A new configuration of membrane stack for retrieval of nickel absorbed in resins

INTRODUCTION To meet the needs of wastewater recovery andreuse, ion exchange was commonly used especiallyfor the purification of electroplating rinse water con-taining nickel and other heavy metal ions (Koivula etal., 2000). Although ion exchange resins have manyadvantages over chemical precipitation, some draw-backs of the method are inevitable. When the ionexchange resins are saturated with metal ions, addi-tive chemical reagents (acid and alkali) are needed toregenerate the resins and…     

Science Letters:A new asymmetric watermarking scheme based on a real fractional DCT-I transform

INTRODUCTIONDue to the ease of transmitting digital data and copying without loss of quality, the unauthorized distribution of digital multimedia contents has be-come easy and popular. Digital watermarking is the most promising technique to protect the copyright of digital multimedia contents (Cox et al., 2001). Most of the proposed watermarking schemes are symmetric, in which keys for watermark detecting are identical to those for watermark embedding. Therefore, symmet-ric watermarking s…     

Science Letters:A modified chlorophyll absorption continuum index for chlorophyll estimation

INTRODUCTION Great advance has been achieved in vegetation characterization with remote sensing techniques. Most spectral vegetation indices (VIs) are usually calculated as the combinations of red and near-in- frared (NIR) reflectance because the information contained in a single spectral band is insufficient for characterizing vegetation status as vegetation exhibits unique reflectance properties in these bands. These VIs can be generally grouped into ratio indices and orthogonal indic…     

Science Letters: A current-differential-based method for improving dynamic characteristics of electromagnetic actuators

ontrol method is applied to a real gravure system which verifies the control performance.     

Science Letters: Application of new tissue microarrayer-ZM-1 without recipient paraffin block

The ZM-1 tissue microarrayer designed by our groups is manufactured in stainless steel and brass and contains many features that make TMA (tissue microarray) paraffin blocks construction faster and more convenient. By means of ZM-1 tissue microarrayer, biopsy needles are used to punch the donor tissue specimens respectively. All the needles with the punched specimen cylinders are arrayed into the array-board, with an array of small holes dug to fit the needles. All the specimen cylinders arraying and the TMA paraffin block shaping are finished in only one step so that the specimen cylinders and the paraffin of the TMA block can very easily be incorporated and the recipient paraffin blocks need not be made in advance, and the paraffin used is the same as that for conventional pathology purpose. ZM-1 tissue microarrayer is easy to be manufactured, does not need any precision location system, and so is much cheaper than the currently used instrument. Our method's relatively cheap and simple ZM- 1 tissue microarrayer technique of constructing TMA paraffin block may facilitate popularization of the TMA technology.     

Science Letters: A robust polysilicon-assisted SCR in ESD protection application

A novel polysilicon-assisted silicon-controlled rectifier (SCR) is presented and analyzed in this paper, which is fabricated in HHNEC's 0.18 μm EEPROM process. The polysilicon-assisted SCRs take advantage of polysilicon layer to help bypass electro-static discharge (ESD) current without occupying extra layout area. TLP current-voltage (Ⅰ-Ⅴ) measurement results show that given the same layout areas, robustness performance of polysilicon-assisted SCRs can be improved to 3 times of conventional MLSCR's. Moreover, one-finger such polysilicon-assisted SCRs, which occupy only 947 μm2 layout area, can undergo 7-kV HBM ESD stress. Results further demonstrate that the S-type Ⅰ-Ⅴcharacteristics of polysilicon-assisted SCRs are adjustable to different operating conditions by changingthe device dimensions. Compared with traditional SCRs, this new SCR can bypass more ESD currents and consumes smaller IC area.     

Science Letters:A new quantitative model of ecological compensation based on ecosystem capital in Zhejiang Province, China

Ecological compensation is becoming one of key and multidiscipline issues in the field of resources and environ-mental management. Considering the change relation between gross domestic product (GDP) and ecological capital (EC) based on remote sensing estimation, we construct a new quantitative estimate model for ecological compensation, using county as study unit,and determine standard value so as to evaluate ecological compensation from 2001 to 2004 in Zhejiang Province, China. Spatial differences of the ecological compensation were significant among all the counties or districts. This model fills up the gap in the field of quantitative evaluation of regional ecological compensation and provides a feasible way to reconcile the conflicts among benefits in the economic, social, and ecological sectors.     

