bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ir A.H. de Voogt: life and career of a radio pioneer
Authors: Strom R.G. 
Published: May 2007

AbstractThere are probably few radio astronomers who would be able to recall A.H. de Voogt, which is unfortunate, but at the same time unsurprising: for he published no original astronomical research, never carried out pioneering observations, nor is his name linked to either theoretical or instrumental breakthroughs. Yet he was described by the man who first observed the 21 cm hydrogen line from the Netherlands as a radio astronomy pioneer, at the very birth of the Dutch effort. He was, moreover, a trail blazer at the cutting edge of radio, not once but twice in his career. Without him it is unlikely that the 21 cm line would have been observed in the Netherlands in 1951, and arguably the H I mapping of the Milky Way under Jan Oort's leadership would have taken place much later, if at all. Radio astronomy observing itself might well have been compromised by interference had it not been for De Voogt's foresight.Anthonet Hugo de Voogt (1892–1969) built, while still a teenager, one of the very first amateur radio stations (call letters VO: · · · –/– – –) in Holland, earned the radio‐telegrapher's diploma during his student days, and was intimately involved in the foundation of the Dutch Society for Radio‐Telegraphy in 1916. Until the 1920s, he was very active in amateur radio and astronomy circles. Trained in electrical engineering at Delft, he joined the PTT (Post Office) as a telegraph engineer in 1919, worked his way through the ranks to become head of the telephone district of Breda in 1939, and was promoted to head the PTT Radio Service just days after the end of the war. As his department was responsible for overseas radio communication, he initiated a research effort to study radio propagation in the ionosphere and the effects of solar activity. To this end, he rescued a number of Würzburg‐Riese 7.5‐m radar antennas abandoned at the end of the war, made one available for Jan Oort's H I work, and launched a series of radio astronomical initiatives. His group also built a number of antennas, monitored solar emission, and participated in the International Geophysical Year (1957–1958). (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The search for the elusive Zeeman effect in HI
Authors: Davies R.D. 
Published: May 2007

AbstractThe paper describes the early endeavours by radioastronomers to detect the weak signature of the Zeeman effect in interstellar neutral hydrogen clouds in an effort to measure the Galactic magnetic field strength. The search is set in the context of the neutral hydrogen programme at Jodrell Bank. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Early Cambridge radio astronomy
Authors: Smith F.G. 
Published: May 2007

AbstractRadio astronomy started in Cambridge immediately after the hostilities of the World War II have ceased. Martin Ryle was the inspiring leader of a small group that started to develop interferometry techniques at the Cavendish Laboratory. From this development came the numerous Cambridge radio source surveys culminating in the Nobel prize awarded to Martin Ryle for invention of aperture synthesis. The history of this early development is the subject of the present paper. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The beginnings of decameter radio astronomy: pioneering works of Semen Ya. Braude and his followers in Ukraine
Authors: Vavilova I.B. , Konovalenko A.A. , Megn A.V. 
Published: May 2007

AbstractS.Ya. Braude (1911–2003) was the well‐known radio astronomer, one of the founders of low‐frequency astronomical research in the world, in particular in the former Soviet Union. He began to work in this field of science in 1957, in Kharkiv city (Ukraine), from the design and manufacturing small decameter interferometer ID‐1 and ID‐2. Since that time Braude and his team have developed more sophisticated radio decameter telescopes as UTR‐1 and UTR‐2 (the largest in the world till now) as well as the first decameter VLBI network URAN. They have obtained some important pioneering results about low‐frequency radio emission of objects in our Solar system, Galaxy and Metagalaxy by means of these telescopes. In this paper the key events of early history of decameter radio astronomy research in the former USSR are mentioned with emphasizing the role of S. Braude. For the period of 1957–1962, the quotations of Braude's Personal Diary (2003) are first laying open to the public. The most important results obtained by S.Ya. Braude and his followers as well as perspectives of decameter radio astronomy in Ukraine and in the world are highlighted briefly. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Early VLBI in the USSR
Authors: Matveenko L.I. 
Published: May 2007

