The Effect of Deformation on Clumped Isotope Concentration in Calcite

The use of clumped isotope analysis in calcite is a rapidly developing and powerful technique for paleothermometry studies in tectonics and environmental sciences. For analysis of isotopes in deformed rocks, there is uncertainty if the deformation of the calcite can reset clumped isotope concentrations, which limits the utility of the method. The goal of this research is to help determine if some typical deformation processes, specifically plastic deformation of calcite at low temperatures (˂200 C), can affect clumped isotope concentrations. Seven cores of calcite are deformed experimentally at strain rates 2-4.2x10⁻⁵ s⁻¹ , temperatures from 20 – 400 C, at confining pressure of 150-200 MPa, and to strains of 10-25%. The cores are taken from parent crystals in four different orientations relative to the crystallographic directions of calcite in order to induce different types of deformation. The deformed samples were studied using optical microscopy and electron backscatter diffraction microscopy techniques to identify the types of plastic deformation that operated in each test. Both mechanical e-twinning and r- and r+ slip were successfully activated, and to varying degrees, in the sample suite. Yield strengths observed in the experiments agree well with that expected (based on previous work) for the twin and slip mechanisms identified through microscopy. On the basis of the outcomes of this research, clumped isotope measurements of the parent crystals and the deformed samples will determine if, and which deformation processes affect isotope concentrations. If isotope concentrations remain unchanged by deformation, then the reliability of clumped isotope analysis in deformed rocks will be assured. If deformation resets clumped isotope concentrations, then with further research the method holds great promise to determine the temperature at the time of deformation, which would be a unique capability

The Effect of Deformation on Clumped Isotope Concentration in Calcite

The use of clumped isotope analysis in calcite is a rapidly developing and powerful technique for paleothermometry studies in tectonics and environmental sciences. For analysis of isotopes in deformed rocks, there is uncertainty if the deformation of the calcite can reset clumped isotope concentrations, which limits the utility of the method. The goal of this research is to help determine if some typical deformation processes, specifically plastic deformation of calcite at low temperatures (˂200 C), can affect clumped isotope concentrations. Seven cores of calcite are deformed experimentally at strain rates 2-4.2x10⁻⁵ s⁻¹ , temperatures from 20 – 400 C, at confining pressure of 150-200 MPa, and to strains of 10-25%. The cores are taken from parent crystals in four different orientations relative to the crystallographic directions of calcite in order to induce different types of deformation. The deformed samples were studied using optical microscopy and electron backscatter diffraction microscopy techniques to identify the types of plastic deformation that operated in each test. Both mechanical e-twinning and r- and r+ slip were successfully activated, and to varying degrees, in the sample suite. Yield strengths observed in the experiments agree well with that expected (based on previous work) for the twin and slip mechanisms identified through microscopy. On the basis of the outcomes of this research, clumped isotope measurements of the parent crystals and the deformed samples will determine if, and which deformation processes affect isotope concentrations. If isotope concentrations remain unchanged by deformation, then the reliability of clumped isotope analysis in deformed rocks will be assured. If deformation resets clumped isotope concentrations, then with further research the method holds great promise to determine the temperature at the time of deformation, which would be a unique capability

Is it more dangerous to perform inadequate packing?

Peri-hepatic packing procedure, which is the basic damage control technique for the treatment of hepatic hemorrhage, is one of the cornerstones of the surgical strategy for abdominal trauma. The purpose of this study was to evaluate the efficacy of the perihepatic packing procedure by comparing the outcomes of appropriately and inappropriately performed interventions. Trauma patients with liver injury were retrospectively evaluated. The patients who had undergone adequate packing were classified as Group A, and the patients who had undergone inappropriate packing, as Group B. Over a five-year period, nineteen patients underwent perihepatic packing. Thirteen of these patients were referred by other hospitals. Of 13 patients, 9 with inappropriate packing procedure due to insertion of intraabdominal drainage catheter (n=4) and underpacking (n=5) were evaluated in Group B, and the others (n=10) with adequate packing were assessed in Group A. Mean 3 units of blood were transfused in Group A and unpacking procedure was performed in the 24th hour. Only 3 (30%) patients required segment resection with homeostasis, and the mortality rate was 20% (2/10 patients). In Group B, 4 patients required repacking in the first 6 hrs. Mean 8 units of blood were transfused until unpacking procedure. The mortality rate was 44% (4/9 patients). The length of intensive care unit stay and requirement of blood transfusion were statistically significantly lower in Group A (p < 0.05). The mortality rate of this group was also lower. However, the difference between the groups for mortality rates was not statistically significant. This study emphasizes that efficacy of the procedure is one of the determinants that affects the results, and inadequate or inappropriate packing may easily result in poor outcome

