5-nitro-thiophene-thiosemicarbazone derivative induces cell death, cell cycle arrest, and phospho-kinase shutdown in pancreatic ductal adenocarcinoma cells.

Introduction: Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive cancer with limited treatment options. This study explores the potential of novel 5-nitro-thiophene-thiosemicarbazone derivatives as therapeutic agents for PDAC.

Methods: We evaluated the cytotoxicity of seven derivatives in peripheral blood mononuclear cells (PBMCs) and PDAC cell lines.

Evaluation of Thiazolidine Derivatives with Potential Anti-ZIKV Activity.

Objective: In this study, we have synthesized 19 Thiazolidine (TZD) derivatives to investigate their potential anti-ZIKV effects.

Methods: Nineteen thiazolidine derivatives were synthesized and evaluated for their cytotoxicity and antiviral activity against the ZIKA virus.

Results: Among them, six demonstrated remarkable selectivity against the ZIKV virus, exhibiting IC50 values of <5μM, and the other compounds did not demonstrate selectivity for the virus.

Altered brain connectivity during visual stimulation in schizophrenia.

Schizophrenia (SCZ) can be described as a functional dysconnectivity syndrome that affects brain connectivity and circuitry. However, little is known about how sensory stimulation modulates network parameters in schizophrenia, such as their small-worldness (SW) during visual processing. To address this question, we applied graph theory algorithms to multi-electrode EEG recordings obtained during visual stimulation with a checkerboard pattern-reversal stimulus.

Evaluation of long-term stability of SARS-CoV-2 nucleic acid extracted from human nasopharyngeal samples.

The maintenance of SARS-Cov-2 RNA samples poses a new challenge for laboratories and researchers. In addition, it is a requirement in order to identify what strain of the new coronavirus is predominant in a region, for instance. Therefore, it is a must to keep the quality and viability of stored RNA to respond to this and other valid questions.

2048-QAM transmission at 15 GBd over 100 km using geometric constellation shaping.

We experimentally investigated a pilot-aided digital signal processing (DSP) chain in combination with high-order geometric constellation shaping to increase the achievable information rates (AIRs) in standard intradyne coherent transmission systems. We show that the AIR of our system at 15 GBd was maximised using geometrically-shaped (GS) 2048 quadrature amplitude modulation (QAM), reaching 18.0 b/4D-symbol in back-to-back transmission and 16.

Distributed abstraction and verification of an installed optical fibre network.

The management of wavelength routed optical mesh networks is complex with many potential light path routes and numerous physical layer impairments to transmission performance. This complexity can be reduced by applying the ideas of abstraction from computer science where different equipment is described in the same basic terms. The noise-to-signal ratio can be used as a metric to describe the quality of transmission performance of a signal propagated through a network element and accumulates additively through a sequence of such elements allowing the estimation of end-to-end performance.

Antifungal effects of the flavonoids kaempferol and quercetin: a possible alternative for the control of fungal biofilms.

This study aimed to determine the minimum inhibitory concentration (MIC) of kaempferol and quercetin against planktonic and biofilm forms of the complex. Initially, nine , nine and nine strains were used. Planktonic susceptibility to kaempferol and quercetin was assessed.

Experimental characterization of nonlinear interference noise as a process of intersymbol interference.

We demonstrate a method for experimentally characterizing the second order statistics of nonlinear interference noise (NLIN) as an intersymbol interference (ISI) process. The method enables measurement of the properties of high-order ISI coefficients, which have been largely overlooked in the past. The ability of measuring these statistics is imperative for designing effective NLIN mitigation schemes.

Investigation of bandwidth loading in optical fibre transmission using amplified spontaneous emission noise.

The use of spectrally shaped amplified spontaneous emission noise (SS-ASE) as a method for emulating interfering channels in optical fibre transmission systems has been studied. It is shown that the use of SS-ASE leads to a slightly pessimistic performance relative to the use of conventionally modulated interfering channels in the nonlinear regime. The additional nonlinear interference noise (on the channel under test), due to the Gaussian nature of SS-ASE, has been calculated using a combination of the Gaussian noise (GN) and enhanced GN (EGN) models for the entire C-band (4.

