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Ultrarefractory (UR) condensates found in refractory inclusions in chondrites contain records of the early nebular thermochemistry that prevailed in the high-temperature region close to the protosun. Recent reports of the UR phases such as allendeite (Sc 4 Zr 3 O 12), tazheranite ((Zr,Ti,Ca)O 2−x), and kangite ((Sc,Ti,Al,Zr,Mg,Ca,□) 2 O 3) imply, respectively, nebular condensation temperatures and origins higher than and inward of those previously deduced from calcium-aluminum-rich inclusions. However, knowledge gaps on their thermochemistry have precluded a quantitative understanding of temperatures and chemical pathways that led to their origins in the early solar protoplanetary disk. Here we use density functional theory to determine the thermochemistry of these materials for the first time. We find that allendeite is a stable phase under equilibrium conditions with its condensation temperature (1643 K at 10−4 bar) in the same range as that of nominal hibonite (CaAl 12 O 19 , 1637 K at 10−4 bar). Among the UR oxides, tetragonal ZrO 2 exhibits the highest condensation temperature (1739 K at 10−4 bar) and potentially reveals the high-temperature limits at which solid dust could have survived in the inner region of the disk. In comparison, we find that pure cubic ZrO 2 does not form from a cooling gas of solar composition undergoing equilibrium condensation. Similarly, we find that the stoichiometric endmember of kangite, Sc 2 O 3 does not condense under equilibrium conditions, and moreover, the role of Ti and Zr as solutes is crucial to modeling its stability and origins. [ABSTRACT FROM AUTHOR]

Neurotransmitters play an important role in larval metamorphosis in different groups of marine invertebrates. In this work, the role of dopamine and serotonin during metamorphosis of the ascidian Phallusia mammillata larvae was examined. By immunofluorescence experiments, dopamine was localized in some neurons of the central nervous system and in the adhesive papillae of the larvae. Dopamine and serotonin signaling was inhibited by means of antagonists of these neurotransmitters receptors (R(+)-SCH-23390, a [D.sub.1] antagonist; clozapine, a [D.sub.4] antagonist; WAY-100635, a 5-H[T.sub.1A] antagonist) and by sequestering the neurotransmitters with specific antibodies. Moreover, dopamine synthesis was inhibited by exposing 2-cell embryos to a-methyl-L-tyrosine. Dopamine depletion, obtained by these different approaches, caused early metamorphosis, while serotonin depletion delayed the onset of metamorphosis. The opposite effects were obtained using agonists of the neurotransmitters: lisuride, a [D.sub.2] agonist, inhibited metamorphosis, while DOI hydrochloride and 8-OH-DPAT HBr, two serotonin agonists, promoted it. So, it is possible to suppose that dopamine signaling delayed metamorphosis while serotonin signaling triggers it. We propose a mechanism by which these neurotransmitters may modulate the timing of metamorphosis in larvae. Keywords: Neurotransmitter; Urochordata; Ascidian metamorphosis; Larval development; Nervous system

The valorization of secondary sands is crucial for fostering a circular economy within the construction sector. One significant obstacle in this endeavor stems from the high water absorption (WA) rates commonly reported for secondary sands. This high WA leads to increased water and cement demand in cementitious mixes and elevates costs. The only widely standardized method to measure the WA of fine aggregates is the cone method, which has proven ill-suited for fine aggregates with angular particles or a high content of fines. This study undertakes a comparative evaluation of the cone method and seven alternative methods: immersion, centrifugation, paper sheet, colorimetric, volumetric flask, continuous drying, and electrical conductivity. Tests were performed on natural river sand and three types of secondary sand. Findings reveal that the continuous drying and electrical conductivity methods demonstrates the greatest potential in terms of reliability and applicability. Also the volumetric flask and centrifugation methods show some potential, provided that critical refinements are made to the corresponding test protocols. • Flaws of water absorption methods for secondary sands are exposed. • Caution should be taken in the interpretation of water absorption data from the literature. • There is an urgent need for improved water absorption assessment of secondary sands. • Electrical conductivity and continuous drying methods are recommended. [ABSTRACT FROM AUTHOR]

