End Pieces Research Articles

Magnetic performance of the SSC dipole magnets

The authors report on the status of the magnetic design of the Superconducting Super Collider (SSC) dipole magnets. A two- and three-dimensional design optimization was performed that included the effects of permeable collar, yoke, cryostat, beam tube, crescent yoke end pieces, cool-down, and Lorentz loads. A field quality plan was developed that represents the approach to tuning the design for satisfying the systematic and RMS multipole specifications. The VSA tool is being used to simulate the effects of random parts, tool and process variations on the expected multipole distributions, both between many magnets, and within a single magnet. >

LONG-TERM STABILITY OF HAND-HELD DYNAMOMETRIC MEASUREMENTS IN CHILDREN WHO HAVE MYELOMENINGOCELE

The long-term stability of hand-held dynamometric measurements was assessed in 30 muscle groups of 12 children with myelomeningocele, before and after a 23-day interval. Measurements from a majority of the muscle groups had excellent stability, based on statistical indicators of association (Pearson Product-Moment Correlation Coefficients, r =.76-.98) and agreement (intraclass correlation coefficients, ICC = .75-.99). Muscle groups with lower long-term stability were the right and left wrist extensors and flexors, the left hip adductors and extensors, the left knee flexors, and the right and left knee extensors. Upper-extremity muscle groups had higher long-term stability than did lower-extremity muscle groups. The results indicate that the dynamometric measurements were highly reliable when the test-retest interval was 23 days. Other researchers have previously shown high reliability for these measurements over shorter periods of time. Improved reliability might be obtained by supporting the lower extremity during hip extension tests; padding the dynamometer end pieces, especially when testing over bony prominences; and using a smaller, digital dynamometer. The hand-held dynamometer appears to warrant use and further investigation with pediatric populations.

Morphological observations on the harderian gland of the North American opossum (Didelphis virginiana).

The Harderian gland of the North American opossum (Didelphis virginiana) is large and well developed, despite the absence of a nictitating membrane in the adult of this species. The elongate glands are surrounded by a delicate connective tissue capsule from which thin septae extend, subdividing the gland into numerous lobules. The secretory units of the opossum Harderian gland are drained by a well defined but not extensive intralobular and interlobular duct system. Most of the secretory end pieces consist of tubulo-alveolar units with widely dilated lumina filled with secretory product. Numerous intact lipid vesicles suspended within an amorphous material constitute the luminal contents. Cells lining the tubulo-alveolar secretory end-pieces are usually columnar in shape, and characterized by numerous lipid-containing secretory vesicles and aggregations of poly-tubular complexes 40-60 nm in diameter. In addition, these cells contain numerous large irregularly shaped mitochondria, whose matrix is of considerable electron density. Intralobular and interlobular ducts are lined by electron-lucent epithelial cells that lack both the lipid-containing vesicles and the large mitochondria, although typical smaller mitochondria are found scattered within the cytoplasm. Both secretory end-pieces and ductal elements are invested by an abundance of myoepithelial cells. A second, smaller serous type of secretory unit may occur near the centre of some Harderian gland lobules. In these units secretory tubules and acini are compactly arranged surrounding a narrow lumen. Serous cells are pyramidal in shape and the cytoplasm is characterized by numerous electron-dense secretory granules and scattered profiles of rough endoplasmic reticulum.(ABSTRACT TRUNCATED AT 250 WORDS)

Long-term stability of hand-held dynamometric measurements in children who have myelomeningocele.

The long-term stability of hand-held dynamometric measurements was assessed in 30 muscle groups of 12 children with myelomeningocele, before and after a 23-day interval. Measurements from a majority of the muscle groups had excellent stability, based on statistical indicators of association (Pearson Product-Moment Correlation Coefficients, r =.76-.98) and agreement (intraclass correlation coefficients, ICC = .75-.99). Muscle groups with lower long-term stability were the right and left wrist extensors and flexors, the left hip adductors and extensors, the left knee flexors, and the right and left knee extensors. Upper-extremity muscle groups had higher long-term stability than did lower-extremity muscle groups. The results indicate that the dynamometric measurements were highly reliable when the test-retest interval was 23 days. Other researchers have previously shown high reliability for these measurements over shorter periods of time. Improved reliability might be obtained by supporting the lower extremity during hip extension tests; padding the dynamometer end pieces, especially when testing over bony prominences; and using a smaller, digital dynamometer. The hand-held dynamometer appears to warrant use and further investigation with pediatric populations.

