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Background: Antifungal Peptides (AFP) have been found to be effective against many fungal infections. Objective: However, it is difficult to identify AFP. Therefore, it is great practical significance to identify AFP via machine learning methods (with sequence information). Method: In this study, a Multi-Kernel Support Vector Machine (MKSVM) with Hilbert-Schmidt Independence Criterion (HSIC) is proposed. Proteins are encoded with five types of features (188-bit, AAC, ASDC, CKSAAP, DPC), and then construct kernels using Gaussian kernel function. HSIC are used to combine kernels and multi-kernel SVM model is built. Results: Our model performed well on three AFPs datasets and the performance is better than or comparable to other state-of-art predictive models. Conclusion: Our method will be a useful tool for identifying antifungal peptides.

Functional small-diameter tissue-engineered blood vessels (TEBVs) have been developed in silico using biodegradable polymeric scaffolds under pulsatile perfusion. Accurate simulation of physiological mechanical stimulations in vitro is a crucial factor in vascular engineering. However, little is known about the patterns of mechanical stimulation on silicone tubes. This study aimed to determine the optimal mechanical conditions required for inducing circumferential deformations in silicone tubes during in vitro vascular development under pulsatile perfusion. For this purpose, we established a data acquisition (DAQ) system with a laser micrometer and pressure transducers to evaluate changes in the diameter of silicone tubes in response to pulsatile flow and validated the results on cultured TEBVs. The established DAQ system showed satisfactory reproducibility for measuring diameter variation in the in silico model. Furthermore, the hardness and thickness of the silicone tubes affected the mechanical conditioning in the three-dimensional culture system under different working pressures, frequencies, and circumferential deformations. We demonstrated a simple and reliable approach to quantify the circumferential strain and deformations to ensure optimal mechanical stimulation of the cultured TEBVs under pulsatile perfusion. Based on the results, we were able to dynamically culture dense cellularized small-diameter TEBVs. This study highlights the importance of mechanical stimulation in vascular tissue engineering. Impact statement This study demonstrated a direct and noncontact data acquisition system for quantifying the strain on the supporting silicone medium during three-dimensional tissue-engineered blood vessel culture, which can help optimize the mechanical parameters for vascular tissue engineering.

The electrospray thruster relies on a large number of emission sites that simultaneously emit ions or charged droplets to generate thrust. The operation uniformity of the emission sites is of great significance to ensure the stable work of the thruster and improve its thrust level. However, there was little in-depth study of it before, especially of its influence on the thruster's characteristics. To this end, four porous electrospray thrusters with different degrees of non-uniform operation of emission sites were adopted, and their emission site distribution characteristics, volt-ampere characteristics, and current fluctuation characteristics were investigated. Emission site distribution of all thrusters showed a certain degree of unevenness. On their emission surfaces, there were some dark zones where few emission sites located on, highlight zones where emission sites were too concentrated, and intermediate zones where emission sites repeatedly appeared and disappeared. The appearance of a dark zone could cause a decrease in the growth rate of emitted current with voltage, and electric sparks that happened in the highlight zones could directly interrupt the operation of thrusters and suppress the increase of thrusters' thrust level. A periodic fluctuation, which should be caused by the flow rate difference between emission sites, emerged on the plume current of almost all thrusters. Various experimental results indicated that part of the liquid in high-flow-rate areas spread to low-flow-rate areas while the current fluctuated periodically. It could effectively reduce negative effects caused by the non-uniform operation of emission sites. The flow resistance of one of the four thrusters was greatly reduced. As a result, the operation uniformity of emission sites was greatly improved, but the overflow problem in high-flow-rate areas was exacerbated.

