bluuebunny/crossref_metadata_2025 huggingface dataset:
Dynamic dampers of vibrations of inherited-deformable systems with finite number of degrees of freedom
Authors: Abdullaev Zafar , Yusupov Majid , Mirzaev Sayibdjan , Noraliev Nurilla , Kusharov Zohid
Published: August 2020

The problem of dynamic vibration dampers of inherited-deformable systems with finite number of degrees of freedom is considered. Rheological properties of spring (suspension) are taken into account using integral model with Koltunov-Rzhanitsin relaxation core. The behavior of the system with a damper is considered at free attenuation oscillations caused by the specified initial conditions, as well as at constant, pulse and periodic external impacts. The obtained results make it possible to conclude on the expediency of using dynamic dampers to reduce amplitude of oscillations, both in perfectly elastic and in inherited-deformable systems during transient processes. A computational algorithm based on quadrature formulas is used to solve the problem.
Vertical nonlinear oscillations of viscoelastic systems with multiple degrees of freedom
Authors: Karimova Khabiba , Khikmatullaev Sanjar , Kholiyorov Umirzok , Mirjalalov Nuriddin , Islomov Utkir , Juraeva Fotima
Published: August 2020

Vertical oscillations of three loads of different masses connected by nonlinear viscoelastic springs (suspensions) are considered in the paper. An account for rheological properties of the suspension, an integral model with the Koltunov-Rzhanitsyn relaxation kernel is used. Effective computational algorithms have been developed for solving problems based on the use of quadrature formulas. The effect of rheological properties of suspension on the mass displacement from the position of static equilibrium is investigated as well as the influence of nonlinear properties of the suspension on the mode of vibration and frequency.
Energy-saving solutions in the construction and housing and utilities sectors of Russia
Authors: Melnikov Vladimir , Dorofeev Viktor , Gavrilov Michail , Medvedev Maxim
Published: August 2020

As an object of research, the direction of optimizing energy saving and increasing energy efficiency of multi-layer enclosing structures (in particular, external walls) of buildings (with insulation and ventilated facades) was adopted. The high relevance of the research is related to the achievement of rational use (to an optimal level) of material and energy resources (with the correct choice of properties and location of the insulation in the wall). The accepted research method is based on the application of thermal engineering calculation of the external fence and its temperature field, other elements of the building heating system with the establishment of dependencies between the values and comparing them with the standard performance indicators (using the Mathcad program). Specific results of the study include determining the temperature distribution in the thickness of the 5-layer outer wall with fixing the plane with zero temperature of the material, which shows the place of possible freezing in the structure.
Fractal model of “breakthrough” innovation in nanotechnology
Authors: Bukharov D N , Arakelian S M
Published: August 2020

The fractal modeling approach is applied to the distribution process of breakthrough innovation in nanotechnology. For modeling, a diffusion-limited aggregation fractal is used. This model takes into account the change in the probability of adhesion (the ability to perceive innovations) and viscosity (the rate of propagation of innovations). Evaluation of the fractal dimension of the simulated structures allows us to identify trends and predict their further development. The model system reaches a breakthrough jump with a fractal dimension greater than 1.6. The unstable nature of the further development of the system will be observed with a sharp increase in fractal dimension, if the parameters of the ability to perceive innovations and the speed of innovation spread to level 1. Favorable conditions for the technological leap are realized in the case with a slightly lower fractal dimension when the rate of innovation spread is 1. The stable nature of the development of the system is observed at medium rates and above. With general trends below the average, the leap will be difficult to achieve.
The effect of laser cladding modes on the geometrical parameters and adhesion strength of the deposited layer on a steel substrate 08Kh18N10T of corrosion-resistant powder 08Kh17N8S6G
Authors: Gotz A N , Gusev D S , Guskov V F , Zavitkov A V , Lukhter A B , Prokoshev V G , Rumyantcev I V
Published: August 2020

The results of testing samples of steel 08Kh18N10T with deposited tracks and layers of corrosion-resistant powder 08Kh17N8S6G at various laser cladding modes for the development of coating technology for working surfaces of shut-off valves on nuclear and thermal power plants. Laser cladding the steel substrate was carried out on a robotic cladding complex with an ytterbium fiber laser and coaxial powder feed. Laser output, processing speed, mass flow rate and track overlap were variable parameters for evaluating the quality of laser cladding. Macrogeometry was performed on transverse sections, adhesion tests were carried out on special samples using a testing machine. The absence of pores, cracks, undercut by visual inspection and cross section samples, the adhesion strength of the layer to the substrate, penetration depth and clad height are used as quality of coating. Identified cladding parameters having an effect on increasing the clad height, the penetration depth, as a result, the adhesion strength are revealed. Laser cladding modes are selected that provide a deposited layer with a height of more than 1 mm and good adhesive properties.
Effect of part orientation on temperature stresses in the structure of a material during selective laser melting
Authors: Voznesenskaya A A , Kochuev D A , Raznoschikov A S , Zhdanov A V , Morozov V V
Published: August 2020

