bluuebunny/crossref_metadata_2025 huggingface dataset:
In vivo neurochemical measurements in cerebral tissues using a droplet-based monitoring system
Authors: Petit-Pierre Guillaume , Colin Philippe , Laurer Estelle , Déglon Julien , Bertsch Arnaud , Thomas Aurélien , Schneider Bernard L. , Renaud Philippe
Published: October 2017

Direct collection of extracellular fluid (ECF) plays a central role in the monitoring of neurological disorders. Current approaches using microdialysis catheters are however drastically limited in term of temporal resolution. Here we show a functional in vivo validation of a droplet collection system included at the tip of a neural probe. The system comprises an advanced droplet formation mechanism which enables the collection of neurochemicals present in the brain ECF at high-temporal resolution. The probe was implanted in a rat brain and could successfully collect fluid samples organized in a train of droplets. A microfabricated target plate compatible with most of the surface-based detection methods was specifically developed for sample analysis. The time-resolved brain-fluid samples are analyzed using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The results provide a time evolution picture of the cerebral tissues neurochemical composition for selected elements known for their involvement in neurodegenerative diseases.
Songbirds work around computational complexity by learning song vocabulary independently of sequence
Authors: Lipkind Dina , Zai Anja T. , Hanuschkin Alexander , Marcus Gary F. , Tchernichovski Ofer , Hahnloser Richard H. R.
Published: October 2017

While acquiring motor skills, animals transform their plastic motor sequences to match desired targets. However, because both the structure and temporal position of individual gestures are adjustable, the number of possible motor transformations increases exponentially with sequence length. Identifying the optimal transformation towards a given target is therefore a computationally intractable problem. Here we show an evolutionary workaround for reducing the computational complexity of song learning in zebra finches. We prompt juveniles to modify syllable phonology and sequence in a learned song to match a newly introduced target song. Surprisingly, juveniles match each syllable to the most spectrally similar sound in the target, regardless of its temporal position, resulting in unnecessary sequence errors, that they later try to correct. Thus, zebra finches prioritize efficient learning of syllable vocabulary, at the cost of inefficient syntax learning. This strategy provides a non-optimal but computationally manageable solution to the task of vocal sequence learning.
INA complex liaises the F1Fo-ATP synthase membrane motor modules
Authors: Naumenko Nataliia , Morgenstern Marcel , Rucktäschel Robert , Warscheid Bettina , Rehling Peter
Published: October 2017

The F1F0-ATP synthase translates a proton flux across the inner mitochondrial membrane into a mechanical rotation, driving anhydride bond formation in the catalytic portion. The complex’s membrane-embedded motor forms a proteinaceous channel at the interface between Atp9 ring and Atp6. To prevent unrestricted proton flow dissipating the H+-gradient, channel formation is a critical and tightly controlled step during ATP synthase assembly. Here we show that the INA complex (INAC) acts at this decisive step promoting Atp9-ring association with Atp6. INAC binds to newly synthesized mitochondrial-encoded Atp6 and Atp8 in complex with maturation factors. INAC association is retained until the F1-portion is built on Atp6/8 and loss of INAC causes accumulation of the free F1. An independent complex is formed between INAC and the Atp9 ring. We conclude that INAC maintains assembly intermediates of the F1 F0-ATP synthase in a primed state for the terminal assembly step–motor module formation.
Parallel genome-wide screens identify synthetic viable interactions between the BLM helicase complex and Fanconi anemia
Authors: Moder Martin , Velimezi Georgia , Owusu Michel , Mazouzi Abdelghani , Wiedner Marc , Ferreira da Silva Joana , Robinson-Garcia Lydia , Schischlik Fiorella , Slavkovsky Rastislav , Kralovics Robert , Schuster Michael , Bock Christoph , Ideker Trey , Jackson Stephen P. , Menche Jörg , Loizou Joanna I.
Published: October 2017

Maintenance of genome integrity via repair of DNA damage is a key biological process required to suppress diseases, including Fanconi anemia (FA). We generated loss-of-function human haploid cells for FA complementation group C (FANCC), a gene encoding a component of the FA core complex, and used genome-wide CRISPR libraries as well as insertional mutagenesis to identify synthetic viable (genetic suppressor) interactions for FA. Here we show that loss of the BLM helicase complex suppresses FANCC phenotypes and we confirm this interaction in cells deficient for FA complementation group I and D2 (FANCI and FANCD2) that function as part of the FA I-D2 complex, indicating that this interaction is not limited to the FA core complex, hence demonstrating that systematic genome-wide screening approaches can be used to reveal genetic viable interactions for DNA repair defects.
The Polycomb group protein CBX6 is an essential regulator of embryonic stem cell identity
Authors: Santanach Alexandra , Blanco Enrique , Jiang Hua , Molloy Kelly R. , Sansó Miriam , LaCava John , Morey Lluis , Di Croce Luciano
Published: October 2017

Polycomb group proteins (PcG) are transcriptional repressors that control cell identity and development. In mammals, five different CBX proteins associate with the core Polycomb repressive complex 1 (PRC1). In mouse embryonic stem cells (ESCs), CBX6 and CBX7 are the most highly expressed CBX family members. CBX7 has been recently characterized, but little is known regarding the function of CBX6. Here, we show that CBX6 is essential for ESC identity. Its depletion destabilizes the pluripotency network and triggers differentiation. Mechanistically, we find that CBX6 is physically and functionally associated to both canonical PRC1 (cPRC1) and non-canonical PRC1 (ncPRC1) complexes. Notably, in contrast to CBX7, CBX6 is recruited to chromatin independently of H3K27me3. Taken together, our findings reveal that CBX6 is an essential component of ESC biology that contributes to the structural and functional complexity of the PRC1 complex.
Neural activations associated with feedback and retrieval success
Authors: Wiklund-Hörnqvist Carola , Andersson Micael , Jonsson Bert , Nyberg Lars
Published: October 2017

