bluuebunny/crossref_metadata_2025 huggingface dataset:
Rare earth element characteristics and K–Ar ages of the Band Ziarat ophiolite complex, southeastern Iran
Authors: Hassanipak A. A. , Ghazi A. Mohamad , Wampler J. M.
Published: October 2017

The Band Ziarat complex of southeastern Iran is located on the western boundary of the Jaz Murian depression and is bounded by two major fault systems. The principal rock units of this complex are a gabbro sequence that includes low-and high-level cumulate gabbros, a late intrusive sequence that consists of diorite and plagiogranite, and a volcanic sequence that includes diabase dikes and a lesser amount of basaltic lava. Mantle rocks are virtually absent because of the presence of the two bounding fault systems, but we consider the complex to be an ophiolite in nature. Rare earth element (REE) whole-rock data clearly differentiate the classic ophiolitic lithologies for the crustal rocks in this complex. Based on the REE data, there are two distinct types of basalt present at Band Ziarat: (i) those that formed from an initial basaltic melt with a light rare earth element (LREE) enriched signature (similar to intraplate basalts), and (ii) those that have LREE-depleted patterns (similar to normal mid-ocean-ridge basalts). The data also suggest (i) that the gabbros are accumulates and were derived from a source slightly enriched in LREE, with fractionation controlled by removal of clinopyroxene or hornblende and plagioclase, and (ii) that the late intrusive rocks as well as a majority of the diabase dikes are cogenetic and were derived from the same LREE-enriched source. K–Ar ages ranging from 134 ± 4 to 146 ± 5 Ma for low-level gabbros and from 121 ± 4 to 130 ± 4 Ma for high-level gabbros were measured on five hornblende and two whole-rock samples, which suggests that these rocks may have formed early in the Cretaceous period.
Metamorphism in the Clachnacudainn terrane and implications for tectonic setting in the southern Omineca Belt, Canadian Cordillera
Authors: Crowley J. L. , Ghent E. D. , Brown R. L.
Published: October 2017

New and previously published metamorphic data suggest that the Clachnacudainn terrane of the southern Omineca Belt has tectonic affinities with the overlying Selkirk allochthon, rather than the underlying Shuswap metamorphic complex. This interpretation is based on relationships between metamorphic minerals and deformation phases, plutons, and the upper boundary of the terrane, the Standfast Creek fault. Regional kyanite and staurolite zones in the structurally lowest part of the terrane are overlain by a garnet zone that is continuous upward across the Standfast Creek fault into the Selkirk allochthon. This metamorphism is inferred to be Jurassic age based mainly on the continuity of these zones with those of known age in the allochthon. Textural relationships show that metamorphism occurred at different times relative to deformation across the terrane. Thermobarometry and a petrogenetic grid indicate that the terrane attained lower to middle amphibolitc facies conditions. Sillimanite and andalusite zones in the contact aureoles of posttectonic mid-Cretaceous plutons overprint the regional metamorphic zones and the Standfast Creek fault. Comparison of estimated pressures shows that approximately 5–10 km of exhumation occurred between regional and contact metamorphism. These metamorphic data are interpreted to indicate that the Standfast Creek fault had minor displacement after regional metamorphism and negligible displacement after contact metamorphism. Therefore, the fault cannot be an Eocene ductile to ductile–brittle shear zone that appressed or omitted metamorphic isograds and rapidly exhumed the Clachnacudainn terrane in its footwall, as was previously proposed.
Middle Ordovician (Whiterockian) trilobiteBathyurus angeliniBillings 1859 from the Carillon Formation (uppermost Beekmantown Group) at Kahnawake, Quebec, and correlative trilobites from eastern Canada
Authors: Hofmann H J , Bolton T E
Published: October 2017

Shaly carbonate beds at the top of the Beekmantown Group in the Montreal area contain a shallow-water, nearshore fauna of the trilobite Bathyurus angelini Billings, the ostracod Isochilina sp., and poorly preserved conodonts of probable Whiterockian age. The assemblage is compared with faunas in peritidal carbonates of the upper Aguathuna and lower Table Point formations of western Newfoundland containing the trilobite Bathyurus perplexus Billings, ostracods, brachiopods, and a well-developed conodont fauna of early Whiterockian (late Arenig to early Llanvirn) age. Additionally, key Whiterockian brachiopods from the Romaine Formation of the Mingan Islands are here illustrated for the first time.
Prídolí graptolites from the Iberian Peninsula: a review of previous data and new records
Authors: Piçarra J M , Gutiérrez-Marco J C , Lenz A C , Robardet M
Published: October 2017