In this paper, we consider the problems of thermal stress during selective laser melting. Using scanning electron microscopy, the average particle size and shape of the AlSi10Mg powder alloy were revealed. Details of complex geometric shapes have been grown by various construction strategies using the selective laser melting method. In the first case, the influence of supporting structures on the geometric shape of the part was considered. An optimal set of supporting structures has been developed in order to reduce the time spent on machining after selective laser melting, as well as to exclude supports in hard-to-reach cavities. In the second case, the location of the part on the construction platform was considered. It was found that changing the orientation of the parts allows to reduce the volume and number of supporting structures. The results are obtained on thermal stresses occurring in the process of growing a part by selective laser melting.
Design of spaser-like nanoparticle systems for nonclassical optical states generation
Authors: Gubin M Yu , Shesterikov A V , Prokhorov A V
Published: August 2020

The quantum features of photon generation in multiparticle spaser systems consisting of metal nanoparticles and semiconductor quantum dots are investigated. We found the conditions for stationary regime of single-photon generation in spaser systems. In particular, in order to achieve a balance between gain and loss in the system, we determined the chemical and geometric characteristics of nanoparticles and quantum dots by using the optimization algorithm. The strong dipole-dipole interaction between nanoparticles in the spaser system is studied. We show that these conditions can lead to the violation of Cauchy-Schwartz inequality and appearance of nonclassical correlations in the system. The generation of entangled photons in a three-particle spaser system with nonlinear plasmon-exciton interaction is theoretically demonstrated. The introduction of an additional degree of freedom in the form of an external magnetic field leads to a change in the energy levels of quantum dots and provides the possibility to control the quantum properties of generated photons. We proposed the model of an effective subwavelength source of entangled photons controlled by an external magnetic field.
Influence of thermal ageing on creep rupture mechanism and creep life of P92 ferritic steel
Authors: Kang Hui , Shen Junjie , Zhang Shanjun , Han Hongguang , Hu Fuyong , He Biao , Zhao Qingquan , Xiao Gongye
Published: August 2020

In order to analyze the effect of thermal ageing on creep rupture mechanism and establish a method for predicting the creep rupture life of P92 heat-resistant steel under thermal ageing, creep tests were performed on P92 steel specimens, aged at 650 °C for different times under different applied stresses. Optical microscopy and scanning electron microscopy were utilized to observe the microstructure after thermal ageing and creep rupture. Voids and cracks were distributed in the grains of P92 steel before thermal ageing, whereas the voids were clearly distributed around M23C6 precipitates and Laves phase along sub-grain boundaries after thermal ageing. The creep damage tolerance factor of the unaged and short-time aged samples ranged from 2.5 to 5, and the creep rupture was caused by dislocation movement. After high-temperature thermal ageing for 3000 h, the damage tolerance factor increased to > 5 and creep rupture was caused by precipitate coarsening. A theoretical method was established to predict the creep rupture life of heat-resistant P92 steel under thermal ageing, providing consistent results with the American Society of Mechanical Engineers (ASME) long-term test and trend.
Little Voices: The Importance and Limitations of Children’s Histories
Authors: Chapdelaine Robin P.
Published: August 2020

In a complement to the 2020 AHR Roundtable “Chronological Age: A Useful Category of Historical Analysis” (125, no. 2), this AHR Exchange focuses on the history of children and childhood. Sarah Maza presents a critical review essay, highlighting the limiting factors in the expanding field of childhood studies. Children, she observes, produce few sources of their own voices, have limited agency, and as individuals and as a group soon outgrow their subaltern status—they grow up. Robin P. Chapdelaine, Nara Milanich, Steven Mintz, Ishita Pande, and Bengt Sandin—historians representing diverse geographical, theoretical, and methodological perspectives on the history of children and childhood—react to Maza’s observations by bringing up important methodological questions about subjecthood, agency, and modernity. Maza’s rejoinder reflects on these questions and on the possibility of age-based historical agency.
First- and Second-Trimester Reference Intervals for Thyroid Function Testing in a US Population
Authors: Bunch Dustin R , Firmender Kyle , Harb Roa , El-Khoury Joe M
Published: August 2020

Objectives

Thyroid dysfunction in pregnancy is associated with increased risk of adverse outcomes to mother and child. Trimester-specific reference intervals for thyroid function tests are not routinely provided by clinical laboratories. In this study, we present first- and second-trimester-specific reference intervals in a US population for thyroid-stimulating hormone (TSH), free thyroxine (FT4), total thyroxine (T4), and total triiodothyronine (T3) measured on Roche analyzers.

Methods

We used patient samples from first- and second-trimester prenatal screening. Samples were limited to singleton pregnancies and negative screening results for thyroid peroxidase and thyroglobulin antibodies. Analytes (TSH, FT4, T4, and T3) were measured on a Roche Modular e170 then verified on a Roche cobas e801.

Results

The reference intervals established on the e170 and verified on the e801 for the first trimester were 0.16 to 2.82 mIU/L for TSH, 12.0 to 18.5 pmol/L for FT4, 62.8 to 177.9 nmol/L for T4, and 1.5 to 3.4 nmol/L for T3. The reference intervals for the second trimester were 0.40 to 3.62 mIU/L for TSH, 10.2 to 16.6 pmol/L for FT4, 66.6 to 176.0 nmol/L for T4, and 1.56 to 3.6 nmol/L for T3.

