bluuebunny/crossref_metadata_2025 huggingface dataset:
Supply the demand: Assessment of the feasibility of local non-urologists in relieving the burden of chronic indwelling catheters in a low-income country
Authors: Bobrowski Adam , Nayan Madhur , Heimrath Olivier , Goche Duncan , Ludzu Enok , Singal Rajiv K.
Published: October 2020

Introduction: Despite the high prevalence rates of urinary retention in sub-Saharan Africa, regional deficiencies in urological care have culminated in inadequate medical management, and a backlog of urology cases. Our study examined the efficacy and safety of a surgical camp enlisting local non-urologists performing simple open prostatectomy on the rate of chronic catheter usage secondary to urinary retention.

Methods: We reported on a prospective case series of patients with chronic indwelling catheters who underwent open simple prostatectomy during a one-week urology camp in the Machinga District of Malawi. All operations were performed by a locally trained general surgeon and a clinical officer.

Results: Twenty-three (47.9%) of 48 male patients with urinary retention assessed for eligibility for open simple prostatectomy were deemed eligible and underwent the procedure. Of the patients who underwent an open simple prostatectomy, histopathological findings demonstrated benign prostatic hyperplasia in 19 patients (82.6%), while six patients (26.1%) had coincidental malignancy. At postoperative followup, the entire cohort was catheter-free and reported regular sexual activity and the ability to return to work, while 87.0% noted improvements in social integration and 34.8% cited higher self-esteem. Two patients required treatment for infection and one patient experienced fascial dehiscence. Two months following prostatectomy, all patients were catheter-free and able to void independently.

Conclusions: Local surgical practitioners without formal urology training can successfully perform open simple prostatectomy to relieve patients of chronic indwelling catheters and assist in addressing the disease burden in a low-resource setting.
What is the relationship of stress to patients' kidney stone-related quality of life?
Authors: Lundeen Colin , Lim Jonathan R.Z. , Scotland Kymora B. , Ardekani Reza Safaee , Penniston Kristina L. , Streeper Necole M. , Chi Thomas , Landman Jaime , Viprakasit Davis P. , Chew Ben H.
Published: October 2020

Introduction: Health-related quality of life (HRQOL) is decreased in patients with kidney stones at all stages of stone disease, even when asymptomatic. Stress is thought to contribute to HRQOL, although there has been minimal investigation into the effect of stress on stone-related quality of life (QOL). We used the Wisconsin Stone Quality of Life Questionnaire (WISQOL) to assess the relationship of stress to stone-related QOL in kidney stone patients.

Methods: As part of the WISQOL Research Consortium, patients were approached in outpatient clinics and completed the WISQOL and the Perceived Stress Scale 10-item questionnaire (PSS-10). Patients with stones at enrollment were divided into those with symptoms and those without, while patients with no current stones formed another group. Questionnaire scores from each group were compared statistically and correlations between the groups were calculated.

Results: Patients (n=704) were enrolled from six centers. The WISQOL successfully discriminated between patients with current stones and those without (p<0.0001), while the PSS-10 did not (p=0.0869). The PSS-10 revealed patients with symptomatic kidney stones experienced higher levels of general stress than asymptomatic subjects (p<0.0001). However, a Pearson correlation test comparing the responses from each instrument revealed no overall correlation between general stress and HRQOL (r=0.05).

Conclusions: Symptomatic kidney stones increase general stress, as these patients demonstrate higher PSS-10 scores. Despite this, no correlation exists between general stress and stone-related QOL in patients with stone disease regardless of their stone and symptom status. This implies the existence of other factors impacting QOL in these patients, which warrants further exploration.
Sperm retrieval and intracytoplasmic sperm injection outcomes with testicular sperm aspiration in men with severe oligozoospermia and cryptozoospermia
Authors: Alharbi Mohannad , Almarzouq Ahmad , Zini Armand
Published: October 2020

Introduction: Several studies addressed the role of testicular sperm aspiration with intracytoplasmic sperm injection (ICSI) in azoospermic men but few have included non-azoospermic men. The aim of this study was to evaluate testicular sperm aspiration (TESA) sperm retrieval rates and ICSI outcomes in men with severe oligozoospermia.

Methods: Data were collected retrospectively from 88 consecutive, non-azoospermic, infertile men with idiopathic severe oligozoospermia who underwent TESA between January 2011 and January 2018. Patients were categorized into four groups according to sperm concentration: <5 and >1 million/ml (group 1), <1 and > 0.1 million/ml (group 2), <0.1 million/ml (group 3) and cryptozoospermia (group 4).

Results: Mean male age was 37±7 years and the mean female age was 33±4 years. Sperm was recovered successfully in 90% (79/88) of the men overall and in 100% (30/30) of the men in group 1, 97% (29/30) of the men in group 2, 88% (15/17) of the men in group 3, and 45% (5/11) of the men in group 4. Most (65%, 57/88) of the couples had an embryo transfer (ET). The overall clinical pregnancy rate per ET was 46% (26/57). The clinical pregnancy rates (per ET) were 43% (9/21) in group 1, 65% (13/20) in group 2, 36% (4/11) in group 3 and 0% (0/5) in group 4.

