bluuebunny/crossref_metadata_2025 huggingface dataset:
La distribución de la tierra y el crecimiento económico de la campaña de Buenos Aires. Un estudio de la región oeste, 1839-1867
Authors: Barcos María Fernanda
Published: May 2018

En Buenos Aires, el periodo que transcurre entre 1839 y 1869 se caracterizó por un crecimiento económico casi constante. Dicho proceso generó una creciente desigualdad en la distribución de la riqueza (fundamentalmente de la tierra) pero produjo una importante movilidad social, sobre todo entre 1839 y 1855. La región oeste presenta particularidades bien marcadas en el proceso señalado que aún no han sido estudiadas en detalle. A partir del análisis conjunto del impuesto de la contribución directa y los expedientes de tierras, se estudian las causas del movimiento diferencial que se operó allí. Se analizan los partidos de Chivilcoy, Mercedes y Suipacha (expartido de la Guardia de Luján hasta 1845) porque sintetizan muy bien los cambios operados en la región de estudio.
Clinical Outcomes of Aspirin Interaction with Other Non-Steroidal Anti-Inflammatory Drugs: A Systematic Review
Authors: Alqahtani Zuhair , Jamali Fakhreddin
Published: May 2018

Purpose: Concomitant use of some non-Aspirin nonsteroidal anti-inflammatory drugs (NANSAIDs) reduces the extent of platelet aggregation of Aspirin (acetylsalicylic acid). This is while many observational studies and clinical trials suggest that Aspirin reduces cardiovascular (CV) risk attributed to the use of NANSAIDs. Thus, the therapeutic outcome of the interaction needs to be assessed. Methods: We searched various databases up to October 2017 for molecular interaction studies between the drugs and long-term clinical outcomes based on randomized clinical trials and epidemiological observations that reported the effect estimates of CV risks (OR, RR or HR; 95% CI) of the interacting drugs alone or in combinations. Comparisons were made between outcomes after Aspirin alone, NANSAIDs alone and Aspirin with naproxen, ibuprofen, celecoxib, meloxicam, diclofenac or rofecoxib. Results: In total, 32 eligible studies (20 molecular interactions studies and 12 observational trials) were found. Conflicting in vitro/in vivo/ex vivo platelet aggregation data were found for ibuprofen, naproxen and celecoxib. Nevertheless, for naproxen, the interaction at the aggregation level did not amount to a loss of cardioprotective effects of Aspirin. Similarly, for ibuprofen, the results overwhelmingly suggest no negative clinical CV outcomes following the combination therapy. Meloxicam and rofecoxib neither interacted with Aspirin at the level of platelet aggregation nor altered clinical outcomes. The clinical outcomes data for celecoxib and diclofenac are in conflict. Conclusion: Aspirin appears to maintain its cardioprotective effect in the presence of naproxen, ibuprofen, meloxicam and rofecoxib. The limited available data suggest that the effect of interaction at the platelet aggregation level may dissipate shortly, or the reduced platelet aggregation yielded by the interaction may be sufficient for cardioprotection; i.e., no need for near complete aggregation. In addition, cardioprotective effect of Aspirin, despite reduced platelet aggregation caused by NANSAIDs, may be through its involvement in other mechanisms such as the renin-angiotensin system and/or metabolism of arachidonic acid to biologically active compounds mediated by cytochrome P450. This article is open to POST-PUBLICATION REVIEW. Registered readers (see “For Readers”) may comment by clicking on ABSTRACT on the issue’s contents page.
Clarity and Visual Ratios of the Vibrant Place Making
Authors: Shakir Alkinani A , Hamzah Najm H , Hamed Abid Ateaa E
Published: May 2018

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Siting of Proposed Areas for Urban Agriculture in the City of Baghdad
Authors: Saddek G , Khleefah Alrikabi N , Abbas Ahmed Z
Published: May 2018

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Toward Sustainable Compact City: (Study in Convert Traditional Najaf City to Sustainable Compact City)
Authors: Dheyaa Al-Shouk N , Shamkhi Al-Khfaji A
Published: May 2018

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The Spatial Planning for the Educational Services and the Scarcity of Urban Land: Study Area: Al-Sadder City
Authors: Kamil Flayeh M , Kareem Hamil A
Published: May 2018

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Iraq’s Transport Strategy
Authors: Kamil Flayeh M
Published: May 2018

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Economic and Social Costs of Random Hostels in Algeria
Authors: Rahima H
Published: May 2018

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Strategic Spatial Planning Consideration in the Kingdom Vision 2030 and National Physical Planning Plan: Utilizing Content Analysis Methodology for Evaluation and Comparison
Authors: Ali Alribah H , Jarallah Al-Jarallah A
Published: May 2018

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PERGESERAN DAN PERKEMBANGAN TERMA MUTAWATTIR DALAM STUDI HADIS
Authors: Afwadzi Benny
Published: May 2018

This article discusses about displacement and development of mutawatir in hadith studies. The author finds that the term did not recognized in classical period of hadith studies and clearly introduced by Ibnu Salah (7 H.). The term was developed significantly by Ibnu Hajar (9 H.). After the emergence of Ibnu Hajar, mutawatir hadith became popular discourse and discussed by most of scholars. In this article, the author concludes that there are several displacements and developments, first, mutawatir hadith initially form a part of masyhur hadith and then standed independently on its afters works. Second, the number of mutawatir hadith were added significant, on its beginning not available, then said available one, and then developed continually. Third, the categorization of mutawatir hadith was added from one period to other period, lafzi, ma’nawi, and ‘amali. Fourth, in the early recognition, the numbers of transmitter ranging on fourty persons, and then fluctuated until number of ten persons becomes the popular opinion.
TAFSIR MISOGINIS AYAT-AYAT IDDAH: Analisis Sosiologis Ayat-Ayat Iddah Menurut Mufassir dan Ahli Fiqh
Authors: Muttakin Khairul
Published: May 2018

