[Pulmonary rehabilitation guidelines in the principle of 4S for patients infected with 2019 novel coronavirus (2019-nCoV)]

A recent epidemic of pneumonia cases in Wuhan China was caused by a novel coronavirus with strong infectivity, the 2019 novel coronavirus (2019-nCoV). The article provides the pulmonary rehabilitation (PR) methods in the principle of 4S (simple, safe, satisfy, save) for patients with pneumonia caused by the novel coronavirus, shows how to establish a ventilative and convectional PR environment to prevent the spread of virus through droplets, how to guide the patients to carry out PR, how to carry out respiratory muscle training, effective cough, expectoration, sneeze, general exercise, digestive function rehabilitation and psychological rehabilitation, and how to clean and disinfect the PR environment.

The effect of acetylation on the protein stability of BmApoLp-III in the silkworm, Bombyx mori

Acetylation is an important, reversible posttranslational modification to a protein. In a previous study, we found that there were a large number of acetylated sites in various nutrient storage proteins of the silkworm haemolymph. In this study, we confirmed that acetylation can affect the stability of nutrient storage protein Bombyx mori apolipophorin-III (BmApoLp-III). First, the expression of BmApoLp-III could be upregulated when BmN cells were treated with the deacetylase inhibitor panobinostat (LBH589); similarly, the expression was downregulated when the cells were treated with the acetylase inhibitor C646. Furthermore, the increase in acetylation by LBH589 could inhibit the degradation and improve the accumulation of BmApoLp-III in BmN cells treated with cycloheximide and MG132 respectively. Moreover, we found that an increase in acetylation could decrease the ubiquitination of BmApoLp-III and vice versa; therefore, we predicted that acetylation could improve the stability of BmApoLp-III by competing for ubiquitination and inhibiting the protein degradation pathway mediated by ubiquitin. Additionally, BmApoLp-III had an antiapoptosis function that increased after LBH589 treatment, which might have been due to the improved protein stability after acetylation. These results have laid the foundation for further study on the mechanism of acetylation in regulating the storage and utilization of silkworm nutrition.

A robust model for estimating thermal conductivity of liquid alkyl halides

Thermal conductivity is an essential thermodynamic property in chemical engineering application. As a result, estimating the thermal conductivity of organic compounds is of significance in industry production. Alkyl halides are important organic intermediates and raw materials, but little investigations have been performed to estimate their thermal conductivity. In this study, the structures of compounds were optimized in Gaussian 09W and molecular descriptors were extracted by Dragon software. Finally, we developed a 6-descriptor linear quantitative structure-property relationship (QSPR) model to estimate the thermal conductivity of alkyl halides using the genetic function approximation (GFA) method. Validation proved that the developed model had goodness-of-fit, robustness and predictive ability. The r²_pred and root-mean-square error (RMSE_P) of prediction set for the model were equal to 0.9745 and 0.0035, respectively. Meanwhile, the applicability domain was visualized by means of the Williams plot. This study provides a new model for estimating the thermal conductivity of this important class of chemicals.

Impact of contouring variability on oncological PET radiomics features in the lung

Radiomics features extracted from oncological PET images are currently under intense scrutiny within the context of risk stratification for a variety of cancers. However, the lack of robustness assessment poses problems for their application across institutions and for broader patient populations. The objective of the current study was to examine the extent to which radiomics parameters from oncological PET vary in response to manual contouring variability in lung cancer. Imaging data employed in the study consisted of 26 PET scans with lesions in the lung being created through the use of an anthropomorphic phantom in conjunction with Monte Carlo simulations. From each of the simulated lesions, 25 radiomics features related to the gray-level co-occurrence matrices (GLCOM), gray-level size zone matrices (GLSZM), and gray-level neighborhood difference matrices (GLNDM) were extracted from ground truth contour and from manual contours provided by 10 raters in regard to four intensity discretization schemes with number of gray levels of 32, 64, 128, and 256, respectively. The impact of interrater variability in tumor delineation upon the agreement between raters on radiomics features was examined via interclass correlation and leave-p-out assessment. Only weak and moderate correlations were found between segmentation accuracy as measured by the Dice coefficient and percent feature error from ground truth for the vast majority of the features being examined. GLNDM-based texture parameters emerged as the top performing category of radiomcs features in terms of robustness against contouring variability for discretization schemes engaging number of gray levels of 32, 64, and 128 while GLCOM-based parameters stood out for discretization scheme engaging 256 gray levels. How and to what extent interrater reliability of radiomics features vary in response to the number of raters were largely feature-dependent. It was concluded that impact of contouring variability on PET-based radiomics features is present to varying degrees and could be experienced as a barrier to convey PET-based radiomics research to clinical relevance.

Fe/Fe3C encapsulated in nitrogen source-mediated active-N-rich defective carbon nanotubes for bifunctional oxygen catalysis

Fe-N-OCNT as a bifunctional catalyst displays an excellent performance and its possible chemical components contribute to its activity.

Combined Effect of Osteoporosis and Poor Dynamic Balance on the Incidence of Sarcopenia in Elderly Chinese Community Suburban-Dwelling Individuals

OBJECTIVES

Given the increasing prevalence of osteoporosis and the important role dynamic balanced plays in the assessment of muscle function, we aimed to examine the joint and separate effects of osteoporosis and poor dynamic balance on the incidence of sarcopenia in Chinese elderly individuals.

DESIGN

This study was conducted on 658 (44.4% male) Chinese suburban-dwelling participants with a mean age of 68.42 ± 5.43 years who initially had no sarcopenia and were aged ≥60 years. A quantitative ultrasound scan of each participant's calcaneus with a T score less than -2.5 was used to identify the prevalence of osteoporosis. Sarcopenia was diagnosed according to the Asian Working Group for Sarcopenia criteria. We assessed dynamic balance using the Timed Up and Go Test (TUGT). Participants who scored in the top 20% on the TUGT were defined as having poor dynamic balance.

RESULTS

After a follow-up of three years, the incidence of sarcopenia in the general population was 8.1% (9.6% in males, 6.8% in females). The incidence of sarcopenia was progressively greater in people suffering from both osteoporosis and poor dynamic balance (OR=2.416, 95%CI=1.124-5.195) compared to those who only had osteoporosis (OR=0.797, 95%CI=0.378-1.682) or poor dynamic balance (OR=1.226, 95%CI=0.447-3.363) in models without adjustments. Even after adjusting for potential confounders, the result still held true (OR=2.431, 95%CI=1.053-5.614).

