3,616 research outputs found
Fractal Subsystem Symmetries, 't Hooft Anomalies, and UV/IR Mixing
In this work, we study unconventional anisotropic topologically ordered
phases in 3d that manifest type-II fractonic physics along sub-manifolds. While
they behave as usual topological order along a preferred spatial direction,
their physics along perpendicular planes is dictated by the presence of fractal
subsystem symmetries, completely restricting the mobility of anyonic
excitations and their bound states. We consider an explicit lattice model
realization of such phases and proceed to study their properties under periodic
boundary conditions and, later, in the presence of boundaries. We find that for
specific lattice sizes, the system possesses line and fractal membrane
symmetries that are mutually anomalous, resulting in a non-trivially gapped
ground state space. This amounts to the spontaneous breaking of the fractal
symmetries, implying a sub-extensive ground state degeneracy. For the remaining
system sizes the fractal symmetries are explicitly broken by the periodic
boundary conditions, which is intrinsically related to the uniqueness of the
ground state. Despite of that, the system is still topologically ordered since
locally created quasi-particles have nontrivial mutual statistics and, in the
presence of boundaries, it still presents anomalous edge modes. The intricate
symmetry interplay dictated by the lattice size is a wild manifestation of
ultraviolet/infrared (UV/IR) mixing.Comment: 7+7 pages, 5+5 figure
Chloroquine Analogues as Leads against Pneumocystis Lung Pathogens
The impact of Pneumocystis pneumonia (PcP) on morbidity and mortality remains substantial for immunocompromised individuals, including those afflicted by HIV infection, organ transplantation, cancer, autoimmune diseases, or subject to chemotherapy or corticosteroid-based therapies. Previous work from our group has shown that repurposing antimalarial compounds for PcP holds promise for treatment of this opportunistic infection. Following our previous discovery of chloroquine analogues with dual-stage antimalarial action both in vitro and in vivo, we now report the potent action of these compounds on Pneumocystis carinii in vitro Identification of chloroquine analogues as anti-PcP leads is an unprecedented finding.info:eu-repo/semantics/publishedVersio
Opportunistic Maintenance Based on CUSUM Control Charts
The use of a Ship Maintenance Management System is fundamental for the good performance of equipments and the entire platform. Over the systematic maintenance, the opportunistic maintenance is a concept that aims to minimize outages and costs preventing undesirable failures. To implement this kind of
maintenance statistical methodologies must be used. The Cumulative Sum charts have a very good performance applied to processes control in quality control.
We proposed the use of Modified Cumulative Sum control charts to equipment maintenance.The data under study are observations of cooling water and oil temperatures from a diesel generator. In the first phase, we will apply traditional control charts, and, in the second phase, the Cumulative charts with a certain Average Run Length will be used. Then we will compare the results and extract conclusions,
presenting measures for improvement.info:eu-repo/semantics/publishedVersio
Prediction of adverse pregnancy outcomes by extreme values of first trimester screening markers
Background To determine the association between extreme values of first trimester markers and adverse pregnancy outcomes.
Methods A retrospective cohort study of 916 women who underwent first-trimester combined screening during 2015 was performed. Extreme values of NT, pregnancy-associated plasma protein-A (PAPP-A) and free -hCG, and their association with adverse pregnancy outcomes were analyzed.
Results Low PAPP-A (<10th percentile) was associated with an increased risk for preeclampsia (adjusted odds ratio (AOR) 4.13), fetal growth restriction (AOR 3.94) and abruptio placentae (AOR 52.63). Abnormally low or high free -hCG, high PAPP-A or increased NT was not associated with an increased risk for adverse outcomes.
Discussion PAPP-A <10th percentile could be associated with an increased risk for adverse outcomes. However, the majority of patients with these events do not have abnormal PAPP-A and few patients with PAPP-A <10th percentile will have an adverse outcome.info:eu-repo/semantics/publishedVersio
Control Charts Limits Flexibility Based on the Equipment Conditions
Condition Based Maintenance became an important development in industrial and transport equipment maintenance efforts. Many statistical methodologies have been applied in this area. These methodologies are usually applied off-line: after the data is collected. We propose an online, real-time condition monitoring system based on a modified control chart, applied to engine parameters. These charts should be
flexible enough and its control limits should reflect the equipment state, the manufacturer specifications and onboard meteorological conditions. In this study we will develop a methodology to specify flexible chart control limits. The experimental equipment is a combined diesel or gas propulsion system. Two phases will be
assumed. In phase 1 the equipment and historical data are analyzed, studying historical data, which leads to the definition of equipment parameters. In phase 2, new data is obtained by simulation, and the Exponentially Weighted Moving Average charts are applied considering flexible limits.info:eu-repo/semantics/publishedVersio
Composição química de composto orgânico preparado com esterco de eqüino e leucena. (Leucaena lleucocephalla Lam de Wit).
