bluuebunny/crossref_metadata_2025 huggingface dataset:
Technical note: Assessment of radiation measurement devices for the detection of [177Lu]Lu‐labeled radiopharmaceuticals containing [177mLu]Lu‐impurities
Authors: Kupitz Dennis , Einspänner Eric , Wissel Heiko , Hohn Alexander , Kreissl Michael C. , Grosser Oliver S.
Published: October 2022

Background

Nuclear medicine therapies using [177Lu]Lu‐labeled radiopharmaceuticals have increased significantly in recent years. Some of these radiopharmaceuticals contain long‐lived impurities of [177mLu]Lu. Identification of this specific contamination and its quantification is important in different scenarios.

Purpose

In this study, standard measurement hardware used for handling radioisotopes was evaluated for the measurement of [177mLu]Lu and [177Lu]Lu at equilibrium. Device‐specific detection limits (LODs) for [177mLu]Lu were determined according to international standards and then validated.

Methods

The LODs were determined according to the international standard ISO 11929‐1 for [177mLu]Lu for five identical portable contamination monitors (PCMs), a wastewater counter (WWC), and a release counter system (RCS) at different measuring times. Subsequent activity measurements of the defined samples were used to validate the linearity of the measurement instruments down to the LOD for each system.

Results

The average LOD across all PCMs was 0.249 ± 0.009 and 0.129 ± 0.005 Bq/cm2 for 10 and 30 s measurements, respectively. The LODs of WWC varied between 3.3 and 4.7 Bq/L for measurement times of 300 s and 0.8–1.3 Bq/L for 3600 s depending on the energy window studied. The LOD of the RCS depended on the container volume and was 0.08 Bq/g for the 50 L container at 60 s measurement. The measurements for all examined devices were linear down to the LOD (correlation coefficient R ≥ 0.96; coefficient of determination R2 ≥ 0.92).

Conclusions

All investigated measuring instruments (PCM, WWC, RCS) were suitable for the determination of [177mLu]Lu at equilibrium, and their specific LODs were determined. Based on the measurements performed, activity is overestimated; however, this is tolerable because assumptions and measurements in the context of radiation protection should be conservative.
Intravesical IR‐780 instillation prevents radiation cystitis by protecting urothelial integrity
Authors: Li Jinjin , Shen Chongxing , Qiu Heping , Wang Jianwu , Yue Xiaofeng , Dai Linyong , Huang Yuandi , Li Tong , Fang Qiang , Zhi Yi , Shi Chunmeng , Li Weibing
Published: October 2022

Purpose

To explore an efficient preventive strategy for radiation cystitis.

Methods

We instilled IR‐780 into the bladders of rats 1 h before bladder irradiation, and its bio‐distribution was observed at different times. Bladders were then examined for pathogenic alterations and inflammation levels by day 3 and week 12 postirradiation, and the functional characteristics of the bladder were tested via cystometry by week 12. Human uroepithelial sv‐huc‐1 cells were used to determine the effect of IR‐780 on cell viability, regardless of irradiation. We measured the intracellular levels of oxidative stress, DNA damage, apoptosis proportion, and the expression of antioxidant proteases and apoptotic caspases in IR‐780 pretreated cells after radiation.

Results

IR‐780 is localized in the urothelium after intravesical instillation in vivo. Ionizing radiation could induce acute impairment of the bladder urothelium and inflammation in the bladder on day 3. Fibrosis of the irradiated bladder progressed and eventually affected voiding function at 12 weeks. Treatment with IR‐780 before irradiation ameliorated these changes. In vitro, IR‐780 protected against cell viability and apoptosis of sv‐huc‐1 cells after irradiation. Additionally, IR‐780 may assist in eliminating reactive oxygen species and repairing irradiation‐induced DNA damage.

Conclusion

Our data indicate that IR‐780 can be used before irradiation to prevent acute urinary mucosal injury and late bladder dysfunction. Moreover, early urothelial impairment plays a significant role in radiation cystitis development.
On the SAV‐DG method for a class of fourth order gradient flows
Authors: Liu Hailiang , Yin Peimeng
Published: October 2022

For a class of fourth order gradient flow problems, integration of the scalar auxiliary variable (SAV) time discretization with the penalty‐free discontinuous Galerkin (DG) spatial discretization leads to SAV‐DG schemes. These schemes are linear and shown unconditionally energy stable. However, the reduced linear systems are rather expensive to solve due to the dense coefficient matrices. In this paper, we provide a procedure to pre‐evaluate the auxiliary variable in the piecewise polynomial space. As a result the computational complexity of reduces to when exploiting the conjugate gradient (CG) solver. This hybrid SAV‐DG method is more efficient and able to deliver satisfactory results of high accuracy. This was also compared with solving the full augmented system of the SAV‐DG schemes.
A fourth‐order accurate numerical method for the distributed‐order Riesz space fractional diffusion equation
Authors: Chen Xuejuan , Chen Jinghua , Liu Fawang , Sun Zhi‐zhong
Published: October 2022

