bluuebunny/crossref_metadata_2025 huggingface dataset:
Technical Condition Estimation of the Gas Turbine Axial Compressor
Authors: Blinov V L , Deryabin G A
Published: February 2022

The paper describes an approach for determining the technical state of an axial compressor as part of a gas turbine unit, based on thermogasdynamic parameters that are measured at the operating facility. As a criterion for the technical condition, it is proposed to use the ratio of the actual efficiency of an axial compressor to the reference efficiency in such modes. To do this, it is enough to know the temperatures and pressures of the air at the inlet and outlet of the axial compressor. A method for selecting such modes is described and some features of filtering the operating parameters of a gas turbine plant are noted. In the proposed approach, the choice of modes for analyzing the technical state of an axial compressor is carried out according to the value of the effective power of the gas turbine unit. Some results of determining the criterion of the technical condition of an axial compressor for a gas turbine unit, which drives a centrifugal compressor of natural gas, are presented. Based on the analysis of the degradation of the technical condition criterion, it is possible to determine its predicted value. The results of the work can be used to create automated systems for assessing and predicting the technical condition of drive gas turbine units at their facilities. The application of the obtained results of the work expands the possibilities of servicing gas turbine plants according to the actual state. The proposed approach can be adapted and applied for gas turbine plants for various purposes, as well as for their individual units.
Features of the chemical composition and structure of bentonites in Tatarstan
Authors: Buntin A E , Sirotkin O S , Sirotkin R O
Published: February 2022

The article studies the chemical, mineralogical, granulometric composition and type of chemical bond, as well as meso- and macrostructure of bentonite of the Nurlat deposit of the Republic of Tatarstan. By laser diffraction, the average particle size in the studied bentonite was found to be dominated by fractions of particles with a size of less than 10 µm (31.18%) and 10-40 µm (36.99%). The average particle size of bentonite was 45.67 µm. According to X-ray analysis, bentonite is mineralogically represented by montmorillonite with an interplane distance of 15.0 Å (001), muscovite, chlorite, kaolinite, clinoptilolite, albite and quartz. The microstructure of bentonite is formed mainly by large anisometric flattened microaggregates and volumetric isometric aggregates up to 70 µm. The average pore size was 0.23 µm, porosity was 39.2%. The microstructural model was cellular with elements of a spongy structure.
Physical and Mathematical Modeling and Computer Analysis of Radial Impellers for Chemical and Power Engineering, taking into account Ecology
Authors: Repetckii O V , Cuong Hoang Dinh
Published: February 2022

This article is devoted to mathematical models for the study of natural frequencies, static stresses of radial impellers with cover disk for chemical and power engineering, taking into account ecology and their modeling by the finite element method. General form and mathematical model based on the finite element method of a radial impeller with a covering disc from Schiele & Co (Germany). For a numerical study, this wheel is accepted in the technical field in different computing software systems. For example, commercial systems such as ANSYS WORKBENCH, SOLIDWORKS and initiative software packages (BLADIS+) [1] for solving problems of statics, vibrations and calculating the resource of different technical systems. Calculations of natural frequencies and static stresses of a radial impeller of 10 blades for chemical engineering are presented. The results obtained in this work can be safely assumed the study of changes in natural frequencies and static stresses of turbomachines are relevant at the design and refinement stages. These computer calculations make it possible to significantly reduce the volume of expensive experimental studies that pollute the environment, reduce design time and improve ecology.
Oil strata formation of small oil deposits in the western part of the Tatarstan republic
Authors: Korolev E A , Eskin A A , Muzalevskaya L V , Barieva E R , Serazeeva E A
Published: February 2022

Small oil fields in the western part of the Tatarstan Republic, localized within single brachyanticlinal structures, have been studied. The main productive oil deposits are confined to the deposits of the Tournaisian stage. The reservoir rocks are leached lumpy-peloid limestones, grainstones. Oil-saturated limestones are predominantly medium- and high-capacity reservoirs. Within the limits of oil deposits, oils are characterized by a weak oxidation state. Their composition is dominated by the middle fractions of hydrocarbons. Only in the bottom part of oil deposits near the oil-water contact is the prevalence of heavy hydrocarbons. This indicates that the oil deposits are in the early stages of formation water flooding. By analogy with the same small oil fields on the eastern side of the Melekesskaya depression, it can be expected that oil inflows will not exceed 6-8 tons/day.
Oil cluster: production, transportation and processing (regional experience)
Authors: Zhichkin K A , Zhichkina L N , Matveeva V V , Vlasova E S , Sh Suleymanova A , Fomenko N L
Published: February 2022