Conclusions: Our data indicate TESA allows for high sperm retrieval rates and acceptable ICSI pregnancy rates in men with severe oligozoospermia. However, in our experience, TESA sperm retrieval rates and ICSI outcomes are poor in cryptozoospermic men.
Permeability evaluation of gemcitabine-CPP6 conjugates in Caco-2 cells
Authors: Ferreira Abigail , Moreira Sara , Lapa Rui , Vale Nuno
Published: October 2020

Cancer is one of the most alarming diseases due to its high mortality and still increasing incidence rate. Currently available treatments for this condition present several shortcomings and new options are continuously being developed and evaluated, aiming at increasing the overall treatment efficiency and reducing associated adverse side effects. Gemcitabine has proven activity and is used in chemotherapy. However, its therapeutic efficiency is limited by its low bioavailability as a result of rapid enzymatic inactivation. Additionally, tumor cells often develop drug resistance after initial tumor regression related to transporter deficiency. We have previously developed three gemcitabine conjugates with cell-penetrating hexapeptides (CPP6) to facilitate intracellular delivery of this drug while also preventing enzymatic deamination. The bioactivity of these new prodrugs was evaluated in different cell lines and showed promising results. Here, we assessed the absorption and permeability across Caco-2 monolayers of these conjugates in comparison with gemcitabine and the respective isolated cell-penetrating peptides (CPPs). CPP6-2 (KLPVMW) and respective Gem-CPP6-2 conjugate showed the highest permeability in Caco-2 cells.
The effect of pro-, pre- and synbiotics on the health of mink, morphometric parameters of their digestive tract, and microbiological analysis of its contents
Authors: Piórkowska Małgorzata
Published: October 2020

The aim of the study was to analyse the effect of selected feed additives (pro-, pre- and synbiotics) on the health of mink, morphometric parameters of their digestive tract, and microbiological identification of its contents. The observations were made on pastel mink assigned to the following dietary treatments: group I – standard farm feed without supplements, group II – probiotic-supplemented feed, group III – prebiotic-supplemented feed, and group IV – synbiotic-supplemented feed. The feed additives were found to affect the growth and weight gains of the mink. Body weight at winter fur priming ranged from 1.45 to 2.54 kg in females and from 2.70 to 4.20 kg in males. During the rearing period (weaning to slaughter), the highest weight gains were observed in the group receiving prebiotics – on average 760 g in females and 1970 g in males. Analysis of the morphometric parameters of the digestive tract showed highly significant differences between means for the groups, except for the weight of the lungs and spleen and the length of the stomach. The mean concentration of total bacteria in the intestinal contents was similar in groups II and III (8.5-9.4 x 104 CFU/g), higher in group IV, and highest in the control group (5.9 x 106 CFU/g). Among the bacteria identified, Corynebacterium was dominant in all groups. The total fungal count in the intestinal contents was lowest in the mink receiving prebiotics. The dominant fungi were Candida, particularly Candida glabrata. The proportion of fungi of this genus varied between groups from 84.5% to 89.5%. The other fungi identified in the digesta were Rhizopus spp. and Aspergillus spp.
Developmental anomalies in ide (Leuciscus idus L.) larvae caused by copper and cadmium
Authors: Ługowska Katarzyna , Kondera Elżbieta
Published: October 2020

Ide embryos were incubated in 0.1 mg dm3 of Cu or Cd or in clean tap water (control). Both metals significantly decreased swelling of eggs. They reduced the rate of embryonic development and the hatching rate. Six types of body malformations were found in newly hatched larvae: spine curvature, C-shaped body, head deformation, yolk sac deformation, heart oedema, and reduced body length. Only the first two types of deformations were observed in the control, while more severe malformations were found following Cu and Cd exposure. Copper exerted a detrimental effect mainly during embryogenesis (egg swelling and rate of development), while the toxic effects of cadmium were more significant in newly hatched larvae. Larval body deformities may be used as a bioindicator of water pollution with heavy metals.
Music As Translation. Musical Motifs in Liebert’s Poetry
Authors: Papierski Maciej
Published: October 2020

This article is devoted to analyses of musical motifs in poetry by a Polish author Jerzy Liebert
(1901–1934). Two main kinds of metaphorically understood music can be distinguished in his
work: the earthly, referring to human fi niteness, and the transcendental, which is the divine music
of God. In the investigation of this problem, Boethian typology of music (musica mundana, musica
instrumentalis, musica humana) is engaged. The results of these analyses contribute to the understanding of how the human condition confronts the perfect nature of the Creator in Liebert’s poetry.
The article argues that musical motifs seem to be yet another expression of this problem, ubiquitous
in the poet’s work; thus, they are essential to its correct interpretation.
Between “full moon and summer solstice”.
The quest for transcendence in the poetry of Andrzej Busza
Authors: Skolik Joanna
Published: October 2020

The article is an attempt to describe the poet’s vision of human destiny, history and transcendence. Analysing poems from two poetry volumes I endeavour to present Busza’s philosophy.
The poet notes and appreciates science and scientifi c achievements as well as civilisational development, although he realises that they may be dangerous for human spirituality and potentially
lead to catastrophe.
The aesthetics of the religious
and the sacralization of “positivist” science – “idealism” (Adam Asnyk)
and decadent religious poetry of early modernism
(Stanisław Korab-Brzozowski)
Authors: van Nieukerken Arent
Published: October 2020

