bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on Heat Transfer Characteristics and Typical Parameters Sensitivity Analysis of the Deep Borehole Heat Exchanger Combined With the Geothermal Wells
Authors: Ma Jiuchen , Zhang QiuLi , Yi Feiyu , Jiang Qian , Xie Yacheng , Wang Yahui
Published: September 2021

Based on abundant hydrothermal geothermal resources at the depth of 1000–2000 m formation in the basin of the BoHai Bay, the deep borehole heat exchanger (DBHE) combined with the geothermal wells is proposed. According to the modified thermal resistance and capacity model (MTRCM), the heat transfer models inside and outside borehole are established. The transient analytical solutions which are the vertical temperature profiles in the inlet (outlet) pipe and the grout of the DBHE and the corresponding dimensionless form are obtained by deducing and solving the heat transfer models inside the borehole. The mathematical model and the analytical solutions are validated by the experimental data and existing studied data. This paper utilizes respectively the Matlab2012 and the Feflow7.1 to solve the heat transfer models inside and outside the DBHE. The sensitivity analysis is performed to examine the influence of typical parameters on the DBHE heat transfer characteristics, including the quantity of geothermal water exploitation, the well distance between the pumping well and the DBHE, the DBHE inlet temperature, the DBHE depth, and the flowrate of circulating water. Under the action of geothermal wells, the heat transfer mechanism is changed in the thermal reservoir, and the DBHE heat transfer capacity can effectively enhance while the quantity of geothermal water exploitation increases and the well distance decreases. However, with the change of the quantity of geothermal water exploitation, the growth rate of the DBHE heat transfer capacity reduces and the sensitivity of the change of the typical parameters on the DBHE heat transfer performance reduces.
Performance and Economic Analysis of Bubble Column Humidification and Thermoelectric Cooler Dehumidification Water Desalination System
Authors: Patel Vivek , Patel Rajesh , Kumar Sumit
Published: September 2021

Although water is one of the key elements on the globe and accessible in a large amount, nearly one-half of the people of the globe are suffering from a shortage of freshwater that is increasing at a frightening rate, most exclusively in growing nations where commercial water shortages prevail. So, in the regions with ample saline water and solar radiation where freshwater is usually limited, the humidification-dehumidification (H-DH) desalination systems have demonstrated inspiring outcomes. The experimental, theoretical, and economical analysis of the bubble column (BC) humidifier, thermoelectric cooler (TEC) based dehumidifier H-DH system has been presented in this work. The effect of various operational parameters on H-DH systems like Ta, Tw, H, do, and ya has been studied. The daily experimental and theoretical productivity obtained during the analysis of the H-DH system was in the span of 7–13 L/day and 9.1–12.4 L/day, respectively, for dissimilar functional variables while the greatest experimental and theoretical productivity was reported 12.97 L/day and 12.4 L/day, respectively, for do = 2 mm, ya = 0.016 kg/s, Tw = 60 °C, Ta = 27 °C, and H = 7 cm. Also, the experimental results present a fine confirmation with the results of the proposed mathematical model. From the economic analysis, it is found that the yearly price per liter and the payback period of the H-DH system are Rs. 5.1/L and 2.4 years, respectively, which is a very promising value.
Heat Transfer Coefficient Distribution of W and Broken W Turbulators at High Reynolds Numbers
Authors: Ghazi-Hesami Sam , Wise Dylan , Taylor Keith , Robert Étienne , Ireland Peter
Published: September 2021

An experimental and numerical study of the convective heat transfer enhancement provided by two rib families (W and Broken W) is presented, covering Reynolds numbers (Re) between 300,000 and 900,000 in a straight channel with a rectangular cross section (AR = 1.29). These high Reynolds numbers were selected for the current study since most data in the available literature typically pertain to investigations at lower Reynolds numbers. The objective of this study is to assess the local heat transfer coefficient (HTC) enhancement (compared with a smooth channel) and the overall thermal performance, taking into account the effect of increased roughness on the friction factor, of a group of W-shaped turbulators over a wide range of Reynolds numbers. Furthermore, the effects of increasing the rib spacing on the thermal performance of the Broken W configuration are presented and discussed. The numerical results are compared against heat transfer measurements obtained using the transient liquid crystal (TLC) method. The research shows that for the Broken W turbulators, increasing the Reynolds number is associated with an overall decrease of the thermal performance while the thermal performance of the W configuration is relatively insensitive to Reynolds number. Nevertheless, the Broken W configuration delivers higher thermal performance and heat transfer compared with the W configuration for the range of Re investigated. The Broken W configuration with a pitch spacing of 10 times the rib height was shown to provide the optimal thermal performance in the configurations investigated here.
Heat Transfer and Pressure Drop of an Angled Discrete Turbulator at Elevated Reynolds Numbers Up to 900,000
Authors: Ghazi-Hesami Sam , Wise Dylan , Taylor Keith , Ireland Peter , Robert Étienne
Published: September 2021

