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This letter investigates user fairness in wireless powered communication networks (WPCNs) with non-orthogonal multiple access (NOMA) with the aim of maximizing the equal individual data rates. Initially, it is proposed the bisection method to obtain the optimal power allocation coefficients. Then, Lagrange dual-decomposition is considered for evaluating the optimal time-splitting ratio. Next, Newton’s method combined with the sub-gradient method are employed to achieve the optimal solution. In addition, two sub-optimal solutions that provide a good balance between performance and complexity are proposed. Lastly, simulation results are presented to evaluate the performance of the proposed solutions.

In this letter, we investigate closed-form distributions to approximate the power of the residual Self-Interference (SI) due to: 1) uncanceled signals transmitted over multiple delay-taps, and 2) the presence of radio frequency and transceiver impairments, of an In-Band Full-duplex (IBFDX) wireless system. Starting with the distribution of the residual SI power for a single tap, we extend the analysis for multiple taps comparing two different solutions. The first one is based on the Welch-Satterthwaite (W-S) approximation, while the second is a moment-based approximation to an $\alpha $ - $\mu $ distribution. When compared to empirical results obtained by simulation, our work shows that the distribution of the residual SI power can be accurately represented by the W-S approximation when the uncertainty level of the fading in the different taps is low. However, for higher levels of uncertainty we show that the $\alpha $ - $\mu $ moment-based approximation is more accurate. A comparison between simulated and numerical results show the effectiveness of the proposed model.

ABSTRACTThe Brazilian Oceanographic Modeling and Observation Network (REMO, acronym for ‘Rede de Modelagem e Observação Oceanográfica’ in Portuguese) has developed the REMO Ocean Data Assimilation System (RODAS). It is based on an Ensemble Optimal Interpolation scheme applied into the Hybrid Coordinate Ocean Model (HYCOM). This study aims to investigate the extended-range predictability of the HYCOM + RODAS System over the western South Atlantic by using its analyses as initial condition for 48 hindcasts, each covering 30 days. The outputs were compared to persistence (no change from the initial condition) and to a model free run. The hindcasts had the lowest root mean square difference (RMSD) and highest correlation of sea surface temperature (SST) and sea level anomaly (SLA) at all lead times. By the 30th day, persistence RMSD reached 1.09°C and 0.08 m for SST and SLA, respectively, while the hindcast RMSD reached 0.46°C and 0.05 m. The free run RMSD was almost constant with an average of 0.88°C and 0.13 m. In the subsurface, hindcast RMSD increase was even lower. The results suggest that HYCOM + RODAS predictive skill extends for more than a month and the thermohaline state of the ocean was consistently improved with respect to the free model run.

In this letter, a new general composite fading model, namely $\alpha $ - $\eta $ - $\kappa $ - $\mathcal {F}$ model, is proposed. It considers most of the well-known propagation phenomena in wireless fading channels, such as shadowing, multi-path fading, non-linearity of the propagation medium, power of the dominant components, and power of the scattered waves. Additionally, most of the important statistical fading models are included in the $\alpha $ - $\eta $ - $\kappa $ - $\mathcal {F}$ model as special cases. The envelope probability density function (PDF) and cumulative distribution function (CDF) are derived and then employed to derive the PDF and CDF of the instantaneous signal-to-noise ratio. The performance of a wireless communication system operating under the $\alpha $ - $\eta $ - $\kappa $ - $\mathcal {F}$ composite model is evaluated in terms of outage probability and symbol error rate. Numerical results are supported by Monte-Carlo simulations to validate the analysis.

We performed simulations and experiments of wavefront distortions induced by propagating through diode-pumped square-section amplifying laser rods of Nd-doped phosphate glass and 0.5%Nd:5%Lu:CaF_2. We observed that depending on the material, wavefront distortions’ profile can vary from a circular lens-like distortion to a complex astigmatic distortion. We showed that this difference comes from the relative sign of piezo-optic tensor coefficients.

