bluuebunny/crossref_metadata_2025 huggingface dataset:
Storage time of platelet concentrates and risk of a positive blood culture: a nationwide cohort study
Authors: Kreuger Aukje L. , Rostgaard Klaus , Middelburg Rutger A. , Kerkhoffs Jean‐Louis H. , Edgren Gustav , Erikstrup Christian , Pedersen Ole B. , Titlestad Kjell , Nielsen Kaspar R. , Ostrowski Sisse R. , Voldstedlund Marianne , van der Bom Johanna G. , Ullum Henrik , Hjalgrim Henrik
Published: November 2017

BACKGROUND

Concern of transfusion‐transmitted bacterial infections has been the major hurdle to extend shelf life of platelet (PLT) concentrates. We aimed to investigate the association between storage time and risk of positive blood cultures at different times after transfusion.

STUDY DESIGN AND METHODS

We performed a nationwide cohort study among PLT transfusion recipients in Denmark between 2010 and 2012, as recorded in the Scandinavian Donations and Transfusions (SCANDAT2) database. Linking with a nationwide database on blood cultures (MiBa), we compared the incidence of a positive blood culture among recipients of PLTs stored 6 to 7 days (old) to those receiving fresh PLTs (1‐5 days), using Poisson regression models. We considered cumulative exposures in windows of 1, 3, 5, and 7 days.

RESULTS

A total of 9776 patients received 66,101 PLT transfusions. The incidence rate ratio (IRR) of a positive blood culture the day after transfusion of at least one old PLT concentrate was 0.77 (95% confidence interval [CI], 0.54‐1.09) compared to transfusion of fresh PLT concentrates. The incidence rate of a positive blood culture was lower the day after receiving one old compared to one fresh PLT concentrate (IRR, 0.57; 95% CI, 0.37‐0.87). Three, 5, or 7 days after transfusion, storage time was not associated with the risk of a positive blood culture.

CONCLUSION

Storage of buffy coat–derived PLT concentrates in PAS‐C up to 7 days seems safe regarding the risk of a positive blood culture. If anything, transfusion of a single old PLT concentrate may decrease this risk the following day.
Evaluation of C‐reactive protein as an inflammatory marker of pemphigus foliaceus and superficial pyoderma in dogs
Authors: Severo Julia So , Santana Aline Elisa , Aoki Valeria , Michalany Nilceo S. , Mantovani Matheus Matioli , Larsson Carlos Eduardo , Larsson Carlos Eduardo
Published: November 2017

Background

C‐reactive protein (CRP) is a major acute phase protein in dogs and may be an inflammatory marker of autoimmune diseases.

Hypothesis/Objectives

To measure pre‐ and post‐treatment CRP levels in dogs with superficial pyoderma (SP) and pemphigus foliaceus (PF) compared to normal dogs; to evaluate possible correlation between CRP values, indirect immunofluorescence (IIF), and pemphigus foliaceus extent and severity index (PEFESI) scores.

Animals

Fifty nine dogs divided into three groups: Group I (control, n = 31), Group II (SP, n = 14) and Group III (PF, n = 14).

Methods

CRP levels were measured in Group I dogs. Skin biopsies of Groups II and III dogs were obtained for histopathological examination. In Group II dogs, CRP levels were measured at days 0, 15, 30 and 60. In Group III dogs were evaluated by PEFESI, IIF and CRP levels at days 0, 15, 30, 60 and 90.

Results

Group III showed a higher median CRP (37.4 mg/mL) compared to the other groups (Group I, CRP 2.9 mg/mL, P < 0.0001; Group II CRP 3.8 mg/mL, P = 0.008). There was no significant difference in CRP levels between groups I and II. IIF titres and CRP levels decreased in most cases of PF with clinical improvement. Dogs with CRP >10.6 μg/mL were 5.5 times more likely to have PF than SP. There was a strong positive correlation between CRP values and PEFESI and a weak positive correlation between CRP values and IIF titres.

Conclusion and clinical importance

CRP levels are increased in dogs with PF and exceed levels found in most dogs with SP.
Frost tolerance, regeneration capacity after frost exposure and high photosystem II efficiency during winter and early spring support high winter survival in Juncus spp.
Authors: Østrem L , Folkestad J , Solhaug K A , Brandsæter L O
Published: November 2017

During the past two decades, significant spread of the perennial weeds Juncus effusus (soft rush) and Juncus conglomeratus (compact rush) in coastal parts of Norway seems to have coincided with an observed rise in winter temperatures. This study investigated the frost tolerance (LT50) and effects of moderate frost exposure on rush plant regrowth over time during the period late November to late winter/spring, and photosynthetic activity in late winter/spring. Juncus effusus and J. conglomeratus of physiologically young age (seedlings) displayed similar high frost tolerance (LT50) and did not differ significantly in regenerative ability following prolonged frost exposure. Regrowth capacity generally increased during winter and when stress conditions increased, shoot formation was prioritised over total biomass production. Maximum quantum efficiency of photosystem II (Fv/Fm) and performance index of photosystem II (PI) were high in late winter/spring, with J. effusus showing higher values than J. conglomeratus. Green, photosynthetically active shoots, which facilitate accumulation of carbohydrates during autumn and even in winter, may provide Juncus spp. with substantial competitiveness in late winter and spring. The results revealed that the dominance of J. effusus over J. conglomeratus in pastures and leys is not due to major differences in winter survival parameters, but probably the higher photosynthetic efficiency observed in J. effusus. Generally higher temperatures during winter and lower frost kill may be contributing to the current increase in rush infestation.
Phylogeny and species diversity of Tasmanian mountain shrimps and their relatives (Crustacea, Anaspidesidae)
Authors: Richter Stefan , Schwentner Martin , Wirkner Christian S. , Ahyong Shane T.
Published: November 2017