The article examines the role of the oil cluster in the economy of the Samara region. Due to him in 2018-2019. formed about 19% of the gross added value of the region. It unites production, transportation, and oil refining, forming the regional budget, providing employment for the population. The work purpose is to study the oil industry state in the Samara region and determine the features of its development. Within the framework of this study, it is planned to solve the following tasks: - study of statistical data on the Samara region oil cluster state; - identification of patterns and dependencies of its development; -identification of the strengths and weaknesses of the Samara region as an oil-producing territory. The volume of oil production reached 16 million tons of oil per year, and there is a tendency towards its increase. At the same time, the cost of production and electricity consumption are increasing, which indicates the improvement of production technology, the formation of a modern infrastructure of the industry. The problem of inappropriate use of agricultural land under the facilities of the oil sector is emerging. Most of this land is located in the eastern part of the region. In the future damage should reach almost 2.0 billion rubles in year.
Evaluation of the dielectric strength of the insulation of innovative busbar conductors with a voltage class of 6 (10) kV
Authors: Kovalev D I , Voronkova E M , Golubev D V
Published: February 2022

The article discusses the issue of increasing the dielectric strength of solid insulation of conduits used in various areas of the electric power industry, chemical and metallurgical industries, as well as in the agro-industrial complex. For a conductor with a voltage class of 6 (10) kV with a specially developed new type of insulating compound, electric strength tests were carried out with a full lightning impulse and one-minute power frequency voltage. As a result of the tests carried out, the functionality of the improved design and the new type of insulation was confirmed.
Computer technology applications to calculate the insolation of photoelectric power plant
Authors: Konovalov Yu V , Khaziev A N
Published: February 2022

The article considers the method of calculating solar insolation, the algorithm and the program operation for calculating insolation, the graphs are obtained showing the change in solar radiation due to the influence of weather factors and the location of solar-heat collectors installation. The results of the study of the regionally adapted photoelectric power plant using the developed computer model in the Simulink program are presented. The developed model allows to investigate the influence of the main input parameters, such as: latitude and longitude of the power plant installation, difference between the local official time and Greenwich Mean Time, inclination angle of the solar panel, the simulated day, atmospheric transparency factor, albedo and azimuth angle on the insolation intensity of the photoelectric power plant. The obtained dependences can be taken into account in the optimization of power supply systems that use solar energy conversion.
Approach for the modelling of the compressor’s defective blades with numerical simulation methods
Authors: Blinov V L , Zubkov I S , Belyaev O V
Published: February 2022

The current work presents the intermediate results of model development to assess the impact of various defects on the axial compressor operation. Recommendations for adjusting computational models are proposed to conduct gas-dynamic and strength studies of compressor stages and blades, taking into account various defects: verification for the presented models was carried out, which results are also presented in the paper. Based on the verification calculations results some features of CFD modeling are considered, as well as requirements for the investigated defects are indicated. The Discussion section presents the defects classification according to their influence on the compressor operation, which studying is possible using a specially developed mathematical description of blade profiles and blades geometry, as well as considering all the recommendations for computational model adjusting and a general approach to blades modeling defects.
Systematization and monitoring of quality parameters of overhead power transmission lines functioning
Authors: Listyukhin V A , Pecherskaya E A , Safronova O A , Artamonov D V
Published: February 2022

On the basis of quality control methods, the analysis of the causes of technological disturbances (accidents) on overhead power lines was carried out. In particular, the Ishikawa diagram, the Pareto diagram were developed, which made it possible to systematize the main causes of technological violations. The necessity of monitoring the indicators of the reliability of the functioning of overhead power transmission lines by means of information-measuring systems has been substantiated. The structure of an information-measuring system for monitoring parameters that have a negative impact on the functioning quality of overhead power transmission lines is proposed. The proposed system is aimed at ensuring the reliability of the electrical networks operation and improving the quality indicators of services provided to consumers for the transmission of electrical energy.
Assessment of the resource of elements of transportation machins operated in mining energy enterprises
Authors: Umirzokov A M , Abdullo M A , Jobirov F I , Saidullozoda S S , Tashripov A B
Published: February 2022

In mining energy enterprises located at altitudes over 1000 meters above sea level, transport machines are operated in harsh road-climatic conditions, contributing to accelerated wear of equipment and machinery elements. The purpose of the study is related to the assessment and adjustment of the resource of the elements of transport machines operated in mining energy enterprises. The work is devoted to the assessment of the intensity of wear of the elements of machines involved in the transportation of rocks, taking into account the influence of the most significant factors. To assess the resource of elements of transport machines operated in mining energy enterprises, a complex scientific approach was used, taking into account the influence of various combinations of significant factors. The practical significance of the work is associated with planning the need for elements of transport machines operated in mining energy enterprises. The research results, including the simplified mathematical model presented in the article, can be recommended for assessing and adjusting the resource of the elements of transport machines operated in mining energy enterprises.
Reducing environmental hazards in the elimination of oil spills through the use of sorption materials based on polyurethane foams containing waste from agricultural and polymer industries
Authors: Ianov V V , Zenitova L A , Ivanova M A
Published: February 2022

