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Use of synthetic dyes for dyeing of textile fabrics is most problematic environmental concerned for textile industry. The demand of natural colourants for the dyeing of textile fabrics has been increasing. Thus, sustainable novel technologies for textile dyeing are needed that utilize improved colour strength and enhanced performance characteristics of the fabric. This study attempts to highlight the possibility of using cochineal natural dye in the printing of polyester fabrics after surface modification by O2/Ar plasma treatment. The colour strength, air permeability, crease recovery angle of printed fabrics, colour fastness to rubbing, washing and light, were also studied. The surfaces of untreated and plasma-treated polyester fabrics were analysed by SEM to compare the morphological changes. Surface roughness and cracks were indicated after the plasma pretreatment. The results indicated that plasma treatment could improve the printability of polyester fabric compared with untreated samples, with enhanced the adhesion and penetration of printing paste to the surface. The air permeability of printed fabrics has decreased, while the angle of crease recovery has increased. The fastness properties of printed samples were found suitable to very good.

The evolution of a two-phase, air and unsaturated water vapor, time decaying, shearless, turbulent layer has been studied in the presence of both stable and unstable perturbations of the normal temperature lapse rate. The top interface between a warm vapor cloud and clear air in the absence of water droplets was considered as the reference dynamics. Direct, 3D numerical simulations were performed within a 6m x 6m wide and 12m high cloud portion, which was hypothesized to be located close to an interface between the warm cloud and clear air. The Taylor micro-scale Reynolds' number was 250 inside the cloud portion. The squared Froude's number varied over intervals of [0.4; 1038.5] and [-4.2; -20.8]. A sufficiently intense stratification was observed to change the mixing dynamics. The formation of a sub-layer inside the shearless layer was observed. The sub-layer, under a stable thermal stratification condition, behaved like a pit of kinetic energy. On the other hand, it was observed that kinetic energy transient growth took place under unstable conditions, which led to the formation of an energy peak just below the center of the shearless layer. The scaling law of the energy time variation inside the interface region was quantified: this is an algebraic law with an exponent that depends on the perturbation stratification intensity. The presence of an unstable stratification increased the differences in statistical behavior among the longitudinal velocity derivatives, compared with the unstratified case. Since the mixing process is suppressed in stable cases, small-scale anisotropy is also supressed., Comment: Turbulent transport, thermal stratification, stability, initial value problem, passive scalar

Emotion is an intense mental experience often manifested by rapid heartbeat, breathing, sweating, and facial expressions. Emotion recognition from these physiological signals is a challenging problem with interesting applications such as developing wearable assistive devices and smart human-computer interfaces. This paper presents an automated method for emotion classification in children using electrodermal activity (EDA) signals. The time-frequency analysis of the acquired raw EDAs provides a feature space based on which different emotions can be recognized. To this end, the complex Morlet (C-Morlet) wavelet function is applied on the recorded EDA signals. The dataset used in this paper includes a set of multimodal recordings of social and communicative behavior as well as EDA recordings of 100 children younger than 30 months old. The dataset is annotated by two experts to extract the time sequence corresponding to three main emotions including “Joy”, “Boredom”, and “Acceptance”. The annotation process is performed considering the synchronicity between the children's facial expressions and the EDA time sequences. Various experiments are conducted on the annotated EDA signals to classify emotions using a support vector machine (SVM) classifier. The quantitative results show that the emotion classification performance remarkably improves compared to other methods when the proposed wavelet-based features are used.

