bluuebunny/crossref_metadata_2025_split huggingface dataset:
Heavy metal pollution status in the Malaysian aquatic environment
Authors: Shazili Noor Azhar M. , Yunus Kamaruzaman , Ahmad Ahmad Shamsudin , Abdullah Norantonina , Rashid Mohd Kamil Abd 
Published: June 2006

The objective of this paper was to review the status of the Malaysian aquatic environment with respect to heavy metals. Much of the work on metals focused on measurements in biota and sediments, but very little research has been done on dissolved and particulate metals in water, metal speciation in sediments or on the bioavailability of metals. Cadmium (Cd), Copper (Cu), Lead (Pb) and Zinc (Zn) received much attention but due to technical difficulties, Arsenic, (As), Mercury (Hg), Tin (Sn) and other hydride elements have not been well studied.
The sources of metal pollution come from manufacturing, agriculture, sewage and motor vehicle emissions. The few reliable studies on metals in water indicate that some rivers were contaminated with Pb, Cu and Zn. Measurements in fish, bivalves and shrimp indicate no contamination of these resources by metals. However contamination by Cd and Pb was noted in some littoral shore molluscs such as Thais sp. as well as rock oysters (Saccostrea sp.) which may be due to non-anthropogenic sources.
Sediments of the Juru and Langat rivers are contaminated by Pb and Zn, while the Langat River was heavily contaminated by Cd. The concentrations of Zn and Pb in coastal sediments off Juru in Penang, and in the Johor Strait were two and three times higher than global shale values. The source of Pb pollution was thought to be derived from the use of leaded petrol. Metal levels in sediments of the Malacca Strait and the South China Sea were generally similar to global shale values.
Growth factor attenuation of IFNγ‐mediated hepatocyte apoptosis requires p21waf−1
Authors: McCullough Christian T. , Tura Benjamin J. , Harrison David J. 
Published: June 2006

SummaryInterferon gamma (IFNγ) is an important mediator of inflammatory liver damage as part of a complex cytokine network. In vitro, IFNγ induces hepatocyte apoptosis. We hypothesized that the hepatocyte response to IFN signalling is context‐dependent, and that specific growth factors, via phosphatidylinositol 3 kinase (PI(3)K) and protein kinase B/Akt signalling pathways, confer a cytoprotective effect. We established an in vitro model of IFNγ‐mediated primary hepatocyte injury. We show that epidermal growth factor (EGF) and hepatocyte growth factor (HGF) attenuate the IFNγ‐induced hepatocyte apoptosis. IRF‐1, but not p53, is required for IFNγ‐mediated apoptosis. The loss of p21waf−1 not only sensitizes the hepatocyte to IFNγ‐mediated injury but is required for survival factor mediated cytoprotection. We show that the PI(3)K inhibitor, LY294002, partially inhibits the apoptotic response of the hepatocyte to IFNγ. In summary, we present evidence that a component of pro‐apoptotic IFNγ signalling in the primary hepatocyte occurs via the PI(3)K pathway. We show that the hepatocyte response to IFNγ is modulated by external survival factors and that this survival signalling requires p21waf−1.
RECENT SEDIMENTARY HISTORY OF ST. JOSEPH BAY, FLORIDA1
Authors: STEWART RICHARD A. , GORSLINE DONN S. 
Published: June 2006

SUMMARYThe history of St. Joseph Bay, on the west coast of Florida, begins with the last rise in sea level about 5,000 years ago. The formation of an extensive cuspate spit has formed a basin which is now in the process of being filled by detrital sands delivered via longshore drift from the eastern Apalachicola River. Prior to or during early stages of spit development, a wedge of fine material was deposited over the old terrace surface from an old distributary of the Apalachicola. Present sedimentation has as yet failed to obscure portions of this older surface within the lagoon.Clean quartz sand and biological carbonates comprise the bulk of the present sediment contribution. The typical East Gulf “kyanite‐staurolite” heavy mineral suite is present, as is the kaolinite‐montmorillonite‐illite clay mineral suite common to this coast.Sediments in this area have an average organic content of about 1.4%. A high organic carbon/organic nitrogen average of 15.4 has resulted from the accumulation of highly carbonaceo us plant debris under the restrictive environment of the lagoon.
MINOR STRUCTURES OF UNCONSOLIDATED MARINE SEDIMENTS REVEALED BY X‐RADIOGRAPHY1
Authors: CALVERT S. E. , VEEVERS J. J. 
Published: June 2006

