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In order to solve the problem of sub-synchronous oscillation (SSO) of wind power grid-connected system with modular multilevel converter based on high voltage direct current transmission (MMC-HVDC), which is characterized by frequency drift due to the fluctuation of wind power output and the dynamic interaction of MMC. By considering the coupling characteristics of wind power volatility and the internal harmonic dynamics of MMC, we establish a small-signal model of the interconnection system between the equivalent wind farm and MMC-HVDC, study the dominant factors triggering the system oscillation, and use model predictive control (MPC). The results show that the wind farm output, wind farm terminal voltage and terminal current are the dominant factors leading to SSO frequency drift. It is also verified that the MPC-SSDC control not only effectively suppresses SSOs with single frequency drift, but is also effective when multiple SSOs with different frequencies exist simultaneously. It is shown that MPC-SSDC can self-adapt to the multi-oscillation scenario of wind power grid-connected system to provide frequency and damping support for the system.

A contact angle observed for a liquid–solid system is not necessarily a unique value, and a few contact angles need to be considered carefully in relation to liquid spreading, adhesion and phase separation. Understanding of the significance of different contact angles has improved in the last few years through direct measurements of interactive forces between droplets/bubbles and solids together with the simultaneous visualization of the changes in their shapes. A microelectronic balance system is employed to measure the force of spreading after either liquid droplet or gas bubble attachment to a substrate surface and the droplet/bubble–substrate adhesion forces after droplet/bubble compression, retraction and detachment. Equipped with a camera in flank and data-acquisition software, the instrument measures directly the forces, monitors droplet/bubble–surface separation with respect to distances over which the droplet/bubble stretches and collects optical images simultaneously. The images are used to analyze capillary pressure and surface tension forces based on the measured droplet/bubble dimensions, shapes of surfaces and values of contact angles. These measurements allow researchers to correlate the advancing, receding and most stable contact angles with liquid–solid interactive forces and analyze their scientific meaning. This review summarizes the very recent literature reports on measurements and interpretation of liquid droplet/gas bubble interactive forces and associated contact angles.

Droplet depinning on superhydrophobic surfaces is pervasive in nature and critical to many applications and hence has been studied extensively over the past few decades. A consensus has been reached that the droplet depinning force mainly stems from the synergistic dynamics of the three-phase contact line and the liquid–vapor interface. Nevertheless, the aforementioned conclusions were made using simple (pure water) droplets depinning on rigid superhydrophobic surfaces, denoted as simple rigid wetting, where the main influencing factors are liquid–vapor interfacial tension, surface texture geometry and material wettability. In recent years, an increasing amount of attention has been paid to complex soft wetting, where liquid physiochemical properties (e.g. viscoelasticity) and solid surface rigidity play an important role. To encourage the investigation of complex soft wetting, in this perspective, depinning of simple droplets on soft surfaces and depinning of viscoelastic droplets on rigid surfaces are briefly introduced. Then, possible factors that affect viscoelastic droplet depinning on soft superhydrophobic surfaces are discussed. Moreover, applications that are highly relevant to complex soft wetting are introduced.

IntroductionStudies investigating surgery for second primary non-small cell lung cancer (SP) patients are rare. The aim of this study was to explore the effects of surgical methods and regional lymph node (LN) dissection on lung cancer-specific mortality (LCSM) in stage I SP patients following surgery for stage I first primary non-small cell lung cancer (FP).MethodsData on patients diagnosed with stage I SP after surgery for stage I FP were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. Cumulative incidence function (CIF) curves, a competing risk model and propensity score matching (PSM) were adopted to compare the LCSM among different subgroups (including surgery and regional LN dissection).ResultsA total of 238 stage I SP patients were extracted from the SEER database. Overall, the 5-year LCSM rate was 29.8% (CI: 23.1%-36.5%) for the whole cohort. Both before and after PSM, lobectomy had a similar LCSM incidence as sublobectomy, and ≥4 regional LN dissections had a significantly lower LCSM incidence than 1~3 regional LN dissections.In addition, patients who underwent 1~3 regional LN dissections had a comparable incidence of LCSM to those without LN dissections.DiscussionStage I SP patients tended to gain more survival benefits when surgeons dissect ≥4 regional LNs. Allowing for the comparable LCSM incidence of sublobectomy to lobectomy, sublobectomy may be a reasonable choice for thoracic surgeons when performing surgery for these patients.

Adhesion of a liquid droplet to a solid surface is a result of solid surface interactions with surrounding fluids, affected by its wettability and morphology. Unfortunately, the direct measurements of adhesion forces are rarely reported in the scientific literature, especially for solids with curvatures. In this study, by using a high-sensitivity microelectronic mechanical balance which vertically deposits and then pulls liquid droplets, the spreading and adhesion forces for water and ethylene glycol droplets on spherical surfaces of polyethylene terephthalate (PET) with radii of curvature from 2 to 8 mm were recorded. Results show that the surface curvature does not affect the advancing and most-stable contact angles but affects the extent of spreading and maximum adhesion forces. The solid surface curvature affects both surface tension and Laplace pressure forces at the spreading point, whereas it mainly affects the Laplace pressure force at the maximum adhesion point.

