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Thermoelectric technology has been widely used for key areas, including waste-heat recovery and solid-state cooling. We discovered tin selenide (SnSe) crystals with potential power generation and Peltier cooling performance. The extensive off-stoichiometric defects have a larger impact on the transport properties of SnSe, which motivated us to develop a lattice plainification strategy for defects engineering. We demonstrated that Cu can fill Sn vacancies to weaken defects scattering and boost carrier mobility, facilitating a power factor exceeding ~100 microwatts per centimeter per square kelvin and a dimensionless figure of merit ( ZT ) of ~1.5 at 300 kelvin, with an average ZT of ~2.2 at 300 to 773 kelvin. We further realized a single-leg efficiency of ~12.2% under a temperature difference (Δ T ) of ~300 kelvin and a seven-pair Peltier cooling Δ T max of ~61.2 kelvin at ambient temperature. Our observations are important for practical applications of SnSe crystals in power generation as well as electronic cooling.

Thermoelectric materials allow for direct conversion between heat and electricity, offering the potential for power generation. The average dimensionless figure of merit ZT ave determines device efficiency. N-type tin selenide crystals exhibit outstanding three-dimensional charge and two-dimensional phonon transport along the out-of-plane direction, contributing to a high maximum figure of merit Z max of ~3.6 × 10 −3 per kelvin but a moderate ZT ave of ~1.1. We found an attractive high Z max of ~4.1 × 10 −3 per kelvin at 748 kelvin and a ZT ave of ~1.7 at 300 to 773 kelvin in chlorine-doped and lead-alloyed tin selenide crystals by phonon-electron decoupling. The chlorine-induced low deformation potential improved the carrier mobility. The lead-induced mass and strain fluctuations reduced the lattice thermal conductivity. Phonon-electron decoupling plays a critical role to achieve high-performance thermoelectrics.

Thermoelectric materials transfer heat and electrical energy, being useful for power generation or cooling applications. Many of these materials have narrow bandgaps, especially for cooling applications where this property has been seen as particularly important for enhancing the thermoelectric properties. We developed SnSe crystals with a wide bandgap Eg ~ 33 kBT with attractive thermoelectric properties through Pb alloying. The momentum and energy multiband alignment promoted by Pb alloying resulted in an ultra-high power factor ~75 μWcm–1K–2 at 300 K, and a ZTave ~ 1.90. We show that a 31-pair thermoelectric device can produce a power generation efficiency ~4.4% and a cooling ΔTmax ~ 45.7 K. These results demonstrate that wide bandgap compounds can be used for thermoelectric cooling applications.

Due to the intrinsically plentiful Sn vacancies, developing n-type SnTe thermoelectric materials is a big challenge. Herein, n-type SnTe thermoelectric materials with remarkable performance were successfully synthesized through suppressing Sn vacancies, followed by electron-doping. Pb alloying notably depressed the Sn vacancies via populating Sn vacancies in SnTe (supported by transmission electron microscopy), and the electrical transports were shifted from p-type to n-type through introducing electrons using I doping. In the n-type SnTe, we found that the electrical conductivity could be enhanced by increased carrier mobility through sharpening conduction bands after alloying Pb, while the lattice thermal conductivity could be reduced via strong phonon scattering after introducing defects by Pb alloying and I doping. Resulting from these enhancements, the n-type Sn0.6Pb0.4Te0.98I0.02 achieves a notably high ZTmax ∼ 0.8 at 573 K and a remarkable ZTave ∼ 0.51 at 300-823 K, which can match many excellent p-type SnTe. This work indicates that n-type SnTe could be experimentally acquired and is a promising candidate for thermoelectric generation, which will stimulate further research on n-type SnTe thermoelectric materials and even devices on the basis of both n- and p-type SnTe legs.

In this work we investigated the thermoelectric transport behaviors of p-type PbS and n-type PbS with an emphasis on its contrasting electronic band structures. We found that the Seebeck coefficients of p-type PbS increased faster with rising temperature than that of n-type PbS with the same carrier concentration. The Density functional theory (DFT) calculation of the energy band structure of PbS as a function of temperature illustrates a significant contribution from multiple valence bands in K-doped p-type PbS. This work revealed one important information that manipulating electronic bands is also suitable in developing high-performance PbS thermoelectric systems.

