Journal articles: 'LD. Computers'

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Feller, Sebastian. "Recent developments in HCI." Language and Dialogue 2, no. 3 (December 14, 2012): 465–78. http://dx.doi.org/10.1075/ld.2.3.08fel.

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In this article I critically discuss four studies in the area of Human–Computer Interaction (HCI) research. The focus is on distinct dimensions of culture including both verbal and para-verbal behavior in communication. My discussion is grounded in Weigand’s (2010) theory of dialogic action games (DAG), a pragma-linguistic theory which is based on a view of language as language action. The main question is whether or not the presented research leads in a direction towards making computers believable dialog partners.

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Torgesen, Joseph K., and Theodore A. Barker. "Computers as Aids in the Prevention and Remediation of Reading Disabilities." Learning Disability Quarterly 18, no. 2 (May 1995): 76–87. http://dx.doi.org/10.2307/1511196.

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This article provides examples of ways that computer-assisted instruction can help children with learning disabilities (LD) learn to read more effectively. Computer-assisted instruction and practice in reading is fit within an instructional model for LD children that recognizes their special needs for assistance in acquiring accurate and fluent word identification skills. The theory that reading disabilities are phonologically based is discussed as a context for focusing instruction on alphabetic reading skills. Computer programs that provide training in phonological awareness, specific context-free word identification skills, and reading of connected text are described, and preliminary evidence about their instructional effectiveness is presented.

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Berninger, Virginia W., Robert D. Abbott, Amy Augsburger, and Noelia Garcia. "Comparison of Pen and Keyboard Transcription Modes in Children with and without Learning Disabilities." Learning Disability Quarterly 32, no. 3 (August 2009): 123–41. http://dx.doi.org/10.2307/27740364.

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Fourth graders with learning disabilities in transcription (handwriting and spelling), LD-TD, and without LD-TD (non-LD), were compared on three writing tasks (letters, sentences, and essays), which differed by level of language, when writing by pen and by keyboard. The two groups did not differ significantly in Verbal IQ but did in handwriting, spelling, and composing achievement. Although LD-TD and non-LD groups did not differ in total time for producing letters by pen or keyboard, both groups took longer to compose sentences and essays by keyboard than by pen. Students in both groups tended to show the same pattern of results for amount written as a larger sample of typically developing fourth graders who composed longer essays by pen. Results for that sample, which also included typically developing second and sixth graders, showed that effects of transcription mode vary with level of language and within level of language by grade level for letters and sentences. However, consistently from second to fourth to sixth grade, children wrote longer essays with faster word production rate by pen than by keyboard. In addition, fourth and sixth graders wrote more complete sentences when writing by pen than by keyboard, and this relative advantage for sentence composing in text was not affected by spelling ability. Implications of the results for using computers for accommodations or specialized instruction for students with LD-TD are discussed.

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ITO, N., and G. A. KOHRING. "CLUSTER VS. SINGLE-SPIN ALGORITHMS—WHICH ARE MORE EFFICIENT?" International Journal of Modern Physics C 05, no. 01 (February 1994): 1–14. http://dx.doi.org/10.1142/s0129183194000027.

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A comparison between single-cluster and single-spin algorithms is made for the Ising model in 2 and 3 dimensions. We compare the amount of computer time needed to achieve a given level of statistical accuracy, rather than the speed in terms of site updates per second or the dynamical critical exponents. Our main result is that the cluster algorithms become more efficient when the system size, Ld, exceeds, L~70–300 for d=2 and l~80–200 for d=3. The exact value of the crossover is dependent upon the computer being used. The lower end of the crossover range is typical of workstations while the higher end is typical of vector computers. Hence, even for workstations, the system sizes needed for efficient use of the cluster algorithm is relatively large.

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Scherer Bassani, Patrícia, Carla Reis, and Pedro Henrique Petry de Faria. "Ambientes colaborativos para a produção e o compartilhamento de atividades de aprendizagem: análise dos ambientes WebCollage, LDshake e ILDE." RENOTE 17, no. 3 (January 13, 2020): 1–10. http://dx.doi.org/10.22456/1679-1916.99232.

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Learning Design (LD) ou Design da Aprendizagem é uma área de pesquisa que tem por objetivo tornar mais explícito o processo de desenvolvimento de atividades de aprendizagem com o uso de tecnologias digitais, fomentando o uso de estratégias e de ferramentas para o registro e o compartilhamento dessas atividades. Este estudo, de abordagem qualitativa, teve como objetivo analisar ferramentas para representar e compartilhar atividades de aprendizagem. A pesquisa foi organizada em duas etapas: a) revisão de literatura, para identificar ambientes citados em artigos científicos publicados no periódico Computers & Education entre 2010-2019; b) a análise desses ambientes por meio da observação on-line. Resultados mostram que WebCollage e LDShake foram os ambientes mais citados. Entretanto, eles foram integrados a uma plataforma completa chamada Integrated Learning Design Environment (ILDE).

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Lee, Bae-Kyu. "Multi-channel LD - Driver designed for CTP(computer to plate)." Journal of the Korea Institute of Information and Communication Engineering 19, no. 3 (March 31, 2015): 667–73. http://dx.doi.org/10.6109/jkiice.2015.19.3.667.

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Bayneva, Irina I., and Nikolay E. Vorozheikin. "Features of Computer Design of LED Optical Systems." Light & Engineering, no. 03-2022 (June 2022): 69–74. http://dx.doi.org/10.33383/2022-026.

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The paper considers the problems of computer simulation of modern lighting devices (LD) based on light emitting diodes (LED) and their optical systems (OS). LED OS provides developers with sufficient opportunities to implement a variety of problems of modern lighting. In the market of competing products, it is often necessary to calculate and manufacture LED optics for specific lighting problems, the main of which is the formation of a given distribution of illuminance over the surface of an object. It is shown that the most demanded services in LED lighting engineering are the development of LED optics according to the customer’s specifications, lighting engineering testing of a modelled product, development of 3D models for further production. The main stage in the context of such design is the calculation and simulation of the OS. The results of this process are basically determined by the complex of luminous, thermal, and functional characteristics of LD. The development of modern LED LD is inseparably linked with the use of specialized software. Modern technologies and approaches, CASE-tools in the design of the LD, the main requirements for the LD models, integrated complex AllFusion Modelling Suite are considered. Functional diagrams of the process of designing the LD have been developed. 3D models of single and block lenses and reflectors of various designs have been developed in the computer-aided design system KOMPAS‑3D. For given LED properties, selected materials, and ray tracing conditions the light distribution of LED modules was obtained and analysed in TracePro software. Acceptable results have been obtained, that is why this approach can be recommended for prototyping and studying the characteristics of experimental samples of LED modules and LD.

