A tungsten external heater for BX90 diamond anvil cells with a range up to 1700 K.

Resistive heating of a sample in a diamond anvil cell (DAC) can generate a homogeneous temperature field across the sample chamber with reliable temperatures measured by a thermocouple. It is of importance in experiments aiming at exploring phase diagrams and quantifying thermoelastic properties of materials. Here, we present a ring-heater design developed for BX90 diamond anvil cells (DACs). It is made of a ring-shaped aluminum oxide holder hosting a tungsten wire coil inside and coupled with Ar + 2% H2 gas to prevent oxidation during experiment. This modular plug-and-play design enables in situ studies of samples via x-ray diffraction up to a temperature of 1700 K. Temperature in the BX90 sample volume as measured through a thermocouple was calibrated using the melting point of gold. As an application of this design, we report the thermal expansion coefficient of MgO at 9.5(1) GPa.

Hartmann characterization of the PEEM-3 aberration-corrected X-ray photoemission electron microscope.

Aberration correction by an electron mirror dramatically improves the spatial resolution and transmission of photoemission electron microscopes. We will review the performance of the recently installed aberration corrector of the X-ray Photoemission Electron Microscope PEEM-3 and show a large improvement in the efficiency of the electron optics. Hartmann testing is introduced as a quantitative method to measure the geometrical aberrations of a cathode lens electron microscope. We find that aberration correction leads to an order of magnitude reduction of the spherical aberrations, suggesting that a spatial resolution of below 100 nm is possible at 100% transmission of the optics when using x-rays. We demonstrate this improved performance by imaging test patterns employing element and magnetic contrast.

Coded aperture imaging for fluorescent x-rays.

We employ a coded aperture pattern in front of a pixilated charge couple device detector to image fluorescent x-rays (6-25 KeV) from samples irradiated with synchrotron radiation. Coded apertures encode the angular direction of x-rays, and given a known source plane, allow for a large numerical aperture x-ray imaging system. The algorithm to develop and fabricate the free standing No-Two-Holes-Touching aperture pattern was developed. The algorithms to reconstruct the x-ray image from the recorded encoded pattern were developed by means of a ray tracing technique and confirmed by experiments on standard samples.

Corynebacterium septic arthritis of the knee presenting as a ruptured septic popliteal cyst.

A rare case of a septic knee arthritis presenting as an infected ruptured popliteal cyst is described. Infection of a popliteal cyst is an uncommon complication of septic arthritis and presentation can mimic that of an acute deep vein thrombosis, leading to delay in diagnosis and treatment. Of interest, the typical hallmarks of infection and haematological markers of inflammation were all unremarkable in the current case. This case was of additional interest in that there have been no reports in the literature of Corynebacterium spp. being isolated from an infected popliteal cyst. Invasive infections caused by Corynebacterium spp. seem to have a predilection for patients who are immunocompromised. It is especially important in this subset of patients that delays in diagnosis are avoided by including it in the differential of an immunocompromised patient presenting with unilateral lower-extremity pain and swelling.

Fracture of two successive Ring TiMESH cemented hip prostheses.

We report the unfortunate case of a man who experienced stem failures of both his primary and revision hip arthroplasties. As far as we are aware this is the only reported case of a patient to suffer the misfortune of multiple femoral implant failures.

Is epidural anaesthesia acceptable at total hip arthroplasty? A study of the rates of urinary catheterisation.

Epidural anaesthesia, with and without opiate, is widely used in total hip arthroplasty (THA). It may cause urinary retention, leading to catheterisation, and a subsequent increase in the likelihood of deep infection. We investigated prospectively the rate of urinary catheterisation in patients after THA performed under general anaesthesia, with or without peri-operative fentanyl and bupivacaine opiate epidural anaesthesia. Of 173 patients, 75 received general anaesthesia alone and 98 both general and epidural management. The post-operative rate of catheterisation was 14.7% in those who received general anaesthesia alone and 13.3% in those who received both. Our findings suggest that the rate of post-operative urinary catheterisation does not increase when general anaesthesia is supplemented by epidural anaesthesia using fentanyl and bupivicaine.

Shear at twin domain boundaries in YBa2Cu3O7-x.