BACKGROUND: MicroRNAs (miRNAs) are endogenous, 18-22 nucleotide non-coding RNA molecules. Human cytomegalovirus (HCMV) is a ubiquitous and particular herpes virus that encodes miRNAs, which increases gradually in the presence of infection. One of the important viral miRNAs is HCMV-miRUL-148D, which plays a role in establishing and maintaining viral latency. OBJECTIVE: The current study aimed to evaluate the expression levels of HCMV-miRUL-148D in active and inactive HCMV infected transplant patient groups compared to healthy individuals. METHODS: Total RNA was extracted from blood samples of 60 solid organ transplant patients and 30healthy controls. In-house SYBR Green Real-Time PCR evaluated the expression levels of studied miRNAand gene. RESULTS: The expression level of the UL-148D gene was significantly higher in the active HCMV infectedpatients (p=0.001) compared to other groups. While the miRUL-148D expression level significantly increased in the inactive HCMV-infected patients (p

Background:The margin consensus guideline for patients undergoing primary breast conserving surgery (BCS) and whole breast radiotherapy defines a negative margin as no tumor on ink and concludes that wider margins do not improve local recurrence (LR) rates. There are few studies examining BCS margin width after neoadjuvant chemotherapy (NAC).We sought to determine the impact of margin width on LR and survival rates after NAC and BCS. Methods: Institutional database were reviewed to identify patients with stage I-III breast cancer treated with NAC and BCS from 2002-2014. Patients with inflammatory breast cancer were excluded. Chart review was performed to collect detailed patient and treatment factors. Margins widths were collected as reported and grouped as: positive (ink on tumor), close (2mm), for the purposes of this analysis. Cox regression was used to determine the relationship between margin width and local recurrence, disease free survival (DFS) and overall survival (OS). Result: 395 patients underwent NAC followed by BCS during the study period. The result was same as below. results Patients, n (%)Age at diagnosis (yrs)51 [22;79]Initial tumor size (cm)3.0 [0.6;11.0]Clinical node status - negative207 (52.4%)- positive188 (47.6%)subtype - HR-/Her2-148 (37.5%)- HR-/Her2+48 (12.2%)- HR+/Her2-124 (31.4%)- HR+/Her2+72 (18.2%)- unclassified3 ( 0.8%)pCR* status - pCR97 (24.6%)- non pCR295 (74.7%)- unclassified3 ( 0.8%)Final margin state - no residual tumor in breast108 (27.3%)- positive8 ( 2.0%)- close (≤2)99 (25.1%)- negative (>2)180 (45.6%)*pCR was defined as no invasive or in situ disease in breast and no tumor in axillary node Median patient age was 51 yrs (range 22-79); median tumor size at presentation was 3.0 cm (range 0.6-11.0) and 188 (47.6%) patients (pts) presented with clinically node positive disease. Breast cancer subtypes included 148 (37.5%) pts with HR-/Her2-, 48 (12.2%) pts with HR-/Her2+, 124 (31.4%) pts with HR+/Her2- and 72 (18.2%) pts with HR+/Her2+, disease. Among all patients the pCR rate, defined as no invasive or in situ disease, in the breast was 27.3% (108/395) and the pCR rate in the breast and axillary nodes was 24.6% (97/395). Final margin status included 8 (2.0%) pts with positive margins, 99 (25.1%) with close 2mm) margins. Among the patients with “positive margins”; all were noted to be posterior or anterior and the surgeon noted that re-excision was not possible. At a median follow-up of 53.0 months the LR rate was 2.8% and DFS was 87.4%. On cox regression, HR positive subtype (p=0.048), pCR (p=0.035), and pathologic negative node (p2mm margin groups. Conclusion: In this cohort of patients treated with NAC followed by BCS, LR rates were very low and there was no difference in DFS between patients with margins < 2mm or > 2mm. Further studies are needed to confirm the effect of margin width in the NAC setting. Citation Format: Choi J, Golshan M, Hu J, Gagnon HC, Densantis S, Barry B, King T. Margins in breast conserving surgery after neoadjuvant therapy [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-08-07.

