The terms mélange and broken formation have been used in different ways in the literature. The lack of agreement on their definition often leads to confusion and misinterpretations. An evaluation of ...the various uses of these terms allows us to consider several types of chaotic rock bodies originated by tectonic, sedimentary and diapiric processes in different tectonic settings. Our review of stratal disruption and mixing processes shows that there exists a continuum of deformation structures and processes in the generation of mélanges and broken formations. This continuum is directly controlled by the increase of the degree of consolidation with burial. In tectonically active environments, at the shallow structural levels, the occurrence of poorly consolidated sediments favors gravitational deformation. At deeper structural levels, the deformation related to tectonic forces becomes gradually more significant with depth. Sedimentary (and diapiric) mélanges and broken formations represent the products of punctuated stratal disruption mechanisms recording the instantaneous physical conditions in the geological environment at the time of their formation. The different kinematics, the composition and lithification degree of sediments, the geometry and morphology of the basins, and the mode of failure propagation control the transition between different types of mass-transported chaotic bodies, the style of stratal disruption, and the amount of rock mixing. Tectonically broken formations and mélanges record a continuum of deformation that occurs through time and different degrees of lithification during a progressive increase of the degree of consolidation and of the diagenetic and metamorphic mineral transformation. Systematic documentation of the mechanisms and processes of the formation of different broken formations and mélanges and their interplay in time and space are highly important to increase the understanding of the evolutionary history of accretionary wedges and orogenic belts.
►Re-evaluation of the definitions of the terms mélange and broken formation. ►Tectonic, sedimentary and diapiric mélanges in different tectonic settings. ►Mechanisms and processes of stratal disruption and mixing.
The Paleogene carbonate “megabreccia” units of the Friuli Basin are composite deposits produced by catastrophic shallow-water carbonate platform collapses re-deposited in relatively deep-water inner ...foredeep settings developed at the front of the advancing Dinaric thrust system. These thick, basin-wide mass transport deposits (MTDs) record the catastrophic emplacement of bipartite slide masses, comprising a lower coherent/cohesive blocky flow and an upper grain/turbulent flow. We here present the results of micro- to outcrop-scale structural analyses, constrained by stratigraphic and sedimentologic observations, performed to identify the internal deformation mechanisms and the emplacement processes of four of the largest MTDs exposed in two large three-dimensional outcrops: the Vernasso (NE Italy) and Anhovo (W Slovenia) open-pit quarries. Our results reveal a variety of primary (sedimentary) soft sediment deformation structures testifying fluid overpressure conditions within the brecciated, fine-grained matrix that sustain, intrude and surround slide blocks and clasts. Meso-scale structural analyses unraveled paleo-transport directions toward the N for the Vernasso quarry and toward the S for the Anhovo quarry. This suggests a forced propagation of the mass transport events controlled by the shape of basin, and reinforces the interpretation of different source areas related to multiple collapses from a carbonate platform rimming the southeastern tip of the basin. These units are thought to represent exhumed fossil examples of the MTDs extensively mapped in the present-day, carbonate-dominated continental margins, and thus, considered as reliable analogues for integrated studies.
•Vertical slide body partition into basal cohesive and upper turbulent flows•Basal subdivision into lower visco-fluid and upper visco-plastic parts•Supporting sedimentary matrix with fluid overpressure-related liquefaction•Slope gradient breaks leading to deformation and erosion of the substrate•Different source areas and paleo-transport direction for the main MTDs
We present the integrated outcrop-geophysical study of two mass transport complexes, the exhumed Specchio unit in the Northern Apennines of Italy and the Holocene Poverty unit in the Hikurangi margin ...of New Zealand. The combination of micro- to meso-scale structural, stratigraphic and sedimentologic analyses carried on continuous three-dimensional outcrops, with large-scale structural and morphologic data deriving from seismic/acoustic imaging of the present-day continental margins, allow important considerations on submarine landslide processes and mechanisms through the broader (up-scaled and down-scaled) understanding of the mass transport-related structural associations. We compare the discontinuous high-amplitude, reverse-polarity reflectors observed within the Poverty with the syn-sedimentary, ductile shear zones found within the Specchio mass transport complex. The seismic signature of such structures suggests localized fluid overpressure along detachment/thrust zones due to shearing and loading of undrained, water-saturated, fine-grained material, developed along with the slide mass movement. The outcrop expression of these structures is tentatively attributed to m- to tens of m-thick shear zones comprising large amounts of sedimentary matrix which separate and accommodate the differential movements of the internal slide components (e.g. slide blocks, olistoliths). The sedimentary matrix is an unsorted, lithologically mixed medium characterized by a scale-invariant “block-in-matrix” fabric (i.e. brecciated, mud-supported), that injects, sustain and surrounds discrete slide elements (from particles to blocks) and interpreted as a hyper-concentrated (liquefied/fluidized) suspension of water and scattered sediments developed in fluid overpressure conditions. We highlight the fundamental role of shearing-related liquefaction as one of the main factors controlling slide mobility through the “lubrication” of the internal and basal friction forces. The analysis of such features can therefore provide important information for the characterization of mass transport deposits developed from potentially catastrophic, long run-out mass transport events, and consequently, to better understand their possible socio-economic impact in terms of tsunamigenic potential.
