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Historians have wrongly ignored the period when Nnamdi Azikiwe served as governor-general of Nigeria, just after its independence (1960-63). Archival materials in Britain, the United States, and Azikiwe’s own papers in Nigeria reveal that he played a dynamic role in Nigeria’s new government, struggling against the constitutional limits of his chosen position, especially concerning Nigeria’s role in convening pan-African conferences that would lead to the creation of the Organization of African Unity in 1963. Despite being on the margins of official policymaking, Azikiwe used his reputation as Nigeria’s preeminent pan-Africanist since the 1930s to shape the role Nigeria would play in Africa’s new age of independence. La période durant laquelle Nnamdi Azikiwe était gouverneur général du Nigéria juste après son indépendance (1960-63) a été ignorée, à tort, par les historiens. En effet, des documents d’archives en Grande-Bretagne, aux États-Unis et les propres documents d’Azikiwe au Nigéria révèlent qu’il a joué un rôle dynamique dans le nouveau gouvernement du Nigéria. Effectivement, Azikiwe a lutté contre les limites constitutionnelles de sa position de gouverneur, en particulier en ce qui concernait le rôle du Nigéria dans la convocation de conférences panafricaines qui conduiraient à la création de l’Organisation de l’unité africaine en 1963. Bien qu‘étant en marge de l‘élaboration des politiques officielles, Azikiwe a utilisé sa réputation de panafricaniste par excellence du Nigéria depuis les années 1930 pour façonner le rôle que le Nigéria jouerait dans le nouvel âge de l’indépendance de l’Afrique.

This paper describes the synthesis of neutral nickel(II) catalysts for the polymerization of ethylene. A series of 2-(arylamino)-5-methylcyclopent-2-en-1-one (aryl = 2,6-diisopropylphenyl, 2,4,6-tr...

This article examines the efforts of two anticolonial politicians from the British Empire who used official visits to London and the rhetoric of the Atlantic Charter (14 August 1941) to advance their political careers and self-government for their territories: Burma's U Saw in 1941, and Nigeria's Nnamdi Azikiwe in 1943. Rather than a repetition of the 'Wilsonian moment', these campaigns show how anticolonial forces long active across the Empire took advantage of the opening offered by the Atlantic Charter to make claims on the British government in its wartime weakness. Both U Saw and Azikiwe had been involved in anticolonial politics long before the Charter, but its appearance provided an opportunity to advance their position vis-à-vis political competitors as well as to win concessions from the imperial state. Although the two leaders had different immediate objectives, they both used the prestige of official visits to London and the ambiguous universality of the Charter's language in pursuit of their aims. Their ability to do so attests to the power of anticolonial movements by the early 1940s, and points to alternative paths which the Empire might have followed.

Postoperative delayed gastric emptying (DGE) is a very common complication after a pancreaticoduodenectomy (PD). This along with other complications can lead to increased health-care costs. This study investigates the costs and length of stay (LOS) associated with these. A retrospective study of 131 patients undergoing PD between 2000 and 2016 at Loma Linda University Health was performed. Chi-squared test was used to determine statistically significant differences between patients with and without DGE (according to the definition of the International Study Group of Pancreatic Surgery). Multiple logistic and linear regression analyses were performed to obtain adjusted odds ratios for variables of interest in association with DGE and relationship to LOS. Of 150 patients undergoing PD, 131 patients with tumors were analyzed. The overall incidence of DGE was 56 per cent. No pre- or postoperative factors were associated with increased risk of DGE. The median LOS for patients with DGE was 15 days

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC), although considered an acceptable treatment option in the management of selected patients with colon and appendiceal peritoneal carcinomatosis (PC), concerns about morbidity have limited its acceptance. Our objective was to evaluate the short- and long-term outcomes of CRS/HIPEC for appendix and colon PC performed at our institution and to elucidate factors predictive of patient outcomes. All patients who underwent CRS/HIPEC for appendix or colon PC from 2011 to 2017 were identified from our institution's prospective database. Postoperative outcomes, overall survival, and recurrence-free survival were assessed. Of 125 patients who underwent CRS/HIPEC during the study period, 45 patients were eligible (appendix n = 26; colon n = 19). The median postoperative length of stay was nine days (5-28 days). Grade III/IV complications occurred in 4/45 (8.8%) patients. There were no postoperative mortalities. Median DFS and overall survival have not yet been reached, in both the colon and appendix groups. As of the study conclusion date, 37/45 (82.2%) patients were alive with or without disease. Lymph node status was predictive of recurrence in appendix PC. In our experience, CRS/HIPEC can be safely performed with acceptable short- and long-term outcomes. Lymph node status is an important predictor of recurrence.

