bluuebunny/crossref_metadata_2025 huggingface dataset:
Clinico-pathological features of diabetic and non-diabetic renal diseases in type 2 diabetic patients: a retrospective study from a 10-year experience in a single center
Authors: Sun Yuemeng , Ren Yawei , Lan Ping , Yu Xiaoyang , Feng Jie , Hao Dapeng , Xie Liyi
Published: March 2023

Aim

To compare clinical and pathological characteristics as well as prognosis between diabetic nephropathy (DN) and non-diabetic renal disease (NDRD) so as to explore potential diagnostic criteria of DN and provide some guidance for the treatment of type 2 diabetes mellitus (T2DM) patients with kidney involvement.

Methods

T2DM patients with renal impairment who underwent kidney biopsy were included in this study, who were classified into 3 groups (DN, NDRD, DN with NDRD) based on their renal pathological diagnosis. Baseline clinical characteristics as well as follow-up data were collected and analyzed among 3 groups. Logistic regression was performed to determine the best predictors for DN diagnosis. Additional 34 MN patients without diabetes were enrolled by propensity score matching method to compare serum PLA2R antibody titer and kidney outcomes between diabetic MN patients and MN alone.

Results

Among 365 patients with type 2 diabetes who underwent kidney biopsy, 179 (49.0%) patients were diagnosed with NDRD alone and 37 (10.1%) patients with NDRD combined DN. Risk factors for DN development in T2DM patients were longer time since diabetes diagnosis, higher level of serum creatinine, absence of hematuria and presence of diabetic retinopathy by multivariate analysis. Lower rate of proteinuria remission and higher risk of renal progression were observed in DN group compared with NDRD group. Membranous nephropathy was the most common NDRD in diabetic patients. There was no difference in serum PLA2R antibody positiveness or titer between MN patients with or without T2DM. There was lower remission rate but similar renal progression in diabetic MN when age, gender, baseline eGFR, albuminuria and IFTA score were adjusted.

Conclusions

Non-diabetic renal disease is not uncommon in T2DM patients with renal impairment, which has better prognosis with proper treatment. Coexisting diabetic status does not exert negative impact on renal progression in MN patients, and immunosuppressive agents should be administered when necessary.
Nodulation alleviates the stress of lower water availability in Vachellia sieberiana
Authors: Telford Elizabeth M. , Stevens Nicola , Midgley Guy F. , Lehmann Caroline E. R.
Published: March 2023

The genus Vachellia (Fabaceae) has a pan-tropical distribution and numerous Vachellia species are currently observed to be expanding their indigenous ranges and/or are invasive. Most Vachellia species have the capacity to enhance nitrogen uptake via an N2-fixing rhizobial mutualism that manifests in specialized root nodule structures enabling the catalysis of atmospheric N2 into a plant useable form. Improved understanding of nodulation may provide new insight to the changing patterns of ecological success of Vachellia species. Here, we investigated how the seedling growth, allometry and nodulation of two common Vachellia species, the arid Vachellia erioloba and the mesic Vachellia sieberiana, responded to varied levels of water availability. Seedlings were grown at 4%, 8% and 16% soil moisture content (SMC) for four months. The seedling growth and allometry of V. erioloba was unresponsive to changing water availability, and no nodulation was observed. The allometry of V. sieberiana was responsive to changing water availability and nodulation was observed; with the highest nodule biomass and growth rate recorded at 4% SMC. These patterns suggest that V. erioloba does not require the rhizobial mutualism, possibly due to lower competitive interactions between woody plants and grass in the arid savanna. Whereas, due to the competitive vegetation interactions typical in the mesic savanna, N2- fixation via nodule development could provide V. sieberiana a competitive advantage over grass not only in limited N conditions, but also during periods of lower water availability.
Climate change might lead to substantial niche displacement in one of the most biodiverse regions in the world
Authors: Murakami Mariana , Batke Sven , Pie Marcio R. , Ramos Flavio
Published: March 2023

Climatic niches are key factors driving global and regional species distributions. The Atlantic Forest domain is considered one of the most threatened biomes in the world, and one of the main centres of plant diversity and endemism in the Neotropics. Of the over 13,000 species of vascular plants, nearly 15% are vascular epiphytes. Here we analysed for the first time how current epiphyte niches will be affected under future climate projections (SSP126 and SSP585) within 1.5 million km2of Atlantic Forest in South America. Using the largest database of vascular epiphytes to date (n = 1521 species; n = 75,599 occurrence records) and ordination models, we found that the Atlantic Forest is expected to become warmer and drier and that up to 304 epiphyte species (20%) will have their average niche positions displaced outside the available climate space by the years 2040–2100. The findings from this study can help to inform ongoing legislative conservation efforts in one of the world’s most biodiverse regions.
Effectiveness of clinical scores in predicting coronary artery disease in familial hypercholesterolemia: a coronary computed tomography angiography study
Authors: Catapano Federica , Galea Nicola , Pambianchi Giacomo , D’Erasmo Laura , Borrazzo Cristian , Cundari Giulia , Marchitelli Livia , Maranghi Marianna , Minicocci Ilenia , Di Costanzo Alessia , Carbone Iacopo , Francone Marco , Arca Marcello , Catalano Carlo
Published: March 2023

Purpose

One of the major challenges in the management of familial hypercholesterolemia (FH) is the stratification of cardiovascular risk in asymptomatic subjects. Our purpose is to investigate the performance of clinical scoring systems, Montreal-FH-score (MFHS), SAFEHEART risk (SAFEHEART-RE) and FH risk score (FHRS) equations and Dutch Lipid Clinic Network (DLCN) diagnostic score, in predicting extent and severity of CAD at coronary computed tomography angiography (CCTA) in asymptomatic FH.

