Highly efficient light-harvesting ruthenium sensitizer for thin-film dye-sensitized solar cells

A high molar extinction coefficient heteroleptic ruthenium complex, incorporating an electron-rich hexylthio-terminal chain, has been synthesized and demonstrated as an efficient sensitizer for dye-sensitized solar cells. With this new sensitizer excellent power conversion efficiency is 11.5% and 4.7% obtained under an irradiation of full sunlight (air mass 1.5 global) in combination with a volatility electrolyte and solid state hole transporting material, respectively. The devices with low volatility electrolyte showed good stability under visible-light soaking at 60 degrees C during 1000 h of accelerated tests.

The structural and optical properties of InN nanodots grown with various V/III ratios by metal-organic chemical vapor deposition

Self-assembled InN nanodots have been prepared at 650 degrees C with various V/III ratios from 500 to 30 000 by metal-organic chemical vapor deposition (MOCVD). It is found that the dot density and morphological size as well as the optical properties all display drastic changes at V/III = 12 000. Generally, denser and smaller InN nanodots with higher emission energy and narrower linewidth were obtained when growth was conducted at V/III ratios slightly lower than 12 000 as compared to those at higher V/III ratios. The physical properties of our MOCVD-grown InN nanodots are sensitive to the surface structure and the morphology is very similar to molecular beam epitaxially grown GaN and InN films, which may be used as a guide to optimize the InN growth.

Treatment results and late complications of 556 patients with locally advanced nasopharyngeal carcinoma treated with radiotherapy alone

The aim of this study was to investigate the outcome in 556 patients with locally advanced nasopharyngeal carcinomas treated by radiation therapy alone. We observed 556 patients with stage T3-4 and N0-3 carcinoma who were treated by conventional radiotherapy alone between January and December 1999. The total dose delivered to the nasopharynx was 66-80 Gy over 6.5-8 weeks and to the neck lymph nodes 60-70 Gy over 6-7 weeks. The 5-year actuarial overall survival rate (OS) reached 66.41%. The OS was higher among stage T3 patients than among stage T4 patients (69.12% vs 58.96%, p = 0.0359). Among patients with stage N0, N1, N2 and N3 disease, the OS was 73.98%, 65.96%, 57.58% and 29.39%, respectively (p = 0.0009). Differences in disease-free survival, locoregional control rate and metastasis-free survival rate among each N stage were statistically significant, although this was not true of differences between stage T3 and T4 disease. Multivariate analysis showed that gender, age, T stage and N stage were significant prognostic factors for 5-year overall survival, disease-free survival, locoregional control and metastasis-free survival. We found that N stage is the dominant prognostic indicator for patients with locally advanced nasopharyngeal carcinoma receiving conventional radiation therapy alone, and that T stage was only a secondary correlative factor.

First Report of Stem-End Rot of Mango Caused by Phomopsis mangiferae in Taiwan

Mango (Mangifera indica L.) is grown on approximately 20,000 ha in Taiwan. It is an economically important crop and the income of many fruit farmers comes primarily from mango production. During 2006 and 2007, a stem-end rot disease was observed 1 week after harvest on 28 to 36% of stored mangoes picked from six orchards in the Pingtung, Tainan, and Kaoshiung regions. Two popular mango cultivars, Keitt and Irwin, showed greater susceptibility to this disease, while 'Haden' was found to be moderately susceptible. In storage, symptoms initially appeared as light-to-dark brown lesions surrounding peduncles. Rot symptoms advanced slowly but eventually penetrated the mesocarp, which consequently reduced the commercial value of fruits. The fungus formed abundant pycnidia (0.1 to 0.6 mm in diameter) on infected fruits in advanced stages of symptom development. Pieces of symptomatic fruits plated on acidified potato dextrose agar (PDA) and incubated at 25 ± 1°C consistently yielded the same fungus. A single conidial isolate was cultured. Pycnidia developed on PDA after continuous exposure to light for 9 to 14 days. On the basis of morphological characteristics, the fungus was identified as Phomopsis mangiferae L. (2,3). Pycnidia released two types of conidia: α-conidia (5 to 10 × 2.3 to 4.0 μm) were hyaline and oval to fusoid; and β-conidia (15.0 to 37.5 × 1.3 to 2.5 μm) were hyaline and filiform with characteristic curves. Conidiophores were hyaline, filiform, simple or branched, septate, and 15 to 75 μm long. Cultures incubated under continuous fluorescent light (185 ± 35 μE·m^-2·s^-1) at 25°C for 3 days were used as inoculum for pathogenicity tests. Five fruits from 'Keitt' were wounded with a sterilized scalpel and each wound (2 × 2 × 2 mm) was inoculated with either a 5-mm mycelium agar plug or a 0.5-ml spore suspension (10⁵ conidia per ml) of the fungus. Five wounded fruits inoculated with 5-mm PDA plugs or sterile water alone served as controls. Inoculated areas were covered with moist, sterile cotton. Fruits were enclosed in plastic bags and incubated at 24°C for 3 days. The test was performed three times. The same symptoms were observed on all inoculated fruits, whereas no decay was observed on control fruits. Reisolations from the inoculated fruits consistently yielded P. mangiferae, thus fulfilling Koch's postulates. This disease has previously been reported in Australia, Brazil, China, Cuba, India, Malaysia, and the United States (1). To our knowledge, this is the first report of P. mangiferae causing stem-end rot disease on mangoes in Taiwan. Our report necessitates taking preventive strategies in the field, prior to or after harvest, to contain postharvest losses in mangoes. References: (1) G. I. Johnson. Page 39 in: Compendium of Tropical Fruit Diseases. R. C. Ploetz et al., eds. The American Phytopathological Society. St. Paul, MN, 1994. (2) R. C. Ploetz, ed. Page 354 in: Diseases of Tropical Fruit Crops. CABI Publishing. Wallingford, UK, 2003. (3) E. Punithalingam. No. 1168 in: Descriptions of Pathogenic Fungi and Bacteria. CMI, Kew, Surrey, UK, 1993.

IL-10 promoter gene polymorphisms and sustained response to combination therapy in Taiwanese chronic hepatitis C patients

BACKGROUND AND AIMS

Host genetic factors may affect clinical outcomes of hepatitis C virus (HCV) infection; however, the possible mechanisms remain largely unknown. The role of immunopathogenesis in chronic hepatitis C leads to extensive exploration of host immunity including inflammatory cytokines.

METHODS

We examined interleukin 10 (IL-10) promoter gene polymorphisms at positions -1082, -819, and -592 relative to transcription start site and studied their association with response to 24 weeks of pegylated interferon plus ribavirin treatment in 143 chronic hepatitis C patients, of whom 97 (67.8%) achieved a sustained virologic response (SVR). In addition, 134 healthy adults were used as controls.

RESULTS

Of chronic hepatitis C patients, 111 (77.6%) were genotype 1 infection, 32 (22.4%) were genotype 2 infection. Patients with sustained virologic response were younger and had higher pretreatment ALT levels than those without. No statistical difference was found between chronic hepatitis C patients who achieved SVR or not in terms of gender, HCV genotype, pretreatment HCV RNA levels, and severity of liver disease. The serum IL-10 levels were comparable between healthy controls and chronic hepatitis C patients as well as between HCV patients with and without SVR. The distribution of IL-10 promoter gene polymorphisms at positions -1082, -819, and -592 relative to transcription start site was comparable between HCV patients and healthy controls as well as HCV patients with and without SVR. A high frequency of ATA haplotype of common IL-10 promoter gene SNPs was found in both chronic hepatitis C patients (70.3%) and healthy controls (69.8%). However, ATA haplotype was not associated with SVR in chronic hepatitis C patients.

