Location Of Dots Research Articles

Prenatal Choline Supplementation Improves Child Color-location Memory Task Performance at 7 Y of Age (FS05-01-19)

ObjectivesTo assess the effect of 3rd trimester maternal choline supplementation on child memory at 7 y of age. Animal studies have provided strong evidence that maternal choline supplementation improves offspring cognition, including memory, but few experimental studies have evaluated this intervention in humans. MethodsPregnant women (n = 26) were randomized to consume 480 mg (approx. the Adequate Intake [AI]) or 930 mg choline/d from gestational wk 27 until delivery as part of a controlled-feeding study. All food (providing 380 mg choline/d), choline supplements (100 mg or 550 mg/d), and prenatal vitamins were provided by the study. An ancillary follow-up was conducted to assess offspring cognitive functioning, including memory, at age 7 y (n = 20). Children performed a computer-based color-location memory task in which the location of dots on a cartoon figure were recalled after a retention interval (RI) of 1 or 8 s. The task increased in difficulty level (number of dots to be recalled; 1 to 5 dots) every 4 trials. Data were analyzed using mixed models; pairwise comparisons were corrected for multiplicity. ResultsChildren in the 930 mg/d group passed more levels than those in the 480 mg/d group (P = .048; see Figure), indicative of superior memory span. While the choline group by RI interaction was non-significant (P = .31), contrasts revealed that the 930 (v. 480) mg/d group tended to pass more levels at the 1 s RI (P = .052), but not at the 8 s RI (P = .58). Similarly, the analysis of total dots correct revealed a choline group by RI interaction (P = .08) such that children in the 930 (v. 480) mg/d group recalled more dots correctly at the 1 s RI (P = .02), but not at the 8 s RI (P > .99). ConclusionsChildren whose mothers consumed 930 (v. 480) mg choline/d performed significantly better on a task of color-location memory at age 7 y, suggesting a long-term beneficial effect of prenatal choline supplementation on offspring cognition in humans. These findings indicate that the choline AI for pregnant women may not be sufficient for optimal offspring cognitive functioning and raise concerns about choline intake during pregnancy in North America, which on average is only approx. 70% of the AI. Funding SourcesFunded by NIFA/USDA and the Balchem Corp. JEHN and CLB were supported by NIH Traineeships. CLB was supported by an Egg Nutrition Center Young Investigator Research Award for Early Exploration. Supporting Tables, Images and/or Graphs▪

Prenatal Choline Supplementation Improves Child Color-location Memory Task Performance at 7 Y of Age (FS05-01-19)

Abstract Objectives To assess the effect of 3rd trimester maternal choline supplementation on child memory at 7 y of age. Animal studies have provided strong evidence that maternal choline supplementation improves offspring cognition, including memory, but few experimental studies have evaluated this intervention in humans. Methods Pregnant women (n = 26) were randomized to consume 480 mg (approx. the Adequate Intake [AI]) or 930 mg choline/d from gestational wk 27 until delivery as part of a controlled-feeding study. All food (providing 380 mg choline/d), choline supplements (100 mg or 550 mg/d), and prenatal vitamins were provided by the study. An ancillary follow-up was conducted to assess offspring cognitive functioning, including memory, at age 7 y (n = 20). Children performed a computer-based color-location memory task in which the location of dots on a cartoon figure were recalled after a retention interval (RI) of 1 or 8 s. The task increased in difficulty level (number of dots to be recalled; 1 to 5 dots) every 4 trials. Data were analyzed using mixed models; pairwise comparisons were corrected for multiplicity. Results Children in the 930 mg/d group passed more levels than those in the 480 mg/d group (P = .048; see Figure), indicative of superior memory span. While the choline group by RI interaction was non-significant (P = .31), contrasts revealed that the 930 (v. 480) mg/d group tended to pass more levels at the 1 s RI (P = .052), but not at the 8 s RI (P = .58). Similarly, the analysis of total dots correct revealed a choline group by RI interaction (P = .08) such that children in the 930 (v. 480) mg/d group recalled more dots correctly at the 1 s RI (P = .02), but not at the 8 s RI (P > .99). Conclusions Children whose mothers consumed 930 (v. 480) mg choline/d performed significantly better on a task of color-location memory at age 7 y, suggesting a long-term beneficial effect of prenatal choline supplementation on offspring cognition in humans. These findings indicate that the choline AI for pregnant women may not be sufficient for optimal offspring cognitive functioning and raise concerns about choline intake during pregnancy in North America, which on average is only approx. 70% of the AI. Funding Sources Funded by NIFA/USDA and the Balchem Corp. JEHN and CLB were supported by NIH Traineeships. CLB was supported by an Egg Nutrition Center Young Investigator Research Award for Early Exploration. Supporting Tables, Images and/or Graphs

