Can a "Pandemic Life Adaptation" Digital Technology Curriculum Reduce the Digital Disadvantage of Older Adults During COVID-19? An Intervention Study from Shanghai.

Older adults are at a digital disadvantage because of social stereotypes and a lack of social support; however, smartphones have become a necessary technology to cope with crises and daily life in China, especially during the pandemic. This study aimed to help marginalized older adults take on new tasks by developing digital technology education that used a framework of social cognitive theory in social work. The study followed a quasi-experimental design in which 153 elderly people were recruited from three community service centers; 90 of the participants received 6-weekly intervention. Intent-to-treat analysis, effect size calculations, and sensitivity analysis were conducted. The findings show that digital education significantly enhanced two domains of digital life adaptation abilities: general digital life adaptation abilities [g = .50, 95% CI (.70, 2.69)] and pandemic digital life adaptation abilities [g = .89, 95% CI (.96, 2.07)]. The intervention also improved three domains of digital self-efficacy: sharing and communication [g = .55, 95% CI (.04, .48)], verification [g = .34, 95% CI (.01, .59)], and influencing others [g = .53, 95% CI (.13, .77)]. The study showed that the new intervention approach reduced the harm to vulnerable older adults in the digital wave, especially during the pandemic.

Advancing High-Throughput MS-Based Protein Quantification: A Case Study on Quantifying 10 Major Food Allergens by LC-MS/MS Using a One-Sample Multipoint External Calibration Curve.

The LC-MS-based method has emerged as the preferred approach for quantifying food allergens. However, the preparation of a traditional calibration curve (MSCC) is labor-intensive and error-prone. Here, a sensitive and robust LC-MS/MS method for quantifying 10 major food allergens was developed and validated, where the one-sample multipoint external calibration curve (OSCC) was employed instead of MSCC. By employing the multiple isotopologue reaction monitoring (MIRM) technique with only one spiked level in the blank, OSCC can be effectively established. Results demonstrate that the proposed method exhibits excellent performance in selectivity, sensitivity, accuracy, and precision, comparable to that of the traditional MSCC. Additionally, this strategy allows for isotope sample dilution by monitoring the less abundant MIRM channel. Moreover, the developed method was successfully applied to investigate the contamination of 10 food allergens in commercial food products. With its high throughput and robustness, the MIRM-OSCC-LC-MS/MS methodology has many potential applications, especially in the MS-based protein quantification analysis.

An integrated calibration strategy for the development and validation of an LC-MS/MS method for accurate quantification of egg allergens (Gal d 1-6) in foods.

Accurate determination of egg allergens in food is vital for allergen management and labeling. However, quantifying egg allergens with mass spectrometry poses challenges and lacks validation methods. Here, we developed and validated an LC-MS/MS method for quantifying egg allergens (Gal d 1-6) in foods. Sample extraction, enzymatic digestion, purification, proteins/peptides selection, and calibration curves were optimized. VMVLC[+57]NR (Gal d 1) and GTDVQAWIR (Gal d 5) exhibited outstanding sensitivity and stability, serving as quantitation markers for egg white and yolk. Using a matrix-matched calibration curve with allergen ingredients as calibrants and labeled peptides as standards, we achieved highly accurate quantitation. Validation involved spiking egg protein into egg-free foods, showing excellent sensitivity (LOQ: 1-5 mg/kg), accuracy (62.4 %-88.5 %), and reproducibility (intra-/inter-day precision: 3.5 %-14.2 %/8.2 %-14.6 %). Additionally, we successfully applied this method to commercial food analysis. These findings demonstrate optimal allergen selection, peptides, and calibration strategy are crucial parameters for food allergen quantification via MS-based methods.

Unraveling Multiple Pathways of Electron Donation from Phenolic Moieties in Natural Organic Matter.

