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Gold nanoparticles of 10-24 and 5-8 nm in size were obtained by chemical citrate reduction and UV photoreduction, respectively, on acid-treated multiwalled carbon nanotubes (MWCNTs) and on ZnO/MWCNT composites. The shape and size of the deposited Au nanoparticles were found to be dependent upon the synthetic method used. Single-crystalline, hexagonal gold particles were produced in the case of UV photoreduction on ZnO/MWCNT, whereas spherical Au particles were deposited on MWCNT when the chemical citrate reduction method was used. In the UV photoreduction route, n-doped ZnO serves as the e(-) donor, whereas the solvent is the hole trap. All materials were fully characterised by UV/Vis spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy and BET surface analysis. The catalytic activity of the composites was studied for the selective hydrogenation of alpha,beta-unsaturated carbonyl compound 3,7-dimethyl-2,6-octadienal (citral). The Au/ZnO/MWCNT composite favours the formation of unsaturated alcohols (selectivity=50% at a citral conversion of 20%) due to the presence of single-crystalline, hexagonal gold particles, whereas saturated aldehyde formation is favoured in the case of the Au/MWCNT nanocomposite that contains spherical gold particles.

An understanding of the cross-neutralisation of snake venoms by antibodies is important for snake antivenom development. We investigated the cross-neutralisation of brown snake (Pseudonaja textilis) venom, taipan (Oxyuranus scutellatus) venom and death adder (Acanthophis antarcticus) with commercial antivenoms and monovalent anti-snake IgG, using enzyme immunoassays, in vitro clotting and neurotoxicity assays. Each commercial antivenom bound all three venoms, and neutralised clotting activity of brown snake and taipan venoms and neurotoxicity of death adder venom. The 'in-house' monovalent anti-snake venom IgG raised against procoagulant brown snake and taipan venoms, did not neutralise the neurotoxic effects of death adder venom. However, they did cross-neutralise the procoagulant effects of both procoagulant venoms. This supports the idea of developing antivenoms against groups of snake toxins rather than individual snake venoms.

In this study, we demonstrate that human neuroblastoma SH-SY5Y cells transfected with human tyrosine hydroxylase isoform 1 (SH + TH cells) were substantially more resistant to cell death induced by hydrogen peroxide and 6-hydroxydopamine when compared to wild-type SH-SY5Y cells (SH cells). SH + TH cells exhibit increased levels of dopamine (DA) compared to SH cells. Incubation with hydrogen peroxide or 6-hydroxydopamine (10-100microM) for 24 h caused a significant reduction in cell viability and increased apoptosis in both cell types. However, these effects were significantly reduced in the SH + TH cells when compared to the SH cells. The SH + TH cells showed an improved ability to detoxify peroxide, which correlated with an increase in glutathione peroxidase and glutathione reductase activities, while catalase activity was unchanged. Our data suggest that a preconditioning-like mechanism linked to higher DA levels increased the resistance of SH + TH cells against oxidative insults, which is at least in part related to an augmentation in the activity of glutathione-related antioxidant enzymes.

A novel approach towards fabricating free-standing and self-supporting highly aligned CNT arrays with integrated top and bottom contacts for the design and implementation of future CNT-based sensor devices is reported.

We consider the problem of finding the densest closed packing of hard disks with proposed different radii in a circular environment, such that the radius of the circumcircle is minimal. The subspace of the quasioptimum configurations of this problem exhibits the property of ultrametricity.

We consider the problem of finding the densest closed packing of hard disks with proposed different radii in a circular environment, such that the radius of the circumcircle is minimal. With our approach, we are able to find denser packings for various problem instances than known from the literature. Both for the dynamics of the simulation and for the optimum values of the radii of the circumcircles, we find various scaling laws.

Objective: Persistent neurocognitive deficits have been described in bipolar mood disorder. As far as we are aware, no study have examined whether the cognitive impairment is presented in the same way in a Brazilian sample., Method: Cognitive function of 66 patients with bipolar disorder (32 with depressive symptoms and 34 euthymic) and 28 healthy subjects was examined using a complete cognitive battery., Results: Patients with bipolar disorder presented a significantly poorer performance in eight of the 12 subtests when compared to healthy subjects. There was no significant difference between the subgroups of patients. These patients showed impairment in both verbal and non-verbal cognitive function., Conclusion: Cognitive impairment was found in both groups of patients with bipolar disorder. The findings described here suggest an overall impairment of cognitive function, independent of mood symptoms. This is in line with data showing that cognitive deficits may be a persistent characteristic of bipolar disorder.

Irukandji syndrome is usually characterized by delayed severe abdominal, back and chest pain associated with autonomic effects including diaphoresis, hypertension and, in severe cases, myocardial injury and pulmonary oedema. It is most often associated with envenoming by the jellyfish Carukia barnesi, but a number of other jellyfish, including Alatina mordens, are now known to produce Irukandji syndrome. In the present study, nematocyst-derived venom from A. nr mordens (150-250 microg/kg, i.v.) produced a long-lasting pressor effect in anaesthetised rats. This pressor response (250 microg/kg, i.v.) was significantly inhibited by prior administration of the alpha-adrenoceptor antagonist prazosin (200 microg/kg, i.v.) but not by CSL box jellyfish antivenom (300 U/kg, i.v.). A. nr mordens venom 250 microg/kg (i.v.) caused marked increases in plasma adrenaline and noradrenaline concentrations following administration in anaesthetised rats. The venom did not contain appreciable amounts of either adrenaline or noradrenaline. A. nr mordens venom (25 microg/ml) produced a contractile response in rat electrically stimulated vas deferens which was markedly reduced in tissues pre-treated with reserpine (0.1mM) or guanethidine (0.1mM). Sodium dodecyl sulphate (SDS)-PAGE analysis showed that A. nr mordens venom is comprised of multiple protein bands ranging from 10 to 200 kDa. Western blot analysis using CSL box jellyfish antivenom indicated several antigenic proteins in A. nr mordens venom, however, it did not detect all proteins present in the venom. This study characterizes the in vitro and in vivo effects of A. nr mordens venom and indicates that the cardiovascular effects are at least partially mediated by endogenous catecholamine release.