Frequency characterization of a thin linear antenna using diakoptic antenna theory

A frequency-dependent analytical expression for the input impedance of a thin wire antenna is obtained using diakoptic theory. The linear antenna is diakopted into electrically short segments, where each is treated as a component with two terminals (except for end pieces, which have only one terminal). An impedance matrix is found which characterizes coupling between all segments. By expanding the free-space Green's function in a power series in wavenumber k, each entry in the resultant impedance matrix is obtained as an explicit function of frequency. The input admittance is found as a ratio of two polynomials in wavenumber k. A more systematic approach for the solution of the input admittance is achieved by expanding both the unknown current vector and the Green's function in power series in k. Equating coefficients of like powers in k leads to a numerically efficient algorithm which is used to determine the input admittance as a function of frequency. Numerical results compare well with the input impedance obtained from a conventional integral equation solution.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

A magnetic concentrator, made from textured dysprosium, contributed up to 7.6 T

Ferromagnetic polycrystalline dysprosium cores made from a rod-billet by hydropressing were used in concentrators to contribute up to 7.6 T in the gap between two conical end pieces. In each end piece the plane of easy magnetization is inclined at an angle to the central axis of the concentrator. Because of its magnetic characteristics a concentrator with textured dysprosium exceeds the known concentrators made from rare-earth materials. With this concentrator in a superconducting solenoid a total field of 21.2+or-0.2 T was obtained. >

Infrastructure and Innervation of Water Buffalo (&lt;i&gt;Bubalus bubalis&lt;/i&gt;) Seminal Vesicle

The lining epithelium of secretory end pieces and central glandular duct in the seminal vesicle of the water buffalo (Bubalus bubalis) consists of columnar principal and small polymorphous basal cells. A system of intercellular and even intracellular canaliculi enlarges the secretory surface. The most prominent organelle of the columnar principal cells is the granular endoplasmic reticulum, forming large aggregates of parallel lamellae. Using antibodies against the neural cell adhesion molecule L1 and the neural marker protein gene product 9.5 (PGP 9.5), the innervation pattern of the seminal vesicle becomes evident. The muscular layer surrounding the propria contains a dense network of unmyelinated fibers. Thicker bundles traverse the muscular layer to reach the propria. Around glandular secretory tubules and below the epithelial lining of the glandular duct a tightly woven subepithelial plexus is observed which sends short penetrating branches into the basal zone of the epithelium. These intraepithelial nerves are devoid of Schwann cells and basal lamina (naked axons) and are situated within the intercellular spaces between principal and basal cells. Acetylcholinesterase histochemistry with short (1-2 h) incubation times, dopamine-beta-hydroxylase immunohistochemistry and ultrastructural study of transmitter-containing vesicles was performed. The results suggest that muscular contraction in the seminal vesicle is predominantly under the influence of the sympathetic nervous system, whereas secretory epithelial function is regulated by both sympathetic and parasympathetic fibers.

Lectin Histochemistry of Mucus-Secreting Cells in the Calf Bulbourethral Gland

The bulbourethral glands of 2-month-old calves were studied by means of lectin histochemical methods. The lectin-binding sites for each considered lectin can be divided into three groups according to their zonal topography. In the first group including PNA, MPA, RCAI, SBA and BPA binding sites were seen in most of the secreting tubules and end pieces. In the second group (WGA, GSI, DBA, UEAI and Con A) the reactive cells were limited to a reduced number of tubuloalveolar units generally located at the periphery of the gland. The third group was composed of two lectins, GSII and LTA for which the bulbourethral parenchyma was unreactive. These findings can be related to the glandular activity of the calf bulbourethral gland except for restricted peripheral areas with an appearing functional differentiation. This duality in the histochemical nature of glycoconjugates was compared with previous results obtained in other groups of mammals.

Factors modulating filament formation by bovine glial fibrillary acidic protein, the intermediate filament component of astroglial cells.