The work is devoted to the development of a sorption material based on elastic polyurethane foam (PUF) containing waste from agricultural and polymer industries. The fillers were fruit shells of buckwheat grains, rice, acacia sawdust, fruit shells, rice straw, walnut shells and ground corn cobs, hardwood sawdust, polymeric waste of expanded polystyrene foam. Oil from the Romashkinskoye field (Tatarstan) was used as a pollutant. The optimal mass ratio of the components of the material A of the PPU component: B of the PPU component: filler = 1: 0.6: 0.16-0.72 (depending on the type of filler) has been determined. The best absorbing capacity of ∼ 13 g / g is possessed by a material based on polyurethane foam and rice straw. Sorption material for cleaning aquatic ecosystems has a high absorbing capacity not only for petroleum products (diesel fuel, industrial oil), but also for products of inorganic origin (vacuum oil). The sorption material is selective and has a higher absorption capacity with respect to oil than to water, the coefficient of selectivity of absorption is 0.4 for an exposure time of 120 min. The possibility of utilization of waste sorption material by the method of thermochemical degradation using a destructive agent based on PPU component A was investigated. The resulting destructate is a homogeneous liquid, easily combined with BND 60/90 bitumen with the formation of a homogeneous polymer-bitumen binder.
Considering different methods of thermal utilization of municipal solid waste
Authors: Petropavlovskaya V K , Shishkov A N , Zamaraev S A , Goncharova A V , Zolnikov DA
Published: February 2022

The article discusses the methods of thermal utilization of municipal solid waste. The environmental burden on landfill disposal sites is reduced by waste incineration. At the same time, the production of heat energy occurs with moderately lower environmental impact. The work of an integrated district heating station was considered in the article. The influence of this installation on the environment and the features of the operation of the integrated district boiler house are considered. The study demonstrates the advantages of utilizing municipal waste at an integrated district heating plant over the method of waste incineration in a regular incineration plant.
Increase in environmental safety of recovery boiler
Authors: Kovalev D A , Rusinov L A
Published: February 2022

To improve environmental safety of a recovery boiler (RB) it is suggested to use a monitoring and diagnostic system that allows detecting faults of the normal process mode at early stages and preventing their development in emergency situations. The RB diagnostic model structure was developed and faults and possible abnormal situations in RB were analyzed qualitatively with the use of HAZOP methodology.
Natural gas content of the “Five-meter” coal seam of the Neryungrinskoye field
Authors: Nikolaevich Grib Nikolay , Yurievich Kuznetsov Pavel , Vladislavovna Grib Galina
Published: February 2022

The article examines, analyzes and consolidates the results of research (direct and indirect research methods) of the gas content of the “Five-meter” seam of the Neryungrinsky coal deposit, which is slated for underground mining. The article also presents the criteria that determine the representativeness of the tested samples by the direct method, which allow the introduction of indirect methods for studying the gas content of the “Pyatimetrovy” formation of the Neryungri field without losing the reliability of the results. As a result of the analysis of the factual material and the geological situation at the field, as well as taking into account the data on the current state of open pit mining at the field, the following were identified: the main factors influencing the degree and nature of the gas content of the Pyatimetrovy layer of the Neryungrinskoye field; composition of gases, the inflow of which is expected to enter the mine atmosphere during mining operations to extract coal from the “Five-meter” seam by the underground method. The main results of the research presented in the article are: the identification of two main gas zones of the “Five-meter” formation with the construction of a gas zoning diagram along the depth of the formation; determination of the presence of gas traps at the field with low production rate of free gas, which are determined by the presence of permafrost in the field; establishing the influence of open pit mining at the deposit on the activation of the natural degassing process of the coal seam and its host rocks at the present stage. The quantitative indicators of the methane content of the coal seam in the field have been established, it has been noted that natural gases in the host rocks are identical to those in the reservoir.
Evaluation of solid particle erosion and electrochemical corrosion of plasma-sprayed WC/8YSZ coating on SS316
Authors: Maharajan S , Thomas Rex F Michael , Ravindran D , Rajakarunakaran S
Published: February 2022

Plasma spray coating enhances the corrosion and wear resistance of the stainless steel structures installed in marine applications. Hence, it is imperative to study the effectiveness of various coating combinations on the material’s performance. The present work investigates the effects of three different plasma-sprayed coatings on the wear and corrosive resistance of austenitic stainless steel (SS316). The three compositions of the coating were prepared using (i) Tungsten carbide (WC), (ii) 8 wt%. Yttria Stabilized Zirconia (8YSZ), and (iii) 50 wt%. Tungsten carbide (WC) with 50 wt%. Yttria Stabilized Zirconia (8YSZ). Experiments were conducted as per ASTM G76 to determine the erosive wear with a mixture of high-velocity air and Al2O3 abrasive particles. The corrosive medium used in the electrochemical polarisation tests was 3.5 wt%. NaCl. A scanning electron microscope (SEM) was used to examine the surface morphology of the eroded and corroded coatings. Energy Dispersive x-ray Analysis (EDAX) and X Ray Diffractrometry (XRD) analysis were carried out to reveal the phase composition, elemental distribution, and lattice parameters of uncoated and coated samples. The study reveals that the composite coating (WC + 8YSZ) have superior wear resistance when exposed to a high-velocity erodent. Due to the robust particle adhesion and cohesiveness of the (WC + 8YSZ) composite coating, crack initiation and propagation are rarely found on the surface of the composite coating, as evidenced by the surface wear morphology analysis. Further investigation reveals that the 8YSZ coating has excellent corrosion resistance. The SEM-based corrosive wear topography analysis reveals that the 8YSZ phase on the coated surface acts as a diffusion barrier to the electrolytic medium and a passive protective layer over the coating. Consequently, the micro-chipping of particles during exposure to the corrosive medium is prevented.
A universal Cannon-Thurston map and the surviving curve complex
Authors: Gültepe Funda , Leininger Christopher , Pho-on Witsarut
Published: February 2022

