bluuebunny/crossref_metadata_2025 huggingface dataset:
Using linear regression with the least squares method to determine the parameters of the Solow model
Authors: Boyko A A , Kukartsev V V , Tynchenko V S , Korpacheva L N , Dzhioeva N N , Rozhkova A V , Aponasenko S V
Published: July 2020

The article shows that a simple method for calculating the values of the coefficients at which the production functions of Cobb-Douglas and Robert Solow best approximate statistical data, as well as determining the accuracy of the model and coefficients, is linear regression using the least squares method. By means of a regression analysis, the parameters of the effect of the introduction of innovative processes and the coefficients of the level of technology, labor elasticity and capital of production functions are determined. The initial statistics for the calculations were taken on the website of the Federal State Statistics Service in the relevant sections. Using the constructed functions, the influence of such factors as labor, capital, innovative processes on the long-term change in the volume of production in Russia was estimated, and the nature of the return on these production factors was determined. It is shown that the considered production functions in relation to real data demonstrate an increasing return on labor and capital. To determine the reliability of the approximation, a linear correlation coefficient (Pearson correlation coefficient) was calculated. As a result of calculations with the formula, the value of the Pearson coefficient r

xy
= 0.9844 was obtained. From the obtained value, it was concluded that there is a strong correlation between the variables, the variables correlate positively and the reliability of the approximation is high.
Investigation of the effect of various silicon contents on the crystallization pattern and the composition of silumin phases
Authors: Cherepanov A I , Kukartsev V A , Tynchenko V S , Korpacheva L N , Makarchuk I Yu , Dremin R S
Published: July 2020

Silumin is an alloy composed of aluminum and silicon, that can contain up to 22% of silicon. It has a low cost, wear resistance and low relative weight. The main industries for using silumin are aircraft manufacturing and mechanical engineering. Given the relatively low cost of the alloy, silumin is used to produce cheap household appliances, which are often not inferior in reliability to expensive analogues. Recently, silumin has gained particular popularity in the arms industry, especially for the production of air rifles. The properties of these alloys primarily depend on the Si content, which leads to changes in its microstructure. The paper presents studies of the effect of silicon content on changes in the nature of crystallization and phase composition of silumins with Si content from 1 to 21%.
Classical system approach to reverse engineering
Authors: Ivonov A V , Volkova E V , Daudov I M
Published: July 2020

The paper presents one of the possible solutions of the reverse engineering problem from the point of view of the classical system approach, as well as highlights the direction for the development of a complex software product. This approach will make it possible to change the modern practice of reverse engineering, which is applied everywhere. This practice requires expert evaluation by operator teams on non-acceptance basis. The approach proposed by the authors will significantly minimize human participation in this process.
Influence of mechanical and plasma shockwaves on the structure and properties of superconductors
Authors: Mihailov B P , Alibekov S Ya , Krutskih N A , Egorov A V , Pavlov A I , Lysyannikov A V , Kaizer Yu F , Kuznetsov A V
Published: July 2020

The article presents the results of studying the critical temperature, critical current, and field dependencies of superconducting Bi-2223 and MgB2 multilayer tapes after them being subjected to the influence of shock waves generated at the Plasma Focus test bench and mechanical impacts of various intensities. The influence of the specific energy, the number of impacts, the distance of the samples from the plasma anode, the energy of the falling shock mechanism, and the step of moving the impacts was studied. Studies have shown that the critical current Jc can be increased by 50 % in magnetic fields of 2–3 T. In this case, the grains are crushed, compacted, homogenized, and the impurity content changes. The results of microanalysis of superconducting interlayers in the initial state and after influence of shock-wave of plasma show an improvement in the homogeneity of the distribution of the main components (Mg and B) and impurities (C and O).
Increasing service life and reliability of centrifugal separators by applying new materials
Authors: Khabibullin M Ya
Published: July 2020

This paper analyzes stress-strain behavior and bearing capacity of a rotor in a self-discharging separator, diameter 500 mm, manufactured from parts that underwent a hardening cycle. Three variants of the rotor were studied having the same design but differing in body materials: austenitic steels 06X17H13M3-BД, ALIII-23-43-02 and austenitic-ferritic steel 10X26H5M, ALIII-23-24. Research results allow recommending austenitic-ferritic steel for manufacture of separator rotors, as they provide necessary margin of safety for the design.
Analysis of equipment utilization at random order arrivals and random output
Authors: Korolkova L I , Mashrabov N , Herreinstein A V , Herreinstein E A
Published: July 2020

The aim of this work is to study equipment utilization of an enterprise. To examine the random order arrivals and random output, we use the supply and demand model, in which demand is equipment utilization and supply is product output. There are no restrictions on the type of value, deterministic or random, and on the form of the distribution function of demand and/or supply. The initial data are integer random supply and demand with arbitrary distribution functions. The output parameters of the model are supported and unsupported demand, and unused supply. These parameters are also integer random variables for which the model allows obtaining their functional characteristics. We show that the conventional deterministic approach to calculating the quantity of equipment as a ratio of the average product demand to the average machine capacity leads to both equipment downtime and consumer unsupported demand. We solve this problem for the enterprise manufacturing temperature sensors. When two pieces of equipment are used to produce a certain type of sensors under study, the average unsupported demand is about 12% of the average monthly order and varies from 17 to 112 (non-produced) sensors. Only five months a year the order is fully executed within a month; the equipment is fully utilized for 7–8 months a year. The model allows calculating not only the average values of parameters, but also their distribution functions.
Metering the flow of oil with drag-reducing agents
Authors: Krasnov A N , Prakhova M Yu
Published: July 2020

