Great progress has been made in understanding the atomic structure of metallic glasses, but there is still no clear connection between atomic structure and glass-forming ability. Here we give new ...insights into perhaps the most important question in the field of amorphous metals: how can glass-forming ability be predicted from atomic structure? We give a new approach to modelling metallic glass atomic structures by solving three long-standing problems: we discover a new family of structural defects that discourage glass formation; we impose efficient local packing around all atoms simultaneously; and we enforce structural self-consistency. Fewer than a dozen binary structures satisfy these constraints, but extra degrees of freedom in structures with three or more different atom sizes significantly expand the number of relatively stable, 'bulk' metallic glasses. The present work gives a new approach towards achieving the long-sought goal of a predictive capability for bulk metallic glasses.
The models recognize that ZrSiO4, ZrTiO4, and TiSiO4, but not ZrO2 or TiO2, are independently variable phase components in zircon. Accordingly, the equilibrium controlling the Zr content of rutile ...coexisting with zircon is ZrSiO4 = ZrO2 (in rutile) + SiO2. The equilibrium controlling the Ti content of zircon is either ZrSiO4 + TiO2 = ZrTiO4 + SiO2 or TiO2 + SiO2 = TiSiO4, depending whether Ti substitutes for Si or Zr. The Zr content of rutile thus depends on the activity of SiO2 alpha SiO{2} as well as T, and the Ti content of zircon depends on alpha SiO {2} and alpha TiO{2} as well as T. New and published experimental data confirm the predicted increase in the Zr content of rutile with decreasing alpha SiO{2} and unequivocally demonstrate that the Ti content of zircon increases with decreasing alpha SiO{2}. The substitution of Ti in zircon therefore is primarily for Si. Assuming a constant effect of P, unit alpha ZrSiO{4} and that alpha ZrO{2} and alpha ZrTiO{4} are proportional to ppm Zr in rutile and ppm Ti in zircon, log(ppm Zr-in-rutile) + log alpha SiO{2} = A1 + B1/T(K) and log(ppm Ti-in-zircon) + log alpha SiO{2}-log alpha TiO{2} = A2 + B2/T, where the A and B are constants. The constants were derived from published and new data from experiments with alpha SiO{2} buffered by either quartz or zircon + zirconia, from experiments with alpha SiO{2} defined by the Zr content of rutile, and from well-characterized natural samples. Results are A1 = 7.420 +/- 0.105; B1 = -4,530 +/- 111; A2 = 5.711 +/- 0.072; B2 = -4,800 +/- 86 with activity referenced to alpha-quartz and rutile at P and T of interest. The zircon thermometer may now be applied to rocks without quartz and/or rutile, and the rutile thermometer applied to rocks without quartz, provided that alpha SiO{2} and alpha TiO{2} are estimated. Maximum uncertainties introduced to zircon and rutile thermometry by unconstrained alpha SiO{2}} and alpha TiO{2} can be quantitatively assessed and are (symbol omitted) 60 to 70 degrees C at 750 degrees C. A preliminary assessment of the dependence of the two thermometers on P predicts that an uncertainty of +/- GPa introduces an additional uncertainty at 750 degrees C of (symbol omitted) 50 degrees C for the Ti-in-zircon thermometer and of (symbol omitted) 70 to 80 degrees C for the Zr-in-rutile thermometer. PUBLICATION ABSTRACT
As a result of the energy deposition of ionizing radiation in organic polymers and in organic compounds in general, excited and ionized species are formed. The latter can readily react with emitted ...electrons to form excited species that will eventually lead to macromolecular defects and gas emission - their counterpart. Charges from ionized species and excitations can also be transferred, and trapped, far from their creation sites before leading to defects creation. In dense materials submitted to irradiation, excitations, charge transfer or mass transport from one molecule to the other has been proven to happen since the early 1930's in organic molecules mixtures and the 1950's in polymers. Radical stemming from the evolution of the excited molecules, which results either from direct energy deposition by the radiations or from the electron-hole recombination, can also migrate before being trapped or reacting, on a site far from its creation site. Radical, excitation, electron and hole transfers are gathered in the generic term of energy transfer. In this review is presented an overview on the research performed in this field. We evaluate the influence of different parameters that can alter the efficiency of energy transfer: these can be related to the polymer composition (chemical structure of the molecules composing the monomers or the additives inserted in the bulk) or to the irradiation characteristics (radiation type among ionizing radiations, dose and temperature for example). To get rid of the complexity brought by the polymer structure and the existence of different levels of organization, polymers are sometimes modelled by molecules, either pure or as mixtures. To take this into account, some studies on energy transfer in molecule mixtures are also presented.