Prídolí graptolites are relatively rare in Iberia and, in fact, in much of southwestern Europe, because Prídolí to Early Devonian rocks are largely represented by shallow-water sandstones or siltstone-sandstone alternations. The first unambiguous find of Prídolí graptolites was the 1979 recovery of Colonograptus? transgrediens from limestone nodules occurring within the lower part of the "Upper Graptolite Shales'' in the Ossa Morena Zone of the Hesperian Massif, Spain. Recent detailed studies of the immediately underlying "Scyphocrinites Limestone'' unit reveal two levels of graptolites: a lower marly shale band with poorly preserved but large numbers of Pristiograptus dubius (s.l.), Colonograptus? cf. parultimus, and Linograptus sp., and a limestone band near the top of the unit yielding specimens of C.? transgrediens preserved in relief. In the Barrancos area of the Ossa Morena Zone of Portugal, a recently sampled 8 m thick section of shales and shales and sandstones has yielded six bands of graptolites, the lowest containing lower or middle Ludlow graptolites, and the three stratigraphically higher collections yielding the lower to middle Prídolí species Linograptus posthumus, Colonograptus? parultimus, C.? parultimus?, Monograptus formosus, and Monograptus bouceki, the last-named species occurring only in the highest collection and suggesting a mid-Prídolí age. The occurrence of Prídolí graptolites (Colonograptus? ultimus) is confirmed in the Sil syncline of the northernmost part of the Central Iberian Zone (northwestern Spain). Outside Iberia, but still within the southwestern European part of the North Gondwanan realm, Prídolí graptolites are known in the Armorican Massif of western France (Normandy and probably central Brittany), in Montagne Noire (southern France), and in southwestern Sardinia (Italy).
Constraints on the timing of thrusting during the Eurekan orogeny, Canadian Arctic Archipelago: an integrated approach to thermal history analysis
Authors: Arne D C , Zentilli M , Grist A M , Collins M
Published: October 2017

Thermochronological constraints on the timing of hanging-wall cooling across thrust faults can be interpreted in terms of fault movement under certain circumstances. Vitrinite reflectance data can be used to identify those circumstances and, in addition, provide constraints on the timing of fault movement relative to maximum paleotemperatures in the strata offset by faulting. Geological constraints and apatite fission track data from across the Vesle Fiord Thrust, Ellesmere Island, Canadian Arctic Archipelago, indicate that the initiation of fault movement occurred during the Paleocene, slightly older than predicted by plate-reconstruction models for compression during the Tertiary Eurekan orogeny, but in agreement with stratigraphic evidence for the onset of tectonism in the Sverdrup Basin. Vitrinite reflectance and fission track data further indicate that the strata affected by faulting attained their maximum paleotemperatures prior to deformation. The latter conclusion has important implications for hydrocarbon exploration at shallow levels in structural traps formed during the Eurekan orogeny.
Rate of Movement of Populations of Daphnia in Relation to Changes in Light Intensity
Authors: McNaught Donald C. , Hasler Arthur D.
Published: October 2017

A knowledge of the rate of vertical movement of a planktonic population is a prerequisite for the interpretation of the role that various factors play in depth control. A method for estimating this characteristic of a planktonic population of Daphnia is described. Several estimates of the net rate of movement have been determined within each of the four periods that characterize the migratory behavior of Daphnia in Lake Mendota, Wisconsin; a series of rates were calculated for each of 11 cruises of approximately 24-hr duration. In most cases, a linear relationship exists between the rate of vertical movement and the rate of change in the logarithm of the light intensity; a number of such relationships are summarized for three of the four periods of movement. An increase in the slope of this relationship with increasing temperature is evidence that the rate of movement in Daphnia is proportional to temperature. The consistent pattern of the rates of movement during the dawn rise and the subsequent regularity in timing of the morning maximum in relation to sunrise together provide the most striking aspect of the diel migration in Mendota. From the onset of the dawn rise, the rate of upward movement increases to a maximum at or slightly preceding sunrise and hence decreases to zero at the time of the morning maximum. Typically, the maximal rates do not exceed 1.5 m/hr. The mean morning maximum at the surface occurs 60.2 min following sunrise, with a standard deviation of 37.2 min; the mean evening maximum at the surface occurs 19.4 min before sunset, with a standard deviation of 61.0 min. Those morning maxima which deviate substantially from the mean were commonly formed under conditions of moderate to heavy cloud-cover. Behavioral evidence suggests a threshold of visual sensitivity of 10−4 to 10−5 lux for Daphnia. The mean amplitude of vertical movement characteristic of Daphnia in Mendota is 0.87 m, with a range from 0.29 m to 1.52 m. Comparative evidence supports the conclusion that the magnitude of the observed amplitudes of vertical movement are logical for an eutrophic lake such as Mendota. Aggregations of Daphnia at various levels present a problem in the design of a program to determine the periodicity of diel migration. Various types of aggregations are summarized within a framework of related environmental factors and with a description of the methods employed to meet the problem.
Anomalous Conditions in the Slope Water Area in 1959
Authors: Worthington L. V.
Published: October 2017

An oceanographic section made with the research vessel Crawford in June 1959 showed that the proportion of Labrador-Coastal Water to Slope Water at the meridian 57°30′W was unusually large. Data from this section combined with bathythermograms taken elsewhere in the Slope Water area and direct deep current measurements suggest that there was an abnormal influx of cold water from the Labrador Basin in 1959. This suggestion is strengthened by the high incidence of coastal fog in the summer of 1959. It is suggested that the cause of this influx was an abnormal North Atlantic weather pattern in January 1959.
On the Vertical Transport Velocity on Line "P" in the Eastern Subarctic Pacific Ocean
Authors: Acara A.
Published: October 2017

A method is given for calculating the vertical transport velocity in the sea, from the oceanographic observations at two close stations and a knowledge of the depth at which there is no net horizontal motion. This method is applied to Line "P" in the subarctic Pacific Ocean where the halocline structure exists, the bottom of the halocline being taken as the depth of no net motion.Such factors as the earth's rotation, the meridional transport, and the wind pattern, control the vertical transport velocity in a region. The wind defines the general meridional and vertical circulation pattern of the ocean.
Neotype of Argis lar Compared with Argis dentata (Crustacea, Decapoda)
Authors: Squires H. J.
Published: October 2017

