bluuebunny/crossref_metadata_2025 huggingface dataset:
Broadband dielectric behaviour and structural characterization of PVDF/PMMA/OMMT polymer nanocomposites for promising performance nanodielectrics in flexible technology advances
Authors: Kumar Naresh , Sengwa R J
Published: June 2023

Characterization of broadband dielectric behaviour of polymer nanocomposites (PNCs) is vital for the exploration of efficient nanodielectrics as energy storage, flexible dielectric substrates, and insulators in a wide range of advanced electronic device technologies. Accordingly, herein, PNC films based on poly(vinylidene fluoride) (PVDF)/ poly(methyl methacrylate) (PMMA) blend matrix (80/20 wt/wt%) dispersed with 0, 2.5, 5, and 10 wt% organo-modified montmorillonite (OMMT) nanoclay are developed by state-of-the-art homogenized solution casting method. These PVDF/PMMA/OMMT compositions based flexible PNC films are characterized in detail by employing a scanning electron microscope (SEM) equipped with energy dispersive x-ray (EDX) device, x-ray diffractometer (XRD), Fourier transform infrared (FTIR) spectrometer, differential scanning calorimeter (DSC), inductance-capacitance-resistance (LCR) meter, and impedance/material analyzer (IMA). The SEM microimages, XRD traces, and FTIR spectra evidenced appreciable homogeneity and surface morphology, intercalated and exfoliated OMMT structures, and the α, β and γ-phase crystallites of the PVDF in these complex semicrystalline PNCs. The DSC thermograms confirmed a significant alteration in the melting temperature and degree of crystallinity of the PVDF crystallites with the increased amount of OMMT in the 80PVDF/20PMMA blend host matrix. The broadband dielectric dispersion spectra over the frequency range of 20 Hz−1 GHz explained the contribution of interfacial polarization in the complex dielectric permittivity at lower experimental frequencies, whereas at higher frequencies permittivity is ruled by dipolar polarization in these composites at 27 °C. The dielectric loss angle tangent and electric modulus spectra revealed an intense structural dynamics relaxation process in the upper radio frequency region. The influence of OMMT concentration on the dielectric permittivity and electrical conductivity is explored. The detailed dielectric and electrical characterization of these innovative semicrystalline composites with important structural and thermal properties revealed their immense potential as high-performance nanodielectrics for highlighting current applications of broadband frequency range electrical and electronic device technologies.
Independently tunable refractive index sensor based on metal-insulator-metal waveguide with key-shaped resonator and application in human blood plasma detection
Authors: Zhao Shiyu , Qi Yunping , Chen Haowen , Wen Yujiao , Wang Li , Zhou Zihao , Zhang Shu , Wang Xiangxian
Published: June 2023

In this paper, a metal-insulator-metal waveguide structure based on a key-shaped resonator is proposed. Firstly, the structure is simulated using the finite difference in time domain (FDTD) method, revealing the generation of three resonant peaks. And the theoretical results are then analyzed using multimode interference coupled mode theory (MICMT), demonstrating a high level of agreement with the simulation results. Then the parameters of the structure are adjusted, so that the resonant peaks can be tuned independently. Notably, the structure exhibits a maximum sensitivity of 1520 nm RIU−1 with a figure of merit (FOM*) of 195.89, highlighting its exceptional sensing capabilities. Additionally, an analysis of the asymmetric structure reveals the emergence of a new Fano resonance. Due to its outstanding sensing performance, the structure holds potential for applications blood plasma concentration testing. Feasibility is assessed in terms of blood plasma concentration detection, achiveing a maximum sensitivity of 3.07 nm l g−1. As a result, this structure offers promising opportunities in the field of on-chip optical integration and the biomedical field, among others.
Conversion of carbon dioxide in atmospheric pressure dielectric barrier discharges with different electrode configurations
Authors: Wang Chao , Wang Hai-Xing , Liu Chang-Yu , Meng Xian , Jin Guang-Yuan , Huang He-Ji , Cao Jin-Wen , Sun Su-Rong , Yan Cong
Published: June 2023

The choice of electrode configuration and dielectric material is critical to the discharge process and plasma characteristics of a dielectric barrier discharge (DBD) reactor. In this study, a new electrode configuration of DBD reactor with copper mesh as electrode inserted between dielectrics is proposed, which has a much higher capacitance than the conventional double-dielectric layer DBD reactor. Two materials with different relative dielectric permittivities, alumina and zirconia, are chosen as dielectrics for an experimental comparison of CO2 decomposition. The experimental results show that the conversion rate of CO2 for the reactor with copper mesh inserted between dielectrics are higher than that of the corresponding double dielectric layer reactor under the same discharge power, and the conversion rate of CO2 with zirconia as a dielectric material is higher than the case of alumina as a dielectric. Further analysis of discharge characteristics shows that for the reactor with copper mesh inserted between dielectrics, the applied voltage required for discharge is significantly reduced, the amount of transferred charge is significantly increased, and the number of micro-discharge current pulses as well as the average lifetime during a single voltage cycle are also considerably increased, leading to an increase in the CO2 discharge efficiency and conversion rate.
Multi-Watt cavity for 266 nm light in vacuum
Authors: Brand Christian , Knobloch Christian , Simonović Ksenija , Arndt Markus
Published: June 2023

