bluuebunny/crossref_metadata_2025 huggingface dataset:
Loss of fibroblast growth factor 21 action induces insulin resistance, pancreatic islet hyperplasia and dysfunction in mice
Authors: So W Y , Cheng Q , Xu A , Lam K S L , Leung P S
Published: March 2015

Fibroblast growth factor (FGF) 21 is an endocrine factor that normalizes glucose homeostasis and reduces insulin resistance in diabetes. Although the pancreas is an FGF21 target organ, its role in pancreatic islets remains obscure. This study aimed to elucidate the physiological role of FGF21 in pancreatic islets using FGF21-knockout (FGF21-KO) mice. Twenty-four-week-old male global FGF21-KO mice were used in this study. Glucose and insulin tolerance were assessed. Expression of genes and proteins related to islet function and underlying mechanisms were also examined. Islet morphology and insulin-secreting capacity were further evaluated. FGF21-KO mice exhibited insulin resistance while being normoglycemic, associated with increases in beta-cell proliferation and insulin synthesis, acting as compensatory responses. This phenotype probably results from enhanced growth hormone (GH) sensitivity in FGF21-KO mouse islets. In addition, ex vivo FGF21 treatment in normal C57BL/6J mouse islets reduced GH signaling, probably via upregulation of peroxisome proliferator-activated receptor gamma (PPARγ) and cytokine-inducible SH-2 containing (CIS) protein, whereas KO mouse islets displayed reduced PPARγ and CIS expression. FGF21 treatment also reversed GH-induced insulin expression, beta-cell proliferation and GH-impaired glucose-stimulated insulin secretion (GSIS) in islets. Furthermore, distorted islet morphology and impaired GSIS were observed in KO mice, suggestive of islet dysfunction, whereas the enhanced insulin expression and impaired GSIS in FGF21-KO mouse islets could be reversed by blockade of GH signaling. Our data indicate that FGF21 is important in the regulation of beta-cell proliferation and insulin synthesis, probably via modulation of GH signaling. These findings provide evidence that FGF21 is an obligatory metabolic regulator in pancreatic islets and shed new light onto the role of endogenous FGF21 in the pathogenesis of insulin resistance and islet dysfunction.
Ultrafast helicity control of surface currents in topological insulators with near-unity fidelity
Authors: Kastl Christoph , Karnetzky Christoph , Karl Helmut , Holleitner Alexander W.
Published: March 2015

In recent years, a class of solid-state materials, called three-dimensional topological insulators, has emerged. In the bulk, a topological insulator behaves like an ordinary insulator with a band gap. At the surface, conducting gapless states exist showing remarkable properties such as helical Dirac dispersion and suppression of backscattering of spin-polarized charge carriers. The characterization and control of the surface states via transport experiments is often hindered by residual bulk contributions. Here we show that surface currents in Bi2Se3 can be controlled by circularly polarized light on a picosecond timescale with a fidelity near unity even at room temperature. We reveal the temporal separation of such ultrafast helicity-dependent surface currents from photo-induced thermoelectric and drift currents in the bulk. Our results uncover the functionality of ultrafast optoelectronic devices based on surface currents in topological insulators.
Ternary metal fluorides as high-energy cathodes with low cycling hysteresis
Authors: Wang Feng , Kim Sung-Wook , Seo Dong-Hwa , Kang Kisuk , Wang Liping , Su Dong , Vajo John J. , Wang John , Graetz Jason
Published: March 2015

Transition metal fluorides are an appealing alternative to conventional intercalation compounds for use as cathodes in next-generation lithium batteries due to their extremely high capacity (3–4 times greater than the current state-of-the-art). However, issues related to reversibility, energy efficiency and kinetics prevent their practical application. Here we report on the synthesis, structural and electrochemical properties of ternary metal fluorides (M1yM21-yFx: M1, M2=Fe, Cu), which may overcome these issues. By substituting Cu into the Fe lattice, forming the solid–solution CuyFe1-yF2, reversible Cu and Fe redox reactions are achieved with surprisingly small hysteresis (<150 mV). This finding indicates that cation substitution may provide a new avenue for tailoring key electrochemical properties of conversion electrodes. Although the reversible capacity of Cu conversion fades rapidly, likely due to Cu+ dissolution, the low hysteresis and high energy suggest that a Cu-based fluoride cathode remains an intriguing candidate for rechargeable lithium batteries.
Molecular mechanisms of NET formation and degradation revealed by intravital imaging in the liver vasculature
Authors: Kolaczkowska Elzbieta , Jenne Craig N. , Surewaard Bas G. J. , Thanabalasuriar Ajitha , Lee Woo-Yong , Sanz Maria-Jesus , Mowen Kerri , Opdenakker Ghislain , Kubes Paul
Published: March 2015

