Salt lithologies are mechanically weaker than other sedimentary rocks. Salt horizons usually act as décollements and precursor salt bodies preferentially deform early during contraction, concentrate ...deformation, and impact the structural style and kinematics during mountain building. Focusing on shortened isolated-diapir provinces, our analog modeling program investigates the influence of two salt walls on folding and thrusting.
High resolution topographic scans and particle image analysis show that the presence of precursor diapirs impacts the layer parallel shortening patterns and presumably the stress field at the onset of contraction. Shortening concentrates on diapirs, leading to roof arching, crestal extension and salt extrusion. This sequence of events occurs earlier on thinner salt-sediment sequences including diapirs having well-developed pedestals, particularly when proximal to the deformation front. Folds and thrusts nucleate at salt walls if they feature a well-developed pedestal. Further shortening results in secondary welding as evidenced by the collapse of uplifted roof domes, cessation of indentation and reverse faulting nucleated at the secondary welds. Meanwhile, and depending upon the processes occurring on the diapir closer to the backstop, the deformation of the distal salt wall is discontinuous.
Our modeling results are compared with experimental works and natural examples from the Fars (Zagros Mountains).
•Salt bodies are weak discontinuities that modify layer-parallel shortening patterns.•Well-developed salt pedestals lead to the nucleation of thrust-wedge structures.•Diapir rejuvenation accelerates with the closeness to the deformation front.•Secondary welding is evidenced by extrusion summit dome collapses.•Deformation of frontal salt bodies depends upon hindward-located ones.
Contractional deformation in salt-bearing rifted- and convergent-margin settings often involves diapirism. Diapirs may predate the onset of shortening, such that they exert a pronounced influence on ...how contractional strain is accommodated, or they may be triggered by the shortening. Analog models have been used to help understand the interaction and evolution of detachment folds, thrust faults, and diapirs, but few surface or subsurface datasets provide adequate three-dimensional images to test and refine the experimental results. Here we use 3D depth-migrated seismic data from the Sureste Basin, offshore SE Mexico, to map two structures, one dominated by salt-cored anticlines and one characterized by thrust faults. Associated diapirs include both pre- and syncontractional stocks and walls. We show that although analog models in the literature nicely reproduce some of the seismic geometries, there are also apparent mismatches. Whereas models often generate decapitated diapirs and thrust-fault salients centered on the diapirs, such features are absent in the study area. Moreover, in contrast to model thrust faults that dip 20-45°, faults in the study area are steeper, ranging from 50 to 75°. We bring in observations from other salt basins to discuss these discrepancies, possible explanations, and suggestions for improving the applicability of models to nature.
•The Sureste Basin, Mexico, experienced both gravitational and orogenic shortening.•Salt diapirs include both preexisting and syncontractional stocks and walls.•The 3D geometries of folds, thrusts, and diapirs are compared to analog models.•Diapir decapitation and thrust salients are common in models but rare in nature.•Observed thrust faults are usually steeper than those generated in models.
Purpose
The advantages of biological meshes for ventral hernia repair are still under debate. Given the high financial cost, the proper indications for biological meshes should be clarified to ...restrict their use to properly selected patients.
Methods
A retrospective database was instituted to register all cases of abdominal wall defect treated with biological meshes from 1/2010 to 3/2016.
Results
A total of 227 patients (mean age: 64 years) whose ventral abdominal defects were reconstructed with a biological mesh were included in the study. Patients were divided according to the 2010 four-level surgical-site complication risk grading system proposed by the Ventral Hernia Working Group (VHWG): Grade 1 (G1, 12 cases), Grade 2 (G2, 68 cases), Grade 3 (G3, 112 cases), and Grade 4 (G4, 35 cases). The surgical site complication rate was higher in patients with one or more risk factors (33.6% vs 19% in patients with no risk factors) (
P
= 0.68). Statistically significant risk factors associated with the onset of one or more postoperative surgical site complications included: diabetes, coronary artery disease, immunosuppression, and obesity. Recurrence was more common in patients with surgical site complications and mainly associated with infection (38.9%) and wound necrosis (44.4%), and in cases of inlay positioning of the mesh (36%).
Conclusions
Due to their high costs, biological mesh should not be used in G1 patients. In infected fields (G4), they should only be used if no other surgical solution is feasible. There is a clear need to prospectively evaluate the performance of biological meshes.
Web searches from mobile devices such as PDAs and cell phones are becoming increasingly popular. However, the traditional list‐based search interface paradigm does not scale well to mobile devices ...due to their inherent limitations. In this article, we investigate the application of search results clustering, used with some success for desktop computer searches, to the mobile scenario. Building on CREDO (Conceptual Reorganization of Documents), a Web clustering engine based on concept lattices, we present its mobile versions Credino and SmartCREDO, for PDAs and cell phones, respectively. Next, we evaluate the retrieval performance of the three prototype systems. We measure the effectiveness of their clustered results compared to a ranked list of results on a subtopic retrieval task, by means of the device‐independent notion of subtopic reach time together with a reusable test collection built from Wikipedia ambiguous entries. Then, we make a cross‐comparison of methods (i.e., clustering and ranked list) and devices (i.e., desktop, PDA, and cell phone), using an interactive information‐finding task performed by external participants. The main finding is that clustering engines are a viable complementary approach to plain search engines both for desktop and mobile searches especially, but not only, for multitopic informational queries.
