bluuebunny/crossref_metadata_2025 huggingface dataset:
Zinc oxide–silver/water hybrid nanofluid flow toward an off‐centered rotating disk using temperature‐dependent experimental‐based thermal conductivity
Authors: Mousavi Seyed Mahdi , Yousefi Mohammad , Rostami Mohammadreza Nademi , Tamim Hossein , Alimohammadian Mehdi , Dinarvand Saeed
Published: March 2022

Herein, the off‐centered stagnation flow and heat transfer of zinc oxide–silver/water hybrid nanofluid over a rotating disk according to the mass‐based algorithm is studied. It is assumed that the nanoparticles have a spherical shape. Also, the velocity slip between the base fluid and nanoparticles is negligible. The Prandtl number is kept constant at 6.2. In addition, it has been used an experimental relation for effective thermal conductivity which is a function of volume fraction and temperature. The governing partial differential equations are converted to dimensionless ordinary differential equation (ODE)s by the similarity transformation method. The simplified ODEs are solved numerically by the bvp4c function from MATLAB which is an efficient and reliable code according to the three‐stage Lobatto IIIa formula. The influence of rotational parameters and both nanoparticles masses on the profiles and quantities of engineering interest are presented and discussed in detail. It is shown that the flow becomes complicated when there is a distance between the flow axis and the disk axis. Under determined conditions for a hybrid nanofluid with 30‐g mass for both nanoparticles and 100‐g mass for pure water, adding 30 g of the second nanoparticle's mass into the base fluid leads to enhance all hydrodynamic quantities of engineering interest by about 4.3%, while dispersing 30 g of the first nanoparticle's mass inside water results in decreasing the similarity temperature gradient at the surface about 3.6%. Also, when the disk rotates faster, the maximum radial velocity near the disk, s′(0) and f″(0) increases.
Multicriteria analysis on rock moisture and streamflow in a rainfall‐runoff model improves accuracy of model results
Authors: La Follette Peter T. , Hahm W. Jesse , Rempe Daniella M. , Dietrich William E. , Brauer Claudia C. , Weerts Albrecht H. , Dralle David N.
Published: March 2022

Although shallow (1.5 m) soil water storage has been extensively studied, the significance of deeper unsaturated zone water storage to flow generation is poorly documented. However, a limited but growing body of empirical work shows that the weathered bedrock vadose zone, not soil, stores the majority of plant available water in many seasonally dry and semi‐arid landscapes. Moreover, this storage dynamic mediates recharge to hillslope groundwater systems that generate stream discharge and support ecologically significant baseflows. Explicit representations of bedrock vadose zone processes are rarely incorporated into runoff models, due in part to a paucity of observations that can constrain simulations. Here, we develop a simple representation of the weathered bedrock vadose zone that is guided by in situ field observations. We incorporate this representation into a rainfall‐runoff model, and calibrate it on streamflow alone, on rock moisture (i.e., weathered bedrock vadose zone moisture) alone, and on both using the concept of Pareto optimality. We find that the model is capable of accurately simultaneously simulating dynamics in rock moisture and streamflow, in terms of Kling‐Gupta Efficiency, when using Pareto optimal parameter sets. Calibration on streamflow alone, however, is insufficient to accurately simulate rock moisture dynamics. We further find that the posterior distributions of some model parameters are sensitive to choice of calibration scenario. The posterior distribution of high‐performing model parameters resulting from the streamflow only calibration scenario include physically unrealistic values that are not yielded by the rock moisture only or Pareto calibration strategies. These results suggest that the accuracy of some model results can be increased and parameter uncertainty decreased via incorporation of rock moisture data in calibration, without sacrificing streamflow simulation quality. Emerging recognition of the global significance of weathered bedrock water storage in seasonally dry and semi‐arid regions motivates more observations of weathered bedrock moisture and integration of this variable into earth system models.
Dietary licorice enhances in vivo cadmium detoxification and modulates gut microbial metabolism in mice
Authors: Zheng Xin , Wang Likun , You Linhao , Liu Yong‐Xin , Cohen Michael , Tian Siyu , Li Wenjun , Li Xiaofang
Published: March 2022

Mass cadmium (Cd) poisoning is a serious health problem in many parts of the world. We propose that dietary intervention can be a practical solution to this problem. This study aimed to identify effective dietary products from traditional Chinese herbs that can detoxify Cd. Five candidate herbal foods with detoxifying potential were selected and subjected to mouse toxicological tests. The chemical composition and dose–response effects of licorice on mouse hepatocytes were determined. Licorice was selected for further tests to examine its effects on growth, tissue Cd accumulation, and gut and liver fitness of mice. The expression of hepatic metallothionein (Mt) genes was quantified in vitro in hepatocytes and in vivo in liver tissues of mice. The results showed that licorice dietary intervention was effective in reducing blood Cd by >50% within 1 month. Cd was also substantially reduced in the heart and lung tissues, but increased 2.1‐fold in the liver. The liver of Cd poisoned mice improved with licorice intervention. Licorice treatment significantly induced Cd accumulation and expression of the Mt1 gene in hepatic cells both in vitro and in vivo. Licorice intake substantially altered gut microbial structure and enriched Parabacteroides distasonis. Omics results showed that licorice improved gut metabolism, particularly the metabolic pathways for glycyrrhizin, bile acids, and amino acids. Dietary licorice effectively reduced mouse blood Cd and had a profound impact on liver and gut fitness. We conclude that herbal licorice can be used as a dietary intervention for mass Cd poisoning.
Fetal brain imaging: A comparison between fetal ultrasonography and intra uterine magnetic resonance imaging (a systematic review and meta‐analysis)
Authors: Moradi Behnaz , Parooie Fateme , Kazemi Mohammad Ali , Hashemi Hassan , Miratashi Yazdi Seyedeh Nooshin
Published: March 2022

Objective

The aim of this study was to compare ultrasound (US) and intra uterine MRI (IUMRI) of the brain in the diagnosis of fetal brain abnormalities.