Neutrophil extracellular traps (NETs) composed of DNA decorated with histones and proteases trap and kill bacteria but also injure host tissue. Here we show that during a bloodstream infection with methicillin-resistant Staphylococcus aureus, the majority of bacteria are sequestered immediately by hepatic Kupffer cells, resulting in transient increases in liver enzymes, focal ischaemic areas and a robust neutrophil infiltration into the liver. The neutrophils release NETs into the liver vasculature, which remain anchored to the vascular wall via von Willebrand factor and reveal significant neutrophil elastase (NE) proteolytic activity. Importantly, DNase although very effective at DNA removal, and somewhat effective at inhibiting NE proteolytic activity, fails to remove the majority of histones from the vessel wall and only partly reduces injury. By contrast, inhibition of NET production as modelled by PAD4-deficiency, or prevention of NET formation and proteolytic activity as modelled in NE−/− mice prevent collateral host tissue damage.
Emergence of reconfigurable wires and spinners via dynamic self-assembly
Authors: Kokot Gasper , Piet David , Whitesides George M. , Aranson Igor S. , Snezhko Alexey
Published: March 2015

Dissipative colloidal materials use energy to generate and maintain structural complexity. The energy injection rate and properties of the environment are important control parameters that influence the outcome of dynamic self-assembly. Here we demonstrate that dispersions of magnetic microparticles confined at the air-liquid interface and energized by a uniaxial in-plane alternating magnetic field, self-assemble into a variety of structures that range from pulsating clusters and single-particle-thick wires to dynamic arrays of spinners (self-assembled short chains) rotating in either direction. The spinners emerge via spontaneous breaking of the uniaxial symmetry of the energizing magnetic field. Demonstration of the formation and disaggregation of particle assemblies suggests strategies to form new meso-scale structures with the potential to perform functions such as mixing and sensing.
In vitro reconstitution of co-translational D1 insertion reveals a role of the cpSec–Alb3 translocase and Vipp1 in photosystem II biogenesis
Authors: Walter Björn , Hristou Athina , Nowaczyk Marc M. , Schünemann Danja
Published: March 2015

Photosystem II (PS II) is a multi-subunit complex localized in the thylakoid membrane that performs the light-dependent photosynthetic charge separation. The PS II reaction centre comprises, among others, the D1 protein. De novo synthesis and repair of PS II require efficient mechanisms for transport and insertion of plastid encoded D1 into the thylakoid membrane. To elucidate the process of D1 insertion, we used an in vitro translation system derived from pea chloroplasts to reconstitute the D1 insertion. Thereby, truncated D1 encoding psbA mRNAs lacking a stop codon were translated in the presence of thylakoid membranes and the translation was stalled by addition of chloramphenicol. The generated ribosome nascent chain complexes (RNCs) were tightly associated with the thylakoids. Subsequently, these D1 insertion intermediates were enriched from solubilized thylakoids by sucrose cushion centrifugation. Immunological analyses demonstrated the presence of the cpSec translocase, Alb3, cpFtsY, cpSRP54 and Vipp1 (vesicle-inducing protein in plastids 1) in the enriched D1 insertion intermediates. A complex formation between cpSecY, Alb3, cpFtsY and Vipp1 in thylakoid membranes was shown by gel filtration chromatography, BN (Blue Native)/SDS-PAGE and co-immunoprecipitation experiments. Furthermore, a stimulating effect of recombinant Vipp1 on the formation of a D1 insertion intermediate was observed in vitro. These results suggest a co-operative function of these proteins in D1 insertion.
Interleukin-34 sustains inflammatory pathways in the gut
Authors: Franzè Eleonora , Monteleone Ivan , Cupi Maria Laura , Mancia Pamela , Caprioli Flavio , Marafini Irene , Colantoni Alfredo , Ortenzi Angela , Laudisi Federica , Sica Giuseppe , Sileri PierPaolo , Pallone Francesco , Monteleone Giovanni
Published: March 2015

IBD (inflammatory bowel disease)-related tissue damage occurs in areas which are massively infiltrated with monocytes/macrophages. These cells respond to inflammatory stimuli with enhanced production of cytokines/chemokines. In the present study, we analysed the expression and role of IL (interleukin)-34, a regulator of monocyte/macrophage differentiation, survival and function, in IBD. A significant increase in IL-34 mRNA and protein expression was seen in inflamed mucosa of patients with CD (Crohn's disease) and patients with UC (ulcerative colitis) compared with the uninvolved areas of the same patients and normal controls. IL-34 was up-regulated in LPMCs (lamina propria mononuclear cells) isolated from normal colon by TNF-α (tumour necrosis factor α) and TLR (Toll-like receptor) ligands and was down-regulated in intestinal biopsies and LPMCs of IBD patients upon treatment with infliximab. Treatment of normal LPMCs with IL-34 increased TNF-α expression in an ERK1/2 (extracellular-signal-regulated kinase 1/2)-dependent fashion and neutralization of IL-34 in IBD mucosal explants reduced TNF-α and IL-6 synthesis. In conclusion, our results indicate that IL-34 is up-regulated in IBD and suggest a role for this cytokine in sustaining the inflammatory responses in this disease.
Aging Affects Identification of Vocal Emotions in Semantically Neutral Sentences
Authors: Dupuis Kate , Pichora-Fuller M. Kathleen
Published: March 2015

Purpose

The authors determined the accuracy of younger and older adults in identifying vocal emotions using the Toronto Emotional Speech Set (TESS; Dupuis & Pichora-Fuller, 2010a) and investigated the possible contributions of auditory acuity and suprathreshold processing to emotion identification accuracy.

