Chemical Constituents of Murraya tetramera Huang and Their Repellent Activity against Tribolium castaneum.

Sixteen compounds were isolated from the leaves and stems of Murrayatetramera Huang. Based on the NMR and MS spectral results, the structures were determined. It was confirmed that the isolated compounds included three new compounds (9, 10 and 13) and one new natural product (8), which were identified asmurratetra A (9), murratetra B (10), murratetra C (13) and [2-(7-methoxy-2-oxochromen-8-yl)-3-methylbut-2-enyl]3-methylbut-2-enoate (8), respectively. Meanwhile, the repellent activity against Tribolium castaneum was investigated for 13 of these isolated compounds. The results showed that the tested compounds had various levels of repellent activity against T. castaneum. Among them, compounds 1 (4(15)-eudesmene-1ß,6α-diol), 11 (isoferulic acid) and 16 (2,3-dihydroxypropyl hexadecanoate) showed fair repellent activity against T. castaneum. They might be considered as potential leading compounds for the development of natural repellents.

Chemical Constituents and Insecticidal Activities of Ajania fruticulosa Essential Oil.

The insecticidal activity and chemical constituents of the essential oil from Ajania fruticulosa were investigated. Twelve constituents representing 91.0% of the essential oil were identified, and the main constituents were 1,8-cineole (41.40%), (+)-camphor (32.10%), and myrtenol (8.15%). The essential oil exhibited contact toxicity against Tribolium castaneum and Liposcelis bostrychophila adults with LD50 values of 105.67 µg/adult and 89.85 µg/cm(2) , respectively. The essential oil also showed fumigant toxicity against two species of insect with LC50 values of 11.52 and 0.65 mg/l, respectively. 1,8-Cineole exhibited excellent fumigant toxicity (LC50  = 5.47 mg/l) against T. castaneum. (+)-Camphor showed obvious fumigant toxicity (LC50  = 0.43 mg/l) against L. bostrychophila. Myrtenol showed contact toxicity (LD50  = 29.40 µg/cm(2) ) and fumigant toxicity (LC50  = 0.50 mg/l) against L. bostrychophila. 1,8-Cineole and (+)-camphor showed strong insecticidal activity to some important insects, and they are main constituents of A. fruticulosa essential oil. The two compounds may be related to insecticidal activity of A. fruticulosa essential oil against T. castaneum and L. bostrychophila.

[The Concentration Effect of Near-Infrared Quantum Cutting Luminescence of Tm(3+) Ion Sensitized with Bi(3+) Ion in YNbO(4) Phosphor].

Searching for new energy source is one of the most important projects faced by the global, while the most ideal new energy source is solar cell. Near infrared quantum cutting luminescence method can doubly transfer large energy photon which is not sensitive to Si or Ge solar cell to small energy photon which is sensitive to Si or Ge solar cell. It can resolve the spectral mismatch problem and largely enhance solar cell efficiency. Therefore, it is significant. The concentration effect of near-infrared quantum cutting luminescence of Tm3+Bi3+∶YNbO4 phosphor is reported in present manuscript. Through the measurement of excitation and emission spectra, it is found that the Tm0.058Bi0.010Y0.932NbO4 powder phosphor has intense 1 820.0 nm near-infrared quantum cutting luminescence. Further analysis finds they are multi-photon quantum cutting luminescence induced by the cross-energy transfer process. The population of 1G4 energy level may be directly transferred to lower energy level mainly through {1G4­3H4, 3H6­3H5} and {1G4­3H5, 3H6­3H4} cross-energy transfer processes, i. e. one population of the 1G4 energy level may effectively lead to two populations, which are positioned at the 3H4 and 3H5 energy levels, respectively, mainly through {1G4­3H4, 3H6­3H5} and {1G4­3H5, 3H6­3H4} cross-energy transfer processes. This may also effectively lead to three populations of the 3F4 energy level through {3H4­3F4, 3H6­3F4} cross-energy transfer process from the 3H4 level and multi-phonon non-radiative relaxation from the 3H5 level, respectively. This results in the effective three-photon near-infrared quantum cutting of the 3F4­3H6 fluorescence of Tm3+ ion. It's also found that the sensitization action of Bi3+ ion to Tm3+ ion is very strong. The enhancement of the 1 820.0 nm near-infrared quantum cutting luminescence, of Tm0.058Bi0.010Y0.932NbO4 relative to Tm0.005Y0.995NbO4, is about 175.5 times, when excited by the 302.0 nm light. The present results are significant for the exploration of the next-generation multi-photon near-infrared quantum cutting germanium solar cell.

