bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electronic Structure and Ferromagnetism Modulation in Cu/Cu2O Interface: Impact of Interfacial Cu Vacancy and Its Diffusion
Authors: Li Hao-Bo , Wang Weichao , Xie Xinjian , Cheng Yahui , Zhang Zhaofu , Dong Hong , Zheng Rongkun , Wang Wei-Hua , Lu Feng , Liu Hui 
Published: October 2015

AbstractCu/Cu2O composite structures have been discovered to show sizable ferromagnetism (FM) with the potential applications in spintronic devices. To date, there is no consensus on the FM origin in Cu/Cu2O systems. Here, first principles calculations are performed on the interface structure to explore the microscopic mechanism of the FM. It is found that only the Cu vacancy (VCu) adjacent to the outermost Cu2O layer induces a considerable magnetic moment, mostly contributed by 2p orbitals of the nearest-neighbor oxygen atom (ONN) with two dangling bonds and 3d orbitals of the Cu atoms bonding with the ONN. Meanwhile, the charge transfer from Cu to Cu2O creates higher density of states at the Fermi level and subsequently leads to the spontaneous FM. Furthermore, the FM could be modulated by the amount of interfacial VCu, governed by the interfacial Cu diffusion with a moderate energy barrier (~1.2 eV). These findings provide insights into the FM mechanism and tuning the FM via interfacial cation diffusion in the Cu/Cu2O contact.
De novo KCNB1 mutations in infantile epilepsy inhibit repetitive neuronal firing
Authors: Saitsu Hirotomo , Akita Tenpei , Tohyama Jun , Goldberg-Stern Hadassa , Kobayashi Yu , Cohen Roni , Kato Mitsuhiro , Ohba Chihiro , Miyatake Satoko , Tsurusaki Yoshinori , Nakashima Mitsuko , Miyake Noriko , Fukuda Atsuo , Matsumoto Naomichi 
Published: October 2015

AbstractThe voltage-gated Kv2.1 potassium channel encoded by KCNB1 produces the major delayed rectifier potassium current in pyramidal neurons. Recently, de novo heterozygous missense KCNB1 mutations have been identified in three patients with epileptic encephalopathy and a patient with neurodevelopmental disorder. However, the frequency of KCNB1 mutations in infantile epileptic patients and their effects on neuronal activity are yet unknown. We searched whole exome sequencing data of a total of 437 patients with infantile epilepsy and found novel de novo heterozygous missense KCNB1 mutations in two patients showing psychomotor developmental delay and severe infantile generalized seizures with high-amplitude spike-and-wave electroencephalogram discharges. The mutation located in the channel voltage sensor (p.R306C) disrupted sensitivity and cooperativity of the sensor, while the mutation in the channel pore domain (p.G401R) selectively abolished endogenous Kv2 currents in transfected pyramidal neurons, indicating a dominant-negative effect. Both mutants inhibited repetitive neuronal firing through preventing production of deep interspike voltages. Thus KCNB1 mutations can be a rare genetic cause of infantile epilepsy and insufficient firing of pyramidal neurons would disturb both development and stability of neuronal circuits, leading to the disease phenotypes.
The Impact of Environmental Fluctuations on Evolutionary Fitness Functions
Authors: Melbinger Anna , Vergassola Massimo 
Published: October 2015

AbstractThe concept of fitness as a measure for a species’ success in natural selection is central to the theory of evolution. We here investigate how reproduction rates which are not constant but vary in response to environmental fluctuations, influence a species’ prosperity and thereby its fitness. Interestingly, we find that not only larger growth rates but also reduced sensitivities to environmental changes substantially increase the fitness. Thereby, depending on the noise level of the environment, it might be an evolutionary successful strategy to minimize this sensitivity rather than to optimize the reproduction speed. Also for neutral evolution, where species with exactly the same properties compete, variability in the growth rates plays a crucial role. The time for one species to fixate is strongly reduced in the presence of environmental noise. Hence, environmental fluctuations constitute a possible explanation for effective population sizes inferred from genetic data that often are much smaller than the census population size.
A scanning acoustic microscope discriminates cancer cells in fluid
Authors: Miura Katsutoshi , Yamamoto Seiji 
Published: October 2015

