bluuebunny/crossref_metadata_2025 huggingface dataset:
Immobilization of mycotoxins on modified nanodiamond substrates
Authors: Gibson N. M. , Luo T. J. M. , Brenner D. W. , Shenderova O.
Published: February 2012

The effectiveness of modified nanodiamonds (NDs) for the adsorption of mycotoxins, aflatoxin B1 (AfB1) and ochratoxin A (OTA), are investigated in this paper. Binding and release mechanisms of the mycotoxins were addressed using an assortment of NDs modified by different surface treatments, including carboxylation, hydrogenation and hydroxylation, followed by isolating NDs of different sizes. Results indicate that AfB1 adsorption on NDs is directly related to aggregate size, whereas OTA adsorption is primarily centered upon electrostatic interactions that depend on the types of surface functional groups on the ND. Findings show that modified NDs with small aggregation sizes (~40 nm) have greater adsorption capacities for AfB1 than yeast cells walls and untreated NDs from various vendors, but comparable to activated charcoal. In OTA studies, positively charged NDs outperformed clay minerals, which are well-known and efficient sorbents for mycotoxins. Furthermore, ND adsorption capacities can be preserved in a wide range of pH.
Stress mapping in strain-engineered silicon p-type MOSFET device: A comparison between process simulation and experiments
Authors: Krzeminski Christophe D.
Published: February 2012

Strain engineering is the main technological booster used by semiconductor companies for the 65 and 45 nm technology nodes to improve the transistor channel mobility and the electrical performance of logic devices. For 32 and 22 nm nodes, intense research work focuses on the integration and optimization of these different techniques by accumulating the effects of different stressors. Estimating the level and the distribution of the stress field generated in the channel by the fabrication process is a complex issue. The process simulation has a key role to play in order to face the many challenges associated with the stress engineering approach in terms of scalability, yield, and design. The objective of this paper is first to evaluate the stress distribution generated by the two most usual processing steps: contact etch stop liner and embedded SiGe stressors. Next, the final stress field in nanoscale device resulting of these intentional stress sources are evaluated. Process simulation has been able to quantify the global trend observed in relatively close correlation with several experimental studies.
Advanced nanodiamond emitter with pyramidal tip-on-pole structure for emission self-regulation
Authors: Wisitsora-at Anurat , Hsu Shao-Hua , Kang Weng P. , Davidson Jimmy L. , Tuantranont Adisorn
Published: February 2012

In this paper, we report an innovative nanodiamond field emitter structure consisting of an individual pyramidal tip sitting on top of a ballast resistor “pole.” The tip-on-pole nanodiamond structures are fabricated by a new mold transfer process that is comprised of reactive-ion-etching of 3.5 μm-thick thermal oxide on Si substrate, anisotropic etching of Si, tip sharpening by thermal oxidation and chemical vapor deposition of nanodiamond. The fabricated tip-on-pole nitrogen-incorporated nanodiamond emitter exhibits a low turn-on electric field of 3.5 V/um and a very high emission current density of ∼1.7 A/cm2 at an electric field of ∼7.5 V/um. Analysis of the emission current based on Fowler–Nordheim theory indicates a current regulated regime due to the pole-structured ballast resistor with the resistance value of ∼140 kΩ. Thus, the diamond pole ballast resistor has proven to provide self-limiting of emission current that improves the total current density as well as the emission current stability of the pyramidal nanodiamond emitters. Therefore, the proposed tip-on-pole nanodiamond emitters show great promise for high current and power applications.
Influence of hydrogen on the thermionic electron emission from nitrogen-incorporated polycrystalline diamond films
Authors: Paxton W. F. , Howell M. , Kang W. P. , Davidson J. L.
Published: February 2012

Although hydrogen has been shown to enhance the thermionic emission properties of nitrogen-incorporated diamond cathodes, the effect diminishes when these cathodes are heated to temperatures in excess of 700 °C, possibly due to the hydrogen desorbing from the diamond. In order to further examine this behavior, this work examines the thermionic emission properties of a nitrogen-incorporated diamond film grown by chemical vapor deposition in a hydrogen-methane-nitrogen plasma. The film was tested for thermally stimulated electron emission at temperatures ranging from 500 to 900 °C in an as-grown state and after exposure to a hydrogen plasma treatment. Emission current increased, as described by the Richardson equation for thermal emission up to ∼ 700 °C. Above ∼ 800 °C the thermionic emission current was observed to diminish, an effect attributed to the loss of hydrogen from the diamond. Recovery of the hydrogen effect was explored by exposing the diamond film to a low-energy hydrogen plasma. The thermionic emission current at temperatures below ∼700 °C after this hydrogen plasma exposure was observed to increase by four orders of magnitude over the thermionic emission current observed in the initial (as-grown) test. Possible explanations for this emission current increase are discussed.
Surgical diseases of the genital tract in male dogs 1. Scrotum, testes and epididymides
Authors: de la Puerta Benito , Baines Stephen
Published: February 2012

While castration is the most common surgery carried out on the genitals of male dogs in first‐opinion practice, there are several other, less common, surgical procedures that are performed to treat various conditions affecting the male reproductive tract. This article discusses the surgical diseases and treatment of the scrotum, testes and epididymides of dogs. A second article, to be published in the March issue ofIn Practice, will cover the surgical techniques used to manage disorders of the penis and prepuce.
Gastrointestinal disease in rabbits 1. Gastric diseases
Authors: Lord Brigitte
Published: February 2012

