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CRISPR construct design is a key step in the practice of genome editing, which includes identification of appropriate Cas proteins, design and selection of guide RNAs (gRNAs), and selection of regulatory elements to express gRNAs and Cas proteins. Here, we review the choices of CRISPR-based genome editors suited for different needs in plant genome editing applications. We consider the technical aspects of gRNA design and the associated computational tools. We also discuss strategies for the design of multiplex CRISPR constructs for high-throughput manipulation of complex biological processes or polygenic traits. We provide recommendations for different elements of CRISPR constructs and discuss the remaining challenges of CRISPR construct optimization in plant genome editing.

Deep-learning based image quality assessment (IQA) algorithms usually use the transfer learning method that transfers a pre-trained network for classification task to handle IQA task. Although it can overcome the problem of having insufficient IQA databases to some extent, it cannot distinguish between the important and unimportant deep features for the IQA task, which potentially leads to inaccurate prediction performance. In this paper, we propose a no-reference IQA method based on modelling of deep feature importance. A SE-VGG network is developed by using adaptive transfer learning method. It can suppress the features of local parts of salient objects of images that are not important to the IQA task, and emphasize the features of image distortion and salient objects that are important to IQA task. Moreover, the structure of the SE-VGG is investigated to improve the accuracy of the image quality assessment on a small IQA database. Experiments are conducted to evaluate the performance of the proposed method on various databases, including the LIVE, TID2013, CSIQ, LIVE multiply distorted and LIVE challenge. The results show the proposed method significantly outperforms the state-of-the-art methods. In addition, our method demonstrates a strong generalization ability.

The energy-induced peroxydisulfate (PDS) activation is a green and effective approach for pollutant degradation, while the huge energy consumption would significantly increase the cost of wastewater treatment. In this study, by taking carbon nanotubes (CNTs) membrane as the light to heat (LTH) conversion materials, we developed a photothermal PDS activation process for degradation of organic contaminants in a flow-by reactor, with hydroxyl radicals (

The immuno-inflammatory activation triggered by various stresses play an important role in pathophysiology of depression. The immune responses display differential pathological characters in different stresses. However, comparative data and analysis on behavioural, inflammatory and neurochemical changes in different stress-induced depression is limited. To imitate different stressful situations, in this study, mice were subjected to a single injection of LPS (0.5 mg/kg, i.p.) and UCMS (4 week period), respectively. LPS-stressed mice showed more immobility time in FST and TST, as well as more time in periphery in OFT than UCMS-stressed mice. Further, LPS-stressed mice showed robuster expression and release of TNF-α, IL-1β and IL-6 in serum and depression-related brain areas (prefrontal cortex, hippocampus and striatum) as compared to UCMS-stressed mice. The ELISA results showed that IDO expression was significantly increased following LPS and UCMS stresses, but more increased IDO expression was observed in prefrontal cortex and hippocampus of LPS-stressed mice. The decrease of 5-HT and BDNF was detected only in hippocampus of LPS-stressed mice, but in overall all the brain areas assessed in UCMS-stressed mice as compared to control. The data indicate that LPS induced more severe depressive-like behaviours and robuster immune activation than UCMS. Our study strongly imply that hippocampus is relatively more vulnerable to acute inflammatory challenge in depression, while chronic psychological stress is more likely to cause the multidimensional symptoms of clinical depression. Our findings provide more insight into pathophysiology in various stress-induced depression and also implicate a potential suitability of different stress models.

Cellulose paper derived from plants has served as a carrier of cultural inheritance since it was invented 2000 years ago. It attracted more and more attentions in recent years working as a versatile platform to develop functional materials because of its good flexibility, sustainability, biodegradability, low cost and great capability to be modified. Once be functionalized, such as modified with stimuli-responsive polymers, small molecules or inorganic particles, papers may be sensitive to external stimuli from environments and consequently find applications in wide ranges including protein separation, controlled drug release, switchable surfaces, sensoring devices and smart substrates with various colors, etc. However, there are no reviews summarized the progress of such exciting research field. Here in this mini review, we discussed the advantages of cellulose paper as stimuli-responsive substrate and summarized the fabrication techniques, properties and applications of various stimuli-responsive papers reported to date which are triggered by temperature, pH, humidity, ions, light, magnetic field, solvent, gas and biomolecules. Additionally, challenges and outlooks of the future development of such materials were also given in the end.