One issue that arises today is about the waiting period for women, either died or idda divorce waiting period. Because the prescribed period (of waiting) for women in a relatively long period of time. If that be the reason for the length of the prescribed period, one of which, is to determine about the possibility of the women were pregnant or not  then with modern technology can already be known to women pregnant or not without having to wait for several months. This is the theme of the discussion in this article because the waiting period (iddah) for women under the spotlight from opponents who take the position of Islamic law (the issue of the prescribed period for women) tend to be unreasonable. In addition glare comes from the feminist questioning the prescribed period like women only, while the male is no such thing prescribed period and may not directly get married after the divorce. This will bring up the notion that the verses of the Koran that talk about issues iddah tend misogynistic and view women are lower than men's. By combining the approach of islamic law and the interpreter opinion of classical and modern would be associated with the formulation of Islamic law more reasonable and acceptable, especially for opponent.
KILAS BALIK KALENDER HIJRIYAH INDONESIA PERJALANAN MENUJU PENYATUAN KALENDER NASIONAL
Authors: Hosen Hosen
Published: May 2018

The discourse of unification of hijri calendar in Indonesia became the topic of discussion which always colored throughout the year. Once the importance of the hijri calendar to unite its determination so that there is not always a difference in its determination, especially related to worship such as the beginning of Ramadlan, Syawwal and Dzulhijjah. It is hoped that with one reference to the hijri calendar, religious worship can run in unity for all Indonesian people identical with the unitary state. The existence of various streams and methods that developed in Indonesia in determining the beginning of the month of hijriyah, themes that are crucial and can not be compromised for the unification of the calendar, as well as efforts that have been made to realize the hijri calendar as a national calendar. The existence of Islamic organizations such as NU and Muhammadiyah turned out to have a greater influence in the system of hijri calendar. The State through the Ministry of Religion can not be a single authority who is entitled to issue a reference hijri calendar that must be obeyed by all Indonesian people.
Effects of Liquefaction Temperature and Time on Characterization of Liquefied Oil Palm Trunk Residue in the Presence of Polyhydric Alcohols
Authors: Choowang Rattana , Lin Jian , Zhao Guangjie
Published: May 2018

Resides derived from liquefaction of oil palm trunk in the presence of polyhydric alcohol with different liquefaction temperature and time were characterized to provide a new approach to understand some fundamental aspects of the liquefaction reaction. Higher temperature and longer reaction time resulted in lower residue content, indicating more decomposition of components of oil palm trunk. The amorphous polymer comprised of lignin, hemicellulose, starch, and cellulose with non-crystalline structure are firstly degraded at low liquefaction temperature, followed by the decomposition of crystalline region of cellulose. Although it was relatively difficult to destroy the ordered structure of cellulose, most of them could be liquefied via prolonging reaction time or enhancing reaction temperature. Nevertheless, it was found that re-condensation of liquefied products occurred during the liquefaction process when higher temperature of 180 oC was used after 60 min, leading to the gradual increase of residue content with increase of reaction time.
The Pollutant Particle Size and Chemistry Matters
Authors: Kodzius Rimantas , Khdr Dana , Rabiei Nima , Fattah Asan , Wang Xiaohong , Liu Jinfeng , Gong Xiuqing , Damiati Samar
Published: May 2018

The air is not the same as thousands and hundreds of years ago. In the air, suspended particles originate from natural phenomena like dust storms or volcanic activities, as well as anthropogenic pollutants such as fuel engine exhaust and everyday activities at home. The total particles in the air can be classified by sizes, such as PM10, PM2.5 or ultrafine particles. However, there are many other important factors in addition to the particle size, influencing the particle behavior and affecting our health. The surface area, chemical and biological composition, aspect ratio, and the charge are all factors characteristic of particles. OoC microfluidic chips are very useful for the pollutant toxicity measurements on various body tissues. A better understanding of pollutants will help to trace these to the potential sources. The data from the on-the-ground and satellite monitoring can be integrated into models, helping to predict and prevent pollution exposure.
Antioxidant, Mechanical and Physical Properties of Chicken Skin Gelatin/CMC Film Incorporated with Centella asiatica Extract
Authors: Mohd Nazmi Nur Nasihah , Mhd Sarbon Norizah
Published: May 2018