The type specimens of Argis lar were collected in the north Pacific. They are no longer in existence. Specimens identified as A. lar by Rathbun, from the type locality and resembling the original specimens of Owen, are used to set up a neotype. This is done because some authors have assumed that specimens of Argis collected in the north Atlantic were A. lar and not A. dentata which they believed was not a valid species. Also the distribution of both species in northern Canadian waters is not yet clearly understood. Outstanding differences between the two species are discussed.
Cod Roe: Component Fatty Acids as Determined by Gas-Liquid Chromatography
Authors: Ackman R. G. , Burgher R. D.
Published: October 2017

The component fatty acids of cod roe resemble the flesh lipid fatty acids to a considerable degree. Comparison with the liver lipids of male and female fish suggests that less essential longer-chain monounsaturated fatty acids from the liver depot fat are metabolized by the female for the synthesis of particular fatty acids required by the developing eggs.
Tributary Homing of Sockeye Salmon at Brooks and Karluk Lakes, Alaska
Authors: Hartman Wilbur L. , Raleigh Robert F.
Published: October 2017

The degree of preference of sockeye salmon (Oncorhynchus nerka) for spawning in specific tributaries to Brooks and Karluk Lakes, Alaska, was studied in 1960 and 1961. Adult sockeye salmon begin to congregate around stream mouths soon after entering these lakes. At Brooks Lake, groups of fish were seined from various stream mouths and marked with distinctive tag color combinations. One group of tagged fish from each seine haul was released back into the original donor congregation as a control, and one or more groups were transported and released into congregations around other tributary mouths. Strength of tributary preference was determined by comparing the number of fish from each group distributed on the various spawning grounds. Eighty-three per cent of the 958 fish tagged were recovered at weirs and on stream and lake surveys. Distribution to spawning areas of sockeye salmon in control and transported groups was virtually identical. The study at Brooks Lake was followed by a study at Karluk Lake to explore further the strength of tributary preference. Very few sockeye salmon experimentally prevented from entering their preferred tributary chose an alternative spawning area. Most continued to attempt to enter their blocked tributary until death. A final study at Karluk Lake confirmed the fact that sockeye salmon entering the lake were predisposed to spawn in a particular tributary and could not be conditioned to enter an alternative tributary. We conclude that sockeye salmon are indeed homing to particular tributaries in these small lakes. The biological and management implications of these findings are discussed.
Marine Ostracods from the Plankton of Indian Arm, British Columbia, Including a Diminutive Subspecies Resembling Conchoecia alata major Rudjakov
Authors: McHardy R. A.
Published: October 2017

Four species of ostracods from Indian Arm, British Columbia, are characterized. Paradoxostoma striungulum Smith and Conchoecia elegans Sars, have variations not previously described. Philomedes sp., closely related to P. carcharodonta Smith, was represented by only one specimen. The fourth ostracod is one-third smaller than specimens of similar description which were obtained from the Pacific Ocean Weather Station "P" and which resemble most closely C. alata major Rudjakov. This smaller ostracod is proposed as a new subspecies, C. alata minor.
Angling License Sales from Northwest Territories, Canada, with Special Reference to Great Slave Lake
Authors: Keleher J. J.
Published: October 2017

not available
The Biology of Bothrimonus (=Diplocotyle) (Pseudophyllidea: Cestoda): Detailed Morphology and Fine Structure
Authors: Burt M. D. B. , Sandeman I. M.
Published: October 2017

Light and electron microscopy were used to describe the functional morphology of Bothrimonus sturionis in detail. In particular, the musculature, nervous system, osmoregulatory system, and tegument are dealt with, and the findings compared with those of other workers. The musculature of the scolex consists of several interrelated systems, the structure of each being discussed in relation to its function. Associated with the regular nervous system, considered typical of cestodes, is an extensive system of giant nerve fibers. The osmoregulatory system is unusual in that there are lateral "excretory" pores in many proglottides which open directly to the exterior of the worm. The microtriches of the tegument are long, like those of other primitive cestodes, and are covered by a noncellular sheath while the worm is in its gammarid host. The sheath is lost when the worm becomes established in its fish host; the nature and function of the sheath are discussed.
Annual Biodeposition and Gross Energy Budget of Mature Pacific Oysters, Crassostrea gigas
Authors: Bernard F. R.
Published: October 2017

The mean annual volume of seawater pumped by Pacific oysters in Departure Bay, British Columbia is 1488 liters/g per year. The energy requirement for metabolism and pumping is 1.74 cal/liter, while the mean annual caloric content of the seawater is 60.4 cals/liter. Annual biodeposition is 8.9 g/g per year; these data applied to a mean biomass of 190 g/m2 for a mature oyster reef show that 22,052 kcal are theoretically available for ingestion, but only 11% are retained, mostly to be biodeposited. The biodeposits have a caloric value of 1545 kcal/m2 and furnish an important nutritional substrate. Another important contribution to the food web is the annual release of gametes, equivalent to 502 kcal/m2 reef.
Residues of DDT in Lake Trout (Salvelinus namaycush) and Coho Salmon (Oncorhynchus kisutch) from the Great Lakes
Authors: Reinert Robert E. , Bergman Harold L.
Published: October 2017

