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A thorough understanding of droplet impact and freezing is vital in preventing ice accretion on many outdoor devices. This simulation-based study investigated the effect of surface morphology on the impacting-freezing process of a supercooled droplet. Also, the variations of Weber number and supercooling temperature were studied numerically. The droplet impact and freezing process were simulated with the volume of fluid method and freezing model. A more accurate simulation was achieved by modeling the supercooled droplet and the dynamic contact angle. At the given ranges of the input parameters, the main factors that guaranteed droplet rebounding after collision were determined. The supercooling temperature and the groove width should be above 266 K and less than 0.21 mm, respectively. The droplet should also maintain its cohesion and integrity during impact. Creating grooves on a surface is novel and paves a new way to understand the impact and solidification of water droplets in supercooled conditions. [ABSTRACT FROM AUTHOR]

This study aims to determine patterns of isotope discrimination between diet and blood and feathers in the common coot (Fulica atra) in Lake Tonga, North-eastern Algeria, the first time in Algeria on the aquatic avifauna. For this purpose, we investigate the trophic position of the species looking for the seasonal variations in the diet. The stable isotope analysis of nitrogen and carbon was carried out to provide a comprehensive evaluation of the feeding ecology. After plotting the isotopic composition of all potential food sources in the mixing plot, consumed by the coat, whether it is on feathers or blood, the results revealed that the main source of the coot diet in all seasons is Najas pectinata, followed by Gambusia affinis. Whereas, for Nymphaea alba a stable contribution was recorded during both seasons (breeding and reproduction). The food selection of a species is predetermined by its ability to exploit its trophic space, on one hand, and specific nutritional requirements are also essential to various biological functions of the species concerned. [ABSTRACT FROM AUTHOR]

In this study, a 2600-ha Ramsar site, Lac Tonga, in northeastern Algeria, was fortnightly surveillance, for seven months, from December 2021 to June 2022. The aim was to monitor and determine the spatio-temporal distribution of Ardeidae. A total of seven species were inventoried, including the Western Cattle egret Ardea ibis (1701 individuals) and the Little egret Egretta garzetta (265 individuals). The other species were the Squacco heron Ardeola ralloides, Grey heron Ardea cinerea, Purple heron Ardea purpurea, Black-crowned Night heron Nycticorax nycticorax and Great egret Ardea alba, with 69, 56, 54, 51 and 35 individuals respectively. During the study period, maximum abundance was observed during May (A=582 individuals), and species richness generally varied between 3 and 5 species. The highest diversity and equitability indices values were noted during June (H'=1.4 bits and E=0.88), indicating the presence of a balanced population. The monitoring of Ardeidae’ spatial distribution shows that they exploit mainly the western and northeastern parts of the lake with an important occupation during the study period. [ABSTRACT FROM AUTHOR]