CONCLUSIONS

In our study, we found individuals who suffered from both osteoporosis and poor dynamic balance simultaneously had a significantly higher incidence of sarcopenia than those who suffered from either one or the other.

Characterization of Fecal Shiga Toxin-Producing Escherichia coli from Post-Weaning Cattle

ObjectivesShiga toxin-producing E. coli (STEC), which are often found in the intestinal tract of cattle and in their fecal matter, are among the most common foodborne pathogens of concern in beef production. Contamination from the fecal matter, both directly and indirectly, during harvest may compromise the safety of the beef products, which can have devastating impact on consumers and producers alike. While the microbial load present in cattle fecal matter may change as the cow matures, previous research has generally focused on analysis of the pathogen load late in the life cycle of cattle. There is merit in the analysis of this load earlier in the life cycle of cattle, as this may serve to subsequently control the pathogen load during later stages of production. As such, this study aims to assess the prevalence and characteristics of STEC in beef cattle production at the early post-weaning stage.Materials and MethodsRectal fecal samples from post-weaning cattle (n = 68) were collected. Ten grams of each sample was mixed and manually homogenized with 90mL tryptic soy broth (TSB) with added phosphates. The homogenized samples were spread-plated on CHROMagar STEC plates and incubated at 35°C for 24h before enumeration. To determine STEC prevalence, the homogenized samples were incubated at 42°C for 6 h, and streaked onto a second set of CHROMagar STEC plates, which were incubated at 35°C for 24h. Colonies with a purple coloration were STEC-positive. Two random STEC-presumptive colonies from each sample were tested via subsequent PCR amplification and gel electrophoresis to confirm the presence of stx1, stx2, and/or eae genes.Acid-resistant strains of presumptive STEC colonies from the enriched samples were collected and inoculated into TSB for recovery. One hundred microliters of the inoculated sample were then transferred into TSB without dextrose and incubated at 35°C for 24h, and finally challenged in acidified TSB without dextrose (pH = 3.50) for 1h and 6h. One hundred microliters of each survival sample were plated onto tryptic soy agar (TSA), and incubated at 35°C for 48h.ResultsThe fecal samples had an average 4.79 ± 1.24 log CFU/g (ranging 2.30 to 6.83) of STEC colonies. All samples were STEC-positive, as all samples had at least one of the three genes tested for (stx1, stx2, eae). All sixty-eight samples were confirmed positive for gene stx1, 12% (8 of 68) samples were confirmed positive for stx2, 62% (42 of 68) of samples were confirmed positive for eae, and 12% (8 of 68) were positive for all three genes. Of 67 samples tested for acid resistance, 34% (23 of 67) survived after 6 h in acidified growth media (pH = 3.50).ConclusionThis study provided preliminary data on the pathogen load of early post-weaning cattle. The prevalence of acid resistance shown may be a possible cause of concern, as these surviving bacteria can survive high acidic conditions. This may expedite the spread of acid-resistant pathogens within the food supply chain as acidic antimicrobial chemicals become ineffective in reducing pathogen populations. These results may be used as a baseline for future research regarding STEC prevalence or acid resistance aimed at reducing pathogen load in beef cattle production. Given the prevalence of acid resistance, further development is recommended for non-acid post-harvest antimicrobial interventions to reduce the presence of acid resistant STEC.

Adaptive Event-Triggered Transmission Scheme and H∞ Filtering Co-Design Over a Filtering Network With Switching Topology

This paper addresses the distributed adaptive event-triggered H_∞ filtering problem for a class of sector-bounded nonlinear system over a filtering network with time-varying and switching topology. Both topology switching and adaptive event-triggered mechanisms (AETMs) between filters are simultaneously considered in the filtering network design. The communication topology evolves over time, which is assumed to be subject to a nonhomogeneous Markov chain. In consideration of the limited network bandwidth, AETMs have been used in the information transmission from the sensor to the filter as well as the information exchange among filters. The proposed AETM is characterized by introducing the dynamic threshold parameter, which provides benefits in data scheduling. Moreover, the gain of the correction term in the adaptive rule varies directly with the estimation error and inversely with the transmission error. The switching filtering network is modeled by a Markov jump nonlinear system. The stochastic Markov stability theory and linear matrix inequality techniques are exploited to establish the existence of the filtering network and further derive the filter parameters. A co-design algorithm for determining H_∞ filters and the event parameters is developed. Finally, some simulation results on a continuous stirred tank reactor and a numerical example are presented to show the applicability of the obtained results.

GAS5 promotes podocyte injury in sepsis by inhibiting PTEN expression

OBJECTIVE

To investigate the potential role of long noncoding RNA (lncRNA) growth arrest specific transcript 5 (GAS5) in sepsis-induced podocyte injury and its underlying mechanism.

MATERIALS AND METHODS

The sepsis model was established by lipopolysaccharide (LPS) induction in podocytes. The expression levels of Nephrin and GAS5 were detected by quantitative Real-time polymerase chain reaction (qRT-PCR) after LPS induction in podocytes for 12 h, 24 h and 36 h, respectively. Western blot was used to detect the expression level of Nephrin in sepsis-induced podocytes. The mRNA expressions of GAS5 and Nephrin in podocytes were detected after transfection of GAS5 siRNA. Albumin influx in podocytes after GAS5 knockdown was detected by Transwell assay. Western blot was used to detect the protein expression of Snail in sepsis after GAS5 knockdown. The target gene of GAS5 was predicted by bioinformatics analysis. QRT-PCR and Western blot were used to detect the protein and mRNA levels of PTEN (phosphatase and tensin homolog deleted on chromosome ten). Nephrin expression and the albumin inflow after PTEN knockdown were then measured. The expression of PI3K/AKT/GSK3β was also detected after GAS5 was downregulated while PTEN was upregulated.

RESULTS

LPS stimulation downregulated the mRNA expression of Nephrin in podocytes and achieved the lowest level at 24 h. The protein expression change of Nephrin was consistent with its mRNA expression. In the septic state, the albumin influx of podocytes remarkably increased, but the function of podocyte barrier was weakened. Besides, GAS5 expression decreased in a time-dependent manner in LPS-induced podocytes. After GAS5 knockdown by siRNA, Nephrin expression and the function of podocyte barrier were significantly reduced. Snail expression was also upregulated in septic state, and GAS5 knockdown increased the expressions of phosphorylated Snail and PI3K/AKT/GSK3β. After knockdown of GAS5, the mRNA and protein levels of PTEN significantly decreased, which was contract to the expression of Snail. However, overexpression of PTEN could reverse the promotive effect of GAS5 on PI3K/AKT activation.