Concentrations of DDT residues were higher in lake trout (Salvelinus namaycush) from southern Lake Michigan in 1966–70 (average 18.1 ppm in fish 558–684 mm long) than in lake trout of the same size-class from Lake Superior in 1968–69 (4.4 ppm), and higher in adult coho salmon (Oncorhynchus kisutch) from Lake Michigan in 1968–71 (averages for different year-classes, 9.9–14.0 ppm) than in those from Lake Erie in 1969 (2.2 ppm). Residues were significantly higher in lake trout from southern Lake Michigan than in those from the northern part of the lake. In lakes Michigan and Superior, the levels increased with length of fish and percentage oil. In Lake Michigan coho salmon, the residues remained nearly stable (2–4 ppm) from September of the 1st yr of lake residence through May or early June of the 2nd yr, but increased three to four times in the next 3 mo. Residues in Lake Erie coho salmon did not increase during this period, which preceded the spawning season. Although the concentrations of total residues in whole, maturing Lake Michigan coho salmon remained unchanged from August 1968 until near the end of the spawning season in January 1969, the residues were redistributed in the tissues of the spawning-run fish; concentrations in the loin and brain were markedly higher in January than in August. This relocation of DDT residues accompanied a marked decrease in the percentage of oil in the fish, from 13.2 in August to 2.8 in January. Concentrations of residues were relatively high in eggs of both lake trout (4.6 ppm) and coho salmon (7.4–10.2 ppm) from Lake Michigan. The percentage composition of the residues (p,p′DDE, o,p′/DDT, p,p′DDT, and p,p′DDT) did not differ significantly with life stage, size, age, or locality, or date of collection of lake trout or coho salmon.
An Acoustic Estimate of the Escapement of Sockeye Salmon (Oncorhynchus nerka) into Lake Washington in 1971
Authors: Thorne Richard E. , Dawson James J.
Published: October 2017

The feasibility of estimating the escapement of sockeye salmon (Oncorhynchus nerka) into Lake Washington by hydroacoustics was explored during 1971. Surveys were made of large fish targets within the lake just before and after the spawning migration of sockeye salmon up the Cedar River. A decrease was observed after the spawning migration comparable to the estimated escapement as determined by weir counts and spawning ground surveys.
Trace Metals in Lake Cayuga Lake Trout (Salvelinus namaycush) in Relation to Age
Authors: Tong Steven Shap Chow , Youngs William D. , Gutenmann Walter H. , Lisk Donald J.
Published: October 2017

Chromium concentration increased and molybdenum and tin concentrations decreased in Lake Cayuga lake trout (Salvelinus namaycush) from age 1 to 12 yr. The concentration of the rare element rhodium ranged from about 100 to 200 ppb. The concentrations of 33 other trace metals in the fish are reported.
Cloning and characterization of dispersed repetitive DNA derived from microdissected sex chromosomes ofRumex acetosa
Authors: Mariotti Beatrice , Navajas-Pérez Rafael , Lozano Rafael , Parker John S , de la Herrán Roberto , Rejón Carmelo Ruiz , Rejón Manuel Ruiz , Garrido-Ramos Manuel , Jamilena Manuel
Published: October 2017

Rumex acetosa is characterized by a multiple chromosome system (2n = 12 + XX for females, and 2n = 12 + XY1Y2for males), in which sex is determined by the ratio between the number of X chromosomes and autosome sets. For a better understanding of the molecular structure and evolution of plant sex chromosomes, we have generated a sex chromosome specific library of R. acetosa by microdissection. The screening of this library has allowed us to identify 5 repetitive DNA families that have been characterized in detail. One of these families, DOP-20, has shown no homology with other sequences in databases. Nevertheless, the putative proteins encoded by the other 4 families, DOP-8, DOP-47, DOP-60, and DOP-61, show homology with proteins from different plant retroelements, including poly proteins from Ty3-gypsy- and Ty1-copia-like long terminal repeat (LTR) retroelements, and reverse transcriptase from non-LTR retro elements. Results indicate that sequences from these 5 families are dispersed throughout the genome of both males and females, but no appreciable accumulation or differentiation of these types of sequences have been found in the Y chromosomes. These repetitive DNA sequences are more conserved in the genome of other dioecious species such as Rumex papillaris, Rumex intermedius, Rumex thyrsoides, Rumex hastatulus, and Rumex suffruticosus, than in the polygamous, gynodioecious, or hermaphrodite species Rumex induratus, Rumex lunaria, Rumex con glom er atus, Rumex crispus, and Rumex bucephalo phorus, which supports a single origin of dioecious species in this genus. The implication of these transposable elements in the origin and evolution of the heteromorphic sex chromosomes of R. acetosa is discussed.Key words: Rumex acetosa, sex chromosomes, microdissection, evolution, retroelements.
A CR1 element is embedded in a novel tandem repeat (HinfI repeat) within the chicken genome
Authors: Li Juan , Leung Frederick C
Published: October 2017

Highly repetitive DNA sequences constitute a significant portion of most eukaryotic genomes, raising questions about their evolutionary origins and amplification dynamics. In this study, a novel chicken repetitive DNA family, the HinfI repeat, was characterized. The basic repeating unit of this family displays a uniform length of 770 bp, which was defined by the recognition site of HinfI. The HinfI repeat was specifically localized in the pericentric region of chromosome 4 by fluorescence in situ hybridization and constitutes 0.51% of the chicken genome. Interestingly, a chicken repeat 1 (CR1) element has been identified within this basic repeating unit. Like other CR1 elements, this CR1 element also displays typical retrotransposition characteristics, including a highly conserved 3′ region and a badly truncated 5′ end. This direct evidence from sequence analysis, together with our Southern blot results, suggests that the HinfI repeat may originate from a unique region containing a retrotransposed CR1 element.Key words: satellite DNA, CR1 retrotransposon, HinfI repeat, Gallus gallus.
A genetic linkage map for hazelnut (Corylus avellanaL.) based on RAPD and SSR markers
Authors: Mehlenbacher Shawn A , Brown Rebecca N , Nouhra Eduardo R , Gökirmak Tufan , Bassil Nahla V , Kubisiak Thomas L
Published: October 2017

