bluuebunny/crossref_metadata_2025 huggingface dataset:
Stamen dimorphism in Rhododendron ferrugineum (Ericaceae): development and function
Authors: Escaravage Nathalie , Flubacker Elisabeth , Pornon André , Doche Bernard , Till‐Bottraud Irène
Published: February 2007

The function of stamen dimorphism in the breeding system of the alpine shrub Rhododendron ferrugineum was studied in two populations in the French Alps. This species has pentameric flowers with two whorls of stamens: an inner whorl of five long stamens and an outer whorl of short stamens. We studied the development of stamens from buds to mature flowers (measurement of the filament, anther, and style lengths at five successive phenological stages) and compared the size and position of reproductive organs at maturity in control and partially emasculated flowers (removal of long‐level stamens) to determine whether the presence of long‐level stamens constitutes a constraint for the development of the short‐level ones. Stamen dimorphism can be observed early in stamen development, from the bud stage of the year prior to flowering. At this early stage, meiosis had already occurred. Emasculation of the long‐level stamens induced the short‐level ones to grow longer than in normal conditions. We also performed seven pollination treatments on ten randomly chosen individuals in each population, and the number of seeds following each treatment was recorded. Results from these treatments showed that R. ferrugineum produced spontaneous selfed seeds in the absence of pollinators. However, no seed was produced when short‐level stamens were emasculated and pollinators excluded, suggesting that long‐level stamens are not responsible for selfing in the absence of pollinators and that reproductive assurance is promoted by short‐level stamens.
Phylogenetic analysis of tribe Salsoleae (Chenopodiaceae) based on ribosomal ITS sequences: implications for the evolution of photosynthesis types
Authors: Pyankov Vladimir I. , Artyusheva Elena G. , Edwards Gerald E. , Black Clanton C. , Soltis Pamela S.
Published: February 2007

Diversity in photosynthetic pathways in the angiosperm family Chenopodiaceae is expressed in both biochemical and anatomical characters. To understand the evolution of photosynthetic diversity, we reconstructed the phylogeny of representative species of tribe Salsoleae of subfamily Salsoloideae, a group that exhibits in microcosm the patterns of photosynthetic variation present in the family as a whole, and examined the distribution of photosynthetic characters on the resulting phylogenetic tree. Phylogenetic relationships were inferred from parsimony analysis of nucleotide sequences of the internal transcribed spacer regions (ITS) of the 18S–26S nuclear ribosomal DNA of 34 species of Salsola and related genera (Halothamnus, Climacoptera, Girgensohnia, Halocharis, and Haloxylon) and representative outgroups from tribes Camphorosmeae (Camphorosma lessingii, Kochia prostrata, and K. scoparia) and Atripliceae (Atriplex spongiosa). A highly resolved strict consensus tree largely agrees with photosynthetic type and anatomy of leaves and cotyledons. The sequence data provide strong support for the origin and evolution of two main lineages of plants in tribe Salsoleae, with NAD‐ME and NADP‐ME C4 photosynthesis, respectively. These groups have different C4 photosynthetic types in leaves and different structural and photosynthetic characteristics in cotyledons. Phylogenetic relationships inferred from ITS sequences generally agree with classifications based on morphological data, but deviations from the existing taxonomy were also observed. The NAD‐ME C4 lineage contains species classified in sections Caroxylon, Malpigipila, Cardiandra, Belanthera, and Coccosalsola, and the NADP‐ME lineage comprises species from sections Coccosalsola and Salsola. Reconstruction of photosynthetic characters on the ITS phylogeny indicates separate NAD‐ME and NADP‐ME lineages and suggests two reversions to C3 photosynthesis. Reconstruction of geographic distributions suggests Salsoleae originated and diversified in central Asia and subsequently dispersed to Africa, Europe, and Mongolia. Inferred patterns and processes of photosynthetic evolution in Salsoleae should further our understanding of biochemical and anatomical evolution in Chenopodiaceae as a whole.
Seed coat morphology and its systematic implications in Cyanea and other genera of Lobelioideae (Campanulaceae)
Authors: Buss Craig C. , Lammers Thomas G. , Wise Robert R.
Published: February 2007

Recent surveys of seed coat morphology in Lobelioideae (Campanulaceae) have demonstrated the systematic utility of such data in the subfamily and led to a revision of the supraspecific classification of Lobelia. Expanding upon these studies, we examined via scanning electron microscopy 41 seed accessions, emphasizing lobelioid genera in which only one or no species had been examined. Most conformed to previously described testal patterns. However, five species of the endemic Hawaiian genus Cyanea, comprising the molecularly defined Hardyi Clade, had a unique testal pattern (here termed Type F), characterized by laterally compressed, almost linear, areoles with rounded, knob‐like protuberances on the radial walls at opposite ends. This offered a convenient synapomorphy for recognition of a clade originally defined on a molecular basis. A second unique testal pattern was found in the related Hawaiian endemics Brighamia and Delissea, thus supporting their close relationship. In this type (here termed Type G), the seed coat is irregularly wrinkled (rugose), creating broad, rounded ridges that run more‐or‐less perpendicular to the long axis of the seed and thus to the long axis of the testal cells. Seed coat morphology also supported the monophyly of all 124 species of Hawaiian Lobelioideae and their probable derivation from Asian species of Lobelia subg. Tupa. Additional studies supported close relationships between (1) the neotropical genera Centropogon and Siphocampylus; (2) the western American genera Legenere and Downingia; and (3) Jamaican Hippobroma and Lobelia sect. Tylomium, a group endemic to the West Indies.
Population genetic study in the Balearic endemic plant species Digitalis minor (Scrophulariaceae) using RAPD markers
Authors: Sales Ester , Nebauer Sergio G. , Mus Maurici , Segura Juan
Published: February 2007