Science Letters: On numerical calculation in symplectic approach for elasticity problems

The symplectic approach proposed and developed by Zhong et al. in 1990s for elasticity problems is a rational analytical method, in which ample experience is not needed as in the conventional semi-inverse method. In the symplectic space, elasticity problems can be solved using the method of separation of variables along with the eigenfunction expansion technique, as in traditional Fourier analysis. The eigensolutions include those corresponding to zero and nonzero eigenvalues. The latter group can be further divided into α-and β-sets. This paper reformulates the form of β-set eigensolutions to achieve the stability of numerical calculation, which is very important to obtain accurate results within the symplectic frame. An example is finally given and numerical results are compared and discussed.     

Science Letters:Two ancient rounds of polyploidy in rice genome

An ancient genome duplication (PPP1) that predates divergence of the cereals has recently been recognized. We report here another potentially older large-scale duplication (PPP2) event that predates monocot-dicot divergence in     

Science Letters:Demonstration of a new biosensing concept for immunodiagnostic applications based on change in surface conductance of antibodies after biomolecular interactions

Electrical conductivity in biomolecules and other large polymeric systems has become an important topic of current research. Schlag et al.(2000a; 2000b) demonstrated that charge migration in proteins is highly efficient although the mechanistic origin is still debated and largely unknown even though various models have been proposed by Weinkauf et al.(1995; 1996; 1997). According to them, the charge transfer between amino acids takes place by hole hopping between local sites of lowest ionizati…     

Science Letters: Transient expression of chicken alpha interferon gene in lettuce

We investigated the possibility of producing chicken alpha interferon (ChIFN-α) in transgenic plants.The cDNA encoding ChIFN-a was introduced into lettuce (Lactuca sativa L.) plants by using an agro-infiltration transient expression system.The ChIFN-α gene was correctly transcribed and translated in the lettuce plants according to RT-PCR and ELISA assays.Re-combinant protein exhibited antiviral activity in vitro by inhibition of vesicular stomatitis virus (VSV) replication on chicken embryonic fibroblast (CEF).The results demonstrate that biologically active avian cytokine with potential pharmaceutical ap-plications could be expressed in transgenic lettuce plants and that it is possible to generate interferon protein in forage plants for preventing infectious diseases of poultry.     

Science Letters:Detection of Catabacter hongkongensis in polluted European water samples

The Catabacteriaceae is a new bacterial family with a unique member: Catabacter hongkongensis is a strictly anaerobic, non-sporulating, Gram-positive coccobacillus that is phylogenetically related to some clostridial clusters. Little is known of its epidemiology and environmental distribution, but the inclusion of its 16S rRNA gene sequence in GenBank has allowed it to be detected qualitatively. As a first approach for prospective surveys, a real-time polymerase chain reaction (PCR) procedure to identify C. hongkongensis has been developed. The presence of Catabacteriaceae in 29 water bodies subjected to possible human or animal impact has been investigated. Four of them were positive. The results confirm that highly polluted water can contain C. hongkongensis.     

Science Letters:A novel way of liver preservation improves rat liver viability upon reperfusion

Background/aim:Currently, the liver is cold-preserved at 0～4 °C for experimental and clinical purposes. Here, we investigated whether milder hypothermia during the initial phase of the preservation period was beneficial for liver viability upon reperfusion. Methods:In the first set of experiments, rat livers were preserved either conventionally in clinically used histidine-trypthopan-ketoglutarate (HTK) solution (Group A:45 min and Group B:24 h) or by slow cooling HTK solution (from 13 °C to 3 °C) during the initial 45 min of preservation (Group C:24 h). In the second set of experiments, additional groups of livers were evaluated:Group BB—preservation according to Group B and Group CC—preservation according to Group C. Further, some livers were preserved at 13 °C for 24 h. Livers were then reperfused using a blood-free perfusion model. Results:Bile production was approximately 2-fold greater in Group C compared to Group B. Alanine transaminase (ALT) and aspartate transaminase (AST) release into perfusate were 2～3-fold higher in Group B compared to Group C. No significant differences were found in ALT and AST release between Group C and Group A. Livers in Group CC compared to Group BB exhibited significantly lower portal resistance, greater oxygen consumption and bromosulfophthalein excretion into bile and lower lactate dehydrogenase (LDH) release into perfusate. Histological evaluation of tissue sections in Group BB showed parenchymal dystrophy of hepatocytes, while dystrophy of hepatocytes was absent in Group CC. Livers preserved at 13 °C for 24 h exhibited severe ischemic injury. Conclusion:These results suggest that the conventional way of liver preservation is not suitable at least for rat livers and that slow cooling of HTK solution during the initial phase of cold storage can improve liver viability during reperfusion.     

