bluuebunny/crossref_metadata_2025 huggingface dataset:
Status of the JSME Codification Activities on Tornado-Generated Missile Protection for Structures of Nuclear Power Plants
Authors: Shirai Koji , Beppu Masuhiro , Hirai Hideo , Yamada Kazuhiko , Yoshida Shinichi , Shinohara Yohei
Published: October 2017

In Japan, after the Great East Japan Earthquake, existing nuclear power plants (NPPs) are being re-examined to ensure they can withstand more intense natural phenomena such as earthquakes, tsunamis, volcanic eruptions, forest fires and tornadoes, without any loss of capability to safely maintain their function. One of the representative tornado-generated missiles (tornado missiles) prescribed by the NRA (Nuclear Regular Authority) is 0.2m wide × 0.3m deep × 4.2m long, 135kg in weight with a maximum velocity of 51m/s; a rectangular steel pipe. Several impact design methodologies have been implemented to the safety evaluation during business licensing activities to restart NPPs. However, there is considerable variation among licensees when implementing these impact design methodologies and no clear guidance explaining the requirements necessary to achieve accurate results for the impact design of tornado missiles.

In response, in 2014, the Japan Society of Mechanical Engineers (JSME) formed a Special Task Group (STG) on codification activities for the purpose of developing a guidance document on the impact design of the system, structure and components (SSCs) of the NPPs against tornado missiles. The current guidance undertaken comprises the following five chapters and appendices.

- Section A: This chapter defines the objectives and scope.

- Section B: This chapter outlines the methodology of how to determine the design tornado intensities and design loads against tornado missiles for SSCs.

- Section C: This chapter provides the methodology on how to select representative tornado missile designs from the plant walk-down investigative results and set the design impact velocity based on several vortex models.

- Section D: This chapter notes empirical formulas for the local damage of steel/concrete panels to prevent penetration or scabbing to which tornado missiles are prone. Methods to set design impact loads for hard and soft missiles are also presented, as well as those used to evaluate structural response using an elastic or elastic-plastic single degree of freedom (SDOF) model subjected to impact loads.

- Section E: Modern explicit dynamics finite element computer codes used to design and evaluate SSCs, such as LS-DYNA, AUTODYN, Abaqus/Explicit are sophisticated and robust enough to produce accurate results for tornado missile impact events. This chapter provides guidance on a computational modelling method for explicit dynamics, including the construction of quality finite element models following strain-based acceptance criteria.

- Appendices: as an example of setting tornado missiles and impact velocity, benchmarking of explicit dynamic codes is introduced.

An overview of the contents of this guidance document will be focused on in this paper.
The Preliminary Design of Compacted Heat Exchanger Based on Helical Baffles Technique
Authors: Cong Wang , Jinrong Qiu , Yi Liao
Published: October 2017

This paper conducted a preliminary design of heat exchanger based on helical baffles technique. The realizable k-ε turbulent model was adopted to simulate the flow properties and heat transfer in the shell side with the computational fluid dynamics software. The numerical results show that the helical baffles heat exchanger offer about 11% higher heat transfer coefficient, 6% higher pressure drop and 10% lesser heat exchanger area than of heat exchanger with segmental baffles under the same heat exchanger power. It could help achieve the goal of reducing volume of heat exchanger with helical baffles technique.
Task Analysis in Designing the Control Room of Nuclear Power Plant and Safety Reviewing
Authors: Feng Yan , Li Liang , Liu Jingbin , Qiao Ning , Guo Yinhui
Published: October 2017

Task analysis identifies the specific tasks needed to accomplish human actions, and the information, control and task support required to complete those tasks. In the control room design, the functions allocated to personnel shall be performed analysis, and it is identified that the specific task can be accomplished by the personnel. Task analysis can provide one of the bases for the human system interface design decisions; match human performance requirements with human capabilities; provide input to procedure development and provide input to staffing, training, and communications requirements of the plant. The method about task analysis and the screening methodology used to select the tasks for analysis are very important. Usually, the scope of task analysis is divided into two complementary activities: function-based task analysis and traditional task analysis, or operational sequence analysis. Function-based task analysis is the functional decomposition (goal-means analysis) for normal power operations. The traditional task analysis, or operational sequence analysis is developed for a representative set of operational and maintenance tasks. The operational sequence analysis include OSA-1 and OSA-2.The task analysis considers alerts, such as alarms and warnings, decision-making, response, teamwork and communication, workload task support, workplace factors, situational and performance shaping factors and hazard identification. The paper also describes the selected basis of selecting the operational sequence to be analyzed in the operational sequence analysis. The method about task analysis and the screening methodology used to select the tasks for analysis are very important. The objective of task analysis review is to verify that the applicant undertook analyses identifying the specific tasks needed to accomplish personnel functions, and also the alarms, information, control- and task-support required to complete those duties. The paper mainly describes not only the above content, but also the reviewing work about task analysis and questions found in reviewing. In this article, there are some examples about the function-based task analysis. At last, the verification for task analysis is addressed simply.
Application of Monte Carlo to PWR Cavity Radiation Streaming Calculation
Authors: Jingru Han , Qiaofeng Liu , Haiying Chen , Chunming Zhang
Published: October 2017

The cavity streaming is the neutron beam from the reactor core through the tunnel, which is between the external surface of the pressure vessel and the shield inner surface.

