bluuebunny/crossref_metadata_2025 huggingface dataset:
Distribution and abundance of muskoxen (Ovibos moschatus) and Peary caribou (Rangifer tarandus pearyi) on Graham, Buckingham, and southern Ellesmere islands, March 2015
Authors: Anderson Morgan , Kingsley Michael C.S.
Published: November 2017

We flew a survey of southern Ellesmere Island, Graham Island, and Buckingham Island in March 2015 to obtain estimates of abundance for muskoxen and Peary caribou. Generally, muskoxen were abundant north of the Sydkap Ice Cap along Baumann Fiord, north of Goose Fiord, west and north of Muskox Fiord, and on the coastal plains and river valleys east of Vendom Fiord. Although few, they were also present on Bjorne Peninsula and the south coast between the Sydkap Ice Cap and Jakeman Glacier. We observed a total of 1146 muskoxen. Calves (approximately 10-months old) made up 22% of the observed animals. The population estimate was 3200 ± 602 SE (standard error) muskoxen, the highest muskox population size ever estimated for southern Ellesmere, Graham and Buckingham islands. This could be because previous efforts typically surveyed only a portion of our area or focused elsewhere, or the results were provided only as minimum counts rather than estimates of abundance. Regardless, our results indicate that the muskox population has recovered from low levels in 2005 of 312-670 (95% confidence interval [CI]) individuals. Peary caribou abundance appears to be low.  We only saw 38 Peary caribou during our 2015 survey. This confounds appraisal of possible abundance change since 2005, when 109-442 caribou (95% CI) were estimated to inhabit the same surveyed area. We estimated 183 ± 128 SE Peary caribou, and suggest that their numbers are likely stable at low density on southern Ellesmere Island.
Genome-widein silicoidentification of membrane-bound transcription factors in plant species
Authors: Yao Shixiang , Deng Lili , Zeng Kaifang
Published: November 2017

Membrane-bound transcription factors (MTFs) are located in cellular membranes due to their transmembrane domains. In plants, proteolytic processing is considered to be the main mechanism for MTF activation, which ensures the liberation of MTFs from membranes and further their translocation into the nucleus to regulate gene expression; this process skips both the transcriptional and translational stages, and thus it guarantees the prompt responses of plants to various stimuli. Currently, information concerning plant MTFs is limited to model organisms, includingArabidopsis thalianaandOryza sativa, and little is known in other plant species at the genome level. In the present study, seven membrane topology predictors widely used by the research community were employed to establish a reliable workflow for MTF identification. Genome-widein silicoanalysis of MTFs was then performed in 14 plant species spanning the chlorophytes, bryophytes, gymnosperms, monocots and eudicots. A total of 1,089 MTFs have been identified from a total of 25,850 transcription factors in these 14 plant species. These MTFs belong to 52 gene family, and the top six most abundant families are the NAC (128), SBP (77), C2H2 (70), bZIP (67), MYB-related (65) and bHLH (63) families. The MTFs have transmembrane spans ranging from one to thirteen, and 71.5% and 21.1% of the MTFs have one and two transmembrane motifs, respectively. Most of the MTFs in this study have transmembrane motifs located in either N- or C-terminal regions, indicating that proteolytic cleavage could be a conserved mechanism for MTF activation. Additionally, approximately half of the MTFs in the genome of eitherArabidopsis thalianaorGossypium raimondiicould be potentially regulated by alternative splicing, indicating that alternative splicing is another conserved activation mechanism for MTFs. The present study performed systematic analyses of MTFs in plant lineages at the genome level, and provides invaluable information for the research community.
Temperature and dissolved oxygen stratification in the lake Rudrasagar: Preliminary investigations
Authors: Pal Mihir Pal , Samal Nihar R. , Roy Pankaj k. Roy , Roy Malabika B.
Published: November 2017

Temperature drives the major physico-chemical and biological actions in inland water bodies. The higher the water temperature, the greater the biogeochemical activity influenced by the environmental intrinsic and extrinsic parameters. Temperature also controls the dynamics of sustainability of various aquatic organisms that live in lakes and reservoirs, though higher life forms, such as fish, insects, zooplankton, phytoplankton, and other aquatic species all have a recommended temperature variety. The increase in water temperature due to the increase in atmospheric air temperature results in lake water column stratification and the dissolved oxygen level variation in aquatic systems are greatly affected. The vertical distributions of dissolved oxygen in the water column are highly dependent due to change in vertical temperature gradient. In the present paper, an effort has been made to investigate the impact of temperature stratification on dissolved oxygen variability in the Rudrasagar, a natural lake in western Tripura. The changes in dissolved oxygen distribution in this natural lake will give us an idea of regional lake health condition and will also establish the need of further large scale research concerning the development of a biophysical-coupled model.   Keywords: Thermal stratification, Dissolved Oxygen, Thermocline, Rudrasagar Lake, Hypolimnion
Limnological Comparisons of Threats to Aquatic Life Owing to Thermal Stratification in two Morphometrically Different Urban Shallow Lakes
Authors: Samal Nihar R. , Roy Pankaj K. , Roy Malabika B. , Mazumdar Asis Mazumdar
Published: November 2017

