Physiological asymmetry in etiolated pea epicotyls: relation to patterns of auxin distribution and phototropic behavior.

PubMed

Kuhn, H; Galston, A W

1992-01-01

Etiolated pea seedlings require transformation of Pr phytochrome to Pfr before they display optimal phototropic response to unilateral blue light. This study investigates the possible role of auxin transport in explaining these phenomena. Labeled [2-14C]IAA applied to the intact terminal buds of dark-grown and red light-treated pea seedlings was measured 210 min later on the shaded and illuminated sides of the epicotyl as a function of direction and duration of irradiation with blue light. Totally darkened epicotyls show an asymmetry in distribution of radioactivity in the upper growth zone of the epicotyl, in favor of the side under the concave part of the apical hook. Red light, which greatly potentiates curvature toward subsequent unilateral blue light, lowers this asymmetry. Blue light directed to the epicotyl of red-pretreated plants in a plane parallel to the hook and from the side bearing the convex portion of the hook induces positive phototropic curvature as well as a surplus of radioactivity on the illuminated side of the upper epicotyl and on the shaded side of the lower growth zone of the epicotyl. Light directed to the side bearing the concave part of the hook also causes an accumulation of counts in the upper part of the lighted side but produces neither curvature of the epicotyl nor accumulation of counts in the lower shaded side. Because of this built-in physiological asymmetry in the growth zone just below the apical hook, it is difficult to explain the effects of red and blue light on curvature in terms of patterns of auxin distribution alone.

Comparative photoelastic study of dental and skeletal anchorages in the canine retraction.

PubMed

de Assis Claro, Cristiane Aparecida; Chagas, Rosana Villela; Neves, Ana Christina Elias Claro; da Silva-Concílio, Laís Regiane

2014-01-01

To compare dental and skeletal anchorages in mandibular canine retraction by means of a stress distribution analysis. A photoelastic model was produced from second molar to canine, without the first premolar, and mandibular canine retraction was simulated by a rubber band tied to two types of anchorage: dental anchorage, in the first molar attached to adjacent teeth, and skeletal anchorage with a hook simulating the mini-implant. The forces were applied 10 times and observed in a circular polariscope. The stresses located in the mandibular canine were recorded in 7 regions. The Mann-Whitney test was employed to compare the stress in each region and between both anchorage systems. The stresses in the mandibular canine periradicular regions were compared by the Kruskal-Wallis test. Stresses were similar in the cervical region and the middle third. In the apical third, the stresses associated with skeletal anchorage were higher than the stresses associated with dental anchorage. The results of the Kruskal-Wallis test showed that the highest stresses were identified in the cervical-distal, apical-distal, and apex regions with the use of dental anchorage; and in the apical-distal, apical-mesial, cervical-distal, and apex regions with the use of skeletal anchorage. The use of skeletal anchorage in canine retraction caused greater stress in the apical third than the use of dental anchorage, which indicates an intrusive component resulting from the direction of the force due to the position of the mini-implant and the bracket hook of the canine.

Physiology of Movements in the Stems of Seedling Pisum sativum L. cv Alaska 1

PubMed Central

Britz, Steven J.; Galston, Arthur W.

1983-01-01

Phototropic response in etiolated pea (Pisum sativum L. cv Alaska) seedlings is poor. However, the curvature induced by unilateral blue light can be hastened and increased in magnitude by a previously administered red light pulse followed by several hours of darkness. Phytochrome is involved in the red light effect. Phototropic response was almost completely inhibited by removal of the apical bud and hook, but it was restored if exogenous indole-3-acetic acid was applied apically to the cut stump. Therefore, the stem contains both the phototropic photoreceptor and response mechanism. Perception of gravity and gravitropic response were also localized in the stem, but gravitropism was scarcely inhibited by decapitation. It was also observed that the kinetics and curvature pattern of gravitropism differed greatly from those of phototropism. Like phototropism, stem nutation required auxin and was promoted by red light. Unlike phototropism, photoenhanced nutational curvature required the apical hook and was propagated as a wave down the stem. Naphthylphthalamic acid inhibited, in order of decreasing effect, nutation, phototropism/gravitropism, and growth. Phototropism, gravitropism, and nutation appear to represent distinct forms of stem movement with fundamental differences in the mechanisms of curvature development. Images Fig. 3 PMID:16662824

Comparative photoelastic study of dental and skeletal anchorages in the canine retraction

PubMed Central

Claro, Cristiane Aparecida de Assis; Chagas, Rosana Villela; Neves, Ana Christina Elias Claro; da Silva-Concílio, Laís Regiane

2014-01-01

Objective To compare dental and skeletal anchorages in mandibular canine retraction by means of a stress distribution analysis. Methods A photoelastic model was produced from second molar to canine, without the first premolar, and mandibular canine retraction was simulated by a rubber band tied to two types of anchorage: dental anchorage, in the first molar attached to adjacent teeth, and skeletal anchorage with a hook simulating the mini-implant. The forces were applied 10 times and observed in a circular polariscope. The stresses located in the mandibular canine were recorded in 7 regions. The Mann-Whitney test was employed to compare the stress in each region and between both anchorage systems. The stresses in the mandibular canine periradicular regions were compared by the Kruskal-Wallis test. Results Stresses were similar in the cervical region and the middle third. In the apical third, the stresses associated with skeletal anchorage were higher than the stresses associated with dental anchorage. The results of the Kruskal-Wallis test showed that the highest stresses were identified in the cervical-distal, apical-distal, and apex regions with the use of dental anchorage, and in the apical-distal, apical-mesial, cervical-distal, and apex regions with the use of skeletal anchorage. Conclusions The use of skeletal anchorage in canine retraction caused greater stress in the apical third than the use of dental anchorage, which indicates an intrusive component resulting from the direction of the force due to the position of the mini-implant and the bracket hook of the canine. PMID:24713566

Phototropin 1 and dim-blue light modulate the red light de-etiolation response.

PubMed

Wang, Yihai; M Folta, Kevin

2014-01-01

Light signals regulate seedling morphological changes during de-etiolation through the coordinated actions of multiple light-sensing pathways. Previously we have shown that red-light-induced hypocotyl growth inhibition can be reversed by addition of dim blue light through the action of phototropin 1 (phot1). Here we further examine the fluence-rate relationships of this blue light effect in short-term (hours) and long-term (days) hypocotyl growth assays. The red stem-growth inhibition and blue promotion is a low-fluence rate response, and blue light delays or attenuates both the red light and far-red light responses. These de-etiolation responses include blue light reversal of red or far-red induced apical hook opening. This response also requires phot1. Cryptochromes (cry1 and cry2) are activated by higher blue light fluence-rates and override phot1's influence on hypocotyl growth promotion. Exogenous application of auxin transport inhibitor naphthylphthalamic acid abolished the blue light stem growth promotion in both hypocotyl growth and hook opening. Results from the genetic tests of this blue light effect in auxin transporter mutants, as well as phytochrome kinase substrate mutants indicated that aux1 may play a role in blue light reversal of red light response. Together, the phot1-mediated adjustment of phytochrome-regulated photomorphogenic events is most robust in dim blue light conditions and is likely modulated by auxin transport through its transporters.

Strategies of seedlings to overcome their sessile nature: auxin in mobility control.

PubMed

Žádníková, Petra; Smet, Dajo; Zhu, Qiang; Van Der Straeten, Dominique; Benková, Eva

2015-01-01

Plants are sessile organisms that are permanently restricted to their site of germination. To compensate for their lack of mobility, plants evolved unique mechanisms enabling them to rapidly react to ever changing environmental conditions and flexibly adapt their postembryonic developmental program. A prominent demonstration of this developmental plasticity is their ability to bend organs in order to reach the position most optimal for growth and utilization of light, nutrients, and other resources. Shortly after germination, dicotyledonous seedlings form a bended structure, the so-called apical hook, to protect the delicate shoot meristem and cotyledons from damage when penetrating through the soil. Upon perception of a light stimulus, the apical hook rapidly opens and the photomorphogenic developmental program is activated. After germination, plant organs are able to align their growth with the light source and adopt the most favorable orientation through bending, in a process named phototropism. On the other hand, when roots and shoots are diverted from their upright orientation, they immediately detect a change in the gravity vector and bend to maintain a vertical growth direction. Noteworthy, despite the diversity of external stimuli perceived by different plant organs, all plant tropic movements share a common mechanistic basis: differential cell growth. In our review, we will discuss the molecular principles underlying various tropic responses with the focus on mechanisms mediating the perception of external signals, transduction cascades and downstream responses that regulate differential cell growth and consequently, organ bending. In particular, we highlight common and specific features of regulatory pathways in control of the bending of organs and a role for the plant hormone auxin as a key regulatory component.

Strategies of seedlings to overcome their sessile nature: auxin in mobility control

PubMed Central

Žádníková, Petra; Smet, Dajo; Zhu, Qiang; Straeten, Dominique Van Der; Benková, Eva

2015-01-01

Plants are sessile organisms that are permanently restricted to their site of germination. To compensate for their lack of mobility, plants evolved unique mechanisms enabling them to rapidly react to ever changing environmental conditions and flexibly adapt their postembryonic developmental program. A prominent demonstration of this developmental plasticity is their ability to bend organs in order to reach the position most optimal for growth and utilization of light, nutrients, and other resources. Shortly after germination, dicotyledonous seedlings form a bended structure, the so-called apical hook, to protect the delicate shoot meristem and cotyledons from damage when penetrating through the soil. Upon perception of a light stimulus, the apical hook rapidly opens and the photomorphogenic developmental program is activated. After germination, plant organs are able to align their growth with the light source and adopt the most favorable orientation through bending, in a process named phototropism. On the other hand, when roots and shoots are diverted from their upright orientation, they immediately detect a change in the gravity vector and bend to maintain a vertical growth direction. Noteworthy, despite the diversity of external stimuli perceived by different plant organs, all plant tropic movements share a common mechanistic basis: differential cell growth. In our review, we will discuss the molecular principles underlying various tropic responses with the focus on mechanisms mediating the perception of external signals, transduction cascades and downstream responses that regulate differential cell growth and consequently, organ bending. In particular, we highlight common and specific features of regulatory pathways in control of the bending of organs and a role for the plant hormone auxin as a key regulatory component. PMID:25926839

Jasmonic acid protects etiolated seedlings of Arabidopsis thaliana against herbivorous arthropods

PubMed Central

Boex-Fontvieille, Edouard; Rustgi, Sachin; Von Wettstein, Diter; Pollmann, Stephan; Reinbothe, Steffen; Reinbothe, Christiane

2016-01-01

ABSTRACT Seed predators can cause mass ingestion of larger seed populations. As well, herbivorous arthropods attempt to attack etiolated seedlings and chose the apical hook for ingestion, aimed at dropping the cotyledons for later consumption. Etiolated seedlings, as we show here, have established an efficient mechanism of protecting their Achilles' heel against these predators, however. Evidence is provided for a role of jasmonic acid (JA) in this largely uncharacterized plant-herbivore interaction during skotomorphogenesis and that this comprises the temporally and spatially tightly controlled synthesis of a cysteine protease inhibitors of the Kunitz family. Interestingly, the same Kunitz protease inhibitor was found to be expressed in flowers of Arabidopsis where endogenous JA levels are high for fertility. Because both the apical hook and inflorescences were preferred isopod targets in JA-deficient plants that could be rescued by exogenously administered JA, our data identify a JA-dependent mechanism of plant arthropod deterrence that is recalled in different organs and at quite different times of plant development. PMID:27485473

Phototropin 1 and dim-blue light modulate the red light de-etiolation response

PubMed Central

Wang, Yihai; M Folta, Kevin

2014-01-01

Light signals regulate seedling morphological changes during de-etiolation through the coordinated actions of multiple light-sensing pathways. Previously we have shown that red-light-induced hypocotyl growth inhibition can be reversed by addition of dim blue light through the action of phototropin 1 (phot1). Here we further examine the fluence-rate relationships of this blue light effect in short-term (hours) and long-term (days) hypocotyl growth assays. The red stem-growth inhibition and blue promotion is a low-fluence rate response, and blue light delays or attenuates both the red light and far-red light responses. These de-etiolation responses include blue light reversal of red or far-red induced apical hook opening. This response also requires phot1. Cryptochromes (cry1 and cry2) are activated by higher blue light fluence-rates and override phot1's influence on hypocotyl growth promotion. Exogenous application of auxin transport inhibitor naphthylphthalamic acid abolished the blue light stem growth promotion in both hypocotyl growth and hook opening. Results from the genetic tests of this blue light effect in auxin transporter mutants, as well as phytochrome kinase substrate mutants indicated that aux1 may play a role in blue light reversal of red light response. Together, the phot1-mediated adjustment of phytochrome-regulated photomorphogenic events is most robust in dim blue light conditions and is likely modulated by auxin transport through its transporters. PMID:25482790

Atactorhynchus duranguensis n. sp. (Acanthocephala: Atactorhynchinae) from Cyprinodon meeki (Pisces: Cyprinodontidae) near Durango, Mexico.

PubMed

Salgado-Maldonado, Guillermo; Aguilar-Aguilar, Rogelio; Cabañas-Carranza, Guillermina

2005-03-01

Atactorhynchus duranguensis n. sp. (Acanthocephala: Atactorhynchinae) is described from the intestine of Cyprinodon meeki Miller, an endemic freshwater fish from a far-inland locality of Mexico. Diagnostic features include: body small, stout, ventrally curved; small cylindrical proboscis armed with 16 alternating vertical rows of four or five hooks; anterior two or three hooks conspicuous, stout and larger than other hooks, and have large, rod-shaped roots with a markedly and abruptly enlarged base; three posterior hooks of each row are smaller and rootless; single-walled proboscis receptacle; lemnisci equal in length, elongate and robust; and cement gland syncytial, larger than testis. The new species is smaller than A. verecundus Chandler, 1935, the only previously described species in the genus. The shape of the proboscis of the new species is strikingly different from that of A. verecundus, which is widest at the apex. Likewise, the greatest width of the trunk of the new species is in about the middle, differing from that of A. verecundus where the trunk is widest posteriorly. The new species also can be distinguished from A. verecundus because of its much smaller hook lengths and slightly smaller proboscis. In addition, the proportion of large apical proboscis hooks in relation to the small basal hooks is different: the basal hooks of A. verecundus are about half the size of the anterior hooks and but only about a quarter of the size in A. duranguensis. Unlike A. verecundus, the base of the roots are markedly and abruptly enlarged in the new species. Finally, the eggs of the new species are smaller (23-27 x 8-10 microm) than those of A. verecundus (27-30 x 12-13 microm).

Comparative analysis of hook, hybrid, and pedicle screw instrumentation in the posterior treatment of adolescent idiopathic scoliosis.

PubMed

Yilmaz, Guney; Borkhuu, Battugs; Dhawale, Arjun A; Oto, Murat; Littleton, Aaron G; Mason, Dan E; Gabos, Peter G; Shah, Suken A

2012-01-01

Spinal instrumentation in adolescent idiopathic scoliosis (AIS) aims to correct spinal deformity and maintain long-term spinal stability until bony healing is ensured. The purpose of this study was to compare the minimum 2-year postoperative radiographic and clinical results of posterior spine correction and fusion with all-hook instrumentation versus hybrid segmental instrumentation versus pedicle screw instrumentation for AIS from a single institution. A total of 105 patients with AIS who underwent a posterior spinal fusion with segmental pedicle screw (35), hook (35), or hybrid (35) instrumentation were sorted and matched according to the following criteria: similar age at surgery, identical Lenke curve types, curve magnitude, and Risser grade. Patients were evaluated before, immediately after, and at 2 years after surgery for radiographic parameters, complications, and outcome, as well as on the basis of the Scoliosis Research Society (SRS) questionnaire. The age and Risser grade, major curve Cobb angle, apical vertebral rotation (AVR), apical vertebral translation (AVT), lowest instrumented vertebral tilt, global coronal and sagittal balance, lumbar lordosis, and thoracic kyphosis were determined as part of preoperative evaluation. All 3 groups showed significant differences between the preoperative and postoperative major curve Cobb angle, lowest instrumented vertebral tilt, AVT, and AVR. At the latest follow-up, lumbar lordosis, thoracic kyphosis, and global coronal and sagittal balance remained similar among the 3 groups. Major curve Cobb angle, AVT, and AVR were significantly different--the hook group's measurements were significantly higher than the other groups, but there was no difference between the pedicle screw and hybrid groups. Major curve correction rate was significantly different among all groups (screw=71.9%±13.8%, hybrid=61.4%±16.6%, hook=48.1%±19.7%) (P<0.001). The pedicle screw group had the least amount of correction loss but there was no statistically significant difference between groups (screw=2.6±6.7 degrees, hybrid=4.5±7.4 degrees, hook=4.4±6.2 degrees) (P=0.35). The hook group had the least amount of AVT correction, but the screw group and the hybrid groups were similar (pedicle=67.3%±15.5%, hybrid=57.5%±22.4%, hook=39.9%±32.5%) (P<0.001). Surgery time and blood loss were higher in the screw group. No differences in global SRS-22 scores were demonstrated between the patients treated with pedicle screw, hybrid, and hook constructs; however, the satisfaction domain was higher in the screw group at the latest follow-up. Pedicle screw and hybrid instrumentations offer significantly better spinal deformity correction than hook constructs in major curve coronal correction, AVT, and AVR. Patients with pedicle screw instrumentation had the greatest curve correction percentage, maintenance of this correction in the coronal and sagittal planes, and higher patient satisfaction by the SRS outcome scores. Global SRS-22 scores were similar at 2-year follow-up in all groups. Therapeutic level III retrospective comparative study.

An Ethylene-Protected Achilles’ Heel of Etiolated Seedlings for Arthropod Deterrence

PubMed Central

Boex-Fontvieille, Edouard; Rustgi, Sachin; von Wettstein, Diter; Pollmann, Stephan; Reinbothe, Steffen; Reinbothe, Christiane

2016-01-01

A small family of Kunitz protease inhibitors exists in Arabidopsis thaliana, a member of which (encoded by At1g72290) accomplishes highly specific roles during plant development. Arabidopsis Kunitz-protease inhibitor 1 (Kunitz-PI;1), as we dubbed this protein here, is operative as cysteine PI. Activity measurements revealed that despite the presence of the conserved Kunitz-motif the bacterially expressed Kunitz-PI;1 was unable to inhibit serine proteases such as trypsin and chymotrypsin, but very efficiently inhibited the cysteine protease RESPONSIVE TO DESICCATION 21. Western blotting and cytolocalization studies using mono-specific antibodies recalled Kunitz-PI;1 protein expression in flowers, young siliques and etiolated seedlings. In dark-grown seedlings, maximum Kunitz-PI;1 promoter activity was detected in the apical hook region and apical parts of the hypocotyls. Immunolocalization confirmed Kunitz-PI;1 expression in these organs and tissues. No transmitting tract (NTT) and HECATE 1 (HEC1), two transcription factors previously implicated in the formation of the female reproductive tract in flowers of Arabidopsis, were identified to regulate Kunitz-PI;1 expression in the dark and during greening, with NTT acting negatively and HEC1 acting positively. Laboratory feeding experiments with isopod crustaceans such as Porcellio scaber (woodlouse) and Armadillidium vulgare (pillbug) pinpointed the apical hook as ethylene-protected Achilles’ heel of etiolated seedlings. Because exogenous application of the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC) and mechanical stress (wounding) strongly up-regulated HEC1-dependent Kunitz-PI;1 gene expression, our results identify a new circuit controlling herbivore deterrence of etiolated plants in which Kunitz-PI;1 is involved. PMID:27625656

The RCN1-encoded A subunit of protein phosphatase 2A increases phosphatase activity in vivo

NASA Technical Reports Server (NTRS)

Deruere, J.; Jackson, K.; Garbers, C.; Soll, D.; Delong, A.; Evans, M. L. (Principal Investigator)

1999-01-01

Protein phosphatase 2A (PP2A), a heterotrimeric serine/threonine-specific protein phosphatase, comprises a catalytic C subunit and two distinct regulatory subunits, A and B. The RCN1 gene encodes one of three A regulatory subunits in Arabidopsis thaliana. A T-DNA insertion mutation at this locus impairs root curling, seedling organ elongation and apical hypocotyl hook formation. We have used in vivo and in vitro assays to gauge the impact of the rcn1 mutation on PP2A activity in seedlings. PP2A activity is decreased in extracts from rcn1 mutant seedlings, and this decrease is not due to a reduction in catalytic subunit expression. Roots of mutant seedlings exhibit increased sensitivity to the phosphatase inhibitors okadaic acid and cantharidin in organ elongation assays. Shoots of dark-grown, but not light-grown seedlings also show increased inhibitor sensitivity. Furthermore, cantharidin treatment of wild-type seedlings mimics the rcn1 defect in root curling, root waving and hypocotyl hook formation assays. In roots of wild-type seedlings, RCN1 mRNA is expressed at high levels in root tips, and accumulates to lower levels in the pericycle and lateral root primordia. In shoots, RCN1 is expressed in the apical hook and the basal, rapidly elongating cells in etiolated hypocotyls, and in the shoot meristem and leaf primordia of light-grown seedlings. Our results show that the wild-type RCN1-encoded A subunit functions as a positive regulator of the PP2A holoenzyme, increasing activity towards substrates involved in organ elongation and differential cell elongation responses such as root curling.

Clathrin-Mediated Auxin Efflux and Maxima Regulate Hypocotyl Hook Formation and Light-Stimulated Hook Opening in Arabidopsis.

PubMed

Yu, Qinqin; Zhang, Ying; Wang, Juan; Yan, Xu; Wang, Chao; Xu, Jian; Pan, Jianwei

2016-01-04

The establishment of auxin maxima by PIN-FORMED 3 (PIN3)- and AUXIN RESISTANT 1/LIKE AUX1 (LAX) 3 (AUX1/LAX3)-mediated auxin transport is essential for hook formation in Arabidopsis hypocotyls. Until now, however, the underlying regulatory mechanism has remained poorly understood. Here, we show that loss of function of clathrin light chain CLC2 and CLC3 genes enhanced auxin maxima and thereby hook curvature, alleviated the inhibitory effect of auxin overproduction on auxin maxima and hook curvature, and delayed blue light-stimulated auxin maxima reduction and hook opening. Moreover, pharmacological experiments revealed that auxin maxima formation and hook curvature in clc2 clc3 were sensitive to auxin efflux inhibitors 1-naphthylphthalamic acid and 2,3,5-triiodobenzoic acid but not to the auxin influx inhibitor 1-naphthoxyacetic acid. Live-cell imaging analysis further uncovered that loss of CLC2 and CLC3 function impaired PIN3 endocytosis and promoted its lateralization in the cortical cells but did not affect AUX1 localization. Taken together, these results suggest that clathrin regulates auxin maxima and thereby hook formation through modulating PIN3 localization and auxin efflux, providing a novel mechanism that integrates developmental signals and environmental cues to regulate plant skotomorphogenesis and photomorphogenesis. Copyright © 2016 The Author. Published by Elsevier Inc. All rights reserved.

29 CFR 1910.184 - Slings.

Code of Federal Regulations, 2013 CFR

2013-07-01

... under the load and has both ends, end attachments, eyes or handles on the hook or a single master link... lifting hook. Cable laid endless sling-mechanical joint is a wire rope sling made endless by joining the.... N-184-1.) Handle eye is an opening in a handle of a metal mesh sling shaped to accept a hook...

29 CFR 1910.184 - Slings.

Code of Federal Regulations, 2014 CFR

2014-07-01

... under the load and has both ends, end attachments, eyes or handles on the hook or a single master link... lifting hook. Cable laid endless sling-mechanical joint is a wire rope sling made endless by joining the.... N-184-1.) Handle eye is an opening in a handle of a metal mesh sling shaped to accept a hook...

29 CFR 1910.184 - Slings.

Code of Federal Regulations, 2012 CFR

2012-07-01

... under the load and has both ends, end attachments, eyes or handles on the hook or a single master link... lifting hook. Cable laid endless sling-mechanical joint is a wire rope sling made endless by joining the.... N-184-1.) Handle eye is an opening in a handle of a metal mesh sling shaped to accept a hook...

[Finite element analysis of mechanical characteristics during retracting mandibular incisors through sliding mechanics].

PubMed

Gu, Yong-Jia; Wu, Yan-Ping; Gao, Mei-Qin; Yao, Ning; Chen, Wen-Jing

2008-10-01

To analyze the mechanical characteristic changes of teeth and arch under different loading direction during retracting mandibular incisors through implant, simulating clinical loading system. Three- dimensional finite element model, including brackets, archwire, crampable hooks and implants, was reconstructed. The force direction was determined by connecting the points in crampable hook and the center point of implant, and the force point and force direction were changed with the adjustment of the height of crampable hook and the height of implant. Then three-dimensional movement trend of teeth, stress distribution in periodontal membrane and the largest displacement of archwire nodes in each group were calculated and analyzed. SPSS13.0 software package was used for statistical analysis. It was found that the height of implant and the height of crampable hook were correlated with the movement of teeth and stress distribution in periodontal membrane (P<0.01). The movement trend of teeth in the condition of different height of implant and different height of crampable hook was illustrated as follows:(1)with the height increase of crampable hook, the movement trend of the central and lateral incisors varied from mesial lingual tipping to mesial labial tipping. However, canines tipped distally and lingually; the second premolars tipped mesially and lingually, and the first molar roots tipped distally and buccally with decreasing tipping angle. (2) The largest stress distribution in the whole arch was located in the labial apical one-third area of the lateral incisors, while that of canines and the first molars was located in the alveolar ridges and root bifurcations. These findings indicate that the different movement trend during retracting anterior teeth can be achieved through the adjustment of the height of crampable hook, and implant, anchorage can effectively control anterior movement of the posterior teeth. Supported by Research Fund of Bureau of Science and Technology of Nantong City (Grant No. S40023).

Micro devices using shape memory polymer patches for mated connections

DOEpatents

Lee, Abraham P.; Fitch, Joseph P.

2000-01-01

A method and micro device for repositioning or retrieving miniature devices located in inaccessible areas, such as medical devices (e.g., stents, embolic coils, etc.) located in a blood vessel. The micro repositioning or retrieving device and method uses shape memory polymer (SMP) patches formed into mating geometries (e.g., a hoop and a hook) for re-attachment of the deposited medical device to a catheter or guidewire. For example, SMP or other material hoops are formed on the medical device to be deposited in a blood vessel, and SMP hooks are formed on the micro device attached to a guidewire, whereby the hooks on the micro device attach to the hoops on the medical device, or vice versa, enabling deposition, movement, re-deposit, or retrieval of the medical device. By changing the temperature of the SMP hooks, the hooks can be attached to or released from the hoops located on the medical device. An exemplary method for forming the hooks and hoops involves depositing a sacrificial thin film on a substrate, patterning and processing the thin film to form openings therethrough, depositing or bonding SMP materials in the openings so as to be attached to the substrate, and removing the sacrificial thin film.

Morphological and molecular data reveal a new species of Neoechinorhynchus (Acanthocephala: Neoechinorhynchidae) from Dormitator maculatus in the Gulf of Mexico.

PubMed

Pinacho-Pinacho, Carlos Daniel; Sereno-Uribe, Ana L; García-Varela, Martín

2014-12-01

Neoechinorhynchus (Neoechinorhynchus) mexicoensis sp. n. is described from the intestine of Dormitator maculatus (Bloch 1792) collected in 5 coastal localities from the Gulf of Mexico. The new species is mainly distinguished from the other 33 described species of Neoechinorhynchus from the Americas associated with freshwater, marine and brackish fishes by having smaller middle and posterior hooks and possessing a small proboscis with three rows of six hooks each, apical hooks longer than other hooks and extending to the same level as the posterior hooks, 1 giant nucleus in the ventral body wall and females with eggs longer than other congeneric species. Sequences of the internal transcribed spacer (ITS) and the large subunit (LSU) of ribosomal DNA including the domain D2+D3 were used independently to corroborate the morphological distinction among the new species and other congeneric species associated with freshwater and brackish water fish from Mexico. The genetic divergence estimated among congeneric species ranged from 7.34 to 44% for ITS and from 1.65 to 32.9% for LSU. Maximum likelihood and Bayesian inference analyses with each dataset showed that the 25 specimens analyzed from 5 localities of the coast of the Gulf of Mexico parasitizing D. maculatus represent an independent clade with strong bootstrap support and posterior probabilities. The morphological evidence, plus the monophyly in the phylogenetic analyses, indicates that the acanthocephalans collected from intestine of D. maculatus from the Gulf of Mexico represent a new species, herein named N. (N.) mexicoensis sp. n. Copyright © 2014. Published by Elsevier Ireland Ltd.

Calcium-enriched mixture cement as artificial apical barrier: A case series

PubMed Central

Nosrat, Ali; Asgary, Saeed; Eghbal, Mohammad Jafar; Ghoddusi, Jamileh; Bayat-Movahed, Saeed

2011-01-01

In comparison to the conventional apexification using calcium hydroxide, artificial apical barrier technique is more valuable and less time consuming. This article describes successful use of calcium-enriched mixture (CEM) cement as an artificial apical barrier in open apices. In this study, 13 single-rooted teeth with necrotic pulps and open apices were treated non-surgically. After copious irrigation of the root canals with NaOCl 5.25% and gentle filing, based on need for interappointment dressing, treatments were followed by CEM cement (BioniqueDent, Tehran, Iran) apical plug insertion in the first or second appointment. All cases were then permanently restored. All subjects were followed until radiographic evidence of periradicular healing was seen (mean 14.5 months). Clinically, all cases were functional and asymptomatic and complete osseous healing was observed in all the teeth. Considering the biological properties of CEM cement, this new endodontic biomaterial might be appropriate to be used as artificial apical barrier in the open apex teeth. PMID:22144818

Gateway National Recreation Area - Sandy Hook Unit : parking management study

DOT National Transportation Integrated Search

2003-12-01

This report describes the Parking Management System (PMS) concept for the Sandy Hook Traveler Information System (TIS). The PMS is an important component of the TIS because it ultimately will be used to determine the open / closed status of the park....

Entrapment of metal clusters in metal-organic framework channels by extended hooks anchored at open metal sites.

PubMed

Zheng, Shou-Tian; Zhao, Xiang; Lau, Samuel; Fuhr, Addis; Feng, Pingyun; Bu, Xianhui

2013-07-17

Reported here are the new concept of utilizing open metal sites (OMSs) for architectural pore design and its practical implementation. Specifically, it is shown here that OMSs can be used to run extended hooks (isonicotinates in this work) from the framework walls to the channel centers to effect the capture of single metal ions or clusters, with the concurrent partitioning of the large channel spaces into multiple domains, alteration of the host-guest charge relationship and associated guest-exchange properties, and transfer of OMSs from the walls to the channel centers. The concept of the extended hook, demonstrated here in the multicomponent dual-metal and dual-ligand system, should be generally applicable to a range of framework types.

Hybrid constructs for tridimensional correction of the thoracic spine in adolescent idiopathic scoliosis: a comparative analysis of universal clamps versus hooks.

PubMed

Ilharreborde, Brice; Even, Julien; Lefevre, Yan; Fitoussi, Franck; Presedo, Ana; Penneçot, Georges-François; Mazda, Keyvan

2010-02-01

Retrospective study of prospectively collected data. Compare Universal Clamps (UCs) and hooks for the thoracic correction of adolescent idiopathic scoliosis (AIS). In scoliosis surgery, sagittal correction is as important as frontal correction due to the risk of junctional kyphosis. Compared to all-screw constructs, hybrid constructs with lumbar pedicle screws and thoracic hooks or sublaminar wires have been shown to achieve similar coronal correction while providing superior postoperative thoracic kyphosis. The authors used a novel sublaminar thoracic implant, the UC with improvements over sublaminar wires. Hybrid constructs using thoracic UCs were compared to those with thoracic hooks. This series involved 150 patients treated for AIS with hybrid constructs. A total of 75 consecutive patients operated from 2001 to 2003, who had thoracic hooks with in situ contouring, distraction, and compression (Group 1), were compared to 75 consecutive patients operated from 2004 to 2006, who had thoracic UCs with posteromedial translation (Group 2). All had intraoperative somatosensory/motor-evoked potential monitoring and at least 2-years follow-up. Except for follow-up (longer in Group 1), the 2 groups were similar before surgery. The UCs achieved better thoracic coronal correction (P < 0.001), Cincinnati index (P < 0.001), kyphosis (P = 0.02), and apical rotation (P < 0.001). In normokyphotic or hypokyphotic patients, the UC corrected thoracic kyphosis by 11.2 degrees (55%) versus 0.4 degrees (2%) achieved by hooks (P < 0.0001). These differences were stable at last follow-up. There were no intraoperative complications or changes in somatosensory/motor-evoked potentials. UC reduced operative time by 20% (60 minutes; P < 0.001) and blood loss by 23% (250 mL; P < 0.001). Although both of these hybrid constructs efficaciously corrected the coronal and axial deformities in AIS, the results of the UC technique were superior to those achieved with hooks in all 3 planes, especially the sagittal plane. Moreover, the UC technique is straightforward and safe, reducing both operative duration and blood loss.

Turbine inner shroud and turbine assembly containing such inner shroud

DOEpatents

Bagepalli, Bharat Sampathkumaran; Corman, Gregory Scot; Dean, Anthony John; DiMascio, Paul Stephen; Mirdamadi, Massoud

2001-01-01

A turbine inner shroud and a turbine assembly. The turbine assembly includes a turbine stator having a longitudinal axis and having an outer shroud block with opposing and longitudinally outward facing first and second sides having open slots. A ceramic inner shroud has longitudinally inward facing hook portions which can longitudinally and radially surround a portion of the sides of the outer shroud block. In one attachment, the hook portions are engageable with, and are positioned within, the open slots.

SEM observations of resected root canal ends following apicoectomy.

PubMed

Furusawa, Masahiro; Asai, Yasuhiro

2002-02-01

The purpose of this study was to examine the apical foramen of root apices extracted during apicotomies. A total of 25 teeth extracted from 25 patients admitted to the Department of Conservative Dentistry at Tokyo Dental College's Chiba Hospital were used for the study. All patients were between 22 to 56 years of age at the time of the study, and each of the 25 cases was determined clinically on radiographs to be chronic apical suppurative periodontitis. Microsurgery was performed on all cases, and the extracted root apices were then observed using SEM. The results demonstrated a wide opening, greater than 350 microns as measured along the major axis, of the apical foramen in 80% of the cases. Various characteristics indicative of resorption were observed around the apical foramen. These features included those believed to have been caused by overinstrumentation during root canal treatment as well as irregularly shaped areas presumed to be apical lesions that had enlarged and eroded. We observed a high frequency of manifestations of cementum resorption surrounding the root apices of teeth with apical lesions. Furthermore, we concluded that in the majority of cases in the present study, due to the fact that the apical foramen exceeded normal opening dimensions as a result of overinstrumentation during root canal treatment or resorption around the root apex, prolongation of the lesions had occurred in response to direct contact of microbial infectious matter and tissues surrounding the root apex over a large area. The above finding suggested that, in cases in which the apical foramen is destroyed through overinstrumentation larger than #35 or in which the apical foramen opens up to dimensions greater than 350 microns due to pathologic resorption, surgical intervention may be indicated. On the other hand, in 64% of the cases, an accessory canal was observed in the root apical lesion. Based on this observation, the presence of an accessory canal in the root apex may contribute to some degree to the prolongation of the lesion.

Use of calcium-containing endodontic sealers as apical barrier in fluid-contaminated wide-open apices.

PubMed

Prati, Carlo; Siboni, Francesco; Polimeni, Antonella; Bossu, Maurizio; Gandolfi, Maria Giovanna

2014-12-30

The sealing of wide-open apex roots is still a challenge and requires the use of apical barrier techniques. The aim was to evaluate ex vivo the sealing and the apical morphology of 3 commercial calcium oxide (CaO)-containing sealers - namely, 2 zinc oxide-based (CRCS and Sealapex) and a calcium silicate MTA-based (TechBiosealer Endo) - placed in wet root canals with artificial wide-open apices.
 Thirty human single-rooted teeth were shaped with Protaper and an artificial open apex (diameter size 110) was created. Each root was inserted in a custom-designed support containing simulated body fluid (Hank's balanced salt solution, HBSS) at the bottom simulating the presence of periapical fluid in the canal. Each sealer (TechBiosealer Endo, CRCS, Sealapex) was compacted to the apical 5 mm and the filled roots stored in HBSS at 37°C. The sealing was evaluated as microinfiltrated fluid since 24 hours up to 6 months using a high-precision digital fluid flow meter. The sealers were also studied for setting time in HBSS, calcium releasing (statistical analysis by 2-way ANOVA followed by Student-Newman-Keuls test, P<0.05) and surface morpho-chemistry by ESEM-EDX and OM analysis.
 All sealers showed a stable seal. TechBiosealer Endo maintained a better seal than the other materials (P<0.05) and ESEM-EDX and OM analyses showed the presence of apatite deposits.
 The clinical use of hydraulic hydrophilic MTA-based sealers can be recommended to stop/reduce the fluid flow rate through the apex. The artificial apical barrier in wet wide apices is a suitable technique able to seal wet root canals.

Combustor liner construction

NASA Technical Reports Server (NTRS)

Craig, H. M.; Wagner, W. B.; Strock, W. J. (Inventor)

1983-01-01

A combustor liner is fabricated from a plurality of individual segments each containing counter/parallel Finwall material and are arranged circumferentially and axially to define the combustion zone. Each segment is supported by a hook and ring construction to an opened lattice frame with sufficient tolerance between the hook and ring to permit thermal expansion with a minimum of induced stresses.

TR-DB: an open-access database of compounds affecting the ethylene-induced triple response in Arabidopsis.

PubMed

Hu, Yuming; Callebert, Pieter; Vandemoortel, Ilse; Nguyen, Long; Audenaert, Dominique; Verschraegen, Luc; Vandenbussche, Filip; Van Der Straeten, Dominique

2014-02-01

Small molecules which act as hormone agonists or antagonists represent useful tools in fundamental research and are widely applied in agriculture to control hormone effects. High-throughput screening of large chemical compound libraries has yielded new findings in plant biology, with possible future applications in agriculture and horticulture. To further understand ethylene biosynthesis/signaling and its crosstalk with other hormones, we screened a 12,000 compound chemical library based on an ethylene-related bioassay of dark-grown Arabidopsis thaliana (L.) Heynh. seedlings. From the initial screening, 1313 (∼11%) biologically active small molecules altering the phenotype triggered by the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC), were identified. Selection and sorting in classes were based on the angle of curvature of the apical hook, the length and width of the hypocotyl and the root. A MySQL-database was constructed (https://chaos.ugent.be/WE15/) including basic chemical information on the compounds, images illustrating the phenotypes, phenotype descriptions and classification. The research perspectives for different classes of hit compounds will be evaluated, and some general screening tips for customized high-throughput screening and pitfalls will be discussed. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

A new genus and species of proteocephalidean tapeworm (Cestoda) from Pangasius larnaudii (Siluriformes: Pangasiidae) in Southeast Asia.

PubMed

Scholz, Tomáš; de Chambrier, Alain

2012-06-01

A new proteocephalidean cestode is described from spot pangasius, Pangasius larnaudii (Siluriformes: Pangasiidae), from Tonle Sap Lake in Cambodia and a new genus, Pangasiocestus , is proposed to accommodate it. The genus is placed in the Gangesiinae because its scolex possesses a large rostellum-like apical organ and its genital organs (testes, ovary, vitellarium, and uterus) are situated in the medulla, with some vitelline follicles paramuscular. Pangasiocestus romani n. gen. and n. sp., the type and only species of the new genus, is characterized mainly by its rosette-like scolex composed of 4 lobes bearing a small sucker in their center, and the apical part with a large, discoidal, rostellum-like apical organ devoid of hooks, by weakly developed inner longitudinal musculature formed by very few isolated muscle fibers, uneven size of testes in immature and mature proglottids, with lateral testes smaller and more dense than median ones, by very narrow lateral bands of vitelline follicles, formed usually by single follicles, and by the vagina anterior to the cirrus sac. This is the first proteocephalidean cestode from a pangasiid catfish identified to the species level (proteocephalidean cestodes from 3 Pangasius spp. reported in an unpublished account from Vietnam, misidentified as Proteocephalus osculatus (Goeze, 1782) [ =  Glanitaenia osculata ], are not considered).

Diphyllidean cestodes of the Gulf of California, México with descriptions of two new species of Echinobothrium (Cestoda: Diphyllidea).

PubMed

Tyler, G A

2001-02-01

As part of a survey of parasites of elasmobranchs in the Gulf of California, a second and final report of the diphyllidean cestodes resulting from the survey is presented. Of 43 species of elasmobranchs examined for parasites, 7 (Rhinobatos productus, Rhinobatos leucorhynchus, Myliobatis californicus, Myliobatis longirostris, Urobatis halleri, Urobatis maculatus, and Rhinoptera steindachneri) were found to host diphyllidean cestodes, all belonging to Echinobothrium. No species of either of the other 2 diphyllidean genera, Dirrachybothridium or Macrobothridium, were discovered. A greater diversity of diphyllideans was found in 1996 than in 1993. Two new species, Echinobothrium hoffmanorum n. sp. and Echinobothrium rayallemangi n. sp. are described from the spiral intestines of U. maculatus and R. leucorhynchus, respectively. Echinobothrium hoffmanorum is unique in its possession of the following combination of characters: 19-21 apical hooks in each dorsoventral group, 12-22 lateral hooklets in each group, 10-17 cephalic peduncle spines per column, 4-8 testes, 4-10 segments and eggs with a single filament. Echinobothrium rayallemangi is unique in its possession of the following combination of characters: 23 apical hooks in each dorsoventral group, 20-23 lateral hooklets in each group, 2-5 cephalic peduncle spines per column, 4-6 testes, and 4-6 segments. These 2 new species, together with Echinobothrium mexicanum and Echinobothrium fautleyae, brings the total number of diphyllideans known from the Gulf of California to 4. The survey of diphyllidean cestodes of the Gulf of California has resulted in a new host record for Echinobothrium for each of the host species mentioned above, with Rhinobatos and Urobatis representing new host genera and Urolophidae a new host family for Echinobothrium.

Extender for securing a closure

DOEpatents

Thomas, II, Patrick A.

2012-10-02

An apparatus for securing a closure such as door or a window that opens and closes by movement relative to a fixed structure such as a wall or a floor. Many embodiments provide a device for relocating a padlock from its normal location where it secures a fastener (such as a hasp) to a location for the padlock that is more accessible for locking and unlocking the padlock. Typically an extender is provided, where the extender has a hook at a first end that is disposed through the eye of the staple of the hasp, and at an opposing second end the extender has an annulus, such as a hole in the extender or a loop or ring affixed to the extender. The shackle of the padlock may be disposed through the annulus and may be disposed through the eye of a second staple to secure the door or window in a closed or open position. Some embodiments employ a rigid sheath to enclose at least a portion of the extender. Typically the rigid sheath has an open state where the hook is exposed outside the sheath and a closed state where the hook is disposed within the sheath.

77 FR 55735 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod in the Bering Sea and Aleutian...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-11

... closure. SUMMARY: NMFS is opening directed fishing for Pacific cod by catcher vessels less than 60 feet... Pacific cod allocated to catcher vessels less than 60 feet LOA using hook-and-line or pot gear in the BSAI... vessels less than 60 feet LOA using hook-and-line or pot gear in the BSAI under Sec. 679.20(d)(1)(iii) on...

76 FR 24404 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod in the Bering Sea and Aleutian...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-02

... closure. SUMMARY: NMFS is opening directed fishing for Pacific cod by catcher vessels less than 60 feet... Pacific cod allocated to catcher vessels less than 60 feet LOA using hook-and-line or pot gear in the BSAI... less than 60 feet LOA using hook-and-line or pot gear in the BSAI under Sec. 679.20(d)(1)(iii) on March...

Comparative evaluation of different forms of calcium hydroxide in apexification.

PubMed

Ghosh, Subhankar; Mazumdar, Dibyendu; Ray, Pradip Kumar; Bhattacharya, Bhaswar

2014-01-01

One out of every two children sustains a dental injury most often between 8 and 10 years of age. Majority of these teeth subsequently become non-vital and most often with immature apex. Management of these teeth is an enormous challenge for lack of apical stop. Calcium hydroxide in various formulations has maximum literature support in favor of successful apexification or induced apical closure. The aim of the following study is to determine the efficacy of calcium hydroxide in a different formulation to induce apexification. The present study was undertaken on 51 children of 8-10 years of age (both sexes) at Dr. R Ahmed Dental College and Hospital from April 2006 to March 2007. All children had one or two maxillary permanent central incisor (s), non-vital and apices open. In all the cases, apexification was attempted with either calcium hydroxide mixed with sterile distilled water, or calcium hydroxide plus iodoform in methyl cellulose base, or calcium hydroxide plus iodoform in polysilicone oil base. The success of apexification was determined on the basis of clinical and radiographic criteria. In the pre-operative asymptomatic cases (72.55%), failure occurred in only 5.45% cases and pre-operative symptomatic cases failure rate was as high as 35.71%. Success rate was 94.6% in cases with narrow open apices, whereas 64.28% in wide open apices. In cases with pre-existing apical radiolucencies, successful apexification occurred in 63.63% and success rate was 92.5% in the cases without pre-existing apical radiolucencies. Average time consumed for apexification was minimum with calcium hydroxide plus iodoform in polysilicone oil base. The overall success rate observed to be 86.27%, which is in close proximity to the findings of most of the previous studies across the globe.

Two fault tolerant toggle-hook release

NASA Technical Reports Server (NTRS)

Graves, Thomas Joseph (Inventor); Brown, Christopher William (Inventor)

1991-01-01

A coupling device is disclosed which is mechanically two fault tolerant for release. The device comprises a fastener plate and fastener body, each of which is attachable to a different one of a pair of structures to be joined. The fastener plate and body are coupled by an elongate toggle mounted at one end in a socket on the fastener plate for universal pivotal movement thereon. The other end of the toggle is received in an opening in the fastener body and adapted for limited pivotal movement therein. The toggle is adapted to be restrained by three latch hooks arranged in symmetrical equiangular spacing about the axis of the toggle, each hook being mounted on the fastener body for pivotal movement between an unlatching non-contact position with respect to the toggle and a latching position in engagement with a latching surface of the toggle. The device includes releasable lock means for locking each latch hook in its latching position whereby the toggle couples the fastener plate to the fastener body and means for releasing the lock means to unlock each said latch hook from the latch position whereby the unlocking of at least one of the latch hooks from its latching position results in the decoupling of the fastener plate from the fastener body.

Effects of hook plate on shoulder function after treatment of acromioclavicular joint dislocation.

PubMed

Chen, Chang-Hong; Dong, Qi-Rong; Zhou, Rong-Kui; Zhen, Hua-Qing; Jiao, Ya-Jun

2014-01-01

Internal fixation with hook plate has been used to treat acromioclavicular joint dislocation. This study aims to evaluate the effect of its use on shoulder function, to further analyze the contributing factors, and provide a basis for selection and design of improved internal fixation treatment of the acromioclavicular joint dislocation in the future. A retrospective analysis was performed on patients treated with a hook plate for acromioclavicular joint dislocation in our hospital from January 2010 to February 2013. There were 33 cases in total, including 25 males and 8 females, with mean age of 48.27 ± 8.7 years. There were 29 cases of Rockwood type III acromioclavicular dislocation, 4 cases of type V. The Constant-Murley shoulder function scoring system was used to evaluate the shoulder function recovery status after surgery. Anteroposterior shoulder X-ray was used to assess the position of the hook plate, status of acromioclavicular joint reduction and the occurrence of postoperative complications. According to the Constant-Murley shoulder function scoring system, the average scores were 78 ± 6 points 8 to 12 months after the surgery and before the removal of the hook plate, the average scores were 89 ± 5 minutes two months after the removal of hook plate. Postoperative X-ray imaging showed osteolysis in 10 cases (30.3%), osteoarthritis in six cases (18.1%), osteolysis associated with osteoarthritis in four cases(12.1%), and steel hook broken in one case (3%). The use of hook plate on open reduction and internal fixation of the acromioclavicular joint dislocation had little adverse effect on shoulder function and is an effective method for the treatment of acromioclavicular joint dislocation. Osteoarthritis and osteolysis are the two common complications after hook plate use, which are associated with the impairment of shoulder function. Shoulder function will be improved after removal of the hook plate.

Effects of hook plate on shoulder function after treatment of acromioclavicular joint dislocation

PubMed Central

Chen, Chang-Hong; Dong, Qi-Rong; Zhou, Rong-Kui; Zhen, Hua-Qing; Jiao, Ya-Jun

2014-01-01

Introduction: Internal fixation with hook plate has been used to treat acromioclavicular joint dislocation. This study aims to evaluate the effect of its use on shoulder function, to further analyze the contributing factors, and provide a basis for selection and design of improved internal fixation treatment of the acromioclavicular joint dislocation in the future. Methods: A retrospective analysis was performed on patients treated with a hook plate for acromioclavicular joint dislocation in our hospital from January 2010 to February 2013. There were 33 cases in total, including 25 males and 8 females, with mean age of 48.27 ± 8.7 years. There were 29 cases of Rockwood type III acromioclavicular dislocation, 4 cases of type V. The Constant-Murley shoulder function scoring system was used to evaluate the shoulder function recovery status after surgery. Anteroposterior shoulder X-ray was used to assess the position of the hook plate, status of acromioclavicular joint reduction and the occurrence of postoperative complications. Results: According to the Constant-Murley shoulder function scoring system, the average scores were 78 ± 6 points 8 to 12 months after the surgery and before the removal of the hook plate, the average scores were 89 ± 5 minutes two months after the removal of hook plate. Postoperative X-ray imaging showed osteolysis in 10 cases (30.3%), osteoarthritis in six cases (18.1%), osteolysis associated with osteoarthritis in four cases(12.1%), and steel hook broken in one case (3%). Conclusion: The use of hook plate on open reduction and internal fixation of the acromioclavicular joint dislocation had little adverse effect on shoulder function and is an effective method for the treatment of acromioclavicular joint dislocation. Osteoarthritis and osteolysis are the two common complications after hook plate use, which are associated with the impairment of shoulder function. Shoulder function will be improved after removal of the hook plate. PMID:25356110

Assessment of age of majority by measurement of open apices of the third molars using Cameriere's third molar maturity index.

PubMed

Sharma, Preeti; Wadhwan, Vijay; Ravi Prakash, S M; Aggarwal, Pooja; Sharma, Neeraj

2017-01-01

Evaluation of biological age of a living subject around the legal cutoff age for adulthood has become a grave concern for forensic experts in India, mainly due to the consequences of criminal obligations in judicial proceedings. Thus, this study was planned to examine the open apices of third molars in discriminating between individuals who are aged 18 years or older and who are not 18 years or older and to assign a cutoff for estimation of the age of 18 years. Orthopantomographs of 1062 individuals (14 and 23 years) were assessed, to verify Cameriere's third molar maturity index (I 3M ). The apical ends of the roots of the left mandibular third molar were analyzed. If the apical ends of the roots are completely closed, then I 3M is zero; otherwise, it is calculated as the sum of the distances between the inner sides of the two open apices divided by the tooth length. The sensitivity of the test for 0.08 value was 74.7% for males and 66% for females. Specificity was 83.6% for males and 79.6% for females. The probability that an Indian individual with an I 3M <0.08 in 18 years or older is 78% for males and 70.3% for females. I 3M is efficacious to determine age in Indian population.

Modeling Tight Junction Dynamics and Oscillations

PubMed Central

Kassab, Fuad; Marques, Ricardo Paulino; Lacaz-Vieira, Francisco

2002-01-01

Tight junction (TJ) permeability responds to changes of extracellular Ca2+ concentration. This can be gauged through changes of the transepithelial electrical conductance (G) determined in the absence of apical Na+. The early events of TJ dynamics were evaluated by the fast Ca2+ switch assay (FCSA) (Lacaz-Vieira, 2000), which consists of opening the TJs by removing basal calcium (Ca2+ bl) and closing by returning Ca2+ bl to normal values. Oscillations of TJ permeability were observed when Ca2+ bl is removed in the presence of apical calcium (Ca2+ ap) and were interpreted as resulting from oscillations of a feedback control loop which involves: (a) a sensor (the Ca2+ binding sites of zonula adhaerens), (b) a control unit (the cell signaling machinery), and (c) an effector (the TJs). A mathematical model to explain the dynamical behavior of the TJs and oscillations was developed. The extracellular route (ER), which comprises the paracellular space in series with the submucosal interstitial fluid, was modeled as a continuous aqueous medium having the TJ as a controlled barrier located at its apical end. The ER was approximated as a linear array of cells. The most apical cell is separated from the apical solution by the TJ and this cell bears the Ca2+ binding sites of zonula adhaerens that control the TJs. According to the model, the control unit receives information from the Ca2+ binding sites and delivers a signal that regulates the TJ barrier. Ca2+ moves along the ER according to one-dimensional diffusion following Fick's second law. Across the TJ, Ca2+ diffusion follows Fick's first law. Our first approach was to simulate the experimental results in a semiquantitative way. The model tested against experiment results performed in the frog urinary bladder adequately predicts the responses obtained in different experimental conditions, such as: (a) TJ opening and closing in a FCSA, (b) opening by the presence of apical Ca2+ and attainment of a new steady-state, (c) the escape phase which follows the halt of TJ opening induced by apical Ca2+, (d) the oscillations of TJ permeability, and (e) the effect of Ca2+ ap concentration on the frequency of oscillations. PMID:12149284

Apical pressure created during irrigation with the GentleWave™ system compared to conventional syringe irrigation.

PubMed

Haapasalo, Markus; Shen, Ya; Wang, Zhejun; Park, Ellen; Curtis, Allison; Patel, Payal; Vandrangi, Prashanthi

2016-09-01

The purpose of this study is to compare pressures at the apical foramen created by conventional syringe irrigation and the GentleWave™ System, which releases high-velocity degassed irrigants to the pulp chamber and uses broad-spectrum sound energy for cleaning. The apical pressure generated during irrigation was measured for palatal and distobuccal root canals of four extracted maxillary molars after no instrumentation, minimal instrumentation to a size #15/.04, instrumentation to a size #40/.04 taper, and after perforating the apical foramen to size #40. The root canals opened into an air-tight custom fixture coupled to a piezoresistive pressure transducer. Apical pressures were measured for the GentleWave™ System and syringe-needle irrigation at different irrigant flow rates, with the needle tip at 1 and 3 mm from the apical foramen using 30-gauge (G) open-ended or side-vented safety tip needles. The GentleWave™ System generated negative apical pressures (P < 0.001 compared with syringe irrigation); the mean pressures were between -13.07 and -17.19 mmHg. The 30 G needles could not reach the 1 and 3 mm from the working length in uninstrumented and 1 mm in minimally instrumented canals. The mean positive pressures between 6.46 and 110.34 mmHg were measured with needle irrigation depending on the flow rate, needle insertion depth, and size of the root canal. The GentleWave™ System creates negative pressure at the apical foramen during root canal cleaning irrespective of the size of canal instrumentation. Positive apical pressures were measured for syringe irrigation. Negative pressure during irrigation contributes to improved safety as compared to high-positive pressure.

Measurement of the force and torque produced in the calcium response of reactivated rat sperm flagella.

PubMed

Moritz, M J; Schmitz, K A; Lindemann, C B

2001-05-01

Rat sperm that are demembranated with Triton X-100 and reactivated with Mg-ATP show a strong mechanical response to the presence of free calcium ion. At pCa < 4, the midpiece region of the flagellum develops a strong and sustained curvature that gives the cell the overall appearance of a fishhook [Lindemann and Goltz, 1988: Cell Motil. Cytoskeleton 10:420-431]. In the present study, the force and torque that maintain the calcium-induced hook have been examined quantitatively. In addition, full-length and shortened flagella were manipulated to evaluate the plasticity of the hooks and determined the critical length necessary for maintaining the curvature. The hooks were found to be highly resilient, returning to their original configuration (>95%) after being straightened and released. The results from manipulating the shortened flagella suggest that the force holding the hook in the curved configuration is generated in the basal 60 microm of the flagellum. The force required to straighten the calcium-induced hooks was measured with force-calibrated glass microprobes, and the bending torque was calculated from the measured force. The force and torque required to straighten the flagellum were found to be proportional to the change in curvature of the hooked region of the flagellum, suggesting an elastic-like behavior. The average torque to open the hooks to a straight position was 2.6 (+/-1.4) x 10(-7) dyne x cm (2.6 x 10(-14) N x m) and the apparent stiffness was 4.3 (+/-1.3) x 10(-10) dyne x cm(2) (4.3 x 10(-19) N x m(2)). The stiffness of the hook was determined to be approximately one quarter the rigor stiffness of a rat sperm flagellum measured under comparable conditions.

Structural and genetic analysis of a mutant of Rhodobacter sphaeroides WS8 deficient in hook length control.

PubMed Central

González-Pedrajo, B; Ballado, T; Campos, A; Sockett, R E; Camarena, L; Dreyfus, G

1997-01-01

Motility in the photosynthetic bacterium Rhodobacter sphaeroides is achieved by the unidirectional rotation of a single subpolar flagellum. In this study, transposon mutagenesis was used to obtain nonmotile flagellar mutants from this bacterium. We report here the isolation and characterization of a mutant that shows a polyhook phenotype. Morphological characterization of the mutant was done by electron microscopy. Polyhooks were obtained by shearing and were used to purify the hook protein monomer (FlgE). The apparent molecular mass of the hook protein was 50 kDa. N-terminal amino acid sequencing and comparisons with the hook proteins of other flagellated bacteria indicated that the Rhodobacter hook protein has consensus sequences common to axial flagellar components. A 25-kb fragment from an R. sphaeroides WS8 cosmid library restored wild-type flagellation and motility to the mutant. Using DNA adjacent to the inserted transposon as a probe, we identified a 4.6-kb SalI restriction fragment that contained the gene responsible for the polyhook phenotype. Nucleotide sequence analysis of this region revealed an open reading frame with a deduced amino acid sequence that was 23.4% identical to that of FliK of Salmonella typhimurium, the polypeptide responsible for hook length control in that enteric bacterium. The relevance of a gene homologous to fliK in the uniflagellated bacterium R. sphaeroides is discussed. PMID:9352903

Assessment of age of majority by measurement of open apices of the third molars using Cameriere's third molar maturity index

PubMed Central

Sharma, Preeti; Wadhwan, Vijay; Ravi Prakash, S. M.; Aggarwal, Pooja; Sharma, Neeraj

2017-01-01

Aims and Objectives: Evaluation of biological age of a living subject around the legal cutoff age for adulthood has become a grave concern for forensic experts in India, mainly due to the consequences of criminal obligations in judicial proceedings. Thus, this study was planned to examine the open apices of third molars in discriminating between individuals who are aged 18 years or older and who are not 18 years or older and to assign a cutoff for estimation of the age of 18 years. Materials and Methods: Orthopantomographs of 1062 individuals (14 and 23 years) were assessed, to verify Cameriere's third molar maturity index (I3M). The apical ends of the roots of the left mandibular third molar were analyzed. If the apical ends of the roots are completely closed, then I3Mis zero; otherwise, it is calculated as the sum of the distances between the inner sides of the two open apices divided by the tooth length. Results and Conclusion: The sensitivity of the test for 0.08 value was 74.7% for males and 66% for females. Specificity was 83.6% for males and 79.6% for females. The probability that an Indian individual with an I3M<0.08 in 18 years or older is 78% for males and 70.3% for females. I3Mis efficacious to determine age in Indian population. PMID:29263615

Irrigation dynamics associated with positive pressure, apical negative pressure and passive ultrasonic irrigations: a computational fluid dynamics analysis.

PubMed

Chen, José Enrique; Nurbakhsh, Babak; Layton, Gillian; Bussmann, Markus; Kishen, Anil

2014-08-01

Complexities in root canal anatomy and surface adherent biofilm structures remain as challenges in endodontic disinfection. The ability of an irrigant to penetrate into the apical region of a canal, along with its interaction with the root canal walls, will aid in endodontic disinfection. The aim of this study was to qualitatively examine the irrigation dynamics of syringe irrigation with different needle tip designs (open-ended and closed-ended), apical negative pressure irrigation with the EndoVac® system, and passive ultrasonic-assisted irrigation, using a computational fluid dynamics model. Syringe-based irrigation with a side-vented needle showed a higher wall shear stress than the open-ended but was localised to a small region of the canal wall. The apical negative pressure mode of irrigation generated the lowest wall shear stress, while the passive-ultrasonic irrigation group showed the highest wall shear stress along with the greatest magnitude of velocity. © 2013 The Authors. Australian Endodontic Journal © 2013 Australian Society of Endodontology.

Treatment of Necrotic Teeth by Apical Revascularization: Meta-analysis.

PubMed

He, Ling; Zhong, Juan; Gong, Qimei; Kim, Sahng G; Zeichner, Samuel J; Xiang, Lusai; Ye, Ling; Zhou, Xuedong; Zheng, Jinxuan; Liu, Yongxing; Guan, Chenyu; Cheng, Bin; Ling, Junqi; Mao, Jeremy J

2017-10-24

Each year ~5.4 million children and adolescents in the United States suffer from dental infections, leading to pulp necrosis, arrested tooth-root development and tooth loss. Apical revascularization, adopted by the American Dental Association for its perceived ability to enable postoperative tooth-root growth, is being accepted worldwide. The objective of the present study is to perform a meta-analysis on apical revascularization. Literature search yielded 22 studies following PRISMA with pre-defined inclusion and exclusion criteria. Intraclass correlation coefficient was calculated to account for inter-examiner variation. Following apical revascularization with 6- to 66-month recalls, root apices remained open in 13.9% cases (types I), whereas apical calcification bridge formed in 47.2% (type II) and apical closure (type III) in 38.9% cases. Tooth-root lengths lacked significant postoperative gain among all subjects (p = 0.3472) or in subgroups. Root-dentin area showed significant increases in type III, but not in types I or II cases. Root apices narrowed significantly in types II and III, but not in type I patients. Thus, apical revascularization facilitates tooth-root development but lacks consistency in promoting root lengthening, widening or apical closure. Post-operative tooth-root development in immature permanent teeth represents a generalized challenge to regenerate diseased pediatric tissues that must grow to avoid organ defects.

A nonsurgical endodontic treatment in open-apex and immature teeth affected by dens invaginatus: using a collagen membrane as an apical barrier.

PubMed

Gharechahi, Maryam; Ghoddusi, Jamileh

2012-02-01

The authors' objective in this case report is to demonstrate an effective nonsurgical endodontic treatment in open-apex teeth affected by dens invaginatus (DI) by using a collagen membrane as an apical barrier and using a mineral trioxide aggregate (MTA) apical plug. . The authors present two cases of DI with open apexes in maxillary lateral incisors. In the first case, an adolescent had bilateral Oehlers type II DI and extensive periradicular radiolucency, internal root resorption and a vestibular fistula in the left maxillary lateral incisor. In the second case, an adult had Oehlers type II DI and an incomplete apex in the left maxillary lateral incisor. For both patients, the clinician placed a collagen membrane through the apexes of the left maxillary incisors to provide a resorbable extraradicular barrier against which MTA cement could be packed. The clinician obturated the adolescent's right lateral incisor. In the adolescent, the vestibular sinus tract was closed after one week. At subsequent follow-up examinations, the periradicular regions were completely healed, and postoperative radiographs revealed good bone healing in the lateral incisors. The teeth were asymptomatic and healing was achieved without any need for further endodontic surgical intervention. In the adult patient, the tooth was symptom free after one week, and radiography performed six months after the procedure showed complete healing. and Despite complex anatomy and diagnoses of DI and open apexes, both patients successfully underwent nonsurgical endodontic treatment involving the use of a collagen membrane and an MTA apical plug. Using an extraradicular barrier clinically can help improve the adaptation of MTA in the apexes of open-apex teeth to achieve a complete seal.

K+ channel openers restore verapamil-inhibited lung fluid resolution and transepithelial ion transport

PubMed Central

2010-01-01

Background Lung epithelial Na+ channels (ENaC) are regulated by cell Ca2+ signal, which may contribute to calcium antagonist-induced noncardiogenic lung edema. Although K+ channel modulators regulate ENaC activity in normal lungs, the therapeutical relevance and the underlying mechanisms have not been completely explored. We hypothesized that K+ channel openers may restore calcium channel blocker-inhibited alveolar fluid clearance (AFC) by up-regulating both apical and basolateral ion transport. Methods Verapamil-induced depression of heterologously expressed human αβγ ENaC in Xenopus oocytes, apical and basolateral ion transport in monolayers of human lung epithelial cells (H441), and in vivo alveolar fluid clearance were measured, respectively, using the two-electrode voltage clamp, Ussing chamber, and BSA protein assays. Ca2+ signal in H441 cells was analyzed using Fluo 4AM. Results The rate of in vivo AFC was reduced significantly (40.6 ± 6.3% of control, P < 0.05, n = 12) in mice intratracheally administrated verapamil. KCa3.1 (1-EBIO) and KATP (minoxidil) channel openers significantly recovered AFC. In addition to short-circuit current (Isc) in intact H441 monolayers, both apical and basolateral Isc levels were reduced by verapamil in permeabilized monolayers. Moreover, verapamil significantly altered Ca2+ signal evoked by ionomycin in H441 cells. Depletion of cytosolic Ca2+ in αβγ ENaC-expressing oocytes completely abolished verapamil-induced inhibition. Intriguingly, KV (pyrithione-Na), K Ca3.1 (1-EBIO), and KATP (minoxidil) channel openers almost completely restored the verapamil-induced decrease in Isc levels by diversely up-regulating apical and basolateral Na+ and K+ transport pathways. Conclusions Our observations demonstrate that K+ channel openers are capable of rescuing reduced vectorial Na+ transport across lung epithelial cells with impaired Ca2+ signal. PMID:20507598

76 FR 64300 - Submission for OMB Review; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-18

... Halibut and Sablefish IFQ Program provides economic stability for the commercial hook-and-line fishery... years of management as an open access fishery, while maintaining the social and economic character of...

"Guy Reader" Is Not an Oxymoron

ERIC Educational Resources Information Center

Korman, Gordon

2013-01-01

The author of 80 books, most recently "HYPNOTIZE ME," discusses the unique challenges of engaging reluctant and sometimes openly hostile boys by creating the kind of stories that will hook them in and turn them into lifelong readers.

Optimizing python-based ROOT I/O with PyPy's tracing just-in-time compiler

NASA Astrophysics Data System (ADS)

Tlp Lavrijsen, Wim

2012-12-01

The Python programming language allows objects and classes to respond dynamically to the execution environment. Most of this, however, is made possible through language hooks which by definition can not be optimized and thus tend to be slow. The PyPy implementation of Python includes a tracing just in time compiler (JIT), which allows similar dynamic responses but at the interpreter-, rather than the application-level. Therefore, it is possible to fully remove the hooks, leaving only the dynamic response, in the optimization stage for hot loops, if the types of interest are opened up to the JIT. A general opening up of types to the JIT, based on reflection information, has already been developed (cppyy). The work described in this paper takes it one step further by customizing access to ROOT I/O to the JIT, allowing for fully automatic optimizations.

Robust tilt and lock mechanism for hopping actuator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Salton, Jonathan R.; Buerger, Stephen; Dullea, Kevin J.

A tilt and lock apparatus that includes a tilt servomechanism, a spiral torsion spring, a lock wheel, and a lock hook is described herein. The spiral torsion spring is mechanically coupled to the tilt servomechanism and the lock wheel (which includes an opening). When a shaft is positioned through the opening, rotation of the lock wheel is in unison with rotation of the shaft. An external surface of the lock wheel includes one or more grooves. The lock hook includes a head that engages and disengages the grooves. The lock wheel is stationary when the head engages one of themore » grooves and is rotatable when the head disengages the grooves. The head and the grooves are geometrically aligned when engaged to prevent creation of a force that acts to disengage the head responsive to an applied force acting on the shaft.« less

An animal model to study regenerative endodontics.

PubMed

Torabinejad, Mahmoud; Corr, Robert; Buhrley, Matthew; Wright, Kenneth; Shabahang, Shahrokh

2011-02-01

A growing body of evidence is demonstrating the possibility for regeneration of tissues within the pulp space and continued root development in teeth with necrotic pulps and open apices. There are areas of research related to regenerative endodontics that need to be investigated in an animal model. The purpose of this study was to investigate ferret cuspid teeth as a model to investigate factors involved in regenerative endodontics. Six young male ferrets between the ages of 36-133 days were used in this investigation. Each animal was anesthetized and perfused with 10% buffered formalin. Block sections including the mandibular and maxillary cuspid teeth and their surrounding periapical tissues were obtained, radiographed, decalcified, sectioned, and stained with hematoxylin-eosin to determine various stages of apical closure in these teeth. The permanent mandibular and maxillary cuspid teeth with open apices erupted approximately 50 days after birth. Initial signs of closure of the apical foramen in these teeth were observed between 90-110 days. Complete apical closure was observed in the cuspid teeth when the animals were 133 days old. Based on the experiment, ferret cuspid teeth can be used to investigate various factors involved in regenerative endodontics that cannot be tested in human subjects. The most appropriate time to conduct the experiments would be when the ferrets are between the ages of 50 and 90 days. Copyright © 2011. Published by Elsevier Inc.