Reactor cavity streaming calculation is a typical deep penetration problem with complex geometry. The accurate calculation of neutron radiation streaming is a key problem to the reactor shielding calculation, for which the Monte Carlo method and the discrete ordinate method are two popular methods. The speed of discrete ordinate method calculation is fast, but it is hard to describe the complex pile of cavity; the Monte Carlo method can accurately describe the complex geometry, it has a high calculation precision, but with a low direct simulation efficiency. Based on a pressurized water reactor nuclear power plant, this paper presents a detailed model realized by Monte Carlo code, with continuous energy points cross section libraries. The neutron flux density distribution of PWR reactor cavity streaming can directly be calculated by a three-dimensional simulation. For such an actual deep penetration problem, a variety of variance reduction techniques are studied, an effective variance reduction technique is used to obtain results with small statistic errors for a Monte Carlo simulation, which effectively solves the problem of large-scale deep penetrating convergence difficulty, the cavity radiation streaming calculation and analysis are completed. The result shows that the Monte Carlo method can be used as a powerful tool to solve the problem of cavity streaming leakage.
Radiation Dose Evaluation of Marine Organisms for Coastal Nuclear Power Plant
Authors: Shaowei Wang
Published: October 2017

Fukushima nuclear accident has aroused concern about ionizing radiation damage to the marine environment. It is subjective to assess the accident’s effects on the marine ecological environment during different scholars, because of different understanding of nuclide release quantity, dose estimation models and parameters. To solve this problem, a gradually progressive research approach is designed based on a coastal nuclear power plant in study, which is “from influencing factors analyzing to biological dose assessment, and to uncertainty analysis”. First, the factors affecting the biological dose assessment will be analyzed, and then the concerns of the various factors and their impact on the results of the assessment will be discussed. Second, the biological dose will be assessed based on appropriate dose mode after selecting representative species and analyzing critical exposure pathway. Finally, the uncertainty of radionuclide release quantity, dilution factor, concentration factor, dose conversion factor will be analyzed. The study will provide reliable scientific bases to identify the factors impact biological dose assessment effectively, and improve the accuracy of the dose evaluation.
Risk Analysis of Spent Fuel Pool Caused by Seismic Events
Authors: Wang Ming , Lin Modi , Wang Jinkai , Yang Chunju
Published: October 2017

Spent fuel pool stores fuel assemblies that have been removed from the reactor in previous years, and the release of radioactive material to the external environment is easier than reactor core after fuel damage occurs. In the earthquake situation, the spent fuel pool itself and its accident corresponding mitigation measures are likely to fail at the same time, causing serious accident consequences. Based on the design and operation characteristics of typical CPR1000 units, this paper uses the probability safety analysis method to quantitatively evaluate the risk of spent fuel pool caused by seismic events, and identify the weak links in the design and operation of CPR1000 units. Quantitative analysis shows that the risk of the spent fuel pool caused by seismic events is relatively low relative to the core, with the main risks coming from the collapse of the fuel building and structural damage to the spent fuel pool. In addition, seismic events affect both the core and spent fuel pool, and the steam and radioactivity of spent fuel pools will have an impact on mitigation of core accidents.
The Root Cause Analysis of the Bolt Fracture in the Nuclear Power Plant Essential Service Water System
Authors: Nan Li , Yi Lao , Yinhui Che
Published: October 2017

When inspecting in the nuclear power plant, the bolt of the 001/004 pump in Essential Service Water system was found fracture. The bolt in 001 pump had ever fractured before, and it had been replaced. In this paper, the material, microstructure, energy dispersive spectrometry and mechanical check calculation of the bolt are analyzed. The result shows, the bolt breakage is for stress corrosion cracking, the corrosion element is Cl−. When the martensitic stainless steel is in the heat treatment, the temperature is improper control, which causing the Cr element distribution changed. So the ability of material to resist corrosion becomes poor which is the root cause of the bolt fracture.
The Removal of Uranium From Simulated Ammonium Diuranate Filtrate by Nanofiltration
Authors: Zhongwei Yuan , Runci Wang , Taihong Yan , Weifang Zheng
Published: October 2017

In this study, a simulated ammonium diuranate filtrate (ADUF) which was obtained by adding uranyl nitrate to a 35 g/L ammonium nitrate solution to adjust the uranium concentration to about 50 mg/L was treated by a nanofiltration process. Experiments were carried out on a plate membrane testing device with a trans-membrane pressure (TMP) range of 0.5 ∼ 3.0 MPa, a crossflow velocity range of 10 ∼ 50 cm/s and a temperature range of 5 ∼ 35 °C. The results show that NF270 membrane has good rejection property for uranium and excellent permeability for ammonium nitrate. The ammonium nitrate concentration in the permeate is about 32 g/L which means the reject ratio of ammonium nitrate is only about 10%. Though NF270 membrane shows good uranium rejection property, the corresponding permeate flux is very high. When the trans-membrane pressure is 1.5 MPa, the uranium reject ratio is 96.8% and the the corresponding permeate flux is about 80 L/(m2·h). It indicates a bright application prospect of nanofiltration process in the treatment of ADUF.
Behavior of Simulated Molten Metal at Channel Modeled Boiling Water Reactors
Authors: Hihara Yutaro , Matsuura Kota , Monji Hideaki , Abe Yutaka , Kaneko Akiko , Yoshida Hiroyuki , Yamashita Susumu
Published: October 2017

