bluuebunny/crossref_metadata_2025_split huggingface dataset:
A basal stress parameterization for modeling landfast ice
Authors: Lemieux Jean‐François , Tremblay L. Bruno , Dupont Frédéric , Plante Mathieu , Smith Gregory C. , Dumont Dany 
Published: April 2015

AbstractCurrent large‐scale sea ice models represent very crudely or are unable to simulate the formation, maintenance and decay of coastal landfast ice. We present a simple landfast ice parameterization representing the effect of grounded ice keels. This parameterization is based on bathymetry data and the mean ice thickness in a grid cell. It is easy to implement and can be used for two‐thickness and multithickness category models. Two free parameters are used to determine the critical thickness required for large ice keels to reach the bottom and to calculate the basal stress associated with the weight of the ridge above hydrostatic balance. A sensitivity study was conducted and demonstrates that the parameter associated with the critical thickness has the largest influence on the simulated landfast ice area. A 6 year (2001–2007) simulation with a 20 km resolution sea ice model was performed. The simulated landfast ice areas for regions off the coast of Siberia and for the Beaufort Sea were calculated and compared with data from the National Ice Center. With optimal parameters, the basal stress parameterization leads to a slightly shorter landfast ice season but overall provides a realistic seasonal cycle of the landfast ice area in the East Siberian, Laptev and Beaufort Seas. However, in the Kara Sea, where ice arches between islands are key to the stability of the landfast ice, the parameterization consistently leads to an underestimation of the landfast area.
Biodegradation of subsurface oil in a tidally influenced sand beach: Impact of hydraulics and interaction with pore water chemistry
Authors: Geng Xiaolong , Boufadel Michel C. , Lee Kenneth , Abrams Stewart , Suidan Makram 
Published: April 2015

AbstractThe aerobic biodegradation of oil in tidally influenced beaches was investigated numerically in this work using realistic beach and tide conditions. A numerical model BIOMARUN, coupling a multiple‐Monod kinetic model BIOB to a density‐dependent variably saturated groundwater flow model 2‐D MARUN, was used to simulate the biodegradation of low‐solubility hydrocarbon and transport processes of associated solute species (i.e., oxygen and nitrogen) in a tidally influenced beach environment. It was found that different limiting factors affect different portions of the beach. In the upper intertidal zone, where the inland incoming nutrient concentration was large (1.2 mg N/L), oil biodegradation occurred deeper in the beach (i.e., 0.3 m below the surface). In the midintertidal zone, a reversal was noted where the biodegradation was fast at shallow locations (i.e., 0.1 m below the surface), and it was due to the decrease of oxygen with depth due to consumption, which made oxygen the limiting factor for biodegradation. Oxygen concentration in the midintertidal zone exhibited two peaks as a function of time. One peak was associated with the high tide, when dissolved oxygen laden seawater filled the beach and a second oxygen peak was observed during low tides, and it was due to pore oxygen replenishment from the atmosphere. The effect of the capillary fringe (CF) height was investigated, and it was found that there is an optimal CF for the maximum biodegradation of oil in the beach. Too large a CF (i.e., very fine material) would attenuate oxygen replenishment (either from seawater or the atmosphere), while too small a CF (i.e., very coarse material) would reduce the interaction between microorganisms and oil in the upper intertidal zone due to rapid reduction in the soil moisture at low tide.
Einfluss der Wärmespeicherfähigkeit auf die energetische Flexibilität von Gebäuden
Authors: Hall Monika , Geissler Achim 
Published: April 2015