Turbulators are a promising avenue to enhance heat transfer in a wide variety of applications. An experimental and numerical investigation of heat transfer and pressure drop of a broken V (chevron) turbulator is presented at Reynolds numbers ranging from approximately 300,000 to 900,000 in a rectangular channel with an aspect ratio (width/height) of 1.29. The rib height is 3% of the channel hydraulic diameter, while the rib spacing to rib height ratio is fixed at 10. Heat transfer measurements are performed on the flat surface between ribs using transient liquid crystal (LC) thermography. The experimental results reveal a significant increase of the heat transfer and friction factor of the ribbed surface compared with a smooth channel. Both parameters increase with Reynolds number, with a heat transfer enhancement ratio of up to 2.15 (relative to a smooth channel) and a friction factor ratio of up to 6.32 over the investigated Reynolds number range. Complementary computational fluid dynamics (CFD) Reynolds-averaged Navier–Stokes (RANS) simulations are performed with the κ-ω shear-stress transport (SST) turbulence model in ansys fluent® 17.1, and the numerical estimates are compared against the experimental data. The results reveal that the discrepancy between the experimentally measured area-averaged Nusselt number and the numerical estimates increases from approximately 3% to 13% with increasing Reynolds number from 339,000 to 917,000. The numerical estimates indicate turbulators enhance heat transfer by interrupting the boundary layer as well as increasing near surface turbulent kinetic energy (TKE) and mixing.
Impact of Swirling Entropy Waves on a High Pressure Turbine
Authors: Notaristefano Andrea , Gaetani Paolo
Published: September 2021

The harsh environment exiting modern gas turbine combustion chamber is characterized by vorticity and temperature perturbations, the latter commonly referred as entropy waves. The interaction of these unsteadiness with the first turbine stage causes non-negligible effects on the aerodynamic performance, blade cooling, and noise production. The first of these drawbacks is addressed in this paper by means of an experimental campaign: entropy waves and swirl profile are injected upstream of an axial turbine stage through a novel combustor simulator. Two injection positions and different inlet conditions are considered. Steady and unsteady experimental measurements are carried out through the stage to address the combustor-turbine interaction characterizing the injected disturbance, the nozzle, and rotor outlet aerothermal field. The experimental outcomes show a severe reduction of the temperature perturbation already at stator outlet. The generated swirl profile influences significantly the aerodynamic, as it interacts with the stator and rotor secondary flows and wakes. Furthermore, the clocking position changes the region most affected by the disturbance, showing a potential modifying the injection position to minimize the entropy wave and swirl profile impact on the stage. Finally, this work shows that in order to proficiently study entropy waves, the unsteady aerodynamic flow field stator downstream has to be addressed.
Study on the Vertical Ultrasonic Vibration-Assisted Nanomachining Process on Single-Crystal Silicon
Authors: Wang Jiqiang , Geng Yanquan , Li Zihan , Yan Yongda , Luo Xichun , Fan Pengfei
Published: September 2021

Subsurface damage that is caused by mechanical machining is a major impediment to the widespread use of hard–brittle materials. Ultrasonic vibration-assisted macro- or micromachining could facilitate shallow subsurface damage compared with conventional machining. However, the subsurface damage that was induced by ultrasonic vibration-assisted nanomachining on hard–brittle silicon crystal has not yet been thoroughly investigated. In this study, we used a tip-based ultrasonic vibration-assisted nanoscratch approach to machine nanochannels on single-crystal silicon, to investigate the subsurface damage mechanism of the hard–brittle material during ductile machining. The material removal state, morphology, and dimensions of the nanochannel, and the effect of subsurface damage on the scratch outcomes were studied. The materials were expelled in rubbing, plowing, and cutting mode in sequence with an increasing applied normal load, and the silicon was significantly harder than the pristine material after plastic deformation. Transmission electron microscope analysis of the subsurface demonstrated that ultrasonic vibration-assisted nanoscratching led to larger subsurface damage compared with static scratching. The transmission electron microscopy results agreed with the Raman spectroscopy and molecular dynamic simulation. Our findings are important for instructing ultrasonic vibration-assisted machining of hard–brittle materials at the nanoscale level.
Reflecting on lived experience: Suicide prevention and the importance of social work in mental health
Authors: Ali Behiye , Staniforth Barbara , Adamson Carole
Published: September 2021

INTRODUCTION: National suicide prevention strategies and action plans have, historically, been written without input from consumers/current users of mental health services. People who could arguably be seen as experts in this area are rarely asked for their knowledge regarding the efficacy of suicide prevention and intervention efforts. The aims of this study were to gain further insight into the effectiveness of suicide prevention intervention in Aotearoa New Zealand by asking service users “What works?” and to promote lived experience as a valid form of evidence. This article focuses on the importance of a holistic model of health and wellbeing and highlights the role played by social workers, both currently and in the future, regarding suicide prevention and intervention efforts.METHODS: Twenty semi-structured interviews were conducted with individuals with lived experience of suicidal ideation and/or attempt.FINDINGS: Using thematic analysis, a variety of interventions were identified which participants found effective, including exercise, addressing physical health needs, practising mindfulness, use of medications and spirituality. These interventions, and others, are presented as themes within a framework of people, body, mind and spirit.CONCLUSIONS: It is important to view health holistically, and social workers can make an important contribution towards wellbeing through the provision of psychosocial interventions. Also, it is crucial to involve individuals with lived experience within research that informs policy and practice, and within collaborative treatment decisions.
Cessation strategies used successfully by individuals in recovery from methamphetamine addiction
Authors: Gordon Yvonne , Stephens Christine
Published: September 2021

