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Background and Hypothesis: The objective of this study was to analyze available whole genome sequencing from an adolescent male patient diagnosed with osteosarcoma (OS) in 2014. OS is a primary bone malignancy that most commonly affects the pediatric population. Precision medicine techniques provide new opportunities to improve treatment of OS patients. Pharmaceutical annotation tools such as PharmacoDB and DGIdb can help indicate chemotherapy agents that may benefit patients based on their molecular profiles. We hypothesize that these tools can indicate genome-specific chemotherapy agents for OS after genomic data has been aligned and analyzed. Project Methods: A PDX pipeline and retrospective study were performed that identified and compared pharmaceutical treatment options from software tools with the chemotherapy provided. Gene alignment and variant calling were used to process and analyze DNA sequencing data; germline and somatic mutations were also identified. Ensembl VEP was used for variant annotation. PharmacoDB and DGIdb were then applied to identify potentially beneficial medications. Results: Gene variant annotation indicated 54 potentially high impact mutations. Of these, DGIdb identified 15 drug-gene interactions. PharmacoDB identified no drugs that target any of the genes containing the 54 high impact mutations. For the entire mutated gene list, DGIdb identified 398 drug-gene interactions. After gene set enrichment, DGIdb identified medications targeting genes of pathways such as “O-glycan processing” and “Diseases of glycosylation”. Potentially harmful variants in the NPRL3 gene were identified. Because NPRL3 is a component of the Gator1 complex that serves as a negative regulator of mammalian target of rapamycin complex 1 (mTORC1), the identified variants in NPRL3 could have played a role in the patient’s OS. Potential Impact: This study will foster future collaborations to evaluate the pharmaceutical tool recommendations for this patient’s derived cell lines. These efforts will determine the efficacy of and identify improvements for computational treatment recommendation systems.

Restoring somatosensory feedback to people with limb amputations is crucial to improve prosthetic control. Multiple studies have demonstrated that peripheral nerve stimulation and targeted reinnervation can provide somatotopically relevant sensory feedback. While effective, the surgical procedures required for these techniques remain a major barrier to translatability. Here, we demonstrate in four people with upper-limb amputation that epidural spinal cord stimulation (SCS), a common clinical technique to treat pain, evoked somatosensory percepts that were perceived as emanating from the missing arm and hand. Over up to 29 days, stimulation evoked sensory percepts in consistent locations in the missing hand regardless of time since amputation or level of amputation. Evoked sensations were occasionally described as naturalistic (e.g. touch or pressure), but were often paresthesias. Increasing stimulus amplitude increased the perceived intensity linearly, without increasing area of the sensations. These results demonstrate the potential of SCS as a tool to restore somatosensation after amputations., eLife digest Even some of the most advanced prosthetic arms lack an important feature: the ability to relay information about touch or pressure to the wearer. In fact, many people prefer to use simpler prostheses whose cables and harnesses pass on information about tension. However, recent studies suggest that electrical stimulation might give prosthesis users more sensation and better control. After an amputation, the nerves that used to deliver sensory information from the hand still exist above the injury. Stimulating these nerves can help to recreate sensations in the missing limb and improve the control of the prosthesis. Still, this stimulation requires complicated surgical interventions to implant electrodes in or around the nerves. Spinal cord stimulation – a technique where a small electrical device is inserted near the spinal cord to stimulate nerves – may be an easier alternative. This approach only requires a simple outpatient procedure, and it is routinely used to treat chronic pain conditions. Now, Chandrasekaran, Nanivadekar et al. show that spinal cord stimulation can produce the feeling of sensations in a person’s missing hand or arm. In the experiments, four people who had an arm amputation underwent spinal cord stimulation over 29 days. During the stimulation, the participants reported feeling electrical buzzing, vibration, or pressure in their missing limb. Changing the strength of the electric signals delivered to the spinal cord altered the intensity of these sensations. The experiments are a step toward developing better prosthetics that restore some sensation. Further studies are now needed to determine whether spinal cord stimulation would allow people to perform sensory tasks with a prosthetic, for example handling an object that they cannot see.