Method

In 2 experiments, younger and older adults with normal hearing listened to and identified vocal emotions in the TESS stimuli. The TESS consists of phrases with controlled syntactic, lexical, and phonological properties spoken by an older female talker and a younger female talker to convey 7 emotion conditions (anger, disgust, fear, sadness, neutral, happiness, and pleasant surprise). Participants in both experiments completed audiometric testing; participants in Experiment 2 also completed 3 tests of suprathreshold auditory processing.

Results

Identification by both age groups was above chance for all emotions. Accuracy was lower for older adults in both experiments. The pattern of results was similar across age groups and experiments. Auditory acuity did not predict identification accuracy for either age group in either experiment, nor did performance on tests of auditory processing in Experiment 2.

Conclusions

These results replicate and extend previous findings concerning age-related differences in ability to identify vocal emotions and suggest that older adults' auditory abilities do not explain their difficulties in identifying vocal emotions.
Replicate Measurements of Haemoglobin Mass during a Single Day are Feasible and Precise
Authors: Naef N. , Steiner T. , Wehrlin J.
Published: March 2015

Duplicate haemoglobin mass (Hbmass) measurements are recommended before and after altitude training sojourns to identify individual adaptations in athletes with a high level of certainty. Duplicate measurements reduce typical error (TE) and disclose measurement outliers, but are usually made on separate days, which is not a practical protocol for routine services in elite sport settings. The aim of this study was therefore to investigate whether it is safe (carboxyhaemoglobin<10%) to measure Hbmass twice on the same day and to compare TE with measurements made on separate days. 18 healthy men completed 3 different procedures to measure Hbmass twice a day with the carbon monoxide rebreathing method: A (Hbmass measured twice within 6 h), B (dito A, combined with 1 h of hyperoxic training between the tests), C (dito B, within 2 h). First Hbmass measurements of the 3 test days served as procedure D. Carboxyhaemoglobin did not exceed 10% in any procedure. TE and confidence limits for procedures A, B, C and D were 1.4% (1.0–2.1%), 1.1% (0.8–1.7%), 1.3% (1.0–2.0%) and 1.5% (1.2–2.1%), respectively. Duplicate measurements of Hbmass on the same day are feasible and show TE similar to triplicate measurements on separate days.
Systematic approach to using isentropic stress reverberation techniques in approximating equation of state
Authors: Plume Gifford , Rousseau Carl-Ernst
Published: March 2015

Isentropic stress reverberations are used to obtain multiple Hugoniot states from a single plate impact experiment using a layered plate geometry, where a low impedance inner layer is embedded within a high impedance bulk structure. The mathematical framework used in this technique uses the classical Rankine-Hugoniot equations in the method of impedance matching, where the bulk material is required to have a known Hugoniot. Factors including the wave velocities in the materials, input pulse duration, inner layer thickness, and diameter of the test samples affect the number of states that can be generated from a single experiment. Experiments using 6061 aluminum and polycarbonate, respectively, as the bulk material and inner layer, accurately generated six Hugoniot states for the polycarbonate. Experiments using A572 grade 50 structural steel as the bulk material accurately generated ten Hugoniot states for the polycarbonate. For each experiment, the method can be used to generate a Hugoniot equation defining the material response of the inner layer within the domain encompassed by the specific test. The method is also confined to the low to moderate stress regions, within which Hugoniot and isentropic representations of the material are almost identical.
A novel technique to detect effects of electromagnetic interference by electrostatic discharge simulator to test parameters of tunneling magnetoresistive read heads
Authors: Khunkitti P. , Kaewrawang A. , Siritaratiwat A. , Mewes T. , Mewes C. K. A. , Kruesubthaworn A.
Published: March 2015

Electrostatic discharge (ESD) has been a significant problem in the manufacturing processes of the magnetic recording head technologies for many years. Besides direct discharge damage, ESD can also generate electromagnetic interference (EMI) which could possibly cause failure in magnetic read heads. The aims of this work are to measure the EMI from ESD simulator based on the standard IEC 61000-4-2 and to investigate the effects of EMI on tunneling magnetoresistive (TMR) read heads. The discharge current and the EMI generated by ESD simulator are measured in the experiment. Also, the EMI is applied to the TMR read heads at various amplitudes and distances in order to evaluate the changes of read head parameters including the bit error rate, resistance, read back signal amplitude, and asymmetry parameter of the head. The results show that the discharge current waveform is consistent with the IEC standard current waveform. In addition, it is found that the EMI is insufficient to cause a permanent change of the read head parameters at distances above 2 cm indicating the minimal impact on the head performance. Further experiments are proposed to carry out more detailed studies of the EMI effects on head parameters in order to improve the methods to prevent the degradation of parameters which can be a latent failure in the magnetic read heads.
On the interplay between phonon-boundary scattering and phonon-point-defect scattering in SiGe thin films
Authors: Iskandar A. , Abou-Khalil A. , Kazan M. , Kassem W. , Volz S.
Published: March 2015

