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Reducing electricity consumption is of great importance by improving the operation performance of the heating systems based on solar-assisted air source heat pumps for domestic heating. The set hot-water-supply temperature of the heating system affect both the system operation performance and the indoor thermal comfort condition. The effect of low temperature heating on the system operation performance is investigated to figure out the way to significantly save electricity. A single-family house is chosen as the reference building and the heating system is modelled and simulated under the weather conditions in the locations of London, Aughton and Aberdeen in the UK over a year. The set hot-water-supply temperatures are taken to be 40 oC, 45 oC, 50 oC and 55 oC. For the heating systems, with the decrease in set hot-water-supply temperature from 55 oC to 40 oC, the yearly seasonal performance factor increases by 16.7%, 19.1% and 15.4% in London, Aughton and Aberdeen, respectively. Consequently, the yearly total electricity consumption decreases by 19.1%, 14.9% and 13.3% in London, Aughton and Aberdeen, respectively. The results show that low temperature heating enables significant reduction in electricity consumption of such heating systems.

Global eutrophication and climate warming exacerbate production of cyanotoxins such as microcystins (MCs), presenting risks to human and animal health. Africa is a continent suffering from severe environmental crises, including MC intoxication, but with very limited understanding of the occurrence and extent of MCs. By analysing 90 publications from 1989 to 2019, we found that in various water bodies where MCs have been detected so far, the concentrations were 1.4–2803 times higher than the WHO provisional guideline for human lifetime exposure via drinking water (1 µg/L) in 12 of 15 African countries where data were available. MCs were relatively high in the Republic of South Africa (averaged 2803 μg/L) and Southern Africa as a whole (702 μg/L) when compared to other regions. Values were higher in reservoirs (958 μg/L) and lakes (159 μg/L) than in other water types, and much higher in temperate (1381 μg/L) than in arid (161 μg/L) and tropical (4 μg/L) zones. Highly significant positive relationships were found between MCs and planktonic chlorophyll a. Further assessment revealed high ecological risk for 14 of the 56 water bodies, with half used as human drinking water sources. Recognizing the extremely high MCs and exposure risk in Africa, we recommend routine monitoring and risk assessment of MCs be prioritized to ensure safe water use and sustainability in this region.

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This study addresses the optical design of LED edge-lit light guide plate (LGP) for front light unit panel of high illuminating contrast. Front light displays have excellent readability in outdoor environment with bright ambient light. A LED light guide is still required as an auxiliary lighting, referred to as a front light unit (FLU), in a dim environment. The ray tracing of the FLU light guide plate can be roughly classified into the noise rays refracted out of LGP directly and the image rays refracted downward to illuminate the reading media. Only the image rays is effective for FLU, and the noise ray will result in glare problems. This study defines the Effective Contrast Ratio (ECR) as the percentage of the image rays over the total rays within the ± 30° viewing angle. The layout of cylindrical microstructures are analyzed to determine a preferred configuration design from either concave or convex features deployed on the emitting surface or the bottom surface of LGP. Thought the ray tracing simulations of both the convex bottom and the concave bottom feature designs show excellent ECR over 90%, the concave design is preferred for better durability and assembly concerns at a cost of lower illuminating efficiency. The optimum parameters of the truncated cone microfeature with maximum ECR are identified as the base diameter of 70 (μm), the aspect ratio of 0.46, and the feature sidewall angle of 78° using a sequential optimization of Kriging Surrogate. A preliminary prototype of the LGP has been fabricated using Polydimethylsiloxane (PDMS) molding process from a SU8 master. A qualitative comparison of the photographic pictures of a sample text demonstrates the excellent transparency and uniform illumination of the LGP with the proposed feature design.

