Field Evaluation for Air-source Transcritical CO2 Heat Pump Water Heater with Optimal Pressure Control

Air-source transcritical CO2 heat pump water heater (ATHW) can supply hot water from 60 ? to 90 ? at high efficiency with environment-friendly refrigerant CO2 for commercial, residential and industrial applications. Several optimal discharge pressure correlations for transcritical CO2 heat pump have been proposed in the past few years, most of which are related to the ambient temperature, the evaporation temperature and the gas cooler outlet temperature. In an earlier study, the authors’ research group had presented a study on the dependency of the optimal discharge pressure on the ambient temperature and the hot water outlet temperature. In this study, a revised model for optimal discharge pressure is developed based on experimental results. In order to validate the optimal discharge pressure model developed, field tests are conducted to evaluate the performance of an air-source transcritical CO2 heat pump water heater in practical application. The system is comprised of a semi-hermetic reciprocating compressor, a counter-flow tube-in-tube gas cooler, a counter-flow internal heat exchanger, a fin-and-tube evaporator, and an electronic expansion valve (EEV) driven by electrically operated step motor. A Siemens SIMATIC S7-200 Programmable Logic Controller (PLC) was used to regulate the compressor discharge pressure by adjusting the EEV opening and the water flow rate by changing the frequency of the variable speed water pump. Field tests were conducted under three different operating scenarios: the nominal test condition, high water supply temperature condition and low ambient air temperature condition. The results show that the coefficient of performance (COP) can achieve 3.76 in the nominal test condition with 15? water inlet temperature and 80? hot water supply temperature. Even when the hot water temperature is higher than 90?, the COP remains at 3.21 with 20? dry-bulb temperature and 15? wet-bulb temperature. Under low ambient air temperature condition, the COP was 2.19 with the hot-water supply temperature of 60?. Comparison between the field test results and the model predictions show that the maximum relative error of discharge pressure control was 5.6% in the low temperature condition, while the maximum relative error of system COP was only 4.7%. With the reasonable agreement observed between the field test results and the model prediction. It is reasonable and effective to model the optimal discharge pressure as the function of the ambient temperature and the water outlet temperature

Renal collecting duct carcinoma with extensive coagulative necrosis mimicking anemic infarct: report of a case and the literature review

Collecting duct carcinoma (CDC) with a mass of coagulative necrosis is very rare. We report here a case of CDC with extensive geographic coagulative necrosis mimicking anemic infarct with tumor cells embedded around the necrotic foci in a 73-years-old man. Histopathological examination showed that tumor nests near the necrotic foci were arranged as angulated tubules, tubulopapillary and glandular structures. Neoplastic cells had moderate to abundant eosinophilic cytoplasm and large hyperchromatic nuclei with prominent nucleoli as Fuhrman nuclear grade 3 or 4. The tumor cells were positive for pan-Cytokeratin, Vimentin, E-cadherin, CD10, and CK7, confirming the diagnosis as CDC. The patient is still alive 6 months later from nephrectomy, a long time following up is needed to learn the prognosis. Conclusively, morphology from different portions of the lesion, immunohistochemical stain and the combination analysis of the radiological features is essential to make a precise pathological diagnosis of CDC. And CDC should also be distinguished from clear cell renal cell carcinoma, renal medullary carcinoma, urothelial carcinoma with glandular differentiation, renal neuroendocrine tumor, renal epithelioid angiomyolipoma, renal pigmented paraganglioma and renal mesenchymal chondrosarcoma etc. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/126427052597503

Vitamin D Deficiency Is Associated with Endoscopic Severity in Patients with Crohn’s Disease