Background Neoadjuvant therapy followed by esophagectomy has been recognized as an effective treatment for locally advanced esophageal cancer, though still has a dismal prognosis. Antibodies against programmed death 1 (PD-1) protein improve survival in patients with advanced or metastatic esophageal squamous cell carcinoma (ESCC) compared with chemotherapy in second-line therapy. However, neoadjuvant PD-1 inhibitor combined with chemotherapy has not been tested in locally advanced ESCC. We conducted this study to evaluate the efficacy and safety of pd-1 inhibitor in neoadjuvant chemotherapy. Methods In this study, we administered 28 adults with untreated, surgically resectable locally advanced ESCC. PD-1 inhibitor with chemotherapy [albumin paclitaxel 100 mg/m2 on days 1 and 8 + carboplatin with an area under the curve (AUC) of 5 on day 1] were administered every 3 weeks intravenously, and surgery was performed approximately 3-5 weeks after the second dose. The primary purpose of the study was to evaluate the feasibility and safety of this regimen. Results In all, 28 locally advanced ESCC patients were enrolled, 27 patients received surgery, 9 (33.3%) patients' postoperative pathological specimens suggested pCR, and 11 (40.7%) patients' primary tumor suggested complete response. Neoadjuvant PD-1 inhibitor with chemotherapy had an acceptable side-effect profile, 26 patients' tumors were completely resected (96.3% were R0). According to the RESIST v.1.1, the response in all 27 patients was evaluated by a computed tomography (CT) scan before surgery, showing 12 patients with complete response (CR), 12 with partial response (PR), and 3 with stable disease (SD). For surgical procedures, 15 (55.6%) patients underwent minimal invasive surgery, 4 (14.8%) underwent right transthoracic open esophagectomy, and 8 (29.6%) underwent hybrid approaches. Conclusions The novel treatment of PD-1 inhibitor with chemotherapy in the neoadjuvant setting for locally advanced ESCC produced satisfactory outcomes: an unprecedentedly high pCR rate for neoadjuvant chemotherapy, a high R0 resection rate, and a low-toxicity profile were achieved. The long-term efficiency of this novel treatment and the validity of the present findings should be confirmed with longer follow-up and prospective comparative trials.

To detect the internal humidity of the transformer accurately and sensitively and eliminate the interference caused by electromagnetic fields, an interferometric measurement is proposed in this paper for the first time, to the best of our knowledge. The phase value distribution of the interferogram affected by humidity can be extracted quantitatively. The peak-to-peak value (P-P) of the phase image can reflect the humidity, according to theoretical analysis, and the main factors affecting the P-P are current and humidity. It has been tested by currents of 800 A, 1000 A, and 1200 A and different humidities. The paper reveals the relationship between humidity and P-P, proving that it is a reasonable application of real-time measurement of internal humidity in the transformer.

This article investigates the maximum spreading of ferrofluid droplets impacting on a hydrophobic surface under nonuniform magnetic fields. A generalized model for scaling the maximum spreading is developed. It is observed that, if the magnetic field strength is zero, a ferrofluid droplet not only demonstrates similar spreading dynamics as the water droplet but also obeys the same scaling law for the maximum spreading factor. Therefore, this article emphasizes the effects of magnetic field strength. In this regard, a dimensionless parameter (

Background and Objective Tumor microenvironment is a complex and dynamic community, which plays a crucial role in tumor progression via the co-evolution of cancer cells and tumor stroma. Among them, tumor-associated macrophages (TAMs) and tumor neo-vessels are two key components in the tumor microenvironment during cancer invasion. In addition, programmed cell death ligand 1/programmed cell death ligand 1 (PD-1/PD-L1) also plays an important role in tumorigenesis and development, and the clinical strategies to block PD-1/PD-L1 pathway could have great benefits for cancer patients. This study was aimed at analyzing the quantitative expression and prognostic significance of TAMs, tumor neo-vessels and PD-L1 in tumor microenvironment and exploring the relations between the expression of above components with the patients’ prognosis of non-small cell lung cancer (NSCLC). Methods Clinico-pathological data and surgical specimens of 92 patients with NSCLC were collected, and immunohistochemistry was used to stain the expression of TAMs, tumor neo-vessels and PD-L1 on tumor tissue and peri-tumor tissues. The inverted microscopy was used to take pictures and Image-pro Plus 6.0 software was used for quantitative analysis. The clinicopathological characteristics and overall survival (OS) were analyzed. Results The median OS of 92 NSCLC cases was 22.5 month. The expression of TAMs, tumor neo-vessels and PD-L1 in tumor tissue and peri-tumor tissues were not statistically significant (P>0.05). According to the cutoff of above key three components in tumor microenvironment, all the cases could be classified into high, middle and low expression groups. The survival analysis demonstrated that the OS in high expression group of TAMs (P=0.016) and PD-L1 (P=0.002) was shorter than the other two groups, respectively, with statistical significance. The OS in high tumor neo vessels group was shorter than the other two groups. However, there was no statistical significance between these three group (P=0.626). Combined with above the three components, all the cases could be classified into low, middle and high density groups. The survival analysis demonstrated that the median OS of combined high density group was shorter than the other two groups (P=0.001). Multivariate analysis by Cox regression indicated that pathological type, TAMs and PD-L1 expression were the independent prognostic factors. Conclusion The key components of TAMs and PD-L1 in tumor microenvironment are closely related to the prognosis of NSCLC patients.

Arsenic trioxide (ATO) is widely studied for its antitumor efficacy and several recent studies suggested the immune modulatory effects of ATO in animal models. In this study we found ATO treatment induced increased ROS production and DNA damage in esophageal squamous cell carcinoma (ESCC) cells, led to DNA damage mediated degradation of Cyclin D1 and upregulation of PD-L1 in these cancer cells. Mechanistically, we found ATO induced a transient upregulation and nuclear translocation of Cyclin D1 by sumoylation. Followed with increased ubiquitination and degradation of Cyclin D1 through T286 phosphorylation, and at least partly mediated by Stat1 Y701 phosphorylation. We observed inversed correlations between Cyclin D1 and PD-L1 expression levels in human ESCC tissues. With 4NQO induced PD-L1 humanized mouse oral and esophageal squamous carcinoma model, we found combinatory administration of ATO and check point inhibitor resulted in a significant reduction of tumor volumes. Inversed correlation between Cyclin D1 with PD-L1 was also observed in the 4NQO induced mouse ESCC and OSCC model. Together, these data suggested ATO induced degradation of Cyclin D1 and functional suppression of CDK4/6 pathway sensitized OSCC and ESCC to checkpoint inhibitor treatment.