This chapter introduces the Alpine School and its original purpose and goals before leading into the story of the historical development of the current School for Student Leadership (SSL). It outlines the extensive political background behind the creation of this unique Victorian school and the search for an appropriate principal. The development of the school from a single campus to the current three campuses is detailed, with photos of each included to illustrate the diverse environmental contexts that are represented. Also presented is an outline of some of the major differences in the curriculum and overall experience that students receive through a term spent at the SSL, compared to that offered via traditional mainstream education. The different learning opportunities resulting from a program that focuses on providing a rite of passage for adolescents and includes experiential learning, reflection and a Community Learning Project are discussed, illustrating the contemporary approach used at the school to meet the cognitive, physical, social and emotional needs of the attending Year 9 students.

To understand which organic molecules are capable of binding to gold nanoparticles and/or inducing nanoparticle aggregation, we investigate the interaction of gold nanoparticles with small molecules and amino acids at variable pH. Dynamic Light Scattering (DLS) and ultraviolet-visible (UV-vis) spectra were measured on mixtures of colloidal gold with small molecules to track the progression of the aggregation of gold nanoparticles. We introduce the 522 to 435 nm UV-vis absorbance ratio as a sensitive method for the detection of colloidal gold aggregation, whereby we delineate the ability of thiol, amine, and carboxylic acid functional groups to bind to the surfaces of gold nanoparticles and investigate how combinations of these functional groups affect colloidal stability. We present models for mechanisms of aggregation of colloidal gold, including surface charge reduction and bridging linkers. For all molecules whose addition leads to the aggregation of gold nanoparticles, the aggregation kinetics were accelerated at acidic pH values. Colloidal gold is maintained only in the presence of anionic carboxyl groups, which are neutralized by protonation at lower pH. The overall reduced charge on the stabilizing carboxyl groups accounts for the accelerated aggregation at lower pH values.

Purpose: To compare immediate outcomes for patients who receive and those who do not receive heparin during lower limb endovascular intervention. Methods: A retrospective case series of 330 procedures for lower limb peripheral arterial occlusive disease. Patient records were interrogated for bleeding or thrombotic/embolic complications during or immediately after endovascular intervention for peripheral arterial occlusive disease. Results: Of the 220 patients who received heparin, 21 (9.6%) suffered an access site bleed compared with 2 of the 110 patients (2%) who did not receive heparin (odds ratio [OR] = 5.7; 95% confidence interval [CI] = 1.3-25; P =.01). There were 6 embolic/thrombotic complications in the patients who received heparin (2.7%) compared with 4 in those that did not receive heparin (3.6%; P =.74). In 187 cases, a closure or compression device was used (StarClose, n = 109; Angio-Seal, n = 42; FemoStop, n = 35; ProGlide, n = 1), of which there were 3 access bleeding complications (2%). One hundred and forty-three cases did not have a closure or compression device associated with 17 (12%) access bleeding complications (OR = 0.25; 95% CI = 0.09-0.64; P =.004). Conclusions: In this study, heparin use and nonuse of a closure or compression device was associated with an increased risk of access site bleeding. Embolic/thrombotic complications were uncommon.

BACKGROUND: Many trials in acute postoperative pain use morphine consumption as an end point. Age has been shown to have a significant influence on morphine consumption but is rarely considered in end point analysis. METHODS: Simulation was used to investigate the effect of age on the power of various sample sizes to detect differences in morphine consumption in control and study groups. RESULTS: The sample sizes required for 80% power were approximately twice that predicted by a sample size program when comparing morphine consumption using a t test without adjustment for age. CONCLUSIONS: The model suggests that variations in age have a profound effect on sample size. Researchers may need to account for this to prevent both type 1 and type 2 error.

Intra-articular infusion of local anaesthetic after joint arthroplasty is attractive in that it is simple and will not cause motor block. However, the efficacy of the technique has yet to be established. We enrolled 66 patients scheduled for unilateral total knee arthroplasty under general anaesthesia and single-shot femoral and sciatic nerve blocks. All patients had an intra-articular Painbuster® device sited at the end of the procedure. Patients were then randomised to control or one of two treatment arms – low-dose and high-dose ropivacaine. In the control group the balloon was filled with saline, in the low-dose group with 0.2% ropivacaine and in the high-dose group 0.375% ropivacaine. The catheters were infused continuously for 48 hours and then removed. Patients were followed up daily for three days to determine pain scores, opioid consumption and subjective assessment of the analgesic efficacy of the catheter. Data were analysed for 30 controls and 31 in the treatment arms. Both groups were similar. There were no significant differences between the control and treatment groups at all time points after adjustment for age. Patients in the high-dose group had higher pain scores and higher opioid consumption than the control groups from 24 to 48 hours. There were two cases of infection, both in the treatment groups.No positive benefit of intra-articular infusion of local anaesthetic after total knee arthroplasty could be identified. On the contrary there may be negative effects in terms of expense, pain and possibly infection risks.

