bluuebunny/crossref_metadata_2025 huggingface dataset:
Randomized estimation of functional covariance operator via subsampling
Authors: He Shiyuan , Yan Xiaomeng
Published: August 2020

Covariance operators are fundamental concepts and modelling tools for many functional data analysis methods, such as functional principal component analysis. However, the empirical (or estimated) covariance operator becomes too costly to compute when the functional dataset gets big. This paper studies a randomized algorithm for covariance operator estimation. The algorithm works by sampling and rescaling observations from the large functional data collection to form a sketch of much smaller size and performs computation on the sketch to obtain the subsampled empirical covariance operator. The proposed algorithm is theoretically justified via nonasymptotic bounds between the subsampled and the full‐sample empirical covariance operator in terms of the Hilbert‐Schmidt norm and the operator norm. It is shown that the optimal sampling probability that minimizes the expected squared Hilbert‐Schmidt norm of the subsampling error is determined by the norm of each function. Simulated and real data examples are used to illustrate the effectiveness of the proposed algorithm.
Preparation and Characterization Nanocrystalline Cellulose as a Food Additive to Produce Healthy Biscuit Cream
Authors: Asghari Mohsen , Karimi Zarchi Ali Akbar , Taheri Ramezan Ali
Published: August 2020

Nanocrystalline cellulose (CNC) has been extensively developed in various fields such as nanostructure and food systems enhancers. In this study, first a CNC is synthesized through a homogenizer–ultrasound technique plus acid hydrolysis and then its application in biscuit cream is investigated. The morphology results reveal the swelling capacity of the CNC increases 63%, over raw cellulose and the dynamic light scattering particle size is about 120 nm. The surface morphology results of the CNC shows a spherical shape with an average diameter of 89 nm. The results show an increase in the degree of crystallinity with decreasing thermal stability in the CNC. The best result of the oil stability associated with maintaining the sensory properties is related to the cream formulated with a 50:50 ratio of sunflower oil and shortening after being incorporated with CNCs. It is thus shown to be necessary to optimize the concentration of CNCs to control cream texture characteristics.
Inhibition of Long‐Term Retrogradation of Corn, Potato, and Pea Starches by Borax
Authors: Ji Na , Li Fang , Yu Mengting , Wang Yanfei , Xiong Liu , Sun Qingjie
Published: August 2020

This work aims to develop a new method for inhibiting the long‐term retrogradation of normal corn starch, waxy corn starch (WCS), potato starch, and pea starch with borax. Differential scanning calorimetry results indicate that adding borax clearly reduces the retrogradation enthalpies of the four starches and decreases the crystallization rate constant. The percentage of retrogradation of WCS combined with 5% borax decreases to 12.06% compared with 69.67% for retrograded WCS without borax after 28 d at 4 °C. Low‐field nuclear magnetic resonance analysis shows that borax remarkably decreases the spin–spin relaxation time of the four starches. The results demonstrate that borax can be used as a new inhibitor and can retard the long‐term retrogradation of starch.
Bond behavior of BFRP bars with basalt‐fiber reinforced cement‐based composite materials
Authors: Wang Yan , Li Zhenxing , Zhang Chuchu , Wang Xin , Li Jiang , Liang Yaozhe , Chu Shaohui
Published: August 2020

This study investigated the bond behavior of BFRP bars with basalt‐fiber cement‐based composite materials (BFRCC). The bond behavior was evaluated in terms of the bar type, bar diameter, matrix type, fiber volume, and spiral stirrup presence. The interface failures between the bars and matrix were observed after the experiment. The influence factors of the test groups on the bond‐slip mechanism were analyzed, and an analytical model of the bond‐slip mechanism was established by data fitting. The results show that the interface failures between the bars and the BFRCC matrix were divided into pull‐out failure and splitting failure, the bond‐slip curve had a residual stage and demonstrated periodic decay. Although the bars' diameters had little effect on the bond strength and average slip, the fiber volume strongly influenced it, and the spiral stirrup could effectively prevent splitting failure. A high‐precision bond‐slip model between the BFRP bars and basalt‐fiber cement‐based composite materials (BFRCC) was established.
Stabilization of non‐native polymorphs for electrocatalysis and energy storage systems
Authors: Saha Sulay , Gupta Prashant Kumar , Pala Raj Ganesh S.
Published: August 2020

Evolution in material centric devices like batteries and electrocatalytic reactors have predominantly been made possible via the exploitation of the thermodynamic ground state of pristine or defective bulk crystal, referred to as the “Native polymorph” (NP) here. A significant increase in the material search space is possible by utilizing “Non‐Native polymorphs (NNP),” which are materials that have different translational symmetry with respect to NP. As the NNP have a distinct coordination structure from that of the NP, critical material properties can be anticipated to be different, making NNP a potential substitute material for the aforementioned applications, which are the focus of this review. To obtain a structure–function relationship, systematic approaches to the synthesis of NNP has been demonstrated. Following certain generalities behind NNP, we classify synthesis techniques into few categories with the hope of rationalizing the underlying mechanism of these synthesis and stabilization strategies. We discuss the utility of NNPs in the context of electrochemical water electrocatalytic reactions. Typically, the NNPs have more open volume space enabling lower lithium‐ion diffusion barrier, higher lithium‐ion binding energies, thereby making NNP efficient in the context of energy storage material. However, NNP have lesser stability than the NP and methods to calibrate and improve the stability of NNP are important. Overall, the discussion of polymorphic materials by demarcating them as NP and NNP provides a systematic approach towards modulating material properties as a trade‐off between thermodynamics and kinetics of physicochemical processes. Finally, the challenges and perspectives in this emerging field are discussed.

