bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Nitrogen Form on Simazine Accumulation in Corn, Soybeans, and Rye
Authors: McReynolds William D. , Tweedy James A.
Published: June 2019

Carbon-14-labeled 2-chloro-4,6-bis(ethylamino)-s-trazine (simazine) was applied at a low concentration to the root media of rye (Secale cerealeL.), soybean (Glycine maxL.), and corn (Zea maysL.) plants growing in nutrient solution that contained nitrate or ammonium nitrogen. The shoots of the plants grown on nitrate nitrogen contained more radioactive simazine per unit fresh weight than the plants that were grown on ammonium nitrogen. Less herbicidal injury was observed on soybean plants grown in soil fertilized with ammonium sulfate than on soybean plants fertilized with calcium nitrate.
Control of Wild Cane in Corn
Authors: Burnside O. C.
Published: June 2019

The most effective and dependable method of controlling wild cane [Sorghum bicolor (L.) Moench] in corn (Zea mays L.) was with a combination of cultivation plus herbicides. Timely cultivations were equally or more effective than preplant herbicides in controlling wild cane, but neither method was adequate by itself. The best herbicide in this study for the control of wild cane in corn was S-ethyl dipropylthiocarbamate (EPTC) alone or in combination with (2,4-dichlorophenoxy)acetic acid (2,4-D) or 2-chloro-4,6-bis-(ethylamino)-s-triazine (simazine). Residual effects of simazine at 4 lb/A in the soil reduced the yield of the following oats (Avena sativa L.) crop 1 out of 3 years.
Reaction of Wheat to Picloram
Authors: Nalewaja John D.
Published: June 2019

Wheat (Triticum aestivum L., var. Selkirk) was most susceptible at the late tiller stage to 4-amino-3,5,6-trichloropicolinic acid (picloram) as determined from weekly applications in the field and the degree of injury increased with rate of picloram. Wheat injury from picloram was manifested by lower kernel yield, greater protein content in the kernels, and reduction in plant height. A reduction in the length of the stem occurred while the length of the flag leaf sheath was not affected. Picloram increased kernel size in 1966 but reduced it in 1965. Picloram did not influence germination of kernels from treated plants. The addition of (2,4-dichlorophenoxy)acetic acid (2,4-D) to picloram tended to increase wheat injury at the 2 to 4-leaf stage.
An Implanted Soil Mass Technique to Study Herbicide Effects on Root Growth
Authors: Lund Zane F. , Pearson R. W. , Buchanan Gale A.
Published: June 2019

An implanted soil mass technique was modified to study the effect of soil-incorporated herbicides on root growth. The technique was used to study the effects of α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine (trifluralin) and 4-(methylsulfonyl)-2,6-dinitro-N,N-dipropylaniline (nitralin) on root growth of cotton (Gossypium hirsutumL., var. Auburn 56) and the effects of trifluralin andS-propyl dipropylthiocarbamate (vernolate) on soybeans (Glycine max(L.) Merr., var. Bragg). Vernolate had no effect, but there was only 57% as much soybean root tissue in the soil receiving 1 ppm of trifluralin as there was in the untreated check 2 months after initiating the treatments. Trifluralin and nitralin at 1 ppm reduced cotton roots to 75% and 50%, respectively, of that of the untreated check. The effects of trifluralin and low soil pH were additive, but there was no interaction between them.
Selective Weed Control in Seedling Cool-Season Grasses
Authors: Canode C. L. , Robocker W. C.
Published: June 2019

Seven herbicides were applied for selective weed control on three different seedling stands of five cool-season grasses. The herbicides were evaluated for their influence on weed control, grass establishment, and first crop grass seed production. These experiments indicate that 3,5-dibromo-4-hydroxybenzonitrile (bromoxynil) was outstanding in selective control of broadleaf weeds in seedling grass stands. Two other herbicides, 3,6-dichloro-o-anisic acid (dicamba) and 6,7-dihydrodipyrido[1,2-a:2′,1′-c]pyrazinediium ion (diquat) were valuable under most conditions. The remaining herbicides—(2,4-dichlorophenoxy)acetic acid (2,4-D), 2-sec-butyl-4,6-dinitrophenol (dinoseb), 2,3,6-trichlorobenzoic acid (2,3,6-TBA), and 1-butyl-3-(3,4-dichlorophenyl)-1-methylurea (neburon)—were satisfactory for selective weed control under some conditions, but their effects were not uniform for the different species and plantings.
Pine Seedling Response to Dichlobenil, Fluometuron, and Pebulate
Authors: Wilkinson R. E. , Davis T. S.
Published: June 2019

Growth and percentage survival was measured for slash pine (Pinus elliottii Engelm.), shortleaf pine (P. echinata Mill.), Virginia pine (P. virginiana Mill.), and loblolly pine (P. taeda L.) seedlings treated with: (a) 0.07 to 4.48 kg/ha 2,6-dichlorobenzonitrile (dichlobenil), (b) 0.28 to 8.96 kg/ha 1,1-dimethyl-3-(a,a,a-trifluoro-m-tolyl)urea (fluometuron), or (c) 1.12 to 8.96 kg/ha S-propyl butylethylthiocarbamate (pebulate). Herbicide toxicity to pine seedlings was in order of dichlobenil > fluometuron > pebulate. Acceptance of mild growth reduction would permit pebulate utilization in seed bed nurseries.
Canada Thistle Control on Roadsides
Authors: Foote L. E. , Kill D. L. , Williams C. S.
Published: June 2019