Religious images and motives in nineteenth-century poetry (particularly in the period of dominant Positivism) became gradually aestheticized and lost much their original symbolic impact. This
was partly due to the consequences of Kantian philosophy that introduce a dichotomy between phenomena and noumena. Positivism was merely interested in the relation between objects belonging
to the phenomenal world. Critical theology (D.F. Strauss, Ernest Renan) started to analyze religious
symbols and New Testament stories from the point of view of history and (compared) myth, applying positivist methodology to the “humanities”. Poets wishing to recapture the religious potential
(the “Holy”) of traditional symbols and ritual had to recontextualize them. The “sacred” does not
reside in the symbols themselves, but it is transferred to the relation established by the individual
between his position in the world and a symbol or ritual. The religious moment results from experiencing this “unrepeatable” relation (its unrepeatability being the condition of contact with transcendence, relating the symbol as phenomenon with the noumenal sphere that is present as a trace
– the individually experienced symbol points to its absence).
In Polish late romantic poetry (e.g. Adam Asnyk) the individualization of the experience of transcendence is impeded by the patriotic connotations of religious symbols and rituals that presuppose
the experience of belonging to a (“national”) community (a “relic” of Polish romantic messianism,
c.f. the aftermath of the January Uprising). The modernist poet Stanisław Korab Brzozowski succeeded in developing a poetic method of recontextualizing traditional religious symbols that allowed to show the incompatibility between the phenomenal and the noumenal sphere as an inner
experience of a subject (e.g. a wooden cross stretching its arms to an empty heaven) as a direct
reaction to Renan´s relativization of the Christian “Heilsgeschichte”, unmediated by Polish romantic
messianism).
Time-Series Prediction for Amount of Airworthiness Based on Time-Delay Neural Networks
Authors: Tatli Ali , Kahvecioglu Sinem , Karakoc Hikmet
Published: October 2020

Troposphere and the first stratum of the stratosphere are intensely utilized atmosphere layers for the aviation activities. Due to the different performances, capabilities, designs, and equipment of the aerial vehicles, meteorological weather events that occur in the troposphere affect these vehicles at different levels during their aeronautical activities. Although simple aircrafts are more sensitive to the effects of meteorological events, they are especially preferred by flight training organizations (FTOs) in pilotage training when they are considered in terms of maintenance and equipment costs. In cases where inexperienced pilot candidates and simple aircrafts that are more vulnerable to weather events come together, analysis and prediction of meteorological parameters becomes more important in terms of preventing accidents and reducing risks, as well as proper planning for flight and maintenance. The purposes of this study are, first, to derive flight availability time-series for two different types of aircraft according to visual flight rules by using Meteorological Terminal Air Report (METAR), and then to establish and evaluate a prediction model by using Time-Delay Neural Networks (TDNNs).
Die Sanktionierung missbräuchlicher Vertragsklauseln sowie die Vertragsrückabwicklung am Beispiel Polens
Authors: Karasek-Wojciechowicz Iwona
Published: October 2020

In recent years, the European Court of Justice has often dealt with disputes revolving around the interpretation of Council Directive 93/13/EEC of 5 April 1993 on unfair terms in consumer contracts. This article focuses on controversial questions in the domains of legal doctrine and jurisdiction, in particular in the context of disputes over foreign-currency denominated or foreign-currency indexed loans. It discusses questions revolving around legal bases for reverse transactions following the invalidity of a contract, the lack of legal bases for performing a contract, jurisdiction on the invalidity of a contract in the case of unfair terms, without which the contract cannot be concluded, the extent of reverse transactions, ECJ jurisdiction, the Council Directive’s deterrent effect, the admissibility of substitute types of fulfilling the contract, and consumer claims against financial institutions.
Kroatische Verbraucher vs. Kredite in CHF – ein Drama in fünf Akten ohne Schlussakt
Authors: Josipović Tatjana
Published: October 2020

The difficult financial and social position of Croatian consumers with CHF loans was a trigger for various reactions and measures by the Croatian legislator and Government, as well as consumers themselves. An array of legislative and administrative measures was passed to alleviate the financial and social position of consumers with CHF loans. Various legislative measures were also passed that were intended to alleviate the position of consumers in foreclosures on residential real property. Finally, consumers have started to initiate, without waiting for the legislator to pass legislation, proceedings in order to protect individual and collective interests of consumers with CHF loans. This article depicts the development of case law with respect to the protection of collective interests of consumers with CHF loans. It analyses the mutual influences between case law and ad hoc consumer protection legislation (e.g. a conversion of CHF loans into EUR loans). It comments on the opinions of courts related to the criteria for evaluating the unfairness of foreign currency clauses and the provisions on variable interest rates in the context of protecting collective consumer interests. It points to problems, within the context of collective consumer protection, stemming from legislative loopholes in the relationship between collective and individual consumer protection, and legislative loopholes in particular ad hoc measures for protecting consumers via converting CHF loans into EUR loans. The paper should warn of problems arising in subsequent coordination of various measures taken in order to protect the interest of consumers with the development of case law in that area.
Centring LGBT2QIA+ Subjects in Knowledge Organization Systems
Authors: Bullard Julia , Dierking Amber , Grundner Avi
Published: October 2020