Sulfide minerals occur in many types of extraterrestrial samples and are sensitive indicators of the conditions under which they formed or were subsequently altered. Here we report that chemical and petrographic analyses of Fe,Ni sulfides can be used to determine the metamorphic type of the host LL chondrite, and constrain their alteration conditions. Our data show that the major- and minor-element compositions of the pyrrhotite-group sulfides (dominantly troilite) and pentlandite vary with degree of thermal metamorphism experienced by their host chondrite. We find that Fe,Ni sulfides in LL3 chondrites formed during chondrule cooling prior to accretion, whereas those in LL4 to LL6 chondrites formed during cooling after thermal metamorphism in the parent body, in agreement with previous work. High degrees of shock (i.e., ≥S5) caused distinct textural, structural, and compositional changes that can be used to identify highly shocked samples. Distinct pyrrhotite-pentlandite textures and minerals present in Appley Bridge (LL6) suggest that they cooled more slowly and therefore occurred at greater depth(s) in the host parent body than those of the other metamorphosed LL chondrites studied here. Sulfides in all LL chondrites studied formed under similar sulfur fugacities, and the metamorphosed LL chondrites formed under similar oxygen fugacities. The data reported here can be applied to the study of other LL chondrites and to sulfides in samples of asteroid Itokawa returned by the Hayabusa mission in order to learn more about the formation and alteration history of the LL chondrite parent body. [ABSTRACT FROM AUTHOR]

Micro-Electro-Mechanical Systems (MEMS) gyroscopes are inertial sensors for the measurement of angular rates. They have a variety of applications from consumer electronics to drones and the need of stability against environmental fluctuations, such as temperature, is a key factor in order to avoid expensive calibration procedures. Frequency Modulation (FM) has been recently proposed as an innovative working principle for MEMS gyroscopes and as the desired solution in terms of stability against environmental fluctuations. In this paper, the FM working principle is formalized for the three-axial case for the first time and the governing equations are derived both in the idealized case of a point-mass gyroscope and in the real case of a distributed-mass gyroscope. Moreover, the mechanical structure of the first three-axial MEMS FM gyroscope is proposed and studied. Preliminary experimental measurements prove the validity of both the model and the simulations results employed during the design process. The proposed structure overcomes lots of the constraints of the surface micromachining fabrication processes and represents an important step towards the development of a new class of MEMS gyroscopes. [ABSTRACT FROM AUTHOR]

Rural houses are recently built using confined masonry walls. The concrete beam and column confining the wall are usually considered to resist lateral loads, such as earthquake load. The Indonesian code requires reinforcement of 12 mm diameter in each corner of the beam and column with 8 mm diameter of stirrups. Such houses are usually termed of non-engineered structures, i.e buildings which the strength is not technically calculated but is established by the communities based on their experiences. This research was aimed to relate the in plane lateral ground acceleration and the resulting lateral displacement on the top of the wall at the first fundamental frequency. As the wall occasionally breaks at certain lateral drift ratio (H/V ratio), therefore, a prediction of the maximum lateral ground acceleration of the wall due to earthquake shake may also be established. Two wall specimens were made of local masonries with dimensions of 3m x 3m and 0.15 m thick. Lateral loads were applied in several stages and ambient vibrations of the two accelerometers, mounted on the base and on the top of the wall, were also recorded in stages. The maximum lateral force prediction, calculated using allowable lateral ground acceleration, was closely approaching the experiment result and numerical calculation. [ABSTRACT FROM AUTHOR]

The dynamic behavior of a torsional microresonator is characterized analytically, numerically and experimentally both in the linear and nonlinear regime. Starting from the work presented in [1] , here, the highly nonlinear regime is considered and the dynamic pull-in is experienced. Very good agreement between experimental data and numerical model is found also when the analytical methods usually employed to describe the nonlinear dynamic behavior of MEMS (multiple scale methods) are no more accurate. Finally, a numerical limit domain for the microresonator safe operation region in terms of bias and actuation voltages is computed and validated with experimental data. [ABSTRACT FROM AUTHOR]