INTRODUCTION: Methamphetamine (MA) misuse is a recognised health issue in Aotearoa New Zealand, and there is a lack of appropriate treatment available for individuals who are methamphetamine dependent. This exploratory study, undertaken in 2019, sought to gain insight from individuals in Aotearoa who have experienced MA dependence and now identify as being in recovery, to discover which strategies, approaches or treatment appeared helpful in their recovery.METHODS: The participants in the study were seven adults (New Zealand European, Samoan and Māori ethnicity) who had abstained from methamphetamine for six months or more. In-depth interviews were audiotaped and transcribed before being analysed. The data were analysed using interpretative phenomenological analysis, which has its theoretical origins in phenomenology and hermeneutics.FINDINGS: Four themes emerged to describe the lived experience of recovery from methamphetamine misuse: Getting Away, Support, Personal Sources of Strength, and Treatment. Each theme held importance in the participants’ recovery from MA and provided insight into their journey in abstaining and being in recovery.CONCLUSIONS: These findings may be used to assist others entering recovery. The present findings are limited by the size of the sample; however, they provide valuable information on this important health issue as a basis for further research, which is urgently needed in Aotearoa.
R.D. Laing’s The Divided Self: An Existential Study of Sanity and Madness (1965)
Authors: Ferguson Iain
Published: September 2021

Classic book review
“They feel like it’s all based around the offender”: Professionals explore how victim participation in family group conferences can be enhanced
Authors: Williams Tracy , Ioane Julia
Published: September 2021

INTRODUCTION: The Family Group Conference (FGC) is one of Aotearoa New Zealand’s most innovative features to emerge in the Oranga Tamariki Act (1989). It was designed to address the harm caused by youth offending, as well as set the scene for reconciliation to allow victims to heal. However, victim participation at such conferences remains low.METHODS: This study focused on a 6-month pilot project in 2019 between the agencies of New Zealand Police, Oranga Tamariki and Victim Support, that aimed to increase victim participation at FGCs within the Tāmaki Makaurau (Auckland) area. Rates of victim participation were tracked and six professionals were interviewed for their observations on the pilot.FINDINGS: Victim participation in FGCs increased during the project and interviewees identified that there had been more collaborative efforts between the professionals involved. Thematic analysis highlighted issues with 1) Agency processes and systems (with more training and resources needed, and more streamlined processes between the three agencies called for); 2) Information (youth justice information and cases were “too complicated,” and tended to be offender-focused, not necessarily understanding victim’s perspectives nor getting feedback from them); and 3) Timing (improved processes were needed around timely police referrals and there were effects of timeframes overall on victim participation).CONCLUSIONS: Participants recommended building on this exploratory pilot to increase and maintain better outcomes. The importance of victims being well-prepared for FGCs, feeling well-supported in making an in-person submission, in culturally appropriate ways, needs timely collaboration between well-trained and well-resourced professionals from the agencies involved.
At home: Field education during lockdown
Authors: Cox Yesse , McKenzie David , Powell-Grub Bronwyn , McCafferty Liz
Published: September 2021

Field education during the 2020 Aotearoa New Zealand Covid-19 lockdown was a new experience for social work educators and students alike. This case study captures the experience of one social work student during this time while on placement at the Salvation Army. Included in the account are the perspectives of the Community Ministries Manager, the placement supervisor and the placement field coordinator. Due to the Covid-19 restrictions, the student undertook the placement while at home. A pandemic can offer students opportunities to learn about managing difficult situations. Reflection on the experience provided insight into what helped and what could have been done differently. Regular debriefing, supervision and a post- crisis debrief were all important elements that aided the learning and supported the wellbeing of the student.
Effect of O2 plasma exposure time during atomic layer deposition of amorphous gallium oxide
Authors: Kröncke Hanno , Maudet Florian , Banerjee Sourish , Albert Jürgen , Wiesner Sven , Deshpande Veeresh , Dubourdieu Catherine
Published: September 2021

Amorphous gallium oxide thin films were grown by plasma-enhanced atomic layer deposition on (100) silicon substrates from trimethylgallium Ga(CH3)3 precursor and oxygen plasma. At 200 °C, the growth per cycle is in the range of 0.65–0.70 Å for O2 plasma exposure times ranging from 3 up to 30 s during each cycle. The effect of O2 plasma exposure times on the interfacial SiOx regrowth and the electrical properties was investigated. In situ spectroscopic ellipsometry shows that the SiOx regrowth occurs during the first three cycles and is limited to 0.27 nm for plasma times as long as 30 s. Increasing the O2 plasma exposure during each ALD cycle leads to a drastic decrease in the leakage current density (more than 5 orders of magnitude for 30 nm films), which is linked to the suppression of oxygen vacancy states as evidenced by spectroscopic ellipsometry. Interestingly, an increase in the dielectric constant with increasing O2 plasma exposure time is observed, reaching a value of εr∼14.2, larger than that of single crystalline β-Ga2O3. This study highlights the crucial role of oxygen plasma exposure time in the control and tuning of the electrical properties of amorphous gallium oxide films.
Clinical Estimation of the Use of the Hip and Knee Extensors During Athletic Movements Using 2D Video
Authors: Straub Rachel K. , Horgan Alex , Powers Christopher M.
Published: September 2021