AbstractScanning acoustic microscopy (SAM) discriminates lesions in sections by assessing the speed of sound (SOS) or attenuation of sound (AOS) through tissues within a few minutes without staining; however, its clinical use in cytological diagnosis is unknown. We applied a thin layer preparation method to observe benign and malignant effusions using SAM. Although SAM is inferior in detecting nuclear features than light microscopy, it can differentiate malignant from benign cells using the higher SOS and AOS values and large irregular cell clusters that are typical features of carcinomas. Moreover, each single malignant cell exhibits characteristic cytoplasmic features such as a large size, irregular borders and secretory or cytoskeletal content. By adjusting the observation range, malignant cells are differentiated from benign cells easily using SAM. Subtle changes in the functional and structural heterogeneity of tumour cells were pursuable with a different digital data of SAM. SAM can be a useful tool for screening malignant cells in effusions before light microscopic observation. Higher AOS values in malignant cells compared with those of benign cells support the feasibility of a novel sonodynamic therapy for malignant effusions.
Human Mitochondrial DNA-Protein Complexes Attach to a Cholesterol-Rich Membrane Structure
Authors: Gerhold Joachim M. , Cansiz-Arda Şirin , Lõhmus Madis , Engberg Oskar , Reyes Aurelio , van Rennes Helga , Sanz Alberto , Holt Ian J. , Cooper Helen M. , Spelbrink Johannes N. 
Published: October 2015

AbstractThe helicase Twinkle is indispensable for mtDNA replication in nucleoids. Previously, we showed that Twinkle is tightly membrane-associated even in the absence of mtDNA, which suggests that Twinkle is part of a membrane-attached replication platform. Here we show that this platform is a cholesterol-rich membrane structure. We fractionated mitochondrial membrane preparations on flotation gradients and show that membrane-associated nucleoids accumulate at the top of the gradient. This fraction was shown to be highly enriched in cholesterol, a lipid that is otherwise low abundant in mitochondria. In contrast, more common mitochondrial lipids and abundant inner-membrane associated proteins concentrated in the bottom-half of these gradients. Gene silencing of ATAD3, a protein with proposed functions related to nucleoid and mitochondrial cholesterol homeostasis, modified the distribution of cholesterol and nucleoids in the gradient in an identical fashion. Both cholesterol and ATAD3 were previously shown to be enriched in ER-mitochondrial junctions and we detect nucleoid components in biochemical isolates of these structures. Our data suggest an uncommon membrane composition that accommodates platforms for replicating mtDNA and reconcile apparently disparate functions of ATAD3. We suggest that mtDNA replication platforms are organized in connection with ER-mitochondrial junctions, facilitated by a specialized membrane architecture involving mitochondrial cholesterol.
Effect of Treatment on Body Fluid in Patients with Unilateral Aldosterone Producing Adenoma: Adrenalectomy versus Spironolactone
Authors: Wu Che-Hsiung , Yang Ya-Wen , Hung Szu-Chun , Tsai Yao-Chou , Hu Ya-Hui , Lin Yen-Hung , Chu Tzong-Shinn , Wu Kwan-Dun , Wu Vin-Cent 
Published: October 2015

AbstractAldosterone affects fluid retention in the body by affecting how much salt and water that the kidney retains or excretes. There is limited information about the effect of prolonged aldosterone excess and treatment on body fluid in primary aldosteronism (PA) patients. In this study, body composition changes of 41 PA patients with unilateral aldosterone producing adenoma (APA) were assessed by a bio-impedance spectroscopy device. Patients with APA receiving adrenalectomy, as compared with those treated with spironolactone, had significantly lower relative overhydration (OH) and urine albumin excretion and significantly higher urine sodium excretion four weeks after treatment. These differences dissipated 12 weeks after the initial treatment. Independent factors to predict decreased relative OH four weeks after treatment were male patients and patients who experienced adrenalectomy. Patients who underwent adrenaelctomy had significantly decreased TNF-α and increased serum potassium level when compared to patients treated with spironolactone 4 and 12 weeks after treatment. In this pilot study, we found that adrenalectomy leads to an earlier increase in renal sodium excretion and decreases in body fluid content, TNF-α and urine albumin excretion. Adrenalectomy yields a therapeutic effect more rapidly, which has been shown to ameliorate overhydration in PA patients.
Impaired climbing and flight behaviour in Drosophila melanogaster following carbon dioxide anaesthesia
Authors: Bartholomew Nathan R. , Burdett Jacob M. , VandenBrooks John M. , Quinlan Michael C. , Call Gerald B. 
Published: October 2015