Background and Aims. Vitamin D deficiency is common in patients with Crohn’s disease and is associated with disease activity. Relationship between vitamin D and endoscopic disease activity is unknown. The aim of the study is to determine the association between vitamin D status and endoscopic disease activity in CD patients. Methods. Consecutive hospitalized CD patients from 2014 to 2016 who received vitamin D assessment and colonoscopy were retrospectively evaluated. Clinical disease activity was assessed by Crohn’s disease activity index and C-reactive protein. Endoscopic activity was calculated using simple endoscopic score for Crohn’s disease. Results. Median serum 25OHD level of 131 patients was lower than healthy controls [21.1 nmol/L (11.8–32.3) versus 49.9 nmol/L (44.9–57.4), P=0.007]. 125 (95%) patients had vitamin D deficiency and the rest (5%) had vitamin D insufficiency. Serum 25OHD was inversely correlated with CRP (r=−0.308, P<0.001), CDAI (r=−0.582, P<0.001), SES-CD (r=−0.294, P=0.001), and endoscopic severity stratified by SES-CD (P=0.001). Conclusion. Vitamin D deficiency was prevalent among hospitalized CD patients. Vitamin D levels were inversely correlated with endoscopic disease activity. Vitamin D status could be a biomarker in assessing disease activity among hospitalized CD patients in addition to CDAI and CRP

PMNet: a multi-branch and multi-scale semantic segmentation approach to water extraction from high-resolution remote sensing images with edge-cloud computing

In the field of remote sensing image interpretation, automatically extracting water body information from high-resolution images is a key task. However, facing the complex multi-scale features in high-resolution remote sensing images, traditional methods and basic deep convolutional neural networks are difficult to effectively capture the global spatial relationship of the target objects, resulting in incomplete, rough shape and blurred edges of the extracted water body information. Meanwhile, massive image data processing usually leads to computational resource overload and inefficiency. Fortunately, the local data processing capability of edge computing combined with the powerful computational resources of cloud centres can provide timely and efficient computation and storage for high-resolution remote sensing image segmentation. In this regard, this paper proposes PMNet, a lightweight deep learning network for edge-cloud collaboration, which utilises a pipelined multi-step aggregation method to capture image information at different scales and understand the relationships between remote pixels through horizontal and vertical spatial dimensions. Also, it adopts a combination of multiple decoding branches in the decoding stage instead of the traditional single decoding branch. The accuracy of the results is improved while reducing the consumption of system resources. The model obtained F1-score of 90.22 and 88.57 on Landsat-8 and GID remote sensing image datasets with low model complexity, which is better than other semantic segmentation models, highlighting the potential of mobile edge computing in processing massive high-resolution remote sensing image data

Causal association of sarcopenia with hepatocellular carcinoma risk in European population: a Mendelian randomization study

BackgroundThe causal association of sarcopenia with the incidence risk of hepatocellular carcinoma (HCC) in the European population, and the potential mediating role of C-reactive protein (CRP), remains unclear. This study employed a bidirectional two-sample, two-step Mendelian randomization (MR) analysis to investigate the causality and identify the mediator.MethodsSummary statistics for HCC, CRP, and sarcopenia-related traits, including appendicular lean mass (ALM), hand grip strength (HGS), and walking pace (WP), were acquired from publicly available databases. We conducted bidirectional MR and Steiger tests of directionality to check the presence of reverse causality. Additionally, a two-step MR analysis was used to assess the mediating effect of CRP in the causality between sarcopenia and HCC. Tests for heterogeneity and horizontal pleiotropy were performed.ResultsAs ALM increases, the risk of HCC occurrence decreases [odds ratio (OR), 95% confidence interval (CI): 0.703, 0.524–0.943; P = 0.019]. And, genetically predicted low-HGS (OR, 95%CI: 2.287, 1.013–5.164; P = 0.047) was associated with an increased incidence risk of HCC, with no reverse causality. However, we found no evidence supporting a causality between WP and HCC. CRP was identified as the mediator of the causal effect of ALM and low-HGS on HCC, with corresponding mediating effects of 9.1% and 7.4%.ConclusionsThis MR study effectively demonstrates that lower ALM and low-HGS are linked to an elevated risk of HCC within the European population, and the causality was not bidirectional. Furthermore, CRP serves as a mediator in the associations. These findings may help mitigate HCC risk among individuals with sarcopenia

Design, synthesis and biological evaluation of a novel colchicine-magnolol hybrid for inhibiting the growth of Lewis lung carcinoma in Vitro and in Vivo