This paper provides theoretical understanding of the interplay between the scattering of phonons by the boundaries and point-defects in SiGe thin films. It also provides a tool for the design of SiGe-based high-efficiency thermoelectric devices. The contributions of the alloy composition, grain size, and film thickness to the phonon scattering rate are described by a model for the thermal conductivity based on the single-mode relaxation time approximation. The exact Boltzmann equation including spatial dependence of phonon distribution function is solved to yield an expression for the rate at which phonons scatter by the thin film boundaries in the presence of the other phonon scattering mechanisms. The rates at which phonons scatter via normal and resistive three-phonon processes are calculated by using perturbation theories with taking into account dispersion of confined acoustic phonons in a two dimensional structure. The vibrational parameters of the model are deduced from the dispersion of confined acoustic phonons as functions of temperature and crystallographic direction. The accuracy of the model is demonstrated with reference to recent experimental investigations regarding the thermal conductivity of single-crystal and polycrystalline SiGe films. The paper describes the strength of each of the phonon scattering mechanisms in the full temperature range. Furthermore, it predicts the alloy composition and film thickness that lead to minimum thermal conductivity in a single-crystal SiGe film, and the alloy composition and grain size that lead to minimum thermal conductivity in a polycrystalline SiGe film.
A magnetic minirobot with anchoring and drilling ability in tubular environments actuated by external magnetic fields
Authors: Choi K. , Jeon S. M. , Nam J. K. , Jang G. H.
Published: March 2015

We propose a magnetic minirobot with anchoring and drilling ability (MMAD) controlled by an external magnetic field. The proposed MMAD can navigate through a tubular environment, such as human blood vessels, actuated by a magnetic gradient and uniform rotating magnetic field. It can also generate an anchoring motion, which stably holds the position of the MMAD under pulsatile flow, in order to drill and unclog obstructed blood vessels. The operating conditions of the MMAD were examined by investigating the magnetic torques, and the holding force of the MMAD was measured by a force sensing resistor. Finally, we performed various experiments in a tubular environment to verify the validity of the proposed MMAD.
Understanding of double-curvature shaped magnetoimpedance profiles in Joule-annealed and tensioned microwires at 8–12 GHz
Authors: Popov V. V. , Berzhansky V. N. , Gomonay H. V. , Qin F. X.
Published: March 2015

We have investigated for the first time the combined effect of current and stress on the giant magnetoimpedance characteristics of vanishing-magnetostrictive Co-rich microwires at microwave frequency. As the current-annealed wire is subject to certain tensile stress, one can observe a drastic transformation of field dependence of magnetoimpedance (MI) profiles from smooth shape of a broad peak to deformed shape of a sharp peak with the emergence of a kink on each side. It follows that three different regions—core, inner, and outer shell—have been formed by the combined effect of Joule-annealing, current generated magnetic field, and the tensile stress. A critical field sees a drop of field sensitivity from outer to inner shell and shifts to lower value with increasing annealing current. We successfully adapted our core-shell model to a core-shell-shell model by designating different anisotropy fields for each region to satisfactorily resolve the unique double-curvature shaped peaks in the field derivative MI profiles.
A positioning-tolerant wireless charging system for roadway-powered electric vehicles
Authors: Zhang Zhen , Chau K. T. , Liu Chunhua , Qiu Chun , Ching T. W.
Published: March 2015

This paper proposes a positioning-tolerant wireless power transfer technique to compensate the impact of misalignment on the power transmission performance, which is used to implement the wireless charging functionality in a free-positioning manner, thus significantly improving the practicality for roadway-powered electric vehicles (EVs). The key of the proposed wireless power transfer technique is to adopt the gapless alternate-winding topology for the power supply unit to produce an evenly distributed electromagnetic field and the vertical-and-horizontal coil design for the pickup unit to enhance the capability of acquiring energy. Hence, the power transmission can be effectively improved in spite of an offset between the centers of the primary and secondary coils. In this paper, both the computational simulation and experimentation are carried out to verify the feasibility of the proposed positioning-tolerant wireless charging system for roadway-powered EVs.
Spin Seebeck devices using local on-chip heating
Authors: Wu Stephen M. , Fradin Frank Y. , Hoffman Jason , Hoffmann Axel , Bhattacharya Anand
Published: March 2015

A micro-patterned spin Seebeck device is fabricated using an on-chip heater. Current is driven through a Au heater layer electrically isolated from a bilayer consisting of Fe3O4 (insulating ferrimagnet) and a spin detector layer. It is shown that through this method it is possible to measure the longitudinal spin Seebeck effect (SSE) for small area magnetic devices, equivalent to traditional macroscopic SSE experiments. Using a lock-in detection technique, it is possible to more sensitively characterize both the SSE and the anomalous Nernst effect (ANE), as well as the inverse spin Hall effect in various spin detector materials. By using the spin detector layer as a thermometer, we can obtain a value for the temperature gradient across the device. These results are well matched to values obtained through electromagnetic/thermal modeling of the device structure and with large area spin Seebeck measurements.
Mesoscopic deformation features of shocked porous ceramic: Polycrystalline modeling and experimental observations
Authors: Yu Yin , Wang Wenqiang , He Hongliang , Jiang Tailong , Huan Qiang , Zhang Fuping , Li Yongqiang , Lu Tiecheng
Published: March 2015

To prevent functional failure, the macroscopic shock response of ceramics needs to be understood. We explored the mesoscopic deformation features of porous ceramics, which are responsible for the measured macroscopic “plastic” wave profiles, using polycrystalline modeling and experiments. A polycrystalline model is established that considers the influence of two major microstructures (multi-voids and grain boundaries) in the porous ceramics. Shock experiments with the recovery of shocked porous lead zirconate titanate ceramics were conducted. The computational results show that shear cracks nucleate around voids under shock because of severe shear stress concentrations. Broken fragments fill the voids and lead to void collapse. Representative long-distance extended cracks and thick crevices are observed in the recovered sample subjected to 3.3 GPa compression. These representative features are reproduced by the polycrystalline model. An initial transgranular crack translates into an intergranular crack after a certain propagation range to form a long-distance extended crack. Intergranular cracks branch from the main transgranular crack during main crack propagation to form a thick crevice. The simultaneous propagation of main and branching cracks results in a more effective shock energy dissipation. Slippage and rotation deformation induced by multi-cracks allows the shocked porous ceramic to deform even after all the voids have collapsed. Mesoscopic deformations of porous ceramics induce significant stress relaxations and lead to macroscopic “plastic” wave profiles. The polycrystalline model will aid microstructures design and provide guidance for preventing the shock failure of functional ceramics.
Structural stability and electronic properties of InSb nanowires: A first-principles study
Authors: Zhang Yong , Tang Li-Ming , Ning Feng , Wang Dan , Chen Ke-Qiu
Published: March 2015

Using first-principles calculations, we investigate the structural stability and electronic properties of InSb nanowires (NWs). The results show that, in contrast to the bulk InSb phase, wurtzite (WZ) NWs are more stable than zinc-blende (ZB) NWs when the NW diameter is smaller than 10 nm. Nonpassivated ZB and WZ NWs are found to be metallic and semiconducting, respectively. After passivation, both ZB and WZ NWs exhibit direct-gap semiconductor character, and the band gap magnitude of the NWs strongly depends on the suppression of surface states by the charge-compensation ability of foreign atoms to surface atoms. Moreover, the carrier mobility of the NW can be strengthened by halogen passivation.
Structural changes and conductance thresholds in metal-free intrinsic SiOx resistive random access memory
Authors: Mehonic Adnan , Buckwell Mark , Montesi Luca , Garnett Leon , Hudziak Stephen , Fearn Sarah , Chater Richard , McPhail David , Kenyon Anthony J.
Published: March 2015

We present an investigation of structural changes in silicon-rich silicon oxide metal-insulator-metal resistive RAM devices. The observed unipolar switching, which is intrinsic to the bulk oxide material and does not involve movement of metal ions, correlates with changes in the structure of the oxide. We use atomic force microscopy, conductive atomic force microscopy, x-ray photoelectron spectroscopy, and secondary ion mass spectroscopy to examine the structural changes occurring as a result of switching. We confirm that protrusions formed at the surface of samples during switching are bubbles, which are likely to be related to the outdiffusion of oxygen. This supports existing models for valence-change based resistive switching in oxides. In addition, we describe parallel linear and nonlinear conduction pathways and suggest that the conductance quantum, G0, is a natural boundary between the high and low resistance states of our devices.
Write synchronization for position-correlated granular media
Authors: Hara Akihiro , Muraoka Hiroaki , Greaves Simon J.
Published: March 2015

Jitter noise reduction can be achieved by controlling the position of magnetic grains, but write synchronization is needed to take advantage of the potential reduction. A periodic read-back response can be obtained from DC-erased bits, which is composed of rows of grains. In this paper, the feasibility of creating a clock signal for write synchronization using this periodicity of the read-back response is investigated. As a result, it was confirmed that a clock signal can be created by using the precise periodicity of the read-back response.
Replacing conventional with brown midrib corn silage in a total mixed ration: the impact on early and late lactation dairy cow intake, milk yield and composition, and milk fatty acids profile
Authors: Genero G. A. , Cangiano C. A. , Raimondi J. P. , Roig J. M. , Gagliostro G. A.
Published: March 2015

Brown midrib corn silage (BMRS) is used as an alternative to conventional corn silage (CS) to increase milk yield because of its higher neutral detergent fibre digestibility (NDFD) and DM intake (DMI). Forty Holstein dairy cows were used in a completely randomised design with a 2 × 2 factorial arrangement. Two groups of 13 cows in early lactation (EL) and 7 in late lactation (LL) were fed with a total mixed ration including brown midrib (BMR) or conventional corn silage (C), for a period of 42 days. The cows were milked twice a day, milk yield and DMI were recorded, and NDFD was estimated. Milk composition was measured twice a week and milk fatty acid profile was quantified on the final week of the experiment. In EL, BMR diet increased DMI, NDFD, milk and protein yield whereas milk fat content and yield were decreased. Concentrations of trans-10 C18:1 and trans-10, cis-12 C18:2 in milk were higher in BMR. In LL cows DMI was similar between BMR and C whereas milk and fat yields tended to be higher in C. Fat-corrected milk yield was greater in the C diet. The effect of the BMRS on DMI and milk yield depended on stage of lactation, justifying its use in early lactation. The lower milk fat concentration, observed when BMRS was included in the diets, could be explained in part by an increased concentration of trans-10 C18:1 and trans-10, cis-12 C18:2.
Morpho-anatomical and molecular characterisation of ectomycorrhizae associated with Eucalyptus species growing in different areas of the Punjab Province, Pakistan
Authors: Bashir Hira , Khalid A. N.
Published: March 2015