Conclusions

This is the first report of trimester-specific reference intervals for thyroid function tests on Roche analyzers in the United States, and it is consistent with worldwide reports.
Medicare Trends in Pathologist Participation, Service Utilization, and Payments
Authors: Arvisais-Anhalt Simone , Araj Ellen , Park Jason Y
Published: August 2020

Objectives

Quantifying pathologist participation in Medicare services may be informative for the prediction of future workforce needs and reimbursement.

Methods

A retrospective examination was performed of pathologist professional (Part B) Medicare billings and payments from 2012 to 2017. The Medicare Provider Utilization and Payment Data: Physician and Other Supplier Public Use File was the primary data source.

Results

From 2012 to 2017, there was an increase (3.7%; 11,215 up to 11,627) in pathologists providing Medicare Part B services. Female pathologists increased from 36.10% to 40.8% of pathologists during this time period. Normalized per pathologist, there was an increase (7.8%; 1,382 up to 1,489) in beneficiaries served as well as an increase (4.1%; 2,442 up to 2,543) in services performed. The top 10 pathology Part B services performed in a facility were all surgical pathology. Although services increased, the overall payment of Part B pathology services decreased (3%; $996,519,358 down to $966,615,856) during the study period.

Conclusions

Although there is increasing pathologist participation in Medicare, the workload per pathologist has increased.
Associations of Height With the Risks of Colorectal and Endometrial Cancer in Persons With Lynch Syndrome
Authors: Brouwer Jesca G M , Newcomb Polly A , Bisseling Tanya M , Figueiredo Jane C , Hopper John L , Jenkins Mark A , Koornstra Jan J , Lindor Noralane M , Vasen Hans F A , Win Aung K , Kampman Ellen , van Duijnhoven Fränzel J B
Published: August 2020

People with Lynch syndrome (LS), who carry a pathogenic mutation in a DNA mismatch repair gene, have increased risks of colorectal cancer (CRC) and endometrial cancer (EC). A high reported variability in cancer risk suggests the existence of factors that modify cancer risk for persons with LS. We aimed to investigate the associations between height and CRC and EC risk for persons with LS using data from 2 large studies. Information on 1,115 men and 1,553 women with LS from the Colon Cancer Family Registry (1998–2007) and the GEOLynch Cohort Study (2006–2017) was harmonized. We used weighted Cox proportional hazards regression models with age on the time axis to estimate adjusted hazard ratios and 95% confidence intervals for each 5-cm increment in self-reported height. CRC was diagnosed in 947 persons during 65,369 person-years of observation, and 171 women were diagnosed with EC during 39,227 person-years. Height was not associated with CRC for either men (per 5-cm increment, hazard ratio (HR) = 1.00, 95% confidence interval (CI): 0.91, 1.11) or women (per 5-cm increment, HR = 1.01, 95% CI: 0.92, 1.11), nor was height associated with EC (per 5-cm increment, HR = 1.08, 95% CI: 0.94, 1.24). Hence, we observed no evidence for an association of height with either CRC or EC among persons with LS.
Reading the “Memoirs of the Life of Florence Hall” ThroughThe Long Songof the Caribbean Colonial Archive
Authors: Aljoe Nicole N
Published: August 2020

This article suggests that we should analyze the mediated and fragmentary narratives of the lives of the enslaved—the predominate format of such texts in the archives—as well as self-written slave narratives. Although not biographical in the same fashion as the self-written texts, these more ephemeral texts can also enhance and productively contribute to our understandings of the literary and discursive features of the era. In order to attend to such texts, we need to develop more dynamic reading strategies for the multiple voices and varied formats common to them. One such strategy is animated by arguments about alternative histories suggested by neo-slave-narrative novels like Andrea Levy’s The Long Song (2011). I suggest that drawing on the models of the imaginative possibilities of neo-slave-narrative fictions, along with conceptually related links to both Edward Said’s hermeneutics of contrapuntal reading and Saidiya Hartman’s exegetics of critical fabulation, reveals how an ephemeral and fragmentary text or “textual splinter” like “Memoirs of the Life of Florence Hall” may yield more complex readings and help us consider what the lives of the enslaved might have looked like, as well as offers portraits of the discursive networks in which it existed.

The … archive was not meant to encode the nuances of Hall’s voice or memories of her experiences. The archive was instead meant to document the power of the establishment and the data that would be useful to its perpetuation.
Comparison of Cellulite Severity Scales and Imaging Methods
Authors: Young V Leroy , DiBernardo Barry E
Published: August 2020

