bluuebunny/crossref_metadata_2025 huggingface dataset:
ALIANZAS ANTI-EMBALSE Y LUCHAS HIDRO-EPISTEMOLÓGICAS. LOS RETOS DE LA GESTIÓN COLECTIVA DEL AGUA EN EL RÍO GRANDE, MÁLAGA, ESPAÑA
Authors: Duarte Abadía Bibiana , Boelens Rutgerd , Du Pré Lucas
Published: February 2019

En este artículo analizamos las luchas epistemológicas y retos que ha tenido el movimiento social en la subcuenca del río Grande frente a los diversos proyectos modernizadores que intentan transferir el agua rural hacia la ciudad de Málaga. El primero asociado a la construcción de un gran embalse y el segundo con la modernización de los sistemas de riego tradicionales. Concluimos que el reto está en desenmascarar el régimen de verdad que respalda los proyectos de modernidad hidráulica, reivindicar los derechos de uso y control colectivos del agua y así generar procesos de apropiación comunitaria para la defensa del río como un bien socio-ambiental, económico-cultural y político-epistemológico.
HACIA LA SOBERANIA ALIMENTARIA, ENTRE LA REORGANIZACION INSTITUCIONAL Y LA INICIATIVA LOCAL. EL PROYECTO COMUNITARIO DE RIEGO DE MARIANO ACOSTA (ECUADOR)
Authors: Recalt Christine , Valony Marie-Jeanne
Published: February 2019

Ecuador es una de las primeras naciones que ha incorporado en su texto constitucional el concepto de soberanía alimentaria. En su Carta Magna de 2008, el artículo 281 señala que la soberanía alimentaria constituye un objetivo estratégico y una obligación, y el artículo 282 requiere que el Estado prohíba el acaparamiento o la privatización del agua. En este contexto, la gestión y la regulación de los recursos hídricos han generado divergencias entre las autoridades centrales y las comunidades rurales. La aprobación de la Ley de Aguas de 2014 ha avivado estas discrepancias. A través del análisis del proyecto comunitario de Mariano Acosta en la provincia de Imbabura, este artículo cuestiona si los proyectos y las normas de riego promovidas por las agencias gubernamentales pueden ser compatibles con las posibilidades de las comunidades campesinas para alcanzar la “soberanía alimentaria”. Losresultados muestran que cada uno de los actores implicados parece perseguir agendas distintas.
MINERÍA DE ORO: PROMESAS, CONFLICTOS Y DESILUSIÓN EN CERRO DE SAN PEDRO, MÉXICO
Authors: Stoltenborg Didi , Boelens Rutgerd
Published: February 2019

Este artículo analiza los conflictos por los recursos agua y tierra en Cerro de San Pedro, México, cuando una empresa minera canadiense inició una mina a cielo abierto en este municipio. Examinamos diferentes posiciones en el conflicto entre la mina de oro y los habitantes locales, y cómo ambivalentes regulaciones nacionales y organismos gubernamentales permitieron que una empresa extranjera operara sin los permisos requeridos. Para analizar el conflicto utilizamos el marco de Escalones de Análisis de Derechos, que distingue cuatro capas de disputa: sobre los recursos; el contenido de las normas; el poder de decisión; y los discursos. Discutimos cómo la auto-representación de la empresa extranjera mediante discursos de responsabilidad social empresarial contrasta con las injusticias ambientales, políticas y sociales que infligen a los habitantes locales, exacerbadas por las políticas nacionales y los acuerdos comerciales internacionales. Por último, argumentamos que las alianzas multi-actoras y multi-escalapueden ofrecer oportunidades para fomentar soluciones ambientales y de justicia social.
Structural basis of response regulator function
Authors: Gao Rong , Bouillet Sophie , Stock Ann
Published: February 2019

Response regulators function as the output components of two-component systems, which couple the sensing of environmental stimuli to adaptive responses. Response regulators typically contain conserved receiver (REC) domains that function as phosphorylation-regulated switches to control the activities of effector domains that elicit output responses. This modular design is extremely versatile, enabling different regulatory strategies tuned to the needs of individual signaling systems. This review summarizes functional features that underlie response regulator function. An abundance of atomic resolution structures and complementary biochemical data have defined the mechanisms for response regulator enzymatic activities, revealed trends in regulatory strategies utilized by response regulators of different subfamilies and provided insights into interactions of response regulators with their cognate histidine kinases. Among the hundreds of thousands of response regulators identified, variations abound. This article provides a framework for understanding structural features that enable function of canonical response regulators and a basis for distinguishing non-canonical configurations.
Polyamines and legumes: Joint stories of stress, nitrogen fixation and environment
Authors: Menéndez Ana B , Calzadilla Pablo I , Sansberro Pedro A , Espasandin Fabiana D , Gazquez Ayelén , Bordenave César D , Maiale Santiago J , Rodríguez Andrés A , Maguire Vanina G , Campestre María P , Garriz Andrés , Rossi Franco R , Romero Fernando M , Solmi Leandro , Salloum Soraya M , Monteoliva Mariela I , Debat Humberto , Ruiz Oscar A
Published: February 2019

