Silicate mineralogy of basalts at DSDP Leg 54 Holes

Basalts drilled from the East Pacific Rise, OCP Ridge, and Siqueiros fracture zone during Leg 54 are texturally diverse. Dolerites are equigranular at Sites 422 and 428 and porphyritic, with phenocrysts of plagioclase (An69.73) and Ca-rich clinopyroxene (Ca42Mg48Fe10) at Site 427. The East Pacific Rise lavas and some of those from the OCP Ridge are fine-grained and porphyritic. The majority of the large crystals are clustered skeletal glomerocrysts of plagioclase An64-77), together with olivine (Fo80-87), Ca-rich clinopyroxene, or both. Euhedral phenocrysts of plagioclase, together with olivine, Carich clinopyroxene, and Cr-Al spinel in some cases, occur in most of the fine-grained lavas. These phenocrysts are small (maximum dimension <1 mm in all but one sample), sparse (combined modal amount <1% in all samples), and distinctive from the megacrysts which characterize many ocean-floor lavas. In two East Pacific Rise lavas, zoned plagioclase (An83 cores) is the sole phenocryst phase. In other porphyritic lavas from all the main East Pacific Rise and OCP Ridge units drilled during Leg 54, the plagioclase phenocrysts contain cores of bytownite (An79-87) surrounded by more-sodic feldspar (An67-77). Core/rim relationships vary from continuous normal zoning, through discontinuous zoning, to extensive resorption of the calcic cores in some samples. The compositions of the plagioclase calcic cores are systematically related to those of the glomerophyric plagioclase and olivine in the lavas containing them. Furthermore, only one compositional population of calcic cores occurs in each rock. The possible causes of these relationships are far from clear. Magma mixing, although superficially applicable, is inconsistent with important aspects of the phenocryst mineralogy of these particular lavas. A more satisfactory model to explain both phenocryst zoning and rapid glomerocryst growth immediately before extrusion may be constructed by postulating influx of water into the upwelling magmas within Layer 3 of the oceanic crust beneath the East Pacific Rise, and subsequent loss of part of this water during effervescence within feeder dykes between Layer 3 and the ocean floor. It is shown that this model is fully consistent with published data on water and carbon dioxide contents and ratios in the pillow-margin glasses, vesicles, and phenocryst inclusions of ocean-floor basalts. The evidence for the precipitation of plagioclase- dominated crystalline assemblages from these magmas in the upper part of Layer 3 is concordant with recent geophysically based modeling of the structure of the East Pacific Rise. Calcium-rich clinopyroxenes in dolerites from the OCP Ridge and Siqueiros fracture zone show radial, oscillatory, and sector-zoning. In Sample 428A-5-2 (Piece 5a), the compositional trends resulting from this zoning closely resemble those of the pyroxenes in some lunar lavas. The controls on crystallization of interstitial pigeonite - epitaxial upon augite - in this rock are discussed. Both sector-zoning of the augite and nucleation of pigeonite within microvolumes of magma with a low Ca(Mg + Fe) ratio appear to be important factors.

Spatiotemporal patterns in community structure of macroinvertebrates inhabiting calcareous periphyton mats

Calcareous floating periphyton mats in the southern Everglades provide habitat for a diverse macroinvertebrate community that has not been well characterized. Our study described this community in an oligotrophic marsh, compared it with the macroinvertebrate community associated with adjacent epiphytic algae attached to macrophytes in the water column, and detected spatial patterns in density and community structure. The floating periphyton mat (floating mat) and epiphytic algae in the water column (submerged epiphyton) were sampled at 4 sites (1 km apart) in northern Shark River Slough, Everglades National Park (ENP), in the early (July) and late (November) wet season. Two perpendicular 90-m transects were established at each site and 100 samples were taken in a nested design. Sites were located in wet-prairie spikerush-dominated sloughs with similar water depths and emergent macrophyte communities. Floating mats were sampled by taking cores (6-cm diameter) that were sorted under magnification to enumerate infauna retained on a 250-μm-mesh sieve and with a maximum dimension >1 mm. Our results showed that floating mats provide habitat for a macroinvertebrate community with higher densities (no. animals/g ash-free dry mass) of Hyalella azteca, Dasyhelea spp., and Cladocera, and lower densities of Chironomidae and Planorbella spp. than communities associated with submerged epiphyton. Densities of the most common taxa increased 3× to 15× from early to late wet season, and community differences between the 2 habitat types became more pronounced. Floating-mat coverage and estimated floating-mat biomass increased 20 to 30% and 30 to 110%, respectively, at most sites in the late wet season. Some intersite variation was observed in individual taxa, but no consistent spatial pattern in any taxon was detected at any scale (from 0.2 m to 3 km). Floating mats and their resident macroinvertebrate communities are important components in the Everglades food web. This community should be included in environmental monitoring programs because degradation and eventual loss of the calcareous periphyton mat is associated with P enrichment in this ecosystem.

