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In many applications of notch filtering, short transient response and high quality factors are very important issues. Increasing Q factor, decreases the bandwidth and improves magnitude selectivity near the notch frequency, but unfortunately increases the transient duration of the response. Recently, time-variant methods using exponential or sigmoid functions are considered to enhance the notch filter performance. In this paper, conventional and feedback-structured notch filters (following a recent work by Pei et al) are investigated in details. Using feedback structure, anyone can obtain a good narrow-band notch filter by tuning the feedback gain. However, it suffers from a long transient duration. In order to improve the performance of the filter, a new simple time-variant method to control the pole-position is introduced. Proposed method can keep the pole radius in the minimum value to decrease the transient duration more efficiently than other recently-reported ones as Piskorowski, Li and Rana methods. Also, it drives the pole to approach the unit circle or final position rapidly, normally after a few samples, while attaining a narrow bandwidth. In this paper, the performance of the proposed filter is compared with Piskorowski, Li and Rana methods. Simulation results show that the proposed algorithm can improve the performance of the feedback-structured filter compared to other methods. The results demonstrate superior performance of the presented method not only in accordance with power line interference, but also in removing the distortion of the time-variant filters.

The functionality of psyllium hydrocolloid gel (PHG, 0.1–0.75%) to improve physicochemical (pH, syneresis, physical stability and lightness), rheological (viscosity and flow behavior), microstructural and sensorial characteristics of an ethnic acid-fermented dairy product “Kashk” with different contents of dried Kashk powder (DKP, 15–25%) was investigated. Results showed the low-viscous liquid Kashks containing 0.1% PHG at all DKP levels had the highest syneresis, instability and lightness amounts. Scanning electron microscopy and laser diffraction particle size analysis exhibited the increasing PHG content by 0.5% reduced aggregated particles size in a uniform monomodal distribution, whereas the weaker interaction of polysaccharide-casein at 0.75% PHG led to an increase in the number of unadsorbed polysaccharides. A highly negative correlation was also found between the viscosity and phase separation percentage, and between the particles size and overall acceptability sensory attribute. According to the quality evaluations, the best formulation was composed of 25% DKP and 0.5% PHG.

The authors propose a dual mode transmit diversity (TD) scheme switching between co-located TD (CTD) and distributed TD (DTD) based on the quasi-static channel parameters. The authors first compare CTD and DTD according to spatial correlation coefficient (SCC) of CTD and distributed mean channel gain (MCG) of DTD. By using asymptotic bit error rate (BER) formula, the authors derive a compact and very accurate border equation of DTD-preferred and CTD-preferred regions in MCG ratio and SCC space. Based on the derived border, the authors propose a dual mode TD scheme switching between CTD and DTD according to MCG ratio and SCC. It is shown that the signal-to-noise ratio (SNR) gain contours and the border line for TD switching are irrespective of SNR and modulation scheme. The results show that the proposed dual mode scheme outperforms the single modes not only in the location-specific performance but also in the averaged performance over the cell area. In the averaged BER over the entire cell area, performance improvement of the dual mode scheme over CTD is significant if SCC is roughly larger than 0.6 irrespective of cell shape, spatial correlation model of CTD, path loss exponent and shadowing model.

Distributed transmit diversity (DTD) technique that combines cooperative communications and diversity techniques is a suitable solution in 5th-generation (5G) systems. In this paper, we investigate the effect of receiver phase compensation (RPC) on the performance of DTD. We introduce new expressions for the average error rate of DTD in the presence of RPC. The derived expressions are useful for a large number of modulation schemes. We obtain further insights by comparing the RPC effect on DTD with different spatially correlated collocated transmit diversity (CTD). The new observations include the following: (1) In the case of feedback delay, the phase compensation (PC) is required on the receiver side in addition to the transmitter side. (2) In DTD with RPC, the system performance is improved by increasing the differences between the channel gain variances. However, this is the opposite of the case of DTD without RPC. (3) The correlated CTD is more sensitive to RPC than DTD. This sensitivity increases by enhancing the correlation between transmit (TX) antennas. (4) In the case where there is no delay for CTD or DTD, RPC does not affect the system’s performance.

