bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification and characterization of the chemical components of Iris tectorum Maxim. and evaluation of their nitric oxide inhibitory activity
Authors: Gao Bo , Ma Yu , Zhang Li‐tao , Ren Qiang
Published: October 2020

Rationale

Iris tectorum Maxim. is a traditional medicinal herb that is commonly used to treat inflammatory conditions. The present study investigated the fragmentation patterns of isoflavone glycosides and their qualitative analysis. In addition, lipopolysaccharide (LPS)‐induced RAW264.7 macrophages were used to evaluate the anti‐inflammatory properties of I. tectorum Maxim. samples collected at different time points during the year.

Methods

High‐performance liquid chromatography/quadrupole time‐of‐flight tandem mass spectrometry (HPLC/QTOF‐MS/MS) and HPLC with diode‐array detection were employed for qualitative and quantitative analysis. The fragmentation patterns of the isoflavones were observed in negative electrospray ionization mode with collision‐induced dissociation (CID). Their anti‐inflammatory activity was assessed via nitric oxide (NO) production in LPS‐treated RAW264.7 macrophages.

Results

A total of 15 chemical components were observed and tentatively identified using HPLC/QTOF‐MS/MS. At low collision energy, the relative abundances of the aglycone radical anions Y0−, [Y0 − H]−•, [Y0 − CH3]−• and [Y0 − H− CH2]−• were used for the structural characterization of tectoridin and tectorigenin‐4′‐O‐β‐D‐glucoside. The radical ions [Y0 − CH3]−• and [Y0 − H − 2CH3]−• were also employed to differentiate between iristectorin A and iristectorin B based upon their high‐energy CID spectra. Levels of 9.02 mg/g of tectoridin and 1.04 mg/g of tectorigenin were found in samples collected in June, which exhibited 69.7% NO inhibitory activity.

Conclusions

The characteristic fragmentation patterns enabled us to reliably identify isoflavone glycosides. The results of the quantitative determination and NO inhibitory activity offer insight into the optimal I. tectorum Maxim. harvesting time.
The CMS Emergency Preparedness Rule: Challenges for Rural Medical Centers
Authors: Sloan Leslie C. , Obisesan Olawunmi
Published: October 2020

This study examines how rural medical centers in Northwest Missouri achieve emergency planning compliance with the current Centers for Medicare and Medicaid Services (CMS) emergency preparedness rule. This 2017 study focused on rural hospitals, critical access hospitals, and long‐term care facilities. An exploratory qualitative research study with an interpretive phenomenological approach was applied. Data were gathered from 11 face‐to‐face interviews with medical centers’ emergency and disaster planners in Northwest Missouri. Several categories and subcategories were identified in the data and developed into themes. Thematic analysis indicated significant barriers, including a CMS unfunded mandate, preparedness conducted by a single individual with other duties, lack of a whole community approach, and a lack of financial planning by medical center administration, hinder compliance with the CMS rule, necessary to mitigate nationwide emergencies. All participants agreed to the development of the emergency operations plan, which is essential for compliance. The findings from this study support the need for additional planning staff, time, and training to understand the elements of preparedness. Compliance with the CMS emergency preparedness rule cannot be achieved unless identified barriers are addressed.
Sediment and soil organic carbon loss during continuous extreme scouring events on the Loess Plateau
Authors: Zhang Yi , Li Peng , Liu Xiaojun , Xiao Lie , Chang Enhao , Su Yuanyi , Zhang Jianwen , Liu Zhan
Published: October 2020

The frequency of extreme hydrological events highlights the need to establish an empirical model of soil organic carbon (SOC) loss based on hydraulic characteristics. This model would aid in understanding and mitigating excessive SOC loss (SOCL) on the Loess Plateau, where severe erosion occurs. To construct such a model, we established five study plots of similar slope in the Loess Plateau: four experimental vegetation successional communities and one bare land control. An in situ field scouring experiment was carried out to measure and analyze soil erosion, hydraulic parameters, and SOCL. The first scour saw the greatest increase in sediment concentration (0.007 g ml−1) and sediment amount (2.886 kg) and the most significant SOC loss (8.361 g). Further scouring in each plot decreased total SOCL. The factors affecting SOCL included soil erodibility (median particle size, sediment concentration, total sediment loss, SOC concentration, total SOCL) and hydrodynamics (runoff depth, power, velocity, and shear force), which accounted for 93 and 29% of SOCL. Flow velocity, especially 2 m from the bottom of the transition section (L2), was most closely correlated to SOC concentration (0.681; P < .05). Flow velocity affects selective migration of sand in sediment, thus affecting SOC concentration. We based our sediment and SOCL model on observed hydrodynamics, including V2 (flow velocity at L2) in said model. Predicted values supported measured values more precisely (R2 > .98). Our findings and developed model aid in predicting SOCL on slopes during severe erosion events.
Explained variation under the additive hazards model
Authors: Rava Denise , Xu Ronghui
Published: October 2020