Natural organic matter (NOM) exhibits a distinctive electron-donating capacity (EDC) that serves a pivotal role in the redox reactions of contaminants and minerals through the transformation of electron-donating phenolic moieties. However, the ambiguity of the molecular transformation pathways (MTPs) that engender the EDC during NOM oxidation remains a significant issue. Here, MTPs that contribute to EDC were investigated by identifying the oxidized products of phenolic model compounds and NOM samples in direct or mediated electrochemical oxidation (DEO or MEO, respectively) using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). It was found that the oxidation of newly formed phenolic-OH (ArOH) and the oxidative coupling reaction of the phenoxy radical are the main MTPs that directly contribute to EDC, in addition to the transformation of hydroquinones to quinones. Notably, the oxidative coupling reaction of ArOH contributed at least 22-42% to the EDC. Ferulic acid-like structures can also directly contribute to EDC by incorporating H2O into their acrylic substituents. Furthermore, the opening of C rings can indirectly attenuate the EDC through structural alterations in the electron-donating process of NOM. Decarboxylation can either weaken or enhance the EDC depending on the structure of the phenolic moieties in NOM. These findings suggest that the EDC of NOM is a comprehensive result of multiple NOM MTPs, involving not only ArOH oxidation but also the addition of H2O to olefinic bonds and bond-breaking reactions. Our work provides molecular evidence that aids in the comprehension of the multiple EDC-associated transformation pathways of NOM.

Using the end-member mixing model to evaluate biogeochemical reactivities of dissolved organic matter (DOM): autochthonous versus allochthonous origins.

Dissolved organic matter (DOM) is an essential component of environmental systems. It usually originates from two end-members, including allochthonous and autochthonous sources. Previously, links have been established between DOM origins/sources and its biogeochemical reactivities. However, the influence of changes in DOM characteristics driven by end-member mixing on DOM biogeochemical reactivities has not been clarified. In this study, we investigated variations of DOM reactivities responding to the dynamics of DOM characteristics induced by different mixing ratios of two DOM end-members derived from humic acid (HA) and algae, respectively. Four biogeochemical reactivities of DOM were evaluated, including biodegradation, ·OH production, photodegradation, and redox capacity. Results showed that the variations of DOM characteristics due to the two end-members mixing significantly impact its biogeochemical reactivities. However, not all spectral parameters and reactivities followed the conservative mixing behavior. In contrast to reactivities of ·OH production and redox capacity, mixed samples showed apparent deviations from conservative linear relationships in biodegradation and photodegradation due to the interaction between the two end-members. Regarding the role of DOM properties influencing reactivity changes, peak A and M were recognized as the most stable parameters. However, peak C and SUVA254 were identified as the most vital contributors for explaining DOM reactivity variations. These findings suggest that a general model for describing the dynamic relationship between DOM source and reactivity cannot be proposed. Thus, the dynamics of DOM reactivity in diverse ecosystems cannot be estimated simply by the "plus or minus" of the reactivity from individual end-member. The effect of end-member mixing should be evaluated in a given reactivity instead of generalization. This study provides important insights for further understanding the dynamics of DOM's environmental role in different ecosystems influenced by variations of source inputs. In future, more field investigations are needed to further verify our findings in this study, especially in the scenario of end-member mixing.

Effects of biochar on the degradation of organophosphate esters in sewage sludge aerobic composting.

In this study, the impact of biochar on the degradation of organophosphate esters (OPEs) during the aerobic composting of sewage sludge was investigated. Three treatments were conducted with different percentages of biochar in the compost, including 5 %, 10 %, and 20 %. The treatment with 10 % of biochar showed the longest thermophilic phase compared to that of 5 % and 20 % of biochar, which greatly promoted the decomposition of organic matter. In addition, the degradation rate of the hard-to-degrade chlorinated-OPEs was significantly increased by 10 % biochar, reaching to 57.2 %. Correspondingly, approximately 43.6 % of the total concentration of OPEs (Σ6OPEs) was eliminated in the presence of 10 % of biochar, which was higher than the treatments with 5 % and 20 % of biochar. Biochar significantly influenced the microbial community structure of compost, but the previously reported organophosphorus-degrading bacteria did not play a major role in the degradation of OPEs. The redox ability of the increased oxygen-containing functional groups such as quinone on the surface of biochar and the biochar-mediated electron transfer ability may play an essential role in the degradation of OPEs during the composting process.