The bulk of oil and petroleum products is carried by oil and petroleum trunklines. The performance of such transport depends on many factors, including the process parameters (the pipeline diameter, the number of booster stations, and the power of trunkline pumps) and the parameters of the carried medium itself, mainly its viscosity. Most energy it spent to overcome the loss of pressure due to the friction between the fluid layers. These losses increase with the turbulence of the flow. Turbulence can be reduced by drag-reducing agents (DRA) that level off the flow of the fluid. However, this might jeopardize the calibration of the turbine and ultrasonic flow meters. This paper presents experimental research into such flow meters used for metering the flow of oil with and without DRA. The findings suggest that when using a DRA, the flow meters should be calibrated with the DRA, in which case the measurement error will be within the standard-required 0.15%.
Simulation-dynamic model of working time costs calculation for performance of operations on CNC machines
Authors: Kukartsev V V , Boyko A A , Mikhalev A S , Tynchenko V S , Rukosueva A A , Korpacheva L N
Published: July 2020

This article presents a simulation-dynamic model for determining the time spent on machining operations on machines with a numerical control (CNC). The model is developed on the basis of the system dynamics method using Powersim Studio tools. In the shown model, the calculations of the probabilistic deviation of the actual time of technological operations on CNC machines from the technically sound time norm were carried out on the basis of the Gaussian normal distribution law. The model was used as a tool to study the probabilistic distribution of time for equipment retooling and to perform technological operations on HAAS SL-20 CNC machines. The study allows us to conclude that the constructed simulation dynamic model is quite universal and, on its basis, it is possible to carry out a variety of studies concerning various aspects of the technical substantiation of the time norms for performing machining operations on CNC machines.
Methods for monitoring the technical condition of plate heat exchangers
Authors: Mukhametzyanov Z R , Kulakov P A , Rubtsov A V
Published: July 2020

The article sets the task of developing a method for reducing the complexity of repair of plate heat exchangers by optimizing the method of monitoring the technical condition of equipment. To solve this problem, it is proposed to develop a methodology for determining the optimal location of thermoelectric modules. The article presents an algorithm for solving the problem of choosing the location of thermoelectric modules. The developed method allows to evaluate the condition of the plates for deposits, their thickness in real time and on working plate heat-exchange equipment. The data obtained may be used to decide on repair and restoration operations.
Error-control algorithm of voice messages transmission
Authors: Lukyanova E A , Zhigalov K , Salgiriev A , Soltamuradov M
Published: July 2020

High-speed and high-quality communications are required to ensure a smooth process of timely receipt and processing of information. The speed of obtaining information depends on the speed of response and timely management decisions. The development of information and telecommunication technologies has led to an increasing integration of communication and voice messaging systems implementing information processes in the control system. In communication systems where it is important to ensure the integrity, availability and confidentiality of transmitted information when low-bandwidth communication channels are used, voice information is encoded by special compression algorithms. Prefix codes are common in various fields of information technology. Many information compression algorithms are based on them, and they are used by different protocols. The use of run-length coding will reduce the speed of a transmitted signal and increase the throughput.
Theoretical aspects of prototyping
Authors: Orobey M N , Alchinov A , Daudov I M
Published: July 2020

The evolution of programming began at a time when most programs were developed by a single developer. As the complexity of the programs increased, the complexity of their development, debugging and the number of participants in the process also increased, which led to the development of automation systems for programming and organization of teamwork, and later to the development of tools and methods for software design (CASE-tools).
Limit length of long Ethernet telecommunication lines for industrial information systems with centralized structure
Authors: Semenov A B
Published: July 2020

Possibilities of application of Fast Ethernet repeaters for extension of the limit length of twisted pair channel of industrial automation systems are considered. A mathematical model of the line with 100 Mb/s performance has been introduced, which allows to perform engineering calculation of the limit length of a single segment and the whole line. It is shown that in the case of Class 1 devices in terms of power consumption in the line, up to three repeaters can be used, one of which is used in the booster mode and must support the PoE+ mode. It has been established that for Class 1 devices, the main means of extending the limit length of the channel is using a twisted pair cable of Category 5e with cores of increased diameter (0.55 mm and more).
Non-destructive testing as an element of monitoring the operational reliability of rice systems for the rational use of water resources
Authors: Solodunov A A , Bandurin M A
Published: July 2020