AbstractÜblicherweise speisen Gebäude mit Photovoltaikanlagen einen Großteil des Ertrags in das öffentliche Stromnetz ein. Um den Eigenverbrauch zu erhöhen, bietet es sich bei gut gedämmten Gebäuden an, die Laufzeit der Wärmepumpe auf die Tageszeit zu limitieren. Dabei muss der thermische Komfort gewährleistet bleiben. In diesem Zusammenhang wird der Einfluss der Wärmespeicherfähigkeit des Gebäudes auf die operativen Temperaturen in Abhängigkeit von verschiedenen Laufzeiten der Wärmepumpe mit einer thermischen Gebäudesimulation untersucht und mit Messwerten von einem kleinen Mehrfamilienhaus validiert.Es wird gezeigt, dass auch bei einem sehr gut gedämmten Gebäude eine mittlere bis hohe Wärmespeicherfähigkeit vorhanden sein muss, damit die Laufzeit der Wärmepumpe ohne Komforteinbuße auf die Tagesstunden limitiert werden kann. Mit einem Leichtbau ist die gewählte Strategie nicht möglich. Die lange tägliche Sperrzeit bedingt, dass gegenüber dem kontinuierlichen Betrieb die operative Temperatur größeren Schwankungen unterworfen ist. Das Niveau und die Breite des zulässigen Temperaturbandes müssen mit den normativen Anforderungen für die Behaglichkeit abgestimmt sein. Die Diskussion über normative Behaglichkeitsanforderungen versus energetische Flexibilität des Gebäudes muss lanciert werden.Influence of thermal mass on the energy flexibility of buildings. Usually Buildings with photovoltaic systems feed a large amount of electricity into the public grid. Shifting duty cycles of the heat pump into the daytime would therefore be a possible means to greatly increase the self‐consumption of a well isolated building. However, thermal comfort should not deteriorate. The impact of the thermal capacity of the construction and the limitations of reducing heat pump run‐times on operative temperatures are investigated by transient thermal building simulation. The simulation is validated with monitored data from a small residential building.The results obtained show that a well insulated building must have a middle or high thermal capacity to be able to limit the run‐time of the heat pump to daytime without incurring a non‐negligible loss of thermal comfort. The run‐time limitation proves to not be possible with a lightweight construction (low thermal capacity). Due to the long daily intervals without heat input, the fluctuation of the operative temperature is higher than with continuous heat pump operation. The level and fluctuation width of the operative temperatures should be in accordance with requirements from comfort standards. Results from the work described herein clearly show that a discussion about requirements in comfort standards versus energy flexibility of buildings must be initiated.
Proximity Effect on the Induced Geoelectric Field at the Lateral Interface of Different Conductivity Structures During Geomagnetic Storms
Authors: Bo DONG , Ze‐Zhong WANG , Lian‐Guang LIU , Li‐Ping LIU , Chun‐Ming LIU 
Published: April 2015

AbstractThe induced geoelectric fields and telluric currents generated during geomagnetic storms will be distorted by lateral variations of the Earth conductivity. The Galerkin finite element method (FEM) is a useful tool to analyze complicated electromagnetic field problems. In this paper, a uniform thin sheet current with infinite width located at 100 km above the Earth's surface is assumed to represent the source of geomagnetic variations. It is harmonic with the amplitude of 1 A/m at different frequencies. Three Earth conductivity structures are modelled where the basic model is horizontally uniform for comparisons. The second and third structures have the same exact thicknesses and conductivity values with the basic one on one side and five times greater or lower values on the other side to represent conductivity variation from low to high and from high to low. The computational results show that the abrupt changes of conductivities have influences on the induced telluric currents, which can be classified as the proximity effect and the skin effect. For GIC research in power systems, especially in systems located at coastal areas, the geoelectric field and GIC should be determined taking the directions of the transmission lines and of the coast into consideration. Both the proximity effect and the skin effect should be considered along with the coast effect in research of GIC impacts during geomagnetic disturbances. Boundary conditions discussed in this paper can be varied depending on different modelling techniques and on the scales of conductivity structure models.
A Multi‐Scale Scratch Analysis Method for Quantitative Interpretation of Regional Gravity Fields
Authors: Wen‐Cai YANG , Yan‐Yun SUN , Zun‐Ze HOU , Chang‐Qing YU 
Published: April 2015

AbstractThis paper presents new systematic methods of regional gravity data processing that combine theories based on multi‐scale wavelet analysis, spectral analysis of potential fields, geophysical inversion, and information extraction. We call this data processing system as the multi‐scale scratch analysis for delineation of crustal structures, deformation belts and division of continental tectonic units. The multi‐scale scratch analysis contains four modules; they are spectral analysis for division of density layers, decomposition of the field by using wavelet transformation and multi‐scale analysis, depth estimation and density inversion of decomposed gravity anomalies, and scratch analysis. The basic principles, application techniques and examples for each module are explained. As a complicated and sophisticated process, the multi‐discipline research on regional geophysics from geophysical investigation to tectonic results requires combination of new methods and techniques coming from different disciplines, to build a wide and thick theoretic base for supporting the multi‐discipline research. The multi‐scale scratch analysis combines supporting bases coming from applied mathematics, geophysics, and information science respectively.
Terrain Evolution of China Seas and Land Since the Indo‐China Movement and Characteristics of the Stepped Landform
Authors: Xun‐Hua ZHANG , Zhong‐Lei WANG , Fang‐Hui HOU , Jin‐Yu YANG , Xing‐Wei GUO 
Published: April 2015