Recently it has been suggested that the Australian snake antivenoms made by CSL Ltd. are in fact not truly monovalent and may contain antibodies to other snake venoms because the horses are injected with multiple snake venoms. It is unclear to what extent various monovalent antivenoms can neutralise the effect of other venoms, whether this is due to a mixture of antibodies or true cross-reactivity, and whether this has any clinical significance. We aimed to study the immunological and functional properties of brown snake (Pseudonaja spp.) antivenom (BSAV) and tiger snake (Notechis spp.) antivenom (TSAV) against their respective venoms using enzyme immunoassays (EIA) and in vitro clotting studies. There was significant overlap between the two antivenoms with both TSAV and BSAV being detected by EIA on brown snake venom (BSV)-coated and tiger snake venom (TSV)-coated wells, respectively. In a competition EIA, increasing amounts of immunoaffinity-purified hen anti-brown antibodies (IgYp) mixed with TSAV reduced TSAV measured on TSV-coated wells. Both BSAV and TSAV prevented the clotting activity of both venoms. IgYp also prevented the clotting activity of TSV, suggesting true cross-reactivity. The cross-reactivity of TSAV and BSAV with BSV and TSV, respectively, was likely due to each being a mixture of anti-brown and anti-tiger antibodies, but there was partial cross-reactivity demonstrated by the effect of IgYp. Single-polyvalent antivenom for brown snake and tiger snake may be feasible in the future.

Incisional hernias occur in up to 11 per cent of patients undergoing abdominal surgery. Up to 50 per cent of these patients with hernias will require repeat operative procedures. Management of these hernias have focused primarily on tensile strength of the mesh material, have not addressed currently used materials, and have not compared the strength of these repairs with each other. Forty-nine adult Sprague-Dawley rats had an incisional hernia created by removing a portion of their abdominal wall that was then repaired primarily, using either a composite mesh, Dual mesh (Gore-Tex), or polypropylene mesh. Six weeks after the repair, the rats were euthanized. Hydrostatic distension of the abdominal cavity was performed to compare bursting strength of each repair. Wound tensile strength was assessed and compared. Tissue samples were also taken to compare repair types for incorporation of prosthetic materials. The gross weight of the animals subjected to hydrostatic distention was equivalent between groups, as was the volume required prior to failure of the repair. There was a trend toward improved tensile strength of the Prolene mesh repair, which had a lower average inflammatory and fibrosis score on histology. Overall, the type of mesh used for repair does not seem to impact significantly the strength of the repair when assessed 6 weeks postoperatively. Choice of prosthetic material to repair the hernia should be made based on economics and handling characteristics alone. Prolene mesh has satisfactory strength with the least amount of inflammation and fibrosis.

We recently introduced a realistic order book model [T. Preis, Europhys. Lett. 75, 510 (2006)] which is able to generate the stylized facts of financial markets. We analyze this model in detail, explain the consequences of the use of different groups of traders, and focus on the foundation of a nontrivial Hurst exponent based on the introduction of a market trend. Our order book model supports the theoretical argument that a nontrivial Hurst exponent implies not necessarily long-term correlations. A coupling of the order placement depth to the market trend can produce fat tails, which can be described by a truncated Lévy distribution.

We have developed a chemical vapor deposition (CVD) process for the catalytic growth of carbon nanotubes (CNTs), anchored in a comose-type structure on top of porous alumina substrates. The mass-flow conditions of precursor and carrier gases and temperature distributions in the CVD reactor were studied by transient computational fluid dynamic simulation. Molecular-beam quadrupole mass spectroscopy (MB-QMS) has been used to analyze the gas phase during ferrocene CVD under reaction conditions (1073 K) in the boundary layer near the substrate. Field-emission (FE) properties of the nonaligned CNTs were measured for various coverages and pore diameters of the alumina. Samples with more dense CNT populations provided emitter-number densities up to 48,000 cm(-2) at an electric field of 6 V microm(-1). Samples with fewer but well-anchored CNTs in 22-nm pores yielded the highest current densities. Up to 83 mA cm(-2) at 7 V microm(-1) in dc mode and more than 200 mA cm(-2) at 11 V microm(-1) in pulsed diode operation have been achieved from a cathode size of 24 mm2.