Digitalis minor (Scrophulariaceae) is a cardenolide‐producing plant endemic to the eastern Balearic Islands (Mallorca, Menorca, and Cabrera) that occurs in two morphologically distinct varieties: D. minor var. minor (pubescent) and D. minor var. palaui (glabrous). Levels and patterns of genetic diversity in 162 individuals from 17 D. minor populations across the entire geographic range were assessed using random amplified polymorphic DNA (RAPD) markers. Comigrating RAPD fragments tested were found to be homologous by Southern hybridization in both var. minor and var. palaui. To avoid bias in parameter estimation, analyses of population genetic structure were restricted to those RAPD bands that fulfilled the 3/N criterion (observed frequencies were less than 1 − [3/N] in each population) either among or within each island. Analyses of molecular variance (AMOVAs) with distances among individuals corrected for the dominant nature of RAPD (genotypic analysis) showed low values (1.57–17.55%) of between‐population variability, indicating a relatively restricted population differentiation as expected for an outcrossing species such as D. minor. Nested AMOVAs demonstrated, however, a not significant partitioning of genetic diversity among Mallorca, Menorca, and Cabrera islands. Estimates of the Wright, Weir, and Cockerham and the Lynch and Milligan FST from null allele frequencies corroborated AMOVA partitioning and provided evidence for population differentiation in D. minor. Our RAPD data did not show significant differences between pubescent and glabrous populations of D. minor, suggesting a failure to find a correlation between the RAPD loci and this morphological trait.
Multiple origins of sequestrate fungi related to Cortinarius (Cortinariaceae)
Authors: Peintner Ursula , Bougher Neale L. , Castellano Michael A. , Moncalvo Jean‐Marc , Moser Meinhard M. , Trappe James M. , Vilgalys Rytas
Published: February 2007

The aim of the present study was to investigate the phylogeny and evolution of sequestrate fungi (with gastroid or partially exposed basidiomes) in relation to their gilled relatives from the Cortinariaceae (Basidiomycetes). Phylogenetic analyses of 151 ITS sequences from 77 gilled species and 37 sequestrate taxa were performed using maximum parsimony and maximum likelihood methods. Results show that sequestrate basidiome forms occur in all three major ectomycorrhizal lineages of Cortinariaceae: the clades Cortinarius, Hebeloma/Hymenogaster/Naucoria, and Descolea. However, these forms do not appear within the saprobic outgroup Gymnopilus, indicating multiple origins of sequestrate forms from ectomycorrhizal ancestors. Additionally, within the Cortinarius clade sequestrate forms have multiple origins: emergent Cortinarius spp., Thaxterogaster, Quadrispora, Protoglossum, and two Hymenogaster spp. (H. remyi, H. sublilacinus) share common ancestors with Cortinarius spp., but these sequestrate genera are not closely related to each other (with exception of Thaxterogaster and Quadrispora). Hymenogaster sensu stricto, Setchelliogaster, and Descomyces were placed in the two other major clades. Thus, sequestrate taxa evolved independently many times within brown‐spored Agaricales. Furthermore, emergent, secotioid, and gastroid forms have evolved independently from each other, and so are not necessarily intermediate forms. After their establishment, these apparently morphologically stable taxa show a tendency to radiate.
Effects of mycorrhizae on growth and demography of tallgrass prairie forbs
Authors: Wilson Gail W. T. , Hartnett David C. , Smith Melinda D. , Kobbeman Kerri
Published: February 2007

The effects of arbuscular mycorrhizal (AM) symbiosis on ramet and genet densities, vegetative growth rates, and flowering of three forb species were studied in native tallgrass prairie in northeastern Kansas. Mycorrhizal activity was experimentally suppressed for six growing seasons on replicate plots in an annually burned and an infrequently burned watershed with the fungicide benomyl. Benomyl reduced mycorrhizal root colonization to an average of 4.2%, approximately a two‐thirds reduction relative to controls (13.7% colonization). Mycorrhizae influenced the population structure of these forbs. Although mycorrhizal suppression had no long‐term effect on genet densities and no effect on ramet survivorship throughout the growing season, the number of ramets per individual was significantly increased such that ramet densities of all three species were approximately doubled in response to long‐term mycorrhizal suppression. Effects of mycorrhizae on ramet growth and reproduction varied among species. Ramet growth rates, biomass, and flowering of Salvia azurea were greater in plots with active mycorrhizal symbiosis, whereas mycorrhizae reduced ramet growth rates and biomass of Artemesia ludoviciana. Aster sericeus ramet growth rates and biomass were unaffected by the fungicide applications, but its flowering was reduced.

The pattern of responses of these three species to mycorrhizae differed considerably between the two sites of contrasting fire regime, indicating that the interaction of fire‐induced shifts in resource availability and mycorrhizal symbiosis together modulates plant responses and the intensity and patterns of interspecific competition between and among tallgrass prairie grass and forb species. Further, the results indicate that effects of mycorrhizae on community structure are a result of interspecific differences in the balance between direct positive effects of the symbiosis on host plant performance and indirect negative effects mediated through altered competitive interactions.
Making the Colonial State Work for You: The Modern Beginnings of the Ancient Kumbh Mela in Allahabad
Authors: Maclean Kama
Published: February 2007