Loss and Increase of the Electron Exchange Capacity of Natural Organic Matter during Its Reduction and Reoxidation: The Role of Quinone and Nonquinone Moieties.

Redox-active quinone and nonquinone moieties represent the electron exchange capacity (EEC) of natural organic matter (NOM), playing an important role in the electron transfer link of microbes and transformation of contaminants/metal minerals. However, the corresponding transformation of quinone/phenol and their respective influence on the EECs during reduction and reoxidation remain poorly characterized. Besides, it is still controversial whether nonquinones donate or accept electrons. Herein, we demonstrated that reoxidation of NOM after reduction can form new phenolic/quinone moieties, thus increasing the EEC. The assessment for the EEC, including the electron-donating capacity (EDC) and electron-accepting capacity (EAC), of nonquinones reflects the contribution of sulfur-containing moieties with considerable EDCs and EACs. In contrast, nitrogen-containing moieties donate negligible electrons even at Eh = +0.73 V. The contributions of both thiol and amine moieties to the EEC are greatly affected by adjacent functional groups. Meanwhile, aldehydes/ketones did not display an EAC during the electron transfer process of NOM. Furthermore, substantially increased EDC at Eh from +0.61 to +0.73 V could not be fully explained using thiol and phenolic moieties, suggesting the contribution of unknown moieties with high oxidation potential. The overall findings suggest that the roles of new quinones/phenol (derived from the addition of oxygen to condensed aromatic/lignin-like components) during redox dynamic cycling and thiol species should be considered in assessing the electron transfer processes of NOM.

Occurrence and Estrogenic Potency of Bisphenol Analogs in Sewage Sludge from Wastewater Treatment Plants in Central China.

Land application is suggested to be the most economical sludge disposal method but is also a potential source of bisphenol analogs (BPs) to the environment. In this study, BP concentrations in sewage sludge from Henan province ranged from 15.1 to 2237 ng g-1 dw. BPA was dominant with mean concentration of 140 ng g-1 dw, followed by BPS (mean 43.4 ng g-1 dw), BPF (mean 7.98 ng g-1 dw), BPAF (mean 1.04 ng g-1 dw), BPAP (mean 0.88 ng g-1 dw), BPB (mean 0.38 ng g-1 dw), and BPZ (mean 0.33 ng g-1 dw). Apart from BPB, no significant correlations were found between BPs and wastewater treatment plants characteristics, probably because adsorption does not play a major role in the removal of BPs. The estimated total emission flux of BPs from sludge-amended soils are approximately 62.7 kg year-1. BPA is the largest contributor with emission flux of 45.3 kg year-1. Hazard quotient values for BPs in sludge-amended soils are 3-6 orders of magnitude lower than 1 with total 17ß-estradiol equivalents ranging from 0.33 to 26.8 pg g-1 E2EQ dw. Overall, although being partially replaced by other analogs, BPA is still widely used in Henan province.

Determination of freely dissolved polycyclic aromatic hydrocarbons in human serum using core-shell Fe3O4@polyacrylate magnetic microspheres by exclusive volume effect.

Freely dissolved concentration is an important parameter for evaluating the bioavailability of compounds. Negligible-depletion solid-phase microextraction (nd-SPME) has been widely used for the determination of freely dissolved compounds but suffered from long equilibrium time. Multifunctional mesoporous composite microspheres have large specific surface area and therefore extraction equilibrium could be reached in a short time. In this study, a novel method was developed for quick determination of freely dissolved polycyclic aromatic hydrocarbons (PAHs) in human serum using core-shell polyacrylate-ferriferous oxide magnetic microspheres (Fe3O4@PA). Mass transfer of PAHs from sample solution to Fe3O4@PA was greatly increased owing to unique properties including large surface area (58.5 m2 g-1), high pore volume (0.10 cm3 g-1) and thin coating layer (50 nm). Freely dissolved PAHs can be selectively extracted because of the mesoporous structure of PA coating layer with uniform pore size of 7.08 nm. However, bound forms of PAHs would not be able to access into pore channels due to size exclusion. In comparison with long equilibration time (139 h) by nd-SPME, equilibrium can be reached within 29 min (t90%) using Fe3O4@PA as novel sorbents. The sorption coefficients (log KBSA) of PAHs to bull serum albumin (BSA) ranged from 3.36 to 4.87, which are consistent with the values measured by nd-SPME (log KBSA = 3.64-5.12). Finally, the freely dissolved PAHs (Cfree) measured by the proposed method (0.69-1.92 µg L-1) have a good agreement with that by nd-SPME (0.56-2.11 µg L-1), indicating that it is feasible for rapid determination of free forms of compounds in real samples by Fe3O4@PA.