The following trends emerged in international critical care practice in 2019: increasing analysis to phenotypes of sepsis and acute respiratory distress syndrome (ARDS), increasing evidences of early initiating of vasopressors and antibiotics for septic shock, also including the early furosemide stress test for critically ill patients with acute kidney injury (AKI). In addition, there are many significantly important trials with positive results: high dose vitamin C for septic shock, weaning strategy with pressure support ventilation (PSV) mode, tranexamic acid for patients with acute traumatic brain injury, and new monoclonal antibody for Ebola virus disease. And there are also negatives trials as following: individual mechanical ventilation, maximal recruitment open lung ventilation or early neuromuscular blockade for moderate-to-severe ARDS, N95 respirators preventing influenza, flexible family visit program against delirium or early sedation with dexmedetomidine to mechanically ventilated patients, intensive care unit (ICU) diary or nurse-led preventive psychological intervention against posttraumatic stress disorder (PTSD) in patients with mechanical ventilation, recombinant human soluble thrombomodulin (rhsTM) in patients with sepsis-associated coagulopathy, and so on. Further investigations should be focus on the phenotype analysis, by which individualized management fitting for specific pathophysiologic and immune characters for each patient could be clarified.

Background Re-capture of the differences between tumor and normal tissues observed at the patient level in cell cultures and animal models is critical for applications of these cancer-related differences. The epithelial-mesenchymal transition (EMT) process is essential for tumor migratory and invasive capabilities. Although plenty of EMT markers are revealed, molecular features during the early stages of EMT are poorly understood. Methods A cell-based model to induce lung cell (A549) EMT using conditioned medium of in vitro cancer activated fibroblast (WI38) was established. High-throughput sequencing methods, including RNA-seq and miRNA-seq, and advanced bioinformatics methods were used to explore the transcriptome profile transitions accompanying the progression of EMT. We validated our findings with experimental techniques including transwell and immunofluorescence assay, as well as the TCGA data. Results We have constructed an in vitro cell model to mimic the EMT in patients. We discovered that several new transcription factors were among the early genes (3 h) to respond to cancer micro-environmental cues which could play critical roles in triggering further EMT signals. The early EMT markers also included genes encoding membrane transporters and blood coagulation function. Three of the nine-examined early EMT hallmark genes, GALNT6, SPARC and HES7, were up-regulated specifically in the early stages of lung adenocarcinoma (LUAD) and confirmed by TCGA patient transcriptome data. In addition, we showed that miR-3613, a regulator of EGFR pathway genes, was constantly repressed during EMT progress and indicative of an epithelial miRNA marker. Conclusions The CAF-stimulated EMT cell model may recapture some of the molecular changes during EMT progression in clinical patients. The identified early EMT hallmark genes GALNT6, SPARC and HES7and miR-3613 provide new markers and therapeutic targets for LUAD for the further clinical diagnosis and drug screening. Electronic supplementary material The online version of this article (10.1186/s12885-019-5885-9) contains supplementary material, which is available to authorized users.

In 2018, a bunch of considerable positive progresses have been presented, including a revised "hour-1 bundle" introduced by international guideline for management of sepsis and septic shock, trans-pulmonary pressure monitoring via esophageal manometry in acute respiratory distress syndrome (ARDS) models, successful trials for new antibiotics, angiotensin II in patients with vasodilatory shock and renal replacement therapy, advanced airway management in out-of-hospital cardiac arrest (OHCA) patients as well cellular immunotherapy for septic shock. But some of investigational trials did not yield expected results. For example, extracorporeal membrane oxygenation (ECMO) therapy for ARDS patients, the strategy of sequencing weaning with early extubation to noninvasive ventilation, prevention of delirium with haloperidol, surrogate decision supported by interprofessional intensive care unit (ICU) team and prophylaxis for gastrointestinal stress ulceration with pantoprazole in ICU. And more importantly, it has been obvious that the voices and evidences gathered by the opponents against guidelines development, compulsory polices of implementing bundled strategy, market position of hydroxyethyl-starch solutions (HES) and the usage of steroid in septic shock have been largely strengthen, highlighting a more divided and controversial situation.

Figure S3. Expression and functionprofile of eigengenemodules. (A) Expression pattern of genes represented in brown and green modules. (B)GO biological processes enriched with genesbelonging to brown and greenmodules. (PDF 928 kb)

Figure S2. Temporal gene expression changes of CAF induced A549 EMT. Venn diagrams of DEGs at 3, 6, 12 and 24â h. Numbers of down-regulated (A) and up-regulated (B) genes at each time point were shown. (PDF 2195 kb)

Figure S1. Temporal mRNA expression changes of CAF induced A549 EMT. (A-G) Bar plots show expression levels of EMT marker genes in A549 cells with CAF conditioned medium or control treatment. *, 0.01

Figure S5. Proposed model figure of the main methods and findings in this study. Early EMT markers including GALNT6, SPARC and HES7 showed elevated expression level at early stages of CAF-CM induction. Downregulation of miR-3613 may also promotes EMT by releasing the EGFR signaling pathway genes. (PDF 189 kb)