This paper presents the results of our recent work on studying the effects of deep brain stimulation (DBS) and medication on the dynamics of brain local field potential (LFP) signals used for behavior analysis of patients with Parkinson s disease (PD). DBS is a technique used to alleviate the severe symptoms of PD when pharmacotherapy is not very effective. Behavior recognition from the LFP signals recorded from the subthalamic nucleus (STN) has application in developing closed-loop DBS systems, where the stimulation pulse is adaptively generated according to subjects performing behavior. Most of the existing studies on behavior recognition that use STN-LFPs are based on the DBS being off. This paper discovers how the performance and accuracy of automated behavior recognition from the LFP signals are affected under different paradigms of stimulation on/off. We first study the notion of beta power suppression in LFP signals under different scenarios (stimulation on/off and medication on/off). Afterward, we explore the accuracy of support vector machines in predicting human actions (button press and reach) using the spectrogram of STN-LFP signals. Our experiments on the recorded LFP signals of three subjects confirm that the beta power is suppressed significantly when the patients take medication (p-value, 40th IEEE International Conference on Engineering in Medicine and Biology (IEEE EMBC), Honolulu, Hawaii, July 17-21, 2018

Classification of human behavior is key to developing closed-loop Deep Brain Stimulation (DBS) systems, which may be able to decrease the power consumption and side effects of the existing systems. Recent studies have shown that the Local Field Potential (LFP) signals from both Subthalamic Nuclei (STN) of the brain can be used to recognize human behavior. Since the DBS leads implanted in each STN can collect three bipolar signals, the selection of a suitable pair of LFPs that achieves optimal recognition performance is still an open problem to address. Considering the presence of synchronized aggregate activity in the basal ganglia, this paper presents an FFT-based synchronization approach to automatically select a relevant pair of LFPs and use the pair together with an SVM-based MKL classifier for behavior recognition purposes. Our experiments on five subjects show the superiority of the proposed approach compared to other methods used for behavior classification., IEEE Conf on ICASSP 2017

Residual elastic strain in a thin slice parted off from a laser shock peened plate of titanium alloy Ti–6Al–4V was measured using high-energy diffraction on station 16.3 at SRS Daresbury. Diffraction peaks were collected for reflections (00.2), (10.1), (10.2), and (11.0) from the hcp (hexagonal close-packed) α-phase of the titanium alloy. Reference values of the lattice spacing for each of the reflections were found from the diffraction pattern collected from a stress-free sampling volume. The residual elastic strain values calculated on the basis of each reflection were then computed and plotted as a function of distance from the treated surface. Residual strain profiles show significant differences, reflecting the variation in the elastic and plastic with orientation of the grain, i.e. anisotropy. The average macroscopic residual elastic strain was therefore computed using an appropriate average, taking into account multiplicity of each reflection. Since the greatest contrast in elastic and plastic properties exists between directions (00.2) and (11.0), the difference between residual elastic strains measured for these reflections was plotted, together with the ‘difference strain’ between (00.2) and (10.1). These showed a very good correlation with the plastic strain profile introduced by laser shock peening.

In order to predict the durability of engineering components and improve performance, it is mandatory to understand residual stresses. The last decade has witnessed a significant increase of residual stress evaluation using diffraction of penetrating radiation, such as neutrons or high energy X‐rays. They provide a powerful non‐destructive method for determining the level of residual stresses in engineering components through precise characterisation of interplanar crystal lattice spacing. The unique non‐destructive nature of these measurement techniques is particularly beneficial in the context of engineering design, since it allows the evaluation of a variety of structural and deformational parameters inside real components without material removal, or at worst with minimal interference. However, while most real engineering components have complex shape and are often large in size, leading to measurement and interpretation difficulties, since experimental facilities usually have limited space for mounting the sample, limited sample travel range, limited loading capacity of the sample positioning system, etc. Consequently, samples often have to be sectioned, requiring appropriate corrections on measured data; or facilities must be improved. Our research group has contributed to the development of engineering applications of high‐energy X‐ray diffraction methods for residual stress evaluation, both at synchrotron sources and in the lab setting, including multiple detector setup, large engineering component manipulation and measurement at the UK Synchrotron Radiation Source (SRS Daresbury), and in our lab at Oxford. A nickel base superalloy combustion casing and a large MIG welded Al alloy plate were successfully studied.In order to predict the durability of engineering components and improve performance, it is mandatory to understand residual stresses. The last decade has witnessed a significant increase of residual stress evaluation using diffraction of penetrating radiation, such as neutrons or high energy X‐rays. They provide a powerful non‐destructive method for determining the level of residual stresses in engineering components through precise characterisation of interplanar crystal lattice spacing. The unique non‐destructive nature of these measurement techniques is particularly beneficial in the context of engineering design, since it allows the evaluation of a variety of structural and deformational parameters inside real components without material removal, or at worst with minimal interference. However, while most real engineering components have complex shape and are often large in size, leading to measurement and interpretation difficulties, since experimental facilities usually have limited space for mounti...

