Horizontal Screening Research Articles

Dynamic visual acuity screening test results analysis of 25 patients with peripheral vertigo

Objective:To observe the results of dynamic visual acuity screening tests in patients with peripheral vertigo and explore its clinical significance. Methods:The number of 48 healthy volunteers were enrolled as control group and 25 peripheral vertigo patients as experimental group. In the experimental group, there are 12 patients with vestibular neuritis, 1 patient with Hunt syndrome, 5 patients with sudden deafness with vertigo and 7 patients with bilateral vestibular dysfunction. Horizontal and vertical dynamic visual acuity screening tests were performed on them. The number of lost rows of horizontal and vertical dynamic visual acuity was compared between the control group and the experimental group to figure out if there is a statistical difference. The number of lost rows of horizontal and vertical dynamic visual acuity was compared within the experimental group to figure out if there is a statistical difference. The two groups of 18 cases of unilateral vestibular function decline and 7 cases of bilateral vestibular function decline in the experimental group were compared with the control group, and figure out if there is a statistical difference. Results:The median number of lost rows of horizontal dynamic visual acuity in 48 healthy volunteers was 1.5 and median number of lost rows of vertical dynamic visual acuity was 1.0 in the control group. The median number of lost rows of horizontal dynamic visual acuity of 26 healthy volunteers was 6 and median number of lost rows of vertical dynamic visual acuity was 5 in the experimental group. Compared to the experimental group, the number of lost rows both have statistical significance in horizontal and vertical dynamic visual acuity（P<0.01）. The comparison of horizontal and vertical lost rows within the test group also have statistical significance（P<0.01）. Twenty five patients with exceptional vestibular disease in the experimental group were divided into unilateral vestibular function reduction group（n=18） and bilateral vestibular function reduction group（n=7）. Compared with the control group, there was significant differences in the number of horizontal and vertical lost rows（P<0.01） within the three groups. After pairwise comparison, the number of lost rows of horizontal and vertical in the control group was significantly lower than that in the unilateral vestibular function reduction group and the bilateral vestibular function reduction group（P<0.01）. There was a highly significant correlation between the number of horizontally lost rows of DVA and the mean vHIT values of bilateral horizontal semicircular canals in 25 patients（P<0.01）; and a highly significant correlation between the number of vertically lost rows of DVA and the mean vHIT values of vertical semicircular canals in 4 groups bilaterally（P<0.01）. Conclusion:The Dynamic Visual Acuity Screening Test is a useful addition to existing tests of peripheral vestibular function, particularly the vHIT test, and provides a rapid assessment of the extent of 2 Hz VOR impairment in patients with reduced vestibular function.

The influence of the parameters of a vibration separator with a horizontal sieves layering on the intensity of separation

To conduct a research, a vibration separator with horizontal screening was selected. It is characterized by simplicity of design and service, low sensitivity to the properties of the mixture being separated, variety of forms of oscillation, the possibility of automated unloading of the resulting fractions of the granular mixture and automation of the separation process. First of all, a nonlinear mathematical model for describing the motion of a separator with horizontal sieve layout with the use of asymptotic methods of nonlinear mechanics and the Lagrange equation is constructed. The model represents a system of analytic dependencies of coordinate functions of points of a separator sieves system by its kinematic, geometric and power parameters. These dependencies made it possible to investigate the influence level of the indicated parameters of the separator on the intensity factors of the separation process, in particular on the amplitude of the oscillatory motion of the horizontally laid sieves. The results of the research should be applied at both stages of the design of a vibration separator with horizontal screening of sieves and with the choice of parameters and modes of its operation.