AbstractTerrain is the situation of the ground rising and falling, which is controlled by both the endogenetic and exogenic forces of the earth. The terrain reflects the internal structure, construction, and evolution of the curst. Free‐air gravity anomalies are related to topography and geomorphology. It is considered that the curst that under mountains is thicker than that under plains by the equalization principle. There is a mirror image relationship between crust thickness and terrain relief. The map series of geology and geophysics of China seas and land include figures of tectonic framework and evolution of tectonic framework. The temporal evolution of the main blocks is studied in both of the maps, which elaborate the evolution of China's terrain as a “Seesaw”. This paper analyzes the geomorphological features by the free‐air gravity anomaly map and Moho depth distribution map. In accordance with the principle of tectonic landform classification, the general characteristics of China seas and land is viewed as a whole which shows five terrain steps from west to east on the basis of three geomorphological ladders of Chinese land.
A New Understanding on the Pattern of Deep Faults in Xizang and the Southwestern Sanjiang Area
Authors: Sheng‐Qing XIONG , Yan‐Yun DING , Zhan‐Kui LI 
Published: April 2015

AbstractExtremely complicated fault structures characterize Xizang and the Sanjiang (Jinsha River, Lancang River, Nujiang River) region in southwest China. In spite of many years' study, different recognitions to this issue remain present. Based on new aeromagnetic data and gravity data, and from the view of combining gravity and magnetic characteristics with geological structure, we compile a new map of fault structures in Xizang and the southwestern Sanjiang region. The results show that the deep faults along the Jinsha River, Lancang River and Nujiang River are independent NW‐striking faults which extend from the south to the northwest, not connecting with the arc‐like faults in Xizang which extend from the east to the west. These faults are newly discovered NW‐striking faults in the Tethys fault system and belong to a different fault system relative to EW‐striking faults in Xizang. This opinion is different from the previous view that the suture zones of Jinsha River, Lungmu Co‐Lancang River and Bangong Co‐Nujiang River extend towards NW and EW in arc distribution. This discovery of the faults has changed the recognition of fault structure framework of Xizang‐Sanjiang areas, which lends light on the geotectonic research in the future. In this paper, the west extending characteristics of deep fault belt developed in Xizang and southwest Sanjiang River area are mainly explained, and the intersection relationship of faults between the Sanjiang River and Xizang is also discussed, which indicates that gravity and magnetic data are significant for the research on fault structures.
Mitochondrially‐Imported RNA in Drug Discovery
Authors: Cannon Matthew V. , Irwin Michael H. , Pinkert Carl A. 
Published: April 2015

ABSTRACT

Preclinical Research

The import of nuclear transcribed RNAs into mitochondria is an emerging area that presents a tremendous opportunity to develop human metabolic therapeutics. However, our knowledge base is quite limited. Much remains to be discovered regarding specific RNA localization and mechanisms of import. To identify novel RNAs imported into mitochondria, all RNAs within the mitochondria were characterized using next generation sequencing technology. Several nuclear transcribed RNAs were found within mitochondrial RNA (mtRNA) samples, including nuclear ribosomal RNAs, gamma satellite RNA and VL30 retroelement RNA. The presence of these RNAs within mitochondria coupled with RNA sequencing data from other laboratories investigating mtRNA processing, lead us to hypothesize that nuclease treatment of mitoplasts is insufficient for removing contaminating cytoplasmic RNAs. In contrast to traditional methodology, mitochondrial import was evaluated by qRT‐PCR after stepwise removal of the outer mitochondrial membrane and subsequent lysis of mitochondria. This allowed identification of RNAs lost from the mitochondria with the same kinetics as mitochondrial DNA‐transcribed RNAs. This approach provided an improved evaluation of nuclear RNA enrichment within mitochondrial membranes to characterize nuclease protection and mitochondrial import and identify false‐positive detection errors. qRT‐PCR results confirmed the presence of VL30 retroelement RNA within mitochondria and question the hypothesis that the RNA component of RNase P is imported. These results illustrate a reliable approach for evaluating the presence of RNAs within mitochondria and open new avenues of investigation relating to mtRNA biology and in targeting mitochondrial based therapeutics. Drug Dev Res 76 : 8261–71, 2015. © 2015 Wiley Periodicals, Inc.
Antioxidant‐Mediated Reversal of Oxidative Damage in Mouse Modeling of Complex I Inhibition
Authors: Parameshwaran Kodeeswaran , Irwin Michael H. , Steliou Kosta , Suppiramaniam Vishnu , Pinkert Carl A. 
Published: April 2015

