The Effect of Water Flow Velocity on Heat Collection Performance of Active Heat Storage and Release System for Solar Greenhouses

In order to explore the influence of water velocity on the heat collection performance of the active heat storage and release system for solar greenhouses,six different flow rates were selected for treatment in this experiment.The comprehensive heat transfer coefficient of the active heat storage and release system at the heat collection stage was calculated by measuring the indoor solar radiation intensity,indoor air temperature and measured water tank temperature.The prediction model of water temperature in the heat collection stage was established,and the initial value of water temperature and the comprehensive heat transfer coefficient were input through MATLAB software.The simulated value of water temperature was compared with the measured value and the results showed that the best heat transfer effect could be achieved when the water flow speed was 1.0 m3h-1.The average relative error between the simulated water tank temperature and the measured value is 2.70-6.91%.The results indicate that the model is established correctly,and the variation trend of water temperature can be predicted according to the model in the heat collection stage.

A Preliminary Study of Rotundine-Polyion Complex Release System

A rotundine-polyion complex(PIC)release system was prepared first by granulation of rotundine containing chitosan acetate solution and then by complexing with carboxymethyl glucomannan(CMGM)solution on the granular surface.The granules have an average diameter of 1.38-1.53 mm and the drug content reaches 62.89％.The external release tests showed T_(50) to be 45 rain and the total release time 4 h in an artificial gastric juice,while no more than 60％ of the drug was released in the same period of time in an ar- tificial intestinal fluid.The various factors affecting the external release were examined.

Light and temperature dual responsive pesticide release system based on mesoporous silica nanoparticles modified by dopamine

A light and temperature dual responsive copolymer,poly(7-(4-vinylbenzy-loxyl)-4-methylcoumarin-co-N vinyl caprolactam-co-tri(ethylene glycol)methyl ether methacrylate)(PVNM),was grafted on the surface of dopamine based mesoporous silica nanoparticles(MSNs).The resulting polymer brush,MSNs-g-PVNM,was characterized by FT-IR,TEM,TGA and XPS.The dual responsive behaviors of MSNs-g-PVNM were systematically studied.With imidacloprid as the model guest pesticide,the loading percentage and loading efficiency of the polymer brush were determined as 9.2%and 40.6%,respectively.The release efficiency of imidacloprid in MSNs-g-PVNM was the lowest value of 5.4%at 20℃ and 365 nm,and it reached the highest value of 52.4%at 50℃ and 254 nm.The loss percentage of imidacloprid on the leaves contained imidacloprid-loaded MSNs-g-PVNM(8.4%)was much less than that contained only imidacloprid(25.2%)after three rinses.It was confirmed that the release process of imidacloprid was well regulated through changing external conditions such as light and temperature.

Polymeric microneedle-mediated sustained release systems: Design strategies and promising applications for drug delivery

Parenteral sustained release drug formulations, acting as preferable platforms for longterm exposure therapy, have been wildly used in clinical practice. However, most of these delivery systems must be given by hypodermic injection. Therefore, issues including needle-phobic, needle-stick injuries and inappropriate reuse of needles would hamper the further applications of these delivery platforms. Microneedles (MNs) as a potential alternative system for hypodermic needles can benefit from minimally invasive and self-administration. Recently, polymeric microneedle-mediated sustained release systems (MN@SRS) have opened up a new way for treatment of many diseases. Here, we reviewed the recent researches in MN@SRS for transdermal delivery, and summed up its typical design strategies and applications in various diseases therapy, particularly focusing on the applications in contraception, infection, cancer, diabetes, and subcutaneous disease. An overview of the present clinical translation difficulties and future outlook of MN@SRS was also provided.