Разработка сверхвысокочастотной установки контейнерного типа для термообработки крови и жиросодержащего сырья

A microwave installation was created to boil waste products of poultry and animal slaughtering in a periodic mode. It consists of a horizontal cylindrical screening body. Inside it a perforated disc-rotor from non-ferromagnetic material, rotating the motor is installed. The cylindrical resonators are rigidly fixed on the periphery of the disc-rotor. Inside each resonator the removable dielectric heat resistant containers are mounted by clamps, which covers are perforated. The inner surface of the containers is covered with a silicone material. Microwave generator units are installed on the cover of shielded enclosure, opening with handles by hinges. At the base of the body there is a drain connection. To justify structurally and technological parameters of microwave installation we analyzed the changes in the electrical parameters of the muscle tissue, skin, bone, fat, depending on the frequency of electromagnetic fields exposure. The permittivity changes of raw materials, wavelength in the feed, penetration depth of electromagnetic radiation in the feedstock were also analyzed. The effect volume heating of inedible waste in the electromagnetic field is achieved due to penetration of the field into the feed to a considerable depth. At a certain depth of penetration it becomes possible to prove the form of processed raw material in resonator depending upon the requirements of the process and electromagnetic field parameters. The temperature and conductivity of the material greatly influence to the penetration depth.

Comparing Vertical and Horizontal Screening Methods for Pharmacy Resident Candidates Before Interviews

Purpose: Prior studies have examined autobiographical screening methods among medical student applicants, and demonstrated halo bias with single-rater scoring; though others have questioned its practical significance. Comparing with traditional vertical screening method, we evaluated a horizontal method for initial screening of Post-Graduate Year-1 (PGY-1) pharmacy practice resident candidate applications prior to interviews.&#x0D; Methods: Our screening rubric for PGY-1 pharmacy residency candidates consisted of eight criteria, each scored using a 5-point Likert scale. During the 2014 residency recruitment season, two single-evaluators (A&amp;B) scored all eight criteria and their scores were summed into total application scores (vertical method). Meanwhile two other evaluators (C&amp;D) each evaluated only two criteria for all applications. The four combined-evaluators (A-D) scores, on two criteria each, were summed together into total application scores (horizontal method). For statistical comparison of single-evaluator and combined-evaluators, inter-component reliabilities were analyzed for each evaluator, while inter-rater consistency was also examined. For practical significance, actual selection differences were reviewed.&#x0D; Results:Forty-six applications were evaluated to determine 24 invitations for on-site interviews. Inter-component reliability differed among evaluatorA, evaluatorB, combined-evaluators A-D (Cronbach’s alpha of 0.74, 0.73, 0.58, respectively; lower better). Among raters, inter-rater consistency was excellent (0.86 by intraclass correlation, p&#x0D; Conclusion: Halo bias was seen with the single-evaluators (vertical method); two interview invitations were negatively impacted. For pharmacy resident screening, a horizontal screening method appears to be rigorous in promoting fairness for applicants. As pharmacy residency applications continue to grow, a fair and time-efficient method of screening seems imperative.&#x0D; &#x0D; Type: Original Research

The horizontal amplitude screening effects of a rectangular strip in-filled trench

The horizontal amplitude screening effects of an in-filled trench are solved using the boundary element method in the frequency domain. Dimensionless parametric studies are performed to assess the screening effects of the trench in terms of the geometry, in-filled material, foundational embedment, and shear wave velocity ratio of the in-filled material to the surrounding soil. The results show that the screening effects of the in-filled trench depend highly on the trench geometry and the velocity ratio of the in-filled material to the surrounding soil. The embedment ratio of the foundation and other factors are relatively unimportant.

Effect of Centrifugal Forces on the Interparticle Distance of Two Dust Particles Confined in a Plasma

Dusty-plasma experiments with flat dust clusters are often performed in radio frequency discharges at typical gas pressures of 1 to 100 Pa. For the understanding of the structure and the dynamical behavior of dust clusters, the grain charge and the effective Debye length are of key interest. Direct measurements of these quantities are a challenging task because the dust grains are confined in the plasma-boundary layer, where plasma diagnostics is difficult. Here, we present a new approach to determine the grain charge and the horizontal screening length, which does not require prior knowledge of the plasma parameters. The method is based on a slow and controlled rotation of the neutral-gas column due to a rotating electrode. This leads to centrifugal forces to the dust grains without changing the plasma conditions and allows studying the interparticle distance of a dust cluster as a function of its rotation frequency, which directly depends on the particle charge, the screening length, and the strength of the confining potential.

