bluuebunny/crossref_metadata_2025 huggingface dataset:
Metabolism and Gut Microbiota in Cancer Immunoediting, CD8/Treg Ratios, Immune Cell Homeostasis, and Cancer (Immuno)Therapy: Concise Review
Authors: Kareva Irina
Published: July 2019

The concept of immunoediting, a process whereby the immune system eliminates immunogenic cancer cell clones, allowing the remaining cells to progress and form a tumor, has evolved with growing appreciation of the importance of cancer ecology on tumor progression. As cancer cells grow and modify their environment, they create spatial and nutrient constraints that may affect not only immune cell function but also differentiation, tipping the balance between cytotoxic and regulatory immunity to facilitate tumor growth. Here, we review how immunometabolism may contribute to cancer escape from the immune system, as well as highlight an emerging role of gut microbiota, its effects on the immune system and on response to immunotherapy. We conclude with a discussion of how these pieces can be integrated to devise better combination therapies and highlight the role of computational approaches as a potential tool to aid in combination therapy design. Stem Cells  2019;37:1273–1280
Optimal tuning of fuzzy parameters for structural motion control using multiverse optimizer
Authors: Azizi Mahdi , Ghasemi Seyyed Arash Mousavi , Ejlali Reza Goli , Talatahari Siamak
Published: July 2019

In recent years, there is an increasing interest in optimization of structural control algorithms. Fuzzy logic controller is one of the most common and versatile control algorithms that is generally formulated based on the human knowledge and expert. Human knowledge and experience do not yield optimal control responses for a given structure, and tuning of the fuzzy parameters is necessary. This paper focuses on the optimization of a fuzzy controller applied to a seismically excited nonlinear building. In the majority of cases, this problem is formulated based on the linear behavior of the structure; however, in this paper, objective functions and the evaluation criteria are considered with respect to the nonlinear responses of the structures. Multiverse optimizer is a novel nature‐inspired optimization algorithm that is based on the three concepts of cosmology as white hole, black hole, and wormhole. This algorithm has fast convergence rate and can be utilized in continuous and discrete optimization problems. In this paper, the multiverse optimizer is considered as the optimization algorithm for optimization of the fuzzy controller. The performance of the selected algorithm is compared with eight different optimization algorithms. The results prove that the selected algorithm is able to provide very competitive results.
Metal Nanoparticles Syntheses on Ionic Liquids Functionalized Mesoporous Silica SBA‐15
Authors: Kusumawati Etty N. , Sasaki Takehiko
Published: July 2019

Supported metal nanoparticles hold great promise in heterogeneous catalysis as active and reusable catalysts for various organic transformations. Preparation methods of metal nanoparticles with excellent control over size, shape, and morphology on supports has significantly advanced to improve the performances of the resulting catalysts. Here, we aim to discuss the development of supported metal nanoparticles on mesoporous silica SBA‐15 in the presence of immobilized ionic liquids mostly based on examples from the previously reported results. This review highlights the preparation methods for size‐controlled syntheses and the immobilization of metal nanoparticles on solid supports, especially SBA‐15 by various techniques.
Study on sensitivity characteristic of capacitive coupler for PD detection in HV cable joint
Authors: Ruan Jiangjun , Tang Liezheng , Chen Rou , Li Tiecheng , Yang Zhifei , Xiong Min , Yi Fan
Published: July 2019

The capacitive coupler is an attractive tool for on‐site partial discharge (PD) detection in a cable joint. To study its sensitivity characteristic, PDs in a 110‐kV prefabricated joint containing two artificial defects were detected successively using capacitive couplers with six different electrode widths installed at the same position of the cable. For the quantification of sensor sensitivity, the sensitivity factor is defined as the ratio of capacitive coupler output voltage amplitude to apparent charge that was determined through a conventional PD‐measuring circuit according to IEC 60270. As random variables, the sensitivity factors were displayed in the probability distribution plots for each capacitive coupler to visually compare their sensitivity levels. The results demonstrate an almost monotonically increasing dependence of sensitivity on the coupling electrode width, which agrees with the qualitative analysis based on the amplitude–frequency characteristic of the capacitive coupler. Besides, there is an obvious distinction in sensitivity factors between two distinct defects, indicating that the capacitive coupler is more suitable for PD trend analysis rather than apparent charge quantification. In addition, the insensitivity of the capacitive coupler to certain defect types may explain the cause of some undetectable dead zones in on‐site PD measurement. This study provides experimental support for the geometrical optimization of capacitive couplers. © 2019 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Fifth Graders’ Understandings of Giftedness
Authors: Barone Diane , Barone Rebecca
Published: July 2019