SUMMARYHamblin's (1962) X‐radiographic technique for examining the minor structures of sandstone and siltstone is applied to the study of structures in cores of unconsolidated sediments. The technique is capable of revealing particles not visible on the surface of the core, of resolving structures poorly defined in reflected light, and of revealing latent structures in apparently homogeneous sediments.
POROSITÄT UND VERDICHTUNG REZENTER, MARINER SEDIMENTE
Authors: FÜCHTBAUER HANS , REINECK HANS‐ERICH 
Published: June 2006

SUMMARYSand and clay porosities of foreshore, tidal flat, and shallow sea sediments from the southern North Sea were determined. No definite relationship could be observed between porosity, condensation ratio, and depositional environment.Porosity increases with increasing clay content. The clay porosity probably depends to some degree on the rate of sedimentation. The porosity of experimentally deposited sands increases with decreasing grain size. The same relation can be observed with fossil sandstones. In Recent sands, this increase may be compensated by a closer packing arrangement of the finer grains, expressed by a higher condensation ratio
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(P= natural porosity, Pw and Pd are the porosities of the loosest and closest arrangements under water, respectively).Under certain conditions, the sand(stone) porosity decreases continuously with increasing depth (Fig. 7).
LES REMPLISSAGES KARSTIQUES
Authors: BONTE A. 
Published: June 2006

SUMMARYKarst depressions are filled (or lined), at least in the first stages of their development, with material subsiding from permeable deposits that cover the carbonate rocks. Without such a cover no depressions can be formed. In the case of very impure limestones, the fill of the depressions consists for a great part of the insoluble residue from these limestones.Simultaneously with the morphological evolution of the depressions, their fillings also undergo important changes. The evolution terminates with a denuded karst. The solution processes may be re‐activated if the surface is covered by new (allochthonous) sedimentary material.
UN CURIEUX PHÉNOMÈNE D'ÉROSION FAMENNIENNE: LES “PAINS DE GRÈS” DE CHAMBRALLES (ARDENNE BELGE)
Authors: ET C. EK P. MACAR 
Published: June 2006

SUMMARYVertical walls in quarries of Famennian sandstones near Aywaille (Belgian Ardennes) show in abundance varied sedimentary structures. The most interesting are undoubtedly erosional effects on a few islets (or promontories) of a former sandstone layer that are bordered in several places by microcliffs. Rounded and sub‐circular “wash‐loaves” accompanied by smaller and less regular masses occur near and outside of these cliffs; these are so numerous at one place that they appear as a swarm. Both types are remnants of the islets; they sometimes stand as micro‐stacks, but are also sometimes dragged away some distance, as revealed by the inclined or even vertical laminae that some show in cross‐section. We think that the carving of the microcliffs does not denote an important contemporaneous consolidation of the bed, although its limestone content may have favored firmness. We assume that it is mostly a question of the amount of water in the wet sand. Other examples of microcliffs in ancient formations are known in the vicinity; the swarm of stacks and wash‐debris, on the other hand, seems an exceptional phenomenon.
PETROGENESIS AND PALAEOENVIRONMENT OF DEVONIAN ALGAL LIMESTONES OF NEW SOUTH WALES
Authors: WOLF KARL H. 
Published: June 2006

SUMMARYA Lower Devonian algal reef complex, with a basinal algal turbidite facies, offers excellently preserved autochthonous and allochthonous algal textures and structures of the following types: algal calcilutite biolithites of dense, grumous, cellular, tubular, “pelletoid” and “granuloid” textures, algal calcilutite crusts and algal‐bound detritus (e.g., stromatolites), algal pisolites, oolites and circumcrusts, algal pellets and grains (in contrast to faecal and bahamite types), colonial and stem fragments, algal filaments and cells, stromatactis and birdseyes. Encrusting Foraminifera and stromatoporoid colonies were of very subordinate importance in forming the turbulent‐water reefs. Protected pools, crevices, and local lagoons offered a favourable niche for calm‐water Codiaceae, crinoids, polyzoans, Amphipora and some molluscs. Corals occur rarely.The wave‐resistant calcilutite reefs as well as the high percentage of subsequently introduced fine “internal sediments” within the limestone‐frameworks, indicate that grain‐matrix‐cement ratios do not necessarily reflect degree of turbulence and winnowing.The algal reefs have no effective primary porosity. Channels and cavities, predominantly horizontally oriented, were filled with internal sediments and early‐formed sparite cement.Fibrous calcite cement is confined to limestones that seem to have formed in a littoral environment whereas granular sparite appears to be an intra‐stratal product of a later stage.
ASPECTS OF CALCIUM CARBONATE DEPOSITION IN GREAT ONYX CAVE, KENTUCKY1
Authors: SIEGEL FREDERIC R. 
Published: June 2006