Neglected tropical diseases are a serious global public health problem and they are one of the main causes of mortality and morbidity, especially in underdeveloped countries. These diseases have several implications for health and they are considered a priority in global eradication programs for disease control. The aim of this mini-review is to report recent studies on the fight against neglected diseases, namely dengue fever, chikungunya, zika, malaria protozoa, Chagas disease, leishmaniasis, schistosomiasis helminths, filariasis, and tuberculosis bacteria using extracts and isolated substances of endophytic fungi based on their bioactivity profiles in relation to these diseases.

Theranostics in nuclear medicine, the pairing of diagnostic and therapeutic agents to target diseased cells and tissue, can help customize the management of various diseases and predict treatment response and toxicity and is emerging as an essential component in the practice of personalized medicine.

In this work, the lanthanide (Ln) contraction phenomenon has been analyzed for three-dimensional structures in the solid state. We chose to study an isostructural series of lanthanide organic frameworks (LOFs) of formula [Ln2(C4H4O4)3(H2O)2]n·H2O and 14 crystallographic structures (except promethium complex). The analysis of Ln contraction was made by analyzing the sum of all Ln–O bond lengths and the sum of all O–O distances, for the oxygen atoms of the coordination polyhedra, calculated with different semiempirical quantum mechanical models. The ∑Ln–Oand ∑O–Ofor this LOF can be fit to a second-order polynomial. Based on the crystallographic structures, it is concluded that the phenomenon of Ln contraction is observed. Our results also suggest that the semiempirical Sparkle/PM3 and Sparkle/RM1 models reproduce the Ln contraction phenomenon well, and similar fits were obtained for ∑Ln–Oand ∑O–Obond lengths.

PSMA PET for assessing therapy response in metastatic prostate cancer, a challenging and relatively underexplored scenario, can provide valuable information and impact care in clinical situations such as biochemical recurrence, high-risk primary disease staging, and castration-resistant disease.

This letter studies the resource allocation problem of sum rate maximization in wireless powered communication networks (WPCNs) with non-orthogonal multiple access (NOMA) that satisfy minimum data rate requirements per user. Firstly, we derive closed-form solutions for the time-splitting ratio and power allocation coefficients that maximize the approximated sum rate NOMA expression. Then, we use the solution of the approximated problem as the starting point for solving the original problem through Newton’s method. Simulation results show the effectiveness of the proposed approximation as well as the fast convergence of the optimal solution.

The elucidation of the action of doxorubicin (DOX) has been considered a challenge for cancer therapy. Using theoretical approaches, we investigated the structure and electronic properties of DOX as a function of pH, which we thought likely to be related to the influence of its tautomers. Regarding the relative stabilities among the tautomers, the results obtained from PM6 were the most similar to those obtained from DFT. The theoretical absorption spectrum for each tautomeric species simply showed a single absorption peak located around 400 nm, in contrast to the experimental absorption spectra in the literature that showed four absorption bands. The experimental evidence was properly explained by considering four tautomeric conformers of DOX. The spectroscopic study of the deprotonated tautomers also suggested the presence of four deprotonated tautomers at more basic pH values. The spectrum at pH 10.08 can be explained by the presence of protonated and deprotonated doxorubicin species.

IntroductionImproved functional outcomes after mechanical thrombectomy for emergent large vessel occlusion depend on expedient reperfusion after clinical presentation. Device technology has improved substantially over the years, and several commercial options exist for both large-bore aspiration catheters and suction pump systems.ObjectiveTo compare various vacuum pumps and examine the aspiration forces they generate as well as the force of catheter tip detachment from an artificial thrombus.MethodsUsing an artificial thrombus made from polyvinyl alcohol gel, we tested various mechanical characteristics of commercially available suction pumps, including the Penumbra Jet Engine, Penumbra Max, Stryker Medela AXS, Microvention Gomco, and a 60 cc syringe. Both aspiration pressure and tip force generated were analyzed. Subsequently, a cohort of thrombectomy catheters were assessed using the Penumbra Jet Engine to determine tip forces generated on an artificial thrombus. One-way analysis of variance was used to assess statistical significance.ResultsThe Penumbra Jet Engine system generated both the highest maximum aspiration pressures (28.8 inches Hg) and the highest tip force (23.68 grams force (gf)) on an artificial thrombus, with statistical significance compared with the other pump systems. Using the Jet Engine, the largest-bore catheter was associated with the highest tip force (32.12 gf). The overall correlation coefficient between catheter inner diameter and tip force was 0.98.ConclusionsThe Penumbra Jet Engine pump generates significantly higher vacuum pressures and tip forces than the other commercially available aspiration pump systems. Furthermore, catheters with a larger inner diameter generate higher tip suction forces on aspiration. Whether these mechanical features lead to improved clinical outcomes is yet to be determined.