In this article, a novel fourth‐order accurate difference method is derived for the distributed‐order Riesz space fractional diffusion equation in one‐dimensional (1D) and two‐dimensional (2D) cases, respectively. First, the distributed integral terms are discretized by using the Simpson quadrature rule into the multi‐term Riesz space fractional diffusion equations. Then, a fourth‐order accurate difference scheme is presented to approximate the multi‐term Riesz fractional diffusion equations. Moreover, the proposed difference schemes are proved to be unconditionally stable and convergent in norm for both 1D and 2D cases. Finally, numerical experiments are given to verify the efficiency of the schemes.
One‐Pot Electrochemical Synthesis of Citric Acid Functionalized Iron Oxide Magnetic Nanoparticles for Congo Red Adsorption
Authors: Pawar Aditya Amrut , Kumar Ravi , Sharma Shilpa , Satyanarayana Tulasi
Published: October 2022

Azo dyes, like Congo red (CR), are persistent contaminants that cause detrimental consequences on living organisms in various habitats. In the present study, a novel and facile one‐pot citric acid functionalized iron oxide magnetic nanoparticles (Fe3O4@CA NPs) through an electrochemical method are synthesized and characterized for adsorbing CR dye present in an aqueous solution is reported. The influence of various factors on the adsorption of CR dye, namely pH of the CR solution, Fe3O4@CA NPs concentration, initial CR dye concentration, contact time, temperature, and agitation speed, are examined. The adsorption isotherms and kinetic studies for CR adsorption on Fe3O4@CA NPs are also investigated. The equilibrium results correspond well to the Langmuir isotherm having maximum dye uptake of 46.948 mg g−1, while the adsorption follows the pseudo‐second‐order kinetics model. The adsorption process appears to be spontaneous and endothermic, according to the thermodynamic parameters. The mechanism of CR adsorption on Fe3O4@CA NPs is also suggested. The synthesized nanoadsorbent shows more than 90% recyclability during five consecutive adsorption–desorption cycles. The simple and cost effective synthesis, high adsorption capacity, and recyclable nature of Fe3O4@CA NPs suggest the potential to eliminate CR from aqueous sources.
DomainMapper: Accurate domain structure annotation including those with non‐contiguous topologies
Authors: Manriquez‐Sandoval Edgar , Fried Stephen D.
Published: October 2022

Automated domain annotation is an important tool for structural informatics. These pipelines typically involve searching query sequences against hidden Markov model (HMM) profiles, yielding matches to profiles for various domains. However, domain annotation can be ambiguous or inaccurate when proteins contain domains with non‐contiguous residue ranges, and especially when insertional domains are hosted within them. Here, we present DomainMapper, an algorithm that accurately assigns a unique domain structure annotation to a query sequence, including those with complex topologies. We validate our domain assignments using the AlphaFold database and confirm that non‐contiguity is pervasive (10.74% of all domains in yeast and 4.52% in human). Using this resource, we find that certain folds have strong propensities to be non‐contiguous or insertional across the Tree of Life. DomainMapper is freely available and can be ran as a single command‐line function.
Ultrasound‐based radiomics score for pre‐biopsy prediction of prostate cancer to reduce unnecessary biopsies
Authors: Ou Wei , Lei Jiahao , Li Minghao , Zhang Xinyao , Liang Ruiming , Long Lingli , Wang Changxuan , Chen Lingwu , Chen Junxing , Zhang Junlong , Wang Zongren
Published: October 2022

Background

Patients undergoing prostate biopsies (PBs) suffer from low positive rates and potential risk for complications. This study aimed to develop and validate an ultrasound (US)‐based radiomics score for pre‐biopsy prediction of prostate cancer (PCa) and subsequently reduce unnecessary PBs.

Methods

Between December 2015 and March 2018, 196 patients undergoing initial transrectal ultrasound (TRUS)‐guided PBs were retrospectively enrolled and randomly assigned to the training or validation cohort at a ratio of 7:3. A total of 1044 radiomics features were extracted from grayscale US images of each prostate nodule. After feature selection through the least absolute shrinkage and selection operator (LASSO) regression model, the radiomics score was developed from the training cohort. The prediction nomograms were developed using multivariate logistic regression analysis based on the radiomics score and clinical risk factors. The performance of the nomograms was assessed and compared in terms of discrimination, calibration, and clinical usefulness.

Results

The radiomics score consisted of five selected features. Multivariate logistic regression analysis demonstrated that the radiomics score, age, total prostate‐specific antigen (tPSA), and prostate volume were independent factors for prediction of PCa (all p < 0.05). The integrated nomogram incorporating the radiomics score and three clinical risk factors reached an area under the curve (AUC) of 0.835 (95% confidence interval [CI], 0.729–0.941), thereby outperforming the clinical nomogram which based on only clinical factors and yielded an AUC of 0.752 (95% CI, 0.618–0.886) (p = 0.04). Both nomograms showed good calibration. Decision curve analysis indicated that using the integrated nomogram would add more benefit than using the clinical nomogram.

