bluuebunny/crossref_metadata_2025 huggingface dataset:
Semi‐quantitative analysis of telomerase activity in exfoliated human urothelial cells and bladder transitional cell carcinoma
Authors: Yokota K. , Kanda K. , Inoue Y. , Kanayama H. , Kagawa S.
Published: June 2006

Objective

 To determine the utility of detecting telomerase activity in transitional cell bladder cancer, using the telomeric repeat amplification protocol (TRAP) assay, and thus provide a test for the detection and monitoring of bladder cancer, especially low‐grade tumours.

Patients, subjects and methods

 Telomerase activity was assayed in bladder cancer tissues and the exfoliated urothelial cells from 29 patients with bladder cancer, 10 with benign disease, and in 10 healthy subjects using the TRAP assay. The levels were assessed semi‐quantitatively by calculating the ratio to an internal telomerase assay standard.

Results

 Telomerase activity was very low in the exfoliated urothelial cells from all healthy subjects and patients with benign disease, with a mean (sd) ratio of 0.25 (0.03) and 0.33 (0.04), respectively. A threshold ratio of 0.4 was calculated as the mean+2 sd of the telomerase activity level of the exfoliated urothelial cells from patients with benign disease. Using this threshold, telomerase activity was negative in exfoliated urothelial cells from all benign cases (100% specificity) and positive in all 26 bladder cancer tissue samples assayed. In tumour tissue, telomerase activity was not associated with tumour grade, size or stage. Telomerase activity in exfoliated urothelial cells from patients with bladder cancer was positive in 25 of 29 samples (86% sensitivity). The sensitivity of telomerase activity in exfoliated cells was seven of nine in G1, 10 of 12 in G2 and all eight G3 tumours; the corresponding sensitivity for voided urine cytology in G1, G2 and G3 tumours was two of nine, six of 12 and six of eight, respectively.

Conclusion

 These results indicate that telomerase activation occurs as an early step in carcinogenesis and the semi‐quantitative analysis of telomerase activity in exfoliated urothelial cells could be a minimally invasive and useful method for detecting bladder cancer, even in low‐grade tumours.
Effect of nuclear elastic scattering on ion heating characteristics in deuterium-tritium thermonuclear plasmas
Authors: Matsuura H. , Nakao Y.
Published: June 2006

An effect of nuclear elastic scattering (NES) on the energy transfer to plasma ions and electrons during (a) neutral beam injection (NBI) and (b) α-particle heating operations is examined on the basis of the Boltzmann-Fokker-Planck (BFP) equation for a beam ion and an α-particle in deuterium-tritium thermonuclear plasmas. The BFP calculations show that the enhancement in the fraction of the NBI heating power deposited to ions due to NES becomes appreciable when the beam energy is larger than 1MeV. How the NES effect is influenced by the plasma condition is discussed.
Converse magnetoelectric effect in laminated composites of PMN–PT single crystal and Terfenol-D alloy
Authors: Jia Yanmin , Or Siu Wing , Chan Helen Lai Wa , Zhao Xiangyong , Luo Haosu
Published: June 2006

We have found experimentally and theoretically that laminated composites comprising one layer of length-magnetized Tb0.3Dy0.7Fe1.92 (Terfenol-D) magnetostrictive alloy sandwiched between two layers of thickness-polarized, electro-parallel-connected 0.7Pb(Mg1∕3Nb2∕3)O3–0.3PbTiO3 (PMN–PT) piezoelectric single crystal have a large converse magnetoelectric effect characterized by a large magnetic induction in response to an applied ac voltage. The reported converse magnetoelectric effect originates from the product of the converse piezoelectric effect in the PMN–PT layers and the converse magnetostrictive effect in the Terfenol-D layer. Large converse magnetoelectric coefficient in excess of 105mG∕V is obtained in the composites at a low magnetic bias field of 170Oe. The measured magnetic induction has an excellent linear relationship to the applied ac voltage with amplitude varying from 50to160V. These made the composites to be a promising material for direct realization of core-free magnetic flux control devices.
Photorefractive effects in magnesium doped lithium niobate whispering gallery mode resonators
Authors: Savchenkov Anatoliy A. , Matsko Andrey B. , Strekalov Dmitry , Ilchenko Vladimir S. , Maleki Lute
Published: June 2006

We report on the study of near-infrared photorefractivity in highly Mg doped as-grown congruent LiNbO3 forming a whispering gallery mode resonator. The resonator is pumped with 780nm light. We have observed a change of the ordinary index of refraction of the material exceeding 8×10−5. We show that the basic features of the photorefraction in this type of crystal is different from the photorefraction in nominally pure as-grown congruent LiNbO3 and explain the origin of this difference.
Mg–Ti–H thin films for smart solar collectors
Authors: Borsa D. M. , Baldi A. , Pasturel M. , Schreuders H. , Dam B. , Griessen R. , Vermeulen P. , Notten P. H. L.
Published: June 2006

Mg–Ti–H thin films are found to have very attractive optical properties: they absorb 87% of the solar radiation in the hydrogenated state and only 32% in the metallic state. Furthermore, in the absorbing state Mg–Ti–H has a low emissivity; at 400K only 10% of blackbody radiation is emitted. The transition between both optical states is fast, robust, and reversible. The sum of these properties highlights the applicability of such materials as switchable smart coatings in solar collectors.
A neoclassical calculation of toroidal rotation profiles and comparison with DIII-D measurements
Authors: Stacey W. M. , Johnson R. W. , Mandrekas J.
Published: June 2006

