bluuebunny/crossref_metadata_2025_split huggingface dataset:
ADAPTATIONS OF TERRESTRIAL ARTHROPODS TO THE ALPINE ENVIRONMENT
Authors: SØMME LAURITZ 
Published: January 2008

Summary1. The climate changes drastically above the timberline. Diverse adaptations have been evolved by insects and other terrestrial arthropods to survive the alpine environment. The fitness of each species depends on a combination of different factors in accordance with their special habitats.2. Morphological adaptations such as reduced body‐size, are known from a number of alpine insects, increasing their possibility to find sheltered microhabitats. Selection for reduced body size in Andean Phulia spp. butterflies is probably a result of their rigorous environment. Wing atrophy, which is also known in insects from other extreme environments, is widespread in alpine species. In several terrestrial arthropods the absorption of solar radiation is increased by melanism. Increased pubescence, protecting against the loss of heat, is known in alpine butterflies and bumblebees.3. Several behavioural adaptations are described. Thermoregulatory behaviour is important in many species to raise their body temperatures. Alpine butterflies orient the dark basis of their wings perpendicular to the rays of the sun. Body temperatures of 30 °C may be required for flight. To increase their activities many alpine terrestrial arthropods seek warmer microhabitats in the vegetation and under rocks. The adaptive advantage of nocturnal activity as observed in several species, may be to maintain the water balance or to avoid predation.4. Tropical alpine terrestrial arthropods are faced with special problems. The large diel temperature fluctuations require cold‐hardiness during the night and tolerance to heat during the day. Many species seek sheltered microhabitats under rocks and in vegetation.5. Due to low precipitation and high evaporation rates many mountain areas are extremely dry. High resistance to desiccation may be very important to alpine species, and in particular to tropical species. Rates of water loss at low relative humidities are comparable to those of desert arthropods.6. As an adaptation to the cold alpine summers several species of terrestrial arthropods require more than one year to complete their life‐cycles. Special to these species is their adaptation to low temperatures in two or more overwintering stages. In spite of their cold surroundings several species have univoltine life cycles, frequently combined with highly specialized adaptations. Increased metabolic rates as a compensation to low temperatures may be widespread in alpine species, but few data are available.7. Cold tolerance is of particular importance in temperature alpine species. Winter survival in Collembola and Acari depends on supercooling. Great seasonal variations have been observed in a number of species. Freezing tolerance is also known from alpine insects, e.g. in some species of beetles. At high latitudes alpine species must endure periods of up to eight or nine month at low temperatures during hibernation. Anaerobiosis is known from species that are enclosed in ice, with lactate as the main end product of metabolism.
EXPERIMENTS ON THE LIMITATION OF BIRD NUMBERS BY TERRITORIAL BEHAVIOUR
Authors: NEWTON I. 
Published: January 2008

Summary(1) This paper examines removal and other experimental studies on the role of territorial behaviour in the limitation of bird densities. Experimental design is discussed, as are the types of conclusions that can be drawn.(2) Experiments have been conducted on more than 40 species from a wide range of taxonomic groups. Most provided evidence for density limitation, probably mediated by territorial behaviour, and for the existence of a non‐territorial sector able to take territories when territory owners were removed or when additional habitat was made available. Experiments in the breeding season indicated that some surplus birds, although younger on average then territorial birds, were sexually mature and able to breed when given the chance. In some species, replacement birds bred less well than other territorial birds, but in other species no difference was apparent between the two groups.(3) Other experiments indicated that, while density was limited by territorial behaviour in good habitats, this was not the case in poor habitats, and that some individuals would move from poor to good habitat when territory owners were removed from good habitat.(4) In some species, non‐territorial birds of breeding age were present in the population despite the existence of vacant territorial sites, while in others replacements were observed on good territories but not on poor ones. The implications were that site quality influenced whether settlement, defence and breeding occurred, and that some individuals had more stringent site requirements than others. In some seabirds' sites in the centre of a colony were more attractive than sites on the edges.(5) Many land‐bird species that have been studied show two peaks of territorial activity each year, in autumn and in spring, and a limitation on breeding density can occur at either or both seasons, depending on conditions.(6) The fact that densities of many bird species fluctuate greatly from year to year is not inconsistent with the limitation of density by territorial behaviour. Several mechanisms are apparent through which density might be limited by territorialism at different levels in different years, so that surplus non‐territorial birds are present in years of low territorial density, as well as in years of high territorial density.(7) Experiments have shown that density is limited by the presence of territorial birds, in some species at different levels in different areas or years. The next step is to find whether density is regulated by the presence of territorial birds over a period of years in a density‐dependent manner. For this, observational data are required to find whether the proportion of birds that is excluded by territorial behaviour each year varies with the total number available for settlement. Such studies can be made only on species in which non‐territorial birds can be counted accurately, as well as territorial ones.
ON THE GENERATION OF FORM BY THE CONTINUOUS INTERACTIONS BETWEEN CELLS AND THEIR EXTRACELLULAR MATRIX
Authors: ETTINGER LIA , DOLJANSKI FANNY 
Published: January 2008