To investigate the role of miR-27b in sheep skeletal muscle development, here we first cloned the sequence of sheep pre-miR-27b, then further investigated its expression pattern in sheep skeletal muscle in vivo, the relationship of miR-27b expression and sheep skeletal muscle satellite cell proliferation and differentiation in vitro, and then finally confirmed its target gene during this development process. MiR-27b sequence, especially its mature sequence, was conservative among different species. MiR-27b highly expressed in sheep skeletal muscle than other tissues. In skeletal muscle of Suffolk and Bashbay sheep, miR-27b was upregulated during foetal period and downregulated during postnatal period significantly (P

To achieve the goal set for net-zero emissions of greenhouse gases in the UK by 2050, the domestic heating must be decarbonised. Solar assisted air source heat pumps, integrating solar collector, thermal energy storage tank and heat pump, offers a promising alternative application under the UK weather conditions. Literature review shows that investigations of solar assisted air source heat pumps in the regions like the UK are still insufficient. The serial, parallel and dual-source indirect expansion solar assisted air source heat pumps are modelled and simulated under the weather conditions in London using TRNSYS to investigate the operation performance over a typical year. These three heat pumps are applied to provide space heating and hot water of 300 L per day for a typical single-family house. The simulation results show comparisons of the three systems. The serial type heat pump shows the highest seasonal performance factor of 5.5, but requiring the largest sizes of the solar collector and thermal energy storage tank. The dual-source and parallel type heat pumps show slightly lower seasonal performance factors of 4.4 and 4.5, respectively, requiring smaller sizes of solar collector and thermal energy storage tank. Furthermore, the results show that the air source part contributes to an important proportion of the heat provision and stable operation of the systems. The yearly seasonal performance factor higher than 4.4 achievable by the three heat pumps suggests that they are potentially applied in the regions with relatively lower solar irradiance. The economic analyses indicate that the parallel and dual-source type heat pumps provide good alternatives to replacing the gas-boiler heating system.

This study proposes the novel idea of implementing a decision support system (DSS) based on both the prevalent MEAN architecture and the R statistical language platform. A ‘MEAN+R’ framework is defined, and the effectiveness of this framework is verified by taking it as the basis for the implementation of a real user-side, web-based, multi-participant DSS supporting a group decision-making process of quasi-senior people, pertaining to the selection of the best and commonly-agreed senior center for co-living after retirement. The ‘model base’ of the DSS is a recent MADM model evaluating the criteria-wise source opinions of the decision makers (DMs) toward alternatives in terms of intuitionistic fuzzy numbers (IFNs), but within the model the original multi-objective decision-making (MODM) phase to determine whether the criteria weight vector (CWV) has been replaced with another well-accepted MADM model, which is the AHP. This ensures not only unified grounds for modelling, but also a coherent implementation basis for the MADM model in R. The outside Node.js programs access the ‘data base’ of the DSS managed using MongoDB and will invoke the R-written ‘model base’ codes while necessary. Then, the R program also interacts with the ‘data base’ to exchange the information relevant to the decision from/to users. An illustrative numerical group decision example supported by this DSS is provided, and an efficiency analysis is made by listing the time spent on both data and model bases separately and clearly, while excluding the other processes of the DSS. A key finding is that the computational time can be controlled when incorporating the vector-based R platform, i.e., it leaps forward to the next level only when the size of the problem increases to a certain extent. Finally, since the realized DSS is intended to face end users of the healthcare system (rather than the business-oriented service providers, e.g., hospitals, physicians, nurses, etc.), it may provide some supplement to healthcare decision support (rather than solving other types of problem, such as clinical decisions).

Solar assisted air source heat pump shows great potential as a promising energy-saving heating technology, which integrates solar collector and air source heat pump. It is widely considered for supplying hot water, space heating and/or space cooling in the domestic sector. The performance of solar assisted air source heat pumps can be evaluated in system level by parameters such as coefficient of performance, seasonal performance factor, energy consumption, solar fraction as well as initial and operating costs, and in component level by parameters such as efficiencies of solar collection and thermal energy storage. Their performances are affected by many factors such as system configuration, components size, working fluid, working conditions and weather conditions. This paper presents a comprehensive review on the recent advances in solar assisted air source heat pump for the domestic sector in terms of system configuration, solar collectors, thermal energy storage, defrosting method and the perspective areas of further investigations. The results of this review confirm that research is still required to improve the performance of such a combined system and reduce initial cost compared with existing heating systems based on hydrocarbon combustion. The information presented in this paper is beneficial to the researchers, small and medium-sized enterprises suppling renewable energy system technologies, heating engineers and service workers, energy policy and decision makers, environmental activists and communities.

