bluuebunny/crossref_metadata_2025 huggingface dataset:
White Matter Integrity Pre- and Post Marijuana and Alcohol Initiation in Adolescence
Authors: Jacobus Joanna , Squeglia Lindsay , Infante M. , Bava Sunita , Tapert Susan
Published: March 2013

Characterizing the effects of alcohol and marijuana use on adolescent brain development is important for understanding potential alterations in neurodevelopment. Several cross sectional studies have identified group differences in white matter integrity after initiation of heavy alcohol and marijuana use, however none have explored white matter trajectories in adolescents pre- and post initiation of use, particularly for marijuana users. This study followed 16 adolescents with minimal alcohol and marijuana use at ages 16–18 over three years. At follow-up, teens were 19–22 years old; half of the participants initiated heavy alcohol use and half initiated heavy alcohol and marijuana use. Repeated-measures ANOVA revealed 20 clusters in association and projection fibers tracts (p < 0.01) in which a group by time interaction was found. Most consistently, white matter integrity (i.e., fractional anisotropy) decreased for those who initiated both heavy alcohol and marijuana use over the follow-up interval. No effect of time or change in white matter integrity was seen for those who initiated alcohol use only in the majority of clusters. In most regions, at the baseline time point, teens who would later initiate both alcohol and marijuana use demonstrated white matter integrity greater than or equal to teens that initiated alcohol use only. Findings suggest poorer tissue integrity associated with combined initiation of heavy alcohol and marijuana use in late adolescence. While pre-existing differences may also be related to likelihood of substance use, the present data suggest an effect on tissue integrity for these teens transitioning to combined alcohol and marijuana use in later adolescence.
Holographic Dark Information Energy: Predicted Dark Energy Measurement
Authors: Gough Michael
Published: March 2013

Several models have been proposed to explain the dark energy that is causing universe expansion to accelerate. Here the acceleration predicted by the Holographic Dark Information Energy (HDIE) model is compared to the acceleration that would be produced by a cosmological constant. While identical to a cosmological constant at low redshifts, z < 1, the HDIE model results in smaller Hubble parameter values at higher redshifts, z > 1, reaching a maximum difference of 2.6 ± 0.5% around z ~ 1.7. The next generation of dark energy measurements, both those scheduled to be made in space (ESA’s Euclid and NASA’s WFIRST missions) and those to be made on the ground (BigBOSS, LSST and Dark Energy Survey), should be capable of determining whether such a difference exists or not. In addition a computer simulation thought experiment is used to show that the algorithmic entropy of the universe always increases because the extra states produced by the accelerating expansion compensate for the loss of entropy from star formation.
Spatial Characterization of Wildfire Orientation Patterns in California
Authors: Barros Ana , Pereira José , Moritz Max , Stephens Scott
Published: March 2013

Using 100 years of fire perimeter maps, we investigate the existence of geographical patterns in fire orientation across California. We computed fire perimeter orientation, at the watershed level, using principal component analysis. Circular statistics were used to test for the existence of preferential fire perimeter orientations. Where perimeters displayed preferential orientation, we searched for evidence of orographic channeling by comparing mean fire orientation with watershed orientation. Results show that in California, 49% of the burnt area is associated with watersheds, where fires displayed preferential orientation. From these, 25% of the burnt area is aligned along the NE/SW orientation and 18% in the E/W orientation. In 27 out of 86 watersheds with preferential fire alignment, there is also correspondence between mean fire orientation and watershed orientation. Topographic influence on fire spread and dominant wind patterns during the fire season can account for the consistency in fire perimeter orientation in these regions. Our findings highlight the historical pattern of fire perimeter orientation and identify watersheds with potential orographic channeling.
Motivators and Barriers to Incorporating Climate Change-Related Health Risks in Environmental Health Impact Assessment
Authors: Turner Lyle , Alderman Katarzyna , Connell Des , Tong Shilu
Published: March 2013

Climate change presents risks to health that must be addressed by both decision-makers and public health researchers. Within the application of Environmental Health Impact Assessment (EHIA), there have been few attempts to incorporate climate change-related health risks as an input to the framework. This study used a focus group design to examine the perceptions of government, industry and academic specialists about the suitability of assessing the health consequences of climate change within an EHIA framework. Practitioners expressed concern over a number of factors relating to the current EHIA methodology and the inclusion of climate change-related health risks. These concerns related to the broad scope of issues that would need to be considered, problems with identifying appropriate health indicators, the lack of relevant qualitative information that is currently incorporated in assessment and persistent issues surrounding stakeholder participation. It was suggested that improvements are needed in data collection processes, particularly in terms of adequate communication between environmental and health practitioners. Concerns were raised surrounding data privacy and usage, and how these could impact on the assessment process. These findings may provide guidance for government and industry bodies to improve the assessment of climate change-related health risks.
Correction: Liang, J., et al. Antisense Oligonucleotide Against Clusterin Regulates Human Hepatocellular Carcinoma Invasion Through Transcriptional Regulation of Matrix Metalloproteinase-2 and E-Cadherin. Int. J. Mol. Sci. 2012, 13, 10594-10607
Authors: Chen Dong , Wang Yan , Zhang Kejun , Jiao Xuelong , Yan Bomin , Liang Jun
Published: March 2013