Figure S4. Temporal miRNA expression changes of CAF induced A549 EMT. Venn diagrams of DEmiRNAs at 3, 6, 12 and 24â h. Numbers of down-regulated (A) and up-regulated (B) miRNAs at each time point were shown. (C) Bar plot showing the RT-qPCR results of miR-3613 mimic experiments in A549 cells. (PDF 2329 kb)

PbS has attracted much attention as an excellent thermoelectric material with high development space at middle temperature scope. The thermoelectric performance for n-type PbS was boosted by the cooperative effects of resonance level and Cu dynamic doping in our research. In the first place, In doping improved the electrical transport performance of n-type PbS effectively on account of optimal carrier concentration and resonant level effects, and reduced the lattice thermal conductivity by reason of heightened phonon scattering through impurity atoms scattering simultaneously. Secondly, Cu dynamic doping further increased average power factor to ~18.8 μW cm−1 K−2 at 423 K- 823 K of Pb0.995In0.005S+3%Cu owing to higher Seebeck coefficients and suppressed electronic thermal transports at vast temperature span. In result, the best thermoelectric figure of merit (ZT) of Pb0.995In0.005S+3%Cu at 723 K reached ~1.1 and a record large average ZT (ZTave) of Pb0.995In0.005S+3%Cu was achieved ~ 0.8 at 423 K-823 K, which is vital in the implementation of thermoelectric technology.

In this work, the thermoelectric performance of p-type PbS was boosted remarkably through Na doping and introducing Cu2S. Firstly, the electrical transport properties (power factor) of p-type PbS was optimized via Na doping, and the maximum ZT ∼ 0.67 was achieved in Pb0.98Na0.02S. Secondly, the total thermal conductivity of Pb0.98Na0.02S was suppressed through introducing Cu2S by means of significantly reducing the electronic thermal conductivity by 80% at 823 K through Cu counter-doping, meanwhile, the power factor of Pb0.98Na0.02S was further enhanced through optimizing carrier concentrations via introducing Cu. The combination of decreasing total thermal conductivities and the optimizing power factors leads to peak ZT ∼1.2 at 823 K in p-type Pb0.98Na0.02S–2%Cu2S. Present results illustrate that introducing Cu2S is an effective method to enhance the thermoelectric performance of p-type PbS through decreasing the electronic thermal conductivity which also has great potential in other thermoelectric materials system.

This paper deals with the problem of robust H ∞ guaranteed cost control for a class of uncertain linear stochastic partial differential systems (SPDSs) with time-varying delay. A state feedback robust H ∞ guaranteed cost controllers are presented based on Lyapunov-Krasovskii functional approach. The designed controllers ensure that the closed-loop systems are robustly stochastically exponentially stable in the mean-square sense with a prescribed H ∞ disturbance attenuation level 7. Sufficient conditions for the existences of desired controllers are established and the derived condition take the form computation tractable linear matrix inequalities (LMIs) although conservation. A numerical example is given to illustrate the effectiveness of the proposed method.

Macroporous and modified macroporous poly(styrene-co-methyl methacrylate-co-divinylbenzene) particles (m-PS and mm-PS) supported Cp2ZrCl2 were prepared and applied to ethylene polymerization using methylaluminoxane (MAO) as cocatalyst. The influences of the swelling response of the support particles on the catalyst loading capabilities of the supports as well as on the activities of the supported catalysts were studied. It was shown that the Zr loadings of the supports and the activities of the supported catalysts increased with the swelling extent of the support particles. The m-PS or mm-PS supported catalysts exhibited very high activities when the support particles were well swollen, whereas those catalysts devoid of swelling treatment gave much lower activities. Investigation on the distribution of the supports in the polyethylene by TEM indicated that the swelling of the support particles allowed the fragmentation of the catalyst particles. In contrast, the fragmentation of the support particles with poor swelling was hindered during ethylene polymerization.

A catalyst with porous polystyrene beads supported Cp2ZrCl2 was prepared and tested for ethylene polymerization with methylaluminoxane as a cocatalyst. By comparison, the porous supported catalyst maintained higher activity and produced polyethylene with better morphology than its corresponding solid supported catalyst. The differences between activities of the catalysts and morphologies of the products were reasonably explained by the fragmentation processes of support as frequently observed with the inorganic supported Ziegler-Natta catalysts. Investigation into the distribution of polystyrene in the polyethylene revealed the fact that the porous polystyrene supported catalyst had undergone fragmentation during polymerization.