Using the Birman exact sequence for pure mapping class groups, we construct a universal Cannon-Thurston map onto the boundary of a curve complex for a surface with punctures we call surviving curve complex. Along the way we prove hyperbolicity of this complex and identify its boundary as a space of laminations. As a corollary we obtain a universal Cannon-Thurston map to the boundary of the ordinary curve complex, extending earlier work of the second author with Mj and Schleimer [Comment. Math. Helv. 86 (2011), pp. 769–816].
Validation of and Demographically Adjusted Normative Data for the Learning Ratio Derived from the RAVLT in Robustly Intact Older Adults
Authors: Hammers Dustin B , Spencer Robert J , Apostolova Liana G ,   for the Alzheimer’s Disease Neuroimaging Initiative
Published: February 2022

Background

The learning ratio (LR) is a novel learning slope score that was developed to identify learning more accurately by considering the proportion of information learned after the first trial of a multi-trial learning task. Specifically, LR is the number of items learned after trial one divided by the number of items yet to be learned. Although research on LR has been promising, convergent validation, clinical characterization, and demographic norming of this LR metric are warranted to understand its clinical utility when derived from the Rey Auditory Verbal Learning Test (RAVLT).

Method

Data from 674 robustly cognitively intact older participants from the Alzheimer’s Disease Neuroimaging Initiative (aged 54– 89) were used to calculate the LR metric. Comparison of LR’s relationship with standard memory measures was undertaken relative to other traditional learning slope metrics. In addition, retest reliability at 6, 12, and 24 months was examined, and demographically adjusted normative comparisons were developed.

Results

Lower LR scores were associated with poorer performances on memory measures, and LR scores outperformed traditional learning slope calculations across all analyses. Retest reliability exceeded acceptability thresholds across time, and demographically adjusted normative equations suggested better performance for cognitively intact participants than those with mild cognitive impairment.

Conclusions

These results suggest that this LR score possesses sound retest reliability and can better reflect learning capacity than traditional learning slope calculations. With the added development and validation of regression-based normative comparisons, these findings support the use of the RAVLT LR as a clinical tool to inform clinical decision-making and treatment.
Can morphometrics help us predict the diet of land planarians?
Authors: Boll Piter Kehoma , Leal-Zanchet Ana Maria
Published: February 2022

The use of morphometrics for taxonomy and to predict the diet of organisms based on related species has been applied to several groups. In this study, for the first time, we used morphometric data of land planarians to find patterns that could differentiate genera and feeding habits. We examined body shape, pharynx shape, mouth position and the thickness of the cutaneous musculature in 135 species of land planarians. Mouth position was explained, in part, by the position of the dorsal insertion of the pharynx, and transverse circularity by the relative thickness of the cutaneous musculature. The character that best separated genera and diet was the thickness of the cutaneous musculature. A principal components analysis recovered some patterns previously revealed by molecular phylogenetics, with some closely related genera appearing close to each other in the biplot. The same analysis also showed two clearly distinct groups, one of species that feed on woodlice and the other of species that feed on soft-bodied prey. We conclude that morphometrics can help to narrow down the potential prey of geoplaninid land planarians and aid taxonomic studies.
Multi-scale Fisher’s independence test for multivariate dependence
Authors: Gorsky S , Ma L
Published: February 2022

Identifying dependency in multivariate data is a common inference task that arises in numerous applications. However, existing nonparametric independence tests typically require computation that scales at least quadratically with the sample size, making it difficult to apply them in the presence of massive sample sizes. Moreover, resampling is usually necessary to evaluate the statistical significance of the resulting test statistics at finite sample sizes, further worsening the computational burden. We introduce a scalable, resampling-free approach to testing the independence between two random vectors by breaking down the task into simple univariate tests of independence on a collection of $2\times 2$ contingency tables constructed through sequential coarse-to-fine discretization of the sample , transforming the inference task into a multiple testing problem that can be completed with almost linear complexity with respect to the sample size. To address increasing dimensionality, we introduce a coarse-to-fine sequential adaptive procedure that exploits the spatial features of dependency structures. We derive a finite-sample theory that guarantees the inferential validity of our adaptive procedure at any given sample size. We show that our approach can achieve strong control of the level of the testing procedure at any sample size without resampling or asymptotic approximation and establish its large-sample consistency. We demonstrate through an extensive simulation study its substantial computational advantage in comparison to existing approaches while achieving robust statistical power under various dependency scenarios, and illustrate how its divide-and-conquer nature can be exploited to not just test independence, but to learn the nature of the underlying dependency. Finally, we demonstrate the use of our method through analysing a dataset from a flow cytometry experiment.
Reactive astrocytes promote proteostasis in Huntington’s disease through the JAK2-STAT3 pathway
Authors: Abjean Laurene , Ben Haim Lucile , Riquelme-Perez Miriam , Gipchtein Pauline , Derbois Céline , Palomares Marie-Ange , Petit Fanny , Hérard Anne-Sophie , Gaillard Marie-Claude , Guillermier Martine , Gaudin-Guérif Mylène , Aurégan Gwennaëlle , Sagar Nisrine , Héry Cameron , Dufour Noëlle , Robil Noémie , Kabani Mehdi , Melki Ronald , De la Grange Pierre , Bemelmans Alexis P , Bonvento Gilles , Deleuze Jean-François , Hantraye Philippe , Flament Julien , Bonnet Eric , Brohard Solène , Olaso Robert , Brouillet Emmanuel , Carrillo-de Sauvage Maria-Angeles , Escartin Carole
Published: February 2022