AbstractThis article gives story of interferometer with independent elements (Very Long Baseline Interferometer) in Russia. At the end of February 1962 the author discussed with G.Ya. Gus'kov, DSN Station, Evpatorija a new type of radio interferometer and proposed an experiment between two DSN stations. In September 1962 he reported the new method and proposed a VLBI experiment at seminar of Radio Astronomical Laboratory, Pushino, and then at a seminar of Astronomical Institute GAISH which recommended to take out a Patent. In December GAISH sent documents to the Patent Bureau. In summer 1963 the author discussed with B. Lovell in Evpatorija the VLBI method of and we signed memorandum an Ev‐JB experiment at λ = 32 cm. In December 1963 the Patent Bureau permitted publication, and the paper was sent to Radiofizika. Really VLBI in the USSR began with the proposal of M. Cohen and K. Kellermann, February 1968, to do an experiment between 22‐m antenna Pushino and 43‐m Green Bank. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Fifty years of the Stockert Radio Telescope and what came afterwards
Authors: Wielebinski R. 
Published: May 2007

AbstractThe Stockert radio telescope was inaugurated 50 years ago. It is the beginning of German radio astronomy after the World War II. The 25‐m dish was for a short time the largest radio telescope in the world. It certainly was the most precise radio telescope for many years. The Bonn University Observatory was the starting base for the future Max‐Planck‐Institut für Radioastronomie with its 100‐m Effelsberg radio telescope. The early years of German radio astronomy and what came afterwards is the subject of this contribution. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Dwingeloo – the golden radio telescope
Authors: van Woerden H. , Strom R.G. 
Published: May 2007

AbstractThe Dwingeloo 25‐m telesope, inaugurated in 1956, has played a major role in research for half a century. We trace its history back to its conception in 1944, and summarize its main achievements. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Oral vaccines: new needs, new possibilities
Authors: Aziz Mohd Azhar , Midha Shuchi , Waheed Syed Mohsin , Bhatnagar Rakesh 
Published: May 2007

AbstractVaccination is an important tool for handling healthcare programs both in developed and developing countries. The current global scenario calls for a more‐efficacious, acceptable, cost‐effective and reliable method of immunization for many fatal diseases. It is hoped that the adoption of oral vaccines will help to provide an effective vaccination strategy, especially in developing countries. Mucosal immunity generated by oral vaccines can serve as a strong first line of defense against most of the pathogens infecting through the mucosal lining. Advances in elucidating the mechanism of action of oral vaccines will facilitate the design of more effective, new generation vaccines. There are promising developments in the use of different agents to effectively deliver the vaccine candidate. It is hoped that ongoing research may be able to set another cardinal point, after polio vaccine, in eradicating infectious diseases. BioEssays 29:591–604, 2007. © 2007 Wiley Periodicals, Inc.
Dynamic mutations as digital genetic modulators of brain development, function and dysfunction
Authors: Nithianantharajah Jess , Hannan Anthony J. 
Published: May 2007

AbstractA substantial portion of the human genome has been found to consist of simple sequence repeats, including microsatellites and minisatellites. Microsatellites, tandem repeats of 1–6 nucleotides, form the template for dynamic mutations, which involve heritable changes in the lengths of repeat sequences. In recent years, a large number of human disorders have been found to be caused by dynamic mutations, the most common of which are trinucleotide repeat expansion diseases. Dynamic mutations are common to numerous nervous system disorders, including Huntington's disease, various spinocerebellar ataxias, fragile X syndrome, fragile X tremor/ataxia syndrome, Friedreich ataxia and other neurodegenerative disorders. The involvement of dynamic mutations in brain disorders will be reviewed, with a focus on the large group caused by CAG/glutamine repeat expansions. We will also outline a proposed role of tandem repeat polymorphisms (TRPs), with unique ‘digital’ genetic distributions, in modulating brain development and normal function, so as to generate additional mutational diversity upon which natural selection may act. BioEssays 29:525–535, 2007. © 2007 Wiley Periodicals, Inc.
Early mouse embryo development: could epigenetics influence cell fate determination?
Authors: Henckel Amandine , Tóth Szabolcs , Arnaud Philippe 
Published: May 2007

