bluuebunny/crossref_metadata_2025 huggingface dataset:
Casimir–Polder interaction of neutrons with metal or dielectric surfaces
Authors: Gebhart Valentin , Klatt Juliane , Cronenberg Gunther , Filter Hanno , Buhmann Stefan Yoshi
Published: June 2021

We predict a repulsive Casimir–Polder-type dispersion interaction between a single neutron and a metal or dielectric surface. We consider a scenario where a single neutron is subject to an external magnetic field. Due to its intrinsic magnetic moment, the neutron then forms a magnetisable two-level system which can exchange virtual photons with a nearby surface. The resulting dispersion interaction between a purely magnetic object (neutron) and a purely electric one (surface) is found to be repulsive, in contrast to the typical attractive interaction between electric objects. Its magnitude is considerably smaller than the standard atom–surface Casimir–Polder force due to the magnetic nature of the interaction and the smallness of the electron-to-neutron mass ratio. Nevertheless, we show that it can be comparable to the gravitational potential of the same surface and should be taken into consideration in future neutron interference experiments.
Few-body correlations in two-dimensional Bose and Fermi ultracold mixtures
Authors: Bougas G , Mistakidis S I , Giannakeas P , Schmelcher P
Published: June 2021

Few-body correlations emerging in two-dimensional harmonically trapped mixtures, are comprehensively investigated. The presence of the trap leads to the formation of atom-dimer and trap states, in addition to trimers. The Tan’s contacts of these eigenstates are studied for varying interspecies scattering lengths and mass ratio, while corresponding analytical insights are provided within the adiabatic hyperspherical formalism. The two- and three-body correlations of trimer states are substantially enhanced compared to the other eigenstates. The two-body contact of the atom-dimer and trap states features an upper bound regardless of the statistics, treated semi-classically and having an analytical prediction in the limit of large scattering lengths. Such an upper bound is absent in the three-body contact. Interestingly, by tuning the interspecies scattering length the contacts oscillate as the atom-dimer and trap states change character through the existent avoided-crossings in the energy spectra. For thermal gases, a gradual suppression of the involved two- and three-body correlations is evinced manifesting the impact of thermal effects. Moreover, spatial configurations of the distinct eigenstates ranging from localized structures to angular anisotropic patterns are captured. Our results provide valuable insights into the inherent correlation mechanisms of few-body mixtures which can be implemented in recent ultracold atom experiments and will be especially useful for probing the crossover from few- to many-atom systems.
Gamma-ray and synchrotron radiation from dark matter annihilations in ultra-faint dwarf galaxies
Authors: Bhattacharjee Pooja , Choudhury Debajyoti , Das Kasinath , Kumar Ghosh Dilip , Majumdar Pratik
Published: June 2021

The very large (100–1000) mass-to-light ratio applicable to the
ultra-faint dwarf galaxies (UFDs) implies a high concentration of dark
matter, thus rendering them ideal theatres for indirect signatures of
dark matter. In this paper, we consider 14 recently discovered UFDs
and study the electromagnetic radiation emanating from them over a
wide range, from gamma ray down to radio frequencies. We analyze the
Fermi-LAT data on high energy gamma rays and radio fluxes at the GMRT
and VLA to obtain upper limits on annihilation cross section
⟨σ v⟩ in a model independent way. We further
discuss the sensitivity of the Square Kilometer Array radio telescope
in probing the synchrotron radiation from the aforementioned UFDs. We
also investigate the dependences of the said upper limits on the
uncertainties in the determination of various astrophysical
parameters.
Corrigendum: The Remote Observatories of the Southeastern Association for Research in Astronomy (SARA)
Authors: Keel William C. , Oswalt Terry , Mack Peter , Henson Gary , Hillwig Todd , Batcheldor Daniel , Berrington Robert , De Pree Chris , Hartmann Dieter , Leake Martha , Licandro Javier , Murphy Brian , Webb James , Wood Matt A.
Published: June 2021

Bill Gray of Project Pluto brought to our attention an error of 0.03° in the listed latitude of our Kitt Peak telescope. While correcting the table where this occurred, we also take the opportunity to update the instrument properties and weather statistics of our remote telescopes.
Mechanism of microweld formation and breakage during Cu–Cu wire bonding investigated by molecular dynamics simulation
Authors: Gu Beikang , Shen Shengnan , Li Hui
Published: June 2021

Currently, wire bonding is the most popular first-level interconnection technology used between the die and package terminals, but even with its long-term and excessive usage, the mechanism of wire bonding has not been completely evaluated. Therefore, fundamental research is still needed. In this study, the mechanism of microweld formation and breakage during Cu–Cu wire bonding was investigated by using molecular dynamics simulation. The contact model for the nanoindentation process between the wire and substrate was developed to simulate the contact process of the Cu wire and Cu substrate. Elastic contact and plastic instability were investigated through the loading and unloading processes. Moreover,the evolution of the indentation morphology and distributions of the atomic stress were also investigated. It was shown that the loading and unloading curves do not coincide, and the unloading curve exhibited hysteresis. For the substrate, in the loading process, the main force changed from attractive to repulsive. The maximum von Mises stress increased and shifted from the center toward the edge of the contact area. During the unloading process, the main force changed from repulsive to attractive. The Mises stress reduced first and then increased. Stress concentration occurs around dislocations inthe middle area of the Cu wire.
Impact of STI indium implantation on reliability of gate oxide
Authors: Chen Xiao-Liang , Chen Tian , Sun Wei-Feng , Qian Zhong-Jian , Li Yu-Dai , Jin Xing-Cheng
Published: June 2021