Contact Toxicity and Repellency of the Essential Oil of Dictamnus dasycarpus Roots from China against Two Stored-Product Insects.

During our screening program for new agrochemicals from traditional medicinal herbs, Dictamnus dasycarpus was found to possess contact toxicity and repellent activity against the cigarette beetle Lasioderma serricorne and the booklouse Liposcelis bostrychophila. The essential oil obtained by hydrodistillation of D. dasycarpus roots was characterized by GC-FID and GC/MS analyses, and the main components identified were syn-7-hydroxy-7-anisylnorbornene (1, 49.9%), 1,3,4,5,6,7-hexahydro-2H-inden-2-one (2, 11.6%), 5,6-diethenyl-1-methylcyclohexene (3, 7.4%), and 3,9-dimethyltricyclo[4.2.1.1(2,5)]dec-3-en-9-ol (4, 6.35%). The D. dasycarpus root oil exhibited strong contact toxicity against L. serricorne adults and L. bostrychophila, with LD50 values of 12.4 µg/adult and 27.2 µg/cm(2), respectively. Moreover, the essential oil also showed strong repellency against both stored-product insects tested.

Insecticidal and repellant activities of polyacetylenes and lactones derived from Atractylodes lancea rhizomes.

During a screening program for new agrochemicals from Chinese medicinal herbs and local wild plants, the petroleum ether (PE) extract of Atractylodes lancea (Thunb.) rhizomes was found to possess repellent and contact activities against Tribolium castaneum adults. Bioactivity-directed chromatographic separation of PE extract on repeated silica-gel columns led to the isolation of two polyacetylenes, atractylodin and atractylodinol (1 and 2, resp.), and two lactones, atractylenolides II and III (3 and 4, resp.). The structures of the compounds were elucidated based on NMR spectra. The four isolated compounds were evaluated for their insecticidal and repellent activities against T. castaneum. Atractylodin exhibited strong contact activity against T. castaneum adults with a LD50 value of 1.83 µg/adult. Atractylodin and atractylenolide II also possessed strong repellenct activities against T. castaneum adults. After 4-h exposure, >90% repellency was achieved with atractylodin at a low concentration of 0.63 µg/cm(2) . The results indicated that atractylodin (1) and atractylenolide II (3) have a good potential as a source for natural repellents, and 1 has the potential to be developed as natural insecticide.

Contact toxicity and repellency of the essential oil from Mentha haplocalyx Briq. against Lasioderma serricorne.

The chemical composition of the essential oil obtained by hydrodistillation from the aerial parts of Mentha haplocalyx was investigated by GC-FID and GC/MS analyses. In sum, 23 components, representing 92.88% of the total oil composition, were identified, and the main compounds were found to be menthol (59.71%), menthyl acetate (7.83%), limonene (6.98%), and menthone (4.44%). By bioassay-guided fractionation (contact toxicity), three compounds were obtained from the essential oil and identified as menthol, menthyl acetate, and limonene. The essential oil and the three isolated compounds exhibited potent contact toxicity against Lasioderma serricorne adults, with LD50 values of 16.5, 7.91, 5.96, and 13.7 µg/adult, respectively. Moreover, the oil and its isolated compounds also exhibited strong repellency against L. serricorne adults. At the lower concentrations tested and at 2 h after exposure, menthol showed even significantly stronger repellency than the positive control DEET. The study revealed that the bioactivity properties of the essential oil can be attributed to the synergistic effects of its diverse major and minor components, which indicates that the M. haplocalyx oil and its isolated compounds have potential for the development as natural insecticides and/or repellents to control insects in stored grains and traditional Chinese medicinal materials.