Polyamines (PAs) are natural aliphatic amines involved in many physiological processes in almost all living organisms, including responses to abiotic stresses and microbial interactions. This review presents the profuse evidence that relates changes in polyamines levels during responses to biotic and abiotic stresses in model and cultivable species within Leguminosae, and examines their potential roles in the functioning of symbiotic interactions with nitrogen fixing bacteria and arbuscular mycorrhizae. The family Leguminosae constitutes an economically and ecologically key botanical group for humans, being also regarded as the most important protein source for livestock. The ability of legumes to establish symbiotic interactions with nitrogen fixing bacteria and arbuscular mycorrhizae fungi, gives to some legume species that are able to exploit their molecular machinery “pioneer” attributes, with better competition in nutrient-poor soils and higher adaptation to restricted environments. However, many legume crops may be affected by climate change-derived environmental stresses, whereby maintaining their yields safe from adverse environmental conditions is probably one of the biggest challenge facing modern agriculture. Therefore, the obtaining of vigorous genotypes with higher tolerance to abiotic and biotic stressors has turned an increasingly important biotechnological target. At this scenario, PAs can play an important role, and genetic manipulation of crop plants with genes encoding polyamine PA biosynthetic pathway enzymes is envisioned as a strategy to achieve plants with improved stress tolerance and symbiotic performance. As linking plant physiological behavior with "big data" available in "omics" is an essential step to improve our understanding of legumes responses to global change, we also examined integrative MultiOmics approaches available to decrypt the interface legumes-PAs-abiotic and biotic stress or interactions. These approaches are expected to accelerate the identification of stress tolerant phenotypes and the design of new biotechnological strategies to increase their yield and adaptation to marginal environments, making a better use of available plant genetic resources.
Isaac Olsens kopibok som kulturuttrykk på tidlig 1700-tall
Authors: Willumsen Liv Helene
Published: February 2019

Isaac Olsen's Copy Book as a Cultural Expression of the Early Eighteenth Century.This article deals with a copy book written by Isaac Olsen, dating from the early eighteenth century. Isaac Olsen was a teacher and catechist working among the Sami people in the region of Finnmark, Northern Norway. He was a predecessor of the Sami missionary Thomas von Westen. Isaac Olsen left a handwritten copy book of nearly 1000 pages, today preserved in The Museum of Cultural History in Oslo, Norway. The copy book is a compilation of documents related to Isaac Olsen’s work and person. Most of the documents are written in his own hand, but the book also contains documents written by governmental officials such as regional governors and provosts, and even the king in Copenhagen. The article focuses on the voices that may be heard in the texts contained in Isaac Olsen’s copy book: the pedagogical voice, the religious voice, the voice of popular culture, the voices of state officials. Attention is also paid to the contemporary practice of writing and the practice of professional copying. Isaac Olsen’s copy book, which dates from the early 1700s, is seen as a valuable historical source that may give insight into the mental horizon of an individual as well as knowledge about the society in which he lived.
Fire tekststykker knyttet til samemisjonæren Thomas von Westen 1716-1723
Authors: Skjelmo Randi
Published: February 2019

Four Texts Concerning Thomas von Westen's Mission among the Sámi 1716-1723.Thomas von Westen (1682-1727) was responsible for a mission concerning the Sámi population in Norway in the early Eighteenth-Century. The mission was initiated by the Danish-Norwegian King Frederik 4th and the Society for Promoting Lutheran Christianity in Copenhagen 1715. von Westen wrote a significant number of documents concerning the mission. These documents comprise instructions, reports, public correspondence, personal letters and statements. This article concerns four of these texts; a letter to the parish that von Westen worked in when he was appointed leader of missionary work (1716), a letter to the Society for Promoting Lutheran Christianity (1718), the Nærøy manuscript (1723) and finally a letter concerning the establishment of connections to ecclesiastical authorities in Swedish Lapland (1723). Thomas von Westen’s writings reflect his engagement in the mission, his preaching and how he introduced Christianity to the Sámi people by guiding them to personal consciousness and public confession. His documents reflect both his own ambitions and the public interest in the missionary work.
Identification of a novel potassium channel (GiK) as a potential drug target in Giardia lamblia: Computational descriptions of binding sites
Authors: Palomo-Ligas Lissethe , Gutiérrez-Gutiérrez Filiberto , Ochoa-Maganda Verónica Yadira , Cortés-Zárate Rafael , Charles-Niño Claudia Lisette , Castillo-Romero Araceli
Published: February 2019

Background

The protozoan Giardia lamblia is the causal agent of giardiasis, one of the main diarrheal infections worldwide. Drug resistance to common antigiardial agents and incidence of treatment failures have increased in recent years. Therefore, the search for new molecular targets for drugs against Giardia infection is essential. In protozoa, ionic channels have roles in their life cycle, growth, and stress response. Thus, they are promising targets for drug design. The strategy of ligand-protein docking has demonstrated a great potential in the discovery of new targets and structure-based drug design studies.

Methods

In this work, we identify and characterize a new potassium channel, GiK, in the genome of Giardia lamblia. Characterization was performed in silico. Because its crystallographic structure remains unresolved, homology modeling was used to construct the three-dimensional model for the pore domain of GiK. The docking virtual screening approach was employed to determine whether GiK is a good target for potassium channel blockers.

Results

The GiK sequence showed 24–50% identity and 50–90% positivity with 21 different types of potassium channels. The quality assessment and validation parameters indicated the reliability of the modeled structure of GiK. We identified 110 potassium channel blockers exhibiting high affinity toward GiK. A total of 39 of these drugs bind in three specific regions.