Gastrointestinal diseases in rabbits are being recognised with increasing frequency. A pet rabbit presented with anorexia, weight loss, changes in defecation and depression can present a diagnostic and therapeutic challenge for the clinician. Diet‐ and stress‐related problems predominate, and preventive treatment plays a large role in managing these conditions. However, gastric ulceration and bacterial, viral, parasitic, idiopathic and neoplastic diseases are also seen frequently in pet rabbits. This article provides an overview of the common gastric conditions seen in rabbits, including their diagnosis and the options for treatment. The common causes, diagnosis and approach to the management of intestinal diseases will be discussed in an article to be published in the March issue of In Practice.
Abdominal ultrasonography as an adjunct to clinical examination 2. Cattle
Authors: Scott Phil
Published: February 2012

This article, the second of two discussing the use of abdominal ultrasonography as an adjunct to a thorough clinical examination in farm animal practice, describes ultrasonographic findings that might be visualised in the abdomen of cattle, with particular focus on the common problems encountered in the species. Part 1, published in the January issue of In Practice (volume 34, pages 12–21), considered ultrasonography of the abdomen in small ruminants.
Muscle and tendon disorders in small animals 2. Conditions affecting the hindlimb and digital flexor tendons
Authors: Moores Andy
Published: February 2012

A wide range of muscle and tendon conditions are seen in small animals. An article in the January issue of In Practice (volume 34, pages22–26) reviewed some general aspects of managing tendon and muscle disorders together with conditions affecting the forelimb. This article describes conditions affecting the hindlimb as well as digital flexor tendon injuries that affect both the fore‐ and hindlimbs.
Trouble with snow: preparing your vehicle for winter conditions
Authors: Richards Iain
Published: February 2012

Snow may be an opportunity for many people to have some fun, but it represents quite a different prospect for anyone who has to work in it. Practice managers have a duty to ensure that their staff remain safe when they are on farm visits or house calls. In this article, Iain Richards describes the hazards associated with bad weather and recommends some useful equipment to keep in the boot of your vehicle in case problems arise.
Analysis of expressed sequence tags in Brassica napus cotyledons damaged by crucifer flea beetle feeding
Authors: Gruber Margaret , Wu Limin , Links Matthew , Gjetvaj Branimir , Durkin Jonathan , Lewis Christopher , Sharpe Andrew , Lydiate Derek , Hegedus Dwayne
Published: February 2012

The molecular basis of canola ( Brassica napus L.) susceptibility to the crucifer flea beetle (FB, Phyllotreta cruciferae Goeze) was investigated by comparing transcript representation in FB-damaged and undamaged cotyledons. The B. napus cotyledon transcriptome increased and diversified substantially after FB feeding damage. Twenty-two genes encoding proteins with unknown function, six encoding proteins involved in signaling, and a gene encoding a B-box zinc finger transcription factor were moderately or strongly changed in representation with FB feeding damage. Zinc finger and calcium-dependent genes formed the largest portion of transcription factors and signaling factors with changes in representation. Six genes with unknown function, one transcription factor, and one signaling gene specific to the FB-damaged library were co-represented in a FB-damaged leaf library. Out of 188 transcription factor and signaling gene families screened for “early” expression changes, 16 showed changes in expression within 8 h. Four of these early factors were zinc finger genes with representation only in the FB-damaged cotyledon. These genes are now available to test their potential at initiating or specifying cotyledon responses to crucifer FB feeding.
Genetic map of lps3: a new short petiole gene in soybeans
Authors: Jun Tae-Hwan , Kang Sung-Taeg
Published: February 2012

The short petiole trait is valuable for the development of plant ideotypes with high yield by improving the plant canopy. The soybean breeding line SS98206SP has shown extremely short petioles in the greenhouse and fields. A new single recessive gene designated as lps3 confers the short petiole trait in SS98206SP. The objectives of this study were to map the short petiole gene in SS98206SP with PCR-based markers. In total, 187 F2 plants and their F2:3 families from a cross between the short petiole line SS98206SP and the long petiole cultivar ‘Taekwang’ along with the two parental lines were evaluated for their petiole lengths in a greenhouse. An SSR marker from each 10-cM section of a consensus soybean map was selected for bulked segregant analysis (BSA) to identify the tentative genomic location of the gene. The BSA technique was useful to localize the gene to a genomic region in the soybean linkage group F (chromosome 13). A linkage map with six SSR and two SNP markers flanking the gene was constructed. We positioned the gene between two SSR markers, Sat_234 and Sct_033, at distances of 8.5 and 3.5 cM from the marker, respectively. The makers flanking the gene (lps3) were located within 3–4 cM of the gene. These markers will be useful for maker-assisted selection in the development of new ideotype soybean plants.
Genome affinity and meiotic behaviour in trigenomic hybrids and their doubled allohexaploids between three cultivatedBrassicaallotetraploids andBrassica fruticulosa
Authors: Chen J.P. , Ge X.H. , Yao X.C. , Li Z.Y.
Published: February 2012