Material and methods

One-hundred and thirty-nine asymptomatic FH subjects were prospectively enrolled to perform CCTA. MFHS, FHRS, SAFEHEART-RE and DLCN were assessed for each patient. Atherosclerotic burden scores at CCTA (Agatston score [AS], segment stenosis score [SSS]) and CAD-RADS score were calculated and compared to clinical indices.

Results

Non-obstructive CAD was found in 109 patients, while 30 patients had a CAD-RADS ≥ 3. Classifying the two groups according to AS, values varied significantly for MFHS (p < 0.001), FHRS (p < 0.001) and SAFEHEART-RE (p = 0.047), while according to SSS only MFHS and FHRS showed significant differences (p < 0.001). MFHS, FHRS and SAFEHEART-RE, but not DLCN, showed significant differences between the two CAD-RADS groups (p < .001).

MFHS proved to have the best discriminatory power (AUC = 0.819; 0.703–0.937, p < 0.001) at ROC analysis, followed by FHRS (AUC = 0.795; 0.715–0.875, p < .0001) and SAFEHEART-RE (AUC = .725; .61–.843, p < .001).

Conclusions

Greater values of MFHS, FHRS and SAFEHEART-RE are associated to higher risk of obstructive CAD and might help to select asymptomatic patients that should be referred to CCTA for secondary prevention.
The association between breast arterial calcification and atherosclerotic cardiovascular disease in an Australian population-based breast cancer case–control study
Authors: Lee Sing Ching , Pirikahu Sarah , Fritschi Lin , Boyle Terry , Schultz Carl , Wylie Elizabeth , Stone Jennifer
Published: March 2023

Purpose

Atherosclerotic cardiovascular disease (ASCVD) is a major cause of morbidity and mortality. Breast arterial calcification (BAC) on mammograms is not associated with breast cancer risk. However, there is increasing evidence supporting its association with cardiovascular disease (CVD). This study examines the association between BAC and ASCVD and their risk factors within an Australian population-based breast cancer study.

Materials and methods

Data from the controls who participated in the breast cancer environment and employment study (BCEES) were linked with the Western Australian Department of Health Hospital Morbidity database and Mortality Registry to obtain ASCVD outcomes and related risk factor data. Mammograms from participants with no prior history of ASCVD were assessed for BAC by a radiologist. Cox proportional hazards regression was used to examine the association between BAC and later occurrence of an ASCVD event. Logistic regression was used to investigate the factors associated with BAC.

Results

A total of 1020 women with a mean age of 60 (sd = 7.0 years) were included and BAC found in 184 (18.0%). Eighty (7.8%) of the 1020 participants developed ASCVD, with an average time to event of 6.2 years (sd = 4.6) from baseline. In univariate analysis, participants with BAC were more likely to have an ASCVD event (HR = 1.96 95% CI 1.29–2.99). However, after adjusting for other risk factors, this association attenuated (HR = 1.37 95% CI 0.88–2.14). Increasing age (OR = 1.15, 95% CI 1.12–1.19) and parity (pLRT < 0.001) were associated with BAC.

Conclusion

BAC is associated with increased ASCVD risk, but this is not independent of cardiovascular risk factors.
Impact of Household Interventions on Homestead Biodiversity Management and Household Livelihood Resilience: An Intertemporal Analysis from Bangladesh
Authors: Hossain Mohammad Razib , Khan Md. Akhtaruzzaman
Published: March 2023

Household livelihood preferences are crucial determinants of homestead biodiversity. Therefore, we conducted a temporal analysis (harnessing data from three different time points (i.e., 1994, 2004, and 2014) with ten years of interval starting from 1994) on three Bangladeshi subdistricts to trace the effect of managed interventions on homestead biodiversity. Our findings unravel the transformation of a non-profitable untapped homestead agrobiodiversity from 1994 into an intervened and profitable biodiversity in 2014. The domestication of the introduced species in the homesteads increased the earnings by many folds. The observed stand structure of the introduced tree species was also financially profitable in 2014. We noted that tree diversity, richness, and evenness increased in the study areas while dominance decreased. Animal diversity and evenness decreased; however, richness and dominance increased. Management interventions only occurred when households grasped that homestead biodiversity could significantly supplement their family income. Management interventions occurred in the following ways: willingness to dedicate labor for both males and females increased over time, and willingness to pay labor costs significantly increased (i.e., on average, a male and female member in Haluaghat spent 336 labor hours/year and 288 labor hour/year, which is equivalent to an investment of BDT 23,100 (USD 330) and BDT 12,240 (USD 174.9), respectively in 2014), and average annual investment for agrobiodiversity management almost tripled. As the yearly investment soared, management interventions became better planned. Consequently, earnings from agrobiodiversity increased drastically. In 2014, households in Gouripur, Ishwarganj, and Haluaghat received 43.2, 34.5, and 39.3% of their total income from homestead biodiversity, which generated 157.8, 125.7, and 143.2 person-days employment/household. Thus, planned investment in homestead biodiversity management provides upgraded ecosystem services. Therefore, we claim that intervention is not always wrong, and planned interventions can lead to a progressing symbiotic relationship (a win–win situation) between households and homestead biodiversity.
Current collectors based on multiwalled carbon-nanotubes and few-layer graphene for enhancing the conversion process in scalable lithium-sulfur battery
Authors: Marangon Vittorio , Barcaro Edoardo , Minnetti Luca , Brehm Wolfgang , Bonaccorso Francesco , Pellegrini Vittorio , Hassoun Jusef
Published: March 2023