When a severe accident occurs, decommissioning work becomes important task. In the decommissioning work after the severe accident, establishing the way to estimate the sedimentation place of molten debris is important. However, the technique to estimate exactly sedimentation place has not been enough. Therefore, the detailed and phenomenological numerical simulation code named JUPITER for predicting the molten core behavior is under development. The comparison between experimental and numerical results is necessary to clarify the validity of the numerical analysis code. This study provides the experimental data for a BWR to examine the numerical simulation code in order to contribute to progress of the decommissioning work.
Development and Application of the Device for Cutting and Disintegration of Radioactive Contamination Glove Box
Authors: Feng Zhang , Weibo Qu , Hong Jiang , Dongmei Yao , Dongqiang Yu , Xiaogang Wan , Chengcheng Xi
Published: October 2017

In the process of decommissioning of the nuclear facilities, abandoned and contaminated equipments or devices often need to be dismantled and cut into proper pieces in order to facilitate subsequent treatment and disposal. Since the nuclear facilities were places where radioactive operations were frequently executed, gloveboxes should be such typical abandoned and contaminated devices. Usually, gloveboxes were cut into proper pieces by kinds of tools which was chosen depending on the thickness of stainless steel from different parts of gloveboxes. This traditional cutting was laborious and high concentration of harmful aerosols and gases would be created during the cutting operation. In order to develop more advanced cutting and disintegration ways, a cutting and disintegration device was developed using abandoned and contaminated gloveboxes as operation objects in this work. During the design of this device, the operation convenience, operation exactitude and the protection for operators were fully considered. Also, the hot verification test was carried out. Based on the verification test results, the cutting and disintegration device was reliable and could meet the design requirements, which precisely executed various movements required in the hot verification test. Due to the application of remote operation and advanced cold cutting as the main cutting way in the development of this cutting and disintegration device, radioactive aerosols and harmful gases created during operation of this device were obviously declined compared to past cutting devices, which was of great importance to the health of operators. This work can provide technical support for the development of other similar devices applied in nuclear facility decommissioning.
Tackling Coolant Freezing in Generation-IV Molten Salt Reactors
Authors: Le Brun N. , Charogiannis A. , Hewitt G. F. , Markides C. N.
Published: October 2017

In this study we describe an experimental system designed to simulate the conditions of transient freezing which can occur in abnormal behaviour of molten salt reactors (MSRs). Freezing of coolant is indeed one of the main technical challenges preventing the deployment of MSR. First a novel experimental technique is presented by which it is possible to accurately track the growth of the solidified layer of fluid near a cold surface in an internal flow of liquid. This scenario simulates the possible solidification of a molten salt coolant over a cold wall inside the piping system of the MSR. Specifically, we conducted measurements using water as a simulant for the molten salt, and liquid nitrogen to achieve high heat removal rate at the wall. Particle image velocimetry and planar induced fluorescence were used as diagnostic techniques to track the growth of the solid layer. In addition this study describes a thermo-hydraulic model which has been used to characterise transient freezing in internal flow and compares the said model with the experiments. The numerical simulations were shown to be able to capture qualitatively and quantitatively all the essential processes involved in internal flow transient freezing. Accurate numerical predictive tools such the one presented in this work are essential in simulating the behaviour of MSR under accident conditions.
Development of Experimental and Computational Procedures for Nuclear Power Plant Component Testing Under Flooding Conditions
Authors: Tahhan Antonio , Muchmore Cody , Nichols Larinda , Wells Alison , Roberts Gregory , Ryan Emerald , Suresh Sneha , Bhandari Bishwo , Pope Chad
Published: October 2017

Idaho State University (ISU), with support from Idaho National Laboratory, is actively engaged in enhancing nuclear power plant risk modeling. The ISU team is significantly increasing the understanding of non-containment, nuclear power plant component performance under flooding conditions. The work involves experimentation activities and development of mathematical models, using data from component flooding experiments. The research consists in developing experimentation procedures that comprised small scale component testing, followed by simple and then complex full scale component testing. The research is taking place in the Component Flooding Evaluation Laboratory (CFEL). Tests in CFEL will include water rise, spray, and wave impact experiments on passive and active components.

Initial development work focused on small scale components, radios and simulated doors, that served as a low-risk and low-cost proof-of-concept options. Following these tests, full-scale component tests were performed in the Portal Evaluation Tank (PET). The PET is a semi-cylindrical 7500-1 capacity steel tank, with an opening to the environment of 2.4 m. × 2.4 m. The opening allows installation of doors, feedthroughs, pipes, or other components. The first set of experiments with the PET were conducted in 2016 using hollow doors subjected to a water rise scenario. Data collected during the door tests is being analyzed using Bayesian regression methods to determine the parameters of influence and inform future experiments.

A practical method of simulating full scale wave impacts on components and structures is also being researched to further enhance CFEL capabilities. Early on, the team determined full scale wave impacts could not be simulated using traditional wave flumes or pools; therefore, closed conduit flow is under consideration. Computational fluid dynamics software is being used to simulate fluid velocities associated with tsunami waves of heights up to 6-m, and to design a wave impact simulation device capable of accurately recreating a near vertical wave section with variable height and fluid velocity.