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Li, Qin, Fu Bao Li, and Zhong Ke Li. "Study on Centering Technology of Two Large-Scale Rotating Machinery Coupling Shaft Axis." Advanced Materials Research 550-553 (July 2012): 3108–12. http://dx.doi.org/10.4028/www.scientific.net/amr.550-553.3108.

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This paper studies the centering accuracy of two large-scale rotating machinery coupling shaft. Laser LD and position sensitive sensors PSD are used to measure and adjust the centering of two shaft coupling, through the analysis of LD-double-PSD-angle prism, LD-double-PSD-plane mirror of the double LD-double-PSD, dual-LD-double PSD centering program, it established a double LD-double -PSD system mathematical model, and the computer simulations to get good results. Based on the theoretical results, the two axes large-scale rotating machinery LD-link LD-double-PSD centering system has been studied and designed.

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Lundin, Barbro. "Dialogue features in football articles over a period of fifty years." Language and Dialogue 3, no. 3 (November 22, 2013): 403–21. http://dx.doi.org/10.1075/ld.3.3.04lun.

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In this diachronic study of dialogic features in football, articles from three different sports events have been focused: The World Cups 1958, 1974 and the Euro Cup 2004. This period of almost 50 years distinguishes itself as a time period when new channels for communication have emerged: television, Internet, computer-mediated communication. This has made it possible to bridge the gulf between the communicators. Dialogue features such as questions, directives, addressing the readers with you (second person singular) and using an inclusive we are numerous in the football articles studied. The articles show an increasing tendency to address the readers with you in the articles from Euro 2004. Moreover, the sports writers refer to given responses from readers in the articles from 2004.

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Loughlin, J. F., P. M. Krijnen, G. Jablonsky, F. Y. Leung, and A. R. Henderson. "Diagnostic efficiency of four lactate dehydrogenase isoenzyme-1 ratios in serum after myocardial infarction." Clinical Chemistry 34, no. 10 (October 1, 1988): 1960–65. http://dx.doi.org/10.1093/clinchem/34.10.1960.

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Abstract We compared the diagnostic efficacy of the ratios LD-1/LD-2, LD-1/LD-3, LD-1/LD-4, and LD-1/LD-5 in 69 documented cases of myocardial infarction. We used 149 patients with congestive heart failure and 67 patients with nonmyocardial infarct as controls. We used a computer program to produce receiver-operating characteristic curves, decision threshold plots, and likelihood ratios for these LD ratios at 6-h intervals up to 108 h after the onset of chest pain or hospital admission. All ratios in the myocardial infarction cases peaked around 36 h after the onset of chest pain, while those for the nonmyocardial and congestive cardiac failure cases did not change over the 108-h period. In all patients with infarctions, LD-1/LD-4 and LD-1/LD-5 increased by 1.7 times (when LD-1 was less than 40%) and 3.4 times (when LD-1 was greater than 40%), respectively, over control values. Optimum decision threshold values were obtained at 13-24 h (LD-1/LD-5), 31-36 h (LD-1/LD-4 and LD-1/LD-3), and 55-60 h (LD-1/LD-2) after onset of symptoms. The highest likelihood ratio was obtained with the LD-1/LD-4 ratio; therefore, we suggest that this is a better diagnostic test for myocardial infarction than LD-1/LD-2.

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Vaughn, Sharon, Jeanne Shay Schumm, and Jane Gordon. "Early Spelling Acquisition: Does Writing Really Beat the Computer?" Learning Disability Quarterly 15, no. 3 (August 1992): 223–28. http://dx.doi.org/10.2307/1510245.

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This research evaluated the efficacy of handwriting, letter tiles, and computer-based instruction on the early spelling acquisition of normal achieving (NLD) and learning disabled (LD) elementary students. The study replicated and extended the Cunningham and Stanovich (1990) study. Forty-eight primary-grade students (24 non-learning disabled; 24 learning disabled) received spelling training under three experimental conditions that involved different types of instructional activity: writing, sorting letter tiles, or typing on the computer. Results indicated no significant differences between the LD and NLD groups on words spelled correctly for any of the three conditions. Since the number of spelling words learned was low across conditions and groups, the number of correctly learned bigrams was examined. No within-group differences emerged for condition (writing, tile, computer); however, significant differences between the groups were found on number of bigrams learned for writing, tile, and computer, with the NLD group outperforming the LD group on all three conditions. Statistically significant time effects for bigrams were also noted for all three conditions. Unlike the Cunningham and Stanovich (1990) study, results did not replicate the superiority of the handwriting condition for the NLD group, nor was the handwriting condition found to be significantly more effective for the LD group.

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Keene, Sylvia, and Beth Davey. "Effects of Computer-Presented Text on LD Adolescents' Reading Behaviors." Learning Disability Quarterly 10, no. 4 (November 1987): 283–90. http://dx.doi.org/10.2307/1510602.

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This investigation assessed the effects of computer-displayed text on LD students' reading comprehension, strategic behaviors, task-completion time, and attitudes toward the reading task. Fifty-one LD high-school students were randomly assigned to read two lengthy expository passages either from a computer monitor or from a comparably formatted printed page. Subjects were encouraged to use six reading strategies as often as necessary to help them comprehend. Total time spent interacting with the passages was recorded in seconds. Subjects were then assessed on comprehension of the passage content, on their use of the six strategies, and their attitudes toward the task. They were retested on passage content one week later. Results indicated that, overall, the computer-displayed text format did not affect comprehension processing, five strategic behaviors, or time on task. However, computer use appeared to facilitate the lookback text strategy and made users' attitude toward the reading task more favorable.

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P-Ray. "Behold the Ch!Ld." Communications of the ACM 64, no. 5 (May 2021): 120. http://dx.doi.org/10.1145/3453712.

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From the intersection of computational science and technological speculation, with boundaries limited only by our ability to imagine what could be. Opportunity can come calling when you least expect it.

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Schelkopf, Stuart, Caroline Dini, Thamara Beline, Alvin G. Wee, Valentim A. R. Barão, Cortino Sukotjo, and Judy Chia-Chun Yuan. "The Effect of Smoking and Brushing on the Color Stability and Stainability of Different CAD/CAM Restorative Materials." Materials 15, no. 19 (October 5, 2022): 6901. http://dx.doi.org/10.3390/ma15196901.

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This study aimed to investigate and compare the color stability and stainability of computer-aided design/computer-aided manufacturing (CAD/CAM) restorative materials in their glazed (G) and polished (P) state when exposed to cigarette smoke, as well as after brushing. Three CAD/CAM restorative materials were investigated: lithium disilicate CAD (LD), zirconia (Zr), and Telio PMMA CAD (PMMA), according to their surface finishing and assignment to cigarette smoking exposure or soaking in the saliva (control) group. The color change (∆E) was calculated before and after the intervention performed for all specimens, using the L*a*b values to quantitatively assess the shade differences. Statistical analysis was performed using one-way repeated measures ANOVA and Bonferroni multiple comparison analysis (α = 0.05). The surface finishing did not influence the materials’ stainability. Color change was noted after smoking, LD and Zr-G and Zr-P had a comparable color change (p > 0.05), while PMMA presented lower ∆E values (p < 0.05). After brushing, all specimens had a significant color change that was high for LD-G and LD-P, and Zr-G, compared with Zr-P and PMMA (p < 0.05). In conclusion, the exposure to cigarette smoke showed that LD, Zr, and PMMA are all susceptible to staining, but brushing decreases surface staining.