It is widely believed that the Allahabad Kumbh Mela is an ancient religious festival or that it is “ageless”, that its roots lie obscured in time immemorial. Editorials and articles in the press atmelatime (every twelve years) lyrically emphasize the continuity of the pilgrimage throughout India's past, find inspiration in its durability and changeless character, and marvel at the anachronism of an ancient festival thriving in the modern world (“The Kumbh Mela”,Pioneer, 17 February 1918; “Editorial”,Leader, 16 January 1942; “Pilgrim's Process”,Times of India, 24 January 2001). There is no better example of this than the oft-quoted section of Jawaharlal Nehru's will and testament, in which the avowedly secular modernist explains his desire to have a portion of his ashes scattered at thetriveni sangam, the confluence of the Ganga and Yamuna Rivers and the site of the Kumbh in Allahabad:

I have been attached to the Ganga and the Jumna rivers ever since my childhood and, as I have grown older, this attachment has also grown. The Ganga, especially, is the river of India, beloved of her people. … She has been a symbol of India's age-long culture and civilization, ever-changing, ever-flowing, and yet ever the same Ganga. … And though I have discarded much of past tradition and custom, and am anxious that India should rid herself of all shackles that bind and constrain her and divide her people, and suppress vast numbers of them, and prevent the free development of the body and the spirit; though I seek all this, yet I do not wish to cut myself off from that past completely. I am proud of that great inheritance that it has been, and is, ours, and I am conscious that I too, like all of us, am a link in that unbroken chain which goes back to the dawn of history in the immemorial past of India. That chain I would not break, for I treasure it and seek inspiration from it.

(2000, 612–13)
Texas Mexicans and the Politics of Whiteness
Authors: Gross Ariela J.
Published: February 2007

These two fascinating articles seek to fill an important lacuna in the burgeoning literature on the legal construction of whiteness. While LatCrit theorists in the legal academy have urged civil rights scholars and race critics to transcend the “black-white paradigm” of U.S. race studies, the majority of legal histories of whiteness have focused on two sets of cases: trials in the southeastern United States in which local courts tried to draw the line between “white” and “negro”; and cases about immigration and naturalization in which Federal courts determined whether particular foreign immigrants were suitably “white” for citizenship. Likewise, although there have been several important social and cultural histories of Texas Mexicans and whiteness in the last fifteen years, they have not considered the legal realm. The time is ripe for attention to the legal history of Mexican Americans' civil rights struggles in Texas, especially as they illuminate the shifting racial identity of Mexican Americans in the Southwest.
Nomenclatural pitfalls in the protologue of Hypnum lycopodioides Brid. (Musci)
Authors: Ochyra Ryszard , Zijlstra Gea
Published: February 2007

The nomenclatural history of Hypnum lycopodioides Brid., a widespread European peatland moss that is currently known as Drepanocladus lycopodioides (Brid.) Warnst. or Pseudocalliergon lycopodioides (Brid.) Hedenäs, is presented. The placement of two neglected and poorly known names, "Hypnum rugosum Sm." and H. diastrophyllum Lam. & DC., in the protologue of H. lycopodioides created some nomenclatural pitfalls. It is shown that H. rugosum sensu Dickson (1801), Withering (1801), Smith (1804) and Smith & Sowerby (1811) are all isonyms of H. rugosum Hedw. [= Rhytidium rugosum (Hedw.) Kindb.] and they have no nomenclatural status. Hypnum diastrophyllum, a species described in 1805, is considered not to be definitely included in the concept of H. lycopodioides, but the latter name is strongly endangered by H. diastrophyllum, if both species are conspecific. Of several specimens cited in the protologue of H. diastrophyllum only one specimen originating from Sweden is available for typification, and it is here selected as lectotype. It makes H. diastrophyllum conspecific with Palustriella commutata (Hedw.) Ochyra, and this taxonomic conclusion saves the current usage of H. lycopodioides. The oldest synonyms and type specimens of H. lycopodioides are listed.
Parsimony analyses of mtSSU and nITS rDNA sequences reveal the natural relationships of the lichen families Physciaceae and Caliciaceae
Authors: Wedin Mats , Baloch Elisabeth , Grube Martin
Published: February 2007

The phylogenetic relationships of the lichenised families Caliciaceae and Physciaceae (Lecanorales, Ascomycota) are investigated with parsimony analyses of combined mtSSU and nITS rDNA sequences. Physciaceae include two well‐supported groups, which correspond to the informally recognised “Buellia ‐group” and “Physcia‐group”. The prototunicate, mazaedia‐forming representatives of Caliciaceae are derived from within Physciaceae, and fall within the “Buellia‐group”. Nomenclatural consequences of two different scenarios of changes in the present classification are discussed.
The Cardamine pratensis (Brassicaceae) group in the Iberian Peninsula: taxonomy, polyploidy and distribution
Authors: Lihová Judita , Tribsch Andreas , Marhold Karol
Published: February 2007

The Cardamine pratensis group is a taxonomically critical species complex with pronounced karyological and morphological variation. In the present study, representatives from the Iberian Peninsula have been investigated using karyological, morphometric and molecular (amplified fragment length polymorphism) analyses. As a result of this combined approach, three species are recognized in the area studied: C. pratensis s.str., C. crassifolia, and a herein newly described species, C. castellana. For C. pratensis s.str., consistent with the pattern known from other European regions, wide variation in chromosome numbers is revealed, consisting of diploid to heptaploid populations in northern and central parts of the Peninsula. Little morphological and genetic differentiation accompanies these cytotypes. Re‐evaluation of populations up to now ascribed to C. crassifolia reveal two separate taxa: (1) populations from the Eastern Pyrenees, representing typical C. crassifolia, and (2) those from central Iberian mountains treated as C. castellana. These two diploid taxa differ in several quantitative morphological characters, as well as in morphology of rhizome and basal parts of stem, and they are also distinct in AFLP markers, indicating strong genetic differentiation.
On the typification of two Mascarene Elaphoglossum (Lomariopsidaceae): E. heterolepis (Fée) T. Moore and E. tomentosum (Bory ex Willd.) H. Christ
Authors: Rouhan Germinal , Lorence David H.
Published: February 2007