Methods

The present systematic review is done based on guidelines for preferred reporting items for systematic reviews and meta‐analysis. All major articles comparing fetal US with IUMRI in fetuses with suspected brain abnormalities were qualified. Articles published before 2010 were excluded from the study. An I2 > 20% was considered as a sign of significant change. The statistical analysis was done using STATA −15 and Meta‐Disk 1.4 applications.

Results

Five articles were considered for meta‐analysis. The sensitivity of US and IUMRI in diagnosing fetal abnormalities were 86% and 95%, respectively. The corresponding rates for specificity were 77% and 80%. IUMRI and US were concordant in 72.5% (95% CI: 68%–77%) of diagnoses. However, IUMRI added information in 21.7% of cases, while US added value was only 1.48.

Conclusion

Our results approved the good diagnostic performance of both US and IUMRI in confirming fetal brain normal development and emphasized that US is an appropriate screening technique in pregnancy. In cases of detected abnormalities in US, IUMRI is suggested as it was the most accurate imaging method and added information about the diagnosis in 22.2% of cases.
Variation in the prevalence of cough symptoms 4–5 days after infection with SARS‐CoV‐2 between seasons with different prevalent strains
Authors: Akaishi Tetsuya , Ishii Tadashi
Published: March 2022

Background

The coronavirus disease 2019 (COVID‐19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) remains a major global health concern in 2022. The association between the rapid spread of the variants, which eliminated the original strain, and clinical manifestations with the variants remains undetermined.

Methods

This was a population‐based longitudinal cohort study. Whole citizens in a city with approximately one million population who had contacted COVID‐19 patients and were tested by nasopharyngeal SARS‐CoV‐2 reverse transcription‐polymerase chain reaction (RT‐PCR) swab test between July 2020 and March 2021 were enrolled. Detailed contact episode and the presence of cough symptoms 4–5 days after contact with patients having COVID‐19 were evaluated.

Results

Among the 359 RT‐PCR test‐positive patients, 88 (24.5%) developed cough symptoms by 4–5 days from the infection. The same rate in RT‐PCR test‐negative cases was 8.6%. The prevalence of cough did not significantly differ by age, sex, and places or closeness of the contact episode. The rate of cough symptoms in RT‐PCR test‐positive patients increased in February–March 2021 with E484K variant predominance compared to that in July–December 2020 with the original strain (32.9% vs 19.4%, p = 0.0221), whereas the cough prevalence among RT‐PCR test‐negative population did not increase. Cough symptoms in COVID‐19 patients was associated with strong fatigability, but was independent from fever or dysosmia.

Conclusions

Cough symptoms 4–5 days after infection with SARS‐CoV‐2 was suggested to have increased with E484K variant, compared to the original strain.
Metabolic disease in the Pacific: Lessons for indigenous populations
Authors: Wilson Callum
Published: March 2022

Twenty‐five percent of the New Zealand population is either Māori or Pacific and are thus indigenous to the region. The New Zealand National Metabolic Service has considerable experience in diagnosing and managing metabolic diseases in this population. The frequencies and phenotypes of inborn errors of metabolism in indigenous people differ from that in Western European populations. Metabolic services need to be aware of these local variations and adapt their screening and treatment protocols accordingly. Likewise, the services themselves need to adopt culturally appropriate practices. This includes an understanding of the language, ideally employment of indigenous people and targeting of the service to meet the needs of the people. Knowledge of the metabolic diseases common within particular ethnic groups is important for the rapid delivery of appropriate management. Newborn screening protocols need to reflect the local populations. With the advent of expanded newborn screening relatively benign forms of fatty acid oxidation disorders have been commonly encountered. This high prevalence may reflect a selective evolutionary advantage as similar conditions have been found in other ethnic groups with traditionally high fat and low carbohydrate diets. HLA haplotypes of indigenous populations are less represented in international stem cell transplant databanks thereby making the option of human stem cell transplant more challenging. The recent discovery that short‐chain enoyl‐CoA hydratase deficiency is particularly common in New Zealand with nearly a dozen cases identified this year suggests there is still a lot to learn regarding Māori and Pacific and indeed an indigenous metabolic disease.
Remote video interface psychological assessment during the COVID‐19 pandemic: Experiences of consultants and clients
Authors: Martínez‐Cengotitabengoa Maria‐Teresa , Sanchez‐Martinez Andoni , Long‐Martinez Daniel , Sanchez‐Martínez Monike , Peters‐Corbett Araminta , Pugh Eleanor J. , Field Fraser W. F. , Martínez‐Cengotitabengoa Mónica
Published: March 2022

