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Aim: The aim was to report a fenestration technique for gap reduction of acetabular depression fractures. Case presentation: A 76-year-old man suffered from severe left leg pain. The computed tomography scanning showed a displaced acetabular depression fracture, including a third fracture fragment in the center of the acetabular weight-bearing area. We performed a fenestration technique to fenestrate the outer plate of ilium to push down the dislocated fragment of the fracture. The patient was pain-free with good functional outcome of the hip joint at three years after operation. Conclusion: The fenestration technique is useful for displaced acetabular depression fractures. We performed open reduction in this particular case, but the technique may be done less invasively with the use of hip arthroscopy.

Osteoarthritis (OA) and rheumatoid arthritis (RA) are widespread disabling joint disorders that are considered to be polygenic in nature. This study investigated the spatial expression patterns of all six known human CCN genes using end-stage OA and RA joint samples. We performed in situ hybridization and histological analysis to investigate the spatial expression patterns of human CCN genes using joint tissues obtained during total knee and hip joint replacement procedures on patients with advanced OA or RA. Normal joint tissues taken while performing bipolar hip replacement surgeries were used as controls. All CCN genes were expressed at higher levels in OA and RA synovial samples as compared with normal controls. Whereas CCN3 and CCN6 were undetectable in control, OA, and RA cartilage, CCN1, CCN2, CCN4, and CCN5 were expressed to a greater extent in OA and RA knee cartilage. Our results indicate an involvement of several CCN genes in the pathophysiology of OA and RA.

The linear penetration rates for ceramic femoral heads on conventional and highly cross-linked polyethylene were measured and compared with radiographs taken in the standing and supine position taken three weeks postoperatively and at final follow-up. Seventy-five patients (83 hips) with conventional polyethylene (group-1) and two hundred and seventy five patients (300 hips) with highly cross-linked polyethylene (group-2) were studied. Follow-up periods were 14.5years in group-1 and 8.6years in group-2. The average penetration rates in group-1 were 0.17mm/year in supine position and 0.18mm/year in standing position (P

Introduction: To investigate a long-term in vivo deterioration of polymethylmethacrylate (PMMA) bone cement over time, we evaluated retrieved PMMA cement in terms of chemical elements presenting in the cement using energy dispersive analysis of X-rays; Knoop hardness; and the Young’s modulus using scanning acoustic microscopy. Materials and Methods: For mechanical evaluation, we could neglect the influences of entrapped air bubbles or blood by the use of small specimens. The study was based on thirteen cement samples (six used in the acetabulum and seven in the femur) derived from eight patients (age at revision surgery: mean 72.5, range 68 to 79). All of these samples were Simplex-P?cement. They were functioning well at least ten years after the previous surgery. Duration until revision surgery was ranged 12 to 25 years (average, 17.4 years). The reason for revision was aseptic mechanical loosening. Twenty samples of Simplex-Preg; cement were served by manually mixing as a control. Results: The average of the hardness of the cement was 17.0 ± 1.2 (range, 13.4-20.6). In the control, the hardness was 17.8 ± 1.5 (range, 14.0-24.6). There was no significant difference between these values. The mean of Young’s modulus of the cement was 5.61 ± 0.19 GPa (range, 5.09-6.10). In the control, the modulus was 6.04 ± 0.13 GPa (range, 5.68-6.45). Although the modulus was significantly less than that of the control, there was only 7% decrease in average between twelve and twenty-five years in vivo. Conclusions: Our results suggest that long-term implantation and functional loading in vivo may not be the limiting factor in the mechanical integrity of the bone cement.

Fourteen hips in 14 patients (all female; average age, 64 years) with severe bone defects due to developmental dysplasia of the hip or migration of the socket were treated with hydroxyapatite block with impacted morselized bone graft in conjunction with a cemented socket. All patients were followed clinically in a prospective fashion, and radiographs were analyzed retrospectively. One initial patient had 17-year follow-up, whereas the remaining 13 patients had follow-up between 4 and 6.5 years. No acetabular components were revised, including the socket of a 17-year postoperative case that remains rigidly fixed and supported by the graft and hydroxyapatite block with only mild polyethylene wear and minor osteolysis. Osteointegration and good clinical outcome were achieved in all cases by reconstruction with this technique in total hip arthroplasty.

