Blocked-braid Groups

We introduce and study a family of groups $\mathbf{BB}_n$, called the blocked-braid groups, which are quotients of Artin's braid groups $\mathbf{B}_n$, and have the corresponding symmetric groups $\Sigma_n$ as quotients. They are defined by adding a certain class of geometrical modifications to braids. They arise in the study of commutative Frobenius algebras and tangle algebras in braided strict monoidal categories. A fundamental equation true in $\mathbf{BB}_n$ is Dirac's Belt Trick; that torsion through $4\pi$ is equal to the identity. We show that $\mathbf{BB}_n$ is finite for $n=1,2$ and 3 but infinite for $n>3$

A General Recurrent Neural Network Approach to Model Genetic Regulatory Networks

There is an urgent need for tools to unravel the complex interactions and functionalities of genes. As such, there has been much interest in reverse-engineering genetic regulatory networks from time series gene expression data. We use an artificial neural network to model the dynamics of complicated gene networks and to learn their parameters. The positive and negative regulations of genes are defined by a weight matrix, and different genes are allowed to have different decaying time constants. We demonstrate the effectiveness of the method by recreating the SOS DNA Repair network of Escherichia coli bacterium, previously discovered through experimental data

Ignition and reaction mechanism of Co-Al and Nb-Al intermetallic compounds prepared by combustion synthesis

The ignition and propagation mechanism of the self-propagating high-temperature synthesis of several cobalt and niobium aluminides was investigated. Two propagation mechanisms were identified depending on the stoichiometry of the starting mixture. Al-rich compositions propagate through a dissolution-precipitation mechanism while Al-poor mixtures require solid state diffusion. The ignition temperatures were measured by means of microthermocouples in quasi-adiabatic conditions through experiments carried out in thermal explosion mode. Ignition temperatures were found to be characteristic of each system and to depend strongly on reactants particle size. Ignition energies for all compositions were evaluated through a mathematical model

Efficacy and Safety of Axiostat® Hemostatic Dressing in Aiding Manual Compression Closure of the Femoral Arterial Access Site in Patients Undergoing Endovascular Treatments: A Preliminary Clinical Experience in Two Centers

Background: Hemostasis of the femoral arterial access site by manual compression or a vascular closure device is critical to the safe completion of any endovascular procedure. Previous investigations evaluated the hemostatic efficacy at the radial access site of some chitosan-based hemostatic pads. This study aims to assess the efficacy and safety of a new chitosan-based hemostatic dressing, namely Axiostat®, in aiding manual compression closure of the femoral arterial access site in patients undergoing endovascular treatments. Furthermore, the outcomes were compared with evidence on manual compression alone and vascular closure devices. Methods: This investigation is a two-center retrospective analysis of 120 consecutive patients who had undergone, from July 2022 to February 2023, manual compression closure of the femoral arterial access site aided by the Axiostat® hemostatic dressing. Endovascular procedures performed with introducer sheaths ranging from 4 Fr to 8 Fr were evaluated. Results: Primary technical success was achieved in 110 (91.7%) patients, with adequate hemostasis obtained in all cases of prolonged manual compression requirements. The mean time-to-hemostasis and time-to-ambulation were 8.9 (±3.9) and 462 (±199) minutes, respectively. Clinical success was achieved in 113 (94.2%) patients, with bleeding-related complications noted in 7 (5.8%) patients. Conclusions: Manual compression aided by the Axiostat® hemostatic dressing is effective and safe in achieving hemostasis of the femoral arterial access site in patients undergoing endovascular treatment with a 4–8 Fr introducer sheath

Protein identification by nanopore peptide profiling

Nanopores are single-molecule sensors used in nucleic acid analysis, whereas their applicability towards full protein identification has yet to be demonstrated. Here, we show that an engineered Fragaceatoxin C nanopore is capable of identifying individual proteins by measuring peptide spectra that are produced from hydrolyzed proteins. Using model proteins, we show that the spectra resulting from nanopore experiments and mass spectrometry share similar profiles, hence allowing protein fingerprinting. The intensity of individual peaks provides information on the concentration of individual peptides, indicating that this approach is quantitative. Our work shows the potential of a low-cost, portable nanopore-based analyzer for protein identification.</p