In this qualitative study, the authors explored the multimodal responses provided by gifted fifth graders. Students read the novelUngiftedby Gordon Korman and responded through writing, drawing, and talking. They preferred plot summaries for their written response and created a new form, visual summary, in which image was dominant. In their conversations, students discussed giftedness and how teachers marginalized them for instruction. Students shared how giftedness, as measured throughIQtesting, is variable and can be changed by the context of instruction. Using a book that explicitly considers giftedness offered students an opportunity to make meaning of the text and make connections to their own experiences centered on giftedness.
Agent‐based models of inflammation in translational systems biology: A decade later
Authors: Vodovotz Yoram , An Gary
Published: July 2019

Agent‐based modeling is a rule‐based, discrete‐event, and spatially explicit computational modeling method that employs computational objects that instantiate the rules and interactions among the individual components (“agents”) of system. Agent‐based modeling is well suited to translating into a computational model the knowledge generated from basic science research, particularly with respect to translating across scales the mechanisms of cellular behavior into aggregated cell population dynamics manifesting at the tissue and organ level. This capacity has made agent‐based modeling an integral method in translational systems biology (TSB), an approach that uses multiscale dynamic computational modeling to explicitly represent disease processes in a clinically relevant fashion. The initial work in the early 2000s using agent‐based models (ABMs) in TSB focused on examining acute inflammation and its intersection with wound healing; the decade since has seen vast growth in both the application of agent‐based modeling to a wide array of disease processes as well as methodological advancements in the use and analysis of ABM. This report presents an update on an earlier review of ABMs in TSB and presents examples of exciting progress in the modeling of various organs and diseases that involve inflammation. This review also describes developments that integrate the use of ABMs with cutting‐edge technologies such as high‐performance computing, machine learning, and artificial intelligence, with a view toward the future integration of these methodologies.

This article is categorized under:

Translational, Genomic, and Systems Medicine > Translational Medicine

Models of Systems Properties and Processes > Mechanistic Models

Models of Systems Properties and Processes > Organ, Tissue, and Physiological Models

Models of Systems Properties and Processes > Organismal Models
Angular analysis of the rare decay $$ {\Lambda}_b\to \Lambda (1520)\left(\to N\overline{K}\right){\ell}^{+}{\ell}^{-} $$
Authors: Descotes-Genon S. , Brunet M. Novoa
Published: July 2019

Abstract

We study the differential decay rate for the rare decay

$$ {\Lambda}_b\to \Lambda (1520)\left(\to N\overline{K}\right){\ell}^{+}{\ell}^{-} $$

Λ
b

→
Λ

1520

→
N

K
¯

ℓ
+

ℓ
−

where ℓ is a light lepton and

$$ N\overline{K}=p{K}^{-} $$

N

K
¯

=
p

K
−

,

$$ n{\overline{K}}^0 $$

n

K
¯

0

, as this decay mode can provide new and complementary constraints on the Wilson coefficients in b → sℓ
+
ℓ
− transitions compared to other modes. We provide a determination of the complete angular distribution, assuming unpolarised Λ
b
baryons and neglecting the lepton mass. The resulting angular observables are expressed in terms of helicity amplitudes involving hadronic form factors within the Standard Model and New Physics models with chirality-flipped operators. We study these observables at low and large Λ recoils, using effective theories to determine relations among the hadronic form factors involved. As there is currently no determination of the form factors available from lattice simulations or light-cone sum rules, we perform a first illustration of the sensitivity of some observables to New Physics contributions using hadronic inputs from quark models.
A μ-τ-philic scalar doublet under Zn flavor symmetry
Authors: Abe Yoshihiko , Toma Takashi , Tsumura Koji
Published: July 2019

Abstract

We propose a minimal model which accommodates the long-standing anomaly of muon magnetic moment based on abelian discrete flavor symmetries. The standard model is extended by scalar doublets charged under a Z

n
lepton flavor symmetry. In these models, a large contribution to the muon magnetic moment can be obtained by the chirality enhancement from new scalar mediated diagrams without conflicting with the flavor symmetry. Thanks to the lepton flavor symmetry, these models automatically forbid lepton flavor violation. The minimal model is based on Z
4 symmetry with only one extra scalar doublet. In this model, we show that the parameter space favored by the muon g − 2 can easily be consistent with experimental constraints and theoretical bounds such as the electroweak precision tests, lepton universality, potential stability condition and triviality bound as well as the LHC direct search mass bound. The new contributions to the muon electric dipole moment and the Higgs decay into γγ can be indirect signals of the model.
Cool baryon and quark matter in holographic QCD
Authors: Ishii Takaaki , Järvinen Matti , Nijs Govert
Published: July 2019

Abstract

We establish a holographic bottom-up model which covers both the baryonic and quark matter phases in cold and dense QCD. This is obtained by including the baryons using simple approximation schemes in the V-QCD model, which also includes the backreaction of the quark matter to the dynamics of pure Yang-Mills. We examine two approaches for homogeneous baryon matter: baryons as a thin layer of noninteracting matter in the holographic bulk, and baryons with a homogeneous bulk gauge field. We find that the second approach exhibits phenomenologically reasonable features. At zero temperature, the vacuum, baryon, and quark matter phases are separated by strongly first order transitions as the chemical potential varies. The equation of state in the baryonic phase is found to be stiff, i.e., the speed of sound clearly exceeds the value c

s

2
= 1/3 of conformal plasmas at high baryon densities.
Optimizing real-world factory flows using aggregated discrete event simulation modelling
Authors: Lidberg Simon , Aslam Tehseen , Pehrsson Leif , Ng Amos H. C.
Published: July 2019

