bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Sowing Dates and Flower Pruning on Chemical Properties and Shelf Life of Yam Bean (Pachyrrhizus erosus L.) Tubers
Authors: Shevale Priti P. , Gudadhe Pradnya S. , Sarangkar A. S. , Ghume O. G.
Published: October 2024

Underutilized crops provide essential micro-nutrient and thus able to complement staple foods. The inhibitory effect of floral and fruit development may affect the tuber development. It is logical to assume that large amounts of nitrogen and other essential components are assimilated by the reproductive parts of plant, hence it is important to remove these reproductive parts as well as time of sowing also affect the shelf life and chemical properties of yam bean tubers which form the basis of an experiment on effect of sowing dates and flower pruning on chemical properties and shelf life of Yam bean tubers. An experiment was conducted at Department of Vegetable Science, College of Horticulture, Dr. Balasaheb Sawant Konkan Krishi Vidyapeeth, Dapoli during the year 2023-24. Twelve treatments and 3 replications in Factorial Randomized Block Design Planting dates (D) i.e., D₁-1st week of June, D₂-3rd week of June, D3 -1st week of July, D4 -3rd week of July and Interval of reproductive pruning (P) i.e., P1 – Weekly, P2 – Fortnightly, P3 – No pruning. Chemical analysis of the tubers was done to analyse the starch, fiber, dry matter, TSS and shelf life of the tubers from various treatments. Investigation revealed that among the various chemical parameters and shelf life the effect of interaction on starch, fiber, dry matter and shelf life was significant whereas it was non-significant on TSS. The highest starch content was recorded in D3P1 (6.81%). The fiber content was analysed highest in D4P3 (0.69 %). The highest dry matter content was analysed in D1P3 (24.59 %). The highest TSS was recorded in D1P1 (6.40 °B) and highest shelf life was recorded in D1P1 (36.56 days). Considering its nutritional quality and sustainability in the region it can be an alternative crop with food security, nutritional security as well as economic sustainability [1].
Study on Interspecific Hybridization between Daincha (Sesbania aculeatea) and Related Species
Authors: S Chitra. , Thirumurugan.T  , A Subramanian , P Jeyaprakash
Published: October 2024

Wide hybridization can enrich crops' genetic background and diversity by comparing different species and integrating the different parental traits. In the present study, interspecific hybridization was performed between Daincha and two related sesbania species by hand emasculation and crossing technique. A total of 460 hybrids were obtained in the Sesbania aculeata X Sesbania bispinosa cross, but no hybrids were obtained in their reverse cross, indicating the same cross combination has a large difference in the reciprocal crosses and that the hybrid has certain unidirectionality. The hybrids looked more like their Sesbania aculeata parent in stem and leaf characteristics. A total of 570 hybrids were obtained in the cross Sesbania aculeata X Sesbania rostrata, while no hybrids were obtained by reverse cross combination. The hybrid showed intermediate morphological traits when compared to their parents. Developing hybrids and segregating populations are useful genetic resources and provide interspecific hybridization to enlarge the gene pool of Daincha species.
Determining Potential Groundwater Recharge Zones in the North Gujarat Region of Gujarat State Using Techniques of Geoinformatics and Multi-Criteria Decision Analysis
Authors: Baria S.V. , Rank H.D. , Limbasiya B.B. , Ghritesh Akansha , Satasiya R.M.
Published: October 2024

The rapid increase in population and industrialization has significantly raised the consumption of groundwater resources for domestic, agricultural, and industrial purposes. This study aims to develop groundwater recharge potential zone maps to assist in the construction of artificial recharge structures in the North Gujarat Region of Gujarat, India. An integrated approach of remote sensing (RS), geographical information system (GIS), and multi-criteria decision analysis (MCDA) were used to achieve this goal.  Influencing factors of groundwater availability included geology, soil, lineament density, slope, rainfall, land use/land cover, geomorphology, and drainage density, were analyzed to delineate potential groundwater recharge zones. each influencing parameter was determined by using Saaty's Analytic Hierarchy Process (AHP) method, and sub-parameters were ranked according to the AHP scale. A weighted overlay analysis tool in ArcGIS software was employed to map the groundwater recharge potential zones in the North Gujarat region. The classified results of the recharge potential area in the study area consist of excellent (9.93%), good (27.90%), moderate (17.58%), poor (3.92%), and very poor (0.92%) These findings provide valuable insights for effectively planning and managing groundwater resource development in the region.
Analysis of Socio-economic Variables Impacting Poverty Alleviation in Regional Development: A Case Study in Deli Serdang Regency, Indonesia
Authors: Nasution Maimunah , Lubis Satia Negara , Kesuma Sinar Indra
Published: October 2024

This study analyzes the impact of macro socio-economic variables on poverty alleviation within the context of regional development in North Sumatra Province from 2019 to 2023. The socio-economic variables examined include economic growth, average years of schooling, life expectancy, and the open unemployment rate. The research employs a panel data regression approach using the Fixed Effect Model, selected based on Chow and Hausman test results, to determine the best model fit. The findings reveal that economic growth, average years of schooling, and life expectancy have significant negative effects on poverty reduction, indicating that improvements in these areas help alleviate poverty. Conversely, the open unemployment rate shows a significant positive effect on poverty levels, suggesting that higher unemployment exacerbates poverty. The model explains 99% of the variation in poverty (R² = 0.990), indicating a high explanatory power. Based on these results, the study recommends the implementation of inclusive economic policies focusing on boosting economic growth, improving educational access, enhancing healthcare systems, and creating job opportunities to effectively reduce poverty. Additionally, further research with broader geographical coverage and more refined methods is necessary to enrich the understanding of poverty determinants in different regional contexts.
Öğretmenlerin Öz-yönetim ve Öz-kontrol ile Öz-liderlik Becerilerinin İncelenmesi
Authors: Ercoşkun Muhammet Hanifi , Erişmiş Fatih
Published: October 2024