Visuospatial learning and memory in children pre- and posttemporal lobe resection: Patterns of localization and lateralization

In children with epilepsy, the impact of surgery including or sparing the mesial temporal lobes (TLs) on visuospatial memory has not been thoroughly investigated, and a clear pattern of hemispheric lateralization has not been observed. The primary aim of this study was to examine visuospatial learning and memory outcomes in children with epilepsy prior to and one year after surgical excision, to determine whether outcomes differed as a function of the localization and lateralization of surgical excisions. Forty-six children who underwent unilateral TL surgery with sparing of the mesial structures (TL group, N = 21, 16 left) or including mesial structures (TL + M group, N = 25 children, 12 left) were retrospectively recruited. Outcomes on the Children's Memory Scale (CMS) Dot Locations subtest (learning, immediate, and delayed recall scores) were examined prior to and following epilepsy surgery. Results revealed significantly reduced visuospatial memory (delayed recall) in the TL + M compared with the TL group after surgery. Despite this significant postoperative difference, there was no significant change in learning, immediate, or delayed recall scores in either group. However, inspection of individual change scores showed that fewer children in the TL + M group improved in delayed recall after surgery (7.2%) compared with children in the TL group (30%) whereas a similar proportion of children in the TL + M (30.4%) and TL (23.3%) groups showed a decline. There were no significant differences in learning or memory scores as a function of seizure laterality before or after surgery and no differences in change over time. Seizure outcome, age at surgery, age at seizure onset, and percentage life with epilepsy were not related to visuospatial learning or memory outcomes; however, greater number of antiepileptic drugs (AEDs) following surgery was related to poorer visuospatial memory (delayed recall) in the TL + M group. In summary, the results show that visuospatial learning and memory performance do not seem to show a significant decline following TL resections in childhood, regardless of whether or not surgery includes the mesial TL and involves the left or right hemisphere. However, although mesial TL excisions might not result in a deficit in visuospatial memory, they may hinder progressions made after surgery. Further research is needed to examine how resection of the mesial TL (alone or in combination with lateral TL structures) affects visuospatial memory outcomes in children, as well as to investigate the degree to which other treatment factors, such as medication, may affect visual memory outcomes.

The effects of Hebb repetition learning and temporal grouping in immediate serial recall of spatial location.

The Hebb repetition effect is a phenomenon in which a repeated presentation of the same list increases the performance in immediate serial recall. This provided the theoretical basis for a core assumption of the Atkinson and Shiffrin model regarding information transfer from short-term memory to long-term memory. The Hebb repetition effect was originally reported for the verbal domain, but subsequent studies found similar phenomena using visuospatial paradigms, for example, in serial-order memory for dot locations. The present study examined in two experiments the effects of presentation timing of nine spatial locations on Hebb repetition learning. In Experiment 1, the Hebb repetition effects were observed for spatial locations with constant timing presentation as well as temporal grouping presentation. In the latter condition, all lists were presented with the same temporal structure, that is, temporal pauses were inserted after the third and sixth serial positions. This manipulation led to a better recall performance in comparison with the constant presentation, but did not interact with the repetition. In Experiment 2, the Hebb list was presented with a different temporal structure in every repetition in the random-grouping condition. Although this manipulation is known to eliminate or weaken the Hebb effect in the verbal domain, we observed stable repetition effects in this experiment. This suggests that there might be some domain-specific mechanisms in Hebb repetition learning. These results may facilitate the development of theories of the relationship between short-term and long-term memory.