Intense coherent ultraviolet radiation is gaining increasing importance in advanced quantum technologies—from optical clocks and quantum computers to matter-wave interferometry—as well as in photochemistry, life sciences, semiconductor industry, and space applications. Since the preparation of multi-Watt light sources is still an open challenge for many ultraviolet wavelengths, resonant enhancement in a cavity is an attractive alternative. However, many experiments with atoms, molecules or nanoparticles require isolation in high vacuum where UV optics often show fast degradation. Here, we present stable performance of a cavity for 266 nm light with several Watt of intra-cavity power in high vacuum despite the presence of hydrocarbons. Comparing two sets of cavity mirrors indicates that this feat is connected to the micro-chemical environment at the topmost coating layer. Our study emphasizes the need for further developments in this direction to facilitate robust, compact, and high-performing devices employing UV radiation.
Bionic Porous Design and Mechanical Response of Short Implants
Authors: Zhang Xiao , Zhang Jinyang , Chen Jianyu , Chen Xianshuai
Published: June 2023

Due to the material itself and the traditional geometric design, short implants have the problems of high stiffness, less osseointegrated area, and lower long-term reliability in clinical application. In this research, short implants with various porous structures were constructed and their biomechanical responses were evaluated, including biomechanical properties, compression capability, and stress distribution of surrounding bone tissue. Thus, three types of short implants were built: the diamond-like porous short implant (5.0 × 5.0 mm), the hexahedral porous short implant (5.0 × 5.0 mm), and the solid short implant (5.0 × 5.0 mm). Three implant-supported prosthetic models were built based on the above three implants, and their static mechanical properties were assessed. Besides, the average stiffness of regular cylindrical samples was calculated by compression test simulation. The result confirmed that hexahedral porous short implants showed minimum peak stress compared with the diamond-like porous and solid short implants. Similarly, the value of stress peaks in the bone-implant interface for the hexahedral porous short implant appeared lower than the other two short implants. Compression simulation indicated the average stiffness of cylinders after diamond-like and hexahedral porous design was 92.2% and 56.3% lower than the solid cylinder. Compared with the other two designs, the hexahedral porous short implant obtained better stress distribution, even avoiding bone overstress.
Mechanical behaviors and failure mechanisms of CMDB propellant under wide strain rate tension loading
Authors: Yin Jianping , Li Meng , Du Wenxuan , He Xuanfu , Song Jun , Hu Bowen , Huang Meng , Li Yang , Miao Yinggang
Published: June 2023

Composite modified double-base (CMDB) is a sort of mature propellant with a stable structure and high performance. Its tensile mechanical properties should be considered in the structural integrity design of solid propellant charges. The tensile tests were performed on the CMDB by a quasi-static measurement machine. The Hopkinson tension bar (SHTB) under strain rates from 0.0001s−1 to 2500s−1 was modified for structural integrity evaluation, and the stress-strain curves were accurately obtained. After comparing under different strain rates, the results show that the initial modulus of elasticity and stress level are significantly affected by the level of strain rate. Furthermore, the strain hardening becomes more distinct with increasing strain rates. Failure specimens were observed by scanning electron microscopy (SEM). It is indicated that the failure under a low strain rate is mainly debonding of filled particles from the matrix. However, it is mainly caused by their embrittlement under dynamic loading.
Mechanical properties of carbon steel under uniaxial static tension
Authors: Wang Zhuolin
Published: June 2023

With the continuous development of science and technology, carbon steel is widely used in production and life. Especially at the practical application level, in the engineering application, the analysis of the mechanical properties of carbon steel materials has become increasingly prominent. The tensile test is a mechanical property test in which a standard tensile specimen is pulled to fracture at a specified tensile speed under the continuous action of static axial tensile force. The force and elongation are continuously recorded during the tensile process so as to obtain its strength criterion and plasticity criterion. In this paper, the characteristics of mechanical properties of the high, medium, and low carbon steels under uniaxial static tension are discussed. The reasons for the different mechanical properties of steels with different carbon content are explained from a microscopic perspective. The study provides some basic assistance to those who need relevant information.
Mechanical Properties of Seawater Sea-sand Recycled Concrete in Sulfate Attack Environment
Authors: Tian Xiangsheng , Huang Yijie , Zhang Jingxue , Ma Xiaoli
Published: June 2023

Seawater sea-sand recycled concrete (SSRAC) is a new sort of green concrete, it has good environmental and economic benefits. In this paper, the dry-wet cycle and full immersion erosion environments is simulated. The change characteristics of mechanical properties of SSRAC under sulfate attack are studied and compared with ordinary concrete (OC) and freshwater river sand recycled concrete (RAC). The test shows that compared with immersion erosion, the dry-wet cycle significantly accelerates the deterioration rate of concrete. For the concrete in full immersion condition, the strength is still in the rising stage when the immersion corrosion to 120 d, and there is no obvious change of appearance. In dry-wet cycles, apparent damage gradually extends from the diagonal to the surrounding. The damage deterioration starts from the surface layer and gradually deepens. The prismatic compressive strength and corrosion resistance coefficient of SSRAC show the same law as OC and RAC, which increases first and then decreases. The corrosion resistance coefficient is lower than 75% at 120 cycles. The sulfate resistance of SSRAC is significantly inferior to OC and slightly greater than RAC.
An investigation on the effect of thread pitch on the self-loosening of bolted joint caused by fretting wear
Authors: Zhang Mingyuan , Huang Yuanzhe , Liu Haining , Li Fajia , Cai Yuquan
Published: June 2023

