Fold Growth Research Articles

Sedimentary and structural evolution of a Pleistocene small-scale push moraine in eastern Poland: New insight into paleoenvironmental conditions at the margin of an advancing ice lobe

Abstract Recent studies of push moraines have focused on the interplay between the dynamics of ice margins and the environmental variables of the foreland into which they advance. These studies showed that the spatial distribution, geometry and style of the glaciotectonic deformation of push moraines are controlled by ice-induced stresses, the strain rate, the rheology of the deposits and hydraulic conductivity. In this work, we provide new insight into this interplay at a small spatio-temporal scale, specifically, the ancient glacial system of the Liwiec ice lobe within the younger Saalian ice sheet in eastern Poland. The paleoenvironmental variables that are analysed here refer to the dynamics of the hydrological processes that affected the patterns and sediment deposition rate on the terminoglacial fan and the resulting mechanical stratigraphy and hydraulic conductivity of the foreland. We document the progradational sequence of the fan deposits that developed as a result of the ice lobe thickening and the steepening of its stationary front. The sedimentary features of the fan, the lithology of its basement and the hydraulic conductivity of the foreland strongly influenced the geometry and kinematics of fold growth during the advance of the ice lobe. The predominance of flexural slip and the development of fractures, including fold-accommodation faults, were interpreted to be an effect of buckle folding due to horizontal shortening induced by ice advance. The partial overriding of the push moraine by the ice lobe and, thus, the submarginal conditions for deformation were inferred from the significant hinge migration and internal deformation of the strata under undrained conditions in one of the folds. The synfolding deposition pattern of the fan growth strata allowed us to suggest that the push moraine was probably formed by a sustained advance rather than surge.

Crestal graben fluid evolution during growth of the Puig-reig anticline (South Pyrenean fold and thrust belt)

The Puig-reig anticline, located in the South Pyrenean fold and thrust belt, developed during the Alpine compression, which affected the upper Eocene-lower Oligocene sediments of the Solsona and Berga Formations. In this study, we highlight the controls on formation of joints and reverse, strike-slip and normal faults developed in the crest domain of the Puig-reig anticline as well as the relationships between fluids and these fractures. We integrated structural, petrographic and geochemical studies, using for the first time in the SE Pyrenees the clumped isotopes thermometry to obtain reliable temperatures of calcite precipitation.Structural and microstructural analysis demonstrate that at outcrop scale fracturing was controlled by rigidity contrasts between layers, diagenesis and structural position within the anticline, whereas grain size, cementation and porosity controlled deformation at the microscopic scale. Petrographic and geochemical studies of calcite precipitated in host rock porosity and fault planes reveal the presence of two migrating fluids, which represents two different stages of evolution of the Puig-reig anticline. During the layer-parallel shortening, hydrothermal fluids with temperatures between 92 and 130°C circulated through the main thrusts to the permeable host rocks, reverse and most of strike-slip faults precipitating as cement Cc1. During the fold growth, meteoric waters circulated downwards through normal and some strike-slip faults and mixed at depth with the previous hydrothermal fluid, precipitating as cement Cc2 at temperatures between 77 and 93°C.Integration of the results from the Puig-reig anticline in this work and the El Guix anticline indicates that hydrothermal fluids did not reach the El Guix anticline, in which only meteoric and evolved meteoric waters circulated along the fold.

Campanian Paleoseismites of the Elk Basin Anticline, Northern Bighorn Basin, U.S.A.: A Record of Initial Laramide Deformation