The bacterium Rickettsia rickettsiiis the agent of Brazilian spotted fever (BSF), a highly fatal disease that is transmitted in Brazil mainly by the tick Amblyomma sculptumBerlese, which uses capybaras (Hydrochoerus hydrochaerisLinnaeus) as major hosts. In 2015, we captured nine capybaras in a BSF-endemic area of southeastern Brazil. From each capybara, we collected blood sera that were tested through the immunofluorescence assay using Rickettsiaspp. antigens, and A. sculptumticks, processed for isolation of R. rickettsiithrough guinea pig inoculation. All capybaras (100%) were seroreactive to Rickettsiaspp., with highest titers to R. rickettsii. A total of 166 A. sculptumticks were macerated and inoculated into nine guinea pigs, from which only one presented high fever and seroconverted to R. rickettsii. Blood from this febrile animal was inoculated into additional guinea pigs (guinea pig passages), which also became febrile and seroconverted, or when euthanized during the fever period, their internal organs (spleen, lung) were shown to contain R. rickettsiiDNA. The present rickettsial isolate has been maintained cryopreserved as infected guinea pig organs. There was at least one R. rickettsii-infected tick among the 166 macerated ticks, giving a minimal infection rate of 0.6% (1/166). This infection rate is within the range of previous studies, which reported that only 0.05% to at most 1.28% A. sculptumticks were infected by R. rickettsiiin other BSF-endemic areas. These low infection rates support the low incidence of BSF, despite of A. sculptumbeing the most frequent human-biting tick in southeastern Brazil.

Massive multiple-input multiple-output (MIMO) and non-orthogonal multiple access (NOMA) are two key techniques for enabling massive connectivity in future wireless networks. A massive MIMO-NOMA system can deliver remarkable spectral improvements and low communication latency. Nevertheless, the uncontrollable stochastic behavior of the wireless channels can still degrade its performance. In this context, the idea of an intelligent reflecting surface (IRS) has emerged as a promising technology for smartly overcoming the possibly detrimental effects of the wireless environment. The disruptive IRS concept of controlling the propagation channels via software can provide attractive performance gains to the communication networks, including higher data rates, improved user fairness, and possibly higher energy efficiency. In this article, we demonstrate the main roles of IRSs in MIMO-NOMA systems. Specifically, we identify key challenges and perform a comprehensive discussion of the main performance gains that can be achieved in IRS-assisted massive MIMO-NOMA (IRS-NOMA) networks. We outline exciting futuristic use case scenarios for IRS-NOMA and expose the main related challenges and future research directions. Furthermore, throughout the article, we support our in-depth discussions with representative numerical results.

In this letter, we investigate the impact of wireless-powered communications when energy is harvested from multiple static and/or mobile wireless coexisting networks. In a first step, we characterize the aggregate power received by a harvester node when it harnesses the energy generated by the coexisting wireless networks. Considering that the harvester node acts as a transmitter after the harvesting duration, we derive the outage probability for such coexisting scenario. In addition, the throughput achieved by the harvester node is also characterized, and the optimal harvesting duration is identified taking into account the mobility of the coexisting networks, the features of the static networks, the energy harvesting process, as well as the communication performance between the harvester node and the receiver. This letter shows that the distribution of the power received by the harvester from the coexisting networks can be accurately approximated by an $\alpha -\mu $ distribution. Moreover, the mobility also impacts on the optimal throughput of the wireless-powered communications, which is accurately confirmed by the proposed analysis and extensive simulations.