The wild species Brassica fruticulosa Cyr. (FF, 2n = 16) is closely related to the cultivated Brassica species. Through interspecific reciprocal crosses between B. fruticulosa and three cultivated Brassica allotetraploids (AABB, AACC, and BBCC where A = 10, B = 8, and C = 9), four trigenomic hybrids (F.AC, 2n = 27; F.AB, 2n = 26; F.BC, 2n = 25; BC.F, 2n = 25) were produced. By chromosome doubling of respective hybrids, three allohexaploids (FF.AACC, 2n = 54; FF.AABB, 2n = 52; BBCC.FF, 2n = 50) were synthesized. In pollen mother cells (PMCs) of the trigenomic hybrids, 1–2 autosyndetic bivalents were detected within A, B, and C genomes but only one within F genome; 1–3 allosyndetic bivalents between any two genomes were observed, and a closer relationship of F and B genomes than F and A genomes or F and C genomes was revealed. The allohexaploids showed a generally low but different pollen fertilities. The chromosomes in PMCs were predominantly paired as bivalents but some univalents and multivalents at variable frequencies were observed. The bivalents of homologous pairing for each genome prevailed, but allosyndetic quadrivalents and hexavalents involving any two genomes were observed, together with autosyndetic quadrivalents for A, B, and C genomes but not the F genome. The nondiploidized cytological behaviour of these allohexaploids contributed to their low fertility. The relationships between the genome affinity and meiotic behavior in these allohexaploids were discussed.
New robust passivity criteria for discrete-time genetic regulatory networks with Markovian jumping parameters
Authors: Mathiyalagan K. , Sakthivel R. , Anthoni S. Marshal
Published: February 2012

In this paper, we present some novel results for robust passivity of a class of uncertain discrete-time Markovian jumping genetic regulatory networks (GRNs) with time-varying delays. By constructing a new set of Lyapunov–Krasovskii functionals, together with the matrix inequality technique, we provide a new set of results for the passiveness, and also ensure the mean-square asymptotical stability (internally) of the considered GRNs about their equilibrium points for all time delays satisfying both the lower bound and upper bound of the interval time-varying delay. Further, the obtained results are extended to deal with the robust passiveness of the considered GRNs for all admissible uncertainties. The obtained conditions are derived in terms of linear matrix inequalities (LMIs), which can be easily verified via the LMI toolbox. Finally, numerical examples with simulation results are provided for the GRN model to illustrate the applicability and usefulness of the theory.
Kantowski–Sachs string cosmological model in f(R) theory of gravity
Authors: Adhav K.S.
Published: February 2012

The exact solutions of the field equations for a Kantowski–Sachs space–time filled with cosmic strings in the framework of f(R) gravity are derived. The physical behavior of the model is studied. The function f(R) of the Ricci scalar is also evaluated for the model. This model represents a continuously expanding shearing universe (from the start of the big bang) currently entering the phantom phase.
Kinetic and thermodynamic treatments of a neutral binary gas mixture affected by a nonlinear thermal radiation field
Authors: Abourabia Aly Maher , Abdel Wahid Taha Zakaraia
Published: February 2012

In the present study, the kinetic and the irreversible thermodynamic properties of a binary gas mixture, under the influence of a thermal radiation field, are presented from the molecular viewpoint. In a frame comoving with the fluid, the Bhatnagar–Gross–Krook model of the kinetic equation is analytically applied, using the Liu–Lees model. We apply the moment method to follow the behavior of the macroscopic properties of the binary gas mixture, such as the temperature and the concentration. The distinction and comparisons between the perturbed and equilibrium distribution functions are illustrated for each gas mixture component. From the viewpoint of the linear theory of irreversible thermodynamics we obtain the entropy, entropy flux, entropy production, thermodynamic forces, and kinetic coefficients. We verify the second law of thermodynamics and celebrated Onsager’s reciprocity relation for the system. The ratios between the different contributions of the internal energy changes, based upon the total derivatives of the extensive parameters, are estimated via Gibbs’ formula. The results are applied to the argon–neon binary gas mixture, for various values of both the molar fraction parameters and radiation field intensity. Graphics illustrating the calculated variables are drawn to predict their behavior and the results are discussed.
The power series technique and detection of zero-group velocity Lamb waves in a functionally graded material plate
Authors: Bouhdima M.S. , Zagrouba M. , Ben Ghozlen M.H.
Published: February 2012

This paper presents a technique for measuring the variation of the material properties along the thickness in a functionally graded material (FGM) plate. To investigate the propagation behavior of Lamb waves in a thermal stress relaxation type FGM plate with material parameters that vary continuously along the thickness, the power series technique, which has been proved to have good convergence and high precision, is employed for theoretical derivations. The method exploits the resonance at the minimum frequency of the S1 - zero group velocity (ZGV) mode. At this minimum frequency (f0), the group velocity vanishes, whereas the phase velocity remains finite. The numerical results also reveal differences between the ZGV frequency in the FGM plate and the corresponding frequency in a homogenous plate. In terms of results, we find that the in-plane and out-plane displacements are different between Al-rich and Si-rich surfaces. The plots of the involved stresses within the plate are added to check the performed calculations. Besides, the study covers the sensitivity of S1-ZGV resonance frequency to the FGM character and any slight variation of the plate thickness. All these results give theoretical guidance not only for experimental measurement of material properties but also for nondestructive evaluation using an ultrasonic wave generation device.
Modification of photonic crystals for obtaining common band gaps for TE and TM waves
Authors: Moghimi M. , Mirzakuchaki S. , Granpayeh N. , Nozhat N. , Darvish G.H.
Published: February 2012