A minimum value in the Dissolved Oxygen distribution of two shallow lakes namely, Rabindra Sarobar in south Kolkata and Subhas Sarobar in East Kolkata in the Gangetic Delta plain, has been observed to develop in the Hypolimnion during the stratified period. This minimum is usually explained by the accumulation of organic matter from the overlying layer of water. The introduction of organic matter from allochthonous and autochthonous sources is also a likely contributor to the accelerated oxygen depletion within Hypolimnion. The thermal stratification, in general, which occurs in these tropical lakes, is of direct relevance in maintaining the water quality standards, particularly for higher aquatic life. The present article attempts to investigate the possible depletion of hypolimnetic oxygen depletion as a result of the impact of thermal stratification.  These investigations will be the basic guidelines for the fishermen and their livelihoods potentially depend upon the different varieties of fishing on daily basis. The massive summer fish kills in these lakes is a major devastating happenings that is reported by the fishermen and also it is well evident from our experimental observations.  The comparison of the biodiversity of these two lakes is attempted in the present investigation. Key Words: Thermal stratification, Dissolved Oxygen, Tropical Shallow Lake, Hypolimnion, biodiversity
La educación e interpretación ambiental en las áreas silvestres protegidas del estado: La experiencia del Parque Nacional Conguillío (Región de La Araucanía) para fomentar la conservación en los visitantes.
Authors: González Marilyn , Gutiérrez Eleodoro , Inaipil Carlos , Peña Jorge
Published: November 2017

Dentro de las Áreas Silvestres protegidas de la Región de la Araucanía, sur de Chile, se destaca el Parque Nacional Conguillío inserto en la precordillera andina. Considerado un área de gran importancia ecosistémica dada la diversidad de ambientes que presenta producto de la acción vulcanológica propia de esta cordillera, ésta unidad conforma parte del selecto grupo de Reserva de la Biosfera del país. En él es posible encontrar ecosistemas de bosque primario de Araucaria, humedales (incluyendo ríos, lagos y esteros), escoriales y altas cumbres como es el Volcán LLaima y Sierra Nevada, todas de importante valor científico, geológico, geomorfológico y turístico. Su alta concurrencia por sus atractivos escénicos, flora y fauna, generan una importante llegada de visitantes, nacionales y extranjeros especialmente en época estival dado las mejores condiciones metereológicas y la temporada de vacaciones. Es por ésta razón, que el programa de educación e interpretación ambiental creado pioneramente hace 44 años y actualmente vigente como actividades para sus visitantes adultos y niño(a)s, cobra un mayor sentido de pertenencia para el visitante a través de una experiencia en un ASPE. Las actividades como experiencia, buscan la generación de nuevas actitudes que involucren una conducta del visitante orientada a la sostenibilidad del parque y la apreciación del entorno natural como parte fundamental en el desarrollo del ser humano. En este contexto, el programa actual muestra un crecimiento sostenido de un 7% en número de visitantes entre temporada 2013-2014, siendo objetivo de este trabajo el mostrar antecedentes generales del parque, los senderos más visitados, las especies de flora y fauna más atractivas y/o con problemas de conservación, así como el programa en cuanto a las actividades y sus proyecciones de mejora. Palabras clave: educación ambiental, flora, fauna.
Proyecto botánica forense: las ciencias agronómicas más allá de la agronomía.
Authors: Cofré González Ximena , Valdivia Moraga Margarita Valdivia Moraga
Published: November 2017

[Carta al editor sobre la situación de la botánica forense y sus implicancias científicas]
Observations on Phallocryptus Spinosa (Branchiopoda, Anostraca) Populations from the high Plateaus of Northeastern Algeria
Authors: Amarouayache Mounia
Published: November 2017

Phallocryptus spinosa (Thamnocephalidae) is a small primitive crustacean which lives in temporary saline pools of the Palaearctic region called Chott, Sebkha, Garâa or Daya in North Africa. Data on its biology and life history are very scarce despite its ecological importance in wetlands. Four populations living in the Northeastern High Plateaus of Algeria, Garâas Guellif, El-Tarf, Ank Djemel and Sebkha Ez-Zemoul, have been studied in point of view of their morphmetry (13 parameters) and their reproduction. The population of Sebkha Ez-Zemoul, living in higher salinities and in sympatry with Artemia salina was different from the 3 other populations that are close together. Its adults are the largest (21.77 ± 2.34 mm and 23.65 ± 2.36 mm for males and females respectively) and produce more cysts 771.47±8.45 cysts/brood of 293.11±10.41 µm diameter. Associated carcinological fauna and some behavioral traits are also approached.
Environmental changes on freshwater fish communities in South America in the last five decades: a case study in northeast Argentina.
Authors: Volpedo Alejandra
Published: November 2017

