bluuebunny/crossref_metadata_2025 huggingface dataset:
Mapping private keys into one public key using binary matrices and masonic cipher: Caesar cipher as a case study
Authors: Manasrah Ahmad M. , Al‐Din Basim Najim
Published: February 2016

Caesar cipher is a mono alphabetic cipher. It is also a type of substitution cipher in which each letter in the plaintext is “shifted” a certain number of places down the alphabet. However, Caesar cipher method did not last long because of its simplicity and lack of communication security. Therefore, we believe that strengthen the key mechanism should increase its complexity against the various cryptanalysis attacks. This paper proposes an enhanced Caesar cipher method through adopting two private keys that are tied to the character positions (i.e. odd and even) for encryption and/or decryption. The two private keys are mapped into one public key to be transferred to the recipient. At the end, the results show that the new cryptosystem is inevitable to cryptanalysis attack. And the cipher text is reduced in size and thus, memory space. The public key generation process is proven to be a one‐way function utilizing binary matrices that are generated and shared between the two communicating parties. Copyright © 2016 John Wiley & Sons, Ltd.
Corporate Ownership, Control, and Firm Performance in Victorian Britain
Authors: Acheson Graeme G. , Campbell Gareth , Turner John D. , Vanteeva Nadia
Published: February 2016

Scholars have long debated whether ownership matters for firm performance. The standard view regarding Victorian Britain is that family-controlled companies had a detrimental effect on performance. In this article, we examine this view using a hand-collected corporate ownership dataset. Our main finding is that it was not necessarily the broad structure of corporate ownership that mattered for performance, but whether family blockholders had a governance role. Large active blockholders tended to increase operating performance, implying that they reduced managerial expropriation. Contrastingly, we find that directors who were independent of large owners were more likely to increase shareholder value.
Clans and Ploughs: Traditional Institutions and Production Decisions of Kazakhs under Russian Colonial Settlement
Authors: Guirkinger Catherine , Aldashev Gani
Published: February 2016

This article investigates how, with increasing land pressure during Russian settlement in Kazakh steppes in the late nineteenth century, clan institutions affected the transition from nomadic pastoralism to settled agriculture. Using a novel dataset constructed from Russian colonial expedition materials matched with clan genealogies, we find that, controlling for geographic factors, clan identity strongly influenced the duration of transhumance period, the organization of production, and the acquisition of new agricultural tools. Information transmission within clans, external economies of scale in nomadic pastoralism, and clan-specific values and norms underlie the results.
Characterization of Al2O3 in High-Strength Mo Alloy Sheets by High-Resolution Transmission Electron Microscopy
Authors: Zhou Yucheng , Gao Yimin , Wei Shizhong , Hu Yajie
Published: February 2016

A novel type of alumina (Al2O3)-doped molybdenum (Mo) alloy sheet was prepared by a hydrothermal method and a subsequent powder metallurgy process. Then the characterization of α-Al2O3 was investigated using high-resolution transmission electron microscopy as the research focus. The tensile strength of the Al2O3-doped Mo sheet is 43–85% higher than that of the pure Mo sheet, a very obvious reinforcement effect. The sub-micron and nanometer-scale Al2O3 particles can increase the recrystallization temperature by hindering grain boundary migration and improve the tensile strength by effectively blocking the motion of the dislocations. The Al2O3 particles have a good bond with the Mo matrix and there exists an amorphous transition layer at the interface between Al2O3 particles and the Mo matrix in the as-rolled sheet. The sub-structure of α-Al2O3 is characterized by a number of nanograins in the
$\left[ {2\bar{2}1} \right]$
direction. Lastly, a new computer-based method for indexing diffraction patterns of the hexagonal system is introduced, with 16 types of diffraction patterns of α-Al2O3 indexed.
Neuregulin-1 attenuates cognitive function impairments in a transgenic mouse model of Alzheimer’s disease
Authors: Ryu J , Hong B-H , Kim Y-J , Yang E-J , Choi M , Kim H , Ahn S , Baik T-K , Woo R-S , Kim H-S
Published: February 2016

The neuregulin (NRG) family of epidermal growth factor-related proteins is composed of a wide variety of soluble and membrane-bound proteins that exert their effects via the tyrosine kinase receptors ErbB2-ErbB4. In the nervous system, the functions of NRG1 are essential for peripheral myelination, the establishment and maintenance of neuromuscular and sensorimotor systems and the plasticity of cortical neuronal circuits. In the present study, we report that an intracerebroventricular infusion of NRG1 attenuated cognitive impairments in 13-month-old Tg2576 mice, an animal model of Alzheimer’s disease (AD). In addition, according to Golgi-Cox staining, NRG1 rescued the reduction in the number of dendritic spines detected in the brains of Tg2576 mice compared with vehicle (PBS)-infused mice. This result was also corroborated in vitro as NRG1 attenuated the oligomeric amyloid beta peptide1-42 (Aβ1-42)-induced decrease in dendritic spine density in rat primary hippocampal neuron cultures. NRG1 also alleviated the decrease in neural differentiation induced by oligomeric Aβ1-42 in mouse fetal neural stem cells. Collectively, these results suggest that NRG1 has a therapeutic potential for AD by alleviating the reductions in dendritic spine density and neurogenesis found in AD brains.
Nicotinamide mononucleotide adenylyltransferase promotes hypoxic survival by activating the mitochondrial unfolded protein response
Authors: Mao X R , Kaufman D M , Crowder C M
Published: February 2016