[Three photons quantum-cutting system on the rear surface of cells to improve the efficiencies of solar cells].

The authors present a solar cell model with a three photons quantum-cutting system on the rear surface, then the method of calculation of limiting efficiencies was used to get the maximum efficiency 58.58% at the band gap Eg=0.9315 eV, and in contrast with two-photons quantum-cutting system, it is greatly improved. The result can prove that the three-photons quantum-cutting has a great sense to improve the efficiencies of solar cells. It is the exciting development for us to find out the useful luminescence materials to get the high efficiency.

Chemical constituents and activities of the essential oil from Myristica fragrans against cigarette beetle Lasioderma serricorne.

Essential oil extracted from nutmeg seeds (Myristica fragrans Houtt.) by hydrodistillation was subjected to GC/MS and GC analysis. A total of 27 constituents were identified, of which eugenol (19.9%), methylisoeugenol (16.8%), methyleugenol (16.7%), sabinene (11.8%), and terpinen-4-ol (8.5%) were the major components. The essential oil was tested against Lasioderma serricorne for insecticidal and repellent activity, the LD50 value at the end of 24 h exposure period was 19.3 µg/adult. Six active compounds were isolated by bioassay-guided fractionation. They were identified as eugenol (1), methyleugenol (2), methylisoeugenol (3), elemicin (4), myristicin (5), and safrole (6). Among these isolates, 4 showed the strongest contact toxicity against L. serricorne adults with an LD50 value of 9.8 µg/adult. Repellency of crude oil and active compounds were also determined. Compounds 1, 2, 4, and 5 were strongly repellent against the cigarette beetle and exhibited the same level of repellency compared with the positive control, DEET. The results indicate that the essential oil of M. fragrans and its active constituents have potential for development as natural insecticides and repellents to control L. serricorne.

Cytotoxic compounds isolated from Murraya tetramera Huang.

A new compound and seven known compounds were isolated from Murraya tetramera Huang for the first time, and they were identified with NMR and MS spectral analysis. It was confirmed that the new compound was 10-methoxy-7-methyl-2H-benzo[g]chromen-2-one (3) and the others were ß-eudesmol (1), trans-3ß-(1-hydroxy-1-methylethyl)-8aß-methyl-5-methylenedecalin-2-one (2), 5,7-dimethoxy-8-[(Z)-3'-methyl-butan-1',3'-dienyl]coumarin (4), 7-geranyloxy-6-methoxycoumarin (5), 5,7-dimethoxy-8-(3-methyl-2-oxo-butyl)coumarin (6), murrangatin acetate (7) and toddalenone (8). Furthermore, the cytotoxic activity against human lung adenocarcinoma (A549), human hepatocellular carcinoma cells (SMMC-7721), human bladder tumor cells (EJ), human cervical carcinoma cells (HeLa), and human B-lineage acute lymphoblastic leukemia 1 cells (BALL-1) was evaluated for all compounds. It was found that five of them displayed various degrees of cytotoxicity against different testing targets. Compound 1 showed significant cytotoxic activity against the five cell lines (A549, SMMC-7721, EJ, Hela and BALL-1). Compounds 2 and 5 showed significant cytotoxicity against three cell lines (A549, SMMC-7721 and BALL-1). Compound 4 showed significant cytotoxicity against three cell lines (A549, EJ and BALL-1). However, compound 3 only showed fair cytotoxicity against the BALL-1 cell line. The structure-active relationships were investigated as well. These active compounds might be potential lead compounds for the treatment of cancer.

[Determination of 12 prohibited veterinary drug residues in pig urine by ultra high performance liquid chromatography-tandem mass spectrometry].