Excess intercalation of cationic surfactants into Na-montmorillonites (MMTs) was investigated in organically modified silicates (OMSs), synthesized with MMTs and octadecylammonium chloride (OAC) by systematically varying the surfactant loading level from 0.625 to 1, 1.25, 1.56, 2, and 2.5 with respect to the cation exchange capacity (CEC) of MMTs. Wide-angle X-ray diffraction and thermogravimetric analysis results indicated that the continuous increase of interlayer distances came from the entering of surfactants into the interlayer of MMTs. Excess surfactants were extracted with a Soxhlet apparatus, which showed two kinds of intercalation states of surfactants in the interlayer when the surfactant loading level was beyond the CEC. Fourier transform infrared spectroscopy and differential scanning calorimetry were used to explore the microstructures of OMSs. It was found that the surfactants arranged more orderly as the loading level increased and the excess surfactants piled up in the interlayer together with counterions, forming a sandwiched surfactant layer. On the basis of the results, the layer structures of OMSs and the mechanism by which the surfactants entered the interlayer were expounded: surfactant cations entered the interlayer through cation exchange reactions and were tightly attracted to the silicate platelet surfaces when the surfactant loading level was below the CEC

To investigate the efficacy and related factors of nasal surgery combined with upper air way radiofrequency ablation(RFA) for treatment of obstructive sleep apnea hypopnea syndrome (OSAHS) with chronic nasal blockage.One hundred and three mild or moderate OSAHS patients with chronic nasal blockage were recruited, all cases had nasal surgery and upper airway RFA. All patients were evaluated by body mass index (BMI), Epworth sleep scale (ESS), snoring scale, and nocturnal polysomnography (PSG). Eighty-nine patients were reevaluated at least 6 months after surgery with the preoperative methods.After operation, the apnea and hypopnea index (AHI) decreased from (18.67 +/- 9.48)/h to (9.22 +/- 7.18)/h; the lowest artery oxygen saturation (LSaO2) increased from (0.83 +/- 0.08) to (0.92 +/- 0.06); the Epworth sleep scale(ESS) decreased from (8.74 +/- 5.67) to (5.12 +/- 3.74); the snoring scale decreased from (7.16 +/- 2.85) to (3.56 +/- 2.26), the percentage of time with oxyhemoglobin saturation below 0.90 (CT90) decreased from (18.64 +/- 12.98) to (10.73 +/- 8.29). All of the differences were obvious (P0.01). Success was defined as a postoperative apnea-hypopnea in dex10 events per hour and at least 50% less than the preoperative value. The surgical success rate was 75.3% (67/89). No major perioperative complications occurred.Our findings suggest that nasal surgery combined with upper airway RFA can improve snoring and disease-specific quality of life in patients with anatomic na sal obstruction with mild or moderate OSAHS.

A series of organically modified clays (OMCs) with a surfactant loading range from 0.625 to 2.5 times the cation exchange capacity (CEC) were melt-mixed with maleated polypropylene (PPMA). Wide-angle X-ray diffraction and transmission electron microscopy results of these nanocomposites show that dispersion of clays becomes unfavorable in the PPMA matrix during melt intercalation as the surfactant loading increases in the process of modifying clays, though larger interlayer distances are obtained in their corresponding OMCs. It is even important that clays uniformly disperse at the nanoscale level in the PPMA matrix when the surfactant loadings are below the CEC, which implies that incomplete exchange of inorganic cations in the process of modifying clay benefits the dispersion of clays in the PPMA matrix.

To investigate the efficacy and related factors of Z-palatoplasty for treating severe obstructive sleep apnea hypopnea syndrome (OSAHS).Thirty-two severe OSAHS patients with Friedman II and III oropharyngeal airway had Z-palatoplasty. Twenty-three patients with modified Mallampti Index (MMI) III-IV had coblation tongue channeling (CTC) simultaneously. The patients were followed up for one year post operatively.After operation, the apnea and hypopnea index (AHI) decreased from (54.74 +/- 20.38)/h to (22.72 +/- 18.36)/h; the lowest artery oxygen saturation (LSaO2 ) increased from (0.74 +/- 0.08) to (0.85 +/- 0.14); the Epworth sleep scale (ESS) decreased from (12.24 +/- 5.78) to (5.35 +/- 3.62); the percentage of time with oxyhemoglobin saturation below 0.90 (CT90) decreased from (31.48 +/- 20.15) to (15.73 +/- 12.29). All of the differences were statistically significant (P0.01). According to related criterion of chinese journal of otorhinolaryngology head and neck surgery in 2009, accumulative excellence rate was 71.9% and accumulative valid rate 84.4%. Six patients had temporary velopharyngeal insufficiency and returned to normal after 3 months.Z-palatoplasty is an effective and safe surgical approach for OSAHS patients with Friedman II/III.

Polyethylene-polystyrene blends were synthesized by in situ ethylene polymerization with polystyrene porous beads supported metallocene; the influence of fragmenting support beads on the morphology and the mechanical performance of the blends was investigated.