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Using quantitative and qualitative methodology, a study was conducted on the process of case management performed by nurse case managers on a group of 45 post-discharged frail elderly patients in 2001-2002. The quantitative data provided the common reasons for client-initiated telephone calls to nurse case managers and the nurse case managers' interventions to these calls. Qualitative data yielded 9 major themes on which a sequential and dynamic process model of case management was conceptualized. Another 7 thematic descriptions on essential factors for the successful implementation of case management were configured in a dual-dimensional framework of staff and structural factors.

A 12-month randomised controlled trial was conducted in Hong Kong to evaluate the effectiveness of case management provided to a group of home-dwelling, frail elderly patients (control group: n = 47; intervention group: n = 45) in terms of utilisation of hospital services by these patients. Significant reductions (significance at P

An adaptive algorithm for blind identification of single-input multiple-output (SIMO) FIR systems is proposed. It is based on the one-step forward linear prediction (LP) technique and can be implemented by an RLS adaptation. Unlike most second-order statistics (SOS)-based approaches, the proposed solution does not require the computation of the correlation matrix or its inverse explicitly. The obtained results demonstrate that the proposed approach is able to deliver better performance compared with the typical batch algorithm. It is also observed that the proposed algorithm can tolerate the appearance of near common zeros among the subchannels.

In the paper, the idea of space-adaptive regularisation is introduced into the nonnegativity and support constraints recursive inverse filtering (NAS-RIF) algorithm for blind image restoration. A newly developed cost function is obtained by adding a space-adaptive regularisation term to the cost function of the NAS-RIF algorithm to prevent noise amplification and to reduce ringing artifacts. Compared to the original NAS-RIF algorithm, the improved NAS-RIF algorithm is particularly effective under low SNR conditions. Also, the experimental results show that the co-vergence characteristic of the improved NAS-RIF algorithm is much more stable and the converged solution is capable of providing an excellent estimate of the original image.

The problem of determining the AR order and parameters of a nonminimum phase ARMA model from observations of the system output is considered. The model is driven by a sequence of random variables which is assumed unobservable. A novel identification algorithm based on the second- and third-order cumulants of the output sequences is introduced. It performs order-recursively by minimising a well defined cost function. Strong convergence and consistency of the algorithm are proved and the weight of the cost function is balanced between the second-order and the third-order cumulants of output sequences. The influence of the weight on the estimation accuracy is also evaluated. Theoretical analyses and numerical simulations show that the proposed algorithm is satisfactory for both order and parameter identification of an AR model which is subordinate to a nonminimum phase ARMA model.

Photosynthetic electron transport in vivo was investigated in tobacco leaves pre-illuminated with strong light under conditions where Photosystem (PS) II repair was inhibited by lincomycin. Flash-induced redox changes of cytochrome b563, cytochrome f and plastocyanin, and the electrochromic (EC) signal (caused by a carotenoid band-shift due to charge separation across thylakoid membranes) from leaf segments were measured by deconvoluting absorbance changes at 520, 554, 564 and 575 nm. The EC signal was composed of easily separable fast and slow components. The fast EC signal decreased linearly with the loss of functional PS II centres, but there was a residual fast EC phase which was attributable to PS I centres alone. Inactivation of PS II centres by photoinhibitory light was also well-correlated with the quenching of variable fluorescence measured as the ratio of variable to maximum fluorescence, Fv/Fm. On complete photoinactivation of PS II centres, the slow rise of the flash-induced EC signal became more prominent, suggesting enhanced electrogenic charge transfer across the cytochrome bf complex as part of a path of electron flow involving PS I. Thus, both PS I and the cytochrome bf complex appeared to be fully functional after treatment of tobacco leaves with photoinhibitory light at room temperature. In totally photoinhibited leaf segments, the rate coefficients of cyt fIII re-reduction increased from 59 s-1 (+ lincomycin, no photoinhibitory light) to 130 s-1, and that of cytochrome b563 reduction also increased, from 270 s-1 to 500 s-1, suggesting that the prevailing plastoquinol concentration was higher after photoinhibitory light treatment. The source of the electrons entering the pool under these conditions was probably a high concentration of NADPH and reduced ferredoxin.