Precise channel-to-energy conversion is very important in full-pattern refinement in energy-dispersive X-ray diffraction. Careful examination shows that the channel-to-energy conversion is not entirely linear, which presents an obstacle to obtaining accurate quantitative data for lattice strains by pattern refinement. In order to establish an accurate quadratic channel-to-energy conversion function, a Matlab program was written to find the best quadratic coefficient and hence the whole energy conversion function. Then this energy conversion function was used to perform a whole-pattern fitting of the energy-dispersive X-ray diffraction pattern of a Ti64 sample. The strain across the Ti64 bar calculated from the fitting results has been compared with values obtained by single-wavelength X-ray diffraction utilizing a Laue monochromator. © 2005 International Union of Crystallography.

Friction welding processes, such as friction stir welding (FSW) and inertia friction welding (IFW) are popular candidate procedures for joining engineering materials (including dissimilar pairs) for advanced applications. The advantages of friction welding include lack of large scale material melting, ability to join dissimilar materials, and relatively low propensity to introduce defects into the weld joint. For these reasons FSW and IFW have become the subjects of a number of studies aimed at optimising the joining operations to obtain improved joint strength and reduce distortion and residual stress. In the present study we used the diffraction of high energy polychromatic synchrotron X-rays to measure interplanar lattice spacings and deduce nominal elastic strains in friction stir welds between dissimilar aluminium alloys AA5083 and AA6082, and in coupons from inertia friction welds between dissimilar nickel-base superalloys IN718 and RR1000. Energy-dispersive diffraction profiles were collected by two detectors mounted in the horizontal and vertical diffraction planes, providing information about lattice strains in two nearly perpendicular directions lying almost in the plane of the plate samples mounted perpendicularly to the incident beam. Two-dimensional maps of residual stresses in friction-welded joints were constructed. Apart from the 2D mapping technique, the sin2ψ method (transmission) was also used in the case of inertia friction-welded joint between nickel alloys. Comparison between the two results allowed the variation of the lattice parameter with the distance from the bond line to be deduced. It was found that friction welding of two dissimilar materials with significant strength mismatch may lead to the creation of a region of compressive stress in the vicinity of the bond line, in contrast with the behaviour observed for joints between similar materials.

Foreign object damage (FOD) in gas turbine engines occurs due to the ingestion of small inorganic particles (small stones and sand particles). The damage caused to the blade leading edge may lead to premature crack initiation and ultimately blade failure due the action of time-varying tensile loads. The problem of evaluating the severity of FOD and the induced reduction of component life was investigated in the laboratory, by reproducing the damage conditions accurately and subjecting the impacted blade to fatigue loading simulating the service conditions. One particular aspect of post-FOD analysis focuses on the evaluation of residual stresses in the vicinity of the notch. Residual stresses play an important rôle in controlling the rate of crack initiation and propagation, and may be responsible for accelerated crack growth if they are tensile ahead of the incipient crack, or can cause retardation otherwise. The present study was aimed at experimental and numerical investigate the magnitude and spatial variation of residual stresses in this region. Experimentally, a gas gun was used to introduce the damage by firing a hardened steel cube "point first". Following impact the residual stresses were evaluated using two different experimental techniques involving X-ray diffraction: laboratory low energy monochromatic stress measurement, and high-energy white beam synchrotron stress measurement. The results are compared with the numerical model of the impact phenomenon that was constructed for a selected portion of the blade material, and from which the residual stress pattern following simulated impact was calculated using Bammann damage material model. Both sets of experimental measurements are critically compared with the numerical result, and the relationship between them is discussed. © 2006 Elsevier Ltd. All rights reserved.