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Zeng, Miao Miao. "Improving the Effectiveness of Compute-Based Educational Game with IMS Learning Design." Advanced Engineering Forum 6-7 (September 2012): 1016–21. http://dx.doi.org/10.4028/www.scientific.net/aef.6-7.1016.

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This article employed the concept of IMS learning design (LD) to realize the balance of “educational function” and “entertainment” in Computer-based educational game (CEG). A design structure of CEG based on activity theory was set up firstly, and then a method how to use LD to model each element in CEG was described, which was illustrated by an integration case as well. Finally, the conclusion that LD used as a framework of game activity design can improve the effectiveness of CEG was got.

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Miyahara, H., Y. Yamada, M. Yoshino, H. Ishikawa, and T. Hasegawa. "Computer Control of LD Converter Process With Pretreated Hot Metal." IFAC Proceedings Volumes 22, no. 11 (September 1989): 181–85. http://dx.doi.org/10.1016/s1474-6670(17)53107-9.

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Xiao, Song, Xiaoyu Chen, Ruquan Liang, and Yanna Liu. "Impact of effective injection rates on density and phase diagram at the branching point." International Journal of Modern Physics B 32, no. 26 (October 18, 2018): 1850291. http://dx.doi.org/10.1142/s0217979218502910.

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In this paper, the effects of different effective injection rates at the branching point on density profiles and phase diagram have been investigated by theoretical calculation and computer simulation. At the branching point, a single-lane is divided into two sub-lanes. The variables p and q which satisfy p+q = 1 and p [Formula: see text] q are used to describe the percent of currents which enter two sub-channels, respectively. With different effective injection rates, the phase diagram includes three regions and two transition lines. Obviously, the sub-lane 2 is always in the low-density (LD) phase because the small p leads to fewer particles moving through sub-lane 2. However, sub-lane 3 is easy in the high-density (HD) phase (namely, traffic jam) because of the large q. In addition, the current of lane 1 is often in the maximal current (MC) when entrance rate [Formula: see text] [Formula: see text] 0.5. With the increase of variable q, the regions of LD/LD/LD and MC/LD/LD phases shrink dramatically while the region of the HD/LD/HD phase only expands. This result implies that the changes of the phase diagram are determined by the variable q, meanwhile, the large q will likely lead to traffic congestion.

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Hassanzadeh, Mohammad, Elahe Saffari, and Saeed Rezaei. "The impact of computer-aided concept mapping on EFL learners’ lexical diversity: A process writing experiment." ReCALL 33, no. 3 (April 15, 2021): 214–28. http://dx.doi.org/10.1017/s095834402100001x.

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AbstractNowadays, many second/foreign language (L2) academic writing instruction programs place a high premium on pre-writing strategies. The current study examined the effect of software-supported concept mapping on lexical diversity (LD) of English learners’ argumentative essays within a process writing framework. Additionally, the relationship between the learners’ LD and their overall writing quality was investigated. To this end, 53 university English as a foreign language (EFL) undergraduates were assigned to a computer-aided concept mapping (CACM) and a traditional outlining condition over a span of seven weeks. The CACM group was instructed through the graphic organizer software Inspiration®, whereas the comparison group underwent outlining instruction for planning their writing tasks. Measure of textual lexical diversity (MTLD) was used to assess the so-called D values of the assignments. The results revealed that the CACM group outperformed the outlining group in terms of LD scores. Also, no relationship was found between LD and overall quality of the essays. The findings provide L2 researchers and teachers with insights into understanding the use of CACM strategy in process writing. Moreover, exploiting MTLD afforded our experiment the opportunity to counteract potential pitfalls associated with text size. Further implications for the L2 teacher are also discussed.

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Stoiljkovic, Dragoslav, Radmila Radicevic, and Milovan Jankovic. "Dependence of the structural parameters and properties of low density polyethylene on the synthesis conditions." Journal of the Serbian Chemical Society 64, no. 10 (1999): 577–87. http://dx.doi.org/10.2298/jsc9910577s.

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In a previous publicaitons from the authors.laboratotry a method was developed to predict the structure and properties of low density polyethylene (PE-LD) that could be obtained over a very wide range of polymerization conditions. The method was proved using experimental data from the literature. However, some shortcomings of the method were noticed. The aim of this work was to overcome the shortcomings and to enable the better manipulation of experimental data using a computer. A computer program has been developed to establish the mathematical relationships between ethylene entropy and the structural parameters and density of Pe-LD. All available experimental data (more than 300 experimental points) have elaborated and confirmed our mathematical models and our theoretical predictions.

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Waluyo, Sugeng. "DEVELOPMENT OF OPEN SOURCE FINITE ELEMENT SOLVER “LD-FEM’ FOR MODELING AND SIMULATION OF RUBBER MATERIALS." ROTASI 16, no. 3 (July 1, 2014): 10. http://dx.doi.org/10.14710/rotasi.16.3.10-16.

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“LD-FEM” is an open source computer program working on the basis of finite element method (FEM) which is aimed to model and simulate large deformation in rubber materials. The kinematics of large deformation on the basis of the Total Lagrange framework is applied to linear 4-nodes tetrahedral element and then solved with Newton-Raphson iterative scheme. Furthermore, to obtain the material tangent stiffness directly from strain energy density functions, the Gill-Murray theory of numerical second derivative is used in LD-FEM. Finally, by using the Mooney-Rivlin strain energy function, the performance of LD-FEM is addressed for uniaxial tensile, shear and torsion loading tests. The results confirm the capability of LD-FEM to capture nonlinear behavior of the large deformation either with analytical or numerical approach on the material stiffness derivation with error less than 2%.

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Mallya, J., N. DuVall, J. Brewster, and H. Roberts. "Endodontic Access Effect on Full Contour Zirconia and Lithium Disilicate Failure Resistance." Operative Dentistry 45, no. 3 (May 1, 2020): 276–85. http://dx.doi.org/10.2341/18-231-l.