The band gaps of the two-dimensional photonic crystals, created by inhomogeneous triangular photonic crystal of variable central hexagonal holes are derived. The structure is made of air holes in GaAs. We present the best absolute photonic band gap for this structure by changing the holes’ radii. The photonic band gaps are calculated by the plane wave expansion method. The results indicate 95% overlap in the band gaps of both polarizations of TE and TM in triangular lattice.
Exact solutions of Wick-type stochastic Korteweg – de Vries equation
Authors: Zhang Sheng
Published: February 2012

An algorithm is devised for using the compatibility method to find symmetries and similarity reductions of Wick-type stochastic partial differential equations. To illustrate the validity and advantages of the devised algorithm, the Wick-type stochastic Korteweg – de Vries equation is considered. With the aid of Hermite transformation and white noise theory, we obtain a symmetry and corresponding reduction of the Wick-type stochastic Korteweg – de Vries equation. Furthermore, some new similarity solutions are obtained including Jacobi elliptic function solutions, hyperbolic function solutions, and trigonometric function solutions.
Comment on “Generalization of Einstein’s synchronization for the case of anisotropic light speed”1Appears in Can. J. Phys. 87, 969.
Authors: Drory Alon
Published: February 2012

In a recent article, A. Sfarti attempted to derive the frame-invariance of the speed of light from the principle of relativity, thereby eliminating the second postulate from the foundations of special relativity (Can. J. Phys. 87, 969 (2009)). I analyse his derivation and conclude that it is incorrect.
On the invariances, conservation laws, and conserved quantities of the damped–driven nonlinear Schrödinger equation
Authors: Biswas Anjan , Masemola P. , Morris R. , Kara A.H.
Published: February 2012

We study the invariance, exact solutions, conservation laws, and double reductions of the nonlinear Schrödinger equation with damping and driving terms. The underlying equation is used to model a variety of resonant phenomena in nonlinear dispersive media, inter alia. For the purpose of our analysis, the complex equation is construed as a system of two real partial differential equations.
DISCUSSION ON EVENT HORIZON AND QUANTUM ERGOSPHERE OF DYNAMIC DE SITTER BLACK HOLES
Authors: LIU BAI SHENG , ZHANG JING YI
Published: February 2012

In the paper, the tunneling framework is applied to calculate the local horizons of Vaidya–de Sitter black holes and Vaidya–Bonner–de Sitter black holes. The researches show that the quantum ergosphere of a spherically symmetric black hole is identical with the potential barrier set by the tunneling process. The calculations also indicate that both the apparent horizons of the dynamic de Sitter black hole produce Hawking radiation. The conclusions can be applicable to either the charged or uncharged particles' Hawking radiation.
AdS–MAXWELL SUPERALGEBRA AND SUPERGRAVITY
Authors: DURKA R. , KOWALSKI-GLIKMAN J. , SZCZACHOR M.
Published: February 2012

In this paper we derive the anti-de Sitter counterpart of the super-Maxwell algebra presented recently by Bonanos et al. Then we gauge this algebra and derive the corresponding supergravity theory, which turns out to be described by the standard N = 1 supergravity Lagrangian, up to topological terms.
CENTROID TRIANGULATIONS FROM k-SETS
Authors: EL ORAIBY WAEL , SCHMITT DOMINIQUE , SPEHNER JEAN-CLAUDE
Published: February 2012

Given a set V of n points in the plane, no three of them being collinear, a convex inclusion chain of V is an ordering of the points of V such that no point belongs to the convex hull of the points preceding it in the ordering. We call k-set of the convex inclusion chain, every k-set of an initial subsequence of at least k points of the ordering. We show that the number of such k-sets (without multiplicity) is an invariant of V, that is, it does not depend on the choice of the convex inclusion chain. Moreover, this number is equal to the number of regions of the order-k Voronoi diagram of V (when no four points are cocircular).

The dual of the order-k Voronoi diagram belongs to the set of so-called centroid triangulations that have been originally introduced to generate bivariate simplex spline spaces. We show that the centroids of the k-sets of a convex inclusion chain are the vertices of such a centroid triangulation. This leads to the currently most efficient algorithm to construct particular centroid triangulations of any given point set; it runs in O(n log n + k(n - k) log k) worst case time.
MULTI COVER OF A POLYGON MINIMIZING THE SUM OF AREAS
Authors: ABU-AFFASH A. KARIM , CARMI PAZ , KATZ MATTHEW J. , MORGENSTERN GILA
Published: February 2012

We consider a geometric optimization problem that arises in sensor network design. Given a polygon P (possibly with holes) with n vertices, a set Y of m points representing sensors, and an integer k, 1 ≤ k ≤ m. The goal is to assign a sensing range, ri, to each of the sensors yi ∈ Y, such that each point p ∈ P is covered by at least k sensors, and the cost, [Formula: see text], of the assignment is minimized, where α is a constant.