Construction of hollow polydopamine nanoparticle based drug sustainable release system and its application in bone regeneration

Nanomaterial-based drug sustainable release systems have been tentatively applied to bone regeneration.They,however,still face disadvantages of high toxicity,low biocompatibility,and low drug-load capacity.In view of the low toxicity and high biocompatibility of polymer nanomaterials and the excellent load capacity of hollow nanomaterials with high specific surface area,we evaluated the hollow polydopamine nanoparticles(HPDA NPs),in order to find an optimal system to effectively deliver the osteogenic drugs to improve treatment of bone defect.Data demonstrated that the HPDA NPs synthesized herein could efficiently load four types of osteogenic drugs and the drugs can effectively release from the HPDA NPs for a relatively longer time in vitro and in vivo with low toxicity and high biocompatibility.Results of qRT-PCR,ALP,and alizarin red S staining showed that drugs released from the HPDA NPs could promote osteogenic differentiation and proliferation of rat bone marrow mesenchymal stem cells(rBMSCs)in vitro.Image data from micro-CT and H&E staining showed that all four osteogenic drugs released from the HPDA NPs effectively promoted bone regeneration in the defect of tooth extraction fossa in vivo,especially tacrolimus.These results suggest that the HPDA NPs,the biodegradable hollow polymer nanoparticles with high drug load rate and sustainable release ability,have good prospect to treat the bone defect in future clinical practice.

Hybrid lipopolymer vesicle drug delivery and release systems

Hybrid lipopolymer vesicles are membrane vesicles that can be self-assembled on both the micro-and nano-scale.On the nanoscale,they are potential novel smart materials for drug delivery systems that could combine the relative strengths of liposome and polymersome drug delivery systems without their respective weaknesses.However,little is known about their properties and how they could be tailored.Currently,most methods of investigation are limited to the microscale.Here we provide a brief review on hybrid vesicle systems with a specific focus on recent developments demonstrating that nanoscale hybrid vesicles have different properties from their macroscale counterparts.

Construction and Development of China’s Earthquake Information Release System

Focused on the current situation,monitoring system,technical management regulation,process,system composition,and information publication of the earthquake information release,we summarized the construction and development of China’s earthquake information release system and expected its future.In general,China’s earthquake information release systems is able to publish auto-results with MS≥3.0 from 1 to 3 minutes,M_S≥6.0 in global from 2 to 30 minutes,and formal results with MS≥3.0 in China from 8 to 30 minutes,MS≥6.0 in global from 20 to 60 minutes.These earthquake information is released by various channels such as short message,website,microblog,mobile application,etc.

Design of a Mechanical Release System of Predator Insects to Control the Colorado Potato Beetle, Leptinotarsa Decemlineata （Say）

The CPB （Colorado potato beetle）, Leptinotarsa decemlineata （Say）, is the major insect pest of potato crops in North America, Europe and Asia. Large amounts of chemical insecticides are used to control this insect pest. Also, the CPB has developed over the years a resistance to most of the registered chemical insecticides, including those that were effective at one time. One of the most promising alternatives to chemical insecticides consists of taking advantage of natural enemies. The use of the stinkbug predator Perillus bioculatus to control the CPB has been successful at small scale. However, this natural enemy is not abundant in the nature and its hand release at large scale is not realistic. To remedy to this problem, predators must be massively released in potato fields using a mechanical distributor. Such a machine has been successfully designed and built at the Department of Soils and Agri-Food Engineering of University Lavak In this distributor, masses of predators are placed in small containers and mixed with a carrier material. In the field, the containers are mechanically opened at different locations, based on a source-point mass release option. These locations are determined in advance following a field monitoring of the populations of CPBs. Field trials proved that the mechanical distributor is reliable and ease of use. Its efficiency in releasing insect predators is high and comparable to that obtained in previous laboratory tests.

KINETICS OF DIFFUSION-CONTROLLED DRUG MATRICES RELEASE SYSTEM

A refined double integral method has been applied to the problem encountered in the diffu-sion release of a drug from a polymeric matrix.The finite external mass transfer resistance has alsobeen incorporated into the present analysis.Experimental release rates of 5-fluorouracil fromethylene-vinyl alcohol copolymer into distilled water were measured in order to test the applicabilityof these models.All system parameters were measured by experiments and models were built up.Themodels presented here are much more accurate than Higuchi model and much easier than the exactsolutions.In view of accuracy,the models are almost the same as the exact solutions.The experi-mental release data agree Well with the computed

Novel Gelatin-Adriamycin Sustained Drug Release System for Intravesical Therapy of Bladder Cancer

