Sustainable production systems of urban agriculture in the future: a case study on the investigation and development countermeasures of the plant factory and vertical farm in China

IntroductionIn recent years, innovative sustainable agricultural production technologies, including vertical farms and plant factories, have been developing rapidly around the world. The development of plant factories and vertical farms is currently receiving a lot of attention from Chinese academia and industry. However, the recognition and satisfaction of the government, producers, sales companies, and consumers are low, and their attitudes are mixed, mainly due to high pre-construction and post-operation costs, low comprehensive utilization of resources, low product diversity, low market share, high prices, and low core competitiveness, which limit its healthy and sustainable development. This paper designed a questionnaire from the perspectives of industrialization, commercialization, and sustainability in order to understand the respondents' level of awareness, doubts and concerns, purchase intentions and consumption expectations, as well as their trust and recognition of branded products in this new agricultural production system.MethodTo determine the diversity of respondents, this paper examines the group structure of participants from management, research and development, manufacturing, sales, consumers, regional development, and other industrial sectors. The survey was conducted using both face-to-face interviews and electronic questionnaires. As an online survey, the questionnaire was distributed to social groups through social media platforms. A total of 729 valid questionnaires were submitted. For the purposes of categorizing, enumerating, compiling statistics, and analyzing the questionnaires used in this study, descriptive statistics, multi-factor cross-analysis, and other statistical methods were employed. The social roles, functions, and interaction styles of various plant factory practitioners are examined from the perspective of social relationships, and pertinent development concepts and suggestions are proposed based on the survey results.Results and conclusionsThe study found that an increasing number of consumers are understanding and accepting this new form of plant production and are willing to purchase plant products from plant factories and vertical farming. Plant factories and vertical farms are widely regarded as one of the most important methods of future urban agricultural production. Awareness, purchase intent, price expectations, brand awareness, and price expectations of plant factories and vertical farms varied significantly by gender, age, education level, occupation, and income. In addition, there are numerous findings that provide governments, producers, marketers, managers, and consumers with great value and assistance.Development recommendationsWe should take the opportunity of developing plant factories to adjust the structure of the plant industry, enrich the “vegetable basket” of urban residents, increase the supply capacity of the market, enhance agricultural modernization and technological innovation, improve the quality of agricultural products from plant factories, strengthen the brand sales of plant products, and develop more functional plant products with high added value. Through the development of plant factories and vertical farms, we can improve the nutrition and healthy diet structure of citizens' diets, increase the modern plant industry's contribution to the national economy, and promote the comprehensive and sustainable development of the urban productive plant industry

The algal polysaccharide ulvan suppresses growth of hepatoma cells

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Dietary polyphenols as antidiabetic agents: Advances and opportunities

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Label-free immunoassay for porcine circovirus type 2 based on excessively tilted fiber grating modified with staphylococcal protein A

Using excessively tilted fiber grating (Ex-TFG) inscribed in standard single mode fiber, we developed a novel label-free immunoassay for specific detection of porcine circovirus type 2 (PCV2), which is a minim animal virus. Staphylococcal protein A (SPA) was used to modify the silanized fiber surface thus forming a SPA layer, which would greatly enhance the proportion of anti-PCV2 monoclonal antibody (MAb) bioactivity, thus improving the effectiveness of specific adsorption and binding events between anti-PCV2 MAbs and PCV2 antigens. Immunoassay experiments were carried out by monitoring the resonance wavelength shift of the proposed sensor under different PCV2 titer levels. Anti-PCV2 MAbs were thoroughly dissociated from the SPA layer by treatment with urea, and recombined to the SPA layer on the sensor surface for repeated immunoassay of PCV2. The specificity of the immunosensor was inspected by detecting porcine reproductive and respiratory syndrome virus (PRRSV) first, and PCV2 subsequently. The results showed a limit of detection (LOD) for the PCV2 immunosensor of ~9.371TCID50/mL, for a saturation value of ~4.801×103TCID50/mL, with good repeatability and excellent specificity

Orientation-dependent optic-fiber accelerometer based on excessively tilted fiber grating