Huntington’s disease is a fatal neurodegenerative disease characterized by striatal neurodegeneration, aggregation of mutant Huntingtin and the presence of reactive astrocytes.

Astrocytes are important partners for neurons and engage in a specific reactive response in Huntington’s disease that involves morphological, molecular and functional changes. How reactive astrocytes contribute to Huntington’s disease is still an open question, especially because their reactive state is poorly reproduced in experimental mouse models.

Here, we show that the JAK2-STAT3 pathway, a central cascade controlling astrocyte reactive response, is activated in the putamen of Huntington’s disease patients. Selective activation of this cascade in astrocytes through viral gene transfer reduces the number and size of mutant Huntingtin aggregates in neurons and improves neuronal defects in two complementary mouse models of Huntington’s disease. It also reduces striatal atrophy and increases glutamate levels, two central clinical outcomes measured by non-invasive magnetic resonance imaging. Moreover, astrocyte-specific transcriptomic analysis shows that activation of the JAK2-STAT3 pathway in astrocytes coordinates a transcriptional program that increases their intrinsic proteolytic capacity, through the lysosomal and ubiquitin-proteasome degradation systems. This pathway also enhances their production and exosomal release of the co-chaperone DNAJB1, which contributes to mutant Huntingtin clearance in neurons.

Together, our results show that the JAK2-STAT3 pathway controls a beneficial proteostasis response in reactive astrocytes in Huntington’s disease, which involves bi-directional signalling with neurons to reduce mutant Huntingtin aggregation, eventually improving disease outcomes.
Evaluation of ABT-888 in the amelioration of α-synuclein fibril-induced neurodegeneration
Authors: Hastings Lyndsay , Sokratian Arpine , Apicco Daniel J. , Stanhope Christina M. , Smith Lindsey , Hirst Warren D. , West Andrew B. , Kelly Kaela
Published: February 2022

The accumulation of α-synuclein inclusions in vulnerable neuronal populations pathologically defines Lewy body diseases including Parkinson’s disease. Recent pre-clinical studies suggest poly(ADP-ribose) polymerase-1 activation and the subsequent generation of poly(ADP-ribose) polymer represent key steps in the formation of toxic α-synuclein aggregates and neurodegeneration. Several studies suggest that the inhibition of poly(ADP-ribose) polymerase-1 activity via the poly(ADP-ribose) polymerase-1/2 small molecule inhibitor ABT-888 (Veliparib), a drug in clinical trials for different cancers, may prevent or ameliorate α-synuclein fibril-induced aggregation, inclusion formation and dopaminergic neurodegeneration. Herein, we evaluated the effects of poly(ADP-ribose) polymer on α-synuclein fibrillization in vitro, the effects of ABT-888 on the formation of fibril-seeded α-synuclein inclusions in primary mouse cortical neurons and the effects of an in-diet ABT-888 dosage regimen with the intracranial injection of α-synuclein fibrils into the mouse dorsal striatum. We found that poly(ADP-ribose) polymer minimally but significantly increased the rate of spontaneously formed α-synuclein fibrils in vitro. Machine-learning algorithms that quantitatively assessed α-synuclein inclusion counts in neurons, both in primary cultures and in the brains of fibril-injected mice, did not reveal differences between ABT-888- and vehicle-treated groups. The in-diet administered ABT-888 molecule demonstrated outstanding brain penetration in mice; however, dopaminergic cell loss in the substantia nigra caused by α-synuclein fibril injections in the striatum was similar between ABT-888- and vehicle-treated groups. α-Synuclein fibril-induced loss of dopaminergic fibres in the dorsal striatum was also similar between ABT-888- and vehicle-treated groups. We conclude that additional pre-clinical evaluation of ABT-888 may be warranted to justify further exploration of ABT-888 for disease modification in Lewy body diseases.
Management of Adult Syphilis: Key Questions to Inform the 2021 Centers for Disease Control and Prevention Sexually Transmitted Infections Treatment Guidelines
Authors: Tuddenham Susan , Ghanem Khalil G
Published: February 2022