This paper contains a report of two interdependent knowledge organization (KO) projects for an LGBT2QIA+ library. The authors, in the context of volunteer library work for an independent library, redesigned the classification system and subject cataloguing guidelines to centre LGBT2QIA+ subjects. We discuss the priorities of creating and maintaining knowledge organization systems for a historically marginalized community and address the challenge that queer subjectivity poses to the goals of KO. The classification system features a focus on identity and physically reorganizes the library space in a way that accounts for the multiple and overlapping labels that constitute the currently articulated boundaries of this community. The subject heading system focuses on making visible topics and elements of identity made invisible by universal systems and by the newly implemented classification system. We discuss how this project may inform KO for other marginalized subjects, particularly through process and documentation that prioritizes transparency and the acceptance of an unfinished endpoint for queer KO.
Weisheit in der Führung »revisited«: Wie aktuell ist der Weisheitsbegriff im digitalen Zeitalter?
Authors: Wagner Ursula
Published: October 2020

In der empirischen Studie »Weisheit im Management« (Wagner 2013) konnte Weisheit über einen Fragebogen empirisch definiert und an einer Stichprobe von 408 Führungskräften statistisch validiert werden. Die Ergebnisse von 2013 werden vorgestellt und ihre Bedeutung für Themen von Organisation und Führung im Zeitalter der Digitalisierung exploriert. Während die Aspekte von Weisheit, wie sie in der Wissenschaft erforscht wurden, relevanter denn je für Führung sind, wird »Weisheit« als Begriff im Volksmund nicht mit den Themen der Digitalisierung in Verbindung gebracht. Als Resümee schlägt die Autorin daher vor, den Begriff der »Weisheit in der Führung« entweder durch »holistische Führung« zu ersetzen oder Weisheit in den sozialen Netzwerken zeitgemäß und neu zu erklären.
Wie gelingt Onlinemediation?
Authors: Rickert Anne
Published: October 2020

Ist Mediation in Präsenz, ein Zusammentreffen im physischen Raum, unter bestimmten Umständen nicht möglich, stellt die Durchführung des Mediationsverfahrens im virtuellen Raum eine interessante Alternative dar, ohne die eine Mediation sonst überhaupt nicht stattfinden könnte. Für den erfolgreichen Prozess ist unabdingbar, dass der/die Mediator*in mit den Besonderheiten der Onlinekommunikation souverän umzugehen weiß. Hierzu gibt der Artikel wichtige Tipps und Hinweise für angehende Onlinemediator*innen.
Current Mesothelioma Treatment and Future Perspectives
Authors: Štrbac Danijela , Goričar Katja , Kovač Viljem , Dolžan Vita
Published: October 2020

The established treatments in malignant mesothelioma are based on trimodality approach including surgery, radiation and chemotherapy. Such approach has proved to clinically benefit mesothelioma patients, however the current treatments seem to have reached a limit regarding the survival and disease control. One approach to overcome the limitations of current treatments is focused on finding appropriate serum or genetic biomarkers that could support personalized medicine and improve outcomes with established treatment modalities in mesothelioma patients. The other approach is exploiting better understanding of molecular and genetic characteristics of mesothelioma to search for new treatment modalities. Immunotherapy with anti PD-1, PD-L1 and CTLA-4 agents is a new frontier in mesothelioma treatment. As in many solid tumors, CAR-T cell therapy is emerging from the field of hematological malignancies. Immunomodulatory approaches seem to be a new perspective in treatment of malignant mesothelioma. This chapter aims to explore possible new therapeutic approaches in mesothelioma.
Assessment of Ecological Disturbance Caused by Flood and Fire in Assam Forests, India, Using MODIS Time Series Data of 2001-2011
Authors: Dutta Dibyendu , Balha Akanksha , Kumar Das Prabir , Jain Pragyan , Lukose Libeesh , Akram Wasim
Published: October 2020

The forest area of Assam State is known for its rich biodiversity. In the present study, the disturbance regime within the Assam forest area caused by periodic flood and forest fire, was assessed using the Moderate Resolution Imaging Spectroradiometer (MODIS) time-series (2001–2011) data. The MODIS Global Disturbance Index (MGDI) images were generated using MODIS derived Enhanced Vegetation Index (EVI) and Land Surface Temperature (LST) images. The temporal intensity of flood and forest fire in sixteen representative forests was analyzed to develop the MGDI based thresholds for detecting the disturbed area. The threshold for the non-instantaneous disturbance, i.e. flood, was found to be 107% whereas it was 111% for instantaneous disturbance, i.e. forest fire. The thresholds were applied on the MGDI images to delineate disturbed caused by flood and fire, separately for each year. The time-series disturbance areas were integrated over the years (2001–2011) to generate the classified disturbance prone maps.
Community with Nothing in Common?
Authors: Sentesy Mark ,   Philosophy Documentation Center
Published: October 2020