Glial fibrillary acidic protein (GFAP) is soluble in low ionic strength solutions but shows a strong tendency toward assembly with increasing ionic strength as revealed by electron microscopy and turbidity measurements. Increasing K+, Na+, and Li+ concentrations cause an increase followed by a decrease in GFAP turbidity with a maximum at 200 mM, but their effects are much weaker than effects of divalent cations at the same ionic strength. Ca2+, Mg2+, Mn2+, and Ba2+ promote assembly at millimolar concentrations, and 10 microM Cu2+ causes rapid aggregation. The critical concentration for GFAP assembly was 0.08 +/- 0.04 mg/mL in 2 mM Tris-HCl, 60 mM KCl, and 1 mM CaCl2, pH 6.8. The Mr 38,000 rod domain of GFAP obtained by limited chymotryptic digestion is more soluble in 100 mM imidazole hydrochloride buffer, pH 6.8, than the intact molecule, and removal of the end pieces greatly reduces the ability of GFAP to form filaments. BNPS-skatole (2-[(2-nitrophenyl)sulfenyl]-3-methyl-3-bromoindolenine) treatment releases a Mr 30,000 N-terminus and a Mr 20,000 C-terminus. The Mr 30,000 polypeptide shows a higher affinity than the Mr 20,000 fragment for intact GFAP. Arginine and lysine at low concentrations slightly accelerate GFAP assembly, but above 100 mM both amino acids inhibit assembly. ATP, GTP, CTP, and UTP do not show significant effects on GFAP assembly. Dephosphorylation by alkaline phosphatase slightly reduces the assembly ability of GFAP, but phosphatase-treated GFAP still is assembly competent.

Dermabrasive surgery state of the art

Except for refinements in equipment and instrumentation, the technique for dermabrasion essentially is unchanged from that described by Kurtin when he introduced the use of the wire brush in 1953. 1 Dermabrasive end pieces, usually a diamond fraise or the wire brush, rotating at high speeds from power-drive instruments, are surgically directed across skin that has been frozen to hardness with cryogenic spray. Both plastic surgeons and otolaryngologists with a plastic-surgery orientation have joined dermatologic surgeons in acknowledging the superior efficacy of this procedure as the profession's most versatile modality to resurface and recontour the skin successfully. From the early 1960s to the mid-1970s, dermabrasion was an innocent victim of unwarranted bad press. Most physicians and nearly all health insurance companies relegated its practicality to “cosmetic” enhancement of acne scars. Few training programs taught the procedure, and many physicians who attempted to perform it were inadequately prepared.

Lightweight ozonizer for field and airborne use

An efficient, lightweight apparatus for the production of ozone in flowing oxygen or air has been constructed and tested. The exciter is an automotive electronic ignition running from a 28-V dc power source. The discharge tube consists of coaxial conductive-coated flint glass tubing fitting into Teflon end pieces. A single such unit will produce 4% ozone in oxygen flowing at 0.2 l/min, or a maximum of 0.020 l of ozone per minute in a total flow of 1.0 l/min.

Factors Affecting Gas Slippage in Tight Sandstones of Cretaceous Age in the Uinta Basin

Summary The gas permeability of some sandstones from Uinta County, UT was measured in the laboratory. The effect of confining pressure and partial water saturation on gas permeability was investigated. Measurements were conducted at pressures of up to 34.5 MPa and partial liquid saturations of up to 60%. We noted that the slope of the straight lime relating apparent gas permeability to reciprocal mean pore pressure decreased with increasing net confining pressure and with increasing partial water saturation. Gas permeabilities extrapolated to infinite pore pressure were often higher than liquid permeabilities under the same confining pressure conditions; scanning electron microscopic (SEM) observations indicated rock/fluid interactions. Geologic studies of end pieces cut off from core plugs revealed that porosity is reduced by quartz overgrowths. authigenic clays (kaolinite. illite. and minor quantities of chlorite), carbonate cements (calcite and dolomite), and physical compaction of labile rock fragments. In some samples, organic-rich laminae were found to lie parallel to bedding surfaces. Apparently, micro porosity had been formed by partial leaching of feldspars and rock fragments. Most of the pores were lined with authigenic clays that form highly irregular pore walls. Thin film intergranular pores, which were observed in samples impregnated with blue epoxy at ambient pressure, were not found in samples in which the epoxy was cured under a confining pressure of 34.5 MPa. Introduction The concept of slip during gas flow through capillaries with diameters small enough to be comparable to the mean free path of the gas was used by Klinkenberg to explain the discrepancies between gas and liquid permeabilities of porous media. He presented the following equation, which relates the apparent gas permeability, kg, of a gas flowing at a mean pore pressure, to the true permeability of the porous medium, k g. ..........................(1) In this equation, b is a constant and is a function of the capillary radius, rb, and of the mean free path of the gas, at pressure . ...................................(2) In Eq. 2, c is a constant approximately equal to one. Loeb showed that Poiseuille's law for viscous flow can be modified to account for slip and defined a coefficient of slip that can be shown equal to the term c in Eq. 2. As is evident from Eq. 2, the contribution resulting from slip is inversely proportional to the capillary radius. At mean pore pressures usually employed in the laboratory measurements of permeability. the slip effect is significant in the case of tight sands because of the small pore sizes. The dependence of tight sandstone permeability on confining pressure and partial water saturation has been documented by numerous investigators. It appears reasonable, therefore, that the slip effect also would be affected by confining pressure and water saturation. A series of experiments was conducted in conjunction with petrographic observations in an attempt to understand the possible alterations in pore dimensions that result from confining stress and partial water saturation. Samples investigated were from Well MAPCO RBU 11-17 F (Section 17, T10S, R20E) in the Uinta Basin, UT. They are petrographically similar to other low-permeability sandstones of late Cretaceous age from the region.