Figure S1. HBV breakpoint detection workflow from sequencing reads in FuseSV. Figure S2. HBV sub-genotype tree in host by VCS analysis. Figure S3. Constructing HBV genomes in tumors by VCS analysis. Figure S4. Comparison of genome-wide somatic SNVs among the six tumor specimens. Figure S5. Comparison of genome-wide copy number in six tumor specimens. Figure S6. EXT1 expression in hepatic or HCC cell lines by western blot. Figure S7. EXT1 affects HCC growth in vitro. Figure S8. EXT1 does not affect HCC cell migration in vitro. Table S1. Clinicopathologic features of the HBV patient with multiple HCC. Table S2. Sequencing data summary and HBV genome details of ten specimens. Table S3. VCS data summary and constructed HBV genome details of 264 single cells. Table S4. Alterations on HBV_B2 genome in ten specimens. Table S5. Homologous sequences at the junction sites of minor viral integration and HBV rearrangement cases. Table S6. Copy number alterations of six tumor specimens. Table S7. Somatic structure variations of six tumor specimens. (PDF 5584 kb)

Cu2Y2O5 thin films were deposited on non-alkali glass substrates by RF magnetron sputtering. Its crystal structure, microstructure, optical property, mechanical property, and antibacterial activity were investigated by grazing-incidence X-ray diffraction, transmittance spectra, nanoindenter, and antibiotics test, respectively. A single-phase of Cu2Y2O5 was obtained while annealing at 700 °C in air and its optical transparency was >80% in the visible region. The hardness and elastic modulus of the film were 6.7 GPa and 82 GPa, respectively. Antibiotics testing result revealed that Cu2Y2O5 surface had a superior antibacterial performance even at a dark environment. Therefore, Cu2Y2O5 is a promising novel transparent antibacterial hard coating material.

The paper reports numerical and experimental investigation of a compound parabolic concentrator-capillary tube solar collector (CPC-CSC). The capillary tube having an outer diameter 4 mm is used as the absorber, which reduces the size of the solar collector and achieves a concentration ratio of 4.22 in comparison with the same thickness 75 mm of a flat-plate solar collector. The horizontal CPCs separate the air layer into smaller cells, resulting in decrease in heat loss through the air layer. Details of the design and work principle of the new collector are described. Both experimental and numerical studies were carried out for the purpose of operating characteristics and thermal performance of the solar collector. The effect of solar irradiation intensity and inlet water temperature were tested based on the standard of GB/T 4271-2007. A three-dimensional model of the collector is developed and its performance is numerically simulated using FLUENT. The influence of solar irradiation intensity, velocity of ambient air, glass thickness, insulation thickness, inclination angle, mass flow rate and inlet temperature of water are analyzed. The results of numerical were verified by experimental data and the maximum deviation is found to be 15%. The numerical results suggest that: 1) the main heat losses of the CPC-CSC is due to the heat leakage through the air layer between glass cover and CPC; 2) the collector efficiency decreases as the convective heat transfer of the air layer increases; 3) when the solar irradiation intensity rises, the surface temperature of collector tubes increases, enhancing air layer convection and thus reducing collector efficiency; 4) with the increase in mass flow rate of water in the pipe, the heat absorption of water in the pipe increases and thus the collector efficiency increases and 5) the velocity of ambient air, glass thickness, insulation thickness, and inclination angle have little effects on the performance of the solar collector.

Since the global financial crisis in 2008 had caused the global economic depression, the public were commonly losing confidence in monetary system and international fund associations. Thus, the concept of untraditional currency exchange was developed. Nakamoto (2008) designed bitcoin, a decentralized digital currency which is launched and traded on the Internet. Bitcoin is being gradually accepted by the public, which is attributed to the feature of decentralization and anonymity. The exchange rate of bitcoin reached to the peak price at $4425.30 USD on August 16th, 2017. However, due to the concern of the security challenges such as being stolen, the public lost the confidence of bitcoin and had a conservative attitude toward bitcoin. It also shows that the relevant technical application and transaction model of bitcoin still need to be improved. This research attempted to investigate the key factors that prompt users to adopt bitcoin through a two-phase analysis. First, the literature and main social media data were reviewed to list out the key phrases. Second, OpView Social Listening Platform was adopted to collect data, and social network content mining method and the key phrases mentioned above were used to analyze the data from social media forum open to Taiwan. This explored the users' opinions and positive and negative emotional attitude about the latest bitcoin breaking news. This research is expected to provide references for the users when considering adopting bitcoin. It is expected to compare and analyze the data from other countries in the future.