This article presents the results of monitoring the operational reliability of structures of an on-farm network of rice systems for the rational use of water resources. At present, the state of the water basin of the Kuban River is characterized by a high level of economic and integrated development. The amount of irretrievable withdrawal of water resources in the Lower Kuban exceeds the maximum permissible withdrawal limit by 3.5 times. Thus, the Kuban River has virtually no free water resources in the lower reaches after the Krasnodar reservoir, for further development. Studies conducted on the on-farm network facilities have shown that closed structures on rice systems are in a worse position than open ones. The drainage structure in the form of a pipe was examined in detail, since the structure is exposed and accessible for inspection and measurements. However, part of the structure that was under water during operation got serious damage; the pipeline was destroyed along the entire length from the junction to the water intake well. The use of monitoring the operational reliability of the structures of rice systems has shown the opportunity to improve the quality of the control effects of technical operation, reduce repair costs and obtain the expected economic effect, and also allows to solve the technical problems of long-term operation, classification and determination of damage volumes of the examined structures to improve the calculation of the residual reserve of capacity and establishment the duration of their continued functioning. The use of non-destructive testing methods allows you to scientifically substantiate the costs of maintenance and overhaul, to clarify the rules for operating on-farm network facilities.
Influence of medium composition on biomineralization and morphology of newgrowths
Authors: Strokova V V , Duhanina U N , Balitsky D A
Published: July 2020

The research presents rational (from the point of view of processability) types of bacteria, nutrient media, biochemical agents and their quantities for biogenic mineral formation under specified conditions. The principles of the influence of metabolism processes of microorganisms on the change in the alkalinity of medium are established. The dependences of morphological parameters (size, shape) of mineral components formed during biomineralization in simulated media on the type of nutrient in the crystallization medium are established. The authors formed a phenomenological model of the processes occurring as a result of the bacterial activity of various strains, nutrient components and precursors of crystallization initiation as stages of structure formation during the production of building materials.
Creation of optimal cross-country route using GIS
Authors: Zhigalov K , Gavrilova Zh L , Daudov I M
Published: July 2020

Nowadays the systems for routing are well distributed. However, they all involve routing along existing roads. The article considers the options for the construction of transport routes over cross country, taking into account the technical characteristics of vehicles. The information in this article can be used to solve the problem of the creation of the software designed to develop an optimal route for the movement of technical equipment, taking into account a wide range of features of movement on the ground. In addition, the article discusses possible options for the improvement of modern navigation systems.
Fisheries technology innovation supports the Citarum Harum program
Authors: Haryadi J , Nastiti A S , Krismono
Published: July 2020

Indonesian waters cover about 75% of Indonesian areas and have an abundance of fish resources that must be used carefully and responsibly to maintain its sustainability. Indonesian waters must be considered by authorities and communities to increase fisheries production and habitat quality. One way is by using technological innovation. The Government launched the Citarum Harum Program, as the Government’s attention to the Citarum River. Citarum River has about 11,323 km2 large. The length of the river is about 300 km, starts from Mount Wayang until Java sea. Citarum River dammed into three reservoirs developed for fish culture (Saguling Cirata and Juanda) and industries, domestic, agriculture also animal husbandry along the river. The impact of the river is experiencing pollution. The World Bank responded to this condition and has the intention to improve the water quality of the Citarum river. The Research Institute for Fisheries Resources Enhancement under The Ministry of Marine and Fisheries made efforts to control industrial waste pollution through technologies. The technologies are phytoremediation, culture-based fisheries models (blooming Cyanophyceae, and Eichhornia crassipes with herbivorous/planktivorous fish stock), and KJA Smart. Innovation in fisheries technology is one of the bases for the management of water bodies in support of the Citarum Harum program.
Suitability water quality parameters for seaweed culture at Muara Gembong coastal area, Bekasi District
Authors: Mujiyanto  , Syam A R , Wijaya D , Purnamaningtyas S E
Published: July 2020

Seaweed is one of the vital export aquaculture commodities in West Java of Indonesia. Since 2013, seaweed production in Muara Gembong Sub-District, especially Pantai Mekar Beach and Pantai Sederhana Villages, can be produced 7.000 tons from total 10.000 seaweed culture fisheries of Bekasi District (80%) that was developed with a polyculture system. To ensure the long-term success of providing seaweed production, evaluation of suitable location is an essential step in any aquaculture operation. This study was conducted to analyze suitable sites for seaweed aquaculture in the coastal area of Muara Gembong based on the condition of water quality. Water quality data were collected from 11 stations during field surveys in March, July, and October 2018. Water quality parameters were observed with physical parameters (Secchi disk transparency, temperature, and depth) and chemical parameters (salinity, pH, DO, phosphate, and nitrate). Evaluation of water quality data included compile of matrix suitability design through some works of literature. The suitability coastal areas were analyzed to get suitable location used GIS software from coordinate data and water quality parameters, which were compared. The class “suitable” has a score of 4, the “suitable enough” class has a score of 3, the “suitable with conditionals” class has a score of 2, and the class “not suitable” has a score of 1. Based on the measurement result, the “suitable” areas were Station 7 (Front of Muara Mati), Station 8 (Outermost Muara Mati), Station 11 (Muara Kuntul), and Station 12 (Front of Muara Kuntul). The coverage area that was in a suitable area category is 962.72 Ha (9.63 km2). The location also linear with the result based on salinity, DO, and transparency (Secchi dish transparency). There are selected locations compared with other stations in Muara Gembong coastal waters because those locations face waste problems from Citarum Watershed and Jakarta Bay. Also, the sites serve as a source of livelihood for the community.
Potential development of fairy shrimp Streptocephalus spp. as aquaculture live feed in Indonesia
Authors: Pratama I , Albasri H , Abinawanto
Published: July 2020