This article is categorized under:

Fuel Cells and Hydrogen > Science and Materials

Energy Research & Innovation > Science and Materials

Energy and Development > Science and Materials
Stress analysis of a mode‐I crack in a 1D hexagonal quasicrystal based on the non‐local theory
Authors: Liu Hai‐Tao
Published: August 2020

This paper studies the non‐local theory solution of a Mode‐I crack in a 1D hexagonal quasicrystal (QC) by using the generalized Almansi's theorem and the Schmidt method. Based on the Fourier transform, the boundary value problem is reduced to two pairs of dual integral equations, in which the unknown variables are the displacement jumps across the crack surfaces. The dual integral equations are derived. Finally, the expression of the phonon stress field and the phason stress field at the crack tip are obtained. Numerical examples are provided to show the effects of the lattice parameter and the crack length on the phonon stress field and the phason stress field near the crack tip. Different from the classical solution, that the present solution exhibits no stress singularity at the crack tips in a 1D hexagonal QC.
Quantum chaos, thermodynamics and black hole microstates in the mass deformed SYK model
Authors: Nosaka Tomoki , Numasawa Tokiro
Published: August 2020

Abstract

We study various aspects of the mass deformation of the SYK model which makes the black hole microstates escapable. SYK boundary states are given by a simple local boundary condition on the Majorana fermions and then evolved in Euclidean time in the SYK Hamiltonian. We study the ground state of this mass deformed SYK model in detail. We also use SYK boundary states as a variational approximation to the ground state of the mass deformed SYK model. We compare variational approximation with the exact ground state results and they showed a good agreement. We also study the time evolution of the mass deformed ground state under the SYK Hamiltonian. We give a gravity interpretation of the mass deformed ground state and its time evolutions. In gravity side, mass deformation gives a way to prepare black hole microstates that are similar to pure boundary state black holes. Escaping protocol on these ground states simply gives a global AdS2 with an IR end of the world brane. We also study the thermodynamics and quantum chaotic properties of this mass deformed SYK model. Interestingly, we do not observe the Hawking Page like phase transition in this model in spite of similarity of the Hamiltonian with eternal traversable wormhole model where we have the phase transition.
The dark phases of the N2HDM
Authors: Engeln Isabell , Ferreira Pedro , Mühlleitner M. Margarete , Santos Rui , Wittbrodt Jonas
Published: August 2020

Abstract

We discuss the dark phases of the Next-to-2-Higgs Doublet model. The model is an extension of the Standard Model with an extra doublet and an extra singlet that has four distinct CP-conserving phases, three of which provide dark matter candidates. We discuss in detail the vacuum structure of the different phases and the issue of stability at tree-level of each phase. Taking into account the most relevant experimental and theoretical constraints, we found that there are combinations of measurements at the Large Hadron Collider that could single out a specific phase. The measurement of h125 → γγ together with the discovery of a new scalar with specific rates to τ+τ− or γγ could exclude some phases and point to a specific phase.
Loops and trees in generic EFTs
Authors: Craig Nathaniel , Jiang Minyuan , Li Ying-Ying , Sutherland Dave
Published: August 2020

Abstract

We consider aspects of tree and one-loop behavior in a generic 4d EFT of massless scalars, fermions, and vectors, with a particular eye to the high-energy limit of the Standard Model EFT at operator dimensions 6 and 8. First, we classify the possible Lorentz structures of operators and the subset of these that can arise at tree-level in a weakly coupled UV completion, extending the tree/loop classification through dimension 8 using functional methods. Second, we investigate how operators contribute to tree and one-loop helicity amplitudes, exploring the impact of non-renormalization theorems through dimension 8. We further observe that many dimension 6 contributions to helicity amplitudes, including rational parts, vanish exactly at one-loop level. This suggests the impact of helicity selection rules extends beyond one loop in non-supersymmetric EFTs.
On supersymmetric AdS4 orientifold vacua
Authors: Marchesano Fernando , Palti Eran , Quirant Joan , Tomasiello Alessandro
Published: August 2020

Abstract

In this work we study ten-dimensional solutions to type IIA string theory of the form AdS4×X6which contain orientifold planes and preserve$$ \mathcal{N} $$N= 1 supersymmetry. In particular, we consider solutions which exhibit some key features of the four-dimensional DGKT proposal for compactifications on Calabi-Yau manifolds with fluxes, and in this sense may be considered their ten-dimensional uplifts. We focus on the supersymmetry equations and Bianchi identities, and find solutions to these that are valid at the two-derivative level and at first order in an expansion parameter which is related to the AdS cosmological constant. This family of solutions is such that the background metric is deformed from the Ricci-flat one to one exhibiting SU(3) × SU(3)-structure, and dilaton gradients and warp factors are induced.
Finite size effects in classical string solutions of the Schrödinger geometry
Authors: Zoakos Dimitrios
Published: August 2020