Cellulite is characterized by dimpled contour alterations of the skin and is present in approximately 85% to 90% of postpubertal females. Although the pathophysiology of cellulite remains to be fully elucidated, experimental evidence indicates a multifactorial process involving the number and types of fibrous septae, microvascular dysfunction, subcutaneous inflammation, decreased dermal thickness with age, and fat deposition. Cellulite is a major cosmetic concern for many women, and a number of both noninvasive (eg, massage, cosmeceuticals, laser therapy) and minimally invasive techniques (eg, subcision, collagenase injection) have been evaluated to improve the appearance of the affected skin. However, evidence for many of these treatments is limited, largely due to the lack of a validated, convenient tool for the standardized evaluation of cellulite severity. Various imaging modalities have been employed to characterize cellulite severity and the impact of treatment, but only 2-dimensional and 3-dimensional digital photography have been adequately validated. However, in many cases, imaging findings do not correlate with subjective measures of cellulite severity. A number of cellulite rating scales have been developed; some provide only a qualitative measure, whereas others do not fully capture all clinically relevant aspects of cellulite, including the perspective of the patient. There remains an unmet need for global adoption of a validated scale that can be utilized easily by clinicians and patients in clinical and research settings. We propose features that should be included in an ideal rating scale for assessment of cellulite severity.
Apelin enhances biological functions in lung cancer A549 cells by downregulating exosomal miR-15a-5p
Authors: Ran Jingjing , Li Yan , Liu Lei , Zhu Yihan , Ni Yinyun , Huang Hong , Liu Zhiqiang , Miao Zhiyong , Zhang Li
Published: August 2020

Apelin acts as a tumor promoter in multiple malignant tumors; however, its regulatory mechanism remains unclear. Previous studies have indicated that exosomes are pivotal to mediating tumor progression and metastasis. This study examined whether apelin enhances proliferation and invasion ability of lung cancer cells via exosomal microRNA (miRNA). Lung cancer A549 cells overexpressing apelin and control vector were generated by lentiviral transfection. Exosomes were isolated from the culture supernatant of each cell group and characterized. A-exo and V-exo were, respectively, cocultured with A549 cells, and assays of proliferation, apoptosis, colony formation and invasion were conducted. Exosomal miRNA sequencing (miRNA-seq) was performed on A-exo and V-exo to select a candidate miRNA. It was found that A549 cells absorbed more A-exo than V-exo, and A-exo could promote proliferation, colony formation, migration and invasion of A549 cells more than V-exo. Exosomal miRNA-seq data revealed that miR-15a-5p was markedly lower in A-exo compared with V-exo. Low expression of miR-15a-5p was also found in lung cancer tissues and cell lines, suggesting that miR-15a-5p may have an anti-tumor role. Overexpression of miR-15a-5p in A549 cells was associated with less cell proliferation, migration, invasion and suppressed cell cycle, and lower amounts of CDCA4 (cell division cycle-associated protein 4) indicated that it may be a potential target for miR-15a-5p. This study elucidated a novel regulatory mechanism that apelin may promote proliferation and invasion of lung cancer cells by inhibiting miR-15a-5p encapsulated in exosomes.
Comparison of a Novel Rapid Lateral Flow Assay to Enzyme Immunoassay Results for Early Diagnosis of Coccidioidomycosis
Authors: Donovan Fariba M , Ramadan Ferris A , Khan Sher A , Bhaskara Apoorva , Lainhart William D , Narang Aneesh T , Mosier Jarrod M , Ellingson Katherine D , Bedrick Edward J , Saubolle Michael A , Galgiani John N
Published: August 2020

Background

Coccidioidomycosis (CM) is a common cause of community-acquired pneumonia where CM is endemic. Manifestations include self-limited pulmonary infection, chronic fibrocavitary pulmonary disease, and disseminated coccidioidomycosis. Most infections are identified by serological assays including enzyme-linked immunoassay (EIA), complement fixation, and immunodiffusion. These are time-consuming and take days to result, impeding early diagnosis. A new lateral flow assay (LFA; Sōna; IMMY, Norman, OK) improves time-to-result to 1 hour.

Methods

We prospectively enrolled 392 patients with suspected CM, compared the LFA with standard EIA and included procalcitonin evaluation.

Results

Compared with standard EIA, LFA demonstrates 31% sensitivity (95% confidence interval [CI], 20–44%) and 92% specificity (95% CI, 88–95%). Acute pulmonary disease (74%) was the most common clinical syndrome. Hospitalized patients constituted 75% of subjects, and compared with outpatients, they more frequently had ≥3 previous healthcare facility visits (P = .05), received antibacterials (P < .01), and had >3 antibacterial courses (P < .01). Procalcitonin (PCT) was <0.25 ng/mL in 52 (83%) EIA-positive patients, suggesting infection was not bacterial.

Conclusions

When CM is a possible diagnosis, LFA identified nearly one-third of EIA-positive infections. Combined with PCT <0.25 ng/mL, LFA could reduce unnecessary antibacterial use by 77%.
Potential Antigenic Cross-reactivity Between Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and Dengue Viruses
Authors: Lustig Yaniv , Keler Shlomit , Kolodny Rachel , Ben-Tal Nir , Atias-Varon Danit , Shlush Ekaterina , Gerlic Motti , Munitz Ariel , Doolman Ram , Asraf Keren , Shlush Liran I , Vivante Asaf
Published: August 2020

Background

Coronavirus disease 2019 (COVID-19) and dengue fever are difficult to distinguish given shared clinical and laboratory features. Failing to consider COVID-19 due to false-positive dengue serology can have serious implications. We aimed to assess this possible cross-reactivity.

