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Posterior cortical atrophy (PCA) is a relatively rare neurodegenerative syndrome marked by prominent disturbance in visuoperceptual and visuospatial functioning. Its prevalence and incidence rates are unknown (Crutch SJ, Lehmann M, Schott JM, Rabinovici GD, Rossor MN, Fox NC, Lancet Neurol. 11:170-178, 2012). There has been increased awareness of this condition among the general public, with the diagnosis made by British author Sir Terry Pratchett (1948–2015). He was quite open about his journey with the disease, making several documentaries and appearing on a number of radio programs. He was initially misdiagnosed, which is typical with the challenges of making this diagnosis. This condition was also written about by American neurologist/author Dr. Oliver Sacks in his 2010 book, The Mind’s Eye, in which he describes this condition in one of his case reports.

PurposeThe purpose of this paper is to examine the use of bid information, including both price and non‐price factors in predicting the bidder's performance.Design/methodology/approachThe practice of the industry was first reviewed. Data on bid evaluation and performance records of the successful bids were then obtained from the Hong Kong Housing Department, the largest housing provider in Hong Kong. This was followed by the development of a radial basis function (RBF) neural network based performance prediction model.FindingsIt is found that public clients are more conscientious and include non‐price factors in their bid evaluation equations. With the input variables used the information is available at the time of the bid and the output variable is the project performance score recorded during work in progress achieved by the successful bidder. It was found that past project performance score is the most sensitive input variable in predicting future performance.Research limitations/implicationsThe paper shows the inadequacy of using price alone for bid award criterion. The need for a systemic performance evaluation is also highlighted, as this information is highly instrumental for subsequent bid evaluations. The caveat for this study is that the prediction model was developed based on data obtained from one single source.Originality/valueThe value of the paper is in the use of an RBF neural network as the prediction tool because it can model non‐linear function. This capability avoids tedious “trial and error” in deciding the number of hidden layers to be used in the network model.

A light and portable organic vapours monitor has been developed using piezoelectric (P/Z) quartz crystal to determine Volatile Organic Compounds (VOCs) commonly found in workplace air. Out of the eight coating material studied, High Vacuum Grease (HVG) was found to be the best for determining commonly encountered organic vapours such as 1,1,1-Trichloroethane, Chloroform, Benzene and Toluene in room air. The optimised coating weight was 23 μg HVG at a flow rate of 200 mL/min. Moisture was found to interfere and the use of a Nafion gas dryer was found to reduce the relative humidity to a constant 37 % for room air with 43–81 % relative humidity. Under optimised conditions, a mean sensitivity of 1.9 × 1−2 Hz/ppm was obtained for total VOCs with 17.2% RSD variation towards different VOCs. Excellent linear working ranges were obtained from 40 to 2400 ppm (v/v), with response time and recovery time within one minute up to 500 ppm (v/v) of analyte. High and relatively constant response factors were obta...

Solving the problem due to transition metals' comigration during electrokinetic injection, the transient isotachophoresis (ITP) procedure was developed to preconcentrate and focus transition metals during electrokinetic injection. It was found to provide a suitable method for trace metals' preconcentration from rainwater at sub-μg/L level from buffer system consisting of 30 mM hydroxylamine hydrochloride, 0.1 mM 1,10-phenanthroline, 1% methanol, 15 mM ammonium chloride, and 0.08 M urea at pH=3.7. Trace metals as Cd2+, Zn2+, Cu2+, Co2+, and Fe2+ (total Fe determined as Fe2+) are determined with working range from 0.5–80 μg/L, repeatability less than 7%, and detection limits from 0.1 to 0.5 μg/L under optimized operation conditions as follows: Injection at 3 kV for 40 s prior to CE run at +15 kV in buffer system developed and with 0.4 mM tetrabutyl ammonium bromide added to rain sample as terminating ion. Leading and terminating ion effect, buffer additive, and operation conditions on performance of ITP procedure were investigated. Procedure developed was applied for trace metals' determination in rain water collected in Hong Kong. It provides fast, efficient, and economic method determining transition metals in rain sample down to sub-μg/L level, reducing sample pretreatment time and eliminating off-column preconcentration steps often leading to contamination problems for transition metals determination at μg/L level. © 2000 John Wiley & Sons, Inc. J Micro Sep 12: 337–344, 2000

