The time-varying effects of geopolitical risk on mutual fund risk taking.

Based on a time-varying parameter vector autoregression model with stochastic volatility (TVP-VAR-SV), this paper investigates the dynamic effects of geopolitical risk on mutual fund risk taking in China across three-time horizons and at three selected time points. Overall, the impulse responses are time-varying and we find a negative effect of geopolitical risk on mutual fund risk taking until 2015, with the short-term effect being the most pronounced, suggesting that when professional investors such as mutual fund managers are faced with the stock valuation uncertainty due to a geopolitical shock, they choose to reduce market risk exposures. After 2015, the short-term effect begins to diminish and gradually turns positive, which could be explained by the fact that with the increasing abundance and diversification of investment instruments, fund managers have more effective investment tools and more sophisticated trading strategies to hedge against geopolitical risk, rather than reducing market risk exposure. Further, we explore the heterogeneous effects of eight types of geopolitical risk and three types of mutual fund. The results indicate that the effect of geopolitical actions is stronger than that of geopolitical threats, while the effect of narrow geopolitical risk is stronger than that of broad geopolitical risk. Moreover, we find that the response of the risk taking of growth funds to the geopolitical risk is weaker than that of balanced and income funds.

Enhanced Cr (VI) reduction and removal by Fe/Mn oxide biochar composites under acidic simulated wastewater.

Chromium (Cr (VI)) can cause severe damage to the ecosystem and humans because of its toxicity. In this paper, the adsorbed Fe/Mn ions Bacillus cereus ZNT-03, lotus seeds, and graphene oxide were co-cultured as the raw materials. Fe/Mn oxide biochar composite (FMBC) was prepared to treat Cr (VI) by one-step pyrolysis. FMBC has high-density micropores, and the average pore size is about 0.82 nm. Fe (II), Mn (II), and N-containing functional groups could serve as electron donors for Cr (VI) reduction. The removal of Cr (VI) is monolayer chemisorption and pH-dependent. The maximum adsorption capacity of FMBC is 21.25 mg g-1. Cr (VI) is reduced and adsorbed on FMBC by physical adsorption, reduction, complexation, electrostatic attraction, and coprecipitation. The contribution ratio of the reduction mechanism to Cr (VI) is 72.25%. The packed column and regeneration experiments indicated that FMBC had excellent adsorption stability even after soaking in acidic simulated wastewater after 180 days (pH 1.5). These results indicate that FMBC can provide rapid reduction and efficient adsorption for Cr (VI), making it possible to apply in water treatment.

Bioactivity-Guided Separation of Anti-Cholinesterase Alkaloids from Uncaria rhynchophlly (Miq.) Miq. Ex Havil Based on HSCCC Coupled with Molecular Docking.

As an important source of cholinesterase inhibitors, alkaloids in natural products have high potential value in terms of exerting pharmacological activities. In this study, a strategy for targeted preparation of cholinesterase inhibitors in Uncaria rhynchophlly (Miq.) Miq. ex Havil (UR) by high-speed counter-current chromatography was provided. In the method, a two-phase polar solvent system composed of ethyl acetate/n-butanol/water (1:4:5, v/v/v) was used, which isolated five alkaloids from the UR extract for the first time. All alkaloids were identified by HR-ESI-MS and NMR as 7-epi-javaniside (1), vincosamide (2), strictosamide (3), cadambine (4), and 3α-dihydrocadambine (5). The poorly resolved compounds 2 and 3 were separated by preparative HPLC (prep-HPLC). Among them, compounds 1, 4, and 5 were firstly obtained from UR. The purity of these plant isolates was 98.8%, 98.7%, 99.2%, 95.7%, and 98.5%, respectively. Compounds 1-5 exhibited an inhibitory effect on acetyl-cholinesterase and butyryl-cholinesterase with an IC50 from 1.47 to 23.24 µg/mL and 1.01 to 18.24 µg/mL. Molecular docking and inhibitory activities indicated that compound 1 showed stronger inhibitory activity on acetyl-cholinesterase and butyryl-cholinesterase.

Bioactive polyacetylenes from Bidens pilosa L and their anti-inflammatory activity.