Anaspidacea is an enigmatic taxon within Malacostraca with uncertain phylogenetic affinities. One of the four families within Anaspidacea, the Anaspidesidae (representing in most respects the plesiomorphic conditions of the entire taxon), is endemic to Tasmania and shows a remarkable geographical and vertical distribution. Eleven species in three genera (Allanaspides, Anaspides and Paranaspides) are recognized to date, occurring in freshwater habitats such as lakes, rivers, streams, tarns and also in caves. We present the most detailed analyses to date of the phylogeny of Anaspidesidae including all eleven species based on molecular data (COI, 16S and 28S). In addition, the genetic differentiation within the morphologically recognized species is studied and a dating of speciation is given using a molecular clock approach (based on mt‐DNA only). A special focus is on the multiple instances of immigration into the subterranean habitat. Most of the morphologically delineated species are recognized by molecular data. Significantly, however, in at least two cases, the molecular data suggest more species than so far described, but further molecular sampling from a wider range of localities is required. Our molecular divergence estimates suggest the anaspidesids are younger than previously thought. Rather than having Eocene origins, our results suggest Early Miocene origins with primary diversification in Miocene and Pliocene. Entry into subterranean habitats appears to have occurred in the Pleistocene rather than Tertiary. Thus, rather than being a defensive response to rising temperatures in the Tertiary, entry into caves in the Pleistocene may represent opportunistic expansion into new habitats created by the action of glacial meltwaters on existing karst formations. As a result, environmental changes during the Pleistocene appear to have prompted ecological expansion of Anaspides by “opening” new subterranean habitats leading to increased diversification in the group.
EFFECTS OF DUCT BURNER ON BOTTOMING CYCLE IN A COMBINED CYCLE POWER PLANT
Authors: Ganjehkaviri A. , Yusof Mustafa , Mohd Jaafar M. N.
Published: November 2017

In this study, thermodynamic modeling and exergoeconomic assessment of a Combined Cycle Power Plant (CCPP) with a Duct Burner (DB) was performed. Obtaining an optimum condition for the performance of a CCPP, using a DB after gas turbine was investigated by various researchers. DB is installed between gas turbine cycle and Rankine cycle of a CCPP to connect the gas turbine outlet to the Heat Recovery Steam Generator (HRSG) in order to produce steam for bottoming cycle. To find the irreversibility effect in each component of the bottoming cycle, a comprehensive parametric study is performed. In this regard, the effect of DB fuel flow rate on cost efficiency and economic of the bottoming cycle are investigated. To obtain a reasonable result, all the design parameters are kept constant while the DB fuel flow rate is varied. The results indicate that by increasing DB fuel flow rate, the investment cost and the efficiency of CCPP are increased. T-S diagram reveals that by using a DB, higher pressures steam in heat recovery steam generator has higher temperature while the low pressure is decreased. In addition, the exergy of flow gases in heat recovery steam generator increases. So, the exergy efficiency of the whole cycle was increased to around 6 percent, while the cost of the plant reduced by one percent.
NUMERICAL STUDY OF THE EFFECT OF AREA OF MANIFOLD AND INLET/OUTLET FLOW ARRANGEMENT 0N FLOW DISTRIBUTION IN PARALLEL RECTANGULAR MICROCHANNEL COOLING SYSTEM
Authors: M. Sahar Amirah , Shaiful A. I. M.
Published: November 2017

Parallel microchannels have been widely used in cooling of compact electronic equipment due to large contact area with liquid and availability of large mass of fluid to carry away heat. However, understanding of flow distribution for microchannel parallel system is still unclear and there still lack of studies give a clear pictures to understand the complex flow features which cause the flow maldistribution. Generally, the geometrical structure of the manifold and micro channels play an important role in flow distribution between micro channels, which might affects the heat and mass transfer efficiency, even the performance of micro exchangers. A practical design of exchanger basically involves the selection of an optimized solution, keeping an optimal balance between gain in heat transfer and pressure drop penalty. A parallel microchannels configurations consisting inlet and outlet rectangular manifold were simulated to study flow distribution among the channels were investigated numerically by using Ansys Fluent 14.5. The numerical results was validated using existing experimental data and showed a similar trend with values 1% higher than experimental data. The influence of inlet/outlet manifold area and inlet/outlet arrangement on flow distribution in channels were carried out in this study. Based on the predicted flow non-uniformity value, 𝜙, Z- type flow arrangement exhibits higher value of 𝜙, which is 8%, followed by U-type, 2.6% and the I-type, 2.49%. Thus, a better uniformity of velocity and temperature distributions can be achieved in I-shape flow arrangement. The behavior of the flow distributions inside channels is due to the vortices that occurred at manifold. Besides comparing the pressure drop for case 1(D1) and case 2(D2), it is worth to mention that, as the area of inlet and outlet manifold decrease by 50%, the pressure drop is increasing about 5%. However, the inlet/outlet area of manifold on velocity and fluid temperature distributions was insignificant.
COMPUTATIONAL STUDY ON COMBUSTION AND EMISSION CHARACTERISTIC OF PILOTED FLAMES BY VARYING COMPOSITION CO2 OF SIMULATED BIOGAS
Authors: Chin Keat Khor , Mohd Yasin M. F. , Wahid M. A. , Saat A. , Md Yudin A. S.
Published: November 2017