Background Recent advances in kernel-based Deep Learning models have introduced a new era in medical research. Originally designed for pattern recognition and image processing, Deep Learning models are now applied to survival prognosis of cancer patients. Specifically, Deep Learning versions of the Cox proportional hazards models are trained with transcriptomic data to predict survival outcomes in cancer patients. Methods In this study, a broad analysis was performed on TCGA cancers using a variety of Deep Learning-based models, including Cox-nnet, DeepSurv, and a method proposed by our group named AECOX (AutoEncoder with Cox regression network). Concordance index and p-value of the log-rank test are used to evaluate the model performances. Results All models show competitive results across 12 cancer types. The last hidden layers of the Deep Learning approaches are lower dimensional representations of the input data that can be used for feature reduction and visualization. Furthermore, the prognosis performances reveal a negative correlation between model accuracy, overall survival time statistics, and tumor mutation burden (TMB), suggesting an association among overall survival time, TMB, and prognosis prediction accuracy. Conclusions Deep Learning based algorithms demonstrate superior performances than traditional machine learning based models. The cancer prognosis results measured in concordance index are indistinguishable across models while are highly variable across cancers. These findings shedding some light into the relationships between patient characteristics and survival learnability on a pan-cancer level.

Restoring somatosensory feedback to people with limb amputations is crucial for improving prosthesis acceptance and function. Epidural spinal cord stimulation is a commonly used clinical procedure that targets sensory neural pathways in the dorsal spinal cord to treat pain conditions. A similar approach could be developed as a clinically translatable means to restore somatosensation in amputees. We show that epidural stimulation of the dorsal spinal cord evoked sensory percepts, perceived as emanating from the amputated arm and hand, in four people with upper-limb amputation. After an initial caudal movement immediately following the implantation, the leads stabilized, exhibiting a median migration of

Integrative and complementary non-pharmacological treatments have proven efficacious in treating both the physiological and psychological symptoms of chronic pain conditions but the potential of many combined therapies is unknown. This study examined the effects of a combined intervention of mindfulness meditation followed by aerobic walking exercise in chronic low back pain (cLBP) patients. We hypothesized that meditation before exercise would reduce disability and pain by increasing mindfulness prior to physical activity. Thirty-eight adults completed either meditation and exercise treatment (MedExT) (n=18) or an audiobook control condition (n=20). Over a 4-week period, participants in the MedExT group performed 12-17 minutes of guided meditation followed by 30 minutes of moderate intensity walking exercise 5 days per week. Measures of disability, pain, mindfulness and anxiety were taken at baseline and post-intervention. Ratings of pain were also assessed by participant self-report, before and after each intervention session. Following MedExT, participants showed significant improvement in our primary outcome of disability compared to the control group (p

Complex regional pain syndrome (CRPS) is a debilitating chronic pain disorder that is often resistant to traditional treatments and has long-term financial and emotional consequences. Spinal cord stimulation (SCS) has gained popularity over the last few decades for treating many types of chronic pain, and has been shown to significantly improve pain and quality of life in CRPS. Different variations of SCS, including burst and high-frequency stimulation, are equally as effective at reducing pain in patients with CRPS and can achieve this result at subsensory threshold levels. A promising new approach in neuromodulation is dorsal root ganglion stimulation, which is a technique that allows for more precise pain relief in areas that were previously difficult to reach. Advancements in both research and technology have helped make SCS a mainstay in the treatment of CRPS.

International audience; BACKGROUND:Three international surveys were developed aiming to identify the current nutrition educational tools used in the management of phenylketonuria (PKU) and the perceived effectiveness of these tools by clinicians, parents and patients.METHODS:The first two surveys were distributed through the Metabolic Dietitians ListServe (pno-metabl@listserv.cc.emory.edu), and the third survey was distributed by international clinics and the National PKU Alliance website (www.npkua.org). A total of 888 responses (S1, n = 88; S2, n = 81; S3, n = 719) were collected from all three surveys. The surveys represent participants from 17 countries, in Europe; North America (USA and Canada); Mexico; Argentina; Turkey; Australia; and Africa (Tunisia).RESULTS:A consistent decline in 'parents as role models' as an educational tool was observed starting at age 10 years. Patients responded they feel their families are the most effective form of education, whereas handouts were selected as the least effective educational tool by patients. Parents responded they feel the most effective educational tool is one-on-one counselling. Patients and parents show a desirable trend in wanting to attend group clinic, even in centres where this type of educational tool is not offered.CONCLUSIONS:There was a discrepancy between clinicians and patient views regarding the perceived effectiveness of the nutrition education tools. Future research is needed surrounding the impact nutrition education may have on improved dietary compliance in patients with PKU.