Impact of pollution on the microbial diversity of a tropical river in an urbanized region of northeastern Brazil.

Rivers are important ecosystems that are integrated into biogeochemical cycles and constitute an essential resource for numerous human uses. However, the assessment of the biological diversity and composition of microbial communities found in rivers remains incomplete, partly due to methodological constraints which are only recently being resolved with the advent of next generation sequencing (NGS) techniques. Using 454-pyrosequencing of the 16S gene, the present study analyzed the microbial diversity of the planktonic and sediment populations in a tropical river in northeastern Brazil that is exposed to severe pollution.

Digital back-propagation for nonlinearity mitigation in distributed Raman amplified links.

The performance of digital back-propagation (DBP) for distributed Raman amplified optical communication systems is evaluated through analytical models and numerical simulations, and is compared with conventional lumped amplifier solutions, such as EDFA. The complexity of the DBP algorithm including the characteristic signal power profile of distributed Raman amplifiers is assessed. The use of full-field DBP in distributed Raman amplified systems leads to 1.

On the limits of digital back-propagation in the presence of transceiver noise.

This paper investigates the impact of transceiver noise on the performance of digital back-propagation (DBP). A generalized expression to estimate the signal-to-noise ratio (SNR) obtained using DBP in the presence of transceiver noise is described. This new expression correctly accounts for the nonlinear beating between the transceiver noise and the signal in the optical fiber transmission link.

On the bandwidth dependent performance of split transmitter-receiver optical fiber nonlinearity compensation.

The Gaussian noise model is used to estimate the performance of three digital nonlinearity compensation (NLC) algorithms in C-band, long-haul, optical fiber transmission, when the span length and NLC bandwidth are independently varied. The algorithms are receiver-side digital backpropagation (DBP), transmitter-side DBP (digital precompensation), and Split NLC (an equal division of DBP between transmitter and receiver). For transmission over 100×100 km spans, the model predicts a 0.

Comparison of digital signal-signal beat interference compensation techniques in direct-detection subcarrier modulation systems.

Single-polarization direct-detection transceivers may offer advantages compared to digital coherent technology for some metro, back-haul, access and inter-data center applications since they offer low-cost and complexity solutions. However, a direct-detection receiver introduces nonlinearity upon photo detection, since it is a square-law device, which results in signal distortion due to signal-signal beat interference (SSBI). Consequently, it is desirable to develop effective and low-cost SSBI compensation techniques to improve the performance of such transceivers.

High spectral density transmission emulation using amplified spontaneous emission noise.

We demonstrate the use of spectrally shaped amplified spontaneous emission (SS-ASE) noise for wideband channel loading in the investigation of nonlinear transmission limits in wavelength-division multiplexing transmission experiments using Nyquist-spaced channels. The validity of this approach is explored through statistical analysis and experimental transmission of Nyquist-spaced 10 GBaud polarization-division multiplexing (PDM) quadrature phase-shift keying and PDM-16-ary quadrature amplitude modulation (QAM) channels, co-propagated with SS-ASE over single mode fiber. It is shown that this technique, which is simpler to implement than a fully modulated comb of channels, is valid for distances exceeding 240 km for PDM-16QAM with dispersion of 16 ps/nm/km, yields a good agreement with theory, and provides a conservative measure of system performance.

Differences in physiological traits associated with water balance among rodents, and their relationship to tolerance of habitat fragmentation.

Physiological concepts and tools can help us to understand why organisms and populations respond to habitat fragmentation in the way they do, and allow us to determine the mechanisms or individual characteristics underlying this differential sensitivity. Here, we examine food intake, relative medullary thickness and distribution/expression of water channel aquaporin-1 in three species of South American rodents that have been reported to have different levels of tolerance to habitat fragmentation (Akodon montensis, Oligoryzomys nigripes, and Euryoryzomys russatus), using a classic water deprivation experiment to assess their abilities to cope with water shortage. We believe the mechanisms underlying this differential sensitivity are related to the organisms' capacities to maintain water balance, and therefore the species more tolerant to habitat fragmentation (A.