Bu çalışmada, öğretmenlerin öz-yönetim ve öz-kontrol ile öz-liderlik becerileri arasındaki ilişkinin çeşitli değişkenler açısından incelenmesi amaçlanmıştır. Bu amaca en uygun yöntemin nicel araştırma yöntemlerinden betimsel tarama yöntemi olduğuna karar verilerek bu çalışma yürütülmüştür. Basit seçkisiz örnekleme yöntemi kullanılarak Türkiye’deki bir ilde ilkokul, ortaokul ve liselerde görev yapan 322 öğretmenden toplanan veriler kullanılmıştır. Veriler çoklu hiyerarşik regresyon analizi, t-testi ve ANOVA ile test edilmiştir. Araştırma sonucunda öz-yönetim ve öz-kontrol becerileri, öz-liderlik becerilerinin anlamlı bir yordayıcısı olduğu belirlenmiştir. Ayrıca öğretmenlerin yaşı ilerledikçe kendini ödüllendirme ve kendi kendine konuşma davranışlarını daha az sergiledikleri; erkeklerin kadınlara göre kendini daha fazla cezalandırdığı; bunun yanında kadınların ise kendini ödüllendirme, kendine hatırlatıcılar belirleme, doğal ödül stratejileri, kendi kendine konuşma ve öz-liderlik becerilerini erkeklere göre daha fazla kullandığı; başka fakültelerde lisansüstü eğitim yapanların eğitim fakültesinde lisansüstü eğitim yapan ve lisansüstü eğitim yapmayan öğretmenlere göre daha başarılı performans hayal etme becerisine sahip olduğu belirlenmiştir.
A structural sketch of RcdA, a transcription factor controlling the master regulator of biofilm formation
Authors: Sugino Hirotaka , Usui Takanori , Shimada Tomohiro , Nakano Masahiro , Ogasawara Hiroshi , Ishihama Akira , Hirata Akira
Published: June 2017

RcdA is a regulator of curlin subunit gene D, the master regulator of biofilm formation in Escherichia coli. Here, we determined the X‐ray structure of RcdA at 2.55 Å resolution. RcdA consists of an N‐terminal DNA‐binding domain (DBD) containing a helix‐turn‐helix (HTH) motif and a C‐terminal dimerization domain, and forms a homodimer in crystals. A computational docking model of the RcdA‐DNA complex allowed prediction of the candidate residues responsible for DNA binding. Our structure‐guided mutagenesis, in combination with gel shift assay, atomic force microscopic observation, and reporter assay, indicate that R32 in α2 of the HTH motif plays an essential role in the recognition and binding of target DNA while T46 in α3 influences the mode of oligomerization. These results provide insights into the DNA‐binding mode of RcdA.
The tropical precipitation pickup threshold and clouds in a radiative convective equilibrium model: 1. Column moisture
Authors: Igel Matthew R. , Herbener Stephen R. , Saleeby Stephen M.
Published: June 2017

A survey of published results indicates that a column relative humidity near 77% is consistently observed to separate raining and nonraining columns in a time and space mean in the tropics, but why this approximate value of humidity should initiate such a statistical state transition is not readily apparent. An investigation is conducted of the submesoscale cloud processes that link column relative humidity to this abrupt pickup in heavy precipitation and of the magnitude of humidity at which this transition occurs. A cloud system resolving model in radiative convective equilibrium is used. Precipitation statistics from this simulation indicate a switch in mean precipitation state at 77% relative humidity with infrequent heavy rainfall at lower humidity. These statistics are broadly insensitive to spatial scaling. Low‐level cloud fraction and convergent flux of moisture are shown to be sensitive to column humidity near 77%, while upper level cloud fraction is markedly less sensitive. Mean updraft mass flux increases with increasing humidity but only at values of humidity well above the pickup. Both warm rain processes and melting are shown to depend strongly on column humidity near the pickup but in different circumstances. No single process is determined to result in a pickup in precipitation. It is suggested that column humidity temporally leads precipitation and therefore causes its intensity.
Can energy fluxes be used to interpret glacial/interglacial precipitation changes in the tropics?
Authors: Roberts W. H. G. , Valdes P. J. , Singarayer J. S.
Published: June 2017

Recent theoretical advances in the relationship between heat transport and the position of the Intertropical Convergence Zone (ITCZ) present an elegant framework through which to interpret past changes in tropical precipitation patterns. Using a very large ensemble of climate model simulations, we investigate whether it is possible to use this framework to interpret changes in the position of the ITCZ in response to glacial and interglacial boundary conditions. We find that the centroid of tropical precipitation, which represents the evolution of precipitation in the whole tropics, is best correlated with heat transport changes. We find that the response of the annual mean ITCZ to glacial and interglacial boundary conditions is quite different to the response of the climatological annual cycle of the ITCZ to the seasonal cycle of insolation. We show that the reason for this is that while the Hadley Circulation plays a dominant role in transporting heat over the seasonal cycle, in the annual mean response to forcing, the Hadley Circulation is not dominant. When we look regionally, rather than at the zonal mean, we find that local precipitation is poorly related either to the zonal mean ITCZ or to meridional heat transport. We demonstrate that precipitation is spatially highly variable even when the zonal mean ITCZ is in the same location. This suggests only limited use for heat transport in explaining local precipitation records; thus, there is limited scope for using heat transport changes to explain individual paleoprecipitation records.
Long‐term monitoring of long‐period seismicity and space‐based SO2 observations at African lava lake volcanoes Nyiragongo and Nyamulagira (DR Congo)
Authors: Barrière Julien , Oth Adrien , Theys Nicolas , d'Oreye Nicolas , Kervyn François
Published: June 2017

