OALib Journal期刊

ISSN: 2333-9721




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匹配条件: “ Daniel K. Dzidzienyo” ,找到相关结果约169584条。
DNA Fingerprinting and Assessment of Genetic Diversity among 22 Cowpea [Vigna unguiculata (L.) Walp] Varieties Grown in Ghana  [PDF]
Benjamin A. Danso, Daniel K. Dzidzienyo, Ruth N. A. Prempeh, Marian D. Quain
Open Access Library Journal (OALib Journal) , 2018, DOI: 10.4236/oalib.1104938
Identification of varieties based on only morphological traits is limited by the influence of environment on such morphological traits. Deoxyribonucleic acid (DNA) fingerprinting offers an efficient system of identifying varieties at the DNA level without any environmental interference. This work used 20 Simple Sequence Repeat (SSR) markers to characterise twenty-two cowpea [Vigna unguiculata (L.) Walp] varieties for the purposes of varietal protection and further assessed for genetic diversity. This study was conducted at the Biotechnology laboratory of Council for Scientific and Industrial Research-Crops Research Institute, Ghana (CSIR-CRI). The varieties were made up of 15 cultivars released by CSIR-CRI, Ghana, 5 cultivars released by CSIR-Savannah Agricultural Research Institute, Ghana (SARI), 1 advanced line, 1 landrace and 1 exotic variety. Nineteen out of the 20 SSR markers used in this study were polymorphic. These polymorphic primers generated a range of 1 to 6 alleles per primer with polymorphic information content (PIC) varying from 0.107 (SSR-6608) to 0.656 (SSR-6613). Allele frequency ranged from 0.136 (SSR- 6371) to 0.841 (SSR-6608) with mean of 0.445. With the aid of Darwin software, dissimilarity matrix and a dendrogram were generated from the molecular data to evaluate and group the varieties based on genetic resemblance. Three pairs of varieties (Agyenkwa and Adom; Hewale and Ayiyi; Zamzam and Hewale) recorded the highest genetic distance of 0.652 each. The genetic information gathered for each variety has been made available to the breeding institutions. The genetic diversity detected among the varieties fingerprinted will be helpful to plant breeders in selecting parents for future cowpea improvement programmes.
Cross-Species Gene Expression Analysis of Species Specific Differences in the Preclinical Assessment of Pharmaceutical Compounds
John Okyere, Ekow Oppon, Daniel Dzidzienyo, Lav Sharma, Graham Ball
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0096853
Abstract: Animals are frequently used as model systems for determination of safety and efficacy in pharmaceutical research and development. However, significant quantitative and qualitative differences exist between humans and the animal models used in research. This is as a result of genetic variation between human and the laboratory animal. Therefore the development of a system that would allow the assessment of all molecular differences between species after drug exposure would have a significant impact on drug evaluation for toxicity and efficacy. Here we describe a cross-species microarray methodology that identifies and selects orthologous probes after cross-species sequence comparison to develop an orthologous cross-species gene expression analysis tool. The assumptions made by the use of this orthologous gene expression strategy for cross-species extrapolation is that; conserved changes in gene expression equate to conserved pharmacodynamic endpoints. This assumption is supported by the fact that evolution and selection have maintained the structure and function of many biochemical pathways over time, resulting in the conservation of many important processes. We demonstrate this cross-species methodology by investigating species specific differences of the peroxisome proliferator-activator receptor (PPAR) α response in rat and human.
Matched Charitable Contributions: Comparative Statics and Equilibrium  [PDF]
Daniel K. Biederman
Theoretical Economics Letters (TEL) , 2013, DOI: 10.4236/tel.2013.35047
Abstract: A small optimizing agent maximizes his utility by allocating his income to private consumption and to a contribution to a particular charity. The agent’s contribution may be matched, at a particular rate, by a large agent. We provide a comprehensive comparative-statics analysis of the agent’s problem, allowing for changes in the agent’s income, the agent’s conjecture about other agents’ contributions, and the match rate. A Nash equilibrium among n such agents is shown to exist if private consumption is a normal good for all agents. The equilibrium is unique if private consumption and charitable giving are normal goods for all agents.

