Structural and magnetic studies of the frustratedS = 1 kagome magnet NH4Ni2Mo2O10H3

The strong geometric frustration of the kagome antiferromagnets (KAFMs) can destabilise conventional magnetic order and lead to exotic electronic states, such as the quantum spin-liquid state observed in someS=12KAFM materials. However, the ground state ofS = 1 KAFM systems are less well understood. Spin nematic phases and valence bond solid ground states have been predicted to form but a paucity of experimental realisations restricts understanding. Here, theS = 1 KAFM NH4Ni2Mo2O10H3is presented, which has the 3-fold symmetry of the kagome lattice but significant site depletion, with∼64%site occupancy. Frustration and a competition between exchange interactions are evidenced through the suppression of order below the Weiss temperature|θW|and observation of ferromagnetic and antiferromagnetic characteristics in the magnetisation data. A semi spin glass ground state is predicted based on the ac-field frequency dependence of the magnetic transition and ferromagnetic signal.

1138 Complete Cycle Audit of Adults with Incapacity Documentation

Aim

The Adults with Incapacity (Scotland) Act 2000 sets out the framework for regulating intervention in the affairs of adults who have impaired capacity. A certificate of incapacity should be completed for those deem incapable to decide on their medical treatment. We aim to improve the accuracy of adults with incapacity documentation to 90% over 6 months period and

Method

Data was collected over three months, focusing on 3 domains:

The results of first cycle were discussed on the departmental meeting. Education flyers were sent to everyone in the department and put up in the doctors’ room. Data was collected again after 6 months with the same inclusion criteria.

Results

The percentage of patients with a patient with incapacity certificate has dropped to 34% from 50%. Completion of capacity assessment remained 100%. Attempt to contact relevant others has increased from 52% to 92%. Accuracy of documentation has improved to 77% from 44%.

Conclusions

The proportion of patients with a patient with incapacity certificate is in keeping with the prevalence of delirium in surgical wards. Interactive discussion and flyers improve compliances with completion of adult with incapacity certificate. Routine training should be included in departmental teaching to ensure future compliances.

[Effects of remote ischemic preconditioning on contrast-induced acute kidney injury after percutaneous coronary intervention in patients with chronic total occlusion]

Objective: To investigate the effect of remote ischemic preconditioning (RIPC) on contrast-induced acute kidney injury (CI-AKI) in patients with chronic total occlusion (CTO) after percutaneous coronary intervention (PCI). Methods: A total of 282 patients undergoing PCI at Zhongda Hospital Affiliated to Southeast University between June 2017 and January 2019 were prospectively enrolled. The patients were randomly divided into RIPC group (n=142) and control group (n=140). CI-AKI was defined as an increase in level of cystatin C (CysC)≥10% above baseline at 24 h after contrast administration. Baseline characteristics and the incidence of CI-AKI were compared between the two groups. The multivariate logistic regression analysis was further used to analyze the independent risk factors of CI-AKI. Results: There were no significant differences in age, gender, smoking, hypertension, diabetes, stroke and old myocardial infarction, coronary artery bypass graft surgery, previous PCI history and laboratory test indicators, target vessel and pathological characteristics of CTO lesions, contrast agent dosage, J-CTO (Multicenter CTO Registry in Japan) score, SYNTAX (Synergy between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery) score, PCI success rate and stent number between the two groups (P>0.05). The incidence of CI-AKI was significantly lower (18.3% vs 29.3%, P=0.036) in RIPC group than that of control group. Multivariate logistic analysis found that creatinine [odds ratio (OR)=1.018,95%CI: 1.006-1.030, P=0.003], CysC (OR=5.200, 95%CI:2.714-9.963, P<0.001),contrast agent dosage (OR=1.013,95%CI: 1.007-1.019, P<0.001) and J-CTO score (OR=1.834, 95%CI: 1.145-2.939, P=0.012) were independent risk factors of CI-AKI. However, RIPC was an independent protective factor of CI-AKI (OR=0.391, 95%CI: 0.199-0.765, P=0.006). Conclusion: RIPC before contrast agent administration prevents CI-AKI in CTO patients undergoing PCI.

