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This paper presents a single-lever control method based on Power Management System (PMS) and improved Twin Delayed Deep Deterministic Policy Gradient (TD3) algorithm for turboprop engines. In this approach, power level angle command, which is the single-lever command, is decoupled into controlled variable commands by PMS, and the controller based on improved TD3 algorithm can ensure that controlled variables track their commands rapidly and accurately. To achieve the optimal conversion relationship between different commands, an offline optimization process is used to design PMS. By optimization, specific fuel consumption and propeller efficiency are both improved after conversion. To deal with strong interactions between different control loops of a turboprop engine, TD3 algorithm which is a deep reinforcement learning algorithm is adopted. Two improvements which are the design method of observation state and prioritized experience replay are made to enhance the tracking accuracy. Simulation results show that improved TD3 algorithm can learn an optimal control policy to guarantee good control effect with fast response and small overshoot. The maximum settling time is less than 0.25s and the maximum overshoot is less than 0.1%. It also has a good robustness performance when the plant exists model uncertainties. The maximum fluctuations are less than 0.05%. [ABSTRACT FROM AUTHOR]

Negative air ion (NAI) concentration is an important indicator comprehensively reflecting air quality, and has significance to human beings living environment. This paper summarized the spatiotemporal distribution features of urban NAI concentration, and discussed the causes of these features based on the characteristics of the environmental factors in urban area and their effects on the physical and chemical processes of NAI. The temporal distribution of NAI concentration is mainly controlled by the periodic variation of solar radiation, while the spatial distribution of NAI concentration along the urban-rural gradient is mainly affected by the urban aerosol distribution, underlying surface characters, and urban heat island effect. The high NAI concentration in urban green area is related to the vegetation life activities and soil radiation, while the higher NAI concentration near the water environment is attributed to the water molecules that participate in the generation of NAI through a variety of ways. The other environmental factors can also affect the generation, life span, component, translocation, and distribution of NAI to some extent. To increase the urban green space and atmospheric humidity and to maintain the soil natural attributes of underlying surface could be the effective ways to increase the urban NAI concentration and improve the urban air quality. [ABSTRACT FROM AUTHOR]

Negative air ion (NAI) concentration is an important indicator comprehensively reflecting air quality, and has significance to human beings living environment. This paper summarized the spatiotemporal distribution features of urban NAI concentration, and discussed the causes of these features based on the characteristics of the environmental factors in urban area and their effects on the physical and chemical processes of NAI. The temporal distribution of NAI concentration is mainly controlled by the periodic variation of solar radiation, while the spatial distribution of NAI concentration along the urban-rural gradient is mainly affected by the urban aerosol distribution, underlying surface characters, and urban heat island effect. The high NAI concentration in urban green area is related to the vegetation life activities and soil radiation, while the higher NAI concentration near the water environment is attributed to the water molecules that participate in the generation of NAI through a variety of ways. The other environmental factors can also affect the generation, life span, component, translocation, and distribution of NAI to some extent. To increase the urban green space and atmospheric humidity and to maintain the soil natural attributes of underlying surface could be the effective ways to increase the urban NAI concentration and improve the urban air quality.

Objective: To investigate the effects of transurethral resection of the prostate (TURP) on lower urinary tract symptoms (LUTS) in patients with benign prostatic hyperplasia (BPH) complicated by histological prostatitis., Methods: This study included 432 cases of BPH pathologically confirmed after TURP. Excluding those with LUTS-related factors before and after surgery and based on the international prostatitis histological classification of diagnostic criteria, the remaining 144 cases were divided into groups A (pure BPH, n = 30), B (mild inflammation, n = 55), C (moderate inflammation, n = 31), and D (severe inflammation, n = 28). Each group was evaluated for LUTS by IPSS before and a month after surgery., Results: A total of 399 cases (92.4%) were diagnosed as BPH with histological prostatitis, 269 (67.4%) mild, 86 (21.6%) moderate and 44 (11.0%) severe. The preoperative IPSS was 21.43 +/- 6.09 in group A, 21.75 +/- 5.97 in B, 27.84 +/- 4.18 in C and 31.00 +/- 2.92 in D, with statistically significant differences among different groups (P < 0.001) except between A and B (P = 1.000); the postoperative IPSS was 5.60 +/- 2.16 in A, 7.36 +/- 2.77 in B, 11.55 +/- 3.39 in C and 16.89 +/- 3.37 in D, with statistically significant differences among different groups (P < 0.01), and remarkably lower than the preoperative one (P < 0.001). Almost all the infiltrating inflammatory cells in BPH with histological prostatitis were lymphocytes., Conclusion: BPH is mostly complicated with histological chronic prostatitis. The severity of LUTS is higher in BPH patients with histological prostatitis than in those without before and after TURP, and positively correlated with the grade of inflammation. Those complicated with moderate or severe histological prostatitis should take medication for the management of LUTS.