To study the effect of thread pitch on the bolt loosening behavior with consideration of fretting wear, the loosening experiments and finite element analysis were carried out to the bolts with different thread pitches. The experimental results demonstrate that fretting wear existed on the thread surface. It caused a slow bolt loosening without the nut rotation. With the thread pitch increases, the clamping force will become smaller, so that the fretting wear on the thread surface will also decrease, indicating that lager thread pitch could increase the anti-loosening ability through alleviating the fretting wear. The FE (Finite Element) results show that the decrease of sliding distance on thread surface had more beneficial effects than the increase of contact stress on the reduction in the fretting wear for the bolt with larger thread pitch.
Simulation study of nanomaterials in heat pipe enhanced high power LED heat sink
Authors: Huang Haibo , Huang Xiaohua , Cheng Zaijun , Wang Yuanzhang
Published: June 2023

To facilitate the simulation of heat dissipation of high-power LED lamps, a set of simplified models for tubular heat pipes and carbon nanotube arrays were first established to estimate their thermal conductivity. Then several kinds of radiators were designed. The application of nanomaterials and heat pipes in the heat dissipation of lamps was studied by the finite element method. It is found that the radiator with vertical suspended fins strengthened by a heat pipe and heat dissipation coating has a better heat dissipation effect than other radiators. Finally, the simulation study of thermal interface materials and heat dissipation coatings for lamps and lanterns heat dissipation is carried out. The results show that the thermal interface materials of carbon nanotubes and carbon nano coatings can enhance the heat dissipation performance of lamps.
Straight recycled green fibre pull-out behaviour in an ultrahigh performance concrete composite matrix UHPC
Authors: Li Yan , Nyathi Tinashe Daniel , Dong Wenyang
Published: June 2023

This article presents the study of the pull-out method and the behavior of the cementitious matrix under loading. Using finite element analysis to investigate the interfacial debonding performance allows us to grasp the experiment’s estimated values. The mechanical bonding is determined using a Scanning Electron Microscopy SEM image. The slippage during the pull-out load varies depending on the cementitious matrix grade and whether the recycled steel strand is hooked at specific angles (Inclination angle). The relationship between monotonic loading and steel fiber diameter was found to be a direct proportion. To comprehend the bonding and debonding between surfaces, as well as the shear experience under loading, both studies find the correlation between theoretical and experimental results to be satisfactory. All aspects were discussed in relation to the effective use of a finite element method in analysis.
Exact solutions for compact stars in general relativity
Authors: Raghoonundun A , Bell R , Hobill D
Published: June 2023

Complete, exact, analytic solutions to the spherically symmetric Einstein equations have been constructed. Beginning with the Tolman VII solution we first “complete” the solution by computing an expression for the pressure and subsequently the equation of state. The Tolman VII solution is then extended to include non-zero mass densities at the fluid-vacuum interface. The method developed to construct these solutions is extended to include transverse pressures and charge. Furthermore the quadratic density profile of the Tolman VII type solutions is modified to include quartic density profiles that lead to expressions in terms of Jacobi elliptic integrals. It is shown that, depending on the outer boundary conditions placed on the mass density, the equations of state lead to either a set of polytropes or behaviour that mimics strange quark matter.
The Importance of the Pressure Anisotropy Induced by Strong Magnetic Fields on Neutron Star Physics
Authors: Ferrer Efrain J , Hackebill Aric
Published: June 2023

In this paper we discuss in some detail how the pressures determined from semi-classical statistical averaging of the energy momentum tensor in the presence of a uniform background magnetic field are anisotropic with different pressures arising along and perpendicular to the magnetic field direction. Hence, we analyze how this result can affect two important characteristics of dense magnetized systems: (i) The hadron-quark phase transition in the presence of a magnetic field, (ii) The behavior of the speed of sound in dense magnetized systems. Taking into account that large magnetic fields are expected to be present in the interior of neutron stars, we will stress the role the pressure anisotropy plays in the physics of these compact astronomical objects.
Readout Electronics for Spatial Distribution Measurement of Neutron Beam Flux in BNCT
Authors: Jiang W. , Cao P. , Liu X. , Fang Z. , Zhang Z. , An Q. , Shi B. , Chen J.
Published: June 2023

