Bachia heteropa

Number of Pages: 10Integrative BiologyGeological Science

Mn-phthalocyanine molecules adsorbed on superconducting Pb(111)

Magnetic molecules adsorbed on a superconductor give rise to a local competition of Cooper pair and Kondo singlet formation inducing subgap bound states. For manganese-phthalocyanine molecules on a Pb(111) substrate, scanning tunneling spectroscopy resolves pairs of subgap bound states and two Kondo screening channels. We show in a combined approach of scaling and numerical renormalization group calculations that the intriguing relation between Kondo screening and superconducting pairing is solely determined by the hybridization strength with the substrate. We demonstrate that an effective one-channel Anderson impurity model with a sizable particle-hole asymmetry captures universal and nonuniversal observations in the system quantitatively. The model parameters and disentanglement of the two screening channels are elucidated by scaling arguments

Multi-party certification on blockchain and its impact in the market for lemons

Markets in which similar goods of different qualities are sold suffer from information asymmetries and their negative consequences. Dealers have established themselves, and mediate these markets through their use of quality signals. While these signals help to mitigate information asymmetries, these markets still function well below their optimum: a large share of goods sold are overpriced, and most of the benefits are reaped by intermediaries. In this paper we build on prior research that proposes the use of blockchain as an enabler for trusted, decentralized asset documentation. Applying a socio-technical lens, we describe how blockchain-enabled multi-party certification affords dealers the action potential to send signals that are more closely correlated to the unobservable quality of the underlying good (i.e., signals with a higher fit) than the signals they send today. We then both theorize and experimentally explore the market effects of the two types of signals. Using data from a laboratory market experiment with 210 participants, we find empirical evidence that multi-party certification affords dealers the action potential to send signals of significantly higher fit than those sent by intermediaries alone, leading to a reduction in information asymmetries, a more efficient allocation of goods, and an increase in market fairness

Efeito da amputação unilateral do incisivo inferior sobre o metabolismo da glicose em glândulas submandibulares de ratos submetidas a desnervação simpática e parassimpática

O sistema nervoso autônomo é de grande importância na regulação da fisiologia das glândulas salivares, incluindo o processo sialadenotrófico. Já é bem conhecido o fato de que a função secretora, bem como, outras funções desempenhadas pelas glândulas salivares dependem de energia produzida nas glândulas. A histometria dos ácinos, algumas enzimas do metabolismo de carboidratos como, hexoquinase, fosfofrutoquinase-1, piruvato quinase, glicose-6-fosfato desidrogenase e lactato desidrogenase foram avaliados na glândula submandibular de ratos com desnervação simpática e parassimpática, submetidos a amputação unilateral dos dentes incisivos, cinco dias após a desnervação. Nas glândulas simpatectomizadas submetidas a amputação dos incisivos observou-se uma redução nas atividades da hexoquinase (27,5 - 36,7 %) e da fosofofrutoquinase-1 (22,8 - 38,4 %). Embora, nehuma variação foi observado nas atividades enzimáticas, houve uma redução significante do volume acinar.The autonomic nervous system is of major importance in the regulation of physiological functions of the salivary glands, including the sialadenotrophic process. It is well known that the secretory function as well as other functions in the salivary glands depend upon the energy produced in the gland. The acini volume density, some enzymes of the glucose metabolism, such as hexokinase, phosphofructokinase, pyruvate kinase, glucose-6-phosphate dehydrogenase and lactate dehydrogenase were evaluated following sympathetic and parasympathetic denervation of submandibular glands of rats, submitted to unilateral incisor amputation, five days after denervation. Sympathectomized glands submitted to amputation showed a reduction in the activity of hexokinase and phosphofructokinase-1, varying from 27.5 to 36.7 % for hexokinase and from 22.8 to 38.4 % for phosphofructokinase-1. Although no variation was observed in the enzymatic activity of parasympathectomized animals, the acini volume density showed a significant decrease

A Geometrically Supported z∼10z\sim10 Candidate Multiply-Imaged by the Hubble Frontier Fields Cluster Abell 2744

The deflection angles of lensed sources increase with their distance behind a given lens. We utilize this geometric effect to corroborate the $z_{phot}\simeq9.8$ photometric redshift estimate of a faint near-IR dropout, triply-imaged by the massive galaxy cluster Abell 2744 in deep Hubble Frontier Fields images. The multiple images of this source follow the same symmetry as other nearby sets of multiple images which bracket the critical curves and have well defined redshifts (up to $z_{spec}\simeq3.6$), but with larger deflection angles, indicating that this source must lie at a higher redshift. Similarly, our different parametric and non-parametric lens models all require this object be at $z\gtrsim4$, with at least 95\% confidence, thoroughly excluding the possibility of lower-redshift interlopers. To study the properties of this source we correct the two brighter images for their magnifications, leading to a SFR of $\sim0.3 M_{\odot}$/yr, a stellar mass of $\sim4\times10^{7} M_{\odot}$, and an age of $\lesssim220$ Myr (95\% confidence). The intrinsic apparent magnitude is 29.9 AB (F160W), and the rest-frame UV ($\sim1500 \AA$) absolute magnitude is $M_{UV,AB}=-17.6$. This corresponds to $\sim0.1 L^{*}_{z=8}$ ($\sim0.2 L^{*}_{z=10}$, adopting $dM^{*}/dz\sim0.45$), making this candidate one of the least luminous galaxies discovered at $z\sim10$.Comment: 7 pages, 4 figures, 1 table; V2: very minor changes, ApJ Letters Accepte

Photophysics and photochemistry of the beta-lapachone derived diphenyldihydrodioxin: generation and characterization of its cation radical