Accelerated diversification correlated with functional traits shapes extant diversity of the early divergent angiosperm family Annonaceae

A major goal of phylogenetic systematics is to understand both the patterns of diversification and the processes by which these patterns are formed. Few studies have focused on the ancient, species-rich Magnoliales clade and its diversification pattern. Within Magnoliales, the pantropically distributed Annonaceae are by far the most genus-rich and species-rich family-level clade, with c. 110 genera and c. 2,400 species. We investigated the diversification patterns across Annonaceae and identified traits that show varied associations with diversification rates using a time-calibrated phylogeny of 835 species (34.6% sampling) and 11,211 aligned bases from eight regions of the plastid genome (rbcL, matK, ndhF, psbA-trnH, trnL-F, atpB-rbcL, trnS-G, and ycf1). Twelve rate shifts were identified using BAMM: in Annona, Artabotrys, Asimina, Drepananthus, Duguetia, Goniothalamus, Guatteria, Uvaria, Xylopia, the tribes Miliuseae and Malmeeae, and the Desmos-Dasymaschalon-Friesodielsia-Monanthotaxis clade. TurboMEDUSA and method-of-moments estimator analyses showed largely congruent results. A positive relationship between species richness and diversification rate is revealed using PGLS. Our results show that the high species richness in Annonaceae is likely the result of recent increased diversification rather than the steady accumulation of species via the 'museum model'. We further explore the possible role of selected traits (habit, pollinator trapping, floral sex expression, pollen dispersal unit, anther septation, and seed dispersal unit) in shaping diversification patterns, based on inferences of BiSSE, MuSSE, HiSSE, and FiSSE analyses. Our results suggest that the liana habit, the presence of circadian pollinator trapping, androdioecy, and the dispersal of seeds as single-seeded monocarp fragments are closely correlated with higher diversification rates; pollen aggregation and anther septation, in contrast, are associated with lower diversification rates.

In situ study of sigma phase formation in Cr-Co-Ni ternary alloys at 800°C using the long duration experiment facility at Diamond Light Source

The new long duration experiment facility on beamline I11 at Diamond Light Source has been used to study the kinetics of sigma phase formation in three Cr-Co-Ni alloys. Diffraction data acquired during in situ exposure at 800°C for 50 d showed progressive increases in the sigma fraction. This was accompanied by changes in the proportions of the other phases, which differed markedly between the alloys studied. These results demonstrate the capabilities of the long duration facility for the study of metallurgical phenomena over periods of months to years, a capability not previously available at a synchrotron source.

Temperature-induced polymorphism in methyl stearate

Different temperature conditions can induce different crystallisation behaviours of methyl stearate. Three new polymorphs have been identified and structural characterised.

Processing two-dimensional X-ray diffraction and small-angle scattering data in DAWN 2

The Powder Calibration and Processing packages implemented in DAWN 2 provide an automated diffraction-geometry calibration and data processing environment for two-dimensional diffraction experiments. The customizable processing chains permit the execution of data processing steps to convert raw two-dimensional data into meaningful data and diffractograms. The provenance of the processed data is maintained, which guarantees reproducibility and transparency of the data treatment.

A software package for the calibration and processing of powder X-ray diffraction and small-angle X-ray scattering data is presented. It provides a multitude of data processing and visualization tools as well as a command-line scripting interface for on-the-fly processing and the incorporation of complex data treatment tasks. Customizable processing chains permit the execution of many data processing steps to convert a single image or a batch of raw two-dimensional data into meaningful data and one-dimensional diffractograms. The processed data files contain the full data provenance of each process applied to the data. The calibration routines can run automatically even for high energies and also for large detector tilt angles. Some of the functionalities are highlighted by specific use cases.

Structural phase transitions in the kagome lattice based materials Cs2−xRbxSnCu3F12 (x = 0, 0.5, 1.0, 1.5)

The system Cs_2−xRb_xSnCu₃F₁₂ exhibits several different distorted variants of the kagome lattice, which are probed in detail by powder diffraction methods.

Low-temperature Debye–Scherrer powder diffraction on Beamline I11 at Diamond

A bespoke capillary sample holder is described that attaches to the cold head of a commercially manufactured (PheniX) closed-cycle helium cryostat originally intended for flat-plate geometry. The new holder allows high-resolution synchrotron powder diffraction data to be collected from samples in Debye–Scherrer geometry over the temperature range 11–295 K. To demonstrate that high-quality powder data can be obtained using this new sample holder, structural refinement (Rietveld) and thermal expansion results measured from reference samples (Si and Al) are presented.

Network correlates of disease severity in multiple system atrophy

OBJECTIVE

Multiple system atrophy (MSA), the most common of the atypical parkinsonian disorders, is characterized by the presence of an abnormal spatial covariance pattern in resting state metabolic brain images from patients with this disease. Nonetheless, the potential utility of this pattern as a MSA biomarker is contingent upon its specificity for this disorder and its relationship to clinical disability in individual patients.