AbstractIt is generally assumed that the developmental program of embryogenesis relies on epigenetic mechanisms. However, a mechanistic link between epigenetic marks and cell fate decisions had not been established so far. In a recent article, Torres‐Padilla and colleagues1 show that epigenetic information and, more precisely, histone arginine methylation mediated by CARM1 could contribute to cell fate decisions in the mouse 4‐cell‐stage embryo. It provides the first indications that global epigenetic information influences allocation of pluripotent cells toward the first cell lineages. BioEssays 29:520–524, 2007. © 2007 Wiley Periodicals, Inc.
Increased serum lipid peroxides initiate atherogenesis
Authors: Yagi Kunio 
Published: May 2007

AbstractThe development of a reliable and relatively simple micro‐assay for lipid peroxides in serum or plasma has made it possible to conduct clinical surveys of lipid peroxide levels in man. From many studies made in Japan, those suggesting a relationship between the elevation of lipid peroxide level plasma serum and the occurrence of vascular disorders are discussed here.The data described in this paper show that the elevation of the serum lipid peroxide level over the normal value is a direct cause of the initiation of atherogenesis. Therefore, any factor bringing about the elevation of serum lipid peroxide levels, such as irradiation, would be an indirect cause of atherogenesis. In fact, irradiation is known to provoke this disorder and to elevate serum lipid peroxide levels.
Seasonal Variation of the Chemical Constituents of the Essential Oil of Santolina etrusca from Italy
Authors: Flamini Guido , Cioni Pier Luigi 
Published: May 2007

AbstractThe seasonal variation of the essential oil, in terms of both yield and composition, of a population of Santolina etrusca (Asteraceae) is reported in detail for different aerial parts, including sterile branches, fertile branches, and capitula. The yields generally increased from November to June, and then decreased in August and September. The main constituents of the sterile branches were 1,8‐cineole and viridiflorol. The oil from fertile branches was characterized by myrcene as principal compound, whereas the essential oil obtained from the capitula contained germacrene D as the main constituent. Several compounds, as identified by GC and GC/MS, were found to prevail during the cold season.
Possible Molecular Evolution of Biomembranes: from Single‐Chain to Double‐Chain Lipids
Authors: Gotoh Mari , Sugawara Ayae , Akiyoshi Kazunari , Matsumoto Isamu , Ourisson Guy , Nakatani Yoichi 
Published: May 2007

AbstractWe have studied a possible evolution process permitting a ‘primitive’ membrane to evolve towards a membrane structure with an outer wall, similar to that of bacteria. We have investigated whether a polysaccharide bearing hydrophobic phytyl or cholesteryl chains coats giant vesicles made of single‐ or double‐chain lipids. Phytyl‐pullulan 5b was found to bind to the surface of vesicles made of either single‐ or double‐chain lipids. In contrast, cholesteryl‐pullulan 5a only coated the surface of vesicles made of double‐chain lipids. These results indicate that there must be a close match between the size and shape of membrane constituents and the hydrophobic molecules to be inserted. This process could, thus, provide a selection mechanism of lipid‐membrane constituents during the course of biomembrane evolution.The presence of the above ‘hydrophobized’ polysaccharides on the surface of different giant vesicles was identified by lectin binding. Both concanavalin A and annexin V were shown by fluorescence microscopy to bind spontaneously to vesicles made of double‐chain lipids. Our experiments exemplify that self‐organization of amphiphiles into closed vesicles in aqueous solution automatically leads to the coating of vesicles by ‘hydrophobized’ polysaccharides, which then permit lectin binding. This is a possible mechanism for the evolution of primitive membranes towards ‘proto‐cells’.
Distribution of Phenolic Compounds in Middleeuropean Taxa of the Achillea millefolium L. Aggregate
Authors: Benedek Birgit , Gjoncaj Noela , Saukel Johannes , Kopp Brigitte 
Published: May 2007