Glove box on vehicular instrument panel

DOEpatents

Atarashi, Kazuya

1985-01-01

A glove box for the upper surface of an automobile dashboard whereby it may be positioned close to the driver. The glove box lid is pivotally supported by arms extending down either side to swing forwardly for opening. A hook is pivotally support adjacent an arm and weighted to swing into engagement with the arm to prevent opening of the lid during abrupt deceleration. A toggle spring assists in maintaining the lid in either the open or closed position.

Closet in room #17, bunkhouse, second floor interior. Originally a ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Closet in room #17, bunkhouse, second floor interior. Originally a shelf and coat hooks, this was modified with a drawer and door, enclosing the open closet. - Sespe Ranch, Bunkhouse, 2896 Telegraph Road, Fillmore, Ventura County, CA

Recombinant Amelogenin Protein Induces Apical Closure and Pulp Regeneration in Open-apex, Non-vital Permanent Canine Teeth

PubMed Central

Mounir, Maha M.F.; Matar, Moustafa A.; Lei, Yaping; Snead, Malcolm L.

2015-01-01

Introduction Recombinant DNA produced amelogenin protein was compared to calcium hydroxide in a study of immature apex closure conducted in 24 young mongrel dogs. Methods Root canals of maxillary and mandibular right premolars (n = 240) were instrumented and left open for 14 days. Canals were cleansed, irrigated and split equally for treatment with recombinant mouse amelogenin (n = 120) or calcium hydroxide (n = 120). Results After 1, 3, and 6 months, the animals were sacrificed and the treated teeth recovered for histological assessment and immunodetection of protein markers associated with odontogenic cells. After 1 month, amelogenin-treated canals revealed calcified tissue formed at the apical foramen and a pulp chamber containing soft connective tissue and hard tissue; amelogenin-treated canals assessed after 3 and 6 month intervals further included apical tissue functionally attached to bone by a periodontal ligament. In contrast, calcified apical tissue was poorly formed in the calcium hydroxide group and soft connective tissue within the pulp chamber was not observed. Conclusions The findings from this experimental strategy suggest recombinant amelogenin protein can signal cells to enhance apex formation in non-vital immature teeth and promote soft connective tissue regeneration. PMID:26709200

The clavicle hook plate for Neer type II lateral clavicle fractures.

PubMed

Renger, R J; Roukema, G R; Reurings, J C; Raams, P M; Font, J; Verleisdonk, E J M M

2009-09-01

To evaluate functional and radiologic outcome in patients with a Neer type II lateral clavicle fracture treated with the clavicle hook plate. Multicenter retrospective study. Five level I and II trauma centers. Forty-four patients, average age 38.4 years (18-66 years), with a Neer type II lateral clavicle fracture treated with the clavicle hook plate between January 1, 2003, and December 31, 2006. Open reduction and internal fixation with the clavicle hook plate. Removal of all 44 implants after consolidation at a mean of 8.4 months (2-33 months) postoperatively. At an average follow-up of 27.4 months (13-48 months), functional outcome was assessed with the Constant-Murley scoring system. Radiographs were taken to evaluate consolidation and to determine the distance between the coracoid process and the clavicle. The average Constant score was 92.4 (74-100). The average distance between the coracoid process and the clavicle was 9.8 mm (7.3-14.8 mm) compared with 9.4 mm (6.9-14.3 mm) on the contralateral nonoperative side. We observed 1 dislocation of an implant (2.2%), 2 cases of pseudarthrosis (4.5%), 2 superficial wound infections (4.5%), 2 patients with hypertrophic scar tissue (4.5%), and 3 times an acromial osteolysis (6.8%). Thirty patients (68%) reported discomfort due to the implant. These implant-related complaints and the acromial osteolysis disappeared after removal of the hook plate. With all the patients, direct functional aftercare was possible. The clavicle hook plate is a suitable implant for Neer type II clavicle fractures. The advantage of this osteosynthesis is the possibility of immediate functional aftercare. We observed a high percentage of discomfort due to the implant; therefore, we advise to remove the implant as soon as consolidation has taken place.

Genome-wide regulation of light-controlled seedling morphogenesis by three families of transcription factors.

PubMed

Shi, Hui; Lyu, Mohan; Luo, Yiwen; Liu, Shoucheng; Li, Yue; He, Hang; Wei, Ning; Deng, Xing Wang; Zhong, Shangwei

2018-06-19

Three families of transcription factors have been reported to play key roles in light control of Arabidopsis seedling morphogenesis. Among them, bHLH protein PIFs and plant-specific protein EIN3/EIN3-LIKE 1 (EIN3/EIL1) accumulate in the dark to maintain skotomorphogenesis. On the other hand, HY5 and HY5 HOMOLOG (HYH), two related bZIP proteins, are stabilized in light and promote photomorphogenic development. To systemically investigate the transcriptional regulation of light-controlled seedling morphogenesis, we generated HY5 ox/ pifQein3eil1 , which contained mutations of EIN3/EIL1 and four PIF genes ( pifQein3eil1 ) and overexpression of HY5 Our results show that dark-grown HY5 ox/ pifQein3eil1 seedlings display a photomorphogenesis highly similar to that of wild-type seedlings grown in continuous light, with remarkably enhanced photomorphogenic phenotypes compared with the pifQ mutants. Consistent with the genetic evidence, transcriptome analysis indicated that PIFs, EIN3/EIL1, and HY5 are dominant transcription factors in collectively mediating a wide range of light-caused genome-wide transcriptional changes. Moreover, PIFs and EIN3/EIL1 independently control the expression of light-regulated genes such as HLS1 to cooperatively regulate apical hook formation, hypocotyl elongation, and cotyledon opening and expansion. This study illustrates a comprehensive regulatory network of transcription activities that correspond to specific morphological aspects in seedling skotomorphogenesis and photomorphogenesis.

TOPP4 Regulates the Stability of PHYTOCHROME INTERACTING FACTOR5 during Photomorphogenesis in Arabidopsis1

PubMed Central

Qin, Qianqian; Meng, Siyuan; Li, Jia; Hou, Suiwen

2015-01-01

In plants, photoreceptors transfer light signals to phytochrome-interacting factors (PIFs), inducing the rapid phosphorylation and degradation of PIFs to promote photomorphogenesis. However, the phosphatase responsible for PIF dephosphorylation remains unknown. In this study, we identified a type 1 protein phosphatase, TOPP4, that is essential for PIF5 protein stability in Arabidopsis (Arabidopsis thaliana). Compared with the wild type, the dominant-negative mutant, topp4-1, displayed reduced hypocotyl length and larger apical hook and cotyledon opening angle under red light. Overexpression of topp4-1 in the wild type led to defects that were similar to those in the topp4-1 mutant. Red light induced phytochrome B (phyB)-dependent TOPP4 expression in hypocotyls. The topp4-1 mutation weakened the closed cotyledon angle of phyB-9 and phyA-211 phyB-9, while overexpression of TOPP4 significantly repressed the short hypocotyls of phyB-green fluorescent protein seedlings, indicating that TOPP4 and phyB function in an antagonistic way during photomorphogenesis. Protein interaction assays and phosphorylation studies demonstrate that TOPP4 interacts directly with PIF5 and dephosphorylates it. Furthermore, TOPP4 inhibits the red light-induced ubiquitination and degradation of PIF5. These findings demonstrate that dephosphorylation of PIF5 by TOPP4 inhibits its ubiquitin-mediated degradation during photomorphogenesis. These data outline a novel phytochrome signaling mechanism by which TOPP4-mediated dephosphorylation of PIF5 attenuates phytochrome-dependent light responses. PMID:26704640

HYPOTrace: image analysis software for measuring hypocotyl growth and shape demonstrated on Arabidopsis seedlings undergoing photomorphogenesis.

PubMed

Wang, Liya; Uilecan, Ioan Vlad; Assadi, Amir H; Kozmik, Christine A; Spalding, Edgar P

2009-04-01

Analysis of time series of images can quantify plant growth and development, including the effects of genetic mutations (phenotypes) that give information about gene function. Here is demonstrated a software application named HYPOTrace that automatically extracts growth and shape information from electronic gray-scale images of Arabidopsis (Arabidopsis thaliana) seedlings. Key to the method is the iterative application of adaptive local principal components analysis to extract a set of ordered midline points (medial axis) from images of the seedling hypocotyl. Pixel intensity is weighted to avoid the medial axis being diverted by the cotyledons in areas where the two come in contact. An intensity feature useful for terminating the midline at the hypocotyl apex was isolated in each image by subtracting the baseline with a robust local regression algorithm. Applying the algorithm to time series of images of Arabidopsis seedlings responding to light resulted in automatic quantification of hypocotyl growth rate, apical hook opening, and phototropic bending with high spatiotemporal resolution. These functions are demonstrated here on wild-type, cryptochrome1, and phototropin1 seedlings for the purpose of showing that HYPOTrace generated expected results and to show how much richer the machine-vision description is compared to methods more typical in plant biology. HYPOTrace is expected to benefit seedling development research, particularly in the photomorphogenesis field, by replacing many tedious, error-prone manual measurements with a precise, largely automated computational tool.

Reformulated gasoline deal with Venezuela draws heat

DOE Office of Scientific and Technical Information (OSTI.GOV)

Begley, R.

A fight is brewing in Congress over a deal to let Venezuela off the hook in complying with the Clean Air Act reformulated gasoline rule. When Venezuela threatened to call for a GATT panel to challenge the rule as a trade barrier, the Clinton Administration negotiated to alter the rule, a deal that members of Congress are characterizing as {open_quotes}secret{close_quotes} and {open_quotes}back door.{close_quotes}

Recombinant Amelogenin Protein Induces Apical Closure and Pulp Regeneration in Open-apex, Nonvital Permanent Canine Teeth.

PubMed

Mounir, Maha M F; Matar, Moustafa A; Lei, Yaping; Snead, Malcolm L

2016-03-01

Recombinant DNA-produced amelogenin protein was compared with calcium hydroxide in a study of immature apex closure conducted in 24 young mongrel dogs. Root canals of maxillary and mandibular right premolars (n = 240) were instrumented and left open for 14 days. Canals were cleansed, irrigated, and split equally for treatment with recombinant mouse amelogenin (n = 120) or calcium hydroxide (n = 120). After 1, 3, and 6 months, the animals were sacrificed and the treated teeth recovered for histologic assessment and immunodetection of protein markers associated with odontogenic cells. After 1 month, amelogenin-treated canals revealed calcified tissue formed at the apical foramen and a pulp chamber containing soft connective tissue and hard tissue; amelogenin-treated canals assessed after 3- and 6-month intervals further included apical tissue functionally attached to bone by a periodontal ligament. In contrast, calcified apical tissue was poorly formed in the calcium hydroxide group, and soft connective tissue within the pulp chamber was not observed. The findings from this experimental strategy suggest recombinant amelogenin protein can signal cells to enhance apex formation in nonvital immature teeth and promote soft connective tissue regeneration. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Irrigation of human prepared root canal – ex vivo based computational fluid dynamics analysis

PubMed Central

Šnjarić, Damir; Čarija, Zoran; Braut, Alen; Halaji, Adelaida; Kovačević, Maja; Kuiš, Davor

2012-01-01

Aim To analyze the influence of the needle type, insertion depth, and irrigant flow rate on irrigant flow pattern, flow velocity, and apical pressure by ex-vivo based endodontic irrigation computational fluid dynamics (CFD) analysis. Methods Human upper canine root canal was prepared using rotary files. Contrast fluid was introduced in the root canal and scanned by computed tomography (CT) providing a three-dimensional object that was exported to the computer-assisted design (CAD) software. Two probe points were established in the apical portion of the root canal model for flow velocity and pressure measurement. Three different CAD models of 27G irrigation needles (closed-end side-vented, notched open-end, and bevel open-end) were created and placed at 25, 50, 75, and 95% of the working length (WL). Flow rates of 0.05, 0.1, 0.2, 0.3, and 0.4 mL/s were simulated. A total of 60 irrigation simulations were performed by CFD fluid flow solver. Results Closed-end side-vented needle required insertion depth closer to WL, regarding efficient irrigant replacement, compared to open-end irrigation needle types, which besides increased velocity produced increased irrigant apical pressure. For all irrigation needle types and needle insertion depths, the increase of flow rate was followed by an increased irrigant apical pressure. Conclusions The human root canal shape obtained by CT is applicable in the CFD analysis of endodontic irrigation. All the analyzed values –irrigant flow pattern, velocity, and pressure – were influenced by irrigation needle type, as well as needle insertion depth and irrigant flow rate. PMID:23100209

Irrigation of human prepared root canal--ex vivo based computational fluid dynamics analysis.

PubMed

Snjaric, Damir; Carija, Zoran; Braut, Alen; Halaji, Adelaida; Kovacevic, Maja; Kuis, Davor

2012-10-01

To analyze the influence of the needle type, insertion depth, and irrigant flow rate on irrigant flow pattern, flow velocity, and apical pressure by ex-vivo based endodontic irrigation computational fluid dynamics (CFD) analysis. Human upper canine root canal was prepared using rotary files. Contrast fluid was introduced in the root canal and scanned by computed tomography (CT) providing a three-dimensional object that was exported to the computer-assisted design (CAD) software. Two probe points were established in the apical portion of the root canal model for flow velocity and pressure measurement. Three different CAD models of 27G irrigation needles (closed-end side-vented, notched open-end, and bevel open-end) were created and placed at 25, 50, 75, and 95% of the working length (WL). Flow rates of 0.05, 0.1, 0.2, 0.3, and 0.4 mL/s were simulated. A total of 60 irrigation simulations were performed by CFD fluid flow solver. Closed-end side-vented needle required insertion depth closer to WL, regarding efficient irrigant replacement, compared to open-end irrigation needle types, which besides increased velocity produced increased irrigant apical pressure. For all irrigation needle types and needle insertion depths, the increase of flow rate was followed by an increased irrigant apical pressure. The human root canal shape obtained by CT is applicable in the CFD analysis of endodontic irrigation. All the analyzed values -irrigant flow pattern, velocity, and pressure - were influenced by irrigation needle type, as well as needle insertion depth and irrigant flow rate.

Sealing ability, marginal adaptation and their correlation using three root-end filling materials as apical plugs

PubMed Central

OROSCO, Fernando Accorsi; BRAMANTE, Clovis Monteiro; GARCIA, Roberto Brandão; BERNARDINELI, Norberti; de MORAES, Ivaldo Gomes

2010-01-01

Objective This study used dye leakage assay and scanning electron microscopy to evaluate, respectively, the sealing ability and marginal adaptation of three root-end filling materials used as apical plugs, as well as the possible correlation between these properties. Material and Methods Ninety-eight single-rooted human teeth were prepared to simulate an open apex. The teeth were allocated to three experimental groups (n = 30), which received a 5-mm thick apical plug of (1) gray MTA AngelusTM, (2) CPMTM and (3) MBPc, and two controls groups (n = 4). After immersion in 0.2% Rhodamine B solution for 48 h, the teeth were sectioned longitudinally and analyzed by Image Tool 3.0 software. The marginal adaptation between apical plugs and the root canal walls were analyzed by SEM. Results MBPc had significantly less (p<0.05) apical leakage than the other materials. Regarding marginal adaptation, CPMTM showed the best numerical results, though without statistical significance from the other materials (p<0.05). There was no correlation between the two properties. Conclusions When used as apical plugs, the tested root-end filling materials had similar marginal adaptation to the dentin walls, but MBPc had the best sealing ability, as demonstrated by the least apical leakage from all tested materials. PMID:20485923

49 CFR 176.104 - Loading and unloading Class 1 (explosive) materials.

Code of Federal Regulations, 2012 CFR

2012-10-01

... is formed by use of an open hook may not be used in handling Class 1 (explosive) materials. (e) Only... feet) long, and 10 cm (3.9 inches) thick, and be made of woven hemp, sisal, or similar fiber, or foam...

49 CFR 176.104 - Loading and unloading Class 1 (explosive) materials.

Code of Federal Regulations, 2011 CFR

2011-10-01

... is formed by use of an open hook may not be used in handling Class 1 (explosive) materials. (e) Only... feet) long, and 10 cm (3.9 inches) thick, and be made of woven hemp, sisal, or similar fiber, or foam...

49 CFR 176.104 - Loading and unloading Class 1 (explosive) materials.

Code of Federal Regulations, 2013 CFR

2013-10-01

... is formed by use of an open hook may not be used in handling Class 1 (explosive) materials. (e) Only... feet) long, and 10 cm (3.9 inches) thick, and be made of woven hemp, sisal, or similar fiber, or foam...

49 CFR 176.104 - Loading and unloading Class 1 (explosive) materials.

Code of Federal Regulations, 2010 CFR

2010-10-01

... is formed by use of an open hook may not be used in handling Class 1 (explosive) materials. (e) Only... feet) long, and 10 cm (3.9 inches) thick, and be made of woven hemp, sisal, or similar fiber, or foam...

49 CFR 176.104 - Loading and unloading Class 1 (explosive) materials.

Code of Federal Regulations, 2014 CFR

2014-10-01

... is formed by use of an open hook may not be used in handling Class 1 (explosive) materials. (e) Only... feet) long, and 10 cm (3.9 inches) thick, and be made of woven hemp, sisal, or similar fiber, or foam...

Energy Absorbing Countermass for Shoulder-Launched Rocket Weapon

DTIC Science & Technology

2000-01-05

of the countermass 16, cause the leaves 22 to open. 6 NAVY CASE 7 8477 PATENT Contained within the countermass 16 is a rippable envelope 36...open, disengaging hooks on the aft ends of the leaves, the rippable polypropolene envelope 36 separates allowing the frangible mass 38 to be dispersed...A portion of the rippable envelope 36 10 remains attached to a plastic endcap 44. The frangible countermass may be any material having high

Revitalization of open apex teeth with apical periodontitis using a collagen-hydroxyapatite scaffold.

PubMed

Nevins, Alan J; Cymerman, Jerome J

2015-06-01

An enhanced revision of the revitalization endodontic technique for immature teeth with apical periodontitis has been described. It includes the addition of collagen-hydroxyapatite scaffold to the currently practiced revascularization technique. Four cases treated in series are presented in this report, 1 case involving 2 teeth. Periapical diagnoses of immature teeth included "asymptomatic apical periodontitis," "symptomatic apical periodontitis," and "acute apical abscess." Additionally, 1 fully developed tooth that had undergone root canal treatment that failed had a periapical diagnosis of acute apical abscess. An established revascularization protocol was used for all teeth. In addition to stimulating blood clots, all teeth were filled with collagen-hydroxyapatite scaffolds. Periapical radiolucencies healed in all teeth, and diffuse radiopacity developed within the coronal portions of canal spaces. Root development with root lengthening occurred in the immature nonvital maxillary premolar that had not undergone prior treatment. The technique of adding a collagen-hydroxyapatite scaffold to the existing revitalization protocol has been described in which substantial hard tissue repair has occurred. This may leave teeth more fully developed and less likely to fracture. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

The APIC research agenda: results from a national survey.

PubMed

Wright, Marc-Oliver; Carter, Eileen; Pogorzelska, Monika; Murphy, Cathryn; Hanchett, Marilyn; Stone, Patricia W

2012-05-01

Research is an integral component of the Association for Professionals in Infection Control and Epidemiology (APIC) Strategic Plan 2020. As the role of the infection preventionist (IP) has evolved toward consumers and implementers of research, it becomes increasingly necessary to assess which topics require further evidence and how best APIC can assist IPs. In 2010, APIC determined that the research priorities first described in 2000 needed to be re-evaluated. A 33-question Web-based survey was developed and distributed via e-mail to APIC members in March 2011. The survey contained sections inquiring about respondents' demographics, familiarity with implementation science, and infection prevention research priorities. Priorities identified by a Delphi study 10 years ago were re-ranked, and open-ended items were used to identify new research priorities and understand how APIC could best serve its members in relation to research. Seven hundred one members responded. Behavioral management science, surveillance standards, and infection prevention resource optimization were the highest ranked priorities and relatively unchanged from 2000. Proposed additional research topics focused on achieving standardization in infection prevention practices and program resource allocation. The majority of respondents described APIC's role in the field of research as a disseminator of low-cost, highly accessible education to its members. This report should be used as a roadmap for APIC leadership as it provides suggestions on how APIC may best direct the association's research program. The major research priorities described and ranked in 2000 continue to challenge IPs. APIC can best serve its members by disseminating research findings in a cost-effective and easily accessed manner. Recurrent assessments of research priorities can help guide researchers and policy makers and help determine which topics will best support successful infection prevention processes and outcomes. Published by Mosby, Inc.

Democratic Foundations for Spiritually Responsive Pedagogy

ERIC Educational Resources Information Center

Lingley, Audrey

2016-01-01

Spirituality has been identified as an important component of democratic education by influential scholars such as Dewey, Freire, hooks, and Noddings. However, many teachers in the United States do not engage openly with a framework for understanding, organizing, and integrating pedagogical knowledge of spirituality within the context of…

Gravitropic moss cells default to spiral growth on the clinostat and in microgravity during spaceflight

NASA Technical Reports Server (NTRS)

Kern, Volker D.; Schwuchow, Jochen M.; Reed, David W.; Nadeau, Jeanette A.; Lucas, Jessica; Skripnikov, Alexander; Sack, Fred D.

2005-01-01

In addition to shoots and roots, the gravity (g)-vector orients the growth of specialized cells such as the apical cell of dark-grown moss protonemata. Each apical cell of the moss Ceratodon purpureus senses the g-vector and adjusts polar growth accordingly producing entire cultures of upright protonemata (negative gravitropism). The effect of withdrawing a constant gravity stimulus on moss growth was studied on two NASA Space Shuttle (STS) missions as well as during clinostat rotation on earth. Cultures grown in microgravity (spaceflight) on the STS-87 mission exhibited two successive phases of non-random growth and patterning, a radial outgrowth followed by the formation of net clockwise spiral growth. Also, cultures pre-aligned by unilateral light developed clockwise hooks during the subsequent dark period. The second spaceflight experiment flew on STS-107 which disintegrated during its descent on 1 February 2003. However, most of the moss experimental hardware was recovered on the ground, and most cultures, which had been chemically fixed during spaceflight, were retrieved. Almost all intact STS-107 cultures displayed strong spiral growth. Non-random culture growth including clockwise spiral growth was also observed after clinostat rotation. Together these data demonstrate the existence of default non-random growth patterns that develop at a population level in microgravity, a response that must normally be overridden and masked by a constant g-vector on earth.

Effects on auditory-nerve fibers of opening the otic capsule at the apex of the chinchilla cochlea

NASA Astrophysics Data System (ADS)

Recio-Spinoso, Alberto; Temchin, Andrei N.; Ruggero, Mario A.

2015-12-01

Vibration responses to clicks measured at the apex of chinchilla cochleae with open otic capsules have onsets much shorter than those of responses of auditory-nerve fibers (ANFs) corrected for synaptic and neural delays. Apical vibration responses to tones in open cochleae also differ in other respects from the responses to tones of ANFs with low characteristic frequency (CF) in normal chinchilla cochleae. To further specify the origin(s) of these differences, we recorded from chinchilla ANFs after delicately opening a small hole in the otic capsule overlying scala vestibuli in the cochlear apex. In those cochleae, the earliest ANF responses to clicks are often evoked by condensation (rather than rarefaction) clicks and responses to tones often exhibit level-dependent phase changes different from those in normal cochleae. These findings are largely consistent with, and seem to account for, apical vibration responses of cochleae with open otic capsules. An unexpected finding is that the tuning curves of ANFs with moderately high CF and normal CF thresholds often had hypersensitive tails.

Hooked on E-Mail

ERIC Educational Resources Information Center

Espinoza, Kathy

2011-01-01

Information overload, and an expectation that e-mails, tweets, and text messages will be answered immediately, impact productivity. The younger, information-addicted workers have a greater capacity to process this open floodgate of information, as well as a better ability to multitask. Research suggests that there is a marked drop in worker…

Regulation of seedling growth by ethylene and the ethylene-auxin crosstalk.

PubMed

Hu, Yuming; Vandenbussche, Filip; Van Der Straeten, Dominique

2017-03-01

This review highlights that the auxin gradient, established by local auxin biosynthesis and transport, can be controlled by ethylene, and steers seedling growth. A better understanding of the mechanisms in Arabidopsis will increase potential applications in crop species. In dark-grown Arabidopsis seedlings, exogenous ethylene treatment triggers an exaggeration of the apical hook, the inhibition of both hypocotyl and root elongation, and radial swelling of the hypocotyl. These features are predominantly based on the differential cell elongation in different cells/tissues mediated by an auxin gradient. Interestingly, the physiological responses regulated by ethylene and auxin crosstalk can be either additive or synergistic, as in primary root and root hair elongation, or antagonistic, as in hypocotyl elongation. This review focuses on the crosstalk of these two hormones at the seedling stage. Before illustrating the crosstalk, ethylene and auxin biosynthesis, metabolism, transport and signaling are briefly discussed.

Acanthocephalans from fishes and amphibians in Vietnam, with descriptions of five new species

PubMed Central

2014-01-01

Eight species of acanthocephalans are reported, and five are new. Specimens of Neoechinorhynchus (Hebesoma) manubrianus Amin, Ha & Ha, 2011 were similar to the original description. Neoechinorhynchus (Hebesoma) spiramuscularis n. sp. (Neoechinorhynchidae), from Xenocypris davidi, has a unique proboscis receptacle wrapped in a spiral muscular layer, and an undulating flask-shaped lemnisci, as well as double para-receptacle structures. Heterosentis mongcai n. sp. (Arhythmacanthidae), from Acreichthys sp., has a small fusiform trunk with an unarmed cone and anterior trunk spines, and a proboscis with two circles of rooted apical hooks and 3–4 circles of rooted posterior spines as well as a para-receptacle-like structure at the posterior end. The poorly known Filisoma indicum Van Cleave, 1928 is fully described and illustrated for the first time. Acanthocephalus parallelcementglandatus n. sp. (Echinorhynchidae), from Clarias batrachus, is distinguished from other species of Acanthocephalus by its small fusiform trunk and parallel tubular cement glands. Pseudoacanthocephalus coniformis n. sp. (Echinorhynchidae), from Hylarana sp., is distinguished from other species by having an anterior trunk collar and staggered prominent filiform cement glands, among other features. Cathayacanthus spinitruncatus n. sp. (Rhadinorhynchidae), from Leiognathus equulus, is distinguished from the only two known species of the genus by having a very long and slender proboscis with more than 50 hooks per row and a totally spined trunk. The generic diagnosis of Cathayacanthus Golvan, 1969 is emended. Rhadinorhynchus johnstoni Golvan, 1969 (Rhadinorhynchidae) perfectly fits the only complete description of that species from the Fiji Islands. PMID:25331738

Assessment of body-powered upper limb prostheses by able-bodied subjects, using the Box and Blocks Test and the Nine-Hole Peg Test.

PubMed

Haverkate, Liz; Smit, Gerwin; Plettenburg, Dick H

2016-02-01

The functional performance of currently available body-powered prostheses is unknown. The goal of this study was to objectively assess and compare the functional performance of three commonly used body-powered upper limb terminal devices. Experimental trial. A total of 21 able-bodied subjects (n = 21, age = 22 ± 2) tested three different terminal devices: TRS voluntary closing Hook Grip 2S, Otto Bock voluntary opening hand and Hosmer Model 5XA hook, using a prosthesis simulator. All subjects used each terminal device nine times in two functional tests: the Nine-Hole Peg Test and the Box and Blocks Test. Significant differences were found between the different terminal devices and their scores on the Nine-Hole Peg Test and the Box and Blocks Test. The Hosmer hook scored best in both tests. The TRS Hook Grip 2S scored second best. The Otto Bock hand showed the lowest scores. This study is a first step in the comparison of functional performances of body-powered prostheses. The data can be used as a reference value, to assess the performance of a terminal device or an amputee. The measured scores enable the comparison of the performance of a prosthesis user and his or her terminal device relative to standard scores. © The International Society for Prosthetics and Orthotics 2014.

A comparison of residual smear layer and erosion following different endodontic irrigation protocols tested under clinical and laboratory conditions.

PubMed

Cehreli, Zafer C; Uyanik, M Ozgur; Nagas, Emre; Tuncel, Behram; Er, Nuray; Comert, Fugen Dagli

2013-09-01

To compare the smear layer removal efficacy and erosive effects of different irrigation protocols under clinical and laboratory conditions. Mandibular third molars (n = 32) of 30-45 year-old patients were instrumented with rotary files and were randomly assigned to one of the following groups for final irrigation: (1) 5.25% NaOCl; (2) 17% EDTA; and (3) BioPure MTAD. Thereafter, the teeth were immediately extracted and processed for micromorphological investigation. In vitro specimen pairs were prepared by repeating the clinical experiments on freshly-extracted mandibular third molars. To compare open and closed systems, laboratory experiments were repeated on 32 additional teeth with enlarged apical foramen. The cleanliness of the root canals and the extent of erosion were assessed by environmental scanning electron microscopy. Specimens prepared under clinical and laboratory conditions had similar cleanliness and erosion scores (p > 0.05). Under both conditions, the tested solutions were more effective in removing the smear layer in the coronal and middle regions than in the apical one. Comparison of closed and open systems showed similar levels of cleanliness and erosion in all regions (p > 0.05), with the exception of 17% EDTA showing significantly higher levels of cleanliness and erosion in the apical third of open-end specimens. Based on clinical correlates of in vitro root canal cleanliness and erosion, laboratory testing of root canal irrigants on extracted teeth with closed apices can serve as a reliable method to simulate the clinical condition. EDTA was the most effective final irrigation solution in removing the smear layer at the expense of yielding the greatest erosive effect.

Purinergic P2Y receptors in airway epithelia: from ion transport to immune functions.

PubMed

Hao, Yuan; Ko, Wing-hung

2014-02-25

The regulated transport of salt and water is essential to the integrated function of many organ systems, including the respiratory, reproductive, and digestive tracts. Airway epithelial fluid secretion is a passive process that is driven by osmotic forces, which are generated by ion transport. The main determinant of a luminally-directed osmotic gradient is the mucosal transport of chloride ions (Cl(-)) into the lumen. As with many epithelial cells, a number of classic signal transduction cascades are involved in the regulation of ion transport. There are two well-known intracellular signaling systems: an increase in intracellular Ca(2+) concentration ([Ca(2+)]i) and an increase in the rate of synthesis of cyclic nucleotides, such as cyclic adenosine monophosphate (cAMP). Therefore, Cl(-) secretion is primarily activated via the opening of apical Ca(2+)- or cAMP-dependent Cl(-) channels at the apical membrane. The opening of basolateral Ca(2+)- or cAMP-activated K(+) channels, which hyperpolarizes the cell to maintain the driving force for Cl(-) exit through apical Cl(-) channels that are constitutively open, is also important in regulating transepithelial ion transport. P2Y receptors are expressed in the apical and/or basolateral membranes of virtually all polarized epithelia to control the transport of fluid and electrolytes. Human airway epithelial cells express multiple nucleotide receptors. Extracellular nucleotides, such as UTP and ATP, are calcium-mobilizing secretagogues. They are released into the extracellular space from airway epithelial cells and act on the same cell in an autocrine fashion to stimulate transepithelial ion transport. In addition, recent data support the role of P2Y receptors in releasing inflammatory cytokines in the bronchial epithelium and other immune cells.

Clavicle hook plate fixation for distal-third clavicle fracture (Neer type II): comparison of clinical and radiologic outcomes between Neer types IIA and IIB.

PubMed

Lee, Wonyong; Choi, Chong-Hyuk; Choi, Yun-Rak; Lim, Kyung-Han; Chun, Yong-Min

2017-07-01

The purpose of this study was to investigate clinical and radiologic outcomes of clavicle hook plate fixation for distal-third clavicle fracture (Neer type II) and to compare the clinical and radiologic outcomes and complications between Neer type IIA and type IIB. We retrospectively reviewed 35 patients who underwent open reduction and internal fixation with AO hook locking compression plate (LCP) for distal clavicle fracture, including 13 patients with Neer type IIA and 22 patients with type IIB. Visual analog scale pain score, shoulder scores (subjective shoulder value, University of California-Los Angeles shoulder score, American Shoulder and Elbow Surgeons score), and active range of motion were evaluated to determine clinical outcome. Coracoclavicular distance was measured, and that of the injured side at last follow-up was compared with that of the uninjured side to evaluate radiologic outcomes. AO hook LCP fixation for distal-third clavicle fracture (Neer type II) produced satisfactory radiologic outcomes, including high union rates (100%) and coracoclavicular distance maintenance, as well as satisfactory clinical outcomes, including visual analog scale score for pain, shoulder scores (subjective shoulder value, University of California-Los Angeles shoulder score, American Shoulder and Elbow Surgeons score), and active range of motion. There were no significant differences between Neer type IIA and type IIB. With regard to complications, 22.9% of patients experienced shoulder stiffness and 17.1% had subacromial erosion; however, there were no significant differences between the 2 groups. The AO hook LCP is a suitable choice for Neer type IIA and type IIB distal-third clavicle fracture fixation. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

The influence of hook type, angler experience, and fish size on injury rates and the duration of capture in an Alaskan catch-and-release rainbow trout fishery

USGS Publications Warehouse

Meka, Julie M.

2004-01-01

Owing to concerns about the high incidence of past hooking injuries in Alagnak River rainbow trout Oncorhynchus mykiss, fish were captured with spin- and fly-fishing gear with barbed and barbless circle and "J" hooks to determine gear types contributing to injury. Landing and hook removal times were measured for a portion of fish captured, and the anatomical hooking location, hooking scar locations, bleeding intensity, angler experience, and fish size were recorded for all captured fish. Approximately 62% of fish captured experienced at least one new hooking injury, and 29% of fish had at least one past hooking injury. Small fish sustained higher new injury and bleeding rates, but large fish had higher past injury rates. Injury rates were higher for barbed J hooks, barbed J hooks took longer to remove, and fish caught by spin-fishing were injured more frequently than fish caught by fly-fishing. Fewer fly-fishing-caught fish were injured using circle hooks, and circle hooks tended to hook fish in only one location, generally in the jaw. Barbed J hooks were more efficient at landing fish, and J hooks were more efficient at landing fish than circle hooks. Novice anglers injured proportionally more fish than experienced anglers, primarily during hook removal. Landing time was positively correlated with fish size, and experienced anglers took longer to land fish than novices because they captured larger fish. These results suggest that a reduction in hooking injuries may be achieved by using circle hooks as an alternative to J hooks and barbless J hooks to reduce injury and handling time, yet catch efficiency for both methods would be reduced. Although fish captured with barbless J hooks and circle hooks had fewer injuries, it is important to note that each hook type also caused significant injury, and angler education is recommended to promote proper hook removal techniques.

Performance of barbed and barbless hooks in a marine recreational fishery

USGS Publications Warehouse

Schaeffer, Jeffrey S.; Hoffman, Elizabeth M.

2002-01-01

We used an angling study to examine catch per unit effort (CPUE), bait loss, and total landings by anglers fishing with natural bait on barbed and barbless hooks in a nearshore marine sport fishery located in the Gulf of Mexico near St. Petersburg, Florida. Anglers fished half the day with a barbed hook and half the day with a barbless hook. We also recorded anatomical hook placement, severity of injury or bleeding, and hook extraction times for each landed fish. Bait loss, CPUE, and mean length of catch did not differ between gears, but anglers landed 22% more fish with barbed hooks. Loss of hooked fish was significantly higher with barbless hooks, and efficiency appeared to vary among species. Mean unhooking times were significantly shorter with barbless hooks. Anatomical hook placement did not differ between gears and most fish were hooked in the jaws. Bleeding did not differ between gears because bleeding was influenced strongly by hook placement, but barbless hooks reduced unhooking injuries. In this fishery, barbless hooks probably did not reduce hooking mortality and conferred only slight benefits at the expense of reduced catches.

Comparison of torsional stability of 2 types of split crimpable surgical hooks with soldered brass surgical hooks.

PubMed

O'Bannon, Shawn P; Dunn, William J; Lenk, Jason S

2006-10-01

The purpose of this in-vitro study was to compare the torsional stability of split crimpable surgical hooks and soldered brass surgical hooks on a rectangular stabilizing archwire. Coated split crimpable hooks (Never-Slip Grip, TP Orthodontics, LaPorte, Ind), ribbed crimpable hooks (TP Orthodontics), and .032-in brass soldered hooks/notched electrodes (Ormco/Sybron Dental Specialties, Orange, Calif) were attached to a 0.019 x 0.025-in stainless steel archwire. The archwire/hook attachment assembly was secured into a dual contact jig and statically mounted to the base of a universal testing machine. The hooks were engaged by a wire loop attached to the upper load cell of the machine, which pulled the wire until the hook was torsionally displaced from the archwire. The mean forces, measured in newtons (N), required to dislodge the hooks were as follows: soldered brass surgical hooks (51.3 +/- 5.2 N), coated split crimpable hooks (49.9 +/- 6.6 N), and ribbed split crimpable hooks (31.3 +/- 5.4 N). Data were analyzed with 1-way ANOVA and Tukey HSD post-hoc tests at alpha = .05. Ribbed split crimpable hooks provided significantly less resistance to torsional displacement than the other types of hooks (P <001). There was no difference between coated split crimpable hooks and soldered brass surgical hooks (P >05). Under the conditions of this study, the results suggest that soldered brass surgical hooks and coated split crimpable hook attachments provide more stability to torsional dislodgement from a rectangular stabilizing archwire than ribbed split crimpable hooks.

Comparison of debris extruded apically and working time used by ProTaper Universal rotary and ProTaper retreatment system during gutta-percha removal

PubMed Central

UEZU, Mary Kinue Nakamune; BRITTO, Maria Leticia Borges; NABESHIMA, Cleber K.; PALLOTTA, Raul Capp

2010-01-01

Objective The aim of this study was to evaluate the in vitro action of ProTaper retreatment files and ProTaper Universal in the retreatment of mandibular premolars. Material and methods The amount of debris extruded apically was measured and the time to reach the working length and to complete the removal of gutta-percha was observed. Thirty teeth had their canals prepared using ProTaper Universal files and were obturated by the single cone technique. The teeth were then stored at 37ºC in a humid environment for 7 days. During the use of the rotary instruments for root canal filling removal, the apical portions of the teeth were attached to the open end of a resin tube to collect the apically extruded debris. Results ProTaper Universal files were significantly faster (p=0.0011) than the ProTaper retreatment files to perform gutta-percha removal, but no significant difference was found between the files regarding the time to reach the working length or the amount of apical extrusion. Conclusions ProTaper Universal rotary had better results for endodontic retreatment, and both techniques promote similar apical extrusion of debris. PMID:21308282

Comparative Analysis of Calcium Silicate-based Root Filling Materials Using an Open Apex Model.

PubMed

Tran, Dennis; He, Jianing; Glickman, Gerald N; Woodmansey, Karl F

2016-04-01

Many new calcium silicate-based root filling materials have emerged in the market; however, their performance in the orthograde obturation of an open apex has not been evaluated. The purpose of this study was to compare the marginal adaptation of ProRoot MTA (Dentsply Tulsa Dental, Tulsa, OK), NeoMTA Plus (Avalon Biomed Inc, Bradenton, FL), and Endosequence BC RRM-Fast Set Putty (BC RRM-FS; Brasseler USA, Savannah, GA) after orthograde placement in roots with open apices. Palatal roots of maxillary molars were instrumented to create divergent open apices and divided into 4 groups for orthograde obturation: ProRoot MTA, NeoMTA Plus, BC RRM-FS, and BC RRM-FS + BC Sealer. Using a scanning electron microscope, the quality of material adaptation at the anatomic apex was evaluated by 5 blinded examiners; 3 mm of the root end was sectioned, and gap distance was measured at the material-dentin interface. Statistical analyses were performed using the Kruskal-Wallis test. There were no significant differences in marginal adaptation among the 4 groups at the level of the anatomic apex (P = .175). BC RRM-FS + BC Sealer had a significantly smaller gap size after 3-mm root end resection compared with the other 3 groups (P < .01). No differences were observed among the other 3 materials. All materials showed comparable marginal adaptation at the anatomic apex when used for orthograde obturation of open apices. Application of BC Sealer before the delivery of BC RRM-FS Putty enhanced the quality of adaptation coronal to the apex. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

[Ultrastructure and cytochemistry of the pellicle and apical complexes of the kinete of Babesia bigemina and Babesia ovis in the hemolymph and oavry of the tick].

PubMed

Weber, G

1980-02-01

The term kinete is used in this paper for the cigar-shaped, motile development stages (VERMICULE") OF Babesia occurring intra- and extracellularly in hemolymph and overy (including oocytes) of vectors, hard ticks (Ixodoidea). The structure of, and cytochemical activities of hydrolases (acid phosphatase, nonspecific esterase) in the pellicle and the apical complex was studied at the fine-structural level in kinetes of Babesia bigemina Smith & Kilborne, in hemolympho of female Boophilus microplus Canestrini. The cytochemistry of acid hydrolases was studied also in kinetes of Babesia ovis (Babès) Starcovici, in hemolymph and ovary of Rhipicephalus bursa Canestrini & Fanzago. The pellicle of the B. bigemina kinetes is composted of 3 membranes (pellicular complex): an outer membrane, approximately 8 nm thick (the plasmalemma) and 2 innder ones, each approximately nm thick, lying closely together. The outer membrane appears to be covered by a structureless coat, 3 nm thick. The space between the inner double membrane and the plasmalemma is 7.5 nm. The whole pellicular complex is 30 nm in diameter. The 2 inner pellicular membranes appear to be derived from the endoplasmic reticulum (ER) for the following reasons: (a) a layer of hydrolase-active material is enclosed by these membranes; (b) in the spheroid parasite stages which transform from kinetes inside hemocytes, the inner double membrane is apparently replaced by an ER cisterna; (c) the thickness of each of the inner pellicular membranes is approximately the same as that of the ER membrane. There are circular openings in the pellicular double membrane with average diameters of 100 nm; despite some similarity to micropores, they have a specific structure. The term Intrapellikularfenster (IPF) (intrapellicular windows) or pseudomicropores is proposed for these pellicular differentiations. The margin of an IPF is formed by the 2 inner membranes folding into each other; cytoplasmic, electron-dense material is accumulated alongside this edge. Unlike that of micropores, the plasmalemma of the IPF is not invaginated. The IPF appears as a single, dark ring in tangential sections. At times, rhoptry-like bodies are associated with the openings. The function of the IPF is not known. An intrapellicular opening similar to the IPF, although wider, is present at the apex of the parasite. Its margin coincides with the inners edge of the apical ring. Typical subpellicular microtubuli were not observed in the Babesia kinetes. The apical complex of the B. bigemina kinetes consists of an Apikalschirm (apical umbrella), a crown of microtubuli beneath it, and rhoptries: micronemes are also present in large numbers. The Apikalschirm is located beneath the pellicle of the apical pole of the parasite. It is a wheel-like structure composed of spokes radiating from a wide, hub=like central ring (apical ring). It should be stressed that the apical ring is not identical with the polar ring described as an integral part of the pellicular complex in other Apicomplexa...

Biomechanical analysis of clavicle hook plate implantation with different hook angles in the acromioclavicular joint.

PubMed

Hung, Li-Kun; Su, Kuo-Chih; Lu, Wen-Hsien; Lee, Cheng-Hung

2017-08-01

A clavicle hook plate is a simple and effective method for treating acromioclavicular dislocation and distal clavicle fractures. However, subacromial osteolysis and peri-implant fractures are complicated for surgeons to manage. This study uses finite element analysis (FEA) to investigate the post-implantation biomechanics of clavicle hook plates with different hook angles. This FEA study constructed a model with a clavicle, acromion, clavicle hook plate, and screws to simulate the implantation of clavicle hook plates at different hook angles (90°, 95°, 100°, 105°, and 110°) for treating acromioclavicular joint dislocations. This study investigated the biomechanics of the acromion, clavicle, hook plate, and screws. A smaller hook angle increases the stress on the middle third of the clavicle. A larger hook angle increases the force exerted by the clavicle hook plate on the acromion. The screw at the most medial position on the plate generated the highest stress. The highest stress on the implanted clavicle hook plate was on the turning corner of the hook. A clavicle hook plate with different hook angles may induce different biomechanical behaviors in the clavicle and acromion. Orthopedic surgeons must select a suitable clavicle hook plate based on the anatomical structure of each patient.

46 CFR 160.002-3 - Materials.

Code of Federal Regulations, 2012 CFR

2012-10-01

... warp and 70 pounds in the filling. If it is proposed to treat the fabric with a fire-retardant... of the type specified in paragraph (j) of this section. (g) Dee rings and snap hook. The dee rings...-resistant material. Dee ring ends shall be welded to form a continuous ring. The webbing opening of the snap...

46 CFR 160.005-3 - Materials.

Code of Federal Regulations, 2014 CFR

2014-10-01

... and 70 pounds in the filling. If it is proposed to treat the fabric with a fire-retardant substance... of the type specified in paragraph (j) of this section. (g) Dee rings and snap hook. The dee rings...-resistant material. Dee ring ends shall be welded to form a continuous ring. The webbing opening of the snap...

46 CFR 160.002-3 - Materials.

Code of Federal Regulations, 2013 CFR

2013-10-01

... warp and 70 pounds in the filling. If it is proposed to treat the fabric with a fire-retardant... of the type specified in paragraph (j) of this section. (g) Dee rings and snap hook. The dee rings...-resistant material. Dee ring ends shall be welded to form a continuous ring. The webbing opening of the snap...

46 CFR 160.002-3 - Materials.

Code of Federal Regulations, 2014 CFR

2014-10-01

... warp and 70 pounds in the filling. If it is proposed to treat the fabric with a fire-retardant... of the type specified in paragraph (j) of this section. (g) Dee rings and snap hook. The dee rings...-resistant material. Dee ring ends shall be welded to form a continuous ring. The webbing opening of the snap...

46 CFR 160.005-3 - Materials.

Code of Federal Regulations, 2012 CFR

2012-10-01

... and 70 pounds in the filling. If it is proposed to treat the fabric with a fire-retardant substance... of the type specified in paragraph (j) of this section. (g) Dee rings and snap hook. The dee rings...-resistant material. Dee ring ends shall be welded to form a continuous ring. The webbing opening of the snap...

46 CFR 160.005-3 - Materials.

Code of Federal Regulations, 2013 CFR

2013-10-01

... and 70 pounds in the filling. If it is proposed to treat the fabric with a fire-retardant substance... of the type specified in paragraph (j) of this section. (g) Dee rings and snap hook. The dee rings...-resistant material. Dee ring ends shall be welded to form a continuous ring. The webbing opening of the snap...

50 CFR 665.245 - Gear restrictions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Gear restrictions. (a) Permit Area 1. (1) Lobsters may be taken only with lobster traps or by hand. Lobsters may not be taken by means of poisons, drugs, other chemicals, spears, nets, hook, or explosives. (2) The smallest opening of an entry way of any lobster trap may not allow any sphere or cylinder...

Automation Hooks Architecture Trade Study for Flexible Test Orchestration

NASA Technical Reports Server (NTRS)

Lansdowne, Chatwin A.; Maclean, John R.; Graffagnino, Frank J.; McCartney, Patrick A.

2010-01-01

We describe the conclusions of a technology and communities survey supported by concurrent and follow-on proof-of-concept prototyping to evaluate feasibility of defining a durable, versatile, reliable, visible software interface to support strategic modularization of test software development. The objective is that test sets and support software with diverse origins, ages, and abilities can be reliably integrated into test configurations that assemble and tear down and reassemble with scalable complexity in order to conduct both parametric tests and monitored trial runs. The resulting approach is based on integration of three recognized technologies that are currently gaining acceptance within the test industry and when combined provide a simple, open and scalable test orchestration architecture that addresses the objectives of the Automation Hooks task. The technologies are automated discovery using multicast DNS Zero Configuration Networking (zeroconf), commanding and data retrieval using resource-oriented Restful Web Services, and XML data transfer formats based on Automatic Test Markup Language (ATML). This open-source standards-based approach provides direct integration with existing commercial off-the-shelf (COTS) analysis software tools.

Survival of foul-hooked largemouth bass (Micropterus salmoides)

USGS Publications Warehouse

Pope, K.L.; Wilde, G.R.

2010-01-01

We conducted a field experiment to determine the survival rate of foul-hooked (hooked external to the oral cavity) largemouth bass (Micropterus salmoides) caught and released by recreational anglers. Of 42 largemouth bass caught with hard-plastic baits containing three treble hooks, 15 were hooked only within the mouth and 27 had at least one hook penetrating the external surface of the fish (i.e., foul-hooked). There was no difference in survival of mouth-hooked (100%), foul-hooked (100%), or control (100%) largemouth bass.

Nickel Superoxide Dismutase: Structural and Functional Roles of His1 and its H-bonding Network

PubMed Central

Ryan, Kelly C.; Guce, Abigail I.; Johnson, Olivia E.; Brunold, Thomas C.; Cabelli, Diane E.; Garman, Scott C.; Maroney, Michael J.

2015-01-01

Crystal structures of nickel-dependent superoxide dismutases (NiSODs) reveal the presence of a H-bonding network formed between the N-H of the apical imidazole ligand from His1 and the Glu17 carboxylate from a neighboring subunit in the hexameric enzyme. This interaction is supported by another intra-subunit H-bond between Glu17 and Arg47. In this study, four mutant NiSOD proteins were produced to experimentally evaluate the roles of this H-bonding network, and compare the results with prior predictions from DFT calculations. H1A-NiSOD, which lacks the apical ligand entirely, was crystallographically characterized and reveals that in the absence of the Glu17-His1 H-bond, the active site is disordered. Subsequent characterization using X-ray absorption spectroscopy (XAS) shows that Ni(II) is bound in the expected N2S2 planar coordination site. Despite these structural perturbations, the H1A-NiSOD variant is an active catalyst with 4% of WT-NiSOD activity. Three other mutations were designed to preserve the apical imidazole ligand, but perturb the H-bonding network: R47A-NiSOD, lacks the intra-molecular H-bonding interaction, E17R/R47A-NiSOD, which retains the intra-molecular H-bond, but lacks the inter-molecular Glu17-His1 H-bond, and E17A/R47A-NiSOD, which lacks both H-bonding interactions. These variants were characterized by a combination of techniques including XAS characterization of the nickel site structure, kinetic studies employing pulse-radiolytic production of superoxide, and EPR and chemical probes of the redox activity. The results indicate that in addition to the roles in redox tuning suggested by the computational models, the Glu17-His1 H-bond plays an important structural role in the formation of the Ni-hook motif that is a critical feature of the active site. PMID:25580509

Pulp Revascularization on Permanent Teeth with Open Apices in a Middle-aged Patient.

PubMed

Wang, Yu; Zhu, Xiaofei; Zhang, Chengfei

2015-09-01

Pulp revascularization is a promising procedure for the treatment of adolescents' immature permanent teeth with necrotic pulp and/or apical periodontitis. However, the ability to successfully perform pulp revascularization in a middle-aged patient remains unclear. A 39-year-old woman was referred for treatment of teeth #20 and #29 with necrotic pulp, extensive periapical radiolucencies, and incomplete apices. Pulp revascularization procedures were attempted, including root canal debridement, triple antibiotic paste medication, and platelet-rich plasma transplantation to act as a scaffold. Periapical radiographic and cone-beam computed tomographic examinations were used to review the changes in the apical lesions and root apex configuration. The patient remained asymptomatic throughout the 30-month follow-up. Periapical radiographic examination revealed no change in the apical lesions of either tooth at 8 months. The periapical radiolucency disappeared on tooth #20 and significantly decreased on tooth #29 by the 30-month follow-up, findings that were also confirmed by cone-beam computed tomographic imaging. No evidence of root lengthening or thickening was observed. Successful revascularization was achieved in a middle-aged patient's teeth. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Tongue-Tied: The Lives of Multilingual Children in Public Education

ERIC Educational Resources Information Center

Santa Ana, Otto

2004-01-01

Tongue-Tied is an anthology that gives voice to millions of people who, on a daily basis, are denied the opportunity to speak in their own language. First-person accounts by Amy Tan, Sherman Alexie, Bell Hooks, Richard Rodriguez, Maxine Hong Kingston, and many other authors open windows into the lives of linguistic minority students and their…

Working without a Safety Net

ERIC Educational Resources Information Center

Foster, Colin

2012-01-01

A science teacher has the advantage of hooking learners with all their senses: flashes, bangs and smells. The science labs are something that many learners at the start of secondary school (high school) are eager to explore, and when there is an open day at school it feels unfair that the mathematics department has to try to compete for excitement…

A new genus and two new nematode species (Drilonematoidea: Ungellidae: Synoecneminae) parasitic in two morphs of Drawida ghilarovi Gates, endemic earthworm from the Russian Far East.

PubMed

Ivanova, Elena S; Ganin, Gennadiy N; Spiridonov, Sergei E

2014-03-01

Drasico n. g. is erected to accommodate two new species of nematode, Drasico nemoralis n. sp. and D. paludigenus n. sp., recovered from coelomic cavities of Drawida ghilarovi Gates, endemic earthworms of the Russian Far East. The new genus is characterised by the following unique for the Synoecneminae characters: apical portion of the head attenuated, cephalic hooks displaced to the base of attenuated portion, amphids displaced posterior to cephalic hooks, excretory duct short and weak, males possessing several genital papilliform sensilla. The new species are differentiated by the size, number and disposition of the male genital sensilla (larger and more numerous in D. nemoralis n. sp.); the body shape of females (with thinner neck and wider mid-body in D. paludigenus n. sp.) and the ovarian tube arranged in transversal folds in D. paludigenus (vs longitudinal folds in D. nemoralis n. sp.). Nucleotide sequences of D2-D3 expansion segment of 28S rDNA for the two new species differed at 13 positions. Phylogenetic analysis revealed close relationships of Drasico n. g. with species of Siconema Timm, 1966. The host species was represented by two morphs (blue-grey forest and tar-black meadow-swamp morph) with intraspecific divergence of 16-17% for cytochrome c oxidase subunit 1 (COI) gene, and each host morph was found infected by a different nematode species. A co-infection with the plectid nematode Creagrocercus drawidae Ivanova & Spiridonov, 2011 was recorded together with D. nemoralis n. sp. in the blue-grey forest morph.

Acanthocephalans from fishes and amphibians in Vietnam, with descriptions of five new species.

PubMed

Amin, Omar Mohamed; Heckmann, Richard Anderson; Van Ha, Nguyen

2014-01-01

Eight species of acanthocephalans are reported, and five are new. Specimens of Neoechinorhynchus (Hebesoma) manubrianus Amin, Ha & Ha, 2011 were similar to the original description. Neoechinorhynchus (Hebesoma) spiramuscularis n. sp. (Neoechinorhynchidae), from Xenocypris davidi, has a unique proboscis receptacle wrapped in a spiral muscular layer, and an undulating flask-shaped lemnisci, as well as double para-receptacle structures. Heterosentis mongcai n. sp. (Arhythmacanthidae), from Acreichthys sp., has a small fusiform trunk with an unarmed cone and anterior trunk spines, and a proboscis with two circles of rooted apical hooks and 3-4 circles of rooted posterior spines as well as a para-receptacle-like structure at the posterior end. The poorly known Filisoma indicum Van Cleave, 1928 is fully described and illustrated for the first time. Acanthocephalus parallelcementglandatus n. sp. (Echinorhynchidae), from Clarias batrachus, is distinguished from other species of Acanthocephalus by its small fusiform trunk and parallel tubular cement glands. Pseudoacanthocephalus coniformis n. sp. (Echinorhynchidae), from Hylarana sp., is distinguished from other species by having an anterior trunk collar and staggered prominent filiform cement glands, among other features. Cathayacanthus spinitruncatus n. sp. (Rhadinorhynchidae), from Leiognathus equulus, is distinguished from the only two known species of the genus by having a very long and slender proboscis with more than 50 hooks per row and a totally spined trunk. The generic diagnosis of Cathayacanthus Golvan, 1969 is emended. Rhadinorhynchus johnstoni Golvan, 1969 (Rhadinorhynchidae) perfectly fits the only complete description of that species from the Fiji Islands. © O.M. Amin et al., published by EDP Sciences, 2014.

Stress analyses of B-52 pylon hooks

NASA Technical Reports Server (NTRS)

Ko, W. L.; Schuster, L. S.

1985-01-01

The NASTRAN finite element computer program was used in the two dimensional stress analysis of B-52 carrier aircraft pylon hooks: (1) old rear hook (which failed), (2) new rear hook (improved geometry), (3) new DAST rear hook (derated geometry), and (4) front hook. NASTRAN model meshes were generated by the aid of PATRAN-G computer program. Brittle limit loads for all the four hooks were established. The critical stress level calculated from NASTRAN agrees reasonably well with the values predicted from the fracture mechanics for the failed old rear hook.

Lunar crane hook

NASA Technical Reports Server (NTRS)

Cash, John Wilson, III; Cone, Alan E.; Garolera, Frank J.; German, David; Lindabury, David Peter; Luckado, Marshall Cleveland; Murphey, Craig; Rowell, John Bryan; Wilkinson, Brad

1988-01-01

The base and ball hook system is an attachment that is designed to be used on the lunar surface as an improved alternative to the common crane hook and eye system. The design proposed uses an omni-directional ball hook and base to overcome the design problems associated with a conventional crane hook. The base and ball hook is not sensitive to cable twist which would render a robotic lunar crane useless since there is little atmospheric resistance to dampen the motion of an oscillating member. The symmetric characteristics of the ball hook and base eliminates manual placement of the ball hook into the base; commonly associated with the typical hook and eye stem. The major advantage of the base and ball hook system is it's ease of couple and uncouple modes that are advantages during unmanned robotic lunar missions.

Dynamic change in left ventricular apical back rotation: a marker of diastolic suction with exercise.

PubMed

Hong, Sung-Jin; Shim, Chi Young; Kim, Darae; Cho, In-Jeong; Hong, Geu-Ru; Moon, Sun-Ha; Lee, Hyun-Jin; Lee, Jin-Kyung; Choi, Donghoon; Jang, Yangsoo; Ha, Jong-Won

2018-01-01

We hypothesized that the absence of a decrease in minimal left ventricular (LV) pressure during exercise would be associated with impaired LV apical back rotation during exercise. A total of 21 patients (59 ± 10 years) underwent invasive LV pressure measurements and simultaneous echocardiography at rest and during submaximal supine bicycle exercise. Patients were classified according to the changes in minimal LV pressure from rest to maximal exercise (Δminimal LVP); Group 1 (n = 8) had a decrease in minimal LV pressure with exercise, whereas Group 2 (n = 13) had an increase in minimal LV pressure. LV apical back-rotation parameters by speckle-tracking echocardiography at rest and during 50 W of exercise were compared. At rest, there were no differences in LV pressure and echocardiographic parameters between groups. However, at 50 W of exercise, Group 2 had higher LV early and end-diastolic pressures and a prolonged time constant of LV relaxation. In Group 2, e' velocity was lower and E/e' was higher. Apical back rotation at the mitral valve opening (MVO) was reduced and minimal apical back-rotation velocity was lower in Group 2. Δminimal LVP significantly correlated with apical back rotation at MVO (r = -0.77, P = 0.009) and minimal apical back-rotation velocity at 50 W (r = 0.69, P = 0.028). The lack of decrease in minimal LV pressure during exercise, a manifestation of impaired LV suction in early diastole, is linked closely with impaired LV apical back rotation during exercise. Dynamic changes in LV apical back rotation during exercise can be used as a non-invasive parameter of diastolic suction during exercise. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions, please email: journals.permissions@oup.com.

Modeling the hook depth distribution of pelagic longlining in the equatorial area of Indian Ocean

NASA Astrophysics Data System (ADS)

Song, Liming; Li, Jie; Gao, Panfeng; Zhou, Ji; Xu, Liuxiong

2012-12-01

A survey was conducted in the equatorial area of Indian Ocean for a better understanding of the dynamics of hook depth distribution of pelagic longline fishery. We determined the relationship between hook depth and vertical shear of current coefficiency, wind speed, hook position code, sine of wind angle, sine of angle of attack and weight of messenger weight. We identified the hook depth models by the analysis of covariance with a general linear model. The results showed that the wind effect on the hook depth can be ignored from October to November in the survey area; the surface current effect on the hook depth can be ignored; the equatorial undercurrent is the key factor for the hook depth in Indian Ocean; and there is a negative correlation between the hook depth and vertical shear of current and angle of attack. It was also found that the deeper the hook was set, the higher hook depth shoaling was. The proposed model improves the accuracy of the prediction of hook depth, which can be used to estimate the vertical distribution of pelagic fish in water column.

A general methodology for inverse estimation of the elastic and anelastic properties of anisotropic open-cell porous materials—with application to a melamine foam

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cuenca, Jacques, E-mail: jcuenca@kth.se; Van der Kelen, Christophe; Göransson, Peter

2014-02-28

This paper proposes an inverse estimation method for the characterisation of the elastic and anelastic properties of the frame of anisotropic open-cell foams used for sound absorption. A model of viscoelasticity based on a fractional differential constitutive equation is used, leading to an augmented Hooke's law in the frequency domain, where the elastic and anelastic phenomena appear as distinctive terms in the stiffness matrix. The parameters of the model are nine orthotropic elastic moduli, three angles of orientation of the material principal directions and three parameters governing the anelastic frequency dependence. The inverse estimation consists in numerically fitting the modelmore » on a set of transfer functions extracted from a sample of material. The setup uses a seismic-mass measurement repeated in the three directions of space and is placed in a vacuum chamber in order to remove the air from the pores of the sample. The method allows to reconstruct the full frequency-dependent complex stiffness matrix of the frame of an anisotropic open-cell foam and in particular it provides the frequency of maximum energy dissipation by viscoelastic effects. The characterisation of a melamine foam sample is performed and the relation between the fractional-derivative model and other types of parameterisations of the augmented Hooke's law is discussed.« less

A general methodology for inverse estimation of the elastic and anelastic properties of anisotropic open-cell porous materials—with application to a melamine foam

NASA Astrophysics Data System (ADS)

Cuenca, Jacques; Van der Kelen, Christophe; Göransson, Peter

2014-02-01

This paper proposes an inverse estimation method for the characterisation of the elastic and anelastic properties of the frame of anisotropic open-cell foams used for sound absorption. A model of viscoelasticity based on a fractional differential constitutive equation is used, leading to an augmented Hooke's law in the frequency domain, where the elastic and anelastic phenomena appear as distinctive terms in the stiffness matrix. The parameters of the model are nine orthotropic elastic moduli, three angles of orientation of the material principal directions and three parameters governing the anelastic frequency dependence. The inverse estimation consists in numerically fitting the model on a set of transfer functions extracted from a sample of material. The setup uses a seismic-mass measurement repeated in the three directions of space and is placed in a vacuum chamber in order to remove the air from the pores of the sample. The method allows to reconstruct the full frequency-dependent complex stiffness matrix of the frame of an anisotropic open-cell foam and in particular it provides the frequency of maximum energy dissipation by viscoelastic effects. The characterisation of a melamine foam sample is performed and the relation between the fractional-derivative model and other types of parameterisations of the augmented Hooke's law is discussed.

Separable fastening device

DOEpatents

Harvey, Andrew C.; Ribich, William A.; Marinaccio, Paul J.; Sawaf, Bernard E.

1987-12-01

A separable fastener system has a first separable member that includes a series of metal hook sheets disposed in stacked relation that defines an array of hook elements on its broad surface. Each hook sheet is a planar metal member of uniform thickness and has a body portion with a series of hook elements formed along one edge of the body. Each hook element includes a stem portion, a deflecting surface portion, and a latch portion. Metal spacer sheets are disposed between the hook sheets and may be varied in thickness and in number to control the density of the hook elements on the broad surface of the first fastener member. The hook and spacer sheets are secured together in stacked relation. A second fastener member has a surface of complementary engaging elements extending along its broad surface which are releasably interengageable with the hook elements of the first fastener member, the deflecting surfaces of the hook elements of the first fastener member tending to deflect hook engaging portions of the second fastener member and the latch portions of the hook elements of the first fastener member engaging portions of the second fastener member in fastening relation.

Absorbable Suture as an Apical Matrix in Single Visit Apexification with Mineral Trioxide Aggregate.

PubMed

Goyal, Ayush; Nikhil, Vineeta; Jha, Padmanabh

2016-01-01

Several procedures have been recommended to induce the root end barrier formation in teeth with open apices. Conventional treatment for such cases will require many appointments with an average duration of 12.9 months. During this period, the root canal is susceptible to reinfection from around the provisional restoration, which may promote apical periodontitis and arrest of apical repair. Mineral trioxide aggregate (MTA) has been successfully used for one visit apexification wherein the root canal can be obturated within 24 hours after placement of MTA. Using a matrix prior to the placement of MTA avoids its extrusion, reduces leakage in the sealing material, and allows favorable response of the periapical tissues. This report presents a case of apexification where an absorbable suture was used as an apical matrix. Use of an absorbable suture circumvents all the problems associated with other conventional materials. Conclusion . Placement of the matrix made from the suture material is predictable and is easily positioned at the apex and the length can be adjusted as required. 10-month follow-up of the case shows resorbed matrix and bone healing in the periapical region. The patient was asymptomatic during the whole follow-up period and tooth exhibited mobility within physiologic limits and was functioning normally.

Use an Interactive Whiteboard: Get a Handle on How This Technology Can Spice up the Classroom

ERIC Educational Resources Information Center

Branzburg, Jeffrey

2006-01-01

Interactive whiteboards are desirable peripherals these days. When hooked up to a computer, the whiteboard's screen becomes a "live" computer desktop, which can be tapped to pull down menus, highlight, and move or open files. Users can also circle relevant sections on the projected image, draw geometric figures, and underline. Then they can save…

46 CFR 160.048-4 - Construction and workmanship.

Code of Federal Regulations, 2012 CFR

2012-10-01

... provide buoyancy to aid a person in keeping afloat in the water. No hooks, snaps, or other means shall be... less than 5 ounces of kapok or 9 ounces of fibrous glass each; and the volume displacement of the... accordance with the method set forth in § 160.048-5(e)(1), except that the pad covers shall not be slit open...

By Hook or by MOOC: Lessons Learned and the Road Ahead

ERIC Educational Resources Information Center

Korsunsky, Boris; Li, Clara

2017-01-01

As online education has exploded in the past decade, the number of physics and physics-related massive open online courses (or MOOCs, to use the industry lingo) has grown substantially as well. Several such courses aim at high school students, especially those involved in the AP Physics program. One of us (BK) was involved in creating two such…

Role of the Dc domain of the bacterial hook protein FlgE in hook assembly and function

PubMed Central

Moriya, Nao; Minamino, Tohru; Ferris, Hedda U.; Morimoto, Yusuke V.; Ashihara, Masamichi; Kato, Takayuki; Namba, Keiichi

2013-01-01

The bacterial flagellar hook acts as a universal joint to smoothly transmit torque produced by the motor to the filament. The hook protein FlgE assembles into a 55 nm tubular structure with the help of the hook cap (FlgD). FlgE consists of four domains, D0, Dc, D1 and D2, arranged from the inner to the outer part of the tubular structure of the hook. The Dc domain contributes to the structural stability of the hook, but it is unclear how this Dc domain is responsible for the universal joint mechanism. Here, we carried out a deletion analysis of the FlgE Dc domain. FlgEΔ4/5 with deletion of residues 30 to 49 was not secreted into the culture media. FlgEΔ5 and FlgEΔ6 with deletions of residues 40 to 49 and 50 to 59, respectively, still formed hooks, allowing the export apparatus to export the hook-filament junction proteins FlgK and FlgL and flagellin FliC. However, these deletions inhibited the replacement of the FlgD hook cap by FlgK at the hook tip, thereby abolishing filament formation. Deletion of residues 50 to 59 significantly affected hook morphology. These results suggest that the Dc domain is responsible not only for hook assembly but also for FlgE export, the interaction with FlgK, and the polymorphic supercoiling mechanism of the hook. PMID:27493542

NPH4, a Conditional Modulator of Auxin-Dependent Differential Growth Responses in Arabidopsis1

PubMed Central

Stowe-Evans, Emily L.; Harper, Reneé M.; Motchoulski, Andrei V.; Liscum, Emmanuel

1998-01-01

Although sessile in nature, plants are able to use a number of mechanisms to modify their morphology in response to changing environmental conditions. Differential growth is one such mechanism. Despite its importance in plant development, little is known about the molecular events regulating the establishment of differential growth. Here we report analyses of the nph4 (nonphototropic hypocotyl) mutants of Arabidopsis that suggest that the NPH4 protein plays a central role in the modulation of auxin-dependent differential growth. Results from physiological studies demonstrate that NPH4 activity is conditionally required for a number of differential growth responses, including phototropism, gravitropism, phytochrome-dependent hypocotyl curvature, apical hook maintenance, and abaxial/adaxial leaf-blade expansion. The nph4 mutants exhibited auxin resistance and severely impaired auxin-dependent gene expression, indicating that the defects associated with differential growth likely arise because of altered auxin responsiveness. Moreover, the auxin signaling events mediating phototropism are genetically correlated with the abundance of the NPH4 protein. PMID:9847100

Hook1 inhibits malignancy and epithelial-mesenchymal transition in hepatocellular carcinoma.