The need for remote psychological assessment came to the fore during the Covid‐19 pandemic lockdown. This paper examines the qualitative experiences of psychologists and patients using remote video interfaces for psychological assessment during that period. The aim was to gain qualitative data on the personal experiences of both parties and explore whether remote assessment via video interface is a satisfactory method for psychological evaluations. Patients were seen for psychological assessments by consultant Clinical and Counselling Psychologists via through videoconference. Consultants and patients were asked about their experience of the video assessment and the consultant recorded their responses. Content Analysis was used to analyse the responses. The remote mode of assessment was found to be satisfactory to both patient and psychologist, although technical issues were highlighted to be the most disruptive to assessments. Consultants reported a certain level of fatigue, particularly after evaluations, and some of them commented that they had to try harder than in a face‐to‐face evaluation. Distraction in the patient environment was considered detrimental. The small sample size which requires further replication studies. Overall, the use of videoconference was found to be a satisfactory method for psychological assessment with some areas for improvement, such as technical difficulties and fatigue.
Structures, functions, and inhibitors of LUBAC and its related diseases
Authors: Ning Shuo , Luo Lingling , Yu Beiming , Mai Dina , Wang Feng
Published: March 2022

Ubiquitination is a reversible posttranslational modification in which ubiquitin is covalently attached to substrates at catalysis by E1, E2, and E3 enzymes. As the only E3 ligase for assembling linear ubiquitin chains in animals, the LUBAC complex exerts an essential role in the wide variety of cellular activities. Recent advances in the LUBAC complex, including structure, physiology, and correlation with malignant diseases, have enabled the discovery of potent inhibitors to treat immune-related diseases and cancer brought by LUBAC complex dysfunction. In this review, we summarize the current progress on the structures, physiologic functions, inhibitors of LUBAC, and its potential role in immune diseases, tumors, and other diseases, providing the theoretical basis for therapy of related diseases targeting the LUBAC complex.
Third order inverse multifunction filter employing MOS resistors and capacitors
Authors: Banerjee Subhasish , Ghosh Mourina , Mondal Pulak , Ranjan Ashish
Published: March 2022

This paper presents a systematic approach for the realization of multifunction filter that includes third order inverse low pass filter (ILPF), band pass filter (IBPF), and high pass filter (IHPF) using two Operational Transresistance Amplifiers (OTRAs), MOS resistors, and few number of capacitors. An operational activity of inverse filter configuration (IFC) can be easily realized by proper selection of switches. In ideal case, third order of the filter characterizes a total roll‐off of 60 dB/decade but the proposed design offers a roll‐off in the range of 48.09 dB/decade to 57.74 dB/decade which may arises due to passive component tolerance and some design parameters. The proposed design brings an improvement in roll‐off around 20%–44% in comparison to existing literatures. The multifunction filter frequency response (ILPF, IBPF, and IHPF) is observed by using PSPICE simulation in which the core of the filter “OTRA” is integrated with 180 nm Taiwan Semiconductor Manufacturing Company (TSMC) CMOS technology parameter. In addition to simulation results, hardware implementation of the proposed filter configuration validates the theoretical aspect of filter design.
Temporal variation of saturated and near‐saturated soil hydraulic conductivity and water‐conducting macroporosity in a maize‐wheat rotation under conventional and conservation tillage practices
Authors: Singh Deepak , Patra Sridhar , Mishra Alok Kumar , Mariappan Sankar , Singh Nisha
Published: March 2022

Knowledge of temporal variation of soil hydraulic properties (SHPs) is crucial to understand soil physical behaviour under different tillage practices. The objective of this study was to assess the variation of saturated and near‐saturated soil hydraulic conductivity (NSHC) and water‐conducting macroporosity (Ɛ) under long‐term (09 years) tillage regimes viz. zero tillage (ZT), conventional tillage (CT), and minimum tillage (MT) in a rain‐fed maize‐wheat crop rotation (RMWC) in the North‐West Himalayas, India (NWHI). A hood infiltrometer (HI) was used to measure the steady‐state water flux (q) at 0, −10, and −30 mm pressure head (PH) after harvesting of maize and over two wheat cropping seasons for each treatment. The infiltration data were analyzed in terms of unsaturated hydraulic conductivity k(h), field saturated hydraulic conductivity (ks), water‐conducting macroporosity (Ɛ). The results showed that the seasonal effects on ks, k(h), and Ɛ values were significantly different (p ≤0.05) for tilled treatments (CT and MT). In contrast, no significant difference (p ≤0.05) was found for untilled treatment (ZT). Significantly higher (p ≤0.05) ks, k(h), and Ɛ values were observed in ZT than CT and MT, associated with higher SOC and lower ρb values. A multivariate analysis of variance of the ks showed a highly significant difference (p ≤0.01) with both time and tillage treatments. Overall, a significant improvement of hydraulic conductivity characteristics was observed during the wheat‐growing seasons compared with the maize harvest season. The temporal dynamics of SHPs under different tillage regimes indicate that ZT can be a suitable tillage practice for reducing runoff and soil loss in monsoon maize and winter wheat cropping system.
Soil organic carbon stock assessment in forest ecosystems through pedogenic horizons and fixed depth layers sampling: What's the best one?
Authors: De Feudis Mauro , Falsone Gloria , Vianello Gilmo , Agnelli Aberto , Vittori Antisari Livia
Published: March 2022