AbstractAchillea millefolium L. s.l. is a cytogenetically, morphologically, and chemically polymorphic aggregate. Besides the sesquiterpenes that possess chemotaxonomic relevance and mediate the antiphlogistic activity, the plant contains phenolic compounds such as dicaffeoylquinic acids and flavonoids causing choleretic and spasmolytic effects. To evaluate their contribution to the chemotaxonomy of European taxa of the A. millefolium group, we developed a SPE‐HPLC/UV method that allows quantification of the phenolic constituents in the different taxa. The investigated species displayed differences in the quantitative and qualitative composition of phenolic acids and flavonoids. Hence, they seem to be of chemotaxonomic significance, especially for the distinction of the diploid taxa. Combining the obtained results with the data of the sesquiterpene analyses gives a comprehensive insight into the distribution of those pharmacologically relevant plant constituents in the A. millefolium group.
Starch Degradation by Glucoamylase Glm from Saccharomycopsis fibuligera IFO 0111 in the Presence and Absence of a Commercial Pullulanase
Authors: Valachová Katarína , Horváthová Viera 
Published: May 2007

AbstractThis study describes the course of enzymatic hydrolysis of the native corn starches Maritena 100 and Maritena 300. Hydrolyses were carried out with glucoamylase Glm produced by Saccharomycopsis fibuligera IFO 0111, which degrades also native starch, with the purpose to substitute a two‐step hydrolysis (amylase followed by glucoamylase) by a one‐step process (glucoamylase only). Hydrolysis generally became more effective by adding the pullulanase Promozyme D, which cleaves α‐1,6‐glycosidic bonds more effectively than glucoamylase Glm does. The time course (kinetics) of hydrolysis was followed by determination of the glucose concentration and calculation of dextrose equivalents.
Cytotoxic and Apoptosis‐Inducing Properties of Auriculoside A in Tumor Cells
Authors: Zhang Rusong , Liu Yulan , Wang Yiqi , Ye Yiping , Li Xiaoyu 
Published: May 2007

AbstractThe C21‐steroidal glycoside auriculoside A (1), recently isolated from the roots of Cynanchum auriculatum, was found to inhibit the growth of several human tumor cell lines and to induce apoptosis in human breast cancer (MCF‐7) cells. Compound 1 was evaluated for its in vitro cytotoxicity against MCF‐7, HO‐8910, and Bel‐7402 cells, and for its in vivo antitumor effects on implanted sarcoma‐180 (S180) tumors in mice. It showed significant, concentration‐dependent inhibition of the cancer cells, both in vitro and in vivo. MCF‐7 Cells exposed to 1 displayed typical morphological apoptosis characteristics such as cytoplasm contraction and nuclear‐chromatin condensation. Flow‐cytometric analysis showed that the MCF‐7 cell cycle was arrested at the G0/G1 phase. When treated with 40 μg/ml of 1 for 24, 48, and 72 h, respectively, the apoptotic rates of the cells were ca. 5, 8, and 18.5%, respectively.
Rhizobialide: A New Stearolactone Produced by Mesorhizobium sp. CCNWGX022, a Rhizobial Endophyte from Glycyrrhiza uralensis
Authors: Wei Ge‐Hong , Yang Xue‐Ying , Zhang Ji‐Wen , Gao Jin‐Ming , Ma Yong‐Qing , Fu Yun‐Yun , Wang Pang 
Published: May 2007

