Search

We compute the absorbing number of the edge ideals of special graphs such as complete graphs, path graphs, and cycle graphs. We also compute the absorbing number for other monomial ideals. In special cases, we show that the length of a prime filtration of a monomial ideal I is an upper bound for its absorbing number. [ABSTRACT FROM AUTHOR]

The terms “hotspots,” “blackspot,” or “high‐risk” are normally used for an area on a road where the number of car accidents are far beyond the normal level and, more importantly, the causes of the incident always link to one or many specific reasons. Identifying these spots is helpful and may assist people in authority to implement corrective actions. To do the aforementioned, some decision‐support tools could be useful since they enable us to monitor the indicators that may lead to a car accident, same as the procedure engineers use to control production lines in factories. In this regard, control charts are utilized to identify blackspots. Although the method is low cost, and provides quick detection and statistical reliability level and, more importantly, uses online applications; however, it advised that the rate quality control method could be used on roads with the same geometry and traffic conditions. This research develops a hybrid method, based on accident type, for improving rate quality control method to overcome the shortcomings. Furthermore, the suggested framework considers crash severity and traffic volume that have not been taken into account in the rate quality control method yet. The case study evaluates how this framework is successful to identify blackspots, and based on the result in the real environment, it reveals that the proposed method could detect and identify the hotspots. [ABSTRACT FROM AUTHOR]

Vehicles experience off-axial loads as well as axial loads during collisions. Hence, it is essential to have oblique loads be involved in investigating thin-walled tubes in vehicles as energy absorbers. In this paper, to find the optimum design of a segmented tube in terms of various collision scenarios, the RSM D-Optimal Design is used along with MULTIMOORA as a multiple-attribute decision-making (MADM) method. The tube consists of three parts having different thicknesses and lengths. Energy absorption, initial peak load, and maximum load in three angles of loads (0∘, 15∘, and 30∘), and masses of the tube were defined as independent objectives. Design points were constructed to obtain all responses through finite elements method (FEM). It was found that the obtained models of responses predict the crashworthiness with acceptable accuracy. Then the optimization provides fifteen Pareto front designs of tubes through fifteen different scenarios. Finally, the integration of MULTIMOORA within a combinative weighting method selected the best tube from the optimums. The contrast between the optimum basic tube and the selected segmented tube demonstrated that the latter was capable of increasing the energy absorption by 24–41%, and reducing the initial peak load by 50–60% for the three applied loads. [ABSTRACT FROM AUTHOR]

Let I ⊂ K [ x 1 , ... , x n ] be a squarefree monomial ideal generated in one degree. Let G I be the graph whose nodes are the generators of I, and two vertices u i and u j are adjacent if there exist variables x, y such that x u i = y u j . We show that if I is generated in degree n - 2 , then the following are equivalent: G I is a connected graph; I has a (n - 2) -linear resolution; I has linear quotients; I is a variable-decomposable ideal. We also prove that if I has linear relations and G I ¯ is chordal, then I has linear quotients. [ABSTRACT FROM AUTHOR]