Gain-of-function mutations in the mouse nicotinamide mononucleotide adenylyltransferase type 1 (Nmnat1) produce two remarkable phenotypes: protection against traumatic axonal degeneration and reduced hypoxic brain injury. Despite intensive efforts, the mechanism of Nmnat1 cytoprotection remains elusive. To develop a new model to define this mechanism, we heterologously expressed a mouse Nmnat1 non-nuclear-localized gain-of-function mutant gene (m-nonN-Nmnat1) in the nematode Caenorhabditis elegans and show that it provides protection from both hypoxia-induced animal death and taxol-induced axonal pathology. Additionally, we find that m-nonN-Nmnat1 significantly lengthens C. elegans lifespan. Using the hypoxia-protective phenotype in C. elegans, we performed a candidate screen for genetic suppressors of m-nonN-Nmnat1 cytoprotection. Loss of function in two genes, haf-1 and dve-1, encoding mitochondrial unfolded protein response (mitoUPR) factors were identified as suppressors. M-nonN-Nmnat1 induced a transcriptional reporter of the mitoUPR gene hsp-6 and provided protection from the mitochondrial proteostasis toxin ethidium bromide. M-nonN-Nmnat1 was also protective against axonal degeneration in C. elegans induced by the chemotherapy drug taxol. Taxol markedly reduced basal expression of a mitoUPR reporter; the expression was restored by m-nonN-Nmnat1. Taken together, these data implicate the mitoUPR as a mechanism whereby Nmnat1 protects from hypoxic and axonal injury.
Cdk12 Is A Gene-Selective RNA Polymerase II Kinase That Regulates a Subset of the Transcriptome, Including Nrf2 Target Genes
Authors: Li Xuan , Chatterjee Nirmalya , Spirohn Kerstin , Boutros Michael , Bohmann Dirk
Published: February 2016

The Nrf2 transcription factor is well conserved throughout metazoan evolution and serves as a central regulator of adaptive cellular responses to oxidative stress. We carried out an RNAi screen in Drosophila S2 cells to better understand the regulatory mechanisms governing Nrf2 target gene expression. This paper describes the identification and characterization of the RNA polymerase II (Pol II) kinase Cdk12 as a factor that is required for Nrf2 target gene expression in cell culture and in vivo. Cdk12 is, however, not essential for bulk mRNA transcription and cells lacking CDK12 function are viable and able to proliferate. Consistent with previous findings on the DNA damage and heat shock responses, it emerges that Cdk12 may be specifically required for stress activated gene expression. Transcriptome analysis revealed that antioxidant gene expression is compromised in flies with reduced Cdk12 function, which makes them oxidative stress sensitive. In addition to supporting Reactive Oxygen Species (ROS) induced gene activation, Cdk12 suppresses genes that support metabolic functions in stressed conditions. We suggest that Cdk12 acts as a gene-selective Pol II kinase that engages a global shift in gene expression to switch cells from a metabolically active state to “stress-defence mode” when challenged by external stress.
Kondo-like zero-bias conductance anomaly in a three-dimensional topological insulator nanowire
Authors: Cho Sungjae , Zhong Ruidan , Schneeloch John A. , Gu Genda , Mason Nadya
Published: February 2016

Zero-bias anomalies in topological nanowires have recently captured significant attention, as they are possible signatures of Majorana modes. Yet there are many other possible origins of zero-bias peaks in nanowires—for example, weak localization, Andreev bound states, or the Kondo effect. Here, we discuss observations of differential-conductance peaks at zero-bias voltage in non-superconducting electronic transport through a 3D topological insulator (Bi1.33Sb0.67)Se3 nanowire. The zero-bias conductance peaks show logarithmic temperature dependence and often linear splitting with magnetic fields, both of which are signatures of the Kondo effect in quantum dots. We characterize the zero-bias peaks and discuss their origin.
High-quality photonic crystals with a nearly complete band gap obtained by direct inversion of woodpile templates with titanium dioxide
Authors: Marichy Catherine , Muller Nicolas , Froufe-Pérez Luis S. , Scheffold Frank
Published: February 2016

Photonic crystal materials are based on a periodic modulation of the dielectric constant on length scales comparable to the wavelength of light. These materials can exhibit photonic band gaps; frequency regions for which the propagation of electromagnetic radiation is forbidden due to the depletion of the density of states. In order to exhibit a full band gap, 3D PCs must present a threshold refractive index contrast that depends on the crystal structure. In the case of the so-called woodpile photonic crystals this threshold is comparably low, approximately 1.9 for the direct structure. Therefore direct or inverted woodpiles made of high refractive index materials like silicon, germanium or titanium dioxide are sought after. Here we show that, by combining multiphoton lithography and atomic layer deposition, we can achieve a direct inversion of polymer templates into TiO2 based photonic crystals. The obtained structures show remarkable optical properties in the near-infrared region with almost perfect specular reflectance, a transmission dip close to the detection limit and a Bragg length comparable to the lattice constant.
New strategy for drug discovery by large-scale association analysis of molecular networks of different species
Authors: Zhang Bo , Fu Yingxue , Huang Chao , Zheng Chunli , Wu Ziyin , Zhang Wenjuan , Yang Xiaoyan , Gong Fukai , Li Yuerong , Chen Xiaoyu , Gao Shuo , Chen Xuetong , Li Yan , Lu Aiping , Wang Yonghua
Published: February 2016

