Estimation of Wind Speed Based on Schlieren Machine Vision System Inspired by Greenhouse Top Vent.

Greenhouse ventilation has always been an important concern for agricultural workers. This paper aims to introduce a low-cost wind speed estimating method based on SURF (Speeded Up Robust Feature) feature matching and the schlieren technique for airflow mixing with large temperature differences and density differences like conditions on the vent of the greenhouse. The fluid motion is directly described by the pixel displacement through the fluid kinematics analysis. Combining the algorithm with the corresponding image morphology analysis and SURF feature matching algorithm, the schlieren image with feature points is used to match the changes in air flow images in adjacent frames to estimate the velocity from pixel change. Through experiments, this method is suitable for the speed estimation of turbulent or disturbed fluid images. When the supply air speed remains constant, the method in this article obtains 760 sets of effective feature matching point groups from 150 frames of video, and approximately 500 sets of effective feature matching point groups are within 0.1 difference of the theoretical dimensionless speed. Under the supply conditions of high-frequency wind speed changes and compared with the digital signal of fan speed and data from wind speed sensors, the trend of wind speed changes is basically in line with the actual changes. The estimation error of wind speed is basically within 10%, except when the wind speed supply suddenly stops or the wind speed is 0 m/s. This method involves the ability to estimate the wind speed of air mixing with different densities, but further research is still needed in terms of statistical methods and experimental equipment.

Parametric modeling study for blown-dust secondary pollution and optimal ventilation velocity during tunnel construction.

Tunnel construction often relies on drilling and blasting. High dust pollution is one of the primary problems of drilling and blasting construction. The level of secondary blown dust pollution caused by ventilation matches that of dust pollution caused by drilling construction. In this study, a critical flow model and blown dust rate model for deposited dust were established via force analysis, which was validated against the test data. The research results showed that the characteristic airflow velocity for blowing dust particles with a 100 µm diameter reached approximately 0.42 m/s for tunnel diameter is 10 m, and the ventilation Re values under smooth and rough conditions were 2.3 × 105 and 1.4 × 105, respectively. Furthermore, when ventilation Re reached 4 × 105, the blown dust pollution rate caused by ventilation under smooth conditions was approximately 1.8 × 10-2 kg/s. If dust particle size is more or less the critical dust particle size, the characteristic airflow velocity was increased. Moreover, the optimal velocity at which the deposited dust does not flow or move during tunnel construction was related to the tunnel size and roughness. For the smooth tunnel with a diameter of 10 m, the optimal ventilation velocity was 3.5 m/s. When the tunnel roughness was increased from 0.005 to 0.5 m, the optimal ventilation velocity decreased from 3.3 to 1.6 m/s. The deposited dust critical flow model and blown dust pollution rate model established in this study provide a sound theoretical basis for selecting the optimal velocity of tunnel ventilation and recognizing the risks of secondary blown dust pollution due to ventilation.

Adaptive Wall-Based Attachment Ventilation: A Comparative Study on Its Effectiveness in Airborne Infection Isolation Rooms with Negative Pressure.

The transmission of coronavirus disease 2019 (COVID-19) has presented challenges for the control of the indoor environment of isolation wards. Scientific air distribution design and operation management are crucial to ensure the environmental safety of medical staff. This paper proposes the application of adaptive wall-based attachment ventilation and evaluates this air supply mode based on contaminants dispersion, removal efficiency, thermal comfort, and operating expense. Adaptive wall-based attachment ventilation provides a direct supply of fresh air to the occupied zone. In comparison with a ceiling air supply or upper sidewall air supply, adaptive wall-based attachment ventilation results in a 15%-47% lower average concentration of contaminants, for a continual release of contaminants at the same air changes per hour (ACH; 10 h-1). The contaminant removal efficiency of complete mixing ventilation cannot exceed 1. For adaptive wall-based attachment ventilation, the contaminant removal efficiency is an exponential function of the ACH. Compared with the ceiling air supply mode or upper sidewall air supply mode, adaptive wall-based attachment ventilation achieves a similar thermal comfort level (predicted mean vote (PMV) of -0.1-0.4; draught rate of 2.5%-6.7%) and a similar performance in removing contaminants, but has a lower ACH and uses less energy.

A new model based on gamma-glutamyl transpeptidase to platelet ratio (GPR) predicts prognostic outcome after curative resection of solitary hepatocellular carcinoma.