This article deals with the lectotypification of Elaphoglossum tomentosum and E. heterolepis. Both names apply to species of leptosporangiate ferns from the Mascarene Islands. The typification of these names is clarified to establish their correct application for a revision of the Mascarene Elaphoglossum species.
Nominal extinction and the taxonomist’s responsibility: the example of Bromeliaceae in Brazil
Authors: Leme Elton M. C.
Published: February 2007

The destruction of the Brazilian Atlantic Forest is considered the world's most alarming conservation problem. The rudimentary knowledge of the thousands of species that inhabit such a fragmented biome highlights the importance of taxonomy as a basic tool for conservation. Bromeliaceae are one of the most striking elements of the Atlantic Forest and contribute significantly to biodiversity support capacity of the communities in which they live. This article utilizes the example of Bromeliaceae in Brazil to discuss the potential impact of misguided taxonomic and nomenclatural changes on the survival of species, and how it may affect biodiversity assessment. Nominal extinction is described as a phenomenon caused by errors in taxonomic decisions that involve mistaken designation of synonyms at the specific and infraspecific level. All taxonomic decisions that have the potential to create a negative impact on the environment should be widely discussed and anchored on the precautionary principal adopted by 1992 UN Conference on the Environment.
A reassessment of the taxonomy and nomenclature of Liatris borealis Nutt. ex J. McNab and Lacinaria scariosa var. novae-angliae Lunell (Asteraceae)
Authors: Gandhi Kanchi N. , Young Stephen M. , Somers Paul
Published: February 2007

A reassessment of the taxonomy of Liatris borealis Nutt. ex J. McNab suggests that it is not conspecific with L. novae-angliae, but is a synonym of L. scariosa L. var. scariosa. Three varieties are recognized within the L. scariosa complex; the varietal name L. borealis var. novae-angliae, not hitherto validly published, is validly published here.
Lectotypification of twenty names of taxa referable to Tortula Hedw. (Pottiaceae, Bryophyta)
Authors: Cano María J. , Gallego M. Teresa
Published: February 2007

Lectotypes for twenty names currently included in Tortula Hedw. are designated here. Tortula santorinensis Schiffn. is considered to be conspecific with T. solmsii (Schimp.) Limpr., of which it becomes a synonym, and T. eucalyptrata Lindb. conspecific with T. euryphylla R. H. Zander (≡ T. latifolia (Hedw.) Lindb., nom. illeg.), over which it has priority. In addition, the following infraspecific taxa, sometimes accepted in current literature, are not considered to be recognisable taxonomically, and are synonymized under the Tortula species involved: Desmatodon latifolius var. muticus (Brid.) Brid. (≡ Dicranum latifolium var. muticum Brid.) (= Tortula eucalyptrata), Tortula cuneifolia var. marginata M. Fleisch., T. muralis f. incana (Schimp.) Sapjegin (≡ Barbula muralis var. incana Schimp.), and T. revolvens var. obtusata Reimers.
A Visit to the Museum: Aleksandr Sokurov's Russian Ark and the Framing of the Eternal
Authors: Harte Tim
Published: February 2007

In this close analysis of Aleksandr Sokurov's 2002 film Russkii kovcheg (Russian ark), Tim Harte explores the interplay between the medium of painting and cinema in this unprecedented ninety-minute single-shot film set in the grand halls and galleries of the Hermitage Museum. As Harte argues, the film's unique premise and setting allow Sokurov to convey how the museum, its art and history, and subsequently cinema can affirm a nation's culture, transporting die past ever so evocatively into the present in order to sustain culture's vitality. Throughout Sokurov's ninety-minute single-shot fusion of Western art and Russian history, a continual emphasis on the image of the frame prevails, with the frame constituting an important artistic and metaphysical threshold for the filmmaker. Constandy moving through the ubiquitous frames, Sokurov establishes his own cinematic rendering of culture's eternal essence.
Totalitarianism: Racial Values vs. Religious Values:Clerical Opposition to Nazi Anti-Polish Racial Policy
Authors: Delaney John J.
Published: February 2007

Hitler's wars for living space sent millions of Germans abroad and aggravated a severe labor shortage at home. German authorities recruited or forcibly transported up to seven million foreign workers to the Reich from 1939 to 1945. A great many of these civilian workers, POWs, and slave laborers came from Poland, the Ukraine, and western areas of the Soviet Union, that is, homelands the Nazi regime stigmatized as particularly “inferior.” Nazi racial thinking and wartime security concerns produced an extensive set of discriminatory measures aimed at the subjugation and strict control of Slavs. Nazi edicts required Poles and so-called Eastern Workers (Ostarbeiter) to wear a purple “P” or “Ost” badge on their outer clothing. Restrictive measures limited allowable movement to their immediate area of residence and work. The regime also imposed a system akin to apartheid. Racial law thus prohibited unnecessary social contact between members of the so-called master race and their “racial inferiors.”
The Cross: Church Symbol and Contest in Nineteenth-Century America
Authors: Smith Ryan K.
Published: February 2007