The development of modern omics technology has not significantly improved the efficiency of drug development. Rather precise and targeted drug discovery remains unsolved. Here a large-scale cross-species molecular network association (CSMNA) approach for targeted drug screening from natural sources is presented. The algorithm integrates molecular network omics data from humans and 267 plants and microbes, establishing the biological relationships between them and extracting evolutionarily convergent chemicals. This technique allows the researcher to assess targeted drugs for specific human diseases based on specific plant or microbe pathways. In a perspective validation, connections between the plant Halliwell-Asada (HA) cycle and the human Nrf2-ARE pathway were verified and the manner by which the HA cycle molecules act on the human Nrf2-ARE pathway as antioxidants was determined. This shows the potential applicability of this approach in drug discovery. The current method integrates disparate evolutionary species into chemico-biologically coherent circuits, suggesting a new cross-species omics analysis strategy for rational drug development.
Accumulation of p53 via down-regulation of UBE2D family genes is a critical pathway for cadmium-induced renal toxicity
Authors: Lee Jin-Yong , Tokumoto Maki , Fujiwara Yasuyuki , Hasegawa Tatsuya , Seko Yoshiyuki , Shimada Akinori , Satoh Masahiko
Published: February 2016

Chronic cadmium (Cd) exposure can induce renal toxicity. In Cd renal toxicity, p53 is thought to be involved. Our previous studies showed that Cd down-regulated gene expression of the UBE2D (ubiquitin-conjugating enzyme E2D) family members. Here, we aimed to define the association between UBE2D family members and p53-dependent apoptosis in human proximal tubular cells (HK-2 cells) treated with Cd. Cd increased intracellular p53 protein levels and decreased UBE2D2 and UBE2D4 gene expression via inhibition of YY1 and FOXF1 transcription factor activities. Double knockdown of UBE2D2 and UBE2D4 caused an increase in p53 protein levels and knockdown of p53 attenuated not only Cd-induced apoptosis, but also Cd-induced apoptosis-related gene expression (BAX and PUMA). Additionally, the mice exposed to Cd for 6 months resulted in increased levels of p53 and induction of apoptosis in proximal tubular cells. These findings suggest that down-regulation of UBE2D family genes followed by accumulation of p53 in proximal tubular cells is an important mechanism for Cd-induced renal toxicity.
Steering Bell-diagonal states
Authors: Quan Quan , Zhu Huangjun , Liu Si-Yuan , Fei Shao-Ming , Fan Heng , Yang Wen-Li
Published: February 2016

We investigate the steerability of two-qubit Bell-diagonal states under projective measurements by the steering party. In the simplest nontrivial scenario of two projective measurements, we solve this problem completely by virtue of the connection between the steering problem and the joint-measurement problem. A necessary and sufficient criterion is derived together with a simple geometrical interpretation. Our study shows that a Bell-diagonal state is steerable by two projective measurements iff it violates the Clauser-Horne-Shimony-Holt (CHSH) inequality, in sharp contrast with the strict hierarchy expected between steering and Bell nonlocality. We also introduce a steering measure and clarify its connections with concurrence and the volume of the steering ellipsoid. In particular, we determine the maximal concurrence and ellipsoid volume of Bell-diagonal states that are not steerable by two projective measurements. Finally, we explore the steerability of Bell-diagonal states under three projective measurements. A simple sufficient criterion is derived, which can detect the steerability of many states that are not steerable by two projective measurements. Our study offers valuable insight on steering of Bell-diagonal states as well as the connections between entanglement, steering and Bell nonlocality.
Far-field measurements of vortex beams interacting with nanoholes
Authors: Zambrana-Puyalto Xavier , Vidal Xavier , Fernandez-Corbaton Ivan , Molina-Terriza Gabriel
Published: February 2016

We measure the far-field intensity of vortex beams going through nanoholes. The process is analyzed in terms of helicity and total angular momentum. It is seen that the total angular momentum is preserved in the process and helicity is not. We compute the ratio between the two transmitted helicity components, γm,p. We observe that this ratio is highly dependent on the helicity (p) and the angular momentum (m) of the incident vortex beam in consideration. Due to the mirror symmetry of the nanoholes, we are able to relate the transmission properties of vortex beams with a certain helicity and angular momentum, with the ones with opposite helicity and angular momentum. Interestingly, vortex beams enhance the γm,p ratio as compared to those obtained by Gaussian beams.
The effect of DBP of carbon black on the dynamic self-assembly in a polymer melt
Authors: Li Xiaoyu , Deng Hua , Zhang Qin , Chen Feng , Fu Qiang
Published: February 2016

Three types of carbon black with different dibutyl phthalate (DBP) absorption have been used to study the electrical percolation behavior in thermoplastic polyurethane.
Immobilization of sulfur in microgels for lithium–sulfur battery
Authors: Chang Aiping , Wu Qingshi , Du Xue , Chen Shoumin , Shen Jing , Song Qiuyi , Xie Jianda , Wu Weitai
Published: February 2016

