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Purpose: Tumoral calcinosis is a rare clinicopathological entity characterized by ectopic soft-tissue calcification, typically periarticular. Normophosphatemic tumoral calcinosis is seldom reported in East Asian populations, and the preoperative diagnosis is often elusive. This study was performed to characterize the clinical profile of normophosphatemic tumoral calcinosis and investigate the presence of the SAMD9gene mutation. Methods: The clinical features, pathological examination findings, and outcomes of 19 subjects were retrospectively reviewed. All patients were analyzed for SAMD9gene mutation using paraffin-embedded tumoral calcinosis specimens. Results: Nineteen subjects were analyzed (7 males, 12 females). Their mean age at surgery, mean age at symptom onset, and median disease duration was 51.9 ± 17.3 (range 7–75) years, 49.1 ± 17.2 (range 7–74) years, and 1.3 (interquartile range 0.5–3.0) years, respectively. Lesions were located in the hand in 8 (42.1%) subjects; wrist in 5 (26.3%); shoulder in 2 (10.5%); and hip, knee, buttock, and scrotum in 1 (5.3%) subject each. The lesions in 17 (89.5%) subjects were located around the joints [small joints (hand and wrist) in 13 (68.4%) and large joints (shoulder, hip, and knee) in 4 (21.1%)]. Lesions occurred in the upper limbs in 15 (78.9%) subjects and in the lower limbs in 2 (10.5%). Multiple-lesion involvement (distal right index finger and middle finger) occurred in one (5.3%) subject. Symptoms included pain in 15 (78.9%) subjects, impaired mobility in 5 (26.3%), swelling in 5 (26.3%), numbness in 2 (10.5%), and an asymptomatic mass in 2 (10.5%). The serum inorganic phosphorus concentration was normal in all 19 subjects (mean 1.17 ± 0.15 mmol/L). The serum calcium concentration was normal in 18 subjects and low in 1. The serum alkaline phosphatase concentration was normal in all 19 subjects. Pathological examination indicated multiple nodules of calcified materials that manifested an amorphous or granular blue-purple crystal and were surrounded by proliferation of mononuclear or multinuclear macrophages, osteoclastic-like giant cells, fibroblasts, and chronic inflammatory cells. Notably, different phases of pathological manifestations were observed in the same microscopic field. During follow-up (0.5–65.0 months), no recurrence of tumoral calcinosis was observed in 18 (94.7%) subjects, but 1 subject developed in situ recurrence of an asymptomatic subcutaneous mass after 6 months postoperatively. Genetic analysis in all 19 subjects revealed no SAMD9gene mutations. Conclusions: Most subjects were females and developed calcinosis in adulthood. Small joints (hand and wrist) and the upper limbs were frequently involved. The presence of different phases of pathological features in the same subject suggests that about half of the study participants had been misdiagnosed with another condition (such as gout, osteoarthritis, etc.). Complete surgical excision led to cure without recurrence during follow-up in majority of the study participants.

In this study, polydimethylsiloxane and graphene were used to fabricate surface electrodes for electrocardiographic (ECG) sensing. A simple and inexpensive method was developed to fabricate graphene-based polymer films. In this method, graphene was inlaid in polydimethylsiloxane by polymer infiltration. The polymer films were successfully used in ECG measurements and performed as well as conventional silver/silver chloride wet electrodes. Few motion artifacts were observed with the graphene films when body postures were changed and during walking. The presented approach is low-cost and suitable for mass production, holding great promise in fabricating polymer electrodes for medical monitoring.

We theoretically study the formation of the steady state multiple dark photovoltaic solitons in the closed-circuit photovoltaic photorefractive crystal. The results indicate that the formation of the multiple dark photovoltaic solitons in the closed-circuit photovoltaic crystal is dependent on the initial width of the dark notch at the entrance face of the crystal. The number of the solitons generated increases with the initial width of the dark notch. If the initial width of the dark notch is small, only a fundamental soliton or Y-junction soliton pair is generated. As the initial width of the dark notch is increased, the dark notch tends to split into an odd (or even) number of multiple dark photovoltaic solitons sequence, which realizes a progressive transition from a lower-order soliton to a higher-order solitons sequence. When the multiple solitons are generated, the separations between adjacent dark solitons become slightly smaller. The soliton pairs far away from the center have bigger width and less visibility and they move away from each other as they propagate in the photorefractive nonlinear crystal.