The impacts of shallow trench isolation (STI) indium implantation on gate oxide and device characteristics are studied in this work. The stress modulation effect is confirmed in this research work. An enhanced gate oxide oxidation rate is observed due to the enhanced tensile stress, and the thickness gap is around 5%. Wafers with and without STI indium implantation are manufactured using the 150-nm silicon on insulator (SOI) process. The ramped voltage stress and time to breakdown capability of the gate oxide are researched. No early failure is observed for both wafers the first time the voltage is ramped up. However, a time dependent dielectric breakdown (TDDB) test shows more obvious evidence that the gate oxide quality is weakened by the STI indium implantation. Meanwhile, the device characteristics are compared, and the difference between two devices is consistent with the equivalent oxide thickness (EOT) gap.
Mode splitting and multiple-wavelength managements of surface plasmon polaritons in coupled cavities
Authors: Fu Ping-Bo , Chen Yue-Gang
Published: June 2021

Resonance cavity is a basic element in optics, which has wide applications in optical devices. Coupled cavities (CCs) designed in metal-insulator-metal (MIM) bus waveguide are investigated through the finite difference time domain method and coupled-mode theory. In the CCs, the resonant modes of the surface plasmon polaritons (SPPs) split with the thickness decreasing of the middle baffle. Through the coupled-mode theory analysis, it is found that the phase differences introduced in opposite and positive couplings between two cavities lead to mode splitting. The resonant wavelength of positive coupling mode can be tuned in a large range (about 644 nm) through adjusting the coupling strength, which is quite different from the classical adjustment of the optical path in a single cavity. Based on the resonances of the CCs in the MIM waveguide, more compact devices can be designed to manipulate SPPs propagation. A device is designed to realize flexible multiple-wavelength SPPs routing. The coupling in CC structures can be applied to the design of easy-integrated laser cavities, filters, multiple-wavelength management devices in SPPs circuits, nanosensors, etc.
Low-cost wireless smart device design for radiation protection and nuclear security
Authors: Mbarndouka Taamté J. , Saïdou  , Bodo B. , Kountchou Noubé M. , Folifack Signing V.R. , Yakum-Ntaw Younui S. , Hamadou Yerima A. , Iamsumang C. , Massey C.
Published: June 2021

This article presents the realization and implementation of
a low-cost intelligent electronic device, which detects the ambient
dose rate of Gamma and Beta ionizing radiation in
real-time. Developed according to the principle of nuclear analog
signal processing, the device uses a Geiger-Müller tube detector,
in which the electronic circuit has been readjusted to produce the
standard radiation protection signal (a slow positive logic
pulses). It also consists of low-cost components such as the
Atmega328P microcontroller board and XBee wireless modules for
environmental radiation and nuclear security monitoring. The
proposed device has several advantages, namely low energy
consumption, low-cost, easily deployable in the field (in-situ),
adapted for real-time measurements and data transmission to a remote
personal computer (PC). After calibration using Cesium (137Cs),
a comparative analysis of the data obtained from the proposed
dosimeter was carried out with those of an in-situ gamma
spectrometry chain (reference method) previously used at the same
place and under the same conditions. This analysis gave an
acceptable mean value of 64.30 nGy/h, of the proposed device,
compared to that of the gamma spectrometer, which is 50.67 nGy/h. The
prototype thus developed is simple, precise, and made for radiation
protection.
Exploring carbon footprint reduction pathways through urban lifestyle changes: a practical approach applied to Japanese cities
Authors: Koide Ryu , Kojima Satoshi , Nansai Keisuke , Lettenmeier Michael , Asakawa Kenji , Liu Chen , Murakami Shinsuke
Published: June 2021