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SUMMARY Objectives: To evaluate the effect of endodontic access on the failure load resistance of both adhesively and conventionally luted, full-contour monolithic yttria-stabilized zirconium dioxide (Y-TZP) and adhesively luted lithium disilicate (LD) crowns cemented on prepared teeth. Methods and Materials: Seventy-two human maxillary molars were prepared per respective guidelines for all-ceramic crowns with one group (n=24) restored with LD and the other (n=48) receiving Y-TZP crowns. Preparations were scanned using computer-aided design/computer-aided milling (CAD/CAM) technology, and milled crowns were sintered following manufacturer recommendations. All LD crowns and half (n=24) of the Y-TZP crowns were adhesively cemented, while the remaining Y-TZP specimens were luted using a conventional glass ionomer cement (GIC). One LD group, one Y-TZP adhesive group, and one GIC-luted group (all n=12) then received endodontic access preparations by a board-certified endodontist: the pulp chambers were restored with a dual-cure, two-step, self-etch adhesive and a dual-cure resin composite core material. The access preparations were restored using a nano-hybrid resin composite after appropriate ceramic margin surface preparation. After 24 hours, all specimens were loaded axially until failure; mean failure loads were analyzed using Mann-Whitney U test (α=0.05) Results: Endodontic access did not significantly reduce the failure load of adhesively luted LD or Y-TZP crowns, but Y-TZP crowns with GIC cementation demonstrated significantly less failure load. Conclusions: These initial findings suggest that endodontic access preparation may not significantly affect failure load resistance of adhesively luted Y-TZP and LD crowns. Definitive recommendations cannot be proposed until fatigue testing and coronal seal evaluations have been accomplished.

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Georgieva, A. N., P. A. Bayrov, I. N. Ivanchev, M. S. Gerasimova, and S. R. Simeonov. "Distributed Computer System for Adaptive Control of LD Convertor Steel Making." IFAC Proceedings Volumes 21, no. 19 (June 1988): 299–302. http://dx.doi.org/10.1016/s1474-6670(17)54509-7.

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Banerjee, R. N., and A. Bujosa. "A geometric interpretation of LD-resolution." Theoretical Computer Science 318, no. 3 (June 2004): 435–70. http://dx.doi.org/10.1016/j.tcs.2004.03.007.

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Calver, MC, JC Mcilroy, DR King, JS Bradley, and JL Gardner. "Assessment of an Approximate Lethal Dose Technique for Determining the Relative Susceptibility of Non-Target Species to 1080-Toxin." Wildlife Research 16, no. 1 (1989): 33. http://dx.doi.org/10.1071/wr9890033.

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The susceptibility of eight species of dasyurid marsupials and five species of murid rodents from the pastoral areas of Western Australia to the toxin sodium monofluoroacetate (Compound 1080) was assessed. Both LD*5O tests and an increasing dose procedure to determine the approximate lethal dose (ALD) were used. The results ranged from a low ALD of 1.6 mg kg-1 for an island population of Pseudomys hermannsburgensis to a high of 20 mg kg-1 for a mainland population of Notomys mitchelli. Intraspecific and regional variation in sensitivity was evident: three populations of P. hermannsburgensis showed widely different ALDS, and high ALDS were found in the Millstream area relative to elsewhere in the pastoral regions. Where both ALD and LD*5O were available, the dose response curve was steep; all LDSOS were less than a factor of 1.5 above the ALD. LD*5O values and ALDS were significantly correlated for selected dasyurids and murids, using published data. A computer simulation based on sampling a standard number of animals from 10 theoretical populations differing only in their LD~O confirmed that ALD and LD*5O gave similar rankings of sensitivity, although high variance on the LD~O reduced the strength of the correlation. Actual dosing data from eight populations of Rattus fuscipes were also analysed; both LD*5O and ALD gave similar rankings of population sensitivity. Subject to assumptions about the variability of sensitivity within a population, the ALD offers an alternative to LD~O testing that requires fewer animals, and need not cause more than one death per population tested.

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Chiang, Berttram. "Initial Learning and Transfer Effects of Microcomputer Drills on LD Students' Multiplication Skills." Learning Disability Quarterly 9, no. 2 (May 1986): 118–23. http://dx.doi.org/10.2307/1510360.

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Although application of microcomputer-assisted instruction with learning disabled students is rapidly expanding, only limited research is available on the efficacy of such instruction. The primary purpose of this single-subject design study was to investigate whether learning of multiplication tables via computer programs transfers to paper-and-pencil tasks. Three male and three female fourth-grade LD students participated in the three phases of the study: baseline, microcomputer-assisted instruction, and transfer. Results of the daily 4-minute timings of each subject's multiplication facts indicated that about 12 days' drill and practice on a computer yielded an average gain of 4.7 and 6.1 facts per minute for the girls and boys, respectively, as evidenced by their worksheet performance. Implications for using microcomputer-assisted instruction with LD students are discussed.

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Vigliecca, Nora Silvana, and Javier Alfredo Voos. "Remembering a name: Neuropsychological validity studies and a computer proposal for detection of anomia." Dementia & Neuropsychologia 13, no. 4 (December 2019): 450–62. http://dx.doi.org/10.1590/1980-57642018dn13-040013.

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ABSTRACT There are contradictory results or lack of validity studies concerning the naming function and brain laterality. Although anomia is a frequent symptom of memory impairment, and the most relevant symptom of aphasia, few studies have been conducted to evaluate its validity for detecting patients with left-hemisphere damage (LD), as per the MeSH definition. Objective: To validate a paper-and-pencil confrontation naming test (CNT) according to side of brain injury; to select a valid and reliable abbreviated CNT wherein the effect of demographic variables is minimized; and to use the selected CNT to develop a computer-aided confrontation-naming evaluation (CACNE). Methods: Control data were obtained from 213 healthy participants (HP) aged 15 to 89 years. A subsample of 106 HP was demographically matched to 39 patients with LD and 40 patients with right-hemisphere damage (RD). Anomia definition and CNT cues were considered for the CACNE. Results: Test-retest and inter-rater reliability, internal consistency, and validity for detecting LD were demonstrated. A significant age effect was observed in HP. The CACNE was developed to detect anomia in interaction with environmental interventions. Conclusion: The inconsistencies observed in the CNT studies were probably due to the presence of anomia in almost 50% of the RD patients.

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Griffiths, Dai. "The Use of Models in Learning Design and Learning Analytics." Interaction Design and Architecture(s), no. 33 (June 20, 2017): 113–33. http://dx.doi.org/10.55612/s-5002-033-006.

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The practice of Learning Design (LD) and Learning Analytics (LA) is analysed using two lenses. Firstly, it is argued that both LD and LA involve the making of models. All models involve idealisation, i.e. the simplification of something complicated to make it more tractable. Various educational actors generate idealisations of the system they are working in, but only a subset of these idealisations is embodied in LD and LA implementations. Secondly, LD and LA both change the way that the actors in education handle the complexity which they are faced with in their practice. This is analysed in terms of the cybernetic concepts of variety and black boxes. It is then argued that LD and LA implementations share a tendency to shift control to higher levels in the hierarchy, and that this has consequences for the autonomy of teachers and learners, and for the acceptability to users of LD and LA. Finally, some conclusions are offered which can help LD and LA to be implemented while addressing the common problems that have been identified.

