What is marine biology?: Defining a science in the United States in the mid 20th century

Marine biology and biological oceanography are two disciplinary subfields that have long struggled with their definitions. Should marine biology simply be considered a part of biology that takes place in the marine environment or is it a distinct entity, with conceptual problems and methodological approaches all its own? Similarly, biological oceanography could be seen as a necessary adjunct to physical and chemical oceanography or it could be defined more as an extension of biology into the marine realm. In the United States, these issues were directly addressed from the mid 1950s through the mid 1960s in a series of events that shed light on how marine biologists came to a working definition of their field that provided a broad methodological tent for practitioners and, at the same time, allied the field to oceanography during a period in which exploration of uncharted areas drew considerable funding from the post-WWII federal agencies charged with keeping American science at the forefront.     

An outpost of progress: Development in the northern Kasai region of Zaïre in the early 20th century

Ritual is the main topic of ‘Culture, Thought and Social Action’. Tambiah, in some of the most important essays of this collection, denies any efficiency to the dualistic approaches which contrast thought and action, word and deed, facts and representation. Marc Augé agrees with such a conception but wonders whether the definition of the sense as cultural and total which Tambiah tries to develop is congruent with the necessity of comparison he claims for in the same time.     

Evolutionary embryology resurrected in Japan with a new molecular basis—Nori Satoh and the history of ascidian studies born in Kyoto in the 20th century

This paper was written in honor of Dr. Noriyuki Satoh who was awarded A.O. Kowalewsky medal, an international prize of the St. Petersburg Society of Naturalists. We congratulate and thank this eminent zoologist for his outstanding scientific achievements, for his life’s work in the discipline founded by A.O. Kowalewsky. Published in Russian in Ontogenez, 2006, Vol. 37, No. 6, pp. 474–477. The text was submitted by the authors in English.     

Making a Mechanical Organism Being the fourth in a series of essays on the materials of nature

Most multicellular organisms can be categorised by two words： hierarchy and composite. The underlying fractal geometry of nature - at least in terms of provision of infrastructure - provides much of the hierarchy, although many materials for which infrastructure is not an integral factor are also strongly hierarchical. Plants can therefore be modelled using recursive computer programs which add structures as the size increases. However, problems with mechanical stability also increase as the structure grows, so the plant changes from deriving stiffness from intevaal pressure to cross-linking the cell wall components permanently. However, this compromises the ability of the plant to grow and repair itself.     

Characterization of a polymorphism in the 3′ part of the chicken vitellogenin gene

Summary An allele giving rise to a polymorphism within the 3 part of the chicken vitellogenin gene was cloned, sequenced, and compared to the previously cloned allele. The polymorphism is formed by a perfect copy of 343 bp from intron 32 in tandem array with a perfect copy of 244 bp from intron 33; this 587-bp element is inserted in a head-to-tail arrangement in intron 33. We propose a mechanism in which an unequal crossing-over resulted in a vitellogenin gene with two exons 33, one of which was subsequently deleted. Thus, intron 33 was enlarged by the tandem repeats without affecting the protein-encoding sequence of the gene. At the boundaries of the repeated elements, two short direct repeats are found that resemble the recombination signals of immunoglobulin genes. They may have had a key role in the formation of the new allele.     

Progress of a half century in the study of the Luria-Delbrück distribution

The Luria-Delbrück mutation model has been mathematically formulated in a number of ways. This review article examines four most important formulations, focusing on important practical issues closely linked with the distribution of the number of mutants. These issues include the probability generating functions, moments (cumulants), computational methods and asymptotics. This review emphasizes basic principles which not only help to unify existing results but also allow for a few useful extensions. In addition, the review offers a historical perspective and some new explanations of divergent moments.     

Influence of the radial profile of the electric potential on the confinement of a high-β two-component plasma in a gas-dynamic trap

One of the most important problems to be studied in the gas-dynamic trap (GDT) facility is the investigation of MHD stability and cross-field transport in a plasma with a relatively high value of β = πp/B ². Recent experiments demonstrated that the radial electric field produced in the plasma by using radial limiters and coaxial end plasma collectors improves plasma stability in axisymmetric magnetic mirror systems without applying special MHD stabilizers. The experimental data presented in this work show that stable plasma confinement can be achieved by producing a radial potential drop across a narrow region near the plasma boundary. Creating radial electric fields of strength 15–40 V/cm causes a shear plasma flow, thereby substantially increasing the plasma confinement time. When all the radial electrodes were grounded, the confinement was unstable and the plasma confinement time was much shorter than the characteristic time of plasma outflow through the magnetic mirrors. Measurements of cross-field plasma fluxes with the use of a specially designed combined probe show that, in confinement modes with differential plasma rotation, transverse particle losses are negligibly small as compared to longitudinal ones and thus can be ignored. It is also shown that, when the GDT plasma is in electric contact with the radial limiters and end collectors, the growth rate of interchange instability decreases considerably; such a contact, however, does not ensure complete MHD stability when the electrodes are at the same potential.     