Canada thistle (Cirsium arvense (L.) Scop.) on roadsides was controlled by 4-amino-3,5,6-trichloropicolinic acid (picloram), (2,4-dichlorophenoxy)acetic acid (2,4-D), and (2,4,5-trichlorophenoxy)acetic acid (2,4,5-T), alone and in combination at various rates. There was no synergistic or additive effect, as determined by Canada thistle response, due to the addition of 2,4-D or 2,4,5-T to picloram. Control with ¾ lb/A picloram was not significantly less than that obtained with higher rates 1½ and 2 lb/A. Picloram reduced Canada thistle stands 80 to 100% and 2,4-D generally reduced the plant population 50% or less during the year of application and the year after. Late summer appeared to be an opportune time for spraying Canada thistle with ¾ to 1 lb/A picloram.
MSMA for Johnsongrass Control in Sugarcane
Authors: Millhollon Rex W.
Published: June 2019

Two overhead applications of monosodium methanearsonate (MSMA) at either 4 + 4 or 4 + 2.5 lb/A were required for effective postemergence control of rhizome johnsongrass (Sorghum halepense(L.) Pers.) in ratoon sugarcane (hybrids of the genusSaccharum). Two applications of MSMA in the spring controlled 95% of the johnsongrass, whereas two applications of 2,2-dichloropropionic acid (dalapon) at 4.5 lb/A, the standard treatment, controlled only 70%. In heavily infested fields, sugarcane treated with MSMA also outyielded sugarcane treated with dalapon. Sugarcane tolerated MSMA applied before June; the yield of weed-free sugarcane treated with MSMA was not significantly less than that of the untreated control. However, most MSMA treatments, particularly those applied in late spring, caused temporary leaf chlorosis and stunting. Sugarcane sprayed with MSMA before June generally contained no more arsenic in the juice and bagasse at harvest than untreated sugarcane. Application of MSMA in June or August increased the arsenic content, and resulted in concentrations up to 0.45 ppm in juice, and up to 1.68 ppm in bagasse.
Studies of Achene Dormancy in Fumitory
Authors: Jeffery Larry S. , Nalewaja John D.
Published: June 2019

Fumitory (Fumaria officinalis L.) achenes were subjected to various treatments to induce germination and to study dormancy. Complete pericarp removal, partial seed coat removal, puncturing the seed coat, heat treatment, red and far-red light treatments, and germination temperature treatments did not break dormancy. Low-temperature after-ripening for 60 days at 4 C dormant fumitory achenes resulted in 90 to 95% germination. Water leaching of fumitory achenes increased the time required for successful after-ripening and the water leachate stimulated Avena coleoptile cylinder elongation. Wild oat (Avena fatua L.) embryo germination was inhibited by high concentrations of fumitory achene leachate and stimulated slightly by lower concentrations. High concentrations of the leachate inhibited epicotyl and radicle growth of pre-sprouted lettuce (Lactuca sativa L.) seedlings and lower concentrations markedly stimulated radicle growth.
Influence of Pyrazon and Dalapon on the Seasonal Growth of Sugarbeets
Authors: Schweizer E. E.
Published: June 2019

Mixtures of 5-amino-4-chloro-2-phenyl-3(2H)-pyridazinone (pyrazon) plus 2,2-dichloropropionic acid (dalapon) were applied to sugarbeets (Beta vulgarisL.) at three growth stages 1 year and six growth stages another year. The growth of tops and roots was retarded most when sugarbeets were treated in the two-leaf stage of growth. The weight of tops and roots was reduced 43 and 50%, respectively, 6 weeks following an application of a mixture of 3 lb/A each of pyrazon and dalapon. However, when these sugarbeets were sampled 2 weeks later, the tops and roots weighed only 4 and 12% less, respectively, than the untreated controls. Furthermore, the early suppression in the growth of sugarbeets for 3 to 8 weeks following herbicide treatment had no effect on final yield of roots, pounds of sucrose, or sucrose content at harvest.
Some Effects of Humidity on the Translocation of 2,4,5-T in Bean Plants
Authors: Basler Eddie , Slife Fred W. , Long John W.
Published: June 2019

The effect of humidity on the rate and direction of translocation of stem-injected (2,4,5-trichlorophenoxy)acetic acid (2,4,5-T) in bean (Phaseolus vulgaris L., var. Stringless Green-pod) seedlings was determined. A total of 0.75 μg of 14C-labeled 2,4,5-T was injected into the stem with a 1-μl syringe pipette. Translocation was determined by assaying the nutrient solution and plant parts for 14C. High relative humidities enhanced downward translocation to roots and nutrient solutions. About 41% of the applied 2,4,5-T was found in the nutrient solution after 2 days' treatment at about 95% relative humidity while only 23% was found when treatment was conducted at 20% relative humidity. Low humidity during treatment caused much more 2,4,5-T to be translocated upward to the primary leaves and young shoots of the seedlings and this effect was more pronounced in plants which were grown in low humidity prior to treatment. The results confirm the conclusions of others and show that the increased basipetal phloem transport of herbicides in plants under high humidity is not due to an effect on penetration of herbicides in leaf tissue.
Tolerance of Sorghum to Postemergence Applications of Atrazine
Authors: Chamberlain E. W. , Becton A. J. , LeBaron H. M.
Published: June 2019