Cities and urban consumers play a central role in the transition to a decarbonized society. Building on existing studies that identify the significant contributions of lifestyle changes, this study proposes a practical methodology for modeling and exploring city-specific carbon footprint reduction pathways through lifestyle changes to decarbonization. It uses an input–output approach with mixed-unit consumption data and the concept of adoption rates, which is applicable to multiple cities with widely available subnational household consumption data. This paper illustrates the use of this methodology by exploring the consumption-based mitigation pathways of 52 Japanese cities with 65 lifestyle change options covering mobility, housing, food, consumer goods, and leisure domains. The results revealed that city-specific impacts of a variety of lifestyle change options can differ by as much as a factor of five among cities, even in the urban context within the same country. Due to this city-level heterogeneity, the priority options of decarbonized lifestyles, such as among shared mobility, low-carbon diets, and longevity of consumer goods, have shifted between cities. The analysis suggests that ambitious urban lifestyle changes can potentially reduce their carbon footprints to meet the 1.5 °C target. However, due to the overlaps of mitigation potentials between multiple lifestyle change options, the necessary levels of adoption and coverage are extensive (i.e. adoption rates of 0.6–0.9). Importantly, adopting lifestyle changes with an efficiency strategy (e.g. the introduction of end-use technologies) or sufficiency strategy (e.g. behavioral changes in consumption amounts and modes) alone is not enough; the only way to succeed is through the combination of both strategies. This paper calls for a target-based exploration and identification of city-specific priorities of lifestyle change options to facilitate consumption-oriented mitigation policies and stakeholder actions to address the climate impacts of urban consumption.
Intensive field sampling increases the known extent of carbon-rich Amazonian peatland pole forests
Authors: Honorio Coronado Eurídice N , Hastie Adam , Reyna José , Flores Gerardo , Grández Julio , Lähteenoja Outi , Draper Frederick C , Åkesson Christine M , Baker Timothy R , Bhomia Rupesh K , Cole Lydia E S , Dávila Nállarett , Del Águila Jhon , Del Águila Margarita , Del Castillo Torres Dennis , Lawson Ian T , Martín Brañas Manuel , Mitchard Ed T A , Monteagudo Abel , Phillips Oliver L , Ramírez Eliseo , Ríos Marcos , Ríos Sandra , Rodriguez Lily , Roucoux Katherine H , Tagle Casapia Ximena , Vasquez Rodolfo , Wheeler Charlotte E , Montoya Mariana
Published: June 2021

Peatland pole forest is the most carbon-dense ecosystem in Amazonia, but its spatial distribution and species composition are poorly known. To address this knowledge gap, we quantified variation in the floristic composition, peat thickness, and the amount of carbon stored above and below ground of 102 forest plots and 53 transects in northern Peruvian Amazonia. This large dataset includes 571 ground reference points of peat thickness measurements across six ecosystem types. These field data were also used to generate a new land-cover classification based on multiple satellite products using a random forest classification. Peatland pole forests are floristically distinctive and dominated by thin-stemmed woody species such asPachira nitida(Malvaceae),Platycarpum loretense(Rubiaceae), andHevea guianensis(Euphorbiaceae). In contrast, palm swamps and open peatlands are dominated byMauritia flexuosa(Arecaceae). Peatland pole forests have high peat thickness (274 ± 22 cm, mean ± 95% CI,n= 184) similar to open peatlands (282 ± 46 cm,n= 46), but greater than palm swamps (161 ± 17 cm,n= 220) and seasonally-flooded forest, terra firme, and white-sand forest where peat is rare or absent. As a result, peatland pole forest has exceptional carbon density (1,133 ± 93 Mg C ha−1). The new sites expand the known distribution of peatland pole forest by 61% within the Pastaza-Marañón Foreland basin, mainly alongside the Tigre river, to cover a total of 7540 km2in northern Peruvian Amazonia. However, only 15% of the pole forest area is within a protected area, whilst an additional 26% lies within indigenous territories. The current low levels of protection and forest degradation but high threat from road paving projects makes the Tigre river basin a priority for conservation. The long-term conservation of peatland pole forests has the potential to make a large contribution towards international commitments to mitigate climate change.
Retraction: Social and Islamic diffusion in the Nordic countries with the example of Sweden by year 2050 (IOP Conf. Ser.: Earth Environ. Sci.
302 012071)
Authors: Yu Eidemiller K , Samylovskaya E A , A Kudryavtseva R-E , Alakshin A E
Published: June 2021

IOP Publishing Limited ("IOPP") is retracting this paper following an investigation which resulted from a reader complaint. The paper makes a number of unsubstantiated claims and, in the opinion of IOPP, lacks scientific rigour, clarity and objectivity. Although the paper was subject to peer review via the conference organisers, unfortunately these issues were not identified on this occasion. IOPP also has concerns regarding the discriminatory tone and sentiment of the paper, which are not appropriate in a scientific journal.

IOPP expresses its thanks to the readers and independent advisors who have shared their thoughts regarding this paper during the course of the investigation.

Retraction published: 24 June 2021
Modeling of the stress-strain state of reinforced concrete beams under prolonged load action
Authors: Holovata Z , Neutov S , Surianinov M
Published: June 2021

The paper considers the use of a layered deformation model of the stress-strain state of reinforced concrete beams experiencing transverse bending taking into account the long-term action of the load. The results of experimental studies of twelve beams made of concrete of three classes for short-term and long-term acting load are given. It has been established that long-term strength of inclined cross-sections follows the general laws of deformation and fracture of reinforced concrete. Comparison of calculation results of the proposed deformation model with experimental data has shown their satisfactory convergence. A tendency of some increase (within 10… 15%) in the long-term strength of the reinforced concrete elements under study in the inclined sections has been established experimentally.
Experimental studies of road slabs
Authors: Surianinov M , Neutov S , Korneieva I , Kirichenko D
Published: June 2021

The results of experimental studies of bearing capacity and cracking resistance of road slab models made of steel-fiber concrete according to the span loading scheme are presented. The bearing capacity of the models has been fixed at 27.96 kN, which is 2 times higher than the load corresponding to the beginning of cracking (14.8 kN). At the moment of bearing capacity loss, the height of compressed zone was 1 cm, which is one third of its original size. The relative strains before the first crack appeared were 0.1175×10-4 and 0.235×10-4 in the compressed and stretched zones, respectively, and similar limiting relative strains reached values of 3.715×10-4 and 9.235×10-4. The maximum crack opening width was substantially less than in the same tests of the slabs without dispersion reinforcement and was 0.3 mm, which is explained by the more ductile properties of steel fiber concrete, which prevent crack opening. The final deflection in the middle of the plate model span was 10.4 mm, which is 5.5 times greater than the deflection before cracking began (1.9 mm).
Geometry and graphics of the fractal expansion of a square and its applications
Authors: Tkach D , Sopilniak A , Yarova T , Sereda S , Kistol A
Published: June 2021