STUDY QUESTION In a non-commercial national gamete donation programme, do the motivations and personality characteristics of candidate sperm and oocyte donors differ according to their parenthood status? SUMMARY ANSWER Moderate differences exist between non-parent and parent candidate donors in motivations for gamete donation and representations as well as in personality characteristics. WHAT IS KNOWN ALREADY Several studies have analysed the motivations and experiences of oocyte or sperm donors, but mainly in countries where gamete donation is a commercial transaction, and very few studies have reported results of personality traits using personality inventory tests. No study has specifically investigated the motivations and personality characteristics of candidate gamete donors according to parenthood status. STUDY DESIGN, SIZE, DURATION A prospective study was carried out including 1021 candidate donors from 21 centres (in university hospitals) of the national sperm and egg banking network in France between November 2016 and December 2018. PARTICIPANTS/MATERIALS, SETTING, METHODS In total, 1021 candidate gamete donors were included in the study. During their first visit, male (n = 488) and female candidate donors (n = 533) completed a questionnaire on sociodemographic characteristics, their motivations for donation and their representations of donation, infertility and family. Secondly, a NEO Personality Inventory (NEO-PI-R) exploring the Big Five personality traits was completed online. Results were compared between parent and non-parent candidate donors. MAIN RESULTS AND THE ROLE OF CHANCE Altruistic values were the principal motive for donation irrespective of parenthood status. Reassurance about their fertility or preservation of sperm for future use was more often reported in non-parent than in parent candidate donors. With regard to representation of gamete donation or of the family, independently of their parenthood status, candidate donors more frequently selected social rather than biological representations. Mean personality characteristics were in the normal range. Non-parent candidate donors had higher scores on openness and depression than parents, while parent candidate donors appeared more social than non-parents. LIMITATIONS, REASONS FOR CAUTION The personality characteristics inventory was not completed by all candidate donors included in the study. However, family status did not differ between the two groups (NEO-PI-R completed (n = 525) or not), while the group who completed the NEO-PI-R had a higher educational level. This national study was performed in a country where gamete donation is subject to strict legislation. WIDER IMPLICATIONS OF THE FINDINGS In a global context where reproductive medicine is commercialized and gamete donor resources are limited, this study found that altruism and social representations of gamete donation and family are the main motivations for gamete donation in a country which prohibits financial incentive. These findings are relevant for health policy and for gamete donation information campaigns. STUDY FUNDING/COMPETING INTEREST(S) Grant from the Agence de la Biomédecine, France. The authors have nothing to disclose related to this study. TRIAL REGISTRATION NUMBER N/A. [ABSTRACT FROM AUTHOR]

In this study, the effects of a commercial coating and its combination with aluminum and copper microparticles were investigated on condensation heat transfer. Thus, the impacts of different coating thicknesses and different weight percentages of microparticles in coatings on the heat transfer coefficient, heat flux, contact angle, and contact angle hysteresis were investigated. The heat transfer coefficient and heat flux values of the plate with Danphobix coating that was mixed with hydrophilic aluminum microparticles with the weight percentage of 3% and coating thickness of 17 µm was increased by 2.22–2.8 times and 2.2–2.52 times, respectively, compared to the no-coating plate. [ABSTRACT FROM AUTHOR]

This study concerns the effect of bicrystal spatial orientation on the iron Σ5 boundary under nanoindentation tests. The orientation of the bicrystal is changed relative to the indenter by the parameter "nanoindentation angle" to create dislocation collisions with grain boundary in different directions and to determine the possibility of transmission of these dislocations through the grain boundary. Simulations were carried out for nanoindentation angles between −90° and 90° with a resolution of 18°. Molecular dynamics with EAM atomic potential functions are employed for the simulations. The effect of nanoindentation angle on the crystals Young's modulus, shear stress, hardness, and Poisson's ratio were determined. Due to the periodicity which has been observed in all of the aforementioned quantities of the rotated crystal, analytical equations were extracted by adapting the Fourier series expansion on the calculated data. Some explanations were provided for the dislocation behaviors based on the physics of the problem and also by the results reported in the literature. Simultaneous effects of Poisson's ratio and pile-ups on each other were also investigated and interpreted. [ABSTRACT FROM AUTHOR]