A method was established for the simultaneous detection of 12 prohibited veterinary drugs, including ß2-receptor agonists, nitrofuran metabolites, nitroimidazoles, chlorpromazine, and chloramphenicol, in pig urine. The sample was pretreated by enzymolysis, acid hydrolysis/derivatization, and liquid-liquid extraction combined with solid-phase extraction. Detection was performed using ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Ammonium acetate solution (0.2 mol/L, 4.5 mL) and ß-glucuronidase/aryl sulfatase (40 µL) were added to the sample, which was subsequently enzymolized at 37 ℃ for 2 h. Then, 1.5 mL of 1.0 mol/L hydrochloric acid solution and 100 µL of 0.1 mol/L o-nitrobenzaldehyde solution were added to the sample. The mixture was incubated at 37 ℃ for 16 h, and the analytes were extracted with 8 mL of ethyl acetate by liquid-liquid extraction. The lower aqueous phase obtained after extraction was extracted and purified using a mixed cation-exchange solid-phase extraction column. The extracts were combined, the extraction solution was blow-dried with nitrogen, and the residue was redissolved for determination. The samples were analyzed under multiple-reaction monitoring mode with both positive and negative electrospray ionization, and quantified using an isotope internal standard method. The correlation coefficients (r) of the 12 compounds were >0.99. The limits of detection (LODs) and quantification (LOQs) of chloramphenicol were 0.05 and 0.1 µg/L, respectively, and the LODs and LOQs of the other compounds were 0.25 and 0.5 µg/L, respectively. The mean recoveries and RSDs at 1, 2, and 10 times the LOQ were 83.6%-115.3% and 2.20%-12.34%, respectively. The proposed method has the advantages of high sensitivity, good stability, and accurate quantification; thus, it is suitable for the simultaneous determination of the 12 prohibited veterinary drug residues in pig urine.

Chemical composition and nematicidal activity of essential oil of Agastache rugosa against Meloidogyne incognita.

The aim of this research was to determine the chemical composition and nematicidal activity of essential oil of Agastache rugosa flowering aerial parts against the root knot nematode, Meloidogyne incognita, and to isolate and identify any nematicidal constituents from the essential oil. The essential oil of A. rugosa aerial parts was obtained by hydrodistillation and analyzed by GC-FID and GC-MS. A total of 37 components of the essential oil were identified, with the principal compounds being methyleugenol (50.51%), estragole (8.55%), and eugenol (7.54%), followed by thymol (3.62%), pulegone (2.56%), limonene (2.49%) and caryophyllene (2.38%). Based on bioactivity-guided fractionation, the three active constituents were isolated from the essential oil and identified as methyleugenol, estragole and eugenol. The essential oil of A. rugosa exhibited strong nematicidal activity against M. incognita, with a LC50 value of 47.3 µg/mL. The components eugenol (LC50 = 66.6 µg/mL) and methyleugenol (LC50 = 89.4 µg/mL) exhibited stronger nematicidal activity against M. incognita (LC50 = 185.9 µg/mL). The results indicate that the essential oil of A. rugosa aerial parts and its constituent compounds have potential for development into natural nematicides for control of the root knot nematode.

Identification of repellent and insecticidal constituents of the essential oil of Artemisia rupestris L. aerial parts against Liposcelis bostrychophila Badonnel.

The aim of this research was to determine the chemical composition and insecticidal and repellent activity of the essential oil of Artemisia rupestris L. aerial parts against the booklice Liposcelis bostrychophila Badonnel and isolation of insecticidal and repellent constituents from the essential oil. The essential oil of A. rupestris was obtained by hydrodistillation and analyzed by GC-MS. A total of 30 components of the essential oil of A. rupestris was identified and the principal compounds in the essential oil were α-terpinyl acetate (37.18%), spathulenol (10.65%), α-terpineol (10.09%), and linalool (7.56%), followed by 4-terpineol (3.92%) and patchoulol (3.05%). Based on bioactivity-guided fractionation, the four active constituents were isolated from the essential oil and identified as α-terpineol, α-terpinyl acetate, 4-terpineol and linalool. The essential oil of A. rupestris exhibited contact toxicity against L. bostrychophila with LD50 value of 414.48 µg/cm². α-Terpinyl acetate (LD50 = 92.59 µg/cm²) exhibited stronger contact toxicity against booklice than α-terpineol (LD50 = 140.30 µg/cm²), 4-terpineol (LD50 = 211.35 µg/cm²), and linalool (LD550 = 393.16 µg/cm²). The essential oil of A. rupestris (LC50 = 6.67 mg/L air) also possessed fumigant toxicity against L. bostrychophila while the four constituents, 4-terpineol, α-terpineol, α-terpinyl acetate and linalool had LC50 values of 0.34, 1.12, 1.26 and 1.96 mg/L air, respectively. α-Terpinol and α-terpinyl acetate showed strong repellency against L. bostrychophila, while linalool and 4-terpinol exhibited weak repellency. The results indicate that the essential oil of A. rupestris aerial parts and its constituent compounds have potential for development into natural insecticides or fumigants as well as repellents for control of insects in stored grains.