This study investigates the performance of flamelet model technique in predicting the behavior of piloted flame.A non-premixed methane flame of a piloted burner is simulated in OpenFOAM. A detailed chemistry of methane oxidation is integrated with the flamelet combustion model using probability density function (pdf) approach. The turbulence modelling adopts Reynolds Average Navier Stokes (RANS) framework with standard k-ε model. A comparison with experimental data demonstrates good agreement between the predicted and the measured temperature profiles in axial and radial directions. Recently, one of major concern with combustion system is the emission of pollution specially NOx emission. Reduction of the pollutions can be achieved by varying the composition of CO2 in biogas. In addition, the effect of the composition of biogas on NOx emission of piloted burner is still not understood. Therefore, understanding the behavior composition of CO2 in biogas is important that could affect the emission of pollution. In the present study, the use of biogas with composition of 10 to 30 percent of CO2 is simulated to study the effects of biogas composition on NOx emission. The comparison between biogas and pure methane are done based on the distribution of NOx, CO2, CH4, and temperature at different height above the burner. At varying composition of CO2 in biogas, the NOx emission for biogas with 30 percent CO2 is greatly reduced compared to that of 10 percent CO2. This is due to the reduction of the post flame temperature that is produced by the dilution effect at high CO2 concentration.
INVESTIGATION OF TORQUE GENERATION CAPABILITY OF MIXED FLOW TURBINE UNDER STEADY STATE CONDITIONS
Authors: Izaiddin M. A. S. , Mustaffa A. F. , Padzillah M. H.
Published: November 2017

A mixed flow turbine is a type of turbine that is used mostly in turbocharger engine for vehicle. The ability of this turbine in obtain maximum efficiency on a wider operating range makes it more favorable compared to axial turbine and radial turbine. In this project, one of the factors affecting turbine performance which is torque has been studied using simulation. The simulation is then being run by varying the mass flow supply to the turbine. In this simulation, torque generation has been identified and plot on the entire blade surface. This torque generation capability is then been compared between 0.25 kg/s, 0.45 kg/s and 0.65 kg/s mass flow. From the simulation, the torque generated is founded to fluctuate along the turbine blade surface. Besides, the torque generated at the leading edge and trailing edge surface are negative. The magnitude of torque generated increases, as the mass flow increased. At the mid span of the blade, torque generated at 0.25 kg/s, 0.45 kg/s and 0.65 kg/s is -3.73 X 10-3Nm, 4.33 X 10-3Nm, and 11.8 X 10-3Nm respectively.
Three-Dimensional Design Simulations of a High-Energy Density Reshock Experiment at the National Ignition Facility
Authors: Wang Ping , Raman Kumar S. , MacLaren Stephan A. , Huntington Channing M. , Nagel Sabrina R. , Flippo Kirk A. , Prisbrey Shon T.
Published: November 2017

We present simulations of a new experimental platform at the National Ignition Facility (NIF) for studying the hydrodynamic instability growth of a high-energy density (HED) fluid interface that undergoes multiple shocks, i.e., is “reshocked.” In these experiments, indirect-drive laser cavities drive strong shocks through an initially solid, planar interface between a high-density plastic and low-density foam, in either one or both directions. The first shock turns the system into an unstable fluid interface with the premachined initial condition that then grows via the Richtmyer–Meshkov and Rayleigh–Taylor instabilities. Backlit X-ray imaging is used to visualize the instability growth at different times. Our main result is that this new HED reshock platform is established and that the initial data confirm the experiment operates in a hydrodynamic regime similar to what simulations predict. The simulations also reveal new types of edge effects that can disturb the experiment at late times and suggest ways to mitigate them.
Numerical Flow Prediction in Inlet Pipe of Vertical Inline Pump
Authors: Stephen Christopher , Yuan Shouqi , Pei Ji , Cheng G Xing
Published: November 2017

For a pump, the inlet condition of flow determines the outlet conditions of fluid (i.e., energy). As a rule to minimize the losses at the entry of pump, the bends should be avoided as one of the methods. But for the case of vertical inline pump, it is unavoidable in order to save the space for installation. For the purpose of investigation in inlet pipe of vertical inline pump, the unsteady Reynolds-averaged Navier–Stokes equations are solved using the computational fluid dynamics (CFD) code. The results have been shown that there is a good agreement between the performance characteristics obtained from the simulation and experiments. The velocity coefficient from the simulation along the inlet pipe sections is well matched with the theoretical values and found to have variation near the exit of inlet pipe. The pressure and velocity coefficients studies depict the flow physics at each section along with the study of helicity at the exit of inlet pipe to determine the recirculation effects. It is observed that the vortices associated with the motion of the particles are moved toward the surfaces and are more intense than the mean flow. The trends of pressure coefficient at the exit of inlet pipe were addressed with reference to the various flow rates for eight set of radial lines. Hence, this work concludes that for inlet pipe, the generation of circulation was due to the stream path and the reverse flow from the impeller and was reconfirmed with the literature.
Design and Validation of a Soft Switch for a Virtually Variable Displacement Pump
Authors: Beckstrand Brandon K. , Van de Ven James D.
Published: November 2017