Abstract Paleoseismites, in the form of clastic dikes and sills and convolute bedding record syndepositional tectonism prior to lithification, fold growth, and onset of major orogenic events. The Elk Basin anticline, located in the northern portion of the Bighorn Basin, contains paleoseismites in Campanian strata along its eastern (forelimb) and western (back limb) margins. In the shallow-marine Telegraph Creek and Claggett formations, convolute bedding typically involves individual sandstone beds with vertical to overturned strata on either side of a nearly vertical vent, whereas the nonmarine Eagle Formation contains planar clastic dikes and sills, derived from liquefied sand-source beds, and convoluted bedding involving distorted laminae. Planar clastic dikes and sills were injected upward and laterally across overlying strata, and along pre-existing, nearly vertical, near-surface joints. Geographically, clastic dikes and sills are present only in the central portion of the anticline, while convoluted-bedding is present in the central and southern portions. Comparison of 145 clastic-dike measurements with 61 previously reported Laramide joint-set orientations for the Elk Basin demonstrate trends to be similar. Clastic dikes preferentially fill cross joints oriented normal to the axial trace of the anticline, while strike joints illustrate a dominant later Laramide joint set oriented subparallel to the axial trace. Paleoseismite formation is consistent with ∼ M 5.5 earthquakes during earliest Laramide deformation associated with development of the Elk Basin thrust fault, whereas strike joints formed during subsequent Laramide deformation after burial and cementation of Campanian strata.

Modeling of wind gap formation and development of sedimentary basins during fold growth: application to the Zagros Fold Belt, Iran

AbstractMountain building and landscape evolution are controlled by interactions between river dynamics and tectonic forces. Such interactions have been extensively studied, however a quantitative evaluation of tectonic/geomorphic feedbacks, which is imperative for understanding sediments routing within orogens and fold‐and‐thrust belts, remains to be undertaken. Here, we employ numerical simulations to assess the conditions of uplift and river incision necessary to deflect an antecedent drainage network during the growth of one, or several, folds. We propose that a partitioning of the river network into internal (endorheic) and longitudinal drainage arises as a result of lithological differences within the deforming crustal sedimentary cover. Using examples from the Zagros Fold Belt (ZFB), we show that drainage patterns can be linked to the non‐dimensional incision ratio R between successive lithological layers, corresponding to the ratio between their relative erodibilities or incision coefficients. Transverse drainage networks develop for uplift rates smaller than 0.8 mm yr−1 and low incision ratios (−10 < R < 10). Intermediate drainage networks are obtained for uplift rates up to 2 mm yr−1 and large incision ratios (R > 20). Parallel drainage networks and the formation of sedimentary basins occur for large values of incision ratio (R > 20) and uplift rates between 1 and 2 mm yr−1. These results have implications for predicting the distribution of sediment depocenters in fold‐and‐thrust belts, which can be of direct economic interest for hydrocarbon exploration. They also put better constraints on the fluvial and geomorphic responses to fold growth induced by crustal‐scale tectonics. Copyright © 2016 John Wiley & Sons, Ltd.

3D fold growth in transpression

Geological folds in transpression are inherently 3D structures; hence their growth and rotation behavior is studied using 3D numerical finite-element simulations. Upright single-layer buckle folds in Newtonian materials are considered, which grow from an initial point-like perturbation due to a combination of in-plane shortening and shearing (i.e., transpression). The resulting fold growth exhibits three components: (1) fold amplification (vertical), (2) fold elongation (parallel to fold axis), and (3) sequential fold growth (perpendicular to axial plane) of new anti- and synforms adjacent to the initial fold. Generally, the fold growth rates are smaller for shearing-dominated than for shortening-dominated transpression. In spite of the growth rate, the folding behavior is very similar for the different convergence angles. The two lateral directions always exhibit similar growth rates implying that the bulk fold structure occupies an increasing roughly circular area. Fold axes are always parallel to the major horizontal principal strain axis (λ→max, i.e., long axis of the horizontal finite strain ellipse), which is initially also parallel to the major horizontal instantaneous stretching axis (ISA→max). After initiation, the fold axes rotate together with λ→max. Sequential folds appearing later do not initiate parallel to ISA→max, but parallel to λ→max, i.e. parallel to the already existing folds, and also rotate with λ→max. Therefore, fold axes do not correspond to passive material lines and hinge migration takes place as a consequence. The fold axis orientation parallel to λ→max is independent of convergence angle and viscosity ratio. Therefore, a triangular relationship between convergence angle, amount of shortening, and fold axis orientation exists. If two of these values are known, the third can be determined. This relationship is applied to the Zagros fold-and-thrust-belt to estimate the degree of strain partitioning between the Simply Folded Belt and the bordering strike-slip fault-system.