The Protagoras examines how community can occur between people who have nothing in common. Community, Protagoras holds, has no natural basis. Seeking the good is therefore not a theoretical project, but a matter of agreement. This position follows from his claim that “man is the measure of all things.” For Socrates community is based on a natural good, which is sought through theoretical inquiry. They disagree about what community is, and what its bases and goals are. But Plato illustrates the seriousness of Protagoras’s position through the repeated breakdown of their conversation. The dialogue leads us to question both speakers’ assumptions about community. Socrates must face the problem that not everything can be brought to language. Protagoras must recognize that there is a basis of community even in what cannot be shared. Community is grounded in an event that is both natural and not up to us, and cultural and articulate.
Unauthorized Immigrants, Reasonable Expectations, and the Right to Regularization
Authors: Carnes Thomas S. ,   Department of Philosophy, Florida State University
Published: October 2020

This article brings an account of reasonable expectations to bear on the question of when unauthorized immigrants have a right to be regularized—that is, to be formally guaranteed freedom from the threat of deportation. Contrary to the current literature, which implicitly relies on a flawed understanding of reasonable expectations, this article argues that only those unauthorized immigrants who have both been tacitly permitted by the state despite lacking formal authorization and have remained long enough to develop deep social roots in the state have a right to regularization.
The Benefits and Challenges of Point-of-Care Testing in Rural and Remote Primary Care Settings in Australia
Authors: Shephard Mark , Shephard Anne , Matthews Susan , Andrewartha Kelly
Published: October 2020

Context.—

Point-of-care (POC) testing has significant potential application in rural and remote Australian communities where access to laboratory-based pathology testing is often poor and the burden of chronic, acute, and infectious disease is high.

Objective.—

To explore the clinical, operational, cultural, and cost benefits of POC testing in the Australian rural and remote health sector and describe some of the current challenges and limitations of this technology.

Data Sources.—

Evidence-based research from established POC testing networks for chronic, acute, and infectious disease currently managed by the International Centre for Point-of-Care Testing at Flinders University are used to highlight the experience gained and the lessons learned from these networks and, where possible, describe innovative solutions to address the current barriers to the uptake of POC testing, which include governance, staff turnover, maintaining training and competency, connectivity, quality testing, sustainable funding mechanisms, and accreditation.

Conclusions.—

Point-of-care testing can provide practical and inventive opportunities to revolutionize the delivery of pathology services in rural and remote sectors where clinical need for this technology is greatest. However, many barriers to POC testing still exist in these settings, and the full potential of POC testing cannot be realized until these limitations are addressed and resolved.
Point-of-Care Testing Practices, Failure Modes, and Risk-Mitigation Strategies in Emergency Medical Services Programs in the Canadian Province of Alberta
Authors: Füzéry Anna K. , Kost Gerald J.
Published: October 2020

Context.—

Emergency medical services (EMS) programs have been using point-of-care testing (POCT) for more than 20 years. However, only a handful of reports have been published in all of that time on POCT practices in field settings.

Objective.—

To provide an overview of POCT practices and failure modes in 3 of Alberta's EMS programs, and to propose risk-mitigation strategies for reducing or eliminating these failure modes.

Design.—

Details about POCT practices, failure modes, and risk-mitigation strategies were gathered through (1) conversations with personnel, (2) in-person tours of EMS bases, (3) accompaniment of EMS personnel on missions, (4) internet searches for publicly available information, and (5) a review of laboratory documents.

Results.—

Practices were most standardized and robust in the community paramedicine program (single service provider, full laboratory oversight), and least standardized and robust in the air ambulance program (4 service providers, limited laboratory oversight). Common failure modes across all 3 programs included device inoperability due to cold weather, analytical validation procedures that failed to consider the unique challenges of EMS settings, and a lack of real-time electronic transmission of results into the health care record.

Conclusions.—

A provincial framework for POCT in EMS programs is desirable. Such a framework should include appropriate funding models, laboratory oversight of POCT, and relevant expertise on POCT in EMS settings. The framework should also incorporate specific guidance on quality standards that are needed to address the unique challenges of performing POCT in field settings.
Analysing meta-organizations with embedded brokering services performance modelled as a call-centre for supporting dynamic reconfigurability of networked and virtual organizations
Authors: Putnik Goran , Rodrigues Diana , Alves Cátia , Ávila Paulo , Castro Hélio , Cruz-Cunha Maria
Published: October 2020

Various companies choose to outsource the delivery of part of their services, so as not to deviate from its core business and improve the service level. This approach leads to a new type of organizations, so-called networked and virtual enterprises, where possibly a great number of companies work together without having direct contact but through a broker, as an intermediary, that streamlines the relationships between them. To enable high level efficiency, as well as some other functional requirements, the meta-organizations and brokering services are conceived as environments and services for networked and virtual enterprises operation and dynamic reconfigurations, representing a model of organizations-of-organizations, as an implementation of one of the Industry 4.0 models and ecosystem for networked and virtual enterprises dynamic reconfiguration. In this paper, the meta-organizations with embedded brokering services, modelled as call centres, are analyzed. Various simulations are presented, based on Erlang's formulas for some of design and performance measures parameters evaluation, such as service level, average waiting time, agent occupancy and service traffic intensity.
The effect of air injection system on airlift pump performance
Authors: Fayyadh Ekhlas , Mahdi Nibras , Mohammed Ali
Published: October 2020

