bluuebunny/crossref_metadata_2025 huggingface dataset:
Reduced Steroid Synthesis in the Follicular Fluid of MTHFR 677TT Mutation Carriers: Effects of Increased Folic Acid Administration
Authors: Pavlik Roman , Hecht Stephanie , Noss Ulrich , Soldin Offie P. , Mendu Rao D. , Soldin Steven J. , Lohse Peter , Thaler Christian J.
Published: September 2022

Objective To compare steroid profiles in the follicular fluid (FF) from women homozygous for the methylenetetrahydrofolate reductase (MTHFR) 677C>T mutation and wildtype controls
and to correlate it with the folic acid administration scheme applied at the time of oocyte retrieval.

Design Retrospective single center study.

Subjects and Methods Infertile patients treated by using assisted reproductive techniques were genotyped routinely for the MTHFR 677C>T mutation. In 2006 they had received folic
acid supplementation doses of 400 µg daily per os. This group was designated Group-400 (n = 10). From 2008 onwards, all of our infertility patients received a daily dose of 800 µg folic acid
per os. Women from this group were designated Group-800 (n = 28). FF were collected and a panel of steroid hormones (estradiol, estrone, estriol, cortisol, progesterone, 17-OH progesterone,
testosterone, androstenedione, aldosterone, DHEA, and DHEA-S) was measured by isotope dilution liquid chromatography-tandem mass spectrometry employing atmospheric pressure photo ionization
(APPI).

Results In Group-400, the FF hormone profile confirmed a significant reduction of estradiol in homozygous 677TT carriers (0.52 ± 0.08-fold, exact p = 0.032) and for the first time
also revealed significantly reduced estriol concentrations in these individuals (0.54 ± 0.05-fold, p = 0.016), as compared to wildtype controls. In Group-800, no significant differences were
found for concentrations of any of the steroid hormones between homozygous 677TT carriers and wildtype controls.

Conclusions The current findings support and extend previous reports on reduced concentrations of specific steroid hormones in follicular fluids of homozygous MTHFR 677C>T
mutation carriers. The restoration of the FF hormone profile by elevated-dose folic acid supplementation might impact performing ART in infertile women with the MTHFR 677TT-genotype. Further
adequately powered studies are necessary to verify our finding and to demonstrate the clinical effect of enhanced folic supplementation on ovarian function.
One-Step Simultaneous Synthesis of an Industrially Important Rubber Accelerator and a Lubricant Additive by Disulfide Bond Contraction
Authors: Xu Hao-Xing , Fu Shun-Guo , Tao Yu-Hong , Wang Xiao , Luo Peng-Hao , Song Zhi-Qiang , Zhang Yan , Zhang Zhi-Liang
Published: September 2022

A sustainable and atom-economic synthesis of the widely used rubber accelerator tetramethylthiuram monosulfide (TMTM) from tetramethylthiuram disulfide is reported. Triphenyl phosphite (TPPi) is employed as a green reductant to replace the usual sodium cyanide, which poses a severe safety risk due to its high toxicity. The new process proceeds smoothly under mild conditions with an excellent yield of TMTM. This single-step one-pot method also has the potential for producing the industrially important lubricant additive O,O,O-triphenyl thiophosphate as a high-added-value byproduct.
Potentised Black Lead in the Treatment of Polycystic Ovarian Syndrome: An Evidence-Based Case Report
Authors: Rajachandrasekar Bhuvaneswari , Sunny Anita
Published: September 2022

Polycystic ovarian syndrome (PCOS) is a common condition among females of the childbearing age group. The exact cause of PCOS is unknown and increased levels of male hormones are believed to cause anovulation. It can cause several long-term complications, including infertility, metabolic disorders and cardiovascular disorders. PCOS is diagnosed based on Rotterdam diagnostic criteria. Globally, the estimated prevalence of PCOS ranges between 5 and 15%. The prevalence in south India is 6%. In this case report, a case of PCOS successfully treated with individualised medicine Graphites is given. The improvement is evident from symptomatic relief and decreased ovarian volume on ultrasonography abdomen and pelvis after 9 months of homeopathic treatment. Subsequently, the patient conceived. Thus, homeopathic medicine was found effective in the treatment of this PCOS case.
Hailey-Hailey Disease Treated with Individualised Homoeopathy—An Evidence-Based Case Report
Authors: Dastagiri P. , Pratap Nirmala
Published: September 2022

Hailey-Hailey disease (HHD) is a rare autosomal dominant skin disorder presented as blistering dermatosis with recurrent erythematous plaques, leading to erosions, fissures and vegetations seen in the skin folds. Prevalence of this disease occurs in 1 to 4 per 100,000 affected between third and fourth decade, mostly either under-reported or misdiagnosed. Under standard conventional treatment, recurrence and remissions are typical. Therefore, it affects the quality of life compared with other skin disorders. However, with the individualised homoeopathic medicine, Psorinum, this rare case was treated without topicals; no recurrence of the complaints and adverse effects were observed in 1 year of follow-up. Furthermore, changes in the dermatology life quality of life questionnaire score from 20 (at baseline) to zero have been noticed; the modified Naranjo criteria for homeopathy total score was +9 out of +13, providing evidence attributed by the intervention. This case report reinforces that individualised homoeopathic intervention is beneficial in rare skin disorders like HHD, and pooling such data will develop future research concepts in this area.
Risk Assessment of Red Cell Transfusion in Congenital Heart Disease
Authors: Zürn Christoph , Höhn René , Hübner David , Umhau Markus , Kroll Johannes , Kari Fabian A. , Humburger Frank , Maier Sven , Stiller Brigitte
Published: September 2022