Background The acetabular fossa is thought to be located in the center of the acetabulum, and acetabular reaming in total hip arthroplasty is conventionally performed in the center of the fossa. However, the actual location of the fossa and the influence that hypoplasia or deformity may have on the position of the fossa are unknown. We hypothesized that the fossa is located in the center of the acetabulum, regardless of hypoplasia or deformity. Methods Fifty patients with normal hips (normal hip group), 50 patients with dysplasia who underwent rotational acetabular osteotomy (dysplastic hip group), and 46 patients with osteoarthritis who underwent total hip arthroplasty (osteoarthritic hip group) were evaluated by computed tomography (CT) imaging. On the horizontal plane that passes through the center of the femoral head, the center line of the acetabulum was defined as the perpendicular bisector of the anterior and posterior rims of the acetabulum. The angle and distance of the center of the acetabular fossa in relation to the center line of the acetabulum were evaluated; furthermore, the center position of the fossa from the anterior margin of the acetabulum was calculated as a ratio relative to acetabular size. A 1-way analysis of variance was performed to compare measurements among the 3 groups. Results The center of the acetabular fossa was positioned anteriorly to the center line of the acetabulum in all 3 groups. The mean center angle of the acetabular fossa was 14.0° ± 3.8°, 15.2° ± 5.6°, and 14.9° ± 5.5° in the normal, dysplastic, and osteoarthritic hip groups, respectively (p = 0.33). The mean center distance of the acetabular fossa was 5.6 ± 1.8, 5.8 ± 2.3, and 6.1 ± 2.2 mm, respectively (p = 0.55). The mean center position of the acetabular fossa was 38.8% ± 3.3%, 38.5% ± 4.2%, and 38.3% ± 3.9%, respectively (p = 0.71). Conclusions The center of the acetabular fossa is positioned anteriorly to the center of the acetabulum, and the positioning is affected by neither dysplasia nor osteoarthritis. The preconception that the center of the acetabulum corresponds to the center of the acetabular fossa may risk eccentric reaming, possibly damaging the anterior wall. Level of evidence Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

When a gas standard mixture is consumed, the pressure in its cylinder is reduced. We studied how much this affects the concentrations of the gas standard mixtures. We prepared VOCs (Volatile Organic Compaunds) gas standard mixtures (100 vol ppb), and analyzed their concentrations at 10, 8, 6, 4, 2, 1 MPa each by GC-FID. As a result, the concentrations were not changed in 3 components (dichloromethane, 1,3-butadiene, vinyl chloride). However, the concentrations increased with the consumption in 5 components (benzene, chloroform, 1,2-dichloroethane, trichloroethylene, tetrachloroethylene). 1,2-dichloroethane had the largest increase, and its concentrations in 1 MPa was 3% higher than that in 10 MPa. Therefore the pressure should be checked when using a gas standard mixture. Also, it should be renewed if necessary.

The gravimetric method is the most popular method for preparing reference gas mixtures with high accuracy. We have designed and manufactured novel mass measurement equipment for gravimetric preparation of reference gas mixtures. This equipment consists of an electronic mass-comparator with a maximum capacity of 15 kg and readability of 1 mg and an automatic cylinder exchanger. The structure of this equipment is simpler and the cost is much lower than a conventional mechanical knife-edge type large balance used for gravimetric preparation of primary gas mixtures in Japan. This cylinder exchanger can mount two cylinders alternatively on the weighing pan of the comparator. In this study, the performance of the equipment has been evaluated. At first, the linearity and repeatability of the mass measurement were evaluated using standard mass pieces. Then, binary gas mixtures of propane and nitrogen were prepared and compared with those prepared with the conventional knife-edge type balance. The comparison resulted in good consistency at the compatibility criterion described in ISO6143:2001.

I ntraoperative blood loss can occur in many different ways—hypotensive anesthesia or continuous epidural anesthesia methods, surgical technique, or prolonged operation time can all influence bleeding during surgery. In fact, patients undergoing periacetabular osteotomy (PAO) lose more blood during surgery and receive transfusions more frequently [3] compared to patients undergoing total joint arthroplasty. Although blood management strategies such as blood donation and blood salvage have been used to curb intraoperative blood loss for patients undergoing PAO, these approaches carry their own risks. Another approach to reducing intraoperative bleeding is the use of an antifibrinolytic agent, such as tranexamic acid (TXA). TXA has been shown to reduce blood loss and minimize transfusions in various surgical subspecialties [1, 2]. However, one concern associated with TXA is the possible increased risk of thrombosis. Additionally, there are no studies in the literature that have examined the effects of TXA on blood loss associated with PAO.

Morphologic features of the hips, in particular those features germane to determination of acetabular and femoral anteversion angles and femoral head offset, were studied in 50 male and 50 female human skeletons with bilateral normal joints. Four distinct configurations were identified relative to t

Polyethylene wear is a major contributor to osteolysis and subsequent aseptic loosening of prosthetic components in total hip arthroplasty. Use of ion implantation as a surface modification to the metallic bearing component of orthopaedic implants may be an effective means of reducing wear debris at the bearing interface. In July 1991, low friction ion treated femoral heads were introduced. This study evaluates the effect of the low friction ion treated femoral head on polyethylene wear. Fifty-five total hip arthroplasties (53 patients) with low friction ion treated femoral heads followed up a minimum of 3 years were matched with 55 total hip arthroplasties (47 patients) without low friction ion treated femoral heads for the same postoperative period. Socket wear was evaluated radiographically. Case matching and strict inclusion criteria were used to control for known factors influencing polyethylene wear. These criteria included: (1) cases matched for gender and age within 2 years; (2) diagnosis limited to osteoarthritis or avascular necrosis of the femoral head only; (3) femoral head diameter limited to 26 or 28 mm only; (4) hydroxyapatite coated femoral stem of the same design and a metal backed socket of the one of two designs with the same polyethylene insert; and (5) minimum followup of 3 years. The linear wear rate of polyethylene was 0.161 +/- 0.095 mm per year in the group without the low friction ion treated heads and 0.116 +/- 0.101 mm per year in the low friction ion treated group. The volumetric wear rates were 74.5 +/- 44.3 mm3 per year for the group without the low friction ion treated heads and 57.8 +/- 51.1 mm3 per year for the low friction ion treated group. Assuming the sensitivity of these measurements can detect these small differences in wear accurately, these results suggest low friction ion treated prosthetic heads are useful in reducing polyethylene wear at 3-year minimum followup.