•Energy transfers along with their underlying mechanisms are defined.•Evidences of these energy transfers in organic molecules and polymers are given.•Irradiation parameters influence is evaluated.
The intention of the present study is to review and compare the effect of various well-studied alloying elements on the microstructure and soft magnetic properties of the Fe-based ...amorphous/nanocrystalline system. The state-of-the-art Fe-based amorphous/nanocrystalline alloys have been developed because of their unique soft magnetic properties such as low core loss, high permeability(104–105 at 1kHz) and low magnetostriction (<10ppm) as compared to conventional silicon steels which are also called electrical steels. In Fe-based amorphous/nanocrystalline system, the chemical composition and microstructural features particularly grain size play an indispensable role on the saturated magnetization (Bs) and coercivity (Hc) values. An ideal Fe-based soft magnetic material is defined as a material possessing higher Bs and lower Hc. The problem of the new material is its low Bs value (for commercial material is 1.4T) than silicon steels (≈2T). In addition to Bs content of new material, many attempts have been made to reduce the Hc value which could be achieved via a decrease of grain size (<50nm). To reach this goal (Bs↑ and Hc↓), the effect of a variety of elements on the microstructure, crystallization process and soft magnetic properties of the Fe-based amorphous/nanocrystalline alloys has been investigated so far. The aim of all these studies is to find an appropriate replacement for conventional silicon steels because of their high core loss and low permeability. Effect of alloying elements including Si, B, Cu, Nb, Zr, N-doping, P, Ni, Co, H-doping, Ge and W on the microstructure and magnetic properties is the main subject of this study in order to shed light on the dependence of magnetic properties with composition and grain size.
•N-doped alloys showedsuperior soft magnetic properties.•Cu and Nb are the most effective elements in refining grain size.•Soft magnetic properties highly depends on the primary composition and grain size.
•We have created an operationally functional battery dispatch algorithm for DCM.•Battery discharge (with a PV array) was simulated to reduce demand charges.•The dispatch scheme reduced the daily peak ...load on average 23% against the baseline.•Typical discharge behavior is characterized and subideal performance is discussed.•Eg, significant net overforecasting (PV and load) can cause total battery discharge.
A battery storage dispatch strategy that optimizes demand charge reduction in real-time was developed and the discharge of battery storage devices in a grid-connected, combined photovoltaic-battery storage system (PV+system) was simulated for a summer month, July 2012, and a winter month, November 2012, in an operational environment. The problem is formulated as a linear programming (LP; or linear optimization) routine and daily minimization of peak non-coincident demand is sought to evaluate the robustness, reliability, and consistency of the battery dispatch algorithm. The LP routine leverages solar power and load forecasts to establish a load demand target (i.e., a minimum threshold to which demand can be reduced using a photovoltaic (PV) array and battery array) that is adjusted throughout the day in response to forecast error. The LP routine perfectly minimizes demand charge but forecasts errors necessitate adjustments to the perfect dispatch schedule. The PV+system consistently reduced non-coincident demand on a metered load that has an elevated diurnal (i.e., daytime) peak. The average reduction in peak demand on weekdays (days that contain the elevated load peak) was 25.6% in July and 20.5% in November. By itself, the PV array (excluding the battery array) reduced the peak demand on average 19.6% in July and 11.4% in November. PV alone cannot perfectly mitigate load spikes due to inherent variability; the inclusion of a storage device reduced the peak demand a further 6.0% in July and 9.3% in November. Circumstances affecting algorithm robustness and peak reduction reliability are discussed.