A new polyacetylenic glucoside together with three known compounds were isolated from the whole herb of Bidens pilosa L. The structure elucidation of these four compounds was employed by combining NMR and HR-MS data as 4-O-ß-D-glucopyranosyloxy-1-hydroxy- 6-(E)-tetradecene-8,10,12-triyne (1), 3-O-ß-D-glucopyranosyloxy-1-hydroxy-6-(E)-tetradec- ene-8,10,12-triyne (2), 2-O-ß-D-glucopyranosyloxy-1-hydroxy-5-(E)-tetradecene-7,9,11-triy- ne (3) and icthyothereol acetate (4). Additionally, bioactivity study showed that these compounds have potential anti-inflammatory activity. This study has certain guiding significance for the development and utilisation of polyacetylene compounds in Bidens pilosa L.

Rapid Separation and Efficient Removal of Cd Based on Enhancing Surface Precipitation by Carbonate-Modified Biochar.

The high buoyancy of biochar makes its application difficult in Cd removal. In this paper, the content of minerals was increased by modifying carbonate on the biochar surface using the vacuum impregnation method. Enhancing surface precipitation between minerals and Cd introduced a correspondingly great number of Cd precipitates on the biochar surface, leading to the rapid precipitation and separation of buoyant biochar. The physical and chemical properties of carbonate-modified biochar and the adsorption mechanism of Cd were comprehensively studied by jar tests, scanning electron microscopy-energy-dispersive X-ray spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The results showed that the adsorption of Cd by carbonate-modified biochar was controlled by multiple mechanisms, including surface precipitation, surface complexation, and Cd-π interaction. Surface precipitation dominated the removal of Cd. The contributions of Cd removal mechanisms indicated that the contribution proportions of minerals increased from 89.73 to 97.9% when the pyrolysis temperature increased from 300 to 600 °C, while the contribution proportions of Cd-π binding decreased from 9.99 to 2.08%. Meanwhile, oxygen functional groups have only a marginal effect on Cd adsorption. Besides, the results revealed that the higher surface hydrophobicity and the lower polarity were conducive to biochar separation from water. The Cd removal method can provide efficient adsorption and rapid separation, making it possible to use biochar in water treatment.

Separation of chemical constituents in Bidens pilosa Linn. var. radiata Sch. Bip. by elution-extrusion counter-current chromatography using two new three-phase solvent systems.

Two new three-phase solvent systems combined with elution-extrusion counter-current chromatography mode were used to study the chemical constituents in Bidens pilosa Linn. var. radiata Sch. Bip. The first novel solvent system consisted of n-hexane, acetonitrile, chloroform, and water in a ratio of 5:5:1:5, which was selected for elution-extrusion counter-current chromatography to separate the n-hexane extraction part. A total of six constituents were obtained from this part in the up phase as the stationary phase and the middle phase as the mobile phase. The second novel solvent system, composed of n-hexane-butyl acetate-acetonitrile-water (3:1:4:3, v/v/v/v), was used for separating ethyl acetate extract of Bidens pilosa Linn. var. radiata Sch. Bip. Eight compounds were successfully isolated using elution-extrusion counter-current chromatography elution-extrusion mode. Fourteen chemical constituents were identified as 2-ß-D-glucopyranosytoxy-1-hydroxy-5(E)-tridecene-7,9,11-triyne (Y1), 3-ß-D-glucopyranosyloxy -1-hydroxy-6(E)-tetradecene-8,10,12-triyne (Y2), 1, 2-dihydroxy-5(E)-tridecene-7,9, 11-triyne (Y3), isorhamnetin (Y4), kaempferol (Y5), icthyothereolacetate (Y6), quercetin-3-O-ß-D- galactopyranosyl-7-O-ß-D-glucopyranoside (W1), quercetin 3-O-ß-L-rhamnopyranoside (W2), neosperidin dihydrochalcone (W3), quercetin (W4), quercetagetin-3,6,4' -trimethoxyl- 7-O-ß-D-glucopyranoside (W5), taxifolin (W6), luteolin (W7), and apigenin (W8) by spectra of 1 H-NMR and 13 C-NMR data. Among them, compounds Y1, Y2, Y3, and Y6 belong to polyacetylene compounds, and the rest were flavonoids. In addition, counter-current chromatography has been used to separate polyacetylene compounds for the first time. All compounds in this method were isolated from Bidens pilosa Linn. var. radiata Sch. Bip. for the first time.