There is substantial behavioral evidence for a phenomenon commonly called “the testing effect”, i.e. superior memory performance after repeated testing compared to re-study of to-be-learned materials. However, considerably less is known about the underlying neuro-cognitive processes that are involved in the initial testing phase, and thus underlies the actual testing effect. Here, we investigated functional brain activity related to test-enhanced learning with feedback. Subjects learned foreign vocabulary across three consecutive tests with correct-answer feedback. Functional brain-activity responses were analyzed in relation to retrieval and feedback events, respectively. Results revealed up-regulated activity in fronto-striatal regions during the first successful retrieval, followed by a marked reduction in activity as a function of improved learning. Whereas feedback improved behavioral performance across consecutive tests, feedback had a negligable role after the first successful retrieval for functional brain-activity modulations. It is suggested that the beneficial effects of test-enhanced learning is regulated by feedback-induced updating of memory representations, mediated via the striatum, that might underlie the stabilization of memory commonly seen in behavioral studies of the testing effect.
Application of Multimodal Navigation together with Fluorescein Angiography in Microsurgical Treatment of Cerebral Arteriovenous Malformations
Authors: Feng Shiyu , Zhang Yanyang , Sun Zhenghui , Wu Chen , Xue Zhe , Ma Yudong , Jiang Jinli
Published: October 2017

This study aimed to explore the clinical applications of multimodal navigation combined with indocyanine green (ICG) fluorescein angiography in microsurgical treatment of cerebral arteriovenous malformations (AVMs). We retrospectively collected 52 patients with AVMs. Assisted by anatomic image, we reestablished three-dimensional structure using preoperative functional magnetic resonance imaging (fMRI) and Diffusion tensor imaging (DTI). The operation for lesion resection was finished under the assistance of neuro-navigation. ICG fluorescein angiography was performed for 16 of the study subjects, meanwhile, FLOW800 was used to rebuild blood vessel color visual image. Brain angiography was performed 1 week after the operation to check residual malformations. The patients’ status was estimated by Modified Rankin Scale score. Of the AVMs, 92.3% (48/52) were totally removed, without severe side events. Among the patients, fluorescein angiography was carried out up to 58 times for 16 cases. All of these 16 cases were confirmed with malformations and 14 of them had draining vein. The total resection rate of these 16 cases reached 100%, and the occurrence rate of postoperative complications was not significantly increased. During the operation of lesion resection, the application of multimodal navigation could effectively protect functional cortex and conduction pathway.
Identifying stably expressed housekeeping genes in the endometrium of fertile women, women with recurrent implantation failure and recurrent miscarriages
Authors: Stocker Linden , Cagampang Felino , Cheong Ying
Published: October 2017

Housekeeping genes (HKG) are presumed to be constitutively expressed throughout tissue types but recent studies have shown they vary with pathophysiology. Often, validation of appropriate HKG is not made. There is no consensus on which HKGs are most stably expressed in endometrial tissue so this study aimed to identify the most stable HKG in the endometrium of women with recurrent implantation failure (RIF) and recurrent miscarriages (RM). Inclusion criteria were women between 25–45 years (n = 45) suffering recurrent miscarriage (RM), recurrent implantation failure (RIF) or fertile controls. Endometrial biopsies were taken and total RNA extraction, cDNA synthesis and PCR was performed using 10 candidate HKG. The genes were arranged in terms of stability and normalisation was determined. Several HKGs not previously tested in endometrial samples were found to be more stable than those previously identified as the most stable. Of these, the 5 most stable HKG (in order of stability) werePrdm4(PR domain 4) > Ube4a(Ubiquitin-Conjugating Enzyme 4a) > Enox2(Ecto-NOX Disulfide-Thiol Exchanger 2) > Ube2d2(Ubiquitin-conjugating enzyme E2D 2) > Actb(Actin beta). We therefore recommend using at least four of the aforementioned HKG for normalisation of endometrial tissues taken from patients with RM and RIF.
Erratum: Thickness-dependent Crack Propagation in Uniaxially Strained Conducting Graphene Oxide Films on Flexible Substrates
Authors: Sakorikar Tushar , Kavitha Maheswari Kavirajan , Vayalamkuzhi Pramitha , Jaiswal Manu
Published: October 2017

A correction to this article has been published and is linked from the HTML version of this paper. The error has been fixed in the paper.
Modulation of the Vault Protein-Protein Interaction for Tuning of Molecular Release
Authors: Yu Kang , Yau Yin Hoe , Sinha Ameya , Tan Tabitha , Kickhoefer Valerie A. , Rome Leonard H. , Lee Hwankyu , Shochat Susana G. , Lim Sierin
Published: October 2017