PubMed

Sun, Xu; Zhang, Qi; Chen, Wei; Hu, Qida; Lou, Yu; Fu, Qi-Han; Zhang, Jing-Ying; Chen, Yi-Wen; Ye, Long-Yun; Wang, Yi; Xie, Shang-Zhi; Hu, Li-Qiang; Liang, Ting-Bo; Bai, Xue-Li

2017-07-01

Hook1 is a member of the hook family of coiled-coil proteins, which is recently found to be associated with malignant tumors. However, its biological function in hepatocellular carcinoma is yet unknown. Here, we evaluated the Hook1 levels in human hepatocellular carcinoma samples and matched peritumoral tissues by real-time polymerase chain reaction. Small interfering RNA knockdown and a transforming growth factor-β-induced epithelial-mesenchymal transition model were employed to investigate the biological effects of Hook1 in hepatocellular carcinoma. Our results indicated that Hook1 levels were significantly lower in hepatocellular carcinoma tissues than in the peritumoral tissues. In addition, Hook1 expression was significantly associated with hepatocellular carcinoma malignancy. Hook1 was downregulated after transforming growth factor-β-induced epithelial-mesenchymal transition. Moreover, Hook1 knockdown promoted epithelial-mesenchymal transition and attenuated the sensitivity of hepatocellular carcinoma cells to doxorubicin. In summary, our results indicate that downregulation of Hook1 plays a pivotal role in hepatocellular carcinoma progression via epithelial-mesenchymal transition. Hook1 may be used as a novel marker and therapeutic molecular target in hepatocellular carcinoma.

"Hooking up" among college students: demographic and psychosocial correlates.

PubMed

Owen, Jesse J; Rhoades, Galena K; Stanley, Scott M; Fincham, Frank D

2010-06-01

This study investigated 832 college students' experiences with hooking up, a term that refers to a range of physically intimate behavior (e.g., passionate kissing, oral sex, and intercourse) that occurs outside of a committed relationship. Specifically, we examined how five demographic variables (sex, ethnicity, parental income, parental divorce, and religiosity) and six psychosocial factors (e.g., attachment styles, alcohol use, psychological well-being, attitudes about hooking up, and perceptions of the family environment) related to whether individuals had hooked up in the past year. Results showed that similar proportions of men and women had hooked up but students of color were less likely to hook up than Caucasian students. More alcohol use, more favorable attitudes toward hooking up, and higher parental income were associated with a higher likelihood of having hooked up at least once in the past year. Positive, ambivalent, and negative emotional reactions to the hooking up experience(s) were also examined. Women were less likely to report that hooking up was a positive emotional experience than men. Young adults who reported negative and ambivalent emotional reactions to hooking up also reported lower psychological well-being and less favorable attitudes toward hooking up as compared to students who reported a positive hooking up experience. Based on these findings, suggestions for psychoeducational programming are offered. Additionally, directions for future research are provided.

Biomechanical analysis of acromioclavicular joint dislocation treated with clavicle hook plates in different lengths.

PubMed

Shih, Cheng-Min; Huang, Kui-Chou; Pan, Chien-Chou; Lee, Cheng-Hung; Su, Kuo-Chih

2015-11-01

Clavicle hook plates are frequently used in clinical orthopaedics to treat acromioclavicular joint dislocation. However, patients often exhibit acromion osteolysis and per-implant fracture after undergoing hook plate fixation. With the intent of avoiding future complications or fixation failure after clavicle hook plate fixation, we used finite element analysis (FEA) to investigate the biomechanics of clavicle hook plates of different materials and sizes when used in treating acromioclavicular joint dislocation. Using finite element analysis, this study constructed a model comprising four parts: clavicle, acromion, clavicle hook plate and screws, and used the model to simulate implanting different types of clavicle hook plates in patients with acromioclavicular joint dislocation. Then, the biomechanics of stainless steel and titanium alloy clavicle hook plates containing either six or eight screw holes were investigated. The results indicated that using a longer clavicle hook plate decreased the stress value in the clavicle, and mitigated the force that clavicle hook plates exert on the acromion. Using a clavicle hook plate material characterized by a smaller Young's modulus caused a slight increase in the stress on the clavicle. However, the external force the material imposed on the acromion was less than the force exerted on the clavicle. The findings of this study can serve as a reference to help orthopaedic surgeons select clavicle hook plates.

Effect of apical size and taper on volume of irrigant delivered at working length with apical negative pressure at different root curvatures.

PubMed

de Gregorio, Cesar; Arias, Ana; Navarrete, Natalia; Del Rio, Veronica; Oltra, Enrique; Cohenca, Nestor

2013-01-01

The purpose of this investigation was to determine the effect that apical preparation size and preparation taper have on the volume of irrigant delivered at the working length for different canal curvatures using apical negative pressure irrigation. One hundred fifty-five human teeth (55 maxillary canines and 100 mandibular molars) were used in this study. Root canals were prepared with rotary instruments to a size 35.04 and separated into 3 experimental groups according to their degree of curvature: group A (n = 50) included canal curvatures ranging from 0° to 10°, group B (n = 50) from 11° to 30°, and group C (n = 50) from 31° to 65°. Samples of each curvature group were further randomized to experimental subgroups according to the apical size and taper as follow: 35.06, 40.04, 40.06, 45.04, and 45.06. The apical third was irrigated using a microcannula and the volume of NaOCl suctioned at the working length under negative pressure was measured over a period of 30 seconds using a fluid recovery trap. Positive controls consisted of measuring the maximum volume of 5.25% NaOCl capable of being suctioned by the microcannula from an open glass vial over 30 seconds. Negative control was the volume of irrigant aspirated by the microcannula with a preparation size of 25.04 over 30 seconds. The volume of irrigant was significantly greater when the apical preparation size increased from 35.06 to 40.04. As the apical preparation taper increased further from 40.04 to 40.06, the volume of irrigant significantly improved in group B, but it was not significant in group A. Apical preparation sizes greater than 40.06 did not show an increase of the volume of irrigant aspirated. The degree of root canal curvature decreased the volume of irrigant at the working length for a given apical size and taper. An apical preparation of 40.06 significantly increased the volume and exchange of irrigant at the working length regardless of curvature. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Two dimensional vibrations of the guinea pig apex organ of Corti measured in vivo using phase sensitive Fourier domain optical coherence tomography

NASA Astrophysics Data System (ADS)

Ramamoorthy, Sripriya; Zhang, Yuan; Petrie, Tracy; Fridberger, Anders; Ren, Tianying; Wang, Ruikang; Jacques, Steven L.; Nuttall, Alfred L.

2015-02-01

In this study, we measure the in vivo apical-turn vibrations of the guinea pig organ of Corti in both axial and radial directions using phase-sensitive Fourier domain optical coherence tomography. The apical turn in guinea pig cochlea has best frequencies around 100 - 500 Hz which are relevant for human speech. Prior measurements of vibrations in the guinea pig apex involved opening the otic capsule, which has been questioned on the basis of the resulting changes to cochlear hydrodynamics. Here this limitation is overcome by measuring the vibrations through bone without opening the otic capsule. Furthermore, we have significantly reduced the surgery needed to access the guinea pig apex in the axial direction by introducing a miniature mirror inside the bulla. The method and preliminary data are discussed in this article.

How accurate replicates the Thermafil System the morphology of the apical endodontic space? An ex vivo study.

PubMed

Stratul, S I; Didilescu, Andreea; Grigorie, Mihaela; Ianes, Emilia; Rusu, D; Nica, Luminiţa

2011-01-01

To evaluate the morphology of the root canal in its apical third and the capacity of the Thermafil System to reproduce the entire morphology of the cleaned and shaped root canal. Thirty-two roots of periodontally compromised teeth were prepared using the ProTaper System to an apical size 30 and filled with the Thermafil obturation technique and sealer. The roots were surgically amputated and prepared for metallographic evaluation by incremental reductions of 0.5 mm each, starting with the apical foramen. Photomicrographs of each section were taken at a magnification of 500x and 100x. The images were analyzed and processed. The position of the apical foramen with respect to the anatomical apex was identified and marked. Additional morphological details as lateral canals and recesses were also recorded. The cross-sectioned area of the canal and gutta-percha, the total perimeter, the shaped perimeter and the filled perimeter were recorded for each sample and the results were expressed as percentages. Multiple images of successive sections were used to create a 3D reconstruction of the apical anatomy of the tooth. The ANOVA test was performed to assess mean differences between evaluations of perimeters/areas at different levels. The anatomical apical foramen was found at the tip of the root in 50% of the evaluated samples. In the remaining samples, the foramen was located between 0.5 and 2.5 mm from the centre of the apex. Lateral canals, which opened in accessory foramens, were recorded in 25% of the evaluated samples. Statistical significant differences (p<0.05) were found between different levels of preparation and obturation. The complex morphology of the apical third of the root canal is satisfactory microstructurally replicated by the Thermafil System. Moreover, polarized light microscopy and the 3D reconstruction offered a discriminative vision of morphological details as lateral canals, recesses, the gutta-percha and debris.

Subacromial morphometric assessment of the clavicle hook plate.

PubMed

ElMaraghy, Amr W; Devereaux, Moira W; Ravichandiran, Kajeandra; Agur, Anne M

2010-06-01

Clavicle hook plates are an effective plate fixation alternative for distal clavicle fractures and severe acromioclavicular joint dislocations. However, post-operative complications associated with the subacromial portion of the hook include acromial osteolysis and subacromial impingement. We examine and quantify the three-dimensional position of the subacromial portion of the hook plate relative to surrounding acromial and subacromial structures in a series of cadaveric shoulders to determine if hook positioning predisposes the shoulder to these noted post-operative complications. Fifteen cadaveric shoulders (seven males, eight females) were implanted with 15- or 18-mm hook plates. Dimensions of the acromion and hook plate were digitised and reconstructed into a three-dimensional model to measure acromion dimensions and distances of the subacromial hook relative to surrounding acromial and subacromial structures. Inter-specimen dimensions of the acromion were highly variable. Mean acromion width and thickness were greater in males than in females (p=0.01). The posterior orientation of the subacromial hook varied widely (mean posterior implantation angle=32.5+/-20 degrees, range 0-67 degrees). The hook pierced the subacromial bursa in 13/15 specimens, made contact with the belly of the supraspinatus muscle in 9/15 specimens, and had focal contact at the hook tip with the undersurface of the acromion in 9/15 specimens. The wide range of acromial dimensions leads to a high degree of variability in the positioning of the subacromial hook. The observed frequency of hook contact with surrounding subacromial structures in a static shoulder confirms that the position of the hook portion of the implant can predispose anatomic structures to the post-operative complications of subacromial impingement and bony erosion. Copyright 2009 Elsevier Ltd. All rights reserved.

Evolutionary anatomy of the muscular apparatus involved in the anchoring of Acanthocephala to the intestinal wall of their vertebrate hosts.

PubMed

Herlyn, Holger; Taraschewski, Horst

2017-04-01

Different conceptions exist regarding structure, function, and evolution of the muscles that move the acanthocephalan presoma, including the proboscis, i.e., the usually hooked hold-fast anchoring these endoparasites to the intestinal wall of their vertebrate definitive hosts. In order to clarify the unresolved issues, we carried out a light microscopic analysis of series of semi-thin sections and whole mounts representing the three traditional acanthocephalan classes: Archiacanthocephala (Macracanthorhynchus hirudinaceus), Eoacanthocephala (Paratenuisentis ambiguus, Tenuisentis niloticus), and Palaeacanthocephala (Acanthocephalus anguillae, Echinorhynchus truttae, Pomphorhynchus laevis, Corynosoma sp.). Combining our data with published light, transmission electron, and scanning electron microscopic data, we demonstrate that receptacle protrusor and proboscis receptacle in Archi- and Eoacanthocephala are homologous to the outer and inner wall of the proboscis receptacle in Palaeacanthocephala. Besides the proboscis receptacle and a "surrounding muscle," the last common ancestor of Acanthocephala presumably possessed a proboscis retractor, receptacle retractor, neck retractor (continuous with lemnisci compressors), and retinacula. These muscles most probably evolved in the acanthocephalan stem line. Moreover, the last common ancestor of Acanthocephala presumably possessed only a single layer of muscular cords under the presomal tegument while the metasomal body wall had circular and longitudinal strands. Two lateral receptacle flexors (also lateral receptacle protrusors), an apical muscle plate (surrounding one or two apical sensory organs), a midventral longitudinal muscle, and the differentiation of longitudinal body wall musculature at the base of the proboscis probably emerged within Archiacanthocephala. All muscles have a common organization principle: a peripheral layer of contractile filaments encloses the cytoplasm.

A descriptive study on the efficacy and complications of the Capio (Boston Scientific) suturing device for sacrospinous ligament fixation.

PubMed

Mowat, Alex; Wong, Vivien; Goh, Judith; Krause, Hannah; Pelecanos, Anita; Higgs, Peta

2018-02-01

Sacrospinous colpopexy is an effective vaginal apical support operation. Due to morbidity associated with traditional approaches which require wide dissection, slim-line suture delivery devices have been introduced in the hope of reducing morbidity without compromise to outcomes. The aim of our series was to report outcomes and complications (particularly buttock pain and blood loss) of the sacrospinous colpopexy using the Capio suturing device and evaluate it against published results using the Miya hook. This is a prospective, multi-centre descriptive study. The primary outcome is objective success at 12 months. Secondary outcomes include subjective success at 12 months, patient-reported outcomes at 12 months, operating time, estimated blood loss and post-operative buttock pain. Fifty-one consenting patients undergoing sacrospinous colpopexy were recruited at four Queensland hospitals. Objective success at 12 months was 95% (41/43) and subjective success at 12 months was 92% (44/48). Eighty-four percent of patients reported buttock pain at one week, reducing to 16% by six weeks, of which 7% required analgesia. At a mean of 17 months follow up, we found that the sacrospinous colpopexy using the Capio suturing device provided excellent apical support with a low requirement for blood transfusion and an average operating time of seven minutes. We found a high rate of buttock pain immediately post-operatively, but our rates became consistent with previous reports by six weeks post-operation. © 2017 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

HOMFLY for twist knots and exclusive Racah matrices in representation [333

NASA Astrophysics Data System (ADS)

Morozov, A.

2018-03-01

Next step is reported in the program of Racah matrices extraction from the differential expansion of HOMFLY polynomials for twist knots: from the double-column rectangular representations R = [ rr ] to a triple-column and triple-hook R = [ 333 ]. The main new phenomenon is the deviation of the particular coefficient f[ 332 ][ 21 ] from the corresponding skew dimension, what opens a way to further generalizations.

Biomechanical Analysis of Implanted Clavicle Hook Plates With Different Implant Depths and Materials in the Acromioclavicular Joint: A Finite Element Analysis Study.

PubMed

Lee, Cheng-Hung; Shih, Cheng-Min; Huang, Kui-Chou; Chen, Kun-Hui; Hung, Li-Kun; Su, Kuo-Chih

2016-11-01

Clinical implantation of clavicle hook plates is often used as a treatment for acromioclavicular joint dislocation. However, it is not uncommon to find patients that have developed acromion osteolysis or had peri-implant fracture after hook plate fixation. With the aim of preventing complications or fixation failure caused by implantation of inappropriate clavicle hook plates, the present study investigated the biomechanics of clavicle hook plates made of different materials and with different hook depths in treating acromioclavicular joint dislocation, using finite element analysis (FEA). This study established four parts using computer models: the clavicle, acromion, clavicle hook plate, and screws, and these established models were used for FEA. Moreover, implantations of clavicle hook plates made of different materials (stainless steel and titanium alloy) and with different depths (12, 15, and 18 mm) in patients with acromioclavicular joint dislocation were simulated in the biomechanical analysis. The results indicate that deeper implantation of the clavicle hook plate reduces stress on the clavicle, and also reduces the force applied to the acromion by the clavicle hook plate. Even though a clavicle hook plate made of titanium alloy (a material with a lower Young's modulus) reduces the force applied to the acromion by the clavicle hook plate, slightly higher stress on the clavicle may occur. The results obtained in this study provide a better reference for orthopedic surgeons in choosing different clavicle hook plates for surgery. Copyright © 2016 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

Temporary Iliac Fixation to Salvage an Acute L4 Chance Fracture: Following Pedicle Screw Fixation for Adolescent Idiopathic Scoliosis.

PubMed

Kato, So; Lewis, Stephen J

2017-03-01

A case report. The aim of this study was to describe a technique of temporary distal fixation to the ilium to salvage an acute L4 fracture following a T3-L4 kyphoscoliosis correction. Pedicle fracture is a possible complication in pedicle screw fixation for scoliosis, which may lead to postoperative instability, resulting in loss of fixation and pseudoarthrosis. This report highlights the salvage treatment of a chance fracture that occurred in the lower instrumented vertebra following deformity correction for adolescent idiopathic scoliosis (AIS) without sacrificing further distal motion segments. A retrospective chart and radiograph review of a 13-year-old female who underwent surgical treatment for correction of AIS was performed. Following a T3-L4 correction with apical posterior column releases, an L4 Chance fracture with loss of distal fixation occurred on post-op day 3. Following an unsuccessful salvage with an infralaminar hook, a second revision was performed replacing the hook and adding bilateral temporary fixation to the ilium connected to the distal ends of the main rods through side-to-side connectors. The temporary fixation was removed 6 months later with successful healing of the fracture maintenance of the scoliosis correction at 2-year follow-up. Temporary extension of the construct to the ilium was successfully utilized in this case to salvage an acute L4 Chance fracture that occurred following a T3 to L4 construct for kyphoscoliosis. With this technique, successful reduction and healing of the fracture occurred with maintenance of the deformity correction without the need to fuse further distal segments. 4.

76 FR 11961 - Safety Zone, Dredging Operations; Delaware River, Marcus Hook, PA

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-04

...-AA00 Safety Zone, Dredging Operations; Delaware River, Marcus Hook, PA AGENCY: Coast Guard, DHS. ACTION... Delaware River while the Dredge Pullen conducts dredging operations at the Sunoco Marcus Hook docks in the vicinity of the Marcus Hook Range near Marcus Hook, PA. This action is necessary to maintain the 42 ft...

[A retrospective study of 180 cases of apical microsurgery].

PubMed

Wang, Hanguo; Li, Dan; Tian, Yu; Yu, Qing

2014-07-01

To evaluate the outcome and the potential prognostic factors of apical microsurgery. The teeth with persistent periapical diseases were treated by microsurgery using micro instruments, ultrasonic retrotips and mineral trioxide aggregate (MTA) under dental operate microscope. The procedure includes incision and flap retraction, osteotomy, apicoectomy, retro- preparation and retro- filling of root canal. Patients were recalled at 1, 3, 6, and 12- month intervals. The outcome was evaluated by clinical and radiographic examinations, and the potential prognostic factors were analyzed. One hundred and eighty cases (240 teeth), including 132 upper anterior teeth, 22 lower anterior teeth, 31 upper premolars, 18 lower premolars, 19 upper molars and 18 lower molars, were treated by microsurgery between July 2010 and December 2012. A total of 152 cases (207 teeth) were recalled. The application of the apical microsurgery included failure of previous endodontic treatment, periapical lesion with post, periapical cyst, calcified canals, separated instruments, overfilling, open apex, root facture, failure of previous apical surgery, apical fenestration, and special root canal system. The success rate was 90.8% (188/207). Age, sex, tooth position, type of periapical radiolucency, fistula and clinical application type appeared to have a negative effect on the outcome. Endo-perio lesion was a significant factor. Eighteen cases (19 teeth) failed mainly because of periodontally involved lesion and vertical root fracture. Apical microsurgery, which combines the magnification and illumination provided by the microscope with the proper use of micro instruments, can treat the teeth with persistent periapical diseases precisely and less traumatically with high success rate. Case selection and standardized operations play a key role for success.

Comparative evaluation of apically extruded debris with V-Taper, ProTaper Next, and the Self-adjusting File systems.

PubMed

Vyavahare, Nishant K; Raghavendra, Srinidhi Surya; Desai, Niranjan N

2016-01-01

Complete cleaning of the root canal is the goal for ensuring success in endodontics. Removal of debris plays an important role in achieving this goal. In spite of advancements in instrument design, apical extrusion of debris remains a source of inflammation in the periradicular region. To comparatively evaluate the amount of apically extruded debris with V-Taper, ProTaper Next, and the self-adjusting File (SAF) system. Sixty-four extracted human mandibular teeth with straight root canals were taken. Access openings were done and working length determined. The samples were randomly divided into three groups: Group I - V-Taper files (n = 20), Group II - ProTaper Next (n = 20), Group III - SAF (n = 20). Biomechanical preparation was completed and the debris collected in vials to be quantitatively determined. The data obtained was statistically analyzed using ANOVA and post hoc Tukey's test. All the specimens showed apical debris extrusion. SAF showed significantly less debris extrusion compared to V-Taper and ProTaper Next (P < 0.001). Among Groups I and II, ProTaper Next showed lesser debris extrusion as compared to V-Taper, but it was not significant (P = 0.124). The SAF showed least amount of apical debris extrusion when compared to newer rotary endodontic instruments. This indicates that the incidence of inter-treatment flare-ups due to debris extrusion would be less with the SAF.

The thoracic muscular system and its innervation in third instar Calliphora vicina Larvae. I. Muscles of the pro- and mesothorax and the pharyngeal complex.

PubMed

Hanslik, Ulrike; Schoofs, Andreas; Niederegger, Senta; Heinzel, Hans-Georg; Spiess, Roland

2010-08-01

An anatomical description is given by the muscles in the pro- and mesothorax, and those associated with the feeding apparatus (cephalopharyngeal skeleton, CPS) that participate in feeding behavior in third instar Calliphora larvae. The body wall muscles in the pro- and mesothoracic segments are organized in three layers: internal, intermedial, and external. The muscles were labeled with roman numerals according to the nomenclature in use for the abdominal segments. Muscles associated with the CPS are labeled according to their function. The prothorax bears five pairs of lateral symmetrically longitudinal segmental body wall muscles and lacks the transversal muscle group present in the mesothorax and abdominal segments. Additionally, four pairs of intersegmental muscles project from the prothorax to the second, fourth, and fifth segment. The mesothorax bears 15 pairs of segmental longitudinal and 18 pairs of transversal muscles. The accessory pharyngeal muscles span the CPS and the cuticle. Three pairs of protractors and retractors and two pairs of mouth hook accessors (MH(AC)) exist, which move the CPS relative to the body. The pharyngeal muscles are exclusively attached to the structures of the CPS. The mouth hook elevators and depressors, which mediate the hooks rotation are attached to the ventral arm of the CPS and project to a dorsal (elevators) or ventral (depressors) protuberance of the mouth hooks. The cibarial dilator muscles (CDM) span the dorsal arms of the CPS and the dorsal surface of the esophagus and mediate food ingestion. The labial retractors (LRs) lack antagonists and project from the ventral surface of the CPS to the unpaired labium. Contractions of these muscles open the mouth cavity. J. Morphol. 271:960-968, 2010. (c) 2010 Wiley-Liss, Inc.

[Clinical auxiliary diagnosis value of high frequency ultrasonographic measurements of the thickness of transverse carpal ligaments in carpal tunnel syndrome patients].

PubMed

Xu, L; Chen, F M; Wang, L; Zhang, P X; Jiang, X R

2016-04-18

To evaluate the meaning and value of high-frequency ultrasound in the diagnosis of carpal tunnel syndrome (CTS). In this study, 48 patients (unilateral hand) with CTS were analyzed. The thickness of transverse carpal ligaments at the pisiform bone was measured using high-frequency ultrasound. Open carpal tunnel release procedure was performed in the 48 CTS patients, and the thickness of transverse carpal ligaments at the hamate hook bone measured using vernier caliper under direct vision. The accuracy of thickness of transverse carpal ligaments was evaluated using high-frequency ultrasound. high-frequency ultrasound measurement of thickness of transverse carpal ligaments at the hamate hook bone and pisiform bone, and determination of the diagnostic threshold measurement index using receiver operating characteristic (ROC) curve, sensitivity and specificity were performed and the correlation between the thickness of transverse carpal ligaments and nerve conduction study (NCS) analyzed. The thickness of transverse carpal ligaments in the CTS patients were (0.42±0.08) cm (high-frequency ultrasound) and (0.41±0.06) cm (operation) at hamate hook bone, and there was no significant difference between the two ways (t=0.672, P>0.05). The optimal cut-off value of the transverse carpal ligaments at hamate hook bone was 0.385 cm, the sensitivity 0.775, and the specificity 0.788. The optimal cut-off value of the transverse carpal ligaments at the pisiform bone was 0.315 cm, the sensitivity 0.950, and the specificity 1.000. The transverse carpal ligaments thickness and wrist-index finger sensory nerve conduction velocity (SCV), wrist-middle finger SCV showed a negative correlation. High frequency ultrasound measurements of thickness of transverse carpal ligaments is a valuable method for the diagnosis of CTS.

Assessing the Personal Negative Impacts of Hooking Up Experienced by College Students: Gender Differences and Mental Health.

PubMed

Napper, Lucy E; Montes, Kevin S; Kenney, Shannon R; LaBrie, Joseph W

2016-09-01

Hooking up is a normative behavior among college students that is associated with a range of positive and negative consequences. While previous research has primarily focused on women's negative experiences of hooking up, the current study explored the relationships among hooking up behaviors, psychological distress, and a broad range of negative effects of hooking up in both male and female college students. Using a multisite sample of college students, we developed the 14-item Negative Impact of Hookups Inventory (NIHI) to assess negative health outcomes, emotional responses, and social consequences associated with hooking up. Unprotected sex and having more hookup partners were associated with greater negative experiences of hooking up. Contrary to expectations, there were no gender differences in the total number of negative hookup effects, although men reported more frequent hookups. In addition, negative impacts of hooking up were positively associated with psychological distress regardless of gender. The NIHI may offer a useful tool to assess the negative impacts of hooking up. Understanding students' hookup experiences is an important step toward developing targeted health interventions related to hooking up behavior in young adult populations.

Estimating freshwater turtle mortality rates and population declines following hook ingestion.

PubMed

Steen, David A; Robinson, Orin J

2017-12-01

Freshwater turtle populations are susceptible to declines following small increases in the mortality of adults, making it essential to identify and understand potential threats. Freshwater turtles ingest fish hooks associated with recreational angling, and this is likely a problem because hook ingestion is a source of additive mortality for sea turtles. We used a Bayesian-modeling framework, observed rates of hook ingestion by freshwater turtles, and mortality of sea turtles from hook ingestion to examine the probability that a freshwater turtle in a given population ingests a hook and subsequently dies from it. We used the results of these analyses and previously published life-history data to simulate the effects of hook ingestion on population growth for 3 species of freshwater turtle. In our simulation, the probability that an individual turtle ingests a hook and dies as a result was 1.2-11%. Our simulation results suggest that this rate of mortality from hook ingestion is sufficient to cause population declines. We believe we have identified fish-hook ingestion as a serious yet generally overlooked threat to the viability of freshwater turtle populations. © 2017 Society for Conservation Biology.

Treatment of Mature Permanent Teeth with Necrotic Pulps and Apical Periodontitis Using Regenerative Endodontic Procedures: A Case Series.

PubMed

Saoud, Tarek Mohamed; Martin, Gabriela; Chen, Yea-Huey M; Chen, Kuang-Liang; Chen, Chao-An; Songtrakul, Kamolthip; Malek, Matthew; Sigurdsson, Asgeir; Lin, Louis M

2016-01-01

Regenerative endodontic procedures (REPs) are usually used to treat human immature permanent teeth with necrotic pulps and/or apical periodontitis. Successful REPs result in the elimination of clinical signs/symptoms, the resolution of apical periodontitis, and, in some cases, thickening of the canal walls and/or continued root development with or without apical closure. REPs can restore the vitality of tissue in the canals of immature permanent teeth previously destroyed by infection or trauma. Vital tissue is inherited with immune defense mechanisms to protect itself from foreign invaders. Recently, REPs have also been used to successfully treat human mature permanent teeth with necrotic pulps and apical periodontitis. The purpose of this case series was to present the potential of using REPs for mature permanent teeth with necrotic pulps and apical periodontitis. This case series consisted of 6 patients, 4 females and 2 males. The patients' ages ranged from 8-21 years old. Seven permanent teeth, 4 anterior and 3 molar teeth, with necrotic pulps and apical periodontitis were treated using REP. Radiographically, the root development of all teeth was almost completed except the apices of 2 molars, which showed slightly open. Complete chemomechanical debridement of the canals of the teeth was performed, and the canals were dressed with Metapaste (Meta Biomed Co, Ltd, Chungbuk, Korea) during treatment visits. Periapical bleeding into the canals was induced at the last treatment visit by placing a hand #20 or #25 K-file with the tip slightly bent through the apical foramina into the periapical tissues. A 3-mm thickness of mineral trioxide aggregate was placed into the coronal canals over semicoagulated blood. The access cavities were restored with either composite resin or amalgam. Follow-ups of the 7 teeth ranged from 8 to 26 months. The periapical lesions of 2 teeth were considered healed, and 5 teeth revealed healing. Clinical signs/symptoms were absent in all teeth at follow-up visits at different time points. None of the treated teeth responded to cold and electric pulp tests. This case series shows the potential of using REPs for mature teeth with necrotic pulp and apical periodontitis. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Semi-rigid single hook localization the best method for localizing ground glass opacities during video-assisted thoracoscopic surgery: re-aerated swine lung experimental and primary clinical results

PubMed Central

Zhao, Guang; Sun, Long; Geng, Guojun; Liu, Hongming; Li, Ning; Liu, Suhuan; Hao, Bing

2017-01-01

Background The aim of this study was to compare the effects of currently available preoperative localization methods, including semi-rigid single hook-wire, double-thorn hook-wire, and microcoil, in localizing the pulmonary nodules, thus to select the best technology to assist video-assisted thoracoscopic surgery (VATS) for small ground glass opacities (GGO). Methods Preoperative CT-guided localizing techniques including semi-rigid single hook-wire, double-thorn hook-wire and microcoil were used in re-aerated fresh swine lung for location experiments. The advantages and drawbacks of the three positioning technologies were compared, and then the most optimal technique was used in patients with GGO. Technical success and post-operative complications were used as primary endpoints. Results All three localizing techniques were successfully performed in the re-aerated fresh swine lung. The median tractive force of semi-rigid single hook wire, double-thorn hook wire and microcoil were 6.5, 4.85 and 0.2 N, which measured by a spring dynamometer. The wound sizes in the superficial pleura, caused by unplugging the needles, were 2 mm in double-thorn hook wire, 1 mm in semi-rigid single hook and 1 mm in microcoil, respectively. In patients with GGOs, the semi-rigid hook wires localizations were successfully performed, without any complication that need to be intervened. Dislodgement was reported in one patient before VATS. No major complications related to the preoperative hook wire localization and VATS were observed. Conclusions We found from our localization experiments in the swine lung that, among the commonly used three localization methods, semi-rigid hook wire showed the best operability and practicability than double-thorn hook wire and microcoil. Preoperative localization of small pulmonary nodules with single semi-rigid hook wire system shows a high success rate, acceptable utility and especially low dislodgement in VATS. PMID:29312722

Ultrastructure and chemical composition of the proboscis hooks of Acanthocephalus lucii (Müller, 1776) (Acanthocephala: Palaeacanthocephala) using X-ray elemental analysis.

PubMed

Brázová, Tímea; Poddubnaya, Larisa G; Miss, Noemí Ramírez; Hanzelová, Vladimíra

2014-12-01

The ultrastructure and chemical composition of the proboscis hooks and surrounding tegument of Acanthocephalus lucii (Müller, 1776), a parasite of European perch, Perca fluviatilis Linnaeus, were examined using scanning (SEM) and transmission (TEM) electron microscopy and X-ray microanalysis (EDXA). The blade of middle hooks consists of three layers: an outer homogeneous layer, an inner heterogeneous layer and a central core. TEM observation revealed the presence of hollow tubes, which spaced the central core; fibrous inner hook layer surrounded by an electron-dense margin and the basal tegumental layer filled with electron-dense bodies and outer layer. We found for the first time that the so-called 'epidermal covering' surrounding of the exposed hook blade (outer hook layer) is a modified striped portion of the tegumental layer and there are no special contact sites between these two morphologically different structures, i.e. striped layer of the syncytial tegument and following proper outer hook layer, which is a homogeneous, moderately electron-dense layer of -0.3 μm in thickness. The hook root is embedded into subtegumental fibrous layer. X-ray microanalysis of both the surface and internal parts of A. lucii hooks demonstrated the presence of calcium, magnesium, phosphorus and sulphur. The highest concentration of sulphur was recorded at the tip of hooks, whereas the middle part of the hooks was most rich in calcium, phosphorus and magnesium. The proximal part of the hooks contained lower concentrations of sulphur, calcium and phosphorus. In the proboscis tegument, only two elements, calcium and silicon, were found. The differences observed in the chemical composition of the hook 'epidermal covering' and the proboscis tegument support our ultrastructural findings that the hook tegumental covering is a modified structure compared with that of the general proboscis tegument.

Robotic End Effectors for Hard-Rock Climbing

NASA Technical Reports Server (NTRS)

Kennedy, Brett; Leger, Patrick

2004-01-01

Special-purpose robot hands (end effectors) now under development are intended to enable robots to traverse cliffs much as human climbers do. Potential applications for robots having this capability include scientific exploration (both on Earth and other rocky bodies in space), military reconnaissance, and outdoor search and rescue operations. Until now, enabling robots to traverse cliffs has been considered too difficult a task because of the perceived need of prohibitively sophisticated planning algorithms as well as end effectors as dexterous as human hands. The present end effectors are being designed to enable robots to attach themselves to typical rock-face features with less planning and simpler end effectors. This advance is based on the emulation of the equipment used by human climbers rather than the emulation of the human hand. Climbing-aid equipment, specifically cams, aid hooks, and cam hooks, are used by sport climbers when a quick ascent of a cliff is desired (see Figure 1). Currently two different end-effector designs have been created. The first, denoted the simple hook emulator, consists of three "fingers" arranged around a central "palm." Each finger emulates the function of a particular type of climbing hook (aid hook, wide cam hook, and a narrow cam hook). These fingers are connected to the palm via a mechanical linkage actuated with a leadscrew/nut. This mechanism allows the fingers to be extended or retracted. The second design, denoted the advanced hook emulator (see Figure 2), shares these features, but it incorporates an aid hook and a cam hook into each finger. The spring-loading of the aid hook allows the passive selection of the type of hook used. The end effectors can be used in several different modes. In the aid-hook mode, the aid hook on one of the fingers locks onto a horizontal ledge while the other two fingers act to stabilize the end effector against the cliff face. In the cam-hook mode, the broad, flat tip of the cam hook is inserted into a non-horizontal crack in the cliff face. A subsequent transfer of weight onto the end effector causes the tip to rotate within the crack, creating a passive, self-locking action of the hook relative to the crack. In the advanced hook emulator, the aid hook is pushed into its retracted position by contact with the cliff face as the cam hook tip is inserted into the crack. When a cliff face contains relatively large pockets or cracks, another type of passive self-locking can be used. Emulating the function of the piece of climbing equipment called a "cam" (note: not the same as a "cam hook"; see Figure 1), the fingers can be fully retracted and the entire end effector inserted into the feature. The fingers are then extended as far as the feature allows. Any weight then transferred to the end effector will tend to extend the fingers further due to frictional force, passively increasing the grip on the feature. In addition to the climbing modes, these end effectors can be used to walk on (either on the palm or the fingertips) and to grasp objects by fully extending the fingers.

29 CFR 1915.113 - Shackles and hooks.

Code of Federal Regulations, 2010 CFR

2010-07-01

... bends or springs the hook. (3) Hooks shall be inspected periodically to see that they have not been bent by overloading. Bent or sprung hooks shall not be used. [47 FR 16986, Apr. 20, 1982, as amended at 51...

29 CFR 1915.113 - Shackles and hooks.

Code of Federal Regulations, 2011 CFR

2011-07-01

... bends or springs the hook. (3) Hooks shall be inspected periodically to see that they have not been bent by overloading. Bent or sprung hooks shall not be used. [47 FR 16986, Apr. 20, 1982, as amended at 51...

75 FR 19561 - Fisheries of the Economic Exclusive Zone Off Alaska; Pacific Cod in the Bering Sea and Aleutian...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-15

... is opening directed fishing for Pacific cod by catcher vessels less than 60 feet (18.3 meters) length... meters) length overall using hook-and-line or pot gear in the BSAI under Sec. 679.20(d)(1)(iii) on March... 400 metric tons of Pacific cod remain in the 2010 Pacific cod apportionment for catcher vessels less...

75 FR 52478 - Fisheries of the Economic Exclusive Zone Off Alaska; Pacific Cod in the Bering Sea and Aleutian...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-26

... is opening directed fishing for Pacific cod by catcher vessels less than 60 feet (18.3 meters) length... catcher vessels less than 60 feet (18.3 meters) LOA using hook-and-line or pot gear specified for the BSAI... 679. NMFS closed directed fishing for Pacific cod by catcher vessels less than 60 feet (18.3 meters...

Drawings of fossils by Robert Hooke and Richard Waller

PubMed Central

Kusukawa, Sachiko

2013-01-01

The drawings of fossils by Robert Hooke and Richard Waller that were the basis of the engravings in Hooke's Posthumous works (1705) are published here for the first time. The drawings show that both Hooke and Waller were proficient draftsmen with a keen eye for the details of petrified objects. These drawings provided Hooke with a polemic edge in making the case for the organic origins of ‘figured stones’.

Instability of hooks during bacterial flagellar swimming

NASA Astrophysics Data System (ADS)

Jabbarzadeh, Mehdi; Fu, Henry C.; Henry Fu Team

2016-11-01

In bacteria, a flexible hook transmits torque from the rotary motor at the cell body to the flagellum. Previously, the hook has been modeled as a Kirchhoff rod between the cell body and rotating flagellum. To study effects of the hook's flexibility on the bacteria's swimming speed and trajectory for wide range hook stiffnesses and flagellum configurations, we develop an efficient simplified spring model for the hook by linearizing the Kirchhoff rod. We treat the hydrodynamics of the cell body and helical flagellum using resistance matrices calculated by the method of regularized Stokeslets. We investigate flagellar and swimming dynamics for a range of hook flexibilities and flagellar orientations relative to the cell body and compare the results to models without hook flexibility. We investigate in detail parameters corresponding to E. coli and Vibrio alginolyticus. Generally, the flagellum changes orientation relative to the cell body, undergoing an orbit with the period of the motor rotation. We find that as the hook stiffness decreases, steady-state orbits of the flagellum first become unstable before the hook buckles, which may suggest a new mechanism of flick initiation in run-reverse-flick motility. We also find that for some parameter ranges, there are multiple stable steady state orbits, which may have implications for the tumbling and turning of bacteria.

[Difficilina cerebratuli gen. et sp. n. (Eugregarinida: Lecudinidae)--a new gregarine species from the nemertean Cerebratulus barentsi (Nemertini: Cerebratulidae)].

PubMed

Simdianov, T G

2009-01-01

A new species of aseptate gregarine, Difficilina cerebratuli gen. et sp. n. (order Eugregarinida Leger, 1900; suborder Aseptata Chakravarty, 1960; family Lecudinidae Kamm, 1922) from the gut of the White Sea nemertean Cerebratulus barentsi Bürger, 1895, has been described. The electron and light microscopic data on trophozoites are presented. Their general morphology resembles the representatives of the genus Lecudina, but the features of the epicyte ultrastructure are different from Lecudina and similar to those of the Lankesteria spp. Taxonomy of the described species is discussed. Certain ultrastructural characters are included in its generic and specific diagnoses. Genus Difficilina gen. n. Type species: Difficilina cerebratuli sp. n. Characters of the family. Free trophozoites elongated, anterior end rounded, without hooks or exfoliations, not separated from the rest of the body, with well-developed terminal smooth area. The epicytic folds undulating vertically, in cross sections--monomorphic, finger-shaped, with strongly developed cell-coat, with additional electron-dense axial structure ("middle axis") at the tops; number of rippled dense structurtes and apical filaments 3, the furthers are thick and slightly flattened in diameter. Other stages unknown. In testinal parasites of nemerteans. The new genus differs from Lecudina by presence of smooth area at the apical pole of the body and the epicyte structure: vertically undulating monomorphic finger-shaped (in cross section) epicytic folds, oligomerization of the rippled dense structures and apical filaments, and development of the "middle axis". It also differs from Lankesteria by the shape of the body, vertical undulation of the folds, and non-tunicate host. Difficilina cerebratuli sp. n. Characters of the genus. Free trophozoites slightly bent, up to 250 x 70 microm. Anterior end with less granular cytoplasm; with feebly marked apical papilla encircled by the smooth area. Posterior end pointed. The average height of the epicytic folds is 280 nm, thickness--160 nm, average distance between folds is 130 nm. Endoplasm contains a number of accumulations of the fibrillar matter. Nucleus spherical 14-26 microm in diameter, localized in the middle or in the fore third of the body, carries 1-2 karyosomes of various size. Other stages unknown. TYPE SERIES: Microscopical slide with 7 trophozoites (Bouin, Delafield's haematoxylin) is kept in the Zoological museum of the Moscow State University (collection number: Z-2). In addition, two syntypes are observed with TEM and two other syntypes--with SEM. TYPE HOST: Cerebratulus barentsi Bürger, 1895 (Nemertini: Cerebratulidae). Intestine (?). TYPE LOCALITY: White Sea Biological Station of the Moscow State University, Yeremeyevsky Rapid, Velikaya Salma Strait, Kandalaksha Bay, White Sea.

The effects of flagellar hook compliance on motility of monotrichous bacteria: A modeling study

NASA Astrophysics Data System (ADS)

Shum, H.; Gaffney, E. A.

2012-06-01

A crucial structure in the motility of flagellated bacteria is the hook, which connects the flagellum filament to the motor in the cell body. Early mathematical models of swimming bacteria assume that the helically shaped flagellum rotates rigidly about its axis, which coincides with the axis of the cell body. Motivated by evidence that the hook is much more flexible than the rest of the flagellum, we develop a new model that allows a naturally straight hook to bend. Hook dynamics are based on the Kirchhoff rod model, which is combined with a boundary element method for solving viscous interactions between the bacterium and the surrounding fluid. For swimming in unbounded fluid, we find good support for using a rigid model since the hook reaches an equilibrium configuration within several revolutions of the motor. However, for effective swimming, there are constraints on the hook stiffness relative to the scale set by the product of the motor torque with the hook length. When the hook is too flexible, its shape cannot be maintained and large deformations and stresses build up. When the hook is too rigid, the flagellum does not align with the cell body axis and the cell "wobbles" with little net forward motion. We also examine the attraction of swimmers to no-slip surfaces and find that the tendency to swim steadily close to a surface can be very sensitive to the combination of the hook rigidity and the precise shape of the cell and flagellum.

Synthetic Minor NSR Permit: Van Hook Crude Terminal, LLC - Van Hook Crude Terminal/Rail Loading Facility

EPA Pesticide Factsheets

This page contains the current effective synthetic minor NSR permit for the Van Hook Crude Terminal, LLC, Van Hook Crude Terminal/Rail Loading Facility, located on the Fort Berthold Indian Reservation in Mountrail County, ND.

Three-dimensional scapular dyskinesis in hook-plated acromioclavicular dislocation including hook motion.

PubMed

Kim, Eugene; Lee, Seunghee; Jeong, Hwa-Jae; Park, Jai Hyung; Park, Se-Jin; Lee, Jaewook; Kim, Woosub; Park, Hee Jin; Lee, So Yeon; Murase, Tsuyoshi; Sugamoto, Kazuomi; Ikemoto, Sumika

2018-06-01

The purpose of this study is to analyze the 3-dimensional scapular dyskinesis and the kinematics of a hook plate relative to the acromion after hook-plated acromioclavicular dislocation in vivo. Reported complications of acromioclavicular reduction using a hook plate include subacromial erosion and impingement. However, there are few reports of the 3-dimensional kinematics of the hook and scapula after the aforementioned surgical procedure. We studied 15 cases of acromioclavicular dislocation treated with a hook plate and 15 contralateral normal shoulders using computed tomography in the neutral and full forward flexion positions. Three-dimensional motion of the scapula relative to the thorax during arm elevation was analyzed using a computer simulation program. We also measured the distance from the tip of the hook plate to the greater tuberosity, as well as the angular motion of the plate tip in the subacromial space. Decreased posterior tilting (22° ± 10° vs 31° ± 8°) in the sagittal plane and increased external rotation (19° ± 9° vs 7° ± 5°) in the axial plane were evident in the affected shoulders. The mean values of translation of the hook plate and angular motion against the acromion were 4.0 ± 1.6 mm and 15° ± 8°, respectively. The minimum value of the distance from the hook plate to the humeral head tuberosity was 6.9 mm during arm elevation. Acromioclavicular reduction using a hook plate may cause scapular dyskinesis. Translational and angular motion of the hook plate against the acromion could lead to subacromial erosion. However, the hook does not seem to impinge directly on the humeral head. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Absorption of metals in mulloway (Argyrosomus japonicus) after ingesting nickel-plated carbon-steel hooks.

PubMed

McGrath, Shane P; Reichelt-Brushett, Amanda J; Butcher, Paul A; Cairns, Stuart C

2014-08-01

Previous research has alluded to the potential of metals being absorbed by fish after ingesting fishing hooks, which may have adverse effects on fish health and the organisms that consume them. Subsequently, this study aimed to quantify the potential of mulloway (Argyrosomus japonicus) to absorb metals during the decay of ingested nickel-plated carbon-steel hooks. Twenty-five treatment fish were allowed to ingest nickel-plated carbon-steel hooks during angling and then monitored with 25 controls (untreated fish) for up to 42 days for hook ejection and mortality. Blood, liver and muscle samples were collected from treatment, control and 14 wild-caught individuals to determine the concentrations of chromium, cobalt, copper, iron, manganese and nickel. The results showed that increased oxidation influenced hook ejection, and that hook-ingested fish had significantly elevated concentrations of nickel in their liver and blood, but not muscle. This research has shown that there is an avenue for metal absorption from ingested hooks. Copyright © 2014 Elsevier Ltd. All rights reserved.

Casual hook up sex during the first year of college: Prospective associations with attitudes about sex and love relationships.

PubMed

Katz, Jennifer; Schneider, Monica E

2013-11-01

This study examined bidirectional relationships among emerging adults' involvement in casual hook up sex and attitudes about sex and love relationships. At the start and end of their first year in college, undergraduates (N = 163) responded to measures of sexual behavior, sexual attitudes, and attitudes about love relationships. In cross-sectional analyses, attitudes about sex and love both were associated with involvement in casual hook up sex. In prospective analyses, initial attitudes about sexual instrumentality uniquely predicted involvement in later hook up sex, even after controlling for past hook up sex. Furthermore, involvement in hook up sex during the first year of college predicted greater sexual permissiveness and comfort with casual genital contact, even after controlling for initial sexual attitudes and hook up behaviors. None of the associations between attitudes and behavior were qualified by gender. Experiences of causal hook up sex appear to have implications primarily for emerging adults' attitudes about sexual interactions rather than their attitudes about love relationships.

The hooked element in the pes of turtles (Testudines): a global approach to exploring primary and secondary homology

PubMed Central

Joyce, Walter G; Werneburg, Ingmar; Lyson, Tyler R

2013-01-01

The hooked element in the pes of turtles was historically identified by most palaeontologists and embryologists as a modified fifth metatarsal, and often used as evidence to unite turtles with other reptiles with a hooked element. Some recent embryological studies, however, revealed that this element might represent an enlarged fifth distal tarsal. We herein provide extensive new myological and developmental observations on the hooked element of turtles, and re-evaluate its primary and secondary homology using all available lines of evidence. Digital count and timing of development are uninformative. However, extensive myological, embryological and topological data are consistent with the hypothesis that the hooked element of turtles represents a fusion of the fifth distal tarsal with the fifth metatarsal, but that the fifth distal tarsal dominates the hooked element in pleurodiran turtles, whereas the fifth metatarsal dominates the hooked element of cryptodiran turtles. The term ‘ansulate bone’ is proposed to refer to hooked elements that result from the fusion of these two bones. The available phylogenetic and fossil data are currently insufficient to clarify the secondary homology of hooked elements within Reptilia. PMID:24102560

75 FR 4265 - Airworthiness Directives; Lifesavings Systems Corp., D-Lok Hook Assembly

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-27

... Airworthiness Directives; Lifesavings Systems Corp., D-Lok Hook Assembly AGENCY: Federal Aviation Administration... adopting a new airworthiness directive (AD) for the Lifesavings Systems Corp., D-Lok Hook assembly... reported surface irregularities and discontinuities on certain D-Lok Hooks because of an unapproved change...

Development and impact of hooks of large droplet concentration on remote southeast Pacific stratocumulus

NASA Astrophysics Data System (ADS)

George, R. C.; Wood, R.; Bretherton, C. S.; Painter, G.

2013-01-01

Over the southeastern Pacific (SEP), droplet concentration (Nd) in the typically unpolluted marine stratocumulus west of 80° W (> 1000 km offshore) is periodically strongly enhanced in zonally-elongated "hook"-shaped arcs that increase albedo. Here, we examine three hook events using the chemistry version of the Weather Research and Forecasting model (WRF-Chem) with 14 km horizontal resolution, satellite data and aircraft data from the VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx). A particularly strong hook yields insights to the development, decay, and radiative impact of these features. Hook development occurs with Nd increasing to polluted levels over the remote ocean primarily due to entrainment of cloud condensation nuclei (CCN) from the free troposphere (FT). The feature advects northwestward until the FT CCN source is depleted, after which Nd decreases over a few days due to precipitation and dilution. The model suggests that the FT CCN source supplying the hook consists of high concentrations of small accumulation mode aerosols that contribute a relatively small amount of aerosol mass to the MBL. The aerosol particles originate mainly from a pulse of offshore flow that transports Santiago region (33-35° S) emissions to the marine FT. To provide a sustained hook CCN source, the FT transport of pollution plumes to the remote ocean requires strong, deep offshore flow. Such flow is favored by a trough approaching the South American coast and a southeastward shift of the climatological subtropical high pressure system. The model simulations show precipitation suppression in the hook and a corresponding increase in liquid water path (LWP) compared with a simulation without anthropogenic sources. LWP also increases in time as the hook evolves due to increasing stability and decreasing subsidence. WRF-Chem suggests that DMS significantly influences the aerosol number and size distributions in a hook, but that hooks do not form without FT CCN. The Twomey effect contributes ~ 50-70% of the albedo increase due the presence of the hook, while secondary aerosol indirect effects and meteorological influences also contribute significantly. The source of hook aerosols is difficult to determine with the available observations alone. The model explains the observations and puts them in context of the factors influencing hook formation. Two other weaker hooks during VOCALS-REx are not as well simulated but are also associated with FT offshore flow near Santiago. Hooks demonstrate the importance of free-tropospheric transport of aerosols in modulating the droplet concentration in the southeastern Pacific stratocumulus deck, and present a formidable challenge to simulate accurately in large scale models.

Effect of different mixing and placement methods on the quality of MTA apical plug in simulated apexification model.

PubMed

Ghasemi, Negin; Janani, Maryam; Razi, Tahmineh; Atharmoghaddam, Faezeh

2017-03-01

It is necessary apical plug material to exhibit proper adaptation with the root canal walls. Presence of voids at the interface between the root canal wall and this material result in micro leakage, which might have a relationship with post treatment disease. The aim of the present study was to evaluate the effect of different mixing (manual and ultrasonic) and placement (manual and manual in association with indirect ultrasonic) method of Mineral Trioxide Aggregate (MTA) on the void count and dimension in the apical plug in natural teeth with simulated open apices. Eighty human maxillary central incisors were selected. After simulation of the open apex model, the teeth were assigned to 4 groups based on the mixing and placement techniques of MTA: group 1, manual mixing and manual placement; group 2, manual mixing and manual placement in association with indirect ultrasonic; group 3, ultrasonic mixing and and manual placement; and group 4, ultrasonic mixing and manual placement in association with indirect ultrasonic. The prepared samples were placed within gypsum sockets in which the periodontal ligament was reconstructed with polyether impression material. In group 1, after mixing, the material was condensed with a hand plugger. In group 2, after mixing, the ultrasonic tip was contacted with the hand plugger for 2 seconds. In groups 3 and 4, mixing was carried out with the ultrasonic tip for 5 seconds and in groups 3 and 4, similar to groups 1 and 2, respectively, the materials were placed as apical plugs, measuring 3 mm in length. A wet cotton pellet was placed at canal orifices and dressed with Cavit. After one week, the cone beam computed tomography (CBCT) technique was used to count the number of voids between the material and root canal walls. The void dimensions were determined using the following scoring system: score 1, absence of voids; score 2, the void size less than half of the dimensions of the evaluated cross-section; score 3, the void size larger than half of the dimensions of the evaluated cross-section. Chi-squared and Fisher's exact tests were used for statistical analyses. Statistical significance was set at P <0.05. The maximum (13) and minimum (3) number of voids were detected in groups 2 and 3, respectively. There were no significant differences between groups 1 and 3 in the number of voids ( p >0.05). Evaluation of void dimensions showed no score 3 in any of the study groups and the dimensions of all the voids conformed to score 2. Under the limitations of the present study, use of ultrasonic mixing and manual placement techniques resulted in a decrease in the number of voids in the apical plug. Key words: Apical plug, MTA, ultrasonic, void.

Aluminum Manganese Molten Salt Plating

DTIC Science & Technology

2006-06-01

fixture from overhead crane hook and locate fixture over the closed acid tank. 2. Ventilation a. Set valve positions as follows (same as Section I.4.a...overhead crane hook and position the fixture over the closed acid tank. (Will need to remove the top stainless steel rod, clasp the remaining rod with the... crane hook , replace the rod that was removed by threading it through the crane hook , and finally lift the fixture off its storage hook . The cotter

Ingestion and ejection of hooks: effects on long-term health and mortality of angler-caught yellowfin bream Acanthopagrus australis.

PubMed

Broadhurst, Matt K; Butcher, Paul A; Brand, Craig P; Porter, Mark

2007-02-08

Ninety juvenile yellowfin bream Acanthopagrus australis were angled from holding tanks, allowed to ingest nickel-plated, carbon-steel J-hooks and released (with their lines cut) into individual experimental tanks during 2 experiments in order to assess their (1) long-term (up to 105 d) health, mortality and rate of hook ejection and (2) short- and medium-term (< 42 d) temporal changes in health during hook ingestion. Equal numbers of control fish were scooped from holding tanks and similarly monitored in experimental tanks. Of 20 hook-ingested fish released during Expt 1, 3 died within 8 d, providing a non-significant mortality of 15%. Between Day 6 and Day 56 post-release, 13 of the surviving individuals ejected their hooks, which were typically oxidized to about 94% of their original weight and often broken into 2 pieces. At Day 105, there were no significant differences between the 20 control and 17 hook-ingested/-ejected fish in terms of their ability to digest and assimilate food (measured as changes in apparent digestibility coefficients), stress (measured as concentrations of plasma cortisol and glucose) or of morphological parameters that included weight (Wt) and maximum height (MH), maximum width (MW) and maximum girth (MG). During Expt 2, 3 individuals that still contained ingested hooks and 3 controls were sampled on each of 9 occasions between Day 3 and Day 42 post-release. All fish were sampled for blood cortisol and glucose and were then euthanized before being weighed and measured for total length (TL), MH, MW and MG. Hook-ingested individuals were also X-rayed to determine the position and orientation of hooks. There were no significant differences in plasma glucose between hook-ingested and control fish. Irrespective of the treatment of fish, concentrations of cortisol were elevated on some sampling occasions, indicating variable, acute stress. The MH and MG of fish were not significantly different between groups. Significant differences were detected for MG and Wt, with hook-ingested fish having weights similar to those of the control fish but a relatively greater MW (owing to stomach distension from ingested hooks) until 2 wk post-release, after which both morphological parameters generally declined. There was no significant temporal progression of hooks in the stomach of treatment fish; however, some hooks reorientated to positions that may have precluded passage along the digestive tract. We conclude that, for the J-hooks examined, cutting the line is an appropriate strategy that results in the greater majority of released hook-ingested yellowfin bream surviving with minimal negative long-term effects.

Development and impact of hooks of high droplet concentration on remote southeast Pacific stratocumulus

NASA Astrophysics Data System (ADS)

George, R. C.; Wood, R.; Bretherton, C. S.; Painter, G.

2013-07-01

Over the southeastern Pacific (SEP), droplet concentration (Nd) in the typically unpolluted marine stratocumulus west of 80° W (> 1000 km offshore) is periodically strongly enhanced in zonally elongated "hook"-shaped features that increase albedo. Here, we examine three hook events using the chemistry version of the Weather Research and Forecasting model (WRF-Chem) with 14 km horizontal resolution, satellite data, and aircraft data from the VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx). A particularly strong hook yields insights into the development, decay, and radiative impact of these features. Hook development occurs with Nd increasing to polluted levels over the remote ocean primarily due to entrainment of cloud condensation nuclei (CCN) from the lower free troposphere (FT). The feature advects northwestward until the FT CCN source is depleted, after which Nd decreases over a few days due to precipitation and dilution. The model suggests that the FT CCN source supplying the hook consists of high concentrations of small accumulation-mode aerosols that contribute a relatively small amount of aerosol mass to the MBL, in agreement with near-coast VOCALS measurements of polluted layers in the FT. The aerosol particles in this hook originate mainly from a pulse of offshore flow that transports Santiago-region (33-35° S) emissions to the remote marine FT. To provide pollution CCN that can sustain hooks, the FT transport of pollution plumes to the remote ocean requires strong, deep offshore flow. Such flow is favored by a trough approaching the South American coast and a southeastward shift of the climatological subtropical high-pressure system. The model simulations show precipitation suppression in the hook and a corresponding increase in liquid water path (LWP) compared with a simulation without anthropogenic sources. LWP also increases as the hook evolves over time due to increasing stability and decreasing subsidence. WRF-Chem suggests that dimethyl sulfide (DMS) significantly influences the aerosol number and size distributions in a hook, but that hooks do not form without FT CCN. The Twomey effect contributes ~ 50-70% of the albedo increase due to the presence of the hook, while secondary aerosol indirect effects and meteorological influences also contribute significantly. The source of hook aerosols is difficult to determine with the available observations alone. The model provides further explanation of the factors influencing hook formation. Two other weaker hooks during VOCALS-REx are not as well simulated but are also associated with FT offshore flow near Santiago. Hooks demonstrate the importance of free-tropospheric transport of aerosols in modulating the droplet concentration in the southeastern Pacific stratocumulus deck, and present a formidable challenge to simulate accurately in large-scale models.

Hooke's figurations: a figural drawing attributed to Robert Hooke.

PubMed

Hunter, Matthew C

2010-09-20

The experimental philosopher Robert Hooke (1635-1703) is known to have apprenticed to the leading painter Peter Lely on his first arrival in London in the late 1640s. Yet the relevance of Hooke's artistic training to his mature draughtsmanship and identity has remained unclear. Shedding light on that larger interpretive problem, this article argues for the attribution to Hooke of a figural drawing now in Tate Britain (T10678). This attributed drawing is especially interesting because it depicts human subjects and bears Hooke's name functioning as an artistic signature, both highly unusual features for his draughtsmanship. From evidence of how this drawing was collected and physically placed alongside images by leading artists in the early eighteenth century, I suggest how it can offer new insight into the reception of Hooke and his graphic work in the early Enlightenment.

Comparative evaluation of apically extruded debris with V-Taper, ProTaper Next, and the Self-adjusting File systems

PubMed Central

Vyavahare, Nishant K.; Raghavendra, Srinidhi Surya; Desai, Niranjan N.

2016-01-01

Background: Complete cleaning of the root canal is the goal for ensuring success in endodontics. Removal of debris plays an important role in achieving this goal. In spite of advancements in instrument design, apical extrusion of debris remains a source of inflammation in the periradicular region. Aim: To comparatively evaluate the amount of apically extruded debris with V-Taper, ProTaper Next, and the self-adjusting File (SAF) system. Materials and Methods: Sixty-four extracted human mandibular teeth with straight root canals were taken. Access openings were done and working length determined. The samples were randomly divided into three groups: Group I - V-Taper files (n = 20), Group II - ProTaper Next (n = 20), Group III - SAF (n = 20). Biomechanical preparation was completed and the debris collected in vials to be quantitatively determined. The data obtained was statistically analyzed using ANOVA and post hoc Tukey's test. Results: All the specimens showed apical debris extrusion. SAF showed significantly less debris extrusion compared to V-Taper and ProTaper Next (P < 0.001). Among Groups I and II, ProTaper Next showed lesser debris extrusion as compared to V-Taper, but it was not significant (P = 0.124). Conclusion: The SAF showed least amount of apical debris extrusion when compared to newer rotary endodontic instruments. This indicates that the incidence of inter-treatment flare-ups due to debris extrusion would be less with the SAF. PMID:27217636

Hooking Up and Identity Development of Female College Students

ERIC Educational Resources Information Center

Kooyman, Leslie; Pierce, Gloria; Zavadil, Amy

2011-01-01

Hooking up generally involves casual sex with noncommittal partners. Hooking up is prevalent on college campuses today and can negatively affect the identity development of female students. The authors examined this phenomenon with a feminist developmental perspective, evaluating hooking up in the context of sexual risk taking with physical and…

21 CFR 868.5420 - Ether hook.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ether hook. 868.5420 Section 868.5420 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5420 Ether hook. (a) Identification. An ether hook is a device...

Floral elaiophores in Lockhartia Hook. (Orchidaceae: Oncidiinae): their distribution, diversity and anatomy

PubMed Central

Blanco, Mario A.; Davies, Kevin L.; Stpiczyńska, Malgorzata; Carlsward, Barbara S.; Ionta, Gretchen M.; Gerlach, Günter

2013-01-01

Background and Aims A significant proportion of orchid species assigned to subtribe Oncidiinae produce floral oil as a food reward that attracts specialized bee pollinators. This oil is produced either by glabrous glands (epithelial elaiophores) or by tufts of secretory hairs (trichomal elaiophores). Although the structure of epithelial elaiophores in the Oncidiinae has been well documented, trichomal elaiophores are less common and have not received as much attention. Only trichomal elaiophores occur in the genus Lockhartia, and their distribution and structure are surveyed here for the first time. Methods Flowers of 16 species of Lockhartia were studied. The location of floral elaiophores was determined histochemically and their anatomical organization and mode of oil secretion was investigated by means of light microscopy, scanning electron microscopy and transmission electron microscopy. Key Results and Conclusions – All species of Lockhartia investigated have trichomal elaiophores on the adaxial surface of the labellum. Histochemical tests revealed the presence of lipoidal substances within the labellar trichomes. However, the degree of oil production and the distribution of trichomes differed between the three major groups of species found within the genus. All trichomes were unicellular and, in some species, of two distinct sizes, the larger being either capitate or apically branched. The trichomal cuticle was lamellate, and often appeared distended due to the subcuticular accumulation of oil. The labellar trichomes of the three species examined using transmission electron microscopy contained dense, intensely staining cytoplasm with apically located vacuoles. Oil-laden secretory vesicles fused with the plasmalemma and discharged their contents. Oil eventually accumulated between the cell wall and cuticle of the trichome and contained electron-transparent profiles or droplets. This condition is considered unique to Lockhartia among those species of elaiophore-bearing Oncidiinae studied to date. PMID:24169595

Removal of a barbed fish hook from the cornea of an 8-year-old boy.

PubMed

Kemp, Pavlina S; Shah, Ankoor S; Elliott, Alexandra T; Wan, Michael J

2017-10-01

This video article shows the surgical removal of a three-pronged barbed fish hook from the cornea and anterior chamber of an 8-year-old boy. The advance-and-cut method is shown: the embedded barbed point of the fish hook was advanced through the cornea, its point was cut off, and the shank of the hook was withdrawn. This method was chosen due to the three-pronged configuration of the fish hook to minimize additional trauma to the eye. Other methods of fish hook removal are briefly reviewed. Copyright © 2017 American Association for Pediatric Ophthalmology and Strabismus. Published by Elsevier Inc. All rights reserved.

The dynamic instability in the hook/flagellum system that triggers bacterial flicks

NASA Astrophysics Data System (ADS)

Jabbarzadeh, Mehdi; Fu, Henry

2017-11-01

Dynamical bending, buckling, and polymorphic transformations of the flagellum are known to affect bacterial motility, but run-reverse-flick motility of monotrichous bacteria also involves the even more flexible hook, which connects the flagellum to the cell body. Here, we identify the dynamic buckling mechanism that produces flicks in Vibrio alginolyticus. Estimates of forces and torques on the hook from experimental observations suggest that flicks are triggered at stresses below the hook's static Euler buckling criterion. Using an accurate linearization of the Kirchoff rod model for the hook in a model of a swimming bacterium with rigid flagellum, we show that as hook stiffness decreases there is a transition from on-axis flagellar rotation with small hook deflections to flagellar precession with large deflections. When flagellum flexibility is incorporated, the precession is disrupted by significant flagellar bending - i.e., incipient flicks. The predicted onset of dynamic instabilities corresponds well with experimentally observed flick events.

Fish hook injury: removal by ''push through and cut off'' technique: a case report and brief literature review.

PubMed

Ahmad Khan, Hayat; Kamal, Younis; Lone, Ansar Ul Haq

2014-04-01

Fishing is a leisure activity for some people around the world. Accidently the fish hook can get hooked in the hand. If the hook is barbed, removal becomes difficult. We report a case of such a injury in the hand and discuss the technique for its removal with a brief review of the literature. A thirty-two year old male accidently suffered a fishhook injury to his hand. He came to the orthopaedic ward two hours after the incident with pain; the fish hook was hanging from the hand. Unsuccessful attempts to remove it were made by his relatives. A push-through and cut-off technique was used for removal of barbed hook. Barbed hooks are to be removed atraumatically with controlled incision over properly anaesthetised skin. Proper wound management and prophylactic antibiotics suitable for treatment of Aeromonas species should be initiated to prevent complications.

Getting Hooked on Physics!

ERIC Educational Resources Information Center

McHugh, M.; McCauley, V.

2016-01-01

A number of papers in this journal have dealt with the idea of using hooks in physics instruction. A hook, as the name suggests, engages students in learning by triggering their attention and interest. Hooks can be any type of pedagogical approach--a question, a demonstration, a puzzle or video. They are generally short and center on the most…

A Pedagogy of Sight: Microscopic Vision in Robert Hooke's "Micrographia"

ERIC Educational Resources Information Center

Jack, Jordynn

2009-01-01

Robert Hooke's "Micrographia" (1665) holds an important place in the history of scientific visual rhetoric. Hooke's accomplishment lies not only in a stunning array of engravings, but also in a "pedagogy of sight"--a rhetorical framework that instructs readers how to view images in accordance with an ideological or epistemic program. Hooke not…

Sidney Hook's Pragmatic Anti-Communism: Commitment to Democracy as Method

ERIC Educational Resources Information Center

Ferriter, Courtney

2017-01-01

In recent years, opposition to Communism has emerged as Sidney Hook's central philosophical legacy in the eyes of scholars and historians, who tend to ignore all of Hook's pre-Cold War philosophical contributions. Furthermore, critics who treat Hook's anti-Communism often accuse him of abandoning pragmatism for dogmatism in his later career. In…

An experimental 'Life' for an experimental life: Richard Waller's biography of Robert Hooke (1705).

PubMed

Moxham, Noah

2016-03-01

Richard Waller's 'Life of Dr Robert Hooke', prefixed to his edition of Hooke's Posthumous Works (1705), is an important source for the life of one of the most eminent members of the early Royal Society. It also has the distinction of being one of the earliest biographies of a man of science to be published in English. I argue that it is in fact the first biography to embrace the subject's natural-philosophical work as the centre of his life, and I investigate Waller's reasons for adopting this strategy and his struggle with the problem of how to represent an early experimental philosopher in print. I suggest that Waller eschews the 'Christian philosopher' tradition of contemporary biography - partly because of the unusually diverse and fragmentary nature of Hooke's intellectual output - and draws instead upon the structure of the Royal Society's archive as a means of organizing and understanding Hooke's life. The most quoted phrase from Waller's biography is that Hooke became 'to a crime close and reserved' in later life; this essay argues that Waller's biographical sketch was fashioned in order to undo the effects of that reserve. In modelling his approach very closely on the structure of the society's records he was principally concerned with making Hooke's work and biography accessible, intelligible and useful to the fellowship in a context familiar to them, a context which had provided the institutional framework for most of Hooke's adult life. I argue that Waller's 'Life' was also intended to make the largest claims for Hooke's intellectual standing that the author dared in the context of the enmity between Hooke and Isaac Newton once the latter became president of the Royal Society. However, I also adduce fresh manuscript evidence that Waller actually compiled, but did not publish, a defence of Hooke's claim to have discovered the inverse square law of gravity, allowing us to glimpse a much more assertive biography of Hooke than the published version.