Ni1−x(Zn0.6Mg0.2Cu0.2)xFe2O4 (where x = 0.0, 0.3, 0.5 and 0.7) was prepared by the auto combustion method and was characterized by X-ray diffraction (XRD). From XRD analysis, the average crystallite size and lattice constant were determined in the range of 6–11 nm and 8.331–8.372 Å, respectively. The structure of single-phase cubic in samples was also confirmed because the main peaks of the patterns were related to the position of the peaks in the mentioned standard (JCPDS card no. 00-008-0234). The average size of the particle was calculated in the range of 21–26 nm from the field emission scanning electron microscopy (FESEM). The atomic percentage of elements was obtained from the energy dispersive spectroscopy (EDS). From room-temperature hysteresis loops, the magnetization was evaluated in a magnetic field of 9 kOe. It was observed that the magnetization was not saturated and was increased with the increment in x values. According to the core–shell model, the magnetic behaviour of samples were discussed. The results illustrated that the magnetization of the sample with x = 0.7, due to the larger particle size than that of other samples, was the highest. In addition, the increase in magnetization was also discussed based on Neel's theory and the site's occupation of the substituted cations on the sub-lattices. Also, the variation of coercivity was investigated. The coercivity, due to the multi-domain structure of samples, was decreased with doping Zn, Mg and Cu. Among all the samples, the sample with x = 0.7 indicated the lowest coercivity and the sample with x = 0 showed the highest coercivity. Based on the domain wall movement, the variations of initial permeability as a function of frequency in the frequency range of 10 kHz–10 MHz were discussed. The results indicated that the initial permeability of the sample with x = 0.7, similar to its magnetization, was the highest. The constancy of µ′ in the frequency range of 10 kHz–1 MHz was due to the motion of the domain wall, which was indicated by the compositional stability and quality of the samples. Finally, the results obtained from the initial permeability in the present work were compared to the values obtained from the previous researchers. Generally, it was observed that the sample with x = 0.7, due to the maximum magnetization, highest initial permeability and lowest coercivity could be suitable for high-frequency applications. [ABSTRACT FROM AUTHOR]

Imatinib introduction caused to improve the clinical outcomes of chronic myeloid leukemia (CML) patients. Despite the significant effects of Imatinib, pharmacogenetic variables induced treatment resistant is also observed. Imatinib is known as a Pglycoprotein (P-gp) efflux pump substrate encoded by the ABCB1 gene. The ABCB1 C1236T, G2677T/A and C3435T variants are possibly correlated with interindividual variation in pharmacokinetic response to Imatinib therapy. The present study aimed to examine the effect of ABCB1 gene variants on the therapeutic response of Imatinib in CML patients. Sixty-nine Iranian CML patients treated with Imatinib or Nilotinib were selected and divided into two groups of sensitive and resistant to Imatinib. C1236T and G2677T/A variants were genotyped by high resolution melting (HRM) analysis, and C3435T variant was genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Then, the results were compared between the two groups of patients. Our results showed that there were no significant differences between C1236T, G2677T/A and C3435T variants of ABCB1 gene and clinical response to Imatinib in the Iranian CML patients. According to the results of this study, genotyping of ABCB1 C1236T, G2677T/A and C3435T variants couldn't help to predict the outcomes of Imatinib treatment in CML patients. So, these variants are not useful to make decisions about treatment, but it is suggested to do further investigations. [ABSTRACT FROM AUTHOR]

In this research is presented a method for technological capabilities assessment in a company in transformer industry. Used and discussed criteria in this technique are merely developed to assess technological capabilities in transformer industry. Based on literature, technological capabilities in transformer industry are divided into three main categories: production capability, development and investment capability, and innovation capability. For assessing each of the above mentioned using four technology components as an entry and indicators of different technological capabilities assessment models, and for quantifying different components, it is required to use Atlas technology model. It is required to mention that indicators relating to transformer production industry have been recognized and technological capabilities status has been determined. Finally, it could be concluded that how the level of this company is in terms of production capability, development, and innovation capability. From the conducted studies in the case, some technological capabilities indicators, effective factors in technological capabilities enhancement are drawn and procedures to increase technological capabilities are presented. Finally, problems and obstacles are identified. [ABSTRACT FROM AUTHOR]

Presents information on a study which examined the excitons in undoped InGaAs pseudomorphic quantum wells with gallium arsenide and AlGaAs barrier layers using photoluminescence and photoluminescence excitation spectroscopy. Difference between samples of quantum wells; Temperature dependence of the samples; Conclusions.