In 1834 the rector of St. Mary's Episcopal Church in Burlington, New Jersey desired to place a cross atop his newly-refurbished sanctuary. No ordinary rector, George Washington Doane also served as the Episcopal bishop of New Jersey. Shortly after taking charge of St. Mary's in 1833, he and his vestry had decided to renovate their old church, and their ambitious new design featured a cruciform plan with Greek details, including a pediment adorned with lotus leaves and a tower “derived from that built at Athens… commonly called the Tower of the Winds.” But when Doane carried out the plans for “an enriched Greek Cross” to be mounted on the roof, the community stood aghast. A local Presbyterian minister chronicled the confrontation, and he began by asserting that most of St. Mary's vestrymen had originally approved the designs without “noticing the Crossat the time.” The project was thus completed, and to the vestry's “great surprise, as well as that of many in the community, of all ‘denominations’—lo! a Cross made quite a Catholic appearance on the apex of the pediment!” Controversy arose, “both in the Vestry and out of it,” and “after a very warm meeting, one of the Vestry shortly after declared that unless the Cross was taken down very soon, it should be pulled down.”
Chemical Composition of the Above-ground Biomass of Amaranthus cruentus and A. hypochondriacus
Authors: Písaříková B. , Peterka J. , Trčková M. , Moudrý J. , Zralý Z. , Herzig I.
Published: February 2007

Forty samples of dry above-ground biomass of two species and four varieties of Amaranthus cruentus (varieties Olpir, Amar 2 RR-R 150, and A 200 D) and A. hypochondriacus (variety No. 1008) were analyzed to determine their nutritional value during the experimental period covering five growth stages since inflorescence emergence till full ripening of grain from day 80 to day 120 of cultivation. The content of crude protein in the investigated amaranth varieties significantly decreased (from 158.2 ± 1.20 - 185.4 ± 2.33 to 103.8 ± 1.20 - 113.1 ± 0.01 g/kg) as well as did the crude ash content (from 169.9 ± 0.14 - 192.2 ± 0.42 to 129.7 ± 0.14 - 138.4 ± 0.21 g/kg). In contrast, the ether extract content significantly increased (from 12.2 ± 0.14 - 15.9 ± 0.28 to 28.0 ± 0.28 - 36.4 ± 0.14 g/kg) as well as crude fibre (from 144.9 ± 2.12 - 170.0 ± 3.68 to 183.6 ± 7.00 - 276.0 ± 1.20 g/kg), and gross-energy (from 16.6 ± 0.03 - 17.2 ± 0.07 to 18.1 ± 0.14 - 18.4 ± 0.01 MJ/kg) between days 80 and 120 of cultivation. The relatively high content of crude protein in the aboveground biomass in the period between days 80 and 90 of cultivation suggests that the plants could be used as a nutrient substitute for conventional forages.
Embedded control system for a four‐rotor UAV
Authors: Salazar‐Cruz S. , Escareño J. , Lara D. , Lozano R.
Published: February 2007

This paper describes the design of an embedded control system for a four‐rotor unmanned aerial vehicle (UAV) to perform hover flights. A dynamic model of the vehicle is presented using an Euler–Lagrange approach. A control strategy based on nested saturation is proposed. An embedded control system architecture is described for autonomous hover flight. The main components of the system are a microcontroller, an inertial measurement unit (IMU), a global positioning system (GPS) and infrared sensors. The Euler angles are computed using a data fusion algorithm. The experimental results show that the on‐board control system performs satisfactorily for autonomous hovering indoors. Copyright © 2007 John Wiley & Sons, Ltd.
Modeling extraction separation of Nd(III) and La(III) from nitrate media in hollow‐fiber modules
Authors: Juang Ruey‐Shin , Kao Hsiang‐Chien , Yen Pei‐Shin
Published: February 2007

The use of two microporous hollow‐fiber modules for simultaneous extraction and stripping of binary Nd(III) and La(III) from nitrate media with a kerosene solution of 2‐ethylhexylphosphonic acid mono‐2‐ethylhexyl ester (PC88A) to a HNO3 solution was investigated. Experiments were carried out at different feed pH values (2–6), total metal concentrations (2–24 g‐mol/m3), metal concentration ratios (0.25–4), and dimeric PC88A concentrations (17–137 g‐mol/m3). A kinetic model was presented that takes into account the resistances of diffusion in the aqueous stagnant layer, membrane pore, and organic stagnant layer as well as interfacial reactions. It was shown that the calculated time changes of the feed‐ and strip‐phase metal concentrations were in acceptable agreement with the measured data (standard deviation, 8%). The extraction process was dominated by membrane diffusion under the conditions studied, whereas the stripping process was primarily governed by combined membrane and aqueous strip‐layer diffusion. Effective separation of Nd(III) over La(III) by PC88A in such continuous NDSX process could be achieved, mainly by selective stripping, at high feed pH values or low organic PC88A concentrations. © 2007 American Institute of Chemical Engineers AIChE J, 2007
X‐linked NDUFA1 gene mutations associated with mitochondrial encephalomyopathy
Authors: Fernandez‐Moreira Daniel , Ugalde Cristina , Smeets Roel , Rodenburg Richard J. T. , Lopez‐Laso Eduardo , Ruiz‐Falco Maria L. , Briones Paz , Martin Miguel A. , Smeitink Jan A. M. , Arenas Joaquín
Published: February 2007

Objective

Mitochondrial complex I deficiency is the commonest diagnosed respiratory chain defect, being genetically heterogeneous. The male preponderance of previous patient cohorts suggested an X‐linked underlying genetic defect. We investigated mutations in the X‐chromosomal complex I structural genes, NDUFA1 and NDUFB11, as a novel cause of mitochondrial encephalomyopathy.

Methods

We sequenced 12 nuclear genes and the mitochondrial DNA–encoded complex I genes in 26 patients with respiratory chain complex I defect. Novel mutations were confirmed by polymerase chain reaction restriction length polymorphism. Assembly/stability studies in fibroblasts were performed using two‐dimensional blue native gel electrophoresis.