The applicability of the room temperature molten salt medium based on the 1-methyl-3-ethylimidazolium chloride/AlCl3 (MeEtImCl/AlCl3) system for the deposition of superconductor alloy precursors (Bi–Sr–Ca–Cu) was investigated. Problems of poor solubility of the constituent metal salts in the neutral melt and aluminium codeposition in the acidic melt were identified for the use of the chloroaluminate room temperature molten salt. Thus, a novel all-chloride molten system (MeEtImCl) was developed in the present work and used at 120°C. Cyclic voltammetry was used to investigate the suitability of Pt, Al, Ti, Cu and Ag as substrate for alloy deposition and aluminium was found to be the best for depositing alkaline earth metal alloys. The working deposition conditions were a constant potential of –1.72V for 75s in an electrolytic bath containing BiCl3 (0.068mol), SrCl2 (0.50mol), CaCl2 (0.18mol) and CuCl2 (0.050mol) in 1kg MeEtImCl (6.83mol). The compositions of the electrodeposits obtained were in close agreement with the mole ratios of the Bi–Sr–Ca–Cu superconductor alloy precursor.

Lithium chloride/ambient-temperature 1-methyl-3-ethylimidazolinium chloride-aluminium chloride ionic liquids are of interest for use in lithium batteries. The authors studied ion interactions in this system using FTIR and NMR spectroscopies. It is found that Li{sup +} strongly effects the AlCl{sub 4}{sup {minus}} ion. Effects of Li{sup +} concentration on the structure of the AlCl{sub 4}{sup {minus}} ion and the physical properties of the liquids are discussed.

A new electroanalytical method, DPSV, employing dual pulses (0.7V and −0.8V) prior to anodic scan (using staircase voltammetry) is developed for simultaneous determination of glucose and fructose. The electrochemistry of both sugars was studied prior to optimizing the operational parameters. The linear ranges were found to be 0.01–2.0 mM for both sugars, precisions (mean = 0.10 mM and n = 8) 1.8% and 2.4% and detection limits (estimated by 3 times the standard deviation) 0.001 and 0.003 mM for glucose and fructose, respectively. To establish the reliability of the method, various food additives were tested and found to give no interference effect under normal concentrations. HPLC method was carried out in parallel with the method for analyzing food, drink and honey samples. No statistically significant difference in the results was obtained for methods.

The applicability of the 1-methyl-3-ethylimidazolium chloride — AlCl3 system for lithium battery application was investigated. Lithium chloride was found to dissolve up to 1.59 mole ratio of LiAlCl4/MeEtImAlCl4 upon reaction between LiCl and AlCl3 in the melt. Density, conductivity and viscosity of the melt upon addition of LiAlCl4 were determined. The density was found to increase monotonically from 1280 to 1480 kg m−3, while the conductivity decreased rapidly from the initial value of 5.6 mS to a steady plateau at 3.4 mS. The viscosity was varied from 1.46 Ns m−2 to a small but distinct initial fall prior to rising to 2.75 Ns m−2 when the mole ratio of LiAlCl4 increased from zero to 1.59. The chronopotentiometric studies indicate a satisfactory electrochemical behaviour with no apparent attack of the melt by the formation of the reactive lithium alloys. 350 cycles were achieved with cycling efficiency over 90% using an optimal c.d. of 6 mA cm−2 for lithium deposition on aluminium substrate in the melt. Prolonged cycling improved the nucleation rate but led to an increase in the internal resistance and a gradual reduction in the charge and discharge capacity.