Arthroscopic Diagnosis of the Triangular Fibrocartilage Complex Foveal Tear: A Cadaver Assessment.

PubMed

Trehan, Samir K; Wall, Lindley B; Calfee, Ryan P; Shen, Tony S; Dy, Christopher J; Yannascoli, Sarah M; Goldfarb, Charles A

2018-01-25

To determine whether the arthroscopic hook and trampoline tests are accurate and reliable diagnostic tests for foveal triangular fibrocartilage complex (TFCC) detachment. Wrist arthroscopy was performed on 10 cadaveric upper extremities. Arthroscopic hook and trampoline tests were performed and videos recorded (baseline). The deep foveal TFCC insertion was then sharply detached. Arthroscopic hook and trampoline tests were repeated. Subsequently, the foveal detachment was repaired via an ulnar tunnel technique and the hook test was repeated for a third time. Videos were independently reviewed at 2 time points by 2 fellowship-trained hand surgeons and 1 hand surgery fellow in a randomized and blinded fashion. Hook and trampoline tests were graded as positive or negative. Proportions of categorical variables were compared via 2-tailed Fisher exact test. Inter- and intraobserver reliabilities were assessed via Cohen kappa coefficient. The sensitivity and specificity of the hook test for foveal detachment diagnosis were 90% and 90%, respectively. There was 90% agreement among all 3 observers for the baseline and foveal detachment hook tests. Cohen kappa coefficients for the inter- and intraobserver reliabilities of the hook test were 0.87 and 0.81, respectively. Seventeen percent of trampoline tests were positive at baseline versus 43% after foveal detachment. The trampoline test had 45% agreement between the 3 observers. Cohen kappa coefficients for the inter- and intraobserver reliabilities of the trampoline test were 0.16 and 0.63, respectively. Following ulnar tunnel repair, 20% of hook tests were positive. The hook test is highly sensitive, specific, and reliable for the diagnosis of isolated TFCC foveal detachment. The trampoline test has insufficient reliability to assess foveal detachment. A TFCC foveal repair using an ulnar tunnel technique returns the hook test to baseline. The hook test is a sensitive, specific, and reliable test for the diagnosis of isolated TFCC foveal detachment. Copyright © 2017 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

MTA apical plugs in the treatment of traumatized immature teeth with large periapical lesions.

PubMed

Cehreli, Zafer C; Sara, Sezgi; Uysal, Serdar; Turgut, Melek D

2011-02-01

This case report describes the management of a late-referral case of periapically involved, traumatized immature permanent incisors by endodontic treatment and the use of mineral trioxide aggregate (MTA) apical plugs. A 10-year-old boy was referred to the clinic with a chief complaint of pain in his maxillary central incisors, which had experienced subluxation trauma 2 years earlier. Periapical radiograph of the teeth showed incomplete root development with wide-open apices and large periradicular lesions. The canals were gently debrided using K-files in conjunction with 2.5% NaOCl irrigation and 2% chlorhexidine for final flush. The root canals became asymptomatic after employing the same endodontic regimen for three visits. MTA plugs were placed in the apical area of the root canals, and the rest of the canal space was obturated by warm compaction of gutta-percha and AH Plus sealer. Resolution of the large periapical lesions was observed 2 months after treatment. At 18 months, the periapical areas revealed radiographic evidence of bone healing. Following successful removal of the toxic content of the root canal, placement of MTA plugs resulted in both healing of the periradicular radiolucency and regeneration of the periapical tissue. © 2010 John Wiley & Sons A/S.

A dynamic model of saliva secretion

PubMed Central

Palk, Laurence; Sneyd, James; Shuttleworth, Trevor J.; Yule, David I.; Crampin, Edmund J.

2010-01-01

We construct a mathematical model of the parotid acinar cell with the aim of investigating how the distribution of K+ and Cl− channels affects saliva production. Secretion of fluid is initiated by Ca2+ signals acting the Ca2+ dependent K+ and Cl− channels. The opening of these channels facilitates the movement of Cl− ions into the lumen which water follows by osmosis. We use recent results into both the release of Ca2+ from internal stores via the inositol (1,4,5)-trisphosphate receptor (IP3R) and IP3 dynamics to create a physiologically realistic Ca2+ model which is able to recreate important experimentally observed behaviours seen in parotid acinar cells. We formulate an equivalent electrical circuit diagram for the movement of ions responsible for water flow which enables us to calculate and include distinct apical and basal membrane potentials to the model. We show that maximum saliva production occurs when a small amount of K+ conductance is located at the apical membrane, with the majority in the basal membrane. The maximum fluid output is found to coincide with a minimum in the apical membrane potential. The traditional model whereby all Cl− channels are located in the apical membrane is shown to be the most efficient Cl− channel distribution. PMID:20600135

An Atypical Variant of Superolateral Dislocation of the Mandibular Condyle: A Case Report.

PubMed

Malik, Kapil; Debnath, Subhas C; Adhyapok, Apurba K; Hazarika, Kriti

2017-10-01

Dislocation of the mandibular condyle from the glenoid fossa can occur in anterior, posterior, lateral, and superior directions. Posterior, lateral, and superior dislocations are rare. Superolateral dislocation is seldom encountered in clinical practice. It is generally associated with fracture of the anterior or contralateral side of the mandible. The occurrence of superolateral dislocation of the condyle hooked above the zygomatic arch with an associated fracture of the medial pole of the condyle is rare and has been reported only once in the literature. This report describes another case in which the patient had superolateral dislocation of the mandibular condyle with a fractured medial pole without any associated fracture of the anterior or contralateral side of the mandible. The condyle was hooked laterally above the zygomatic arch. Open reduction of the dislocated condyle was performed and a good outcome was obtained. Copyright © 2017 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Cut-it-out technique for ocular fish-hook injury.

PubMed

Ahmad, Syed Shoeb; Seng, Chiang Wai; Ghani, Shuaibah Abdul; Lee, Jane F

2013-10-01

An 11-year-old boy was involved in an injury with a fish-hook to his eye. The hook had impaled itself to the cornea and deeper structures. There was associated corneal edema and hyphema, making visualization difficult. In this case, we performed the unusual "cut-it-out" technique to remove the hook from the eye.

String Technique for Anterior Orbital Fish Hook Removal.

PubMed

Starr, Matthew R; Choi, Michael B; Mahr, Michael A; Mettu, Pradeep; Patterson, David F

2018-06-13

Removing fish hooks is a common procedure performed by many emergency department providers. There are several techniques that are commonly employed to aid in successful removal. However, when a fish hook becomes embedded within the orbit, there are limited options as to avoid damaging vital surrounding structures. The authors report the removal of a fish hook within the anterior orbit using the string technique in a 25-year-old patient. The procedure was performed under general anesthesia with the aid of size 5 polyglactin suture wrapped around the hook. The procedure itself took less than 10 seconds and was successful in swiftly and safely removing the hook without damaging surrounding orbital structures. The patient recovered well without any permanent sequelae.

Apical Extrusion of Irrigants in Immature Permanent Teeth by Using EndoVac and Needle Irrigation: An In Vitro Study

PubMed Central

Velmurugan, N; Sooriaprakas, C; Jain, Preetham

2014-01-01

Objective: Immature teeth have a large apical opening and thin divergent or parallel dentinal walls; hence, with conventional needle irrigation there is a very high possibility of extrusion. This study was done to compare the apical extrusion of NaOCl in an immature root delivered using EndoVac and needle irrigation. Materials and Methods: Eighty freshly extracted maxillary central incisors were decoronated followed by access cavity preparation. Modified organotypic protocol was performed to create an open apex; then, the samples were divided into four groups (n=20): EndoVac Microcannula (group I), EndoVac Macrocannula (group II), NaviTip irrigation needle (group III) and Max-i-Probe Irrigating needle (group IV); 9.0 ml of 3% sodium hypochlorite was delivered slowly over a period of 60 seconds. Extruded irrigants were collected in a vial and analysed statistically. Results: Group I, group III and group IV showed 100% extrusion (20/20) but group II showed only 40% extrusion (8/20). The difference in this respect between group II and other groups was statistically significant (P<0.001). With regards to the volume of extrusion, group II had only 0.23 ml of extruded irrigant. Group I extruded 7.53ml of the irrigant. Group III and group IV extruded the entire volume of irrigant delivered. Conclusion: EndoVac Macrocannula resulted in the least extrusion of irrigant in immature teeth when compared to EndoVac Microcannula and conventional needle irrigation. PMID:25584055

Histologic Outcomes of Uninfected Human Immature Teeth Treated with Regenerative Endodontics: 2 Case Reports.

PubMed

Nosrat, Ali; Kolahdouzan, Alireza; Hosseini, Farzaneh; Mehrizi, Ehsan A; Verma, Prashant; Torabinejad, Mahmoud

2015-10-01

A growing body of evidence exists showing the possibility of growing vital tissues in the root canal spaces of teeth with necrotic pulps and open apices. However, there is very limited histologic information regarding characteristics of tissues formed in the root canal space of human teeth after regenerative endodontics. The aim of this study was to examine clinically and histologically the outcomes of human immature teeth treated with regenerative endodontics. Two healthy birooted human maxillary first premolar teeth scheduled for extraction were included. Preoperative radiographs confirmed that these teeth had immature apices. Vitality tests showed the presence of vital pulps in these teeth. After receiving consent forms, the teeth were isolated with a rubber dam, and the pulps were completely removed. After the formation of blood clots in the canals, the teeth were covered with mineral trioxide aggregate. Four months later, the teeth were clinically and radiographically evaluated, extracted, and examined histologically. Both patients remained asymptomatic after treatment. Radiographic examination of the teeth showed signs of root development after treatment. Histologic examination of tissues growing into the root canal space of these teeth shows the presence of connective tissue, bone and cementum formation, and thickening of roots. Based on our findings, it appears that when canals of teeth with open apices are treated with regenerative endodontics, tissues of the periodontium grow into the root canals of these teeth. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Comparison of fracture resistance of simulated immature teeth with an open apex using Biodentine and composite resin: An in vitro study.

PubMed

Zhabuawala, Murtuza Saifuddin; Nadig, Roopa R; Pai, Veena S; Gowda, Yashwanth

2016-01-01

To evaluate the fracture resistance in simulated immature teeth that had been backfilled using composite resin and Biodentine after using Biodentine as an apical plug material immediately and after 3 months of aging. Sixty extracted human maxillary central incisors were simulated in an immature open apex. The roots of all the specimens were then standardized to a length of 10 mm and canals were instrumented to obtain the radicular dentin thickness around 1.5 mm. All the specimens were then randomly divided into three groups of twenty teeth each. Group I (control) - 4 mm apical plug of Biodentine backfilled with thermoplasticized gutta-percha. Group II - 4 mm apical plug of Biodentine and then backfilled with ParaCore. Group III - completely filled with Biodentine. Ten samples from each group were randomly divided into two subgroups. In subgroup A: Specimens were stored for 1 week. In subgroup B: Specimens were stored in phosphate-buffered saline solution for 3 months and were subjected to universal testing machine. Statistical analysis was done using one-way analysis. No significant difference in fracture resistance between the groups was observed when tested immediately. After 3 months of aging, only Biodentine group showed a significant reduction in fracture resistance without significant reduction with other two groups. Biodentine group has shown a drastic reduction in fracture resistance after 3 months of aging, and hence cannot be recommended as a reinforcement material in immature teeth with thin dentin walls.

Hook2 is involved in the morphogenesis of the primary cilium

PubMed Central

Baron Gaillard, Carole L.; Pallesi-Pocachard, Emilie; Massey-Harroche, Dominique; Richard, Fabrice; Arsanto, Jean-Pierre; Chauvin, Jean-Paul; Lecine, Patrick; Krämer, Helmut; Borg, Jean-Paul; Le Bivic, André

2011-01-01

Primary cilia originate from the centrosome and play essential roles in several cellular, developmental, and pathological processes, but the underlying mechanisms of ciliogenesis are not fully understood. Given the involvement of the adaptor protein Hook2 in centrosomal homeostasis and protein transport to pericentrosomal aggresomes, we explored its role in ciliogenesis. We found that in human retinal epithelial cells, Hook2 localizes at the Golgi apparatus and centrosome/basal body, a strategic partitioning for ciliogenesis. Of importance, Hook2 depletion disrupts ciliogenesis at a stage before the formation of the ciliary vesicle at the distal tip of the mother centriole. Using two hybrid and immunoprecipitation assays and a small interfering RNA strategy, we found that Hook2 interacts with and stabilizes pericentriolar material protein 1 (PCM1), which was reported to be essential for the recruitment of Rab8a, a GTPase that is believed to be crucial for membrane transport to the primary cilium. Of interest, GFP::Rab8a coimmunoprecipitates with endogenous Hook2 and PCM1. Finally, GFP::Rab8a can overcome Hook2 depletion, demonstrating a functional interaction between Hook2 and these two important regulators of ciliogenesis. The data indicate that Hook2 interacts with PCM1 in a complex that also contains Rab8a and regulates a limiting step required for further initiation of ciliogenesis after centriole maturation. PMID:21998199

The Topic Is Sandy Hook: A Program for Gifted and Talented Students at Sandy Hook.

ERIC Educational Resources Information Center

Grant, David

"The Topic Is Sandy Hook" is an experiential 10-week program designed to provide special opportunities and educational experiences for 6th to 10th grade gifted and talented students. Sandy Hook, a natural resource in Monmouth County, New Jersey, is unique in its physical and historical features and provides an exceptionally rich environment in…

49 CFR 393.134 - What are the rules for securing roll-on/roll-off or hook lift containers?

Code of Federal Regulations, 2011 CFR

2011-10-01

... or hook lift containers? 393.134 Section 393.134 Transportation Other Regulations Relating to... for securing roll-on/roll-off or hook lift containers? (a) Applicability. The rules in this section apply to the transportation of roll-on/roll-off or hook lift containers. (b) Securement of a roll-on...

49 CFR 393.134 - What are the rules for securing roll-on/roll-off or hook lift containers?

Code of Federal Regulations, 2010 CFR

2010-10-01

... or hook lift containers? 393.134 Section 393.134 Transportation Other Regulations Relating to... for securing roll-on/roll-off or hook lift containers? (a) Applicability. The rules in this section apply to the transportation of roll-on/roll-off or hook lift containers. (b) Securement of a roll-on...

Education as a Practice of Freedom: Reflections on bell hooks

ERIC Educational Resources Information Center

Specia, Akello; Osman, Ahmed A.

2015-01-01

This paper critically analyses the conceptions of bell hooks on education. It focuses on the relevance of hook's ideas to the classroom. It is a theoretical paper based on secondary data that seeks to contribute to the growing body of knowledge in education. The paper is a reflection of hook's reaction to education as a practice of freedom, the…

The Relationship Between Perceived Hookup Attitudes and Negative Hookup Consequences: Do Perceived Attitudes of Close Friends Matter?

PubMed

Montes, Kevin S; Blanco, Lyzette; LaBrie, Joseph W

2017-01-01

Research suggests that the perceived hookup attitudes of close referents are generally a poor predictor of hookup behavior and likely a poor direct predictor of negative hookup consequences. The current study aimed to examine three intervening variables as mediators of the relationship between the perceived hookup attitudes of college students' close friends and negative hookup consequences (e.g., regret, embarrassment). Self-report data were collected from 589 heavy-drinking college students from three midsized universities. The results indicated that students' own attitudes toward hooking up, motivation to hook up, and self-reported number of hookup partners significantly mediated the relationship between the perceived hookup attitudes of close friends and negative hookup consequences. The perceived hookup attitudes of close friends were positively associated with participants' attitudes toward hooking up. Participants' attitudes toward hooking up were positively associated with social-sexual motivation to hook up. Elevated social-sexual motivation to hook up was positively associated with hooking up with multiple partners, with hooking up with multiple partners positively associated with negative hookup consequences. A better understanding of the predictors and mediators of negative hookup consequences has the potential to inform prevention and intervention efforts.

Archeological Survey and Testing Along Boone Creek, Louisiana Army Ammunition Plant, Webster Parish, Louisiana

DTIC Science & Technology

1989-01-01

ducks, partridges, cranes , quail, snakes, and fish. 8 CHAPTER 2: ENVIRONMENTAL SETTING Climate The modern climate of the project area is classified as... caustic materials. Large openings in their sides were cut by oil field workers, who then added water to the dry caustic material to make a caustic ...whiffletree hook and a harness ring were recovered, indicating that horses were used here. No automotive artifacts were recovered. This again reinforces the

[Comparison between J-hook and micro-implant anchorage in the treatment of patients with bimaxillary protrusion].

PubMed

Chen, Wen-Jing; Li, Qing-Yi; Gong, Ai-Xiu; Hu, Fang; Gu, Yong-Jia

2008-02-01

To compare the difference between J-hook and micro-implant anchorage in the treatment of patient with bimaxillary protrusion. Thirty patients with bimaxillary protrusion were divided into two groups (J-hook and micro-implant groups) and treated with MBT appliance. Four first premolars were extracted in all patients. Cephalometric analyses were carried out before and after treatment. In J-hook group and micro-implant group,computerized cephalometric analysis revealed that before treatment U6C-PP was (12.4 +/- 0.2) mm and (12.5 +/- 0.1) mm, respectively,and after treatment U6C-PP was (12.6 +/- 0.1) mm and (12.8 +/- 0.1) mm,respectively. The difference between J-hook group and microimplant group was significant (P < 0.01). The other differences of cephalometric analyses between J-hook group and micro-implant group was not significant. Both J-hook and micro-implant could provide adequate anchorage in the treatment of patients with bimaxillary protrusion.

Designing physics video hooks for science students

NASA Astrophysics Data System (ADS)

McHugh, M.; McCauley, V.

2016-01-01

This paper offers an insight into the design structure of physics video hooks that were developed by the Science Education Resource design team in the school of education (SOE) in National University of Ireland, Galway (NUI Galway). A hook, is an instructional technique used to stimulate student attention (Hunter 1994, Lemov 2010), interest (Jewett 2013) and engagement (McCrory 2011, Riendeau 2013). The physics video hooks followed a design framework that is illustrated below by breaking down the centre of gravity (COG) hook. Various design principles and elements embedded within the COG hook are presented with examples and the time they occur within the video. The intention of this article is that the design can be replicated and modified to aid teachers and designers in the development of a multitude of classroom based multimedia resources.

SUPPRESSOR OF APICAL DOMINANCE1 of Sporisorium reilianum Modulates Inflorescence Branching Architecture in Maize and Arabidopsis1[OPEN

PubMed Central

Ghareeb, Hassan; Löfke, Christian; Teichmann, Thomas; Schirawski, Jan

2015-01-01

The biotrophic fungus Sporisorium reilianum causes head smut of maize (Zea mays) after systemic plant colonization. Symptoms include the formation of multiple female inflorescences at subapical nodes of the stalk because of loss of apical dominance. By deletion analysis of cluster 19-1, the largest genomic divergence cluster in S. reilianum, we identified a secreted fungal effector responsible for S. reilianum-induced loss of apical dominance, which we named SUPPRESSOR OF APICAL DOMINANCE1 (SAD1). SAD1 transcript levels were highly up-regulated during biotrophic fungal growth in all infected plant tissues. SAD1-green fluorescent protein fusion proteins expressed by recombinant S. reilianum localized to the extracellular hyphal space. Transgenic Arabidopsis (Arabidopsis thaliana)-expressing green fluorescent protein-SAD1 displayed an increased number of secondary rosette-leaf branches. This suggests that SAD1 manipulates inflorescence branching architecture in maize and Arabidopsis through a conserved pathway. Using a yeast (Saccharomyces cerevisiae) two-hybrid library of S. reilianum-infected maize tissues, we identified potential plant interaction partners that had a predicted function in ubiquitination, signaling, and nuclear processes. Presence of SAD1 led to an increase of the transcript levels of the auxin transporter PIN-FORMED1 in the root and a reduction of the branching regulator TEOSINTE BRANCHED1 in the stalk. This indicates a role of SAD1 in regulation of apical dominance by modulation of branching through increasing transcript levels of the auxin transporter PIN1 and derepression of bud outgrowth. PMID:26511912

78 FR 23864 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using Hook...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-23

... Catcher/Processors Using Hook-and-line Gear in the Western Regulatory Area of the Gulf of Alaska AGENCY.../processors (C/Ps) using hook-and-line gear in the Western Regulatory Area of the Gulf of Alaska (GOA). This... catch apportioned to C/Ps using hook-and-line gear in the Western Regulatory Area of the GOA. DATES...

77 FR 11776 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using Hook...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-28

.../Processors Using Hook-and-Line Gear in the Central Regulatory Area of the Gulf of Alaska AGENCY: National... (C/Ps) using hook-and-line gear in the Central Regulatory Area of the Gulf of Alaska (GOA). This... catch apportioned to C/Ps using hook-and-line gear in the Central Regulatory Area of the GOA. DATES...

Morphological analysis of acromion and hook plate for the fixation of acromioclavicular joint dislocation.

PubMed

Yoon, Jong Pil; Lee, Yeon Soo; Song, Geun Soo; Oh, Joo Han

2017-03-01

Acromioclavicular (AC) joint dislocation is a common sports injury. Hook plate fixation is currently widely used to treat this injury, as it can promote the natural healing of the ligament with good clinical outcomes. However, subacromial erosion and impingement are frequently observed post-operatively. It was hypothesized that the morphology and the contact characteristics between the hook portion and the acromion are the main causes of complications after hook plate fixation with the currently available commercial designs. Three-dimensional reconstructed models of the AC joint obtained from the computed tomographic scans of 23 male and 23 female patients (mean age, 61.1 ± 6.3 years) were evaluated, and multiple anatomical parameters were measured. For the subacromial positioning of the hook plate, an actual hook plate (Synthes Inc., West Chester, PA, USA) was scanned, and the contact between the hook plate and the acromion was estimated. The thicknesses of the acromion and distal clavicle were 9.7 ± 1.5 mm (10.7 mm in men; 8.6 mm in women) and 11.3 ± 1.6 mm (11.6 mm in men; 10.0 mm in women), respectively. The width of the acromion was 28.5 ± 3.6 mm. The mean inclination angle between the hook plate and the acromion was 29.3° ± 9.7° (27.9° in men; 30.6° in women). The hook plate made a point contact with the acromion at 9.2 ± 3.3 mm (31.5 %) from the lateral end of the acromion. The results revealed that the hook made a pinpoint contact with the undersurface of the acromion, and this might explain why complications commonly occur after hook plate fixation. The force concentration phenomenon associated with the hook plate of existing designs results from cases of morphological mismatch, such as excessive inclination and improper occupation of the subacromial space.

Preventing distal pullout of posterior spine instrumentation in thoracic hyperkyphosis: a biomechanical analysis.

PubMed

Sun, Edward; Alkalay, Ron; Vader, David; Snyder, Brian D

2009-06-01

An in vitro biomechanical study. Compare the mechanical behavior of 5 different constructs used to terminate dual-rod posterior spinal instrumentation in resisting forward flexion moment. Failure of the distal fixation construct can be a significant problem for patients undergoing surgical treatment for thoracic hyperkyphosis. We hypothesize that augmenting distal pedicle screws with infralaminar hooks or sublaminar cables significantly increases the strength and stiffness of these constructs. Thirty-seven thoracolumbar (T12 to L2) calf spines were implanted with 5 configurations of distal constructs: (1) infralaminar hooks, (2) sublaminar cables, (3) pedicle screws, (4) pedicle screws+infralaminar hooks, and (5) pedicle screws+sublaminar cables. Progressive bending moment was applied to each construct until failure. The mode of failure was noted and the construct's stiffness and failure load determined from the load-displacement curves. Bone density and vertebral dimensions were equivalent among the groups (F=0.1 to 0.9, P>0.05). One-way analysis of covariance (adjusted for differences in density and vertebral dimension) demonstrated that all of the screw-constructs (screw, screw+hook, and screw+cable) exhibited significantly higher stiffness and ultimate failure loads compared with either sublaminar hook or cable alone (P<0.05). The screw+hook constructs (109+/-11 Nm/mm) were significantly stiffer than either screws alone (88+/-17 Nm/mm) or screw+cable (98+/-13 Nm/mm) constructs, P<0.05. Screw+cable construct exhibited significantly higher failure load (1336+/-328 N) compared with screw constructs (1102+/-256 N, P<0.05), whereas not statistically different from the screw+hook construct (1220+/-75 N). The cable and hook constructs failed by laminar fracture, screw construct failed in uniaxial shear (pullout), whereas the screws+(hooks or wires) failed by fracture of caudal vertebral body. Posterior dual rod constructs fixed distally using pedicle screws were stiffer and stronger in resisting forward flexion compared with cables or hooks alone. Augmenting these screws with either infralaminar hooks or sublaminar cables provided additional resistance to failure.

Insulin activates single amiloride-blockable Na channels in a distal nephron cell line (A6).

PubMed

Marunaka, Y; Hagiwara, N; Tohda, H

1992-09-01

Using the patch-clamp technique, we studied the effect of insulin on an amiloride-blockable Na channel in the apical membrane of a distal nephron cell line (A6) cultured on permeable collagen films for 10-14 days. NPo (N, number of channels per patch membrane; Po, average value of open probability of individual channels in the patch) under baseline conditions was 0.88 +/- 0.12 (SE)(n = 17). After making cell-attached patches on the apical membrane which contained Na channels, insulin (1 mU/ml) was applied to the serosal bath. While maintaining the cell-attached patch, NPo significantly increased to 1.48 +/- 0.19 (n = 17; P less than 0.001) after 5-10 min of insulin application. The open probability of Na channels was 0.39 +/- 0.01 (n = 38) under baseline condition, and increased to 0.66 +/- 0.03 (n = 38, P less than 0.001) after addition of insulin. The baseline single-channel conductance was 4pS, and neither the single-channel conductance nor the current-voltage relationship was significantly changed by insulin. These results indicate that insulin increases Na absorption in the distal nephron by increasing the open probability of the amiloride-blockable Na channel.

A method to generate the surface cell layer of the 3D virtual shoot apex from apical initials.

PubMed

Kucypera, Krzysztof; Lipowczan, Marcin; Piekarska-Stachowiak, Anna; Nakielski, Jerzy

2017-01-01

The development of cell pattern in the surface cell layer of the shoot apex can be investigated in vivo by use of a time-lapse confocal images, showing naked meristem in 3D in successive times. However, how this layer is originated from apical initials and develops as a result of growth and divisions of their descendants, remains unknown. This is an open area for computer modelling. A method to generate the surface cell layer is presented on the example of the 3D paraboloidal shoot apical dome. In the used model the layer originates from three apical initials that meet at the dome summit and develops through growth and cell divisions under the isotropic surface growth, defined by the growth tensor. The cells, which are described by polyhedrons, divide anticlinally with the smallest division plane that passes depending on the used mode through the cell center, or the point found randomly near this center. The formation of the surface cell pattern is described with the attention being paid to activity of the apical initials and fates of their descendants. The computer generated surface layer that included about 350 cells required about 1200 divisions of the apical initials and their derivatives. The derivatives were arranged into three more or less equal clonal sectors composed of cellular clones at different age. Each apical initial renewed itself 7-8 times to produce the sector. In the shape and location and the cellular clones the following divisions of the initial were manifested. The application of the random factor resulted in more realistic cell pattern in comparison to the pure mode. The cell divisions were analyzed statistically on the top view. When all of the division walls were considered, their angular distribution was uniform, whereas in the distribution that was limited to apical initials only, some preferences related to their arrangement at the dome summit were observed. The realistic surface cell pattern was obtained. The present method is a useful tool to generate surface cell layer, study activity of initial cells and their derivatives, and how cell expansion and division are coordinated during growth. We expect its further application to clarify the question of a number and permanence or impermanence of initial cells, and possible relationship between their shape and oriented divisions, both on the ground of the growth tensor approach.

Influence of hook position on phototropic and gravitropic curvature by etiolated hypocotyls of Arabidopsis thaliana

NASA Technical Reports Server (NTRS)

Khurana, J. P.; Best, T. R.; Poff, K. L.

1989-01-01

Phototropic and gravitropic curvature by hypocotyls of Arabidopsis thaliana is minimal when the side of the hook with the cotyledons attached is positioned toward the direction of tropistic curvature, and maximal when that side of the hook is positioned away from the direction of tropistic curvature. Based on these data, it is proposed that the position of the hook with attached cotyledons affects curvature and not stimulus perception. A randomly oriented population of plants exhibited considerable heterogeneity in tropistic curvature. This heterogeneity arises at least in part from the dependence of curvature on the position of the hook.

Influence of hook position on phototropic and gravitropic curvature by etiolated hypocotyls of Arabidopsis thaliana.

PubMed

Khurana, J P; Best, T R; Poff, K L

1989-01-01

Phototropic and gravitropic curvature by hypocotyls of Arabidopsis thaliana is minimal when the side of the hook with the cotyledons attached is positioned toward the direction of tropistic curvature, and maximal when that side of the hook is positioned away from the direction of tropistic curvature. Based on these data, it is proposed that the position of the hook with attached cotyledons affects curvature and not stimulus perception. A randomly oriented population of plants exhibited considerable heterogeneity in tropistic curvature. This heterogeneity arises at least in part from the dependence of curvature on the position of the hook.

Study on The Geopolymer Concrete Properties Reinforced with Hooked Steel Fiber

NASA Astrophysics Data System (ADS)

Abdullah, M. M. A. B.; Tahir, M. F. M.; Tajudin, M. A. F. M. A.; Ekaputri, J. J.; Bayuaji, R.; Khatim, N. A. M.

2017-11-01

In this research, Class F fly ash and a mixture of alkaline activators and different amount of hooked steel fiber were used for preparing geopolymer concrete. In order to analyses the effect of hooked steel fiber on the geopolymer concrete, the analysis such as chemical composition of fly ash, workability of fresh geopolymer, water absorption, density, compressive strength of hardened geopolymer concrete have been carried out. Mixtures were prepared with fly ash to alkaline liquid ratio of 2.0 with hooked steel fibers were added to the mix with different amounts which are 1%, 3%, 5% and 7% by the weight of the concrete. Experimental results showed that the compressive strength of geopolymer concrete increases as the hooked steel fibers increases. The optimum compressive strength obtained was up to 87.83 MPa on the 14th day. The density of geopolymer concrete are in the range between 2466 kg/m3 to 2501 kg/m3. In addition, the workability value of geopolymer without hooked steel fibers is 100 mm while the workability value of geopolymer with hooked steel fibers are between 60 mm to 30 mm.

Exercises in anatomy: holes between the ventricles.

PubMed

Anderson, Robert H; Sarwark, Anne E; Spicer, Diane E; Backer, Carl L

2014-01-01

Holes between the ventricles are the commonest congenital cardiac malformations. As yet, however, there is no consensus as to how they can best be described and categorized. In this, our third exercise in cardiac anatomy, we address the issue of classification of ventricular septal defects. We begin our demonstration by analysing the normal heart. We show that the larger part of the ventricular septum is made up of its muscular component. The membranous part accounts for only a small portion, which is located centrally within the cardiac base. This small membranous part forms a boundary between the right-sided chambers and the aortic root. Holes at this site, therefore, which account for the commonest defects closed surgically, will open centrally in the cardiac base, being located postero-inferiorly relative to the supraventricular crest. We then show that the larger part of the crest itself is a free-standing muscular sleeve, which lifts the leaflets of the pulmonary valve away from the cardiac base. Only a very small part of the muscle forming the right ventricular outlet is located in the septal position. Turning our attention to malformed hearts, we show how holes between the ventricles can open centrally at the cardiac base, open to the inlet or outlet of the right ventricle or open within the substance of the apical muscular septum. We demonstrate, however, that description of such geographical location of the defects does not paint the full picture, since lesions with markedly different phenotypic features can open in comparable geographic locations. We illustrate how it is the phenotypic features, as seen from the right ventricle, which convey the crucial information for the surgeon with regard to the location of the atrioventricular conduction axis, using hearts with holes opening to the inlet of the right ventricle with muscular as opposed to partially fibrous borders to emphasize this point. We continue by showing how holes with different phenotypes can also open to the outlet of the right ventricle, the key feature in this regard being malalignment between the apical muscular septum relative to the muscular outlet septum or its fibrous remnant. Malalignment can also be found between the apical ventricular septum and the atrial septum, this being shown in a defect opening to the inlet of the right ventricle. We conclude by emphasizing that, so as to bring together all the information of surgical significance, it is necessary to take note of the geographical location of holes between the ventricles, their phenotypic features and the presence or absence of malalignment between the septal components. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Autologus Platelet Rich Fibrin aided Revascularization of an immature, non-vital permanent tooth with apical periodontitis: A case report.

PubMed

Jadhav, Ganesh Ranganath; Shah, Dipali; Raghvendra, Srinidhi Surya

2015-01-01

Caries or trauma induced non-vital immature permanent tooth with blunderbuss, thin root which are very common among childrens are corrected using regenerative endodontic (revascularization) procedures. In the presented case, a 16-year-old boy reported with chief complaint of pain in maxillary left central incisor (Tooth #21). Tooth #21 showed grade III mobility, draining labial sinus, and short blunderbuss root with diffuse periapical radiolucency. Patient was explained the treatment plan and written informed consent was taken. Platelet rich fibrin (PRF) was prepared according to standard protocol. Autologous PRF was carried to the apical portion of the root canal after inducing revascularization. Access opening was double sealed with MTA and resin modified glass ionomer cement (RMGI). Baseline, 12 month and 18 month follow-up intraoral radiographs were taken. Clinically case was asymptomatic with complete resolution of intraoral sinus. Periapical healing, apical closure, root lengthening and dentinal wall thickening were uneventful. Thus PRF supplementation hastens the predictability and rate of revascularization in non-vital immature permanent teeth.

Attempted Recovery of Mercury spacecraft at end of MR-4 mission

NASA Image and Video Library

1961-07-21

S61-02826 (21 July 1961) --- A U.S. Marine Corps helicopter attempts an unsuccessful recovery of the Mercury-Redstone 4 "Liberty Bell 7" spacecraft. The spacecraft hatch opened prematurely, and astronaut Virgil I. Grissom, pilot, escaped into the water. The helicopter hooked onto the spacecraft but could not retrieve it. Grissom was recovered by another helicopter and flown to the recovery ship, USS Randolph. The Mercury spacecraft sank to the bottom of the ocean. Photo credit: NASA

Attempted Recovery of Mercury spacecraft at end of MR-4 mission

NASA Image and Video Library

1961-07-21

S61-02824 (21 July 1961) --- A U.S. Marine Corps helicopter attempts an unsuccessful recovery of the Mercury-Redstone 4 "Liberty Bell 7" spacecraft. The spacecraft hatch opened prematurely, and astronaut Virgil I. Grissom, pilot, escaped into the water. The helicopter hooked onto the spacecraft but could not retrieve it. Grissom was recovered by another helicopter and flown to the recovery ship, USS Randolph. The Mercury spacecraft sank to the bottom of the ocean. Photo credit: NASA

46 CFR 173.007 - Location of the hook load.

Code of Federal Regulations, 2010 CFR

2010-10-01

... PERTAINING TO VESSEL USE Lifting § 173.007 Location of the hook load. When doing the calculations required in this subpart, the hook load must be considered to be located at the head of the crane. ...

Prevalence of Ingested Fish Hooks in Freshwater Turtles from Five Rivers in the Southeastern United States

PubMed Central

Steen, David A.; Hopkins, Brittney C.; Van Dyke, James U.; Hopkins, William A.

2014-01-01

Freshwater turtles may ingest baited fish hooks because many are opportunistic scavengers. Although the ingestion of fish hooks is known to be a source of mortality in multiple vertebrate groups, the prevalence of hook ingestion by freshwater turtles has not been well studied. We trapped turtles from five rivers in the southeastern United States and used radiographs to examine over 600 individuals of four species. Depending on the species, sex, and age class, 0–33% of turtles contained ingested fish hooks. For some species, larger turtles were more likely to contain a fish hook than smaller individuals. Freshwater turtle demography suggests that even small increases in adult mortality may lead to population declines. If our study areas are representative of other aquatic systems that receive fishing pressure, this work likely identifies a potential conflict between a widespread, common recreational activity (i.e., fishing) and an imperiled taxonomic group. PMID:24621919

Cooling system for three hook ring segment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Campbell, Christian X.; Eng, Darryl; Lee, Ching-Pang

2014-08-26

A triple hook ring segment including forward, midsection and aft mounting hooks for engagement with respective hangers formed on a ring segment carrier for supporting a ring segment panel, and defining a forward high pressure chamber and an aft low pressure chamber on opposing sides of the midsection mounting hook. An isolation plate is provided on the aft side of the midsection mounting hook to form an isolation chamber between the aft low pressure chamber and the ring segment panel. High pressure air is supplied to the forward chamber and flows to the isolation chamber through crossover passages in themore » midsection hook. The isolation chamber provides convection cooling air to an aft portion of the ring segment panel and enables a reduction of air pressure in the aft low pressure chamber to reduce leakage flow of cooling air from the ring segment.« less

Thunderstorm-scale variations of echoes associated with left-turn tornado families

NASA Technical Reports Server (NTRS)

Forbes, G. S.

1977-01-01

The origin of tornadoes is studied on the basis of changing radar echo shapes and tornado location relative to the echoes. Three types of tornadoes appear to be associated with different hook echo configurations. No-turn or right-turn tornadoes are linked to a steady hook which does not change shape or orientation. Left-turn tornado families are generated in cases where the hook is unsteady and changes orientation at each successive tornado birth. Finally, left-turn tornado families may also be formed when the hook undergoes no orientation change and the tornadoes move along the rear of the hook. The correlation between a thunderstorm-scale cycle and periodic tornado production is also discussed.

Eight new species of Oragua Melichar, 1926 (Insecta: Hemiptera: Cicadellidae) from Amazonas State, Brazil, with description of the female terminalia of Oragua jurua Young, 1977, and new records for the genus.

PubMed

Camisão, Beatriz M; Cavichioli, Rodney R; Takiya, Daniela M

2014-07-29

The thirty known species of Oragua are distributed from southern Mexico to Argentina. Seventeen species are recorded from Brazil, but only O. elegantula Young, 1977, O. insipida Young, 1977, and O. jurua Young, 1977 are recorded from Amazonas State. Oragua partitula (Jacobi, 1905) is herein firstly recorded from Brazil, ocurring in Amazonas State. The aim of the study was to describe eight new species of Oragua, to provide a key to males of the species of the genus that are recorded from Amazonas State and to study in detail the female terminalia of these new species. Also, the female of O. jurua Young, 1977 is herein described for the first time. Oragua alerochae sp. nov. has the external color pattern similar to O. bifasciata Cavichioli, 2000, however, the head is darker, the forewings are paler and the stripes are thinner, aedeagus is much more curved with long apical processes, and apex of paraphyses rami are curved. Oragua aurantimaculata sp. nov. is similar externally to O. elegantula and Oragua jau sp. nov. as they share the body brown with three orange maculae on crown and orange maculae on forewings, but it has the aedeagus with shaft enlarged medially with a pair of apical processes curved anteriorly and connective more slender. Oragua bella sp. nov. is dark with orange spots, aedeagus with basal elongated processes extending to the apex of the pygofer, with the basal portion enlarged and narrowing toward the apex. Oragua copiosa sp. nov. is dark with small pale dots all over the body, paraphyses rami are slender and their apices expanded, and styles with hooked apex, extending posteriorly beyond the connective apex. Oragua gracilenta sp. nov. has the external color similar to O. galerula, but it can be distinguished by the brown ground color, absence of two maculae near median line just before posterior margin on pronotum and apex of rami of paraphyses bifurcate and not truncate. Oragua jau sp. nov. has the external color similar to O. elegantula, but the aedeagus is curved and slender with a pair of small lateral processes at the apex and very thin paraphyses rami bifurcating only in the final portion, with the length of the rami just one third of the total length. Oragua schwertineri sp. nov. has the external color similar to O. insipida, however the male genitalia differs from the latter by the lack of paraphyses and aedeagus with pair of basal processes curved dorsally and shaft with pair of apical lateral processes. Oragua unifasciata sp. nov. is dark brown with pale spots over the body with a pale transverse stripe over the anteapical cells and paraphyses stem slender and abruptly broadened at apical two thirds, with rami robust and flattened with posterior margin serrate with large and irregular tooth-like projections. This work raises the number of Oragua species occurring in Amazonas State from three to twelve. 

Sandy Hook : alternative access concept plan and vehicle replacement study

DOT National Transportation Integrated Search

2009-06-01

This study addresses two critical issues of concern to the Sandy Hook Unit of Gateway National : Recreational Area: (1) options for alternative access to Sandy Hook during peak summer season, : particularly when the park is closed to private vehicles...

Use of the S-hook for Pelvic Fixation in Rib-Based Treatment of Early-Onset Scoliosis: A Multicenter Study.

PubMed

Ramirez, Norman; Flynn, John M; Smith, John T; Vitale, Michael; Sturm, Peter F; DʼAmato, Charles; Samdani, Amer; Machiavelli, Raul; El-Hawary, Ron

2015-06-01

Retrospective review. The purpose of this study was to evaluate how several preoperative variables affect the outcome using the rib-to-pelvis S-hook constructs of a rib-based distraction implant (Vertical Expandable Prosthetic Titanium Rib). Rib-to-pelvis fixation with S-hooks is one of the options for distal anchoring of rib-based distraction growing rod construct to control early-onset spinal deformity. Since the initial report, the indications of pelvic fixation with S-hooks have been extended and modified. This is an institutional review board-approved retrospective study of patients who underwent rib-based growing rod system surgery-rib-to-pelvis construct with Dunn-McCarthy S-hook. Data evaluation included history, physical examination, preoperative and postoperative radiographs, surgical variables, and complications. Sixty-five patients were evaluated; 38 were male and 27 were female. Mean age at initial procedure was 71 months. The mean follow-up was 46 months. There was a statistically significant improvement of the immediate postoperative Cobb angle and the last follow-up Cobb angle (P < 0.0001). Fifty percent of the patients (32/65) had S-hook-related complications. The most common complication was sliding of the S-hook out of the iliac crest, followed by infection, neuropathic pain, distal migration of more than 2 cm, fracture of the hook, and bursitis. The complications were related to the preoperative ambulatory status, the use of end-to-end rod connectors, surgical time, and not positioning the hook over the central one-third of the iliac crest at the initial implantation. The use of the S-hook as a pelvic attachment of the rib-based system is indicated in nonambulatory patients with progressive, early-onset scoliosis curve with a lack of adequate anchor at the lumbar spine. Several technical factors should be considered to reduce the complication rate. 3.

Trypanorhynch cestodes (Eutetrarhynchidae) from batoids along the coast of Argentina, including the description of new species in Dollfusiella Campbell et Beveridge, 1994 and Mecistobothrium Heinz et Dailey, 1974.

PubMed

Menoret, Adriana; Ivanov, Veronica A

2015-09-07

During a recent parasitological survey of elasmobranchs along the coast of Argentina, two new species of eutetrarhynchid cestodes of the genera Dollfusiella Campbell et Beveridge, 1994 and Mecistobothrium Heinz et Dailey, 1974 were collected from batoids. Dollfusiella acuta sp. n. was found in four arhynchobatid skates, i.e. Sympterygia acuta Garman (type host), Sympterygia bonapartii Müller et Henle, Atlantoraja castelnaui (Miranda Ribeiro) and Atlantoraja platana (Günther), and Mecistobothrium oblongum sp. n. in the eagle ray Myliobatis goodei Garman. Dollfusiella acuta sp. n. has a tentacular armature consisting of basal rows of uncinate hooks, a distinct basal swelling with uncinate, falcate and bill hooks, and a heteroacanthous metabasal armature with heteromorphous hooks (bothrial uncinate hooks and antibothrial falcate hooks), hooks 1(1') not separated, testes in two columns and an internal seminal vesicle. The tentacular armature of M. oblongum sp. n. is characterised by basal rows of uncinate hooks, a basal swelling with uncinate and falcate hooks, a typical heteroacanthous metabasal armature with heteromorphous hooks (uncinate and falcate to spiniform), and hooks 1(1') separated and of a constant size along the tentacle. It also possesses an elongate scolex, numerous testes arranged in 5-6 irregular columns, and an internal seminal vesicle. The discovery of M. oblongum in M. goodei represents the first record of species of Mecistobothrium in the southwestern Atlantic Ocean. An amended description of Dollfusiella cortezensis (Friggens et Duszynski, 2005) is also provided to clarify details of the scolex and tentacular armature. Members of Dollfusiella in the southwestern Atlantic are specific to a single host species or to a particular host family, while M. oblongum was found in a single host species. Although globally some plerocerci of eutetrarhynchids have been found in teleosts, extensive examination of teleosts off the coast of Argentina suggests that the transmission pathways of these species are exclusively based on invertebrates as intermediate or paratenic hosts.

Flagellar Hook Flexibility Is Essential for Bundle Formation in Swimming Escherichia coli Cells

PubMed Central

Brown, Mostyn T.; Steel, Bradley C.; Silvestrin, Claudio; Wilkinson, David A.; Delalez, Nicolas J.; Lumb, Craig N.; Obara, Boguslaw; Berry, Richard M.

2012-01-01

Swimming Escherichia coli cells are propelled by the rotary motion of their flagellar filaments. In the normal swimming pattern, filaments positioned randomly over the cell form a bundle at the posterior pole. It has long been assumed that the hook functions as a universal joint, transmitting rotation on the motor axis through up to ∼90° to the filament in the bundle. Structural models of the hook have revealed how its flexibility is expected to arise from dynamic changes in the distance between monomers in the helical lattice. In particular, each of the 11 protofilaments that comprise the hook is predicted to cycle between short and long forms, corresponding to the inside and outside of the curved hook, once each revolution of the motor when the hook is acting as a universal joint. To test this, we genetically modified the hook so that it could be stiffened by binding streptavidin to biotinylated monomers, impeding their motion relative to each other. We found that impeding the action of the universal joint resulted in atypical swimming behavior as a consequence of disrupted bundle formation, in agreement with the universal joint model. PMID:22522898

Evaluation in vitro of the tensile strength of crimpable hooks used for stabilization in orthognathic surgery.

PubMed

Andrade Gomes, Nascimento Leonard Euller; Melo, Pithon Matheus; Lacerda, Santos Rogério; D'Albuquerque, Medeiros Paulo Jose

2012-03-01

The aim of this study was to evaluate the tensile strength of crimpable hooks used for arch stabilization in orthognatic surgery. Ninety stainless steel wire (0.019" × 0.026") segments, each measuring 6 cm long, were used and attached to crimpable hooks of different commercial brands. Six groups were formed (n = 10) denominated as follows: control, in which the wire segments were perpendicularly welded by spot welding machine; and the hooks groups M (Morelli), MS (Morelli with weld), TP (TP Ortho), TPS (TP with weld), TPTg (TP-tungsten), TPTgS (TP-tungsten with weld), AO (American Orthodontics), and AOS (American Orthodontics with weld). The test specimen topography was evaluated by scanning electron microscopy before and after the tensile strength tests. After obtaining the results, the analysis of variance and Kruskal-Wallis multiple-comparison tests were applied. Compared with the control group, the AOS ball hooks and those from TPS required a greater amount of force to be displaced along the rectangular arch. The hooks in group M were significantly easier to displace, followed by those from AO. The best ball hooks for clinical application are those from AOS and TPS. Copyright © 2012 Elsevier Inc. All rights reserved.

Hierarchical protein export mechanism of the bacterial flagellar type III protein export apparatus.

PubMed

Minamino, Tohru

2018-06-01

The bacterial flagellum is supramolecular motility machinery consisting of the basal body, the hook and the filament. Flagellar proteins are translocated across the cytoplasmic membrane via a type III protein export apparatus, diffuse down the central channel of the growing structure and assemble at the distal end. Flagellar assembly begins with the basal body, followed by the hook and finally the filament. The completion of hook assembly is the most important morphological checkpoint of the sequential flagellar assembly process. When the hook reaches its mature length of about 55 nm in Salmonella enterica, the type III protein export apparatus switches export specificity from proteins required for the structure and assembly of the hook to those responsible for filament assembly, thereby terminating hook assembly and initiating filament assembly. Three flagellar proteins, namely FliK, FlhB and FlhA, are responsible for this substrate specificity switching. Upon completion of the switching event, interactions among FlhA, the cytoplasmic ATPase complex and flagellar type III export chaperones establish the assembly order of the filament at the hook tip. Here, we describe our current understanding of a hierarchical protein export mechanism used in flagellar type III protein export.

Sexual Hookup Culture: A Review

PubMed Central

Garcia, Justin R.; Reiber, Chris; Massey, Sean G.; Merriwether, Ann M.

2013-01-01

“Hookups,” or uncommitted sexual encounters, are becoming progressively more engrained in popular culture, reflecting both evolved sexual predilections and changing social and sexual scripts. Hook-up activities may include a wide range of sexual behaviors, such as kissing, oral sex, and penetrative intercourse. However, these encounters often transpire without any promise of, or desire for, a more traditional romantic relationship. A review of the literature suggests that these encounters are becoming increasingly normative among adolescents and young adults in North America, representing a marked shift in openness and acceptance of uncommitted sex. We reviewed the current literature on sexual hookups and considered the multiple forces influencing hookup culture, using examples from popular culture to place hooking up in context. We argue that contemporary hookup culture is best understood as the convergence of evolutionary and social forces during the developmental period of emerging adulthood. We suggest that researchers must consider both evolutionary mechanisms and social processes, and be considerate of the contemporary popular cultural climate in which hookups occur, in order to provide a comprehensive and synergistic biopsychosocial view of “casual sex” among emerging adults today. PMID:23559846

BOOK REVIEW: Robert Hooke and the Royal Society

NASA Astrophysics Data System (ADS)

Brown, Neil

2000-01-01

Many physics students only come across Hooke when they learn his law of stretching springs, which is a pity because it is just one of his contributions to progress in science, and a minor one at that. His, Micrographia, the first great book of microscopical observations, arouses admiration to this day. He was also active in horology, astronomy, geology and surveying, and he took part in biological experiments, transfusing blood between animals. Much of his work was done while he was curator of experiments for the Royal Society, in which he was involved almost from its foundation. This was by no means a full-time occupation, however. After the Great Fire of London, Hooke was appointed one of the three surveyors for the rebuilding of the city. One of the others was Christopher Wren, a lifelong friend. In this role Hooke was responsible for the design of several buildings, including the Monument. Nichols writes about all these activities, as well as Hooke's childhood, his education at Westminster School, the University of Oxford when Hooke was an undergraduate, and the founding of the Royal Society. The book draws on research for a master's degree. Turning a dissertation into a popular book is risky. The author has avoided the pitfall of making it too academic, but the result is not satisfying. Nichols seems overawed by Hooke and his work, frequently seeming to credit Hooke with a far-reaching influence that he did not necessarily have. There may be a case for lauding Hooke as the father of English microscopy, the father of English meteorology, and the founder of English geology and earth sciences, but it needs to be made much more critically, even in a popular work. Hooke was full of good ideas, but he rarely continued long enough to put them into practice. There is no doubt that Hooke proposed using a balance wheel and spring to improve the timekeeping of a watch, for example, but he did not have a watch made to his design until after Christiaan Huygens had independently devised a similar mechanism and published it. Hooke did propose a marine chronometer to solve the (already well understood) problem of finding longitude at sea, but it was John Harrison, decades later, who built a chronometer, and there is not the slightest reason to believe he owed anything to Hooke. The book records Hooke's activities, but is devoid of comment or analysis. The casual cruelty (by modern standards) to the animals used in the blood transfusion experiments passes without remark. The chapter about Oxford University reads almost like entries from a biographical dictionary. The purpose of this and the following chapter on the founding of the Royal Society only becomes apparent at the end, if the reader has not lost interest by then. Expert opinion acknowledges that the popular belief that Wren was primarily responsible for the rebuilding of the City of London undervalues Hooke's work, but Nichols, in his unwavering support for Hooke, glosses over the genuine problems of disentangling their contributions. The disputes between Hooke and Newton are well known, and no-one suggests that Newton was a pleasant person, but the unpleasantness was not all on one side. Historians agree that Hooke was a difficult man. There are no numbered references or notes, a not unusual policy in a popular book, but many sources (most of them secondary) are mentioned in the text. They do not help to make it read well, and the details are incomplete, but so are the details of many of the items listed in the bibliography. An index would be useful, but it is lacking. There are signs in a number of places that the book has not been carefully revised and edited. This ought to be a book to recommend to young students, but it would fail to inspire them. This is a pity, because there is no doubt that Hooke was one of the towering figures of the beginning of the scientific revolution. The fledgling Royal Society might not have survived without the experiments and demonstrations he provided. Historians know this but it deserves to be more widely recognized.

Measured oxygen fugacities of the Angra dos Reis achondrite as a function of temperature

USGS Publications Warehouse

Brett, R.; Stephen, Huebner J.; Sato, M.

1977-01-01

Measurements of the oxygen fugacity (f{hook}O2) as a function of temperature (T) were made on an interior bulk sample of the cumulate achondrite, Angra dos Reis. Data clustered between the f{hook}O2-T relationship of the iron-wu??stite assemblage and 1.2 log atm units above iron-wu??stite. Interpretation of the data indicates that, throughout most of the cooling history of the meteorite, f{hook}O2 values were defined by equilibria involving iron-bearing species at values close to the f{hook}O2 of the assemblage iron-wu??stite. Measured f{hook}O2 data are compatible with crystallization and cooling at pressures greater than 50 bars. ?? 1977.

Evaluation of the orientation of 90* and 180* reinforcing bar hooks.

DOT National Transportation Integrated Search

2012-01-01

This report describes test results of a study initiated to evaluate the potential influence of hook tilt angle of standard reinforcing hooks : on the bond strength of concrete. The topic of the evaluation of the orientation of 90 and 180 degree reinf...

Specific arrangement of alpha-helical coiled coils in the core domain of the bacterial flagellar hook for the universal joint function.

PubMed

Fujii, Takashi; Kato, Takayuki; Namba, Keiichi

2009-11-11

The bacterial flagellar hook is a short, highly curved tubular structure connecting the rotary motor to the filament acting as a helical propeller. The bending flexibility of the hook allows it to work as a universal joint. A partial atomic model of the hook revealed a sliding intersubunit domain interaction along the protofilament to produce bending flexibility. However, it remained unclear how the tightly packed inner core domains can still permit axial extension and compression. We report advances in cryoEM image analysis for high-resolution, high-throughput structural analysis and a density map of the hook that reveals most of the secondary structures, including the terminal alpha helices forming a coiled coil. The orientations and axial packing interactions of these two alpha helices are distinctly different from those of the filament, allowing them to have a room for axial compression and extension for bending flexibility without impairing the mechanical stability of the hook.

Structure of the bacterial flagellar hook and implication for the molecular universal joint mechanism.

PubMed

Samatey, Fadel A; Matsunami, Hideyuki; Imada, Katsumi; Nagashima, Shigehiro; Shaikh, Tanvir R; Thomas, Dennis R; Chen, James Z; Derosier, David J; Kitao, Akio; Namba, Keiichi

2004-10-28

The bacterial flagellum is a motile organelle, and the flagellar hook is a short, highly curved tubular structure that connects the flagellar motor to the long filament acting as a helical propeller. The hook is made of about 120 copies of a single protein, FlgE, and its function as a nano-sized universal joint is essential for dynamic and efficient bacterial motility and taxis. It transmits the motor torque to the helical propeller over a wide range of its orientation for swimming and tumbling. Here we report a partial atomic model of the hook obtained by X-ray crystallography of FlgE31, a major proteolytic fragment of FlgE lacking unfolded terminal regions, and by electron cryomicroscopy and three-dimensional helical image reconstruction of the hook. The model reveals the intricate molecular interactions and a plausible switching mechanism for the hook to be flexible in bending but rigid against twisting for its universal joint function.

Interdependence of the rad50 hook and globular domain functions.

PubMed

Hohl, Marcel; Kochańczyk, Tomasz; Tous, Cristina; Aguilera, Andrés; Krężel, Artur; Petrini, John H J

2015-02-05

Rad50 contains a conserved Zn(2+) coordination domain (the Rad50 hook) that functions as a homodimerization interface. Hook ablation phenocopies Rad50 deficiency in all respects. Here, we focused on rad50 mutations flanking the Zn(2+)-coordinating hook cysteines. These mutants impaired hook-mediated dimerization, but recombination between sister chromatids was largely unaffected. This may reflect that cohesin-mediated sister chromatid interactions are sufficient for double-strand break repair. However, Mre11 complex functions specified by the globular domain, including Tel1 (ATM) activation, nonhomologous end joining, and DNA double-strand break end resection were affected, suggesting that dimerization exerts a broad influence on Mre11 complex function. These phenotypes were suppressed by mutations within the coiled-coil and globular ATPase domains, suggesting a model in which conformational changes in the hook and globular domains are transmitted via the extended coils of Rad50. We propose that transmission of spatial information in this manner underlies the regulation of Mre11 complex functions. Copyright © 2015 Elsevier Inc. All rights reserved.

Revascularization of immature mandibular premolar with pulpal necrosis - a case report.

PubMed

Raju, S Murali Krishna; Yadav, Sarjeev Singh; Kumar M, Sita Rama

2014-09-01

This case report describes the Revascularization of a Permanent Immature Mandibular Premolar with Pulp Necrosis and apical periodontitis. Access opening was done & the canal was disinfected with copious irrigation using 2.5% NaOCl and triple antibiotic paste (Ciprofloxacin, Metronidazole, and Minocycline) as intracanal medicament. After the disinfection protocol is complete, it is followed by revascularization procedure. The apex was mechanically irritated to initiate bleeding into the canal to produce a blood clot to the level just below the level of cementoenamel junction. Mineral trioxide aggregate was placed over the blood clot followed by bonded resin restoration above it. After one year follow up; the patient was asymptomatic, no sinus tract was evident. Apical periodontitis was resolved, and there was radiographic evidence of continuing thickness of dentinal walls.

[ZHENG's gold hook fishing acupuncture for lumbar disc herniation: a clinical observation].

PubMed

Zhu, Bowen; Zhang, Xinghua; Sun, Runjie; Qin, Xiaoguang

2016-04-01

To compare the clinical efficacy differences between Zheng's gold hook, fishing acupuncture and electroacupuncture (EA) for lumbar disc herniation (LDH). Sixty patients of LDH were randomly allocated to a gold hook fishing acupuncture group and an EA group, 30 cases in each one. Lumbar Jiaji (EX-1 B 2), Yaoyangguan (GV 3), Shenshu (BL 23), Dachangshu (BL 25), Guanyuanshu (BL 26) and ashi points were selected in the gold hook fishing acupuncture group; after the needles were inserted, the manipulation of gold hook fishing acupuncture was applied at tendon junction points and ashi points. The identical acupoints were selected in the EA group and patients were treated with EA. The treatment was both given once a day; ten days of treatment were taken as one session, and totally 3 sessions were given. The clinical effective rate, visual analogue scale (VAS), low back pain score and Oswestry disability index (ODI) were used for efficacy evaluation. The effective rate was 93.3% (28/30) in the gold hook fishing acupuncture group, which was superior to 86.7% (26/30) in the EA group (P < 0.05). The VAS, low back pain score and ODI were both significantly improved after treatment (all P < 0.05), which were more significant in the gold hook fishing acupuncture group (all P < 0.05). ZHENG's gold hook fishing acupuncture could effectively improve the symptoms and sings of LDH, reduce the disability index and improve the quality of life, which is superior to EA.

Laparoscopic heller myotomy for achalasia cardia-initial experience in a teaching institute.

PubMed

Kaman, Lileswar; Iqbal, Javid; Kochhar, Rakesh; Sinha, Saroj

2013-10-01

Laparoscopic Heller cardiomyotomy and Dor fundoplication is the surgical procedure of choice for esophageal achalasia. The aim of our study was to investigate the clinical outcome and safety of laparoscopic Heller-Dor procedure performed by using Hook electrocautery and as a teaching module for advanced laparoscopic surgery. Between January 2005 and December 2010, 25 consecutive patients with achalasia underwent laparoscopic Heller-Dor operation by a single surgeon. All the patients received upper gastrointestinal series (barium swallow), esophagogastroscopy, and esophageal manometry to exclude esophageal carcinoma and to confirm the diagnosis. All the patients were operated by laparoscopic modified Heller myotomy with Dor fundoplication by using hook electrocautery. Among 25 operated patients, 14 were male and 11 were female with a median age of 43 years (range 18-72 years). The mean operative time was 93.3 min (range 50-50 min), the mean operative blood loss was 90 ml (range 40-200 ml), the median time to oral feeding was 2 days (2-4 days), and the median hospital stay was 4 days (4-7 days). There was no conversion to open surgery. Intraoperative mucosal perforation was encountered in three patients and was repaired in all of them by laparoscopic suture. All the patients had an uneventful recovery without postoperative complication and had excellent clinical response (96 %) during follow-up. Laparoscopic Heller-Dor operation using hook electrocautery is safe, inexpensive, and effective treatment for achalasia which is useful for teaching and training surgical residents in advanced laparoscopic surgery.

Numerical stress analysis of the iris tissue induced by pupil expansion: Comparison of commercial devices

PubMed Central

Wang, Xiaofei; Perera, Shamira A.; Girard, Michaël J. A.

2018-01-01

Purpose (1) To use finite element (FE) modelling to estimate local iris stresses (i.e. internal forces) as a result of mechanical pupil expansion; and to (2) compare such stresses as generated from several commercially available expanders (Iris hooks, APX dilator and Malyugin ring) to determine which design and deployment method are most likely to cause iris damage. Methods We used a biofidelic 3-part iris FE model that consisted of the stroma, sphincter and dilator muscles. Our FE model simulated expansion of the pupil from 3 mm to a maximum of 6 mm using the aforementioned pupil expanders, with uniform circular expansion used for baseline comparison. FE-derived stresses, resultant forces and area of final pupil opening were compared across devices for analysis. Results Our FE models demonstrated that the APX dilator generated the highest stresses on the sphincter muscles, (max: 6.446 MPa; average: 5.112 MPa), followed by the iris hooks (max: 5.680 MPa; average: 5.219 MPa), and the Malyugin ring (max: 2.144 MPa; average: 1.575 MPa). Uniform expansion generated the lowest stresses (max: 0.435MPa; average: 0.377 MPa). For pupil expansion, the APX dilator required the highest force (41.22 mN), followed by iris hooks (40.82 mN) and the Malyugin ring (18.56 mN). Conclusion Our study predicted that current pupil expanders exert significantly higher amount of stresses and forces than required during pupil expansion. Our work may serve as a guide for the development and design of next-generation pupil expanders. PMID:29538452

Unusual extraction treatment in Class II division 1 using C-orthodontic mini-implants.

PubMed

Chung, Kyu-Rhim; Cho, Jae-Hee; Kim, Seong-Hun; Kook, Yoon-Ah; Cozzani, Mauro

2007-01-01

This paper describes the treatment of a female patient, aged 23 years and 5 months, with a Class II division 1 malocclusion, who showed severe anterior protrusion and lower anterior crowding. Specially-designed orthodontic mini-implants were placed bilaterally in the interdental space between both the upper and the lower posterior teeth. Both lower first molars showed severe apical lesions. Therefore, the treatment plan consisted of extraction of both upper first premolars and lower first molars, en masse retraction of the upper six anterior teeth, lower anterior alignment, and protraction of all the lower molars. C-implants(R) were used as substitutes for maxillary posterior anchorage teeth during anterior retraction and as hooks for mandibular molar protraction. The correct overbite and overjet were obtained by intruding and retracting the upper six anterior teeth into their proper positions. The dentition was detailed using conventional orthodontic appliances. The upper C-implants contributed to an improvement in facial balance, and the lower C-implants made it possible to protract the lower second and third molars with less effect on the axis of the lower anterior teeth. The active treatment period was 29 months and the patient's teeth continued to be stable 11 months after debonding.

Ultrastructural aspects of the oesophageal and reproductive systems of the equine parasite Strongylus vulgaris.

PubMed

Mobarak, M S; Ryan, M F

2002-06-01

The ultrastructure of the dorsal oesophageal gland ampulla and its relationship with the oesophagus, oesophageal ultrastructure, and control mechanisms in oesophageal activity were studied. Terminal ducts of the sub-ventral glands open through the oesophageal crown at the base of the buccal cavity. The terminal duct of the dorsal oesophageal gland running through the dorsal gutter opens to the exterior at the rim 'groove' of the buccal capsule. The posterior oesophageal region is clavate and the cuticle of the lumen folds to form outlet valves, 'valvulae'. An inconspicuous oesophago-intestinal valve (three lobes) connects oesophagus and intestine and is visualized in the open and shut position. In the female reproductive tract, with the exception of the uterus, the cells lie on a thick, irregular (convoluted) basal lamina. The apical plasma membrane of the uterus, and seminal receptacle, extend into the lumen by microvilli-like projections with which spermatozoa make intimate contact. The lumen of the uterus is filled with oocytes, fertilized and unfertilized. Testicular cells have two parts linked by a rachis. Spermatocytes are elongated with a large nucleus, distinct nuclear membrane, and many granules. The apical membrane of the rachis forms long microvilli-like projections with balloon-like tips. The amoeboid spermatozoa contain membrane specializations, a nucleus devoid of a membrane, and are enclosed by a pseudopodial-like extension.

Attachment reaction of rat uterine luminal epithelium. II. The effect of progesterone on the morphology of the uterine glands and the luminal epithelium of the spayed, virgin rat.

PubMed

Ljungkvist, I

1971-01-01

Ovariosalpingectomized rat uterine glands and luminal epithelium were examined by electron microscopy and in serial cross sections under light microscopy after up to 8 days of treatment with 5 mg progesterone daily. Under light microscopy, the gland lumen was narrow or absent in many epon sections, but wide in many paraffin sections, filled with toluidine blue stained secretion, and serial sections showed that the openings were closed, allowing no connection between the gland lumen and the uterus. In electron micrographs, only those glands without an opening appeared altered by progesterone. The most notable differences in the glandular epithelium were microvilli, condensed ribosome-free cytoplasm next to the lumen, numerous vesicles, sacs and dilated Golgi cisternae in the apical cytoplasm, and more giant mitrochondria in the basal cytoplasm than usually seen in controls. In the luminal epithelium, there were 3 distinct regions: the apical region had condensed cytoplasm often extruded into the lumen, with close-packed, smooth, empty vesicles; the middle region had granular endoplasmic reticulum, mitrochondria, dense bodies, multivesicular bodies, and lipid granules; the basal region contained the nucleus, granular endoplasmic reticulum, mitrochondria and dense abodies. These observations were interpreted as indicative of a transitional state from secretion to absorption, especially since without an opening, secretion would be of little significance.

77 FR 15722 - Southern California Hook and Line Survey; Public Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-16

... meeting to evaluate the Southern California Shelf Rockfish Hook and Line Survey which was designed to... and Line survey design and protocols; (2) examine the analytical methods used to generate rockfish... California Hook and Line Survey; Public Meeting AGENCY: National Marine Fisheries Service (NMFS), National...

29 CFR 1926.1431 - Hoisting personnel.

Code of Federal Regulations, 2011 CFR

2011-07-01

... hook, load line and rigging) must not exceed 50 percent of the rated capacity for the radius and... pursuant to paragraph (b)(2) of this section, the total load (including the hook, load line, rigging and... number required to perform the work, whichever is less. (g) Attachment and rigging. (1) Hooks and other...

29 CFR 1926.1431 - Hoisting personnel.

Code of Federal Regulations, 2014 CFR

2014-07-01

... hook, load line and rigging) must not exceed 50 percent of the rated capacity for the radius and... pursuant to paragraph (b)(2) of this section, the total load (including the hook, load line, rigging and... number required to perform the work, whichever is less. (g) Attachment and rigging—(1) Hooks and other...

Are College Students Replacing Dating and Romantic Relationships with Hooking Up?

ERIC Educational Resources Information Center

Siebenbruner, Jessica

2013-01-01

This study assessed female college students' ("N" = 197) participation in dating, romantic relationships, hooking up behaviors, and the intersection of these activities. Hooking up was prevalent among students ("n" = 78; 39.6%), but dating ("n" = 139; 70.6%) and romantic relationship ("n" = 147; 74.6%)…

In vitro Antioxidant of a Water-Soluble Polysaccharide from Dendrobium fimhriatum Hook.var.oculatum Hook

PubMed Central

Luo, Aoxue; Fan, Yijun

2011-01-01

A water-soluble crude polysaccharide (DFHP) obtained from the aqueous extracts of the stem of Dendrobium fimhriatum Hook.var.oculatum Hook through hot water extraction followed by ethanol precipitation, was found to have an average molecular weight (Mw) of about 209.3 kDa. Monosaccharide analysis revealed that DFHP was composed of mannose, glucose and galactose in a content ratio of 37.52%; 43.16%; 19.32%. The investigation of antioxidant activity in vitro showed that DFHP is a potential antioxidant. PMID:21747725

Relationship between tornadoes and hook echoes on April 3, 1974

NASA Technical Reports Server (NTRS)

Forbes, G. S.