Switch-mode hydraulic control is a compact and theoretically efficient alternative to throttling valve control or variable displacement pump control. However, a significant source of energy loss in switch-mode circuits is due to throttling during valve transitions. Hydraulic soft switching was previously proposed as a method of reducing the throttling energy loss, by absorbing, in a small variable volume chamber, the flow that would normally be throttled across the transitioning high-speed valve. An active locking mechanism was previously proposed that overcomes the main challenge with soft switching, which is a lock mechanism that releases quickly and with precise timing. This prior work demonstrated a reduction in energy losses by 66% compared to a control circuit. In this paper, a numerical model is developed for a switch-mode virtually variable displacement pump (VVDP) circuit, utilizing the proposed soft switch. The model is then used as a means of designing a proof of concept prototype to validate the model. The prototype design includes methods for controlling the soft switch spring preload, travel distance, piston displacement required to unlock the soft switch, valve command duty cycle, switching cycle period, and load pressure. Testing demonstrated that the soft switch circuit performed as expected in a baseline condition. The operating region for this prototype was found to be quite narrow. However, the model does a good job of predicting the displacement of the soft switch.
Design of a Crank-Slider Spool Valve for Switch-Mode Circuits With Experimental Validation
Authors: Koktavy Shaun E. , Yudell Alexander C. , Van de Ven James D.
Published: November 2017

A challenge in realizing switch-mode hydraulic circuits is the need for a high-speed valve with fast transition time and high switching frequency. The work presented includes the design and modeling of a suitable valve and experimental demonstration of the prototype in a hydraulic boost converter. The design consists of two spools driven by crank-sliders, designed for 120 Hz maximum switching frequency at a flow rate of 22.7 lpm. The fully open throttling loss is designed for <2% of the rated pressure of 34.5 MPa. The transition time is less than 5% (0.42 ms at 120 Hz) of the total cycle and the duty cycle is adjustable from 0 to 1. Leakage and viscous friction losses in the design are less than 2% of the rated hydraulic energy per cycle. The experimental results agreed well with the model resulting in a 3% variation in transition time. The use of the high-speed valve in a pressure boosts converter demonstrated boost ratio capabilities of 1.08–2.06.
Experimental Investigation of Rotational Effects on Heat Transfer Enhancement Due to Crossflow-Induced Swirl Using Transient Liquid Crystal Thermography
Authors: Yang Li , Singh Prashant , Tyagi Kartikeya , Pandit Jaideep , Ekkad Srinath V. , Ren Jing
Published: November 2017

Rotational effects lead to significant nonuniformity in heat transfer (HT) enhancement and this effect is directly proportional to the rotation number (Ro=ΩD/V). Hence, the development of cooling designs, which have less dependence on rotation, is imperative. This paper studied the effect of rotation on crossflow-induced swirl configuration with the goal of demonstrating a new design that has lesser response toward rotational effects. The new design passes coolant from one pass to the second pass through a set of angled holes to induce impingement and swirling flow to generate higher HT coefficients than typical ribbed channels with 180-deg bend between the two passages. Detailed HT coefficients are presented for stationary and rotating conditions using transient liquid crystal (TLC) thermography. The channel Reynolds number based on the channel hydraulic diameter and channel velocity at inlet/outlet ranged from 25,000 to 100,000. The rotation number ranged from 0 to 0.14. Results show that rotation reduced the HT on both sides of the impingement due to the Coriolis force. The maximum local reduction of HT in the present study was about 30%. Rotation significantly enhanced the HT near the closed end because of the centrifugal force and the “pumping” effect, which caused local HT enhancements up to 100%. Compared to U-bend two pass channels, impingement channels had advantages in the upstream channel and the end region, but HT performance was not beneficial on the leading side of the downstream channel.
Steady-State Analysis of a High-Temperature Natural Circulation Loop Based on Water-Cooled Supercritical CO2
Authors: Sadhu Sayan , Ramgopal Maddali , Bhattacharyya Souvik
Published: November 2017

A high-temperature natural circulation loop (NCL) using supercritical carbon dioxide as loop fluid is modeled to study the effects of operating variables and relevant design parameters on loop performance. The steady-state system model duly considers the axial conduction through loop fluid as well as loop wall and heat transfer with surroundings. The heat source is considered to be a heater with controlled heat flux and the heat sink is modeled as an end heat exchanger with water as the external cold fluid. The governing conservation equations for mass, momentum, and energy are nondimensionalized and are solved numerically discretizing in finite volume method. The numerical results are validated against experimental results reported in the literature in terms of modified Grashof number (Grm) and Reynolds number (Re). Results show that heat loss to the ambient affects the loop performance significantly for the high-temperature loop. It is also observed that the heat input at which the circulation becomes maximum can be increased by increasing either the diameter and/or the loop height. However, better performance is obtained with larger diameter tubes instead of longer loop heights. Axial conduction is seen to have a negligible effect on the overall loop performance. Boussinesq approximation appears to be reasonable as the operating conditions of the supercritical loop are away from the critical point.
Effect of the Aero-Engine Mounting Stiffness on the Whole Engine Coupling Vibration
Authors: Qu M. J. , Chen G.
Published: November 2017