Degradation of organophosphate esters in sewage sludge: Effects of aerobic/anaerobic treatments and bacterial community compositions.

This dataset provides detail information on the analytical methods of organophosphate esters (OPEs) in sludge samples, including the sample preparation, ultra-high performance liquid chromatography-tandem mass spectrometric (UPLC-MS/MS) analysis, quality assurance and quality control (QA/QC). The concentration of target OPE compounds in collected samples of four individual treatment was provided, including aerobic composting combined with pig manure (T1), aerobic composting without pig manure (T2), anaerobic digestion combined with pig manure (T3), and anaerobic digestion without pig manure (T4). To investigate the variation of bacterial community compositions, principal components analysis (PCA) was provided based on the high-throughput sequencing. These data would be useful for clarifying the removal of OPEs under aerobic and anaerobic conditions. Besides, it also provides important information on the potential bacterial strains responsible for the biodegradation of OPEs in each treatment.

Degradation of organophosphate esters in sewage sludge: Effects of aerobic/anaerobic treatments and bacterial community compositions.

In this study, the degradation of organophosphate esters (OPEs) in sewage sludge with aerobic composting and anaerobic digestion was investigated. The total concentrations of six OPEs (ΣOPEs) in the whole treatment process reduced in the order of anaerobic digestion combined with pig manure (T3) > aerobic composting combined with pig manure (T1) > aerobic composting (T2) > anaerobic digestion (T4). The addition of pig manure significantly enhanced the removal rate of OPEs in both aerobic and anaerobic treatments. The abundance and diversity of bacterial community reduced after the treatment process. Shannon index, principal component analysis, network analysis, and heat map further confirmed the variation of bacterial community compositions among different treatments. Five genera (i.e., Flavobacterium, Bacillus, Alcaligene, Pseudomonas, and Bacillus megaterium) might be responsible for the degradation of OPE compounds in sewage sludge.

Application of Fe3O4@MIL-100 (Fe) core-shell magnetic microspheres for evaluating the sorption of organophosphate esters to dissolved organic matter (DOM).

Organophosphate esters (OPEs) are widely used as flame retardants and plasticizers in many products and materials. Because of the potential biologic toxicity on human beings, OPEs are regarded as a class of emerging pollutants. Dissolved organic matters (DOM) have significant effects on the bioavailability and toxicity of the pollutants in the environment. Negligible-depletion solid-phase microextraction (nd-SPME) is an efficient way for measuring the freely dissolved pollutants but suffers from long equilibrium time. Metal-organic frameworks (MOFs) are a class of porous crystalline materials with unique properties such as high pore volume, regular porosity, and tunable pore size, being widely used for the extraction of various organic compounds. Here we developed a novel method for quick determination the sorption coefficients of OPEs to DOM in aquatic phase using Fe3O4@MIL-100 (Fe) core-shell magnetic microspheres. The mesoporous structures of the as-synthesized microspheres hindered the extraction of OPEs which associated with humic acid due to the volume exclusion effect. However, the freely dissolved OPEs can access into the mesoporous and then were extracted by MIL-100 (Fe). Due to the small pore size (4.81 nm), large surface area (141 m2 g-1), high pore volume (0.17 g3 g-1), and ultra-thin MOFs layers, Fe3O4@MIL-100 (Fe) core-shell magnetic microspheres have large contact area for the analytes in aqueous phase and therefore the diffusion distance was largely shortened. Besides, the microspheres can be collected conveniently after the extraction process by applying a magnetic field. Compared to the nd-SPME method with 35 h equilibration time (t90%), the proposed method for these studied OPEs only need 24 min to achieve equilibration. The sorption coefficients (logKDOC) of the OPEs to humic acid were ranged from 3.84-5.28, which were highly consistent with the results by using polyacrylate-coated fiber and polydimethylsiloxane-coated fiber with nd-SPME.