Discussion

The GiK pore signature sequence is related to the small conductance calcium-activated potassium channels (SKCa). The predicted binding of 110 potassium blockers to GiK makes this protein an attractive target for biological testing to evaluate its role in the life cycle of Giardia lamblia and potential candidate for the design of novel antigiardial drugs.
Trends in fragmentation and connectivity of Paspalum quadrifarium grasslands in the Buenos Aires province, Argentina
Authors: Gandini Marcelo L. , Lara Bruno D. , Moreno Laura B. , Cañibano Maria A. , Gandini Patricia A.
Published: February 2019

Background

Despite its wide distribution worldwide, only 4.6% of temperate grasslands are included within systems of protected areas. In Argentina, this situation is even more alarming: only 1.05% is protected. The study area (central area of the southern Salado River basin) has a large extent of grasslands of Paspalum quadrifarium (Pq) which has been target since the middle of the last century of a variety of agricultural management practices including fire burning for cattle grazing.

Methods

Five binary images of presence-absence data of Pq from a 42-year range (1974–2016) derived from a land cover change study were used as base data. Morphological Spatial Pattern Analysis (MSPA), Morphological Change Detection (MCD) and Network Connectivity Analysis (NCA) were performed to the data using Guidos Toolbox (GTB) for the estimation of habitat and connectivity dynamics of the Pq patches (fragments).

Results

A loss of the coverage area and habitat nuclei of this grassland was observed during the study period, with some temporal oscillation but no recovery to initial states. Additional drastic reduction in connectivity was also evident in resulting maps. The number of large Pq grassland fragments (>50 ha) decreased at beginning of the study period. Also, fragmentation measured as number of components (patches) was higher at the end of the study period. The Pq pajonal nuclei had their minimum representativeness in 2000, and recovered slightly in area in 2011, but with a significant percentage increase of smaller patches (=islets) and linear elements as bridges and branches. Large corridors (mainly edge of roads) could be observed at the end of the study period, while the total connectivity of the landscape pattern drops continuously. Statistics of links shows mean values decreasing from 1974 to 2016. On the other hand, maximum values of links decreased up to 19% in 2011, and recovered to a 54% of their original value in 2016.

Discussion

Pq fragmentation and habitat reduction could have an impact on the ecosystem functioning and the mobility of some species of native fauna. The connecting elements of the landscape were maintained and/or recovered in percentage in 2011 and 2016. This fact, although favoring the dispersion of the present diversity in the habitat nuclei could cause degradation by an edge effect. Part of the area has the potential to be taken as an area of research and as an example of livestock management, since it is the one that would most preserve the biodiversity of the Pq environment. On the methodological side, the use of a proved tool as GTB is useful for monitoring dynamics of a grassland-habitat fragmentation.
Outdoor Radon Measurements during 2018 in São José dos Campos, Brazil
Authors: Martin Inacio M. , Vilela Douglas C.
Published: February 2019

During 2018 the intensity and its variation in time were monitored, every hour the presence of radon gas in two distinct points near each other in São José dos Campos, Brazil. One point was situated 25 meters high (ACA tower) and the other 3 meters high (ITA laboratory). Two identical RadonEye RD200 (ionization chamber) detectors were used calibrated in picoCurie/liter (pCi/l) or Bequerel/cubic meters (Bq / m3). These measurements indicate that there is always a (day/night) variation in the intensity of the local radon gas presence. With dry and hot periods, there is increasing in radon gas intensity. Intense rains during short period of time, there is also increasing in presence of the radon gas in that site. Fine and continuous rains provoke decrease in the presence of radon gas measured in the place. Comparisons between radon gas intensities per hour with gamma and neutron changes between (0-10) MeV of energy at the same time interval were observed.
mRNA 5′ ends targeted by cytoplasmic recapping cluster at CAGE tags and select transcripts are alternatively spliced
Authors: Berger Mikaela R. , Alvarado Rolando , Kiss Daniel L.
Published: February 2019

Until cytoplasmic recapping was discovered, decapping was thought to irreversibly destine an mRNA to degradation. Contradicting this idea, we readily observe mRNAs targeted by cytoplasmic capping in uncapped, yet stable forms. 5′ rapid amplification of cDNA ends (RACE) shows that nearly all uncapped ends correspond to capped analysis of gene expression tags and that the recapping of ZNF207 mRNA may be restricted to a single splice isoform. Here, a modified RACE approach detected uncapped 5′ RNA ends mapping to 46 mRNAs in cells expressing a dominant negative cytoplasmic capping enzyme and in normal cells. Eleven of 46 cloned mRNAs also contained splice isoform‐limiting sequences. Collectively, these data reinforce earlier work and suggest that alternative splicing may play a role in targeting transcripts for – and/or determining the position of – cytoplasmic capping.
A metabolomic approach to identifying biomarkers in blood of Alzheimer's disease
Authors: Lin Chia‐Ni , Huang Chin‐Chang , Huang Kuo‐Lun , Lin Kun‐Ju , Yen Tzu‐Chen , Kuo Hung‐Chou
Published: February 2019

Objective

This study aims to identify metabolites with altered levels of expression in patients with early and progressive stages of Alzheimer's disease (AD).

Methods

All participants of the study underwent genetic screening and were diagnosed using both neuropsychological assessment and amyloid imaging before metabolome analysis. According to these assessments, the patients were classified as normal (n = 15), with mild cognitive impairment (n = 10), and with AD (n = 15).

Results

Using a targeted metabolomic approach, we found that plasma levels of C3, C5, and C5‐DC acylcarnitines, arginine, phenylalanine, creatinine, symmetric dimethylarginine (SDMA) and phosphatidylcholine ae C38:2 were significantly altered in patients with early and progressive stages of AD. We created a predictive model based on the decision tree that included three main parameters: age, arginine and C5 plasma concentrations. The model distinguished AD patients from other participants with 60% sensitivity and 86.7% specificity. For healthy controls, the sensitivity was 85.7% and specificity was 61.5%. Multivariate ROC analysis to develop a decision tree showed that our model reached moderate diagnostic power in differentiating between older adults who are cognitively normal (AUC = 0.77) and those with AD (AUC = 0.72).