Background The storage time of packed red blood cells (pRBC) is an indicator of change in the product's pH, potassium, and lactate levels. Blood–gas analysis is a readily available bedside tool on every intensive care ward to measure these factors prior to application, thus facilitating a calculated decision on a transfusion's quantity and duration.

Our first goal is to assess the impact of storage time on pH, potassium, and lactate levels in pRBC. The influence of those parameters in the transfused children will then be evaluated.

Methods In this retrospective study, we conducted blood–gas analyses of pRBC units before they were administered over 4 hours to neonates, infants, and children in our pediatric cardiac intensive care ward. All patients underwent regular blood–gas analyses themselves, before and after transfusion.

Results We observed a highly significant correlation between the storage time of pRBC units and a drop in pH, as well as an increase in potassium and lactate of stored red cells (p< 0.0001). Median age of recipients with a complete blood–gas dataset was 0.1 (interquartile range [IQR] = 0.0–0.7) years; median pRBC storage duration was 6 (IQR = 5–8) days. Further analyses showed no statistically significant effect on children's blood gases within 4 hours after transfusion, even after stratifying for pRBC storage time ≤7 days and >7 days.

Conclusion Stored red blood cells show a rapid decrease in pH and increase in potassium and lactate. Slow transfusion of these units had no adverse effects on the recipients' pH, potassium, and lactate levels.
Italians locked down: people’s responses to early COVID-19 pandemic public health measures
Authors: Romano Virginia , Ancillotti Mirko , Mascalzoni Deborah , Biasiotto Roberta
Published: September 2022

At the beginning of 2020, the widespread diffusion of SARS-CoV-2 rapidly became a worldwide priority. In Italy, the government implemented a lockdown for more than two months (March 9–May 18). Aware of the uniqueness of such an experience, we designed an online qualitative study focused on three main dimensions: daily life during the lockdown, relationships with others, and public health issues. The aim was to gain insights into people’s experiences of, and attitudes toward, the changes caused by public health measures implemented as a response to the COVID-19 pandemic. We conducted 18 semi-structured interviews with Italian residents. The interviewees were recruited through mediators using purposive sampling to obtain a balanced sample with respect to age, gender, education, and geographical residence. Interviews were analyzed through qualitative content analysis. The lockdown affected a variety of aspects of people’s life, resulting in a significant re-shaping of daily activities and relationships. These changes, which entailed both positive and negative aspects, were met with resilience. Even though public health measures were generally considered acceptable and adequate, they were also perceived to generate uncertainty and stress as well as to reveal tensions within the public health system. When tasked with imagining a scenario with saturated intensive care units and the need for selection criteria, respondents showed a tendency to dodge the question and struggled to formulate criteria. Media and news were found to be confusing, leading to a renewed critical attitude toward information. The findings shed some light on the impact of the lockdown on people’s daily life and its effects on relationships with others. Furthermore, the study contributes to an understanding of people’s reasons for, and capacity to respond to, emergency public health measures.
Psychosocial indicators of individual behavior during COVID 19: Delphi approach
Authors: Abbas Wijdan , Eltayeb Shahla
Published: September 2022

The COVID-19 pandemic revealed the weakness of the health care system to incorporate indicators of human behavior in the rapid response to the virus. This study aims to establish consensus on the psychosocial indicators of COVID-19 preventive behaviors during the initial phase of the outbreak in Arab countries. This qualitative study used a combined scoping review of the literature to develop the 24 psychosocial indicators and the Delphi approach with a panel of 27 experts from nine Arab countries to achieve a consensus on preventive behavior indicators. The most robust agreement with an average rating of at least 4 was found for five social indicators including Belief System with an average rating (5). Income Status average rating (4.9). Family Commitment average rating (4). Faith average rating (4). Kinship System average rating (3.9). Four psychological indicators were identified namely Self-Efficacy with an average rating of (5). Perception of Hazard with an average rating of (4.5). Motivation with an average rating of (4.5). Stigma with an average rating of (4.2). The nine indicators provide a strong base for redesigning pandemic control interventions. The Delphi study demonstrates the feasibility of a participatory approach during the outbreak of COVID-19. Moreover, future interventions need to accommodate individual psychological and social determinants to increase adherence and decrease resistance to public health guidelines.
Single motherhood in Ghana: analysis of trends and predictors using demographic and health survey data
Authors: Ayebeng Castro , Dickson Kwamena Sekyi , Seidu Abdul-Aziz , Amo-Adjei Joshua
Published: September 2022