Unrepeatered Nyquist PDM-16QAM transmission over 364 km using Raman amplification and multi-channel digital back-propagation.

Transmission of a net 467-Gb/s PDM-16QAM Nyquist-spaced superchannel is reported with an intra-superchannel net spectral efficiency (SE) of 6.6 (b/s)/Hz, over 364-km SMF-28 ULL ultra-low loss optical fiber, enabled by bi-directional second-order Raman amplification and digital nonlinearity compensation. Multi-channel digital back-propagation (MC-DBP) was applied to compensate for nonlinear interference; an improvement of 2 dB in Q(2) factor was achieved when 70-GHz DBP bandwidth was applied, allowing an increase in span length of 37 km.

Spectrally shaped DP-16QAM super-channel transmission with multi-channel digital back-propagation.

The achievable transmission capacity of conventional optical fibre communication systems is limited by nonlinear distortions due to the Kerr effect and the difficulty in modulating the optical field to effectively use the available fibre bandwidth. In order to achieve a high information spectral density (ISD), while simultaneously maintaining transmission reach, multi-channel fibre nonlinearity compensation and spectrally efficient data encoding must be utilised. In this work, we use a single coherent super-receiver to simultaneously receive a DP-16QAM super-channel, consisting of seven spectrally shaped 10GBd sub-carriers spaced at the Nyquist frequency.

Experimental demonstration of 30 Gb/s direct-detection optical OFDM transmission with blind symbol synchronisation using virtual subcarriers.

The paper investigates the performance of a blind symbol synchronisation technique for optical OFDM systems based on virtual subcarriers. The test-bed includes a real-time 16-QAM OFDM transmitter operating at a net data rate of 30.65 Gb/s using a single OFDM band with a single FPGA-DAC subsystem and demonstrates transmission over 23.

Effects of a type I antifreeze protein (AFP) on the melting of frozen AFP and AFP+solute aqueous solutions studied by NMR microimaging experiment.

The effects of a type I AFP on the bulk melting of frozen AFP solutions and frozen AFP+solute solutions were studied through an NMR microimaging experiment. The solutes studied include sodium chloride and glucose and the amino acids alanine, threonine, arginine, and aspartic acid. We found that the AFP is able to induce the bulk melting of the frozen AFP solutions at temperatures lower than 0 °C and can also keep the ice melted at higher temperatures in the AFP+solute solutions than those in the corresponding solute solutions.

Clinical and functional capacity of patients with dilated cardiomyopathy after four years of transplantation.

Objective: To evaluate patient with cardiomyopathy's progress after cardiac transplant, by analyzing his survival, complications and cardiovascular responses after nearly four years of surgery.

Methods: The survey was conducted from February to May 2011, with patients undergoing cardiac transplantation at Dr. Carlos Alberto Studart Gomes Hospital - Messejana Hospital (HDM).

Niche for acridine derivatives in anticancer therapy.

During the last 4 decades, intensive research has focussed on the effect of small organic molecules with antitumour activity that are able to intercalate into DNA and inhibit topoisomerase and telomerase enzymes. In this review, we describe some of the chemical and biological properties of acridine, which is a chemotherapeutic agent that has been used for cancer treatment since 1970. In addition, we summarise the progress that has been made in the development of anticancer agents based on the clinical in vivo/in vitro studies that have been conducted for 13 classes of natural and synthetic acridines.

Substituted thiazolidinediones and thio-imidazolidinones: synthesis, structural study and pharmacological activity.

Synthesis and physico-chemical properties of six 3-(4-bromophenacyl)-5-arylidene-thiazolidine-2,4-diones and eight 3-(4-chlorobenzyl)-5-arylidene-4-thio-imidazolidine-2-ones are described. These products were synthesized by an aldolisation-crotonisation reaction from aromatic aldehydes and 3-substituted thiazolidine-2,4-diones or 4-thio-imidazolidine-2-ones. Hypoglycemic and peripheral antinociceptive activities were investigated for these compounds.