Landward migration of active folding based on topographic development of folds along the eastern margin of the Japan Sea, northeast Japan

The eastern margin of the Japan Sea, northeast Japan, lies in a strongly compressional area, and contractional deformation in the region is ongoing. We reconstructed the temporal and spatial evolution of contractional deformation across the Tohoku district on the eastern margin of the Japan Sea, by using surface geologic and geomorphologic data. We measured the distance from the fold hinge to the topographic ridge line in antiforms, developed by surface uplift, associated with fold growth under the E–W to WNW–ESE compressional stress regime. The topographic development of fold structures, developed in the region since the Pliocene, is consistent with the activity of the folds. When the folding that generates the uplift becomes inactive, the topographic contrasts between hinge and ridge location can be remarkable. Spatial variations in this parameter are consistent with the systematic eastward migration of fold growth in the area. The documentation of fold-related topography thus provides important information for understanding the dynamics of folding along the eastern margin of the Japan Sea.

Induction of Resistance to Proteasome Inhibition Preferentially Switches Survival Dependence from Bcl-2 to XIAP in Preclinical Models of Waldenstrom Macroglobulinemia: Pre-Clinical Rationale for Early Clinical Sequencing of ABT199

Background: The proteasome is an established and druggable target for the treatment of plasma cell-related malignancies including Waldenstrom macroglobulinemia (WM). WM cells as a consequence of high immunoglobulin production and increased B-cell receptor (BCR) mediated proliferation upregulate proteasome activity. Additionally, microenvironmental influence mediated through BCR signaling directly influences Bcl-2 and its BH3 family members, supporting tumor cell survival. Indeed, WM patients derive significant clinical benefit from proteasome-inhibitor (PI) based therapy with agents such as bortezomib and carfilzomib. However, resistance to PI develops over time and for these patients the optimal choice and sequence of therapy has yet to be determined. Using our WM models of PI-resistance we interrogated molecular events within the BCR and Bcl-2 pathways to determine therapeutic potential of targeting these crucial pathway in PI-resistance.Materials & Methods: WM cell lines (BCWM.1 and MWCL-1) and carfilzomib-resistant (CR) subclones (BCWM.1/CR and MWCL-1/CR) were used in experiments. Gene-expression and long-noncoding (LNC) RNA analysis was performed (Arraystar) and validated by real-time PCR. Bortezomib, carfilzomib, ABT199 and ibrutinib were purchased from Sellekchem.Results: To determine the functional impact of BCR and Bcl-2 signaling in PI-resistance, as well as therapeutic sensitivity of PI-resistant cells to their inhibitors (ibrutinib, ABT-199, respectively), we established and characterized WM cell lines resistant to carfilzomib. BCWM.1/CR cells showed approximately 20-fold resistance to carfilzomib (IC50 = 92.75nM) and MWCL-1/CR cells approximately 10-fold resistance (Fig. 1A). Both CR clones also displayed some cross-resistance to bortezomib. Gene expression and LNC-RNA profiling demonstrated several changes between carfilzomib-resistant vs. sensitive WM cells. Analysis of proteasome-related mRNA revealed downregulation of PSMB5, PSMB1, PSMB2 and PSMB8. Similarly, profiling of BCR-associated genes demonstrated decreased expression of several components, including BTK and SPI1. This observation functionally manifested as reduced sensitivity to the BTK-inhibitor ibrutinib, wherein CR cells displayed 1.5 - 2 fold growth resistance to ibrutinib on 72hr MTS assay. Next we examined the expression of Bcl-2 family members in CR cells. Intriguingly, we observed that Bcl-2 and Mcl-1 were significantly downregulated but XIAP (inhibitor of apoptosis) was significantly increased in CR cells vs. wildtype WM cells- both at transcriptional and translational levels. This suggested that upon acquisition of CR, a transcriptional shift towards XIAP occurs to accommodate sustained therapeutic stress from carfilzomib and maintain steady antiapoptotic composure. To test if the PI-resistant cells have moved away from their survival dependence on Bcl-2, we treated CR cells to increasing concentrations of the Bcl-2-specific inhibitor, ABT199, and as anticipated, CR cells displayed reduced apoptosis in presence of ABT199 compared to wildtype WM cells (32% annexin-V staining vs. 50%, respectively) (Fig. 1B).Conclusions: Our study sheds insight into the differential drivers of PI-resistance particularly towards carfilzomib, in WM cells. We demonstrate that acquisition of CR is associated with downregulation of Bcl-2 and Mcl-1, which is countered by upregulation of XIAP- an event that renders CR cells resistant to ABT199 (as it targets only Bcl-2). Likewise, downregulation of BCR-related components in CR cells was associated with reduced sensitivity towards ibrutinib. These observations suggest that acquisition of resistance to PI such as carfilzomib can impact future treatment with agents such as ibrutinib or ABT199. Our preclinical models provide rationale or early sequencing of ibrutinib or ABT199 in therapeutic planning of WM patients prior to induction of PI resistance. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