We present novel techniques for realising reliable low overhead logic functions and more complex systems based on the switching characteristics of memristors. Firstly, we show that memristive circuits have inherent properties for realising multiple valued MIN-MAX operations over the post algebra. We then present an efficient hybrid 1T-4M logic architecture for dual XOR/AND and XNOR/OR functionality, which can be seamlessly integrated with the existing CMOS technology. Although memristors are usually considered to operate at lower frequencies, however, recent advances in technology show their potentiality at high frequencies. To this end, we also explore the effects of high frequencies on their performance and thereby propose reliable high frequency design techniques based on our 1T-4M architectures. Experimental results, based on the design of full adders and multipliers over GF, show that the proposed designs require significantly lower power and overhead while maintaining reliable performance at low as well as at high frequencies compared to the existing techniques.

Nitrate, the end-product of nitrification, tends to accumulate in recirculating aquaculture systems (RASs). We investigated the 96-h acute and 28-d chronic toxicity of nitrate-N to spotted knifejaw, Oplegnathus punctatus. We exposed juveniles (1.3 ± 0.6 g, 2.3 ± 0.7 cm TL) to seven different nitrate-N concentrations (11.3 (control), 673.1, 873.9, 1052.9, 1471.1, 1887.1, or 2368.3 mg/L) in a triplicated experimental design for 96 h; the estimated LC50 values for nitrate-N at 24, 48, 72, and 96 h were 774.4, 678.8, 586.3, and 484.5 mg/L nitrate-N − N, respectively. In an examination of chronic effects of elevated nitrate-N, juvenile O. punctatus (44.9 ± 7.0 g; 7.3 ± 0.6 cm) were exposed to 21.4 ± 4.4 mg/L (treatment 1), 165.5 ± 7.8 mg/L (treatment 2), or 299.4 ± 5.8 mg/L (treatment 3) nitrate-N in triplicated RASs, and the impact of nitrate-N on performance, blood, histological, and gene expression markers was evaluated. After 28 days, final length, specific growth rate and feed conversion ratio did not differ (p > .05) among treatments. Final weight and mortality did not differ significantly between treatments 1 and 2, but was significantly (p

Glutamate-induced excitotoxicity is a contributer to many neurological diseases. Astrocytes may represent a new target for treating glutamate-induced excitotoxicity. However, the in vitro culture system that mimics the in vivo microenvironment is lacking. This study aimed to establish a new in vitro co-culture system including neurons, astrocytes, and endothelial cells (NAE), and to investigate the effect of glutamate-induced excitotoxicity on DNA methylation in astrocytes. A NAE co-culture method was created using a Transwell chamber, in which neurons were seeded on the bottom of the lower chamber, endothelial cells were plated on the top membrane, and astrocytes were plated on the bottom membrane of the insert. Glutamate-induced toxicity was induced using glutamate and glycine, and examined using immunofluorescence and lactate dehydrogenase release assay. Global methylation in astrocytes was analyzed, and the expression of DNMT1 and DNMT3a was examined using Western blot analysis. Glutamate treatment induced less neuronal damage in the NAE system compared with the control group in which neurons and astrocytes were cultured alone. Global DNA methylation was increased and the expression of DNMT1 and DNMT3a in astrocytes was increased after glutamate treatment, which was blocked by application of the NMDAR inhibitor MK-801 and the DNMT inhibitor 5-azaC from the endothelial cells. The in vitro ANE culture system is effective for studying glutamate-induced excitotoxicity, and may be used for testing the passage of drugs across the blood–brain barrier. Inhibition of DNA methylation in astrocytes may be a new therapeutic strategy for treating glutamate-induced excitotoxicity.

Conventional culture method for detecting Group B streptococcus (GBS), a common pathogen of neonatal meningitis and sepsis, is time-consuming and unsensitive. Even though real-time fluorescence PCR-based molecular method is more accurate, it need special instrument and elaborate protocol. Here, we established a novel molecular method combining recombinase polymerase amplification with lateral flow strips for detecting GBS. The cAMP factor (cfb) gene is a highly specific and sensitive biomarker to identify GBS and is detectable by using 100 genomic copies as the amplification template. Clinical performance of this assay was evaluated by testing 130 samples, in comparison with culture method and real-time fluorescence PCR, and the results achieved 100% accuracy, which were the same with those of real-time fluorescence PCR, and were better than those of culture method with false-negative detection. This study provides a rapid and visual method, with clinical potential, for the detection of GBS infection of patients.