Immobilization of sulfur in microgels by using both chemical covalent-bonding and physical confinements leads to enhanced Li–S battery performance.
To enhance the capacity of Li-rich layered oxides by surface modification with metal–organic frameworks (MOFs) as cathodes for advanced lithium-ion batteries
Authors: Qiao Qi-Qi , Li Guo-Ran , Wang Yong-Long , Gao Xue-Ping
Published: February 2016

A Li-rich layered oxide, modified with Mn-based metal–organic frameworks (MOFs), shows a large discharge capacity, and good thermal stability as a cathode for lithium ion batteries.
LiNbO3 thin film ACP phase modulator for hybridly integrated ACP‐OPLL
Authors: Xu Longtao , Jin Shilei , Li Yifei
Published: February 2016

The first LiNbO3 thin film attenuated counter propagation (ACP) phase modulator is presented. The modulator demonstrates a Vπ of 2.5 V and a record 3 dB ACP modulator bandwidth of ∼1.8 GHz. It also demonstrated a lumped element response that is free of propagation delay. This device should be able to be integrated with external photodetectors to form a wideband ACP‐optical phase lock loop.
Dual‐polarised metal‐mountable UHF RFID tag antenna for polarisation diversity
Authors: Yang E.‐S. , Son H.‐W.
Published: February 2016

A polarisation diversity antenna for an ultra‐high‐frequency RFID tag is presented. The antenna consists of two dual‐planar inverted‐F antennas arranged in a cross‐configuration, and mountable on a metallic object. The antenna can work together with a linearly polarised reader antenna that has an arbitrary polarisation direction. The proposed tag antenna has a nearly uniform read range between 9.1 and 10.2 m, regardless of the polarisation direction of the reader's transmit field.
Thickness estimation of the subcutaneous fat using coaxial probe
Authors: Ramezani Mohammad Hossein , Nadimi Esmaeil S.
Published: February 2016

In this Letter, a non‐invasive method for thickness estimation of the subcutaneous fat layer of abdominal wall is presented by using a coaxial probe. Fat layer has the highest impact on the averaged attenuation parameter of the abdominal wall due to its high thickness and low permittivity. The abdominal wall is modelled as a multi‐layer medium and an analytical model for the probe is derived by calculation of its aperture admittance facing to this multi‐layer medium. The performance of this model is then validated by a numerical simulation using finite‐difference‐time‐domain (FDTD) analysis. Simulation results show the high impact of the probe dimension and fat layer thickness on the sensitivity of the measured permittivity. The authors further investigate this sensitivity by statistical analysis of the permittivity variations. Finally, measuring in different locations relative to the body surface is presented as a solution to estimate the fat layer thickness in the presence of uncertainty of model parameters.
Cyber attack mitigation for cyber–physical systems: hybrid system approach to controller design
Authors: Kwon Cheolhyeon , Hwang Inseok
Published: February 2016

This study considers robust controller design for cyber–physical systems (CPSs) subject to cyber attacks. While previous studies have investigated secure control by assuming specific attack strategies, in this study the authors propose a robust hybrid control scheme containing multiple sub‐controllers, each matched to a different type of cyber attack. A system using this control scheme is able to adapt its behaviour to various cyber attacks (including those which have not been specifically addressed in the sub‐controller designs) by switching sub‐controllers to achieve the best performance. They propose a method for designing the secure switching logic to counter possible cyber attacks and to mathematically verify the system's performance and stability as well. The performance of the proposed control scheme is demonstrated by the hybrid H2 –H∞ controller applied to a CPS subject to cyber attacks.
Distributed adaptive optimal regulation of uncertain large‐scale interconnected systems using hybrid Q‐learning approach
Authors: Narayanan Vignesh , Jagannathan Sarangapani
Published: February 2016

A novel hybrid Q‐learning algorithm is introduced for the design of a linear adaptive optimal regulator for a large‐scale interconnected system with event‐sampled inputs and state vector. Here, the time‐driven Q‐learning along with proposed iterative parameter learning updates are utilised within the event‐sampled instants to both improve efficiency of the optimal regulator and obtain a more generalised online Q‐learning framework. The network‐induced losses due to the presence of a communication network among the subsystems are considered along with the uncertain system dynamics. Stochastic model‐free Q‐learning and dynamic programming are utilised in the hybrid learning mode for the optimal regulator design. The asymptotic convergence of the system state vector and boundedness of the parameter vector is demonstrated using Lyapunov analysis. Further, when the regression vector of the Q‐function estimator satisfies the persistency of excitation condition, the Q‐function parameters converge to the expected target values. The analytical design is evaluated using numerical examples via simulation. The net result is the design of a data‐driven event‐sampled adaptive optimal regulator for an uncertain large‐scale interconnected system.
Physics‐based model of LPT CSTBT including MOS‐side two‐dimensional effects
Authors: Fu Guicui , Xue Peng
Published: February 2016