In soil organic carbon (SOC) survey, the role of sampling approach is crucial and should not be underestimated. In this sense, the appropriateness of soil sampling by pedogenic horizons (PGH) and fixed depth layers (FDL) in forest is still a field of debate. The present work aimed to: (a) study the spatial variability of SOC concentrations and C stocks through PGH and FDL samplings in uneven‐aged sweet chestnut, European beech and Norway spruce forests of the Apennine chain (Italy); (b) clarify the major advantages and drawbacks of sampling by PGH and FDL. In a representative area (18 × 18 m) of each forest, a soil profile was investigated and eight additional sampling points were selected. The sampling was performed both by PGH and FDL (0–15 and 15–30 cm). For each forest, no SOC content and C stock differences in 0–30 cm soil depth were found between PGH (58.8 ± 5.3 g kg−1 and 103 ± 7 g ha−1, respectively) and FDL (52.7 ± 4.3 g kg−1 and 117 ± 9 Mg ha−1, respectively) sampling. However, under Norway spruce, PGH sampling pointed‐out that C was mainly stored in Oe and Oa horizons (51.1 vs. 146 Mg ha−1 in the 0–30 cm layer). The higher coefficient of variation obtained when soil horizons were considered (from 19.2% to 72.8% for PGH and from 16.5% to 25.7% for FDL) suggested that PGH sampling preserved the information about the spatial variability within an ecosystem. The information loss about SOC vertical and spatial distribution would indicate the inability of FDL sampling to support decision‐making plans addressed for sustainable use of soil resource.
Effects of Regioregularity of π‐Conjugated Polymers Composed of Boron β‐Diketiminate on Their Stimuli‐Responsive Luminescence
Authors: Ito Shunichiro , Fukuyama Misuzu , Tanaka Kazuo , Chujo Yoshiki
Published: March 2022

π‐Conjugated polymers composed of a boron β‐diketiminate complex with different regioregularity are synthesized by using Suzuki–Miyaura and Yamamoto couplings. The films formed with the polymers show luminescence chromism upon exposure to solvent vapors. Most importantly, the chromic behavior depends on the regioregularity of the polymers. Wide‐angle X‐ray diffraction, thermal analysis, and density functional theory calculations suggest that the chromism can originate from the morphological change in the films and the alternation of the electronic nature of the main chains.
Seamless All‐Solid‐State Supercapacitor Fabricated Using a Proton‐Conducting Methanesulfonic Acid‐Intercalated Graphene Oxide Film as an Electrolyte
Authors: Ohori Kei , Hatakeyama Kazuto , Koinuma Michio , Ida Shintaro
Published: March 2022

An all‐solid‐state supercapacitor with no boundary between the electrode/electrolyte interface is prepared using methanesulfonic acid (MSA)‐intercalated graphene oxide (GO)　membranes as a proton‐conducting electrolyte. The electrodes (reduced GO) are formed within the surface of the solid GO electrolyte by a combination of self‐reduction of the GO under UV‐light illumination and electrochemical reduction. In this process, the surface of the GO film is converted to an electrode material with mixed electron/proton conduction, which results in the formation of a seamless capacitor structure. The resultant capacitor shows a large capacitance of 33.8 mF cm−2, 11.9 F g–1 (g: total weight of device including electrodes, electrolyte, separator and current collector), which is 15 times higher than the capacitance retention of an all‐solid‐state supercapacitor fabricated using proton‐conducting GO film. The seamless structures for the electrode/electrolyte interface suppress the decomposition of the GO electrolyte by the local concentration of applied voltage, resulting in improved cycle stability. The very large capacitance is likely derived not only from the seamless structure but also from the high proton conductivity of the MSA‐intercalated GO electrolyte (4.2 × 10−3 S cm−1).
Feature fusion Siamese network for breast cancer detection comparing current and prior mammograms
Authors: Bai Jun , Jin Annie , Wang Tianyu , Yang Clifford , Nabavi Sheida
Published: March 2022

Purpose

Automatic detection of very small and nonmass abnormalities from mammogram images has remained challenging. In clinical practice for each patient, radiologists commonly not only screen the mammogram images obtained during the examination, but also compare them with previous mammogram images to make a clinical decision. To design an artificial intelligence (AI) system to mimic radiologists for better cancer detection, in this work we proposed an end‐to‐end enhanced Siamese convolutional neural network to detect breast cancer using previous year and current year mammogram images.

Methods

The proposed Siamese‐based network uses high‐resolution mammogram images and fuses features of pairs of previous year and current year mammogram images to predict cancer probabilities. The proposed approach is developed based on the concept of one‐shot learning that learns the abnormal differences between current and prior images instead of abnormal objects, and as a result can perform better with small sample size data sets. We developed two variants of the proposed network. In the first model, to fuse the features of current and previous images, we designed an enhanced distance learning network that considers not only the overall distance, but also the pixel‐wise distances between the features. In the other model, we concatenated the features of current and previous images to fuse them.

Results

We compared the performance of the proposed models with those of some baseline models that use current images only (ResNet and VGG) and also use current and prior images (long short‐term memory [LSTM] and vanilla Siamese) in terms of accuracy, sensitivity, precision, F1 score, and area under the curve (AUC). Results show that the proposed models outperform the baseline models and the proposed model with the distance learning network performs the best (accuracy: 0.92, sensitivity: 0.93, precision: 0.91, specificity: 0.91, F1: 0.92 and AUC: 0.95).