Methods

We analyzed clinical data and serum samples from 55 individuals with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. To assess dengue serology status, we used dengue-specific antibodies by means of lateral-flow rapid test, as well as enzyme-linked immunosorbent assay (ELISA). Additionally, we tested SARS-CoV-2 serology status in patients with dengue and performed in-silico protein structural analysis to identify epitope similarities.

Results

Using the dengue lateral-flow rapid test we detected 12 positive cases out of the 55 (21.8%) COVID-19 patients versus zero positive cases in a control group of 70 healthy individuals (P = 2.5E−5). This includes 9 cases of positive immunoglobulin M (IgM), 2 cases of positive immunoglobulin G (IgG), and 1 case of positive IgM as well as IgG antibodies. ELISA testing for dengue was positive in 2 additional subjects using envelope protein directed antibodies. Out of 95 samples obtained from patients diagnosed with dengue before September 2019, SARS-CoV-2 serology targeting the S protein was positive/equivocal in 21 (22%) (16 IgA, 5 IgG) versus 4 positives/equivocal in 102 controls (4%) (P = 1.6E−4). Subsequent in-silico analysis revealed possible similarities between SARS-CoV-2 epitopes in the HR2 domain of the spike protein and the dengue envelope protein.

Conclusions

Our findings support possible cross-reactivity between dengue virus and SARS-CoV-2, which can lead to false-positive dengue serology among COVID-19 patients and vice versa. This can have serious consequences for both patient care and public health.
The strange case of urban theory
Authors: Barnett Clive
Published: August 2020

Recent debates in urban theory have centred on the problem of whether universal concepts can have applications to particular places. These debates could benefit from more serious attention to how urban thought involves styles of analogical reasoning closer in spirit to casuistry than to explanatory theory. The difficult status of ‘the case’ in urban studies is explored through a consideration of different types of universality in this field, leading to a re-consideration of ideas of experimentalism and wicked problems. Further attention should be given to the multiple styles of reasoning through which urban knowledge is produced and circulated.
Microbiomes in a manganese oxide producing ecosystem in the Ytterby mine, Sweden: impact on metal mobility
Authors: Sjöberg Susanne , Stairs Courtney W , Allard Bert , Homa Felix , Martin Tom , Sjöberg Viktor , Ettema Thijs J G , Dupraz Christophe
Published: August 2020

Microbe-mediated precipitation of Mn-oxides enriched in rare earth elements (REE) and other trace elements was discovered in tunnels leading to the main shaft of the Ytterby mine, Sweden. Defining the spatial distribution of microorganisms and elements in this ecosystem provide a better understanding of specific niches and parameters driving the emergence of these communities and associated mineral precipitates. Along with elemental analyses, high-throughput sequencing of the following four subsystems were conducted: (i) water seeping from a rock fracture into the tunnel, (ii) Mn-oxides and associated biofilm; referred to as the Ytterby Black Substance (YBS) biofilm (iii) biofilm forming bubbles on the Mn-oxides; referred to as the bubble biofilm and (iv) fracture water that has passed through the biofilms. Each subsystem hosts a specific collection of microorganisms. Differentially abundant bacteria in the YBS biofilm were identified within the Rhizobiales (e.g. Pedomicrobium), PLTA13 Gammaproteobacteria, Pirellulaceae, Hyphomonadaceae, Blastocatellia and Nitrospira. These taxa, likely driving the Mn-oxide production, were not detected in the fracture water. This biofilm binds Mn, REE and other trace elements in an efficient, dynamic process, as indicated by substantial depletion of these metals from the fracture water as it passes through the Mn deposit zone. Microbe-mediated oxidation of Mn(II) and formation of Mn(III/IV)-oxides can thus have considerable local environmental impact by removing metals from aquatic environments.
Health systems effects of successive emergency health and nutrition projects: an embedded retrospective case study analysis in Sudan and Pakistan
Authors: Sarriot Eric , Olivas Elijah , Khalsa Saraswati , Ashraf Sarah , Hejna Emily , Hinds Givan , Story William T
Published: August 2020

Despite increasing attention to the concept of a humanitarian-development nexus in recent years, limited research is available to improve health systems strengthening practice within humanitarian programmes. We used an exploratory, systematic, embedded, multiple case study design to discern systems effects of successive Save the Children chronic emergency health and nutrition projects implemented in Sudan and Pakistan between 2011 and 2018. We used textual analysis to code 63 documents focused on eight themes using NVivo 11.0. This was supplemented by six key informant interviews. Findings offer a complex and mixed picture, with contributions to systems strengthening in community systems, their linkages to health management structures, and human resources for health. Projects with primary mandates for urgent service delivery progressively found systems strengthening opportunities, through a combination of tacit choices and explicit objectives. In both countries, some ‘parallel systems’ were set in place initially, with immediate gains (e.g. quality of services) only occasionally accompanied by enhanced systems capacity to sustain them. Cycles of implementation, however, achieved financial transition of ‘macro-costs’ to the government (e.g. facilities in Sudan, staff in Pakistan) through indirect pathways and the influence of pluralistic governmental structures themselves. Opportunities were taken, or missed, based on dynamic relationships within the government-development partners eco-system. Transition steps also came with unintended effects and drops in intensity. Both project contributions to systems strengthening and our own study were limited by substantial gaps in evaluation and documentation processes. We provide cautious recommendations based on the literature and our two case studies. Even mid-size chronic emergency projects can and should make meaningful and explicit contributions to systems strengthening. This contribution will, however, depend on the development eco-system context, and development of better collective intelligence (coordination, evaluation and learning, benchmarking, accountability) to improve individual projects’ adaptive management efforts to improve fit with evolving national systems.
Effectiveness of a nutrition education and counselling training package on antenatal care: a cluster randomized controlled trial in Addis Ababa
Authors: Omer Afrah Mohammedsanni , Haile Demewoz , Shikur Bilal , Macarayan Erlyn Rachelle , Hagos Seifu
Published: August 2020