This study aimed to characterize the antioxidant, mechanical and physical properties of chicken skin gelatin/CMC/Centella asiatica blended film. The influence of Centella asiatica at 0.3% and 0.7% on antioxidant activities; mechanical properties and physical properties of chicken skin gelatin/CMC/Centella asiatica film were investigated. Characterization of the blended films with 0.7% Centella asiatica extract shows higher antioxidant activities with a total phenolic content of 0.36 mg/g of GAE, DPPH of 89.26%, and reducing power of 0.80 nm compared to 0.3% Centella asiatica extract. The addition of 0.3% of Centella extract provide higher value in tensile strength (5.0 × 10−2 MPa), elongation at break (281%), melting point (131.31 °C), transparency (0.86) but lower UV-light penetration. While the addition of 0.7% Centella extract contribute to higher value in WVP (1.13 × 10−4 g m−1s−1Pa−1) and puncture test (0.06 N). There are no significant differences between functional groups obtained from this blended film as evaluated by FTIR analysis (p > 0.05). Furthermore, XRD analysis showed the addition of extract decrease the crystallinity of film. In conclusion, the incorporation of Centella asiatica extracts on film greatly increased antioxidant levels and improved some of the mechanical and physical properties of the film blends.
Construct Validity of Korean Leisure Sports Instructor Job Crafting Questionnaire Scale (KSIJCQ: Korean Sports Instructor JCQ)
Authors: Kim Wook Kyung , Chung Won Chung , Park Hyu Kyoung
Published: May 2018

In previous researches, Job Crafting questionnaire to develop is consists of 3 factors which are Task Crafting, Cognitive Crafting, and Relationship Crafting with 12 to 17 items. The purpose of study is to develop JCQ for leisure sports instructor of Korean. 274 valid samples are used for analysis. Data collecting is purposeful sampling. At result, for Korean Sports Instructor Job Crafting Scale is constructed 3 factors with 12 items is constructed by 3 step procedure. KSIJCQ is confirmed on convergent discriminant validity evidence. In conclusion, KSIJCQ is a valid scale of the measuring and distributes Job Crafting of generalization in sports.
Changing Trends in Computational Drug Repositioning
Authors: Yella Jaswanth K. , Yaddanapudi Suryanarayana , Wang Yunguan , Jegga Anil G.
Published: May 2018

Maximizing the indications potential and revenue from drugs that are already marketed offers a new take on the famous mantra of the Nobel Prize-winning pharmacologist, Sir James Black, “The most fruitful basis for the discovery of a new drug is to start with an old drug”. However, rational design of drug mixtures poses formidable challenges because of the lack of or limited information about in vivo cell regulation, mechanisms of genetic pathway activation, and in vivo pathway interactions. Most of the repositioned drugs therefore are the result of “serendipity” - based on late phase clinical studies of unexpected findings. One of the reasons that the connection between drug candidates and their potential adverse drug reactions or new applications could not be identified earlier is that the underlying mechanism associating them is either very intricate and unknown or dispersed and buried in a sea of information. Discovery of such multi-domain pharmacomodules - pharmacologically relevant sub-networks of biomolecules and/or pathways - from collection of databases by independent/simultaneous mining of multiple datasets is an active area of research. Here, while presenting some of the promising bioinformatics approaches and pipelines, we summarize and discuss the current and evolving landscape of computational drug repositioning.
Improving Observing Skills of High School Students through Guided Inquiry Model
Authors: Sahnaz Shafila , Harlita Harlita , Ramli Murni
Published: May 2018

 

  Observation skill is one of the fundamental science process skills should mastered by students in the primary level. In fact, due to the lack of experiences of observation, high school students in the observed class showed the low level of observations skills. This study was three cycles-collaborative action research aims to improve the observation skills of high school students in biology through the implementation of guided inquiry learning integrated with a series of observation activities. The participants were 30 students of grade 11 of one public high school in Karanganyar, Indonesia. Six indicators of observation skills were used to assess the performance of students. In the pre-cycle stage, students showed relatively moderate performance on two aspects, e.g., identifying the differences and similarities of objects (45.83), and using of multiple senses to observe (45.83). But, they performed low in uses the apparatus correctly (4.17). On the skills of classifying the differences or the similarities, they scored 25, and for collecting relevant data they got 29.17 in average. After three iterative cycles, all indicators have increased significantly. 

 
An Intervention-Based Active-Learning Strategy To Enhance Student Performance in Mathematics
Authors: Sidhu Gaganpreet , Srinivasan Seshasai
Published: May 2018

Experiments were performed to study the effect of integrating an intervention strategy on student learning in an active learning environment in three different undergraduate mathematics courses. In these pedagogical experiments, the learning was measured via several subjective tests and the overall final grade for each course. For each course the comparison was made between two sections, one receiving the material via traditional instruction (control section) and the second receiving the material via instruction based on the active learning strategy (experimental section). It was found that students taught using the latter approach performed significantly better in the tests and exams, reflecting a good understanding of the material.
Current Season Photoassimilate Distribution in Sweet Cherry
Authors: Ayala Marlene , Lang Gregory
Published: May 2018