The effects of the camber ratio on the hydrodynamic and structural behaviors of a NACA-based ducted marine propeller in the wake flow behind an underwater axisymmetric body are numerically studied by computational fluid dynamics methods, in particular, the finite element method. The results are presented in terms of the efficiency, deflection, pressure coefficient, and natural frequencies. It is shown that the wake flow strongly affects the performance of the selected propulsion system. It is shown that the distributions of the camber ratio over the blades of the propeller nonlinearly changes its resistance against cavitation occurrence and deflection, and also changes its hydrodynamic performance and vibrational behavior. [ABSTRACT FROM AUTHOR]

The present paper numerically discusses the design procedure of marine ducts used for multi-component ducted propulsion systems at the stern of an axisymmetric submerged body. The results are presented in the form of tables showing the effects of dihedral angel as well as camber ratio of the duct as the two most important geometrical parameters on hydrodynamic performance of the propulsion system. Furthermore, a correlation has been extracted between the results of two and three dimensional analysis of ducted propellers. The results show that the design procedure of the duct used for a ducted propulsion system could be performed using some two dimensional analyses. The simulations are performed using a Reynolds averaged Navier Stokes Equations (RANS) based Computational Fluid Dynamics (CFD) tool. [ABSTRACT FROM AUTHOR]

Deals with a study which investigated AlGaAs/GaAs double-heterojunction high electron mobility transistors (DHHEMT), which were grown by low-pressure organometallic vapor phase epitaxy. Use of the magnetic filed-dependent Hall effect measurement; Comparison of the DHHEMT with the conventional single-heterojunction high electron mobility transistors; Requirements for growing the multilayer device structures.

The role of autonomous underwater vehicles (AUVs) is more important in the quest to reach the deep seas today than ever before. The hull shape of the AUV can differ depending on the special mission considered for the vehicle. Therefore, different types of algorithms for the body shape design of these kinds of vehicles are being developed every day. In the current work, a new procedure has been proposed for designing the body shape of an AUV. Using this method which is based on a desired pressure distribution, it is possible to obtain the desired hull shape design. Artificial neural network algorithm has been used for this purpose. Preliminary data for training and testing of the network have been obtained from CFD simulation of the flow around the body of Hydrolab500 AUV. In this regard, pressure distribution has been evaluated around each body by changing the nose and tail profile of AUV. The results obtained from this research indicate that a body correlated to the desired pressure can be designed properly. [ABSTRACT FROM AUTHOR]

Hydrodynamic coefficients or hydrodynamic derivatives of autonomous underwater vehicles (AUVs) play an important role in their development and maneuverability. The most popular way of estimating their coefficients is to implement captive model tests such as straight line tests and planar motion mechanism (PMM) tests in the towing tanks. This paper aims to develop an apparatus based on planar experiments of water tunnel in order to estimate hydrodynamic derivatives due to AUVs' acceleration and velocity. The capability of implementing straight line tests and PMM ones using mechanical oscillators located in the downstream flow of the model is considered in the design procedure of the system. The hydrodynamic derivatives that resulted from the acceleration and velocity of the AUV model were estimated using the apparatus that we developed. Static and dynamics test results were compared for the similar derivatives. The findings showed that the system provided the basis for conducting static tests, i.e., straight-line and dynamic tests that included pure pitch and pure heave. By conducting such tests in a water tunnel, we were able to eliminate errors related to the time limitation of the tests and the effects of surface waves in the towing tank on AUVs with applications in the deep sea. [ABSTRACT FROM AUTHOR]

According to previous studies the IRF6rs2235371 polymorphism is a risk factor for NSCL/P in different populations. However our recent study revealed no correlation between IRF6rs642961 and NSCL/P in our population. In the present study we have investigated the relationship between IRF6rs2235371 and NSCL/P in same group to determine whether IRF6rs2235371 is a risk factor in our population as well. We analyzed the IRF6rs2235371 genotype in a subset of the Iranian population using the Polymerase Chain Reaction technique. The PCR products were digested with DpnII. Chi-square test was applied to analyze the obtained result. The patients were supplied by the Cleft Lip and Palate Clinic of the Isfahan University of Medical Science. A clinician ascertained the non-syndromic status of all patients and that no clefting drugs, ethanol or smoking were abused during pregnancy. The control group was selected from unaffected subjects with no history of NSCL/P in their families. 107 patients from 107 Iranian unrelated families and 100 controls were screened. There was a significant association between the IRF6rs2235371 genotype sand an increased NSCL/P risk. Our data indicates that the IRF6rs2235371 variation can increase the risk of NSCL/P in the Iranian population. This result is in contrast with the results of our recent study on the correlation between the IRF6rs642961 polymorphism and NSCL/P in the same group. [ABSTRACT FROM AUTHOR]