Systemic treatment of metastatic adrenocortical carcinoma (ACC) remains limited to chemotherapy and mitotane. Preliminary evidence suggesting that antitumor immune responses can be elicited in ACC has fostered interest in checkpoint inhibitors such as anti-PD-1 nivolumab.

3D bioprinting is a powerful enabling technology for the automated fabrication of biomimetic constructs for skin modelling and repair with high resolution and reproducibility. Bioinks, which often comprise the combination of cells and printable biomaterials, are essential for bioprinting 3D cell-laden constructs emulating the architecture, composition and function of native skin. Tissue- and organ-specific decellularized extracellular matrix (dECM) materials are assuming a significant role in bioink design owing their capacity to provide native biophysical and biochemical signals that can elicit distinct cellular responses toward tissue development. Herein, we discuss the rational design of dECM-based bioinks, focusing on processing methods to obtain dECM as well as on bioprinting strategies to engineer 3D constructs for applications in wound healing and in vitroskin modelling.

Several methods for heat exchanger networks (HEN) design are based on the use of superstructures. The models they give rise to can lead to different design options to be explored in HEN synthesis. In this work, a stage-wise superstructure with new features for the optimal placement of heaters and coolers, including the possibility of the use of multiple utilities, is presented. In the model, those units can be placed in different stream split branches in all stages, differing from the usual allocation at stream ends. Such possibilities yield a more complex mathematical model. To solve it, an improved version of a previously presented hybrid meta-heuristic method was used. Three examples from the literature were studied. The use of the superstructure with the additional utility-related options, as well as the enhanced meta-heuristic solution method, led to configurations with lower associated total annual costs than those reported in previous works.

The development of immune-related adverse events (irAEs) has been associated with improved efficacy of immune checkpoint inhibitors in patients with urothelial cancer, melanoma, and non-small cell lung cancer. Whether this association exists in patients with small cell lung cancer (SCLC) is currently unknown.

Mechanisms of resistance to EGFR exon 20 insertion mutation active inhibitors have not been extensively studied in either robust preclinical models or patient-derived rebiopsy specimens. We sought to characterize on-target resistance mutations identified in EGFRexon 20 insertion-mutated lung cancers treated with mobocertinib or poziotinib and evaluate whether these mutations would or would not have cross-resistance to next-generation inhibitors zipalertinib, furmonertinib, and sunvozertinib.

Intensification of the Agulhas Leakage (AL) during glacial terminations has long been proposed as a necessary mechanism for reverting the Atlantic Meridional Overturning Circulation (AMOC) to its interglacial mode. However, lack of records showing the downstream evolution of AL signal and substantial temporal differences between AL intensification and resumption of deep‐water convection have cast doubt on the importance of this mechanism to the AMOC. Here, we analyze a combination of new and previously published data relating to Mg/Ca‐derived temperatures and ice volume‐corrected seawater δ18O records (δ18OIVC‐SW, as a proxy for relative changes in ocean salinity), which demonstrate propagation of AL signal via surface and thermocline waters to the western South Atlantic (Santos Basin) during Termination II and the early Last Interglacial. The saline AL waters were temporally stored in the upper subtropical South Atlantic until they were abruptly released in two stages into the North Atlantic via surface and thermocline waters at ca. 129 and 123 ka BP, respectively. Accounting for age model uncertainties, these two stages are coeval with the resumption of convection in the Labrador and Nordic seas during the Last Interglacial. We propose a mechanism whereby both active AL and a favorable ocean‐atmosphere configuration in the tropical Atlantic were required to allow flux of AL waters into the North Atlantic, where they then contributed to enhancing the AMOC during the Last Interglacial period. Our results provide a framework that connects AL strengthening to the AMOC intensifications that followed glaciations. During the Quaternary period, the Earth's climate fluctuated between glacial and interglacial states. Such climate transitions, known as glacial terminations, were characterized by rapid changes in ice‐volume, atmospheric CO2levels, and global temperatures. Several geochemical and modeling studies have demonstrated that the Atlantic Meridional Overturning Circulation (AMOC) was strongly inhibited during these periods. In general, meltwater discharge due to ice‐sheet retraction at high latitudes of the North Atlantic seems to have weakened deep‐ocean convection and affected northward transport of heat and salt. To return the AMOC to a fully active mode, the impact of that meltwater had to be counterbalanced. Previous investigations suggested that leakage of salty waters from the Indian Ocean into the South Atlantic (Agulhas Leakage, AL) during glacial terminations played a prominent role in reinstating northward heat and salt transport. However, it is not clear how far into the South Atlantic the influence of the AL can be tracked and how, in terms of timing, it is linked to resumption of deep‐water convection. Here, we focus on glacial Termination II to demonstrate AL signal in the western South Atlantic and how it contributed to enhancing the AMOC during the Last Interglacial. Strong Agulhas Leakage during Termination II affected upper ocean salinity of the western South AtlanticThe tropical ocean‐atmosphere configuration induced recirculation of Agulhas waters within the South Atlantic subtropical gyreTwo intervals of strong freshening of the upper Brazil Current suggests northward transmission of dense waters during the Last Interglacial

