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Design and synthesis of thermodynamically metastable yet kinetically achievable materials possessing various desired functional and physical properties have recently drawn tremendous scientific-attention. In addition to conventional heat treatments and wet chemistry approaches, energy deposition into materials can induce unique nonequilibrium phases with distinct structures, chemistry, energetics, and properties. Mechanochemical synthesis and ion beam irradiation are two processing techniques that provide access to phases and states far from equilibrium. By a combination of high temperature oxide melt solution calorimetry, differential scanning calorimetry (DSC), neutron pair distribution function (PDF) analysis, and supplementary powder X-ray diffraction (XRD), the energetics and multiscale structural evolution on annealing of ball milled and swift heavy ion irradiated Er2Ti2O7 pyrochlore were investigated. Despite very similar structural modifications of local atomic arrangements and only minor differences in the long range structure, both types of damage yield significant difference in the energetics of the produced material. The energy of destabilization in the milled sample (70.2 ± 8.2 kJ/mol) is much less endothermic than that in the irradiated sample (457.3 ± 8.0 kJ/mol). The DSC profiles, supported by neutron scattering, X-ray diffraction, and solution calorimetry, reveal decoupled annealing events in different temperature ranges, separating crystallization of long range pyrochlore structure from annealing of short range weberite-like domains.

U–Si intermetallic compounds have drawn great attention due to their potential application as nuclear fuels. However, the thermodynamic properties and phase equilibria of this binary system from ambient to high temperature conditions are not fully understood. Via high temperature oxidative drop calorimetry and detailed characterization of the initial and final phases, we have experimentally determined the standard enthalpies of formation of USi and U3Si5.07 at 298 K to be −43.2 ± 6.2 and −43.8 ± 9.0 kJ/mol·atom, respectively. The energetics of the tetragonal USi (t-USi, space group I4/mmm) phase has also been calculated with Density Functional Theory (DFT) for the first time. Combining the obtained formation enthalpies with the heat capacities measured previously, we assessed the thermodynamic stability of t-USi relative to a phase assemblage of two other U–Si phases, U3Si5.07 and U3Si2, from ambient temperature to 1200 K. The tetragonal USi is thermodynamically more stable than U3Si5.07 + U3Si2, which supports previously published phase diagram (H. Okamoto and T. Massalski, 1990 [1]): specifically, at least one stable USi phase exists when the U content is 50 at.%. Further thermodynamic and phase equilibrium studies are needed for a more comprehensive understanding of the U–Si system across broader compositional and temperature ranges.

Background: Benzotriazoles (BTRs) and benzothiazoles (BTHs) are emerging contaminants with high production volume worldwide, which exhibit potential health risk to human. To date, little is known about the exposure of BTRs and BTHs (BTs) on human, especially in the context of pregnancy. Objectives: We aimed to characterize the exposure profiles, temporal variability, and potential predictors of urinary BTs during pregnancy. Methods: Between 2014 and 2015, we recruited 856 pregnant women in Wuhan who provided urine samples at three trimesters (13.1 ± 1.1, 23.7 ± 3.2, and 35.7 ± 3.4 gestational weeks). We measured the urinary concentrations of five BTRs (1‑H‑benzotriazole, 1‑hydroxy‑benzotriazole, xylyltriazole, tolyltriazole, 5‑chloro‑1‑H‑benzotriazole) and five BTHs (benzothiazole, 2‑hydroxy‑benzothiazole, 2‑methylthio‑benzothiazole, 2‑amino‑benzothiazole, 2‑thiocyanomethylthio‑benzothiazole) to characterize the exposure profiles of BTs. We calculated the intra-class correlation coefficients (ICCs) to assess the temporal variability and investigated potential predictors of urinary BTs by using the mixed models. Results: Most of the targeted BTs were detected in over 50% of urine samples, except for 5‑chloro‑1‑H‑benzotriazole (9.3%) and 2‑thiocyanomethylthio-benzothiazole (1.4%). The predominant BTRs in urine was 1‑hydroxy‑benzotriazole [Geometric Mean (GM): 0.77 ng/mL]. Benzothiazole was the major derivative in urine samples with a GM concentration of 1.6 ng/mL. Correlations among BTHs (r = 0.04–0.39) were higher than that among BTRs (r = 0.02–0.14). The exposure pattern was constant at low level and co-exposure to all the targeted compounds was infrequent during pregnancy. Urinary concentrations of BTRs exhibited considerable within-subject variation (ICCs: 0.12–0.56) during pregnancy. Relatively high temporal reliability was observed for urinary concentrations of BTHs with ICCs ranging from 0.42 to 0.85. It was found that parity, household income, pregnancy occupational status, sampling season and menstrual cycle were associated with urinary concentrations of BTs in pregnant women (P