An evaluation of the ectomycorrhizal status of Eucalyptus plantations in different areas of the Punjab Province, Pakistan is presented. Our study reveals a very low diversity of below-ground ectomycorrhizal fungi associated with Eucalyptus. Through molecular investigation, only three taxa were confirmed to be associated with six different species of Eucalyptus at four sampling sites. Among them, Scleroderma bovista was frequently associated with Eucalyptus in soils having different physicochemical properties highlighting wide ecological amplitude of this species. Scleroderma aurantium and Pisolithus tinctorius were infrequent associates with eucalypt roots. This study is the first consolidated approach to determine the ectomycorrhizal potential of exotic Eucalyptus with the innate fungal flora of Pakistan.
Pleopeltis pleopeltifolia (Polypodiopsida, Polypodiaceae), a poikilochlorophyllous desiccation-tolerant fern: anatomical, biochemical and physiological responses during water stress
Authors: Voytena Ana Paula Lorenzen , Minardi Bruno Degaspari , Barufi José Bonomi , Santos Marisa , Randi Áurea Maria
Published: March 2015

While many ferns have been described as desiccation tolerant (DT), few studies have reported on the mechanisms they use to survive cell desiccation. Among the species belonging to the genus Pleopeltis, P. pleopeltifolia (Raddi) Alston (Polypodiopsida, Polypodiaceae) is a DT species endemic to Brazil. So as to better characterise the mechanisms of desiccation tolerance in ferns, the present study aimed to analyse frond anatomy and physiological changes associated with desiccation and rehydration of P. pleopeltifolia. Fronds are dorsiventral, with uniseriate epidermis. The epidermal cells have various shapes, tending to stretch in the longitudinal direction of the frond. Anticlinal cell walls are sinuous, and periclinal cell walls are convex. Anomocytic stomata are restricted to the abaxial surface. Trichome-type scales are found on both sides of the frond and may play a relevant role in rehydration of this plant when water is available. The mesophyll of the frond consists of palisade parenchyma, tending to a bistratified adaxial surface and spongy parenchyma on abaxial surface. The cuticle on the adaxial surface is conspicuous, ensuring better control of internal water balance. For physiological analyses, sporophytes were subjected to desiccation for 0, 5, 10 and 15 days and rehydration for 1 day. Sporophytes showed a sharp decline in water content when kept without irrigation, reaching 9.6% after 15 days, in addition to wilting and frond rolling. A significant increase in sugar content in fronds was noticeable during desiccation, which may favour a possible osmotic adjustment and vitrification. A notable increase in proline content during rehydration was observed in fronds. During the five initial days of desiccation, the chlorophyll and carotenoid contents decreased abruptly, but after 1 day of rehydration, they had partly recovered. The photosynthetic parameters analysed by fluorescence of chlorophyll a ceased completely after 15 days of desiccation but they had recovered near to pre-desiccation levels after 1 day of rehydration.
Molecular cloning, expression and sequence analysis of a phenylalanine ammonia-lyase gene from Poncirus trifoliata under iron deficiency
Authors: Li Jian-Fu , Zheng Wen-Jun , Zeng Li , Liu Jian-Fu , Wang Ming-Yuan
Published: March 2015

Phenylalanine ammonia-lyase (PAL) is a specific branch point enzyme of primary and secondary metabolism. It is deemed to play a key role in plant development and defence. Homology cloning of the cDNA sequence of PAL gene, Pt-PAL1, from Poncirus trifoliata found a complete open reading frame (ORF) of 2166 bp, with 721 encoded amino acids. The sequence alignment indicated that the amino acid sequence of Pt-PAL1 shared a high identity with PAL genes found in other plants. Both the dominant and catalytic active sites of Pt-PAL1 were similar to PAL proteins observed in Petroselinum crispum. Phylogenetic tree analysis indicated that Pt-PAL1 was more closely related to PALs in Citrus clementina × C. reticulata than to those from other plants. Real-time polymerase chain reaction showed that the expression of Pt-PAL1 gene in roots under iron (Fe) deficiency (0 μM o,o-FeEDDHA) was significantly higher than that under Fe sufficiency (50 μM o,o-FeEDDHA). The same result was noted for total phenolic content. Phenolic compounds play an important role in response to iron deficiency in Strategy I plants. In the present study, root exudates of Poncirus trifoliata strongly promoted the reutilisation of apoplastic Fe in roots. Furthermore, more Fe was desorbed from the cell wall under Fe deficiency than during Fe sufficiency, indicating a relationship between Fe and total phenolics in Strategy I plants under Fe deficiency.
Lost in time and space: re-assessment of conservation status in an arid-zone flora through targeted field survey
Authors: Silcock J. L. , Healy A. J. , Fensham R. J.
Published: March 2015