Examining the Role of Spatial Changes in Bimodal and Uni-Modal To-Be-Ignored Stimuli and How They Affect Short-Term Memory Processes.

This study examines the potential vulnerability of short-term memory processes to distraction by spatial changes within to-be-ignored bimodal, vibratory, and auditory stimuli. Participants were asked to recall sequences of serially presented digits or locations of dots while being exposed to to-be-ignored stimuli. On unexpected occasions, the bimodal to-be-ignored sequence, vibratory to-be-ignored sequence, or auditory to-be-ignored sequence changed their spatial origin from one side of the body (e.g., ear and arm, arm only, ear only) to the other. It was expected that the bimodal stimuli would make the spatial change more salient compared to that of the uni-modal stimuli and that this, in turn, would yield an increase in distraction of serial short-term memory in both the verbal and spatial domains. Our results support this assumption as a disruptive effect of the spatial deviant was only observed when presented within the bimodal to-be-ignored sequence: uni-modal to-be-ignored sequences, whether vibratory: or auditory, had no impact on either verbal or spatial short-term memory. Implications for models of attention capture and the potential special attention capturing role of bimodal stimuli are discussed.

AC Electrokinetics of Polarizable Tri-Axial Ellipsoidal Nano-Antennas and Quantum Dot Manipulation.

By realizing the advantages of using a tri-axial ellipsoidal nano-antenna (NA) surrounded by a solute for enhancing light emission of near-by dye molecules, we analyze the possibility of controlling and manipulating the location of quantum dots (similar to optical tweezers) placed near NA stagnation points, by means of prevalent AC electric forcing techniques. First, we consider the nonlinear electrokinetic problem of a freely suspended, uncharged, polarized ellipsoidal nanoparticle immersed in a symmetric unbounded electrolyte which is subjected to a uniform AC ambient electric field. Under the assumption of small Peclet and Reynolds numbers, thin Debye layer and ‘weak-field’, we solve the corresponding electrostatic and hydrodynamic problems. Explicit expressions for the induced velocity, pressure, and vorticity fields in the solute are then found in terms of the Lamé functions by solving the non-homogeneous Stokes equation forced by the Coulombic density term. The particular axisymmetric quadrupole-type flow for a conducting sphere is also found as a limiting case. It is finally demonstrated that stable or equilibrium (saddle-like) positions of a single molecule can indeed be achieved near stagnation points, depending on the directions of the electric forcing and the induced hydrodynamic (electroosmotic) and dielectrophoretic dynamical effects. The precise position of a fluorophore next to an ellipsoidal NA, can thus be simply controlled by adjusting the frequency of the ambient AC electric field.

Impact of Early Diabetic Ketoacidosis on the Developing Brain.

OBJECTIVEThis study examined whether a history of diabetic ketoacidosis (DKA) is associated with changes in longitudinal cognitive and brain development in young children with type 1 diabetes.RESEARCH DESIGN AND METHODSCognitive and brain imaging data were analyzed from 144 children with type 1 diabetes, ages 4 to <10 years, who participated in an observational study of the Diabetes Research in Children Network (DirecNet). Participants were grouped according to history of DKA severity (none/mild or moderate/severe). Each participant had unsedated MRI scans and cognitive testing at baseline and 18 months.RESULTSIn 48 of 51 subjects, the DKA event occurred at the time of onset, at an average of 2.9 years before study entry. The moderate/severe DKA group gained more total and regional white and gray matter volume over the observed 18 months compared with the none/mild group. When matched by age at time of enrollment and average HbA1c during the 18-month interval, participants who had a history of moderate/severe DKA compared with none/mild DKA were observed to have significantly lower Full Scale Intelligence Quotient scores and cognitive performance on the Detectability and Commission subtests of the Conners’ Continuous Performance Test II and the Dot Locations subtest of the Children’s Memory Scale.CONCLUSIONSA single episode of moderate/severe DKA in young children at diagnosis is associated with lower cognitive scores and altered brain growth. Further studies are needed to assess whether earlier diagnosis of type 1 diabetes and prevention of DKA may reduce the long-term effect of ketoacidosis on the developing brain.

