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As a unique traditional vegetable oil in China, camellia seed oil has very high edible value. Camellia seed kernel is mainly composed of fatty acids, which not only determines the oil yield of camellia seed, but also exert an important impact on the storage performance of camellia seed. In order to quickly and accurately determine the fatty acid content of camellia seed, this paper took camellia seed as the research object, used hyperspectral technology to determine the fatty acid content of camellia seed, and establishes a spectral model. 8 pretreatment methods, such as Savitzky-Golay smoothing, normalization, baseline correction, multivariate scattering correction, standard normal variable transformation, detrending algorithm, first derivative and second derivative, were adopted in this paper. The spectral prediction model of fatty acid content in camellia seed was established by combining 4 modeling methods: principal components regression (PCR), partial least square regression (PLSR), back propagation neural network (BP), radial basis function neural network (RBF). The optimal prediction model was selected by comparing the coefficient of determination (R

The combination of ultra-wide band (UWB) and inertial measurement unit (IMU) positioning is subject to random errors and non-line-of-sight errors, and in this paper, an improved positioning strategy is proposed to address this problem. The Kalman filter (KF) is used to pre-process the original UWB measurements, suppressing the effect of range mutation values of UWB on combined positioning, and the extended Kalman filter (EKF) is used to fuse the UWB measurements with the IMU measurements, with the difference between the two measurements used as the measurement information. The non-line-of-sight (NLOS) measurement information is also used. The optimal estimate is obtained by adjusting the system measurement noise covariance matrix in real time, according to the judgment result, and suppressing the interference of non-line-of-sight factors. The optimal estimate of the current state is fed back to the UWB range value in the next state, and the range value is dynamically adjusted after one-dimensional filtering pre-processing. Compared with conventional tightly coupled positioning, the positioning accuracy of the method in this paper is improved by 46.15% in the field experimental positioning results.

In order to solve the effects of environmental factors on the droplet settlement of a nutrient solution on plant roots when planting plants with ultrasonic aeroponic cultivation, this study aimed to obtain a suitable wind speed range and atomization time through a nutrient solution atomization experiment, to obtain the best control scheme through a multi-environmental parameter combination cultivation experiment. Taking an ultrasonic aeroponic cultivation device as the research object, and lettuce as the test material, experiments were carried out on two factors affecting the wind speed of an axial fan and the atomization time of the nutrient amount of ultrasonic aeroponic cultivation plants; the suitable wind speed range was 1.0–2.5 m/s. The temperatures of the lettuce root zones in the upper, middle, and lower layers of the ultrasonic aeroponic cultivation device at different time periods were obtained by atomizing the nutrient solution. When the optimum temperature for the root growth of lettuce was 15–20 °C and the wind speed was 1.0–2.5 m/s, the continuous atomization time of the nutrient solution was 66–184 min. Using a quadratic orthogonal rotation combination design method, three main factors, namely wind speed, ambient temperature, and atomization time, were selected to test droplet settlement in the lettuce roots. The droplet settlement in the lettuce root system was measured. The droplet settlement regression equation in the lettuce root system was established. The reliability of the regression model was tested according to the significance condition, and a simplified quadratic orthogonal regression equation was obtained. The main effect analysis, single factor analysis, and interaction effect analysis were used to analyze the model, and the model was further verified. The verification results showed that the relative error between the predicted value and the actual value of the average root droplet sedimentation was 5.8%. The optimum wind speed was 2.5 m/s, the ambient temperature was 16 °C, and the atomization time was 184 min when the ultrasonic aeroponic cultivation device designed in this study was used to cultivate lettuce. It could provide a theoretical reference and an experimental basis for the control of the related growth environment parameters of plants cultivated using ultrasonic aeroponic cultivation.