CONCLUSIONS

Our data fail to demonstrate the influence of IL-10 promoter gene polymorphisms on the response to combination therapy in Taiwanese chronic hepatitis C patients. The impact of genetic variations in IL-10 haplotype on the response to anti-HCV treatment among different ethnic populations deserves further examination.

Enhanced mechanical properties of single-walled carbon nanotubes due to chemical functionalization

Recent studies have shown that the chemical functionalization of carbon nanotubes weakens most of their mechanical properties such as the critical buckling force under compression and the critical buckling moment under torsion. However, the mechanical properties including the critical bending curvature and the critical bending moment of single-walled carbon nanotubes can be improved after functionalization as shown in this paper. The molecular mechanics simulations reveal that there exists an optimum functionalization degree at which the critical curvatures of the functionalized carbon nanotubes reaches its maximum value. The critical curvatures of the carbon nanotubes increase with increasing functionalization degree below the optimum value, while the critical curvatures change little as the functionalization degree is beyond the optimum value. The influences of the bending directions and the aspect ratios of the functionalized carbon nanotubes are also examined via molecular mechanics simulations.

ZnO/Al2O3 core-shell nanorod arrays: growth, structural characterization, and luminescent properties

We report an aqueous chemical method to fabricate well-aligned ZnO/Al(2)O(3) nanocrystal (NC) core-shell nanorod arrays (NRAs). Structural characterization showed that the shell layers are composed of alpha-Al(2)O(3) nanocrystals. Photoluminescence measurements showed the enhancement of near-band-edge (NBE) emission of ZnO NRAs due to the presence of Al(2)O(3) NC shells. The Al(2)O(3) NC shell layer resulting in the flat-band effect near the ZnO surface leads to a stronger overlap of the wavefunctions of electrons and holes in the ZnO core, further enhancing the NBE emission. This approach should be very useful in designing many other core-shell NRAs for creating varieties of high-efficiency optoelectronic devices.

The chemically crosslinked metal-complexed chitosans for comparative adsorptions of Cu(II), Zn(II), Ni(II) and Pb(II) ions in aqueous medium

The chemically crosslinked metal-complexed chitosans were synthesized by using the ion-imprinting method from a chitosan with four metals (Cu(II), Zn(II), Ni(II) and Pb(II)) as templates and glutaraldehyde as a crosslinker. The influences of adsorption conditions, including molar ratios of crosslinker/chitosan and pH changes, were studied. They were used to investigate for comparative adsorptions of Cu(II), Zn(II), Ni(II) and Pb(II) ions in an aqueous medium. They were demonstrated the comparative adsorptions of Cu(II), Zn(II), Ni(II) and Pb(II) ions in the orders of the adsorbed amounts with templates: Cu(II) approximately Pb(II)>Zn(II) approximately Ni(II), Zn(II)>Cu(II) approximately Pb(II)>Ni(II), Ni(II)>Pb(II)>Zn(II)>Cu(II) and Pb(II) approximately Cu(II)>Zn(II)>Ni(II), respectively. In addition, the dynamical study showed to be well followed the second-order kinetic equation in the adsorption process. At the same time, the equilibrium adsorption data were fitted in three adsorption isotherm models, namely, Langmuir, Freundlich, and Dubinin-Radushkevich to show very good fits in the Langmuir isotherm equation for the monolayer adsorption process. The most important aspect of the chemically crosslinked metal-complexed chitosans with glutaraldehyde demonstrated to afford a higher adsorption capacity, and a more efficient adsorption toward metals in an aqueous medium.

Electrical and optoelectronic characterization of a ZnO nanowire contacted by focused-ion-beam-deposited Pt

We report on the transport properties of a single ZnO nanowire (NW) measured as a function of the length/square of the radius ratio via the transmission line method (TLM). The specific contact resistance of FIB-Pt contacts to the ZnO NWs is determined to be as low as 1.1 x 10(-5) Omega cm(2). The resistivity of the ZnO NWs is measured to be 2.2 x 10(-2) Omega cm. ZnO NW-based UV photodetectors contacted by FIB-Pt with a photoconductive gain as high as approximately 10(8) have been fabricated and characterized.

Polymer functionalized ZnO nanobelts as oxygen sensors with a significant response enhancement

A plasma-polymerized acrylonitrile (PP-AN)/ZnO nanobelt (NB) nanosensor reveals a better oxygen-sensing response than a bare ZnO NB nanosensor due to the sorption nature of the polymer. With the aid of UV light, significant response enhancements of PP-AN/ZnO NB nanosensors at low temperature have been observed since the effects of oxygen desorption/adsorption in PP-AN on the electron depletion region in the ZnO are significant. The minimum sensitivity at 150 degrees C is 16.6 ppm. This work permits its feasibility in areas where it is impossible to work at higher temperatures since lowering the working temperature of the sensor can avoid the structural deterioration, causing instability in the response.

Anemia treatment with Q2W darbepoetin alfa in patients with chronic kidney disease naïve to erythropoiesis-stimulating agents

OBJECTIVE

To evaluate the efficacy and safety of darbepoetin alfa dosed every-other-week (Q2W) to treat anemia in subjects with chronic kidney disease (CKD), not receiving dialysis, who were naïve to erythropoiesis-stimulating agent (ESA) therapy.

RESEARCH DESIGN AND METHODS

This was an open-label, multicenter, single-arm study enrolling ESA-naïve CKD subjects with baseline hemoglobin (Hb) < 11.0 g/dL. Q2W darbepoetin alfa treatment was initiated at a dose of 0.75 microg/kg and titrated to achieve and maintain Hb levels at 11.0-13.0 g/dL. Treatment was administered from week 1 to week 19.

MAIN OUTCOME MEASURES

The primary endpoint was the proportion of subjects who achieved Hb > or = 11 g/dL at any study visit, except in week 1. Hb levels, darbepoetin alfa dose, and safety were also assessed.

RESULTS

Of the 128 subjects who received at least one dose of darbepoetin alfa and of the subjects who completed the study, 118 (92%) and 112 (97%), respectively, achieved a Hb > or = 11 g/dL in a median time of 5 weeks. Median darbepoetin alfa dose at week 1 and at the time of achieving a Hb > or = 11 g/dL were 60 and 80 microg, respectively. Darbepoetin alfa was well-tolerated, and short-term adverse events were consistent with those expected in CKD subjects.

CONCLUSIONS

This study demonstrates that de novo Q2W darbepoetin alfa was effective in correcting and maintaining Hb levels in ESA-naïve subjects with CKD who were not receiving dialysis. Study limitations, including lack of a control arm for the study and multiple race information for subjects, must be considered in interpreting the results.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT00112008.

High precision high voltage divider and its application to electron beam ion traps

A high precision high voltage divider has been developed for the electron beam ion trap in Shanghai. The uncertainty caused by the temperature coefficient of resistance (TCR) and the voltage coefficient of resistance has been studied in detail and was minimized to the level of ppm (10(-6)) range. Once the TCR was matched between the resistors, the precision of the dividing ratio finally reached the ppm range also. We measured the delay of the divider caused by the capacitor introduced to minimize voltage ripple to be 2.35 ms. Finally we applied the divider to an experiment to measure resonant energies for some dielectronic recombination processes for highly charged xenon ions. The final energies include corrections for both space charge and fringe field effects are mostly under 0.03%.