Pectin methyl esterase ( PME ) genes code for enzymes that are involved in structural modifications of the plant cell wall during plant growth and development. They are also involved in plant-pathogen interaction. PME genes belong to a multigene family and in this study we report the first comprehensive analysis of the PME gene family in bread wheat ( Triticum aestivum L.). Like in other species, the members of the TaPME family are dispersed throughout the genome and their encoded products retain the typical structural features of PMEs. qRT-PCR analysis showed variation in the expression pattern of TaPME genes in different tissues and revealed that these genes are mainly expressed in flowering spikes. In our attempt to identify putative TaPME genes involved in wheat defense, we revealed a strong variation in the expression of the TaPME following Fusarium graminearum infection, the causal agent of Fusarium head blight (FHB). Particularly interesting was the finding that the expression profile of some PME genes was markedly different between the FHB-resistant wheat cultivar Sumai3 and the FHB-susceptible cultivar Bobwhite, suggesting a possible involvement of these PME genes in FHB resistance. Moreover, the expression analysis of the TaPME genes during F. graminearum progression within the spike revealed those genes that responded more promptly to pathogen invasion. [ABSTRACT FROM AUTHOR]

For the development of an intermediate radioactive waste repository, two different types of reinforced concrete were analyzed in terms of durability: one made with ordinary portland cement and the other one made with pozzolanic cement. The values for compressive strength, sorptivity and air permeability demonstrate that the formulations are compatible with the required application. The corrosion rate of rebar up to about 300 days of monitoring and obtained with sensors is below the threshold value required for this type of facilities, except when temperatures are high. The value for the same parameter monitored by the galvanostatic pulse technique using superficial counter electrode and guard electrode is always lower than the threshold value. Additionally, when applying the galvanostatic pulse technique using embedded electrodes, this parameter is comparable to the guard electrode method only when the polarization resistance is calculated through non-linear fitting. [ABSTRACT FROM AUTHOR]

This paper reports the theoretical and experimental characterization of a new z-axis silicon resonant micro accelerometer fabricated by the THELMA © surface micromachining technique, characterized by differential sensing and very small dimensions. The working principle of this device is based on the variation of the electrostatic stiffness of two torsional resonators. This work is a prosecution of the research on resonant accelerometers published in [1,2] . [ABSTRACT FROM AUTHOR]

The microstructures and chemistry of secondary feldspars and phosphates in equilibrated ordinary chondrites (OCs) suggest that fluids were involved in the formation of these phases, challenging the conventional view that secondary alteration of equilibrated OCs occur under water-absent conditions. The newly discovered Sidi El Habib 001 (SEH 001), a halite-bearing H5 OC, provides a unique opportunity to further probe the role of fluids during thermal metamorphism on the OC parent bodies. Here we report a petrographic and mineralogic study of SEH 001, with the aim of understanding the origins of halite grains and their implications for the alteration histories of equilibrated OCs. Our investigation reveals a main halite-bearing lithology and a halite-free lithology, both of which show equilibrated textures. Except for halides, no significant textural or compositional differences were observed between halite-bearing and -free lithologies. Halite occurs at all spatial scales in the main lithology and shows clear textures of replacing albitic plagioclase and Cl-apatite. Chlorapatite grains in SEH 001 are Cl-rich and many of them contain elevated amounts of "other" anions. Our observations suggest that halite grains in SEH 001 formed in situ on the parent body via precipitation from an aqueous fluid. The replacement of plagioclase and Cl-apatite by halite and the equilibrated textures of halite-bearing and halite-free lithologies point to a hydrothermal alteration history where halite formed during advanced thermal metamorphism before the fluid was completely lost. The two lithologies were likely affected by fluids with different Cl concentrations that resulted from heterogeneous distribution of HCl hydrate. Based on comparison to experimental data, halite in SEH 001 could have survived peak metamorphism because of its relatively high thermal stability. Collisional disruption of its original parent body could also facilitate the preservation of halite via release of heat. In the rubble pile model of the OC parent body formation, subsequent accretion of hot fragments into a rubble pile body could have resulted in the blurred boundaries between halite-free and -bearing lithologies now observed in our sample. The occurrence of halite in SEH 001 is clear evidence that aqueous fluids were involved in the alteration of equilibrated OCs. Combined with previous reports of hydrous minerals (such as phyllosilicates) and other related aqueous products in unequilibrated OCs, our study further suggests that S-type asteroids, the parent bodies of OCs, could be more hydrated than previously thought and might serve as a potential source of water for terrestrial planets in the inner solar system. Nevertheless, whether the proposed hydrothermal history of SEH 001 can be extrapolated to other equilibrated OCs needs to be tested. The in-situ formation origin of halite in SEH 001 contrasts with the exogeneous origin of halite in Monahans (1998) and Zag, suggesting that halites with different origins occurred on the OC parent bodies. The rarity of halite in OCs could be attributed to the heterogeneous distribution of HCl hydrate in the OC parent bodies, although the fragile nature of halite in terrestrial and laboratory environments also increases the likelihood of halite being destroyed in OC samples. [ABSTRACT FROM AUTHOR]