Environmental changes together with other stressors, such as habitat destruction, may cause widespread extinctions, decrease in biodiversity and disrupt natural communities, resulting in novel species assemblages. South America has a large diversity of freshwater fishes with complex evolutionary histories, mainly due to the presence of a wide variety of aquatic environments. Argentina has experienced an increase in rainfall in the last five decades leading to important climatic and hydrological changes. These changes caused the displacement of the isohyets towards the west. This study reports changes in the composition of freshwater fishes in northeast Argentina during the last five decades, and investigated a causal relationship between the variation in fish assemblages and climate change.The changes in the distribution and composition of fish communities between 1962 and 2010 were analyzed in 22 stations. These stations were agrouped in relation to the ichthyogeographic provinces: Great Rivers province (GRp) and Pampean province (Pp). The correlation between rainfall in relation to the number total species from each of the studied provinces showed a significant positive correlation in Pp and not correlation in GRp. The annual mean river discharge and the number of total species from each ecoregion showed a significant positive correlation in GRp, and not correlation in Pp. The results of this study strongly suggest that the rainfall variations and river discharges observed in northeast Argentina induced changes in the composition of fish assemblages that lead to the redistribution of fish species among ichthyogeographic provinces.
STUDY OF VARIABILITY OF RAINFALL AND SUITABILITY OF FARMING IN SUB- HUMID REGION: A CASE STUDY OF JAIPUR DISTRICT, RAJASTHAN, INDIA
Authors: Meena Arjun Lal , Bisht Priyanka
Published: November 2017

Agricultural activities are integrated with climatic conditions and elements such as temperature, humidity, rainfall etc. Rainfall is the prominent feature of climate which directly or indirectly influences agricultural activities. The rainfall patterns and its erratic characteristics has been created problem for farmer as every year its pattern gets change. In India, more than 70% people rely on agriculture and allied activities for their survival. The farming totally depends on rainfall distribution and intensity as farmers are not aware about new technology and methods. This paper is attempted to demonstrate the rainfall variability in Jaipur district, which is situated in sub-humid region of Rajasthan.
III‐Nitride Light‐Emitting Diodes
Authors: Ding Kai , Avrutin Vitaliy , Özgür Ümit , Morkoç Hadis
Published: November 2017

III‐Nitride light‐emitting diodes (LEDs) are luminescent p–n junction devices composed of stacked groupIII‐nitride semiconductor epitaxial layers with modulated groupIIIelement composition and dopant concentration. As new processing techniques onIII‐nitrides are constantly emerging, the luminescence efficiency ofIII‐nitrideLEDs in the visible range has already surpassed traditional fluorescent lamps in the last decade. Their applications expand from signs, displays, and traffic lights to general solid‐state lighting. Fabrication ofIII‐nitrideLEDs has become an essential part of modern semiconductor industry. In this article, we start by introducing the fundamentals and physics ofIII‐nitrideLEDs, and then we review the key challenges and solution strategies for the realization of high‐brightnessIII‐nitrideLEDs in visible and ultraviolet (UV) spectral ranges, with a focus on the epitaxial growth of film materials by using the metalorganic chemical vapor deposition (MOCVD). The research trends in the latest years and a perspective on the future ofIII‐nitrideLEDs, especially on more efficient green andUVLEDs including those with boron nitride (BN), are also discussed.
Ambient Intelligence: A Perspective of Granular Computing
Authors: Loia Vincenzo , Gaeta Angelo , Orciuoli Francesco
Published: November 2017

Ambient intelligence (AmI) is an user‐centric multidisciplinary paradigm that grounds its origins in the works of Wiser and Norman on ubiquitous and disappearing computing. Basically, it refers to adding intelligence in devices to make our surrounding environment sensitive, responsive, adaptive, and smart. An important feature that AmI applications need to achieve is the capability of applying human representations and reasoning. Humans represent the reality with hierarchies and abstractions, look at real problems from different perspectives, analyze a cognitive target with capabilities of granulation. Granular computing (GrC) is a suitable paradigm to design and develop AmI systems with capabilities of human representations, reasoning, and decision‐making. In this article, we offer an overview of how current GrC results are positioned with respect to the enabling technologies of AmI, and present a comprehensive view of how GrC can enforce AmI with human‐oriented perception, representation, reasoning, and decision‐making. This comprehensive view is based on a new computational model, namely, the Granular situation awareness.
Concentrator Photovoltaic Systems: Introduction
Authors: Nishioka Kensuke , Ota Yasuyuki
Published: November 2017

One way to address the problem of cost and shortage of semiconductor materials in photovoltaic systems is to employ concentrator systems, which focus sunlight with optics, such as lenses and mirrors, thereby increasing the intensity of sunlight incident on a solar cell. A typical concentrator photovoltaic (
CPV
) system is composed of a solar cell, optics, and a tracker. The primary reason for using concentrators is to decrease the area of the solar cell material being used in a system, because solar cells are an expensive component of photovoltaic systems. Replacing the semiconductor solar cell area with lower cost plastic lenses reduces the overall system cost. For a concentrator module, the solar cell area is a small fraction of the total module area. Although high‐efficiency solar cells using
III
–
V
compound semiconductors are more expensive than classic solar cells, if the concentration level is sufficiently high and the optics components are affordable, the final system becomes cost‐competitive. Moreover, as a merit of concentrator systems, the conversion efficiency of the cells increases. In order to maintain high efficiency of
CPV
systems in outdoor operations, various technologies, such as antisoiling and reduction of the cell temperature, should be developed. Herein, the basic concepts and recent technologies of
CPV
are described.
Fuzzy Measures
Authors: Torra Vicenç
Published: November 2017