We study explained variation under the additive hazards regression model for right‐censored data. We consider different approaches for developing such a measure, and focus on one that estimates the proportion of variation in the failure time explained by the covariates. We study the properties of the measure both analytically, and through extensive simulations. We apply the measure to a well‐known survival dataset as well as the linked surveillance, epidemiology, and end results‐Medicare database for prediction of mortality in early stage prostate cancer patients using high‐dimensional claims codes.
Ferulic Hydroxamic Acid Triazole Hybrids as Peptide Deformylase Inhibitors: Synthesis, Molecular Modelling and Biological Evaluation
Authors: Aneja Babita , Khan Parvez , Alam Shadab , Hasan Phool , Abid Mohammad
Published: October 2020

Design and development of peptide deformylase (PDF) inhibitors has gained attention as it is a highly conserved and specific enzyme for bacterial protein synthesis. This makes it a specific and attractive drug target. Therefore, based on the targeted drug‐discovery approach, a series of ferulic acid‐based nonpeptidic hydroxamic acid‐triazole hybrids was synthesized. All the semi‐synthetic compounds (8 a–p) were evaluated against a panel of Gram‐positive and Gram‐negative bacterial strains. Most of the compounds showed antibacterial activities against S. pneumoniae while few were active against E. coli. Among all, the compound 8 j showed strong potency against S. pneumoniae with IC50 value 34.57 μg/mL whereas for E. coli the observed IC50 was 66.20 μg/mL. Growth kinetics study showed the bacteriostatic nature of compound 8 j against S. pneumoniae. Interestingly, in the studied concentration range, no significant hemolysis or cytotoxicity was observed towards human cells, suggesting the non‐toxic nature of compound 8 j. Molecular docking studies showed that compound 8 j occupies the same active site where actinonin (a known inhibitor of PDF) binds and it also mimics the mode of interactions by offering significant interactions with the corresponding amino acid residues of PDF. The outcome of this study suggested the potential implications of the present scaffold for the development of antibacterial molecules targeting PDF.
Effect of Vesicle Structure on Catalytic Activity of Suzuki‐Miyaura Cross‐Coupling Reaction: Impact of Framework and Morphology
Authors: Song Kunpeng , Jiang Yaya , Zou Zhijuan
Published: October 2020

A novel hybrid porous polymer with hollow vesicle structure has been synthesized via Friedel‐Crafts alkylation reaction and solvent‐induced method. The resulting two‐dimensional networks are hierarchical porous materials with high Brunauer‐Emmett‐Teller (BET) surface area of 1582 m2 g−1. The vesicle structure directly influenced the activity and shaping the performance of the catalyst. The kinetic study reveals the special vesicle structure can enrich the substrates in a limit scope and increase the reaction rate. It has been demonstrated that the framework and morphology play a major role on the catalysts’ excellent performance in Suzuki–Miyaura cross‐coupling reaction of aryl chlorides. These findings help elucidate the mode action of the vesicle structure in the unrevealed Suzuki reaction mechanism of supports and the potential development of new morphology control catalysts.
AIE Infinite Coordination Polymer for Phosphate Ion Detection via Aggregation State Modulation
Authors: Yang Yang , Dong Jiaxuan , Li Huihui , Guo Dongyu , Yang Weiting , Pan Qinhe
Published: October 2020

Coordination polymers (CPs) with aggregation‐induced emission (AIE) have been widely applied to fluorescent sensing based on the strategy of electron or energy transfer. Novel strategies still need to be explored to promote the application of AIE CPs in fluorescent sensing. Herein, an infinite coordination polymer (ICP), synthesized from Zn2+, adenine and AIE ligand 4,4’‐diphenic acid (DPA), was used to detect phosphate ion (Pi) via aggregation state modulation. The ICP was decomposed in the presence of Pi due to the coordination of Pi with Zn2+, which disaggregated AIE ligand DPA along with fluorescence quenching. The ICP quantified Pi in the concentration range from 30 to 600 μM with a detection limit of 5 μM, which was much lower than the physiological level, and was applied to detecting Pi in urine with spiked recoveries in the range of 82.0–115.5 %. This work provides a novel strategy to design fluorescent probes with AIE CPs for the analytes exhibiting the decomposing ability, promoting the application of AIE CPs in fluorescent sensing.
Bottom‐Up Synthesis of MoS2/CNTs Hollow Polyhedron with 1T/2H Hybrid Phase for Superior Potassium‐Ion Storage
Authors: Wu Kuan , Cao Xu , Li Minyue , Lei Bo , Zhan Jing , Wu Minghong
Published: October 2020

Enslaved to the large‐size K‐ions, the construction of suitable anode materials with superior and stable potassium‐ion storage properties is a major challenge. 1T phase MoS2 possesses higher conductivity, bigger interlayer distance, and more electrochemically active sites than the 2H phase, which offers intriguing benefits for energy‐related applications. In this work, the 1T/2H‐phase hybrid MoS2 nanosheets are successfully anchored in the N‐doped carbon nanotube hollow polyhedron (1T/2H‐MoS2/NCNHP) by a bottom‐up solvothermal method. For the synthesized 1T/2H‐MoS2/NCNHP, the fewer‐layer 1T/2H‐MoS2 nanosheets are embedded in an N‐doped carbon nanotube hollow polyhedron, with an enlarged interlayer spacing of 0.96 nm. When evaluated as anode material for potassium‐ion batteries, the 1T/2H‐MoS2/NCNHP hybrid presents outstanding potassium storage performance. It delivers a high‐specific capacity of 519.2 mAh g−1 at 50 mA g−1 and maintains 281.2 mAh g−1 at 1 A g−1 over 500 cycles. The good potassium‐ion electrochemical performance is attributed to the rational structural design and the synergistic effect of the components. Moreover, the 1T‐MoS2 nanosheet has excellent electrical conductivity and its enlarged interlayer spacing reduces the barrier for the embedding and stripping of K ions. Finally, the practical application of the 1T/2H‐MoS2/NCNHP electrode material is also evaluated by assembled K‐ion full cells.
Motion‐based design of vibrating civil engineering structures under uncertainty conditions
Authors: Jiménez‐Alonso Javier Fernando , Naranjo‐Perez Javier , Díaz Iván M. , Sáez Andrés
Published: October 2020