Preparation of magnetic hydrochar derived from iron-rich Phytolacca acinosa Roxb. for Cd removal.

Considering that hyperaccumulators can accumulate high concentrations of iron salt, they can successfully obtain magnetic hydrochar from iron-rich hyperaccumulators. In this study, iron-rich biomass was obtained by irrigating Phytolacca acinosa Roxb. using iron salt. Magnetic nano-Fe3O4 hydrochar was prepared from iron-rich Phytolacca acinosa Roxb. via hydrothermal carbonization to remove Cd. The characterization results showed that the synthesized magnetic nanoparticles had an average size of 2.62 ± 0.56 nm and N elements were doped into magnetic nano-Fe3O4 hydrochar with abundant oxygenic groups. Cd adsorption on magnetic nano-Fe3O4 hydrochar was better fitted using the Langmuir isotherm and the pseudo-second-order kinetic model. The maximum adsorption capacity was 246.6 mg g-1 of Cd. The research confirmed that Cd adsorption was controlled by multiple mechanisms from the jar test, transmission electron microscopy mapping, scanning electron microscopy-energy dispersive X-ray spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. CdCO3 crystals can be formed after adsorption, indicating that surface precipitation played an important role in Cd adsorption. The abundance of O atoms and the doping of N atoms on the hydrochar surface were conducive to Cd adsorption, indicating that the mechanisms were related to surface complexation and electrostatic attraction. In addition, the significant decrease in Na+ content after Cd adsorption illustrated that ion exchange had a non-negligible effect on Cd adsorption. This study not only provides a strategy for preparing magnetic nano-Fe3O4 hydrochar derived from iron-rich plants but also verifies multiple Cd adsorption mechanisms using magnetic nano-Fe3O4 hydrochar.

Intervention of Uncaria and Its Components on Liver Lipid Metabolism in Spontaneously Hypertensive Rats.

Uncaria rhynchophylla (Miq.) Miq. ex Havil is widely used in the treatment of hypertension. The Uncaria extract and its bioactives, rhynchophylline and isorhynchophylline, reduced the blood pressure and fatty content in liver cells. In the present study, the antihypertensive effects of Uncaria ethanol extract (UET), rhynchophylline (RT) and isorhynchophylline (IT) were investigated in spontaneously hypertensive rats (SHR) using UPLC-Q-Orbitrap/MS based lipidomics approach. Histological changes in the liver were evaluated. Cytolysis and fatty degeneration in the liver tissues were observed in the SHR group. Lipid species in WKY, SHR treated with UET, RT, and IT were plotted to obtain the Orthogonal Projections to Latent Structures Discriminant Analysis (OPLS-DA) score plots. Fifty-six endogenous metabolites in the liver such as glycerides, glycerophospholipids, unsaturated fatty acids, and sphingomyelins were selected as potential hypertension associated biomarkers. In order to further explore the metabolite targets of UET for antihypertensive, student's t test and correlation analysis were performed to recognize the pattern recognition and to select the significant metabolites. Similar and prolonged reduction in blood pressure was observed in all SHR groups treated with UET, RT, and IT, while the metabolite profiles were perturbed slightly compared to that of the untreated SHR. Further analysis showed that only a few common components were observed in both RT and IT, which showed similar antihypertensive effect in spite of the distinct metabolic pathways. These results help in understanding the mechanisms of isomeric ingredients in exhibiting the antihypertensive effect but with different targets.

The Importance of Hand Exposures to Absorbed Dosage of Hand Harvesters.