Vertebrae are connected through a synovial joint made up of the inferior and superior articulating facets, also referred to as the zygapophyseal joint, and assist in motion of the spine unique to their location within the cervical, thoracic, and lumbar spine. Two medial branches of the dorsal primary rami innervate each specific zygapophyseal joint. Patients with acute facet arthropathy may complain of pain provocation with extension, rotation, and/or axial loading. Typical referral patterns for pain emanating from specific facet joints have been identified and mapped for the cervical, thoracic, and lumbar zygapophyseal joints (Dwyer et al. Spine. 1990; 15(6):453–457; Kellegren. Clin Sci 1939;4:35–46). Treatment may include conservative measures, for example, medications, physical therapy, spinal manipulation, and injections. Standard treatment for acute facet arthropathy-related pain typically includes physical therapy and intra-articular corticosteroid injections and/or radiofrequency ablation of the medial branches that innervate the zygapophyseal joint.

STUDY DESIGN Nonrandomized trial. OBJECTIVE This is an ex vivo study using pork chops to simulate human vertebra to determine the effects of various anesthetic fluids injectates and concentrations on lesion size and shape created when using cooled radiofrequency ablation. Secondary objective is to determine the effects of various time durations of applied lesion on lesion size created. Our final objective is to determine the effects of fluid injectates on tissue temperature and impedance. SUMMARY OF BACKGROUND DATA Radiofrequency neurotomy is a therapeutic procedure involving ablation of sensory afferent nerves to the vertebral zygapophyseal joints. Larger lesions increase the likelihood the target nerve is ablated. METHODS Before cooled radiofrequency ablation, tissue was injected with either 0.9% normal saline, 1% lidocaine, 2% lidocaine, 0.25% bupivacaine, 0.5% bupivacaine, 0.75% bupivacaine, 0.2% ropivacaine, 0.5% ropivacaine, or 1% ropivacaine. Duration of cooled radiofrequency was either 45, 90, or 150 seconds. RESULTS There was no significant difference in the size of the lesion created when using different injectates and concentrations. There was no significant difference in the size of the lesion created when applying a 90 seconds duration lesion compared with a 150 seconds duration lesion. CONCLUSION Applying a 90 seconds duration lesion can be considered in clinical use for cooled radiofrequency ablation. The use of an injectate did not significantly alter the size or desired spherical shape of the lesion created, did not significantly alter the time required to create the lesion, and did not significantly lower the temperature threshold. The study is limited by the use of ex vivo tissue which does not account for the effects of tissue perfusion. The use of an injectate before cooled radiofrequency ablation can be made at the interventionalist's discretion. LEVEL OF EVIDENCE N/A.

Objective For interlaminar cervical epidural steroid injections (CESI) the lateral fluoroscopic view (LAT) is often considered to improve needle localization. However, the contralateral-oblique view (CLO) is a useful alternative with potential advantages to improve identification of cervical anatomy and needle depth assessment. The authors explored the attitudes and perceptions of pain medicine fellows currently training in two ACGME-accredited pain medicine fellowship programs regarding the use of these two types of fluoroscopic views. Methods The survey was conducted online following a request by e-mail. Of a total of 20 fellows who were contacted, there were 17 respondents who had experience with both techniques, and they were included for analysis. Results The response rate for participation was 95%. Whereas 70.6% respondents reported they were very certain about the assessment of anatomy with the CLO view, only 17.6% felt very certain with the LAT view. Compared with learning to perform interlaminar CESI using the LAT view only, the majority of fellows thought that using the CLO technique was easier to learn (P

