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Porosity is a key parameter that affects the heat and moisture transfer within a grain pile. In order to investigate the distribution law of porosity in bulk grain piles in grain silos, grain compression experiment was carried out to obtain the porosity of different grain types under different moisture content and vertical pressure conditions. A porosity prediction model for grain cell based on GWO-BP neural network was proposed, and the model was compared with the porosity prediction results of BP neural network model and random forest model. Finally, the generalization ability of the model was verified using the grain cell box test. The results showed that the porosity prediction performance of the GWO-BP neural network model was the best, and the evaluation indexes of the model, including R2 of 0.960 5, RMSE of 0.013 7 and MAE of 0.013 1, were all within the permissible range. This study has provided a neural network prediction method for the determination of grain porosity, which could provide an important foundation for in-depth multi-field coupling analysis of grain piles and theoretical support for safe grain storage.

Objective: In order to solve the quality problems of YB517 transparent packaging machine, such as folds and unevenness of transparent paper on the sides of cigarette packages, a new cigarette-packaging side seal and shaping device was developed. Methods: After the improvements, the drive shaft of cigarette receiving plate of output turntable of YB517 was used as a power source, and the heating and shaping of cigarette package side seals were achieved by designing reciprocating mechanisms, heater components, cigarette package positioning components, and optimizing push seats; and using Solidworks software to simulate and analyze the displacement, velocity and acceleration of the shaping device. At the same time, it was connected to the temperature measurement and control system of "Heat sealer for Drawstring" so that the temperature parameters can be displayed and adjusted on the IPC control surface. Finally, the method of sampling in the test was used to compare and analyze the wrinkle of boxed transparent paper before and after the transformation. Results: The side seal shaping device had the advantages of no interference, gentle velocity and acceleration curve, no obvious impact and stable operation. The wrinkle ratio of boxed transparent paper decreased from 11.58% to 2.50%, which decreased 78.40%. Conclusion: It ensures product quality and improves consumers satisfaction.

ObjectiveTo evaluate the effects of different pretreatment methods and preservation time on RNA quality of peripheral blood samples, and to optimize the preservation method of peripheral blood samples.MethodsEight pretreatment methods were used to preprocess the peripheral blood from 3 healthy unrelated individuals and the treated samples were stored at -80 ℃. Total RNA of samples was extracted using Quick-RNATM Miniprep Plus kit. DNA/RNA ShieldTM was added to peripheral blood and total RNA was extracted after preservation at -80 ℃ for 0, 5, 10, 15, 30 and 60 days, respectively. The concentration, purity and integrity of RNA were determined. Statistical analyses were performed by SPSS 22.0 software to compare the differences in RNA yield, purity and integrity among the eight pretreatment methods.ResultsIn terms of purity, leukocyte pretreated with RNAlaterTM and directly cryopreservation peripheral blood showed the worst purity. The other six methods showed better purity. In terms of yield, blood cells with DNA/RNA ShieldTM came out with the highest yield, followed by peripheral blood with DNA/RNA ShieldTM. In terms of integrity, peripheral blood preserved in PAXgene Blood RNA tube method had the best integrity. Except for peripheral blood pretreated with DNA/RNA ShieldTM and blood cells pretreated with DNA/RNA shieldTM, the other five methods had statistical differences when compared to the method by keeping peripheral blood in PAXgene Blood RNA tube. The purity of RNA stored at six-time gradients ranged from 1.815 to 1.952. With the increase of storage time, RNA yield decreased from 4.516 ng to 1.039 ng, and RNA integrity decreased from 8.533 to 7.150.ConclusionAccording to the results of total RNA’s yield, purity and integrity, peripheral blood pretreated with DNA/RNA ShieldTM was the best pretreatment method. After the pretreatment, samples can be preserved for up to 60 days in low temperature.

In the process of hard cutting die steel Crl2MoV, the workpiece material hardness is very high, so the tool endure severely thermo mechanical coupling effects. Tool wear mechanism is different from the traditional cutting process. Based on the PCBN tool precision cutting process of die steel Crl2MoV, in this paper the tool rake face wear and the flank face wear form are studied, and tool wear mechanisms in different positions through elements change analysis is researched. Under different cutting speeds and feeds tool wear research regularity results provide theoretical basis for reasonable selection of cutting conditions. The research results reveal that cutting force is affected by mechanism of cutting tool wear. Different tool wear amount of geometric model are founded by using UG software, different cutting FEM models are founded to research effect of tool wear on cutting temperature by u-sing Deform software in this paper. [ABSTRACT FROM AUTHOR]

Recently, researches on copy number variation （CNV） have extended to every field, such as etiological exploration and precise treatment of complex diseases, as well as genetic breeding and evolution. The unique genetic characteristics of CNV have made people gradually believe that it could be used as a biological genetic marker to solve related problems. With the development of detection technology, application of CNV in forensic medicine will increase gradually. In this paper, the concept and development of CNV, as well as its application in forensic medicine are summarized, to provide new ideas for the practical application of CNV in the future.