Food Products Containing Inedibles (FPCIs) are believed to represent a source of higher choking risk in children. The aim of this study was to set up a controlled study, conducted on children aged ...3–6 in a laboratory setting, in order to understand their behavior when interacting with FPCIs (with reference to mouthing activities, double nature recognition, and toy assembling ability).
The experimental phase was divided into two sessions: a FPCI session and a Toy session, to which 247 children were randomly assigned. During these sessions children were observed in order to catch their mouthing activity according to the two types of objects available to them (FPCIs and Toys).
This study shows that: (a) children's behavior with respect to toys contained in FPCIs and toys presented alone is not significantly different; (b) children's ability to distinguish between the edible and non-edible part of the FPCI was very high; and (c) mouthing episodes of the inedible parts were negligible and comparable between FPCIs and toys presented alone. This strongly suggests that, with respect to choking risk, FPCIs are not per se distinguishable from toys containing small parts.
Restrictions on the sale of FPCIs with small toys exist in the U.S. market. In Europe, FPCIs are allowed to be on sale, under the condition that, in case, they will follow the general regulatory requirements of small toys packaged and sold alone. In this case, they must provide age warnings and labels. Our findings do not justify the different attention that toys in FPCIs are at times afforded by regulators when compared to “stand alone” toys.
To study the pattern of foreign bodies in the upper airways as emerging from the hospital records in the Bologna and Siena hospitals in Italy 1997-2002.
A retrospective review of hospital records was ...performed using a standardized protocol. All injuries with ICD9 (International Classification of Diseases, 9'h revision) codes ranging from 931 to 934 which occurred in children age 0-14 were considered for the database.
One hundred ninety seven patients were included in the database with a diagnosis of Foreign Bodies (FB) over the study period, 78 with ICD931, 105 with ICD932, 12 with ICD933 and 2 with ICD934 discharge diagnosis. Of the 197 patients, 51.90% of the patients were males and the 48.10% were female. Median age was 4 (2, 6). At the moment of the injury, the child was eating (11%), playing (83%) or studying (4%) or cleaning ears (2%). The child was supervised by an adult in doing his/her activities at the moment of injury in the 84.2% of the cases. The child reached the hospital using always private transport (100%), never by using an emergency transport (0%). Most commonly, FB were extracted in ambulatory (95.4%), more rarely using an endoscopic procedure (4.1%), and never using surgery. Hospitalization was required in the 0.5% of cases (1).
Our study showed the substantial epidemiological similarity of the Italian data with the experience of other center in the world. The burden of chocking was very limited in our country, as proven by the limited access to emergency and more invasive procedures. Nevertheless, some consideration can be made from the preventive point of view. Quite surprisingly, the majority of injuries occurred under the supervision of an adult in playing or recreational activities.
Psychological aspects determining children's behaviour in response to asphyxiation risk due to ingestion of foreign matter have been rarely and non-systematically examined in the literature. Aim of ...this report is to highlight--through a review of the most significant psychological research in the literature--which factors influence the behaviour, perception and assessments of children 0 to 14 years of age, in a risk situation. In particular, attention is focused on the direct experience of a child at risk, assuming that this experience can play a significant role in future dangerous situations. Outcomes of studies taken into consideration have highlighted the influence of age, sex, socio-economic status, parents' role, peer group, personal traits, television and personal experience. The latter refutes the initial hypotheses, showing an unexpected and clearly negative effect on future evaluation and behaviour in response to similar contexts of asphyxiation risk. The implications for research on asphyxiation due to ingestion of foreign matter are examined.
The highly conductive p‐type surface layer that can be induced in diamond by hydrogen termination is very attractive for electrical applications and in particular for the design of in‐plane devices. ...In this paper we will present our work on the characterization of sub‐micron in‐plane transistors. Two different approaches have been analyzed for the design of the transistor gate. First of all the properties of Al gates on H‐terminated diamond will be discussed, focusing on their capacitance–voltage characteristics. As a result of this study it will be shown how the p‐type surface layers in H‐terminated diamond behaves like a two‐dimensional system. However, due to the poor channel control by the Al gates another approach was followed. The gate region is separated from the channel by a thin oxidized line. The channel current is controlled by the voltage applied to the gate, which varies the space charge region width that is formed at the oxidized line. Sub‐micron gate structures were generated by using e‐beam lithography and a plasma oxidation treatment. The transistor characteristics of the in‐plane diamond structures are presented in this paper.
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