Geometry of the fractal expansion of simple geometric shapes, in particular the square, 5-celled cross and swastikas, is a new section of fractal geometry that correctly and clearly describes the dynamics of natural processes of growth and development of animate and inanimate cellular structures, since the iterative processes of their fractal expansion are mutually complementary and inextricably interconnected. The theoretical part of this paper requires further research, and the practical one needs for the design and engineering, and technological development of a solution to the problem for building roads with the fractal-synergetic pavement as an alternative to asphalt.
Crack formation and measurement in concrete with carbon fiber-reinforced composites under bending test
Authors: Vashpanov Yuriy , Park Jong Gun , Podousova Tatyana , Heo Gwang Hee , Son Jung Young
Published: June 2021

The certified test equipment of the MTDI Inc. Materials Testing System under bending test was using for cracking in concrete with carbon fiber-reinforced composites. The concrete samples included microfibers 6 and 12 mm long with a total volume fraction of fibers from 0.5 to 2.0%. To record the results of the experiment, a high-speed video camera was used, since with an increase in the value of the load, cracking and then destruction of the sample can occur at any moment, which is unpredictable when using different samples. This significantly increases the accuracy of determining the moment of crack formation and describing the geometric dimensions of cracks depending on the load. Optical non-contact methods of the measurements and image processing is used for determining the geometric dimensions of cracks in specimen. For concrete containing carbon fibers 6 mm long, with an increase in load and volume fractions ν cracking occurs at loads that are 1.67 times lower than in specimens with 12 mm filaments. Concretes with 12 mm long carbon fibers had a higher time for crack formations (the load increased linearly with time on Bending jig of the Materials Testing System), which slightly increases by 1.13 times with increasing parameter ν from 0.5 to 2.0%. Cracks in concrete in both cases are observed at practically the same load magnitudes at values of ν =2%.
Models of co-evolution of structural elements of building composites
Authors: Vyrovoy V , Sukhanov V , Ielkin A , Sukhanova S
Published: June 2021

It is shown that construction material changes its properties as a result of operational loads action. There are situations when construction leaves its working state with satisfactory material characteristics. This is due to the process of formation and development of cracks as structural elements. The article proposes to analyze history of the development process, which makes it possible to study mechanisms of its flow and to determine factors of process control. The analysis of the studies carried out on the effect of prescriptional and technological factors on the properties of materials and products, the phenomena of self-organization and the role of cracks in materials and products showed that the emergence of critical events cannot be foreseen when assessing properties accepted by averaged characteristics. The construction is considered to be a complex self-organizing system. This determined the work aim: to justify the choice of dynamic models, allowing to determine the structure elements, interaction of which ensures functional state of the structure. The qualitative method of verbal description of the structure of systems with the use of cognitive approaches was laid in basis of adopted methodology. Conservative, metastable and active elements are distinguished in the construction-system. It is emphasized that the active history of the system is determined by active elements, to which cracks refer to. Cracks are considered as some necessary structural elements, present at all scale levels. It is shown that the formation of cracks-systems, treated as parasitic systems, terminates the end of construction-system development and the beginning of parasite system development. Completion of crack-system life cycle removes the construction-system from its working state. To get constructions with a given set of structural elements, a creative community of materials and designers is needed, which will create a common terminology dictionary for both specializations.
A Comprehensive Overview of Technologies for Species and Habitat Monitoring and Conservation
Authors: Lahoz-Monfort José J , Magrath Michael J L
Published: June 2021

The range of technologies currently used in biodiversity conservation is staggering, with innovative uses often adopted from other disciplines and being trialed in the field. We provide the first comprehensive overview of the current (2020) landscape of conservation technology, encompassing technologies for monitoring wildlife and habitats, as well as for on-the-ground conservation management (e.g., fighting illegal activities). We cover both established technologies (routinely deployed in conservation, backed by substantial field experience and scientific literature) and novel technologies or technology applications (typically at trial stage, only recently used in conservation), providing examples of conservation applications for both types. We describe technologies that deploy sensors that are fixed or portable, attached to vehicles (terrestrial, aquatic, or airborne) or to animals (biologging), complemented with a section on wildlife tracking. The last two sections cover actuators and computing (including web platforms, algorithms, and artificial intelligence).
Optimization of sugar production from Durian seeds via alkaline hydrolysis for second-generation bioethanol production
Authors: Chriswardana Theofany Harley , Mulyaningsih Yheni , Mulyaningsih Yhana , Bahar Aditiya Harjon , Riayatsyah Teuku Meurah Indra
Published: June 2021