A finite element (FE) model of the rotor tester of an aero-engine, having a thin-walled casing structure, mounted with the way of an actual engine, is developed to simulate the intrinsic vibration characteristics under actual engine-mounting condition. First, a modal experiment of the rotor tester for the whole aero-engine is conducted, and the FE model is modified and validated based on the modal experimental results. Second, the first three orders of natural frequencies and the modal shapes are evaluated using the modified FE model under three different types of mounting stiffness, namely, a fixed mounting boundary, a free mounting boundary, and a flexible mounting boundary. Subsequently, the influences of the mounting stiffness on the coupling vibration of the rotor and stator are studied via a new rotor–stator coupling factor, which is proposed in this study. The results show that the higher the rotor–stator coupling degree of the modal shape, the greater the influence of the mounting condition on the modal shape. Moreover, the influence of the mounting stiffness on the rotor–stator coupling degree is nonlinear. The coupling phenomena of the rotor and stator exist in many modal shapes of actual large turbofan engines, and the effect of mounting stiffness on the rotor–stator coupling cannot be ignored. Hence, the mounting stiffness needs to be considered carefully while modeling the whole aero-engine and simulating the dynamic characteristics of the whole aero-engine.
Investigation of Energy Loss on Fractional Deposition in Last Stages of Condensing Steam Turbine Due to Blade Shape and Moisture Droplet Size
Authors: Sengupta Bidesh , Bhattacharya Chittatosh
Published: November 2017

The steam consumption in a turbine within an operating pressure range determines the effectiveness of thermal energy conversion to electric power generation in a turbo-alternator. The low pressure (LP) stage of the steam turbine produces largest amount of steam to shaft-power in comparison to other stages of turbine although susceptible to various additional losses due to condensation of wet steam near penultimate and ultimate stages. The surface deposition in blade is caused by inertial impaction and turbulent-diffusion. With increasing blade stagger angle along the larger diameter of blading, the fractional deposition of wet steam is largely influenced by blade shape. From this background, the aim of this work is to predict the effect of mathematical models through computational fluid dynamics analysis on the characterization of thermodynamic and mechanical loss components based on unsaturated vapor water droplet size and pressure zones in LP stages of steam turbine and to investigate the influence of droplet size and rotor blade profile on cumulative energy losses due to condensation and provide an indication about the possible conceptual optimization of blade profile design to minimize moisture-induced energy losses.
Performance of Adaptive Lubricants in a Hybrid Journal Bearing Operating Under Fully Saturated Conditions
Authors: Chien Ssu-Ying , Cramer M. S. , Fu Gen , Untaroiu Alexandrina
Published: November 2017

Adaptive lubricants involve binary mixture of synthetic oil and dissolved carbon dioxide (CO2). Unlike conventional lubricant oils, the lubricant viscosity not only varies with the temperature within the bearing but also can be directly adjusted through the CO2 concentration in the system. In this study, we consider the synthetic oil to be fully saturated by CO2 to investigate the maximum impacts of adaptive lubricants on the performance of a hybrid journal bearing. The adaptive lubricant analyzed for this study was the polyalkylene glycol (PAG) oil with low concentration of CO2 (<30%). A three-dimensional (3D) computational fluid dynamic (CFD) model of the bearing was developed and validated against the experimental data. The mixture composition and the resultant mixture viscosity were calculated as a function of pressure and temperature using empirical equations. The simulation results revealed that the viscosity distribution within the PAG/CO2-lubricated bearing is determined primarily by the pressure at the low operating speed. When the speed becomes higher, it is the temperature effect that dominates the viscosity distribution within the bearing. Moreover, the PAG/CO2-lubricated bearing can reduce up to 12.8% power loss than the PAG-lubricated bearing due to the low viscosity of PAG/CO2 mixture. More importantly, we have found that the PAG/CO2 can enhance the load capacity up to 19.6% when the bearing is operating at high-speed conditions.
The prevalence of kilometer-scale heterogeneity in the source region of MORB upper mantle
Authors: Liu Boda , Liang Yan
Published: November 2017

Observed Nd-Hf systematics in natural samples can be reproduced by melting a mantle with heterogeneities on kilometer scale.
Biomass recycling and Earth’s early phosphorus cycle
Authors: Kipp Michael A. , Stüeken Eva E.
Published: November 2017

The scarcity of oxidants in the ancient oceans may have inhibited phosphorus recycling, stifling the growth of the biosphere.
AAAS champions women in science at international events
Authors: Jarvis Michaela
Published: November 2017

Diverse participation maximizes benefits of innovation, speakers say
Webinar | CRISPR unleashed: New tools and applications in live-cell imaging
Authors: Grunwald David , Yildiz Ahmet , Barszczewski Marcin
Published: November 2017

The CRISPR/Cas9 gene editing system has been a boon for researchers, enabling them to manipulate a broad range of genomes quickly and accurately. This novel, versatile tool has been used with great precision for DNA editing as well as a multitude of other applications. Recent enhancements have expanded its abilities; one example is a new, hyperaccurate Cas9 variant that demonstrates high specificity across the genome without compromising on-target activity in human cells. Another is a modification of Cas9 called CRISPRainbow, a system that can more easily label multiple genomic loci in living cells, allowing researchers to better study chromatin dynamics. The unprecedented flexibility of the CRISPR toolset makes it possible to capture imaging phenomena happening at very small scales of space and time. An essential piece of this technology is a camera that captures the fine structure necessary to see the modified DNA (and distinguish it from the background). It must be capable of functioning in challenging environments in living cells, which require cutting-edge light manipulation and detection technologies optimized for light-starved conditions. During this webinar, our experts will examine some of the latest enhancements to the CRISPR/Cas9 system and explain how they are being applied in the lab today.