SummaryThe central issue of this essay is the problem of how multicellular organisms develop and maintain the complex architecture and intricate shape of tissues and organs. The concepts pattern formation, morphogenesis and differentiation are defined and discussed suggesting a distinction between processes that underlie uniformity (e.g. basic body plans) and those underlying inter‐ and intra‐species variation. The initial stage of limb bone development ‐ the formation of the mesenchymal condensation — is described in detail. On the basis of these data and many additional examples from other developmental systems, the central role of continuous cell‐ECM interactions in the generation of form is deduced. Evidence is provided as to the leading role of the mesenchymal‐fibroblast‐like cells in sculpturing tissue and organ architecture. It is proposed that a group of cells within their ECM, rather than the single cell, is the functional unit relevant to the generation of form.The continuous cell‐ECM interactions lead to the generation of form not by a detailed obligate pathway, but rather by a process of ‘selective stabilization’ (Kirschner & Mitchison, 1986), i.e. a gradual organization into more stable structures, where existing structural configurations serve to increase the likelihood of certain configurations and reduce that of others. Data are quoted to support the notion that even cell division does not erase all the structural information imprinted in the cell. The role of the metazoan genome in morphogenesis is discussed in the light of the process of selective stabilization.
THE RELATIVE IMPORTANCE OF SHORT‐ AND LONG‐RANGE MOVEMENT OF FLYING APHIDS
Authors: LOXDALE HUGH D. , HARDIE JIM , HALBERT SUSAN , FOOTTIT ROBERT , KIDD NEIL A. C. , CARTER CLIVE I. 
Published: January 2008

Summary1. Aphids are notorious pests of world agriculture. Even so, uncertainty persists as to their capacity for successful aerial dispersal. Evidence exists that, under some conditions, aphids can be wind‐borne over long distances, i.e. hundreds of kilometers over desert or sea. It has been argued, in the recent past, that this phenomenon may be part of a strategy to locate fresh host plants in new distant areas. However, the proportion of these insects successfully colonizing new hosts is unknown.2. Other work using meteorological backtracking has also indicated long‐distance movement, but the accuracy of such predictions is dubious unless the altitude of transport is known. Mark‐releaseecapture experiments with such small insects have limited potential due to large dilution effects. Static ‘snap‐shots’ of demographic population densities, using suction traps, cannot accurately distinguish local aerial density fluxes and population movements from a distance. However, genetic and physiological markers may provide more direct information on population mixing; for example, some allozyme studies have shown a limited level of inter‐population gene flow.3. Under suitable conditions, aphids take off, maintain flight and alight in response to the appropriate visual and olfactory cues. Undoubtedly successful long‐distance movement occurs from time to time, but its ecological relevance may have been overstated in the past. It may be selectively disadvantageous for aphids to move from areas containing their host plants. In contrast, it is advantageous for aphids to maximise their chances of survival and reproductive success by landing on suitable plant hosts at the earliest opportunity.4. The clonal nature of aphids (a single genotype may comprise vast numbers of individuals) means that there may be advantages to phenotypic variation between individuals in the readiness to move. Recent evidence indicates that such a variation exists in the duration of the behavioural migratory phase, the initial period of maiden flight when host‐plant cues are ignored and when landing is inhibited.5. The relative biological importance of short‐ us. long‐distance movements is reassessed with reference to plant virus epidemiology and the spread of new genotypes, e.g. insecticide resistance. It is concluded that the biological relevance of short‐distance movements have a much greater impact on population and genotype distribution than long‐distance movements, which may be comparatively infrequent.
THE STRIPED COLOUR PATTERN AND STRIPED/NON‐STRIPED POLYMORPHISM IN SNAKES (REPTILIA: OPHIDIA)*
Authors: WOLF MOSHE , WERNER YEHUDAH L. 
Published: January 2008