In the current study, a novel design of an air injection system for an airlift pump was designed and tested. The pump has a circular cross-section and composed of three parts; suction pipe, injection system, and riser pipe. The riser pipe has a diameter of 31.7 mm and a length of 2 m. The performance of the pump was tested using different submergence ratios, ranging from 0.15 to 0.3, and the injected airflow rate was ranging from 1.65 kg/h to 13.32 kg/h. The results showed that both the airflow rate and the submergence ratio have a significant effect on the capacity and performance of the pump. Besides, it was found that the best range of pump efficiency was in the slug and slug-churn flow regimes. Moreover, the highest efficiency was at the most significant submergence ratio of 0.3. A reasonable enhancement in water flow rate was achieved using the current air injection design when compared with the conventional airlift pump injections system.
Erosion modeling in parallel gate valve
Authors: Ri Jong , Ripeanu Razvan-George , Dinita Alin
Published: October 2020

Gate valves, which are widely used in oil production and transportation processes, can be eroded by high fluid pressures and sand particles contained in crude oil during operation. This erosion can result in loss of valve thickness and shutdown of the operating system. Erosion is not uniform on valve elements, and it is different depending on the stages of opening the valve. In this paper, flow analysis and erosion rate analysis for the fluid flowing through the valve in different stages of opening were performed by using ANSYS Fluent 19.2. The gate valve model was designed by using AutoCAD, and the geometric dimensions and physical properties of the material required for modeling were determined according to the specifications of the gate valve installed in the oil pipeline. By the Reynolds calculation, it was disclosed that the fluid which flows in the valve has the characteristic of turbulent flow, and based on this calculation, the inlet length of the valve was determined. For the CFD analysis, the Euler method and the method of Lagrange were used. Using the k - e and DPM models according to the fluid characteristics of the turbulent flow, it was predicted the erosion rates of the surface generated by the sand which is the solid phase dispersed in the multiphase fluid. In addition, based on the von Mises method and the pressure distribution, data obtained by fluid analysis, the process of calculating the stress on the closing elements was presented. The fluid used in the analysis was petroleum with sand particles.
GIS-based multi-criteria wind farm site selection methodology
Authors: Rehman S. , Baseer M.A. , Alhems L.M.
Published: October 2020

It is prevalent that by 2050, the global energy demand would increase by 50% to the current demand. The projected demand for electricity in Saudi Arabia is expected to exceed 120 GW/year by 2032. The Saudi government has set a goal of generating 9.5 GW of wind energy by 2023. In this study, firstly, a spatial interpolation technique is used to build a first accurate wind map of the entire country, then a GIS-based multicriteria decision-making model is developed to select suitable wind farm sites considering various ecological, environmental and socio-economic criteria. All the identified criteria are given equal weightage in the model. Therefore, with noncompliance with even a single criterion, the associated complete area is considered unsuitable. As a case study, this model is independently applied to four regions covering the entire of Saudi Arabia. In the northern region, three wind farm sites are identified. The central area has a more suitable area compared to other regions mainly due to good wind resources and road and grid connectivity. The suitable sites in the Eastern region are located between Dammam and Hafr AlBatin city. The southern region has a scarcest suitable area for wind power exploitation located near the province of Madinah.
New reliability-based model of stock optimisation for railroad passenger wagon maintenance
Authors: Milković Vili , Lisjak Dragutin , Kolar Davor
Published: October 2020

Today's railroad passenger wagons experience a large frequency of failures due to a large number of usage hours, and consequently planning maintenance is complex and expensive. Due to high maintenance costs, special attention should be given to the planning of part storage. This study develops a model which by using the data collected in the maintenance process, serves in optimising the costs of stock parts for a set level of reliability. The data on drive schedules and wagon repairs, mean time between failures and maintenance costs were collected over a year by a rail carrier for its entire rolling stock of passenger wagons. The first phase of developing the model using regression methods provided mathematical models of reliability dependency in terms of train use time and costs of spare parts for groups of passenger wagons grouped into technical characteristics. In the second phase, the problem of optimal stocks was solved by applying linear programming methods. The newly obtained model can be applied in practice as a tool for optimising the required stocks of parts based on a set level of equipment reliability and set maintenance costs.
Development of automated liquid filling system based on the interactive design approach
Authors: Abdullah Oday , Abbood Wisam , Hussein Hiba
Published: October 2020

The automatic liquid filling system is used in different applications such as production of detergents, liquid soaps, fruit juices, milk products, bottled water, etc. The automatic bottle filling system is highly expensive. Where, the common filling systems required to complex changes in hardware and software in order to modify volume of liquid. There are many important variables in the filling process such as volume of liquid, the filling time, etc. This paper presents a new approach to develop an automatic liquid filling system. The new proposed system consists of a conveyor subsystem, filling stations, and camera to detect the level of the liquid at any instant during the filling process. The camera can detect accurately the level of liquid based on the imaging process technique (Edge Detection Approach). In order to achieve the aim of this work, Arduino board is used as the controller unit in the automatic operation of developed filling system. The developed automatic liquid filling system is designed to be not expensive compared to the other available filling systems on the markets. The system is also easy to operate and user-friendly,where only simple steps are required to operate the filling system or modify the working condition.It was found, based on results, that the Prewitt edge detection is the optimal method that should be applied to obtain high accuracy of results and quick response of developed system.
Improvement of upsetting process of four-beam workpieces based on computerized and physical modeling
Authors: Markov Oleg , Kukhar Volodymyr , Zlygoriev Vitalii , Shapoval Alexander , Khvashchynskyi Anton , Zhytnikov Roman
Published: October 2020