Objective.—To investigate the high-frequency vestibulo-ocular reflex (VOR) in patients with migraine, with and without dizziness and aura. Background.—Migraine is a common cause of dizziness. Although many vestibular testing abnormalities have been documented in migraine patients, high-frequency VOR abnormalities have not been reported. Methods.—Thirty-nine consecutive patients with migraine were studied with the vestibular autorotation test (VAT®). The patients were subclassified as having migraine headache only, migraine with visual aura, migraine with dizziness, or migraine with visual aura and dizziness. Results.—Only a high vertical phase in the 4 to 5 Hz range was correlated with migraine (correlation coefficients: .356, P= .03). Further analysis revealed that an abnormal 4 to 5 Hz vertical phase result also was positively correlated with migraine with aura and dizziness (correlation coefficients: .392). Conclusion.—The results suggest that patients with migraine may have an abnormal vertical VOR at higher head movement frequencies. Migraine patients with visual aura and dizziness are even more likely to have this abnormality.

Disclosures: R. Nguyen, No Disclosures: I Have No Relevant Financial Relationships to Disclose. Case Description: The patient is a 45-year-old woman who presented with chronic right groin pain that started about 10 years prior. Because she was an avid dancer, she attributed her pain to years of dancing. She saw Orthopaedics and underwent hip and pelvis x-rays which demonstrated preserved joint spaces. She underwent an MR arthrogram of the right hip which showed evidence of fluid accumulating in the right greater trochanteric bursa. There was no evidence of labral tear, occult bony abnormality, muscle tear, or psoas tenosynovitis. She had been through PT, used ice, and NSAIDs. Of note, she had a motor vehicle accident 26 years prior with subsequent spleen rupture and then was diagnosed with ectopic spleen and underwent surgical removal by OB/GYN one year prior. Program Description: Musculoskeletal outpatient center. Setting: Academic Center. Results or Clinical Course: MRI pelvis was obtained showing increased signal overlying the right greater trochanter suggesting trochanter bursitis and gluteal tendinopathy. There was a 5 2 cm intrapelvic globular lesion on the left side of the pelvis and a 2.5 2 cm lesion on the right side of the pelvis. There were other bilateral lower pelvis soft tissue lesions, possibly external iliac adenopathy. She underwent a spleen nuclear scan, which confirmed ectopic spleen. It was felt that the masses were likely the underlying etiology of her pain given the local compression and traction on nearby structures. She saw General Surgery. CT was obtained showing absent spleen and multiple enhancing soft tissue masses, including in the omentum and right pelvic sidewall likely representing splenosis. She was planned for surgical excision with GYN-Oncology and Vascular Surgery given the close proximity to the vascular structures. Discussion: We present an interesting case of splenosis resulting in groin/pelvic pain manifesting many years later. While there have been descriptions of splenosis in the gynecologic and internal medicine literature, this is a unique case in an athlete who first underwent orthopaedic evaluation as symptoms initially suggested hip pathology. Conclusions: When the past medical history includes posttraumatic splenectomy and other workup is unrevealing, symptomatic splenosis should be considered in the differential diagnosis of chronic groin/pelvic pain.

The high performance satellite communications networks of the future will have to be interoperable with terrestrial fiber cables. These satellite networks will evolve from narrowband analogue formats to broadband digital transmission schemes, with protocols, algorithms and transmission architectures that will segment the data into uniform cells and frames, and then transmit these data via larger and more efficient synchronous optional (SONET) and asynchronous transfer mode (ATM) networks that are being developed for the information “superhighway”. These high performance satellite communications and information networks are required for modern applications, such as electronic commerce, digital libraries, medical imaging, distance learning, and the distribution of science data. In order for satellites to participate in these information superhighway networks, it is essential that they demonstrate their ability to: (1) operate seamlessly with heterogeneous architectures and applications, (2) carry data at SONET rates with the same quality of service as optical fibers, (3) qualify transmission delay as a parameter not a problem, and (4) show that satellites have several performance and economic advantages over fiber cable networks.