Introduction: Transcranial near-infrared photobiomodulation (NIR-PBM) is a new noninvasive procedure which transcranially applies a near-infrared wavelength to the scalp with a laser or a light-emitting diode (LED) source. Improvement in the neurological or psychological symptoms has been reported following light irradiation. However, to our knowledge, there is no study to investigate the effects of transcranial NIR-PBM on motor performance directly. Therefore, the objective of this study was to investigate the short-term effects of transcranial NIR-PBM on motor performance in healthy human subjects. Methods: In this experimental single-blind randomized clinical trial study, 56 right-handed healthy participants, whose ages ranged from 18 to 30, were randomly assigned to (1) Real transcranial NIR-PBMC3 group (n=14), (2) Sham transcranial NIR-PBMC3 group (n=14), (3) Real transcranial NIR-PBMC4 group (n=14), and (4) Sham transcranial NIR-PBMC4 group (n=14). We applied the 808 nm laser with irradiation energy density of 60 J/cm2 and power density of 200 mw/cm2 to the C3 or C4 points of the scalp. The number of finger taps as an indicator of motor performance was assessed by the finger-tapping test (FTT) before and after irradiation of transcranial NIR-PBM on the corresponding points of the scalp for 5 minutes. Results: The results showed that the number of finger taps in both right and left hands following the use of transcranial NIR-PBM in the real transcranial NIR-PBMC3 group significantly increased (P < 0.05). Conclusion: We concluded that using transcranial NIR-PBM with a laser source on C3 point of the motor cortex in right-handed healthy people can increase the number of finger taps in both hands as an indicator of motor performance improvement. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the electrophysiological effects of the photobiomodulation (PBM) by the quantitative electroencephalography (qEEG) as a diagnostic method. The neurotherapeutic potential of transcranial PBM has been recently investigated in preclinical and clinical studies. According to the PBM mechanisms of action on increasing the cerebral blood flow and the neuronal firing, a change may occur in cortical electrical activity after transcranial PBM that could be revealed in qEEG. A total of 30 participants (15 males and 15 females) were included in this experimental study in a convenience sampling method. A 19-channel EEG was obtained from subjects, before and after receiving sham or real 850-nm PBM by light emitting diode (LED) array on the right prefrontal cortex (PFC). An attentional task also was completed by the participant before and after the irradiation. Results presented that the effect of PBM on the reaction time was significant (p = 0.001) in favor of the real-treatment group (p < 0.05). For the absolute power, repeated-measures ANOVA showed a significant interaction of group × time × frequency (p = 0.04). In the real-treatment group, absolute power of delta band was significantly reduced in all electrodes (p < 0.05). Also, a similar significant interaction of group × time × frequency was seen for relative power (p = 0.04). Post-hoc analysis showed a significant decrease in delta band after PBM in the real treatment group (p < 0.05). The study presented that light irradiation with 850-nm LED source on right PFC could change brain electrical activity and has beneficial effects on attentional performance. [ABSTRACT FROM AUTHOR]

A majority of decision-making problems are accompanied by some kinds of predictions and uncertainties. Therefore, interval data are widely used instead of exact data. The elimination and choice expressing reality methods, referred to as ELECTRE, belong to the outranking methods. Despite their relative complexity, avoiding compensation between criteria is one of the main advantages of the ELECTRE methods. However, no version of ELECTRE methods has the capability to deal with both interval data and target-based criteria. Target-based criteria are applicable in many areas ranging from material selection to medical decision-making problems. Efficiency of the modified ELECTRE method (ELECTRE-IDAT) was examined through two challenging examples. Also, a sensitivity analysis was performed to show advantages of the ELECTRE-IDAT approach. Additionally, the concept of bounded criteria was explained and applicability of interval data as well as benefit, cost, and target criteria were described with a biomaterial selection problem. [ABSTRACT FROM AUTHOR]

Recently, considerable attention has been devoted to application of multi-attribute decision- making (MADM) method in materials selection. Normalization can be considered as a foundation for rational MADM methods, which should deal with target-based criteria in addition to cost and benefit criteria. Although a good number of applications have been reported for point target criteria in MADM problems, in selection problems related to engineering design, it might be better to let the material and design criteria vary over a range in order to increase flexibility in subsequent design stages. The mentioned point supports a readily adaptable design in changing the customer requirements, which is also significant in offering a robust design. In this research, performance of three promising target-based normalization methods was investigated using simulation experiments to examine the effect of simulation parameters. The effect of parameters and normalization methods was examined using analysis of variance (ANOVA). Moreover, the best structure formula was identified to propose an inclusive range target-based normalization method. The suggested normalization method was used to enhance the capability of Weighted Aggregated Sum Product Assessment (WASPAS) method and applied to a real-word problem dealing with benefit-, cost-, and point target-based criteria as well as the range criterion. [ABSTRACT FROM AUTHOR]

Background: As there is no standard aphasia screening tool for Azeri language yet, the aim of this study was to develop an aphasia screening test with acceptable validity and reliability. Methods: The present study was conducted in two phases. In the first phase, by literature search, the screening test was designed and to obtain validity it was peer reviewed by expert panel. After collecting experts' ratings and comments, appropriate modifications were applied. For test-retest reliability in the second phase, edited test was administered in 32 patients with brain injuries, then the retest was performed two weeks later. Results: The developed test had eight subscales including: A) picture description, B) syntax, C) linguistic reasoning, D) descriptive naming, E) perception of minimal pairs, F) comprehensive vocabulary, G) expressive vocabulary, H) verbal fluency. Each section had five questions except verbal fluency which had 3 items. Content validity ratio (CVR) according to Lawshe’s approach, was 82% for the whole test. Intraclass correlation for all subscales were more than 0.8. Cronbach's alpha coefficient for internal reliability was 0.901. Conclusion: This aphasia screening test seems to have acceptable psychometric properties. This test can probably be used in clinical setting by specialists. [ABSTRACT FROM AUTHOR]