A linkage map for European hazelnut (Corylus avellana L.) was constructed using random amplified polymorphic DNA (RAPD) and simple sequence repeat (SSR) markers and the 2-way pseudotestcross approach. A full-sib population of 144 seedlings from the cross OSU 252.146 × OSU 414.062 was used. RAPD markers in testcross configuration, segregating 1:1, were used to construct separate maps for each parent. Fifty additional RAPD loci were assigned to linkage groups as accessory markers whose exact location could not be determined. Markers in intercross configuration, segregating 3:1, were used to pair groups in one parent with their homologues in the other. Eleven groups were identified for each parent, corresponding to the haploid chromosome number of hazelnut (n = x = 11). Thirty of the 31 SSR loci were able to be assigned to a linkage group. The maternal map included 249 RAPD and 20 SSR markers and spanned a distance of 661 cM. The paternal map included 271 RAPD and 28 SSR markers and spanned a distance of 812 cM. The maps are quite dense, with an average of 2.6 cM between adjacent markers. The S-locus, which controls pollen-stigma incompatibility, was placed on chromosome 5S where 6 markers linked within a distance of 10 cM were identified. A locus for resistance to eastern filbert blight, caused by Anisogramma anomala, was placed on chromosome 6R for which two additional markers tightly linked to the dominant allele were identified and sequenced. These maps will serve as a starting point for future studies of the hazelnut genome, including map-based cloning of important genes. The inclusion of SSR loci on the map will make it useful in other populations.Key words: Corylus avellana, hazelnut, filbert, linkage map, pseudotestcross, pollen-stigma incompatibility, random amplified polymorphic DNA, simple sequence repeat, microsatellite.
A global view of genetic diversity in cultivated sorghums using a core collection
Authors: Deu M , Rattunde F , Chantereau J
Published: October 2017

We report here an analysis of the structure of genetic diversity in cultivated sorghums. A core collection of 210 landraces representative of race, latitude of origin, response to day length, and production system was analysed with 74 RFLP probes dispersed throughout the genome. Multivariate analyses showed the specificity of the subrace guinea margaritiferum, as well as the geographical and racial pattern of genetic diversity. Neighbour-joining analysis revealed a clear differentiation between northern and southern equatorial African accessions. The presence of Asian accessions in these 2 major geographical poles for sorghum evolution indicated two introductions of sorghum into Asia. Morphological race also influenced the pattern of sorghum genetic diversity. A single predominant race was identified in 8 of 10 clusters of accessions, i.e., 1 kafir, 1 durra, 4 guinea, and 2 caudatum clusters. Guinea sorghums, with the exception of accessions in the margaritiferum subrace, clustered in 3 geographical groups, i.e., western African, southern African, and Asian guinea clusters; the latter two appeared more closely related. Caudatum were mainly distributed in 2 clusters, the African Great Lakes caudatum cluster and those African caudatum originating from other African regions. This last differentiation appears related to contrasting photoperiod responses. These results aid in the optimization of sampling accessions for introgression in breeding programs.Key words: sorghum, core collection, genetic diversity, RFLP.
An approach for isolating high-molecular-weight glutenin subunit genes using monoclonal antibodies
Authors: Wang H Q , Zhang X Y
Published: October 2017

High-molecular-weight glutenin subunits (HMW-GSs) play an important role in the breadmaking quality of wheat flour. In China, cultivars such as Triticum aestivum 'Xiaoyan No. 6' carrying the 1Bx14 and 1By15 glutenin subunits usually have attributes that result in high-quality bread and noodles. HMW-GS 1Bx14 and 1By15 were isolated by preparative sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and used as an antigen to immunize BALB/c mice. A resulting monoclonal antibody belonging to the IgG1 subclass was shown to bind to all HMW-GSs of Triticum aestivum cultivars, but did not bind to other storage proteins of wheat seeds in a Western blot analysis. After screening a complementary DNA expression library from immature seeds of 'Xiaoyan No. 6' using the monoclonal antibody, the HMW-GS 1By15 gene was isolated and fully sequenced. The deduced amino acid sequence showed an extra stretch of 15 amino acid repeats consisting of a hexapeptide and a nonapeptide in the repetitive domain of this y-type HMW subunit. Bacterial expression of a modified 1By15 gene, in which the coding sequence for the signal peptide was removed and a BamHI site eliminated, gave rise to a protein with mobility identical to that of HMW-GSs extracted from seeds of 'Xiaoyan No. 6' via SDS-PAGE. This approach for isolating genes using specific monoclonal antibody against HMW-GS genes is a good alternative to the extensively used polymerase chain reaction (PCR) technology based on sequence homology of HMW-GSs in wheat and its relatives.Key words: wheat, HMW-GS, monoclonal antibody, immunoscreen.
Reproductive isolation due to the genetic incompatibilities betweenThrichomys pachyurusand two subspecies ofThrichomys apereoides(Rodentia, Echimyidae)
Authors: Borodin P M , Barreiros-Gomez S C , Zhelezova A I , Bonvicino C R , D'Andrea P S
Published: October 2017