Sweet cherry (Prunus avium) tree canopies comprise three types of leaf populations: fruiting spur (FS), nonfruiting spur (NFS), and extension shoot (ES) leaves. The contribution of each leaf population as sources of photoassimilate synthesis and distribution for sweet cherry fruit development has not been described previously. To determine how carbon fixed by different leaf populations is distributed to reproductive and vegetative sinks during fruit development, fruiting branches of 7-year-old ‘Ulster’ sweet cherry trees grown on ‘Gisela®6’ (Gi6) (Prunus cerasus × Prunus canescens) rootstock at Michigan State University’s Clarksville Research Center (Clarksville, MI) were exposed to 13CO2 labeling on five dates in 2003 [25, 40, 44, 56, and 75 days after full bloom (DAFB), which occurred on 30 Apr.], comprising the period from late Stage I (SI) to late Stage III (SIII) of fruit development. Forty-eight hours after labeling, whole branches were removed and separated into different organs for 13C analysis by gas chromatography–mass spectrometry (GC-MS). The organs analyzed included: FS leaves, NFS leaves, ES leaves, fruit, and wood + bark from the segment of the branch corresponding to each leaf population. Relative distribution of C from each leaf population source to each sink varied during fruit development. Overall, the proportion of 13C recovered in the fruit was highest for the FS leaf population (which included fruit exposure to 13CO2), followed by the NFS leaves, then ES leaves. From SI to SIII, ≈60% of the 13C recovered in the FS portion of the branch was found in the fruit, except during the exponential growth of fruit in mid-SIII (56 DAFB) when this proportion was nearly 80%. About 30% of the 13C fixed by NFS leaves was found in the fruit during Stage II (SII) (40 DAFB) and early (44 DAFB) and late (75 DAFB) SIII, with higher proportions at SI (45% at 25 DAFB) and mid-SIII (70%). About 25% of the 13C fixed by ES leaves was found in the fruit during SI, SII, and late SIII, with a lower proportion (17%) at early SIII when shoot growth was exponential, and a higher proportion (nearly 60%) at mid-SIII. The proportion of 13C fixed and translocated to ES growth was minimal from FS and NFS leaves throughout the sampling dates, but that by the ES leaves was significant, peaking at early SIII. The results illustrate the dynamics of C contribution from each leaf population between vegetative and reproductive sinks during growth in sweet cherry orchards, which provides useful physiological information for canopy pruning and crop load regulation.
Cytological Features of Developing Anthers in Rose Balsam
Authors: Yang Shujuan , Peng Li , Bao Han , Tian Huiqiao
Published: May 2018

Our goal was to determine the ultrastructure features and the dynamic changes in polysaccharides and neutral lipids in developing anthers of rose balsam (Impatiens balsamina), and to better understand the mechanisms controlling male reproductive development. Transmission electron microscope (TEM) techniques were used to study the ultrastructural characteristics of the anthers, and histochemical methods were used to determine levels of polysaccharides and lipids. The cytokinesis in the microsporocyte meiosis was simultaneous type, and microspore tetrads were mainly tetrahedral. The pollen exine began to form at the tetrad stage. The mature pollen grains were oval-shaped and bicellular. Accumulation of reserve substances began at the late microsporogenesis stage, and an abundance of starch grains and lipids were stored in pollen grains at anthesis. Polysaccharides and lipids changed in different stages and played an important role in anther development. Moreover, the calcium oxalate crystals may protect the pollen and suggest that calcium distribution is related to anther development.
Litchi Flowering is Regulated by Expression of Short Vegetative Phase Genes
Authors: Hu Jiaqi , Kim Hye-Ji , Chen Houbin , Zhou Biyan
Published: May 2018

Short vegetative phase (SVP), a MADS-domain transcription factor, was shown to act as a repressor of flowering in arabidopsis (Arabidopsis thaliana). Although the role of SVPs in flowering is well characterized in the model plant arabidopsis, little is known in evergreen woody litchi (Litchi chinensis). In this study, three litchi SVP homologs (LcSVP1, LcSVP2, and LcSVP3) were cloned, and the bioinformatic analysis of the LcSVPs was carried out to identify their molecular characteristics. Their expression patterns in the apical meristem (AM) during the transition from vegetative to reproductive phase were studied under natural flowering inductive conditions. Also, brassinosteroid (BR) treatment under low temperature conditions was performed to elucidate the role of LcSVPs in the BR-regulated flowering. The results showed that LcSVPs belonged to the MADS superfamily. LcSVP relative expression levels in AMs of the early- and late-flowering cultivars showed decreasing trends with the transition from vegetative to reproductive growth. Under low temperature condition, relative expression levels of LcSVP1, LcSVP2, and LcSVP3 in AMs or panicle primordia showed decreasing trends, whereas those in the AMs of the BR-treated trees remained at relatively high levels. Relative expression analysis of the litchi homolog, flowering locus t 1 (LcFT1), showed that the BR-treated leaves had lower relative expression level than nontreated control leaves. The findings suggest that LcSVPs act as repressors involved in flowering in natural conditions and the BR-regulated flowering.
A Fault Detection Method for Combinational Circuits
Authors: Zoraghchian AliAbbass , Didehban Moslem , Mehrabian Mohammad Reza
Published: May 2018

As transistors become increasingly smaller and faster and noise margins become tighter, circuits and chip specially microprocessors tend to become more vulnerable to permanent and transient hardware faults. Most microprocessor designers focus on protecting memory elements among other parts of microprocessors against hardware faults through adding redundant error-correcting bits such as parity bits. How ever, the rate of soft errors in combinational parts of microprocessors is consider edas important as in sequential parts such as memory elements nowadays. The reason is that advances in scaling technology have led to reduced electrical masking .This paper proposes and evaluates a logic level fault-tolerant method based on parity for designing combinational circuits. Experimental results on a full adder circuit show that the proposed method makes the circuit fault-tolerant with less overhead in comparison with traditional methods. It will also be demonstrated that our proposed method enables the traditional TMR method to detect multiple faults in addition to single fault masking.
A Fast Optical Spectrum Data Acquisition Method Based on FPGA and DSP
Authors: Xu Liqun , Jiaming Gong
Published: May 2018