Conclusions

Integrating prior mammogram images improves automatic cancer classification, specially for very small and nonmass abnormalities. For classification models that integrate current and prior mammogram images, using an enhanced and effective distance learning network can advance the performance of the models.
Supramolecular p/n‐heterojunction of C60‐functionalized bis(merocyanine) quadruple stack: A model system for charge carrier separation and recombination in organic solar cells
Authors: Bialas David , Fennel Franziska , Noll Niklas , Holzapfel Marco , Schmiedel Alexander , Lambert Christoph , Würthner Frank
Published: March 2022

Supramolecular photosystems can afford important insights into elementary processes in molecular materials. Here, a bis(merocyanine)‐C60 conjugate composed of two covalently tethered electron‐donating merocyanine chromophores and two appended fullerene electron acceptor units is investigated. Concentration‐dependent UV/Vis studies in nonpolar solvents revealed a bimolecular association (dimerization) process, resulting in the formation of an H‐coupled merocyanine dye aggregate. The aggregate structure was confirmed by 2D NMR spectroscopy proving the presence of a well‐defined quadruple dye stack surrounded by four loosely connected fullerenes, which mimics the donor–acceptor interface in bulk heterojunction (BHJ) solar cells. Due to the interdigitation of the dyes in the quadruple stack motif, even at low concentrations, fully aggregated species prevail in nonpolar solvents, which enabled us to elucidate the photophysics of this supramolecular p/n‐heterojunction in dilute solution by femtosecond time‐resolved transient absorption spectroscopy. The observed photophysical processes include a favorably fast photoinduced electron transfer from the electron‐donating dye stack to the electron‐accepting fullerene moieties, a slower geminate charge carrier recombination of the generated electron and hole in the supramolecular p/n‐heterojunction as well as the formation of fullerene triplet states. While the geminate recombination of charge carriers is supposed to be less competitive in BHJ photovoltaic materials due to the possibility of fast electron migration within fullerene domains in thin films, intersystem crossing into the triplet manifold appears as a more critical undesired process. These insights from spectroscopy may help to tailor improved photovoltaic materials, thereby demonstrating the value of fundamental studies on elementary photophysical processes in molecular aggregates.

KEY POINTS

Supramolecular p/n‐heterojunction by self‐assembly in solution

Aggregate structure confirmed by NMR spectroscopy

Photoinduced electron transfer studied by transient absorption spectroscopy
A new ϕ‐FEM approach for problems with natural boundary conditions
Authors: Duprez Michel , Lleras Vanessa , Lozinski Alexei
Published: March 2022

We present a new finite element method, called ‐FEM, to solve numerically elliptic partial differential equations with natural (Neumann or Robin) boundary conditions using simple computational grids, not fitted to the boundary of the physical domain. The boundary data are taken into account using a level‐set function, which is a popular tool to deal with complicated or evolving domains. Our approach belongs to the family of fictitious domain methods (or immersed boundary methods) and is close to recent methods of CutFEM/XFEM type. Contrary to the latter, ‐FEM does not need any nonstandard numerical integration on cut mesh elements or on the actual boundary, while assuring the optimal convergence orders with finite elements of any degree and providing reasonably well conditioned discrete problems. In the first version of ‐FEM, only essential (Dirichlet) boundary conditions was considered. Here, to deal with natural boundary conditions, we introduce the gradient of the primary solution as an auxiliary variable. This is done only on the mesh cells cut by the boundary, so that the size of the numerical system is only slightly increased. We prove theoretically the optimal convergence of our scheme and a bound on the discrete problem conditioning, independent of the mesh cuts. The numerical experiments confirm these results.
Effect of Protrusion on Combustion Stability of Hybrid Rocket Motor
Authors: Dinesh Mengu , Kumar Rajiv
Published: March 2022

In hybrid rockets, low regression rate and low combustion efficiency are major drawbacks restricting its utilization in practical applications. Inserting a protrusion in a hybrid rocket combustion chamber is one of the methods to enhance the regression rate and combustion efficiency. In the present study, while utilizing the protrusion method the combustion stability of the hybrid rocket was investigated. The protrusions used for this study were of two different types; one was made of graphite and another one was nylon. The nylon protrusion can regress during the combustion along with the fuel whereas, graphite cannot. Before using the protrusion method, the combustion stability of the hybrid rocket motor (base case) was characterized. During the combustion of the base case motor, intense pressure oscillations were observed for a definite period after the beginning of the combustion. These oscillations were found to be the result of the interaction between the vortex shedding and fundamental longitudinal acoustic modes of the chamber at the fuel grain exit. Upon inserting the protrusion near the fuel grain exit, significant suppression in the pressure oscillations was observed. A 96 % reduction in amplitude of acoustic modes relative to the base case was observed. There was no substantial difference in combustion stability of the hybrid rocket when using graphite or nylon protrusions. Further, it was realized that the combustion stability of the rocket motor remains unchanged even after varying the thickness of the protrusion at 0.8X/L location.
Insertion of an Ultrathin Interfacial Aluminum Layer for the Realization of a Hf0.5Zr0.5O2 Ferroelectric Tunnel Junction
Authors: Manchon Benoît , Segantini Greta , Baboux Nicolas , Rojo Romeo Pedro , Barhoumi Rabei , Infante Ingrid C. , Alibart Fabien , Drouin Dominique , Vilquin Bertrand , Deleruyelle Damien
Published: March 2022