Grain sorghum (Sorghum bicolor(L.) Moench, var. RS-610) grown under field conditions during 1965 to 1967 on three soils in the High Plains of west Texas, was treated at different stages of plant growth with 2-chloro-4-(ethylamino)-6-(isopropylamino)s-triazine (atrazine). Maximum injury was caused by supplemental sprinkler irrigation. Tolerance of grain sorghum to atrazine increased as height of sorghum plants increased. Treatments on 1 and 3-inch sorghum reduced grain yields significantly, but plants treated when 6 inches or more in height produced yields similar to hand-weeded plots, except on Brownfield loamy sand where yields were reduced even at ½ lb/A. Similar trends were observed in 1966 with a forage sorghum (Lindsey 101F). However, yield reductions occurred only when atrazine was applied at 2 and 4 lb/A to sorghum plants I inch tall. Results show that atrazine can be used effectively and safely for weed control in sorghum grown on fine sandy loam or heavier soils in the southern High Plains, providing the crop is at least 6 inches tall when treated.
Effects of 3,5-dibromo-4-hydroxybenzaldehydeO-(2,4-dinitrophenyl)oxime on Reactions of Mitochondria and Chloroplasts
Authors: Moreland D. E. , Blackmon W. J.
Published: June 2019

The effects of 3,5-dibromo-4-hydroxybenzaldehydeO-(2,4-dinitrophenyl)oxime (hereinafter referred to as C-9122), 3,5-dibromo-4-hydroxybenzonitrile (bromoxynil), 3,5-dibromo-4-hydroxybenzaldoxime (hereinafter referred to as bromoxime), and 2,4-dinitrophenol (hereinafter referred to as DNP) on phosphorylation and electron transport were measured in mitochondria isolated from white potato tubers (Solarium tuberosumL.) and in chloroplasts from spinach leaves (Spinacia oleraceaL.). Mitochondrial oxygen utilization was monitored polarographically. All four chemicals stimulated ADP-limited oxygen utilization, inhibited non-ADP-limited oxygen uptake, and relieved oligomycin-inhibited oxygen uptake. C-9122 produced responses at lower molar concentrations than did bromoxynil, bromoxime, and DNP. The I50value for inhibition of state 3 respiration by C-9122 was 2.7 × 10−6M.

In chloroplasts, C-9122, bromoxime, and DNP inhibited photoreduction and coupled photophosphorylation with water as the electron donor, and with ferricyanide and NADP as electron acceptors. Cyclic photophosphorylation, with phenazine methosulfate as the electron mediator under an argon gas phase, also was inhibited. With ascorbate-2,6-dichlorophenolindophenol (hereinafter referred to as DPIP) as the electron donor, phosphorylation coupled to NADP reduction was inhibited, but not the reduction of NADP. C-9122 was the strongest inhibitor, and bromoxime was the weakest inhibitor of the several reactions. The I50value for inhibition of the coupled ferricyanide reduction was 4.6 × 10−6M for C-9122. C-9122 appeared to act in two different ways by (a) inhibiting electron transport at or near photosystem II and the oxygen evolution pathway, and (b) interfering with energy transfer and the generation of ATP. Bromoxynil inhibited photoreduction and photophosphorylation reactions in which water served as the electron donor; but it was a very poor inhibitor of both cyclic photophosphorylation, and photophosphorylation coupled to NADP reduction with ascorbate-DPIP serving as the electron donor. Because of the pivotal role of ATP in cellular metabolism, it is conceivable that interference with ATP generation could be a major (but not necessarily the only) mechanism through which the herbicidal activity of C-9122 is expressed.
Les changements de climat à l'époque préhistorique.
Authors: Galy G.-R.
Published: June 2019

L'ouvrage de M. RAIKES suscitera des critiques, mais ne laissera pas le lecteur indifférent. Regrettons seulement qu'il nous faille attendre la page 107 pour connaître les intentions de l'auteur, qui, jusqu'alors, attaque sans contrepartie certaines données des disciplines du quaternaire, en palynologie notamment.

Disons tout de suite que la pensée de l'auteur trouve des limites dans la formation scientifique de ce dernier : c'est un hydrologue, et un technicien qui, sur les divers domaines du quaternaire, s'en tient à la bibliographie en langue anglaise.
Effects of Light Component and Water Stress on Photosynthesis of Amazon Rainforests During the 2015/2016 El Niño Drought
Authors: Yan Hao , Wang Shao‐qiang , Huete Alfredo , Shugart Herman H.
Published: June 2019

Whether enhanced sunshine increases photosynthesis in Amazon rainforests during drought is unclear. Here we used a light component‐based two‐leaf‐photosynthesis model, driven with climate data and satellite vegetation data, to inspect the controlling mechanisms among climate factors on gross primary production (GPP) during the 2015/2016 El Niño drought event. We found that simulated GPP and Moderate Resolution Imaging Spectroradiometer enhanced vegetation index indicated an Amazonian “browning” and not a “green up” during the 2015/2016 El Niño year relative to the 2011–2014 interval. The result shows that, along with intensified sunlight, diffuse sunlight and diffuse fraction as well as canopy light use efficiency decreased, which further produced a decreased potential GPP* (determined by light components and leaf area index of shaded and sunlit leaves). The decreased GPP* and drought‐induced water stress jointly reduced canopy photosynthesis of Amazon rainforests during the 2015/2016 drought. The light component variations caused a reduction in GPP but with a magnitude inferior to the GPP reduction from water stress. These findings suggest that intensified sunlight did not enhance photosynthesis of Amazon rainforests and highlight the important role of light components in interannual and seasonal variations of photosynthesis in Amazon rainforests.
Sea Ice Control on Winter Subsurface Temperatures of the North Iceland Shelf During the Little Ice Age: A TEX86 Calibration Case Study
Authors: Harning David J. , Andrews John T. , Belt Simon T. , Cabedo‐Sanz Patricia , Geirsdóttir Áslaug , Dildar Nadia , Miller Gifford H. , Sepúlveda Julio
Published: June 2019