In this paper we study the Castelnuovo{Mumford regularity of an edge ideal associated with a graph in a special class of well-covered graphs. We show that if G belongs to the class SQ, then the Castelnuovo{Mumford regularity of R/I(G) will be equal to induced matching number of G. For this class of graphs we also compute the projective dimension of the ring R/I(G) . As a corollary we describe these invariants in well-covered forests, well-covered chordal graphs, Cohen{Macaulay Cameron-Walker graphs, and simplicial graphs. [ABSTRACT FROM AUTHOR]

Let $$\Delta $$ be a simplicial complex on vertex set $$[n]$$ . It is shown that if $$\Delta $$ is complete intersection, Cohen-Macaulay of codimension 2, Gorenstein of codimension 3, or 2-Cohen-Macaulay of codimension 3, then $$\Delta $$ is vertex decomposable. As a consequence, we show that if $$\Delta $$ is a simplicial complex such that $$I_\Delta = I_t(C_n)$$ , where $$I_t(C_n)$$ is the path ideal of length $$t$$ of $$C_n$$ , then $$\Delta $$ is vertex decomposable if and only if $$t=n, t=n-1$$ , or $$n$$ is odd and $$t=(n-1)/2$$ . [ABSTRACT FROM AUTHOR]

Two major requirements for crush analysis of thin-walled cylindrical tubes are being lightweight and having good crashworthiness. Thin-walled cylindrical tubes, which are either empty or foam filled, can potentially be used in all vehicles and moving parts such as road vehicles, train, aircrafts, ships, lifts and machinery to protect passengers and the structure itself during impact. This paper discusses an idea of utilizing the initiator on the foam-filled thin-walled circular tubes with stiffened annular rings to increase the specific energy absorption (SEA) and prevent the sudden force applied to the main part of the automotive and its occupants. Effect of initiator, at the top of the foam-filled aluminum tube, different densities of rigid polyurethane foam, and number of annular rings under axial compression were described through energy absorption, crush force efficiency (CFE), and mass of structure. In order to verify the numerical results, a series of quasi-static axial compression tests was performed, and both load–displacement curves and deformation mechanism of the structure were analyzed. The results of multi-criteria decision analysis (MCDA), by incorporating numerical and experimental data, showed that in the considered material and geometry, the design with an initiator, four rings tube, and higher density of foam have superior performance in terms of energy absorption, CFE, and mass. More debate on effect of initiator would help to reach the simultaneous improved crashworthiness structure and lightweight design with greater degree of accuracy in the hope of reducing the occupant injury in a collision. [ABSTRACT FROM AUTHOR]

Knee prostheses as medical products require careful application of quality and design tool to ensure the best performance. Therefore, quality function deployment (QFD) was proposed as a quality tool to systematically integrate consumer’s expectation to perceived needs by medical and design team and to explicitly address the translation of customer needs into engineering characteristics. In this study, full factorial design of experiment (DOE) method was accompanied by finite element analysis (FEA) to evaluate the effect of inner contours of femoral component on mechanical stability of the implant and biomechanical stresses within the implant components and adjacent bone areas with preservation of the outer contours for standard Co-Cr alloy and a promising functionally graded material (FGM). The ANOVA revealed that the inner shape of femoral component influenced the performance measures in which the angle between the distal and anterior cuts and the angle between the distal and posterior cuts were greatly influential. In the final ranking of alternatives, using multicriteria decision analysis (MCDA), the designs with FGM was ranked first over the Co-Cr femoral component, but the original design with Co-Cr material was not the best choice femoral component, among the top ranked design with the same material. [ABSTRACT FROM AUTHOR]

Considerable effort has been spent on the development of normalization models in multi-attribute decision-making (MADM) but despite all of these there is no definitive answer to question: which technique is the most appropriate? Therefore, after a thorough review of the literature, thirty-one methods were identified, classified and evaluated for use in materials selection problems. The objective of this paper is to examine the shortcomings of normalization methods and suggest ways of improving their use in the engineering design decision-making process. The emphasis is placed on materials selection, for problems that include target criteria, as well as cost and benefit considerations, typically seen in more challenging applications such as aerospace and biomedical engineering. It is shown that although many normalization methods may appear to be minor variants of each other, these nuances can have important consequences in engineering design decision-making. To conclude, some dimensionless methods are proposed. The result of this research investigation will help ensure engineering decision makers in general improve their current use of MADM methods but in particular aid designers in developing suitable design performance indices for materials selection. [ABSTRACT FROM AUTHOR]