The method of upsetting of large ingots has been investigated in this work. The proposed method consists in upsetting of profiled workpieces with concave faces. An angle of the concave faces was 150°. A relative depth of the concave faces has been varied in range 15%…25% from workpiece's diameter. Strains effective and mean stresses in the longitudinal cross-section of the workpiece with concave faces after upsetting have been determined by FEM. A value of compressive stresses has been determined based on a parameter of the stress state. FEM allowed to find what a rational depth of the concave faces should be, which has to be 15 % from workpiece's diameter. Maximum closing of the internal defect take place for this depth of the concave faces. Results of the FEM have been tested by experimental investigations. It has been established that upsetting of the four-beam workpieces improved a quality of the massive parts.
An experimental test of the effect of cup diameter on the power performance of novel design HC-type VAWT
Authors: Alfian Mizar , Puspitasari Poppy , Taufiq Ahmad , Trifiananto Muhammad , Aripriharta A
Published: October 2020

Wind energy is one solution to overcome the energy problem in Indonesia. This study aimed to analyze the effect of cup diameter on the power performance of an HC-type vertical axis wind turbine (VAWT). The wind turbine used a combination of an H-type Darrieus wind turbine and a type-C rotor VAWT. The Darrieus HC-rotor wind turbine blade has a height H = 800 mm and diameter D = 800 mm with C-rotor variations on the tip with diameters of 76,2, 101,6, and 152,4 mm. The wind tunnel used an electric motor with a power of 1 HP (740 Watt) and 1400 rpm connected to a fan. The variation of wind speed was set to 2, 3, 4, 5, 6 and 7 m/s. The results showed that: (a) the highest rotation speedal speed was achieved by the HC-rotor diameter of 76,2 on 105 rpm with a wind speed of 7 m/s; (b) the highest value of the coefficient of power (Cp) is achieved by the HC-rotor diameter of 101,6mm (c) the highest value of the coefficient of torque (Ct) is achieved with the HC-rotor diameter of 152,4mm (d) the Darrieus HC-rotor wind turbine is suitable to be used in tropical regions that have low wind speeds. This result provides important information about the effect of the C rotor radius on the performance of HC-rotor Darrieus wind turbine blade vertical axis.
Analysis of influencing factors that can cause errors in the application of modern methods of sliding bearing diagnostics in machine and electrical systems
Authors: Žegarac Nikola
Published: October 2020

Introduction/purpose: The paper presents the application of modern methods in the diagnostics of sliding bearings and the analysis of influencing factors that can cause errors in such an application. Possibilities to determine with certainty when and where problems affect sliding bearings during system operation are presented. It is also shown how the system will continue to function over time. Causes of failures and the manner of their elimination are predicted, as well as the time for planned maintenance of technical systems. Method: The new method solves the problem of sliding bearing diagnostics by measuring the dynamic trajectories of the sleeve in the sliding bearing and by measuring vibration parameters on the inner and outer surfaces of the technical system. The dynamic trajectories of the bearing sleeve are measured with non-contact probes; therefore, the centering of probes in relation to the geometric center of the bearing is very important. Vibration parameters, directly related to the clearance in the sliding bearing, are measured on the inner and outer surfaces of the system. The choice of vibration parameters and measuring points is very important. This method has a number of advantages over other diagnostic methods, as it is easy to access measuring points. Results: By measuring the dynamic trajectory of the sleeves in the plain bearing and vibration parameters on the inner and outer surfaces, the bearing clearance quantities are determined, including: normal condition, initial clearance size, its further increase, bearing clearance sizes, and the moment when the condition parameters are close to the upper limit of the permissible bearing clearance. Conclusion: New diagnostic methods and monitoring systems can be widely applied to: internal combustion engines, all piston machines, hydroelectric power plants, thermal power plants, processing plants, and many other systems.
Småstater og cybervåben – nye muligheder og nye begrænsninger
Authors: Jensen Mikkel Storm
Published: October 2020

Denne artikel handler om, hvordan cybervåben giver småstater en række nye strategiske muligheder. Den forklarer først, hvorfor der ikke er megen hjælp at hente i den eksisterende forskningslitteratur. Artiklen gennemgår derefter en række generelle karakteristika for cybervåben ét ad gangen og beskrive hvad de betyder for småstater generelt og Danmark specifikt. Det konkluderes, at cybervåben delvist ændrer balancen mellem småstater og stormagter i småstaternes favør. Men der er grænser for de muligheder, våbnene åbner. Særligt for småstater, der som Danmark knytter deres sikkerhedspolitik snævert til medlemskab af en militær alliance som NATO. Cybervåben er vanskeligere at anvende i NATO end konventionelle våben både på det strategiske og operative niveau – og især hvis vi ikke er i krig. Det er derfor måske ikke overraskende, at det stadig ikke er helt klart, hvordan Danmark vil anvende disse våben – særligt i fredstid.
Moderne tider. Aktiv krisestyring – er Keynes tilbage?
Authors: Olesen Finn
Published: October 2020