Boron neutron capture therapy (BNCT) is a promising cancer
treatment that selectively destroys tumor cells using a neutron
beam. However, accurately and fast measuring the spatial
distribution of neutron flux is critical to ensuring effective
treatment. To address this challenge, Micromegas detectors are
applied for the first time to measure the spatial distribution of
neutron beam flux in BNCT. Due to the high flux, large area, and
multiple components of the BNCT beam, the design of readout
electronics that can handle high counting rate, large channel
numbers, high integration, and discrimination of multiple beam
components is challenging. This paper proposes a targeted readout
electronics system to overcome this challenge. A modular readout
structure based on the PCI Express (PXIe) platform is designed for
384-channel readout. A fully parallel readout structure is developed
and fast shaper parameters are optimized to achieve high counting
rate for each readout channel. A multi-channel high-speed,
large-capacity caching technique is developed to address the
high-speed data storage problem. Digital shapers are implemented in
field-programmable gate array (FPGA) to achieve high
integration. Tests demonstrate that each readout channel can support
a counting rate of 800 kHz and achieve an excellent position
resolution of 1.4 mm. Furthermore, final tests on the BNCT beam
confirm that our system can successfully measure the flux spatial
distribution of different neutron components.
The effect of farmer’s characteristics to arabica coffee farmer’s performances
Authors: Rico  , Darma R , Salman D , Mahyuddin
Published: June 2023

Characteristics of farmers show the performance of farmers in running better and more sustainable farming. This study aims to analyze farmer characteristics’ effect on Arabica coffee farmers’ performance in North Toraja Regency. This study used a survey method with a quantitative descriptive approach. This research was conducted in North Toraja Regency on March 2022. The effect of farmer characteristics on farmer performance was analyzed using multiple linear regression analysis. Investigating the impact of farmer characteristics on farmer performance, it was found that farmer characteristics (gender, age, education, farming experience, family responsibilities, and income) had a positive influence on farmer performance.
Bird composition as an environmental quality indicator in Wallacea’s urban area
Authors: Arini D I D , Kinho J , Mayasari A , Irawan A F , Kafiar Y
Published: June 2023

North Sulawesi Province, part of Wallace Bioregion, has a complex ecosystem. Advanced urban development brings various impacts, such as environmental change. Birds’ existence around human provides some advantages, such as assisting the process of plant pollination, controlling insect populations, and indicators of environmental quality. This study aimed to determine the bird species composition in four locations and the environmental quality was analysed using the Bird Community Index (BCI). This study gathered data on bird species in Manado Bay, Gunung Tumpa, Kawanua Arboretum, and the Kaki Dian areas. We conducted field observation through point count method as primary data and the secondary data were obtained from previous publications. Data were analyzed using Bird Community and Sorenson indexes. This study revealed that the birds’ quantities and composition moderately varied in four locations. This study found 37 bird species in Manado Bay, 33 in Tumpa Mountain, 36 in Kawanua Arboretum, and 49 in the Klabat mountain areas. The Bird Community Index (BCI) accumulation ranged from 56.0 – 68.4 and it was categorized as medium environmental quality. Sorensen’s community similarity index displayed a value of 30.3-51.0% which classified as low to medium community similarity.
A study on seed germination of Senna alata (L.) (ketepeng)
Authors: Garvita R V , Ismaini L , Damayanti F , Lailaty I Q , Surya M I , Harto  , Nudin
Published: June 2023

Senna alata (L.) Roxb., locally known as “Ketepeng China” from the family of Fabaceae, is a shrub or small tree that is used as an ornamental flowering shrub and for medicinal purposes in tropical and subtropical countries. Various parts of S. alata plant (leaves, flowers, roots, or stem) are used in traditional medicines to treat typhoid, diabetes, malaria, asthma, ringworms, scabies, and eczema. The present study was designed to investigate plant conservation by establishing an efficient seed germination method. The seeds of S. alata responded differently in growth to each location and medium. The best result-produced seedlings are grown in pots filled with sand, both at Bogor and Cibodas. The percentage of seed germination on sand was higher (around 96.7%) than on husk media (about 10%) for 10 planting days.
Effect of several reduced-risk insecticides on the population of Bemisia tabaci Genn. and incidence of pepper yellow leaf curl Indonesia virus (PepYLCIV) on chili plants
Authors: Amaliah I K , Daud I D , Nasruddin A
Published: June 2023

Tobacco whitefly, Bemisia tabaci Genn. can directly, and indirectly damage chili plants by sucking the plant sap and transmitting Pepper yellow leaf curl Indonesia virus (PepYLCIV), respectively. Farmers control PepYLCIV by using synthetic insecticides with 2-3 applications a week to suppress the vector population. The intensive use of insecticide raises concern about potential detrimental effects on the environment and non-target organisms. An alternative control measure for B. tabaci is the use of reduced-risk insecticides that are effective but safer. Thus, the study aimed to determine the effectiveness of various reduced-risk insecticides in reducing the whitefly population and PepYLCIV incidence. This experiment consisted of 12 treatments using insecticides of abamectin, azadiractin, imidacloprid, deltamethrin, spinosad, and water (control), applied once and twice a week. The results showed that the low-risk insecticides had no significant effect on the numbers of adults and nymphs of B. tabaci and the PepYLCIV incidence. Imidacloprid had significantly lower egg number and PepYLCIV incidence than the control and the other insecticide treatments. Our results also showed that B. tabaci populations were low throughout the season but the incidences of PepYLCIV were relatively high. This indicated a possibility that PepYLCIV is seed-borne.
Detection of citrus vein phloem degeneration disease (Candidatus Liberibacter asiaticum) in orange cv. Selayar, Citrus reticulata L.
Authors: Patandjengi B , Farham M , Kuswinanti T , Melina  , Asman  , Tuwo M
Published: June 2023

