bluuebunny/crossref_metadata_2025 huggingface dataset:
Surface mixed layer deepening through wind shear alignment in a seasonally stratified shallow sea
Authors: Lincoln B. J. , Rippeth T. P. , Simpson J. H.
Published: July 2016

Inertial oscillations are a ubiquitous feature of the surface ocean. Here we combine new observations with a numerical model to investigate the role of inertial oscillations in driving deepening of the surface mixed layer in a seasonally stratified sea. Observations of temperature and current structure, from a mooring in the Western Irish Sea, reveal episodes of strong currents (>0.3 m s−1) lasting several days, resulting in enhanced shear across the thermocline. While the episodes of strong currents are coincident with windy periods, the variance in the shear is not directly related to the wind stress. The shear varies on a subinertial time scale with the formation of shear maxima lasting several hours occurring at the local inertial period of 14.85 h. These shear maxima coincide with the orientation of the surface current being at an angle of approximately 90° to the right of the wind direction. Observations of the water column structure during windy periods reveal deepening of the surface mixed layer in a series of steps which coincide with a period of enhanced shear. During the periods of enhanced shear gradient, Richardson number estimates indicate Ri−1 ≥ 4 at the base of the surface mixed layer, implying the deepening as a result of shear instability. A one‐dimensional vertical exchange model successfully reproduces the magnitude and phase of the shear spikes as well as the step‐like deepening. The observations and model results therefore identify the role of wind shear alignment as a key entrainment mechanism driving surface mixed layer deepening in a shallow, seasonally stratified sea.
The QBO, gravity waves forced by tropical convection, and ENSO
Authors: Geller Marvin A. , Zhou Tiehan , Yuan Wei
Published: July 2016

By means of theory, a simplified cartoon illustrating wave forcing of the stratospheric quasi‐biennial oscillation (QBO), and general circulation modeling of the QBO, it is argued that the period of the QBO is mainly controlled by the magnitude of the gravity wave (GW) vertical fluxes of horizontal momentum (GWMF) forcing the QBO, while the QBO amplitude is mainly determined by the phase speeds of the GWs that make up this momentum flux. It is furthermore argued that it is the zonally averaged GWMF that principally determines the QBO period irrespective of the longitudinal distribution of this GW momentum flux. These concepts are used to develop a hypothesis for the cause of a previously reported El Niño–Southern Oscillation (ENSO) modulation of QBO periods and amplitudes. Some observational evidence is reported for the ENSO modulation of QBO amplitudes to have been different before the 1980s than after about 1990. A hypothesis is also given to explain this in terms of the different ENSO modulation of tropical deep convection that took place before the 1980s from that which occurred after about 1990. The observational evidence, while consistent with our hypotheses, does not prove that our hypotheses are correct given the small number of El Niños and La Niñas that occurred in the early and later periods. Further research is needed to support or refute our hypotheses.
Exploring HF‐induced ionospheric turbulence by Doppler sounding and stimulated electromagnetic emissions at the High Frequency Active Auroral Research Program heating facility
Authors: Sergeev Evgeny N. , Shindin Alexey V. , Grach Savely M. , Milikh Gennady M. , Mishin Evgeny V. , Bernhardt Paul A. , Siefring Carl L. , Briczinski Stanley J. , McCarrick Michael J.
Published: July 2016

We report on the features of the F region plasma perturbations during HF heating experiments at the High Frequency Active Auroral Research Program facility in March–April 2011 and May–June 2014. The diagnostics included multifrequency Doppler (phase) sounding (MDS) and stimulated electromagnetic emission (SEE). The results concern modification of the electron density profile near the reflection and upper hybrid heights, as well as correlation of the density modification with temporal behavior of narrow continuum, downshifted maximum, and broad continuum SEE spectral features. We reveal also a new SEE spectral feature which appears in the SEE spectra for the pump frequency f0 near the third and fourth electron gyroharmonics. It is located in the SEE spectrum well below the pump wave frequency, f − f0 ~ −(40–220) kHz, occupies a wide frequency range till 100–150 kHz, and is termed the broad downshifted emission.
Statistical properties of the radiation belt seed population
Authors: Boyd A. J. , Spence H. E. , Huang C.‐L. , Reeves G. D. , Baker D. N. , Turner D. L. , Claudepierre S. G. , Fennell J. F. , Blake J. B. , Shprits Y. Y.
Published: July 2016

We present a statistical analysis of phase space density data from the first 26 months of the Van Allen Probes mission. In particular, we investigate the relationship between the tens and hundreds of keV seed electrons and >1 MeV core radiation belt electron population. Using a cross‐correlation analysis, we find that the seed and core populations are well correlated with a coefficient of ≈0.73 with a time lag of 10–15 h. We present evidence of a seed population threshold that is necessary for subsequent acceleration. The depth of penetration of the seed population determines the inner boundary of the acceleration process. However, we show that an enhanced seed population alone is not enough to produce acceleration in the higher energies, implying that the seed population of hundreds of keV electrons is only one of several conditions required for MeV electron radiation belt acceleration.
Radiative convective equilibrium as a framework for studying the interaction between convection and its large‐scale environment
Authors: Silvers Levi G. , Stevens Bjorn , Mauritsen Thorsten , Giorgetta Marco
Published: July 2016