Magma ascent that may lead to an eruption is commonly accompanied by variations of long‐period seismic activity and SO2 degassing. Space‐based measurements of SO2 emission rates represent a rapidly emerging and highly convenient approach for volcano monitoring; however, combining these long‐term remote sensing observations with seismic data is still rare and, in particular, the potential of such a multidisciplinary approach as volcano monitoring tool remains largely unexplored. Here shallow magmatic activity and magma migration patterns at the two closely located African volcanoes Nyiragongo and Nyamulagira are inferred from a nearly 3 years long SO2 emissions record and seismic observations between April 2014 and February 2017. The discrimination of magma movements into shallow plumbing systems allows for signs of volcanic unrest to be deciphered on a daily time scale, even with limited instrumentation on site.
Assessing the contribution of internal climate variability to anthropogenic changes in ice sheet volume
Authors: Tsai Chii‐Yun , Forest Chris E. , Pollard David
Published: June 2017

Understanding ice sheet response to different sources of uncertainty in projecting the climate is essential for assessing long‐term risk of sea level rise (SLR). The impact of uncertainty caused by internal climate variability (ICV) on future ice sheet changes has not been assessed explicitly. Here we estimate how ICV affects ice sheet projections using a three‐dimensional ice sheet model driven by climate fields from two large ensembles of climate model simulations differing in initial climate states. We find that ICV causes approximately 2 mm uncertainty in the estimated SLR due to Greenland ice sheet mass loss during 1992–2011, which is nearly double the observational uncertainty. Additionally, SLR differences due to ICV are about 17% of the mean total change of SLR in 2100. This study highlights a critical need to assess uncertainties of projecting ice sheet loss due to ICV to obtain robust estimates of both historical and future SLR.
Hiatus‐like decades in the absence of equatorial Pacific cooling and accelerated global ocean heat uptake
Authors: von Känel Lukas , Frölicher Thomas L. , Gruber Nicolas
Published: June 2017

A surface cooling pattern in the equatorial Pacific associated with a negative phase of the Interdecadal Pacific Oscillation is the leading hypothesis to explain the smaller rate of global warming during 1998–2012, with these cooler than normal conditions thought to have accelerated the oceanic heat uptake. Here using a 30‐member ensemble simulation of a global Earth system model, we show that in 10% of all simulated decades with a global cooling trend, the eastern equatorial Pacific actually warms. This implies that there is a 1 in 10 chance that decadal hiatus periods may occur without the equatorial Pacific being the dominant pacemaker. In addition, the global ocean heat uptake tends to slow down during hiatus decades implying a fundamentally different global climate feedback factor on decadal time scales than on centennial time scales and calling for caution inferring climate sensitivity from decadal‐scale variability.
Dependence of model‐simulated response to ozone depletion on stratospheric polar vortex climatology
Authors: Lin Pu , Paynter David , Polvani Lorenzo , Correa Gustavo J. P. , Ming Yi , Ramaswamy V.
Published: June 2017

We contrast the responses to ozone depletion in two climate models: Community Atmospheric Model version 3 (CAM3) and Geophysical Fuild Dynamics Laboratory (GFDL) AM3. Although both models are forced with identical ozone concentration changes, the stratospheric cooling simulated in CAM3 is 30% stronger than in AM3 in annual mean, and twice as strong in December. We find that this difference originates from the dynamical response to ozone depletion, and its strength can be linked to the timing of the climatological springtime polar vortex breakdown. This mechanism is further supported by a variant of the AM3 simulation in which the southern stratospheric zonal wind climatology is nudged to be CAM3‐like. Given that the delayed breakdown of the southern polar vortex is a common bias among many climate models, previous model‐based assessments of the forced responses to ozone depletion may have been somewhat overestimated.
Holocene black carbon in Antarctica paralleled Southern Hemisphere climate
Authors: Arienzo M. M. , McConnell J. R. , Murphy L. N. , Chellman N. , Das S. , Kipfstuhl S. , Mulvaney R.
Published: June 2017

