Effect of electrochemically dealloying Ti6Al4V abutments on human gingival fibroblasts / 口腔疾病防治

Objective@#To investigate the effects of electrochemically dealloying of Ti6Al4V abutments on human gingival fibroblasts (HGFs) and to provide experimental evidence for surface modification of implant abutments.@*Methods@#The samples were divided into an NC group (negative control, no other treatment on a smooth surface), an NM-1 group (nanomesh-1, electrochemical dealloying treatment in 1 mol/L NaOH 1 h on 2 V voltage), and an NM-2 group (nanomesh-2, electrochemical dealloying treatment in 5 mol/L NaOH 1 h on 2 V voltage). The surface morphologies of the samples and the adhesion of HGFs on the sample surfaces were observed with scanning electron microscopy (SEM). The surface hydrophilicities of the samples were measured with a contact angle measuring instrument. The proliferation of HGFs on the different samples were evaluated with CCK-8, and the expression of adhesion-related genes, including collagen Ⅰ (COL1A1), collagen Ⅲ (COL3A1), fibronectin 1 (FN1), focal adhesion kinase (FAK), vinculin (VCL), integrin α2 (ITGA2), and integrin β1 (ITGB1), on the different samples was measured with qRT-PCR. The expression of vinculin on the surfaces of HGFs was observed via confocal laser scanning microscopy (CLSM) after immunofluorescent staining. Collagen fiber secretion and syntheses of HGFs from different samples were evaluated via Sirius red staining.@*Results@#SEM revealed the formation of ordered and uniform three-dimensional mesh structures on the surfaces of the NM-1 and NM-2 groups, with grid diameters of approximately 30 nm for the NM-1 group and approximately 150 nm for the NM-2 group. Compared with that of the NC group, the water contact angles of the NM-1 group and NM-2 groups were significantly lower (P<0.000 1). Cell proliferation in the NM-1 group was significantly greater than that in the NC group (P<0.01). Moreover, there was no significant difference in the water contact angles or cell proliferation between the NM-1 group and the NM-2 group. SEM revealed that HGFs were adhered well to the surfaces of all samples, while the HGFs in the NM-1 and NM-2 groups showed more extended areas, longer morphologies, and more developed pseudopodia than did those in the NC group after 24 h. qRT-PCR revealed that the expression levels of the adhesion-related genes COL1A1, COL3A1, FN1, FAK and VCL in the NM-1 group were significantly greater than those in the NC and NM-2 groups (P<0.01). The expression of vinculin protein in the NM-1 group was the highest, and the number of focal adhesions was greatest in the NM-1 group (P<0.01). The results of Sirius red staining showed that the NM-1 group had the highest secretion and syntheses of collagen fibers (P<0.000 1).@*Conclusion@#The three-dimensional nanomechanical structure of Ti6Al4V modified by electrochemical dealloying promoted the adhesion, proliferation, collagen fiber secretion and syntheses of HGFs, and electrochemical dealloying of Ti6Al4V with a grid diameter of approximately 30 nm obviously promoted HGF formation.

CHALLENGES IN IMPLEMENTING SMART ENERGY METERS IN INDIA

Introduction: Smart Energy Meter (SEM) is an electronic device used to measure, record and transmit the consumption of electricity, gas or water. The smart energy meter is a vital component of a smart grid, which is an advanced power distribution infrastructure that uses digital communication technology to monitor, control and optimize the ow of electricity between power producers and consumers. India, like other developing countries, faces several challenges in the implementation of smart energy meters. This paper examines the challenges in implementing smart energy meters in India and proposes solutions to overcome these challenges.