A novel neural network technique for electric load forecasting based on weather compensation is presented. The proposed method is a nonlinear generalisation of Box and Jenkins approach for nonstationary time-series prediction. A nonlinear autoregressive integrated (NARI) model is identified to be the most appropriate model to include the weather compensation in short-term electric load forecasting. A weather compensation neural network based on an NARI model is implemented for one-day ahead electric load forecasting. This weather compensation neural network can accurately predict the change of electric load consumption of the coming day. The results, based on Hong Kong Island historical load demand, indicate that this methodology is capable of providing more accurate load forecast with a 0.9% reduction in forecast error.

1. Mitochondria from Jerusalem artichoke (Helianthus tuberosus) tubers and Arum maculatum spadices caused a quenching of the fluorescence of 9-aminoacridine when mixed in a low-cation medium (approximately 1 mM-K+) and addition of chelators further decreased the fluorescence. Salts released the quenching of the 9-aminoacridine fluorescence and the efficiency of the release appeared to be mainly dependent on the valency of the cation (C3+ greater than C2+ greater than C+). 2. The results are consistent with the theory of charge screening and demonstrate that 9-aminoacridine is a convenient probe of the behaviour of cations on the membranes of mitochondria and in the diffuse layer associated with these membranes. 3. The concentration of salt required to achieve half-maximal release of quenching of 9-aminoacridine fluorescence was proportional to the concentration of mitochondria in the solution and theoretical considerations show this effect to be inherent in the Gouy-Chapman theory. 4. 9-Aminoacridine was removed from the bulk of the solution by the mitochondria to a far greater extent than was Na+ or K+, which is suggested to be due to the formation of bi- and poly-valent cations by aggregation of 9-aminoacridine molecules in the diffuse layer. This would have implications for the use of 9-aminoacridine to determine delta pH across membranes. 5. Jerusalem-artichoke mitochondria removed from 9-aminoacridine and Ca2+ from the bulk of the solution and required more ions to screen the membranes than did an equal concentration (mg of protein/ml) of Arum mitochondria, indicating that Jerusalem-artichoke mitochondria contain more negative charges per mg of protein.

Singapore and Hong Kong are two of the most advanced industrial countries in east and south-east Asia. Comparisons between them have often been made, and this article takes their social security systems as a subject for examination. It begins with a brief discussion of the social, economic and political structures of Singapore and Hong Kong, identifying their similarities and differences; this is followed by a comparison of their existing social security provisions and the functions they perform in the two societies. It is found that, while Singapore and Hong Kong are now both affluent enough to provide their workers with comprehensive income protection, industrialization in the two cities has not brought a corresponding development in their social security systems. Other considerations seem to be more important than the need for such measures.

Silica gel (100–200 mesh) can be coated with a stable layer of crosslinked polyethylenimine (PEI). The resulting material is useful in column chromatography for quantitative separation of adenine nucleotides. For example, 3′:5′-cyclic AMP can be separated from a mixture containing AMP, ADP, and ATP. A mixture of adenosine, AMP, ADP, and ATP can be resolved with quantitative recovery of components. Convenient separation of cytochrome c from albumin illustrates the applicability of this system to protein purification. PEI-Xama silica gel and PEI-glutaraldehyde silica gel have ion-exchange capacities of 0.27 and 0.21 meq/g, respectively. The materials are dimensionally rigid and chemically stable except in alkaline solutions (>pH 10) for prolonged periods.