This study investigated the clinicopathological characteristics of mucinous gastric carcinoma (MGC) and assessed whether multidetector-row computed tomography (MDCT) could differentiate MGC from non-mucinous gastric carcinoma (NGC). Clinicopathological data from 542 patients with gastric carcinoma (23 MGC, 519 NGC), who underwent pre-operative MDCT examination and curative or palliative gastrectomy, were analysed. Only seven of the 23 patients with MGC were correctly diagnosed pre-operatively by endoscopic biopsy. The MGC patients had larger tumours, a higher frequency of lymph node metastases, were more likely to have tumours of tumour, node, metastasis stages III and IV, and were less likely to have a curative resection than NGC patients. In addition, five MGC patients had calcifications in the thickened gastric wall. In conclusion, MGC is rare and is detected mostly at an advanced stage. The diagnostic sensitivity of MGC by endoscopic biopsy was relatively low, whereas MDCT was helpful in distinguishing MGC from NGC.

We describe a new salt-assisted aero-sol−gel approach to produce spherical nanosized mesoporous silica particles. As an alternative to expensive templating mediums in prior works, salt (NaCl) was employed as a templating medium because it is thermally stable, recyclable, and easily leached. Furthermore, we demonstrate the ability to carry out traditional sol−gel chemistry within an aerosol droplet. The role of salt in sol−gel chemistry and aerosol processing was investigated as a function of hydrolysis time. It was verified that salt accelerates the kinetics of silica gelation, and simultaneously becomes an excellent templating medium to support nano-sized pores inside silica structures in the aerosol processing route. The presence of salt results in a roughly ten-fold increasing in the pore specific surface area and pore volume, subsequent to leaching of the salt matrix. The surface area and pore volume of the as-produced nanoporous silica particles was found to increase with increasing sol−gel hydrolysis time.

In this paper we describe a new approach for the formation of nanoporous particles in which a thermally stable, water-soluble, and therefore easily leached second component is employed during spray pyrolysis to produce a composite particle. We demonstrate the new synthetic approach for synthesizing nanoporous aluminum oxide (Al2O3) by spray pyrolysis of aluminum nitrate (Al(NO3)3·9H2O) and sodium chloride (NaCl) solutions. The characteristics of the nanoporous material such as surface area, pore volume, and particle morphology are investigated as a function of relative humidity, temperature, and salt fractions. Specific surface area of the product particles increased significantly from 10 m²/g for the produced composite particles to over 370 m²/g for the remaining Al2O3 particles following aqueous leaching to remove the NaCl filler. Nanoporous particles could be produced at relatively low temperature (<550 °C) and high relative humidity (or low evaporation rate of aerosolized droplets) when followed by the aqueous leaching process of final product powder. However, we observed only solid particles at reactor temperatures above 700 °C and residence times of about 1 s. We attribute this behavior to evaporation of salt from the composite particles as evidenced through particles size distribution measurements, which showed the formation of a nuclei mode at these temperatures. At these higher temperatures we suspect a collapse of the porous network in the absence of the supporting salt network and results in particles with low surface area. Intermediate levels of salt fractions result in the formation of nanoporous particles, while high salt fractions result in a loosely connected network and the formation of individual nanoparticles in the salt matrix.

The low-resolution microwave spectra of 2,2,2-trichloroethyl methyl ether have been recorded from 26.5 to 39.0GHz. From the spacing of the major bands, it is shown that the value of 2065.4MHz for B+Cis consistent with the presence of the gaucheconformer. Another set of bands of approximately two-third the intensity of the major bands has also been observed. The value of 1996.5MHz for B+Cis consistent with the presence of the transconformer. The microwave data indicate that the gaucheconformer is the abundant one in the gas phase. Interpretation as to the dominance of the gaucheconformer will be suggested.