Influence of personality traits on mental health and mediating role of work-family support among front-line power grid workers / 环境与职业医学

Background Front-line power grid workers are required to face a variety of occupational hazards (such as aerial work), which make them susceptible to psychological problems and further reduce their performance efficiency and safety level. Objective To investigate the mental health status of front-line power grid workers and explore the influence of personality traits on mental health and the potential mediating role of work-family support between them. Methods This study was designed as a cross-sectional study. From January to June 2019, a cluster random sampling method was used to select two of the 20 power supply stations owned by a Guangdong power company. A total of 485 front-line power grid workers were included in the study. Sociodemographic characteristics were investigated, and NEO Five-Factor Inventory, Work-Family Support Scale, and Symptom Checklist 90 (SCL-90) were used in the survey. Spearman correlation analysis was conducted to analyze the correlations between measured variables. Structural equation modeling was used to analyze the relationships of personality traits, work-family support, and mental health, and Bootstrap analysis was used to test the mediating effect of work-family support on the relationship of personality traits and mental health. Results The M (P25, P75) of total SCL-90 score was 134.00 (110.00, 167.00）, and 139 (28.66%) front-line power grid workers showed positive mental health symptoms. The correlation analysis indicated that among the front-line power grid workers, neuroticism score was negatively correlated with work-family support total score (rs=−0.356, P<0.001), and positively correlated with the total score of SCL-90 (rs=0.557, P<0.001) as well as all the scores of its sub-dimensions (rs=0.436-0.550, P<0.001). Openness score was positively correlated with work-family support total score (rs=0.269, P<0.001), and except for paranoid ideation (P>0.05), openness score was negatively correlated with the scores of all the other sub-dimensions of SCL-90 (rs=−0.091-−0.147, P<0.05). The scores of the other three personality traits (extroversion, agreeableness, and conscientiousness) were positively correlated with work-family support total score (rs=0.331-0.466, P<0.001), and negatively correlated with the total score of SCL-90 as well as the scores of all its sub-dimensions (P<0.001). The modified structural equation modeling indicated that the direct effect of work-family support on mental health symptoms was −0.225 (P<0.001). The direct effects of extraversion and openness on work-family support were 0.241 (P<0.001) and 0.123 (P<0.05), respectively, while the effect on mental health symptoms was not statistically significant. The direct effects of neuroticism on work-family support and mental health symptoms were -0.152 (P<0.01) and 0.467 (P<0.001), respectively. The direct effects of conscientiousness on work-family support and mental health symptoms were not statistically significant (P>0.05). The direct effect of agreeableness on work-family support was not statistically significant (P>0.05), while the direct effect on mental health symptoms was −0.180 (P<0.001). Conclusion The front-line power grid workers show a high score of SCL-90. Workers with higher neuroticism are more vulnerable to mental health symptoms. Work-family support fully mediates the effects of extraversion and openness on mental health symptoms, and partially mediates the effects of neuroticism on mental health symptoms, while does not mediate the effects of agreeableness on mental health symptoms. Sufficient work-family support may improve mental health status.

Study on the effect of virtual grid on chest X-ray image quality / 中华放射学杂志

Objective:To explore the image quality and its evaluation method using virtual grid under different tube voltages in the clinical chest X-ray exam.Methods:According to the conditions of chest X-ray photography commonly used in clinical practice, the corresponding thickness of plexiglass (20 cm, including CDRAD phantom) was determined as the experimental object. With a fixed tube loading of 4 mAs and the tube voltage from 60 to 125 kV, the experimental object was imaged in three ways: physical grid, none grid and virtual grid. The common physical parameters (CNR, σ, C, SNR), texture analysis (Angular second moment, texture Contrast, Correlation, Inverse difference moment, Entropy) and CDRAD phantom score (IQF inv) were evaluated. Two-way ANOVA test was used for each group of common physical parameters, and further pairwise comparisons were made. At the same time, applying virtual grids on the obtained images with chest anthropomorphic model and texture indexing the images with and without virtual grids, then rank sum test of paired sample can be conducted. Results:There were differences in image quality among the three groups of grid mode( P<0.05), and the physical grid delivered the best image quality. The tube voltage had an impact on all image quality evaluation indexes ( P<0.05). The tube voltage was positively correlated with CNR, SNR, angular second moment, inverse difference moment and IQF inv ( P<0.05), and negatively correlated with σ, C, texture contrast and entropy ( P<0.05). There was no significant correlation between the tube voltage and Correlation ( P>0.05). The chest anthropomorphic model images were used to evaluate the virtual grids, and the texture indexes (Angle second moment, Contrast, Correlation, Inverse difference moment, Entropy) were statistically significant (P<0.05). Conclusions:The virtual grid can improve the image quality of chest X-ray photography, and the image texture analysis method can be a useful supplement to the image quality evaluation parameters.