CVPD disease (Huanglongbing) is the most severe citrus disease caused by the bacterium Cand. Liberibacter asiaticus. This pathogen lives in the phloem tissue of citrus plants and is transmitted through the vector Diaphorina citri and by grafting. The study aimed to know the presence of CVPD disease in Orange cv Selayar nurseries and mother tree gardens in the Selayar Islands Regency. The PCR test was carried out in the research using the Laboratory of Agricultural Biotechnology, Hasanuddin University. The DNA of the citrus leaves was extracted using the Genomic DNA Kit method and the DNA CLas was amplified using the polymerase chain reaction (PCR) with the primer pairs OI1-O12c. The results showed that the percentage of mother plants of orange cv. Selayar infected with CVPD-like symptoms were 10-21 %. The percentage of citrus seedlings with CVPD-like symptoms in 2 nurseries were 0.27% and 0.09%. The symptoms of CVPD disease have been confirmed using a PCR technique, which was successful in amplifying the DNA fragment of CLa measuring 1160 bp, although not all symptoms suspected of CVPD are confirmed positive.
Diversity of insects on bitti stands (Vitex cofassus)
Authors: Budiaman  , Nuraeni S , Ramli
Published: June 2023

Insects are the most abundant group of animals compared to other animal groups, this is related to the high adaptability of insects to various types of habitats. This study aims to analyze the diversity of soil surface insects and arboreal insects (nocturnal and diurnal) on bitti stands (Vitex cofassus) in Belabori Village, Parangloe District, Gowa Regency. Data collection was carried out for 2 months starting from October to November 2019 using 3 trap techniques (Sweep Net, Pitfall Trap, Light Trap). The results showed that the insects caught each consisted of 8 orders, 19 families, 28 types and a total of 231 individuals divided into 45 soil-surface insects, 163 nocturnal insects and 21 diurnal insects. The order most commonly found in ground-level insects is the order Hymenoptera while the arboreal insects (Nocturnal and Diurnal) are the order Coleoptera. The Shanon-Wieiner (H’) diversity index category in bitti stands in ground-level insects and arboreal insects (Nocturnal and Diurnal) is classified as a medium category and the Margalef species wealth index (Dmg) is classified as a low category.
Failure of local institutions of coastal communities to conserve mangroves
Authors: Salampessy M L , Lidiawati I , Metkono E
Published: June 2023

The community and the ecosystem in its surroundings benefit greatly from the ecosystem services provided by mangroves. It is critical to understand how local institutions contribute to the management of mangrove forests. The purpose of this study is to identify and evaluate local institutions involved in coastal mangrove forest management. The study was carried out in the Indonesian village of Pantai Bahagia Muara Gembong. Key informant interviews and observation were used to acquire the data. The situation, structure, behavior, and performance (SSBP) method was used to examine the data. Research results: The situation shows the increasing damage to mangrove forests due to the increasing conversion of land as rice fields and ponds, the structure illustrates that the community does not yet have formal norms and rules that help manage community activities in mangrove forest conservation, Behavior Describing the various interests and perception of the community and parties in utilizing the potential of mangrove forests, as well as the absence of coordination and cooperation with stakeholder in forest management and performance shows that weak community institutions and coordination with parties so that mangrove forest damage continues to occur and has implications for frequent tidal floods, disruption of economic activities.
Selected non-timber forest products (NTFPS) commodity for future green economy-based products development in Papua Province
Authors: Ap A T , Wahyudi  , Allo A G
Published: June 2023

Non-timber forest products (NTFPs) play significant roles in the daily livelihood of the forest communities’ dependence, local forest management practices, and forest resource sustainability in Papua Province. This research is designed to identify, characterize, and examine the roles of the NTFPs to local communities in Papua Province to be nominated and developed as green economy-based commodities in Papua. Document analysis, literature review, and an interview with the selected respondents are conducted to collect the data. The 7th Forest Management Units (FMU) and the 4th Forestry and Environment Branch across Papua Province will be selected as targeted research areas. The results indicated that the 21 NTFPs-based commodities were identified, and could be developed and promoted as green economy-based products. There are ranging from essential oils, agarwood, noken, mangrove derivate products, honey, coffee, masohi’s bark, sago, ginger-based products, ecotourism, palm peanuts, cocoa, fish-based products, seaweed, and others. Each FMU has candidature products commodities to be developed as green economy products, and the future development program is highly needed to be formulated.
‘That’s as hard a decision as you will ever have to make’: the experiences of people who discussed Do Not Attempt Cardiopulmonary Resuscitation on behalf of a relative during the COVID-19 pandemic
Authors: Tomkow Louise , Dewhurst Felicity , Hubmann Michaela , Straub Christina , Damisa Efioanwan , Hanratty Barbara , Todd Chris
Published: June 2023

Background

COVID-19 brought additional challenges to Do Not Attempt Cardiopulmonary Resuscitation (DNACPR) decision-making, which was already a contentious issue. In the UK, reports of poor DNACPR decision-making and communication emerged in 2020, including from the regulator, the Care Quality Commission. This paper explores the experiences of people who discussed DNACPR with a healthcare professional on behalf of a relative during the coronavirus pandemic, with the aim of identifying areas of good practice and what needs to be improved.