CONCLUSIONS

GAS5 expression decreased in sepsis-induced podocyte injury, and GAS5 was involved in regulating sepsis-induced podocyte injury by reducing PTEN expression.

[Clinical application of lobulated transplantation of free anterolateral thigh perforator flap in the treatment of electric burns of limbs]

Objective: To explore the clinical efficacy of lobulated transplantation of free anterolateral thigh perforator flap in repairing electric burn wounds of limbs. Methods: From August 2014 to April 2019, 19 patients with electric burns in the limbs were hospitalized in our unit, including 18 males and 1 female, aged 20-58 years. There were 37 wounds deep to bone. The area of wounds ranged from 3.0 cm×2.0 cm to 40.0 cm×8.0 cm. Multiple-perforator-based anterolateral thigh flap was designed and resected. Then the flap was lobulated taking the respective perforators of the lateral circumflex femoral artery as the axial vessels before being transplanted to the debrided wounds in the limbs. The blood vessel trunk or the perforator vessels of flap lobes were anastomosed with the respective vessels in the recipient sites. The wounds were repaired with respective lobes of the flap when repairing multiple wounds in one surgical procedure, whereas the lobes were spliced or staggered to cover the wound to fit the shape of wound when repairing a single irregular wound in one surgical procedure. For the limb with distal blood supply disorder, the blood supply branch of flap was used to reconstruct the blood supply. If necessary, an appropriate length of vein was taken for transplantation. The improvement of reconstructed blood supply was observed. The number of surgeries, the number of anterolateral thigh perforator flaps, the number and size of flap lobes, the number of anastomosed vessels in each surgery, the treatment of the donor sites, the length of each surgery, the postoperative complications and survival condition of flap lobes were recorded. The upper extremity function was evaluated with the Carroll's Upper Extremity Function Test Scale, and the patients' satisfaction degree with the therapeutic effect of each surgery was investigated with a 5-point Likert Scale during follow-up. Surgeries were divided into single wound group of repairing one wound at one time and multiple wounds group of repairing two or more wounds at one time. The number of anastomosed vessels in each surgery, the treatment of the donor sites, the length of each surgery, and the postoperative survival condition of the flap lobes were compared between the two groups. Surgeries were divided into early group of performing surgery within post burn day 7 and late group of performing surgery on post burn day 7 and beyond. The postoperative complications and survival condition of flap lobes, the evaluation score of upper limb function and the patients' satisfaction degree with the therapeutic effect of each surgery at the last follow-up were compared between the two groups. Data were processed with independent sample t test, Mann-Whitney U test, or Fisher's exact probability test. Results: The blood supply of 5 patients with distal hand or finger blood supply disorder recovered or improved significantly after vascular transplantation. A total of 46 lobes [(2.2±0.4) lobes per flap] were obtained from 21 anterolateral thigh perforator flaps in 19 patients with 21 surgeries. The area of flap lobes ranged from 4.0 cm×3.0 cm to 24.0 cm×13.0 cm. In each surgery, 2.0 (1.5, 3.0) arteries and 3.0 (2.0, 3.0) veins were anastomosed. Six donor sites were repaired by thin split-thickness scalp, and 15 donor sites were closed directly. The duration of each surgery was (8.9±1.7) h. After surgery, bleeding and hematoma occurred in 2 flap lobes and local infection occurred in 5 flap lobes, which were improved after management. Vascular crisis occurred in 4 flap lobes, and exploratory surgeries were performed, after which 2 lobes survived, while the other 2 lobes necrotized and were repaired by other methods. The rest flap lobes survived well. After each postoperative follow-up of 3 to 60 months, the flap covering areas of the limbs were well-recovered. At the last follow-up, the function evaluation score of 20 affected upper limbs was 85 (63, 90) points, and the score of patients' satisfaction degree with the therapeutic effect of each surgery was (4.4±0.7) points. A total of 30 flap lobes were obtained in 14 surgeries and repaired 30 wounds respectively in multiple wounds group, and 16 flap lobes were obtained in 7 surgeries and were spliced to repair 7 large irregular wounds in single wound group. There were no statistically significant differences in the number of anastomosed artery or vein in each surgery, and the duration of each surgery between multiple wounds group and single wound group (Z=0.240, 0.081, t=0.180, P>0.05), and the condition of skin grafting in the donor sites and the postoperative survival of the flap lobes in multiple wounds group were similar to those in single wound group (P>0.05). A total of 22 flap lobes were obtained in 10 surgeries and repaired 18 wounds in early group, and 24 flap lobes were obtained in 11 surgeries and repaired 19 wounds in late group. The incidence of postoperative hematoma, infection, vascular crisis, and survival of flap lobes in early group were similar to those in late group (P>0.05). There were no statistically significant differences in the patients' satisfaction degree with the therapeutic effect of each surgery at the last follow-up between early group and late group (t=0.701, P>0.05). At the last follow-up, the function evaluation score of 9 upper limbs in early group was 90 (85, 97) points, significantly higher than 80 (40, 85) points of 11 upper limbs in late group (Z=2.431, P<0.05). Conclusions: Free lobulated anterolateral thigh perforator flap is suitable for simultaneous repair of multiple electric burn wounds of limbs, as well as the repair of a single large irregular wound. It has the clinical advantages of less damage to the donor site and good repair quality. The early flap transplantation is beneficial to improve the function of limbs with electric burns.

[Progress of immune checkpoint inhibitors in neoadjuvant therapy of non-small cell lung cancer]

Lung cancer carries the highest morbidity and mortality out of all malignancies in the world. About 85% of all cases are non-small cell lung cancer (NSCLC). Surgery is currently the optimal treatment for early-stage NSCLC, however, the postoperative recurrence rate is relatively high and the long-term survival of these patients is still a problem to be overcomed. Previous studies have shown that early-stage NSCLC patients may benefit from preoperative neoadjuvant chemotherapy when compared to surgery alone, although the benefit is only moderate. More recent publications indicate that immune checkpoint blockade may have better potential in neoadjuvant therapy, with reported major pathological response rates at 20% to 85%, compared to chemotherapy alone. Phase Ⅲ random clinical trials are being implemented to confirm the effect of neoadjuvant immunotherapy in NSCLC. Meanwhile, a number of questions remain unanswered, including the time and course of neoadjuvant immunotherapy, the evaluation criteria of immune-related efficacy, the standardization of pathological evaluation, and how to avoid delays in surgery or misjudgment caused by pseudo-progression.