Objective: To investigate re-innervation in the neovaginal mucosa of patients underwent sigmoid colon vaginoplasty in treatment of Mayer-Rokitansky-Kistner-Hauser Syndrome (MRKHS)., Methods: Biopsies in the upper third of the posterior neovagina were taken in 20 patients treated by sigmoid colon vaginoplasty at 1, 2 and 3 years after surgery, respectively. Protein gene product 9.5 (PGP 9.5), vasoactive intestinal peptide (VIP) and neuropeptide Y (NPY) were detected by immunohistochemical method and compared with those in intact sigmoid colon mucosa., Results: (1) Density of nerve fiber: abundant distribution of PGP 9.5 nerve fibers were observed in the mucosal muscle layer, submucosa, and smooth muscle layer of the neovagina. The nerve fibers of VIP and NPY immunoreactivity were mainly distributed around blood vessels and in the smooth muscles. In the neovagina, the density of nerve fibers of PGP 9.5 of 17 ± 6 were much more than VIP of 2.9 ± 1.0 and NPY of 2.5 ± 0.8 significantly (P < 0.05). (2) Expression of PGP 9.5 in neovagina: at 1 year after surgery, PGP 9.5 positive expression of 14 ± 4 was significantly lower in the neovagina than 28 ± 7 in the intact sigmoid colon (P < 0.05). However, after 2 to 3 years, its expression displayed an upgrade tendency in the neovagina and was significantly higher at the 3 year postoperatively than that at the 1 years postoperatively (22 ± 7 vs. 14 ± 4, P < 0.05). The changes were much more obvious in submucosa. (3) The expression of VIP and NPY in neovagina: at 1 year after surgery, VIP and NPY positive nerve fibers were also decreased in the neovagina when compared with those in the intact sigmoid colon (2.3 ± 0.7 vs. 5.3 ± 1.4, P < 0.05; 2.5 ± 1.1 vs. 5.5 ± 1.1, P < 0.05). At 2 to 3 years after surgery, the positive VIP fiber showed initially decreased and subsequently increased tendency. The density of VIP of 3.7 ± 0.7 in the neovagina at 3 years postoperatively was higher than 2.3 ± 0.7 at 1 years postoperatively (P < 0.05). No significant up-regulation was observed in NPY-positive expression in the neovagina within 3 years after operation., Conclusions: Distribution of sensory PGP 9.5, VIP and NPY immunoreactive nerve fibers was similar to the pattern observed within the intact sigmoid colon wall. The number of nerve fibers in the neovagina decreased after surgery and then increased subsequently within 3 years after surgery.

Objective: In order to evaluate the changes of neovaginal defense function in the sight of physical barrier by investigating the changes in the histological morphology and expression of occludin, zona occluden-1 (ZO-1) in mucosal cells of the neovagina in patients undergoing vaginal construction by sigmoid colon., Methods: Fifteen cases with neovagina constructed by sigmoid colon matched with 15 cases' vaginal mocusa as control specimens were observed with light microscopic and electron microscopic methods. At the same time, the expression of occludin and ZO-1 were semiquantitatively measured by streptavidin-perosidase (SP) immunohistochemical method., Results: (1) Squamous metaplasia was observed in colonic mucosa from lower one-third of the artificial vagina in 10 cases (67%, 10/15). (2) The intercellular tight junctions of neovaginal mucosa became shorter and wider, the number of them were decreased or disappeared by electron microscopic study. (3) In upper neovagina, the positive rates of occludin and ZO-1 expression in mucosal cells were 80% (12/15) and 73% (11/15), respectively. In lower neovaginal mucosa where squamous metaplasia occurred, the positive rates of two protein expression in cells were both 100% (10/10) and also was 100% (15/15) in control group, which showed significant difference (P < 0.05, P < 0.01). In lower neovaginal mucosa where squamous metaplasia hadn't occurred, the positive expression of two protein in cells (4/5, 2/5) were significantly lower than those in lower neovaginal mucosa where squamous metaplasia had happened 100% (10/10), 100% (10/10) and in control group [100% (15/15), 100% (15/15)] (P < 0.05), while there were no significantly difference in positive expression of two protein in cells between this group and upper neovagina (P > 0.05)., Conclusions: The squamous metaplasia had occurred in lower neovaginal mucosa. The decreased expression of occludin and ZO-1 in upper and lower neovaginal mucosa where squamous metaplasia didn't occurred. However, In lower neovaginal mucosa where squamous metaplasia occurred, the expression of occludin and ZO-1 in cells were similar to those in control group, which might play a role in the defense function of neovaginal mucosa.