La systématisation du travail social : Le cas de L'Évaluation-Orientation en protection de la jeunesse au Centre de services sociaux Laurentides-Lanaudière

La toile de fond de notre essai est la transformation du travail social depuis dix (10) ou quinze (15) ans au Québec. Cette transformation est un phénomène inégal suivant les secteurs de travail. Nous l'observons, nous, en Protection de la jeunesse seulement, secteur où elle a été la plus rapide, la plus vive. Secteur aussi qui serait comme un phare pour les autres. C'est aussi un phénomène global et complexe. Il y a des dimensions technocratique [gestion des populations à risques, évaluation épidémiologique, décision centralisée...), juridique [accessibilité à la justice, changements dans les pouvoirs du juge, les Chartes des droits de la personne...), et idéologique [statuts social de l'enfance, primauté de la santé...). Ne pouvant tout aborder dans cet essai nous considérerons deux (2) dimensions qui, ensemble, constitue une systématisation du travail social. La dimension 1: l'institutionnalisation fine du contrôle social sur des situations dites de «protection» et; la dimension 2 la rationalisation du travail concret ou gestion formalisée des opérations. Compte tenu des limites de notre travail, nous ne traiterons pas ces deux (2) dimensions avec une égale énergie. Pour la dimension 1 nous reprendrons les résultats d'autres recherches et nous nous attarderons particulièrement à la dimension 2 en présentant le mouvement de rationalisation dit «Rapport Harvey» et en analysant plus en détail encore son mode d'implantation et ses effets quant à un sous-programme [i.e. l'évaluation-orientation] dans un centre de services sociaux. Avant le Rapport Harvey, il y a eu la mise en oeuvre de la Loi sur la protection de la jeunesse, une «nouvelle façon» de protéger les enfants qu'on appelle institutionnalisation de la Protection de la jeunesse (Chapitre II). Cette institutionnalisation continue comme processus socio-judiciaire global [à preuve Rapport Bouchard et Jasmin aujourd'hui). Quant à nous nous en considérons seulement un aspect particulier: le travail concret ou la définition fine et la mise en forme des opérations. Le tout commence avec la demande du Ministère des services de santé et des services sociaux à un spécialiste en «gestion des opérations».

Estudo das qualidades psicométricas do questionário de cooperação organizacional (QCO)

O presente estudo apresenta as qualidades psicométricas do Questionário de Cooperação Organizacional (QCO). A amostra é constituída por 300 funcionários camarários, dos departamentos de Atendimento e Urbanismo, de 70 Câmaras Municipais de Portugal Continental. Recorreu-se a procedimentos de Análise Factorial Exploratória, método de Máxima Verosimilhança, Scree Test, com método de rotação Varimax with Kaiser Normalization. Os resultados demonstram que o QCO é capaz de medir 3 dimensões da cooperação organizacional, explicando 49,36% da variância total. Os valores de consistência interna foram bastante satisfatórios, com a dimensão 1 “Cooperação configurada por regulamentações formais" a apresentar um Alpha de Cronbach de 0,875, a dimensão 2, "Cooperação decorrente da interdependência de indivíduos únicos articulados entre si" com 0,864 e a dimensão 3 "Cooperação através da orientação para a sociedade dos contributos singulares" com 0,787. /ABSTRACT: This study presents the analysis of psychometric properties of the Questionário de Cooperação Organizacional (QCO) (Organizational Cooperation Questionnaire). lt was applied to a sample of 300 employees from the Reception and Urbanization departments of 70 continental portuguese town-halls. Procedures of Exploratory Factorial Analysis, Maximum Likelihood extraction method and Varimax with Kaiser Normalization rotation method were performed. Results indicate that the QCO is capable of measuring 3 organizational cooperation dimensions, which explain 49,36% of the total variance. Reliability statistics were very satisfactory, in which dimension 1 "Cooperation structured by formal regulamentation" has a Cronbach's Alpha of 0,875, dimension 2, "The cooperation originated from the interdependence by the articulation amongst unique individuals" 0,864, and dimension 3 "Orientation to society of singular contribution through cooperation" 0,787.

Hausdorff dimension bounds for smoothness of holonomies for codimension 1 hyperbolic dynamics

We prove that the stable holonomies of a proper codimension 1 attractor Λ, for a Cr diffeomorphism f of a surface, are not C1+θ for θ greater than the Hausdorff dimension of the stable leaves of f intersected with Λ. To prove this result we show that there are no diffeomorphisms of surfaces, with a proper codimension 1 attractor, that are affine on a neighbourhood of the attractor and have affine stable holonomies on the attractor.