•Reactivation and amalgamation of different bodies within mass transport deposits•Basal and internal fluid overpressure-related liquefaction in shear zones•Shear zones identified in seismic as high amplitude, inverse-polarity reflector(s)•Shear zones identified in outcrop as intervals of liquefied sedimentary matrix•Integrated, scale-invariant study of comparable outcrop and geophysical analogs
Alpha-1 deficiency in severe asthma patients Zappa, M.; Grossi, S.; Pignatti, P. ...
The international journal of tuberculosis and lung disease,
05/2024, Letnik:
28, Številka:
5
Journal Article
Recenzirano
INTRODUCTION Alpha-1 antitrypsin (AAT) deficiency, an autosomal co-dominant condition, decreases protein concentration and activity at both serum and tissue levels. Few studies investigated whether ...the type of SERPINA1 gene phenotype
in patients with severe asthma can influence symptoms and disease control during follow-up. OBJECTIVE To assess whether the presence of a non-MM genotype of SERPINA1 in patients with severe asthma is associated with disease
control, systemic and airway inflammation, lung function and comorbidities prevalence compared to severe asthma patients with a homozygous genotype (MM). METHODS Asthmatic patients belonging to Global Initiative for Asthma (GINA)
step 5 were retrospectively analysed in an Italian reference asthma clinic. We collected clinical, biological and functional variables at baseline and for the three following years. RESULTS Out of 73 patients enrolled, 14 (19.18%)
were non-MM and 59 (80.8%) were MM. Asthmatics with non-MM genotype had lower serum AAT concentration (P = 0.004) and higher emphysema prevalence than the MM group (P = 0.003) at baseline. During follow up, only MM patients showed a significant improvement of both ACQ-6 score
(P < 0.0001) and eosinophilic systemic inflammation (P < 0.0001). CONCLUSIONS Our findings emphasise the importance of a screening for AAT deficiency in severe asthma, as alleles mutation may influence patient's
follow-up.
Purpose
Vertebral fractures (VFs) were described in elderly patients with heart failure (HF) whereas their prevalence and determinants in younger HF patients are still unknown. This study aimed at ...assessing whether secondary hyperparathyroidism (SHPT) may influence the risk of VFs in middle-aged patients with HF.
Methods
84 patients (44 males, median age 48.5 years, range 43–65) with HF were prospectively evaluated at the baseline and after 36-month follow-up for bone mineral density (BMD) and VFs by quantitative morphometry on chest X-rays. Serum PTH, calcium, 25-hydroxyvitamin D and 24-h-urinary calcium were evaluated at the baseline and every 6–12 months during the study period.
Results
At baseline, SHPT, hypovitaminosis D and VFs were found in 43 patients (51.2%), 73 patients (86.9%) and 29 patients (34.5%), respectively. SHPT was associated with VFs at baseline inverse probability-weighted (ipw) odds ratio (OR) 12.2,
p
< 0.001. Patients were treated with vitamin D3 alone (56%), vitamin D3 plus calcium carbonate (21.4%), calcitriol alone (4.8%), bisphosphonates plus vitamin D3 (8.3%) or a combination of bisphosphonates, vitamin D3 and calcium carbonate (9.5%). At the end of follow-up, hypovitaminosis D was corrected in all patients, whereas 19/84 patients (22.6%) had persistent SHPT. During the follow-up, 16 patients developed incident VFs which resulted to be associated with baseline SHPT (ipw OR 55.7,
p
< 0.001), even after adjusting from BMD change from baseline to follow-up (ipw OR 46.4,
p
< 0.001).
Conclusions
This study provides a first evidence that SHPT may be a risk factor for VFs in middle-aged patients with HF.
Intense stratal disruption and lithological mixing is generated during sedimentary transport events, highlighting that gravitational processes are efficient mechanisms in the production of different ...types of mass transport deposits (MTDs) with internal block-in-matrix arrangement. Extra- and intrabasinal MTDs exhumed in orogenic belts worldwide, identified as olistostromes and sedimentary mélanges in the first case, record the final products of the downslope evolution of landslide masses, from slope failures to gravity flows. Specific sedimentary fingerprints are commonly preserved within such “chaotic” rock units, even though usually reworked by polyphased tectonics and associated metamorphism. One of the main conceptual issues in this framework is the occurrence/incorporation of “exotic” clasts and blocks (baseline criterion for mélange definition). We here provide an outline of the primary, multi-scale structures identified in key case studies from the northern Apennines of Italy and the northwestern Dinarides in Slovenia. We focus on mechanisms responsible for the entrainment of intra- (native) and extra- (exotic) basinal material and its progressive deformation. Important information, such as the kinematics of processes and internal strain partitioning, can be reconstructed from the study of such features, providing fundamental paleographic and paleo-physiographic constraints, as well as consolidating the basis for a possible updated reappraisal of some classic mélanges.