View the Webinar
GM banana shows promise against deadly fungus strain
Authors: Stokstad Erik
Published: November 2017

Consumer distrust could slip up disease-resistant variety.
An earthly search for gold's cosmic origins
Authors: Cho Adrian
Published: November 2017

Budding factory for heavy nuclei gets boost from discovery of neutron star merger.
Do bacteriophage guests protect human health?
Authors: Guglielmi Giorgia
Published: November 2017

Bacteria-killing viruses are taken up by human epithelial cells, among the hints that they have a role within our body.
Into the hot zone
Authors: Hand Eric , Bickel Chris
Published: November 2017

Into the hot zone
Analysis of
Fusobacterium
persistence and antibiotic response in colorectal cancer
Authors: Bullman Susan , Pedamallu Chandra S. , Sicinska Ewa , Clancy Thomas E. , Zhang Xiaoyang , Cai Diana , Neuberg Donna , Huang Katherine , Guevara Fatima , Nelson Timothy , Chipashvili Otari , Hagan Timothy , Walker Mark , Ramachandran Aruna , Diosdado Begoña , Serna Garazi , Mulet Nuria , Landolfi Stefania , Ramon y Cajal Santiago , Fasani Roberta , Aguirre Andrew J. , Ng Kimmie , Élez Elena , Ogino Shuji , Tabernero Josep , Fuchs Charles S. , Hahn William C. , Nuciforo Paolo , Meyerson Matthew
Published: November 2017

Bacteria go the distance in cancer

The bacterial species
Fusobacterium nucleatum
is associated with a subset of human colorectal cancers, but its role in tumorigenesis is unclear. Studying patient samples, Bullman
et al.
found that
F. nucleatum
and certain co-occurring bacteria were present not only in primary tumors but also in distant metastases. Preliminary evidence suggests that the bacterium is localized primarily within the metastatic cancer cells rather than in the stroma. Antibiotic treatment of mice carrying xenografts of
F. nucleatum
–positive human colorectal cancer slowed tumor growth, consistent with a causal role for the bacterium in tumorigenesis.

Science
, this issue p.
1443
Double-trap measurement of the proton magnetic moment at 0.3 parts per billion precision
Authors: Schneider Georg , Mooser Andreas , Bohman Matthew , Schön Natalie , Harrington James , Higuchi Takashi , Nagahama Hiroki , Sellner Stefan , Smorra Christian , Blaum Klaus , Matsuda Yasuyuki , Quint Wolfgang , Walz Jochen , Ulmer Stefan
Published: November 2017

Nailing down the proton magnetic moment

Fundamental physical laws are believed to remain the same if subjected to three simultaneous transformations: flipping the sign of electric charge, taking a mirror image, and running time backward. To test this charge, parity, and time-reversal (CPT) symmetry, it is desirable to know the fundamental properties of particles such as the proton to high precision. Schneider
et al.
used a double ion trap to determine the magnetic moment of a single trapped proton to a precision of 0.3 parts per billion. Comparatively precise measurements of the same quantity in the antiproton are now needed for a rigorous test of CPT symmetry.

Science
, this issue p.
1081
Major role of nitrite-oxidizing bacteria in dark ocean carbon fixation
Authors: Pachiadaki Maria G. , Sintes Eva , Bergauer Kristin , Brown Julia M. , Record Nicholas R. , Swan Brandon K. , Mathyer Mary Elizabeth , Hallam Steven J. , Lopez-Garcia Purificacion , Takaki Yoshihiro , Nunoura Takuro , Woyke Tanja , Herndl Gerhard J. , Stepanauskas Ramunas
Published: November 2017

Dissolved inorganic carbon fixers revealed

Most of the ocean is dark. Yet it is in this darkness, away from photosynthesizing sunlight, that most planetary carbon cycling occurs. Pachiadaki
et al.
show that nitrite-oxidizing bacteria in one phylum are the predominant fixers of dissolved inorganic carbon in the mesopelagic ocean. The authors sequenced thousands of single amplified genomes of marine prokaryotes. They identified more than 30 nitrite-oxidizing obligate chemoautotrophic bacteria that were unable to transport carbohydrate and that expressed nitrite oxidoreductase. This enzyme provides electrons to drive a reverse tricarboxylic acid cycle that fixes the carbon. Many of the genomes also suggest organisms that have the capacity to produce ammonium and other substrates, possibly to feed nitrite-producing metabolic partners.

Science
, this issue p.
1046
Control of zeolite framework flexibility and pore topology for separation of ethane and ethylene
Authors: Bereciartua Pablo J. , Cantín Ángel , Corma Avelino , Jordá José L. , Palomino Miguel , Rey Fernando , Valencia Susana , Corcoran Edward W. , Kortunov Pavel , Ravikovitch Peter I. , Burton Allen , Yoon Chris , Wang Yu , Paur Charanjit , Guzman Javier , Bishop Adeana R. , Casty Gary L.
Published: November 2017

Purifying ethylene with flexible zeolites

Ethylene is a key feedstock for many chemicals and polymers, but its production requires cryogenic separation from ethane, an energy-consuming step. In theory, pure silica zeolites are well suited to separate olefins from paraffins. Bereciartua
et al.
synthesized a pure silica zeolite with very small pores, which, if static, would not adsorb either of these hydrocarbons. However, molecular dynamics suggested that the pores should be flexible. Indeed, in competitive adsorption experiments, the zeolite preferentially adsorbed ethylene from a mixed stream of ethylene and ethane.