The Devil truly is in the detail. A cautionary note on computational determinism: Implications for structural geology numerical codes and interpretation of their results

The widespread use of numerical modeling codes in structural geology, particularly in forward modeling of crustal deformation, has brought valuable insight into many processes such as fault initiation and propagation, fold growth, and orogenic wedge development. Whether commercial, open source, or the result of an individual researcher’s endeavor, such numerical codes increasingly rely on advanced compiler optimizations and/or parallelization techniques. This is done to maximize performance on today’s multicore processors and thus achieve tractable model runtimes. However, such speed and productivity can come at a price. Many optimization and parallelization techniques used do indeed produce remarkable runtime speedups, but at the expense of determinism and reproducibility. Most researchers are only tangentially aware of these issues. I have aimed to explain why numerical model runs with identical sets of initial and boundary conditions can potentially produce different results and thus, sensu stricto, be nondeterministic. I have developed some solutions and guidelines for maintaining determinism and evaluated these issues using a discrete element code of upper crustal deformation. Implications for the interpretation and use of such model results in structural geology were also evaluated.

The interplay between deformation, erosion and sedimentation in the deep‐water Mexican Ridges foldbelt, western Gulf of Mexico basin

AbstractWe analyse a regional 2D seismic section of the Mexican Ridges foldbelt (MRFB), western Gulf of Mexico, and construct excess‐area diagrams for each of the structures comprising the foldbelt to estimate shortening, the onset of folding and the degradation of the folded seafloor. From the chronostratigraphy, we derive rates of tectonic and superficial mass transport and illustrate how they change across the MRFB. The resulting tectonic transport in the MRFB is 11.8 km forming a train of twelve buckle folds above a detachment at a depth of ca. 6 s of two‐way travel time, with an average strain of ca. 10%. The fold train grew at a mean uplift rate of ca. 0.21 mm year−1. Cross‐sectional balancing demonstrates that shortening balances the down‐slip motion of the Quetzalcoatl extensional system (QES), suggesting that horizontal compaction, volume loss and other penetrative deformation mechanisms are negligible. By assuming steady‐state denudation, we are able to distinguish sediments derived locally from sediments transported from distant sources. The constant of mass diffusivity, a parameter controlling the degradation rate, is ca. 0.42 m2 year −1, which is characteristic of rapid, episodic, superficial mass movements. The combined sedimentation rate from both, local and distal sources is ca. 0.23 mm year −1. Those values are not constant; structures proximal to the continental shelf are rising rapidly and are being degraded more intensely than those in the distal part of the MRFB, where sedimentation outweighs tectonic uplift. Our results indicate deformation initiated up to 3 Myr earlier than estimated from stacking patterns. Moreover, we find deformation started synchronously during the Late Miocene throughout the MRFB and not in two episodes as the stacking relations suggest. The discrepancy can be explained by a delay in the sedimentary response to folding. During early fold growth, nearly constant thickness strata are deposited before a progressive unconformity and other converging geometries develop. The development of growth strata is fast in the folds near the QES, which are being uplifted rapidly and degraded vigorously. Under these conditions, the stratigraphic relations give only a broad estimate of the pretectonic/syntectonic limit when compared to the excess‐area method. On the other hand, the development of growth strata took twice as much time for folds near the abyssal plain, which are being uplifted at a slower rate and where degradation is less intense. Consequently, the delay takes more time, and the use of stratigraphic relations introduces an even more pronounced bias towards younger ages in the identification of the onset of folding.