Momentum and particle balance and neoclassical viscosity were applied to calculate the radial profile of toroidal rotation velocity in several DIII-D [J. Luxon, Nucl. Fusion 42, 614 (2002)] discharges in a variety of energy confinement regimes (low-mode, low-mode with internal transport barrier, high-mode, and high-mode with quiescentd double barrier). Calculated toroidal rotation velocities generally were found to (over) predict measured values to well within a factor of 2.
Electrical characterization of defects introduced during electron beam deposition of Pd Schottky contacts on n-type Ge
Authors: Auret F. D. , Meyer W. E. , Coelho S. , Hayes M.
Published: June 2006

We have investigated by deep level transient spectroscopy the hole and electron trap defects introduced in n-type Ge during electron beam deposition (EBD) of Pd Schottky contacts. We have also compared the properties of these defects with those introduced in the same material during high-energy electron irradiation. Our results show that EBD introduces several electron and hole traps at and near the surface of Ge. The main defect introduced during EBD has electronic properties similar to those of the V–Sb complex, or E center, introduced during high-energy particle irradiation of Ge. This defect has two levels E0.38 and H0.30 that correspond to its (−−,−) and (−,0) charge states.
Sol-gel synthesis and photoluminescence of p-type semiconductor Cr2O3 nanowires
Authors: Cao Huaqiang , Qiu Xianqing , Liang Yu , Zhao Meijuan , Zhu Qiming
Published: June 2006

Rhombohedral structure p-type semiconductor Cr2O3 nanowires were generated by sol-gel template technology with the diameters in the range of 100–300nm and the lengths ca. 10μm. A sharp ultraviolet photoluminescence band (full width at half maximum=13.8nm) at the wavelength of 385nm (3.22eV in photon energy) was observed, which was attributed to the transition involving 3d3 electron of the Cr3+ ions.
Role of edge dislocations in enhancing the yellow luminescence of n-type GaN
Authors: Zhao D. G. , Jiang D. S. , Yang Hui , Zhu J. J. , Liu Z. S. , Zhang S. M. , Liang J. W. , Li X. , Li X. Y. , Gong H. M.
Published: June 2006

We investigate the origin of yellow luminescence in n-type GaN. It is found that the relative intensity of yellow luminescence increases as the full width at half maximum of the x-ray diffraction rocking curve at the (102) plane increases. This indicates that the yellow luminescence is related to the edge dislocation density. In addition, the relative intensity of yellow luminescence is confirmed to increase with increasing Si doping for the high quality GaN we have obtained. We propose that the yellow luminescence is effectively enhanced by the transition from donor impurities such as Si to acceptors around the edge dislocations in n-type GaN.
Growth trends of Queensland east coast Spanish mackerel (Scomberomorus commerson) from otolith back-calculations
Authors: Ballagh Aaron C. , Begg Gavin A. , Mapleston Amos , Tobin Andrew
Published: June 2006

The growth of narrow-barred Spanish mackerel (Scomberomorus commerson) was examined over a broad spatial scale encompassing the east coast of Queensland, Australia. Our aim was to use back-calculation to identify potential biases in growth estimation, and to provide a more recent estimate of growth for Spanish mackerel on the east coast of Queensland. Growth trends were determined using the body proportional hypothesis (BPH) back-calculation model and compared between back-calculated and observed length-at-age data. The back-calculated von Bertalanffy growth function parameters estimated for males and females, respectively, were L∞ = 1047 mm, K = 0.75, t0 = –0.18 and L∞ = 1248 mm, K = 0.51 and t0 = –0.39. Significant differences in growth of Spanish mackerel sampled among different regions along the east coast were observed. A comparison of back-calculated and observed length-at-age data revealed significant biases in the observed length-at-age data for younger aged fish. Our findings contrast with previous estimates of growth for Spanish mackerel from the east coast of Queensland and highlight the use of back-calculation for the first few annuli as a means of avoiding biases in growth estimation arising from gear selectivity associated with fishery-dependent samples of fast-growing fish.
Validating ecological risk assessments for fisheries: assessing the impacts of turtle excluder devices on elasmobranch bycatch populations in an Australian trawl fishery
Authors: Griffiths Shane P. , Brewer David T. , Heales Don S. , Milton David A. , Stobutzki Ilona C.
Published: June 2006

Demonstrating ecological sustainability is a challenge for fisheries worldwide, and few methods can quantify fishing impacts on diverse, low value or rare species. The current study employed a widely used ecological risk assessment method and incorporated new data to assess the change in sustainability of species following the introduction of Turtle Excluder Devices (TEDs) in Australia’s Northern Prawn Fishery (NPF). Population recovery ranks changed for 19 of the 56 elasmobranch species after the introduction of TEDs, with nine species showing an increase in sustainability. Unexpectedly, ten species showed a decrease in sustainability. This was due to TEDs successfully excluding large animals from the catch, resulting in a lower mean length at capture, which reduced the recovery ranks for two criteria relying on length data. This falsely indicates that TEDs increase the impact on pre-breeding animals, thus reducing the recovery potential of these species. The results demonstrate that existing attribute-based risk assessment methods may be inadequate for reflecting even the most obvious changes in fishing impacts on bycatch species. Industry and management can benefit greatly from an approach that more accurately estimates absolute risk. The development and requirements of a new quantitative risk assessment method to be developed for the NPF, and applicable to fisheries worldwide, are discussed.
Detection and enumeration of microbial cells within highly porous calcareous reef sands
Authors: Wild Christian , Laforsch Christian , Huettel Markus
Published: June 2006