Fuzzy measures, also known as non‐additive measures, capacities and monotonic games, have appeared in different contexts as a way to express interaction between objects. They are also a generalization of standard additive measures. In this article we present an overview of these measures. We present their definition and the most relevant families of fuzzy measures. Fuzzy measures are often used in combination with fuzzy integrals (namely the Choquet and Sugeno integrals). We will also review the definition of these integrals and describe representative applications of fuzzy measures.
Polyketones: Synthesis and Applications
Authors: Vavasori Andrea , Ronchin Lucio
Published: November 2017

Polyketones, also known as aliphatic polyketone, are a relatively new class of polymers obtained by the perfectly alternating copolymerization or terpolymerization of α‐olefins with carbon monoxide. The polymerization is well catalyzed by Pd(II) complexes; the activity of which strongly depends by the nature of the ligand, promoting agents, and solvent used. Owing to their excellent mechanical properties, thermoplastic polyketones have found diverse industrial applications ranging from fibers, fire‐retardant materials, and film coatings to membranes, packaging materials, and adhesives. Herein, we review the synthesis, properties, and applications of polyketones. In addition, industrial production of polyketone is also discussed.
Detecting Upward Directed Charged Particle Fluxes in the Mars Science Laboratory Radiation Assessment Detector
Authors: Appel J. K. , Köehler J. , Guo J. , Ehresmann B. , Zeitlin C. , Matthiä D. , Lohf H. , Wimmer‐Schweingruber R. F. , Hassler D. , Brinza D. E. , Böhm E. , Böttcher S. , Martin C. , Burmeister S. , Reitz G. , Rafkin S. , Posner A. , Peterson J. , Weigle G.
Published: November 2017

The Mars Science Laboratory rover Curiosity, operating on the surface of Mars, is exposed to radiation fluxes from above and below. Galactic Cosmic Rays travel through the Martian atmosphere, producing a modified spectrum consisting of both primary and secondary particles at ground level. These particles produce an upward directed secondary particle spectrum as they interact with the Martian soil. Here we develop a method to distinguish the upward and downward directed particle fluxes in the Radiation Assessment Detector (RAD) instrument, verify it using data taken during the cruise to Mars, and apply it to data taken on the Martian surface. We use a combination of Geant4 and Planetocosmics modeling to find discrimination criteria for the flux directions. After developing models of the cruise phase and surface shielding conditions, we compare model‐predicted values for the ratio of upward to downward flux with those found in RAD observation data. Given the quality of available information on Mars Science Laboratory spacecraft and rover composition, we find generally reasonable agreement between our models and RAD observation data. This demonstrates the feasibility of the method developed and tested here. We additionally note that the method can also be used to extend the measurement range and capabilities of the RAD instrument to higher energies.
Intermediate‐Scale Experimental Study to Improve Fundamental Understanding of Attenuation Capacity for Leaking CO2 in Heterogeneous Shallow Aquifers
Authors: Plampin Michelle R. , Porter Mark L. , Pawar Rajesh J. , Illangasekare Tissa H.
Published: November 2017

To assess the risks of Geologic Carbon Sequestration (GCS), it is crucial to understand the fundamental physicochemical processes that may occur if and when stored CO2 leaks upward from a deep storage reservoir into the shallow subsurface. Intermediate‐scale experiments allow for improved understanding of the multiphase evolution processes that control CO2 migration behavior in the subsurface, because the boundary conditions, initial conditions, and porous media parameters can be better controlled and monitored in the laboratory than in field settings. For this study, a large experimental test bed was designed to mimic a cross section of a shallow aquifer with layered geologic heterogeneity. As water with aqueous CO2 was injected into the system to mimic a CO2‐charged water leakage scenario, the spatiotemporal evolution of the multiphase CO2 plume was monitored. Similar experiments were performed with two different sand combinations to assess the relative effects of different types of geologic facies transitions on the CO2 evolution processes. Significant CO2 attenuation was observed in both scenarios, but by fundamentally different mechanisms. When the porous media layers had very different permeabilities, attenuation was caused by local accumulation (structural trapping) and slow redissolution of gas phase CO2. When the permeability difference between the layers was relatively small, on the other hand, gas phase continually evolved over widespread areas near the leading edge of the aqueous plume, which also attenuated CO2 migration. This improved process understanding will aid in the development of models that could be used for effective risk assessment and monitoring programs for GCS projects.
Cartograms Facilitate Communication of Climate Change Risks and Responsibilities
Authors: Döll Petra
Published: November 2017