The use of fairy shrimp (Streptocephalus spp.) as a live feed for aquaculture is not well-known in Indonesia. On top of that, fairy shrimp mostly portrayed incorrectly in Indonesia as an unwanted creature and should be prevented in fish ponds. This review highlights the importance of fairy shrimp Streptocephalus spp. as an alternative live feed as well as explore the potential application and suitability for its future implementation in Indonesian aquaculture industry.
The effect of limb-removing and placement-depth on the growth rate of mud crab juvenile, Scylla tranquebarica
Authors: Gunarto  , Sulaeman  , Herlinah
Published: July 2020

Mud crabs, Scylla tranquebarica cultured in brackishwater ponds need three to four months to achieve marketable size. However, rapid movement and cannibalism seemed to be responsible for causing low survival rate of mud crabs. Therefore, a rearing system that can control movement and cannibalism in the crab’s grow-out system is needed. The purpose of the study was to evaluate the growth performance of mud crabs with limb-removing and non-limb- removing were grown in plastic boxes and placed in the different water depths. Two factors were tested namely, first factor is mud crabs with limb-removing, which consists of two levels, A1). All limbs were not removed and A2). All limbs were removed except for swimming legs. The second factor is placement-depths for the crabs growth in brackishwater ponds which have three levels, namely, B1). 0 cm, B2). 35 cm and B3). 70 cm under surface of pond waters. The crabs with mean weight 88.99±5.895 g were tested in each treatment with three replications. The crabs were fed with chopped trasfish at 5% of total weight−day. The experiment lasted after 42 days. The molt crabs were observed daily and the crab growth was monitored every week by measuring their weight. The final weight, weight gain, and specific growth rate were compared among treatments tested. The water quality in the pond, (temperature, salinity, dissolved oxygen, and pH) were also observed. The results showed that 100% of crabs with removed their limb (A2) were molting, while crabs with unremoved their limb (A1) 44.44% were molt. The highest weight gain obtained in A1B3 (61.61 g/ind.) from crabs unremove their limb and placed at a depth of 70 cm under water surface and showed a significant difference (P<0.05) with A1B1 (the crab unremoved their limb and placed on the water surface with weight gain is 9.6g/ind. However, limb-removing and the interaction between limb-removing and placement-depths were not significantly different (P>0.05). The range of water quality such as salinity (17-25 ppt), dissolved oxygen (2.71-8.51 mg/L), water temperature (28.5-31.5°C), and pH (7.5-8.5) in this study are still within the tolerance limit for crab juvenile growth. The unremoved limb crabs and growth at 70 cm as the better alternative to eliminates violation of animal ethics by removing the limb crab.
Activity Budgets, Energy Expenditures, and Energy Intakes of Nesting Ferruginous Hawks
Authors: Wakeley James S.
Published: July 2020

Daily energy expenditures of two pairs of nesting Ferruginous Hawks were estimated from activity budgets, and were compared with energy intakes determined from observed prey captures. In 1974 and 1975 respectively, the adult males expended 330.9 ± 37.8 (SD) and 374.3 ± 18.1 kcal/day, whereas the adult females expended 265.3 ± 28.3 and 294.6 ± 34.5 kcal/day. The total daily energy expenditures of adults and young (approximately 995.8 and 967.1 kcal/day in 1974 and 1975, respectively) were more than balanced by their gross intakes (1,337.8 ± 308.2 and 1,393.2 ± 236.7 kcal/day, respectively). The adult males had foraging efficiencies (kcal gathered/kcal expended in hunting) estimated at 7.56 ± 2.17 in the first year and 7.31 ± 1.80 in the second. Estimates of energy intake and foraging efficiency are maxima due to the likely under-representation of small prey items in regurgitated pellets.
Hummingbird Foraging Behavior at Malvaviscus arboreus Var. Drummondii
Authors: George Mary Wissink
Published: July 2020

Changes in the appearance of Malvaviscus arboreus flowers are associated with changes in nectar reward. Nectar volumes found in day-1 flowers were generally larger and less variable than volumes found in day-2 flowers. Observations of nonterritorial Ruby-throated and Black-chinned hummingbirds (Archilochus colubris and A. alexandri) showed that they distinguished between flowers and preferentially visited the more profitable day-1 flowers. When sucrose solution was added to all day-2 flowers in one Malvaviscus patch, the birds stopped discriminating between flowers the first morning of floral enrichment.