Results

Two novel p.Gly8Arg and p.Arg37Ser hemizygous mutations in NDUFA1 were identified in two unrelated male patients presenting with Leigh's syndrome and with myoclonic epilepsy and developmental delay, respectively. Two‐dimensional blue native gel electrophoresis showed decreased levels of intact complex I with no accumulation of lower molecular weight subcomplexes, indicating that assembly, stability, or both are compromised.

Interpretation

Mutations in the X‐linked NDUFA1 gene result in complex I defect and encephalomyopathy. Assembly/stability analysis might give an explanation for the different clinical phenotypes and become useful for future diagnostic purposes. Ann Neurol 2007;61:73–83
Progressive gaa expansions in dorsal root ganglia of Friedreich's ataxia patients
Authors: De Biase Irene , Rasmussen Astrid , Endres Dan , Al‐Mahdawi Sahar , Monticelli Antonella , Cocozza Sergio , Pook Mark , Bidichandani Sanjay I.
Published: February 2007

Objective

Friedreich's ataxia patients are homozygous for expanded alleles of a GAA triplet‐repeat sequence in the FXN gene. Patients develop progressive ataxia due to primary neurodegeneration involving the dorsal root ganglia (DRGs). The selective neurodegeneration is due to the sensitivity of DRGs to frataxin deficiency; however, the progressive nature of the disease remains unexplained. Our objective was to test whether the expanded GAA triplet‐repeat sequence undergoes further expansion in DRGs as a possible mechanism underlying the progressive pathology seen in patients.

Methods

Small‐pool polymerase chain reaction analysis, a sensitive technique that allows the measurement of repeat length in individual FXN genes, was used to analyze somatic instability of the expanded GAA triplet‐repeat sequence in multiple tissues obtained from six autopsies of Friedreich's ataxia patients.

Results

DRGs showed a significantly greater frequency of large expansions (p < 0.001) and a relative paucity of large contractions compared with all other tissues. There was a significant age‐dependent increase in the frequency of large expansions in DRGs, which ranged from 0.5% at 17 years to 13.9% at 47 years (r = 0.78; p = 0.028).

Interpretation

Progressive pathology involving the DRGs is likely due to age‐dependent accumulation of large expansions of the GAA triplet‐repeat sequence. Thus, somatic instability of the expanded GAA triplet‐repeat sequence may contribute directly to disease pathogenesis and progression. Progressive repeat expansion in specific tissues is a common theme in the pathogenesis of triplet‐repeat diseases. Ann Neurol 2007;61:55–60
Catalysis by Ir(III), Rh(III) and Pd(II) metal ions in the oxidation of organic compounds with H2O2
Authors: Tandon Praveen K. , Gayatri  , Sahgal Sumita , Srivastava Manish , Singh Santosh B.
Published: February 2007

Catalytic activities of three transition metals, as iridium (III) chloride, rhodium (III) chloride and palladium (II) chloride, were compared in the oxidation of six aromatic aldehydes (benzaldehyde, p‐chloro benzaldehyde, p‐nitro benzaldehyde, m‐nitro benzaldehyde, p‐methoxy benzaldehyde and cinnamaldehyde), two hydrocarbons (viz. (anthracene and phenanthrene)) and one aromatic and one cyclic alcohol (cyclohexanol and benzyl alcohol) by 50% H2O2. The presence of traces (substrate: catalyst ratio equal to 1:62500 to 1:1961) of the chlorides of iridium(III), rhodium(III) and palladium(II) catalyze these oxidations, resulting in good to excellent yields. It was observed that in most of the cases palladium(II) chloride is the most efficient catalyst. Conditions for the highest and most economical yields were obtained. Deviation from the optimum conditions decreases the yields. Oxidation in aromatic aldehydes is selective at the aldehydeic group only and other groups remain unaffected. This new, simple and economical method, which is environmentally safe, also requires less time. Reactive species of catalysts, existing in the reaction mixture are also discussed. Copyright © 2007 John Wiley & Sons, Ltd.
Semiempirical studies on the interactions of dialkyldi(aquo)tin cations, [R2Sn(H2O)2]2+, with selected nucleotides
Authors: Cassús Eduardo P. , Machado Sergio P. , Wardell James L.
Published: February 2007

Semiempirical calculations have been carried out on the interactions of [R2Sn(H2O)2]2+, [R = H(CH2)n: n = 1–8], mainly with five nucleotides, 5′‐adenosine monophosphate (5′‐AMP), but also with guanosine 5′‐monophosphate (5′‐GMP), cytidine 5′‐monophosphate (5′‐CMP), uridine‐5′‐monophosphate (5′‐UMP) and inosine 5′‐monophosphate (5′‐IMP). The preferred sites of interaction were calculated to be the ribose O2 and O3 hydroxyl oxygens and/or the phosphate oxygens, with the nitrogen sites in the bases the least attractive to the tin compounds. This is in general agreement with experimental findings. Structures of the 1:1 coordination complexes vary from distorted tetrahedral, to distorted trigonal pyramidal to distorted octahedral geometries. Copyright © 2007 John Wiley & Sons, Ltd.
Structural studies on ruthenium(II) complexes used in interphase catalysis for the hydrogenation of ketones
Authors: Krishnan Venkata , Bertagnolli Helmut
Published: February 2007