Background Airway-gastric fistulas (AGFs) are rare but life-threatening complications after esophagectomy for esophageal cancer. Their effective and reasonable management is challenging and still controversial. This study reports the classification and management strategies of post-esophagectomy AGF based on a retrospective analysis of 26 cases in two large volume centers in China. Methods Between January 2000 and December 2017, 6,316 consecutive patients with esophageal carcinoma underwent esophagectomy. AGF was verified in 26 patients. The patients with AGF were divided into two types based on the anatomic characteristics of the fistula. Type I was characterized by the presence of fistula orifices in digestive tract that were higher than those in the airway and were treated with conservative management. Type II had both fistula orifices located on the same horizontal plane and were treated with surgical management. Pearson Chi-Square (R software) was used to compare mortality rates. Results From January 2000 and December 2017, 26 cases occurred AGF in 6,316 consecutive patients with esophageal carcinoma underwent esophagectomy and the incidence of AGF was 0.4%. Ten of 12 patients with type I AGF survived. Nine of 14 patients with type II AGF died. There was a significantly difference in the mortality rates between patients with AGF type I and II, which was 16.7% (2/12) and 64.3% (9/14) (χ2=6.003, P=0.014), respectively. Conclusions AGF may be classified into two types according to the anatomic characteristics. Type I patients may be cured by conservative management and type II patients, require surgical intervention with pedicled tissues flap wrapping of the airway.

Aiming at the problems of large leakage current and low efficiency of existing transformerless single-phase grid-connected photovoltaic inverters, a novel transformerless single-phase grid-connecte...

Droplet transport on a cylindrical wire has applications in numerous fields such as fog collection, mist elimination, filtration, and oil/water separation. This work reports a droplet transport phenomenon on a superhydrophilic wire that shows a transient velocity powered not by the gradient of substrate geometry or wettability but primarily by the surface-to-kinetic energy transition that occurs along the axial direction upon coalescence. The transition efficiency is mainly limited by the viscous friction at the local liquid wedge, a relationship that a modified Ohnesorge number can capture.

With the rapid growth of urban power transmission cable scale, the harmonic pollution in the high-voltage power grid is more transmitted to other power grids of different voltage levels, which makes the harmonic transmission more complicated, increases the harmonic emission level, and makes it difficult to quantitatively analyze and study the allowable value of users’ electrical pollution emission. Therefore, in this paper, by establishing the harmonic conduction model of the urban high-voltage power grid and considering the equivalent circuit of transformer and transmission cable in the urban power grid, the parameters of transmission cable harmonic transfer coefficient and the allowable emission value of power quality pollution of the urban power grid are deduced and quantitatively analyzed. Then the harmonic transmission and mutual influence of urban power network harmonics in power transmission cable are analyzed through examples, which is helpful to determine the allowable value of harmonic pollution emission scientifically and reasonably.

Cellulose particles are among the aging products of the insulating paper that are used in power transformers. Too many cellulose particles can cause transformer accidents. Traditional research and detection methods that are used for this problem generally focus on the number and length information of cellulose particles, and it is usually difficult to quantitatively describe the spatial shape of cellulose particles. However, the shape of cellulose particles is also one of the factors affecting the safety of transformer insulation. In this paper, we successfully extracted quantitative information of the spatial shape of cellulose particles in transformer oil using an image processing technique and the transport of intensity equation, providing a new novel approach for the study and detection of the shape of cellulose particles in transformer oil.

Recently, various types of porous surfaces have been demonstrated for lubricant (e.g., oil) impregnated omniphobic surfaces. However, the retention of the lubricating liquid within the porous layer and the omniphobic durability still remain challenges. Here, the omniphobic durability of the oil-impregnated surfaces of various types of anodic aluminum oxide (AAO) nanostructures is investigated. The oil impregnation into nanoporous AAO with high porosity enhances droplet mobility by eliminating the pinning site of a contact line on the solid surface, whereas that with low porosity allows the pinning site to result in less mobility. In the cases of nanopillared AAO layers, although the oil-impregnation enhances the repellency to liquids, oil is prone to be depleted by external force such as fluid flow due to the nature of the interconnected oil through the passages between pillars, which limits the omniphobic durability. Among the various types of nanostructured AAO surfaces, the AAO with isolated pore geometry with high porosity exhibits the most durable omniphobicity for a wide range of liquids including organic liquids with low surface tensions. Moreover, the nanoporous AAO surface shows great anti-bacterial adhesion property, reducing the adhesion of bacteria (Escherichia coli K-12) up to 99.2% compared to a bare aluminum surface.

Understanding how surface properties determine the mobility of a fakir droplet on patterned surfaces, which is typically characterized by advancing and receding contact angles, is important in the design of superhydrophobic surfaces for tailored applications. However, most analytical models of the contact angles are limited to a specific motion direction and surface type, e.g., receding on a pillared surface. Although it was suggested that the contact angles should be determined by the local configuration and dynamics of the droplet boundary, their link remains vague due to the lack of detailed visualizations. In this study, the contact line dynamics of a fakir droplet in both advancing and receding motions on not only micropillared but also micropored surfaces are visualized in reflection interference contrast microscopy along with the contact angle measurement. Based on the energy change induced by the displacement of a contact line and the deformation of a liquid-gas interface in between contact lines, theoretical models of the contact angles to encompass the two different motion directions and surface types are formulated. Moreover, further generalized models are established to serve as effective analytical models to predict the contact angles only based on the given structure dimensions and the inherent surface hydrophobicity.