Abstract: We report on the isotopic and microstructural properties of four presolar spinel grains identified in acid-resistant residues of the Murray CM2 and Orgueil (ORG) CI1 chondrites, and a mixture of the unequilibrated ordinary chondrites (UOC) QUE 97008 (L3.05), WSG 95300 (H3.3), and MET00452 (LL3.05) collected in Antarctica. All four grains have O-isotopic compositions indicating an origin in low-mass (∼1.2–1.4M⊙) O-rich asymptotic giant branch (AGB) stars, although two of the grains have compositions indicating that non-standard mixing (cool-bottom processing) likely occurred in their parent stars. Three of the grains are single-crystal Mg–Al-rich spinels containing minor Fe and Cr; one is Mg deficient and one contains minor Ca. The fourth consists of an assemblage of three, Fe–Cr-rich crystalline grains with closely aligned crystallographic orientation but systematically varied cation composition. Each spinel grain within the assemblage also contains Ti-rich sub-grains (<100nm) whose lattice structures are coherent with their host crystals. Oxygen isotope measurements of the Orgueil residue identified four additional particles all with similar elemental and isotope composition. These are the first known presolar Fe–Cr-rich spinels. The isotopic and microstructural data indicate that the Al–Mg-rich and Fe–Cr-rich grains experienced different condensation and processing histories. The single-crystal, stoichiometric, nearly pure Mg–Al spinels are generally consistent with equilibrium condensation predictions, which constrain their condensation temperatures between 1161 and 1221K, assuming total gas pressures of 1×10−6 and 1×10−3 atm, respectively. Minor stacking disorder is observed in one of the Mg–Al spinels and is probably a result of slight perturbations to crystal growth during condensation in the circumstellar environment or of impact-induced sheer strain as a response to grain-grain collisions, which could have occurred in the circumstellar environment, the interstellar medium, or the solar nebula. The minor Ca in one of the Mg–Al spinels suggests back reaction with the circumstellar gas from which it formed. In comparison, the similarly oriented Fe–Cr-rich grains of the Orgueil assemblage and their homogeneous isotopic compositions are consistent with their condensation as a single circumstellar dust particle. However, the Fe–Cr-rich compositions (nearly chromite) are inconsistent with predictions for equilibrium condensation and suggest a complex cooling history that is not possible to precisely constrain. [Copyright &y& Elsevier]

Abstract: The use of construction waste materials as aggregates for concrete production is highly attractive compared to the use of non-renewable natural resources, promoting environmental protection and allowing the development of a new raw material. Several countries have recommendations for the use of recycled coarse aggregate in structural concrete, whereas the use of the fine fraction is limited because it may produce significant changes in some properties of concrete. However, during the last decade the use of recycled fine aggregates (RFA) has achieved a great international interest, mainly because of economic implications related to the shortage of natural sands suitable for the production of concrete, besides to allow an integral use of this type of waste. In this study, the durable behaviour of structural concretes made with different percentage of RFA (0%, 20%, and 30%) is evaluated. Different properties related to the durability of concretes such as absorption, sorptivity, water penetration under pressure, and carbonation are determined. In addition, the results of compressive strength, static modulus of elasticity and drying shrinkage are presented. The obtained results indicate that the recycled concretes have a suitable resistant and durable behaviour, according to the limits indicated by different international codes for structural concrete. [Copyright &y& Elsevier]