1975-01-01

Radar observations of tornado families occurring on April 3, 1974 are discussed. Of the 93 tornadoes included in the sample, 81% were associated with hook-like echoes with appendages at least 40 deg to the south of the echo movement. At least one tornado was associated with 62% of the hook-like echoes observed. All of the tornadoes with intensities of F 4 and F 5 were produced by hook-like echoes; the mean intensity of all tornadoes associated with this type of echo was F 3, while the mean intensity of the remaining tornadoes was F1. The tornadic hook-like echoes moved to the right of the non-tornadic echoes forming a tornado line in advance of the squall line. Some tornadoes were associated with 'spiral' echoes.

Identification of Aroma-active Compounds in Essential Oil from Uncaria Hook by Gas Chromatography- Mass Spectrometry and Gas Chromatography-Olfactometry.

PubMed

Iwasa, Megumi; Nakaya, Satoshi; Maki, Yusuke; Marumoto, Shinsuke; Usami, Atsushi; Miyazawa, Mitsuo

2015-01-01

The chemical composition of essential oil extracted from Uncaria Hook ("Chotoko" in Japanese), the branch with curved hook of the herbal medicine Uncaria rhynchophylla has been investigated by GC and GC-MS analyses. Eighty-four compounds, representing 90.8% of the total content was identified in oil obtained from Uncaria Hook. The main components i were (E)-cinnamaldehyde (13.4%), α-copaene (8.0%), methyl eugenol (6.8%), δ-cadinene (5.3%), and curcumene (3.6%). The important key aroma-active compounds in the oil were detected by gas chromatography-olfactometry (GC-O) and aroma extract dilution analysis (AEDA), using the flavor dilution (FD) factor to express the odor potency of each compounds. Furthermore, the odor activity value (OAV) has been used as a measure of the relative contribution of each compound to the aroma of the Uncaria Hook oil. The GC-O and AEDA results showed that α-copaene (FD = 4, OAV = 4376), (E)-linalool oxide (FD = 64, OAV = 9.1), and methyl eugenol (FD = 64, OAV = 29) contributed to the woody and spicy odor of Uncaria Hook oil, whereas furfural (FD = 8, OAV = 4808) contributed to its sweet odor. These results warrant further investigations of the application of essential oil from Uncaria Hook in the phytochemical and medicinal fields.

Engineering Evaluation of International Low Impact Docking System Latch Hooks

NASA Technical Reports Server (NTRS)

Martinez, J.; Patin, R.; Figert, J.

2013-01-01

The international Low Impact Docking System (iLIDS) provides a structural arrangement that allows for visiting vehicles to dock with the International Space Station (ISS) (Fig 1). The iLIDS docking units are mechanically joined together by a series of active and passive latch hooks. In order to preserve docking capability at the existing Russian docking interfaces, the iLIDS latch hooks are required to conform to the existing Russian design. The latch hooks are classified as being fail-safe. Since the latch hooks are fail-safe, the hooks are not fracture critical and a fatigue based service life assessment will satisfy the structural integrity requirements. Constant amplitude fatigue testing to failure on four sets of active/passive iLIDS latch hooks was performed at load magnitudes of 10, 11, and 12 kips. Failure analysis of the hook fatigue failures identified multi-site fatigue initiation that was effectively centered about the hook mid-plane (consistent with the 3D model results). The fatigue crack initiation distribution implies that the fatigue damage accumulation effectively results in a very low aspect ratio surface crack (which can be simulated as thru-thickness crack). Fatigue damage progression resulted in numerous close proximity fatigue crack initiation sites. It was not possible to determine if fatigue crack coalescence occurs during cyclic loading or as result of the fast fracture response. The presence of multiple fatigue crack initiation sites on different planes will result in the formation of ratchet marks as the cracks coalesce. Once the stable fatigue crack becomes unstable and the fast fracture advances across the remaining ligament and the plane stress condition at a free-surface will result in failure along a 45 deg. shear plane (slant fracture) and the resulting inclined edge is called a shear lip. The hook thickness on the plane of fatigue crack initiation is 0.787". The distance between the shear lips on this plane was on the order of 0.48" and it was effectively centered about the mid-plane of the section. The numerous ratchet marks between the shear lips on the fracture initiation plane are indicative of multiple fatigue initiation sites within this region. The distribution of the fatigue damage about the centerline of the hook is consistent with the analytical results that demonstrate peak stress/strain response at the mid-plane that decreases in the direction of the hook outer surfaces. Scanning electron microscope images of the failed sections detected fatigue crack striations in close proximity to the free surface of the hook radius. These findings were documented at three locations on the fracture surface : 1) adjacent to the left shear lip, 2) adjacent to the right shear lip, and 3) near the centerline of the section. The features of the titanium fracture surface did not allow for a determination of a critical crack size via identification of the region where the fatigue crack propagation became unstable. The fracture based service life projections where benchmarked with strain-life analyses. The strainrange response in the hook radius was defined via the correlated finite element models and the modified method of universal slopes was incorporated to define the strain-life equation for the titanium alloy. The strain-life assessment confirmed that the fracture based projections were reasonable for the loading range of interest. Based upon the analysis and component level fatigue test data a preliminary service life capability for the iLIDS active and passive hooks of 2 lifetimes is projected (includes a scatter factor of 4).

Citizen science data suggest that a novel rig improves landing rate and reduces injury and handling time in recreational angling with artificial lures in Baltic pike (Esox lucius).

PubMed

Bursell, Jens Jakob; Arlinghaus, Robert

2018-01-01

The optimal terminal gear in hook-and-line recreational fishing maximizes landing rates and minimizes injury to the fish because some fish will be released after capture. We designed a novel rig configuration in artificial lure fishing for top predators and examined its effectiveness in angling for Baltic northern pike ( Esox lucius ) using a citizen science approach based on observational data collected from volunteer anglers in the field. The novel rig included two changes to traditional rig designs common to artificial lure angling. First, hooks were mounted in a way giving better hook exposure and eliminating lever-arm effects from the lure to the hooks once a fish is hooked. This construction allowed the second change, being a shift to hooks 4-5 sizes smaller than those used on traditional hook mounts. We analysed observational data collected by volunteer anglers using either the novel rig or a standard rig mount in two types of artificial lures (softbait and hardbait) of the same size (about 17 cm). Using N  = 768 pike contacts as input data, we showed the landing rates of pike targeted with artificial lures significantly and substantially increased from 45% with normal-rigs to 85% when the same lure types were fished with the novel rig configuration. Lure type and water temperature had no effects on landing rates. Moreover, hardbaits on normal-rigs produced significantly more injury, bleeding and elevated unhooking time compared to fish captured on hardbaits with release-rigs. We conclude that simple changes to traditional hook sizes and mounts in lure fishing may benefit both anglers and the fishes that are to be released and that citizen science projects with volunteer anglers are able to provide good data in proof-of-concept studies. Further experimental studies are needed to differentiate hook size from hook mount effects because both variables were confounded in the results of the observational data presented here.

Single-channel analysis of functional epithelial sodium channel (ENaC) stability at the apical membrane of A6 distal kidney cells

PubMed Central

Yu, Ling; Helms, My N.; Yue, Qiang; Eaton, Douglas C.

2008-01-01

Epithelial sodium channels (ENaC) play an essential role in maintaining total body fluid and electrolyte homeostasis. As such, abnormal expression of ENaC at the cell surface is linked to several important human diseases. Although the stability of ENaC subunits has been extensively studied by protein biochemical analysis, the half-life of the functional channel in the apical membrane remains controversial. Because the functional stability of the multisubunit channel may be more physiologically relevant than the stability of individual subunit proteins, we performed studies of functional ENaC channels using A6 epithelial cells, a Xenopus laevis distal nephron cell line. We recorded single-channel activity in over 400 cells with the translation blockers cycloheximide (CHX) or puromycin, as well as the intracellular protein trafficking inhibitors brefeldin A (BFA) or nocodazole. Our cell-attached, single-channel recordings allow us to quantify the channel density in the apical membrane, as well as to determine channel open probability (Po) from control (untreated) cells and from cells at different times of drug treatment. The data suggest that the half-life of ENaC channels is ∼3.5 h following puromycin, BFA, and nocodazole treatment. Furthermore, these three drugs had no significant effect on the Po of ENaC for at least 6 h after exposure. A decrease in apical channel number and Po was observed following 2 h of CHX inhibition of protein synthesis, and the apparent channel half-life was closer to 1.5 h following CHX treatment. Treatment of cells with the translation inhibitors does not alter the expression of the protease furin, and therefore changes in protease activity cannot explain changes in ENaC Po. Confocal images show that BFA and nocodazole both disrupt most of the Golgi apparatus after 1-h exposure. In cells with the Golgi totally disrupted by overnight exposure to BFA, 20% of apical ENaC channels remained functional. This result suggests that ENaC is delivered to the apical membrane via a pathway that might bypass the Golgi vesicular trafficking pathway, or that there might be two pools of channels with markedly different half-lives in the apical membrane. PMID:18784262

Single-channel analysis of functional epithelial sodium channel (ENaC) stability at the apical membrane of A6 distal kidney cells.

PubMed

Yu, Ling; Helms, My N; Yue, Qiang; Eaton, Douglas C

2008-11-01

Epithelial sodium channels (ENaC) play an essential role in maintaining total body fluid and electrolyte homeostasis. As such, abnormal expression of ENaC at the cell surface is linked to several important human diseases. Although the stability of ENaC subunits has been extensively studied by protein biochemical analysis, the half-life of the functional channel in the apical membrane remains controversial. Because the functional stability of the multisubunit channel may be more physiologically relevant than the stability of individual subunit proteins, we performed studies of functional ENaC channels using A6 epithelial cells, a Xenopus laevis distal nephron cell line. We recorded single-channel activity in over 400 cells with the translation blockers cycloheximide (CHX) or puromycin, as well as the intracellular protein trafficking inhibitors brefeldin A (BFA) or nocodazole. Our cell-attached, single-channel recordings allow us to quantify the channel density in the apical membrane, as well as to determine channel open probability (Po) from control (untreated) cells and from cells at different times of drug treatment. The data suggest that the half-life of ENaC channels is approximately 3.5 h following puromycin, BFA, and nocodazole treatment. Furthermore, these three drugs had no significant effect on the Po of ENaC for at least 6 h after exposure. A decrease in apical channel number and Po was observed following 2 h of CHX inhibition of protein synthesis, and the apparent channel half-life was closer to 1.5 h following CHX treatment. Treatment of cells with the translation inhibitors does not alter the expression of the protease furin, and therefore changes in protease activity cannot explain changes in ENaC Po. Confocal images show that BFA and nocodazole both disrupt most of the Golgi apparatus after 1-h exposure. In cells with the Golgi totally disrupted by overnight exposure to BFA, 20% of apical ENaC channels remained functional. This result suggests that ENaC is delivered to the apical membrane via a pathway that might bypass the Golgi vesicular trafficking pathway, or that there might be two pools of channels with markedly different half-lives in the apical membrane.

Molecular Signaling Involved in Entry and Exit of Malaria Parasites from Host Erythrocytes.

PubMed

Singh, Shailja; Chitnis, Chetan E

2017-10-03

During the blood stage, Plasmodium spp. merozoites invade host red blood cells (RBCs), multiply, exit, and reinvade uninfected RBCs in a continuing cycle that is responsible for all the clinical symptoms associated with malaria. Entry into (invasion) and exit from (egress) RBCs are highly regulated processes that are mediated by an array of parasite proteins with specific functional roles. Many of these parasite proteins are stored in specialized apical secretory vesicles, and their timely release is critical for successful invasion and egress. For example, the discharge of parasite protein ligands to the apical surface of merozoites is required for interaction with host receptors to mediate invasion, and the timely discharge of proteases and pore-forming proteins helps in permeabilization and dismantling of limiting membranes during egress. This review focuses on our understanding of the signaling mechanisms that regulate apical organelle secretion during host cell invasion and egress by malaria parasites. The review also explores how understanding key signaling mechanisms in the parasite can open opportunities to develop novel strategies to target Plasmodium parasites and eliminate malaria. Copyright © 2017 Cold Spring Harbor Laboratory Press; all rights reserved.

Bone microstrain values of 1-piece and 2-piece implants subjected to mechanical loading.

PubMed

Harel, Noga; Eshkol-Yogev, Inbar; Piek, Dana; Livne, Shiri; Lavi, David; Ormianer, Zeev

2013-06-01

The purpose of this study was to measure and compare the strain levels in peri-implant bone as generated by 1-piece (1P) and 2-piece (2P) implant systems. The implants (1P and 2P) were placed into bovine bone according to the manufacturer's protocol. Four linear strain gauges were placed around each implant neck and apex. Each model was loaded in static loading by a material testing machine in ascending forces ranging from 20 to 120 N. Microstrains (μ[Latin Small Letter Open E]) generated in the surrounding bone were measured by a strain gauge and recorded. Recorded microstrains were significantly higher for 1P implants than for 2P implants. Average recorded microstrain values were significantly lower in the neck (71.6 and 17.3 µs) compared with the apical (132 and 60 µs) regions of 1P and 2P implants, respectively (P < 0.0001). Within the limitations of this study, highest microstrains were generated in apical regions regardless of implant design, but the 2P implant ap-peared to provide a stress-damping effect in both the cervical and apical regions compared with the 1P implant.

When Teachers Aren't Nice: bell hooks and Feminist Pedagogy.

ERIC Educational Resources Information Center

Buffington, Nancy

The recent "feminization" of composition theory and pedagogy has replaced the classroom figure of the authoritative father with an image of a nurturing mother. But as bell hooks and others insist, the classroom is inherently a place of struggle and conflict and the "real world" is even more so. Hooks offers concrete…

50 CFR 665.812 - Sea turtle take mitigation measures.

Code of Federal Regulations, 2010 CFR

2010-10-01

....812 Section 665.812 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND... of hook sizes and styles used by the vessel. (B) Extended reach handle. The hook removal device must... hook sizes and styles used by the vessel. (B) Handle. The handle must have a length equal to or greater...

33 CFR 80.170 - Sandy Hook, NJ to Tom's River, NJ.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Sandy Hook, NJ to Tom's River, NJ. 80.170 Section 80.170 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Atlantic Coast § 80.170 Sandy Hook, NJ to Tom's River...

Collaborative Lesson Hook Design in Science Teacher Education: Advancing Professional Practice

ERIC Educational Resources Information Center

McCauley, Veronica; Davison, Kevin; Byrne, Corinna

2015-01-01

This article documents the process of collaboratively developing lesson hook e-resources for science teachers to establish a community of inquiry and to strengthen the pedagogy of science teaching. The authors aim to illustrate how the development and application of strategic hooks can bridge situational interest and personal interest so that…

Getting Hooked on Physics!

NASA Astrophysics Data System (ADS)

McHugh, M.; McCauley, V.

2016-12-01

A number of papers in this journal have dealt with the idea of using hooks in physics instruction. A hook, as the name suggests, engages students in learning by triggering their attention and interest. Hooks can be any type of pedagogical approach—a question, a demonstration, a puzzle or video. They are generally short and center on the most interesting aspects of a topic. Here we focus on using Conceptual Change (CC) teacher-led demonstrations as the pedagogical hook approach. Conceptual Change is an instructional method mentioned by a number of authors to stimulate interest among learners. This is where an educator presents an issue or topic that has associated misconceptions. As the teacher explains the truth behind the concept, cognitive conflict occurs and the students' initial perceptions are challenged and ideas start to change. However, the instruction used in association with the demonstrations must provide intelligible, plausible, relevant explanations so that students are convinced by the new ideas. The gap between prior knowledge and new knowledge has the potential to provide a strong stimulus for augmenting interest, engagement, and attention among students. Thus, CC can act as a hook in itself.

High-dose hook effect in six automated human chorionic gonadotrophin assays.

PubMed

Al-Mahdili, Huda A; Jones, Graham R D

2010-07-01

The high-dose hook effect is a well-known phenomenon of two-site immunoassays including those for human chorionic gonadotrophin (hCG). We investigated the occurrence of a high-dose hook effect in six routinely available hCG assays using a sample with a total hCG concentration of approximately 3,600,000 IU/L. Dilutions of a sample with high hCG concentration were analysed using six common methods: Advia Centaur, Immulite 2000, Dimension RxL, Unicel DxI 800, Roche E170 and Abbott Architect. The measured concentrations and corresponding assay signals were obtained for each method. Performance was compared with manufacturer claims. Four of the tested platforms demonstrated a clear high-dose hook effect, while the other methods showed no hook effect at the highest level tested. Our results indicate that the hook effect may occur in some hCG assays, although the risk of reporting falsely low results was in most cases at higher concentrations than those indicated in manufacturers' product information. Assay design plays a major role in its occurrence. Laboratories should be aware of the assay limitations in this regard.

Fish-hook injuries: a risk for fishermen

PubMed Central

2010-01-01

Fishing is one of the best known and practiced human activities. However, you should remember that, when casting the hook from the riverbank or grasping it to add bait, fishermen run a real risk of injury if the hook punctures the skin. Briefly we describe a case where a young, 32-year-old fisherman who was reeling the hook back to shore when it hit him in the face and embedded itself in his upper eyelid. Upon examination, the eye was found to be unharmed and the hook was removed through a small incision and the aid of a local anesthetic. In the light of this case report, we think it a good idea to advise our friends and patients who we know to be fishermen to wear some form of eye protection as a precaution. PMID:21156039

Talk about "hooking up": the influence of college student social networks on nonrelationship sex.

PubMed

Holman, Amanda; Sillars, Alan

2012-01-01

This research considers how communication within college student social networks may encourage high-risk sexual relationships. Students (n = 274) described sexual scripts for hooking up and reported on peer communication, sexual behavior, and sexual attitudes. Students described varied hookup scripts, expressed ambivalent attitudes, and reported moderate participation in hookups overall. However, the most common hookup script, suggesting high-risk sexual activity (i.e., unplanned, inebriated sex), was featured in most accounts of students who themselves participated in hookups. Students overestimated how often others were hooking up, and these estimates were especially inflated by students who frequently talked about hooking up with friends. Among students with strong ties to peers, frequent peer communication about sex predicted participation in hookups and favorable attitudes about hooking up. Peer approval also predicted hookup behavior and attitudes.

False Negative Urine Pregnancy Testing with Complete Molar Pregnancy: An Example of the Hook Effect.

PubMed

Anderson, Zachary; Larson, Eric; Khan, Muhammad; Bell, Maria

2016-02-01

Gestational trophoblastic disease (GTD) encompasses a group of tumors derived from trophoblasts, which normally form the placenta during pregnancy. Human chorionic gonadotropin (hCG) is a glycoprotein composed of an alpha subunit identical to that of thyroid stimulating hormone (TSH), follicle-stimulating hormone (FSH), and luteinizing hormone (LH). Detection of beta-hCG is achievable in both urine and serum samples, proving useful for the detection of normal pregnancy and GTD. However, in the presence of very high levels of beta-hCG, a false negative result may be obtained due to a phenomenon called the "hook effect" or "prozone phenomenon." In certain circumstances, trophoblastic tumors can produce very high levels of beta-hCG, causing misleading results on urine pregnancy testing. A 49-year-old Caucasian female with past medical history pertinent for deep vein thrombosis, ovarian cysts, and osteopenia presented to her internist with report of irregular uterine bleeding for the preceding three months, accompanied by complaints of abdominal bloating, night sweats, and constipation. The patient stated she had completed two negative qualitative urine pregnancy tests and had been seen by both gynecology and gastroenterology, with recommendations to start supplemental estrogen for her symptoms and begin additional fiber intake for irritable bowel syndrome, respectively. Despite negative urine beta-hCG, a quantitative serum beta-hCG was obtained and revealed a level greater than 200,000 international units (IU). The patient was referred to gynecologic oncology and an open abdominal hysterectomy with preservation of her ovaries was performed. Histopathologic examination showed a complete hydatiform mole with no evidence of invasion. The case highlights the importance of clinical judgment in modern medicine, where biochemical methods and imaging modalities have become main stays in diagnosis. As mentioned, there are ways to reduce the incidence of the hook effect, but with added time and cost. Clinicians need to consider the possibility of the hook effect for instances where the clinical picture points to a disease entity despite negative test results. Delaying diagnoses, as illustrated with GTD, has the potential to cause significant morbidity and mortality.

Small synthetic peptides homologous to segments of the first external loop of occludin impair tight junction resealing.

PubMed

Lacaz-Vieira, F; Jaeger, M M; Farshori, P; Kachar, B

1999-04-01

This study shows that resealing of opened tight junctions (TJs) is impaired by interaction with oligopeptides homologous to the external domain of chick occludin. The experiments were carried out with confluent A6 cell monolayers grown on collagen supports under stable transepithelial electrical resistance (TER). The monolayers were bathed on the apical side with a 75 mm KCl solution and on the basolateral side by NaCl-Ringer's solution. TJ opening was induced by basolateral Ca2+ removal and was characterized by a marked drop of TER. The reintroduction of Ca2+ triggered junction resealing as indicated by an elevation of TER to control values. Custom-made peptides SNYYGSGLSY (corresponding to the residues 100 to 109) and SNYYGSGLS (residues 100 to 108), homologous to segments of the first external loop of chick occludin molecule, impaired junction resealing when the peptides were included in the apical bathing fluid (concentrations in the range of 0.5 to 1.5 mg/ml). Peptide removal from the apical solution usually triggered a slow recovery of TER, indicating a slow recovery of the TJ seal. Changes in localization of ZO-1, a cytoplasmic protein that underlies the membrane at the TJs, were evaluated immunocytochemically following Ca2+ removal and reintroduction. The presence or absence of the oligopeptides showed no influence on the pattern of change of ZO-1 localization. These observations support the hypothesis that the TJ seal results from the interaction of specific homologous segments of occludin on the surface of adjacent cells. Additionally, our results show that small peptides homologous to segments of the occludin first external loop can be used as specific reagents to manipulate the permeability of tight junctions.

Greenland shark (Somniosus microcephalus) feeding behavior on static fishing gear, effect of SMART (Selective Magnetic and Repellent-Treated) hook deterrent technology, and factors influencing entanglement in bottom longlines

PubMed Central

Sullivan, Rennie; Hedges, Kevin J.

2018-01-01

The Greenland Shark (Somniosus microcephalus) is the most common bycatch in the Greenland halibut (Reinhardtius hippoglossoides) bottom longline fishery in Cumberland Sound, Canada. Historically, this inshore fishery has been prosecuted through the ice during winter but winter storms and unpredictable landfast ice conditions since the mid-1990s have led to interest in developing a summer fishery during the ice-free season. However, bycatch of Greenland shark was found to increase substantially with 570 sharks captured during an experimental Greenland halibut summer fishery (i.e., mean of 6.3 sharks per 1,000 hooks set) and mortality was reported to be about 50% due in part to fishers killing sharks that were severely entangled in longline gear. This study investigated whether the SMART (Selective Magnetic and Repellent-Treated) hook technology is a practical deterrent to Greenland shark predation and subsequent bycatch on bottom longlines. Greenland shark feeding behavior, feeding kinematics, and variables affecting entanglement/disentanglement and release are also described. The SMART hook failed to deter Greenland shark predation, i.e., all sharks were captured on SMART hooks, some with more than one SMART hook in their jaw. Moreover, recently captured Greenland sharks did not exhibit a behavioral response to SMART hooks. In situ observations of Greenland shark feeding show that this species uses a powerful inertial suction mode of feeding and was able to draw bait into the mouth from a distance of 25–35 cm. This method of feeding is suggested to negate the potential deterrent effects of electropositive metal and magnetic alloy substitutions to the SMART hook technology. The number of hooks entangled by a Greenland shark and time to disentangle and live-release a shark was found to increase with body length. PMID:29785345

Greenland shark (Somniosus microcephalus) feeding behavior on static fishing gear, effect of SMART (Selective Magnetic and Repellent-Treated) hook deterrent technology, and factors influencing entanglement in bottom longlines.

PubMed

Grant, Scott M; Sullivan, Rennie; Hedges, Kevin J

2018-01-01

The Greenland Shark ( Somniosus microcephalus ) is the most common bycatch in the Greenland halibut ( Reinhardtius hippoglossoides ) bottom longline fishery in Cumberland Sound, Canada. Historically, this inshore fishery has been prosecuted through the ice during winter but winter storms and unpredictable landfast ice conditions since the mid-1990s have led to interest in developing a summer fishery during the ice-free season. However, bycatch of Greenland shark was found to increase substantially with 570 sharks captured during an experimental Greenland halibut summer fishery (i.e., mean of 6.3 sharks per 1,000 hooks set) and mortality was reported to be about 50% due in part to fishers killing sharks that were severely entangled in longline gear. This study investigated whether the SMART (Selective Magnetic and Repellent-Treated) hook technology is a practical deterrent to Greenland shark predation and subsequent bycatch on bottom longlines. Greenland shark feeding behavior, feeding kinematics, and variables affecting entanglement/disentanglement and release are also described. The SMART hook failed to deter Greenland shark predation, i.e., all sharks were captured on SMART hooks, some with more than one SMART hook in their jaw. Moreover, recently captured Greenland sharks did not exhibit a behavioral response to SMART hooks. In situ observations of Greenland shark feeding show that this species uses a powerful inertial suction mode of feeding and was able to draw bait into the mouth from a distance of 25-35 cm. This method of feeding is suggested to negate the potential deterrent effects of electropositive metal and magnetic alloy substitutions to the SMART hook technology. The number of hooks entangled by a Greenland shark and time to disentangle and live-release a shark was found to increase with body length.

Pre-operative localization of solitary pulmonary nodules with computed tomography-guided hook wire: report of 181 patients.

PubMed

Hanauer, Matthieu; Perentes, Jean Yannis; Krueger, Thorsten; Ris, Hans-Beat; Bize, Pierre; Schmidt, Sabine; Gonzalez, Michel

2016-01-16

Video-assisted thoracic surgery (VATS) is currently performed to diagnose and treat solitary pulmonary nodules (SPN). However, the intra-operative identification of deep nodules can be challenging with VATS as the lung is difficult to palpate. The aim of the study was to report the utility and the results of pre-operative computed tomography (CT)-guided hook wire localization of SPN. All records of the patients undergoing CT-guided hook wire localization prior to VATS resection for SPN between 2002 and 2013 were reviewed. The efficacy in localizing the nodule, hook wire complications, necessity to convert VATS to thoracotomy and the histology of SPN are reported. One hundred eighty-one patients (90 females, mean age 63 y, range 28-82 y) underwent 187 pulmonary resections after CT-guided hook wire localization. The mean SPN diameter was 10.3 mm (range: 4-29 mm). The mean distance of the lesion from the pleural surface was 11.6 mm (range: 0-45 mm). The mean time interval from hook wire insertion to VATS resection was 224 min (range 54-622 min). Hook wire complications included pneumothorax requiring chest tube drainage in 4 patients (2.1%) and mild parenchymal haemorrhage in 11 (5.9%) patients. Migration of the hook wire occurred in 7 patients (3.7%) although it did not affect the success of VATS resection (nodule location guided by the lung puncture site). Three patients underwent additional wedge resection by VATS during the same procedure because no lesion was identified in the surgical specimen. Conversion thoracotomy was required in 13 patients (7 %) for centrally localized lesions (6 patients) and pleural adhesions (7 patients). The mean operative time was 60 min (range 18-135 min). Pathological examination revealed a malignant lesion in 107 patients (59 %). The diagnostic yield was 98.3 %. VATS resection for SPN after CT-guided hook wire localization for SPN is safe and allows for proper diagnosis with a low thoracotomy conversion rate.

Hook plate fixation for acute acromioclavicular dislocations without coracoclavicular ligament reconstruction: a functional outcome study in military personnel.

PubMed

Kumar, Narinder; Sharma, Vyom

2015-08-01

The aim of our study was to evaluate the shoulder function after clavicular hook plate fixation of acute acromioclavicular dislocations (Rockwood type III) in a population group consisting exclusively of high-demand military personnel. This prospective study was carried out at a tertiary care military orthopaedic centre during 2012-2013 using clavicular hook plate for management of acromioclavicular injuries without coracoclavicular ligament reconstruction in 33 patients. All patients underwent routine implant removal after 16 weeks. The functional outcome was assessed at 3, 6 and 12 months after hook plate removal and 2 years from the initial surgery using the Constant Murley and UCLA Scores. All the patients were male serving soldiers and had sustained acromioclavicular joint dislocation (Rockwood type III). Mean age of the patient group was 34.24 years (21-55 years). The mean follow-up period in this study was 23.5 months (20-26 months) after hook plate fixation and an average of 19.9 months (17-22 months) after hook plate removal. The average Constant Score at 3 months after hook plate removal was 60.3 as compared to 83.7 and 90.3 at 6 months and 1 year, respectively, and an average of 91.8 at the last follow-up that was approximately 2 years after initial surgery which was statistically significant (p value <0.05). The UCLA Score was an average of 15.27, 25.9 and 30.1 at 3, 6 months and 1 year, respectively, after removal of hook plate which improved further an average of 32.3 at the last follow-up, which was also statistically significant (p value <0.05). Clavicular hook plate fixation without coracoclavicular ligament reconstruction is a good option for acute acromioclavicular dislocations producing excellent medium-term functional results in high-demand soldiers.

A biomechanical analysis of the self-retaining pedicle hook device in posterior spinal fixation

PubMed Central

van Laar, Wilbert; Meester, Rinse J.; Smit, Theo H.

2007-01-01

Regular hooks lack initial fixation to the spine during spinal deformity surgery. This runs the risk of posterior hook dislodgement during manipulation and correction of the spinal deformity, that may lead to loss of correction, hook migration, and post-operative junctional kyphosis. To prevent hook dislodgement during surgery, a self-retaining pedicle hook device (SPHD) is available that is made up of two counter-positioned hooks forming a monoblock posterior claw device. The initial segmental posterior fixation strength of a SPHD, however, is unknown. A biomechanical pull-out study of posterior segmental spinal fixation in a cadaver vertebral model was designed to investigate the axial pull-out strength for a SPHD, and compared to the pull-out strength of a pedicle screw. Ten porcine lumbar vertebral bodies were instrumented in pairs with two different instrumentation constructs after measuring the bone mineral density of each individual vertebra. The instrumentation constructs were extracted employing a material testing system using axial forces. The maximum pull-out forces were recorded at the time of the construct failure. Failure of the SPHD appeared in rotation and lateral displacement, without fracturing of the posterior structures. The average pull-out strength of the SPHD was 236 N versus 1,047 N in the pedicle screws (P < 0.001). The pull-out strength of the pedicle screws showed greater correlation with the BMC compared to the SPHD (P < 0.005). The SPHD showed to provide a significant inferior segmental fixation to the posterior spine in comparison to pedicle screw fixation. Despite the beneficial characteristics of the monoblock claw construct in a SPHD, that decreases the risk of posterior hook dislodgement during surgery compared to regular hooks, the SPHD does not improve the pull-out strength in such a way that it may provide a biomechanically solid alternative to pedicle screw fixation in the posterior spine. PMID:17203270

Mechanics of plant fruit hooks

PubMed Central

Chen, Qiang; Gorb, Stanislav N.; Gorb, Elena; Pugno, Nicola

2013-01-01

Hook-like surface structures, observed in some plant species, play an important role in the process of plant growth and seed dispersal. In this study, we developed an elastic model and further used it to investigate the mechanical behaviour of fruit hooks in four plant species, previously measured in an experimental study. Based on Euler–Bernoulli beam theory, the force–displacement relationship is derived, and its Young's modulus is obtained. The result agrees well with the experimental data. The model aids in understanding the mechanics of hooks, and could be used in the development of new bioinspired Velcro-like materials. PMID:23365190

The comparative morphology of pit organs in elasmobranchs.

PubMed

Peach, M B; Marshall, N J

2009-06-01

The pit organs of elasmobranchs (sharks, skates and rays) are free neuromasts of the mechanosensory lateral line system. Pit organs, however, appear to have some structural differences from the free neuromasts of bony fishes and amphibians. In this study, the morphology of pit organs was investigated by scanning electron microscopy in six shark and three ray species. In each species, pit organs contained typical lateral line hair cells with apical stereovilli of different lengths arranged in an "organ-pipe" configuration. Supporting cells also bore numerous apical microvilli taller than those observed in other vertebrate lateral line organs. Pit organs were either covered by overlapping denticles, located in open grooves bordered by denticles, or in grooves without associated denticles. The possible functional implications of these morphological features, including modification of water flow and sensory filtering properties, are discussed.

Regulation of Cl^- Channels in Normal and Cystic Fibrosis Airway Epithelial Cells by Extracellular ATP

NASA Astrophysics Data System (ADS)

Stutts, M. J.; Chinet, T. C.; Mason, S. J.; Fullton, J. M.; Clarke, L. L.; Boucher, R. C.

1992-03-01

The rate of Cl^- secretion by human airway epithelium is determined, in part, by apical cell membrane Cl^- conductance. In cystic fibrosis airway epithelia, defective regulation of Cl^- conductance decreases the capability to secrete Cl^-. Here we report that extracytosolic ATP in the luminal bath of cultured human airway epithelia increased transepithelial Cl^- secretion and apical membrane Cl^- permeability. Single-channel studies in excised membrane patches revealed that ATP increased the open probability of outward rectifying Cl^- channels. The latter effect occurs through a receptor mechanism that requires no identified soluble second messengers and is insensitive to probes of G protein function. These results demonstrate a mode of regulation of anion channels by binding ATP at the extracellular surface. Regulation of Cl^- conductance by external ATP is preserved in cystic fibrosis airway epithelia.

50 CFR 622.385 - Commercial trip limits.

Code of Federal Regulations, 2013 CFR

2013-10-01

... commercial vessel permit for king mackerel and a king mackerel gillnet permit have been issued. (B) Hook-and...), and operating under the hook-and-line gear quotas in § 622.384(b)(1)(i)(B)(1) or (b)(1)(i)(B)(2): (1) From July 1, each fishing year, until 75 percent of the respective northern or southern subzone's hook...

50 CFR 622.183 - Area and seasonal closures.

Code of Federal Regulations, 2014 CFR

2014-10-01

... be left on the drum if all gangions and hooks are disconnected and stowed below deck. Hooks cannot be... to the drum must be stowed below deck. (D) Terminal gear (i.e., hook, leader, sinker, flasher, or... closing dates of the fishing season by filing a notification to that effect with the Office of the Federal...

76 FR 12604 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Coastal Migratory Pelagic...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-08

...: Temporary rule; trip limit reduction. SUMMARY: NMFS reduces the trip limit for the hook-and-line component... southern subzones, and established their separate quotas. The king mackerel quota for the hook-and-line... percent of the southern Florida west coast subzone's hook-and- line gear quota has been harvested until a...

50 CFR 679.22 - Closures.

Code of Federal Regulations, 2012 CFR

2012-10-01

...) Bogoslof Pacific cod exemption area. (1) All catcher vessels less than 60 ft (18.3 m) LOA using jig or hook... Pacific cod have been caught by catcher vessels less than 60 ft (18.3 m) LOA using jig or hook-and-line... using jig or hook-and-line gear in the exemption area by notification published in the Federal Register...

50 CFR 622.385 - Commercial trip limits.

Code of Federal Regulations, 2014 CFR

2014-10-01

... commercial vessel permit for king mackerel and a king mackerel gillnet permit have been issued. (B) Hook-and...), and operating under the hook-and-line gear quotas in § 622.384(b)(1)(i)(B)(1) or (b)(1)(i)(B)(2): (1) From July 1, each fishing year, until 75 percent of the respective northern or southern subzone's hook...

50 CFR 679.22 - Closures.

Code of Federal Regulations, 2014 CFR

2014-10-01

...) Bogoslof Pacific cod exemption area. (1) All catcher vessels less than 60 ft (18.3 m) LOA using jig or hook... Pacific cod have been caught by catcher vessels less than 60 ft (18.3 m) LOA using jig or hook-and-line... using jig or hook-and-line gear in the exemption area by notification published in the Federal Register...

Abnormally low hCG in a complete hydatidiform molar pregnancy: The hook effect.

PubMed

Nodler, James L; Kim, Kenneth H; Alvarez, Ronald D

2011-01-01

► The hook effect occurs with extremely high levels of hCG, saturating detection antibodies, leading to falsely low laboratory results. ► In the literature, descriptions of the hook effect are rare in cases of gestational trophoblastic diseases. ► If unrecognized, this can lead to delayed therapy or mismanagement of care.

50 CFR 622.183 - Area and seasonal closures.

Code of Federal Regulations, 2013 CFR

2013-10-01

... be left on the drum if all gangions and hooks are disconnected and stowed below deck. Hooks cannot be... to the drum must be stowed below deck. (D) Terminal gear (i.e., hook, leader, sinker, flasher, or... closing dates of the fishing season by filing a notification to that effect with the Office of the Federal...

50 CFR 679.22 - Closures.

Code of Federal Regulations, 2013 CFR

2013-10-01

...) Bogoslof Pacific cod exemption area. (1) All catcher vessels less than 60 ft (18.3 m) LOA using jig or hook... Pacific cod have been caught by catcher vessels less than 60 ft (18.3 m) LOA using jig or hook-and-line... using jig or hook-and-line gear in the exemption area by notification published in the Federal Register...

50 CFR Table 19 to Part 679 - Seabird Avoidance Gear Codes

Code of Federal Regulations, 2010 CFR

2010-10-01

... AVOIDANCE GEAR OR METHOD. 1 Paired Streamer Lines: Used during deployment of hook-and-line gear to prevent...(e)(4)(iii). 2 Single Streamer Line: Used during deployment of hook-and-line gear to prevent birds... deployment of snap gear to prevent birds from taking hooks. The streamer line consists of three components: a...

The M-T Hook Structure Is Critical for Design of HIV-1 Fusion Inhibitors*

PubMed Central

Chong, Huihui; Yao, Xue; Sun, Jianping; Qiu, Zonglin; Zhang, Meng; Waltersperger, Sandro; Wang, Meitian; Cui, Sheng; He, Yuxian

2012-01-01

CP621-652 is a potent HIV-1 fusion inhibitor peptide derived from the C-terminal heptad repeat of gp41. We recently identified that its N-terminal residues Met-626 and Thr-627 adopt a unique hook-like structure (termed M-T hook) thus stabilizing the interaction of the inhibitor with the deep pocket on the N-terminal heptad repeat. In this study, we further demonstrated that the M-T hook structure is a key determinant of CP621-652 in terms of its thermostability and anti-HIV activity. To directly define the structure and function of the M-T hook, we generated the peptide MT-C34 by incorporating Met-626 and Thr-627 into the N terminus of the C-terminal heptad repeat-derived peptide C34. The high resolution crystal structure (1.9 Å) of MT-C34 complexed by an N-terminal heptad repeat-derived peptide reveals that the M-T hook conformation is well preserved at the N-terminal extreme of the inhibitor. Strikingly, addition of two hook residues could dramatically enhance the binding affinity and thermostability of 6-helix bundle core. Compared with C34, MT-C34 exhibited significantly increased activity to inhibit HIV-1 envelope-mediated cell fusion (6.6-fold), virus entry (4.5-fold), and replication (6-fold). Mechanistically, MT-C34 had a 10.5-fold higher increase than C34 in blocking 6-helix bundle formation. We further showed that MT-C34 possessed higher potency against T20 (Enfuvirtide, Fuzeon)-resistant HIV-1 variants. Therefore, this study provides convincing data for our proposed concept that the M-T hook structure is critical for designing HIV-1 fusion inhibitors. PMID:22879603

New Caledonian crows attend to multiple functional properties of complex tools.

PubMed

St Clair, James J H; Rutz, Christian

2013-11-19

The ability to attend to the functional properties of foraging tools should affect energy-intake rates, fitness components and ultimately the evolutionary dynamics of tool-related behaviour. New Caledonian crows Corvus moneduloides use three distinct tool types for extractive foraging: non-hooked stick tools, hooked stick tools and tools cut from the barbed edges of Pandanus spp. leaves. The latter two types exhibit clear functional polarity, because of (respectively) a single terminal, crow-manufactured hook and natural barbs running along one edge of the leaf strip; in each case, the 'hooks' can only aid prey capture if the tool is oriented correctly by the crow during deployment. A previous experimental study of New Caledonian crows found that subjects paid little attention to the barbs of supplied (wide) pandanus tools, resulting in non-functional tool orientation during foraging. This result is puzzling, given the presumed fitness benefits of consistently orienting tools functionally in the wild. We investigated whether the lack of discrimination with respect to (wide) pandanus tool orientation also applies to hooked stick tools. We experimentally provided subjects with naturalistic replica tools in a range of orientations and found that all subjects used these tools correctly, regardless of how they had been presented. In a companion experiment, we explored the extent to which normally co-occurring tool features (terminal hook, curvature of the tool shaft and stripped bark at the hooked end) inform tool-orientation decisions, by forcing birds to deploy 'unnatural' tools, which exhibited these traits at opposite ends. Our subjects attended to at least two of the three tool features, although, as expected, the location of the hook was of paramount importance. We discuss these results in the context of earlier research and propose avenues for future work.

Physiological response of largemouth bass to angling stress

USGS Publications Warehouse

Gustaveson, A. Wayne; Wydoski, Richard S.; Wedemeyer, Gary A.

1991-01-01

The physiological effects of catch-and-release fishing on largemouth bass Micropterus salmoides from Lake Powell and Mantua Reservoir, Utah, were evaluated, and an estimate of the time needed for recovery from hooking stress was obtained. Fatigue in Lake Powell fish, as indicated by elevated blood lactate, was directly proportional to hooking time (1–5 min) and water temperature, but recovery from the hyperlacticemia was relatively rapid (about 24 h). Hyperglycemia, an indicator of stress hormone production, did not occur in largemouth bass hooked and played for 1–5 min in the coldest water (11–13°C), was moderate in fish hooked and played at l6–20°C, and was severe in fish played for 5 min at 28–30°C. Fish held for recovery in live cages suffered further hyperglycemia, presumably because of the stress of confinement. Ionoregulation, as indicated by relatively stable plasma chloride values, was not immediately affected in largemouth bass caught at water temperatures of 11–13°C or 28–30°C, but an unusual hyperchloremia developed in fish hooked and played at 16–20°C. During recovery, the expected progressive hypochloremia developed. Plasma osmolality was somewhat affected by hooking at all water temperatures tested, but recovery was almost complete within about 8 h. Mantua Reservoir fish were hooked and played only at water temperatures of 23–26°C. The hyperlacticemia and hyperglycemia that occurred were generally more severe than in the Lake Powell fish hooked and played at either 16–20°C or 28–30°C. However, effects on plasma chloride and osmolality were similar to those occurring in Lake Powell fish.

Diagnosis and management of hook of hamate fractures.

PubMed

Kadar, Assaf; Bishop, Allen T; Suchyta, Marissa A; Moran, Steven L

2018-06-01

The purpose of this study was to evaluate the time to diagnosis and management of hook of hamate fractures in an era of advanced imaging. We performed a retrospective study of 51 patients treated for hook of hamate fractures. Patients were sent a quickDASH questionnaire regarding the outcomes of their treatment. Hook of hamate fractures were diagnosed with advanced imaging at a median of 27 days. Clinical findings of hook of hamate tenderness had better sensitivity than carpal tunnel-view radiographs. Nonunion occurred in 24% of patients with non-operative treatment and did not occur in the operative group. Both treatment groups achieved good clinical results, with a grip strength of 80% compared with the non-injured hand and a median quickDASH score of 2. Advanced imaging improved the time to diagnosis and treatment compared to historical case series. Nonunion is common in patients treated non-operatively. IV.

Bohlin transformation: the hidden symmetry that connects Hooke to Newton

NASA Astrophysics Data System (ADS)

Saggio, Maria Luisa

2013-01-01

Hooke's name is familiar to students of mechanics thanks to the law of force that bears his name. Less well-known is the influence his findings had on the founder of mechanics, Isaac Newton. In a lecture given some twenty years ago, W Arnol'd pointed out the outstanding contribution to science made by Hooke, and also noted the controversial issue of the attribution of important discoveries to Newton that were actually inspired by Hooke. It therefore seems ironic that the two most famous force laws, named after Hooke and Newton, are two geometrical aspects of the same law. This relationship, together with other illuminating aspects of Newtonian mechanics, is described in Arnol'd's book and is worth remembering in standard physics courses. In this didactical paper the duality of the two forces is expounded and an account of the more recent contributions to the subject is given.

Comparison of morphological characters in Irish and English populations of the acanthocephalan Pomphorhynchus laevis (Müller, 1776).

PubMed

O'Mahony, E M; Kennedy, C R; Holland, C V

2004-10-01

Pomphorhynchus laevis is believed on ecological evidence to exist as three strains in the British Isles. However, the strains have never been shown to be capable of being distinguished using morphological characters. A morphological comparison was made between a sample of P. laevis from Salmo trutta in L. Feeagh in the west of Ireland and a sample from Leuciscus cephalus in R. Culm in the south of England. The length and width of the trunk, neck, bulb, proboscis and hooks were measured. The number of hooks per row, the number of rows and the positions of the stoutest and longest hooks were also recorded. A Principal Components Analysis based on the morphological measurements confirmed the separation of the two populations and showed that two characters successfully identified the populations: the position of the stoutest hook and the ratio of numbers of anterior to posterior hooks.

33 CFR 334.102 - Sandy Hook Bay, Naval Weapons Station EARLE, Piers and Terminal Channel, restricted area...

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Sandy Hook Bay, Naval Weapons... DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.102 Sandy Hook Bay, Naval Weapons Station EARLE, Piers..., shall be enforced by the Commanding Officer, Naval Weapons Station Earle, and/or other persons or...

33 CFR 334.102 - Sandy Hook Bay, Naval Weapons Station EARLE, Piers and Terminal Channel, restricted area...

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Sandy Hook Bay, Naval Weapons... DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.102 Sandy Hook Bay, Naval Weapons Station EARLE, Piers..., shall be enforced by the Commanding Officer, Naval Weapons Station Earle, and/or other persons or...

33 CFR 334.102 - Sandy Hook Bay, Naval Weapons Station EARLE, Piers and Terminal Channel, restricted area...

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Sandy Hook Bay, Naval Weapons... DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.102 Sandy Hook Bay, Naval Weapons Station EARLE, Piers..., shall be enforced by the Commanding Officer, Naval Weapons Station Earle, and/or other persons or...

33 CFR 334.102 - Sandy Hook Bay, Naval Weapons Station EARLE, Piers and Terminal Channel, restricted area...

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Sandy Hook Bay, Naval Weapons... DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.102 Sandy Hook Bay, Naval Weapons Station EARLE, Piers..., shall be enforced by the Commanding Officer, Naval Weapons Station Earle, and/or other persons or...

33 CFR 334.102 - Sandy Hook Bay, Naval Weapons Station EARLE, Piers and Terminal Channel, restricted area...

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 false Sandy Hook Bay, Naval Weapons... DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.102 Sandy Hook Bay, Naval Weapons Station EARLE, Piers..., shall be enforced by the Commanding Officer, Naval Weapons Station Earle, and/or other persons or...

Morphological and histochemical demonstration of hooks in the rostellar region of Cysticercus bovis.

PubMed

Zdárská, Z

1976-01-01

Hooklets and early developmental stages of hooks were discovered in the tegument among the microtriches in the rostellar region of 83- and 108-day-old Cysticercus bovis. The cortical layer of hooks consists of proteins with tyrosine and SS groups. The rostellar sac and bulb are distinctly developed in the parenchyma of the rostellar region.

46 CFR 173.025 - Additional intact stability standards: Counterballasted vessels.

Code of Federal Regulations, 2014 CFR

2014-10-01

... of heel. T=angle of heel. EC01MR91.028 Where— GZ(1) is the righting arm curve at the displacement corresponding to the vessel without hooking load. GZ(2) is the righting arm curve at the displacement... of the hook load and the counterballast at the displacement with hook load. HA(2) is the heeling arm...

46 CFR 173.025 - Additional intact stability standards: Counterballasted vessels.

Code of Federal Regulations, 2012 CFR

2012-10-01

... of heel. T=angle of heel. EC01MR91.028 Where— GZ(1) is the righting arm curve at the displacement corresponding to the vessel without hooking load. GZ(2) is the righting arm curve at the displacement... of the hook load and the counterballast at the displacement with hook load. HA(2) is the heeling arm...

46 CFR 173.025 - Additional intact stability standards: Counterballasted vessels.

Code of Federal Regulations, 2011 CFR

2011-10-01

... of heel. T=angle of heel. EC01MR91.028 Where— GZ(1) is the righting arm curve at the displacement corresponding to the vessel without hooking load. GZ(2) is the righting arm curve at the displacement... of the hook load and the counterballast at the displacement with hook load. HA(2) is the heeling arm...

46 CFR 173.025 - Additional intact stability standards: Counterballasted vessels.

Code of Federal Regulations, 2013 CFR

2013-10-01

... of heel. T=angle of heel. EC01MR91.028 Where— GZ(1) is the righting arm curve at the displacement corresponding to the vessel without hooking load. GZ(2) is the righting arm curve at the displacement... of the hook load and the counterballast at the displacement with hook load. HA(2) is the heeling arm...

46 CFR 173.025 - Additional intact stability standards: Counterballasted vessels.

Code of Federal Regulations, 2010 CFR

2010-10-01

... of heel. T=angle of heel. EC01MR91.028 Where— GZ(1) is the righting arm curve at the displacement corresponding to the vessel without hooking load. GZ(2) is the righting arm curve at the displacement... of the hook load and the counterballast at the displacement with hook load. HA(2) is the heeling arm...

75 FR 2469 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Reef Fish Fishery of the Gulf of...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-15

... more than 750 hooks rigged for fishing or fished at any given time. The intended effect of the... these alternatives would result in lower adverse economic effects than the proposed hook restriction is... lower hook limit would be expected to result in greater adverse economic effects than the proposed limit...

The "hook effect" causing a negative pregnancy test in a patient with an advanced molar pregnancy.

PubMed

Winder, Abigail D; Mora, Adria Suarez; Berry, Emily; Lurain, John R

2017-08-01

•At high hCG levels in molar pregnancies, a "hook effect" can cause an artificially negative value.•Delay in diagnosis of a molar pregnancy due to the "hook effect" can lead to severe complications.•Suspicion of a molar pregnancy should be communicated so a diluted sample is used to quantify hCG.

77 FR 61295 - Snapper-Grouper Fishery off the Southern Atlantic States; Snapper-Grouper Management Measures

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-09

...), gutted weight, to ensure that the hook-and-line component of the commercial sector has the opportunity to... hook-and-line quota is not met by September 1, boats with longline endorsements should be able to participate in the hook-and-line component of the commercial sector, using bandit reels, under a 500 lb (227...

75 FR 80720 - Magnuson-Stevens Act Provisions; Fisheries of the Northeastern United States; Northeast...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-23

... (GB) when fishing under a groundfish/monkfish DAS; (6) limits on the number of hooks that may be... groundfish/monkfish DAS; (7) limits on the number of hooks that may be fished; and (8) DAS Leasing Program.... 7. Limitation on the Number of Hooks That May Be Fished The GB Cod Fixed Gear Sector was granted an...

75 FR 6318 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Coastal Migratory Pelagic...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-09

...: Temporary rule; trip limit reduction. SUMMARY: NMFS reduces the trip limit in the commercial hook-and-line... separate quotas. The quota for the hook-and-line fishery in the southern Florida west coast subzone is 520...), from the date that 75 percent of the southern Florida west coast subzone's hook-and- line gear quota...

78 FR 15642 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Coastal Migratory Pelagic...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-12

...: Temporary rule; trip limit reduction. SUMMARY: NMFS reduces the trip limit in the hook-and-line component of... their separate quotas. The 2012 to 2013 fishing year quota for the hook-and-line component of the... southern Florida west coast subzone's hook-and- line gear quota has been harvested until a closure of the...

50 CFR 622.44 - Commercial trip limits.

Code of Federal Regulations, 2012 CFR

2012-10-01

... been issued. (B) Hook-and-line gear. In the Florida west coast subzone, king mackerel in or from the... required by § 622.4(a)(2)(iii), and operating under the hook-and-line gear quotas in § 622.42(c)(1)(i)(A)(2... northern or southern subzone's hook-and-line gear quota has been harvested—in amounts not exceeding 1,250...

50 CFR 622.44 - Commercial trip limits.

Code of Federal Regulations, 2011 CFR

2011-10-01

... been issued. (B) Hook-and-line gear. In the Florida west coast subzone, king mackerel in or from the... required by § 622.4(a)(2)(iii), and operating under the hook-and-line gear quotas in § 622.42(c)(1)(i)(A)(2... northern or southern subzone's hook-and-line gear quota has been harvested—in amounts not exceeding 1,250...

Terrain Traversing Device Having a Wheel with Microhooks

NASA Technical Reports Server (NTRS)

Wiltsie, Nicholas (Inventor); Carpenter, Kalind C. (Inventor); Parness, Aaron (Inventor)

2015-01-01

A terrain traversing device is described. The device includes an annular rotor element with a plurality of co-planar microspine hooks arranged on the periphery of the annular rotor element. Each microspine hook has an independently flexible suspension configuration that permits the microspine hook to initially engage an irregularity in a terrain surface at a preset initial engagement angle and subsequently engage the irregularity with a continuously varying engagement angle when the annular rotor element is rotated for urging the terrain traversing device to traverse a terrain surface. Improvements related to the design, fabrication and use of the microspine hooks in the device are also described.

Hooking-Up, Religiosity, and Sexting Among College Students.

PubMed

Hall, Michael; Williams, Ronald D; Ford, M Allison; Cromeans, Erin Murphy; Bergman, Randall J

2016-07-28

The purpose of this study was to evaluate the mediation effect of sexting, and taking sexually suggestive photos on religiosity and hooking-up with three separate sexual outcomes. A web-based survey examined the relationship between religiosity and the three hooking-up outcomes among students reporting sexting or taking a sexually suggestive photo in the last 30 days (n = 231). Sexting, as well as taking sexually suggestive photos mediated the relationship between religiosity and hooking-up among females. Sexting may be initiated by females as a way to engage in a nonphysical sexual interaction, which ultimately predisposes them to a physical sexual outcome.

The remarkable vision of Robert Hooke (1635-1703): first observer of the microbial world.

PubMed

Gest, Howard

2005-01-01

Robert Hooke played important roles in the early development of the Royal Society of London. As Curator of Experiments of the Society, he became a pioneering microscopist, prolific inventor, astronomer, geologist, architect, and an effective surveyor of the City of London following the Great Fire of 1666. Hooke's Micrographia (1665) revealed the microscopic structures of numerous biological and inorganic objects and became an important source of information for later studies. Aside from the body of detailed observations reported and depicted in Micrographia, the Preface is in itself an extraordinary document that exhibits Hooke's fertile mind, philosophical insights, and rare ability to look into the future.

Application of Rubber Band with Hooks on Both Ends for Vagus Nerve Stimulator Implantation.

PubMed

Hosoyama, Hiroshi; Hanaya, Ryosuke; Otsubo, Toshiaki; Sato, Masanori; Kashida, Yumi; Sugata, Sei; Katagiri, Masaya; Iida, Koji; Arita, Kazunori

2018-03-01

Vagus nerve stimulation (VNS) is a valuable therapeutic option for many types of drug-resistant epilepsy. Muscle hooks and carotid endarterectomy rings have been used for cervical delamination preceding the implantation of stimulation electrodes. The attachment on both sides of a rubber band of Kamiyama-style hanging needles, as are used for scalp and dural retraction during craniotomy, yields a useful tool for VNS implantation. Here we report our experience with this method. We present our method using a rubber band plus hooks and a review of 21 consecutive patients who underwent VNS implantation using our rubber band-plus-hooks method. None of the 21 patients experienced intraoperative or perioperative complications. Hooks placed in connective tissue around the common carotid artery and jugular vein raised the vagus nerve by elevating the carotid sheath. A single surgeon was able to perform all cervical manipulations under a surgical microscope. The average operation time in this series of 21 patients was 137 minutes. The use of hooks attached to both sides of a rubber band rendered VNS implantation safer by lifting the vagus nerve and standardizing the procedure. Copyright © 2017 Elsevier Inc. All rights reserved.

Improvement for identification of heterophile antibody interference and AFP hook effect in immunoassays with multiplex suspension bead array system.

PubMed

Wang, Yajie; Yu, Jinsheng; Ren, Yuan; Liu, Li; Li, Haowen; Guo, Anchen; Shi, Congning; Fang, Fang; Juehne, Twyla; Yao, Jianer; Yang, Enhuan; Zhou, Xuelei; Kang, Xixiong

2013-11-15

A variety of immunoassays including multiplex suspension bead array have been developed for tumor marker detections; however, these assays could be compromised in their sensitivity and specificity by well-known heterophile antibody interference and hook effect. Using Luminex® multiplex suspension bead arrays, we modified protocols with two newly-developed solutions that can identify heterophile antibody interference and AFP hook effect. Effectiveness of the two solutions was assessed in serum samples from patients. Concentrations of 9 tumor markers in heterophile antibody positive samples assayed with Solution A, containing murine monoclonal antibodies and mouse serum, were significantly reduced when compared with those false high signals assayed without Solution A (all p<0.01). With incorporation of Solution H (fluorescent beads linked with AFP antigen), a new strategy for identification of AFP hook effect was established, and with this strategy AFP hook effect was identified effectively in serum samples with very high levels of AFP. Two proprietary solutions improve the identification of heterophile antibody interference and AFP hook effect. With these solutions, multiplex suspension bead arrays provide more reliable testing results in tumor marker detection where complex clinical serum samples are used. © 2013.

[Complications of treatment of acromioclavicular joint dislocation and unstable distal clavicular fracture with clavicular hook plate].

PubMed

Zhu, Yi-Yong; Cui, Heng-Yan; Jiang, Pan-Qiang; Wang, Jian-Liang

2013-11-01

To investigate the causes and prevention of the complications about treatment of acromioclavicular joint dislocation (Tossy III) and unstable distal clavicular fracture (Neer II) with clavicular hook plate. From January 2001 to December 2011, 246 patients with acromioclavicular joint dislocation (Tossy III) and 222 patients with unstable distal clavicular fracture (Neer II) were treated with acromioclvicular hook plate fixation,including 348 males and 120 females with an average age of 45.4 years old ranging from 21 to 80 years old. The mean time from injury to operation was 30.8 hours (ranged from 1 h to 15 d). All patients had normal shoulder function before injury. According to Karlsson evaluation standard, the cases with excellent and good function of the shoulder joint were regarded as the normal group, and the cases with poor function of shoulder joint as the abnormal group. The comparison of the range of forward flexion,backward stretch, adduction, abduction and elevation of shoulder joints between two groups was performed. The data of impingement, subacromial osteolysis, acromioclavicular arthritis, clavicular stress fracture, downward acromioclavicular joint subluxation, hook cut-out and hook break were summarized. All patients were followed up from 8 to 48 months with an average of 12.5 months. The results were excellent in 308 cases,good in 76,and poor in 84 according to Karlsson evaluation. The excellent and good rate was 82.1%. The difference of the range of forward flexion, backward stretch, adduction, abduction and elevation of shoulder joints between two groups had a statistically significant difference (P < 0.01). Among 84 poor cases, there were 41 (8.76%) in acromial impingement or inadequate place of plate hook, 12 (2.56%) with subacromial osteolysis or/and bursitis, 10 (2.14%) with acromioclavicular arthritis or painful shoulder caused by delayed dirigation,7 (1.50%) with clavicular stress fracture or interal plate upward, 6 (1.28%) with downward acromioclavicular joint subluxation, 5 (1.07%) with hook cut -out and 3 (0.64%) in hook break. The clavicular hook plate is useful for the treatment of acromioclavicular joint dislocation (Tossy III) and unstable distal clavicular fracture (Neer II). The correct place and suitable preflex of plate hook,the restoration of fiber structure around the acromioclavicular joint and the advisable dirigation contribute to the modified rate of complications.

Effect of apical meristem clipping on carbon allocation and morphological development of white oak seedlings

Treesearch

Paul P. Kormanik; Shi-Jean S. Sung; T.L. Kormanik; Stanley J. Zarnoch

1994-01-01

Seedlings from three open-pollinated half-sib white oak seedlots were clipped in mid-July and their development was compared to nonclipped controls after one growing season.In general when data were analyzed by family, clipped seedlings were significantly less desirable in three to six of the eight variables tested.Numerically, in all families seedlots, the clipped...

Surgical treatment of acute acromioclavicular joint dislocations: hook plate versus minimally invasive reconstruction.

PubMed

Metzlaff, S; Rosslenbroich, S; Forkel, P H; Schliemann, B; Arshad, H; Raschke, M; Petersen, W

2016-06-01

This study was performed to compare the clinical results of a minimally invasive technique for acute acromioclavicular (AC) joint dislocation repair with the traditional hook plate fixation. Forty-four patients with an acute (within 2 weeks after trauma) complete AC joint separation (35 male, nine female; median age 36.2 years, range 18-56) underwent surgical repair with either a minimally invasive AC joint repair or a conventional hook plate. Functional outcome was evaluated using the Constant-Murley Score (CMS), the TAFT score and the AC joint instability score (ACJI). Radiographic evaluation was performed with bilateral anterior-posterior (a.p.) stress and Alexander views. All patients were available after a median follow-up of 32 months (range 24-51). There were no significant differences in the mean CMS, Taft score and the ACJI between the two groups. The radiological assessment revealed no significant difference in the coracoclavicular distance. In both groups, a slight loss of reduction was observed. Periarticular ossification was seen in 11 patients of the minimally invasive AC joint repair and eight patients of the hook plate group but this did not affect the final outcome. Hook plates were removed after a median interval of 11.9 weeks (range 10-13). Good clinical results can be achieved with both minimally invasive AC joint repair and hook plate fixation. However, in the hook plate group a second operation is mandatory for plate removal. III.

[Case-control study on endobutton plate or clavicular hook plate for the repair of acromioclavicular joint dislocations].

PubMed

Zhu, Li; Yang, He-Jie; Zhao, Wan-Jun; Yang, Wu-Min; Zhou, Hui

2012-02-01

To compare the treatment results between Endobutton plate and clavicular hook plate for the treatment of acromioclavicular joint dislocations. From January 2009 to September 2010, 30 patients with acromioclavicular joint dislocations were treated with two different fixations: Endobutton plate (15 patients, including 12 males and 3 females, with a mean age of 38.5 +/- 8.2 years) and clavicular hook plate (15 patients, including 14 males and 1 female, with the mean age of 33.8 +/- 5.9 years). The mean operative time and blood loss were compared between the two groups. Joint function was assessed by the Karlsson standard. The mean operative time of the Endobutton group and the hook plate group were (61 +/- 8.6) min and (40 +/- 5.6) min. The average blood loss were (93 +/- 8.4) ml and (100 +/- 12.6) ml. There was no statistical difference between the two groups in the average blood loss and the mean operative time. According to the Karlsson standard, 13 patients got an excellent result, 2 good in the Endobutton group; and 7 patients got an excellent result and 7 good in hook plate group. The therapeutic effect in Endobutton group was better than that of hook plate group. In the treatment of acromioclavicular dislocation, fixation with Endobutton plate is believed to be better than hook plate fixation. It is an effective method for the repair of acromioclavicular joint dislocations in a short term. But its long term effects still need further follow up.

Is the apical soft tissue margin a better predictor of biochemical recurrence than the surgical specimen?

PubMed

Godoy, Guilherme; Tareen, Basir U; Lepor, Herbert

2011-01-01

To identify predictors of apical surgical margin (ASM) and apical soft tissue margin (ASTM), determine if the ASTM is a better predictor of biochemical recurrence (BR) than the ASM, and ascertain the impact of apical biopsies on BR rates. One thousand three hundred eight consecutive men underwent open radical retropubic prostatectomy (RP) between October 2000 and December 2006. Circumferential biopsies of the ASTM were obtained intraoperatively and submitted for frozen section analysis. Logistic regression models were utilized to identify the factors associated with the presence of positive ASMs and ASTMs. The estimated 5-year risk of BR was calculated by the Kaplan-Meier method. Overall, 43 (3.3%) and 86 (6.6%) of cases exhibited positive ASM and ASTM, respectively. ASM was significantly associated with higher mean serum prostate-specific antigen levels, presence of perineural invasion, and greater volume of tumor in the biopsy specimen. None of these factors were observed to be associated with the presence of cancer in the ASTMs. In the multivariate analysis, only the presence of perineural invasion was a significant independent predictor of ASMs. The estimated 5-year BR rates in the positive ASMs only, ASTMs only, and both positive ASMs and ASTMs groups were 48.6%, 4.7%, and 38.8%, respectively. A positive ASM was associated with a significantly greater risk of BR compared with a positive ASTM. The very low estimated risk of BR at 5 years in cases with ASTM suggests that performing the ASTM biopsies may increase the cure rates achieved with RP. Copyright © 2011 Elsevier Inc. All rights reserved.

76 FR 29671 - Fisheries of the Exclusive Economic Zone Off Alaska; Reallocation of Pacific Cod in the Bering...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-23

... gear to catcher vessels less than 60 feet (18.3 meters) length overall using hook-and-line or pot gear... catcher vessel apportionment to catcher vessels less than 60 feet length overall (LOA) using hook-and-line... feet LOA using hook-and-line or pot gear. Classification This action responds to the best available...

75 FR 7403 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using Hook...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-19

.... 0810141351-9087-02] RIN 0648-XU36 Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using Hook-and-Line Gear in the Bering Sea and Aleutian Islands Management Area AGENCY: National... using hook-and-line gear in the Bering Sea and Aleutian Islands management area (BSAI). This action is...

76 FR 28169 - Airworthiness Directives; Agusta S.p.A. Model AB412 Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-16

... lock pin may cause the loss of the hoist hook and any load. The absence of the lock pin constitutes an... cause the loss of the hoist hook and any load. The absence of the lock pin constitutes an unsafe... absence of this lock pin to prevent the loss of a rescue hoist hook and its load. [[Page 28171

Photocopy of plan (in collection of U.S. Coast Guard Civil ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Photocopy of plan (in collection of U.S. Coast Guard Civil Engineering Unit Providence, Warwick, RI), U.S. Coast Guard Civil Engineering, third district, marine railway, Sandy Hook Station, Ft. Hancock, Sandy Hook, NJ, repairs, plan sections & framing details, wharf B - U.S. Coast Guard Sandy Hook Station, Western Docking Structure, West of intersection of Canfield Road & Hartshorne Drive, Highlands, Monmouth County, NJ

77 FR 65356 - Fisheries of the Caribbean, Gulf of Mexico and South Atlantic; Snapper-Grouper Fishery Off the...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-26

... commercial annual catch limit (ACL) between the longline and hook-and-line components. Seventy-five percent... and 25 percent of the ACL, or 135,324 lb (61,382 kg), gutted weight, would be allocated to the hook... trip limit was originally intended to allow hook-and-line fishermen access to golden tilefish in the...

Zero-stress states of human pulmonary arteries and veins.

PubMed

Huang, W; Yen, R T

1998-09-01

The zero-stress states of the pulmonary arteries and veins from order 3 to order 9 were determined in six normal human lungs within 15 h postmortem. The zero-stress state of each vessel was obtained by cutting the vessel transversely into a series of short rings, then cutting each ring radially, which caused the ring to spring open into a sector. Each sector was characterized by its opening angle. The mean opening angle varied between 92 and 163 degrees in the arterial tree and between 89 and 128 degrees in the venous tree. There was a tendency for opening angles to increase as the sizes of the arteries and veins increased. We computed the residual strains based on the experimental measurements and estimated the residual stresses according to Hooke's law. We found that the inner wall of a vessel at the state in which the internal pressure, external pressure, and longitudinal stress are all zero was under compression and the outer wall was in tension, and that the magnitude of compressive stress was greater than the magnitude of tensile stress.

Evolved to fail: Bacteria induce flagellar buckling to reorient

NASA Astrophysics Data System (ADS)

Son, Kwangmin; Guasto, Jeffrey S.; Stocker, Roman

2012-11-01

Many marine bacteria swim with a single helical flagellum connected to a rotary motor via a 100 nm long universal joint called the ``hook.'' While these bacteria have seemingly just one degree of freedom, allowing them to swim only back and forth, they in fact exhibit large angular reorientations mediated by off-axis ``flicks'' of their flagellum. High-speed video microscopy revealed the mechanism underpinning this turning behavior: the buckling of the hook during the exceedingly brief (10 ms) forward run that follows a reversal. Direct measurements of the hook's mechanical properties corroborated this result, as the hook's structural stability is governed by the Sperm number, which compares the compressive load from propulsion to the elastic restoring force of the hook. Upon decreasing the Sperm number below a critical value by reducing the swimming speed, the frequency of flicks diminishes sharply, consistent with the criticality of buckling. This elegant, under-actuated turning mechanism appears widespread among marine bacteria and may provide a novel design concept in micro-robotics.