An uncertain representation of convective clouds has emerged as one of the key barriers to our understanding of climate sensitivity. The large gap in resolved spatial scales between General Circulation Models (GCMs) and high resolution models has made a systematic study of convective clouds across model configurations difficult. It is shown here that the simulated atmosphere of a GCM in Radiative Convective Equilibrium (RCE) is sufficiently similar across a range of domain sizes to justify the use of RCE to study both a GCM and a high resolution model on the same domain with the goal of improved constraints on the parameterized clouds. Simulations of RCE with parameterized convection have been analyzed on domains with areas spanning more than two orders of magnitude (
), all having the same grid spacing of
. The simulated climates on different domains are qualitatively similar in their degree of convective organization, the precipitation rates, and the vertical structure of the clouds and water vapor, with the similarity increasing as the domain size increases. Sea surface temperature perturbation experiments are used to estimate the climate feedback parameter for the differently configured experiments, and the cloud radiative effect is computed to examine the role which clouds play in the response. Despite the similar climate states between the domains the feedback parameter varies by more than a factor of two; the hydrological sensitivity parameter is better behaved, varying by a factor of 1.4. The sensitivity of the climate feedback parameter to domain size is related foremost to a nonsystematic response of low‐level clouds as well as an increasingly negative longwave feedback on larger domains.
Effects of explicit convection on global land‐atmosphere coupling in the superparameterized CAM
Authors: Sun Jian , Pritchard Michael S.
Published: July 2016

Conventional global climate models are prone to producing unrealistic land‐atmosphere coupling signals. Cumulus and convection parameterizations are natural culprits but the effect of bypassing them with explicitly resolved convection on global land‐atmosphere coupling dynamics has not been explored systematically. We apply a suite of modern land‐atmosphere coupling diagnostics to isolate the effect of cloud Superparameterization in the Community Atmosphere Model (SPCAM) v3.5, focusing on both the terrestrial segment (i.e., soil moisture and surface turbulent fluxes interaction) and atmospheric segment (i.e., surface turbulent fluxes and precipitation interaction) in the water pathway of the land‐atmosphere feedback loop. At daily timescales, SPCAM produces stronger uncoupled terrestrial signals (negative sign) over tropical rainforests in wet seasons, reduces the terrestrial coupling strength in the Central Great Plain in American, and reverses the coupling sign (from negative to positive) over India in the boreal summer season—all favorable improvements relative to reanalysis‐forced land modeling. Analysis of the triggering feedback strength (TFS) and amplification feedback strength (AFS) shows that SPCAM favorably reproduces the observed geographic patterns of these indices over North America, with the probability of afternoon precipitation enhanced by high evaporative fraction along the eastern United States and Mexico, while conventional CAM does not capture this signal. We introduce a new diagnostic called the Planetary Boundary Layer (PBL) Feedback Strength (PFS), which reveals that SPCAM exhibits a tight connection between the responses of the lifting condensation level, the PBL height, and the rainfall triggering to surface turbulent fluxes; a triggering disconnect is found in CAM.
MUF variability in the Arctic region: A statistical comparison with the ITU‐R variability factors
Authors: Athieno R. , Jayachandran P. T.
Published: July 2016

The maximum usable frequency (MUF(3000)F2) decile factors obtained from observations at five stations located in the Arctic region: Resolute (74.75°N, 265.10°E), Dikson (73.50°N, 80.40°E), Norilsk (69.40°N, 88.10°E), Loparskaya (68.00°N, 33.00°E), and Sodankyla (67.40°N, 26.60°E) have been compared with the International Telecommunication Union (ITU‐R) estimates over three solar cycles (1961–2013). The summer MUF(3000)F2 variability has been found to lie in the range of ±0.2, whereas limits for equinox and winter seasons are ±0.3 and ±0.5, respectively. This observation seems to directly translate into high differences between the measurement‐derived and ITU‐R decile values in winter and the smaller values for summer. These results illustrate that the high latitude ionosphere, and thus the MUF, is highly variable in winter, followed by the equinox, and experiences a low variability in summer.
Characterization of non‐Gaussian conductivities and porosities with hydraulic heads, solute concentrations, and water temperatures
Authors: Xu Teng , Gómez‐Hernández J. Jaime
Published: July 2016

Reliable characterization of hydraulic parameters is important for the understanding of groundwater flow and solute transport. The normal‐score ensemble Kalman filter (NS‐EnKF) has proven to be an effective inverse method for the characterization of non‐Gaussian hydraulic conductivities by assimilating transient piezometric head data, or solute concentration data. Groundwater temperature, an easily captured state variable, has not drawn much attention as an additional state variable useful for the characterization of aquifer parameters. In this work, we jointly estimate non‐Gaussian aquifer parameters (hydraulic conductivities and porosities) by assimilating three kinds of state variables (piezometric head, solute concentration, and groundwater temperature) using the NS‐EnKF. A synthetic example including seven tests is designed, and used to evaluate the ability to characterize hydraulic conductivity and porosity in a non‐Gaussian setting by assimilating different numbers and types of state variables. The results show that characterization of aquifer parameters can be improved by assimilating groundwater temperature data and that the main patters of the non‐Gaussian reference fields can be retrieved with more accuracy and higher precision if multiple state variables are assimilated.
Addendum zu Chlorierte Biphenyle [BAT Value Documentation in German language, 2016]
Authors: Rettenmeier A. , Kraus T. , Drexler H. , Hartwig A. ,   MAK‐Kommission
Published: July 2016

Chlorinated Biphenyls: Addendum BAT value documentation (2016)

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has evaluated chlorinated biphenyls and has derived a biological tolerance value at the work place (BAT value) for the combined plasma levels of the PCB congeners 28, 52, 101, 138, 153 and 180. Available publications are described in detail.