Reacting quickly to changing market demands and new variants by improving and adapting industrial systems is an important business advantage. Changes to systems are costly; especially when those systems are already in place. Resources invested should be targeted so that the results of the improvements are maximized. One method allowing this is the combination of discrete event simulation, aggregated models, multi-objective optimization, and data-mining shown in this article. A real-world optimization case study of an industrial problem is conducted resulting in lowering the storage levels, reducing lead time, and lowering batch sizes, showing the potential of optimizing on the factory level. Furthermore, a base for decision-support is presented, generating clusters from the optimization results. These clusters are then used as targets for a decision tree algorithm, creating rules for reaching different solutions for a decision-maker to choose from. Thereby allowing decisions to be driven by data, and not by intuition.
Real-time task processing method based on edge computing for spinning CPS
Authors: Yin Shiyong , Bao Jinsong , Li Jie , Zhang Jie
Published: July 2019

Spinning production is a typical continuous manufacturing process characterized by high speed and uncertain dynamics. Each manufacturing unit in spinning production produces various real-time tasks, which may affect production efficiency and yarn quality if not processed in time. This paper presents an edge computing-based method that is different from traditional centralized cloud computation because its decentralization characteristics meet the high-speed and high-response requirements of yarn production. Edge computing nodes, real-time tasks, and edge computing resources are defined. A system model is established, and a real-time task processing method is proposed for the edge computing scenario. Experimental results indicate that the proposed real-time task processing method based on edge computing can effectively solve the delay problem of real-time task processing in spinning cyber-physical systems, save bandwidth, and enhance the security of task transmission.
The rheological behavior of a pseudo-oil-based mud formulated with Hura crepitans plant oil as base fluid
Authors: Onuh C. Y. , Dosunmu A. , Anawe P. A. L. , Okoro E. E. , Igwilo K. C. , Ehinmowo A. B.
Published: July 2019

The need to prevent our environment from deterioration caused by toxic waste from drilling mud is a prime objective to the oil and gas industry. The exploration of non-edible plant oil for potential base oil in formulating drilling mud is progressing due to the environmentally friendly nature. This research work involves using a commercial synthetic oil from the oil industry and Hura crepitans oil. This oil samples were used as a base fluid in preparing the mud from which the rheological properties were analyzed. Chemical oil extraction method using soxhlet apparatus was used to extract the oil from H. crepitans seeds; it was then distilled to remove the solvent. The mud samples were formulated with 7 and 9 g concentrations of the viscosifier, and properties were measured at 113 and 158 °F. It was then aged for 16 h at 240 °F, and mud properties were measured before and after hot rolling for comparison. Different rheological models were used to describe the experimental data. The physical properties of the synthetic oil and H. crepitans oil reveal a flash point of 213.8 and 399.2 °F, fire point of 226.4 and 500 °F, viscosity index of 297 and 207, specific gravity/density of 805 and 907, respectively. The mud properties of the synthetic oil-based mud had a better emulsion stability, lower plastic viscosity, higher yield point values, and lower gel strength than the H. crepitans oil-based mud. The rheological properties of synthetic and H. crepitans oil-based mud increase and decrease, respectively, after hot rolling. The optimal concentration of viscosifier was 7 g to have maintained the API acceptable range for the rheological properties. Based on the $$R^{2}$$R2 values, RMSE values, and the fitted plots, Herschel–Bulkley had a better description of the experimental data.
An investigation on the effects of silica and copper oxide nanoparticles on rheological and fluid loss property of drilling fluids
Authors: Medhi Srawanti , Chowdhury Satyajit , Gupta Dharmender Kumar , Mazumdar Aryab
Published: July 2019