Metastatic and locally-advanced neuroendocrine neoplasms (aNEN) form clinically and genetically heterogeneous malignancies, characterized by distinct prognoses based upon primary tumor localization, ...functionality, grade, proliferation index and diverse outcomes to treatment. Here, we report the mutational landscape of 85 whole-genome sequenced aNEN. This landscape reveals distinct genomic subpopulations of aNEN based on primary localization and differentiation grade; we observe relatively high tumor mutational burdens (TMB) in neuroendocrine carcinoma (average 5.45 somatic mutations per megabase) with TP53, KRAS, RB1, CSMD3, APC, CSMD1, LRATD2, TRRAP and MYC as major drivers versus an overall low TMB in neuroendocrine tumors (1.09). Furthermore, we observe distinct drivers which are enriched in somatic aberrations in pancreatic (MEN1, ATRX, DAXX, DMD and CREBBP) and midgut-derived neuroendocrine tumors (CDKN1B). Finally, 49% of aNEN patients reveal potential therapeutic targets based upon actionable (and responsive) somatic aberrations within their genome; potentially directing improvements in aNEN treatment strategies.
OBJECTIVE: To develop and validate a quantitative real-time polymerase chain reaction (qPCR)–based method for blastocyst trophectoderm comprehensive chromosome screening (CCS) of aneuploidy. DESIGN: ...Prospective, randomized, and blinded. SETTING: Academic center for reproductive medicine. PATIENT(S): Nine cell lines were obtained from a commercial cell line repository, and 71 discarded human blastocysts were obtained from 24 IVF patients that underwent preimplantation genetic screening. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Consistency of qPCR diagnosis of aneuploidy compared with either conventional karyotyping of cell lines or microarray-based diagnoses of human blastocysts. RESULT(S): Samples from nine cell lines with well characterized karyotypes were diagnosed by qPCR with 97.6% (41/42) consistency. After applying a minimum threshold for concurrence, 100% consistency was achieved. Developmentally normal blastocysts designated as aneuploid or arrested blastocysts designated as euploid by single-nucleotide polymorphism microarray analyses were assigned identical 24 chromosome diagnoses by qPCR in 98.6% of cases (70/71). Overall euploidy (n = 37) and aneuploidy (n = 34) were assigned with 100% consistency. Data was obtained for both sample types in 4 hours. CONCLUSION(S): These data demonstrate the first qPCR technology capable of accurate aneuploidy screening of all 24 chromosomes in 4 hours. This methodology provides an opportunity to evaluate trophectoderm biopsies with subsequent fresh euploid blastocyst transfer. Randomized controlled trials to investigate the clinical efficacy of qPCR-based CCS are currently underway.
•We developed a modeling and resolution framework for wrinkling and restabilization in both compressible and incompressible hyperelastic sheets.•2D hyperelastic plate models were systematically ...derived from general 3D strain energy functions.•A novel, efficient and robust numerical algorithm through coupling of a spectral collocation method and Asymptotic Numerical Method was proposed.•The first attempt to ameliorate a spectral method for nonlinear instability resolution with real boundary conditions was achieved.•Effects of Poisson’s ratio and strain-stiffening behavior on post-buckling evolution were investigated.
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Wrinkles commonly occur in uniaxially stretched rectangular hyperelastic membranes with clamped-clamped boundaries, and can vanish upon excess stretching. Here we develop a modeling and resolution framework to solve this complex instability problem with highly geometric and material nonlinearities. We extend the nonlinear Föppl-von Kármán thin plate model to finite membrane strain regime for various compressible and incompressible hyperelastic materials. Under plane stress condition, 2D hyperelastic constitutive models can be systematically deduced based on general 3D strain energy potentials, e.g., Saint-Venant Kirchhoff, neo-Hookean, Mooney-Rivlin, Gent model and Gent-Gent model. Moreover, we establish a novel and efficient numerical resolution framework combining a path-following continuation technique by Asymptotic Numerical Method (ANM) and a discretization by a spectral method. The main advantages of this framework include the generality for both compressible and incompressible materials, ease of programming, high precision and efficient continuation predictor. Based on the proposed approach, effect of different incompressible constitutive models on the post-buckling response is investigated, which shows that restabilization points and wrinkling amplitudes are quantitatively influenced. However, for compressible materials, Poisson’s ratio plays a critical role in the wrinkling and restabilization behavior. We find that smaller Poisson’s ratio makes later onset of wrinkling, lower amplitude and earlier disappearance of wrinkles. Besides, severe strain-stiffening phenomena are explored by accounting for phenomenological models such as Gent model and Gent-Gent model. Efficiency and accuracy of the proposed modeling and resolution framework were examined by comparing with some benchmarks.