Multiple stressor effects of herbicide, pH, and food on wetland zooplankton and a larval amphibian

Interactions of herbicides and natural environmental stressors such as pH and food availability are poorly understood. We tested a chemical formulation of triclopyr (Release) at environmentally relevant test concentrations (0.25 and 0.50 mg L(-1)) in combination with two levels of pH (pH 5.5 and 7.5), and two levels of food availability (high and low). Population level effects of each stressor alone and in combination with the others were investigated using Simocephalus vetulus, a zooplankton species, and Rana pipiens tadpoles (Gosner stage 25), both common to forest ponds and wetlands. Herbicide treatments resulted in significant decreases in survival of both test species as well as reproduction and development time for S. vetulus at levels 5-10x below predicted worst case environmental concentrations (2.6 mg L(-1)). This laboratory study demonstrates a probable risk of toxic effects of Release herbicide which may be significantly increased by low food availability and by low pH at environmentally relevant concentrations.

Impacts of peripheral obestatin on colonic motility and secretion in conscious fed rats

Obestatin, a novel putative 23-amino acid peptide, was found to be derived from a mammalian preproghrelin gene by using a bioinformatics approach. Although the effects of obestatin on food intake and upper gut motility remain controversial, no studies have been carried out to explore its influence on lower gut motility and secretion. We investigated the impacts of intravenous (IV) injection of obestatin on rat colonic motor and secretory functions. Colonic transit time, fecal pellet output, and fecal content were measured in freely fed, conscious rats, which were chronically implanted with IV and colonic catheters. To test the validity of this animal model, human/rat corticotropin-releasing factor (h/rCRF) served as a stimulatory inducer of colonic motility and secretion. IV injection of obestatin (45, 100, and 300 nmol/kg) did not affect the colonic transit time, whereas IV injection of h/rCRF (30 nmol/kg) effectively accelerated colonic transit time. IV obestatin, in every dose we tested, also did not modify fecal pellet output, frequency of watery diarrhea, total fecal weight, fecal dried solid weight, or fecal fluid weight in the first hour after injection. On the other hand, IV injection of h/rCRF significantly enhanced fecal pellet output, as well as increased the frequency of watery diarrhea, total fecal weight, fecal dried solid weight, and fecal fluid weight during the first hour after injection compared with IV saline controls. In conclusion, peripheral obestatin administration has no impact on colonic motility and secretion in conscious fed rats.

In vivo differentiation of aerobic brain abscesses and necrotic glioblastomas multiforme using proton MR spectroscopic imaging

BACKGROUND AND PURPOSE

Abscesses caused by aerobic bacteria (aerobic abscesses) can simulate intracranial glioblastomas multiforme (GBMs) in MR imaging appearance and single voxel (SV) proton MR spectroscopy of the central cavity. The purpose of our study was to determine whether MR spectroscopic imaging (SI) can be used to differentiate aerobic abscesses from GBMs. Our hypothesis was that metabolite levels of choline (Cho) are decreased in the ring-enhancing portion of abscesses compared with GBMs.

MATERIALS AND METHODS

Fifteen patients with aerobic abscesses were studied on a 1.5T MR scanner using an SV method and an SI method. Proton MR spectra of 15 GBMs with similar conventional MR imaging appearances were used for comparison. The resonance peaks in the cavity, including lactate, cytosolic amino acids, acetate, succinate, and lipids, were analyzed by both SV MR spectroscopy and MRSI. In the contrast-enhancing rim of each lesion, peak areas of N-acetylaspartate (NAA), choline (Cho), lipid and lactate (LL), and creatine (Cr) were measured by MRSI. The peak areas of NAA-n, Cho-n, and Cr-n in the corresponding contralateral normal-appearing (-n) brain were also measured. Maximum Cho/Cr, Cho/NAA, LL/Cr-n, and Cho/Cho-n and minimum Cr/Cr-n and NAA/NAA-n ratios in abscesses and GBMs were compared using the Wilcoxon rank sum test. After receiver operating characteristic curve analysis, diagnostic accuracy was compared.

RESULTS

Cytosolic amino acid peaks were found in the cavity in 7 of 15 patients with aerobic abscesses. Means and SDs of maximum Cho/Cr, Cho/NAA, LL/Cr-n, and Cho/Cho-n and minimum Cr/Cr-n and NAA/NAA-n ratios were 3.38 +/- 1.09, 3.88 +/- 2.13, 2.72 +/- 1.45, 1.98 +/- 0.53, 0.53 +/- 0.16, and 0.44 +/- 0.09, respectively, in the GBMs, and 1.77 +/- 0.49, 1.48 +/- 0.51, 2.11 +/- 0.67, 0.81 +/- 0.21, 0.48 +/- 0.2, and 0.5 +/- 0.15, respectively, in the abscesses. Significant differences were found in the maximum Cho/Cr (P = .001), Cho/NAA (P = .006), and Cho/Cho-n ratios (P < .001) between abscesses and GBMs. Diagnostic accuracy was higher by Cho/Cho-n ratio than Cho/Cr and Cho/NAA ratios (93.3% versus 86.7% and 76.7%).

CONCLUSION

Metabolite ratios and maximum Cho/Cho-n, Cho/Cr, and Cho/NAA ratios of the contrast-enhancing rim were significantly different and useful in differentiating aerobic abscesses from GBMs by MRSI.

Cortactin overexpression in the esophageal squamous cell carcinoma and its involvement in the carcinogenesis

The aim of this study is to examine whether dysregulated expression of cortactin occurs in esophageal squamous cell carcinoma (ESCC) and is involved in the development of ESCCs. An immunohistochemistry study for cortactin expression was performed on 46 pairs of surgically resected non-tumor and ESCC tumor tissues and murine tumors of esophagi induced by a carcinogen. The results show increased cortactin expression in 20 and in 22 to a lesser extent, out of a total 46 ESCC tumor tissues. Increased cortactin was also detected in the premalignant lesions, the early stage dysplasia and carcinoma in situ, of ESCC tumor tissues. Differential polymerase chain reaction results showed slight increases in the EMS1 gene only in two of 10 ESCC tumor tissues, suggesting that EMS1 gene amplification is not the only mechanism for cortactin overexpression. In the mouse model induced by treatment with 4-nitroquinoline 1-oxide and arecoline, increased cortactin was detected in the epithelia with hyperkeratosis, papillomas, and ESCCs with invasion into the submucosa, respectively. Overall, we observed cortactin overexpression in early and late stages of human ESCCs and carcinogen-induced murine ESCCs, suggesting a role for cortactin in esophageal carcinogenesis.

First Report of Fruit Rot of Strawberry Caused by an Alternaria sp. in Taiwan

In March 2005, a fruit rot disease was found in several commercial strawberry (Fragaria × ananassa Duchesne) fields at Fongyuan, 24.25°N, 120.72°E, in Taichung County in central Taiwan. The disease was rare and was negligible in most cultivated areas. However, disease incidence has increased by 4 to 5% over the last 2 years and causes significant postharvest losses. In storage, symptoms on berries include light brown-to-black, sunken, irregularly shaped lesions. The lesions gradually enlarge and become firm with a dark green-to-black, velvety surface composed of mycelia, conidiophores, and conidia. Twelve single conidial isolates (AF-1 to AF-12) of a fungus were isolated by placing portions of symptomatic fruit from four locations onto acidified potato dextrose agar (PDA) and incubating at 24 ± 1°C. One isolate from each of the four locations, AF-2, 6, 9, and 12, was selected for identification and pathogenicity studies. The fungus was identified as an Alternaria sp. according to the morphological descriptions of A. tenuissima (2,3). Conidiophores were simple or branched, straight or flexuous, septate, pale to light brown, 3.0 to 5.0 μm in diameter, and bore two to six conidia in a chain. Conidia were dark brown, obclavate or oval, and multicellular with seven transverse (in most cases) and numerous longitudinal septa. Conidia were 15.5 to 56.5 μm (average 35.0 μm) long × 6.0 to 15.0 μm (average 11.0 μm) wide at the broadest point. The pathogen was consistently isolated from berries in the field or in storage. Pathogenicity tests were conducted by inoculating 12 surface-sterilized berries with each of the four isolates. Approximately 300 μl of a spore suspension (2 × 10⁵ conidia per ml) was placed at two points on the uninjured surface of each fruit and allowed to dry for 5 min. Control fruits were treated with sterile water. The berries were then enclosed in a plastic bag and incubated at 24 ± 1°C for 2 days. Disease symptoms similar to those described above were observed on 95% of inoculated berries 3 days after inoculation, while no symptoms developed in control berries. Reisolation from the inoculated berries consistently yielded the Alternaria sp. described above. Pathogenicity tests were performed three times. Previously, strawberry fruit rot caused by A. tenuissima was reported from Florida (2) and Malaysia (1), however, to our knowledge, this is the first report of fruit rot of strawberry caused by a species of Alternaria in Taiwan. References: (1) W. D. Cho et al. List of Plant Diseases in Korea. Korean Society of Plant Pathology, 2004. (2) C. M. Howard and E. E. Albregts. Phytopathology 63:938, 1973. (3) R. D. Milholland. Phytopathology 63:1395, 1973.