Given that increased use of the knee extensors relative to the hip extensors may contribute to various knee injuries, there is a need for a practical method to characterize movement behavior indicative of how individuals utilize the hip and knee extensors during dynamic tasks. The purpose of the current study was to determine whether the difference between sagittal plane trunk and tibia orientations obtained from 2D video (2D trunk–tibia) could be used to predict the average hip/knee extensor moment ratio during athletic movements. Thirty-nine healthy athletes (15 males and 24 females) performed 6 tasks (step down, drop jump, lateral shuffle, deceleration, triple hop, and side-step-cut). Lower-extremity kinetics (3D) and sagittal plane video (2D) were collected simultaneously. Linear regression analysis was performed to determine if the 2D trunk–tibia angle at peak knee flexion predicted the average hip/knee extensor moment ratio during the deceleration phase of each task. For each task, an increase in the 2D trunk–tibia angle predicted an increase in the average hip/knee extensor moment ratio when adjusted for body mass (all P < .013, R2 = .17–.77). The 2D trunk–tibia angle represents a practical method to characterize movement behavior that is indicative of how individuals utilize the hip and knee extensors during dynamic tasks.
What Are the Benefits of Hosting a Sporting Mega Event? Evidence From Industrial Firms in China
Authors: Hayduk Ted , Rewilak Johan
Published: September 2021

It is acknowledged that the economic benefits of hosting a sporting mega event are overestimated and/or short lived. However, many studies neglect the impact of the industrial sector, preferring to focus on service sector activity. It is further claimed that hosting a sporting mega event funnels a nation’s resources into one specific region at the expense of others. Therefore, this article empirically investigates whether industrial firms in Beijing disproportionately (a) increased their invested capital ahead of the 2008 Olympic Games and (b) became more profitable after the Games relative to similar firms from comparable Chinese nonhost cities. Using a difference-in-difference estimation strategy, the authors find no disproportionate impact of the Olympic Games on Beijing firms’ invested capital or profitability.
Florigen sequestration in cellular membranes modulates temperature-responsive flowering
Authors: Susila Hendry , Jurić Snježana , Liu Lu , Gawarecka Katarzyna , Chung Kyung Sook , Jin Suhyun , Kim Soo-Jin , Nasim Zeeshan , Youn Geummin , Suh Mi Chung , Yu Hao , Ahn Ji Hoon
Published: September 2021

Linking flowering to ambient temperature

In the small mustard plant
Arabidopsis
, the florigen FLOWERING LOCUS T (FT) mobilizes to initiate flowering at the shoot apical meristem. Susila
et al
. now show that FT, which is produced in leaf cells, can be held in reserve if ambient temperatures are not favorable (see the Perspective by Jaillais and Parcy). At low temperatures, FT binds a membrane phosopholipid and is thus restricted in mobility. At higher temperatures, such binding is less favored, and FT is released to mobilize into the shoot apical meristem to drive flowering. Thus, temperature-sensitive lipid binding helps the plant time flowering with favorable ambient temperatures. —PJH
Plasmonic topological metasurface by encircling an exceptional point
Authors: Song Qinghua , Odeh Mutasem , Zúñiga-Pérez Jesús , Kanté Boubacar , Genevet Patrice
Published: September 2021

Upon reflection, modulate phase

Metasurfaces provide a platform to fabricate optical devices in a compact form much thinner than their corresponding bulk optical components. Recognizing that metasurfaces are also open systems interacting with their environment, Song
et al
. designed a metasurface that exploits those non-Hermitian properties such that they can encircle an exceptional point. Subsequent scattering from such an exceptional point was shown to be polarization dependent, thus providing an additional control knob in designing metasurfaces for wave front engineering. —ISO
Enabling oncogenes
Authors: Vredevoogd David W. , Peeper Daniel S.
Published: September 2021

Melanoma can arise only from cells with a permissive chromatin landscape
Lipid-mediated regulation of flowering time
Authors: Jaillais Yvon , Parcy François
Published: September 2021

An anionic phospholipid tells plants when to flower according to ambient temperature
The will to fight
Authors: Atran Scott
Published: September 2021

As the Taliban rapidly crushed US-backed Afghan forces, many politicians, pundits, and military leaders expressed surprise at having overestimated an ally’s will to fight and underestimated the enemy’s. Similarly in 2014, after the Islamic State (ISIS) routed US-backed Iraqi forces, President Obama endorsed the intelligence assessment that “predicting the will to fight…is an imponderable.” That attitude reflects political and military leaders’ continual discounting of research, supported and known by many of those leaders, on the importance of sacred values and spiritual strength to the will to fight. It may remain “imponderable”—and attendant security challenges seemingly intractable—so long as it continues to be viewed through a narrow lens of instrumental, utilitarian rationality.
The hunt for SARS-CoV-2’s ancestors heats up
Authors: Cohen Jon
Published: September 2021

Cousins of the pandemic virus in animals help chart the path to humans
Confederate ties knock ocean science pioneer from pedestals
Authors: Voosen Paul
Published: September 2021

Institutions move to drop Matthew Fontaine Maury’s name
Adaptive immune determinants of viral clearance and protection in mouse models of SARS-CoV-2
Authors: Israelow Benjamin , Mao Tianyang , Klein Jonathan , Song Eric , Menasche Bridget , Omer Saad B. , Iwasaki Akiko
Published: September 2021