The evaluation of the BAT value was based on studies in rats and has therefore to be regarded as preliminary. In a 2‐year NTP study of PCB 153 in female SD rats, a NOAEL of 10 µg/kg body weight was observed. Liver hypertrophy was the critical toxic effect. The mean blood concentration of PCB 153 was 17.4 µg/l. After extrapolation to humans and considering the non‐dioxin‐like indicator congeners, a BAT value for the combined plasma concentrations of PCB 28, 52, 101, 138, 153 and 180 of 15 µg/l was established. A specific sampling time is not required.

The „Biologische Arbeitsstoff‐Referenzwerte” (BAR) in plasma of 0.02 µg/l for PCB 28, <0.01 µg/l for PCB 52, and <0.01 µg/l for PCB 101 were reconfirmed. Exceeding the BAR indicates additional occupational exposure.
Addendum zu Arsen und anorganische Arsenverbindungen (mit Ausnahme von Arsenwasserstoff) [BAT Value Documentation in German language, 2016]
Authors: Ochsmann E. , Göen T. , Michalke B. , Weistenhöfer W. , Klotz K. , Drexler H. , Hartwig A. ,   MAK‐Kommission
Published: July 2016

Arsenic and inorganic arsenic compounds (with the exception of arsenic hydride): BAT value documentation (2016)

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated the “Biologischer Arbeitsstoff‐Referenzwert” (BAR) as well as the exposure equivalents for carcinogenic substances (EKA) for arsenic and inorganic arsenic compounds (with the exception of arsenic hydride). Available publications are described in detail.

The quantification of the various arsenic species is essential to understand the hazardous potential of the arsenic compounds which differ highly in their toxicity. Therefore the BAR for the sum of different arsenic species is no longer valid. Considering published data from occupational not exposed persons, new BAR for the arsenic species of 0.5 μg/l urine for arsenic (+III), 0.5 μg/l urine for arsenic (+V), 2 μg/l urine for monomethylarsonic acid (MMA) and 10 μg/l urine for dimethylarsinic acid (DMA) were evaluated. The differentiation of arsenic species now allows for the estimation of the individual health risks taking into account special influences like seafood consumption. Sampling time is at the end of exposure or the end of the working shift and after long term exposure at the end of the working shift after several shifts.

Data of a correlation of arsenic in the air and the sum of the arsenic species in urine were considered for the evaluation of the exposure equivalents for carcinogenic substances. This correlation is in good accordance with the EKA correlation of arsenic trioxide, which is based on former studies in which also the urinary concentrations of the sum of As (+III), As (+V), MMA and DMA were measured. Sampling time is at the end of exposure or the end of the working shift and after long term exposure at the end of the working shift after several shifts.
3‐Methyl‐5‐isopropylhydantoin als Hämoglobinaddukt desN,N‐Dimethylformamids und Methylisocyanats [Biomonitoring Methods in German Language, 2015]
Authors: Käfferlein H. U. , Angerer J. , Leng G. , Gries W. , Hartwig A. ,   MAK Commission
Published: July 2016

The analytical method describes the specific determination of 3‐methyl‐5‐isopropylhydantoin (MIH), a hemoglobin adduct of N,N‐dimethylformamide. Following addition of13C5,15N‐3‐methyl‐5‐isopropylhydantoin (13C5,15N‐MIH) as internal standard, isolated globin is subjected to acid hydrolysis for one hour at 110deg;C. After pH adjustment (pH 3–5) the hydrolysate is extracted twice with ethyl acetate. The combined extracts are washed with sodium hydrogen carbonate solution and dried under a stream of nitrogen. The residue is dissolved in ethyl acetate. An aliquot of the solution is analyzed using GC–MS. For calibration purposes, calibration standards are prepared in pooled globin. They are processed in the same way as the samples to be analyzed.
N‐Methylformamid undN‐Methylacetamid in Urin [Biomonitoring Methods in German Language, 2015]
Authors: Will W. , Göen T. , Hartwig A. ,   MAK Commission
Published: July 2016

The present method allows for the determination of the main metabolites of N,N‐dimethylformamide and N,N‐dimethylacetamide in urine: HMMF, NMF, HMMA and NMA, respectively. HMMF and HMMA readily decompose thermally to form N‐methylformamide (NMF) or N‐methylacetamide (NMA) and formaldehyde. Prior to sample injection, thermolysis is carried out for 2 hours at 120°C in order to transform the metabolites completely into the target analytes NMF and NMA. The urine samples are then diluted with ethanol and analyzed using GC–MS. Thus, the sum of HMMF and NMF (DMF metabolites) and the sum of HMMA and NMA (DMA metabolites), respectively, are detected by this procedure.
Arsenic and its Inorganic Compounds (with the Exception of Arsine) [MAK Value Documentation, 2014]
Authors: Hartwig A. ,   MAK Commission
Published: July 2016

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated arsenic and its inorganic compounds, with a special focus on gallium arsenide. Available publications and study reports are described in detail.

Arsenic and its inorganic compounds are carcinogenic in humans. From the available studies in workers in the semiconductor industry probably exposed to gallium arsenide, no increased cancer risk can be derived. Carcinogenicity studies with inhalation exposure to gallium arsenide revealed lung tumours, mononuclear leukaemia and benign phaeochromocytomas in the adrenal glands in female rats. In animal studies, increased levels of arsenic in blood were determined after exposure to gallium arsenide. The metabolites are the same as those found after exposure to arsenite and arsenate. Although the bioavailability of gallium arsenide is much lower than that of arsenic trioxide, it cannot be completely neglected. Therefore, the classification of arsenic and its inorganic compounds including gallium arsenide as carcinogenic in man (Carcinogen Category 1) has been retained.