The aim was to explore the correlations of leukotriene B4 (LTB4) and 25-hydroxyvitamin D3 [25(OH)D3] levels with disease severity in children with Henoch-Schonlein purpura (HSP).A total of 260 HSP children admitted from January 2017 to December 2018 were selected, and 60 healthy children physically examined in the same period were enrolled as controls. The results of general laboratory tests and expression levels of leukotriene B4 (LTB4) and 25-hydroxyvitamin D3 [25(OH)D3] were compared. The correlations of LTB4 and 25(OH)D3 with immunoglobulin A (IgA) were statistically analyzed, and the expression levels of LTB4 and 25(OH)D3 were compared between Henoch-Schonlein purpura nephritis (HSPN) group and non-Henoch-Schonlein purpura nephritis (NHSPN) group. The optimal cutoff values of LTB4 and 25(OH)D3 to predict HSP were analyzed by receiver operating characteristic (ROC) curves, based on which they were divided into low-, intermediate-, and high-risk groups. The length of hospital stay and recurrence rate within 6 months were compared.The levels of white blood cell count, platelets, C-reactive protein, IgA, IgM, IgE, complement C3, and LTB4 were significantly higher and 25(OH)D3 was lower in HSP group than those in control group (p0.05). IgA, LTB4, and 25(OH)D3 levels were independent risk factors for HSP (p0.05). LTB4 was positively correlated with IgA (p0.05), and 25(OH)D3 was negatively correlated with IgA (p0.05). LTB4 level was significantly higher and 25(OH)D3 level was lower in HSPN group than those in NHSPN group (p0.05). The optimal cutoff values of LTB4 and 25(OH)D3 were 27.82 pg/mL and 22.10 ng/mL, respectively, the length of hospital stay gradually increased in low-, intermediate-, and high-risk groups, and the recurrence rates within 6 months were 14.2%, 31.5%, and 39.6%, respectively (p0.05).LTB4 level increases and 25(OH)D3 level decreases in children with HSP, and the expression levels are significantly correlated with disease severity, suggesting predictive values for prognosis.

Vegetable growth requires a relatively stable environment for the root zone. If the temperature in root zone environment is optimal, the aeroponic cultivation will be energy-efficient, and the aeroponic vegetables will grow well at high, normal, or low temperature. By computational fluid dynamics (CFD), this paper numerically simulates the root zone temperature of lettuce in the aeroponic cultivation box, after the box was sprayed with nutrient solutions of different temperatures. Then, the root zone environments of aeroponic lettuce were monitored through experiments at three different temperatures: high temperature, normal temperature, and low temperature. Through comparison, it was learned that the error between the simulated and measured values at each point was smaller than 1.35℃; the maximum error at a single point was within 7.4%; overall, the mean relative error was merely 5.8%. The results prove that the proposed CFD simulation model is reasonable and effective. Our research provides a theoretical reference for optimizing the root zone temperature, regulating the spray of nutrient solutions at different temperatures, and building an energy-efficient efficient aeroponic cultivation system.

Heteroatom-doped porous carbon materials are promising candidates for supercapacitor electrodes, but the simple and low-cost preparation method for heteroatom self-doped carbon, especially derived from biomass, remains a challenge. Herein, we developed a novel strategy that can provide an aerophilic interfacial reaction to produce N, S, P self-doped and oxygen functionalized porous carbon from the outer layer structure of durian peels in facile environment. The obtained porous biochar with N, S, P self-doped and abundant oxygen-containing functional groups can enhance the electrochemical capacitor performance, stability, and hydrophilicity of carbon electrode. When employed into symmetric supercapacitor device, the biochar of functionalization could deliver a specific capacitance of 158.20 F g−1 at 1 A g−1, a high energy density of 21.97 Wh kg−1 at a power density of 500 W kg−1 within a voltage window of 1.0 V and a remarkable cycling durability with 101.35% after 20,000 charge/discharge cycles at 4 A g−1 in 6 M KOH electrolyte. This work provides an effective and economic approach to obtain heteroatom self-doped and highly stable carbon-based electrode materials.

Lithium sulfur (Li-S) batteries are regarded as one of the most promising future energy storage candidates on account of high theoretical specific capacity of 1675 mAh g

Binding and trapping of lithium polysulfide (LPS) are being conceived as the most effective strategies to improve lithium-sulfur (Li-S) battery performance. Therefore, exploiting a simple but cost-effective approach for the absorption and conversion of LPS and the transfer of electrons and Li+ ions is of paramount importance. Herein, sandwich structure MWCNTs@N-doped-C@CoS2 integrated with multiple nanostructures of zero-dimensional (0D) CoS2 nanoparticles, 1D carbon nanotubes (CNTs), and 2D N-doped amorphous carbon layer was obtained, where MWCNTs was firstly uniformly attached with a polydopamine (PDA) of excellent adhesion, followed by hydrothermal method, the Co2+ nanoparticles were in-situ grown on the PDA by the formation of complex compound of Co2+ and N atoms in PDA, and then the CoS2 nanoparticles were in-situ grown on CNTs in a point-surface contact way by a bridging of N-doped amorphous carbon layer derived from the carbonization of attached PDA after the vulcanization at 500 ℃ under Ar atmosphere. The multifunction synergism of absorption, conductivity, and the kinetics of LPS redox is significantly improved, consequently effectively suppressing the shuttle effect and tremendously increasing the utilization rate of active substance. For the Li-S battery assembled with MWCNTs@N-doped-C@CoS2-modified separator, its rate capacity and cycling performance can be greatly enhanced. It can exhibit a high initial discharge capacity of 1590 mAh g-1 at 0.1 C, a stable long-term cycling performance with a relatively low capacity decay of 0.07% per cycle during 500 cycles at 1 C, and a reversible capacity of 772 mAh g-1 and a capacity decay of 0.04% per cycle during 250 cycles at 2 C. Even at a large current density of 4 C, an initial specific discharge capacity of 634 mAh g-1 can still be delivered. With a high sulfur loading of 5.0 mg cm-2, additionally, an outstanding cycling stability can also be well maintained at 685 mAh g-1 at 0.1 C after 50 cycles. This work provides a novel and simple but effective strategy to develop such sandwich hybrid materials comprised of polar metal sulfides and conductive networks via an effective bridging to help realize durable and stable Li-S battery.

Background There is an emerging literature on the mental health of both pre- and post-partum mothers during the coronavirus disease 2019 (COVID-19) pandemic. Methods As of April 1, 2020, 23 mothers confirmed with COVID-19, 15 mothers suspected with COVID-19 but with negative polymerase chain reaction tests, and 33 mothers without COVID-19 (Control Group) were recruited for a study from Hubei Province in China. The Maternal Postnatal Attachment Scale (MPAS), the Zung Self-rating Anxiety Scale, and the Zung Self-rating Depression Scale were applied to investigate the attachment of mothers to their neonates and the postpartum mental health of mothers within the first 3 months after delivery (between 20 to 89 days). Results The period of mother-child separation among the confirmed group (33.9±20.9 days) was significantly longer than that of suspected group (16.7±12.2 days) and control group (10.7±8.4 days). The total score of the MPAS in mothers confirmed with COVID-19 (45.5±4.2) was significantly lower (indicating less mother-child attachment) than that in the suspected (50.5±4.7) and control (48.8±4.6) groups. A negative correlation was noted between the mother-child separation time and the MPAS scores, including the subscale scores of attachment (MPAS acore: Spearman's ρ =-0.33, 95% CI: -0.095 to -0.538, P=0.005; Subscale score of attachment: Spearman's ρ =-0.40, 95% CI: -0.163 to -0.592, P=0.001). The incidence of postpartum anxiety in the confirmed, suspected and control groups was 4.3%, 6.7% and 12.1%, respectively; and the incidence of postpartum depression was 39.1%, 33.3% and 30.3%, respectively. No significant difference was found with regards to maternal postpartum anxiety and depression among the three groups. Conclusions Decreased mother-child attachment found among mothers confirmed with COVID-19, indicates that further intervention is needed to ensure mother-child interaction to appropriately develop attachment. Mother-child attachment experienced disruption due to prolonged mother-child separation necessitated by the COVID-19 management protocol, which needs to be revised to reduce prolonged mother-child separation. Additionally, mothers with and without COVID-19 suffered a high incidence of depression, which warrants further mental health investment for pregnant mothers during the COVID-19 pandemic.