As one way to eliminate the issues found in the preceding generation, feedstock exploration in second-generation bioethanol production remains an issue, especially for a tropical country such as Indonesia. From exotic fruit by-products, durian holds a promising perspective that rests on its abundance, superb carbohydrate content and limited usage until now. This work presents the first-ever utilization of durian seeds for sugar production under optimized conditions through alkaline hydrolysis. A simple form of sugar was extracted by varying four parameters, namely substrate loading, NaOH concentration, hydrolysis time and hydrolysis temperature. Response surface methodology based on the Box-Behnken design was employed to outline the most optimum parameter values. Analysis of variance revealed that the quadratic model fit the data appropriately with the order of significance as substrate loading > hydrolysis time > NaOH concentration > hydrolysis temperature. The optimized conditions for reducing sugar yield, as high as 2.140 g/L, corresponded to <50 g/L substrate loading, 0.522 M NaOH, 60 minutes of hydrolysis time and 80oC hydrolysis temperature. The possible ethanol content of 1.094 g/L was also expected under optimized conditions, demonstrating great potential in second-generation bioethanol production.

Second-generation bioethanol production from a non-edible feedstock (durian seeds) is optimized by varying key parameters in the alkaline hydrolysis process, showing high yields of fermentable sugars.
Comparison of the Immunogenicity of Cell Culture-Based and Recombinant Quadrivalent Influenza Vaccines to Conventional Egg-Based Quadrivalent Influenza Vaccines Among Healthcare Personnel Aged 18–64 Years: A Randomized Open-Label Trial
Authors: Dawood Fatimah S , Naleway Allison L , Flannery Brendan , Levine Min Z , Murthy Kempapura , Sambhara Suryaprakash , Gangappa Shivaprakash , Edwards Laura , Ball Sarah , Grant Lauren , Belongia Edward , Bounds Kelsey , Cao Weiping , Gross F Liaini , Groom Holly , Fry Alicia M , Rentz Hunt Danielle , Jeddy Zuha , Mishina Margarita , Kim Sara S , Wesley Meredith G , Spencer Sarah , Thompson Mark G , Gaglani Manjusha
Published: June 2021

Background

RIV4 and cell-culture based inactivated influenza vaccine (ccIIV4) have not been compared to egg-based IIV4 in healthcare personnel, a population with frequent influenza vaccination that may blunt vaccine immune responses over time. We conducted a randomized trial among healthcare personnel (HCP) aged 18–64 years to compare humoral immune responses to ccIIV4 and RIV4 to IIV4.

Methods

During the 2018–2019 season, participants were randomized to receive ccIIV4, RIV4, or IIV4 and had serum samples collected prevaccination, 1 and 6 months postvaccination. Serum samples were tested by hemagglutination inhibition (HI) for influenza A/H1N1, B/Yamagata, and B/Victoria and microneutralization (MN) for A/H3N2 against cell-grown vaccine reference viruses. Primary outcomes at 1 month were seroconversion rate (SCR), geometric mean titers (GMT), GMT ratio, and mean fold rise (MFR) in the intention-to-treat population.

Results

In total, 727 participants were included (283 ccIIV4, 202 RIV4, and 242 IIV4). At 1 month, responses to ccIIV4 were similar to IIV4 by SCR, GMT, GMT ratio, and MFR. RIV4 induced higher SCRs, GMTs, and MFRs than IIV4 against A/H1N1, A/H3N2, and B/Yamagata. The GMT ratio of RIV4 to egg-based vaccines was 1.5 (95% confidence interval [CI] 1.2–1.9) for A/H1N1, 3.0 (95% CI: 2.4–3.7) for A/H3N2, 1.1 (95% CI: .9–1.4) for B/Yamagata, and 1.1 (95% CI: .9–1.3) for B/Victoria. At 6 months, ccIIV4 recipients had similar GMTs to IIV4, whereas RIV4 recipients had higher GMTs against A/H3N2 and B/Yamagata.

Conclusions

RIV4 resulted in improved antibody responses by HI and MN compared to egg-based vaccines against 3 of 4 cell-grown vaccine strains 1 month postvaccination, suggesting a possible additional benefit from RIV4.

Clinical Trials Registration

NCT03722589.
The Effect of Buprenorphine on Human Immunodeficiency Virus Viral Suppression
Authors: Kim Jongyeon , Lesko Catherine R , Fojo Anthony T , Keruly Jeanne C , Moore Richard D , Chander Geetanjali , Lau Bryan
Published: June 2021

Background

Opioid use is prevalent among people living with human immunodeficiency virus (HIV; PLWH) and adversely affects HIV outcomes. We assessed the effect of buprenorphine (BUP) initiation on subsequent HIV viral loads.

Methods

We identified PLWH from the Johns Hopkins HIV Clinical Cohort who initiated BUP between 2002 and 2017. Poisson regression with robust variance was used to estimate the prevalence of viral suppression (<200 copies/mL) before and after BUP initiation. We matched individuals who initiated BUP with controls based on viral load measurement dates and used prior event rate ratio (PERR) methods to estimate the effect of BUP initiation on viral suppression. PERR methods account for unmeasured confounders.

