Underlay Versus Modified Circumferential Subannular Graft Technique in Endoscopic Tympanoplasty

Background and Objectives To describe and evaluate modified circumferential subannular tympanoplasty (MCST) via endoscopic approach, we compared the results of MCST to those of the underlay technique and the results of previous studies.Subjects and Method A retrospective comparative study was conducted of 31 patients who underwent endoscopic transcanal tympanoplasty. Patients were classified into the MCST group (n=11) and the underlay group (n=20) according to the graft technique. Demographic data, size and location of the perforation, pre- and postoperative hearing, operating time, complication rate, and graft success rate were analyzed in each group.Results No significant differences between the two groups were observed in the demographic data or the locations of the perforations. The sizes of the perforations were 31.4±14.3% and 25.0±18.1%, respectively. The average operating times were 68.6±16.5 min and 64.9±9.3 min, respectively, and canaloplasty was not required in any patient. The postoperative hearing improvement and air-bone gap were not significantly different. No postoperative complications were observed in either group.Conclusion MCST is a feasible and effective technique for endoscopic transcanal tympanoplasty. The postoperative results and operating times of MCST were comparable to those of other graft techniques. MCST showed more stable results in anterior perforation than in underlay graft.

Assessment of the intensity of engine oil contamination during operation

The acceleration of internal combustion engines leads to an increase in thermal and mechanical loads on the most critical parts. To ensure the required resource indicators in conditions of increased loads, it is necessary to use high-quality lubricants, the requirements for the operational properties of which are also steadily increasing. In order to ensure the necessary physical and chemical characteristics of engine oils, additives are introduced into their composition, but during operation the quality of engine oil decreases, the reasons for this are both the destruction of additives, and the accumulation of dirt particles in the oil and the ingress of fuel and coolant into the oil. The conducted studies are devoted to determining the intensity of engine oil contamination under operating conditions in the Wärtsilä 6L20 engine lubrication system and the effectiveness of the dispersing additives contained in the oil. Samples of Petro Canada and TARO oils brands were used as prototypes at the beginning of the operational period, at the time of average operating time and at the time of oil change. The dispersing ability of the oil was determined by the method of assessing the oil stain. According to the results of the research, it is concluded that when the properties of the oil change as a result of contamination, their dispersing ability remains satisfactory. This result can serve as a justification for extending the service life of engine oil, provided that its properties are monitored during operation.

Estimating the Potential of Electric Vehicles for Travelling to Work and Education in Melbourne, Victoria

This paper aims to estimate the potential of electric vehicles (EVs) in Melbourne, Victoria, using the Victorian Integrated Survey of Travel and Activity (VISTA) data. The investigation of whether EVs with different all-electric ranges (AERs) can replace car travel to work and education is the focus of this paper. The results showed that EVs would be able to replace most car travel to work (68.5% to 97.1%) and car travel to education (71.9% to 96.9%), with AERs increasing from 40 km to 100 km, assuming car drivers are willing to use an EV. It is estimated that the average operating cost savings per person would be up to AUD 3.12 and AUD 2.79 each day, regarding travel to work and education, respectively. Considering both travel to work and education, EVs could replace up to 33.8 million kilometres of car travel, consuming around 7.6 GWh and resulting in a reduction in carbon dioxide (CO2) emissions of about 610 tons each day.

Instantaneous speed as a tool for defining accessibility in the road network of Ocaña, Colombia

The application of the concept of instantaneous speed to the movement of vehicles on a city’s road network made it possible to establish average operating speeds. With the help of software based on geographic information systems, it was possible to determine the minimum travel times required by vehicles to move between two points on the network. Through the above analysis of speeds and travel times, applied to the road network of the municipality Ocaña, Colombia, it was possible to establish the time required by various types of vehicles to travel between the different points of the road network, allowing to define the level of accessibility to move between different areas of the city. The analysis required the updating, characterization, georeferencing and determination of the instantaneous speeds for each trip in the different arcs of the network and the subsequent determination of the average travel time curves in the network. The urban area of the city is covered with an average travel time of 15 minutes and the operating speeds are between 5 km/h and 31 km/h, with variations depending on the type of vehicle (bus, taxi, motorcycle).

Positive Influence of Certification on the Financial Performance of Cocoa Production Models in Cameroon

Cameroon plans to double its cocoa production in the coming decade in line with international requirements for sustainable and deforestation-free cocoa. Private certification, which has developed considerably in recent years, should help achieve this objective. Based on a literature review and 63 individual interviews with farmers, we identified four archetypes of cocoa production using the criteria of plantation size, degree of shade, and support from public or private extension services. We analyzed the average operating accounts of the four archetypes. Our findings show that the net profit rates obtained by small-scale certified producers are 14% (in the savannah zone) and 24% (in the forest zone). These rates are much higher than for the other two production models. Certification schemes provide technical and financial support, which has a positive influence on the practices of many small-scale producers and compensates for the lack of public services, which are now almost non-existent. A hybrid governance of the cocoa sector in Cameroon could clarify and improve the organization of the interactions between public regulation and private certification systems.