Conclusion

The radiomics score was an independent factor for pre‐biopsy prediction of PCa. Addition of the radiomics score to the clinical nomogram shows incremental prognostic value and may help clinicians make precise decisions to reduce unnecessary PBs.
Governing dynamics and preferential binding of the AXH domain influence the aggregation pathway of Ataxin‐1
Authors: Tammara Vaishnavi , Das Atanu
Published: October 2022

The present state of understanding the mechanism of Spinocerebellar Ataxia‐1, a fatal neurodegenerative disease linked to the protein Ataxin‐1 (ATXN1), is baffled by a set of self‐contradictory, and hence, inconclusive observations. This fallacy poses a bottleneck to the effective designing of curable drugs as the field is currently missing the specific druggable site. To understand the fundamentals of pathogenesis, we tried to decipher the intricacies of the extremely complicated landscape by targeting the relevant species that supposedly dictate the structure–function paradigm. The atomic‐level description and characterization of the dynamism of the systems reveal the existence of structural polymorphism in all the leading stakeholders of the overall system. The very existence of conformational heterogeneity in every species creates numerous possible combinations of favorable interactions because of the variability in segmental cross‐talks and hence claims its role in the choice of routes between functional activity and dysfunctional disease‐causing aggregation. Despite this emergent configurational diversity, there is a common mode of operative intermolecular forces that dictates the extent of stability of all the multimeric complexes due to the localized population of a specific type of residue. The present research proposes a dynamic switch mechanism between aggregability and functional activity, based on the logical interpretation of the estimated variables, which is practically dictated by the effective concentration of the interacting species involved in the cell.
Conjugates of adenosine mimetics and arginine‐rich peptides serve as inhibitors and fluorescent probes but not as long‐lifetime photoluminescent probes for protein arginine methyltransferases
Authors: Lavogina Darja , Nasirova Naila , Sõrmus Tanel , Tähtjärv Taavo , Enkvist Erki , Viht Kaido , Haljasorg Tõiv , Herodes Koit , Jaal Jana , Uri Asko
Published: October 2022

The conjugates of an adenosine mimetic and oligo‐l‐arginine or oligo‐d‐arginine (ARCs) were initially designed in our research group as inhibitors and photoluminescent probes targeting basophilic protein kinases. Here, we explored a panel of ARCs and their fluorescent derivatives in biochemical assays with members of the protein arginine methyltransferase (PRMT) family, focusing specifically on PRMT1. In the binding/displacement assay with detection of fluorescence anisotropy, we found that ARCs and arginine‐rich peptides could serve as high‐affinity ligands for PRMT1, whereas the equilibrium dissociation constant values depended dramatically on the number of arginine residues within the compounds. The fluorescently labeled probe ARC‐1081 was displaced from its complex with PRMT1 by both S‐adenosyl‐l‐methionine (SAM) and S‐adenosyl‐l‐homocysteine (SAH), indicating binding of the adenosine mimetic of ARCs to the SAM/SAH‐binding site within PRMT1. The ARCs that had previously shown microsecond‐lifetime photoluminescence in complex with protein kinases did not feature such property in complex with PRMT1, demonstrating the selectivity of the time‐resolved readout format. When tested against a panel of PRMT family members in single‐dose inhibition experiments, a micromolar concentration of ARC‐902 was required for the inhibition of PRMT1 and PRMT7. Overall, our results suggest that the compounds containing multiple arginine residues (including the well‐known cell‐penetrating peptides) are likely to inhibit PRMT and thus interfere with the epigenetic modification status in complex biological systems, which should be taken into consideration during interpretation of the experimental data.
A note on an average run length calculation for the EWMA and other charts
Authors: Haq Abdul , Woodall William H.
Published: October 2022

In the last decade numerous papers have appeared in the statistical process monitoring literature where the in‐control and out‐of‐control average run length (ARL) profiles of the exponentially weighted moving average chart, and some of its variants, have been approximated under the assumption that the signal event can be represented by a sequence of independent Bernoulli random variables. In this short note we show that these approximations, presented in the literature as being exact, can be very inaccurate when compared with the true ARL values. Moreover, the use of these poor ARL approximations has led to many flawed articles, which should be either corrected or retracted.
Pathophysiology of polycystic ovary syndrome revisited: Current understanding and perspectives regarding future research
Authors: Harada Miyuki
Published: October 2022

Background

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder among reproductive‐age women and has lifelong effects on health.

Methods

In this review, I discuss the pathophysiology of PCOS. First, I summarize our current understanding of the etiology and pathology of PCOS, then, discuss details of two representative environmental factors involved in the pathogenesis of PCOS. Finally, I present perspectives regarding the directions of future research.

Main findings

The pathophysiology of PCOS is heterogeneous and shaped by the interaction of reproductive dysfunction and metabolic disorders. Hyperandrogenism and insulin resistance exacerbate one another during the development of PCOS, which is also affected by dysfunction of the hypothalamus‐pituitary‐ovarian axis. PCOS is a highly heritable disorder, and exposure to certain environmental factors causes individuals with predisposing genetic factors to develop PCOS. The environmental factors that drive the development of PCOS pathophysiology make a larger contribution than the genetic factors, and may include the intrauterine environment during the prenatal period, the follicular microenvironment, and lifestyle after birth.