In vitro genotoxicity studies with inorganic arsenic(III) compounds yielded mostly positive results in tests for sister chromatid exchange, chromosomal aberrations and micronuclei. In in vivo studies with somatic cells, arsenic(III) compounds induced an increase in DNA strand breaks, chromosomal aberrations and micronuclei. In humans exposed long‐term to arsenic, increased incidences of micronuclei, chromosomal aberrations, sister chromatid exchange and DNA damage were observed. Gallium arsenide was not genotoxic in vitro and in vivo. Gallium arsenide, like arsenic, is systemically available and forms the same metabolites as arsenic and its inorganic compounds. For this reason the suspected germ cell mutagenicity of gallium arsenide cannot be unequivocally excluded. Arsenic and its inorganic compounds including gallium arsenide therefore remain in Category 3A for germ cell mutagens which produce mutagenic effects in somatic cells of mammals in vivo and have been shown to reach the germ cells.

No MAK value has been derived and thus also no peak limitation has been established, and classification into one of the Pregnancy Risk Groups is not possible. Skin contact is not expected to contribute significantly to systemic toxicity. Sensitizing effects of arsenic and its inorganic compounds cannot be derived from the available data.
Color Tuning of Avobenzone Boron Difluoride as an Emitter to Achieve Full‐Color Emission
Authors: Mo Hin‐Wai , Tsuchiya Youichi , Geng Yan , Sagawa Takehiro , Kikuchi Chika , Nakanotani Hajime , Ito Fuyuki , Adachi Chihaya
Published: July 2016

Organic light‐emitting diodes (OLEDs) displaying a wide range of emission colors with emission peaks from 450 to 665 nm using a single emitting material, avobenzone boron difluoride (AVB‐BF2), are reported. Color tuning is achieved by controlling the aggregation of AVB‐BF2 and the formation of a “triadic” exciplex of an AVB‐BF2 dimer and a host molecule. Various electroluminescent devices containing AVB‐BF2 cover the whole visible light spectrum and a white‐emitting device with CIE coordinates of (0.35, 0.37) is obtained with a single emitting material in a single emissive layer. Furthermore, an exceptionally high external quantum efficiency of nearly 13% is achieved for a green‐emitting OLED because AVB‐BF2 exhibits thermally activated delayed fluorescence by forming the exciplex.
Mesoporous Piezoelectric Polymer Composite Films with Tunable Mechanical Modulus for Harvesting Energy from Liquid Pressure Fluctuation
Authors: Zhang Zhiyi , Yao Chunhua , Yu Yanhao , Hong Zhanglian , Zhi Mingjia , Wang Xudong
Published: July 2016

Harvesting mechanical energy from biological systems possesses great potential for in vivo powering implantable electronic devices. In this paper, a development of flexible piezoelectric nanogenerator (NG) is reported based on mesoporous poly(vinylidene fluoride) (PVDF) films. Monolithic mesoporous PVDF is fabricated by a template‐free sol–gel‐based approach at room temperature. By filling the pores of PVDF network with poly(dimethylsiloxane) (PDMS) elastomer, the composite's modulus is effectively tuned over a wide range down to the same level of biological systems. A close match of the modulus between NG and the surrounding biological component is critical to achieve practical integration. Upon deformation, the composite NG exhibits appreciable piezoelectric output that is comparable to or higher than other PVDF‐based NGs. An artificial artery system is fabricated using PDMS with the composite NG integrated inside. Effective energy harvesting from liquid pressure fluctuation (simulating blood pressure fluctuation) is successfully demonstrated. The simple and effective approach for fabricating mesoporous PVDF with tunable mechanical properties provides a promising route toward the development of self‐powered implantable devices.
2D Materials Beyond Graphene for High‐Performance Energy Storage Applications
Authors: Zhang Xiaoyan , Hou Lili , Ciesielski Artur , Samorì Paolo
Published: July 2016

Energy crisis is one of the most urgent and critical issues in our modern society. Currently, there is an increasing demand for efficient, low‐cost, light‐weight, flexible and environmentally benign, small‐, medium‐, and large‐scale energy storage devices, which can be used to power smart grids, portable electronic devices, and electric vehicles. Novel electrode materials, with a high energy density at high power are urgently needed for realizing high‐performance energy storage devices. The recent development in the field of 2D materials, including both graphene and other layered systems, has shown promise for a wide range of applications. In particular, graphene analogues, due to their remarkable electrochemical properties, have shown great potential in energy‐related applications. This review aims at providing an overview of current research and important advances on the development of 2D materials beyond graphene for supercapacitors and batteries. The major challenges to be tackled, and more generally the future directions in the field, are also highlighted.
Visibly‐Transparent Organic Solar Cells on Flexible Substrates with All‐Graphene Electrodes
Authors: Song Yi , Chang Sehoon , Gradecak Silvija , Kong Jing
Published: July 2016

Portable electronic devices have become increasingly widespread. Because these devices cannot always be tethered to a central grid, powering them will require low‐cost energy harvesting technologies. As a response to this anticipated demand, this study demonstrates transparent organic solar cells fabricated on flexible substrates, including plastic and paper, using graphene as both the anode and cathode. Optical transmittance of up to 69% at 550 nm is achieved by combining the highly transparent graphene electrodes with organic polymers that primarily absorb in the near‐IR and near‐UV regimes. To address the challenge of transferring graphene onto organic layers as the top electrode, this study develops a room temperature dry‐transfer technique using ethylene‐vinyl‐acetate as an adhesion‐promoting interlayer. The power conversion efficiency achieved for flexible devices with graphene anode and cathode devices is 2.8%–3.8% at for optical transmittance of 54%–61% across the visible regime. These results demonstrate the versatility of graphene in optoelectronic applications and it is important step toward developing a practical power source for distributed wireless electrical systems.
Systematic Investigation of Porphyrin‐Thiophene Conjugates for Ternary Bulk Heterojunction Solar Cells
Authors: Keawsongsaeng Wittawat , Gasiorowski Jacek , Denk Patrick , Oppelt Kerstin , Apaydin Dogukan H. , Rojanathanes Rojrit , Hingerl Kurt , Scharber Markus , Sariciftci Niyazi Serdar , Thamyongkit Patchanita
Published: July 2016