Considerable effort has been spent on the development of normalization models in multi-attribute decision-making (MADM) but despite all of these there is no definitive answer to question: which technique is the most appropriate? Therefore, after a thorough review of the literature, thirty-one methods were identified, classified and evaluated for use in materials selection problems. The objective of this paper is to examine the shortcomings of normalization methods and suggest ways of improving their use in the engineering design decision-making process. The emphasis is placed on materials selection, for problems that include target criteria, as well as cost and benefit considerations, typically seen in more challenging applications such as aerospace and biomedical engineering. It is shown that although many normalization methods may appear to be minor variants of each other, these nuances can have important consequences in engineering design decision-making. To conclude, some dimensionless methods are proposed. The result of this research investigation will help ensure engineering decision makers in general improve their current use of MADM methods but in particular aid designers in developing suitable design performance indices for materials selection. [ABSTRACT FROM AUTHOR]

Web services today are among the most widely used groups for Service Oriented Architecture (SOA). Service selection is one of the most significant current discussions in SOA, which evaluates discovered services and chooses the best candidate from them. Although a majority of service selection techniques apply Quality of Service (QoS), the behaviour of QoS-based service selection leads to service selection problems in Multi-Criteria Decision Making (MCDM). In the existing works, the confidence level of decision makers is neglected and does not consider their expertise in assessing Web services. In this paper, we employ the VIKOR (VIšekriterijumskoKOmpromisnoRangiranje) method, which is absent in the literature for service selection, but is well-known in other research. We propose a QoS-based approach that deals with service selection by applying VIKOR with improvement of features. This research determines the weights of criteria based on user preference and accounts for the confidence level of decision makers. The proposed approach is illustrated by an example in order to demonstrate and validate the model. The results of this research may facilitate service consumers to attain a more efficient decision when selecting the appropriate service. [ABSTRACT FROM AUTHOR]

Abstract: The selection of the most appropriate material, or combination of materials, is a demanding intellectual process that takes a lot of time and experience. There are a large number of established and newly developed materials, and their associated materials processes, necessitating the simultaneous consideration of many conflicting criteria. This has highlighted the importance of the developing field of multi-criteria decision-making (MCDM) to the material selection process which is especially useful for high technology market where product differentiation and competitive advantage are often achievable with just small gains in material performance. It is clear that decision-making techniques that address target criteria as well as cost and benefit criteria can help engineering designers make better informed choices of materials. Despite the progress has been made in the ranking of materials for target-based criteria, there is no formalized technique for calculating the weighting dependency when target criteria must be taken into account in material selection problems that usually deals with databases. Therefore, to overcome this shortcoming, the strategy of using dependent weightings is extended in this research. Also, an alternative method is proposed to incorporate the correlation, objective, and subjective weightings effectively when there is uncertainty in the importance of three types of weights. This issue is very important for inexperienced designers. The updated procedure is validated through biomedical applications. The first example demonstrates the importance of dependency weighting in amalgam tooth filling material selection and the second one is a hip joint prosthesis material selection problem, which includes target criteria. Furthermore, a model of continuous improvement in product development is outlined, and it is highlighted that the material selection/development is a permanent and endless task for sustainable and profitable growth. [Copyright &y& Elsevier]

Abstract: The problem with supporting decision-making to help choose materials in engineering design is that it needs different tools in different situations. This is because there is actually a range of values for any property of a given material and there are several methods in multi-attribute decision making (MADM) for ranking of alternatives based on interval data. Recently some MADM methods have been updated for materials selection that address target-based criteria, and validated using biomedical implant design applications. When data are not exact and target-based criteria available, the current methods must be modified to show the correct ranking of materials. Therefore, in this research a new VIKOR method for ranking materials with simultaneous availability of interval data and all types of criteria is presented. Three practical examples of materials selection, including biomedical implants, are presented to demonstrate the extended approach and its validity. It is shown that when there are no target criteria, the new method is the same as the conventional method. [Copyright &y& Elsevier]

Abstract: Ranking and selection of the optimal material is an important stage in the engineering design process. However, most of the methods proposed for ranking in materials selection have tended to focus on cost and benefit criteria, with target values receiving much less attention in spite of their importance in many practical decision-making problems such as selecting materials to best match the properties of human tissue in biomedical engineering applications. In response to this perceived gap, the development of a new normalization technique is considered in this paper that provides an extension of the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method and objective weighting in materials selection. There are four example cases included to validate the accuracy of outcomes from the proposed model. It is believed that the proposed decision-making model is suitable for linking to material databases and has the potential to enhance the efficiency of computer-aided materials selection systems. [Copyright &y& Elsevier]

