Scale-Invariant Transition Probabilities in Free Word Association Trajectories

Free-word association has been used as a vehicle to understand the organization of human thoughts. The original studies relied mainly on qualitative assertions, yielding the widely intuitive notion that trajectories of word associations are structured, yet considerably more random than organized linguistic text. Here we set to determine a precise characterization of this space, generating a large number of word association trajectories in a web implemented game. We embedded the trajectories in the graph of word co-occurrences from a linguistic corpus. To constrain possible transport models we measured the memory loss and the cycling probability. These two measures could not be reconciled by a bounded diffusive model since the cycling probability was very high (16% of order-2 cycles) implying a majority of short-range associations whereas the memory loss was very rapid (converging to the asymptotic value in ∼7 steps) which, in turn, forced a high fraction of long-range associations. We show that memory loss and cycling probabilities of free word association trajectories can be simultaneously accounted by a model in which transitions are determined by a scale invariant probability distribution

Automatic and unbiased segmentation and quantification of myofibers in skeletal muscle

Skeletal muscle has the remarkable ability to regenerate. However, with age and disease muscle strength and function decline. Myofiber size, which is affected by injury and disease, is a critical measurement to assess muscle health. Here, we test and apply Cellpose, a recently developed deep learning algorithm, to automatically segment myofibers within murine skeletal muscle. We first show that tissue fixation is necessary to preserve cellular structures such as primary cilia, small cellular antennae, and adipocyte lipid droplets. However, fixation generates heterogeneous myofiber labeling, which impedes intensity-based segmentation. We demonstrate that Cellpose efficiently delineates thousands of individual myofibers outlined by a variety of markers, even within fixed tissue with highly uneven myofiber staining. We created a novel ImageJ plugin (LabelsToRois) that allows processing of multiple Cellpose segmentation images in batch. The plugin also contains a semi-automatic erosion function to correct for the area bias introduced by the different stainings, thereby identifying myofibers as accurately as human experts. We successfully applied our segmentation pipeline to uncover myofiber regeneration differences between two different muscle injury models, cardiotoxin and glycerol. Thus, Cellpose combined with LabelsToRois allows for fast, unbiased, and reproducible myofiber quantification for a variety of staining and fixation conditions.Fil: Waisman, Ariel. Fundacion P/la Lucha C/enferm.neurologicas Infancia. Instituto de Neurociencias. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Ciudad Universitaria. Instituto de Neurociencias.; ArgentinaFil: Norris, Alessandra. University of Florida; Estados UnidosFil: Elias Costa, Martin. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Kopinke, Daniel. University of Florida; Estados Unido

Extraction of corn colorants (Zea mays L.)

Natural colorants were craftly made and widely used before the discovery of the synthetic colorants. The study and the use of natural colorants have become important again in the last few years due to questions raised by the international health organizations and consumers related to the indiscriminate use of synthetic colorants which were linked to the development of degenerative illnesses and environmental impact. The colorant extracted from purple corn (Zea Mays L.) was used by the Inca civilization to prepare food and to dye textile fibers. In this work, pigments from the anthocyanin group were extracted from purple corn and red corn (Zea Mays L.) varieties and were later characterized. Three extraction methods were used: immersion, lixiviation with some changes, and supercritical extraction (ESC). The best method of extraction was lixiviation, which reached 88% (m/m) of performance as a function of the mass of colorant extracted and of the raw materials. Also using the modified lixiviation it was possible to concentrate the acylate compounds in 3% as well as to recover 85% of solvent used. A pH indicator was obtained by fixing the anthocyanins on a filter paper based on anthocyanins stabilization. This technique can be utilized in laboratory chemistry lessons.Os corantes naturais foram amplamente utilizados de forma artesanal até antes do surgimento dos corantes sintéticos. O estudo e uso dos corantes naturais voltaram a ter importância nestes últimos anos devido aos questionamentos dos organismos internacionais da saúde e dos consumidores pelo uso indiscriminado dos corantes sintéticos, ligados ao desenvolvimento de doenças degenerativas e ao impacto ambiental. O corante extraído do milho roxo (Zea mays L.) tem sido utilizado ao longo da história pela civilização Inca na preparação de alimentos e no tingimento de fibras têxteis. Neste trabalho, os pigmentos do grupo das antocianinas foram extraídos das variedades de milho roxo e do milho vermelho (Z. mays L.) e depois foram caracterizados. Três métodos de extração foram utilizados: imersão, lixiviação com algumas modificações e extração supercrítica (ESC). O melhor método para extração foi o da lixiviação que alcançou 88% (m/m) de rendimento, em função da massa do corante extraído e da matéria-prima. Também utilizando a lixiviação modificada, foi possível concentrar em 3% os compostos acilados, assim como recuperar 85% dos solventes utilizados. Um indicador de pH foi obtido pela fixação das antocianinas num papel de filtro, com base na estabilidade das antocianinas, ferramenta que pode ser utilizada em laboratórios de ensino de química.6269Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