Thermodynamics and annealing behavior of swift heavy ion amorphized Dy2Sn2O7 pyrochlore were studied. Its amorphization enthalpy, defined as the total energetic difference between the irradiation amorphized and undamaged Dy2Sn2O7 states, was determined to be 283.6 ± 6.5 kJ/mol by high temperature oxide melt drop solution calorimetry. It has been an enigma that stannate and some other pyrochlores do not follow the general rA/rB−radiation resistance relation seen in most pyrochlore systems. In this work, we use the amorphization enthalpy, which reflects all the complex chemical and structural characteristics, as a more effective parameter to correlate the radiation damage resistance of pyrochlores with their compositions. It successfully explains the superior radiation damage resistance of the stannate pyrochlores compared with titanate pyrochlores. Differential scanning calorimetry (DSC) reveals a strong exothermic event starting at 978 K, which is attributed to long-range recrystallization based on X-ray diffraction (XRD) analysis, similar to the effect previously observed in Dy2Ti2O7. A second pronounced heat event beginning at ∼1148 K, which results from local structural rearrangement, is clearly decoupled from the first event for irradiated Dy2Sn2O7. Both the heat releases measured by DSC on heating to 1023 and 1473 K, and the excess enthalpies of the annealed samples indicate that the recovery to the original, ordered state was not fully achieved up to even 1473 K, despite XRD showing the apparent restoration of crystalline pyrochlore structure. The remaining metastability may be attributed to local disorder in the form of weberite-like short-range domains in the recrystallized material. Intriguingly, the second event for different pyrochlores generally starts at similar temperatures while the onset of the long range recrystallization is compositionally dependent. The amorphization and thermal annealing behavior observed in irradiated Dy2Sn2O7 may provide insights into the general mechanisms of radiation damage and recovery of pyrochlores relevant to their nuclear applications.

Utilizing a combined approach of high temperature calorimetry and neutron total scattering, we obtained critical insights into the energetics and annealing of radiation damage in swift heavy ion irradiated Dy2Ti2O7 pyrochlore. Oxide melt solution calorimetry reveals that the radiation amorphized Dy2Ti2O7 is destabilized by 243 kJ/mol compared to fully ordered, crystalline pyrochlore. Differential scanning calorimetry of the amorphized sample shows a rapid exothermic event starting at 1063 K, which, based on neutron structural analysis, is related to recrystallization. The heat release on annealing to 1473 K, –137 kJ/mol, is only about half of the total energetic difference between the ordered crystalline and amorphized samples, despite the apparent recovery of long-range pyrochlore-like ordering. Detailed neutron structural analysis confirms the persistence of residual damage in the 1473 K annealed sample. This metastability is attributed to local disorder in the form of weberite-like short-range domains in the recrystallized material. The annealing of radiation damage appears to be a complex, multistep process with decoupled short- and long-range damage recovery. Heating well above the initial recrystallization temperature does not erase all the damage, which may have important implications for the use of pyrochlores as nuclear waste forms.

The oxidation resistance of two important surface finishes, electroless Ni/immersion Au (ENIG) and electroless Ni/electroless Pd/immersion Au (ENEPIG), is studied. Auger electron spectroscopy and X-ray photoelectron spectroscopy analyses show that ENEPIG is more oxidation resistant. The oxidized species of Ni diffuse through the Au grain boundaries. The mechanism for this better performance is that the Pd layer has an amorphous structure. The amorphous Pd layer is able to inhibit the out-diffusion of Ni atoms through high-diffusivity paths.