Background: There is a perception that oral oxycodone is becoming a popular choice for post-caesarean section analgesia. There are a lack of published data quantifying the use of oxycodone and other drugs for post-caesarean section analgesia in Australasian practice. Aim: To determine the use of oxycodone and other drugs for multimodal analgesia post-caesarean section and to evaluate the compatibility of these drugs with breastfeeding. Method: Fellows of the Australian and New Zealand College of Anaesthetists from 41 Australian and New Zealand obstetric units were invited to participate in an online survey on analgesic preference (drug, route of administration, dosing schedule) postcaesarean section and whether breastfeeding considerations influenced their choice of analgesics. Results: 25 participants (response rate 61%) completed the survey. All of the responding obstetric units used multimodal analgesic protocols, which included oral and rectal paracetamol and non-steroidal anti-inflammatory drugs. Survey responses indicated that 50% of women in metropolitan hospitals and 95% of women in rural and regional hospitals would receive oral or rectal oxycodone post-caesarean section. Approximately, 15% of women would be asked about their intention to breastfeed. 6% of anaesthetists would modify their choice of analgesic if the patient was breastfeeding. Conclusion: The obstetric units preferred oral and rectal analgesics over parenteral opioids and non-steroidal antiinflammatory drugs. There was a high use of oxycodone for post-caesarean section analgesia. The analgesics chosen were largely compatible with breastfeeding. J Pharm Pract Res 2009; 39: 104-8.

Tracheal intubation through the intubating laryngeal mask airway (ILMA) has been evaluated, in controlled settings, as an acceptable alternative to laryngoscopic intubation. Our observational study was designed to examine the success rate of tracheal intubation using the ILMA in the prehospital setting after mannequin-based training.We examined all oral tracheal intubations performed by the Tasmanian Ambulance Service (TAS) from April 2005 to April 2006. TAS paramedics are occasional intubators, as defined in the study by Reeves et al.,(8) on average performing two intubations per paramedic per year. Fifty-eight paramedics received training in tracheal intubation through the ILMA. The primary outcome measure was tracheal intubation success. Our hypothesis was that paramedics would be able to successfully perform out-of-hospital tracheal intubation using the ILMA with minimal training.During the study period, 106 patients had out-of-hospital tracheal intubation performed by ambulance paramedics. Comparisons were made between the intubations with the ILMA and by laryngoscopy. The overall intubation success rate was 91% with the laryngoscope and 92% with the ILMA. The success rate for the first attempt at intubation was higher with the ILMA (81%) than with direct laryngoscopy (57%) (RR (95% CI): 1.74 (95% CI: 1.18-2.59, p = 0.009), regardless of ultimate success. The success rate when intubating unconscious patients using the ILMA was significantly higher (88%) than intubation using the laryngoscope (63%). These intubations were achieved without the administration of any sedation or paralytic medication.Intubation via the ILMA was as successful as conventional laryngoscopic intubation, requiring fewer attempts, although this was not statistically significant.

Plasmonic assays are an important class of optical sensors that measure biomolecular interactions in real-time without the need for labeling agents, making them especially well-suited for clinical applications. Through the incorporation of nanoparticles and fiberoptics, these sensing systems have been successfully miniaturized and show great promise for in-situ probing and implantable devices, yet it remains challenging to derive meaningful, quantitative information from plasmonic responses. This is in part due to a lack of dedicated modeling tools, and therefore we introduce PAME, an open-source Python application for modeling plasmonic systems of bulk and nanoparticle-embedded metallic films. PAME combines aspects of thin-film solvers, nanomaterials and fiber-optics into an intuitive graphical interface. Some of PAME’s features include a simulation mode, a database of hundreds of materials, and an object-oriented framework for designing complex nanomaterials, such as a gold nanoparticles encased in a protein shell. An overview of PAME’s theory and design is presented, followed by example simulations of a fiberoptic refractometer, as well as protein binding to a multiplexed sensor composed of a mixed layer of gold and silver colloids. These results provide new insights into observed responses in reflectance biosensors.