Herein, the effect of a 2 nm thin aluminum layer inserted between the ferroelectric layer and the top electrode in a TiN//TiN stack deposited by reactive magnetron sputtering is investigated. The oxidation of the interfacial layer during annealing due to scavenging of the impacts both the ferroelectric properties and the electrical conductivity of the junction. It is shown that the overall conductivity of the junction is boosted 20 folds while the resistance ratio between the positive and negative polarization states is increased from 1.3 up to 3.7. Through a systematic analysis of programming conditions, pulse duration, and height, we show that both the remanent polarization and On/Off current ratio can be enhanced at the expanse of the endurance leading to a trade‐off.
Detection of glutathione, cysteine, and homocysteine by online derivatization‐based electrospray mass spectrometry
Authors: Yin Yiyan , Zhen Boyu , Sun Jianghui , Ouyang Jin , Na Na
Published: March 2022

Rationale

Electrospray ionization mass spectrometry (ESI‐MS) is one of the most popular techniques for obtaining structural information, which is commonly used in bioanalysis and clinical diagnostics. However, for the detection of complicated samples with high reactivities (such as reactive sulfur species, RSS), traditional ESI‐MS usually suffers from overlapped and inaccurate signals. In this study, based on the multiphase flow of extractive electrospray ionization (MF‐EESI), an ambient MS technique of online derivatization was proposed to detect thiols without any other sample pretreatment.

Methods

RSS molecules and the derivatization reagent of 4‐chloro‐7‐nitro‐1,2,3‐benzoxadiazole (NBD‐Cl) were introduced into the internal and innermost capillary of the MF‐EESI system, respectively. By a high‐velocity nebulizing stream of N2 gas through an external capillary, both flows of innermost biothiols and internal NBD‐Cl were electrosprayed and mixed for online reactions. Therefore, the fast derivatization of thiols was used to generate stable ionized derivatives for MS detection.

Results

By evaluating the changes in MS signals before and after the derivatization, the ions of RSS were identified simply and correctly. Without any sample pretreatment, the fast detection of cysteine, homocysteine, and glutathione has been achieved in the complicated samples.

Conclusions

The present online derivatization‐based MF‐EESI was successfully used for fast, simple, and accurate detection of biothiols. This presented a potential pathway for the fast identification of thiols in complicated samples.
A case of pulmonary thromboembolism possibly associated with the use of creatine supplements
Authors: Lee So Hyun , Seo Jin A , Park Ji Eun , Kim Chang Ho , Lee Jaehee
Published: March 2022

Drug administration should be considered a risk factor for venous thromboembolism (VTE) in younger healthy patients. We present a case of new‐onset pulmonary embolism (PE), possibly associated with excessive creatine supplement intake. A 24‐year‐old non‐smoker male presented to the emergency department with sudden‐onset dyspnoea and chest discomfort. Computed tomography pulmonary angiography and venography confirmed PE in the left and right pulmonary artery branches and a thrombus in the left popliteal vein. The patient had no family history of VTE, and other causes of thrombophilia were unlikely. He reported a recent increase in the intensity of his workouts and the dose of his creatine supplements in preparation for a bodybuilding competition. The creatine supplements likely promoted dehydration during intense workouts and profuse sweating. He received anticoagulation therapy, and the creatine supplements were discontinued. Creatine supplements should be used cautiously when there is a higher risk of becoming dehydrated.
Accumulation of fibrosis and altered perifollicular stromal differentiation in vitrified‐thawed human ovarian tissue xenografted to nude mice.
Authors: Kitajima Michio , Murakami Naoko , Kitajima Yuriko , Kajimura Itsuki , Matsumura Asako , Matsumoto Kanako , Harada Ayumi , Miura Kiyonori
Published: March 2022

Purpose

Ovarian tissue cryopreservation and its auto‐transplantation is promising technique in fertility preservation. Longevity of grafted tissue is limited though mechanism of follicle reduction is not fully understood. We evaluated histological alteration of vitrified‐thawed ovarian tissue that grafted to nude mice.

Materials and Methods

Human ovarian tissue was cryopreserved by vitrification. After thawing, they were grafted to mesentery of nude mice. Twelve weeks after transplantation, the implants were removed and histologically examined. The presence of follicles, the degree of fibrosis, and TUNEL staining in surrounding cortex were evaluated. The stromal expressions of alpha‐smooth muscle actin (aSMA) were determined.

Results

Normal ovarian cortex was decreased, and fibrotic area were significantly increased after grafting. The distributions of developmental stage of follicles shifted toward activation of follicular growth. Stromal TUNEL staining was increased in frozen/thawed tissue. The expression of aSMA were found in perifollicular stroma of growing follicles, which were decreased in grafted tissue associated with reduction of cortical stroma.

Conclusions

Fibrosis, reduced cortical stroma, and activation of dormant follicles were concomitantly observed in grafted ovarian cortex, which may relate to limited longevity. Perifollicular aSMA expression can be regarded as a marker of the competence of cortical stroma that regulate follicular development.
Revealing the revealed preferences of public firm CEOs and top executives: A new database from credit card spending
Authors: Raffiee Joseph , Fehder Daniel , Teodoridis Florenta
Published: March 2022

Research Summary

We introduce a new database which provides an unprecedented window into the off‐the‐job lives and interests of public firm top executives as reflected by their personal income allocation. We construct this database by matching household credit card spending data with the population of executives in Execucomp. To overcome the significant computational challenges associated with matching these data, we build on the statistical record‐linking literature in a way that allows us to generate reliable matches with limited information. To facilitate research exploring new questions made possible with this database, we make our matching crosswalk freely available for academic use.