Empirical soil erosion models continue to play an important role in soil conservation planning and environmental evaluations around the world. The effect of hillslope length on soil loss, often termed the slope length factor, is one of the main and most variable components of any empirical model. In the most widely used model, the Universal Soil Loss Equation (USLE), normalized soil loss, L, is expressed as a power function of slope length, λ, as L=(λ/22.1)m, in which the slope exponent, m, is 0.2, 0.3, 0.4, and 0.5 for different, increasing slope gradients. In the Revised Universal Soil Loss Equation (RUSLE), the exponent, m, is defined as a continuous function of slope gradient and the expected ratio of rill to interrill erosion. When the slope gradient is 60% and the ratio of rill to interrill erosion is classified as moderate, the exponent mhas the value of 0.71 in RUSLE, as compared with 0.5 for the USLE. The purpose of this study was to evaluate the relationship between soil loss and slope length for slopes up to 60% in steepness. Soil loss data from natural runoff plots at three locations on the Loess Plateau in China and data from a previous study were used. The results indicated that the exponent, m, for the relationship between soil loss and the slope length for the combined data from the three stations in the Loess Plateau was 0.44(r2=0.95)For the data as a whole, the exponent did not increase as slope steepness increased from 20 to 60%. We also found that the value of mwas greater for intense storms than for less intense storms. These experimental data indicate that the USLE exponent, m=0.5, is more appropriate for steep slopes than is the RUSLE exponent, and that the slope length exponent varies as a function of rainfall intensity.

A new aerosol generator for particles below 10 nm is presented. Its working principle is based on an evaporation and subsequent cooling process in a mixing jet. A theoretical evaluation of this generation process allows the determination of the influence of key parameters on the concentration expected and, moreover, facilitates the prediction of the final particle size and distribution function. The experimental verification shows good agreement with the theoretical prediction for the particle size and distribution width.

An optical particle counter has been calibrated for size distribution measurement of airborne coal dust particles. A differential electrical mobility analyzer was used with a fluidized bed dust feeder to produce uniform coal dust particles of a known size for calibration for particles <2.4 μm. For larger particles, the optical counter was calibrated with a microscopic technique. The output pulse height of the optical counter was found to be significantly lower for coal particles than for spherical oil drops of the same particle size. The geometrical standard deviation, σg, of the output pulse height distribution of the optical counter for monodisperse aerosols was found to increase from about 1.1 for spherical oil particles to about 1.8 for the irregularly shaped coal particles. Although this broadening effect reduced the ability of the counter to resolve small particle size differences, a numerical inversion procedure was developed which allowed the original size distribution to be recovered.

A system for sampling aerosols in the facepiece of a powered air purifying respirator has been described. The system consists of a sampling inlet mounted on the respirator facepiece, a filter cassette and a personal sampling pump. The theoretical and practical considerations leading to the design of the sampling inlet have been discussed and experimental data presented showing the efficiency of the inlet as a function of particle size and sampling flow rate. The in-mask sampling system has been designed for powered air purifying respirators.

A theoretical analysis of filtration mechanisms has been made for fibrous filters in the region of maximum penetration. The theory is based on a boundary layer approach using the Kuwabara flow field to account for the interference effects of neighboring fibers. An improved expression for the diffusion and interception filtration efficiencies has been derived that compares well with the existing theories. A comparison of the developed theory with experimental data also confirms the validity of the present work.

This paper describes theoretical and experimental studies undertaken in connection with the problem of sampling carbon fiber aerosols in an ambient environment. Calculations indicate that carbon fiber aerosols with an 8-μm fiber diameter and a density of 1.8 g/cm3 can be sampled by a sampler designed to collect particles in the 10-30-μm aerodynamic diameter range if fibers up to a few millimeters in length are to be collected. An approach is then described in which carbon fiber aerosols are collected in the impactor of the inlet of a dichotomous sampler. Experimental data are presented showing that the impaction characteristics of the carbon fiber aerosol can be predicted with a reasonable degree of accuracy by approximating the shape of the fibers by a prolate ellipsoid.