BACKGROUND: This study intends to explore the potential clinical value of gamma-glutamyl transpeptidase to platelet ratio (GPR) and the new multi-factor scoring model for recurrence and prognosis prediction in solitary HCC patients who received radical resection. METHODS: This study retrospectively analyzed 295 HCC patients after curative resection. According to the Receiver Operating Characteristic (ROC) curve, the optimal cut-off value of GPR for predicting prognosis of HCC after resection was determined. The Kaplan Meier method and Cox regression analysis were performed to assess the important potential factors in the prognosis of HCC and determine the independent risk factors. Assign a value to each independent risk factor and establish a new scoring model. Then, using GPR and the new scoring model to evaluate overall survival (OS) and postoperative recurrence probability. RESULTS: When GPR's cut-off value was selected as 0.30, its predictive efficiency for postoperative prognosis was more favorable than those of other cut-off values (0.76, 0.84 and 0.94). GPR, tumor size, microvascular invasion and neutrophil to lymphocyte ratio (NLR) were identified as independent prognostic predictors. Using these variables, a novel prognostic scoring model was devised and established to identify different levels of risk: high, intermediate and low risk groups. We found that patients with high GPR level and of high risk group would have a poorer OS and a higher recurrence rate after radical resection. CONCLUSIONS: GPR may serve as a promising predictor for postoperative prognosis and recurrence probability of HCC, and the new prognostic scoring model may be available for postoperative management among HCC patients.

Temporal variation of airborne fungi in university library rooms and its relation to environmental parameters and potential confounders.

Indoor airborne fungi have been associated with adverse human health effects. Therefore, it is important to understand the causes of underlying variation in airborne fungi in indoor environments. This study consequently aimed to investigate the association between indoor fungi with temporal variation, environmental parameters, and potential confounders over 10 months in four library rooms using Andersen samplers. Indoor fungal concentrations peaked in October and were lowest in March in both stack rooms, whereas the highest concentrations in both reading rooms were observed in September with lowest concentrations in July. Nonparametric analyses revealed higher fungal concentrations in the rooms that were significantly associated with relative humidity ≥ 60%, PM2.5 ≥ 35 µg/m3, number of people ≥ 16, open windows, working air conditioners, and room area < 400 m2. Multiple linear regression modeling for the library building considering only continuous variables revealed that relative humidity, PM2.5, and the number of people were significant predictors of fungal concentrations. Additionally, the model with continuous and categorical variables suggested that relative humidity, PM2.5, the number of people, ceiling fan condition, window state, and air conditioner operating status were significant predictor variables of concentrations. Outdoor fungal concentrations were a significant predictor for the two models of indoor fungal concentrations for each room. Ceiling fan or air conditioner operation was associated with altered fungal particle concentrations. These results provide a deeper understanding of indoor air fungal quality.

Research on a personalized targeted air supply device based on body movement capture.

Unlike general ventilation, personalized ventilation can improve thermal comfort and conserve energy based on individual differences. It can also provide every individual the ability to control fresh air exposure and ensure good indoor air quality. However, determining how to improve air supply efficiency while avoiding a draft sensation is still a difficult question. This paper introduces a body movement-based personalized targeted air supply device. Two indices, size target value Ts and velocity target value Tr , are introduced to evaluate the degree to which the created flow field reaches the desired level. Additionally, the air supply effect of the device is compared with that of other devices. This research shows that the personalized targeted air supply device can successfully deliver air to the target area and improve air supply accessibility in the target area. The multinozzle coupling air supply mode produces a flow field air velocity of approximately 0.3 m/s, thus effectively avoiding a draft sensation. Compared with that of other personalized nozzles, the energy consumption is reduced significantly, by 88.2%, while the air supply accessibility can be increased by 48% with equivalent energy consumption.

On-site investigation of the concentration and size distribution characteristics of airborne fungi in a university library.

It is important to investigate fungal air quality in libraries because they represent a complex indoor environment. The aim of the study was to quantitatively investigate airborne fungal contamination levels based on field measurements in autumn and winter in four selected library rooms (compact stack, lending room, reading room, study room) in a university library building, as well as the effects of several factors on the culturability of airborne fungi. Airborne fungal levels varied by room, with the highest fungal levels in the reading room (634 ± 275 CFU/m3) and the lowest in the lending room (486 ± 177 CFU/m3). Airborne fungal concentrations were significantly different with seasonal variation (p < 0.05) for all rooms except for the reading room. The size distribution analysis showed that the most airborne fungi were 1.1-3.2 µm in size; based on the schematic diagram of the human respiratory system, more than 80% of airborne fungi could be deposited in the lower respiratory tract (0.65-4.7 µm). Indoor/outdoor airborne fungal concentration ratios were below 1.0 for all four rooms during autumn and winter, showing that outdoor fungi are the main source of indoor fungi. Pearson correlations showed that the fungal concentration was significantly positively correlated with both temperature (r = 0.531, p < 0.05) and relative humidity (r = 0.555, p < 0.05). Indoor temperature, indoor relative humidity and number of open windows significantly positively affected airborne fungal concentration in a multiple linear regression model (p < 0.05). This paper provides fundamental data on fungal contamination that can help experts in indoor air quality to develop guidelines for airborne fungi in libraries and create a safe environment for library patrons and staff.