Methods

a total of 39 people participated in semi-structured interviews via video conferencing software or telephone. Data were evaluated using Framework Analysis.

Findings

results are presented around three main themes: understanding, communication and impact. Participants’ understanding about DNACPR was important, as those with better understanding tended to reflect more positively on their discussions with clinicians. The role of relatives in the decision-making process was a frequent source of misunderstanding. Healthcare professionals’ communication skills were important. Where discussions went well, relatives were given clear explanations and the opportunity to ask questions. However many relatives felt that conversations were rushed. DNACPR discussions can have a lasting impact—relatives reported them to be significant moments in care journeys. Many relatives perceived that they were asked to decide whether their relative should receive CPR and described enduring emotional consequences, including guilt.

Conclusion

the pandemic has illuminated deficiencies in current practice around DNACPR discussion, which can have difficult to anticipate and lasting negative consequences for relatives. This research raises questions about the current approach to DNACPR decision-making.
Towards Accurate Smartphone Localization Using CSI Measurements
Authors: Yang Runze , Huang Baoqi , Xu Zhendong , Jia Bing , Xu Gang
Published: June 2023

In comparison with capturing channel state information (CSI) measurements via a laptop or desktop, using a smartphone to collect CSI measurements incurs the restriction of working with a single access point and significant signal distortions, resulting in limited information for smartphone localization. Therefore, this paper intends to leverage as much available localization information as possible by ($1$) shifting the WiFi frequency from $2.4$ to $5$GHz; ($2$) calibrating the noisy CSI measurements and ($3$) fusing both amplitudes and phases of the CSI measurements, so as to enhance localization accuracy. Specifically, we first filter out distorted CSI measurements based on their distribution characteristics, then apply the advanced uniform manifold approximation and projection method to refine the mapping relations from a high-dimensional fingerprint space to a low-dimensional location space, and design a location fusion algorithm based on the continuous feature scaling model, which is able to distinguish two locations with similar fingerprints. Extensive experimental results show that the localization accuracy of the proposed approach outperforms the state-of-the-art counterparts by at least $15.5$ and $18.7\%$ using two off-the-shelf smartphones.
Visceral Fat Indices: Do They Help Differentiate Crohn’s Disease and Intestinal Tuberculosis in Children?
Authors: Seetharaman Jayendra , Srivastava Anshu , Yadav Rajanikant R , Singh Sumit K , Mishra Prabhakar , Sen Sarma Moinak , Poddar Ujjal
Published: June 2023

Background and Aims

Crohn’s disease [CD] and intestinal tuberculosis [ITB] are often difficult to differentiate. Mesenteric fat hypertrophy is a feature of CD. We evaluated the utility of fat indices (visceral fat [VF] and subcutaneous fat [SF]) in differentiating CD and ITB in children.

Methods

Symptomatic children diagnosed to have CD or ITB based on recommended criteria were enrolled. Clinical, anthropometric, and laboratory details were noted. Abdominal fat was measured on computed tomography in supine position at the level of L4 vertebrae. VF and SF area was measured separately by a radiologist, blinded to the diagnosis. The sum of VF and SF was taken as total fat [TF]. VF/SF and VF/TF ratios were calculated.

Results

Thirty-four (age 14 years [10.8–17.0], 14 boys) children were recruited: 12 had CD [seven boys, age 13.0 years] and 22 had ITB [seven boys, age 14.5 years]. VF area was higher in CD compared to ITB (18.34 cm2 [15.62–40.01] vs 6.48 cm2 [2.65–21.96]; p = 0.012). The SF and TF area was similar in ITB and CD. The ratios of VF/SF (0.82 [0.57–1.5] vs 0.33 [0.16–0.48]; p = 0.004) and VF/TF (0.45 [0.36–0.60] vs 0.25 [0.13–0.32]; p = 0.004) were significantly higher in CD. On comparing CD and ITB in boys and girls separately, the difference was significant for boys but not for girls. A VF/SF ratio of 0.609 predicted CD with a good sensitivity [75%] and specificity [86.4%] [area under the curve 0.795, 95% confidence interval 0.636–0.955; p = 0.005].

Conclusion

The VF/SF ratio is a simple, non-invasive, objective parameter to differentiate CD and ITB in children, particularly boys. Larger studies are needed to validate this in girls.
Delineating the Seasonality of Varicella and Its Association With Climate in the Tropical Country of Colombia
Authors: Barrero Guevara Laura Andrea , Goult Elizabeth , Rodriguez Dayanne , Hernandez Luis Jorge , Kaufer Benedikt , Kurth Tobias , Domenech de Cellès Matthieu
Published: June 2023

Background

Varicella causes a major health burden in many low- to middle-income countries located in tropical regions. Because of the lack of surveillance data, however, the epidemiology of varicella in these regions remains uncharacterized. In this study, based on an extensive dataset of weekly varicella incidence in children ≤10 during 2011–2014 in 25 municipalities, we aimed to delineate the seasonality of varicella across the diverse tropical climates of Colombia.