Objective: To observe the effect of electroacupuncture (EA) of "Weizhong" (BL40) on the expression of platelet-derived growth factor (PDGF)-CC, PDGF receptor (PDGFR)α and matrix metalloproteinase-1 (MMP-1) in rats with lumbar multifidus muscle injury (LMMI) so as to study its mechanisms underlying improvement of skeletal muscle injury., Methods: Fifty-four male SD rats were randomly divided into normal group ( n =6), model group ( n =24) and EA group ( n =24), and the latter two groups were further divided into four subgroups (1, 3, 5 and 7 days), with 6 rats in each group. The LMMI model was established by injection of 0.5% bupivacaine (BPVC, 100 μL×4) into the multifidus along the L4 and L5 spinous process. EA (2 Hz/50 Hz, 1 mA) was applied to bilateral "Weizhong"(BL40) for 20 min, once daily for 1, 3, 5 and 7 days respectively, from the first day on after modeling. Histopathological changes of the left multifidus muscle were observed after H.E. staining, and the expression of PDGF-CC, PDGFR-α and MMP-1 proteins in the right multifidus was observed by Western blot., Results: Compared with the normal group, the expression levels of PDGF-CC protein in the model subgroup 1 d, 3 d and 7 d were significantly decreased ( P <0.05), and those of PDGFR-α and MMP-1 proteins in the model subgroup 5 d and 7 d, and PDGF-CC protein in the model subgroup 5 d significantly increased ( P <0.05). In comparison with the model subgroups, the expression levels of PDGF-CC in the EA subgroup 3 d, 5 d and 7 d, PDGFR-α in the EA subgroup 5 d, and MMP-1 in the EA group 3 d and 5 d were significantly increased or significantly further increased ( P <0.05). H.E. staining showed different shapes and uneven sizes, with large area of damage, enlarged muscle space and inflammatory cell infiltration in the model group, which was relatively milder in the EA subgroups particularly in subgroup 5 d and 7 d., Conclusion: EA stimulation of BL40 for about 5 days has a positive effect in promoting the repair of the injured multifidus muscle in LMMI rats, which may be related to its function in up-regulating the expression of muscular PDGF-CC, PDGFR-α and MMP-1 proteins.

We monitored the type and content of airborne pollen in Haidian District, Beijing City from 2012 to 2016 by the gravity precipitation method, and analyzed the variety of pollen, peak distribution features and changes of its content, and discontinuous variation of concentration. Multiple time scale analysis was carried out for pollen concentration by the ensemble empirical mode decomposition method (EEMD). The relationship between pollen concentration and meteorological factors was analyzed. The results indicated that during the research period, the main types of airborne pollen changed. Woody plants such as Cupressaceae and Salicaceae instead of herbaceous plants contributed the most content of pollen. There was no significant change of the yearly peak distribution of pollen concentration. The concentration in recent five years reduced, while the concentration of herbaceous plants (such as Scolopacjdae) increased. During the statistics period, pollen concentration showed discontinuous changes in early April, late May and early August. Pollen concentration had the change cycle of quasi 2 d, quasi 51 d and quasi 128 d. Among all meteorological factors, temperature played a dominant role in driving the concentration, which may significantly rise during 16 to 18 ℃. The impact of temperature changes on the daily concentration may be delayed and continuous; it is often highly related to the concentration 2-7 d later. Sunshine duration and wind speed had the most significant impact on daily pollen concentration.

Objective: To assess the effect of corporoplasty with autologous tunica vaginalis graft in the treatment of Peyronie's disease., Methods: Ten patients with Peyronie's disease underwent plaque excision and corporoplasty with autologous tunica vaginalis graft. We obtained and compared IIEF-5 scores of the patients before and at 1 and 5 years after operation., Results: After surgery, penile curvature was obviously relieved and all the patients achieved normal penile erection and satisfactory sexual intercourse without erection-related pain or recurrent erectile dysfunction. The mean IIEF-5 score was significantly improved at 1 year (22.40±1.08) and 5 years postoperatively (23.00±1.14) as compared with the baseline, (19.20±2.28) (P<0.05 or 0.01)., Conclusions: Corporoplasty with autologous tunica vaginalis graft is a safe, simple and effective option for the treatment of Peyronie's disease, though its definite efficiency is to be further supported by large-sample clinical studies.

Objective: To investigate the factors influencing the prognosis of penis-sparing surgery (PSS) for early-stage penile cancer., Methods: We retrospectively studied the clinical data about 45 cases of early-stage penile cancer treated by PSS from January 2007 to December 2014. We calculated the rate of local recurrence-free survival by the Kaplan-Meier method, and conducted univariate and multivariate COX regression analyses on the relevant factors including the patient's age, marital status, tumor location, tumor size, postoperative sexual life, histological grade, and TNM stage., Results: One-year and three-year local recurrence-free survival rates were 95.5% and 52.2%, respectively. Multivariate analysis demonstrated that the histological grade (P = 0.039) and postoperative sexual life (P = 0.049) were independent factors for the prognosis of PSS. Logistic regression showed the patients age to be significantly associated with histological grade (P = 0.014)., Conclusion: Histological grade and postoperative sexual life are important independent prognostic factors of PSS for early-stage penile cancer, and the patients age is associated with the prognosis of PSS through its influence on the tumor grade.