Vaults are naturally occurring ovoid nanoparticles constructed from a protein shell that is composed of multiple copies of major vault protein (MVP). The vault-interacting domain of vault poly(ADP-ribose)-polymerase (INT) has been used as a shuttle to pack biomolecular cargo in the vault lumen. However, the interaction between INT and MVP is poorly understood. It is hypothesized that the release rate of biomolecular cargo from the vault lumen is related to the interaction between MVP and INT. To tune the release of molecular cargos from the vault nanoparticles, we determined the interactions between the isolated INT-interacting MVP domains (iMVP) and wild-type INT and compared them to two structurally modified INT: 15-amino acid deletion at the C terminus (INTΔC15) and histidine substituted at the interaction surface (INT/DSA/3 H) to impart a pH-sensitive response. The apparent affinity constants determined using surface plasmon resonance (SPR) biosensor technology are 262 ± 4 nM for iMVP/INT, 1800 ± 160 nM for iMVP/INTΔC15 at pH 7.4. The INT/DSA/3 H exhibits stronger affinity to iMVP (KDapp
 = 24 nM) and dissociates at a slower rate than wild-type INT at pH 6.0.
Using non-invasive transcranial stimulation to improve motor and cognitive function in Parkinson’s disease: a systematic review and meta-analysis
Authors: Goodwill Alicia M. , Lum Jarrad A. G. , Hendy Ashlee M. , Muthalib Makii , Johnson Liam , Albein-Urios Natalia , Teo Wei-Peng
Published: October 2017

Parkinson's disease (PD) is a neurodegenerative disorder affecting motor and cognitive abilities. There is no cure for PD, therefore identifying safe therapies to alleviate symptoms remains a priority. This meta-analysis quantified the effectiveness of repetitive transcranial magnetic stimulation (rTMS) and transcranial electrical stimulation (TES) to improve motor and cognitive dysfunction in PD. PubMed, EMBASE, Web of Science, Google Scholar, Scopus, Library of Congress and Cochrane library were searched. 24 rTMS and 9 TES studies (n = 33) with a sham control group were included for analyses. The Physiotherapy Evidence Database and Cochrane Risk of Bias showed high quality (7.5/10) and low bias with included studies respectively. Our results showed an overall positive effect in favour of rTMS (SMD = 0.394, CI [0.106–0.683], p = 0.007) and TES (SMD = 0.611, CI [0.188–1.035], p = 0.005) compared with sham stimulation on motor function, with no significant differences detected between rTMS and TES (Q [1] = 0.69, p = 0.406). Neither rTMS nor TES improved cognition. No effects for stimulation parameters on motor or cognitive function were observed. To enhance the clinical utility of non-invasive brain stimulation (NBS), individual prescription of stimulation parameters based upon symptomology and resting excitability state should be a priority of future research.
Prevalence and genotype distribution of human papillomavirus in 961,029 screening tests in southeastern China (Zhejiang Province) between 2011 and 2015
Authors: Chen Xiao , Xu Haiou , Xu Wanwan , Zeng Wenjie , Liu Jinwei , Wu Qing , Zhao Xiaofeng , Jiang Tang
Published: October 2017

Human papillomavirus infection plays a key role in the development of cervical cancer. To establish a foundation for HPV-based screening and vaccination programs, we investigated the HPV prevalence and genotypic distributions in Chinese women from Zhejiang Province. Between 2011 and 2015, a total of 961,029 samples from 2021 clinical hospitals were tested HPV genotype by a PCR-based hybridization gene chip assay, and 443,890 samples were evaluated cervical cytology by liquid-based cytology analysis. Our results showed that the positive rate for HPV was 20.54%, which ranged from 28.72% to 17.81% and varied by year of recruitment. Age-specific prevalence showed a “two-peak” pattern, with the ≤20-year-old group presenting the highest HPV infection rate, followed by 61–70-year-old group. Overall, the most prevalent genotypes were HPV16, 52 and 58. Additionally, the odds ratios for the prevalence of the HR-HPV, LR-HPV and HPV-negative groups with abnormal cytology were 12.56, 3.21 and 0.06, respectively. Among genotypes, HPV 16 has been found to have the highest OR, followed by HPV58, 18, 52. Here, we present data regarding the prevalence and type distribution of HPV infection, which can serve as valuable reference to guide nationwide cervical cancer screening and HPV vaccination programs.
Causes of variation among rice models in yield response to CO2 examined with Free-Air CO2 Enrichment and growth chamber experiments
Authors: Hasegawa Toshihiro , Li Tao , Yin Xinyou , Zhu Yan , Boote Kenneth , Baker Jeffrey , Bregaglio Simone , Buis Samuel , Confalonieri Roberto , Fugice Job , Fumoto Tamon , Gaydon Donald , Kumar Soora Naresh , Lafarge Tanguy , Marcaida III Manuel , Masutomi Yuji , Nakagawa Hiroshi , Oriol Philippe , Ruget Françoise , Singh Upendra , Tang Liang , Tao Fulu , Wakatsuki Hitomi , Wallach Daniel , Wang Yulong , Wilson Lloyd Ted , Yang Lianxin , Yang Yubin , Yoshida Hiroe , Zhang Zhao , Zhu Jianguo
Published: October 2017

The CO2 fertilization effect is a major source of uncertainty in crop models for future yield forecasts, but coordinated efforts to determine the mechanisms of this uncertainty have been lacking. Here, we studied causes of uncertainty among 16 crop models in predicting rice yield in response to elevated [CO2] (E-[CO2]) by comparison to free-air CO2 enrichment (FACE) and chamber experiments. The model ensemble reproduced the experimental results well. However, yield prediction in response to E-[CO2] varied significantly among the rice models. The variation was not random: models that overestimated at one experiment simulated greater yield enhancements at the others. The variation was not associated with model structure or magnitude of photosynthetic response to E-[CO2] but was significantly associated with the predictions of leaf area. This suggests that modelled secondary effects of E-[CO2] on morphological development, primarily leaf area, are the sources of model uncertainty. Rice morphological development is conservative to carbon acquisition. Uncertainty will be reduced by incorporating this conservative nature of the morphological response to E-[CO2] into the models. Nitrogen levels, particularly under limited situations, make the prediction more uncertain. Improving models to account for [CO2] × N interactions is necessary to better evaluate management practices under climate change.
Functional divergence and intron variability during evolution of angiosperm TERMINAL FLOWER1 (TFL1) genes
Authors: Gao Jian , Huang Bing-Hong , Wan Yu-Ting , Chang JenYu , Li Jun-Qing , Liao Pei-Chun
Published: October 2017