The increase in hydrocarbon production from problematic production zones having high fluid loss and formation damage has led to the emergence of non-damaging drilling fluids (NDDF). Recently, nanotechnology has found a wide array of applications in the oil and gas industry. Most applications of nanotechnology and enhancement in properties of drilling fluids are restricted to bentonite, xanthan gum and a few oil-based mud. In this study, the effects of silica and copper oxide nanoparticles on polyamine-based NDDF and conventional bentonite-based drilling fluids (BDF) were investigated. Silica nanoparticles were prepared using sol–gel method, and copper oxide nanoparticles were synthesized using co-precipitation method. Nano-based drilling fluids were prepared by dispersing nanoparticles in concentrations of 0.5%, 0.8% and 1% by weight. Furthermore, testing of these nano-based drilling fluids was conducted by measuring specific gravity, pH, rheological properties and filtrate loss at surface temperature (room temperature) and then aging it at bottom-hole temperature (80 °C). The addition of silica and copper oxide nanoparticles to both the drilling fluids did not show much effect on pH and specific gravity. Addition of 0.5% concentration of silica nanoparticles in NDDF showed least degradation in rheological properties compared to other fluids. It showed reduction in filtrate loss by 31%. Moreover, silica nanoparticles in conjunction with BDF acted as a mud thinner showing a decrease in viscosity and yield point. On the contrary, when used with NDDFs, silica nanoparticles acted as a mud thickener. Copper oxide nanoparticles behaved as a thinner in both the drilling fluids with a highest reduction in plastic viscosity of 24% for 0.8% of copper oxide nanoparticle in BDF. Thinning properties were enhanced as the doping concentrations of copper oxide nanoparticles increased; however, the fluid loss controlling ability decreased except for 0.5% concentration by 31% and 24% when used with both the drilling fluids. Additionally, optimal Herschel–Bulkley parameters have been determined by using genetic algorithm to minimize the function of sum of squared errors between observed values and model equation.
Performance of the injection of different gases for enhanced oil recovery in a compositionally grading oil reservoir
Authors: Pourhadi Sajad , Hashemi Fath Aref
Published: July 2019

Reservoir fluid characterization is one of the most important steps in hydrocarbon reservoir engineering calculations and studies. The reservoir fluid composition is not constant along the entire hydrocarbon column and varies along the vertical and horizontal directions. In most cases, such variations have been observed along the vertical direction. This is known as compositional grading phenomenon and has a strong impact on the calculation of original hydrocarbon in place, reservoir development, and oil recovery factor. In this paper, a simulation study was carried out to investigate the effects of compositional grading on reservoir fluid properties and the injection of various gases such as carbon dioxide (CO2), nitrogen (N2), associated petroleum gas (APG), N2–CO2mixture, and water-alternating-CO2injection into different depths of a conventional black oil reservoir in the southwest of Iran in order to detect the best injection depth and achieve the highest oil recovery factor. Due to increase in minimum miscibility pressure (MMP) with depth in compositionally grading reservoirs, MMP variations with depth is one of the main challenges in determining the optimal gas injection depth in such reservoirs. The results showed that N2, APG and N2–CO2mixture were immiscibly injected into all depths of the reservoir due to their high miscibility pressures. The occurrence of gas override and channelling phenomena during the course of immiscible gas injection significantly reduced oil displacement efficiency. On the other hand, CO2was miscibly injected to all reservoir layers and revealed a higher efficiency in comparison with the injection of N2, APG and N2–CO2mixture. In fact, better miscibility development was observed in upper reservoir parts, as compared to the lower parts. Through completing injection wells at upper reservoir parts and then injecting gas into these parts, one can thus further enhance oil recovery and extend production plateau. Moreover, the results confirmed that water-alternating-CO2injection into all reservoir depths, compared to other gas injection scenarios, was associated with increased macroscopic sweep efficiency as well as enhanced oil recovery factor.
Determination of sharing oil losses using proportional and stratified methods in Krisna field
Authors: Hermawan Yulius Deddy , Kristanto Dedy , Hariyadi  , Wibowo
Published: July 2019

This paper discusses about the oil losses due to emulsion, flash, and mixing oil phenomena that frequently happened in the oil and gas companies. The goals of this work are to calculate the emulsion and vapor correction volumes, shrinkage correction volume of the mixture of two or more crude oils with different densities, and to compare between the common proportional method that usually utilized in petroleum industries and the new proposed stratified method for determining of sharing oil losses. The mixing of crude oils from 7 shippers in Krisna field would be used as a case study, and the equation of API 12.3 was chosen to calculate a shrinkage correction volume. Oils from shippers S1, S2, and S3 were first mixed together in TANK-1 of the 1st station; the mixed oil of TANK-1 was then transported to the next station and stored in the TANK-2 and mixed with other oils from shippers S4 and S5; and finally, the mixed oil of TANK-2 was transported to the final station and stored in the TANK-3 and mixed with other oils from shippers S6 and S7. The proportional method gave almost the same shrinkage correction factor (SCF) for all shippers about 0.20%, while stratified method resulted SCF in between 0.05 and 0.31%. Based on our analysis, more often oil mixes with others its volume would be more decreased. The stratified method is therefore recommended to determine sharing oil losses since it gives a fair result.
Response characteristics of conductance sensor and optimization of control-drive circuit in horizontal pipes
Authors: Li He , Cui Yongqiang , Li Jun , Zhao Fengda , Kong Weihang , Wang Min
Published: July 2019