Wheat-associated microbiota and their correlation with stripe rust reaction

AIMS

This study was aimed at revealing the composition of microbiota in leaves, roots and rhizosphere soil of wheat plants that are resistant or susceptible to stripe rust, one of the most widely destructive leaf diseases in wheat production.

METHODS AND RESULTS

A total of 36 wheat plants that showed resistant or susceptible reactions to stripe rust were sampled. Three compartments of each plant including leaves, roots and rhizosphere soil were used for whole-genomic DNA extraction and the DNA samples were subjected to high-throughput 16S rRNA gene sequencing. A total of 2885 operational taxonomic units (OTUs) were revealed from the sequencing, and they mainly distributed in the phylum of Proteobacteria. Twenty-nine OTUs formed the core microbiota of wheat plants. The differences between above- and below-ground environments could explain most of the dissimilarity of wheat-associated microbial communities. Therefore, those microbes that were able to adapt to the above-ground (leaf) environment might be more important resources for biocontrol agents against stripe rust, and they could be from genera Hymenobacter, Flavobacterium, Chitinophage, Flavisolibacter, Niastella, Mucilaginibacter, Pedobacter, Aquincola, Massilia, Citrobacter, Cronobacter, Ewingella, Acinetobacter and Pseudomonas. No matter the microbial taxa were significantly selected by the resistant or susceptible wheat plants, they contained the members with plant growth promoting (PGP) features and could be used as potential biocontrol agents to reduce stripe rust damage.

CONCLUSIONS

The core microbiota associated with wheat plants and microbial taxa that were significantly correlated with reactions to stripe rust were identified in this study.

SIGNIFICANCE AND IMPACT OF THE STUDY

Few studies had been done on the microbiota associated with wheat so far. Our study will not only provide fundamental knowledge about the composition of wheat-associated microbiota but also reveal the microbial taxa that have the potential to be integrated into the strategy of stripe rust management.

[Significance of prostate central gland/total gland volume ratio combined with PSA in the diagnosis of prostate cancer patients]

Objective: To explore the significance of prostate central gland/total gland volume (PVc/PV) ratio combined with PSA in the diagnosis of PSA 4-20 ng/ml prostate cancer patients. Methods: Data of patients undergoing prostate puncture in Minghang Branch, Zhongshan Hospital from July 2015 to December 2018 were retrospectively analyzed. The anteroposterior, transverse and axial diameters of the prostate and the central prostate gland were measured by magnetic resonance imaging (MRI). The differences of tPSA, f/tPSA, PSAD and PVc/PV between the prostate cancer group and non-prostate cancer group were compared. Receiver operating characteristic (ROC) curves of prostate cancer diagnosis were plotted according to tPSA, f/tPSA, PSAD, PVc/PV alone and PVc/PV combined with tPSA, respectively, and the area under the curve (AUC) was calculated and compared using tPSA as the reference. Results: There was no significant difference in tPSA between the two groups (P>0.05). However, significant differences were observed in f/tPSA, PSAD and PVc/PV between the two groups (P<0.05). The AUC value of PVc/PV combined with tPSA, PVc/PV and PSAD was 0.901 2,0.866 7 and 0.848 1,respectively, which were statistically different from that of tPSA (P<0.05). The AUC value of f/tPSA was 0.716, which was not statistically different from that of tPSA (P>0.05). Conclusion: The PVc/PV ratio combined with tPSA can be used as an important reference index for the diagnosis of prostate cancer in PSA 4-20 ng/ml patients.

P1822Pocket-size mobile echocardiographic device screening for thoracic aortic aneurysm in asymptomatic hypertensive patients

Background

Patients with hypertension may develop thoracic aortic aneurysm (TAA) that can be asymptomatic but potentially life-threatening. We sought to assess the prevalence of asymptomatic TAA among hypertensive patients and define the effectiveness of a TAA point-of-care screening program using pocket-size mobile echocardiographic (PME) devices.

Methods

We prospectively performed transthoracic echocardiography for TAA screening using a PME device on 1529 hypertensive patients (age, 62y [30y to 85y], 824 men) who attended our hypertension specialist clinic between June 2016 and July 2018. Measurement of the dimensions of the aortic sinus, sinotubular junction, ascending aorta, aortic arch, and descending thoracic aorta were obtained through multiple standard echo views.

Results

The prevalence of TAA (defined as maximum aortic diameter of ≥4.5cm and/or >50% diameter of the adjacent aorta) in our study population was 7.3% (111/1529), with distal ascending aorta as the most frequent location (Figure). Multiple logistic regression analysis identified male gender, older age, and presence of heart valve disease as independent factors associated with TAA (all p<0.05).

Figure 1

Conclusions

Asymptomatic TAA is common among asymptomatic hypertensive patients. Point-of-care use of PME device is effective in detecting TAA in a clinic setting. Such approach may be useful for early detection of TAA among at-risk patients allowing aggressive blood pressure control and early surgical intervention to prevent catastrophic complications such as aortic dissection or rupture.

Acknowledgement/Funding

Health and Medical Research Fund of the Hong Kong Government

A new method for detecting thermal characteristics of slow-wave structure of helix traveling-wave tube using external heat source

This paper presents a method for detecting the heat-dissipation capability of the slow-wave structure (SWS) in a helix traveling wave tube (TWT) using an external heat source. This method utilizes transient temperature rise detection technology and structure function method to nondestructively detect the heat-dissipation capability of SWS. An analytical model is built, and the method is verified by using the simulation tool ANSYS. Furthermore, a dedicated test probe is designed based on this method, and a 2.5-mm diameter helix TWT is measured. The results reveal that the method can effectively detect parts with large thermal resistance in SWS, thereby providing the basis for eliminating the failure products and improving the production process of SWS.