Background and Objectives. Needle trauma may cause peripheral nerve injuries during performance of peripheral nerve block. Methods. Four types of 21-gauge needles for regional anesthesia were compared: a beveled nerve block needle (Quincke type); a short-tapered needle with a side orifice (Whitacre type); a long-tapered needle with a side orifice (Sprotte type); and a long-tapered double needle combining an inner pencil-point fine needle with an outer truncated conical needle (a new type). This new needle was developed to reduce the potential for nerve injury while retaining a suitable flow rate of anesthetic solution and the ability to inject the solution precisely at the point of paresthesia elicited by the tip. Each type of needle was used to produce puncture injuries to rabbit sciatic nerves. Eighteen specimens werestudied within each needle group. The beveled needle was used to produce two different types of nerve injuries by inserting it either transverse or longitudinal to the nerve fibers. Each histologic specimen of the nerve with the needle puncture was surfacestained with hematoxylin-eosin and Bodian's method. Subsequently, the number of damaged axons was histomorphologically counted and statistically evaluated. Results. Both long-tapered needles produced significantly fewer transected axons than the beveled needle inserted with the bevel longitudinal to the nerve fibers. Conclusion. The long-tapered needles produced the least number of transected nerve fibers after sciatic nerve puncture.

A new self-hardening paste was made by using a combination of chitosan, hydroxyapatite (HA) granules, ZnO, and CaO. The sol was made by dissolving 0.1 g of chitosan in a solution of 0.1 g malic acid and 2.0 mL physiological saline solution. Mixed with 0.03 g of CaO and 0.04 g of ZnO powders was 2.77 g (55 wt %) of HA granules which had a homogeneous pore distribution and a porosity of 35-48%. The size of the granules was set for 0.1-0.3 mm. Kneading and setting of the paste generated a little amount of heat (32.8 degrees C) as compared with the heat produced by polymethyl-methacrylate (PMMA) bone cement (114.5 degrees C). The pH value of chitosan-HA-hardened composite after setting was nearly equal to that of human plasma (pH 7.4), while that of PMMA bone cement maintained an acid pH of 4.7. Hydroxyapatite granules less than 0.1 mm, 0.1-0.3 mm, or 0.3-0.6 mm were set using chitosan sol. The size of the granules did not influence the compressive strength of the set chitosan-HA-hardened composite. The greatest compressive strength of chitosan-HA-hardened composite was obtained by using 55 wt % of HA granules. The strength of the chitosan-HA-hardened composite was comparable to that of the cancellous bone derived from tibial eminentia, but was considerably lower than that of the PMMA bone cement.

The important role of Helicobacter pylori (H. pylori) in idiopathic duodenal ulcer disease is widely acknowledged. Treatment with amoxicillin and omeprazole has been highly successful in eradicating H. pylori in some pilot studies. We conducted a study in patients with active duodenal ulcer disease and H. pylori colonization of gastric mucosa using a combination of amoxicillin and lansoprazole. Lansoprazole has been shown to exhibit lower MIC than omeprazole. Sixty three patients who qualified for admission to the study were randomly assigned to receive either oral lansoprazole (30 mg, p.o., qam, daily for 6 weeks) (n = 30) or lansoprazole (6 weeks) plus amoxicillin (1500 mg, p.o, t.i.d., daily for 2 weeks) (n = 33). Six weeks after the initiation of treatment with lansoprazole, healing of the ulcers was assessed using electronic endoscope according to the classification of Sakita & Miwa. When lansoprazole alone was administered to the patients, H. pylori dormancy was attained in none of the patients, whereas dormancy was ascertained in 17 out of 33 patients when lansoprazole and amoxicillin were administered in combination. H. pylori dormancy was assessed by 13C urea breath test, histological examination of gastric mucosa and rapid urease test. Endoscopic evaluations revealed that S2/S1 ratio was significantly higher in patients with H. pylori dormancy than in those without. The results of our study confirmed that treatment to eradicate H. pylori with drugs such as lansoprazole and amoxicillin is effective in the healing of idiopathic duodenal ulcer disease.

