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A method to grow few-layer graphene in the form of an “inverted pagoda” is proposed by controlling the pressure and the flow rate in a circulating chemical vapor deposition system. Such single-crystal few-layer graphene consists of one- to eight-layer graphene areas exhibiting layer growth characteristics. Moreover, each layer within this kind of few-layer graphene is in Bernal stacking. In this work, with increasing growth pressure, the self-limiting effect of graphene was successfully overcome, and the growth of graphene in the vertical direction was achieved. By controlling the ratio of H2/CH4, the morphology and the number of layers of the multilayer graphene under the single-layer graphene were modulated.

The combination of two-dimensional (2D) materials with non-2D materials (quantum dots, nanowires and bulk materials), i.e., mixed-dimensional van der Waals (md-vdW) heterostructures endow 2D materials with remarkable electronics properties. However, it remains a big challenge to synthesize md-vdW heterostructures because of the difference of crystal symmetry between 2D and non-2D materials. Meanwhile, it is difficult to initiate the nucleation due to the lack of chemical active sites on chemical inert surfaces of 2D materials. Herein, we design a general chemical vapor deposition (CVD) method for synthesizing a broad class of md-vdW heterostructures with well-aligned hexagonal symmetry including MoS2/FeS, MoS2/CoS, MoS2/MnS, MoS2/ZnS, Mo(SxSe1-x)2/ZnSxSe1-x,Mo(SxSe1-x)2/CdSxSe1-x. Combining with DFT calculation, we find that the hexagonal symmetry and the centered clusters of MoS2 and Mo(SxSe1-x)2 nanoflakes are two crucial factors to launch the hexagonally oriented growth and nucleation of non-2D materials on 2D materials. Our discovery opens an opportunity for the versatile hetero-integration of 2D materials and allows systematic investigation of physical properties in a wide variety of md-vdW heterostructures.

As an opportunistic pathogen worldwide, Staphylococcus aureus can cause food poisoning and human infections. This study investigated the sequence typing, the penicillin (blaZ) and methicillin (mec) resistance profiles of S. aureus from food samples and food poisoning outbreaks in Shijiazhuang City, and the staphylococcal enterotoxin (SE) types of the S. aureus isolates from food poisoning. A total of 138 foodborne S. aureus isolates were distributed into 8 clonal complexes (CCs) and 12 singletons. CC1, CC5, CC8, CC15, CC97, CC59, CC398, CC88, and CC7 were the predominant CCs of foodborne S. aureus isolates. Moreover, CC59, CC15, and CC5 were the most prevalent CCs in food poisoning outbreaks. SEE was the most commonly detected SE in food poisoning isolates. One hundred thirty-three S. aureus isolates harbored the penicillin-resistant gene blaZ, and nine isolates carried the mec gene. The present study further explained the relationship between S. aureus and foods and food poisoning and indicated the potential risk of S. aureus infection.

Pedestrian detection and re-identification technology is a research hotspot in the field of computer vision. This technology currently has issues such as insufficient pedestrian expression ability, occlusion, diverse pedestrian attitude, and difficulty of small-scale pedestrian detection. In this paper, we proposed an end-to-end pedestrian detection and re-identification model in real scenes, which can effectively solve these problems. In our model, the original images are processed with a non-overlapped image blocking data augmentation method, and then input them into the YOLOv3 detector to obtain the object position information. LCNN-based pedestrian re-identification model is used to extract the features of the object. Furthermore, the eigenvectors of the object and the detected pedestrians are calculated, and the similarity between them are used to determine whether they can be marked as target pedestrians. Our method is lightweight and end-to-end, which can be applied to the real scenes.

Altres ajuts: This study has been supported by Spanish Ministry of Science and Innovation, Sociedad Española de Neumología y Cirugía Torácica (SEPAR) 2018 & 2020. Lung cancer (LC) risk increases in patients with chronic respiratory diseases (COPD). MicroRNAs and redox imbalance are involved in lung tumorigenesis in COPD patients. Whether systemic alterations of those events may also take place in LC patients remains unknown. Our objectives were to assess the plasma levels of microRNAs, redox balance, and cytokines in LC patients with/without COPD. MicroRNAs (RT-PCR) involved in LC, oxidized DNA, MDA-protein adducts, GSH, TEAC, VEGF, and TGF-beta (ELISA) were quantified in plasma samples from non-LC controls (n = 45), LC-only patients (n = 32), and LC-COPD patients (n = 91). In LC-COPD patients compared to controls and LC-only, MDA-protein adduct levels increased, while those of GSH decreased, and two patterns of plasma microRNA were detected. In both LC patient groups, miR-451 expression was downregulated, while those of microRNA-let7c were upregulated, and levels of TEAC and TGF-beta increased compared to the controls. Correlations were found between clinical and biological variables. A differential expression profile of microRNAs was detected in patients with LC. Moreover, in LC patients with COPD, plasma oxidative stress levels increased, whereas those of GSH declined. Systemic oxidative and antioxidant markers are differentially expressed in LC patients with respiratory diseases, thus implying its contribution to the pathogenesis of tumorigenesis in these patients.