To reduce recurrence in the patients with bladder cancer after tumor removal through open surgery or transurethral resection, a form of gelatin adriamycin sustained drug release system was developed and its release kinetics both in vitro and in vivo , its efficacy in inhibiting BIU 87 bladder tumor cell growth in vitro and its safety in vivo were studied. The results showed that this system controlled adriamycin release over a period of 21 days in vitro and significantly inhibited BIU 87 cell growth. When this system was injected into rabbit bladder, it sustained adriamycin release for 12 days and the released drug could diffuse 1 cm around the injection point. No major complications were observed except minor acute nonspecific cystitis that could be tolerated well by the animals. This study suggests the possibility of applying this system locally in treating bladder cancer..

Design of Atomic Time Scale Release System for Multiple Laboratories

The atomic time scale release system for multiple laboratories is completed by modular design according to the atomic clock data provided by eight domestic punctual laboratories.The system includes the three modules,the processing of atomic clock data,the calculation of atomic time scale and the release of atomic time scale data,using MATLAB for data processing and time scale calculation,and using GUI for data visualization design.The system has clear process of the algorithm,simple function modules and friendly human-machine interface.The operation results of actual data show that the time difference between the integrated atomic time scale of the system and UTC is better than±10ns,and the content of data release can meet the needs of the scientific research in related fields in China.

A matrix metalloproteinase-responsive hydrogel system controls angiogenic peptide release for repair of cerebral ischemia/reperfusion injury

Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug delivery often results in a burst release of the drug,leading to transient retention(inefficacy)and undesirable diffusion(toxicity)in vivo.Therefore,a drug delivery system that responds to changes in the microenvironment of tissue regeneration and controls vascular endothelial growth factor release is crucial to improve the treatment of ischemic stroke.Matrix metalloproteinase-2(MMP-2)is gradually upregulated after cerebral ischemia.Herein,vascular endothelial growth factor mimic peptide QK was self-assembled with MMP-2-cleaved peptide PLGLAG(TIMP)and customizable peptide amphiphilic(PA)molecules to construct nanofiber hydrogel PA-TIMP-QK.PA-TIMP-QK was found to control the delivery of QK by MMP-2 upregulation after cerebral ischemia/reperfusion and had a similar biological activity with vascular endothelial growth factor in vitro.The results indicated that PA-TIMP-QK promoted neuronal survival,restored local blood circulation,reduced blood-brain barrier permeability,and restored motor function.These findings suggest that the self-assembling nanofiber hydrogel PA-TIMP-QK may provide an intelligent drug delivery system that responds to the microenvironment and promotes regeneration and repair after cerebral ischemia/reperfusion injury.

Construction and properties of venlafaxine hydrochloride sustained release system based on hollow mesoporous silica microspheres

The aim of this work is to develop a venlafaxine hydrochloride sustained release system based on hollow mesoporous silica microspheres(HMSMs).HMSMs were innovatively prepared with tetraethyl silicate(TEOS)as the precursor and volatile n-heptane as a soft template.The obtained HMSMs show a well-defined hollow structure with an average size of 967 nm and pore volume of 0.85 cm^(3)/g,implying it is a potential drug carrier.Subsequently,venlafaxine hydrochloride(VF)was absorbed in the HMSMs with a content of 37.67% or so.The sustained release effect is further measured by the dissolution in-strument at 37℃ and 50 rpm in ultrapure water.The results showed that the HMSMs/VF system shows good sustained release properties compared with sustained release tablets with hydroxypropyl meth-ylcellulose as the main component.This HMSMs sustained release system appears to be a promising candidate for a sustained drug release.

Laws of strata energy release and corresponding safety warning system in metal mine

The strata deformation in mining area was monitored in Dabaoshan copper-iron mine,and an analytical method of strata energy release was put forward.On the basis of chaotic theory,by reconstructing the phase space for time series data of strata energy release,the saturated embedding dimension and the correlation dimension of the dynamic system were obtained to be 4 and 1.212 8,respectively,and the evolution laws of distances between phase points of strata energy release in the phase space were revealed.With grey theory,a prediction model of strata energy release was set up,the maximum error of which was less than 6.7%.The results show that there are chaotic characters in strata energy release during mining;after reconstructing phase space,the subtle changing characteristics of energy release can be magnified,and the internal rules can be fully demonstrated.According to the laws,a warning system for strata stability in mining area was established to provide a technical safeguard for safe mining.