The microstructure and strain state of twin domains in YBa2Cu3O7-x are discussed based upon synchrotron white-beam x-ray microdiffraction measurements. Intensity variations of the fourfold twin splitting of Laue diffraction peaks are used to determine the twin domain structure. Strain analysis shows that interfaces between neighboring twin domains are strained in shear, whereas the interior of these domains are regions of low strain. These measurements are consistent with the orientation relationships of twin boundaries within and across domains and show that basal plane shear stresses can exceed 100 MPa where twin domains meet. Our results support stress field pinning of magnetic flux vortices by twin domain boundaries.

Local plasticity of Al thin films as revealed by x-ray microdiffraction.

Grain-to-grain interactions dominate the plasticity of Al thin films and establish effective length scales smaller than the grain size. We have measured large strain distributions and their changes under plastic strain in 1.5-microm-thick Al 0.5% Cu films using a 0.8-microm-diameter white x-ray probe at the Advanced Light Source. Strain distributions arise not only from the distribution of grain sizes and orientation, but also from the differences in grain shape and from stress environment. Multiple active glide plane domains have been found within single grains. Large grains behave like multiple smaller grains even before a dislocation substructure can evolve.

Scanning X-ray microdiffraction with submicrometer white beam for strain/stress and orientation mapping in thin films.

Scanning X-ray microdiffraction (microSXRD) combines the use of high-brilliance synchrotron sources with the latest achromatic X-ray focusing optics and fast large-area two-dimensional-detector technology. Using white beams or a combination of white and monochromatic beams, this technique allows for the orientation and strain/stress mapping of polycrystalline thin films with submicrometer spatial resolution. The technique is described in detail as applied to the study of thin aluminium and copper blanket films and lines following electromigration testing and/or thermal cycling experiments. It is shown that there are significant orientation and strain/stress variations between grains and inside individual grains. A polycrystalline film when investigated at the granular (micrometer) level shows a highly mechanically inhomogeneous medium that allows insight into its mesoscopic properties. If the microSXRD data are averaged over a macroscopic range, results show good agreement with direct macroscopic texture and stress measurements.

Cemented or uncemented hemiarthroplasty for displaced intracapsular femoral neck fractures.

The aim of this study was to establish whether or not to cement the hemiarthroplasty for displaced intracapsular femoral neck fractures in the elderly. Consecutive patients treated by hemiarthroplasty in adjacent hospitals were reviewed. The same monoblock prosthesis was used; in hospital A they were uncemented (121 patients), and in hospital B they were cemented (123 patients). Notes were reviewed retrospectively. Surviving patients (50 and 56 respectively) were assessed prospectively for pain and functional ability using validated scoring systems. Follow-up was 32-36 months. Patient demographics were similar. Fewer of the cemented group had been revised or were awaiting revision ( P=0.036). There was no difference in general complication or mortality rates. There was a highly statistically significant greater deterioration in pain ( P=0.003), walking ability ( P=0.002), use of walking aids ( P=0.003) and activities of daily living ( P=0.009) in the uncemented group. Our findings support the use of cemented hemiarthroplasty in the elderly.

A survey of the treatment of displaced intracapsular femoral neck fractures in the UK.

A survey was undertaken to investigate the treatment of displaced intracapsular femoral neck fractures across the UK. The usual practice at 223 hospitals was recorded for two groups of patients, active and frail. Management of stereotyped fractures, in similar patients, varied between hospitals. There was also variation between specialists within some hospitals: two or more of the alternative methods of treatment were in routine use for active patients at 22% of hospitals and for frail patients at 27%. Overall, for active patients, bipolar hemiarthroplasty was undertaken at 41% of hospitals, internal fixation at 37%, unipolar hemiarthroplasty at 32% and total hip replacement at 16%. Cemented prostheses were used in 74% of arthroplasties for active patients. For frail patients, hemiarthroplasty with an Austin Moore or Thompson prostheses was undertaken at 94% of hospitals; bipolar prostheses were used at 8%; internal fixation was undertaken at 1%. Cement was used in 46% of hemiarthroplasties. These findings indicate a lack of consensus in aspects of the treatment of displaced intracapsular femoral neck fractures and are likely to reflect difficulties in determining "best practice."

Cemented or uncemented hemiarthroplasty for displaced intracapsular fractures of the hip--a systematic review.