AbstractThe endophytic strain Mesorhizobium sp. CCNWGX022 was isolated from licorice (Glycyrrhiza uralensis Fisch.) grown in the arid and semi‐arid regions of Northwest China. The new stearic acid derived γ‐lactone 1, named rhizobialide (=(5S)‐4,5‐dihydro‐5‐(8‐oxotetradecyl)furan‐2(3H)‐one), was isolated from the petroleum‐ether extract of the fermentation broth of this strain. The structure of 1 was elucidated on the basis of spectroscopic and mass‐spectrometric analysis. This is the first report of this type of compound from rhizobia.
Secondary Metabolites from Endophytic Streptomyces sp. Lz531
Authors: Zhao Pei‐Ji , Wang Hao‐Xin , Li Guo‐Hong , Li Hua‐Dong , Liu Jin , Shen Yue‐Mao 
Published: May 2007

AbstractFrom the branch tissue of Maytenus hookeri, the endophytic strain Lz531 was isolated, and determined to belong to Streptomyces, according to its 16S rRNA sequence. From the extracts of the fermentation broth of Streptomyces sp. Lz531, two new and four known compounds were isolated. The two new compounds were identified as cyclo(L‐Pro‐L‐Val‐L‐Val) (1) and 13‐methyl‐N‐(2‐phenylethyl)tetradecanamide (2).
Variability of the Needle Essential Oils of Pinus heldreichii from Different Populations in Montenegro and Serbia
Authors: Nikolić Biljana , Ristić Mihailo , Bojović Srdjan , Marin Petar D. 
Published: May 2007

AbstractThe essential‐oil compositions of Pinus heldreichii Christ. from Montenegro and Serbia are reported at the population level. Whitebark pine is a sub‐endemic high‐mountain Balkan pine relict of an anthropogenically reduced area, with large morphological diversity and insufficiently clear taxonomic position. In the pine‐needle terpene profile from three populations from Montenegro, and one from Serbia, 101 compounds were detected, 72 of which could be identified (Table 3). The dominant constituents are limonene (26.3%), α‐pinene (17.5%), germacrene D (13.5%), and β‐caryophyllene (10.4%), comprising ca. 67.7% of the essential oil. Medium‐to‐high contents (0.5–10%) of the following 16 additional components were found: β‐pinene, β‐myrcene, α‐humulene, δ‐cadinene, α‐muurolene, (E)‐hex‐2‐enal, β‐gurjunene, γ‐muurolene, isopimarol, camphene, γ‐cadinene, aromadendrene, β‐bisabolene, trans‐β‐farnesene, α‐cadinene, and (Z)‐hex‐3‐en‐1‐ol. The similarity of the populations and the within‐population variability was visualized by principle‐component analysis (PCA) of eleven selected terpenes in 97 tree samples. Cluster and genetic analyses suggest closest connection between the two spatially most‐distant populations I (Montenegro) and IV (Serbia). Based on the profile of the main sesquiterpene components, the studied populations from Montenegro and Serbia are more similar to the populations from Greece and the Central Balkan peninsula (Bosnia and Serbia–Kosovo) than to those on the furthest eastern margin of their natural range (Bulgaria).
Three New Sesquiterpenoids from the Aerial Parts of Homalomena occulta
Authors: Wang Yi‐Fen , Wang Xian‐You , Lai Guo‐Fang , Lu Chun‐Hua , Luo Shi‐De 
Published: May 2007

AbstractThree new eudesmane‐type sesquiterpenoids, compounds 1–3, and eight known constituents, including mucrolidin (4), 1β,4β,7α‐trihydroxyeudesmane (5), 1β,4β,6β,11‐tetrahydroxyeudesmane (6), oplodiol (7), bullatantriol (8), acetylbullatantriol (9), homalomenol (10), and maristeminol (11), were isolated from the aerial parts of Homalomena occulta. Their structures were determined by interpretation of spectroscopic and mass‐spectrometric data, and their antimicrobial activities toward six different bacterial strains were tested. Most of the compounds showed weak antibacterial activities in an agar‐diffusion assay.
Synthesis, Cytotoxicity, and Antitumor Activity of Lantadene‐A Congeners
Authors: Sharma Manu , Sharma Pritam Dev , Bansal Mohinder Pal , Singh Jaswant 
Published: May 2007