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Maccini, Paula, Joseph Calvin Gagnon, and Charles A. Hughes. "Technology-Based Practices for Secondary Students with Learning Disabilities." Learning Disability Quarterly 25, no. 4 (November 2002): 247–61. http://dx.doi.org/10.2307/1511356.

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The researchers conducted a comprehensive review of the literature on technology-based practices for secondary students identified as having learning disabilities (LD) involving instruction and/or assessment that measured some aspect of performance on a general education task or expectation (i.e., test). Technology-based practices included computer- or video-based interventions, multimedia programs, technology-based assessment, and verbatim audio recordings. Three practices appear promising for educating students with LD: (a) hypertext and hypermedia software programs; (b) videodisc instruction involving contextualized learning; and (c) multimedia software. Educational recommendations and directions for future research are offered based upon results.

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Komamizu, Takahiro, Toshiyuki Amagasa, and Hiroyuki Kitagawa. "H-SPOOL." International Journal of Web Information Systems 12, no. 3 (August 15, 2016): 359–78. http://dx.doi.org/10.1108/ijwis-03-2016-0014.

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Purpose Linked data (LD) has promoted publishing information, and links published information. There are increasing number of LD datasets containing numerical data such as statistics. For this reason, analyzing numerical facts on LD has attracted attentions from diverse domains. This paper aims to support analytical processing for LD data. Design/methodology/approach This paper proposes a framework called H-SPOOL which provides series of SPARQL (SPARQL Protocol and RDF Query Language) queries extracting objects and attributes from LD data sets, converts them into star/snowflake schemas and materializes relevant triples as fact and dimension tables for online analytical processing (OLAP). Findings The applicability of H-SPOOL is evaluated using exiting LD data sets on the Web, and H-SPOOL successfully processes the LD data sets to ETL (Extract, Transform, and Load) for OLAP. Besides, experiments show that H-SPOOL reduces the number of downloaded triples comparing with existing approach. Originality/value H-SPOOL is the first work for extracting OLAP-related information from SPARQL endpoints, and H-SPOOL drastically reduces the amount of downloaded triples.

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Thorpe, Harold, Berttram Chiang, and Margaret Lubke. "A Comparison of LD and Non-LD Students' Learning LOGO and On-Task Behavior." Computers in the Schools 3, no. 3-4 (February 2, 1987): 63–70. http://dx.doi.org/10.1300/j025v03n03_06.

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Billingsley, Glenna M., Cathy N. Thomas, and Jo A. Webber. "Effects of Student Choice of Instructional Method on the Learning Outcomes of Students With Comorbid Learning and Emotional/Behavioral Disabilities." Learning Disability Quarterly 41, no. 4 (April 18, 2018): 213–26. http://dx.doi.org/10.1177/0731948718768512.

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The purpose of this exploratory study was to determine whether learning preferences of secondary students identified with concomitant learning disabilities (LD) and emotional disturbance (ED) align with the instructional method with which they best learned mathematics. Responses to a preference survey given before and after instruction were compared with learning outcomes in a single-subject, alternating treatments research design investigating the effects of direct teach, computer-assisted instruction (CAI), and a combination of both methods. Results showed that most students were able to predict, by choice or stated preference, conditions under which they will learn best and, in hindsight, indicate the condition that provided the best learning outcome. This small study contributes to the literature on secondary mathematics learning for students with LD, and makes unique contributions regarding (a) the learning of students with comorbid LD and ED and (b) implementation of instruction that combines direct teach with CAI.

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Ciullo, Stephen, and Colleen Reutebuch. "Computer-Based Graphic Organizers for Students with LD: A Systematic Review of Literature." Learning Disabilities Research & Practice 28, no. 4 (November 2013): 196–210. http://dx.doi.org/10.1111/ldrp.12017.

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Warraich, Nosheen Fatima, and Abebe Rorissa. "Application of linked data technologies in libraries: Pakistani information professionals’ attitudes and perceptions." Electronic Library 38, no. 5/6 (November 26, 2020): 1035–51. http://dx.doi.org/10.1108/el-01-2020-0002.

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Purpose This study aims to ascertain the information professionals’ perceptions and attitudes towards the application of linked data (LD) technologies in libraries in the context of a developing country. It also explores the Pakistani information professionals’ level of familiarity with LD concepts, plans and efforts in its application, along with its potential benefits. Design/methodology/approach An online questionnaire survey was used to identify the information professionals’ perceived level of familiarity with LD concepts and benefits to implement LD in libraries, and their plans and efforts to adopt LD technologies. A questionnaire was developed to meet the objective of the study and collect data from the purposefully selected professionals (N = 86) working in university libraries in Pakistan. SPSS was used to analyse the data set. Findings Findings show that LD application in libraries is still not common among Pakistani information professionals. They have a moderate level of understanding with semantic Web (SW) and LD key concepts. The respondents were positive about the potential benefits of implementing LD technology in libraries, such as assisting patrons to discover relevant information, enriching traditional bibliographic records, enhancing the visibility and discoverability of library data and improving the users’ overall search experiences that may foster future developments. Overall, the respondents’ institutions were on different levels of planning – from working on a plan to having a finalized plan. The findings emphasized establishing the SW’s potential in library services. Research limitations/implications There are certain limitations of this study. Firstly, the population is Pakistani information professionals who are purposefully selected. Secondly, the findings reveal that the respondents’ understanding with LD concepts, opinions about LD, plans and efforts to its application along with its potential benefits in libraries are self-perceived and not tested in any way and they were not actually implementing these technologies in their institutions because of a lack of best practices. It is a quantitative study and it will serve as a baseline study, even though there is a need to conduct more in-depth qualitative studies in the information environment to explore the phenomenon. Social implications This study will guide information professionals and policymakers to take initiatives towards the implementation of LD technology in libraries. It may also lead to further research to understand the perceptions of information professionals so that appropriate training and advocacy programmes can be developed to promote LD initiatives in libraries. Originality/value To the best of the authors’ knowledge, this is the first known empirical study in the context of a developing country. It clearly demonstrates the Pakistani information professionals’ perceptions regarding the library LD and associated plans along with potential benefits to implement it.

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Solheim, J. C., B. M. Carreno, J. D. Smith, J. Gorka, N. B. Myers, Z. Wen, J. M. Martinko, D. R. Lee, and T. H. Hansen. "Binding of peptides lacking consensus anchor residue alters H-2Ld serologic recognition." Journal of Immunology 151, no. 10 (November 15, 1993): 5387–97. http://dx.doi.org/10.4049/jimmunol.151.10.5387.