Holocene paleoceanographic reconstructions along the North Iceland Shelf have employed a variety of sea surface temperature and sea ice proxies. However, these surface proxies tend to have a seasonal bias toward spring/summer and thus only provide a discrete snapshot of surface conditions during one season. Furthermore, sea surface temperature proxies can be influenced by additional confounding variables resulting in markedly different Holocene temperature reconstructions. Here, we expand Iceland's marine paleoclimate toolkit with TEX86L: a temperature proxy based on the distribution of archaeal glycerol dibiphytanyl glycerol tetraether (GDGT) lipids. We develop a local Icelandic calibration from 21 surface sediment samples covering a wide environmental gradient across Iceland's insular shelves. Locally calibrated GDGT results demonstrate that (1) TEX86L reflects winter subsurface (0–200 m) temperatures on the North Iceland Shelf and (2) our calibration produces more realistic temperature estimates with substantially lower uncertainty (S.E. ±4 °C) over global calibrations. We then apply this new calibration to a high‐resolution marine sediment core (last millennium) collected from the central NIS with age control constrained by 14C‐dated mollusks. To test the veracity of the GDGT subsurface temperatures, we analyze quartz and calcite wt% and a series of highly branched isoprenoid alkenes, including the sea ice biomarker IP25, from the same core. The sediment records demonstrate that the development of thick sea ice during the Little Ice Age warmed the subsurface due to winter insulation. Importantly, this observation reflects a seasonal component of the sea ice/ocean feedback to be considered for the nonlinear cooling of the Little Ice Age in and around Iceland.
Data Mining Reveals the Dynamics of Auroral Substorms
Authors: Zastrow Mark
Published: June 2019

An analysis of 5 decades of satellite data has pieced together the most comprehensive picture yet of substorms, the magnetic disturbances that cause surges of aurora.
The Effect of Coral Bleaching Events in the Great Barrier Reef
Authors: Shultz David
Published: June 2019

A new study using seawater chemistry compares the status of the iconic reef before and after a bleaching event.
Diel and Seasonal Dynamics of Ecosystem‐Scale Methane Flux and Their Determinants in an Alpine Meadow
Authors: Chen Weinan , Zhang Fangyue , Wang Bingxue , Wang Jinsong , Tian Dashuan , Han Guangxuan , Wen Xuefa , Yu Guirui , Niu Shuli
Published: June 2019

Temporal variations of methane flux (FCH4) and its underlying mechanisms still remain poorly understood. To quantify diurnal and seasonal patterns of FCH4 and investigate its determinants, we monitored FCH4 using eddy covariance in an alpine meadow on the Qinghai‐Tibetan Plateau, China, from June 2015 to December 2016. As a strong CH4 sink, the alpine meadow on the Qinghai‐Tibetan Plateau consumed 0.41 ± 0.04 Tg CH4/year. There was an obvious diurnal pattern with more CH4 uptakes during the nighttime than the daytime for both growing and nongrowing season. The diurnal FCH4 during the growing and nongrowing season were positively correlated with air temperature (Ta), volumetric water content, friction velocity (u*), and vapor pressure deficit. The growing season FCH4 showed a significant quadratic polynomial relationship with the canopy conductance (Gw) and gross primary production). FCH4 was significantly higher in the growing season than in the nongrowing season. The seasonal FCH4 was negatively correlated with soil temperature and net radiation (Rn) but not with volumetric water content and gross primary production. Ridge regression models indicated that Ta and u* explained 83% of the variation in the diel dynamics of FCH4 during the growing season and explained 72% of the variation during the nongrowing season. Rn accounted for 49% of variations of FCH4 at the seasonal scale. The temporal patterns and the environmental controlling factors revealed in this study may improve model parameterization for biosphere‐atmosphere CH4 exchange simulation as well as the methane budget estimation.
Organic Matter and Mineral Interactions Modulate Flocculation Across Arctic River Mixing Zones
Authors: Lasareva Elena V. , Parfenova Aksana M. , Romankevich Evgeniy A. , Lobus Nikolay V. , Drozdova Anastasia N.
Published: June 2019

The focus of this study is organic matter changes and suspended particle and colloid behavior in riverine and marine water mixing zones. Laboratory experiments demonstrated that salinity, clay mineral type, and the nature of dissolved organic matter (DOM) have a strong influence on mineral suspension stabilities (clays, carbonates, and ferric hydroxide), which represent the main fractions of particulate and colloidal matter riverine export. Clay mineral modification by humic acids stabilizes suspensions under increasing salinity, resulting in greater export of particles to coastal zones. Simultaneously, modified particles are more efficiently aggregated by a flocculant than nonmodified particles. Field investigations were conducted in Arctic river mixing zones, providing new information about colloid matter and colloid organic carbon distributions in the mixing zones, which agreed well with laboratory studies. The ratio between colloid organic carbon and suspended matter may prove a useful criterion to distinguish effective flocculation zones. Arctic River DOM fluorescence suggests dominance of terrigenous humic substances in mixing zones as well as coprecipitation by coagulation and flocculation. Our findings may reconcile reports of nonconservative behavior of DOM previously reported in the mixing zone at salinities of less than 12. We suggest that there is a flocculation mechanism in the estuarine mixing zone, which implies the presence of natural active substances, released during microorganism viral lysis (viral shunting).
Double perovskite A2LaNbO6:Mn4+,Eu3+ (A = Ba, Ca) phosphors: potential applications in optical temperature sensing
Authors: Wang Peng , Mao Jiashan , Zhao Lu , Jiang Bin , Xie Chunyan , Lin Yan , Chi Fengfeng , Yin Min , Chen Yonghu
Published: June 2019