The protein encoded by the TERMINAL FLOWER1 (TFL1) gene maintains indeterminacy in inflorescence meristem to repress flowering, and has undergone multiple duplications. However, basal angiosperms have one copy of a TFL1-like gene, which clusters with eudicot TFL1/CEN paralogs. Functional conservation has been reported in the paralogs CENTRORADIALIS (CEN) in eudicots, and ROOTS CURL IN NPA (RCNs) genes in monocots. In this study, long-term functional conservation and selective constraints were found between angiosperms, while the relaxation of selective constraints led to subfunctionalisation between paralogs. Long intron lengths of magnoliid TFL1-like gene contain more conserved motifs that potentially regulate TFL1/CEN/RCNs expression. These might be relevant to the functional flexibility of the non-duplicate TFL1-like gene in the basal angiosperms in comparison with the short, lower frequency intron lengths in eudicot and monocot TFL1/CEN/RCNs paralogs. The functionally conserved duplicates of eudicots and monocots evolved according to the duplication-degeneration-complementation model, avoiding redundancy by relaxation of selective constraints on exon 1 and exon 4. These data suggest that strong purifying selection has maintained the relevant functions of TFL1/CEN/RCNs paralogs on flowering regulation throughout the evolution of angiosperms, and the shorter introns with radical amino acid changes are important for the retention of paralogous duplicates.
Origami-based Building Blocks for Modular Construction of Foldable Structures
Authors: Mousanezhad Davood , Kamrava Soroush , Vaziri Ashkan
Published: October 2017

Origami, widely known as the ancient Japanese art of paper folding, has recently inspired a new paradigm of design for mechanical metamaterials and deployable structural systems. However, lack of rationalized design guidelines and scalable manufacturing methods has hindered their applications. To address this limitation, we present analytical methods for designing origami-based closed-loop units with inherent foldability, and for predicting their folding response (e.g., folding force, bistability, and area and volume change by folding). These units can be employed as building blocks for application-driven design and modular construction of foldable structures with desired performance and manufacturing scalability.
Abnormal contractility in human heart myofibrils from patients with dilated cardiomyopathy due to mutations in TTN and contractile protein genes
Authors: Vikhorev Petr G. , Smoktunowicz Natalia , Munster Alex B. , Copeland O’Neal , Kostin Sawa , Montgiraud Cecile , Messer Andrew E. , Toliat Mohammad R. , Li Amy , dos Remedios Cristobal G. , Lal Sean , Blair Cheavar A. , Campbell Kenneth S. , Guglin Maya , Richter Manfred , Knöll Ralph , Marston Steven B.
Published: October 2017

Dilated cardiomyopathy (DCM) is an important cause of heart failure. Single gene mutations in at least 50 genes have been proposed to account for 25–50% of DCM cases and up to 25% of inherited DCM has been attributed to truncating mutations in the sarcomeric structural protein titin (TTNtv). Whilst the primary molecular mechanism of some DCM-associated mutations in the contractile apparatus has been studied in vitro and in transgenic mice, the contractile defect in human heart muscle has not been studied. In this study we isolated cardiac myofibrils from 3 TTNtv mutants, and 3 with contractile protein mutations (TNNI3 K36Q, TNNC1 G159D and MYH7 E1426K) and measured their contractility and passive stiffness in comparison with donor heart muscle as a control. We found that the three contractile protein mutations but not the TTNtv mutations had faster relaxation kinetics. Passive stiffness was reduced about 38% in all the DCM mutant samples. However, there was no change in maximum force or the titin N2BA/N2B isoform ratio and there was no titin haploinsufficiency. The decrease in myofibril passive stiffness was a common feature in all hearts with DCM-associated mutations and may be causative of DCM.
Coherence transformations in single qubit systems
Authors: Shi Hai-Long , Wang Xiao-Hui , Liu Si-Yuan , Yang Wen-Li , Yang Zhan-Ying , Fan Heng
Published: October 2017

We investigate the single qubit transformations under several typical coherence-free operations, such as, incoherent operation (IO), strictly incoherent operation (SIO), physically incoherent operation (PIO), and coherence-preserving operation (CPO). Quantitative connection has been built between IO and SIO in single qubit systems. Moreover, these coherence-free operations have a clear hierarchical relationship in single qubit systems: CPO ⊂ PIO ⊂ SIO=IO. A new and explicit proof for the necessary and sufficient condition of single qubit transformation via IO or SIO has been provided, which indicates that SIO with only two Kraus operators are enough to realize this transformation. The transformation regions of single qubits via CPO and PIO are also given. Our method provides a geometric illustration to analyze single qubit coherence transformations by introducing the Bloch sphere depiction of the transformation regions, and tells us how to construct the corresponding coherence-free operations.
A novel peptide that improves metabolic parameters without adverse central nervous system effects
Authors: Reckziegel Patrícia , Festuccia William T. , Britto Luiz R. G. , Jang Karen L. Lopes , Romão Carolina M. , Heimann Joel C. , Fogaça Manoela V. , Rodrigues Naielly S. , Silva Nicole R. , Guimarães Francisco S. , Eichler Rosangela A. S. , Gupta Achla , Gomes Ivone , Devi Lakshmi A. , Heimann Andrea S. , Ferro Emer S.
Published: October 2017