Objective: To study the changes of the histology and expression of neuronal nitric oxide synthase (nNOS) in the neovaginal mucosa of the patients undergoing vaginal construction with sigmoid colon., Methods: Biopsy samples of upper one-third and lower one-third of the artificial vagina were obtained from 14 patients who underwent vaginal construction with sigmoid colon 9 - 48 months before and samples of normal sigmoid colon were collected from another 14 patients during vaginal construction with sigmoid colon as control group. The pathological and ultrastructural changes were comparatively observed by light microscopy and electron microscopy. At the same time, the expression of nNOS was semiquantitatively evaluated with immunohistochemical method., Results: The upper one-third of the artificial vagina muscular layer of mucosa was hyperplastic and hypertrophic and the density of the submucosal nerve plexus was 3.6 +/- 1.5, significantly higher than that of the control group (1.7 +/- 0.8, P < 0.05). Squamous metaplasia was seen in the colonic mucosa from some 3 samples of lower one-third of the artificial vagina. Partial fusion of the intercellular tight junction, disappearance and fusion of mitochondrial cristae, and degranulation of rough endoplasmic reticulum could be seen in the vaginal colonic mucosa. Compared with the normal control, the expression of nNOS in the vaginal colonic mucosa was significantly decreased., Conclusion: Morphologic changes occur nNOS expression decreases in the colonic mucosa of the artificial vagina.

Objective: To study the histogenesis and the putative mechanisms of adenocarcinoma induced by AFG1 and ST in NIH mice., Methods: Thirty-four cases of lung adenocarcinomas induced by AFG1 and ST in NIH mice were included in this study and 12 cases of normal lung tissues were used as control. The phenotype of the lung adenocarcinomas was determined by immunohistochemical expression of SP-C and CC-10 at protein level. The expression of P53, Ras P21 and PCNA was studied with immunohistochemical staining., Result: The positive expression of SP-C was found in all the lung adenocarcinomas, while no expression of CC-10 could be seen. The labelling index of PCNA in the adenocarcinomas were significantly higher than that of control (P < 0.01). No positive expression of mutant P53 and Ras at protein level could be found., Conclusion: The lung adenocarcinomas induced by the two mycotoxins in NIH mice arise from alveolar type II cells and no expression of mutant P53 and Ras at protein level was found in the lung adenocarcinomas.

Objective: To further explore the carcinogenic activity of Sterigmatocystin (ST) and the possible synergistic carcinogenic effect of deoxynivalenol (DON) in NIH mice., Methods: NIH mice were randomly divided into 6 groups, 30 in each. Five groups of mice were given by gastric intubation ST 3 microg/kg, ST 30 microg/kg, ST 3 microg/kg + DON 1.5 microg/kg, ST 30 microg/kg + DON 1.5 microg/kg and DON 1.5 microg/kg respectively, 3 times a week for 24 weeks. The remaining group of mice was given normal saline accordingly, serving as control. All mice were fed with HPLC-confirmed mycotoxin-free food, analysis. The mice were killed and pathologically examined at 58th and 74th weeks., Results: No pathological changes were found in the control group of mice. Adenocarcinoma of lung was observed in 25.0%, 41.7%, 62.5%, 69.2% and 37.5% of mice given ST 3 microg/kg, ST 30 microg/kg, ST 3 microg/kg + DON 1.5 microg/kg, ST 30 microg/kg + DON 1.5 microg/kg and DON 1.5 microg/kg, respectively. In addition, dysplasia of glandular stomach was detected in 50.0%, 58.3%, 37.5%, 53.8% and 25.0% of mice similarly treated., Conclusion: Oral administration of ST or DON can induce adenocarcinoma in lung and dysplasia of glandular stomach in NIH mice. There is synergistic carcinogenic effect when both ST and DON are given.

Objective: Aflatoxin G1 (AFG1) is a member of the carcinogenic aflatoxin family produced by aspergillus flavus. It is a major contaminating mycotoxin in food in areas of China with high cancer incidence. The purpose of this study is to explore the carcinogenic effects of AFG1 in NIH mice., Methods: NIH mice were randomly divided into three groups. Two experimental groups were treated intragastrically by gavage with AFG1 3 microg/kg and AFG1 30 microg/kg respectively, 3 times a week for 24 weeks. The control group was treated with normal saline. All mice were fed with food that was free of AFGs as confirmed by HPLC analysis. The mice were weighed every week throughout the entire experiment, and then sacrificed and examined pathologically at the 58th and 74th weeks respectively., Results: Compared with control mice receiving no AFG1, bronchial epithelial hyperplasia, alveolar hyperplasia and adenocarcinoma of lung were observed in mice receiving AFG1 treatment. The incidences of bronchial epithelial hyperplasia, alveolar hyperplasia and adenocarcinoma of lung were 60.0%, 10.0% and 30.0% for mice receiving 3 microg/kg AFG1 and 28.6%, 35.7%, 42.9% for mice receiving 30 microg/kg of the toxin, respectively., Conclusion: Oral administration of AFG1 can induce hyperplastic lesions and adenocarcinoma of lung in NIH mice.