This paper presents a fast CCD optical spectrum data acquisition method based on FPGA, FIFO and DSP. Introduces a linear CCD timing sequence control signal generation and high speed ADC interface with FIFO and DSP in detail, publishes this design key parts FPGA logic schematic and VHDL source code, provides a general solution for universal high speed CCD optical spectrum data acquisition and analysis system.
A Disparateness-Aware Scheduling using K-Centroids Clustering and PSO Techniques in Hadoop Cluster
Authors: Lydia E. Laxmi , Swarup M.Ben
Published: May 2018

Big data storage management is one of the most challenging issues for Hadoop cluster environments, since large amount of data intensive applications frequently involve a high degree of data access locality. In traditional approaches high-performance computing consists dedicated servers that are used to data storage and data replication. Therefore to solve the problems of Disparateness among the jobs and resources a “Disparateness-Aware Scheduling algorithm” is proposed in the cluster environment. In this research work we represent K-centroids clustering in big data mechanism for Hadoop cluster. This approach is mainly focused on the energy consumption in The Hadoop cluster, which helps to increase the system reliability. The Hadoop cluster consists of resources which are categorized for minimizing the scheduling delay in the Hadoop cluster using the K-Centroids clustering algorithm. A novel provisioning mechanism is introduced along with the consideration of load, energy, and network time. By integrating these three parameters, the optimized fitness function is employed for Particle Swarm Optimization (PSO) to select the computing node. Failure may occur after completion of the successful execution in the network. To improve the fault tolerance service, the migration of the cluster is focused on the particular failure node. This can recomputed the node by PSO and the corresponding optimal node is predicted. The experimental results exhibit better scheduling length, scheduling delay, speed up, failure ratio, energy consumption than the existing systems.
Aircraft Design Analysis, CFD and manufacturing
Authors: El-Sadi Haifa
Published: May 2018

Aircraft design, manufacturing and CFD analysis as part of aerodynamic course, the students achieve sizing from a conceptual sketch, select the airfoil geometry and the tail geometry, calculate thrust to weight ratio and wing loading, use initial sizing and calculate the aerodynamic forces. The students design their aircraft based on the geometrical dimensions resulted from the calculations and use the model to build a prototype, test it in wind tunnel and achieve CFD analysis to be compared with the experimental results. The theory of aerodynamic is taught and applied as a project based. In this paper, the design process, aircraft manufacturing and CFD analysis are presented to show the effect of project based on student’s learning of aerodynamic course. This project based learning has improved and accelerated students understanding of aerodynamic concepts and involved students in a constructive exploration.

The analysis of the aircraft resulted in a study that revolved around the lift and drag generation of this particular aircraft. As to determine the lift and drag forces generated by this plane, a model was created in Solidworks a 3-D model-rendering program. After this model was created it was 3-D printed in a reduced scale, and subjected to wind tunnel testing. The results from the wind tunnel lab experiment were recorded. For accuracy, the same 3-D model was then simulated using CFD simulation software within Solidworks and compared with the results from the wind tunnel test. The values derived from both the simulation and the wind tunnel tests were then compared with the theoretical calculations for further proof of accuracy.
The Research of Direct Torque Control Based on Space Vector Modulation
Authors: Xiaohui Su , Guodong Chen , Shuping Xu
Published: May 2018

In order to solve the conventional direct torque control contradiction between the dynamic and static performance ,a permanent magnet synchronous motor system direct torque control architecture is proposed based on space vector modulation strategy . In this method flux and torque are controlled through stator voltage components in stator fluxlinkage coordinate axes and space vector modulation is used to control inverters.The simulation verifies that SVM-DTCis capable of effectively improving the steady state performance and keeping the excellent dynamic performance of theconventional DTC system simultaneously and remain the switching frequency constant.
A DCT Domain Image Watermarking Method Based on Matlab
Authors: He-Jing Wu
Published: May 2018

In the text, A method of image watermarking based on DCT (Discrete Cosine Transform) domain algorithm is proposed and verified in experiment by Matlab. The experimental result shows that the current method can achieve embedding with sound robustness and invisibility. From the experimental results, the quality of the watermarked image is almost no decline relative to the original.
Optimal Pricing Strategies for Resource Allocation in IaaS Cloud
Authors: Cai Zhengce , Li Xianwei
Published: May 2018

In cloud computing environment, pricing is an effective method for resource allocation and it provides efficient incentive for cloud providers to provide cloud services. In this paper, we investigate two pricing schemes for the allocation of cloud resources in a monopoly cloud market subject to constrained capacity of the cloud provider. There are two main pricing schemes, on-demand and reserved pricing mechanisms adopted by leading cloud providers, i.e., Amazon and Gogrid. We analyze how cloud users make their choice decisions to subscribe to cloud resources under different pricing schemes.
Image Watermarking Encryption Scheme Based on Fractional Order Chaotic System
Authors: Ding Dawei , Li Zongzhi , Li Shujia
Published: May 2018

Now the chaotic system and wavelet transform are more and more widely used in the watermarking technology. At the same time, the fractional order chaotic system has more complex dynamic characteristics than the integer order system. So a new image watermarking scheme based on the fractional order Chen chaotic system and discrete wavelet transform is proposed. Chaotic sequences generated by chaotic system are used to encrypt the watermark image, and the processed watermark information is embedded into the original image by the discrete wavelet transform. Finally, the security analysis of the proposed watermarking algorithm is presented. The experimental results show that the proposed watermarking scheme has high security, and it has stronger robustness and invisibility compared with the previous work.
Corn Residue Particle Size Affects Soil Surface Properties
Authors: Stetson Sarah J. , Lehman R. Michael , Osborne Shannon L.
Published: May 2018

Core Ideas

Corn harvesting practices generate characteristic residue particle size distributions.