Abstract: The discovery of nickel-, copper-, and zinc-bearing iron sulfides from comet 81P/Wild 2 (Wild 2) represents the strongest evidence, in the Stardust collection, of grains that formed in an aqueous environment. We investigated three microtomed TEM sections which contain crystalline sulfide assemblages from Wild 2 and twelve thin sections of the hydrothermally altered CI chondrite Orgueil. Detailed structural and compositional characterizations of the sulfide grains from both collections reveal striking similarities. The Stardust samples include a cubanite (CuFe2S3) grain, a pyrrhotite [(Fe,Ni)1− x S]/pentlandite [(Fe,Ni)9S8] assemblage, and a pyrrhotite/sphalerite [(Fe,Zn)S] assemblage. Similarly, the CI-chondrite sulfides include individual cubanite and pyrrhotite grains, cubanite/pyrrhotite assemblages, pyrrhotite/pentlandite assemblages, as well as possible sphalerite inclusions within pyrrhotite grains. The cubanite is the low temperature orthorhombic form, which constrains temperature to a maximum of 210°C. The Stardust and Orgueil pyrrhotites are the 4C monoclinic polytype, which is not stable above ∼250°C. The combinations of cubanite and pyrrhotite, as well as pyrrhotite and pentlandite signify even lower temperatures. The crystal structures, compositions, and petrographic relationships of these sulfides constrain formation and alteration conditions. Taken together, these constraints attest to low-temperature hydrothermal processing. Our analyses of these minerals provide constraints on large scale issues such as: heat sources in the comet-forming region; aqueous activity on cometary bodies; and the extent and mechanisms of radial mixing of material in the early nebula. The sulfides in the Wild 2 collection are most likely the products of low-temperature aqueous alteration. They provide evidence of radial mixing of material (e.g. cubanite, troilite) from the inner solar system to the comet-forming region and possible secondary aqueous processing on the cometary body. [Copyright &y& Elsevier]

Abstract: We report a coordinated analytical study of matrix material in the Tagish Lake carbonaceous chondrite in which the same small (⩽20μm) fragments were measured by secondary ion mass spectrometry (SIMS), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), electron energy-loss spectroscopy (EELS), and X-ray absorption near-edge spectroscopy (XANES). SIMS analysis reveals H and N isotopic anomalies (hotspots), ranging from hundreds to thousands of nanometers in size, which are present throughout the fragments. Although the differences in spatial resolution of the SIMS techniques we have used introduce some uncertainty into the exact location of the hotspots, in general, the H and N isotopic anomalies are spatially correlated with C enrichments, suggesting an organic carrier. TEM analysis, enabled by site-specific extraction using a focused-ion-beam scanning-electron microscope, shows that the hotspots contain an amorphous component, Fe–Ni sulfides, serpentine, and mixed-cation carbonates. TEM imaging reveals that the amorphous component occurs in solid and porous forms, EDS indicates that it contains abundant C, and EELS and XANES at the C K edge reveal that it is largely aromatic. This amorphous component is probably macromolecular C, likely the carrier of the isotopic anomalies, and similar to the material extracted from bulk samples as insoluble organic matter. However, given the large sizes of some of the hotspots, the disparity in spatial resolution among the various techniques employed in our study, and the phases with which they are associated, we cannot entirely rule out that some of the isotopic anomalies are carried by inorganic material, e.g., sheet silicates. The isotopic composition of the organic matter points to an initially primitive origin, quite possibly within cold interstellar clouds or the outer reaches of the solar protoplanetary disk. The association of organic material with secondary phases, e.g., serpentine and carbonates, suggests that the organic matter was susceptible to parent-body processing, and thus, isotopic dilution. [Copyright &y& Elsevier]

Abstract: Paraquat is an herbicide widely used in agriculture, that proved to have toxic effect on many animal models. Moreover, it is considered a potential etiologic factor of Parkinson''s disease. Ascidians are invertebrate chordates, whose larval central nervous system shares basic structural homologies with the vertebrate one. Ascidian larvae exposed to paraquat developed specific alterations of the CNS, that were characterized by histological and immunohistochemical analysis. Tyrosine hydroxylase (TH) expression was examined by “in situ” hybridization. A decrease of dopamine content in anterior CNS of treated larvae was observed. In combined treatments with paraquat and l-ascorbic acid, a common anti-oxidant, the severity of the malformations was significantly reduced, confirming that the oxidative stress is involved in the toxicity mechanism of paraquat on ascidians. For its sensitivity to paraquat and its simple chordate body plan, ascidian larva is a promising animal model to further investigate the molecular mechanism of paraquat neurotoxicity. [Copyright &y& Elsevier]