Can hook-bending be let off the hook? Bending/unbending of pliant tools by cockatoos.

PubMed

Laumer, I B; Bugnyar, T; Reber, S A; Auersperg, A M I

2017-09-13

The spontaneous crafting of hook-tools from bendable material to lift a basket out of a vertical tube in corvids has widely been used as one of the prime examples of animal tool innovation. However, it was recently suggested that the animals' solution was hardly innovative but strongly influenced by predispositions from habitual tool use and nest building. We tested Goffin's cockatoo, which is neither a specialized tool user nor a nest builder, on a similar task set-up. Three birds individually learned to bend hook tools from straight wire to retrieve food from vertical tubes and four subjects unbent wire to retrieve food from horizontal tubes. Pre-experience with ready-made hooks had some effect but was not necessary for success. Our results indicate that the ability to represent and manufacture tools according to a current need does not require genetically hardwired behavioural routines, but can indeed arise innovatively from domain general cognitive processing. © 2017 The Authors.

The maxillary molar endodontic access opening: A microscope-based approach

PubMed Central

Mamoun, John Sami

2016-01-01

This article reviews the basic clinical techniques of performing a maxillary molar endodontic access opening, starting from the initial access opening into the pulp chamber, to the point where a size #10 file has been advanced to the apices of all three or four (or more) canals. The article explains how the use of the dental surgical operating microscope or microscope-level loupes magnification of ×6–8 or greater, combined with head-mounted or coaxial illumination, improve the ability of a dentist to identify microscopic root canal orifices, which facilitates the efficient creation of conservative access openings with adequate straight-line access in maxillary molars. Magnified photos illustrate various microscopic anatomical structures or landmarks of the initial access opening. Techniques are explored for implementing an access opening for teeth with vital versus necrotic pulpal tissues. The article also explores the use of piezoelectric or ultrasonic instruments for revealing root canal orifices and for removing pulp stones or calcified pulpal tissue inside the pulp chamber. PMID:27403069

77 FR 53152 - Fisheries of the Exclusive Economic Zone Off Alaska; Reallocation of Pacific Cod in the Bering...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-31

... gear, catcher vessels greater than 60 feet (18.3 meters) length overall (LOA) using hook-and-line gear, and catcher vessels using trawl gear to catcher vessels less than 60 feet (18.3 meters) LOA using hook... than 60 feet (18.3 meters(m)) LOA using hook-and- line or pot gear. The 2012 Pacific cod TAC specified...

78 FR 59908 - Fisheries of the Exclusive Economic Zone Off Alaska; Bering Sea and Aleutian Islands Management...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-30

... authorizing a designated vessel to catch and process Pacific cod in the BSAI hook-and-line fisheries to use... (MLOA) to 220 feet (67 m) on LLP licenses authorizing vessels to catch and process Pacific cod with hook... cod with hook-and-line and pot gear in the BSAI to increase the MLOA on the LLP license to 220 feet...

Discovery of a vezatin-like protein for dynein-mediated early endosome transport

PubMed Central

Yao, Xuanli; Arst, Herbert N.; Wang, Xiangfeng; Xiang, Xin

2015-01-01

Early endosomes are transported bidirectionally by cytoplasmic dynein and kinesin-3, but how the movements are regulated in vivo remains unclear. Here our forward genetic study led to the discovery of VezA, a vezatin-like protein in Aspergillus nidulans, as a factor critical for early endosome distribution. Loss of vezA causes an abnormal accumulation of early endosomes at the hyphal tip, where microtubule plus ends are located. This abnormal accumulation depends on kinesin-3 and is due to a decrease in the frequency but not the speed of dynein-mediated early endosome movement. VezA-GFP signals are enriched at the hypha tip in an actin-dependent manner but are not obviously associated with early endosomes, thus differing from the early endosome association of the cargo adapter HookA (Hook in A. nidulans). On loss of VezA, HookA associates normally with early endosomes, but the interaction between dynein-dynactin and the early-endosome-bound HookA is significantly decreased. However, VezA is not required for linking dynein-dynactin to the cytosolic ∆C-HookA, lacking the cargo-binding C-terminus. These results identify VezA as a novel regulator required for the interaction between dynein and the Hook-bound early endosomes in vivo. PMID:26378255

Gap compression/extension mechanism of bacterial flagellar hook as the molecular universal joint.

PubMed

Furuta, Tadaomi; Samatey, Fadel A; Matsunami, Hideyuki; Imada, Katsumi; Namba, Keiichi; Kitao, Akio

2007-03-01

Bacterial flagellar hook acts as a molecular universal joint, transmitting torque produced by the flagellar basal body, a rotary motor, to the flagellar filament. The hook forms polymorphic supercoil structures and can be considered as an assembly of 11 circularly arranged protofilaments. We investigated the molecular mechanism of the universal joint function of the hook by a approximately two-million-atom molecular dynamics simulation. On the inner side of the supercoil, protein subunits are highly packed along the protofilament and no gaps remain for further compression, whereas subunits are slightly separated and are hydrogen bonded through one layer of water molecules on the outer side. As for the intersubunit interactions between protofilaments, subunits are packed along the 6-start helix in a left-handed supercoil whereas they are highly packed along the 5-start helix in a right-handed supercoil. We conclude that the supercoiled structures of the hook in the left- and right-handed forms make maximal use of the gaps between subunits, which we call "gap compression/extension mechanism". Mutual sliding of subunits at the subunit interface accompanying rearrangements of intersubunit hydrogen bonds is interpreted as a mechanism to allow continuous structural change of the hook during flagellar rotation at low energy cost.

The hook effect in calcitonin immunoradiometric assay: a case report.

PubMed

Fangous, Marie-Sarah; Kerspern, Hélène; Moineau, Marie-Pierre; Kerlan, Véronique; Alavi, Zarrin; Carré, Jean-Luc

2012-12-01

The hook effect, which has long been detected and documented for immunoradiometric assays (IRMA) such as those measuring prolactin or thyroglobulin, occurs when the serum antigen level is extremely high, thus inducing a bias in the methodology of measurement. We report the case of an 80-year-old man with confirmed medullary thyroid carcinoma (MTC). In the case reported here, the clinical status of the patient contrasts with his tumor antigen, serum calcitonin (CT), concentrations. The measured increased CT concentrations revealed the presence of a hook effect. This phenomenon occurs due to an excess of antigen during the one-step IRMA where the signal antibodies, bound to the non-captured antigens, are washed out during the measurement, inducing the loss of signal. Aiming to prevent the "hook effect", successive dilutions of the same sample of serum were done. Previous studies have shown when one-step IRMA reveals high concentrations of a tumor serum antigen (i.e. prolactin or thyroglobulin), a two-step IRMA or a systematic 1:10 dilution of the serum sample prevents the formation of the "hook effect". In our case report, the CT "hook effect" formation was prevented by performing serial dilutions of the serum sample. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

Arthroscopic evaluation for omalgia patients undergoing the clavicular hook plate fixation of distal clavicle fractures

PubMed Central

2014-01-01

Background The aim of this study is to investigate the anatomic changes in the shoulder joints responsible for omalgia after the clavicular hook plate fixation under arthroscope. Methods Arthroscopic examination was carried out for 12 omalgia patients who underwent clavicular hook plate fixation due to distal clavicle fractures. Functional outcome of shoulder was measured by the Japanese Orthopaedic Association (JOA) score before and after the withdrawal of the fixation plate. Results The rotator cuff compression by the clavicular hook was arthroscopically observed in 11 of the 12 cases. The JOA scores of the shoulder were significantly improved at 1 month after the withdrawal of the fixation plate (pain, 28 ± 2.4 vs. 15 ± 5.2; function, 19.2 ± 1.0 vs. 11.7 ± 1.9; range of movements, 26.8 ± 2.6 vs. 14.8 ± 3.4) compared with before. Conclusions The impingement of the hook to the rotator cuff may be the main cause for the omalgia. The appropriate hook and plate that fit to the curve of the clavicle as well as the acromion are necessary to decrease the severity of omalgia. PMID:24917508

The influence of pornography on sexual scripts and hooking up among emerging adults in college.

PubMed

Braithwaite, Scott R; Coulson, Gwen; Keddington, Krista; Fincham, Frank D

2015-01-01

The explosive growth in access to the Internet has led to a commensurate increase in the availability, anonymity, and affordability of pornography. An emerging body of research has shown associations between pornography and certain behaviors and attitudes; yet, how pornography actually influences these outcomes has not been documented. In two studies (Study 1 N = 969; Study 2 N = 992) we examined the hypothesis that pornography influences potentially risky sexual behavior (hooking up) among emerging adults via sexual scripts. Our results demonstrate that more frequent viewing of pornography is associated with a higher incidence of hooking up and a higher number of unique hook up partners. We replicated these effects both cross-sectionally and longitudinally while accounting for the stability of hook ups over the course of an academic semester. We also demonstrated that more frequent viewing of pornography is associated with having had more previous sexual partners of all types, more one occasion sexual partners ("one night stands"), and plans to have a higher number of sexual partners in the future. Finally, we provided evidence that more permissive sexual scripts mediated the association between more frequent pornography viewing and hooking up. We discuss these findings with an eye toward mitigating potential personal and public health risks among emerging adults.

Ultrastructure of the external gill epithelium of the axolotl, Ambystoma mexicanum with reference to ionic transport.

PubMed

Jarial, M S; Wilkins, J H

2003-10-01

The ultrastructure of the external gill epithelium of the axolotl, Ambystoma mexicanum, has been examined using conventional transmission electron microscopy to elucidate its role in ionic transport. Four cell types are identified in the gill filament and primary gill bar epithelium. These are granular, ciliated, Leydig and basal cells. A fifth cell type, the flat mitochondria-rich cell is only found in the gill bar epithelium. The predominant granular cells display microvilli at their surface and their cytoplasm contains abundant mitochondria, rough endoplasmic reticulum, Golgi complexes, vesicles and PAS+ secretory granules that are extruded at the surface, which along with secretions from the Leydig cells form a mucous coat. The granular cells are joined apically by junctional complexes consisting of zonulae occludens, zonulae adherens and desmosomes. The lateral membranes of granular cells enclose large intercellular spaces that are closed at the apical ends but remain open at the basal ends adjoining capillaries. In AgNO3-treated axolotl, the gills become darkly stained, the silver grains penetrate apical membranes and appear in the cytoplasm, accumulating near the lateral membranes and also enter the intercellular spaces. These findings are consistent with the dual role of the gill epithelium in mucus production and active ionic transport.

Nonsurgical Management of an Immature Maxillary Central Incisor with Type III Dens Invaginatus Using MTA Plug: A Case Report

PubMed Central

Norouzi, Negar; Kazem, Majid; Gohari, Atefeh

2017-01-01

Dens invaginatus is a developmental anomaly, caused by deepening of the enamel organ into the dental papilla before calcification of the dental tissues. Teeth with dens invagination are susceptible to early caries and pulp necrosis within a few years of eruption or even before root end closure. This article reports two immature maxillary central incisors with type I and III dens invaginatus which had necrotic pulp and a large periradicular lesion, that were treated successfully by nonsurgical root canal treatment. After apical plug placement, the remaining space was backfilled using warm vertical gutta-percha technique and the crowns were restored by composite restoration. At 6 months of follow up the patient was asymptomatic and probing depths were less than 3 mm. In addition, the reduction in the size of apical radiolucencies was observed by radiographic examinations. This case report revealed that even type III des invaginatus with an open apex and large periapical lesion, can be treated non-surgically using MTA as an apical plug. Although this case report presents a favorable result, further studies with long term follow-up periods are encouraged to support the use of nonsurgical endodontic treatment for type III dens invaginatus. PMID:29225653

In vitro biomechanical comparison of pedicle screws, sublaminar hooks, and sublaminar cables.

PubMed

Hitchon, Patrick W; Brenton, Matthew D; Black, Andrew G; From, Aaron; Harrod, Jeremy S; Barry, Christopher; Serhan, Hassan; Torner, James C

2003-07-01

Three types of posterior thoracolumbar implants are in use today: pedicle screws, sublaminar titaniumcables, and sublaminar hooks. The authors conducted a biomechanical comparison of these three implants in human cadaveric spines. Spine specimens (T5-12) were harvested, radiographically assessed for fractures or metastases, and their bone mineral density (BMD) was measured. Individual vertebrae were disarticulated and fitted with either pedicle screws, sublaminar cables, or bilateral claw hooks. The longitudinal component of each construct consisted of bilateral 10-cm rods connected with two cross-connectors. The vertebral body was embedded in cement, and the rods were affixed to a ball-and-socket apparatus for the application of a distraction force. The authors analyzed 1) 20 vertebrae implanted with screws; 2) 20 with hooks, and 3) 20 with cables. The maximum pullout (MPO) forces prior to failure (mean +/- standard deviation) for the screw, hook, and cable implants were 972 +/- 330, 802 +/- 356, and 654 +/- 248 N, respectively (p = 0.0375). Cables allowed significantly greater displacement (6.80 +/- 3.95 mm) prior to reaching the MPO force than hooks (3.73 +/- 1.42 mm) and screws (4.42 +/- 2.15 mm [p = 0.0108]). Eleven screw-implanted vertebrae failed because of screw pullout. All hook-and-cable-implanted vertebrae failed because of pedicle, middle column, or laminar fracture. These findings suggest that screws possess the greatest pullout strength of the three fixation systems. Sublaminar cables are the least rigid of the three. When screw failure occurred, the mechanism was generally screw back-out, without vertebral fractures.

Short-term outcomes of arthroscopic TightRope® fixation are better than hook plate fixation in acute unstable acromioclavicular joint dislocations.

PubMed

Bin Abd Razak, Hamid Rahmatullah; Yeo, Eng-Meng Nicholas; Yeo, William; Lie, Tijauw-Tjoen Denny

2018-07-01

The aim of this study was to compare the short-term outcomes of arthroscopic TightRope ® fixation with that of hook plate fixation in patients with acute unstable acromioclavicular joint dislocations. We conducted a prospective case-control study of twenty-six patients with an acute ACJ dislocation who underwent surgical repair with either an arthroscopic TightRope ® fixation or a hook plate from 2013 to 2016. Clinical and radiological data were collected prospectively. Clinical outcomes were evaluated using the Constant Score, the University of California at Los Angeles (UCLA) Shoulder Score, Oxford Shoulder Score as well as the visual analogue scale. Radiological outcomes were assessed with the coracoclavicular distance (CCD). Sixteen patients underwent arthroscopic TightRope ® fixation, while 10 patients underwent hook plate fixation. There were no significant differences in the preoperative variables except for the mean UCLA 4b infraspinatus score (TightRope ® 2.8 vs. hook plate 3.8; p = 0.030). Duration of surgery was significantly longer in the TightRope ® group. At 1 year post-operatively, the TightRope ® group had a significantly better Constant Score and CCD with no complications. All patients with hook plate fixation had to undergo a second procedure for removal of implant, and 3 patients had complications. Arthroscopic TightRope ® fixation is a good option for the treatment of acute unstable ACJ dislocations. It has better short-term clinical and radiological outcomes as well as lesser complications when compared to hook plate fixation. Therapeutic, Level III.

Transfissural Route Used for Preoperative Localization of Small Pulmonary Lesions with a Short Hook Wire and Suture System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Iguchi, Toshihiro, E-mail: iguchi@ba2.so-net.ne.jp; Hiraki, Takao, E-mail: takaoh@tc4.so-net.ne.jp; Gobara, Hideo, E-mail: gobara@cc.okayama-u.ac.jp

2015-02-15

PurposeWe retrospectively evaluated the results of the transfissural route for preoperative localization with a short hook wire and suture system for video-assisted thoracoscopic surgery (VATS).MethodsEleven patients with 11 tumors underwent CT-guided transfissural placement of a hook wire before VATS. This route was selected for all patients, because the distance between the tumor and interlobar fissure was much shorter than the required distance traversed using the conventional approach. Complications were evaluated using the National Cancer Institute Common Terminology Criteria for Adverse Events Version 4.0.ResultsThe hook wire was successfully placed using the transfissural route in all but one case. Of these tenmore » successful placements, two tumors needed a second puncture for optimal placement, because the CT scan showed that the first hook wire was not properly placed in the lung. In one patient, we did not attempt replacement after the first placement was incorrect. In ten successful procedures, the mean distance traversed in the parenchyma of the unaffected lung lobe was 27.9 mm. The distance between the pleura and placed hook wire was significantly shorter than the estimated distance between the pleura and hook wire using the conventional route (mean 16.3 vs. 40.9 mm; P = 0.0002). Grade 1 adverse events occurred (11 pneumothoraxes and 4 pulmonary hemorrhages). No grade 2 or higher adverse event was observed.ConclusionsThe transfissural route used for preoperative localization before VATS is useful for selected patients because this route may allow for more limited lung parenchyma resection.« less

Rhadinorhynchus oligospinosus n. sp. (Acanthocephala, Rhadinorhynchidae) from mackerels in the Pacific Ocean off Peru and related rhadinorhynchids in the Pacific, with notes on metal analysis.

PubMed

Amin, Omar M; Heckmann, Richard A

2017-01-01

Specimens of a new species of Rhadinorhynchus Lühe, 1911 are described from the chub mackerel Scomber japonicus (Scombridae) and the Chilean Jack mackerel Trachurus murphyi (Carangidae) (possibly a subspecies of Trachurus symmetricus) from the Pacific Ocean off the Peruvian coast at the Port of Chicama, La Libertad. Specimens of Rhadinorhynchus oligospinosus n. sp. are somewhat small having 11-14 rows of alternating proboscis hooks with 20-22 hooks each with posteriormost hooks in a continuous ring. Ventral hooks are robust with prominent roots but dorsal hooks are slender and shorter with discoid roots. Trunk spines are in two zones separated by a non-spiny region. Anterior trunk spines are in 2-3 complete circles but posterior spines are only ventral and lateral, and do not extend posterior to the level of the posterior end of the proboscis receptacle in both sexes. The new species is closest to Rhadinorhynchus seriolae (Yamaguti, 1963) Golvan, 1969 found in Japanese and Australian waters, but not as close to 19 other species found in the same Pacific waters off Australia, Japan, and Vietnam. In R. seriolae, posterior trunk spines extend well past the receptacle in females, among other diagnostic differences. Proboscis hooks of the new species were analyzed for chemical elements using X-ray in conjunction with EDAX (energy-dispersive analysis for X-ray) software; sulfur had a higher concentration at the edge than the middle of cut hooks. © O.M. Amin et al., published by EDP Sciences, 2017.

The relative degree of difficulty of L2 Spanish /d, t/, trill, and tap by L1 English speakers: Auditory and acoustic methods of defining pronunciation accuracy

NASA Astrophysics Data System (ADS)

Waltmunson, Jeremy C.

2005-07-01

This study has investigated the L2 acquisition of Spanish word-medial /d, t, r, (fish hook)/, word-initial /r/, and onset cluster /(fish hook)/. Two similar experiments were designed to address the relative degree of difficulty of the word-medial contrasts, as well as the effect of word-position on /r/ and /(fish hook)/ accuracy scores. In addition, the effect of vowel height on the production of [r] and the L2 emergence of the svarabhakti vowel in onset cluster /(fish hook)/ were investigated. Participants included 34 Ll English speakers from a range of L2 Spanish levels who were recorded in multiple sessions across a 6-month or 2-month period. The criteria for assessing segment accuracy was based on auditory and acoustic features found in productions by native Spanish speakers. In order to be scored as accurate, the L2 productions had to evidence both the auditory and acoustic features found in native speaker productions. L2 participant scores for each target were normalized in order to account for the variation of features found across native speaker productions. The results showed that word-medial accuracy scores followed two significant rankings (from lowest to highest): /r <= d <= (fish hook) <= t/ and /r <= (fish hook) <= d <= t/; however, when scores for /t/ included a voice onset time criterion, only the ranking /r <= (fish hook) <= d <= t/ was significant. These results suggest that /r/ is most difficult for learners while /t/ is least difficult, although individual variation was found. Regarding /r/, there was a strong effect of word position and vowel height on accuracy scores. For productions of /(fish hook)/, there was a strong effect of syllable position on accuracy scores. Acoustic analyses of taps in onset cluster revealed that only the experienced L2 Spanish participants demonstrated svarabhakti vowel emergence with native-like performance, suggesting that its emergence occurs relatively late in L2 acquisition.

Single-port thoracoscopic sympathicotomy using a double-lumen electrocautery tube and cautery hook for primary palmar hyperhidrosis: a randomized controlled trial.

PubMed

Jin, Cheng-Hua; Liu, Kai; Yu, Kai-Zhong; Tian, Hui; Mao, Zheng-Chun; Shen, Wei-Yu

2014-08-01

The objective of this study is to assess the use of a novel, double-lumen electrocautery tube (DLET) device for ablating the sympathetic nerve chain in patients with primary palmar hyperhidrosis (PPH). Forty-six patients with severe PPH were recruited into the study between November 2010 and February 2012. All patients underwent single port, bilateral video-assisted thoracoscopic sympathicotomy. Twenty-four patients were randomized to receive sympathicotomy using a conventional 5-mm electrocautery hook (hook group) and 22 patients were randomized to the DLET group. The mean postoperative follow-up period was 8.1 months (range: 1 to 15 months). After surgery the hands of all patients became dry and warm. Mean incision size was 10.6 ± 1.0 in the hook group and 6.5 ± 0.5 mm in the DLET group (p = 0.001). The mean pain score was 1.4 ± 0.6 with hook surgery and 0.9 ± 0.6 with the DLET device (p = 0.016). The mean operative time was longer in the hook group (36.8 ± 3.4 min) than in the DLET group (30.5 ± 3.9 min; p = 0.001). There were no significant differences between the two procedures in terms of hospital stay and compensatory sweating, or patient satisfaction. Pneumothorax occurred in two (8.3%) patients in the hook group and in one (4.5%) patient in the DLET group. None of the patients required chest drainage and none developed Horner syndrome. Single-port video-assisted thoracoscopic sympathicotomy using hook or DLET procedures is effective, safe, and minimally invasive method for palmar hyperhidrosis. The DLET device allows a shorter operation time, smaller incision, better cosmetic results, less pain, and better clarity of video, making it suitable for single-port thoracoscopic sympathicotomy. Georg Thieme Verlag KG Stuttgart · New York.

Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults.

PubMed

Cope, Anwen; Francis, Nick; Wood, Fiona; Mann, Mala K; Chestnutt, Ivor G

2014-06-26

Dental pain can have a considerable detrimental effect on an individual's quality of life. Symptomatic apical periodontitis and acute apical abscess are common causes of dental pain and arise from an inflamed or necrotic dental pulp, or infection of the pulpless root canal system. Clinical guidelines recommend that the first-line treatment for teeth with symptomatic apical periodontitis or an acute apical abscess should be removal of the source of inflammation or infection by local, operative measures, and that systemic antibiotics are currently only recommended for situations where there is evidence of spreading infection (cellulitis, lymph node involvement, diffuse swelling) or systemic involvement (fever, malaise). Despite this, there is evidence that dentists continue to prescribe antibiotics for these conditions. There is concern that this could contribute to the development of antibiotic-resistant bacterial colonies both within the individual and within the community as a whole. To evaluate the effects of systemic antibiotics provided with or without surgical intervention (such as extraction, incision and drainage of a swelling or endodontic treatment), with or without analgesics, for symptomatic apical periodontitis or acute apical abscess in adults. We searched the following electronic databases: Cochrane Oral Health Group's Trials Register (to 1 October 2013); Cochrane Central Register of Controlled Trials (The Cochrane Library 2013, Issue 9); MEDLINE via OVID (1946 to 1 October 2013); EMBASE via OVID (1980 to 1 October 2013) and CINAHL via EBSCO (1980 to 1 October 2013). We searched the World Health Organization (WHO) International Trials Registry Platform and the US National Institutes of Health Trials Registry (ClinicalTrials.gov) on 1 October 2013 to identify ongoing trials. We searched for grey literature using OpenGrey (to 1 October 2013) and ZETOC Conference Proceedings (1993 to 1 October 2013). We placed no restrictions on the language or date of publication when searching the electronic databases. Randomised controlled trials of systemic antibiotics in adults with a clinical diagnosis of symptomatic apical periodontitis or acute apical abscess, with or without surgical intervention (considered in this situation to be extraction, incision and drainage or endodontic treatment) and with or without analgesics. Two review authors screened the results of the searches against inclusion criteria, extracted data and assessed risk of bias independently and in duplicate. We calculated mean differences (MD) (standardised mean difference (SMD) when different scales were reported) and 95% confidence intervals (CI) for continuous data and, where results were meta-analysed, we used a fixed-effect model as there were fewer than four studies. We contacted study authors to obtain missing information. We included two trials in this review, with 62 participants included in the analyses. Both trials were conducted in university dental schools in the USA and compared the effects of oral penicillin V potassium (penicillin VK) versus a matched placebo given in conjunction with a surgical intervention (total or partial pulpectomy) and analgesics to adults with acute apical abscess or symptomatic necrotic tooth (no signs of spreading infection or systemic involvement (fever, malaise)). We assessed one study as having a high risk of bias and the other study as having unclear risk of bias.The primary outcome variables presented were participant-reported pain and swelling (one trial also reported participant-reported percussion pain). One study reported the type and number of analgesics taken by participants. One study recorded the incidence of postoperative endodontic flare-ups (people who returned with symptoms that necessitated further treatment). Adverse effects as reported in one study were diarrhoea (one participant, placebo group) and fatigue and reduced energy postoperatively (one participant, antibiotic group). No studies reporting quality of life measurements were suitable for inclusion. Objective 1: systemic antibiotics versus placebo with surgical intervention and analgesics for symptomatic apical periodontitis or acute apical abscess. Two studies provided data for the comparison between systemic antibiotics (penicillin VK) and a matched placebo for adults with acute apical abscess or a symptomatic necrotic tooth. Participants in one study all underwent a total pulpectomy of the affected tooth while participants in the other study had their tooth treated by either partial or total pulpectomy. Participants in both trials received oral analgesics. There were no statistically significant differences in participant-reported measures of pain or swelling at any of the time points assessed within the review. The MD for pain (short ordinal numerical scale 0 to 3) was -0.03 (95% CI -0.53 to 0.47) at 24 hours; 0.32 (95% CI -0.22 to 0.86) at 48 hours and 0.08 (95% CI -0.38 to 0.54) at 72 hours. The SMD for swelling was 0.27 (95% CI -0.23 to 0.78) at 24 hours; 0.04 (95% CI -0.47 to 0.55) at 48 hours and 0.02 (95% CI -0.49 to 0.52) at 72 hours. The body of evidence was assessed as at very low quality. Objective 2: systemic antibiotics without surgical intervention for adults with symptomatic apical periodontitis or acute apical abscess. We found no studies that compared the effects of systemic antibiotics with a matched placebo delivered without a surgical intervention for symptomatic apical periodontitis or acute apical abscess in adults. There is very low quality evidence that is insufficient to determine the effects of systemic antibiotics on adults with symptomatic apical periodontitis or acute apical abscess.

Friends or foes: new insights in jasmonate and ethylene co-actions.

PubMed

Zhu, Ziqiang; Lee, Benjamin

2015-03-01

One strategy for sessile plants to adapt to their surrounding environment involves the modulation of their various internal phytohormone signaling and distributions when the plants sense environmental change. There are currently dozens of identified phytohormones in plant cells and they act in concert to regulate plant growth, development, metabolism and defense. It has been determined that phytohormones often act together to achieve certain physiological functions. Thus, the study of hormone-hormone interactions is becoming a competitive research field for deciphering the underlying regulatory mechanisms. Among phytohormones, jasmonate and ethylene present a fascinating case of synergism and antagonism. They are commonly recognized as defense hormones that act synergistically. Plants impaired in jasmonate and/or ethylene signaling are susceptible to infections by necrotrophic fungi, suggesting that these two hormones are both required for defense. Moreover, jasmonate and ethylene also act antagonistically, such as in the regulation of apical hook development and wounding responses. Here, we highlight the recent breakthroughs in the understanding of jasmonate-ethylene co-actions and point out the potential power of studying protein-protein interactions for systematically exploring signal cross-talk. © The Author 2014. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Variation of sperm head shape and tail length in a species of Australian hydromyine rodent: the spinifex hopping mouse, Notomys alexis.

PubMed

Bauer, M; Breed, W G

2006-01-01

In Australia, there are around 60 species of murid rodents that occur in the subfamily Hydromyinae, most of which produce highly complex, monomorphic, spermatozoa in which the head has an apical hook together with two ventral processes containing filamentous actin and a long tail of species-specific length. One of the few exceptions to this is the spinifex hopping mouse, Notomys alexis, whose spermatozoa have previously been shown to have pleiomorphic heads. In this study, the structural organisation of the sperm head has been investigated in more detail and the variability in length of the midpiece and total length of the sperm tail has been determined for this species. The findings confirm that pleiomorphic sperm heads are invariably present in these animals and that this variability is associated with that of the nucleus, although nuclear vacuoles were not evident. The total length of the sperm tail, as well as that of the midpiece, was also highly variable both within, as well as between, individual animals. The reason(s) for this high degree of variability in sperm morphology is not known but it may relate to a relaxation of the genetic control of sperm form owing to depressed levels of inter-male sperm competition.

Kinematics of Hooke universal joint robot wrists

NASA Technical Reports Server (NTRS)

Mckinney, William S., Jr.

1988-01-01

The singularity problem associated with wrist mechanisms commonly found on industrial manipulators can be alleviated by redesigning the wrist so that it functions as a three-axis gimbal system. This paper discussess the kinematics of gimbal robot wrists made of one and two Hooke universal joints. Derivations of the resolved rate motion control equations for the single and double Hooke universal joint wrists are presented using the three-axis gimbal system as a theoretical wrist model.

77 FR 8176 - Fisheries of the Exclusive Economic Zone Off Alaska; Reallocation of Pacific Cod in the Bering...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-14

... gear to catcher vessels less than 60 feet (18.3 meters) length overall using hook-and-line or pot gear... apportionment to catcher vessels less than 60 feet (18.3 meters(m)) length overall (LOA) using hook-and-line or... and 6,445 mt to catcher vessels less than 60 feet (18.3 m) LOA using hook-and-line or pot gear...

76 FR 54137 - Fisheries of the Exclusive Economic Zone Off Alaska; Reallocation of Pacific Cod in the Bering...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-31

... using trawl gear and catcher vessels greater than or equal to 60 feet (18.3 meters (m)) length overall (LOA) using hook-and-line gear to catcher vessels less than 60 feet (18.3 m) LOA using hook-and-line or... catcher vessels less than 60 feet (18.3 m) LOA using hook-and-line or pot gear. The 2011 Pacific cod total...

78 FR 69592 - Fisheries of the Exclusive Economic Zone Off Alaska; Reallocation of Pacific Cod in the Bering...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-20

...) LOA using hook- and-line or pot gear, American Fisheries Act (AFA) catcher/processors (C/P), Amendment 80 (A80) C/Ps, C/P vessels using pot gear, and C/P vessels using hook-and-line gear in the Bering Sea... meters) LOA using hook-and-line or pot gear, AFA C/P vessels, A80 C/P vessels, C/P vessels using pot gear...

Comparative study of fourteen alkaloids from Uncaria rhynchophylla hooks and leaves using HPLC-diode array detection-atmospheric pressure chemical ionization/MS method.

PubMed

Qu, Jialin; Gong, Tianxing; Ma, Bin; Zhang, Lin; Kano, Yoshihiro; Yuan, Dan

2012-01-01

The purpose of the study is to compare alkaloid profile of Uncaria rhynchophylla hooks and leaves. Ten oxindole alkaloids and four glycosidic indole alkaloids were identified using HPLC-diode array detection (DAD) or LC-atmospheric pressure chemical ionization (APCI)-MS method, and a HPLC-UV method for simultaneous quantification of major alkaloids was validated. The hooks are characterized by high levels of four oxindole alkaloids rhynchophylline (R), isorhynchophylline (IR), corynoxeine (C) and isocorynoxeine (IC), while the leaves contained high level of two glycosidic indole alkaloids vincoside lactam (VL) and strictosidine (S). The presented methods have proven its usefulness in chemical characterization of U. rhynchophylla hooks and leaves.

The discovery of microorganisms by Robert Hooke and Antoni Van Leeuwenhoek, fellows of the Royal Society.

PubMed

Gest, Howard

2004-05-01

The existence of microscopic organisms was discovered during the period 1665-83 by two Fellows of The Royal Society, Robert Hooke and Antoni van Leeuwenhoek. In Micrographia (1665), Hooke presented the first published depiction of a microganism, the microfungus Mucor. Later, Leeuwenhoek observed and described microscopic protozoa and bacteria. These important revelations were made possible by the ingenuity of Hooke and Leeuwenhoek in fabricating and using simple microscopes that magnified objects from about 25-fold to 250-fold. After a lapse of more than 150 years, microscopy became the backbone of our understanding of the roles of microbes in the causation of infectious diseases and the recycling of chemical elements in the biosphere.

Compact artificial hand

NASA Technical Reports Server (NTRS)

Wiker, G. A.; Mann, W. A. (Inventor)

1979-01-01

A relatively simple, compact artificial hand, is described which includes hooks pivotally mounted on first frame to move together and apart. The first frame is rotatably mounted on a second frame to enable "turning at the wrist" movement without limitation. The second frame is pivotally mounted on a third frame to permit 'flexing at the wrist' movement. A hook-driving motor is fixed to the second frame but has a shaft that drives a speed reducer on the first frame which, in turn, drives the hooks. A second motor mounted on the second frame, turns a gear on the first frame to rotate the first frame and the hooks thereon. A third motor mounted on the third frame, turns a gear on a second frame to pivot it.

Microanatomy of the cochlear hook

NASA Astrophysics Data System (ADS)

Kwan, Changyow Claire; Tan, Xiaodong; Stock, Stuart R.; Soriano, Carmen; Xiao, Xianghui; Richter, Claus-Peter

2017-09-01

Communication among humans occurs through coding and decoding of acoustic information. The inner ear or cochlea acts as a frequency analyzer and divides the acoustic signal into small frequency bands, which are processed at different sites along the cochlea. The mechano-electrical conversion is accomplished by the soft tissue structures in the cochlea. While the anatomy for most of the cochlea has been well described, a detailed description of the very high frequency and vulnerable cochlear hook region is missing. To study the cochlear hook, mice cochleae were imaged with synchrotron radiation and high-resolution reconstructions have been made from the tomographic scans. This is the first detailed description of the bony and soft tissues of the hook region of the mammalian cochlea.

Newton–Hooke-type symmetry of anisotropic oscillators

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, P.M., E-mail: zhpm@impcas.ac.cn; Horvathy, P.A., E-mail: horvathy@lmpt.univ-tours.fr; Laboratoire de Mathématiques et de Physique Théorique, Université de Tours

2013-06-15

Rotation-less Newton–Hooke-type symmetry, found recently in the Hill problem, and instrumental for explaining the center-of-mass decomposition, is generalized to an arbitrary anisotropic oscillator in the plane. Conversely, the latter system is shown, by the orbit method, to be the most general one with such a symmetry. Full Newton–Hooke symmetry is recovered in the isotropic case. Star escape from a galaxy is studied as an application. -- Highlights: ► Rotation-less Newton–Hooke (NH) symmetry is generalized to an arbitrary anisotropic oscillator. ► The orbit method is used to find the most general case for rotation-less NH symmetry. ► The NH symmetry ismore » decomposed into Heisenberg algebras based on chiral decomposition.« less

Desiccation Treatment and Endogenous IAA Levels Are Key Factors Influencing High Frequency Somatic Embryogenesis in Cunninghamia lanceolata (Lamb.) Hook

PubMed Central

Zhou, Xiaohong; Zheng, Renhua; Liu, Guangxin; Xu, Yang; Zhou, Yanwei; Laux, Thomas; Zhen, Yan; Harding, Scott A.; Shi, Jisen; Chen, Jinhui

2017-01-01

Cunninghamia lanceolata (Lamb.) Hook (Chinese fir) is an important tree, commercially and ecologically, in southern China. The traditional regenerating methods are based on organogenesis and cutting propagation. Here, we report the development of a high-frequency somatic embryogenesis (SE) regeneration system synchronized via a liquid culture from immature zygotic embryos. Following synchronization, PEM II cell aggregates were developmentally equivalent in appearance to cleaved zygotic embryos. Embryo and suspensor growth and subsequent occurrence of the apical and then the cotyledonary meristems were similar for zygotic and SE embryo development. However, SE proembryos exhibited a more reddish coloration than zygotic proembryos, and SE embryos were smaller than zygotic embryos. Mature somatic embryos gave rise to plantlets on hormone-free medium. For juvenile explants, low concentrations of endogenous indole-3-acetic acid in initial explants correlated with improved proembryogenic mass formation, and high SE competency. Analysis of karyotypes and microsatellites detected no major genetic variation in the plants regenerated via SE, and suggest a potential in the further development of this system as a reliable methodology for true-to-type seedling production. Treatment with polyethylene glycol (PEG) and abscisic acid (ABA) were of great importance to proembryo formation and complemented each other. ABA assisted the growth of embryonal masses, whereas PEG facilitated the organization of the proembryo-like structures. SOMATIC EMBRYOGENESIS RECEPTOR KINASE SERK) and the WUSCHEL homeobox (WOX) transcription factor served as molecular markers during early embryogenesis. Our results show that ClSERKs are conserved and redundantly expressed during SE. SERK and WOX transcript levels were highest during development of the proembryos and lowest in developed embryos. ClWOX13 expression correlates with the critical transition from proembryogenic masses to proembryos. Both SERK and WOX expression reveal their applicability in Chinese fir as markers of early embryogenesis. Overall, the findings provided evidence for the potential of this system in high fidelity Chinese fir seedlings production. Also, SE modification strategies were demonstrated and could be applied in other conifer species on the basis of our hormonal, morphological and molecular analyses. PMID:29259612

Tolerance of brightness and contrast adjustments on chronic apical abscess and apical granuloma interpretation

NASA Astrophysics Data System (ADS)

Purnamasari, L.; Iskandar, H. H. B.; Makes, B. N.

2017-08-01

In digitized radiography techniques, adjusting the image enhancement can improve the subjective image quality by optimizing the brightness and contrast for diagnostic needs. To determine the value range of image enhancement (brightness and contrast) on chronic apical abscess and apical granuloma interpretation. 30 periapical radiographs that diagnosed chronic apical abscess and 30 that diagnosed apical granuloma were adjusted by changing brightness and contrast values. The value range of brightness and contrast adjustment that can be tolerated in radiographic interpretations of chronic apical abscess and apical granuloma spans from -10 to +10. Brightness and contrast adjustments on digital radiographs do not affect the radiographic interpretation of chronic apical abscess and apical granuloma if conducted within the value range.

76 FR 77375 - Airworthiness Directives; Apical Industries, Inc., (Apical) Emergency Float Kits

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-13

... Airworthiness Directives; Apical Industries, Inc., (Apical) Emergency Float Kits AGENCY: Federal Aviation... the Apical emergency float kits installed on certain model helicopters under supplemental type... the service information identified in this AD from Apical Industries, Inc., 2608 Temple Heights Drive...

In vivo analysis of acromioclavicular joint motion after hook plate fixation using three-dimensional computed tomography.

PubMed

Kim, Yoon Sang; Yoo, Yon-Sik; Jang, Seong Wook; Nair, Ayyappan Vijayachandran; Jin, Hyonki; Song, Hyun-Seok

2015-07-01

The clavicle hook plate can be used to treat acromioclavicular and coracoclavicular ligament injury or distal clavicular fracture with comminution. However, the hook plate can induce subacromial impingement, resulting in discomfort from the hardware. Our inclusion criteria were (1) men and women aged older than 20 years and (2) the presence of comminuted distal clavicular fractures (Neer type IIB) fixed with a hook plate (Synthes, Oberdorf, Switzerland). Three-dimensional computed tomography was obtained before removal of the hook plate. Seven patients were enrolled prospectively. The mean age was 42 years (range, 24-60 years). Zero degree images and abduction images were obtained. The sagittal cut surface was obtained 5 mm medial from the distal clavicle. The equator of the cut surface of the clavicle was compared with the full abduction model to analyze rotation. The center of the cut surface of the clavicle was compared with the full abduction model to analyze translation. The average difference in rotation of the distal clavicle between both shoulders was 16° (range, 3°-22°; P = .001). The mean difference in anterior translation of the distal clavicle was 2.2 mm (range, -0.7 to 5.6 mm; P = .030). Hook plate fixation at the acromioclavicular joint causes decreased internal rotation and increased anterior translation of the distal clavicle with respect to the medial acromion, indicating that the scapula relative to the thorax has decreased posterior tilting and increased external rotation in shoulders fixed using a hook plate. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

New Caledonian crows attend to multiple functional properties of complex tools

PubMed Central

St Clair, James J. H.; Rutz, Christian

2013-01-01

The ability to attend to the functional properties of foraging tools should affect energy-intake rates, fitness components and ultimately the evolutionary dynamics of tool-related behaviour. New Caledonian crows Corvus moneduloides use three distinct tool types for extractive foraging: non-hooked stick tools, hooked stick tools and tools cut from the barbed edges of Pandanus spp. leaves. The latter two types exhibit clear functional polarity, because of (respectively) a single terminal, crow-manufactured hook and natural barbs running along one edge of the leaf strip; in each case, the ‘hooks’ can only aid prey capture if the tool is oriented correctly by the crow during deployment. A previous experimental study of New Caledonian crows found that subjects paid little attention to the barbs of supplied (wide) pandanus tools, resulting in non-functional tool orientation during foraging. This result is puzzling, given the presumed fitness benefits of consistently orienting tools functionally in the wild. We investigated whether the lack of discrimination with respect to (wide) pandanus tool orientation also applies to hooked stick tools. We experimentally provided subjects with naturalistic replica tools in a range of orientations and found that all subjects used these tools correctly, regardless of how they had been presented. In a companion experiment, we explored the extent to which normally co-occurring tool features (terminal hook, curvature of the tool shaft and stripped bark at the hooked end) inform tool-orientation decisions, by forcing birds to deploy ‘unnatural’ tools, which exhibited these traits at opposite ends. Our subjects attended to at least two of the three tool features, although, as expected, the location of the hook was of paramount importance. We discuss these results in the context of earlier research and propose avenues for future work. PMID:24101625

Five new species of Pedibothrium (Tetraphyllidea: Onchobothriidae) from the tawny nurse shark, Nebrius ferrugineus, in the Pacific Ocean.

PubMed

Caira, J N; Tracy, Randall; Euzet, L

2004-04-01

The spiral intestines of 7 Tawny nurse sharks (Nebrius ferrugineus; Rhincodontidae) from Australia and French Polynesia were examined for tapeworms. These sharks hosted 5 new species of Pedibothrium. The 5 species were prepared for light and scanning electron microscopy. Whereas 3 of the species exhibit the bipronged hooks typical of members of Pedibothrium, 1 species was found to possess tiny unipronged hooks or to lack some, or all, hooks, and all individuals of the fifth species appeared to lack bothridial hooks entirely. Nonetheless, the otherwise remarkable similarities between these species and the species of Pedibothrium bearing bipronged hooks were considered to be sufficient to justify the placement of these 2 species in this genus. All 5 species possess proglottid features typical of Pedibothrium, including a uterus that extends anteriorly only to the level of the cirrus sac and a cirrus sac that is bent anteriorly and is crossed by the vagina. All 5 species also exhibit uniloculated bothridia. Of particular note was the fact that all 5 species exhibit bladelike spinitrichs with elongated distal tips, a form of microthrix currently known only from species of Pedibothrium. As a consequence, these species were treated as possessing modified hooks or as having lost hooks. The diagnoses of Pedibothrium and Onchobothriidae were emended to include these species. Each of the 5 new species bears a strong resemblance to 1 or more species of Pedibothrium hosted by a species of rhincodontid shark other than N. ferrugineus. Much of Southwell's type and voucher material of Pedibothrium was located and used to verify the identity of Pedibothrium kerkhami and many of the hosts from which Southwell's material of Pedibothrium was collected. This material suggests that P. kerkhami parasitizes Stegostoma fasciatum and not N. ferrugineus.

Comparison of the intrusion effects on the maxillary incisors between implant anchorage and J-hook headgear.

PubMed

Deguchi, Toru; Murakami, Takashi; Kuroda, Shingo; Yabuuchi, Toshinori; Kamioka, Hiroshi; Takano-Yamamoto, Teruko

2008-05-01

Recently, miniscrews have been used to provide anchorage during orthodontic treatment, especially for incisor intrusion. Miniscrews during incisor intrusion are commonly used in implant orthodontics. Traditionally, effective incisor intrusion has been accomplished with J-hook headgear. In this study, we compared the effect of incisor intrusion, force vector, and amount of root resorption between implant orthodontics and J-hook headgear. Lateral cephalometric radiographs from 8 patients in the implant group and 10 patients in the J-hook headgear group were analyzed for incisor retraction. The estimated force vector was analyzed in the horizontal and vertical directions in both groups. Root resorption was also measured on periapical radiographs. In the implant group, significant reductions in overjet, overbite, maxillary incisor to palatal plane, and maxillary incisor to upper lip were observed after intrusion of the incisors. In the J-hook headgear group, significant reductions in overjet, overbite, maxillary incisor to upper lip, and maxillary incisor to SN plane were observed after intrusion of the incisors. There were significantly greater reductions in overbite, maxillary incisor to palatal plane, and maxillary incisor to upper lip in the implant group than in the J-hook headgear group. Estimated force analysis resulted in significantly more force in the vertical direction and less in the horizontal direction in the implant group. Furthermore, significantly less root resorption was observed in the implant group compared with the J-hook headgear group. The maxillary incisors were effectively intruded by using miniscrews as orthodontic anchorage without patient cooperation. The amount of root resorption was not affected by activating the ligature wire from the miniscrew during incisor intrusion.

The HOOK region of voltage-gated Ca2+ channel β subunits senses and transmits PIP2 signals to the gate.

PubMed

Park, Cheon-Gyu; Park, Yongsoo; Suh, Byung-Chang

2017-02-01

The β subunit of voltage-gated Ca 2+ (Ca V ) channels plays an important role in regulating gating of the α1 pore-forming subunit and its regulation by phosphatidylinositol 4,5-bisphosphate (PIP 2 ). Subcellular localization of the Ca V β subunit is critical for this effect; N-terminal-dependent membrane targeting of the β subunit slows inactivation and decreases PIP 2 sensitivity. Here, we provide evidence that the HOOK region of the β subunit plays an important role in the regulation of Ca V biophysics. Based on amino acid composition, we broadly divide the HOOK region into three domains: S (polyserine), A (polyacidic), and B (polybasic). We show that a β subunit containing only its A domain in the HOOK region increases inactivation kinetics and channel inhibition by PIP 2 depletion, whereas a β subunit with only a B domain decreases these responses. When both the A and B domains are deleted, or when the entire HOOK region is deleted, the responses are elevated. Using a peptide-to-liposome binding assay and confocal microscopy, we find that the B domain of the HOOK region directly interacts with anionic phospholipids via polybasic and two hydrophobic Phe residues. The β2c-short subunit, which lacks an A domain and contains fewer basic amino acids and no Phe residues in the B domain, neither associates with phospholipids nor affects channel gating dynamically. Together, our data suggest that the flexible HOOK region of the β subunit acts as an important regulator of Ca V channel gating via dynamic electrostatic and hydrophobic interaction with the plasma membrane. © 2017 Park et al.

Performance Outcomes After Hook of Hamate Fractures in Major League Baseball Players.

PubMed

Guss, Michael S; Begly, John P; Ramme, Austin J; Taormina, David P; Rettig, Michael E; Capo, John T

2017-07-17

Major League Baseball (MLB) players are at risk of hook of hamate fractures. There is a paucity of data assessing the effect of a hook of hamate fracture on MLB players' future athletic performance. To determine if MLB players who sustain hook of hamate fractures demonstrate decreased performance upon return to competition when compared with their performance before injury and that of their control-matched peers. Retrospective Case-Control Design. Retrospective Database Study. 18 MLB players who sustained hook of hamate fractures. Data for 18 MLB players with hook of hamate fractures incurred over 26 seasons (1989 to 2014) were obtained from injury reports, press releases, and player profiles ( www.mlb.com and www.baseballreference.com ). Player age, position, number of years in the league, mechanism of injury and treatment were recorded. Individual season statistics for the two seasons immediately prior to injury and the two seasons after injury for the main performance variable - wins above replacement (WAR) were obtained. Eighteen controls matched by player position, age, and performance statistics were identified. A performance comparison of the cohorts was performed. Post-injury performance compared to pre-injury performance and matched-controls. Mean age at the time of injury was 25.1 years with a mean of 4.4 seasons of MLB experience prior to injury. All injuries were sustained to their nondominant batting hand. All players underwent operative intervention. There was no significant change in WAR or ISO when pre-injury and post-injury performance was compared. When compared with matched-controls, no significant decline in performance in WAR the first season and second season after injury was found. MLB players sustaining hook of hamate fractures can reasonably expect to return to their pre-injury performance levels following operative treatment.

Neoandracantha peruensis n. gen. n. sp. (Acanthocephala, Polymorphidae) described from cystacanths infecting the ghost crab Ocypode gaudichaudii on the Peruvian coast

PubMed Central

2017-01-01

The cystacanths of Neoandracantha peruensis n. gen. n. sp. are described from the ghost crab Ocypode gaudichaudii collected from the Pacific coast of Peru. While it is uncommon to describe acanthocephalan taxa from immature stages, the presence of clear-cut distinguishing features separating the present material from its nearest congeneric taxa, and the absence of adults, justifies the erection N. peruensis. The new genus is distinguished by having three separate fields of trunk spines. Specimens of N. peruensis have a slender trunk with two anterior swellings, 3 separate fields of spines on the foretrunk swelling, and no genital spines on the hindtrunk. The proboscis of the new species is heavily armored with 21–22 longitudinal rows of 22 hooks each. Hook no. 14 is more robust ventrally than dorsally. Cystacanths of N. peruensis also have a long tubular hindtrunk and the males have diagonal testes in the midtrunk swelling. Specimens of the closely related Andracantha Schmidt, 1975 have anteriorly enlarged pear-shaped Corynosoma-like trunks, only two fields of anterior trunk spines with occasional genital spines, and bilateral or tandem testes. Proboscides of species of Andracantha have considerably fewer hooks that gradually decrease in size posteriorly. The taxonomic component of this work is amplified by metal analysis of hooks and spines that shows a marked amount of magnesium (Mg) in hooks but not in spines. The highest level of sulfur (S) was found in the outer layer of hooks and anterior spines. The metal footprint of hooks and spines varies in different species of acanthocephalans and has an interspecific diagnostic value. PMID:29072573

Reproducibility of Echocardiograph-Derived Multilevel Left Ventricular Apical Twist Mechanics.

PubMed

Stewart, Glenn M; Yamada, Akira; Kavanagh, Justin J; Haseler, Luke J; Chan, Jonathan; Sabapathy, Surendran

2016-02-01

Left ventricular (LV) twist mechanics are routinely assessed via echocardiography in clinical and research trials investigating the function of obliquely oriented myocardial fibers. However, echocardiograph-derived measures of LV twist may be compromised by nonstandardized acquisition of the apical image. This study examined the reproducibility of echocardiograph-derived parameters of apical twist mechanics at multiple levels of the apical myocardium. Two sets of 2D LV parasternal short-axis images were obtained in 30 healthy subjects (24 men; 19-57 year) via echocardiography. Images were acquired immediately distal to the papillary muscles (apical image 1), immediately above the point of LV cavity obliteration at end systole (apical image 3), and midway between apical image 1 and apical image 3 (apical image 2). Repeat scans were performed within 1 hour, and twist mechanics (rotation and rotation rate) were calculated via frame-by-frame tracking of natural acoustic echocardiographic markers (speckle tracking). The magnitude of apical rotation increased progressively toward the apex (apical image 1: 4.2 ± 2.1°, apical image 2: 7.2 ± 3.9°, apical image 3: 11.8 ± 4.6°). apical images 1, 2, and 3 each had moderate to good correlations between repeat scans (ICC: 0.531-0.856). When apical images 1, 2, and 3 were averaged, rotation was 7.7 ± 2.7° and between-scan correlation was excellent (ICC: 0.910). Similar results were observed for systolic and diastolic rotation rates. Averaging multiple standardized apical images, tending progressively toward the apex, generated the most reproducible rotation indices and may be optimal for the assessment of LV twist mechanics across therapeutic, interventional, and research studies; however, care should be taken given the influence of acquisition level on the magnitude of apical rotation. © 2015, Wiley Periodicals, Inc.

Establishing Apical Patency: To be or not to be?

PubMed

Mohammadi, Zahed; Jafarzadeh, Hamid; Shalavi, Sousan; Kinoshita, Jun-Ichiro

2017-04-01

The apical portion of the root canal is very complex and challenging during endodontic treatment. Root canal preparation and obturation to the apical constriction may provide the best prognosis. Incomplete debridement, foramen transportation, and inadequate seal in the apical portion are considered to be responsible for treatment failure. The technique "apical patency" is considered as a way for maintaining the apical part the free of the debris by recapitulation, using a small K-file through the area of the apical foramen. This term was firstly proposed by Buchanan. In this technique, the smallest diameter file is set 1 mm longer than working length and recapitulated after each instrument to prevent packing of debris in the apical part. Apical patency has been found to be effective in achieving an apical seal with gutta-percha. Teeth prepared with a step back method and with maintained apical patency may show less leakage when obturated with cold lateral condensation technique. Data regarding the effect of apical patency on the healing of periapical tissue are very scarce, and it has been shown that the patency file has detrimental effect on the healing of periapical tissues in animal studies. However, using patency file in endodontic treatment is controversial and further studies are needed. The purpose of this article is to review the effect of using a patency file on the extrusion of root canal contents, the apical seal, postoperative pain, and healing of periapical tissues. Furthermore, the effect of establishing patency on reaching irrigation solutions to the apical portion of the canal and prognosis of root canal treatment are discussed. Keywords: Apical patency, Apical seal, Apical transportation, Postoperative pain, Prognosis.

Photocopy of plan (in collection of U.S. Coast Guard Civil ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Photocopy of plan (in collection of U.S. Coast Guard Civil Engineering Unit Providence, Warwick, RI), U.S. Coast Guard Civil Engineering, third district, Sandy Hook L/B Station, Sandy Hook N.J., buoy hoist installation and bldg alterations, January 3, 1952 Details of 4 ton hoist and building, wharf B - U.S. Coast Guard Sandy Hook Station, Western Docking Structure, West of intersection of Canfield Road & Hartshorne Drive, Highlands, Monmouth County, NJ

Photocopy of plan (in U.S. Army office of Army Engineers ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Photocopy of plan (in U.S. Army office of Army Engineers plans and drawings, Fort Hancock and Sandy hook proving ground, record group 7, drawer 44, Cartographic and Architectural branc, The National Archives, Washington, DC) , Ordnance Dept. U.S. Army, proposed addition to dock at Sandy Hook, 1918 Ordnance wharf and boathouse - U.S. Coast Guard Sandy Hook Station, Western Docking Structure, West of intersection of Canfield Road & Hartshorne Drive, Highlands, Monmouth County, NJ

50 CFR 679.20 - General limitations.

Code of Federal Regulations, 2012 CFR

2012-10-01

... season (1) Trawl 60% 20% 20% (i) Trawl CV 70% 10% 20% (ii) Trawl CP 50% 30% 20% (2) Hook-and-line CP and...-line CP 48.7 (5) Pot CV ≥60 ft (18.3 m) LOA 8.4 (6) Pot CP 1.5 (7) AFA trawl CP 2.3 (8) Amendment 80...) Trawl CV 74 % 11 % 15 % (ii) Trawl CP 75 % 25 % 0 % (2) Hook-and-line CP, hook-and-line CV ≥60 ft (18.3...

50 CFR 679.20 - General limitations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... season (1) Trawl 60% 20% 20% (i) Trawl CV 70% 10% 20% (ii) Trawl CP 50% 30% 20% (2) Hook-and-line CP and...-line CP 48.7 (5) Pot CV ≥60 ft (18.3 m) LOA 8.4 (6) Pot CP 1.5 (7) AFA trawl CP 2.3 (8) Amendment 80...) Trawl CV 74 % 11 % 15 % (ii) Trawl CP 75 % 25 % 0 % (2) Hook-and-line CP, hook-and-line CV ≥60 ft (18.3...

Stainless hooks to bond lower lingual retainer.

PubMed

Durgekar, Sujala G; Nagaraj, K

2011-01-01

We introduced a simple and economical technique for precise placement of lower lingual retainers. Two stainless steel hooks made of 0.6mm wire are placed interdentally in the embrasure area between canine and lateral incisor bilaterally to lock the retainer wire in the correct position. Etch, rinse and dry the enamel surfaces with the retainer passively in place, then bond the retainer with light-cured adhesive. Hooks are simple to fabricate and eliminate the need for a transfer tray.

The Effects of Biomechanical Factors to Teach Different Hook Punch Techniques in Boxing and Education Strategies

ERIC Educational Resources Information Center

Bingul, Bergun Meric; Bulgun, Cigdem; Tore, Ozlem; Bal, Erdal; Aydin, Mensure

2018-01-01

The aim of this study was to investigate the effects of biomechanic factors to teach different hook punches in boxing. Eight light middleweight boxing athletes (mean age ± SD 19.00 ± 2.00 yrs, mean height ± SD 173.88 ± 3.89 cm, mean weight ± SD 64.25 ± 4.66 kg) participated in this study. Athletes performed a trial using three different hook punch…

Meanest foundations and nobler superstructures: Hooke, Newton and the "compounding of the celestiall motions of the planets

NASA Astrophysics Data System (ADS)

Gal, Ofer

This book is a historical-epistemological study of one the most consequential idea of early modern celestial mechanics: Robert Hooke's proposal to "compoun[d] the celestial motions of the planets of a direct motion by the tangent & an attractive motion towards a central body," a proposal which Isaac Newton adopted and realized in his Principia. Hooke's Programme was revolutionary both cosmologically and mathematically. It presented "the celestial motions," the proverbial symbol of stability and immutability, as a process of continuous change, and prescribed only parameters of rectilinear motions and rectilinear attractions for calculating their closed curved orbits. Yet the traces of Hooke's construction of his Programme for the heavens lead through his investigations in such earthly disciplines as microscopy, practical optics and horology, and the mathematical tools developed by Newton to accomplish it appear no less local and goal-oriented than Hooke's lenses and springs. This transgression of the boundaries between the theoretical, experimental and technological realms is reminiscent of Hooke's own free excursions in and out of the circles occupied by gentlemen-philosophers, university mathematicians, instrument makers, technicians and servants. It presents an opportunity to examine the social and epistemological distinctions, relations and hierarchies between those realms and their inhabitants, and compels a critical assessment of the philosophical categories they embody.

Effects of Ag+ on ion transport by the corneal epithelium of the rabbit.

PubMed

Klyce, S D; Marshall, W S

1982-01-01

Exposure of the in vitro rabbit corneal epithelium to Ag+ by the addition of AgNO3 (10(-7)-10(-5) M) to the apical surface or by the use of imperfectly chlorided Ag/AgCl half-cells in Ussing-style membrane chambers, greatly increases short-circuit current and transepithelial potential. The early phase (the first 30 min) of the short-circuit current stimulation by Ag+ is linearly dependent on tear-side sodium concentration, is largely a result of a tenfold increase in net Na+ uptake and is incompletely inhibited by ouabain, suggesting that Ag+ increases cation (primarily Na+) conductance of the apical membrane. This mechanism for the Ag+ effect is supported by microelectrode experiments, wherein Ag+ depolarizes specifically the apical barrier potential and increases apical barrier conductance. A later phase in the effect (0.5-3 hr) is characterized by a gradual increase in 36Cl- and 14C-mannitol unidirectional fluxes, by a decline in epithelial resting potential and short-circuit current, by complete ouabain inhibition and by fit to saturation kinetics with respect to Na+ concentration in the bathing media. This phase of the effect apparently reflects a nonselective opening of the paracellular pathway in the epithelium and is rate-limited by Na+ pump activity at the basolateral membrane. Both phases are associated with swelling of the corneal stroma and may be rapidly reversed using thiol agents (reduced glutathione and dithiothreitol). The results suggest that Ag+ may be useful in the study of cation transport by epithelia and the work provides basic physiological information that is pertinent to the prophylactic use of AgNO3 in clinical ophthalmology.

Melanocortin 3 Receptor Has a 5′ Exon That Directs Translation of Apically Localized Protein From the Second In-Frame ATG

PubMed Central

Park, Jeenah; Sharma, Neeraj

2014-01-01

Melanocortin-3 receptor (MC3R) is a canonical MSH receptor that plays an essential role in energy homeostasis. Variants in MC3R have been implicated in obesity in humans and mice. However, interpretation of the functional consequences of these variants is challenging because the translational start site of MC3R is unclear. Using 5′ rapid amplification of cDNA ends, we discovered a novel upstream exon that extends the length of the 5′ untranslated region (UTR) in MC3R without changing the open-reading frame. The full-length 5′ UTR directs utilization of an evolutionarily conserved second in-frame ATG as the primary translation start site. MC3R synthesized from the second ATG is localized to apical membranes of polarized Madin-Darby canine kidney cells, consistent with its function as a cell surface mediator of melanocortin signaling. Expression of MC3R causes relocalization of melanocortin receptor accessory protein 2, an accessory factor for melanocortin-2 receptor, to the apical membrane, coincident with the location of MC3R. In contrast, protein synthesized from MC3R cDNAs lacking the 5′ UTR displayed diffuse cytosolic distribution and has no effect on the distribution of melanocortin receptor accessory protein 2. Our findings demonstrate that a previously unannotated 5′ exon directs translation of MC3R protein that localizes to apical membranes of polarized cells. Together, our work provides insight on the structure of human MC3R and reveals a new pathway for regulation of energy metabolism. PMID:25051171

Fishing-gear restrictions and biomass gains for coral reef fishes in marine protected areas.

PubMed

Campbell, Stuart J; Edgar, Graham J; Stuart-Smith, Rick D; Soler, German; Bates, Amanda E

2018-04-01

Considerable empirical evidence supports recovery of reef fish populations with fishery closures. In countries where full exclusion of people from fishing may be perceived as inequitable, fishing-gear restrictions on nonselective and destructive gears may offer socially relevant management alternatives to build recovery of fish biomass. Even so, few researchers have statistically compared the responses of tropical reef fisheries to alternative management strategies. We tested for the effects of fishery closures and fishing gear restrictions on tropical reef fish biomass at the community and family level. We conducted 1,396 underwater surveys at 617 unique sites across a spatial hierarchy within 22 global marine ecoregions that represented 5 realms. We compared total biomass across local fish assemblages and among 20 families of reef fishes inside marine protected areas (MPAs) with different fishing restrictions: no-take, hook-and-line fishing only, several fishing gears allowed, and sites open to all fishing gears. We included a further category representing remote sites, where fishing pressure is low. As expected, full fishery closures, (i.e., no-take zones) most benefited community- and family-level fish biomass in comparison with restrictions on fishing gears and openly fished sites. Although biomass responses to fishery closures were highly variable across families, some fishery targets (e.g., Carcharhinidae and Lutjanidae) responded positively to multiple restrictions on fishing gears (i.e., where gears other than hook and line were not permitted). Remoteness also positively affected the response of community-level fish biomass and many fish families. Our findings provide strong support for the role of fishing restrictions in building recovery of fish biomass and indicate important interactions among fishing-gear types that affect biomass of a diverse set of reef fish families. © 2017 Society for Conservation Biology.

KENNEDY SPACE CENTER, FLA. - This bird's-eye view of a high bay in the Orbiter Processing Facility (OPF) shows the open payload bay of Space Shuttle Discovery surrounded by the standard platforms and equipment required to process a Space Shuttle orbiter. The high bay is 197 feet (60 meters) long, 150 feet (46 meters) wide, 95 feet (29 meters) high, and encompasses a 29,000-square-foot (2,694-meter) area. The 30-ton (27-metric-ton) bridge crane (yellow device, right) has a hook height of approximately 66 feet (20 meters). Platforms, a main access bridge, and two rolling bridges with trucks provide access to various parts of the orbiter. In addition to routine servicing and checkout, the inspections and modifications made to enhance Discovery's performance and upgrade its systems were performed in the OPF during its recently completed Orbiter Major Modification (OMM) period.

NASA Image and Video Library

2003-09-02

KENNEDY SPACE CENTER, FLA. - This bird's-eye view of a high bay in the Orbiter Processing Facility (OPF) shows the open payload bay of Space Shuttle Discovery surrounded by the standard platforms and equipment required to process a Space Shuttle orbiter. The high bay is 197 feet (60 meters) long, 150 feet (46 meters) wide, 95 feet (29 meters) high, and encompasses a 29,000-square-foot (2,694-meter) area. The 30-ton (27-metric-ton) bridge crane (yellow device, right) has a hook height of approximately 66 feet (20 meters). Platforms, a main access bridge, and two rolling bridges with trucks provide access to various parts of the orbiter. In addition to routine servicing and checkout, the inspections and modifications made to enhance Discovery's performance and upgrade its systems were performed in the OPF during its recently completed Orbiter Major Modification (OMM) period.

A double standard for "Hooking Up": How far have we come toward gender equality?

PubMed

Allison, Rachel; Risman, Barbara J

2013-09-01

While sexual attitudes have liberalized in the past half century, research is mixed as to whether attitudes have become less gendered over time. Recent studies on college students' sexual and romantic relationships suggest that a sexual double standard continues to organize sexuality on many campuses. Data from the Online College Social Life Survey shed light on students' evaluation of casual sex, or "hooking up." In addition to exploring gendered attitudinal patterns, we use gender structure theory to explore how individual characteristics and normative expectations of campus group affiliations shape attitudes. While three quarters of students do not hold different standards for men and women's hooking up, attitudes are more conservative than liberal, with almost half of students losing respect for men and women who hook up "a lot." However, men are more likely to hold a traditional double standard, while women are more likely to espouse egalitarian conservative attitudes. Individual characteristics, including age, religion, race, social class and sexual orientation are frequently related to sexual attitudes, as are number of hook ups, fraternity/sorority affiliation and varsity athletic participation. Published by Elsevier Inc.

Devil's Claw

MedlinePlus

... is an herb. The botanical name, Harpagophytum, means "hook plant" in Greek. This plant gets its name ... appearance of its fruit, which is covered with hooks meant to attach onto animals in order to ...

Crafting the microworld: how Robert Hooke constructed knowledge about small things

PubMed Central

Lawson, Ian

2016-01-01

This paper investigates the way in which Robert Hooke constructed his microscopical observations. His Micrographia is justifiably famous for its detailed engravings, which communicated Hooke's observations of tiny nature to his readers, but less attention has been paid to how he went about making the observations themselves. In this paper I explore the relationship between the materiality of his instrument and the epistemic images he produced. Behind the pictures lies an array of hidden materials, and the craft knowledge it took to manipulate them. By investigating the often counter-theoretical and conflicting practices of his ingenious microscope use, I demonstrate the way in which Hooke crafted the microworld for his readers, giving insight into how early modern microscopy was understood by its practitioners and audience. PMID:27017680

Robert Hooke, 1635-1703.

PubMed

Rowbury, Robin

2012-01-01

Robert Hooke was a polymath whose expertise during the 17th century spanned many different scientific areas. As a schoolboy on the Isle of Wight he was obsessed with the possibility of human flight and later became equally absorbed in cosmology and planetary motion. His skills as an artist were put to good use both as an architect following the Great Fire of London and before that in Micrographia. Although that book is best known for demonstrating the power of Hooke's microscope, Micrographia describes distant planetary bodies, the wave theory of light, the organic origin of fossils, and various other philosophical and scientific interests of its author The following thumbnail sketches of Hooke reveal him to be a man of enormous energy and imagination whose ideas were often pirated or under-rated.

CRAFTING THE MICROWORLD: HOW ROBERT HOOKE CONSTRUCTED KNOWLEDGE ABOUT SMALL THINGS.

PubMed

Lawson, Ian

2016-03-20

This paper investigates the way in which Robert Hooke constructed his microscopical observations. His Micrographia is justifiably famous for its detailed engravings, which communicated Hooke's observations of tiny nature to his readers, but less attention has been paid to how he went about making the observations themselves. In this paper I explore the relationship between the materiality of his instrument and the epistemic images he produced. Behind the pictures lies an array of hidden materials, and the craft knowledge it took to manipulate them. By investigating the often counter-theoretical and conflicting practices of his ingenious microscope use, I demonstrate the way in which Hooke crafted the microworld for his readers, giving insight into how early modern microscopy was understood by its practitioners and audience.

Physiological response to hooking stress in hatchery and wild rainbow trout (Salmo gairdneri)

USGS Publications Warehouse

Wydoski, R.S.; Wedemeyer, G.A.; Nelson, N. C.

