bluuebunny/crossref_metadata_2025_split huggingface dataset:
Extracting second-order system matrices from state space system
Authors: Houlston P R 
Published: September 2006

This technical note concerns the reformation of a second-order system from an arbitrary first-order system. At present, the majority of control literature is concerned with controlling systems within the first-order linearization of a system. The author is part of a growing community looking to expand the direct control of second-order systems and the benefits associated in doing so. However, there are potential stages of system modelling that may result in it being necessary to form the first-order form of the system, such as model reduction. This may have the effect of destroying the second-order notion of the system. The purpose of this note is to regain the structure of the second-order system and thus enable the benefits of direct second-order control to be realized. Although the problem itself has been previously resolved, the author proposes the virtue of a simpler method.
A model for tracheal study
Authors: Fredrickson John M. , Rogers John H. 
Published: September 2006

AbstractWhile attempting to devise a valvular device to prevent aspiration in tracheo‐esophageal anastomosis, we employed a model in the clog, which we feel would be very useful in the study of other tracheal problems. Essentially, a segment of trachea with its blood supply intact is isolated and turned through 90 degrees. One end of the segment is then anastomosed to the skin whereas the other end is either anastomosed to the gullet or covered with silastic, depending upon the required investigation. In both cases, after an interval of at least nine months, the segment continued to be lined by respiratory epithelium and no stenosis had occurred.Where silastic sheeting was employed to cover the end of the segment, the inner aspect of the silastic was covered with a thin layer of fibrous tissues lined by respiratory epithelium.
Shear Testing of Soft Rock Masses
Authors: Szymakowski J 
Published: September 2006

Abstract
Previous studies aimed at improving our understanding of rock mass behavior have incorporated laboratory techniques, case studies, or numerical methods. This study extends the laboratory based data by examining the behavior of relatively large scale jointed, soft rock mass samples in direct shear. The rock mass samples tested in this study were fabricated by cutting joint sets into a soft, synthetic siltstone block. Therefore, the development of new procedures and equipment for fabricating and shear testing the rock mass samples was required. The visual and measured data recovered from this testing was used to identify and model the prepeak behavior and failure mechanisms occurring within the samples. The observed prepeak behavior of the rock masses was found to comprise either sliding along one of the joint sets or rotation of a portion of the rock mass defined by the jointing pattern. All samples ultimately failed by shearing through intact rock coincident with the shear plane defined by the testing apparatus.
Instrumentation of an Unsaturated Expansive Soil Slope
Authors: Zhan TLT , Ng CWW , Fredlund DG 
Published: September 2006

Abstract
To understand the complex soil-water interaction in an unsaturated expansive soil slope subjected to rainfall infiltration, a comprehensive instrumentation and monitoring program was carried out on an 11-m high cut slope in Hubei of China. The instrumentation included jet-filled tensiometers, thermal conductivity suction sensors, moisture probes, earth pressure cells, inclinometers, vertical movement points, artificial rainfall simulator, a tipping bucket rain gage, a vee-notch flow meter, and an evaporimeter. The technique and experience associated with each of the instrumentations are presented in this paper with an emphasis on the difference from the instrumentation in nonexpansive soils. In particular, a deliberate sealing scheme was adopted to prevent the potential bypass water flow through the shallow cracks into the installation holes for the suction sensors and the moisture probes. All the instruments worked well throughout the two month monitoring period, during which two artificial rainfall events were created. The recorded responses in pore-water pressure, water content, horizontal stress, and soil deformation were reasonably consistent with one another.
Short-Beam-Shear Testing of Composite Rings With Variable Cross Section as Representative for Full-scale Delamination
Authors: Samyn P , Van Schepdael L , Leendertz JS , Van Paepegem W , De Baets P , Degrieck J 
Published: September 2006