Investigation of occupational hazard emergencies in power grid enterprises in three regions from 2018 to 2020 / 中国职业医学

Objective: To analyze the occurrence and risk factors of various occupational hazard incidents in China's power grid enterprises. Methods: A total of 4 191 workers from eight power grid enterprises in Jilin Province, Shandong Province, and Chongqing City were selected using a convenience sampling method. Their exposure in workplace and the occurrence of various occupational hazard incidents from 2018 to 2020 were investigated. Results: Among the participants, 71.7% were engaged in outdoor operations. The incidence rates of occupational hazard emergency, ranking from high to low, were electric ophthalmia, acute mountain sickness, heatstroke, electro-flash dermatitis, sunburn, cold injury, solar ophthalmia, and gas poisoning in confined space, with the rate of 42.3%, 42.3%, 38.1%, 24.3%, 17.4%, 16.5%, 10.0%, and 1.3%, respectively (P<0.01). The results of multivariate logistic regression analysis showed that workers in Jilin Province had a higher risk of cold injury compared to those in Shandong Province and Chongqing City (all P<0.01). Workers in Chongqing City had a higher risk of solar ophthalmia than those in Jilin Province (P<0.01). Workers in inspection and maintenance positions had a higher risk of heatstroke and sunburn compared to those in substation positions (all P<0.05). Power grid workers with protective systems in enterprises had a lower risk of sunburn and solar ophthalmia compared to those without protective systems (all P<0.01). The risks of sunburn and solar ophthalmia among power grid workers increased with age and daily outdoor working time (all P<0.05). Taking protective measures was a protective factor against heatstroke and cold injury (all P<0.01). Conclusion: Power grid workers face the risk of various occupational hazard incidents. Relevant organizations should conduct targeted preventive measures based on regional and worker characteristics, and ensure the implementation of protective systems in different work environments.

SOLAR ENERGY GRID INTEGRATION SYSTEMS

Solar Energy Grid Integration Systems (SEGIS) concept helps in achieving high penetration of photovoltaic (PV) systems into the utility grid. Advanced, integrated inverter/controllers will be the enabling technology to maximize the bene?ts of residential and commercial solar energy systems, both to the systems owners and to the utility distribution network as a whole. Advanced integrated inverters/controllers may incorporate energy management functions and/or may communicate with separate-alone energy management systems as well with utility energy portals, such as smart metering systems. The value of the energy provided by these solar systems will in turn be increased through advanced communication interfaces and controls.

Clinical observation on wound measurement grid and perforator flap design / 中华显微外科杂志

Objective:To investigate the application of self-designed wound measuring grid in the measurement of wound and the design of perforator flap.Methods:From February 2018 to February 2020, 31 cases of soft tissue defects of limbs were repaired by free transfer of perforator flap. During the operation, the self-designed membrane with measurement grid was used to measure the wound surface. The flaps were designed and harvested according to the accurate measurement of the wound. The flaps were reviewed at hospital clinic during follow-up.Results:All patients entered 3-15 months of follow-up with an average of 8 months. All 31 flaps survived, of which 2 flaps encountered vascular crisis and were rescued after surgical exploration. There was no infection of flaps and all flaps had stage I healing. The flaps were satisfactory in appearance with the sensation recovery to S 2 in 21 cases and S 3 in 10 cases. Only linear scars were left on the donor sites. Conclusion:The membrane with a measurement grid can accurately measure a wound, and help the design of the flap according to the measured size and profile of the wound. It can reduce the operation time and the risk as well as to improve the operation efficiency. The clinical application is satisfactory. Large scale and multi-centre studies are required to further prove the benefit of the measurement grid.