METHODS

We used [(18)F]fluorodeoxyglucose PET to study 33 patients with MSA, 20 age- and severity-matched patients with idiopathic Parkinson disease (PD), and 15 healthy volunteers. For each subject, we computed the expression of the previously characterized metabolic covariance patterns for MSA and PD (termed MSARP and PDRP, respectively) on a prospective single-case basis. The resulting network values for the individual patients were correlated with clinical motor ratings and disease duration.

RESULTS

In the MSA group, disease-related pattern (MSARP) values were elevated relative to the control and PD groups (p < 0.001 for both comparisons). In this group, MSARP values correlated with clinical ratings of motor disability (r = 0.57, p = 0.0008) and with disease duration (r = -0.376, p = 0.03). By contrast, MSARP expression in the PD group did not differ from control values (p = 1.0). In this group, motor ratings correlated with PDRP (r = 0.60, p = 0.006) but not with MSARP values (p = 0.88).

CONCLUSIONS

MSA is associated with elevated expression of a specific disease-related metabolic pattern. Moreover, differences in the expression of this pattern in patients with MSA correlate with clinical disability. The findings suggest that the MSARP may be a useful biomarker in trials of new therapies for this disorder.

A high-resolution synchrotron powder diffraction study of substituted gallium ferrites using flat-plate fixed angle of incidence geometry on beamline I11 at Diamond

Very high resolution powder diffraction structural studies of the potentially room temperature multiferroic Ga2−xFexO3solid solution series (x= 0.7–1.3, 0.1 steps) have been undertaken using a fixed angle of incidence geometry. The applied absorption correction was seen to improve the goodness of fit (χ2) of the Rietveld refinements from an average of 1.41 to 1.06. The correction also resulted in an increased mean isotropic displacement parameter from 0.5 to 0.65. The mean difference in the fractional coordinates of the atoms between the refined models from the corrected and uncorrected data was 0.0007 Å, compared with the mean fractional coordinate error of 0.0003 Å. It is concluded that the final crystal structures refined from the corrected and uncorrected data are not significantly different. The number of reflections in each data set was over 2700, and the average peak half-width was 0.018° with the data binned in 4 millidegree steps. The data quality allowed bond length and angle determinations of sufficiently high accuracy to measure significant metal site distortions to an average precision of ±0.007 Å. A lattice parameter nonlinearity was observed on either side of thex= 1 composition; this was attributed to local distortions, primarily of the Fe1 and Ga2 sites.

Network correlates of the cognitive response to levodopa in Parkinson disease

OBJECTIVE

Cognitive dysfunction is common in Parkinson disease (PD), even early in its clinical course. This disease manifestation has been associated with impaired verbal learning performance as well as abnormal expression of a specific PD-related cognitive spatial covariance pattern (PDCP). It is not known, however, how this metabolic network relates to the cognitive response to dopaminergic therapy on the individual patient level.

METHODS

We assessed treatment-mediated changes in verbal learning and PDCP expression in 17 patients with PD without dementia who underwent cognitive testing and metabolic imaging in the unmedicated and levodopa-treated conditions. We also determined whether analogous changes were present in 12 other patients with PD without dementia who were evaluated before and during the treatment of cognitive symptoms with placebo.

RESULTS

Levodopa-mediated changes in verbal learning correlated with concurrent changes in PDCP expression (r = -0.60, p < 0.01). The subset of patients with meaningful cognitive improvement on levodopa (n = 8) exhibited concurrent reductions in PDCP expression (p < 0.01) with treatment; network modulation was not evident in the remaining subjects. Notably, the levodopa cognitive response correlated with baseline PDCP levels (r = 0.70, p = 0.002). By contrast, placebo did not affect PDCP expression, even in the subjects (n = 7) with improved verbal learning during treatment.

CONCLUSIONS

These findings suggest that cognitive dysfunction in PD may respond to treatment depending upon the degree of baseline PDCP expression. Quantification of treatment-mediated network changes can provide objective information concerning the efficacy of new agents directed at the cognitive manifestations of this disease.

Abnormal metabolic brain networks in Tourette syndrome

OBJECTIVES

To identify metabolic brain networks that are associated with Tourette syndrome (TS) and comorbid obsessive-compulsive disorder (OCD).