Material selection is an onerous process of design activities which needs to be carefully carried out in order to increase the probability of success. A lot of multi-criteria decision-making methods have been proposed in material selection, many of which require quantitative weights for the attributes. Since weights play a very significant role in the ranking results of the materials, this paper presents a framework for determining importance degree of criteria to overcome the shortcomings of this subject in material selection. Furthermore, the suggested framework covers the situation of interdependent relationship between the criteria which has not been surveyed in material selection yet. An example was considered to illustrate how this framework is conducted. On the basis of the numerical results, it can be concluded that the proposed method can soundly deal with the material selection problems. [ABSTRACT FROM AUTHOR]

Abstract: Materials selection is an onerous but very important activity in the design process. An inappropriate choice of material(s) can adversely affect the productivity and profitability and hence reputation of a manufacturing organization. The complexity of materials selection makes multi-criteria analysis an invaluable tool in the engineering design process. However, the application of various multi-criteria decision making (MCDM) methods can yield different results, especially when alternatives lead to similar performance. Therefore, an aggregation technique is proposed in this paper for optimal decision-making. In this approach, ranking orders obtained by various MCDM methods are used as the input of the suggested procedure and the outputs are aggregation rankings, which help designers and engineers to reach a consensus on materials selection for a specific application. An illustrative example is given to demonstrate the application of this procedure and its effectiveness in obtaining optimal materials selection. [Copyright &y& Elsevier]

Abstract: The increasing trend of total knee replacement (TKR) revision surgery, which is associated with aseptic loosening, makes it a challenging research subject. The concern of loosening can be partially improved by selecting the optimal materials for TKR components. Therefore, this paper considers selection of the best material among the set of alternatives for femoral component of TKR through the multi-criteria decision making approach. The comprehensive VIKOR method was used to select the optimum material, and a systematic technique for sensitivity analysis of weights was introduced to find more reliable results. The obtained ranking order suggested the use of new materials over the existing ones. Porous and dense NiTi shape memory alloys were ranked first and second respectively. [Copyright &y& Elsevier]

Abstract: In engineering design, material alternatives evaluate according to different criteria depending on the objectives of the problem. Performance ratings for different criteria are measured by different units, but in the decision matrix in order to have a valid comparison all the elements must be dimensionless. However, a lot of normalization methods have been developed for cost and benefit criteria, not only there has not been enough attention for engineering design situations in which approaching the target values are desirable but also the available methods have shortcomings. A new version of VIKOR method, which covers all types of criteria with emphasize on compromise solution, is proposed in this paper. The proposed comprehensive version of VIKOR also overcomes the main error of traditional VIKOR by a simpler approach. Suggested method can enhance exactness of material selection results in different applications, especially in biomedical application where the implant materials should possess similar properties to those of human tissues. Five examples are included to illustrate and justify the suggested method. [ABSTRACT FROM AUTHOR]

Abstract: Ranking and choosing the best material is one of most important stages in material selection process. Using linear assignment method, the multi-criteria decision making (MCDM) approach is proposed in decision-making process to rank the materials for a given engineering component with respect to several criteria. The proposed material selection procedure is relatively simple, and can be a useful approach when material selection problem includes qualitative properties or user-interaction aspects. The suggested approach also can be use for quantitative properties. Three examples are included to demonstrate the suggested method. Result of proposed approach showed good agreement with other methods. [Copyright &y& Elsevier]

Abstract: We study basic properties of monomial ideals with linear quotients. It is shown that if the monomial ideal I has linear quotients, then the squarefree part of I and each component of I as well as have linear quotients, where is the graded maximal ideal of the polynomial ring. As an analogy to the Rearrangement Lemma of Björner and Wachs we also show that for a monomial ideal with linear quotients the admissible order of the generators can be chosen degree increasingly. [Copyright &y& Elsevier]

Abstract: We show that an arbitrary monomial ideal I is pretty clean if and only if its polarization is clean. This yields a new characterization of pretty clean monomial ideals in terms of the arithmetic degree, and it also implies that a multicomplex is shellable if and only the simplicial complex corresponding to its polarization is (non-pure) shellable. We also discuss Stanley decompositions in relation to prime filtrations. [Copyright &y& Elsevier]