RELEASE KINETICS OF MONOLITHIC MATRIX COATED WITH OUTER MEMBRANE SYSTEM

The reservoir-monolithic type of the controlled release systems is investigated currently,however,the existing kinetic model could not describe the release process well because the release kinetics is rather complicated.In this paper,a simplified release kinetic model for diffusion-controlled monolithic matrix coated with outer membrane systems is proposed and verified by the experimental data of mercaptopurinum release experiment.It shows that the model can well describe the release mechanism (the relative error is under 3%) when drug loading (C d) is above its solubility limit (C s).At the same time,the release characteristics of special cases (D mD f and D mD f) are discussed theoretically.When D mD f the release rate becomes constant,namely,zero order release,and the release rate is independent of the drug membrane.This result provides the theoretical basis for the system of zero order release as well as how to control the release rate and the amount of drug release.When D mD f,the release rate is dependent on the drug release coefficient in the monolithic matrix,solubility and drug loading but independent of the process in the outer membrane,and it is similar to monolithic matrix type.

Effect of Continuous Application of Controlled Release Nitrogen Fertilizer in Various Types of Soil in Dong-Ting Lake Region under Double Rice Cropping System

[Objective] This study aimed to explore the effects of continuous application of controlled release nitrogen fertilizer under double rice cropping system. [Method] By modeling three types of paddy soils in Dong-Ting Lake area, four treatments as no fertilizer （CK）, urea, controlled release nitrogen fertilizer （CRNF） and 70% controlled release nitrogen fertilizer （70% CRNF） were designed in the micro-plot trials from 2005 to 2008. [Result] The rice yield in treatment CRNF at N 150 kg/hm2 was increased by 10.3%, 8.0% and 2.4% compared with treatment of urea, in alluvial sandy loamy paddy soil （ALS）, purple calcareous clayey paddy soil （PCS）, and reddish yellow loamy paddy soil （RYS）, respectively; and the yield in treatment of 70% CRNF was increased by 6.1%, 2.6% and -0.8%, respectively. The ranking order of nitrogen uptake amount by plant in early rice and late rice was CRNF 70% CRNF urea CK in all three types of soil. Nitrogen utilization efficiency of CRNF in above three types of soil was 60.7%, 59.6% and 56.3%, increased by 23.8%, 19.4% and 16.3% compared with that in treatment of urea, respectively. Nitrogen utilization efficiency of CRNF in early rice was increased year by year, and was higher than that of 70% CRNF during the whole experiment stage, while that in late rice was increased first and then decreased from the 3rd year. [Conclusion] Continuous application CRNF could alleviate the decreasing of soil nitrogen fertility and organic carbon especially in ALS, increase rice yield and nitrogen utilization efficiency in double-rice cropping system.

Impacts of soil fauna on nitrogen and phosphorus release during litter decomposition were differently controlled by plant species and ecosystem type

The dynamics of litter nitrogen (N) and phosphorus (P) release could be affected by soil fauna and environmental conditions. The objective of the present study was to investigate the effects of soil fauna on the dynamics of N and P during foliar litter decomposition in three types of ecosystems (i.e., montane forest, ecotone, and dry valley) along an elevation gradient. A field experiment using litterbags with two different mesh sizes (0.04 and 3 mm) was conducted from November 2013 to October 2014. Nitrogen and P release rates in decomposing foliar litter from fir (Abies faxoniana) and birch (Betula albosinensis) in montane forest, oak (Quercus baronii) and cypress (Cupressus chengiana) in ecotone, and cypress and clovershrub (Campylotropis macrocarpa) in dry valley were investigated in the upper reaches of the Yangtze River. Soil fauna strongly affected N and P release across different decomposition periods and ecosystem types. The average release rate of N mediated by soil fauna across the entire year was higher in the dry valley (15.6–37.3%) than in the montane forest (0.5–6.4%) and the ecotone (- 3.7–4.9%). The effects of soil fauna on P release rate were manifest in both the montane forest and the dry valley. Moreover, the impacts of soil fauna can vary substantially among different decomposition periods. Our results indicated that soil fauna can significantly affect N and P release during litter decomposition. The N release rate mediated by fauna was likely to be more sensitive to the effects of plant species (i.e., initial litter chemical traits), while the P release rate mediated by soil fauna might be subject to the effects of local-scale environmental factors (e.g., temperature) to a greater extent.