We investigated herein the morphological, structural, and electrochemical features of electrodes using a sulfur (S)-super P carbon (SPC) composite (i.e., S@SPC-73), and including few-layer graphene (FLG), multiwalled carbon nanotubes (MWCNTs), or a mixture of them within the current collector design. Furthermore, we studied the effect of two different electron-conducting agents, that is, SPC and FLG, used in the slurry for the electrode preparation. The supports have high structural crystallinity, while their morphologies are dependent on the type of material used. Cyclic voltammetry (CV) shows a reversible and stable conversion reaction between Li and S with an activation process upon the first cycle leading to the decrease of cell polarization. This activation process is verified by electrochemical impedance spectroscopy (EIS) with a decrease of the resistance after the first CV scan. Furthermore, CV at increasing scan rates indicates a Li+diffusion coefficient (D) ranging between 10−9and 10−7cm2·s−1in the various states of charge of the cell, and the highestDvalue for the electrodes using FLG as electron-conducting agent. Galvanostatic tests performed at constant current of C/5 (1 C = 1675 mA·gS−1) show high initial specific capacity values, which decrease during the initial cycles due to a partial loss of the active material, and subsequently increase due to the activation process. All the electrodes show a Coulombic efficiency higher than 97% upon the initial cycles, and a retention strongly dependent on the electrode formulation. Therefore, this study suggests a careful control of the electrode in terms of current collector design and slurry composition to achieve good electrode morphology, mechanical stability, and promising electrochemical performance in practical Li-S cells.
Population Subgroups at Risk of Unhealthy Changes in Food and Beverage Consumption During COVID-19 Lockdowns
Authors: Booth Leon , Santos Joseph Alvin , Hoek Annet C. , Webster Jacqui , Pettigrew Simone
Published: March 2023

Background

Understanding health behaviour changes during the COVID-19 pandemic can assist in developing strategies to promote healthy lifestyles at such times. The aim of this exploratory study was to examine whether the frequency of consuming unhealthy foods and beverages changed during lockdown and whether certain population subgroups were more likely to make such changes.

Method

An online survey was administered to a national sample of 4022 Australian adults (51% female, mean age 48 years). Generalised linear models with generalised estimating equations were used to identify whether demographic characteristics (age, gender, education, presence of children in the household, number of people in the household) and beliefs related to COVID-19 were associated with changes in the frequency of consuming alcohol, sweet snacks, salty snacks, and sugary beverages from pre to during lockdown.

Results

Overall, the frequency of consuming the four assessed unhealthy products did not change during lockdown. However, being male and having children at home were consistently associated with unhealthy changes, whereas believing that alcohol or unhealthy diets would exacerbate COVID-19 severity was linked to a decreased frequency of consuming these products respectively. Age, education, and living with more people were also associated with changes in the frequency of consuming some product categories.

Conclusion

During lockdown, certain population subgroups appeared to be at increased risk of more frequent consumption of unhealthy foods and beverages. Believing certain consumption habits are linked to adverse health impacts of COVID was found to reduce frequency of consumption of related products, presenting a potential focus for future public health actions.
Optimization of saturated hydraulic conductivity estimation using kriging in drainage networks
Authors: Hoseini Yaser
Published: March 2023

Statistical analysis of saturated hydraulic conductivity is the fundamental of engineering plans for water resource projects. In the other words, project solutions and designs depend directly on the accuracy of these statistical analyses and the methods that develop them to studied area. One of the recent methods was used to estimate the variables such as hydraulic conductivity is Kriging method. In this study, GIS software was used for this purpose and kriging method was used to estimate the saturated hydraulic conductivity of the soil. Spherical model with nugget effect of 0.0039 and sill of 0.0262 was the best variogram for determining soil hydraulic conductivity in this method, which expressed the high strength of regional variable structure in the studied area. The results showed that the simple kriging method with a regression coefficient of 0.82 has the highest accuracy in modeling the saturated hydraulic conductivity function. Also, the results showed that the geostatistical kriging method for modeling soil hydraulic conductivity index has a higher accuracy in determining saturated soil hydraulic conductivity than the traditional Thiessen method.
Fluoroscopically guided vascular and cardiac transcatheter procedures: a comparison of occupational and patient dose by anatomical region
Authors: Wilson-Stewart Kelly S. , Fontanarosa Davide , Malacova Eva , Trapp Jamie V.
Published: March 2023