Deep Brain Stimulation (DBS) has gained increasing attention as an effective method to mitigate Parkinsons disease (PD) disorders. Existing DBS systems are open-loop such that the system parameters are not adjusted automatically based on patients behavior. Classification of human behavior is an important step in the design of the next generation of DBS systems that are closed-loop. This paper presents a classification approach to recognize such behavioral tasks using the subthalamic nucleus (STN) Local Field Potential (LFP) signals. In our approach, we use the time-frequency representation (spectrogram) of the raw LFP signals recorded from left and right STNs as the feature vectors. Then these features are combined together via Support Vector Machines (SVM) with Multiple Kernel Learning (MKL) formulation. The MKL-based classification method is utilized to classify different tasks: button press, mouth movement, speech, and arm movement. Our experiments show that the lp-norm MKL significantly outperforms single kernel SVM-based classifiers in classifying behavioral tasks of five subjects even using signals acquired with a low sampling rate of 10 Hz. This leads to a lower computational cost., 38th Annual International Conference of the IEEE Engineering in Medicine and Biology Scociety

Residual elastic strains in a bent bar of titanium alloy Ti-6Al-4V were measured using high energy diffraction on station 16.3 at SRS Daresbury. Using a single bounce Laue crystal monochromator, diffraction peaks were collected for reflections (00.2), (10.1), (10.2) and (11.0) from the hcp alpha phase of the titanium alloy. Reference values of the lattice spacing for each of the reflections were found from the diffraction pattern collected from a stress-free sampling volume. The residual elastic strain values calculated on the basis of each reflection were then computed and plotted as a function of position across the bent bar. The average macroscopic residual elastic strain was computed using an averaging procedure taking into account the multiplicity of each reflection. Energy dispersive white beam diffraction from the same bent bar was used to collect diffraction patterns over the range of lattice spacings between 0.8 and 2.2 A. Detector calibration was carried out using the procedure described in Liu et al. (2005) and detailed interpretation of the energy dispersive profiles was carried out allowing the identification of average residual elastic strains in the two principal phases present in the titanium alloy considered, the α-Ti hcp and the β-Ti bcc phases. Peak-specific residual strain profiles computed on the basis of monochromatic measurements show significant differences reflecting the variation in the elastic and plastic properties with grain orientation, i.e., crystal anisotropy. Using the contrast between the elastic and plastic properties of different directions within the α-Ti hcp lattice, the difference between residual elastic strains measured for (00.2) and (11.0) reflections was plotted, as well as the ‘difference strain’ between (00.2) and (10.1) reflections. These profiles show a good qualitative correlation with the plastic strain profile introduced by inelastic bending that was computed from the analysis of Pawley refinement of the energy-dispersive diffraction measurements.

This paper presents the results of a study of elastoplastic deformation of titanium alloy Ti-6Al-4V subjected to four point bending prior to residual elastic strain measurements by high energy synchrotron diffraction. Both white-beam and monochromatic x-rays were used at the SRS Station 16.3 in order to record diffraction patterns as a function of beam position across the sample. This allowed the comparison between the two techniques to be readily made. Residual (elastic) strain was calculated as a function of position across the sample, based on different reflections of hcp titanium. Inelastic bending analysis was used to extract the plastic strains. The results demonstrate that (i) the level of plastic deformation can be deduced from the x-ray diffraction profile, (ii) the asymmetry of the material response to plastic deformation in tension and compression can be identified and (iii) differences in the behaviour of different grain groups can be seen. © 2005 IOP Publishing Ltd.