1976-01-01

This study evaluated the physiological response of rainbow trout to hooking stress after being played under standardized conditions (0–5 min) and estimated the time needed for recovery (to 72 h). Plasma osmolality and chloride measurements were used to evaluate osmoregulatory disturbances and gill ion-exchange function, and plasma glucose was used as an index of the generalized nonspecific physiological stress response. Hooking stress caused more severe blood chemistry differences in hatchery fish than in wild trout. Also, hooking stress imposed a greater stress on larger than on smaller hatchery rainbow trout. Higher water temperatures aggravated the delayed hyperglycemia and hyperchloremia in both hatchery and wild trout but only about 3 days were needed for recovery at 4, 10, or 20 C.

External tissue expansion for difficult wounds using a simple cost effective technique.

PubMed

Nandhagopal, Vijayaraghavan; Chittoria, Ravi Kumar; Mohapatra, Devi Prasad; Thiruvoth, Friji Meethale; Sivakumar, Dinesh Kumar; Ashokan, Arjun

2015-01-01

To study and discuss role of external tissue expansion and wound closure (ETEWC) technique using hooks and rubber bands. The present study is a retrospective analysis of nine cases of wounds of different aetiology where ETEWC technique was applied using hooks and rubber bands. All the wounds in the study healed completely without split thickness skin graft (SSG) or flap. ETEWC technique using hooks and rubber bands is a cost-effective technique which can be used for wound closure without SSG or flap.

Photocopy of plan (in U.S. Army office of Army Engineers ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Photocopy of plan (in U.S. Army office of Army Engineers plans and drawings, Fort Hancock and Sandy hook proving ground, record group 7, drawer 44, Cartographic and Architectural branc, The National Archives, Washington, DC) Gillespie, G.L., map of a portion of Sandy Hook, NJ showing condition of beach in vicinity of dynamite gun emplacements, 1894 Engineer's wharf - U.S. Coast Guard Sandy Hook Station, Western Docking Structure, West of intersection of Canfield Road & Hartshorne Drive, Highlands, Monmouth County, NJ

Photocopy of plan (in U.S. Army office of Army Engineers ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Photocopy of plan (in U.S. Army office of Army Engineers plans and drawings, Fort Hancock and Sandy hook proving ground, record group 7, drawer 44, Cartographic and Architectural branc, The National Archives, Washington, DC) from Talcott, T.M.R., plot of a survey of site, Fort at Sandy Hook, NJ, 1859-1860 Detail of engineer's wharf - U.S. Coast Guard Sandy Hook Station, Western Docking Structure, West of intersection of Canfield Road & Hartshorne Drive, Highlands, Monmouth County, NJ

50 CFR 679.20 - General limitations.

Code of Federal Regulations, 2014 CFR

2014-10-01

...% (ii) Trawl CP 50% 30% 20% (2) Hook-and-line CP and hook-and-line CV ≥60 ft (18.3 m) LOA 60% 40% no C...-and-line CV ≥60 ft (18.3 m) LOA 0.2 (4) Hook-and-line CP 48.7 (5) Pot CV ≥60 ft (18.3 m) LOA 8.4 (6) Pot CP 1.5 (7) AFA trawl CP 2.3 (8) Amendment 80 sector 13.4 (9) Trawl CV 22.1 (B) Incidental catch...

50 CFR 679.20 - General limitations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Type A season B season C season (1) Trawl 60% 20% 20% (i) Trawl CV 70% 10% 20% (ii) Trawl CP 50% 30% 20% (2) Hook-and-line CP and hook-and-line CV ≥60 ft (18.3 m) LOA 60% 40% no C season (3) Jig 40% 20% 40....3 m) LOA 0.2 (4) Hook-and-line CP 48.7 (5) Pot CV ≥60 ft (18.3 m) LOA 8.4 (6) Pot CP 1.5 (7) AFA...

Terrain Traversing Device Having a Wheel with Microhooks

NASA Technical Reports Server (NTRS)

Parness, Aaron (Inventor); McKenzie, Clifford F. (Inventor)

2014-01-01

A terrain traversing device includes an annular rotor element with a plurality of co-planar microspine hooks arranged on the periphery of the annular rotor element. Each microspine hook has an independently flexible suspension configuration that permits the microspine hook to initially engage an irregularity in a terrain surface at a preset initial engagement angle and subsequently engage the irregularity with a continuously varying engagement angle when the annular rotor element is rotated for urging the terrain traversing device to traverse a terrain surface.

Regenerative endodontic treatment of an immature tooth with a necrotic pulp and apical periodontitis using platelet-rich plasma (PRP) and mineral trioxide aggregate (MTA): a case report.

PubMed

Sachdeva, G S; Sachdeva, L T; Goel, M; Bala, S

2015-09-01

To report the successful clinical and radiographic outcome of a regenerative endodontic treatment. A 16-year-old male patient presented with a discoloured, maxillary left lateral incisor with a necrotic pulp. Radiographic examination revealed an incompletely developed root with an open apex. Under local anaesthesia and rubber dam isolation, an access cavity was prepared and the necrotic pulpal remnants were removed. The canal was disinfected without mechanical instrumentation with 5.25% NaOCl solution and dried with sterile paper points. A triple antibiotic (metronidazole, ciprofloxacin and minocycline) mixed with distilled water was packed in the canal and left for 28 days. Ten millimetres of whole blood was drawn by venipuncture from the patients antecubital vein for preparation of platelet-rich plasma (PRP). After removal of the antibiotic mixture, the PRP was injected into the canal space up to the cementoenamel junction level. Three millimetres of white MTA was placed directly over the PRP clot. Two days later, the tooth was restored with permanent filling materials. The patient was recalled for 3, 6, 12, 24 and 36 months clinical/radiographic follow-up. A 3-year follow-up radiograph revealed resolution of the periapical lesion, increased thickening of the root walls, further root development and continued apical closure of the root apex. The tooth was not responsive to cold tests; however, sensitivity tests with an electric pulp tester (EPT) elicited a delayed positive response. Regeneration is a viable treatment modality that allows continued root development of immature teeth with open apices and necrotic pulps. Platelet-rich plasma appears to be a suitable scaffold for regeneration of vital tissues in teeth with a necrotic pulps and an associated periapical lesion. Regenerative endodontic procedures may offer an effective treatment option to save teeth with compromised structural integrity. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.

46 CFR 71.25-25 - Hull equipment.

Code of Federal Regulations, 2013 CFR

2013-10-01

... testing and examination of chains, rings, hooks, shackles, swivels, and blocks; (5) Certification of the testing and examination of wire rope; (6) Certification of the heat treatment of chains, rings, hooks...

46 CFR 91.25-25 - Hull equipment.

Code of Federal Regulations, 2014 CFR

2014-10-01

... examination of chains, rings, hooks, shackles, swivels, and blocks; (5) Certification of the testing and examination of wire rope; (6) Certification of the heat-treatment of chains, rings, hooks, shackles, and...

46 CFR 91.25-25 - Hull equipment.

Code of Federal Regulations, 2013 CFR

2013-10-01

... examination of chains, rings, hooks, shackles, swivels, and blocks; (5) Certification of the testing and examination of wire rope; (6) Certification of the heat-treatment of chains, rings, hooks, shackles, and...

46 CFR 91.25-25 - Hull equipment.

Code of Federal Regulations, 2012 CFR

2012-10-01

... examination of chains, rings, hooks, shackles, swivels, and blocks; (5) Certification of the testing and examination of wire rope; (6) Certification of the heat-treatment of chains, rings, hooks, shackles, and...

46 CFR 71.25-25 - Hull equipment.

Code of Federal Regulations, 2014 CFR

2014-10-01

... testing and examination of chains, rings, hooks, shackles, swivels, and blocks; (5) Certification of the testing and examination of wire rope; (6) Certification of the heat treatment of chains, rings, hooks...

46 CFR 71.25-25 - Hull equipment.

Code of Federal Regulations, 2011 CFR

2011-10-01

... testing and examination of chains, rings, hooks, shackles, swivels, and blocks; (5) Certification of the testing and examination of wire rope; (6) Certification of the heat treatment of chains, rings, hooks...

46 CFR 91.25-25 - Hull equipment.

Code of Federal Regulations, 2011 CFR

2011-10-01

... examination of chains, rings, hooks, shackles, swivels, and blocks; (5) Certification of the testing and examination of wire rope; (6) Certification of the heat-treatment of chains, rings, hooks, shackles, and...

46 CFR 71.25-25 - Hull equipment.

Code of Federal Regulations, 2012 CFR

2012-10-01

... testing and examination of chains, rings, hooks, shackles, swivels, and blocks; (5) Certification of the testing and examination of wire rope; (6) Certification of the heat treatment of chains, rings, hooks...

Hook tool manufacture in New Caledonian crows: behavioural variation and the influence of raw materials.

PubMed

Klump, Barbara C; Sugasawa, Shoko; St Clair, James J H; Rutz, Christian

2015-11-18

New Caledonian crows use a range of foraging tools, and are the only non-human species known to craft hooks. Based on a small number of observations, their manufacture of hooked stick tools has previously been described as a complex, multi-stage process. Tool behaviour is shaped by genetic predispositions, individual and social learning, and/or ecological influences, but disentangling the relative contributions of these factors remains a major research challenge. The properties of raw materials are an obvious, but largely overlooked, source of variation in tool-manufacture behaviour. We conducted experiments with wild-caught New Caledonian crows, to assess variation in their hooked stick tool making, and to investigate how raw-material properties affect the manufacture process. In Experiment 1, we showed that New Caledonian crows' manufacture of hooked stick tools can be much more variable than previously thought (85 tools by 18 subjects), and can involve two newly-discovered behaviours: 'pulling' for detaching stems and bending of the tool shaft. Crows' tool manufactures varied significantly: in the number of different action types employed; in the time spent processing the hook and bending the tool shaft; and in the structure of processing sequences. In Experiment 2, we examined the interaction of crows with raw materials of different properties, using a novel paradigm that enabled us to determine subjects' rank-ordered preferences (42 tools by 7 subjects). Plant properties influenced: the order in which crows selected stems; whether a hooked tool was manufactured; the time required to release a basic tool; and, possibly, the release technique, the number of behavioural actions, and aspects of processing behaviour. Results from Experiment 2 suggested that at least part of the natural behavioural variation observed in Experiment 1 is due to the effect of raw-material properties. Our discovery of novel manufacture behaviours indicates a plausible scenario for the evolutionary origins, and gradual refinement, of New Caledonian crows' hooked stick tool making. Furthermore, our experimental demonstration of a link between raw-material properties and aspects of tool manufacture provides an alternative hypothesis for explaining regional differences in tool behaviours observed in New Caledonian crows, and some primate species.

Jurassic onychites (arm hooks) from squid-like cephalopods from the Wessex Basin, southern England

NASA Astrophysics Data System (ADS)

Hart, Malcolm; Hughes, Zoe; Page, Kevin; Price, Gregory; Smart, Christopher

2017-04-01

Modern coleoid (squid-like) cephalopods have arms that carry arrays of both suckers and hardened, organic hooks. Fossil arm hooks have been known since the description of Sternberg in 1823, although he identified them as algal remains. During the twentieth century there have been a number of descriptions of hooks (Kulicki & Szaniawski, 1972; Clarke & Engeser, 1988). Kulicki & Szaniawski (1972) gave these 'morphotypes' names using a binomial classification though, with many lacking defined (and figured) holotypes and, in some cases, only one recorded specimen, some of their designations should be regarded as invalid. Some of their morphotypes have, however, been reported widely, from DSDP sites on the Falkland Plateau as well as New Zealand, Germany, Svalbard, Poland and the United Kingdom. Exceptional soft-bodied preservation of species such as Belemnotheutis antiquus (Pearce, 1847) from the Callovian-Oxfordian of Wiltshire (UK) and Clarkeiteuthis montefiore (Buckman, 1880) from the Sinemurian of Dorset (UK) has allowed the identification of the host animal of some morphotypes, though the majority remain un-attributable. In the Christian Malford lagerstätte (Upper Callovian) of Wiltshire large numbers of hooks (including forms described as Acanthuncus, Arites, Deinuncus, Falcuncus, Longuncus and Paraglycerites) are found associated with an abundance of statoliths (cephalopod 'ear bones') and macrofossil evidence of both belemnites and teuthids, some of which includes exceptional soft-bodied preservation (Wilby et al., 2004; Hart et al., 2016). Many of the hook types cannot, at present be assigned to known taxa of coleoid. In Belemnotheutis antiquus there appears to be one form of simple, slightly curved hook and their shape appears to remain constant throughout the Callovian -Kimmeridgian interval. In the Lias Group, hooks of Clarkeiteuthis are very different, with inflated, often bi-lobate bases and each arm often characterised by the presence of different shapes of hook that are often arranged in pairs. Using the abundance of material available to us from the Wessex Basin, we are attempting to identify the host animals wherever this is possible. If this can be established then it may be possible, using micropalaeontological samples, to determine the stratigraphical and palaeoecological ranges of some of the host macro-fossils, many of which are otherwise rarely preserved outside known lagerstätte. A recently described specimen (Bristol Museum and Art Gallery, BRMSG Ce12385) of only the hooks associated with 4 arms can, therefore, be attributed to the Clarkeiteuthis lineage. Coming from the Lower Pliensbachian of the Dorset Coast this occurrence falls in the stratigraphical 'gap' between the known taxa of the Sinemurian (Clarkeiteuthis montefiore) and the Toarcian (Clarkeiteuthis conocauda). This specimen does, however, show paired hooks of different types, similar to another specimen in Manchester University Museum: this is not seen in C. conocauda and places the specimen in C. montefiore or a yet undescribed species of Clarkeiteuthis. Engeser, T.S. & Clarke, M.R. 1988. Cephalopod hooks, both recent and fossil. In: Clarke, M.R. & Trueman, E.R. (eds), Palaeontology and Neontology of Cephalopods, vol. 12,; Wilbur, K.M. (Ed.), The Mollusca, Academic press Inc., London, 133-151. Hart, M.B. & Hutchinson, D. in press. A newly described 'clarkeiteuthid' from the Lias Group of Dorset. Geoscience in South-West England. Hart, M.B., De Jonghe, A., Page, K.N., Price, G.D. & Smart, C.W. 2016. Exceptional accumulations of statoliths in association with the Christian Malford lagerstätte (Callovian, Jurassic) in Wiltshire, United Kingdom. Palaios, 31, 203-220. Kulicki, C. & Szaniawski, H. 1972. Cephalopod arm hooks from the Jurassic of Poland. Acta Palaeontologica Polonica, 17, 379-419. Wilby, P.R., Hudson, J.D., Clements, R.G. & Hollingworth, N.T.J. 2004. Taphonomy and origin of an accumulate of soft-bodied cephalopods in the Oxford Clay Formation (Jurassic, England). Palaeontology, 47, 1159-1180.

Functional, morphological and electrocardiographical abnormalities in patients with apical hypertrophic cardiomyopathy and apical aneurysm: correlation with cardiac MR

PubMed Central

Suwa, Kenichiro; Satoh, Hiroshi; Sano, Makoto; Nobuhara, Mamoru; Saitoh, Takeji; Saotome, Masao; Urushida, Tsuyoshi; Katoh, Hideki; Tawarahara, Kei; Ohtani, Hayato; Wakabayashi, Yasushi; Takase, Hiroyuki; Terada, Hajime; Takehara, Yasuo; Sakahara, Harumi; Hayashi, Hideharu

2014-01-01

Objective The prognosis of apical hypertrophic cardiomyopathy (APH) has been benign, but apical myocardial injury has prognostic importance. We studied functional, morphological and electrocardiographical abnormalities in patients with APH and with apical aneurysm and sought to find parameters that relate to apical myocardial injury. Methods Study design: a multicentre trans-sectional study. Patients: 45 patients with APH and 5 with apical aneurysm diagnosed with transthoracic echocardiography (TTE) in the database of Hamamatsu Circulation Forum. Measure: the apical contraction with cine-cardiac MR (CMR), the myocardial fibrotic scar with late gadolinium enhancement (LGE)-CMR, and QRS fragmentation (fQRS) defined when two ECG-leads exhibited RSR’s patterns. Results Cine-CMR revealed 27 patients with normal, 12 with hypokinetic and 11 with dyskinetic apical contraction. TTE misdiagnosed 11 (48%) patients with hypokinetic and dyskinetic contraction as those with normal contraction. Apical LGE was apparent in 10 (83%) and 11 (100%) patients with hypokinetic and dyskinetic contraction, whereas only in 11 patients (41%) with normal contraction (p<0.01). Patients with dyskinetic apical contraction had the lowest left ventricular ejection fraction, the highest prevalence of ventricular tachycardia, and the smallest ST depression and depth of negative T waves. The presence of fQRS was associated with impaired apical contraction and apical LGE (OR=8.32 and 8.61, p<0.05). Conclusions CMR is superior to TTE for analysing abnormalities of the apex in patients with APH and with apical aneurysm. The presence of fQRS can be a promising parameter for the early detection of apical myocardial injury. PMID:25332823

A Novel Approach for Apical Dissection During Robot-assisted Radical Prostatectomy: The "Collar" Technique.

PubMed

Bianchi, Lorenzo; Turri, Filippo Maria; Larcher, Alessandro; De Groote, Ruben; De Bruyne, Peter; De Coninck, Vincent; Goossens, Marijn; D'Hondt, Frederiek; De Naeyer, Geert; Schatteman, Peter; Mottrie, Alexandre

2018-02-02

Apical dissection in robot-assisted radical prostatectomy (RARP) affects not only cancer control, but also continence recovery. To describe a novel approach for apical dissection, the collar technique, to reduce apical positive surgical margins (PSMs). A total of 189 consecutive patients (81 in the control group, 108 in the collar technique group) underwent RARP at a single center. rates of apical PSMs; secondary outcome: urinary continence. The urethral sphincter complex is incised 2-3mm distally to the apex, to stay farther from it and reduce PSMs; the underlying smooth muscle is exposed and incised closer to the apex to preserve the maximal length of the lissosphincter. Mann-Whitney U and chi-square tests compared median and proportions between the two groups, respectively. Univariate logistic regression tested the association between technique employed and risk of apical PSMs. Fourteen patients (7.4%) revealed apical PSMs (9.9% in the control group, 5.6% in the collar group; p=0.7). When the collar technique was used, significantly lower rates of apical PSMs occurred in pT2 disease (0% vs 7.1%; p=0.03). In case of apical tumor at preoperative magnetic resonance imaging (MRI; n=43), the collar technique determined significantly lower overall (9.7% vs 42%) and apical (3.2% vs 42%) PSMs (all p≤0.02). Continence recovery in the collar and control groups was similar. When preoperative MRI showed an apical tumor, the collar technique had a significantly lower risk of apical PSMs (odds ratio: 0.05, p=0.009). The collar technique reduces the rates of apical PSMs in case of apical tumor, preserving the length of the lissosphincter. We describe a novel approach for apical dissection during robot-assisted radical prostatectomy. Our technique reduces the rates of apical surgical margins in case of apical tumor at preoperative magnetic resonance imaging and leads to optimal continence recovery. Copyright © 2018 European Association of Urology. Published by Elsevier B.V. All rights reserved.

Ineffective and prolonged apical contraction is associated with chest pain and ischaemia in apical hypertrophic cardiomyopathy.

PubMed

Stephenson, Edward; Monney, Pierre; Pugliese, Francesca; Malcolmson, James; Petersen, Steffen E; Knight, Charles; Mills, Peter; Wragg, Andrew; O'Mahony, Constantinos; Sekhri, Neha; Mohiddin, Saidi A

2018-01-15

To investigate the hypothesis that persistence of apical contraction into diastole is linked to reduced myocardial perfusion and chest pain. Apical hypertrophic cardiomyopathy (HCM) is defined by left ventricular (LV) hypertrophy predominantly of the apex. Hyperdynamic contractility resulting in obliteration of the apical cavity is often present. Apical HCM can lead to drug-refractory chest pain. We retrospectively studied 126 subjects; 76 with apical HCM and 50 controls (31 with asymmetrical septal hypertrophy (ASH) and 19 with non-cardiac chest pain and culprit free angiograms and structurally normal hearts). Perfusion cardiac magnetic resonance imaging (CMR) scans were assessed for myocardial perfusion reserve index (MPRi), late gadolinium enhancement (LGE), LV volumes (muscle and cavity) and regional contractile persistence (apex, mid and basal LV). In apical HCM, apical MPRi was lower than in normal and ASH controls (p<0.05). In apical HCM, duration of contractile persistence was associated with lower MPRi (p<0.01) and chest pain (p<0.05). In multivariate regression, contractile persistence was independently associated with chest pain (p<0.01) and reduced MPRi (p<0.001). In apical HCM, regional contractile persistence is associated with impaired myocardial perfusion and chest pain. As apical myocardium makes limited contributions to stroke volume, apical contractility is also largely ineffective. Interventions to reduce apical contraction and/or muscle mass are potential therapies for improving symptoms without reducing cardiac output. Copyright © 2017 Elsevier B.V. All rights reserved.

Asymmetric severe skeletal Class II division 1 patient with temporomandibular joint disorder treated with zygomatic anchorage devices and Ni-Ti alloy wires.

PubMed

Ishida, Takayoshi; Ono, Takashi

2014-09-01

To describe the orthodontic treatment of a nongrowing 30-year-old woman with asymmetric severe skeletal Class II malocclusions (asymmetric Angle Class II), large overjet (16 mm), large overbite (8 mm), two congenitally missing mandibular incisors (presenting a deciduous anterior tooth), and signs and symptoms of temporomandibular joint disorder (TMD). We used novel improved super-elastic Ni-Ti alloy wires (ISWs) combined with Ni-Ti alloy coil springs, power hooks, and a zygomatic implant as reinforced anchorage to provide a constant and continuous mild force to the dentition. We successfully distalized maxillary molars, premolars, and retracted anterior teeth and corrected the asymmetric Angle Class II molar relationship using this system of zygomatic anchorage in conjunction with ISWs, Ni-Ti alloy open-coil springs, and crimpable power hook. The maxillary molars were distalized, and postero-occlusal relationships were improved to achieve Class I canine and molar relationships on both sides. Intrusion of the upper molars made the mandibular plane close. Ideal overbite and overjet relationships were established. Facial esthetics were improved with decreased upper and lower lip protrusion, and no symptoms of TMD were observed after treatment. The orthodontic treatment described here is a promising anchorage technique alternative to traditional techniques to improve severe skeletal Class II with TMD.

Complete acromioclavicular joint dislocation treated with reconstructed ligament by trapezius muscle fascia and observation of fascial metaplasia.

PubMed

Wang, Chaoliang; Huang, Sufang; Wang, Yingzhen; Sun, Xuesheng; Zhu, Tao; Li, Qiang; Lin, Chu

2015-01-01

We evaluated the long-term clinical results of acute complete acromioclavicular dislocations treated by reconstruction of the acromioclavicular and coracoclavicular ligament using trapezius muscle fascia. Open reduction and internal fixation was performed using the clavicular hook plate in 12 patients with acute complete acromioclavicular joint dislocation, and the acromioclavicular and coracoclavicular ligaments were reconstructed using trapezius muscle fascia. Radiographic evaluations were conducted postoperatively. We evaluated the functional results with constant scoring system and radiological results at the final follow-up visit. The mean Constant score at the final follow-up visit was 91.67 (range, 81 to 100). The results were excellent in eight patients (66.7%) and good in four patients (33.3%). Three patients with scores from 80 to 90 had mild pain during activity, but this did not affect the range of motion of the shoulder. All patients have returned to their preoperative work without any limitations. Compared with the contralateral side, radiography showed anatomical reposition in the vertical plane in all cases. The hook-plate fixation with ligament reconstruction was successful in treating AC dislocations. The acromioclavicular and coracoclavicular ligament were reconstructed by trapezius muscle fascia that keep the distal clavicle stable both vertically and horizontally after type III injuries.

Complete acromioclavicular joint dislocation treated with reconstructed ligament by trapezius muscle fascia and observation of fascial metaplasia

PubMed Central

Wang, Chaoliang; Huang, Sufang; Wang, Yingzhen; Sun, Xuesheng; Zhu, Tao; Li, Qiang; Lin, Chu

2015-01-01

We evaluated the long-term clinical results of acute complete acromioclavicular dislocations treated by reconstruction of the acromioclavicular and coracoclavicular ligament using trapezius muscle fascia. Open reduction and internal fixation was performed using the clavicular hook plate in 12 patients with acute complete acromioclavicular joint dislocation, and the acromioclavicular and coracoclavicular ligaments were reconstructed using trapezius muscle fascia. Radiographic evaluations were conducted postoperatively. We evaluated the functional results with constant scoring system and radiological results at the final follow-up visit. The mean Constant score at the final follow-up visit was 91.67 (range, 81 to 100). The results were excellent in eight patients (66.7%) and good in four patients (33.3%). Three patients with scores from 80 to 90 had mild pain during activity, but this did not affect the range of motion of the shoulder. All patients have returned to their preoperative work without any limitations. Compared with the contralateral side, radiography showed anatomical reposition in the vertical plane in all cases. The hook-plate fixation with ligament reconstruction was successful in treating AC dislocations. The acromioclavicular and coracoclavicular ligament were reconstructed by trapezius muscle fascia that keep the distal clavicle stable both vertically and horizontally after type III injuries. PMID:28352721

Mitigating the Hook Effect in Lateral Flow Sandwich Immunoassays Using Real-Time Reaction Kinetics.

PubMed

Rey, Elizabeth G; O'Dell, Dakota; Mehta, Saurabh; Erickson, David

2017-05-02

The quantification of analyte concentrations using lateral flow assays is a low-cost and user-friendly alternative to traditional lab-based assays. However, sandwich-type immunoassays are often limited by the high-dose hook effect, which causes falsely low results when analytes are present at very high concentrations. In this paper, we present a reaction kinetics-based technique that solves this problem, significantly increasing the dynamic range of these devices. With the use of a traditional sandwich lateral flow immunoassay, a portable imaging device, and a mobile interface, we demonstrate the technique by quantifying C-reactive protein concentrations in human serum over a large portion of the physiological range. The technique could be applied to any hook effect-limited sandwich lateral flow assay and has a high level of accuracy even in the hook effect range.

Robert Hooke's model of memory.

PubMed

Hintzman, Douglas L

2003-03-01

In 1682 the scientist and inventor Robert Hooke read a lecture to the Royal Society of London, in which he described a mechanistic model of human memory. Yet few psychologists today seem to have heard of Hooke's memory model. The lecture addressed questions of encoding, memory capacity, repetition, retrieval, and forgetting--some of these in a surprisingly modern way. Hooke's model shares several characteristics with the theory of Richard Semon, which came more than 200 years later, but it is more complete. Among the model's interesting properties are that (1) it allows for attention and other top-down influences on encoding; (2) it uses resonance to implement parallel, cue-dependent retrieval; (3) it explains memory for recency; (4) it offers a single-system account of repetition priming; and (5) the power law of forgetting can be derived from the model's assumptions in a straightforward way.

A chromogranin A ELISA absent of an apparent high-dose hook effect observed in other chromogranin A ELISAs.

PubMed

Erickson, J Alan; Grenache, David G

2016-01-15

Routine testing for chromogranin A (CgA) using an established commercial ELISA revealed an apparent high-dose hook effect in approximately 15% of specimens. Investigations found the same effect in two additional ELISAs. We hypothesized that a CgA derived peptide(s) at high concentrations was responsible but experiments were inconclusive. Here we describe the analytical performance characteristics of the Chromoa™ CgA ELISA that did not display the apparent high-dose hook effect. Performance characteristics of the Chromoa ELISA were assessed. The reference interval was established utilizing healthy volunteers. Specimens producing the apparent high-dose hook effect in other assays were evaluated using the Chromoa ELISA. The limit of detection was 8ng/ml. Linearity was acceptable (slope=1.04, intercept=18.1 and r(2)=0.997). CVs were ≤4.6 and ≤9.3% for repeatability and within-laboratory imprecision, respectively. CgA was stable at ambient and refrigerated temperatures for a minimum of two and 14days, respectively. An upper reference interval limit of 95ng/ml was established. Specimens demonstrating the apparent high-dose hook effect in other ELISAs did not exhibit the phenomenon using the Chromoa ELISA. The Chromoa ELISA demonstrates acceptable performance for quantifying serum CgA. The apparent high-dose hook effect exhibited in other ELISAs was absent using the Chromoa assay. Copyright © 2015 Elsevier B.V. All rights reserved.

A novel mutation R190H in the AT-hook 1 domain of MeCP2 identified in an atypical Rett syndrome.

PubMed

Zhou, Xiao; Liao, Yuangao; Xu, Miaojing; Ji, Zhong; Xu, Yunqi; Zhou, Liang; Wei, Xiaoming; Hu, Peiqian; Han, Peng; Yang, Fanghan; Pan, Suyue; Hu, Yafang

2017-10-10

Mutations in Methyl-CpG binding protein 2 ( MECP2 ) have been identified as the disease-causing mutations in Rett Syndrome (RTT). However, no mutation in the AT-hook 1 domain of MECP2 has been reported in RTT yet. The function of AT-hook 1 domain of MECP2 has not been described either. The clinical and radiological features of a girl with progressive hyperactivity and loss of acquired linguistic and motor functions were presented. Next generation sequencing was used to screen the causative gene. Effect of the mutant protein on histone 3 methylation was assessed in vitro experiment. The patient was diagnosed with an atypical RTT at the age of nine. Magnetic resonance imaging revealed a loss of whole-brain volume and abnormal myelination. Genetic analysis identified a de novo novel missense mutation of MECP2 (NM_004992, c.570G->A, p.Arg190His). This mutation is located in the AT-hook 1 domain of MeCP2 protein. Overexpression of the mutant MeCP2 in cultured neuroblastoma cells SH-SY5Y revealed increased level of dimethylated histone 3 lysine 9, a transcriptional repressor marker. A novel missense mutation in AT-hook 1 domain of MeCP2 was identified in a patient with atypical RTT. Clinical data and in vitro experiment result imply that R190H mutation in AT-hook1 may cause dysfunction of MeCP2 and be a pathogenic variant.

View of Expedition 24 Crew Members in the MRM2

NASA Image and Video Library

2010-09-24

ISS024-E-015327 (24 Sept. 2010) --- Russian cosmonaut Alexander Skvortsov (right), Expedition 24 commander; NASA astronaut Tracy Caldwell Dyson and Russian cosmonaut Mikhail Kornienko, both flight engineers, pose for a photo during final preparations for their departure in the Soyuz TMA-18 docked to the Poisk Mini-Research Module 2 (MRM2) of the International Space Station. Originally scheduled for Sept. 23, the Soyuz undocked a day later due to a Poisk-side hatch sensor problem, which prevented hooks on the Poisk side of the docking interface from opening. The Soyuz undocked at 10:02 p.m. (EDT) on Sept. 24, 2010.

Synchrotron x-ray imaging of pulmonary alveoli in respiration in live intact mice

NASA Astrophysics Data System (ADS)

Chang, Soeun; Kwon, Namseop; Kim, Jinkyung; Kohmura, Yoshiki; Ishikawa, Tetsuya; Rhee, Chin Kook; Je, Jung Ho; Tsuda, Akira

2015-03-01

Despite nearly a half century of studies, it has not been fully understood how pulmonary alveoli, the elementary gas exchange units in mammalian lungs, inflate and deflate during respiration. Understanding alveolar dynamics is crucial for treating patients with pulmonary diseases. In-vivo, real-time visualization of the alveoli during respiration has been hampered by active lung movement. Previous studies have been therefore limited to alveoli at lung apices or subpleural alveoli under open thorax conditions. Here we report direct and real-time visualization of alveoli of live intact mice during respiration using tracking X-ray microscopy. Our studies, for the first time, determine the alveolar size of normal mice in respiration without positive end expiratory pressure as 58 +/- 14 (mean +/- s.d.) μm on average, accurately measured in the lung bases as well as the apices. Individual alveoli of normal lungs clearly show heterogeneous inflation from zero to ~25% (6.7 +/- 4.7% (mean +/- s.d.)) in size. The degree of inflation is higher in the lung bases (8.7 +/- 4.3% (mean +/- s.d.)) than in the apices (5.7 +/- 3.2% (mean +/- s.d.)). The fraction of the total tidal volume allocated for alveolar inflation is 34 +/- 3.8% (mean +/- s.e.m). This study contributes to the better understanding of alveolar dynamics and helps to develop potential treatment options for pulmonary diseases.

The iRoCS Toolbox--3D analysis of the plant root apical meristem at cellular resolution.

PubMed

Schmidt, Thorsten; Pasternak, Taras; Liu, Kun; Blein, Thomas; Aubry-Hivet, Dorothée; Dovzhenko, Alexander; Duerr, Jasmin; Teale, William; Ditengou, Franck A; Burkhardt, Hans; Ronneberger, Olaf; Palme, Klaus

2014-03-01

To achieve a detailed understanding of processes in biological systems, cellular features must be quantified in the three-dimensional (3D) context of cells and organs. We described use of the intrinsic root coordinate system (iRoCS) as a reference model for the root apical meristem of plants. iRoCS enables direct and quantitative comparison between the root tips of plant populations at single-cell resolution. The iRoCS Toolbox automatically fits standardized coordinates to raw 3D image data. It detects nuclei or segments cells, automatically fits the coordinate system, and groups the nuclei/cells into the root's tissue layers. The division status of each nucleus may also be determined. The only manual step required is to mark the quiescent centre. All intermediate outputs may be refined if necessary. The ability to learn the visual appearance of nuclei by example allows the iRoCS Toolbox to be easily adapted to various phenotypes. The iRoCS Toolbox is provided as an open-source software package, licensed under the GNU General Public License, to make it accessible to a broad community. To demonstrate the power of the technique, we measured subtle changes in cell division patterns caused by modified auxin flux within the Arabidopsis thaliana root apical meristem. © 2014 The Authors The Plant Journal © 2014 John Wiley & Sons Ltd.

The Impact of Apical Patency in the Success of Endodontic Treatment of Necrotic Teeth with Apical Periodontitis: A Brief Review.

PubMed

Machado, Ricardo; Ferrari, Carlos Henrique; Back, Eduardo; Comparin, Daniel; Tomazinho, Luiz Fernando; Vansan, Luiz Pascoal

2016-01-01

Accumulation of soft tissue or dentinal remnants in the apical region is a common event that can cause blockage of root canals. This event can be avoided if apical patency is performed during the root canal shaping procedures. However, there is no consensus on the role of apical patency in relation to the success of endodontic treatment of necrotic teeth with apical periodontitis. Therefore, the purpose of this paper was to conduct a brief review on the role of apical patency in guaranteeing the success of endodontic treatments of necrotic teeth with apical periodontitis considering two other key points; the root canal anatomy and microbiology.

75 FR 75934 - Airworthiness Directives; Apical Industries Inc. (Apical) Emergency Float Kits

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-07

...-1190; Directorate Identifier 2010-SW-038-AD] RIN 2120-AA64 Airworthiness Directives; Apical Industries Inc. (Apical) Emergency Float Kits AGENCY: Federal Aviation Administration, DOT. ACTION: Notice of... the Apical emergency float kits installed on certain model helicopters under supplemental type...

Micro-CT evaluation of apical delta morphologies in human teeth.

PubMed

Gao, Xianhua; Tay, Franklin R; Gutmann, James L; Fan, Wei; Xu, Ting; Fan, Bing

2016-11-07

The apical delta is an intricate system within the root canal and incompletely debridement may affect the long-term prognosis of root canal therapy. The aim of the present study is to investigate the morphologic features of apical deltas in human teeth with micro-computed tomography (micro-CT) using a centreline-fitting algorithm. One hundred and thirty-six apical deltas were detected in 1400 teeth. Molars had more apical deltas (15.8%) than anterior teeth (6.3%). In maxillary molars, the mesiobuccal root had a significantly higher prevalence of apical delta than the palatal root or the distobuccal root. The median vertical distance of the apical delta was 1.87 mm with 13% more than 3 mm. The median diameter and length of the apical delta branches were 132.3 and 934.5 μm. Apical delta branches were not straight with cross-sectional shapes being non-circular. These morphological features of apical delta may complicate debridement of the infected root canal system.

Trafficking Ion Transporters to the Apical Membrane of Polarized Intestinal Enterocytes.

PubMed

Engevik, Amy Christine; Goldenring, James R

2018-01-02

Epithelial cells lining the gastrointestinal tract require distinct apical and basolateral domains to function properly. Trafficking and insertion of enzymes and transporters into the apical brush border of intestinal epithelial cells is essential for effective digestion and absorption of nutrients. Specific critical ion transporters are delivered to the apical brush border to facilitate fluid and electrolyte uptake. Maintenance of these apical transporters requires both targeted delivery and regulated membrane recycling. Examination of altered apical trafficking in patients with Microvillus Inclusion disease caused by inactivating mutations in MYO5B has led to insights into the regulation of apical trafficking by elements of the apical recycling system. Modeling of MYO5B loss in cell culture and animal models has led to recognition of Rab11a and Rab8a as critical regulators of apical brush border function. All of these studies show the importance of apical membrane trafficking dynamics in maintenance of polarized epithelial cell function. Copyright © 2018 Cold Spring Harbor Laboratory Press; all rights reserved.

A Sticky Chain Model of the Elongation and Unfolding of Escherichia coli P Pili under Stress

PubMed Central

Andersson, Magnus; Fällman, Erik; Uhlin, Bernt Eric; Axner, Ove

2006-01-01

A model of the elongation of P pili expressed by uropathogenic Escherichia coli exposed to stress is presented. The model is based upon the sticky chain concept, which is based upon Hooke's law for elongation of the layer-to-layer and head-to-tail bonds between neighboring units in the PapA rod and a kinetic description of the opening and closing of bonds, described by rate equations and an energy landscape model. It provides an accurate description of the elongation behavior of P pili under stress and supports a hypothesis that the PapA rod shows all three basic stereotypes of elongation/unfolding: elongation of bonds in parallel, the zipper mode of unfolding, and elongation and unfolding of bonds in series. The two first elongation regions are dominated by a cooperative bond opening, in which each bond is influenced by its neighbor, whereas the third region can be described by individual bond opening, in which the bonds open and close randomly. A methodology for a swift extraction of model parameters from force-versus-elongation measurements performed under equilibrium conditions is derived. Entities such as the free energy, the stiffness, the elastic elongation, the opening length of the various bonds, and the number of PapA units in the rod are determined. PMID:16361334

A sticky chain model of the elongation and unfolding of Escherichia coli P pili under stress.

PubMed

Andersson, Magnus; Fällman, Erik; Uhlin, Bernt Eric; Axner, Ove

2006-03-01

A model of the elongation of P pili expressed by uropathogenic Escherichia coli exposed to stress is presented. The model is based upon the sticky chain concept, which is based upon Hooke's law for elongation of the layer-to-layer and head-to-tail bonds between neighboring units in the PapA rod and a kinetic description of the opening and closing of bonds, described by rate equations and an energy landscape model. It provides an accurate description of the elongation behavior of P pili under stress and supports a hypothesis that the PapA rod shows all three basic stereotypes of elongation/unfolding: elongation of bonds in parallel, the zipper mode of unfolding, and elongation and unfolding of bonds in series. The two first elongation regions are dominated by a cooperative bond opening, in which each bond is influenced by its neighbor, whereas the third region can be described by individual bond opening, in which the bonds open and close randomly. A methodology for a swift extraction of model parameters from force-versus-elongation measurements performed under equilibrium conditions is derived. Entities such as the free energy, the stiffness, the elastic elongation, the opening length of the various bonds, and the number of PapA units in the rod are determined.

Buckling Instabilities and Complex Dynamics in a Model of Uniflagellar Bacterial Locomotion

NASA Astrophysics Data System (ADS)

Nguyen, Frank; Graham, Michael

2015-11-01

Locomotion of microorganisms at low Reynolds number is a long studied problem. Of particular interest are organisms using a single flagellum to undergo a wide range of motions: pushing, pulling, and tumbling or flicking. Recent experiments have connected the stability of the hook protein, connecting cell motor and flagellum, to deviations from typical straight swimming trajectories. We seek physical explanations to these phenomena by developing a computationally inexpensive, rigid-body dynamic model of a uniflagellated organism with a flexible hook connection that captures the fundamental dynamics, kinematics, and configurations. Furthermore, the model addresses the effects of hook loading and geometry on the stability of the system. Simulations with low hook flexibility produce the classic straight trajectory, but a large flexibility produces helical trajectories, leading to directional changes when coupled with transient hook stiffening. Minima for critical flexibilities are found in certain subsets of parameter space, implying preferred geometries for certain swimming dynamics. The model verifies proposed mechanisms for swimming in various modes and highlights the role of flexibility in the biology of real organisms and the engineering of artificial microswimmers. This work was supported by NSF grant PHY-1304942.

Morphometric characteristics of the metacestode Echinococcus vogeli Rausch & Bernstein, 1972 in human infections from the northern region of Brazil.

PubMed

Almeida, F; Oliveira, F; Neves, R; Siqueira, N; Rodrigues-Silva, R; Daipert-Garcia, D; Machado-Silva, J R

2015-07-01

Polycystic echinococcosis, caused by the larval stage (metacestode) of the small-sized tapeworm, Echinococcus vogeli, is an emerging parasitic zoonosis of great public health concern in the humid tropical rainforests of South and Central America. Because morphological and morphometric characteristics of the metacestode are not well known, hydatid cysts from the liver and the mesentery were examined from patients following surgical procedures. Whole mounts of protoscoleces with rostellar hooks were examined under light and confocal laser scanning microscopy. Measurements were made of both large and small hooks, including the total area, total length, total width, blade area, blade length, blade width, handle area, handle length and handle width. The results confirmed the 1:1 arrangement of hooks in the rostellar pad and indicated, for the first time, that the morphometry of large and small rostellar hooks varies depending upon the site of infection. Light and confocal microscopy images displayed clusters of calcareous corpuscles in the protoscoleces. In conclusion, morphological features of large and small rostellar hooks of E. vogeli are adapted to a varied environment within the vertebrate host and such morphological changes in calcareous corpuscles occur at different stages in the maturation of metacestodes.

Sandy Hook Traveler Information System

DOT National Transportation Integrated Search

2010-09-01

This report focuses on equipment and procedural solutions for gathering and disseminating a wide range of visitor information, including real-time traveler information data relating to traffic and parking at the Sandy Hook Unit of the Gateway Recreat...

Dental age estimation of growing children by measurement of open apices: A Malaysian formula

PubMed Central

Cugati, Navaneetha; Kumaresan, Ramesh; Srinivasan, Balamanikanda; Karthikeyan, Priyadarshini

2015-01-01

Background: Age estimation is of prime importance in forensic science and clinical dentistry. Age estimation based on teeth development is one reliable approach. Many radiographic methods are proposed on the Western population for estimating dental age, and a similar assessment was found to be inadequate in Malaysian population. Hence, this study aims at formulating a regression model for dental age estimation in Malaysian children population using Cameriere's method. Materials and Methods: Orthopantomographs of 421 Malaysian children aged between 5 and 16 years involving all the three ethnic origins were digitalized and analyzed using Cameriere's method of age estimation. The subjects’ age was modeled as a function of the morphological variables, gender (g), ethnicity, sum of normalized open apices (s), number of tooth with completed root formation (N0) and the first-order interaction between s and N0. Results: The variables that contributed significantly to the fit were included in the regression model, yielding the following formula: Age = 11.368-0.345g + 0.553No -1.096s - 0.380s.No, where g is a variable, 1 for males and 2 for females. The equation explained 87.1% of total deviance. Conclusion: The results obtained insist on reframing the original Cameriere's formula to suit the population of the nation specifically. Further studies are to be conducted to evaluate the applicability of this formula on a larger sample size. PMID:26816464

Thorascopic resection of an apical paraspinal schwannoma using the da Vinci surgical system.

PubMed

Finley, David; Sherman, Jonathan H; Avila, Edward; Bilsky, Mark

2014-01-01

Posterior mediastinal neurogenic tumors have traditionally been resected via an open posterolateral thoracotomy. Video-assisted thorascopic surgery has emerged as an alternative technique allowing for improved morbidity with decreased blood loss, less postoperative pain, and a shorter recovery period, among others. The da Vinci surgical system, as first described for urologic procedures, has recently been reported for lung lobectomy. This technique provides the advantages of instrumentation with 6 degrees of freedom, stable operating arms, and improved visualization with the three-dimensional high-definition camera. We describe the technique for thorascopic resection of an apical paraspinal schwannoma of the T1 nerve root with the da Vinci surgical system. This technique used a specialized intraoperative neuromonitoring probe for free-running electromyography (EMG) and triggered EMG. We demonstrate successful resection of a posterior paraspinal schwannoma with the da Vinci surgical system while preserving neurologic function. The patient displayed stable intraoperative monitoring of the T1 nerve root and full intrinsic hand strength postoperatively. The technique described in this article introduces robotic system accuracy and precludes the need for an open thoracotomy. In addition, this approach demonstrates the ability of the da Vinci surgical system to safely dissect tumors from their neural attachments and is applicable to other such lesions of similar size and location. Georg Thieme Verlag KG Stuttgart · New York.

Plato crater, first observative session: not any "hook" but a shark fin? (Italian Title: La 1° Campagna Osservativa del cratere Plato: non un "uncino" ma una "pinna di squalo"?)

NASA Astrophysics Data System (ADS)

Mercatali, A.

2018-01-01

On 1st March 2012 an observative session of Moon's Plato crater was made. The purpose of these observations was to check the presence of one shadow with "hook" form at the inner of Plato crater already reported by H. Percy Wilkins, 3th April 21:30 UT, 1952. The results obtained by us have not shown any shadow with an hook form, but a shadow like a shark fin.

Multiple piece turbine blade/vane

DOEpatents

Kimmel, Keith D

2013-02-05

An air cooled turbine blade or vane of a spar and shell construction with the shell made from a high temperature resistant material that must be formed from an EDM process. The shell and the spar both have a number of hooks extending in a spanwise direction and forming a contact surface that is slanted such that a contact force increases as the engaging hooks move away from one another. The slanted contact surfaces on the hooks provides for an better seal and allows for twisting between the shell and the spar while maintaining a tight fit.

Dbl3 drives Cdc42 signaling at the apical margin to regulate junction position and apical differentiation

PubMed Central

Zihni, Ceniz; Munro, Peter M.G.; Elbediwy, Ahmed; Keep, Nicholas H.; Terry, Stephen J.; Harris, John

2014-01-01

Epithelial cells develop morphologically characteristic apical domains that are bordered by tight junctions, the apical–lateral border. Cdc42 and its effector complex Par6–atypical protein kinase c (aPKC) regulate multiple steps during epithelial differentiation, but the mechanisms that mediate process-specific activation of Cdc42 to drive apical morphogenesis and activate the transition from junction formation to apical differentiation are poorly understood. Using a small interfering RNA screen, we identify Dbl3 as a guanine nucleotide exchange factor that is recruited by ezrin to the apical membrane, that is enriched at a marginal zone apical to tight junctions, and that drives spatially restricted Cdc42 activation, promoting apical differentiation. Dbl3 depletion did not affect junction formation but did affect epithelial morphogenesis and brush border formation. Conversely, expression of active Dbl3 drove process-specific activation of the Par6–aPKC pathway, stimulating the transition from junction formation to apical differentiation and domain expansion, as well as the positioning of tight junctions. Thus, Dbl3 drives Cdc42 signaling at the apical margin to regulate morphogenesis, apical–lateral border positioning, and apical differentiation. PMID:24379416

Immediate autotransplantation of mandibular third molar in China.

PubMed

Yan, Quanmei; Li, Bo; Long, Xing

2010-10-01

Tooth autotransplantation is a useful surgical method to replace a nonrestorable tooth. We reported our experiences in the replacement of mandibular nonrestorable molars by immediate autotransplantation in a Chinese population. Thirty-five mandibular third molars with open or closed apices from 34 patients were autotransplanted into the same or contralateral fresh recipient sites immediately after the extraction of the nonrestorable mandibular molars. Root canal treatment was routinely performed in the closed-apical molars within 1 month after surgery. Clinical and radiographic examination of the transplanted donor molars was done after surgery. Two teeth were been extracted for progressive root resorption. The remaining 33 autotransplanted teeth were asymptomatic and functioning after a mean follow-up period of 5.2 years. No infection, ankylosis, loss of the transplants, or root resorption was noted in the remaining autotransplanted teeth. Immediate autotransplantation of the mandibular third molar is a reasonable and alternative treatment to replace a nonrestorable tooth in China. Copyright © 2010 Mosby, Inc. All rights reserved.

Conservation Hotspots for the Turtles on the High Seas of the Atlantic Ocean

PubMed Central

Huang, Hsiang-Wen

2015-01-01

Understanding the distribution of bycaught sea turtles could inform conservation strategies and priorities. This research analyses the distribution of turtles caught as longline fisheries bycatch on the high seas of the Atlantic Ocean. This research collected 18,142 bycatch observations and 47.1 million hooks from large-scale Taiwanese longline vessels in the Atlantic Ocean from June 2002 to December 2013. The coverage rates were ranged from 0.48% to 17.54% by year. Seven hundred and sixty-seven turtles were caught, and the major species were leatherback (59.8%), olive ridley (27.1%) and loggerhead turtles (8.7%). Most olive ridley (81.7%) and loggerhead (82.1%) turtles were hooked, while the leatherbacks were both hooked (44.0%) and entangled (31.8%). Depending on the species, 21.4% to 57.7% were dead when brought onboard. Most of the turtles were caught in tropical areas, especially in the Gulf of Guinea (15°N-10°S, 30°W-10°E), but loggerheads were caught in the south Atlantic Ocean (25°S-35°S, 40°W-10°E and 30°S-40°S, 55°W-45°W). The bycatch rate was the highest at 0.030 per 1000 hooks for leatherbacks in the tropical area. The bycatch rates of olive ridley ranged from 0 to 0.010 per thousand hooks. The loggerhead bycatch rates were higher in the northern and southern Atlantic Ocean and ranged from 0.0128 to 0.0239 per thousand hooks. Due to the characteristics of the Taiwanese deep-set longline fleet, bycatch rates were lower than those of coastal longline fisheries, but mortality rates were higher because of the long hours of operation. Gear and bait modification should be considered to reduce sea turtle bycatch and increase survival rates while reducing the use of shallow hooks would also be helpful. PMID:26267796

Six species of Acanthobothrium (Eucestoda: Tetraphyllidea) in stingrays (Chondrichthyes: Rajiformes: Myliobatoidei) from Ecuador.

PubMed

Marguee, F; Brooks, D R; Barriga, R

1997-06-01

Six species of Acanthobothrium, 4 described as new, are reported in stingrays from southern Ecuador. Acanthobothrium atahualpai n. sp. in Gymnura afuerae most closely resembles Acanthobothrium fogeli and Acanthobothrium parviuncinatum by having bothridial hooks with recurved prongs and short handles. It differs from A. fogeli by having bothridial hooks 163-195 microns vs. 78-114 microns long and averaging 25 vs. 32 testes per pruglottis: it differs from A. parviuncinatum by having bothridial hooks 163-195 microns vs. 87 microns long and averaging 25 vs. 13 testes per proglottis. Acanthobothrium minusculus n. sp. in Urolophus tumbesensis most resembles Acanthobothrium campbelli and Acanthobothrium vargasi by being no more than 3 mm long and having 6-30 testes per proglottis. It can be distinguished from them by having bothridial hooks averaging 86 microns vs. 108-111 microns and 130-133 microns long, and 6-10 vs. 15-23 and 22-29 testes per proglottis, respectively. Acanthobothrium monksi n. sp. in Aetobatus narinari resembles Acanthobothrium tasajerasi from Himantura schmardae by having a prominent genital atrium and a large globose cirrus sac; it differs by averaging 21 vs. 35 testes per proglottis and having bothridial hooks averaging 150 microns vs. 165 microns long. Acanthobothrium obuncus n. sp. in Dasyatis longus resembles a group of species characterized by wider than long to square immature and mature proglottides, bothridia at least partially fused to the scolex at their posterior ends, and asymmetrical ovarian arms with aporal arms extending anteriorly to the vaginal level. It resembles Acanthobothrium americanum by averaging 73 vs. 72 testes per proglottis, but differs by having bothridial hooks averaging 120-131 microns vs. 151 microns long; it resembles Acanthobothrium chilensis by having bothridial hooks averaging 120-131 microns vs. 130 microns long, but differs by averaging 73 vs. 90 testes per proglottis. Acanthobothrium campbelli in Urotrygon chilensis and Acanthobothrium costarricense in Dasyatis longus, previously known in those hosts from the Pacific coast of Costa Rica, are reported from Ecuador for the first time.

Conservation hotspots for the turtles on the high seas of the Atlantic Ocean.

PubMed

Huang, Hsiang-Wen

2015-01-01

Understanding the distribution of bycaught sea turtles could inform conservation strategies and priorities. This research analyses the distribution of turtles caught as longline fisheries bycatch on the high seas of the Atlantic Ocean. This research collected 18,142 bycatch observations and 47.1 million hooks from large-scale Taiwanese longline vessels in the Atlantic Ocean from June 2002 to December 2013. The coverage rates were ranged from 0.48% to 17.54% by year. Seven hundred and sixty-seven turtles were caught, and the major species were leatherback (59.8%), olive ridley (27.1%) and loggerhead turtles (8.7%). Most olive ridley (81.7%) and loggerhead (82.1%) turtles were hooked, while the leatherbacks were both hooked (44.0%) and entangled (31.8%). Depending on the species, 21.4% to 57.7% were dead when brought onboard. Most of the turtles were caught in tropical areas, especially in the Gulf of Guinea (15°N-10°S, 30°W-10°E), but loggerheads were caught in the south Atlantic Ocean (25°S-35°S, 40°W-10°E and 30°S-40°S, 55°W-45°W). The bycatch rate was the highest at 0.030 per 1000 hooks for leatherbacks in the tropical area. The bycatch rates of olive ridley ranged from 0 to 0.010 per thousand hooks. The loggerhead bycatch rates were higher in the northern and southern Atlantic Ocean and ranged from 0.0128 to 0.0239 per thousand hooks. Due to the characteristics of the Taiwanese deep-set longline fleet, bycatch rates were lower than those of coastal longline fisheries, but mortality rates were higher because of the long hours of operation. Gear and bait modification should be considered to reduce sea turtle bycatch and increase survival rates while reducing the use of shallow hooks would also be helpful.

Modeling of traction-coupling properties of wheel propulsor

NASA Astrophysics Data System (ADS)

Sakhapov, R. L.; Nikolaeva, R. V.; Gatiyatullin, M. H.; Makhmutov, M. M.

2017-12-01

In conditions of operation of aggregates on soils with low bearing capacity, the main performance indicators of their operation are determined by the properties of retaining the functional qualities of the propulsor. Therefore, the parameters of the anti-skid device can not be calculated by only one criterion. The equipment of propellers with anti-skid devices, which allow to reduce the compaction effect of the propulsion device on the soil, seems to be a rational solution to the problem of increasing traction and coupling properties of the driving wheels. The mathematical model is based on the study of the interaction of the driving wheel with anti-skid devices and a deformable bearing surface, which takes into account the wheel diameter, skid coefficient, the parameters of the anti-skid device, the physical and mechanical properties of the soil. As a basic mathematical model that determines the dependence of the coupling properties on the wheel parameters, the model obtained as a result of integration and reflecting the process of soil deformation from the shear stress is adopted. The total value of the resistance forces will determine the force of the hitch pressure on the horizontal soil layers, and the value of its deformation is the degree of wheel slippage. When the anti-skid devices interact with the soil, the traction capacity of the wheel is composed of shear forces, soil shear and soil deformation forces with detachable hooks. As a result of the interaction of the hook with the soil, the latter presses against the walls of the hook with the force equal to the sum of the hook load and the resistance to movement. During operation, the linear dimensions of the hook will decrease, which is not taken into account by the safety factor. Abrasive wear of the thickness of the hook is approximately proportional to the work of friction caused by the movement of the hook when inserted into the soil and slipping the wheel.

Cooperative binding mitigates the high-dose hook effect.

PubMed

Roy, Ranjita Dutta; Rosenmund, Christian; Stefan, Melanie I

2017-08-14

The high-dose hook effect (also called prozone effect) refers to the observation that if a multivalent protein acts as a linker between two parts of a protein complex, then increasing the amount of linker protein in the mixture does not always increase the amount of fully formed complex. On the contrary, at a high enough concentration range the amount of fully formed complex actually decreases. It has been observed that allosterically regulated proteins seem less susceptible to this effect. The aim of this study was two-fold: First, to investigate the mathematical basis of how allostery mitigates the prozone effect. And second, to explore the consequences of allostery and the high-dose hook effect using the example of calmodulin, a calcium-sensing protein that regulates the switch between long-term potentiation and long-term depression in neurons. We use a combinatorial model of a "perfect linker protein" (with infinite binding affinity) to mathematically describe the hook effect and its behaviour under allosteric conditions. We show that allosteric regulation does indeed mitigate the high-dose hook effect. We then turn to calmodulin as a real-life example of an allosteric protein. Using kinetic simulations, we show that calmodulin is indeed subject to a hook effect. We also show that this effect is stronger in the presence of the allosteric activator Ca 2+ /calmodulin-dependent kinase II (CaMKII), because it reduces the overall cooperativity of the calcium-calmodulin system. It follows that, surprisingly, there are conditions where increased amounts of allosteric activator actually decrease the activity of a protein. We show that cooperative binding can indeed act as a protective mechanism against the hook effect. This will have implications in vivo where the extent of cooperativity of a protein can be modulated, for instance, by allosteric activators or inhibitors. This can result in counterintuitive effects of decreased activity with increased concentrations of both the allosteric protein itself and its allosteric activators.

Clinical efficacies of coracoclavicular ligament reconstruction using suture anchor versus hook plate in the treatment of distal clavicle fracture.

PubMed

Yan, H W; Li, L; Wang, R C; Yang, Y; Xie, Y; Tang, J; Shi, Z Y

2017-12-01

Comparison of clinical efficacies between coracoclavicular ligament reconstruction using autologous gracilis tendon with suture anchor and clavicular hook plate for the treatment of acute Neer type II distal clavicle fracture. Both coracoclavicular reconstruction with autologous gracilis tendon and clavicular hook plate could achieve satisfactory results for treating acute Neer type II distal clavicle fracture. Acute Neer type II distal clavicle fracture patients enrolled in this prospective randomized study were divided into the coracoclavicular ligament reconstruction group (using autologous gracilis tendon and suture anchor) and the hook plate group. Clinical outcomes were evaluated by shoulder X-ray, forward flexion, abduction and external rotation angle, Constant-Murley shoulder score and pain Visual Analogue Scale (VAS) at each follow-up for up to 24 months. The current study enrolled a total of 42 acute Neer type II distal clavicle fracture patients attended our hospital from March 2010 to December 2013. All patients had achieved complete healing and followed up for an average of 26 months (range, 24-38 months). At 3-month and 6-month follow-ups, Constant-Murley score in the ligament reconstruction group was significantly higher (93.8±2.6 vs. 88.7±8.7; 95.9±2.7 vs. 93.0±7.0, P<0.05), while VAS score was poorer than those in the hook plate group (1.6±0.8 vs. 2.5±1.9; 1.1±1.0 vs. 1.6±1.7, P<0.05). Reconstruction with autologous gracilis tendon improved VAS pain score in early postoperation follow-up; while Constant-Murley score and VAS score were significantly improved in the hook plate group after the implant was removed. These suggested that both coracoclavicular reconstruction with autologous gracilis tendon and clavicular hook plate could achieve satisfactory results. Level II, low-powered prospective randomized trial. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Structures of transcription pre-initiation complex with TFIIH and Mediator.

PubMed

Schilbach, S; Hantsche, M; Tegunov, D; Dienemann, C; Wigge, C; Urlaub, H; Cramer, P

2017-11-09

For the initiation of transcription, RNA polymerase II (Pol II) assembles with general transcription factors on promoter DNA to form the pre-initiation complex (PIC). Here we report cryo-electron microscopy structures of the Saccharomyces cerevisiae PIC and PIC-core Mediator complex at nominal resolutions of 4.7 Å and 5.8 Å, respectively. The structures reveal transcription factor IIH (TFIIH), and suggest how the core and kinase TFIIH modules function in the opening of promoter DNA and the phosphorylation of Pol II, respectively. The TFIIH core subunit Ssl2 (a homologue of human XPB) is positioned on downstream DNA by the 'E-bridge' helix in TFIIE, consistent with TFIIE-stimulated DNA opening. The TFIIH kinase module subunit Tfb3 (MAT1 in human) anchors the kinase Kin28 (CDK7), which is mobile in the PIC but preferentially located between the Mediator hook and shoulder in the PIC-core Mediator complex. Open spaces between the Mediator head and middle modules may allow access of the kinase to its substrate, the C-terminal domain of Pol II.

Astronaut James Newman with latch hook for tether device

NASA Technical Reports Server (NTRS)

1993-01-01

Astronaut James H. Newman, mission specialist, shows off a latch hook for a tether device used during the STS-51 extravehicular activity (EVA) on September 16, 1993. Newman, on Discovery's middeck, appears surrounded by sleep restraints.

Wronskian solutions of the T-, Q- and Y-systems related to infinite dimensional unitarizable modules of the general linear superalgebra gl (M | N)

NASA Astrophysics Data System (ADS)

Tsuboi, Zengo

2013-05-01

In [1] (Z. Tsuboi, Nucl. Phys. B 826 (2010) 399, arxiv:arXiv:0906.2039), we proposed Wronskian-like solutions of the T-system for [ M , N ]-hook of the general linear superalgebra gl (M | N). We have generalized these Wronskian-like solutions to the ones for the general T-hook, which is a union of [M1 ,N1 ]-hook and [M2 ,N2 ]-hook (M =M1 +M2, N =N1 +N2). These solutions are related to Weyl-type supercharacter formulas of infinite dimensional unitarizable modules of gl (M | N). Our solutions also include a Wronskian-like solution discussed in [2] (N. Gromov, V. Kazakov, S. Leurent, Z. Tsuboi, JHEP 1101 (2011) 155, arxiv:arXiv:1010.2720) in relation to the AdS5 /CFT4 spectral problem.

Clavicular hook plate for grade-III acromioclavicular dislocation.

PubMed

Steinbacher, Gilbert; Sallent, Andrea; Seijas, Roberto; Boffa, Juan Manuel; Espinosa, Wenceslao; Cugat, Ramón

2014-12-01

To review the outcomes of clavicular hook plate fixation for grade-III acromioclavicular (AC) dislocation in young athletes. Medical records of 14 male and 5 female athletes aged 18 to 49 (mean, 29) years who underwent fixation with a 3.5-mm-thick, 15-mm-long clavicular hook plate for acute grade-III AC dislocation were reviewed. The visual analogue score for pain and the Constant shoulder score were assessed. The mean follow-up was 4.2 years. The mean visual analogue score for pain was 1.8 (range, 1-3). The Constant shoulder score was excellent (≥ 90) in 14 patients and good (83-89) in 5 patients. All patients achieved range of motion equal to that of the contralateral side at week 5. Sports activities were resumed by month 6 at the latest. The clavicular hook plate for grade- III AC dislocation enables quick return to sports activities and achieves good-to-excellent functional outcome.

Friction stir scribe welding technique for dissimilar joining of aluminium and galvanised steel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Tianhao; Sidhar, Harpreet; Mishra, Rajiv S.

Friction stir scribe technology, a derivative of friction stir welding, was applied for the dissimilar lap welding of an aluminum alloy and galvanized mild steel sheets. During the process, the rotating tool with a cobalt steel scribe first penetrated the top material — aluminum — and then the scribe cut the bottom material — steel. The steel was displaced into the upper material to produce a characteristic hook feature. Lap welds were shear tested, and their fracture paths were studied. Welding parameters affected the welding features including hook height, which turned out to be highly related to fracture position. Therefore,more » in this paper, the relationships among welding parameters, hook height, joint strength and fracture position are presented. In addition, influence of zinc coating on joint strength was also studied. Keywords: friction stir scribe technology; dissimilar material welding; zinc coating; hook height; joint strength; fracture position« less

Larval body patterning and apical organs are conserved in animal evolution

PubMed Central

2014-01-01

Background Planktonic ciliated larvae are characteristic for the life cycle of marine invertebrates. Their most prominent feature is the apical organ harboring sensory cells and neurons of largely undetermined function. An elucidation of the relationships between various forms of primary larvae and apical organs is key to understanding the evolution of animal life cycles. These relationships have remained enigmatic due to the scarcity of comparative molecular data. Results To compare apical organs and larval body patterning, we have studied regionalization of the episphere, the upper hemisphere of the trochophore larva of the marine annelid Platynereis dumerilii. We examined the spatial distribution of transcription factors and of Wnt signaling components previously implicated in anterior neural development. Pharmacological activation of Wnt signaling with Gsk3β antagonists abolishes expression of apical markers, consistent with a repressive role of Wnt signaling in the specification of apical tissue. We refer to this Wnt-sensitive, six3- and foxq2-expressing part of the episphere as the ‘apical plate’. We also unraveled a molecular signature of the apical organ - devoid of six3 but expressing foxj, irx, nkx3 and hox - that is shared with other marine phyla including cnidarians. Finally, we characterized the cell types that form part of the apical organ by profiling by image registration, which allows parallel expression profiling of multiple cells. Besides the hox-expressing apical tuft cells, this revealed the presence of putative light- and mechanosensory as well as multiple peptidergic cell types that we compared to apical organ cell types of other animal phyla. Conclusions The similar formation of a six3+, foxq2+ apical plate, sensitive to Wnt activity and with an apical tuft in its six3-free center, is most parsimoniously explained by evolutionary conservation. We propose that a simple apical organ - comprising an apical tuft and a basal plexus innervated by sensory-neurosecretory apical plate cells - was present in the last common ancestors of cnidarians and bilaterians. One of its ancient functions would have been the control of metamorphosis. Various types of apical plate cells would then have subsequently been added to the apical organ in the divergent bilaterian lineages. Our findings support an ancient and common origin of primary ciliated larvae. PMID:24476105

Revascularization and periapical repair after endodontic treatment using apical negative pressure irrigation versus conventional irrigation plus triantibiotic intracanal dressing in dogs' teeth with apical periodontitis.

PubMed

da Silva, Lea Assed Bezerra; Nelson-Filho, Paulo; da Silva, Raquel Assed Bezerra; Flores, Daniel Silva Herzog; Heilborn, Carlos; Johnson, James D; Cohenca, Nestor

2010-05-01

The objective of this study was to evaluate in vivo the revascularization and the apical and periapical repair after endodontic treatment using 2 techniques for root canal disinfection (apical negative pressure irrigation versus apical positive pressure irrigation plus triantibiotic intracanal dressing) in immature dogs' teeth with apical periodontitis. Two test groups of canals with experimentally induced apical periodontitis were evaluated according to the disinfection technique: Group 1, apical negative pressure irrigation (EndoVac system), and Group 2, apical positive pressure irrigation (conventional irrigation) plus triantibiotic intracanal dressing. In Group 3 (positive control), periapical lesions were induced, but no endodontic treatment was done. Group 4 (negative control) was composed of sound teeth. The animals were killed after 90 days and the maxillas and mandibles were subjected to histological processing. The sections were stained with hematoxylin and eosin and Mallory Trichrome and examined under light microscopy. A description of the apical and periapical features was done and scores were attributed to the following histopathological parameters: newly formed mineralized apical tissue, periapical inflammatory infiltrate, apical periodontal ligament thickness, dentin resorption, and bone tissue resorption. Intergroup comparisons were done by the Kruskal-Wallis and Dunn's tests (alpha = 0.05). Although statistically significant difference was found only for the inflammatory infiltrate (P < .05), Group 1 presented more exuberant mineralized formations, more structured apical and periapical connective tissue, and a more advanced repair process than Group 2. From the histological observations, sodium hypochlorite irrigation with the EndoVac system can be considered as a promising disinfection protocol in immature teeth with apical periodontitis, suggesting that the use of intracanal antibiotics might not be necessary. Copyright (c) 2010 Mosby, Inc. All rights reserved.

Apical root canal microbiota as determined by reverse-capture checkerboard analysis of cryogenically ground root samples from teeth with apical periodontitis.