X-ray guided procedures are being performed by an increasing variety of medical specialties. Due to improvements in vascular transcatheter therapies, there is an increasing overlap of imaged anatomy between medical specialties. There is concern that non-radiology fluoroscopic operators may not have sufficient training to be well informed of the potential implications of radiation exposure and mitigation strategies to reduce dose. This was a prospective, observational, single center study to compare occupational and patient dose levels when imaging different anatomical regions during fluoroscopically guided cardiac and endovascular procedures. Occupational radiation dose was measured at the level of the temple of 24 cardiologists and 3 vascular surgeons (n = 1369), 32 scrub nurses (n = 1307) and 35 circulating nurses (n = 885). The patient dose was recorded for procedures (n = 1792) performed in three angiography suites. Abdominal imaging during endovascular aneurysm repair (EVAR) procedures was associated with a comparatively high average patient, operator and scrub nurse dose despite additional table-mounted lead shields. Air kerma was relatively high for procedures performed in the chest, and chest + pelvis. Higher dose area product and staff eye dose were recorded during procedures of the chest + pelvis due to the use of digital subtraction angiography to evaluate access route prior to/during transaortic valve implantation. Scrub nurses were exposed to higher average radiation levels than the operator during some procedures. Staff should be cognizant of the potentially higher radiation burden to patients and exposed personnel during EVAR procedures and cardiac procedures using digital subtraction angiography.
Differentiation of activity rhythms and space use between two competing water shrew species in a laboratory experiment
Authors: Sęk Oliwia , Al Belbeisi Roula , Rychlik Leszek
Published: March 2023

Hypotheses
about the differentiation of activity rhythms and space use between two competing species of water shrews, Neomys anomalus [AA] and N. fodiens [FF], were verified in a laboratory experiment. The animals were kept together for 2 months in an enclosure (195 × 145 cm) and their activity was video recorded using the time-lapse mode. Changes in activity rhythms, distances kept between active animals, and frequency of interspecific conflicts were compared between the early (first 24 h) and late (last 24 h, after 2 months) phases of the animals’ coexistence in the mixed group. In both phases, the activity of both species was relatively evenly distributed over 24 h, with breaks in activity nearly every 1 h. During the early phase, both species were equally and simultaneously active, whereas in the late phase, as predicted, the activity of FF was lower than that of AA, and asynchronous. In the late phase, pairs of different species (F-A) were rarely active simultaneously and kept long inter-individual distances. Consequently, the number of conflicts decreased. The results suggest that, over time, water shrews can develop mechanisms diminishing interference competition, which are based on shifts in activity rhythms, maintaining distance between individuals, and the rare usage of the same shelters and feeding sites.
Responses of maize germination, root morphology and leaf trait to characteristics of lead pollution: a case study
Authors: He Yongjian , Jiang Ranran , Hou Xiuli
Published: March 2023

On base of the content of Pb in the soil under different land use patterns in Lanping Lead-zinc mining area, Yunnan in southwest China, the root morphology and leaf traits of maize in different concentration Pb (20, 40, 60, 80, 100, 150, 200, 500, 1000, 2000, 3000 mg/L) were analyzed. The results showed that maize germination rate, germination vigor and growth index decreased with the increase of Pb concentration. The root length, surface area of maize increased by 0.21%–81.58%, 8.99%–73.43%, 1.50%–77.37%, respectively, under 20–500 mg/L Pb concentration. However, these parameters under 1000–3000 mg/L Pb concentration decreased by 37.86%–553.54%, 44.99%–766.16%, 55.99%–92.81%, respectively, and these lowest value appeared in 3000 mg/L Pb treatment. The root volume of maize increased by 4.57%–89.25% in 20–80 mg/L Pb concentration, and it decreased with the increase of Pb concentration when the Pb concentration was higher than 80 mg/L and decreased by 94.13% in 3000 mg/L Pb. The root surface area and length of 0.50–1.00 diameter class were higher than those of other diameter classes, and these value of maize under 500 mg/L Pb were higher than those of other concentrations. The length and perimeter of maize leaves with the highest value of 220.36 and 962.68 mm, respectively appeared in 60 mg/L Pb treatment. The leaf width and area of maize with the highest value of 15.68 mm and 2448.31 mm2, respectively, appeared in 40 mg/L Pb treatment, which indicated that the leaf traits of maize were promoted by low concentration Pb and inhibited by high concentration Pb.
Computational analysis of crosstalk between transcriptional regulators and RNA-binding proteins suggests mutual regulation of polycomb proteins and SRSF1 influencing adult hippocampal neurogenesis
Authors: Nishanth M. J. , Jha Shanker
Published: March 2023

Background

Adult hippocampal neurogenesis (AHN) is a clinically significant neural phenomenon. Understanding its molecular regulation would be important. In this regard, most studies have focused on transcriptional regulators (TRs), epigenetic modifiers, or non-coding RNAs. RNA-binding proteins (RBPs) have emerged as dominant molecular regulators. It would be significant to understand the potential cross-talk between RBPs and TRs, which could influence AHN.