METHODS

We utilized [(18)F]-fluorodeoxyglucose and PET imaging to examine brain metabolism in 12 unmedicated patients with TS and 12 age-matched controls. We utilized a spatial covariance analysis to identify 2 disease-related metabolic brain networks, one associated with TS in general (distinguishing TS subjects from controls), and another correlating with OCD severity (within the TS group alone).

RESULTS

Analysis of the combined group of patients with TS and healthy subjects revealed an abnormal spatial covariance pattern that completely separated patients from controls (p < 0.0001). This TS-related pattern (TSRP) was characterized by reduced resting metabolic activity of the striatum and orbitofrontal cortex associated with relative increases in premotor cortex and cerebellum. Analysis of the TS cohort alone revealed the presence of a second metabolic pattern that correlated with OCD in these patients. This OCD-related pattern (OCDRP) was characterized by reduced activity of the anterior cingulate and dorsolateral prefrontal cortical regions associated with relative increases in primary motor cortex and precuneus. Subject expression of OCDRP correlated with the severity of this symptom (r = 0.79, p < 0.005).

CONCLUSION

These findings suggest that the different clinical manifestations of TS are associated with the expression of 2 distinct abnormal metabolic brain networks. These, and potentially other disease-related spatial covariance patterns, may prove useful as biomarkers for assessing responses to new therapies for TS and related comorbidities.

Characterization of wax as a potential diffraction intensity standard for macromolecular crystallography beamlines

A number of commercially available waxes in the form of thin disc samples have been investigated as possible diffraction intensity standards for macromolecular crystallography synchrotron beamlines. Synchrotron X-ray powder diffraction measurements show that beeswax offers the best performance of these waxes owing to its polycrystallinity. Crystallographic lattice parameters and diffraction intensities were examined between 281 and 309 K, and show stable and predictable thermal behaviour. Using an X-ray beam of known incident flux at lambda = 1 A, the diffraction power of two strong Bragg reflections for beeswax were quantified as a function of sample thickness and normalized to 10(10) photons s(-1). To demonstrate its feasibility as a diffraction intensity standard, test measurements were then performed on a new third-generation macromolecular crystallography synchrotron beamline.

Intra-articular magnesium sulfate (MgSO4) reduces experimental osteoarthritis and nociception: association with attenuation of N-methyl-D-aspartate (NMDA) receptor subunit 1 phosphorylation and apoptosis in rat chondrocytes

OBJECTIVE

To study the effects of intra-articular injection of magnesium sulfate (MgSO(4)) on the development of osteoarthritis (OA) and to examine concomitant changes in the nociceptive behavior of rats.

METHODS

OA was induced in Wistar rats with intra-articular injection of collagenase (500 U) in the right knee; the left knee was left untreated. In the OA+MgSO(4) group (n=7), the treated knee was injected with 500-microg (0.1-ml) MgSO(4) twice a week for 5 consecutive weeks starting at 1 week after collagenase injection; in the OA group (n=7), the same knee was injected with the same amount of physiological normal saline. In the MgSO(4) group (n=6), naïve rats received only MgSO(4) injections; in the control group (n=6), naïve rats received only physiological normal saline injections. Nociceptive behavior (mechanical allodynia and thermal hyperalgesia) on OA development was measured before and at 1, 2, 4, 6, and 8 weeks after collagenase injection, following which the animals were sacrificed. Gross morphology and histopathology were examined in the femoral condyles, tibial plateau, and synovia. Immunohistochemical analysis was performed to examine the effect of MgSO(4) on N-methyl-D-aspartate (NMDA) receptor subunit 1 phosphorylation (p-NR1) and apoptosis in the articular cartilage chondrocytes.

RESULTS

OA rats receiving intra-articular MgSO(4) injections showed a significantly lower degree of cartilage degeneration than the rats receiving saline injections. MgSO(4) treatment also suppressed synovitis. Mechanical allodynia and thermal hyperalgesia showed significant improvement in the OA+MgSO(4) group as compared to the OA group. Moreover, MgSO(4) attenuated p-NR1 and chondrocyte apoptosis in OA-affected cartilage.

CONCLUSIONS

Our results indicate that local intra-articular administration of MgSO(4) following collagenase injection in an experimental rat OA model (1) modulates chondrocyte metabolism through inhibition of cell NMDA receptor phosphorylation and apoptosis, (2) attenuates the development of OA, and (3) concomitantly reduces nociception.