PLANTAS NATIVAS E NATURALIZADAS COM POTENCIAL ORNAMENTAL DO CAMPUS DOM DELGADO, UNIVERSIDADE FEDERAL DO MARANHÃO, SÃO LUÍS, MARANHÃO

Apesar do potencial ornamental, as plantas nativas do Brasil não são devidamente aproveitadas quanto às suas possibilidades de uso e esse aspecto fica evidente no paisagismo das cidades brasileiras, onde mais de 50% das espécies utilizadas são exóticas. Visando ampliar o uso de plantas nativas e naturalizadas no Brasil e valorizar a diversidade da flora do Maranhão, o presente estudo identificou plantas nativas com potencial ornamental do campus Dom Delgado, Universidade Federal do Maranhão (UFMA). As espécies com potencial ornamental foram estudadas com base em coletas realizadas durante outubro e novembro de 2022 em fragmentos florestais urbanos e áreas adjacentes do campus Dom Delgado, São Luís (MA) e em um levantamento da flora nativa desses mesmos fragmentos florestais urbanos da UFMA. Trinta e duas espécies (três naturalizadas e 29 nativas) tiveram uso ornamental sugerido. As famílias com mais espécies com esse potencial foram Fabaceae (cinco espécies, Acanthaceae (três espécies) e Asteraceae (três espécies). Os hábitos herbáceo (43,75%), trepador (31,25%) e arbustivo (18,75%) foram os mais representativos. O campus Dom Delgado (UFMA) apresenta considerável variedade de espécies nativas com potencial ornamental, evidenciando a necessidade de valorizá-las na jardinagem e no paisagismo do Maranhão e do Brasil

Using modeling tools for implementing feasible land use and nature conservation governance systems in small islands e The Pico Island (Azores) case-study

The present study deals with the development of systematic conservation planning as management instrument in small oceanic islands, ensuring open systems of governance, and able to integrate an informed and involved participation of the stakeholders. Marxan software was used to define management areas according a set of alternative land use scenarios considering different conservation and management paradigms. Modeled conservation zones were interpreted and compared with the existing protected areas allowing more fused information for future trade-outs and stakeholder's involvement. The results, allowing the identification of Target Management Units (TMU) based on the consideration of different development scenarios proved to be consistent with a feasible development of evaluation approaches able to support sound governance systems. Moreover, the detailed geographic identification of TMU seems to be able to support participated policies towards a more sustainable management of the entire islan

Measurement of the lepton charge asymmetry in W-boson decays produced in p-pbar collisions

We describe a measurement of the charge asymmetry of leptons from W boson decays in the rapidity range 0 enu, munu events from 110+/-7 pb^{-1}of data collected by the CDF detector during 1992-95. The asymmetry data constrain the ratio of d and u quark momentum distributions in the proton over the x range of 0.006 to 0.34 at Q2 \approx M_W^2. The asymmetry predictions that use parton distribution functions obtained from previously published CDF data in the central rapidity region (0.0<|y_l|<1.1) do not agree with the new data in the large rapidity region (|y_l|>1.1).Comment: 13 pages, 3 tables, 1 figur

Effects of Spider Venom Toxin PWTX-I (6-Hydroxytrypargine) on the Central Nervous System of Rats