AbstractLaboratories that study Drosophila melanogaster or other insects commonly use carbon dioxide (CO2) anaesthesia for sorting or other work. Unfortunately, the use of CO2 has potential unwanted physiological effects, including altered respiratory and muscle physiology, which impact motor function behaviours. The effects of CO2 at different levels and exposure times were examined on the subsequent recovery of motor function as assessed by climbing and flight assays. With as little as a five minute exposure to 100% CO2, D. melanogaster exhibited climbing deficits up to 24 hours after exposure. Any exposure length over five minutes produced climbing deficits that lasted for days. Flight behaviour was also impaired following CO2 exposure. Overall, there was a positive correlation between CO2 exposure length and recovery time for both behaviours. Furthermore, exposure to as little as 65% CO2 affected the motor capability of D. melanogaster. These negative effects are due to both a CO2-specific mechanism and an anoxic effect. These results indicate a heretofore unconsidered impact of CO2 anaesthesia on subsequent behavioural tests revealing the importance of monitoring and accounting for CO2 exposure when performing physiological or behavioural studies in insects.
Bv8/prokineticin 2 is involved in Aβ-induced neurotoxicity
Authors: Severini Cinzia , Lattanzi Roberta , Maftei Daniela , Marconi Veronica , Ciotti Maria Teresa , Petrocchi Passeri Pamela , Florenzano Fulvio , Del Duca Ester , Caioli Silvia , Zona Cristina , Balboni Gianfranco , Salvadori Severo , Nisticò Robert , Negri Lucia 
Published: October 2015

AbstractBv8/Prokineticin 2 (PROK2) is a bioactive peptide initially discovered as a regulator of gastrointestinal motility. Among multiple biological roles demonstrated for PROK2, it was recently established that PROK2 is an insult-inducible endangering mediator for cerebral damage. Aim of the present study was to evaluate the PROK2 and its receptors’ potential involvement in amyloid beta (Aβ) neurotoxicity, a hallmark of Alzheimer’s disease (AD) and various forms of traumatic brain injury (TBI). Analyzing primary cortical cultures (CNs) and cortex and hippocampus from Aβ treated rats, we found that PROK2 and its receptors PKR1 and PKR2 mRNA are up-regulated by Aβ, suggesting their potential involvement in AD. Hence we evaluated if impairing the prokineticin system activation might have protective effect against neuronal death induced by Aβ. We found that a PKR antagonist concentration-dependently protects CNs against Aβ1–42-induced neurotoxicity, by reducing the Aβ-induced PROK2 neuronal up-regulation. Moreover, the antagonist completely rescued LTP impairment in hippocampal slices from 6 month-old Tg2576 AD mice without affecting basal synaptic transmission and paired pulse-facilitation paradigms. These results indicate that PROK2 plays a role in cerebral amyloidosis and that PROK2 antagonists may represent a new approach for ameliorating the defining pathology of AD.
Transient unidirectional energy flow and diode-like phenomenon induced by non-Markovian environments
Authors: Jing Jun , Segal Dvira , Li Baowen , Wu Lian-Ao 
Published: October 2015

AbstractRelying on an exact time evolution scheme, we identify a novel transient energy transfer phenomenon in an exactly-solvable quantum microscopic model consisting of a three-level system coupled to two non-Markovian zero-temperature bosonic baths through two separable quantum channels. The dynamics of this model can be solved exactly using the quantum-state-diffusion equation formalism, demonstrating finite intervals of unidirectional energy flow across the system, typically, from the non-Markovian environment towards the more Markovian bath. Furthermore, when introducing a spatial asymmetry into the system, an analogue of the rectification effect is realized. In the long time limit, the dynamics arrives at a stationary state and the effects recede. Understanding temporal characteristics of directional energy flow will aid in designing microscopic energy transfer devices.
Transient dual-energy lasing in a semiconductor microcavity
Authors: Hsu Feng-Kuo , Xie Wei , Lee Yi-Shan , Lin Sheng-Di , Lai Chih Wei 
Published: October 2015