In a mouse model, protective immunity to SARS-CoV-2 following vaccination or recovery is primarily mediated by the antibody response.
Mutual gaze with a robot affects human neural activity and delays decision-making processes
Authors: Belkaid Marwen , Kompatsiari Kyveli , De Tommaso Davide , Zablith Ingrid , Wykowska Agnieszka
Published: September 2021

Task-irrelevant robot gaze evokes neural suppression, delays decisions, and alters social decision-making strategies.
A role for lipid transporters in PDAC
Authors: Baek Amy E.
Published: September 2021

ApoE mediates immune suppression in pancreatic ductal adenocarcinoma.
Engineered nasal cartilage for the repair of osteoarthritic knee cartilage defects
Authors: Acevedo Rua Lina , Mumme Marcus , Manferdini Cristina , Darwiche Salim , Khalil Ahmad , Hilpert Morgane , Buchner David A. , Lisignoli Gina , Occhetta Paola , von Rechenberg Brigitte , Haug Martin , Schaefer Dirk J. , Jakob Marcel , Caplan Arnold , Martin Ivan , Barbero Andrea , Pelttari Karoliina
Published: September 2021

Nasal chondrocyte–based grafts modulate osteoarthritis-like conditions in animal models and improve life quality in patients with knee osteoarthritis.
4-Aminopyridine is a promising treatment option for patients with gain-of-function
KCNA2
-encephalopathy
Authors: Hedrich Ulrike B. S. , Lauxmann Stephan , Wolff Markus , Synofzik Matthis , Bast Thomas , Binelli Adrian , Serratosa José M. , Martínez-Ulloa Pedro , Allen Nicholas M. , King Mary D. , Gorman Kathleen M. , Zeev Bruria Ben , Tzadok Michal , Wong-Kisiel Lily , Marjanovic Dragan , Rubboli Guido , Sisodiya Sanjay M. , Lutz Florian , Ashraf Harshad Pannikkaveettil , Torge Kirsten , Yan Pu , Bosselmann Christian , Schwarz Niklas , Fudali Monika , Lerche Holger
Published: September 2021

4-Aminopyridine is a potential therapeutic option for a subgroup of patients with
KCNA2
-encephalopathy and gain-of-function variants.
Draft Genome Sequence of Enterobacter asburiae NCR1, a Plant Growth-Promoting Rhizobacterium Isolated from a Cadmium-Contaminated Environment
Authors: François Charlotte J. , Batinovic Steven , Petrovski Steve , Gendall Anthony R.
Published: September 2021

Enterobacter asburiae
NCR1 is a plant growth-promoting rhizobacterium isolated from the rhizosphere of
Carpobrotus rossii
. We report the draft genome sequence of
E. asburiae
strain NCR1, which revealed many genes facilitating beneficial interactions with plant hosts.
Genome Sequence of Staphylococcus aureus Strain PS/BAC/317/16/W, Isolated from Contaminated Platelet Concentrates in England
Authors: Yousuf Basit , Flint Annika , Weedmark Kelly , McDonald Carl , Bearne Jennifer , Pagotto Franco , Ramirez-Arcos Sandra
Published: September 2021

We present the genome sequence of
Staphylococcus aureus
strain PS/BAC/317/16/W, which was isolated from contaminated platelet concentrates by the National Health Service Blood and Transplant in England (2017). Genome sequence analysis revealed the presence of one chromosome (2,665,983 bp) and two plasmids (4,265 bp and 2,921 bp) in this strain.
Genome Sequence of Acinetobacter towneri Strain DSM 16313, Previously Known as the Proposed Type Strain of Acinetobacter seohaensis
Authors: Maehana Shotaro , Kitasato Hidero , Suzuki Masato
Published: September 2021

Acinetobacter
species are widely distributed in the environment and clinical settings worldwide. We report the 2.99-Mbp draft genome sequence of
Acinetobacter towneri
strain DSM 16313, which was isolated from seawater in South Korea and proposed as a type strain of
Acinetobacter seohaensis
. Genome comparisons demonstrated that
A. seohaensis
should be reclassified as
A. towneri
.
School academic performance of children hospitalised with a chronic condition
Authors: Hu Nan , Fardell Joanna , Wakefield Claire E , Marshall Glenn M , Bell Jane C , Nassar Natasha , Lingam Raghu
Published: September 2021

Objective

To examine academic outcomes among children hospitalised with a chronic health condition.

Design

Population-level birth cohort.

Setting

New South Wales, Australia.

Participants

397 169 children born 2000–2006 followed up to 2014.

Intervention/exposure

Hospitalisations with a chronic condition.

Main outcome measures

Academic underperformance was identified as ‘below the national minimum standard’ (BNMS) in five literacy/numeracy domains using the national assessment (National Assessment Program-Literacy and Numeracy) data. Multivariable logistic regression assessed the adjusted ORs (aORs) of children performing BNMS in each domain at each grade (grades 3, 5 and 7, respectively).