Improvements in the strength of construction materials, together with the esthetic requirements demanded by current societies, have led to a continuous increase in the slenderness of modern civil engineering structures. This fact results into lightweight designs that, unfortunately, must cope with two key problems: (a) slender structures are not only prone to vibrate under external actions; but (b) their dynamic behavior becomes also more sensitive to the intrinsic variability of the operational and environmental service conditions. These two circumstances must be faced from the early conceptual design phase of the structure. With the aim to assist in this process, a motion‐based design method, under a stochastic approach, is proposed, implemented and validated in this paper. In our proposal, the conceptual design problem is transformed into the combination of two coupled subproblems, involving an optimization subproblem plus a reliability analysis subproblem. The performance of the proposed method is illustrated via its application to a numerical case study involving the optimal design of two tuned mass dampers, installed to control the pedestrian‐induced vibrations in a cable‐stayed footbridge with prestressed concrete deck.
Temperature‐driven fatigue life of reinforced concrete integral bridge pile considering nonlinear soil–structure interaction
Authors: Verma Manoj , Mishra Shambhu Sharan
Published: October 2020

In this study, a five‐span fully integral reinforced concrete (RC) bridge has been investigated for fatigue life assessment of its RC piles considering the effects of environmental temperature variation and nonlinear soil characteristics. The effect of daily temperature variation on the abutment wall and pile foundation has been estimated. Multilayers of soil along the abutment pile depth have been considered in the formulations. The soil has been represented as 3D nonlinear springs. A new fatigue model has been used for crack initiation and propagation in the RC piles. In this model, a crack has been assumed to progress successively in three stages from the tension side of the pile. Finite element (FE)‐based modeling and analyses have been carried out to determine the longitudinal displacements and bending moment in piles, abutments, and piers. Furthermore, taking the bending moment as input crack mouth opening distance, crack propagation and fatigue life of pile have been assessed using the FE method‐based software. It is seen that the abutment piles suffer fatigue damage earlier as compared to the pier‐piles as a result of thermal and vehicular loads effects. Also, thermal fluctuation has shown little or no fluctuations in the longitudinal displacements of abutment and piles in the multispan fully integral bridge (FIB). It is expected that the proposed method will be helpful for the bridge engineers in designing the pile foundation passing through multiple soil layers against fatigue damage of a FIB in particular subjected to thermal and vehicular loading.
An Embattled Yet Enduring Influence: Introduction to a Special Issue on Blumerian Symbolic Interactionism
Authors: Low Jacqueline , Bowden Gary
Published: October 2020

The papers in this special issue celebrate and build on the insights Blumer provides in his pivotal book Symbolic Interactionism: Perspective and Method. In setting the context for these papers, we discuss the significance of Blumer's variant of interactionism, his contributions to the discipline of sociology, the misinterpretations and misrepresentations of his approach, and the way in which the papers in this issue carry forward his legacy.
Agriculture, economics, ecology and trade: A way forward for better world
Authors: Madiga Bala Dastagiri , Padigapati Venkata Naga Sindhuja , Suresh Rakesh , Mude Ramesh Naik
Published: October 2020

Very minute changes in the ecological conditions have a larger impact on the agriculture, trade and economy. This is a new perspective paper focusing more on next generation innovations in Agriculture, Economy, Ecology and Trade for better world. There is need to drive the economic growth so that nonrenewable resources do not trigger irreversible damage to the environmental resources and menace the welfare of the future generations. Integration of the environment policies, trade practices and individual actions must be enhanced for environment reliable technology and innovative solutions, which are necessary to determine the viability of the future in our planet. Radio Frequency Identification Technology, soil and water sensors, NL5000 G5, precision agriculture, bio‐security, robotic solutions, mobile technology, cloud computing, pervasive automation, block chain technology; e‐agriculture and environmental security measures are the new emerging latest technologies, which enhance the economic growth by integrating the trade, ecology and agriculture. Modern and innovative world is the only option to meet all the goals in the agriculture sector. These technologies make the agriculture more profitable, safe, efficient, and eco‐ friendly. Farmers need to improve themselves to be well skilled in using innovative technologies. Government should support investments in the agriculture and ecology.
Towards machine learning analytics for jet substructure
Authors: Kasieczka Gregor , Marzani Simone , Soyez Gregory , Stagnitto Giovanni
Published: October 2020