AbstractWe demonstrate sequential lasing at two well-separated energies in a highly photoexcited planar microcavity at room temperature. Two spatially overlapped lasing states with distinct polarization properties appear at energies more than 5 meV apart. Under a circularly polarized nonresonant 2 ps pulse excitation, a sub-10-ps transient circularly polarized high-energy (HE) state emerges within 10 ps after the pulse excitation. This HE state is followed by a pulsed state that lasts for 20–50 ps at a low energy (LE) state. The HE state is highly circularly polarized as a result of a spin-preserving stimulated process, while the LE state shows a significantly reduced circular polarization because of a diminishing spin imbalance.
Multi-phase functionalization of titanium for enhanced photon absorption in the vis-NIR region
Authors: Thakur Pooja , Tan Bo , Venkatakrishnan Krishnan 
Published: October 2015

AbstractInadequate absorption of Near Infrared (NIR) photons by conventional silicon solar cells has been a major stumbling block towards the attainment of a high efficiency “full spectrum” solar cell. An effective enhancement in the absorption of such photons is desired as they account for a considerable portion of the tappable solar energy. In this work, we report a remarkable gain observed in the absorption of photons in the near infrared and visible region (400 nm–1000 nm) by a novel multi-phased oxide of titanium. Synthesised via a single step ultra-fast laser pulse interaction with pure titanium, characterisation studies have identified this oxide of titanium to be multi-phased and composed of Ti3O, (TiO.716)3.76 and TiO2 (rutile). Computed to have an average band gap value of 2.39 eV, this ultrafast laser induced multi-phased titanium oxide has especially exhibited steady absorption capability in the NIR range of 750–1000 nm, which to the best of our knowledge, was never reported before. The unique NIR absorption properties of the laser functionalised titanium coupled with the simplicity and versatility of the ultrafast laser interaction process involved thereby provides tremendous potential towards the photon sensitization of titanium and thereafter for the inception of a “full spectrum” solar device.
Novel method for immunofluorescence staining of mammalian eggs using non-contact alternating-current electric-field mixing of microdroplets
Authors: Shirasawa Hiromitsu , Kumagai Jin , Sato Emiko , Kabashima Katsuya , Kumazawa Yukiyo , Sato Wataru , Miura Hiroshi , Nakamura Ryuta , Nanjo Hiroshi , Minamiya Yoshihiro , Akagami Yoichi , Terada Yukihiro 
Published: October 2015

AbstractRecently, a new technique was developed for non-catalytically mixing microdroplets. In this method, an alternating-current (AC) electric field is used to promote the antigen–antibody reaction within the microdroplet. Previously, this technique has only been applied to histological examinations of flat structures, such as surgical specimens. In this study, we applied this technique for the first time to immunofluorescence staining of three-dimensional structures, specifically, mammalian eggs. We diluted an antibody against microtubules from 1:1,000 to 1:16,000 and compared the chromatic degree and extent of fading across dilutions. In addition, we varied the frequency of AC electric-field mixing from 5 Hz to 46 Hz and evaluated the effect on microtubule staining. Microtubules were more strongly stained after AC electric-field mixing for only 5 minutes, even when the concentration of primary antibody was 10 times lower than in conventional methods. AC electric-field mixing also alleviated microtubule fading. At all frequencies tested, AC electric-field mixing resulted in stronger microtubule staining than in controls. There was no clear difference in a microtubule staining between frequencies. These results suggest that the novel method could reduce antibody consumption and shorten immunofluorescence staining time.
Giant electro-optic effect in Ge/SiGe coupled quantum wells
Authors: Frigerio Jacopo , Vakarin Vladyslav , Chaisakul Papichaya , Ferretto Marcello , Chrastina Daniel , Le Roux Xavier , Vivien Laurent , Isella Giovanni , Marris-Morini Delphine 
Published: October 2015

AbstractSilicon-based photonics is now considered as the photonic platform for the next generation of on-chip communications. However, the development of compact and low power consumption optical modulators is still challenging. Here we report a giant electro-optic effect in Ge/SiGe coupled quantum wells. This promising effect is based on an anomalous quantum-confined Stark effect due to the separate confinement of electrons and holes in the Ge/SiGe coupled quantum wells. This phenomenon can be exploited to strongly enhance optical modulator performance with respect to the standard approaches developed so far in silicon photonics. We have measured a refractive index variation up to 2.3 × 10−3 under a bias voltage of 1.5 V, with an associated modulation efficiency VπLπ of 0.046 V cm. This demonstration paves the way for the development of efficient and high-speed phase modulators based on the Ge/SiGe material system.
Maximising power‐transfer efficiency in low‐power DC–DC converters
Authors: Damodaran Prabha R. , Rincón‐Mora G.A. 
Published: October 2015