The original version of the paper reports that “OGX-011 is a second generation 21-mer oligonucleotide with a 20-O-(2-methoxy)-ethyl modification, generously provided by OncoGenex Technologies (OncoGenex, Vancouver, Canada)” [1] (p. 10602). OGX-011 was not provided by OncoGenex Technologies directly. Therefore, we would like to correct the wording to: “OGX-011 was obtained without the benefit of an agreement with OncoGenex, or The University British Columbia, or any other party”. The authors would like to apologize for any inconvenience this may have caused to the readers of this journal. [...]
Identification of Amplified Fragment Length Polymorphism (AFLP) Markers Tightly Associated with Drought Stress Gene in Male Sterile and Fertile Salvia miltiorrhiza Bunge
Authors: Zhang Yuejin , Guo Lijun , Shu Zhiming , Sun Yiyue , Chen Yuanyuan , Liang Zongsuo , Guo Hongbo
Published: March 2013

Consistent grain yield in drought environment has attracted wide attention due to global climate change. However, the important drought-related traits/genes in crops have been rarely reported. Many near-isogenic lines (NILs) of male sterile and fertile Salvia miltiorrhiza have been obtained in our previous work through testcross and backcross in continuous field experiments conducted in 2006–2009. Both segregating sterile and fertile populations were subjected to bulked segregant analysis (BSA) and amplified fragment length polymorphism (AFLP) with 384 and 170 primer combinations, respectively. One out of 14 AFLP markers (E9/M3246) was identified in treated fertile population as tightly linked to the drought stress gene with a recombination frequency of 6.98% and at a distance of 7.02 cM. One of 15 other markers (E2/M5357) was identified in a treated sterile population that is closely associated with the drought stress gene. It had a recombination frequency of 4.65% and at a distance of 4.66 cM. Interestingly, the E9/M3246 fragment was found to be identical to another AFLP fragment E11/M4208 that was tightly linked to the male sterile gene of S. miltiorrhiza with 95% identity and e-value 4 × 10−93. Blastn analysis suggested that the drought stress gene sequence showed higher identity with nucleotides in Arabidopsis chromosome 1–5.
Factors Affecting the Effectiveness of Inorganic Silicate Sealer Material through Multi-Quality Characteristics
Authors: Zou Si-Yu , Huang Ran , Chi Mao-Chieh , Hsu Hui-Mi
Published: March 2013

This study investigates the effectiveness of concrete protection with two inorganic silicate sealer materials (ISSMs). The Taguchi method and grey relational analysis (GRA) have been used to identify the key factors influencing concrete protection provided by the surface treatment. Seven control factors with two levels were selected. By using the orthogonal array L12 (27), 12 experiments are chosen and four tests—the compressive strength test, resistivity test, absorption test and permeability test—were performed. Results have shown that the major factors affecting the protection effectiveness of ISSM are the water-binder ratio of mortar substrate, age of substrate for sealer application, addition of pozzolanic material and sealer type.
Exploring Polymeric Micelles for Improved Delivery of Anticancer Agents: Recent Developments in Preclinical Studies
Authors: Tan Chalet , Wang Yingzhe , Fan Wei
Published: March 2013

As versatile drug delivery systems, polymeric micelles have demonstrated particular strength in solubilizing hydrophobic anticancer drugs while eliminating the use of toxic organic solvents and surfactants. However, the true promise of polymeric micelles as drug carriers for cancer therapy resides in their potential ability to preferentially elevate drug exposure in the tumor and achieve enhanced anticancer efficacy, which still remains to be fully exploited. Here, we review various micellar constructs that exhibit the enhanced permeation and retention effect in the tumor, the targeting ligands that potentiate the anticancer efficacy of micellar drugs, and the polyplex micelle systems suitable for the delivery of plasmid DNA and small interference RNA. Together, these preclinical studies in animal models help us further explore polymeric micelles as emerging drug carriers for targeted cancer therapy.
Discovering Host Genes Involved in the Infection by the Tomato Yellow Leaf Curl Virus Complex and in the Establishment of Resistance to the Virus Using Tobacco Rattle Virus-based Post Transcriptional Gene Silencing
Authors: Czosnek Henryk , Eybishtz Assaf , Sade Dagan , Gorovits Rena , Sobol Iris , Bejarano Eduardo , Rosas-Díaz Tábata , Lozano-Durán Rosa
Published: March 2013