In order to assess and to compare the abundances of prokaryotes in coral sands from three different areas in the Indo-Pacific, a technique was developed and evaluated for enumeration of prokaryotes living on and within calcareous grains. Propidium iodide labelling of prokaryotes and consecutive confocal laser scanning microscopy showed microbial colonisation within pores and small fissures of the coral sands. This embedded microbial colonisation required at least four extractions with weak acetic acid to dissolve the grain surface layer in order to detach 97% of the prokaryotic cells. Microbial enumeration based on this technique revealed that the abundance of prokaryotes in the carbonate sands were not significantly different among the three sites, but were about one order of magnitude higher than reported for silicate sands of a similar grain size spectrum. A possible reason for this high abundance of prokaryotes is the complex surface structure of the biogenic calcareous grains, their correspondingly highly porous matrix and the associated ability of prokaryotes to penetrate into carbonate grains. Our results highlight the role of calcareous reef sands as a substratum with a large specific surface area for prokaryotic colonisation and emphasise the contribution of calcium carbonate reef sands for element cycles in subtropical and tropical ecosystems.
A mechanism of translational repression by competition of Paip2 with eIF4G for poly(A) binding protein (PABP) binding
Authors: Karim Muhammad M. , Svitkin Yuri V. , Kahvejian Avak , De Crescenzo Gregory , Costa-Mattioli Mauro , Sonenberg Nahum
Published: June 2006

The eukaryotic mRNA 3′ poly(A) tail and the 5′ cap cooperate to synergistically enhance translation. This interaction is mediated by the cap-binding protein eIF4E, the poly(A) binding protein (PABP), and eIF4G, a scaffolding protein that bridges between eIF4E and PABP to bring about the circularization of the mRNA. The translational repressor, Paip2 (PABP-interacting protein 2), inhibits translation by promoting the dissociation of PABP from poly(A). Here we report on the existence of an alternative mechanism by which Paip2 inhibits translation by competing with eIF4G for binding to PABP. We demonstrate that Paip2 can abrogate the translational activity of PABP, which is tethered to the 3′ end of the mRNA. Thus, Paip2 can inhibit translation by a previously unrecognized mechanism, which is independent of its ability to disrupt PABP–poly(A) interaction.
Marine turtles in Malaysia: On the verge of extinction?
Authors: Chan Eng-Heng
Published: June 2006

Four species of marine turtles (leatherback, green turtle, hawksbill and olive ridley) are found in Malaysia. Current statistics indicate that the leatherback and olive ridley turtles are on the verge of extinction in Malaysia; while other species, excluding the green turtles of the Sabah Turtle Islands, are in steady decline. Consumptive utilization in the form of egg exploitation until recently, took place mainly in Terengganu. Turtles are also being used to promote tourism in Terengganu and Sabah. Population decline is attributed to a long history of egg exploitation, commercial hunting and harvesting of marine turtles in neighbouring countries, fishing mortality, loss of nesting habitats, marine pollution, negative impacts of tourism and the lack of a national strategy on marine turtle conservation. Marine turtle conservation efforts in Malaysia are not lacking, but need to be upgraded and coordinated. Legislation among the various states of Malaysia should be harmonized to ensure greater protection for these endangered animals. Existing egg incubation programmes should be expanded to secure a higher level of egg protection. More sanctuaries should be established in key nesting sites and Malaysia should join her neighbours in ratifying current regional instruments aimed at marine turtle conservation.
Diversity of Malaysian aquatic ecosystems and resources
Authors: Yusoff F. M. , Shariff M. , Gopinath N.
Published: June 2006

Malaysia has rich aquatic ecosystems that supply vital resources such as water, food, medicine, commercial aquatic resources, energy and transport for economic and social development of its people. In addition, they also provide other services such as flood control, erosion prevention and shoreline protection, recreational fisheries and resources for tourism industry. However, the ubiquitous and abundant supplies of these resources in the past have resulted in minimal concern about their conservation and sustainable exploitation. In fact, these resources are continuously threatened by human activities such as overexploitation of living resources, massive land reclamation and development, discharge of harmful industrial and domestic wastes, and large energy development projects. Threats to the sustainability of these resources in the form of land-based and sea-based pollution are becoming serious, and have affected the health and wealth of the people. The manifestations of the disregard to the aquatic environment are already obvious, as evidenced by the frequent reports on water shortage, polluted rivers and seas, decrease in fisheries commodities, decline of aesthetic values in water-based recreational areas and decrease in biodiversity. Various laws and regulations have not been able to deter some of these ecosystems from being continually exploited on unsustainable basis. Concerted efforts from all stakeholders are critical to protect these valuable ecosystems such that their resources would continue to provide life necessities for generations to come. Preventive measures, such as the implementation of holistic environmental management, increased public education and the early use of efficient and cost-effective pollution control measures through research efforts and the acquisition of clean technology, should be implemented to achieve desired level of pollution abatement. These efforts by the Government should be complemented and supplemented by investments from the private sector to achieve a clean, healthy and productive aquatic environment for both present and future generations.
Spectra of quantized hyperalgebras
Authors: Chin William , Krop Leonid
Published: June 2006