A panel of experts generated 5 “key questions” in the management of adult syphilis. A systematic literature review was conducted and tables of evidence were constructed to answer these questions. Available data suggest no clinical benefit to >1 dose of benzathine penicillin G for early syphilis in human immunodeficiency virus (HIV)–infected patients. While penicillin remains the drug of choice to treat syphilis, doxycycline to treat early and late latent syphilis is an acceptable alternate option if penicillin cannot be used. There are very limited data regarding the impact of additional antibiotic doses on serologic responses in serofast patients and no data on the impact of additional antibiotic courses on long-term clinical outcomes. In patients with isolated ocular or otic signs and symptoms, reactive syphilis serologic results, and confirmed ocular/otic abnormalities at examination, a diagnostic cerebrospinal fluid (CSF) examination is not necessary, because up to 40% and 90% of patients, respectively, would have no CSF abnormalities. Based on the results of 2 studies, repeated CSF examinations are not necessary for HIV-uninfected patients or HIV-infected patients on antiretroviral therapy who exhibit appropriate serologic and clinical responses after treatment for neurosyphilis. Finally, several important gaps were identified and should be a priority for future research.
A case report of ivabradine used for heart rate control of atrial fibrillation in acute decompensated heart failure
Authors: Hardison Edward , Cox Zachary L , Heckman Katherine , Kelly Patricia A , Lindenfeld JoAnn
Published: February 2022

Background

Achieving pharmacologic rate control in patients with atrial fibrillation (AF) with rapid ventricular response (RVR) can be tricky when the patient’s underlying cardiac function is decreased. We present a case illustrating how ivabradine can be useful in this clinical scenario.

Case summary

A 95-year-old woman with a history of systolic heart failure (HF) presented with acute decompensated HF in AF with RVR. Beta blockade and calcium channel blockade were avoided given her cardiac history, and diuresis with high doses of furosemide was ineffective. Her ventricular response slowed with ivabradine, allowing for rapid decongestion and a safe discharge home.

Discussion

Ivabradine acts on the If current of cardiac pacemaker cells to slow heart rate (HR), and it currently carries a class IIa recommendation to reduce the risk of HF hospitalization and cardiac death in patients with left ventricular ejection fraction ≤35% and a symptomatic HR ≥70 b.p.m. Although current recommendations are for patients in sinus rhythm, ivabradine has a theoretical benefit in patients with AF given its mechanism of action. Because it does not negatively affect inotropy or blood pressure, ivabradine was used in our patient with a good clinical outcome. Our case provides an example of ivabradine’s usefulness in patients with AF in RVR with a history of depressed systolic function.
Cardiorespiratory fitness and the incidence of coronary surgery and postoperative mortality: the HUNT study
Authors: Smenes Benedikte Therese , Nes Bjarne Martens , Letnes Jon Magne , Slagsvold Katrine Hordnes , Wisløff Ulrik , Wahba Alexander
Published: February 2022

OBJECTIVES

Low physical activity and cardiorespiratory fitness are known risk factors for coronary artery disease, but how they affect the risk of undergoing coronary artery bypass graft surgery is not established. We explored how physical activity and estimated cardiorespiratory fitness affect the risk of coronary surgery and postoperative outcome.

METHODS

Participants with no history of coronary disease from the second wave of the Trøndelag Health Study (HUNT2) were cross-linked with the local heart surgery register and the Norwegian Cause of Death Registry. Cardiorespiratory fitness was estimated by a previously developed algorithm using clinical and self-reported information. Fine-Gray competing risk analyses were used to calculate the risk of undergoing isolated coronary surgery across physical activity groups and estimated cardiorespiratory fitness (mL/kg/min) as quintiles and per 1 metabolic equivalent of task (MET) (3.5 mL/kg/min).

RESULTS

We included 45,491 participants. The mean population age was 46.0 [standard deviation (SD) 15.8] years, and the mean estimated fitness was 41.3 (SD 8.9) mL/kg/min. A total of 672 (1.5%) participants underwent coronary surgery during the follow-up period. The risk of undergoing isolated coronary surgery was 26% [95% confidence interval (CI) 3–44] lower for those classified as highly active compared to those classified as least active. Further, an 11% (95% CI 6–15) lower risk per 1-MET (3.5 mL/kg/min) of higher fitness. Finally, we observed a 15% (95% CI 5–23) lower mortality risk after surgery per 1-MET of higher fitness among those undergoing surgery.

CONCLUSIONS

High levels of physical activity and high estimated fitness levels were inversely associated with the risk of developing coronary disease requiring surgery and overall mortality after surgery.
Roles for non-human primate-associated phage diversity in improving medicine and public health
Authors: Gogarten Jan F
Published: February 2022

Mammals harbor trillions of microorganisms and understanding the ecological and evolutionary processes structuring these ecosystems may provide insights relevant to public health and medicine. Comparative studies with our closest living relatives, non-human primates, have provided first insights into their rich bacteriophage communities. Here, I discuss how this phage diversity can be useful for combatting antibiotic-resistant infections and understanding disease emergence risk. For example, some primate-associated phages show a pattern suggesting a long-term co-divergence with their primate superhosts—co-diverging phages may be more likely to exhibit a narrow host range and thus less useful for phage therapy. Captive primates lose their natural phageome, which is replaced by human-associated phages making phages an exciting tool for studying rates of microorganism transmission at human–wildlife interfaces. This commentary tackles avenues for selecting phages for therapeutic interventions based on their ecological and evolutionary history, while discussing frameworks to allow primate-associated phages to be incorporated into the arsenal of clinicians.
Non-vitamin K antagonist oral anticoagulants in patients with valvular heart disease
Authors: Fanaroff Alexander C , Vora Amit N , Lopes Renato D
Published: February 2022