This paper studies the temperature field variation of the chain link as well as the stress and deformation distribution of the pin which works in hot forging and stamping production line with heat recovery function. The approach is to build the model of the chain link with Pro/Engineer and apply it to the simulation with Pro/Mechanica. To be specific, it is to stimulate the thermal conduction of the chain link and the stress state of the pin under high temperature with Pro/Mechanica-Thermal and Pro/Mechanica-Structure module, respectively. The results are the temperature filed nephogram of the chain link as well as the stress and deformation nephogram of the pin. The simulation shows that:1) the temperature reaches 420°C at the contacts of the outer and inner plates at 600s, 2) the maximum stress of the pin is 112Mpa at the ends where the pin meets the outer and inner plates,3) the pins max deformation is 0.0159mm at the middle of the pin. Comparing the simulation to the actual temperature at the contacts of the outer and inner plates,which is measured ten times in advance with average of 439°C ,the simulation is favorable. According to the results above, graphite lubrication should be chosen for the chain and the pin can work properly with deformation rate of 0.795. By this way of simulating with Pro/Mechanica, complicated calculations and repeated tests can be reduced largely, meanwhile, useful parameters and mathematical model can also be provided for manufacturing and process control.

As a largest wetland of north China, Lake Baiyangdian is of great significance to the regional climate and ecological environment. However, as the impact of human activities and dry climate, the lakes water pollution and eutrophication is becoming worsen and worsen. We analyzed the hydro-chemical composition and used five indexes [Chla, TN, TP, CODMn and S to assessment the hydrochemistry characteristics and eutrophication level of Lake Baiyangdian. The results show that the type of water was CIINa. Using principal component analysis, we find that TN and TP are the two main factor of the lakes pollution. The diatom assemblage shows that the main diatom species are Cymbella microcephala and Synedra nana and the contents of Cyclotella atomus and C.meneghiniana have reached a relative level which is indicating Lake Baiyangdian has been in a state of eutrophication.

Soil salinity can limit plant growth and productivity. The cultivation of tolerant varieties is convenient and cost-effective for making good use of the saline soils. The sweet sorghum plant has a high tolerance for saline alkaline soils. The KF1210-3 and KF1210-4 early-maturity mutants of sweet sorghum were obtained via carbon ion irradiation. The study assesses the productivity of three sweet sorghum cultivars (KF1210-3, KF1210-4, and KFJT-CK) which were grown in intermediate (4.6 dS m−1) and high (11.9 dS m−1) soil salinity. The sweet sorghum grown in the soil salinity of 4.6 dS m−1 produced 50.00–57.30 % greater fresh weight than that in the soil salinity of 11.9 dS m−1, while the difference was not as obvious among the dry biomass of the three sweet sorghum cultivars. Moreover, the Brix degree of the sweet sorghum grown in the soil salinity of 11.9 dS m−1 was greater than that grown in the soil salinity of 4.6 dS m−1. The heavy ion irradiation experiment is of great significance in screening plant mutants, improving environmental conditions, and assessing the productivity. This process, in turn, aids in the understanding of the effects of the biochemical and physiological mechanisms of salt stress.

To reveal the potential genetic mechanisms of indole-3-acetic acid (IAA) that regulate Chinese fir wood formation, cloned the differentially expressed genes via suppress subtractive hybridization (SSH) using the truncated stems treated by 0 and 3 mg IAA/g lanolin as the driver and tester, respectively. A total of 332 unigenes that were involved in cell organization and biosynthesis, developmental processes control, electron transport, stress response, and signal transduction. To further test the results from SSH, we selected those unigenes, whose putative encoding proteins showed significantly homologous with HIRA, PGY1, SMP1, TCT, TRN2, and ARF4, and analyzed their expressed specificity in the wood formative tissues and their response to the secondary developmental changes of vascular cambium stimulated by 0, 1, and 3 mg.IAA/g.lanolin treatment. The results showed that ClHIRA, ClPGY1, and ClARF4, which were specifically expressed in the adaxial zone of stem, were positively response to the activities of cell division and tracheid differentiation stimulated by exogenous IAA treatment. However, ClSMP1, ClTCTP1, and ClTRN2, which were mainly expressed in the abaxial zones of stems, showed negative correlation with the treated levels of exogenous IAA and activities of vascular cambium secondary development at the transcriptional level. This result showed that the differential response of developmental regulatory genes located in different vascular tissues to the level changes of edogenous IAA in stems is likely to be an important molecular mechanism of auxin regulating wood formation.