Intracellular peptides generated by limited proteolysis are likely to function inside and outside cells and could represent new possibilities for drug development. Here, we used several conformational-sensitive antibodies targeting G-protein coupled receptors to screen for novel pharmacological active peptides. We find that one of these peptides, DITADDEPLT activates cannabinoid type 1 receptors. Single amino acid modifications identified a novel peptide, DIIADDEPLT (Pep19), with slightly better inverse agonist activity at cannabinoid type 1 receptors. Pep19 induced uncoupling protein 1 expression in both white adipose tissue and 3T3-L1 differentiated adipocytes; in the latter, Pep19 activates pERK1/2 and AKT signaling pathways. Uncoupling protein 1 expression induced by Pep19 in 3T3-L1 differentiated adipocytes is blocked by AM251, a cannabinoid type 1 receptors antagonist. Oral administration of Pep19 into diet-induced obese Wistar rats significantly reduces adiposity index, whole body weight, glucose, triacylglycerol, cholesterol and blood pressure, without altering heart rate; changes in the number and size of adipocytes were also observed. Pep19 has no central nervous system effects as suggested by the lack of brain c-Fos expression, cell toxicity, induction of the cannabinoid tetrad, depressive- and anxiety-like behaviors. Therefore, Pep19 has several advantages over previously identified peripherally active cannabinoid compounds, and could have clinical applications.
Modeling cadmium-induced endothelial toxicity using human pluripotent stem cell-derived endothelial cells
Authors: Tang Ling , Su Jun , Liang Ping
Published: October 2017

Cadmium (Cd) is a harmful heavy metal that results in vascular diseases such as atherosclerosis. Prior evidence revealed that Cd induced endothelial cell (EC) death and dysfunction, supporting that ECs are a primary target of Cd-induced toxicity, and can cause severe pathologies of vascular diseases. However, the underlying mechanisms remain unclear. In this study, we investigated the mechanisms of Cd-induced endothelial toxicity in a human model system of H9 human pluripotent stem cell-derived endothelial cells (H9-ECs). We showed that H9-ECs were susceptible to CdCl2 induction, leading to detrimental changes of cell structure and significantly elevated level of apoptosis. We demonstrated that CdCl2-treated H9-ECs gave rise to a clear EC dysfunction phenotype and significantly differential transcriptomic profile. Signaling pathway analysis revealed that P38 or ERK signaling pathway is critical to cadmium-induced EC apoptosis and dysfunction, and inhibition of P38 or ERK effectively rescued CdCl2-induced endothelial toxicity in H9-ECs. Conclusively, hPSC-ECs can be a reliable model to recapitulate the EC pathological features and transcriptomic profile, which may provide a unique platform for understanding the cellular and molecular mechanisms of Cd-induced endothelial toxicity and for identifying therapeutic drugs for Cd-induced vascular diseases.
An Efficient Evaluation of F-doped Polyanion Cathode Materials with Long Cycle Life for Na-Ion Batteries Applications
Authors: Muruganantham Rasu , Chiu Yi-Tang , Yang Chun-Chuen , Wang Chin-Wei , Liu Wei-Ren
Published: October 2017

A series of Na3−x
V2(PO4−x
F
x
)3 (x = 0, 0.1, 0.15 and 0.3) polyanion cathode materials are synthesized via a sol-gel method. The optimal doping concentration of F in Na3V2(PO4)3 is 0.15 mol %. By neutron powder diffraction data, the chemical composition of as-synthesized material is Na2.85V2(PO3.95F0.05)3. The half-cell of Na2.85V2(PO3.95F0.05)3 cathode exhibits a stable discharge capacity of 103 mAh g−1 and 93% of capacity retention over 250 cycles without decay at 0.1 A g−1, which is higher than that of bare Na3V2(PO4)3 (98 mAh g−1). The high rate capability of Na2.85V2(PO3.95F0.05)3 is also dramatically enhanced via increase the conductivity of host material by F-doping. Moreover, the symmetrical Na-ion full-cell is fabricated using Na2.85V2(PO3.95F0.05)3 as cathode and anode materials. It is achieved that the good reversibility and superior cycling stability about 98% of capacity retention with ~100% of coulombic efficiency at 1.0 A g−1 throughout 1000 cycles. These results demonstrate that the optimal amount of Na2.85V2(PO3.95F0.05)3 is a distinctive potential candidate for excellent long-term cyclic stability with high rate low-cost energy storage applications.
A solar radiation database for Chile
Authors: Molina Alejandra , Falvey Mark , Rondanelli Roberto
Published: October 2017

Chile hosts some of the sunniest places on earth, which has led to a growing solar energy industry in recent years. However, the lack of high resolution measurements of solar irradiance becomes a critical obstacle for both financing and design of solar installations. Besides the Atacama Desert, Chile displays a large array of “solar climates” due to large latitude and altitude variations, and so provides a useful testbed for the development of solar irradiance maps. Here a new public database for surface solar irradiance over Chile is presented. This database includes hourly irradiance from 2004 to 2016 at 90 m horizontal resolution over continental Chile. Our results are based on global reanalysis data to force a radiative transfer model for clear sky solar irradiance and an empirical model based on geostationary satellite data for cloudy conditions. The results have been validated using 140 surface solar irradiance stations throughout the country. Model mean percentage error in hourly time series of global horizontal irradiance is only 0.73%, considering both clear and cloudy days. The simplicity and accuracy of the model over a wide range of solar conditions provides confidence that the model can be easily generalized to other regions of the world.
Dissociating the effects of alternative early-life feeding schedules on the development of adult depression-like phenotypes
Authors: Neville Vikki , Andrews Clare , Nettle Daniel , Bateson Melissa
Published: October 2017