We describe the prime and primitive spectra for quantized enveloping algebras at roots of 1 in characteristic zero in terms of the prime spectrum of the underlying enveloping algebra. Our methods come from the theory of Hopf algebra crossed products. For primitive ideals we obtain an analogue of Duflo’s Theorem, which says that every primitive ideal is the annihilator of a simple highest weight module. This depends on an extension of Lusztig’s tensor product theorem.
A preparation theorem for Weierstrass systems
Authors: Miller Daniel
Published: June 2006

It is shown that Lion and Rolin’s preparation theorem for globally subanalytic functions holds for the collection of definable functions in any expansion of the real ordered field by a Weierstrass system.
Beyond the Linear Frequentist Orthodoxy
Authors: Schrodt Philip A.
Published: June 2006

Every good book has a small bit—a sentence, paragraph, maybe a page—that the authors intended as a simple aside but which brings an epiphany to the reader. In Brady and Collier (2004), this occurs at the beginning of chapter 3: Brady's critique of the “quantitative template,” where the recovering seminarian frames our discourse on the philosophy of social inquiry in terms of pragmatic theology and homeliletics, rather than science or sociology. Hey, that is it!—while this debate is not in any sense about religion, its dynamics are best understood as though it were about religion. We have always known that, it just needed to be said.
Interactions of asparagns root tissue with soil microorganisms as a factor in early decline of asparagus
Authors: BLOK W. J. , BOLLEN G. J.
Published: June 2006

Sterilized root residues of asparagus added at a rate of up to 20gkg‐1 fresh soil did not influence severity of root and crown rot caused by Fusarium oxysporum f.sp. asparagi (Foa). Root residues accumulated in field soil during asparagus growing for 10 years did not influence disease severity either. Inoculation of this soil with laboratory‐prepared Foa after treatment at 65°C (30min), at which the indigenous pathogen was killed but toxic substances present in asparagus root residues were left undamaged, led to the same disease severity as inoculation of similarly‐treated fresh soil.

On soil extract agar, aqueous root extracts of asparagus but not those of other crops retarded growth of 31 out of 112 fungal isolates from a range of taxa. Sensitive fungi included Gliocladium spp. and Trichoderma harzianum, but not Foa.

Colonization of Foa‐infested soil by Fusarium species was greatly enhanced by addition of root material from asparagus, Brussels sprouts, and chicory, but not by that from strawberry and perennial rye grass. As the fraction of Foa amongst the Fusarium population was small, it is concluded that competitive saprophytic ability of the pathogen is far less than that of the nonpathogenic Fusarium species. Fungistasis to Foa was not or was only slightly reduced in soils amended with root residues.

In contrast to data reported in the literature, the present results do not suggest an appreciable increase of Foa root rot., or of the Foa population in soils, due to substances present in root residues.
Biological, serological and molecular characterization of a cucumber mosaic virus isolate from India
Authors: HAQ Q. M. R. , SINGH B. P. , SRIVASTAVA K. M.
Published: June 2006

A. virus causing mosaic and leaf deformation of Physalis minima has been identified as an isolate of cucumber mosaic virus (CMV) on the basis of its transmission by aphids in a non‐persistent manner, polyhedral particles of 29 nm diameter, molecular weight of coat protein subunits us 24‐5 kDa. serological relationship with a CMV isolate and a tripartite single‐stranded RNA genome with a subgenomic RNA4‐ Furthermore. cDNA representing coat protein gene was synthesized and cloned. Complete nucleotide sequences (890 nt) were obtained which showed a coat protein gene open reading frame of 657 residues. THE nucleotide sequences provided the 218 amino ACID sequences of the coat protein. Nucleotide as well as amino acid sequences revealed more than 90% identity with the CMV subgroup I strains.
A viral disease of broad bean caused by a non‐aphid‐transmissible strain of turnip mosaic virus
Authors: HU W. Q. , PU Z. Q. , XU Z. G. , FANG Z. D.
Published: June 2006

A viral disease of broad bean (Vicia faba) was observed in Jiangsu, Zhejiang and Sichuan Province, the People's Republic of China. Its typical symptom on infected leaves was a white mottle, and, rarely, red necrotic lesions on several broad bean cultivars. A non‐aphid‐transmissible strain of turnip mosaic virus (TuMV) was identified as the causal agent of the disease on the basis of biological properties, particle morphology, seed and aphid transmission and serological tests. The virus could not be transmitted by aphids in the non‐persistent manner.
Screening pearl millet cultivars by ELISA for resistance to downy mildew disease
Authors: SHISHUPALA S. , KUMAR V. U. , SHETTY H. SHEKAR , UMESH‐KUMAR S.
Published: June 2006

In an earlier study, we described identification of a protein from a virulent pathotype of Sclerospora graminicola, the binding reaction of which differentiated susceptible and resistant cultivars of pearl millet to downy mildew disease. This protein and corresponding antibody were used in an enzyme‐linked immunosorbent assay (ELISA) to screen suspension cells of pearl millet cultivars for their resistance to the downy mildew pathogen. Screening results for 31 pearl millet cultivars correlated positively with the established field screening method.
Identification of cowpea (Vigna unguiculata) cultivars and lines immune to variants of blackeye cowpea mosaic potyvirus
Authors: BASHIR M. , HAMPTON R. O.
Published: June 2006

