Development and validation of an individualized nomogram to identify occult peritoneal metastasis in patients with advanced gastric cancer

Background

Occult peritoneal metastasis (PM) in advanced gastric cancer (AGC) patients is highly possible to be missed on computed tomography (CT) images. Patients with occult PMs are subject to late detection or even improper surgical treatment. We therefore aimed to develop a radiomic nomogram to preoperatively identify occult PMs in AGC patients.

Patients and methods

A total of 554 AGC patients from 4 centers were divided into 1 training, 1 internal validation, and 2 external validation cohorts. All patients’ PM status was firstly diagnosed as negative by CT, but later confirmed by laparoscopy (PM-positive n = 122, PM-negative n = 432). Radiomic signatures reflecting phenotypes of the primary tumor (RS1) and peritoneum region (RS2) were built as predictors of PM from 266 quantitative image features. Individualized nomograms of PM status incorporating RS1, RS2, or clinical factors were developed and evaluated regarding prediction ability.

Results

RS1, RS2, and Lauren type were significant predictors of occult PM (all P < 0.05). A nomogram of these three factors demonstrated better diagnostic accuracy than the model with RS1, RS2, or clinical factors alone (all net reclassification improvement P < 0.05). The area under curve yielded was 0.958 [95% confidence interval (CI) 0.923–0.993], 0.941 (95% CI 0.904–0.977), 0.928 (95% CI 0.886–0.971), and 0.920 (95% CI 0.862–0.978) for the training, internal, and two external validation cohorts, respectively. Stratification analysis showed that this nomogram had potential generalization ability.

Conclusion

CT phenotypes of both primary tumor and nearby peritoneum are significantly associated with occult PM status. A nomogram of these CT phenotypes and Lauren type has an excellent prediction ability of occult PM, and may have significant clinical implications on early detection of occult PM for AGC.

Low Voltage Graphene-Based Amplitude Modulator for High Efficiency Terahertz Modulation

In this paper, a high-efficiency terahertz amplitude modulation device based on a field-effect transistor has been proposed. The polarization insensitive modulator is designed to achieve a maximum experimental modulation depth of about 53% within 5 V of gate voltages using monolayer graphene. Moreover, the manufacturing processes are inexpensive. Two methods are adopted to improve modulation performance. For one thing, the metal metamaterial designed can effectively enhance the electromagnetic field near single-layer graphene and therefore greatly promote the graphene’s modulation ability in terahertz. For another, polyethylene oxide-based electrolytes (PEO:LiClO₄) acts as a high-capacity donor, which makes it possible to dope single-layer graphene at a relatively low voltage.

[Exploration of potential beneficial people of neoadjuvant chemotherapy based on clinical staging in gastric cancer: a single center retrospective study]