Abstract

We study finite size corrections to the semiclassical string solutions of the Schrödinger spacetime. We compute the leading order exponential corrections to the infinite size dispersion relation of the single spin giant magnon and of the single spin single spike solutions. The solutions live in a S3 subspace of the five-sphere and extent in the Schrödinger part of the metric. In the limit of zero deformation the finite size dispersion relations flow to the undeformed AdS5 × S5 counterparts and in the infinite size limit the correction term vanishes and the known infinite size dispersion relations are obtained.
Spontaneous baryogenesis from axions with generic couplings
Authors: Domcke Valerie , Ema Yohei , Mukaida Kyohei , Yamada Masaki
Published: August 2020

Abstract

Axion-like particles can source the baryon asymmetry of our Universe through spontaneous baryogenesis. Here we clarify that this is a generic outcome for essentially any coupling of an axion-like particle to the Standard Model, requiring only a non-zero velocity of the classical axion field while baryon or lepton number violating interactions are present in thermal bath. In particular, coupling the axions only to gluons is sufficient to generate a baryon asymmetry in the presence of electroweak sphalerons or the Weinberg operator. Deriving the transport equation for an arbitrary set of couplings of the axion-like particle, we provide a general framework in which these results can be obtained immediately. If all the operators involved are efficient, it suffices to solve an algebraic equation to obtain the final asymmetries. Otherwise one needs to solve a simple set of differential equations. This formalism clarifies some theoretical subtleties such as redundancies in the axion coupling to the Standard Model particles associated with a field rotation. We demonstrate how our formalism automatically evades potential pitfalls in the calculation of the final baryon asymmetry.
Hormonal axes in Drosophila: regulation of hormone release and multiplicity of actions
Authors: Nässel Dick R. , Zandawala Meet
Published: August 2020

Hormones regulate development, as well as many vital processes in the daily life of an animal. Many of these hormones are peptides that act at a higher hierarchical level in the animal with roles as organizers that globally orchestrate metabolism, physiology and behavior. Peptide hormones can act on multiple peripheral targets and simultaneously convey basal states, such as metabolic status and sleep-awake or arousal across many central neuronal circuits. Thereby, they coordinate responses to changing internal and external environments. The activity of neurosecretory cells is controlled either by (1) cell autonomous sensors, or (2) by other neurons that relay signals from sensors in peripheral tissues and (3) by feedback from target cells. Thus, a hormonal signaling axis commonly comprises several components. In mammals and other vertebrates, several hormonal axes are known, such as the hypothalamic-pituitary-gonad axis or the hypothalamic-pituitary-thyroid axis that regulate reproduction and metabolism, respectively. It has been proposed that the basic organization of such hormonal axes is evolutionarily old and that cellular homologs of the hypothalamic-pituitary system can be found for instance in insects. To obtain an appreciation of the similarities between insect and vertebrate neurosecretory axes, we review the organization of neurosecretory cell systems in Drosophila. Our review outlines the major peptidergic hormonal pathways known in Drosophila and presents a set of schemes of hormonal axes and orchestrating peptidergic systems. The detailed organization of the larval and adult Drosophila neurosecretory systems displays only very basic similarities to those in other arthropods and vertebrates.
Competing interplay between systemic and periodontal inflammation: obesity overrides the impact of oral periphery
Authors: Meisel Peter , Pink Christiane , Pitchika Vinay , Nauck Matthias , Völzke Henry , Kocher Thomas
Published: August 2020

Objectives

We aimed at investigating whether the interaction between the local inflammation, periodontitis, and obesity is independently associated with systemic inflammation.

Methods

From the population-based Study of Health in Pomerania, 3366 participants, without (2366) and with (1000) obesity, were studied for the association of periodontitis, measured as probing depth (PD) and plaque together with body mass index (BMI) on C-reactive protein (CRP). Quantile regression was used to evaluate the association between periodontal, anthropometric, and inflammatory variables (outcomes).

Results

The overall prevalence of obesity in this adult population was 31.4% in men and 28.1% in women. Both PD and plaque were positively associated with CRP, revealing an increasing impact across the CRP concentration distribution. Adjusting the regression of CRP or fibrinogen on PD for waist circumference attenuated but did not abolish the PD coefficients. Dental plaque was similarly associated with these interrelations. Association between PD and a dental plaque was different among participants with low-, medium-, or high-risk CRP concentrations.

Conclusion

Local and systemic sources of inflammation contribute to blood levels of inflammatory markers. The respective contributions depend on the relative rate in each of the inflammation-inducing risks and are dominated by adiposity.

Clinical relevance

Keeping systemic inflammation low in order to prevent age-related disease sequelae.
Fractal dimension in CBCT images as predictor for MRONJ: a retrospective cohort study
Authors: Bachtler R. , Walter Ch. , Schulze Ralf K. W.
Published: August 2020

Objective

To estimate boxcounting fractal dimension in a standardized approach in CBCT images of the mandible and maxilla in a group of patients with MRONJ in comparison to a healthy control group.