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Abstract CTL recognize class I MHC/peptide complexes on the surface of target cells. Crystallographic and serologic data have indicated that peptide ligands can influence the conformation of class I molecules and hence T cell recognition. How the binding of peptides with disparate sequence motifs affects the conformation of distinct regions within a class I molecule remains unknown. A series of site-directed mutants of the murine class I molecule H-2Ld was studied to address this question. These mutants were generated by in vitro mutagenesis and used to map the serologic epitopes recognized by a panel of Ld-reactive mAb. The influence of six different ligands on serologic recognition by these mAb was then examined. Of 12 mAb tested, only one, B22/249, was found to be significantly influenced by the bound peptide. Peptide discrimination by B22/249 was observed at the cell surface and in immunoprecipitates of Ld after incubation with two of the six ligands. The two peptides that caused suboptimal B22/249 recognition of Ld/peptide lack a proline at position 2, which is present in the other four peptides and has previously been defined as an anchor residue for Ld ligands. The epitope on Ld detected by mAb B22/249 includes residues 63 to 70 on the alpha 1 domain helix. Two of these residues are in pocket B, which computer modeling predicts to be in contact with the second residue of Ld-binding peptides. Therefore, these data imply that a mAb to a class I molecule can distinguish peptides with different motifs, possibly reflecting peptide-dependent conformational changes in the class I molecule.

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Huja, S. S., E. L. Grubaugh, A. M. Rummel, H. W. Fields, and F. M. Beck. "Comparison of Hand-Traced and Computer-Based Cephalometric Superimpositions." Angle Orthodontist 79, no. 3 (May 1, 2009): 428–35. http://dx.doi.org/10.2319/052708-283.1.

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Abstract Objective: To determine the ability to produce comparable superimpositions using hand tracing and digital methods (Dolphin v10). In addition, if the two methods were comparable, we wanted to determine if a difference existed between the best-fit cranial base superimposition and S-N superimpositions using the digital method. Methods and Materials: Sixty-four initial (T1) and final (T2) cephalometric film radiographs were obtained. Cranial base and regional superimpositions were completed independently for each pair of radiographs by either hand tracing and digital methods. To quantitatively evaluate the differences between the two methods, the hand and digital superimpositions were digitized to obtain x-y coordinates of routine cephalometric landmarks at T2. Linear distance between multiple corresponding (hand and digital) T2 cephalometric landmark locations (e.g., A point) were measured and defined as the T2 landmark distance (T2 LD). Additionally, 61 patient records were used to compare the digital method for best-fit cranial base superimpositions versus S-N superimpositions. A Friedman test was applied to examine for differences. Results: The upper 95% confidence limit for the mean of the T2 LD for hand and digital superimposition methods was <1 mm for all landmarks except maxillary incisor tip and apex. The upper 95% confidence interval for best-fit vs S-N was >1 mm for most landmarks. Conclusion: This study validates the use of superimpositions produced by Dolphin Imaging version 10 and is a necessary step forward toward widespread acceptance of digital superimpositions.

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KWON, H. C. "WDM-PON Downstream Optical Link Using Wavelength-Locked FP-LD by Spectrally-Sliced FP-LD." IEICE Transactions on Communications E88-B, no. 1 (January 1, 2005): 384–87. http://dx.doi.org/10.1093/ietcom/e88-b.1.384.

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Feitosa, Danila, Diego Dermeval, Thiago Ávila, Ig Ibert Bittencourt, Bernadette Farias Lóscio, and Seiji Isotani. "A systematic review on the use of best practices for publishing linked data." Online Information Review 42, no. 1 (February 12, 2018): 107–23. http://dx.doi.org/10.1108/oir-11-2016-0322.

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Purpose Data providers have been increasingly publishing content as linked data (LD) on the Web. This process includes guidelines (i.e. good practices) to publish, share, and connect data on the Web. Several people in different areas, for instance, sciences, medicine, governments and so on, use these practices to publish data. The LD community has been proposing many practices to aid the publication of data on the Web. However, discovering these practices is a costly and time-consuming task, considering the practices that are produced by the literature. Moreover, the community still lacks a comprehensive understanding of how these practices are used for publishing LD. Thus, the purpose of this paper is to investigate and better understand how best practices support the publication of LD as well as identifying to what extent they have been applied to this field. Design/methodology/approach The authors conducted a systematic literature review to identify the primary studies that propose best practices to address the publication of LD, following a predefined review protocol. The authors then identified the motivations for recommending best practices for publishing LD and looked for evidence of the benefits of using such practices. The authors also examined the data formats and areas addressed by the studies as well as the institutions that have been publishing LD. Findings In summary, the main findings of this work are: there is empirical evidence of the benefits of using best practices for publishing LD, especially for defining standard practices, integrability and uniformity of LD; most of the studies used RDF as data format; there are many areas interested in dissemination data in a connected way; and there is a great variety of institutions that have published data on the Web. Originality/value The results presented in this systematic review can be very useful to the semantic web and LD community, since it gathers pieces of evidence from the primary studies included in the review, forming a body of knowledge regarding the use best practices for publishing LD pointing out interesting opportunities for future research.

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Ali, Irfan, and Nosheen Fatima Warraich. "Linked data initiatives in libraries and information centres: a systematic review." Electronic Library 36, no. 5 (October 1, 2018): 925–37. http://dx.doi.org/10.1108/el-04-2018-0075.

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Purpose This study aims to explore linked data (LD) initiatives in libraries and information (LI) centres along with motivating factors to start these LD projects and challenges faced by librarians in implementing LD technology. Design/methodology/approach To achieve the objectives of the study, a systematic literature review was conducted. The preferred reporting items were used for systematic review and meta-analysis (PRISMA) guideline. Data were collected from different scholarly databases. Findings Findings show that many initiatives were taken in LI centres during the past decade. These LI centres had to face many challenges to implement LD technology. These challenges might include technological issues, scarce financial resources, lack of skilled human resources, low level of awareness among community/librarians, proprietary licence, non-availability of standards and best practices. However, technological challenges were more complex. Systematic review shows that most of the LD initiatives and activities in LI centres take place in developed countries. Overall, the results reveal that most of the libraries are in the infancy stage of LD application because of the ambivalent nature of technology. Originality/value This study may be beneficial to devise guidelines to transform the aforementioned different challenges into opportunities. It is also important to provide a holistic picture about the challenges and opportunities of LD through a systematic review of initiatives already taken by LI centres.

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Huscroft-D’Angelo, Jacqueline, Kristina Higgins, and Lindy Crawford. "Communicating mathematical ideas in a digital writing environment: the impacts on mathematical reasoning for students with and without learning disabilities." Social welfare : interdisciplinary approach 4, no. 2 (December 10, 2014): 68–84. http://dx.doi.org/10.15388/sw.2014.28186.