Black carbon (BC) and other biomass‐burning (BB) aerosols are critical components of climate forcing, but quantification, predictive climate modeling, and policy decisions have been hampered by limited understanding of the climate drivers of BB and by the lack of long‐term records. Prior modeling studies suggested that increased Northern Hemisphere anthropogenic BC emissions increased recent temperatures and regional precipitation, including a northward shift in the Intertropical Convergence Zone (ITCZ). Two Antarctic ice cores were analyzed for BC, and the longest record shows that the highest BC deposition during the Holocene occurred ~8–6 k years before present in a period of relatively high austral burning season and low growing season insolation. Atmospheric transport modeling suggests South America (SA) as the dominant source of modern Antarctic BC and, consistent with the ice core record, climate model experiments using mid‐Holocene and preindustrial insolation simulate comparable increases in carbon loss due to fires in SA during the mid‐Holocene. SA climate proxies document a northward shifted ITCZ and weakened SA Summer Monsoon (SASM) during this period, with associated impacts on hydroclimate and burning. A second Antarctic ice core spanning the last 2.5 k years documents similar linkages between hydroclimate and BC, with the lowest deposition during the Little Ice Age characterized by a southerly shifted ITCZ and strengthened SASM. These new results indicate that insolation‐driven changes in SA hydroclimate and BB, likely linked to the position of the ITCZ, modulated Antarctic BC deposition during most of the Holocene and suggests connections and feedbacks between future BC emissions and hydroclimate.
High‐Efficiency Solution‐Processed Inorganic Metal Halide Perovskite Light‐Emitting Diodes
Authors: Cho Himchan , Wolf Christoph , Kim Joo Sung , Yun Hyung Joong , Bae Jong Seong , Kim Hobeom , Heo Jung‐Min , Ahn Soyeong , Lee Tae‐Woo
Published: June 2017

This paper reports highly bright and efficient CsPbBr3 perovskite light‐emitting diodes (PeLEDs) fabricated by simple one‐step spin‐coating of uniform CsPbBr3 polycrystalline layers on a self‐organized buffer hole injection layer and stoichiometry‐controlled CsPbBr3 precursor solutions with an optimized concentration. The PeLEDs have maximum current efficiency of 5.39 cd A−1 and maximum luminance of 13752 cd m−2. This paper also investigates the origin of current hysteresis, which can be ascribed to migration of Br− anions. Temperature dependence of the electroluminescence (EL) spectrum is measured and the origins of decreased spectrum area, spectral blue‐shift, and linewidth broadening are analyzed systematically with the activation energies, and are related with Br− anion migration, thermal dissociation of excitons, thermal expansion, and electron–phonon interaction. This work provides simple ways to improve the efficiency and brightness of all‐inorganic polycrystalline PeLEDs and improves understanding of temperature‐dependent ion migration and EL properties in inorganic PeLEDs.
Fused Hexacyclic Nonfullerene Acceptor with Strong Near‐Infrared Absorption for Semitransparent Organic Solar Cells with 9.77% Efficiency
Authors: Wang Wei , Yan Cenqi , Lau Tsz‐Ki , Wang Jiayu , Liu Kuan , Fan Yan , Lu Xinhui , Zhan Xiaowei
Published: June 2017

A fused hexacyclic electron acceptor, IHIC, based on strong electron‐donating group dithienocyclopentathieno[3,2‐b]thiophene flanked by strong electron‐withdrawing group 1,1‐dicyanomethylene‐3‐indanone, is designed, synthesized, and applied in semitransparent organic solar cells (ST‐OSCs). IHIC exhibits strong near‐infrared absorption with extinction coefficients of up to 1.6 × 105m−1 cm−1, a narrow optical bandgap of 1.38 eV, and a high electron mobility of 2.4 × 10−3 cm2 V−1 s−1. The ST‐OSCs based on blends of a narrow‐bandgap polymer donor PTB7‐Th and narrow‐bandgap IHIC acceptor exhibit a champion power conversion efficiency of 9.77% with an average visible transmittance of 36% and excellent device stability; this efficiency is much higher than any single‐junction and tandem ST‐OSCs reported in the literature.
Bis(dibenzylideneacetone)palladium(0)/tert‐Butyl Nitrite‐ Catalyzed Cyclization of o‐Alkynylanilines with tert‐Butyl Nitrite: Synthesis and Applications of Indazole 2‐Oxides
Authors: Senadi Gopal Chandru , Wang Ji‐Qi , Gore Babasaheb Sopan , Wang Jeh‐Jeng
Published: June 2017

An efficient method for the synthesis of 1‐benzyl/arylindazole 2‐oxides via a bis(dibenzylideneacetone)palladium(0) [Pd(dba)2]/tert‐butyl nitrite (TBN)‐catalyzed reaction of o‐alkynylaniline derivatives with TBN is reported. The overall transformation involves the formation of three new bonds via N‐nitrosation (N–NO), 5‐exo‐dig cyclization (C–N) and oxidation (C=O). The notable features are the mild reaction conditions, broad substrate scope and dual role of TBN as an NO source and redox co‐catalyst. This strategy was implemented for the synthesis of indazole‐3‐carbaldehyde derivatives and the formal syntheses of pharmaceutically active YC‐1, an anticancer agent (lonidamine), and the male contraceptive experimental drugs AF‐2785 and adjudin (AF‐2364).

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How nano‐scale roughness impacts the flow of grains influenced by capillary cohesion
Authors: LaMarche Casey Q. , Miller Andrew W. , Liu Peiyuan , Leadley Stuart , Hrenya Christine M.
Published: June 2017

Significance

We show that nano‐scale changes in surface roughness affect the macro‐scale (many‐particle) behavior of granular materials influenced by cohesion. Macro‐scale effects of roughness are investigated for conditions where cohesion is dominated by either humidity‐induced or van der Waals‐induced forces. Surface‐topography measurements are used to calculate the relevant interparticle cohesive forces. The (force‐dominated) macro‐scale cohesion measurements are explained via the ratio of the predicted interparticle cohesive force to gravity, thus reinforcing the importance of roughness to cohesion. © 2017 American Institute of Chemical Engineers AIChE J, 63: 5250–5257, 2017
Integrating the physics with data analytics for the hybrid modeling of the granulation process
Authors: AlAlaween Wafa' H. , Mahfouf Mahdi , Salman Agba D.
Published: June 2017