Joint attention is intact even when visuospatial working memory is occupied

The gaze of another modulates and shifts an observer’s spatial attention toward this gaze direction. This phenomenon is termed joint attention. Although previous studies found joint attention was induced during a spatial working memory task, it remains an open question whether spatial working memory interferes with joint attention. To address this question, we conducted a dual task paradigm consisting of gaze cuing and spatial working memory tasks. The gaze cuing task requires that participants respond to the location of an abrupt onset of a target while ignoring the gaze of a facial image located at the center of the display. In the spatial working memory task, participants memorized two or three locations of small dots and judged whether these locations changed in the probe screen. In the dual task condition, while participants were maintaining spatial information of the spatial working memory task, they performed the gaze cuing task. In Experiment 1, maintaining spatial information did not impair the magnitude of joint attention. In Experiment 2, we increased load of spatial working memory task, and still observed results similar to Experiment 1. In Experiment 3, we replicated the findings in Experiment 1 when an identification task was conducted. In addition, we measured electrooculographic signals to investigate eye movements of participants during the task. The study provides that joint attention is intact even if spatial working memory is occupied.

Abstract shape representation in human visual perception.

The ability to form shape representations from visual input is crucial to perception, thought, and action. Perceived shape is abstract, as evidenced when we can see a contour specified only by discrete dots, when a cloud appears to resemble a fish, or when we match shapes across transformations of scale and orientation. Surprisingly little is known about the formation of abstract shape representations in biological vision. We report experiments that demonstrate the existence of abstract shape representations in visual perception and identify the time course of their formation. In Experiment 1, we varied stimulus exposure time in a task that required abstract shape and found that it emerges about 100 ms after stimulus onset. The results also showed that abstract shape representations are invariant across certain transformations and that they can be recovered from spatially separated dots. Experiment 2 found that encoding of basic visual features, such as dot locations, occurs during the first 30 ms after stimulus onset, indicating that shape representations require processing time beyond that needed to extract spatial features. Experiment 3 used a convergent method to confirm the timing and importance of abstract shape representations. Given sufficient time, shape representations form automatically and obligatorily, affecting performance even in a task in which neither instructions nor accurate responding involved shape. These results provide evidence for the existence, emergence, and functional importance of abstract shape representations in visual perception. We contrast these results with "deep learning" systems and with proposals that deny the importance of abstract representations in human perception and cognition. (PsycINFO Database Record

Directed Self-Assembly of Ge Quantum Dots Using Focused Si2+ Ion Beam Patterning

We show that templating a Si surface with a focused beam of Si2+ or Si+ ions can create suitable nucleation sites for the subsequent growth of self-assembled Ge quantum dots by chemical vapor deposition. To determine the mechanism of patterning we use atomic force microscopy to show that, similar to Ga+ patterning, the formation of a surface pit is required to enable control over Ge quantum dot locations. We find that relatively high implantation doses are required to achieve patterning, and these doses lead to amorphization of the substrate. We assess the degree to which the substrate crystallinity can be recovered by subsequent processing. Using in situ transmission electron microscopy heating experiments we find that recrystallization is possible at the growth temperature of the Ge quantum dots, but defects remain that follow the pattern of the initial implantation. We discuss the formation mechanism of the defects and the benefits of using Si ions for patterning both defects and quantum dots on Si substrates.

The contribution of perceptual factors and training on varying audiovisual integration capacity.