For this study, 66 patients with a preoperative diagnosis of unilateral primary inguinal hernia were randomized to undergo laparoscopic totally extra peritoneal (TEP), laparoscopic transabdominal (TAPP), or open inguinal hernia repair with polypropylene mesh (Lichtenstein type). Both the operative team caring for the patient postoperatively and the patient were blinded to the operative approach by placement of a large dressing covering the abdomen, which was not removed until postoperative day 3. The patients recorded their pain level on a visual analog pain scale daily. Medication usage also was recorded. All patients were seen at 7-day intervals until they returned to work. The patients were interviewed during their postoperative visits by an investigator blinded to the operative approach and questioned regarding their ability to return to work and their pain levels. The average number of lost work days in all the groups was 12, and there was no significant difference between the three groups (p = 0.074). The average operating time for the TAPP procedure was 59 min, less than the time required to complete either the TEP or the Lichtenstein approach, which had equivalent operative times (p = 0.027). The material cost was significantly lower for the Lichtenstein repair (1,200 dollars less) than for either of the laparoscopic approaches, a saving primarily related to consumable operating room supplies. The TEP repair costs were minimally higher than those for the TAPP repair (125 dollars more). No significant differences were noted in the postoperative pain scales, and the use of postoperative oral analgesics was equivalent. The higher operative costs noted for the laparoscopic hernia repairs were not offset by a shortened convalescence. Postoperative pain appears to be equivalent regardless of the operative approach chosen and is easily managed with oral analgesics.

Snake venom induced consumption coagulopathy (VICC) is a common complication of snake bite due to prothrombin activators or thrombin-like enzymes in the venom. This study aimed to determine the efficacy and dose of antivenom for treating VICC in patients envenomed by brown snakes (Pseudonaja spp.), including in vitro coagulation studies. In serial blood samples from patients with brown snake envenoming, venom and antivenom concentrations were measured using enzyme immunoassays. In vitro mixtures of brown snake venom and antivenom were used to investigate antivenom binding, neutralisation of prothrombin activity, prevention of venom-mediated clotting and effect on thrombin generation parameters using a thrombinoscope. In 27 envenomed patients the median venom concentration was 20 ng/mL (Interquartile range[IQR]:12-44 ng/mL) prior to antivenom and was not detected after antivenom administration, including 9 patients given one vial. In vitro, 200 microg/mL of antivenom bound all free venom at venom concentrations seen in patients. In vitro prothrombinase activity of the venom (using a chromogenic substrate) was not neutralised by antivenom. However, for venom concentrations seen in humans, 100 microg/mL of antivenom prevented venom clotting activity in human plasma and 479 microg/mL neutralised procoagulant venom activity measured by triggering thrombin generation. One vial of antivenom appears to be sufficient to bind and neutralise all venom in patients with severe brown snake envenoming.

Background: The reported advantages of the laparoscopic approach to appendectomy are shortened hospital stay, less postoperative pain, and earlier return to usual activities (work). However, a prospective, randomized, double-blind trial comparing laparoscopic appendectomy with open appendectomy in active-duty males failed to disclose a benefit of laparoscopic appendectomy with regards to postoperative pain and return to work. The aim of our study was to compare open and laparoscopic appendectomy in overweight patients., Methods: We conducted a prospective, randomized, double-blind study to determine whether laparoscopic appendectomy or the open procedure in overweight patients offers a significant reduction in lost workdays, postoperative pain, or operative time from. Open appendectomy in overweight patients (those with a body mass index > or =25) may be more difficult due to excessive subcutaneous adipose tissue. The open incision may be of considerable size, which may result in increased postoperative pain and a prolonged convalescence., Results: There was a statistically significant increase in operative time for laparoscopic appendectomy of 11 minutes. As expected, the aggregate incision length for open appendectomy was twice that of the laparoscopic appendectomy., Conclusion: The data from this prospective, randomized, double-blind study failed to demonstrate any significant reduction in lost workdays, postoperative pain, or operative time with laparoscopic appendectomy.

Although a commercial snake venom detection kit (SVDK) is available to distinguish between the five major snake groups in Australia, there is no assay for quantifying venom or antivenom concentrations in envenomed patients. Serum samples were obtained from patients with brown snake (Pseudonaja spp.) envenoming before and after the administration of antivenom and patients with suspected brown snake bites but no evidence of envenoming. Enzyme immunoassays (EIAs) were developed for free venom, free antivenom and the venom-antivenom complex. Standard samples measured in duplicate had a coefficient of variation of less than 10%. The EIA for venom was able to detect brown snake venom down to concentrations of 3 ng/mL. A high baseline absorbance was measured in some patients that did not change with the addition of excess antivenom to the samples. In these patients, the baseline absorbance was subtracted from all measurements to calculate the true venom concentration. The EIA for brown snake antivenom had a limit of detection of 20 microg/mL, but 50 microg/mL was used as a cut-off based on assays in patients who had not received antivenom. The EIA for venom-antivenom complexes was unable to detect these at the low venom concentrations that occurred in patients. Quantification of venom and antivenom will help to determine the dose of antivenom required to bind venom and to establish appropriate end points for antivenom treatment.

Previous studies have reported loss of clonazepam from solutions administered intravenously from plastic infusion bags and administration sets. In palliative care, clonazepam is sometimes administered through syringe drivers using polyvinyl chloride (PVC) infusion tubing. No data currently exist to show whether use of PVC tubing affects the amount of clonazepam actually received by the patient. This study compared the use of two different types of PVC tubing with a non-PVC tubing. Solutions containing clonazepam or clonazepam and morphine were prepared with either normal saline or water for injection as diluent. Concentrations of morphine and clonazepam were determined using high-performance liquid chromatography. Significant loss of clonazepam (up to 50%) was observed in all solutions infused through PVC tubing. Solutions infused through non-PVC tubing retained greater than 90% of the initial concentration of clonazepam. It is recommended that when administering clonazepam using a syringe driver, non-PVC tubing be used.