Although it has been well recognized that benzene exposure can cause hematopoietic disorders such as aplastic anemia and leukemia, the underlying molecular mechanism remains to be fully understood. Emerging evidence indicated that aryl hydrocarbon receptor (AhR) plays important roles in hematopoietic and immune systems. This study investigated the activation of aryl hydrocarbon receptor (AhR) by hydroquinone (HQ) and its role in HQ-induced DNA damage and apoptosis in cultured human lymphocytes (JHP cells). We also investigated the effect of ROS on AhR activation and functions in JHP cells exposed to HQ with and without regulator including N-acetyl-l-cysteine (NAC), a potent antioxidant, and tert-butylhydroquinone (TBHQ), a Nrf2 activator. Results showed that HQ can cause oxidative stress, DNA damage and apoptosis. Pretreatment of an AhR antagonist (CH223191) can significantly increase the cell survival and mitigate HQ-induced toxicities such as DNA damage and apoptosis. We found that HQ can obviously increase expressions of total protein of AhR and prompt nuclear translocation compared to the control group. Interestingly, NAC can block HQ-induced AhR activation and DNA damage and apoptosis. Conclusively, our results indicated that HQ toxicity is mediated by AhR which is in turn regulated by ROS generated by HQ. The interaction between AhR and ROS drive and amplify the hematopoietic toxicity of HQ. This study provided new insights of mechanism and potential targets for the prevention and treatment to benzene-induced hematopoietic toxicity.

The rolling piston compressor has occupied the compressor market for room air conditioners for years. Compressor efficiency is directly related to the energy efficiency ratio of room air conditioners. As an important replacement of HCFCs, R32 is widely used in the field of refrigeration and air-condition. In this paper, the mass flow rate of refrigerant-lubricant oil mixture in R32 compressor is measured both experimentally and theoretically. In the experiment, influences of minimal clearance, length, geometry of radial leakage channel and minimal clearance of piston face leakage channel on leakage mass flow rate of refrigerant-lubricant mixture, pure lubrication and refrigerant have been investigated in this study. Leakage characteristics and volumetric efficiency of R32 and R410A are respectively compared. Calculation results of the theoretical formulas and the semi-empirical formulas are compared with the experimental results and the semi-empirical formulas have satisfactory reliability and practicality.

The detergent has wide range of applications and plays a critical role in daily life. However, the existing commercial detergents present the drawbacks of irreversible environmental pollution due to their discharge with wastewater. Herein, halloysite clay nanotube (HNT) with unique hollow structure was explored as a green, non-toxic, multifunctional, and cheap detergents. HNT has large aspect ratio, small size, and high adsorption ability, which provides the possibility for removing various stains from different substrates. The increased contact angle and decreased surface tension of HNT dispersion are achieved by increasing the HNT concentration, and HNT tends to stabilize oil-in-water (O/W) Pickering emulsion. The cleaning capacity of HNT on cotton fabric for dyes is almost twice that of laundry powder, indicating that highly efficient cleaning capability of HNT. HNT detergent is also effective to remove ink, tea, and chili oil from textiles with clean efficacy higher than 88%. As kitchen detergent, HNT can effectively eliminates chili oil from ceramic, stainless steel, glass, and plastic plate. Seed germination and crop growth experiment demonstrate that HNT detergent shows no toxicity towards plants and no contamination towards soil. Furthermore, the residue on the cloth of HNT detergent is negligible. Overall, HNT has great potential as an alternative detergent in the future because of its excellent cleaning efficacy and ecological friendliness.

In this study, the accuracy and generality of stress calculation for a plate containing double holes via Schwarz alternating method was investigated. The original Schwarz alternating method with inverse mapping function shows a good performance in terms of the stress solution for a plate containing two arched holes. However, for a plate containing two holes with corners, evitable error may be produced during the calculation because of the unsatisfying accuracy of inverse mapping function. This error is particularly obvious in the stress calculation for a plate containing two triangular holes. To address the problem, an improved Schwarz alternating method without the consideration of inverse mapping function was proposed in this study. The coordinate transformation of points around hole boundaries is realized by an optimization method instead of the inverse mapping function, which leads to little error during the calculation and thus improves the stress solution accuracy especially for plates containing holes with corners. With the employment of the improved method, the influences of connecting angle and lateral pressure coefficient on stress solutions for plates containing double U-shaped holes were discussed. In addition, DEM simulations were further conducted to study the influence of stress characteristics on the failure patterns of rock mass. The result shows that the hoop stress linearly relates to lateral pressure coefficient in the elastic plate and fractures always initiate around hole boundaries where high stress concentrates.