The rising rate of single-mother families has gained scholarly and policy attention. Understanding the dynamics in the socio-economic and demographic transformations that have led to the relatively high single-mother families in Ghana is important to advance policy and intervention to mitigate adverse effects of single motherhood. The study sought to examine the trends and predictors of single motherhood in Ghana from 1993 to 2014. This paper was based on data from the last five waves of the Ghana Demographic and Health Survey. Descriptive statistics of proportions with Chi-square test and binary logistic regression were used to assess individual and contextual factors associated with single motherhood in Ghana. The proportion of single motherhood increased significantly over the period from 14.1% in 1993 to 19.5% in 2014. Premarital birth emerged as the major pathway to single motherhood. Among individual factors, the likelihood of single motherhood declines as age at first sex [OR = 0.58; 95% CI = 0.48,0.70] and first birth [OR = 0.43; CI = 0.32,0.59] were 25 years and above. Also, Contraceptive users were less likely to be single mothers than non-users. Contextually, women who profess Islam [OR = 0.58; 95% CI = 0.46, 0.74] were less likely to be single mothers than women who had no religious affiliation. We observed that, after accounting some important factors, women with higher economic status—richer [OR = 0.76; 95% CI = 0.59,0.96] and richest [OR = 0.57; 95% CI = 0.31,0.56] were less likely to be single mothers than poorest women. The findings give an impression of single mothers being over-represented among economically poor women. Policies and programmes meant to mitigate adverse effects of single motherhood should also focus on empowering single mothers and their children as a way of alleviating poverty and improve the well-being of children in this family type, as well as enhance Ghana’s capacity to attain the Sustainable Development Goal 1, particularly target 1.2.
Intrinsically enhanced anomalous Hall conductivity and Hall angle in Sb-doped magnetic Weyl semimetal Co3Sn2S2
Authors: Shen Jianlei , Zhang Shen , Liang Tingting , Wang Jing , Zeng Qingqi , Wang Yibo , Wei Hongxiang , Liu Enke , Xu Xiaohong
Published: September 2022

The emerging magnetic topological materials bring a new opportunity to obtain giant transverse transport effects. In this work, a greatly enhanced anomalous Hall effect (AHE) is obtained in electron-doped magnetic Weyl semimetal Co3Sn2−xSbxS2, showing a maximum anomalous Hall conductivity (AHC) of ∼1600 Ω−1 cm−1 and an anomalous Hall angle of ∼26%. Based on the qualitative and quantitative analysis of scaling models, the enhanced AHC comes from the intrinsic mechanism related to the Berry curvature of the topological band structures. A small amount of electron doping still makes the EF around the gapped nodal rings. At the same time, disorder doping leads to the splitting and broadening of bands, which enhance the Berry curvature and intrinsic AHC. Our work provides an important guidance for the design and development of large AHE in magnetic topological materials.
Percolation transitions in interdependent networks with reinforced dependency links
Authors: Li Jie , Wang Ying , Zhong Jilong , Sun Yun , Guo Zhijun , Fu Chaoqi , Yang Chunlin
Published: September 2022

Dependence can highly increase the vulnerability of interdependent networks under cascading failure. Recent studies have shown that a constant density of reinforced nodes can prevent catastrophic network collapses. However, the effect of reinforcing dependency links in interdependent networks has rarely been addressed. Here, we develop a percolation model for studying interdependent networks by introducing a fraction of reinforced dependency links. We find that there is a minimum fraction of dependency links that need to be reinforced to prevent the network from abrupt transition, and it can serve as the boundary value to distinguish between the first- and second-order phase transitions of the network. We give both analytical and numerical solutions to the minimum fraction of reinforced dependency links for random and scale-free networks. Interestingly, it is found that the upper bound of this fraction is a constant 0.088 01 for two interdependent random networks regardless of the average degree. In particular, we find that the proposed method has higher reinforcement efficiency compared to the node-reinforced method, and its superiority in scale-free networks becomes more obvious as the coupling strength increases. Moreover, the heterogeneity of the network structure profoundly affects the reinforcement efficiency. These findings may provide several useful suggestions for designing more resilient interdependent networks.
Effect of Mach number on the aeroacoustic feedback loop generating airfoil tonal noise
Authors: Pröbsting S. , Yang Y. , Zhang H. , Li P. , Liu Y. , Li Y.
Published: September 2022

Airfoil tonal noise emission at low-to-moderate Reynolds number and flow conditions featuring a laminar separation bubble close to the trailing edge is often related to an aeroacoustic feedback mechanism and, therefore, the Mach number is a primary parameter for the flow field and noise generation. This study experimentally explores the effect of the Mach number on airfoil tonal noise generation in the nominally incompressible flow regime. Using airfoil profiles of different chord lengths, the Mach number is varied for a constant Reynolds number. Acoustic and flow field measurements for a range of combinations of Reynolds and Mach numbers were conducted. At zero incidence, the tonal noise regime in the Reynolds number domain is found to be sensitive to the Mach number. At non-zero angle of attack (2°), the noise generation is found to be dominated by vortex shedding over a separation bubble on the pressure side. The details of the separation bubble and shedding process depend on the Mach number. The frequencies of the dominant tones and the frequency intervals between tones increase with the Mach number. Moreover, the measured frequency interval can be collapsed using a relation based on the aeroacoustic feedback loop model. The relation is rewritten to separate the effects of the Reynolds and Mach numbers. As a result, the dependence on the Mach number is identified and tested. In contrast, the tonal noise level shows a more complex dependence on details of the laminar separation bubble and the vortex shedding process.
Comparing different charge-state models with experimental data of ion beams penetrating fully and partially ionized plasmas
Authors: Morales Roberto
Published: September 2022