Background Pre-medication with clonidine reduces the requirement for volatile agents during general anaesthesia. This may also be true for anaesthesia with propofol, but the amount of dose reduction has not been measured. Because clonidine also affects cardiac output and thus regional blood flow it could alter the pharmacokinetics of propofol. This randomized, double-blind placebo-controlled trial aimed to study the effect of clonidine pre-medication on dose requirement for propofol during lower extremity vascular surgery using the bispectral index (BIS) as a measure of anaesthetic depth. Methods After oral pre-medication with either clonidine 3 μg kg−1 or placebo, 39 subjects had lower limb vascular surgery using propofol infusion for anaesthesia. Anaesthetic depth was adjusted to a BIS of 45. Predicted plasma propofol concentrations were noted every 30 min from a target-controlled propofol infusion pump and arterial samples were taken at the same time for propofol measurements. Results Patients in both groups were anaesthetized to similar depths of anaesthesia as indicated by BIS readings (P=0.44). The groups had comparable mean (95% CI) arterial concentrations of propofol, 4.8 (3.5–6.1) μg ml−1 in the patients given clonidine, and 4.6 (3.4–5.7) μg ml−1 in the patients given placebo (P=0.81). However, the average plasma concentration predicted by the target-controlled infusion was less in the clonidine group [3.2 (2.9–3.5)] than in the group given placebo [3.6 (3.3–3.9)] μg ml−1 (P Conclusions Pre-medication with clonidine reduces the requirement for propofol, which is a pharmacokinetic effect and not a pharmacodynamic central sedative effect.

Results are presented from a single and dual lens endoscopic PIV imaging system with a view to application of PIV where optical access is restricted such as internal flows. The dual lens PIV images were processed using cross-correlation, a cubic mapping function and standard stereoscopic relationships. For the single lens system, the images were processed using cross-correlation and a quadratic distortion-mapping function. Results have shown the single lens system to have in-plane errors an order of magnitude greater than the stereoscopic dual lens endoscopic PIV system. These errors are generated by perspective effects. Use of the stereo arrangement is therefore recommended wherever quantitative 3D velocimetry data is acquired using an endoscopic system. To cite this article: M. Reeves, N.J. Lawson, C. R. Mecanique 332 (2004).

This observational study assessed the potential role of the intubating laryngeal mask airway (ILMA™ ) for use by emergency care givers with limited laryngoscopy skills. Six ambulance officers with advanced airway training, five doctors with intubation experience and five doctors without intubation experience were given a short instruction course on the use of the ILMA. They subsequently used the device on 80 consenting subjects anaesthetized for elective surgery after the application of cricoid pressure and manual in-line stabilization of the cervical spine. All patients were successfully ventilated via the ILMA. Mean (SD) times in seconds to ventilation were 27 (10), 33 (18) and 47 (22) respectively in the occasional intubator ambulance officers, occasional intubator doctor and naï ve intubator groups. The numbers (percentage) failures to intubate via the ILMA in each group were 2 (7%), 5 (20%) and 4 (16%) respectively. Mean (SD) times in seconds to intubation were 32 (23), 32 (17) and 36 (25). There was no evidence of “learning” with repeated use. The feedback forms were strongly supportive of a prehospital trial and also of having an ILMA available during all intubations. Participants almost universally rated the ILMA as easy to use. This study supports further evaluation of the ILMA in a large pre-hospital trial.

Laser forming is, potentially, an attractive flexible manufacturing technique for the controlled forming of aerospace alloys. Laser forming experiments using a continuous-wave CO2 laser were performed on coupons of material 80 mm × 80mm in area and 2mm thick, with sequential passes of the laser beam, at a surface scanning rate of 20 mm/s with 90 s of convective cooling between passes. A novel surface profilometer that was specifically developed to operate under the conditions of high vibration and stray light typically found in laser machining applications recorded transient surface shape changes during individual laser passes at frame rates of 4 and 0.2 Hz. A finite element model was developed using ABAQUS for the laser forming of linear bends in free Ti-6A1-4V sheets, with sequentially coupled thermal and elastic-plastic analysis incorporating temperature-dependent material properties. Transient heat source scanning was implemented to simulate the experiment. Good agreement was found between the experimental three-dimensional shape data and those predicted by the transient model. In particular, the formation of an unwanted ‘camber’ distortion perpendicular to the desired main bend was correctly predicted; its magnitude and temporal evolution throughout the three laser passes, and during the periods of convective cooling, agreed well with the experimental data. The model and the shape measurement technique will enable the future predictive controlled laser forming of more complex three-dimensional shapes.