A clay containing hydroxyapatite (HA clay), which was made by mixing HA granules (range of sizes: 0.1–0.3 mm) and a saline solution of sodium alginate, was inserted into the medullary canal of an osteotomized rabbit's tibia with a Ti-6Al-4V titanium alloy implant. Each implant had a conical portion for bearing load. The shear strength of the bone-implant interface for the implant with HA clay was significantly greater than that for the implant without HA clay 3 months postoperatively (P < .02), while there was no significant difference between the two strengths 1 week postoperatively. Under microscopic observation, the percentage of area of newly developed bone was also significantly greater for the implant with HA clay than for the implant without HA clay 3 months postoperatively (P < .04). This study suggests that HA clay encouraged adequate bone fixation of the loaded implant in 3 months, while the clay was not effective for immediate fixation. © 1995 John Wiley & Sons, Inc.

In uncemented total hip arthroplasty, a complete filling of the gap between femoral prosthesis and the host bone is difficult and defects would remain, because the anatomy of the reamed intramedullary canal cannot fit the prosthesis. Therefore, it seems practical to fill the gap with a clay containing hydroxyapatite (HA), which has an osteoconductive character. The clay (HA clay) is made by mixing HA granules (size 0.1 mm or more) having a homogeneous pore distribution and a porosity of 35-48 vol%, and a viscous substance such as a saline solution of sodium alginate (SSSA). In the first experiment, the ratio of HA granules and sodium alginate in SSSA is set for the same handling properties of HA clay and polymethylmethacrylate bone cement (standard viscosity) before hardening. As a result, the ratio is set for 55 wt% of HA in the clay and 12.5 wt% of sodium alginate in SSSA (i.e., HA:sodium alginate:saline solution = 9.8:1:7). In the second study, the gap between the femoral stem and bone model is completely filled with HA clay. However, the gap is not filled only with HA granules or HA granules mixed with saline solution. In the third animal experiment, using an unloaded model, histology shows that HA clay has an osteoconductive property bridging the gap between the implant and the cortical bone without any adverse reaction. HA clay is considered a useful biomaterial to fill the gap with adequate bone ingrowth.

Background Broad dissection with a long skin incision and detachment of the gluteus medius muscle performed for rotational acetabular osteotomy (RAO) can result in weakness in abduction strength of the hip. We use a surgical procedure for RAO that minimizes operative invasion of soft tissue and reduces incision length compared with conventional procedures. Questions/Purposes We evaluated the clinical results of this less-invasive RAO comparing it with the more-invasive prior procedure with respect to improvement in clinical hip scores and radiographic coverage and overall hip survival after the procedure. Methods In this less-invasive exposure, the medial gluteus muscle is retracted to expose the ilium without detachment from the iliac crest. Similarly, the rectus femoris muscle tendon is retracted, not excised. The lateral part of the osteotomized ilium is cut to form the bone graft instead of harvesting it from the outer cortical bone of the ilium. Between 2000 and 2009, 62 patients (71 hips) underwent this procedure. Twenty-eight hips had early-stage osteoarthritis and 43 had advanced-stage osteoarthritis. Mean patient age was 40 years at the time of surgery. We evaluated improvement in hip scores (Merle d’Aubigné-Postel, Japanese Orthopaedic Association) and radiographic appearance (lateral center-edge angle, Sharp’s angle, acetabular head index [AHI]). Kaplan-Meier survivorship analysis was performed. Mean followup was 5 years (range, 2.0–10.4 years). Results Clinical hip scores improved postoperatively. On average, lateral center-edge angle, Sharp’s angle, and AHI improved by 38°, 11°, and 42%, respectively. Predicted 10-year survival rates were 100% and 72% for hips with early- and advanced-stage osteoarthritis, respectively. Conclusions In hips with early-stage osteoarthritis treated by this less-invasive approach, no progression of osteoarthritis was documented and Trendelenburg gait was avoided. However, further investigation is necessary for hips with advanced-stage osteoarthritis. Level of Evidence Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Fourteen hips in 14 patients (all female; average age, 64 years) with severe bone defects due to developmental dysplasia of the hip or migration of the socket were treated with hydroxyapatite block with impacted morselized bone graft in conjunction with a cemented socket. All patients were followed clinically in a prospective fashion, and radiographs were analyzed retrospectively. One initial patient had 17-year follow-up, whereas the remaining 13 patients had follow-up between 4 and 6.5 years. No acetabular components were revised, including the socket of a 17-year postoperative case that remains rigidly fixed and supported by the graft and hydroxyapatite block with only mild polyethylene wear and minor osteolysis. Osteointegration and good clinical outcome were achieved in all cases by reconstruction with this technique in total hip arthroplasty.