The component flooding simulation activities associated with this project involve use of smoothed particle dynamics codes. These particle-based simulation methods do not require a mesh to be applied to the fluid, which allows for more natural flows to be simulated.

Finally, CFEL can be described as a pioneering element, comprised of several ongoing research and experimental projects, that are vital to the development of risk analysis methods for the nuclear industry.
Three Pressure Peaks Analysis for the TEPCO Fukushima Daiichi Unit 2 by the SAMPSON Code
Authors: Kino Chiaki , Suzuki Hiroaki , Yoshioka Itsuo , Okada Hidetoshi , Naitoh Masanori
Published: October 2017

In view of the 1F decommissioning project, the Institute of Applied Energy (IAE) has been analyzing the course of the accident using the SAMPSON code with an aim to investigate its progression in detail. For 1F Unit-2, certain discrepancies between measurement values and analysis results still exist. For example, although three pressure peaks occur after a manual activation of a safety relief valve (SRV), its mechanism is yet unclear. This study seeks to elucidate the mechanism for the three pressure peaks using a new presumption for the relocation of the debris through the lower part of the core. The current results could reproduce the basic tendency for each peak. However, some deviations between simulation results and measured values indicate the necessity for further improvement of the thermal-hydraulic model used in SAMPSON.
Risk Assessment of Hydrocarbon Pipelines Facing Natural Hazards
Authors: Amórtegui Gil José Vicente
Published: October 2017

Hydrocarbon pipelines are exposed to hazards from natural processes, which may affect their integrity and trigger processes that have consequences on the environment.

Among the natural hazards are the effects of the earthquakes, the neotectonic activity, the volcanism, the weathering of soils and rocks, the landslides, the flows or avalanches of mud or debris, the processes related to sediment transport such as the erosion, the scour by streams, the floods and the sloughing due to rains. Those processes are sometimes related to each other, e.g. the earthquakes can produce slides, or movement of geological faults, or soil liquefaction; the rain can trigger landslides and can cause avalanches and mudslides or debris flow; the volcanic eruptions can originate landslides and avalanches, or pyroclastic flows. Human activities can also induce or accelerate “natural” processes that affect the integrity of the pipelines.

The strength and stiffness of the pipelines allow them to tolerate the effects of natural hazards for some period of time. The amount of time depends on the strength and deformability, the stress state, the age, the conditions of installation and operation of the pipelines and their geometric arrangement with regard to the hazardous processes.

In the programs for pipeline integrity management, the risk is defined as a function that relates the probability of the pipeline rupture and the consequences of the failure. However, some people define risk as the summation of the indicators of probability and consequences, such as a RAM matrix. Others define the risk as the product of the probability of failure times the cost of the consequences, while the overall function used to evaluate the rupture probability of a pipeline facing hazards considered in the ASME b31.8 S standard includes all the elements involved in the failure process. In that standard, for the specific analysis of natural hazards, it is proposed that the function is separated in the two following principal elements: the probability of occurrence of the threatening process (hazard) and the pipeline’s capacity to tolerate it. In this paper a general function is proposed, which is the product of the probability of occurrence of the threatening process, the vulnerability of the pipeline (expressed as the fraction of the potential damage the pipe can undergo), and the consequences of the pipeline failure (represented in the summation of the costs of the spilled product, its collection, the pipeline repair and the damages made by the rupture).
Rainfall Influence Analysis on the Right of Way Stability in Relation With Historical Climate Conditions
Authors: Chaves Agudelo Julián , Aristizábal Ceballos Jaime Hernán , Alvarado Franco Juan Pablo , Lis Felipe Andrés
Published: October 2017

This paper presents the climatic zoning in the Rights-Of-Way (ROW) of Cenit’s infrastructure, in which the spatial and temporal distribution of rainfall was determined by analyzing precipitation information in a time window of 30 years. Rains influence on the ROW stability are exposed in two cases of study, using climatic zoning as a fundamental basis for understanding its effects. The analysis of these case studies allows establishing guidelines for the geohazard management during rainy seasons.
ARPEL/EPGEO: Regional Geotechnics Project — Good Practices in Pipeline Integrity Management to Face Geohazards
Authors: Aristizábal Ceballos Jaime Hernán , García García Hugo Alberto
Published: October 2017

Due to the importance for the Oil and Gas Industry to have a technical document that consolidates the knowledge on management of geohazards for Latin America, the Geotechnics Project Team (EPGEO under its acronym in Spanish) of the Regional Association of Oil, Gas and Biofuels Sector Companies in Latin America and the Caribbean (ARPEL) developed the “Guidelines for Monitoring and Inspection of Pipeline Integrity Management to Face Geohazards” between 2014 and 2016. These guidelines contain the experience of the different operators in the region, given the highly-complex geological-geotechnical pipeline routes (due to the mountain range of the Andes in South America or the Central System in Central America), as well as the high technical requirement derived from the dynamics of the triggering agents in equatorial and tropical areas. In this respect, this document presents the main results of such consolidation and its dissemination, some relevant aspects to be taken into account in interdisciplinary works with reference to third parties, as well as the new guidelines that the EPGEO has proposed to develop that complement the management of geohazards in a Pipeline Transportation System (PTS).
River Crossings: Evaluation of Meander Migration As an Integrity Hazard
Authors: Carnicero Martin
Published: October 2017