The development of high-throughput technologies allows for evaluating gene expression at the whole-genome level. Together with proteomic and metabolomic studies, these analyses have resulted in the identification of plant genes whose function or expression is altered as a consequence of pathogen attacks. Members of the Tomato yellow leaf curl virus (TYLCV) complex are among the most important pathogens impairing production of agricultural crops worldwide. To understand how these geminiviruses subjugate plant defenses, and to devise counter-measures, it is essential to identify the host genes affected by infection and to determine their role in susceptible and resistant plants. We have used a reverse genetics approach based on Tobacco rattle virus-induced gene silencing (TRV-VIGS) to uncover genes involved in viral infection of susceptible plants, and to identify genes underlying virus resistance. To identify host genes with a role in geminivirus infection, we have engineered a Nicotiana benthamiana line, coined 2IRGFP, which over-expresses GFP upon virus infection. With this system, we have achieved an accurate description of the dynamics of virus replication in space and time. Upon silencing selected N. benthamiana genes previously shown to be related to host response to geminivirus infection, we have identified eighteen genes involved in a wide array of cellular processes. Plant genes involved in geminivirus resistance were studied by comparing two tomato lines: one resistant (R), the other susceptible (S) to the virus. Sixty-nine genes preferentially expressed in R tomatoes were identified by screening cDNA libraries from infected and uninfected R and S genotypes. Out of the 25 genes studied so far, the silencing of five led to the total collapse of resistance, suggesting their involvement in the resistance gene network. This review of our results indicates that TRV-VIGS is an exquisite reverse genetics tool that may provide new insights into the molecular mechanisms underlying plant infection and resistance to infection by begomoviruses.
Characterization of microsatellites for the endangered Ruta oreojasme (Rutaceae) and cross‐amplification in related species
Authors: Meloni Marilena , Reid Andrea , Conti Elena
Published: March 2013

• Premise of the study: Ruta oreojasme is an endangered species endemic to Gran Canaria (Canary Islands, Spain), where it occurs in small populations with disjunct distribution. Nothing is known about the genetic structure of these populations.

• Methods and Results: Using a microsatellite‐enriched library method, 10 microsatellite markers have been developed from R. oreojasme, all of which showed polymorphism. The transferability of the 10 markers was tested in two other Canarian endemic species, R. microcarpa and R. pinnata, as well as in the widespread species R. montana.

• Conclusions: Our results demonstrate the value of these newly developed microsatellite markers to investigate the genetic structure in R. oreojasme and show their potential applicability for population genetic studies in other Ruta species.
Citrus (Rutaceae) SNP markers based on Competitive Allele‐Specific PCR; transferability across the Aurantioideae subfamily
Authors: Garcia‐Lor Andres , Ancillo Gema , Navarro Luis , Ollitrault Patrick
Published: March 2013

• Premise of the study: Single nucleotide polymorphism (SNP) markers based on Competitive Allele‐Specific PCR (KASPar) were developed from sequences of three Citrus species. Their transferability was tested in 63 Citrus genotypes and 19 relative genera of the subfamily Aurantioideae to estimate the potential of SNP markers, selected from a limited intrageneric discovery panel, for ongoing broader diversity analysis at the intra‐ and intergeneric levels and systematic germplasm bank characterization.

• Methods and Results: Forty‐two SNP markers were developed using KASPar technology. Forty‐one were successfully genotyped in all of the Citrus germplasm, where intra‐ and interspecific polymorphisms were observed. The transferability and diversity decreased with increasing taxonomic distance.

• Conclusions: SNP markers based on the KASPar method developed from sequence data of a limited intrageneric discovery panel provide a valuable molecular resource for genetic diversity analysis of germplasm within a genus and should be useful for germplasm fingerprinting at a much broader diversity level.
Macular and Retinal Nerve Fiber Layer Thickness in Unilateral Anisometropic or Strabismic Amblyopia
Authors: Andalib Dima , Javadzadeh Alireza , Nabai Reza , Amizadeh Yashar
Published: March 2013

Purpose:

To compare the macular and nerve fiber layer thicknesses as measured by optical coherence tomography (OCT) in amblyopic and fellow eyes.

Methods:

Fifty patients with monocular strabismic (n = 25) or anisometropic (n = 25) amblyopia (best corrected visual acuity (BCVA) ranging from 20/40 to 20/400) were included in a prospective cross-sectional descriptive study. A refractive error more than 5 diopters in either eye or an axial length difference between the eyes of more than 1 mm was excluded in the anisometropic group. In all cases, the thickness of the macular area and the peripapillary nerve fiber layer were measured by OCT in both amblyopic and fellow eyes and compared with each other.

Results:

The mean age of patients was 10 ± 3.1 years (range: 6 to 18 years) in the anisometropic group and 8.9 ± 3.7 years (range: 6 to 18 years) in the strabismic group. In the anisometropic group, the mean macular thickness was significantly increased in the amblyopic eyes (222.6 ± 47.8 μm) versus the fellow eyes (205.6 ± 33.3 μm) (
P
= .002), although there was no significant difference observed when comparing with the prepapillary nerve fiber layer (
P
= .55). There was no significant correlation of above-mentioned matters in the strabismic group (
P
= .07 and .52).

Conclusion:

A thicker macula was found in anisometropic amblyopic eyes, but the increase of macular thickness in strabismic amblyopic eyes was not significant. Retinal involvement was not observed in the peripapillary nerve fiber layer of amblyopic eyes.