The binding properties of a new radioligand, [3H]bunazosin, were studied in membranes of human prostates with benign prostatic hypertrophy (BPH). Specific binding of [3H]bunazosin was saturable, reversible, and of high affinity (Kd = 0.55 +/- 0.04 nM). The density of [3H]bunazosin binding sites (Bmax) was 676 +/- 33 fmol/mg. protein. [3H]Bunazosin rapidly associated with its binding sites in membranes of human prostates and reached steady state by 20 min. at 25C. The rate constants for association and dissociation of [3H]bunazosin binding were calculated to be 0.11 +/- 0.01/nM/min. and 0.05 +/- 0.02/min. (n = 4), respectively. Seven alpha 1 adrenoceptor antagonists competed with [3H]bunazosin for the binding sites in the rank order: R-(-)-YM-12617 greater than prazosin greater than SGB-1534 greater than bunazosin greater than terazosin greater than naftopidil greater than urapidil. In parallel studies with [3H]bunazosin, the Kd and Bmax values for [3H]prazosin binding in human prostates were slightly lower. There was a similarity in the potency and rank order of seven alpha 1, adrenoceptor antagonists for the inhibition of [3H] bunazosin and [3H]prazosin binding in human prostates. The new [3H]bunazosin binding assay in human prostates is remarkable for its low degree of nonspecific binding as compared to [3H]prazosin, especially at high ligand concentrations. Thus, [3H]bunazosin may become a useful radioligand for the further analysis of the alph 1 adrenoceptor binding sites in human prostates.

The step-by-step method and the simultaneous method have been experimentally examined to estimate the dynamic model of PUMA 560. The merits and demerits of the both method are discussed and compared. To evaluate the accuracy of the estimated parameter values, the joint angle trajectories of a real motion and the simulated motions have been compared. From those results it can be said the step-by-step method is more accurate way to estimate the model parameter values than the simultaneous method. The estimated parameter values obtained by the both method will be accurate for the purpose of model based control of the industrial manipulator.

A new national R&D project on novel communication systems using a number of high altitude large airships(stratospheric platform). The pla t form will be used as base station and switching center for various types of communication systems. The goal of the national project is to develop key technology for stratospheric platform system in several years and to demonstrate it using airship in stratosphere . [1] This paper describes various ap plications and network system design of IMT2000 mobile communications system using stratospheric plat form (SPF) and plan of mission flight tests 2002. INTRODUCTION Research on the use of stratospheric platforms (SPFs) for wireless communication is being con ducted in Japan jointly by the Ministry of Education , Culture, Sports, Science and Technology (MEXT) and the Ministry of Public Management, Home Affairs, Posts and Telecommunications (MPMHAPT). An SPF is an unmanned airship kept at a stratospheric altitude and used for radio communications, broadcasting, earth observation, and monitoring. [1] The requirements for an SPF are station-keeping efficiency, long period undisturbed operation , [mission payload and power supply capability], mission recovery (reuse), and stratospheric environment-friendly. Therefore an unmanned large airship type is the most promising candidate . The Telecommunications Advancement Organization of Japan ( TAO) [2] and The Communication * Researcher, Yokosuka Stratospheric Platform Research Center, TAO of Japan, Yokosuka, Japan † General Manager, Yokosuka Stratospheric Platform Research Center, TAO of Japan, Yokosuka, Japan ‡ Head, Research Planning Office, Communications Research Laboratory, Japan § Group Leader, Senior Researcher, Communications Research Laboratory, Yokosuka, Japan ¶ Executive Director Business Operation Division NEC TOSHIBA Space Systems, Ltd . Research Laboratory (CRL) are research ing and developing a radio communications system and a broadcast ing system that use SPFs. In this article we will describe characteristics and various applications and network system designs for mobile communications (IMT2000 system) that use SPFs. We also describe the flight tests planned for 2002. Experiments and demonstrations will be conducted using a helicopter flying 3 km high. Finally, we describe a stratospheric communication experiment planned for 2002 that will use a so lar-powered stratospheric plane, the “Pathfinder Plus”, and be conducted in cooperation with NASA. R&D SCHEDULE & PROGRESS (1998-2004) (1) 1998: Conceptual design of mobile communications systems using SPFs (2) 1999: Basic design of mobile communications systems using experimental airship (3) 2000: Design and manufacture of on -board mobile communications system for preliminary experiment (4) 2001: Design and manufacture of IMT2000 base station system for preliminary exp eriment (5) 2002: 1) Preliminary experiment using helicopter 2) Stratospheric communication experiment us ing solar-powered stratospheric plane deve loped by NASA (6) 2003: Design and manufacture of IMT2000 test system for low-altitude position-controlled airship test (7) 2004: Low-altitude position-controlled airship test The R&D schedule for the mobile communic ation system using SPFs is shown in t able 1. [2] 20th AIAA International Communication Satellite Systems Conference and Exhibit 12-15 May 2002, Montreal, Quebec, Canada AIAA 2002-2002 Copyright © 2002 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved. American Institute of Aeronautics and Astronautics 2 In 2000 and 2001, we designed and manufa ctured the on-board communication equipment and the ground communication equipment. In 2002, pre liminary experiments and demonstrations will be conducted using a helicopter fly ing 3 km high. The original plan called for the use of a stratospheric position-controlled airship. However, airship development has been delayed, so a helicopter will be used instead. The IMT2000 system uses the 2-GHz band, which was newly allocated at the WRC2000. A stratospheric communication experiment planned for May and June 2002 will use a solar -powered stratospheric plane, the “Pathfinder Plus”, developed by NASA. [3] CHARACTERISTICS OF MOBILE COMMUNICATIONS SYSTEM USING SPFS Mobile communications systems using SPFs have the follo wing characteristics. (1) The wide coverage area of the airships a llows for an economical communications system. (2) The high elevation angle and line-o f-site transmission minimize propagation loss and significantly reduce multi-path fading. (3) The propagation loss and delay are less than with a sate llite system. (4) The service area can be flexibly set. Moreover an IMT2000 system using the 2-GHz band can operate with a low elevation angle. An SPF flying 20 km high can cover a 200km service area with a 10-degree elevation angle (EL). (Fig. 1) For example , the entire country of Canada could be covered by 360 SPFs . (Fig. 2) If te rrestrial IMT2000 base stations were used, 463,129 of them would be needed. (Assuming each base station (BS), coverage area has a 2.5-km radius.) In other words one SPF can cover the same area as 1300 terrestrial BSs. [4] Using SPFs is thus an efficient way to services rural areas, particularly mountain and forest areas . They are effective in urban areas because the e ffects of blocking by buildings and multi-path fading are low due to the high elevation angle and line-o f-site transmission. Therefore, a network system using SPFs has lower propagation loss than terrestrial systems. For example, the propagat ion loss of an IMT2000 terrestrial system using the 2-GHz band is in proportion to the 4 power of the distance. That of an SPF system is in proportion to the square of the distance. (The 100-km propagation loss of an SPF system is the same as the several-km loss of a terrestrial system.) Therefore, (In terms of propagation loss) terrestrial IMT2000 terminal equipment can be used for SPF mobile communication system. And the propagation distance is much shorte r than that of satellite communication, the propagation loss of the SPF system (130dB) is 30 d B lower than that of LEO (low earth orbit) systems (160 dB) and 60 d B lower than that of GEO (geo-stationary earth orbit) systems (190 d B). Fig. 2 Example service areas for Canada (EL=10 deg) A L T : 2 0 k m E L : 1 0 S P F : 3 6 2 Fig. 1 Coverage area with EL of 10 deg 200 km (656,000 ft) 5 km (16,400 ft) Altitude 20 km (65,600 ft) Terrestrial Base Station SPF