One-stage thoracoscopic resection of bilateral bronchiectasis

Objective To evaluate the results of one-stage thoracoscopic resection of bilateral bronchiectasis. Methods Between June 2009 and December 2020, there were 23 patients selected for one-stage thoracoscopic resection of bilateral bronchiectasis. Their average age was 58.5 (36–73). Female patients were more common, accounting for 17 (74%). Preoperatively, 17 (74%) patients mainly presented with hemoptysis and the other 6 (26%) patients with purulent sputum. Results In these 23 patients, a total of 121 segments were resected, with an average of 5.26 segments, ranging from 3 to 9 segments. Five of 17 patients with massive hemoptysis underwent ligation of bronchial arteries in addition to lung resections. The average operating time was 271 min, ranging from 145 to 500 min. The average blood loss was 108 ml, ranging from 20 to 600 ml. The average postoperative hospital stay was 8 days, ranging from 3 to 20 days. There was no surgical morbidity or surgical death. Hemoptysis and purulent sputum of all patients was almost controlled after surgery. Conclusion One-stage thoracoscopic resections of bilateral localized bronchiectasis could be well-tolerated and safe for these selected patients. The one-stage operation could shorten the course of treatment.

Comparative Analysis of the Environmental Performance of Delivery Routes in the City Center and Peri-Urban Area of Madrid

Cities are experiencing a process of suburbanization and last-mile delivery has grown, worsening traffic congestion, pollutant emissions, and citizens’ quality of life. Based on a real-life case study, this research compares the environmental performance of different delivery routes carried out by Diesel Light-Duty Vehicles (LDV) according to delivery area, city center or peri-urban. Some 242 delivery routes performed by thirteen drivers were recorded for one month, including instantaneous GPS position, speed, and other parameters (7262 km travelled). Four different delivery routes typologies were compared, and the drag function of the vehicles was characterized. It enabled calibration and modelling dynamics to calculate fuel consumption and pollutant emissions according to delivery routes. The results show that pedestrian crossings, traffic lights, and traffic congestion reduce the average operating speed by up to 57% in the city center and consequently overall energy efficiency. Our results highlight the urgency of replacing diesel LDV for deliveries in the city center with no-motorized transport modes and of implementing intermodality to cover deliveries in residential peri-urban areas. Due to low speeds and frequent start-stops, the efficiency of vehicles in these areas is reduced to a minimum and pollutant emissions increase. The outputs set a basis for recommendations for using LDV only for delivery routes with less traffic interruptions and foster intermodal solutions.

Indicator for Assessing Availability of Rolling Stock for Public Urban Passenger Transport

The objective of the article is to develop and to substantiate adequacy of the proposed indicator for assessing availability of rolling stock for urban mass transit or urban passenger transport (UPT). As such an indicator, it is recommended to use a calculated indicator: a conventional one-hundred-seat vehicle. The currently used indicators characterising provision of UPT with vehicles, consider only the physical number of the latter. This does not provide an assessment of carrying capacity of UPT, considering the existing operating conditions (real operating speeds on the routes of UPT, the existing level of the coefficient of the fleet being used on the routes as compared to the total number of fleet units, etc.). The proposed indicator of availability of the rolling stock considers not only the natural number of vehicles, but also their passenger capacity, the indicated significant technical and operational indicators of the vehicle fleet. The basis for assessing the carrying capacity of the rolling stock fleet is a conventional one-hundred-seat bus, which performs transportation on routes with an average operating speed. For real buses, this basic unit is adjusted in accordance with real travel speeds and the prevailing values of technical and operational indicators. A similar adjustment is performed for real trolleybuses and tram cars, which makes it possible to level the operational differences in the rolling stock of various types of UPT to compare them in terms of carrying capacity.The methodology used in preparation of the article is based on the integrated use of scientific knowledge in the fields of applied science on operation of transport, statistics (statistical observation and accounting of the work of UPT), a comparative analysis of indicators used in various industries, in particular, in agriculture to assess the level of provision with the main production vehicles (conventional tractor), benchmarking research and development of Russian and foreign authors on the problem of improving operation of UPT.The indicator is intended for use in development and assessment of the level of implementation of programs for development of UPT and the urban environment, analysis of the quality of transport planning and services provided to passengers, comparisons of provision with vehicles in different cities.

Analysis of the types of agricultural sprayers’ nozzles

The article provides an analysis of modern types of sprayer sprayers, as well as the most popular and versatile type of sprayers suitable for most different types of agricultural crops. The characteristics of the volumetric flow rate of the working fluid by sprayers according to the world standard - ISO 10625 are reflected. Recommendations are given for installing the sprayer rod, depending on the angle of spray and the frequency of installation of sprayers. Various materials for the manufacture of sprayers and their average operating life expressed in thousand hectares are analyzed. The results of the study show a comparison of the two main types of sprayers – slot and injection, used for most herbicides, systemic phengicides, pesticides, insecticides, etc. The conclusions provide recommendations on the optimal choice of the type of sprayer for applying chemical plant protection products and for applying liquid mineral fertilizers.

The Relationship between Extent of Internationalization and Firm Performance (Taiwan 1992–2017)

The purpose of this study was to discuss the impact of the extent of internationalization on firm performance measured for firms with a high Tobin’s Q (firms with good operating performance), a median Tobin’s Q (firms with average operating performance), and a low Tobin’s Q (firms with poor operating performance). In addition to discussion on the impact of internationalization on firm performance, this study also discussed the impact of corporate proprietary assets (using assets, R&D, marketing, and management-related variables as moderating variables) and control variables (scale of company, debt-asset ratio, firm age, board structure, and proportion of pledged shares by directors) on firm performance. The research results showed that there is an S-shaped relationship between extent of internationalization and firm performance. However, further discussion found that there is an S-shaped relationship between extent of internationalization and performance for firms with a high Tobin’s Q but a slight decline in the middle of the S-shaped curve, as well as a general linear negative correlation between extent of internationalization and performance for firms with a median Tobin’s Q and an inverted U-shaped correlation between extent of internationalization and performance for firms with a low Tobin’s Q.