Introduction: Mild cognitive impairment (MCI) is a progressive age-related condition caused by physiological and structural changes in the brain, such as neurodegeneration and hypometabolism. Transcranial photobiomodulation (tPBM) is a neuromodulation technique that improves brain metabolism and oxygenation by irradiating red to near-infrared light on a specific area of the head. This study aimed to investigate the effect of multi-session tPBM on the cognitive capacities and attentional function of older women with MCI. Material and methods: In this randomized controlled trial, 42 older women with MCI were randomly assigned to 2 equal groups: real and sham. The mini-mental state examination (MMSE) and the attentional Go/No-Go task were used to examine the patients. On the right frontal-pole of the cortex, 5 sessions of 850 nm tPBM were given. Re-examinations were conducted on the participants. For the Go/No-Go task, the reaction time to the target (RTT), the percentage of correct trials (PCT), and the efficiency score (ES) were measured. Results: The findings revealed a significant interaction between group x time for MMSE (F (1, 40) = 20, p < 0.001, η² = 0.33), and the post-hoc paired-samples f-tests revealed a substantial rise in the mean MMSE in the real group (f = 15.9; p = 0.001; d = 9.3). Additionally, for ES (F (1, 40) = 19, p < 0.001, η² = 0.32), RTT (F (1, 40) = 17, p < 0.001, η² = 0.38), and PCT (F (1, 40) = 13, p < 0.001, η² = 0.31), a significant group x time interaction was discovered, and post-hoc paired-samples f-tests revealed a significant improvement in attention performance of the real group for increases in the mean of ES (F (1,40) = 20, p < 0.001, η² = 0.33), (f = 5.3, p < 0.001,d = 0.034), decreases in the mean of RTT (f = 4.8; p = 0.001; d = -37.4), and increases in the mean of PCT (f = 2.67; p = 0.015; d = 6.3) Conclusions: According to the findings of this study, tPBM had a positive effect on older people's attention and cognitive abilities. [ABSTRACT FROM AUTHOR]

The purpose of this single subject study was to investigate whether transcranial direct current stimulation (tDCS) applied to both hemispheres combined with speech therapy can improve language learning in a pair of 5-year-old twins with corpus callosum dysgenesis (CCD). The treatment protocol included anodal tDCS with simultaneous speech therapy in one of the participants (T.D.), and sham-tDCS with the same montage, and stimulation regime concomitant with speech therapy for the other twin (A.D.). Our findings show that T.D. improved in language production when treated with speech therapy in combination with tDCS. A.D. showed evidence for a relatively minor behavioral benefit from speech therapy. [ABSTRACT FROM AUTHOR]

Focuses on the early detection of cancers throughout the gastrointestinal tract using compact endoscopic imaging systems. Incorporation of certain devices into the imaging system; Confirmation of the optical contrast in resected specimen; Consideration of fluorescence diagnosis as a cancer identification method.

Aim: Math skill is a basic need for an individual, as a career prospect. However, little is known about early brain processes of arithmetic between individuals with different math skill. Therefore, we questioned the modulation of the amplitude of an early negative component by math skill level in an arithmetic verification paradigm using event‐related potential (ERP). Methods: Thirty‐six right‐handed participants were assigned in two groups of high‐ and low‐performing students. Their electroencephalogram was recorded while they completed an arithmetic verification task. Simple arithmetic operands were made by random digits from 1 to 9. Addition and subtraction operations were equally used in correct and incorrect responses. The accuracy scores, reaction times, and peak amplitude of the negativity in 200‐400 ms time window were analyzed. Results: The high‐performing group showed significantly higher response speeds, and they were more accurate than the low‐performing group. The group × region interaction effect was significant. The high‐performing group showed a significantly greater negativity, particularly in parietal region, while the low‐performing group showed a significantly deeper negativity in frontal and prefrontal region. In the low‐performing group, there were significant peak amplitude differences between the anterior and posterior areas. However, such differences were not detected in the high‐performing group. Conclusion: Students with different mathematical performance showed distinct patterns in early processing of arithmetic verification, as reflected by differences in negativity at 200‐400 ms at anterior and posterior. This suggests that ERPs could be used to differentiate math mastery at neural level which is beneficial in educational and clinical contexts. [ABSTRACT FROM AUTHOR]