Display omitted
•(Un)mixing of intra- (native) and extrabasinal (exotic) material;•Deep basal substrate erosion during slide emplacement;•Rearrangement of depositional physiography by removal of paleobathymetric highs;•Slide detachment undercutting into older tectonic-stratigraphic units.
We report for the first time the detection of
Scirtothrips dorsalis
Hood (Thysanoptera: Thripidae) in Brazil and describe the occurrence of the thrips on leaves of ungrafted dwarf-cashew
Anacardium ...occidentale
Linnaeus 1753 (Anacardiaceae), maintained into a greenhouse, in the northeastern state of Ceará. This exotic polyphagous species listed as absent quarantine pest in the country is originated in Asia, but since the beginning of this century, it has readily dispersed despite the strict quarantine regulations currently in several countries. Individuals of
S. dorsalis
identified in Brazil are similar to specimens found in South Africa rather than Asia by virtue of the absence of conspicuous reticulation on the posterior half of the metanotum and the presence of complete lines of microtrichia restricted to the posterior part of the abdominal sternites.
Scirtothrips dorsalis
is a particularly invasive pest and its introduction represents a potential threat to various crops in Brazil, especially mango.
During the Miocene, hydrocarbon seep-carbonates located atop intrabasinal highs and associated with sediment instability, formed commonly at the deformation front of the Northern Apennine collisional ...orogen. The parallelism between the structural trend and the distribution of seep-carbonates suggests a close relationship between tectonics and gas/fluid emission.
The “Montepetra intrabasinal high” was formed during the closure stage of the foredeep, being related to the synsedimentary growth of an anticline. Field geometry suggests that detachment folding was the leading mechanism of anticline growth and synsedimentary instability along the anticline flanks. Ten different bodies of seep-carbonates occur in the Tortonian–early Messinian sediments: nine in the hinge zone and one in the southern backlimb of the anticline.
Foraminiferal study, geochemistry, facies investigation and the three-dimensional geometry of carbonate bodies with respect to the encasing terrigenous sediments indicate a protracted (late Tortonian–early Messinian) activity of fluid migration with re-mobilization and ascent of sediments from the core of the anticline, stabilization of chemosynthesis-related communities, and in-situ brecciation.
Seepage atop the intrabasinal high was fed by different circuits: one related to the compaction-dewatering of shallow (Tortonian–early Messinian) sediments, and a deeper one related to the deformation of the anticline core and to the activity of detachment surfaces and of faults propagating through the sedimentary cover.
►Seep-carbonates display habitat heterogeneity and different energies of fluid flow. ►Seepage occurred atop an intrabasinal high related to synsedimentary fold growth. ►High depositional load and fold geometry generated a long-term seafloor seepage. ►Deformation of fold core and detachment surfaces supplied deeper fluids. ►Gas hydrate dissociation favoured more intense fluid flow and sand/mud diapirism.
Abstract The objective of this study was to evaluate the Holopothrips fulvus Morgan (Thysanoptera: Phlaeothripidae) population dynamics and to identify dwarf cashew genotypes less infested by the ...pest in 2015 and 2016, under field conditions. H. fulvus population evaluations were carried out by monthly observations in the plants and using a score scale varying from 0 to 4. H. fulvus infestation occurred from October to December, and in the cashew genotypes CAP 112/8, CAP 121/1, CAP 131/2, CAP 145/2, CAP 145/7, CAP 128/2, CAP 120/4, CAP 123/6, CAP 130/1, and CAP 157/2 was dependent on the flowering period of the crop in 2015. In 2016, there was dependence in all evaluated genotypes between H. fulvus infestation and the cashew flowering period. In 2015, no significant differences were observed between the evaluated genotypes regarding H. fulvus infestation. In 2016, genotypes CAP 105/5, CAP 143/7, CAP 150/3, CAP 155/2, CAP 158/8, CAP 161/7, CAP 163/8, CAP 31, CAP 71, CAP 92, CAP 113, CAP 120, CAP 155, CAP 165, CAP 106/1, CAP 111/2, CAP 127/3, CAP 157/2, and BRS 226 were less infested. H. fulvus occurs from October to December and we could identify the dwarf cashew genotypes less infested by the pest.
PDF