Osimertinib is approved for advanced EGFR-mutated NSCLC, and identification of on-target mechanisms of resistance (i.e., EGFRC797S) to this third-generation EGFR inhibitor are evolving. Whether durable control of subsequently osimertinib-resistant NSCLC with the EGFR-sensitizing mutation (SM)/C797S is possible with first-generation EGFR inhibitors (such as gefitinib or erlotinib) remains underreported, as does the resultant acquired resistance profile.

•The US FDA has overseen regulation of medical devices since the 1976 Medical Device Amendments.•In 2016, the 21st Century Cures Act established oversight of the FDA for medical software.•There are four main types of medical software as defined by the US FDA.•While there are no specific exceptions for AI, the FDA has begun to clear AI software for clinical use.

Atlantic Meridional Overturning Circulation (AMOC) disruption during the last deglaciation is hypothesized to have caused large subsurface ocean temperature anomalies, but records from key regions are not available to test this hypothesis, and other possible drivers of warming have not been fully considered. Here, we present the first reliable evidence for subsurface warming in the South Atlantic during Heinrich Stadial 1, confirming the link between large‐scale heat redistribution and AMOC. Warming extends across the Bølling‐Allerød despite predicted cooling at this time, thus spanning intervals of both weak and strong AMOC indicating another forcing mechanism that may have been previously overlooked. Transient model simulations and quasi‐conservative water mass tracers suggest that reduced northward upper ocean heat transport was responsible for the early deglacial (Heinrich Stadial 1) accumulation of heat at our shallower (~1,100 m) site. In contrast, the results suggest that warming at our deeper site (~1,900 m) site was dominated by southward advection of North Atlantic middepth heat anomalies. During the Bølling‐Allerød, the demise of ice sheets resulted in oceanographic changes in the North Atlantic that reduced convective heat loss to the atmosphere, causing subsurface warming that overwhelmed the cooling expected from an AMOC reinvigoration. The data and simulations suggest that rising atmospheric CO2did not contribute significantly to deglacial subsurface warming at our sites. Western South Atlantic waters between 1.1 and 1.9 km warmed by ~2.5‐3.0 °C from the LGM to the HoloceneDeglacial subsurface warming continued into the Bølling‐Allerød, after Atlantic Meridional Overturning Circulation had recoveredThe demise of ice sheets likely prevented a return to cooler temperatures during the Bølling‐Allerød

The impact of outdated channel state information on two sequential relay selection schemes for device-to-device underlaid cellular networks over mixed fading channels is investigated. To this end, the mutual outage probability (MOP) is analyzed in which an easy-to-evaluate analytical expression for the MOP is derived. Moreover, an asymptotic analysis of the MOP at high signal-to-noise ratio is provided, and the diversity order is evaluated.