Nucleon Sigma Term and In-medium Quark Condensate in the Modified Quark-Meson Coupling Model

We evaluate the nucleon sigma term and in-medium quark condensate in the modified quark-meson coupling model which features a density-dependent bag constant. We obtain a nucleon sigma term consistent with its empirical value, which requires a significant reduction of the bag constant in the nuclear medium similar to those found in the previous works. The resulting in-medium quark condensate at low densities agrees well with the model independent linear order result. At higher densities, the magnitude of the in-medium quark condensate tends to increase, indicating no tendency toward chiral symmetry restoration.Comment: 9 pages, modified version to be publishe

Beyond the operating room: do hospital characteristics have an impact on surgical site infections after colorectal surgery? A systematic review

Background: Hospital characteristics have been recognized as potential risk factors for surgical site infection for over 20 years. However, most research has focused on patient and procedural risk factors. Understanding how structural and process variables influence infection is vital to identify targets for effective interventions and to optimize healthcare services. The aim of this study was to systematically review the association between hospital characteristics and surgical site infection in colorectal surgery. Main body: A systematic literature search was conducted using PubMed, Scopus and Web of Science databases until the 31st of May, 2021. The search strategy followed the Participants, Exposure/Intervention, Comparison, Outcomes and Study design. The primary outcome of interest was surgical site infection rate after colorectal surgery. Studies were grouped into nine risk factor typologies: hospital size, ownership affiliation, being an oncological hospital, safety-net burden, hospital volume, surgeon caseload, discharge destination and time since implementation of surveillance. The STROBE statement was used for evaluating the methodological quality. A total of 4703 records were identified, of which 172 were reviewed and 16 were included. Studies were published between 2008 and 2021, and referred to data collected between 1996 and 2016. Surgical site infection incidence ranged from 3.2 to 27.6%. Two out of five studies evaluating hospital size adjusted the analysis to patient and procedure-related risk factors, and showed that larger hospitals were either positively associated or had no association with SSI. Public hospitals did not present significantly different infection rates than private or non-profit ones. Medical school affiliation and higher safety-net burden were associated with higher surgical site infection (crude estimates), while oncological hospitals were associated with higher incidence independently of other variables. Hospital caseload showed mixed results, while surgeon caseload and surveillance time since implementation appear to be associated with fewer infections. Conclusions: Although there are few studies addressing hospital-level factors on surgical site infection, surgeon experience and the implementation of a surveillance system appear to be associated with better outcomes. For hospitals and services to be efficiently optimized, more studies addressing these variables are needed that take into account the confounding effect of patient case mix.The Epidemiology Research Unit (EPIUnit, Unidade de Investigação em Epidemiologia—Instituto de Saúde Pública da Universidade do Porto) is funded by the Portuguese Foundation for Science and Technology (POCI-01-0145-FEDER-006862; Ref. ()

Tensor coupling and pseudospin symmetry in nuclei

In this work we study the contribution of the isoscalar tensor coupling to the realization of pseudospin symmetry in nuclei. Using realistic values for the tensor coupling strength, we show that this coupling reduces noticeably the pseudospin splittings, especially for single-particle levels near the Fermi surface. By using an energy decomposition of the pseudospin energy splittings, we show that the changes in these splittings come by mainly through the changes induced in the lower radial wave function for the low-lying pseudospin partners, and by changes in the expectation value of the pseudospin-orbit coupling term for surface partners. This allows us to confirm the conclusion already reached in previous studies, namely that the pseudospin symmetry in nuclei is of a dynamical nature.Comment: 11 pages, 5 figures, uses REVTeX macro

Determination of the neutron star mass-radii relation using narrow-band gravitational wave detector

The direct detection of gravitational waves will provide valuable astrophysical information about many celestial objects. The most promising sources of gravitational waves are neutron stars and black holes. These objects emit waves in a very wide spectrum of frequencies determined by their quasi-normal modes oscillations. In this work we are concerned with the information we can extract from f and p$_I$-modes when a candidate leaves its signature in the resonant mass detectors ALLEGRO, EXPLORER, NAUTILUS, MiniGrail and SCHENBERG. Using the empirical equations, that relate the gravitational wave frequency and damping time with the mass and radii of the source, we have calculated the radii of the stars for a given interval of masses $M$ in the range of frequencies that include the bandwidth of all resonant mass detectors. With these values we obtain diagrams of mass-radii for different frequencies that allowed to determine the better candidates to future detection taking in account the compactness of the source. Finally, to determine which are the models of compact stars that emit gravitational waves in the frequency band of the mass resonant detectors, we compare the mass-radii diagrams obtained by different neutron stars sequences from several relativistic hadronic equations of state (GM1, GM3, TM1, NL3) and quark matter equations of state (NJL, MTI bag model). We verify that quark stars obtained from MIT bag model with bag constant equal to 170 MeV and quark of matter in color-superconductivity phase are the best candidates for mass resonant detectors.Comment: 10 pages and 3 figure