TGN operates a system of 9,000 kilometers, with a long stretch traveling next to the foothills. Although it is clear now that this path may not be the best choice, it was defined for access convenience parallel to a national highway back in 1960, when erosion was not an important issue. Whenever a pipeline crossing is located at a place where a river experiences a break in its slope, development of meanders poses a significant threat to its integrity. The interaction between a rigid structure and a changing environment sets the scenario of a problem that needs constant attention. Thus, meanders become the main cause that leads to the implementation of expensive remediation works. In the following paragraphs, a method of evaluating meanders is presented based on concepts of channel stability regarding river curvature, width, slope and flows. This is complemented with real cases in which theoretical aspects are matched with actual crossings, its construction characteristics and the evolution of meanders with time. Long term performance of typical solutions such as soil movement channeling, bank protections, jetties and pipeline lowering are compared. Finally the inverse problem is addressed in which guidelines for the design of a new crossing are listed.
An Initial Approach for Pluviometric Monitoring Along ROWs
Authors: Langone Marcelo Júlio , Piedade Célio Roberto Campos , Oliveira Hudson Régis , Cordeiro Guilherme Licodiedoff , de Paula Henrique Xavier
Published: October 2017

Employing published information and sharing monitoring apparatus and studies, were the initial solution adopted to reach a rain monitoring process in Transpetro (Petrobras Transporte S.A.) southern ROWs. This type of approach can be easily establish and allows the operator to reach satisfactory results, especially for those that has no controlled process at all, where a small amount of information leads for some result even if it is to clarify the need and the resources for such kind of approach.

Even being quite conservative and bit superficially, the process recently established in Transpetro, has already brought a slight economy and safety. Aiming to show the process flow, this paper does not concentrates in reflecting the trigger point, instead it reflects the experience and general methods applied for checking forecasts and rainfall index.
Improving SIMS imaging of FIB bevel cuts with an elaborate sample holder
Authors: Schneider Christian , Weigand Harald , Rohnke Marcus
Published: October 2017

The limited lateral resolution in classical secondary ion mass spectrometry (SIMS) imaging and challenging depth calibration in depth profiling of composite materials restrain the application range for thin film and interface analysis. A motorized sample holder for accurate focused ion beam bevel cuts is designed to artificially increase the interface region. The sample holder is specifically designed for a TOF.SIMS 5 spectrometer by IONTOF, but the basic principle can easily be transferred to other systems. The application of the sample holder is demonstrated with a thin layer model system. A virtual improvement of the lateral resolution by a factor of ten is achieved.
Self-regulated growth of CaVO3 by hybrid molecular beam epitaxy
Authors: Eaton Craig , Lapano Jason , Zhang Lei , Brahlek Matthew , Engel-Herbert Roman
Published: October 2017

The authors report on the growth of stoichiometric CaVO3 thin films on LaSrAlO4 (001) using hybrid molecular beam epitaxy approach, whereby the metalorganic vanadium oxytriisopropoxide (VTIP) and Ca was cosupplied from a gas injector and a conventional effusion cell, respectively. Films were grown using a fixed Ca flux while varying the VTIP flux. Reflection high energy electron diffraction, x-ray diffraction, atomic force microscopy, energy-dispersive x-ray spectroscopy, and high resolution transmission electron microscopy were employed to relate film quality to growth conditions. A wide growth window was discovered in which the films were stoichiometric and film lattice parameter was found independent of the Ca/VTIP flux ratio, allowing more than 10% unintentional deviation in the Ca flux while maintaining stoichiometric growth conditions. Films grown within the growth window showed atomically smooth surfaces with stepped terrace morphology and narrow rocking curves in x-ray diffraction with a full width of half maximum of 8 arc sec, similar to that of the substrate. For growth conditions outside of this window, excess Ca and V nonstoichiometric defects were incorporated into the lattice. The effect of film microstructure and stoichiometry on temperature dependent electrical conductivity is discussed. The ability to produce high quality CaVO3 films without precise control of cation fluxes opens a robust synthesis route to explore the intrinsic physics of strongly correlated metals with reduced dimensionality.
Strong amplitude and phase modulation of optical spatial coherence with surface plasmon polaritons
Authors: Li Dongfang , Pacifici Domenico
Published: October 2017

Surface plasmon polaritons can make incoherent light coherent and vice versa.
Abundance and local-scale processes contribute to multi-phyla gradients in global marine diversity
Authors: Edgar Graham J. , Alexander Timothy J. , Lefcheck Jonathan S. , Bates Amanda E. , Kininmonth Stuart J. , Thomson Russell J. , Duffy J. Emmett , Costello Mark J. , Stuart-Smith Rick D.
Published: October 2017

Latitudinal biodiversity gradients differ between reef fishes and mobile macroinvertebrates at local but not regional scales.
Accelerating metabolism and transmembrane cation flux by distorting red blood cells
Authors: Kuchel Philip W. , Shishmarev Dmitry
Published: October 2017

Glycolysis and transmembrane cation flux (measured by NMR) are accelerated in red blood cells controllably distorted in gels.
Shaping highly regular glass architectures: A lesson from nature
Authors: Schoeppler Vanessa , Reich Elke , Vacelet Jean , Rosenthal Martin , Pacureanu Alexandra , Rack Alexander , Zaslansky Paul , Zolotoyabko Emil , Zlotnikov Igor
Published: October 2017