Research has highlighted the role of working memory and inhibition on the performance of pupils in mathematics. This study was an attempt to look into the relationship between executive function including working memory capacity and inhibition on the one hand and mathematical abilities on the other. 30 primary school students were selected from among the 4th graders, forming two groups of students with high achievement in mathematics (strong) and those with low achievement in mathematics (poor) with the closes possible reading ability and IQ. The two groups were compared with regards to working memory, which was measured via Wechsler intelligence test, and inhibition, which was measured using the Stroop test. The data collected for these measures were analyzed using ANOVA. The results of the T test showed that the poor group performance on inhibition and working memory was significantly lower than strong group. The findings indicate the importance of these actions (inhibition and working memory) on math performance of students.

Background: Upper extremity is the most common part of the body, which is exposed to injuries with physical, mental, social and economic consequences. Objectives: This research studied the prevalence and types of personality disorders in patients with upper extremity trauma at Hazrat Fatima hospital. Methods: This research studied all patients with upper extremity trauma in a three-month period hospitalized at Hazrat Fatemeh. The Millon Test was filled by all candidates with a clinical psychologist and psychometric supervision. Results were analyzed statistically. Results: This study included 202 male participants with age range of 14 to 70 years old, amongst whom 41.4% had personality disorders. The prevalence of personality disorder in violence and self-injury groups was 72.7% and 39.3% in the group of industrial accidents, which proved a significant dierence (P = 0.003). Avoidant personality disorders (P = 001), narcissistic (P = 0.003), anti-social (P = 0.002), borderline (P = 0.001) passive aggressive (P = 0.002) were significantly more common in violence and self-injury group. Conclusions: The present study revealed that the prevalence of personality disorder in patients with upper extremity injuries is more than the society. Due to the high rate of personality disorder in hand trauma victims, we recommended routine psychological evaluation of these patients.

In this paper, the effect of feedback delay and channel gain difference (CGD) on the performance of distributed transmit diversity (DTD) systems are analyzed over Rayleigh fading channels. We derive new expressions for the average error rate of DTD in the absence of receiver phase compensation (RPC), which is useful for a large number of modulation schemes. Furthermore, we analyze the effect of feedback delay and CGD on DTD compared to spatially correlated co-located transmit diversity (CTD) systems. Analytical results enable us to verify the fact that in DTD without RPC as CGD between antennas increases the performance degrades. Via extensive performance evaluations for various cases, we quantitatively analyze the sensitivity of the performance gap between CTD and DTD in absence of RPC according to feedback delay. The results show that, in without RPC case DTD is robust to feedback delay compared to correlated CTD. We also present Monte Carlo simulation results as verification of our analytical results.

Background The use of autologous nerve material has become the gold standard for reconstructing peripheral nerve defects. For various applications, nerve grafting is required to restore nerve continuity, and the sural nerve may be considered the best option for such purposes. The aim of this study was to quantitatively assess the recovery of donor site sensory deficit following sural nerve harvest. Methods This descriptive study was performed on 30 patients in the first week after surgery and 23 patients 1 year after sural nerve harvest. Mapping of the affected area was performed using Semmes–Weinstein monofilaments. Then, the areas of diminished or loss of sensation were evaluated with monofilament test, static and dynamic two-point discrimination, and temperature sensitivity. Also, the complaints of paresthesia, numbness, and pain were measured. The results were compared in the two groups. Results The area of diminished or loss of sensation 1 week after surgery was significantly reduced after 1 year (p00.000). A reduction was observed in the patients' complaints, especially in numbness and paresthesia, and better results were obtained in clinical findings, significantly in dynamic two-point discrimination and temperature sensation. Conclusion In this study, donor site adverse effects of sural nerve harvest decreased over time, and improvements in sensory tests were observed; however, more studies should be performed on this topic. Level of Evidence: Level III, diagnostic study.

The performance of transmit beamforming (BF) systems in terms of the spatial correlation coefficient and channel gain variance (CGV) are analyzed over Rayleigh fading channels. We derive bit error rate (BER) of distributed BF (DBF) systems as a function of CGV of distributed channel links. As for clustered BF (CBF), we express its BER as the explicit function of the correlation coefficient. Based on the BER formulas, the required transmit signal-to-noise ratios (SNRs) for target BERs are derived in DBF and CBF as another performance measure. Using these expressions, the performance of DBF is compared with the spatially correlated CBF systems on CGV and correlation coefficient plane. Analytical results enable us to verify the fact that if one of the distributed antennas has significantly larger CGV than the others, it is better to employ CBF rather than DBF and vice versa. As the correlation among the CBF antennas increases, the area where DBF performs better increases. Via extensive performance evaluations for various cases, we quantitatively analyze the sensitivity of the performance gap between CBF and DBF according to the CGV ratio of DBF and the spatial correlation of CBF. The overall performance trends of CBF and DBF are almost the same irrespective performance measures, i.e., BER or required transmit SNRs. It is remarkable that the BER gap is almost invariant to SNRs and the required SNR gap is almost invariant to the target BER. We perform Monte Carlo simulations to verify the analytical results.