Abstract

The past few years have seen a rapid development of machine-learning algorithms. While surely augmenting performance, these complex tools are often treated as black-boxes and may impair our understanding of the physical processes under study. The aim of this paper is to move a first step into the direction of applying expert-knowledge in particle physics to calculate the optimal decision function and test whether it is achieved by standard training, thus making the aforementioned black-box more transparent. In particular, we consider the binary classification problem of discriminating quark-initiated jets from gluon-initiated ones. We construct a new version of the widely used N-subjettiness, which features a simpler theoretical behaviour than the original one, while maintaining, if not exceeding, the discrimination power. We input these new observables to the simplest possible neural network, i.e. the one made by a single neuron, or perceptron, and we analytically study the network behaviour at leading logarithmic accuracy. We are able to determine under which circumstances the perceptron achieves optimal performance. We also compare our analytic findings to an actual implementation of a perceptron and to a more realistic neural network and find very good agreement.
The JIMWLK evolution and the s-channel unitarity
Authors: Kovner Alex , Levin Eugene , Li Ming , Lublinsky Michael
Published: October 2020

Abstract

Further developing ideas set forth in [1], we discuss QCD Reggeon Field Theory (RFT) and formulate restrictions imposed on its Hamiltonian by the unitarity of underlying QCD. We identify explicitly the QCD RFT Hilbert space, provide algebra of the basic degrees of freedom (Wilson lines and their duals) and the algorithm for calculating the scattering amplitudes. We formulate conditions imposed on the “Fock states” of RFT by unitary nature of QCD, and explain how these constraints appear as unitarity constraints on possible RFT hamiltonians that generate energy evolution of scattering amplitudes. We study the realization of these constraints in the dense-dilute limit of RFT where the appropriate Hamiltonian is the JIMWLK Hamiltonian HJIMWLK. We find that the action HJIMWLK on the dilute projectile states is unitary, but acting on dense “target” states it violates unitarity and generates states with negative probabilities through energy evolution.
Neurologische Komplikationen der Hepatitis-C-Infektion
Authors: Kleefeld Felix , Arendt Gabriele , Neuen-Jacob Eva , Maschke Matthias , Husstedt Ingo , Obermann Mark , Schmidt Holger , Hahn Katrin ,   Deutsche Gesellschaft für Neuro-AIDS und Neuro-Infektiologie (DGNANI)
Published: October 2020

Die chronische Hepatitis-C-Virus(HCV)-Infektion ist eine hochprävalente Systemerkrankung, die verschiedene neurologische Komplikationen verursachen kann. Es lassen sich HCV-assoziierte Symptome im zentralen und peripheren Nervensystem sowie der Muskulatur unterscheiden. Wichtige Pathomechanismen sind die HCV-assoziierte Autoimmunität (z. B. gemischte Kryoglobulinämie mit Polyneuropathie) und direkte Neurotoxizität (z. B. bei HCV-assoziierten kognitiven Defiziten). Die häufigsten neurologischen Komplikationen sind distal-symmetrische Polyneuropathien, Small-fiber-Neuropathien und kognitive Defizite. Die HCV-Infektion stellt außerdem einen Risikofaktor für ischämische und hämorrhagische Schlaganfälle sowie den Morbus Parkinson dar. Die frühe Identifikation und antivirale Behandlung HCV-positiver Patienten steht im Zentrum der Behandlung. Durch neue antivirale Therapien können >90 % der Patienten dauerhaft von der HCV-Infektion geheilt werden.
Clinical and radiological hip parameters do not precede, but develop simultaneously with cam morphology: a 5-year follow-up study
Authors: van Klij P. , Heijboer M. P. , Ginai A. Z. , Verhaar J. A. N. , Waarsing J. H. , Agricola R.
Published: October 2020

Purpose

The aim of this study was to (1) investigate whether radiographic and clinical parameters, which influence how stresses during sporting activities act on the proximal femur, are associated with cam morphology or (2) precede cam morphology development.

Methods

Young male football players participated at baseline (n = 89, 12–19 years of age), 2.5-year (n = 63) and 5-year follow-up (n = 49). Standardized anteroposterior pelvic and frog-leg lateral radiographs were obtained at each time-point. Cam morphology was quantified by an alpha angle ≥ 60°, and large cam morphology ≥ 78°. The neck–shaft angle (NSA), epiphyseal extension (EE), lateral center–edge angle (LCEA) and hip internal rotation (IR) were also measured. Cross-sectional associations between NSA, EE, LCEA and IR and (large) cam morphology were studied at all time-points. To study whether these variables preceded cam morphology development, hips without cam morphology at baseline were studied prospectively.

Results

A lower NSA, a higher EE and limited IR were consistently associated with cam morphology at all three time-points. These differences were more pronounced in hips with large cam morphology. No association between cam morphology and the LCEA was found. None of the parameters studied preceded cam morphology development.

Conclusion

Cam morphology developed simultaneously with a varus orientation, growth plate extension towards the femoral neck and limited hip internal rotation. These parameters did not precede cam morphology development. The hip parameters studied cannot be used to identify individuals at risk of developing cam morphology.