In children, the ratio of forced expiratory volume in 1 s (FEV₁) to forced vital capacity (FVC) is reportedly constant or falls linearly with age, whereas the ratio of residual volume (RV) to total lung capacity (TLC) remains constant. This seems counter-intuitive given the changes in airway properties, body proportions, thoracic shape and respiratory muscle function that occur during growth. The age dependence of lung volumes, FEV₁/FVC and RV/TLC were studied in children worldwide. Spirometric data were available for 22,412 healthy youths (51.4% male) aged 4-20 yrs from 15 centres, and RV and TLC data for 2,253 youths (56.7% male) from four centres; three sets included sitting height (SH). Data were fitted as a function of age, height and SH. In childhood, FVC outgrows TLC and FEV₁, leading to falls in FEV₁/FVC and RV/TLC; these trends are reversed in adolescence. Taking into account SH materially reduces differences in pulmonary function within and between ethnic groups. The highest FEV₁/FVC ratios occur in those shortest for their age. When interpreting lung function test results, the changing pattern in FEV₁/FVC and RV/TLC should be considered. Prediction equations for children and adolescents should take into account sex, height, age, ethnic group, and, ideally, also SH.

This paper presents the results of synchrotron X-ray diffraction measurement of residual elastic strains in a bent magnesium alloy bar using two different techniques. In the first technique the sample was scanned transversely to a monochromatic X-ray beam. The scattered X-rays were recorded on a phosphoric image plate that was translated at a proportional speed but in the opposite direction to the sample. This enabled the creation of a two-dimensional recording of one-dimensional diffraction patterns. In the second technique a white X-ray beam is used in combination with an energy-discriminating detector mounted at a fixed angle to record similar patterns at each gauge volume position within the sample. The motivation for comparing the results of two measurement techniques is to establish whether the same accuracy in a diffraction strain evaluation can be achieved. It was found that the translating image plate arrangement requires a certain amount of care in calibration and interpretation, but provides a quick and efficient method that can be competitive with the white beam energy-dispersive mode which is known to deliver a fast diffraction capability.

Evaluation of residual elastic strain within the bulk of engineering components or natural objects is a challenging task, since in general it requires mapping a six-component tensor quantity in three dimensions. A further challenge concerns the interpretation of finite resolution data in a way that is commensurate and non-contradictory with respect to continuum deformation models. A practical solution for this problem, if it is ever to be found, must include efficient measurement interpretation and data reduction techniques. In the present note we describe the principle of strain tomography by high energy X-ray diffraction, i.e. of reconstruction of the higher dimensional distribution of strain within an object from reduced dimension measurements; and illustrate the application of this principle to a simple case of reconstruction of an axisymmetric residual strain state induced in a cylindrical sample by quenching. The underlying principle of the analysis method presented in this paper can be readily generalised to more complex situations., 10 pages, 6 figures

Interpretation of pulmonary function tests basically depends on prediction of normal values derived from equations using non-deformed body height. In many patients body height can not be accurately measured. The arm-span method has been used for estimating body height, but the normal relationship between body height and arm span is not exact and differs in various ethnic groups and even between two genders of the same race. In order to minimise the error of estimation of non-deformed body height, the normal relationship between body height and arm span was determined for 754 Persian males and 708 females aged 7 to 82 years, all having normal body stature. In accordance with earlier reports, two sets of spirometric parameters derived once from height, sex, age; and again from arm-span, sex, age were statistically different, and overestimated when the measured arm-span was used. The body-height/arm-span relationship is described using linear regression equations; in subgroups aging 20 years or less and those older than 20 in different genders. The results indicate significant sex and age differences in the arm-span/height ratio. Two sets of spirometric parameters predicted by real height, sex, age/and predicted height, sex, age were not statistically different for most of the parameters especially vital capacity.height estimated from arm span, performs much better than arm span to predict pulmonary function parameters.