The non-vitamin K antagonist oral anticoagulants (NOACs) dabigatran, rivaroxaban, apixaban, and edoxaban have transformed the management of atrial fibrillation (AF), but are only approved by regulatory authorities for stroke prophylaxis in patients with so-called “non-valvular AF.” This terminology has spawned confusion about which patients with valvular heart disease benefit from NOACs and which should be treated with vitamin K antagonists (VKAs) instead. Patients with valvular heart disease other than mechanical prosthetic valves or severe mitral stenosis (including those with bioprosthetic valves) were included in pivotal trials demonstrating the benefit of NOACs over VKAs, and consensus guidelines recommend NOACs over VKAs in these patients. Subsequent devoted randomized controlled trials in patients with AF and bioprosthetic valves, including transcatheter valves, have confirmed the safety of NOACs in this population. In patients with rheumatic mitral stenosis, observational studies indicate that NOACs may be safe and effective, but randomized controlled trials are ongoing. By contrast, a randomized controlled trial showed that dabigatran is harmful in patients with mechanical prosthetic mitral valves; however, these data may not extrapolate to patients with mechanical valve prostheses in other locations or to other NOACs, and randomized controlled trials are ongoing. In this review, we discuss these data in greater depth, and make recommendations for the use of NOACs in patients with valvular heart disease.
The Role of Epigenetic Clocks in Explaining Educational Inequalities in Mortality: A Multicohort Study and Meta-analysis
Authors: Fiorito Giovanni , Pedron Sara , Ochoa-Rosales Carolina , McCrory Cathal , Polidoro Silvia , Zhang Yan , Dugué Pierre-Antoine , Ratliff Scott , Zhao Wei N , McKay Gareth J , Costa Giuseppe , Solinas Maria Giuliana , Harris Kathleen Mullan , Tumino Rosario , Grioni Sara , Ricceri Fulvio , Panico Salvatore , Brenner Hermann , Schwettmann Lars , Waldenberger Melanie , Matias-Garcia Pamela R , Peters Annette , Hodge Allison , Giles Graham G , Schmitz Lauren L , Levine Morgan , Smith Jennifer A , Liu Yongmei , Kee Frank , Young Ian S , McGuinness Bernadette , McKnight Amy Jayne , van Meurs Joyce , Voortman Trudy , Kenny Rose A ,   Lifepath consortium, Vineis Paolo , Carmeli Cristian
Published: February 2022

Educational inequalities in all-cause mortality have been observed for decades. However, the underlying biological mechanisms are not well known. We aimed to assess the role of DNA methylation changes in blood captured by epigenetic clocks in explaining these inequalities. Data were from 8 prospective population-based cohort studies, representing 13 021 participants. First, educational inequalities and their portion explained by Horvath DNAmAge, Hannum DNAmAge, DNAmPhenoAge, and DNAmGrimAge epigenetic clocks were assessed in each cohort via counterfactual-based mediation models, on both absolute (hazard difference) and relative (hazard ratio) scales, and by sex. Second, estimates from each cohort were pooled through a random effect meta-analysis model. Men with low education had excess mortality from all causes of 57 deaths per 10 000 person-years (95% confidence interval [CI]: 38, 76) compared with their more advantaged counterparts. For women, the excess mortality was 4 deaths per 10 000 person-years (95% CI: −11, 19). On the relative scale, educational inequalities corresponded to hazard ratios of 1.33 (95% CI: 1.12, 1.57) for men and 1.15 (95% CI: 0.96, 1.37) for women. DNAmGrimAge accounted for the largest proportion, approximately 50%, of the educational inequalities for men, while the proportion was negligible for women. Most of this mediation was explained by differential effects of unhealthy lifestyles and morbidities of the World Health Organization (WHO) risk factors for premature mortality. These results support DNA methylation-based epigenetic aging as a signature of educational inequalities in life expectancy emphasizing the need for policies to address the unequal social distribution of these WHO risk factors.
Reflection and transmission coefficients of spherical waves at an interface separating two dissimilar viscoelastic solids
Authors: Liu Xu , Greenhalgh Stewart , Kumar Manjeet , Li Huijian , Liu Bo , Liao Qinzhuo , Huang Xingguo
Published: February 2022