The online version of the original article can be found under doi:10.1007/s11999-012-2599-6.

The all-inside meniscal suture was performed by using new arthroscopic instruments with a soft and fine (4-0 gauge) polyfilament thread that yielded relatively small knots so as to be innocuous to articular cartilage. No neurovascular injury, infection, or any other complication had occurred intraoperatively and postoperatively in this technique.

A clay containing hydroxyapatite (HA) was developed for use as a filling material between an uncemented implant and bone. It consists of 55% HA granules greater than 0.1 mm in size with a homogeneous pore distribution and a porosity of 35% to 48% in a saline solution of sodium alginate (6%). Ti-6A1-4V alloy rods with smooth surfaces were implanted into the distal medullary canal of one osteotomised tibia of 32 Japanese white rabbits. Sixteen rods were inserted with HA clay and 16 without the clay to act as a control group. Six of each group were killed at one week and ten at 12 weeks postoperatively. The pull-out strength of the implants with HA clay was significantly greater at 12 weeks (p < 0.05), as was the percentage of the area of the new bone (p < 0.05). The study suggests that HA clay has an osteoconductive property, allowing adequate bone fixation across a gap at an early stage. The use of HA clay to enhance the early stability of uncemented components may help to improve the functional outcome of total joint arthroplasty.

Ammonia is an important compound in the chemical industry. It is widely used and is the basis for producing other compounds containing nitrogen. Ammonia is also very hazardous, and consequently emissions of ammonia need be controlled and monitored. In the past years, several national metrology institutes have developed facilities for the preparation of Primary Standard gas Mixtures (PSMs), dynamically generated ammonia mixtures and facilities for comparing and certifying gas mixtures containing ammonia. The amount-of-substance fraction level of ammonia chosen for this key comparison is 30–50 µmol/mol. The results of this key comparison revealed that there is at present no consensus among static and dynamic techniques for gas mixture preparation for this component in this range. As key comparison reference value (KCRV), the mean of the three methods is used. In its uncertainty, no allowance is made for the observed biases. With respect to the KCRV, only two laboratories report consistent results. When grouped in accordance with the employed methods, the results are consistent. Further experimental work is needed. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