Oil–water two-phase flow in horizontal oil-producing wells with low velocity and high water cut generally presents the phenomenon that the underlayer shows water flow and the upperlayer presents oil flow or a dispersion of oil in water flow. And existing ring-shaped conductance water cut meter cannot obtain the online and real-time response values corresponding to oil field water conductivity in the calculating water holdup procedure. To tackle this issue, this paper designs a mini-conductance probe array (MCPA). In order to further investigate the ability of the total flow rate of the allowable measurement fluid and the parameters valuing of the water cut in horizontal segregated flow, this paper also analyzes the performance of MCPA with different structure parameters in terms of the spatial sensitivity distribution characteristics. Firstly, the geometry model and mathematical model of MCPA are designed, and the MCPA simulation model is analyzed by using the finite element method. Then, the optimum structure parameter results of the sensors are obtained through analyzing the spatial sensitivity distribution characteristics of MCPA in consideration of different distance between the two electrodes and different inner diameters. Lastly, the MCPA different parameters are developed, and experiments are carried out in horizontal multiphase flow experiment facility to analyze spatial sensitivity distribution characteristics of MCPA with different inner diameters on the basis of optimum parameters. Experimental results demonstrated that MCPA with a larger inner diameter would have high measurement accuracy in variation range of water cut, and has a high adaptability in horizontal oil-producing wells with relatively high flow rate and different flow conditions.
Removal Efficiency of Basic Blue 41 by Three Zeolites Prepared from Natural Jordanian Kaolin
Authors: Gougazeh Mousa , Kooli Fethi , Buhl J.-Ch.
Published: July 2019

The conventional method of zeolite synthesis involves an expensive hydrothermal step whereby a mixture of a metakaolinite, sodium hydroxide, and water is preactivated by thermal treatment between 400°C and 1000°C. The objective of the current study was to determine whether Jordanian kaolinite could be converted to zeolite materials without thermal pre-activation. The alkaline hydrothermal transformation of kaolinite into hydroxysodalite (HS) was achieved, then followed by a reaction with citric acid and solid sodium hydroxide to obtain Zeolite A, or by adding solid Na2SiO3 to prepare zeolite X. These materials were tested for their ability to serve as removal agents for Basic Blue 41 (BB-41) dye from artificially contaminated water, at concentrations ranging from 25 to 1000 mg/L. The maximum removal capacities were estimated using the Langmuir model, with a value of 39 mg/g for hydroxysodalite. Zeolite-X achieved the lowest value (19 mg/g). The feasibility of BB-41 removal was deduced from the Freundlich model for the zeolites studied. The reported low-cost method is proposed as an alternative way to reduce the cost of synthesizing zeolite, and the materials were shown to be potential candidates for the removal of BB-41 dye.
Body image and weight management among Hispanic American adolescents: Differences by sport type
Authors: Reina Anita M. , Monsma Eva V. , Dumas Marcus D. , Gay Jennifer L.
Published: July 2019

Background

Adolescents' body image concerns vary by sex, ages, and participation in different types of sports. Little is known about variability of body image and weight management behaviors by sport type in Hispanic American adolescents. This study examined whether body image distortion and dissatisfaction are associated with weight management behaviors by sex and sport type in Hispanic adolescents.

Methods

A sample of 728 Hispanic participants from the United States (61.6% female, Mage = 12.36 ± 2.35) completed the Stunkard Figural Stimuli, reported weight management behaviors and sport participation. Sports were classified as non‐aesthetic (such as soccer), aesthetic (such as cheerleading), or non‐sport participation. Separate multiple linear regression and multinomial logistic regression models were conducted to test adjusted associations between body image dissatisfaction and distortion, and sport type with weight management behaviors.

Results and conclusions

Participants in non‐aesthetic sports (51.2% male) were more dissatisfied with their body image (want to be bigger; B = −0.17; p = .01) and were 1.5 times more likely to use exercise to lose weight than non‐sport participants. Greater body image dissatisfaction increased the likelihood of weight management behaviors. As year in school increased, participants perceived themselves as smaller than their actual BMI and wanted to be smaller. Hispanic females exhibited similar trends to other ethnicities. However, Hispanic males may have interpreted a desire to be “smaller” as a more lean, muscular physique. Subsequent studies should focus on reasons for weight management, and whether those behaviors are healthy.
THE RESERVE UNCERTAINTIES IN THE CHAIN LADDER MODEL OF MACK REVISITED
Authors: Gisler Alois
Published: July 2019

We revisit the “full picture” of the claims development uncertainty in Mack’s (1993) distribution-free stochastic chain ladder model. We derive the uncertainty estimators in a new and easily understandable way, which is much simpler than the derivation found so far in the literature, and compare them with the well known estimators of Mack and of Merz–Wüthrich.