Good death study of elderly patients with terminal cancer in Taiwan

OBJECTIVES

Over half of all terminal cancer patients in Taiwan are 65 or older, thus demonstrating the importance of terminal care for elderly people. This study investigates the good death status of elderly patients with terminal cancer, comparing the differences in the degree of good death among elderly and younger groups, and exploring the factors related to the good death score.

METHODS

Three hundred and sixty-six patients with terminal cancer admitted to a palliative care unit were enrolled. Two structured measurements, the good death scale and the audit scale for good death services, were used as the instruments in the study.

RESULTS

The scores of individual items and of the good death scale were increased significantly in both elderly (n = 206, 56.3%) and younger (n = 160, 43.7%) groups from the time of admission to just prior to death. However, the elderly group had significantly lower scores in 'awareness' (t = -3.76, P < 0.001), 'propriety' (t = -2.92, P < 0.01) and 'timeliness' (t = -2.91, P < 0.01) than the younger group prior to death. Furthermore, because of a lack of truth-telling, the elderly group also had significantly lower scores than the younger group in both 'respect for autonomy' and 'decision-making participation' (t = -2.17, P < 0.05; t = -2.21, P < 0.05, respectively). Multiple regression analysis revealed that 'respect for autonomy' (OR = 1.22, 95% CI = 0.76-1.67) and 'verbal support '(OR = 0.93, 95% CI = 0.34-1.51) were two independent correlates of the good death score in the elderly group.

CONCLUSION

The dilemma of truth-telling compromises the autonomy of the elderly patients with terminal cancer and consequently affects their good death scores. The palliative care team should emphasize the issue of truth-telling in the process of caring for terminally ill cancer patients, especially elderly patients.

Comparative adsorption of Cu(II), Zn(II), and Pb(II) ions in aqueous solution on the crosslinked chitosan with epichlorohydrin

The crosslinked chitosans synthesized by the homogeneous reaction of chitosan in aqueous acetic acid solution with epichlorohydrin were used to investigate the adsorptions of three metals of Cu(II), Zn(II), and Pb(II) ions in an aqueous solution. The crosslinked chitosan characterized by 13CNMR, SEM, and elemental analysis, and the effects of pH and anion on the adsorption capacity were carried out. The dynamical study demonstrated that the adsorption process was followed the second-order kinetic equation. The results obtained from the equilibrium isotherms adsorption studies of three metals of Cu(II), Zn(II), and Pb(II) ions by being analyzed in three adsorption models, namely, Langmuir, Freundlich, and Dubinnin-Radushkevich isotherm equations, indicated to be well fitted to the Langmuir isotherm equation under the concentration range studied, by comparing the linear correlation coefficients. The order of the adsorption capacity (Qm) for three metal ions was as follows: Cu2+>Pb2+>Zn2+. This technique for syntheses of the crosslinked chitosans with epichlorohydrin via the homogeneous reaction in aqueous acetic acid solution showed that the adsorptions of three metal ions in aqueous solution were followed the monolayer coverage of the adsorbents through physical adsorption phenomena.

Determination of particulate-bound formaldehyde from burning incense by solid phase microextraction

This work studied the feasibility of using a solid phase microextraction (SPME) fiber for sampling and analysis of gaseous formaldehyde as well as particulate-bound formaldehyde from burning Chinese incense. The SPME fiber with PDMS/DVB coating were partially coated with o-(2,3,4,5,6-pentafluorobenzyl)-hydroxylamine hydrochloride (PFBHA), and used for sampling formaldehyde. The sampling rate for formaldehyde and its dependence on temperature, relative humidity and sampling time were observed. The same PFBHA treated fibers were, in parallel, exposed to incense burning smoke with pre-filtration and without pre- filtration for 0.5-1 min. The NIOSH method 2541 using an XAD-2 tube at a flow rate of 0.1 Lpm was also applied for sampling simultaneously. The results demonstrate that commercially available PDMS/DVB fibers partially coated with PFBHA are capable of sampling the gas phase of formaldehyde as well as particulate-bound formaldehyde. The determined level of formaldehyde was close to the result obtained by the NIOSH method 2541. However, a reduction of the fiber's formaldehyde loading capacity in the aerosol sampling in comparison with gas sampling was noticed. This indicates that the particulate characteristics, and their bound chemicals other than formaldehyde may influence the maximum loading capacity of formaldehyde, and some characteristic particulates in high concentrations may even deteriorate the fiber coating.

Application of Klebsiella oxytoca immobilized cells on the treatment of cyanide wastewater

Klebsiella oxytoca, isolated from cyanide-containing industrial wastewater, has been shown to be able to biodegrade cyanide to non-toxic end products. The technology of immobilized cells can be applied in biological treatment to enhance the efficiency and effectiveness of biodegradation. In this study, potassium cyanide was used as the target compound and both alginate and cellulose triacetate techniques were applied for the preparation of immobilized cells. Results from this study show that KCN can be utilized as the sole nitrogen source by K. oxytoca. The free suspension systems reveal that the cell viability was highly affected by initial KCN concentration and pH. Results show that immobilized cell systems could tolerate a higher level of KCN concentration and wider ranges of pH. In the batch experiments, the maximum KCN removal efficiencies using alginate and cellulose triacetate immobilized beads were 0.108 and 0.101mM h(-1) at pH 7, respectively. Results also indicate that immobilized system can support a higher biomass concentration. Complete KCN degradation was observed after the operation of four consecutive degradation experiments with the same batch of immobilized cells. This suggests that the activity of immobilized cells can be maintained and KCN can be used as the nitrogen source throughout KCN degradation experiments. The maximum KCN removal rates using alginate and cellulose triacetate immobilized beads in continuous-column system were 0.224 and 0.192mMh(-1) with initial KCN concentration of 3mM, respectively. Results indicate that the immobilized cells of K. oxytoca would be applicable to the treatment of cyanide-containing wastewaters.