Cytotoxic constituents from the stems of Clausena lansium (Lour.) Skeels.

Six compounds were isolated from the stems of Clausena lansium (Lour.) Skeels by repeated sillica gel column chromatography. Their chemical structures were elucidated on the basic of physicochemical and spectroscopic data. Among them, 8-geranyloxypsolaren (3) and 2-methoxy-1-(3-methyl-buten-1-yl)-9H-carbazole-3-carbaldehyde (6) were isolated for the first time from this plant. These compounds were screened for cytotoxicity in human cervical cancer (Hela), leukemia (K562), lung cancer (A549), non-small lung carcinoma (H1299) and liver cancer (SMMC-7721). Within the series of cytotoxic tests, compounds 4-6 displayed potent cytotoxic activity against H1299 and SMMC-7721, with the IC50 values of 6.19 to 26.84 µg/mL.

Mosquito larvicidal activity of alkaloids and limonoids derived from Evodia rutaecarpa unripe fruits against Aedes albopictus (Diptera: Culicidae).

In recent years, uses of environment friendly and biodegradable natural insecticides of plant origin have received renewed attention as agents for vector control. During a screening program for new agrochemicals from Chinese medicinal herbs and local wild plants, the ethanol extract of Evodia rutaecarpa Hook f. et Thomas (Rutaceae) unripe fruits was found to possess larvicidal activity against the mosquitoes. The aim of this research was to determine larvicidal activity of the ethanol extract of E. rutaecarpa unripe fruits and the isolated constituents against the larvae of the Culicidae mosquito Aedes albopictus. The powder, 5 kg of the fruit material, was extracted with 30 l of 95 % ethanol, filtered, and evaporated to dryness in a rotary vacuum evaporator. The crude extract was then partitioned between methanol-water and n-hexane. The n-hexane fraction was evaporated off to given n-hexane extract. The aqueous layer was repartitioned with chloroform to provide chloroform extract after evaporation of the solvent. Further partitioning with ethyl acetate gave a residue after evaporation of the solvent. Bioactivity-directed chromatographic separation of chloroform extract on repeated silica gel columns led to the isolation of three alkaloids (evodiamine, rutaecarpine, and wuchuyuamide I) and two limonoids (evodol and limonin). The structures of the constituent compounds were elucidated based on high-resolution electron impact mass spectrometry and nuclear magnetic resonance. Evodiamine, rutaecarpine, and wuchuyuamide I exhibited strong larvicidal activity against the early fourth instar larvae of A. albopictus with LC(50) values of 12.51, 17.02, and 26.16 µg/ml, respectively. Limonin and evodol also possessed larvicidal activity against the Asian tiger mosquitoes with LC(50) values of 32.43 and 52.22 µg/ml, respectively, while the ethanol extract had a LC(50) value of 43.21 µg/ml. The results indicated that the ethanol extract of E. rutaecarpa and the five isolated constituents have a good potential as a source for natural larvicides.

Essential oil composition and larvicidal activity of Saussurea lappa roots against the mosquito Aedes albopictus (Diptera: Culicidae).