Conclusion

On the basis of this current understanding, three areas are proposed to be subjects for future research, with the ultimate goals of developing therapeutic and preventive strategies and providing appropriate lifelong management, including preconception care.
Formation control of nonholonomic mobile robots with inaccurate global positions and velocities
Authors: Li Li , Kuang Changgen , Xia Yuanqing , Qiang Jiaping
Published: October 2022

In this article, leader‐following formation control is investigated for nonholonomic mobile robots with inaccurate measurements of global positions and velocities. In many existing results, the leader robot's velocities are assumed to be precisely measured and transmitted to follower robots, and unmodeled parts of the kinematic model caused by inaccurate global position are often ignored. First, an error‐based extended state observer (EBESO) for each robot is designed to counteract influence of the inaccurate global positions and velocities in real time. Then, an EBESO‐based formation controller without the leader robot's velocities is proposed to guarantee the accurate formation tracking performances. Furthermore, both convergence of the EBESO and stability analysis of the closed‐loop error system are provided, respectively. The superiority of the proposed method is verified and illustrated by experiments.
Stabilizing a class of nonlinear parameter‐varying systems using interval observer based on a piecewise framework
Authors: Faramin Mostafa , Rezaie Behrooz , Rahmani Zahra
Published: October 2022

This article addresses an interval observer‐based control for stabilizing a class of nonlinear parameter‐varying systems with noisy output by designing a switching surface. An input‐dependent interval observer is firstly developed to estimate the lower and upper bounds of the states. Next, a switching‐based controller is designed to stabilize the interval observer which implies the stability of the main parameter‐varying system. The developed stabilizing switching surfaces are designed based on the outputs of the main system and the bounds of the states of the observer. By choosing an appropriate piecewise Lyapunov function, the closed‐loop stability analysis of the interval observer system leads to a set of linear matrix inequalities including stability and Metzler constraints, simultaneously. The effectiveness of the proposed method is verified using the simulation results.
Dynamics between environmental taxes and ecological sustainability: Evidence from top‐seven green economies by novel quantile approaches
Authors: Ullah Sami , Luo Rundong , Adebayo Tomiwa Sunday , Kartal Mustafa Tevfik
Published: October 2022

Regulations and taxes are considered essential drivers for climate change policies and improving ecological quality. The prior research primarily relies on regulatory or non‐economic measures to ensure ecological sustainability, while the role of market‐based or economic measures in ecological sustainability is yet to be investigated. Hence, realizing the need for policy shift, this study is an effort to determine the dynamics between environmental taxes and ecological sustainability for the period between 1995/Q1 and 2018/Q4 using data of top‐seven green economies by employing novel Quantile‐on‐Quantile (QQ) regression approach. The outcomes from the QQ approach indicate the mixed and asymmetric impact of the environmental taxes on ecological sustainability in sample countries over different quantiles. However, a higher ecological promoting impact is observed at upper‐middle quantiles in most of the sample countries. The robustness of the study's results is validated by Quantile Regression (QR) approach and the nonparametric quantile causality test. The study's outcomes provide significant suggestions to formulate policies for helping sample economies to accomplish Sustainable Development Goals (SDGs) 7 and 13 while ensuring ecological sustainability.
Self‐Propelled Structural Color Cylindrical Micromotors for Heavy Metal Ions Adsorption and Screening
Authors: Shang Yixuan , Cai Lijun , Liu Rui , Zhang Dagan , Zhao Yuanjin , Sun Lingyun
Published: October 2022

Water contamination resulting from heavy metal ions (HMIs) poses a severe threat to public health and the ecosystem. Attempts are tending to develop functional materials to realize efficient and intelligent adsorption of HMIs. Herein, self‐propelled structural color cylindrical micromotors (SCCMs) with reversible HMIs adsorption capacity and self‐reporting property are presented. The SCCMs are fabricated by using platinum nanoparticles (Pt NPs) tagged responsive hydrogel of carboxymethyl chitosan (CMC) and polyacrylamide (PAM) to asymmetrically replicate tubular colloidal crystal templates (TCCTs). Owing to the self‐propelled motion of the SCCMs, the enhancive ion–motor interactions bring significantly improved decontamination efficiency. Moreover, it is demonstrated that the SCCMs can realize quick and naked‐eye‐visible self‐reporting during the adsorption/desorption process based on their responsive structure color variation and superior adsorption capacity. Thus, it is anticipated that such intelligent SCCMs can significantly facilitate the evolution of sensing assays and diverse environmental fields.
Emerging Applications of Synchrotron Radiation X‐Ray Techniques in Single Atomic Catalysts
Authors: Song Zhongxin , Li Junjie , Davis Kieran Doyle , Li Xifei , Zhang Jiujun , Zhang Lei , Sun Xueliang
Published: October 2022

Single atom catalysts (SACs) can achieve a maximum atom utilization efficiency of 100%, which provides significantly increased active sites compared with traditional catalysts during catalytic reactions. Synchrotron radiation technology is an important characterization method for identifying single‐atom catalysts. Several types of internal information, such as the coordination number, bond length and electronic structure of metals, can all be analyzed. This review will focus on the introduction of synchrotron radiation techniques and their applications in SACs. First, the fundamentals of synchrotron radiation and the corresponding techniques applied in characterization of SACs will be briefly introduced, such as X‐ray absorption near edge spectroscopy and extended X‐ray absorption fine structure spectroscopy and in situ techniques. The detailed information obtained from synchrotron radiation X‐ray characterization is described through four routes: 1) the local environment of a specific atom; 2) the oxidation state of SACs; 3) electronic structures at different orbitals; and 4) the in situ structure modification during catalytic reaction. In addition, a systematic summary of synchrotron radiation X‐ray characterization on different types of SACs (noble metals and transition metals) will be discussed.
Facile Fabrication of N‐Doped K2Nb2O6 Nanocrystals with Defective Pyrochlore Structure for Improved Visible‐Light Photocatalytic Hydrogen Production
Authors: Wang Jinyuan , Wang Jinhu , Shi Run , Zhou Chao , Zhang Tierui
Published: October 2022