We theoretically study the impact of changes in surroundings on the electron ground-state effective $g$ factor in defect-free GaAs/AlGaAs nanodisks. To perform the study, we formulate and deploy a computational efficient full three-dimensional model to describe the effective $g$-factor tensor in semiconductor nano-objects of complex geometry and material content. This model is based on an effective $2\ifmmode\times\else\texttimes\fi{}2$ conduction-band Hamiltonian which includes the Rashba and Dresselhaus spin-orbit couplings. The description is suited to clarify the important question of the controllability of the electron effective $g$ factor in semiconductor nano-objects. The results of this theoretical study suggest that in the defect-free GaAs/AlGaAs nanodisks, the effective $g$ factor can be tuned within a wide range by proper design of the nanodisk environment. The $zz$ components of the electron effective $g$-factor tensor obtained in our simulation are in good agreement with some recent experimental observations.

The volatilization behavior of Seleenium in coal / coal char was studied by determining the concentration of Se with AFS at H2O(Ar) atmosphere in high-temperature tube furnace. The inhibition effects on the volatilization of Se with calcium-based material (CaO) and nano materials Fe3O4as absorbents were studied during coal gasification. The results show that the volatilization rates of Se, rising with the temperature of gasification, can be effectively controlled with the absorbent of CaO. Because CaO can reacts with Se produce CaSeO4, a more stable compoud. Nano-Fe3O4can enhance the ability of CaO to inhibit the volatilization of selenium, it is because not only can promote more CaSeO4, while also reducing the possibility of its decomposition.

Traumatic posterior atlantoaxial dislocation without related fractures of the odontoid process and anterior arch of the atlas is exceedingly rare, with only ten published cases reported so far in English literature. We report on a 44-year-old man with post-traumatic posterior displacement of the atlas with respect to the axis without any associated fractures and neurological deficit caused by a crush injury in earthquake. Radiographs, computed tomography and magnetic resonance imaging revealed posterior displacement of the atlas with the odontoid peg lying anterior and to the right of the anterior arch of the atlas. Partial odontoidectomy and posterior fixation with bone graft were performed in one-stage procedure after several unsuccessful attempts of closed reduction. The patient did not have neurological deterioration after operation.

Expansins are unique plant cell wall proteins that possess the ability to induce immediately cell wall extension in vitro and cell expansion in vivo. To investigate the biological functions of expansins that are abundant in wood-forming tissues, we cloned two expansin genes from the differentiating xylem of Chinese fir (Cunninghamia lanceolata (Lamb.) Hook). Phylogenetic reconstruction indicated that they belong to α-expansin (EXPA), named ClEXPA1 and ClEXPA2. Expression pattern analysis demonstrated that they are preferentially expressed in the cambium region. Overexpression of ClEXPA1 and ClEXPA2 in tobacco plants yielded pleiotropic phenotypes of plant height, stem diameter, leaf number and seed pod. The height and diameter growth of the 35S(pro) :ClEXPA1 and 35S(pro) :ClEXPA2 transgenic plants were increased drastically, exhibiting an enlargement of pith parenchyma cell size. Isolated cell walls of ClEXPA1 and ClEXPA2 overexpressors contained 30%-50% higher cellulose contents than the wild type, accompanied by a thickening of the cell walls in the xylem region. Both ClEXPA1 and ClEXPA2 are involved in plant growth and development, with a partially functional overlap. Expansins are not only able to induce cell expansion in different tissues/organs in vivo, but they also can act as a potential activator during secondary wall formation by directly or indirectly affecting cellulose metabolism, probably in a cell type-dependent manner.

Ultra-performance liquid chromatography (UPLC), as a development of the chromatographic technique, was used in the quality control of Panax ginseng C.A. Mey. In the study, the UPLC methods were transferred from conventional high-performance liquid chromatography (HPLC) methods according to chromatographic equations. The results demonstrated that UPLC analysis methods could be transferred from HPLC without loss of efficiency. Compared with conventional HPLC, UPLC made a surprising 10-fold increase in speed and 20-fold decrease in solvent consumption. The study indicated UPLC as a suitable alternative to HPLC and can be reliably applied to quality control of traditional Chinese medicines.