Methods

The present study employed computational analyses to identify RBPs and TRs regulating AHN, followed by the analysis of their interaction networks and detection of hub proteins. Next, the potential mutual regulation of hub TRs and RBPs was analyzed. Additionally, hippocampal genes differentially expressed upon exercise were analyzed for potential regulation by the identified TRs and RBPs.

Results

105 TRs and 26 RBPs were found to influence AHN, which could also form interactive networks. Polycomb complex proteins were among the TR network hubs, while HNRNP and SRSF family members were among the hub RBPs. Further, the polycomb complex proteins and SRSF1 could have a mutual regulatory relationship, suggesting a cross-talk between epigenetic/transcriptional and post-transcriptional regulatory pathways. A number of exercise-induced hippocampal genes were also found to be potential targets of the identified TRs and RBPs.

Conclusion

SRSF1 may influence post-transcriptional stability, localization, and alternative splicing patterns of polycomb complex transcripts, and the polycomb proteins may in turn epigenetically influence the SRSF1. Further experimental validation of these regulatory loops/networks could provide novel insights into the molecular regulation of AHN, and unravel new targets for disease-treatment.
Prevalence and predictors of depression among women in Afghanistan: a cross-sectional study
Authors: Neyazi Ahmad , Haidarzada Ahmad Shoaib , Rangelova Vanya , Erfan Adiba , Bashiri Bahara , Neyazi Mehrab , Faizi Naweed , Konşuk-Ünlü Hande , Griffiths Mark D.
Published: March 2023

Depression is a very common mental health illness characterized by a cluster of signs and symptoms ranging from mood disturbances and sleep or appetite disorders to physical manifestations of the body. The purpose of the present study was to estimate the prevalence of depression and its related factors among Afghan women. A cross-sectional study was conducted among women between July 14, 2021, to August 15, 2021, in Kabul, Mazar-e-Sharif and Samangan provinces (Afghanistan). A total of 664 Afghan women participated in the study (mean age = 28.85 years; SD ± 11.57). In order to assess depression among participants, the 19-item validated Dari version of the Center for Epidemiological Studies–Depression Scale was used. Approximately four-fifths of the sample had depression symptoms (79.1%). Participants with depression symptoms were significantly more likely to (i) be aged over 30 years, (ii) live in rural areas, (iii) have a low-income level, (iv) not have an occupation, (v) have any disease/illness, and (vi) have experienced an event that had mentally affected them in the past month. Considering the high prevalence of depression symptoms among Afghan women, there is a need to integrate mental health services for women in Afghanistan. The use of interventions including regular screening for depression symptoms, and educating women and girls concerning the symptoms of depression for early self-diagnosis are essential.
A discussion of model asperities as a method to study friction in metal forming
Authors: Zwicker Maximilian , Bay Niels , Nielsen Chris V.
Published: March 2023

The present work discusses the use of model asperities as a method for studying asperity flattening in metal forming. Asperity flattening and the resulting real contact area largely influence friction in metal forming. In order to gain a fundamental understanding of asperity flattening, a method of choice often is to use model asperities. Here, macroscopic model surfaces are emulating real surface topographies. The work presents the method in a historic context, explains the method, lists advantages and disadvantages, and discusses the method in terms of whether the insights gained on model asperities are of qualitative or quantitative nature. In conclusion, the method is a valid tool to fundamentally study asperity flattening. It is, however, not always possible to transfer obtained conclusions quantitatively from model surfaces to real surfaces.
Strategy-Making and Organizational Evolution
Authors: Burgelman Robert Alexander , Snihur Yuliya , Thomas Llewellyn Douglas William
Published: March 2023

This Element presents several frameworks of strategy-making that serve to analyze organizational evolution processes within and beyond the firm. These frameworks form an integrated evolutionary ecological lens to examine the dynamics of strategy-making in organizational evolution. They highlight the role of the internal selection environment for analyzing processes and practices at various managerial levels (top, middle, and operational) within the organization. The Element also explains the role of the CEO in maintaining and updating the internal selection environment and contributing to organizational evolution, as well as making. fundamental decisions about organizational splits of the firm's business models as an ecosystem evolves.
Influence of clearance and structural coupling parameters on shimmy stability of landing gear
Authors: Ruan S. , Zhang M. , Hong Y. , Nie H.
Published: March 2023