The World Health Organization (WHO) recommends the need for a strong nutrition training package for practitioners, including antenatal care (ANC) providers. Without such a training package, ANC visits remain a missed opportunity to address nutritional problems among pregnant women. This study evaluated the effectiveness of an in-service nutrition education and counselling package on the providers’ counselling skills during ANC visits. A cluster randomized controlled trial was conducted in Addis Ababa, Ethiopia. All health-care providers working in ANC units across 20 health centres participated in this study. Health centres were allocated to intervention and control arms using a matched-pair randomization technique. An in-service nutrition education and counselling package, including training for ANC providers, supportive supervision and provision of modules, pamphlets and job aids, was provided for health centres assigned to the intervention arm. Observation checklists were used to assess the counselling skills of health-care providers. We used mixed-effect linear regression to evaluate the impact of the intervention. Significantly more health-care providers in the intervention arm informed pregnant women about the need to have one additional meal (Difference in proportion [DP] 49.17% vs −0.84%; DID 50.0%), about minimum required dietary diversity (DP 72.5% vs −2.5%; DID 75.0%) and about gestational weight gain (DP 68.33% vs −8.33%; DID 76.6%). Furthermore, providers improved in identifying key difficulties that pregnant women face (DP 28.34% vs −2.5%; DID 30.8%), and in recommending simple achievable actions on nutrition during pregnancy (DP 20.8% vs −10.9%; DID 31.6%). The intervention did not have statistically significant effects on how providers informed women about early initiation of breastfeeding (DP 6.67% vs 9.17%; DID −2.5%). The comprehensive in-service nutrition education and counselling package improved how ANC providers engaged with pregnant women and delivered nutrition messages during ANC consultations. This trial was registered in the Pan African Clinical Trial (PACTR registry, PACTR20170900 2477373; Date issued 21 September 2017).
Mild stimulation should be mandatory for oocyte donation
Authors: Pennings Guido
Published: August 2020

The increasing commercialization of oocyte donation is a source of concern. This evolution is expressed in the fact that oocyte donors’ interests are not a priority. For decades now, people mention that oocyte donation holds serious health risks for donors, as if this is an unavoidable given. However, most of the harm is caused by high hormonal stimulation. The risk/benefit balance of high stimulation compared to the risk/benefit balance of mild stimulation does not justify causing greater harm to donors, especially given the fact that donors submit to the procedure without any medical benefit for themselves and to help others.
Prediction of square mesh panel and codend size selectivity of blue whiting based on fish morphology
Authors: Cuende Elsa , Arregi Luis , Herrmann Bent , Sistiaga Manu , Aboitiz Xabier
Published: August 2020

Square mesh panels (SMPs) are selective devices used extensively to supplement codend size selectivity in trawl fisheries. Therefore, predictions of the effect of mesh size in both SMPs and codends on size selectivity are valuable. Here, we established a framework to predict the size selection of blue whiting through different SMPs and diamond mesh codends based on the morphological characteristics of this species. We hypothesized that size selection for an SMP is determined by different fish contact angles, whereas different mesh opening angles determine size selection for the codend. Based on these hypotheses, we first developed a model that enabled us to predict which sizes of blue whiting are able to pass through meshes of different sizes and shapes. We then tested whether the selectivity for blue whiting of the SMP, the codend, and the combination of both could be explained by the models. Finally, we predicted the size selectivity of multiple combinations of SMPs and diamond mesh codends. The method presented here can potentially be applied to make predictions for species other than blue whiting.
Preempting the Entry of Near Perfect Substitutes
Authors: Lipatov Vilen , Neven Damien , Siotis Georges
Published: August 2020

When firms compete on price and quality-enhancing promotion in a market for differentiated products, entry of a nearly perfect substitute to one of such products, for example, a generic version of a pharmaceutical drug, intensifies price competition but softens quality competition. We show that consumers are likely to gain from entry when quality is relatively unimportant for them, when business stealing generated by promotion is substantial, and when products are poor substitutes. We also show that entry may be more attractive for consumers in less concentrated markets, as a smaller number of firms and asymmetric market shares may be associated with higher quality.
Anastomosis of dual renal transplant veins
Authors: Hoff Mekhola , Leighton Philippa , Hosgood Sarah A , Nicholson Michael L
Published: August 2020