The population balance equations for simultaneous coagulation and deposition of free molecule aerosols in turbulent pipe flow have been cast in dimensionless form and integrated to obtain a simplified two-equation model. The relative importance of coagulation and deposition is shown to depend upon a dimensionless parameter A, which is a ratio of a characteristic deposition time to a characteristic coagulation time. Solutions to these equations are presented graphically and range from the coagulation-dominated to the deposition-dominated regime. This analysis accounts for the enhancement in coagulation rates due to London-van der Waals attractive forces; this effect is often important for free molecule aerosols. In a separate paper (Brockmann et al., 1982) experimental data are shown to be in good agreement with theoretical predictions.

A data inversion procedure for the electrical aerosol analyzer, based on a simplex minimization algorithm, is described. The method has been tested extensively using data which were generated by a numerical simulation of the instrument's response for a wide range of various unimodal and bimodal log-normal distributions. The sensitivity of the procedure to random errors in the measured data as well as in the response matrix elements has been checked. The application of the program to data from atomizer-generated test aerosols is demonstrated.

Submicron aerosol filtration by fibrous filters has been studied experimentally employing a filter efficiency measuring technique based on the use of moderately monodisperse aerosols and an electrical aerosol detector. Using this technique, the filtration efficiencies of filters made of uniformly sized fibers have been measured by the use of particles in the 0.035-1.3 μm diameter range. Filter solidity has ranged from 0.0086 to 0.42. Filtration velocity has been varied between 1 and 300 cm/sec. The results of the measurement have been compared quantitatively with the available theories. It has been found that theories taking into account the interference effect of neighboring fibers are in reasonable agreement with the experiments.

A tropane ester, three tropane ethers, atropine and mecamylamine were compared in mice for their anti‐muscarinic and anti‐nicotinic activity against arecoline‐induced tremor and nicotine‐induced convulsions, respectively. Their receptor‐binding characteristics were studied in neuronal membranes prepared from rat cerebral cortex.

The herpes simplex virus DNA polymerase catalytic subunit, which has intrinsic polymerase and 3'-5' exonuclease activities, contains sequence motifs that are homologous to those important for 3'-5' exonuclease activity in other polymerases. The role of one such motif, Exo III, was examined in this study. Mutated polymerases containing either a single tyrosine-to-histidine change at residue 577 or this change plus an aspartic acid-to-alanine at residue 581 in the Exo III motif exhibited defective or undetectable exonuclease activity, respectively, yet retained substantial polymerase activity. Despite the defects in exonuclease activity, the mutant polymerases were able to support viral replication in transient complementation assays, albeit inefficiently. Viruses replicated via the action of these mutant polymerases exhibited substantially increased frequencies of mutants resistant to ganciclovir. Furthermore, when the Exo III mutations were incorporated into the viral genome, the resulting mutant viruses displayed only modestly defect in replication in Vero cells and exhibited substantially increased mutation frequencies. The results suggest that herpes simplex virus can replicate despite severely impaired exonuclease activity and that the 3'-5' exonuclease contributes substantially to the fidelity of viral DNA replication.

A continuous-flow, evaporation-condensation aerosol generator has been designed to produce particles of practical monodispersity of stearic acid in concentrations of over 1 g/m3 at flow rates > 6 L/min. Pure stearic acid containing a dissolved impurity is melt-sprayed and evaporated, producing a nuclei- vapor mixture. The mixture is recondensed and then quickly quenched into spherical, solid particles of a narrow size distribution. The condenser design is a straight, insulated glass tube of 5 cm in inner diameter and of 110 cm in length. A heating and flow straightening conditioning section previous to the condenser provides a relatively flat condensation front across the tube diameter, while the insulated condenser walls in free convection create a low radial temperature gradient, both of which enhance particle monodispersity with particle geometric standard deviations < 1.25. The dynamic condenser conditions for the suppression of homogeneous nucleation were investigated as a function of the ratio of the Grashof-Prandtl numbers product to the Reynolds number.

A theoretical study has been carried out to investigate the performance of the TSI 3020 condensation nucleus counter (CNC) at various pressures and flow rates by assuming a parabolic velocity profile in the condenser tube and solving the heat and mass transfer equations using the finite difference method. Calculations have been performed for pressures ranging from 0.03 to 10 atm and sampling flow rates from 0.5 to 50 mL/s. The results indicate that the counting efficiency of the CNC is a function of pressure and flow rate due to changes in heat and mass transfer rates. The counting efficiency can be correlated with a single parameter, ζ, which combines the effects due to pressure, sampling flow rate, and the length and diameter of the condenser tube. The cut size of the instrument, Dp50, defined as the particle size at which the counting efficiency is 50%, has been found to vary with pressures, reaching a minimum at a pressure of approximately 1 atm. The cut size of the CNC has been found to be most sensitive to the temperature difference between the saturator and condenser but relatively insensitive to the flow rate and the saturator temperature.