Fruit harvesters' primary pesticide exposure results from direct dermal and clothing contact with foliar residues. The transfer of pesticide residues from foliage to strawberry harvesters' hands and their subsequent dissipation under normal occupational conditions in the field was examined. The effectiveness of latex gloves as sampling dosimeters was evaluated and compared with bare-handed harvester exposures. After application of malathion and fenpropathrin insecticides on strawberry fields, resulting harvester exposures using four independent methods were studied. Between d 4 (preharvest interval, PHI) and d 7 after pesticide application, (1) dislodgeable foliar residues, (2) pesticide residues accumulating on the gloves, and (3) end-of-shift harvester hand-wash residues decreased by 90, 75, and 85%, respectively. In contrast, the 7-d decline in excreted urine metabolites was only 43% for gloved harvesters and 29% for barehanded ones. In addition, gloved harvesters displayed 23% lower biomonitored exposures than barehanded ones, demonstrating that latex gloves are an effective protective barrier against surface residues. Since malathion and its metabolites are readily excreted, data indicated that there were likely other sources of excreted malathion breakdown products present on foliar surfaces after dissipation of malathion itself.

Fate and distribution of fipronil on companion animals and in their indoor residences following spot-on flea treatments.

Use of fipronil {5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-trifluoromethyl)sulfinyl]-1H-pyrazole-3-carbonitrile CAS 120068-37-3} topical pet products on dogs and cats introduces low level residues into residences. Distribution and fate studies of fipronil on pets and in residences were performed to evaluate potential determinants of human exposure. Fipronil, desulfinyl fipronil, fipronil sulfone and fipronil sulfide were measured on hair clippings and brushed hair. The derivatives usually represented <10% of fipronil applied. Cotton gloves worn over impervious nitrile gloves, cotton cloths placed indoors in locations frequented by pets, and cotton socks worn by residents as direct dosimeters collected fipronil and its derivatives listed above in low amounts during 4-week study periods. Subsequent acid hydrolysis urine biomonitoring did not reveal significant excretion of biomarkers at ppb levels. The human exposure potential of fipronil is low relative to levels of health concern.

Occurrence of DDA in DDT-contaminated sediments of the Southern California Bight.

DDT, DDE and some additional lipophilic derivatives are recognized contaminants in sediments of Southern California Bight (SCB). Only about 10% of total DDTs discharged into the SCB are accounted for using available monitoring data (sediment, water, and biota). DDA represented up to 0.03% DDTs (DDT/DDE/DDD) in SCB surface sediments (top 2 cm) in amounts up to 76 µg DDA/kg dry weight. Highest DDA levels were found where DDT and DDD levels were maximal at the primary wastewater outfall indicating a natural precursor-product relationship for DDT and DDA. Still culture of SCB sediment revealed limited DDA formation following DDT fortification. DDA residues have also been found in contaminated Long Island, NY sediments provided by USGS. The formation of DDA and its potential release from sediments may be significant in resolution of uncertainties concerning the natural recovery of sediments in DDT-contaminated environments.

Glove accumulation of pesticide residues for strawberry harvester exposure assessment.

We investigated the accumulation of pesticide residues on rubber latex gloves that are used by strawberry harvesters to protect their skin, reduce pesticide exposure and promote food safety. Gloves accumulated residues of 16 active ingredients including azoxystrobin, bifenthrin, boscalid, captan, cyprodinil, fenhexamid, fenpropathrin, fludioxonil, hexythiazox, malathion, methomyl, naled, propiconazole, pyraclostrobin, quinoline, and quinoxyfen at different times. Glove residue accumulation (t(½) 2.8-3.7 d) was very similar to the dissipation of DFRs (t(½) 2.1-3.0 d) during the first 3 weeks after malathion applications. Dermal malathion dose was 0.2 mg/kg at the preharvest interval and declined to trace levels during the following 3 months. Glove accumulation of malathion indicated trace surface residue availability and was used to assess the relationship between dislodgable foliar residues and potential hand exposure.

Concurrent 2,4-D and triclopyr biomonitoring of backpack applicators, mixer/loader and field supervisor in forestry.