We tested intrinsic reproductive isolation between 3 taxa of the South American caviomorph rodent Thrichomys (Rodentia, Echimyidae): T. pachyurus, T. apereoides subsp. apereoides and T. apereoides subsp. laurentius. They were mated in captivity and produced viable progeny. Some F1hybrid females were fertile, whereas all F1males were sterile. Histological examination revealed meiotic arrest at the primary spermatocyte stage. No sperm was detected in testes or epididymes. Electron microscopic analysis of surface spread synaptonemal complexes revealed a complete failure of chromosome pairing in F1hybrids of T. pachyurus with T. apereoides subsp. laurentius and T. apereoides subsp. apereoides. In the male hybrids between T. apereoides subsp. apereoides and T. apereoides subsp. laurentius, meiosis did not proceed beyond diplotene, although all of the chromosomes, including heteromorphic ones, paired in an orderly fashion. Backcross males with homomorphic karyotypes showed segregation in meiosis progression. This indicates that male hybrid sterility is due to genetic, but not chromosomal, incompatibility of the parental taxa.Key words: hybrid sterility, speciation, chromosome rearrangements, meiosis, spermatogenesis, synaptonemal complex, Thrichomys.
ATP-dependent chromatin remodeling in T cells1This article is part of Special Issue entitled Asilomar Chromatin and has undergone the Journal’s usual peer review process.
Authors: Wurster Andrea L. , Pazin Michael J.
Published: October 2017

One of the best studied systems for mammalian chromatin remodeling is transcriptional regulation during T cell development. The variety of these studies have led to important findings in T cell gene regulation and cell fate determination. Importantly, these findings have also advanced our knowledge of the function of remodeling enzymes in mammalian gene regulation. First we briefly present biochemical and cell-free analysis of 3 types of ATP dependent remodeling enzymes (SWI/SNF, Mi2, and ISWI) to construct an intellectual framework to understand how these enzymes might be working. Second, we compare and contrast the function of these enzymes during early (thymic) and late (peripheral) T cell development. Finally, we examine some of the gaps in our present understanding.
RNA interference in mammalian DNA methylation1This review is part of Special Issue entitled Asilomar Chromatin and has undergone the Journal’s usual peer review process.
Authors: Mann Jeffrey R. , Mattiske Deidre M.
Published: October 2017

RNAi and Dicer-dependent siRNAs are required for constitutive heterochromatin formation in fission yeast and for establishing DNA methylation at repetitive elements in plants. In the mammalian male germ line, DICER1-independent piRNAs are required for the full establishment of DNA methylation of dispersed repetitive transposable elements. However, in other mammalian cell types, no clear picture has yet emerged of the role of RNAi in establishing heterochromatin and DNA methylation. In mouse embryonic stem cells, which remain viable on loss of DICER1 and ablation of RNAi, while no firm evidence has been obtained for defective heterochromatin formation, there are indications of defective DNA methylation. The latter has been attributed to an indirect effect of reduced DNA methyltransferase (DNMT) activity due to a loss of miRNA-mediated gene regulation. However, it is unclear whether the reductions in DNMT activity were sufficient to affect DNA methylation. We consider it equally likely that the defects in DNA methylation that can be observed in DICER1-deficient embryonic stem cells are the result of nonspecific effects related to RNAi loss aside from reduced DNMT activity.
Effect of temperature modulation on the onset of stationary convection in a rotating sparsely packed porous layer
Authors: Malashetty M S , Swamy M
Published: October 2017

The effect of temperature modulation on the onset of stationary convection in a Boussinesq fluid-saturated sparsely packed porous layer is investigated, when the porous layer is subjected to rotation about an axis parallel to the gravity vector. The linear stability analysis is used to study the effect of infinitesimal disturbances. The onset criterion is derived using perturbation expansion in powers of the small amplitude of the applied temperature field. The critical correction Rayleigh number is found to be a function of the frequency of modulation, the Taylor number, the Darcy number, the Prandtl number, and the viscosity ratio. The interaction of rotation and thermal modulation is studied. It is found that the rotation reinforces the effect of thermal modulation. The large-frequency symmetric modulation, asymmetric modulation, and bottom-wall temperature modulation stabilizes the system compared with the unmodulated system, while small-frequency symmetric modulation destabilizes it. The effect of the Darcy number, the Prandtl number, and the viscosity ratio on the stability of the system is also discussed.PACS No.: 47.55.Pb
Regular and singular solutions for charged dust distributions in the Einstein-Maxwell theory
Authors: Horvat D , Ilijić S
Published: October 2017

Solutions for the static spherically symmetric extremally charged dust in the Majumdar–Papapetrou system have been found. For a certain amount of the allocated mass and (or) charge, the solutions have singularities of a type that could render them physically unacceptable, since the corresponding physically relevant quantities are singular as well. These solutions, with a number of zero-nodes in the metric tensor, are regularized through the δ-shell formalism, thus redefining the mass and (or) charge distributions. The bifurcating behaviour of regular solutions found before is no longer present in these singular solutions, but quantized-like behaviour in the total mass is observed. The spectrum of regularized solutions restores the equality of the Tolman–Whittaker and Arnowitt–Deser–Misner (ADM) mass, as well the equality of the net charge and ADM mass, which is the distinctive feature of Majumdar–Papapetrou systems.PACS No.:04.40.Nr
Spontaneous emission inhibition from a driven four-level atom in a photonic band gap material
Authors: Zhang H , Liu G Q , Zhang H Z
Published: October 2017