SUMMARYSpeleothems of Great Onyx Cave, Kentucky, are composed of calcite, aragonite, and gypsum. Calcite is present in all carbonate samples, and where aragonite is also present, the speleothem core is always of calcite, overlain by a progression of alter‐ nating shells of aragonite and calcite, calcite being the outermost carbonate shell. In some specimens, gypsum encrusts these other two phases but is never itself enclosed by a carbonate, thus demonstrating that carbonate deposition was complete in these specimens before sulfate deposition began.Cave temperature is constant at 12.5°C. The pH‐values of standing and dripping water ranged from 7.5 to 8.7, with the value of 8.7 being recorded where precipitation and crystallization of calcite was taking place. At a pH of 8.7, some authors consider that calcium carbonate should normally crystallize as aragonite, but in the cave studied, pH seems to have little effect and temperature may be the controlling factor.Strontium is measurable in most of the aragonite‐bearing samples and not in the calcite ones. But two calcite stalactites and separated calcitic portions of mixed aragonite‐calcite stalactites contain considerable quantities of strontium. Although the affinity of strontium for the aragonite lattice is demonstrated, it is probable that in these cave deposits, the strontium did not have a primary influence on the poly‐ morph which crystallized.
FLUVIATILE SEDIMENTARY STRUCTURES IN THE WOOD BAY SERIES (DEVONIAN) OF SPITSBERGEN
Authors: FRIEND P. F. 
Published: June 2006

SUMMARYA noteworthy feature of parts of the Series is the development of cyclothems which consist of: scoured surface, coarse member, fine member, scoured surface. General environments, suggested by this and fossil evidence, are: erosion in river bed, deposition in river bed, deposition in overbank area, erosion in river bed. Structures within the sets of strata include: no lamination, flat bedding, small and large‐scale cross‐lamination, parting lineation. The significance of each is discussed. Sole structures, occurring on the scoured surfaces, are described. They include: groove casts, crescents, flute casts, a variety of long welts, and unoriented structures. These are mainly scour structures but some may be subaerial marks, and there is also evidence for post‐depositional flowage. The value of these structures as indicators of palaeocurrent and ultimately palaeoslope directions is discussed with examples. Measurements of sole structures, parting lineations and ripples have been more profitable than large‐scale cross‐stratification or contorted lamination.
CROSS‐BEDDING IN THE MERIDIAN SAND
Authors: WERMUND E. G. 
Published: June 2006

SUMMARYThe Meridian Sand is recognized as neritic bar sand because it is overlain and underlain by prodominantly marine strata, contains a marine microfauna and is glauconitic. Cross‐bedding is the large scale planar type and has a regional variance of 10,302. No maximum is present where dip azimuths of sets are plotted on a stereogram. It is suggested that the wave path, topography of the depositional surface, and local rates of subsidence varied during deposition of the cross‐bedded sand resulting in a uniform distribution of the cross‐bedding sets.
CONVOLUTE LAMINATION AND OTHER STRUCTURES FROM THE LOWER COAL MEASURES OF YORKSHIRE
Authors: DAVIES HUW G. 
Published: June 2006

SUMMARYSeveral deformational sedimentary structures are recorded from the non‐marine sandstones of the Lower Coal Measures of Yorkshire. Some of these structures may be termed convolute lamination and for others the term corrugated lamination is proposed. The scope and synonyms of convolute lamination are discussed and both terms are defined and illustrated. The essential difference between convolute lamination and corrugated lamination is the absence of an overall anticline‐syncline morphology in the latter. Rupture of lamination through most of the thickness of the deformed horizons give rise to rupture structures.A petrological investigation of the sediments showed slight variations in both grain size and mineralogy within individually deformed horizons. The structures are considered to be the result of load casting, caused by heterogeneity of the sediment, and/or thixotropic behaviour.
A CLASSIFICATION OF SUBAQUEOUS SEDIMENTARY STRUCTURES BASED ON RHEOLOGICAL AND KINEMATICAL PARAMETERS
Authors: ELLIOTT R. E. 
Published: June 2006

