Free Radical Scavenging Activity of 4-(3,4-Dihydroxybenzoyloxymethyl)phenyl-O-β-d-glucopyranoside from Origanum vulgare and Its Protection against Oxidative Damage

4-(3,4-Dihydroxybenzoyloxymethyl)phenyl-O-β-d-glucopyranoside (DBPG), a polyphenolic glycoside, isolated from Origanum vulgare has shown 1,1-diphenyl-2-picrylhydrazyl (DPPH(?))-scavenging capacity in previous work. This study demonstrated that DBPG exhibits antioxidant activity by a series of DPPH(?), 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS(?+)), and superoxide anion radical (O(2)(?-)) radical-scavenging assays. The inhibition of lipid peroxidation (LP) by DBPG exceeded that by l-ascorbic acid (AA) in a liposome model system. Adding DBPG to mouse liver and brain tissue inhibited the formation of thiobarbituric acid reactive substances (TBARS) to a greater extent than did trolox. In the oxygen stress test, BNLCL2 and HaCaT cells pretreated with DBPG showed increased activities of glutathione peroxidase (GPx), perhaps as a result of reduction of the production of reactive oxygen species (ROS). These findings proved that DBPG had antioxidant activities and a cytoprotective effect in hepatocytes and keratinocytes, suggesting that DBPG may be a useful food and cosmetic additive.     

Cytotoxic sesterterpenoids from a sponge Hippospongia sp

One new pentacyclic sesterterpene, hippospongide A (1), and one new scalarane sesterterpenoid, hippospongide B (2), along with six previously reported known scalarane-type sesterterpenes (3-8), were isolated from a sponge Hippospongia sp. The structures of these compounds were elucidated on the basis of their spectroscopic data and comparison of the NMR data with those of known analogues. These metabolites are the first pentacyclic sesterterpene and scalarane-type sesterterpenes to be reported from this genus. Compounds 3-5 exhibited significant cytotoxicity against DLD-1, HCT-116, T-47D and K562 cancer cell lines.     

Optical clocks and relativity

Observers in relative motion or at different gravitational potentials measure disparate clock rates. These predictions of relativity have previously been observed with atomic clocks at high velocities and with large changes in elevation. We observed time dilation from relative speeds of less than 10 meters per second by comparing two optical atomic clocks connected by a 75-meter length of optical fiber. We can now also detect time dilation due to a change in height near Earth's surface of less than 1 meter. This technique may be extended to the field of geodesy, with applications in geophysics and hydrology as well as in space-based tests of fundamental physics.     

干椒新品种筛选试验初报

在贵州省农业委员会和贵阳市蔬菜办的安排下,引进777、535、满天星等8个干椒新品种进行品种比较试验,结果表明,满天星和单生红两个品种,植株长势强、抗逆性强,果实油质光滑,品质优,含水量低,在清镇市可作小山椒发展,535和241两个品种,植株长势和抗逆性也强,果实品质也好,青果为黄绿色,是典型的泡椒类型品种,可作泡椒发展。     

In situ observations of a high-pressure phase of H2O Ice

A previously unknown solid phase of H2O has been identified by its peculiar growth patterns, distinct pressure-temperature melting relations, and vibrational Raman spectra. Morphologies of ice crystals and their pressure-temperature melting relations were directly observed in a hydrothermal diamond-anvil cell for H2O bulk densities between 1203 and 1257 kilograms per cubic meter at temperatures between -10 degrees and 50 degreesC. Under these conditions, four different ice forms were observed to melt: two stable phases, ice V and ice VI, and two metastable phases, ice IV and the new ice phase. The Raman spectra and crystal morphology are consistent with a disordered anisotropic structure with some similarities to ice VI.     

人工草地土壤水分周年变化规律的研究

本文利用人工牧草地土壤水分试验测定资料,分析研究了草地土壤水分的周年变化规律,得出草地土壤水分周年变化可划分为春季失墒期、夏季增失墒交替期、伏秋增墒期;土壤水分动态曲线波动主要受降水补给量和牧草耗水量的影响而变化,雨季降水对旱作草地土壤水分的补给起着重要作用。     

Purification, cloning, and identification of two thaumatin-like protein isoforms in jelly fig (Ficus awkeotsang) Achenes

Jelly curd used for a popular summer drink in Taiwan is prepared by extracting the pericarpial portion of jelly fig (Ficus awkeotsang Makino) achenes. The two most abundant proteins found in jelly curd have been identified as a pectin methylesterase and a chitinase. A method was developed to purify the next abundant protein by 40% ammonium sulfate precipitation and flowing through Mono Q chromatography. In sodium dodecyl sulfate-polyacrylamide gel electrophoresis analyses, the purified protein migrated as a polypeptide of 20 kDa in the absence of beta-mercaptoethanol but split into a minor polypeptide of 20 kDa and a major polypeptide of 27 kDa in the presence of this reducing agent. Two cDNA fragments encoding precursor polypeptides of two putative thaumatin-like protein isoforms were obtained by polymerase chain reaction cloning and subsequently overexpressed in Escherichia coli to generate recombinant proteins for antibody preparations. Immunological detection and mass spectrometric analyses indicated that the two split polypeptides were thaumatin-like protein isoforms encoded by the two cloned cDNA fragments.     

电取蜂毒对中华蜜蜂寿命的影响

采用QF—1型电子取毒仪,分别电刺激3～27日龄的中蜂工蜂5分钟,结果3和6日龄的工蜂寿命缩短差异不显著(P>0.05);9、12、15、18日龄的工蜂寿命缩短2.75～4.59天,差异显著(P<0.05);21、24、27日龄的工蜂寿命缩短4.50～4.75天,差异极显著(P<0.01)。     

Proportion and cluster analyses of the skull in various species of the tree shrews

The skull adaptation was functional-morphologically examined in 14 species of the tree shrews. From the data of the proportion indices, the similarities were confirmed between T. minor and T. gracilis, T. tana and T. dorsalis, and T. longipes and T. glis. We demonstrated that the splanchnocranium was elongated in terrestrial T. tana and T. dorsalis and shortened in arboreal T. minor and T. gracilis from the proportion data. In both dendrogram from the matrix of the Q-mode correlation coefficients and scattergram from the canonical discriminant analysis, the morphological similarities in the skull shape suggested the terrestrial-insectivorous adaptation of T. tana and T. dorsalis, and the arboreal adaptation of T. minor and T. gracilis. Since the osteometrical skull similarities were indicated among the three species of Tupaia by cluster and canonical discriminant analyses, the arbo-terrestrial behavior and its functional-morphological adaptation may be commonly established in T. montana, T. longipes and T. glis.