Interpretation

The plasma levels of arginine and valeryl carnitine, together with subject age, are promising as biomarkers for the diagnosis of AD in older adults.
Anti‐PrPC antibody rescues cognition and synapses in transgenic alzheimer mice
Authors: Cox Timothy O. , Gunther Erik C. , Brody A. Harrison , Chiasseu Marius T. , Stoner Austin , Smith Levi M. , Haas Laura T. , Hammersley Jayne , Rees Gareth , Dosanjh Bhupinder , Groves Maria , Gardener Matthew , Dobson Claire , Vaughan Tristan , Chessell Iain , Billinton Andrew , Strittmatter Stephen M.
Published: February 2019

Objective

Amyloid‐beta oligomers (Aßo) trigger the development of Alzheimer's disease (AD) pathophysiology. Cellular prion protein (PrPC) initiates synaptic damage as a high affinity receptor for Aßo. Here, we evaluated the preclinical therapeutic efficacy of a fully human monoclonal antibody against PrPC. This AZ59 antibody selectively targets the Aβo binding site in the amino‐terminal unstructured domain of PrPC to avoid any potential risk of direct toxicity.

Methods

Potency of AZ59 was evaluated by binding to PrPC, blockade of Aβo interaction and interruption of Aβo signaling. AZ59 was administered to mice by weekly intraperitoneal dosing and brain antibody measured. APP/PS1 transgenic mice were treated with AZ59 and assessed by memory tests, by brain biochemistry and by histochemistry for Aß, gliosis and synaptic density.

Results

AZ59 binds PrPC with 100 pmol/L affinity and blocks human brain Aßo binding to PrPC, as well as prevents synaptotoxic signaling. Weekly i.p. dosing of 20 mg/kg AZ59 in a murine form achieves trough brain antibody levels greater than 10 nmol/L. Aged symptomatic APP/PS1 transgenic mice treated with AZ59 for 5–7 weeks show a full rescue of behavioral and synaptic loss phenotypes. This recovery occurs without clearance of plaque pathology or elimination of gliosis. AZ59 treatment also normalizes synaptic signaling abnormalities in transgenic brain. These benefits are dose‐dependent and persist for at least 1 month after the last dose.

Interpretation

Preclinical data demonstrate that systemic AZ59 therapy rescues central synapses and memory function from transgenic Alzheimer's disease pathology, supporting a disease‐modifying therapeutic potential.
Randomized, double‐blind, placebo‐controlled study of interferon‐γ 1b in Friedreich Ataxia
Authors: Lynch David R. , Hauser Lauren , McCormick Ashley , Wells McKenzie , Dong Yi Na , McCormack Shana , Schadt Kim , Perlman Susan , Subramony Sub H. , Mathews Katherine D. , Brocht Alicia , Ball Julie , Perdok Renee , Grahn Amy , Vescio Tom , Sherman Jeffrey W. , Farmer Jennifer M.
Published: February 2019

Objective

In vitro, in vivo, and open‐label studies suggest that interferon gamma (IFN‐γ 1b) may improve clinical features in Friedreich Ataxia through an increase in frataxin levels. The present study evaluates the efficacy and safety of IFN‐γ 1b in the treatment of Friedreich Ataxia through a double‐blind, multicenter, placebo‐controlled trial.

Methods

Ninety‐two subjects with FRDA between 10 and 25 years of age were enrolled. Subjects received either IFN‐γ 1b or placebo for 6 months. The primary outcome measure was the modified Friedreich Ataxia Rating Scale (mFARS).

Results

No difference was noted between the groups after 6 months of treatment in the mFARS or secondary outcome measures. No change was noted in buccal cell or whole blood frataxin levels. However, during an open‐label extension period, subjects had a more stable course than expected based on natural history data.

Conclusions

This study provides no direct evidence for a beneficial effect of IFN‐γ1b in FRDA. The modest stabilization compared to natural history data leaves open the possibility that longer studies may demonstrate benefit.
Experience replay–based output feedback Q‐learning scheme for optimal output tracking control of discrete‐time linear systems
Authors: Rizvi Syed Ali Asad , Lin Zongli
Published: February 2019

This paper focuses on solving the adaptive optimal tracking control problem for discrete‐time linear systems with unknown system dynamics using output feedback. A Q‐learning‐based optimal adaptive control scheme is presented to learn the feedback and feedforward control parameters of the optimal tracking control law. The optimal feedback parameters are learned using the proposed output feedback Q‐learning Bellman equation, whereas the estimation of the optimal feedforward control parameters is achieved using an adaptive algorithm that guarantees convergence to zero of the tracking error. The proposed method has the advantage that it is not affected by the exploration noise bias problem and does not require a discounting factor, relieving the two bottlenecks in the past works in achieving stability guarantee and optimal asymptotic tracking. Furthermore, the proposed scheme employs the experience replay technique for data‐driven learning, which is data efficient and relaxes the persistence of excitation requirement in learning the feedback control parameters. It is shown that the learned feedback control parameters converge to the optimal solution of the Riccati equation and the feedforward control parameters converge to the solution of the Sylvester equation. Simulation studies on two practical systems have been carried out to show the effectiveness of the proposed scheme.
Wearable and Implantable Triboelectric Nanogenerators
Authors: Liu Zhuo , Li Hu , Shi Bojing , Fan Yubo , Wang Zhong Lin , Li Zhou
Published: February 2019