To determine whether performing comprehensive chromosome screening (CCS) and transferring a single euploid blastocyst can result in an ongoing pregnancy rate that is equivalent to transferring two ...untested blastocysts while reducing the risk of multiple gestation.
Randomized, noninferiority trial.
Academic center for reproductive medicine.
Infertile couples (n = 205) with a female partner less than 43 years old having a serum anti-Müllerian hormone level ≥1.2 ng/mL and day 3 FSH <12 IU/L.
Randomization occurred when at least two blastocysts were suitable for trophectoderm biopsy. The study group (n = 89) had all viable blastocysts biopsied for real-time, polymerase chain reaction–based CCS and single euploid blastocyst transfer. The control group (n = 86) had their two best-quality, untested blastocysts transferred.
The ongoing pregnancy rate to ≥24 weeks (primary outcome) and the multiple gestation rate.
The ongoing pregnancy rate per randomized patient after the first ET was similar between groups (60.7% after single euploid blastocyst transfer vs. 65.1% after untested two-blastocyst transfer; relative risk RR, 0.9; 95% confidence interval CI, 0.7–1.2). A difference of greater than 20% in favor of two-blastocyst transfer was excluded. The risk of multiple gestation was reduced after single euploid blastocyst transfer (53.4% to 0%), and patients were nearly twice as likely to have an ongoing singleton pregnancy (60.7% vs. 33.7%; RR, 1.8; 95% CI, 1.3–2.5).
In women ≤42 years old, transferring a single euploid blastocyst results in ongoing pregnancy rates that are the same as transferring two untested blastocysts while dramatically reducing the risk of twins.
NCT01408433.
No standard treatment is available for advanced biliary tract cancer (BTC) after first-line therapy with gemcitabine plus cisplatin (GEMCIS). The objective of this study was to evaluate safety and ...anti-tumour activity of fluorouracil, leucovorin, irinotecan plus oxaliplatin (FOLFIRINOX) as salvage treatment in patients with previously treated advanced BTC.
In this two-stage phase 2 study, patients with advanced BTC who had disease progression or unacceptable toxicity after ≥3 cycles of GEMCIS were eligible. Primary endpoints were safety and efficacy (defined as objective response rate, ORR). In stage one, ten patients were treated with FOLFIRINOX every 2 weeks. In stage two, an additional 20 patients were enrolled at a starting dose as defined in stage one, provided that in stage ≥1 objective response or ≥2 stable diseases were observed and ≤3 patients had serious adverse events (SAEs) within the first 6 weeks of treatment. Secondary endpoints were progression-free survival (PFS) and overall survival (OS).
Forty patients were screened for eligibility and 30 patients were enrolled. In stage one, one patient had a partial response and five patients had stable disease. One patient had a SAE during the first 6 weeks of treatment, and five patients required a dose reduction due to adverse events. The most common grade 3-4 adverse events in stage one were neutropaenia, mucositis and diarrhoea. Stage two was initiated with FOLFIRINOX in an adapted dose. In stage two, grade 3-4 neutropaenia, diarrhoea, nausea and vomiting were the most common adverse events. The ORR, median PFS and OS in all patients were 10%, 6.2 and 10.7 months, respectively.
In patients with advanced BTC who progressed after or were intolerant to GEMCIS, FOLFIRINOX can be administered safely and could be considered as an option for salvage treatment in these patients.
ClinicalTrials.gov Identifier NCT02456714.
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