Optical properties of transition metal dichalcogenides monolayer of MoS2 are analyzed using multi-orbital tight-binding models with only Mo d-orbitals (three-band model) and with an inclusion of S p-orbitals (six-band model). We look at band structures, momentum matrix elements between valence and conduction band, and joint optical density of states. Good agreement between the two models is shown in a vicinity of K point of the Brillouin zone. On line connecting K and Gp points, a local conduction band minimum at Q point is recovered only by six-band model in agreement with density functional theory and experimental results. We show that optical transitions at this point are active for both light polarizations. A peak in joint optical density of states is also seen at this point suggesting its potentially important role in a proper description of excitonic effects. [ABSTRACT FROM AUTHOR]

The present work examines the role of chaotic mixing as a means of heat transfer enhancement in plate heat exchangers. In order to demonstrate the chaotic behavior, sensitivity to initial conditions and horseshoe maps are visualized. The Nusselt number and the friction factor were computed in the range of reynolds number, 1 < Re < 10. The Nusselt number increases considerably in chaotic models whereas the friction factor increases only marginally. [ABSTRACT FROM AUTHOR]

In this paper, an approach is identified using concepts in molecular dynamics (MD) and discrete element method (DEM) to generate the microstructure of polycrystalline materials. Using the proposed methods, different types of particles with different grain size and volume fraction in the real material, can be easily generated. It is assumed that the particles can be randomly packed together into a simulation region, by defining artificial interaction forces among them. Such forces may be either adopted from Van der Waals potential energy, or Hooke pair and gravity forces. The proposed method has proved to be fast due to the fact that the algorithm has been implemented on graphical processing units (GPU). Utilizing the Voronoi tessellation method, the set of the generated discrete grains have been altered to space-filling, adjoining polyhedrons with respect to the real geometry. Moreover, as an advantage, the boundary and the interface region of the microstructures were modeled. [ABSTRACT FROM AUTHOR]

Background Thalassemia intermedia is a variety of beta thalassemia which shows clinical symptoms somewhere between asymptomatic carriers and thalassemia major. Cardiac dysfunctions due to chronic anemia and hemosiderosis are the major causes of death in these patients. The purpose of this study is to evaluate cardiac function in these patients by echocardiography. Materials and Methods This case-control study was conducted on 22 thalassemic patients (mean: 16.5±5.8 years) and 66 healthy individuals (mean:16.07± 2.9years) as a control group from January 2007 to July 2008. There was no sign of cardiac involvement by physical examination, chest x-ray and ECG in patients. Echocardiographic parameters were measured in groups, and finally data was analyzed by SPSS software. Results The mean of left ventricular myocardial performance index (MPI) (P-value=0.0001) and left ventricular mass index (LVMI) (P-value=0.0001) have statistically significant difference. Mean of interventricular septal dimension in diastole (IVSD), left ventricular posterior wall thickness in diastole (LVPWD), interventricular septal dimension in systole (IVSS) and left ventricular posterior wall dimension in systole (LVPWS) were also statistically significant with a P-value of, 0.002, 0.001, 0.01, 0.003, respectively. Aortic Pre-ejection period/Ejection time (PEP/ET) (P-value=0.009), ejection fraction (EF) (P-value=0.019), fractional shortening (SF) (P-value=0.041), left ventricular isovolumetric contraction time (ICT) (Pvalue= 0.0001) and left ventricular isovolumetric relaxation time (IRT) (P-value=0.0001) were statistically significant. Mean of right ventricular MPI (P-value=0.0001) and IRT (P-value=0.0001) were also significantly different between two groups. Others echocardiographic parameters were not statistically significant (P-value>0.05). Conclusion Heart failures are earlier affected thalassemia intermedia patients compared with control group. [ABSTRACT FROM AUTHOR]