Results

We identified 279 PLWH who initiated BUP. After BUP initiation, PLWH were more likely to be virally suppressed (prevalence ratio [PR], 1.19; 95% confidence interval [CI], 1.03–1.37). After matching PLWH who initiated BUP to controls and accounting for measured and unmeasured confounders, BUP initiation increased viral suppression for both those on antiretroviral therapy (ART) at baseline (PERR PR, 1.08; 95% CI, 1.00–1.18) and those not on ART at baseline (PR, 1.31; 95% CI, 1.10–1.61).

Conclusions

Our results indicate that the initiation of BUP results in an increase in the probability of being virally suppressed after accounting for both measured and unmeasured confounders. Persons with opioid use disorder should initiate BUP to not only treat substance use but also to increase viral suppression allowing for treatment as prevention.
Hypernatraemia and low eGFR at hospitalization in COVID-19 patients: a deadly combination
Authors: Longhitano Elisa , Nardi Chiara , Calabrese Vincenzo , Messina Roberta , Mazzeo Giuliana , Venanzi Rullo Emmanuele , Ceccarelli Manuela , Chatrenet Antoine , Saulnier Patrick , Torreggiani Massimo , Nunnari Giuseppe , Piccoli Giorgina Barbara , Santoro Domenico
Published: June 2021

Background

The coronavirus disease 2019 (COVID-19) pandemic has had a profound impact on the general population and the burden of pre-existing comorbidities has heavily affected the outcome of the infection. Hyponatraemia has been frequently described. Conversely, hypernatraemia has rarely been described in COVID-19.

Methods

The studied cohort encompasses all COVID-19 patients consecutively admitted to the Messina Hospital, Italy, during the first wave of the epidemic. Since healthcare structures were not overwhelmed at that time, indications for hospitalization were homogeneous throughout the study period. Serum sodium levels, kidney function [estimated glomerular filtration rate (eGFR)], demographic and clinical characteristics were recorded at admission. Correlation between mortality, sodium and eGFR was evaluated by survival curves and univariate and multivariate regression models.

Results

Baseline biochemical and clinical data at the time of admission were available for 115 COVID-19-confirmed patients. The median age at admission was 73 years (48% men), with a median Charlson Comorbidity Index of 4. A total of 23.5% of patients presented with a sodium level ≥146 mmol/L, while 7.8% had sodium <135 mmol/L. Hypernatraemic patients were older, with higher comorbidity. Age, hypernatraemia and reduced eGFR were associated with increased mortality in both univariate and multivariate regression models (P < 0.001). The combination of hypernatraemia and reduced renal function at admission had an odds ratio of 47.67 (95% confidence interval 10.08–225.43) of dying compared with patients with an eGFR ≥60 mL/min and sodium <145 mmol/L.

Conclusions

Our study suggests that the association between hypernatraemia and reduced eGFR at referral is a highly relevant prognostic marker for death during hospitalization. The role of this association should be further tested in larger, multicentre cohorts.
Poetry and Journalism Revisited: Toward an Affective Dimension of Journalism Culture
Authors: Parks Perry
Published: June 2021

This article seeks to reconcile disparate conceptions of thinking and feeling in journalism by foregrounding an affective dimension of news epistemology through the example of journalistic poetry. Drawing from Archibald MacLeish’s classic 20th-century lecture linking knowledge and the imagination, and locating Postema and Deuze’s continuum of journalism and the arts within Hanitzsch’s broader framework of journalism culture, I explore the generative spectrum in which certain kinds of journalism are best performed as poetry, and certain kinds of poetry are simply affective journalism by another name. The argument draws on historical, cultural, and literary scholarship to define the relationship between poetry and journalism, review historical uses of poetry in newspapers, show how poetry developed as a boundary object that “objective” news has defined itself against, and present four mini-case studies of poetry doing journalistic work in the 21st century.
The perspective of Canadian health care professionals on abortion service during the COVID-19 pandemic
Authors: Ennis Madeleine , Wahl Kate , Jeong Dahn , Knight Kira , Renner Regina , Munro Sarah , Dunn Sheila , Guilbert Edith , Norman Wendy V
Published: June 2021

Background

The COVID-19 pandemic and pandemic response created novel challenges for abortion services. Canada was uniquely positioned to transition to telemedicine because internationally common restrictions on abortion medication were removed before the pandemic.

Objective

We sought to characterize the experiences of abortion health care professionals in Canada during the COVID-19 pandemic and the impact of the pandemic response on abortion services.

Methods

We conducted a sequential mixed methods study between July 2020 and January 2021. We invited physicians, nurse practitioners and administrators to participate in a cross-sectional survey containing an open-ended question about the impact of the pandemic response on abortion care. We employed an inductive codebook thematic analysis, which informed the development of a second, primarily quantitative survey.

Results

Our initial survey had 307 respondents and our second had 78. Fifty-three percent were family physicians. Our first survey found respondents considered abortion access essential. We identified three key topicss: access to abortion care was often maintained despite pandemic-related challenges (e.g. difficulty obtaining tests, additional costs); change of practice to low-touch medication abortion care and provider perceptions of patient experience, including shifting demand, telemedicine acceptability and increased rural access. The second survey indicated uptake of telemedicine medication abortion among 89% of participants except in Quebec, where regulations meant procedures were nearly exclusively surgical. Restrictions did not delay care according to 76% of participants.

Conclusions

Canadian health care professionals report their facilities deemed abortion an essential service. Provinces and territories, except Quebec, described a robust pandemic transition to telemedicine to ensure access to services.