Science
, this issue p.
1068
Valuing water for sustainable development
Authors: Garrick Dustin E. , Hall Jim W. , Dobson Andrew , Damania Richard , Grafton R. Quentin , Hope Robert , Hepburn Cameron , Bark Rosalind , Boltz Frederick , De Stefano Lucia , O'Donnell Erin , Matthews Nathanial , Money Alex
Published: November 2017

Measurement and governance must advance together
As the extension, so the twist
Authors: Coulais Corentin
Published: November 2017

Artificial internal structures blur the boundary between materials and machines
Editing peptide presentation to T cells
Authors: Cresswell Peter
Published: November 2017

Structures reveal how high-affinity peptides are presented to induce immune responses
Channelrhodopsin reveals its dark secrets
Authors: Gerwert Klaus
Published: November 2017

A high-resolution structure of channelrhodopsin 2 provides key insights for optogenetics
Viruses hijack a host lncRNA to replicate
Authors: Kotzin Jonathan J. , Mowel Walter K. , Henao-Mejia Jorge
Published: November 2017

Viruses induce a host lncRNA to rewire cellular metabolism to promote their replication
Blurring disciplinary boundaries
Authors: McBean Gordon , Martinelli Alberto
Published: November 2017

The ambitious and integrated framework of the United Nations (UN) Sustainable Development Goals (SDGs) demonstrates that complex global problems span the natural and social sciences and that solutions to such problems demand a joint approach of the two. Despite decades of efforts toward better integration, much of society still presumes a stark divide between the disciplines, and most scientists continue to be trained, evaluated, and rewarded in disciplinary silos. The recent merger of the International Council for Science (ICSU) and the International Social Science Council (ISSC)—leading international councils of the natural and social sciences, respectively—sends a powerful message that the future of science depends on collapsing the walls between academic disciplines.
Complete Chloroplast Genome Sequence of
Chenopodium album
from Northeastern India
Authors: Devi Rajkumari Jashmi , Thongam Biseshwori
Published: November 2017

Chenopodium album
belongs to the complex genus
Chenopodium
of the family Amaranthaceae. It is an economically and medicinally important plant. We report here the first complete chloroplast genome sequence of
C. album
from northeastern India. This study shall add extensive information on the evolutionary relationships of the genus
Chenopodium
.
Complete Chloroplast Genome Sequence of Cane Needle Grass,
Nassella hyalina
(Poaceae: Stipeae)
Authors: Wang Aisuo , Wu Hanwen , Gopurenko David
Published: November 2017

Nassella hyalina
(cane needle grass) is on the Alert List for Environmental Weeds in Australia. We present here the first complete chloroplast sequence of
N. hyalina
reconstructed from Illumina whole-genome sequencing. The complete chloroplast sequence is 137,606 bp in size and has a gene content and structure similar to those of other published chloroplast genomes of Stipeae.
Draft Genome Sequences of Aggregatibacter actinomycetemcomitans Strains 310a and 310b
Authors: May Anthony C. , Ohta Hiroyuki , Maeda Hiroshi , Kokeguchi Susumu , Cugini Carla
Published: November 2017

We report the draft genome sequences of
Aggregatibacter actinomycetemcomitans
strains 310a (310-TR) and 310b (310-OS). Strain 310a is a clinical isolate with a rough phenotype. Strain 310b is a laboratory-adapted isolate derived from the passage of 310a and displays a smooth phenotype.
Draft Genome Sequence of
Burkholderia puraquae
Type Strain CAMPA 1040, Isolated from Hospital Settings in Córdoba, Argentina
Authors: Leguizamon Mariana , Draghi Walter O. , Montanaro Patricia , Schneider Andy , Prieto Claudia I. , Martina Pablo , Lagares Antonio , Lasch Peter , Bosch Alejandra
Published: November 2017

We report here the draft genome sequence of
Burkholderia puraquae
type strain CAMPA 1040, a member of the
Burkholderia cepacia
complex. This strain, isolated from a hemodialysis water reservoir, harbors several stress tolerance genes, such as the systems for low oxygen survival, for copper tolerance, and for osmotic stress resistance.
Complete Genome Sequence of a Novel Variant of Wenzhou Mammarenavirus
Authors: Liu Meng-meng , Li Li-li , Wang Xiao-feng , Duan Zhao-jun
Published: November 2017

Wenzhou mammarenavirus (WENV) is a novel species of
Arenavirus
that was first detected in China. We report here a novel WENV variant (WENV G107) from liver samples of
Rattus norvegicus
that shares 84.7% to 86.8% (large [L] segment) and 84.2% to 87.8% (small [S] segment) nucleotide sequence identity with its closest relative. The genomic characteristics were analyzed based on the whole genome of WENV G107.
Metagenome of the Siberian Underground Water Reservoir
Authors: Kadnikov Vitaly V. , Frank Yulia A. , Mardanov Andrey V. , Beletsky Alexey V. , Karnachuk Olga V. , Ravin Nikolai V.
Published: November 2017

