Investigating the academic achievement of adolescents with learning disabilities: A structural modeling approach.

Although academic performance is a primary component of the federal definition of learning disabilities (LD), there have been few investigations of factors that influence academic growth among adolescents with LD. The focus of the present study is parental attitudes, their effects on adolescents with and without LD and on the academic achievement of those students. The estimated model accounted for 72% and 74% of the variance in academic achievement for the groups of students with and without LD, respectively. The findings support the position that parental expectations and perceptions of parental expectations are instrumental in raising the academic expectations and the achievement of adolescents with and without LD. The comparison between the students with and without LD showed that the most important factors were the same for both groups, suggesting the model worked in the same way for the two populations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Computing the Map of Geometric Minimal Cuts

In this paper we consider the following problem of computing a map of geometric minimal cuts (called MGMC problem): Given a graph G=(V,E) and a planar rectilinear embedding of a subgraph H=(V _H ,E _H ) of G, compute the map of geometric minimal cuts induced by axis-aligned rectangles in the embedding plane. The MGMC problem is motivated by the critical area extraction problem in VLSI designs and finds applications in several other fields. In this paper, we propose a novel approach based on a mix of geometric and graph algorithm techniques for the MGMC problem. Our approach first shows that unlike the classic min-cut problem on graphs, the number of all rectilinear geometric minimal cuts is bounded by a low polynomial, O(n ³). Our algorithm for identifying geometric minimal cuts runs in O(n ³logn(loglogn)³) expected time which can be reduced to O(nlogn(loglogn)³) when the maximum size of the cut is bounded by a constant, where n=|V _H |. Once geometric minimal cuts are identified we show that the problem can be reduced to computing the L _∞ Hausdorff Voronoi diagram of axis aligned rectangles. We present the first output-sensitive algorithm to compute this diagram which runs in O((N+K)log² NloglogN) time and O(Nlog² N) space, where N is the number of rectangles and K is the complexity of the Hausdorff Voronoi diagram. Our approach settles several open problems regarding the MGMC problem.     

Hazard analysis and critical control point of frying – safety assurance of fried foods

Deep frying can pose hazards due to oil deterioration (oxidation, polymerization, hydrolysis) and harmful components formation such as trans fatty acids, highly oxidized or polymerized constituents of fatty acids and acrylamide. An analysis of safety hazards of the production of the potato chips and french fries, was carried out from potato harvesting until final products packaging according to hazard analysis and critical control point approach focusing mainly on the first three principles. Since frying is considered a critical control point, the critical limits for the frying temperature and for the potential hazards must be controlled in order to ensure fried products safety.     

Differentiation of lactococci from 2 Greek cheeses with protected designation of origin by phenotypic criteria and RAPD-PCR

Abstract: Seventy‐six lactococci isolates from 2 protected designation of origin (PDO) cheeses were studied for their acidification ability, proteolytic activity, and inhibitory activities as well as their intraspecies characterization by randomly amplified polymorphic DNA‐polymerase chain reaction (RAPD‐PCR). Fifty‐two of them were characterized as Lactococcus lactis subsp. lactis by the SDS‐PAGE of whole‐cell proteins. The test strains increased the amount of acid in milk from 6 to 24 h as well as the quantities of amino acids on incubation for 4 d. The majority of the isolates degraded preferentially α_s‐casein. The isolates from Feta differed from those of Graviera Kritis in respect of β‐casein degradation. This fragment was either not degraded or underwent a small degradation by lactococci from Feta. A stronger intensity of acidification for the isolates from Feta and a higher casein breakdown ability for those from Graviera Kritis were also recorded. Lactococci from Feta and Graviera Kritis inhibited, preferentially, the growth of Escherichia coli O157:H7, and Yersinia enterocolitica, respectively. A high heterogeneity among the isolates according to RAPD‐PCR was determined, as well as grouping of the isolates according to their source of isolation. Selected isolates from each cheese could be used as starters to make either Feta or Graviera Kritis.     

Assessment of tremor activity in the Parkinson's disease using a set of wearable sensors

Tremor is the most common motor disorder of Parkinson's disease (PD) and consequently its detection plays a crucial role in the management and treatment of PD patients. The current diagnosis procedure is based on subject-dependent clinical assessment, which has a difficulty in capturing subtle tremor features. In this paper, an automated method for both resting and action/postural tremor assessment is proposed using a set of accelerometers mounted on different patient's body segments. The estimation of tremor type (resting/action postural) and severity is based on features extracted from the acquired signals and hidden Markov models. The method is evaluated using data collected from 23 subjects (18 PD patients and 5 control subjects). The obtained results verified that the proposed method successfully: 1) quantifies tremor severity with 87 % accuracy, 2) discriminates resting from postural tremor, and 3) discriminates tremor from other Parkinsonian motor symptoms during daily activities.     