På sin vis har forskningen i Keynes’ forfatterskab vist sig at være særdeles sejlivet. Således dannede dette baggrunden for den keynesianske æra og gav nogen inspiration til den ny-keynesianske teoridannelse. Der forskes også stadigvæk aktivt i forfatterskabet især inden for post keynesianske kredse. Om end i perioder under pres forsvandt keynesianismen dog aldrig helt, og efter The Great Recession og Covid-19-pandemien er keynesianismen så aktivt tilbage i makroteorien? Og hvad med den post keynesianske tænkning? Vinder denne også øget anerkendelse? Om især disse aspekter handler nærværende artikel.
Mere moralisering end analyse i et biased kampskrift for DR
Authors: Larsen Bøje
Published: October 2020

Denne artikel analyserer en bog om Danmarks Radio skrevet af Christian S. Nissen, tidligere generaldirektør for DR. Han argumenterer for, at danske politikere i deres styring af DR ikke har magtet at modvirke truslerne fra internationale medier som YouTube og Netflix, som ifølge ham vinder frem med unfair metoder. Dette mener han vil svække dansk sammenhold og kultur. I artiklen her argumenteres for, at hans bog er et biased partsindlæg for det gamle DR, som ikke selv har formået at komme ind i en ny medieverden. Selvom Nissen præsenterer sig som tidligere forsker og henviser til forskning, er hans brug heraf overfladisk eller forkert.
La migration numérique d’une oeuvre pionnière avec live electronics.
Mesa (1966) de Gordon Mumma
Authors: Goldman Jonathan , Lecavalier Francis , Pelz Ofer
Published: October 2020

Cet article résume les retombées d’un projet de reconstruction d’une oeuvre
pionnière de live electronics, à savoir Mesa (1966) du compositeur
étatsunien Gordon Mumma (né en 1935). Une reconstruction de cette oeuvre a été présentée
dans le cadre du festival Montréal/Nouvelles Musiques le 27 février 2017 par l’auteur et les
collaborateurs de cet article : Jonathan Goldman au bandonéon, Francis Lecavalier à la
conception informatique, et Ofer Pelz à l’interprétation de la partie électronique. Au cours
de cette « migration », l’oeuvre, fondamentalement analogique, a été reconçue pour un
équipement numérique contemporain avec le consentement du compositeur. S’inscrivant
nettement dans la lignée de l’École de New York cageienne, Mesa revêt un statut
ontologique curieux : elle est le produit d’une indétermination passablement radicale. Comme
c’est le cas pour l’oeuvre de Cage, Mesa et sa reconstruction numérique nous force
à repenser l’ontologie et l’épistémologie de l’oeuvre musicale.
Musicologie pratique à l’ère des réseaux sociaux. Le cas des notes de programme numériques de l’osm au sein du paysage musical francophone
Authors: Bernard Justin
Published: October 2020

Depuis leur émergence au milieu duxixe siècle, les notes de programme n’ont eu de cesse de s’adresser au public de concerts. Les besoins sont multiples, voire même divergents : donner des outils de compréhension intelligibles aux novices et en même temps susciter la curiosité d’auditeurs déjà initiés. À l’ère d’Internet et des réseaux sociaux, ces outils de médiation, qui relèvent de ce que l’on pourrait appeler une musicologie « pratique », sont plus que jamais en évolution. Ils offrent de réelles avancées en termes de contenu audio et vidéo, mais suscitent, par ailleurs, des interrogations quant au rôle que les orchestres symphoniques, notamment, veulent bien leur faire jouer. Dans cet article, nous tenterons de répondre à cette nouvelle réalité à travers une multitude d’exemples concrets de médiation, dont certains ont été réalisés dans le cadre d’un projet que nous avons mené en partenariat avec l’Orchestre symphonique de Montréal.
Economics in the Age of COVID-19
Authors: Gans Joshua
Published: October 2020

A guide to the pandemic economy: essential reading about the long-term implications of our current crisis.

The COVID-19 pandemic has unleashed a firehose of information (much of it wrong) and an avalanche of opinions (many of them ill-founded). Most of us are so distracted by the everyday awfulness that we don't see the broader issues in play. In this book, economist Joshua Gans steps back from the short-term chaos to take a clear and systematic look at how economic choices are being made in response to COVID-19. He shows that containing the virus and pausing the economy—without letting businesses fail and people lose their jobs—are the necessary first steps.

Gans outlines the phases of the pandemic economy, from containment to reset to recovery and enhancement. Warning against thinking in terms of a “tradeoff” between public health and economic health, Gans explains that containment gives us the opportunity to develop effective testing that will make it safe for people to interact. Once the virus is contained, we will need to pivot toward innovating, and, finally, we will come together to plan how to protect ourselves from future pandemics. He looks at policy tools that might aid an economic recovery, distinguishing between economic losses during a pandemic and a recession.

Gans lays out the economic choices accessibly but with urgency, leaving politics out of it. Economics in the Age of COVID-19 is essential reading for anyone interested in the long-term implications of our current crisis.

An open access version of Economics in the Age of COVID-19 for community commentary is available at https://economics-in-the-age-of-covid-19.pubpub.org/