AbstractFive new derivatives of the pentacyclic triterpenoid lantadene A (=22β‐angeloyloxy‐3‐oxoolean‐12‐en‐28‐oic acid; 1) from the leaves of Lantana camara L. were synthesized, characterized, and screened for their cytotoxicities against four human cancer cell lines. The three most‐potent compounds, i.e., 1, 4, and 6, with IC50 values in the range of ca. 20–29 μM, were further studied for their in vivo tumor‐inhibitory potential upon oral administration in two‐stage squamous cell carcinogenesis, using female Swiss albino mice, papilloma being induced by 7,12‐dimethylbenz[a]anthracene (DMBA), and promoted by 12‐O‐tetradecanoylphorbol‐13‐acetate (TPA). The results are discussed in terms of structure–activity relationship.
A Major Triterpenoid Saponin from Gypsophila oldhamiana
Authors: Bai Hong , Zhong Ying , Xie Yan‐Ying , Wang Yuan‐Shu , Liu Lu , Zhou Ling , Wang Ju , Mu Yan‐Ling , Zuo Chun‐Xu 
Published: May 2007

AbstractA new saponin, gypoldoside A (1), was isolated from the roots of Gypsophila oldhamiana. On the basis of in‐depth NMR‐spectroscopic and mass‐spectrometric analysis, in combination with chemical evidence, its structure was established as 3‐O‐{β‐D‐galactopyranosyl‐(1→2)‐[β‐D‐xylopyranosyl‐(1→3)]‐β‐D‐glucuronopyranosyl}quillaic acid 28‐[α‐L‐arabinopyranosyl‐(1→2)‐α‐L‐arabinopyranosyl‐(1→3)‐β‐D‐xylopyranosyl‐(1→4)‐α‐L‐rhamnopyranosyl‐(1→2)‐β‐D‐fucopyranosyl] ester. Compound 1 was found to be highly active against three different human cancer cell lines, with IC50 values in the low micromolar range.
Dibenzocyclooctane Lignans from the Stems of Kadsura induta and Their Antiviral Effect on Hepatitis B Virus
Authors: Ma Wenhui , Ma Xiaolin , Huang Hai , Zhou Pei , Chen Daofeng 
Published: May 2007

AbstractTwo new dibenzocyclooctane lignans, kadsurindutins A (1) and B (2), were isolated from the stems of Kadsura induta, together with the known, structurally related lignans schisantherin L (3), schisantherin P (4), kadsulignan L (5), and neokadsuranin (6). Their structures and configurations were elucidated by spectroscopic methods (UV, ORD, CD, IR, 1D‐ and 2D‐NMR) in combination with mass‐spectrometric (HR‐MS) techniques. Compounds 1, 5, and 6 showed in vitro antiviral effects on hepatitis B virus.
Synthesis and Antitumor Evaluation of Benzopsoralen Analogues
Authors: Oliveira Ana M. A. G. , Oliveira‐Campos Ana M. F. , Rodrigues Lígia M. , Raposo M. Manuela M. , Machado Antonio E. H. , Nascimento M. São José , Nazareth N. , Pinto Madalena 
Published: May 2007

AbstractThe synthesis of five new tetracyclic benzopsoralen analogues, compounds 2–6, with 9H‐xanthen‐9‐one or 9H‐carbazole frameworks, is described. Their inhibitory effects on the growth of three human tumor cell lines (MCF‐7, SF‐268, and NCI‐460) were evaluated, and discussed in terms of structure–activity relationship, taking into account both geometric and electronic features. Generally, the angular compounds showed significant biological activities, but the arrangement of functional groups also contributed to the overall activity.