Fifty‐one cowpea (Vigna unguiculata) cultivars and lines were tested by mechanical inoculation against seven geographically and pathogenically diverse isolates of blackeye cowpea mosaic potyvirus (BICMV), to identify genetic resources with comprehensive BICMV resistance. Five genotypes, IT 80S 2049, Big Boy, Corona, Serido, and Tennessee Cream #8 were immune from all seven isolates, and an additional three genotypes, TVu‐2657, TVu‐2740, and TVu‐3433, were immune from all isolates except PU‐7B, an aberrant B1CMV isolate. The diversity among BICMV isolates was illustrated by the range of responses to inoculation among cowpea genotypes, many of which were either immune from or tolerant of individual B1CMV isolates.
Identification of a uninucleate Rhizoctonia sp. by pathogenicity, hyphal anastomosis and RAPD analysis
Authors: LILJA A. , HIETALA A. M. , KARJALAINEN R.
Published: June 2006

Finnish and Norwegian uninucleate Rhizoctonia sp, isolates. originating from roots of nursery grown conifer seedlings suffering from root dieback, and having Ceratobasidium perfect state, were tested for pathogenicity and genetic related ness. All tested isolates of this pathogen considerably reduced the root system development of Scots pine and Norway spruce seedlings resulting in death or stunted growth. The uninucleate isolates anastomosed readily with each other producing a killing reaction. In a RAPD‐PCR analysis, the uninucleate isolates had different banding patterns from our reference isolates, two Finnish binucleate isolates (AG‐I and R. sp.) and standard tester isolates of genus Ceratobasidium representing anastomosis groups AG‐A, AG‐C, AG‐E, AG‐G and AG‐I. UPGMA analysis clustered the uninucleate isolates together at a greater similarity than 75% while the binucleate isolates formed distinct clusters and were 10‐25% similar to the uninucleate Rhizoctonia sp. Hyphal anastomosis and DNA data suggest that the uninucleate Rhizocionia sp. is an homogeneous group and distinct from the tested binucleate Rhizoctonia isolates.
SEDIMENTATION IN SAN DIEGO TROUGH AND CONTRIBUTING SUBMARINE CANYONS
Authors: SHEPARD FRANCIS P. , EINSELE GERHARD
Published: June 2006

There are a series of basins off southern California, all presumably due to faulting of the broad continental borderland. Of these, San Diego Trough is the only one where sedimentation has gone on sufficiently to fill the basin depressions so that there is a continuous slope southward to where the trough connects with the deeper San Clemente Basin. This deposition has apparently come to a very great extent from turbidity currents moving down submarine canyons developing channeled fans at the canyon bases. All along the canyons and channels as well as across the fans and in San Diego Trough there are sequences of turbidite sands alternating with muddy sediments that represent the normal deep water sedimentation. Comparison of the coarse fraction from the sands and from the interbedded muds shows that the former are predominantly terrigenous in character whereas a large proportion of the latter are biogenous. Mica is quite low in the coarser sand layers but is abundant in the coarse fraction of the muds. Diatoms and radiolarians are largely confined to the mud layers where they may constitute a large percentage of the sand fraction.

Study of the heavy and light minerals shows that the sediments of San Diego Trough are derived largely from the nearby land masses rather than having a considerable admixture from the north as would be the case if sediments were being brought down by turbidity currents coming into the trough from the north. The alterites are appa‐rently lower in San Diego Trough than in the near shore source area which suggests that a supply of sediments may be picked up from the canyon or channel walls along the way to the trough. Also the finding of the only coarse sands in the middle reaches of the channels suggests local sources as does the general make up of these coarse sands. Despite these locally derived coarse sands the prevalence of very fine sand and the “mud” layers between sand layers suggest that the turbidity currents supplying sediments to San Diego Trough have low velocities or at any rate little erosive capacity.
PRELIMINARY NOTE ON THE GRANULOMETRIC ANALYSIS OF SEDIMENTARY ROCKS
Authors: VAN DER PLAS L.
Published: June 2006

The observation that the results of line and point counting analyses of the particle size distribution of the same sand are different leads to the conclusion that these results are biased by the sampling technique1. The influence of the currently used sampling techniques on the numerical results of a particle size analysis is discussed. Evidence is presented to show that the use of line and point counting methods in granulometric analysis leads to results in which the influence of the sampling method is so strong that the practical value of these techniques is doubtful. It is therefore considered advisable to discontinue line and point counting techniques in granulometric analysis in favour of ribbon sampling methods.
THE CLASSIFICATION OF CROSS‐STRATIFIED UNITS. WITH NOTES ON THEIR ORIGIN
Authors: ALLEN J. R. L.
Published: June 2006

A descriptive classification of cross‐stratified units is proposed based on six objective criteria, and diagnoses are given for fifteen distinct kinds of cross‐stratified unit recognised with their aid. The origin of each kind is discussed in the light of existing observational, experimental, and theoretical studies. A three‐fold genetic classification of cross‐stratified units is tentatively outlined in which apparent origin and physical properties are closely correlated.
HYDRAULIC STUDIES ON THE ORIGIN OF BEDDING
Authors: JOPLING ALAN V.
Published: June 2006

A series of quasi‐quantitative experiments on delta building were carried out in a laboratory flume for the purpose of studying the mechanics of deposition of topsets, foresets, and bottomsets. The genesis of these sets can be rationally explained through the discipline of sediment transport mechanics by taking cognizance of (a) the hydraulic phenomena of gradually varied and rapidly varied flow, (6) the concept of aggradation to a profile of equilibrium. The geometry of a delta front is controlled by the dynamics of the environment of deposition, and the frontal profile can be inter‐ preted as a function of the micro‐mechanics of particle movement in the transition zone where the stream enters the basin of deposition.
STRUCTURES IN SHALLOW‐WATER PRECAMBRIAN SEDIMENTS FROM NORTHWEST SCOTLAND
Authors: SUTTON JOHN , WATSON JANET
Published: June 2006