Growth-Phase-Specific Modulation of Cell Morphology and Gene Expression by an Archaeal Histone Protein.

ABSTRACTIn all three domains of life, organisms use nonspecific DNA-binding proteins to compact and organize the genome as well as to regulate transcription on a global scale. Histone is the primary eukaryotic nucleoprotein, and its evolutionary roots can be traced to the archaea. However, not all archaea use this protein as the primary DNA-packaging component, raising questions regarding the role of histones in archaeal chromatin function. Here, quantitative phenotyping, transcriptomic, and proteomic assays were performed on deletion and overexpression mutants of the sole histone protein of the hypersaline-adapted haloarchaeal model organism Halobacterium salinarum. This protein is highly conserved among all sequenced haloarchaeal species and maintains hallmark residues required for eukaryotic histone functions. Surprisingly, despite this conservation at the sequence level, unlike in other archaea or eukaryotes, H. salinarum histone is required to regulate cell shape but is not necessary for survival. Genome-wide expression changes in histone deletion strains were global, significant but subtle in terms of fold change, bidirectional, and growth phase dependent. Mass spectrometric proteomic identification of proteins from chromatin enrichments yielded levels of histone and putative nucleoid-associated proteins similar to those of transcription factors, consistent with an open and transcriptionally active genome. Taken together, these data suggest that histone in H. salinarum plays a minor role in DNA compaction but important roles in growth-phase-dependent gene expression and regulation of cell shape. Histone function in haloarchaea more closely resembles a regulator of gene expression than a chromatin-organizing protein like canonical eukaryotic histone.

Influence of surface processes and initial topography on lateral fold growth and fold linkage mode

Elongation of randomly distributed fold segments and their potential linkage are important for hydrocarbon exploration because it can greatly influence the morphology of the reservoir and both migration and accumulation of hydrocarbons in antiformal traps. Here we study the effects of surface processes and the presence of a topographic slope on the different linkage modes that can occur, and how these parameters affect the required horizontal offset for perturbations to link. The proposed numerical model represents a sedimentary cover detached over a much weaker basal decollement layer. The upper surface is modified by mass redistribution, which is achieved by a combination of fluvial and hillslope processes. Several series of simulations were performed: (1) without surface processes or regional slope, (2) with regional slope only, (3) with fluvial incision and hillslope processes, and (4) with hillslope processes only. Model results show that the presence of a regional slope reduces the critical distance required for the transition between linkage and no linkage modes, whereas erosion and redeposition of sediments, on the contrary, increase this distance. The location of the saddle point, where fold segments link, and its vertical distance to the crests of the anticlines are different compared to the case without erosion or initial topographic slope, which potentially can affect the morphology of hydrocarbon traps. Moreover, both erosion and redeposition of sediments enhance the fold elongation (growth along the fold axis), once the erosion velocity exceeds the folding velocity. Model results have been compared to the Zagros Fold Belt.

3D geometry of a shale-cored anticline in the western South Caspian Basin (offshore Azerbaijan)