PubMed

Rôças, Isabela N; Alves, Flávio R F; Santos, Adriana L; Rosado, Alexandre S; Siqueira, José F

2010-10-01

Bacteria located in the apical root canal system potentially participate in the pathogenesis of apical periodontitis. Detection and identification of apical bacteria can be compromised because of limitations in conventional sampling and identification procedures. This study identified several bacterial taxa in the apical and middle/coronal segments of primarily infected root canal system by using pulverized root segments and a culture-independent molecular method. Seventeen extracted teeth with attached apical periodontitis lesions were sectioned to obtain 2 root fragments (apical and middle/coronal segments). Root fragments were cryogenically ground, and DNA was extracted from samples. After multiple displacement amplification, DNA from samples was used as template in a reverse-capture checkerboard hybridization assay targeting 28 bacterial taxa. Bacterial DNA was detected in all samples. The most prevalent taxa in the apical root canal system were Olsenella uli (76.5%), Prevotella baroniae (71%), Porphyromonas endodontalis (65%), Fusobacterium nucleatum (53%), and Tannerella forsythia (47%). O. uli, P. endodontalis, and Propionibacterium acnes were as frequently detected in apical samples as they were in middle/coronal samples. P. baroniae, T. forsythia, and F. nucleatum were found more frequently in the apical part of the canal as compared with matched coronal segments. Streptococcus species were more prevalent in middle/coronal samples. The median and mean of shared bacterial taxa between matched apical and middle/coronal segments were 27% and 41%, respectively. Several candidate endodontic pathogens were very prevalent in the apical root canal system. The apical microbiota was usually complex and differed in species composition when compared with the microbiota of middle/coronal samples from the same tooth. Copyright © 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Smear Layer Outcome on Healing

DTIC Science & Technology

2015-07-31

apical tissues, symptomatic apical periodontitis , asymptomatic apical periodontitis , chronic apical abscess or condensing osteomyelitis - Presence...percha • Patients presenting with periodontal disease or acute apical abscess ·Patients currently taking antibiotics If a patient expressed an... periodontitis : A randomized clinical trial. Joumal of Endodontics, 33, 1145-48. 23. Moss D, Allemang J, Johnson J. (2001). Philosophies and Practices

Apical targeting of the formin Diaphanous in Drosophila tubular epithelia

PubMed Central

Rousso, Tal; Shewan, Annette M; Mostov, Keith E; Schejter, Eyal D; Shilo, Ben-Zion

2013-01-01

Apical secretion from epithelial tubes of the Drosophila embryo is mediated by apical F-actin cables generated by the formin-family protein Diaphanous (Dia). Apical localization and activity of Dia are at the core of restricting F-actin formation to the correct membrane domain. Here we identify the mechanisms that target Dia to the apical surface. PI(4,5)P2 levels at the apical membrane regulate Dia localization in both the MDCK cyst model and in Drosophila tubular epithelia. An N-terminal basic domain of Dia is crucial for apical localization, implying direct binding to PI(4,5)P2. Dia apical targeting also depends on binding to Rho1, which is critical for activation-induced conformational change, as well as physically anchoring Dia to the apical membrane. We demonstrate that binding to Rho1 facilitates interaction with PI(4,5)P2 at the plane of the membrane. Together these cues ensure efficient and distinct restriction of Dia to the apical membrane. DOI: http://dx.doi.org/10.7554/eLife.00666.001 PMID:23853710

RhoA regulates actin network dynamics during apical surface emergence in multiciliated epithelial cells

PubMed Central

Sedzinski, Jakub; Hannezo, Edouard; Tu, Fan; Biro, Maté

2017-01-01

ABSTRACT Homeostatic replacement of epithelial cells from basal precursors is a multistep process involving progenitor cell specification, radial intercalation and, finally, apical surface emergence. Recent data demonstrate that actin-based pushing under the control of the formin protein Fmn1 drives apical emergence in nascent multiciliated epithelial cells (MCCs), but little else is known about this actin network or the control of Fmn1. Here, we explore the role of the small GTPase RhoA in MCC apical emergence. Disruption of RhoA function reduced the rate of apical surface expansion and decreased the final size of the apical domain. Analysis of cell shapes suggests that RhoA alters the balance of forces exerted on the MCC apical surface. Finally, quantitative time-lapse imaging and fluorescence recovery after photobleaching studies argue that RhoA works in concert with Fmn1 to control assembly of the specialized apical actin network in MCCs. These data provide new molecular insights into epithelial apical surface assembly and could also shed light on mechanisms of apical lumen formation. PMID:28089989

RhoA regulates actin network dynamics during apical surface emergence in multiciliated epithelial cells.

PubMed

Sedzinski, Jakub; Hannezo, Edouard; Tu, Fan; Biro, Maté; Wallingford, John B

2017-01-15

Homeostatic replacement of epithelial cells from basal precursors is a multistep process involving progenitor cell specification, radial intercalation and, finally, apical surface emergence. Recent data demonstrate that actin-based pushing under the control of the formin protein Fmn1 drives apical emergence in nascent multiciliated epithelial cells (MCCs), but little else is known about this actin network or the control of Fmn1. Here, we explore the role of the small GTPase RhoA in MCC apical emergence. Disruption of RhoA function reduced the rate of apical surface expansion and decreased the final size of the apical domain. Analysis of cell shapes suggests that RhoA alters the balance of forces exerted on the MCC apical surface. Finally, quantitative time-lapse imaging and fluorescence recovery after photobleaching studies argue that RhoA works in concert with Fmn1 to control assembly of the specialized apical actin network in MCCs. These data provide new molecular insights into epithelial apical surface assembly and could also shed light on mechanisms of apical lumen formation. © 2017. Published by The Company of Biologists Ltd.

Definitions of apical vaginal support loss: a systematic review.

PubMed

Meister, Melanie R L; Sutcliffe, Siobhan; Lowder, Jerry L

2017-03-01

We sought to identify and summarize definitions of apical support loss utilized for inclusion, success, and failure in surgical trials for treatment of apical vaginal prolapse. Pelvic organ prolapse is a common condition affecting more than 3 million women in the US, and the prevalence is increasing. Prolapse may occur in the anterior compartment, posterior compartment or at the apex. Apical support is considered paramount to overall female pelvic organ support, yet apical support loss is often underrecognized and there are no guidelines for when an apical support procedure should be performed or incorporated into a procedure designed to address prolapse. A systematic literature search was performed in 8 search engines: PubMed 1946-, Embase 1947-, Cochrane Database of Systematic Reviews, Cochrane Database of Abstracts of Review Effects, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, Proquest Dissertations and Theses, and FirstSearch Proceedings, using key words for apical pelvic organ prolapse and apical suspension procedures through April 2016. Searches were limited to human beings using human filters and articles published in English. Study authors (M.R.L.M., J.L.L.) independently reviewed publications for inclusion based on predefined variables. Articles were eligible for inclusion if they satisfied any of the following criteria: (1) apical support loss was an inclusion criterion in the original study, (2) apical support loss was a surgical indication, or (3) an apical support procedure was performed as part of the primary surgery. A total of 4469 publications were identified. After review, 35 articles were included in the analysis. Prolapse-related inclusion criteria were: (1) apical prolapse (n = 20, 57.1%); (2) overall prolapse (n = 8, 22.8%); or (3) both (n = 6, 17.1%). Definitions of apical prolapse (relative to the hymen) included: (1) apical prolapse >-1 cm (n = 13, 50.0%); (2) apical prolapse >+1 cm (n = 7, 26.9%); (3) apical prolapse >50% of total vaginal length (-[total vaginal length/2]) (n = 4, 15.4%); and (4) cervix/apex >0 cm (n = 2, 7.7%). Sixteen of the 35 studies (45.7%) required the presence of symptoms for inclusion. A measurement of the apical compartment (relative to the hymen) was used as a measure of surgical success or failure in 17 (48.6%) studies. Definitions for surgical success included: (1) prolapse stage >2 in each compartment (n = 5, 29.4%); (2) prolapse >-[total vaginal length/2] (n = 2, 11.8%); (3) apical support >-[total vaginal length/3] (n = 1, 5.9%); (4) absence of prolapse beyond the hymen (n = 1, 5.9%); and (5) point C at ≥-5 cm (n = 2, 11.8%). Surgical failure was defined as: (1) apical prolapse ≥0 cm (n = 2, 11.8%); (2) apical prolapse ≥-1 cm (n = 2, 11.8%); (3) apical prolapse >-[total vaginal length/2] (n = 3, 17.6%); and (4) recurrent apical prolapse surgery (n = 1, 5.9%). Ten (28.6%) of the 35 studies also included symptomatic outcomes in the definition of success or failure. Among randomized, controlled surgical trials designed to address apical vaginal support loss, definitions of clinically significant apical prolapse for study inclusion and surgical success or failure are either highly variable or absent. These findings provide limited evidence of consensus and little insight into current expert opinion. Copyright © 2016 Elsevier Inc. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Iguchi, Toshihiro, E-mail: iguchi@ba2.so-net.ne.jp; Hiraki, Takao, E-mail: takaoh@tc4.so-net.ne.jp; Gobara, Hideo, E-mail: gobara@cc.okayama-u.ac.jp

PurposeThe aim of the study was to retrospectively evaluate simultaneous multiple hook wire placement outcomes before video-assisted thoracoscopic surgery (VATS).Materials and MethodsThirty-eight procedures were performed on 35 patients (13 men and 22 women; mean age, 59.9 years) with 80 lung lesions (mean diameter 7.9 mm) who underwent simultaneous multiple hook wire placements for preoperative localizations. The primary endpoints were technical success, complications, procedure duration, and VATS outcome; secondary endpoints included comparisons between technical success rates, complication rates, and procedure durations of the 238 single-placement procedures performed. Complications were also evaluated.ResultsIn 35 procedures including 74 lesions, multiple hook wire placements were technically successful;more » in the remaining three procedures, the second target placement was aborted because of massive pneumothorax after the first placement. Although complications occurred in 34 procedures, no grade 3 or above adverse event was observed. The mean procedure duration was 36.4 ± 11.8 min. Three hook wires dislodged during patient transport to the surgical suite. Seventy-four successfully marked lesions were resected. Six lesions without hook wires were successfully resected after detection by palpation with an additional mini-thoracotomy or using subtle pleural changes as a guide. The complication rates and procedure durations of multiple-placement procedures were significantly higher (P = 0.04) and longer (P < 0.001) than those in the single-placement group, respectively, while the technical success rate was not significantly different (P = 0.051).ConclusionsSimultaneous multiple hook wire placements before VATS were clinically feasible, but increased the complication rate and lengthened the procedure time.« less

Insights into the Functions of M-T Hook Structure in HIV Fusion Inhibitor Using Molecular Modeling.

PubMed

Tan, Jianjun; Yuan, Hongling; Li, Chunhua; Zhang, Xiaoyi; Wang, Cunxin

2016-04-01

HIV-1 membrane fusion plays an important role in the process that HIV-1 entries host cells. As a treatment strategy targeting HIV-1 entry process, fusion inhibitors have been proposed. Nevertheless, development of a short peptide possessing high anti-HIV potency is considered a daunting challenge. He et al. found that two residues, Met626 and Thr627, located the upstream of the C-terminal heptad repeat of the gp41, formed a unique hook-like structure (M-T hook) that can dramatically improve the binding stability and anti-HIV activity of the inhibitors. In this work, we explored the molecular mechanism why M-T hook structure could improve the anti-HIV activity of inhibitors. Firstly, molecular dynamic simulation was used to obtain information on the time evolution between gp41 and ligands. Secondly, based on the simulations, molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) and molecular mechanics Generalized Born surface area (MM-GBSA) methods were used to calculate the binding free energies. The binding free energy of the ligand with M-T hook was considerably higher than the other without M-T. Further studies showed that the hydrophobic interactions made the dominant contribution to the binding free energy. The numbers of Hydrogen bonds between gp41 and the ligand with M-T hook structure were more than the other. These findings should provide insights into the inhibition mechanism of the short peptide fusion inhibitors and be useful for the rational design of novel fusion inhibitors in the future. Copyright © 2016 Elsevier Ltd. All rights reserved.

Comparison of concentric needle versus hooked-wire electrodes in the canine larynx.

PubMed

Jaffe, D M; Solomon, N P; Robinson, R A; Hoffman, H T; Luschei, E S

1998-05-01

The use of a specific electrode type in laryngeal electromyography has not been standardized. Laryngeal electromyography is usually performed with hooked-wire electrodes or concentric needle electrodes. Hooked-wire electrodes have the advantage of allowing laryngeal movement with ease and comfort, whereas the concentric needle electrodes have benefits from a technical aspect and may be advanced, withdrawn, or redirected during attempts to appropriately place the electrode. This study examines whether hooked-wire electrodes permit more stable recordings than standard concentric needle electrodes at rest and after large-scale movements of the larynx and surrounding structures. A histologic comparison of tissue injury resulting from placement and removal of the two electrode types is also made by evaluation of the vocal folds. Electrodes were percutaneously placed into the thyroarytenoid muscles of 10 adult canines. Amplitude of electromyographic activity was measured and compared during vagal stimulation before and after large-scale laryngeal movements. Signal consistency over time was examined. Animals were killed and vocal fold injury was graded and compared histologically. Waveform morphology did not consistently differ between electrode types. The variability of electromyographic amplitude was greater for the hooked-wire electrode (p < 0.05), whereas the mean amplitude measures before and after large-scale laryngeal movements did not differ (p > 0.05). Inflammatory responses and hematoma formation were also similar. Waveform morphology of electromyographic signals registered from both electrode types show similar complex action potentials. There is no difference between the hooked-wire electrode and the concentric needle electrode in terms of electrode stability or vocal fold injury in the thyroarytenoid muscle after large-scale laryngeal movements.

Diagnosis of apical hypertrophic cardiomyopathy: T-wave inversion and relative but not absolute apical left ventricular hypertrophy☆

PubMed Central

Flett, Andrew S.; Maestrini, Viviana; Milliken, Don; Fontana, Mariana; Treibel, Thomas A.; Harb, Rami; Sado, Daniel M.; Quarta, Giovanni; Herrey, Anna; Sneddon, James; Elliott, Perry; McKenna, William; Moon, James C.

2015-01-01

Background Diagnosis of apical HCM utilizes conventional wall thickness criteria. The normal left ventricular wall thins towards the apex such that normal values are lower in the apical versus the basal segments. The impact of this on the diagnosis of apical hypertrophic cardiomyopathy has not been evaluated. Methods We performed a retrospective review of 2662 consecutive CMR referrals, of which 75 patients were identified in whom there was abnormal T-wave inversion on ECG and a clinical suspicion of hypertrophic cardiomyopathy. These were retrospectively analyzed for imaging features consistent with cardiomyopathy, specifically: relative apical hypertrophy, left atrial dilatation, scar, apical cavity obliteration or apical aneurysm. For comparison, the same evaluation was performed in 60 healthy volunteers and 50 hypertensive patients. Results Of the 75 patients, 48 met conventional HCM diagnostic criteria and went on to act as another comparator group. Twenty-seven did not meet criteria for HCM and of these 5 had no relative apical hypertrophy and were not analyzed further. The remaining 22 patients had relative apical thickening with an apical:basal wall thickness ratio > 1 and a higher prevalence of features consistent with a cardiomyopathy than in the control groups with 54% having 2 or more of the 4 features. No individual in the healthy volunteer group had more than one feature and no hypertension patient had more than 2. Conclusion A cohort of individuals exist with T wave inversion, relative apical hypertrophy and additional imaging features of HCM suggesting an apical HCM phenotype not captured by existing diagnostic criteria. PMID:25666123

Apical stress distribution under vertical compaction of gutta-percha and occlusal loads in canals with varying apical sizes: a three-dimensional finite element analysis.

PubMed

Yuan, K; Niu, C; Xie, Q; Jiang, W; Gao, L; Ma, R; Huang, Z

2018-02-01

To investigate and compare the effects of two apical canal instrumentation protocols on apical stress distribution at the root apex under vertical compaction of gutta-percha and occlusal loads using finite element analysis. Three finite element analysis models of a mandibular first premolar were reconstructed: an original canal model, a size 35, .04 taper apical canal enlargement model and a Lightspeed size 60 apical canal enlargement model. A 15 N compaction force was applied vertically to the gutta-percha 5 mm from the apex. A 175 N occlusal load in two directions (vertical and 45° to the longitudinal axis of the tooth) was simulated. Stresses in the apical 2 mm of the root were calculated and compared among the three models. Under vertical compaction, stresses in the apical canal instrumented by Lightspeed size 60 (maximal 3.3 MPa) were higher than that of the size 35, .04 taper model (maximal 1.3 MPa). In the case of the two occlusal forces, the Lightspeed size 60 apical enlargement was associated with the greatest stress distribution in the apical region. The greatest stress and the most obvious stress difference between the models appeared at the tip of the root when occlusal and vertical compaction loads were applied. Apical enlargement caused stress distribution changes in the apical region of roots. The larger apical size led to higher stress concentration at the root apex. © 2017 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Incidence of apical crack formation and propagation during removal of root canal filling materials with different engine driven nickel-titanium instruments.

PubMed

Özyürek, Taha; Tek, Vildan; Yılmaz, Koray; Uslu, Gülşah

2017-11-01

To determine the incidence of crack formation and propagation in apical root dentin after retreatment procedures performed using ProTaper Universal Retreatment (PTR), Mtwo-R, ProTaper Next (PTN), and Twisted File Adaptive (TFA) systems. The study consisted of 120 extracted mandibular premolars. One millimeter from the apex of each tooth was ground perpendicular to the long axis of the tooth, and the apical surface was polished. Twenty teeth served as the negative control group. One hundred teeth were prepared, obturated, and then divided into 5 retreatment groups. The retreatment procedures were performed using the following files: PTR, Mtwo-R, PTN, TFA, and hand files. After filling material removal, apical enlargement was done using apical size 0.50 mm ProTaper Universal (PTU), Mtwo, PTN, TFA, and hand files. Digital images of the apical root surfaces were recorded before preparation, after preparation, after obturation, after filling removal, and after apical enlargement using a stereomicroscope. The images were then inspected for the presence of new apical cracks and crack propagation. Data were analyzed with χ 2 tests using SPSS 21.0 software. New cracks and crack propagation occurred in all the experimental groups during the retreatment process. Nickel-titanium rotary file systems caused significantly more apical crack formation and propagation than the hand files. The PTU system caused significantly more apical cracks than the other groups after the apical enlargement stage. This study showed that retreatment procedures and apical enlargement after the use of retreatment files can cause crack formation and propagation in apical dentin.

Covariant Formulation of Hooke's Law.

ERIC Educational Resources Information Center

Gron, O.

1981-01-01

Introducing a four-vector strain and a four-force stress, Hooke's law is written as a four-vector equation. This formulation is shown to clarify seemingly paradoxical results in connection with uniformly accelerated motion, and rotational motion with angular acceleration. (Author/JN)

Are we sinking Sandy Hook? Possible impacts of groundwater extraction to sea-level change

NASA Astrophysics Data System (ADS)

Johnson, C. S.; Fan, Y.; Miller, K. G.; Browning, J. V.

2017-12-01

The tide gauge at Sandy Hook, NJ, a spit of sand extending 8 km into Raritan Bay of New York and New Jersey, recorded a 20th century rate of relative sea-level (RSL) rise of 4.0±0.5 mm/yr, significantly higher than the 1.4±0.2 mm/yr rate of global mean sea-level rise for the twentieth century. The Battery, NY tide gauge, located atop crystalline bedrock 26 km to the northwest, recorded a 20th century rate of RSL rise of 3.0±0.3 mm/yr and reflects the regional rate of RSL rise. After global and regional effects are removed from the rate of RSL rise at Sandy Hook, the remaining 0.9±0.5 mm/yr is due to local effects, autocompaction and groundwater extraction induced compaction, within the unconsolidated Cretaceous to recent sediments underlying Sandy Hook. Our previous work showed that 0.13 mm/yr (90% CI 0.01-0.34 mm/yr) is due to autocompaction of young (≤13,350 cal yrs BP), highly compressible, Quaternary sediments underlying Sandy Hook. The remaining 0.8 mm/yr (90% CI 0.3-1.2 mm/yr) is hypothesized to be due to regional and local groundwater extraction. Previous studies have shown that Sandy Hook is within the cone of depression for Monmouth County, NJ. Historical records indicate that pumping for Ft. Hancock, a military installation on Sandy Hook, depleted some shallow aquifers as early as 1905. Visual MODFLOW was used to model the northern portion of the New Jersey coastal plain. Well logs from the northern New Jersey coastal plain were compiled and interpreted to refine subsurface geometries and build the model grid. Well permits provided modern locations and rates of groundwater extraction. 1,794 observation wells were used to calibrate the model. We present model results simulating the change in regional and local groundwater flow and hydraulic pressures from pre-development ( 1880) to present. The pressure changes were then used to calculate the potential changes in thickness of each of the stratigraphic units underneath Sandy Hook between 1880 and present. The resulting average rate of groundwater extraction induced compaction is between 0.2 and 4.3 mm/yr. Better constraints on stratigraphy, pumping rates, and improved model boundaries are being used to narrow this range.

Does apical root resection in endodontic microsurgery jeopardize the prosthodontic prognosis?

PubMed Central

Cho, Sin-Yeon

2013-01-01

Apical surgery cuts off the apical root and the crown-to-root ratio becomes unfavorable. Crown-to-root ratio has been applied to periodontally compromised teeth. Apical root resection is a different matter from periodontal bone loss. The purpose of this paper is to review the validity of crown-to-root ratio in the apically resected teeth. Most roots have conical shape and the root surface area of coronal part is wider than apical part of the same length. Therefore loss of alveolar bone support from apical resection is much less than its linear length.The maximum stress from mastication concentrates on the cervical area and the minimum stress was found on the apical 1/3 area. Therefore apical root resection is not so harmful as periodontal bone loss. Osteotomy for apical resection reduces longitudinal width of the buccal bone and increases the risk of endo-perio communication which leads to failure. Endodontic microsurgery is able to realize 0 degree or shallow bevel and precise length of root resection, and minimize the longitudinal width of osteotomy. The crown-to-root ratio is not valid in evaluating the prosthodontic prognosis of the apically resected teeth. Accurate execution of endodontic microsurgery to preserve the buccal bone is essential to avoid endo-perio communication. PMID:23741707

Apical sorting of lysoGPI-anchored proteins occurs independent of association with detergent-resistant membranes but dependent on their N-glycosylation.

PubMed

Castillon, Guillaume Alain; Michon, Laetitia; Watanabe, Reika

2013-06-01

Most glycosylphosphatidylinositol-anchored proteins (GPI-APs) are located at the apical surface of epithelial cells. The apical delivery of GPI-APs is believed to result from their association with lipid rafts. We find that overexpression of C-terminally tagged PGAP3 caused predominant production of lysoGPI-APs, an intermediate precursor in the GPI lipid remodeling process in Madin-Darby canine kidney cells. In these cells, produced lysoGPI-APs are not incorporated into detergent-resistant membranes (DRMs) but still are delivered apically, suggesting that GPI-AP association with DRMs is not necessary for apical targeting. In contrast, apical transport of both fully remodeled and lyso forms of GPI-APs is dependent on N-glycosylation, confirming a general role of N-glycans in apical protein transport. We also find that depletion of cholesterol causes apical-to-basolateral retargeting not only of fully remodeled GPI-APs, but also of lysoGPI-APs, as well as endogenous soluble and transmembrane proteins that would normally be targeted to the apical membrane. These findings confirm the essential role for cholesterol in the apical protein targeting and further demonstrate that the mechanism of cholesterol-dependent apical sorting is not related to DRM association of GPI-APs.

An Apical MRCK-driven Morphogenetic Pathway Controls Epithelial Polarity

PubMed Central

Zihni, Ceniz; Vlassaks, Evi; Terry, Stephen; Carlton, Jeremy; Leung, Thomas King Chor; Olson, Michael; Pichaud, Franck; Balda, Maria Susana; Matter, Karl

2017-01-01

Polarized epithelia develop distinct cell surface domains, with the apical membrane acquiring characteristic morphological features such as microvilli. Cell polarization is driven by polarity determinants including the evolutionarily conserved partitioning defective (PAR) proteins that are separated into distinct cortical domains. PAR protein segregation is thought to be a consequence of asymmetric actomyosin contractions. The mechanism of activation of apically polarized actomyosin contractility is unknown. Here we show that the Cdc42 effector MRCK activates Myosin-II at the apical pole to segregate aPKC-Par6 from junctional Par3, defining the apical domain. Apically polarized MRCK-activated actomyosin contractility is reinforced by cooperation with aPKC-Par6 downregulating antagonistic RhoA-driven junctional actomyosin contractility, and drives polarization of cytosolic brush border determinants and apical morphogenesis. MRCK-activated polarized actomyosin contractility is required for apical differentiation and morphogenesis in vertebrate epithelia and Drosophila photoreceptors. Our results identify an apical origin of actomyosin-driven morphogenesis that couples cytoskeletal reorganization to PAR polarity signalling. PMID:28825699

Apical ammonium inhibition of cAMP-stimulated secretion in T84 cells is bicarbonate dependent.

PubMed

Worrell, Roger T; Best, Alison; Crawford, Oscar R; Xu, Jie; Soleimani, Manoocher; Matthews, Jeffrey B

2005-10-01

Normal human colonic luminal (NH(4)(+)) concentration ([NH(4)(+)]) ranges from approximately 10 to 100 mM. However, the nature of the effects of NH(4)(+) on transport, as well as NH(4)(+) transport itself, in colonic epithelium is poorly understood. We elucidate here the effects of apical NH(4)(+) on cAMP-stimulated Cl(-) secretion in colonic T84 cells. In HEPES-buffered solutions, 10 mM apical NH(4)(+) had no significant effect on cAMP-stimulated current. In contrast, 10 mM apical NH(4)(+) reduced current within 5 min to 61 +/- 4% in the presence of 25 mM HCO(3)(-). Current inhibition was not simply due to an increase in extracellular K(+)-like cations, in that the current magnitude was 95 +/- 5% with 10 mM apical K(+) and 46 +/- 3% with 10 mM apical NH(4)(+) relative to that with 5 mM apical K(+). We previously demonstrated that inhibition of Cl(-) secretion by basolateral NH(4)(+) occurs in HCO(3)(-)-free conditions and exhibits anomalous mole fraction behavior. In contrast, apical NH(4)(+) inhibition of current in HCO(3)(-) buffer did not show anomalous mole fraction behavior and followed the absolute [NH(4)(+)] in K(+)-NH(4)(+) mixtures, where K(+) concentration + [NH(4)(+)] = 10 mM. The apical NH(4)(+) inhibitory effect was not prevented by 100 microM methazolamide, suggesting no role for apical carbonic anhydrase. However, apical NH(4)(+) inhibition of current was prevented by 10 min of pretreatment of the apical surface with 500 microM DIDS, 100 microM 4,4'-dinitrostilbene-2,2'-disulfonic acid (DNDS), or 25 microM niflumic acid, suggesting a role for NH(4)(+) action through an apical anion exchanger. mRNA and protein for the apical anion exchangers SLC26A3 [downregulated in adenoma (DRA)] and SLC26A6 [putative anion transporter (PAT1)] were detected in T84 cells by RT-PCR and Northern and Western blots. DRA and PAT1 appear to associate with CFTR in the apical membrane. We conclude that the HCO(3)(-) dependence of apical NH(4)(+) inhibition of secretion is due to the action of NH(4)(+) on an apical anion exchanger.

Bone resorptive activity in symptomatic and asymptomatic apical lesions of endodontic origin.

PubMed

Salinas-Muñoz, M; Garrido-Flores, M; Baeza, M; Huamán-Chipana, P; García-Sesnich, J; Bologna, R; Vernal, R; Hernández, M

2017-11-01

The aim of this study is to assess the levels and diagnostic accuracy of a set of bone resorption biomarkers, including TRAP-5, RANKL, and OPG in symptomatic and asymptomatic apical lesions and controls. Apical tissues from symptomatic and asymptomatic apical periodontitis patients and periodontal ligaments from healthy teeth extracted for orthodontic reasons were processed for tissue homogenization and the levels of TRAP-5, RANKL, and OPG were determined by multiplex assay. Marker levels were analyzed by Kruskal Wallis test, and diagnostic accuracy was analyzed with ROC curves. Higher levels of RANKL, OPG, and RANKL/OPG ratio were determined in both types of apical lesions compared to healthy periodontal ligament, whereas higher TRAP-5 levels were found only in symptomatic apical lesions (p < 0.05). OPG, RANKL, and RANKL/OPG ratio showed diagnostic potential to identify apical lesions versus healthy controls (AUC = 0.69, p < 0.05); while TRAP-5 showed a potential to discriminate symptomatic versus asymptomatic apical periodontitis (AUC = 0.71, p < 0.05) and healthy controls (AUC = 0.83, p < 0.05). Apical lesions showed higher RANKL and OPG levels than healthy tissues. TRAP-5 levels were the highest in symptomatic apical lesions, suggesting that these represent a progressive state, and showed diagnostic potential. Clinically symptomatic apical periodontitis might represent biologically progressive apical lesions based on TRAP5 levels. TRAP5 has diagnostic potential to identify these lesions, representing a candidate prognostic biomarker.

Unwanted Workplace Experiences DEOCS 4.1 Construct Validity Summary

DTIC Science & Technology

2017-08-01

range from repeatedly asking you out for coffee to asking you for sex or a ’hook-up’. e. Intentionally touch you in a sexual way when you did not...coffee to asking you for sex or a ’hook-up’. 1.98 0.15 -6.25 37.04 e. Intentionally touch you in a sexual way when you did not want them to...coffee to asking you for sex or a ’hook-up’. 7.85 0.34 .62 0.78 e. Intentionally touch you in a sexual way when you did not want them to? This could

Anterior cruciate ligament rupture secondary to a 'heel hook': a dangerous martial arts technique.

PubMed

Baker, Joseph F; Devitt, Brian M; Moran, Ray

2010-01-01

The 'heel hook' is a type of knee lock used in some forms of martial arts to stress the knee and cause opponent to concede defeat. While the knee is in a flexed and valgus disposition, an internal rotation force is applied to the tibia. Reports are lacking on serious knee trauma as a result of this technique. We report the case of a 32-year-old Mixed Martial Arts exponent who sustained complete anterior cruciate ligament rupture and an medial collateral ligament injury from the use of a 'heel hook'.

Attachment device

NASA Technical Reports Server (NTRS)

Zaguli, Ronald J. (Inventor)

1994-01-01

An apparatus is disclosed for capturing and holding a rod, bar or similar member; the apparatus having in one aspect a body member with a recess therein and a hook extending from the body member, the hook and recess defining a capture envelope for receiving and confining the rod, etc. In one aspect such an apparatus is disclosed in which the hook is movable with respect to the body member to vary the size of the capture envelope, both to initially facilitate emplacement of the apparatus about the rod, etc., and then to provide for tightening of the apparatus about the rod, etc., if desired.

Automation Hooks Architecture for Flexible Test Orchestration - Concept Development and Validation

NASA Technical Reports Server (NTRS)

Lansdowne, C. A.; Maclean, John R.; Winton, Chris; McCartney, Pat

2011-01-01

The Automation Hooks Architecture Trade Study for Flexible Test Orchestration sought a standardized data-driven alternative to conventional automated test programming interfaces. The study recommended composing the interface using multicast DNS (mDNS/SD) service discovery, Representational State Transfer (Restful) Web Services, and Automatic Test Markup Language (ATML). We describe additional efforts to rapidly mature the Automation Hooks Architecture candidate interface definition by validating it in a broad spectrum of applications. These activities have allowed us to further refine our concepts and provide observations directed toward objectives of economy, scalability, versatility, performance, severability, maintainability, scriptability and others.

Bioinspired Superdurable Pestle‐Loop Mechanical Interlocker with Tunable Peeling Force, Strong Shear Adhesion, and Low Noise

PubMed Central

Jiao, Junrong; Zhang, Feilong; Jiao, Tian; Gu, Zhen

2018-01-01

Abstract Velcro, the most typical hook‐loop interlocker, often suffers from undesirable deformation, breaking, and noise because of the structure of the hook. Inspired by the arrester system of dragonfly, a new mechanical interlocker with a nylon pestle instead of the traditional hook is developed. The pestle‐loop mechanical interlocker shows a tunable peeling force from 0.4 ± 0.14 to 6.5 ± 0.72 N and the shear adhesion force of pestle‐loop mechanical interlocker is about twice as much as that of velcro. The pestle tape can be separated and fastened with the loop tape up to 30 000 cycles while keeping the original adhesive force and the pestle structure. In comparison, only after 4000 cycles most hooks of the commercial velcro are deformed and even broken, completely losing their adhesive function and their hook structure. These experimental results are further supported by finite element simulitions—the base of pestle mainly bears the separation‐caused strain while the middle of hook does. Notably, the sound volume during the separation of pestle‐loop mechanical interlocker is merely 49 ± 7.4 dB, much lower than 70 ± 3.5 dB produced by the velcro. PMID:29721425

Extremely high myoglobin plasma concentrations producing hook effect in a critically ill patient.

PubMed

Kurt-Mangold, Michelle; Drees, Denny; Krasowski, Matthew D

2012-12-24

A 21-year old female suffered a cardiac arrest after a one week history of viral illness later shown to be caused by influenza B. The patient required extended cardiopulmonary resuscitation and had further complications including compartment syndrome. Plasma myoglobin concentration was measured using the Roche Diagnostics electrochemiluminescent myoglobin assay. The myoglobin concentration was 205,590 μg/l in an undiluted specimen, consistent with severe rhabdomyolysis. Subsequent myoglobin concentrations measured two days later showed dramatic decreases to approximately 1000 μg/l, raising suspicion of a hook effect. Dilution and re-analysis of the specimens revealed that the actual myoglobin concentrations were >395,000 μg/l, with one specimen possessing an estimated myoglobin concentration of >600,000 μg/l. Interestingly, three specimens from this patient did not show evidence of hook effect, with undiluted specimens producing myoglobin concentrations as high as 284,000 μg/l. Retrospective analysis of myoglobin results over an 8-year period did not reveal other cases with suspicion of hook effect. The case patient had the highest myoglobin concentrations out of 7301 specimens. This case illustrates that while the Roche myoglobin assay has a very wide dynamic range, hook effect can occur with extremely high concentrations of plasma myoglobin. Copyright © 2012 Elsevier B.V. All rights reserved.

Stress induced by hooking, net towing, elevated sea water temperature and air in sablefish: Lack of concordance between mortality and physiological measures of stress

USGS Publications Warehouse

Davis, M.W.; Olla, B.L.; Schreck, C.B.

2001-01-01

In a series of laboratory studies designed to simulate bycatch processes, sablefish Anoplopoma fimbria were either hooked for up to 24 h or towed in a net for 4 h and then subjected to an abrupt transfer to elevated sea water temperature and air. Mortality did not result from hooking or net towing followed by exposure to air, but increased for both capture methods as fish were exposed to elevated temperatures, reflecting the magnifying effect of elevated temperature on mortality. Hooking and exposure to air resulted in increased plasma cortisol and lactate concentrations, while the combination of hooking and exposure to elevated temperature and air resulted in increased lactate and potassium concentrations. In fish that were towed in a net and exposed to air, cortisol, lactate, potassium and sodium concentrations increased, but when subjected to elevated temperature and air, no further increases occurred above the concentrations induced by net towing and air, suggesting a possible maximum of the physiological stress response. The results suggest that caution should be exercised when using physiological measures to quantify stress induced by capture and exposure to elevated temperature and air, that ultimately result in mortality, since the connections between physiological stress and mortality in bycatch processes remain to be fully understood.

Differential signaling and regulation of apical vs. basolateral EGFR in polarized epithelial cells.

PubMed

Kuwada, S K; Lund, K A; Li, X F; Cliften, P; Amsler, K; Opresko, L K; Wiley, H S

1998-12-01

Overexpression of the epidermal growth factor receptors (EGFR) in polarized kidney epithelial cells caused them to appear in high numbers at both the basolateral and apical cell surfaces. We utilized these cells to look for differences in the regulation and signaling of apical vs. basolateral EGFR. Apical and basolateral EGFR were biologically active and mediated EGF-induced cell proliferation to similar degrees. Receptor downregulation and endocytosis were less efficient at the apical surface, resulting in prolonged EGF-induced tyrosine kinase activity at the apical cell membrane. Tyrosine phosphorylation of EGFR substrates known to mediate cell proliferation, Src-homologous and collagen protein (SHC), extracellularly regulated kinase 1 (ERK1), and ERK2 could be induced similarly by activation of apical or basolateral EGFR. Focal adhesion kinase was tyrosine phosphorylated more by basolateral than by apical EGFR; however, beta-catenin was tyrosine phosphorylated to a much greater degree following the activation of mislocalized apical EGFR. Thus EGFR regulation and EGFR-mediated phosphorylation of certain substrates differ at the apical and basolateral cell membrane domains. This suggests that EGFR mislocalization could result in abnormal signal transduction and aberrant cell behavior.

A unique approach to demonstrating that apical bud temperature specifically determines leaf initiation rate in the dicot Cucumis sativus.

PubMed

Savvides, Andreas; Dieleman, Janneke A; van Ieperen, Wim; Marcelis, Leo F M

2016-04-01

Leaf initiation rate is largely determined by the apical bud temperature even when apical bud temperature largely deviates from the temperature of other plant organs. We have long known that the rate of leaf initiation (LIR) is highly sensitive to temperature, but previous studies in dicots have not rigorously demonstrated that apical bud temperature controls LIR independent of other plant organs temperature. Many models assume that apical bud and leaf temperature are the same. In some environments, the temperature of the apical bud, where leaf initiation occurs, may differ by several degrees Celsius from the temperature of other plant organs. In a 28-days study, we maintained temperature differences between the apical bud and the rest of the individual Cucumis sativus plants from -7 to +8 °C by enclosing the apical buds in transparent, temperature-controlled, flow-through, spheres. Our results demonstrate that LIR was completely determined by apical bud temperature independent of other plant organs temperature. These results emphasize the need to measure or model apical bud temperatures in dicots to improve the prediction of crop development rates in simulation models.

The Incremental Value of Magnetic Resonance Imaging for Identification of Apical Pouch in Patients with Apical Variant of Hypertrophic Cardiomyopathy.

PubMed

Vucicevic, Darko; Lester, Steven J; Appleton, Christopher P; Panse, Prasad M; Schleifer, John William; Wilansky, Susan

2016-04-01

The development of a left ventricular (LV) apical pouch in patients with apical hypertrophic cardiomyopathy (aHCM) has been thought to be the transition point that can become an apical aneurysm, which is linked to higher risk of adverse events. In our study, we sought to compare the ability of transthoracic echocardiography (echo) and cardiac magnetic resonance imaging (cMRI) to accurately identify the presence of an apical pouch or aneurysm in patients with aHCM. We retrospectively reviewed the charts of all consecutive patients that had features of aHCM on imaging. Data from cMRI and echo examinations were abstracted, and the ability of these diagnostic modalities to identify the presence of a LV apical pouch and aneurysm was analyzed. Of 31 patients with aHCM, 17 (54.8%) had an apical pouch and 2 were found to have apical aneurysm (6.5%) on cMRI. Echo with and without perflutren contrast was able to accurately identify both aneurysms, but only 47.1% (8/17) of apical pouches seen by cMRI. Two patients had apical thrombus that was identified by cMRI, but not by echo. Our findings indicate that cMRI is superior to echo in identifying apical pouches in patients with aHCM. Our results also suggest that in patients undergoing echo, the use of perflutren contrast for LV opacification increases the diagnostic yield. Further study is necessary to delineate whether earlier identification of an apical pouch will be of clinical benefit for patients with aHCM by altering clinical management and avoiding adverse cardiovascular events. © 2015, Wiley Periodicals, Inc.

Trends in Hysteropexy and Apical Support for Uterovaginal Prolapse in the United States from 2002 to 2012.

PubMed

Madsen, Annetta M; Raker, Christina; Sung, Vivian W

Our objective was to describe trends in hysteropexy and apical support for uterovaginal prolapse (UVP) from 2002 to 2012 in the United States. We identified patient and hospital variables associated with hysteropexy and apical support. We used the Nationwide Inpatient Sample and International Classification of Diseases, Ninth Revision codes to identify a population of women 18 years or older with UVP undergoing pelvic organ prolapse surgery from January 1, 2002, to December 31, 2012. Procedures were categorized as (1) hysteropexy, (2) obliterative with uterine preservation, (3) hysterectomy with apical support, (4) hysterectomy without apical support, and (5) other reconstruction without apical support. Categories were dichotomized into those with and without apical support. We used survey weights to obtain nationally representative estimates; χ and linear and logistic regression compared procedure groups. An estimated 815,184 hospital discharges of pelvic organ prolapse procedures for UVP occurred from 2002 to 2012. During this time, hysteropexies increased from 1.81% to 5.00% (P < 0.0001). From 2002 to 2012, hysterectomies with apical support increased (10.07% to 32.51%, P < 0.0001), hysterectomy without apical support decreased (27.14% to 17.12%, P < 0.0001), and reconstruction without apical support decreased (59.07% to 40.48%, P < 0.0001). In most recent years 2011 to 2012, 60% of women with UVP underwent inpatient surgery without an apical procedure. Age 52 years or older, Medicare payment, Northeast region, and urban teaching hospitals were associated with increased odds of apical support for UVP (P < 0.001 for all). Hysteropexy significantly increased in the United States from 2002 to 2012, although the overall proportion remains low. While hysterectomy without apical support is decreasing, approximately 60% of inpatient procedures performed for UVP do not address the apex.

Wortmannin-induced vacuole fusion enhances amyloplast dynamics in Arabidopsis zigzag1 hypocotyls

PubMed Central

Alvarez, Ashley Ann; Han, Sang Won; Toyota, Masatsugu; Brillada, Carla; Zheng, Jiameng; Gilroy, Simon

2016-01-01

Gravitropism in Arabidopsis shoots depends on the sedimentation of amyloplasts in the endodermis, and a complex interplay between the vacuole and F-actin. Gravity response is inhibited in zigzag-1 (zig-1), a mutant allele of VTI11, which encodes a SNARE protein involved in vacuole fusion. zig-1 seedlings have fragmented vacuoles that fuse after treatment with wortmannin, an inhibitor of phosphatidylinositol 3-kinase, and underscore a role of phosphoinositides in vacuole fusion. Using live-cell imaging with a vertical stage microscope, we determined that young endodermal cells below the apical hook that are smaller than 70 μm in length are the graviperceptive cells in dark-grown hypocotyls. This result was confirmed by local wortmannin application to the top of zig-1 hypocotyls, which enhanced shoot gravitropism in zig-1 mutants. Live-cell imaging of zig-1 hypocotyl endodermal cells indicated that amyloplasts are trapped between juxtaposed vacuoles and their movement is severely restricted. Wortmannin-induced fusion of vacuoles in zig-1 seedlings increased the formation of transvacuolar strands, enhanced amyloplast sedimentation and partially suppressed the agravitropic phenotype of zig-1 seedlings. Hypergravity conditions at 10 g were not sufficient to displace amyloplasts in zig-1, suggesting the existence of a physical tether between the vacuole and amyloplasts. Our results overall suggest that vacuole membrane remodeling may be involved in regulating the association of vacuoles and amyloplasts during graviperception. PMID:27816929

Analysis of the Ethylene Response in the epinastic Mutant of Tomato1

PubMed Central

Barry, Cornelius S.; Fox, Elizabeth A.; Yen, Hsiao-ching; Lee, Sanghyeob; Ying, Tie-jin; Grierson, Donald; Giovannoni, James J.

2001-01-01

Ethylene can alter plant morphology due to its effect on cell expansion. The most widely documented example of ethylene-mediated cell expansion is promotion of the “triple response” of seedlings grown in the dark in ethylene. Roots and hypocotyls become shorter and thickened compared with controls due to a reorientation of cell expansion, and curvature of the apical hook is more pronounced. The epinastic (epi) mutant of tomato (Lycopersicon esculentum) has a dark-grown seedling phenotype similar to the triple response even in the absence of ethylene. In addition, in adult plants both the leaves and the petioles display epinastic curvature and there is constitutive expression of an ethylene-inducible chitinase gene. However, petal senescence and abscission and fruit ripening are all normal in epi. A double mutant (epi/epi;Nr/Nr) homozygous for both the recessive epi and dominant ethylene-insensitive Never-ripe loci has the same dark-grown seedling and vegetative phenotypes as epi but possesses the senescence and ripening characteristics of Never-ripe. These data suggest that a subset of ethylene responses controlling vegetative growth and development may be constitutively activated in epi. In addition, the epi locus has been placed on the tomato RFLP map on the long arm of chromosome 4 and does not demonstrate linkage to reported tomato CTR1 homologs. PMID:11553734

The Triple Response Assay and Its Use to Characterize Ethylene Mutants in Arabidopsis.

PubMed

Merchante, Catharina; Stepanova, Anna N

2017-01-01

Exposure of plants to ethylene results in drastic morphological changes. Seedlings germinated in the dark in the presence of saturating concentrations of ethylene display a characteristic phenotype known as the triple response. This phenotype is robust and easy to score. In Arabidopsis the triple response is usually evaluated at 3 days post germination in seedlings grown in the dark in rich media supplemented with 10 μM of the ethylene precursor ACC in air or in unsupplemented media in the presence of 10 ppm ethylene. The triple response in Arabidopsis consists of shortening and thickening of hypocotyls and roots and exaggeration of the curvature of apical hooks. The search for Arabidopsis mutants that fail to show this phenotype in ethylene or, vice versa, display the triple response in the absence of exogenously supplied hormone has allowed the identification of the key components of the ethylene biosynthesis and signaling pathways. Herein, we describe a simple protocol for assaying the triple response in Arabidopsis. The method can also be employed in many other dicot species, with minor modifications to account for species-specific differences in germination. We also compiled a comprehensive table of ethylene-related mutants of Arabidopsis, including many lines with auxin-related defects, as wild-type levels of auxin biosynthesis, transport, signaling, and response are necessary for the normal response of plants to ethylene.

Amnioserosa cell constriction but not epidermal actin cable tension autonomously drives dorsal closure.

PubMed

Pasakarnis, Laurynas; Frei, Erich; Caussinus, Emmanuel; Affolter, Markus; Brunner, Damian

2016-11-01

Tissue morphogenesis requires coordination of multiple force-producing components. During dorsal closure in fly embryogenesis, an epidermis opening closes. A tensioned epidermal actin/MyosinII cable, which surrounds the opening, produces a force that is thought to combine with another MyosinII force mediating apical constriction of the amnioserosa cells that fill the opening. A model proposing that each force could autonomously drive dorsal closure was recently challenged by a model in which the two forces combine in a ratchet mechanism. Acute force elimination via selective MyosinII depletion in one or the other tissue shows that the amnioserosa tissue autonomously drives dorsal closure while the actin/MyosinII cable cannot. These findings exclude both previous models, although a contribution of the ratchet mechanism at dorsal closure onset remains likely. This shifts the current view of dorsal closure being a combinatorial force-component system to a single tissue-driven closure event.

Impaired left ventricular diastolic function is related to the formation of left ventricular apical thrombus in patients with acute anterior myocardial infarction.

PubMed

Choi, Ung Lim; Park, Jae-Hyeong; Sun, Byung Joo; Oh, Jin Kyung; Seong, Seok Woo; Lee, Jae-Hwan; Choi, Si Wan; Jeong, Jin-Ok; Kwon, In Sun; Seong, In-Whan

2018-05-01

Left ventricular (LV) apical thrombus is a clinically important complication which can cause systemic embolization in patients with anterior acute myocardial infarction (AMI). Systolic dysfunction has been a risk factor for developing LV apical thrombus in AMI patients. However, the role of diastolic dysfunction in the development of LV apical thrombus in these patients is still unknown. We performed this study to evaluate whether diastolic dysfunction can influence the development of LV apical thrombus in anterior AMI patients. We retrospectively analyzed all consecutive anterior AMI patients with available echocardiographic images within 1 month from January 2005 to April 2016. After gathering clinical characteristics from their medical records, systolic and diastolic functions were analyzed from digitally stored echocardiographic images. We included a total of 1045 patients (748 males, mean age 64 ± 12 years) with anterior AMI, and 494 (47%) were diagnosed as STEMI. The incidence of LV apical thrombus was 3.3% (34/1045). The LV apical thrombus group had larger LV diastolic dimension, larger LV diastolic and systolic volumes, and lower LVEF than the no LV thrombus group. The LV apical thrombus group showed higher mitral E velocity over mitral annular E' velocity ratio, an indicator of LV end-diastolic pressure (P < 0.001). In the LV apical thrombus group, the incidence of grade 2 diastolic dysfunction (32 vs 12%, P = 0.001) and grade 3 diastolic dysfunction (26 vs 2%, P < 0.001) were significantly higher than in the no LV apical thrombus group. The presence of more than grade 2 diastolic dysfunction, LVEF and presence of LV apical aneurysm were statistically significant factors associated with LV apical thrombus after the multivariate analysis. In conclusion, along with LV systolic dysfunction and LV apical aneurysm, LV diastolic dysfunction was also related with the presence of LV apical thrombus in patients with anterior AMI.

Is stump sprout treatment necessary to effectively control Phytophthora ramorum in California's wildlands?

Treesearch

Yana Valachovic; Richard Cobb; David Rizzo; Brendan Twieg; Chris Lee; Radoslaw Glebocki

2013-01-01

In California, wildland hosts that support sporulation of Phytophthora ramorum, such as California bay laurel (Umbellularia californica (Hook. & Arn.) Nutt.) and tanoak (Notholithocarpus densiflorus (Hook. & Arn.) Manos, Cannon & S.H. Oh), also develop prolific basal sprouts following...

Gateway National Recreational Area - Sandy Hook Unit : automated fee entrance plaza and intelligent transportation system technical requirements

DOT National Transportation Integrated Search

2009-01-01

The Volpe National Transportation Systems Center (Volpe Center) is providing technical : support to Sandy Hook, a unit of the Gateway National Recreation Area, in the planning and : concept development for possible Intelligent Transportation Systems ...

DETAIL VIEW OF THE BRIDGE CRANE HOOKS USED IN HB3 ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

DETAIL VIEW OF THE BRIDGE CRANE HOOKS USED IN HB-3 AND HB-4, FACING SOUTHWEST - Cape Canaveral Air Force Station, Launch Complex 39, Vehicle Assembly Building, VAB Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

Anharmonic Vibrations of an "Ideal" Hooke's Law Oscillator

ERIC Educational Resources Information Center

Thomchick, John; McKelvey, J. P.

1978-01-01

Presents a model describing the vibrations of a mass connected to fixed supports by "ideal" Hooke's law springs which may serve as a starting point in the study of the properties of irons in a crystal undergoing soft mode activated transition. (SL)

Establishing Apical Patency and its Effect on Endodontic Outcomes

DTIC Science & Technology

2012-06-01

canal space and periodontal ligament. Establishing apical patency is controversial with only 50% of dental programs in the United States teaching the... periodontal ligament (PDL) (1) where a small file can passively continue through the apical foramen (2). Establishing apical patency is...teeth with apical periodontitis that will eventually heal demonstrate signs of healing at 1 year follow-up, and almost 50% are completely healed

Apical closure of mature molar roots with the use of calcium hydroxide.

PubMed

Rotstein, I; Friedman, S; Katz, J

1990-11-01

Calcium hydroxide may induce apical root closure in affected mature teeth as well as in immature teeth. Once an apical hard tissue barrier is formed, a permanent root canal filling can be safely condensed. Two cases are described in which calcium hydroxide induced apical root closure in mature molar teeth where the apical constriction was lost because of chronic inflammatory process.

Laparoscopic inguinal hernia repair by the hook method in emergency setting in children presenting with incarcerated inguinal hernia.

PubMed

Chan, Kin Wai Edwin; Lee, Kim Hung; Tam, Yuk Him; Sihoe, Jennifer Dart Yin; Cheung, Sing Tak; Mou, Jennifer Wai Cheung

2011-10-01

The development of laparoscopic hernia repair has provided an alternative approach to the management of incarcerated inguinal hernia in children. Different laparoscopic techniques for hernia repair have been described. However, we hereby review the role of laparoscopic hernia repair using the hook method in the emergency setting for incarcerated inguinal hernias in children. A retrospective review was conducted of all children who presented with incarcerated inguinal hernia and underwent laparoscopic hernia repair using the hook method in emergency setting between 2004 and 2010. There were a total of 15 boys and 1 girl with a mean age of 30 ± 36 months (range, 4 months to 12 years). The hernia was successfully reduced after sedation in 7 children and after general anesthesia in 4 children. In 5 children, the hernia was reduced by a combined manual and laparoscopic-assisted approach. Emergency laparoscopic inguinal hernia repair using the hook method was performed after reduction of the hernia. The presence of preperitoneal fluid secondary to recent incarceration facilitated the dissection of the preperitoneal space by the hernia hook. All children underwent successful reduction and hernia repair. The median operative time was 37 minutes. There was no postoperative complication. The median hospital stay was 3 days. At a median follow-up of 40 months, there was no recurrence of the hernia or testicular atrophy. Emergency laparoscopic inguinal hernia repair by the hook method is safe and feasible. Easier preperitoneal dissection was experienced, and repair of the contralateral patent processus vaginalis can be performed in the same setting. Copyright © 2011 Elsevier Inc. All rights reserved.

A new orthodontic force system for moment control utilizing the flexibility of common wires: Evaluation of the effect of contractile force and hook length.

PubMed

Lai, Wei-Jen; Midorikawa, Yoshiyuki; Kanno, Zuisei; Takemura, Hiroshi; Suga, Kazuhiro; Soga, Kohei; Ono, Takashi; Uo, Motohiro

2018-01-01

The application of an appropriate force system is indispensable for successful orthodontic treatments. Second-order moment control is especially important in many clinical situations, so we developed a new force system composed of a straight orthodontic wire and two crimpable hooks of different lengths to produce the second-order moment. The objective of this study was to evaluate this new force system and determine an optimum condition that could be used in clinics. We built a premolar extraction model with two teeth according to the concept of a modified orthodontic simulator. This system was activated by applying contractile force from two hooks that generated second-order moment and force. The experimental device incorporated two sensors, and forces and moments were measured along six axes. We changed the contractile force and hook length to elucidate their effects. Three types of commercial wires were tested. The second-order moment was greater on the longer hook side of the model. Vertical force balanced the difference in moments between the two teeth. Greater contractile force generated a greater second-order moment, which reached a limit of 150 g. Excessive contractile force induced more undesired reactions in the other direction. Longer hooks induced greater moment generation, reaching their limit at 10 mm in length. The system acted similar to an off-center V-bend and can be applied in clinical practice as an unconventional loop design. We suggest that this force system has the potential for second-order moment control in clinical applications. Copyright © 2017. Published by Elsevier B.V.

Retrospective Evaluation of Safety, Efficacy and Risk Factors for Pneumothorax in Simultaneous Localizations of Multiple Pulmonary Nodules Using Hook Wire System.

PubMed

Zhong, Yan; Xu, Xiao-Quan; Pan, Xiang-Long; Zhang, Wei; Xu, Hai; Yuan, Mei; Kong, Ling-Yan; Pu, Xue-Hui; Chen, Liang; Yu, Tong-Fu

2017-09-01

To evaluate the safety and efficacy of the hook wire system in the simultaneous localizations for multiple pulmonary nodules (PNs) before video-assisted thoracoscopic surgery (VATS), and to clarify the risk factors for pneumothorax associated with the localization procedure. Between January 2010 and February 2016, 67 patients (147 nodules, Group A) underwent simultaneous localizations for multiple PNs using a hook wire system. The demographic, localization procedure-related information and the occurrence rate of pneumothorax were assessed and compared with a control group (349 patients, 349 nodules, Group B). Multivariate logistic regression analyses were used to determine the risk factors for pneumothorax during the localization procedure. All the 147 nodules were successfully localized. Four (2.7%) hook wires dislodged before VATS procedure, but all these four lesions were successfully resected according to the insertion route of hook wire. Pathological diagnoses were acquired for all 147 nodules. Compared with Group B, Group A demonstrated significantly longer procedure time (p < 0.001) and higher occurrence rate of pneumothorax (p = 0.019). Multivariate logistic regression analysis indicated that position change during localization procedure (OR 2.675, p = 0.021) and the nodules located in the ipsilateral lung (OR 9.404, p < 0.001) were independent risk factors for pneumothorax. Simultaneous localizations for multiple PNs using a hook wire system before VATS procedure were safe and effective. Compared with localization for single PN, simultaneous localizations for multiple PNs were prone to the occurrence of pneumothorax. Position change during localization procedure and the nodules located in the ipsilateral lung were independent risk factors for pneumothorax.

On the convexity of ROC curves estimated from radiological test results.

PubMed

Pesce, Lorenzo L; Metz, Charles E; Berbaum, Kevin S

2010-08-01

Although an ideal observer's receiver operating characteristic (ROC) curve must be convex-ie, its slope must decrease monotonically-published fits to empirical data often display "hooks." Such fits sometimes are accepted on the basis of an argument that experiments are done with real, rather than ideal, observers. However, the fact that ideal observers must produce convex curves does not imply that convex curves describe only ideal observers. This article aims to identify the practical implications of nonconvex ROC curves and the conditions that can lead to empirical or fitted ROC curves that are not convex. This article views nonconvex ROC curves from historical, theoretical, and statistical perspectives, which we describe briefly. We then consider population ROC curves with various shapes and analyze the types of medical decisions that they imply. Finally, we describe how sampling variability and curve-fitting algorithms can produce ROC curve estimates that include hooks. We show that hooks in population ROC curves imply the use of an irrational decision strategy, even when the curve does not cross the chance line, and therefore usually are untenable in medical settings. Moreover, we sketch a simple approach to improve any nonconvex ROC curve by adding statistical variation to the decision process. Finally, we sketch how to test whether hooks present in ROC data are likely to have been caused by chance alone and how some hooked ROCs found in the literature can be easily explained as fitting artifacts or modeling issues. In general, ROC curve fits that show hooks should be looked on with suspicion unless other arguments justify their presence. 2010 AUR. Published by Elsevier Inc. All rights reserved.

Biomechanical Analysis of the Proximal Adjacent Segment after Multilevel Instrumentation of the Thoracic Spine: Do Hooks Ease the Transition?

PubMed Central

Metzger, Melodie F.; Robinson, Samuel T.; Svet, Mark T.; Liu, John C.; Acosta, Frank L.

2015-01-01

Study Design Biomechanical cadaveric study. Objective Clinical studies indicate that using less-rigid fixation techniques in place of the standard all-pedicle screw construct when correcting for scoliosis may reduce the incidence of proximal junctional kyphosis and improve patient outcomes. The purpose of this study is to investigate whether there is a biomechanical advantage to using supralaminar hooks in place of pedicle screws at the upper-instrumented vertebrae in a multilevel thoracic construct. Methods T7–T12 spines were biomechanically tested: (1) intact; (2) following a two-level pedicles screw fusion from T9 to T11; and after proximal extension of the fusion to T8–T9 with (3) bilateral supra-laminar hooks, (4) a unilateral hook + unilateral screw hybrid, or (5) bilateral pedicle screws. Specimens were nondestructively loaded while three-dimensional kinematics and intradiscal pressure at the supra-adjacent level were recorded. Results Supra-adjacent hypermobility was reduced when bilateral hooks were used in place of pedicle screws at the upper-instrumented level, with statistically significant differences in lateral bending and torsion (p < 0.05 and p < 0.001, respectively). Disk pressures in the supra-adjacent segment were not statistically different among top-off techniques. Conclusions The use of supralaminar hooks at the top of a multilevel posterior fusion construct reduces the stress at the proximal uninstrumented motion segment. Although further data is needed to provide a definitive link to the clinical occurrence of PJK, this in vitro study demonstrates the potential benefit of “easing” the transition between the stiff instrumented spine and the flexible native spine and is the first to demonstrate these results with laminar hooks. PMID:27190735

Altered intragenic DNA methylation of HOOK2 gene in adipose tissue from individuals with obesity and type 2 diabetes

PubMed Central

Fernández-Bayón, Gustavo; Morales-Sánchez, Paula; Sanz, Lourdes; Turienzo, Estrella; González, Juan José; Martinez-Faedo, Ceferino; Suarez-Gutiérrez, Lorena; Ares, Jessica; Díaz-Naya, Lucia; Martin-Nieto, Alicia; Fernández-Morera, Juan L.; Fraga, Mario F.

2017-01-01

Aims/Hypothesis Failure in glucose response to insulin is a common pathology associated with obesity. In this study, we analyzed the genome wide DNA methylation profile of visceral adipose tissue (VAT) samples in a population of individuals with obesity and assessed whether differential methylation profiles are associated with the presence of type 2 diabetes (T2D). Methods More than 485,000 CpG genome sites from VAT samples from women with obesity undergoing gastric bypass (n = 18), and classified as suffering from type 2 diabetes (T2D) or not (no type 2 diabetes, NT2D), were analyzed using DNA methylation arrays. Results We found significant differential methylation between T2D and NT2D samples in 24 CpGs that map with sixteen genes, one of which, HOOK2, demonstrated a significant correlation between differentially hypermethylated regions on the gene body and the presence of type 2 diabetes. This was validated by pyrosequencing in a population of 91 samples from both males and females with obesity. Furthermore, when these results were analyzed by gender, female T2D samples were found hypermethylated at the cg04657146-region and the cg 11738485-region of HOOK2 gene, whilst, interestingly, male samples were found hypomethylated in this latter region. Conclusion The differential methylation profile of the HOOK2 gene in individuals with T2D and obesity might be related to the attendant T2D, but further studies are required to identify the potential role of HOOK2 gene in T2D disease. The finding of gender differences in T2D methylation of HOOK2 also warrants further investigation. PMID:29228058

On the convexity of ROC curves estimated from radiological test results

PubMed Central

Pesce, Lorenzo L.; Metz, Charles E.; Berbaum, Kevin S.

2010-01-01

Rationale and Objectives Although an ideal observer’s receiver operating characteristic (ROC) curve must be convex — i.e., its slope must decrease monotonically — published fits to empirical data often display “hooks.” Such fits sometimes are accepted on the basis of an argument that experiments are done with real, rather than ideal, observers. However, the fact that ideal observers must produce convex curves does not imply that convex curves describe only ideal observers. This paper aims to identify the practical implications of non-convex ROC curves and the conditions that can lead to empirical and/or fitted ROC curves that are not convex. Materials and Methods This paper views non-convex ROC curves from historical, theoretical and statistical perspectives, which we describe briefly. We then consider population ROC curves with various shapes and analyze the types of medical decisions that they imply. Finally, we describe how sampling variability and curve-fitting algorithms can produce ROC curve estimates that include hooks. Results We show that hooks in population ROC curves imply the use of an irrational decision strategy, even when the curve doesn’t cross the chance line, and therefore usually are untenable in medical settings. Moreover, we sketch a simple approach to improve any non-convex ROC curve by adding statistical variation to the decision process. Finally, we sketch how to test whether hooks present in ROC data are likely to have been caused by chance alone and how some hooked ROCs found in the literature can be easily explained as fitting artifacts or modeling issues. Conclusion In general, ROC curve fits that show hooks should be looked upon with suspicion unless other arguments justify their presence. PMID:20599155

The role of sediment compaction and groundwater withdrawal in local sea-level rise, Sandy Hook, New Jersey, USA

NASA Astrophysics Data System (ADS)

Johnson, Christopher S.; Miller, Kenneth G.; Browning, James V.; Kopp, Robert E.; Khan, Nicole S.; Fan, Ying; Stanford, Scott D.; Horton, Benjamin P.

2018-02-01

The rate of relative sea-level (RSL) rise at Sandy Hook, NJ (4.0 ± 0.5 mm/yr) was higher than The Battery, NY (3.0 ± 0.3 mm/yr) from 1900 to 2012 despite being separated by just 26 km. The difference cannot be explained by differential glacial isostatic adjustment (GIA; 1.4 ± 0.4 and 1.3 ± 0.4 mm/yr RSL rise, respectively) alone. We estimate the contribution of sediment compaction to subsidence at Sandy Hook using high-resolution grain size, percent organic matter, and porosity data from three upper Quaternary (≤13,350 cal yr) cores. The organic matter content (<2%) is too low to contribute to local subsidence. However, numerical modeling of the grain size-depth-age-porosity relationship indicates that compaction of deglacial silts likely reduced the column thickness by 10-20% over the past 13,350 cal yrs. While compaction rates were high immediately after the main silt deposition (13,350-13,150 cal yrs BP), rates decreased exponentially after deposition to an average 20th century rate of 0.16 mm/yr (90% Confidence Interval (C.I.), 0.06-0.32 mm/yr). The remaining ∼0.7 mm/yr (90% C.I. 0.3-1.2 mm/yr) difference in subsidence between Sandy Hook and The Battery is likely due to anthropogenic groundwater withdrawal. Historical data from Fort Hancock wells (2 km to the southeast of the Sandy Hook tide gauge) and previous regional work show that local and regional water extraction lowered the water levels in the aquifers underlying Sandy Hook. We suggest that the modern order of contribution to subsidence (highest to lowest) appears to be GIA, local/regional groundwater extraction, and compaction of thick Quaternary silts.

Characteristic Chromatogram: A Method of Discriminate and Quantitative Analysis for Quality Evaluation of Uncaria Stem with Hooks.

PubMed

Hou, Jinjun; Feng, Ruihong; Zhang, Yibei; Pan, Huiqin; Yao, Shuai; Han, Sumei; Feng, Zijin; Cai, Luying; Wu, Wanying; Guo, De-An

2018-04-01

It remains a challenge to establish new monographs for herbal drugs derived from multiple botanical sources. Specifically, the difficulty involves discriminating and quantifying these herbs with components whose levels vary markedly among different samples. Using Uncaria stem with hooks as an example, a characteristic chromatogram was proposed to discriminate its five botanical origins and to quantify its characteristic components in the chromatogram. The characteristic chromatogram with respect to the components of Uncaria stem with hooks with the five botanical origins was established using 0.02% diethylamine and acetonitrile as the mobile phase. The total analysis time was 50 min and the detection wavelength was 245 nm. Using the same chromatogram parameters, the single standard to determine multicomponents method was validated to simultaneously quantify nine indole alkaloids, including vincosamide, 3 α -dihydrocadambine, isocorynoxeine, corynoxeine, isorhynchophylline, rhynchophylline, hirsuteine, hirsutine, and geissoschizine methyl ether. The results showed that only the Uncaria stem with hooks from Uncaria rhynchophylla , the most widely used in the herbal market, showed the presence of these nine alkaloids. The conversion factors were 1.27, 2.32, 0.98, 1.04, 1.00, 1.02, 1.26, 1.33, and 1.25, respectively. The limits of quantitation were lower than 700 ng/mL. The total contents of 31 batches of Uncaria stem with hooks were in the range of 0.1 - 0.6%, except for Uncaria hirsuta Havil and Uncaria sinensis (Oliv.) Havil. The results also showed that the total content of indole alkaloids tended to decrease with an increase in the hook diameter. This showed that the characteristic chromatogram is practical for controlling the quality of traditional Chinese medicines with multiple botanical origins. Georg Thieme Verlag KG Stuttgart · New York.

Detection of Treponema Denticola in Symptomatic Apical Periodontitis and in Symptomatic Apical Abscesses by Real-Time PCR

PubMed Central

Ozbek, Selcuk M.; Ozbek, Ahmet; Erdogan, Aziz S.

2009-01-01

Objectives: The aim of this study was to investigate the presence of Treponema denticola in symptomatic apical periodontitis and in symptomatic apical abscesses by real-time polymerase chain reaction (PCR) method. Methods: Microbial samples were collected from 60 single-rooted teeth having carious lesions and necrotic pulps. For each tooth, clinical data including patient symptoms were recorded. Teeth were categorized by diagnosis as having symptomatic apical periodontitis or symptomatic apical abscess. Aseptic microbial samples were collected using paper points from 30 infected root canals and from aspirates of 30 abscesses. DNA was extracted from the samples by using a QIAamp® DNA mini-kit and analyzed with real-time PCR. Results: T. denticola was detected in 24 of 30 cases diagnosed as symptomatic apical abscesses (80%), and 19 of 30 cases diagnosed as symptomatic apical periodontitis (63.3%). In general T. denticola was found in 43 of 60 cases (71.6%). Conclusions: Our findings suggest that T. denticola can participate in the pathogenesis of symptomatic apical abscesses. PMID:19421390

Apical constriction is driven by a pulsatile apical myosin network in delaminating Drosophila neuroblasts.

PubMed

An, Yanru; Xue, Guosheng; Shaobo, Yang; Mingxi, Deng; Zhou, Xiaowei; Yu, Weichuan; Ishibashi, Toyotaka; Zhang, Lei; Yan, Yan

2017-06-15

Cell delamination is a conserved morphogenetic process important for the generation of cell diversity and maintenance of tissue homeostasis. Here, we used Drosophila embryonic neuroblasts as a model to study the apical constriction process during cell delamination. We observe dynamic myosin signals both around the cell adherens junctions and underneath the cell apical surface in the neuroectoderm. On the cell apical cortex, the nonjunctional myosin forms flows and pulses, which are termed medial myosin pulses. Quantitative differences in medial myosin pulse intensity and frequency are crucial to distinguish delaminating neuroblasts from their neighbors. Inhibition of medial myosin pulses blocks delamination. The fate of a neuroblast is set apart from that of its neighbors by Notch signaling-mediated lateral inhibition. When we inhibit Notch signaling activity in the embryo, we observe that small clusters of cells undergo apical constriction and display an abnormal apical myosin pattern. Together, these results demonstrate that a contractile actomyosin network across the apical cell surface is organized to drive apical constriction in delaminating neuroblasts. © 2017. Published by The Company of Biologists Ltd.