A family of porphyrins and benzoporphyrins bearing phenyl, thiophenyl, or bithiophenyl groups at their meso‐positions are synthesized and systematically investigated for their potential use in bulk heterojunction solar cells (BHJ‐SCs). Comparative studies of these compounds show that the introduction of the thiophenyl and bithiophenyl groups, and the extension of the porphyrin π‐conjugated system significantly affect both photophysical and electrochemical properties. Binary conventional and ternary converted BHJ‐SCs based on these compounds are fabricated and studied. Results show that remarkable enhancement of the device efficiency is achieved by using the thiophene‐containing benzoporphyrin derivatives as additives for a poly(3‐hexylthiophene) (P3HT):phenyl‐C61‐butyric acid methyl ester blend in the inverted BHJ‐SCs. The optimum BHJ‐SC exhibits a maximum energy conversion efficiency of 4.3%, corresponding to 19% enhancement of the conversion efficiency as compared with the benchmark BHJ‐SCs.
A Novel Sustainable Flour Derived Hierarchical Nitrogen‐Doped Porous Carbon/Polyaniline Electrode for Advanced Asymmetric Supercapacitors
Authors: Yu Pingping , Zhang Zhiming , Zheng Lingxia , Teng Feng , Hu Linfeng , Fang Xiaosheng
Published: July 2016

Hierarchically porous nitrogen‐doped carbon (HPC)/polyaniline (PANI) nanowire arrays nanocomposites are synthesized by a facile in situ polymerization. 3D interconnected honeycomb‐like HPC was prepared by a cost‐effective route via one‐step carbonization using urea and alkali‐treated wheat flour as carbon precursor with a high specific surface area (1294 m2 g−1). The specific capacitances of HPC and HPC/PANI (with a surface area of 923 m2 g−1) electrode are 383 and 1080 F g−1 in 1 m H2SO4, respectively. Furthermore, an asymmetric supercapacitor based on HPC/PANI as positive electrode and HPC as negative electrode is successfully assembled with a voltage window of 0–1.8 V in 1 m Na2SO4 aqueous electrolyte, exhibiting high specific capacitance (134 F g−1), high energy density (60.3 Wh kg−1) and power density (18 kW kg−1), and excellent cycling stability (91.6% capacitance retention after 5000 cycles).
Heritability of major depressive and comorbid anxiety disorders in multi‐generational families at high risk for depression
Authors: Guffanti Guia , Gameroff Marc J. , Warner Virginia , Talati Ardesheer , Glatt Charles E. , Wickramaratne Priya , Weissman Myrna M.
Published: July 2016

Family studies have shown that MDD is highly transmittable but have not studied its heritability. Twin studies show heritability of about 40% and do not include anxiety disorders. We assessed heritability of MDD and comorbid anxiety disorders in a multigenerational study of family members at high risk for MDD. In addition, we tested the hypothesis that examined clinical subtypes of MDD defined by early and late age of onset would be under relatively stronger genetic control than broadly defined DSM‐IV MDD. The first generation with moderate to severe MDD was recruited from an ambulatory psychiatric treatment setting, and their descendants in the second, third, and fourth generation, were interviewed by clinicians up to six times during a 30‐year period. Lifetime rates of MDD and anxiety disorders were collected for 545 participants from 65 multigenerational families. The heritability (h2) of MDD in this high risk sample was estimated at 67%. Anxiety and sequential comorbidity of anxiety disorders and MDD revealed h2 of 49% and 53%, respectively, and strong positive genetic correlation (rhog = 0.92, P = 7.3 × 10−7). Early onset MDD did not appear to be under greater genetic control than broadly defined DSM‐IV MDD. Individuals who are direct descendants of subjects ascertained for moderate to severe MDD have strong genetic vulnerability to develop anxiety or MDD. Our findings support family based studies as appropriate and useful design to understand the heritability of common disorders such as MDD. © 2016 Wiley Periodicals, Inc.
Synthesis, characterization, photoluminescence and electrochemical properties of Pt(II) and Ag(I) complexes of tetradentate aminomethylphosphine ligands and antiproliferative activities on HT‐29 human colon cancer
Authors: Uruş Serhan , İncesu Mahmut , Köşker Seda , Kurt Akif Hakan , Ceyhan Gökhan
Published: July 2016

Novel N1,N1,N4,N4‐tetrakis((diphenylphosphino)methyl)benzene‐1,4‐diamine (L1), N1,N1,N5,N5‐tetrakis((diphenylphosphino)methyl)naphthalene‐1,5‐diamine (L2) and 4,4′‐methylenebis(N,N‐bis((diphenylphosphino)methyl)aniline) (L3) ligands and their Pt(II) and Ag(I) complexes have been synthesized under nitrogen atmosphere using the Schlenk technique. The ligands and the complexes were characterized using 1H NMR, 31P NMR and Fourier transform infrared spectroscopies, thermogravimetric/differential thermal analysis, elemental analysis (C, H, N), inductively coupled plasma optical emission spectrometry (metal content), cyclic voltammetry and photoluminescence. All the complexes were investigated as anticancer agents on HT‐29 human colon cancer cell line. HT‐29 cells were treated with various concentrations (10, 25, 50, 100, 250 μM) of Pt(II) and Ag(I) tetrakisditertiaryaminomethylphosphine complexes. Cisplatin was tested at the same concentrations in order to compare the antiproliferative activities of the synthesized Pt(II) and Ag(I) complexes. Pt(II) complexes of L1 and L3 and Ag(I) complexes of L1, L2 and L3 showed a similar inhibition effect of cancer cell proliferation when compared to cisplatin up to 50 μM; at 100 μM and higher concentrations, L1–Pt(II) and L3–Ag(I) complexes showed a much greater effect than cisplatin. Copyright © 2016 John Wiley & Sons, Ltd.
Structurally rigid bis(pyrazolyl)pyridine Zn(II) and Cu(II) complexes: Structures and kinetic studies in ring‐opening polymerization of ε‐caprolactone
Authors: Zikode Mnqobi , Ojwach Stephen O. , Akerman Matthew P.
Published: July 2016