Comperative Analysis of Problem Posing Ability Between the Anatolian High School Students and the Public High School Students Located in Bagcilar District of Istanbul

AbstractThe purpose of this case study was to investigate the problem posing abilities of the “Anatolian High School” students and the “Public High School” students who had been studying in the Bagcilar district of the city of Istanbul.The methodology employed in the study was qualitative in nature. Document analysis method was applied. The participants, who had been successful for an exam carried out by a private course located in the district of Bagcilar of Istanbul, were including four “Anatolian High School” 11 th grade students and the other four “Public High School” 11 th grade students. In the research, students were provided with five different types of worksheets for problem posing Types of worksheets were including story editing, information translating, problem posing according to the previously defined equation, figure and result or conclusion. As a result of the study, two “Public High School” students could not accomplish the study concerning the problem posing according to the previously defined equation. On the other hand, the “Anatolian High School” students were much more successful than the “Public High School” students

Inhibited spontenaous emission of perylene dye molecules embedded in nano-cavities

Abstract:{|}The radiative properties of molecules placed in cavities differ fundamentally from the radiative properties in free space. Fluorescence lifetime measurements of perylene dye molecules in polymer nanocavities are experimentally studied using time-correlated single photon counting techniques. The fluorescence lifetime of perylene is measured to be 4.8 ns. Perylene is embedded into polyacrylonitrile nanofibers and polymethylmethacrylate films. Spontaneous emission rate of perylene is inhibited by a factor of up to 2.6. Thus, the enhancement of fluorescence lifetime of perylene from 4.8 ns to 12.36 us for polyacrylonitrile nanofibers and to 12.3 ns for polymethylmethacrylate films is observed

Ottoman Masonry Bridges in Anatolia and the Balkans

Remains of the historical masonry bridges in Anatolia and the Balkans are dated back to the Roman (first half of the I. Millenium AD), to the Seldjukide (early centuries of the II. Millenium AD; basically in Anatolia), and to the Ottoman periods (13th to 19th centuries). Besides serving to transportation, bridges crossing watercourses have to be considered as important hydraulic structures. Built for military as well as economic purposes, more than one hundred Ottoman bridges (roughly two thirds in Anatolia and one third in the Balkans) served for several centuries; some of them being still in operation. They are silent witnesses of the hydraulic knowledge and solid construction technology of their times. In this inventory study, only Ottoman's masonry bridges in Anatolia and Balkans have been presented. Some of the Ottoman's masonry bridges had sunken in the reservoir of modern dams, some of them demolished during the construction of the new highways, and some of them are still in service

Testing Flood Estimation Methods On Ancient Closed Conduits

Beside a large number of ancient tunnels in long-distance water conveyance systems toancient cities in Turkiye, five peculiar closed conduits, through which almost the entire discharge of water courses were flowing, are investigated. These are the Cevlik (Seleucia Pieria) tunnel inHatay province; vaulted structures covering the river bed in Bergama (Pergamon), in Sultanhisar(Nysa), in Acarlar near Ephesus (all four are leading examples of largest closed conduits from Roman times in the world); and the Bezirgan tunnel east of Kalkan, being an interesting example of emissary conduits draining the floods of closed basins. The hydraulic capacities of these conduits are determined; their corresponding flood return periods are estimated by four synthetic flood hydrograph methods. However, it was not possible to deduce any generalized conclusion based on the comparison of these results