Beamline I11 at Diamond: a new instrument for high resolution powder diffraction

The performance characteristics of a new synchrotron x-ray powder diffraction beamline (I11) at the Diamond Light Source are presented. Using an in-vacuum undulator for photon production and deploying simple x-ray optics centered around a double-crystal monochromator and a pair of harmonic rejection mirrors, a high brightness and low bandpass x-ray beam is delivered at the sample. To provide fast data collection, 45 Si(111) analyzing crystals and detectors are installed onto a large and high precision diffractometer. High resolution powder diffraction data from standard reference materials of Si, alpha-quartz, and LaB6 are used to characterize instrumental performance.

Considerable Enhancement of Field Emission of SnO(2) Nanowires by Post-Annealing Process in Oxygen at High Temperature

The field emission properties of SnO(2) nanowires fabricated by chemical vapor deposition with metallic catalyst-assistance were investigated. For the as-fabricated SnO(2) nanowires, the turn-on and threshold field were 4.03 and 5.4 V/mum, respectively. Considerable enhancement of field emission of SnO(2) nanowires was obtained by a post-annealing process in oxygen at high temperature. When the SnO(2) nanowires were post-annealed at 1,000 degrees C in oxygen, the turn-on and threshold field were decreased to 3.77 and 4.4 V/mum, respectively, and the current density was increased to 6.58 from 0.3 mA/cm(2) at the same applied electric field of 5.0 V/mum.

The ikaite-to-vaterite transformation: new evidence from diffraction and imaging

Vaterite is one of three polymorphs of calcium carbonate (CaCO3) found in nature, the others being calcite and aragonite. Here the formation of vaterite from decomposition of ikaite (CaCO3·6H2O) was investigated using synchrotron powder diffraction and scanning electron microscopy. The crystallite sizes of vaterite (∼40 nm) were found to be much smaller than those of the precursor ikaite (∼0.5–1.0 µm) as a result of vaterite nucleating as ikaite dehydrates. The rate of decomposition to vaterite increases with temperature, indicating kinetic control of this transformation. It is postulated that the structural arrangement of the hydration sphere around Ca2+in ikaite determines the orientation of Ca2+and CO32−ions such that vaterite nucleates upon dehydration. This implies that the dehydration of a precursor hydrated phase such as ikaite is required for vaterite nucleation.

Anin situmethod for the study of strain broadening using synchrotron X-ray diffraction

A tensonometer for stretching metal foils has been constructed for the study of strain broadening in X-ray diffraction line profiles. This device, which is designed for use on powder diffractometers and was tested on Station 2.3 at Daresbury Laboratory, allowsin situmeasurements to be performed on samples under stress. It can be used for data collection in either transmission or reflection modes using either symmetric or asymmetric diffraction geometries. As a test case, measurements were carried out on an 18 µm-thick copper foil experiencing strain levels of up to 5% using both symmetric reflection and symmetric transmission diffraction. All the diffraction profiles displayed peak broadening and asymmetry which increased with strain. The measured profiles were analysed by the fundamental-parameters approach using theTOPASpeak-fitting software. All the observed broadened profiles were modelled by convoluting a refineable diffraction profile, representing the dislocation and crystallite size broadening, with a fixed instrumental profile predetermined using high-quality LaB6reference powder. The deconvolution process yielded `pure' sample integral breadths and asymmetry results which displayed a strong dependence on applied strain and increased almost linearly with applied strain. Assuming crystallite size broadening in combination with dislocation broadening arising from f.c.c.a/2〈110〉{111} dislocations, the variation of mechanical property with strain has been extracted. The observation of both peak asymmetry and broadening has been interpreted as a manifestation of a cellular structure with cell walls and cell interiors possessing high and low dislocation densities.

Longitudinal analysis of inpatient care utilization among people with intellectual disabilities: 1999-2002

BACKGROUND

There has been no longitudinal study in Taiwan to identify the nature and the scale of medical care utilization of people with intellectual disabilities (IDs) up to the present. The aim of this study is to describe inpatient utilization among people under ID care in institutions in order to identify the pattern of medical care needs and the factors affecting utilization in Taiwan.

METHOD

The subject cohort was 168 individuals with ID who were cared for by a large public disability institution from 1999 to 2002 in Taipei, Taiwan.