A compostagem é um dos meios mais eficientes para a transformação dos resíduos vegetais e animais em produtos orgânicos utilizáveis na agricultura, constituindo alternativa para obtenção de insumos, reduzindo a utilização de fertilizantes químicos. Este trabalho foi conduzido na Fazenda Escola da Universidade Estadual do Maranhão – UEMA, com o objetivo de avaliar a composição química do composto de esterco eqüino e leucena, em diferentes proporções. Os tratamentos foram as diferentes pilhas: T1, Testemunha (100kg de esterco de eqüino), T2, 75kg de esterco de eqüino + 25kg de leucena; T3, 50kg de esterco de eqüino +50kg de leucena; T4, 25kg de esterco de eqüino + 75kg de leucena. Aos 67 dias após a montagem das pilhas de compostagem foram coletadas amostras dos compostos resultantes de cada tratamento, para análise da composição química; teores de Matéria Orgânica (M.O), pH, Fósforo (P), Potássio (K), Cálcio (Ca), Magnésio (Mg), Hidrogênio e Alumínio (H+Al), Carbono e Nitrogênio. De acordo com resultados obtidos, os tratamentos diferiram estatisticamente entre si, em relação as características avaliadas. Os resultados das análises demonstraram que o T4 (75kg de esterco de eqüino + 25kg de leucena) apresentou valores elevados em relação à testemunha, T1 nos teores de M.O (14,9%); P (857mg/dm3); e Mg (77,5mmol/dm3), associado a um pH de acidez baixa (6,5), resultando um composto de excelente qualidade. Todos os tratamentos apresentaram características químicas em níveis satisfatórios, em relação à fertilidade do solo, exigidos pela maioria das espécies cultivadas no Brasil
Building on surface-active ionic liquids for the rescuing of the antimalarial drug chloroquine
Ionic liquids derived from classical antimalarials are emerging as a new approach towards the cost-effective rescuing of those drugs. Herein, we disclose novel surface-active ionic liquids derived from chloroquine and natural fatty acids whose antimalarial activity in vitro was found to be superior to that of the parent drug. The most potent ionic liquid was the laurate salt of chloroquine, which presented IC50 values of 4 and 110 nM against a chloroquine-sensitive and a chloroquine-resistant strain of Plasmodium falciparum, respectively, corresponding to an 11-and 6-fold increase in potency as compared to the reference chloroquine bisphosphate salt against the same strains. This unprecedented report opens new perspectives in both the fields of malaria chemotherapy and of surface-active ionic liquids derived from active pharmaceutical ingredients.publishersversionpublishe
MCHO – A new indicator for insulation conditions in transmission lines
AbstractConventionally monitoring operating conditions of a power transmission line is accomplished by periodic inspections along this line. This monitoring allows corrective maintenance by finding faults during the inspection. But in more efficient maintenance, predictive techniques that are characterized by real-time monitoring should be employed. Such predictive techniques allow for verifying the working status of the line by using normal working models to detect faults and fault models for diagnosis. This paper presents a study that used a mathematical model appropriate for application to predictive maintenance of transmission line segments at low cost, without the need for sensors distributed along the line, and presenting a new indicator of transmission line operation conditions. By tracking the leakage current of transmission lines, this model allows for estimating the current line insulation status. Once the current line insulation status is known, it is possible to compare it against other future status and verify the progress of the insulation conditions of that line. The model uses a new indicator, called MCHO, which can detect and diagnose both normal and abnormal operating conditions of a power transmission line. This new indicator is the capacitance of the harmonic frequencies of the transmission line leakage current. The model was validated through measurements obtained on a stretch of transmission line
Electrical and microstructural changes of β-PVDF under uniaxial stress studied by scanning force microscopy
Chain reorientation may be induced in polyvinylidene fluoride (PVDF) in its β-phase by
applying a deformation perpendicular to the pre-oriented polymeric chains. This reorientation
begins right after the yielding point and seems to be completed when the stress-strain curve
stabilizes. As the deformation process plays an important role in the processing and optimisation
properties of the material for practical applications, different deformation stress was applied to the
PVDF lamellas and their topographic change and piezoelectric response were studied by means of
scanning force microscopy in a piezo-response mode.
The experimental results confirm the previously observed chain reorientation that occurs right after
the yielding point and that is completed when the yielding region is passed. This reorientation is
accompanied by a stretching of the granular structures observed in the topographical images and
variations in the domain response. The observed results help to explain the variations in the
macroscopic response of the material.Fundação para a Ciência e a Tecnologia (FCT) - Grant POCTI/CTM/33501/99, POCI/CTM/59425/2004.Measurement Specialties Inc
Tuning peptide-based hydrogels: co-assembly with composites driving the highway to technological applications
Self-assembled peptide-based gels provide several advantages for technological applications. Recently, the co-assembly of gelators has been a strategy to modulate and tune gel properties and even implement stimuli-responsiveness. However, it still comprises limitations regarding the required library of compounds and outcoming properties. Hence, efforts have been made to combine peptide-based gels and (in)organic composites (e.g., magnetic nanoparticles, metal nanoparticles, liposomes, graphene, silica, clay, titanium dioxide, cadmium sulfide) to endow stimuli-responsive materials and achieve suitable properties in several fields ranging from optoelectronics to biomedical. Herein, we discuss the recent developments with composite peptide-based gels including the fabrication, tunability of gels' properties, and challenges on (bio)technological applications.This work was funded by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding of CF-UM-UP (UIDB/04650/2020) and CQUM (UIDB/00686/2020), and by Ministerio de Economía y Competitividad de España (PID2020-113704RB-I00 and PID2020-119242RB-I00), Xunta de Galicia (Centro Singular de Investigación de Galicia—Accreditation 2019-2022 ED431G 2019/06 and IN607A 2018/5 and project ED431C 2020-06), and European Union (EU-ERDF Interreg V-A—Spain-Portugal 0245_IBEROS_1_E, 0712_ACUINANO_1_E, and 0624_2IQBIONEURO_6_E, and Interreg Atlantic Area NANOCULTURE 1.102.531), and the European Union H2020-MSCA-RISE-2019 PEPSA-MATE 872233 project. S.R.S. Veloso acknowledges FCT for a PhD grant (SFRH/BD/144017/2019). Support from MAP-Fis Doctoral Programme is also acknowledged
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