There has been much recent progress in the use of reclaimed water (treated municipal sewage plant effluent) for use in the cooling circuits of electric utility plants and other industrial facilities. In the greater Los Angeles area, reclaimed water has been used industrially for over 25 years but some major new projects have been initiated in 1995. By using reclaimed water, electric utility generating stations and other industrial facilities can reduce their need for water from higher quality water sources which can then be conserved for other purposes, such as municipal drinking water. This paper presents an overview of the factors required to successfully use reclaimed water as makeup to recirculating cooling systems. The primary focus is on the possible effects on equipment relative to corrosion, deposition and biological fouling and on the required changes in water treatment. Implementation of the use of this water in some new projects began in May 1995. The paper provides some of the latest available results on the use of this water. The pretreatment process for ammonia removal and chlorination practices is also discussed.

Summary Forty-nine patients with fifty fractures of the scaphoid were reviewed more than six months after surgical treatment using the Herbert bone screw. Twenty-nine patients (mainly those with delayed union and non-union) also had bone grafts. The mean period of follow-up was 18.3 months. In 47 patients (94 %) the fracture had definitely or probably united. The three patients whose fractures did not unite had proximal pole fractures with pre-existing avascular necrosis and osteoarthritis. Immediate post-operative mobilisation was possible in thirty patients. Wrist function as measured by grip strength and range of motion was excellent or good in most patients. Twenty patients had proximal pole fractures and their results are analysed separately.

Online science outreach is paradoxically both easy and difficult. While anyone can start a blog and post updates to Twitter, it can be extremely challenging to establish a long-term following and demonstrate solid measures of success. A daunting number of online tools and platforms exist, and choosing where to start can be a difficult task in itself (for an explanation and guide to online tools, see [1]). As practicing scientists who have contributed to the highly visited marine science blog Deep-Sea News (DSN) for up to nine years, we provide guidance on how scientists, who often have minimal excess time and more pressing priorities, can maximally utilize new media tools. Here, we describe ten rules for conducting effective online outreach, so that other scientists can also enjoy the advantages of disseminating their knowledge and expertise through social media.

The minimum /spl beta/ achievable at the interaction point (/spl beta/*) with the current design of the SLC final focus is limited to /spl sim/5 mm by third order optical aberrations, most notably the U/sub 1266/ and U/sub 3466/ terms (using the notation of K. Brown). A new lattice is presented which effectively zeros these terms. The remaining third order terms which accrue from the interleaved sextupole pairs in the chromatic correction section (CCS) can be cancelled by the inclusion of five octupoles (two in the CCS, and three in the final telescope). The resulting final focus system is corrected to third order for any usable range of /spl beta/* (given the constraints on the beam divergence at the interaction point). The potential luminosity obtainable from such a system is also presented. >

The correction of the chromaticity of low-beta insertions in the storage rings is usually made with sextupole lenses in the ring's arcs. When decreasing the beta functions at the insertion point (IP), this technique becomes fairly ineffective, since it fails to properly correct the higher order chromatic aberrations. Here we consider the approach where the chromatic effects of the quadrupole lenses generating low beta functions at the IP are corrected locally with two families of sextupoles, one family for each plane. Each family has two pairs of sextupoles which are located symmetrically on both sides of the IP. The sextupole-like aberrations of individual sextupoles are eliminated by utilizing optics forming a -I transformation between sextupoles in the pair. The optics also includes bending magnets which preserve equal dispersion functions at the two sextupoles in each pair. At sextupoles in one family, the vertical beta function is made large and the horizontal is made small. The situation is reversed in the sextupoles of the other family. The betatron phase advances from the IP to the sextupoles are chosen to eliminate a second order chromatic aberration. The application of the localized chromatic correction is demonstrated using as an example the lattice design for the Low Energy Ring of the SLAC/LBL/LLNL PEP-II B Factory. >

We describe linac protection and a conventional collimation system appropriate for a next linear collider. The linac accelerating structure can be protected from "worst credible failures" by a system of sacrificial spoilers. For the collimation system we consider the effects of transverse wakefields and the transmission, heating, mechanical stress, and edge-scattering properties of scrapers. We require local chromatic correction, scraper survival for two pulses of a mis-steered beam containing 0.5/spl times/10/sup 12/ particles per pulse, average interception capability of 1% of the beam at any scraper, and zero particles incident on the final doublet in the final focus system. We describe emittance dependent limitations of this system and present formulae which determine scraper gaps. Conventional collimation systems appear adequate to collimate the beams of next generation 0.5 and 1.0 TeV c.m. linear colliders. Though we have combined functional units where possible to reduce total length, the length of our lattices for these systems are longer than 1 km per linac. >