Charge Influence On Mini Black Hole's Cross Section

In this work we study the electric charge effect on the cross section production of charged mini black holes (MBH) in accelerators. We analyze the charged MBH solution using the {\it fat brane} approximation in the context of the ADD model. The maximum charge-mass ratio condition for the existence of a horizon radius is discussed. We show that the electric charge causes a decrease in this radius and, consequently, in the cross section. This reduction is negligible for protons and light ions but can be important for heavy ions.Comment: 4 pages, 0 figure. To be published in Int. J. Mod. Phys. D

Ecologia da polinização do feijão-caupi (Vigna ungulculata (L.) walp.) em área de sequeiro no municipio de Petrolina-PE.

o feijão-caupi é uma leguminosa de origem africana de importante papel como fonte alimentarpara as regiõestropicais e subtropicaisdo mundo

Effect of sodium hypochlorite on bacteria isolated from drinking water

Biofilm formation inside drinking water distribution systems (DWDS) constitutes one of the major microbial problems in the distribution of safe water. Biofilms in DWDS can act as a reservoir of pathogenic microorganisms and consequently constitute a threat to public health. Therefore, the control of biofilm development inside the pipes of DWDS is a concern for drinking water companies being the use of chlorine one of the most commonly used disinfecting strategies to avoid microbial growth. The aim of this work was to understand the effects of sodium hypochlorite (NaOCl) at residual and high doses against biofilms formed by two bacteria isolated from a DWDS (Acinectobacter calcoaceticus and Stenotrophomonas maltophilia, two emergent pathogens) on polyvinyl chloride. The NaOCl effects were evaluated in bacterial membrane properties and in biofilm cohesion. NaOCl demonstrated action on the bacterial membrane, particularly on the surface hydrophobicity of A. calcoaceticus and on the surface charge of S. maltophilia. NaOCl also caused motility inhibition of A. calcoaceticus. The use of residual concentrations to control bacterial adhesion was inefficient. High concentrations were able to reduce significantly the number of adhered bacteria. However, mature biofilms formed by A. calcoaceticus and S. maltophilia were highly resistant to the combination of chemical and mechanical stresses. In conclusion, the overall results demonstrated a significant action of NaOCl on A. calcoaceticus and S. maltophilia planktonic cells and monolayer adhered cells. However, their mature biofilms were not controlled even when high biocide doses and mechanical stress were applied alone and in combination

Uma experiência presidencialista em Portugal, 1917-1918

É mais ou menos consensual na moderna historiografia portuguesa aceitar como conjuntura histórica o período que vai de 1890 a 1926. Um período balizado por dois acontecimentos marcantes: a entrega, a 11 de Janeiro, do célebre memorandum do Governo britânico como resposta à tentativa de Portugal ocupar as regiões compreendidas entre Angiola e Moçambique (o chamado mapa cor-de-rosa), que provocou uma fortíssima crise política e uma enorme indignação social de cunho nacionalista explorada habilmente pelo Partido Republicano Português; e o golpe miliar de 28 de Maio de 1926, epílogo quase inevitável de dezasseis anos de atribuladíssima aventura utópica demo-republicana, e "fundador" de um regime ditatorial (émulo nos anos trinta do fascismo europeu) que, com várias nuances político-institucionais e sócio-económicas, se prolongaria até 25 de Abril de 1974

Comparison of the efficacy of natural-based and synthetic biocides to disinfect silicone and stainless steel surfaces

New biocidal solutions are needed to combat effectively the evolution of microbes developing antibiotic resistance while having a low or no environmental toxicity impact. This work aims to assess the efficacy of commonly used biocides and natural-based compounds on the disinfection of silicone and stainless steel (SS) surfaces seeded with different Staphylococcus aureus strains. Minimum inhibitory concentration was determined for synthetic (benzalkonium chloride-BAC, glutaraldehyde-GTA, ortho-phthalaldehyde-OPA and peracetic acid-PAA) and natural-based (cuminaldehyde-CUM), eugenol-EUG and indole-3-carbinol-I3C) biocides by the microdilution method. The efficacy of selected biocides at MIC, 10×MIC and 5500 mg/L (representative in-use concentration) on the disinfection of sessile S. aureus on silicone and SS was assessed by viable counting. Silicone surfaces were harder to disinfect than SS. GTA, OPA and PAA yielded complete CFU reduction of sessile cells for all test concentrations as well as BAC at 10×MIC and 5500 mg/L. CUM was the least efficient compound. EUG was efficient for SS disinfection, regardless of strains and concentrations tested. I3C at 10×MIC and 5500 mg/L was able to cause total CFU reduction of silicone and SS deposited bacteria. Although not so efficient as synthetic compounds, the natural-based biocides are promising to be used in disinfectant formulations, particularly I3C and EUG