Displaced intracapsular hip fractures are often treated by hemiarthroplasty, with or without cement. The aim of this study is to perform a systematic review of the literature to establish whether this influences the outcome. A comprehensive search of the English language world literature of all studies comparing cemented with uncemented hemiarthroplasty was performed. Eighteen publications addressing this issue were identified. Three were excluded from review because of poor study design and non-comparability of groups. Of the remainder, few were suitable for statistical analysis, therefore a qualitative comparison of results was carried out. The majority of studies suggested a lower revision rate, less thigh pain and better mobility in-patients in whom the prosthesis was cemented. Cemented hemiarthroplasty may be associated with increased operative time and blood loss. There appears to be no difference in general complication, or mortality rates after 3 months, between the two groups. Radiographic differences were variable and did not correlate with clinical findings. We conclude, the literature tends to support the use of cement in hemiarthroplasty for displaced intracapsular femoral neck fractures. Further prospective randomised studies are required to resolve the issue.

Effect of topical povidone-iodine versus topical ofloxacin on experimental Staphylococcus keratitis.

PURPOSE: To compare the antibacterial effect of povidone-iodine (PI) with that of ofloxacin in an experimental model of bacterial keratitis. METHODS: Staphyloccocal keratitis was induced in 21 eyes of Dutch Belted rabbits by intrastromal inoculation of approximately 280 organisms of Staphylococcus aureus. Six hours later, the animals were divided in four groups treated topically with saline 0.9%, Betadine 10%, Betadine 0.5% or Ofloxacin 0.3% (2 gtt every 30 min for 8 h). The central 8-mm cornea was excised, washed and homogenized. Colony counts were performed on serial 10-fold dilutions plated on blood and brain infusion agar and incubated overnight. RESULTS: Colony-forming units per cornea were 7.4x10(7) for the saline group compared to 8.2x10(7) for PI 10% (P>0.5), 4.3x10(7) for PI 0.5% (P<0.01) and no organisms for ofloxacin 0.3%. CONCLUSIONS: Betadine 0.5% demonstrates a statistically significant bactericidal effect compared with untreated staphyloccocal keratitis in our experimental model. Ofloxacin has superior antibacterial effect under the conditions studied. Further improvements in the povidone-iodine formulation are warranted prior to consideration for human keratitis.

Characterization of conditions required for X-Ray diffraction experiments with protein microcrystals.

The x-ray exposure at which significant radiation damage occurs has been quantified for frozen crystals of bacteriorhodopsin. The maximum exposure to approximately 11-keV x-rays that can be tolerated for high-resolution diffraction experiments is found to be approximately 10(10) photons/microm(2), very close to the value predicted from limits that were measured earlier for electron diffraction exposures. Sample heating, which would further reduce the x-ray exposure that could be tolerated, is not expected to be significant unless the x-ray flux density is well above 10(9) photons/s-microm(2). Crystals of bacteriorhodopsin that contain approximately 10(11) unit cells are found to be large enough to give approximately 100 high-resolution diffraction patterns, each covering one degree of rotation. These measurements are used to develop simple rules of thumb for the minimum crystal size that can be used to record x-ray diffraction data from protein microcrystals. For work with very small microcrystals to be realized in practice, however, it is desirable that there be a significant reduction in the level of background scattering. Background reduction can readily be achieved by improved microcollimation of the x-ray beam, and additional gains can be realized by the use of helium rather than nitrogen in the cold gas stream that is used to keep the protein crystals frozen.

Therapeutic effects of oral NADH on the symptoms of patients with chronic fatigue syndrome.