Abstract
Carbon fiber reinforced/epoxy (CFR-E) rings are used as radial reinforcement for polymer bearing elements with diameter 249 mm, functioning under 150-MPa contact pressure. Full-scale loading revealed shear failure caused by a critical radial-axial shear stress. This stress, acting in a section of the CFR-E ring under nonhydrostatic conditions, should be representatively simulated on small-scale short-beam-shear tests. Finite element analysis will be used for verification of a small-scale stress failure criterion. A standard sample geometry could not be applied as the reinforcing ring contains machined edges leading to stress concentrations. A nonhydrostatic stress condition similar to full-scale tests should be simulated in the center of the small-scale beam. Therefore, the effects of various loading conditions and testing parameters such as cross-sectional geometry, beam support and span, beam curvature, and convex/concave loading are investigated. It is concluded that curved beams are preferred over flat geometries and convex loading is preferred above concave loading since it induces a nonhydrostatic stress situation identical to full-scale tests. During small-scale testing of nonrectangular ring sections, an asymmetric stress distribution near the machined edge is representatively simulated. Experimental short-beam-shear tests confirm the influence of the test geometry and a 27-kN equivalent normal load is required for avoiding fulls-cale fracture.
Influence of Interimplant Distance on Papilla Formation and Bone Resorption: A Clinical-radiographic Study in Dogs
Authors: de Oliveira Rafael R. , Novaes Arthur B. , Papalexiou Vula , Muglia Valdir A. , Taba Mário 
Published: September 2006

Abstract
Implant esthetics has been the focus of attention for the past decade, and one vital issue is the effect of interimplant distance on interimplant papilla formation and crestal bone loss. The aim of this study was to evaluate the effect of 1, 2, and 3 mm of interimplant distance on papilla formation and crestal resorption in submerged and nonsubmerged Ankylos implants after prosthetic restoration. Bilateral mandibular premolars of 7 dogs were extracted, and after 12 weeks each dog received 8 implants. Implants were placed so that 3 interimplant distances were created at 1 mm (group 1), 2 mm (group 2), and 3 mm (group 3). The sides and the position of the groups were randomly selected. Twelve weeks after placement, the implants received metallic prostheses that allowed 5 mm of space between the prosthetic contact point (CP) and the crestal bone (CB). After 8 weeks, the distance between the CP and the papilla (CP-P) and the gingival height at the distal proximal aspect of the prosthesis (CP-DE) was clinically measured. Radiographic images were obtained to measure the distance of the CP to the CB within the interimplant surfaces (CP-IP) and adjacent to the edentulous surfaces (CP-ED). The clinical measurement of CP-P for submerged and nonsubmerged implants was 3.57 ± 1.17 mm and 3.10 ± 0.82 mm for group 1, 3.57 ± 0.78 mm and 3.16 ± 0.87 mm for group 2, and 3.35 ± 0.55 mm and 3.07 ± 0.93 mm for group 3. The CP-DE was 3.25 ± 0.77 mm for submerged and 2.78 ± 0.64 mm for nonsubmerged implants. The CP-IP for the submerged and nonsubmerged implants was 6.91 ± 0.95 mm and 7.68 ± 2.73 mm for group 1, 7.46 ± 1.43 mm and 5.87 ± 1.71 mm for group 2, and 7.72 ± 0.81 mm and 7.59 ± 1.33 mm for group 3. The CP-ED was 6.77 ± 1.33 mm for submerged implants and 6.03 ± 1.58 mm for nonsubmerged implants. There were no statistical significant differences for any of the measured parameters. We conclude that when the distance from the CP to the CB was 5 mm, interimplant distances of 1 to 3 mm did not affect papilla formation or crestal resorption of submerged or nonsubmerged implants in the dog model.
Calcification at the Interface Between Titanium Implants and Bone: Observation With Confocal Laser Scanning Microscopy
Authors: Nishikawa Tetsunari , Masuno Kazuya , Mori Masahiko , Tajime Yasuhiro , Kakudo Kenji , Tanaka Akio 
Published: September 2006

Abstract
It has not been previously possible to observe bone formation in undecalcified sections with titanium implants at high magnification because of the difficulty in sectioning bone together with implants. A method for examining the bone-implant interface in undecalcified sections is described in which implants are left in situ and confocal laser scanning microscopy (CLSM) is used to examine both the implant surface and adjacent bone. Pulsing of animals at different times with the fluorescent dyes calcein and alizarin red permitted assessment of temporal patterns of bone formation by CLSM. Reflectivity of the polished implant surface permitted accurate assessment of the position of the implant relative to labeled bone. The analysis showed that bone first formed as thin processes towards and across the implant surface, followed by further bone formation behind these processes. The interface between calcified bone tissue and the implant surface was characterized by a 10-μm space. The CLSM technique enabled detailed observations of new bone formation at the titanium implant interface.
Sinus Floor Augmentation Using a Composite Graft of Bone Morphogenic Protein-2 and Allogenic Cancellous Bone (Puros): Case Report
Authors: Whitesides Lee M. , Radwan Alaaaldin , Sharawy Mohamed 
Published: September 2006