The suggestion that the capacity of audiovisual integration has an upper limit of 1 was challenged in 4 experiments using perceptual factors and training to enhance the binding of auditory and visual information. Participants were required to note a number of specific visual dot locations that changed in polarity when a critical auditory stimulus was presented, under relatively fast (200-ms stimulus onset asynchrony [SOA]) and slow (700-ms SOA) rates of presentation. In Experiment 1, transient cross-modal congruency between the brightness of polarity change and pitch of the auditory tone was manipulated. In Experiment 2, sustained chunking was enabled on certain trials by connecting varying dot locations with vertices. In Experiment 3, training was employed to determine if capacity would increase through repeated experience with an intermediate presentation rate (450 ms). Estimates of audiovisual integration capacity (K) were larger than 1 during cross-modal congruency at slow presentation rates (Experiment 1), during perceptual chunking at slow and fast presentation rates (Experiment 2), and, during an intermediate presentation rate posttraining (Experiment 3). Finally, Experiment 4 showed a linear increase in K using SOAs ranging from 100 to 600 ms, suggestive of quantitative rather than qualitative changes in the mechanisms in audiovisual integration as a function of presentation rate. The data compromise the suggestion that the capacity of audiovisual integration is limited to 1 and suggest that the ability to bind sounds to sights is contingent on individual and environmental factors. (PsycINFO Database Record

Near-independent capacities and highly constrained output orders in the simultaneous free recall of auditory-verbal and visuo-spatial stimuli.

Three experiments examined the immediate free recall (IFR) of auditory-verbal and visuospatial materials from single-modality and dual-modality lists. In Experiment 1, we presented participants with between 1 and 16 spoken words, with between 1 and 16 visuospatial dot locations, or with between 1 and 16 words and dots with synchronized onsets. We found that for dual-modality lists (a) overall performance, initial recalls, and serial position curves were largely determined by the within-modality list lengths, (b) there was only a small degree of dual-task trade-off (that was limited to the visuospatial items), and (c) there were strongly constrained output orders: participants tended to alternate between words and dots from equivalent or neighboring serial positions. In Experiments 2 and 3, we compared lists of 6 single-modality items with dual-modality lists of 6 words and 6 dots with synchronous or alternating onsets (Experiment 2), or random but asynchronous onsets (Experiment 3). In all 3 dual-modality conditions, we again found only a small trade-off in visuospatial (but not verbal) IFR performance. There were similarly highly constrained output orders with the synchronous and alternating onsets, and these patterns were present but attenuated with the randomized onsets. We propose that both auditory-verbal and visuospatial list items are associated with a common temporal episodic context that is used to guide cross-modal retrieval, and we speculate that the limited, asymmetric interference could arise because the less variable representations of the dots share only a relatively small subset of features with the more variable representations of the words. (PsycINFO Database Record

Categorization difficulty modulates the mediated route for response selection in task switching.

Conflict during response selection in task switching is indicated by the response congruency effect: worse performance for incongruent targets (requiring different responses across tasks) than for congruent targets (requiring the same response). The effect can be explained by dual-task processing in a mediated route for response selection, whereby targets are categorized with respect to both tasks. In the present study, the author tested predictions for the modulation of response congruency effects by categorization difficulty derived from a relative-speed-of-processing hypothesis. Categorization difficulty was manipulated for the relevant and irrelevant task dimensions in a novel spatial task-switching paradigm that involved judging the locations of target dots in a grid, without repetition of dot configurations. Response congruency effects were observed and they varied systematically with categorization difficulty (e.g., being larger when irrelevant categorization was easy than when it was hard). These results are consistent with the relative-speed-of-processing hypothesis and suggest that task-switching models that implement variations of the mediated route for response selection need to address the time course of categorization.

Exploring the Influence of Variability on Single-Electron Transistors Into SET-Based Circuits

We analyze the performance of hybrid single-electron transistor (SET)–FET circuits when different variability sources are considered, e.g., SET’s quantum dot location and FET device dimension variations. For the FET device, FinFET and vertical nanowire configurations have been studied. The hybrid SET–FET circuits with both SET and FET in vertical topology depict the best circuit performance and the highest integration level. The variability impact on different SET-based circuits has been analyzed, including negative differential resistance and logic inverters.