Colchicine is a bioactive alkaloid originally from Colchicum autumnale and possesses excellent antiproliferative activity. However, colchicine-associated severe toxicity, gastrointestinal side effects in particular, limits its further therapeutic use. In the current study, we thus designed and synthesized a novel hybrid (CMH) by splicing colchicine and magnolol, a multifunctional polyphenol showing favorable gastrointestinal protection. The antitumor activity of CMH in Lewis lung carcinoma (LLC) was then evaluated in vitro and in vivo. Biologically, CMH inhibited the growth of LLC cells with an IC50 of 0.26 μM, 100 times more potently than cisplatin (26.05 μM) did. Meanwhile, the cytotoxicity of CMH was 10-fold lower than that of colchicine in normal human lung cells (BEAS-2B). In C57BL/6 mice xenograft model, CMH (0.5 mg/kg) worked as efficacious as colchicine (0.5 mg/kg) to inhibit tumor growth and 2 times more potently than cisplatin (1 mg/kg). In terms of mortality, 7 out of 10 mice died in colchicine group (0.75 mg/kg), while no death was observed in groups receiving CMH or cisplatin at 0.75 mg/kg. Mechanistic studies using Western blot revealed that CMH dose-dependently suppressed the protein expression of phosphorylated ERK. Molecular docking analysis further indicated that CMH was well fitted in the colchicine binding site of tubulin and formed several hydrogen bonds with tubulin protein. These results enable our novel hybrid CMH as a potential antineoplastic agent with lower toxicity, and provide perquisites for further investigation to confirm the therapeutic potentiality of this novel hybrid

Numerical Study on Rotor Deformation of Multiphase Twin-Screw Pumps Under High Gas Volume Fraction Conditions

Multiphase pumping with twin-screw pumps is a relatively new technology that has been proven successful in a variety of field applications. It has three advantages such as less environment pollution, few separation equipments and more convenient operation than the conventional system. Despite many advantages of this technology, some problems have been encountered when operating under conditions with high gas volume fractions (GVF). While twin-screw multiphase pump is operating under high GVF conditions, the inner temperature of the pump increases obviously. The clearances between rotors change greatly and influence the volumetric efficiency of the twin-screw multiphase pumps. In some severe conditions, it may cause the pump damage. In this paper, the actual force and thermal boundary conditions are proposed through further investigations of pressure distributions and heat transfer. And then the screw rotor deformation and temperature field are calculated under different GVF conditions with ANSYS software. The results indicate that the main deformation of screw rotors is thermal deformation and the maximum radial deformation occurs on the top of the rotor in the discharge port. Through analyzing the influence of screw rotor deformation on the clearance, it can be realized that the greatest clearance changes are in the root of the rotor, followed by circumferential clearance, and there is no changes in flank clearance

Data and Appendix

The dats is used for the paper named "Spatial Interaction of Regional Economic Development and its Influencing Factors: Evidence from China ", and the appendix is the results not presented in the paper.</p

A Temporal and Spatial Data Redundancy Processing Algorithm for RFID Surveillance Data

The Radio Frequency Identification (RFID) data acquisition rate used for monitoring is so high that the RFID data stream contains a large amount of redundant data, which increases the system overhead. To balance the accuracy and real-time performance of monitoring, it is necessary to filter out redundant RFID data. We propose an algorithm called Time-Distance Bloom Filter (TDBF) that takes into account the read time and read distance of RFID tags, which greatly reduces data redundancy. In addition, we have proposed a measurement of the filter performance evaluation indicators. In experiments, we found that the performance score of the TDBF algorithm was 5.2, while the Time Bloom Filter (TBF) score was only 0.03, which indicates that the TDBF algorithm can achieve a lower false negative rate, lower false positive rate, and higher data compression rate. Furthermore, in a dynamic scenario, the TDBF algorithm can filter out valid data according to the actual scenario requirements

An adaptive simple model trust region algorithm based on new weak secant equations

In this work, we proposed a new trust region method for solving large-scale unconstrained optimization problems. The trust region subproblem with a simple form was constructed based on new weak secant equations, which utilized both gradient and function values and available information from the three most recent points. A modified Metropolis criterion was used to determine whether to accept the trial step, and an adaptive strategy was used to update the trust region radius. The global convergence and locally superlinearly convergence of the new algorithm were established under appropriate conditions. Numerical experiments showed that the proposed algorithm was effective