Communication of climate change (CC) risks is challenging, in particular if global‐scale spatially resolved quantitative information is to be conveyed. Typically, visualization of CC risks, which arise from the combination of hazard, exposure and vulnerability, is confined to showing only the hazards in the form of global thematic maps. This paper explores the potential of contiguous value‐by‐area cartograms, that is, distorted density‐equalizing maps, for improving communication of CC risks and the countries' differentiated responsibilities for CC. Two global‐scale cartogram sets visualize, as an example, groundwater‐related CC risks in 0.5° grid cells, another one the correlation of (cumulative) fossil‐fuel carbon dioxide emissions with the countries' population and gross domestic product. Viewers of the latter set visually recognize the lack of global equity and that the countries' wealth has been built on harmful emissions. I recommend that CC risks are communicated by bivariate gridded cartograms showing the hazard in color and population, or a combination of population and a vulnerability indicator, by distortion of grid cells. Gridded cartograms are also appropriate for visualizing the availability of natural resources to humans. For communicating complex information, sets of cartograms should be carefully designed instead of presenting single cartograms. Inclusion of a conventionally distorted map enhances the viewers' capability to take up the information represented by distortion. Empirical studies about the capability of global cartograms to convey complex information and to trigger moral emotions should be conducted, with a special focus on risk communication.
Observations Directly Linking Relativistic Electron Microbursts to Whistler Mode Chorus: Van Allen Probes and FIREBIRD II
Authors: Breneman A. W. , Crew A. , Sample J. , Klumpar D. , Johnson A. , Agapitov O. , Shumko M. , Turner D. L. , Santolik O. , Wygant J. R. , Cattell C. A. , Thaller S. , Blake B. , Spence H. , Kletzing C. A.
Published: November 2017

We present observations that provide the strongest evidence yet that discrete whistler mode chorus packets cause relativistic electron microbursts. On 20 January 2016 near 1944 UT the low Earth orbiting CubeSat Focused Investigations of Relativistic Electron Bursts: Intensity, Range, and Dynamics (FIREBIRD II) observed energetic microbursts (near L = 5.6 and MLT = 10.5) from its lower limit of 220 keV, to 1 MeV. In the outer radiation belt and magnetically conjugate, Van Allen Probe A observed rising‐tone, lower band chorus waves with durations and cadences similar to the microbursts. No other waves were observed. This is the first time that chorus and microbursts have been simultaneously observed with a separation smaller than a chorus packet. A majority of the microbursts do not have the energy dispersion expected for trapped electrons bouncing between mirror points. This confirms that the electrons are rapidly (nonlinearly) scattered into the loss cone by a coherent interaction with the large amplitude (up to ∼900 pT) chorus. Comparison of observed time‐averaged microburst flux and estimated total electron drift shell content at L = 5.6 indicate that microbursts may represent a significant source of energetic electron loss in the outer radiation belt.
Effect of Seismogenic Depth and Background Stress on Physical Limits of Earthquake Rupture Across Fault Step Overs
Authors: Bai Kangchen , Ampuero Jean‐Paul
Published: November 2017

Earthquakes can rupture geometrically complex fault systems by breaching fault step overs. Quantifying the likelihood of rupture jump across step overs is important to evaluate earthquake hazard and to understand the interactions between dynamic rupture and fault growth processes. Here we investigate the role of seismogenic depth and background stress on physical limits of earthquake rupture across fault step overs. Our computational and theoretical study is focused on the canonical case of two parallel strike‐slip faults with large aspect ratio, uniform prestress and friction properties. We conduct a systematic set of 3‐D dynamic rupture simulations with different seismogenic depth, step over distance, and initial stresses. We find that the maximum step over distanceHcthat a rupture can jump depends on seismogenic depthWand strength excess to stress drop ratioS, commonly used to evaluate probable rupture velocity, as, wheren= 2 whenHc/W< 0.2 (orS> 1.5) andn= 1 otherwise. The critical nucleation size, largely controlled by frictional properties, has a second‐order effect onHc. Rupture on the secondary fault is mainly triggered by the stopping phase emanated from the rupture end on the primary fault. Asymptotic analysis of the peak amplitude of stopping phases sheds light on the mechanical origin of the relations betweenHc,W, andS, and leads to the scaling regime withn= 1 in far field andn= 2 in near field. The results suggest that strike‐slip earthquakes on faults with large seismogenic depth or operating at high shear stresses can jump wider step overs than observed so far in continental interplate earthquakes.
Space‐Time Patterns of Meteorological Drought Events in the European Greater Alpine Region Over the Past 210 Years
Authors: Haslinger K. , Blöschl G.
Published: November 2017

Droughts may have tremendous impacts on humans. However, the space‐time characteristics of droughts are not very well understood, as case studies usually focus on individual drought events. Here we investigate the spatiotemporal drought characteristics of a large sample of events over the past 210 years in the Greater Alpine Region of Central Europe. We use monthly precipitation data, and flag, for each grid point, time steps with precipitation below a 20% percentile. We then propose a new method that detects drought events by connecting the flagged elements to space‐time drought regions. In contrast to the traditional drought indices that are based on a fixed, prescribed time window, this method is able to identify droughts of different durations in an objective way. The data show multidecadal variations of drought frequency, duration, intensity, and severity, but no consistent trends over the 210 year period. The top 5% of events in terms of their severity show a shift in seasonality from winter/spring events in the late nineteenth century toward autumn events during the last decades of the twentieth century. The most severe events center either in the Northwest or in the Southeast of the region analyzed. We found no significant correlations of drought frequency, duration, intensity, and severity with the temperature increases in the past three decades. Dry springs significantly enhance temperatures during summer droughts, suggesting a soil moisture‐temperature feedback.
pH/Ultrasound Dual‐Responsive Gas Generator for Ultrasound Imaging‐Guided Therapeutic Inertial Cavitation and Sonodynamic Therapy
Authors: Feng Qianhua , Zhang Wanxia , Yang Xuemei , Li Yuzhen , Hao Yongwei , Zhang Hongling , Hou Lin , Zhang Zhenzhong
Published: November 2017