Material and methods

From our records, a study group consisting of 80 maxillary and mandibular CBCTs in 77 cases of patients having MRONJ was collected. The control group consisted of 84 mandibular and maxillary CBCTs in a total of 78 patients. Using the boxcounting method, fractal dimension (FD) was estimated in a standardized fashion either cranially to the apex of the canine (maxilla) or beneath the tooth apices of the lower molars in the bone area above the mandibular canal (mandible). Intra-observer reproducibility of the FD-measurements was assessed by 6 repeated measurements in 10 individuals. FD values were correlated to age and sex of the individuals as well as to region of interest (ROI) sizes.

Results

FD in the study group (1.684 ± 0.051) was roughly 3.5 % lower than in the control group (1.745 ± 0.026, p < 0.0001). Sex and age had a significant (p < 0.001) influence on FD values in the study group, yet not in the control group. FD values increased with age (study group, spearman-rho: 0.2895, p < 0.05) and also ROI size (both groups, p < 0.0001). Reproducibility was good (intra-class correlation coefficient (ICC): 0.87).

Conclusions

Fractal dimension as assessed by boxcounting seems to be a good descriptor for MRONJ in jaw bones. Influence of age and sex on the outcome values needs to be further investigated in future studies.

Clinical relevance

CBCTs could be assessed with respect to FD to obtain an overview of the disease status of MRONJ patients.
WR-3 Band Waveguide Filter Tolerance Analysis and Surface Metallization Comparison
Authors: Miek Daniel , Kamrath Fynn , Boe Patrick , Höft Michael
Published: August 2020

In this paper, a fifth-order WR-3 band waveguide filter with two transmission zeros (TZs) is presented. The design process is described and manufacturing issues are addressed. The filter is designed to fulfill a center frequency of 237.9 GHz and a fractional bandwidth of 2.64%. Three identical filters are manufactured with the classical computerized numerical control (CNC) milling technique in order to obtain information about the manufacturing repeatability for filter structures in the WR-3 band. The comparison shows that even in very high frequency regions a good repeatability can be achieved, if modern high-speed cutting (HSC) CNC milling machines are used. A comprehensive tolerance analysis is accomplished to classify the obtained results. The filters were manufactured from brass to ensure a meaningful comparability and due to the good machining qualities in CNC machines. In order to reduce the losses, the filters are afterwards sputtered with different materials (gold, silver, copper) to evaluate the effect on the insertion loss at very high frequencies. In comparison with the literature, it is shown that even narrow-band filters, which show a high sensitivity to machining tolerances, can be manufactured with high reliability and manufacturing repeatability in modern CNC milling machines. One of the measured filters shows a return loss higher than 20 dB over the whole passband.
Immune Alterations in a Patient with SARS-CoV-2-Related Acute Respiratory Distress Syndrome
Authors: Bouadma Lila , Wiedemann Aurélie , Patrier Juliette , Surénaud Mathieu , Wicky Paul-Henri , Foucat Emile , Diehl Jean-Luc , Hejblum Boris P. , Sinnah Fabrice , de Montmollin Etienne , Lacabaratz Christine , Thiébaut Rodolphe , Timsit J. F. , Lévy Yves
Published: August 2020

We report a longitudinal analysis of the immune response associated with a fatal case of COVID-19 in Europe. This patient exhibited a rapid evolution towards multiorgan failure. SARS-CoV-2 was detected in multiple nasopharyngeal, blood, and pleural samples, despite antiviral and immunomodulator treatment. Clinical evolution in the blood was marked by an increase (2–3-fold) in differentiated effector T cells expressing exhaustion (PD-1) and senescence (CD57) markers, an expansion of antibody-secreting cells, a 15-fold increase in γδ T cell and proliferating NK-cell populations, and the total disappearance of monocytes, suggesting lung trafficking. In the serum, waves of a pro-inflammatory cytokine storm, Th1 and Th2 activation, and markers of T cell exhaustion, apoptosis, cell cytotoxicity, and endothelial activation were observed until the fatal outcome. This case underscores the need for well-designed studies to investigate complementary approaches to control viral replication, the source of the hyperinflammatory status, and immunomodulation to target the pathophysiological response. The investigation was conducted as part of an overall French clinical cohort assessing patients with COVID-19 and registered in clinicaltrials.gov under the following number: NCT04262921.
Optimizing Predictive Performance of Bayesian Forecasting for Vancomycin Concentration in Intensive Care Patients
Authors: Guo Tingjie , van Hest Reinier M. , Zwep Laura B. , Roggeveen Luca F. , Fleuren Lucas M. , Bosman Rob J. , van der Voort Peter H. J. , Girbes Armand R. J. , Mathot Ron A. A. , Elbers Paul W. G. , van Hasselt Johan G. C.
Published: August 2020

Purpose

Bayesian forecasting is crucial for model-based dose optimization based on therapeutic drug monitoring (TDM) data of vancomycin in intensive care (ICU) patients. We aimed to evaluate the performance of Bayesian forecasting using maximum a posteriori (MAP) estimation for model-based TDM.