Heat flux is important for studying interactions between atmosphere and lake. The heat exchange between air-water interfaces is one of the important ways to govern the temperature of the water surface. Heat exchange between the air-water interfaces and the surrounding environment is completed by solar radiation, conduction, and evaporation, and all these processes mainly occur at the air-water interface. Hulun Lake was the biggest lake which is also an important link and an indispensable part of the water cycle in Northeast China. This study mapped surface energy budget to better understand spatial and temporal variations in Hulun Lake in China from 2001 to 2018. Descriptive statistics were computed to build a historical time series of mean monthly heat flux at daytime and nighttime from June to September during 2001–2018. Remote sensing estimation methods we used was suitable for Hulun Lake (R2 = 0.81). At month scale, shortwave radiation and latent heat flux were decrease from June to September. However, the maximum sensible heat flux appeared in September. Net longwave radiation was the largest in August. The effective heat budget showed that Hulun Lake gained heat in the frost-free season with highest value in June (686.31 W/m2), and then steadily decreased to September (439.76 W/m2). At annual scale, net longwave radiation, sensible heat flux and latent heat flux all show significant growth trend from 2001 to 2018 (P < 0.01). Wind speed had the well correlation on sensible heat flux and latent heat flux. Water surface temperature showed the highest coefficient in sensitivity analysis.

Understanding the spatial patterns of land-use and land-cover (LULC) and their driving forces in transnational areas is important for the sustainable development of these regions. However, the spatial patterns of LULC and their driving forces across multiple scales are poorly understood in transnational areas. In this study, we analyzed the spatial patterns of LULC and driving forces in the transnational area of Tumen River (TATR) in 2016 across two scales: the entire region and the sub-regions of China, the Democratic People’s Republic of Korea (DPRK), and Russia. Results showed that the LULC was dominated by broadleaf forest and dry farmland in the TATR in 2016, which accounted for 66.86% and 13.60% of the entire region, respectively. Meanwhile, the LULC in the three sub-regions exhibited noticeable differences. In the Chinese and the DPRK’s sub-regions, the area of broadleaf forest was greater than those for the other LULC types, while the Russian sub-region was dominated by broadleaf forest and grassland. The spatial patterns of LULC were mainly influenced by topography, climate, soil properties, and human activities. In addition, the driving forces of the spatial patterns of LULC in the TATR had an obvious scaling effect. Therefore, we suggest that effective policies and regulations with cooperation among China, the DPRK, and Russia are needed to plan the spatial patterns of LULC and improve the sustainable development of the TATR.

A poly(2-hydroxyethyl methacrylate) (pHEMA) hydrogel film was prepared by bulk polymerization. Then, it was surface modified by perfluorooctanoyl chloride to improve the anti-biofouling properties. Attenuated total reflectance-Fourier transform infrared (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDXS), and atomic force microscopy (AFM) analyses demonstrated that the uniform dense fluorinated layer had been successfully grafted onto pHEMA. The water contact angle (WCA) of the modified pHEMA film increased to 135°, while the surface energy decreased to 13.32 mN/m. The protein and bacterial adhesion properties of the modified pHEMA were decreased significantly. The in vitro cytotoxicity showed that the modified pHEMA was noncytotoxic. Thus, the fluorinated modification on the material surface was a convenient and effective method to establish a hydrophobic and anti-biofouling surface.

We consider an interval scheduling problem where n jobs are required to be carried out by m nonidentical machines in an offline-scheduling way. Each job has a starting time, a finishing time and a number of processing units. Every machine has different number of processing units to carry out jobs. A machine can process only one job at a time without interrupted on the condition that the number of its units must satisfy job’s requirement. Further more, all units in one machine consume energy if the machine is powered up. Within this setting, one is asked to find a proper schedule of machines so that the total number of working units is as less as possible. For this interval scheduling problem, we first discuss an exact method based on integer programming which can be solved by branch-and-bound algorithm. Then, we propose two approximated methods named GreedyBS and GreedyMR using greedy strategy. GreedyBS is proved to be a 2.1343-approximated algorithm. All proposed algorithms are tested on a large set of randomly generated instances. It turns out that GreedyBS requires less total units of machines under time constrain when comparing with GreedyMR and exact methods in most cases, while GreedyMR costs the minimum time. Several parameters of GreedyBS and GreedyMR were also evaluated to improve the performances of these two algorithms.