Reconstruction of Vehicle-pedestrian Collision Road Traffic Accidents Based on PC-Crash Software

Abstract

Objective To discuss the application value of vehicle-pedestrian collision road traffic accidents reconstruction based on PC-Crash software in forensic identification. Methods A case of vehicle-pedestrian collision was chosen based on a tachograph, then PC-Crash software was applied to construct a vehicle-pedestrian collision model, and reconstruct the vehicle-pedestrian collision road traffic accident. Finally, the process of vehicle-pedestrian collision was reproduced. Results In accident reconstruction, when the car speed was lower than 50km/h, the landing point of the pedestrian after collision was in the front of the car. When the car speed was higher than 50 km/h, after collision, the pedestrian flipped towards the car roof and landed behind the car. With the increase of vehicle speed, throwing distance of the pedestrian increased continuously. When the vehicle collision speed reached 60 km/h, the experimental results in this case were basically consistent with the actual situation of the case. Head acceleration of the pedestrian was at the maximum （1 655.70 m/s²） at 0.080 s. Chest acceleration of the pedestrian increased from 597.63 m/s² to the peak 675.52 m/s² at 0.055-0.060 s. Tibia acceleration of the pedestrian increased from 759.26 m/s² to the first peak 1 367.06 m/s², then reached the maximum speed （1 718.19 m/s²） at 1.225 s. Conclusion The process of vehicle-pedestrian collision road traffic accidents can be reconstructed based on PC-Crash software under a situation of limited conditions, and can further clarify the speed of the vehicle, the location and degree of human body injury as well as the mechanism of damage of the pedestrian in the accident. Therefore, PC-Crash software has a certain practical value in forensic identification of road traffic accidents.

Long-Range Mass Transport during Structural Transitions in Metallic Glass-Forming Melts

We investigate the structure and dynamics of the bulk metallic glass-forming alloys Zr_{41.2}Ti_{13.8}Cu_{12.5}Ni_{10}Be_{22.5} and Zr_{58.5}Cu_{15.6}Ni_{12.8}Al_{10.3}Nb_{2.8}. Combining in situ synchrotron x-ray diffraction and quasielastic neutron scattering with electrostatic levitation, we directly observe an abrupt change in the temperature dependence of the first structure factor maximum of these melts. We find that the kinetics of this liquid-liquid transition during cooling are on the order of tens of seconds, whereas its onset temperature depends only weakly on the applied cooling rate. Such slow transition kinetics require long-range mass transport, which is incompatible with a transition mechanism involving only local structural changes as in oxides or molecular liquids.

Mercury and metal(loid) deposition to remote Nova Scotia lakes from both local and distant sources

Kejimkujik National Park, in Nova Scotia, Canada, is a sensitive region for metal(loid) contamination, such as mercury, in part due to long-range atmospheric deposition from global and regional industrial centers. The region is remote from industrial centres, but is downwind of major pollution sources in the Eastern United States and Canada, and historically had numerous gold mining sites. Due to a paucity of long-term atmospheric deposition monitoring in this region, little is known about the response of Kejimkujik lakes to multiple changing global, regional and local atmospheric Hg and metal(loid) sources. Here, we used multiple lake sediment cores to reconstruct anthropogenic depositional fluxes of metal(loid)s of concern for the last ~210years. Results showed that Kejimkujik lake sediments are highly enriched in lead (Pb), antimony (Sb) and tin (Sn), with post-industrial metal(loid) concentrations being >4-fold greater than natural baseline levels (prior to ~1800) and moderately enriched in silver (Ag), bismuth (Bi), cadmium (Cd), copper (Cu), mercury (Hg), rubidium (Rb), tellurium (Te), thallium (Tl), vanadium (V), tungsten (W) and zinc (Zn), with post-industrial metal(loid) concentrations being between 1.5 and 4-fold greater than natural baseline levels (prior to ~1800). Lake sediment core reconstructions of total atmospheric Hg deposition matched well with Hg wet deposition monitoring data from the overlapped period (1997-2010) being 9.1±2.7μg/m²/yr and 7.0±0.7μg/m²/yr respectively. Lakes closest to historic gold mining sites show spikes in Ag, Cd, Sb, Tl, Zn and W during mining periods (~1880 and 1950). Most of the enriched metal(loid)s (EF >1.5) (Ag, Bi, Cu, Hg, Pb, Sb, Sn, V and W) do not appear affected by redox and remobilisation issues. For the other enriched metal(loid)s (EF >1.5) (Cd, Tl, and Zn), remobilisation from upper sediments appears to be occurring within these acidic and DOC rich Kejimkujik lakes.

[Expanded flaps with vascular anastomosis for the treatment of scar contracture deformities of extensively burned patients]

Objective: To explore the effect of expanded flaps with vascular anastomosis in the treatment of scar contracture deformities of extensively burned patients. Methods: From April 2016 to February 2018, 9 patients with severe scar contracture deformities caused by extensive burns were hospitalized in our unit, including 7 males and 2 females, aged 23-54 years. There were 14 sites of scar contracture deformities and dysfunction, including 8 in face and neck, 2 in elbow, and 4 in wrist and hand. The expander was inserted into the chest or abdomen and was expanded by 2 to 3 times of its rated volume with injection of normal saline. After satisfied expansion, the expanded flap was harvested and transplanted with arteriovenous anastomosis onto the recipient site, where the scar was removed, the deformity was corrected, and the contracture was released. The number of expanders, the volume of normal saline injected, the period of expansion, the complications of skin and soft tissue expansion, the number, size, thickness, transplantation modes, and survival of flaps, and the repair method of donor site were observed and recorded. The reconstruction effect of scar contracture deformity was followed up. The patients' satisfaction with the therapeutic effect of various surgical sites during follow-up was investigated with a 5-point Likert Scale. The Burn Specific Health Scale-Brief was used to evaluate the quality of life of the patients pretreatment and during follow-up. Data were processed with paired sample t test or Wilcoxon signed-rank sum test. Results: A total of 16 expanders were inserted in this group of patients, including 6 in the chest and 10 in the abdomen. The volume of normal saline injected at the end of expansion was (1 421±348) mL. The expansion time was (8.1±2.6) months. One case of expander leakage and one case of injection port turnover resulted in failure of water injection occurred during expansion. Totally 17 flaps were resected from 16 expanded areas. The size of flaps ranged from 15 cm×13 cm to 30 cm×25 cm. The thickness was (0.49±0.06) cm in 6 chest flaps and (0.76±0.15) cm in 11 abdomen flaps. Free transplantation with vascular anastomosis was performed in 14 flaps, and pedicled transplantation supercharged with distal vascular anastomosis was performed in 3 flaps, one of which the vascular pedicle was divided and re-anastomosed to the other side of the recipient area 2 weeks later. Except for one donor site of abdomen flap which was transplanted with thin split-thickness scalp, the other donor sites were sutured directly. After operation, 2 flaps were slightly necrotic at the distal end and healed after dressing change and thin split-thickness scalp transplantation respectively, while the remaining 15 flaps all survived. During the follow-up of 6-24 months, the texture of the flaps was soft. The abdomen flap transplanted to the palm of hand in one patient was slightly hypertrophic, which was thinned 3 months after operation, while the other flaps were good in thickness. At the last follow-up, the appearance and function of the sites repaired by flaps of all patients were obviously improved compared with those before operation, the satisfaction score of the patients with the therapeutic effect of the surgical site was (4.4±0.6) points, the total score of quality of life and the scores of heat sensitivity, treatment antipathy, body image, and affect of patients were significantly higher than those before treatment (t=3.232, 2.683, 3.969, 2.884, 2.588, P<0.05), while the scores of hand function, sexuality, interpersonal relationship, simple function abilities, perception in returning to work of patients were close to those before treatment (t=0.778, 1.000, 1.664, Z=1.826, 1.633, P>0.05). Conclusions: Expanded flaps with vascular anastomosis are suitable for the treatment of scar contracture deformities of extensively burned patients. The flaps are large in size and suitable in thickness. The donor sites are easy to be closed directly. The treatment can obviously improve the appearance, function, and the quality of life of the patients, with a high satisfaction of patients.