Evaluation of direct manipulation using finger tracking for complex tasks in an immersive cube

A solution for interaction using finger tracking in a cubic immersive virtual reality system (or immersive cube) is presented. Rather than using a traditional wand device, users can manipulate objects with fingers of both hands in a close-to-natural manner for moderately complex, general purpose tasks. Our solution couples finger tracking with a real-time physics engine, combined with a heuristic approach for hand manipulation, which is robust to tracker noise and simulation instabilities. A first study has been performed to evaluate our interface, with tasks involving complex manipulations, such as balancing objects while walking in the cube. The user’s finger-tracked manipulation was compared to manipulation with a 6 degree-of-freedom wand (or flystick), as well as with carrying out the same task in the real world. Users were also asked to perform a free task, allowing us to observe their perceived level of presence in the scene. Our results show that our approach provides a feasible interface for immersive cube environments and is perceived by users as being closer to the real experience compared to the wand. However, the wand outperforms direct manipulation in terms of speed and precision. We conclude with a discussion of the results and implications for further research.     

Home curation versus teenage photography: Photo displays in the family home

In this paper we report an empirical study of the photographic portrayal of family members at home. Adopting a social psychological approach and focusing on intergenerational power dynamics, our research explores the use of domestic photo displays in family representation. Parents and their teenagers from eight families in the south of England were interviewed at home about their interpretations of both stored and displayed photos within the home. Discussions centred on particular photographs found by the participants to portray self and family in different ways. The findings show that public displays of digital photos are still curated by mothers of the households, but with more difficulty and less control than with analogue photos. In addition, teenagers both contribute and comply with this curation within the home, whilst at the same time developing additional ways of presenting their families and themselves online that are ‘unsupervised’ by the curator. We highlight the conflict of interest that is at play within teen and parent practices and consider the challenges that this presents for supporting the representation of family through the design of photo display technology.     

Cross-linking of β-casein by Trichoderma reesei tyrosinase and Streptoverticillium mobaraense transglutaminase followed by SEC–MALLS

Enzymatic modification of proteins, in order to produce functional materials such as hydrogels, adhesives and films via cross-linked networks or scaffolds of proteins, is a constantly evolving technology to create tailored micro- and nanostructured materials for food, cosmetic, and medical applications. For the successful utilization of oxidoreductases or transferases such as tyrosinases and transglutaminases, respectively, it is crucial to understand the action of these enzymes on protein substrates. In this study, cross-linking of the milk protein β-casein by Trichoderma reesei tyrosinase (TrTyr) was studied using size-exclusion chromatography (SEC) equipped with multi-angle light scattering (MALLS) and ultraviolet/visible (UV/Vis) detectors in order to determine the molecular mass (MM), radius of gyration (R_G) and degree of polymerization (DP) of the reaction products. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) was used to detect early polymerization states. The widely used Streptoverticillium mobaraense transglutaminase (Tgase) was used for comparison to tyrosinase from T. reesei. The results showed that cross-linking of β-casein by these two different types of enzymes resulted in the formation of polymerized reaction products with MM ranging from 500 to 1700 kg mol⁻¹ depending on the enzyme dosage and incubation time. The DP varied from 21 to 71, respectively. In the case of TrTyr the polymerized reaction products were slightly colored, and formation of the covalent cross-linking of β-casein could be monitored by UV/Vis as a function of incubation time.     

Exergy analysis of the energy use in Greece

In this work, an analysis is being done on the concept of energy and exergy utilization and an application to the residential and industrial sector of Greece. The energy and exergy flows over the period from 1990 to 2004 were taken into consideration. This period was chosen based on the data reliability. The energy and exergy efficiencies are calculated for the residential and industrial sectors and compared to the findings of a previous study concerning the exergy efficiency of the Greek transport sector. The residential energy and exergy efficiencies for the year 2003 were 22.36% and 20.92%, respectively, whereas the industrial energy and exergy efficiencies for the same year were 53.72% and 51.34%, respectively. The analysis of energy and exergy utilization determines the efficiency of the economy as a whole. The results can play an important role in the establishment of efficiency standards of the energy use in various economy sectors. These standards could be utilized by energy policy makers.     

Automated diagnosis of diseases based on classification: dynamic determination of the number of trees in random forests algorithm

The accurate diagnosis of diseases with high prevalence rate, such as Alzheimer, Parkinson, diabetes, breast cancer, and heart diseases, is one of the most important biomedical problems whose administration is imperative. In this paper, we present a new method for the automated diagnosis of diseases based on the improvement of random forests classification algorithm. More specifically, the dynamic determination of the optimum number of base classifiers composing the random forests is addressed. The proposed method is different from most of the methods reported in the literature, which follow an overproduce-and-choose strategy, where the members of the ensemble are selected from a pool of classifiers, which is known a priori. In our case, the number of classifiers is determined during the growing procedure of the forest. Additionally, the proposed method produces an ensemble not only accurate, but also diverse, ensuring the two important properties that should characterize an ensemble classifier. The method is based on an online fitting procedure and it is evaluated using eight biomedical datasets and five versions of the random forests algorithm (40 cases). The method decided correctly the number of trees in 90% of the test cases.