A hybrid model based on physical and data interpretations to investigate the high shear granulation (HSG) process is proposed. This model integrates three separate component models, namely, a computational fluid dynamics model, a population balance model, and a radial basis function model, through an iterative procedure. The proposed hybrid model is shown to provide the required understanding of the HSG process, and to also accurately predict the properties of the granules. Furthermore, a new fusion model based on integrating fuzzy logic theory and the Dempster‐Shafer theory is also developed. The motivation for such a new modeling framework stems from the fact that integrating predictions from models which are elicited using different paradigms can lead to a more robust and accurate topology. As a result, significant improvements in prediction performance have been achieved by applying the proposed framework when compared to single models. © 2017 American Institute of Chemical EngineersAIChE J, 2017
An efficient and reliable predictive method for fluidized bed simulation
Authors: Lu Liqiang , Benyahia Sofiane , Li Tingwen
Published: June 2017

In past decades, the continuum approach was the only practical technique to simulate large‐scale fluidized bed reactors because discrete approaches suffer from the cost of tracking huge numbers of particles and their collisions. This study significantly improved the computation speed of discrete particle methods in two steps: First, the time‐driven hard‐sphere (TDHS) algorithm with a larger time‐step is proposed allowing a speedup of 20–60 times; second, the number of tracked particles is reduced by adopting the coarse‐graining technique gaining an additional 2–3 orders of magnitude speedup of the simulations. A new velocity correction term was introduced and validated in TDHS to solve the over‐packing issue in dense granular flow. The TDHS was then coupled with the coarse‐graining technique to simulate a pilot‐scale riser. The simulation results compared well with experiment data and proved that this new approach can be used for efficient and reliable simulations of large‐scale fluidized bed systems. © 2017 American Institute of Chemical Engineers AIChE J, 63: 5320–5334, 2017
Self‐similar breakup of viscoelastic thread for droplet formation in flow‐focusing devices
Authors: Du Wei , Fu Taotao , Zhang Qindan , Zhu Chunying , Ma Youguang , Li Huai Z.
Published: June 2017

The self‐similarity of the breakup of viscoelastic dispersed thread for droplet formation in flow‐focusing devices is investigated experimentally. A high‐speed camera is used to capture the evolution and angles of the cone‐shaped liquid‐liquid interface. The self‐similar profiles for the liquid‐liquid interface are obtained by normalizing the interface with the minimum width of the dispersed thread. The breakup of the dispersed thread transfers from a self‐similar power law scaling stage with an exponent of 0.36 to a self‐similar exponential scaling stage. The asymptotic cone angles prior to final breakup are consistent with the value of 125.5° and 151°, respectively. The viscoelasticity inhibits the development of finite‐time singularity for the breakup of the liquid‐liquid interface at microscale, similar to the capillary breakup at macroscale. The results demonstrate that the breakup of the viscoelastic dispersed thread for droplet formation exhibits self‐similarity at microscale. © 2017 American Institute of Chemical Engineers AIChE J, 2017
High reproductive effort is associated with decreasing mortality late in life in captive ruffed lemurs
Authors: Tidière Morgane , Lemaître Jean‐François , Douay Guillaume , Whipple Mylisa , Gaillard Jean‐Michel
Published: June 2017

Evolutionary theories of senescence predict that a high allocation to reproduction during early life should have long‐term deleterious consequences on future reproduction or survival because individuals have to face an energy allocation trade‐off between reproductive effort and the maintenance of body condition. Using a high‐quality dataset from 1,721 red ruffed lemurs (RRL,Varecia rubra) and 3,637 black and white ruffed lemurs (BWRM,V. variegata) living in captivity, we tested the existence of a trade‐off between reproductive effort and late‐life survival after accounting for possible confounding effects of natal environmental conditions. We report clear evidence of actuarial senescence (i.e., the decline of annual survival with increasing age) in both sexes and for both species of ruffed lemurs. RRL had a lower baseline mortality and senesced faster than BWRL, resulting in similar distributions of longevities for both species. No between‐sex difference was observed in any species. Lastly, a higher reproductive effort was positively associated with an increase of survival late in life, and thereby an increased longevity. These findings indicate that individual quality rather than trade‐off drives the association between reproductive success and survival pattern among individual lemurs of both species in the protected environment provided by zoos. Lemurs are among the world's highest conservation priorities and better understanding factors influencing their longevity and actuarial senescence patterns should improve their conservation.
Highly Stable, Low Gas Crossover, Proton‐Conducting Phenylated Polyphenylenes
Authors: Adamski Michael , Skalski Thomas J. G. , Britton Benjamin , Peckham Timothy J. , Metzler Lukas , Holdcroft Steven
Published: June 2017

Two classes of novel sulfonated phenylated polyphenylene ionomers are investigated as polyaromatic‐based proton exchange membranes. Both types of ionomer possess high ion exchange capacities yet are insoluble in water at elevated temperatures. They exhibit high proton conductivity under both fully hydrated conditions and reduced relative humidity, and are markedly resilient to free radical attack. Fuel cells constructed with membrane‐electrode assemblies containing each ionomer membrane yield high in situ proton conductivity and peak power densities that are greater than obtained using Nafion reference membranes. In situ chemical stability accelerated stress tests reveal that this class of the polyaromatic membranes allow significantly lower gas crossover and lower rates of degradation than Nafion benchmark systems. These results point to a promising future for molecularly designed sulfonated phenylated polyphenylenes as proton‐conducting media in electrochemical technologies.
The Structure of the Diatom Silaffin Peptide R5 within Freestanding Two‐Dimensional Biosilica Sheets
Authors: Lutz Helmut , Jaeger Vance , Schmüser Lars , Bonn Mischa , Pfaendtner Jim , Weidner Tobias
Published: June 2017