SummaryThe occurrence of striped colour patterns and of striped/non‐striped polymorphism systems among snakes is reviewed from literature data augmented by some personal observations. Among 1367 species, 190 were striped or had striped morphs. Of 11 families, the striped pattern was common mainly among Colubridae, presumably in relation to the active escape behaviour strategy, prevalent in this family. The striped species tended to cluster in a small number of genera.The 40 striped/non‐striped polymorphism systems found, fall into five categories, according to the coloration patterns of the alternative morphs: (I) blotched (cryptic); (2) barred (or ringed); (3) plain; (4) melanistic; (5) albinistic. Most polymorphisms are presumably maintained by eco‐behavioural trade‐offs, depending on the category and on the habitat: The striped morph is presumed more effective in active escape and sometimes also in camouflage; the alternative morph may be more effective in camouflage, in active escape or in thermoregulation. Hence morph frequency depends on the habitat. Striped‐albinistic polymorphism in Elaphe climacophora presumably depends on human protection of the albino morph.
THE REGULATION OF ALTERNATION OF GENERATION IN FLOWERING PLANTS
Authors: Dickinson By H. G. 
Published: January 2008

SummaryThe developmental changes involved in the alternation of generation represent the major gene‐switching events in the life history of plants. While a large number of genes are common to both sporophyte and gametophyte, many thousand sequences are specifically expressed in each generation; indeed, certain key constituents (e.g. tubulin) are encoded by different genes in each generation, indicating that sporophyte and gametophyte are responding to different evolutionary pressures. Evidence is accumulating that major gene‐switching events in plants, such as flowering, are regulated by complex control systems which ensures that development occurs only in the correct groups of cells at the appropriate time. A similar, or more sophisticated system might thus be expected to regulate alternation of generation. It is not possible to manipulate alternation of generation in a similar fashion to flowering, but study of apparent aberrations of development occurring in nature and in vitro suggests that alternation only occurs in cells which have become competent to receive particular developmental stimuli. Further, in certain cases, competent cells may be switched either into sporophytic or gametophytic developmental pathways depending upon the nature of the stimulus. Acquisition of competence seems to involve isolation of cells from the symplast, some cytoplasmic dedifferentiation, and perhaps cell cycle arrest or transition. The stimuli in vivo appear metabolic in nature, although embryogenesis may be activated by specific classes of glycoproteins. Interestingly, examination of agamospermic systems suggests that fertilization of the egg per se is not the signal which activates sporophytic development. Once competent cells have received the stimulus they start to develop, with no delay in a ‘determined’ state. Sporophytic and gametophytic development in vivo and in vitro both start with an asymmetric division, except for the female gametophyte which may arise via a range of developmental pathways, depending on the species.
Clinical and experimental Studies in Amyloidosis.1,2,3
Authors: GRAYZEL H. G. , JACOBI M. , WARSHALL H. B. , BOGIN M. , KRAMER B. 
Published: January 2008

Summary1. The method of production of amyloid is described briefly.2. Powdered whole liver added to the diet markedly retards the formation of amyloid.3. A similar effect is produced by the addition of vitamins A and B in combination to the diet.4. Cholesterol, two liver extracts, and ground beef exert no such effects.5. Powdered whole liver added to the diet brings about the resorption of previously formed amyloid already deposited in the organs in moderate amounts.6. The rôle of the reticulo‐endothelial system in the production of amyloidosis is briefly discussed.7. The inter‐relation of the powdered whole liver and the reticulo‐endothelial system in the resorption of amyloid is suggested and discussed briefly.
Erworbene Lähmungen bei jungen Säuglingen.
Authors: LANGE. Prof. Dr. CORNELIA DE 
Published: January 2008