The study of the luminescence properties of Mn-doped double perovskite phosphors shows that they have potential applications in optical temperature sensing.
Order–disorder transition in nano-rutile TiO2 anodes: a high capacity low-volume change Li-ion battery material
Authors: Christensen Christian Kolle , Mamakhel Mohammad Aref Hasen , Balakrishna Ananya Renuka , Iversen Bo Brummerstedt , Chiang Yet-Ming , Ravnsbæk Dorthe Bomholdt
Published: June 2019

Li-Intercalation in nano-rutile TiO2-anodes induces loss of long-range order with the formation of ∼5 nm layered LixTiO2 domains with ∼1 nm columbite-like grain boundaries.
Prussian blue analogue-derived Ni and Co bimetallic oxide nanoplate arrays block-built from porous and hollow nanocubes for the efficient oxygen evolution reaction
Authors: Shen Yan , Guo Shu-Guang , Du Feng , Yuan Xiao-Bo , Zhang Yintong , Hu Jianqiang , Shen Qing , Luo Wenjun , Alsaedi Ahmed , Hayat Tasawar , Wen Guihua , Li Guo-Ling , Zhou Yong , Zou Zhigang
Published: June 2019

NixCo3–xO4 nanoplate arrays built from nanocubes were obtained, showing excellent activity towards OER.
Modeling the assembly of oppositely charged lock- and key-colloids
Authors: Stenqvist Björn , Trulsson Martin , Crassous Jérôme J.
Published: June 2019

Specific self-assembly of oppositely charged lock- and key-particles into well-defined colloidal molecules.
A Janus evaporator with low tortuosity for long-term solar desalination
Authors: Hu Rong , Zhang Junqi , Kuang Yudi , Wang Kebing , Cai Xiaoying , Fang Zhiqiang , Huang Wenqi , Chen Gang , Wang Zhongxing
Published: June 2019

A Janus evaporator with a low-tortuosity pore structure is reported for water generation from highly salty water. The unique pore structure together with the asymmetric wettability enables the evaporator to float on water with excellent salt excretion properties and heat localization, resulting in stable steam generation.
Structure- and porosity-tunable, thermally reactive metal organic frameworks for high-performance Ni-rich layered oxide cathode materials with multi-scale pores
Authors: Park Jun-Ho , Park Kwangjin , Han Dongwook , Yeon Dong-Hee , Jung Heechul , Choi Byungjin , Park Seong Yong , Ahn Sung-Jin , Park Jin-Hwan , Han Heung Nam , Lee Kang Hee
Published: June 2019

We describe for the first time molecular rearrangements in a highly stable and porous Ni-rich layered oxide cathode material (LiNi0.80Co0.15Mn0.05O2, Ni-rich NCM) using a thermally reactive, Co-embedded metal–organic framework (MOF).
15H-Diindolo[2,3-b:1′,2′,3′-lm]carbazole: a novel rigid donor for highly efficient thermally activated delayed fluorescence emitters
Authors: Konidena Rajendra Kumar , Lee Kyung Hyung , Lee Jun Yeob , Hong Wan Pyo
Published: June 2019

A novel rigid and strong 15H-diindolo[2,3-b:1′,2′,3′-lm]carbazole (DICz) donor was developed for efficient green thermally activated delayed fluorescence emitters and demonstrated promising device performance with EQE exceeding 20%.
Analogue bandwidth mismatch compensation techniques for time‐interleaved ADCs using FD‐SOI technology
Authors: Mas A. , Andre E. , Lelandais‐Perrault C. , Vinci dos Santos F. , Benabes P.
Published: June 2019

This study suggests several analogue bandwidth mismatch compensation techniques for time‐interleaved analogue‐to‐digital converters. All the techniques adjust the equivalent on‐resistance of the track and hold (T/H) under calibration. Simulations of a two‐channel time interleaved T/H running at GHz shows the effectiveness of the proposed compensations.
Uplink multi‐carrier multiple access scheme LDS‐IOTA
Authors: Wen Lei , Razavi Razieh , Lei Jing , Lai Ke , Zhong Jie
Published: June 2019

In this study, a multiple access scheme called low density signature isotropic orthogonal transfer algorithm (LDS‐IOTA) is proposed for overloading transmissions, and an analytical model for the performance limitations of this system is developed. LDS‐IOTA utilises a low density signature structure for spreading the symbols in frequency domain, and applies such technique to IOTA‐based filter bank multicarrier system. The input–output mutual information of LDS‐IOTA is analysed for the case of finite size modulation, and LDS‐IOTA is compared with OFDM as well as LDS‐OFDM over multipath fadding channels.
Performance analysis of MIMO AF CDMA hybrid satellite‐terrestrial cooperative networks using multiple relays strategy for downlink
Authors: Swalem Abdelrahman H. Gaber , Halim Joseph Victor Maher , Elhennawy Hadia
Published: June 2019