Methods

We used generalized additive models to estimate varicella seasonality, and we used clustering and matrix correlation methods to assess its correlation with climate. Furthermore, we developed a mathematical model to examine whether including the effect of climate on varicella transmission could reproduce the observed spatiotemporal patterns.

Results

Varicella seasonality was markedly bimodal, with latitudinal changes in the peaks' timing and amplitude. This spatial gradient strongly correlated with specific humidity (Mantel statistic = 0.412, P = .001) but not temperature (Mantel statistic = 0.077, P = .225). The mathematical model reproduced the observed patterns not only in Colombia but also México, and it predicted a latitudinal gradient in Central America.

Conclusions

These results demonstrate large variability in varicella seasonality across Colombia and suggest that spatiotemporal humidity fluctuations can explain the calendar of varicella epidemics in Colombia, México, and potentially in Central America.
Characterizing subgroup performance of probabilistic phenotype algorithms within older adults: a case study for dementia, mild cognitive impairment, and Alzheimer’s and Parkinson’s diseases
Authors: Banda Juan M , Shah Nigam H , Periyakoil Vyjeyanthi S
Published: June 2023

Objective

Biases within probabilistic electronic phenotyping algorithms are largely unexplored. In this work, we characterize differences in subgroup performance of phenotyping algorithms for Alzheimer’s disease and related dementias (ADRD) in older adults.

Materials and methods

We created an experimental framework to characterize the performance of probabilistic phenotyping algorithms under different racial distributions allowing us to identify which algorithms may have differential performance, by how much, and under what conditions. We relied on rule-based phenotype definitions as reference to evaluate probabilistic phenotype algorithms created using the Automated PHenotype Routine for Observational Definition, Identification, Training and Evaluation framework.

Results

We demonstrate that some algorithms have performance variations anywhere from 3% to 30% for different populations, even when not using race as an input variable. We show that while performance differences in subgroups are not present for all phenotypes, they do affect some phenotypes and groups more disproportionately than others.

Discussion

Our analysis establishes the need for a robust evaluation framework for subgroup differences. The underlying patient populations for the algorithms showing subgroup performance differences have great variance between model features when compared with the phenotypes with little to no differences.

Conclusion

We have created a framework to identify systematic differences in the performance of probabilistic phenotyping algorithms specifically in the context of ADRD as a use case. Differences in subgroup performance of probabilistic phenotyping algorithms are not widespread nor do they occur consistently. This highlights the great need for careful ongoing monitoring to evaluate, measure, and try to mitigate such differences.
Navigating the empty shell: the role of articulation work in platform structures
Authors: Huber Linda , Pierce Casey
Published: June 2023

This article explores platform workers’ strategies for producing sustainable, quality services within platform structures that simultaneously over- and under-determine their work. We present findings from interviews with U.S.-based mental health professionals (n = 48) working on teletherapy platforms. These therapists describe navigating both the presence of platformic controls and the absence of features supporting professional best practices and regulatory requirements. We describe this absence as the “empty shell” characteristic of platforms and argue that it is a central technique through which platforms create scale. Our findings detail the communicative strategies therapists employ to navigate the empty shell and provide quality care to their clients. These strategies can be seen as a form of “articulation work,” a concept drawn from the sociology of work. Attending to articulation work in an emerging platform labor context, such as teletherapy, contributes to our understanding of the politics of platforms.
Surveillance and the future of work: exploring employees’ attitudes toward monitoring in a post-COVID workplace
Authors: Vitak Jessica , Zimmer Michael
Published: June 2023

The future of work increasingly focuses on the collection and analysis of worker data to monitor communication, ensure productivity, reduce security threats, and assist in decision-making. The COVID-19 pandemic increased employer reliance on these technologies; however, the blurring of home and work boundaries meant these monitoring tools might also surveil private spaces. To explore workers’ attitudes toward increased monitoring practices, we present findings from a factorial vignette survey of 645 U.S. adults who worked from home during the early months of the pandemic. Using the theory of privacy as contextual integrity to guide the survey design and analysis, we unpack the types of workplace surveillance practices that violate privacy norms and consider attitudinal differences between male and female workers. Our findings highlight that the acceptability of workplace surveillance practices is highly contextual, and that reductions in privacy and autonomy at work may further exacerbate power imbalances, especially for vulnerable employees.
Information sharing in a hybrid workplace: understanding the role of ease-of-use perceptions of communication technologies in advice-seeking relationship maintenance
Authors: Wu Y Jasmine , Antone Brennan , DeChurch Leslie , Contractor Noshir
Published: June 2023