The internal structure of one of the common fold structures in the western margin of the South Caspian Basin (SCB) has been characterized in 3D using a depth-migrated seismic cube in offshore Azerbaijan. The fold corresponds to a NNW-SSE anticline with a basinward vergence; i.e., eastwards, because in this direction of the margin the SCB is floored by a probable oceanic crust. The anticline has two culminations cut by mud-diapirs and is bounded by two parallel rim synclines with contrasting sedimentary thickness. This anticline deforms congruently the thick Productive Series (PS; Messinian to Late Pliocene), whereas the most recent sequences (<3.1 Ma; e.g., Akchagyl and Apsheron units) onlap or thin towards the fold crest.We reconstruct the existence of two episodes of folding. During deposition of the uppermost PS sequences (ca. 3.5–3.4 to 3.1 Ma), fold uplift initiated with a significantly lower rate than sedimentation. During this epoch, folding was accompanied by basin tilting and by faulting in a basinward normal fault with a limited right lateral, strike-slip component. Motion along this fault zone promoted the downdip flow of a weak layer formed by fluid- and mud-rich sediments (Maykop Formation), which also migrated along strike to build-up the growing anticline. Henceforth, fold growth accelerated and sedimentary units like the Akchagyl (3.1–1.7 Ma) were deposited preferentially in the subsiding flanks. Seafloor upwarping due to folding conditioned the sediment transport, and large deltas adapted their prograding pattern to the growing anticline crest.This structure resembles a detachment fold with a leading, East-vergent forelimb. Nevertheless, the occurrence of progressive tilting accompanying sedimentation and folding, or the mud inflation of the fold core by deep flow parallel to the anticline axis, make this example in the SCB a special example of this fold type.

Active flexural‐slip faulting: A study from the Pamir‐Tian Shan convergent zone, NW China

AbstractThe flexural‐slip fault (FSF), a type of secondary fault generated by bed‐parallel slip, occurs commonly and plays an important role in accommodating fold growth. Although the kinematics and mechanics of FSFs are well studied, relatively few field observations or geometric models explore its geomorphic expression. In the Pamir‐Tian Shan convergent zone, NW China, suites of well‐preserved FSF scarps displace fluvial terraces in the Mingyaole and Wulagen folds. Integrating interpretations of Google Earth images, detailed geologic and geomorphic mapping, and differential GPS measurements of terrace surfaces, we summarize geomorphic features that typify these faults and create kinematic models of active flexural‐slip faulting. Our study indicates the following: (i) FSF scarps commonly occur near synclinal hinges, irrespective of whether (a) the dip direction of beds on either side of the hinge is unidirectional or in opposite directions, (b) the hinge is migrating or fixed, or (c) the hinge shape is narrow and angular or wide and curved. (ii) Active FSFs are likely to produce higher scarps on steeper beds, whereas lower or no topographic scarps typify gentler beds. (iii) Tilt angles of the terrace surface displaced above FSFs progressively decrease farther away from the hinge, with abrupt changes in slope coinciding with FSF scarps; the changes in tilt angle and scarp height have a predictable geometric relationship. (iv) Active FSFs can accommodate a significant fraction of total slip and play a significant role in folding deformation. (v) Active FSFs may be used to assess seismic hazards associated with active folds and associated blind thrusts.

Clonal Growth Capacity and Phenotype of Ex Vivo Expanded Oral Mucosal Tissue

PurposeCultured oral mucosal epithelial cells can treat stem cell deficiency of the cornea. The present study aims to determine the best site for harvesting oral mucosal cells and the effects of four media on these cultured cells.MethodsPieces of oral epithelium were used from four locations: buccal mucosa (BM), hard palate (HP), lower lip (LL), and transition zone of the lower lip (TZ) of Sprague‐Dawley rats. Explants were grown in four different culture media for six days. The media were 1) RPMI 1640; 2) EpiLife; 3) oral keratinocyte medium (OKM); and 4) DMEM and Ham 12 (1:1 mixture). Morphology, phenotype, and colony forming efficiency were analyzed.ResultsDMEM and RPMI yielded higher explant outgrowth than OKM and EpiLife. Using DMEM and RPMI, fold growth was superior from LL biopsies (36.43 ± 7.42 and 32.34 ± 12.22, respectively) compared to biopsies from HP (7.46 ± 0.69 and 10.14 ± 1.14, respectively), BM (11.15 ± 2.94 and 22.40 ± 8.45, respectively) and TZ (19 ± 3 and 15 ± 4.02, respectively) (p&lt;0.05; N=4‐11). The percentage of PCNA+ cells was lower near the explant than at the leading edge whereas the percentage of NGF P75+ was not significantly different in any of the locations. In DMEM, cells from TZ showed higher colony forming efficiency (0.059% ± 0.004%) than cells from BM, HP and LP (p&lt;0.05; N=5).ConclusionsThe transition zone of the lower lip, which showed the highest colony forming ability, may be most effective in treating limbal stem cell deficiency.