Mobile crowdsensing is a crowdsourcing-based paradigm, where the platform executes the sensing requests with the help of many common peoples' handheld devices (typically smartphones). In this paper, we mainly address the dynamic sensing request admission and smartphone scheduling problem to maximize the long-term profit, taking into account the competitive interaction procedure between the platform and smartphones, the queue backlog, and the location of sensing requests and smartphones. First, formulate this problem as a discrete time model and the interaction procedure between the platform and smartphones as a Stackelberg game. Then, we introduce the Lyapunov optimization technique and design a Stackelberg game based dynamic Admission and Scheduling algorithm(SAS). In SAS, all control decisions are made only based on the currently available information and none of the stakeholders, including the platform and smartphones, can improve his utility by unilaterally changing its current strategy. Next, we design an online Cooperative dynamic Admission and Scheduling algorithm(CAS) for the situation where the platform and smartphones work in a cooperative way. Theoretical analysis shows that under any control parameter V > 0, both SAS and CAS algorithm can achieve O(1/V)-optimal average profit while the sensing request backlog is bounded by O(V). The extensive numerical results based on both synthetic and real trace demonstrate the Stackelberg equilibrium of the SAS. The CAS always outperforms SAS, and in some certain situations, the profit of SAS is very close to that of the CAS.

Habitat quality is a key indicator for assessing the biodiversity-maintenance functions of ecosystem services. The issue of habitat quality changes in semi-arid and arid areas has been becoming serious, but there are few deep investigations of habitat quality in these regions, such as studies of the temporal and spatial changes of habitat quality and its driving forces. This study focuses on the agro-pastoral ecotone of northern Shaanxi with vulnerable biodiversity. By using the Fragstats software, the InVEST model, and the Geo-detector model, we analyzed land-use data collected from 1990, 2000, 2010, and 2020, and we explored the landscape pattern index, the spatial and temporal variation of habitat quality, and the influence of its drivers. GDP, population density, precipitation, temperature, land use, NDVI, elevation, and slope were detected by Geo-detector. The research results show that: (1) Arable land and grassland were the dominant land types from 1990 to 2020, and there was significant mutual circulation between arable land and grassland. Forest area increased by 24%. Many other land-use types were transformed into construction land, and construction land increased by 727% compared with the base period. (2) Landscape heterogeneity increased in the study region, shown by the fractured structure of the overall landscape and by the aggravated human disturbance of the landscape. (3) Average habitat quality underwent a trend of oscillation. Regarding spatial distribution, habitat quality was higher in the east than in the west. (4) The influencing factors of habitat quality monitored by Geo-detectors show that the driving force of land use on habitat quality was the strongest, followed by precipitation and vegetation coverage. Elevation, slope, GDP, and population density had the least influence on habitat quality. The bi-factor interaction enhanced habitat quality to different levels. This study is critical to the conservation of biodiversity and to ecological civilization construction in arid and semi-arid regions.

Poly(zwitterions) polymer brushes were fabricated by surface-initiated atom transfer radical polymerization (SI-ATRP) on PVA substrate. The results of XPS and FTIR proved the successful graft of CBMA and SBMA to PVA. The surface of the PVA films would be rougher after the functionalization. Its hydrophilicity increased dramatically and the water contact angle decreased from 45.2° to 7.2°. The visible light transmittance was above 88%. Mechanical properties decreased slightly after grafting, the tensile strength and tensile strain at break were in 1.23-1.85 MPa and 361.7-471.1%, respectively. The anti-protein adsorption performance of the modified PVA film was significantly enhanced and the lowest adsorption amount was up to 2.25 μg/cm