Objective: To evaluate the accuracy of the clinical staging by comparing preoperative clinical stage and pathological stage in gastric cancer patients, and to explore the potential beneficial population of neoadjuvant chemotherapy for gastric cancer. Methods: We retrospectively collected the clinical data of consecutive patients with gastric cancer who met the inclusion criteria (gastric adenocarcinoma, undergoing laparoscopic or open D2 radical operation, definite cTNM and pTNM) for admission of the Gastrointestinal Center of Peking University Cancer Hospital from July 2013 to April 2019. Patients with the number of harvested lymph nodes less than 16, history of gastric operation or preoperative radiochemotherapy were excluded. Preoperative clinical stage was obtained from abdominal and pelvic enhanced CT by radiologists, and postoperative pathological stage was derived from postoperative pathology reports. The concordance rate between preoperative clinical stage and postoperative pathological stage, and the proportion of pathological stage I in patients with specific preoperative clinical TNM stage were analyzed and compared. The potential beneficial population of neoadjuvant chemotherapy were considered as pI < 5%. Relationship between clinical features and concordance rate of stage was further analysed. Results: A total of 459 patients were included in the analysis, including 321 males and 138 females with mean age of 60 (23 to 85) years old. The concordance rate from T1 to T4 between preoperative clinical T staging and postoperative pathological T staging was 82.5% (33/40), 31.1% (28/90), 34.4% (62/180), and 55.0% (96/149), respectively. The concordance rate from N0 to N3 between preoperative clinical N staging and postoperative pathological N staging was 58.8% (134/228), 22.1% (19/86), 23.6% (26/110), and 54.3% (19/35), respectively. The sensitivity and specificity of abdominal enhanced CT in the diagnosis of lymph node metastasis were 64.5% (171/265) and 69.1% (134/194) respectively. The clinical stage of cT3/T4 patients with pathological stage I was 9.1% (30/329), and the sensitivity of corresponding pathological stage III was 94.8% (164/173), while the cT3/4+cN1-3 patients with pathological stage I stage was 1.4% (3/218), and the sensitivity of corresponding pathological phase III was 76.9% (133/173). Tumor location was associated with the concordance of cT/pT staging [gastroesophageal junction: 64 (56.6%), upper stomach: 9 (9/17), middle stomach: 31 (40.3%), lower stomach: 97 (39.9%), whole stomach: 4(4/9), χ(2)=9.845, P=0.043]; the degree of tumor differentiation was associated with the concordance of cN/pN staging [poorly differentiated: 94 (42.3%), moderated differentiated: 92 (41.1%), well differentiated: 12 (12/13), χ(2)=13.261, P=0.001], whose differences were statistically significant (all P<0.05). Conclusion: Based on a single-center retrospective data from Peking University Cancer Hospital, we think that the potential beneficial population of neoadjuvant chemotherapy for gastric cancer are those clinically staged as cT3/4+N1-3.

Enhancement of the Photoresponse of Monolayer MoS2 Photodetectors Induced by a Nanoparticle Grating

Photodetectors based on two-dimensional (2D) materials such as monolayer MoS₂ are attractive because they can be directly integrated into the current metal-oxide semiconductor (CMOS) structures. Unfortunately, such devices suffer from low responsivity due to low absorption by the monolayer MoS₂. Combining MoS₂ with plasmonic nanostructures is an alternative solution for enhancing the absorption of the 2D semiconductor, and this can drastically increase the photoresponsivity of the corresponding photodetector. Herein, a device incorporating a grating-patterned nanoparticle structure is fabricated using traditional photolithography together with an annealing step. We demonstrate that this new structure leads to a strong enhancement in the photocurrent due to the coupling of the MoS₂ to localized surface plasmons in the nanoparticle grating. Compared to a simple Au nanoparticle array, the nanoparticle grating structure generates a 100% increase in optical absorption. Thus, under 532 nm illumination, the composite nanoparticle grating/monolayer MoS₂ integrated photodetector shows a 111-fold increase in the photocurrent compared to the same device in the absence of nanoparticles. The gateless responsivity can be up to 38.57 A/W and a specific detectivity of 9.89 × 10⁹ Jones is realized. Moreover, photothermal flux derivations indicate that, in addition to the expected increase due to light-generated carrier multiplication, the thermal effects of plasmons provide a significant contribution to the photocurrent enhancement.