Mechanism of Plant Growth Promoting Activity of Burkholderia Species

Application of plant growth promoting rhizobacteria (PGPR) to boost up production and reduce pathogenesis is an imminent approach in agriculture. One of the PGPR (RR18) was found to have best plant growth promoting characteristics among 41 PGPR shortlisted from the 162 bacteria isolated from the groundnut rhizosphere. RR18 reduced disease incidence and increased germination of groundnut seeds in presence of A. niger. RR18 was found to induce systemic resistance in A. hypogaea L. as it induced chitinase, ß – 1,3- glucanase, phenylalanine ammonia lyase, peroxidase, polyphenol oxidase, lipoxygenase and jasmonic acid. Investigation of the specific mechanism by a comparative 2D gel electrophoresis of bacteria treated and untreated groundnut seedlings revealed induction of several proteins, two of them very prominently seen were- 60 kD and 56 kD proteins. These proteins were identified as Phospho-2-dehydro-3-deoxyheptonate aldolase 1 and auxilin related protein 1 using MALDI TOF and Mascot analysis. Phospho-2-dehydro-3-deoxyheptonate aldolase 1 is reported to synthesize secondary metabolites derived from intermediates of the pre-chorismate pathway up to shikimate. Auxilin related protein 1 belongs to DnaJ protein family and reported to be involved in protein folding, protein transport and plant growth promoting activity. 16S rDNA sequence of RR18 showed 99 % homology to Burkholderia species.

Syndepositional forced folding and related fluid plumbing above a magmatic laccolith: Insights from outcrop (Lower Cretaceous, Basque-Cantabrian Basin, western Pyrenees)

Emplacement of shallow magmatic laccoliths can result in the development of dome-shaped forced folds and fractures in the overburden and at the depositional surface. These folds and fractures have been described from both outcrop studies and seismic interpretation; however, the main controls on fold growth and fracture development remain unclear and, in some cases, controversial. This paper presents a new approach in the analysis of the growth of laccolith intrusions and forced folds. In this study, deep-water growth deposits at an outcrop in the Basque-Cantabrian Basin (north Iberia) record the coeval formation and evolution of a late Albian forced fold and related clastic dike system above the igneous Larragan laccolith. The vertical succession allows field mapping and characterization of the growth deposits, the underlying forced fold, and the forcible Larragan laccolith at depth. The Larragan laccolith is 600 m wide and 40 m thick and intrudes an organic-rich unit at an original (decompacted) depth of ∼450 m. A multidisciplinary study (sedimentology, structure, petrology, and geochemistry) of the growth deposits reveals that the emplacement of the laccolith created a dome-shaped upward-widening fold, which had a final relief of 18–36 m and a width of ∼850 m at the paleoseabed. Simultaneously, in the hinge zone of the fold, local tensional stress induced the formation of a fracture system, which subsequently acted as conduits for overpressured ascending fluids (methane and water) and fluidized sediments originating from the metamorphic aureole of the laccolith. This plumbing system reached the paleoseabed, where extruded sediments were deposited and methane-derived carbonates precipitated. A comprehensive model is proposed in which incremental emplacement of magma sheets induced pulsating contact metamorphism, folding and fracturing of the overburden, and episodic activity of the fluid plumbing system.

The low male voice is a costly signal of phenotypic quality among Bolivian adolescents

The human voice is one of the most conspicuous and dimorphic human secondary sexual characteristics; males' low fundamental and formant frequencies barely overlap with females'. Researchers often assert that low male voices are costly signals of phenotypic quality; however, no evidence currently exists linking low voices with indicators of quality (i.e., health or physical condition) during the ages where the larynx develops to adult proportions. In the present study, we examine the relationships between condition, testosterone, and vocal parameters in 91 Bolivian peri-pubertal adolescent males. Condition is operationalized as immune function (based on secretory IgA) and energetic reserves (BMI-for-age residuals from Tsimane-specific growth curves, and body fat percentage), and “masculine” vocal parameters is operationalized as having low fundamental frequency, narrow formant position, and low fundamental-frequency variation. We target peri-pubertal individuals to capture variation in vocal parameters during the canalization period for vocal fold and vocal tract growth. Results indicate that males in better energetic condition have higher testosterone levels and lower voices, controlling for age. Further, testosterone mediates the relationship between condition and a lower voice (i.e., lower fundamental and formant frequencies). We suggest that testosterone plays a key mediating role in the causal pathway linking phenotypic condition to a “masculine” voice. Our results provide support for a costly-signal model of low men's voices.