Semiconductor‐based photocatalytic water splitting is one of the effective ways for future hydrogen (H2) production. However, the wide bandgap of most semiconductors severely limits the solar spectral absorption range, which seriously hinders their practical applications. Herein, porous N‐doped K2Nb2O6 nanocrystals with defective pyrochlore structure are rationally designed to extend the absorption range from ultraviolet to visible region around 550 nm by NH3 heat treatment. The obtained 6N–K2Nb2O6 shows the highest visible‐light activity with an H2 evolution rate of 20.4 μmol h−1 g−1. More detailed exploration demonstrates that NH3 heat treatment can promote the substitutional nitrogen doping in K2Nb2O6 crystals while accompanied by the formation of oxygen vacancies or Nb4+ species. The hybridization of N 2p and O 2p orbitals in the valence band (VB) of the nitrogen‐doped K2Nb2O6 makes the VB maximum move more negatively, whereas the conduction band minimum shifted more positively due to the role of defective Nb4+ species. Such a synergistic effect endows the samples with visible‐light absorption and greatly enhances charge separation and transfer efficiency, resulting in the excellent H2 production performance. This study provides additional insights into the understanding of the effect of nitrogen doping on photocatalysts with excellent visible‐light‐driven photocatalytic activity.
Experimental investigation of a locally prestressed precast concrete wall
Authors: Zhang Yong , Qing Yuan , Wang Chun‐Lin , Zeng Bin
Published: October 2022

The posttensioned (PT) tendons in a prestressed precast wall (PPW) may suffer yielding or damage under rare earthquake events, increasing the potential demand for their maintenance and renewal. A locally PPW (LPPW) with PT tendons arranged only in the lower stories was developed in this article to facilitate the replacement of the PT tendons. Quasi‐static tests were conducted to investigate the seismic performance of the LPPW with and without additional energy dissipaters. The test results demonstrated that the LPPW featured a stable hysteretic response and an excellent self‐centering capacity. The dissipaters effectively improved the energy dissipation capacity of the LPPW and preserved its self‐centering capacity. Numerical studies were further performed to address the influence of the layout of the PT tendons and dissipaters. The numerical results showed that reducing the height of the upper anchorage points of the PT tendons could increase the bearing capacity and postyielding stiffness of the LPPW. The concrete contact force at the base joint could be reduced by about 40% by moving the dissipaters from center to edge regions of the cross‐section of the wall.
Time‐dependent seismic fragility curves for existing RC core‐wall buildings exposed to corrosion
Authors: Michelini Elena , Belletti Beatrice , Franceschini Lorenzo , Martinelli Enzo
Published: October 2022

This work aims at investigating the seismic response of existing reinforced concrete core‐wall buildings with corroded bars erected in the marine environments, with the main focus on the dependency of seismic fragility curves on aging and degradation effects caused by environmental actions. The structural capacity is predicted by nonlinear finite‐element analyses, where the effect of chloride corrosion is implemented within the framework of PARC_CL_2.1 crack model. The proposed methodology is applied to a pre‐code six‐story reinforced concrete (RC) building with moment‐resisting (MR) frames and an internal core assumed as a testbed. For a given exposure class, pushover analyses are performed for different ages of the building. Time‐dependent fragility curves are then obtained through a procedure based on incremental static analysis. Different corrosion scenarios are assessed by considering deterioration effects applied either on the sole RC walls or on both walls and columns. The obtained results highlight that time‐dependent fragility curves are strongly affected by corrosion, therefore the date of construction should be considered in seismic risk mapping, not only for evaluating the effect of obsolete standard codes used in the design but also in terms of damage induced by aging and deterioration.
Reliability‐based design of transmission and anchorage lengths in prestressed concrete elements
Authors: Faleschini Flora , Hofer Lorenzo , Belluco Sergio , Pellegrino Carlo
Published: October 2022

This work proposes new reliability‐based formulations for the design of transmission and anchorage lengths in prestressed reinforced concrete, starting from the equations discussed and proposed by fib TG2.5 “Bond and Material Models.” To this end, an extensive experimental dataset with more than 900 results was collected from the scientific literature. Then, two deterministic models were proposed, one for the transmission and one for the anchorage length. For each, model uncertainty was evaluated, and then a probabilistic calibration of their distributions was carried out, separating the cases when sudden or gradual prestress release was applied. Then, probabilistic models were developed for transmission and anchorage length evaluation, depending on the prestress release method: from them, it was possible to evaluate suitable coefficients to target varying reliability indexes. Particularly, two design situations were considered, for transverse stresses verification at the Serviceability Limit State (SLS) and shear and anchorage verification at the Ultimate Limit State (ULS). Lastly, the reliability of current deterministic models was verified.
Relation between half‐cell and fuel cell activity and stability of FeNC catalysts for the oxygen reduction reaction
Authors: Scharf Janik , Kübler Markus , Gridin Vladislav , Wallace William David Zacharias , Ni Lingmei , Paul Stephen Daniel , Kramm Ulrike Ingrid
Published: October 2022