Protein crystal branching guides the morphogenesis of glass spicules in marine sponges from the class Demospongiae.
Silken promises
Authors: Service Robert F.
Published: October 2017

Spider silk products are finally edging into the market. But mass-produced, superstrong fibers remain out of reach.
Adrenergic nerves activate an angio-metabolic switch in prostate cancer
Authors: Zahalka Ali H. , Arnal-Estapé Anna , Maryanovich Maria , Nakahara Fumio , Cruz Cristian D. , Finley Lydia W. S. , Frenette Paul S.
Published: October 2017

Tumor angiogenesis gets nervous

The microenvironment of solid tumors hosts many intercellular conversations that can either enhance or inhibit tumor growth. Interestingly, the tumor cells need not be direct participants in these conversations. Zahalka
et al.
studied genetically manipulated mouse models and found that adrenergic signals from autonomic nerves in the prostate cancer microenvironment fueled tumor growth by altering the metabolism of blood vessel endothelial cells (see the Perspective by Hayakawa and Wang). These nerve-derived signals suppressed oxidative phosphorylation in the endothelial cells, activating an angiogenic switch that facilitated rapid tumor growth. This cross-talk between nerves and endothelial cells could potentially offer a target for cancer therapies.

Science
, this issue p.
321
; see also p.
305
Recent natural selection causes adaptive evolution of an avian polygenic trait
Authors: Bosse Mirte , Spurgin Lewis G. , Laine Veronika N. , Cole Ella F. , Firth Josh A. , Gienapp Phillip , Gosler Andrew G. , McMahon Keith , Poissant Jocelyn , Verhagen Irene , Groenen Martien A. M. , van Oers Kees , Sheldon Ben C. , Visser Marcel E. , Slate Jon
Published: October 2017

Recent natural selection in a wild bird

Many studies have found evidence of rapid evolution in response to environmental change. In most cases, there has been some suggestion of which traits might be most responsive ahead of time. Bosse
et al.
turn this approach on its head by using genomic regions with a signature of selection to identify traits that are changing. In great tits (
Parus major
) in the United Kingdom, genomic regions showing selection invariably contained genes associated with bill growth. Indeed, U.K. birds not only have longer bills, but these longer bills are associated with increased fitness. These changes likely reflect an increase in domestic garden bird feeders over the past several decades.

Science
, this issue p.
365
Learning-enhanced coupling between ripple oscillations in association cortices and hippocampus
Authors: Khodagholy Dion , Gelinas Jennifer N. , Buzsáki György
Published: October 2017

Memory transfer for long-term storage

Explicit memory formation involves the transfer of rapidly encoded information from the hippocampus to long-term storage sites in the association cortex. Khodagholy
et al.
developed a microelectrode system for large-scale simultaneous electrophysiological monitoring of multiple sites in the rat neocortex. They observed discrete high-frequency neocortical oscillations called ripples only in the association cortex. These cortical ripples shared many properties with hippocampal ripples. Hippocampal ripples were coupled with cortical ripples in the posterior parietal cortex, an association cortical area linked to navigational planning. This coupling was increased during sleep after the induction of long-term hippocampal-dependent spatial memory.

Science
, this issue p.
369
Encoding of vinylidene isomerization in its anion photoelectron spectrum
Authors: DeVine Jessalyn A. , Weichman Marissa L. , Laws Benjamin , Chang Jing , Babin Mark C. , Balerdi Garikoitz , Xie Changjian , Malbon Christopher L. , Lineberger W. Carl , Yarkony David R. , Field Robert W. , Gibson Stephen T. , Ma Jianyi , Guo Hua , Neumark Daniel M.
Published: October 2017

The quantum mechanics of a hydrogen hop

Hydrogen migration between adjacent carbons is widespread in the reaction mechanisms of organic chemistry. DeVine
et al.
used photoelectron spectroscopy to discern the quantum mechanical underpinnings of this 1,2 shift in a prototypical case: conversion of vinylidene (H
2
CC) to acetylene (HCCH). The technique probed specific states of vinylidene by ejecting electrons with varying energies from a negative ion precursor. Experimental data and accompanying theoretical simulations pinpointed a vibrational rocking mode that facilitated the migration. Replacement of hydrogen with its heavier deuterium isotope disrupted this pathway.

Science
, this issue p.
336
Nerves switch on angiogenic metabolism
Authors: Hayakawa Yoku , Wang Timothy C.
Published: October 2017

Adrenergized blood vessels contribute to prostate cancer progression
Prediction of Local Transmission of Mycobacterium tuberculosis Isolates of a Predominantly Beijing Lineage by Use of a Variable-Number Tandem-Repeat Typing Method Incorporating a Consensus Set of Hypervariable Loci
Authors: Murase Yoshiro , Izumi Kiyohiko , Ohkado Akihiro , Aono Akio , Chikamatsu Kinuyo , Yamada Hiroyuki , Igarashi Yuriko , Takaki Akiko , Mitarai Satoshi
Published: October 2017

