads to disease outbreaks and epidemics. In order to avoid the loss of endangered species and ensure public health security, it is necessary to intervene in illegal wildlife trade and promote public awareness of the need for wildlife conservation. Anthropomorphism is a basic and common psychological process in humans that plays a crucial role in determining how a person interacts with other non-human agents. Previous research indicates that anthropomorphizing nature entities through metaphors could increase individual behavioral intention of wildlife conservation. However, relatively little is known about the mechanism by which anthropomorphism influences behavioral intention and whether social context affects the effect of anthropomorphism. This research investigated the impact of negative emotions associated with a pandemic situation on the effectiveness of anthropomorphic strategies for wildlife conservation across two experimental studies. Experiment 1 recruited 245 college students online and asked them to read a combination of texts and pictures as anthropomorphic materials. The results indicated that anthropomorphic materials could increase participants’ empathy and decrease their wildlife product consumption intention. Experiment 2 recruited 140 college students online and they were required to read the same materials as experiment 1 after watching a video related to epidemics. The results showed that the effect of wildlife anthropomorphization vanished if participants’ negative emotion was aroused by the video. The present research provides experimental evidence that anthropomorphic strategies would be useful for boosting public support for wildlife conservation. However, policymakers and conservation organizations must be careful about the negative effects of the pandemic context, as the negative emotions produced by it seems to weaken the effectiveness of anthropomorphic strategies.

scholarly journals Fate of unproductive and unattractive habitats: recent changes in Iberian steppes and their effects on endangered avifauna

2006 ◽  
Vol 33 (3) ◽  
pp. 223-232 ◽  
Author(s):  
PAOLA LAIOLO ◽  
JOSÉ L. TELLA
Keyword(s):  
Primary Productivity ◽  
Western Europe ◽  
Agricultural Development ◽  
Public Awareness ◽  
Species Dispersal ◽  
Ecological Value ◽  
Shrub Steppe ◽  
Steppe Birds ◽  
Dupont’S Lark ◽  
The Impact

Steppe ecosystems worldwide are affected by agricultural development and generally unprotected. Spanish shrub-steppes contain endangered avifauna, and this paper analyses their state of habitat conservation, the changes that have occurred in the last decade, primary productivity and its relationship with land exploitation and the richness of threatened birds, and avifauna responses to habitat loss. Fifty steppe remnants distributed throughout Spain and inhabited by Dupont's lark Chersophilus duponti, an endangered passerine representative of shrub steppe-like habitat, were studied. The study fragments were generally affected by agriculture exploitation, and steppe cover had significantly decreased in several isolated patches during the period 1991–1999. Steppe habitat recovered slightly in areas with low plant productivity indices, and decreased in extent in the most productive areas, in line with EU (European Union) agricultural policy recommendations to abandon marginal land of low productivity. The low overall primary productivity of Iberian steppes opened the way to industrial activities (mining, waste collection and wind-farming), which in the study areas occurred more frequently in steppe than in other habitat types that are more attractive to the public (woodland) or more productive (farmland). The emerging wind industry little affected the study plots, but the presence of anemometers suggests that the impact is likely to increase in the near future, especially in the largest steppelands. Dupont's lark was sensitive to the fragmentation of its habitat; crowding occurred in isolated and small fragments, possibly as a consequence of habitat constraints and species dispersal dynamics. Fragments inhabited by Dupont's lark also hosted other steppe birds with a high conservation value; the community of endangered birds, mostly adapted to arid conditions, was richest in the less productive sites. Only four shrub-steppe fragments are given some kind of protection throughout Spain, testifying to the limited public awareness about the value of this habitat. Urgent action is required to restore this habitat through abandonment of less productive farmland, and to create a network of protected and connected steppelands, in order to assure the long-term viability of steppe specialists and the preservation of a habitat that is unique in Western Europe. This should be coupled to an effort to increase social consciousness of the ecological value of steppes and arid landscapes in general.

Abstract P99: Impact of the Covid-19 Pandemic on Stroke Thrombolysis Rate and Delay to Thrombolysis Treatment in a Regional Stroke Centre in London, UK

Stroke ◽  
2021 ◽  
Vol 52 (Suppl_1) ◽  
Author(s):  
Brian Drumm ◽  
Paul Bentley ◽  
Zoe Brown ◽  
Lucio D’Anna ◽  
Tsering Dolkar ◽  
...  
Keyword(s):  
Arrival Time ◽  
Negative Impact ◽  
Public Awareness ◽  
Stroke Severity ◽  
Time Intervals ◽  
Neurological Outcomes ◽  
Stroke Thrombolysis ◽  
Prehospital Delays ◽  
The Impact ◽  
Stroke Centre