Primary Objective: To investigate the relationship between performance on the Useful Field of View Test (UFOV) and driving performance following traumatic brain injury (TBI)., Participants: Sixty people with TBI referred for driving evaluation., Measures: Useful Field of View Test, Global Rating Scale and Driver Assessment Scale., Results: Subject performance diminished as the complexity of the UFOV sub-tests increased. There was a significant relationship between UFOV performance, particularly on the second sub-test, and on-road driving performance. Subject age and Trail Making Test, Part B were also predictive of driving performance., Conclusions: The UFOV can be used as a screening measure to determine readiness to participate in an on-road driving assessment.

Patients evaluated in acute pain will often have narcotics withheld until after the patient has been evaluated by a surgeon and has given informed consent. Concern that the patient would have impaired judgment due to narcotic effects often prevents the administration of timely pain relief. The Hopkins Competency Assessment Tool (HCAT) is a validated instrument for both psychiatric and medical patients; it has not been validated to evaluate drug effects on judgment. Thirty consecutive patients agreed to participate in the trial over a 12-month period. The HCAT was administered prior to the planned major elective procedure and repeated on each postoperative day up to and including postoperative day 5. Narcotic use (as morphine equivalents), HCAT scores, demographic data, and surgical procedures were recorded. The average age of our patients was 53 years. Twenty-seven patients passed the initial HCAT, and one patient failed subsequent exams. No correlation was seen between HCAT score and narcotic dose. Narcotic administration sufficient for pain control does not impair the ability to provide informed consent. The only patient who failed the HCAT after an initial passing score was somnolent on the narcotic dose.

Reaction of [(eta(5)-Me4EtC5)Fe(II)Cl(tmeda)] (tmeda = N,N,N'N'-tetramethylethylenediamine) with a polyanion solution of decacyclene (1) results in the formation of the triple-deckers [{(eta(5)-Me4EtC5)Fe}2-mu2-(eta(6):eta(6)-decacyclene)] (3) and [{(eta(5)-Me4EtC5)Fe}4-mu4-(eta(6):eta(6):eta(6):eta(6)-decacyclene)] (4). Metal complexation in 3 and 4 occurs on opposite faces of the pi perimeter in an alternating mode. The decacyclene ring adopts a gently twisted molecular propeller geometry with twofold crystallographic symmetry (C2). Complex 4 crystallizes in the chiral space group C222(1); the investigated crystal only contains decacyclene rings with M chirality. The handedness can be assigned unambiguously to the presence of the iron atoms. Cyclovoltammetric studies revealed quasireversible behavior of the redox events and a strong interaction of the Fe atoms in 3 and 4, exemplified by potential differences deltaE of 660 and 770(780) mV between the first and the second individual oxidation processes. This corresponds to a high degree of metal-metal interaction for 3 and 4. The successful syntheses of 3 and 4 together with earlier results from our laboratory proves that all five- and six-membered pi subunit sets of 1 are prone to metal complexation. A clear site preference in 1 towards the complexation of [Cp(R)]iron, -cobalt, and -nickel fragments exists.

Antimicrobial peptides are small, cationic, amphiphilic peptides of 12-50 amino acids with microbicidal activity against both bacteria and fungi. The eukaryotic antimicrobial peptides may be divided into four distinct groups according to their structural features: cysteine-free alpha-helices, extended cysteine-free alpha-helices with a predominance of one or two amino acids, loop structures with one intramolecular disulfide bond, and beta-sheet structures which are stabilised by two or three intramolecular disulfide bonds. Mammalian defensins are part of the last-mentioned group. The mammalian defensins can be subdivided into three main classes according to their structural differences: the alpha-defensins, beta-defensins and the recently described theta-defensins. Mammalian alpha-defensins are predominantly found in neutrophils and in small intestinal Paneth cells, whereas mammalian beta-defensins have been isolated from both leukocytes and epithelial cells. Recently, two novel human beta-defensins, human beta-defensin-3 (HBD-3), and human beta-defensin-4 (HBD-4) have been discovered. Similar to HBD-1 and HBD-2, HBD-3 has microbicidal activity towards the Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli) and the yeasts Candida albicans and Malassezia furfur. In addition, HBD-3 kills Gram-positive bacteria such as Streptococcus pyogenes or Staphylococcus aureus, including multi-resistant S. aureus strains, and even vancomycin-resistant Enterococcus faecium. In contrast to HBD-1 and HBD-2, significant expression of HBD-3 has been demonstrated in non-epithelial tissues, such as leukocytes, heart and skeletal muscle. HBD-4 is expressed in certain epithelia and in neutrophils. Its bactericidal activity against P. aeruginosa is stronger than that of the other known beta-defensins. Here we present an overview of human antimicrobial peptides with some emphasis on their antifungal properties.

Background: Endometrial cancer is the fourth most common malignancy among women. Metastases typically involve the lungs, peritoneal surfaces of the abdominal cavity, and lymph nodes outside the pelvis., Case: We report an unusually difficult complication of metastatic endometrial cancer occurring in a 57 year-old woman with paraaortic nodal recurrence: refractory occult gastrointestinal bleeding. Repeated upper endoscopic evaluation revealed an extrinsic mass eroding into the third portion of the duodenum. Segmental duodenal resection was performed, and the GI tract was reconstructed with a side-to-side duodenojejunostomy. The postoperative course was uneventful, and the patient experienced durable relief from continued bleeding and impending obstruction., Conclusion: We review the role of palliative surgery for bleeding complications of advanced cancer and the alternatives for treating invasive extrinsic lesions of the duodenum.