Bis(trifluoromethylsulfonyl)imide-based frozen ionic liquid for the hollow-fiber solid-phase microextraction of dichlorodiphenyltrichloroethane and its main metabolites.

1-Hexadecyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide is a solid-phase ionic organic material under ambient temperature and is considered as a kind of "frozen" ionic liquid. Because of their solid-state and ultra-hydrophobicity, "frozen" ionic liquids are able to be confined in the pores of hollow fiber, based on which a simple method was developed for the hollow-fiber solid-phase microextraction of dichlorodiphenyltrichloroethane and its main metabolites. Under optimized conditions, the proposed method results in good linearity (R2 > 0.9965) over the range of 0.5-50 µg/L, with low limits of detection and quantification in the range of 0.33-0.38 and 1.00-1.25 µg/L, respectively. Intra- and interday precisions evaluated by relative standard deviation were 3-6 and 1-6%, respectively. The spiked recoveries of dichlorodiphenyltrichloroethane and its main metabolites from real water samples were in the range of 64-113 and 79-112%, respectively, at two different concentration levels. The results suggest that "frozen" ionic liquids are promising for use as a class of novel sorbents.

Trace determination of organophosphate esters in white wine, red wine, and beer samples using dispersive liquid-liquid microextraction combined with ultra-high-performance liquid chromatography-tandem mass spectrometry.

In this study, dispersive liquid-liquid microextraction coupled with ultra-high-performance liquid chromatography-tandem mass spectrometry was developed for the analysis of five representative organophosphate esters (OPEs) in wine samples. Under optimized conditions, the proposed method resulted in good linearity (R2>0.9933) over the range of 0.1-100µgL-1, with limits of detection (LODs, S/N =3) and quantification (LOQs, S/N =10) in the ranges of 0.48-18.8ngL-1 and 1.58-62.5ngL-1, respectively. Inter- and intra-assay precisions of RSD% ranged from 3.21% to 6.13% and from 1.69% to 7.63%, respectively. The spiked recoveries of target OPEs from white wine, red wine, and beer samples were in the ranges of 80-122%, 76-120%, and 76-110%, respectively, at two different concentration levels. The total concentrations of five OPEs found in white wine, red wine, and beer samples were in the ranges of 0.29-0.85µgL-1, 1.00-3.05µgL-1, and 0.86-1.47µgL-1, respectively.

Accelerated solvent extraction combined with solid phase extraction for the determination of organophosphate esters from sewage sludge compost by UHPLC-MS/MS.

Organophosphate esters (OPEs), widely used as flame retardants and plasticizers, are regarded as emerging pollutants. OPEs are prone to concentrate into residual activated sludge, which might cause secondary pollution if not suitably treated. Composting is an economical and effective approach to make sewage sludge stable and harmless. Therefore, it is essential to develop a novel method for analyzing OPEs in sewage sludge compost samples. However, in the composting process, large amounts of amendments are doped into the sludge to adjust the carbon-nitrogen ratio. Amendment has a strong capacity for adsorption and thus induces a decrease of extraction efficiency. This study developed a novel procedure for determining OPEs in compost samples. Accelerated solvent extraction (ASE) and solid phase extraction (SPE) were used for extracting and concentrating the OPEs from sewage sludge compost samples, and then analyzed by UHPLC-MS/MS. Some parameters were optimized in this study, mainly including the extraction solvent type, extraction temperature, static extraction time, extraction cycles, and flush volume. Under the optimal conditions, the proposed method showed good linearity between 0.50 and 100 µg kg-1 with regression coefficients in the range of 0.9984-0.9998. Detection limits were in the range of 0.02-3 µg kg-1 with standard deviations ranging from 2 to 6%. Acceptable recoveries between 56 and 119% for samples spiked at different concentration levels were achieved. In contrast, the recoveries merely ranged from 24 to 58% by using ultrasonic-assisted extraction. Graphical abstract A comparison of recoveries between ultrasonic-assisted extraction (UAS) and accelerated solvent extraction (ASE) for organophosphate esters from sewage sludge compost samples.

