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The large mid-infrared (MIR) spectral region, ranging from 2.5 µm to 25 µm, has remained under-exploited in the electromagnetic spectrum, primarily due to the absence of viable transceiver technologies. Notably, the 8-14 µm long-wave infrared (LWIR) atmospheric transmission window is particularly suitable for free-space optical (FSO) communication, owing to its combination of low atmospheric propagation loss and relatively high resilience to turbulence and other atmospheric disturbances. Here, we demonstrate a direct modulation and direct detection LWIR FSO communication system at 9.1 µm wavelength based on unipolar quantum optoelectronic devices with a unprecedented net bitrate exceeding 55 Gbit s -1 . A directly modulated distributed feedback quantum cascade laser (DFB-QCL) with high modulation efficiency and improved RF-design was used as a transmitter while two high speed detectors utilizing meta-materials to enhance their responsivity are employed as receivers; a quantum cascade detector (QCD) and a quantum-well infrared photodetector (QWIP). We investigate system tradeoffs and constraints, and indicate pathways forward for this technology beyond 100 Gbit s -1 communication., (© 2024. The Author(s).)

This study investigates the potential of long-wave infrared (LWIR) free-space optical (FSO) transmission using multilevel signals to achieve high spectral efficiency. The FSO transmission system includes a directly modulated-quantum cascade laser (DM-QCL) operating at 9.1 µm and a mercury cadmium telluride (MCT) detector. The laser operated at the temperature settings of 15°C and 20°C. The experiment was conducted over a distance of 1 m and in a lab as a controlled environment. We conduct small-signal characterization of the system, including the DM-QCL chip and MCT detector, evaluating the end-to-end response of both components and all associated electrical elements. For large-signal characterization, we employ a range of modulation formats, including non-return-to-zero on-off keying (NRZ-OOK), 4-level pulse amplitude modulation (PAM4), and 6-level PAM (PAM6), with the objective of optimizing both the bit rate and spectral efficiency of the FSO transmission by applying pre- and post-processing equalization. At 15°C, the studied LWIR FSO system achieves net bitrates of 15 Gbps with an NRZ-OOK signal and 16.9 Gbps with PAM4, both below the 6.25% overhead hard decision-forward error correction (6.25%-OH HD-FEC) limit, and 10 Gbps NRZ-OOK below the 2.7% overhead Reed-Solomon RS(528,514) pre-FEC (KR-FEC limit). At 20°C, we obtained net bitrates of 14.1 Gbps with NRZ-OOK, 16.9 Gbps with PAM4, and 16.4 Gbps with PAM6. Furthermore, we evaluate the BER performance as a function of the decision feedback equalization (DFE) tap number to explore the role of equalization in enhancing signal fidelity and reducing errors in FSO transmission. Our findings accentuate the competitive potential of DM-QCL and MCT detector-based FSO transceivers with digital equalization for the next generation of FSO communication systems.

Background: The objective of this study is to conduct a systematic review and meta-analysis examining the relationship between the vasoactive-inotropic score (VIS) and patient outcomes in surgical settings., Methods: Two independent reviewers searched PubMed, Web of Science, EMBASE, Scopus, Cochrane Library, Google Scholar, and CNKI databases from November 2010, when the VIS was first published, to December 2022. Additional studies were identified through hand-searching the reference lists of included studies. Eligible studies were those published in English that evaluated the association between the VIS and short- or long-term patient outcomes in both pediatric and adult surgical patients. Meta-analysis was performed using RevMan Manager version 5.3, and quality assessment followed the Joanna Briggs Institute (JBI) Critical Appraisal Checklists., Results: A total of 58 studies comprising 29,920 patients were included in the systematic review, 34 of which were eligible for meta-analysis. Early postoperative VIS was found to be associated with prolonged mechanical ventilation (OR 5.20, 95% CI 3.78-7.16), mortality (OR 1.08, 95% CI 1.05-1.12), acute kidney injury (AKI) (OR 1.26, 95% CI 1.13-1.41), poor outcomes (OR 1.02, 95% CI 1.01-1.04), and length of stay (LOS) in the ICU (OR 3.50, 95% CI 2.25-5.44). The optimal cutoff value for the VIS as an outcome predictor varied between studies, ranging from 10 to 30., Conclusion: Elevated early postoperative VIS is associated with various adverse outcomes, including acute kidney injury (AKI), mechanical ventilation duration, mortality, poor outcomes, and length of stay (LOS) in the ICU. Monitoring the VIS upon return to the Intensive Care Unit (ICU) could assist medical teams in risk stratification, targeted interventions, and parent counseling., Systematic Review Registration: PROSPERO CRD42022359100., (© 2023. The Author(s).)

Despite the proliferation of research on anesthesiology training at all stages of medical education, there is relatively little published literature surveying the perspectives and concerns of anesthesiologists regarding cardiovascular anesthesia training. Therefore, we conducted a survey to investigate the attitudes, barriers, expectations, stress experiences, satisfaction, and future aspirations of anesthesiologists trained at a tertiary cardiovascular specialty hospital in China. A questionnaire survey was conducted among 260 anesthesiologists who received cardiovascular anesthesia training at departments of anesthesiology in a tertiary cardiovascular specialty hospital in China. After the study protocol was approved, electronic questionnaires were distributed to the target group through the online survey software "Wen Juan Xing." Respondents were asked to complete an anonymous questionnaire on their smartphones through WeChat, with the restriction of one response per device enabled. Of the 260 trainees, 240 (98%) completed the questionnaire. The majority of the trainees were 31 years of age or above. A large majority had approximately 10 years of clinical anesthesia practice, and nearly one-third had never undertaken cardiovascular specialty anesthesia practice before. The most common reasons for attending the refresher training were the need to learn basic specialty theory and improve clinical skills. The barriers were mainly time constraints or staff shortages in the department. Sixty-one (93.8%) trainees described the experience as "stressful or highly stressful" and identified poor teacher interaction as the highest-ranking stressor. Anesthesiologists were most dissatisfied with job rewards, with a satisfaction rate of only 15%. Anesthesiologists are highly stressed during the refresher training. Poor teacher interaction and low job rewards were identified as the highest-ranking stressors during cardiovascular anesthesia training. Training providers need to pay more attention to these stressors to enhance the quality of cardiovascular anesthesia training., Competing Interests: The authors have no funding and conflicts of interest to disclose., (Copyright © 2023 the Author(s). Published by Wolters Kluwer Health, Inc.)

Thoracic endovascular aortic repair (TEVAR) is a new alternative surgical treatment for aortic pathologies, which is more minimally invasive. The aim of current study was to summarize the single-center experience of general anesthesia for patients undergoing TEVAR. In adult patients undergoing surgery for congenital heart disease, the strategy of "fast-track" anesthesia with early extubation in theater is associated with a shorter intensive care unit (ICU) stay, and lower health-care-related costs. Fast-track anesthesia has not been assessed in patients under TEVAR. Adult patients who received general anesthesia for TEVAR in our center from January 2020 to December 2020 were included. Baseline characteristics, airway management, anesthetic techniques and major complications were collected. A total of 204 (171 male, mean age 58.1 ± 11.5 years) patients met inclusion criteria for this study. The distribution of pathologies included 29 descending thoracic aneurysms, 87 type B dissections, and 88 intramural hematoma/perforating aortic ulcer. Etomidate was the induction agent in 190 (93.1%) patients, compared with propofol in 16 (7.8%). Cisatracurium was the muscle relaxant in 201 (98.5%), compared with rocuronium in 3 (1.5%). Midazolam (benzodiazepines) was given to 124 (60.8%) patients during anesthesia induction. General anesthesia was maintained with sevoflurane in 85.3% (174) patients, dexmedetomidine in 201 (98.5%) and propofol in 204 (100%). Postoperative length of stay (LOS) in the hospital was 6.0 (5.0-7.8) days. LOS in the ICU was 23.0 (20.0-27.8) hours. Overall neurologic event rate was 2.0% (n = 4) (spinal cord ischemia 1.5% [n = 3]; stroke 0.5% [n = 1]). After matching, patients who received "fast-track" anesthesia had a shorter LOS in ICUs (21.0 [18.0-24.0] vs 24.0 [20.0-44.0] hours; P = .005), and a shorter postoperative LOS in hospital (5.0 [4.0-7.0] vs 6.0 [5.0-8.0] days; P = .001). There were no in-hospital deaths. Fast-track anesthesia is feasible and safe in patients underwent TEVAR. This management strategy is associated with shorter LOS of ICU and total postoperative hospital stays. An early extubation strategy should be implemented for hemodynamically stable patients., Competing Interests: The authors have no funding and conflicts of interest to disclose., (Copyright © 2023 the Author(s). Published by Wolters Kluwer Health, Inc.)

High bitrate mid-infrared links using simple (NRZ) and multi-level (PAM-4) data coding schemes have been realized in the 8 µm to 14 µm atmospheric transparency window. The free space optics system is composed of unipolar quantum optoelectronic devices, namely a continuous wave quantum cascade laser, an external Stark-effect modulator and a quantum cascade detector, all operating at room-temperature. Pre- and post-processing are implemented to get enhanced bitrates, especially for PAM-4 where inter-symbol interference and noise are particularly detrimental to symbol demodulation. By exploiting these equalization procedures, our system, with a full frequency cutoff of 2 GHz, has reached transmission bitrates of 12 Gbit/s NRZ and 11 Gbit/s PAM-4 fulfilling the 6.25 % overhead hard-decision forward error correction threshold, limited only by the low signal-to-noise ratio of our detector.

Measurements of beam stability for mid-infrared (IR)-emitting quantum cascade lasers (QCLs) are important for applications that require the beam to travel through air to remote targets, such as free-space communication links. We report beam-quality measurement results of narrow-ridge, 4.6 µm-emitting buried-heterostructure (BH) QCLs fabricated using ICP etching and HVPE regrowth. Beam-quality measurements under QCW operation exhibit M 2  < 1.2 up to 1 W for ∼5 µm-wide ridges. 5 µm-wide devices display some small degree of centroid motion with increasing output power (< 0.125 mrad), which corresponds to a targeting error of ∼1.25 cm over a distance of 100 m.

Marine sponges are well known as rich sources of biologically natural products. Growing evidence indicates that sponges harbor a wealth of microorganisms in their bodies, which are likely to be the true producers of bioactive secondary metabolites. In order to promote the study of natural product chemistry and explore the relationship between microorganisms and their sponge hosts, in this review, we give a comprehensive overview of the structures, sources, and activities of the 774 new marine natural products from sponge-derived microorganisms described over the last two decades from 1998 to 2017.

Room temperature surface emission is realized on a large area (1.5 mm × 1.5 mm) photonic crystal quantum cascade laser (PhC-QCL) driven under pulsed mode, at the wavelength around 8.75 μm. By introducing in-plane asymmetry to the pillar shape and optimizing the current injection with a grid-like window contact, the maximum peak power of the PhC-QCL is up to 5 W. The surface emitting beam has a crossing shape with 10° divergence.

Three new sesquiterpenoids (sinuketal ( 1 ), sinulins A and B ( 2 and 3 )) and two new cembranoids (sinulins C and D ( 4 and 5 )), as well as eight known sesquiterpenoids ( 6&ndash;13 ) and eight known cembranoids ( 14&ndash;21 ), were isolated from the Xisha soft coral Sinularia sp. Their structures were elucidated by extensive spectroscopic analysis. Compound 1 possesses an unprecedented isopropyl-branched bicyclo [6.3.0] undecane carbon skeleton with unique endoperoxide moiety, and a plausible biosynthetic pathway of it was postulated. According to the reported biological properties of endoperoxide, the antimalarial, cytotoxic, antiviral, and target inhibitory activities of 1 were tested. Compound 1 showed mild in vitro antimalarial activity against Plasmodium falciparum 3D7, weak cytotoxic activities toward Jurkat, MDA-MB-231, and U2OS cell lines, inhibitory effects against influenza A viruses H1N1 and PR8, as well as mild target inhibitory activity against acetylcholinesterase. The other compounds were evaluated for cytotoxicities against HeLa, HCT-116, and A549 tumor cell lines and target inhibitory activities against protein tyrosine phosphatase 1B (PTP1B). Compound 20 exhibited cytotoxicities against HeLa and HCT-116, and compounds 5 , 11 , and 15 showed mild target inhibitory activities against PTP1B.

Two pairs of new non-brominated racematic pyrrole derivatives, (±)-nakamurine D (1) and (±)-nakamurine E (2), two new diterpene alkaloids, isoagelasine C (16) and isoagelasidine B (21), together with 13 known pyrrole derivatives ((±)-3 - 15), five known diterpene alkaloids (17 - 20, 22) were isolated from the South China Sea sponge Agelas nakamurai. The racemic mixtures, compounds 1 - 4, were resolved into four pairs of enantiomers, (+)-1 and (-)-1, (+)-2 and (-)-2, (+)-3 and (-)-3, and (+)-4 and (-)-4, by chiral HPLC. The structures and absolute configurations were elucidated on the basis of comprehensive spectroscopic analyses, quantum chemical calculations, quantitative measurements of molar rotations, application of van't Hoff's principle of optical superposition, and comparison with the literature data. The NMR and MS data of compound 3 are reported for the first time, as the structure was listed in SciFinder Scholar with no associated reference. These non-brominated pyrrole derivatives were found in this species for the first time. Compound 18 showed valuable cytotoxicities against HL-60, K562, and HCT-116 cell lines with IC 50 values of 12.4, 16.0, and 19.8 μm, respectively. Compounds 16 - 19, 21, and 22 showed potent antifungal activities against Candida albicans with MIC values ranging from 0.59 to 4.69 μg/ml. Compounds 16 - 19 exhibited moderate antibacterial activities against Proteusbacillus vulgaris (MIC values ranging from 9.38 to 18.75 μg/ml)., (© 2017 Wiley-VHCA AG, Zurich, Switzerland.)

The formation of coacervates between soybean protein isolate (SPI) and chitosan was investigated by turbidimetric analysis and coacervate yield determination as a function of pH, temperature, time, ionic strength, total biopolymer concentration (TB(conc)) and protein to polysaccharide ratio (R(SPI/Chitosan)). The interaction between SPI and chitosan yielded a sponge-like coacervate phase and the optimum conditions for their coacervation were pH 6.0-6.5, a temperature of 25 °C, and a R(SPI/Chitosan) ratio of four independently of TB(conc). NaCl inhibited the complexation between the two biopolymers. Fourier transform infrared spectroscopy (FTIR) revealed that the coacervates were formed through the electrostatic interaction between the carboxyl groups of SPI (-COO(-)) and the amine groups of chitosan (-NH(3)(+)), however hydrogen bonding was also involved in the coacervation. Differential scanning calorimetry (DSC) thermograms indicated raised denaturation temperature and network thermal stability of SPI in the coacervates due to SPI-chitosan interactions. Scanning electron microscopy (SEM) micrographs revealed that the coacervates had a porous network structure interspaced by heterogeneously sized vacuoles., (Copyright © 2012 Elsevier Ltd. All rights reserved.)