ABSTRACT

Preclinical Research

Mitochondrial dysfunction is a key component of various aging‐related pathologies of the brain that result in dementia. As such, it provides an important avenue in development of therapeutic interventions for a host of neurological disorders. A requirement for functional mitochondrial respiratory chain complex I (CI), to accomplish the normal physiological processes regulating memory, seems intuitive. In the present study, a synthetic lipoylcarnitine antioxidant (PMX‐500FI; 100 mg/kg/day po) was administered to female ICR mice (3–4‐month old) that were subsequently treated with the mitochondrial CI inhibitor, rotenone (400 mg/kg/day). After 1 week, rotenone‐induced impairment of neuronal function was evaluated in the hippocampus, a brain region that is involved in regulating memory formation. Electrophysiological recordings in live brain slices showed that long‐term potentiation (LTP) was reduced by rotenone exposure (P < 0.05) while pretreatment with PMX‐500FI maintained LTP similar to control levels (P > 0.05). Potentiation during theta burst stimulation (TBS) was similar among treatment groups (P > 0.05); however, neurotransmitter release, which increased in control mice after TBS, was lower in rotenone treated mice (P < 0.05), and was accompanied by reduced basal synaptic transmission (P < 0.05), increased proapoptotic signaling and decreased extracellular signal‐regulated kinase1/2 (ERK1/2) phosphorylation (P < 0.05). For each of these determinations, pretreatment with PMX‐500FI alleviated the harmful effects of rotenone. These results illustrate that treatment with antioxidant PMX‐500FI is protective against rotenone‐induced impairment of neuronal bioenergetics in the mouse hippocampus, in regard to both excitatory synaptic physiology and proapoptotic signaling. The protective effect of PMX‐500FI against rotenone‐induced disruption of cellular bioenergetics may have important therapeutic implications for treating aging‐related dementia and other diseases related to mitochondrial dysfunction and/or oxidative damage. Drug Dev Res 76 : 8272–81, 2015. © 2015 Wiley Periodicals, Inc.
Phosphate and Thiophosphate Biphenyl Analogs as Steroid Sulfatase Inhibitors
Authors: Demkowicz Sebastian , Kozak Witold , Daśko Mateusz , Masłyk Maciej , Kubiński Konrad , Rachon Janusz 
Published: April 2015

ABSTRACT

Preclinical Research

In the present work, we report convenient methods for the synthesis and biological evaluation of phosphate and thiophosphate biphenyl derivatives exhibiting steroid sulfatase (STS) activity. The described synthesis is based on straightforward preparation of biphenyl‐4‐ol and 4′‐hydroxy‐biphenyl‐4‐carboxylic acid ethyl ester modified with various phosphate or thiophosphate moieties. The inhibitory effects of these compounds were tested on STS isolated from human placenta and led to two compounds of interest, 5a and 5d with IC50 values of 28.0 and 22.1 µM, respectively and that had interesting new binding modes in the STS active site. Drug Dev Res 76 : 8294–104, 2015. © 2015 Wiley Periodicals, Inc.
Contractile activity is required for Z‐disc sarcomere maturation in vivo
Authors: Geach Timothy J. , Hirst Elizabeth M.A. , Zimmerman Lyle B. 
Published: April 2015

SummarySarcomere structure underpins structural integrity, signaling, and force transmission in the muscle. In embryos of the frog Xenopus tropicalis, muscle contraction begins even while sarcomerogenesis is ongoing. To determine whether contractile activity plays a role in sarcomere formation in vivo, chemical tools were used to block acto‐myosin contraction in embryos of the frog X. tropicalis, and Z‐disc assembly was characterized in the paralyzed dicky ticker mutant. Confocal and ultrastructure analysis of paralyzed embryos showed delayed Z‐disc formation and defects in thick filament organization. These results suggest a previously undescribed role for contractility in sarcomere maturation in vivo. genesis 53:299–307, 2015. © 2015 The Authors. Genesis Published by Wiley Periodicals, Inc.
Disulfiram/copper‐disulfiram Damages Multiple Protein Degradation and Turnover Pathways and Cytotoxicity is Enhanced by Metformin in Oesophageal Squamous Cell Carcinoma Cell Lines
Authors: Jivan Rupal , Damelin Leonard Howard , Birkhead Monica , Rousseau Amanda Louise , Veale Robin Bruce , Mavri‐Damelin Demetra 
Published: April 2015