Early-life adversity is associated with increased vulnerability to depression in humans, and depression-like phenotypes in animals. However, different types of adverse experience may leave different signatures in adulthood. We experimentally manipulated the Amount of food delivered to European starling nestlings and the begging Effort required to obtain food during early development. Here, we report behavioural data in adulthood from a task that assessed sensitivity to shifts in reward magnitude characteristic of depression-like low mood. Birds that had experienced Hard Effort were more food motivated than birds that had experienced Easy Effort. Both Effort and Amount affected sensitivity to shifts in reward magnitude: Hard Effort birds showed an enhanced negative contrast effect following loss of reward (‘disappointment’), and Lean Amount birds failed to show a normal positive contrast effect following gain in reward (a lack of ‘elation’). Therefore, the feeding schedule experienced for just 10 days in early life caused enduring effects on feeding motivation and sensitivity to reward loss/gain consistent with human depression. Furthermore, the contrast effects were specific to different types of adversity. These results highlight the importance of early-life feeding schedules in the development of depression-like phenotypes.
Ultra-Broadband, Lithography-Free, and Large-Scale Compatible Perfect Absorbers: The Optimum Choice of Metal layers in Metal-Insulator Multilayer Stacks
Authors: Abedini Dereshgi Sina , Ghobadi Amir , Hajian Hodjat , Butun Bayram , Ozbay Ekmel
Published: October 2017

We report ultra-broadband perfect absorbers for visible and near-infrared applications that are based on multilayers of metal-insulator (MI) stacks fabricated employing straightforward layer deposition techniques and are, therefore, lithography-free and large-scale compatible. We scrutinize the impact of different physical parameters of an MIMI absorber structure with analysis of each contributing metal layer. After obtaining the optimal design parameters (i.e. material selection and their thicknesses) with both simulation and numerical analysis (Transfer Matrix Method) methods, an experimental sample is fabricated and characterized. Our fabricated MIMI absorber consists of an optically thick tungsten (W) back reflector layer followed by 80 nm aluminum oxide (Al2O3), 10 nm titanium (Ti), and finally another 80 nm Al2O3. The experimental results demonstrate over 90 percent absorption between 400 nm and 1640 nm wavelengths that is optimized for ultra-broadband absorption in MIMI structures. Moreover, the impedance matching method with free-space is used to shed light on the metallic layer selection process.
Cardio-audio synchronization drives neural surprise response
Authors: Pfeiffer Christian , De Lucia Marzia
Published: October 2017

Successful prediction of future events depends on the brain’s capacity to extract temporal regularities from sensory inputs. Neuroimaging studies mainly investigated regularity processing for exteroceptive sensory inputs (i.e. from outside the body). Here we investigated whether interoceptive signals (i.e. from inside the body) can mediate auditory regularity processing. Human participants passively listened to sound sequences presented in synchrony or asynchrony to their heartbeat while concomitant electroencephalography was recorded. We hypothesized that the cardio-audio synchronicity would induce a brain expectation of future sounds. Electrical neuroimaging analysis revealed a surprise response at 158–270 ms upon omission of the expected sounds in the synchronous condition only. Control analyses ruled out that this effect was trivially based on expectation from the auditory temporal structure or on differences in heartbeat physiological signals. Implicit neural monitoring of temporal regularities across interoceptive and exteroceptive signals drives prediction of future events in auditory sequences.
Site-specific and kinetic characterization of enzymatic and nonenzymatic protein acetylation in bacteria
Authors: Wang Miao-Miao , You Di , Ye Bang-Ce
Published: October 2017

Reversible Nε-lysine acetylation has emerging as an important metabolic regulatory mechanism in microorganisms. Herein, we systematically investigated the site-specific and kinetic characterization of enzymatic (lysine acetyltransferase) and nonenzymatic acetylation (AcP-dependent or Acyl-CoA-dependent), as well as their different effect on activity of metabolic enzyme (AMP-forming acetyl-CoA synthetase, Acs). It was found that Bacillus subtilis acetyl-CoA synthetase (BsAcsA) can be acetylated in vitro either catalytically by lysine acetyltransferase BsAcuA and Ac-CoA (at low concentration), or nonenzymatically by Ac-CoA or AcP (at high concentration). Two distinct mechanisms show preference for different lysine acetylation site (enzymatic acetylation for K549 and nonenzymatic acetylation for K524), and reveal different dynamics of relative acetylation changes at these lysine sites. The results demonstrated that lysine residues on the same protein exhibit different acetylation reactivity with acetyl-phosphate and acetyl-CoA, which was determined by surface accessibility, three-dimensional microenvironment, and pKa value of lysine. Acetyl-CoA synthetase is inactivated by AcuA-catalyzed acetylation, but not by nonenzymatic acetylation.
Wild-captive interactions and economics drive dynamics of Asian elephants in Laos
Authors: Maurer Gilles , Rashford Benjamin S. , Chanthavong Vatsana , Mulot Baptiste , Gimenez Olivier
Published: October 2017