Our uncertainty estimators of the one-year run-off risks are new and different to the Merz–Wüthrich formulas. But if we approximate our estimators by a first order Taylor expansion, we obtain equivalent but simpler formulas. As regards the ultimate run-off risk, we obtain the same formulas as Mack for single accident years and an equivalent but better interpretable formula for the total over all accident years.
Quasi-normal free-surface impacts, capillary rebounds and application to Faraday walkers
Authors: Galeano-Rios C. A. , Milewski P. A. , Vanden-Broeck J.-M.
Published: July 2019

We present a model for capillary-scale objects that bounce on a fluid bath as they also translate horizontally. The rebounding objects are hydrophobic spheres that impact the interface of a bath of incompressible fluid whose motion is described by linearised quasi-potential flow. Under a quasi-normal impact assumption, we demonstrate that the problem can be decomposed into an axisymmetric impact onto a quiescent bath surface, and the unforced evolution of the surface waves. We obtain a walking model that is free of impact parametrisation and we apply this formulation to model droplets walking on a vibrating bath. We show that this model accurately reproduces experimental reports of bouncing modes, impact phases and time-dependent wave field topography for bouncing and walking droplets. Moreover, we revisit the modelling of horizontal drag during droplet impacts to incorporate the effects of the changes in the pressed area during droplet–surface contacts. Finally, we show that this model captures the recently discovered phenomenon of superwalkers.
Control of oblique-type breakdown in a supersonic boundary layer employing streaks
Authors: Sharma Sushank , Shadloo Mostafa S. , Hadjadj Abdellah , Kloker Markus J.
Published: July 2019

The effectiveness of streak modes in controlling the oblique-type breakdown in a supersonic boundary-layer at Mach 2.0 is investigated using direct numerical simulations. Investigations in the literature have shown the effectiveness of streak modes in delaying the onset of transition dominated by two-dimensional waves, but in oblique breakdown, three-dimensional waves and a strong streak mode dominate the transition process. Paredes et al. (J. Fluid Mech., vol. 831, 2017, pp. 524–553) discussed the possible stabilization of supersonic boundary layers by optimally growing streaks using parabolized stability equations. However, no study has as yet been reported regarding direct nonlinear control of oblique breakdown. This study deals with the effects of large-amplitude decaying streak modes generated by a blowing–suction strip at the wall to control full breakdown in a reference case. Modes with four to five times the fundamental wavenumber are found to be beneficial for controlling the transition. In the first region after the control-mode forcing, the beneficial mean-flow distortion (MFD), generated by inducing the control mode, is solely responsible for hampering the growth of the fundamental-mode. On the whole, the MFD and the three-dimensional part of the control contribute equally towards controlling the oblique breakdown. The results show significant suppression of transition, and substantial improvements have been observed in the levels of the skin-friction coefficient and wall-temperature in comparison to the uncontrolled case. Moreover, refreshing the control using an additional downstream control strip increases the gain. However, the forcing amplitude must be carefully chosen in order not to introduce a generalized inflection point in the spanwise averaged mean flow invoking enhanced disturbance growth.
Field measurement of nonlinear changes to large gravity wave groups
Authors: Tang Tianning , Tromans Peter S. , Adcock Thomas A. A.
Published: July 2019

The dynamics of large gravity waves are known to be modified from the linear model by nonlinear physics. In this paper we analyse Eulerian surface elevation time histories measured from two sites, Lake George (Australia) and the North Sea, to examine how weak nonlinearity has modified the shape of extreme wave groups relative to linear theory. We analyse the asymmetry of the extreme wave groups and find that, on average, the wave in front of an extreme wave is smaller than the wave following it. We also observe a contraction in the envelope width of the wave group relative to linear theory. The departures from linear theory are strongly correlated with the steepness of the underlying sea state and are generally consistent with theoretical expectations, providing strong evidence that such nonlinear phenomena arise in naturally occurring water waves.
Serum cholesterol levels preceding to suicide death in Japanese workers: a nested case-control study
Authors: Chen Sanmei , Mizoue Tetsuya , Hu Huanhuan , Kuwahara Keisuke , Honda Toru , Yamamoto Shuichiro , Nakagawa Tohru , Miyamoto Toshiaki , Okazaki Hiroko , Shimizu Makiko , Murakami Taizo , Eguchi Masafumi , Kochi Takeshi , Yamamoto Makoto , Ogasawara Takayuki , Sasaki Naoko , Uehara Akihiko , Imai Teppei , Nishihara Akiko , Hori Ai , Nagahama Satsue , Tomita Kentaro , Konishi Maki , Kabe Isamu , Dohi Seitaro ,   for the Japan Epidemiology Collaboration on Occupational Health Study Group
Published: July 2019

Objective:

To investigate the association between suicide death and serum cholesterol levels as measured at times close to suicide death.

Methods:

We conducted a nested case-control study of 41 cases of suicide deaths and 205 matched controls with serum total cholesterol (TC) levels till 3 years before suicide death in a large cohort of Japanese workers.

Results:

Individuals in the lowest versus highest tertile/predefined category of TC in a Japanese working population had a three- to four-fold greater risk of suicide death. Each 10 mg/dl decrement of average TC was associated with an 18% increased chance of suicide death (95% confidence interval, 2–35%). Similar results were found for TC levels at each year.