In this paper, we assume that α = 2, that is, find a set of disks centered at points of Y, such that (i) each point in P is covered by at least k disks, and (ii) the sum of the areas of the disks is minimized. We present, for any constant k ≥ 1, a polynomial-time c1-approximation algorithm for this problem, where c1 = c1(k) is a constant. The discrete version, where one has to cover a given set of n points, X, by disks centered at points of Y, arises as a subproblem. We present a polynomial-time c2-approximation algorithm for this problem, where c2 = c2(k) is a constant.
SOLUTION OF THE MEMBERSHIP PROBLEM FOR CERTAIN RATIONAL SUBSETS OF ONE-RELATOR GROUPS WITH A SMALL CANCELLATION CONDITION
Authors: JUHÁSZ ARYE
Published: February 2012

Let n ≥ 2 be a natural number, X = { x1,…, xn} and let F be the free group, freely generated by X. Let R be a cyclically reduced word in F such that its symmetric closure [Formula: see text] in F satisfies the small cancellation condition C′(1/5) & T(4). Let G be the group presented by [Formula: see text]. A Magnus subsemigroup of G is any subsemigroup of G generated by at most 2n - 1 elements of [Formula: see text]. In this paper we solve the Membership Problem for rational subsets of G which are contained in a Magnus subsemigroup of G, provided that [Formula: see text] satisfies certain combinatorial conditions. We use small cancellation theory with word combinatorics.
STABLE MATCHED LAYER FOR THE ACOUSTIC CONSERVATION EQUATIONS IN THE TIME DOMAIN
Authors: HÜPPE ANDREAS , KALTENBACHER MANFRED
Published: February 2012

In recent years the development of free field radiation conditions in the time domain has become a topic of intensive research. Perfectly matched layer (PML) approaches for the frequency domain are well known. In the time domain, on the other hand, they suffer in many cases from highly increased complexity and instabilities. In this paper, we introduce a PML for the conservation equations of linear acoustics. The used formulation requires three auxiliary variables in 3D and circumvents thereby convolution integrals and higher order time derivatives. Furthermore, we prove the weak stability of the proposed formulation and show their good absorption properties by means of numerical examples.
MRI FINDINGS IN IDIOPATHIC GLUTEAL FIBROSIS
Authors: Jakkani Ravi Kanth , Sureka Jyoti , Panwar Sanuj , Shyam S.
Published: February 2012

Gluteal fibrosis is usually secondary to intramuscular injections and rarely can be idiopathic in nature. Clinically characterized by proximal muscle weakness and in advanced cases groove can be seen in gluteal regions. It can mimic with other conditions like muscular dystrophies and poliomyelitis. MRI is a very valuable tool in diagnosing this disorder and is also helpful to exclude other conditions.
MULTIFOCAL OSTEOARTICULAR TUBERCULOSIS PRESENTING AS OLIGOARTICULAR CHRONIC JUVENILE ARTHRITIS
Authors: Shyam S. , Sureka Jyoti , Jakkani Ravi Kanth
Published: February 2012

Osteoarticular tuberculosis of the bilateral ankle joint is a rare occurrence and diagnostic dilemmas are common, as it often mimics the inflammatory arthritis. We present a rare case of bilateral ankle tuberculosis in a young male patient presenting with ankle pain in the absence of systemic and pulmonary symptoms which mimicked oligoarticular chronic juvenile arthritis. Further evaluation with MRI of ankle and chest radiograph helped in making a presumptive diagnosis of tuberculosis, which was further confirmed by obtaining granulomatous tissue on bone biopsy. Despite multifocal osteoarticular involvement, the outcome of the patient was favorable after the treatment. Osteoarticular tuberculosis must be considered in patients with chronic oligoarticular or polyarticular involvement.
Mesozoic and Cenozoic evolution of salt structures within the Polish basin: An overview
Authors: Krzywiec Piotr
Published: February 2012

The Permian–Cretaceous Polish Basin belonged to the system of epicontinental depositional basins of Western and central Europe and was filled with several kilometres of siliciclastics, carbonates, and also thick Zechstein (approximately Upper Permian) evaporites. Its axial part (the so-called Mid-Polish Trough) characterized by the thickest Permo-Mesozoic sedimentary cover, developed above the Teisseyre–Tornquist Zone, lithospheric-scale boundary separating the East European Craton and the Palaeozoic Platform. The Polish Basin was inverted in Late Cretaceous–Paleocene times. A synthesis of studies based on seismic reflection data allowed some general rules regarding salt tectonics of the Polish Basin to be formulated. Two general classes of structures genetically related to the presence of the Zechstein evaporites have been described: peripheral structures located within NE and SW flanks of the Polish Basin, outside its axial part and structures located within its axial part. The first class of structures includes grabens bounded by listric faults detached above salt or salt pillows that developed where Zechstein evaporites were of relatively smaller thickness and where sub-Zechstein fault tectonics played a relatively smaller role. The second class of structures includes more mature salt structures such as salt pillows and salt diapirs and is related to the more axial part of the basin, characterized by relatively thicker Zechstein evaporites and by more intense basement tectonics. First salt movements (salt pillowing) took place in the Early Triassic that in certain cases was followed by the Late Triassic salt diapirism and extrusion. In Jurassic–Early Cretaceous times, no significant growth of salt structures took place. Most of the salt diapirs have been finally shaped by the Late Cretaceous inversion tectonics. Some salt diapirs also underwent Cenozoic reactivation, associated with localized Oligocene or Miocene subsidence that in some cases was followed by younger (Pliocene–Quaternary) inversion and uplift.
Regional-scale structural role of Permian salt within the Central European Basin System
Authors: Maystrenko Yuriy Petrovich , Bayer Ulf , Scheck-Wenderoth Magdalena
Published: February 2012

The Central European Basin System (CEBS) includes the former Northern and Southern Permian Basins together with superimposed Meso-Cenozoic sub-basins and contains a thick layer of Upper Permian (Zechstein) salt. This salt was mobilized in response to several post-Permian tectonic events. In order to analyse the regional relationship between the structural pattern of the Meso-Cenozoic sedimentary cover and the distribution of the Upper Permian salt, a 3D structural model of the CEBS has been constructed. In this model, the Permian salt is resolved as an extra layer for the entire basin system. According to the 3D structural model, the salt layer is strongly deformed as a result of halokinetic activity. The thickest salt is localized within salt walls and diapirs, reaching up to 9 km of thickness. A regional structural 3D analysis of the overburden in relation to underlying ductile salt demonstrates that the geometry of the sedimentary cover is strongly complicated by a variety of salt structures. The withdrawal of the Permian salt appears to have played a key role in both deposition and deformation of Meso-Cenozoic deposits in addition to tectonically forced regional subsidence.
Strain partitioning in gravity-driven shortening of a thick, multilayered evaporite sequence
Authors: Cartwright Joe , Jackson Martin , Dooley Tim , Higgins Simon
Published: February 2012

Three-dimensional seismic data from the Levant Basin, eastern Mediterranean, was used to quantify longitudinal strains in thick, multilayered Messinian evaporites at an early stage of salt tectonics. Gravity-spreading is driven by basin subsidence and tilting of the Levant margin and by progradation of the Nile Cone. Similar styles of shortening in two separate 3D survey areas comprise detachment folds, thrust-ramp folds and conjugate arrays of strike-slip faults. These Pleistocene structures can be explained with a single deformation phase with a tectonic transport direction of NE to ENE, obliquely opposed to the extension updip, which began in the Late Pliocene. Four major detachments within the Messinian are probably halite-rich intervals in the multilayer. Shortening of competent interlayers varies from 1–2% near the base to
c.
7% near the top of the Messinian, with a sharp reduction in shortening at the top Messinian and roof to 1–2%. This shortening profile is attributed to asymmetric Poiseuille flow, indicating that salt is flowing downdip faster than the overburden is translating. Physical modelling supports the inferred flow profile, showing that each mobile layer flows faster than adjoining competent layers and that strains in evaporites can be far greater than in the overburden. This is the first published use of seismic data to demonstrate the flow regime within salt on a regional scale.
3D seismic study of complex intra-salt deformation: An example from the Upper Permian Zechstein 3 stringer, western Dutch offshore
Authors: Strozyk F. , Van Gent H. , Urai J. L. , Kukla P. A.
Published: February 2012

Most of the information on subsurface evaporitic structures comes from 3D seismic data. However, this data only provide limited information about the internal structure of the evaporites, which is known from salt mines and salt diapir outcrops. Brittle intra-salt layers (carbonate, anhydrite, clay) of at least 10 m thickness form good reflectors in evaporites, but the structure and dynamics of such ‘stringers’ in the salt movement are poorly understood. In this study, we investigate the intra-salt Zechstein 3 (Z3) stringer from 3D seismic data in an area offshore the Netherlands. Observations show complex deformation including boudinage, folding and stacking. Reflections from thin and steep stringer parts are strongly reduced, and we present different structural models and tests of these. We compare our observations to structural models from salt mines and analogue/numerical models of intra-salt deformation. A smoothed representation of the upper surface of the stringer fragments follows the shape of Top Salt, but smaller-scale stringer geometries strongly differ from this and imply boudinage. The imaged disharmonic patterns of constrictional folds provide evidence for the complexity of the intra-salt, in agreement with observations in salt mines. This may be explained by interaction of the layered salt rheology, complex three-dimensional salt flow, different phases and styles of basement tectonics and movement of the overburden.
Salt-related structures on the Bristol Channel coast, Somerset (UK)
Authors: Trude James , Graham Rod , Pilcher Robin
Published: February 2012

This paper presents a new interpretation of well-known outcrops on the south coast of the Bristol Channel at Watchet in southern England. It is prompted by our recent experience of high-quality three-dimensional seismic datasets from areas such as the Gulf of Mexico and Brazil which are dominated by salt tectonics. Previous structural interpretations of the Watchet outcrops were explained in terms of extension, inversion and strike-slip tectonics. We suggest that some of the structures in the area are not easily explained by any of these mechanisms, but that they are collapse structures associated with salt withdrawal and imply salt diapirism during the Late Triassic and Early Jurassic.
Pre-existing salt structures and the folding of the Zagros Mountains
Authors: Callot Jean-Paul , Trocmé Vincent , Letouzey Jean , Albouy Emily , Jahani Salman , Sherkati Sharam
Published: February 2012

Four-dimensional analogue X-ray tomography imagery is used to investigate the role played by pre-existing salt structures during compressive deformation. Initially linear salt structures evolve towards more axisymmetric diapirs. Depending on the diapir geometry and on its thickness relative to the sedimentary column thickness, the diapirs are either (1) shortened and localize sharp overturned folds for vertical pipe-like diapirs or else (2) act as preferentially oriented ramps, the diapir being incorporated in the fold for pillow-like diapirs. The ridges have a strong effect on the lateral extent and orientation of folds: they disconnect the folds formed on either side of the salt wall. Compressional relays between ridges allow for a folded connection between both sides. The Zagros Mountains in southern Iran offer a large variety of comparable structures, associated with the Hormuz salt level which acts as the regional décollement. Most of the salt structures have been active from the Early Palaeozoic until the present day. The first-order critical taper is controlled by the distribution of Hormuz décollement level and by its thickness. At a smaller scale, the fold geometry and size are locally controlled by the pre-existing salt structures, which are the main source of heterogeneity in the deformation.
The Garmsar salt nappe and seasonal inversions of surrounding faults imaged by SAR interferometry, Northern Iran
Authors: Baikpour Shahram , Talbot Christopher J.
Published: February 2012