Halloysite Nanotube Composited Thermo-responsive Hydrogel System for Controlled-release

Halloysite nanotube-composited thermo-responsive hydrogel system has been successfully developed for controlled drug release by copolymerization of N-isopropylacrylamide （NIPAM） with silane-modified halloysite nanotubes （HNT） through thermally initiated free-radical polymerization. With methylene blue as a model drug, thermo-responsive drug release results demonstrate that the drug release from the nanotubes in the composited hy-drogel can^be well controlled by manipulating the environmental temperature. When the hydrogel network is swol- len at temperature below the lower critical solution temperature （LCST）, drug releases steadily from lumens of the embedded nanotubes, whereas the drug release stops when hydrogel shrinks at temperature above the LCST. The release of model drug from the HNT-composited hydrogel matches well with its thermo-responsive volume phasetransition, and shows characteristics of well controlled release. The design strategy and release results of the pro- posed novel HNT-composited thermo-responsive hydrogel system provide valuable guidance for designing respon- s_i_ve nanocomposites for controlled-release of active agents.

Inhibitory effect of lanosterol on cataractous lens of cynomolgus monkeys using a subconjunctival drug release system Keke

Background:To evaluate the effect of lanosterol on cataractous lens of cynomolgus monkeys using a subconjunctival drug release system.Methods:Nine elder cynomolgus monkeys were used,consisting of three monkeys without cataract as controls,three monkeys with naturally occurring cortical cataract,and three monkeys with nuclear cataract as intervention groups.Nanoparticulated thermogel with lanosterol and fluorescein was administered by subconjunctival injection in the monkeys with cataract.Fluorescence changes of injected thermogel and cataract progression were observed.Lanosterol concentration in aqueous humor,solubility changes in lens proteins,and oxidative stress levels were analyzed in the lenses of the control and intervention groups.Results:Injected thermogel showed decreased fluorescence during follow up.Lanosterol concentration in aqueous humor increased in the first 2 weeks and then gradually decreased,which was in accordance with the changes in cortical lens clarity.However,lenses with nuclear opacification showed little change.In the cortical region of lenses with cortical cataract,solubility ofα-crystallin was significantly increased after administration of lanosterol,as well as the reduction of oxidative stress.Conclusions:We demonstrated the effect of lanosterol on cataract progression based on in vivo models of primates.Lanosterol showed a short-term and reliable reversal effect on reducing cataract severity in cortical cataract in the early stages,possibly due to the increase in the solubility of lens proteins and changes in the oxidative stress status.Lanosterol administration using subconjunctival drug release system could be a promising nonsurgical approach for future clinical studies of cataract prevention and treatment.

Sustained-release drug delivery systems for the treatment of glaucoma

Glaucoma,a leading cause of irreversible blindness,affects more than 64 million people worldwide and is expected to grow in number due to the aging global population and enhanced methods of detection.Although topical therapies are often effective when used as prescribed,the drawbacks of current medical management methods include poor patient adherence,local and systemic side effects,and in some cases,limited therapeutic efficacy.Novel ocular drug delivery platforms promise to deliver differentiated drug formulations with targeted delivery leveraging patient-independent administration.Several platforms are in various stages of development with promising pre-clinical and clinical data.The Bimatoprost Sustained Release (SR) intracameral implant was approved in the United States in March of 2020,making it the first long-term injectable therapy available for the treatment of glaucoma.This review aims to provide an update on novel sustained release drug delivery systems that are available today as well as those that might be commercialized in coming years.