FeNC catalysts are promising substitutes of platinum‐type catalysts for the oxygen reduction reaction (ORR). While previous research disclosed that high pyrolysis temperatures are required to achieve good stability, it was identified that a trade‐off needs to be made regarding the active site density. The central question is, if a good stability can also be reached at milder pyrolysis conditions but longer duration retaining more active sites, while enabling the defect‐rich carbon to heal during a long residence time? To address this, a variation of pyrolysis temperatures and durations is used in FeNC fabrication. Carbon morphology and iron species are characterized by Raman spectroscopy and Mössbauer spectroscopy, respectively. Fuel cell (FC) activity and stability data are acquired. The results are compared to ORR activity and selectivity data from rotating ring disc electrode experiments and resulting durability in accelerated stress tests mimicking the load cycle and start‐up and shut‐down cycle conditions. It is discussed how pyrolysis temperature and duration affect FC activity and stability. But, more important, the results connect the pyrolysis conditions to the required accelerated stress test protocol combination to enable a prediction of the catalyst stability in fuel cells.
Artificial intelligence‐enhanced skin‐like sensors based on flexible nanogenerators
Authors: Wang Yiqian , Tan Puchuan , Wu Yuxiang , Luo Dan , Li Zhou
Published: October 2022

Artificial intelligence‐enhanced skin‐like sensors based on flexible nanogenerators have been widely used in physiological signal acquisition, artificial organ, sensory simulation, human movement status recognition, and other biomedical related fields due to their excellent biocompatibility, comfortable wearing experience, high sensing accuracy, and low power consumption. In this paper, the working principle, evolution process, and several established general strategies of artificial intelligence‐enhanced skin‐like sensors are summarized in detail. More importantly, this paper further reviews several recent important advances on artificial intelligence enhanced skin‐like sensor, and systematically analyzes and compares these works according to their principles and application directions. In the discussion section, we also list the current concerns of stress adaptation, stretchability–conductivity, algorithm optimization, function integration, and propose potential solutions to these problems. We hope that the deep integration of artificial intelligence and flexible nanogenerators can bring more enlightenment to the progress of biomedical engineering in the future.
Introduction: Trends, Puzzles, and Hopes for the Future of Healthcare
Authors: Ehsani Sepehr , Glauner Patrick , Plugmann Philipp , Thieringer Florian M.
Published: October 2022

This book is being published at a time when the collective attention of the world has been focused, for more than 2 years, on the coronavirus pandemic. The interrelatedness of various facets of biomedicine (whether scientific, societal, political, legal, or cultural) has been vividly illustrated to health practitioners, researchers, and the public at large—often on a very personal level. It is now manifestly obvious to many that planning for the future of clinical and experimental medicine is a must. Although the task of predicting the exact trajectory of any profession might be in vain, it is essential that one at least looks at past and current trends in order to envision future scenarios and plan for them. We can thus shape our expectations about how the various threads of biomedicine could develop; these could then inform our preparedness.
New Horizons in Studying the Cellular Mechanisms of Alzheimer’s Disease
Authors: Ehsani Sepehr
Published: October 2022

Following an analysis of the state of investigations and clinical outcomes in the Alzheimer’s research field, I argue that the widely accepted ‘amyloid cascade’ mechanistic explanation of Alzheimer’s disease appears to be fundamentally incomplete. In this context, I propose that a framework termed ‘principled mechanism’ (PM) can help remedy this problem. First, using a series of five ‘tests’, PM systematically compares different components of a given mechanistic explanation against a paradigmatic set of criteria and hints at various ways of making the mechanistic explanation more ‘complete’. I will demonstrate these steps using the amyloid explanation, highlighting its missing or problematic mechanistic elements. Second, PM makes an appeal for the discovery and application of ‘biological principles’ that approximate ceteris paribus generalisations or laws and are operative at the level of a biological cell. Although thermodynamic, evolutionary, ecological and other laws or principles from chemistry and the broader life sciences could inform them, biological principles should be considered ontologically unique. These principles could augment different facets of the mechanistic explanation but also allow furtherindependentnomological explanation of the phenomenon. Whilst this overall strategy can be complementary to certain ‘new mechanist’ approaches, an important distinction of the PM framework is its equal attention to the explanatory utility of biological principles. Lastly, I detail two hypothetical biological principles and show how they could each inform and improve the potentially incomplete mechanistic aspects of the amyloid explanation and how they could provide independent explanations for the cellular features associated with Alzheimer’s disease.
Once More with Feeling: Emotions in Multimodal Learning Analytics
Authors: Kubsch Marcus , Caballero Daniela , Uribe Pablo
Published: October 2022

The emotions that students experience when engaging in tasks critically influence their performance and many models of learning and competence include assumptions about affective variables and respective emotions. However, while researchers agree about the importance of emotions for learning, it remains challenging to connect momentary affect, i.e., emotions, to learning processes. Advances in automated speech recognition and natural language processing (NLP) allow real time detection of emotions in recorded language. We use NLP and machine learning techniques to automatically extract information about students’ motivational states while engaging in the construction of explanations and investigate how this information can help more accurately predict students’ learning over the course of a 10-week energy unit. Our results show how NLP and ML techniques allow the use of different modalities of the same data in order to better understand individual differences in students’ performances. However, in realistic settings, this task remains far from trivial and requires extensive preprocessing of the data and the results need to be interpreted with care and caution. Thus, future research is needed before these methods can be deployed at scale.
On the positivity of Coon amplitude in D = 4
Authors: Chakravarty Joydeep , Maity Pronobesh , Mishra Amiya
Published: October 2022