Factors that may influence the extent of thylakoid membrane appression have been examined using lettuce (Lactuca sativa cv. Celtuce) grown under different irradiances. Electron microscopy and salt-induced chlorophyll fluorescence suggest that the percentage of membrane appression is increased in plants grown in low light (20 Wm(-2)) compared with those grown in high light (150 Wm(-2)). In high light plants surface charge, as measured by 9-aminoacridine, was found to be twice that measured in low light plants. There was a similar difference in ATPase activity of CF1 and in light saturated photophosphorylation. The chlorophyll content of LHC-2 as a proportion of the total chlorophyll was greatest in thylakoids of low light plants. Measurement of non-cyclic photophosphorylation rates suggested that membrane appression has a stimulatory role in the photophosphorylation process. The importance of these inter-related factors for the mechanism of thylakoid appression is discussed.

Several models have been proposed to describe germination rates, but most are limited in statistical analysis and biological meaning of indices. Therefore, a mathematical model is proposed to utilize the logistic function. The function was defined as an overall response including time, temperature, and the interaction between time and temperature. Cumulative germination percentages over time were used to develop the model. Germination tests were conducted on indiangrass (Sorghastrum nutans (L.) Nash) strain TG-2CF,' at constant temperatures of 9,12,15, 20,25, and 30 °C. The function fitted the observed data over six temperatures at r2 = 0-99. Time to reach 10% of final germination (Gim) increased from 2-5 d at 30 °C to 44-0 d at 9 °C, and Gt50 (time to reach 50% of final germination) increased from 3-6 d at 30 °C to 53-8 d at 9°C. True germination rate (% d~ ') for each temperature was maximum at Gt50. A linear model of 1/Gt50 versus temperature was used to estimate the base temperature of 8-3 °C for germination. An Arrhenius plot indicated a change occurred between 20 °C and 25 °C for temperature response of germination. Published data on hypocotyl growth of Cucumis melo L. were recalculated using the model. Absolute growth rates showed a temperature response similar to the published weighted-mean elongation rates. Base temperature for hypocotyl growth of C. melo was estimated as 8-8 °C. The proposed model proved to be useful in calculating and interpreting germination and growth kinetics.

A few rare hemoglobin variants with altered functional properties have been observed in Canadian subjects with either an erythrocytosis or mild anemia. These variants were Hb Alberta [β101(G3)Glu→Gly], Hb Linkoping [β36(C2)Pro→Thr], a new variant Hb Sunnybrook [β36(CE)Pro→Arg], and Hb Caribbean [β91(F7)Leu→Arg]. Short clinical descriptions of the subjects are given, the characterization of the variants is described in detail (except for Hb Alberta), while data from some functional analyses are provided. Comparisons with previously published data have been made and the unusual chromatographic property of two abnormal β chains in a reversed phase high performance liquid chromatographic system is reviewed.

The specific heat of a two-band model for superconducting transition metals containing nonmagnetic impurities is investigated. First, the change of the thermodynamic potential of the two-band model due to the existence of interband impurity scattering is derived by making use of the Green function theory. Based on this, it is found that the specific heat of a two-band superconductor containing nonmagnetic impurities is larger than that of a corresponding pure two-band superconductor at temperatures in the immediate vicinity of the transition temperature. The difference of these two specific heats is shown to be proportional to the density of impurities, the strength of the interband impurity scattering and the difference between the specific heat of a pure two-band superconductor with its d band in the superconducting state and its s band in the normal state and that of the same pure crystal with both its bands in the normal state.

The method of Bohm and Pines is adopted for the study of the ground-state energy as well as of the elementary excitations of a charged Bose gas. The ground-state energy thus obtained agrees with that of Girardeau. Based on the Bohm-Pines method and the Bogoliubov approximation, a detailed study of the interaction between particles and plasmons is carried out by making use of the linked-cluster method. The perturbation terms thus handled can be summed to infinite order. With the consideration of interaction, the ground-state energy of the system is corrected, though the correction is found to be negligibly small, and both the single-particle excitation spectrum and the plasmon excitation spectrum are obtained. The single-particle excitation spectrum is found to possess an energy gap, though different from that obtained by Foldy, and thus the system possesses the property of superconductivity. It is noticed that the Bogoliubov approximation adopted by Foldy and Girardeau is correct to the lowest order of the approximation. The energy gap in the single-particle excitation spectrum is found to be due to the long-range particle-plasmon interaction.