Background Researches on programmed cell death (PD-1) as neoadjuvant immunotherapy for resectable non-small cell lung cancer is underway, which brings hope for individuals with the disease. However, a study dedicated to lung squamous cell carcinoma (LUSC) specifically has yet to be conducted. Now, data from our pilot prospective research neoadjuvant study provide new insights in the field of neoadjuvant regimen for LUSC. Methods Between June 2019 and July 2020, 37 adults with untreated, surgically resectable stage IIB-IIIB LUSC were enrolled into this prospective study. Patients received 2 cycles of pembrolizumab (2 mg/kg) with chemotherapy (albumin-bound paclitaxel 100 mg/m2 on days 1 and 8 + carboplatin AUC 5) via intravenous administration every 3 weeks, and underwent surgical treatment 3-4 weeks after the second cycle. The primary endpoint of the study was the tumor pathologic complete response (pCR) rate. The toxicity profile, tumor major pathological remission, complete resection rate, response rate, and operative and postoperative complications were also evaluated. Results The postoperative pathological specimens of 17 (45.9%) patients suggested pCR. Neoadjuvant pembrolizumab with chemotherapy had an acceptable side-effect profile, and no patients withdrew from the study preoperatively due to disease progression or toxicity. A major pathological response occurred in 24 (64.9%) resected tumors. All tumors were completely resected (R0, 100%). According to the Response Evaluation Criteria in Solid Tumors (RESIST), a response was evaluated before surgery in 32 (86.5%) patients by computed tomography. Twenty-five (67.6%) patients underwent thoracoscopic surgery. No deaths or postoperative major complications requiring reoperation occurred. Recurrence or metastasis was found in 2 patients during follow-up of 2-14 months. Conclusions The early outcomes of pembrolizumab with chemotherapy in the neoadjuvant setting as a novel treatment for resectable stage IIB-IIIB LUSC showed a high pCR rate that has not been seen previously, as well as a high R0 resection rate and a low toxicity profile. The long-term efficacy of this novel treatment and the validity of the present findings should be confirmed with longer follow-up and prospective comparative trials.

For applications involving droplet detachment from solid surfaces, it is vital to study the droplet characteristics (e.g., contact angle and base width) when the droplet is experiencing the maximum force that detaches the droplet (maximum adhesion state). Historically, such investigations were mainly conducted on flat two-dimensional surfaces and the characteristics on curved surfaces with the third dimension remain unknown. Thus, the generalized description of such characteristics has not been established yet. Here, by vertically pulling liquid droplets using a microbalance, we study the droplet characteristics at the maximum adhesion on curved homogeneous surfaces. Variables in this study include liquid surface tension, initial droplet base area, and the asymmetry in solid surface curvature. Results show that the contact angle is identical everywhere along the droplet perimeter on curved surfaces irrespective of the asymmetry in surface curvature. In addition, we found that the droplet base is nonaxisymmetric (not circular) at the maximum adhesion, opposing previous understanding that was formulated for flat surfaces. As a result, we propose a more generalized and quantitative description of the droplet characteristics at the maximum adhesion, derived from the component of the surface tension force acting along the droplet perimeter.

BackgroundInvasive mucinous adenocarcinoma (IMA) of the lung is a distinct histological subtype with unique clinical and pathological features. Despite previous genomic studies on lung IMA, the genetic characteristics and the prognosis-related biomarkers in Chinese surgically resected lung IMA remain unclear.MethodsWe collected 76 surgically resected primary tumors of invasive lung adenocarcinoma, including 51 IMA and 25 non-mucinous adenocarcinomas (non-IMA). IMA was further divided into pure-IMA (mucinous features≥90%) and mixed-IMA subgroups. Comprehensive genomic profiling based on targeted next-generation sequencing (NGS) of 425 genes was explored and genomic characteristics were evaluated for the correlation with postoperative disease-free survival (DFS).ResultsIMA had a unique genetic profile, with more diverse driver mutations and more tumor drivers/suppressors co-occurrence than that of non-IMA. The frequency of EGFR (72.0% vs. 40.0% vs. 23.1%, p=0.002) and ALK (undetected vs. 20.0% vs. 26.9%, p=0.015) alterations showed a trend of gradual decrease and increase from non-IMA to mixed-IMA to pure-IMA, respectively. The frequency of KRAS mutations in pure-IMA was higher than that in mixed-IMA, albeit statistically insignificant (23.1% vs. 4.0%, p=0.10). TP53 mutation was significantly less in pure-IMA compared to mixed-IMA and non-IMA (23.1% vs. 52.0% vs. 56.0%, p=0.03). Besides, IMA exhibited less arm-level amplifications (p=0.04) and more arm-level deletions (p=0.004) than non-IMA, and the frequency of amplification and deletion also showed a trend of gradual decrease and increase from non-IMA to mixed-IMA to pure-IMA, respectively. Furthermore, prognosis analysis in stage III IMA patients showed that patients harboring alterations in EGFR (mDFS=30.3 vs. 16.0 months, HR=0.19, P=0.027) and PI3K pathway (mDFS=36.0 vs. 16.0 months, HR=0.12, P=0.023) achieved prolonged DFS, while patients with poorly differentiated tumors (mDFS=14.1 vs. 28.0 months, HR=3.75, p=0.037) or with KRAS mutations (mDFS=13.0 vs. 20.0 months, HR=6.95, p=0.027) had shorter DFS. Multivariate analysis showed that KRAS mutations, PI3K pathway alterations, and tumor differentiation status were independent factors that have statistically significant influences on clinical outcomes of IMA patients.ConclusionOur study provided genomic insights into Chinese surgically resected lung IMA. We also identified several genomic features that may serve as potential biomarkers on postoperative recurrence in IMA patients with stage III disease.

Lung cancer (LC) ranks first among all causes of cancer-related death, with non-small cell lung cancer (NSCLC) taking up 85% of lung cancer cases. Although lncRNA MCM3AP antisense RNA 1 (MCM3AP-AS1) has been reported to be an oncogenic factor in NSCLC, its detailed mechanism in NSCLC is unknown. In this study, quantitative real-time polymerase chain reaction (qRT-PCR) was performed to determine MCM3AP-AS1, microRNA (miR)-195-5p and E2F transcription factor 3 (E2F3) mRNA expressions in NSCLC tissues and cells. Western blot was utilized to determine the expression levels of E2F3, BCL2-associated X protein (Bax), B-cell lymphoma-2 (Bcl-2), E-cadherin and N-cadherin. CCK-8 and Transwell assays were conducted to examine cell proliferation, migration and invasion, respectively. Dual-luciferase reporter assay and RNA immunoprecipitation experiments were used to determine the regulatory relationships between MCM3AP-AS1 and miR-195-5p, and miR-195-5p and E2F3. We demonstrated that MCM3AP-AS1 was overexpressed in NSCLC tissues and cells, and MCM3AP-AS1 overexpression accelerated the proliferation, migration and invasion of NSCLC cells. In addition, MCM3AP-AS1 overexpression markedly up-modulated Bcl-2 expression and repressed Bax expression; MCM3AP-AS1 overexpression also significantly up-regulated N-cadherin expression and suppressed E-cadherin expression in NSCLC cells. What is more, in NSCLC cells, miR-195-5p was a target of MCM3AP-AS1, and the latter worked as a molecular sponge for miR-195-5p to regulate E2F3 expression. Collectively, MCM3AP-AS1, serving as a competitive endogenous RNA (ceRNA) to regulate miR-195-5p/E2F3 axis, promotes NSCLC progression, which is a promising therapeutic target for NSCLC., Graphical bastract