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Mathematical reasoning is often underdeveloped in students with learning disabilities (LD). Problem solving and reasoning represent one of the most important aspects of a mathematics curriculum. The purpose of the present study was to examine how communication through writing in mathematics via a digital environment impacts the mathematical reasoning of students with and without LD. Specifically, the research was guided by research questions: (1) What differences exist between the mathematical reasoning of students with and without LD prior to and after using a digital writing environment? (2) How does use of the digital writing environment differ between students with and without LD? (3) To what extent does student reasoning change overtime when emphasis is placed on communication via writing in mathematics? Oral reading and math fact fluency as well as participants’ working memory were used as academic variables. The Math Reasoning Inventory (MRI; Burns, 2012) is a formative assessment designed to evaluate mathematical reasoning through a face-to-face interview. The primary focus is on core numerical reasoning strategies and understanding. Subjects participated in an intervention focused on communication in mathematics through the use of digital writing tools in a computer-based mathematics program. Results reveal that communication through writing or peer-based discussions around mathematics can impact students’ reasoning skills. Reasoning is a fundamental skill in mathematics and remains an area in which students with LD continuously struggle; therefore, interventions focused on advancing student reasoning will be increasingly pivotal to mathematics education. Students in this study showed improvement in different areas of reasoning over the course of the intervention and responded differently to the types of writing environments that were offered. Regardless of which digital environment was preferred by students with and without LD, results demonstrated that incorporating writing into mathematics to communicate mathematical information benefited all students in this study and has the potential to impact mathematics education.

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Salem, Amna, and Cherif Mohsen. "Atomic Force Microscope Surface Roughness Analysis of Surface Treated Ceramics." Open Access Macedonian Journal of Medical Sciences 8, no. D (August 15, 2020): 134–38. http://dx.doi.org/10.3889/oamjms.2020.4523.

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AIM: The purpose of this study was to evaluate the surface roughness of two types of ceramic after different surface treatments using an atomic force microscope (AFM). MATERIALS AND METHODS: One hundred sixty disks were fabricated of the two types of ceramic eighty disks of lithium disilicate (LD) (IPS e. max computer-aided design [CAD]) and eighty disks of hybrid ceramic (VITA Suprinity pc). Disks were subdivided into four groups according to the surface treatment (n = 20). Eighty disks of (IPS e. max CAD) were subdivided into LD I: control (no treatment), LD II: Sandblasting (Al2O3, 50 μm particle size), LD III: Hydrofluoric acid etching, and LD IV: Tribochemical surface treatment. Eighty disks of (VITA Suprinity pc) were subdivided into HD I: control (no treatment), HD II: Sandblasting (Al2O3, 50 μm particle size), HD III: Hydrofluoric acid etching, and HD IV: Tribochemical surface treatment. Then, surface treated disks surface roughness was analyzed by AFM (ThermoMicroscope, Bruker, Santa Barbara, CA, USA). The results were analyzed using SPSS program software version 25. Statistical analysis was done by one-way ANOVA and Tukey’s post hoc test with significance level 0.05. RESULTS: Tribochemical surface treatment groups of both types of ceramic L.D IV (279 ± 147 nm) and H.D IV (269.8 ± 142.2 nm) had the highest mean Ra values followed by surface abrasion with Al2O3 50 μ; L.D II (265.5 ± 140 nm), H.D II (204.5 ± 107.7 nm), hydrofluoric acid etching then control groups. CONCLUSION: Different surface treatments increased surface roughness significantly for both types of ceramic.

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Abad-Grau, M. M., R. Montes, and P. Sebastiani. "Building chromosome-wide LD maps." Bioinformatics 22, no. 16 (June 16, 2006): 1933–34. http://dx.doi.org/10.1093/bioinformatics/btl288.

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Pishtari, Gerti, María Jesús Rodríguez-Triana, and Terje Väljataga. "A Multi-Stakeholder Perspective of Analytics for Learning Design in Location-Based Learning." International Journal of Mobile and Blended Learning 13, no. 1 (January 2021): 1–17. http://dx.doi.org/10.4018/ijmbl.2021010101.

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Promoted by the growing access to mobile devices and the emphasis on situated learning, location-based tools are being used increasingly in education. Multiple stakeholders could benefit from understanding the learning and teaching processes triggered by these tools, supported by data analytics. For instance, practitioners could use analytics to monitor and regulate the implementation of their learning designs (LD), as well as to assess their impact and effectiveness. Also, the community around specific tools—such as researchers, managers of educational institutions, and developers—could use analytics to further improve the tools and better understand their adoption. This paper reports the co-design process of a location-based authoring tool that incorporates multi-stakeholder analytics for LD features. It contributes to the research community through a case study that investigates how analytics can support specific LD needs of different stakeholders of location-based tools. Results emphasise opportunities and implications of aligning analytics and LD in location-based learning.

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Kung, Woon-Man, Yao-Chin Wang, Wei-Jung Chen, and Muh-Shi Lin. "Homogeneous Chronic Subdural Hematoma with Diverse Recurrent Possibilities." Diagnostics 12, no. 11 (November 4, 2022): 2695. http://dx.doi.org/10.3390/diagnostics12112695.

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Background: Evidence suggests that hyperdense (HD) chronic subdural hematomas (CSDHs) have a higher recurrence than hypodense (LD) chronic subdural hematomas. The value of mean hematoma density (MHD) has been proven to be associated with postoperative recurrence. The MHD levels in homogeneous CSDHs likely underestimate the risk of recurrence in HD homogeneous subtypes. Methods: This study investigated 42 consecutive CSDH cases between July 2010 and July 2014. The area of the hematoma was quantified to determine the MHD level using computer-based image analysis of preoperative brain CT scans. Results: In terms of the MHD distribution of the four types of CSDHs (homogeneous, laminar, separated, and trabecular), wide 95% CI (11.80–16.88) and high standard deviation (4.59) can be found in homogeneous types, reflecting a high variability in the MHD levels between cases (from low to high density). The categorization of homogeneous types into LD and HD (type five) displayed a minor standard deviation in the MHD levels for LD and HD subtypes (1.15, and 0.88, respectively). MHD values demonstrated concentrated distributions among the respective five types, compared to the four-type setting. Conclusions: In the current research, we provide a consideration that if LD and HD hematomas are separated from homogeneous CSDHs, the variability of the MHD quantification can potentially be reduced, thereby avoiding the possibility of undetected high-risk groups.

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MENG Xiaohui, 孟晓辉, 张继友 ZHANG Jiyou, 郭文 GUO Wen, 王永刚 WANG Yonggang, and 金钊 JIN Zhao. "Study on computer modeling for collimating laser diode beam with cylindrical lens." Optical Technique 38, no. 2 (2012): 131–35. http://dx.doi.org/10.3788/gxjs20123802.0131.