Abstract TS1-2: Proteogenomic Landscape of Prospectively Collected Breast Cancer

A persistent central deficiency in our knowledge of cancer concerns how genomic changes drive the proteome and phosphoproteome to execute phenotypic characteristics. Furthermore increasing evidence implicating epigenetic and post-translational changes in cancer biology reinforce the notion that molecular profiles based on nucleic acids are incomplete and are critically complemented by analyses of proteins and their post-translational modifications. We present the first integrated proteogenomic study on a prospectively collected breast cancer cohort, and provide new insights including on taxonomy, metabolic dependencies, and immune milieu. 122 invasive ductal breast cancer samples were collected under the auspices of the National Cancer Institute’s Clinical Proteomics Tumor Analysis Consortium using rigorous protocols to minimize ischemic time and other pre-analytical variability. Samples underwent comprehensive genomic and proteomic characterization, providing whole exome, whole genome, copy number, RNAseq, global proteome, phosphoproteome, and acetylome data. Multi-omics clustering by nonnegative matrix factorization revealed basal-, luminal A-, and HER2-enriched clusters, as well as a combined luminal A/B cluster. Luminal A and A/B clusters were distinguished by differential expression of cytoskeletal signatures possibly driven by YAP1 overexpression and hyper-phosphorylation in the luminal A subset. Kinase outlier analysis revealed luminal A enrichment of PEAK1, an atypical kinase that regulates YAP1 expression. PTPN2, recently shown to synergize with anti-PD1 therapy, was an outlier in basal tumors, suggesting therapeutic opportunities in that difficult-to-treat subtype. Acetylation plays a dominant role in mitochondrial metabolism, and downregulation of deacetylase SIRT3 in basal and HER2-enriched samples was associated with upregulation of TCA cycle- and amino acid metabolism-related proteins suggesting metabolic dependencies that could be exploited. Immunological subtyping of the breast cohort identified immune-cold, immune-hot, immune-excluded and interferon-independent clusters associated with distinct patterns of tumor-infiltrating lymphocytes. Basal tumors generally overexpressed PDL1 relative to other subtypes, whereas the newly described immuno-oncology target SIGLEC15 was overexpressed in luminal tumors. While these and other analyses are intended to provide new insights into breast cancer biology and facilitate testable therapeutic hypotheses, the larger purpose of the program is to provide a resource to the breast cancer and broader scientific communities. To facilitate this, these and previously published data will be integrated to provide a sample set of 199 proteogenomically characterized breast cancers for further exploration.

Citation Format: M Gillette, K Krug, S Satpathy, E Jaehnig, A Karpova, K Clauser, L Tang, L Blumenberg, R Kothadia, K Ruggles, B Zhang, L Ding, P Mertins, DR Mani, M Ellis, S Carr. Proteogenomic Landscape of Prospectively Collected Breast Cancer [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr TS1-2.

Isolation and characterization of Streptococcus suis strains from swine in Jiangsu province, China

AIMS

The aim of this study is to investigate Streptococcus suis strains present in Jiangsu province, China.

METHODS AND RESULTS

In all, 1650 nasal and anal swab samples and 100 tonsils were collected from clinically healthy swine. Culture characteristics, colony morphology and PCR-based analysis of the glutamate dehydrogenase (gdh) gene were performed for S. suis identification, and eight isolates were confirmed to be S. suis. The isolates serogroups were identified by agglutinating test, including 4, 7, 3, 5 and 8. Gene profiling by PCR showed that the manN, purD, orf2, gdh genes were conserved among the isolates and that 50% of the isolates carried dltA, pgdA, srtA and sspA. Antimicrobial susceptibility test showed the isolates displayed resistance to clindamycin, erythromycin, tetracycline, penicillin G, vancomycin and linezolid; while none was resistant to chloramphenicol, multi-drug resistance was seen in most of the isolates. Finally, the LD₅₀ (assessed by zebrafish) of isolates RD105 was 2·6431 × 10⁵ and HA24 was 7·1198 × 10⁶ , which showed RD105 more virulent and was consistent with the results of virulence factor identification.

CONCLUSIONS

There is a very low proportion of S. suis in the healthy pigs. The virulence factors were related to pathogenicity. Bacteria in Nantong possess greater virulence potential than those in Huaian.

SIGNIFICANCE AND IMPACT OF THE STUDY

Systematic investigation of S. suis provided the most basic theoretical support for the prevention and control of swine streptococcosis.

Development of interatomic potential for Al–Tb alloys using a deep neural network learning method

The developed deep neural network (DNN) potential can describe the structural properties of the Al₉₀Tb₁₀ liquid and the formation energies of Al–Tb crystals with the accuracy of ab initio calculations.