The binding of sex steroids to human spermatozoa. An autoradiographic study.

The locations of steroid binding sites with specificities for 17 beta-oestradiol, progesterone and testosterone have been examined on human spermatozoa by autoradiography. The binding sites were not evenly distributed over the entire surface of human spermatozoa. They were more densely located on the midpiece of the tail, less on the head and neck, and least on the principal- and end pieces of the tail. The binding sites for 17 beta-oestradiol were specific, with 3H-17 beta-oestradiol being displayed by unlabelled 17 beta-oestradiol, but less readily displaced by either progesterone or testosterone. The binding sites for testosterone were less specific than those for 17 beta-oestradiol or those for progesterone. Both 17 beta-oestradiol and progesterone were good competitors for testosterone binding sites, while the binding of 3H-progesterone was easily displaced by 17 beta-oestradiol, but less readily displayed by testosterone. Since there was preferential binding of these steroids to the mid-piece, and strong competition for binding between 17 beta-oestradiol and progesterone, these studies appear to provide information on the sites of action for the reported effects of these and related steroids on spermatozoal motility, migration and metabolism.

Scots Pine, Pales Weevil and Northern Pine Weevil Control, Atwood, PA, 1980

Abstract A stand of 1.5-2.5m Scots pine Christmas trees was used for insecticide evaluation. The plantation had been partially harvested since 1976. Pretreatment weevil populations were noted prior to spraying by inspecting for adults attracted to trap logs made from end pieces of tree trunks left from the previous seasons harvest. Weevils were mating and feeding. A tree row with at least 6 new stumps (cut the previous fall) was treated as one replicate/treatment. Treatments were replicated 4 times in a randomized complete block design. Each stump received 4-6 oz spray consisting of insecticide in kerosene applied with a compression sprayer on April 25. Temperature was 10°C with wind 5 mph and overcast. The stumps were inspected (5 stumps per rep) on Sept 6 for chip cocoons following removal of bark to the first lateral root. Weevil cocoons were not identified to species.

Pales and Northern Pine Weevil Control on Scotch Pine, Atwood, Pa., 1979

Abstract A stand of 1.5 to 2 m Scotch pine Christmas trees was used for insecticide evaluation. The plantation was partially harvested in 1976 to 1978. Pretreatment weevil populations were noted on March 27'79 by inspecting for adults or stumps, trunk end pieces left from harvest, and in the duff. Pales and northern pine weevils were present and mating. A tree row with at least 7 new stumps (from trees cut the previous fall) was treated as one replicate within a block. Treatments were replicated 5 times in a randomized complete block design. Sprays were applied on April 17. Four to six ounces of insecticide mixed with kerosene (except Sevln UCSF 1 in water) were applied to each stump with a compressed air sprayer. Temperature was 10° to 12°C with wind being 3mph. Stump treatments were evaluated on October 25. The stumps (4 each of 5 replicates) were stripped of bark to the first lateral root and the chip cocoons counted. Weevil cocoons were not differentiated as to species.

Scotch Pine, Pales Weevil and Northern Pine Weevil Control, Atwood, PA, 1978

Abstract A stand of 1.5-2m Scotch pine Christmas trees was used for insecticide evaluation. The plantation was partially harvested in 1976 and 1977. Pretreatment weevil populations were noted (on April 17) by inspecting for adults in the duff, on stumps, under trunk end pieces left from harvest and old pupation chambers. A few weevils were active and ovipositing. A tree row with at least 7 new stumps (under 1 year old) was treated as one replicate/treatment. Treatments were replicated 4 times in a randomized complete block design. Each stump received 4-6 02 spray consisting of insecticide in kerosene (except Penncap-M in water) applied with a compression sprayer April 17. Temperature was 8°-10°C with wind 2 mph. The stumps were inspected (5 each of 4 rep) on Oct. 30 for chip cocoons following removal of bark to the first lateral root. Weevil cocoons were not differentiated as to species.