AbstractReconstruction of the atrophic maxilla is a difficult task. The gold standard for such reconstruction is autogenous bone. Presently, many excellent products are available to the dental surgeon to facilitate alveolar reconstruction in the absence of autogenous bone. This study describes the use of bone morphogenic protein in combination with allogenic bone substitute (Puros) to reconstruct the maxilla in preparation for dental implant placement.
The Relevance of a New Generation of Monobloc Posts and Impression Copings for Implant-supported Fixed Partial Dentures: A 2-year Clinical Prospective Study With the FM-Clip System on EVL Implants (SERF)
Authors: Leclercq Philippe , Zenati Charlotte , Dohan David M. 
Published: September 2006

Abstract
The use of monobloc posts for implant-supported fixed partial dentures is interesting for biomechanical and biological reasons, but it suffers from a lack of precision during the impression phase. The use of a new generation of monobloc posts associated with individual impression copings with a piston offers a simple and efficient impression procedure for small and medium implant-supported fixed partial dentures. This article presents the FM-Clip system for EVL implants composed of new straight monobloc posts and small impression copings with a piston for precise impressions and easy production of implant-supported fixed partial dentures.
Fabrication of a Cement- and Screw-retained Multiunit Implant Restoration
Authors: Uludag Bulent , Celik Gozde 
Published: September 2006

Abstract
Retrieval of cemented implant restorations can be difficult for both the patient and the dentist. The method described in this article combines the advantages of cement- and screw-retained restorations. Abutment screws can be easily reached by the screw access channel prepared in the waxing phase; the restoration can be retrieved without destroying the implants and prosthesis. This article describes a simple and reliable method to fabricate a retrievable cemented prosthesis.
Effects of Periodontal Cell Grafts and Enamel Matrix Proteins on the Implant–Connective Tissue Interface: A Pilot Study in the Minipig
Authors: Craig Ronald G. , Kamer Angela R. , Kallur Sathya P. , Inoue Miho , Tarnow Dennis P. 
Published: September 2006

Abstract
We have developed an experimental model to help identify and characterize factors necessary for periodontal connective tissue attachment formation on dental implants. In this pilot study, we report the effect of autogenous periodontal cell grafts, with and without the application of enamel matrix derivative (EMD), on the implant–connective tissue interface. Periodontal ligament (PDL) and gingival connective tissue (GCT) cultures were established from an adult minipig. Implants were placed in osteotomies prepared with exaggerated countersinks that served as recipient sites for autogenous cell grafts in bilateral edentulated posterior mandibular sextants. In addition, 1 side received an application of EMD before placement of the autogenous cell grafts. A bioabsorbable membrane covering the coronal portion of the implants was placed before closure. After 8 weeks, quantitative histomorphometric and qualitative light microscopic analyses revealed that the implants that received gelatin vehicle alone were surrounded by bone, whereas the implants that received GCT cell grafts were mostly surrounded by fibrous connective tissue. In contrast, implants that received PDL cells without the application of EMD demonstrated good bone contact, but strands of epithelium were observed in the implant–connective tissue interface. Implants that received PDL cells and EMD also had good bone contact but without evidence of epithelium. A cementum-like interface was not observed in any of the groups. Results of this pilot study suggest that EMD and the type of cell populations present in the implant wound-healing environment may alter the implant–connective tissue interface.
Shade Matching by Dental Students
Authors: Winkler Sheldon , Boberick Kenneth G. , Weitz Kasia S. , Datikashvili Isaac , Wood Robert 
Published: September 2006