Abstract

The Coon amplitude is the unique solution to duality constraints with logarithmic Regge trajectories. A striking feature of this solution is that it interpolates between the Veneziano amplitude and a scalar particle amplitude. However, an analytic proof of unitarity of the amplitude is not yet known. In this short note, we explicitly compute the partial wave coefficients on the leading Regge trajectory in D = 4. We find that these coefficients always remain positive, even though their magnitude decreases with spin. Since the coefficients on the subleading trajectories are observed to be larger than those on the leading ones, our result indicates the positivity of the full Coon amplitude in D = 4.
Perturbative calculations of gravitational form factors at large momentum transfer
Authors: Tong Xuan-Bo , Ma Jian-Ping , Yuan Feng
Published: October 2022

Abstract

We perform a perturbative QCD analysis of the gravitational form factors (GFFs) of nucleon at large momentum transfer. We derive the explicit factorization formula of the GFFs in terms of twist-3 and twist-4 light-cone distribution amplitudes of nucleon. Power behaviors for these GFFs are obtained from the leading order calculations. Numeric results of the quark and gluon contributions to various GFFs are presented with model assumptions for the distribution amplitudes in the literature. We also present the perturbative calculations of the scalar form factor 〈P′| F2| P〉 for pion and proton at large momentum transfer.
Effect of spacetime dimensions on quantum entanglement between two uniformly accelerated atoms
Authors: Yan Jiatong , Zhang Baocheng
Published: October 2022

Abstract

We investigate the entanglement dynamics for a quantum system composed of two uniformly accelerated Unruh-DeWitt detectors in different spacetime dimensions. It is found that the range of parameters in which entanglement can be generated is shrunk and the amount of generated entanglement is also decreased with the increasing spacetime dimension, by calculating the evolution of two-atom states using the method for open quantum systems. We study the entanglement evolution between two accelerated atoms for different initial two-atom states, and the influence of corresponding spacetime dimensions for every initial state is discussed. When the spacetime dimensions increase, the change of entanglement becomes slower with time. The influence of spacetime dimensions on the change of entanglement also expands to the case of the massive field. The time delay for entanglement generation is shown in different spacetime dimensions. In particular, entanglement decreases more quickly with the increasing spacetime dimensions compared with that in the case of the massless field. The recently found anti-Unruh effect is discussed, and a novel and interesting phenomenon is found that the Unruh effect in small spacetime dimensions can become the anti-Unruh effect in large spacetime dimensions with the same parameters.
Quantum phases of 4d SU(N) $$ \mathcal{N} $$ = 4 SYM
Authors: Cabo-Bizet Alejandro
Published: October 2022

Abstract

It is argued that 4d SU(N) $$ \mathcal{N} $$
N
= 4 SYM has an accumulation line of zero-temperature topologically ordered phases. Each of these phases corresponds to N bound states charged under electromagnetic $$ {\mathbb{Z}}_N^{(1)} $$

ℤ
N

1

one-form symmetries. Each of the N bound states is made of two Dyonic flux components each of them extended over a two dimensional surface. They are localized at the fixed loci of a rotational action, and are argued to correspond to conformal blocks (or primaries) of an SU(N)1 WZNW model on a two-torus.
Can neural networks predict steady annual cycles of marine ecosystems?
Authors: Slawig Thomas , Pfeil Markus
Published: October 2022

We used artificial neural networks to replace the complete spin-up procedure that computes a steady annual cycle of a marine ecosystem driven by ocean transport. The networks took only the few biogeochemical model parameters and attempted to predict the spatially distributed concentrations of the ecosystem, in this case only nutrients, for one time point of the annual cycle. The ocean circulation was fixed for all parameters. Different network topologies, sparse networks, and hyperparameter optimization using a genetic algorithm were used. This showed that all studied networks can produce a distribution that is point-wise close to the original spin-up result. However, these predictions were far from being annually periodic, such that a subsequent spin-up was necessary. In this way, the overall runtime of the spin-up could be reduced by 13% on average. It is debatable whether this procedure is useful for the generation of initial values, or whether simpler methods can achieve faster convergence.
Randomized comparison of 4.5/6 Fr versus 6/7.5 Fr ureteroscopes for laser lithotripsy of lower/middle ureteral calculi: towards optimization of efficacy and safety of semirigid ureteroscopy
Authors: Omar Mohamed , Dorrah Mohammed , Khalifa Ahmed , El Sherif Eid , Sayedahmed Khalid , Ghazwani Yahya , Noureldin Yasser A.
Published: October 2022

Background and purpose

To compare 4.5/6 Fr versus 6/7.5 Fr semirigid ureteroscopes in terms of safety and efficacy in adult non-obese patients with middle or lower ureteric stones.

Materials and methods

A total of 198 patients with middle/lower ureteric stone and a BMI ≤ 30 kg/m2 were recruited. Patients were randomized according to the size of ureteroscope into two groups: group 1 where a 4.5/6 Fr semi-rigid ureteroscope was used, and group 2 where a 6/7.5 Fr semi-rigid ureteroscope was used. Patient’s demographic, stone characteristics, intraoperative and postoperative outcomes including stone-free rate (SFR) and complications were compared.