Results

Of children hospitalised with a chronic condition prior to National Assessment Program-Literacy and Numeracy (NAPLAN) (16%–18%), 9%–12% missed ≥1 test, with a maximum of 37% of those hospitalised ≥7 times, compared with 4%–5% of children not hospitalised. Excluding children who missed a NAPLAN test, more children hospitalised with a chronic condition performed BNMS across all domains and grades, compared with children not hospitalised (eg, for BNMS in reading at grade 3: n=2588, aOR 1.35 (95% CI 1.28 to 1.42); for BNMS in numeracy at grade 3: n=2619, aOR 1.51 (95% CI 1.43 to 1.59)). Increasing frequency and bed-days of hospitalisation were associated with 2–3 fold increased odds of performing BNMS across all domains and grades. Children hospitalised with mental health/behavioural conditions had the highest odds of performing BNMS across all domains at each grade.

Conclusions

Children hospitalised with a chronic condition underperform academically across literacy/numeracy domains at each school grade. Health and educational supports are needed to improve these children’s academic outcomes.
Patchy signals: capturing women’s voices in mobile phone surveys of rural India
Authors: Hersh Skye , Nair Divya , Komaragiri Pradyot Bharadwaj , Adlakha Raghav Kapoor
Published: September 2021

Phone surveys are a rapid and cost-effective way to collect primary data for research, monitoring and evaluation purposes. But for these data to be precise, reliable and unbiased, women’s perspectives must be accurately represented. Throughout 2020, we conducted seven household surveys in rural India to understand households’ experiences of the COVID-19 pandemic and contemporaneous relief programmes. Given social distancing protocols, we conducted these surveys over the phone, using household phone numbers collected during earlier, face-to-face research. Analysing metadata from these surveys (along with women’s responses to questions about phone use), we determine how gaps in phone access inhibit women’s representation in phone surveys. We find that the prevalence of male management of household phones significantly reduces access to female respondents. This is a problem for two reasons. Firstly, men are usually the first to pick up the phone: in two surveys in which we tracked the gender of the person who picked up, men picked up 63.2% and 71.1% of the time, respectively. Moreover, only a small minority of those we reached by phone were able and willing to pass the phone to a household member of the opposite gender, when prompted (with no statistically significant difference between pass rates for women and men). This low immediate pass rate, in combination with low female pickup, led to fewer women respondents. As such, we recommend that researchers dedicate time and resources to taking appointments and making call-backs to reach more women. We also show that the use of female enumerators improves households’ willingness to participate in women-centred surveys, and call for more investment into female enumerator teams.
Outcomes of endovascular thrombectomy in patients selected by computed tomography perfusion imaging – a matched cohort study comparing nonagenarians to younger patients
Authors: Rahangdale Rahul , Hackett Christopher Todd , Cerejo Russell , Fuller Nicholas M , Malhotra Konark , Williamson Richard , Hentosz Terry , Tayal Ashis H , Rana Sandeep S
Published: September 2021

Background

Endovascular thrombectomy (EVT) is efficacious for appropriately selected patients with large vessel occlusions (LVO) up to 24 hours from symptom onset. There is limited information on outcomes of nonagenarians, selected with computed tomography perfusion (CTP) imaging.

Methods

We retrospectively analyzed data from a large academic hospital between December 2017 and October 2019. Patients receiving EVT for anterior circulation LVO were stratified into nonagenarian (≥90 years) and younger (<90 years) groups. We performed propensity score matching on 18 covariates. In the matched cohort we compared: primary outcome of inpatient mortality and secondary outcomes of successful reperfusion (TICI ≥2B), symptomatic intracranial hemorrhage (sICH), and functional independence. Subgroup analysis compared CTP predicted core volumes in nonagenarians with outcomes.

Results

Overall, 214 consecutive patients (26 nonagenarians, 188 younger) underwent EVT. Nonagenarians were aged 92.8±2.9 years and younger patients were 74.5±13.5 years. Mortality rate was significantly greater in nonagenarians compared with younger patients (43.5% vs 10.4%, OR 9.33, 95% CI 2.88 to 47.97, P<0.0001) and a greater proportion of nonagenarians developed sICH (13.0% vs 3.0%, OR 6.00, 95% CI 1.34 to 55.20, P=0.02). There were no significant differences for successful reperfusion (P=1.00) or functional independence (P=0.75). Nonagenarians selected with smaller ischemic core volumes had decreased mortality rates (P=0.045).

Conclusions

Nonagenarians were noted to have greater mortality and sICH rates following EVT compared with matched younger patients, which may be ameliorated by selecting patients with smaller CTP core volumes. Nonagenarians undergoing EVT had similar rates of successful reperfusion and functional independence compared with the younger cohort.
Follow-up of intra-arterial delivery of bevacizumab for treatment of butterfly glioblastoma in patient with first-in-human, real-time MRI-guided intra-arterial neurointervention
Authors: Zawadzki Michal , Walecki Jerzy , Kostkiewicz Boguslaw , Kostyra Kacper , Walczak Piotr , Janowski Miroslaw
Published: September 2021