This study presents energy efficiency measures in fans as an important energy consumption facility in the industry and common usages by identifying the sources of energy loss and applying methods to reduce those losses, which are one of the critical issues in protecting the environment and in global warming. The carbon footprint can be lowered by reducing the energy consumption of a fan over its life cycle. The main sources of energy loss in fans such as noise, vibration, lubrication, temperature of the bearings, installation type, damper and filter, especially pulley and belt system compared to electrical variable speed drive, are theoretically and experimentally discussed. The laboratory results show that the mechanical variable speed drive is one of the critical sources of energy loss in centrifugal fans. The results also show that by changing the drive with an electrical variable speed drive, the energy usage can be substantially optimized. For instance, using an electrical variable speed drive has reduced the energy loss up to 38.5 % with regard to the speed and according to the different flow rates. Moreover, based on the results derived from the equations and figures, it can be concluded that a considerable amount of energy per year, as well as the related cost can be saved and this shall be noted particularly in industrial applications. [ABSTRACT FROM AUTHOR]

The dynamics of an electrical-driven linear nanopump, consisting of a carbon nanotube, a C60+ molecule and a graphene sheet, has been simulated via the application of the molecular dynamics method. In this nanopump, the nanotube and the graphene sheet are used as the sleeve of the pump and the boundary between the two sides of the nanopump, respectively. By exposing the nanopump to an external alternative electric field, the C60+ molecule will be oscillating linearly in the nanotube. We found that the linear oscillating motion of the C60+ molecule causes the gas atoms to flow through the nanotube, and a density gradient is generated between the two sides of the nanopump. Also, it was observed that the frequency of the external alternative electric field affected the pump performance in the generation of the density gradient amount. The maximum performance occurred at a specific frequency of the electric field. This specific frequency can be computed by an analytical formula for given materials and temperatures. Moreover, the results indicate that the length of the nanotube can affect the gas pumping. [ABSTRACT FROM PUBLISHER]

In this study, environmental impacts of industrial waste disposal of used lubricating oils and sulphur wastes scenarios have been investigated and modeled. The life-cycle assessment methodology was selected among the environmental impact assessment methods. In this method environmental issues and burdens were quantitated in order to facilitate the comparison. In this regard, options with the least adverse impacts were suggested. Functional unit of the study has also been defined as amount of used lubricating oils and sulphur wastes in terms of kilograms based on capacity of transitional barrel. Accordingly, the system boundaries were selected for life cycle of the wastes produced in sulphur unit of Tehran Oil Refinery. Since the main disposal method applied in Tehran Oil Refinery was transference to the municipal landfill, two incineration and landfilling scenarios were modeled for used lubricating oils and sulphur wastes by means of Simapro-7.1 software. Then, the outputs of these scenarios were compared in terms of the least environmental impacts by EDIP 2003 and Ecoindicator 99 methods. Finally, incineration scenarios were recommended as the most efficient ones. [ABSTRACT FROM AUTHOR]

Introduction: This study scrutinized the relationship between attachment styles and love attitudes with the marital values. Method: The sample included 313 single undergraduate students of large universities in Tehran who were chosen by nonrandom sampling at hand. Experimental data were collected using the Adult Attachment Styles Questionnaire, the Love Attitude Scale, and the Adult Marital Values Questionnaire. Results: The statistical analysis indicated that it is possible to predict marital values using attachment style and the kind of love. A negative relationship was found between the Agape love style and hierarchy marital values, and between Agape love style and cognitive autonomy marital values. Storge and Mania love styles had a positive meaningful relationship with Egalitarianism marital values, and the Mania love style, and secure attachment style were positively related to affective autonomy marital values. A negative relationship was observed between Agape love and cognitive autonomy values. In addition, a positive relationship was observed between the Pragma and Agape loving styles and secure attachment with embeddedness. The mania and Pragma love styles were positively related to the general attitude toward marriage. Conclusion: The results show the importance of analyzing attachment style and love attitudes in couples before marriage and how these variables work on marital values. [ABSTRACT FROM AUTHOR]