The silaffin peptide R5 is instrumental to the mineralization of silica cell walls of diatom organisms. The peptide is also widely employed in biotechnology, for example, in the encapsulation of enzymes and for fusion proteins in tissue regeneration. Despite its scientific and technological importance, the interfacial structure of R5 during silica precipitation remains poorly understood. We herein elucidate the conformation of the peptide in its active form within silica sheets by interface‐specific vibrational spectroscopy in combination with molecular dynamics simulations. Contrary to previous solution‐state NMR studies, our data confirm that R5 maintains a defined structure when interacting with extended silica sheets. We show that the entire amino acid sequence of R5 interacts with silica during silica formation, leading to the intercalation of silica into the assembled peptide film.
Pentagon‐Embedded Cycloarylenes with Cylindrical Shapes
Authors: Hitosugi Shunpei , Sato Sota , Matsuno Taisuke , Koretsune Takashi , Arita Ryotaro , Isobe Hiroyuki
Published: June 2017

Cylinder‐shaped graphitic networks in carbon nanotubes have attracted interest from scientists in various disciplines. The chemical synthesis of segments thereof is considered as a challenging and appealing subject in chemistry, and deepens our understanding of curved and conjugated arrays of hexagons. We herein report the synthesis of cylinder‐shaped molecules containing non‐hexagon bridges in their conjugated systems. Multiple pentagon units were embedded in the cylinder‐shaped discrete molecules, and the stereoisomerism originating from their helical carbon arrangements was studied. Structural analysis by NMR, UV/Vis absorption spectroscopy, and single‐crystal X‐ray diffraction provided fundamental experimental information on the curved systems with conjugation across the pentagons. This study provides the first experimental guide for further explorations of anomalous non‐hexagon arrays of graphitic carbon materials with cylindrical shapes.
Frustrated Lewis Pair Mediated 1,2‐Hydrocarbation of Alkynes
Authors: Fasano Valerio , Curless Liam D. , Radcliffe James E. , Ingleson Michael J.
Published: June 2017

Frustrated Lewis pair (FLP) chemistry enables a rare example of alkyne 1,2‐hydrocarbation with N‐methylacridinium salts as the carbon Lewis acid. This 1,2‐hydrocarbation process does not proceed through a concerted mechanism as in alkyne syn‐hydroboration, or through an intramolecular 1,3‐hydride migration as operates in the only other reported alkyne 1,2‐hydrocarbation reaction. Instead, in this study, alkyne 1,2‐hydrocarbation proceeds by a novel mechanism involving alkyne dehydrocarbation with a carbon Lewis acid based FLP to form the new C−C bond. Subsequently, intermolecular hydride transfer occurs, with the Lewis acid component of the FLP acting as a hydride shuttle that enables alkyne 1,2‐hydrocarbation.
Ultrasonic‐assisted synthesis and biological evaluation of a nano‐rod diorganotin phosphonic diamide: Precursor for the fabrication of SnP2O7 nano‐structure
Authors: Dorosti Niloufar , Delfan Bahram , Khodadadi Marzieh
Published: June 2017

Nanorods of a diorganotin phosphonic diamide with formula [Sn(CH3)2(Cl)2(L)2]{L = C6H5(O)P(NHC6H11)2} have been synthesized by sonochemical processes at different concentrations without any surfactant or capping agent. The structure and morphology of the prepared complex were investigated by using SEM‐EDAX, XRD, DLS, UV–Vis and FT‐IR spectroscopy. Nanoparticles with well‐defined rod shapes and sizes in the range 30–40 nm have been obtained. Also bulk form of the titled complex was synthesized and characterized by 1H, 13C, 31P, 119Sn NMR, UV–Vis and FT‐IR spectroscopy and compared with its nano‐size. The thermal stabilities at bulk and nano‐size scale have been studied by thermal gravimetric (TG) and differential thermal analysis (DTA). Further, SnP2O7 nanoparticles were synthesized by direct calcination at 730 °C under air atmosphere and characterized using XRD, SEM, and TEM. From XRD measurements, we determined the mean size of the crystallites about 27.4 nm. It is found that the size and morphology of the tin pyrophosphate nano‐structures are dependent upon the particles size of precursor compound as well. Two different forms of metal coordination compound (1a, 1b) and the corresponding ligand (L) were screened for their antibacterial activity against the selected Gram‐positive and Gram‐negative bacteria, showing bactericidal activity for complexes 1a and 1b. In vitro cytotoxicity of compounds was studied against human carcinoma cell lines, A2780 (ovarian cancer) and PC‐3 (prostate cancer). Results indicated that 1a and 1b possess relatively strong cytotoxic activity against cancer cells with IC50 values ranging from 93.2 to 376.2 μM for two exposure time (24 and 48 h).
To prepare the collagen‐based artificial cornea with improved mechanical and biological property by ultraviolet‐A/riboflavin crosslinking
Authors: Zhao Xuan , Long Kai , Liu Yang , Li Weichang , Liu Sa , Wang Lin , Ren Li
Published: June 2017

In the present study, we optimized the ultraviolet‐A (UVA)/riboflavin crosslinking for the collagen‐based artificial cornea for the first time to resolve the lack of donor cornea for corneal disease. We found that the crosslinking conditions, including irradiation time and irradiation intensity, played important roles on the property of the sample. At the optimal condition (with the irradiation time of 30 min and the irradiation intensity of 5 mW/cm2), the sample exhibited excellent crosslink degree and mechanical property while keeping good light transmittance. Meanwhile, the sample showed improved enzyme tolerance capacity and thermal stability. This developed artificial cornea also had good biocompatibility to human corneal epithelial cells in vitro. In vivo lamellar keratoplasty results showed that the developed sample could promote complete epithelialization in about 4 weeks, and the transparency is restored quickly in the first 6 weeks. Corneal rejection reaction and keratoconus are not observed. This optimized UVA/riboflavin crosslinking method would have great potential for collagen‐based artificial cornea in clinic. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45226.
Isotactic polypropylene–vapor grown carbon nanofibers composites: Electrical properties
Authors: Aldica Gheorghe Virgil , Ciurea Magdalena Lidia , Chipara Dorina Magdalena , Lepadatu Ana Maria , Lozano Karen , Stavarache Ionel , Popa Stelian , Chipara Mircea
Published: June 2017

Nanocomposites have been obtained by dispersing various amounts of vapor grown carbon nanofibers within isotactic polypropylene. Thermal investigations done by differential scanning calorimetry and dynamic mechanical analysis revealed the effect of the vapor grown carbon nanofibers on the melting, crystallization, α, and β relaxations. Direct current electrical features of these nanocomposites have been investigated and related to the thermal features of these nanocomposites. The effect of the loading with carbon nanofibers on the electrical properties of these nanocomposites is discussed within the percolation theory. The percolation threshold was estimated at about 5.5% wt carbon nanofibers. The temperature dependence of the direct current conductivity is analyzed in detail and it is concluded that the electronic hopping is the dominant transport mechanism. A transition from one‐dimensional hopping towards a three‐dimensional hopping was noticed as the concentration of carbon nanofibers was increased from 10% wt to 20% wt carbon nanofiber. The possibility of a differential negative resistivity is suggested. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45297.
Microporous PDMAEMA‐based stimuli‐responsive hydrogel and its application in drug release
Authors: Chen Yi , Liu Wenyong , Zeng Guangsheng , Liu YueJun
Published: June 2017

The microporous hydrogels (Pn‐Cm gels) composed of poly(dimethylaminoethyl methacrylate) and carboxymethylchitosan were synthesized in situ radical polymerization by using nano γ‐Fe2O3 particles as pore‐agent. The microporous structure formed through eliminating the Fe2O3 particles was designed to achieve a faster response rate and better drug loading effect. Comparing to the neat gels, Pn‐Cm gels exhibit deteriorative mechanical properties with the increased pores, while the gels still keep the elastic network structure which could bear some degree of tensile and compression deformation. Meantime, Pn‐Cm gels show similar temperature and pH double responsiveness with same isoelectric point shrink as that of neat gels, the swelling ability decreases slightly, and the deswelling rate increases with the increase of pores. Moreover, the 5‐fluorouracil was used as a target drug to explore the potential of this gel applied as drug‐release system. For Pn‐Cm gels, the more pores and carboxymethyl chitosan inside the gels are beneficial to the drug loading, all gels show a burst release of drug, being followed by a slow and sustained release with different rate. Comprehensively, the Pn‐Cm gels exhibit a better sustained release effect in the simulated stomach condition (pH = 2.1), the related release mechanism could be interpreted by the superposition of Fickian diffusion. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45326.
Ionic‐liquid‐assisted three‐dimensional caged silica ablative nanocomposites
Authors: Kumar Vijay , Kandasubramanian Balasubramanian
Published: June 2017

In this study, we demonstrated a novel three‐dimensional network of thermally stable fumed silica (FS)–resorcinol formaldehyde (RF) nanocomposites via an ionic‐liquid (IL)‐assisted in situ polycondensation process. The study involved subjecting the tailored nanocomposites to thermogravimetric analysis and oxyacetylene flame environment as per ASTM test standards for thermal ablative performance. X‐ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, high‐resolution transmission electron microscopy, Raman spectroscopy, and wettability studies were undertaken to underline the improvement correlation in the microstructure and material properties. Significant reductions in the linear ablation rate (66%) and mass ablation rate (26.6%), along with lower back‐face temperature profiles, marked enhanced ablative properties. The increased char yield (33.3%) and higher temperatures for weight losses evinced the improved thermal stability of the modified RF resin. The uniformly dispersed fused nanosilica with a glassy coating morphology on the ablative surface acted as barrier to oxidation. The results signify that the IL‐assisted modification of the RF resin with FS significantly enhanced ablative performance. A viable replacement to the conventional phenolic nanocomposites for thermal ablative applications to buy critical time for the containment and suppression of thermal‐heat‐flux threats is of paramount importance. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45328.
A new sulfonated poly(ether sulfone) hybrid with low humidity dependence for high‐temperature proton exchange membrane fuel cell applications
Authors: Molavian Mohammad Reza , Abdolmaleki Amir , Firouz Tadavani Koorosh , Zhiani Mohammad
Published: June 2017