[The clinical observation of serum specific biomarkers in patients with chronic graft-versus-host disease]

目的

研究异基因造血干细胞移植后患者血清生物标志物表达水平对慢性移植物抗宿主病（cGVHD）早期诊断的价值。

方法

采用液相悬浮芯片法检测接受异基因造血干细胞移植后发生和未发生cGVHD患者5种血清蛋白标志物（IL-1b、IL-16、CXCL9、CCL19、CCL17）表达水平。

结果

相较于未发生cGVHD的对照组，cGVHD患者血清中CXCL9、CCL17表达水平显著升高（P<0.05），其中CCL17与cGVHD的疾病严重程度相关（P<0.001）；CXCL9在皮肤损害的cGVHD患者血清中显著升高（P<0.01），CCL17在肝脏为靶器官的cGVHD患者中表达水平显著升高（P<0.01）。

结论

CXCL9联合CCL17可作为cGVHD的血清生物标志物，对辅助cGVHD诊断和评估严重程度有一定参考价值。

Characterization of peripheral blood mononuclear cells isolated using two kinds of leukocyte filters

OBJECTIVE

The objective of this study was to compare the activity and biological function of leukocytes isolated using apheresis platelet leukoreduction system chambers (LRSC), whole blood leukoreduction filters (LRF), and leukocytes in unfiltered peripheral whole blood (WB).

METHODS

Peripheral blood mononuclear cells (PBMCs) and granulocytes were obtained by density gradient centrifugation using recovery filters and WB. Flow cytometry was used to detect the activity, phenotype, and apoptosis ratio of each cell subtype.

RESULTS

The proportion of lymphocytes obtained from PBMCs was similar when using the two different filters as compared to traditional isolation; however, there were significant differences between the monocytes and granulocytes. The phenotypic frequency of lymphocytes was similar, but the apoptosis rate of lymphocytes from the two filters was slightly higher. Additionally, monocytes isolated via the three sources were able to be induced into dendritic cells expressing specific molecules; Granulocytes isolated from the LRF showed a lower purity and a higher level of apoptosis than granulocytes isolated from the WB.

CONCLUSION

Compared with WB, the PBMCs isolated from the filters used in our blood center had no statistical difference in their activity and biological function, but they did differ in the proportion and quantity of monocytes and granulocytes. Our results show that the two filters can be used as an alternative method to collect leukocytes, which solves the problem of an insufficient blood supply for clinical and basic science research. Thus, these filters have significant value beyond their practical use in clinics.

MiR-155 affects osteosarcoma cell proliferation and invasion through regulating NF-κB signaling pathway

OBJECTIVE

Osteosarcoma can form tumor osteoid tissue and bone tissue directly or indirectly through cartilage stage. It mainly occurs in children and adolescents with high mortality. MicroRNA (miRNA) possesses tissue sensitivity as tumor biomarker and plays a promoting or inhibitory role in tumor pathogenesis as oncogene or tumor suppressor gene. It was found that miR-155 was abnormally expressed in tumor and could be treated as a biomarker for cancer progression. However, miR-155 expression in osteosarcoma and related mechanism still remains unclear. This study aimed to explore the role of miR-155 in osteosarcoma occurrence and development.

MATERIALS AND METHODS

Osteosarcoma cell line MG-63 was cultured in vitro and transfected by miR-155 mimics or inhibitor. MiR-155 expression was examined by Real-time PCR (RT-PCR). Cell proliferation was evaluated by MTT assay. Caspase 3 activity was determined by caspase 3 activity detection kit. Cell invasion was measured by transwell assay. B-cell lymphoma-2 (Bcl-2) and nuclear factor κB (NF-κB) protein expressions were assessed by Western blot.