Four bis(pyrazolyl)pyridine Zn(II) and Cu(II) carboxylate complexes have been structurally elucidated and used as initiators in the ring‐opening polymerization (ROP) of ε‐carprolactone (ε‐CL). Reactions of bis(3,5‐dimethyl‐pyrazol‐1‐yl)pyridine (L1) with the appropriate Zn(II) and Cu(II) carboxylates afforded the corresponding complexes; [Zn(L1)(C6H5COO)2] (1), [Zn(L1)(2‐Cl‐C6H4COO)2] (2), [Zn(L1)(OAc)2] (3) and [Cu(L1)(OAc)2] (4) in moderate to good yields. Molecular structures of compounds 1, 2, 3 confirmed the presence of one tridentate bound ligand L1 in the metal coordination sphere and two carboxylate anions to give five coordination number around Zn(II) and Cu(II) atoms. Complexes 1, 2, 3, 4 initiated the ROP of ε‐CL at 110 °C to give polymers of moderate molecular weights. Kinetic analyses of the ROP reactions indicate pseudo‐first‐order dependency on ε‐CL monomer and initiator. 1H NMR and mass spectral data established a coordination insertion mechanistic pathway and behaviour of 1, 2, 3, 4 as initiators in the ROP of ε‐CL. Copyright © 2016 John Wiley & Sons, Ltd.
Improved Robust Stability Criteria for Time‐Delay Lur'e System
Authors: Duan Wenyong , Fu Xiaorong , Liu Zhengfan , Yang Xiaodong
Published: July 2016

This paper deals with the problem of the robustly absolute stability for neutral‐type Lur'e systems with mixed time‐varying delay. By combining the piecewise analysis theory with the reciprocally convex method and Wirtinger‐based inequality technology, some new delay‐dependent stability criteria are proposed via a modified Lyapunov‐Krasovskii functional (LKF) approach. The stability conditions can be solved by using standard linear matrix inequality (LMI) convex optimization solvers. The criteria are less conservative than some previous ones. Three numerical examples are presented to show the effectiveness of the proposed approach.
Inflating transform matrices to mitigate assimilation errors with robust filtering based ensemble Kalman filters
Authors: Bai Yulong , Zhang Zhuanhua , Zhang Yanli , Wang Lili
Published: July 2016

An error covariance matrix plays an important role in maintaining the statistical property of the ensemble in an ensemble Kalman filter method. However, data assimilation filter divergence may occur from an inaccurate estimate of the covariance matrix. In this study, based on an ensemble time‐local H‐infinity filter, which inflates the eigenvalues of the analysis error covariance matrix, a new robust ensemble data assimilation method is proposed, referred to as an inflation transform matrix eigenvalues. By design, new filters may be preferred over other traditional ensemble filters, when model performances are not well known, or change unpredictably. The primary aim is to improve the performance of the assimilation system in the framework of the ensemble filtering, according to the minimum/maximum rule of robust filtering. The proposed estimation method is tested using the well‐known Lorenz‐96 model, in order to investigate how the ensemble time‐local H‐infinity filter method of the inflation transform matrix impacts the robustness of the assimilation system under selected special conditions, such as the assimilation steps, force parameters, ensemble sizes, and observation information. The experiments show that the proposed inflation transform matrix method displays good robustness to the changes in the system's parameters. Also, when compared with the traditional filtering methods, this robust filtering method is found to improve the assimilation performance.
Visual orienting in children with autism: Hyper‐responsiveness to human eyes presented after a brief alerting audio‐signal, but hyporesponsiveness to eyes presented without sound
Authors: Kleberg Johan Lundin , Thorup Emilia , Falck‐Ytter Terje
Published: July 2016

Autism Spectrum Disorder (ASD) has been associated with reduced orienting to social stimuli such as eyes, but the results are inconsistent. It is not known whether atypicalities in phasic alerting could play a role in putative altered social orienting in ASD. Here, we show that in unisensory (visual) trials, children with ASD are slower to orient to eyes (among distractors) than controls matched for age, sex, and nonverbal IQ. However, in another condition where a brief spatially nonpredictive sound was presented just before the visual targets, this group effect was reversed. Our results indicate that orienting to social versus nonsocial stimuli is differently modulated by phasic alerting mechanisms in young children with ASD. Autism Res 2017, 10: 246–250. © 2016 The Authors Autism Research published by Wiley Periodicals, Inc. on behalf of International Society for Autism Research.
Enhanced integration of large DNA into E. coli chromosome by CRISPR/Cas9
Authors: Chung Mu‐En , Yeh I‐Hsin , Sung Li‐Yu , Wu Meng‐Ying , Chao Yun‐Peng , Ng I‐Son , Hu Yu‐Chen
Published: July 2016