Kiwifruit tends to develop alcoholic off-flavour after long-term storage, leading to decreased fruit market value. Actinidia eriantha ‘White’ and Actinidia deliciosa ‘Bruno’ are two major cultivated kiwifruits in China. Compared to A. eriantha ‘White’, A. deliciosa ‘Bruno’ is prone to developing alcoholic off-flavour associated with ethanol accumulation during storage at ambient conditions without any stresses. In this study, to better understand the complex mechanisms responsible for developing alcoholic off-flavour in kiwifruit during postharvest, transcriptome analysis was used to compare the difference in metabolic pathways between kiwifruits ‘white’ and ‘Bruno’ during ripening at ambient storage. Our results indicated that the development of alcoholic off-flavour in kiwifruit ‘Bruno’ might be associated with three metabolic pathways: the respiration and ethylene metabolisms, starch and sucrose metabolism and ethanol fermentation metabolism. In kiwifruit ‘Bruno’, the higher respiration rate and ethylene production might increase the energy conversion and internal carbon dioxide (CO2) accumulation. Moreover, the higher expressions of starch phosphorylases (SPs), beta-amylases, UDP-glucose pyrophosphorylases (UGPases), sucrose synthases (SSs) and invertases (INVs) accelerated starch degradation along with soluble sugars accumulation in kiwifruit ‘Bruno’, which could provide adequate substrates for ethanol fermentation. In addition, the higher activity of ethanol fermentation metabolism associated with higher expressions of pyruvate kinases (PKs), NADP-dependent malic enzymes (NADP-MEs), pyruvate decarboxylases (PDCs) and alcohol dehydrogenases (ADHs) might directly increase the ethanol production.

Industrially, the Agave tequilana plant is most commonly associated with beverage production, which requires it to be grown for 8–10 year before harvesting. However, its robust growth characteristics and low water usage requirements suggest that it could also be utilized as a substrate for alternative fermentation processes that do not require such long crop turnover times. Therefore, a study was undertaken to characterize the feasibility of utilizing the leaves from two year-old plants as a microbial fermentation biomass substrate. Quantitative saccharification revealed the carbohydrate concentration of two year-old A. tequilana leaves to be 633 mg g−1 dry weight biomass. HPLC analysis identified the primary carbohydrates as glucans, with minor contributions from xylans, galactans, arabinanas, and mannans. Fructose was observed predominantly as inulin. The direct use of unpretreated A. tequilana leaf biomass as a sole carbon source could support yeast growth, however, dilute acid pretreatment removed sufficient levels of carbohydrates to prevent the growth of wild type or inulinase-expressing yeast strains. Up to 133.5 g kg−1 of soluble carbohydrates and 69.6 g kg−1 of soluble inulin were extracted in the pretreatment soakate and 4.0 g kg−1 of soluble carbohydrates and 1.3 g kg−1 of soluble inulin remained in the biomass post processing. Inulinase gene expression did not significantly improve yeast growth rates, but permitted up to 6.3 g kg−1 of the available soluble inulin from the dilute acid pretreatment soakate to be metabolized towards cellular growth.

Vibrio vulnificus is an important foodborne pathogenic bacterium that mainly contaminates seafood. Rapid and accurate technologies that suitable for on-site detection are critical for effective control of its spreading. Conventional detection methods and polymerase chain reaction (PCR)-based and qPCR-based approaches have application limitations in on-site scenarios. Application of loop-mediated isothermal amplification (LAMP) technology was a good step towards the on-site detection. In this study, a recombinase polymerase amplification (RPA)-based detection method for V. vulnificus was developed combining with lateral flow strip (LFS) for visualized signal. The method targeted the conservative empV gene encoding the extracellular metalloproteinase, and finished detection in 35 min at a conveniently low temperature of 37 °C. It showed good specificity and an excellent sensitivity of 2 copies of the genome or 10−1 colony forming unit (CFU) per reaction, or 1 CFU/10 g in spiked food samples with enrichment. The method tolerated unpurified templates directly from sample boiling, which added the convenience of the overall procedure. Application of the RPA-LFS method for clinical samples showed accurate and consistent detection results compared to bioassay and quantitative PCR. This RPA-LFS combined method is well suited for on-site detection of V. vulnificus.