Comparison of wastewater treatment processes on the removal efficiency of organophosphate esters.

Organophosphate esters (OPs), widely used as flame retardants and plasticizers, are regarded as a class of emerging pollutants. The effluent of municipal wastewater treatment plants is generally considered to be the main contributor of OP pollution to the surface water. In this study, anoxic-oxic (AO) and University of Capetown (UCT) processes were selected to investigate the removal efficiency of OPs. The results indicated that the UCT process showed better removal efficiency than that of the AO process. For the chlorinated OPs, approximately 12.3% of tri(2-chloroethyl)phosphate and 11.8% of tri(chloropropyl)phosphate can be removed in the UCT process, which was 12% and 7.8% higher than that of the AO process. In contrast, non-chlorinated OPs, including tris(2-butoxyethyal)phosphate, triphenyl phosphate, and tributyl phosphate, were able to be removed in both processes, with the removal rate of 85.1%, 74.9%, and 29.1% in the AO process, and 88.4%, 63.6%, and 25.2% in the UCT process. Furthermore, linear correlation between the removal rate and logKow of OPs (r2 = 0.539) was observed in the AO process, indicating that OPs with high Kow value (e.g. tri(dichloropropyl)phosphate and triphenyl phosphate) are prone to be removed by adsorption on the residual activated sludge.

The prevalence of mild cognitive impairment and its etiological subtypes in elderly Chinese.

BACKGROUND: Epidemiologic studies on mild cognitive impairment (MCI) are limited in China. METHODS: Using a multistage cluster sampling design, a total of 10,276 community residents (6096 urban, 4180 rural) aged 65 years or older were evaluated and diagnosed with normal cognition, MCI, or dementia. MCI was further categorized by imaging into MCI caused by prodromal Alzheimer's disease (MCI-A), MCI resulting from cerebrovascular disease (MCI-CVD), MCI with vascular risk factors (MCI-VRF), and MCI caused by other diseases (MCI-O). RESULTS: The prevalences of overall MCI, MCI-A, MCI-CVD, MCI-VRF, and MCI-O were 20.8% (95% confidence interval [CI] = 20.0-21.6%), 6.1% (95% CI = 5.7-6.6%), 3.8% (95% CI = 3.4-4.2%), 4.9% (95% CI = 4.5-5.4%), and 5.9% (95% CI = 5.5-6.4%) respectively. The rural population had a higher prevalence of overall MCI (23.4% vs 16.8%, P < .001). CONCLUSIONS: The prevalence of MCI in elderly Chinese is higher in rural than in urban areas. Vascular-related MCI (MCI-CVD and MCI-VRF) was most common.

The prevalence of dementia in urban and rural areas of China.

OBJECTIVE: The Chinese population has been aging rapidly and the country's economy has experienced exponential growth during the past three decades. The goal of this study was to estimate the changes in the prevalence of dementia, Alzheimer's disease (AD), and vascular dementia (VaD) among elderly Chinese individuals and to analyze differences between urban and rural areas. METHODS: For the years 2008 to 2009, we performed a population-based cross-sectional survey with a multistage cluster sampling design. Residents aged 65 years and older were drawn from 30 urban (n = 6096) and 45 rural (n = 4180) communities across China. Participants were assessed with a series of clinical examinations and neuropsychological measures. Dementia, AD, and VaD were diagnosed according to established criteria via standard diagnostic procedures. RESULTS: The prevalence of dementia, AD, and VaD among individuals aged 65 years and older were 5.14% (95% CI, 4.71-5.57), 3.21% (95% CI, 2.87-3.55), and 1.50% (95% CI, 1.26-1.74), respectively. The prevalence of dementia was significantly higher in rural areas than in urban ones (6.05% vs. 4.40%, P < .001). The same regional difference was also seen for AD (4.25% vs. 2.44%, P < .001) but not for VaD (1.28% vs. 1.61%, P = .166). The difference in AD was not evident when the sample was stratified by educational level. Moreover, the risk factors for AD and VaD differed for urban and rural populations. CONCLUSIONS: A notably higher prevalence of dementia and AD was found in rural areas than in urban ones, and education might be an important reason for the urban-rural differences.