Hopf bifurcation for degenerate singular points of multiplicity 2n-1 in dimension 3

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Algebraische Zyklen auf abelschen Varietäten der Dimension 4 mit Polarisierung von Typ (1,2,2,2)

Diese Arbeit besch"aftigt sich mit algebraischen Zyklen auf komplexen abelschen Variet"aten der Dimension 4. Ziel der Arbeit ist ein nicht-triviales Element in $Griff^{3,2}(A^4)$ zu konstruieren. Hier bezeichnet $A^4$ die emph{generische} abelsche Variet"at der Dimension 4 mit Polarisierung von Typ $(1,2,2,2)$. Die ersten drei Kapitel sind eine Wiederholung von elementaren Definitionen und Begriffen und daher eine Festlegung der Notation. In diesen erinnern wir an elementare Eigenschaften der von Saito definierten Filtrierungen $F_S$ und $Z$ auf den Chowgruppen (vgl. cite{Sa0} und cite{Sa}). Wir wiederholen auch eine Beziehung zwischen der $F_S$-Filtrierung und der Zerlegung von Beauville der Chowgruppen (vgl. cite{Be2} und cite{DeMu}), welche aus cite{Mu} stammt. Die wichtigsten Begriffe in diesem Teil sind die emph{h"ohere Griffiths' Gruppen} und die emph{infinitesimalen Invarianten h"oherer Ordnung}. Dann besch"aftigen wir uns mit emph{verallgemeinerten Prym-Variet"aten} bez"uglich $(2:1)$ "Uberlagerungen von Kurven. Wir geben ihre Konstruktion und wichtige geometrische Eigenschaften und berechnen den Typ ihrer Polarisierung. Kapitel ref{p-moduli} enth"alt ein Resultat aus cite{BCV} "uber die Dominanz der Abbildung $p(3,2):mathcal R(3,2)longrightarrow mathcal A_4(1,2,2,2)$. Dieses Resultat ist von Relevanz f"ur uns, weil es besagt, dass die generische abelsche Variet"at der Dimension 4 mit Polarisierung von Typ $(1,2,2,2)$ eine verallgemeinerte Prym-Variet"at bez"uglich eine $(2:1)$ "Uberlagerung einer Kurve vom Geschlecht $7$ "uber eine Kurve vom Geschlecht $3$ ist. Der zweite Teil der Dissertation ist die eigentliche Arbeit und ist auf folgende Weise strukturiert: Kapitel ref{Deg} enth"alt die Konstruktion der Degeneration von $A^4$. Das bedeutet, dass wir in diesem Kapitel eine Familie $Xlongrightarrow S$ von verallgemeinerten Prym-Variet"aten konstruieren, sodass die klassifizierende Abbildung $Slongrightarrow mathcal A_4(1,2,2,2)$ dominant ist. Desweiteren wird ein relativer Zykel $Y/S$ auf $X/S$ konstruiert zusammen mit einer Untervariet"at $Tsubset S$, sodass wir eine explizite Beschreibung der Einbettung $Yvert _Thookrightarrow Xvert _T$ angeben k"onnen. Das letzte und wichtigste Kapitel enth"ahlt Folgendes: Wir beweisen dass, die emph{ infinitesimale Invariante zweiter Ordnung} $delta _2(alpha)$ von $alpha$ nicht trivial ist. Hier bezeichnet $alpha$ die Komponente von $Y$ in $Ch^3_{(2)}(X/S)$ unter der Beauville-Zerlegung. Damit und mit Hilfe der Ergebnissen aus Kapitel ref{Cohm} k"onnen wir zeigen, dass [ 0neq [alpha ] in Griff ^{3,2}(X/S) . ] Wir k"onnen diese Aussage verfeinern und zeigen (vgl. Theorem ref{a4}) begin{theorem}label{maintheorem} F"ur $sin S$ generisch gilt [ 0neq [alpha _s ]in Griff ^{3,2}(A^4) , ] wobei $A^4$ die generische abelsche Variet"at der Dimension $4$ mit Polarisierung vom Typ $(1,2,2,2)$ ist. end{theorem}

Tab. 1: Approximate dimension of the pingos

A group of nine pingos occurs in the valley of a glacial meltwater river. The pingos rise from a plain of low-center polygons. Some pingos have a typical cone shape, but others are linear, apparently centered on ice wedges . The occurrence of most pingos at the junction of oversize ice wedge polygon ridges suggests that the injection of water and the segregation of ice occurred along pathways provided by the ice wedges.

Submanifolds of dimension n-1 in [epsilon]n̳ with normals satisfying a Lipschitz condition.

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Dimension stone for building facades: methodology for structural design

The importance of a careful selection of rocks used in building facade cladding is highlighted. A simple and viable methodology for the structural detailing of dimension stones and the verification of the global performance is presented based on a Strap software simulation. The results obtained proved the applicability of the proposed structural dimensioning methodology which represents an excellent simple tool for dimensioning rock slabs used for building facade cladding. The Strap software satisfactorily simulated the structural conditions of the stone slabs under the studied conditions, allowing the determination of alternative slab dimensions and the verification of the cladding strength at the support.