Volumetric segmentation of multiple basal ganglia structures

We present a new active contour-based, statistical method for simultaneous volumetric segmentation of multiple subcortical structures in the brain. Neighboring anatomical structures in the human brain exhibit co-dependencies which can aid in segmentation, if properly analyzed and modeled. Motivated by this observation, we formulate the segmentation problem as a maximum a posteriori estimation problem, in which we incorporate statistical prior models on the shapes and inter-shape (relative) poses of the structures of interest. This provides a principled mechanism to bring high level information about the shapes and the relationships of anatomical structures into the segmentation problem. For learning the prior densities based on training data, we use a nonparametric multivariate kernel density estimation framework. We combine these priors with data in a variational framework, and develop an active contour-based iterative segmentation algorithm. We test our method on the problem of volumetric segmentation of basal ganglia structures in magnetic resonance (MR) images. We compare our technique with existing methods and demonstrate the improvements it provides in terms of segmentation accuracy

Utjecaj fitohormona na sposobnost zakorjenjivanja reznica vrste Ficus benjamina L.

Vegetative production techniques, of which cutting method widely used in propagation of ornamental plants, have a crucial role for conserving the plant genetic sources. On rooting development of stem cuttings, cutting position, rooting medium and rooting hormone are some of the critical factors that affect the success. The primary objective of this study is to determine the best hormone doses and ideal rooting medium on Ficus benjamina L. stem cuttings. Conventionally, the most frequently vegetative propagation method is the rooting of the stem cuttings in various media such as, pearlite, peat, sand, through exposure to high-concentration rooting hormones (IBA, IAA, NAA, etc.). But, this conventional technique requires wide areas in the rooting stage of mass production, prevents monitoring the course of rooting, and necessitates large amount of materials used as hormones and rooting media. In this study, a new method that may be preferable in mass production of plants was tested. 39 different treatments were carried out, and their results were evaluated. Sand, and perlite were used as solid rooting media. Stem cuttings were kept in low-concentration hormones permanently after cutting (liquid medium). In this way, their rooting capability were examined. Rooting trials were conducted before stem cuttings were taken to solid rooting media. As conclusions, the highest rooting ratio were obtained for 10 ppm of NAA (94.43%) and 100 ppm of IBA (93.9%) in liquid media. Moreover, the highest root length and the average root length were quite low in liquid media.Tehnike vegetativne proizvodnje od kojih se metoda reznica uvelike koristi u razmnožavanju ukrasnog bilja, imaju ključnu ulogu za očuvanje genetskih izvora biljaka. Mjesto uzimanja reznice na biljci, medij ukorjenjivanja i fitohormon ukorjenjivanja neki su od ključnih čimbenika koji utječu na uspjeh razvoja zakorjenjivanja reznica od stabljike. Primarni cilj ovog istraživanja bio je utvrditi najbolje koncentracije fitohormona i idealni medij zakorjenjivanja za reznice od stabljike vrste Ficus benjamina L. Konvencionalno, najčešća metoda vegetativnog razmnožavanja je zakorjenjivanja pupova u različitim supstratima kao što su perlit, treset, pijesak do izloženosti visoko koncentriranim hormonima zakorjenjivanja (IBA, IAA, NAA, itd.). Ali ta konvencionalna tehnika zahtijeva široka područja u fazi zakorjenjivanja masovne produkcije, sprječava nadzor tijeka zakorjenjivanja i traži visoku količinu materijala koji se koriste kao hormoni i mediji zakorjenjivanja. U ovom istraživanju, ispitana je nova metoda koja bi mogla biti poželjnijom u masovnoj proizvodnji biljaka. Izvršeno je 39 različitih tretiranja i prikazani su njihovi rezultati. Pijesak i perlit korišteni su kao kruti medij zakorjenjivanja. Pupovi su se trajno čuvali u hormonima niske koncentracije nakon rezanja (tekući medij). Na taj način je ispitana njihova sposobnost zakorjenjivanja. Ispitivanja zakorjenjivanja provedena su prije nego su pupovi odnijeti u kruti medij zakorjenjivanja. Kao zaključak, dobiveni su najviši omjeri zakorjenjivanja za 10 ppm NAA (94.43%) te 100 ppm IBA (93.9%) u tekućim medijima. Najveća duljina korijena i prosječna duljina korijena bile su prilično male u tekućim medijima