Level of Evidence:

Level II.
Investigation into the turbulence statistics of installed jets using hot-wire anemometry
Authors: Proença Anderson , Lawrence Jack , Self Rod
Published: October 2020

This work presents a detailed study of the turbulence flow statistics of a jet mounted with its axis parallel to a rigid flat plate. Hot-wire constant temperature anemometry has been used to measure the single-point and two-point statistics of the axial velocity component at several locations within the jet flow field. Results show that the jet mean flow near the plate surface is subjected to a local acceleration and redirection due to a Coandă-type effect. The propagation of these effects downstream of the plate trailing edge is strongly dependent on the plate position. Regarding the velocity fluctuations, the mean turbulence intensity levels are seen to decrease as the radial distance between the jet and surface decreases. Analysis of the single-point power spectral density data on the shear layer close to the plate shows that the reduction in magnitude of the low-frequency content of the energy spectrum is responsible for the decrease in turbulence intensity. Additionally, the characteristic time and length scales computed from two-point measurements reduce as the plate is mounted closer to the jet centre-line. The axial eddy convection velocity is seen to increase in the region of high turbulent kinetic energy in the shear layer adjacent to the surface. Empirical models for turbulence characteristic scales and eddy convection velocity are presented. These findings suggest that both the amplitude and distribution of the jet mixing noise sources are affected when closely installed next to a surface. This paper is a continuation of a recent investigation on the turbulence statistics of isolated jets presented in Proença (Exp Fluids 60(4):63, 2019).

Graphic abstract
Groundwater flow below construction pits and erosion of temporary horizontal layers of silicate grouting
Authors: Dekker Joris M. , Sweijen Thomas , Zech Alraune
Published: October 2020

Injection of silicate grouting materials is widely used to create temporary horizontal layers for reducing inflow of groundwater at construction sites, in regions with shallow water tables. The erosion of a grouting layer was investigated by means of analytical solutions for groundwater flow and transport within a pit after construction finished. Erosion is assumed to occur by dissolution of the temporary injection layer and subsequent advective transport. Thereby, the hydraulic conductivity changes with time. This paper presents novel analytical solutions and approximate solutions for the major fluxes in the construction pit as a function of the domain settings, aquifer gradient and hydraulic conductivity. In addition, the mass flux and the dilution ratio of erosion-related components leaving the construction pit and entering the aquifer are quantified. Derived solutions are verified against numerical simulations. A sensitivity study shows the impact of domain settings on fluxes and dilution ratio. The results confirm that mass flux of grout components increases with ongoing erosion. Thus, its effect on groundwater quality increases with time after construction ceased.
An optimal monotone contention resolution scheme for bipartite matchings via a polyhedral viewpoint
Authors: Bruggmann Simon , Zenklusen Rico
Published: October 2020

Relaxation and rounding approaches became a standard and extremely versatile tool for constrained submodular function maximization. One of the most common rounding techniques in this context are contention resolution schemes. Such schemes round a fractional point by first rounding each coordinate independently, and then dropping some elements to reach a feasible set. Also the second step, where elements are dropped, is typically randomized. This leads to an additional source of randomization within the procedure, which can complicate the analysis. We suggest a different, polyhedral viewpoint to design contention resolution schemes, which avoids to deal explicitly with the randomization in the second step. This is achieved by focusing on the marginals of a dropping procedure. Apart from avoiding one source of randomization, our viewpoint allows for employing polyhedral techniques. Both can significantly simplify the construction and analysis of contention resolution schemes. We show how, through our framework, one can obtain an optimal monotone contention resolution scheme for bipartite matchings, which has a balancedness of 0.4762. So far, only very few results are known about optimality of monotone contention resolution schemes. Our contention resolution scheme for the bipartite case also improves the lower bound on the correlation gap for bipartite matchings. Furthermore, we derive a monotone contention resolution scheme for matchings that significantly improves over the previously best one. More precisely, we obtain a balancedness of 0.4326, improving on a prior 0.1997-balanced scheme. At the same time, our scheme implies that the currently best lower bound on the correlation gap for matchings is not tight. Our results lead to improved approximation factors for various constrained submodular function maximization problems over a combination of matching constraints with further constraints.
Drag Distribution in Idealized Heterogeneous Urban Environments
Authors: Sützl Birgit S. , Rooney Gabriel G. , van Reeuwijk Maarten
Published: October 2020

Large-eddy simulations of nine idealized heterogeneous urban morphologies with identical building density and frontal area index are used to explore the impact of heterogeneity on urban airflow. The fractal-like urban morphologies were generated with a new open-source Urban Landscape Generator tool (doi:10.5281/zenodo.3747475). The vertical structure of mean flow and the dispersive vertical momentum transport within the roughness sublayer are shown to be strongly influenced by the building morphologies. The friction velocity and displacement height show high correlations with the maximum building height rather than the average height. Well-known roughness parametrizations of the logarithmic layer cannot adequately capture the large spread observed in the large-eddy simulation data. A generalized frontal area index $${\Lambda }_f$$

Λ
f

is introduced that characterizes the vertical distribution of the frontal area in the urban canopy. The vertically distributed stress profiles, which differ significantly per simulation, are shown to roughly collapse upon plotting them against $${\Lambda }_f$$

Λ
f

. The stress distribution representing urban drag can be fitted with a third degree polynomial. The results can be used for more detailed and robust representations of building effects in the development of urban canopy models.
Determinants of pain in advanced HCC patients recieving hepatic artery infusion chemotherapy
Authors: Wu Zhiqiang , Guo Wenbo , Chen Song , Zhuang Wenquan
Published: October 2020