Habitat Quality Following Mid‐Rotation Treatment in Conservation Reserve Program Pines

ABSTRACT Evaluation of habitat management practices at mid‐rotation is needed for pine (Pinus spp.) plantations enrolled in cost‐share programs. Plantations established in abandoned agricultural fields may have different understory plant communities than those with a long history of forest cover. Mid‐rotation pine plantations often have a hardwood midstory that limits development of early succession habitat components important to white‐tailed deer (Odocoileus virginianus; deer) and northern bobwhite (Colinus virginianus; bobwhite). We treated with imazapyr herbicide and prescribed burning (HB) 11 thinned, 13–22‐year‐old pine plantations in the Upper East Gulf Coastal Plain of Mississippi, USA, enrolled in cost‐share programs, and we sampled plant community response during the summers of 2003 and 2004, years 1 and 2 posttreatment. The HB treatment created a more open structure with greater coverage of debris and herbaceous plants than in controls. Increased forb coverage in HB plots yielded a more seasonally diverse foraging base for deer. Horizontal screening cover developed slowly in HB plots and was more abundant in control plots. Autumn and winter food‐plant coverage for bobwhite was provided by either treatment, but accessibility was improved in HB plots relative to controls. Bobwhite nesting cover was improved by HB relative to controls but was still of marginal quality. Brood‐rearing habitat was precluded in both treatments due to lack of bare ground. Our results indicate that imazapyr followed by prescribed fire is a beneficial tool for creating early succession habitat for deer and bobwhite in mid‐rotation pine plantations with a history of agricultural use. Continued management with periodic prescribed fire and overstory thinning should be instituted to maintain and perhaps improve these conditions.

Methods for size classification of wood chips

Abstract Methods for size classification of wood chips were analysed in an international round robin using 13 conventional wood chip samples and two specially prepared standard samples, one from wood chips and one from hog fuel. The true size distribution of these two samples (according to length, width and height) had been determined stereometrically (reference method) using a digital calliper gauge and by weighing each of the about 7000 wood particles per sample. Five different horizontal and three rotary screening devices were tested using five different screen hole diameters (3.15, 8, 16, 45, 63 mm, round holes). These systems are compared to a commercially available continuously measuring image analysis equipment. The results show that among the devices of a measuring principle—horizontal and rotary screening—the results are quite comparable, while there is a severe incompatibility when distributions are determined by different measuring principles. Highest conformity with the reference values is given for measurements with an image analysis system, whereas for all machines with horizontal screens the median value of the size distribution only reached between one-third to half of the reference median value for the particle length distribution. These deviations can be attributed to a higher particle misplacement, which is particularly found in the larger fractions. Such differences decrease when the particle's shape is more roundish (i.e. sphericity closer to one). The median values of length distributions from screenings with a rotary classifier are between the measurements from an image analysis and horizontal screening devices.

Laser manipulation of particles in dusty plasmas

The technique of laser manipulation of individual dust particles instrongly coupled dusty plasmas is presented and its application to differenttypes of experiments is demonstrated. The laser manipulation has been used toexcite horizontal compressional waves and Mach cones which are used to derivethe horizontal particle interaction and screening strength. Lasers are alsoused to excite collective modes in finite Coulomb clusters (`artificialatoms'). From the laser excitation of vertical oscillations in the sheath ofan rf discharge the dust particle charge is measured. Moreover, the verticalinteraction between dust particles is shown to be non-reciprocal andattractive due to the ion streaming motion in the sheath where the dustparticles are trapped.

Vegetation Characteristics Influencing Site Selection by Male White-Tailed Deer in Texas

We studied the effects of vegetation characteristics in southern Texas on site selection by mature, male white-tailed deer (Odocoileus virginianus Raf.). Thirteen, radio-collared animals were monitored during winter, spring, summer, and fall of 1986-87 and 1987-88 to determine area-usage patterns within each animal's respective seasonal home range. After each season, structural vegetation attributes were measured with transect-oriented data collection techniques inside the most heavily used and unused areas of each animal's home range. Comparisons were made between these areas to determine whether site selection by deer was in response to differing vegetation characteristics. In general, the most heavily used areas possessed a greater amount of woody canopy cover (greater than or equal to 85%), woody species richness (18-20), and horizontal screening cover than areas with no use. In contrast, herbaceous densities did not differ between the most heavily used and unused areas. Consequently, habitat management manipulations conducted specifically for mature male white-tailed deer in southern Texas, should include provisions for creation or maintenance of sites possessing dense woody canopy cover, a high number of woody species and dense horizontal screening cover.