First Report of Gummosis Disease of Plum (Prunus salicina) Caused by a Botryosphaeria sp. in Taiwan

Plum (Prunus salicina Lindell) is grown on more than 3,870 ha in Taiwan. In 2004, a gummosis disease was observed on plum in the Ming Jian Region of Nantou County (120.675°E, 23.919°N), with 15% of the trees affected. Infections started on the current year's growth, primarily through lenticels, and formed small, sunken, discolored lesions. At later stages, white gum exuded from the lesions. Circular to oval, brown, necrotic areas were seen on the inner bark. Severely infected twigs showed defoliation and dieback. During the winter months, numerous black pycnidia or perithecia formed on infected twigs. Single conidial isolates of the pathogen were obtained from diseased twigs on acidified potato dextrose agar (PDA) and incubated at 25 ± 1°C for 3 days. On the basis of morphological traits, the fungus was identified as a Botryosphaeria sp. according to the CMI descriptions of Botryosphaeria ribis (3). Conidia (14.2 to 26.8 × 4.3 to 7.2 μm) were single celled, hyaline, and spindle shaped. Asci (105 to 135 × 12.5 to 15.5 μm) were hyaline, clavate, and bitunicate. Ascospores (18 to 22 × 7.0 to 8.2 μm) were hyaline and spindle shaped or fusoid. For pathogenicity tests, inoculum was prepared by culturing the fungus on PDA under continuous fluorescent light (128 ± 25 μE·m^-2·s^-1) at 25°C for 3 days. Two twigs on each of six trees were inoculated. Sharp incisions (3 × 3 × 3 mm) were made on healthy twigs (12 to 15 months old) with a sterilized scalpel and inoculated with either a 5-mm mycelial disc or 0.5 ml of a conidial suspension (10⁵ conidia/ml) of the fungus. Inoculated areas were covered with moist, sterile cotton and the entire twigs were enclosed in plastic bags. Twigs inoculated with 5-mm PDA discs or sterile water alone served as controls. The symptoms described above were observed on all inoculated twigs 14 days after inoculation, whereas control twigs did not develop any disease symptoms. Reisolation from the inoculated twigs consistently yielded the Botryosphaeria sp., thus fulfilling Koch's postulates. Botryosphaeria spp. have been reported to cause stem blight of many plants in temperate and tropical regions of the world (4). In Taiwan, B. dothidea has been reported as the causal agent of gummosis disease of peach (1) and fruit ring rot of pear (2); however, to our knowledge, this is the first report of a Botryosphaeria sp. causing gummosis of plum. References: (1). Y. Ko et al. Plant Pathol. Bull. 1:70, 1992. (2) Y. Ko et al. Plant Prot. Bull. (Taiwan) 35:211, 1993. (3) E. Punithalingam and P. Holliday. No. 395 in: Descriptions of Pathogenic Fungi and Bacteria. CMI, Kew, Surrey, UK, 1973. (4) W. A. Sinclair et al. Diseases of Trees and Shrubs. Cornell University Press, Ithaca, NY, 1987.

Sphenoid sinus osteoma at the sella turcica associated with empty sella: CT and MR imaging findings

SUMMARY

A 50-year-old woman presented with intermittent headache for the past few years. A paranasal sinus CT scan showed a diffusely calcified lesion at the roof of the sphenoid sinus and sella turcica, with the sellar floor bony cortex involved. Empty sella was noted. MR imaging revealed a soft-tissue lesion with low signal intensity on T1-weighted images, high signal intensity on T2-weighted images, and heterogeneous enhancement on postgadolinium images. Histologic examination revealed an osteoma composed of mature lamellar bone.

Application of in situ biosparging to remediate a petroleum-hydrocarbon spill site: field and microbial evaluation

In this study, a full-scale biosparging investigation was conducted at a petroleum-hydrocarbon spill site. Field results reveal that natural attenuation was the main cause of the decrease in major contaminants [benzene, toluene, ethylbenzene, and xylenes (BTEX)] concentrations in groundwater before the operation of biosparging system. Evidence of the occurrence of natural attenuation within the BTEX plume includes: (1) decrease of DO, nitrate, sulfate, and redox potential, (2) production of dissolved ferrous iron, sulfide, methane, and CO(2), (3) decreased BTEX concentrations along the transport path, (4) increased microbial populations, and (5) limited spreading of the BTEX plume. Field results also reveal that the operation of biosparging caused the shifting of anaerobic conditions inside the plume to aerobic conditions. This variation can be confirmed by the following field observations inside the plume due to the biosparging process: (1) increase in DO, redox potential, nitrate, and sulfate, (2) decrease dissolved ferrous iron, sulfide, and methane, (3) increased total cultivable heterotrophs, and (4) decreased total cultivable anaerobes as well as methanogens. Results of polymerase chain reaction, denaturing gradient gel electrophoresis, and nucleotide sequence analysis reveal that three BTEX biodegraders (Candidauts magnetobacterium, Flavobacteriales bacterium, and Bacteroidetes bacterium) might exist at this site. Results show that more than 70% of BTEX has been removed through the biosparging system within a 10-month remedial period at an averaged groundwater temperature of 18 degrees C. This indicates that biosparging is a promising technology to remediate BTEX contaminated groundwater.

First Report of Gray Leaf Spot of Mango (Mangifera indica) Caused by Pestalotiopsis mangiferae in Taiwan

Mango (Mangifera indica L.; family Anacardiaceae) is one of the world's most important fruit crops and is widely grown in tropical and subtropical regions. Since 2001, a leaf spot disease was found in mango orchards of Taiwan. Now, the disease was observed throughout (approximately 21,000 ha) Taiwan in moderate to severe form, thus affecting the general health of mango trees and orchards. Initial symptoms were small, yellow-to-brown spots on leaves. Later, the irregularly shaped spots, ranging from a few millimeters to a few centimeters in diameter, turned white to gray and coalesced to form larger gray patches. Lesions had slightly raised dark margins. On mature lesions, numerous black acervuli, measuring 290 to 328 μm in diameter, developed on the gray necrotic areas. Single conidial isolates of the fungus were identified morphologically as Pestalotiopsis mangiferae (Henn.) Steyaert (2,3) and were consistently isolated from the diseased mango leaves on acidified (0.06% lactic acid) potato dextrose agar (PDA) medium incubated at 25 ± 1°C. Initially, the fungus grew (3 mm per day) on PDA as a white, chalky colony that subsequently turned gray after 2 weeks. Acervuli developed in culture after continuous exposure to light for 9 to 12 days at 20 to 30°C. Abundant conidia oozed from the acervulus as a creamy mass. The conidia (17.6 to 25.4 μm long and 4.8 to 7.1 μm wide) were fusiform and usually straight to slightly curved with four septa. Three median cells were olivaceous and larger than the hyaline apical and basal cells. The apical cells bore three (rarely four) cylindrical appendages. Pathogenicity tests were conducted with either 3-day-old mycelial discs or conidial suspension (10⁵ conidia per ml) obtained from 8- to 10-day-old cultures. Four leaves on each of 10 trees were inoculated. Before inoculation, the leaves were washed with a mild detergent, rinsed with tap water, and then surface sterilized with 70% ethanol. Leaves were wounded with a needle and exposed to either a 5-mm mycelial disc or 0.2 ml of the spore suspension. The inoculated areas were wrapped with cotton pads saturated with sterile water and the leaves were covered with polyethylene bags for 3 days to maintain high relative humidity. Wounded leaves inoculated with PDA discs alone served as controls. The symptoms described above were observed on all inoculated leaves, whereas uninoculated leaves remained completely free from symptoms. Reisolation from the inoculated leaves consistently yielded P. mangiferae, thus fulfilling Koch's postulates. Gray leaf spot is a common disease of mangos in the tropics and is widely distributed in Africa and Asia (1-3); however, to our knowledge, this is the first report of gray leaf spot disease affecting mango in Taiwan. References: (1) T. K. Lim and K. C. Khoo. Diseases and Disorders of Mango in Malaysia. Tropical Press. Malaysia, 1985. (2) J. E. M. Mordue. No. 676 in: CMI Descriptions of Pathogenic Fungi and Bacteria. Surrey, England, 1980. (3) R. C. Ploetz et al. Compendium of Tropical Fruit Diseases. The American Phytopathological Society. St. Paul, MN, 1994.