Abstract: Imazalil (IMA) is a fungicide that is used extensively in fruit plantations and post-harvest treatments, but has teratogenic effects on vertebrate development, possibly due to the perturbation of retinoic acid (RA) levels in the embryo. Ascidians are sessile marine invertebrate chordates that develop through a tadpole larva, with a body plan that shares basic homologies with vertebrates. In this work, we tested the effects of IMA on the development of the solitary ascidian Ciona intestinalis by treating two-cell stage embryos with a range of concentrations (0.1, 0.5, 1, 2.5, 5, 10, 20 and 50μM). The fungicide significantly altered ascidian development even at low concentrations and its effects were dose-dependent. Probit analysis revealed that the median lethal concentration, LC50, was 4.87μM and the median teratogenic concentration, TC50, was 0.73μM. Larvae developing from embryos exposed to IMA showed malformations of the anterior structures, which became more severe as IMA concentration increased. In particular, the anterior nervous system and the sensory vesicle were reduced, and the pigmented organs (the ocellus and the otolith) progressively lost their pigmentation. The larval phenotype induced by 5μM IMA exposure was further characterized by means of molecular analysis, through whole mount in situ hybridization with probes for genes related to the nervous system: Ci-Otp, Ci-GAD, Ci-POU IV, which are markers of the anterior neuro-ectoderm, the central nervous system and the peripheral nervous system respectively, and Ci-Hox-1, a gene specifically activated by RA, and Ci-Aldh2, a gene for aldehyde dehydrogenase, which is involved in RA synthesis. The altered expression of Ci-Otp, Ci-GAD, Ci-POU IV in 5μM IMA-exposed larvae compared to control larvae showed that this fungicide could affect the differentiation of the anterior nervous system, particularly of the sensory vesicle neurons. Recent studies suggest a similarity between IMA- and RA-induced phenotypes in tunicates, indicating that triazoles may also alter RA metabolism in ascidians. The observed Ci-Hox-1 and Ci-Aldh2 expression in control and treated larvae did not allow a direct link between IMA teratogenic potential and RA-dependent morphogenesis to be identified. It is likely that the fungicidal teratogenic mechanism involved RA signalling but that its effects on ascidian development depend on a more complex mechanism. [Copyright &y& Elsevier]

A series of azaphenylalanine derivatives were investigated as novel thrombin inhibitors based on the prodrug principle. By systematic structural modifications we have identified optimal groups for this series that led us to potent inhibitors of thrombin incorporating the benzamidine fragment at the P1 position, and their potentially orally active benzamidoxime prodrugs. The binding modes in the thrombin active site of two representative compounds were identified by X-ray crystallographic analysis. [Copyright &y& Elsevier]

A chrysotile-like phase, cronstedtite, polygonal serpentine, pentlandite, and finely intergrown tochilinite comprise the fine-grained rim (FGR) mineralogy of the Cold Bokkeveld CM chondrite. Transmission electron microscope images combined with compositional data indicate reaction among cronstedtite, the chrysotile-like phase, and polygonal serpentine. The Mg/(Mg+Fe) ratios of the cronstedtite are higher than those reported for the less altered Murchison CM chondrite. Cronstedtite grains exhibit layer separations, particularly at their boundaries.The FGRs surround different chondrule types but have similar bulk compositions and mineralogy. Ca is depleted in the FGRs relative to the bulk CM chondrite. The FGRs display non-uniform thicknesses, especially where they coat embayed chondrule areas, and they exhibit grain-size coarsening outward from the chondrules they enclose. FGR formation in Cold Bokkeveld is most plausibly explained by multiple accretionary episodes during which progressively coarser dust was deposited onto chondrules, presumably in the solar nebula. The compositional and mineralogic data are consistent with aqueous alteration on the parent body. [Copyright &y& Elsevier]

We report a comprehensive study of the ungrouped type 2 carbonaceous chondrite, Tarda, which fell in Morocco in 2020. This meteorite exhibits substantial similarities to Tagish Lake, Wisconsin Range 91600, and Meteorite Hills 00432, which are generally considered to have originated from a D-type asteroid(s). We constrain the compositions and petrologies of the materials present in a potential sample of a D-type asteroid by reporting the petrography, bulk chemical compositions, bulk H, C, N, Cr, and Ti isotopic compositions, reflectance spectra, and in situ chemical compositions of metals, sulfides, carbonates, and FeO-poor and FeO-rich chondrule silicates of Tarda. We also present new data for Tagish Lake. We then compare Tarda with the other Tagish Lake-like meteorites. Tarda and Tagish Lake appear to be from the same parent body, as demonstrated by their similar petrologies (modal abundances, chondrule sizes), mineral compositions, bulk chemical and isotopic compositions, and reflectance spectra. While the two other Tagish Lake-like meteorites, Wisconsin Range 91600 and Meteorite Hills 00432, show some affinities to Tagish Lake and Tarda, they also share similar characteristics to the Mighei-like carbonaceous (CM) chondrites, warranting further study. Similarities in reflectance spectra suggest that P-type asteroids 65 Cybele and 76 Freia are potential parent bodies of Tarda and the Tagish Lake-like meteorites, or at least have similar surface materials. Since upcoming spacecraft missions will spectrally survey D-type, P-type, and C-type Trojan asteroids (NASA's Lucy) and spectrally study and return samples from Mars' moon Phobos (JAXA's Martian Moons eXploration mission), which is spectrally similar to D-type asteroids, these meteorites are of substantial scientific interest. Furthermore, since Tarda closely spectrally matches P-type asteroids (but compositionally matches the D-type asteroid like Tagish Lake meteorite), P-type and D-type asteroids may represent fragments of the same or similar parent bodies. [ABSTRACT FROM AUTHOR]

A petrographic method is proposed to semi-quantify the content of particles with reactive phases in fine recycled concrete aggregates (FRCA) affected by the alkali-silica reaction and the residual mortar (RM) adhered to them. This method is compared to the image analysis method. Quartered FRCA samples are studied by three petrographers, and the results are compared. Finally, the potential reactivity of the samples is evaluated by the accelerated mortar bar test (AMBT). According to the AMBT and petrographic method, the samples are qualified as potentially reactive, with a low degree of reactivity. The method is easy to perform and fast (compared to image analysis), but the results obtained by three petrographers show some differences that can mainly be attributed to the visual estimation of RM. Although more studies are needed to verify the effectiveness of the proposed method, the implemented technique shows great potential to semi-quantify reactive components in FRCA particles. • A petrographic method to study fine recycled concrete aggregates (FRCA) is proposed. • Particles containing reactive components and residual mortar (RM) are semi-quantified. • FRCA particles have little or much adhered RM. • The RM content (wt%) decreases with the reduction of the FRCA size fraction. • Results of the AMBT and the petrographic method are consistent. [ABSTRACT FROM AUTHOR]

Abstract: Several amino sulfonylureas have been synthesized, starting from amino acids. The synthetic procedure is simple affording high yields of products under mild conditions. Furthermore, it is shown that these compounds can be incorporated into a peptide sequence. [Copyright &y& Elsevier]

Microsystems (or Micro Electro Mechanical Systems, MEMS) are important components of many popular products in the consumer market and are one of the enabling ingredients of incoming industrial revolutions like Industry 4.0 and Internet of Things (IoT). Behind many Microsystems there are important mechanical principles and coupling effects that must be completely mastered starting from the design phase. More sophisticated and smaller devices also imply to consider many non-linear effects that can be strictly related to the mechanical response or to coupled electro-thermo-mechanical phenomena. This paper contains an overview of key mechanical aspects in design and reliability of Microsystems with a particular focus on non-linear dynamics of oscillators in inertial sensors. • State of the art on non-linear mechanical phenomena in microsystems. • Focus of the paper on resonant inertial micro sensors. • Various examples on non-linearities in real cases. • Discussion on future research directions. [ABSTRACT FROM AUTHOR]