The paper deals with sedimentary structures in shallow‐water Precambrian deposits of Lower Torridonian age in the island of Skye in northwestern Scotland. The structures described include irregular lamination, ripple bedding, festoon bedding and structures produced by local erosion and reworking. Evidence of penecontemporaneous disturbance thought to be due to the movements of quicksands is briefly referred to. Variations in lithology and structure within the succession are attributed to local differences in conditions within a possible environment of sedimentation in an intertidal zone with off‐shore sandbanks.
FACTORS INFLUENCING THE PORE VOLUME OF FINE‐GRAINED SEDIMENTS UNDER LOW‐TO‐MODERATE OVERBURDEN LOADS1
Authors: MEADE ROBERT H.
Published: June 2006

An anomalous increase of pore volume with increasing depth in the range 0—1,900 ft. occurs in fine‐grained sediments along the east side of the San Joaquin Valley of Cali‐ fornia. Several possible causes for the anomaly were inferred from a literature search and from study of the core samples. Statistical analyses of the core sample data suggest the principle causes to be variations in particle size, the diatom‐skeleton content, and the type of exchangeable cation adsorbed by the clay‐mineral constituents of the sediments.
AUTHIGENIC SILICATE MINERALS IN SEARLES LAKE, CALIFORNIA
Authors: HAY R. L. , MOIOLA R. J.
Published: June 2006

Monoclinic K‐feldspar, analcime, searlesite and phillipsite of diagenetic origin are present in samples of clay and tuff from U. S. Geological Survey cores of Pleistocene and Recent sediments of Searles Lake, California. Authigenic K‐feldspar was identified in 37 of the 72 samples studied; analcime was identified in 21, searlesite in 8, and phillipsite in 3. Most of the K‐feldspar, analcime, and searlesite occur in non‐tuffaceous claystones, which form about 46% of the 875‐ft. thickness of sediments that was cored. Phillipsite was found only in three rhyolitic tuff laminae within the upper 110 ft. of beds. Most of the K‐feldspar and analcime crystals are less than 2 μ in diameter, and maximum diameters are 0.10 mm for K‐feldspar and 0.02 mm for analcime. Phillipsite occurs as lath‐shaped crystals 0.01–0.02 mm long, and searlesite principally forms spherulites 0.02–0.2 mm in diameter.

Microcline, orthoclase, albite, andesine, and quartz predominate in the sand and silt fraction of the clays; illite, montmorillonite, chlorite, and kaolinite predominate in the detrital clay fraction. Grains of quartz and andesine are extensively etched at various levels below a depth of 220 ft., and only skeletal crystals of andesine remain in some clays. Volcanic glass has been completely dissolved or replaced by authigenic silicate minerals in the few tuffs. Distribution of clay minerals in the core suggests that montmorillonite and chlorite have been destroyed in many of the clays.

Alkaline brine saturates the surface and subsurface sediments, and the high activity ratio of alkali ions to hydrogen ions in this brine probably accounts for the widespread formation of K‐feldspar, zeolites, and searlesite. Na, K, and B for the authigenic silicates were probably supplied by the brine and by saline minerals in contact with the brine. Montmorillonite may have provided additional K. Solution of glass provided the Si and Al required to form authigenic silicate minerals in the tuffs, and solution of quartz, plagioclase, and montmorillonite most likely supplied the Si and Al for authigenic silicates in the clays.
CYCLIC SEDIMENTATION IN THE LOWER WESTPHALIAN OF NO DEVON, ENGLAND
Authors: DE RAAF J. F. M. , READING H. G. , WALKER R. G.
Published: June 2006

Eleven facies of the (Lower Westphalian) Abbotsham Formation and upper portion of the Northam Formation of north Devon are described: black mudstone, silty mudstone, “turbidite”, silty streak, sandy streak, three kinds of oscillatory beds, cross‐stratified sandstones and mudstones, fining‐upwards units and major sandstones. Their relationships to each other are determined and they are shown to recur in a cyclic pattern.

Six cycles are distinguished in the 1,200 ft. of the Abbotsham Formation. Each passes upwards gradually from black mudstone into coarser beds, the top of which is sharply separated from the black mudstone of the succeeding cycle.

We suggest that the environment of deposition of these cycles ranges from a moderately deep basin, in which mudstones and occasional turbidites were deposited, through the sediments of an advancing coastline, fronted by deltas, to coastal plains in which fluviatile sediments were laid down.
ENVIRONMENT RECONSTRUCTION FOR A PART OF THE GLEN ROSE LIMESTONE, CENTRAL TEXAS
Authors: BEHRENS E. WILLIAM
Published: June 2006

An approximately 50 ft. stratigraphic section of the Lower Cretaceous Glen Rose Limestone was sampled at 24 separate localities in central Texas from the standpoint of reconstructing the depositional environment. Among these samples 199 representative specimens were selected and subjected to point‐count analyses, X‐ray analyses, and insoluble residue determinations. Statistical analysis of the accumulated data with an IBM 7090 computer yielded the following facies: Corbula facies—characterized by a relative abundance of thick‐shelled ostracods, thin‐walled miliolid foraminifers, and the small pelecypod Corbula martinae; steinkern facies—characterized by large mollusc steinkerns, cellular mollusc shells and the foraminifer Orbitolina; mudstone facies—typified by less than 10% sand‐sized grains; and mixed particle facies—characterized by worn skeletal and nonskeletal carbonate grains. The mud‐stone facies subsequently was divided into two subfacies: (1) lime mudstones—characterized by delicate skeletal constituents and lime mud, and (2) marly mud‐stones—consisting of a mixture of lime mud and terrigenous clay‐sized material. Similarly the mixed particle facies was divided into four subfacies: skeletal calcarenites—characterized by sand‐sized skeletal debris; skeletal wackestones—consisting of sand‐sized skeletal particles floating in a mud matrix; nonskeletal calcarenites—characterized by nonskeletal carbonate grains; and nonskeletal wackestones—consisting of nonskeletal carbonate grains floating in a mud matrix. In addition limey sandstone, dolomite, and stromatolite facies were distinguished on the basis of relatively obvious textures and compositions.