Analysis of dosimetric verification results of three verification systems for stereotactic body radiation therapy / 中华放射医学与防护杂志

Objective:To compare the effects of parameters, such as planning target volume (PTV), calculation grid size, and dose threshold, on the dosimetric verification result of three dosimetric verification systems ArcCHECK, SRS MapCHECK, and 3DMap for stereotactic body radiation therapy (SBRT).Methods:Based on the dosimetric verification result of the SBRT plans of 50 patients, this study compared the effects of PTV (<25 cm 3 and ≥25 cm 3), calculation grid size (1.0, 1.5, and 2.0 mm), and dose threshold (5%, 10%, and 15%) on the γ passing rates of the three dosimetric verification systems at five criteria, i. e., 3 mm/3%, 3 mm/2%, 3 mm/1%, 2 mm/3%, and 2 mm/2%. Results:The changes in PTV affected 3DMap more significantly. With an increase in PTV, the γ passing rates of 3DMap at the criteria of 3 mm/3%, 3 mm/2%, 2 mm/3%, and 2 mm/2% increased by 2.2%, 2.2%, 4.4%, and 4.7% ( t=-2.76, -2.17, -4.72, -3.86, P<0.05), respectively. The increase in the calculation grid from 1.0 mm to 1.5 mm had greater effect on MapCHECK, with the γ passing rates at the criteria of 3 mm/3%, 3 mm/2%, 3 mm/1%, 2 mm/3% and 2 mm/2% decreased by 0.7%, 1.1%, 1.7%, 0.9%, 1.5% ( t=-6.15, -6.23, -5.98, -5.11, -8.34, P<0.05), respectively. The increases in the calculation grid from 1.0 mm to 2.0 mm had greater impact on ArcCHECK, with the γ passing rates at the criteria of 3 mm/3%, 3 mm/2%, 3 mm/1%, 2 mm/3%, 2 mm/2% decreased by 1.0%, 1.7%, 2.4%, 1.7%, 2.7% ( t=-4.75, -7.3, -8.63, -7.11, -8.26, P<0.05), respectively. The increase in the dose threshold from 5% to 10% had greater impact on ArcCHECK, with the γ passing rates at the criteria of 3 mm/3%, 3 mm/2%, 2 mm/3% and 2 mm/2% decreased by 1.1%, 1.4%, 2.5%, and 3.0% ( t=5.20, 5.68, 8.17, 9.99, P<0.05), respectively. Moreover, the increase in the dose threshold from 5% to 15% had more impact on 3DMap, with the γ passing rates at the criteria of 3 mm/3%, 3 mm/2%, 2 mm/3%, and 2 mm/2% decreased by 1.6%, 1.7%, 2.8%, and 3.2% ( t=3.25, 2.98, 4.40, 4.21, P<0.05), respectively. Conclusions:Target volume, calculation grid, and dose threshold are influencing factors in the dosimetric verification of three dosimetric verification systems for SBRT. Therefore, the effects of these parameters should be considered for different verification systems in clinical applications.

A spatial localization model of mobile robot based on entorhinal-hippocampal cognitive mechanism in rat brain / 生物医学工程学杂志

Physiological studies reveal that rats rely on multiple spatial cells for spatial navigation and memory. In this paper, we investigated the firing mechanism of spatial cells within the entorhinal-hippocampal structure of the rat brain and proposed a spatial localization model for mobile robot. Its characteristics were as follows: on the basis of the information transmission model from grid cells to place cells, the neural network model of place cells interaction was introduced to obtain the place cell plate with a single-peaked excitatory activity package. Then the solution to the robot's position was achieved by establishing a transformation relationship between the position of the excitatory activity package on the place cell plate and the robot's position in the physical environment. In this paper, simulation experiments and physical experiments were designed to verify the model. The experimental results showed that compared with RatSLAM and the model of grid cells to place cells, the positioning performance of the model in this paper was more accurate, and the cumulative error in the long-time path integration process of the robot was also smaller. The research results of this paper lay a foundation for the robot navigation method that mimics the cognitive mechanism of rat brain.

Quantitative Characterization of the Chemical Space Governed by Human Carbonic Anhydrases and selenium-containing derivatives of solfonamides

Abstract Due to the fact that different isoforms of carbonic anhydrase play distinct physiological roles, their diseases/disorders involvement are different as well. Involvement in major disorders such as glaucoma, epilepsy, Alzheimer's disease, obesity and cancers, have turned carbonic anhydrase into a popular case study in the field of rational drug design. Since carbonic anhydrases are highly similar with regard to their structures, selective inhibition of different isoforms has been a significant challenge. By applying a proteochemometrics approach, herein the chemical interaction space governed by acyl selenoureido benzensulfonamides and human carbonic anhydrases is explored. To assess the validity, robustness and predictivity power of the proteochemometrics model, a diverse set of validation methods was used. The final model is shown to provide valuable structural information that can be considered for new selective inhibitors design. Using the supplied information and to show the applicability of the constructed model, new compounds were designed. Monitoring of selectivity ratios of new designs shows very promising results with regard to their selectivity for a specific isoform of carbonic anhydrase.