Closure to “ Design of Wave Barriers for Reduction of Horizontal Ground Vibration ” by Tahmeed H. Al‐Hussaini and Shahid Ahmad (April 1991, Vol. 117, No. 4)

Wave barriers are often installed in the ground to reduce high-frequency ground vibrations induced by man-made sources such as traffic or machine foundations. This type of ground vibration could be a major problem in densely populated urban areas and for structures housing sensitive equipments. This paper investigates the effectiveness of rectangular wave barriers (solid obstacles) in reducing the horizontal ground vibration caused by propagating surface waves. A rigorous boundary element method (BEM) algorithm incorporating higher-order elements is used to conduct an extensive numerical study of the influence of various key geometrical and material parameters on the screening efficiency of a rectangular barrier. Important dimensionless parameters are identified. Based on the influence of these parameters, a simple model is developed for the design of wave barriers for horizontal vibration screening. Finally, some numerical examples are presented and through comparisons with results from the rigorous BEM technique, the applicability and usefulness of the developed model is established.

Design of wave barriers for reduction of horizontal ground vibration : J Geotech Engng Div ASCE V117, N4, April 1991, P616–636

Wave barriers are often installed in the ground to reduce high-frequency ground vibrations induced by man-made sources such as traffic or machine foundations. This type of ground vibration could be a major problem in densely populated urban areas and for structures housing sensitive equipments. This paper investigates the effectiveness of rectangular wave barriers (solid obstacles) in reducing the horizontal ground vibration caused by propagating surface waves. A rigorous boundary element method (BEM) algorithm incorporating higher-order elements is used to conduct an extensive numerical study of the influence of various key geometrical and material parameters on the screening efficiency of a rectangular barrier. Important dimensionless parameters are identified. Based on the influence of these parameters, a simple model is developed for the design of wave barriers for horizontal vibration screening. Finally, some numerical examples are presented and through comparisons with results from the rigorous BEM technique, the applicability and usefulness of the developed model is established.

Design of Wave Barriers for Reduction of Horizontal Ground Vibration

Wave barriers are often installed in the ground to reduce high‐frequency ground vibrations induced by man‐made sources such as traffic or machine foundations. This type of ground vibration could be a major problem in densely populated urban areas and for structures housing sensitive equipments. This paper investigates the effectiveness of rectangular wave barriers (solid obstacles) in reducing the horizontal ground vibration caused by propagating surface waves. A rigorous boundary element method (BEM) algorithm incorporating higher‐order elements is used to conduct an extensive numerical study of the influence of various key geometrical and material parameters on the screening efficiency of a rectangular barrier. Important dimensionless parameters are identified. Based on the influence of these parameters, a simple model is developed for the design of wave barriers for horizontal vibration screening. Finally, some numerical examples are presented and through comparisons with results from the rigorous BEM technique, the applicability and usefulness of the developed model is established.

Two Variations of a Salmonid Smolt Trap for Small Rivers

Abstract Trap nets were designed and constructed to capture steelhead smolts (Salmo gairdneri) that had been stocked as fry in two coastal streams of British Columbia. The traps were fabricated from knotless nylon netting material and had a horizontal screening section to cope with fluctuations in water flow and debris. The nets were suspended from cables from which they could be detached easily for cleaning or during extreme flows. The trap nets were used in flows of approximately 2.4 to 18.0 m 3/s on Lynn Creek and from 3.4 to 14.0 m 3/s on the Englishman River. Both nets remained operational at flows of approximately 10 m 3/s. In efficiency tests, 78.1 and 54.7% of the steelhead smolts released above the trap nets were captured in the Lynn Creek and the Englishman River traps, respectively. The nets were an effective and inexpensive means of fishing these streams. They provide an easily cleaned, large screening area and can be modified for other locations.