A Pilot Study of RSK4 Expression in Patients with Human Non-Small Cell Lung Carcinoma.

BACKGROUND: Lung cancer represents the leading cause of cancer deaths worldwide, with non-small cell lung carcinoma (NSCLC) comprising the most common type of lung cancer. OBJECTIVE: The aim of this pilot study was to ascertain RSK4 expression at both the gene and protein level in normal and cancerous tissue of patients with NSCLC. METHODS: From January 2015 to December 2015, a total of forty patients diagnosed with NSCLC who underwent surgery were recruited into this study. All NSCLC diagnoses were confirmed by pathological examination. Normal and cancerous lung tissues were collected via surgical dissection. RSK4 gene and protein expression levels were ascertained using reverse transcription-polymerase chain reaction amplification and immunohistochemistry, respectively. Expression levels and patient pathological clinical parameters were compared by semi-quantitative method. RESULTS: Both RSK4 gene and protein expression levels were significantly reduced in patient cancerous tissue compared to their normal lung tissue (P<0.01). CONCLUSIONS: RSK4 expression is associated with clinical and pathological staging of NSCLC. Our preliminary data from this pilot study suggest that RSK4 constitutes a putative tumor suppressor gene for NSCLC. The relationship between RSK4 gene expression and NSCLC prognosis and clinical outcome needs to be further studied in a multi-center cohort study with a large patient sample.

Decitibine improve the efficiency of anti-PD-1 therapy via activating the response to IFN/PD-L1 signal of lung cancer cells.

IFN-γ-induced PD-L1 expression represents the existence of tumor-specific T cells, which predicts high-response rate to anti-PD-1/L1 therapy, but loss-of-function of IFN signals (e.g., JAK mutation) induces adaptive immune resistance in patients with low-response rate. Interferon regulatory factors (IRF) are frequently epigenetic silenced in carcinogenesis, while the role of methylation in anti-PD-1/L1 therapy remains unclear. We here investigated the methylation status of IFN-γ related genes IRF1/8 and IFN-α/ß-related genes IRF3/7 in lung cancer tissues and found that only highly methylated IRF1 and 7 negatively correlated to cd274 (coding PD-L1) expression, similar to JAK mutation. Interestingly, decitibine (DAC) as methylation inhibitor could hypomethylate IRF1/7 to restore PD-L1 level. Meanwhile, IRF7 enhanced constitutive PD-L1 expression, which was independent of IFN-γ though directly promote transcription of PD-L1, leading to abrogating cytotoxic T lymphocytes (CTLs) generation which could be restored by anti-PD-L1 antibody, or siRNA-IRF7. The supplement of DAC to anti-PD-1 therapy in vivo improve the efficiency of anti-tumor with less methylated IRF1/7, more interferon-related genes expression (e.g., CXCL9) and IFN-γ/CD8+ T-cells infiltrations, suggesting that additional treatment of DAC could rescue the ability to response to IFN in lung cancer patients with anti-PD-1/L1 therapy resistance.

The loss-of-function of DNA methyltransferase 1 by siRNA impairs the growth of non-small cell lung cancer with alleviated side effects via reactivation of RASSF1A and APC in vitro and vivo.