[J Pediatr Ophthalmol Strabismus 2013;50(4):218–221.]
The Cognitive Consequences of Stigma, Social Withdrawal, and Depression in Adults Aging with HIV
Authors: Vance David E.
Published: March 2013

In addition to the immune system, HIV also affects the nervous system. Even with highly active antiretroviral therapy helping reduce the impact of HIV on the body and brain, approximately 50% of individuals with HIV experience cognitive problems. As people age with HIV, there is growing concern that they will be at increased risk of developing cognitive problems that may have an impact on their everyday functioning (e.g., medication adherence) and quality of life. Unfortunately, HIV-related stigma, social withdrawal, and depression, which are common to the HIV experience, can also have direct and indirect negative consequences on cognition. Research and practice implications concerning these relationships are posited.
Evaluation of Serious Games
Authors: Göbel Stefan , Gutjahr Michael , Hardy Sandro
Published: March 2013

Comprehensive evaluation studies are necessary to “prove” the benefit of Serious Games (SG). This is also extremely important for the commercial success of SG: Best practice examples with profound, well-recorded positive effects will provide relevant arguments to invest into SG for training/education, sports and health, and other application domains. On the other hand, it is not easy to prove the benefit of SG and to measure its effects (e.g. learning effects or medical effects) and affects (user experience factors such as fun during play). Evaluation methodologies might be split into observation, self-evaluation (e.g. questionnaires, interviews), associative methods, performance analyses, and psychophysiology measurement. Technology-enhanced evaluation methods, for instance, facing expression measurement are in the centre of attention. This chapter provides an overview of these methods and describes current interdisciplinary research and technology development achievements in that field.
Quantitative Analysis of Voice and Keyboard Chat in a Paper Presentation Seminar in a Virtual World
Authors: Gutjahr Michael , Bösche Wolfgang
Published: March 2013

To investigate the possibilities that are offered to improve teaching within a virtual environment, chat recordings from a paper presentation seminar in a virtual world were analyzed. A total of 9 sessions with more than 500 minutes of recordings from 19 participants were classified in diverse categories by two independent coders. The channel used (voice or keyboard) as well as other attributes of the contributions, the contributors, and the sessions were coded. Results show that the voice channel was mainly used for relevant contributions, while the keyboard channel contained mainly irrelevant contributions. The longer a session was the lower was the percentage of irrelevant contributions, p < .05. Gender and previous experience with digital games are both highly correlated with the percentage of irrelevant contributions, p < .01. Technical and personal factors are related to the rate of irrelevant contributions, while situational and relational factors seem to have a minor impact.
Serious Games and Motor Learning
Authors: Wiemeyer Josef , Hardy Sandro
Published: March 2013

Digital games in general require fine motor skills, i.e., operating the computer mouse, the keyboard, the touch-screen, or a joystick. With the development of new gaming interfaces, the performance of whole-body movements became possible to control a game. This opens up new lines of application, e.g. improving motor skills and motor abilities. The most important question is whether and how virtual game-based perceptual-motor training transfers to real motor tasks. Theory distinguishes between specific motor skill learning and generic motor ability improvement. Existing evidence shows that the improvement of motor abilities (e.g., balance) is possible by particular exergames while the improvement of motor skills (e.g., basketball throw) depends on several moderators like accuracy of the interface and correspondence of virtual and real tasks. The authors conclude that there are two mechanisms of transfer, located at the elementary and fundamental perceptual-motor level and at the cognitive level. Current issues for technology comprise adaptivity, personalization, game mastering, accuracy of interfaces and sensors, activity recognition, and error detection.
Clinical Virtual Worlds
Authors: Heinrichs LeRoy , Fellander-Tsai Li , Davies Dick
Published: March 2013

The deployment of virtual worlds into clinical practice is gradually becoming an accepted if innovative approach. This chapter offers an overview of the application of virtual worlds in a healthcare settings with specific focus on the application of virtual worlds in clinical practice. When combined with dynamic patient data models, facilitators are able to customize and deliver real time immersive clinical training experiences in a range of contexts. Given that virtual worlds are now being implemented in some of the more complex areas of healthcare, this chapter then explores how the lessons being learnt in this context could be applied more widely to other areas of professional development in the healthcare sector and concludes that direct and valuable lessons from mainstream clinical practice with virtual worlds are ready to be applied now more widely in the healthcare sector.
Social Inclusion through Virtual Worlds
Authors: de Graaf Hein
Published: March 2013

In this chapter, the theoretical foundation of the use of virtual worlds (3D environments) to strengthen the personal social network of people who are challenged in that area, especially the elderly, is described. The psychological (bordering on sociological and anthropological) aspects of “living” in a virtual “world,” such as Second Life, are described. Opportunities and threats of those aspects regarding the possibilities of strengthening the personal network and quality of life are indicated. The chapter is based on a 5-year research project. The concrete outcome of which is translated into real life projects under the name VayaV. VayaV is described in this chapter as a case study. The Dutch municipalities all agree that the main social problems facing their citizens are exclusion, feeling lonely, passivity, and lack of friends and an adequate personal social network. In the latest figures, more than a third of the people who were interviewed (a cross section of the whole Dutch population) said: I am often lonely and I am suffering because of it. With their consent, a virtual environment is developed based on the research project in Second Life, in such a way that people who do not like computers and know nothing about digital social networks can meet and have fun and form a community of friends and acquaintances. In this case, there is more to the VayaV approach than playing a game in which someone has set the rules and goals for you. It is more like everyday life where people set their own goals and rules, according to their own values and norms.
Games in Entrepreneurship Education to Support the Crafting of an Entrepreneurial Mindset
Authors: Achtenhagen Leona , Johannisson Bengt
Published: March 2013