It is pointed out that customer surveys concerning documentation usually focus on the end user. However, the needs of customers within an organization, such as development teams, marketing groups, and customer training, must also be incorporated into the document design. Surveying the needs of internal customers and measuring levels of satisfaction provide additional tools for improving the documentation design cycle. >

Strategies for tuning and correcting aberrations that arise as the real Final Focus Test Beam (FFTB) lattice departs from the design lattice are presented. The following beam-based tuning and alignment strategies are examined: quadrupole alignment, quadrupole tuning, sextupole pair alignment and tuning, and stability of CCX, CCY, and final doublet. The tuning of the incoming beam is considered with regard to alpha and beta matching, incoming dispersion, and incoming coupling. >

For future linear colliders, with very small emittances and beam sizes and demanding tolerances on final focus system alignment and magnet errors, it becomes increasingly important to use the beam as a diagnostic tool. A report is presented on procedures that will be implemented in the Final Focus Test Beam at SLAC (Stanford Linear Accelerator Center) incorporating (i) quadrupole strength changes, (ii) central orbit modifications, (iii) spot size measurements, and (iv) beam stability monitoring. >

A review is presented of the tolerances associated with the Final Focus Test Beam (FFTB). The authors have computed the acceptability window of the input beam for orbit jitter, emittance beta function mismatch, incoming dispersion and coupling; tolerances on magnet alignment, strength and multipole content; and the initial tunability capture of the line. >

A possible collimation scheme is presented for a TeV linear collider which employs mechanical collimation for the horizontal plane and nonlinear collimation (scheme with skew sextupole pairs) for the vertical. This design satisfies all of the requirements imposed on collimation systems, including effective collimation of transverse energy tails, control of wakefield effects, protection of scrapers, and control of geometric and chromatic aberrations. The stability tolerances at the scrapers and sextupoles are similar to those occurring in the NLC (nonlinear collimation) final focus system; given the precision of the beam position monitors envisioned for an NLC, these tolerances should not rule out nonlinear collimation as a candidate for beam scraping in a future linear collider. >

In order to specify the relationship between pictures and their meaning, a class of declarative, constraint-based picture specification languages is introduced. These extend previous approaches to picture specification based on constraints and grammar formalisms. As the languages are defined as an abstract language scheme, it is ensured that they share a common declarative semantics and execution model. The declarative semantics allows both people and machines to easily reason about a specification independently of any underlying implementation. The operational semantics permit a picture specification to be used to both generate and recognize pictures defined by visual languages. Implementation techniques developed for constraint logic programs, which enable this to be done efficiently, are discussed. >

In many electronics/telecommunication applications, switching/signal-processing equipment is commonly placed in outdoor cabinets. The housed equipment generates heat that is while keeping the air temperature inside the cabinets within prescribed limits for optimum performance. Furthermore, the enclosure, being outdoors, receives full solar irradiation, creating an extra heat load that must be handled. Although most cabinets are sufficiently large to allow for active cooling systems, smaller cabinets must meet thermal requirements by passive means only, thus imposing unique restrictions. One way to effect such requirements is to use natural convection and solar radiation shields. The focus of this paper is to present results on experimental and numerical studies used in the design, development and testing of an outdoor cabinet that would operate in full solar loads without the input of power. The cabinet features a unique natural convection heat sink that is shrouded for higher efficiency. This heat sink was especially designed by Teltrend and MJM Engineering to meet the thermal requirements for the cabinet. The enclosure was fully simulated using Icepak/sup TM/, a CFD software package by Fluent, Inc., to ascertain the thermal performance of the heat sink and that the cabinet met thermal requirements. In house tests were conducted using simulated solar loads in a temperature-controlled chamber to corroborate the CFD simulations and the thermal design. Results show that the heat sink effectively removes the heat from the cabinet without using fans. Furthermore, the cabinet as a whole meets the thermal requirement.