Driving skills are socially important, easily disrupted by brain injury, and potentially risky and difficult to evaluate afterward. The Useful Field of View test has seen successful use with severe traumatic brain injury (TBI), but its use with mild TBI victims has not been examined. This study shows its ecological insensitivity among persons with mild TBI or no impairment and suggests its use be limited to more severely impaired persons.

Tetrodotoxin (TTX) poisoning is an infrequent but important problem in South-eastern Asia. Despite it being a considerable public health issue in some countries and its potential lethality there continues to be no readily available method for measuring TTX in urine or serum. Previously published methods have used immunoaffinity chromatography, or the conversion of TTX to its C9-base derivative for measurement by mass spectrometry. A simple and reproducible method was developed using solid phase extraction cartridges to clean up serum and urine samples from TTX-poisoned patients, and the subsequent analysis of the samples by high performance liquid chromatography with post-column derivatisation and fluorescence detection. Minimum quantifiable concentrations of TTX were 5 and 20 ng/ml for serum and urine, respectively. Precision and accuracy of the assay were 13 and 15%, respectively. The standard curves were linear in the range of 20-300 ng/ml for urine and 5-20 ng/ml for serum. TTX was quantified in six samples of urine and six samples of serum from seven patients who ingested common toadfish and had clinical effects consistent with TTX poisoning. TTX was detected in all urine samples but in only one serum sample. Using this method confirmation of TTX poisoning will be far simpler and readily available. A 24 h urine collection in the period immediately following poisoning is likely to be the most sensitive test for TTX poisoning. With appropriately collected and timed serum and urine specimens it will be possible to properly define the pharmacokinetics of TTX in humans.

The delivery of subcutaneous medication by continuous infusion is common in palliative medicine. Many centers combine multiple medications, but the analytical confirmation of the compatibility and stability of these combinations has rarely been performed. This study examined the compatibility and stability of midazolam and dexamethasone using high performance liquid chromatography. Nine different solutions were prepared in polypropylene syringes by combining these two drugs with 0.9% sodium chloride. When these two drugs were combined in a syringe, there was significant loss of midazolam over 48 hours, with only 60-80% of the initial concentration remaining in syringes stored at 35-39 degrees C. This study demonstrates that cloudiness of a solution is not the only predictor of drug loss and that drug loss may occur even in solutions that remain clear at time of preparation. The clinical implications of these results are that dexamethasone and midazolam should not be combined in syringe driver solutions.

A single-crystal neutron diffraction analysis of the cluster complex [H(4)Co(4)(C(5)Me(4)Et)(4)] was carried out on the new quasi-Laue diffractometer VIVALDI at the Institut Laue-Langevin. The structure consists of four face-bridging hydrides attached to a tetrahedral cobalt metal core. Average distances and angles in the core of the molecule are as follows: Co-Co = 2.571(8), Co-C = 2.158(6), Co-H = 1.749(7), H.H = 2.366(9) A; Co-H-Co = 94.6(3), H-Co-H = 85.1(3) degrees. The hydride ligands are located off the Co-Co-Co planes by an average distance of 0.923(8) A. It is suggested that the dimensions of the HCo(3) fragments found in this molecule provide reasonable estimates for analogous distances and angles associated with chemisorbed H atoms situated on the 3-fold hollows of a cobalt surface. Crystallographic details: space group P2(1)/a (monoclinic); a = 21.979(2), b = 10.924(1), c = 34.406(2) A; beta = 90.81(1) degrees; Z = 8. Final agreement factor: R(F) = 0.099 for 3779 reflections [I > 2sigma(I)] collected at 20 K.

The catalytic CVD synthesis, using propyne as carbon precursor and Fe(NO3)3 as catalyst precursor inside porous alumina, gives carbon nanotube (CNT) bags in a well-arranged two-dimensional order. The tubes have the morphology of bags or fibers, since they are completely filled with smaller helicoidal CNTs. This morphology has so far not been reported for CNTs. Owing to the dense filling of the outer mother CNTs with small helicoidal CNTs, the resulting CNT fibers appear to be stiff and show no sign of inflation, as sometimes observed with hollow CNTs. The fiber morphology was observed by raster electron microscopy (REM), transmission electron microscopy (TEM), and atomic force microscopy (AFM). The carbon material is graphitic as deduced from spectroscopic studies (X-ray diffraction, Raman and electron energy-loss spectroscopy (EELS)). From Mössbauer studies, the presence of two different oxidation states (Fe0 and FeIII) of the catalyst is proven. Geometric structuring of the template by two different methods has been studied. Inkjet catalyst printing shows that the tubes can be arranged in defined areas by a simple and easily applied technique. Laser-structuring creates grooves of nanotube fibers embedded in the alumina host. This allows the formation of defined architectures in the microm range. Results on hydrogen absorption and field emission properties of the CNT fibers are reported.