Progress in deciphering the information content of the ‘glycome’ – a crescendo in the closing years of the millennium

The closing years of the second millennium have been uplifting for carbohydrate biology. Optimism that oligosaccharide sequences are bearers of crucial biological information has been borne out by the constellation of efforts of carbohydrate chemists, biochemists, immunochemists, and cell- and molecular biologists. The direct involvement of specific oligosaccharide sequences in protein targeting and folding, and in mechanisms of infection, inflammation and immunity is now unquestioned. With the emergence of families of proteins with carbohydrate-binding activities, assignments of information content for defined oligosaccharide sequences will become more common, but the pinpointing and elucidation of the bioactive domains on oligosaccharides will continue to pose challenges even to the most experienced carbohydrate biologists. The neoglycolipid technology incorporates some of the key requirements for this challenge: namely the resolution of complex glycan mixtures, and ligand binding coupled with sequence determination by mass spectrometry.     

Tree rings as a surrogate for economic stress – an example from the Puna of Jujuy,Argentina in the 19th century

This paper illustrates the use of tree-ring indices as an indicator of economic stress. In the 19th century the rural economy in the Puna of Jujuy, Northwestern Argentina was based on livestock (llamas and sheep), and was heavily dependant on the availability of pasture and water in this arid landscape. In the absence of traditional indicators of socioeconomic stress, we used tree-ring indices from moisture sensitive trees (Juglans australis Griseb. and Polylepis tarapacana Phil.) as a proxy for droughts and their related economic stresses. Examining the relationship between population mortality and ring-width indices allows inferences to be drawn about the relative importance of environmental and sociopolitical factors in determining mortality patterns that contributed to the depopulation of this area in the late 19th century.     

Wood use in a medieval village: the contribution of wood charcoal analysis to the history of land use during the 13th and 14th centuries a.d. at Pobla d’Ifach, Calp, Alicante, Spain

Excavations on the Rock of Ifach, Alicante, Spain have revealed the remains of a medieval settlement that flourished between a.d. 1297 and 1359. Wood charcoal analysis combined with archaeological evidence and historical records allow an assessment of the local vegetation of the area during the medieval period, the obtaining and use of firewood and the commercial routes for supplying timber. Pinus halepensis and to a lesser degree various matorral taxa were used for fuel during the main occupation phases at the settlement. The resource exploitation network of the settlement expanded over the adjacent coastal area, with firewood obtained from pine woodlands there. The timbers used in the construction of the settlement were mainly from pines that originated nearby (P. halepensis) or which were transported by river from woodland areas to the north which were controlled by the Crown of Aragon (P. nigra/sylvestris, P. pinaster). The partial destruction of the village in a.d. 1359 and its gradual abandonment are reflected in changes observed in fuel supplying practices that then concentrated on the local matorral vegetation of the rock itself.     

Transglycosylation of a β-galactosyl radical, in the course of enzymic hydrolysis of lactose, in the presence of selected polyhydroxyalcohols

Sorbitol, xylitol, erythritol and lactitol were used as the acceptors of galactosyl radicals, in the process of transgalactosylation accompanying the hydrolysis of lactose, conducted with -galactosidase (4.0 ml Lactozym 3000 was added to 430 ml 1.45 M lactose with 0.95 M polyhydroxyalcohols). The following concentrations of galactosyl derivatives of polyols were obtained after hydrolysis for 4 h at 40°C: 0.31 M Gal-erythritol, 0.22 M Gal-xylitol, 0.18 M Gal-sorbitol and 0.14 M Gal-lactitol. A quadruple increase of xylitol content in dry matter of a solution (from 11.5% (w/w) to 44.5% (w/w) brought about a 2.3-fold increase of the product content in the solution (15.2% (w/w) of dry matter).     

Festschrift in the Honor of Stephen H. White��s 70th Birthday

The Symposium 'Frontiers in membrane and membrane protein biophysics: experiments and theory', held this year at the University of California, Irvine (August 19-20), celebrated the 70th Birthday of Stephen H. White by bringing together distinguished experimentalists and theoreticians to discuss the state of the art and future challenges in the field of membrane and membrane protein biophysics. The meeting and this special issue highlight the highly interdisciplinary nature of membrane and membrane protein biophysics, and the tremendous contributions that S. H. White and his lab have brought to the field.     

Farming in a rural settlement in central Italy: cultural and environmental implications of crop production through the transition from Lombard to Frankish influence (8th–11th centuries a.d.)