The immune response of CAF1 mice to various synthetic peptides (SP) related to the amino acid sequence (PDTRPAPGSTAPPAHGVTSA) of the tandem repeat of the MUC1 human breast mucin core peptide was evaluated. The most immunogenic preparations of the synthetic peptides were those conjugated to keyhole limpet hemocyanin (KLH) or clustered in a dendritic multiple antigenic peptide (MAP-4) configuration. The mice were immunized subcutaneously with synthetic peptides emulsified in RIBI adjuvant, employing various immunization protocols. Equivalently high IgG responses were induced using SP-KLH conjugates (GVTSAPDTRPAPGSTA-KLH) or an SP--MAP-4 chimeric configuration (SP1-6), which also included a universal malarial CST-3 T-helper epitope (SP1-6 = SAPDTRPAEKKIAKMEKASSVFNVVNS--MAP-4). These IgG antibodies bound both the appropriate MUC1 synthetic peptides and the cell surface expressed MUC1 mucin on murine mammary cells that had been transfected with the human MUC1 gene and a human breast cancer cell line that expresses cell-surface MUC1. A MAP-4 molecule, which included the entire 20-amino-acid sequence of the MUC1 tandem repeat (SP1-5 = PDTRPAPGSTAPPAHGVTSA-MAP-4) induced a poor IgG response. In contrast, all three types of molecule: SP-KLH, SP1-6 and SP1-5, were found to be good immunogens for the induction of specific delayed-type hypersensitivity (DTH) reactions measured using either synthetic peptides or MUC1-transfected cells. In addition, immunization with irradiated MUC1-transfected cells induced strong DTH reactions measured using synthetic peptides that expressed the PDTRP sequence, which has been shown to be, or to overlap, a T cell epitope in humans and a B cell epitope in mice. Finally, it was demonstrated that synthetic MUC1 peptide "vaccines" could be used both prophylactically and therapeutically to inhibit the growth of MUC1-transfected tumor cells and prolong the survival of tumor-bearing mice.

The recovery efficiencies of Cd, Cr, Cu, Fe, Ni, Pb and Zn during acid digestion by different acid mixtures and by block heater and microwave heating were determined for an estuarine sediment sample. For block heater heating, the aqua regia mixture was found the most powerful digestion agent, giving a high yield of 112% for Fe and a poorer yield of 83% for Pb. Compared to block heater heating, HNO3 digestion by a domestic microwave oven gave a lower yield for Cr, Cu, Fe and Ni. The digestion time of 3–6 min was possibly not sufficient to cause a complete release of the heavy metals. The recoveries for a heating time of 3.8 min and under ‘High Heat’ were determined as follows: Cd, 99%; Cr, 55%; Cu, 95%; Fe, 87%; Ni, 76%; Pb, 75%; Zn, 88%. Microwave digestion using HNO3 was used to determine the concentration of the above metals in two sediment cores from Hebe Haven and Ngau Mei Hoi, Hong Kong. Hebe Haven, which is close to a suburban area with some dyeing factories, has its surficial sediment enri...

Orlistat is a gastrointestinal lipase inhibitor approved for use in obesity. So far, no evidence has been reported on the use of orlistat in obese patients with coronary artery disease (CAD).To investigate the effect of orlistat on body weight and lipid profiles in obese patients with CAD and hypercholesterolemia.Thirty non-diabetic patients with CAD, body mass index (BMI)or = 25 kg/m(2) and low-density lipoprotein cholesterol (LDL-C)or = 2.6 and4.1 mmol/L were put on diet for 12 weeks. Those still having a BMIor = 25 kg/m(2) received orlistat 120 mg thrice daily for another 24 weeks.BMI was significantly reduced by 1.7% after 12 weeks of dietary treatment. The 24-week orlistat treatment resulted in further significant reduction in BMI (-2.8%) and LDL-C (-7.0%).Diet and orlistat treatment significantly reduced BMI and improved LDL-C in obese patients with CAD and hypercholesterolemia.