Two models (an upper levels coupling model and a lower levels coupling model) of a four-level atom embedded in a double-band photonic crystal are adopted. The effect of spontaneous emission cancellation of such systems embedded in different reservoirs are investigated. Especially, the "trapping conditions" of such systems in photonic band gap (PBG) reservoirs are discussed for the first time. We also investigate the different quantum interference effects of the lower levels coupling model embedded in an isotropic PBG reservoir. It is interesting that when the trapping conditions are fulfilled, the additional peaks, which result from the contribution of the additional singularities of Laplace transform of the delayed Green function of the isotropic PBG modes, are eliminated.PACS Nos.: 42.50.Gy, 42.50.Ct, 42.70.Qs
Physics of particle collisions at high energies: Limits to phenomenology, Part 1
Authors: Sau G , Biswas S K , De B , Guptaroy P , Bhattacharya A , Bhattacharyya S
Published: October 2017

Interpretation and understanding of high-energy PP data in a clear, consistent, and comprehensive manner is crucial for making valid claims to build up any successful theoretical framework for particle interactions. We have tried here to analyze the various sets of PP data available from the pre-ISR days to the latest PP collisions at the relativistic heavy ion collider (RHIC) experiment at [Formula: see text] = 200 GeV in the light of a power-law model. Both mid-rapidity and high-rapidity data sets have been dealt with by applying the same working formula. It is found that the working formula used provides a good description of these wide ranging data sets; but hardly throws any deep insights into the nature of particle interactions that force us to question the worth and rigour of phenomenological studies.PACS Nos.: 13.60.Hb, 13.60.Le, 13.85.Ni
Phased Bessel functions
Authors: Hu X , Wang H , Guo D -S
Published: October 2017

In the study of photon-state transitions, we found a natural extension of the first kind of Bessel functions that extends both the range and domain of the Bessel functions from the real number field to the complex number field. We term the extended Bessel functions as phased Bessel functions. This extension is completely different from the traditional “analytical extension”. The new complex Bessel functions satisfy addition, subtraction, and recurrence theorems in a complex range and a complex domain. These theorems provide short cuts in calculations. The single-phased Bessel functions are generalized to multiple-phased Bessel functions to describe various photon-state transitions.PACS Nos.: 02.30.Gp, 32.80.Rm, 42.50.Hz
Spikes in ring-type events from ultra relativistic nuclear collisions
Authors: Ghosh D , Deb A , Lahiri M B , Bhattacharya A
Published: October 2017

This paper reports the observation of some peculiar ring-like events in ultra relativistic nuclear interactions (the 32S–AgBr interaction at 200 A GeV and the 16O–AgBr interaction at 60 A GeV). These events have been analysed in the light of Čerenkov gluon radiation as proposed by Dremin. Also the value of the refractive index of the nuclear matter is calculated. The analysis shows values of refractive index different from that revealed in normal nuclear matter. PACS Nos.: 25.75.–q, 24.60.Ky, 12.40.Ee
OH A2Σ+ –X2Π band ratios observed in the mesosphere by OSIRIS
Authors: Gattinger R L , Degenstein D A , Llewellyn E J , Stevens M H
Published: October 2017

In this study, we present spectra of the mesospheric OH A2Σ+ –X2Π band system, including the 0–0, 1–1, and 1–0 bands, as observed by OSIRIS (Optical Spectrograph and Infrared Imaging System). Spectral components due to Rayleigh-scattered sunlight, lower thermospheric dayglow emission features, and baffle scatter have been removed to isolate the OH emission signature. The observed spectra are compared with model spectra assembled using rotational emission rate factors for solar resonance fluorescence (g-factors) plus prompt emission of the OH A2Σ+ –X2Π band system from solar Lyman-α photodissociation of water. The observed band ratios are in good agreement with the model values. The altitude variation of the 0–0 band, relative to the 1–1 band, is in agreement with model predictions based on vibrational energy transfer from OH A2Σ+ ν′ = 1 to OH A2Σ+ ν′ = 0. This detailed understanding of the OH A2Σ+ –X2Π system is critical for the successful application of OH observations to the determination of mesospheric OH densities and water vapor concentrations.PACS Nos.: 33.20.Lg, 33.20.Tp, 33.70.Fd, 92.60.hc, 92.60.hw
The orbit-method solution for deformed three coupled scalar fields
Authors: Sadeghi J , Amani A R , Pourdarvish A
Published: October 2017

By using the orbit method we obtain deformed solutions for systems of three coupled scalar fields with super-potential W(ϕ1, ϕ2, ϕ3). At the first, we deform the corresponding super-potential and obtain defect solutions. We show how to construct new models together with the defect solutions in terms of the nondeformed model. Therefore, we draw the graph of super-potential and different fields in terms of x. So we observe that the graphs for deformed and nondeformed cases are changed by the scale.PACS Nos.: 11.10.–z, 11.10.Lm, 11.27.+d
Theory of surface light-induced drift with forced specularity
Authors: Goodman F O
Published: October 2017

Waxman has recently proposed new mechanisms for surface light-induced drift (SLID), which he called “SLID with forced specularity” (christened SLIDWFS here). SLIDWFS was proposed for its potential use in modelling several important physical processes; examples are selective control of spatial distributions of gases, including isotope separation, probing the molecule-surface interaction potential in gas-surface scattering, heterogeneous chemical reactions in catalysis, and laser cooling. Waxman’s cell geometry consisted of a single flat plate; the usual approximations were made in the analysis, and substantial effects (larger than in ordinary SLID) were reported. In the present contribution, we study the more realistic double-flat-plate and circular-cylindrical geometries. We get exact analytical solutions to the model rate equations, with results quite different from Waxman’s. For example, for circular-cylindrical geometry, which is clearly preferable in ordinary SLID, we predict a negligible SLIDWFS effect.PACS Nos.: 05.60.–k, 34.35.+a, 34.50.Rk
Electron paramagnetic resonance studies of the E′ centers in alpha-quartz
Authors: Perlson B D , Weil J A
Published: October 2017