Aim: The aim of the present study is to determine the effectiveness of positive psychotherapy on the happiness and gratitude among female students of the University of Isfahan in the academic year 2013–2014. Methodology: The design of the present study is quasi-experimental with the control group and pretest-posttest and follow-up test. For sampling among 100 female girls who registered for this study, a number of 30 individuals who were lacking in any symptom of severe psychological disorders or character disorders in the first and second axes of diagnostic and statistical manual of mental disorders-IV-Text review were selected. Then, this number were randomly divided into two control and experimental group each with 15 participants. The instruments used for collecting data included the positive psychotherapy questionnaire and the gratitude questionnaire-six item form. In the experimental group, positive psychotherapy sessions were held in group in 10 sessions. However, the control group received no intervention. To analyze the data of the present study, ANCOVA and SPSS-17 software were used. Results: The results indicated that the positive psychotherapy is effective on the increase of overall happiness and the components of pleasant, engaged, and meaningful life in the stages of posttest and follow-up (P < 0.05), although this effectiveness is confirmed on the component of meaningful life in the posttest. In addition, in the domain of gratitude, the members of the experimental group indicated a significant increase in their scores in the stages of posttest and follow-up as compared to the control group (P < 0.05). Conclusion: From the findings obtained from this study, it can be concluded that, in general, positive psychotherapy is effective on the increase of overall happiness and its components and gratitude of female students in the University of Isfahan. Therefore, the positive psychotherapy is an appropriate alternative for increasing happiness and gratitude of students.

The performances of distributed beamforming (BF) with feedback delay have been evaluated for the several scenarios of the distributed channel gain differences. The performance degradations by feedback delay and by using codebook-based BF are analyzed according to the channel gain difference. As the most complexity-reduced alternative, selective power allocation (PA) is also compared with the full feedback-based BF and the codebook-based BF. Based on the results, we note several distinguishable behavior of the distributed BF compared to the clustered BF. 1) Large differences among the channel gains (most typical scenario of distributed BF) suppress the feedback delay effect on performance degradation compared to the case of no differences among the channel gains (similar to the case of clustered BF). 2) However, performance degradation by codebook-based BF becomes more severe in the case of large differences among the channel gains compared to the case of small differences among the channel gains irrespective of feedback delay. With large differences among the channel gains, codebook-based BF gets even worse than the selective PA in distributed BF. 3) For the case of large differences among the channel gains, selective PA is a good alternative to the full feedback-based BF. However, this is only for the case of small feedback delay. The performance gap becomes non-negligible as the feedback delay increases. On the other hand, for the case of no or small channel gain differences, selective PA is a good alternative to the full feedback-based BF as the feedback delay increases.

Although the recognition results of support vector machines(SVM) are very promising in many applications, there is a gap between the accuracy of SVM based speech recognizers and time series models (e.g. hidden Markov model) in speech recognition. The main reasons are the lack of proper methods to classify the acoustic units into more than two classes and suitable SVM based sequence decoders. This paper describes a trainable method for SVM multi-class classification based on confidence measures of the sets of two-class SVM classifiers using an artificial neural network. In addition, a pruning method has been proposed for SVM multi-class classification to decrease the computational complexity without significant decrease in accuracy. Also, a method has been proposed for time series recognition of the feature vectors of an utterance based on SVM classifiers. The experiments have been conducted on a set of confusable phonemes using TIMIT corpus. The results of the first method show 10% and 6% relative improvements in the recognition rate in comparison to one-versus-one and Kruger methods respectively for /b/, /d/ and /g/ phonemes. In addition, it is empirically deduced that the proposed phoneme classification framework yields significantly better classification rates than classic voting method. Comparing phoneme classification results of the proposed method with one-versus-one method indicate a 26% improvement in the classification rate for /b/, /d/ and /g/ phonemes.