Binding properties of naftopidil and alpha 1-adrenoceptor antagonists to alpha-adrenoceptors in prostates from benign prostatic hypertrophy (BPH) were characterized by radioreceptor assays using [3H]prazosin and [3H]rauwolscine. Specific binding of [3H]prazosin and [3H]rauwolscine in human prostatic membranes was saturable and of high affinity, and it showed a pharmacological specificity which characterized alpha 1 and alpha 2-adrenoceptors, respectively. Naftopidil and several alpha 1 antagonists competed for prostatic [3H]prazosin binding in order: R-(-)-YM-12617 greater than prazosin greater than bunazosin greater than terazosin greater than naftopidil greater than urapidil, and the inhibitory effect (Ki = 11.6 nM) of naftopidil was 10 to 45 times less potent than quinazoline derivatives such as prazosin, bunazosin and terazosin. The potencies of these antagonists in competing for [3H]prazosin binding sites in human prostates correlated well with their pharmacological potencies (pA2). Scatchard analysis indicated that the decrease of prostatic [3H]prazosin binding by naftopidil was due to a marked increase in the Kd value without a change in the Bmax value. The inhibition of prostatic [3H]prazosin binding by naftopidil was reversible. Naftopidil also inhibited prostatic [3H]rauwolscine binding (Ki = 70.0 nM). Thus, it is suggested that naftopidil antagonizes alpha 1-adrenoceptors in human prostates in a competitive and reversible manner.

The pilot study evaluated the level of comparability of laboratories' preparative capabilities for gravimetric nitrogen monoxide/nitrogen primary reference mixtures in the range (30?70) ?mol/mol. The comparison was designed so that measurements would be performed at a central laboratory (the BIPM) and measurement results compared to values assigned by each national metrology institute (NMI) based on gravimetry using regression analysis. The advantages and complications in organizing a comparison with measurements performed at a central laboratory have been clearly demonstrated, notably: analytical measurement uncertainties can be reduced; a degree of equivalence parameter and its uncertainty can be calculated; regression analysis and therefore reference values for the comparison are highly dependent on the data set chosen for regression analysis and the uncertainty ascribed to the analytical measurement system within the central laboratory. Participating laboratories reported standard uncertainties for gravimetric preparation which ranged from 0.01% to 0.22% relative to the nitrogen monoxide mole fraction value. Following FTIR analysis, the standards of three laboratories (six gas standards in total) were omitted from the regression analysis data set, as a significant difference between reported and measured values of impurity contents was observed. An additional standard was removed from the regression analysis set as its deviation from the regression line was of the same order of magnitude as the standards already omitted. A regression line consistent with the remaining calibration data (15 gas standards) could be obtained by increasing estimates of the coordinating laboratory's measurement uncertainty by approximately a factor of three, resulting in analytical standard uncertainties of 0.12% (at 70 ?mol/mol) and 0.27% (at 30 ?mol/mol), and predicted standard uncertainties of the nitrogen monoxide mole fractions of 0.09 ?mol/mol. Reported standard uncertainties related to gravimetric preparation ranged from 0.004 ?mol/mol to 0.11 ?mol/mol with a median of 0.03 ?mol/mol. Nevertheless, comparison of the results of CCQM-P73 to previous key comparisons for nitrogen monoxide in nitrogen at 100 ?mol/mol (CCQM-K1.c and EUROMET.QM-K1.c) illustrates the reductions in uncertainties that can be achieved through a comparison with measurements performed at a central facility. Main text. To reach the main text of this paper, click on Final Report. The final report has been peer-reviewed and approved for publication by the CCQM-GAWG.

The aim of this comparison was to compare capabilities for the preparation and value assignment of gas mixture standards for sulphur dioxide in air (or nitrogen), maintained at national metrology institutes (NMIs). The measurements in this key comparison took place in 2006. There were three participants and one coordinating laboratory. The key comparison reference value (KCRV) was based on the gravimetric preparation for all components. The range of the nominal amount-of-substance fractions of the comparison standard is 90 µmol/mol to 100 µmol/mol. The Chemical Evaluation Research Institute (CERI, Japan) prepared gravimetric mixture samples of sulfur dioxide in nitrogen in 10 L aluminium cylinders with a passivated inner surface. The homogeneity and long term stability of these samples were evaluated at CERI before and after the shipment of the cylinders to the participants. The uncertainty of the standard gases including the long term stability was estimated to be 0.1 %. Each participating laboratory was shipped one cylinder to be analyzed and then returned to the CERI. Three participants submitted results that were within 0.6% of the relevant reference value. In these cases, the estimated uncertainties were larger than the deviation from the reference value. The agreement of the results in this key comparison is good. CERI is the link laboratory between CCQM-K1.d and APMP.QM-K4. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

The aim of this comparison was to compare capabilities for the preparation and value assignment of gas mixture standards for ethanol in nitrogen, maintained at national metrology institutes (NMIs). The measurements in this key comparison took place in 2006. There were three participants and one coordinating laboratory. The key comparison reference value (KCRV) was based on the gravimetric preparation for all components. The range of the nominal amount-of-substance fractions of the comparison standard is 100 µmol/mol to 130 µmol/mol. The Chemical Evaluation Research Institute (CERI, Japan) prepared gravimetric mixture samples of ethanol in nitrogen in 10 L aluminium cylinders and the homogeneity and long-term stability of these samples were evaluated at CERI before and after the shipment of the cylinders to the participants. Each participating laboratory was shipped one cylinder to be analyzed and then returned to the CERI. Each sample was reanalyzed to verify whether the contents were stable throughout the comparison. These measurements showed no significant change in the amount fraction within the estimated uncertainty of the measurements. Two of the three participants submitted results that were within 0.1% of the relevant reference value. In these cases, the estimated uncertainty was larger than the deviation from the reference value. CERI was the link laboratory between CCQM-K4 and APMP.QM-K4. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