Room-temperature electron paramagnetic resonance (EPR) studies (at ca. 9.85 GHz) of γ- and x-irradiated alpha-quartz are reported and discussed. The previously described E′2 center has been proved to be associated with hydrogen, and this center’s primary silicon-29 hyperfine coupling matrix has now been accurately determined, as were its hydrogen hyperfine coupling and electronic Zeeman splitting (g) matrices. The paramagnetic center is believed to arise from attack on a diamagnetic oxygen-anion vacancy V(O0) (E center) effectively by an electron and a proton arising from atomic hydrogen produced in the irradiation process. A second very similar center, called E′2(II) herein, was discovered and its parameter matrices too have been obtained by EPR, and it was modelled as described herein. It is proposed that the proton in E′2 resides on an oxygen anion adjacent to the vacancy species. Comparison is made of the spin-Hamiltonian parameter matrices and the choice of best symmetry-related sites expressing them, for the various centers E′1–E′4. PACS Nos.: 76.30.–v,61.72.Hh, 76.30.Mi, 42.70.Ce, 61.80.–x, 61.72.–y
Magnetic Properties of the Random Mixture of Ising Spins
Authors: Katsura Shigetoshi , Matsubara Fumitaka
Published: October 2017

A method of obtaining the magnetic properties of the random mixture of plural kinds of magnetic atoms (including nonmagnetic atoms) in both the site and the bond problems is presented. The specific heats and the susceptibilities of the one-dimensional binary mixture and the binary Bethe lattice are exactly given. The phase transitions of both the Bethe lattice and the ordinary two- and three-dimensional lattices are also discussed. It is shown that the phase boundary of an ordinary binary mixture in the site problem is rather similar to that in the bond problem when JAAJBB > 0 and JαJβ > 0, while they are quite different when JAAJBB < 0 and JαJβ < 0. In the latter case, the two critical lines of ordinary lattice, on which the uniform or the staggered susceptibility diverges, cross at some value of concentration of magnetic atoms, while they are separated by the paramagnetic phase in the bond problem. The experimental result for (MnxCr1−x)Sb is similar to the former and that for Co(SxSe1−x)2 is similar to the latter.
Levels in 45Sc from Radiative Proton Capture in 44Ca
Authors: Schulte R. L. , King J. D. , Taylor H. W.
Published: October 2017

A total of 22 resonances has been observed in the 44Ca(p,γ)45Sc reaction within the incident proton energy range of 600 to 930 keV. Gamma-ray singles spectra and γ-ray angular distribution data were accumulated for resonances at Ep = 856 and 906 keV. Both of these resonant states have been found to have spin 3/2. The measured angular distributions of primary γ rays from the resonant states have given spin information on the intermediate bound states of 45Sc with excitation energies above 2 MeV. A γ-ray decay scheme has been derived from the γ-ray spectra. The data indicate new levels at 2151.0, 3525.2, 3548.5, 3584.0, and 3714.3 keV.
Radio Propagation Measurements of Auroral Ionization Using Rocket-Borne Transmitters
Authors: Forsyth P. A. , Palmer F. H.
Published: October 2017

Three rockets carrying radio propagation experiments were launched respectively into the prebreakup, breakup, and postbreakup phases of auroral displays during early 1968. The radio measurements, which provide information concerning the three-dimensional spatial gradients in ionization, show quite different characteristics for the three occasions. In the first two it seems that the configuration of ionization was essentially similar to that of the visible aurora. In the third, during a widespread homogeneous auroral glow, the ionization showed weak small-scale irregularities, possibly generated locally by plasma instabilities. Data from a ground-based photometer and from particle precipitation experiments aboard two of the rockets are also compared with the radio evidence.
Measurements of Ionospheric Absorption Using Radio Reflections from Meteors
Authors: Abdu M. A. , Vogan E. L. , Forsyth P. A.
Published: October 2017

An earlier note by Chu, Vogan, and Forsyth suggested the use of a two-frequency meteor scatter system for the measurement of ionospheric absorption, particularly when the absorbing layer is sufficiently patchy to render conventional riometer measurements inaccurate. A system, incorporating a novel method of signal comparison, has been tested between Winnipeg and London. It seems to offer specific advantages over a riometer for specialized studies of rapidly varying absorption, but in its present form has certain defects which should be remedied in any system intended for routine use.
Preparation and Properties of Amorphous Tl2SexTe1−x Films
Authors: Harris J. J. , Brodie D. E. , Eastman P. C.
Published: October 2017

Films of amorphous Tl2SexTe1−x, with x values of 0, 0.25, 0.5, 0.75, and 1, have been prepared by flash evaporation of mixed powders of Tl2Se and Tl2Te. These films show thermally activated conduction with up to four distinct activation energies, in different temperature ranges, as the samples are warmed from their liquid-nitrogen growth temperature; they then undergo spontaneous recrystallization at temperatures near 300 K. The low-temperature conduction in these samples is consistent with the model of amorphous semiconductors proposed by Davis and Mott, and the compositional dependence of the parameters of this model are presented and discussed.