Simulation of the effect of quantum dot location on a quantum dot p-i-n junction solar cell

The investigation of the new generation of a photovoltaic cell for the optimized parameters is mainly carried out using modeling and simulation, because the fabrication of quantum structures is still a challenge. Hence, new models to simulate realistic devices are developed. In the past, the Drift Diffusion equation has been exploited to simulate quantum well solar cells by introducing various assumptions and new parameters. Non Equilibrium Green Function’s Formalism has been widely used to study the transport in the nanostructures of the photovoltaic devices. We have developed a model of simulating quantum dot (QD) [Formula: see text]-[Formula: see text]-[Formula: see text] junction solar cell by hybridizing the Drift Diffusion Equation and the Transfer Hamiltonian Approach. The developed model is applied to a QD [Formula: see text]-[Formula: see text]-[Formula: see text] junction solar cell to determine the optimized position of the QD within the intrinsic region. Our results show that when the QD is placed closer to the edges of the [Formula: see text]-region, the highest possible efficiency is observed.

Learning and Memory in Adolescents With Critical Biventricular Congenital Heart Disease.

Although evidence exists of broadly defined memory impairment among adolescents with critical congenital heart disease (CHD), nuanced investigations of declarative memory in this at-risk population have not been conducted. This study had two primary aims: (1) to conduct a fine-grained analysis of a range of relevant learning and memory processes in adolescents with critical biventricular CHD, and (2) to identify risk, odds, and predictors of memory impairment. Data were combined from two single-center studies of neurodevelopmental outcomes in critical CHD. Two-hundred seven adolescents (M age =15.61±1.0 years) with critical CHD (139 with dextro-transposition of the great arteries and 68 with tetralogy of Fallot without an identified genetic condition), as well as 61 healthy referents (M age =15.27±1.1 years) completed a neuropsychological evaluation which included the Children's Memory Scale. Whereas visual-spatial memory deficits were found in both CHD subgroups, verbal memory abilities were relatively preserved. Adolescents with CHD demonstrated stronger memory for Stories than Word Pairs, t (203)=2.63, p=.009, and for Dot Locations than Faces, t(204)=-2.57, p=.01. CHD subgroup, socioeconomic status, sex, and seizure history were among the most frequent significant predictors of memory impairment. Seizure history, in particular, was associated with a 2 to 3 times greater odds of impaired performance on learning and memory tasks. Adolescents with critical biventricular CHD are at risk for deficits in aspects of declarative memory. Independent risk factors for worse outcome include history of seizures. (JINS, 2017, 23, 627-639).

Taking a(c)count of eye movements: Multiple mechanisms underlie fixations during enumeration.

We habitually move our eyes when we enumerate sets of objects. It remains unclear whether saccades are directed for numerosity processing as distinct from object-oriented visual processing (e.g., object saliency, scanning heuristics). Here we investigated the extent to which enumeration eye movements are contingent upon the location of objects in an array, and whether fixation patterns vary with enumeration demands. Twenty adults enumerated random dot arrays twice: first to report the set cardinality and second to judge the perceived number of subsets. We manipulated the spatial location of dots by presenting arrays at 0°, 90°, 180°, and 270° orientations. Participants required a similar time to enumerate the set or the perceived number of subsets in the same array. Fixation patterns were systematically shifted in the direction of array rotation, and distributed across similar locations when the same array was shown on multiple occasions. We modeled fixation patterns and dot saliency using a simple filtering model and show participants judged groups of dots in close proximity (2°-2.5° visual angle) as distinct subsets. Modeling results are consistent with the suggestion that enumeration involves visual grouping mechanisms based on object saliency, and specific enumeration demands affect spatial distribution of fixations. Our findings highlight the importance of set computation, rather than object processing per se, for models of numerosity processing.

The role of executive functioning in memory performance in pediatric focal epilepsy.