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Santiago, Enrique, Irene Novo, Antonio F. Pardiñas, María Saura, Jinliang Wang, and Armando Caballero. "Recent Demographic History Inferred by High-Resolution Analysis of Linkage Disequilibrium." Molecular Biology and Evolution 37, no. 12 (July 8, 2020): 3642–53. http://dx.doi.org/10.1093/molbev/msaa169.

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Abstract Inferring changes in effective population size (Ne) in the recent past is of special interest for conservation of endangered species and for human history research. Current methods for estimating the very recent historical Ne are unable to detect complex demographic trajectories involving multiple episodes of bottlenecks, drops, and expansions. We develop a theoretical and computational framework to infer the demographic history of a population within the past 100 generations from the observed spectrum of linkage disequilibrium (LD) of pairs of loci over a wide range of recombination rates in a sample of contemporary individuals. The cumulative contributions of all of the previous generations to the observed LD are included in our model, and a genetic algorithm is used to search for the sequence of historical Ne values that best explains the observed LD spectrum. The method can be applied from large samples to samples of fewer than ten individuals using a variety of genotyping and DNA sequencing data: haploid, diploid with phased or unphased genotypes and pseudohaploid data from low-coverage sequencing. The method was tested by computer simulation for sensitivity to genotyping errors, temporal heterogeneity of samples, population admixture, and structural division into subpopulations, showing high tolerance to deviations from the assumptions of the model. Computer simulations also show that the proposed method outperforms other leading approaches when the inference concerns recent timeframes. Analysis of data from a variety of human and animal populations gave results in agreement with previous estimations by other methods or with records of historical events.

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Torgesen, Joseph K., Mary D. Waters, Andrew L. Cohen, and Jeffery L. Torgesen. "Improving Sight-Word Recognition Skills in LD Children: An Evaluation of Three Computer Program Variations." Learning Disability Quarterly 11, no. 2 (May 1988): 125–32. http://dx.doi.org/10.2307/1510990.

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This study evaluated the relative effectiveness of three variations of a computer program designed to increase the sight-word reading vocabulary of young children. Subjects were 17 school-identified learning disabled children in grades 1, 2, and 3. A multi-element baseline design was used to expose all subjects to three different treatment conditions and a no-treatment control condition. In the treatment conditions, word sets consisting of 10 words each were practiced on versions of the computer program that employed either graphic representation of the words alone (visual-only), graphics plus synthetic speech (visual-auditory), or synthetic speech alone (auditory-only). All treatment conditions resulted in significant improvements in accuracy and speed of word identification, with no differences among treatments. The results are discussed in terms of implications for the design of reading software for young children.

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Greenberg, Berton. "The Ladell Diffractometer: Geometry and Applications." Advances in X-ray Analysis 36 (1992): 631–40. http://dx.doi.org/10.1154/s0376030800019285.

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AbstractThe Ladell x-ray diffractometer (LD) is designed to study “practical” polycrystalline materials. These are materials which exhibit some combination of texture, strain, and large grain size, or are inhomogeneous or anisotropic in other ways. LD features which make this possible are: the ability to study crystal planes inclined to the sample surface; a versatile reflection geometry; high 2θ resolution via a focusing geometry; a large irradiated sample area (up to 1.5 cm2) for improved intensity and sampling statistics; the ability to examine different sample areas to test for homogeneity; and the use of one sample with no instrument reconfiguration. Scans and/or applications are described that measure texture, strain, twinning, improve quantitative phase analysis, and eliminate substrate scattering.The LD makes use of five independent computer controlled motions. These enable one to study a large fraction of that part of reciprocal space which is accessible by reflection. Instrument geometry and scans are described in terms of α, θ and reciprocal space diagrams. The effect of specimen displacement on peak position is described as are the effects of a number of geometrical factors on integrated intensity.

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Stevens, J. R., and M. Tibayrenc. "Detection of linkage disequilibrium in Trypanosoma brucei isolated from tsetse flies and characterized by RAPD analysis and isoenzymes." Parasitology 110, no. 2 (February 1995): 181–86. http://dx.doi.org/10.1017/s0031182000063940.

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SUMMARYThis study analyses the different populations of Trypanosoma brucei spp. which may coexist within the midgut of wild tsetse flies (Stevens et al. 1994). Cloned trypanosome populations characterized by multilocus enzyme electrophoresis (MLEE) were further analysed by the random amplified polymorphic DNA (RAPD) technique, allowing detection of genetic variation at a finer level than that possible by MLEE. Genetic distance matrices derived from the results of each of the two biochemical methods were calculated and compared using a computer program based on the method of Mantel (1967). The observed correlation was used to investigate the degree of linkage disequilibrium (LD) in the data, association between unrelated polymorphic markers providing a measure of the departure from panmixia. The potential of each biochemical method to detect linkage was evaluated by an extended Mantel test. The MLEE/RAPD correlation test evidenced significant LD within the population, suggesting a predominantly clonal method of reproduction for these West African trypanosomes. Analysis of RAPD data by the extended Mantel test also showed significant LD, while the results with MLEE data were less conclusive, providing an indication of the relative potential of the two techniques to detect fine genetic variation.

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Franken, P., I. Tobler, and A. A. Borbely. "Varying photoperiod in the laboratory rat: profound effect on 24-h sleep pattern but no effect on sleep homeostasis." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 269, no. 3 (September 1, 1995): R691—R701. http://dx.doi.org/10.1152/ajpregu.1995.269.3.r691.

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To assess the influence of the photoperiod on sleep regulation, laboratory rats were adapted to a long photoperiod (LPP; 16:8-h light-dark cycle, LD 16:8) or a short photoperiod (SPP; LD 8:16). The electroencephalogram (EEG) and cortical temperature (TCRT) were continuously recorded for a baseline day, a 24-h sleep deprivation (SD) period, and a recovery day. Data obtained previously for LD 12:12 served for comparison. Whereas the photoperiod exerted a prominent effect on the 24-h sleep pattern, the 24-h baseline level of sleep and the response to SD were little affected. Recovery from SD was characterized by a marked rise in rapid eye movement sleep, a moderate rise in non-rapid eye movement sleep, and an initial enhancement of EEG slow-wave activity followed by a decrease below baseline. The amplitude and phase of the "unmasked" 24-h component of TCRT did not differ between LPP and SPP. Computer simulations demonstrated that the changes of TCRT and EEG slow-wave activity can be largely accounted for by the sequence of the vigilance states. We conclude that the photoperiod does not affect the basic processes underlying sleep regulation.

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Duan, Dongliang, Louis L. Scharf, and Liuqing Yang. "LD approach to asymptotically optimum sensor fusion." IET Communications 11, no. 5 (March 30, 2017): 680–86. http://dx.doi.org/10.1049/iet-com.2016.0588.

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Journal articles on the topic 'LD. Computers'

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