Introduction: There are reports of changes in the numbers of stroke admissions and time intervals to receiving emergency treatments during the COVID-19 pandemic. We examined the impact of the COVID-19 pandemic on the stroke thrombolysis rate and delay to thrombolysis treatment in a regional stroke centre in London, UK. Methods: COVID-19 testing began at our hospital on 3 March 2020. Clinical data for all acute stroke admissions were routinely collected as part of a national Sentinel Stroke National Audit Programme (SSNAP) and all thrombolysis data were entered into our local thrombolysis database. We retrospectively extracted the relevant patient data for the period of March to May 2020 (COVID group) and compared to the same period in 2019 (pre-COVID group). Results: Compared with pre-COVID, there was a 17.5% fall in total stroke admissions (from 315 to 260) during COVID; but there were no significant differences in the demographics, stroke severity, proportions with known time of onset, or median onset-to-arrival time. The thrombolysis rates amongst ischemic strokes were not significantly different between the two groups (59/260=23% pre-COVID vs. 41/228=18% COVID, p=.19). For thrombolysis patients, their stroke severity and demographics were similar between the two both groups. Median onset-to-needle time was significantly longer by 22 minutes during COVID [127 (IQR 94-160) vs. 149 (IQR 110-124) minutes, p=.045]; this delay to treatment was almost entirely due to a longer median onset-to-arrival time by 16 minutes during COVID (p=.029). Favorable early neurological outcomes post-thrombolysis (defined as an improvement in NIHSS by ≥4 points at 24 hours) were similar (45% vs. 46%, p=.86). Conclusion: COVID-19 pandemic had a negative impact on prehospital delays which in turn significantly increased onset-to-needle time, but without affecting the chance of a favorable early neurological outcome. Our data highlight the need to maintain public awareness of taking immediate action when stroke symptoms occur during the COVID-19 pandemic.

Review of the impact Covid-19 has on the Psychosocial factors affecting Well-Being

2021 ◽  
pp. 3404-3408
Author(s):  
Sheila Menon FBSCH ◽  
Vidya Bhagat
Keyword(s):  
Psychosocial Factors ◽  
Health Workers ◽  
Public Awareness ◽  
Cost Effective ◽  
Well Being ◽  
Security Measures ◽  
Post Traumatic Stress ◽  
Negative Effects ◽  
Factors Affecting ◽  
The Impact

The COVID-19 pandemic has had a significant impact on the psychosocial factors that effect people globally. Particularly affected are children, students and health workers and the common symptoms identified are stress, anxiety disorders, depression and post-traumatic stress disorder. In addition, the various security measures implemented to ensure public safety have adversely affected relationships between people. This study directs public awareness to the value of psychotherapeutic support. Tele-therapy can be offered easily to people both at home or in the workplace, providing both cost effective and time sensitive solutions during times of crisis. The current review article provides an overview of the importance of maintaining psychological well-being during a pandemic and the identifies the role that empathetic communication has on wellbeing. The literature review was completed using electronic databases such as PubMed, Medline, and Scopus databases using the keywords covid-19, affected groups, affected relationships, psychology and its technological interventions, negative effects of pandemic so on.

Interaction of Shroud Leakage Flow and Main Flow in a Three-Stage LP Turbine

2003 ◽  
Vol 127 (4) ◽  
pp. 649-658 ◽  
Author(s):  
Jochen Gier ◽  
Bertram Stubert ◽  
Bernard Brouillet ◽  
Laurent de Vito
Keyword(s):  
Main Flow ◽  
Secondary Flows ◽  
Test Facility ◽  
Navier Stokes ◽  
Leakage Flow ◽  
Jet Engines ◽  
Flow Interactions ◽  
Lp Turbine ◽  
The Impact ◽  
The Ideal

Endwall losses significantly contribute to the overall losses in modern turbomachinery, especially when aerodynamic airfoil load and pressure ratios are increased. In turbines with shrouded airfoils a large portion of these losses are generated by the leakage flow across the shroud clearance. Generally the related losses can be grouped into losses of the leakage flow itself and losses caused by the interaction with the main flow in subsequent airfoil rows. In order to reduce the impact of the leakage flow and shroud design related losses a thorough understanding of the leakage losses and especially of the losses connected to enhancing secondary flows and other main flow interactions has to be understood. Therefore, a three stage LP turbine typical for jet engines is being investigated. For the three-stage test turbine 3D Navier-Stokes computations are performed simulating the turbine including the entire shroud cavity geometry in comparison with computations in the ideal flow path. Numerical results compare favorably against measurements carried out at the high altitude test facility at Stuttgart University. The differences of the simulations with and without shroud cavities are analyzed for several points of operation and a very detailed quantitative loss breakdown is presented.

Elements in the development of conservation plans for Atlantic salmon (Salmo salar)

1998 ◽  
Vol 55 (S1) ◽  
pp. 312-323 ◽  
Author(s):  
Julian J Dodson ◽  
R John Gibson ◽  
Richard A Cunjak ◽  
Kevin D Friedland ◽  
Carlos Garcia de Leaniz ◽  
...  
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Size Structure ◽  
Public Awareness ◽  
Biological Information ◽  
Conservation Unit ◽  
Atlantic Salmon Salmo Salar ◽  
Conservation Plan ◽  
Conservation Plans ◽  
The Impact