In this study, a physics‐based model for light punch through (LPT) carrier stored trench bipolar transistor (CSTBT) is developed. The model is based on the Fourier series solution of ambipolar diffusion equation implemented in MATLAB and Simulink. In the model, the MOS‐side two‐dimensional (2D) effects resulting from trench gate and carrier storage layer are studied analytically. Assuming high‐level injection in LPT buffer layer, the model also describes the carrier transport, redistribution and recombination in the buffer layer in details. The static and transient experiments for a commercial CSTBT are used to validate the presented model. The simulation results are compared with experiment results and good agreement is obtained.
Low‐cost switched capacitor charge equaliser with cancellation mechanism of alternating current
Authors: Hua Chih‐Chiang , Chuang Chih‐Wei , Fang Yi‐Hsiung
Published: February 2016

A low‐cost switched capacitor charge equaliser with cancellation mechanism of alternating current for electric vehicles is proposed in this study. Among various charge equalisers, the switched capacitor type equaliser is popular due to its simplicity, small volume and low cost. However, the cycle life of battery will be reduced by unnecessary energy transfer since an alternating current flows through the battery without energy change. Hence, a cancellation mechanism of alternating current is presented to deliver energy directly from the source battery to the target battery, which avoids the unnecessary charging and discharging for the battery without energy variations. A low‐voltage H‐bridge drive integrated circuit (IC) is used to reduce the cost, size and complexity of the proposed equaliser. The circuit topology and operation analysis of the proposed charge equaliser are described in detail. Finally, the experimental results verify the effectiveness and performance of the proposed charge equaliser.
Comparison of power electronics lifetime between vertical‐ and horizontal‐axis wind turbines
Authors: Parker Max Alexander , Soraghan Conaill , Giles Alex
Published: February 2016

A comparison has been made of the power electronics lifetime for 5MW horizontal‐ and vertical‐axis wind turbines, based on dynamic models supplied with generated wind speed time series. Both two‐ and three‐bladed stall‐regulated H‐rotor vertical‐axis turbines were modelled, with several different control parameters. Vertical‐axis turbines are likely to lead to a shorter power electronics lifetime as the aerodynamic torque varies with rotor azimuth, leading to a cyclic generator torque, and increased thermal cycling in the power electronics. An electro‐thermal model of a low‐voltage converter was created, and used to calculate the switching device temperatures based on the generator torque and speed time series from the turbine model. An empirical lifetime model and rainflow‐counting algorithm were used to calculate the lifetime, and this was repeated at different average wind speeds to determine the overall lifetime. The vertical‐axis turbine was found to have a lower power electronics lifetime than the horizontal‐axis, or require a larger number of parallel switching devices to achieve the same lifetime, although this was lessened by running the turbine with a more relaxed speed control, allowing the rotor inertia to partially absorb the aerodynamic torque ripple.
Dorsal Intramedullary Lipoma without Spinal Dysraphism: A Rare Case Report and Review of Literature
Authors: Baishya Basanta Kumar , Agarwal Sushant , Hussain Zakir , Dutta Deep
Published: February 2016

Study Design Case report.

Objective The study aims to report a rare case of dorsal intramedullary lipoma, its management, and outcome.

Background We are reporting the rare case of a 23-year-old man with dorsal intramedullary lipoma without spinal dysraphism. The clinical presentation, diagnosis, and management are discussed with relevant review of literature.

Conclusion Intramedullary cord lipoma without spinal dysraphism can be a cause of myelopathy, and proper diagnosis with MRI and subtotal excision preserving the vital cord parenchyma should be the goal, which can give a better outcome.
Management of a Complex Basilar Invagination Case with Multiple Revision Surgeries – Case Report
Authors: Miranda Carlos , Torres Hélio , Barreiro Guilherme , Joaquim Andrei , Tedeschi Helder
Published: February 2016

We describe a Basilar Invagination (BI) case with craniocervical instability and many previous failure surgeries and poor wound coverage. The patient had been submitted to a large posterior fossa craniectomy (which greatly limited the availability of an adequate area for bone fixation) and showed a poor quality of the surgical wound in the posterior craniocervical region. We performed an occipito-cervical fixation, using the bone overlying the torculla as a point of cranial fixation. Craniocervical realignment was achieved by the use of distractive maneuvers with occipital rods, followed by coverage of the hardware via a pedicled longitudinal trapeze myocutaneous flap. We used local ribs removed from the region where the myocutaneous flap was harvested as autologous bone grafts for craniocervical fusion. Post-operatively, the patient was placed in a halo-vest for three months. The patient improved substantially after the procedure, recovered some muscular strength and experienced total relief of her pain. We hereby discuss the surgical strategy used for treating this complex case in details, with illustrative pictures.
Highly efficient and stable ultraviolet photocathode based on nanodiamond particles
Authors: Velardi L. , Valentini A. , Cicala G.
Published: February 2016

Nanodiamond (ND) layers on silicon substrate are deposited by the pulsed spray technique starting from nanoparticles of about 250 nm dispersed in 1,2-dichloroethane solvent. The aim of this letter is to investigate the quantum efficiency (QE) of photocathodes based on ND particles in the vacuum ultraviolet spectral range. Various ND layers are examined employing as-received and hydrogenated nanoparticles. As expected, the hydrogen plasma treatment improves strongly the photoemission of the layer giving a QE of 22% at 146 nm. Indeed, this efficiency value is achieved only if the particles are treated in H2 microwave plasma before the growth of the sprayed layer rather than to hydrogenate the already formed one. These QE values are higher than those of photocathodes based on plasma chemical vapor deposition diamond films, but with the advantage of being much stable, too. The highest QE values are explained to be due to the intrinsic chemical and structural features of utilized ND particles.
Living (and reproducing) on the edge: reproductive phenology is impacted by rainfall and canopy decline in a Mediterranean eucalypt
Authors: Moore T. L. , Ruthrof K. X. , Craig M. D. , Valentine L. E. , Hardy G. E. St J. , Fleming P. A.
Published: February 2016