Zusammenfassung.Mitgeteilt werden zwei Fälle von Lähmungen bei jungen Säuglingen. Im ersten Fall handelte es sick um ein Kind von 5 Wochen, wo die Arme ganz sehlaff waren, die Beine etwas weniger. Es gelang nicht, die Ätiologie festzustellen, wenn auch anfänglich Diphtherie einigermassen wahrscheinlich schien. Die pathologisch‐anatomische TJntersuchung war ganz negativ.Im zweiten Fall wurde das Kind am 15. Lebenstag krank mit leichten Zuckungen, darauf folgte eine vollständige Lähmung von Armen, Beinen, Atmungsmuskeln, Halsmuskeln. Tod am 20. Lebenstag durch Atmungsinsuffizienz infolge Entzündung des Cervikal‐ und Thorakalmarks. Die Ganglienzellen im Vagusgebiet waren ziemlich intakt, wenn es auch stellenweise etwas Infiltrat in den Kernen gab.Gemäss dem, was die schwedischen Untersucher bereits vor Jahren gesagt haben, nämlich dass in jedem ernsten Fall von Poliomyelitis eine diffuse Ausbreitung des Prozesses über den Gehirnstamm die gewöhnliche Ausbreitung sei, wurde eine Myelo‐Encephalitis disseminata gefunden, die besonders stark war im Lumbal‐ und im Cervikalmark, in der Substantia reticularis und in der Substantia nigra. Anlässlich letzterer Tatsache wird hingewiesen auf das (mit einer einzigen Ausnahme) Fehlen von Parkinsonismus in der mitgeteilten Symptomatologie der Heine‐Medinschen Krankheit und wird die Vermutung ausgesprochen, das bisweilen mit Unrecht die Diagnose Encephalitis epidemica gestellt sein möge in Fällen, die zur Heine‐Medinschen Krankheit gerechnet werden sollten. Es wird als nicht richtig erachtet, dass die rumänischen Untersucher anlässlich eines Falles von vorübergehendem Parkinsonismus bei einem Mädchen mit der Heine‐Medin‐schen Krankheit einen neuen, mesocephalen Typus aufstellen wollen.Man muss Pette, Demme und Kornyey (l. c.) durchaus beistimmen, dass es nötig ist, um, wie Überall, auch in der Substantia nigra, zu unterscheiden zwischen mesodermalgliogener Reaktion und dem Ergriffenwerden der Ganglienzellen selbst. In ersterem Fall ist kein Parkinsonismus zu erwarten.Es gelang nicht, in den Ganglienzellen der am stärksten angegriffenen Teile des Rückenmarks Kerneinschlüsse zu fin‐den. Die Aufmerksamkeit wird gelenkt auf die Entartung der intra‐ und extramedullären Wurzelfasern, welche innerhalb weniger Tage auftrat.Eine Hyperplasie des lymphoiden Gewebes wurde nicht angetroffen. Veränderungen in Muskeln und peripherischen Nerven konnten nicht festgestellt werden.Es wird künftighin von Bedeutung sein, bei Obduktionen auch zu achten auf die von Marinesco, Mouriquand, Dechaume und Sédallian gefundenen Prozesse im Darmplexus und in den Ganglia semilunaria, also im neuro‐vegetativen System.Die Ansicht Spielmeyers, dass der vasale und der Systemfaktor bei der Entstehung der Poliomyelitis keine Rolle spielen, sondern dass das Wesentliche sei die primäre Ent‐zündung der grauen Substanz mit der starken Reaktion des Gefässbindegewebssystem im Sinn einer resorptiven Entzün‐dung, vermag die histologischen Bilder des vorliegenden Falles am besten zu erklären.
Maladie kystique du poumon et sclérose tubéreuse du cerveau
Authors: BERG GUNNAR , VEJLENS GERT 
Published: January 2008

Résumé.Les auteurs décrivent un singulier cas pathologique d'espèce rare, mais offrant certainement un intérêt médical général. Une femme de 32 ans décède d'une maladie pulmonaire chronique, sans présenter de signes de maladie cérébrale. L'examen roentgen et l'autopsie démontrent une altération totale des deux poumons, transformés en kystes, de type inconnu jusqu'ici. A l'autopsie, on constata en outre une sclérose tubéreuse du cerveau avec ses manifestations secondaires habituelles, c. à. d. des tumeurs dans la peau du visage et dans les reins ainsi qu'un splénome dans la rate, altérations qui toutes peuvent être considérées comme intermédiaires entre tumeurs et malformations.Les auteurs soutiennent l'opinion que toutes ces altérations constituent des phénomènes partiaux d'une maladie générale de malformation, et qu'elles pourraient opportunément être rangées sons la dénomination commune de sclérose tubéreuse (cf. Josephy).En raison de la présence d'altérations pathologiques concomitantes dans les ovaires, dans l'hypophyse et dans les glandes surrénales, les auteurs expriment la supposition qu'il existe un rapport entre l'apparition de cette maladie tumorigène de malformation et une rupture d'équilibre des fonctions des organes endocriniens. Addenda. Une soeur de la défunte, de deux ans plus jeune qu'elle, vient d'être examinée postérieurement à l'envoi du manuscrit à l'impression. On constata des naevi de type Pringle au visage, et l'examen roentgenologique montra des altérations pulmonaires cystiques bilatérales étendues.
Allergy and immunity (iathergy) in experimental tuberculosis
Authors: BIRKHAUG KONRAD 
Published: January 2008