This case report shows that real-time MRI may aid in the precision of intra-arterial delivery of bevacizumab to butterfly glioblastoma. Fast clinical improvement, decrease of contrast enhancing status, and no serious adverse effects were observed at discharge from hospital. The patient regained pre-recurrent neurological status for 2 months with a subsequent fast clinical decline and an increase in tumor volume. The patient underwent a second procedure of intra-arterial delivery of bevacizumab to the brain, with substantial clinical and radiological improvement, but not the level of improvement observed after the first procedure. Another clinical decline occurred with an increase in tumor size and the patient was treated 2 months later with a third intra-arterial infusion of bevacizumab. While another positive effect was achieved, it was less pronounced than before, and the patient died 1.5 months later. There were no technical, ischemic or other complications during the procedures. The patient survived 218 days from the first symptoms of tumor recurrence, 190 days from the first MRI, and 175 days from the first intra-arterial treatment of bevacizumab.
General anesthesia during endovascular therapy for acute ischemic stroke: benefits beyond better reperfusion?
Authors: Simonsen Claus Z , Rasmussen Mads , Schönenberger Silvia , Hendén Pia Löwhagen , Bösel Julian , Valentin Jan Brink
Published: September 2021

Background

Endovascular therapy (EVT) is standard of care for stroke caused by large vessel occlusion. Whether EVT should be performed under general anesthesia (GA) or conscious sedation (CS) is controversial. While a meta-analysis of randomized trials showed better outcome for EVT under GA, observational studies suggested the opposite. A proposed advantage of GA is better reperfusion achieved via more successful handling of the immobile patient. The aim of this study was to investigate if the good outcome seen in patients treated under GA was mediated by better reperfusion.

Methods

The meta-analysis included 368 individual patients from three randomized controlled trials, of whom 185 patients were randomized to CS. A mediator analysis was performed to examine if the better outcome in the GA arm was driven by higher reperfusion rate.

Results

The total effect showed a risk difference (RD) of 0.15 (95% CI 0.04 to 0.25), associating GA with a beneficial outcome. The direct effect of GA constituted a large portion, with an RD of 0.12 (95% CI 0.01 to 0.22), while only a small portion was mediated through the degree of reperfusion, with an RD of 0.03 (95% CI 0.02 to 0.04).

Conclusion

The better outcome after EVT in the GA arm was mainly a direct effect—that is, an effect that was not explained by better reperfusion. We also found a better outcome in the GA arm when reperfusion was not achieved. Whether this is an effect of the stable condition and blood pressure under GA or a neuroprotective effect will need to be investigated in future research.
Transcarotid artery revascularization (TCAR): a technical video
Authors: Sujijantarat Nanthiya , Antonios Joseph , Koo Andrew , Renedo Daniela , Cord Branden J , Zetchi Akli , Hebert Ryan , Matouk Charles
Published: September 2021

Carotid revascularization is an important method of stroke prevention and includes carotid endarterectomy and transfemoral carotid angioplasty and stenting. More recently, a hybrid open-endovascular approach, termed transcarotid artery revascularization (TCAR), is garnering increased attention. Although fundamentally a ‘stenting procedure’, unlike transfemoral carotid angioplasty and stenting, TCAR allows for a proximal neuroprotection strategy based on flow reversal. In this technical video, we will review operative techniques and nuances of the TCAR procedure, with a particular focus on the neurovascular proceduralist looking to adopt this technique into routine clinical practice(video 1).

Video 1

TCAR Technical Video
Four-level double V-type atomic system solved by virtue of supersymmetric unitary transformation
Authors: Abd El-Wahab N. H. , Zait R. A.
Published: September 2021

We consider a four-level double V-type atom with two closely-separated top levels and two closely-separated lower levels interacting with a single mode field via multi-photon processes and in the presence of Kerr medium. We show that this atomic system possesses supersymmetric structure and construct its supersymmetric generators. We diagonalize the Hamiltonian of this system using supersymmetric unitary transformation and obtain the corresponding eigenstates and eigenvalues. The atom–field wave functions are obtained when the atom and the field mode are initially in two different cases. The evolution of both the quasi-probability distribution Q-function and the Mandel Q-parameter of the field are studied when the input field is in a coherent state. The influence of the Kerr medium and the detuning parameters on the behavior of these quantum effects is analyzed. The results show that they play a prominent role on the Poissonian statistics of the field. Also, the Kerr medium changes the behavior of the quasi-probability distribution Q-function. We end with discussion and conclusions.
Type 0 ℤ2 × ℤ2 heterotic string orbifolds and misaligned supersymmetry
Authors: Faraggi Alon E. , Matyas Viktor G. , Percival Benjamin
Published: September 2021

The [Formula: see text] heterotic string orbifold yielded a large space of phenomenological three generation models and serves as a testing ground to explore how the Standard Model of particle physics may be incorporated in a theory of quantum gravity. In this paper, we explore the existence of type 0 models in this class of string compactifications. We demonstrate the existence of type 0 [Formula: see text] heterotic string orbifolds, and show that there exist a large degree of redundancy in the space of GGSO projection coefficients when the type 0 restrictions are implemented. We explore the existence of such configurations in several constructions. The first correspond to essentially a unique configuration out of a priori [Formula: see text] discrete GGSO choices. We demonstrate this uniqueness analytically, as well as by the corresponding analysis of the partition function. A wider classification is performed in [Formula: see text]-models and [Formula: see text]-models, where the first class correspond to compactifications of a tachyonic ten-dimensional heterotic string vacuum, whereas the second correspond to compactifications of the ten-dimensional nontachyonic [Formula: see text]. We show that the type 0 models in both cases contain physical tachyons at the free fermionic point in the moduli space. These vacua are therefore necessarily unstable, but may be instrumental in exploring the string dynamics in cosmological scenarios. We analyze the properties of the string one-loop amplitude. Naturally, these are divergent due to the existence of tachyonic states. We show that once the tachyonic states are removed by hand the amplitudes are finite and exhibit a form of misaligned supersymmetry.
Theoretical study of micro-structure fabrication by multi-beam laser interference lithography with different polarization combinations
Authors: Wang Xiangxian , Jia Tianxu , Zhu Jiankai , Su Yingwen , Zhang Liping , Yang Hua , Yi Zao , Qi Yunping
Published: September 2021