As there is usually considerable overlap in the renal venous drainage, it is often possible to ligate supernumerary transplant renal veins in order to simplify the implantation procedure. Nonetheless, decisions about whether to implant multiple veins can be difficult and are usually made subjectively. Here, we describe the use of intraoperative Doppler ultrasound as an adjunct to decision-making when there are two renal veins and a novel technique for the sequential anastomosis of dual veins. The kidney was reperfused after anastomosis of the main renal vein with the second vein clamped. On-table Doppler ultrasound demonstrated reversed flow in diastole indicating that the second renal vein also needed to be anastomosed. By clamping the external iliac vein inferior to the first venous anastomosis it was possible to complete the lower polar renal vein anastomosis to the external iliac vein without interrupting the perfusion of the kidney.
The KBC void and Hubble tension contradict ΛCDM on a Gpc scale − Milgromian dynamics as a possible solution
Authors: Haslbauer Moritz , Banik Indranil , Kroupa Pavel
Published: August 2020

The KBC void is a local underdensity with the observed relative density contrast δ ≡ 1 − ρ/ρ0 = 0.46 ± 0.06 between 40 and 300 Mpc around the Local Group. If mass is conserved in the Universe, such a void could explain the 5.3σ Hubble tension. However, the MXXL simulation shows that the KBC void causes 6.04σ tension with standard cosmology (ΛCDM). Combined with the Hubble tension, ΛCDM is ruled out at 7.09σ confidence. Consequently, the density and velocity distribution on Gpc scales suggest a long-range modification to gravity. In this context, we consider a cosmological MOND model supplemented with $11 \, \rm {eV}/c^{2}$ sterile neutrinos. We explain why this νHDM model has a nearly standard expansion history, primordial abundances of light elements, and cosmic microwave background (CMB) anisotropies. In MOND, structure growth is self-regulated by external fields from surrounding structures. We constrain our model parameters with the KBC void density profile, the local Hubble and deceleration parameters derived jointly from supernovae at redshifts 0.023−0.15, time delays in strong lensing systems, and the Local Group velocity relative to the CMB. Our best-fitting model simultaneously explains these observables at the $1.14{{\ \rm per\ cent}}$ confidence level (2.53σ tension) if the void is embedded in a time-independent external field of ${0.055 \, a_{_0}}$. Thus, we show for the first time that the KBC void can naturally resolve the Hubble tension in Milgromian dynamics. Given the many successful a priori MOND predictions on galaxy scales that are difficult to reconcile with ΛCDM, Milgromian dynamics supplemented by $11 \, \rm {eV}/c^{2}$ sterile neutrinos may provide a more holistic explanation for astronomical observations across all scales.
Inevitable consequences of ion–neutral damping of intermediate MHD waves in Sun-like stars
Authors: Judge Philip G
Published: August 2020

In the context of the solar atmosphere, we re-examine the role of neutral and ionized species in dissipating the ordered energy of intermediate-mode MHD waves into heat. We solve conservation equations for the hydrodynamics and for hydrogen and helium ionization stages, along closed tubes of magnetic field. First, we examine the evolution of coronal plasma under conditions where coronal heating has abruptly ceased. We find that cool (<105K) structures are formed lasting for several hours. MHD waves of modest amplitude can heat the plasma through ion–neutral collisions with sufficient energy rates to support the plasma against gravity. Then we examine a calculation starting from a cooler atmosphere. The calculation shows that warm (>104) K long (> several Mm) tubes of plasma arise by the same mechanism. We speculate on the relevance of these solutions to observe properties of the Sun and similar stars whose atmospheres are permeated with emerging magnetic fields and stirred by convection. Perhaps this elementary process might help to explain the presence of ‘cool loops’ in the solar transition region and the production of broad components of transition region lines. The production of ionized hydrogen from such a simple and perhaps inevitable mechanism may be an important step towards finding the more complex mechanisms needed to generate coronae with temperatures in excess of 106K, independent of a star’s metallicity.
The effects of resolution on black hole accretion simulations of jets
Authors: White Christopher J , Chrystal Fiona
Published: August 2020

We perform three general-relativistic magnetohydrodynamic simulations of black hole accretion designed to test how sensitive results are to grid resolution in the jet region. The cases differ only in numerics, modelling the same physical scenario of a radiatively inefficient, geometrically thick, magnetically arrested flow on to a rapidly spinning black hole. Properties inferred with the coarsest grid generally agree with those found with higher resolutions, including total jet power and its decomposition into different forms, velocity structure, non-axisymmetric structure, and the appearance of resolved millimetre images. Some measures of variability and magnetization are sensitive to resolution. We conclude that most results obtained by limiting resolution near the jet for computational expediency should still be reliable, at least in so far as they would not be improved with a finer grid.
Probing shock acceleration in BL Lac jets through X-ray polarimetry: the time-dependent view
Authors: Tavecchio F , Landoni M , Sironi L , Coppi P
Published: August 2020