The preferred orientation growth of intermetallic compounds is becoming an increasingly important issue, due to recent advances in three-dimensional integrated circuits. This study reveals that Cu6Sn5 that is formed on Ni does not grow in random orientations, but exhibits a pronounced preferred orientation relationship. This relationship is identified as ( 1 2 ¯ 0 ) ( Cu,Ni ) 6 Sn 5 ( 1 1 ¯ 1 ) Ni and [ 0 0 1 ] ( Cu,Ni ) 6 Sn 5 [ 1 1 0 ] Ni , according to electron backscatter diffraction and high-resolution transmission electron microscopy analysis. One critical implication is that no Ni3Sn4 exists between Cu6Sn5 and Ni because the Cu6Sn5/Ni interface is coherent.

We report a case of oncocytic carcinoma arising in submandibular gland. The tumour occurred in the left submandibular gland of an 82-year-old Japanese man. Histologically, the tumour was mostly composed of large cells with eosinophilic granules in the cytoplasm and they were arranged in the solid sheets, islands with duct-like structure and cords. The tumour cells had aggressively invaded muscles and perineural tissues, and cervical lymphatic metastasis was frequently observed. Histochemically, the tumour cells were strongly positive for phosphotungstic acid-hematoxylin (PTAH) stain, and we diagnosed this malignant tumour as oncocytic carcinoma. Immunohistochemically, the tumour cells reacted positively for cytokeratin 7, 8, 19, epithelial membrane antigen (EMA), alpha-1-antichymotrypsin and carcinoembryonic antigen (CEA), but negative for cytokeratin 13, 14, smooth muscle actin (HHF35) and S-100 protein (S-100). Tumour was diagnosed as oncocytic carcinoma in submandibular gland. Its characteristics are discussed in term of its histopathological and immunohistochemical features.

Germ cell nuclear factor (GCNF), an orphan nuclear receptor, is essential for mouse embryogenesis. GCNF specifically binds to a DR0 response element via its DNA binding domain (DBD) in vitro and functions as a repressor of gene transcription. To further study the role of GCNF during embryogenesis, we have employed a Cre/loxP strategy and generated a line of GCNF mutant mice (GCNF(lox/lox)) in which the 243-base pair DBD-encoding exon has been deleted in the germline. However, the ligand binding domain (LBD) of GCNF is still expressed at the mRNA and protein levels in the GCNF(lox/lox) mice. GCNF(lox/lox) mice die at 9.5-10.5 days postcoitum. The tailbuds of these mutant embryos protrude outside the yolk sac. Expression of Oct-4 in the somatic cells of GCNF(lox/lox) embryos at 8.25 days postcoitum was not silenced as in the GCNF(+/+) embryos. Therefore, GCNF(lox/lox) mice phenocopy the GCNF(-/-) mice. Our results indicate that the DBD is essential for the function of GCNF during early mouse embryogenesis, and that the LBD does not mediate any function independent of the DBD at this stage of embryonic development. Our results also suggest that GCNF is indeed a transcriptional factor that represses gene transcription mediated via its DBD.

We report here complete coding sequences for the Uca pugilator homologs of the ecdysteroid (UpEcR) and retinoid-X receptors (UpRXR). Library screenings recovered cDNA clones containing a unique amino terminal open-reading frame (A/B domain) for each gene, most similar to insect B1 EcR and USP1/RXR isoforms. Splicing variants in the UpRXR ligand-binding domain were also identified, in a region critical for folding of Drosophila and lepidopteran USP. UpEcR and UpRXR proteins were able to associate, and both are required for binding to an ecdysteroid HRE; these interactions were not hormone-dependent. Ribonuclease protection assays (RPA) were conducted using A/B domain and ‘common’ (C or E) domain probes on RNA isolated from various stages of regenerating limb buds and ovaries. For several of the limb bud and ovarian stages examined, the relative level of A/B domain sequence protected was significantly less than common domain suggesting alternative amino terminal isoforms other than those isolated through cloning. This is the first report of UpEcR and UpRXR transcription during ovarian maturation, implicating the ovary as a potential target for hormonal control in Crustacea.

