Isotropic A-branes and the stability condition

The existence of a new kind of branes for the open topological A-model is argued by using the generalized complex geometry of Hitchin and the SYZ picture of mirror symmetry. Mirror symmetry suggests to consider a bi-vector in the normal direction of the brane and a new definition of generalized complex submanifold. Using this definition, it is shown that there exists generalized complex submanifolds which are isotropic in a symplectic manifold. For certain target space manifolds this leads to isotropic A-branes, which should be considered in addition to Lagrangian and coisotropic A-branes. The Fukaya category should be enlarged with such branes, which might have interesting consequences for the homological mirror symmetry of Kontsevich. The stability condition for isotropic A-branes is studied using the worldsheet approach.Comment: 19 page

Yield and morphology of Nopalea cochenillifera under N fertilization and biological inoculation

Received: August 15th, 2023 ; Accepted: October 30th, 2023 ; Published: November 9th, 2023 ; Correspondence: [email protected]; [email protected] objective was to evaluate the effect of inoculation with Azospirillum brasilense and levels of nitrogen fertilization on the productive aspects of the spineless cactus (Nopalea cochenillifera). The experiment was carried in Ribeirão do Largo, Southwest region of the state of Bahia, from April 2019 to April 2020. The experiment was carried out in a 2×4 factorial, in a randomized block design with eight treatments and four replications. The treatments consisted of the absence or inoculation with Azospirillum brasilense and nitrogen fertilization levels 0, 50, 100 and 150 kg– ¹ of N ha–¹ . There was a positive effect for the use of the bacteria on cladode area index, height, number of secondary, tertiary and total cladodes, total weight for cladodes of all orders and also for final weight per ha–¹ . There was a significant effect of the use of the inoculant for the levels of total soluble sugars and starch, where there was a decrease in the values for the treatments submitted to the use of the bacteria. There was a quadratic effect for the weight of the tertiary cladodes, number of tertiary cladodes and total of spineless cactus when submitted to nitrogen fertilization levels. There was a linear test for cladodes area index when nitrogen fertilization was used. The use of Azospirillum brasilense is positive for the cultivation of spineless cactus, improving development and increasing crop productivity

Emergence and fate of stem cell-like Tcf7⁺ CD8⁺ T cells during a primary immune response to viral infection.

In response to infection, naïve CD8 <sup>+</sup> T (T <sub>N</sub> ) cells yield a large pool of short-lived terminal effector (T <sub>TE</sub> ) cells that eliminate infected host cells. In parallel, a minor population of stem cell-like central memory (T <sub>CM</sub> ) cells forms, which has the capacity to maintain immunity after pathogen clearance. It has remained uncertain whether stem-like T <sub>CM</sub> cells arise by dedifferentiation from a subset of cytolytic T <sub>TE</sub> cells or whether priming generates stem-like cells capable of seeding the T <sub>CM</sub> compartment and, if so, when cytolytic T <sub>TE</sub> cells branch off. Here, we show that CD8 <sup>+</sup> T cells with stem-like properties, which are identified by the expression of TCF1 (encoded by Tcf7), are present across the primary response to infection. Priming programs T <sub>N</sub> cells to undergo multiple cell divisions, over the course of which TCF1 expression is maintained. These TCF1 <sup>+</sup> cells further expand relatively independently of systemic inflammation, antigen dose, or affinity, and they quantitatively yield TCF1 <sup>+</sup> T <sub>CM</sub> cells after pathogen clearance. Inflammatory signals suppress TCF1 expression in early divided TCF1 <sup>+</sup> cells. TCF1 down-regulation is associated with the irreversible loss of self-renewal capacity and the silencing of stem/memory genes, which precedes the stable acquisition of a T <sub>TE</sub> state. TCF1 expression restrains cell cycling, explaining in part the limited expansion of TCF1 <sup>+</sup> relative to TCF1 <sup>-</sup> cells during the primary response. Thus, our data are consistent with terminal differentiation of effector cells being a step-wise process that is initiated by inflammation in primed stem-like cells, which would otherwise become central memory cells by default

Development of poly(l-Lactic Acid)-based bending actuators

This work reports on the development of bending actuators based on poly(l-lactic acid) (PLLA)/ionic liquid (IL) blends, through the incorporation of 40% wt. of the 1-ethyl-methylimidazolium bis(trifluoromethylsulfonyl)imide ([Emim][TFSI]) IL. The films, obtained by solvent casting at room temperature and 50 °C, were subjected to several post-thermal treatments at 70, 90, 120 and 140 °C, in order to modify the crystallinity of the films. The influence of the drying temperature and of [Emim][TFSI] blending on the morphological, structural, mechanical and electrical properties of the composite materials were studied. The IL induced the formation of a porous surface independently of the processing conditions. Moreover, the [Emim][TFSI] dopant and the post-thermal treatments at 70 °C promoted an increase of the degree of crystallinity of the samples. No significant changes were observed in the degree of crystallinity and Young Modulus for samples with thermal treatment between 70 and 140 °C. The viability of the developed high ionic conductive blends for applications as soft actuators was evaluated. A maximum displacement of 1.7 mm was achieved with the PLLA/[Emim][TFSI] composite prepared at 50 °C and thermally treated at 140 °C, for an applied voltage of 10 Vpp, at a frequency of 100 mHz. This work highlights interesting avenues for the use of PLLA in the field of actuators.The authors thank the FCT—Fundação para a Ciência e Tecnologia—for financial support under the Strategic Funding UID/FIS/04650/2020, and PEST-C/QUI/UIO686/2019, the Associated Laboratory Research Unit for Green Chemistry, Technologies and Clean Processes, LAQV (financed by national funds from FCT/MEC, UID/QUI/50006/2020 and ERDF under the PT2020, POCI-01-0145-FEDER-007265) and projects PTDC/BTM-MAT/28237/2017 and PTDC/EMD-EMD/28159/2017. DMC and LCF also thank the grants SFRH/BPD/121526/2016 and SFRH/BD/145345/2019, respectively