A new sulfonated poly(ether sulfone) (PES) hybrid with low humidity dependence was prepared based on a new synthesized PES and Udel as a commercial PES. The PES was synthesized based on a pyridine containing diol which is able to change between pyridine and pyridinium salt forms during the cell performance (acidic condition) and facilitate proton transfer. The presence of nitrogen group increases inter and intramolecular interactions in the membrane and enhance proton hopping mechanism. Thermogravimetrical analysis of PES hybrid shows good thermal stability. Proton conductivity measurements were evaluated on a fuel cell test station, showing that the membrane has better performance under lower humidity (relative humidity = 60%) compare to the fully hydrated condition (relative humidity = 100%). The results reveal that proton transfer might be mainly accomplished through proton hopping mechanism at higher temperatures. The membrane also shows significant proton conductivity at 120 °C (about 6.6 mS cm−1 at RH = 30%). © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45342.
Alkylated pectin hydrogels as potential protein drug carriers
Authors: He Xiao‐hong , Liang Rui‐hong , Liu Cheng‐mei , Liu Wei , Chen Rui‐yun , Hu Xiao‐xue , Chen Jun
Published: June 2017

Pectin has been used in the development of safe and effective drug delivery systems because of its unique physicochemical and biological characteristics. However, it still needs to be modified to overcome some inherent drawbacks. In the present study, pectin was alkylated by bromododecane. The C12‐alkylated pectin (PC12) can form strong hydrogels in the presence of Ca2+. Such hydrogels were explored to prepare bovine serum albumin (BSA)‐loaded microspheres (PC12‐MS). The BSA encapsulation yield of PC12‐MS was significantly higher than that of microspheres prepared with the original pectin (PC‐MS). Differential scanning calorimetry analysis indicated that interactions existed between BSA and pectin during the preparation of microspheres. Release tests showed that PC12‐MS almost avoided BSA release in simulated gastric fluids, which was verified by environmental scanning electron microscopy analysis, and exhibited an effective controlled release throughout the simulated gastrointestinal tract compared to PC‐MS. In addition, an MTT assay showed the biocompatibility of C12‐alkylated pectin. Thus alkylated pectin may serve as a potential protein drug carrier. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45344.
Fabrication and characteristics of graphene oxide/nanocellulose fiber/poly(vinyl alcohol) film
Authors: Xu Changyan , Shi Lina , Guo Lu , Wang Xi , Wang Xinyi , Lian Hailan
Published: June 2017

Poly(vinyl alcohol) (PVA), PVA/nanocellulose fiber (CNF), and PVA/CNF/graphene oxide (GO) films were prepared simply by casting stable aqueous mixed solutions. FTIR investigation indicated that hydrogen bonding existed between the interface of GO and PVA‐CNF. Scanning electron microscopy and X‐ray diffraction analysis showed that GO was uniformly dispersed in PVA‐CNF matrix. Introducing CNF into PVA caused a significant improvement in tensile strength, and further incorporating GO into PVA/CNF matrix led to a further increase. The tensile strength of the neat PVA film, PVA/CNF composite, and PVA/CNF/GO film (0.6 wt % GO) was 43, 69, and 80 MPa, respectively. Moreover, when incorporating 8 wt % CNF into PVA matrix, O2 permeability and water absorption decreased from 13.36 to 11.66 cm3/m2/day and from 164.2% to 98.8%, respectively. Further adding 0.6 wt % GO into PVA/CNF matrix resulted in a further decrease of permeability and water absorption to 3.19 cm3/m2/day and 91.2%, respectively. Furthermore, for all composite samples, the transmittance of visible light was higher than 67% at 800 nm. CNF and GO‐reinforced PVA with high mechanical and barrier properties are potential candidates for packaging industry. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45345.
On horizontal distribution of vertical gradient of atmospheric refractivity
Authors: Grabner Martin , Pechac Pavel , Valtr Pavel
Published: June 2017

The horizontal distribution of the vertical gradient of atmospheric refractivity is important for the assessment of the propagation of electromagnetic waves on nearly horizontal paths. A 5‐year set of meteorological data, obtained from the ERA‐Interim numerical weather product, has been used to analyze this distribution statistically. Vertical gradient maps of the Central European region have been processed to derive empirical probability distributions of the difference between local point gradient values at two locations. The difference of the effective (path‐averaged) gradient along the path and the local gradient is shown to be statistically distributed so that the quantiles increase linearly with distance in the interval from 100 to 1000 km. Finally, a spatial correlation function is obtained and described by an exponential model with correlation distances determined in the range of 400–700 km.
Screening Viral Neuraminidase Inhibitors Using a Glycosylated N1 Structure Model Derived From Molecular Dynamics Simulations
Authors: Choi Youngjin , Lee Jung‐kyu , Kang In‐Cheol , Jung Seunho
Published: June 2017

We present a novel drug screening approach for discovering neuraminidase inhibitors, in which viral neuraminidase is a well‐characterized target to develop anti‐influenza pharmaceuticals. In this study, a series of molecular dynamics‐driven structures for a glycosylated form of the neuraminidase N1 was introduced during an in silico screening process. The efficiency of this approach was confirmed by activity‐based in vitro screening for inhibitory chemicals of the neuraminidase from H1N1 (A/California/04/2009). This is the first report on a virtual screening method for neuraminidase using a computational glycosylated structure model for N1.
Why today's police officer should be required to be college‐educated
Authors: Mabry Kendall
Published: June 2017

Law enforcement responsibilities have evolved over the years. More than 350 years ago in the United States, communities saw a need for law and order, and volunteers began unofficial law enforcement units. The “policemen” of those societies were often tasked with more straightforward policing responsibilities that did not necessarily require the breadth of knowledge needed by police officers today, even for rudimentary functions.