An increasing number of education institutions, including many universities and colleges, are offering entrepreneurship education. This development is driven by the hope that more entrepreneurs could be “created” through such efforts, and that these entrepreneurs through their newly founded ventures will contribute to economic growth and job creation. At higher education institutions, the majority of entrepreneurship courses rely on writing business plans as a main pedagogical tool for enhancing the students’ entrepreneurial capabilities. In this chapter, the authors argue instead for the need for a pedagogy that focuses on supporting students in crafting an entrepreneurial mindset as the basis for venturing activities. They discuss the potential role of games in such entrepreneurship education and present the example of an entrepreneurship game from the Swedish context, which was developed by a group of young female entrepreneurs. The authors describe the game and discuss their experiences of playing it with a group of novice entrepreneurship and management students at the master’s level, and they review the effectiveness of the game in terms of how it supports students in crafting an entrepreneurial mindset. The authors conclude the chapter by outlining how entrepreneurship games could be integrated into a university curriculum and suggest some directions for future research.
A Design Framework for Educational Exergames
Authors: Kiili Kristian , Perttula Arttu
Published: March 2013

This chapter presents a framework for understanding the elements of educational exergames that combine both cognitive and physical gameplay. The aim of the framework is to provide a foundation to develop engaging and effective educational exergames as well as to provide a blueprint to define reasonable research settings. By using the framework, designers can scrutinize their game designs, either in research or commercial settings, and reveal new ways to optimize learning effects, health effects, and user experience in educational exergames. The chapter describes a case study in which the framework was used to fine-tune an educational exergame called “Yammy Attack.” The results showed that the framework was a useful tool to imagine and discover novel design solutions that would not necessarily otherwise emerge. Furthermore, the chapter discusses the usefulness of educational exergames and possibilities to incorporate them into the schools.
The Impact of International Management on Inclusion of Persons with Disabilities in the Workforce
Authors: Mouzakitis George S. , Goutou Despoina
Published: March 2013

Managers tend to recruit individuals of highest educational standards who deserve quality jobs and attractive remuneration. Equally, disabled persons should enjoy the same benefits. In our era of unprecedented technological development, education should be flexible in order to meet the contemporary demands and the needs of all persons. This chapter analyzes the use of aids, including educational games that can be helpful in supporting people with disabilities. Types of games and games for disabled persons are considered. A more active involvement of international managers in the use of games in educational/training courses for disabled persons is also proposed. Their duties must be amended to include participation in curricula design for any level of vocational/technical education.
Enhancements to the Localized Genetic Algorithm for Large Scale Capacitated Vehicle Routing Problems
Authors: Ursani Ziauddin , Essam Daryl , Cornforth David , Stocker Robert
Published: March 2013

This paper is a continuation of two previous papers where the authors used Genetic Algorithm with automated problem decomposition strategy for small scale capacitated vehicle routing problems (CVRP) and vehicle routing problem with time windows (VRPTW). In this paper they have extended their scheme to large scale capacitated vehicle routing problems by introducing selective search version of the automated problem decomposition strategy, a faster genotype to phenotype translation scheme, and various search reduction techniques. The authors have shown that genetic algorithm used with automated problem decomposition strategy outperforms the GAs applied on the problem as a whole not only in terms of solution quality but also in terms of computational time on the large scale problems.
Parallelized ACO based Routing for Stagnation Mitigation and Avoidance of Multimedia Traffic Over MANETs
Authors: Sharma Priyanka , Kotecha K.
Published: March 2013

Ant Colony Optimization (ACO) (Deepalakshmi & Radhakrishnan, 2009; Sharma & Kotecha, 2011; Sharma, Karkhanawala, & Kotecha, 2011) is a meta-heuristic, suitable for optimized solutions to routing problem in Mobile Adhoc Networks (MANETs). ACO based algorithms are fully distributed, self-organizing, fault tolerant, and intrinsically adapts to changing traffic patterns. However, if the best path is preferred for routing over longer period of time, the exploratory behaviour of the ants may be affected, thus leading to stagnation of the best paths. The authors have reviewed various techniques used for stagnation control and avoidance (Li, Ma, & Cao, 2005). These include, Pheromone control (Schoonderwoerd, Holland, Bruten, & Rothkrantz, 1996; Wedde & Farooq, 2006; De Rango & Socievole, 2011), Pheromone heuristics control (Sim & Sun, 2003), Privileged pheromone laying (Wedde & Farooq, 2006; Stuzle & Hoos, 2000), Multiple ant colony optimization (De Rango & Socievole, 2011; Sim & Sun, 2003), and Multiple path routing (Upadhyaya & Setiya, 2009b) techniques. They also present a comparative analysis of these schemes with respect to the parameter on which they depend for stagnation avoidance. The paper also focuses on stagnation leading to losses of data, which can lay a drastic effect on the quality of multimedia transmission. The authors propose a scheme to improve the exploratory behaviour of ants, by paralleled release of two streams of forward ants in each iteration, along the path from source to destination. It is mentioned that the technique will improve the quality of multimedia routed through MANETs, due to the multipath based enhancements.
A COMPARISON OF TWO COCONUT CULTIVARS FOR HIGH PRODUCTIVITY UNDER IRRIGATION
Authors: PERIES R R A
Published: March 2013