The interactions between wild and captive populations of Asian elephants (Elephas maximus) persist in most countries of the species distribution, notably through the reproduction between captive females and wild males. However, these complex interactions have been poorly studied, despite their relevance for conservation of this endangered species. Laos has a centuries-long tradition of raising Asian elephants. Besides being cultural icons, captive elephants are inextricably linked to economics through their work in forestry. Using an ecological-economic model, we investigated the effect of socio-economic strategies on fecundity of the Lao population whose dynamics is shaped by human practices. We demonstrated that fecundity is impacted by: i) the dynamics of the wild elephant pool through mating of captive females by wild males, and ii) the financial incentive of elephant owners to breed their animals. As a result, we expect fecundity to rise in response to increases in elephant prices. The captive population will tend towards an asymptotic limit determined by the wild pool growth rate. However, the population will tend to extinction if exports continue. Our ecological-economic approach, by accounting for economic incentives, allows us to predict new equilibria that can serve as a baseline for designing sustainable management strategies for the species.
Perceptual integration and attention in human extrastriate cortex
Authors: Strappini Francesca , Galati Gaspare , Martelli Marialuisa , Di Pace Enrico , Pitzalis Sabrina
Published: October 2017

Visual crowding is a perceptual phenomenon with far-reaching implications in both perceptual (e.g., object recognition and reading) and clinical (e.g., developmental dyslexia and visual agnosia) domains. Here, we combined event-related fMRI measurements and wide-field brain mapping methods to investigate whether the BOLD response evoked by visual crowding is modulated by different attentional conditions. Participants underwent two sessions of psychophysical training outside the scanner, and then fMRI BOLD activity was measured simultaneously in early visual areas (including the visual word form area, VWFA), while they viewed strongly-crowded and weakly-crowded Gabor patches in attended and unattended conditions. We found that crowding increased BOLD activity in a network of areas including V1, V2, V3A, V4/V8, and VWFA. In V4/V8 and VWFA we found an increased activity related to attention. The effect of crowding in V1 was recorded only when attention was fully devoted to the target location. Our results provide evidence that some area beyond V1 might be the likely candidate for the site of crowding, thus supporting the view of visual crowding as a mid-level visual phenomenon.
Rapid identification of staphylococci by Raman spectroscopy
Authors: Rebrošová Katarína , Šiler Martin , Samek Ota , Růžička Filip , Bernatová Silvie , Holá Veronika , Ježek Jan , Zemánek Pavel , Sokolová Jana , Petráš Petr
Published: October 2017

Clinical treatment of the infections caused by various staphylococcal species differ depending on the actual cause of infection. Therefore, it is necessary to develop a fast and reliable method for identification of staphylococci. Raman spectroscopy is an optical method used in multiple scientific fields. Recent studies showed that the method has a potential for use in microbiological research, too. Our work here shows a possibility to identify staphylococci by Raman spectroscopy. We present a method that enables almost 100% successful identification of 16 of the clinically most important staphylococcal species directly from bacterial colonies grown on a Mueller-Hinton agar plate. We obtained characteristic Raman spectra of 277 staphylococcal strains belonging to 16 species from a 24-hour culture of each strain grown on the Mueller-Hinton agar plate using the Raman instrument. The results show that it is possible to distinguish among the tested species using Raman spectroscopy and therefore it has a great potential for use in routine clinical diagnostics.
Zika Virus Infects Intermediate Progenitor Cells and Post-mitotic Committed Neurons in Human Fetal Brain Tissues
Authors: Lin Ming-Yi , Wang Yi-Ling , Wu Wan-Lin , Wolseley Victoria , Tsai Ming-Ting , Radic Vladimir , Thornton Matthew E. , Grubbs Brendan H. , Chow Robert H. , Huang I-Chueh
Published: October 2017

Zika virus (ZIKV) infection is associated with microcephaly in fetuses, but the pathogenesis of ZIKV-related microcephaly is not well understood. Here we show that ZIKV infects the subventricular zone in human fetal brain tissues and that the tissue tropism broadens with the progression of gestation. Our research demonstrates also that intermediate progenitor cells (IPCs) are the main target cells for ZIKV. Post-mitotic committed neurons become susceptible to ZIKV infection as well at later stages of gestation. Furthermore, activation of microglial cells, DNA fragmentation, and apoptosis of infected or uninfected cells could be found in ZIKV-infected brain tissues. Our studies identify IPCs as the main target cells for ZIKV. They also suggest that immune activation after ZIKV infection may play an important role in the pathogenesis of ZIKV-related microcephaly.
Non-linear effects and thermoelectric efficiency of quantum dot-based single-electron transistors
Authors: Talbo Vincent , Saint-Martin Jérôme , Retailleau Sylvie , Dollfus Philippe
Published: October 2017

By means of advanced numerical simulation, the thermoelectric properties of a Si-quantum dot-based single-electron transistor operating in sequential tunneling regime are investigated in terms of figure of merit, efficiency and power. By taking into account the phonon-induced collisional broadening of energy levels in the quantum dot, both heat and electrical currents are computed in a voltage range beyond the linear response. Using our homemade code consisting in a 3D Poisson-Schrödinger solver and the resolution of the Master equation, the Seebeck coefficient at low bias voltage appears to be material independent and nearly independent on the level broadening, which makes this device promising for metrology applications as a nanoscale standard of Seebeck coefficient. Besides, at higher voltage bias, the non-linear characteristics of the heat current are shown to be related to the multi-level effects. Finally, when considering only the electronic contribution to the thermal conductance, the single-electron transistor operating in generator regime is shown to exhibit very good efficiency at maximum power.
Identification and characterization of a novel β-glucosidase via metagenomic analysis of Bursaphelenchus xylophilus and its microbial flora
Authors: Zhang Lin , Fu Qiang , Li Wenpeng , Wang Bowen , Yin Xiaoyan , Liu Suyao , Xu Zhaonan , Niu Qiuhong
Published: October 2017