An in situ particle flux monitor (High Yield Technology, Inc., model PM-100) was evaluated using monodisperse polystyrene latex and oleic acid aerosols. A conventional laser particle counter with a lower size limit of 0.3 μm was used to obtain efficiency data. The counting efficiency of the monitor was determined experimentally as a function of particle size in the diameter range of 0.5-6.0 μm. Other operating characteristics that were studied include the effect on counting efficiency of particle velocity, spatial uniformity of the viewing plane, aerosol concentration, and discriminator setting. In addition, the application of the monitor in a vacuum environment was demonstrated. Results showed that the monitor counting efficiency decreased with particle size (from 4.7% at 6 μm to 0.1% at 0.5 μm). Also, the counting efficiency was found to be dependent on sampling velocity but was unaffected by particle concentration. Further tests showed that the monitor had limited sizing ability. Mie scattering analysis of the sensor geometry suggested that the sensor performance could be improved by modifying the sensor sampling geometry and laser beam configuration. Although the counting efficiency of the monitor is lower than that of a conventional laser particle counter, the small size of the sensor makes it a useful process-monitoring tool (see Borden et al., 1987).

During the 1979 workshop of the working group on ultrafine aerosols, different experimental techniques for measuring the number concentration and size of ultrafine aerosol particles were compared. In the present paper we report on a comparison of different particle size measuring techniques for ultrafine aerosols. Well-defined monodisperse aerosols with electrical mobility particle diameters ranging from 13 to 100 nm were generated using an electrical aerosol classifier. Kelvin-equivalent size distributions of these aerosols were determined by means of a process-controlled expansion chamber, the size-analyzing nuclei counter (SANC). To this end the considered aerosol was humidified and the number concentration of the droplets growing in the expansion chamber was measured for stepwise increase in supersaturation. At a quite well defined critical supersaturation, a significant increase in the measured droplet concentration, and thus the onset of heterogeneous nucleation, was observed. By means of the Kelvin-Gibbs equation this critical supersaturation is related to the Kelvin-equivalent diameter of the aerosol particles. Measurements were made on NaCl and dioctyl phthalate (DOP) aerosols. For NaCl particles the Kelvin diameter was found to be larger by a factor of about 4 than the electrical mobility diameter, as determined by the electrostatic aerosol classifier. This is explained by the solubility of the NaCl particles. For DOP particles, however, the Kelvin diameter agrees quite well with the electrical mobility diameter. The Kelvin size distributions were found to be quite narrow, indicating a high monodispersity of the generated aerosol as well as a satisfactory size resolution of the SANC. Thus different experimental techniques, based on completely different principles, yielded similar measurement results.

A diluter that was designed for sampling high concentrations (∼ 1010 cm-3) of ultrafine aerosols (particle diameter smaller than 0.02 μm) is described. Particular care was taken to minimize the effects of coagulation and diffusional deposition within the diluter. Furthermore, the diluter was designed so that the effects of these processes on the size distribution of the sampled aerosol can be calculated. Provision was made to monitor continuously flow rates of the aerosol sample and dilution air. With these flow measurements, dilution ratios can be calculated without recourse to empirical calibrations that may change with time. In its present configuration, it can achieve dilution ratios ranging from 300 to 4000; this range could be extended with minor modifications. In this paper the procedure that was used in designing the diluter is described, and the performance of the diluter is compared with design expectations.