Metabolic engineering often necessitates chromosomal integration of multiple genes but integration of large genes into Escherichia coli remains difficult. CRISPR/Cas9 is an RNA‐guided system which enables site‐specific induction of double strand break (DSB) and programmable genome editing. Here, we hypothesized that CRISPR/Cas9‐triggered DSB could enhance homologous recombination and augment integration of large DNA into E. coli chromosome. We demonstrated that CRISPR/Cas9 system was able to trigger DSB in >98% of cells, leading to subsequent cell death, and identified that mutagenic SOS response played roles in the cell survival. By optimizing experimental conditions and combining the λ‐Red proteins and linear dsDNA, CRISPR/Cas9‐induced DSB enabled homologous recombination of the donor DNA and replacement of lacZ gene in the MG1655 strain at efficiencies up to 99%, and allowed high fidelity, scarless integration of 2.4, 3.9, 5.4, and 7.0 kb DNA at efficiencies approaching 91%, 92%, 71%, and 61%, respectively. The CRISPR/Cas9‐assisted gene integration also functioned in different E. coli strains including BL21 (DE3) and W albeit at different efficiencies. Taken together, our methodology facilitated precise integration of dsDNA as large as 7 kb into E. coli with efficiencies exceeding 60%, thus significantly ameliorating the editing efficiency and overcoming the size limit of integration using the commonly adopted recombineering approach. Biotechnol. Bioeng. 2017;114: 172–183. © 2016 Wiley Periodicals, Inc.
Evaluative Diversity and the Board
Authors: Santos‐Lang Chris
Published: July 2016

In the second article of this issue of Board Leadership addressing the board's job of creating both plurality and unity, Chris Santos‐Lang introduces the concept of evaluative diversity.
Effect of amino acid supplementation on titer and glycosylation distribution in hybridoma cell cultures—Systems biology‐based interpretation using genome‐scale metabolic flux balance model and multivariate data analysis
Authors: Reimonn Thomas M. , Park Seo‐Young , Agarabi Cyrus D. , Brorson Kurt A. , Yoon Seongkyu
Published: July 2016

Genome‐scale flux balance analysis (FBA) is a powerful systems biology tool to characterize intracellular reaction fluxes during cell cultures. FBA estimates intracellular reaction rates by optimizing an objective function, subject to the constraints of a metabolic model and media uptake/excretion rates. A dynamic extension to FBA, dynamic flux balance analysis (DFBA), can calculate intracellular reaction fluxes as they change during cell cultures. In a previous study by Read et al. (2013), a series of informed amino acid supplementation experiments were performed on twelve parallel murine hybridoma cell cultures, and this data was leveraged for further analysis (Read et al., Biotechnol Prog. 2013;29:745–753). In order to understand the effects of media changes on the model murine hybridoma cell line, a systems biology approach is applied in the current study. Dynamic flux balance analysis was performed using a genome‐scale mouse metabolic model, and multivariate data analysis was used for interpretation. The calculated reaction fluxes were examined using partial least squares and partial least squares discriminant analysis. The results indicate media supplementation increases product yield because it raises nutrient levels extending the growth phase, and the increased cell density allows for greater culture performance. At the same time, the directed supplementation does not change the overall metabolism of the cells. This supports the conclusion that product quality, as measured by glycoform assays, remains unchanged because the metabolism remains in a similar state. Additionally, the DFBA shows that metabolic state varies more at the beginning of the culture but less by the middle of the growth phase, possibly due to stress on the cells during inoculation. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1163–1173, 2016
Identification and Structural Analysis of New Nrf2 Activators by Mechanism‐Based Chemical Transformation of 15‐Deoxy‐Δ12, 14‐PGJ2
Authors: Kim Kyeojin , Park Jong‐Min , Kim Nam‐Jung , Kim Su‐Jung , Moon Hyunyoung , An Hongchan , Lee Jeeyeon , Park Hyun‐Ju , Surh Young‐Joon , Suh Young‐Ger
Published: July 2016

Mechanism‐based chemical transformation of 15‐deoxy‐Δ12, 14‐PGJ2 (15d‐PGJ2) resulted in a series of new NF‐E2‐related factor‐2 (Nrf2) activators and detailed elucidation of the function of each electrophilic binding site. In addition, HO‐1 expression resulting from Nrf2 activation through enhanced dissociation of the Keap1–Nrf2 complex by the new activators was proved.
Cryopreserved hepatic progenitor cells derived from human embryonic stem cells can arrest progression of liver fibrosis in rats
Authors: Mandal Arundhati , Raju Sheena , Viswanathan Chandra
Published: July 2016

Hepatocytes generated from human embryonic stem cells (hESCs) are considered to be an excellent candidate for restoring the liver function deficiencies. We have earlier standardized a three‐step differentiation protocol to generate functional hepatocyte‐like cells (HLCs) from hESCs, which expressed the major hepatic markers. We have also found that the HLCs remain stable and functional even after extended period of in vitro culture and cryopreservation. In the present study, we have aimed to investigate the therapeutic potential of cryopreserved‐thawed hESC‐derived hepatic progenitor cells following transplantation in carbon tetrachloride‐induced fibrotic rat livers. Significant therapeutic effects, including improved hepatic histology and normal serum biochemistry of hepatic enzymes along with increased survival rate, were observed in the cell transplanted rats. This result is an encouraging indication to develop methods for clinical application of hESC‐derived hepatic lineage cells.
Rab proteins as regulators of lipid droplet formation and lipolysis
Authors: Li Chunman , Yu Sidney S. B.
Published: July 2016