The 6-hydroxytrypargine (6-HT) is an alkaloidal toxin of the group of tetrahydro-β-carbolines (THβC) isolated from the venom of the colonial spider Parawixia bistriata. These alkaloids are reversible inhibitors of the monoamine-oxidase enzyme (MAO), with hallucinogenic, tremorigenic and anxiolytic properties. The toxin 6-HT was the first THβC chemically reported in the venom of spiders; however, it was not functionally well characterized up to now. The action of 6-HT was investigated by intracerebroventricular (i.c.v.) and intravenous (i.v.) applications of the toxin in adult male Wistar rats, followed by the monitoring of the expression of fos-protein, combined with the use of double labeling immunehistochemistry protocols for the detection of some nervous receptors and enzymes related to the metabolism of neurotransmitters in the central nervous system (CNS). We also investigated the epileptiform activity in presence of this toxin. The assays were carried out in normal hippocampal neurons and also in a model of chronic epilepsy obtained by the use of neurons incubated in free-magnesium artificial cerebro-spinal fluid (ACSF). Trypargine, a well known THβC toxin, was used as standard compound for comparative purposes. Fos-immunoreactive cells (fos-ir) were observed in hypothalamic and thalamic areas, while the double-labeling identified nervous receptors of the sub-types rGlu2/3 and NMR1, and orexinergic neurons. The 6-HT was administrated by perfusion and ejection in “brain slices” of hippocampus, inducing epileptic activity after its administration; the toxin was not able to block the epileptogenic crisis observed in the chronic model of the epilepsy, suggesting that 6-HT did not block the overactive GluRs responsible for this epileptic activity

Measurement of the Strong Coupling Constant from Inclusive Jet Production at the Tevatron pˉp\bar pp Collider

We report a measurement of the strong coupling constant, $\alpha_s(M_Z)$, extracted from inclusive jet production in $p\bar{p}$ collisions at $\sqrt{s}=$1800 GeV. The QCD prediction for the evolution of $\alpha_s$ with jet transverse energy $E_T$ is tested over the range 40<$E_T$<450 GeV using $E_T$ for the renormalization scale. The data show good agreement with QCD in the region below 250 GeV. In the text we discuss the data-theory comparison in the region from 250 to 450 GeV. The value of $\alpha_s$ at the mass of the $Z^0$ boson averaged over the range 40<$E_T$<250 GeV is found to be $\alpha_s(M_{Z})= 0.1178 \pm 0.0001{(\rm stat)}^{+0.0081}_{-0.0095}{\rm (exp. syst)}$. The associated theoretical uncertainties are mainly due to the choice of renormalization scale (^{+6%}_{-4%}) and input parton distribution functions (5%).Comment: 7 pages, 3 figures, using RevTeX. Submitted to Physical Review Letter

Measurement of the ttˉproductioncrosssectionint\bar{t} production cross section in p\bar{p}collisionsat collisions at \sqrt{s}$ = 1.8 TeV

We update the measurement of the top production cross section using the CDF detector at the Fermilab Tevatron. This measurement uses $t\bar{t}$ decays to the final states $e+\nu$+jets and $\mu+\nu$+jets. We search for $b$ quarks from $t$ decays via secondary-vertex identification or the identification of semileptonic decays of the $b$ and cascade $c$ quarks. The background to the $t\bar{t}$ production is determined primarily through a Monte Carlo simulation. However, we calibrate the simulation and evaluate its uncertainty using several independent data samples. For a top mass of 175 $GeV/c^2$, we measure $\sigma_{t\bar{t}}=5.1 \pm 1.5$ pb and $\sigma_{t\bar{t}}=9.2 \pm 4.3$ pb using the secondary vertex and the lepton tagging algorithms, respectively. Finally, we combine these results with those from other $t\bar{t}$ decay channels and obtain $\sigma_{t\bar{t}} = 6.5^{+1.7}_{-1.4}$ pb.Comment: The manuscript consists of 130 pages, 35 figures and 42 tables in RevTex. The manuscript is submitted to Physical Review D. Fixed typo in author lis

Search for a Fourth-Generation Quark More Massive than the Z0 Boson in ppbar Collisions at sqrt(s) = 1.8 TeV

We present the results of a search for pair production of a fourth-generation charge -1/3 quark (b') in sqrt(s)=1.8 TeV ppbar collisions using 88 pb^(-1) of data obtained with the Collider Detector at Fermilab. We assume that both quarks decay via the flavor-changing neutral current process b' -> bZ and that the b' mass is greater than m_Z + m_b. We studied the decay mode b'b'bar -> ZZ b bbar where one Z0 decays into e^+e^- or mu^+ mu^- and the other decays hadronically, giving a signature of two leptons plus jets. An upper limit on the cross section of ppbar -> b'b'bar times [BR (b' -> bZ)]^2 is established as a function of the b' mass. We exclude at 95% confidence level a b' quark with mass between 100 and 199 GeV/c^2 for BR(b' -> bZ) = 100%.Comment: 12 pages, 2 figures, submitted to Phys. Rev. Letters on 9/12/9