Triboelectric nanogenerators (TENGs) are a promising technology to convert mechanical energy to electrical energy based on coupled triboelectrification and electrostatic induction. With the rapid development of functional materials and manufacturing techniques, wearable and implantable TENGs have evolved into playing important roles in clinic and daily life from in vitro to in vivo. These flexible and light membrane‐like devices have the potential to be a new power supply or sensor element, to meet the special requirements for portable electronics, promoting innovation in electronic devices. In this review, the recent advances in wearable and implantable TENGs as sustainable power sources or self‐powered sensors are reviewed. In addition, the remaining challenges and future possible improvements of wearable and implantable TENG‐based self‐powered systems are discussed.
Hybrid Energy Harvesters: Toward Sustainable Energy Harvesting
Authors: Ryu Hanjun , Yoon Hong‐Joon , Kim Sang‐Woo
Published: February 2019

Recently, sustainable green energy harvesting systems have been receiving great attention for their potential use in self‐powered smart wireless sensor network (WSN) systems. In particular, though the developed WSN systems are able to advance public good, very high and long‐term budgets will be required in order to use them to supply electrical energy through temporary batteries or connecting power cables. This report summarizes recent significant progress in the development of hybrid nanogenerators for a sustainable energy harvesting system that use natural and artificial energies such as solar, wind, wave, heat, machine vibration, and automobile noise. It starts with a brief introduction of energy harvesting systems, and then summarizes the different hybrid energy harvesting systems: integration of mechanical and photovoltaic energy harvesters, integration of mechanical and thermal energy harvesters, integration of thermal and photovoltaic energy harvesters, and others. In terms of the reported hybrid nanogenerators, a systematic summary of their structures, working mechanisms, and output performances is provided. Specifically, electromagnetic induction, triboelectric, piezoelectric, photovoltaic, thermoelectric, and pyroelectric effects are reviewed on the basis of the individual and hybrid power performances of hybrid nanogenerators and their practical applications with various device designs. Finally, the perspectives on and challenges in developing high performance and sustainable hybrid nanogenerator systems are presented.
Boosting Water Dissociation Kinetics on Pt–Ni Nanowires by N‐Induced Orbital Tuning
Authors: Xie Yufang , Cai Jinyan , Wu Yishang , Zang Yipeng , Zheng Xusheng , Ye Jian , Cui Peixin , Niu Shuwen , Liu Yun , Zhu Junfa , Liu Xiaojing , Wang Gongming , Qian Yitai
Published: February 2019

Although it is commonly believed that the water‐dissociation‐related Volmer process is the rate‐limiting step for alkaline hydrogen evolution reaction (HER) on Pt‐based catalysts, the underlying essence, particularly on the atomic scale, still remains unclear. Herein, it is revealed that the sluggish water‐dissociation behavior probably stems from unfavorable orbital orientation and the kinetic issue is successfully resolved via N‐induced orbital tuning. Impressively, N modified Pt–Ni nanowires deliver an ultralow overpotential of 13 mV at 10 mA cm−2, which represents a new benchmark for alkaline HER catalysis. Fine‐structural characterization and density functional theory analysis illustrate that the introduced nitrogen can uniquely modulate the electron densities around the Ni sites, and further create empty dz2 orbitals with superior orientation for water adsorption and activation. More importantly, it is demonstrated that N‐induced orbital modulation can generally boost the alkaline HER activities of Pt–Co, Pt–Ni, and Pt–Cu, offering a new perspective for the design of HER catalysts and beyond.
Electro‐Optic Modulation in Hybrid Metal Halide Perovskites
Authors: Gao Yuan , Walters Grant , Qin Ying , Chen Bin , Min Yimeng , Seifitokaldani Ali , Sun Bin , Todorovic Petar , Saidaminov Makhsud I. , Lough Alan , Tongay Sefaattin , Hoogland Sjoerd , Sargent Edward H.
Published: February 2019

Rapid and efficient conversion of electrical signals to optical signals is needed in telecommunications and data network interconnection. The linear electro‐optic (EO) effect in noncentrosymmetric materials offers a pathway to such conversion. Conventional inorganic EO materials make on‐chip integration challenging, while organic nonlinear molecules suffer from thermodynamic molecular disordering that decreases the EO coefficient of the material. It has been posited that hybrid metal halide perovskites could potentially combine the advantages of inorganic materials (stable crystal orientation) with those of organic materials (solution processing). Here, layered metal halide perovskites are reported and investigated for in‐plane birefringence and linear electro‐optic response. Phenylmethylammonium lead chloride (PMA2PbCl4) crystals are grown that exhibit a noncentrosymmetric space group. Birefringence measurements and Raman spectroscopy confirm optical and structural anisotropy in the material. By applying an electric field on the crystal surface, the linear EO effect in PMA2PbCl4 is reported and its EO coefficient is determined to be 1.40 pm V−1. This is the first demonstration of this effect in hybrid metal halide perovskites, materials that feature both highly ordered crystalline structures and solution processability. The in‐plane birefringence and electro‐optic response reveal that layered perovskite crystals could be further explored for potential applications in polarizing optics and EO modulation.
Manipulate the Electronic and Magnetic States in NiCo2O4 Films through Electric‐Field‐Induced Protonation at Elevated Temperature
Authors: Wang Meng , Sui Xuelei , Wang Yujia , Juan Yung‐Hsiang , Lyu Yingjie , Peng Huining , Huang Tongtong , Shen Shengchun , Guo Chenguang , Zhang Jianbing , Li Zhuolu , Li Hao‐Bo , Lu Nianpeng , N'Diaye Alpha T. , Arenholz Elke , Zhou Shuyun , He Qing , Chu Ying‐Hao , Duan Wenhui , Yu Pu
Published: February 2019