In the present work, we have conducted a study to investigate the validity of three different charge-state models of ion beams penetrating plasma targets through a comparison with a total of five experiments from the literature. We have applied two alternative theoretical approaches. On the one hand, we have used a further extension of our cross-sectional model (CSM) code based on projectile electron loss and capture cross sections (rate equations) that was developed previously [Morales et al., Phys. Plasmas 24, 042703 (2017); R. Morales, Ph.D. thesis (Universidad de Castilla-La Mancha, 2019)]. On the other hand, we also used two charge-state models based on a semi-empirical formalism adapted to the plasma case: the Kreussler model [Kreussler et al., Phys. Rev. B 23, 82 (1981)] and the Gus'kov model [Guskov et al., Plasma Phys. Rep. 35, 709 (2009)]. Specifically, we present the predictions and the interpretation of the charge state of light to heavier ions at high, intermediate, and low velocities in Z-pinch and laser-produced partially and fully ionized plasmas. We are showing that experimental data support our new CSM code based on the cross-sectional formalism. In contrast, the framework based on semi-empirical formulas is less accurate for a precise charge-state prediction, but it can be applied for a reasonable stopping power calculation. Overall, results denote that the Gus'kov model is better suited to stopping power calculations at low projectile velocities and the Kreussler model fits better the energy loss data at intermediate velocities. Additionally, we propose a simple non-equilibrium charge model, derived from the semi-empirical framework, as a function of the ion path and equilibrium charge state.
Research on the pressure field and loading characteristics of air film of air cushion belt conveyor
Authors: Zhang Biao , Meng Wenjun , Zhang Hanzhong
Published: September 2022

The power loss generated by the air cushion belt conveyor when transporting materials mainly depends on the diameter of the orifice, the form of arrangement, and the thickness of the air film. A mathematical model of an air cushion belt conveyor is established through mechanical analysis, and the relationship between load distribution, air film thickness, air film carrying capacity, and power consumption is found. Numerical simulations of orifices of different diameters on the disk groove and the formed air film are carried out, and the loading capacity of the air film was analyzed by observing the stress and deformation of the wire rope core. The results show that the air film formed by the selected type of orifice arrangement in this paper carries the load, which causes the least amount of deformation and stress change in the wire rope core, and the stability of the air film loading capacity is also verified by experiments.
Deformation and seepage properties of raw coal during the simultaneous loading and unloading of axial stress and confining pressure
Authors: Yang Yushun , Zhang Dongming , Dong Yun , Zhang Jihua , Li Xiaoming , Zhang Chunlei , Wu Jingke
Published: September 2022

The mining of coal resources causes the stress on the front and both sides of the working face to be in a complex loading and unloading process, and the gas contained in the coal body migrates, which can cause gasdynamic disasters in severe cases. Therefore, this study designed a three-dimensional stress path based on the in situ stress distribution characteristics of the No. 2461 working face and conducted the experiment on the deformation and seepage characteristics of raw coal under simultaneous unloading (loading) axial stress and loading (unloading) confining pressure. It is considered that in the process of loading axial stress, the volumetric strain increases gradually with the increase in effective stress, and the permeability decreases exponentially with the increase in effective stress. In the process of simultaneous unloading axial stress and loading confining pressure, the volumetric strain of coal sample increases with the increase in effective stress, and the permeability decreases exponentially with the increase in effective stress. However, the processes of simultaneous loading axial stress and unloading confining pressure are opposite, and the variation curves of the two do not overlap, indicating that the coal sample undergoes elastic-plastic deformation after cyclic loading, the permeability cannot be restored to the initial state, and the volumetric strain further expands. The permeability damage rate and maximum permeability damage rate are used to evaluate the recovery degree and reduction range of coal samples' permeability. The volume expansion rate and maximum volume expansion rate are used to evaluate the expansion degree and increase range of coal samples' volume.
An American’s five-country research tour
Authors: Jaffe Tess
Published: September 2022

For one astrophysicist, volunteering for an impromptu transfer to a position in Switzerland turned into a 17-year stint on the European continent.
The link between out-of-pocket costs and inequality in specialist care in Australia
Authors: Pulok Mohammad Habibullah , van Gool Kees , Hall Jane
Published: September 2022