Iron and titanium oxide nanoparticles have been synthesized in parallel mesopores of alumina by a novel organometallic "chimie douce" approach that uses bis(toluene)iron(0) (1) and bis(toluene)titanium(0) (2) as precursors. These complexes are molecular sources of iron and titanium in a zerovalent atomic state. In the case of 1, core shell iron/iron oxide particles with a strong magnetic coupling between both components, as revealed by magnetic measurements, are formed. Mössbauer data reveal superparamagnetic particle behavior with a distinct particle size distribution that confirms the magnetic measurements. The dependence of the Mössbauer spectra on temperature and particle size is explained by the influence of superparamagnetic relaxation effects. The coexistence of a paramagnetic doublet and a magnetically split component in the spectra is further explained by a distribution in particle size. From Mössbauer parameters the oxide phase can be identified as low-crystallinity ferrihydrite oxide. In agreement with quantum size effects observed in UV-visible studies, TEM measurements determine the size of the particles in the range 5-8 nm. The particles are mainly arranged alongside the pore walls of the alumina template. TiO2 nanoparticles are formed by depositing 2 in mesoporous alumina template. This produces metallic Ti, which is subsequently oxidized to TiO2 (anatase) within the alumina pores. UV-visible studies show a strong quantum confinement effect for these particles. From UV-visible investigations the particle size is determined to be around 2 nm. XPS analysis of the iron- and titania- embedded nanoparticles reveal the presence of Fe2O3 and TiO2 according to experimental binding energies and the experimental line shapes. Ti4+ and Fe3+ are the only oxidation states of the particles which can be determined by this technique. Hydrogen reduction of the iron/iron-oxide nanoparticles at 500 degrees C under flowing H2/N2 produces a catalyst, which is active towards formation of carbon nanotubes by a CVD process. Depending on the reaction conditions, the formation of smaller carbon nanotubes inside the interior of larger carbon nanotubes within the alumina pores can be achieved. This behavior can be understood by means of selectively turning on and off the iron catalyst by adjusting the flow rate of the gaseous carbon precursor in the CVD process.

Reaction of the half-sandwich complexes [(eta5-Me4RC5)M(eta2:O-acac)] (M = Co, Ni; R = Me or Et) with di- and trianions of the polycondensed pi-hydrocarbon decacyclene results in formation of the first Co and Ni triple-decker complexes of this hydrocarbon. For the title compound NMR spectra as well as a crystal structure analysis reveal an antarafacial coordination of two (eta5-Me4EtC5)Co fragments at the central six-membered ring and one of the neighboring five-membered rings of decacyclene. The bridging pi-perimeter decacyclene displays a bowl-shaped topology. In the case of Ni, coordination of two (eta5-Me5C5)Ni fragments at the central six-membered ring of decacyclene is observed, based on the results of 1H and 13C NMR studies. This coordination mode is without precedent for nickel organometallic compounds reported so far. The cobalt complex shows a rich spectroelectrochemistry. Results of cyclic voltammetry and coupled ESR experiments reveal a strong interaction of both metal centers in the mixed-valent monocation of [(eta5-Me4EtC5)Co2(mu-eta5:eta4-C36H18)]. This categorizes the title compound into Robin Day class III.

Objective: To establish the validity of the Orientation Log (O-Log) by comparison with the Galveston Orientation and Amnesia Test (GOAT)., Design: Correlation of daily measures of orientation., Setting: Acute rehabilitation hospital., Subjects: Sixty-eight inpatients receiving rehabilitation following traumatic brain injury (TBI)., Primary Measures: The O-Log and GOAT., Results: There was a significant correlation between the GOAT and O-Log (r = .901, P<.001). A cutoff of 25 on the O-Log was found to be comparable with the 75 cutoff on the GOAT. The scales were equivalent in measuring duration of posttraumatic amnesia., Conclusions: The O-Log is a valid measure of orientation for people with TBI and offers some advantages in administration over the GOAT.

Bis(toluene)iron 9 reacts with Lappert's stannylene [Sn[CH(SiMe3)2]2] (4) to form the paramagnetic bis-stannylene complex [[(eta6-toluene)Fe-Sn-[CH(SiMe3)2]2]2] (10). Compound 10 reacts with H2O to form the hydroxo hydrido complex [(eta6-C7H8)(mu-OH)(H)-Fe-[Sn[CH(SiMe3)2]2]2] (12) in high yield; its solid-state structure has been elucidated by X-ray and neutron diffraction analysis. In agreement with the 1H NMR results, 12 contains a hydridic ligand whose exact coordination geometry could be determined by neutron diffraction. The 1H and 119Sn NMR analysis of 12 suggested a multicenter Sn/Sn/H/Fe bonding interaction in solution, based on significantly large values of J(Sn,H,Fe) = 640+/-30 Hz and J(119Sn,119Sn) = 4340+/-100 Hz. In solution, complex 12 exists as two diastereomers in a ratio of about 2:1. Neutron diffraction analysis has characterized 12 as a classical metal hydride complex with very little Sn...H interaction and a typical Fe-H single bond (1.575(8) A). This conclusion is based on the fact that the values of the Sn...H contact distances (2.482(9) and 2.499(9) A) are not consistent with strong Fe-H...Sn interactions. This finding is discussed in relation to other compounds containing M-H...Sn units with and without strong three-center interactions. The neutron diffraction analysis of 12 represents the first determination of a Sn-H atomic distance employing this analytical technique. The cobalt analogues [(eta5-Cp)(mu-OH)(H)Co-[Sn[CH(SiMe3)2]2]2] (15) and [(eta5-Cp)(OD)(D)Co-[Sn[CH-(SiMe3)2]2]2] [D2]15, which are isolobal with 12, were prepared by the reaction of [(eta5-Cp)Co-Sn[CH(SiMe3)2]2] (14) with H2O and D2O, respectively. The magnitude of J(Sn,H) (539 Hz) in 15 is in the same range as that found for 12. The molecular structure of 15 has been determined by X-ray diffraction which reveals it to be isostructural with 12. The coordination geometries of the Co(Fe)-Sn1-O-Sn2 arrangements in 12 and 15 are fully planar within experimental error. Compounds 10 and 15 are rare examples of fully characterized complexes obtained as primary products from water activation reactions.