Plant macrofossil (carpological) and morphometric analyses were carried out on plant remains from the medieval castle of Miranduolo, Siena, a rural settlement in central Italy with a long sequence of occupation between the 8th and the 11th centuries a.d. The presence of Triticum aestivum/durum and Vicia faba var. minor from the first phase of the Lombard farming village suggests continuity with the agricultural tradition of the preceding Roman world, and the use of good cultivation techniques that allowed quality yields to be obtained from rather poor soils. At the same time, the significant presence of the primitive cereal T. monococcum, compared with the archaeobotanical literature of north-central Italy, allows to us consider it as a “cultural” element of Lombard farming. In the next cultural phases, with the Carolingian manor and then with the feudal castle, the stable presence of T. aestivum/durum and the reduction of T. monococcum in favour of more productive cereals such as Secale cereale and Hordeum vulgare indicate a further improvement in productivity. This is also confirmed by the appearance of fruits and nuts such as Castanea sativa, Vitis vinifera and Prunus persica. The increase in caryopsis sizes of T. monococcum and T. aestivum/durum in the transition from the village to the manorial phase is a consequence of the improvements in farming. The decrease in caryopsis size of T. monococcum from the manor phase to that of the castle testifies the decreasing importance of this cereal. The good date resolution of this research allows us to detect the crops, the storage and the processing practices, as well as the changing role of crop plants in the rural economy. This highlights the geographical, historical-cultural and political factors of the medieval transition from the Lombard to the Carolingian and then to the feudal period in central Italy.     

Fragmentation of the Québec population genetic pool (Canada): evidence from the genetic contribution of founders per region in the 17th and 18th centuries

The 6 million French-Canadians of Québec derive from a relatively small number of founders. Consequently, some hereditary diseases, which may or may not present a worldwide distribution, have been detected in high frequency in this population. Several studies, however, indicate a nonuniform distribution of these diseases through the population, suggesting that the French-Canadian founder effect has been geographically stratified. Here we explore this stratification by using a demographic database, the Population Register of Early Québec, that contains almost all birth, marriage, and death certificates (>712,000) recorded in parish registers between 1608-1800. In this database, every genealogical link has been traced back to the founders of the population, so that we can compute the genetic contribution of founder per region, and then account for the early events that have shaped the distribution of diseases. Ten regions, comprising varying numbers of parishes, have been selected. We first describe each region in terms of homogeneity and concentration of its gene pool. For this purpose, a new concept is introduced, the founders' uniform contribution number (FUN), i.e., the number of founders a population would have if all its founders had an equal contribution. Second, we estimate genetic similarity between regions on the basis of differential genetic contribution. To classify the regions, we use principal component and cluster analysis. Our results show a tripartite clustering of the population, and invite us to reconsider the results obtained from biomolecular and clinical studies, which show a bipartite clustering.     

What's in the genome of a filamentous fungus? Analysis of the Neurospora genome sequence

The German Neurospora Genome Project has assembled sequences from ordered cosmid and BAC clones of linkage groups II and V of the genome of Neurospora crassa in 13 and 12 contigs, respectively. Including additional sequences located on other linkage groups a total of 12 Mb were subjected to a manual gene extraction and annotation process. The genome comprises a small number of repetitive elements, a low degree of segmental duplications and very few paralogous genes. The analysis of the 3218 identified open reading frames provides a first overview of the protein equipment of a filamentous fungus. Significantly, N.crassa possesses a large variety of metabolic enzymes including a substantial number of enzymes involved in the degradation of complex substrates as well as secondary metabolism. While several of these enzymes are specific for filamentous fungi many are shared exclusively with prokaryotes.     

A comparison of ten digestive enzymes reveals a lack of chitinase in a phasmid and the loss of two β-glucanases in a mantid

In all developmental stages, the phasmid Peruphasma schultei (Conle & Hennemann, 2005) is an obligate herbivore, whereas the mantid Hierodula membranacea (Burmeister, 1838) is an obligatory carnivore. In P. schultei, the luminal activity of all enzymes is approxximately 50% in the crop and 50% in the midgut, which corresponds to the approximate 50 : 50 ratio of volumes of these two regions. These ratios would be expected in insects with a constant feeding rate on an unvaried diet. The enzyme activity and volume ratios in Hierodula membranacea vary considerably because of the irregular feeding habits. These differences in activity ratios between phasmids and mantids are not associated with the obligate phytophagous or carnivorous diet. The ratio of membrane bound to luminal aminopeptidases and disaccharidases in the midgut of both species are not significantly different and are within the normal range of other paurometabolous insects. Cellobiase and other plant cell wall digesting enzymes, laminarinase and cellobiase, are present in the phasmid but totally lacking in the mantid. The obligate carnivorous feeding habits of mantids could represent a selective factor leading to the loss of the ability to produce β-glucanases. Chitinase is a moulting enzyme in all insects, whereas, in H. membranacea, chitinase also occurs as a luminal digestive enzyme. This modified enzyme function requires production and secretion in another tissue, namely the midgut.