Background The incidence rate of adenocarcinoma of the esophagogastric junction (AEG) has significantly increased over the past two decades. Surgery remains the only curative treatment. However, there are currently few studies on Chinese AEG patients. The purpose of this study was to retrospectively analyze the survival and prognostic factors of AEG patients in our center. Methods Between January 2008 and September 2014, 249 AEG patients who underwent radical resection were enrolled in this retrospective study, including 196 males and 53 females, with a median age of 64 (range 31–82). Prognostic factors were assessed with the log-rank test and Cox univariate and multivariate analyses. Results The 5-year survival rate of all patients was 49%. The median survival time of all enrolled patients was 70.1 months. Pathological type, intraoperative blood transfusion, tumor size, adjuvant chemotherapy, duration of hospital stay, serum CA199, CA125, CA242 and CEA, pTNM stage, lymphovascular or perineural invasion, and the ratio of positive to negative lymph nodes (PNLNR) were significantly associated with overall survival when analyzed in univariate analysis. Conclusions Our study found that adjuvant chemotherapy, PNLNR, intraoperative blood transfusion, tumor size, perineural invasion, serum CEA, and duration of hospital stay after surgery had significance in multivariate analysis and were independent risk factors for survival.

Droplet generation in a T-junction with surfactants is simulated using our recently developed lattice Boltzmann method. The method is first used to explore the effect of surfactant concentration [Formula: see text] on droplet generation. As [Formula: see text] increases, droplet generation tends to shift from squeezing to dripping regime and then to jetting regime. In the clean system, the upstream pressure varies almost periodically with time. However, in the surfactant-laden system, the upstream pressure no longer varies periodically but overall increases with time for droplet generation in squeezing and dripping regimes. This is because the addition of surfactants results in an additional pressure drop between the front and rear of the generated droplet. Then, droplet generation in both clean and surfactant-laden systems is compared to explore the surfactant role under different values of the capillary number [Formula: see text]. In either clean or surfactant-laden system, the pressure upstream of the junction rapidly decreases as [Formula: see text] increases. In the presence of surfactants, the upstream pressure overall increases with time for droplet generation in squeezing and dripping regimes, but the increased amplitude decreases with [Formula: see text]. Finally, we establish the phase diagrams describing how the droplet generation regime varies with flow rate ratio and [Formula: see text] in both clean and surfactant-laden systems. It is found that the addition of surfactants reduces the critical capillary number distinguishing squeezing from dripping and the critical capillary number distinguishing dripping from jetting.

BACKGROUND: The gut microbiome is associated with the response to immunotherapy in a variety of advanced cancers. However, the influence of the gut microbiome on locally advanced esophageal squamous cell carcinoma (ESCC) during programmed cell death protein 1 (PD-1) antibody immunotherapy plus chemotherapy is not clearly demonstrated. To explore the crosstalk between the gut microbiome and clinical response in locally advanced thoracic ESCC during neoadjuvant camrelizumab and chemotherapy METHODS: Patients who were diagnosed with locally advanced thoracic ESCC and had not received treatment were enrolled. The treatment regimen was two cycles of camrelizumab combined with carboplatin and albumin paclitaxel before surgery. The research endpoints were pathological complete response (pCR) and major pathological response (MPR). Fecal samples were collected at three time points: before neoadjuvant therapy, after two cycles of neoadjuvant therapy, and after surgery. We performed 16S ribosomal ribonucleic acid (rRNA) V3–V4 sequencing of the gene amplicons of fecal samples, as well as bacterial diversity and differential abundance analyses. RESULTS: A total of 46 patients were recruited, and 44, 42, and 35 fecal samples were collected at the three time points, respectively. Statistically significant differences were observed in the amplicon sequence variant (ASV)-level alpha diversity indices, including Chao1, Shannon, and Good’s coverage, between the three time points. The non-pCR-enriched gut microbiota included Proteobacteria, Dialister, Aeromonadales, Pseudomonadales, Thermi, Deinococci, Moraxellaceae, Rhodocyclales, Rhodocyclaceae, and Acinetobacter. The non-MPR-enriched gut microbiota included Pseudomonadales and the mitochondria family. The MPR-enriched gut microbiota included the Barnesiellaceae, Pyramidobacter, Dethiosulfovibrionaceae, Odoribacteraceae, Butyricimonas, Prevotella, Barnesiella, and Odoribacter. Patients with ≥3 grade adverse events (AEs) exhibited enrichment in the Succiniclasticum, Nakamurella, Rhizobium, Granulicella, Phyllobacteriaceae, Pelagibacteraceae, Actinosynnemataceae, Aquirestis, Flavisolibacter, Chelativorans, Coxiellaceae Acidicapsa, Acidobacteriaceae, Lentzea, Staphylococcus, Plesiomonas, Dysgonomonas, Pseudonocardia, and Ellin6075. CONCLUSIONS: We found that the diversity of the gut microbiome declined after neoadjuvant PD-1 antibody immunotherapy plus chemotherapy and surgery. Patients with pCR had different types and proportions of gut microbiota before treatment compared to those without pCR. We also observed the difference between patients with or without ≥ grade 3 AEs. The taxonomic features of the gut microbiome are potential biomarkers that could predict the pathological response and AEs.