Herein, a pH/ultrasound dual‐responsive gas generator is reported, which is based on mesoporous calcium carbonate (MCC) nanoparticles by loading sonosensitizer (hematoporphyrin monomethyl ether (HMME)) and modifying surface hyaluronic acid (HA). After pinpointing tumor regions with prominent targeting efficiency, HMME/MCC‐HA decomposes instantaneously under the cotriggering of tumoral inherent acidic condition and ultrasound (US) irradiation, concurrently accompanying with CO2 generation and HMME release with spatial/temporal resolution. Afterward, the CO2 bubbling and bursting effect under US stimulus results in cavitation‐mediated irreversible cell necrosis, as well as the blood vessel destruction to further occlude the blood supply, providing a “bystander effect.” Meanwhile, reactive oxygen species generated from HMME can target the apoptotic pathways for effective sonodynamic therapy. Thus, the combination of apoptosis/necrosis with multimechanisms consequently results in a remarkable antitumor therapeutic efficacy, simultaneously minimizing the side effects on major organs. Moreover, the echogenic property of CO2 make the nanoplatform as a powerful ultrasound contrast agent to identify cancerous lesions. Based on the above findings, such all‐in‐one drug delivery platform of HMME/MCC‐HA is utilized to provide the US imaging guidance for therapeutic inertial cavitation and sonodynamic therapy simultaneously, which highlights possibilities of advancing cancer theranostics in biomedical fields.
Flexible and Adaptable Light‐Emitting Coatings for Arbitrary Metal Surfaces based on Optical Tamm Mode Coupling
Authors: Jiménez‐Solano Alberto , Galisteo‐López Juan F. , Míguez Hernán
Published: November 2017

This study demonstrates a design that maximizes the power radiated into free space from a monolayer of nanoemitters embedded in a flexible distributed Bragg reflector conformably attached to a metal surface. This is achieved by positioning the light source at the precise depth within the multilayer for which optical Tamm states provide enhanced quantum yield and outcoupling efficiency, which are combined to optimize the luminous power radiated by the surface of the ensemble. This approach, based on the adhesion of flexible multilayer stacks onto metal surfaces with an arbitrary curvature, is versatile and permits the realization of spectrally narrow monodirectional or self‐focusing light‐emitting surfaces.
Cyclopropanation of Benzene Rings by Oxidatively Generated α‐Oxo Gold Carbene: One‐Pot Access to Tetrahydropyranone‐Fused Cycloheptatrienes from Propargyl Benzyl Ethers
Authors: Ji Kegong , Zhang Liming
Published: November 2017

Cyclopropanations of benzene rings by oxidatively generated α‐oxo gold carbenes are for the first time demonstrated in a Buchner reaction, in which readily available propargyl benzyl ethers are converted in one‐pot to tetrahydropyranone‐fused cycloheptatrienes via sequential oxidative gold catalysis and base‐promoted isomerization. Additional examples of arene cyclopropanations without fragmentation of the cyclopropane ring are also realized.

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Fabrication of Solvent‐Resistant Copolyimide Membranes for Pervaporation Recovery of Amide Solvents
Authors: Xu Rong , Guo Meng , Wang Jin , Zhang Qi , Zhong Jing
Published: November 2017

Dimethylformamide and dimethylacetamide are important industrial chemicals, which are used, e.g., as solvents in the manufacturing of polyurethane products. They are conventionally recovered by distillation associated with high energy consumption and operating costs. In contrast, pervaporation is an energy‐efficient membrane separation method. Ceramic‐supported copolyimide membranes were synthesized via the two‐step thermal imidization method and applied to pervaporation recovery of dimethylformamide and dimethylacetamide. The prepared membrane demonstrated high resistance to the two amides in a wide concentration range. Effects of operating parameters such as feed temperature and feed concentration on pervaporation performances were investigated. The results showed that the copolyimide membrane is a promising candidate for the recovery of high concentrations of amide solvents.
Axial Backmixing and Residence Time Distribution in a Miniaturized, Stirred‐Pulsed Extraction Column
Authors: Soboll Sebastian , Bittorf Lukas , Kockmann Norbert
Published: November 2017

Axial backmixing is an important issue in extraction columns since it heavily affects the mass transfer performance. A miniaturized, stirred‐pulsed column was investigated regarding its backmixing characteristics in the continuous phase, using the system water/n‐butyl acetate. Residence time distributions were determined through pulse experiments with potassium chloride, which was detected via electrical conductivity. To perform the conductivity measurement without distortion of the two‐phase flow, electrodes with an annular design that precisely line up with the inner column wall were manufactured. This design is a promising alternative for use in small‐scale tubular devices where commercial electrodes do not fit and in applications where interference with the flow must be avoided.
Mesenchymal Stem Cell Preparation and Transfection‐free Ferumoxytol Labeling for MRI Cell Tracking
Authors: Liu Li , Ho Chien
Published: November 2017