Shifts to hybrid work prompted by the COVID-19 pandemic have the potential to substantially impact social relationships at work. Hybrid employees rely heavily on digital collaboration technologies to communicate and share information. Therefore, employees’ perceptions of the technologies are critical in shaping organizational networks. However, the dyadic-level misalignment in these perceptions may lead to relationship dissolution. To explore the social network consequences of hybrid work, we conducted a two-wave survey in a department of an industrial manufacturing firm (N = 169). Our results show that advice seekers were less likely to maintain their advice-seeking ties when they had a mismatch in ease-of-use perceptions of technology with their advisors. The effect was more substantial when advice seekers spent more time working remotely. The study provides empirical insights into how congruence in employees’ perceptions of organizational communication technologies affects how they maintain advice networks during hybrid work.
Speech production under uncertainty: how do job applicants experience and communicate with an AI interviewer?
Authors: Liu Bingjie , Wei Lewen , Wu Mu , Luo Tianyi
Published: June 2023

Theories and research in human–machine communication (HMC) suggest that machines, when replacing humans as communication partners, change the processes and outcomes of communication. With artificial intelligence (AI) increasingly used to interview and evaluate job applicants, employers should consider the effects of AI on applicants’ psychology and performance during AI-based interviews. This study examined job applicants’ experience and speech fluency when evaluated by AI. In a three-condition between-subjects experiment (N = 134), college students had an online mock job interview under the impression that their performance would be evaluated by a human recruiter, an AI system, or an AI system with a humanlike interface. Participants reported higher uncertainty and lower social presence and had a higher articulation rate in the AI-evaluation condition than in the human-evaluation condition. Through lowering social presence, AI evaluation increased speech rate and reduced silent pauses. Findings inform theories of HMC and practices of automated recruitment and professional training.
Toward work’s new futures: Editors’ Introduction to Technology and the Future of Work special issue
Authors: Baym Nancy , Ellison Nicole B
Published: June 2023

This special issue is based in the belief that theoretically informed, methodologically diverse, and sociotechnically inspired research is our best approach for understanding contemporary entanglements between the technological and social aspects of work, and for grappling with what that means for our futures. In this Editors’ Introduction to JCMC’s Technology and the Future of Work special issue, we synthesize emergent themes across the eleven papers included and reflect on productive analytic lenses for anticipating how technologies may shape social and work practices, and vice versa. We identify four themes woven across the papers—visibility, relationships, boundaries, and power—and explicate some of the ways that social, technical, temporal, and communicative dimensions of work emerge across a variety of work contexts. Together, these papers highlight the creative, sense-making, and collaborative dynamics of the technologically infused workplace while acknowledging the amorphous nature of work and place, past, present and future.
Hansen Lecture 2022: The Evolution of the Use of Models in Survey Sampling
Authors: Valliant Richard
Published: June 2023

Morris Hansen made seminal contributions to the early development of sampling theory, including convincing government survey administrators to use probability sampling as opposed to nonprobability (NP) methods like quota sampling. He codified many of the early results in design-based sampling theory in his 1953 two-volume set co-authored with Hurwitz and Madow. Since those developments, the explicit use of models has proliferated in sampling for use in basic point estimation, nonresponse and noncoverage adjustment, imputation, and a variety of other areas. This paper summarizes some of the early developments, controversies in the design-based versus model-based debate, and uses of models for inference from probability and NP samples.
(007) Physical activity and female sexual dysfunction: too much of a good thing?
Authors: Maseroli E , Rastrelli G , Di Stasi V , Cipriani S , Scavello I , Todisco T
Published: June 2023

Introduction

Research on the relationship between physical activity (PA) and female sexual dysfunction (FSD) is lacking.

Objectives

To investigate the clinical, psychological, and sexual correlates of PA in women with FSD.

Methods

A non-selected series of n=322 pre- and post-menopausal patients consulting for FSD was retrospectively studied. Regular involvement in PA and its frequency (<1 hour/week: sedentary, 1-3 hours/week: active, 4-6 hours/week: very active, >6 hours/week: extremely active) were investigated with a specific question. FSDs, including HSDD (Hypoactive sexual desire disorder) and FGAD (Female genital arousal disorder), were diagnosed according to a structured and clinical interview. Participants underwent a physical examination and a clitoral Doppler ultrasound, and were asked to complete the Female Sexual Function Index (FSFI), Female Sexual Distress Scale-Revised (FSDS-R), Body Uneasiness Test (BUT), and Middlesex Hospital Questionnaire (MHQ).

Results

At multivariate analysis, women engaging in PA (67.4%, n=217) scored significantly higher in several FSFI domains - including desire, arousal and lubrication - and showed lower sexual distress and lower resistance of clitoral arteries, as compared to sedentary women. A significant, inverse association between PA and HSDD was observed. Mediation analysis demonstrated that the negative association between PA and HSDD was partly mediated by body image concerns (BUT Global severity index), psychopathological symptoms (MHQ total score) and sexual distress (FSDS-R score). These latter two factors also partly mediated the association between PA and a reduced risk of FGAD, whilst a lower BMI was a full mediator in the relationship between PA and FGAD. Finally, extreme PA was associated with significantly worse scores in several psychosexual parameters (i.e. sexual satisfaction and histrionic/hysterical symptoms), even compared to a sedentary lifestyle.

Conclusions

In women with FSD, PA was associated with better sexual function and clitoral vascularization, lower sexual distress and reduced odds of HSDD and FGAD; the benefits of PA on sexuality were mediated by both psychological and organic determinants; excessive PA was related with a poor overall sexual function and with a low sexual satisfaction.

Disclosure

No.