A persistent challenge in materials science is the characterization of a large ensemble of heterogeneous nanostructures in a set of images. This often leads to practices such as manual particle counting, and sampling bias of a favorable region of the “best” image. Herein, we present the open-source software, imaging criteria and workflow necessary to fully characterize an ensemble of SEM nanoparticle images. Such characterization is critical to nanoparticle biosensors, whose performance and characteristics are determined by the distribution of the underlying nanoparticle film. We utilize novel artificial SEM images to objectively compare commonly-found image processing methods through each stage of the workflow: acquistion, preprocessing, segmentation, labeling and object classification. Using the semi- supervised machine learning application, Ilastik, we demonstrate the decomposition of a nanoparticle image into particle subtypes relevant to our application: singles, dimers, flat aggregates and piles. We outline a workflow for characterizing and classifying nanoscale features on low-magnification images with thousands of nanoparticles. This work is accompanied by a repository of supplementary materials, including videos, a bank of real and artificial SEM images, and ten IPython Notebook tutorials to reproduce and extend the presented results.

One of the important problems of high-temperature superconductivity is to understand and ultimately to control fluxoid motion. We present the results of a new technique for measuring the pressure dependence of the transition to superconductivity in a diamond anvil cell. By measuring the third harmonic of the ac susceptibility, we determine the onset of irreversible flux motion. This enables us to study the effects of pressure on flux motion. The application of pressure changes interplanar spacing, and hence the interplanar coupling, without significantly disturbing the intraplanar superconductivity. Thus we are able to separate the effects of coupling from other properties that might affect the flux motion. Our results directly show the relationship between lattice spacing, effective-mass anisotropy, and the irreversibility line in Bi/sub 2/Sr/sub 2/CaCu/sub 2/O/sub 8+/spl delta//. Our results also demonstrate that an application of 2.5 GPa pressure causes a four-fold decrease in the effective-mass anisotropy.

Bahia grass (Paspalum notatum), johnson grass (Sorghum halpense) and switchgrass (Panicum virginatum) werecompared for their ability to accumulate 137Csand 90Sr from three different contaminated soilsin the presence and absence of either sphagnum peator poultry litter amendments. Above-ground plantbiomass did not differ between plants that were notexposed to these radionuclides and those that wereexposed to soil containing 137Cs or 90Sr.After three harvests, bahia, johnson and switchgrassplants accumulated from 17.2 to 67.3% of the137Cs and from 25.1 to 61.7% of the 90Sradded to the soil. Poultry litter and peat mossamendments increased aboveground plant biomass,activity of 137Cs or 90Sr in plant tissue, %accumulation of 137Cs or 90Sr from soil andthe plant bioconcentration ratio at each harvestcompared to the control (no amendment) treatment. Thegreatest increases in plant biomass, and radionuclideaccumulation were observed with poultry litter foreach of the three grass species. Johnson grass hadgreater aboveground plant biomass, activity of137Cs and 90Sr in plant tissue, %accumulation of 137Cs or 90Sr from soil andbioconcentration ratio in each soil amendment, at eachharvest compared to bahia and switchgrass. Thegreatest accumulation of 137Cs and 90Sr wasmeasured in johnson grass grown in soil that wasamended with poultry litter. These results suggestthat plant species selection and agronomic practicesmay need to be considered to maximize phytoremediationof radionuclide contaminated soils.

A rare case of isolated innominate artery arising from a left persistent arterial duct with a right aortic arch is presented. Of interest in this case is the retrograde flow in the left carotid system, the history of developmental delay, and the magnetic resonance image (MRI) brain findings suggestive of asymmetric volume loss affecting the left cerebral hemisphere. The authors postulate a possible mechanism of subclavian steal.

One of the important problems of high-temperature superconductivity is to understand and ultimately to control fluxoid motion. Here we present data on the pressure dependence of the irreversibility line measured up to 2.5 GPa. We observe that the application of pressure changes the interplanar coupling by decreasing the c-axis length, without significantly disturbing the intraplanar superconductivity. Our results directly show the relationship between lattice spacing and the irreversibility line in Bi(2)Sr(2)CaCu(2)O(8+delta), and demonstrate the potential for a dramatic reduction in the flux motion.

The annual number of published clinical trials in acute postoperative pain in adults has changed little in 15 yr and, as a fraction of all clinical trials published in the six highest impact journals in anesthesiology, has actually decreased from 16% (95% confidence interval: 12-20) to 11% (95% confidence interval: 9-15). However, the methodological quality of reports has improved, with explicit statements on power analysis, allocation concealment, and specification of primary end points exceeding 90% of reports in 2007. There has been a shift in hypothesis interests away from neuraxial analgesia and toward multimodal analgesia.