SUMMARYA wide range of subaqueous sedimentary structures is classified according to the behaviour of sediments at the time of formation of the structures and according to the nature of the motions to which these sediments are subject at that time. Assessments of sediment behaviour and nature of motions are given for each group of structures. The principles and elemental bases of the classification are discussed and its advantages are briefly stated.
SEDIMENTSTRUKTUREN AUS DEN NIEDERRHEINISCHEN BRAUNKOHLENSCHICHTEN DES MIOZÄNS
Authors: UND K. L. GAURI , KALTERHERBERG J. 
Published: June 2006

SUMMARYSedimentary structures in the Miocene fluviatile deposits of the Lower Rhine Basin, lying immediately beneath the lignite formations have been studied at Tagebau Frechen near Cologne. The structures investigated include slump structures, load casts, clay breccia, cross‐bedding, sand fabric and orientation of driftwood.The slump structures are composed of alternating laminae of clay and silt and have resulted from sub‐aquatic sliding of a sedimentary sheet over a surface of erosion or of a foreset bed of 10–20° inclination. The slumping has caused folding or brecciation of the strata involved.The base of a sand bed is difficult to obtain as the sediment is weakly consolidated. Load casts, therefore, have been studied exclusively in their internal structure. It is considered that the load casts of smaller dimensions have suffered a diminution of relief through settlement after the process of load casting had ceased.Two types of clay breccia have been recognised, namely those which have undergone erosion and transportation by water and those which have resulted from slumping.In an exposure, tabular‐ and trough‐type of cross‐bedding alternate with each other in geological succession. From these examples sand fabrics have been studied. Both in tabular‐ and trough‐type of cross‐bedding the apparent long axes show two maxima. In the former case, these maxima are disposed to each other at an acute angle, in the latter case, however, they are perpendicular to each other. Imbrication, after tilting the Sf‐to original position, is down‐current in tabular cross‐bedding. In trough type, on the contrary, it may be upcurrent or the long axes of the grains dip symmetrically in up‐ and down‐current direction.
STRUCTURES OF DUNES AT WHITE SANDS NATIONAL MONUMENT, NEW MEXICO (AND A COMPARISON WITH STRUCTURES OF DUNES FROM OTHER SELECTED AREAS)1
Authors: McKEE EDWIN D. 
Published: June 2006

SUMMARYThe type, scale, and relative abundance of sedimentary structures in four kinds of dunes at White Sands National Monument, New Mexico, were determined by examination of vertical sections on walls of trenches cut through the dunes both in a windward direction and at right angles to this direction. Analysis of cross‐stratification in all dunes examined indicated certain common features: sets of cross‐strata mostly are medium‐ to large‐scale; nearly all laminae dip downwind at high angles (not uncommonly at 30°‐34°); most bounding surfaces between sets of cross‐strata are nearly horizontal on the upwind side, but have progressively steeper dips to lee, downwind; and individual sets of cross‐strata tend to be thinner and the laminae flatter near the top than at the bottom of a dune in vertical section.Sparse but distinctive structural features that are characteristic of the four types of dunes are varieties of contorted bedding, rare ripple laminae, and either local scour‐and‐fill bedding, or festoon bedding. Other structures, apparently limited to either one or two types of dunes, are the concave‐downward foresets in some parabolic dunes; the low‐angle reverse dips of upwind strata on high transverse dunes; and the almost horizontal laminae which represent apparent dip in sections normal to wind direction in dome‐shaped and transverse dunes.Describing cross‐stratification in terms of three dimensions, dune structure at White Sands consists dominantly of the tabular planar sets, with units thickest near the dune base, thinner above. To a lesser extent the sets are of simple (non‐erosion) tabular form and relatively uncommonly, of the trough type. Wedge planar forms are scarce. The planar forms characteristically are of two classes in nearly equal proportions: those in which bounding surfaces are virtually horizontal and those in which they dip at moderate to high degree.A brief comparison is made between the structures of dunes that are characteristic of one effective wind direction, as at White Sands, and certain others formed by winds of two or more directions. Seif dunes of Libya, reversing dunes of the San Luis Valley, Colorado, and star dunes in Saudi Arabia are discussed as examples of complex dunes formed by multi‐directional winds.
AIR AND SAND MOVEMENTS TO THE LEE OF DUNES1
Authors: HOYT JOHN H. 
Published: June 2006