Many of the worlds’ forests and woodlands are currently showing symptoms of declining condition due to a range of factors, including changing climatic conditions, drought and insect herbivory. Altered abiotic and biotic conditions can influence the condition of trees that can, in turn, affect tree reproductive cycles. However, the potential impact of tree decline on reproductive cycles has rarely been examined. This study investigated the influence of canopy condition on the reproductive cycle of Eucalyptus wandoo Blakely in south-western Australia. Canopy and seed trap monitoring were used to assess bud production, flowering, fruiting and seed fall over 12 months at 24 sites across two locations (Dryandra Woodland and Wandoo Conservation Park). Time since last fire, rainfall, ambient temperatures and the condition of individual trees were recorded. We found that bud production, flowering and fruiting was correlated with tree condition: healthier trees were generally associated with higher reproductive effort. Time since last fire was also strongly related to the reproductive efforts at both locations. Declining annual rainfall and increased temperatures also impact on reproduction, made evident by the aborted flowering in Dryandra Woodland. Decline in tree condition, coupled with changes in climate, have major implications for flowering phenology of this species and have the potential to alter reproductive effort, recruitment and future population dynamics. Consideration of these issues should be incorporated into the conservation management of E. wandoo and similar Eucalypt species.
Emergency Department Presentation and Mortality Rate Due to Overdose: A Retrospective Cohort Study on Nonfatal Overdoses
Authors: Pavarin Raimondo Maria , Berardi Domenico , Gambini Daniele
Published: February 2016

Background: The aims of this retrospective cohort study are to describe the presentation characteristics for nonfatal overdose-related complaints at the emergency departments (EDs) of the metropolitan area of Bologna (northern Italy), to estimate the subsequent risk of mortality by overdose, and to identify the profiles of the subjects most at risk. Methods: Records of patients admitted to 10 EDs for overdose between January 2004 and December 2012 were retrospectively evaluated. The International Classification of Diseases was used to ascertain the cause of death. Results: A total of 294 episodes of overdose involving 218 individuals were identified. The total time at risk was 1048 person-years (PY). The mortality rate for all causes was 35.48 per 1000 PY for males and 20.61 per 1000 PY for females. The mortality rate for overdose was 16.6 per 1000 PY for males and 13.74 per 1000 PY for females. In the multivariate regression analysis, the time from first ED overdose access (less than 1 year risk ratio [RR]: 7.07, 95% confidence interval [CI]: 5.32–9.39) was significantly associated with death by overdose. Males, subjects aged >30 years at presentation, patients who refused ED treatment, and those having previously contacted mental health services showed an increased mortality risk due to overdose. Conclusions: Experiencing a nonfatal overdose within the past 12 months increases the risk of mortality compared with an overdose more than 12 months earlier. Nonfatal overdose patients presenting to an ED form a specific target for prevention projects.
The effect of mate removal on dawn singing behaviour in male pied bush chats
Authors: Sethi Vinaya Kumar , Bhatt Dinesh , Kumar Amit
Published: February 2016

To determine the influence of pairing status on dawn singing behaviour in pied bush chats Saxicola caprata, we conducted mate removal experiments across eight territories. The experiment was divided into three stages: pre-removal (pairs were present on their respective territories), removal (females were experimentally removed), and returned (females were released into the focal pairs’ territories). Dawn bout length, song rate, song complexity, percentage performance time, song perch height, and distance of singing location to territory boundary were measured for each male during each experimental stage. We did not find an effect of mate removal on any dawn song characteristics of male pied bush chats suggesting that the presence or absence of a mate does not influence male dawn singing behaviour. Our findings further suggest that males use dawn chorus to mediate social relationships with neighbouring males to proclaim an established territory.
Cutting the Gordian knot: Complex signaling in African cichlids is more than multimodal
Authors: Van Staaden Moira J. , Smith Adam R.
Published: February 2016

The active transmission of information from sender to receiver is a fundamental component of communication, and is therefore a primary facet in evolutionary models of sexual selection. Research in several systems has underlined the importance of multiple sensory modalities in courtship signals. However, we still tend to think of individuals as having a relatively static signal in consecutive communicative events. While this may be true for certain traits such as body size or coloration, behaviorally modulated signals can quickly violate this assumption. In this work, we explore how intraspecific variation may be an important component of interspecific signal divergence using cichlid fishes from Lake Malawi. Behavioral analyses were made using six species of Malawian cichlids from two divergent genera. While interspecific differences were found between congeners based on species-level analyses of both acoustic and audiovisual signals, intraspecific variation was of a similar magnitude. Specifically, individual fishes were found to possess highly plastic signal repertoires. This finding was ubiquitous across all species and resulted in a great deal of overlap between heterospecific individuals, despite statistically distinct species means. These results demonstrate that some aspects of courtship in Malawian cichlids are more plastic than previously proposed, and that studies must account for signal variability within individuals. We propose here that behavioral variability in signaling is important in determining the communication landscape on which signals are perceived. We review potential complexity deriving from multimodal signaling, discuss the sources for such lability, and suggest ways in which this issue may be approached experimentally.
Effect of losing a fight on later agonistic behavior toward unfamiliar conspecifics in male Syrian hamsters
Authors: Delbarco-Trillo Javier , Johnston Robert E.
Published: February 2016