The nature of the antagonism by anticholinergic compounds of nicotine-induced convulsion in mice has not been defined clearly. Although, because they do not compete effectively for agonist binding to brain tissue in-vitro, these compounds are thought to be non-competitive antagonists in the brain, pharmacological evidence is lacking. This study describes the anti-nicotinic properties of the clinically used anticholinergic antiparkinson drugs, benztropine, biperiden, caramiphen, ethopropazine, procyclidine and trihexyphenidyl.Nicotine-induced convulsion and arecoline-induced tremor in mice were effectively prevented by these drugs. The concentrations of benztropine, biperiden, caramiphen, ethopropazine, procyclidine and trihexyphenidyl affording 50% prevention of nicotine-induced convulsion (ED50 values) were 7.4, 4.6, 7.8, 4.9, 3.1 and 3.3 mg kg−1, respectively. The classical muscarinic receptor antagonist atropine had potent anti-muscarinic effects but very weak anti-nicotinic activity. The classical nicotinic receptor antagonist mecamylamine had potent anti-nicotinic activity but no anti-muscarinic effects. The pattern of shift of the dose-response curve for nicotine-induced convulsion in mice was determined in the presence of increasing concentrations of the anticholinergic antiparkinson drugs. These drugs were found to increase the ED50 (0.49 mg kg−1) of nicotine-induced convulsion in a dose-related manner. The maximum effect of nicotine and the slope of nicotine dose-response curve were not significantly influenced by either low or high doses of benztropine, procyclidine or trihexylphenidyl, which suggests competitive action. Biperiden, caramiphen and ethopropazine, at low doses which significantly increased the ED50 of nicotine, did not affect the maximum effect of nicotine or the slope of the nicotine dose-response curve; at higher doses, however, they reduced the maximum effect and the slope, which suggests that these drugs have both competitive and non-competitive properties in antagonizing nicotine-induced convulsion in mice.The experiments demonstrate that the anticholinergic antiparkinson drugs and mecamylamine effectively antagonize nicotine-induced convulsion, but atropine does not; some of these drugs have competitive properties whereas others seem to have both competitive and non-competitive properties in antagonizing nicotine-induced convulsion in mice.

The flow field in an inertial impactor was studied experimentally with a water model by means of a flow visualization technique. The influence of such parameters as Reynolds number and jet-to-plate distance on the flow field was determined. The Navier-Stokes equations describing the laminar flow field in the impactor were solved numerically by means of a finite difference relaxation method. The theoretical results were found to be in good agreement with the empirical observations made with the water model.

The nature of the antagonism by anticholinergic compounds of nicotine‐induced convulsion in mice has not been defined clearly. Although, because they do not compete effectively for agonist binding to brain tissue in‐vitro, these compounds are thought to be non‐competitive antagonists in the brain, pharmacological evidence is lacking. This study describes the anti‐nicotinic properties of the clinically used anticholinergic antiparkinson drugs, benztropine, biperiden, caramiphen, ethopropazine, procyclidine and trihexyphenidyl.

The geometrical accuracy of a real solar concentrator is defined quantitatively in terms of two equivalent parameters: the standard target error and the angular error; and the relationships between these parameters and the flux distribution on the focal plane are developed. A general method for determining the optimum size and efficiency of an absorber for any given concentrator is described. Specific numerical results are obtained; however, only for the case where the function describing the flux distribution on the focal plane is given by Gauss’ normal law of error. Criteria for determining the applicability of the results are proposed. Finally, experimental techniques (both optical and thermal) of evaluating concentrators are briefly described.

This study was designed to investigate whether the size of the largest lymph node (long-axis diameter [LAD] and short-axis diameter [SAD]) visualized using multi-detector-row computed tomography (MDCT) was useful for predicting the metastatic lymph node (MLN) status of gastric cancer. A retrospective analysis of 305 gastric cancer patients who underwent pre-operative MDCT was performed, followed by a prospective study in 61 gastric cancer patients to determine the diagnostic effectiveness of LAD and SAD. In the retrospective study, the accuracy of LAD and SAD for predicting the MLN status of gastric cancer was 51.1% and 45.9%, respectively. In the prospective study, the accuracy of LAD and SAD measurement and the traditional MDCT method of counting MLNs was 52.5%, 49.2% and 57.4%, respectively; the differences were not significant. In conclusion, the size of the largest lymph node in terms of LAD and SAD visualized on MDCT was useful for predicting the MLN status of gastric cancer, with accuracy comparable to the traditional MDCT method of counting the total number of MLNs detected.