[EN] The photophysics and photochemistry of the beta-lapachone derived diphenyldihydrodioxin 3 were investigated using steady-state and time resolved techniques. Laser excitation of 3 leads to the formation of its cation radical 4 (absorption maxima at 410 and 450 nm and a lifetime of 10 mu s), which was confirmed by its thermal generation employing tris(2,4-dibromophenyl)-aminium hexachloroantimonate (BAHA) as the electron acceptor. The cation radical 4 was also formed via the triplet excited state of 3 through a triplet sensitized process using benzophenone (E-T = 69 kcal mol(-1)) as the sensitizer.Financial support by the Spanish Government (grant CTQ2012-32621) is gratefully acknowledged. We thank Prof. Julia Pérez-Prieto for making available the laser flash photolysis facilities at the University of Valencia. BB thanks Coordena- ção de Aperfeiçoamento do Pessoal do Ensino Superior (CAPES-Brazil) for a graduate fellowship. JCN-F thanks Generalitàt Valenciana for a Visiting Professor fellowship.Netto Ferreira, JC.; Lhiaubet ., VL.; Bernades, B.; Ferreira, ABB.; Miranda Alonso, MÁ. (2014). Photophysics and photochemistry of the beta-lapachone derived diphenyldihydrodioxin: generation and characterization of its cation radical. Photochemical & Photobiological Sciences. 13(12):1655-1660. https://doi.org/10.1039/C4PP00231HS16551660131

Microscopic resolution of the interplay of Kondo screening and superconducting pairing: Mn-phthalocyanine molecules adsorbed on superconducting Pb(111)

Magnetic molecules adsorbed on a superconductor give rise to a local competition of Cooper pair and Kondo singlet formation inducing subgap bound states. For Manganese-phthalocyanine molecules on a Pb(111) substrate, scanning tunneling spectroscopy resolves pairs of subgap bound states and two Kondo screening channels. We show in a combined approach of scaling and numerical renormalization group calculations that the intriguing relation between Kondo screening and superconducting pairing is solely determined by the hybridization strength with the substrate. We demonstrate that an effective one-channel Anderson impurity model with a sizable particle-hole asymmetry captures universal and non-universal observations in the system quantitatively. The model parameters and disentanglement of the two screening channels are elucidated by scaling arguments.Comment: 8 pages, 4 figure

Effect of Root Repair Materials and Bioactive Glasses on Microhardness of Dentin

Introduction: The use of bioactive glasses to re-establish or increase mechanical properties of the root dentin may be an interesting alternative. The aim of this study was to evaluate the effect of root repair materials and bioactive glasses on the microhardness of human root dentin. Methods and Materials: Sixty-four sectioned palatal roots of human molars were prepared and two slices were obtained of the middle third of each root (one corresponding to the control group, without treatment, and the other to the experimental group). The pairs of slices were randomly divided into four groups (n=16). The root canal of experimental slices were filled with one of the following materials: mineral trioxide aggregate (Angelus MTA, Angelus, Londrina, Paraná, Brazil), EndoSequence Root Repair Material (ERRM, Brassler, Savannah, GA, USA), Bioglass (45S5) and an experimental niobophosphate glass (NbG). The specimens were stored in an oven at 37ºC, in an environment with 100% humidity for 60 days. The specimens were subjected to a microhardness test. Four indentations were made at a distance of 20 µm from the root canal lumen. For microhardness analysis, comparing the experimental groups and their respective controls, the Student’s-t test was applied. For comparison of the percentage increase in microhardness between the groups, the data were statistically analyzed by using One-way ANOVA and Tukey’s test. The level of significance was set at 0.05. Results: All the materials significantly increased the dentin microhardness values (P<0.05). MTA showed a higher increase in microhardness (94.8±42.7%), similar to that of EndoSequence (62.3±39.9%). The 45S5 (46.5±30.0%) and NbG (53.8±31.3%) showed the lowest percentages of increase in microhardness, but were statistically similar to those of EndoSequence. Conclusion: All the materials tested were capable of increasing root dentin microhardness.Keywords: Bioactive Glass 45S5; Dental Materials; Hardness Test; Microhardness Tests; Root Canal Filling Material

Micro Push-out Bond Strength and Bioactivity Analysis of a Bioceramic Root Canal Sealer

Introduction: Bioactive endodontic sealers have been developed to improve the quality of root canal obturation. EndoSequence Bioceramic (BC) Sealer is amongst calcium silicate-based materials recently developed for permanent root canal filling. The objective of this study was to evaluate the bioactivity of BC Sealer and its micro push-out bond strength to dentin compared to AH-Plus (AH) sealer. Methods and Materials: To perform the micro push-out test, 24 root canals of mandibular premolars were instrumented and divided into two groups (n=12). Each root was cut into 4 slices and lumens of the canals were filled with the sealers and submitted to micro push-out test. Failure mode was assessed using scanning electron microscopy (SEM). Bioactivity of BC sealer was investigated with scanning electron microscopy/energy-dispersive X-ray (SEM/EDS) and X-ray diffraction (XRD). Bioactivity assessments were reported descriptively. Bond strength data were analyzed by parametric t-test (α=5%). Results: In micro push-out test AH had higher bond strength mean values (16.29 MPa) than BC sealer (9.48 MPa) (P<0.05). Both groups had low amount of adhesive failure. SEM showed the presence of a mineral precipitate after 30 days and EDS analysis showed that those precipitates have high proportion of Ca. XRD showed peaks of crystalline phases of calcium carbonate compatible with the bioactivity. Conclusion: BC sealer showed indications of bioactivity and lower bond strength to dentine compared to AH.Keywords: Bioactivity; Bioceramic; Dentine; Micro Push-Out Bond Strength; Root Canal Seale