Background As of September 17, 2021, coronavirus disease 2019 (COVID-19) has infected more than 226 million people in a worldwide pandemic, with conservative estimates suggesting that there are more than 204 million convalescent patients with COVID-19. Previous studies have indicated that patients in the recovery phase exhibit decreased function of multiple organs. In China, traditional Chinese medicine (TCM) treatment is recommended in the rehabilitation period of COVID-19; however, the safety and efficacy of such treatment remain to be confirmed. Aim of study The present study aimed to evaluate the efficacy and safety of Bufei Huoxue (BFHX) in restoring the functional status and exercise tolerance of patients recovering from COVID-19. Methods A total of 131 patients in the rehabilitation period of COVID-19 infection were randomly divided into a Bufei Huoxue (BFHX) group (n = 66) and a placebo group (n = 65). BFHX or placebo was given orally three times a day (1.4 g/dose) for 90 days. The primary outcomes was to evaluate improvements in exercise tolerance and imaging manifestations on chest computed tomography (CT). Results After the exclusion of two patients who withdrew prior to receiving any medications, 129 patients were recruited, including 64 patients in the BFHX group and 65 patients in the placebo group. After 3 months of treatment, the BFHX group exhibited greater attenuation of pneumonia lesions on chest CT than the placebo group (P, Graphical abstract Image 1

Design of artificial corneal scaffolds substitute is crucial for replacement of impaired cornea. In this paper, porous polyvinyl alcohol/silk fibroin/nano-hydroxyapatite (PVA/SF/n-HA) composite hydrogel was prepared via the genipin (GP) cross-linking, the pore diameter of the hydrogel ranged from 8.138 nm and 90.269 nm, and the physical and physiological function of hydrogel were investigated. The resulting hydrogel exhibited favourable physical properties. With the GP content increasing, the structural regularity of PVA/SF/n-HA composite hydrogel was enhanced and the thermal stability was improved. The moisture content was slightly decreased and generally maintained at approximately 70%. The tensile strength was heightened up to 0.64 MPa, while the breaking elongation was decreased slightly. Moreover, the biofunction was investigated. The

Non-coding RNAs (ncRNAs) are a type of RNA which are not used to encode protein sequences. Emerging evidence shows that lots of ncRNAs may participate in many biological processes and must be widely involved in many types of cancers. Therefore,understanding their functionality is of great importance. Similar to proteins,various functions of ncRNAs relies on their subcellular localizations. Traditional high-throughput methods in wet-lab to identify subcellular localization is time-consuming and costly. In this paper,we propose a novel computational method based on multi-kernel learning to identify multi-label ncRNA subcellular localizations,via graph regularized k-local hyperplane distance nearest neighbor algorithm. First,we construct six types of sequence-based feature descriptors and select important feature vectors. Then,we build a multi-kernel learning model with Hilbert-Schmidt independence criterion (HSIC) to obtain optimal weights for vairous features. Furthermore,we propose the graph regularized k -local hyperplane distance nearest neighbor algorithm (GHKNN) as a binary classification model for detecting one kind of non-coding RNA subcellular localization. Finally,we apply One-vs-Rest strategy to decompose multi-label problem of non-coding RNA subcellular localizations. Our method achieves excellent performance on three ncRNA datasets and three human ncRNA datasets. We evaluate our predictor on a novel multi-label benchmark set,and out-performs other outstanding machine learning methods.

Cloud computing provides users a shared pool of configurable computing resources. In this paper, a cloud computing system is regarded as a queuing system, where users arrive according to a stochastic process and request resources, including CPU, memory, storage space. etc. To improve the utilization of the system under stable state, we provide some theoretical results about the relationship between the utilization and the stability of the cloud computing system. The conditions for the system to be stable are given for systems with preemptive priority and non-preemptive priority, respectively. Given the stability conditions, we suggest a scheduling algorithm to improve the optimal utilization of the could computing system with preemptive priority and non-preemptive priority, respectively. Numerical results indicate that the two algorithms provide adequate performance on utilization. In addition, the influence of different parameters on the algorithm is investigated as well.