Green's-function techniques are applied to the investigation of phonon-assisted optical absorption in semiconductors. Different processes involved in phonon-assisted absorption are found, corresponding to different second-order diagrams in the expansion of the polarization function. Agreement is reached between the present theory and conventional perturbation theory. Some possible refinements are discussed.

Within the past few years the availability of digital computing equipment has provided the design engineer with a new and powerful tool for performing numerical calculations and logical decisions at high speed and low cost. Computer programs for product design may be divided into two characteristic types: performance programs for which the dimensions and other parameters are given as input, and synthesis programs for which the required performance specifications are given as input. Performance programs have been described in the literature for several kinds of power and industrial electric equipment. They are a useful and necessary prerequisite to design synthesis programs which appear to have found their first and most common application in power transformer design. In the opinion of the authors, an extension of the philosophy of design synthesis to the design of rotating machinery is perhaps more difficult, but still a practical venture. A list of programs in actual use for rotating machine design is presented. The features of one induction motor performance program are first described in some detail followed by a description of three programs for synchronous motor design. The combination of these three programs has many of the features of a complete synthesis program, but with sufficient compromise for practical operation on a medium-sized digital computer.

A two-band superconductor model with one normal d band and one superconducting s band in the presence of nonmagnetic impurities is investigated. The nonmagnetic impurities cause interband as well as intraband scattering. The phase transition temperature of the superconducting s band is obtained in the limit of low impurity density, and is found to be lower than that of the corresponding pure two-band superconductor.

An approximate equation is derived that is satisfied by the upper critical field of two-band superconductors containing nonmagnetic impurities at temperatures just above zero. On the basis of this equation, it is found that if both the $s$ band and the $d$ band are in the superconducting phase, the upper critical field is larger than that of the two-band superconductor with the $d$ band in the superconducting phase and the $s$ band in the normal phase, at temperatures just above zero.

The dependence of the excitonic insulator transition temperature on the shift in chemical potential due to the presence of various types of impurities (donors, acceptors or normal impurities) and on the change of band masses due to small crystal deformations is investigated in terms of a mathematical parameter, ηp, which involves all these physical factors. It is shown that both in the semiconductor region and in the semi-metal region, the transition temperature is independent of the sign of this parameter but is a maximum when this parameter is zero.

It is well known that plants growing in high light have different photosynthetic characteristics to those growing in low light, including higher rates of light saturated photosynthesis and higher rates of dark respiration. It has also been demonstrated that many species have the ability to change these characteristics in response to a change in the irradiance. In this preliminary report we show the relationship between changes in CO2 exchange, RuBP carboxylase activity and PSII fluorescence during adaptation to both higher and lower irradiance.

As is well known, MITCHELL’S theory (1966) for the mechanism of ADP phosphorylation postulates that a ‘high-energy state’, equivalent to an electrochemical potential gradient for protons (= proton-motive force, PMF), is an intermediate between electron transport and phosphorylation.

In the next three decades Hong Kong will face a rapidly aging population. It was estimated the number of older adults aged 60 or above In Hong Kong will be increased from 1 million in 2001 to approximately 1.6 million by 2015. In 2001 there were 1.2 million soon-to-be-old adults aged between 45 and 59. In a survey of 1867 soon-to-be old adults in 2000 we found that 21.5% of them planned to rely on welfare as their first or second methods to maintain their living after retirement. Based on this result we estimated that in the coming 15 years the percentage of welfare recipients in the aged population might increase 60% whereas the absolute number of elderly welfare recipients would be 2.5 times of the current ones. Further analysts indicated that compared with other soon-to-be old adults those who selected welfare as their first and second choice to secure retirement income were more likely to be unemployed to receive welfare to be lacked of family financial support (especially from adult children) to have lower income and financial asset and not to have any retirement protection provided by their current employers. (authors)