Mesenchymal stem cells (MSCs) are multipotent cells and are the most widely studied cell type for stem cell therapies. In vivo cell tracking of MSCs labeled with an FDA‐approved superparamagnetic iron‐oxide (SPIO) particle by magnetic resonance imaging (MRI) provides essential information, e.g., MSC engraftment, survival, and fate, thus improving cell therapy accuracy. However, current methodology for labeling MSCs with Ferumoxytol (Feraheme®), the only FDA‐approved SPIO particle, needs transfection agents. This unit describes a new “bio‐mimicry” protocol to prepare more native MSCs by using more “in vivo environment” of MSCs, so that the phagocytic activity of cultured MSCs is restored and expanded MSCs can be labeled with Ferumoxytol, without the need for transfection agents and/or electroporation. Moreover, MSCs re‐size to a more native size, reducing from 32.0 to 19.5 μm. The MSCs prepared from this protocol retain more native properties and would be useful for biomedical applications and MSC‐tracking studies by MRI. © 2017 by John Wiley & Sons, Inc.
Human Adipose‐Derived Stromal Cell Isolation Methods and Use in Osteogenic and Adipogenic In Vivo Applications
Authors: Brett Elizabeth , Tevlin Ruth , McArdle Adrian , Seo Eun Young , Chan Charles K.F. , Wan Derrick C. , Longaker Michael T.
Published: November 2017

Adipose tissue represents an abundant and easily accessible source of multipotent cells, which may serve as excellent building blocks for tissue engineering. This article presents a newly described protocol for isolating adipose‐derived stromal cells (ASCs) from human lipoaspirate, compared to the standard protocol for harvesting ASCs established in 2001.

Human ASC isolation is performed using two methods, and resultant cells are compared through cell yield, cell viability, cell proliferation and regenerative potential. The osteogenic and adipogenic potential of ASCs isolated using both protocols are assessed in vitro and gene expression analysis is performed. The focus of this series of protocols is the regenerative potential of both cell populations in vivo. As such, the two in vivo animal models described are fat graft retention (soft tissue reconstruction) and calvarial defect healing (bone regeneration). The techniques described comprise fat grafting with cell assisted lipotransfer, and calvarial defect creation healed with cell‐seeded scaffolds. © 2017 by John Wiley & Sons, Inc.
Potential contributions of root decomposition to the nitrogen cycle in arctic forest and tundra
Authors: Träger Sabrina , Milbau Ann , Wilson Scott D.
Published: November 2017

Plant contributions to the nitrogen (N) cycle from decomposition are likely to be altered by vegetation shifts associated with climate change. Roots account for the majority of soil organic matter input from vegetation, but little is known about differences between vegetation types in their root contributions to nutrient cycling. Here, we examine the potential contribution of fine roots to the N cycle in forest and tundra to gain insight into belowground consequences of the widely observed increase in woody vegetation that accompanies climate change in the Arctic. We combined measurements of root production from minirhizotron images with tissue analysis of roots from differing root diameter and color classes to obtain potential N input following decomposition. In addition, we tested for changes in N concentration of roots during early stages of decomposition, and investigated whether vegetation type (forest or tundra) affected changes in tissue N concentration during decomposition. For completeness, we also present respective measurements of leaves. The potential N input from roots was twofold greater in forest than in tundra, mainly due to greater root production in forest. Potential N input varied with root diameter and color, but this variation tended to be similar in forest and tundra. As for roots, the potential N input from leaves was significantly greater in forest than in tundra. Vegetation type had no effect on changes in root or leaf N concentration after 1 year of decomposition. Our results suggest that shifts in vegetation that accompany climate change in the Arctic will likely increase plant‐associated potential N input both belowground and aboveground. In contrast, shifts in vegetation might not alter changes in tissue N concentration during early stages of decomposition. Overall, differences between forest and tundra in potential contribution of decomposing roots to the N cycle reinforce differences between habitats that occur for leaves.
Reengineered Coal‐Fired Power Plants Competitive With Gas Turbine Plants
Authors: Moore Keith , Giberson Melbourne F.
Published: November 2017

In just the past few years, some 572 US coal‐fired power plants (and some nuclear plants) have been—or are scheduled to be—mothballed, shut down, or abandoned, and along with their loss comes the loss of many thousands of jobs that support the electric‐generating industry.
How do emerging multinationals configure political connections across institutional contexts?
Authors: Chen Liang , Li Yi , Fan Di
Published: November 2017

Research Summary

Forming informal ties with political agents is viewed as a viable strategy for multinational enterprises seeking to enter emerging countries. Less is known about the conditions under which political connection is most helpful for firms dealing with cross‐border institutional distance. We discuss the distinctive mechanisms through which emerging multinationals may benefit from both home and host political connections. Based on the strategy tripod perspective, we postulate that the importance of different types of connections depends on the overall configurations of a firm’s resources and industry characteristics, and these may change with institutional distance. Our analysis of a sample of Chinese high‐tech manufacturing firms yields new insights into political connections, institutional distance, and the strategy tripod perspective.