An optimization scheme for final focus systems is discussed and applied to the NLC design. The optical functions at the defocusing sextupoles, the sextupole strength, and the length of the system must obey eight conditions that are imposed by the spot size increase due to higher-order aberrations, the effects of synchrotron radiation in the bending magnets, power supply ripple, magnet vibration tolerances, and the estimated orbit stability at the sextupoles. These eight conditions determine the minimum optimum length of the system. The NLC final focus design was shortened to this optimum.

Ten adults were studied two to seven years after resection of a fibula for use as a free vascularised bone graft. Six had no symptoms in the donor leg, four had some aching, weakness or paraesthesia and three had definite weakness of the long toe flexors and extensors. All knees and ankles were clinically and radiologically stable, but the distal fibular remnant was osteoporotic in nine patients. Gait analysis of the donor leg and the contralateral normal leg showed definite differences, which could be attributed to weakness of the deep muscles caused by loss of their normal origin and to the change in load transmission through the fibula.

The results are presented of 47 compression arthrodeses of the ankle performed for osteoarthritis in 44 patients. In 26 cases the transverse anterior incision of Charnley had been used and in 21 cases medial and lateral incisions with division of the malleoli. Complications included infection (19%), non-union (14.9%) and malposition requiring a further procedure (8.5%). Three patients (6.4%) eventually had an amputation. Clinical assessment using a standard grading method showed that the functional result was not related to the angle of plantar flexion of the ankle, but was related to the varus/valgus position of the heel, the neutral position being associated with the best results. The anterior approach was more reliable in avoiding varus or valgus of the heel.

Satellite communications will have an important role in the Global Information Infrastructure (Gil) to complement, restore and even compete with terrestrial networks. Future global communications links will move from circuit switched analog voice to frame and cell switched digital voice, video and data packeted together in a multimedia format and transmitted over high data rate networks. These new broadbandnetworks are being demonstrated by NASA's ACTS satellite, using Ka-bandfrequencies, to show the ability to transmit data at rates and with the quality of service currently delivered by fiber-optic cables. A number of U.S. national and international experiments using government and commercial satellites and fiberoptic cables are currently being conducted to test the seamless interoperability of satellite and terrestrial communications links. These tests indicate the need for compatible standards and protocols to be developed first in a testbed, then in a commercial infrastructure for future global, heterogeneous networks. BACKGROUND

Developing a lattice that contains a very low beta value at the interaction point (IP) and has adequate dynamic aperture is one of the major challenges in designing the PEP-II asymmetric B-factory. For the Low Energy Ring (LER) we have studied several different chromatic correction schemes since the conceptual design report (CDR). Based on these studies, a hybrid solution with local and semi-local chromatic sextupoles has been selected as the new baseline lattice to replace the local scheme in the CDR. The new design simplifies the interaction region (IR) and reduces the number of sextupoles in the arcs. Arc sextupoles are paired at /spl pi/ phase difference and are not interleaved. In this paper we describe the baseline lattice with the emphasis on the lattice changes made since the CDR.

In order to optimize tunability and backgrounds in linear collider final focus systems, it is necessary to align strong quadrupole and sextupole magnets with beam-based measurements. Algorithms for alignment have been used successfully on the Final Focus Test Beam (FFTB) beamline at SLAC. Quadrupole magnets were aligned using a shunt technique, with resolutions from 50 microns down to 700 nanometers. Sextupole magnets were aligned by moving the magnets transverse to the beam and observing the kick on downstream beam position monitors. This procedure resulted in sextupole misalignment resolutions of 5 to 20 microns. All magnets were then moved into aligned positions via remote-controlled stages capable of sub-micron resolution. Details of the fitting algorithms, results of the measurement, and potential improvements in the system are discussed.

In order to reduce the SLAC 46.6 GeV beam to submicron sizes, the Final Focus Test Beam (FFTB) must meet tight tolerances on many aberrations. These aberrations include: mismatch and coupling of the incoming beam; dispersion; chromaticity; lattice errors in the chromatic correction sections; lattice coupling; and residual sextupole content in the quadrupoles. In order to address these aberrations, we have developed a procedure which combines trajectory analysis, use of intermediate wire scanners, and a pair of novel beam size monitors at the IP. This procedure allows the FFTB IP spot to be reduced to sizes under 100 nanometers.