The allochthonous Tertiary salt of the Garmsar salt nappe extruded from where the most southerly point of the Alborz Mountain front is offset by the Zirab–Garmsar strike-slip fault. We used eleven descending Advanced Synthetic Aperture Radar (SAR) images, acquired by the European Space Agency's ENVISAT satellite from 2003 to 2006, to map surface displacement over 23 increments ranging in time from 30 to 2 months. A 30 month SAR interferogram of the area shows that the regional folds and faults are active south of the mountain front, but are dampened by the allochthonous salt that otherwise appears to be merely degrading at rates that vary with the season. Interferograms for shorter epochs display different patterns of fault blocks in the country rocks that rose and fell with the seasons. By relating surface displacements mapped in these interferograms to the contemporaneous seismic record, we find that seismic faults reactivate repeatedly while their kinematics may have inverted on remarkably short timescales. Seismic disturbances propagate very slowly and faults are longer than expected for earthquakes with ML<3.5, indicating that the regional strains are more aseismic than anticipated by earlier studies.
Submarine ‘salt glacier’ of Northern Tunisia, a case of Triassic salt mobility in North African Cretaceous passive margin
Authors: Masrouhi Amara , Koyi Hemin A.
Published: February 2012

Stratigraphical, sedimentological and structural data and a Bouguer gravity map of Medjez-El-Bab (MEB) in Northern Tunisia are used to illustrate a Cretaceous example of salt extrusion on a passive continental margin. Located just south of the Teboursouk thrust front (a preferential décollement surface used by the continuous Tertiary shortening in this area), the MEB structure is a simple N40°E box anticline. Removing the two Tertiary foldings (Eocene and Miocene) leads to the exposure of the original feature of a simple submarine ‘salt glacier’. The Triassic salt rocks appear as an Albian interstratified body between two Cretaceous series with stratigraphic normal polarity, suggesting a bedding parallel extrusion (at the sediment–water interface) of the Triassic salt in Cretaceous times. The formation of such salt extrusions are associated with extensional faulting (probably both in the cover and basement), the presence of a slope and basinwards salt flow. This scenario is similar to the allochthonous salt described in other salt provinces, characterizing passive margins.
Anatomy of an exposed vertical salt weld and flanking strata, La Popa Basin, Mexico
Authors: Rowan Mark G. , Lawton Timothy F. , Giles Katherine A.
Published: February 2012

La Popa Weld in La Popa Basin, Mexico, is a 24 km long near-vertical structure with a prominent bend approximately halfway along its length. Halokinetic folding, local unconformities and diapir-derived detritus in flanking strata document a precursor salt wall. Shortening during the latest Cretaceous to Eocene Hidalgoan Orogeny squeezed the salt wall to form the weld. Deformation varies significantly along the weld. The northwestern third has remnant gypsum (including a diapir at the northwestern end), little large-scale folding of flanking strata and only background fracture intensity. Directly NW of the bend are pods of gypsum linked by complete welds, a large-scale cuspate anticlinal geometry and significant fracturing within 5–10 m of the weld. The southeastern half is completely welded with no remnant gypsum, a prominent cuspate anticlinal geometry and a 50 m wide damage zone. The variable deformation was controlled by the original width of the salt wall and the amount and direction of shortening. Where orthogonal to the wall, shortening locally closed the diapir but little further deformation took place. Where oblique, shortening caused post-weld dextral strike-slip movement and significant fracturing and shearing of the wall rock. The resulting deformation variability likely impacted the sealing capability of the weld.
Allochthonous salt in the sub-Alpine fold–thrust belt of Haute Provence, France
Authors: Graham Rod , Jackson Martin , Pilcher Robin , Kilsdonk Bill
Published: February 2012

In the sub-Alpine chains of Haut Provence, SE France, a very well-exposed Mesozoic sequence showing rapid thickness and facies changes associated with Jurassic and Cretaceous extension on the margin of the Ligurian Tethys has been deformed by ‘Alpine’ compression which occurred from the Late Cretaceous to the Pliocene. Although the geology has been very well known for decades, aspects of the structure remain enigmatic and cannot be explained by either Mesozoic extension or Alpine shortening alone. We infer that some deformation resulted from salt tectonics. A completely overturned, highly condensed Jurassic section near Barles village resembles the elevated roof of a Triassic salt body in a deep-marine basin. This carapace became overturned as a flap in the Middle Jurassic when salt broke out at the seafloor and overran the inverted flap as an allochthonous extrusion, comparable to those in the deepwater Gulf of Mexico or Angola. Later, Alpine compression exploited the weakness of the salt sheet as the Digne Thrust moved over the inverted flap. Although the flap is in the footwall of the thrust, evidence of soft-sediment deformation and other anomalous structures within the flap suggest that it did not originate as an overturned footwall syncline.
Halokinetic-sequence stratigraphy, fluvial sedimentology and structural geometry of the Eocene Carroza Formation along La Popa salt weld, La Popa Basin, Mexico
Authors: Andrie Joseph R. , Giles Katherine A. , Lawton Timothy F. , Rowan Mark G.
Published: February 2012