The optimum design for energy absorbers requires considering different criteria. Therefore, the design process can benefit from Multiple-Attribute Decision-Making (MADM) approach. Thin-walled structures can be particularly employed as energy absorbers in automobiles to dissipate energy and protect passengers from the peak crush load caused by severe collisions. The present study investigates a thin-walled conical segmented aluminum tube which consists of several circular sections with different thicknesses. To achieve the optimum design, a number of conical segmented tubes were modeled by finite element method. Energy absorption, initial peak load, crush force efficiency (the ratio of mean load to maximum load), mass of the structure and deformation type as the conflicting objective functions were defined as attributes/criteria. The numeric logic (NL) technique was applied to determine the weight of various criteria. Furthermore, the MULTIMOORA method, as a well-accepted MADM model, was utilized to obtain the optimum design for a conical segmented tube. The design variables included wall thickness, lengths of sections, and taper angle. Drawing a comparison between the top rank conical segmented tube and the top rank conical simple tube revealed that the conical segmented tube could increase the efficiency of the crush load up to 23.8% and reduce the initial peak load and mass of the tube up to 54% and 17.54%, respectively. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented regarding the role of nonword repetition task (NRT) in examining the phonological loop of people with schizophrenia.

Na+/H+ Exchanger Regulatory Factor-1 (NHERF1) is a scaffolding protein containing 2 PDZ domains that coordinates the assembly and trafficking of transmembrane receptors and ion channels. Most target proteins harboring a C-terminus recognition motif bind more-or-less equivalently to the either PDZ domain, which contain identical core-binding motifs. However some substrates such as the type II sodium-dependent phosphate co-transporter (NPT2A), uniquely bind only one PDZ domain. We sought to define the structural determinants responsible for the specificity of interaction between NHERF1 PDZ domains and NPT2A. By performing all-atom/explicit-solvent molecular dynamics (MD) simulations in combination with biological mutagenesis, fluorescent polarization (FP) binding assays, and isothermal titration calorimetry (ITC), we found that in addition to canonical interactions of residues at 0 and -2 positions, Arg at the -1 position of NPT2A plays a critical role in association with Glu43 and His27 of PDZ1 that are absent in PDZ2. Experimentally introduced mutation in PDZ1 (Glu43Asp and His27Asn) decreased binding to NPT2A. Conversely, introduction of Asp183Glu and Asn167His mutations in PDZ2 promoted the formation of favorable interactions yielding micromolar KDs. The results describe novel determinants within both the PDZ domain and outside the canonical PDZ-recognition motif that are responsible for discrimination of NPT2A between two PDZ domains. The results challenge general paradigms for PDZ recognition and suggest new targets for drug development. [ABSTRACT FROM AUTHOR]

Background: Exposure to small confined spaces evokes physiological responses such as increased heart rate in claustrophobic patients. However, little is known about electrocortical activity while these people are functionally exposed to such phobic situations. The aim of this study was to examine possible changes in electrocortical activity in this population. Method: Two highly affected patients with claustrophobia and two healthy controls participated in this in vivo study during which electroencephalographic (EEG) activity was continuously recorded. Relative power spectral density (rPSD) was compared between two situations of being relaxed in a well-lit open area, and sitting in a relaxed chair in a small (90 cm × 180 cm × 155 cm) chamber with a dim light. This comparison of rPSDs in five frequency bands of EEG was intended to investigate possible patterns of change in electrical activity during fear-related situation. This possible change was also compared between claustrophobic patients and healthy controls in all cortical areas. Results: Statistical models showed that there is a significant interaction between groups of participants and experimental situations in all frequency bands (P < 0.01). In other words, claustrophobic patients showed significantly different changes in electrical activity while going from rest to the test situation. Clear differences were observed in alpha and theta bands. In the theta band, while healthy controls showed an increase in rPSD, claustrophobic patients showed an opposite decrease in the power of electrical activity when entering the confined chamber. In alpha band, both groups showed an increase in rPSD, though this increase was significantly higher for claustrophobic patients. Conclusion: The effect of in vivo exposure to confined environments on EEG activity is different in claustrophobic patients than in healthy controls. Most of this contrast is observed in central and parietal areas of the cortex, and in the alpha and theta bands. [ABSTRACT FROM AUTHOR]