Abstract
Dental students achieved a high identification rate for darker shades (P14 and P24) on the Portrait IPN shade guide, which represent the highest chroma and lowest value in the grayish and reddish yellow hue groups. A high identification rate was also obtained for P32, representing the lowest chroma and highest value in the reddish gray hue group. The data suggest that dental students had the most difficulty determining the correct hue group for unmarked shade tabs. Incorrect responses tended to remain in the same value and chroma range but were selected in a different hue group.
An Evaluation of Two Commercially Prepared Feeds on Growth Performance and Liver Condition of Juvenile African Cichlids Pseudotropheus socolofi and Haplochromis ahli
Authors: Royes Juli-Anne B , Murie Debra J , Francis-Floyd Ruth , Terrell Scott 
Published: September 2006

Abstract
A 12-week feeding trial was conducted to evaluate growth performance and hepatocyte changes in juvenile African cichlids Pseudotropheus socolofi and Haplochromis ahli fed commercial diets commonly used on cichlid farms in south Florida. Fish were fed either a trout starter pellet diet (TP diet; 52% crude protein, 17% lipid) or a mixed flake feed diet (fish flake [FF] diet) (47% crude protein, 7% lipid). For both species, growth was significantly greater (P &lt; 0.05) in fish fed the TP diet than in fish fed the FF diet, H. ahli administered the FF diet exhibiting the slowest growth. The hepatosomatic index was not significantly different among treatments (P &gt; 0.1). Histological examination revealed severe vacuolation of hepatocytes in P. socolofi fed the TP diet and moderate vacuolation in H. ahli fed the TP diet. Moderate vacuolation of hepatocytes was observed in P. socolofi fed the FF diet, and only mild vacuolation was found in H. ahli fed the FF diet. The lipid-rich TP diet may be suitable for commercial production of juvenile African cichlids up to 12 weeks of age, but prolonged feeding may result in excess lipid deposition and necrosis of the liver. Feeds like the FF diet, which produced slower growth but lower lipid deposition in livers, may be more suitable as a maintenance diet for cichlids in the home aquarium.
Influence of Dietary Replacement of Menhaden Oil with Canola Oil on Fatty Acid Composition of Sunshine Bass
Authors: Wonnacott Emily J , Lane Ryan L , Kohler Christopher C 
Published: September 2006

Abstract
The replacement of menhaden Brevoortia spp. oil with graded levels of canola oil in diets fed for 20 weeks to sunshine bass (female white bass Morone chrysops × male striped bass M. saxatilis) significantly impacted the fatty acid composition of fillets and livers. As the amount of canola oil increased from 0% to 100% of the oil in the diet, the amount of 18:1(n-9) and 18: 2(n-6) fatty acids in fillets increased linearly, whereas the amounts of 20:5(n-3), 22:6(n-3), long-chain n-3 highly unsaturated fatty acids (HUFAs), and total long-chain HUFAs in the fillets decreased linearly. Total long-chain n-3 HUFA levels did not differ significantly between fillets from fish fed a diet with 50% canola oil and those from fish fed 100% menhaden oil. The experimental diets also significantly altered the fatty acid compositions of the livers, though fatty acid levels were highly variable within and among treatments and differences usually were not as pronounced as differences in fillets. We observed no significant differences in weight gain, feed conversion, or total lipid content among fish fed the different diets. Our results suggest that high levels of canola oil in growing diets of sunshine bass could be used for the majority of the production cycle, to be followed by a “finishing” diet that would elevate HUFA levels, thereby increasing the fillets' nutritional benefit to the human consumer.
A Review of Methods for Detoxification and Neutralization of Formalin in Water
Authors: Masters Amanda L 
Published: September 2006

Abstract
Formalin is used at many fish farms and is typically discharged untreated from these facilities as part of normal hatchery effluents. The majority of aquaculture facilities that are regulated for formalin discharge are regulated on a concentration basis. These facilities most commonly use dilution methods to manage formalin concentrations in effluents. Dilution is not feasible at all farms, however, due to the unavailability of dilution water and the necessity of complex management practices to achieve adequate dilution. As hatchery discharge regulations become stricter, larger amounts of dilution water are required, which are not always available; therefore, practical methods of treating formalin in hatchery effluents are needed. This paper reviews the physical, chemical, and biological methods of aqueous formaldehyde neutralization and detoxification that have been tested to date and identifies those methods that may be practical for use at fish farms, including the application of sodium sulfite, commercially available neutralizers, or a combination of hydrogen peroxide and ferric ions. More research on the use of these treatment methods at aquaculture facilities is recommended to determine overall treatment effectiveness, cost, and practicality.
Ammonia Tolerance by Sunshine Bass Fry: Implication for Use of Ammonium Sulfate to Control Prymnesium parvum
Authors: Barkoh Aaron , Smith Dennis G , Schlechte J Warren , Paret John M 
Published: September 2006