Over four decades of research indicate that the cultivar CRIC65 is capable ofproducing a sustained higher yield compared to CRIC60 in the absence of adversesoil water deficit. Data indicate that the cumulative yield of nuts and copra are 50%higher in CRIC65 than in CRIC60 over a period of 32 years. Inadequate soil waterwould appear to be the main limiting factor to the yield production in CRIC65. Theargument is, therefore made, that if coconut is to be grown under irrigation, thecultivar CRIC65 should be selected due to its high potential productivity.
PHOTOSYNTHETIC CHARACTERISTICS AND PRODUCTIVITY OF THE COCONUT PALM
Authors: JAYASEKARA C. , NAINANAYAKE N. P. A. D. , JAYASEKARA K. S.
Published: March 2013

Among the tree crops in the tropics the coconut palm occupies an importantposition as a food, oil, and fibre crop. Productivity of crop species depends on thecombined effect of their genetic constitution, climate, nutrition and other bioticfactors. To increase the productivity of the coconut palm it is necessary to have abasic understanding of physiological processes such as assimilation of carbon andgrowth in relation to climatic factors.In-situ photosynthetic measurement of coconut seedlings using Li-COR 6500portable photosynthesis system revealed that their maximum photosynthetic capacityis attained at photosynthetic photon flux densities (PPFD) ranging from 1400-1700u moles photons m'2 S"1. The rate of apparent photosynthesis (A) of the coconutpalm varies between 2-15 a moi C02 m"2 S"1 depending on leaf age, nutritional status.and climatic factors. The rate of leaf respiration was closely similar in young andolder leaves ranging from - 2 to -1 fi mol C02m'2S"'. The measured light-useefficiency of the coconut palm was found to be 1.2 g MJ"1 and the conversionefficiency of solar energy was approximately 2.4%.Water deficit is the major constraint causing wide fluctuations in photosynthesis.Due to height of trees, the leaves in the canopy are exposed to a high wind velocityas well as water and thermal stresses. As a result, under soil water deficit conditionscoconut palms reduce excessive water loss and gaseous exchange by mid-day closureof stomata and maintain stomatal conductance at a lower level. However, the rateof apparent photosynthesis and the ratio of intercellular to ambient partial pressureof C 0 2 (P/PJ are not decreased proportionately with the stomatal conductance.
THE BROWN DWARF: A RECENT ADDITION TO THE VARIETIES AND FORMS OF THE COCONUT PALM GROWN IN SRI LANKA
Authors: PERIES R. R. A.
Published: March 2013

The endemic coconut germplasm of Sri Lanka have been categorized into threemain varieties Viz. typica, nana and aurantiaca by Liyanage (1958) based on theirmorphological characters and breeding behavior.The variety nana or the dwarf, also known as Kundira to the local farmer,included three colour forms viz. form red (Regia), form yellow (Eburnea) and formgreen (Pumilla). Except for these three colour forms no other intermediate formshad been reported.Under the germplasm collection and conservation programme of the CoconutResearch Institute of Sri Lanka, a single palm of a brown coloured dwarf wasinitially identified in a home garden near Madampe in the Puttalam district (Peries,1991). Later a few palms showing similar morphological characters and breedingbehavior were located in Kirimetiyana, Marawila and Mawathagama within thecoconut triangle, with most cases as a single tree in a home garden.The original palms were initially inspected for their breeding behavior byobserving the male and female phases of the inflorescence, and other commonmorphological characters such as stature, stem girth, presence of absence of the bole,length and width of fronds and leaflets, nut components, inflorescence and thegermination speed.The short stature (4 m), narrow stem, absence of a bole, narrow and short frondsand leaflets, the small nut size and weight and the presence of a large number offemale flowers (average 80 per inflorescence and an average of 4 per spikelet) andthe overlapping male and female phases of the inflorescence indicative of selfpollinating behavior, which are the typical characteristics of dwarfs, confirmed theidentified palm as another colour form of the variety nana. The results of the FruitComponent Analysis carried out for nuts of the original palms of the form dwarfbrown are presented in Table 1.
ASSESSMENT OE THE EFFECTS OF ENVIRONMENTAL FACTORS ON YIELD OF COCONUT (Cocos nucifera, L.)
Authors: PERIES T. S. G. , THATTIL R. O.
Published: March 2013

The long-term nut yield dataand climate data of eight variables (1976-1992) were analyzed to understand the effects of climate and weather on theyield variability between picks. The yield variation over the years had nosystematic pattern. The order of contribution of the picks to total yield is notsignificantly consistent between years. Explanatory models were developedat monthly lag periods prior to harvest of each pick. The most and leastinfluential picks in respect of climate variability are picks 5 and 2 respectively.The critical period with respect to climate and weather variability ofpicks 1 -6 are February, June, July, September, December and February respectively.The climatic models fitted at these periods explain the yield variabilitybetween picks. The influence of climatic variables during these periodsvary from pick to pick. Maximum air temperature and relative humidityin the afternoon are the two most significant environmental variables influencingyield irrespective of picks.
USE OF COIR DUST ON THE PRODUCTIVITY OF COCONUT ON SANDY SOILS
Authors: VIDHANA ARACHCHI L. P. , SOMASIRI L. L. W.
Published: March 2013