Summary.Carefully controlled studies were made of the leukocytic reactions in BCG‐immunized guinea pigs infected with virulent bovine tubercle bacilli and subsequently allowed to remain in the allergic or the completely desensitized iathergic state. The following significant changes were noted:1. No clear‐cut deviations in the total leukocyte counts were observed to justify the claim that the variations in leukocytosis alone is a reliable indicator of the degree of tuberculous activity.2. The monocyte‐lymphocyte ratio is a more sensitive and reliable indicator of tuberculous activity than the neutrophile‐lymphocyte ratio and the neutrophile »shift to the left».3. The leukocytic index is a valuable aid to accurate interpretation of the leukocytic reactions in terms of favourable or unfavourable pathological activity.4. The monocyte‐lymphocyte ratio and the leukocytic index furnish reliable evidence that the abolition of allergic hypersensitiveness by careful tuberculin desensitization leaves the mechanism of acquired tuberculo‐resistance intact and significantly retards the pathological activity of virulent tubercle bacilli.
Ernährungszustand und Zahncaries
Authors: JUNDELL I. , BERLIN V. 
Published: January 2008

Zusammenfassung.An einem Material von Volksschulkindern, die in der Schule in der möglichst besten Weise zahnärztlich beobachtet und besorgt wurden und an denen die allgemeine Körperentwicklung während der Schuljahre genau registriert word en war, konnte eine regel‐mässige Beziehung zwischen Über‐ bezw. Unterernährung und Zahncaries nicht nachgewiesen werden.
The Treatment of Morbus Haemolyticus Neonatorum (Familial Erythroblastosis Foetalis). Guiding Lines for Experiments towards an Improvement
Authors: BROMAN BIRGER 
Published: January 2008

Summary.The conception that Rh incompatibility between mother and foetus is the cause of familial erythroblastosis foetalis (morbus haemolyticus neonatorum) to far more than 90% has considerably helped on the diagnosis and prognosis of this complaint. On the other hand, the elucidation of the pathogenesis has meant no material advance in the therapy, apart from the use of Rh‐negative blood in transfusions to children with this disease. Judging from his own material, the author considers this improvement of the transfusion therapy to imply only a very modest step forward in the results of our treatmentGuiding‐lines are given for practical experiments to find a protective substance against the haemolytic action of the Rh antibodies in the child's body. It is preliminarily stated that a certain effect of this kind might possibly be ascribed to progesterone. The risk of contracting morbus haemolyticus neonatorum is not decreased for children taken from Rh‐immunised women by means of a caesarean section before the onset of labour, not even if this is done several weeks before term.
Über D‐Vitamingehalt der Renntiermilch
Authors: GEZELIUS GÖRAN 
Published: January 2008

Zusammenfassung.Verf. vertritt die Ansicht, dass die fettreiche Renntiermilch eine D‐Vitaminquelle für die Lappen darstellte, und dass sie diese früher gewissenhafter ausnutzten. Untersuchung der Renntiermilch auf ihren D‐Vitamingehalt hat gezeigt, dass sie ungefähr ebensoviel D‐Vitamin enthält wie Kuhbutter im SommerSummary.The author has assumed that the Lapps, in their reindeer milk which is so rich in fat, have had access to a source of D‐vitamines which they have hitherto most carefully utilized. Tests of reindeer milk, in respect to its percentage of D‐vitamines, have shown, too, that it contains about as great a percentage of D‐vitamines as cow's milk in the summerRésumé.L'auteur a supposé que les Lapons ont trouvé dans le lait de renne, riche en graisse, une source de vitamines D dont ils ont auparavant tiré profit avec plus de soin. L'examen du lait de renne quant à sa teneur en vitamines D a aussi prouvé que ce lait contient à peu près autant de vitamins D que le beurre de vache en été.