Hypermethylation of tumor suppressor genes (TSGs) promoters by DNA methyltransferase (DNMT) can be observed in almost all cancers which represent a hallmark of carcinogenesis, including lung cancer. DNMT inhibitors (e.g.5-Aza-CR/CdR) reactivate TSGs to exert anti-cancer activity and have been applied into the clinical. However, it is cytotoxic even at low concentrations, which might be not directly related to DNA methylation. We here investigated an alternative strategy in the lung cancer therapy and aimed to estimate and compare its efficiency and side effects of knockdown of DNMT1 in vitro and in vivo. Lung cancer tissues (n=20) showed enhanced expression of DNMT1 than corresponding non-neoplastic tissues. Similar results were found in lung cancer cell lines A549 and H538. The treatment of 5-Aza-CR or knockdown of DNMT1 in vitro could inhibit the expressions of DNMT1 but restore the TSGs expressions including the Ras association domain family 1A (RASSF1A) and the adenomatous polyposis coli (APC) via the demethylation of its promoter region, which results in the decreased proliferation, increased apoptosis and impaired ability of migration. Importantly, knockdown of DNMT1 by siRNA in vivo also effectively demethylated the RASSF1A and APC promoter, elevated their expressions and limited tumor growth, which functioned like 5-Aza-CR but with alleviated side effects, suggesting that knockdown of DNMT1 might be potential strategy for the treatment of lung cancer with better tolerability.

Hypermethylation of ATP-binding cassette B1 (ABCB1) multidrug resistance 1 (MDR1) is associated with cisplatin resistance in the A549 lung adenocarcinoma cell line.

Development of multiple drug resistance has been attributed to the overexpression of the ATP-binding cassette B1 (ABCB1) gene. In this study, the major purpose was to assess the expression and methylation levels of ABCB1 in human lung adenocarcinoma and to reveal the relationship between these processes and acquisition of cisplatin (DDP) resistance in the human cancer cell line A549. Methylation and expression levels of the ABCB1 gene ABCB1 in clinical human lung tissue were assessed using bisulphite sequencing, reverse transcription real-time PCR (RT2 -PCR) and Western blot methods. Cell viability, DDP resistance and apoptosis of A549 cells were evaluated using the Cell Counting Kit-8 and fluorescence-activated cell sorter analysis. Our results showed that the onset of resistance to the cisplatin analogue, DDP, was associated with hypermethylation of the ABCB1 gene. Expression of the ABCB1 gene was enhanced at both mRNA and protein levels. Treatment with 5-Aza-C contributed to the hypomethylation of the ABCB1 gene and decreased ABCB1 protein expression in A549 cells. In conclusion, this in vitro and human tissue study of lung adenocarcinoma cells demonstrated that hypermethylation of the ABCB1 gene correlated with increased gene expression and was associated with the acquisition of resistance to the cisplatin analogue, DDP in human lung adenocarcinoma cells. Taken together, our study highlighted the connection between increased ABCB1 methylation level and upregulated expression of the gene in lung cancer. Moreover, the abnormally high expression of ABCB1 in A549 cells contributed to the development of the DDP resistance.

Silencing DNA methyltransferase 1 (DNMT1) inhibits proliferation, metastasis and invasion in ESCC by suppressing methylation of RASSF1A and DAPK.

Our previous study showed DNMT1 is up-regulated in esophageal squamous cell carcinoma (ESCC), which is associated with methylation of tumor suppressors. In the current study, we investigate the role of DNMT1 in ESCC. We found silencing DNMT1 inhibited proliferation, metastasis and invasion of three different ESCC cells, K150, K410 and K450. We also found silencing DNMT1 induced G1 arrest and cell apoptosis in K150, K410 and K450 cells. In vivo study showed silencing DNMT1 suppressed tumor growth in nude mice. In addition, silencing DNMT1 increased expression of tumor suppressor genes, RASSF1A and DAPK, in ESCC cells and ESCC xenograft in nude mice. Moreover, silencing DNMT1 decreased methylation in promoter of RASSF1A and DAPK. In conclusion, our data demonstrated that silencing DNMT1 inhibits proliferation, metastasis and invasion in ESCC by suppressing methylation of RASSF1A and DAPK.

Promoter methylation status of tumor suppressor genes and inhibition of expression of DNA methyltransferase 1 in non-small cell lung cancer.

DNA methylation is an epigenetic DNA modification catalyzed by DNA methyltransferase 1 (DNMT1). The purpose of this study was to investigate DNMT1 gene and protein expression and the effects of methylation status on tumor suppressor genes in human non-small cell lung cancer (NSCLC) cell lines grown in vitro and in vivo Human lung adenocarcinoma cell lines, A549 and H838, were grown in vitro and inoculated subcutaneously into nude mice to form tumors and were then treated with the DNA methylation inhibitor, 5-aza-2'-deoxycytidine, with and without treatment with the benzamide histone deacetylase inhibitor, entinostat (MS-275). DNMT1 protein expression was quantified by Western blot. Promoter methylation status of tumor suppressor genes (RASSF1A, ASC, APC, MGMT, CDH13, DAPK, ECAD, P16, and GATA4) was evaluated by methylation-specific polymerase chain reaction. Methylation status of the tumor suppressor genes was regulated by the DNMT1 gene, with the decrease of DNMT1 expression following DNA methylation treatment. Demethylation of tumor suppressor genes (APC, ASC, and RASSF1A) restored tumor growth in nude mice. The results of this study support a role for methylation of DNA as a potential epigenetic clinical biomarker of prognosis or response to therapy and for DNMT1 as a potential therapeutic target in NSCLC.