Structural studies were performed on catalytically active ruthenium(II) complexes used in interphases, by means of XAFS spectroscopy. The EXAFS investigations indicate that the complexes retain their structural integrity when they are embedded on polysiloxane matrices to form stationary phase materials. The AXAFS studies reveal that the variations in the catalytic activity of the complexes with different ligands can be correlated to the differences in the electronic structure around the active ruthenium center. The EXAFS investigations show that, in asymmetric transfer hydrogenation reactions catalysed by ruthenium(II) complexes, the co‐catalyst plays a crucial role not only in enhancing the catalytic activity, but also in determining the structure of the intermediate species. Copyright © 2007 John Wiley & Sons, Ltd.
Synthesis, magnetic property and DNA cleavage behavior of a new dialkoxo‐bridged diiron(III) complex
Authors: Xu Jing‐Yuan , Tian Jin‐Lei , Bian He‐Dong , Yan Shi‐Ping , Liao Dai‐Zheng , Cheng Peng , Shen Pan‐Wen
Published: February 2007

A new dialkoxo‐bridged diiron(III) complex, [Fe2(BMA)2(CH3O)2Cl2]·2Cl·4CH3OH (1) [BMA = N,N‐bis(2‐benzimidazolylmethyl)amine], was synthesized and characterized by UV‐visible absorption and infrared spectra and magnetic susceptibilities. The complex crystallizes in the monoclinic system, space group P2(1)/n, a = 12.9659(19) Å, b = 10.0278(16) Å, c = 17.919(2) Å, β = 93.766(8)° , V = 2324.8(6) Å3, Z = 2, F(000) = 1036, Dc = 1.426 g cm−3, µ = 0.908 mm−1. According to X‐ray crystallographic studies, each Fe(III) ion lies in a highly distorted octahedral environment, and two Fe(III) ions are bridged by the methoxyl oxygens. Cryomagnetic analyses indicated a moderate antiferromagnetic interaction between the high‐spin Fe(III) ions, with J = − 27.05 cm−1. Moreover, the binding interaction of DNA with the diiron complex was investigated by spectroscopic and agarose gel electrophoretic methods, showing moderate cleavage activity on pBR322 plasmid DNA at physiological pH and temperature. Copyright © 2007 John Wiley & Sons, Ltd.
Therapeutic effect of urocortin on collagen‐induced arthritis by down‐regulation of inflammatory and Th1 responses and induction of regulatory T cells
Authors: Gonzalez‐Rey Elena , Chorny Alejo , Varela Nieves , O'Valle Francisco , Delgado Mario
Published: February 2007

Objective

To investigate the potential therapeutic action of the immunomodulatory neuropeptide urocortin (UCN) in an experimental model of rheumatoid arthritis (RA).

Methods

After disease onset, DBA/1J mice with collagen‐induced arthritis (CIA) were treated with UCN, and the incidence, severity (clinical score), and joint histopathology were evaluated. The inflammatory response was determined by measuring the levels of different mediators of inflammation (cytokines and chemokines) in the joints and sera. The Th1‐mediated autoreactive response was evaluated by determining the proliferative response and cytokine profile of draining lymph node cells stimulated with the autoantigen and by assaying the content of serum autoantibodies. The number of regulatory CD4+,CD25+ T cells and their capacity to suppress self‐reactive Th1 cells were determined in joints and lymph nodes.

Results

UCN treatment significantly reduced the incidence and severity of CIA, completely abrogating joint swelling and cartilage and bone destruction. The therapeutic effect of UCN was associated with a striking reduction of the 2 deleterious components of the disease: the Th1‐driven autoimmune response and the inflammatory response. UCN also induced the generation and/or activation of efficient interleukin‐10/transforming growth factor β1–producing Treg cells in arthritis with the capacity to suppress the autoreactive response and to restore immune tolerance, thus playing a pivotal role in the therapeutic effect of UCN.

Conclusion

Our findings provide a powerful rationale for assessing the efficacy of UCN as a novel multistep therapeutic approach to the treatment of RA in humans.
Electromagnetic Field Treatment of Nerve Crush Injury in a Rat Model: Effect of Signal Configuration on Functional Recovery
Authors: Walker Janet L. , Kryscio Richard , Smith Jennifer , Pilla Arthur , Sisken Betty F.
Published: February 2007

Electromagnetic fields (EMFs) have been demonstrated to enhance mammalian peripheral nerve regeneration in vitro and in vivo. Using an EMF signal shown to enhance neurite outgrowth in vitro, we tested this field in vivo using three different amplitudes. The rat sciatic nerve was crushed. Whole body exposure was performed for 4 h/day for 5 days in a 96‐turn solenoid coil controlled by a signal generator and power amplifier. The induced electric field at the target tissue consisted of a bipolar rectangular pulse, having 1 and 0.3 ms durations in each polarity, respectively. Pulse repetition rate was 2 per second. By varying the current, the coils produced fields consisting of sham (no current) and peak magnetic fields of 0.03 mT, 0.3 mT, and 3 mT, corresponding to peak induced electric fields of 1, 10, and 100 µV/cm, respectively, at the tissue target. Walking function was assessed over 43 days using video recording and measurement of the 1–5 toe‐spread, using an imaging program. Comparing injured to uninjured hind limbs, mean responses were evaluated using a linear mixed statistical model. There was no difference found in recovery of the toe‐spread function between any EMF treatments compared to sham. Bioelectromagnetics 28:256–263, 2007. © 2007 Wiley‐Liss, Inc.
Qualified Estimation of Two Measures of Diversity Within Populations
Authors: Gillet Elizabeth M.
Published: February 2007