Sandy soils in the coconut triangle often impose limitations such aspoor nutrient retention and moisture availability on the growth of the coconutpalm. The physical properties of such soils has to be improved for increasingcoconut production. Incorporation of coir dust into soils, which isan organic waste of coconut fibre industry is one of the options. A series oflaboratory experiments were conducted to evaluate the capability of coirdust of different age to retain water and nutrient and to investigate the suitablemixing ratio of coir dust and soil to ameliorate the moisture status andpore size distribution of the sandy soils. Soil physical characters of coir dust/sand mixtures such as pore size distribution, capillary rise, water retentionand reduction pattern of different ratio of coir dust and soil were determined.Chemical characteristics of coir dust were also determined to study its environmentalsustainability. Chemical characteristics showed that coir dusts arepoor in nutritional value but high in nutrient retention capacity and it is highlyresistant to environmental biodegradation. The available water capacity measuredin coir dust aged from 0 to 20 years indicated that the quantity of availablewater increased from 122.7% in fresh to 222.4% in 20 years old material (g/g). The increase in available water showed a linear trend with a age ofcoir dust (r=0.913; P
MORE EVIDENCE ON THE ATTRACTION OF MALES TO THE FEMALE SEX PHERMONE OF Opisina arenosella walker
Authors: FERNANDO L. C. P. , CHANDRASIRI K. A. S.
Published: March 2013

Coconut caterpillar, {Opisina arenosella) is a serious pest causingup to about 80% yield loss in coconut in Sri Lanka (Perera, 1987). Since, it'sfirst appearance in Batticaloa district (Eastern province), around the turn ofthe century, has now spread to Western, Southern, North-Western and Central provinces. An average of 250-500 ha of coconut are being annually infested while half of that extent is subjected to treatment with insecticides.The primary reason for outbreaks is climatic conditions. The low minimumtemperatures that prevail during the October to February period is detrimental to both the pest and it's natural enemies, particularly parasitoids. At the end of the adverse period, the pest increases rapidly while the parasitoids fail to do so for another 3-4 months. This time lag causes the pest outbreak and at these pest levels, parasitoid numbers are insufficient to exert control. Therefore, if parasitoids could be augmented at the'initial stages of an infestation there are high chances of preventing onset of outbreaks. To augment laboratory- bred parasitoids it is essential to predict when and where early infestations occur since, the pattern and distribution of the infestations vary considerably each year. The presence of a female sex pheromone in coconut caterpillar, Opisina arenosella (Lepidoptera : Oecophoridae) has been revealed from studies in India (Murthy et al., 1995) and in Sri Lanka (Mumford et al., 1986). Although, some evidence was present in the preliminary studies carried outin Sri Lanka, the results were not conclusive since, there was no significantdifference in the number of male moths caught in virgin female-baited trapsand unbaited traps. However, baited traps caught more, males than females. Therefore, further studies were undertaken to ascertain the attraction of virgin females of Opisina arenosella to conspecific males. Here we present our investigations.
THE BROWN DWARF: A RECENT ADDITION TO THE VARIETIES AND FORMS OF THE COCONUT PALM GROWN IN SRI LANKA
Authors: PERERA L. , PIERIS R. R. A. , PADMASIRI M. H. L.
Published: March 2013

The endemic coconut germplasm of Sri Lanka have been; categorized into threemain varieties Viz. typica. nana and aurantiaca by Liyanage (1958) based on theirmorphological characters and breeding behavior.The variety nana or the dwarf, also known as Kundira to the local farmer,included three colour forms viz. form red (Regia), form yellow (Eburnea) and formgreen (Pumilla). Except for these three colour forms no other intermediate formshad been reported.Under the germplasm collection and conservation programme of the CoconutResearch Institute of Sri Lanka, a single palm of a brown coloured dwarf wasinitially identified in a home garden near Madampe in the Puttalam district (Peries,1991). Later a few palms showing similar morphological characters and breedingbehavior were located in Kirimetiyana, Marawila and Mawathagama within thecoconut triangle, with most cases as a single tree in a home garden.The original palms were initially inspected for their breeding behavior, byobserving the male and female phases of the inflorescence, and other commonmorphological characters such as stature, stem girth, presence of absence of the bole,length and width of fronds and leaflets, nut components, inflorescence and thegermination speed.
STEM BLEEDING INCIDENCE OF COCONUT IN HAMBANTOTA DISTRICT
Authors: Wijesekara H. R. T. , Rajapakse C. N. K. , Fernando L. C. P. , Jayasinghe C. K. , Manoher S. P. , Perera K. F. G.
Published: March 2013