Methods

We used a vancomycin TDM data set (n = 408 patients). We compared standard MAP-based Bayesian forecasting with two alternative approaches: (i) adaptive MAP which handles data over multiple iterations, and (ii) weighted MAP which weights the likelihood contribution of data. We evaluated the percentage error (PE) for seven scenarios including historical TDM data from the preceding day up to seven days.

Results

The mean of median PEs of all scenarios for the standard MAP, adaptive MAP and weighted MAP method were − 7.7%, −4.5% and − 6.7%. The adaptive MAP also showed the narrowest inter-quartile range of PE. In addition, regardless of MAP method, including historical TDM data further in the past will increase prediction errors.

Conclusions

The proposed adaptive MAP method outperforms standard MAP in predictive performance and may be considered for improvement of model-based dose optimization. The inclusion of historical data beyond either one day (standard MAP and weighted MAP) or two days (adaptive MAP) reduces predictive performance.
Identification of species traits enhancing yield in wheat-faba bean intercropping: development and sensitivity analysis of a minimalist mixture model
Authors: Berghuijs H. N. C. , Wang Z. , Stomph T. J. , Weih M. , Van der Werf W. , Vico G.
Published: August 2020

Aim

Cereal-legume intercropping can result in yield gains compared to monocrops. We aim to identify the combination of crop traits and management practices that confer a yield advantage in strip intercropping.

Methods

We developed a novel, parameter-sparse process-based crop growth model (Minimalist Mixture Model, M3) that can simulate strip intercrops under well-watered but nitrogen limited growth conditions. It was calibrated and validated for spring wheat (Triticum aestivum) and spring faba bean (Vicia faba) grown as monocrops and intercrops, and used to identify the most suitable trait combinations in these intercrops via sensitivity analyses.

Results

The land equivalent ratio of intercrops was greater than one over a wide range of nitrogen fertilizer levels, but transgressive overyielding, with total yield in the intercrop greater than that of either sole crop, was only obtained at intermediate nitrogen applications. We ranked the local sensitivities of the individual yields of wheat and faba bean of the whole intercrop under various nitrogen input levels to various crop traits.

Conclusions

The total intercrop yield can be improved by selecting specific traits related to phenology of both species, as well as light use efficiency of faba bean and, under high nitrogen applications, of wheat. Changes in height-related crop traits affected individual yields of species in intercrops but not the total intercrop yield.
Representing crop rotations in life cycle assessment: a review of legume LCA studies
Authors: Costa Marcela Porto , Chadwick David , Saget Sophie , Rees Robert M. , Williams Michael , Styles David
Published: August 2020

Purpose

There is an imperative to accurately assess the environmental sustainability of crop system interventions in the context of food security and climate change. Previous studies have indicated that the incorporation of legumes into cereal rotations could reduce overall environmental burdens from cropping systems. However, most life cycle assessment (LCA) studies focus on individual crops and miss environmental consequences of inter-annual crop sequence and nutrient cycling effects. This review investigates state-of-the-art representation of inter-crop rotation effects within legume LCA studies.

Methods

A literature review was undertaken, starting with a search for all peer-reviewed articles with combinations of ‘LCA’, ‘legumes’ and ‘rotations’ or synonyms thereof. In total, 3180 articles were obtained. Articles were screened for compliance with all of the following requirements: (i) reporting results based on LCA or life cycle inventory methodology; (ii) inclusion of (a) legume(s); (iii) the legume(s) is/are analysed within the context of a wider cropping system (i.e. rotation or intercropping). Seventy articles satisfying these requirements were analysed.

Results and discussion

We identified three broad approaches to legume LCA. Most studies involved simple attributional LCA disregarding important interactions across years and crops in rotations. N-fertilizer reduction through legume residue N carryover is either disregarded or the benefit is attributed to the following crop in such studies, whilst N leaching burdens from residues are usually attributed to the legume crop. Some studies applied robust allocation approaches and/or complex functional units to enable analysis of entire rotation sequences, accounting for nutrient cycling and break crop effects. Finally, a few studies applied consequential LCA to identify downstream substitution effects, though these studies did not simultaneously account for agronomic effects of rotational sequence changes.

Conclusions

We recommend that LCA studies for legume cropping systems should (i) evaluate entire rotations; (ii) represent nitrogen and ideally carbon cycling; (iii) for attributional studies, define at least two functional units, where one should encompass the multifunctional outputs of an entire rotation and the other should enable product footprints to be calculated; (iv) for CLCA studies, account for both agronomic changes in rotations and markets effects; (v) include impact categories that reflect hotspots for agricultural production.
Gut Microbiota and Dysbiosis in Alzheimer’s Disease: Implications for Pathogenesis and Treatment
Authors: Liu Shan , Gao Jiguo , Zhu Mingqin , Liu Kangding , Zhang Hong-Liang
Published: August 2020