Methylation of RASSF1A gene promoter and the correlation with DNMT1 expression that may contribute to esophageal squamous cell carcinoma.

BACKGROUND: Esophageal squamous cell carcinoma is one of the most common malignancies in the world. Studies have confirmed that there are many genes abnormally hypermethylated in esophageal squamous cell carcinoma. The objective is to detect methylation of the RASSF1A gene promoter and the expression of the DNA methyltransferase 1 (DNMT1) protein in esophageal cancer tissue and discuss their relationship with esophageal squamous cell carcinoma. METHODS: The CpG island methylation status of RASSF1A genes were analyzed in 100 cases of tumor specimens as well as their adjacent tissues which was used for methylation-specific polymerase chain reaction (MSP). The expression of DNMT1 protein was determined by immunohistochemistry. Difference between measurement data and categorical data was compared through analysis of t test and chi-square test. All the statistics were taken with a bilateral test. The difference was statistically significant (P < 0.05). RESULTS: The promoter methylation of the RASSF1A gene promoter has been detected in 45 out of 100 (45%) esophageal squamous carcinoma cases, while methylation of RASSF1A gene has been detected in 2 out of 100 adjacent normal tissues (2%). The RASSF1A gene promoter was highly methylated in cancer tissues, and there were significant differences between normal esophagus tissues and esophageal squamous carcinoma (P < 0.05). The expression of DNMT1 protein has been detected in 61 out of 100 (61%) esophageal squamous carcinoma cases, including 41 cases in the above 45 methylated samples of RASSF1A gene promoter, and none in adjacent tissues. DNMT1 proteins are highly expressed in cancer tissues, and there were significant differences (P < 0.05). In positive cases for methylation of RASSF1A, the DNMT1 protein had been detected in 41 out of 45 (91%), while in non-methylated cancer cases, 20 out of 55(36.3%), and the difference is significant (P < 0.05). CONCLUSIONS: Esophageal squamous carcinoma tumorigenesis may be related with hypermethylation of DNMT1 and RASSF1A promoter CpG island due to their high expression and also their hypermethylation.

Surgical treatment of an endobronchial lipoma obstructing the right upper bronchus: Imaging features with pathological correlation.

Endobronchial lipomas are rare benign unusual tumors of the respiratory tract. We describe a 65-year-old Chinese man with a history of cough due to an endobronchial tumor. The endobronchial biopsy was not excisional and was unable to evaluate the whole tumor. Then the mass was successfully resected via a right lateral thoracotomy. The histopathological diagnosis confirmed a benign lipoma arising from the membranous trachea. His CT features and fiberoptic bronchoscopic findings are shown along with the pathological results. In describing the management of this case, we stress that the clinical treatment of such tumors should be individualized according to the characteristics of each patient and mass.

[Experimental study of myocardial protective effect of cardiac arrest versus beating heart during open heart surgery].

OBJECTIVE: To investigate the myocardial protective effects of beating heart versus heart arrest in goats undergoing open heart surgery with cardiopulmonary bypass (CPB). METHODS: Eighteen healthy and homologous goats were randomly divided into three groups: groupI (n=6), with intermittent cold crystalloid cardioplegia; group II (n=6), with continuous warm blood cardioplegia; group III (n=6), with beating heart. Animals in group II and group III were operated with mild hypothermic CPB. The changes in malondialdehyde (MDA) in the myocardium of the right ventricles and atrial natriuretic peptide (ANP) in venous blood were measured respectively. The myocardial tissues were examined for ultrastructural changes. RESULTS: In group I, contents of MDA and ANP rose significantly during CPB, especially when blood was reperfused routinely. While in group II and group III, the levels were lower than those in group I at the same time points. There was no difference in the values between group II and group III. Ultrastructural changes were distinctly seen in group I, while they were mild in group II and group III. CONCLUSION: Continuous warm blood cardioplegia to keep the heart beating during operation can prevent ischemia-reperfusion injury and protect heart better.