These results indicate that the birds can respond to fairly subtle visual cues when determining the appropriate flowers to visit. The ultimate factor in determining which flowers to continue visiting, however, is the nectar reward. The birds learned to respond differently to the same proximate cue when it was advantageous to do so.
Assessing physical activity and function in patients with chronic kidney disease: a narrative review
Authors: Bakker Esmée A , Zoccali Carmine , Dekker Friedo W , Eijsvogels Thijs M H , Jager Kitty J
Published: July 2020

Physical activity potentially improves health outcomes in patients with chronic kidney disease (CKD) and recipients of kidney transplants. Although studies have demonstrated the beneficial effects of physical activity and exercise for primary and secondary prevention of non-communicable diseases, evidence for kidney patients is limited. To enlarge this evidence, valid assessment of physical activity and exercise is essential. Furthermore, CKD is associated with a decline in physical function, which may result in severe disabilities and dependencies. Assessment of physical function may help clinicians to monitor disease progression and frailty in patients receiving dialysis. The attention on physical function and physical activity has grown and new devices have been developed and (commercially) launched on the market. Therefore the aims of this review were to summarize different measures of physical function and physical activity, provide an update on measurement instruments and discuss options for easy-to-use measurement instruments for day-to-day use by CKD patients. This review demonstrates that large variation exists in the different strategies to assess physical function and activity in clinical practice and research settings. To choose the best available method, accuracy, content, preferable outcome, necessary expertise, resources and time are important issues to consider.
Vocal Distinctiveness and Response to Conspecific Playback in the Spotted Antbird, a Neotropical Suboscine
Authors: Bard Susanne C. , Hau Michaela , Wikelski Martin , Wingfield John C.
Published: July 2020

We studied individual variation in song characteristics of the Spotted Antbird (Hylophylax naevioides), a Neotropical suboscine, and tested for song discrimination using playback of male neighbors and strangers. Discriminant analysis of four frequency and temporal characteristics of the songs of 25 male and five female Spotted Antbirds revealed significant differences among individuals. Each song was assigned correctly to the individual that produced it with over 70% accuracy. However, during field playback, male Spotted Antbirds did not discriminate between neighbor and stranger song. Our results suggest that selection has not favored the evolution of neighbor-stranger discrimination, perhaps because all conspecific intruders pose a threat. The temporal characteristics of Spotted Antbird songs differed significantly between the sexes, but frequency characteristics did not. Females responded significantly less strongly to male playback than males, suggesting that each sex plays a distinct role in territorial defense.

Variación Individual del Canto y Respuesta al Playback Coespecífico en Hylophylax naevioides, un Suboscino Neotropical

Resumen. Estudiamos la variación individual de las características del canto de Hylophylax naevioides, un suboscino neotropical y evaluamos si esta especie responde de forma diferente al playback de individuos vecinos o desconocidos. Un análisis discriminante de cuatro características temporales y espectrales del canto de 25 machos y cinco hembras de H. naevioides reveló que existían diferencias significativas entre individuos. Cada canto fue asignado correctamente al individuo que lo produjo en más del 70% de los casos. Sin embargo, en un experimento de playback en el campo los machos no distiguieron entre el canto de inidividuos vecinos y desconocidos. Estos resultados sugieren que la selección no ha favorecido la evolución de la discriminación entre vecinos y desconocidos porque todos los intrusos coespecíficos suponen una amenaza. Las características temporales, pero no las espectrales, del canto de los H. naevioides difirieron significativamente entre ambos sexos. Las hembras respondieron significativamente menos que los machos al playback con cantos de machos, lo que sugiere que cada sexo desempeña un papel diferente en la defensa del territorio.
Early Intervention With Vedolizumab and Longer-term Surgery Rates in Crohn’s Disease: Post Hoc Analysis of the GEMINI Phase 3 and Long-term Safety Programmes
Authors: Dulai Parambir S , Peyrin-Biroulet Laurent , Demuth Dirk , Lasch Karen , Hahn Kristen A , Lindner Dirk , Patel Haridarshan , Jairath Vipul
Published: July 2020

Background

Crohn’s disease [CD] is a chronic inflammatory bowel disease that, with progression, may require surgical intervention.

Aim

To determine whether vedolizumab treatment of CD earlier in the disease course [≤2 or ≤5 years of disease duration] influences risk of CD-related surgery after accounting for probability of response.

Methods

Post hoc analyses of data from CD patients treated with vedolizumab in the GEMINI 2, GEMINI 3, and GEMINI LTS trials [N = 1253] evaluated CD-related surgery [bowel resection or colectomy] with stratification by probability of response to vedolizumab [low/intermediate or high]. Analyses used a previously validated clinical decision support tool and both logistic regression and Cox proportional hazard analyses.

Results

In total, 113 [9.0%] vedolizumab-treated patients required CD-related surgery. Surgical rates were 6.1% and 9.8% for the high and low/intermediate probability of response groups, respectively. Risk of surgery was lower for patients with a high probability of response versus those with a low/intermediate probability of response (hazard ratio [HR] 0.50, 95% confidence interval [CI] 0.29 to 0.85). For patients with a low/intermediate probability of vedolizumab response, there was a consistent trend for association between earlier treatment [≤2 or ≤5 years since diagnosis] and a lower risk of surgery relative to later treatment (≤2 years versus >2 years: odds ratio [OR] 0.77, 95% CI 0.38 to 1.58; ≤5 years versus >5 years: OR 0.61, 95% CI 0.37 to 1.00].