SUMMARYThe large and extensive transverse and barchane dunes of coastal South West Africa are strongly oriented under the influence of predominantly southerly winds. During periods of strong winds (40–50 miles/h) deposition occurs on the lee slope in three ways: (1) sand is blown over the crest of the dune and falls on the lee slope; (2) rapid deposition near the dune crest results in periodic slumps and slides down the lee slope; (3) eddy currents developed to the lee of the dune pick up sand from the surface downwind from the dune and transport it to the lee slope.The size and strength of the lee eddy is surprising. With winds in the 40–50 miles/h range frequent gusts lift fine sand from the downwind surface to a height of several feet. Less frequently sand is picked up from a low position on the lee slope and redeposited higher on the slope. The addition of material to the lee slope by the eddy is much less volumetrically than the contribution directly over the dune crest from the windward direction; however, with strong winds the removal and transportation of sand from the area downwind of the lee slope back to the lee slope appears to be important in the deflation of this surface. The width of the area influenced by the lee eddy during strong winds is about equal to the height of the dune.Observations in low dunes from 1 to 20 ft. high at Sapelo Island, Ga., U.S.A., confirm the presence of a well developed eddy to the lee of these dunes during strong and moderate winds (20–50 miles/h).
AN UNUSUAL SEDIMENTARY STRUCTURE INDICATIVE OF SHALLOW WATER CONDITIONS IN THE GRÈS ARMORICAIN OF FINISTÈRE (FRANCE)
Authors: BRADSHAW J. D. 
Published: June 2006

SUMMARYThe communication describes dome‐like masses of sand apparently developed by gully erosion on the upper surfaces of Ordovician sandstones. The similarity of these structures to the minor topography of tidal marshes is noted, and it is suggested that similar processes may be responsible.
SEDIMENT SIZE DISTRIBUTION PROFILE ON THE CONTINENTAL SHELF OFF NEW JERSEY1
Authors: DONAHUE JESSIE G. , ALLEN ROBERT C. , HEEZEN BRUCE C. 
Published: June 2006

SUMMARYA series of samples from the continental shelf off New Jersey reveals a continuous surface layer of fine sand overlying a variety of sediment type. Ripples and shell debris suggest the fine sand is reworked and is in adjustment with the present shelf environment.
THE ANGLE OF REPOSE FOR A SINGLE GRAIN ON A FIXED ROUGH BED
Authors: MILLER ROBERT L. , BYRNE ROBERT J. 
Published: June 2006

SUMMARYThe angle of repose under water is experimentally determined for a single particle on a fixed rough bed.The effect of grain shape, size and sorting of the bed and ratio of particle diameter to average bed grain diameter are taken into account. An empirical equation is given for predicting angle of repose as a function of the above factors. The accuracy of fit of this equation is quite good. Several other conclusions drawn for the case of a single grain on a fixed rough bed are:

Angle of repose increases with decrease in size, departure from sphericity and increased angularity.
Angle of repose increase with decrease in sorting.
A single angle of repose for sand size grains is not valid. Variation ranges from nearly 90° to less than 20°, depending on the values of the factors given above.
THE STUDY OF ARENACEOUS SEDIMENTS BY MEANS OF ACETATE REPLICAS
Authors: BJØRLYKKE KNUT 
Published: June 2006

SUMMARYThe present paper describes the use of cellulose acetate replicas in the study of silicate rocks, particularly indurated sandstones. The procedure of Boardman and Utgaard (1964) for the reproduction of surface structures of polished limestone slabs for the study of Paleozoic Bryozoa, was modified and applied on silicate rocks using HF instead of formic acid as the etching agent.The polished slabs are etched with 40 % HF for 5–10 seconds and then washed, dried, wetted with acetone and gently pressed towards a mount of cellulose acetate. After drying, the specimen is quickly removed and an imprint is left on the acetate peel. By using thick (1.6 mm) cellulose acetate sheets no mounting on glass slides is needed, and the replica can be studied directly under the microscope or be used as a photographic negative.
THE PRESENTATION OF SUBJECTIVE SHAPE AND ROUNDNESS DATA
Authors: SMALLEY I. J. 
Published: June 2006

SUMMARYIf a modified version of the Zingg system is used particles can be subjectively classified into four shape classes. The roundness of a particle can be estimated by assessing the flat/convex/concave ratio and can then be represented as a point on a triangular net; this point can also indicate the Zingg class of the particle.
COMPARATIVE STUDY OF DEVIATION INDEX Hqa, Qd AND So
Authors: POMEROL CHARLES 
Published: June 2006

SUMMARYThe deviation index Hqa is studied by use of the A.F.N.O.R. set of sieves (the geometrical progression of mesh‐size has a ratio 1010 # 1.259). The author shows the connection between Hqa and the sorting index (So) of Trask, and the connection between Hqa and the Qdφ index of Krumbein (Hq= 3 Qdφ, approximately).