This study investigates dual‐hop fixed amplify‐and‐forward relaying performance analysis utilizing cooperative code division multiple‐access (CDMA) systems for hybrid satellite terrestrial cooperative networks (HSTCNs). The system performance is evaluated over independent non‐identical (i.n.i.) shadowed‐Rician fading channels for the links of the satellite‐terrestrial base station relays and the satellite‐mobile user link. However, Nakagami‐m fading channel is considered for the terrestrial base station relay‐mobile destination link. In this study, the main contribution is to implement multiple‐input multiple‐output (MIMO) configuration is applied on the CDMA HSTCNs, where the overall system performance is studied under different MIMO configurations at the source, relay and destination nodes. The spatial diversity of the multiple antennas is provided by employing the maximum ratio combining scheme. The study examines also the system performance under various numbers of cooperative relays as well as using both orthogonal and non‐orthogonal codes between the users. A novel closed expression for the moment generating function of the total end‐to‐end signal‐to‐noise ratio for three different transmission strategies. This is to calculate the outage probability, probability of error and the ergodic capacity. Moreover, the analytical and Monte‐Carlo simulation results are developed for different transmission techniques to show the improvement in the performance of the proposed HSTCNs.
High‐throughput Bit Flipping decoder for structured LDPC codes
Authors: Kalipatnapu Shantharam , Chakrabarti Indrajit
Published: June 2019

Low‐density parity‐check (LDPC) codes are predominantly used in many energy scavenging devices, data centres, and communication devices. In this work, the authors propose a high‐throughput parallel bit‐flipping (BF) decoder using multithreshold BF algorithm. The decoder is endowed with features including low interconnect complexity, simpler computations, and high throughput. The decoder has been synthesised in 65 nm technology for (273, 191) and (1023, 781) finite‐geometry LDPC (FG‐LDPC) codes. These decoders require an area of 0.1 and 0.45 mm2, and they achieve an average throughput of 147.57 and 268.5 Gbps and energy efficiency of 0.92 and 0.91 pJ/bit for (273, 191) and (1023, 781) FG‐LDPC codes, respectively. Compared to the state‐of‐the‐art design, the proposed designs offer 4.5 times higher normalised throughput.
Efficient gradient‐based dictionary optimisation method for time‐varying array incorporating with structure characteristic
Authors: Shen Jiajun , Zhou Tian , Xu Chao , Peng Dongdong , Zhang Wanyuan
Published: June 2019

To guarantee good sparsity reconstruction quality, a suitable dictionary should be as orthogonal as possible. Also, to reduce the coherence of a dictionary, a sensing matrix optimisation model should be formulated. In this model, a high‐dimension O(N) problem has to be considered because the sparse representation base is overcompleted, thus leading to a heavy computational load. This study proposes an efficient gradient‐based method to address the dictionary optimisation problem of the time‐varying arrays, whose elements relatively move in an arbitrary but known way. The dictionary optimisation models associated with different array geometries are formulated with distinct structure characteristic, and the Toeplitz and circulant properties are incorporated into the corresponding models to reduce the complexity by dimension reduction from O(N) to O(2) and O(1), respectively. An alternating minimisation approach for sensing matrix design (SMD) is derived by the gradient descent method, and an adaptive stepsize selection method is derived to further reduce complexity. Numerous simulations are conducted, and simulation results demonstrate that the presented methods have lower computational complexity but similar sparse recovery performance as the normalisation‐constrained SMD method. Also, the effectiveness of the proposed structured optimisation framework to design a sensing matrix of a time‐varying array is verified.
Block‐sparse representation of radar scattering centres for land‐based vehicles
Authors: Wang Xuan
Published: June 2019

The scattering centre model is well known as an approximation to provide a sparse abstraction ofcomplex targets in radar applications. On the basis of the block‐sparsity andhigh‐frequency approximations, an improved scattering centre representationscheme is proposed for different angular observations of the land‐basedvehicles. For good insights into target physics and feature stability, theland‐based vehicle is observed by airborne radar system in separate observationsections according to independent aspect angle regions. On the basis of that,the image patch of the land‐based vehicle can be reconstructed with themeasurements in each observation section. To reduce redundant information,compressive sensing followed by the CLEAN algorithm is exploited to extract thescattering centres from each image patch separately. Thus, the predominantscattering centres of the land‐based vehicle can be grouped into severalsub‐structures with respect to the image patches. Numerical simulations are usedto verify the validity and efficiency of the block‐sparse representation (SR)scheme. The block‐sparse representation scheme can be implemented with lowcomputational complexity and flexibly extended to further research with multipletargets representation and applications in the radar field.
GMTI STAP performance under space‐time impaired clutter environment
Authors: Bhamre Pooja , Gupta Shilpi
Published: June 2019

Ground moving target indicator (GMTI) RADAR system frequently incorporates space‐time adaptive processing for successful moving targets discrimination in a highly cluttered environment. The minimum detectable velocity (MDV) of the target gets affected due to the added clutter impairments such as foliage penetration and angle independent channel mismatch. A novel clutter model is postulated in this work that includes assessment enacted in view of both angle and Doppler clutter impairments at a time instead of their individual analysis as in the reported literature. The performance of the GMTI RADAR in terms of the signal‐to‐interference‐plus‐noise ratio loss is evaluated using the extrusive beamforming methods namely sample matrix inversion and principal component canceller. In high decorrelated clutter environment, the later outperforms in terms of the MDV, making use of a lesser number of training snapshots. The approach is validated with mathematical modelling and numerical simulations.
Measuring dielectric properties by two methods using software‐defined radio
Authors: Lourenço Chuma Euclides , Iano Yuzo , Roger Leonardo Lorenzo Bravo , Fontgalland Glauco
Published: June 2019

Two methods for measuring the dielectric constant and loss tangent of the dielectric materials using software‐defined radio (SDR) are presented, which may be used as an alternative to the expensive vector network analysers (VNA). The first method used was the cylindrical cavity resonator designed for a resonance frequency of 2.5 GHz. The second method used was the complementary split ring resonator designed for a resonance frequency of 1.25 GHz. In both cases, measurements were carried out using VNA and SDR to compare the efficiency of both tools. The measurement accuracy was assessed by comparing the results with the declared values in the data sheets of dielectric manufacturers. The results showed a good agreement with the available data sheet values and further demonstrated that the SDR is an excellent tool for microwave measurements.
Performance analysis of vegetable oil‐based nanofluids used in transformers
Authors: Baruah Niharika , Maharana Mrutyunjay , Nayak Sisir Kumar
Published: June 2019