278 Background: To explore the efficacy and safety of neoadjuvant camrelizumab and chemotherapy for locally advanced thoracic esophageal squamous cell carcinoma (ESCC) by an open label, single-arm, phase 2 clinical trial (ClinicalTrials.gov, Identifier number: NCT04506138). Methods: The eligible patients were arranged to receive 2 cycles of camrelizumab (200mg, day 1) combined with carboplatin (AUC = 5, day 1) and albumin paclitaxel (100 mg/m2, day 1, 8). All treatments were given intravenously in 3-week cycle. Patients underwent surgery within 4-6 weeks after the completion of neoadjuvant treatment. The primary endpoint was pathologic complete response (pCR), and secondary endpoints were major pathological response (MPR), safety and feasibility. The quality of life (QoL) was assessed by the Functional Assessment of Cancer Therapy-Esophageal (FACT-E) scale and EQ-5D-3L scale. Results: A total of 46 patients were recruited, among whom the clinical stage II, III, and IVa at baseline were 11 (23.9%), 33 (71.7%), and 2 (4.3%), respectively. Forty-five patients completed 2 cycles of neoadjuvant treatment. One patient received 1 cycle of neoadjuvant treatment and then lost to be followed up. Eight patients did not receive surgery. Except 1 patient accept exploratory surgery, 37 patients (37/46, 80.4%) achieved R0 resection. Eight patients (8/37, 21.6%) had pCR in both primary tumors and lymph nodes. MPR of primary tumors and lymph nodes was observed in 18 patients (18/37, 48.6%). During neoadjuvant treatment period, all 46 patients presented with treatment-related AEs (TRAEs) of any grade. Seven patients (7/46,15.2%) experienced grade ≥ 3 TRAEs. One patient suffered grade 5 immune-associated pneumonia. The most common TRAEs were anemia (32/46, 70.0%), followed by thrombocytopenia (15, 32.6%), leukopenia (14, 30.4%), neutropenia (13, 28.3%), rash (12, 26.1%), reactive cutaneous capillary endothelial proliferation (RCCEP) (7, 15.2%). The median interval between the first cycle of neoadjuvant treatment and surgery was 64 days (range, 56-77 days). Symptom scores in FACT-E scale were improved by neoadjuvant treatment (t = -2.60, P = 0.01). PD-L1 CPS (< 10 vs ≥ 10), PD-L1 TPS (< 1% vs ≥ 1%) and TMB (split according to top 20% of TMB value) had no effect on the pCR rate and MPR rate. Conclusions: Neoadjuvant camrelizumab combined with chemotherapy achieved a promising pathologic response, which was effective and safe. Meanwhile, neoadjuvant treatment improved QoL of patients. Some larger multi-center trials are undergoing for further confirmation of efficacy and safety. Clinical trial information: NCT04506138.

Railway static power conditioner(RPC) can effectively overcome the shortcomings of traditional conditioner which has poor negative sequence and harmonic compensation effect, it provides a new way to control the power quality of high-speed railway. However, the traditional two-level RPC device occupies a large area, and it will also encounter direct current bias magnetic problem, which distorts the voltage of the system and the excitation current distorts to form peak waves. At this time, the harmonic content increases dramatically and the reactive power loss of the transformer increases. In this paper, the MMC topology and RPC structure are combined to form the MMC-RPC topology, which is directly connected to the traction power supply arm, eliminating such deficiencies as large floor area, large loss and distortion of output current waveform of the booster transformer. At the same time, this paper also studied the capacitor voltage equalization control and circulation suppression strategy of MMC-RPC topology. Finally, the MMC-RPC topology simulation model is built to verify the feasibility and effectiveness of the topology structure and control strategy.

Although freezing of a droplet on cold surfaces is a universal phenomenon, its mechanisms are still inadequately understood, especially on the surfaces of which the temperature is lower than -60 °C. Here, we report the unique spontaneous deicing phenomena of a water droplet impacting on cold surfaces with a temperature as low as -120 °C. As a hydrophilic surface is cooled below a critically low temperature (e.g., -57 °C for a silicon surface with a native oxide), the impacting water droplet spontaneously delaminates from the substrate and freezes radially outward in a horizontal plane, as opposed to the typical upward freezing shown on a warmer surface. The self-delamination phenomenon is suppressed or reinstated by the combination of thermal and hydrophobic modifications of the surface, which can be taken advantage of for effective deicing schemes for icephobic surface applications.

Scratch is a popular programming platform with plenty of learning resources. However, it is quite difficult for users to find suitable resources. In this paper, in order to provide the resources which the users require, we propose a Scratch Recommendation Framework Adaptive to User Interest Drifts (SRFA-UID). First, a user interest drifts model is designed, which adopts the time decay factor and the weights of operation behaviors to track users' dynamic interest. Then, on the basis of users' current and historical interest, we calculate their combined user similarity. Next, we present a novel two-hop-algorithm to update users' friend community. Considering the preferences of the whole friend community, the Computational Thinking (CT) skills of users and the impact factors of items, we put forward a recommendation function to obtain items that are related to users. For an item, the function can calculate its F value to determine if we can recommend it to the users. Experimental results show that SRFA-UID performs better than other state-of-the-art methods in the Scratch dataset.

The mobility of a fakir state droplet on a structured surface is fundamentally determined by the effective length of a microscopic contact line. However, it is largely unknown how the surface topography determines the effective contact line length. Based on the direct measurement of droplet adhesion force and the visualization of contact line, this work shows that effective contact line length is topography dependent as opposed to prior notion. On pored surfaces, contact line is not distorted, and the effective length approaches the droplet apparent perimeter regardless of pore dimensions. On pillared surfaces, the distortion of contact line is significantly dependent on the packing density of the pillar structures so that the effective length is as small as a pillar diameter on densely packed pillars and as large as a pillar perimeter on sparsely-packed pillars, while changing linearly between the two extremes.