Objective Out-of-pocket (OOP) costs could act as a potential barrier to accessing specialist services, particularly among low-income patients. The aim of this study is to examine the link between OOP costs and socioeconomic inequality in specialist services in Australia. Methods This study is based on population-level data from the Medicare Benefits Schedule of Australia in 2014–15. Three outcomes of specialist care were used: all visits, visits without OOP costs (bulk-billed services), and visits with OOP costs. Logistic and zero-inflated negative binomial regression models were used to examine the association between outcome variables and area-level socioeconomic status after controlling for age, sex, state of residence, and geographic remoteness. The concentration index was used to quantify the extent of inequality. Results Our results indicate that the distribution of specialist visits favoured the people living in wealthier areas of Australia. There was a pro-rich inequality in specialist visits associated with OOP costs. However, the distribution of the visits incurring zero OOP cost was slightly favourable to the people living in lower socioeconomic areas. The pro-poor distribution of visits with zero OOP cost was insufficient to offset the pro-rich distribution among the visits with OOP costs. Conclusions OOP costs for specialist care might partly undermine the equity principle of Medicare in Australia. This presents a challenge to the government on how best to influence the rate and distribution of specialists’ services.
Arsenosugars and arsenolipids are formed simultaneously by the unicellular alga
Authors: Glabonjat Ronald A. , Duncan Elliott G. , Krikowa Frank , Francesconi Kevin A. , Maher William A.
Published: September 2022

Environmental context Arsenic is a globally distributed element, occurring in various chemical forms with toxicities ranging from harmless to highly toxic. We conducted 48-h cell culture experiments under batch and continuous conditions using the ubiquitous marine unicellular alga Dunaliella tertiolecta and evaluated the alga’s arsenic metabolome over time. We found that the alga first methylates the inorganic As taken up from the surrounding water, and then further metabolises the intermediate simultaneously into more complex organo-arsenic molecules like sugars and lipids. These time series experiments are valuable pieces in the puzzle of how algae bio-metabolise arsenic, and in our understanding of the global arsenic cycle. Rationale The uptake of arsenate by algae from oceanic waters and its transformation to arsenosugars and arsenolipids is well established, but the biosynthetic pathways remain largely unknown. Methodology We investigated these pathways by using time-series experiments over 48 h to follow the formation of organoarsenic species from arsenate-enriched medium (15 µg As L−1) by the unicellular alga Dunaliella tertiolecta cultured under batch and continuous culture conditions. We used complementary mass spectrometry methods for the determination and quantification of 14 arsenic species; an additional three species could be quantified but remained unidentified. Results The alga rapidly methylated the arsenate to dimethylarsinate (DMA), which then served as the precursor to arsenosugars and arsenolipids; the concentrations of these complex organoarsenicals increased throughout the experiments accompanied by a concomitant reduction in DMA concentrations. The pattern of compounds formed by the alga was similar for both batch and continuous cultures, but the concentrations were 2–3-fold higher in the continuous culture samples and the increases with time were much clearer. Discussion The data suggest that the arsenosugars and the arsenolipids were mostly formed simultaneously from DMA, although there was an indication that the arsenic phospholipids were at least partly also being formed from the arsenosugars. Overall, the data are consistent with a direct biosynthesis of DMA from arsenate by D. tertioleta, and thereafter a non-specific incorporation of DMA into commonly available alga metabolites encompassing various sugars and lipids.
Analogy in action
Authors: Glaz Adam
Published: September 2022

Analogy as structural similarity is assumed to play a fundamental role in human cognition. This study is
concerned with analogies between spatiotemporal orientation, linguistically-coded perspectival frames, and cultural
experience. Two major types of orientational frames, and thus of cultural perspectival frames, are postulated:
egocentric and allocentric. Those, however, may also be combined into complex hybrid configurations. A case study of a
sample of press discourse is offered, where the egocentric, allocentric, and hybrid perspectival frames are shown to
be interwoven. Ultimately, it is hypothesised that the frames can be extrapolated onto the level of conventionalised,
communal perspectives, i.e. cultural models. Analogy is thus shown to be a powerful, robust cognitive mechanism
operating across a variety of domains.
Collective identity construction in the covid-19 crisis
Authors: Zhang Cun , Liu Guiling , Zhang Shuang
Published: September 2022

Since the pandemic broke out in 2020, China has widely presented the covid crisis in its mass media and actively
constructed collective identity thereof to mobilize medical workers, unify political stances, boost domestic solidarity, and
promote international support. This paper combines the Discourse-Historical Approach and a multimodal perspective to investigate
how the Chinese state-run news agency People’s Daily discursively achieves these purposes on TikTok. A
combination of qualitative and quantitative methods is used to present the high-frequency topoi of justifying the crisis and
referential and predicational strategies of shaping collective identity within, which can fall into four dimensions: positive
Self, negative Self, negative Others, and positive Others.
The linguistic resources can be intensified/mitigated by visual-aural ensembles, which can draw the audience’s attention and
arouse their emotional attachments. This study also summarizes the embedded values in the discourses and situates them in
socio-political contexts.
Integrated assessment of the supply–demand relationship of ecosystem services in the Loess Plateau during 1992–2015
Authors: Wang Dan , Liang Youjia , Peng Shouzhang , Yin Zhangcai , Huang Jiejun
Published: September 2022