Lack of basic data to assess plant species against IUCN Red List criteria is a major impediment to assigning accurate conservation status throughout large areas of the world. Erroneous assessments will be most prevalent in vast poorly surveyed areas where herbarium collections are sparse. In arid environments, assessments are further confounded by extreme temporal variability and poor understanding of the nature and magnitude of threats. We systematically re-assess the conservation status of an arid-zone flora. The status of all 1781 vascular plant species occurring across 635 300 km2 of inland eastern Australia was initially assessed through herbarium records and expert interviews. This process generated a list of apparently rare and potentially threatened species, which guided a targeted survey program over 4 years. Search effort and key data on populations of candidate species found were recorded and used to assess 91 species against IUCN criteria. One-third of species were widespread and abundant at least in certain seasons, but had been deemed rare due to sparse collections. The conservation status of 20, mostly newly recognised species from restricted habitats, was upgraded and 14 remained listed because of having restricted areas of occupancy. With the exception of 12 artesian spring species, continuing declines were documented for just six species. The criterion that allows for listing of species because of extreme fluctuations (in combination with restricted and fragmented populations) needs to be carefully interpreted in arid zones, where these fluctuations may be apparent rather than real, and may actually confer resilience to grazing for some species. Our approach facilitates robust conservation assessments across vast and poorly known arid regions, distinguishing species that have merely been lost in space and time from those that are at risk of extinction.
Development of a semi automated dual feed unit to produce FGM coatings using the HVOF thermal spray process
Authors: Mamun K.A. , Stokes J.
Published: March 2015

The application of functionally graded materials (FGMs) is quite difficult, but thermal spray processes like Plasma spray have demonstrated their unique potential in producing graded deposits, where researchers have used twin powder feed systems to mix different proportions of powders. FGMs vary in composition and/or microstructure from one boundary (substrate) to another (top service surface), and innovative characteristics result from the gradient from metals to ceramics or non-metallic to metals. The present study investigates an innovative modification of a high velocity oxy-fuel (HVOF) thermal spray process to produce functionally graded thick coatings. In order to deposit thick coatings, certain problems have to be overcome. Graded coatings enable gradual variation of the coating composition and/or microstructure, which offers the possibility of reducing residual stress build-up with in coatings. In order to spray such a coating, modification to a commercial powder feed hopper was required to enable it to deposit two powders simultaneously which allows deposition of different layers of coating with changing chemical compositions, without interruption to the spraying process. Various concepts for this modification were identified and one design was selected, having been validated through use of a process model, developed using ANSYS Flotran finite element analysis. In the current research the mixing of different proportions of powders were controlled by a computer using LabVIEW software and hardware, which allowed the control and repeatability of the microstructure when producing functionally graded coatings.
Fuzzy energy distribution to a variable consumer load
Authors: Lal Avisekh , Kumar Ravitesh , Mehta Utkal , Vachkov Gancho
Published: March 2015

The paper demonstrates the fuzzy logic based smart distributed system to utilize the available energy optimally. We study the power system with two distributed sources of renewable energy like wind and solar together with normal power grid supply. Through the suitable allotter of the generation ratio from power sources, the distribution generation system, combined with battery bank, can provide user with reliable and constant electric power. Therefore a smart energy distributor is useful to supply energy to consumers such that their demand is supplied optimally depending available energy and battery status. In this work, a new distributor system is tested with fuzzy logic theory to satisfy the load demand constantly at the same time to keep the charging state of the battery at a safe level. Simulation results are also presented to illustrate the potential benefits of the smart distributor by maximizing the usage of renewable energy and depending less on the supply grid.
Isolation and characterisation of rifamycin W and phenylethylamides from a Fijian marine actinomycete Salinispora arenicola
Authors: Ragini Kavita , Aalbersberg William
Published: March 2015

An ansamycin, rifamycin W, and three phenylethylamides, N-(2'-phenylethyl)isobutyramide, 2-methyl-N-(2'-phenylethyl)butyramide, and N-(2'-phenylethyl)isovaleramide were isolated from the fermentation broth of amarine actinomycete strain identified as Salinispora arenicola. The structures of these compounds were confirmed by detailed interpretation of NMR spectroscopic and high resolution ESILC-MS data. Moderate antibacterial activity was observed for rifamycin W only.
Surface ozone profiles at selected South Pacific sites
Authors: Chandra Anand , Koshy Kanayathu , Maata Matakite
Published: March 2015

Surface ozone profiles were studied at Fiji (18.1oS, 178.2oE), Samoa (14.3oS, 170.6oW), Tahiti (18.0oS, 149.0oW), and San Cristobal, Galapagos (0.9oS, 89.6oW) from 1997-2003. Surface ozone levels at these Pacific sites showed a wintertime maximum and a summertime minimum with the lowest mixing ratios occurring at Tahiti and Galapagos, while the highest mixing ratios occurred at Fiji. The seasonal trends at each site were found to be dependent on the varying photochemical sink strength and the changing transport regimes in each season. It was established that the reduced photochemical sink strength in winter was one of the major reasons for the observed increase in surface ozone levels at each site in that season. The presence of the South Pacific Convergence Zone particularly for the Western Pacific (Fiji, Samoa and Tahiti) is the other factor contributing to the observed seasonality and variability in surface ozone levels. The changing frequency of transport from the southern mid-latitude (from high altitudes) is the only transport regime at the boundary layer having the most significant influence on the surface ozone levels at these Pacific sites.
In vitro micro propagation of Nicotiana benthamiana via axillary shoots
Authors: Deo Pradeep C. , Dugdale Benjamin , Harding Robert M. , Kato Maiko , Dale James
Published: March 2015