RESULTS

On the examination of the inpatient care that these persons underwent, it was found that these individuals had a heightened need (inpatient rate: 10.1-14.9%) for inpatient care compared with the general population with disabilities (9.37%) in Taiwan. The main reasons for hospitalization were pneumonia, gastrointestinal disorders, cellulites, orthopaedic problems, epilepsy and bronchitis. Using the full model of Generalized Estimating Equations for inpatient care utilization, the factors including low income family, living in an institution, being a subject with cerebral palsy and being a high outpatient user all influenced the use of inpatient care.

CONCLUSIONS

This study highlights that health authorities need to promote health planning more in order to ensure an excellent quality of health monitoring and health promotion among people with ID cared for by institutions.

Excellent Field-Emission Properties of P-Doped GaN Nanowires

GaN nanowires with P doping were synthesized via a simple thermal evaporation process. The P-doped GaN nanowires have average diameters of approximately 100 nm and lengths up to tens of micrometers. Scanning electron microscope and high-resolution field-emission transmission electron microscope analyses revealed that P doping results in a rough surface morphology of GaN nanowires. Field-emission measurements showed that P doping effectively decreases the turn-on field of GaN nanowire to 5.1 V/mum, holding promise of application as an electron emitter. The rough surface is responsible for enhancement of the field-emission properties of GaN nanowires.

From Al4B2O9 Nanowires to BN-Coated Al18B4O33 Nanowires

A novel route was proposed to completely coat aluminum borate nanowires by in situ providing the precursor for BN coating. Uniformly BN-coated Al18B4O33 nanowires could be obtained by the reaction of Al4B2O9 nanowires with ammonia at high temperature. The high-temperature unstable Al4B2O9 nanowires were converted into Al18B4O33 nanowires, simultaneously evaporated boron oxide. The reaction between the in situ generated vapors and ammonia ensures that the BN layers are attached tightly on the surface of the as-formed Al18B4O33 nanowires.

Production and characterization of single-crystal FeCo nanowires inside carbon nanotubes

We describe the synthesis of novel monocrystalline FeCo nanowires encapsulated inside multiwalled carbon nanotubes (MWNTs). These FeCo nanowires exhibit homogeneous Fe and Co concentrations and do not contain an external oxide layer due to the presence of insulating nanotube layers. The method involves the aerosol thermolysis of toluene-ferrocene-cobaltocene solutions in inert atmospheres. The materials have been carefully characterized using state-of-the-art high-resolution transmission electron microscopy (HRTEM), electron-energy-loss spectroscopy (EELS), scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDX), electron diffraction, HREELS-STM elemental mapping, X-ray powder diffraction, and SQUID magnetometry. We noted that the formation of FeCo alloys occurs at relatively low pyrolytic temperatures (e.g., 650-750 degrees C). These single-crystal nanowires, which have not been reported hitherto, always exhibit the FeCo (110) plane parallel to the carbon nanotube axis. The FeCo nanomaterials have shown large coercive fields at room temperature (e.g., 900 Oe). We envisage that these aligned ferromagnetic nanowires could be used in the fabrication of high-density magnetic storage devices and magnetic composites.

The new materials processing beamline at the SRS Daresbury, MPW6.2

A new beamline (MPW6.2) has been designed and built for the study of materials during processing where three synchrotron techniques, SAXS, WAXS and XAS, are available simultaneously. It has been demonstrated that Rietveld refinable data can be collected from silicon SRM 640b over a 60 degrees range in a time scale of 1 s. The data have been refined to a chi(2) of 2.4, the peaks fitting best to a Pearson VII function or with fundamental parameters. The peak halfwidths have been found to be approximately constant at 0.06 degrees over a 120 degrees angular range indicating that the instrumental resolution function has matched its design specification. A quantitative comparison of data sets collected on the same isotactic polypropylene system on MPW6.2 and DUBBLE at the ESRF shows a 17% improvement in angular resolution and a 1.8 improvement in peak-to-background ratio with the RAPID2 system; the ESRF data vary more smoothly across detector channels. The time-dependent wide-angle XRD was tested by comparing a hydration reaction of gypsum-bassanite-anhydrite with energy-dispersive data collected on the same system on the same time scale. Three sample data sets from the reaction were selected for analysis and gave an average chi(2) of 3.8. The Rietveld-refined lattice parameters are a good match with published values and the corresponding errors show a mean value of 3.3 x 10(-4). The data have also been analysed by the Pawley decomposition phase-modelling technique demonstrating the ability of the station to quickly and accurately identify new phases. The combined SAXS/WAXS capability of the station was tested with the crystallization and spinodal decomposition of a very dilute polymer system. Our measurements show that the crystallization of a high-density co-polymer (E76B38) as low as 0.5% by weight can be observed in solution in hexane. The WAXS and SAXS data sets were collected on the same time scale. The SAXS detector was calibrated using a collagen sample that gave 30 orders of diffraction in 1 s of data collection. The combined XRD and XAS measurement capability of the station was tested by observing the collapse and re-crystallization of zinc-exchanged zeolite A (zeolite Zn/Na-A). Previous studies of this material on station 9.3 at the SRS were compared with those from the new station. A time improvement of 38 was observed with better quality counting statistics. The improved angular resolution from the WAXS detector enabled new peaks to be identified.