Germ cell nuclear factor (GCNF) is an orphan nuclear receptor for which a ligand has yet to be identified. However, we do know that GCNF binds to a novel response element as a homodimer and regulates expression of genes, such as the protamines, through this element. In the absence of a ligand, GCNF is a transcriptional repressor that interacts with co-repressors. During embryonic development, GCNF is expressed between the gastrula and neurula stages. Loss of GCNF causes embryonic lethality, disrupts normal somitogenesis, as well as neural tube and axis formation, suggesting that GCNF is a critical factor for normal embryonic development. In adult vertebrates, GCNF expression is predominantly found in the germ cells of gonads. GCNF expression in germ cells suggests that understanding its function in adults will yield greater insight into the regulation of gametogenesis, leading to new contraceptive targets.

The POU-domain transcription factor Oct4 is essential for the maintenance of the mammalian germline. In this study, we show that the germ cell nuclear factor (GCNF), an orphan nuclear receptor, represses Oct4 gene activity by specifically binding within the proximal promoter. GCNF expression inversely correlates with Oct4 expression in differentiating embryonal cells. GCNF overexpression in embryonal cells represses Oct4 gene and transgene activities, and we establish a link to transcriptional corepressors mediating repression by GCNF. In GCNF-deficient mouse embryos, Oct4 expression is no longer restricted to the germ cell lineage after gastrulation. Our studies suggest that GCNF is critical in repressing Oct4 gene activity as pluripotent stem cells differentiate and in confining Oct4 expression to the germline.

In the fiddler crab, Uca pugilator, we have investigated the temporal expression of receptors in various tissues using probes that encode Uca ecdysteroid receptor ( UpEcR ) and retinoid-X-receptor ( UpRXR ) gene homologs. During molt stages C 4 through D 1–4 , UpEcR and UpRXR transcripts are expressed in regenerating limb buds, gills, eyestalks, hypodermis, hepatopancreas, muscle from nonregenerating walking legs, and the large cheliped. Some of these tissues have not previously been recognized as ecdysteroid-target tissues. Levels of ecdysteroids in the hemolymph fluctuate significantly during the molt cycle of U. pugilator. The variation in steady-state concentrations of UpEcR transcripts in tissues from C 4 to D 1–4 implies molt cycle-related differences in the potential of these tissues to respond to changing titers of ecdysteroids in the hemolymph. In singly autotomized crabs, highest concentrations of UpEcR transcript in some tissues did not coincide with the highest levels of circulating ecdysteroids, suggesting that UpEcR expression in these tissues is not dependent on high ecdysteroid titers and may be induced by low or rising concentrations of ecdysteroids. UpEcR and UpRXR genes were expressed simultaneously in tissues, supporting the possibility of heterodimerization for EcR and RXR in vivo. In some tissues, however, levels of transcripts differed, suggesting other possible receptor interactions. Moreover, UpEcR expression in tissues from multiply autotomized crabs differed from the expression patterns in tissues from singly autotomized crabs.

(Pyrrolidine)- and (piperidine)acetates are efficiently synthesized via radical cyclization of β-aminoacrylates.

The effects of depositional environment on properties, stress history, and undrained and drained shear-strength parameters are evaluated for Chicago glacial clay. Recent geology and basic depositional environments are described. Both laboratory and in-situ shear-strength evaluations have been conducted at several sites in the study area. Results of the investigations indicate that, while depositional environment has a large impact on the engineering properties of these clays, identification of the depositional environment is in itself insufficient to strength parameters. Post-depositional events are shown to alter the stress history imparted during deposition and thus impact shear-strength parameters.

N-Aryl-N-(3-bromopropyl)amides are converted to N-(3-arylpropyl)amides under standard radical generating conditions via intramolecular ipso attack of the alkyl radicals which generates spiro cyclohexadienyl radical intermediates.