Accessibility to primary health care in low-density regions. A case study: NUTS III - Baixo Alentejo - Portugal / A acessibilidade aos cuidados de saúde primários em regiões de baixa densidade. Caso de estudo: NUTS III - Baixo Alentejo - Portugal

Abstract This study diagnosed the situation regarding the physical accessibility of the resident population to primary health care, based on the characteristics of the population served, their spatial distribution in the territory, based on space-time analysis. Thus, bearing the different means of transport available and the specific features of a low-density territory, we considered several mobility profiles under analysis, and selected the Baixo Alentejo as the study area. In methodological terms, besides using the location of primary health facilities and their areas of influence, the use of the road network and its restrictions, we selected the use the new 1x1 km grid, recently implemented throughout the EU (European Union), instead of using the statistical units or administrative boundaries. Its advantages allow overcoming some of the issues of the usual base cartography. The final results can be divided into two groups: conclusions related to the methodologies used and conclusions related to the accessibility of primary health care equipment in the study area.

Resumo Decidiu-se realizar o diagnóstico de situação sobre a acessibilidade física da população residente aos cuidados de saúde primários, baseada nas características da população servida, na sua distribuição espacial, tendo por base uma análise espaço/tempo, permitindo avaliar essa mesma acessibilidade. Deste modo, e tendo em consideração os diversos modos de transporte disponíveis, bem como as características específicas de um território de baixa densidade, foram considerados diversos perfis de mobilidade, sendo a área de estudo escolhida o Baixo Alentejo. Em termos metodológicos, além da utilização da localização dos equipamentos de saúde primários e das suas áreas de influência, da utilização da rede viária e das suas restrições, optou-se pela utilização de uma cartografia base menos convencional. Em vez das unidades estatísticas associadas às unidades administrativas, optou-se pela utilização da nova quadrícula de 1x1 km, implementada recentemente em toda a União Europeia (UE). A utilização desta quadrícula permite ultrapassar alguns dos problemas apresentados pela cartografia base habitual. Os resultados podem-se dividir em dois grupos: conclusões relacionadas com as metodologias utilizadas, e conclusões relacionadas com a acessibilidade aos equipamentos de saúde primários na área de estudo.

Analysis of key issues and implementation strategies for grid management policy of the medical alliances / 中华医院管理杂志

Objective:To analyze the grid management strategy of medical alliances in Rizhao city, Shandong province, and to provide references for improvement of this policy.Methods:In August 2020, semi-structured interviews were conducted with 31 managers of three medical alliances in Rizhao city, regarding the objectives, specific measures, problems and influencing factors of the grid layout of the medical alliances. The grounded theory was used to sort out the interview data, along with the Mazmanian-Sabatier model for further analysis.Results:The analysis resulted in 8 main categories and 19 sub-categories, including theoretical and technical support, target group characteristics, policy causality theory, current status of policy directives, inter-agency relations, socioeconomic conditions and technology, public attitudes, and media campaigns. On this basis, a theoretical framework for the implementation of the grid layout of medical alliance was formed based on the Mazmanian-Sabatier model.Conclusions:The socio-economic conditions and technologies for implementing the grid-based management of medical alliances in Rizhao city were relatively mature, enjoying strong public support and good social response. But on the other hand, there were still such problems as unclear policies, imperfect mechanisms for synergy of interests among different subjects, and incomplete supporting policies. In the future, it is expected to form a policy implementation synergy, introduce supporting policies and strengthen primary teams building, in order to ensure the orderly promotion and long-term implementation of the policy.