In this study, adsorption of copper and chromium was investigated by residue of brewed tea (Tea Waste) from aqueous solutions at various values of pH. It was shown that adsorbent dose, copper and chromium ion concentrations in such solutions influence the degree of these heavy metal ions' obviation. The adsorption level of the prepared solutions was measured by visible spectrophotometer. The tea residue adsorbed copper (II) and chromium (VI) ions at initial solution pH by 25 % and 3 %, respectively. During the experiments the peak adsorption occured in hydrated copper nitrate aqueous solution at pH range of 5-6. Likewise the maximum adsorption appeared in potassium chromate aqueous solution at pH range of 2-3. In addition, tea residue adsorbed about 60 mg/g of copper (II) ion at pH=5, while chromium adsorption was registered at about 19 mg/g at pH=2. The data obtained at the equilibrium state, was compared with Langmuir and Freundlich models. Results showed that regarding the kinetics of adsorption, the uptake of copper (II) and chromium (VI) ions by tea residue was comparatively faster, with the adsorption process exhaustion completed within the first 20 min of the experiments. Furthermore, results revealed that adsorption data concerning the kinetic phase is closely correlated with a pseudo-second order model with R² > 0.99 for copper (II) and chromium (VI) ions. [ABSTRACT FROM AUTHOR]

This article presents a numerical investigation of axisymmetric supercavitating flow. It is assumed that such a flow field could be estimated by a potential flow that neglects the viscosity effects and rotational motion of the fluid and assumes the flow as an irrotational flow field. One of the most adequate methods for modelling potential fields is the boundary element method, which is employed in this article. A novel iterative scheme is used to capture the free surface of an axisymmetric supercavity. This numerical algorithm is based on updating an initial guess for the cavity's boundary; the convergence criterion is the pressure amount on the free surface of the cavity, which converges to a constant value. To obtain finite lengths for supercavities, a cavity closure model is applied. The results are in good agreement with similar analytical and numerical solutions as well as the existing experimental data for supercavities characteristic properties and the drag coefficient on cavitators. The present iterative numerical algorithm is reliable for predicting the characteristics of a supercavitating flow. Moreover, the feasibility of the cavity capturing in a flow field with low cavitation number is especially attractive. [ABSTRACT FROM AUTHOR]

The non-invasive assessment of primary achalasia is not precise. To compare investigations before and 1 month after balloon dilation in achalasia. Fifty-two patients with primary achalasia were enrolled. Subjective and objective variables of oesophageal functions were analysed before and 1 month after balloon dilation. The mean predilation symptom score, lower oesophageal sphincter pressure, height and volume of barium at 5 min were 7.7 ± 2.6, 62.0 ± 25.1 mmHg, 9.2 ± 6.1 cm and 53.2 ± 49.8 mL respectively; the mean postdilation values were 3.0 ± 3.0, 34.1 ± 12.5 mmHg, 7.9 ± 5.1 cm and 28.0 ± 30.1 mL respectively. The before dilation volume of barium at 5 min correlates significantly with lower oesophageal sphincter pressure ( P < 0.01). The mean symptom scores, lower oesophageal sphincter pressure and volume of barium at 5 min dropped significantly after intervention ( P < 0.01), but the reduction in barium height at 5 min was not significant. The percentage changes in volume at 5 min significantly predicted the percentage changes in lower oesophageal sphincter pressure ( P < 0.01). The volume of barium retention at 5 min can predict the lower oesophageal sphincter pressure before and after balloon dilation in primary achalasia. This could be used as a non-invasive objective tool for initial and post-dilation assessment. [ABSTRACT FROM AUTHOR]

Several studies have suggested a role for the histocompatibility complex of loci (HLA) in the genetic susceptibility to autism. We have tested this hypothesis by linkage analysis using genetic marker loci in the HLA region on chromosome 6p in multiplex families with autism. We have examined sharing of alleles identical by descent in 97 affected sib pairs from 90 families. Results demonstrate no deviation from the null expectation of 50% sharing of alleles in this region; in fact, for most marker loci, the observed sharing was less than 50%. Thus, it is unlikely that loci in this region contribute to the genetic etiology of autism to any significant extent in our families. [ABSTRACT FROM AUTHOR]