Early warning method for cyanobacteria toxin, taste and odor problems by the evaluation of fluorescence signals

Permanganate and ozone are often used in drinking water treatment plants for the oxidation of taste and odor compounds, toxins, and algae as well as the reduction of mussel activity. The disadvantage of an overuse of such oxidants is the potential lysis of cyanobacterial cells. Cell lysis causes taste and odor components as well as toxins to be released into the water, which results in the need for even more treatment to remove these compounds completely. Our research in the CLIENT-SIGN project investigated an innovative method to monitor the lysis of cyanobacteria cells: increases in a specific fluorescence emission spectrum of the cyanobacteria pigment phycocyanin were used as a proxy for cell lysis and other compounds (taste/odor, toxins) leaving the cells. We call this form of phycocyanin "free phycocyanin" or "unbound phycocyanin". By monitoring free phycocyanin via a relatively fast and inexpensive measurement, water utilities will be better able to optimize the dosage of pre-oxidation compounds to remove extracellular compounds while preventing the lysing of cells. Laboratory studies and a case study at Yangcheng Lake (adjacent to Lake Taihu, Yangcheng Lake Water Treatment Plant, Suzhou Industrial Park, China) are presented herein. An online surveillance system that monitors incoming raw water and the water after pre-oxidation is proposed to better cope with changing water conditions.

Development of Cu-bearing powder metallurgy Ti alloys for biomedical applications

Cu-bearing Ti alloys could be used as structural biomedical materials where the releasing of Cu ions is beneficial to lower infection incidences associated with surgical implants. The manufacturing of these alloys via powder metallurgy techniques can lower the production costs. In this study three ternary Cu-bearing Ti-xAl-yCu alloys were produced using conventional powder metallurgy. The mechanical properties increase with the amount of alloying elements. Samples of each composition were also forged to clarify the effect of subjecting them to hot deformation. Forging the samples improved the strength of the alloys due to the reduction of porosity and the refinement of the microstructural features. It is found that Ti-2Al-1Cu is the most ductile, Ti-6Al-4Cu is the strongest and Ti-10Al-5Cu has a purely elastic behaviour. Some of these powder metallurgy Ti-xAl-yCu alloys have better overall mechanical behaviour than their cast counterparts and therefore are valuable alternative to produce medical and dental implants with improved properties and reduced cost.

Direct observation of magnetic contrast obtained by photoemission electron microscopy with deep ultra-violet laser excitation

Magnetic circular dichroism (MCD) and magnetic linear dichroism (MLD) have been investigated in a photoemission electron microscopy (PEEM) system excited by a deep ultra-violet (DUV) laser (with λ = 177.3 nm and hυ = 7.0 eV) for the first time. High resolution PEEM magnetic images (down to 43.2 nm) were directly obtained on a (001)-oriented magnetic FePt film surface with a circularly-polarized light under normal incidence. Furthermore, a stepped Cr seeding layer was applied to induce the formation of large-area epitaxial FePt films with (001) and (111) two orientations, where MLD with large asymmetry was observed in the transition area of two phases. It demonstrates that DUV laser can be a powerful source for high resolution magnetic imaging in the laboratory in absence of synchrotron facilities.

Karyotype, evolution and phylogenetic reconstruction in Micronycterinae bats with implications for the ancestral karyotype of Phyllostomidae

BACKGROUND

The Micronycterinae form a subfamily of leaf-nosed bats (Phyllostomidae) that contains the genera Lampronycteris Sanborn, 1949, and Micronycteris Gray, 1866 (stricto sensu), and is characterized by marked karyotypic variability and discrepancies in the phylogenetic relationships suggested by the molecular versus morphological data. In the present study, we investigated the chromosomal evolution of the Micronycterinae using classical cytogenetics and multidirectional chromosome painting with whole-chromosomes probes of Phyllostomus hastatus and Carollia brevicauda. Our goal was to perform comparative chromosome mapping between the genera of this subfamily and explore the potential for using chromosomal rearrangements as phylogenetic markers.

RESULTS

The Micronycterinae exhibit great inter- and intraspecific karyotype diversity, with large blocks of telomere-like sequences inserted within or adjacent to constitutive heterochromatin regions. The phylogenetic results generated from our chromosomal data revealed that the Micronycterinae hold a basal position in the phylogenetic tree of the Phyllostomidae. Molecular cytogenetic data confirmed that there is a low degree of karyotype similarity between Lampronycteris and Micronycteris specimens analyzed, indicating an absence of synapomorphic associations in Micronycterinae.

CONCLUSIONS

We herein confirm that karyotypic variability is present in subfamily Micronycterinae. We further report intraspecific variation and describe a new cytotype in M. megalotis. The cytogenetic data show that this group typically has large blocks of interstitial telomeric sequences that do not appear to be correlated with chromosomal rearrangement events. Phylogenetic analysis using chromosome data recovered the basal position for Micronycterinae, but did not demonstrate that it is a monophyletic lineage, due to the absence of common chromosomal synapomorphy between the genera. These findings may be related to an increase in the rate of chromosomal evolution during the time period that separates Lampronycteris from Micronycteris.

[Mortality trend and age-period-cohort analysis of colorectal cancer among residents in Yangpu District of Shanghai from 1975 to 2014]

Objective: To describe the 40-years trend for the mortality of colorectal cancer (CRC) in Shanghai and to estimate the effect of age, period, and birth cohort with Age-Period-Cohort (APC) model. Methods: Data on tumor-releated death from 1975 Janurary 1 to 2014 December 31 was derived from the Yangpu District of Shanghai Center for Diseases Prevention and Control tumor registration system. Colonrectal cancer cases (C18.2-C18.9 and C20 in ICD10) were selected for analyses. Crude mortality, age-adjusted mortality, and Average Annual Percent Changes (AAPCs) were calculated for colon cancer and rectal cancer. The difference of AAPCs between male/female and different age groups were tested. An APC model (reference cohort and period were 1900 and 1975, respectively) was constructed to estimate the age-effect, period-effect, and cohort-effect on the colorectal cancer death. Results: During 1975-2014, 6 725 cases died of colorectal cancer (the cased of colon and rectal cancer were 3 684 and 3 041, respectively). The crude mortality and age-adjusted mortality of colon cancer was 8.83/100 000 and 6.76/100 000, respectively. The crude mortality and age-adjusted mortality of rectal cancer were 7.32/100 000 and 5.67/100 000, respectively. For population in Yangpu District, the crude mortality and age-adjusted mortality of colon cancer increased with time, and the crude mortality of rectal cancer increased with time (P<0.001). AAPC of the crude mortality rate (5.6%) and age-adjusted mortality rate (2.3%) of colon cancer were higher than those in rectal cancer (3.0% and -0.3%), respectively (both P values <0.001). AAPC of the crude mortality rate (males vs. females was 6.2% vs. 5.0%, P<0.05) and age-adjusted mortality rate (males vs. females was 2.7% vs. 1.7%, P<0.05) of colon cancer were higher in males than in females. APC model indicted that CRC-related death increased with age. During 1901 to 1941, the RR values of cohort effects for colon and rectal cancer death were 1.09-5.57 and from 1.04-2.28, respectively; During 1946 to 1991, the RR values of cohort effects for colon cancer and rectal cancer were 5.51-4.32 and 2.16-0.89. Conclusion: From 1975 to 2014, the mortality of CRC in Yangpu District increased gradually, and colon cancer mortality in males increased faster than that in females. The risk of death from colorectal cancer in the 1946-1991 birth cohort declined.

Ligustilide, a major bioactive component of Angelica sinensis, promotes bone formation via the GPR30/EGFR pathway

Angelica sinensis (Oliv.) Diels is a widely-used traditional Chinese herbal medicine in treating osteoporosis. Ligustilide (LIG) is the main component of A. sinensis and is considered to be the most effective biologically active ingredient in this plant. LIG has been found to have multiple pharmacological activities, such as anti-atherosclerosis, neuroprotection, anticancer, anti-inflammatory and analgesic. However, little is known regarding its anti-osteoporotic effects. The aims of this study were to investigate any protective effect of LIG on bone formation. The results showed that LIG significantly ameliorated inhibition of bone formation in zebrafish caused by prednisolone. LIG promoted osteoblast differentiation, including that of the pre-osteoblastic cell line MC3T3-E1 and bone marrow mesenchymal stem cells. LIG greatly improved the viability of MC3T3-E1 cells exposed to H₂O₂, attenuated H₂O₂-induced apoptosis and increased the expression of Bcl-2. Furthermore, LIG treatment lead to marked activation of phosphorylated EGFR and ERK1/2. These effects could be obviously inhibited by blocking GPR30 signaling with the specific inhibitor G15. Collectively, the results reveal that GPR30 is a positive switch for LIG to increase bone formation via regulation of EGFR, and these results provide evidence for the potential of LIG to treat osteoporosis.

The SASE1 X-ray beam transport system

SASE1 is the first beamline of the European XFEL that became operational in 2017. It consists of the SASE1 undulator system, the beam transport system, and the two scientific experiment stations: Single Particles, Clusters, and Biomolecules and Serial Femtosecond Crystallography (SPB/SFX), and Femtosecond X-ray Experiments (FXE). The beam transport system comprises mirrors to offset and guide the beam to the instruments and a set of X-ray optical components to align, manipulate and diagnose the beam. The SASE1 beam transport system is described here in its initial configuration, and results and experiences from the first year of user operation are reported.

MicroRNA-32 inhibits the proliferation, migration and invasion of human colon cancer cell lines by targeting E2F transcription factor 5

OBJECTIVE

MicroRNAs to be essential therapeutic targets for the treatment of diseases such as cancer. Colon cancer is one of the prevalent cancers and causes tremendous human mortality. The treatment of colon cancer is limited by late diagnosis and lack of efficient therapeutic targets. Herein, the therapeutic potential of the miR-32 was explored in colon cancer.

PATIENTS AND METHODS

Expression analysis was carried out by quantitative Real-time polymerase chain reaction (qRT-PCR). Transfections were performed by Lipofectamine® 2000 reagent. The cell counting kit 8 (CCK-8) assay was used to determine cell viability. The 4', 6-diamidino-2-phenylindole (DAPI) and annexin V/Propidium Iodide (PI) assays were used for the detection of apoptosis. Transwell assays were used to determine cell migration and invasion. The expression of the proteins was estimated by Western blotting.

RESULTS

The results showed that the expression of miR-32 was aberrantly downregulated in all colon cancer cells. Overexpression of miR-32 caused significant (p<0.01) decline in the viability in SW-948 cells via induction of apoptosis. The induction of apoptosis was also accompanied by the upregulation of Bax and downregulation of Bcl-2 expression. Overexpression of miR-32 also caused the arrest of the SW-498 cells in the G2/M phase of cell cycle and inhibited their migration and invasion. TargetScan analysis showed E2F transcription factor 5 (E2F5) to be the potential target of miR-32, which was also confirmed by dual luciferase reporter assay. The expression of E2F5 was significantly (p<0.01) upregulated in the colon cancer cells and overexpression of miR-32 caused a considerable decline in the expression of E2F5 in the SW-948 cells. E2F5 silencing also inhibited the growth of the SW-948 cells via induction of apoptosis and G2/M cell cycle arrest. MiR-32 overexpression also inhibited the migration and invasion of the SW-948 cells. However, rescue assay revealed E2F5 to be essential for the tumor suppressive effects of miR-32.

CONCLUSIONS

The findings of the present study reveal that miR-32 acts as a tumor suppressor in colon cancer cells and may have therapeutic implications in colon cancer treatment.

Towards label-free distributed fiber hydrogen sensor with stimulated Raman spectroscopy

Hydrogen detection is of great importance in chemical and energy industries. Optical fiber hydrogen sensors show flexibility and compactness, and have the potential for distributed analysis. However, traditional fiber sensors encounter a challenge with light interacting with hydrogen directly because hydrogen only displays weak quadrupole absorption, and metallic palladium and platinum thin-film coatings are typically used as an optically detectable label. Here, based on stimulated Raman spectroscopy in hollow-core photonic crystal fibers, we investigate the label-free optical fiber distributed hydrogen sensors operating in the optical telecommunication band. The approach of distributed Raman measurement represents a new paradigm in fiber sensors, potentially allowing distributed chemical analysis in gas or liquid phase with high sensitivity and selectivity.

Low-cost powder metallurgy Ti-Cu alloys as a potential antibacterial material

Ti and Ti alloys are extensively used in biomedical applications due to their excellent biocompatibility and mechanical properties but their high-cost of production is still a limiting factor. It has been reported that the addition of Cu to Ti enables the creation of Ti alloys exhibiting antibacterial properties. Therefore, in this study Ti-Cu alloys (Cu = 0.5, 2.5 and 5 in wt.%) with potential antibacterial activity were fabricated by powder metallurgy (i.e. cold press and vacuum sintering) to reduce the production costs. As many biomaterials are employed as structural components, the Ti-Cu alloys were also subjected to β forging in order to improve their mechanical properties. It is found that the studied Ti-Cu alloys have superior mechanical properties to other commonly used Ti-based materials and are, thus, potential candidate for biomedical applications. Moreover, among the tested materials, the β forged Ti-5Cu alloys has tensile strength of 904 MPa, elongation of 6.7%, and Vickers hardness of 302 HV, which are comparable to those of the Ti-6Al-4V, and comprises the Ti₂Cu phase (confirmed by the XRD) as microstructural feature, which is fundamental to guarantee antibacterial properties.

[Hepatocellular carcinoma: co - evolution of hepatocytes and hepatitis B virus]

Chronic hepatitis B virus (HBV) infection is a major cause of hepatocellular carcinoma (HCC). In the process from chronic HBV infection to the development of HCC, there is a phenomenon of co-evolution of hepatocytes and HBV. The evolution of hepatocytes includes dedifferentiation and reverse evolution, while the evolution of HBV is mainly "telemorphosis" . Since HBV evolution occurs earlier than the development of HCC, the interaction between them is mainly reflected in the promotion of HCC evolution by HBV mutation. This article briefly summarizes the novel theory termed as cancer evolution and development and elucidates the molecular mechanism of HCC caused by HBV from the perspective of evolution.

[A study of bacterial distribution and drug resistance in skin and soft tissue infection]

Objective: To investigate pathogenic bacteria and drug resistance in the patients with skin and soft tissue infection in order to provide the scientific evidences for clinical reasonable use of antibiotics. Methods: A retrospective analysis was performed on patients with skin and soft tissue infections in Department of Dermatology, Peking University Third Hospital from January 2012 to December 2017. Pus, secretions, skin lesions, urine, throat swabs, and alveolar lavage fluid were collected for bacterial culture, bacterial species were identified by VITEK2 Compact system and BD-Bruker MALDI Biotyper system. Drug resistance was detected by K-B agar diffusion method recommended by CLSI. Results: A total of 392 strains of bacteria were isolated from 327 patients distributed in 21 genus and 56 species, of which 225 were gram-positive cocci (57.40%), 114 were gram-negative rods (29.08%), 46 were gram-positive rods (11.73%), and 7 were gram-negative cocci (1.79%). The top 3 bacteria were Staphylococcus aureus 91(23.21%), Staphylococcus epidermidis 42 (10.71%), and Pseudomonas aeruginosa 24 (6.12%). Staphylococcus had a high rate of resistance to penicillin and erythromycin (>50%). Gram-negative rods were resistant to ampicillin (86.1%), and also had certain resistance to most second-generation and some third-generation cephalosporin (about 50%). There was no significant change in the drug resistance rate of MRSA compared to MSSA. Only the resistance rate to tetracycline was statistically different (P<0.05). Conclusion: The emergence of drug-resistant strains is an important factor leading to refractory infections. There are a wide range of pathogenic bacteria species among the skin and soft tissue infection patients, and antimicrobial drugs should be chosen wisely according to drug sensitivity.

[Analysis on risk factors for norovirus outbreaks in Guangdong province, 2008-2015]

Objective: To analyze transmission factors of norovirus outbreaks in Guangdong province during 2008-2015 and provide evidence for the prevention and control of norovirus infection. Methods: Epidemiological analysis was performed on the data of norovirus outbreaks reported in Guangdong from January 1, 2008 to December 31, 2015, which were obtained from the Public Health Emergency Management Information System of Guangdong province. The samples collected from the norovirus outbreaks were detected for norovirus by RT-PCR and the gene sequencing of the positive PCR products were performed. Results: A total of 96 norovirus outbreaks were reported in Guangdong during 2008-2015. Sixteen outbreaks were reported during 2008-2012 and 80 outbreaks were reported during 2013-2015 (83.3%). Eighty-two outbreaks (85.4%) occurred in schools. The infection routes included foodborne transmission in 39 outbreaks (40.6%), person to person transmission in 23 outbreaks (24.0%) and waterborne transmission in 8 outbreaks (7.3%). The gene sequencing results showed that variant GⅡ.4/Sydney2012 was the predominant pathogen for 6 of the 20 outbreaks (30.0%) during 2012-2013. Variant GⅡ.17 was the predominant pathogens for 33 of the 53 outbreaks (62.3%) during 2014-2015. Conclusion: The norovirus outbreaks in Guangdong during 2008-2015 were caused by foodborne and person to person transmissions of two emerging variant: GⅡ.4/Sydney2012 and GⅡ.17.