The pi-(arene)bis(stannylene) complex bis(bis(2-tert-butyl-4,5,6-trimethylphenyl)SnFe(eta6-toluene) (Sn-Fe-Sn, 15) is accessible in high yields by a metal-atom-mediated synthesis between iron atoms, toluene, and the stannylene [bis(2-tert-butyl-4,5,6-trimethylphenyl)Sn](3). Complex 15 has a half-sandwich structure with short Fe -Sn bonds (2.432(1) A) and a trigonal-planar coordination at both the Fe and Sn atoms. The distance between the two Sn centers is 3.56 A. Complex 15 is stable under ambient conditions and displays a pi-arene lability, so far rarely observed for (arene)iron complexes; this leads to an irreversible substitution of the arene and formation of fivefold-coordinated zerovalent iron complexes. The pi-arene lability of the title compound is a result of the Fe-Sn bonding situation, which can be interpreted, on the basis of an extended Huckel molecular orbital calculation, as being solely a donation of the 5sigma lone-pair of Sn into empty or half-filled acceptor d orbitals on Fe. As the calculations reveal, there is little backbonding from the iron to the tin, and the strong sigma donation leads to an increased occupation of the pi-antibonding orbitals of the eta6-arene, which are mainly responsible for the experimentally observed arene lability. Fe and Sn Mossbauer spectra support the polar character of Sn(sigma+)-->Fe(sigma-) with strong sigma donation from tin to iron, but significantly low iron-to-tin pi backdonation.

The synthesis and structure of heterobimetallic Co/Sn complexes [(eta5-CpR)Co-Sn[CH(SiMe3)2]2] (CpR = C5Me5 2; C5EtMe4 3) are described. Insertion reactions of sulfur and selenium into the unbridged heteronuclear Co-Sn bonds of 1, 2, and 3 (R= H5 1, Me5 2, EtMe4 3) have been studied. Depending on the stoichiometry of the chalcogen element used, novel ternary Sn-chalcogen-Co clusters (8, 9, 15, and 16) can be synthesized, and their molecular structures, which represent rare examples of crystallographically characterized cases of ternary transition metal/chalcogen/tin complexes, have been determined. Electrochemistry shows that complexes 8 and 9 are able to support reversibly either the removal or addition of one electron. Insertion of a further (Cp)Co-E (E = chalcogen) fragment significantly affects the electron distribution and causes complexes 9 and 16 to undergo two consecutive one-electron oxidations. The EPR spectra of the respective monocations have been recorded. In all cases, the unpaired electron strongly interacts with the cobalt nucleus(i), thus testifying that the main contribution to the relevant HOMO orbitals comes from the cobalt atom(s).

Survivors of traumatic brain injury often have long-term sensory, cognitive and motor deficits that may impair vehicle operation. However, relatively little is known about the driving status and driving characteristics of brain injury survivors. To better understand driving following traumatic brain injury, a survey of driving status, driving exposure, advice received about driving and evaluations of driving competency was administered to a convenience sample of traumatic brain injury survivors (n = 83). The majority of survey participants had experienced either moderate or severe traumatic brain injuries based on the Glasgow Coma Scale. A total of 60% of the survey participants reported that they were currently active drivers. Most individuals (> 60%) who had returned to driving reported driving every day and more than 50 miles per week. Traumatic brain injury survivors frequently received advice about driving from family members, physicians or non-physician health care professionals, but over half (63%) had not been professionally evaluated for driving competency. The presence of high driving exposure, coupled with a lack of widespread driving fitness testing, suggests that some traumatic brain injury survivors have characteristics that may evaluate their risk for vehicle crashes. However, subsequent prospective studies that directly assess driver safety will be needed to confirm this possibility.

A method for analyzing flecainide in plasma was developed and assessed. Based on the use of C18 extraction columns eight or fewer times, the rapid and simple extraction procedure provided consistent, high-efficiency flecainide extraction (>85%). Using reverse-phase, high-performance liquid chromatography with fluorometric detection, flecainide acetate was detectable to approximately 15 ng/ml. Retention times of the internal standard and flecainide were 8.9 to 9.2 and 9.8 to 10.4 minutes, respectively, and short sample preparation and run times enabled results to be delivered within 2 to 3 hours of receiving samples. The assay was linear for the standard range 20 ng/ml to 2 microg/ml (r2 with three standards, >0.999) and delivered a high level of accuracy. Quality control concentrations obtained from eight assays consistently fell within 5% of nominal values (100 ng/ml and 1 microg/ml). Based on four assays, the assay was also reproducible with calculated-between and within-assay coefficients of variation of less than 1% and 3%, respectively. The authors found that the performance of this assay was excellent and that the solid-phase extraction technique was simple, rapid, and cost effective.

The administration of drugs by subcutaneous infusion is routinely practiced in palliative medicine for the management of patients who are no longer able to take oral medication. It is not uncommon for two or more drugs to be combined in subcutaneous infusion solutions. The combination of an opioid and a short-acting benzodiazepine is frequently required. Unfortunately, the stability of benzodiazepines and newer opioids, such as fentanyl, has not been determined. This study examined the stability of solutions containing either fentanyl alone or fentanyl and midazolam in combination. Eight different solutions were assessed for up to 7 days following preparation. The solutions were prepared in polypropylene syringes using 0.9% saline as a diluent. Duplicate syringes were stored at approximately 5 degrees C, 22 degrees C, and 38 degrees C. High performance liquid chromatography was the analytical technique used to measure fentanyl and midazolam. Initial concentrations ranges were 13.2-38.9 micrograms/mL for fentanyl and 282-959 micrograms/mL for midazolam. It was found that fentanyl (+/- midazolam) was very stable (> 95%) when stored at temperatures ranging from 5 degrees C to 38 degrees C for at least 1 week. Midazolam (+ fentanyl) was not as stable as fentanyl under the same storage conditions and underwent time-dependent decomposition of up to 12.1% (observed at 7 days when stored at 38 degrees C). When stored at 22 degrees C and 38 degrees C, more than 90% of initial midazolam concentrations were retained for 4 days following preparation and for 7 days when stored at 5 degrees C. The clinical implications of these results are that, on the basis of physicochemical stability, subcutaneous infusion solutions containing fentanyl and midazolam may be prepared at intervals of 4 days (or 7 days if stored under refrigerated conditions).