Whether the COVID-19 pandemic may have modified the clinical planning and course in bronchiectasis patients remains to be fully elucidated. We hypothesized that the COVID-19 pandemic may have influenced the management and clinical outcomes of bronchiectasis patients who were followed up for 12 months. In bronchiectasis patients (n = 30, 23 females, 66 years), lung function testing, disease severity [FEV1, age, colonization, radiological extension, dyspnea (FACED), exacerbation (EFACED)] and dyspnea scores, exacerbation numbers and hospitalizations, body composition, sputum microbiology, and blood analytical biomarkers were determined at baseline and after a one-year follow-up. Compared to baseline (n = 27, three patients dropped out), in bronchiectasis patients, a significant increase in FACED and EFACED scores, number of exacerbations, and erythrocyte sedimentation rate (ESR) was observed, while FEV1, ceruloplasmin, IgE, IgG, IgG aspergillus, IgM, and IgA significantly decreased. Patients presenting colonization by Pseudomonas aeruginosa (PA) remained unchanged (27%) during follow-up. In bronchiectasis patients, FEV1 declined only after a one-year follow-up along with increased exacerbation numbers and disease severity scores, but not hospitalizations. However, a significant decrease in acute phase-reactants and immunoglobulins was observed at the one-year follow-up compared to baseline. Despite the relatively small cohort, the reported findings suggest that lung function impairment may not rely entirely on the patients’ inflammatory status.

Immune microenvironment plays a role in the development of lung cancer (LC). We hypothesized that immune profile of B and T cells may differ in tumors of LC patients with and without COPD and may also influence survival. Objectives: 1) To analyze levels of tertiary lymphoid structures (TLSs), B and T cells in tumor and non-tumor (control samples) lung specimens of LC patients with/without COPD and 2) to analyze the influence of those biological markers in the patients´10-year survival. TLSs (numbers and area), B (CD20), and T (CD3) cells were identified in both tumor and non-tumor specimens (thoracotomy) from 90 LC-COPD patients and 43 LC-only patients (immunohistochemistry). Survival was analyzed in all 133 patients. Immune profile in tumors of LC-COPD versus LC: The number of TLSs significantly decreased in tumors of LC-COPD compared to LC patients. No significant differences were observed in tumors between LC-COPD and LC for B or T cells. In tumors compared to non-tumor specimens, a significant rise in TLSs was observed in LC (numbers and area) and LC-COPD (area), T cell counts declined in tumors of LC, while B cell counts increased in tumors of both LC and LC-COPD patients. Survival: In LC-COPD patients: lower numbers of TLSs and greater numbers of B cells were associated with worse survival. In LC patients: lower levels of T cells were associated with longer survival rates. TLSs, B cells and T cells are differentially expressed in tumors of LC-COPD from that in LC-only patients. Method: FIS 18/00075 & CIBERES (FEDER, ISC-III), SEPAR 2018, unrestricted research grant from Menarini SA 2018.

Background: The immune microenvironment plays a role in tumorigenesis. Chronic Obstructive Pulmonary Disease (COPD) is an independent risk factor for lung cancer (LC). We hypothesized that immune profile characterized by T regulatory (Treg), natural killer (NK), and plasma cells, as well as interleukin (IL)-10 and interferon-gamma, may differ within tumors of LC patients with/without COPD. Methods: Treg (anti-CD3 and anti-forkhead boxP3 antibodies), NK (anti-NCR1 antibody), IgG (anti-CD138-IgG antibody), IgA (anti-CD138-IgA antibody) using immunohistochemistry, and both IL-10 and interferon-gamma (ELISA) were quantified in tumor and non-tumor specimens (thoracotomy for lung tumor resection) from 33 LC&ndash, COPD patients and 20 LC-only patients. Results: Immune profile in tumor versus non-tumor specimens: Treg cell counts significantly increased in tumors of both LC and LC&ndash, COPD patients, while in tumors of the latter group, IgG-secreting plasma cells significantly decreased and IL-10 increased. No significant differences were seen in levels of NK cells, IgA-secreting cells, IgA/IgG, or interferon-gamma. Immune profile in tumors of LC&ndash, COPD versus LC: No significant differences were observed in tumors between LC&ndash, COPD and LC patients for any study marker. Conclusions: Immune cell subtypes and cytokines are differentially expressed in lung tumors, and the presence of COPD elicited a decline in IgG-secreting plasma cell levels but not in other cell types.