First Report of White Root Rot of Japanese Serissa Caused by Rosellinia necatrix in Taiwan

Japanese serissa (Serissa japonica (Thunb.) Thunb.) is a very popular ornamental in Taiwan. During the summer of 2005, serissa plants in a central Taiwan nursery had decaying roots, leaf yellowing, and were wilting. Wilted plants had white fan-like mycelium under the bark. The disease caused 70% loss of seedlings at the nursery. Associated synnemata were rigid, erect, dark, setaceous, 0.8 to 2.1 mm long, 90 to 200 μm wide, and tapering to enlarged whitish gray heads composed of geniculate conidiophores and conidia. Conidia were 3.1 to 5.8 × 2.6 to 3.4 μm, unicellular, hyaline, and subglobal with a truncated base. Root rots were washed, disinfested for 1 min in 0.5% NaOCl, cut into 3 mm³ pieces, plated on Merck (Darmstadt, Germany) potato dextrose agar (PDA) amended with 100 ppm of ampicillin (Sigma, St. Louis, MO), and incubated at 24°C in the dark until hyphae emerged. Single hyphal tips were transferred to PDA, and two isolates were established as pure cultures. Mycelia were cut, stained with 1% cotton blue in lactophenol, and pear-shaped hyphal swellings adjacent to the septa were observed. According to these hyphal, synnematal, and conidial characteristics, the fungus was identified as Dematophora necatrix Hartig, the anamorph of Rosellinia necatrix Prill. Inoculum for pathogenicity tests were produced on oat-wheat medium composed of 20 ml of oat grain and 20 ml of wheat grain, mixed, and soaked in water for 3 h. The grains were placed in 200-ml flasks, autoclaved at 121°C for 30 min, inoculated with two isolates of D. necatrix separately, and grown for 14 days. Six 3-month-old Japanese serissa seedlings were grown in pots. The grain inoculum was added to unsterilized field soil and the plants were transplanted into this mix. Control plants were transplanted into a similar mix without the inoculum. Two replicates were used for a total of 24 inoculated plants and 24 control plants. All plants were kept in a growth chamber at 25 to 35°C with 20 min of irrigation per day, 12 h of irradiation, and relative humidity at more than 95%. Inoculated plants developed root rots after 1 month, and after 4 months, all plants were dead, while control plants remained healthy. D. necatrix was reisolated, hyphal characteristics confirmed, and synnemata were observed on collars of dead plants. The teleomorph was not formed by our cultures, and the identification of Rosellinia necatrix was confirmed by molecular studies. The nuclear ribosomal internal transcribed spacer (ITS) amplified with two primers, ITS1 and ITS4, from our representative isolate demonstrated 99.63, 99.81, and 99.27% similarity to two R. necatrix isolates from Japan and one R. necatrix isolate from Italy, respectively. This disease has been reported on many species of plants (1), but to our knowledge, this is the first report of white root rot of Japanese serissa seedlings caused by R. necatrix in Taiwan. Reference: (1) S. T. Su et al. List of Plant Diseases in Taiwan. The Phytopathological Society of the Republic of China, 2002.

The influence of concomitant HIV infection on the serological diagnosis of primary syphilis in southern Africa

The authors investigated the utility of both a nontreponemal (RPR) test and a treponemal (FTA-ABS) test for the diagnosis of primary syphilis during the emergence of the HIV epidemic in southern Africa. The serological tests were performed on 868 patients with genital ulcerations, seen in five centres. While primary syphilis was diagnosed by multiplex PCR in 163 cases (18.8%), the overall RPR and FTA-ABS seroprevalences were 24.3% and 51.5% respectively. The sensitivities of the RPR and FTA-ABS to detect primary syphilis were 69.3% and 89.6% respectively, while the specificities were 86.1% and 58.5% respectively. The performance characteristics of these tests were influenced negatively by concomitant HIV infection and the presence of other genital ulcer disease pathogens in lesions found to be Treponema pallidum PCR positive.

Epidermoid cyst of the testis

Epidermoid cysts, though having a variable sonographic appearance, may present with an onion peel configuration, that is, concentric rings of alternating hyperechogenicities and hypoechogenicities. The absence of vascular flow on colour Doppler sonography is also consistent with the avascular nature of these lesions. By combining these two sonographic features and the absence of biochemical tumour marker, preoperative diagnosis of epidermoid cyst is possible and may prompt a testis sparing surgery rather than orchidectomy.

A general review of competition genetic effects with an emphasis on swine breeding

A review of previous studies is presented on estimates of genetic parameters and responses to selection with traditional breeding approaches, on correlations between agonistic behavior and growth performance, and on theoretical frameworks for selection incorporating interactions among individuals and on practical methods for incorporating competition effects in breeding programs.

First Report of Southern Blight of Silvery Messerschmidia Seedlings in Taiwan

Silvery messerschmidia, Messerschmidia argentea (L.) Johnston, of the Boraginaceae, is indigenous to Taiwan and grown as an ornamental, for windbreaks, or as a shade tree. During the summer of 2005, a sudden wilt of 1-year-old plants was observed in a nursery in central Taiwan. Initial symptoms included stem necrosis at the collar, leaf yellowing, and tan discoloration of leaves. As stem necrosis progressed, infected plants wilted, defoliated, and died. Necrotic tissues were covered with whitish mycelium with clamp connections that formed reddish brown spherical (1 to 2.2 mm in diameter) sclerotia. A fungus was consistently recovered from the interface of diseased and healthy stem tissue, disinfested for 1 min in 0.5% NaOCl, and plated on Difco (Sparks, MD) potato dextrose agar (PDA) amended with 100 ppm of ampicillin. Pure cultures were prepared by transferring single hyphal tips to PDA, and Sclerotium rolfsii (Sacc.) was identified (1). Pathogenicity of two S. rolfsii isolates was confirmed by inoculating 3-month-old silvery messerschmidia seedlings grown in pots. Inoculum consisted of a single agar disk of a 7-day-old culture used per pot or a single sclerotium produced in 10 days on PDA and added per pot. Both the mycelium on the 0.5-cm-diameter agar plug and the sclerotium touched the base of the plant stem. Four plants were inoculated with mycelia, four with sclerotia, and four were noninoculated controls. All plants were kept in a growth chamber at 25 to 35°C with relative humidity of more than 95%. Initially, the basal stems were covered by whitish mycelia growth with a fanlike pattern from the inoculum, and brown, water-soaked necrotic lesions developed near the soil line. Inoculated plants developed symptoms within 4 days, wilted gradually in 7 days, and all were eventually killed in 11 days. Plants inoculated with sclerotia developed disease at a slower rate and control plants remained symptomless. Sclerotia developed on diseased tissues and S. rolfsii was reisolated. This disease has been observed on many species of plants (2), but to our knowledge, this is the first report of southern blight of silvery messerschmidia seedlings caused by S. rolfsii in Taiwan. References: (1) R. K. Jones and D. M. Benson, eds. Diseases of Woody Ornamentals and Trees in Nurseries. The American Phytopathological Society, St. Paul, MN, 2001. (2) Y. P. Tsai, ed. List of Plant Diseases in Taiwan. The Plant Protection Society of the Republic of China and The Phytopathological Society of the Republic of China, 1991.