Advances made in fabrication of patterned surfaces with well-defined dimensions of topographic features and their lateral dissemination drive the progress in interpretation of liquid spreading, adhesion, and retreat on engineered solid surfaces. Despite extensive studies on liquid droplet spreading and adhesion on textured surfaces in recent years, conformation of the three-phase contact line and its effect on macroscopic contact angle and droplet adhesion remain the focus of intensive debate. Here, we investigate the effect of surface topography on the adhesion force of Cassie-Baxter-state droplets on concentric ring-textured hydrophobic surfaces having rings with lateral dimensions of 5, 10, and 45 μm and separated by 5, 6, and 7 μm trenches, respectively, with fixed depth of 15 μm. Unlike mostly tested surfaces textured with straight ridges, pores, and pillars, where the droplet base contact line is anisotropic and its conformation varies along the apparent boundary, concentric rings are symmetrical and reinforce the microscopic contact line to align to a circular one that reflects the shape of the pattern. In this study, adhesion forces were calculated based on surface tension and Laplace pressure forces and were compared with the experimental forces for both water and ethylene glycol droplets having a varying contact diameter on the concentric ring-pattern at the point of maximum adhesion force. Results show that the microscopic contact line of the liquid retains its circular shape controlled by circular rings of the pattern, irrespectively of the droplet base diameter larger than 0.8 mm, and there is a good agreement between the experimental and calculated adhesion forces.

Surface tension and capillary forces were measured for water droplets in contact with anisotropic hydrophobic patterns made of microscopic ridges and grooves using a microbalance. Integrated with a charge-coupled device camera, the instrument allowed capturing of the synchronous images of a droplet during its spreading, compression, stretching and detachment. These images were used to analyze the evolution of the droplet shape and quantify its base diameter and contact angle in both the longitudinal and traverse directions. The experiments confirmed that a water droplet spreads preferentially along the longitudinal direction, on top of the ridges, following the continuity of the solid and producing asymmetry in the drop shape. Switching the droplet wetting mode from advancing to receding causes the droplet to symmetrize its shape. It was found that the maximum adhesion between the droplet and hydrophobic pattern coincides with droplet base circularity and apparent contact angles of nearly identical values measured in the longitudinal and traverse directions. These findings confirm that the most stable configuration for a liquid droplet on a rough solid surface appears only when the droplet base is axisymmetric. It is also demonstrated that the Cassie–Baxter equation pertains only to the droplet in the most stable state, where the excess free energy is minimized.

Spontaneous spreading of a droplet on a solid surface is poorly understood from a macroscopic level down to a molecular level. Here, we investigate the effect of surface topography and wettability on spontaneous spreading of a water droplet. Spreading force is measured for a suspended droplet that minimizes interference of kinetic energy in the spontaneous spreading during its contact with solid surfaces of discontinuous (pillar) and continuous (pore) patterns with various shapes and dimensions. Results show that a droplet cannot spread spontaneously on pillared surfaces regardless of their shapes or dimensions because of the solid discontinuity. On the contrary, a droplet on pored surfaces can undergo spontaneous spreading whose force increases with a decrease in the advancing contact angle. Theoretical models based on both the system free energy and capillary force along the contact line validate the direct and universal dependency of the spontaneous spreading force on the advancing contact angle.

Haiyang Wang,1,* Xiaoqing Yu,1,* Yun Fan,2 Youhua Jiang2 1Department of Second Clinical Medical College, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, People’s Republic of China; 2Key Laboratory of Diagnosis and Treatment Technology on Thoracic Oncology (Esophagus, Lung), Zhejiang Cancer Hospital, Hangzhou, Zhejiang, People’s Republic of China *These authors contributed equally to this work Background: There are many controversies concerning the best management of epidermal growth factor receptor (EGFR)-mutant non-small-cell lung cancer (NSCLC) patients with brain metastases (BMs). The use of upfront EGFR tyrosine kinase inhibitors (TKIs) and the withholding of local therapies or upfront radiation therapies (RTs) remain controversial. Available treatment options include local therapies such as whole-brain radiation therapy (WBRT), stereotactic radiosurgery (SRS) and surgery, EGFR-TKIs, and chemotherapy. However, the optimal management of combination therapies is still under consideration. Patients and methods: A total of 45 EGFR-mutated NSCLC patients with BMs were included. All patients successively received EGFR-TKIs, RT (WBRT or SRS), and chemotherapy between 2010 and 2015 at Zhejiang Cancer Hospital. Patient follow-up was conducted by telephone until February 2017. The treatment response was evaluated, and survival data were collected and analyzed by Kaplan–Meier analysis and the Cox regression method. Results: The median overall survival (OS) was 28 months. Patients with the exon 19 deletion showed the strongest trend toward a longer median OS compared to patients with the exon 21 L858R mutation (not reached vs 26.5 months,P=0.0969). There was no difference in OS between the upfront RT group and the deferral group (26.5 vs 28 months,P=0.57), and similar results were found between the first-line chemotherapy group and the EGFR-TKI group (28 vs 23.2 months, P=0.499). In multivariate analysis, the prognosis correlated with EGFR mutation type (P=0.017). Conclusion: EGFR-mutant NSCLC patients with BM benefited from the combination and sequential therapies of EGFR-TKIs, chemotherapy, and RTs. Patients with the EGFR exon 19 deletion may have a better OS. However, the optimal timing of RT interval remains to be explored. Keywords: epidermal growth factor receptor, tyrosine kinase inhibitors, brain metastases, non-small-cell lung cancer, pemetrexed, whole-brain radiation therapy

A directional bending sensor based on thin-core fiber Bragg grating is proposed and demonstrated experimentally. It is inscribed by off-center technique and exposed by 193 nm ArF excimer laser through a phase mask. A series of cladding modes are excited and their intensities are enhanced to about 10 dB. The formation mechanism of those cladding modes is discussed and analyzed. The intensities of these cladding mode resonances is detected for bending and direction with maximum sensitivity 1.93 dB/m 1 at 0 ° to − 1 . 95 dB/m 1 at 180 ° under the curvature varied from 0 m−1to 2.5 m−1. The sensitivity of surrounding temperature is 11.3pm/°C ranging from 25 °C to 60 °C. This all-fiber structure has a great advantage for fiber orientation identification sensor with more convenient manufacture and needless de-localize FBGs.