Rapid Deployment of Internet-Connected Environmental Monitoring Devices  [PDF]
Daniel K. Fisher
Advances in Internet of Things (AIT) , 2014, DOI: 10.4236/ait.2014.44007
Abstract: Advances in electronic sensing and monitoring systems and the growth of the communications infrastructure have enabled users to gain immediate access to information and interaction with physical devices. To facilitate the uploading, viewing, and sharing of data via the internet, while avoiding the complexities and expense of creating personal web servers, a number of service providers have created websites offering free data hosting and viewing capabilities. Simple setup and configuration routines and available application programming interfaces allow users to quickly and easily interface sensing and monitoring devices to the internet. To demonstrate the ease and feasibility of deploying internet-connected devices, an urban landscape environmental monitoring system, consisting of two wireless field sensing systems and a wireless central receiver, was developed. The field-data sensing units consisted of Arduino microcontroller platforms, sensors, and Xbee radio modems, while the receiver consisted of an Arduino microcontroller, Xbee radio, and Ethernet module connected to an internet modem. The receiver collected and stored data from the wireless transmitters, and uploaded the data to the Xively Cloud Services data hosting and sharing website. Real-time and archived sensor data were then made available for public viewing via the internet and a web browser. Data-sharing services such as Xively provide rapid and convenient means of developing internet-accessible data-collection and viewing applications, enabling enhanced access to the Internet of Things.
The Development of Services in Customer Relationship Management (CRM) Environment from ‘Technology’ Perspective  [PDF]
Gaurav K. Agrawal, Daniel Berg
Journal of Service Science and Management (JSSM) , 2009, DOI: 10.4236/jssm.2009.24052
Abstract: The service sector is receiving much deserved attention resulting from its inevitable role in a country’s economic de-velopment. Despite all the efforts gaps such as the relationship between technological advances and service development are yet to be revealed from the perspective of new applications that organizations want to develop and implement. This paper explores opportunities using a comprehensive model (and CRM, as an example) that can be used to extend the research relating service development to the technology development aspects of the market.
Open-Source Hardware Is a Low-Cost Alternative for Scientific Instrumentation and Research  [PDF]
Daniel K. Fisher, Peter J. Gould
Modern Instrumentation (MI) , 2012, DOI: 10.4236/mi.2012.12002
Abstract: Scientific research requires the collection of data in order to study, monitor, analyze, describe, or understand a particular process or event. Data collection efforts are often a compromise: manual measurements can be time-consuming and labor-intensive, resulting in data being collected at a low frequency, while automating the data-collection process can reduce labor requirements and increase the frequency of measurements, but at the cost of added expense of electronic data-collecting instrumentation. Rapid advances in electronic technologies have resulted in a variety of new and inexpensive sensing, monitoring, and control capabilities which offer opportunities for implementation in agricultural and natural-resource research applications. An Open Source Hardware project called Arduino consists of a programmable microcontroller development platform, expansion capability through add-on boards, and a programming development environment for creating custom microcontroller software. All circuit-board and electronic component specifications, as well as the programming software, are open-source and freely available for anyone to use or modify. Inexpensive sensors and the Arduino development platform were used to develop several inexpensive, automated sensing and datalogging systems for use in agricultural and natural-resources related research projects. Systems were developed and implemented to monitor soil-moisture status of field crops for irrigation scheduling and crop-water use studies, to measure daily evaporation-pan water levels for quantifying evaporative demand, and to monitor environmental parameters under forested conditions. These studies demonstrate the usefulness of automated measurements, and offer guidance for other researchers in developing inexpensive sensing and monitoring systems to further their research.
Evaluation of alternative methods for estimating reference evapotranspiration  [PDF]
Daniel K. Fisher, H. C. Pringle III
Agricultural Sciences (AS) , 2013, DOI: 10.4236/as.2013.48A008

Evapotranspiration is an important component in water-balance and irrigation scheduling models. While the FAO-56 Penman-Monteith method has become the de facto standard for estimating reference evapotranspiration (ETo), it is a complex method requiring several weather parameters. Required weather data are oftentimes unavailable, and alternative methods must be used. Three alternative ETo methods, the FAO-56 Reduced Set, Hargreaves, and Turc methods, were evaluated for use in Mississippi, a humid region of the USA, using only measurements of air temperature. The Turc equation, developed for use with measured temperature and solar radiation, was tested with estimated radiation and found to provide better estimates of FAO-56 ETo than the other methods. Mean bias errors of 0.75, 0.28, and -0.19 mm, mean absolute errors of 0.92, 0.68, and 0.62 mm, and percent errors of 22.5%, 8.5%, and -5.7% were found for daily estimates for the FAO-56 Reduced Set, Hargreaves, and Turc methods, respectively.

Human Genetics of Diabetic Retinopathy: Current Perspectives
Daniel P. K. Ng
Journal of Ophthalmology , 2010, DOI: 10.1155/2010/172593
Abstract: Diabetic retinopathy (DR) is a most severe microvascular complication which, if left unchecked, can be sight-threatening. With the global prevalence of diabetes being relentlessly projected to rise to 438 million subjects by 2030, DR will undoubtedly pose a major public health concern. Efforts to unravel the human genetics of DR have been undertaken using the candidate gene and linkage approaches, while GWAS efforts are still lacking. Aside from evidence for a few genes including aldose reductase and vascular endothelial growth factor, the genetics of DR remain poorly elucidated. Nevertheless, the promise of impactful scientific discoveries may be realized if concerted and collaborative efforts are mounted to identify the genes for DR. Harnessing new genetic technologies and resources such as the upcoming 1000 Genomes Project will help advance this field of research, and potentially lead to a rich harvest of insights into the biological mechanisms underlying this debilitating complication.
Vliv volebních preferencí na vyvoj d věry v ústavní instituce v ase
Daniel ?ermák
St?edoevropské Politické Studie , 2010,
Abstract: Impact of Voting Preferences on the Development of Trust in Constitutional Institutions. This paper presents some findings about time-series evolution of trust in political institutions in the Czech Republic between 1997 and 2009. The analysis deals with two main issues: First, a comparison of time-series of trust in the Government of the Czech Republic, Chamber of Deputies and Senate, and second, a set of multivariate analysis. The main objective of these analyses is to find out if supporters of the incumbent party or parties are more trusting than others and whether this relationship is changing over time. The analysis employed time-series of data from regular public opinion surveys conducted by the Public Opinion Research Centre of the Institute of Sociology of the Academy of Sciences of the Czech Republic.
Návesňák Daniel
Acta Montanistica Slovaca , 1997,
Abstract: The Spi -Gemer Ore Mts. are known mainly with the abundance of ore deposits. Until present the non-ore and unconventional raw-materials has not been of the main interest. In our work some selected rock types have been tested for the use in the ceramic industry, filler industry, as an abrasive material, quartz and quartzites for the production of ferrosilicium, decorative stones and slater shales. As the most suitable for a practicable use we found the leucocratic granites with the high content of feldspars for the ceramic production, tourmaline stones as a filling into plastic material and for concrete shield, against the low-energy neutron radia-tion and the natural abrasives.

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