Polarimetric measurements, especially if extended at high energy, are expected to provide important insights into the mechanisms underlying the acceleration of relativistic particles in jets. In a previous work, we have shown that the polarization of the synchrotron X-ray emission produced by highly energetic electrons accelerated by a mildly relativistic shock carries essential imprints of the geometry and the structure of the magnetic fields in the downstream region. Here, we present the extension of our analysis to the non-stationary case, especially suitable to model the highly variable emission of high-energy emitting BL Lacs. We anticipate a large ($\Pi \approx 40{{\ \rm per\ cent}}$), almost time-independent degree of polarization in the hard/medium X-ray band, a prediction soon testable with the upcoming mission IXPE. The situation in other bands, in particular in the optical, is more complex. A monotonic decrease of the optical degree of polarization is observed during the development of a flare. At later stages, Π reaches zero and then it starts to increase, recovering large values at late times. The instant at which Π = 0 is marked by a rotation of the polarization angle by 90°. However, at optical frequencies, it is likely that more than one region contribute to the observed emission, potentially making it difficult to detect the predicted behaviour.
Exclusive E-Cigarette Users Report Lower Levels of Respiratory Symptoms Relative to Dual E-Cigarette and Cigarette Users
Authors: Cassidy Rachel N , Tidey Jennifer W , Colby Suzanne M
Published: August 2020

Introduction

Exclusive e-cigarette use has been shown to be associated with reduced levels of respiratory symptoms relative to smoking combustible cigarettes; this association has been less frequently studied in smokers using advanced-generation e-cigarette devices. Advanced-generation devices generate denser vapor than either early generation or pod-style devices, and engender longer inhalations; these vaping topography patterns may contribute to respiratory symptoms.

Methods

In a single-session, cross-sectional study of exclusive e-cigarette users (N = 59) and dual users of e-cigarettes and cigarettes (N = 54), participants completed questionnaires, including the American Thoracic Society Questionnaire (ATSQ) and were videotaped vaping their own device in the lab for 1 hour. Using a hierarchical regression method, we examined whether topography variables, level of nicotine concentration used in their e-cigarette device in the past month, e-cigarette dependence, amount of e-cigarette use in the past month, and smoking status (any smoking in the last month vs. none) predicted ATSQ score severity.

Results

There was a significant mean difference in ATSQ score across smoking status, with greater ATSQ scores for vapers who also smoked cigarettes (19.0, SD = 6.7) than for exclusive vapers (13.4, SD = 5.3). In the final model, of the predictors of interest, only cigarette smoking status predicted significantly greater ATSQ scores (overall F = 2.51, p = .006; R2 = .26; smoking status β = 0.39, p < .0001).

Conclusions

Findings suggest that differences in respiratory symptoms between dual and exclusive e-cigarette users appear to be attributable to combustible cigarette smoking, rather than more intense or frequent e-cigarette use across groups.

Implications

In this comparison of exclusive advanced-generation vape device users (N = 59) versus dual users of these devices and combustible cigarettes (N = 54), we set out to determine the extent to which smoking status and e-cigarette use variables predicted self-reported respiratory symptom severity. We found that dual users showed greater respiratory symptom severity (ATSQ scores) than exclusive vapers. Despite examining vaping topography and other variables, smoking status and race were the only significant predictor of respiratory symptoms. We conclude that combustible cigarette use, not individual vaping topography, likely accounts for differences in respiratory symptoms between dual users and exclusive vapers.
Smokers’ Exposure to Perceived Modified Risk Claims for E-Cigarettes, Snus, and Smokeless Tobacco in the United States
Authors: Wackowski Olivia A , O’Connor Richard J , Pearson Jennifer L
Published: August 2020

Introduction

Based on arguments for harm reduction and health benefits, tobacco companies in the United States can apply for regulatory authorization to make “modified risk tobacco product” (MRTP) marketing claims. The impact of future MRTP claims may depend on whether they are noticed, believed, and lead to smokers switching products. This study provides baseline data about smokers’ exposure to perceived MRTP claims ahead of any MRTP authorizations.

Aims and Methods

We analyzed measures from Wave 3 of the US-based Population Assessment of Tobacco and Health (PATH) study which asked smokers to indicate if they had seen any e-cigarettes, snus, or other smokeless tobacco (SLT) products that claim to be “less harmful” in the past 12 months, and their likelihood of using products with these claims in the next 30 days.

Results

Significantly fewer smokers noted having seen snus (5.1%) or other SLT (5.6%) with “less harmful” claims compared with e-cigarettes (29.1%). For each product, the prevalence of MRTP claim exposure was higher among smokers who perceived the product to be less harmful than smoking, who currently used the product, and who had higher rates of tobacco advertising exposure at the point of sale. Among smokers who noticed products with “less harmful” claims, about one-quarter said they would use them in the future (24%–27%).

Conclusions

Ahead of any Food & Drug Administration (FDA) authorization for MRTP claims, some smokers already perceive exposure to “less harmful” claims for e-cigarettes, but few do for SLT. MRTP claims may motivate some smokers to use these products.

Implications

This study provides new baseline data about smokers’ perceived exposure to MRTP claims in the United States ahead of any regulatory claim authorization. Using data from Wave 3 of the US PATH study, we found that some smokers already perceive exposure to “less harmful” claims for e-cigarettes (29%), but few do for SLT (5%–6%). Among smokers who noticed products with “less harmful” claims, about one-quarter said they would use them in the future (24%–27%), suggesting MRTP claims may motivate some smokers to use products described as “less harmful.”