Ionic‐liquid‐gating‐ (ILG‐) induced proton evolution has emerged as a novel strategy to realize electron doping and manipulate the electronic and magnetic ground states in complex oxides. While the study of a wide range of systems (e.g., SrCoO2.5, VO2, WO3, etc.) has demonstrated important opportunities to incorporate protons through ILG, protonation remains a big challenge for many others. Furthermore, the mechanism of proton intercalation from the ionic liquid/solid interface to whole film has not yet been revealed. Here, with a model system of inverse spinel NiCo2O4, an increase in system temperature during ILG forms a single but effective method to efficiently achieve protonation. Moreover, the ILG induces a novel phase transformation in NiCo2O4 from ferrimagnetic metallic into antiferromagnetic insulating with protonation at elevated temperatures. This study shows that environmental temperature is an efficient tuning knob to manipulate ILG‐induced ionic evolution.
Printed Strain Sensors Using Graphene Nanosheets Prepared by Water‐Assisted Liquid Phase Exfoliation
Authors: Manna Kausik , Wang Long , Loh Kenneth J. , Chiang Wei‐Hung
Published: February 2019

A novel approach to leverage the extraordinary properties of graphene for designing thin film strain sensors is demonstrated. Graphene nanosheets (GNS) are produced from graphite by a liquid phase exfoliation (LPE) method using water along with N‐methylpyrrolidinone (NMP) as cosolvents. It is found that the water‐NMP solvent system enhances the exfoliation yield and the stability of the GNS dispersion, thereby lowering the number of defects in the GNS basal plane. Both LPE‐based GNS and reduced graphene oxide (RGO) are synthesized for fabricating thin film strain sensors and for comparison purposes. Detailed micro‐Raman, X‐ray photoelectron spectroscopy, and transmission electron microscopy studies indicate that the as‐produced GNS exhibits lower defects than RGO nanosheets. The strain sensing study reveals that strain sensors fabricated using low‐defect GNS exhibit enhanced electrical and electromechanical properties, including higher electrical conductivity, lower noise floor, and more stable electromechanical response as compared to RGO‐based sensors.
Rational Design of Soft, Thermally Conductive Composite Liquid‐Cooled Tubes for Enhanced Personal, Robotics, and Wearable Electronics Cooling
Authors: Kotagama Praveen , Phadnis Akshay , Manning Kenneth C. , Rykaczewski Konrad
Published: February 2019

Thermoregulatory garments composed of liquid‐cooled plastic tubes have users ranging from astronauts to multiple sclerosis patients and are emerging as a flexible cooling solution for wearable electronics and high‐power robotics. Despite the plethora of applications, the current cooling systems are cumbersome to use due to their excessive size. In this work this issue is resolved by developing soft, thermally conductive silicone–aluminum composite tubes. To achieve optimal device performance, the material must be designed to balance the decrease in bulk thermal resistance and the increase in interfacial tube‐substrate resistance due to composite stiffening. Thus, to enable the rational design of such tubes, a closed form thermomechanical model that predicts cooling performance as a function of tube geometry and filler fraction is developed and experimentally validated. Predictions via this model and experiments are used to reveal how the tube's geometrical and material design can be adjusted to minimize the required length of tubing and maximize the heat extracted from a metallic surface and skin. Lastly, through a holistic analysis, this work demonstrates that besides significantly increasing overall cooling capability, the use of low‐resistance tubing can provide a multifold reduction in the cooling system size and enable novel operating modes.
Measuring gas hold‐up in gas–liquid/gas–solid–liquid stirred tanks with an electrical resistance tomography linear probe
Authors: Forte Giuseppe , Alberini Federico , Simmons Mark J. H. , Stitt E. Hugh
Published: February 2019

An electrical resistance tomography (ERT) linear probe was used to measure gas hold‐up in a two‐phase (gas–liquid) and three phase (gas–solid–liquid) stirred‐tank system equipped with a Rushton turbine. The ERT linear probe was chosen rather than the more commonly used ring cage geometry to achieve higher resolution in the axial direction as well as its potential for use on manufacturing plant. Gas‐phase distribution was measured as a function of flow regime by varying both impeller speed and gas flow rate. Global and local gas hold‐up values were calculated using ERT data by applying Maxwell's equation for conduction through heterogeneous media. The results were compared with correlations, hard‐field tomography data, and computational fluid dynamic simulations available in the literature, showing good agreement. This study thus demonstrates the capability of ERT using a linear probe to offer, besides qualitative tomographic images, reliable quantitative data regarding phase distribution in gas–liquid systems.
Epigenetics and genomics in Turner syndrome
Authors: Viuff Mette , Skakkebæk Anne , Nielsen Morten M. , Chang Simon , Gravholt Claus H.
Published: February 2019