ABSTRACTDisulfiram (DSF), used since the 1950s in the treatment of alcoholism, is reductively activated to diethyldithiocarbamate and both compounds are thiol‐reactive and readily complex copper. More recently DSF and copper‐DSF (Cu‐DSF) have been found to exhibit potent anticancer activity. We have previously shown that the anti‐diabetic drug metformin is anti‐proliferative and induces an intracellular reducing environment in oesophageal squamous cell carcinoma (OSCC) cell lines. Based on these observations, we investigated the effects of Cu‐DSF and DSF, with and without metformin, in this present study. We found that Cu‐DSF and DSF caused considerable cytotoxicity across a panel of OSCC cells, and metformin significantly enhanced the effects of DSF. Elevated copper transport contributes to DSF and metformin‐DSF‐induced cytotoxicity since the cell‐impermeable copper chelator, bathocuproinedisulfonic acid, partially reversed the cytotoxic effects of these drugs, and interestingly, metformin‐treated OSCC cells contained higher intracellular copper levels. Furthermore, DSF may target cancer cells preferentially due to their high dependence on protein degradation/turnover pathways, and we found that metformin further enhances the role of DSF as a proteasome inhibitor. We hypothesized that the lysosome could be an additional, novel, target of DSF. Indeed, this acid‐labile compound decreased lysosomal acidification, and DSF‐metformin co‐treatment interfered with the progression of autophagy in these cells. In summary, this is the first such report identifying the lysosome as a target of DSF and based on the considerable cytotoxic effects of DSF either alone or in the presence of metformin, in vitro, and we propose these as novel potential chemotherapeutic approaches for OSCC. J. Cell. Biochem. 116: 2334–2343, 2015. © 2015 Wiley Periodicals, Inc.
Accuracy of multiecho magnitude‐based MRI (M‐MRI) for estimation of hepatic proton density fat fraction (PDFF) in children
Authors: Zand Kevin A. , Shah Amol , Heba Elhamy , Wolfson Tanya , Hamilton Gavin , Lam Jessica , Chen Joshua , Hooker Jonathan C. , Gamst Anthony C. , Middleton Michael S. , Schwimmer Jeffrey B. , Sirlin Claude B. 
Published: April 2015

PurposeTo assess accuracy of magnitude‐based magnetic resonance imaging (M‐MRI) in children to estimate hepatic proton density fat fraction (PDFF) using two to six echoes, with magnetic resonance spectroscopy (MRS) ‐measured PDFF as a reference standard.MethodsThis was an IRB‐approved, HIPAA‐compliant, single‐center, cross‐sectional, retrospective analysis of data collected prospectively between 2008 and 2013 in children with known or suspected nonalcoholic fatty liver disease (NAFLD). Two hundred eighty‐six children (8–20 [mean 14.2 ± 2.5] years; 182 boys) underwent same‐day MRS and M‐MRI. Unenhanced two‐dimensional axial spoiled gradient‐recalled‐echo images at six echo times were obtained at 3T after a single low‐flip‐angle (10°) excitation with ≥ 120‐ms recovery time. Hepatic PDFF was estimated using the first two, three, four, five, and all six echoes. For each number of echoes, accuracy of M‐MRI to estimate PDFF was assessed by linear regression with MRS‐PDFF as reference standard. Accuracy metrics were regression intercept, slope, average bias, and R2.ResultsMRS‐PDFF ranged from 0.2–40.4% (mean 13.1 ± 9.8%). Using three to six echoes, regression intercept, slope, and average bias were 0.46–0.96%, 0.99–1.01, and 0.57–0.89%, respectively. Using two echoes, these values were 2.98%, 0.97, and 2.72%, respectively. R2 ranged 0.98–0.99 for all methods.ConclusionUsing three to six echoes, M‐MRI has high accuracy for hepatic PDFF estimation in children. J. Magn. Reson. Imaging 2015;42:1223–1232.