To analyze the pathogenic bacteria, feature of drug resistance and the efficacy of dexamethasone as the auxiliary medication in pediatric refractory purulent meningitis (PM). The 190 refractory PM child patients were selected for the culture of pathogenic bacteria and analysis of drug resistance. In total, 190 pathogenic bacteria were detected, consisting of gram-positive bacteria (77.37%). Of the gram-positive bacteria, the resistance rate of patients with staphylococcus epidermidis, streptococcus pneumoniae or Staphylococcus haemolyticus to levofloxacin was 100%, while in gram-negative bacteria, the resistance rate of patients with klebsiella pneumoniae to gentamycin was 100%. In the observation group, patients had a higher effectiveness rate. Besides, patients in the observation group recovered rapidly from the fever and anomalies in cerebral spine fluid and peripheral white blood cells, and the inflammation was greatly improved. However, difference in the incidence rates of adverse reactions of patients between two groups showed no statistical significance. Pediatric refractory PM involves the pathogenic bacteria, mainly including staphylococcus epidermidis and streptococcus pneumoniae, showing a high resistance to levofloxacin, while the auxiliary medication of dexamethasone can improve the efficacy, and inhibit the inflammation.

Lithium-sulfur battery has been seen as one of the most promising energy storage devices because of its peculiar features such as high energy density, low cost, and environment friendliness. However, the relatively poor cycle stability caused by the shuttle effect of polysulfides (PS) severely limits its further application. The functional modification of separator has been proved to be a meaningful method to improve its cycle stability. Herein, CoSe2@C-N/CNT is synthesized by in-situ growth of carbon nanotubes (CNTs) using metal-organic framework (MOF) as a catalyst and followed by further selenization reaction. Due to its high specific surface area, porous structure and abundant bonding sites, the PS can be effectively captured and also be reversibly released owing to the cross-electron transport network composed of CNTs. Therefore, the lithium-sulfur battery exhibits an excellent performance after its separator is coated and modified by CoSe2@C-N/CNT. The initial discharge capacity of 1224 mA h g−1 can be obtained at 0.5 C current density and the capacity of 975 mA h g−1 after 150 measuring cycles, and furthermore the capacity retention rate can reach 79.7%. Even at 3.0 C high current density, it can still exhibit 798 mA h g−1 initial discharge capacity.

In diesem Kapitel werden die komplexen Einfuhrmoglichkeiten nach China beleuchtet. Fur auslandische Akteure sind auch die rechtlichen Rahmenbedingungen fur die Versendung nach China von groster Wichtigkeit. Zwar ist es immer notwendig, sich mit den aktuellsten Vorschriften zu befassen. Doch ein Blick auf die Entwicklung der vergangenen Jahre hilft auch, um bestimmte Regelmasigkeiten in der Administration und auch Tendenzen fur kunftige Regularien zu erkennen. Besonders zentral sind die Bestimmungen der chinesischen Zoll-, Finanz- und Steuerbehorden.

Im sechsten Kapitel stehen chinesische Zahlungsmethoden im Mittelpunkt, die auch in Deutschland regelmasig fur Schlagzeilen sorgen. Neben den Bargeldzahlungen, die im Reich der Mitte stetig an Bedeutung verlieren, wird auf Kartenzahlung und E-Banking eingegangen. Beim elektronischen Bezahlen uber Drittanbieter wird zwischen Onlinezahlungen und mobilem Bezahlen unterschieden, das in der chinesischen Konsumgesellschaft bereits allgegenwartig ist. Abschliesend werden die fur auslandische Anbieter relevanten Zahlungsmoglichkeiten betrachtet.

Dieses Kapitel fokussiert die logistischen Rahmenbedingungen und die Distributionsmoglichkeiten im chinesischen Einzelhandel. In einem Land mit Stadten so gros wie europaische Lander nimmt auch im Handel die Uberwindung groser Distanzen eine Sonderstellung ein. Im Folgenden werden der Transport uber die wichtigen Hauptrouten, Distribution und Fulfillment sowie Belieferung des Endkunden naher vorgestellt. Abschliesend sind die Logistikkosten im Gros- und Einzelhandel das Thema, bei deren Planung chinesische Kundenerwartungen nicht unterschatzt werden sollten.