Landscape alterations and ecosystem services (ES) are crucial elements that affect the socio-ecological development of ecologically fragile regions. To provide scientific support for the land-use planning and regional ecological restoration to achieve sustainable development goals (SDGs) in the Loess Plateau from 1992 to 2015, this study proposes an integrated assessment framework for assessing the supply – demand match and equilibrium of ES combining potential relationships between landscape alterations, ES, and sustainable development at the county and regional scales. Results show that more than 85% of local counties have a supply – demand mismatch in terms of ecosystem services. Supply – demand distributions for provisioning and supporting services were relatively balanced compared to cultural services, which were imbalanced. Although the overall supply – demand relationship is relatively balanced because of the significant influence of ecological restoration, it shows an increasing trend toward imbalance as human – land conflict is prominent in some regions. SDGs emphasize on specific ES information such as ecosystem conservation, sustainable agriculture, and urban construction. Furtherly, positive impacts from landscape dynamics can improve the supply capacity of the ES and contribute to regional sustainability.
Spatial patterns and influencing factors of intraurban particulate matter in the heating season based on taxi monitoring
Authors: Liu Chong , Hu Yuanman , Chang Yu , Liu Miao , Xiong Zaiping , Chen Tan , Li Chunlin
Published: September 2022

Urbanization has introduced a series of environmental problems worldwide, and particulate matter (PM) is one of the main threats to human health. Due to the lack of high-resolution, large-scale monitoring data, few studies have analyzed the intraurban spatial distribution pattern of PM at a fine scale. In this study, portable air monitors carried by five taxis were used to collect the concentrations of PM
1
, PM
2.5
and PM
10
for five months in Shenyang during the heating season. The results showed that high concentrations of PM were distributed in the suburbs, while relatively low concentration areas were found in the central area. Agricultural, industrial and development zones had higher concentration values among the eight observed types. The PM concentration exhibited strong spatial autocorrelation based on Moran’s I index analysis. Meteorological factors were the most important influencing factors of the three pollutants, and their total contribution rate accounted for more than 80% among the 13 factors according to boosted regression trees analysis. The taxi monitoring method we proposed was a more efficient and feasible method for monitoring urban air pollution and could obtain higher spatial-temporal resolution data at a lower cost to elucidate the region’s dynamic air pollution distribution patterns.
Cyclic spacetimes through singularity scattering maps. Plane-symmetric gravitational collisions
Authors: Le Floch Bruno , LeFloch Philippe G , Veneziano Gabriele
Published: September 2022

We study the plane-symmetric collision of two gravitational waves and describe the global spacetime geometry generated by this collision. We formulate the characteristic initial value problem for the Einstein equations, when Goursat data describing the incoming waves are prescribed on two null hypersurfaces. We construct a global solution representing a cyclic spacetime based on junction conditions associated with a prescribed singularity scattering map, as we call it. This amounts to a detailed analysis of the Goursat and Fuchsian initial value problems associated with singular hyperbolic equations, when junction conditions at interfaces are prescribed. We introduce a partition into monotonicity diamonds (that is, spacetime domains) and we construct the solution by concatenating domains across interfaces of timelike, null, or spacelike type.
On the intrinsically flat cosmological models in a lattice
Authors: Bittencourt Eduardo , Gomes Leandro G , Santos Grasiele B
Published: September 2022

In this manuscript we investigate the intrinsically flat (space-flat) spacetimes as viable cosmological models. We show that they have a natural geometric structure which is suitable to describe inhomogeneous matter distributions forming a periodic pattern throughout the space. We prove theorems for their local representation and for existence and uniqueness of the Einstein’s equations with these periodic boundary conditions. We also find an interesting class of exact solutions, which illustrates the applicability of such spacetimes in cosmology, with an early time behavior close to homogeneity and isotropy and a late time aspect with peaks and voids in the matter distribution.
Analysis of the regimes of feedback effects in quantum dot laser
Authors: Lu Ying , Hu Xiao , Tang Mingchu , Cao Victoria , Yan Jie , Wu Dingyi , Park Jae-Seong , Liu Huiyun , Xiao Xi , Chen Siming
Published: September 2022

We investigated the optical feedback effects on the static and dynamic characteristics of 1.3 μm quantum-dot (QD) Fabry–Pérot laser under reflection from −40 dB up to −8 dB. The onset of coherence collapse is determined as −14 dB from the optical and electrical spectra. Although the degradation in small signal modulation is reported above this critical feedback level, transmission operation with available eye diagram under higher feedback is demonstrated. Under 10 Gb s−1 modulation, there is no obvious degradation in eye diagram regarding the eye shape and extinction ratio up to feedback ratio of −8 dB. The higher feedback tolerance of QD laser under large signal modulation is attributed to the impact of gain compression. This high-speed feedback-resistant operation also indicates that QD laser is a promising light source for isolator-free photonic integrated circuits.
Injection-limited and space charge-limited currents in organic semiconductor devices with nanopatterned metal electrodes
Authors: Buhl Janek , Lüder Hannes , Gerken Martina
Published: September 2022