Wireless microsensors can add energy‐ and life‐saving intelligence to remote and inaccessible places like factories, hospitals and so on. For this, they normally house sensors, data converters, digital processors, memory, transmitters, and power supplies. Although some of these functions can demand milliwatts at a time, the events monitored are typically so sporadic and sparse in time that average consumption is in microwatts. Still, tiny batteries cannot supply power for long, so power supplies cannot afford to burn much power. This is why reducing the power that switched‐inductor supplies lose when delivering microwatts is critical. For these power levels, balancing switches to deliver fixed energy packets in discontinuous‐conduction mode and adjusting their frequency to modify power level is the most efficient means of managing a DC–DC converter. In other words, fixing the inductor's peak current and adjusting frequency is more efficient than fixing frequency and adjusting peak current. In fact, experimental measurements show that fixing peak current to 6 mA and adjusting frequency to supply up to 250 µW is 2–10% more efficient than fixing frequencies at 40, 80, and 120 kHz and 1.4–7% more efficient than fixing currents at 5 and 10 mA.
56 Gbit/s OOK transmission with 20 GHz electronics by resonating segmented electrode InP Mach–Zehnder modulator
Authors: Aimone A. , Fiol G. , Gruner M. , Schell M. 
Published: October 2015

A resonating segmented Mach–Zehnder modulator with peaking transfer function is designed and fabricated in InP. The modulator is able to transmit a 56 Gbit/s on–off keying signal although the driver is limited to 20 GHz bandwidth. Bit error ratio over dispersion and optical signal‐to‐noise ratio are measured and show substantial advantage over their non‐resonating counterparts.
Experimental 2.4 GHz CMOS RF front‐ends for non‐contact vital‐sign sensing
Authors: Wang S. , Chang R.‐H. 
Published: October 2015

A 2.4 GHz CMOS front‐ends for non‐contact vital‐sign sensing including respiration and heartbeat is presented. The sensor using one circulator and one differential oscillator not only achieves the injection‐locked function but also reduces the system complexity. Moreover, the injection‐locked signals are then down‐converted by a phase demodulator constituted by a lumped power divider and a mixer. Finally, the signals are bandpass filtered and amplified for subsequently performing the vital signals. Under total power consumption of 32 mW, the respiration and heartbeat information can be recognised correctly up to 1.2 m away from the subject.
Climate change and insect pest distribution range.
Authors: Battisti A. , Larsson S. 
Published: October 2015

Abstract

The dynamics of species' distribution, in particular when it comes to predicting the outcomes of climate change-inflicted variations in the range distributions of insect pests. Several insect life history traits, such as survival, growth rate and voltinism, are likely to change in a warmer environment, and it is to be expected that at least some changes will contribute to altered range edges. For many insect taxa, range expansions are not easy to detect, simply because their presence remains undetected in habitats at range edges, where they are likely to occur at low densities. Insect pests are a group for which information on range expansion is beginning to accumulate, for the obvious reason that their effects on managed ecosystems often require action. Thus, increasingly managers of agriculture and forestry are concerned with the predicted range expansions of important insect pests. This chapter offers an update on the range expansions of insect pests in agriculture and forestry, native and alien. We summarize information from the literature where climate change has been interpreted as, or predicted to become, the driver of range expansion. We discuss the type of evidence for the expansion, ongoing or predicted to occur, and aim to classify according to its empirical nature. A critical read of the database of the literature on climate change resulted in surprisingly few documented examples of climate change-induced range expansion. Of course, long-term trends in the distribution and abundance of insect pests are notoriously difficult to document. Thus, it is possible that more insect pests could have responded to climate change, or are likely to do so in the near future, than can be detected in our literature search. It is also possible, however, that biological systems, including insect pests, are less sensitive to direct climate effects than previously thought (due to the buffering effects of trophic interactions). Future research needs to focus more on the mechanisms of responses to changed climate in order to understand better, and predict more accurately, the likelihood that insect pests will expand their outbreak range.