Strain genotyping based on the variable-number tandem repeat (VNTR) is widely applied for identifying the transmission of
Mycobacterium tuberculosis
. A consensus set of four hypervariable loci (1982, 3232, 3820, and 4120) has been proposed to improve the discrimination of Beijing lineage strains. Herein, we evaluated the utility of these four hypervariable loci for tracing local tuberculosis transmission in 981 cases over a 14-month period in Japan (2010 to 2011). We used six different VNTR systems, with or without the four hypervariable loci. Patient ages and weighted standard distances (a measure of the dispersion of genotype-clustered cases) were used as proxies for estimating local tuberculosis transmission. The highest levels of isolate discrimination were achieved with VNTR systems that incorporated the four hypervariable loci (i.e., the Japan Anti-Tuberculosis Association [JATA]18-VNTR, mycobacterial interspersed repetitive unit [MIRU]28-VNTR, and 24
Beijing
-VNTR). The clustering rates by JATA12-VNTR, MIRU15-VNTR, JATA15-VNTR, JATA18-VNTR, MIRU28-VNTR, and 24
Beijing
-VNTR systems were 52.2%, 51.0%, 39.0%, 24.1%, 23.1%, and 22.0%, respectively. As the discriminative power increased, the median weighted standard distances of the clusters tended to decrease (from 311 to 80 km,
P
< 0.001, Jonckheere-Terpstra trend test). Concurrently, the median ages of patients in the clusters tended to decrease (from 68 to 60 years,
P
< 0.001, Jonckheere-Terpstra trend test). These findings suggest that strain typing using the four hypervariable loci improves the prediction of active local tuberculosis transmission. The four-locus set can therefore contribute to the targeted control of tuberculosis in settings with high prevalence of Beijing lineage strains.
Detection of Plasmodium Species by High-Resolution Melt Analysis of DNA from Blood Smears Acquired in Southwestern Uganda
Authors: Kassaza Kennedy , Operario Darwin J. , Nyehangane Dan , Coffey K. C. , Namugosa Mary , Turkheimer Lena , Ojuka Patrick , Orikiriza Patrick , Mwanga-Amumpaire Juliet , Byarugaba Frederick , Bazira Joel , Guler Jennifer L. , Moore Christopher C. , Boum Yap
Published: October 2017

Microscopic diagnosis of malaria using Giemsa-stained blood smears is the standard of care in resource-limited settings. These smears represent a potential source of DNA for PCR testing to confirm
Plasmodium
infections or for epidemiological studies of archived samples. Therefore, we assessed the use of DNA extracts from stained blood smears for the detection of
Plasmodium
species using real-time PCR. We extracted DNA from archived blood smears and corresponding red blood cell pellets collected from asymptomatic children in southwestern Uganda in 2010. We then performed real-time PCR followed by high-resolution melting (HRM) to identify
Plasmodium
species, and we compared our results to those of microscopy. We analyzed a total of 367 blood smears and corresponding red blood cell pellets, including 185 smears (50.4%) that were positive by microscopy. Compared to microscopy, PCR-HRM analysis of smear DNA had a sensitivity of 93.0% (95% confidence interval [CI], 88.2 to 96.2%) and a specificity of 96.7% (95% CI, 93.0 to 98.8%), and PCR-HRM analysis of pellet DNA had a sensitivity of 100.0% (95% CI, 98.0 to 100.0%) and a specificity of 94.0% (95% CI, 89.4 to 96.9%). Identification of positive PCR-HRM results to the species level revealed
Plasmodium falciparum
(92.0%),
Plasmodium ovale
(5.6%), and
Plasmodium malariae
(2.4%). PCR-HRM analysis of DNA extracts from Giemsa-stained thick blood smears or corresponding blood pellets had high sensitivity and specificity for malaria diagnosis, compared to microscopy. Therefore, blood smears can provide an adequate source of DNA for confirmation of
Plasmodium
species infections and can be used for retrospective genetic studies.
Human Embryonic Stem Cell-Derived Neurons Are Highly Permissive for Varicella-Zoster Virus Lytic Infection
Authors: Sadaoka Tomohiko , Schwartz Cindi L. , Rajbhandari Labchan , Venkatesan Arun , Cohen Jeffrey I.
Published: October 2017

Varicella-zoster virus (VZV) is highly cell associated when grown in culture and has a much higher (4,000- to 20,000-fold increased) particle-to-PFU ratioin vitrothan herpes simplex virus (HSV). In contrast, VZV is highly infectiousin vivoby airborne transmission. Neurons are major targets for VZVin vivo; in neurons, the virus can establish latency and reactivate to produce infectious virus. Using neurons derived from human embryonic stem cells (hESC) and cell-free wild-type (WT) VZV, we demonstrated that neurons are nearly 100 times more permissive for WT VZV infection than very-early-passage human embryonic lung cells or MRC-5 diploid human fibroblasts, the cells used for vaccine production or virus isolation. The peak titers achieved after infection were ∼10-fold higher in human neurons than in MRC-5 cells, and the viral genome copy number-to-PFU ratio for VZV in human neurons was 500, compared with 50,000 for MRC-5 cells. Thus, VZV may not necessarily have a higher particle-to-PFU ratio than other herpesviruses; instead, the cells previously used to propagate virusin vitromay have been suboptimal. Furthermore, based on electron microscopy, neurons infected with VZV produced fewer defective or incomplete viral particles than MRC-5 cells. Our data suggest that neurons derived from hESC may have advantages compared to other cells for studies of VZV pathogenesis, for obtaining stocks of virus with high titers, and for isolating VZV from clinical specimens.