Ceramic filters are a point-of-use (POU) technology applied for water purification in developing regions. Nano-CeO2 modified ceramic filter water purifier (CeO2–CFP) is designed to provide clean potable water and address drinking water safety issues in remote areas. To assess the impact of the entire life cycle of CeO2–CFP on the water environment, a life cycle assessment (LCA)-based water footprint framework was established. The context of remote areas was used to exemplify the calculation of the developed model under different technical scenarios. The production of CeO2–CFP in the high-tech scenario exhibited excellent environmental performance and water resource cost-effectiveness was found to be only 1.59. Raw materials (71.41%) and staff consumption (82.54%) represented the largest share of water footprint in the high-tech and low-tech scenarios, respectively. Sensitivity analysis was proceeded to identify the critical factors affecting the water footprint of CeO2–CFP system and the interactions of these significant factors were investigated. A results-based analysis was carried out in consideration of environmental, social, and economic aspects, and some recommendations for reducing water footprint of CeO2–CFP were formulated.

Safety performance functions (SPFs) are indispensable analytical tools that usually play a crucial role in estimating crash frequencies, identifying hotspots, analyzing crash contributing factors, and assessing the effectiveness of safety countermeasures. Due to the limited availability of safety data, municipalities tended to adopt SPFs from Highway Safety Manual or other neighboring jurisdictions. Recently, boosting algorithms have been frequently exploited for data analysis and statistical regression modeling problems. This research, therefore, aims to examine the efficiency of boosting calibration techniques to transfer the SPF using the limited region data in an international context. To this end, AdaBoost.R2, an adaptive boosting algorithm, Two-stage TrAdaBoost.R2, an instance-based transfer learning algorithm, and Gradient Boosting algorithm were employed to investigate their efficiencies in acquiring knowledge from the available source domain data to predict crashes in the target domain. As a comparison, the calibration factor method was adopted to transfer the traditional negative binomial (NB) regression model. Two training dataset groups were developed to train the four calibration techniques. The first group was used to examine the adaptability of the employed calibration techniques to the limited target region data. While the second group was utilized to further investigate the influence of larger vital information on the performance of transferred models. This study was conducted between two U.S. states, Florida and New York, and two Chinese cities, Shanghai and Suzhou. According to the goodness-of-fit results, boosting calibration techniques showed better prediction accuracy than the calibrated NB-based model using the limited target region data. In addition, the amount and distribution of the training dataset were considered the two significant factors that influence the proficiency of the boosting calibration techniques.

Objective Chemokines regulate infiltration of immune cells to brain in inflammation. Cathepsin C (CatC), a lysosomal protease, has been found to participate in neuroinflammation. However, how CatC affects chemokines expression in neuroinflammation triggered by traumatic brain injury (TBI) remains unclear. Here, we investigated the effects of CatC on chemokines and neuroinflammation in TBI. Methods The present study used CatC knockdown (KD) and overexpression (OE) mice to generate cryogenic brain lesion model and determined effects of CatC on expression of chemokines CCL2, CCL5 and CXCL2 and infiltration of immune cells in acute and chronic phases of the lesion. Further, cellular sources of various chemokines were demonstrated in vitro. Values were compared with wild type (WT) mice. Results The results found that 6 h after lesion, CatC expression,IL-1β and TNF-α mRNA and protein expression were strongly induced in the lesions; CCL2 and CXCL2 mRNA and protein expression were increased in CatC OE mice, while decreased in CatC KD mice. On the 3rd day after lesion, macrophages and neutrophils were mainly infiltrated to the lesions. Simultaneously, Iba-1+ cells in CatC OE mice were increased, while MPO + cells in CatC KD mice were decreased. In contrast, on the 28th day after lesion, a few lymphocytes were infiltrated surrounding new blood vessels. CatC OE mice showed larger volumes of scar areas, higher expression of CCL2,CXCL2,IL-1β,TNF-α,IL-6 and iNOS, as well as stronger GFAP+ and Iba-1+ signals, while CatC KD mice had reversed effects. No significant differences of CCL5 expression were found in various genotype mice. Further, in vitro study demonstrated CatC-induced expression of CCL2 were mainly derived from microglia and neurons, while CXCL2 derived from microglia and astrocytes. Conclusion Our data indicate that CatC aggravates neuroinflammation via promoting production of CCL2 and CXCL2 in glial cells and neurons in a cryogenic brain lesion, providing potential cellular and molecular targets for future intervention of TBI and other neuroinflammatory diseases.