Abstract
Ammonium sulfate, (NH4)2SO4, is recommended for controlling the toxic alga Prymnesium parvum in fish production ponds. Because the un-ionized ammonia from ammonium sulfate that kills P. parvum is also toxic to fish, we determined the maximum concentration of un-ionized ammonia nitrogen that 4–5-d-old sunshine bass (female white bass Morone chrysops × male striped bass M. saxatilis) can tolerate for 48 h; this was part of a study to assess the feasibility of using ammonium sulfate in sunshine bass fingerling production ponds. We compared sunshine bass treated with six ammonium sulfate treatments— 3, 5, 8, 10, 15, and 20 mg (NH4)2SO4/L at pH 8.5 and 20°C—with untreated fish (control). Fish mortality and total ammonia nitrogen were monitored for 48 h, and un-ionized ammonia nitrogen concentrations were calculated from the total ammonia nitrogen values. Mean mortalities for all treatments were 0.0–3.3% during the first 24 h and 8.0– 37.1% after 48 h. The mean 48-h cumulative mortality was 8.0% for the control, 10.4% for ammonium sulfate concentrations of 3–15 mg/L, and 37.1% for 20 mg/L. Mean mortalities for un-ionized ammonia nitrogen concentrations of 0.0–0.25 mg/L were approximately 5–12% and were not statistically different. Mean mortality increased significantly at 0.33 mg/L of un-ionized ammonia nitrogen, resulting in 37% mortality of the fish. Because sunshine bass fry withstood un-ionized ammonia nitrogen concentrations of up to 0.25 mg/L (89% survival) and the minimum concentration of un-ionized ammonia nitrogen needed to control P. parvum is 0.17 mg/L, it appears that ammonium sulfate treatments that result in un-ionized ammonia nitrogen concentrations of 0.17 to 0.25 mg/L will control P. parvum while minimizing mortality in sunshine bass fry.
Comparison of Three Methods of Size Grading Channel Catfish Stockers
Authors: Green Bartholomew W , Heikes David L , Goodwin Andrew E 
Published: September 2006

Abstract
The stocking of size-graded catfish into production ponds should increase production efficiency, but grading large numbers of fish with existing technology is laborious. We evaluated the effectiveness of a mechanical grader recently developed at the University of Arkansas at Pine Bluff (UAPB) relative to that of box and sock graders and assessed injuries sustained by stocker channel catfish Ictalurus punctatus during grading. Three 0.25-acre ponds were stocked at 11,777 lb/acre. Initial total length (TL) ranged from 6.3 to 15.7 in, and initial weight of individuals ranged from 0.04 to 1.10 lb. The fish population in each pond was divided into three groups graded with the box grader, UAPB grader, or sock grader. Fish were graded twice with the box and UAPB graders; a bar spacing of 13/32 in was used to grade off small fish and a spacing of 13/8 in to grade off large fish. Sock grader mesh size was 13/8 in. Mean weights and lengths of the size-classes produced by grading (small, medium, and large) were compared to those of the initial population in each pond. Blood samples were collected from sampled fish, and serum was analyzed for creatine phosphokinase (CPK) and lactate dehydrogenase (LDH) activities to assess fish injury levels. Each grader separated the initial population into distinct populations. Mean weight and TL of the medium size-class was significantly lower for the UAPB grader than for the box grader. The frequency distributions of the fish populations obtained from each grader differed significantly. Undergrade and overgrade error for the medium size-class did not differ significantly between the box and UAPB graders. Undergrade error averaged 5.4% for TL and 1.6% for individual weight; overgrade error averaged 7.8% for TL and 10.3% for weight. Serum CPK and LDH activities were highly variable, which prevented detection of significant treatment differences.