Analysis of the technical feasibility of using artificial intelligence for smoothing active power in a photovoltaic system connected to the power system

Abstract Recent technological advances and increased participation of energy systems based on photovoltaic solar energy place this renewable energy source in a prominent position in the current scenario. With the increase in the share of solar photovoltaic systems, the impact of power fluctuations in these sources has worsened, which can affect the quality of electrical energy and the reliability of the electrical power system. Therefore, with the use of energy storage together with control algorithms based on artificial intelligence, it is possible to control and perform power smoothing. In this context, the study presents a technical feasibility study on the use of artificial neural network (ANN) to perform the power smoothing of the photovoltaic system connected to the network. Being studied the performance of a real photovoltaic system operating in conjunction with an ideal energy storage for comparative analysis of the performance of the artificial neural network when the numbers of neurons and layers are modified for different real operating conditions considered as temperature variation, humidity, irradiation, pressure and wind speed, which are considered to be ANN input data. The results obtained point to the feasibility of using ANN, with acceptable precision, for power smoothing. According to the analyzes carried out, it is clear that ANN's with few neurons, the smoothing profile tends to be more accurate when compared to larger amounts of neurons. In the current state of the study, it was not possible to determine a relationship between the variations in the number of neurons with the most accurate results, it is important to note that the development of the curve pointed by the neural network can be influenced by the database. It should be noted that, when ANN exceeds or does not reach the optimal smoothing curve, the storage system compensates for the lack or excess of power, and there is a need for other mechanisms to optimize power smoothing.

Curative effect of Triamcinolone acetonide combined with macular grid photocoagulation in the treatment of macular edema secondary to BRVO / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To analyze the efficacy and safety of triamcinolone acetonide(TA)combined with macular grid photocoagulation in the treatment of macular edema(ME)secondary to branch retinal vein occlusion(BRVO).<p>METHODS: A total of 147 patients(147 eyes)with ME secondary to BRVO treated in the hospital were enrolled between January 2016 and January 2020. They were randomly divided into observation group(73 eyes)and control group(74 eyes). The observation group was given intravitreal injection of TA and macular grid photocoagulation, while control group was given intravitreal injection of conbercept and macular grid photocoagulation. All were followed up for 6mo. Efficacy and safety indexes between the two groups were compared.<p>RESULTS:After treatment, best corrected visual acuity(BCVA, LogMAR)in both groups was improved. At 1mo after treatment, BCVA in observation group was better than that in control group(0.22±0.15 <i>vs </i>0.27±0.13, <i>P</i><0.05). At 6mo after treatment, BCVA of patients under 50 years in observation group was significantly better than that of patients under 50 years in control group(0.09±0.04 <i>vs </i> 0.14±0.06, <i>P</i><0.05).BCVA was the best in patients with type serous retinal detachment(SRD), followed by type ME and mixed type(<i>P</i><0.05). However, there was no significant difference in BCVA between any two groups in ME classifications(<i>P</i>>0.05). After treatment, central macular thickness(CMT)in both groups was significantly decreased. At 3mo after treatment, CMT in observation group was higher than that in control group(309.76±84.24μm <i>vs </i>258.75±88.76μm, <i>P</i><0.01). At 1wk, 1, 3 and 6mo after treatment, intraocular pressure in observation group was higher than that in control group(<i>P</i><0.01). At 6mo after treatment, blood flow density of superficial capillary plexus(SCP)in both groups was significantly higher than that before treatment(<i>P</i><0.05), but there was no significant change in blood flow density of deep capillary plexus(DCP)or the area of foveal avascular zone(FAZ)(<i>P</i>>0.05). The incidence of increased intraocular pressure was higher in observation group than control group(28.8% <i>vs </i>14.9%), and times of intravitreal injection were fewer than those in control group(1.21±0.74 times <i>vs </i>3.62±2.08 times).<p>CONCLUSION: TA combined with macular grid photocoagulation in the treatment of ME secondary to BRVO can maintain visual acuity at a certain level in the short term. The curative effect is comparable to that of conbercept combined with macular grid photocoagulation in terms of improving visual acuity and CMT. However, there is increased intraocular pressure, and the intraocular pressure monitoring needs to be strengthened.