Aims: Verbal Fluency is sensitive to brain damage and is employed to assess language abilities like the size of vocabulary and the semantic‐lexical networks' integrity and executive functioning abilities particularly inhibition, working memory, and self‐monitoring. Various studies revealed oscillatory changes related to word retrieval during different tasks. However, there are not enough studies on electroencephalographic characteristics of word retrieval routes (phonological or semantic pathway) during free recall. The purpose of our study was to investigate electroencephalography power relationship with semantic and phonological word finding routes during verbal fluency. Methods: In this within‐subject study, the electroencephalography of 20 healthy participants was recorded during written category and letter fluency tasks and compared with the rest state. Absolute power of the signals in delta (1‐3.5 Hz), theta (4‐7.5 Hz), alpha (8‐12 Hz), and beta (12.5‐30 Hz) was calculated in three lobes (frontal, parietal, and temporal). Results: A repeated measures ANOVA showed significant interaction of condition × lobe × frequency × side (P <.001). Post hoc test for each lobe showed significant changes in the absolute power of delta, theta and beta for frontal, delta and theta for parietal, and theta and beta for temporal lobes (P‐values <.05). Conclusion: Searching the words by phonological entries is associated with decreased beta and increased theta in left frontal lobe. These changes are not necessary for semantic word retrieval strategy. [ABSTRACT FROM AUTHOR]

In this paper, we introduce a family of monomial ideals with the persistence property. Given positive integers n and t , we consider the monomial ideal I = Ind t (P n) generated by all monomials x F , where F is an independent set of vertices of the path graph P n of size t , which is indeed the facet ideal of the t th skeleton of the independence complex of P n . We describe the set of associated primes of all powers of I explicitly. It turns out that any such ideal I has the persistence property. Moreover, the index of stability of I and the stable set of associated prime ideals of I are determined. [ABSTRACT FROM AUTHOR]

Highlights: [•] Concurrent material and geometry optimization of femoral component pegs. [•] Multi-objective design approach for reduction of stress shielding effect. [•] Target-based criteria in design selection. [•] Peg design in FGM femoral component. [ABSTRACT FROM AUTHOR]

Highlights: [•] FGM optimization for femoral component in total knee replacement. [•] Multi-objective material design. [•] Combination of FEA–MCDM–RSM. [ABSTRACT FROM AUTHOR]

Abstract: The multi-domain scaffolding protein NHERF1 modulates the assembly and intracellular trafficking of various transmembrane receptors and ion-transport proteins. The two PDZ (postsynaptic density 95/disk large/zonula occluden 1) domains of NHERF1 possess very different ligand-binding capabilities: PDZ1 recognizes a variety of membrane proteins with high affinity, while PDZ2 only binds limited number of target proteins. Here using NMR, we have determined the structural and dynamic mechanisms that differentiate the binding affinities of the two PDZ domains, for the type 1 PDZ-binding motif (QD T R L ) in the carboxyl terminus of cystic fibrosis transmembrane regulator. Similar to PDZ2, we have identified a helix–loop–helix subdomain coupled to the canonical PDZ1 domain. The extended PDZ1 domain is highly flexible with correlated backbone motions on fast and slow timescales, while the extended PDZ2 domain is relatively rigid. The malleability of the extended PDZ1 structure facilitates the transmission of conformational changes at the ligand-binding site to the remote helix–loop–helix extension. By contrast, ligand binding has only modest effects on the conformation and dynamics of the extended PDZ2 domain. The study shows that ligand-induced structural and dynamic changes coupled with sequence variation at the putative PDZ binding site dictate ligand selectivity and binding affinity of the two PDZ domains of NHERF1. [Copyright &y& Elsevier]

This study aimed to assess the reliability and validity of the Persian version of the Pediatric Voice Handicap Index (pVHI). The questionnaire was translated into Persian and then administrated to the parents of 45 dysphonic children and parents of 135 normal children. The content validity of the questionnaire was confirmed by eight speech-language pathologists. Internal consistency and test-retest reliability were measured via Cronbach's alpha and intra-class correlation coefficient, respectively. Independent-samples t -test was used to evaluate the discriminative and clinical validity of Persian pVHI. Cronbach's coefficient values were excellent for the total score (α = 0.94) and physical subcomponent (α = 0.91). Moreover, these corresponding values were satisfactory for functional (α = 0.82) and emotional (α = 0.79) subcomponents. Test-retest reliability for the total score was high in both dysphonic and control groups (intra-class correlation coefficient> 0.92). There were significant differences between the control and dysphonic groups in terms of the total score and all subcomponents scores of Persian pVHI. However, no significant difference was observed in the mean total score of the Persian pVHI between the control and dysphonic group regarding gender (P < 0.001). Persian version of pVHI is a valid and reliable tool to evaluate the severity of voice disorder and its negative effects on the daily life of Persian children with voice disorder from the Parents' viewpoint. [ABSTRACT FROM AUTHOR]