Laryngeal pathology at school age following very preterm birth

IntroductionIntubation injury resulting in laryngeal pathology is recognised as a possible complication of preterm birth, yet few published studies have examined such pathology and its relation to voice outcomes. This study reports on the results of prospective laryngeal function examinations of a cohort of very preterm children, all of whom presented with significant dysphonia at school age. Materials and methodsThe laryngeal pathology of 20 very preterm children, born between 23 and 29 weeks gestation, was examined under halogen and stroboscopic conditions. Laryngeal structure and function were assessed using a rigid laryngoscope or a flexible nasendoscope. The approach was selected based on the age and/or likely compliance of the child. ResultsNineteen children were found to have structural laryngeal pathology. Fourteen children presented with a chink to the posterior glottis and all demonstrated at least a mild degree of supraglottic hyperfunction. Other common findings were arytenoid prolapse and vocal fold immobility. More isolated findings included posterior scar band, vocal fold atrophy, arytenoid oedema and growth on the vocal folds. One child who presented with structural laryngeal pathology was never intubated. DiscussionSupraglottic hyperfunction was common to all participants, regardless of the nature and extent of underlying structural laryngeal pathology. Posterior glottic chink was the most common pattern of incomplete vocal fold closure. These data support the hypothesis that very preterm children adopt supraglottic tightening to compensate for underlying laryngeal pathology. The mechanism underlying laryngeal damage in the child who was not intubated is unclear. ConclusionsVoice quality of very preterm children is affected by both laryngeal structure and function. A trial of behavioural voice treatment is recommended to evaluate any therapeutic response in this population.

Histological changes in vocal fold growth and aging.

Sophisticated descriptions of the highly specialized vocal fold microarchitecture have been available for over three decades, but how this anatomy evolves with growth and aging remains an area of active investigation and, at times, a source of controversy. As our aging population expands and interest in pediatric voice disorders blossoms, it is timely to consider our contemporary understanding of evolving vocal fold histology and its implications for voice production. Novel applications of existing and emerging biotechnology, development of animal models and skillful use of human specimens have afforded greater insights into the histologic vocal fold changes seen throughout the lifespan in health and disease. Burgeoning knowledge has laid the foundation for more comprehensive models of vocal fold histology and has led to the development of innovative therapies for challenging voice disorders.

Preparation and properties of nanodiamond/poly(lactic acid) composite nanofiber scaffolds

Nanodiamonds (NDs) were employed for the first time to enhance the mechanical properties of poly(lactic acid) (PLA)-based nanofiber scaffolds. Uniform ND/PLA composite nanofibers can be electrospun at <1 wt% loading of NDs. The introduction of NDs improved the thermal stability of PLA-based nanofibers. Fourier transform infrared spectroscopy results demonstrated good adhesion between ND nanofillers and PLA matrix. Following the addition of NDs, the four mechanical indicators, tensile strength, Young’s modulus, elongation at break and fracture toughness of ND/PLA composite nanofiber membranes increased accompanied by the later decrease with the rise of ND content. The four indicators achieved their respective maximum value at 1 wt% ND content, which revealed 2.4 fold increase of tensile strength, 1.6 fold augment of Young’s modulus, 1.4 fold elevation of elongation at break, and 4.8 fold growth of fracture toughness, respectively. Compared with the tensile strength and Young’s modulus of neat PLA, ND nanofillers exhibited the best reinforcing ability for PLA-based composite nanofibers, which was attributed to the effective interfacial adhesion between PLA and rigid ND particles and the good dispersion of NDs in PLA matrix. The ND/PLA composite nanofiber membranes with improved mechanical properties possess potential application in biomedical engineering.