The pathogenesis of Turner syndrome (TS) and the genotype–phenotype relationship has been thoroughly investigated during the last decade. It has become evident that the phenotype seen in TS does not only depend on simple gene dosage as a result of X chromosome monosomy. The origin of TS specific comorbidities such as infertility, cardiac malformations, bone dysgenesis, and autoimmune diseases may depend on a complex relationship between genes as well as transcriptional and epigenetic factors affecting gene expression across the genome. Furthermore, two individuals with TS with the exact same karyotype may exhibit completely different traits, suggesting that no conventional genotype–phenotype relationship exists. Here, we review the different genetic mechanisms behind differential gene expression, and highlight potential key‐genes essential to the comorbidities seen in TS and other X chromosome aneuploidy syndromes. KDM6A, important for germ cell development, has shown to be differentially expressed and methylated in Turner and Klinefelter syndrome across studies. Furthermore, TIMP1/TIMP3 genes seem to affect the prevalence of bicuspid aortic valve. KDM5C could play a role in the neurocognitive development of Turner and Klinefelter syndrome. However, further research is needed to elucidate the genetic mechanism behind the phenotypic variability and the different phenotypic traits seen in TS.
The impact of somatic mosaicism on bicuspid aortic valve and aortic dissection in Turner Syndrome
Authors: Prakash Siddharth K.
Published: February 2019

Somatic mosaicism is a major modifier of turner syndrome (TS) features and may be more prevalent than once thought, as new molecular techniques enable detection of tissue‐specific mosaicism. This review explores the causes of mosaicism, discusses how mosaicism may impact congenital aortic defects in TS, and summarizes molecular methods to detect mosaicism in different contexts.
How bearded capuchin monkeys (Sapajus libidinosus) prepare to use a stone to crack nuts
Authors: Fragaszy Dorothy M. , Morrow Kristen S. , Baldree Rhianna , Unholz Emily , Izar Patricia , Visalberghi Elisabetta , Haslam Michael
Published: February 2019

Bearded capuchin monkeys crack nuts with naturally varying stone hammers, suggesting they may tune their grips and muscular forces to each stone. If so, they might use discrete actions on a stone before lifting and striking, and they would likely use these actions more frequently when the stone is larger and/or less familiar and/or when first initiating striking. We examined the behavior of (a) four monkeys (all proficient at cracking nuts) with two larger (1 kg) and two smaller (0.5 kg) stones, (b) 12 monkeys with one 1 kg stone, and (c) one monkey during its first 100 strikes with an initially unfamiliar 1 kg stone. Bearded capuchin monkeys used three discrete actions on the stone before striking, all more often with the larger stones than the smaller stones. We infer that the first discrete action (Spin) aided the monkey in determining where to grip the stone, the second (Flip) allowed it to position the stone on the anvil ergonomically before lifting it, and the third (Preparatory Lift) readied the monkey for the strenuous lifting action. The monkey that provided 100 strikes with one initially unfamiliar stone performed fewer Spins in later strikes but performed Flip and Preparatory Lift at consistent rates. The monkeys gripped the stone with both hands along the sides to lift it, but usually moved one or both hands to the top of the stone at the zenith of the lift for the downward strike. The findings highlight two new aspects of the capuchins’ nut‐cracking: (a) Anticipatory actions with the stone before striking, especially when the stone is larger or unfamiliar, and when initiating striking and (b) shifting grips on the stone during a strike. We invite researchers to investigate if other taxa use anticipatory actions and shift their grips during percussive activity.
Validating camera trap distance sampling for chimpanzees
Authors: Cappelle Noémie , Després‐Einspenner Marie‐Lyne , Howe Eric J. , Boesch Christophe , Kühl Hjalmar S.
Published: February 2019

The extension of distance sampling methods to accommodate observations from camera traps has recently enhanced the potential to remotely monitor multiple species without the need of additional data collection (sign production and decay rates) or individual identification. However, the method requires that the proportion of time is quantifiable when animals can be detected by the cameras. This can be problematic, for instance, when animals spend time above the ground, which is the case for most primates. In this study, we aimed to validate camera trap distance sampling (CTDS) for the semiarboreal western chimpanzee (Pan troglodytes verus)in Taï National Park, Côte d'Ivoire by estimating abundance of a population of known size and comparing estimates to those from other commonly applied methods. We estimated chimpanzee abundance using CTDS and accounted for limited availability for detection (semiarboreal). We evaluated bias and precision of estimates, as well as costs and efforts required to obtain them, and compared them to those from spatially explicit capture‐recapture (SECR) and line transect nest surveys. Abundance estimates obtained by CTDS and SECR produced a similar negligible bias, but CTDS yielded a larger coefficient of variation (CV = 39.70% for CTDS vs. 1%/19% for SECR). Line transects generated the most biased abundance estimates but yielded a better coefficient of variation (27.40–27.85%) than CTDS. Camera trap surveys were twice more costly than line transects because of the initial cost of cameras, while line transects surveys required more than twice as much time in the field. This study demonstrates the potential to obtain unbiased estimates of the abundance of semiarboreal species like chimpanzees by CTDS.

HIGHLIGHTS

Camera trap distance sampling produced accurate density estimates for semiarboreal chimpanzees.