Conclusion:

These results suggest that a low serum TC level in recent past is associated with an increased risk of suicide death.
Short-term impact of sucralose consumption on the metabolic response and gut microbiome of healthy adults
Authors: Thomson Pamela , Santibañez Rodrigo , Aguirre Carolina , Galgani Jose E. , Garrido Daniel
Published: July 2019

Sucralose is an artificial non-nutritive sweetener used in foods aimed to reduce sugar and energy intake. While thought to be inert, the impact of sucralose on metabolic control has shown to be the opposite. The gut microbiome has emerged as a factor shaping metabolic responses after sweetener consumption. We examined the short-term effect of sucralose consumption on glucose homeostasis and gut microbiome of healthy male volunteers. We performed a randomised, double-blind study in thirty-four subjects divided into two groups, one that was administered sucralose capsules (780 mg/d for 7 d; n 17) and a control group receiving placebo (n 17). Before and after the intervention, glycaemic and insulinaemic responses were assessed with a standard oral glucose load (75 g). Insulin resistance was determined using homeostasis model assessment of insulin resistance and Matsuda indexes. The gut microbiome was evaluated before and after the intervention by 16S rRNA sequencing. During the study, body weight remained constant in both groups. Glycaemic control and insulin resistance were not affected during the 7-d period. At the phylum level, gut microbiome was not modified in any group. We classified subjects according to their change in insulinaemia after the intervention, to compare the microbiome of responders and non-responders. Independent of consuming sucralose or placebo, individuals with a higher insulinaemic response after the intervention had lower Bacteroidetes and higher Firmicutes abundances. In conclusion, consumption of high doses of sucralose for 7 d does not alter glycaemic control, insulin resistance, or gut microbiome in healthy individuals. However, it highlights the need to address individual responses to sucralose.
Will farmers fully adapt to monsoonal climate change through technological developments? An analysis of rice and livestock production in Thailand
Authors: Seo S. N.
Published: July 2019

The current paper tackles a critical question in climate change literature of whether farmers will be able to fully adapt to monsoonal climate changes owing to technological developments. Making use of the climate, agricultural and social data of Thailand from 1900 to 2015, this paper estimates a technological change instrumental variable by the growth of the normalized rice yield per hectare of land. The estimation shows that 0.98 of the growth in rice yield can be attributed to technological changes while the rest is accounted for by climate, soils and social factors. In the second stage regressions with the technological change indicator, the paper estimates the normalized numbers of the six most important types of live animals in Thailand: goats, chickens, cattle, sheep, pigs and buffaloes. Over the time period studied, the number of each of these live animals has increased vastly, except for buffaloes. The second-stage regressions show that the growth is largely attributable to technological changes, but monsoonal climate variables such as normalized monsoon precipitation ratio and normalized monsoon temperature are not significant factors. The results indicate that the rate of technological changes is overwhelming the rate of climate change on agriculture in Thailand.
Helminths and microbes within the vertebrate gut – not all studies are created equal
Authors: Cortés Alba , Peachey Laura E. , Jenkins Timothy P. , Scotti Riccardo , Cantacessi Cinzia
Published: July 2019

The multifaceted interactions occurring between gastrointestinal (GI) parasitic helminths and the host gut microbiota are emerging as a key area of study within the broader research domain of host-pathogen relationships. Over the past few years, a wealth of investigations has demonstrated that GI helminths interact with the host gut flora, and that such interactions result in modifications of the host immune and metabolic statuses. Nevertheless, whilst selected changes in gut microbial composition are consistently observed in response to GI helminth infections across several host-parasite systems, research in this area to date is largely characterised by inconsistent findings. These discrepancies are particularly evident when data from studies of GI helminth-microbiota interactions conducted in humans from parasite-endemic regions are compared. In this review, we provide an overview of the main sources of variance that affect investigations on helminth-gut microbiota interactions in humans, and propose a series of methodological approaches that, whilst accounting for the inevitable constraints of fieldwork, are aimed at minimising confounding factors and draw biologically meaningful interpretations from highly variable datasets.
Prevalence of low-grade inflammation in depression: a systematic review and meta-analysis of CRP levels
Authors: Osimo Emanuele Felice , Baxter Luke James , Lewis Glyn , Jones Peter B. , Khandaker Golam M.
Published: July 2019

Background

Peripheral low-grade inflammation in depression is increasingly seen as a therapeutic target. We aimed to establish the prevalence of low-grade inflammation in depression, using different C-reactive protein (CRP) levels, through a systematic literature review and meta-analysis.

Methods

We searched the PubMed database from its inception to July 2018, and selected studies that assessed depression using a validated tool/scale, and allowed the calculation of the proportion of patients with low-grade inflammation (CRP >3 mg/L) or elevated CRP (>1 mg/L).

Results

After quality assessment, 37 studies comprising 13 541 depressed patients and 155 728 controls were included. Based on the meta-analysis of 30 studies, the prevalence of low-grade inflammation (CRP >3 mg/L) in depression was 27% (95% CI 21–34%); this prevalence was not associated with sample source (inpatient, outpatient or population-based), antidepressant treatment, participant age, BMI or ethnicity. Based on the meta-analysis of 17 studies of depression and matched healthy controls, the odds ratio for low-grade inflammation in depression was 1.46 (95% CI 1.22–1.75). The prevalence of elevated CRP (>1 mg/L) in depression was 58% (95% CI 47–69%), and the meta-analytic odds ratio for elevated CRP in depression compared with controls was 1.47 (95% CI 1.18–1.82).