IMPORTANCEVaricella-zoster virus (VZV) causes chickenpox and shingles. Cell-free VZV has been difficult to obtain, both forin vitrostudies and for vaccine production. While numerous cells lines have been tested for their ability to produce high titers of VZV, the number of total virus particles relative to the number of viral particles that can form plaques in culture has been reported to be extremely high relative to that in other viruses. We show that VZV grows to much higher titers in human neurons than in other cell typesin vitroand that the number of total virus genomes relative to the number of viral particles that can form plaques in culture is much lower in human neurons than other cultured cells. These findings indicate that human neurons may be useful for studying VZVin vitro, for growing preparations of virus with high titers, and for isolating the virus from human samples.
Distinct Roles of Cellular ESCRT-I and ESCRT-III Proteins in Efficient Entry and Egress of Budded Virions of Autographa californica Multiple Nucleopolyhedrovirus
Authors: Yue Qi , Yu Qianlong , Yang Qi , Xu Ye , Guo Ya , Blissard Gary W. , Li Zhaofei
Published: October 2017

The endosomal sorting complex required for transport (ESCRT) machinery is necessary for budding of many enveloped viruses. Recently, it was demonstrated that Vps4, the key regulator for recycling of the ESCRT-III complex, is required for efficient infection by the baculovirus Autographa californica multiple nucleopolyhedrovirus (AcMNPV). However, ESCRT assembly, regulation, and function are complex, and little is known regarding the details of participation of specific ESCRT complexes in AcMNPV infection. In this study, the core components of ESCRT-I (Tsg101 and Vps28) and ESCRT-III (Vps2B, Vps20, Vps24, Snf7, Vps46, and Vps60) were cloned from
Spodoptera frugiperda
. Using a viral complementation system and RNA interference (RNAi) assays, we found that ESCRT-I and ESCRT-III complexes are required for efficient entry of AcMNPV into insect cells. In cells knocking down or overexpressing dominant negative (DN) forms of the components of ESCRT-I and ESCRT-III complexes, entering virions were partially trapped within the cytosol. To examine only egress, cells were transfected with the double-stranded RNA (dsRNA) targeting an individual ESCRT-I or ESCRT-III gene and viral bacmid DNA or viral bacmid DNA that expressed DN forms of ESCRT-I and ESCRT-III components. We found that ESCRT-III components (but not ESCRT-I components) are required for efficient nuclear egress of progeny nucleocapsids. In addition, we found that several baculovirus core or conserved proteins (Ac11, Ac76, Ac78, GP41, Ac93, Ac103, Ac142, and Ac146) interact with Vps4 and components of ESCRT-III. We propose that these viral proteins may form an “egress complex” that is involved in recruiting ESCRT-III components to a virus egress domain on the nuclear membrane.

IMPORTANCE
The ESCRT system is hijacked by many enveloped viruses to mediate budding and release. Recently, it was found that Vps4, the key regulator of the cellular ESCRT machinery, is necessary for efficient entry and egress of Autographa californica multiple nucleopolyhedrovirus (AcMNPV). However, little is known about the roles of specific ESCRT complexes in AcMNPV infection. In this study, we demonstrated that ESCRT-I and ESCRT-III complexes are required for efficient entry of AcMNPV into insect cells. The components of ESCRT-III (but not ESCRT-I) are also necessary for efficient nuclear egress of progeny nucleocapsids. Several baculovirus core or conserved proteins were found to interact with Vps4 and components of ESCRT-III, and these interactions may suggest the formation of an “egress complex” involved in the nuclear release or transport of viral nucleocapsids.
Differential Roles for Inner Membrane Complex Proteins across Toxoplasma gondii and
Sarcocystis neurona
Development
Authors: Dubey Rashmi , Harrison Brooke , Dangoudoubiyam Sriveny , Bandini Giulia , Cheng Katherine , Kosber Aziz , Agop-Nersesian Carolina , Howe Daniel K. , Samuelson John , Ferguson David J. P. , Gubbels Marc-Jan
Published: October 2017

The inner membrane complex (IMC) is a defining feature of apicomplexan parasites key to both their motility and unique cell division. To provide further insights into the IMC, we analyzed the dynamics and functions of representative alveolin domain-containing IMC proteins across developmental stages. Our work shows universal but distinct roles for IMC1, -3, and -7 during
Toxoplasma
asexual division but more specialized functions for these proteins during gametogenesis. In addition, we find that IMC15 is involved in daughter formation in both
Toxoplasma
and
Sarcocystis
tachyzoites, bradyzoites, and sporozoites. IMC14 and IMC15 function in limiting the number of
Toxoplasma
offspring per division. Furthermore, IMC7, -12, and -14, which are recruited in the G
1
cell cycle stage, are required for stress resistance of extracellular tachyzoites. Thus, although the roles of the different IMC proteins appear to overlap, stage- and development-specific behaviors indicate that their functions are uniquely tailored to each life stage requirement.
On the classification of finite quasi-quantum groups
Authors: Balodi Mamta , Huang Hua-Lin , Kumar Shiv Datt
Published: October 2017

We give an overview of the classification results obtained so far for finite quasi-quantum groups over an algebraically closed field of characteristic zero. The main classification results on basic quasi-Hopf algebras are obtained by Etingof, Gelaki, Nikshych, and Ostrik, and on dual quasi-Hopf algebras by Huang, Liu and Ye. The objective of this survey is to help in understanding the tools and methods used for the classification.