In this study, we systematically and comprehensively investigated the influence of polarization angle on the fabrication of micro-structures by multi-beam laser interference lithography. Using theoretical analysis and simulation, we studied the effect of different polarization combinations, i.e. transverse electric (TE) and transverse magnetic (TM) polarization combinations, on the characteristics of the micro-structures fabricated by three-, four-, and six-beam laser interference lithography. We successfully obtained micro-structures with different periodic patterns such as honeycomb dots, quasi-elliptic dots, different square dots, and quasi-triangular dots. The simulation results illustrate that polarization affects the formation of interference patterns, pattern contrasts, and periods. The methods discussed herein are simple, low cost, and allow excellent control over structural parameters, and hence are useful for the micro-structure manufacturing industry.
Synchronization and Pattern Formation in a Memristive Diffusive Neuron Model
Authors: Sharma Sanjeev Kumar , Mondal Arnab , Mondal Argha , Upadhyay Ranjit Kumar , Ma Jun
Published: September 2021

In this article, we construct an excitable memristive diffusive neuron model by considering a biophysical slow–fast bursting oscillator and study the effects of electromagnetic induction on the dynamics of the single model as well as the coupled systems. We explore various firing regimes such as tonic spiking, bursting, and mixed-mode oscillations depending on the bifurcation structure with different injected current stimuli, then perform a comparative analysis on the synchronization of the coupled oscillators by setting the model into two different network architectures. First, a diffusively coupled network is considered, and later a global network is constructed. The results suggest that the diffusively connected neurons show complete synchronization at higher couplings for bursting and tonic spiking regimes. Furthermore, we show that the extended spatial system can generate spiral-like patterns in the vicinity of a Hopf bifurcation point and observe the impact of Gaussian white noise to study its effects on pattern formation. These types of patterns are robust in the excitable model. Our results might contribute significantly to the dynamical studies of irregular neural computation.
Hidden Attractor and Multistability in a Novel Memristor-Based System Without Symmetry
Authors: Ji’e Musha , Yan Dengwei , Wang Lidan , Duan Shukai
Published: September 2021

Memristor, as a typical nonlinear element, is able to produce chaotic signals in chaotic systems easily. Chaotic systems have potential applications in secure communications, information encryption, and other fields. Therefore, it is of importance to generate abundant dynamic behaviors in a single chaotic system. In this paper, a novel memristor-based chaotic system without equilibrium points is proposed. One of the essential features is the absence of symmetry in this system, which increases the complexity of the new system. Then, the nonlinear dynamic behaviors of the system are analyzed in terms of chaos diagrams, bifurcation diagrams, Poincaré maps, Lyapunov exponent spectra, the sum of Lyapunov exponents, phase portraits, 0–1 test, recurrence analysis and instantaneous phase. The results of the sum of Lyapunov exponents show that the given system is a quasi-Hamiltonian system with certain initial conditions (IC) and parameters. Next, other critical phenomena, such as hidden multi-scroll attractors, abundant coexistence characteristics, are found characterized through basins of attraction and others. Especially, it reveals some rare phenomena in other systems that multiple hidden hyperchaotic attractors coexist. Finally, the circuit implementation based on Micro Control Unit (MCU) confirms theoretical analysis and the numerical simulation.
Bounds on the Steiner–Wiener index of graphs
Authors: Rasila V. A. , Vijayakumar Ambat
Published: September 2021

Let S be a set of vertices of a connected graph G. The Steiner distance of S is the minimum size among all connected subgraphs of G containing the vertices of S. The sum of all Steiner distances on sets of size k is called the Steiner k-Wiener index. We obtain formulae for bounds on the Steiner–Wiener index of graphs in terms of chromatic number, vertex connectivity and independence number. Also, we obtain bounds for 4-cycle free graphs.
What Happens When Robots Punish? Evaluating Human Task Performance During Robot-Initiated Punishment
Authors: Jois Himavath , Wagner Alan R.
Published: September 2021

This article examines how people respond to robot-administered verbal and physical punishments. Human participants were tasked with sorting colored chips under time pressure and were punished by a robot when they made mistakes, such as inaccurate sorting or sorting too slowly. Participants were either punished verbally by being told to stop sorting for a fixed time, or physically, by restraining their ability to sort with an in-house crafted robotic exoskeleton. Either a human experimenter or the robot exoskeleton administered punishments, with participant task performance and subjective perceptions of their interaction with the robot recorded. The results indicate that participants made more mistakes on the task when under the threat of robot-administered punishment. Participants also tended to comply with robot-administered punishments at a lesser rate than human-administered punishments, which suggests that humans may not afford a robot the social authority to administer punishments. This study also contributes to our understanding of compliance with a robot and whether people accept a robot’s authority to punish. The results may influence the design of robots placed in authoritative roles and promote discussion of the ethical ramifications of robot-administered punishment.