Lipid droplets (LDs) are highly dynamic organelles that not only store neutral lipids but also are involved in multiple cellular processes. Dysregulation of lipogenesis or lipolysis greatly contributes to the pathogenesis of several human diseases, including obesity, diabetes, and fatty liver disease. Rab proteins have been found to be associated with LDs in proteomic studies and are also known to extensively regulate intracellular membrane traffic, suggesting that LDs actively communicate with other membrane compartments to maintain energy homeostasis. This review discusses recent studies that provide mechanistic insights into the regulation of LD formation and catabolism by Rab proteins in mammalian cells.
An Efficient Electrocatalyst Derived from Bamboo Leaves for the Oxygen Reduction Reaction
Authors: Zhang Lian Ying , Zhou Zhiqin , Liu Ze , Li Chang Ming
Published: July 2016

Bamboo leaves are carbonized and tailored into an efficient electrocatalyst as an alternative to noble‐metal‐based catalysts of oxygen reduction. Surprisingly, in comparison to the commercial Pt/C, the as‐prepared catalyst shows higher methanol tolerance, resistance to CO poisoning and stability, and similar electrocatalytic activity. The high electrocatalytic activity probably arises from the hierarchical porous structure for fast mass transport and its inherently existing N, S or Fe as efficient catalytic sites. This work offers a facile approach to use inexpensive biomass as a promising and inexpensive electrocatalyst material in fuel cell applications, and suggests a performance‐enhancement mechanism for the biomass‐derived catalyst.
Fault diagnosis of chemical processes considering fault frequency via Bayesian network
Authors: Askarian Mahdieh , Zarghami Reza , Jalali‐Farahani Farhang , Mostoufi Navid
Published: July 2016

In the present study, data‐driven fault diagnosis (FD) systems of chemical plants dealing with frequent and rare faults are investigated. Although different faults occur with different frequencies in chemical plants, this issue has scarcely been addressed in developing a process FD system. A novel diagnostic framework based on the Bayesian network (BN) is proposed to incorporate fault frequencies. This probabilistic method can readily involve non‐uniform probability distribution of faults and non‐Gaussian probability distribution of features. The proposed approach includes not only a combination of tools but also information management. In fact, the imbalanced dataset, established by frequent and rare faults, promotes recursive updating of prior probabilities of faults. The performance of the BN was evaluated and compared with the conventional C4.5 method in the Tennessee‐Eastman process benchmark. It was shown in this work that the diagnostic performance of the proposed approach versus the C4.5 method is more efficient. The importance of taking into account non‐uniform probability distribution of faults for designing a FD system was highlighted. Furthermore, the effect of independent component analysis (ICA) of the imbalanced dataset on the FD was examined. The proposed framework versus the C4.5 method promises 37 % FD performance improvement for the dataset with a 10:1 imbalance index.
KDP single crystal growth via three‐dimensional motion growth method
Authors: Yin Huawei , Li Mingwei , Zhou Chuan , Song Jie
Published: July 2016

A novel system for rapid crystal growth, namely three‐dimensional motion growth method (“3D MGM”) was proposed. Using this system, a potassium dihydrogen phosphate (KDP) seed was grown to a single crystal with a final size of 50×55×85 mm3. The KDP crystal was characterized by Raman spectroscopy, UV‐vis‐NIR spectroscopy, extinction ratio, laser damage threshold, and etching studies. Raman spectrum shows KDP crystal grown by “3D MGM” maintains good crystallinity as that grown by rotating‐crystal method (“RCM”). The “3D MGM” grown KDP crystal has much better transmittance, higher extinction ratio, higher damage threshold and less dislocation density, compared to “RCM” grown crystal.
Formation mechanisms of tripod and tetrapod CdTe0.67Se0.33 nanocrystals
Authors: Liu X. H. , Wang C. , Duan X. F. , Wang Y. Q. , Liu G. J. , Diao F. Y. , Yang P. , Zhang J. P.
Published: July 2016

CdTe0.67Se0.33 nanocrystals were synthesized using a typical organic route. Two major morphologies are observed from transmission electron microscopy (TEM) images, one being a tripod, and the other being a tripod‐like with a black dot in the center of the nanocrystal. The nanocrystals have two distinct geometrical shapes, one being a tripod, and the other being a tetrapod. High‐resolution TEM (HRTEM) examinations show that the tetrapod nanocrystals consist of a zinc‐blende nucleus and four wurtzite arms connected through a common facet, whereas the tripod nanocrystals result from the coalescence of three zinc‐blende nanorods. These results are helpful to interpret the growth process of other II–VI semiconductor NCs.
Tailored Combination of Low Dimensional Catalysts for Efficient Oxygen Reduction and Evolution in Li–O2 Batteries
Authors: Yoon Ki Ro , Kim Dae Sik , Ryu Won‐Hee , Song Sung Ho , Youn Doo‐Young , Jung Ji‐Won , Jeon Seokwoo , Park Yong Joon , Kim Il‐Doo
Published: July 2016

The development of efficient bifunctional catalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is a key issue pertaining high performance Li–O2 batteries. Here, we propose a heterogeneous electrocatalyst consisting of LaMnO3 nanofibers (NFs) functionalized with RuO2 nanoparticles (NPs) and non‐oxidized graphene nanoflakes (GNFs). The Li–O2 cell employing the tailored catalysts delivers an excellent electrochemical performance, affording significantly reduced discharge/charge voltage gaps (1.0 V at 400 mA g−1), and superior cyclability for over 320 cycles. The outstanding performance arises from (1) the networked LaMnO3 NFs providing ORR/OER sites without severe aggregation, (2) the synergistic coupling of RuO2 NPs for further improving the OER activity and the electrical conductivity on the surface of the LaMnO3 NFs, and (3) the use of GNFs providing a fast electronic pathway as well as improved ORR kinetics.