In this study, complex variable theory was employed to study the stress distribution for rock mass containing a hole with complex shapes. The method of mapping function calculation using optimization technique was investigated and improved. The shape-related mapping function was defined for parameter analysis. A new objective function for mapping function determination was developed to calculate related parameters without the consideration of restrictive conditions between boundary points in z-plane and ζ-plane, which significantly simplified the calculation process. In addition, the mapping function for planes containing a rotated hole was deducted to simplify analytical stress solution process for holes under complex stress conditions. Finally, for six kinds of holes with typical shapes in practical rock engineering, the mapping functions were determined, and the external analytical stress distribution were further presented. The analytical solutions combined with numerical and experimental results show that holes with arched boundaries suffer less stress concentration compared with those with corners. Hole shape mainly affects the stability of rock containing a hole via its influence on stress concentration extent around the hole.

The remediation of water that polluted by organic dyes and nanoparticles (NPs) remains a great challenge. However, second pollution of solid waste may produce if the adsorbents are not degradable or recyclable. The stimuli-responsive materials were regarded to be able to resolve this problem by reversible adsorption-desorption under stimuli. Here in this work, the surface of cellulose fibers was modified with CO2-responsive molecules through a simple esterification followed by an aza-Michael addition reaction. The chemical structure was confirmed with Fourier transform infrared spectra (FT-IR), X-ray photoelectron spectroscopy (XPS), x-ray diffractometer (XRD) and thermal analysis. The gas-responsiveness was demonstrated by monitoring of the pH, conductivity and surface zeta potential. Anionic dyes and negative charged NPs in water can be selectively and reversibly captured by the CO2-responsive surface on cellulose fibers, suggesting the inexpensive, readily available and smart cellulose fibers may find great potential in water remediation.

The mechanism between food gelation and its digestibility has attracted increasing attention over the past few decades. This study aimed to evaluate the effect of glycation degree on the gelation and digestibility of egg white gel (EWG) using an in vitro model and a multi-scale characterization of gel structure. Results showed that EWG glycated with increasing d -ribose by covalent bonds exhibited better gelling properties and lower in vitro digestibility according to the appearance of soluble proteins and peptides. Besides, glycation preference for ovotransferrin at lysine might be important for regulating gel structure and proteolysis accessibility via the ratio of fibrous and granular aggregates. Moreover, gel structure was predominant over amino acids modification for digestibility. Binding disorder and steric hindrance could ascribe to the lower digestibility of gels. These findings are enlightening for the formulation and production of food matrix with controlled digestibility through glycation in food and related pharmaceutical fields.

The rolling piston type rotary compressors consume huge amount of energy in buildings due to the large quantity of applications in household as well as commercial air-conditioners and heat pumps. Internal leakage losses significantly affects the energy utilization efficiency of a rolling piston type rotary compressor. This paper experimentally evaluate the internal refrigerant-oil mixture leakage characteristics of a rolling piston type rotary compressor. Effects of minimal clearance, pressure difference, length and geometry of the leakage channel on internal leakage losses are analyzed. The experimental results are compared with prediction results of different mathematical models. A preliminary optimization scheme for the mathematical model is proposed. The updated model can well predict the variation trend of the actual leakage process. Finally, volumetric efficiencies of a rolling piston type rotary compressor prototype under different rotated speeds are obtained based on the updated prediction model. The rolling piston type rotary compressor with high working efficiency will help to reduce the worldwide energy depletion and the present study provides significant reference for design, processing and assembling of the compressors.

Since 2009, the subsidy for large-scale photovoltaic (PV) power plants had been launched, which effectively promoted the development of PV industry. At the same time, negative effects, like serious oversupply of PV industry, were brought about by these large scale governmental subsidies. Although governmental subsidy strongly supports the China PV companies, few of them have competitiveness in the global market. This dramatically conflictive phenomenon attracted many researchers’ attentions in recent years. However, investigations on the best entry and exit occasions of governmental subsidies for the PV industry were rarely reported in previous studies. Therefore, based on the existing division method of enterprise development model, classification of 72 PV companies listed in Shanghai and Shenzhen Stock Exchanges in China was firstly carried out in this paper. This is followed by studying the influence of governmental subsidies on the indexes of different stages of enterprise development. Finally, a conclusion was drawn that the governmental subsidies at Early Exploratory Stage can maximize the social and economic effects, suggesting the best entry occasion, and subsidies at Intermediate Stage and Mature Stage have little effects on its turnover and aggravate the overcapacity of PV supply, suggesting a suitable exit occasion.