Value of bronchoalveolar lavage combined with transbronchial lung biopsy in the diagnosis of peripheral lung cancer

BACKGROUND

Bronchoalveolar lavage (BAL) is a safe and established procedure to evaluate interstitial lung diseases and pulmonary tuberculosis. The diagnostic rate of peripheral lung cancer invisible through bronchoscopy applied by transbronchial lung biopsy (TBLB) is still low. The study was designed to evaluate whether BAL combined with TBLB might improve the positive value in the diagnosis of peripheral lung cancer.

METHODS

Thirty-seven of 72 patients who presented with peripheral lung lesions in chest radiography were proven to have a malignancy according to the final reports of cytology, histology, and clinical evidence. Each patient received BAL with or without TBLB. The patterns of chest radiography of the malignancies included 33 of infiltrative type and 4 of massive or nodular type.

RESULTS

BAL alone revealed positive malignant cells in 18 of 37 cases (sensitivity 48.6%), and the diagnostic value significantly increased to 73.0% (p < 0.05) with BAL + TBLB. In the infiltrative type of lung cancer, the diagnostic rate of BAL + TBLB (78.8%) was significantly improved compared to that of BAL alone (51.5%, p < 0.05). There was no difference of diagnostic value in those with nodular type. BAL + TBLB can achieve a very high diagnostic rate (100%) in cases of metastatic malignancy (n = 4). Only 2 patients developed bleeding post BAL + TBLB, and it was easily controlled by epinephrine spraying. One patient developed self-limited hemoptysis.

CONCLUSION

BAL + TBLB is a safe and valuable procedure to achieve a high sensitivity rate in the diagnosis of peripheral lung cancer, especially of the infiltrative type.

The value of transbronchial lung biopsy in the diagnosis of peripheral lung tumors according to cell type

BACKGROUND

Transbronchial lung biopsy (TBLB) is a useful diagnostic tool for peripheral lung tumors. However, the success rate is variable. Our study was designed to investigate the value of TBLB without fluoroscopic guidance in the diagnosis of variable cell types of peripheral lung cancers.

METHODS

A retrospective study was conducted to investigate a total of 597 patients who had undergone fiberoptic bronchoscopy for lung mass on chest X-ray in Chang Gung Memorial Hospital from January 1996 to December 1998. The lung masses were proven to be malignant by cytology and histology.

RESULTS

Of 358 patients (60.0%) proven with malignancy, 107 patients presented with peripheral lung cancer (17.9%), including 59 with adenocarcinoma, 26 with squamous cell carcinoma, 11 with poorly differentiated carcinoma, 3 with small cell carcinoma, and 8 with metastatic cancers. The diagnostic rate of peripheral lung cancer by TBLB reached 54.2%. The sensitivity rates of detection of non-small cell type by TBLB were adenocarcinoma, 50.9%; squamous cell carcinoma, 61.5%; and poorly differentiated carcinoma, 72.7%, while that of small cell carcinoma was 100%. In contrast, the sensitivity rate of TBLB for metastatic cancers was lower (12.5%) than for primary lung cancers. Repeated TBLB of peripheral lung cancers increased the diagnostic rate from 49.5% to 54.2%.

CONCLUSION

TBLB is an effective bronchoscopic sampling technique in the diagnosis of peripheral lung tumors without additional risk. The use of TBLB in the clinical routine should be encouraged.

Angular resolution of parallel foils on a synchrotron powder diffractometer

In an attempt to improve the resolution in flat-plate diffraction geometry, a new set of parallel foils, 100 microm spacing, 365 mm long with an aperture of 20 x 20 mm(2), has been commissioned. The study was carried out using the two-circle diffractometer of station 2.3 at the SRS. In order to properly quantify the improvements, a detailed and comparative study of the instrumental resolution using the new and existing foils, of 200 micron spacing, is reported. A number of cubic materials, BaF2, Si and CeO2, that are known to show well defined Bragg peaks over the full 2theta angular range available, were investigated.