In order to reduce wear and design high-performance spline coupling, the friction coefficient, wear coefficient, and wear depth of 14 groups of material specimens were tested using multifunctional friction and wear tester. The effect of materials, loads, rotation speed, and surface treatment on friction coefficient, wear coefficient, and wear depth was investigated. A method using an Archard’s equation based on the finite element method to calculate the wear depth of 14 groups of material specimens was proposed, and the results were consistent with the experimental results. Then, the wear of a floating involute spline coupling of aero-engine was predicted using this method. It can be concluded that carburizing and silvering can decrease the friction coefficient. The wear and wear coefficient decreased after carburizing. So, it is necessary to take 18CrNi4A with carburization and 32Cr3MoVA with nitridation as the material of the spline coupling in aero-engine to minimize wear. Furthermore, the method presented to predicate the wear of spline coupling in this work provided a good fundament for the fatigue prediction methodology of spline coupling.

Immune profile of B and T cells and tertiary lymphoid structures (TLSs) may differ in tumors of lung cancer (LC) patients with/without chronic obstructive pulmonary disease (COPD), and may also influence patient survival. We sought to analyze: (1) TLSs, germinal centers (GCs), B and T cells, and (2) associations of the immune biomarkers with the patients&rsquo, 10-year overall survival (OS). TLSs (numbers and area), B [cluster of differentiation (CD) 20], and T (CD3), and GCs cells were identified in both tumor and non-tumor specimens (thoracotomy) from 90 LC-COPD patients and 43 LC-only patients. Ten-year OS was analyzed in the patients. Immune profile in tumors of LC-COPD versus LC: TLS numbers and areas significantly decreased in tumors of LC-COPD compared to LC patients. No significant differences were observed in tumors between LC-COPD and LC patients for B or T cells. Immune profile in tumors versus non-tumor specimens: TLS areas and B cells significantly increased, T cells significantly decreased in tumors of both LC and LC-COPD patients. Survival: in LC-COPD patients: greater area of TLSs and proportion of B cells were associated with longer survival rates. The immune tumor microenvironment differs in patients with underlying COPD and these different phenotypes may eventually impact the response to immunotherapy in patients with LC.

Citrobacter spp. are opportunistic human pathogens which can cause nosocomial infections, sporadic infections and outbreaks. In order to determine the genetic diversity, in vitro virulence properties and antimicrobial resistance profiles of Citrobacter spp., 128 Citrobacter isolates obtained from human diarrheal patients, foods and environment were assessed by multilocus sequence typing (MLST), antimicrobial susceptibility testing and adhesion and cytotoxicity testing to HEp-2 cells. The 128 Citrobacter isolates were typed into 123 sequence types (STs) of which 101 were novel STs, and these STs were divided into five lineages. Lineages I and II contained C. freundii isolates, Lineage III contained all C. braakii isolates, while Lineage IV and V contained C. youngae isolates. Lineages II and V contained more adhesive and cytotoxic isolates than Lineages I, III, and IV. Fifty-one of the 128 isolates were found to be multidrug-resistant (MDR, &ge, 3) and mainly distributed in Lineages I, II, and III. The prevalence of quinolone resistance varied with Lineage III (C. braakii) having the highest proportion of resistant isolates (52.6%), followed by Lineage I (C. freundii) with 23.7%. Seven qnrB variants, including two new alleles (qnrB93 and qnrB94) were found with Lineage I being the main reservoir. In summary, highly cytotoxic MDR isolates from diarrheal patients may increase the risk of severe disease.