The attributes of these facies as evidenced by the 199 statistically analyzed specimens were then used to assign each of the additional samples (350) to a particular facies and to identify the distribution of these facies in the field. A reconstruction of the depositional environment was made for each facies, and the following depositional history was interpreted from the resulting facies pattern.

The lowermost beds of the unit, consisting largely of stromatolites and nonskeletal calcarenites, are interpreted as representing deposition in very shallow, probably intertidal, waters, Following the deposition of these beds, the depth of water increased
BORON IN HOLOCENE ILLITES OF THE DOVEY ESTUARY, WALES, AND ITS RELATIONSHIP TO PALAEOSALINITY IN CYCLOTHEMS1
Authors: ADAMS T. D. , HAYNES J. R. , WALKER C. T.
Published: June 2006

Results from modern and ancient sediments suggest that a boron‐illite equilibrium, reflecting salinity, is established at the time of deposition. This condition is not appreciably changed by subsequent processes of diagenesis and lithification. Equivalent boron in thirteen samples, from two augerholes through Dovey Estuary sediments, ranges between 260 p.p.m. and 370 p.p.m. and averages 336 ± 29 p.p.m. (95% confidence limits).

Salinity conditions in the present estuary vary greatly. A very significant direct correlation exists between equivalent boron and inferred depositional salinity of Dovey Estuary sediments.
THE USE OF ANISOTROPY OF MAGNETIC SUSCEPTIBILITY IN THE ESTIMATION OF SEDIMENTARY FABRIC1
Authors: REES A. I.
Published: June 2006

The feasibility is discussed of using anisotropy of magnetic susceptibility to find preferred directions of grain orientation and current directions in sediments, and it is concluded that it should be possible to find these directions in silts and sands containing between 0.01 and 1% of magnetite.

Some examples are given of the use of the method under controlled conditions, and it is shown to give the same result as optical grain orientation determination in one example and to predict the same current direction as macroscopic indications in two others. Some of the limitations of the method are suggested by examples in which the results would have been misleading if accepted unconditionally.
GRADATIONAL SEDIMENTARY PRODUCTS OF CALCAREOUS ALGAE
Authors: WOLF KARL H.
Published: June 2006

Penecontemporaneous calcareous algal products are very complex in both texture and mode of origin. For example, all gradations exist between stromatolites and pseudo‐stromata, different types of oncolites are transitional and are often difficult to distinguish from other allochthonous algal material, algal pellets form the final product of abrasion and they too are very similar despite variations independent of their original source; and some Algae may break down into “algal dust” or carbonate needles.

Algal limestones of different ages and environments may supply detritus that is indistinguishable from one another. Therefore, in petrographic investigations of carbonate sediments the descriptive term “limeclast” is less ambiguous than the genetic terms “intraclast” and “calclithite”. If a combination of field‐work and thin‐section studies permits precise genetic and environmental interpretations, the limeclasts can be genetically described as “intraclasts” and “extraclasts”. If the extraclasts form the predominant components, the sediment is a “calclithite” and is a type of terrigenous rock (FOLK, 1959).

In general, four possible relations exist between limestone frameworks and micrite matrices. Both allochthonous fragment accumulations and autochthonous growths may have either detrital matrices or matrices that formed in situ. The autochthonous algal micrite matrices give no indication of a degree of turbulence and winnowing in contrast to allochthonous matrices.

Apparently minute differences, which are, however, significant in the genesis of limestone components may become more important with an increase in isotope, trace element and diagenetic investigations where the identity of the carbonate material is of special importance.
FALLING DROP USED FOR GRAIN‐SIZE ANALYSIS OF FINE‐GRAINED MATERIALS
Authors: MOUM JOHAN
Published: June 2006

To facilitate simultaneous performances of numerous grain‐size analyses covering the silt and clay fractions, a method has been worked out and the necessary equipment constructed for utilizing a falling drop for determining densities of particle suspensions. A drop is taken out by means of a micro‐syringe at the desired depth in a sedimentation vessel, and ejected into a column of an organic liquid with a slightly lower density. The drop then falls with a constant speed and the time measured with a stopwatch over a certain distance is a measure of the density of the drop, and hence also of the particle concentration in the sedimentation vessel where the drop is taken. In this way it is easily possible to work through twenty samples in a normal working day, including removal of organic matter, dispersion, washing (to remove effects of soluble salts) and evaluating the final results.
THE DEVELOPMENT OF OVERGROWTHS FROM ECHINODERM FRAGMENTS
Authors: EVAMY B. D. , SHEARMAN D. J.
Published: June 2006

An overgrowth from an echinoderm fragment is a single crystal of calcite in lattice continuity with the calcite crystal of the host. The development history of echinoderm overgrowths during cementation has been elucidated by the identification of iron‐bearing and iron‐free calcites within the overgrowths by employing staining techniques.