We report on the metagenome of a deep subsurface aquifer in the Tomsk region of Russia, sampled via an oil exploration borehole drilled to a depth of 2.8 km. Methanogenic archaea were present in the water along with members of various bacterial phyla, including
Firmicutes
,
Chloroflexi
,
Bacteroidetes
,
Ignavibacteriae
, and uncultured candidate divisions.
Complete Genome Sequences of Two Plant-Associated Pseudomonas putida Isolates with Increased Heavy-Metal Tolerance
Authors: Nesme Joseph , Cania Barbara , Zadel Urška , Schöler Anne , Płaza Grażyna A. , Schloter Michael
Published: November 2017

We report here the complete genome sequences of two
Pseudomonas putida
isolates recovered from surface-sterilized roots of
Sida hermaphrodita
. The two isolates were characterized by an increased tolerance to zinc, cadmium, and lead. Furthermore, the strains showed typical plant growth-promoting properties, such as the production of indole acetic acid, cellulolytic enzymes, and siderophores.
First Complete Genome Sequences of Anopheles A Virus of the Genus
Orthobunyavirus
Authors: Hughes Holly R. , Russell Brandy J. , Lambert Amy J.
Published: November 2017

Here, we report the first complete genome sequence of Anopheles A virus (ANAV) that was isolated from Colombia in 1940, and we include the first description of the medium and large segments. The ANAV medium and large segments share the highest identity with serogroup member Lukuni virus, which causes human infection.
Draft Genome Sequence of Pseudomonas fluorescens Strain TR3, a Potential Biocontrol Agent against the Rice Blast Fungus Magnaporthe oryzae
Authors: Zhang Xue , Xu Jin-Rong , Nakatsu Cindy H.
Published: November 2017

We present the draft genome sequence of the potential biocontrol agent
Pseudomonas fluorescens
TR3, which was isolated from rice leaves infected with
Magnaporthe oryzae
in a greenhouse. The genome of TR3 was assembled into 26 scaffolds (~6 Mbp) and includes genes potentially involved in bacterial interactions with fungi.
The Whole-Genome Sequence of Bacillus velezensis Strain SB1216 Isolated from the Great Salt Plains of Oklahoma Reveals the Presence of a Novel Extracellular RNase with Antitumor Activity
Authors: Marasini Daya , Cornell Carolyn R. , Oyewole Opeoluwa , Sheaff Robert J. , Fakhr Mohamed K.
Published: November 2017

The whole-genome sequence of
Bacillus velezensis
strain SB1216, isolated from the Great Salt Plains of Oklahoma, showed the presence of a 3,814,720-bp circular chromosome and no plasmids. The presence of a novel 870-bp extracellular RNase gene is predicted to be responsible for this strain’s antitumor activity.
Complete Genome Sequences of Plasmid-Bearing Multidrug-Resistant Campylobacter jejuni and Campylobacter coli Strains with Type VI Secretion Systems, Isolated from Retail Turkey and Pork
Authors: Marasini Daya , Fakhr Mohamed K.
Published: November 2017

We report the complete genome sequences of multidrug-resistant
Campylobacter jejuni
and
Campylobacter coli
isolated from retail turkey and pork, respectively. The chromosomes of these two isolates contained type VI secretion system genes. The two isolates also harbored large plasmids with antimicrobial resistance genes possibly contributing to their multidrug resistance.
Global Transcriptome Analysis of Aedes aegypti Mosquitoes in Response to Zika Virus Infection
Authors: Etebari Kayvan , Hegde Shivanand , Saldaña Miguel A. , Widen Steven G. , Wood Thomas G. , Asgari Sassan , Hughes Grant L.
Published: November 2017

Vector-borne viruses pose great risks to human health. Zika virus has recently emerged as a global threat, rapidly expanding its distribution. Understanding the interactions of the virus with mosquito vectors at the molecular level is vital for devising new approaches in inhibiting virus transmission. In this study, we embarked on analyzing the transcriptional response of
Aedes aegypti
mosquitoes to Zika virus infection. Results showed large changes in both coding and long noncoding RNAs. Analysis of these genes showed similarities with other flaviviruses, including dengue virus, which is transmitted by the same mosquito vector. The outcomes provide a global picture of changes in the mosquito vector in response to Zika virus infection.
Relative Impact of Complement Receptors CD21/35 (Cr2/1) on Scrapie Pathogenesis in Mice
Authors: Kane Sarah J. , Swanson Eric , Gordon Elizabeth O. , Rocha Savannah , Bender Heather R. , Donius Luke R. , Aguzzi Adriano , Hannan Jonathan P. , Zabel Mark D.
Published: November 2017

Mammalian prion diseases are caused by prions, unique infectious agents composed primarily, if not solely, of a pathologic, misfolded form of a normal host protein, the cellular prion protein (PrPC). Prions replicate without a genetic blueprint, but rather contact PrPCand coerce it to misfold into more prions, which cause neurodegeneration akin to other protein-misfolding diseases like Alzheimer’s disease. A single gene produces two alternatively spliced mRNA transcripts that encode mouse complement receptors CD21/35, which promote efficient prion replication in the lymphoid system and eventual movement to the brain. Here we show that CD21/35 are high-affinity prion receptors, but mice expressing only CD21 die from prion disease sooner than CD35-expressing mice, which contain less prions early after infection and exhibit delayed terminal disease, likely due to their less organized splenic follicles. Thus, CD21 appears to be more important for defining splenic architecture that influences prion pathogenesis.