Corn residue particle size influences its composition and decomposition.

Residue particle composition and decomposition influence soil properties, i.e., soil C and N.

Mechanical harvesting operations affect soil properties via residue size distributions.

Field operations may differentially influence crop residue size distributions, altering residue decomposition rates and soil carbon (C) and nitrogen (N) dynamics. In a laboratory microcosm study modeling corn residue distributions observed in a no‐till cropping system, microbial respiration was initially (first 30 d) inversely proportional to residue particle size across four size classes. Subsequently (30–60 d), respiration in the smallest particle size decreased in relation to the larger size classes. Residue particle size significantly increased soil C levels, with the smallest sizes producing the longest‐lasting effects (150 d). Smaller residue size classes initially (30 d) immobilized more soil N compared with larger size classes; however, at 150 d, the smaller size classes had mobilized increasing amounts of N while the larger size classes had progressively immobilized more N. We conclude that crop residue management operations changed characteristic residue size distributions that moderate decomposition activities and result in unique soil C and N dynamics, possibly influencing soil properties, including nutrient availability.
Nitrogen and Harvest Management Effects on Switchgrass and Mixed Perennial Biomass Production
Authors: Sawyer Anne , Rosen Carl , Lamb John , Sheaffer Craig
Published: May 2018

Core Ideas

Switchgrass bred for energy production did not out‐perform well‐adapted switchgrass forage cultivars.

Yields from a low‐diversity grass mix were similar to those from the most productive switchgrass monocultures.

Harvest treatments were similar on loam; post‐frost yields were greater on loamy sand.

Maximum productivity was obtained with 56 kg N ha−1 yr−1 on loam and 112 kg N ha−1 on loamy sand.

Feedstocks containing annuals removed similar or greater N than grass‐only feedstocks.

Biofuel production using native perennials on marginal soils can reduce US dependence on foreign oil and curtail greenhouse gas emissions with minimal impact on food crop production. We quantified post‐establishment biomass yield and N removal as a function of harvest regime (anthesis and post‐frost) and N application rate (0, 56, and 112 kg N ha−1) at two marginal sites in Minnesota. We examined three switchgrass (Panicum virgatum L.) monocultures: ‘Shawnee’, ‘Sunburst’, and ‘Liberty’, a new bioenergy variety, and three polycultures: grass‐only, grass‐legume, and grass‐legume‐forb. On an excessively‐drained loamy sand soil, maximum productivity occurred in ‘Sunburst’ and ‘Shawnee’ switchgrass fertilized at 112 kg N ha−1 yr−1 in the post‐frost harvest regime, with 3‐yr total yields of 11.0 Mg ha−1, while ‘Liberty’ produced 7.0 Mg ha−1. On an eroded loam soil, maximum post‐frost productivity in ‘Shawnee’, ‘Sunburst’, and ‘Liberty’ was similar at 56 and 112 kg N ha−1 yr−1, with total yields of 32.6, 29.8, and 23.5 Mg ha−1, respectively. Yields of the low‐diversity (LD) grass mix were similar to ‘Shawnee’ switchgrass at both locations, indicating that an LD grass mix or well‐adapted switchgrass monoculture are likely the most productive feedstocks for this region. Most feedstocks produced similar or greater yields and removed less N in the post‐frost relative to the anthesis harvest. While producers may have flexibility in harvest timing for some feedstocks in the first few years following establishment, a post‐frost harvest regime may promote stand longevity with less N fertilizer use over time.
Nitrous Oxide and Ammonia Emissions from Cattle Excreta on Shortgrass Steppe
Authors: Nichols Kristopher L. , Del Grosso Stephen J. , Derner Justin D. , Follett Ronald F. , Archibeque Shawn L. , Delgado Jorge A. , Paustian Keith H.
Published: May 2018

Grazing cattle redistribute nitrogen (N) consumed in forage through urine and feces patches. The high concentration of N in these patches often exceeds the uptake demands of the local plant community, thereby providing ideal conditions for losses of reactive N. However, knowledge on nitrous oxide (N2O) and ammonia (NH3) emissions from excretal patches on shortgrass steppe grassland is limited. We studied the effect of cattle urine (1002 kg N ha−1) and feces (1021 kg N ha−1) patches on N2O and NH3 emissions in two sites with contrasting vegetation: (i) cool‐season (C3) ‘Bozoisky‐Select’ Russian wildrye [Psathyrostachys juncea (Fisch.) Nevski], pasture (C3Past) and (ii) C4‐dominated native shortgrass steppe rangeland (C4SS). Nitrous oxide and NH3 were measured using semi‐static and semi‐open chambers, respectively. Cumulative N2O emissions were 217 and 173% greater and cumulative volatile NH3 emissions were 339 and 157% greater on C3Past compared with C4SS from the urine and feces treatments, respectively. Nitrous oxide emission factors were 0.20 and 0.05% for urine and 0.07 and 0.03% for feces on C3Past and C4SS, respectively. Our findings suggest that using the IPCC Tier 1 default emission factor (2%, 95% CI = 0.7–6%) to estimate N2O emissions from cattle excretal patches on shortgrass steppe grassland would result in a significant overestimation for these dryland systems. Ammonia emission factors were 35 and 10% for urine and 7 and 5% for feces on C3Past and C4SS, respectively. With the exception of the urine treatment on C3Past, observed NH3 emissions were consistent with the IPCC Tier 1 default assumption that 20% (95% CI = 5–50%) of excretal N is volatilized as NH3+NOx.