In recent years, uses of environment friendly and biodegradable natural insecticides of plant origin have received renewed attention as agents for vector control. The aim of this research was to determine larvicidal activity of the essential oil derived from roots of Saussurea lappa (Compositae) and the isolated constituents against the larvae of the Culicidae mosquito Aedes albopictus. Essential oil of S. lappa roots was obtained by hydrodistillation and analyzed by gas chromatography (GC) and GC-mass spectrometry (MS). A total of 39 components of the essential oil of S. lappa roots were identified. The essential oil has higher content of (79.80%) of sesquiterpenoids than monoterpenoids (13.25%). The principal compounds in S. lappa essential oil were dehydrocostus lactone (46.75%), costunolide (9.26%), 8-cedren-13-ol (5.06%), and α-curcumene (4.33%). Based on bioactivity-directed fractionation, dehydrocostus lactone and costunolide were isolated from S. lappa essential oil. Dehydrocostus lactone and costunolide exhibited strong larvicidal activity against A. albopictus with LC(50) values of 2.34 and 3.26 µg/ml, respectively, while the essential oil had an LC(50) value of 12.41 µg/ml. The result indicated that the essential oil of S. lappa and the two isolated constituents have potential for use in control of A. albopictus larvae and could be useful in search of newer, safer and more effective natural compounds as larvicides.

Chemical composition and insecticidal activity against Sitophilus zeamais of the essential oils derived from Artemisia giraldii and Artemisia subdigitata.

The aim of this research was to determine the chemical composition and insecticidal activity of the essential oils derived from flowering aerial parts of Artemisia giraldii Pamp. and A. subdigitata Mattf. (Family: Asteraceae) against the maize weevil (Sitophilus zeamais Motsch.). Essential oils of aerial parts of A. giraldii and A. subdigitata were obtained from hydrodistillation and investigated by GC and GC-MS. A total of 48 and 33 components of the essential oils of A. giraldii and A. subdigitata were identified, respectively. The principal compounds in A. giraldii essential oil were ß-pinene (13.18%), iso-elemicin (10.08%), germacrene D (5.68%), 4-terpineol (5.43%) and (Z)-ß-ocimene (5.06%). 1,8-Cineole (12.26%) and α-curcumene (10.77%) were the two main components of the essential oil of A. subdigitata, followed by ß-pinene (7.38%), borneol (6.23%) and eugenol (5.87%). The essential oils of A. giraldii and A. subdigitata possessed fumigant toxicity against the maize weevils with LC50 values of 6.29 and 17.01 mg/L air, respectively. The two essential oils of A. giraldii and A. subdigitata also exhibited contact toxicity against S. zeamais adults with LD50 values of 40.51 and 76.34 µg/adult, respectively. The results indicated that the two essential oils show potential in terms of fumigant and contact toxicity against grain storage insects.

Chemical composition and insecticidal activity of the essential oil of Illicium pachyphyllum fruits against two grain storage insects.

The aim of this research was to determine chemical composition and insecticidal activity of the essential oil of Illicium pachyphyllum fruits against two grain storage insects, Sitophilus zeamais and Tribolium castaneum, and to isolate any insecticidal constituents from the essential oil. The essential oil of I. pachyphyllum fruits was obtained by hydrodistillation and analyzed by GC-MS. A total of 36 components of the essential oil were identified, with the principal compounds in the essential oil being trans-ρ-mentha-1(7),8-dien-2-ol (24.56%), D-limonene (9.79%), caryophyllene oxide (9.32%), and cis-carveol (5.26%) followed by ß-caryophyllene (4.63%) and bornyl acetate. Based on bioactivity-guided fractionation, the three active constituents were isolated and identified as trans-ρ-mentha-1(7),8-dien-2-ol, D-limonene and caryophyllene oxide. The essential oil of I. pachyphyllum fruits exhibited contact toxicity against S. zeamais and T. castaneum adults, with LD(50) values of 17.33 µg/adult and 28.94 µg/adult, respectively. trans-p-Mentha-1(7),8-dien-2-ol (LD(50) = 8.66 µg/adult and 13.66 µg/adult, respectively) exhibited stronger acute toxicity against S. zeamais and T. castaneum adults than either caryophyllene oxide (LD(50) = 34.09 µg/adult and 45.56 µg/adult) and D-limonene (LD(50) = 29.86 µg/adult and 20.14 µg/adult). The essential oil of I. pachyphyllum possessed fumigant toxicity against S. zeamais and T. castaneum adults with LC(50) values of 11.49 mg/L and 15.08 mg/L, respectively. trans-p-Mentha-1(7),8-dien-2-ol exhibited stronger fumigant toxicity against S. zeamais and T. castaneum adults, respectively, with LC(50) values of 6.01 mg/L and 8.14 mg/L, than caryophyllene oxide (LC(50) = 17.02 mg/L and 15.98 mg/L) and D-limonene (LC(50) = 33.71 mg/L and 21.24 mg/L). The results indicate that the essential oil of I. pachyphyllum fruits and its constituent compounds have potential for development into natural insecticides or fumigants for the control of insects in stored grains.