Many organic molecules, particularly biologicals, contain functional groups (ligands) that actively interact with metal ions in solution by adsorption, ion exchange, or chelation/coordination/complexation. Water-soluble organics have limitations as reagents for metal-ion separations from aqueous solutions. However, if the ligand molecule(s) are grafted on to an insoluble matrix, the resulting ligand(s)-containing product becomes useful for separations applications related to metal recovery or remediation. It was discovered that biomolecules containing a primary amino group, secondary amino group, or hydroxyl group could be grafted into a polyurethane polymeric network via in situ polymerization reactions. With carboxyl groups, grafted material showed good selectivity among a group of divalent metal cations, and a uranium-binding capacity of more than 10 mg/g of polymer. The material can be regenerated by sodium bicarbonate or sodium carbonate solution and reused. Data from a stirred-tank reactor showed fast uranium-binding kinetics, and breakthrough-elution studies with a packed-column reactor indicated promising process behavior.

We describe an electronic speckle pattern interferometer (ESPI) system that has enabled non-harmonic vibrations to be measured with μs temporal resolution. The short exposure period and high framing rate of a high-speed camera at up to 40,500 frames per second allow low-power CW laser illumination and fibre-optic beam delivery to be used, rather than the high peak power pulsed lasers normally used in ESPI for transient measurement. The technique has been demonstrated in the laboratory and tested in preliminary industrial trials. The ability to measure vibration with high spatial and temporal resolution, which is not provided by techniques such as scanning laser vibrometry, has many applications in manufacturing design, and in an illustrative application described here revealed previously unmeasured “rocking” vibrations of a car door. It has been possible to make the measurement on the door as part of a complete vehicle standing on its own tyres, wheels and suspension, and where the excitation was generated by the running of the vehicle's own engine.

The use of plants to accumulate low level radioactive waste from soil, followed by incineration of plant material to concentrate radionuclides may prove to be a viable and economical method of remediating contaminated areas. We tested the influence of arbuscular mycorrhizae on 137Cs and 90Sr uptake by bahia grass (Paspalum notatum), johnson grass (Sorghum halpense) and switchgrass (Panicum virginatum) for the effectiveness on three different contaminated soil types. Exposure to 137Cs or 90Sr over the course of the experiment did not affect above ground biomass of the three grasses. The above ground biomass of bahia, johnson and switchgrass plants accumulated from 26.3 to 71.7% of the total amount of the 137Cs and from 23.8 to 88.7% of the total amount of the 90Sr added to the soil after three harvests. In each of the three grass species tested, plants inoculated with Glomus mosseae or Glomus intraradices had greater aboveground plant biomass, higher concentrations of 137Cs or 90Sr in plant tissue, % accumulation of 137Cs or 90Sr from soil and plant bioconcentration ratios at each harvest than those that did not receive mycorrhizal inoculation. Johnson grass had greater aboveground plant biomass, greater accumulation of 137Cs or 90Sr from soil and plant higher bioconcentration ratios with arbuscular mycorrhizal fungi than bahia grass and switchgrass. The greatest accumulation of 137Cs and 90Sr was observed in johnson grass inoculated with G. mosseae. Grasses can grow in wide geographical ranges that include a broad variety of edaphic conditions. The highly efficient removal of these radionuclides by these grass species after inoculation with arbuscular mycorrhizae supports the concept that remediation of radionuclide contaminated soils using mycorrhizal plants may present a viable strategy to remediate and reclaim sites contaminated with radionuclides. ©

Abosede George's new book brings the history of childhood into colonial Lagos and explores childhood through a gendered lens, looking particularly at girlhood. George examines how both African and ...

A technique of measuring Tc(P) in the diamond anvil cell by the third harmonic of the ac susceptibility (V3f) is described. It requires no background subtraction and allows the use of gasket materials made from hardened steels. In addition, the observed peak structure in the V3f vs T data allows regions with different critical temperatures to be distinguished. Results for single crystals (with typical size, 0.25 mm×0.25 mm×0.1 mm) of the Tl2Ba2CuO6+δ and YBa2Cu3O7−δ systems are presented. The effects of sample inhomogeneities and nonhydrostatic conditions are discussed.