The iron‐bearing parts of the overgrowths described do not stain uniformly for iron. Instead they exhibit a succession of light and dark stained sub‐zones, which represent the shapes of the overgrowths during their development.

The pattern of zoning around basal sections of crinoid ossicles is comparatively simple. The innermost zones follow the outlines of the ossicles. Later zones adopt first quasi‐hexagonal outlines with curved sides, and then true hexagonal zones of prismatic habit. Such basal sections of ossicles give well‐centred conoscope images and are therefore, oriented perpendicular to the c‐axis directions of their calcites.

Vertical sections through overgrowths show a more complex zoning: above and below the articulating surfaces of ossicles the zones are wide, and have a marked zig‐zag outline, with the axes of the spires parallel to the vertical axes of the ossicles and parallel to the c‐axes of the crystals. Along the sides of the ossicles the zones are narrow and straight. The multiple terminations in the c‐axis direction reduce in number away from the surface of the ossicle and, if the original pore‐spaces are sufficiently large, ultimately yield a single scalenohedron‐type termination. The multiple terminations have their origins on the articulating surfaces of the ossicles. In life these surfaces were perforated by the entrances to the numerous minor canals which ramify the ossicles. The multiplicity of terminations resulted from more rapid crystal growth from the surface of the ossicle between canals (c‐axis direction) than from the surfaces of the canals themselves (direction perpendicular to the c‐axis).
EVOLUTION OF ZIRCONS IN SEDIMENTARY AND METAMORPHIC ROCKS
Authors: SAXENA S. K.
Published: June 2006

Zircons have been studied in the sedimentary rocks of the Sparagmite Group (Eocambrian) and their metamorphic associates from the Trondheim area and the adjacent regions in Norway and Sweden. The majority of zircon population (type B) has been formed in the sediments by authigenesis. Another authigenic associate is rutile. The authigenic zircons have irregular, round and ellipsoidal habits. In metamorphic rocks the same grains show a greater tendency of euhedrism, forming drum‐like crystals with acute (331) pyramids and short prisms. Authigenic zircons are usually clear and transparent but some grains may show cloudy appearance. A few other grains (type A) with different habit and many inclusions appear to be of detritai nature.

Dissolution of a metamictized zircon population in the source rock is possible in many ways. An important possibility is the dissolution of zircons in alkaline solution. Carbonated lime‐rich waters or other acidic solutions could be equally effective. Zirconates, so formed, are transported to the basin of deposition as colloidal particles or as ionic complexes. The authigenic process is visualized as a deposition of the zirconates by adsorption or by precipitation as zirconium hydroxide, possibly due to change in the Eh and pH in the environment. The hydrated oxide subsequently reacts with silica to form metastable hydrozircon. In course of time hydrozircon dehydrates and becomes a normal zircon.

Numerous growths have been noted and are classified genetically into (l) late authigenic growths, and (2) growths syngenetic with metamorphism. The shape of the host grain usually controls the final shape of the overgrown grain.

There is some effect of metamorphism on the morphology of the authigenic zircons. In view of the characters of the newly generated zircons, the use of shape, size, zoning and such other parameters of zircons in petrogenetic problems, has to be retested to ensure its reliability.

Rather than being a mineral of igneous derivation only, zircon is from three parentages: igneous, authigenic and metamorphic. It is argued that the persistence of the authigenic zircons should be greatest because of very low concentration of radioactive elements.
ON BED FORMS AND PALAEOCURRENTS
Authors: ALLEN J. R. L.
Published: June 2006

Bed forms arise by interaction between a fluid flow and the sediment transported over or close to the bed. The geometry of bed forms is two‐dimensional or three‐dimensional. Two‐dimensional bed forms generate two‐dimensional internal sedimentary structures and are adjusted to two‐dimensional flow‐vector fields. Three‐dimensional bed forms generate three‐dimensional internal sedimentary structures and are adjusted to three‐dimensional flow‐vector fields. Many shallow‐water flow systems observable today are each characterised by flow‐vector fields of unequal rank, and hence are hierarchically structured. Hierarchies of bed forms and internal structures which parallel the hierarchies of flow‐vector fields can also be established in the case of these flow systems. A single type of bed form or internal structure from an hierarchically structured flow system cannot specify that system fully with regard to either its directional or flow‐dynamic characteristics. An approach to palaeocurrent analysis that is more flexible and comprehensive than previously attempted may therefore be desirable.
CORRELATION OF SOME ATLANTIC TURBIDITES
Authors: BELDERSON R. H. , LAUGHTO A. S.
Published: June 2006

A study of six gravity cores from an abyssal plain at the western side of the Madeira‐Cape Verde Basin shows that individual turbidites can extend over a distance of at least 35 miles (65 km) in this area of final turbidity current deposition. Cores from the continental rise include relatively thinner turbidites; evidence from one of these indicates some local erosion of the sea floor: this apparently did not exceed 15 cm (as represented in the core).
APPLICATION OF THEORY TO AN ATLANTIC TURBIDITY‐CURRENT PATH
Authors: JOHNSON M. A.
Published: June 2006

Some results of turbidity‐current theory are applied to analyses of turbidite layers in cores from the route of a large turbidity current of sheet‐flow type. Novel features are that current velocity is estimated from the sediment sizes deposited, and the lateral spreading of the current is considered. An approximate quantitative picture of the current is obtained. It is compared with the turbidity current which caused the Grand Banks cable breaks.