Protein identification by nanopore peptide profiling

Nanopores are single-molecule sensors used in nucleic acid analysis, whereas their applicability towards full protein identification has yet to be demonstrated. Here, we show that an engineered Fragaceatoxin C nanopore is capable of identifying individual proteins by measuring peptide spectra that are produced from hydrolyzed proteins. Using model proteins, we show that the spectra resulting from nanopore experiments and mass spectrometry share similar profiles, hence allowing protein fingerprinting. The intensity of individual peaks provides information on the concentration of individual peptides, indicating that this approach is quantitative. Our work shows the potential of a low-cost, portable nanopore-based analyzer for protein identification

Quantitative assessment of HCC wash-out on CT is a predictor of early complete response to TACE

OBJECTIVES: To investigate the predictive value of four-phase contrast-enhanced CT (CECT) for early complete response (CR) to drug-eluting-bead transarterial chemoembolization (DEB-TACE), with a particular focus on the quantitatively assessed wash-in and wash-out. METHODS: A retrospective analysis of preprocedural CECTs was performed for 129 HCC nodules consecutively subjected to DEB-TACE as first-line therapy. Lesion size, location, and margins were recorded. For the quantitative analysis, the following parameters were computed: contrast enhancement ratio (CER) and lesion-to-liver contrast ratio (LLC) as estimates of wash-in; absolute and relative wash-out (WO(abs) and WO(rel)) and delayed percentage attenuation ratio (DPAR) as estimates of wash-out. The early radiological response of each lesion was assessed by the mRECIST criteria and dichotomized in CR versus others (partial response, stable disease, and progressive disease). RESULTS: All quantitatively assessed wash-out variables had significantly higher rates for CR lesions (WO(abs) p = 0.01, WO(rel) p = 0.01, and DPAR p = 0.00002). However, only DPAR demonstrated an acceptable discriminating ability, quantified by AUC = 0.80 (95% CI0.73–0.88). In particular, nodules with DPAR ≥ 120 showed an odds ratio of 3.3(1.5–7.2) for CR (p = 0.0026). When accompanied by smooth lesion margins, DPAR ≥ 120 lesions showed a 78% CR rate at first follow-up imaging. No significative association with CR was found for quantitative wash-in estimates (CER and LLC). CONCLUSIONS: Based on preprocedural CECT, the quantitative assessment of HCC wash-out is useful in predicting early CR after DEB-TACE. Among the different formulas for wash-out quantification, DPAR has the best discriminating ability. When associated, DPAR ≥ 120 and smooth lesion margins are related to relatively high CR rates. KEY POINTS: • A high wash-out rate, quantitatively assessed during preprocedural four-phase contrast-enhanced CT (CECT), is a favorable predictor for early radiological complete response of HCC to drug-eluting-bead chemoembolization (DEB-TACE). • The arterial phase of CECT shows great dispersion of attenuation values among different lesions, even when a standardized protocol is used, limiting its usefulness for quantitative analyses. • Among the different formulas used to quantify the wash-out rate (absolute wash-out, relative wash-out, and delayed percentage attenuation ratio), the latter (DPAR), based only on the delayed phase, is the most predictive (AUC = 0.80), showing a significant association with complete response for values above 120

Effect of butanol and salt concentration on solid-state nanopores resistance

The objective of this study was to demonstrate the possibility of using 1-butanol to detect in a reliable way the open pore current of pyramidal solid-state nanopores produced in silicon wafers. The nanopores were produced through controlled pore formation by neutralizing an etchant (KOH) with a strong acid (HCl). Since nanopores produced by this method have a larger depth than those made in nanometer thick membranes, they behave as nanochannels. As a consequence, the open pore current detection is more challenging. Thus, we report that low amounts of butanol considerably aid in the detection of the open pore current of nanopores.Fil: Vega, M.. Universidad Tecnológica Nacional. Facultad Regional Haedo; ArgentinaFil: Perez, Maximiliano Sebastian. Universidad Tecnológica Nacional. Facultad Regional Haedo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Granell, Pablo Nicolás. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Golmar, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Wloka, C.. University of Groningen; Países BajosFil: Maglia, G.. University of Groningen; Países BajosFil: Dieguez, M.J.. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Del Valle, E.M.. Universidad de Salamanca; EspañaFil: Lasorsa, Carlos Alberto. Universidad Tecnológica Nacional. Facultad Regional Haedo; ArgentinaFil: Lerner, Betiana. Universidad Tecnológica Nacional. Facultad Regional Haedo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin