A machine learning model for predicting the ballistic impact resistance of unidirectional fiber-reinforced composite plate

It has been a vital issue to ensure both the accuracy and efficiency of computational models for analyzing the ballistic impact response of fiber-reinforced composite plates (FRCP). In this paper, a machine learning (ML) model is established in an effort to bridge the ballistic impact protective performance and the characteristics of microstructure for unidirectional FRCP (UD-FRCP), where the microstructure of the UD-FRCP is characterized by the two-point correlation function. The results showed that the ML model, after trained by 175 cases, could reasonably predict the ballistic impact energy absorption of the UD-FRCP with a maximum error of 13%, indicating that the model can ensure both computational accuracy and efficiency. Besides, the model's critical parameter sensitivities are investigated, and three typical ML algorithms are analyzed, showing that the gradient boosting regression algorithm has the highest accuracy among these algorithms for the ballistic impact problem of UD-FRCP. The study proposes an effective solution for the traditional difficulty of the ballistic impact simulation of composites with both high efficiency and accuracy.

[Clinical effects of vacuum sealing drainage in the treatment of alkali burn wounds]

Objective: To preliminarily observe the clinical effects of vacuum sealing drainage (VSD) in the treatment of alkali burn wounds. Methods: From June 2016 to March 2020, 60 male patients with alkali burns who met the inclusion criteria and hospitalized in the Affiliated Hospital of Jiangnan University were recruited in this prospectively randomized control study. According to the random number table, silver sulfadiazine group and VSD group were both allocated with 30 patients, aged (36±8) and (35±10) years respectively; with total burn area of (7.2±2.0) % and (8.5±3.0) % total body surface area respectively. After admission, patients in silver sulfadiazine group were treated with conventional silver sulfadiazine dressing change once a day after debridement; patients in VSD group were given continuous VSD treatment after debridement, with the negative pressure setting at -10.67 kPa, and the negative pressure materials were replaced every 6 to 8 days. On treatment day 1, 4, and 7, the exudate from the wounds of patients in silver sulfadiazine group and the wound drainage fluid of patients in VSD group were collected, the pH value was measured by a portable pH meter, and the volume of exudate/drainage fluid was measured. After 7, 14, and 21 days of treatment, the wound healing rates of patients were calculated in the two groups. Before treatment and 7 days after treatment, venous blood was collected from the patients in the two groups to detect the serum level of tumor necrosis factor α (TNF-α) and interleukin 8 (IL-8). Within treatment day 14, Visual Analogue Scale was used to assess the pain score of patients in the two groups during each time of dressing change. The medical costs and discharge satisfaction scores of patients in the two groups were recorded. Data were statistically analyzed with analysis of variance for repeated measurement, t test, and Bonferroni correction. Results: (1) On treatment day 1, 4, and 7, the pH values of the drainage fluid of patients in VSD group were 9.75±0.59, 9.01±0.46, and 8.13±0.28, respectively, which were significantly higher than 9.35±0.62, 8.18±0.18, and 7.58±0.09 of exudate of patients in silver sulfadiazine group (t=2.03, 6.80, 7.56, P<0.05 or P<0.01). On treatment day 1 and 4, the volumes of drainage fluid of patients in VSD group were (553±83) and (239±65) mL respectively, which were significantly higher than (440±77) and (175±49) mL of exudate of patients in silver sulfadiazine group (t=3.44, 2.24, P<0.05). On treatment day 7, the volume of drainage fluid of patients in VSD group was (21±8) mL, which was significantly lower than (149±44) mL of exudate of patients in silver sulfadiazine group (t=-12.61, P<0.01). (2) After 7, 14, and 21 days of treatment, the wound healing rates of patients in VSD group were (39±6) %, (74±10) %, and (92±3) %, respectively, which were significantly higher than (25±3) %, (59±6) %, and (77±6) % in silver sulfadiazine group (t=7.07, 5.59, 7.09, P<0.01). (3) Before treatment, the serum levels of TNF-α and IL-8 of patients in the two groups were similar. After 7 days of treatment, the serum levels of TNF-α and IL-8 of patients in VSD group were significantly lower than those in silver sulfadiazine group (t=-8.75, -8.04, P<0.01). (4) The pain score during dressing change and medical cost of patients in VSD group were significantly lower than those in silver sulfadiazine group (t=-4.28, -7.56, P<0.01), while the discharge satisfaction score of patients in VSD group was significantly higher than that in silver sulfadiazine group (t=10.91, P<0.05). Conclusions: The application of VSD technology in clinical alkali burn wounds can effectively promote the removal of residual lye, alleviate the further damage of lye to skin tissue, shorten the wound healing time, effectively remove inflammatory mediators, reduce the pain of dressing change, decrease the total cost of treatment, and enhance satisfaction of patient.

Identification of genes associated with castration‑resistant prostate cancer by gene expression profile analysis

Prostate cancer (CaP) is a serious and common genital tumor. Generally, men with metastatic CaP can easily develop castration‑resistant prostate cancer (CRPC). However, the pathogenesis and tumorigenic pathways of CRPC remain to be elucidated. The present study performed a comprehensive analysis on the gene expression profile of CRPC in order to determine the pathogenesis and tumorigenic of CRPC. The GSE33316 microarray, which consisted of 5 non‑castrated samples and 5 castrated samples, was downloaded from the gene expression omnibus database. Subsequently, 201 upregulated and 161 downregulated differentially expressed genes (DEGs) were identified using the limma package in R and those genes were classified and annotated by plugin Mcode of Cytoscape. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed using Database for Annotation, Visualization and Integrated Discovery and KEGG Orthology Based Annotation System 2.0 online tools to investigate the function of different gene modules. The BiNGO tool was used to visualize the level of enriched GO terms. Protein‑protein interaction network was constructed using STRING and analyzed with Cytoscape. In conclusion, the present study determined that aldo‑keto reductase 3, cyclin B2, regulator of G protein signaling 2, nuclear factor of activated T‑cells and protein kinase C a may have important roles in the development of CRPC.

Changes of snoring sound after relocation pharyngoplasty for obstructive sleep apnoea: the surgery reduces mean intensity in snoring which correlates well with apnoea-hypopnoea index

OBJECTIVE

To investigate objective changes of snoring after surgery in patients with obstructive sleep apnoea (OSA) and correlate these with changes in the apnoea-hypopnoea index (AHI).

DESIGN

Prospective case series.

SETTING

A novel measurement, Snore Map, was used to analyse full-night snore sounds in terms of the maximal/mean intensity, peak/mean frequency, snoring index and energy type (Snore Map type, 0-4). Snore sound was classified into three bands according to frequency energy spectrum: B1 (40-300 Hz), B2 (301-850 Hz) and B3 (851-2000 Hz).

PARTICIPANTS

Thirty-four male and two female OSA patients (mean age, 39 years; mean AHI, 53.1/h; mean body mass index, 26.8 kg/m(2) ) with favourable anatomic structure were consecutively enrolled.

MAIN OUTCOME MEASURES

Parameters of polysomnographies and Snore Maps at baseline and six months after operation were compared. Statistical significance was set at P < 0.05.

RESULTS

Thirty-two patients completed this study. The mean reduction in the total-snoring index was insignificant but there were significant decreases in total mean intensity, total peak frequency, total mean frequency and Snore Map type after surgery. There were also significant decreases in the mean intensity in all three bands, the snoring index in B2/B3 and the mean frequency in B1 postoperatively. Changes in the total mean intensity, total mean frequency, B2 mean intensity and B3 snoring index positively correlated with change in the AHI.

CONCLUSIONS

Relocation pharyngoplasty significantly decreases both the snoring sound intensity and snoring frequency. These reductions are directly proportional to the improvement of OSA.

[Effect of nerve growth factor on the visual evoked potential of rats pretreated by CS2]

AIM

To study the therapeutic effect of NGF to rats with newly CS2 deranged.

METHODS

The model of rats with deranged visual nerve was made by CS2 (i.p) for three weeks. Rats were then treated with different dosages of NGF for three weeks, and the changes of visual evoked potential were determined.

RESULTS

The latency of PREP and FEP shortened significantly vs control after treatment for 10 and 20 days.

CONCLUSION

NGF can improve the conductivity of visual with dose-effect relationship, suggesting that NGF has a significant therapeutic effect on the deranged visual nerve.

Pharmacokinetics, tissue distribution and photodynamic therapy efficacy of liposomal-delivered hypocrellin A, a potential photosensitizer for tumor therapy

Hypocrellin A, from Hypocrella bambusae, is a novel photosensitizer of high singlet oxygen quantum yield for photodynamic therapy (PDT). Tissue distributions were studied in tumor-bearing mice as a function of time following administration. The tumor model was S-180 sarcoma transplanted into one hind leg of male Kunming mice; hypocrellin A (HA) was delivered to the mice by intravenous injection of 5 mg/kg of body weight as a suspension either as a unilamellar liposome or in dimethyl sulfoxide (DMSO)-solubilized saline. The HA was isolated from several tissues and organs, as well as tumors and peritumoral muscles and skin. Quantitation was performed by a high-performance liquid chromatographic technique with detection that utilizes the native fluorescence of HA. Independent of the delivery system, the dye was retained in tumors at higher concentrations than in normal tissues, except for kidney, liver, lung and spleen. The dye retention in tumors was high and was vehicle dependent. For the liposomal system, the maximal accumulation in tumor and maximal ratios of dye in tumor versus peritumoral muscle and skin occurred 12 h postinjection; for the DMSO saline system, the maximal ratio occurred earlier, 6 h postadministration. Liposomal delivery improved the selective accumulation of the dye in tumor with higher maximal levels in tumor and higher ratios of tumor-to-muscle and tumor-to-skin. Levels of dye were very low or not detectable in the brain. The PDT efficacy of HA in the liposome and DMSO saline systems was determined by evaluating the tumor volume regression percent. The PDT efficacy of HA in liposomes was highest when light treatment was performed at 12 h postinjection, consistent with the highest retention of HA in tumors. Similarly, the maximal PDT efficacy in DMSO saline was attained at 6 h postinjection, the highest HA retention point in tumor. Moreover, the peak PDT efficacy of HA in liposomes was much higher than that of HA in DMSO saline and even hematoporphyrin monomethylether.

[Stimulatory effect of vasoactive intestinal peptide microinjected into dorsal vagal complex on gastric acid secretion in rats]

Effects of microinjection of vasoactive intestinal peptide (VIP) into cisterna magna, dorsal vagal complex (dorsal motor nucleus of the vagus, nucleus tractus solitarius and area postrema) and spinal subarachnoid space on gastric acid secretion (GAS) were observed in Ghosh-Schild's rats. The results were as follows: (1) VIP (10 micrograms) injected into the cisterna magna significantly stimulated GAS reaching a peak at 60-100 min after injection and lasting for more than 2.5 h. (2) The increase could be completely abolished by bilateral subdiaphragmatic vagotomy. (3) 20-30 min after injection of 1 microgram VIP into the dorsal vagal complex could also induce a peak increase in GAS. (4) Intrathecal injection of VIP (10 micrograms) did not affect GAS. The results indicate that central VIP-stimulated GAS is mediated by vagus from a special region of dorsal vagal complex.

[Effects of berberine on synthesis of platelet TXA2 and plasma PGI2 in rabbits]

Using radioimmunoassay, we found that berberine (0.50 mol.L-1) inhibited dose-dependently collagen-, ADP-, and arachidonic acid (AA)-induced TXA2 release from platelets. Berberine (25 mg.kg-1) iv lowered rabbit plasma level of PGI2 from 0.92 +/- 0.20 to 0.61 +/- 0.08 ng.ml-1 after 60 min. The results suggest that berberine inhibits AA release from cell membrane phospholipids and its metabolism.

Studies on New Components and Stereochemistry of Diterpenoids from Trypterygium wilfordii

An extensive investigation of the petroleum ether extract of TRIPTERYGIUM WILFORDII plants have revealed the presence of four new compounds, triptonoterpene, neotriptonoterpene, triptonodiol, and neotriptonolide, in addition to the diterpenes isolated and characterized earlier. The structures of these novel natural products have been elucidated.

Guinea pig pancreatic polypeptide: structure and pancreatic content

Guinea pig (GP) pancreatic polypeptide (PP) has been purified from an acid-alcohol extract of 6 GP pancreata by a series of 3 HPLC steps. The sequence for GP PP as compared with that of beef and human is shown: (Sequence: see text). In a single GP pancreas weighing 2.4 g the total PP content was 1.0 nmol and the total glucagon content 61 nmol; in a single dog pancreas weighing 35 g the total PP was 385 nmol and the total glucagon 81 nmol. The relatively low content of PP in GP pancreas is consistent with the fact that the GP lacks a ventral pancreas, the region in which PP is found in highest concentration. The high glucagon content of GP pancreas is consistent with that reported in earlier studies.

Guinea pig glucagon differs from other mammalian glucagons

Mammalian glucagon is thought to be highly conserved. Glucagons from pig, cow, human, rat, and hamster have identical amino acid sequences, whereas the amino acid contents of rabbit and camel glucagons are consistent with this 29-amino acid sequence. It had earlier been reported that guinea pig (GP) glucagon contains 40 amino acids. In the current study, glucagon was purified from two GP pancreata by a series of three HPLC steps after acid-alcohol extraction and acetone precipitation. GP glucagon is a 29-amino acid peptide that differs from other mammalian glucagons by substitution of Gln for Asp in position 21, Leu for Val in position 23, Lys for Gln in position 24, Leu for Met in position 27, and Val for Thr in position 29. In view of the marked changes in the COOH-terminal of GP glucagon, receptor binding studies were performed using both rat and GP liver membranes. Labeled synthetic porcine glucagon has similar binding in the two systems and its binding is inhibited to a similar degree by synthetic porcine glucagon, whereas GP glucagon is 10-fold less potent at inhibiting binding in both systems. This suggests that glucagon receptor binding sites in the GP are evolutionarily more conserved than is GP glucagon.

Ontogeny of immunoreactive cholecystokinin, vasoactive intestinal peptide, and secretin in guinea pig brain and gut

The ontogeny of cholecystokinin (CCK), vasoactive intestinal peptide (VIP), and secretin (SEC) as well as other brain and gut peptides has been extensively studied in the rat. However, since the guinea pig (GP) appears to be functionally more mature at birth than the rat, we hypothesized that the concentrations of brain peptides, but not necessarily of gut peptides, in GP neonates would be closer to adult concentrations than those in the rat. The concentration and organ content of these three peptides were determined at birth, at 7, 14, 21, and 28 days of age, and in the adult in various portions of the gastrointestinal tract and brain. VIP and CCK in the brain at birth are 75% of adult levels compared to less than 10% in the rat. VIP concentrations in the stomach, duodenum, and jejunum are relatively constant from birth through adult life, whereas in the rat, the intestinal VIP concentration increased 3- to 4-fold from birth to adulthood. SEC, which in the gut is found only in mucosal tissues, peaked at birth, remained low from 7-28 days of age, and rose again in the adult. CCK, which in the gut is found in both the mucosa and muscle wall, like SEC peaks at birth, then remains low from 7-28 days of age, and rises in the adult. It is concluded that the GP neuronal tissues are much more mature at birth than are those in the rat.

[Cytochemical demonstration of 3 beta-hydroxysteroid dehydrogenase activity in human corpora lutea (author's transl)]

3 beta-hydroxysteroid dehydrogenase (3 beta-HDS) activity was demonstrated ultrastructurally in human corpora lutea obtained from the women aged 32-46 who were treated by the hysterectomy for various gynecological indications. The corpora lutea were removed from ovaries and cut into small pieces of 1 mm3. Specimens were incubated at 25 degrees C for 20 min. in the media containing dehydroepiandrosterone 0.6 mg, 0.1 M sodium citrate 0.3 ml, 5 mM potassium ferricyanide 1 ml, 30 mM copper sulfate 1 ml, N.A.D. 3.6 mg, sucrose 1.0 g and 0.1 M phosphate buffer (pH 7.2) 6 ml. For a control study, 1.5 mg cyanoketone (by the courtesy of Dr G.O. Pott), the specific inhibitor for 3 beta-HSD, was added to the media. The materials were fixed in 4% glutaraldhyde and 1% OsO4 and embedded in Epon 812. Electron dense reaction products of copper ferrocyanide were observed in smooth endoplasmic reticulum (sER) and in intercristal and outer space of mitochondria. In control studies, 3 beta-HSD activity were completely abolished. It is concluded that not only sER but also mitochondria has 3 beta-HSD activity in human corpora lutea. Furthermore, mitochondria seems to have capability to synthetize progesterone from cholesterol by itself.