First Report of Gray Mold Disease of Sponge Gourd (Luffa cylindrica) Caused by Botrytis cinerea in Taiwan

A disease of sponge gourd (Luffa cylindrica (L.) Roem., family Cucurbitaceae) has become a serious threat to sponge gourd production since 2003 in central Taiwan. Initially, symptoms appear as small, brown spots on the flower petals that spread to the entire flower and cause blossom blight within 2 to 3 days. Subsequently, the pathogen develops abundant mycelium and moves from the petals onto the fruits causing blossom end rot and fruit stem rot. Severely infected fruits become completely rotten and desiccate. Tissues were excised from diseased sponge gourd fruits (sampled from Fongyuan, located at 24.25°N, 120.72°E in Taichung County), immersed in a solution containing 3% sodium hypochlorite and 70% ethanol for 1 min, washed three times with sterile water, and then cultured on potato dextrose agar (PDA) medium. A fungus, identified as Botrytis cinerea, produced abundant mycelium on PDA medium when incubated under constant fluorescent light 185 ± 35 μE·m^-2·s^-1 at 24°C. The conidia were smooth, hyaline, and globoid or slightly ellipsoid. The conidia measured 9.5 to 19.3 μm (average 13.8 μm) long and 6.0 to 17.8 μm (average 10.1 μm) wide, dimensions that are similar to the descriptions of B. cinerea (11 × 11 to 15 μm) that causes gray mold of strawberry (2). The identity of B. cinerea was also confirmed by the production of numerous black sclerotia on PDA plates incubated either in the dark or under light at 20 to 24°C for 9 to 10 days. Koch's postulates were fulfilled by using 3-day-old mycelial agar discs of the fungus or a spore suspension containing 10⁵ conidia per milliliter of distilled water as inoculum. Shallow (2 × 2 × 2 mm) incisions were made on fresh sponge gourd fruits with a sterile scalpel and inoculated with either a 5-mm mycelial disc or 0.5 ml of the spore suspension. Inoculated areas were covered with moist sterile cotton, and the fruits were enclosed in a plastic bag and incubated at 20 to 24°C for 3 days. Wounded fruits inoculated with PDA discs or sterile distilled water alone served as controls. Pathogenicity tests were performed three times using five fruits in each trial. Symptoms and signs of the disease similar to those described above were observed in all (100%) the inoculated fruits, while no symptoms developed in the control fruits. Reisolation from the inoculated fruits consistently yielded B. cinerea. Reciprocal inoculations on sponge gourd, guava, and strawberry with mycelial discs or spore suspensions of a B. cinerea isolate obtained from sponge gourd, guava, and strawberry showed cross pathogenicity among isolates and hosts. Important groups of plants that are attacked by B. cinerea are vegetables, small berry fruits, ornamentals, and bulbs (1). Though 80 species of host plants, mostly shrubs and nursery plants, were reported to be the host of B. cinerea in Taiwan (3), to our knowledge, this is the first report of gray mold disease affecting sponge gourd in Taiwan. References: (1) G. N. Agrios. Plant Pathology. Academic Press. San Diego, 2005. (2) J. L. Mass, ed. Page 56 in: Compendium of Strawberry Diseases. The American Phytopathological Society. St. Paul, MN, 1984. (3). Y. Ko et al. Plant Prot. Bull. (Taiwan) 37:439, 1995.

Are the local blood oxygen level-dependent (BOLD) signals caused by neural stimulation response dependent on global BOLD signals induced by hypercapnia in the functional MR imaging experiment? Experiments of long-duration hypercapnia and multilevel carbon dioxide concentration

BACKGROUND AND PURPOSE

The relationship between the local blood oxygen level-dependent (BOLD) signals caused by neural stimulation (fBOLD) and the global BOLD signals induced by hypercapnia (hBOLD) has not been fully investigated. In this study, we examine whether fBOLD is modulated by hBOLD signals, by means of experiments using a relatively wide range of inhaled carbon dioxide (CO(2)) for a long duration of 5 minutes.

MATERIALS AND METHODS

Ten healthy volunteers were recruited, each undergoing 6 separate experiments by inhaling gas mixtures with different fractions of CO(2) (room air, 3%-7%). Each experiment contained 3 phases, prehypercapnic, hypercapnic, and posthypercapnic, during which boxcar visual stimulus was given. The local fBOLD signals were measured from areas showing activation patterns highly correlated with the visual stimulus paradigm, whereas the global hBOLD signals were measured from areas showing no visual activations. Percentage changes in fBOLD during transient-state hypercapnia and steady-state hypercapnia were both investigated in response to varying degrees of hypercapnic perturbations.

RESULTS

The hBOLD signals increased with increase of inhaled CO(2) fractions. The duration for the hBOLD signals to reach steady state prolonged with increase of inhaled CO(2) fractions. Normalized fBOLD ratio was inversely related to the inhaled CO(2) during steady-state hypercapnia but showed positive association with hBOLD during transient-state hypercapnia.

CONCLUSION

Our study concludes that the steady-state fBOLD signal intensity is dependent on and inversely related to the hBOLD signals. Previous reports documenting independent and additive relationships between hBOLD and fBOLD may likely be due to transient-state observations.

Application of immobilized cells to the treatment of cyanide wastewater

Cyanide is highly toxic to living organisms, particularly in inactivating the respiration system by tightly binding to terminal oxidase. To protect the environment and water bodies, wastewater containing cyanide must be treated before discharging into the environment. Biological treatment is a cost-effective and environmentally acceptable method for cyanide removal compared with the other techniques currently in use. Klebsiella oxytoca (K. oxytoca), isolated from cyanide-containing industrial wastewater, has been shown to be able to biodegrade cyanide to non-toxic end products. The technology of immobilized cells can be applied in biological treatment to enhance the efficiency and effectiveness of biodegradation. In this study, potassium cyanide (KCN) was used as the target compound and both alginate (AL) and cellulose triacetate (CTA) techniques were applied for the preparation of immobilized cells. Results from this study show that KCN can be utilized as the sole nitrogen source by K. oxytoca. The free suspension systems reveal that the cell viability was highly affected by initial KCN concentration, pH, and temperature. Results show that immobilized cell systems could tolerate a higher level of KCN concentration and wider ranges of pH and temperature, especially in the system with CTA gel beads. Results show that a longer incubation period was required for KCN degradation using immobilized cells compared to the free suspended systems. This might be due to internal mass transfer limitations. Results also indicate that immobilized systems can support a higher biomass concentration. Complete KCN degradation was observed after the operation of four consecutive degradation experiments with the same batch of immobilized cells. This suggests that the activity of the immobilized cells can be maintained and KCN can be used as the nitrogen source throughout KCN degradation experiments. Results reveal that the application of immobilized cells of K. oxytoca is advantageous to the maintenance of KCN degradation efficiency. Thus, it is conceivable that the immobilized cells of K. oxytoca would be applicable to the treatment of cyanide-containing wastewaters.

Heterogeneous catalytic oxidation of hypophosphite by H2O2: pH effect

Phosphorus chemicals control key aspects of eutrophication and other environmental process. Hypophosphite (HP) originating from manmade and natural sources was evidenced as present in the environment and was investigated rarely. Recently, iron oxide has been used as a catalyst for oxidising organic contaminants with hydrogen peroxide (i.e. heterogeneous Fenton-like reaction). This study focused mainly on the oxidation of 1.0 mM HP by hydrogen peroxide in the presence of a novel iron oxide catalyst (B1 catalyst) which was prepared through a fluidised-bed Fenton reactor (FBR-Fenton). The background experiments including the oxidation experiment of HP by air only, by H2O2 only and adsorption of HP by B1 catalyst were first elucidated. It was found that HP could not be oxidised at all by air and H2O2 at pH 2.5-12 in 24 hours. On the other hand, it could be adsorbed by B1 catalyst with 89.8% removal at pH 2.5 in 5 hours and complete desorption at pH 11.0. Then, we investigated the effects of pH and Fe leaching from the catalyst on the oxidative efficiency of HP. We found that although the removal rate of HP at pH 2.5 is faster than that at pH 4.0, B1 catalyst has a higher HP oxidation efficiency at pH 4.0 than that at pH 2.5. We conclude that it is a major heterogeneous catalytic oxidation by our novel iron oxide catalyst to oxidise HP at pH 4.0. Also, B1 could be a useful and potential catalyst for the treatment of HP wastewater.