Dieses abschliesende Kapitel prasentiert eine Auswahl an Unternehmens- und Praxisbeispielen aus dem grenzuberschreitenden Onlinehandel. Ziel ist es, die bisher vorgestellten Informationen direkt mit dem Handelsalltag in China zu verbinden. Im Mittelpunkt stehen Erfahrungswerte einer Drogeriemarktkette, eines Herstellers von Nahrungserganzungsmitteln und eines Onlinehandlers fur Baby- und Kinderprodukte. Zum Schluss wird noch ein chinesisches Beispiel vorgestellt, das zeigt, wie wichtig es ist, sich an die Konsumentenwunsche und die Marktsituation im schnelllebigen China anzupassen.

Dieses Kapitel stellt einfuhrend den chinesischen Einzelhandel vor. Nach einem allgemeinen Uberblick werden stationarer Handel, Onlinehandel und Cross-Border-E-Commerce naher betrachtet. Anschliesend wird auf die Struktur des Einzelhandels anhand zentraler Eckdaten wie Grosenverhaltnisse, Marktkonzentration und Beschaftigtenzahl eingegangen. Das Kapitel schliest mit einem Blick auf die Konsumenten im heutigen China. Diese Kenntnisse dienen als Grundlage fur mogliche Aktivitaten auslandischer Akteure in China, die in den weiteren Kapiteln thematisiert werden.

Dieses vierte Kapitel befasst sich mit Konsum sowie Marketing und Verkaufsaktivitaten in China. Zu Beginn werden Trends im Onlineverhalten naher betrachtet, wobei Social Media und Suchmaschinen im Mittelpunkt stehen, die auch interkulturell reflektiert werden. Vor diesem Hintergrund wird anschliesend der Umgang mit chinesischen Kunden von der Erstansprache uber den Verkauf bis zur langfristigen Bindung besprochen. Der Schwerpunkt liegt hierbei auf den Moglichkeiten im (grenzuberschreitenden) E-Commerce.

In diesem Kapitel wird die wirtschaftliche Situation Chinas mitsamt einigen demografischen und regionalen Besonderheiten skizziert. Es wird besprochen, dass bei einem kunftigen Wachstum der chinesischen Wirtschaft der private Konsum eine entscheidende Rolle spielen wird. Dabei stehen Einkommensniveau und Sparquote im Fokus, ohne die Konsum und Nachfrage im Land nicht zu verstehen sind. Zuletzt werden mit dem McKinsey-Modell regionale Besonderheiten naher durchleuchtet. Der Uberblick bildet die Wissensbasis fur die anschliesende Betrachtung des chinesischen Einzelhandels.

This paper presents an easy-to-use, power-free, and modular pump for portable microfluidic applications. The pump module is a degassed particle desorption polydimethylsiloxane (PDMS) slab with an integrated mesh-shaped chamber, which can be attached on the outlet port of microfluidic device to absorb the air in the microfluidic system and then to create a negative pressure for driving fluid. Different from the existing monolithic degassed PDMS pumps that are generally restricted to limited pumping capacity and are only compatible with PDMS-based microfluidic devices, this pump can offer various possible configures of pumping power by varying the geometries of the pump or by combining different pump modules and can also be employed in any material microfluidic devices. The key advantage of this pump is that its operation only requires the user to place the degassed PDMS slab on the outlet ports of microfluidic devices. To help design pumps with a suitable pumping performance, the effect of pump module geometry on its pumping capacity is also investigated. The results indicate that the performance of the degassed PDMS pump is strongly dependent on the surface area of the pump chamber, the exposure area and the volume of the PDMS pump slab. In addition, the initial volume of air in the closed microfluidic system and the cross-linking degree of PDMS also affect the performance of the degassed PDMS pump. Finally, we demonstrated the utility of this modular pumping method by applying it to a glass-based microfluidic device and a PDMS-based protein crystallization microfluidic device.