Objective: To investigate the correlation of the deleted azoospermia (DAZ) gene copy related to gr/gr and b2/b3 deletions in the AZFc region with male spermatogenic impairment., Methods: This study included 121 infertile men with different de- grees of spermatogenic impairment and 95 healthy donors from the sperm bank. Using PCR, PCR-RFLP, and Y chromosome specific sequence tagged sites (STS) , we analyzed the association of DAZ gene copy deletions related to gr/gr and b2/b3 deletions in the AZFc region with spermatogenic impairment., Results: There were 15 cases of gr/gr deletion (12. 40% ) and 6 cases of b2/b3 deletion (4.96%) in the infertility group as compared with 13 cases of gr/gr deletion (13.68%) and 1 case of b2/b3 deletion (1.05%) in the control. Analysis of the DAZ-specific single nucleotide variant (SNV) loci revealed 11 gr/gr-DAZI/DAZ2 deletions (9.09%), 4 gr/gr-DAZ3/DAZ4 deletions (3.31%), and 6 b2/b3-DAZ1/DAZ2 deletions (4.96%) in the infertile men in comparison with 3 gr/ gr-DAZ1/DAZ2 deletions (3.16%), 10 gr/gr-DAZ3/DAZ4 deletions (10.53%), and 1 b2/b3- DAZ3/DAZ4 deletion (1.05%) in the control., Conclusion: Partial deletions of gr/gr and b2/b3 exist in both healthy men and male patients with different degrees of spermatogenic impairment and cannot be considered as a risk factor for spermatogenesis impairment. However, deletions of different DAZ duplicons in gr/gr and b2/b3 deletions have different effects on spermatogenesis. DAZ1/DAZ2 instead of DAZ3/DAZ4 deletions might be associated with spermatogenesis impairment.

Objective: To investigate the expressions and action mechanisms of nerve growth factor (NGF) receptors TrkA and p75NTR in the oncogenesis and progression of prostate cancer (PCa)., Methods: Using immunohistochemistry, we detected the expressions of TrkA and p75NTR in 62 PCa and 35 benign prostatic hyperplasia (BPH) samples, and conducted statistical analysis on the basis of clinical data., Results: Independent-samples t-test showed that, along with poorer tissue differentiation or higher clinical stage of PCa, the expression of TrkA was significantly up-regulated, that of p75NTR remarkably down-regulated, and the expression ratio of TrkA to p75NTR markedly increased. The TrkA/p75NTR ratio was 0.32 in the BPH, 0.52 in the PCa tissue with Gleason score of 6, 1.65 in the PCa tissue with Gleason score of 7, 5.75 in the PCa tissue with Gleason score ≥ 8, 0.89 in the clinical stage of pT2, 1.5 in pT3 a, 3.75 in pT3b, and 7.00 in pTxN1., Conclusion: The abnormally increased expression ratio of TrkA to p75NTR might be one of the essential features of malignant transformation of prostate cells. A higher TrkA/p75NTR expression ratio may be associated with a lower tissue differentiation, a higher clinical stage or Gleason score, and therefore a poorer prognosis.

Prostate cancer (PCa) is one of the most common malignant tumors as well as a frequent cause of cancer-related mortality in men worldwide. The test of serum markers has dramatically improved the early diagnosis of PCa, but its underlying molecular mechanisms are not yet completely identified. Long noncoding RNA (IncRNA) is emerging as a new player in the PCa paradigm demonstrating its potential roles in both oncogenic and tumor suppressive pathways. LncRNA is frequently aberrantly expressed in the majority of PCa cases. This review highlights recent findings of the aberrant expression of lncRNA in PCa and discusses its novel roles in the diagnosis, prediction, prognosis, metastasis, and potential clinical treatment of PCa.

MicroRNAs are a kind of small non-coding single-stranded RNA molecules that negatively regulate the gene expression by binding to imperfect complementary sites in the 3' untranslated region of targeted mRNAs at the post-transcriptional level. Aberrant expressions of some miRNAs like miR-221/222, miR-146a and miR-125b have been found to be significantly associated with androgen-independent progression of prostate cancer. By analyzing the aberrant expressions and regulation mechanisms of miRNAs in cell lines, tissues and peripheral blood samples, we hope to provide a new theoretic base for the clinical diagnosis and treatment of androgen-independent prostate cancer.

MicroRNAs (miRNAs) are a kind of small non-coding single-stranded RNA molecules that negatively regulate gene expressions by binding to imperfect complementary sites in the 3 untranslated region of targeted mRNAs at the post-transcriptional level. The aberrant expression of some miRNAs has been discovered to be involved in the pathogenesis of various cancers, including prostate cancer. By analyzing miRNA expressions in prostate cancer tissues, serum and cell lines, and then investigating their mechanisms, we expect to provide some new theoretic bases for the clinical diagnosis and treatment of prostate cancer.