The first key comparison on carbon dioxide in nitrogen dates from 1993–1994 (CCQM-K1.b). Since then, numerous national metrology institutes (NMIs) have been setting up facilities for gas analysis, and have developed claims for their Calibration and Measurement Capabilities (CMCs) for these type mixtures. In the April 2005 meeting of the CCQM Gas Analysis Working Group, a policy was proposed to repeat key comparisons for stable mixtures every 10 years. Consequently in 2007 the key comparison CCQM-K52 'Carbon dioxide in synthetic air' was carried out. This comparison is consistent with the proposed policy and enables NMIs that could not participate in the previous comparison to take part. This report describes the results of a key comparison for carbon dioxide in synthetic air. The amount-of-substance fraction level of carbon dioxide chosen for this key comparison (360 µmol/mol) represents the ambient level of this component in air. In total 18 NMIs and one WMO laboratory participated in the comparison. The agreement of the results in this key comparison is very good. With a few exceptions, the results agree within 0.3% (or better) with the key comparison reference value. Most of the participants that did not participate in CCQM-K1.b do very well. In some cases, the uncertainties claimed are quite large in comparison with the NMIs for which this comparison is a true 'repeat', but the observed differences with the KCRV usually reflect that these claims are realistic. All participants in CCQM-K1.b that participated in this key comparison show improved results. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

Accurate measurements of sulphur dioxide at the concentrations found in ambient air have become essential to support monitoring and legislation concerned with air quality. In general, the primary element of quality assurance for field instruments is regular calibration using certified gas mixtures. The concentration range chosen for this Key Comparison (240 nmol/mol to 320 nmol/mol) is defined by appropriate European standards and is typical of similar levels used around the world. The travelling standards used for the comparison were prepared commercially by a supplier with a proven track record of preparing stable mixtures of the relevant gases. The coordinating laboratory (NPL) carried out stability checks on the mixtures and determined the amount fraction using a primary gravimetric permeation facility. These data were used to determine the drift rate (and uncertainty) of each standard. The results for the 11 participants in CCQM-K26.b and the one participant in CCQM-P50.b are presented in this report. Degrees of equivalence have been calculated based on a reference value (corresponding to the KCRV) derived from the primary gravimetric facility used by the coordinating laboratory. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

The aim of this comparison was to compare capabilities for the preparation and value assignment of gas mixture standards for benzene, chloroform, dichloromethane, trichloroethylene, tetrachloroethylene, 1,2-dichloroethane, 1,3-butadiene and vinyl chloride in nitrogen (HAPs-8), maintained at national metrology institutes (NMIs). The measurements in this key comparison took place in 2003. There were six participants and one coordinating laboratory. The key comparison reference value (KCRV) was based on the gravimetric preparation for all components. The range of the nominal amount-of-substance fractions of the comparison standard is 90 nmol/mol to 110 nmol/mol. The Chemical Evaluation Research Institute (CERI, Japan) prepared gravimetric mixture samples of HAPs-8 in 10 L aluminium cylinders and the homogeneity and long term stability of these samples were evaluated at CERI before and after the shipment of the cylinders to the participants. Each participating laboratory was shipped one cylinder to be analysed and then returned to the CERI. Each sample was reanalysed to verify whether the contents were stable throughout the comparison. These measurements showed no significant change in the amount fraction within the estimated uncertainty of the measurements except for 1,2-dichroloethane. These deviations were combined into the uncertainty of the comparison samples but were small enough compared to the deviations from values reported by participating laboratories and the gravimetric values of the samples. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

This report describes key comparison APMP.QM-K4 that was held under the auspices of the Asia Pacific Metrology Program (APMP) Technical Committee for Amount of Substance (TCQM) in 2000?2001, and piloted by the NMIJ. The report was checked by the CCQM Working Group on Gas Analysis and approved by the CCQM. Four national metrology institutes, CSIR-NML (South Africa), CMS-ITRI (Taiwan), KRISS (Republic of Korea) and NMIJ/CERI (Japan) participated in the key comparison. ERL-HIAST (Syria) participated as a 'study' and the results will not be included in MRA Appendix B. The protocol used is equivalent to that of the CCQM-K4, and the link laboratory is NMIJ. Gas mixtures of ethanol in air with a nominal amount-of-substance fraction of 120 ?mol/mol were prepared in cylinders using the gravimetric method by CERI. One cylinder was delivered to each participant and analysed based on the participant's standard. Two of the participants have their own gravimetric primary standards, one carried out the analysis using the standard by a static volumetric method, and two purchased gravimetrically mixed gases in cylinders from other national laboratories for their standards. This key comparison demonstrates that the level of comparability between three of the four participants is adequate to meet the requirements for ethanol/air mixtures at this amount-of-substance fraction. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the Mutual Recognition Arrangement (MRA).