Spherical wave reflection and transmission (R/T) coefficients at an interface are not only of theoretical significance but also play an important role in the amplitude variation with offset (AVO) analysis of wide-angle reflection seismic data and cross-borehole surveys. For sources close to the interface the resulting wavefields cannot be adequately described in terms of a single incident plane wave. Rather, the spherical waves must be viewed as the superposition of an infinite number of plane waves. Moreover, the R/T coefficients for each individual plane wave in viscoelastic media have proven to be more complicated than expected due to the difficulty in selecting the correct vertical slowness. In such attenuating media the R/T coefficients cannot be properly determined by simply replacing the real elastic parameters with their complex viscoelastic counterparts. In this study, the reflection and transmission coefficients of spherical waves at a plane interface separating two dissimilar viscoelastic solids are rigorously investigated. The difficulty in selecting the vertical slowness is shown to be circumvented if the spherical wavefields are calculated from the plane wavefields using the Sommerfeld integral appropriate for the dissipative materials. However, some resulting phase curves of the complex spherical wave R/T coefficients tend to be of opposite sign to the corresponding phase curves of plane waves due to non-uniqueness of the latter for post-critical wave incidence. In this contribution we propose a new definition of spherical wave R/T coefficients for viscoelastic media which differs from the conventional one. Its advantages are that it is not explicitly expressed as a function of the R/T angles, it is valid for both P and S waves, yet it is consistent with the existing definitions of spherical wave R/T coefficients but is more robust. By way of examples we compute both spherical wave reflection coefficients (SWRC) and spherical wave transmission coefficients (SWTC) for two different viscoelastic models. Unlike plane waves, both the SWRC and the SWTC of converted PS waves are found to be non-zero at vertical incidence and may be drastically affected by the existence of longitudinal PS waves which are confirmed by full waveform calculations for the converted PS waves.
Multi-criteria decision-making approach for the selection of cleaning method of solar PV panels in United Arab Emirates based on sustainability perspective
Authors: AlMallahi Maryam
Nooman , El Haj Assad Mamdouh , AlShihabi Sameh , Alayi Reza
Published: February 2022

Solar power has become one of the most essential sources in the move to clean energy production. It plays a vital role in providing environmental, social and economic benefits. As a result, the solar panels must be cleaned consistently. There are several cleaning methods, including passive, active and manual cleaning. In this paper, multi-criteria decision-making method Technique for Order of Preference by Similarity to Ideal Solution is utilized to compare between different cleaning methods and find the optimal cleaning method in Dubai. This approach considers the influential factors and their relative importance of the cleaning methods to prioritize the alternatives. The aim of the work is to consider social, economic and environmental criteria while choosing the appropriate cleaning method for solar photovoltaic (PV) panels. The chosen attributes include several important factors, such as initial and running cost, time required for cleaning, safety, energy required, water consumption, environmental impact and economic impact. The data were collected through a survey of solar energy experts in Dubai. Different weighting methods, such as simple additive weighting and multiplicative exponential weighting were used to determine the relative relevance of the criteria. Sensitivity analysis was conducted, and cost attribute was removed. Inter-criteria correlation, entropy and stochastic dominance were calculated, and the results revealed that robot water-based (sprinkler and brush) cleaning method was the most effective option 0.648, 0.753 and 0.707, respectively. Also the sensitivity analysis results confirmed that robot water based is the most preferred cleaning method by experts in Dubai.
The Online Safety Bill and the Tech Agenda for 2022
Authors:   BCS Policy and PR
Published: February 2022

The Online Safety Bill, which returns to parliament in spring, is likely to define the tech year. Thanks to BCS members and our partners, we’re already part of the debate, and calling for greater clarity on how this legislation will guarantee the accountability it is calling for.
The True Cost of a Charity Data Breach
Authors: Hayes Kingsley
Published: February 2022

Think twice before you send bulk emails, writes Kingsley Hayes, Head of Data Breach at Keller Lenkner UK. Even a single email can cause a significant data breach, which could result in regulatory action, fines and litigation.
Antifungal use in children with acute leukaemia: state of current evidence and directions for future research
Authors: Yeoh Daniel K. , Haeusler Gabrielle M. , McMullan Brendan J. , Butters Coen , Bryant Penelope A. , Clark Julia E. , Cooper Celia M. , Gwee Amanda , Kotecha Rishi S. , Lai Tony , Slavin Monica A. , Thursky Karin A. , Blyth Christopher C.
Published: February 2022

Invasive fungal disease (IFD) remains a common and serious complication in children treated for leukaemia. Antifungal prescription in children with leukaemia presents unique challenges, particularly due to variation in IFD risk between and within leukaemia treatment protocols, drug toxicities and interactions between antifungals and chemotherapeutic agents. With recent advances in the understanding of IFD epidemiology and large clinical trials in adults assessing antifungals for IFD treatment and prophylaxis, together with paediatric clinical and pharmacokinetic studies, there is a growing body of data to inform optimal antifungal use in children. A panel of infectious diseases and haematology-oncology clinicians with expertise in IFD management compiled a list of 10 key clinical questions following development of the 2021 Australia and New Zealand Mycology Antifungal Consensus Guidelines. A focused literature review was conducted to explore available evidence and identify gaps in knowledge to direct future research. With the changing epidemiology of IFD globally, the ongoing evolution of paediatric leukaemia treatment and the increasing availability of novel antifungal agents, advocacy for paediatric clinical studies will remain vital to optimize IFD prevention and treatment in children with leukaemia.