Molecular orientation and alignment of rubbed poly(vinyl cinnamate) surfaces

We observed that weakly and strongly rubbed polyvinyl-cinnamate surfaces align liquid crystal films perpendicular and parallel to the rubbing direction, respectively. Surface-specific sum-frequency vibrational spectroscopy was used to probe molecular orientations and alignments of the rubbed surfaces and provide a molecular-level understanding of the observation.

Oncoplastic breast conserving surgery: a renaissance of anatomically-based surgical technique

Using oncoplastic surgical techniques for breast preservation, breast surgeons can achieve widened surgical margins at the same time that the shape and appearance of the breast is preserved and sometimes rejuvenated. Oncoplastic surgical resection is designed to follow the cancer's contour, which generally follows the segmental anatomy of the breast, which has been well understood since the mid 19th century because of pioneering anatomic studies performed by Sir Astley Paston Cooper. The quadrantectomy, developed by Veronesi and colleagues in the 1970's, follows these same anatomic principles of wide segmental resection. The more surgically narrow lumpectomy as popularized in the U.S. uses a smaller, scoop-like non-anatomic resection of cancer. With negative surgical margins, the lumpectomy is equivalent to the quadrantectomy in achieving the goals of breast conservation as measured by local recurrence and survival. However, the lumpectomy is less versatile for resection of larger cancers, and can be more prone to creating suboptimal cosmetic defects. Cancers with large in situ components can be particularly problematic for resection with the standard lumpectomy, when they extend both centrally toward the nipple and peripherally to distal terminal ductulo-lobular units, which typically occur in a pie-shaped segmental distribution. Ductal segments, each of which ultimately drains to a single major lactiferous sinus at the nipple, vary in size and depth in the breast. Breast surgeons should carefully evaluate the cancer distribution and extent in the breast before operation. A combination of imaging methods (mammography with magnification views, ultrasonography, magnetic resonance imaging [MRI], or all) may yield the best estimates of overall tumor extent. Multiple bracketing wires afford the greater help to complete surgical excision. Those tumors with segmental spreading are best excised by oncoplastic resections according to their distribution.

Posterior epidural migration of a sequestrated lumbar disk fragment: MR imaging findings

We present a 75-year-old man who, for 2 weeks, had progressive pain in both of his thighs when standing straight. MR imaging showed a sequestrated disk fragment, which had a signal intensity similar to that of a herniated disk with a rim enhancement in the posterior epidural space and a ruptured outermost annulus of the intervertebral disk at L2-3. Awareness of these MR imaging findings can help in the diagnosis of posterior epidural disk migration.

Optical properties and carrier dynamics of self-assembled GaN/Al(0.11)Ga(0.89)N quantum dots

GaN quantum dots were grown on an Al(0.11)Ga(0.89)N buffer layer by using flow rate modulation epitaxy. The Stranski-Krastanov growth mode was identified by an atomic force microscopy study. The thickness of the wetting layer is about 7.2 monolayers. The temperature dependent photoluminescence studies showed that at low temperature the localization energy, which accounts for de-trapping of excitons, decreases with the reducing dot size. The decrease in emission efficiency at high temperature is attributed to the activation of carriers from the GaN dot to the nitrogen vacancy (V(N)) state of the Al(0.11)Ga(0.89)N barrier layer. The activation energy decreases with reducing dot size.

First Report of Southern blight of Formosan Michelia Seedlings in Taiwan

Formosan michelia (Michelia compressa (Maxim.) Sargent) is a native, giant evergreen tree in Taiwan. This species is used for afforestation, provision of shade in domestic situations, used in parks, and also for furniture. During the summer of 2004, a sudden wilt of 1-year-old plants was observed in a nursery of northern Taiwan. Initial symptoms included stem necrosis at the soil line, yellowing, and tan discoloration of leaves. As stem necrosis progressed, infected plants wilted and died. Necrotic tissues were covered with whitish mycelium that differentiated into reddish brown spherical (1 to 2 mm in diameter) sclerotia. Sclerotium rolfsii was consistently recovered from the surface of symptomatic stem sections that were disinfected for 1 min in 0.5% NaOCl and then plated on potato-dextrose agar amended with 100 ppm ampicillin. Pathogenicity of two S. rolfsii isolates was confirmed by inoculating 1-year-old Formosan michelia seedlings grown in pots. Inoculum consisted of mycelium and sclerotia of the pathogen placed on the soil surface around the base of each plant. Noninoculated plants served as controls. All plants were kept in a growth chamber at 25 to 35°C with relative humidity >95%. Inoculated plants developed symptoms within 14 days while control plants remained symptomless. Sclerotia developed on infected tissues, and S. rolfsii was reisolated from symptomatic tissues. This disease has been observed on many species of plants (1), but to our knowledge, this is the first report of southern blight of Formosan michelia seedlings caused by S. rolfsii in Taiwan. Reference: (1) Y. P. Tsai, ed. List of Plant Diseases in Taiwan. The Plant Protection Society of the Republic of China and The Phytopathological Society of the Republic of China, 1991.

Modelling the effect of caveolae on G-protein activation

In this paper, we study the effects on G-protein activation of a non-uniform distribution of signalling components. The spatial heterogeneity is attributed to caveolae, a specific membrane microdomain which has been observed to redistribute and concentrate signalling molecules. Diffusive coagulation-fragmentation equations are used to describe the aggregation of caveolin homo-oligomers and the subsequent formation of caveolae. A system of reaction-diffusion equation is thus formulated and, in order to describe the restrictions imposed by caveolae on the movement of receptors and G-protein, a segregation coefficient is introduced which serves to regulate the preference of the species to segregate according to the concentration of caveolae. The results demonstrate that the heterogeneous distribution of the signalling components and the efficiency of G-protein activation can vary significantly, depending on the concentration of caveolae.

InGaN self-assembled quantum dots grown by metal-organic chemical vapour deposition with growth interruption

Self-assembled InGaN quantum dots (QDs) were grown by metal-organic chemical vapour deposition with growth interruption at low V/III ratio and low growth temperature on sapphire substrates. The effects of the interruption time on the morphological and optical properties of InGaN QDs were studied. The results show that the growth interruption can modify the dimension and distribution of InGaN QDs, and cause the QD emission wavelength to blue shift with increasing interruption time. A density of InGaN QDs of about 4.5 × 10(10) cm(-2) with an average lateral size of 11.5 nm and an average height of 1.6 nm can be obtained by using a growth interruption time of 60 s.

Novel activated alumina-supported iron oxide-composite as a heterogeneous catalyst for photooxidative degradation of reactive black 5

A novel activated alumina-supported iron oxide-composite (denoted as FeAA-500) was prepared by so-called fluidized-bed reactor (FBR) crystallization. X-ray powder diffraction (XRD), N2 adsorption/desorption, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) were used to characterize the FeAA-500. The photo-catalytic activity of the FeAA-500 was evaluated in the photooxidative degradation of 0.1 mM azo-dye reactive black 5 (RB5) in the presence of H2O2 and UVA light (lambda = 365 nm) in a solution with a pH of 2.5. Complete decolorization of the model pollutant RB5 was achieved; the total organic carbon (TOC) removal ratio was 95%, and a trace amount of leached ferric ion was detected following 75 min of reaction when 2.0 g/L FeAA-500 was used as a catalyst. FeAA-500 has high photo-catalytic activity; it is therefore a promising heterogeneous photocatalysis of the degradation of organic compounds.