Calcium-aluminum-rich inclusions (CAIs) are the first formed solids in our solar system. Information regarding their formation and alteration is imprinted within their crystal structures, and so analysis of CAIs can provide insight into the early stages of solar system formation. Here we report on micrometer-sized metal grains that occur inside of fluffy type A (FTA) CAIs in the NWA 8323 and Leoville CV3 chondrites. Transmission electron microscopy (TEM) shows that the ultra-refractory metal assemblages contain subhedral grains of crystalline alloys of Pt, Os, Ir, Ru, Fe, Ni, and Mo, with minor amounts of oxides and silicates inclusions. These assemblages occur in melilite and are surrounded by or adjacent to spinel and perovskite. TEM analysis shows that the majority of the alloys present in the assemblages are significantly enriched in Pt-group elements, with compositions of 75 wt % Pt in some Fe-Ni-Pt grains, and >90 wt % Pt-group elements in Os-Ir-Ru grains. Electron diffraction shows that the alloys occur predominantly in a hexagonal (HCP) structure, with a minority of the grains exhibiting cubic (FCC) and tetragonal lattices. To support these findings, we present a thermodynamic model for the formation of hexagonal (HCP) and cubic (BCC and FCC) ultra-refractory alloys. We use an Fe-Os-Ir ternary system to approximate the various compositions and crystal structures observed in the metal grains. Modeling results indicate a condensation temperature for the alloys as high as 1831 K (HCP, 10−4 bar), placing them well above those predicted for the major CAI phases that surround them. Based on the spatial relationships of the refractory metal grains to their host CAIs, our thermodynamic predictions, and prevailing astrophysical models of the solar protoplanetary disk, the data imply that the grains could have formed inward of the regions where CAI materials condensed. We hypothesize that the refractory metal grains were transported radially outward to the part of the disk where CAIs formed and provided a nucleation site for the condensation of CAI phases such as melilite, hibonite, perovskite, and spinel. [ABSTRACT FROM AUTHOR]

The performance of cementitious materials made with Recycled Concrete Aggregates (RCA) and exposed to sulfate-laden environments is not yet fully understood. There are few studies on this topic, and for a full description of the mechanisms of external sulfate attack (ESA), several influencing parameters should be considered. The replacement of natural aggregates by RCA modifies the physical and chemical properties of the new material and introduces additional variables into the already complex mechanism. The high porosity of RCA contributes to accelerating the sulfate penetration from the surface, while the attached mortar increases the mineral supply that can react with the incoming sulfate. This paper describes a study on the performance of mortars made with RCA exposed to different ESA conditions. Design and exposure parameters include three cement, two specimen sizes, and two sulfate media (soil and solution). Visual inspection and measurements of expansion and weight change were used to determine the performance of the mixes. From a microstructural point of view, thermogravimetric analyses were carried out on samples obtained from the mortar bars after exposure. These results are then used to infer on the thermodynamic and kinetic aspects of ESA progression in recycled mortar. Finally, SEM/EDS analyses were also performed to further describe sulfate penetration and its relationship with cracking. The results show a limited influence of fine recycled aggregate on the mortar performance against ESA and no proportionality to its content. [ABSTRACT FROM AUTHOR]

Summary Introduction Descriptions of the penile prepuce in anatomical and clinical texts either omit details or contain a small, yet potentially serious, error with regard to the manner of its attachment to the penis. Objective This study sought to cast light on a ubiquitous but poorly understood and under-appreciated structure, while correcting a long-standing mistake in the medical literature. Study design The foreskins of five male stillborn babies were dissected and carefully examined. Tissue from the apposing surfaces of the various regions of the inner and outer prepuce surfaces and the transition zone itself were collected, embedded in paraffin, sectioned, stained, examined and photographed under microscopy. Results Contradicting the prevailing descriptions in the literature that the inner prepuce is a single, uniform sheath, this study's observations and histological findings demonstrated that it actually splits into separate laminae that connect distally to the shaft at the base of the corona and proximally with the shaft fascia, respectively ( Figure ). Discussion The penile prepuce is a discrete and deceptively complex part of the male anatomy, yet key details of its interposing surfaces are inaccurately described or entirely omitted in the literature. Understanding the normal anatomy of the prepuce is critically relevant, particularly for urologists and others involved in the performance of circumcision. For example, avoiding potentially catastrophic avulsion of the inner preputial remnant beyond the coronal sulcus during circumcision and accurate assessment of tissue positioning prior to penile reconstruction in cases of hypospadias. Conclusion The findings of this study correct a misunderstanding in the anatomy of the prepuce. [ABSTRACT FROM AUTHOR]

Micro-Electro-Mechanical Systems (MEMS) accelerometers are micro-sized devices largely used for detecting accelerations in the consumer and automotive market. Both capacitive and resonant sensing have been successfully employed in these devices. In the present work, the focus is on a z-axis resonant accelerometer recently proposed in [1] and fabricated with the Thelma © surface-micromachining technique developed by STMicroelectronics [2] . After a full non-linear dynamic study, two possible optimized designs are studied through an optimization procedure. The goal of the work is to find a novel design for the z-axis resonant accelerometer which meets the linearity and the reliability requirements for MEMS accelerometers whitout losses in terms of sensitivity. [ABSTRACT FROM AUTHOR]