There are many factors causing the shimmy of the aircraft landing gear and structural clearance of landing gear is a typical factor. Some aircraft in service or operation did not shimmy before, but suddenly appeared after a period of use. To solve the problem of clearance shimmy during the service of a certain aircraft, we established a dynamic model of rotating gear with clearance based on the flexible multi-body dynamics model of landing gear and L-N contact theory. We defined different types of clearance and established a mechanical model of aircraft pendulum vibration considering the clearance of landing gear structure for dynamic simulation, and studied the effects of different clearance types, clearance size of motion pair and different clearance positions on the stability of pendulum. The results show that the axial clearance has little effect on the shimmy performance of landing gear; the radial clearance has a certain effect on the shimmy performance of medium speed running, which slightly improves the shimmy damping required by medium speed running; the rotational clearance affects the shimmy performance of the nose landing gear by affecting the force transmission of structural components. The required shimmy damping coefficient increases at low speed and decreases at high speed. The main reason for the return clearance is that during the return, the shimmy damper does not work, which leads to the decrease of the shimmy damping performance and the increase of the required shimmy damping coefficient in the whole speed range. Meanwhile, the structural clearance will increase the shimmy frequency of the nose landing gear. By analysing the yaw angle of the nose landing gear and the time domain curve of the yaw angle of the yaw damper, we can determine which structure of the landing gear and which type of clearance is the cause of the yaw. Finally, the coupling effect caused by the main structural parameters of the landing gear in “gap shimmy” was analysed according to different mechanical stability distances and strut stiffness of the nose landing gear, providing reference for aircraft anti-shimmy design, nose landing gear fault diagnosis and nose landing gear maintenance support.
Estimating local surface glacier mass balance from migration of the 1918 Katla eruption tephra layer on Sléttjökull, southern Iceland
Authors: Hagg Wilfried , Mayer Christoph , Münzer Ulrich , Barbosa Natalie , Schuler Hans-Martin , Staudacher Matthias
Published: March 2023

We use the apparent horizontal shift of an englacial tephra layer outcrop to calculate local glacier mass balance on Sléttjökull, a lobe of Mýrdalsjökull in Southern Iceland. For this approach, the dipping angle of the englacial tephra layer in the glacier upstream of the outcrop and the flow velocity of the ice need to be known. An earlier investigation was expanded by the application of ground-penetrating radar, detecting the depth of the tephra along tracks with a total length of 10 km. Interpolation between the tracks enables us to derive the dipping angle of the layer along several flow lines. Together with glacier surface velocities, determined from feature tracking, we are able to estimate the local surface mass balance from the horizontal displacement of the tephra outcrop using freely available satellite imagery without additional fieldwork. The earlier local balance series was extended to the period 2014/15 to 2019/20. Although the results for the individual profiles differ slightly from each other, they show the same temporal pattern and clear variations from year to year. The results are compared to traditional mass-balance data from Hofsjökull. The two series show a good agreement in their interannual variability.
Behavioral public choice and policing in America
Authors: Palagashvili Liya , Goodman Nathan P.
Published: March 2023

A substantial experimental literature in behavioral economics and psychology finds that individuals rely on heuristics and cognitive biases when they make decisions. These heuristics and biases impact the choices of individuals from all walks of life, including police officers entrusted with the power to enforce laws. Individuals act within an institutional context. We examine how the institutions that structure American policing interact with the heuristics and biases of individual police officers. We then suggest institutional changes that may result in better performance from boundedly rational police officers.
Prosecuting and Propagating Emotional Harm: The Criminalisation of HIV Nondisclosure in Canada
Authors: Bogosavljević Katarina , Kilty Jennifer M.
Published: March 2023

This article explores emotional harm in the context of the criminalization of HIV nondisclosure in Canada. With the exception of Matthew Weait in the United Kingdom, few scholars have examined what harm means in cases of HIV nondisclosure. We conceptualize the harm that follows nondisclosure as an affective response to the “HIV positive Other” and argue that law creates a legal norm about what harm is and feels like in cases of HIV nondisclosure when there is no clear consensus about how harm should be defined. Mobilizing the sociology of emotions literature, we contend that criminalizing HIV nondisclosure engages affective, moral, and criminal censure to regulate the behaviours of people living with HIV/AIDS (PLWH), thus reproducing HIV stigma and propagating emotional harm for PLWH. Canada’s response to HIV nondisclosure should instead involve a transformative justice approach that avoids the harm of criminalization and imprisonment while recognizing the emotional harm experienced by complainants.
Parents’ mental health literacy, preferred school counsellor roles, and intention to follow up referrals
Authors: Bignold Monica L. G. M. , Anderson Donnah
Published: March 2023

Many mental illnesses have onset during adolescence, and if untreated may have long-term negative outcomes. Parents and school counsellors can assist adolescents by monitoring for mental illness and facilitating appropriate support. The present study investigated parents’ mental health literacy (MHL), preferred views of school counsellor roles, and intention to follow up referrals. Eighty-seven Australian parents of current secondary school students were recruited to an online cross-sectional survey via convenience sampling. Results showed that, on average, parents had good MHL, moderately endorsed school counsellor roles, and were committed to following up referrals. Higher MHL, but not preferred school counsellor roles, predicted intention to follow up referrals to general practitioners and specialised mental health services. Findings support targeted psychoeducational intervention for parents regarding MHL and the role of the school counsellor and directions for future research are discussed.
The 1972 Meadows report: A wake-up call for plant science
Authors: Hamant Olivier
Published: March 2023