A new analytical procedure based on electrochromatography was developed for the separation and quantitation of 14 aldehydes and ketones (formaldehyde, acetaldehyde, acetone, acrolein, propionaldehyde, butanone, crotonaldehyde, isobutyraldehyde/butyraldehyde, 2-pentenaldehyde, isovaleraldehyde, valeraldehyde, benzaldehyde and hexanaldehyde) in ambient air currently to be regulated by the Hong Kong Environmental Protection Department. A volatile mobile phase using ammonium acetate compatible with mass spectrometry detection was developed and optimized as follows. Methanol: acetonitrile: aqueous buffer (4 mM ammonium acetate) = 65:5:30% v/v. With electrokinetic injection at 5 kV for 2 s, aqueous buffer pH adjusted to 8, applied voltage controlled at 25 kV, and detection at 360 nm in a fused-silica column packed with 3 microm ODS, a satisfactory separation was obtained for the 14 carbonyl compounds investigated. The working ranges in acetonitrile solution were found to vary from 0.25 to 79 mg/L with a correlation coefficient greater than 0.99, detection limits from 0.10 to 0.63 mg/L, and precision (relative standard deviation, n = 3) from 2.3 to 9.2%. Under an air flow rate of 0.3 L/min for a sampling time of 1 h, the working ranges varied from 0.030 to 11,000 microg/m3 and detection limits from 0.011 to 0.084 microg/ m3. The method has been successfully applied to monitor three carbonyl compounds in four urban and rural sites in Hong Kong and gave hourly readings of three carbonyl compounds for all the sites investigated with a separation time less than 25 min.

A new analytical procedure using a two-step sample preconcentration (solid-phase extraction (SPE) and field-amplified sample stacking) prior to separation by micellar electrokinetic capillary chromatography was developed for the determination of 14 pesticides such as aldicarb, carbofuran, isoproturon, chlorotoluron, metolachlor, mecoprop, dichlorprop, MCPA, 2,4-D, methoxychlor, TDE, DDT, dieldrin, and DDE in drinking water. Good recoveries of pesticides were obtained using SPE with sample pH adjusted to 2-3. Field-amplified sample stacking was found to give enrichment factors up to 30-fold preconcentration of various pesticides under reversed polarity at -2 kV for 50 s. The optimized background electrolyte (BGE) consisted of 50 mM sodium dodecyl sulfate (SDS), 10 mM borate buffer, 15 mM beta-cyclodextrin (beta-CD), and 22% acetonitrile at pH 9.6, running was under 25 kV and detection at 202 nm. Good linearity was obtained for all pesticides with detection limits down to 0.04-0.46 ng/mL and a working range of 0.1-40 ng/mL. The repeatabilities of migration time and peak area were satisfactory with relative standard deviations (RSDs) between 0.66 and 13.6% and 4.1 and 28%, respectively. All pesticides except dieldrin were found to be detected at concentrations at least tenfold lower than the World Health Organization (WHO) guideline values. The analytical procedure developed offers an economic method for fast screening of multiple pesticide residues in drinking water for health protection. It had been applied to determine carbofuran and MCPA in agricultural run-off water samples, giving satisfactory repeatabilities of 10 and 12%, respectively, with n=5 for the determination of pesticides in contaminated water samples.

A new capillary electrophoresis (CE) procedure was developed for simultaneous determination of ten oxoanions (CrO4(2-), SeO4(2-), MoO4(2-), WO4(2-), VO4(3-), SeO3(2-), As04(3-), TeO3(2-), TeO4(2-), and AsO3(3-)) which were baseline-separated from each other and from the interfering UV absorbing anions (NO3- and NO2-) commonly found in environmental water samples. The new background electrolyte system developed contained 5 mM potassium phosphate and 0.007 mM octadecyltrimethylammonium hydroxide, pH 11.2. The optimized working conditions were electrokinetic sampling at -5 kV for 10 s, running voltage at -15 kV with 5 microA current, and detection wavelength at 205 nm. No interference was observed for non-UV-absorbing anions and UV-absorbing anions up to 20 and 10 times higher concentrations respectively. The speed of analysis was fast, with a complete CE run within 6 min. Wide linear ranges (1-2,000 microg/L), good repeatability in migration time (relative standard deviation RSD 0.55-2.8%), satisfactory precision in peak area (RSD 3.8-5.6%) and peak height (RSD 3.9-5.3%) measurement, and detection limits (1-25 microg/L) sufficiently sensitive to detect oxoanions found in environmental water samples were obtained. The reliability of the CE procedure developed had been established by recovery test and parallel method determination using atomic absoprtion spectrophotometry for real river water sample.