Two herbicides, 2,4-D and triclopyr esters (application ratio 1.6:1 acid equivalents) were applied as a tank mix by a crew of 8 backpack sprayer applicators, a mixer/loader, and a field supervisor. The crew was employed in a conifer release program in northern California during the summer of 2002. Biomonitoring (urine, 24 h) utilized 2,4-D and triclopyr (a.e.) as rapidly excreted exposure biomarkers. The absorbed dosages of 2,4-D and triclopyr were calculated based upon cotton whole body suits and biomonitoring. Dosages based upon accumulation of the herbicides on body suits averaged 42.6 µg (a.e.) 2,4-D/kg-d and 8.0 µg (a.e.) triclopyr/kg-d. Six consecutive days of concurrent urine collections showed that backpack applicators excreted an average of 11.0 µg (a.e.) 2,4-D/kg-d and 18.9 µg (a.e.) triclopyr/kg-d. Estimates based upon curve fitting were 17.1 and 29.3 µg (a.e.)/kg-d, respectively. Results suggest that passive dosimetry for 2,4-D consistently overestimated the dosage measured using biomonitoring by a factor of 2-3 fold, while for triclopyr, passive dosimetry underestimated the absorbed dose based on biomonitoring by a factor of 2-4 fold.

Pilot biomonitoring of adults and children following use of chlorpyrifos shampoo and flea collars on dogs.

Pesticide handlers and pet owners who use products such as shampoos and dips and insecticide-impregnated collars to treat and control fleas on companion animals are exposed to a variety of active ingredients. Chlorpyrifos exposures of adults and children were measured using urine biomonitoring following use of over-the-counter products on dogs. Age and gender-specific measurements of urinary 3, 5, 6-trichloro-2-pyridinol (TCPy) revealed modest elevations of biomarker excretion following shampoo/dips. Smaller TCPy increments were measured following application of impregnated dog collars. The extent of indoor activity and potential pet contact were important determinants of urine biomarker level. Children without direct pet contact excreted more TCPy following collar application. Pet collars may be a source of indoor surface contamination and human exposure. Children excreted up to 4 times more TCPy than adults when urine volumes were adjusted using age-specific creatinine excretion levels. Although chlorpyrifos is no longer used in the United States in pet care products, results of this research provide perspective on the extent of human exposure from similar pet care products. These pilot studies demonstrated that pet care products such as insecticidal shampoos and dips and impregnated collars may expose family members to low levels of insecticide relative to toxic levels of concern.

2,2-bis(4-Chlorophenyl)acetic acid (DDA), a water-soluble urine biomarker of DDT metabolism in humans.

DDT metabolism in humans yields DDA as the principal urinary metabolite and potential exposure biomarker. A method for DDA analysis in human urine was developed using pentafluorobenzyl bromide and diisopropylethyl amine. Dried hexane extracts were reacted for 1 hour at room temperature. The stable DDA-pentafluorobenzyl-ester derivative was analyzed by gas chromatography-electron capture detector (GC-ECD) and confirmed by gas chromatography-mass spectrometry (GC-MS) in selective ion monitoring mode. The limit of detection for DDA was 0.1 microg/L urine by GC-ECD and 2 microg/L urine by GC-MS, with a relative standard deviation of 12%. Urine specimens from DDT applicators in Swaziland and South Africa were analyzed to evaluate the method. The mean DDA levels during the spray season and post season were 59 and 11 microg/L, respectively. These results must be interpreted cautiously because different groups of workers provided urine specimens in each case. The DDA urinalysis may be a feasible monitoring strategy for low-level occupational and residential DDT exposure assessment in antimalaria campaigns.

[Quality of life after cochlear implantation in postlingually deaf adults].

OBJECTIVE: To evaluate the quality of life after cochlear implantation in adult cochlear implant recipients and to assess the applicability of Nijmegen Cochlear implant Questionnaire (NCIQ). METHODS: Thirty-two postlingually deaf patients, 19 males and 13 females, underwent cochlear implantation with the age at operation of 35.27 (18-66) during the period from 1996 to the end of 2006. NCIQ was used to investigate the application of the equipment, hearing ability, and emotional exchange ability. RESULTS: All of the patients used their cochlear implants for 16 h every day on average with an experience in using such implant of more than 6 months. Improvement was seen in sound recognition, speech recognition, confidence, daily life, social exchange, and emotional behavior ability at different degrees. The improvement of confidence was very obvious. The speech communication ability of those with a hearing deprivation time longer than 5 years was lower than that of those with a shorter hearing deprivation time. Age and educational level did not influence the efficiency. CONCLUSION: Cochlear implantation is a cost effective intervention in the postlingually deaf adults. NCIQ test can be used to evaluate the quality of life among postlingually deaf adult cochlear implant recipients in China.