Epidemic Characteristics of the Novel Coronavirus Delta Variant in Guangzhou and Grid Crowd Management Based on Public Security Forensic Perspective / 法医学杂志

Abstract： Objective To analyze the first epidemic spread of the novel coronavirus Delta variant in China based on public security forensic perspective, investigate its transmission characteristics, contributing factors, and epidemiologic research experience, and provide a reference for the prevention and control of the epidemic caused by the novel coronavirus variant. Methods Based on the information that public security forensic experts obtained from front-line epidemiologic research, the gender, age, place of residence, transmission route and infectivity of the coronavirus disease 2019 （COVID-19） confirmed cases, asymptomatic infected persons and their close contacts in Guangzhou caused by the novel coronavirus Delta variant were analyzed. The basic reproduction number （R0） during this epidemic in Guangzhou was calculated. Results Among the 153 cases infected with novel coronavirus Delta variant in the epidemic, 63 cases were male and 90 cases were female, their age ranging from 1 to 92 years, with a median age of 49 years. The main route of transmission was close contact, including dining together, co-living, and close contact in the same residential building. There were 31 cases of family clusters, 25 of which were in Liwan District. The epidemic lasted from May 26 to May 29, and the R0 remained above 4.0. After May 30, R0 began to decline and remained below 1.0 from June 7. Conclusion The novel coronavirus Delta variant is highly infectious, the crowd is generally susceptible to infection and family cluster cases are easy to occur. So, it is necessary to precisely prevent and control this strain. Public security forensic experts have both medical literacy and criminal investigation capabilities, they can play a more professional role in epidemic prevention and control.

Benefit Analysis of Grid Connected Photovoltaic Solar System with Energy Storage

Abstract The use of batteries combined with photovoltaic (PV) systems connected to the grid allows the storage of surplus energy from photovoltaic generation for later use. This combination can reduce dependence on the grid, since, for most consumers, peak consumption does not occur simultaneously with peak generation from the PV system. This article describes the initial operation of a PV system with 10.72kWp connected to grid and associated to a storage system with 57.6kWh lead-acid batteries installed at the Federal University of Technology - Paraná, in Curitiba city, Campus Neoville. We present an analysis of the benefits obtained from the combined use of the PV system connected to the grid with energy storage, reducing the total energy consumed from the grid. A brief analysis of the demand showed that, for this UTFPR campus, the peak power consumption occurred between 10:00 and 12:00 AM, which was also the interval of peak photovoltaic generation. We have observed that a scheduled battery discharge of 5.5% of the storage capacity from May to November and 9% discharge in December has resulted in R$ 1,154.44 of saving in the first seven months of operation.

Analysis of PV Systems Installed in Paraná

HIGHLIGHTS Comparative study of the operation of eight real cases of systems installed in Paraná. There is a convergence between the values estimated by the Atlas and the ones calculated. It was possible to identify the cities that presented the greatest figures of merit.

Abstract With the development of renewable energies in the world, there is also an increase in solar photovoltaic systems globally. In Brazil, and in the state of Paraná, there is an exponential growth of this form of energy generation, which causes the necessity to study the performance of the installed systems. Therefore, this article analyzed eight photovoltaic systems installed in the state of Paraná, under the aspect of figures of merit parameters, through calculations of final yield, performance ratio and capacity factor. In addition, the calculated values were compared to the values estimated by the Solar Energy Atlas of the State of Paraná. As a result, the largest average differences in final yield, between the calculations and the Atlas, were found in the cities of Cascavel, while the smallest were observed in Goioerê.

A spatial cognition model based on the selection mechanism of hippocampus place cells / 生物医学工程学杂志

Biological studies show that place cells are the main basis for rats to know their current location in space. Since grid cells are the main input source of place cells, a mapping model from grid cells to place cells needs to be constructed. To solve this problem, a neural network mapping model of back propagation error from grid cells to place cells is proposed in this paper, which can accurately express the location in a given region. According to the physiological characteristics of border cells' specific discharge to the environment, the periodic resetting of the grid field phase by border cells is realized, and the position recognition in any space is completed by this model. In this paper, we designed a simulation experiment to compare the activity of the theoretical place cell plate, and then compared the time consumption of the competitive neural network model and the positioning error of RatSLAM pose cells plate. The experimental results showed that the proposed model could obtain a single place field, and the algorithm efficiency was improved by 85.94% compared with the competitive neural network model in the time-consuming experiment. In the localization experiment, the mean localization error was 41.35% lower than that of RatSLAM pose cells plate. Therefore, the location cognition model proposed in this paper can not only realize the efficient transfer of information between grid cells and place cells, but also realize the accurate location of its own location in any spatial area.