Axillary shoots of Nicotiana benthamiana were regenerated from nodal explants in two weeks using MS media supplemented with the cytokinin, kinetin (0.5 mg/L), and the auxin, indole-3-butyric acid (IBA) (0.1 mg/L). Ninety two percent of shoots were 2.1-20 mm tall, a size ideal for root induction. After transfer to hormone-free MS they readily produced roots within seven days, with phenotypically normal, fully developed plants being obtained within four weeks. Leaf chlorosis due to iron deficiency was observed in plants over time, however, this was overcome by doubling the concentration of inorganic iron. This rapid micro-propagation system is particularly useful for the in vitro mass production of N. benthamiana plants for various biotechnological applications.
Predicting fire-based perennial bunchgrass mortality in big sagebrush plant communities
Authors: Boyd Chad S. , Davies Kirk W. , Hulet April
Published: March 2015

Maintenance and post-fire rehabilitation of perennial bunchgrasses is important for reducing the spread of exotic annual grass species in big sagebrush plant communities. Post-fire rehabilitation decisions are hampered by a lack of tools for determining extent of fire-induced perennial grass mortality. Our objective was to correlate post-fire characteristics with perennial bunchgrass mortality at the plant and plant community scales. We recorded basal area, percent char, depth of burn and soil colour for 174 bunchgrasses across four ecological sites after a 65 000 ha wildfire in south-east Oregon and assessed plant mortality. Mortality was correlated with post-fire soil colour and ecological site; soil colours (black and grey) associated with pre-fire shrub presence had up to five-fold higher mortality than brown soils typical of interspace locations. Models incorporating depth of burn and soil colour correctly predicted mortality for 90% of individual plants; cover of brown soil explained 88% of the variation in bunchgrass mortality at the plant community scale. Our results indicate that soil colour and depth of burn are accurate predictors of bunchgrass mortality at individual plant and plant community scales and could be used to spatially allocate post-fire bunchgrass rehabilitation resources.
RNA transcribed from a distal enhancer is required for activating the chromatin at the promoter of the gonadotropin α-subunit gene
Authors: Pnueli Lilach , Rudnizky Sergei , Yosefzon Yahav , Melamed Philippa
Published: March 2015

Significance

Much of the mammalian genome recently was shown to be transcribed to long noncoding RNAs, one class of which is the enhancer RNAs (eRNAs) whose levels largely correlate with the mRNA levels of the target gene but whose functions are not yet clear. We examined the eRNA produced from a functional enhancer that directs cell-specific expression of the gonadotropin hormone α-subunit gene, chorionic gonadotropin alpha, in the pituitary. We show that this eRNA plays a crucial role in facilitating DNA looping between the enhancer and promoter and directs histone modifications that are essential for transcription initiation and without which the chromatin becomes repressive to transcription. In this way, the eRNA mediates the function of the enhancer in directing basal gene expression.
RNA virus replication depends on enrichment of phosphatidylethanolamine at replication sites in subcellular membranes
Authors: Xu Kai , Nagy Peter D.
Published: March 2015

Significance

Positive-strand RNA viruses are major pathogens of plants, animals, and humans. These viruses subvert intracellular membranes for virus replication, and lipids are critical due to interaction with viral and coopted host proteins. To dissect the roles of various lipids in Tomato bushy stunt virus (TBSV) replication, we have developed artificial vesicle-based replication assay. Vesicles consisting of a major phospholipid, namely phosphatidylethanolamine (PE), can support TBSV replication by assembling viral replicase complexes and performing a complete replication cycle. Monitoring PE distribution reveals that PE is enriched at the sites of TBSV replication in plant and yeast cells. Increasing PE level in cells leads to enhanced replication of TBSV and other viruses, suggesting that abundant PE in subcellular membranes has proviral function.
Integrin α3β1 regulates kidney collecting duct development via TRAF6-dependent K63-linked polyubiquitination of Akt
Authors: Yazlovitskaya Eugenia M. , Tseng Hui-Yuan , Viquez Olga , Tu Tianxiang , Mernaugh Glenda , McKee Karen K. , Riggins Karen , Quaranta Vito , Pathak Amrita , Carter Bruce D. , Yurchenco Peter , Sonnenberg Arnoud , Böttcher Ralph T. , Pozzi Ambra , Zent Roy
Published: March 2015

The collecting system of the kidney develops from the ureteric bud (UB), which undergoes branching morphogenesis, a process regulated by multiple factors, including integrin–extracellular matrix interactions. The laminin (LM)-binding integrin α3β1 is crucial for this developmental program; however, the LM types and LM/integrin α3β1–dependent signaling pathways are poorly defined. We show that α3 chain–containing LMs promote normal UB branching morphogenesis and that LM-332 is a better substrate than LM-511 for stimulating integrin α3β1–dependent collecting duct cell functions. We demonstrate that integrin α3β1–mediated cell adhesion to LM-332 modulates Akt activation in the developing collecting system and that Akt activation is PI3K independent but requires decreased PTEN activity and K63-linked polyubiquitination. We identified the ubiquitin-modifying enzyme TRAF6 as an interactor with the integrin β1 subunit and regulator of integrin α3β1–dependent Akt activation. Finally, we established that the developmental defects of TRAF6- and integrin α3–null mouse kidneys are similar. Thus K63-linked polyubiquitination plays a previously unrecognized role in integrin α3β1–dependent cell signaling required for UB development and may represent a novel mechanism whereby integrins regulate signaling pathways.