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Classification of protein interaction sentences via gaussian processes

The increase in the availability of protein interaction studies in textual format coupled with the demand for easier access to the key results has lead to a need for text mining solutions. In the text processing pipeline, classification is a key step for extraction of small sections of relevant text. Consequently, for the task of locating protein-protein interaction sentences, we examine the use of a classifier which has rarely been applied to text, the Gaussian processes (GPs). GPs are a non-parametric probabilistic analogue to the more popular support vector machines (SVMs). We find that GPs outperform the SVM and na\"ive Bayes classifiers on binary sentence data, whilst showing equivalent performance on abstract and multiclass sentence corpora. In addition, the lack of the margin parameter, which requires costly tuning, along with the principled multiclass extensions enabled by the probabilistic framework make GPs an appealing alternative worth of further adoption

Waist circumference as a mediator of biological maturation effect on the motor coordination in children

AbstractObjectiveThe present study aimed to: 1) examine the association of biological maturation effect on performance at a motor coordination battery and 2) to assess whether the association between biological maturation and scores obtained in motor coordination tests is mediated by some anthropometric measurement.MethodsThe convenience sample consisted of 73 male children aged 8 years old. Anthropometric data considered the height, body mass, sitting height, waist circumference, body mass index, fat mass and fat-free mass estimates. Biological maturation was assessed by the percentage of the predicted mature stature. Motor coordination was tested by the Körperkoordinationstest für Kinder. A partial correlation between anthropometric measurements, z-score of maturation and the motor coordination tests were performed, controlling for chronological age. Finally, causal mediation analysis was performed.ResultsHeight, body mass, waist circumference and fat mass showed a slight to moderate inverse correlation with motor coordination. Biological maturation was significantly associated with the balance test with backward walking (r=−0.34). Total mediation of the waist circumference was identified in the association between biological maturation and balance test with backward walking (77%).ConclusionsWe identified an association between biological maturation and KTK test performance in male children and also verified that there is mediation of waist circumference. It is recommended that studies be carried out with female individuals and at other age ranges

Bubbling AdS and Vacuum String Field Theory

We show that a family of 1/2--BPS states of $\N=4$ SYM is in correspondence with a family of classical solutions of VSFT with a $B$--field playing the role of the inverse Planck constant. We show this correspondence by relating the Wigner distributions of the $N$ fermion systems representing such states, to low energy space profiles of systems of VSFT D-branes. In this context the Pauli exclusion principle appears as a consequence of the VSFT projector equation. The family of 1/2--BPS states maps through coarse--graining to droplet LLM supergravity solutions. We discuss the possible meaning of the corresponding coarse graining in the VSFT side.Comment: 23 pages, subsection 4.1 added, Appendix suppressed. to be published in NP

Soil biochemistry and microbial activity in vineyards under conventional and organic management at Northeast Brazil.

The São Francisco Submedium Valley is located at the Brazilian semiarid region and is an important center for irrigated fruit growing. This region is responsible for 97% of the national exportation of table grapes, including seedless grapes. Based on the fact that orgThe São Francisco Submedium Valley is located at the Brazilian semiarid region and is an important center for irrigated fruit growing. This region is responsible for 97% of the national exportation of table grapes, including seedless grapes. Based on the fact that organic fertilization can improve soil quality, we compared the effects of conventional and organic soil management on microbial activity and mycorrhization of seedless grape crops. We measured glomerospores number, most probable number (MPN) of propagules, richness of arbuscular mycorrhizal fungi (AMF) species, AMF root colonization, EE-BRSP production, carbon microbial biomass (C-MB), microbial respiration, fluorescein diacetate hydrolytic activity (FDA) and metabolic coefficient (qCO2). The organic management led to an increase in all variables with the exception of EE-BRSP and qCO2. Mycorrhizal colonization increased from 4.7% in conventional crops to 15.9% in organic crops. Spore number ranged from 4.1 to 12.4 per 50 g-1 soil in both management systems. The most probable number of AMF propagules increased from 79 cm-3 soil in the conventional system to 110 cm-3 soil in the organic system. Microbial carbon, CO2 emission, and FDA activity were increased by 100 to 200% in the organic crop. Thirteen species of AMF were identified, the majority in the organic cultivation system. Acaulospora excavata, Entrophospora infrequens, Glomus sp.3 and Scutellospora sp. were found only in the organically managed crop. S. gregaria was found only in the conventional crop. Organically managed vineyards increased mycorrhization and general soil microbial activity

Exciton Spin Dynamics in Semiconductor Quantum Wells

In this paper we will review Exciton Spin Dynamics in Semiconductor Quantum Wells. The spin properties of excitons in nanostructures are determined by their fine structure. We will mainly focus in this review on GaAs and InGaAs quantum wells which are model systems.Comment: 55 pages, 27 figure