Nanofluids (NFs) are an emerging technology in the field of dielectrics. These oils are used in transformers and other power apparatus for the purpose of insulation and cooling. The vegetable oil (VO) proposed in this study is the Pongamia pinnata oil (PPO), commonly known as karanji oil. The molecular structure of PPO is changed by the transesterification process and converted to Pongamia oil methyl ester (POME) as the crude oil is not suitable for direct use because of its high viscosity, high pour point, and acid number. For preparing the NF, 0.01 wt.% of exfoliated hexagonal boron nitride (Eh‐BN) is dispersed in mineral oil (MO) and POME to prepare MO‐based NF (MO‐NF) and POME‐based NF (POME‐NF), respectively. This study explores the various thermophysical and electrical properties of four types of oils – MO, MO‐NF, POME, and POME‐NF. Thermophysical properties such as thermal conductivity, interfacial tension, flash point, and pour point, and electrical properties such as dielectric constant, dielectric dissipation factor, and dielectric strength are measured and a comparative analysis is carried out among all the four types of oils. The charging dynamics study has also been investigated to understand the phenomenon underlying the enhanced breakdown voltages of VO‐based NFs.
A metamaterial solves an integral equation
Authors: Middleton Christine
Published: June 2019

By iteratively processing an optical signal, the structure functions as an analog computer.
Spontaneous generation of internal waves
Authors: Shakespeare Callum J.
Published: June 2019

The waves responsible for transporting energy in the ocean and atmosphere are not solely a product of the combined forces of winds, tides, and mountains.
Obscure waves in planetary atmospheres
Authors: Yiğit Erdal , Medvedev Alexander S.
Published: June 2019

On Earth and on other planets, internal gravity waves shape the dynamics and thermodynamics of the atmosphere.
Putting the squeeze on axions
Authors: van Bibber Karl , Lehnert Konrad , Chou Aaron
Published: June 2019

Microwave cavity experiments make a quantum leap in the search for the dark matter of the universe.
Indestructible plasma optics
Authors: Milchberg Howard
Published: June 2019

Working with ultra-intense laser pulses? These optical elements are what you need.
Protein phosphatase 2A has an essential role in promoting thymocyte survival during selection
Authors: Zheng Mingzhu , Li Dan , Zhao Zhishan , Shytikov Dmytro , Xu Qin , Jin Xuexiao , Liang Jingjing , Lou Jun , Wu Songquan , Wang Lie , Hu Hu , Zhou Yiting , Gao Xiang , Lu Linrong
Published: June 2019

Significance

Ser/Thr phosphorylation is critical for T cell receptor signal transduction as well as cell survival/death regulation in developing thymocytes. In this work, we established a Ser/Thr phosphorylation profile during thymocytes selection. Substrate analysis revealed PP2A as the most important enzyme responsible for the dephosphorylation events, which was proved in the PP2A cKO model. Thymic-specific depletion of PP2A caused impaired thymocyte selection. The decrease of DP thymocytes upon PP2A cKO is accompanied by dysregulated dephosphorylation of apoptosis-related proteins and increased cell apoptosis, which could be rescued by Bcl2 transgene or p53 knockout. This studies the role of PP2A in thymocyte development and provides insights to understand T cell development through dephosphorylation regulation of apoptosis-related molecules.
Intracellular iron deficiency in pulmonary arterial smooth muscle cells induces pulmonary arterial hypertension in mice
Authors: Lakhal-Littleton Samira , Crosby Alexi , Frise Matthew C. , Mohammad Goran , Carr Carolyn A. , Loick Paul A. M. , Robbins Peter A.
Published: June 2019

Significance

Pulmonary arterial hypertension (PAH) is a disease in which lung blood pressure is raised chronically, causing right heart failure. It has been shown that iron deficiency also raises lung blood pressure. However, we don’t know the mechanisms because we don’t understand precisely how cells of the lung blood vessels are affected by iron levels. The smooth muscle cells of the lung blood vessels are important for controlling lung blood pressure. Our study shows that iron deficiency specifically within these cells is sufficient to cause PAH, even against a background of normal iron levels in other tissues.
Location deviations of DNA functional elements affected SNP mapping in the published databases and references
Authors: Zheng Hewei , Zhao Xueying , Wang Hong , Ding Yu , Lu Xiaoyan , Zhang Guosi , Yang Jiaxin , Wang Lianzong , Zhang Haotian , Bai Yu , Li Jing , Wu Jingqi , Jiang Yongshuai , Xu Liangde
Published: June 2019

The recent extensive application of next-generation sequencing has led to the rapid accumulation of multiple types of data for functional DNA elements. With the advent of precision medicine, the fine-mapping of risk loci based on these elements has become of paramount importance. In this study, we obtained the human reference genome (GRCh38) and the main DNA sequence elements, including protein-coding genes, miRNAs, lncRNAs and single nucleotide polymorphism flanking sequences, from different repositories. We then realigned these elements to identify their exact locations on the genome. Overall, 5%–20% of all sequence element locations deviated among databases, on the scale of kilobase-pair to megabase-pair. These deviations even affected the selection of genome-wide association study risk-associated genes. Our results implied that the location information for functional DNA elements may deviate among public databases. Researchers should take care when using cross-database sources and should perform pilot sequence alignments before element location-based studies.
Structural and environmental constraints on reduction of paired appendages among vertebrates
Authors: Macaluso Loredana , Carnevale Giorgio , Casu Raffaello , Pietrocola Daniel , Villa Andrea , Delfino Massimo
Published: June 2019