Conclusions

Earlier intervention with vedolizumab may be associated with lower rates of surgery. Use of the clinical decision support tool may help identify patients most likely to benefit from earlier intervention with vedolizumab.
Short-term treatments for acute cardiac care: inotropes and inodilators
Authors: Guarracino Fabio , Zima Endre , Pollesello Piero , Masip Josep
Published: July 2020

Acute heart failure (AHF) continues to be a substantial cause of illness and death, with in-hospital and 3-month mortality rates of 5% and 10%, respectively, and 6-month re-admission rates in excess of 50% in a range of clinical trials and registry studies; the European Society of Cardiology (ESC) Heart Failure Long-Term Registry recorded a 1-year death or rehospitalization rate of 36%. As regards the short-term treatment of AHF patients, evidence was collected in the ESC Heart Failure Long-Term Registry that intravenous (i.v.) treatments are administered heterogeneously in the critical phase, with limited reference to guideline recommendations. Moreover, recent decades have been characterized by a prolonged lack of successful innovation in this field, with a plethora of clinical trials generating neutral or inconclusive findings on long-term mortality effects from a multiplicity of short-term interventions in AHF. One of the few exceptions has been the calcium sensitizer and inodilator levosimendan, introduced 20 years ago for the treatment of acutely decompensated chronic heart failure. In the present review, we will focus on the utility of this agent in the wider context of i.v. inotropic and inodilating therapies for AHF and related pathologies.
Carotid artery plaque composition and distribution: near-infrared spectroscopy and intravascular ultrasound analysis
Authors: Horváth Martin , Hájek Petr , Štěchovský Cyril , Honěk Jakub , Veselka Josef
Published: July 2020

Most atherosclerotic plaques (APs) form in typical predilection areas of low endothelial shear stress (ESS). On the contrary, previous data hinted that plaques rupture in their proximal parts where accelerated blood flow causes high ESS. It was postulated that high ESS plays an important role in the latter stages of AP formation and in its destabilization. Here, we used near-infrared spectroscopy (NIRS) to analyse the distribution of lipid core based on the presumed exposure to ESS. A total of 117 carotid arteries were evaluated using NIRS and intravascular ultrasound (IVUS) prior to carotid artery stenting. The point of minimal luminal area (MLA) was determined using IVUS. A stepwise analysis of the presence of lipid core was then performed using NIRS. The lipid core presence was quantified as the lipid core burden index (LCBI) within 2 mm wide segments both proximally and distally to the MLA. The analysed vessel was then divided into three 20 mm long thirds (proximal, middle, and distal) for further analysis. The maximal value of LCBI (231.9 ± 245.7) was noted in the segment localized just 2 mm proximally to MLA. The mean LCBI in the middle third was significantly higher than both the proximal (121.4 ± 185.6 vs. 47.0 ± 96.5, P < 0.01) and distal regions (121.4 ± 185.6 vs. 32.4 ± 89.6, P < 0.01). Lipid core was more common in the proximal region when compared with the distal region (mean LCBI 47.0 ± 96.5 vs. 32.4 ± 89.6, P < 0.01).
Assessment of the microbiological quality of natural mineral waters according to the manufacturing time of 20 L returnable packs in Brazil
Authors: Luz Isabelle da Silva , Vasconcellos Luiza , Medeiros Valéria de Mello , Miranda Catia Aparecida Chaia , Rosas Carla de Oliveira , Pimenta Márcia Maria Araújo , Ferreira Fernando César , Romão Célia Maria Carvalho Pereira Araújo , Brandão Marcelo Luiz Lima , Miagostovich Marize Pereira
Published: July 2020

This study aimed to assess the microbiological quality of natural mineral waters commercialized in 20 L returnable packs in Brazil by investigating the presence of bacteria and viruses in packs with different manufacturing times (Tm). With this purpose, 99 water samples from 33 lots (n = 3/batch) of 15 brands, obtained from packs with three intervals of Tm, were analyzed. Total coliforms (16.2%), Pseudomonas aeruginosa (9.9%), sulphite-reducing Clostridium (5.0%) and Escherichia coli (2.0%) were detected but enterococci and norovirus GII not. Regarding brands, 11 (73.3%) presented unsatisfactory results for at least one of the lots analyzed. Pseudomonas aeruginosa analysis revealed six sequence types and strains were susceptible to all antibiotics tested and were able to produce biofilms. Human adenovirus (4) and norovirus GI (9) were also identified in nine samples randomly selected. Natural mineral waters commercialized in 20 L packs with Tm ≥ 2 years presented more microbiological contamination (P ≤ 0.012) than ones with a Tm of 0–1 year or a Tm of 1–2 years. These results suggest that the validity period of reusable 20 L packs should be reduced or that they can no longer be reused.
The ups and downs of traps: environmental impacts, entanglement, mitigation, and the future of trap fishing for crustaceans and fish
Authors: Stevens Bradley G
Published: July 2020