Understanding how gut flora influences gut-brain communications has been the subject of significant research over the past decade. The broadening of the term “microbiota-gut-brain axis” from “gut-brain axis” underscores a bidirectional communication system between the gut and the brain. The microbiota-gut-brain axis involves metabolic, endocrine, neural, and immune pathways which are crucial for the maintenance of brain homeostasis. Alterations in the composition of gut microbiota are associated with multiple neuropsychiatric disorders. Although a causal relationship between gut dysbiosis and neural dysfunction remains elusive, emerging evidence indicates that gut dysbiosis may promote amyloid-beta aggregation, neuroinflammation, oxidative stress, and insulin resistance in the pathogenesis of Alzheimer’s disease (AD). Illustration of the mechanisms underlying the regulation by gut microbiota may pave the way for developing novel therapeutic strategies for AD. In this narrative review, we provide an overview of gut microbiota and their dysregulation in the pathogenesis of AD. Novel insights into the modification of gut microbiota composition as a preventive or therapeutic approach for AD are highlighted.
Peer Support Groups for Weight Loss
Authors: Ufholz Kelsey
Published: August 2020

Purpose of Review

Social support, especially from peers, has been found to contribute to successful weight loss and long-term weight loss maintenance. Peer support groups may represent a particularly effective intervention technique for weight loss. This review focuses upon peer support weight loss interventions with the objective of identifying common elements of successful programs.

Recent Findings

Peer support interventions often consist of expert-led educational content, supplemented by peer-led activities or discussion. Peer groups may provide support to individuals who have little social support in their normal lives. Interventions are often designed for pre-existing groups, especially high-risk groups such as women from ethnic minorities. Men are underrepresented in weight loss programs and often perceive “dieting” as feminine. However, several peer programs for male sports fans have successfully resulted in weight loss and fostering support for healthy lifestyle among male peers. In addition to professionally created peer support groups, many online weight loss communities are created and moderated by peers. Online communities allow participants to share peer support similar to in-person formats.

Many peer support interventions show significant short-term weight loss. Group members frequently report that peer support was critical to their weight loss success. A sense of community among likeminded individuals with similar goals was frequently cited. Online peer support groups are becoming increasingly prevalent, may fulfill similar needs to in-person groups, and have additional advantages in accessibility, and access to a larger peer network, and may facilitate long-term adherence.
Self-assembly of highly ordered DNA origami lattices at solid-liquid interfaces by controlling cation binding and exchange
Authors: Xin Yang , Martinez Rivadeneira Salvador , Grundmeier Guido , Castro Mario , Keller Adrian
Published: August 2020

The surface-assisted hierarchical self-assembly of DNA origami lattices represents a versatile and straightforward method for the organization of functional nanoscale objects such as proteins and nanoparticles. Here, we demonstrate that controlling the binding and exchange of different monovalent and divalent cation species at the DNA-mica interface enables the self-assembly of highly ordered DNA origami lattices on mica surfaces. The development of lattice quality and order is quantified by a detailed topological analysis of high-speed atomic force microscopy (HS-AFM) images. We find that lattice formation and quality strongly depend on the monovalent cation species. Na+ is more effective than Li+ and K+ in facilitating the assembly of high-quality DNA origami lattices, because it is replacing the divalent cations at their binding sites in the DNA backbone more efficiently. With regard to divalent cations, Ca2+ can be displaced more easily from the backbone phosphates than Mg2+ and is thus superior in guiding lattice assembly. By independently adjusting incubation time, DNA origami concentration, and cation species, we thus obtain a highly ordered DNA origami lattice with an unprecedented normalized correlation length of 8.2. Beyond the correlation length, we use computer vision algorithms to compute the time course of different topological observables that, overall, demonstrate that replacing MgCl2 by CaCl2 enables the synthesis of DNA origami lattices with drastically increased lattice order.
Winner takes all: reconstructing the decapitation of a warrior in Bronze Age China from osteological evidence
Authors: Zhou Yawei , Lin Shuang , Qin Rangping , Yeh Hui-Yuan , Zhang Qun
Published: August 2020

Decapitation is an ancient practice in Asia with inadequate research. The present study reports on the osteological examination of a headless skeleton excavated from a high-status tomb in Chu State style dating back to the late Warring States Period (ca. 3th century BC) in Lu’an, Anhui, China. The individual is identified as a victim of decapitation with five peri-mortem sharp force cut marks on the posterior parts of the cervical vertebrae, and another one on the right second metacarpal. Microscopic observation of the kerfs, the historical records and archaeological evidence support the speculation that the individual could be a warrior of Chu State, who is decapitated after being wounded during the war against the Qin State. The hacking implement and the sequences of the cut marks are further discussed to reconstruct the process of execution. This multidisciplinary reconstruction is the first scientific osteological analysis of the decapitation on the human remains from the Chinese Bronze Age. Moreover, it will enrich our knowledge of the decapitation phenomenon in terms of war and execution in ancient China.
Exploring the Orthogonal Relationship between Controlled and Automated Processes in Skilled Action
Authors: Toner John , Moran Aidan
Published: August 2020