Burrowing habits or complex environments have generally been considered as potential drivers acting on reduction and loss of the appendicular skeleton among vertebrates. Herein, we suggest that this might be the case for lissamphibians and squamates, but that fin loss in fishes is usually prevented by important structural constraints, because pectoral fins are commonly used to control rolling and pitching. We provide an overview of the distribution of paired appendage reduction across vertebrates while examining the ecological affinities of finless and limbless clades. We analysed the correlation between lifestyle and fin or limb loss using the discrete comparative analysis. The resulting Bayesian factors indicate strong evidence of correlation between: (1) pectoral-fin loss and coexistence of anguilliform elongation and burrowing habits or complex habitat in teleost fishes; and (2) limb loss and a burrowing or grass-swimming lifestyle in squamate reptiles and lissamphibians. These correlations suggest that a complex environment or a fossorial habit is a driving force leading to appendage loss. The only style of locomotion that is functional even in the absence of paired appendages is the undulatory one, which is typical of all elongated reptiles and lissamphibians, but certainly less common in teleost fishes.
GRP78 antibodies damage the blood–brain barrier and relate to cerebellar degeneration in Lambert-Eaton myasthenic syndrome
Authors: Shimizu Fumitaka , Takeshita Yukio , Sano Yasuteru , Hamamoto Yuka , Shiraishi Hirokazu , Sato Takuya , Yoshimura Shunsuke , Maeda Toshihiko , Fujikawa Susumu , Nishihara Hideaki , Kitanosono Hiroko , Tsujino Akira , Motomura Masakatsu , Kanda Takashi
Published: June 2019

Lambert-Eaton myasthenic syndrome (LEMS) is an autoimmune disease of the neuromuscular junction caused by autoantibodies binding to P/Q-type voltage-gated calcium channels. Breakdown of the blood–brain barrier and diffusion of cerebellar granule/Purkinje cell-reactive autoantibodies into the CNS are critical for the pathogenesis of paraneoplastic cerebellar degeneration (PCD) with Lambert-Eaton myasthenic syndrome. We recently found evidence that glucose-regulated protein 78 (GRP78) autoantibodies in the plasma of patients with neuromyelitis optica promote the CNS access of AQP4 autoantibodies. In the present study, we investigated whether the GRP78 autoantibodies in PCD-LEMS IgG boost the brain uptake of cerebellar cell-reactive antibodies across the blood–brain barrier and facilitate cerebellar dysfunction. We first evaluated the effects of purified IgG from PCD-LEMS or PCD patients on the blood–brain barrier function in human brain microvascular endothelial cells using a high content imaging system with nuclear factor κB p65 and intracellular adhesion molecule 1 (ICAM1) immunostaining. Next, we identified GRP78 autoantibodies causing blood–brain barrier permeability in PCD-LEMS IgG by co-immunoprecipitation and the living cell-based antibody binding assays. Exposure of brain microvascular endothelial cells to IgG from PCD-LEMS patients induced nuclear factor κB p65 nuclear translocation, ICAM1 upregulation, reduced claudin-5 expression, increased permeability and increased autocrine IL-1β and IL-8 secretion; the IgG from patients with Lambert-Eaton myasthenic syndrome did not have these effects. We detected GRP78 autoantibodies in the IgG of LEMS-PCD (83.3%, n = 18), but observed fewer in patients with LEMS (6.6%, n = 15) and none were observed in the control subjects (n = 8). The depletion of GRP78 autoantibodies reduced the biological effect of LEMS-PCD IgG on brain microvascular endothelial cells. These findings suggest that GRP78 autoantibodies play a role beyond neuromyelitis optica and that they have direct implications in the phenotypic differences between PCD-LEMS and LEMS.
Sex-Dependent Associations among Maternal Depressive Symptoms, Child Reward Network, and Behaviors in Early Childhood
Authors: Wang Qiang , Zhang Han , Poh Joann S , Pecheva Diliana , Broekman Birit F P , Chong Yap-Seng , Shek Lynette P , Gluckman Peter D , Fortier Marielle V , Meaney Michael J , Qiu Anqi
Published: June 2019

Maternal depression is associated with disrupted neurodevelopment in offspring. This study examined relationships among postnatal maternal depressive symptoms, the functional reward network and behavioral problems in 4.5-year-old boys (57) and girls (65). We employed canonical correlation analysis to evaluate whether the resting-state functional connectivity within a reward network, identified through an activation likelihood estimation (ALE) meta-analysis of fMRI studies, was associated with postnatal maternal depressive symptoms and child behaviors. The functional reward network consisted of three subnetworks, that is, the mesolimbic, mesocortical, and amygdala–hippocampus reward subnetworks. Postnatal maternal depressive symptoms were associated with the functional connectivity of the mesocortical subnetwork with the mesolimbic and amygdala–hippocampus complex subnetworks in girls and with the functional connectivity within the mesocortical subnetwork in boys. The functional connectivity of the amygdala–hippocampus subnetwork with the mesocortical and mesolimbic subnetworks was associated with both internalizing and externalizing problems in girls, while in boys, the functional connectivity of the mesocortical subnetwork with the amygdala–hippocampus complex and the mesolimbic subnetworks was associated with the internalizing and externalizing problems, respectively. Our findings suggest that the functional reward network might be a promising neural phenotype for effects of maternal depression and potential intervention to nurture child behavioral development.