In many species, agonistic interactions result in social relationships that are stable over time. In Syrian hamsters, two unfamiliar males that are placed together will fight vigorously and a clear winner/loser relationship is usually established. In subsequent interactions, the loser will flee soon after detecting the familiar winner. Here we tested the hypothesis that losing a fight with a conspecific will affect future agonistic interactions not only toward that individual (i.e., the familiar winner) but also toward unfamiliar conspecifics. To test this hypothesis we paired two Syrian hamster males in three trials on one day in which the loser had the opportunity to escape the winner. The next day the loser was paired with an unfamiliar male, also for three trials. If he lost again, he was tested on a third day with a third unfamiliar male. Subjects were those males that were losers on all three days. The latency to escape on the first trial on Days 2 and 3 was significantly shorter than on the first trial on Day 1, indicating that losing against the first male affected the response toward unfamiliar males. However, the latency to escape on the first trial on Days 2 and 3 was significantly longer than that on the third trial on the preceding day, indicating that a loser treats unfamiliar males differently than a familiar winner. These results suggest that a defeat during an interaction with one male affects later agonistic behavior towards other, unfamiliar males.
Prime waterfront real estate: Apple snails choose wild taro for oviposition sites
Authors: Kyle Colin H. , Kropf Alexis W. , Burks Romi L.
Published: February 2016

While difficult to prevent introductions, scientific research can help guide control efforts of exotic, invasive species. South American island apple snails Pomacea insularum have quickly spread across the United States Gulf Coast and few control measures exist to delay their spread. Usually occupying cryptic benthic habitats, female apple snails crawl out of the water to deposit large, bright pink egg clutches on emergent objects. To help identify the most likely place to find and remove clutches, we conducted four lab experiments to investigate what specific object qualities (i.e. material; shape and height; plant species; natural and artificial) attracted P. insularum females to lay clutches. In our fourth experiment, we specifically examined the relationship between female size and reproductive output. To further understand reproductive output, we quantified experimental clutch characteristics (height above water, dimensions, mass, approximate volume, number of eggs, hatching efficiency). Pomacea insu-larum females laid more clutches on plant material, chose round over flat surfaces and failed to differentiate between tall and short structures. In comparison to a common native plant in the eastern US, Pontederia cordata, snails clearly preferred to lay clutches on a widely distributed exotic, invasive plant (wild taro, Colocasia esculenta). Unexpectedly, smaller snails showed higher overall total fecundity as well as more eggs per clutch than larger snails. Therefore, hand removal efforts of large females may not be enough to slow down clutch production. Collectively, our results indicate that conservationists and managers should search emergent plants for P. insularum clutches carefully to guard against established populations.
Taxonomic confusion of two tramp ant species: Iridomyrmex anceps and Ochetellus glaber are really species complexes
Authors: Hoffmann Benjamin D. , Andersen Alan N. , Zhang Xiang
Published: February 2016

Many invasive invertebrates belong to unresolved species complexes, and have a history of misidentification and inappropriate management. Here we detail confusion surrounding the taxonomy and identification of two dolichoderine ant species, Iridomyrmex anceps Roger and Ochetellus glaber Mayr, which are commonly cited in the literature as having been spread widely by human commerce. We provide morphometric data and images strongly suggesting that these two “species” are instead complexes of species that are likely native to many regions where they are purportedly introduced. We take particular interest in the status of species referred to as I. anceps and O. glaber in China, as this is the most northerly distribution of both genera. We conclude by suggesting that many identifications of both species are likely to be unreliable, and we recommend against any management action aimed at controlling these species under the assumption that they are exotic.
An empirical movement model for sixgill sharks in Puget Sound: Combining observed and unobserved behavior
Authors: Levin Phillip S. , Horne Peter , Andrews Kelly S. , Williams Greg
Published: February 2016

Understanding the movement of animals is fundamental to population and community ecology. Historically, it has been difficult to quantify movement patterns of most fishes, but technological advances in acoustic telemetry have increased our abilities to monitor their movement. In this study, we combined small-scale active acoustic tracking with large-scale passive acoustic monitoring to develop an empirical movement model for sixgill sharks in Puget Sound, WA, USA. We began by testing whether a correlated random walk model described the daily movement of sixgills; however, the model failed to capture home-ranging behavior. We added this behavior and used the resultant model (a biased random walk model) to determine whether daily movement patterns are able to explain large-scale seasonal movement. The daily model did not explain the larger-scale patterns of movement observed in the passive monitoring data. In order to create the large-scale patterns, sixgills must have performed behaviors (large, fast directed movements) that were unobserved during small-scale active tracking. In addition, seasonal shifts in location were not captured by the daily model. We added these ‘unobserved’ behaviors to the model and were able to capture large-scale seasonal movement of sixgill sharks over 150 days. The development of empirical models of movement allows researchers to develop hypotheses and test mechanisms responsible for a species movement behavior and spatial distribution. This knowledge will increase our ability to successfully manage species of concern.
Why do fish school?
Authors: Larsson Matz
Published: February 2016