Purpose Hepatic arterial infusion chemotherapy (HAIC) is one of the options to treat unresectable hepatocellular carcinoma (HCC). The majority of HCC patients suffer great pain in the course of HAIC treatment. To improve the quality of life and the efficacy of HAIC treatment, the causes of pain, the choice of an analgesic regimen, and the relationship between pain and prognosis of HCC were analyzed. Methods A total of 376 HCC patients under HAIC in our hospital were recriuted between March 2017 and September 2019. Multivariate linear regression analysis (stepwise) was used to calculate the potential factors related to the severe pain in HCC patients under HAIC. Analgesics treatments were carried out based on the results of the visual analogue scale (VAS) score which was used to evaluate the pain. Results The mean value of the VAS score is 3.604, which indicates that the pain in most patients is mild and endurable. Intra-arterial lidocaine injection is an effective method in most patients (96%, 361 of 376), and the total score of VAS is reduced from 1355 to 195 following lidocaine injection. Multivariate analysis suggestes that oxaliplatin (OXA) preparation time, hepatic artery diameter and OXA manufacturers (R2 = 0.859) are influential factors for pain scores. Conclusion This study demonstrates an effective way to systematically assess and ease pain in HCC patients with HAIC treatment. OXA preparation time, hepatic artery diameter, and OXA manufacturers are the potential influencing factors for pain. This work presented here will provide a detailed understanding of the clinical application of HAIC in advanced HCC patients.
Comparative judgement, proof summaries and proof comprehension
Authors: Davies Ben , Alcock Lara , Jones Ian
Published: October 2020

Proof is central to mathematics and has drawn substantial attention from the mathematics education community. Yet, valid and reliable measures of proof comprehension remain rare. In this article, we present a study investigating proof comprehension via students’ summaries of a given proof. These summaries were evaluated by expert judges making pairwise comparisons, which were used to generate a score for each summary. This approach, known as comparative judgement, has been demonstrated to generate reliable and valid scores when assessing other mathematical constructs. Our findings suggest that comparative judgement can produce valid and reliable assessments of the quality of student-produced proof summaries. We also explored which features of students’ proof summaries were most valued by the expert judges, and found that high-scoring summaries referenced a proof’s logical structure and the mechanism by which it reached a contradiction.
Barth syndrome cardiomyopathy: targeting the mitochondria with elamipretide
Authors: Sabbah Hani N.
Published: October 2020

Barth syndrome (BTHS) is a rare, X-linked recessive, infantile-onset debilitating disorder characterized by early-onset cardiomyopathy, skeletal muscle myopathy, growth delay, and neutropenia, with a worldwide incidence of 1/300,000–400,000 live births. The high mortality rate throughout infancy in BTHS patients is related primarily to progressive cardiomyopathy and a weakened immune system. BTHS is caused by defects in the TAZ gene that encodes tafazzin, a transacylase responsible for the remodeling and maturation of the mitochondrial phospholipid cardiolipin (CL), which is critical to normal mitochondrial structure and function (i.e., ATP generation). A deficiency in tafazzin results in up to a 95% reduction in levels of structurally mature CL. Because the heart is the most metabolically active organ in the body, with the highest mitochondrial content of any tissue, mitochondrial dysfunction plays a key role in the development of heart failure in patients with BTHS. Changes in mitochondrial oxidative phosphorylation reduce the ability of mitochondria to meet the ATP demands of the human heart as well as skeletal muscle, namely ATP synthesis does not match the rate of ATP consumption. The presence of several cardiomyopathic phenotypes have been described in BTHS, including dilated cardiomyopathy, left ventricular noncompaction, either alone or in conjunction with other cardiomyopathic phenotypes, endocardial fibroelastosis, hypertrophic cardiomyopathy, and an apical form of hypertrophic cardiomyopathy, among others, all of which can be directly attributed to the lack of CL synthesis, remodeling, and maturation with subsequent mitochondrial dysfunction. Several mechanisms by which these cardiomyopathic phenotypes exist have been proposed, thereby identifying potential targets for treatment. Dysfunction of the sarcoplasmic reticulum Ca2+-ATPase pump and inflammation potentially triggered by circulating mitochondrial components have been identified. Currently, treatment modalities are aimed at addressing symptomatology of HF in BTHS, but do not address the underlying pathology. One novel therapeutic approach includes elamipretide, which crosses the mitochondrial outer membrane to localize to the inner membrane where it associates with cardiolipin to enhance ATP synthesis in several organs, including the heart. Encouraging clinical results of the use of elamipretide in treating patients with BTHS support the potential use of this drug for management of this rare disease.
Theoretical study of the phase transitions and electronic structure of (Zr0.5, Mg0.5)N and (Hf0.5, Mg0.5)N
Authors: Gharavi M. A. , Armiento R. , Alling B. , Eklund P.
Published: October 2020