This study aimed to assess the frequency of Klebsiella pneumoniae in food samples and to detect antibiotic resistance phenotypes, antimicrobial resistance genes and the molecular subtypes of the recovered isolates. A total of 998 food samples were collected, and 99 (9.9%) K. pneumoniae strains were isolated; the frequencies were 8.2% (4/49) in fresh raw seafood, 13.8% (26/188) in fresh raw chicken, 11.4% (34/297) in frozen raw food and 7.5% (35/464) in cooked food samples. Antimicrobial resistance was observed against 16 antimicrobials. The highest resistance rate was observed for ampicillin (92.3%), followed by tetracycline (31.3%), trimethoprim-sulfamethoxazole (18.2%), and chloramphenicol (10.1%). Two K. pneumoniae strains were identified as extended-spectrum β-lactamase (ESBL)-one strain had three beta-lactamases genes (blaSHV, blaCTX-M-1, and blaCTX-M-10) and one had only the blaSHV gene. Nineteen multidrug-resistant (MDR) strains were detected; the percentage of MDR strains in fresh raw chicken samples was significantly higher than in other sample types (P

With diagnosis tools' help, people analyze the yield problem and identify the process issues and finally improve production yield rate. Nowadays, this approach is often employed during products initial ramping up stage in foundry and large chip design house. It is not often to see that people apply diagnosis-driven analysis for matured products, capture the root causes, especially after wafer foundry confirmed their process control within target. We would like to introduce a case study for matured SoC product low yield analysis. With scan diagnosis and layout aware diagnosis, we apply all possible analysis and identify FA candidates for PFA (physical failure analysis), then capture process issues, and then finally enhance the yield with foundry process control. As a result for evidence captured, wafer foundry gives the compensation for the yield loss due to process control leak.

Based on the practice teaching, fully integrate with the experience in the process of teaching, the students' feedback about the teaching mode as well, also with the help from analysis and research, we studied the application of interactive teaching in "transportation and distribution management" course, further enriched the teaching content, emphasizing "the three a model of interaction between teacher and student, among students and that between school and enterprise". Meanwhile, according to the problem existed in the "transportation and distribution management" course, some specific interactive measures was put forward, such as, the current database, situational teaching and promote the interaction between school and enterprise. KEYWORD: Interactive Teaching Mode; Transportation and Distribution Management; Current Database; Situational Teaching

Cronobacter spp. (Enterobacter sakazakii) are important foodborne pathogens. Infections with this pathogen can lead to neonatal meningitis, necrotizing enterocolitis, and bacteremia. This study examined Cronobacter spp. contamination in commercial powdered infant formulas (PIFs) and follow-up formulas (FUFs) in China. Forty-nine of 399 samples were contaminated with Cronobacter spp. and 10.2% of the isolates were resistant to cefotaxime; in contrast, all of the tested isolates were susceptible to amikacin, amoxicillin/clavulanic acid, cefepime, ciprofloxacin, imipenem, and meropenem. Pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) analyses produced a total of 16 PFGE banding patterns and 11 sequence types (STs), including 7 novel STs. In summary, the rates at which Cronobacter spp. were isolated from commercial PIF and FUF samples in China were relatively high, and the isolated strains exhibited high susceptibility in vitro to most antibiotics. The PFGE method exhibited higher typing capability than the MLST method, and molecular typing results revealed that the contamination of PIF and FUF with Cronobacter spp. in China may be mainly due to the addition of contaminated materials. Thus, the development of more effective control strategies during the manufacturing process is needed.

Staphylococcus aureus is an opportunistic pathogen commonly identified from food poisoning–associated foodstuffs. From 1996 to the present, S. aureus isolates have been found to exhibit increasing resistance to antimicrobial drugs. The aim of this study was to assess the molecular epidemiology properties of various S. aureus isolates through molecular typing and to investigate their characterization based on their production of enterotoxins and hemolysins and their resistance to antibiotics. A total of 78 coagulase-positive staphylococcal strains isolated from food or clinical samples were analyzed. Eight VNTR loci were used to genotype the 78 isolates, and this analysis resulted in 39 different multilocus variable number tandem repeat analysis (MLVA) profiles. The isolates recovered from a single outbreak exhibited the same MLVA profile. According to CLSI, 97.4% of the isolates were resistant to penicillin, whereas only 3.8% were methicillin-resistant Staphylococcus aureus strains. Through multiplex PCR, 87.2% of the isolates were shown to be enterotoxigenic (SEs), and the most common genes present were sea , sem , seg , seu , and sek . In conclusion, this study demonstrates the prevalence of staphylococcal enterotoxins, the contents of virulent factors, and the characteristics of β-lactam antibiotic resistance in 78 S. aureus isolates. These findings emphasize the need to prevent the presence of S. aureus strains and SE production in foods. Our results also demonstrate that MLVA is a useful and powerful method for epidemiological studies of S. aureus . In contrast to multilocus sequence typing, the MLVA method is a simpler and more rapid method for epidemiological typing with a higher discriminatory power.