Conclusions

About a quarter of patients with depression show evidence of low-grade inflammation, and over half of patients show mildly elevated CRP levels. There are significant differences in the prevalence of low-grade inflammation between patients and matched healthy controls. These findings suggest that inflammation could be relevant to a large number of patients with depression.
Internalizing and externalizing psychopathology in middle age: genetic and environmental architecture and stability of symptoms over 15 to 20 years
Authors: Gustavson Daniel E. , Franz Carol E. , Panizzon Matthew S. , Lyons Michael J. , Kremen William S.
Published: July 2019

Background

Internalizing and externalizing psychopathology factors explain much of the covariance among psychiatric conditions, especially at the level of genetic risk. However, few studies have examined internalizing and externalizing factors in middle-aged samples, especially their ability to predict later symptoms across midlife. The goals of the current study were (i) to quantify the genetic and environmental influences on internalizing and externalizing psychopathology in individuals in their early 40s, and (ii) examine the extent to which these genetic and environmental influences predict self-reported measures of internalizing and externalizing symptoms 15–20 years later.

Method

1484 male twins completed diagnostic interviews of psychopathology at mean age 41 and self-reported measures of anxiety, depression, substance use, and related variables at up to two time-points in late middle age (mean ages 56 and 62).

Results

Structural equation modeling of the diagnostic interviews confirmed that internalizing and externalizing factors accounted for most of the genetic variance in individual disorders, with substantial genetic (ra = 0.70) and environmental (re = 0.77) correlations between the factors. Internalizing psychopathology at age 41 was correlated with latent factors capturing anxiety, depression, and/or post-traumatic stress symptoms at ages 56 (r = 0.51) and 62 (r = 0.43). Externalizing psychopathology at age 41 was correlated r = 0.67 with a latent factor capturing aggression, tobacco use, and alcohol use at age 56. Stability of both factors was driven by genetic influences.

Conclusions

These findings demonstrate the considerable stability of internalizing and externalizing psychopathology symptoms across middle age, especially their genetic influences. Diagnostic interviews effectively predict self-reported symptoms and behaviors 15–20 years later.
Association of PTSD symptom groups with functional impairment and distress in trauma-exposed disaster survivors
Authors: North Carol S. , Van Enkevort Erin , Hong Barry A. , Surís Alina M.
Published: July 2019

Background

In the nearly a quarter of a century since the addition of the clinically significant distress/impairment criterion to the definition of PTSD in DSM-IV, little research has been done to examine the association of this criterion with symptom group criteria and with the numbing subgroup specifically. This study was conducted to examine these relationships in a large database of disaster survivors consistently studied across 12 different incidents of the full range of disaster typology.

Methods

Analysis was conducted on a merged database representing 1187 trauma-exposed survivors of 12 different disasters studied systematically. DSM-IV-TR criteria for disaster-related PTSD were assessed with the Diagnostic Interview Schedule.

Results

PTSD Group C (avoidance/numbing) and numbing specifically were less common and more associated than other symptom groups with criterion F (distress/impairment). Consistently in multivariable models, group C and numbing were independently associated with criterion F. Group D (hyperarousal) was less strongly associated with criterion F. Neither group B (intrusion) nor avoidance were associated with criterion F.

Conclusions

In this and other studies, group C and numbing specifically have been shown to be associated with criterion F, which is consistent with the demonstration that group C and the numbing component specifically are central to the psychopathology of PTSD. The addition of the distress/impairment requirement broadly across the psychiatric diagnoses in DSM-IV added little value to PTSD symptom criteria. Future revisions of diagnostic criteria may benefit by carefully considering these findings to possibly re-include a prominent numbing symptom section.
Metabolism, bioenergetics and thermal physiology: influences of the human intestinal microbiota
Authors: Armstrong Lawrence E. , Casa Douglas J. , Belval Luke N.
Published: July 2019

The micro-organisms which inhabit the human gut (i.e. the intestinal microbiota) influence numerous human biochemical pathways and physiological functions. The present review focuses on two questions, ‘Are intestinal microbiota effects measurable and meaningful?’ and ‘What research methods and variables are influenced by intestinal microbiota effects?’. These questions are considered with respect to doubly labelled water measurements of energy expenditure, heat balance calculations and models, measurements of RMR via indirect calorimetry, and diet-induced energy expenditure. Several lines of evidence suggest that the intestinal microbiota introduces measurement variability and measurement errors which have been overlooked in research studies involving nutrition, bioenergetics, physiology and temperature regulation. Therefore, we recommend that present conceptual models and research techniques be updated via future experiments, to account for the metabolic processes and regulatory influences of the intestinal microbiota.