Core Ideas

N2O emission factors from excreta (0.03–0.20%) were lower than the IPCC default (2%).

Substantial N2O emissions were not observed from excreta until a month after application.

NH3 emission factors from cattle excreta ranged from 5 to 30% on shortgrass steppe.

Elevated NH3 volatilization from excreta persisted 78 d after treatment application.

N2O and NH3 emissions from excreta were greater on C3 pasture compared with C4 rangeland.
Reaction of New Quality Protein Maize Genotypes toStriga asiatica
Authors: Nyakurwa Cacious Stanford , Gasura Edmore , Setimela Peter S. , Mabasa Stanford , Rugare Joyful Tatenda , Mutsvanga Simbarashe
Published: May 2018

Striga asiatica(L.) Kuntze, an obligate hemiparasite, can cause grain yield loss of 20 to 80% in cereal crops such as maize (Zea maysL.). In Sub‐Saharan Africa, maize breeding programs have focused on productivity of normal endosperm maize underStrigainfestation while neglecting quality protein maize (QPM). This study aimed at determining levels of resistance or tolerance of eight new QPM genotypes and four non‐QPM checks toStriga asiaticain the field, pot, and agar gel experiments. Under field conditions, genotypes were evaluated in three differentStriga‐endemic locations during the 2014–2015 and 2015–2016 cropping seasons using a four‐by‐three α‐lattice design with three replications. In the pot experiment, genotypes were arranged in 12 × 2 factorial treatments in a six‐by‐four α‐lattice design replicated four times. In the agar gel experiment, genotypes were arranged in a randomized complete block design replicated four times. In the field experiment, genotype × environment interaction was significant (p< 0.001) for grain yield, and MQ623, SC643, SC527, and SC535 were high yielding and more stable than non‐QPM genotypes. In the pot experiment, these genotypes also exhibited desirableStrigatolerance, whereas variation was significant (p< 0.05) forStrigatreatments and genotype main effects, as well as forStriga× genotype interaction for root biomass and root/shoot biomass ratio. Five QPM genotypes (MH1416, MQ623, SC643, SC527, and SC535) produced higher and more stable grain yields than most of the non‐QPM checks inStriga‐infested fields. These genotypes provided alternative QPM sources that can perform relatively well inStriga‐endemic areas.
Karyotype Stability and Genome‐Specific Nucleolar Dominance in Peanut, Its Wild 4× Ancestor, and a Synthetic AABB Polyploid
Authors: Seijo José Guillermo , Kovalsky Evelin Ivana , Chalup Laura María Isabel , Samoluk Sergio Sebastián , Fávero Alessandra , Robledo Germán Ariel
Published: May 2018

Allopolyploidy is a significant evolutionary process involved in the origin of many crops, including peanut (Arachis hypogaeaL.). The process usually results in a series of chromosome, genomic and epigenetic rearrangements in the derived polyploids. Here, we examined the chromosomal consequences undergone by AABB tetraploids ofArachisafter the genome merger. For that objective, different chromosome markers and DNA contents were compared among peanut, its wild tetraploid ancestor, and the diploid genome donorsA. duranensisKrapov. & W.C. Gregory (AA, female) andA. ipaënsisKrapov. & W.C. Gregory (BB, male). The analysis also included an artificially synthesized allotetraploid usingA. ipaënsisas a female [(A. ipaënsis×A. duranensis)4×]. The karyotypes in the natural (originated ~10,000 yr ago) and newly synthesized allopolyploids have largely maintained the patterns of heterochromatin and ribosomal RNA loci detected in the diploid progenitors. Intergenomic translocations were not evident using genome in situ hybridization, and the DNA contents of the allotetraploids corresponded to the expected sum of those observed in their parental species. The analysis of ribosomal DNA loci and their association with nucleolar organizing regions revealed a rapid establishment of nucleolar dominance in favor of the A genome. The large macrostructural stability of karyotype observed here after polyploidization has not been frequently cited for polyploid crop plants. This stability is significant for peanut breeding, since it suggests that effective introgression of wild useful alleles into cultivated peanut may potentially occur in most of the extension of the A and B chromosome complements.
Predicting the Campbell Soil Water Retention Function: Comparing Visible–Near‐Infrared Spectroscopy with Classical Pedotransfer Function
Authors: Pittaki-Chrysodonta Zampela , Moldrup Per , Knadel Maria , Iversen Bo V. , Hermansen Cecilie , Greve Mogens H. , de Jonge Lis Wollesen
Published: May 2018

Core Ideas

The Campbell model was anchored at a soil water content of −1000 cm H2O matric potential.

The two model parameters were predicted using either soil fines or vis–NIR spectroscopy.

Both methods accurately predicted the soil water retention curve.