Podcast

An accompanying podcast is available in the Supplementary Data, in which the authors Dr Madeleine Ennis and Kate Wahl discuss their research on how family planning care and access to abortion services have changed during the COVID-19 pandemic.
Deaths, Disparities, and Cumulative (Dis)Advantage: How Social Inequities Produce an Impairment Paradox in Later Life
Authors: Jackson Heide , Engelman Michal
Published: June 2021

Background

Research on health across the life course consistently documents widening racial and socioeconomic disparities from childhood through adulthood, followed by stabilization or convergence in later life. This pattern appears to contradict expectations set by cumulative (dis)advantage (CAD) theory. Informed by the punctuated equilibrium perspective, we examine the relationship between midlife health and subsequent health change and mortality and consider the impact of earlier socioeconomic exposures on observed disparities.

Methods

Using the Health and Retirement Study, we characterize the functional impairment histories of a nationally representative sample of 8464 older adults between 1994 and 2016. We employ nonparametric and discrete outcome multinomial logistic regression to examine the competing risks of mortality, health change, and attrition.

Results

Exposures to disadvantages are associated with poorer functional health in midlife and mortality. However, a higher number of functional limitations in midlife is negatively associated with the accumulation of subsequent limitations for White men and women and for Black women. The impact of educational attainment, occupation, wealth, and marriage on later-life health differs across race and gender groups.

Conclusions

Observed stability or convergence in later-life functional health disparities is not a departure from the dynamics posited by CAD, but rather a result of the differential impact of racial and socioeconomic inequities on mortality and health at older ages. Higher exposure to disadvantages and a lower protective impact of advantageous exposures lead to higher mortality among Black Americans, a pattern which masks persistent health inequities later in life.
What Cut-Point in Gait Speed Best Discriminates Community-Dwelling Older Adults With Mobility Complaints From Those Without? A Pooled Analysis From the Sarcopenia Definitions and Outcomes Consortium
Authors: Cawthon Peggy M , Patel Sheena M , Kritchevsky Stephen B , Newman Anne B , Santanasto Adam , Kiel Douglas P , Travison Thomas G , Lane Nancy , Cummings Steven R , Orwoll Eric S , Duchowny Kate A , Kwok Timothy , Hirani Vasant , Schousboe John , Karlsson Magnus K , Mellström Dan , Ohlsson Claes , Ljunggren Östen , Xue Qian-Li , Shardell Michelle , Jordan Joanne M , Pencina Karol M , Fielding Roger A , Magaziner Jay , Correa-de-Araujo Rosaly , Bhasin Shalender , Manini Todd M
Published: June 2021

Background

Cut-points to define slow walking speed have largely been derived from expert opinion.

Methods

Study participants (13 589 men and 5043 women aged ≥65years) had walking speed (m/s) measured over 4–6 m (mean ± SD: 1.20 ± 0.27 m/s in men and 0.94 ± 0.24 m/s in women.) Mobility limitation was defined as any self-reported difficulty with walking approximately 1/4 mile (prevalence: 12.6% men, 26.4% women). Sex-stratified classification and regression tree (CART) models with 10-fold cross-validation identified walking speed cut-points that optimally discriminated those who reported mobility limitation from those who did not.

Results

Among 5043 women, CART analysis identified 2 cut-points, classifying 4144 (82.2%) with walking speed ≥0.75 m/s, which we labeled as “fast”; 478 (9.5%) as “intermediate” (walking speed ≥0.62 m/s but <0.75 m/s); and 421 (8.3%) as “slow” (walking speed <0.62 m/s). Among 13 589 men, CART analysis identified 3 cut-points, classifying 10 001 (73.6%) with walking speed ≥1.00 m/s (“very fast”); 2901 (21.3%) as “fast” (walking speed ≥0.74 m/s but <1.00 m/s); 497 (3.7%) as “intermediate” (walking speed ≥0.57 m/s but <0.74 m/s); and 190 (1.4%) as “slow” (walking speed <0.57 m/s). Prevalence of self-reported mobility limitation was lowest in the “fast” or “very fast” (11% for men and 19% for women) and highest in the “slow” (60.5% in men and 71.0% in women). Rounding the 2 slower cut-points to 0.60 m/s and 0.75 m/s reclassified very few participants.

Conclusions

Cut-points in walking speed of approximately 0.60 m/s and 0.75 m/s discriminate those with self-reported mobility limitation from those without.
Barriers to uptake of community-based health insurance in sub-Saharan Africa: a systematic review
Authors: Shewamene Zewdneh , Tiruneh Getachew , Abraha Atakelti , Reshad Abduljelil , Terefe Marta Minwyelet , Shimels Tariku , Lemlemu Eskedar , Tilahun Damitew , Wondimtekahu Adamu , Argaw Muluken , Anno Alemu , Abebe Firehiwot , Kiros Mizan
Published: June 2021