Station 16.3: a high-resolution single-crystal diffraction facility at the SRS, Daresbury

SRS station 16.3 is now a fully scheduled user facility for high-resolution and high-energy single-crystal X-ray diffraction. It is based on a large three-axis diffractometer, designed and constructed at Daresbury for a wide range of physics and materials science applications. Served by wiggler 16 (a 6 T superconducting wavelength-shifter), the station has access to a broad spectrum of photon energies, extending to over 50 keV, and is designed for simple polarization-state tuning by motorized height adjustment of all optical components. This paper outlines the key design features and some of the science projects carried out during the first year of operation.

New high- and low-temperature apparatus for synchrotron polycrystalline X-ray diffraction

A high-temperature furnace with an induction heater coil and a cryogenic system based on closed-cycle refrigeration have been assembled to enhance the non-ambient powder diffraction facilities at the Synchrotron Radiation Source, Daresbury Laboratory. The commissioning of the high- and low-temperature devices on the high-resolution powder diffractometer of Station 2.3 is described. The combined temperature range provided by the furnace/cryostat is 10-1500 K. Results from Fe and NH(4)Br powder samples are presented to demonstrate the operation of the apparatus. The developments presented in this paper are applicable to a wide range of other experiments and diffraction geometries.

High-Pressure Cell for the Study of In-Situ Hydrates Using Energy-Dispersive X-ray Diffraction

A high-pressure low-temperature cell has been developed for in-situ diffraction studies of carbon dioxide and propane gas hydrate crystallization. The design and implementation of the cell, which can operate up to 3.5 MPa and down to 253 K, are described. Using synchrotron energy-dispersive X-ray diffraction, the first growth of the hydrate crystals from solution has been successfully observed. The lattice parameters of the hydrate crystals were found to be 11.927 (2) and 17.196 (2) A, respectively.

A Novel X-ray Diffractometer to Study the Texture of Materials

An X-ray energy-dispersive diffraction technique to study the texture of materials using synchrotron radiation has been developed. The design and commissioning of the diffraction instrument are described. The technique was first applied to study a drawn-wire aluminum sample which has a well known deformation texture. To demonstrate its capability further, results obtained from an erbium evaporated thin film are also presented.

Cyclical strain increases endothelin-1 secretion and gene expression in human endothelial cells

We examined the effects of cyclical strain on endothelin-1 (Et-1) secretion and Et-1 mRNA levels in human umbilical vein endothelial cells. Cultured endothelial cells grown on a flexible membrane base were deformed by vacuum to 20% of maximum strain, at 60 cycles/min, for various time periods. The rate of Et-1 release from strain- treated cells and their Et-1 mRNA levels were measured. Cells subjected to strain increased their Et-1 secretion into the culture medium from 0.17 ng/hr/10(6) cells to 0.44 ng/hr/10(6) cells. Concomitantly, the Et-1 mRNA levels in strained cells increased 1.4-, 2.1- or 2.6- fold (vs control unstrained cells) after 0.25, 0.5 or 6 hours of strain, respectively. Cells exposed to longer periods of strain (> 6 hrs) did not further increase their mRNA expression. Pretreatment with calphostin C, a specific inhibitor of protein kinase C, before straining completely abolished Et-1 mRNA expression. These results indicate that mechanical strain can modulate the secretion of Et-1 from endothelial cells by increasing Et-1 mRNA levels via the protein kinase C pathway. Elevation of Et-1 secretion and gene expression in endothelial cells under physiological strain might influence normal or pathological states of the vasculature and cardiac growth.

The effects of selenium on gestation, fertility, and offspring in mice

Supplementation of mice from 22 d old with the K-Selenocarrageenan (0.25 ppm Se) in drinking water reduced gestation period by 3.2 d. Selenium supplementation increased litter size by 53.8% and average litter weight by 5%. Continuous supplementation with selenium (0.25 ppm) of mice until the age of 50-56 d significantly increased the concentration of selenium and the glutathione peroxidase activity in whole blood and liver. In serum, fluorescent peroxidized lipid products were decreased by 22% and reducing sugar was decreased by 16% compared to unsupplemented controls. In whole blood of young mice, collagen was increased by 14%. IR differential spectra of whole blood show strong absorption at the acrylamide band, suggesting a role of selenium in preventing lipid peroxidation, as well as a stabilizing effect on blood proteins.