Synchronized movements (schooling) emit complex and overlapping sound and pressure curves that might confuse the inner ear and lateral line organ (LLO) of a predator. Moreover, prey-fish moving close to each other may blur the electro-sensory perception of predators. The aim of this review is to explore mechanisms associated with synchronous swimming that may have contributed to increased adaptation and as a consequence may have influenced the evolution of schooling. The evolutionary development of the inner ear and the LLO increased the capacity to detect potential prey, possibly leading to an increased potential for cannibalism in the shoal, but also helped small fish to avoid joining larger fish, resulting in size homogeneity and, accordingly, an increased capacity for moving in synchrony. Water-movements and incidental sound produced as by-product of locomotion (ISOL) may provide fish with potentially useful information during swimming, such as neighbour body-size, speed, and location. When many fish move close to one another ISOL will be energetic and complex. Quiet intervals will be few. Fish moving in synchrony will have the capacity to discontinue movements simultaneously, providing relatively quiet intervals to allow the reception of potentially critical environmental signals. Besides, synchronized movements may facilitate auditory grouping of ISOL. Turning preference bias, well-functioning sense organs, good health, and skillful motor performance might be important to achieving an appropriate distance to school neighbors and aid the individual fish in reducing time spent in the comparatively less safe school periphery. Turning preferences in ancestral fish shoals might have helped fish to maintain groups and stay in formation, reinforcing aforementioned predator confusion mechanisms, which possibly played a role in the lateralization of the vertebrate brain.
Spawning ascent durations of pelagic spawning reef fishes
Authors: Habrun Caroline A. , Sancho Gorka
Published: February 2016

Predation risks have been hypothesized to influence spawning behaviors of coral reef fishes that broadcast gametes pelagically. The duration of spawning ascents of 13 species were measured from video footage at a single spawning site for multiple coral reef fishes to investigate if this behavior was influenced by varying risks of predation. Fishes that spawned in pairs had ascents of longer duration than group-spawning species. Duration of spawning ascents did not vary between fishes spawning at daytime and dusk, nor between group-spawning species with specific anti-predatory morphological adaptations. These results indicate that risk of predation may not significantly influence the duration of spawning ascents of pair spawning reef fishes at our study site, while group-spawning behaviors are influenced by predation. Avoidance of egg predation by benthic organisms and female mate choice are more likely to influence the pelagic spawning behaviors of all fishes observed.
Tail loss affects fecundity but not offspring traits in the Chinese skink Eumeces chinensis
Authors: Lu Hongliang , Gao Jianfang , Ma Xiaohao , Lin Zhihua , Ji Xiang
Published: February 2016

We used the Chinese skink Eumeces chinensis as a model animal to study the effects of tail loss on reproductive investment and offspring traits. A total of 147 wild-captured adult females were divided into four groups according to their tail conditions. Tail breaks occurred most frequently in the proximal portion of the tail and least frequently in the distal portion, with the middle portion in between. This finding suggests that tail breaks occurring in nature often entails substantial energetic costs in E. chinensis where the tail is a major site of energy storage. The proportion of females that laid eggs was higher in females with intact or completely regenerated tails than in those with broken tails. Following whole-tail autotomy, the clutch size was reduced by 17%, and the clutch mass was reduced by 14%. Females undergoing substantial tail autotomy reduced reproductive investment, and they did so by reducing the number but not the size of eggs produced. None of the egg and hatchling traits was affected by tail loss. Comparing our data with those reported for other oviparous and viviparous skinks allows us to draw two general conclusions: one is that fecundity (clutch or litter size) is affected by tail loss in all species so far studied, whereas offspring size is affected by tail loss in some species, but not in others; the other is that the reduction in fecundity following tail loss is more evident in species lacking abdominal fat bodies [Current Zoology 58 (2): 228–235, 2012].
Phenotype manipulation influences microhabitat choice in pygmy grasshoppers
Authors: Wennersten Lena , Karpestam Einat , Forsman Anders
Published: February 2016

The matching habitat choice hypothesis posits that individuals actively choose those microhabitats that best match their specific phenotype to maximize fitness. Despite the profound implications, matching habitat choice has not been unequivocally demonstrated. We conducted two experiments to examine the impact of pigmentation pattern in the color polymorphic pygmy grasshopper Tetrix subulata on habitat choice in a laboratory thermal mosaic arena. We found no behavioral differences in the thermal mosaic among pygmy grasshoppers belonging to either pale, intermediate or dark natural color morphs. However, after manipulating the grasshoppers’ phenotype, the utilization through time of warmer and colder parts of the arena was different for black-painted and white-painted individuals. White-painted individuals used warmer parts of the arena, at least during the initial stage of the experiment. We conclude that microhabitat choice represents a form of behavioural plasticity. Thus, even if the choice itself is flexible and not genetically determined, it can still lead to spatial genetic structure in the population because the phenotypes themselves may be genetically mediated.