Antioxidant phenolic compounds from Pu-erh tea.

Eight compounds were isolated from the water extract of Pu-erh tea and their structures were elucidated by NMR and MS as gallic acid (1), (+)-catechin (2), (−)-epicatechin (3), (−)-epicatechin-3-O-gallate (4), (−)-epigallocatechin-3-O-gallate (5), (−)-epiafzelechin- 3-O-gallate (6), kaempferol (7), and quercetin (8). Their in vitro antioxidant activities were assessed by the DPPH and ABTS scavenging methods with microplate assays. The relative order of DPPH scavenging capacity for these compounds was compound 8 > compound 7 > compound 1 > compound 6 > compound 4 ≈ compound 5 > compound 2 > VC (reference) > compound 3, and that of ABTS scavenging capacity was compound 1 > compound 2 > compound 7 ≈ compound 8 > compound 6 > compound 5 > compound 4 > VC (reference) > compound 3. The results showed that these phenolic compounds contributed to the antioxidant activity of Pu-erh tea.

[Infrared multiphoton quantum cutting phenomena of rare earth materials].

Infrared quantum cutting of rare earth ion is an international hot research field. It is significant for the enhancement of solar cell efficiency and for the reduction of solar cell price. The present paper summarizes the research significance of infrared quantum cutting of rare earth ion. Based on the summarization of general principle and loss mechanism of solar cell, the possible method to enhance the solar cell efficiency by infrared quantum cutting is analyzed. Meanwhile, the present paper summarizes the infrared quantum cutting phenomena of Er3+ ion single-doped material. There is intense 4I13/2 --> 4I15/2 infrared quantum cutting luminescence of Er3+ ion when the 2H11/2 energy level is excited. The intense {2H11/2 --> 4I9/2, 4I15/2 --> 4I13/2} cross energy transfer is the main reason for the result in the high quantum cutting efficiency when the 2H11/2 energy level is excited.

Tai Chi Quan Versus Physical Therapy on Pain and Cognitive Performance for Elderly People With Chronic Low Back Pain: Study Protocol for a Randomized Controlled Trial.

Objectives: Chronic low back pain has become a major cause of global disability and caused a huge economic burden to society. Physical therapy is a vital strategy for rehabilitation of chronic low back pain. Although several trials have shown that Tai Chi Quan is a beneficial treatment, the comparative effectiveness of Tai Chi Quan versus physical therapy is unknown. We are conducting a randomized controlled trial to assess the effectiveness of Tai Chi Quan versus that of physical therapy in treating chronic low back pain. Methods: We will perform a single-blind randomized controlled trial on elderly people with chronic low back pain. 138 participants will be randomly assigned to the Tai Chi Quan group (60-min classes, three times per week for 12 weeks) or physical therapy group (10 min of evaluation and warm-up, 40 min of therapist-directed exercise therapy, and 10 min of relaxation, three times per week for 12 weeks) with an allocation of 1:1. The participants will be followed up for 40 weeks for the study of long-term effects. The primary outcomes include pain intensity and back-related function at 12 weeks. Secondary outcomes include lumbar quantitative sensory testing, balance, cognitive function, psychosocial function, cost-effectiveness, compliance and adverse events. We will perform the intention-to-treat analysis for withdrawal and missing data. Discussion: The study will be the first randomized trial with comparative-effectiveness of Tai Chi Quan and physical therapy for chronic low back pain. Standardized protocol, large sample size, and comprehensive outcomes are important features in this trial. This study aims to determine the feasibility and effectiveness of Tai Chi Quan for low back pain. The results of this study will be beneficial for elderly people with low back pain and medical rehabilitation personnel. Clinical Trial Registration: www.chictr.org.cn, identifier ChiCTR2000029723.