Objective: To determine if ultrasonography is useful in evaluating penetrating injuries of the trunk to assess whether violation of the peritoneum or pleura has occurred., Methods: The study group was 29 patients who suffered gunshot (n = 17), stab (n = 10), or shotgun (n = 2) wounds. The abdomen was at risk in 21 injuries, the thorax in eight. The results of physical examination and plain x-rays suggested the pleura and or peritoneum might be intact in all patients. Using a 7-MHz transducer, wound tract(s) were images, looking for the presence of soft-tissue air and/or echolucent areas consistent with soft-tissue blood. Injuries were deemed extraperitoneal or extrapleural if (1) the entire tract was visualized; (2) it appeared superficial to the deepest fascial structure in that area; and (3) in shotgun injuries, all visible pellets on x-ray films were identified by ultrasound in the abdominal wall., Results: Evidence of penetration occurred in four abdominal wounds and one thoracic wound. These were confirmed by operation in the abdominal cases and by subsequent chest x-ray examination in the one thoracic wound. The diagnosis of nonpenetration was confirmed in all the remainder by serial benign abdominal examination (n = 15), chest x-ray examination (n = 8), and laparoscopy (n = 1). Positive and negative predictive accuracy were thus 100% in this pilot series., Conclusions: Ultrasonographic exploration of penetrating truncal injuries is feasible and accurate. Ultrasonographic wound exploration may serve as a noninvasive and safe replacement for diagnostic laparoscopy, conventional local wound exploration, peritoneal lavage, and 6-hour chest x-rays (repeated chest x-rays taken 6 hours after initial chest x-ray examination). If used as part of the initial physical examination, cost-effectiveness can also be realized.

Minimally invasive techniques now play an important role in virtually every aspect of general surgery. While it is unlikely that celiotomy for malignant disease will fall into obscurity as rapidly as open cholecystectomy, greater use of videoscopic techniques in surgical oncology are inevitable and will undoubtably improve patient care. Techniques of isopneumic laparoscopy have already proven useful in trauma, cholecystectomy, bowel resection, herniorrhaphy, and a variety of other procedures. Further advances in this technique are dependent on the development of "user friendly" abdominal wall retraction systems.

A review of numerous studies of the protein binding of vancomycin suggests major discrepancies among their results. The reported percent protein binding of vancomycin varies from 0% to 98%. The influence of pH and concentration on the protein binding of vancomycin was investigated in this study. There was a significant difference (p < 0.001) in percent protein binding in vancomycin-spiked plasma samples across the pH range of 7.0-8.0. There was no significant difference (p > 0.05) in percent protein binding in vancomycin-spiked plasma samples across the concentration range of 2-80 mg/L. It is likely that some of the variation reported to date may be due to a lack of control of pH during the measurement of protein binding of vancomycin.

Sustained-release morphine (MST) given by the rectal route was compared with oral MST in an open randomised cross-over trial in ten patients with cancer who received stable doses of MST. No significant difference was found in the areas under the curve of the concentration-time profiles (AUC) following oral or rectal administration for parent morphine. The AUCs determined for morphine-6-glucuronide (M6G) and morphine-3-glucuronide (M3G) after oral administration were approximately twice those obtained following rectal administration. The maximal concentration achieved was lower and the time to maximal concentration was longer following rectal administration for morphine, M6G and M3G. The relative mean arrival times following rectal administration were significantly longer for morphine and M3G but not for M6G. These findings suggest slower absorption but less first-pass metabolism of MST after rectal administration. No significant difference was noted between the oral and the rectal route in measurements on visual-analogue scales for pain or side effects. We recommend the rectal route as being suitable for MST administration when the oral route is no longer available. In changing from oral to rectal administration, the same dose and dose interval may be used, but dose adjustment may be needed.

The records from 1948 through 1967 of 344 previously untreated patients with squamous cell carcinoma of the oral cavity, oropharynx, supraglottic larynx and hypopharynx who had clinically positive cervical lymph node metastases staged N1, N2A, or N2B, and whose initial neck treatment consisted of external radiation therapy alone were reviewed. After appropriate exclusions the study group consists of 183 patients. The dose to the lymph node(s) was calculated retrospectively. The control rates for N1 lymph nodes are 91.5 per cent (76/83) and for N2 lymph nodes 78.5 per cent (55/70) in the patients whose lymph node(s) were well included in the irradiated volume and received a known dose. A dose response analysis shows that doses in the range of 6,500 rads to a single lymph node, 3 cm. or less in diameter, produce 90 per cent control. When a nonfixed metastatic lymph node of 3 cm. or more in diameter of multiple lymph nodes are present or there is questionable coverage, external irradiation alone cannot be relied upon for control and a neck dissection should follow.