This paper examines two areas to be considered in developing conservation plans for Atlantic salmon (Salmo salar): goal statements and the general framework for the implementation of a conservation plan. From a biological perspective, the appropriate conservation unit for Atlantic salmon is the Evolutionary Significant Unit (ESU). As conservation decisions will rarely be based solely on biological information, the Operational Conservation Unit (OCU) is defined as resulting from the interplay between biological requirements and socio-economic issues. A multi-scale habitat inventory of Atlantic salmon rivers to know what their status is relative to historical conditions is the first step in a functional conservation plan. The viability of salmon populations may be assessed according to 6 variables: abundance, resilience, age and size structure, sex ratio, spatial and geographical distribution. A genetically viable population possesses the species' evolutionary legacy and the genetic variation on which future evolutionary potential depends. Four factors important to monitoring changes in a population's genetic health are genetic diversity, effective population size, genetic bottlenecks and founder effects and gene flow. Implementation of a conservation plan must be proactive to maintain the quality of the OCUs. Commercial and recreational fisheries need to be limited and several case studies are reviewed. The importance of avoiding the introduction of exotics and minimizing the impact of sampling methodology, as well as the pitfalls of planting eggs, fry, or parr, are addressed. Finally, the importance of fostering public awareness of the value of conservation is essential to apply the political pressure necessary to preserve natural resources.

scholarly journals Prevalence and mitigation of aflatoxins in Kenya (1960-to date)

2018 ◽  
Vol 11 (3) ◽  
pp. 341-357 ◽  
Author(s):  
C.K. Mutegi ◽  
P.J. Cotty ◽  
R. Bandyopadhyay
Keyword(s):  
Public Awareness ◽  
Control Measures ◽  
Learning Networks ◽  
Management Options ◽  
Adverse Health Effects ◽  
Documented Information ◽  
Food And Feed ◽  
Safe Food ◽  
Long Term Impact ◽  
The Impact

Aflatoxins are highly toxic metabolites of several Aspergillus species widely distributed throughout the environment. These toxins have adverse effects on humans and livestock at a few micrograms per kilogram (μg/kg) concentrations. Strict regulations on the concentrations of aflatoxins allowed in food and feed exist in many nations in the developing world. Loopholes in implementing regulations result in the consumption of dangerous concentrations of aflatoxins. In Kenya, where ‘farm-to-mouth’ crops become severely contaminated, solutions to the aflatoxins problem are needed. Across the decades, aflatoxins have repeatedly caused loss of human and animal life. A prerequisite to developing viable solutions for managing aflatoxins is understanding the geographical distribution and severity of food and feed contamination, and the impact on lives. This review discusses the scope of the aflatoxins problem and management efforts by various players in Kenya. Economic drivers likely to influence the choice of aflatoxins management options include historical adverse health effects on humans and animals, cost of intervention for mitigation of aflatoxins, knowledge about aflatoxins and their impact, incentives for aflatoxins safe food and intended scope of use of interventions. It also highlights knowledge gaps that can direct future management efforts. These include: sparse documented information on human exposure; few robust tools to accurately measure economic impact in widely unstructured value chains; lack of long-term impact studies on benefits of aflatoxins mitigation; inadequate sampling mechanisms in smallholder farms and grain holding stores/containers; overlooking social learning networks in technology uptake and lack of in-depth studies on an array of aflatoxins control measures followed in households. The review proposes improved linkages between agriculture, nutrition and health sectors to address aflatoxins contamination better. Sustained public awareness at all levels, capacity building and aflatoxins related policies are necessary to support management initiatives.

scholarly journals CORRELATION BETWEEN SMOKE-FREE AREAS AND SMOKING BEHAVIOR IN INDONESIA

2020 ◽  
Vol 8 (2) ◽  
pp. 117
Author(s):  
Mohamad Anis Fahmi
Keyword(s):  
Public Awareness ◽  
Smoking Behavior ◽  
Secondary Data ◽  
Computer Application ◽  
P Value ◽  
Cross Sectional ◽  
Positive Correlation ◽  
The Government ◽  
Cross Sectional Design ◽  
The Impact

Background: Low public awareness of the impact of smoking makes the implementation of smoke-free areas (KTR) difficult. Smoke-free areas aim to protect the public from the direct and indirect effects of smoking. Purpose: This study aimed to analyze the correlation between the application of smoke-free areas and the prevalence of active and ex-smokers in Indonesia. Method: This study implemented a cross-sectional design, using secondary data from the Riskesdas 2018 on active and ex-smokers. KTR application data were obtained from the Profile of Non-Communicable Diseases in 2016. A Pearson product-moment test was conducted by a computer application to determine the correlation coefficient (r). This coefficient was used to describe the level of correlation between the two variables; significance was determined as a p value of 5%. Results: This study showed that the average application of KTR throughout Indonesia was 50.83%, active smokers comprised 23.49% of the population, and ex-smokers comprised 4.94%. Most active smokers were in Java and Sumatra, while the majority of ex-smokers were in Java and Sulawesi and the majority of KTR was in Java. This study shows that there is a positive correlation between KTR application and the percentage of ex-smokers (r = 0.46; p value = 0.01). Conclusion: There is a positive correlation between the application of KTR and an increase in ex-smokers. The government needs to increase the application of KTR policies.

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