RESULTS

MiR-155 mimics significantly up-regulated miR-155 expression, promoted MG-63 cell proliferation and invasion, inhibited caspase 3 activity, and up-regulated expressions of NF-κB and Bcl-2 compared with control group (p < 0.05). However, miR-155 inhibitor significantly inhibited MG-63 cell proliferation and invasion, enhanced caspase 3 activity, and reduced expressions of NF-κB and Bcl-2 compared with control group (p < 0.05).

CONCLUSIONS

MiR-155 affected osteosarcoma cell proliferation and apoptosis through regulating NF-κB signaling pathway, indicating it might be a new biomarker for osteosarcoma diagnosis and treatment.

LncRNA SNHG7 promotes development of breast cancer by regulating microRNA-186

OBJECTIVE

To elucidate the biological functions of long non-coding RNA (lncRNA) SNHG7 in breast cancer (BC), and its underlying mechanism in the occurrence and progression of BC.

PATIENTS AND METHODS

The expression of SNHG7 in 72 pairs of BC tissues and paracancerous tissues was detected by quantitative Real-time polymerase chain reaction (qRT-PCR). Correlation between SNHG7 expressions with pathological indicators of BC patients was analyzed. Similarly, SNHG7 expression in BC cell lines was determined by qRT-PCR as well. After constructing the small inference RNA of SNHG7, cell proliferation, migration and invasion were determined by cell counting kit-8 (CCK-8), 5-Ethynyl-2'-deoxyuridine (EdU) and transwell assay. MicroRNA-186 expression in BC tissues and cells was accessed. Dual-luciferase reporter gene assay was conducted to verify the binding condition between SNHG7 and microRNA-186.

RESULTS

SNHG7 expression was higher in BC tissues than that of paracancerous tissues. High expression of SNHG7 was positively correlated to tumor stage, lymph node metastasis and distant metastasis, whereas not correlated to age, sex and tumor location of BC. Kaplan-Meier curves revealed that higher expression of SNHG7 is correlated to the worse prognosis of BC patients. SNHG7 was highly expressed in BC cells as well. Knockdown of SNHG7 inhibited proliferative, invasive and migratory abilities of BC cells. QRT-PCR data showed that microRNA-186 is lowly expressed in BC tissues compared with that of paracancerous tissues. MicroRNA-186 was lowly expressed in BC cells as well. Both mRNA and protein levels of microRNA-186 were negatively correlated to SNHG7 in BC tissues. Finally, the dual-luciferase reporter gene assay demonstrated that SNHG7 could be directly targeted by microRNA-186.

CONCLUSIONS

SNHG7 is highly expressed in BC, which is correlated to tumor stage, lymph node metastasis and distant metastasis of BC patients. SNHG7 could promote malignant progression of BC by regulating microRNA-186.

Inhibition of microRNA-218 promotes oral squamous cell carcinoma growth by targeting GLUT1 to affect glucose metabolism

OBJECTIVE

Glucose transporter 1 (GLUT1) is a key player in glucose metabolism that has important roles in oral squamous cell carcinoma (OSCC), while microRNA-218 can target GLUT1 to achieve its biological roles. Therefore, we hypothesize that microRNA-218 may target GLUT1 to participate in OSCC.

PATIENTS AND METHODS

Tumor tissues and adjacent healthy tissues were collected from OSCC patients, and blood samples were collected from both OSCC patients and healthy controls. Expression of microRNA-218 and GLUT1 in those tissues was detected by qRT-PCR. All patients were followed up for 5 years. Diagnostic and prognostic values of serum microRNA-218 for OSCC were investigated by ROC curve analysis and survival curve analysis, respectively. MicroRNA-218 knockdown OSCC cell lines were established. The effects on cell proliferation, glucose uptake as well as GLUT1 expression were detected by CCK-8 assay, glucose uptake assay and Western blot.

RESULTS

MicroRNA-218 expression level was decreased while GLUT1 expression level was increased in tumor tissues compared with adjacent healthy tissues. Serum level of microRNA-218 was lower, while serum level of GLUT1 was higher in cancer patients than that in healthy control. Serum microRNA-218 and GLUT1 can be used to accurately predict OSCC and its prognosis. MicroRNA-218 knockdown promoted tumor cell proliferation, increased glucose uptake and promoted GLUT1 expression.