Adenovirus DNA: IV. Topology of Adenovirus Genomes

End fragments of molecular weight 1 to 2.5 × 10 6 were prepared from the DNA molecules of human adenovirus 2 and simian adenovirus SA-7. These end pieces were shown by DNA-DNA hybridization to contain only 15 to 30% of the sequences present in the entire genome. These data eliminate the possibility that adenovirus DNA molecules are circularly permuted.

Construction and operation of a Weber-type gravitational-wave detector and of a divided-bar prototype

In this let ter we describe some relevant characteristics of a Weber-type detector and the observation of its thermal noise. Fo r comparison we also report briefly on the operation of a divided-bar prototype. We have decided to repeat Wcber 's experiment (1) not only to check his results, but because so far, it seems to be the most sensitive device for detecting gravitat ional waves. In addition, this will provide us with a longer baseline for coincidence meas. urements. The cylinder material, cylinder dimensions and the piezoelectric ceramic transducers are those used by W:EB~R. The cylinder is suspended by a steel wire in a vacuo of about 5.10 -4 Torr. Some tests showed tha t the shape of the antenna or a deep groove for the suspension wire, have no influence on the quali ty factor Q. t towever, a large area of contact between the wire and the cylinder will reduce the Q drastically. For example, with a 5 mm ZI wire in a groove of the same curvature and 1.2 mm deep a Q of 390000 was measured. With a 3 .9mm ~ wire in the same groove the Q was 570000. For safety reasons we chose the 5 mm Z~ wire and the groove was made only 0.2 mm deep. The Q was then 540000. The mechanical isolation of the antenna was obtained by acoustical filters (steel blocks and silicone rubber) and springs inside the tank and felt layers between concrete blocks under the tank. This isolation system could be great ly improved by increasing the length of the suspension wire so tha t its free par t was ~ 60 cm on each side. The transducers glued on the cylinder are 4 piczoeeramic square plates 5 • 5 • 1.2 cm (clevite, lead zirconate t i tanate IIDT31), surface ground to fit the curvature of the cylinder. Some tests were made with 3 types of glue: Kodak 910, E-SOLDER-3021 (a silver conductive epoxy) and Torr Seal. We found the coupling to be almost equal for these glues, blur the dissipation of Torr Seal and silver epoxy is less than that of Kodak 910. End pieces were used to increase the coupling. In Fig. 1 some of the examined end-piece configurations are shown (the tests were made in two steps, first gluing the

UNUSUAL PEROXIDASE-POSITIVE GRANULES IN THE DEVELOPING RAT SUBMAXILLARY GLAND

Unusual peroxidase-positive granules exist in a particular cell type in the rat submaxillary gland during the first 2 wk after birth . The granules display remarkable substructure and clearly show cytochemical evidence of endogenous peroxidase activity . The cells containing the peroxidase-positive granules comprise portions of the end pieces, or so-called terminal (4), in the developing submaxillary gland. (The tubules are transient structures that eventually will give rise to mature acini [4]) . Along with the cells containing the peroxidasepositive granules, another cell type also exists in the tubules at birth . It contains homogeneous granules which do not stain for peroxidase . It is not until about the fifth day after birth that a third, acinar type cell, is seen . The purpose of this preliminary report is to focus upon a description of the unusual peroxidase-positive granules as they are seen at different stages of submaxillary gland development .

Elastic Constants of Compression-Annealed Pyrolytic Graphite

The elastic constants of pyrolytic graphite which has been highly ordered by annealing under compressive stress have been determined by ultrasonic, sonic resonance, and static test methods. Ultrasonic tests yielded the elastic constants c11, c12, c33, c44 = 1/s44, and the stress derivative of c33. The moduli 1/s11 and c44 were determined from the free flexural resonant vibrations of bars, and the shear modulus c44 also was determined from the fundamental torsional resonance of the bars and from the resonance of compound torsion oscillators composed of thin graphite disks with steel end pieces. Static tension, compression, and torsion tests on the pyrolytic graphite yielded a complete set of compliances (s11, s12, s13, s33, and s44). The following self-consistent set of elastic constants (cij in units of 1011 dyn/cm2; sij in 10−11 cm2/dyn) has been deduced from the results: c11 = 106±2, c12 = 18±2, c33 = 3.65±0.10, c13 = 1.5±0.5, c44 = 0.018 to 0.035, 1/s11 = 102±3, 1/s33 = 3.65±0.10, s12 = −0.0016±0.0006, s13 = −0.0033±0.0008, and s66 = 0.023±0.002; with the possible exception of c44, these constants are expected to be typical of the graphite single crystal. The shear strength for shear between basal planes was found to be in the range of 90–250 g/mm2.