A unique multi-wafer OMVPE reactor with capability to produce atomic-layer abrupt-ness is demonstrated. Uniform GaAs and AlGaAs epitaxial layers were grown on four two-inch wafers or one three- or four-inch wafer. Thickness variation across a three-inch wafer was less than ±2%, while the variation of Al solid composition was less than ±1%. Multiple AlGaAs/GaAs quantum wells ranging in size from 10Å to 140Å were grown with heterointerface roughness less than one monolayer. The electrical properties of HEMT device were studied. Variations of sheet carrier concentration and electron mobility were ±6% and ±5% respectively across a three-inch wafer. The carrier con-centration profile, mobility spectrum and device characteristics of DH-HEMT are also presented. These results indicate that this OMVPE reactor can grow good device struc-tures for microwave and millimeter-wave power device applications. [ABSTRACT FROM AUTHOR]

The deafness mouse has profound sensorineural hearing loss with degeneration of hair cells soon after birth. The mode of inheritance is recessive, and there are no associated phenotypic anomalies. Thus, this mouse provides a model for recessive, nonsyndromic, prelingual deafness. We have mapped the gene causing deafness in the mouse to Chromosome (Chr) 19 by analysis of 230 intersubspecific backcross progeny. No recombinants were found with the microsatellite marker D19Mit14. The loci for two guanine nucleotide-binding proteins are tightly linked to this marker, and they are being investigated as possible candidate genes. The identification of the defective gene in the mouse will help to explain the mechanism that causes hair cell degeneration and is likely to identify a homologous gene for deafness in humans. [ABSTRACT FROM AUTHOR]

GaAs/AlGaAs light-emitting diodes (LED’s) with nipi active regions have been successfully fabricated using sequential n and p diffusions to selectively contact the doping superlattice. By doing sequential patterned sulfur and zinc diffusions, a lateral injection LED can be readily fabricated. Excellent current-voltage characteristics were achieved with reverse breakdown voltages in excess of 9.5 V, indicating that the selective contacts were nearly optimum. cw outputs of 500 μW at 50 mA drive current have been observed. The LED output spectrum was seen to tune with applied bias at a rate of about 650 meV/V at low temperatures. [ABSTRACT FROM AUTHOR]

AlGaAs doping superlattices (‘‘nipi structures’’) have been successfully grown in 30% AlGaAs by molecular beam epitaxy. Tunable photoluminescence (PL) as a function of incident laser intensity has been observed in samples with a wide range of intrinsic layer thicknesses over a temperature range from 2 to 120 K. Luminescence shifts as large as 230 meV were observed for a range of incident intensities of about 500. Low-temperature PL spectra showed a weaker dependence of the peak energy on incident intensity for thicker spacer layers. This decrease in tuning rate can be associated with the reduced probability for tunneling transitions with increasing spacer thickness. [ABSTRACT FROM AUTHOR]

In a closed water-tunnel circuit, the multi-component strain gauge force and moment sensor (also known as balance) are generally used to measure hydrodynamic forces and moments acting on scaled models. These balances are periodically calibrated by static loading. Their performance and accuracy depend significantly on the rig and the method of calibration. In this research, a new calibration rig was designed and constructed to calibrate multi-component internal strain gauge balances. The calibration rig has six degrees of freedom and six different component-loading structures that can be applied separately and synchronously. The system was designed based on the applicability of formal experimental design techniques, using gravity for balance loading and balance positioning and alignment relative to gravity. To evaluate the calibration rig, a six-component internal balance developed by Iran University of Science and Technology was calibrated using response surface methodology. According to the results, calibration rig met all design criteria. This rig provides the means by which various methods of formal experimental design techniques can be implemented. The simplicity of the rig saves time and money in the design of experiments and in balance calibration while simultaneously increasing the accuracy of these activities. [ABSTRACT FROM AUTHOR]