CONCLUSIONS

Inhibition of microRNA-218 can promote oral cancer cell growth by targeting GLUT1 to affect glucose metabolism.

Safety and efficacy of taurine as an add-on treatment for tics in youngsters

BACKGROUND AND PURPOSE

The pathophysiological model of tics generally describes disruption of γ-aminobutyric acid transmission, and taurine is found to be an agonist of γ-aminobutyric acid receptors. The study aimed to evaluate the safety and efficacy of taurine as an add-on treatment for tics.

METHODS

Four hundred and four youngsters with tic disorders were randomly assigned to 12 weeks of either oral taurine or placebo. The Yale Global Tic Severity Scale was used to measure tic severity. The primary outcome measure was global severity scores reduced by more than 60% compared with baseline scores.

RESULTS

Three hundred and eighty-two patients were successfully treated. At week 4, no significant differences were found in the treatment effect and the total occurrence of adverse drug reactions between the taurine and placebo groups. At week 12, the proportion of significant improvement in tics was significantly higher in the taurine group than the placebo group (53.4% with taurine versus 34.5% without taurine; relative risk 1.546; P < 0.001), and no group differences were found in the total occurrence of adverse drug reactions.

CONCLUSIONS

Taurine is safe and effective for tics.

Oral vaccination with the porcine circovirus type 2 (PCV-2) capsid protein expressed by Lactococcus lactis induces a specific immune response against PCV-2 in mice

AIMS

Porcine circovirus type 2 (PCV2) can cause postweaning, multisystemic wasting syndrome in pigs, which leads to enormous losses in the swine industry worldwide. Here, a genetically engineered Lactococcus strain expressing the main protective antigen of PCV2, the Cap protein, was developed to act against PCV2 infection as an oral vaccine.

METHODS AND RESULTS

Expression of the Cap protein was confirmed via western blot, ELISA and fluorescence microscopy. Over 90% of the recombinant pAMJ399-Cap/MG1363 survived a simulated gastrointestinal transit. It also survived the murine intestinal tract for at least 11 days. Then, the safety and immunogenicity of pAMJ399-Cap/MG1363 in orally immunized mice was evaluated. The levels of the sIgA, IgG and cytokines (IL-4 and IFN-γ) obtained from the mice immunized with pAMJ399-Cap/MG1363 were significantly higher than those in the control groups.

CONCLUSIONS

pAMJ399-Cap/MG1363 can survive in the gastrointestinal transit and effectively induce mucosal, cellular and humoral immune response against PCV2 infection via oral administration.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study demonstrates the potential of the genetically engineered Lactococcus lactis as a candidate for an oral vaccine against PCV2.

[Molecular characterization of Cryptosporidium species in sheep and goats in Anhui Province and neighboring provinces]

OBJECTIVE

To investigate the prevalence and molecular features of Cryptosporidium in sheep and goats from Anhui Province and neighboring provinces.

METHODS

A total 832 and 781 fresh fecal samples were collected from seven large-scale sheep farms and ten large-scale goat farms in Anhui Province and neighboring provinces of Henan, Jiangsu and Shandong. The prevalence and species of Cryptosporidium were investigated in the fecal samples from the sheep and goats in the study areas using nested PCR assay based on the Cryptosporidium-specific SSU rDNA gene, and the subgenotypes of C. parvum and C. ubiquitum were characterized by amplification and sequencing of the 60 kDa glycoprotein (gp60) gene.

RESULTS

The overall prevalence of Cryptosporidium was 5.8% (48/832) in sheep and 8.7% (68/781) in goats in Anhui Province and neighboring provinces, respectively. The SSU rDNA gene-based PCR assay identified C. xiaoi and C. ubiquitum in sheep and C. parvum in goats, and subtyping revealed that all C. ubiquitum subgenotypes belonged to XIIa subtype 2 and C. parvum subgenotypes belonged to IIdA19G1.