Managerial Summary

This article describes the matching procedures associated with the development of a database which sheds new light on the revealed preferences of public firm top executives. Prior work on upper echelons has routinely stressed how preferences and characteristics of top executives often manifest in firm behaviors and are important predictors of firm outcomes. Nevertheless, the lack of a reliable paper trail capturing executive preferences, particularly at a large scale, has been a friction slowing comprehensive empirical research on this topic. We describe how we address this limitation by linking top executives listed in the database Execucomp with credit card spending data provided by the consumer data provider L2 and outline a number of new research questions made possible by our matching efforts. The results of our matching efforts (Execucomp‐L2 unique identifier crosswalk) are available at https://github.com/dfehder/FRT_2022_SMJ_CEO_TopExec_Preferences.
Synthesis and Catalytic Property of Ribonucleoside‐Derived Carbon Dots
Authors: Li Shuai , Li Feng , Dong Yuhang , Song Nachuan , Pan Li , Yang Dayong
Published: March 2022

Exploring appropriate precursors has been proposed to be a promising strategy for the creation of artificial enzymes that are emerging as alternatives of natural enzymes. Herein, inspired by the catalytic activities of ribose nucleic acid, using ribonucleosides as precursors including adenosine, guanosine, cytidine, and uridine, respectively, four carbonic aggregates, namely, carbon dots (A‐CDs, G‐CDs, C‐CDs, and U‐CDs) to mimic artificial enzymes are synthesized. All the CDs show a planar graphene‐like structure and thus can intercalatively bind with DNA double helix. Different from the other three CDs, the uridine‐derived U‐CDs exhibit unique catalytic property, which can mediate the topological transformation of DNA from supercoiled to nicked open‐circular conformation. U‐CDs can catalyze oxidation of O2 to generate singlet oxygen 1O2 via a Haber–Weiss reaction, and consequently mediate oxidative cleavage of phosphate backbone in DNA and release the torsional energy stored in supercoiled DNA. Explorations reveal that the unique highly active oxygenated species, namely, quinone groups that are on the edge of U‐CDs, play a key role in the catalytic production of 1O2. This work represents a new insight that using natural biomolecules in living systems as precursors can create new species beyond life.
Engineering Hierarchical Architecture of Metal‐Organic Frameworks for Highly Efficient Overall CO2 Photoreduction
Authors: Huang Hai‐Bo , Fang Zhi‐Bin , Wang Rui , Li Lan , Khanpour Mojtaba , Liu Tian‐Fu , Cao Rong
Published: March 2022

Previous studies on syntheses of metal‐organic frameworks (MOFs) for photocatalytic CO2 reduction are mainly focused on the exquisite control over the net topology and the functionality of metal clusters/organic building blocks. This contribution demonstrates that the rational design of MOF‐based photocatalyst can be further extended to the hierarchical structure at micrometer scales well beyond the conventional MOF design at the molecular level. By taking advantage of the disparity of two selective MOFs in nucleation kinetics, a hierarchical core–shell MOF@MOF structure is successfully constructed through a simple one‐pot synthesis. Besides inheriting the high porosity, crystallinity, and robustness of parent MOFs, the obtained heterojunction exhibits extended photoresponse, optimized band alignment with large overpotential, and greatly enhanced photogenerated charge separation, which would be hardly realized by the merely molecular‐level assembly. As a result, the challenging overall CO2 photoreduction is achieved, which generates a record high HCOOH production (146.0 µmol/g/h) without using any sacrificial reagents. Moreover, the core–shell structure exhibits a more effective use of photogenerated electrons than the individual MOFs. This work shows that harnessing the hierarchical architecture of MOFs present a new and effective alternative to tuning the photocatalytic performance at a mesoscopic level.
Efficient Surface‐Defect Passivation by Sulfurous‐Acyl‐Included Small Molecule for High‐Performance Perovskite Photovoltaics
Authors: Chen Lin , Lou Yan-Hui , Wang Kai-Li , Öz Senol , Wang Zhao-Kui , Liao Liang-Sheng
Published: March 2022

Perovskite photovoltaics have drawn tremendous attention due to their excellent photoelectric performance and possess promising potential in the field of renewable energy. Although the photoelectric conversion efficiency of perovskite solar cells has made a quantum leap, stability is still a limitation to its long‐term development and has become the main issue that needs to be solved urgently. The defects in the perovskite films and at the grain boundaries are important factors affecting the stability of perovskite photovoltaics. It is reported that the surface defect of the perovskite film is two to four orders of magnitude higher than the bulk defect. Herein, 4‐bromobenzenesulfonyl chloride to modify the surface defects of perovskite films is introduced. Through the interaction between S = O in 4‐bromobenzenesulfonyl chloride and the bare Pb2+ in the perovskite film, the crystal quality of the perovskite film is significantly improved and the surface defects are effectively passivated. The optimized device achieves a champion power conversion efficiency of 21.84%, and the efficiency can retain 92% of the initial value after 1200 h. This finding provides a method to improve the device performance of perovskite solar cells.
Merit Evaluation of Peer‐to‐Peer Electricity Trading Between Prosumers
Authors: Odashiro Tomoya , Hara Ryoichi , Kita Hiroyuki
Published: March 2022