Rock-salt scandium nitride has gained interest due to its thermoelectric properties including a relatively high Seebeck coefficient. This motivates research for other semiconductor materials that exhibit similar electronic structure features as ScN. Using density functional theory calculations, we have studied disordered solid solutions of (Zr0.5, Mg0.5)N and (Hf0.5, Mg0.5)N using the special quasi-random structure model. The results show that within a mean-field approximation for the configurational entropy, the order–disorder phase transformation between the monoclinic LiUN2 prototype structure and the rock-salt cubic random alloy of these mentioned solid solutions occur at 740 K and 1005 K for (Zr0.5, Mg0.5)N and (Hf0.5, Mg0.5)N, respectively. The density-of-states for the two ternary compounds is also calculated and predicts semiconducting behavior with band gaps of 0.75 eV for (Zr0.5, Mg0.5)N and 0.92 eV for (Hf0.5, Mg0.5)N. The thermoelectric properties of both compounds are also predicted. We find that in the range of a moderate change in the Fermi level, a high Seebeck coefficient value at room temperature can be achieved.
Structural Characterization of Two Polymorphs of 1-(4-Methylpyridin-2-yl)thiourea and Two Derived 2-Aminothiazoles
Authors: Böck Denise , Beuchel Andreas , Goddard Richard , Imming Peter , Seidel Rüdiger W.
Published: October 2020

Two polymorphic forms of 1-(4-methylpyridin-2-yl)thiourea (1) and the crystal and molecular structures of the 2-aminothiazoles N-(4-methylpyridin-2-yl)-4-(pyridin-2-yl)thiazol-2-amine (2) and N-(4-methylpyridin-2-yl)-4-(pyrazin-2-yl)thiazol-2-amine (3), derived from 1 and the respective α-bromoketone via the Hantzsch reaction, are described. Both polymorphic forms 1α (space group P21/c, Z = 4) and 1β (space group P21/n, Z = 8) crystallize in the monoclinic system but exhibit distinctly different intermolecular hydrogen bonding patterns. Compound 2 (orthorhombic, space group Pca21, Z = 8) forms polymeric N–H⋯N hydrogen-bonded zigzag tapes in the polar crystal structure, with a significant twisting between the thiazole and pyridine rings. In contrast, the crystal structure of 3 (monoclinic, space group P21/c, Z = 4) features nearly planar centrosymmetric N–H⋯N hydrogen-bonded dimers, which are laterally joined through long C–H⋯N contacts, affording a π⋯π stacked layered structure.

Graphic Abstract

Two polymorphs of 1-(4-methylpyridin-2-yl)thiourea and the crystal and molecular structures of two 2-aminothiazoles, derived from 1-(4-methylpyridin-2-yl)thiourea and α-bromoketones via Hantzsch reaction, are reported.
Modeling the Depositional Environment of the Sandstone Reservoir in the Middle Miocene Sidri Member, Badri Field, Gulf of Suez Basin, Egypt: Integration of Gamma-Ray Log Patterns and Petrographic Characteristics of Lithology
Authors: Radwan Ahmed E.
Published: October 2020

Understanding the depositional setting of siliciclastics reservoir is fundamental process to exploration and development of hydrocarbon reservoirs and to the multi-phase cycle of the oil and gas industry. Typically, core samples from existing or potential reservoirs can be used for interpretation of depositional environment. However, the lack of core samples in certain reservoirs represents a challenge for reservoir development plans and further exploration. To overcome the absence of core samples in the middle Miocene Sidri Member in the Badri field, Gulf of Suez, this study aimed to reconstruct its depositional settings by coupling well logging patterns and petrographic characterization of ditch cuttings. Consequently, 30 thin section samples representing the reservoir section of four wells were described in detail and standard petrographic characteristics were determined. Then, gamma-ray (GR) log patterns of the studied reservoir wells were used for interpretation of depositional environment. Petrographic analysis indicates that the sandstone reservoir is fine- to medium-grained arkose with dominant siliceous cement and composed mainly of quartz, feldspars, and lithic fragments. Pores reflecting primary and secondary porosity as well as inter-granular pores are dominant. The facies analysis indicates that the studied member has a heterogeneous nature and rapid facies change; its main lithofacies are blocky sandstones, intercalated sandstones and shales, and shales. Three electrofacies were interpreted in the studied section: (1) electrofacies-A (blocky sandstones), which is characterized by a cylindrical-shaped (right boxcar) GR trend; (2) electrofacies-B (intercalated sandstones and shales), which is characterized by an irregular log trend with serrated shape; and (3) electrofacies-C (shales), which is characterized by irregular GR trend and has no character. The interpreted results indicate a tidal channel depositional setting for electrofacies-A, mixed tidal flat depositional setting for electrofacies-B, and low relief offshore mudstone depositional setting for electrofacies-C. Finally, the results illustrate how the coupling of GR patterns with the analysis of petrographic characteristics can be used to understand the depositional setting of a hydrocarbon reservoir that lacks core samples. This work could be useful for assessment of reservoir distribution and quality, for reduction of uncertainty during field development, as well as for providing useful insight to similar hydrocarbon reservoirs elsewhere.
Interpreting, analysing and modelling COVID-19 mortality data
Authors: Sornette Didier , Mearns Euan , Schatz Michael , Wu Ke , Darcet Didier
Published: October 2020