[Relationship between three neuropsychological tests and cerebral glucose metabolism in Alzheimer's disease].

OBJECTIVE: To study the relationship between the scores of 3 neuropsychological scales: MMSE, extended scale of dementia (ESD) and Blessed dementia scale (BDS) and cerebral glucose metabolism in Alzheimer's disease (AD) indicated by positron emission tomography (PET). METHODS: Brain scanning was performed with SIEMENS ECAT 47 PET scanner among 21 AD patients, aged 60 - 83 (10 mild, 6 moderate, and 5 severe), and 15 healthy persons, aged 57 - 73. The ratio of mean radioactivity of cerebral lobe to that of cerebellum as semi-quantitative parameters was used to evaluate the cerebral glucose metabolism. Cognitive function was assessed by three neuropsycholigical scales: MMSE, ESD and BDS. RESULTS: The average MMSE score was 13.3 +/- 6.3 (range 2 - 25), the average ESD score was 120.5 +/- 54.8 (range 28 - 200), and the average BDS score was 4.7 +/- 3.1 (range 0.5 - 10) in the AD patients. The decreases of glucose metabolism in parietal, frontal and temporal lobes were significantly positively correlated with MMSE and ESD scores, and negatively correlated with BDS scores in AD patients (P < 0.05). The correlations between MMSE and ESD (r = 0.886), MMSE and BDS (r = -0.763), and ESD and BDS (r = -0.773) were significant in AD patients (all P < 0.01). Taking the ratio of radioactivity of cerebral lobe to that of cerebellum as an independent variable X, the MMSE, ESD and BDS scorsas dependent variable Y, three regression equations were established as follows: Y = 40.11 * X- 25.32, Y = 309.19 * X- 180.9, Y = 19.97 - 16.53 * X. The independent variable entering the three regression equations was always the ratio of radioactivity of left parietal lobe to that of cerebellum. The ratio of radioactivity of left parietal lobe to that of cerebellum was a significant predictor for cognitive dysfunction measured by MMSE, ESD and BDS in AD patients (P < 0.01). CONCLUSION: MMSE, ESD and BDS scores correlate well with impaired cerebral glucose metabolism in AD. The function of left parietal lobe may play an important role in the progress of the disease. MMSE, ESD and BDS are good measures for cognitive dysfunction.

Rapid and direct determination of iodide in seawater by electrostatic ion chromatography.

An electrostatic ion chromatographic (IC) method for rapid and direct determination of iodide in seawater is reported. Separation was achieved using a reversed-phase ODS packed column (250x4.6 mm I.D.) modified by coating with Zwittergent-3-14 micelles, with an eluent comprising an aqueous solution containing 0.2 mM NaClO4 and 0.3 mM Zwittergent-3-14 and using UV detection at 210 nm. Samples prepared by dissolving NaIO3, NaNO2, NaBr, NaBrO3, NaNO3, NaI, and NaSCN in artificial or real seawaters were analyzed using this IC system. Nitrite, iodate, bromide, bromate, and nitrate showed very little or no retention, while iodide and thiocyanate were well separated, being eluted within 6 and 16 min, respectively. The detection limit for iodide obtained by injecting 400 microL of sample was 0.011 microM (S/N = 3), and the precision values obtained by analyzing samples containing 0.1 or 0.3 microM iodide in real seawater samples were 2.3% RSD and 1.2% RSD, respectively. Direct determination of iodide in real seawater samples was possible using this proposed IC system.