The enforcement of a feed‐in tariff (FIT) program in Japan has increased the number of installations of photovoltaic generation systems in its residential sector. After the end of an FIT program, the surplus electricity of an individual prosumer is purchased by the utility company at a reduced price, which may have an economic impact on the prosumer. To avoid this adverse effect, peer‐to‐peer (P2P) electricity transactions among prosumers based on blockchain and smart contract technologies as well as introduction of residence‐use stationary storage batteries are generating significant interest. In this study, the potential economic merit of P2P transactions and residential storage battery introduction are evaluated using a total optimization approach. For realizing a more practical perspective, this study also investigates the economic merit based on a partial optimization approach, in which an individual prosumer pursues its own profit. Furthermore, in this study, the grid‐side merit of P2P electricity transactions among prosumers is examined. Comparison of the merits determined by the total and partial optimization approaches shows that the realization of P2P transactions could provide a notable economic merit to the participants and reduce both the required facility capacity and power flow variation. © 2022 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.
A Cesarean scar pregnancy is not an ectopic pregnancy
Authors: Timor‐Tritsch I. E.
Published: March 2022

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Gut microbiota and inflammatory bowel disease
Authors: Chen Liang , Wang Jun
Published: March 2022

Gut microbiota refers to the complex aggregation of microbes in gut, including bacteria, archaea, fungi, and viruses, and they exert marked influence on the host's health. Perturbations in the gut microbiota have been closely linked to initiation and progression of IBD, which has become a disease with accelerating incidence worldwide, but it remains to be thoroughly investigated how microbial involvement might contribute to IBD. In this review, we discuss the current research findings concerning alterations in the gut microbiota, trans‐kingdom interaction between the members of the gut microbiota, their interactions with the immune system of host, their potential role in the IBD pathogenesis, and the relationship between gut microbiota and IBD. We hope to provide a better understanding of the causes of IBD and shed light on the development of microbiome‐based therapeutic approaches, which might be a promising strategy to alleviate, manage, and eventually cure IBD.

This article is categorized under:

Infectious Diseases > Genetics/Genomics/Epigenetics

Infectious Diseases > Molecular and Cellular Physiology
On uniqueness and stability for the Boltzmann–Enskog equation
Authors: Friesen Martin , Rüdiger Barbara , Sundar Padmanabhan
Published: March 2022

The time-evolution of a moderately dense gas in a vacuum is described in classical mechanics by a particle density function obtained from the Boltzmann–Enskog equation. Based on a McKean–Vlasov equation with jumps, the associated stochastic process was recently constructed by modified Picard iterations with the mean-field interactions, and more generally, by a system of interacting particles. By the introduction of a shifted distance that exactly compensates for the free transport term that accrues in the spatially inhomogeneous setting, we prove in this work an inequality on the Wasserstein distance for any two measure-valued solutions to the Boltzmann–Enskog equation. As a particular consequence, we find sufficient conditions for the uniqueness and continuous-dependence on initial data for solutions to the Boltzmann–Enskog equation applicable to hard and soft potentials without angular cut-off.
Prognosemodelle zur Steuerung von intensivmedizinischen COVID-19-Kapazitäten in Deutschland
Authors: Grodd Marlon , Refisch Lukas , Lorenz Fabian , Fischer Martina , Lottes Matthäus , Hackenberg Maren , Kreutz Clemens , Grabenhenrich Linus , Binder Harald , Wolkewitz Martin
Published: March 2022

Hintergrund

Zeitdynamische Prognosemodelle spielen eine zentrale Rolle zur Steuerung von intensivmedizinischen COVID-19-Kapazitäten im Pandemiegeschehen. Ein wichtiger Vorhersagewert (Prädiktor) für die zukünftige intensivmedizinische (ITS-)COVID-19-Bettenbelegungen ist die Anzahl der SARS-CoV-2-Neuinfektionen in der Bevölkerung, die wiederum stark von Schwankungen im Wochenverlauf, Meldeverzug, regionalen Unterschieden, Dunkelziffer, zeitabhängiger Ansteckungsrate, Impfungen, SARS-CoV-2-Virusvarianten sowie von nichtpharmazeutischen Eindämmungsmaßnahmen abhängt. Darüber hinaus wird die aktuelle und auch zukünftige COVID-ITS-Belegung maßgeblich von den intensivmedizinischen Entlassungs- und Sterberaten beeinflusst.

Methode

Sowohl die Anzahl der SARS-CoV-2-Neuinfektionen in der Bevölkerung als auch die intensivmedizinischen COVID-19-Bettenbelegungen werden bundesweit flächendeckend erfasst. Diese Daten werden tagesaktuell mit epidemischen SEIR-Modellen aus gewöhnlichen Differenzialgleichungen und multiplen Regressionsmodellen statistisch analysiert.

Ergebnisse

Die Prognoseergebnisse der unmittelbaren Entwicklung (20-Tage-Vorhersage) der ITS-Belegung durch COVID-19-Patienten*innen werden Entscheidungsträgern auf verschiedenen überregionalen Ebenen zur Verfügung gestellt.

Schlussfolgerung

Die Prognosen werden der Entwicklung von betreibbaren intensivmedizinischen Bettenkapazitäten gegenübergestellt, um frühzeitig Kapazitätsengpässe zu erkennen und kurzfristig reaktive Handlungssteuerungen, wie etwa überregionale Verlegungen, zu ermöglichen.