We present results on the mortality statistics of the COVID-19 epidemic in a number of countries. Our data analysis suggests classifying countries in five groups, (1) Western countries, (2) East Block, (3) developed Southeast Asian countries, (4) Northern Hemisphere developing countries and (5) Southern Hemisphere countries. Comparing the number of deaths per million inhabitants, a pattern emerges in which the Western countries exhibit the largest mortality rate. Furthermore, comparing the running cumulative death tolls as the same level of outbreak progress in different countries reveals several subgroups within the Western countries and further emphasises the difference between the five groups. Analysing the relationship between deaths per million and life expectancy in different countries, taken as a proxy of the preponderance of elderly people in the population, a main reason behind the relatively more severe COVID-19 epidemic in the Western countries is found to be their larger population of elderly people, with exceptions such as Norway and Japan, for which other factors seem to dominate. Our comparison between countries at the same level of outbreak progress allows us to identify and quantify a measure of efficiency of the level of stringency of confinement measures. We find that increasing the stringency from 20 to 60 decreases the death count by about 50 lives per million in a time window of 20  days. Finally, we perform logistic equation analyses of deaths as a means of tracking the dynamics of outbreaks in the “first wave” and estimating the associated ultimate mortality, using four different models to identify model error and robustness of results. This quantitative analysis allows us to assess the outbreak progress in different countries, differentiating between those that are at a quite advanced stage and close to the end of the epidemic from those that are still in the middle of it. This raises many questions in terms of organisation, preparedness, governance structure and so on.
Challenges of Implementing a Performance and Reward System in Higher Education Institutions in Pakistan: Perceptions of Top Leaders in Contending Regulatory Bodies
Authors: Khan Tayyeb Ali , Christensen Tom
Published: October 2020

This article is a study of the challenges of implementing a performance and rewards management system for academics (Tenure Track System - TTS) in Pakistan over the last decade. The main empirical focus is on the perceptions of the leading implementer, the Higher Education Commission (HEC). These are supplemented by the perceptions of the Provincial Higher Education Commission (PHEC) in Punjab. Semi-structured interviews and document analysis were the two methods used to collect data. The study is based on two perspectives from organizational theory, a structural and a cultural perspective. The main findings highlight how leaders implemented TTS despite its incompatibility with the structure and culture of public universities in Pakistan. The study also revealed tensions between two reward systems – BPS and TTS – as well as the effects of the 18th constitutional amendment on the implementation of higher education programs. This study contributes insights into the reform of the higher education system in developing countries in the context of NPM.
Paradigms and paradoxes: decoding the “genetic code”
Authors: Knabel Stephen John , Hargittai Istvan
Published: October 2020

We propose to keep the term “genetic code” to describe the nucleotide sequence in DNA and RNA and use the term “genetic cipher” to describe the key for decoding the genetic codes of DNA and RNA into the amino acid sequences of proteins.
Analyzing temporal patterns of topic diversity using graph clustering
Authors: Hashimoto Takako , Shepard David Lawrence , Kuboyama Tetsuji , Shin Kilho , Kobayashi Ryota , Uno Takeaki
Published: October 2020

During a disaster, social media can be both a source of help and of danger: Social media has a potential to diffuse rumors, and officials involved in disaster mitigation must react quickly to the spread of rumor on social media. In this paper, we investigate how topic diversity (i.e., homogeneity of opinions in a topic) depends on the truthfulness of a topic (whether it is a rumor or a non-rumor) and how the topic diversity changes in time after a disaster. To do so, we develop a method for quantifying the topic diversity of the tweet data based on text content. The proposed method is based on clustering a tweet graph using Data polishing that automatically determines the number of subtopics. We perform a case study of tweets posted after the East Japan Great Earthquake on March 11, 2011. We find that rumor topics exhibit more homogeneity of opinions in a topic during diffusion than non-rumor topics. Furthermore, we evaluate the performance of our method and demonstrate its improvement on the runtime for data processing over existing methods.
Historical Trends in Children Living in Multigenerational Households in the United States: 1870–2018
Authors: Pilkauskas Natasha V. , Amorim Mariana , Dunifon Rachel E.
Published: October 2020

Over the last two decades, the share of U.S. children under age 18 who live in a multigenerational household (with a grandparent and parent) has increased dramatically. Yet we do not know whether this increase is a recent phenomenon or a return to earlier levels of coresidence. Using data from the decennial census from 1870 to 2010 and the 2018 American Community Survey, we examine historical trends in children’s multigenerational living arrangements, differences by race/ethnicity and education, and factors that explain the observed trends. We find that in 2018, 10% of U.S. children lived in a multigenerational household, a return to levels last observed in 1950. The current increase in multigenerational households began in 1980, when only 5% of children lived in such a household. Few differences in the prevalence of multigenerational coresidence by race/ethnicity or education existed in the early part of the twentieth century; racial/ethnic and education differences in coresidence are a more recent phenomena. Decomposition analyses do little to explain the decline in coresidence between 1940 and 1980, suggesting that unmeasured factors explain the decrease. Declines in marriage and in the share of White children most strongly explained the increase in multigenerational coresidence between 1980 and 2018. For White children with highly educated parents, factors explaining the increase in coresidence differ from other groups. Our findings suggest that the links between race/ethnicity and socioeconomic status and multigenerational coresidence have changed over time, and today the link between parental education and coresidence varies within racial/ethnic groups.