CONCLUSIONS

The identification of zoonotic C. ubiquitum XIIa subtype 2 and C. parvum subtype IIdA19G1 suggests that sheep and goats may serve as a potential source for human Cryptosporidium infections.

Space-Confined Synthesis of Core-Shell BaTiO3@Carbon Microspheres as a High-Performance Binary Dielectric System for Microwave Absorption

Binary dielectric composites are viewed as a kind of promising candidate for conventional magnetic materials in the field of microwave absorption. Herein, we demonstrate the successful fabrication of core-shell BaTiO₃@carbon microspheres through a space-confined strategy. The electromagnetic properties of BaTiO₃@carbon microspheres can be easily tailored by manipulating the relative content of carbon shells. It is confirmed that dielectric loss of these composites mainly benefits from conductivity loss, dipole orientation polarization, and interfacial polarization, and the core-shell configuration shows its positive contribution to the reinforcement of interfacial polarization. When the content of carbon shells is optimized, the as-obtained composite will display excellent microwave-absorption performance due to decent attenuation and well-matched impedance. The strongest reflection loss can reach up to -88.5 dB at 6.9 GHz with the absorber thickness of 3.0 mm, and the qualified bandwidth below -10.0 dB covers 9.0-12.0 GHz, when the thickness is designated at 2.0 mm. Such a performance in the X band is superior to those of most typical binary dielectric systems. More importantly, these BaTiO₃@carbon microspheres maintain good performance after being treated under high-temperature and acidic conditions for a long time, manifesting their promising prospect for practical application. It is believed that these results may be helpful for the development of multicomponent dielectric systems as high-performance microwave absorbing materials.

Light Trapping in Conformal Graphene/Silicon Nanoholes for High-Performance Photodetectors

Hybrid graphene/silicon heterojunctions have been widely utilized in photodetectors because of their unique characteristics of high sensitivity, fast response, and CMOS compatibility. However, the photoresponse is restricted by the high reflectance of planar silicon (up to 50%). Herein, an improved graphene/Si detector with excellent light absorption performance is proposed and demonstrated by directly growing graphene on the surface of silicon nanoholes (SiNHs). It is shown that the combination of SiNHs with conformal graphene provides superior interfaces for efficient light trapping and transport of the photoexcited carriers. A high absorption of up to 90% was achieved, and the conformal graphene/SiNH-based photodetectors exhibited a higher photoresponsivity (2720 A/W) and faster response (∼6.2 μs), compared with the counterpart of the planar graphene/Si, for which the corresponding values are 850 A/W and 51.3 μs. These results showcase the vital role of the material morphology in optoelectronic conversion and pave the way to explore novel high-performance heterojunction photodetectors.

High efficiency active wavefront manipulation of spin photonics based on a graphene metasurface

Metasurfaces have been widely studied for manipulating light fields. In this work, a novel metasurface element is achieved with a high circular polarization amplitude conversion efficiency of 88.5% that creates an opposite phase shift ranging from -180° to 180° between incidence and reflection for different spin components. By arranging the elements according to different requirements, spin-dependent reflection, focusing and scattering are demonstrated. It is also demonstrated that tuning of the Fermi energy is an viable way to active control the circular polarization conversion efficiency and expand the applicable bandwidth. The results open a new route for modifying and designing the wavefront of circular polarized light.

[Progress on estimation and projection of HIV epidemics]

Due to the continuous improvement on HIV surveillance system and the diversity of data sources, various methodologies on estimation and projection of HIV/AIDS present greater contribution in exploring the natural history and related burden of HIV in the future. Different kinds of methods have been developed by professionals, both at home and abroad. This paper reviews the rationale, requirement, application, strength and limitation of the related methodologies that have been widely used in this field, to provide reference and evidence for the application and selection of related methodologies in the future.