Managerial Summary

Political connections play an important role in firms’ international expansion. In this study, we consider the importance of home political connections and host political connections in overcoming institutional barriers to foreign entry. We show that this importance varies, depending on firms’ resource bases and industry dynamics, and it may switch from a useful asset to a dispensable one under certain circumstances. We reach our conclusion from an analysis of Chinese high‐tech manufacturing firms’ foreign direct investment.
Long noncoding RNA H19 interacts with polypyrimidine tract‐binding protein 1 to reprogram hepatic lipid homeostasis
Authors: Liu Chune , Yang Zhihong , Wu Jianguo , Zhang Li , Lee Sangmin , Shin Dong‐Ju , Tran Melanie , Wang Li
Published: November 2017

H19 is an imprinted long noncoding RNA abundantly expressed in embryonic liver and repressed after birth. We show that H19 serves as a lipid sensor by synergizing with the RNA‐binding polypyrimidine tract‐binding protein 1 (PTBP1) to modulate hepatic metabolic homeostasis. H19 RNA interacts with PTBP1 to facilitate its association with sterol regulatory element‐binding protein 1c mRNA and protein, leading to increased stability and nuclear transcriptional activity. H19 and PTBP1 are up‐regulated by fatty acids in hepatocytes and in diet‐induced fatty liver, which further augments lipid accumulation. Ectopic expression of H19 induces steatosis and pushes the liver into a “pseudo‐fed” state in response to fasting by promoting sterol regulatory element‐binding protein 1c protein cleavage and nuclear translocation. Deletion of H19 or knockdown of PTBP1 abolishes high‐fat and high‐sucrose diet–induced steatosis. Conclusion: Our study unveils an H19/PTBP1/sterol regulatory element‐binding protein 1 feedforward amplifying signaling pathway to exacerbate the development of fatty liver. (Hepatology 2018;67:1768‐1783)
TIMAP, the versatile protein phosphatase 1 regulator in endothelial cells
Authors: Boratkó Anita , Csortos Csilla
Published: November 2017

Transforming growth factor (TGF)‐β inhibited membrane associated protein, TIMAP, is the member of the myosin phosphatase targeting protein (MYPT) family of protein phosphatase 1 (PP1) regulatory subunits. The N‐terminal part of TIMAP has a typical MYPT family structure with a sequence element called MyPhone (myosin phosphatase N‐terminal element), a putative bipartite nuclear localization signal, a PP1 catalytic subunit binding motif, and five ankyrin repeats. The C‐terminal half of TIMAP is intrinsically disordered, but ends with a functional CAAX box for lipid modification which allows localization of TIMAP at the plasma membrane. TIMAP is prenylated by farnesyl transferase with the contribution of the anchoring protein, RACK1 in the cytoplasm. The controlling effect of TIMAP on PP1 is moderated by PKA/GSK3β and PKC mediated phosphorylation of TIMAP, the sites are located in the disordered region of the protein. TIMAP is abundant in endothelial cells. A growing body of evidence attained through characterization of newly identified protein partners calls attention to its critical role in normal and pathological activities of the endothelium via regulation of PP1. TIMAP binds the non‐integrin laminin receptor 1 and the endothelin converting enzyme 1, which may connect TIMAP to angiogenesis, tumor invasion and metastasis. Barrier protecting role of TIMAP was shown for pulmonary artery endothelial cells. ERM (ezrin‐radixin‐moesin) proteins, as potential in vivo PP1‐TIMAP substrates, are critical targets in the barrier maintenance. TIMAP affects phosphorylation level and subcellular localization of merlin and eukaryotic elongation factor‐1A1. Merlin is a key component of signaling pathways regulating cell proliferation, membrane domain formation and cell‐cell junction organization. Noncanonical functions of the elongation factor include a role in organization of cytoskeleton dynamics and in apoptosis. The interacting/binding partners identified so far demonstrate a rather complex role of TIMAP in key functions of the endothelium offering TIMAP as a plausible target in pathological issues. © 2017 IUBMB Life, 69(12):918–928, 2017
Study of the protective effect of ischemic and pharmacological preconditioning on hepatic ischemic reperfusion injury induced in rats
Authors: Osman Afaf S , Osman Ahmed H , Kamel Mahmoud M
Published: November 2017

Background and Aim

Hepatic ischemia reperfusion injury is the main cause of liver failure following liver surgery, so an effective method is needed to prevent or reduce this hepatic injury. The aim of the present study is to investigate the potential effect of ischemic preconditioning versus pharmacological preconditioning with lisinopril or verapamil for protection against hepatic ischemia reperfusion injury induced in rats.

Methods

Rats were divided into six groups. Group I served as control untreated. Rats of group II were subjected to laparotomy without induction of ischemia reperfusion. Ischemia reperfusion by ligation of the portal trait for 30 min, followed by reperfusion for 2 h, was performed in rats of groups III–VI. Ischemic preconditioning was performed for rats of group IV before induction of ischemia reperfusion. Lisinopril and verapamil was given daily for 3 days before induction of ischemia reperfusion in groups V and VI, respectively. Serum level of liver transaminases and liver malondialdehyde content were measured, and hepatic histopathological examination was assessed.

Results

Induction of ischemia reperfusion resulted in significant elevation of liver transaminases and liver malondialdehyde content associated with significant hepatic histopathological injury that were significantly improved by ischemic preconditioning, lisinopril, or verapamil treatment. Verapamil showed the most significant improvement compared with ischemic preconditioning or lisinopril treatment.

Conclusion

Ischemic preconditioning and pharmacological preconditioning by lisinopril or verapamil can protect against hepatic ischemia reperfusion probably through inhibition of oxidative stress and neutrophil infiltration. The most potent protection is demonstrated by verapamil treatment.