Structural inhomogeneities in thin single-crystal films of YBa 2 Cu 3 O 7− δ are characterized using high resolution X-ray diffraction. Results of these measurements show a distribution in the c -axis lattice parameter and variations in the integrated intensities of (00l) diffraction peaks. Both effects can be interpreted as due to a variance in the oxygen content. Films prepared under identical growth conditions, when subjected to different post-annealing treatments showed varying structural and superconducting properties. A film with 7− δ close to 7.0 had a transition temperature (T c ) of 91 K, a width ( Δ T c ) of 0.6 K, and a critical current density (J c ) of 6.5×10 6 A/cm 2 , whereas a film in which the oxygen content varied between 6.86 and 6.96 had a T c of 87 K, a Δ T c of 0.5 K, and a J c of 8.17×10 6 A/cm 2 . For each of the samples measured, the full width at half maximum (FWHM) of the (006) diffraction peak ranged between 340 and 2100 arc-seconds and was dependent on the method of preparation and the substrate. The J c s of these films were not sensitive to the quality of the film, as determined from the FWHM of the (006) peak, and the oxygen content, as determined from the (005) to (006) integrated intensity ratio. High resolution X-ray topographs showed uniform microstructure of the films, indicating that oxygen distribution is finely dispersed in the film.

High resolution x-ray diffraction measurements of YBCO single crystals with optimal transport properties reveal gross structural inhomogeneities, such as domains of different oxygen content and high dislocation densities. Thin epitaxial YBCO films show similar structural inhomogeneities.

Pseudomonas aeruginosa CSU, a nongenetically engineered bacterial strain previously shown to bind dissolved hexavalent uranium (as UO22+ and/or its cationic hydroxy complexes), shows promise as the basis of an immobilized-cell process for removal of dissolved uranium from contaminated wastewaters. A number of polymeric materials, including calcium alginate, polyacrylamide, polysulfone, and polyurethane, were evaluated as possible immobilization matrices for lyophilized biomass of P. aeruginosa CSU. Polyurethane-based materials such as hydrogel were identified as superior candidates for biomass immobilization. A novel polyurethane gel-bead fabrication technique was developed and successfully demonstrated at pilot-plant scale for producing mass quantities of spherical, uniform-size beads. The immobilized bacterial biomass was evaluated via the measurement of sorption isotherms and dynamics within a batch, stirred-tank reactor; and loading and elution behavior within a continuous, upflow, packed-bed columnar reactor. Sorption equilibrium and dynamics in a batch stirred tank were modeled with a pore-diffusion mass transfer model, by which a pore-diffusion coefficient was determined to be approximately 2.0 × 10−6 cm2/s for uranyl ion transport through the polyurethane gel matrix. The biosorbent beads were regenerable with dilute (0.01–0.1 M) sodium carbonate solutions. Preliminary column breakthrough-elution studies indicated that P. aeruginosa CSU biomass immobilized within polyurethane gel beads was effective for removal of uranium from low-concentration, acidic wastewaters.

A fiber optic nanobiosensor, with sensitivity comparable to commercial plasmonic sensors, a highly reduced sensing area, and the possibility of in-situ use is presented.

Chemical analysis of metabolites directly from cell samples at sub-cellular level in ambient conditions is essential to understand the biochemical pathways in these organisms. In order to achieve this goal we combine near-field ablation with mass spectrometry. As a first step towards the integration of near-field ablation with mass spectrometry, we will report preliminary results of the chemical analysis of Arabidopsis Thaliana.

As the initial experiments towards integrating the near-field ablation and a fiber-optic biosensor, we report the near-field ablation on Arabidopsis thaliana leaf samples with a 2μm ablation spot. We also report time-dependent spectral plots of detecting biomolecules in the ground Arabidopsis leaf solution. The sensitivity of detecting biomolecules with amino functional groups was improved by using a biosensor coated with a specific type of cross linkers.

This case study describes the Military Health System's (MHS) patient-centered medical home (PCMH) initiative and how it is being delivered across the MHS by the Army, Navy, and Air Force. The MHS, an integrated delivery model that includes both military treatment facilities and civilian providers and health care institutions, is transforming its primary care platforms from the traditional acute, episodic system to the PCMH model of care to maximize patient experience, satisfaction, health care quality, and readiness and to control cost growth. Preliminary performance measures are analyzed to assess the impact of PCMH implementation on the core primary care processes of the MHS. This study also discusses lessons learned and recommendations for improving health care performance through the PCMH care model.