Estimation of diversity within populations is a major concern in population genetics. An approach in the framework of hypothesis testing is developed, in which all hypothetical population frequencies that are not rejected on the basis of the sample frequencies define a confidence region. The test criterion requires that the sample be drawn according to a method of investigation that is qualified a priori, meaning that the probability of obtaining a sample with discrepancy not less than a given critical discrepancy from the true population frequencies not be greater than a given level of significance. Since a descriptor, such as diversity, is always a characteristic of the base population, confidence limits for the descriptor should be derived as the range of the descriptor throughout the confidence region or, by the duality between the non‐rejected hypotheses and the confidence region of a sample, as the range of the descriptor for all non‐rejected base populations. A table of minimal sample sizes for qualification is given. Geometric representations of the limits of confidence regions in 𝒮3 and 𝒮4 are shown for the absolute distance measure d0 of the discrepancy between frequency distributions. This method is applied to two measures of diversity commonly used in population genetics. Bounds on their derived confidence intervals are inferred. The computer program DIVSTAT used for calculations is introduced. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Analysis of Longitudinal Count Data with Serial Correlation
Authors: Xu Stanley , Jones Richard H. , Grunwald Gary K.
Published: February 2007

We propose a state space model for analyzing equally or unequally spaced longitudinal count data with serial correlation. With a log link function, the mean of the Poisson response variable is a nonlinear function of the fixed and random effects. The random effects are assumed to be generated from a Gaussian first order autoregression (AR(1)). In this case, the mean of the observations has a log normal distribution. We use a combination of linear and nonlinear methods to take advantage of the Gaussian process embedded in a nonlinear function. The state space model uses a modified Kalman filter recursion to estimate the mean and variance of the AR(1) random error given the previous observations. The marginal likelihood is approximated by numerically integrating out the AR(1) random error. Simulation studies with different sets of parameters show that the state space model performs well. The model is applied to Epileptic Seizure data and Primary Care Visits Data. Missing and unequally spaced observations are handled naturally with this model. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A time‐resolved immunofluorometric assay for porcine C‐reactive protein quantification in whole blood
Authors: Martinez‐Subiela S. , Eckersall P. D. , Campbell F. M. , Parra M. D. , Fuentes P. , Ceron J. J.
Published: February 2007

A time‐resolved immunofluorometric assay (TR–IFMA) for C‐reactive protein (CRP) determination in whole blood of pigs was developed and validated. CRP was isolated from porcine acute‐phase serum by affinity chromatography on agarose, coupled with phosphorylethanolamine and polyclonal antibodies to porcine CRP were purified from antiserum raised in sheep immunized with porcine CRP. Intra‐ and inter‐assay coefficients of variation (CVs) were in the range 3.13–7.19% and 7.06–15.66%, respectively, showing good precision. The assay measured the CRP values in a proportional and linear manner (r= 0.99); additionally, CRP concentrations measured in whole blood by the present TR–IFMA and in serum by an established immunoturbidimetric assay were highly correlated (R2= 0.97). The limit of detection of the method was 0.0028 mg/L. Significantly lower CRP concentrations were observed after 7 days of sample storage at 4°C. The injection of turpentine oil caused a significant increase in CRP concentrations and significantly higher CRP concentrations were observed in pigs with pathological processes compared to healthy animals. Copyright © 2007 John Wiley & Sons, Ltd.
Optimizing the tuning parameters of least squares support vector machines regression for NIR spectra
Authors: Coen T. , Saeys W. , Ramon H. , De Baerdemaeker J.
Published: February 2007

Partial least squares (PLS) is one of the most used tools in chemometrics. Other data analysis techniques such as artificial neural networks and least squares support vector machines (LS‐SVMs) have however made their entry in the field of chemometrics. These techniques can also model nonlinear relations, but the presence of tuning parameters is a serious drawback. These parameters balance the risk of overfitting with the possibility to model the underlying nonlinear relation. In this work a methodology is proposed to initialize and optimize those tuning parameters for LS‐SVMs with radial basis function (RBF)‐kernel based on a statistical interpretation. In this way, these methods become much more appealing for new users. The presented methods are applied on manure spectra. Although this dataset is only slightly nonlinear, good results were obtained. Copyright © 2007 John Wiley & Sons, Ltd.
Cover Picture: Tuning the Polarization Along Linear Polyaromatic Strands for Rationally Inducing Mesomorphism in Lanthanide Nitrate Complexes (Chem. Eur. J. 6/2007)
Authors: Terazzi Emmanuel , Guénée Laure , Morgantini Pierre‐Yves , Bernardinelli Gérald , Donnio Bertrand , Guillon Daniel , Piguet Claude
Published: February 2007

The bottom‐up design of luminescent lanthanide‐containing thermotropic liquid crystals is depicted on the cover. In their Full Paper on page 1674 ff., C. Piguet, P.‐Y. Morgantini et al. describe how the specific orientation of the carboxylic spacers in the molecular building blocks induces significant changes in the aromatic polarizations as measured by the electrostatic potential calculated on the Connolly surface. Only a sufficient set of polarization alternances produces enough intermolecular enthalpic cohesion compatible with the formation of liquid‐crystalline phases.
Sb2Hg3GaBr4: A New Supramolecular Framework Structure with [Sb2Hg4/2].+‐.0 Building Blocks Isosteric to Distibane.
Authors: Schlirf J. , Deiseroth H. J.
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Chemical Vapor Transport and Crystal Structure of Rare‐Earth Antimonates(V) — LnSbO4.
Authors: Gerlach Sylvia , Cardoso‐Gil Raul , Milke Edgar , Schmidt Marcus
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
The Use of Vinyl Sulfonium Salts in the Stereocontrolled Asymmetric Synthesis of Epoxide‐ and Aziridine‐Fused Heterocycles: Application to the Synthesis of (‐)‐Balanol.
Authors: Unthank Matthew G. , Hussain Nigel , Aggarwal Varinder K.
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.