β-glucosidases catalyze the final step of cellulose hydrolysis and are essential in cellulose degradation. A β-glucosidase gene,cen502, was identified and isolated from a metagenomic library fromBursaphelenchus xylophilusvia functional screening. Analyses indicated thatcen502encodes a 465 amino acid polypeptide that contains a catalytic domain belonging to the glycoside hydrolase family 1 (GH1). Cen502 was heterologously expressed, purified, and biochemically characterized. Recombinant Cen502 displayed optimum enzymatic activity at pH 8.0 and 38 °C. The enzyme had highest specific activity to p-nitrophenyl-β-D-glucopyranoside (pNPG; 180.3 U/mg) and hadKmandVmaxvalues of 2.334 mol/ml and 9.017 μmol/min/mg, respectively. The addition of Fe2+and Mn2+significantly increased Cen502 β-glucosidase activity by 60% and 50%, respectively, while 10% and 25% loss of β-glucosidase activity was induced by addition of Pb2+and K+, respectively. Cen502 exhibited activity against a broad array of substrates, including cellobiose, lactose, salicin, lichenan, laminarin, and sophorose. However, Cen502 displayed a preference for the hydrolysis of β-1,4 glycosidic bonds rather than β-1,3, β-1,6, or β-1,2 bonds. Our results indicate that Cen502 is a novel β-glucosidase derived from bacteria associated withB. xylophilusand may represent a promising target to enhance the efficiency of cellulose bio-degradation in industrial applications.
OCT Amplitude and Speckle Statistics of Discrete Random Media
Authors: Almasian Mitra , van Leeuwen Ton G. , Faber Dirk J.
Published: October 2017

Speckle, amplitude fluctuations in optical coherence tomography (OCT) images, contains information on sub-resolution structural properties of the imaged sample. Speckle statistics could therefore be utilized in the characterization of biological tissues. However, a rigorous theoretical framework relating OCT speckle statistics to structural tissue properties has yet to be developed. As a first step, we present a theoretical description of OCT speckle, relating the OCT amplitude variance to size and organization for samples of discrete random media (DRM). Starting the calculations from the size and organization of the scattering particles, we analytically find expressions for the OCT amplitude mean, amplitude variance, the backscattering coefficient and the scattering coefficient. We assume fully developed speckle and verify the validity of this assumption by experiments on controlled samples of silica microspheres suspended in water. We show that the OCT amplitude variance is sensitive to sub-resolution changes in size and organization of the scattering particles. Experimentally determined and theoretically calculated optical properties are compared and in good agreement.
The influence of structural disorder and phonon on metal-to-insulator transition of VO
2
Authors: Hwang In-Hui , Jin Zhenlan , Park Chang-In , Han Sang-Wook
Published: October 2017

We used temperature-dependent x-ray absorption fine structure (XAFS) measurements to examine the local structural properties around vanadium atoms at the V K edge from VO2 films. A direct comparison of the simultaneously-measured resistance and XAFS regarding the VO2 films showed that the thermally-driven structural transition occurred prior to the resistance transition during a heating, while  this change simultaneously occured during a cooling. Extended-XAFS (EXAFS) analysis revealed significant increases of the Debye-Waller factors of the V-O and V-V pairs in the {111} direction of the R-phase VO2 that are due to the phonons of the V-V arrays along the same direction in a metallic phase. The existance of a substantial amount of structural disorder on the V-V pairs along the c-axis in both M1 and R phases indicates the structural instability of V-V arrays in the axis. The anomalous structural disorder that was observed on all atomic sites at the structural phase transition prevents the migration of the V 3d1 electrons, resulting in a Mott insulator in the M2-phase VO2.
Mycobacterial genomic DNA from used Xpert MTB/RIF cartridges can be utilised for accurate second-line genotypic drug susceptibility testing and spoligotyping
Authors: Venter Rouxjeane , Derendinger Brigitta , de Vos Margaretha , Pillay Samantha , Dolby Tanya , Simpson John , Kitchin Natasha , Ruiters Ashley , van Helden Paul D. , Warren Robin M. , Theron Grant
Published: October 2017

Xpert MTB/RIF (Xpert) is a widely-used test for tuberculosis (TB) and rifampicin-resistance. Second-line drug susceptibility testing (DST), which is recommended by policymakers, typically requires additional specimen collection that delays effective treatment initiation. We examined whether cartridge extract (CE) from used Xpert TB-positive cartridges was, without downstream DNA extraction or purification, suitable for both genotypic DST (MTBDRplus, MTBDRsl), which may permit patients to rapidly receive a XDR-TB diagnosis from a single specimen, and spoligotyping, which could facilitate routine genotyping. To determine the limit-of-detection and diagnostic accuracy, CEs from dilution series of drug-susceptible and -resistant bacilli were tested (MTBDRplus, MTBDRsl). Xpert TB-positive patient sputa CEs (n = 85) were tested (56 Xpert-rifampicin-susceptible, MTBDRplus and MTBDRsl; 29 Xpert-rifampicin-resistant, MTBDRsl). Spoligotyping was done on CEs from dilution series and patient sputa (n = 10). MTBDRplus had high non-valid result rates. MTBDRsl on CEs from dilutions ≥103CFU/ml (CT ≤ 24, >“low” Xpert semiquantitation category) was accurate, had low indeterminate rates and, on CE from sputa, highly concordant with MTBDRsl isolate results. CE spoligotyping results from dilutions ≥103CFU/ml and sputa were correct. MTBDRsl and spoligotyping on CE are thus highly feasible. These findings reduce the need for additional specimen collection and culture, for which capacity is limited in high-burden countries, and have implications for diagnostic laboratories and TB molecular epidemiology.