In 1947 Kathleen Lonsdale conducted a series of experiments on X-ray diffraction using a divergent beam external to a crystal sample. Unlike the Kossel technique, where divergent X-rays are excited by the presence of fluorescing atoms within the crystal, the use of an external divergent source made it possible to study non-fluorescing crystals. The resulting photographs not only illustrated the complexity of X-ray diffraction from crystals in a truly beautiful way, but also demonstrated unprecedented experimental precision. This long-forgotten work is repeated here using a synchrotron radiation source and, once again, considerable merit is found in Lonsdale's technique. The results of this experiment suggest that, through the use of modern 'third-generation' synchrotron sources, divergent-beam diffraction could soon enjoy a renaissance for high-precision lattice-parameter determination and the study of crystal perfection.

Asthma is the most common chronic disease in children. There are scattered epidemiological data concerning the prevalence of this disorder in developing countries. From October 1998 to May 1999 we studied 4069 randomly selected, junior high-school children in urban areas of Isfahan for asthma and related symptoms. The ages were expected to be 12-15 years. The children completed a questionnaire, and 3924 completed questionnaires were returned (response rate = 96.4%). Pupils with chronic respiratory symptoms were interviewed, physically examined at hospital and 1710 of them also underwent post exercise spirometry. The overall prevalence of asthma ever in life was 9.5%, with a male to female ratio of 2/1. The frequencies of current asthma, wheezing ever in life and exercise induced wheezy breathing were 7.3%, 19.1% and 14.2% respectively. Wheeze was heard on chest auscultation in 4.1% of the children. Pulmonary function tests revealed forced expiratory volume in 1 sec (FEV1)80% in 5.9%, forced mid-expiratory flow (FEF25-75)70%, in 9.7% and FEF7570% in 20.6% of the tested children. All of the later findings strongly correlate with history of asthma. Parental smoking, similar illness in parents and/or siblings, lower levels of parental education and presence of cats, cockroaches and chicken in the household were significant risk factors. The prevalence of asthma in the students of the junior high schools of Isfahan is not far less than the average rates reported in many parts of the world, and it seems necessary to pay more attention to poorly controlled air pollution in Isfahan as an industrial city.

As developing countries adopt an industrialized style of living, an increase in asthma prevalence can be expected. A cross sectional study was undertaken to evaluate the prevalence rates of asthma and related symptoms and clinical findings in Isfahan, Iran. A randomly selected population of Isfahan primary school children, consisting of 3,982 children aged 6 to 11 was enrolled in the study. Parents completed a Persian questionnaire modified from ISAAC and ECRHS questionnaires. The returned 3,828 (96.1%) questionnaires were reviewed and 686 children suffering from asthma or any of the related symptoms were invited for further evaluations. In this stage 655 children (95.5%) underwent a medical interview and physical examinations, of which 415, underwent post exercise spirometry and body-plethysmography. The prevalence rates for previously diagnosed asthma, dyspnea and wheezing ever, dyspnea and wheezing in the last 12 months and frequently recurring dyspneal attacks were 0.71%, 7.6%, 3.9% and 1.6%, respectively. Wheezing was heard upon auscultation of the chests of 70 children (10.7%). Forced expiratory volume in 1st second (FEV1)80% of prediction was recorded in 3.1% of the children, other findings included reduced peak expiratory flow rate (PEF), mean expiratory flow 25 to 75 percent (FEF 25-75), forced expiratory flow at 75% of FVC (FEF 75), and increased residual volume (RV) and air-ways resistance in 4.3%, 10.6%, 21.2%, 30.1% and 63.2% of the pupils, respectively. We conclude that asthma screening programs employing clinical methods should be encouraged, but measurement of airway resistance is not a suitable tool for epidemiologic studies.