Traditional models of skill learning posit that skilled action unfolds in an automatic manner and that control will prove deleterious to movement and performance proficiency. These perspectives assume that automated processes are characterised by low levels of control and vice versa. By contrast, a number of authors have recently put forward hybrid theories of skilled action which have sought to capture the close integration between fine-grained automatic motor routines and intentional states. Drawing heavily on the work of Bebko et al. (2005) and Christensen et al. (2016), we argue that controlled and automated processes must operate in parallel if skilled performers are to address the wide range of challenges that they are faced with in training and competition. More specifically, we show how skilled performers use controlled processes to update and improve motor execution in training contexts and to stabilise performance under pressurised conditions.
The African citrus triozid Trioza erytreae Del Guercio (Hemiptera: Triozidae): temporal dynamics and susceptibility to entomopathogenic fungi in East Africa
Authors: Aidoo Owusu Fordjour , Tanga C. M. , Mohamed S. A. , Khamis F. M. , Opisa S. , Rasowo B. A. , Kimemia J. W. , Ambajo J. , Sétamou M. , Ekesi S. , Borgemeister C.
Published: August 2020

The African citrus triozid Trioza erytreae Del Guercio (Hemiptera: Triozidae) is the most destructive citrus pest. Presently, biological data on T. erytreae are insufficient for important parameters like distribution, seasonal dynamics and entomopathogens. Therefore, we determined the temporal dynamics of T. erytreae along three different altitudinal gradients in Kenya. In low altitudes, females of T. erytreae reactivated and started laying eggs between late February and early March. The mean monthly number of immature stages of T. erytreae per flush shoot peaked in February, whereas adults peaked in March. For mid-altitudes, T. erytreae mean populations peaked in February, but adults were already present in December. In high altitudes, adults appeared in June, and females began laying eggs. Trioza erytreae population densities in shaded trees positively and significantly correlated with unshaded trees. There was a significant difference between adult density and maximum temperature, average temperature, solar radiation, evaporation and dew point. Furthermore, this study evaluated the effects of 11 Metarhizium anisopliae and 4 Beauveria bassiana fungal isolates against adult T. erytreae under laboratory conditions. Metarhizium anisopliae ICIPE 18 and ICIPE 69 were the most potent isolates, causing 97.5% and 82.5% mortalities within the shortest LT50 time of 4.4 and 5.9 days, respectively. The presence of Diaphorina citri Kuwayama (Hemiptera: Liviidae) on Zanthozylum capense requires further investigation. Our findings provide relevant information for early detection, monitoring and developing biopesticides against the pest.
Developmental trajectories of the socioeconomic status of occupational aspirations during adolescence
Authors: Miyamoto Ai , Wicht Alexandra
Published: August 2020

Introduction

Prominent theories of career development suggest age‐related changes in adolescents' occupational aspirations. However, little is known about how exactly and to what extent, adolescents' aspirations change, particularly regarding the socioeconomic status (SES) of aspired occupations. We aim at extending our knowledge of the developmental trajectories of the SES of occupational aspirations and potential gender differences in those trajectories.

Methods

We used longitudinal data from the German National Educational Panel Study (NEPS) consisting of a large and representative sample of secondary school students (N = 5,964, 50% females) from Grades 8 to 10 (age 14–16). Data were collected via a paper and pencil survey which was carried out in classrooms.

Results

Our analysis of a latent growth curve model revealed that adolescents experienced small increases in the SES of occupational aspirations from Grades 8 to 10. Multi‐group models reveal that females initially aspired to higher‐SES occupations and their aspirations exhibited larger growth over time compared to males.

Conclusions

Our findings are in line with those from other countries but not with all, indicating some cross‐cultural variabilities. Within cultures, the developmental trajectories of the SES of occupational aspirations seem to be similar across age‐cohorts in the last 30 years. Despite women aspire to higher‐SES occupations during adolescence, they often obtain lower‐SES occupations than men in adulthood. Future research is needed to better understand the link between gender differences in the SES of occupational aspirations in adolescence and gender differences in the SES of occupational attainment in adulthood.
Non‐suicidal self‐injury in adolescence: Longitudinal evidence of recursive associations with adolescent depression and parental rejection
Authors: Zhu Jianjun , Chen Yuanyuan , Su Binyuan
Published: August 2020

Introduction

Non‐suicidal self‐injury (NSSI) has been acknowledged as a major public health concern among adolescents. However, the complex association between parental rejection and NSSI is not entirely understood and the existing literature does not address the underlying mechanism of adolescent depressive symptoms in explaining the process.

Methods

Three waves of data (called T1, T2 and T3) were collected 6 months apart, between November 2018 and 2019, in a sample of 1987 Chinese adolescents (56.1% males; ages 10 to 14, M = 12.32, SD = 0.53). Two separate autoregressive cross‐lagged models were used to examine the bidirectional association between parental rejection and NSSI as well as the role of depressive symptoms in bidirectional mediation.

Results

There was strong evidence of bidirectional effects between parental rejection and NSSI at both 6‐month intervals. Parental rejection at T1/T2 positively predicted NSSI at T2/T3, and, vice versa, NSSI at T1/T2 positively predicted parental rejection at T2/T3. Furthermore, we found that the reciprocal association between parent rejection and NSSI was mediated by adolescent depressive symptoms.