A simple and reliable method by combination of sensing coating and interferometric optical microfiber to detect the concentration of ammonia is reported in this study. The sensor is fabricated by coating the tapered microfiber interferometer (MFI) with zinc oxide nanoparticle incorporated graphene oxide (GO-ZnO). GO-ZnO nanocomposites serving as an electron acceptor trap electrons after ammonia absorption and then change the surface refractive index of the optical microfiber in MFI. Subsequently, the MFI translates the tiny refractive index change into wavelength shift of the transmission spectra. As prepared sensor exhibits a good repeatability and high sensitivity to ammonia with different connections from 4 ppm to 140 ppm at room temperature. The gas sensor response to ammonia has been studied in different moisture level and show reliable operation in low humidity atmosphere. In addition, the gas sensor also displays an excellent selectivity to ammonia compared to several possible interfering volatile organic compounds. This may be attributed to the selective ammonia absorption at the GO-ZnO surface and the additional synergistic effects of GO-ZnO nanocomposites that are desirable and advantageous for gas sensing.

A one-step maskless oxygen plasma etching process is investigated to nanopattern conjugated polymer dodecylbenzenesulfonate doped polypyrrole (PPy(DBS)) and to examine the effects of nanostructures on the inherent tunable wettability of the surface and the droplet mobility. Etching characteristics such as the geometry and dimensions of the nanostructures are systematically examined for the etching power and duration. The mechanism of self-formation of vertically aligned dense-array pillared nanostructures in the one-step maskless oxygen plasma etching process is also investigated. Results show that lateral dimensions such as the periodicity and diameter of the pillared nanostructures are insensitive to the etching power and duration, whereas the length and aspect ratio of the nanostructures increase with them. X-ray photoelectron spectroscopy analysis and thermal treatment of the polymer reveal that the codeposition of impurities on the surface resulting from the holding substrate is the primary reason for the self-formation of nanostructures during the oxygen plasma etching, whereas the local crystallinity subject to thermal treatment has a minor effect on the lateral dimensions. Retaining the tunable wettability (oleophobicity) for organic droplets during the electrochemical redox (i.e., reduction and oxidization) process, the nanotextured PPy(DBS) surface shows significant enhancement of droplet mobility compared to that of the flat PPy(DBS) surface with no nanotexture by making the surface superoleophobic (i.e., in a Cassie-Baxter wetting state). Such enhancement of the tunable oleophobicity and droplet mobility of the conjugated polymer will be of great significance in many applications such as microfluidics, lab-on-a-chip devices, and water/oil treatment.

A simple and sensitive optical fiber relative humidity (RH) sensor is proposed and demonstrated in this paper. The optical microfiber inter-mode interferometer is fabricated by tapering PM-elliptical core fiber down to micrometer scale in diameter, the coupling mainly occurs between the LP01 and LP11 modes. The microfiber interferometer (MFI) is fixed as U-shape, making it conveniently to measure. The RH changes are determined from the wavelength shift of the interference pattern induced by the evanescent-field interaction. Experimental results show that MFI with a thinner diameter of $4.7~\mu \text{m}$ offers the best RH sensitivity of 114.7 pm/RHU (per relative humidity unit) ranging from 30% to 90% and good linearity between wavelength and RH. The temperature response has also been experimentally studied, and the temperature sensitivity is 7.6 pm/°C from 30 °C to 90 °C, which indicates that this microfiber device possesses a low temperature cross sensitivity. The proposed RH sensor does not need any functional coating, with advantages of compact size and simple fabrication procedure, which make it attractive for several applications.

Fog collection is a promising solution to the worldwide water scarcity problem and is also of vital importance to industrial processes, such as recapturing water in cooling towers and mist elimination. To date, numerous studies have investigated the fog collection rate, a parameter that denotes the average performance over a long period of time. However, the initial period (referred to as onset time) between the start of the fog-laden flow and the actual collection of the captured liquid (a delay in time caused by droplet growth to a critical weight that exceeds droplet-surface retention force) has not been systematically understood. A longer onset time may result in a more serious clogging issue that deteriorates the collection rate and, hence, understanding this phenomenon is important. Here, we study how the onset time is determined by the capture and transport of fog using individual, vertical wires with various surface wettabilities and diameters, under different wind speeds. This approach allows us to derive a scaling law that correlates the onset time with the fog capture process and droplet-surface retention force, governed by aerodynamics and interfacial phenomena, respectively. In particular, the onset time decreases with an increasing rate of fog capture or a decreasing droplet-surface retention force. This study introduces an important aspect in the evaluation of fog collection and provides insights for the optimal design of fog collectors and mist eliminators.

It was experimentally shown that a depinning force of a receding droplet on a micropillared superhydrophobic surface has an apparently linear correlation with the maximal three-phase contact line attainable along an actual droplet boundary. However, the experimental observation has not yet been supported by any theoretical basis or analysis. This study establishes an analytical model that theoretically supports the experimental observation on the basis of the dynamics of a contact line. The depinning force of a receding droplet was experimentally measured in evaporation on micropillared superhydrophobic surfaces with varying structure pitches but a fixed size. The analytical model was established by considering the energy dissipated by the displacement of a microscopic contact line on pillar tops and the energy consumed for the distortion of a liquid-gas interface between pillar tops. The model shows that the depinning force can theoretically be estimated by the physical dimensions of pillars and the intrinsic hydrophobicity of the surface, showing excellent agreement with the experimental results. Especially, the model indicates that the depinning force is fundamentally determined and practically controllable by the normalized maximal contact line at the droplet boundary, which can effectively be represented as the ratio of the pillar top perimeter to pitch.