The soil water retention curve (SWRC) is essential for the modeling of water flow and chemical transport in the vadose zone. The Campbell function and its b (pore‐size distribution index) parameter fitted to measured data is a simple method to quantify retention under relatively moist conditions. Measuring soil water retention is time consuming, and a method to accurately predict the Campbell relation from either typically available soil parameters such as bulk density, clay‐size fraction, and organic matter content (soil fines) or from visible–near‐infrared (vis–NIR) spectroscopy may provide a fast and inexpensive alternative. However, the traditional Campbell model has a reference point at saturated water content, and this soil‐structure‐dependent water content will typically be poorly related to basic texture properties and thus be poorly predicted from vis–NIR spectra. In this study, we anchor the Campbell model at the water content at −1000 cm H2O matric potential [log(1000)= pF 3]. Agricultural soil samples with a wide textural range from across Denmark were used. Soil water retention was measured at a number of matric potentials between pF 1 and 3. The soil water content at pF 3 and Campbell b were both well predicted using either a soil‐fines‐based pedotransfer function or vis–NIR spectroscopy. The resulting Campbell function anchored at pF 3 compared closely to measured water retention data for a majority of soils. The ability of the two methods to also predict field average SWRC was evaluated for three fields. Field average, predicted SWRC compared well with field average measured data, with vis–NIR overall performing better.
Finger Flow Development in Layered Water‐Repellent Soils
Authors: Wang Yichen , Li Yi , Wang Xiaofang , Chau Henry Wai
Published: May 2018

Core Ideas

The texture of the top layer controlled infiltration more than that of the sublayer.

Finger flow was more uniform in soils with gravel but irregular in layered water‐repellent soils.

Changes in cumulative infiltration and finger length were well correlated width wetting area.

Finger flow in water‐repellent (WR) soils significantly influences the transport of water and solutes in the soil, but the mechanics of finger flow occurrence in layered WR soils is not clear. Soil chamber infiltration experiments with a total of 20 treatments, including five different WR levels with four layer combinations, i.e., clay or sandy loam overlying sand or heavy gravel, were conducted to reveal the mechanics of finger flow occurrence in layered WR soils. The variations of the finger flow dynamics and infiltration parameters were investigated. The results showed: (i) the temporal variations of cumulative infiltration (CI) decreased with the increase of the WR level so that CI was generally larger when the top layer was sandy loam rather than clay loam and therefore the top layer soil texture controlled CI more than the sublayer; (ii) for the wettable treatments, finger flow was clearly and uniformly generated in layered soils with a sublayer of heavy gravel rather than sand, but for WR layered treatments, fingers developed irregularly with the WR levels and finger length, width, and velocity varied with the WR levels; (iii) there were good power function or linear correlations between CI and cumulative wetting area, and between CI and finger length; and (iv) water content in the top layer was higher than in the sublayer and generally decreased with the increase of WR level. Finger flow development in layered WR soils was generally irregular and showed a large degree of complexity.
Field and Laboratory Evaluation of the CS655 Soil Water Content Sensor
Authors: Caldwell Todd G. , Bongiovanni Tara , Cosh Michael H. , Halley Chelsea , Young Michael H.
Published: May 2018

Core Ideas

The CS655 measures two‐way travel time and attenuation of a low‐frequency EM pulse to derive Ka, EC, and SWC.

Laboratory and field evaluations for five central Texas soils found the sensor robust but RMSE could be reduced by a soil‐ or site‐specific function.

The factory calibration has a cross‐over point at Ka ∼15, with low bias below and high bias above.

The TxSON network mean was unaffected by calibration but the variance was significantly reduced.

Soil moisture sensors infer volumetric soil water content (SWC) from other properties of the bulk porous media. The CS655 water content reflectometer is a relatively new, low‐frequency electromagnetic sensor that determines relative permittivity (Ka) using the two‐way travel period and voltage attenuation of the applied signal along two 12‐cm rods. This measured attenuation is quadratically related to bulk electrical conductivity (EC). Along with an onboard thermistor, the CS655 allows a more robust correction of propagation time and Ka, which its predecessors, the CS615 and CS616, lacked. However, with new sensors it is necessary to quantify their practical accuracy in the field. Here, we present an overview of the CS655 sensor and an evaluation under both laboratory and field conditions, using five surface soils (0–10‐cm depth) in the laboratory and gravimetric samples collected in the field. Overall, a site‐specific calibration using a two‐term linearization of the SWC–Ka function reduced the root mean square error (RMSE) of the factory‐derived SWC of 0.073 and 0.043 m3 m−3 during batch and infiltration experiments, respectively, to 0.025 and 0.028 m3 m−3. Results further indicate that a soil‐specific calibration additionally reduced the RMSE to <0.02 m3 m−3. Field evaluation across the Texas Soil Observation Network found that calibration reduced the variance across the network but did not affect the arithmetic mean or the RMSE against gravimetric sampling, which remained ∼0.05 m3 m−3 regardless of the SWC–Ka–EC function applied. At the regional scale, a global calibration is sufficient.
Noninvasive Imaging of Processes in Natural Porous Media: From Pore to Field Scale
Authors: Pohlmeier Andreas , Garré Sarah , Roose Tiina
Published: May 2018

Core Ideas

Noninvasive, high‐resolution imaging is important for visualizing water flow and transport processes.

Most important are X‐ray CT, MRI, and neutron CT.

Image processing techniques are mandatory for maximum benefit from the images.

Noninvasive, high‐resolution imaging techniques are important for visualizing water flow and transport processes in soils, which are natural porous media. They are a key to understanding effects such as crop production, water resource restoration, CO2sequestration, or the transport and fate of pollutants. During the last two decades, the development of three‐dimensional imaging techniques such as nuclear magnetic resonance imaging (NMR and MRI), X‐ray computed tomography (CT), and neutron CT has made significant progress possible in the study of soil processes. This special section presents examples of X‐ray CT and NMR from the small‐column scale to the application of portable NMR equipment in the field, along with some important advances in image processing that make it possible to extract optimal physical information from the original data.