Charge injection at metal-organic interfaces often limits the electric current in organic light-emitting diodes without additional injection layers. Integrated nanopatterned electrodes may provide a way to overcome this current injection limit by local field enhancements leading to locally space charge-limited currents. We compare electrical characteristics of planar and nanopatterned hole-only devices based on the charge transport material NPB with different thicknesses in order to investigate the nanopattern’s effect on the current limitation mechanism. Integration of a periodic nanograting into the metal electrode yields a current increase of about 1.5–4 times, depending on thickness and operating voltage. To verify the experimental results, we implement a finite element simulation model that solves the coupled Poisson and drift-diffusion equations in a weak form. It includes space charges, drift and diffusion currents, nonlinear mobility, and charge injection at the boundaries. We find in experiment and simulation that the planar devices exhibit injection-limited currents, whereas the currents in the nanopatterned devices are dominated by space charge effects, overcoming the planar injection limit. The simulations show space charge accumulations at the corners of the nanopattern, confirming the idea of locally space charge-limited currents.
A demonstration that frictional heating of Earth is trivial
Authors: Levenson Barton Paul
Published: September 2022

An internet poster recently floated the idea that friction with a recently denser interstellar medium causes global warming. Despite its superficially ridiculous nature, refuting this proposition is an interesting quantitative exercise.
Measuring the magnetic field of a low frequency LC-circuit with phyphox
Authors: Westermann N , Staacks S , Heinke H , Möhrke P
Published: September 2022

In high school, LC(R)-circuits are an integral component of physics education. We propose a new setup for exploring those circuits utilizing the magnetic field sensor of a smartphone in combination with the application phyphox, which reads and displays sensor input. Coils with high inductance and low resistance generate low frequency oscillations which can be visualized without any measuring devices other than a smartphone. The results are very satisfactory, because the resolution of the graph is high and the theoretical values match principal features of the measurements. Also, the setup can be achieved with low-cost components.
Manipulation of antichiral edge state based on modified Haldane model
Authors: Lü Xiao-Long , Yang Jia-En , Chen Huajin
Published: September 2022

Antichiral edge state (AES) was theoretical proposed by Colomés and Franz (2018 Phys. Rev. Lett.
120(8): 086603), which is recently realized in experiment. Under increasing the intensity of the off-resonant circularly polarized light, the AES can be induced as anisotropic, flat types and then anisotropic chiral edge state in zigzag honeycomb nanoribbon. More interestingly, the spin-polarized AESs can be further induced by the antiferromagnetic exchange field and electric field instead of the OPCP light. In particular, according to the propagating direction mismatch, we find the spin-degenerate (spin-polarized) dual propagating channel of the AES can be transformed into the spin-degenerate (spin-polarized) single propagating channel along the upper or lower boundary in topological heterojunction with different edge states. In the switch of the propagating channel, the local bond currents along the outer boundaries are reflected back in the lead and device with bulk states for spin-degenerate and spin polarized cases, respectively. In addition, these propagating channels are also robust against weak normal dephasing effect, which paves diverse platforms to design the topological devices in the future.
On the kinetic energy density functional: The limit of the density derivative order
Authors: Al-Aswad Abdulaziz H , Alharbi Fahhad H
Published: September 2022

Within ‘orbital-free’ density functional theory, it is essential to develop general kinetic energy density (KED), denoted as t(r). This is usually done by empirical corrections and enhancements, gradient expansions, machine learning, or axiomatic approaches to find forms that satisfy physical necessities. In all cases, it is crucial to determine the largest spatial density derivative order, m in, t(r). There have been many efforts to do so, but none have proven general or conclusive and there is no clear guide on how to set m. In this work, we found that, by imposing KED finitude away from V(r) singularities, m = D + 1 for systems of dimension D. This is consistent with observations and provides a needed guide for systematically developing more accurate semilocal KEDs.
2D- PhC based all optical AND, OR and EX-OR logic gates with high contrast ratio operating at C band
Authors: Geerthana S , Syedakbar S , Sridarshini T , Balaji V R , Sitharthan R , Shanmuga Sundar D
Published: September 2022

In this article, photonic crystal (PhC) based all-optical logic gates, namely AND, OR and EX-OR have been explored and their characteristics are reported. Two-dimensional (2D) PhC based logic gates are proposed using a hexagonal lattice with T-shaped structure by incorporating line defects. The total size of the device is 84 µm2 and it operates at a wavelength of 1550 nm (C band). The designed optical logic gates are investigated using 2D finite difference time domain simulators by means of the plane wave expansion method. Parameters, such as response time and contrast ratio of the designed all-optic logic gates, are analyzed. The proposed AND, OR and EX-OR logic gates offer a contrast ratio of 14.48 dB, 14.57 dB and 12.9 dB respectively with, in order, response times of 0.159 ps, 0.168 ps and 0.1672 ps. The designed logic gates work in the third optical window as they are operating at the 1550 nm wavelength. To specify the performance of the proposed logic gates, their field distribution has been determined and is exhibited. The designed logic gates are suitable for use in photonic integrated circuits, all optical computing and optical sensing applications.
Long-term reliability of GFRP reinforcement in concrete structures
Authors: Prokes J , Girgle F , Kostiha V , Bodnarova L , Bezdek O , Stepanek P
Published: September 2022