Pseudomonas aeruginosa strain CSU, a nongenetically engineered bacterial strain known to bind dissolved hexavalent uranium (as UO{sub 2}{sup 2+} and/or its cationic hydroxo complexes) was characterized with respect to its sorptive activity. The uranium biosorption equilibrium could be described by the Langmuir isotherm. The rate of uranium adsorption increased following permeabilization of the outer and/or cytoplasmic membrane by organic solvents such as acetone. P. aeruginosa CSU biomass was significantly more sorptive toward uranium than certain novel, patented biosorbents derived from algal or fungal biomass sources. P. aeruginosa CSU biomass was also competitive with commercial cation-exchange resins, particularly in the presence of dissolved transition metals. Uranium binding by P. aeruginosa CSU was clearly pH dependent. Uranium loading capacity increased with increasing pH under acidic conditions, presumably as a function of uranium speciation and due to the H{sup +} competition at some binding sites. Nevertheless, preliminary evidence suggests that this microorganism is also capable of binding anionic hexavalent uranium complexes. Ferric iron was a strong inhibitor of uranium binding to P. aeruginosa CSU biomass, and the presence of uranium also decreased the Fe{sup 3+} loading when the biomass was not saturated with Fe{sup 3+}. Thus, a two-state process in which iron andmore » uranium are removed in consecutive steps was proposed for efficient use of the biomass as a biosorbent in uranium removal from mine wastewater, especially acidic leachates.« less

In laboratory experiments, unagitated soil slurry bioreactors inoculated with micro-organisms extracted from polychlorinated biphenyl-contaminated (PCBs) sediments from the Hudson River were used to anaerobically dechlorinate PCBs. The onset of dechlorination activity was accelerated by the addition of certain organic acids (pyruvate and maleate) and single congeners (2,3,6-trichlorobiphenyl). Dechlorination was observed under several working conditions after 19 weeks of incubation with PCB-contaminated soil and nutrient solution. Best results showed a drop in average chlorine content from 4.3 to 3.6 chlorines per biphenyl due to a loss of m-chlorines. Soil used for these experiments was obtained from a PCB-contaminated (weathered Aroclor 1248) site at an electric power substation. Dechlorination was observed with no sediment particles or other matrix being added.

The energy spectrum of the cuprates depends on the level of doping. Deviations from stoichiometry may introduce magnetic impurities, which, in turn, lead to a gapless scenario with peculiar optical, transport, magnetic, and thermodynamic properties.

The energy gap structure of the cuprates depends strongly on levels of doping. The stoichiometric compoundYBa2Cu3O7 displays a peculiar two-gap structure. Oxygen depletion is accompanied by the transition to the gapless state, and this is manifested in various transport, electromagnetic, etc. properties of the material. The temperature dependence of the penetration depth correlates with oxygen content and is characterized by various power laws in an oxygen depleted sample. In other cuprates, overdoping leads to gaplessness and a peculiar dependence of Hc2.

Thin barium titanate films, 0.5–8 μm thick, are obtained from a single-crystal bulk sample using ion slicing. The process, based on ion implantation and anodic bonding, separates thin films having areas of ∼1×1 cm2, from bulk crystals. The quality of the film is characterized by measurement of surface roughness and dielectric properties. The film permittivity retains its single-crystal value.

In this rapid communication, we present the surface vertical deposition (SVD) method to synthesize the gold nanoparticle films. Under conditions where the surface of the gold nanoparticle suspension descends slowly by evaporation, the gold nanoparticles in the solid–liquid–gas junction of the suspension aggregate together on the substrate by the force of solid and liquid interface. When the surface properties of the substrate and colloidal nanoparticle suspension define for the SVD, the density of gold nanoparticles in the thin film made by SVD only depends on the descending velocity of the suspension surface and on the concentration of the gold nanoparticle suspension.

A fabrication method for high-throughput, fiber-based tips for near-field scanning microscopy (NSOM) in the mid-infrared (λ ∼ 3 μm) has been developed. Several fiber materials have been investigated and recipes for wet-chemical etching have been varied to produce tips that are physically robust and are capable of low-loss transmission of high-power pulses of mid-infrared light. Ultimately, wet-chemical etching techniques are used on glass fibers to produce tips capable of focusing mid-infrared light to ablate material from sub-micron-sized regions of organic films. The power throughput of the tips is significantly increased by using a novel material, previously unreported for NSOM applications: germanate fibers. The tips produced are mechanically strong and capable of transmitting high light fluence without sustaining physical damage. Here, the development of these tips and their performance are described.

As a first step towards the chemical analysis of biological samples with sub-micron resolution, we report our experiments on the sub-cellular ablation of biological samples in their native environment. This has the potential to combine the near-field IR ablation with mass spectrometry, thus facilitating the study of the spatial distribution of proteins in cellular samples, at sub-cellular length scales. We report the ablation of hard and soft materials: cellular acetate cover slips in water and myoblast cell samples in growth media, with spot sizes as small as 1.5um under 3um wavelength radiation. The ablation threshold and fluence in these processes have been measured. We found that there is a dramatic increase in the ablation threshold fluences when we go from far-field to the near-field region. We will also report on the difference in the ablation mechanism in air and water medium. This approach has the potential to identify the protein expressed in cells in a relatively non-destructive manner.