A new local ablation for unresectable primary liver tumor： effect of electrothermal and electrochemical therapy on rat liver

Background： Electrochemical therapy （ECT） has been used to treat unresectable hepatic tumor. In order to improve its efficacy, we combined ECT with hyperthermia induced by electrothermal needle （ETN） （ETECT）. The aim of this study is to investigate the destructive effect of ETECT on normal rat liver. Methods： Twenty rats were randomized into 4 treatment groups （n=5 in each group）： control, ECT alone, hyperthermia alone and ETECT. Following the treatment, sections of the livers were histologically examined by light microscopy and the destructive volumes were measured with micrometer. Results： We found that the destructive volumes in ETECT group were the largest （P〈0.01）. In ETECT group coagulative necrosis was found in both anode and cathode areas, around which transition zones existed. The transition zones can only be seen when coulomb was increased in ECT group. Conclusion： ETECT was demonstrated to enhance the destructive effect of ECT. This study provides theoretical and experimental basis for a new local ablative treatment for unresectable primary liver tumor.     

Science Letters:Culture of Spirulina platensis in human urine for biomass production and O_2 evolution

INTRODUCTION For long distance manned space missions, bio- logical life support systems (BLSS) have to be in- troduced into the life support system to achieve regeneration of nutrient matter (Volker and Frank, 2001). Recently, many kinds of subsystems within BLSS have been proposed and experimented on solely or jointly, which include mainly higher plant, aquatic organisms (Volker and Frank, 2001), micro- organisms and microalgae (Gros et al., 2003). Mi- croalgae were incorporated in …     

Science Letters:Remediation of Cr(Ⅵ) in solution using vitamin C

The effectiveness of vitamin C in treating Cr(Ⅵ)-contaminated water is being evaluated. Cr(Ⅵ) is an identified pollutant of some soils and groundwater. Vitamin C, an important biological reductant in humans and animals, can be used to transform Cr(Ⅵ) to essentially nontoxic Cr(Ⅲ). The removal efficiency was 89% when the mass concentration of vitamin C was 80 mg/L in 60 min, and nearly 100% Cr(Ⅵ) was removed when the mass concentration was 100 mg/L. Our data demonstrated that the removal efficiency was affected by vitamin C concentration, the reaction temperature and the dissolved oxygen concentration.The reaction mechanism of Cr(Ⅵ) by vitamin C was presented. Our study opens the way to use vitamin C to remediate Cr(Ⅵ)-contaminated soils and groundwater.     

Science Letters:Radio frequency heating: a potential method for post-harvest pest control in nuts and dry products

The multi-billion dollar US tree nut industries rely heavily on methyl bromide fumigation for postharvest insect control and are facing a major challenge with the mandated cessation by 2005 of its use for most applications. There is an urgent need to develop effective and economically viable alternative treatments to replace current phytosanitary and quarantine practices in order to maintain the competitiveness of US agriculture in domestic and international markets. With the reliable heating block system, the thermal death kinetics for fifth-instar codling moth, Indianmeal moth, and navel orangeworm were determined at a heating rate of 18℃/min. A practical process protocol was developed to control the most heat resistant insect pest, fifth-instar navel orangeworm, in in-shell walnuts using a 27 MHz pilot scale radio frequency (RF) system. RF heating to 55℃ and holding in hot air for at least 5 min resulted in 100% mortality of the fifth-instar navel orangeworm. Rancidity, sensory qualities and shell     

Science Letters:Proteomic analysis of differentially expressed proteins in mice with concanavalin A-induced hepatitis

Objective:To find new protein biomarkers for the detection and evaluation of liver injury and to analyze the relationship between such proteins and disease progression in concanavalin A (Con A)-induced hepatitis.Methods:Twenty-five mice were randomly divided into five groups:an untreated group,a control group injected with phosphate buffered saline (PBS),and groups with Con A-induced hepatitis evaluated at 1,3 and 6 h.Two-dimensional gel electrophoresis (2-DE) and mass spectrometry (MS) were used to identif...     

Science Letters: Proteomic analysis of the serum in patients with idiopathic pulmonary arterial hypertension

Idiopathic pulmonary arterial hypertension (IPAH) is a rare disease of unknown etiology. The exact pathogenesis of pulmonary arterial hypertension is still not well known. In the past decades, many protein molecules have been found to be involved in the development of IPAH. With proteomic techniques, profiling of human plasma proteome becomes more feasible in searching for disease-related markers. In present study, we showed the protein expression profiles of the serum of IPAH and healthy controls after depleting a few high-abundant proteins in serum. Thirteen spots had changed significantly in IPAH compared with healthy controls and were identified by LC-MS/MS. Alpha-1-antitrypsin and vitronectin were down-regulated in IPAH and may be valuable candidates for further explorations of their roles in the development of IPAH.