The 1972 Meadows report, ‘the limits to growth’, predicted a global socio-economic tipping point during the twenty-first century. Now supported by 50 years of empirical evidence, this work is a tribute to systems thinking and an invitation to take the current environmental crisis for what it is: neither a transition nor a bifurcation, but an inversion. For instance, we used matter (e.g., fossil fuel) to save time; we will use time to preserve matter (e.g., bioeconomy). We were exploiting ecosystems to fuel production; production will feed ecosystems. We centralised to optimise; we will decentralise to support resilience. In plant science, this new context calls for new research on plant complexity (e.g., multiscale robustness and benefits of variability), also extending to new scientific approaches (e.g., participatory research, art and science). Taking this turn reverses many paradigms and becomes a new responsibility for plant scientists as the world becomes increasingly turbulent.
Mid-Pleistocene drainage rearrangement of the Dadu River in response to plate convergence in southeastern Tibet
Authors: Zheng Yong , Li Haibing , Pan Jiawei , Gong Zheng , Wang Ping , Lai Ya , Zhao Zhongbao , Liu Fucai
Published: March 2023

The rearrangement of drainage basins provides critical insight into crustal deformation and geodynamic mechanisms. Near the southeastern boundary of the Tibetan Plateau, the Dadu River abruptly shifts from south- to east-flowing, providing important implications for regional tectonogeomorphic development since the mid-Pleistocene. South of the bend, the headwaters of the Anning River occupy an unusually wide valley. Field investigations show that large quantities of fluvial/lacustrine sediments are widespread along the Dadu and Anning rivers and are exposed at their drainage divide. Detrital zircon U-Pb age patterns confirm that these fluvial/lacustrine sediments are the remnants of the paleo-Dadu River, which strongly suggests that the paleo-Dadu River originally flowed southward into the Anning River. The cosmogenic nuclide burial ages of the lacustrine sediments along the Dadu and Anning rivers suggest deposition of these sediments from separate dammed lakes ca. 1.2 Ma ago, ca. 0.6 Ma ago, and ca. 0.9 Ma ago from north to south, respectively. Provenance and burial-age studies indicate that reorganization of the Dadu drainage occurred within the last 0.6 Ma. We propose that this drainage reorganization in southeastern Tibet resulted from progressive convergence between the India and Eurasian plates during the Pleistocene.
IMPACT: A computer program to aid missile system design
Authors: Markham K. C.
Published: March 2023

The design of guided missile systems presents a wide spectrum of problems to engineers in numerous disciplines which range through aerodynamics, electronics and signal processing. Of all the tasks involved in the design process, perhaps the most difficult is the integration of the various technologies into a complete, harmonised system. IMPACT is a computer program which was developed to address the system design aspects of homing guidance missile systems. The aim of this paper is to describe the engineering philosophy and theoretical background to the IMPACT program.
Drag-reduction test of riblets using ARE’s high speed buoyancy propelled vehicle — MOBY-D
Authors: Choi Kwing-So
Published: March 2023

Drag-reduction performance of riblets on an axi-symmetric body was investigated using ARE’s High Speed Buoyancy Propelled Vehicle (MOBY-D) at high Reynolds number. Approximately 35% of the wetted body surface was applied with riblets in situ using BMT’s RIBCOATTM process, and net drag reductions between 0 and 3.0% were observed during the flight. The drag reduction increased toward the ascent as the vehicle acceleration decreased, indicating that the favourable effects that riblets have on the boundary layer structure may be susceptible to acceleration.
The effects of aerofoil profile on wing buffet at low speeds
Authors: Lucas C. A. , Maull D. J.
Published: March 2023

The unsteady loads on two wings, one exhibiting a trailing edge separation, the other a leading edge separation have been measured. It has been found that there are differences between the two wing loads, one having a large scale viscous-inviscid interaction producing high loads at a low frequency.
Mixed structured-unstructured meshes for aerodynamic flow simulation
Authors: Weatherill N. P.
Published: March 2023

Mesh generation is proving to be an important aspect of computational aerodynamics. Over the last few years the topic has received much attention. Methods based on the structured and unstructured philosophies both have their advantages and disadvantages. This paper discusses the possible benefits to be achieved in composite structured-unstructured meshes. An algorithm is described which can solve the Euler equations for inviscid flow on such meshes. Three applications of the composite approach are then described. The first example shows the use of regions of assembled triangles to improve the quality of flow results on a poor quality structured mesh. The second illustrates how geometrically complicated aerodynamic configurations can be treated by utilising local regions of unstructured mesh within a globally structured mesh. Finally, a method of mesh/flow adaptivity is described whereby a structured mesh is enriched in appropriate regions of the domain by the addition of meshes consisting of an assembly of triangles. The results show that distinct benefits can be obtained from this composite approach.
Performance — robustness trade off of eigenstructure assignment applied to rotorcraft
Authors: Innocenti M. , Stanziola C.
Published: March 2023

Eigenstructure assignment has been widely used in the past for the synthesis of flight control systems in the time domain. The method, although offering a straightforward way of determining static compensators which satisfy the specifications in terms of desirable time response characteristics, lacks the property of guaranteeing stability margins like the linear quadratic regulator (LQR) methodology. The present paper analyses the performance-robustness properties of eigenstructure assignment against the standard LQR in order to define a loop transfer recovery procedure similar to that of the LQG/LTR. Two applications are described in which helicopter flight controllers are synthesised by eigenstructure assignment and possess robustness properties comparable to those of similar quadratic regulators and yet resulting in a simpler compensator structure. The applications are chosen to correspond to two flight conditions reflecting the aim of generality of the comparison.
Solution of the Euler equations on unstructured grids for two-dimensional compressible flow
Authors: Stolcis L. , Johnston L. J.
Published: March 2023