A capillary electrophoresis (CE) procedure has been developed for the separation of 25 inorganic and organic acid anions using a buffer system consisting of 15 mM tris(hydroxymethyl)aminomethane, 3 mM 1,2,4-benzenetricarboxylic acid, 1.5 mM tetraethylenepentaamine (TEPA) and 20% methanol with pH adjusted to 8.4. A good separation of organic acids extracted from a mixture of Chinese traditional medicine (TCM) containing three herbs, Flos chrysthemi, Spica prunellae, and Folium mori was obtained using the procedure developed with satisfactory working range (0.20-77 mg/g), low detection limit (90-190 microg/g), and good repeatability (relative standard deviation 4.47-6.99%, n = 4). A satisfactory extraction of organic acids was achieved within 20 min using 0.1 M NaOH. The addition of TEPA to provide a reduced electroosmotic flow (EOF) environment was shown to remove interfering organic compounds extracted from TCM. The applicability of using organic acids as markers for determining the mixing ratio of constituent herbs for a TCM mixture was investigated using a three-component mixture with a 1:1:1 mixing ratio. A satisfactory mixing ratio of 1.04:1.09:0.98 was obtained using the methodology developed based on organic acids as markers. The application of our method for determining more complicated TCM mixtures has been discussed.

A new buffer system consisting of 30 mM hydroxylamine hydrochloride, 0.1 mM 1,10-phenanthroline, 1% methanol and pH 3.7 was optimized for simultaneous determination of water and acid leachable metals from respirable, fine and coarse air particulate matters. A reducing environment was used to resolve metal ions with variable oxidation states. A suitable counteranion was employed to enable acidic pH to be used and methanol was added to improve the resolution of the electropherograms and to achieve simultaneous determination of several metal ions. Compared to existing capillary electrophoresis (CE) buffers, the buffer developed, based on direct UV detection of ion-pair with weak interaction, gives improved resolution and sharper, more stable and well-resolved peaks. It detects total irons and solves interfering problems due to the variable oxidation states of iron in environmental samples. Compared to existing mostly alkaline CE buffers for metal analysis, the acidic nature of the buffer system developed makes the pretreatment step simpler and reduces the risk of reagent contamination. Satisfactory working ranges (15-5500 ppb) and detection limits (0.5-3 ppb) were obtained for leachable Zn, Cu, Co, Fe and Cd. The NIST 1648 urban particulate matters were found to leach out 2.53-42.8% water-extractable and 2.76-71.7% acid-extractable Zn, Cu, Fe and Cd. High iron contents, and lower copper and zinc concentrations were found in respirable suspended particulates (RSP) sampled in Hong Kong.

A neural network classification method has been developed as an alternative approach to the search/organization problem of large molecular databases. Two artificial neural systems have been implemented on a Cray supercomputer for rapid protein/nucleic acid sequence classifications. The neural networks used are three-layered, feed-forward networks that employ back-propagation learning algorithm. The molecular sequences are encoded into neural input vectors by applying an n-gram hashing method or a SVD (singular value decomposition) method. Once trained with known sequences in the molecular databases, the neural system becomes an associative memory capable of classifying unknown sequences based on the class information embedded in its neural interconnections. The protein system, which classifies proteins into PIR (Protein Identification Resource) superfamilies, showed a 82% to a close to 100% sensitivity at a speed that is about an order of magnitude faster than other search methods. The pilot nucleic acid system, which classifies ribosomal RNA sequences according to phylogenetic groups, has achieved a 100% classification accuracy. The system could be used to reduce the database search time and help organize the molecular sequence databases. The tool is generally applicable to any databases that are organized according to family relationships.