Fishing has many types of impacts on the marine environment. Degradation of seafloor habitats by trawling has been widely studied, along with bycatch mortality, and ghost fishing by traps. Traps or pots are commonly used for catching crustaceans and other organisms, but little research has been conducted on the environmental impacts of trap fishing. Trap fishing causes direct impacts on benthic habitats during setting and retrieval, including dragging along the seafloor, which can lead to the damage and destruction of habitat components such as corals, sponges, and other epifauna. Lines connecting multiple traps increase the overall footprint and cause additional damage. Lost traps and debris can cause damage to coral, submerged aquatic vegetation, and epifauna, especially if moved by storms. Although the trap footprint is small, movement of the trap can expand the impact footprint by an order of magnitude. Trap lines cause whale entanglement and death, and there is much interest in reducing the number of vertical lines as well as their potential for entanglement. New technologies for deploying, locating, and recovering traps are now being developed. The future of trap fisheries will require research on new ways to reduce their negative impacts on benthic and pelagic resources.
Determination of Oxytetracycline Residues in Matrixes from a Freshwater Recirculating Aquaculture System
Authors: Carson Mary C , Bullock Graham , Bebak-Williams Julie
Published: July 2020

This paper describes related procedures to determine the amount of oxytetracycline (OTC) present in trout tissue (muscle with skin attached), biofilter sand, sediment, and tank water from a recirculating aquaculture system. OTC was extracted from the matrixes by different techniques, depending on complexity of the matrix and desired OTC detection level in that matrix. Listed in order of increasing complexity, OTC was extracted from tank water by dilution with acidic buffer containing ethylenediaminetetraacetic acid (EDTA); from biofilter sand by shaking with 0.1N HCl; from sediment by homogenization and shaking with buffer/EDTA; and from ground trout by homogenization and shaking with buffer/EDTA (twice), with further cleanup and concentration of the extract on a polymeric solid-phase extraction cartridge. The 4 procedures all used the same reversed-phase gradient chromatography on a polymeric column with UV detection at 350 nm. The lower limit of detection (estimated) and upper limit of validation for each of these 4 matrixes were 0.04–4.0 μg/g (ppm; trout), 0.03–20 ppm (biofilter sand), 1–6000 ppm (sediment), and 0.003–10 ppm (water). Recoveries ranged from 82 to 108%, with relative standard deviation <20% over the applicable concentration ranges. These procedures were used to monitor OTC residues resulting from medicated feed administered to rainbow trout in a recirculating aquaculture system.
Comparison of Partial Digestion Procedures for Determination of Ca, Cr, Cu, Fe, K, Mg, Mn, Na, P, and Zn in Milk by Inductively Coupled Plasma-Optical Emission Spectrometry
Authors: Kira Carmen S , Maio Franca D , Maihara Vera A
Published: July 2020

A fast procedure was developed for determination of Ca, Cr, Cu, Fe, K, Mg, Mn, Na, P, and Zn in milk samples. This procedure consisted of a partial digestion with hydrochloric acid on a hot plate. The results obtained were compared with 3 other digestion procedures (dry ashing and 2 microwave digestions). All the procedures showed similar precision levels, with coefficients of variation <10% for most analyzed elements. Accuracy was evaluated by using certified reference materials, and the values obtained were within the confidence intervals for these products. The results obtained were not considered statistically different. The partial digestion on a hot plate with HCl can be very practical for laboratories with relatively large numbers of sample analyses.
Comparison of the Compact Dry EC with the Most Probable Number Method (AOAC Official Method 966.24) for Enumeration of Escherichia coli and Coliform Bacteria in Raw Meats: Performance-Tested MethodSM 110402
Authors: Kodaka Hidemasa , Mizuochi Shingo , Teramura Hajime , Nirazuka Tadanobu , Goins David , Odumeru Joseph , Kokubo Yataro
Published: July 2020

Compact Dry E. coli/Coliform Count (EC) is a ready-to-use test method for the enumeration of Escherichia coli and coliform bacteria in food. The plates are presterilized and contain culture medium and a cold water-soluble gelling agent. The medium should be rehydrated with 1 mL diluted sample inoculated onto the center of the self-diffusible medium, allowing the solution to diffuse by capillary action. The plate can be incubated at 35C for 2024 h and the colonies counted without any further working steps. The Compact Dry EC medium plates were validated as an analysis tool for determining colony-forming units (CFU) of E. coli and coliform bacteria from a variety of raw meats using 5 different types of raw meats. The performance tests were conducted at 35C. In all studies performed, no apparent differences were observed between the Compact Dry ECmethod and theAOAC Official Method 966.24 results. For the accuracy claim (n = 75), a correlation factor of r2 = 0.93 (E. coli) and r2 = 0.93 (coliform bacteria) could be assigned, as stated in the application for Performance-Tested MethodSM.
The Use of Genetic Typing Methods to Discriminate Among Strains of Vibrio cholerae, V. parahaemolyticus, and V. vulnificus
Authors: Staley Christopher , Harwood Valerie J
Published: July 2020