An orientation-dependent optic-fiber accelerometer based on the excessively tilted fiber grating (ExTFG) inscribed in SM28 fiber is demonstrated, which is based on the optical power demodulation scheme. Without any complicated processing, the cladding mode resonances of the bare ExTFG show high sensitivity to slight perturbation of bending. Due to its excellent azimuth-related bending properties, such a bare ExTFG fixed on a simple cantilever beam has exhibited strong orientation-dependent vibration properties. The experimental results show that a TE mode of the sensor can provide a maximum acceleration sensitivity of 74.14 mV/g at 72 Hz and maximum orientation sensitivity of 9.1 mV/deg while, for a TM mode, a maximum acceleration sensitivity of 57.85 mV/g at 72 Hz and maximum orientation sensitivity of 7.4 mV/deg could be achieved. These unique properties enable the sensor to act as a vector accelerometer for applications in many vibration measurementfields

Lymphoma endothelium preferentially expresses Tim-3 and facilitates the progression of lymphoma by mediating immune evasion

Angiogenesis is increasingly recognized as an important prognosticator associated with the progression of lymphoma and as an attractive target for novel modalities. We report a previously unrecognized mechanism by which lymphoma endothelium facilitates the growth and dissemination of lymphoma by interacting with circulated T cells and suppresses the activation of CD4+ T cells. Global gene expression profiles of microdissected endothelium from lymphoma and reactive lymph nodes revealed that T cell immunoglobulin and mucin domain–containing molecule 3 (Tim-3) was preferentially expressed in lymphoma-derived endothelial cells (ECs). Clinically, the level of Tim-3 in B cell lymphoma endothelium was closely correlated to both dissemination and poor prognosis. In vitro, Tim-3+ ECs modulated T cell response to lymphoma surrogate antigens by suppressing activation of CD4+ T lymphocytes through the activation of the interleukin-6–STAT3 pathway, inhibiting Th1 polarization, and providing protective immunity. In a lymphoma mouse model, Tim-3–expressing ECs promoted the onset, growth, and dissemination of lymphoma by inhibiting activation of CD4+ T cells and Th1 polarization. Our findings strongly argue that the lymphoma endothelium is not only a vessel system but also a functional barrier facilitating the establishment of lymphoma immune tolerance. These findings highlight a novel molecular mechanism that is a potential target for enhancing the efficacy of tumor immunotherapy and controlling metastatic diseases

Modeling and hemodynamic simulation of human arterial stenosis via transmission line model

Arterial stenosis plays a key role in the development and formation of cardiovascular diseases. The effects of arterial stenosis on the global hemodynamic characteristics of human artery tree were studied based on a previously proposed transmission line model of 55 segment arterial tree. Different position, degree and length of the arterial stenosis were simulated to discuss the changes of blood pressure and flow waveform in human arterial tree. The stenosis degree of 50% to 90% were specified to represent a mild, moderate or severe stenosis. Three representative stenosis positions: aorta, carotid and iliac artery were selected. The stenosis length was specified to be 1cm to 4cm. The results of simulation were compared with the literature data. And ankle branchial index (ABI) was calculated to show its relationship with the stenosis position. The results showed that the influence of aorta stenosis on the blood pressure and flow waveforms of upstream artery is more obvious than those of downstream artery; branch artery stenosis has more influence on the blood pressure and flow waveforms of downstream artery than those of upstream artery. When the stenosis degree increased to 80%, the blood pressure and flow waveforms are affected significantly. The stenosis length causes a obvious change in the pressure and flow waveforms of stenosis inlet and outlet. The comparisons of literature and ABI demonstrated that the modeling method is a feasible tool to simulate and study the hemodynamics of the human artery stenosis.17 page(s

Fast Cartoon-Texture Decomposition Filtering Based License Plate Detection Method

Vehicle license plate detection is an important step in automatic license plate recognition, which is prone to be influenced by the background interference and complex environment conditions. It is known that cartoon-texture decomposition split an image into geometric cartoon and texture component, which can remove background interference away from the vehicle image. In this paper, we introduce a fast cartoon-texture decomposition filter into the detection process. Combining the edge detection, morphological filtering and Radon transform based tilt correction method, we formulate a new license plate detection algorithm. Experiment results confirm that the proposed algorithm can remove background interference away, inhibit the emergence of fake license plates, and improve the detection accuracy. Moreover, there is no inner loop iteration in the new algorithm, so it is fast and high-efficiency