The article deals with the use of internal FRP (fibre reinforced polymer) reinforcement in concrete structures. In recent decades, the dynamically increasing number of applications in practice yields to the necessity to standardize test procedures, reliably determine short-term and, especially, long-term material characteristics. These are essential to the safe design of this modern material. Due to a lack of knowledge of the long-term behaviour, a substantive conservatism of the available design approaches arises. For this reason, the article deals mainly with the issue of determining the long-term reliability of FRP reinforcement in an aggressive environment with the simultaneous effect of the sustained load. Own findings from the performed long-term tests on the developed glass fibre reinforced polymer bars and experimentally obtained values will be presented.
Possibilities of using numerical modelling to determine the residual load capacity of concrete elements with composite reinforcement after fire
Authors: Prokes J , Rozsypalova I , Cairovic D , Girgle F , Sedlacek O , Danek P
Published: September 2022

During the service life of a structure, a number of phenomena occur that can affect the ability of the concrete structure to continue to perform its function. In the case of concrete load-bearing elements, fire and its effects represent significant influencing factor. Exposure to fire can, among other things, cause a great reduction of material properties of both concrete and reinforcement itself, but also affect their interaction. After a fire incident, it is necessary to assess the residual load capacity of the reinforced concrete elements. As part of the diagnostic work, material samples are usually taken from the structure after a fire. The purpose of the present paper was to investigate whether the experimentally obtained material characteristics can be used to verify the basic behaviour of concrete structures after fire. The structural material properties were used as input values for simplified numerical models of the structures. ATENA Cervenka Consulting software was chosen to construct a numerical model simulating the behaviour of the structural elements after exposure to fire loads. Finally, the effect of high temperatures on the residual load capacity of the beams determined by the numerical approach was compared with the experimental values of the load capacity of the beams after fire. The behaviour of concrete beams of dimensions 100 × 150 × 1800 mm reinforced with composite reinforcement was investigated. The specimens exposed to temperatures of 1000°C were subjected to mechanical bending tests after cooling to determine their residual load capacity.
Possibilities of using fly ash after denitrification to various types of building materials
Authors: Chromkova I , Kubatova D , Bohm P , Cechmanek R , Dzurov M , Kukletova I , Simbera T
Published: September 2022

The paper summarises information gained within the verification of high-temperature fly ashes after the denitrification process. There was an examination of characteristics of fly ashes from various heat sources as well as possibilities of using these types of fly ashes to various types of building applications. An effect on final properties of a building material produced in laboratory or experimental conditions was observed.

Positive results were achieved within the verification of using fly ash to fly ash-cement mixtures. A quality of prepared suspensions was equal to the practically verified one prepared from a fly ash from a powerplant without SNCR. These mixtures after 28 days achieved compressive strengths 8 MPa. Significant increase of strengths in the course of time was recorded. After 90 days compressive strengths achieved values 13-16 MPa and after 1 year even 17-20 MPa. Flexural strengths after 28 days were around 1.5 MPa. This parameter also showed a tendency to increase in time.

Fly ash after denitrification was effective within a preparation of repairing materials based on epoxy resin. For these materials, 50% substitution of natural aggregate with fly ash after denitrification process was proven. Final strength characteristics of the new prepared material outperformed a reference mixture, containing only natural fine-grained aggregate/filler.

A using of fly ash as a compound of filler of alkali-activated systems was also tested. Fly ash after SNCR in the amount of 20 to 60% in combination with fine-milled blast furnace slag and sodium water glass was tested. These materials achieved compressive strengths 50–75 MPa and flexural strengths 6–10 MPa.
Impedance spectroscopy – comparison of dielectric models with a real RC circuit
Authors: Kusak I , Lunak M , Mizerova C , Rovnanik P
Published: September 2022

When studying heterogeneous systems, it is necessary to know properties of all present phases and also structure and behaviour of their mutual interfaces. A discrete model respects atomic structure of bodies (atomic in the sense of particles as carriers of homogeneous properties). It replaces individual atoms with mass points called particles whilst each one of them is a carrier of properties (attributes). The goal of the mathematical formulation of a discrete model is assigning values to particles’ properties. These are displays from a set of particles into a set of attribute values. In general, each one of these displays is a time function. In the paper, we compare a parallel RC circuit with a model outcome. Real electrotechnical components were used: a resistor and a capacitor, which are commonly available in electrical component shops. The accuracy of the value of electrical capacity is below 20 %, the accuracy of the value of electrical resistance is below 5%. The guide value was determined using the Tesla BM595 bridge RLCG meter. R = 9.58 MΩ, C = 10.25 pF – measured at frequency of 1000 Hz. An electrically conductive parallel connection of the resistor and the capacitor was inserted between electrodes and a conductive contact was made.