A method for the numerical solution of the two-dimensional Euler equations on unstructured grids has been developed. The cell-centred symmetric finite-volume spatial discretisation is applied in a general formulation that allows the use of arbitrary polygonal computational cells. The integration in time, to a steady-state solution, is performed using an explicit, multi-stage procedure, with standard convergence acceleration techniques such as local time stepping, enthalpy damping and implicit residual smoothing. Accuracy of solution, in terms of minimising spurious entropy production, is achieved through careful treatment of the artificial dissipative terms near boundaries. Standard test cases for both subcritical and supercritical flows, including single- and multi-element aerofoils have been used to validate the method.
Alleviation of shock oscillations in transonic flow by passive controls
Authors: Raghunathan S. , Hall D. E. , Mabey D. G.
Published: March 2023

Passive control experiments were made on an 18% thick biconvex aerofoil model in Mach number range giving shock oscillations and at a Reynolds number of 0.7 x 106 with fixed boundary layer transition. The control methods studied included a passive control of shock wave boundary layer interaction by a porous surface and a cavity, and a buffet breather made of holes connecting upper and lower surfaces of the aerofoil. The experiments show that the shock oscillations can be virtually eliminated by these methods. A physical explanation is given for the success of these passive controls.
Response of hang gliders to control
Authors: de Matteis Guido
Published: March 2023

A general dynamic model of the hang glider is applied to the analysis of response to control. The transfer functions of the glider to the longitudinal and lateral controls are formulated and some significant results, in terms of frequency response are presented and discussed. The relevant effects of the unsteady aerodynamics on the dynamics of the system are shown and the characteristics of poor lateral control are confirmed as observed in flight.
Recent developments in CFD at ARA
Authors: Bocci A. J.
Published: March 2023

The paper discusses recent work in the Theoretical Division at the Aircraft Research Association Limited (ARA) on the modelling of complex configurations, rotors, propulsion and viscous flows. The general features of the ARA multiblock system, which provides a grid generation and Euler flow solution capability for complex configurations, are discussed. Although very successful, the system has various limitations, in particular the tendency for the grid quality to depend on configuration complexity and type. A new multiblock system is being developed which allows regions of unstructured grid to be included, giving increased flexibility in dealing with complex geometries and other improvements. Work on rotors has included the development of a new Euler code for propellers, as a replacement for the code in current use. Improvements in flow solution offered by the new code are illustrated. In the propulsion field, the extension of a viscous-coupled Euler code for afterbody flows to a complete cowl unit is described briefly. The code is particularly relevant to the new generation of large civil turbofans. Work on Navier-Stokes methods for afterbody/nozzle flows is also discussed. Other work on viscous flows includes a 2-D investigation into viscous modelling with hybrid grids, and the further development of an established transonic flow aerofoil code.
Analysis of general shells by flat facet finite
element approximation
Authors: Allman D. J.
Published: March 2023

A standard flat facet approximation for finite element analysis of general thin shells has been sought after for many years, but fundamental difficulties hindered the development of a definitive solution. Recent advances in the finite element method, however, have provided more rational resolutions of some of these difficulties than the kind of artifices which were employed formerly. This paper completes the theory of a basic triangular flat shell element which incorporates modern developments and meets practical criteria of mathematical simplicity and general applicability. The flat facet shell element is also, potentially, an appropriate basis for constructing a better curved approximation to a shell surface in order to achieve improved accuracy. Numerical results are given for a variety of shell test problems to provide comparisons with accepted benchmark solutions and to assess the available accuracy relative to other finite element formulations.
The effects of icing on the dynamic response of thick aerofoils
Authors: Lucas C. A.
Published: March 2023

Vibration of a flexible wing strut of 30% thickness/chord ratio occurred during icing trials of a commuter aircraft. This was caused by the formation of ice on the leading-edge of the strut producing a ‘double-horned’ ice shape. The two horns formed one above the other, having very sharp leading-edges with radii less than 0·6% of the strut chord of 0·23 m.

Wind tunnel testing demonstrated that, over a limited range of incidence angle, the flow around the flexible strut was dominated by a long separation bubble that periodically ‘burst’ and re-attached. This occurred at a reduced frequency of nominally 0·06, based upon the chord of the profile and the free stream velocity. The periodic flow was also spatially highly coherent, producing relatively large unsteady forces compared with the buffet forces generated by incoherent turbulent separated flows.

A high-speed film was made using smoke visualisation of the flow around a 40% rigid scale model of the strut. This was used to correlate the unsteady pressure field, measured at 18 points around the profile, with the dynamic behaviour of the separation bubble.

The periodicity was found to be inherent in the flows over both the flexible and rigid struts for a limited range of incidence, occurring even when structural response was restrained to a level below that at which lock-in occurred between the flow and the response motion. The peak value of the unsteady pressure was measured on the top surface of the upper ice horn. The root mean square value of 18% of the free stream dynamic pressure was measured, with response restrained to below the lock-in threshold.