Results

Preoperative characteristics in terms of age, sex, BMI, and stone location, side, size, and HU were comparable between both groups (p values > 0.05). The overall SFR was significantly higher in group 1 (0.004). Balloon dilatation was not required in all patients of group-1 compared with 33% of group-2 (p = 0.0001). The JJ stent was required in 10% of group-1 compared with 30% of group-2 (p = 0.0004). Failure to reach the stone due to tight ureter occurred in 8% of group 2 (p = 0.003), respectively. Traxer’s grade 1 ureteral injury occurred in 2% of group-1 versus 14% of group-2 (p = 0.001). Consequently, hematuria was significantly lower in group-1 (1% vs. 8%; p = 0.01), respectively. The hospital stay < 9 h was significantly higher in group 1 (p = 0.0001).

Conclusions

The 4.5/6 Fr semi-rigid Ureteroscope was associated with significantly higher SFR and shorter hospital stay, with lower ureteral injury, fewer double-J stenting, and without the need for intraoperative balloon dilatation for the ureter.
A test for normality and independence based on characteristic function
Authors: Ejsmont Wiktor , Milošević Bojana , Obradović Marko
Published: October 2022

In this article we prove a generalization of the Ejsmont characterization (Ejsmont in Stat Probab Lett 114:1–5, 2016) of the multivariate normal distribution. Based on it, we propose a new test for independence and normality. The test uses an integral of the squared modulus of the difference between the product of empirical characteristic functions and some constant. Special attention is given to the case of testing for univariate normality in which we derive the test statistic explicitly in terms of Bessel function and explore asymptotic properties. The simulation study also includes the cases of testing for bivariate and trivariate normality and independence, as well as multivariate normality. We show the quality performance of our test in comparison to some popular powerful competitors. The practical application of the proposed normality and independence test is discussed and illustrated using a real dataset.
Evaluation of Bentonite Application for the Abandonment of Deep Geo-energy Wells
Authors: Corina A. N. , Wollenweber J. , Fischer H. , van der Valk K. , Castelein K. , Moghadam A. , Heerens G-J
Published: October 2022

Hydrated bentonite is considered an alternative subsurface sealing/plugging material for deep geo-energy wells. However, the knowledge related to this application and the corresponding properties of bentonite is still lacking. This includes the mechanical properties at the interface of bentonite plugs with the adjacent materials (surrounding rock or casing steel) and the mechanical stability of plugs under downhole in-situ conditions. In this work, we performed experiments investigating the interface shear properties and shear strength of a bentonite plug under various settings for deep geo-energy applications, such as hydrocarbon and geothermal wells. The interface’s shear properties against various adjacent materials and fluid conditions were characterized. The influence of chemical exposure, the salinity of the curing fluid, fluid pH, pressure, and temperature on bentonite’s mechanical stability was evaluated in a small- and large-scale setting. The latter was performed using realistic casing sizes and placement methods, relevant for the field application. The experimental results show that the averaged shear strength of the bentonite plug interface is 13.3 kPa and 9.1 kPa when cured in freshwater and seawater, respectively. The increase in strength with increasing curing pressure, temperature, and fluid pH was characterized for the first time. The interfacial properties of cohesion and friction angle vary with different surrounding materials. They are also influenced by the saturating condition and salinity of the saturating fluid. Based on the experimental results, a bentonite plug with a minimum length of 15–43 m placed in casings of 7–5/8″ to 13–3/8″ would be sufficient to meet the necessary criteria of the Dutch regulators as an isolating material for well abandonment.
A facile method for generating polypyrrole microcapsules and their application in electrochemical sensing
Authors: Pinyou Piyanut , Blay Vincent , Monkrathok Jirawan , Janphuang Pattanaphong , Chansaenpak Kantapat , Pansalee Jaruwan , Lisnund Sireerat
Published: October 2022

A facile and rapid strategy to generate polypyrrole microcapsules is reported. The strategy is compatible with a vortex mixer and with a microfluidic chip for droplet generation, allowing a > 100-fold reduction in particle size. The sub-micron particle sizes obtained can also be tuned to some extent based on the chip geometry. The capsules can be kept stably in solution and can be transferred onto electrochemical devices. As an application example, we casted the polypyrrole capsules generated onto screen-printed electrodes, leading to a significant increase in their electroactive surface area and capacitance. The electrodes were further modified with glucose dehydrogenase (GDH) to fabricate glucose biosensors. The introduction of polypyrrole microcapsules increased the dynamic range of the glucose sensor to ca. 300% compared with that of the electrode without polypyrrole microcapsules. The resulting glucose sensor is operated at a constant applied potential of 0.20 V vs. Ag/AgCl (3 M KCl) in an air-equilibrated electrolyte. At this potential, the sensor showed a linear range from 1.0 to 9.0 mM glucose with a sensitivity of 3.23 µA cm−2 mM−1(R2 = 0.993). The limit of detection obtained was 0.09 mM, and the reproducibility was 3.6%. The method allows generating polypyrrole microcapsules without surfactants or organic solvents and may enable new opportunities in the design of biosensors, electronic devices, and molecular delivery.

Graphical abstract