The Eocene Carroza Formation in La Popa Basin, Mexico, represents fluvial sedimentation in a shortening-influenced salt-withdrawal minibasin, termed the Carroza Syncline. The Carroza Syncline lies adjacent to the La Popa salt weld, which was formerly a passively-rising salt wall that was shortened during the Hidalgoan Orogeny in Late Cretaceous and Palaeogene time. The Carroza Formation displays distinct upsection changes in fluvial facies distribution and geometry of halokinetic drape folding. Fluvial channel distribution changes upwards from widespread thin, broad channels with variable palaeocurrents in the lower part of the formation to thick, stacked channels concentrated in the hinge of the Carroza Syncline with weld-parallel palaeocurrent directions in the upper part. The upper and middle members of the Carroza contain debris-flow facies derived from diapir roof strata and the diapir itself. The style of halokinetic drape fold upturn and thinning towards the weld changes upsection from a broad (800–1500 m) to a narrow (50–200 m) zone, where upper Carroza strata are overturned and in direct contact with remnant gypsum along the weld. The upsection changes in fluvial facies distribution and geometry reflect an overall decrease in local sediment-accumulation rates relative to salt-rise rates controlled by both Hidalgoan shortening and passive diapirism.
Depositional and halokinetic-sequence stratigraphy of the Neoproterozoic Wonoka Formation adjacent to Patawarta allochthonous salt sheet, Central Flinders Ranges, South Australia
Authors: Kernen Rachelle A. , Giles Katherine A. , Rowan Mark G. , Lawton Timothy F. , Hearon Thomas E.
Published: February 2012

Parts of two third-order Neoproterozoic (Marinoan) depositional sequences are documented in the Wilpena Group (Wonoka Formation and Bonney Sandstone) at Patawarta diapir, located in the central Flinders Ranges, South Australia. These sequences represent an overall regressive succession transitioning upwards from outer to middle wave-dominated shelf deposits to a tidally dominated barrier bar to coastal plain. The lower, middle, upper limestone and green mudstone informal members of the Wonoka Formation comprise the Highstand Systems Tract of the lower sequence. The Sequence Boundary is at the top of the Wonoka green mudstone member and is overlain by the Lowstand Systems Tract of the upper sequence, which includes the lower dolomite, sandstone and upper dolomite beds of the Patsy Hill Member of the Bonney Sandstone. The upper sequence Transgressive Systems Tract comprises the Bonney Sandstone. These units comprise one complete tapered composite halokinetic sequence (CHS). The lower halokinetic-sequence boundary is associated with the Maximum Flooding Surface of the lower depositional sequence and the upper halokinetic-sequence boundary is interpreted as the Transgressive Surface of the overlying depositional sequence where an angular truncation of up to 90° is documented.
Salt: geology and tectonics of selected Brazilian basins in their global context
Authors: Mohriak Webster U. , Szatmari Peter , Anjos Sylvia
Published: February 2012

This work addresses the geological and geophysical interpretation of salt structures in selected Brazilian sedimentary basins, from intracratonic Palaeozoic evaporites in the Amazon and Solimões basins to divergent margin evaporite basins formed during the Mesozoic break-up of Gondwana. There is an intriguing correlation between evaporite basins and hydrocarbon accumulations in all the selected basins discussed. The Solimões and Amazonas basins developed evaporite depositing environments as the Middle Carboniferous sea was closing during a plate convergence phase. The salt basin along the eastern Brazilian and western African margins developed along the Mesozoic rifts of the South Atlantic. Regional seismic interpretation and potential field (gravity and magnetic) data over the eastern Brazilian and west African margins suggest a very thick autochthonous salt layer deposited over rifted continental crust and particularly above the thick sag basin sediments over the hyperextended crust that marks the transition from continental to oceanic crust. Most of the hydrocarbon discoveries in the eastern Brazilian and western African margins are in post-salt turbidite and carbonate reservoirs, but recent discoveries in the deepwater salt basins along the southeastern Brazilian margin indicate that pre-salt plays will represent an important contribution to hydrocarbon production in the near future.
Perceptions and Experiences of Women in Karachi, Pakistan Regarding Secondary Infertility: Results from a Community-Based Qualitative Study
Authors: Sami Neelofar , Saeed Ali Tazeen
Published: February 2012

Background. The prevalence of infertility in Pakistan is 22% with primary infertility at 4% and secondary infertility at 18%. This study explored perceptions and experiences of women in Karachi, Pakistan regarding the causes, treatment-seeking behavior for and consequences of secondary infertility.Methods. Focus group discussions and in-depth interviews with married women explored their perceptions and experiences for issues related to secondary infertility.Results. The knowledge of women about the causes and scientific treatment options for infertility was limited resulting in inclination for traditional unsafe health care. Infertility was stated to result in marital instability, stigmatization and abuse specially for women with no live child.Conclusions. Since infertility can have a serious effect on both the psychological well-being and the social status of women in Pakistan, effective interventions are the need of the day. There is a dire need for health education and counseling to be integrated into infertility management plans.