In the past two decades, community-based Health Insurance (CBHI) is expanding in most of sub-Saharan African countries with the aim of improving equitable access to health services for the informal sector population. However, population enrolment into CBHI and membership renewals thereafter remains stubbornly low. The purpose of this systematic review is to generate an evidence to better understand barriers to uptake of CBHI in sub-Saharan African countries. We systematically searched for relevant studies from databases: PubMed, Scopus, Cumulative Index of Nursing and Allied Health Literature (CINAHL), PsychInfo, ProQest, Excerpta Medica dataBASE (EMBASE) and Africa-Wide Information. The search strategy combined detailed terms related to (i) CBHI, (ii) enrolment/renewal and (iii) sub-Saharan African countries. A narrative synthesis of findings was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The protocol for this systematic review was registered with International Prospective Register of Systematic Reviews (PROSPERO) (ref: CRD42020183959). The database search identified 4055 potential references from which 15 articles reporting on 17 studies met the eligibility criteria. The findings revealed that barriers to uptake of CBHI in sub-Saharan Africa were multidimensional in nature. Lack of awareness about the importance of health insurance, socio-economic factors, health beliefs, lack of trust towards scheme management, poor quality of health services, perceived health status and limited health benefit entitlements were reported as barriers that affect enrolments into CBHI and membership renewals. The methodological quality of studies included in this review has been found to be mostly suboptimal. The overall findings of this systematic review identified major barriers of CBHI uptake in sub-Saharan African countries which may help policymakers to make evidence-informed decisions. Findings of this review also highlighted that further research with a robust methodological quality, depth and breadth is needed to help better understand the factors that limit CBHI uptake at individual, societal and structural levels in sub-Saharan Africa.
Pharmacodynamic Interactions Between Ketamine and Psychiatric Medications Used in the Treatment of Depression: A Systematic Review
Authors: Veraart Jolien K E , Smith-Apeldoorn Sanne Y , Bakker Iris M , Visser Berber A E , Kamphuis Jeanine , Schoevers Robert A , Touw Daan J
Published: June 2021

Background

The use of ketamine for depression has increased rapidly in the past decades. Ketamine is often prescribed as an add-on to other drugs used in psychiatric patients, but clear information on drug-drug interactions is lacking. With this review, we aim to provide an overview of the pharmacodynamic interactions between ketamine and mood stabilizers, benzodiazepines, monoamine oxidase-inhibitors, antipsychotics, and psychostimulants.

Methods

MEDLINE and Web of Science were searched.

Results

Twenty-four studies were included. For lithium, no significant interactions with ketamine were reported. Two out of 5 studies on lamotrigine indicated that the effects of ketamine were attenuated. Benzodiazepines were repeatedly shown to reduce the duration of ketamine’s antidepressant effect. For the monoamine oxidase-inhibitor tranylcypromine, case reports showed no relevant changes in vital signs during concurrent S-ketamine use. One paper indicated an interaction between ketamine and haloperidol, 2 other studies did not. Four papers investigated risperidone, including 3 neuroimaging studies showing an attenuating effect of risperidone on ketamine-induced brain perfusion changes. Clozapine significantly blunted ketamine-induced positive symptoms in patients with schizophrenia but not in healthy participants. One paper reported no effect of olanzapine on ketamine’s acute psychotomimetic effects.

Conclusion

Current literature shows that benzodiazepines and probably lamotrigine reduce ketamine’s treatment outcome, which should be taken into account when considering ketamine treatment. There is evidence for an interaction between ketamine and clozapine, haloperidol, and risperidone. Due to small sample sizes, different subject groups and various outcome parameters, the evidence is of low quality. More studies are needed to provide insight into pharmacodynamic interactions with ketamine.
Understanding complaints made about surgical departments in a UK district general hospital
Authors: CLAYDON Oliver , KEELER Barrie , KHANNA Achal
Published: June 2021

Background

Patient complaints are increasingly recognized to provide a valuable insight into patients’ experience of healthcare. Being local and subjective, they can bring to light previously under-appreciated causes of patient dissatisfaction. The focus of surgical care is usually an intervention, and the nature of complaints made about surgical care may vary substantially from that in non-surgical specialties. This may have specific implications for quality improvement in surgical departments.

Objective

To investigate the causes of patient dissatisfaction in surgical care.

Methods

We retrospectively examined the content and frequency of patient complaints received by surgical departments at a UK district general hospital in the calendar year 2017. Second-hand reports of complaints, documented by the members of the hospital’s complaints department, were collated from a prospectively maintained database and categorized by content.

Results

Three hundred and ninety-nine complaints were received over the study period. These related to the care of 327 different patients. One complaint was generated for every 111 patient encounters. Ninety-one per cent of the complaints were made by the patient, and 8.8% were made by a family member. Complaints cited communication with hospital staff in 25% of cases, out-of-hospital delays in 24%, clinical issues in 22%, hospital administration in 16% and in-hospital delays in 10%. Post-operative symptoms and complications accounted for only 2% of the complaints. Twenty-six per cent of the complaints resulted in the rescheduling of an operation or a clinic appointment. Seventeen per cent of the complaints prompted internal actions within the surgical department to investigate and learn from the incident.

Conclusion

The profile of complaints made about surgical departments is similar to that of non-surgical departments in other studies. Clinical issues represented only the third largest cause of complaints. More complaints implicated patient–staff communication, and around half implicated management-related issues. Improving staff communication training, clinical standards and hospital administration continues to represent opportunities to enhance the patients’ overall experience of surgical care.