Multivariate statistical analysis of Evans blue exudation spots and acupoint sensitization distribution in rats with acute intestinal mucosal injury / 针刺研究

OBJECTIVE: To observe the distribution characters of Evans Blue (EB) exudation spots in the abdominal area in acute intestinal mucosal injury (AIMI) rats by using latitude and longitude grid counting and multivariate statistical analysis and to explore the feasibility of these methods. METHODS: Twenty-four SD rats were randomly divided into blank control, 7.5%, 10%, and 12.5% mustard oil groups (n＝6 rats in each group). The AIMI model was established by mustard oil enema, followed by injection of EB (0.1 mL/100g) into the tail vein. At 5, 10, 15, 20 and 25 h after EB injection, the rats under anesthesia were fixed in supine position for observing and photographing the abdominal subcutaneous EB exudation spots. The H．E. staining was used to observe histopathological changes of colonic mucosa. The longitude and latitude grids of the abdominal region were constructed (by taking the midpoint of the superior sternum as the origin) to determine the position of the blue spots. That the coordinate grids of the two regions can be connected geometrically is termed as "characteristic region". The data were processed by using multivariate statistical analysis. RESULTS: ① H．E. staining showed edema and inflammatory cell infiltration after colonic enema of different concentrations of mustard oil. ② Clustering analysis indicated that the distribution of exudation points in the "characteristic grid" had no temporal variation trend, and was not related with the concentration of mustard oil (P>0.05). ③ Factor analysis and contour analysis about the exudation spots of EB at 7.5% concentration showed that the "characteristic region Ⅱ" of different factors presented a tendency of time-dependent exudation, i．e. reduction of exudation degree along with time (P<0.05), and it is located near "Tianshu" acupoint. ④At 5 h after injection of EB, the 8 "characteristic regions" presented an EB-concentration-dependent tendency (reduction in exudation degree along with the increase of EB-concentration), among which the exudation degree of region C (near "Tianshu" acupoint) of the abdomen was higher (P<0.05). CONCLUSION: The multivariate statistical analysis method can be used to identify the abdominal "characteristic regions" of exudation spots of EB in rats with AIMI, and the characteristic region has acupoint sensitization characteristics related to the time and severity of mucosal injury.

Efficacy of intravitreal injection of Ranibizumab combined with macular grid photocoagulation for diabetic macular edema / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To evaluate the efficacy of intravitreal injection of ranibizumab combined with macular grid photocoagulation for diabetic macular edema. <p>METHODS: In this prospective cohort study, total 78 patients(101 eyes)diagnosed with diabetic macular edema in Dongguan People's Hospital from October 2016 to December 2018 were randomly divided into two groups. 40 patients(52 eyes)were in combination therapy group and 38 patients(49 eyes)were in monotherapy group. The changes of best corrected visual acuity(BCVA), central retinal thickness(CRT)and frequency of injections in two groups were compared after 12mo follow-up.<p>RESULTS: At the end of 12mo follow up, the BCVA(0.44±0.22 <i>vs</i> 0.55±0.23)and CRT(335.3±65.9μm <i>vs</i> 370.4±84.4μm; <i>P</i><0.05)were better in combination therapy group than that in monotherapy group. Fewer injections were required in combination therapy group compared with that in the monotherapy group(4.04±1.08 <i>vs</i> 5.83±1.92 injections, <i>t</i>= -5.722, <i>P</i><0.05). There was no significant difference between two groups(13.87±2.55 <i>vs</i> 14.04±2.69mmHg, <i>P</i>>0.05)in intraocular pressure. <p>CONCLUSION: Combination therapy of ranibizumab and macular grid photocoagulation was an effective treatment for DME patients, could significantly reduced the frequency of injections, and represent a superior therapeutic approach to DME patients.