A new room temperature molten salt (RTMS) [1-methyl-3-ethylimidazolium/AlCl 3 /SnCl 2 (3:2:0.5)] was developed for depositing tin on a copper electrode. Different tin crystallites were deposited at different temperatures, giving widely different performances of the assembled lithium cell [Sn (Cu)/LiCl buffered MEICl-AlCl 3 RTMS/lithium] Tin film deposited at 50°C or higher gave a more desirable crystal structure and an improved performance than films obtained at lower temperatures. Both cyclic voltammetry and galvanostatic cycling show the formation of three major lithium-tin alloy phases corresponding to the phase transition of LiSn/Li 7 Sn 3 , Li 13 Sn 5 /Li 7 Sn 2 , and Li 7 Sn 2 /Li 22 Sn 5 . Increases in the charging and discharging capacities were found with the deposition of higher lithium-rich tin alloys though at the degradation of the irreversible capacity at the first cycle. The discharging capacity decreased rapidly, producing loose, expanded, and irregular crystallites upon cycling at a high current density (cdl (1.0 mA/cm 2 ). However, an average capacity of 140 mAh/g. coulombic efficiency around 85%, and more than 200 cycles were obtained at a low cd (0.4 mA/cm 2 ). The improvement is attributed to the deposition of small and regular tin crystallites that allows reversible insertion and removal of lithium from a more stable crystal structure without a significant volume change during cycling.

The deposition of lithium on aluminium leads initially to the formation of a solid solution, followed by the precipitation of various lithium/aluminium alloys. Several fundamental phenomena such as monolayer formation and nucleation were shown to affect the kinetics of the deposition process. In the present investigation, the cyclic voltammetric technique (fast) was used to study these phenomena. It is a very useful technique for the qualitative understanding of the deposition process and in its scanning coulometric modification, which is also utilised in this investigation, it can provide useful semiquantitative information.

The applicability of methyl acetate as a solvent for ambient temperature lithium secondary batteries was investigated using cyclic chronopotentiometry. Methyl acetate was found to be stable towards lithium-aluminium alloys and cycling up to more than 300 cycles was obtained with about 90% cycling efficiency. Water and other organic impurities have been identified in methyl acetate and a thorough purification procedure has been used to reduce these to acceptable levels. LiAsF6, LiPF6, LiClO4 and LiBF4 were investigated for use as supporting electrolytes and LiAsF6 was found to be the best in terms of cycling efficiency, longer cycling numbers and yielding the lowest corrosion capacity loss rate. The development of the LiAl anode upon cycling was observed in parallel with the reduction in nucleation polarization potential, the increase in cycling efficiency, the lowering of concentration polarization at the electrode surface and the more ready acceptance of lithium deposition at the developed electrode. The optimum conditions for the development of the LiAl anode were found to exist at a current density of 5 mA cm−2 and a charge density of 0.5 C cm−2.

The Thomsen Friedenreich (TF) antigen may be important for the detection and immunotherapy of a number of common cancers including breast cancer. Revealed on normal human erythrocytes by neuraminidase treatment, TF has been characterized as: β-D-Gal-(1–3)- α-GalNAc, attached to glycophorin or other glycoproteins through O-serine or O-threonine linkages (1). Tn, the TF precursor, is reported to be α-GalNAc-O-serine/ threonine. While TF is normally cryptic due to the presence of a terminal sialic acid residue, Tn is exposed in individuals with a recessive genetic disorder (2). Springer (1) has claimed expression of TF and Tn antigens on over 90% of cancers of the breast, lung and pancreas, although the nature of the molecules which bear these antigens and their exact structures has not been defined.

A method is described for the determination of copper in palm oil by differential-pulse anodic-stripping voltammetry after dry ashing. Only a few grams of sample are needed and the relative standard deviation is about 3% for oils with copper contents less than 100 p.p.b. (parts per 109).

The applicability of a copper(II) ion-selective electrode for the determination of the copper content of crude and hydrogenated palm oils was investigated. Dry ashing was used for destroying the organic matrix and a porcelain crucible was used as container. The recovery of copper in dry ashing and the leaching of copper from the internal glazing of a porcelain crucible were investigated. A complexing antioxidant buffer was used in order to minimise the interfering effect of iron(III) on the determination of copper(II). A direct potentiometric method can be applied to determine the copper content of palm oil at a concentration higher than 10 µg kg–1 in the presence of 30 mg kg–1 of iron.