This review article summarizes the findings of recent typing studies conducted on Vibrio cholerae, V. parahaemolyticus, and V. vulnificus. The DNA-based methods used to type the Vibrio spp. include whole genome approaches, such as pulsed field gel electrophoresis (PFGE), ribotyping, and repetitive extragenic palindromic (REP)-PCR, single gene targets, and multiple gene targets (multilocus approaches). The goals of these studies include establishing the relatedness of isolates from disease epidemics, discriminating among strains with more or less potential to cause disease or epidemics, and exploring the population biology of these waterborne pathogens. PFGE was consistently among the more discriminatory of the typing methods for all three Vibrio spp., and was useful for tracing the temporal and geographic relatedness of epidemic strains of V. cholerae and V. parahaemolyticus. However, PFGE did not group V. vulnificus strains according to the genotypes that have been proposed as markers of virulence potential. Typing methods that target repetitive elements distributed throughout the genome, such as BOX-PCR and REP-PCR, and DNA sequence-based methods, such as multilocus sequence typing, were also highly discriminatory and, in some cases, superior to PFGE for phylogenetic analysis and identification of strains with high epidemic or virulence potential. As typing methods and strategies are refined and used, the epidemiology, virulence potential, and ecology of these pathogenic Vibrio spp. will become better understood.
Determination of Third-Generation Synthetic Cannabinoids in Oral Fluids
Authors: Sorribes-Soriano Aitor , Verdeguer Josep , Pastor Agustín , Armenta Sergio , Esteve-Turrillas Francesc A
Published: July 2020

A procedure has been developed for the determination of third-generation synthetic cannabinoids in oral fluid samples by using a semi-automated microextraction by packed sorbent (MEPS) procedure and gas chromatography–mass spectrometry (GC–MS) determination. Five synthetic cannabinoids were employed as model compounds 5F-ADB, MMB-CHMICA, THJ-2201, CUMYL-4CN-BINACA and MDMB-CHMCZCA. The most adequate operative conditions for MEPS were evaluated giving quantitative recoveries, from 89 to 124%, in synthetic and field saliva samples spiked with 125 and 250 μg/L of the studied cannabinoids, with the exception of MDMB-CHMCZCA in field saliva samples that provided slightly lower recoveries from 62 to 66%. A high sensitivity was obtained for the proposed MEPS-GC–MS procedure with limits of detection from 10 to 20 μg/L. The obtained results demonstrate the high potential of MEPS-GC–MS combination for semi-automated, selective and sensitive determination of synthetic cannabinoids in oral fluid samples.
477. Characterization of Extended-Spectrum Β-Lactamase (ESBL) Producing Gram-negative (GN) Urinary Tract Infections (UTI) in Pediatric Patients
Authors: Stach Leslie , Orbach Regina , Mongkolrattanothai Kanokporn
Published: July 2020

Background

There has been an increase in antimicrobial resistance among GN pathogens, not only in adults, but also pediatrics. UTIs are common in pediatrics; however, reports of pediatric UTI with ESBL producing GN are limited.

Methods

All urine cultures positive for ESBL producing GN from 5/1/18 to December 31/18 were retrospectively reviewed. Proven infection (PI) defined as ≥50,000 colony-forming units (CFU)/mL of bacteria plus pyuria or positive leukocyte esterase for catheterized or clean catch specimens. Relapsed infection defined as same pathogen cultured within 30 days of infection. Abnormal urinary tract systems or functions (AUTS) include neurogenic bladder, structural anomalies, or intermittent catheterization.

Results

A total of 107 urine cultures for ESBL producing GN, from 85 patients, were included. Majority of specimens [78/107 (73%)] were obtained from the ED or outpatient clinics. 43% of specimens were from patients with AUTS. E. coli was the majority (95%) of ESBL isolates. 57% of ESBL producing GNs were susceptible to amoxicillin/clavulanate (AC) or trimethoprim/sulfamethoxazole (TMP/SMX). 88% were nitrofurantoin susceptible. Only 1 isolate was meropenem resistant. Antibiotics (ABX) were prescribed for UTI in 67/107 episodes. However, only 52 episodes were PI. Of these, 38 were empirically treated with oral ABX and 29 with intravenous ABX. The most commonly prescribed empiric ABX was oral cephalexin (25/67, 37%.) Ineffective empiric ABX for UTI was very common, 83% (43/52). Of these, 5/43 never received effective therapy and none had relapse. Most common duration of ABX was 10 days (range 5–17 days.) 43% (23/52) of PI were treated with oral AC or TMP/SMX. 15% (8/52) of PI were treated with nitrofurantoin. 12% of PI were treated with a once-daily aminoglycoside. Only 6% of PI were treated with a carbapenem.

Conclusion

Many ESBL UTI isolates remain susceptible to oral ABX. Although small numbers, patients treated with ineffective ABX did not return with relapsed infection. Non-carbapenem ABX are a reasonable option to minimize selective pressure or unnecessary use. Empiric narrow-spectrum antibiotic therapy may still be appropriate.

Disclosures

All authors: No reported disclosures.