A heavy incidence of stem bleeding in coconut palms was reportedduring 1995 in Hambantota District, Sri Lanka. Palm to palm survey andlaboratory investigations were conducted to determine the incidence,distribution, and cause of the epidemic. The survey revealed that 10% of thepalms in the district was affected. The stem-bleeding incidence was higher inpalms closer to water bodies and irrigation channels in the area. Theinvestigations were unable' to establish the cause of stem bleeding. Thedistribution pattern of affected palms suggests that irrigation water may causestem bleeding and predispose palms to the infection by Ganoderma sp. Thefungus Ganoderma, which causes bole and root rot disease of coconut wasconsistently isolated from the palms with fruiting bodies, and authenticity ofthe pathogen was proved by the International Mycological Institute, UK.Further studies are necessary to determine the role of water bodies inpredisposing the palms to the disease.
SOIL WATER EXTRACTION PATTERN OF COCONUT (Cocos nucifera L.) IN RELATION TO SOIL COMPACTION
Authors: VIDHANA ARACHCHI L. P. , JAPA P. A. J. , MAPA R. B. , SOMAPALA H.
Published: March 2013

Effect of soil compaction on the growth and activity of coconut (Cocosnucifera L.) roots in two soil series, namely, Andigama series (gravelly soil) andMadampe series (sandy loam soil) was studied. The effective root zone ofcoconut in relation to water absorption process under natural soil compactionwere also investigated. Soil compaction and soil moisture absorption ability wasdetermined using cone penetrometer and neutron scattering methods,respectively. Coconut root distribution in Andigama and Madampe seriesshowed that 75%-80% of roots of adult coconut palms were localised in a depthranging from 20 cm to 100 cm. About 5% of the roots were located beyond the100 cm depth and 15%-20% was confined to the top layer (0-20 cm) of soil.Root growth of coconut in the two series did not show any significantdifferences. However, the root activity in the Madampe series, with respect tomoisture absorption was higher than that of the Andigama series due to lowcompaction of the former. Results also showed that soil compaction higher than250 N/cm2 restricted the activity of coconut roots in the Andigama series formoisture absorption up to a distance of 2 m away horizontally from the base ofthe tree and the highest moisture extraction was observed at 1 m distance. Highmoisture extraction by coconut roots was confined to a depth ranging of 20 to120 cm and of 20 to 250 cm in soils of Aruligama and Madampe series,respectively, due to differences in soil compaction levels. It was concluded thatsoil compaction limits the water absorption ability of coconut roots verticallyfrom the base of the tree, rather than coconut root growth and penetration.
LOSS OF NUTRIENTS IN A HIGH YIELDING COCONUT PLANTATION THROUGH REMOVAL OF PLANT MATERIALS FROM THE FIELD
Authors: SOMASIRI L. L. W. , WIJEBANDARA D. M. D. I. , PANDITHARATHNE B. D. P , SABARATHNAM S. , KURUNDUKUMBARA C. P. A.
Published: March 2013

High yielding coconut palms absorb large quantities of nutrients from the soil. A high proportion of these nutrients are removed from the field along with the harvest and other plant components. The objective of this study was to determine the rate of macro and micro nutrient removal from the field by Typica x Typica coconut palms, yielding an average of 17,380 nuts per ha. per year, in order to assess the adequacy of the current fertilizer recommendations, to prevent a serious depletion of the nutrient reserves in the soil.Harvested nuts, fallen fronds and inflorescence parts were collected for a two-year period from September 1998 to August 2000 from 10 palms located in a "Madampe series" soil at Bandirippuwa Estate. Their nutrient content was determined by chemical analysis of samples collected from harvested nuts, fallen fronds and fallen inflorescence parts. The reserves of plant nutrients in the soil were determined by chemical analysis of representative soil samples taken from the manure circle and the centre of squares at 0-15 cm and 15-100 cm depths.The amounts of macronutrients lost through the removal of plant components from the site were 116.79 kg N, 14.02 kg P, 245.43 kg K, 40.47 kg Ca, and 33.66 kg Mg per ha. per year. In addition, removal of Na was also observed at the rate of 55.79 kg/ha. Inputs at the recommended rate (4.5 kg of Adult Palm Mixture (APM) and 1.5 kg of dolomite per palm per year) supplied 87.21 kg N, 17.07 kg P, 188.90 kg K, 104.80 kg Ca and 28.59 kg Mg per ha per year (no sodium containing fertilizers were used). The difference between the removal and input should be supplied from reserves of nutrients in the soil. The study showed that except for exchangeable potassium (363 kg/ha), the other macronutrients were present in reasonably high quantities in the experimental site. As the potassium reserves in the soil are low and fertilizer inputs supply only about 77% of the requirement of high yielding coconut (17,380 nuts per ha. per year), soil potassium will deplete rapidly at the current production level. Hence, the depletion should be compensated for either by increasing the 12 quantity of chemical fertilizer or recycling organic products of the palm itself or both. The amounts of micronutrients lost were 1.14 kg Fe, 0.63 kg Mn, 0.13 kg Cu, 0.44 kg Zn and 0.26 kg B per ha. per year. The soil reserve of available iron in the site was so high that a significant depletion of Fe would take more than 300 years. However Mn, Cu and Zn depletion may need attention since reserves in the soil were not very high compared to the rate of removal.