BACKGROUND: Chronic fatigue syndrome (CFS) is a disorder of unknown etiology, consisting of prolonged, debilitating fatigue, and a multitude of symptoms including neurocognitive dysfunction, flu-like symptoms, myalgia, weakness, arthralgia, low-grade fever, sore throat, headache, sleep disturbances, and swelling and tenderness of lymph nodes. No effective treatment for CFS is known. OBJECTIVE: The purpose of the study was to evaluate the efficacy of the reduced form of nicotinamide adenine dinucleotide (NADH) i.e., ENADA the stabilized oral absorbable form, in a randomized, double-blind, placebo-controlled crossover study in patients with CFS. Nicotinamide adenine dinucleotide is known to trigger energy production through ATP generation which may form the basis of its potential effects. METHODS: Twenty-six eligible patients who fulfilled the Center for Disease Control and Prevention criteria for CFS completed the study. Medical history, physical examination, laboratory studies, and questionnaire were obtained at baseline, 4, 8, and 12 weeks. Subjects were randomly assigned to receive either 10 mg of NADH or placebo for a 4-week period. Following a 4-week washout period, subjects were crossed to the alternate regimen for a final 4-week period. RESULTS: No severe adverse effects were observed related to the study drug. Within this cohort of 26 patients, 8 of 26 (31%) responded favorably to NADH in contrast to 2 of 26 (8%) to placebo. Based upon these encouraging results we have decided to conduct an open-label study in a larger cohort of patients. CONCLUSION: Collectively, the results of this pilot study indicate that NADH may be a valuable adjunctive therapy in the management of the chronic fatigue syndrome and suggest that further clinical trials be performed to establish its efficacy in this clinically perplexing disorder.

A novel delivery system for continuous desferrioxamine infusion in transfusional iron overload.

Fifteen iron-overloaded thalassaemia major (TM) patients and two homozygous sickle cell patients (SCD) were treated continuously for 7d each week with the novel 48 h continuous subcutaneous (s.c.) desferrioxamine (DFX) delivery device (code C1083, Baxter) and 10 TM patients received the 24 h continuous intravenous (i.v.) DFX delivery device (code C1071). The 27 patients had previously received conventional s.c. DFX for 8-10h on 5 or more days each week. The serum non-transferrin bound iron (NTBI) levels fell significantly in both groups within 12h of commencing the continuous infusion. In the s.c. group the mean level fell from 4.2 to 2.0 mumol/l (P = 0.001), whereas in the i.v. group the mean level fell from 3.6 to 0.1 mumol/l (P = 0.006) the initial levels being measured 12h after stopping conventional s.c. DFX. After 4 weeks there was a significant fall in serum ferritin in both groups (P = 0.009). The new DFX delivery device is effective at removing toxicfree iron from plasma and reducing body iron. Moreover, it is preferred by patients with much improved compliance compared to the conventional s.c. DFX pump.

Synchrotron radiation sources and condensers for projection x-ray lithography.

The design requirements for a compact electron storage ring that could be used as a soft-x-ray source for projection lithography are discussed. The design concepts of the x-ray optics that are required for collecting and conditioning the radiation in divergence, uniformity, and direction to illuminate the mask correctly and the particular x-ray projection camera used are discussed. Preliminary designs for an entire soft-x-ray projection lithography system that uses an electron storage ring as a soft-x-ray source are presented. It is shown that, by combining the existing technology of storage rings with large collection angle condensers, a powerful and reliable source of 130-A photons for production line projection x-ray lithography is possible.

Mask technologies for soft-x-ray projection lithography at 13 nm.

We describe a variety of technologies for patterning transmissive and reflective soft x-ray projectionlithography masks containing features as small as 0.1 µm. The transmission masks fabricated for use at 13 nm are of one type, a Ge-absorbing layer patterned on a boron-doped Si membrane. Reflective masks were patterned by various methods that included absorbing layers formed on top of multilayer reflectors, multilayer-reflector-coating removal by reactive ion etching, and ion damage of multilayer regions by ion implantation. For the first time, we believe, a process for absorber repair that does not significantly damage the reflectance of the multilayer coating on the reflection mask is demonstrated.

Characterization of AZ PN114 resist for soft-x-ray projection lithography.

Using 14-nm wavelength illumination, we have imaged 0.1-µm-wide lines and spaces in single-layer thin films of the highy sensitive, negative, chemically amplified resist AZ PN114 by usingboth a Schwarzschild 20× camera and an Offner ring field 1× optical system. For soft-x-ray projection lithography the approximate 0.2-µm absorption length in resists at 14-nm wavelength necessitates a multilayer resist system. To explore further the requirements of the imaging layer of such a system, we have transferred patterns, exposed by a high-resolution electron beam in a 60-nm-thick layer of AZ PN114, into the underlying layers of a trilevel structure. Significant pattern edge noise and resist granularity were found. It remains to be determined whether the observed noise is dominated by statistical fluctuations in dose or by resist chemistry. We also investigated pinhole densities in these films and found them to increase from 0.2 cm(-2) for 380-mm-thick films to 15 cm(-2) for 50-nm-thick films.