Seven Landsat images were used to assess urban expansion and the corresponding thermal characteristics in Fuzhou City, China between 1985 and 2015. The urban surface thermal patterns were investigated by retrieving land surface temperature using a single-window algorithm based on atmospheric calibration. The built-up area doubled from 1985 (10.6 %) to 2015 (23.4 %), mostly from cropland conversions in the urban fringe, and was closely associated with population increase (R2 = 0.93), gross domestic production GDP (R2 = 0.97), and fixed asset investments (R2 = 0.9139), illustrating the contributions of socioeconomic factors to rapid urban expansion. The daytime heating effect (heat source) in urban areas was strongly related to urban expansion, with a high percentage of an impervious surface usually associated with a high surface temperature. The average range over which wetlands affected built-up area, farmland, and road was 381, 321, and 347 m, respectively. The area of influence on construction land and road was 151 and 11 km2, respectively, whereas the average value for farmland was 147 km2. The area of wetland influence decreased during the study period, and therefore one explanation for the increase in the urban heat island (UHI) in Fuzhou City was the weakened cooling effect of wetland.

An ionic liquid electrospray thruster was developed for application in micro-nano satellites or gravitational wave detectors. The thruster employed a porous ceramic emitter with 7 emitter strips located on its emission surface. Without any liquid-supply device, ionic liquid was delivered through porous media to the emitter strips via capillary effect. Multiple emission sites then formed at the tip of each strip. A charged beam of up to 350 μA (with a current density of 540 μA / cm2) was stably produced in the negative mode. However, in the positive mode, a corona was observed which could prevent the thruster from emitting larger current. A time-of-flight (TOF) mass spectrometer with significantly improved signal-to-noise ratio was built, which was used to obtain the mass distribution of the beam. A retarding potential analysis (RPA) was also performed. The test results showed that the thruster worked in the pure-ion regime, and delivered a maximum thrust of 67.1 μN and specific impulses of 3952 s and 3117 s in the positive and negative modes, respectively.

Routing in Delay Tolerant Networks (DTN) requires nodes to work in a cooperative way. Due to the selfishness nature, the nodes are not willing to use their energy to help others. But two nodes with some relations (friends) are more willing to help each other. In addition, two nodes (not friends) having mutual friends can get help from each other through these mutual friends. This paper proposes a theoretic framework to evaluate the impact of mutual friends on Epidemic Routing (ER). Because the limited energy of nodes will influence their delivery decisions, we establish a model to evaluate the load distribution of ER. Simulations based on real motion traces are made and results show the accuracy of these two models. Further more, for the load distribution, numerical simulations are also considered and results show that most nodes in ER algorithm forward fewer times and only fewer nodes forward more than 5 times.

Recent years have witnessed the rapid deployment of Cyber-Physical Systems (CPS). The wide applications of CPS call for effective design models and methods for resource allocation. As an important part of resource management in CPS, resource allocation problems needed to be solved urgently. In this paper, the framework of resource allocation in CPS is introduce and then scheduling models based on optimization methods to map different jobs with different resources is proposed. Models based on queue theory are also studied to evaluate stability and other parameters of the system which can be used to improve performance of resource allocation methods.

Cloud computing is a computing model based on Internet and computer technology. With the rapid development of cloud computing, scheduling of computing resources is more and more important to cloud systems. Most of the existing researches concerned resource allocation as a problem of task scheduling which is a paradigm of cloud service. In this paper, we consider another paradigm that is user-oriented. In this case, users apply resources from the cloud according to their demands with time interval and amount of computing and we propose a scheduling algorithm based on spectral clustering method through converting the scheduling problem to clustering problem. Experiments show that the scheduling algorithm can obtain fine resource utilization on the premise of QoS.