Learning and memory are essential for academic success and everyday functioning, but the pattern of memory skills and its relationship to executive functioning in children with focal epilepsy is not fully delineated. We address a gap in the literature by examining the relationship between memory and executive functioning in a pediatric focal epilepsy population. Seventy children with focal epilepsy and 70 typically developing children matched on age, intellectual functioning, and gender underwent neuropsychological assessment, including measures of intelligence (Wechsler Abbreviated Scale of Intelligence [WASI]/Differential Ability Scales [DAS]), as well as visual Children's Memory Scale (CMS Dot Locations) and verbal episodic memory (Wide Range Assessment of Memory and Learning [WRAML] Story Memory and California Verbal Learning Test for Children [CVLT-C]). Executive functioning was measured directly (WISC-IV Digit Span Backward; Clinical Evaluation of Language Fundamentals, Fourth Edition (CELF-IV) Recalling Sentences) and by parent report (Behavior Rating Inventory of Executive Function [BRIEF]). Children with focal epilepsy had lower delayed free-recall scores than controls across visual and verbal memory tasks (p = 0.02; partial η2 = 0.12). In contrast, recognition memory performance was similar for patients and controls (p = 0.36; partial η2 = 0.03). Children with focal epilepsy demonstrated difficulties in working memory (p = 0.02; partial η2 = 0.08) and planning/organization (p = 0.02) compared to controls. Working memory predicted 9-19% of the variance in delayed free recall for verbal and visual memory; organization predicted 9-10% of the variance in verbal memory. Patients with both left and right focal epilepsy demonstrated more difficulty on verbal versus visual tasks (p = 0.002). Memory performance did not differ by location of seizure foci (temporal vs. extratemporal, frontal vs. extrafrontal). Children with focal epilepsy demonstrated memory ability within age-level expectations, but delayed free recall was inefficient compared to typically developing controls. Memory difficulties were not related to general cognitive impairment or seizure localization. Executive functioning accounted for significant variance in memory performance, suggesting that poor executive control negatively influences memory retrieval.

Risk Management in Implementing Wind Energy Project

Analysis of possible risks in the process of implementing a specific project has been carried out, measures to reduce their negative impact on the project have been developed and proposed. The object of study is a wind energy project, namely a wind farm working as part of the national energy system. The implementation of the project is related to both external and internal risk factors that are characteristic to such projects in the real economy sector under the current conditions. Such risks have been classified and the fractional structure of risk adjustment has been analysed taking into account the properties of the particular wind energy project, which consists of three main components. A description has been given of the innovative technology selected for project implementation, power generation using wind, which is used to limit the negative influence of the above-mentioned risks. The current strategic management tools, such as SWOT analysis and McKinsey matrix, which are useful for the identification of project risks, have been examined. For the wind energy project that is being implemented, the project dot location coordinates were determined in the McKinsey matrix on axes: Advantages against competitors and Market attractiveness. Also, a sector characterising the project development prospects was established to be subsequently used as a tool for risk identification. Following the identification of risks, specific measures of state support and special project management measures were developed and proposed to be implemented with the aim of limiting the negative influence of the possible project risks.

A Trainless Recognition of Handwritten Persian/Arabic Letters using Primitive Elements

his paper aim at applying primitive elements composing Persian/Arabic to recognize offline handwritten letters. To do so, eight primitive elements are used that with them all Persian/Arabic are shaped. Having undergone these modifications, the get thinned, and then enter the primitive extraction phase. At this stage through using strokes, the letters primitive elements would be extracted and by making Stroke Identification Vector (SIV) and then comparing with Character Identification Vectors (CIV) the recognition is gained. Then the number and location of dots on the and also the location of the towards the baseline was extracted. According to this method, unlike common recognition methods of handwritten methods, no training is required and two processes of separation and recognition are accomplished simultaneously. This algorithm is rule base and according several rule recognition is done. The accuracy of this algorithm in digit recognition is 98.8%. Also recognition on isolated Persian/Arabic words that approximately constitute 50% of the sub words in Persian/Arabic texts is 88.7%, for two sub word that make up about 32% of text is 81.4%, for three sub word that approximately constitute 12% of the texts is 73.6% and four that make up 5% of text the accuracy is 69.7%.