Conclusions

The present study found reciprocal associations between parental rejection and NSSI, and further demonstrated that the bidirectional process was mediated by depressive symptoms. The findings from this study are of great interest as they help to inform the development of future prevention and intervention strategies for NSSI.
The corporate heritage brand paradox: Managing the tension between continuity and change in luxury brands
Authors: Cooper Holly , Merrilees Bill , Miller Dale
Published: August 2020

Corporate heritage brands embrace the seemingly contradictory concepts of continuity and change. This tension between constancy and change represents a core paradox. Brand management must maintain the allure and magic of a corporate brand while concurrently being relevant. Scholars suggests that paradoxes ‘require resolution’ if a corporate brand is to be successful. Yet, how brand management can strategically manage conflicting brand elements remains convoluted. Thus, through qualitative enquiry, we examine the management of heritage brand paradox in the context of luxury corporate heritage brands. The three cases Paspaley, the Huka Lodge and Percy Marks, offer evidence supporting the resolution of brand paradox through strategic brand management. The study provides insight into how management can remain true to the brand’s authentic core and innovatively extend the brand’s heritage, developing a three-part strategic luxury brand-heritage management framework. The framework enhances understanding of the paradox between brand heritage and innovation, as well as resolving the paradox. Additionally, the study develops three specific brand guidelines for managing the brand paradox. Our principal contribution is demonstrating how corporate heritage brands, in the luxury category, change but appear to stay the same - how to remain constant yet relevant.
Active (Evolving) Phase of Equatorial Plasma Bubbles Observed Over Tirunelveli
Authors: Kakad B. , Gurram P. , Bhattacharyya A. , Prasad D. S. V. V. D.
Published: August 2020

Usual post‐sunset generation of equatorial spread F (ESF) irregularities on quiet days (Q‐days) and midnight or post‐midnight generation of ESF on magnetically disturbed days (D‐days) is widely known. However, the duration of evolving or active phase of these freshly generated ESF (FESF) irregularities is not clearly understood. Here, the active phase duration refers to the time period during which the perturbation electric field associated with equatorial plasma bubbles drifting over Tirunelveli is alive. Recently, Gurram et al. (2018) quantified the active phase duration of FESF for both Q‐days and D‐days. It was the first exercise to obtain the average active phase duration of FESF from observations. In view of this, we carried out detailed analysis to examine their dependence on solar flux and geomagnetic activity using long‐term amplitude scintillation observations on 251‐MHz signal. It is found that percentage of days with longer active phase (td≥ 50 min) is higher on D‐days, and it is consistent for all levels of solar flux. Average duration of the active phase of FESF, ⟨td⟩, is 57.9 ± 52.3 min on D‐days and 33.8 ± 23.4 min on Q‐days. The active phase of FESF has tendency to sustain for longer time during low solar flux, which is attributed to presence of weaker ambient ionospheric electric field during that period. It is noted that FESF generated on days with stronger geomagnetic activity tend to have longer active phase. Also, days with FESF cause more moderate–strong scintillations as compared to days with drifted‐in ESF.
This Week: Mud, Monterey Canyon, and Kanye West
Authors:   AGU
Published: August 2020

What Earth and space science stories are we recommending this week?
Reservoir Construction Has Reduced Organic Carbon Deposition in the East China Sea by Half Since 2006
Authors: Wang Chenglong , Hao Zhe , Gao Jianhua , Feng Ziyue , Ding Yongcheng , Zhang Chuchu , Zou Xinqing
Published: August 2020

River‐dominated marginal seas are important carbon sinks on Earth. However, their carbon sequestration capacities are changing due to increased anthropogenic perturbations. Herein, we employ substantial datasets to study the characteristics of organic carbon (OC) from the East China Sea (ECS) in 2006 and 2018 and reveal the impacts of reservoir construction on the OC deposition in this region. We show that the distribution of sedimentary OC in the ECS is primarily controlled by riverine input and seabed erosion processes. Hydrodynamic processes influence the OC deposition due to both the scouring of fine‐grained sediments and selective degradation of OC associated with the sediment mobilization. The deposition flux of OC in the ECS decreased by 48% after reservoir construction. These findings demonstrate that reservoir construction seriously affected the OC deposition in the ECS and may be applicable to river‐dominated continental shelves worldwide.
Cascading Toward a Kilometer‐Scale GCM: Impacts of a Scale‐Aware Convection Parameterization in the Goddard Earth Observing System GCM
Authors: Freitas Saulo R. , Putman William M. , Arnold Nathan P. , Adams David K. , Grell Georg A.
Published: August 2020

The National Aeronautics and Space Administration (NASA) Goddard Earth Observing System global circulation model (GCM) is evaluated through a cascade of simulations with increasing horizontal resolution. This model employs a nonhydrostatic dynamical core and includes a scale‐aware, deep convection parameterization (DPCP). The 40‐day simulations at six resolutions (100 km to 3 km) with unvarying model formulation were produced. At the highest resolution, extreme experiments were carried out: one with no DPCP and one with its scale awareness eliminated. Simulated precipitation, radiative balance, and atmospheric thermodynamic and dynamical variables are well reproduced with respect to both observational and reanalysis data. As model resolution increases, the convective precipitation smoothly transitions from being mostly produced by the convection parameterization to the cloud microphysics parameterization. However, contrary to current thought, these extreme cases argue for maintaining, to some extent, the scale‐aware DPCP even at 3‐km scale, as the run relying solely on explicit grid‐scale production of rainfall performs more poorly at this resolution.