Availability for detection must be accounted for and can be derived from the activity pattern.
Balancing contest competition, scramble competition, and social tolerance at feeding sites in wild common marmosets (Callithrix jacchus)
Authors: De la Fuente María Fernanda , Schiel Nicola , Bicca‐Marques Júlio César , Caselli Christini B. , Souto Antonio , Garber Paul A.
Published: February 2019

Models of primate sociality focus on the costs and benefits of group living and how factors such as rank, feeding competition, alliance formation, and cooperative behavior shape within‐group social relationships. We conducted a series of controlled field experiments designed to investigate how resource distribution (one or three of four reward platforms) and amount of food on a reward platform affected foraging strategies and individual feeding success in four groups of wild common marmosets (Callithrix jacchus) living in the Caatinga of northeastern Brazil. At our field site, common marmoset groups are characterized by a single breeding female who can produce twin litters twice per year, strong social cohesion, and cooperative infant care provided principally by several adult male helpers. We found that except for the dominant breeding female, rank (based on aggression) was not a strong predictor of feeding success. Although the breeding female in each group occupied the highest rank position and obtained the greatest daily feeding success, all other group members, including adults and juveniles experienced relatively equal feeding success across most experimental conditions. This was accomplished using a balance of behavioral strategies related to contest competition, scramble competition (associated with a finder's advantage), and social tolerance (sharing the same feeding platform). Based on these results, the social structure of common marmosets is best described as “single female dominance,” with the breeding female maximizing food intake needed to offset the energetic costs associated with reproductive twinning and the ability to produce two litters per year. Cooperative infant caregiving, in which the number of helpers is positively correlated with offspring survivorship, requires a set of behavioral strategies that serve to reduce contest competition and promote prosocial behaviors at feeding sites.
Palladium‐katalysierte intermolekulare Aryliodierung von internen Alkinen
Authors: Lee Yong Ho , Morandi Bill
Published: February 2019

Eine vollständig atomökonomische, Palladium‐katalysierte Additionsreaktion wurde entwickelt, um einen stereoselektiven Zugang zu funktionalisierten, vierfach substituierten Alkenyliodiden zu erhalten. Der Palladiumkatalysator weist einen elektronenarmen, zweizähnigen Liganden auf, der zwar selten in der Katalyse verwendet wird, aber essentiell ist, um diese chemoselektive, intermolekulare Reaktion eines Alkins mit einem Aryliodid in äquimolaren Mengen mit hoher Ausbeute ablaufen zu lassen. Diese neue Carbohalogenierungsreaktion ist eine attraktive Alternative zu bisherigen Synthesemethoden, welche auf mehrstufige Synthesesequenzen mit Schutzgruppenmanipulationen basieren.
Lipid Heterogeneity between Astrocytes and Neurons Revealed by Single‐Cell MALDI‐MS Combined with Immunocytochemical Classification
Authors: Neumann Elizabeth K. , Comi Troy J. , Rubakhin Stanislav S. , Sweedler Jonathan V.
Published: February 2019

Transcriptomics characterizes cells based on their potential molecular repertoire whereas direct mass spectrometry (MS) provides information on the actual compounds present within cells. Single‐cell matrix‐assisted laser desorption/ionization (MALDI) MS can measure the chemical contents of individual cells but spectra are difficult to correlate to conventional cell types, limiting the metabolic information obtained. We present a protocol that combines MALDI‐MS with immunocytochemistry to assay over a thousand individual rat brain cells. The approach entwines the wealth of knowledge obtained by immunocytochemical profiling with mass spectral information on the predominant lipids within each cell. While many lipid species showed a high degree of similarity between neurons and astrocytes, seventeen significantly differed between the two cell types, including four phosphatidylethanolamines elevated in astrocytes and nine phosphatidylcholines in neurons.
Selective [5,5]‐Sigmatropic Rearrangement by Assembly of Aryl Sulfoxides with Allyl Nitriles
Authors: Zhang Lei , He Jia‐Ni , Liang Yuchen , Hu Mengjie , Shang Li , Huang Xin , Kong Lichun , Wang Zhi‐Xiang , Peng Bo
Published: February 2019

Aromatic [5,5]‐sigmatropic rearrangement is an appealing protocol for accessing 1,4‐substituted arenes. However, such a protocol has not been well utilized in organic synthesis because of the difficulties in the synthesis of the substrates, selectivity issues, and limited substrate scope. Described herein is a new [5,5]‐sigmatropic reaction utilizing readily available aryl sulfoxides and allyl nitriles. This reaction features mild reaction conditions, high chemo‐ and regioselectivity, excellent functional‐group compatibility, and broad substrate scope. Computational studies suggest that the success of the reaction can be attributed to the selective electrophilic assembly of the rearrangement precursors, in which a linear ‐C=C=N‐ linkage favors [5,5]‐sigmatropic rearrangement over the competitive [3,3]‐sigmatropic rearrangement.
Engineering Polymer‐Binding Bispecific Antibodies for Enhanced Pretargeted Delivery of Nanoparticles to Mucus‐Covered Epithelium
Authors: Huckaby Justin T. , Parker Christina L. , Jacobs Tim M. , Schaefer Alison , Wadsworth Daniel , Nguyen Alexander , Wang Anting , Newby Jay , Lai Samuel K.
Published: February 2019

Mucus represents a major barrier to sustained and targeted drug delivery to mucosal epithelium. Ideal drug carriers should not only rapidly diffuse across mucus, but also bind the epithelium. Unfortunately, ligand‐conjugated particles often exhibit poor penetration across mucus. In this work, we explored a two‐step “pretargeting” approach through engineering a bispecific antibody that binds both cell‐surface ICAM‐1 and polyethylene glycol (PEG) on the surface of nanoparticles, thereby effectively decoupling cell targeting from particle design and formulation. When tested in a mucus‐coated Caco‐2 culture model that mimics the physiological process of mucus clearance, pretargeting increased the amount of PEGylated particles binding to cells by around 2‐fold or more compared to either non‐targeted or actively targeted PEGylated particles. Pretargeting also markedly enhanced particle retention in mouse intestinal tissues. Our work underscores pretargeting as a promising strategy to improve the delivery of therapeutics to mucosal surfaces.