Recent progresses on ion beam irradiation induced structure and performance modulation of two-dimensional materials.

Two-dimensional (2D) materials are receiving significant attention for both fundamental research and industrial applications due to their unparalleled properties and wide application potential. In this case, the controllable modulation of their structures and properties is essential for the realization and further expansion of their applications. Accordingly, ion beam irradiation techniques, with large scope to adjust parameters, high manufacturing resolution, and a series of advanced equipment being developed, have been demonstrated to have obvious advantages in manipulating the structure and performance of 2D materials. In recent years, many research efforts have been devoted to uncovering the underlying mechanism and control rules regarding ion irradiation induced phenomena in 2D materials, aiming at fulfilling their application potential as soon as possible. Herein, we review the research progress in the interaction between energetic ions and 2D materials based on the energy transfer model, type of ion source, structural modulation, performance modification of 2D materials, and then their application status, aiming to provide useful information for researchers in this field and stimulating more research advances.

Recent Research Progress in the Structure, Fabrication, and Application of MXene-Based Heterostructures.

Two-dimensional (2D) materials have received increasing attention in the scientific research community owing to their unique structure, which has endowed them with unparalleled properties and significant application potential. However, the expansion of the applications of an individual 2D material is often limited by some inherent drawbacks. Therefore, many researchers are now turning their attention to combine different 2D materials, making the so-called 2D heterostructures. Heterostructures can integrate the merits of each component and achieve a complementary performance far beyond a single part. MXene, as an emerging family of 2D nanomaterials, exhibits excellent electrochemical, electronic, optical, and mechanical properties. MXene-based heterostructures have already been demonstrated in applications such as supercapacitors, sensors, batteries, and photocatalysts. Nowadays, increasing research attention is attracted onto MXene-based heterostructures, while there is less effort spent to summarize the current research status. In this paper, the recent research progress of MXene-based heterostructures is reviewed, focusing on the structure, common preparation methods, and applications in supercapacitors, sensors, batteries, and photocatalysts. The main challenges and future prospects of MXene-based heterostructures are also discussed to provide valuable information for the researchers involved in the field.

Recent Advances on Tuning the Interlayer Coupling and Properties in van der Waals Heterostructures.

2D van der Waals (vdW) heterostructures are receiving increasing research attention due to the theoretically amazing properties and unprecedented application potential. However, the as-synthesized heterostructures are generally underperforming due to the weak interlayer coupling, which inspires the researchers to find ways to modulate the interlayer coupling and properties, realizing the tailored performance for actual applications. There have been a lot of publications regarding the controllable regulation of the structures and properties of 2D vdW heterostructures in the past few years, while a review work summarizing the current advances is not yet available, though it is significant. This paper conducts a state-of-the-art review regarding the current research progress of performance modulation of vdW heterostructures by different techniques. First, the general synthesis methods of vdW heterostructures are summarized. Then, different performance modulation techniques, that is, mechanical-based, external fields-assisted, and particle beam irradiation-based methods, are discussed and compared in detail. Some of the newly proposed concepts are described. Thereafter, applications of vdW heterostructures with tailored properties are reviewed for the application prospects of the topic around this area. Moreover, the future research challenges and prospects are discussed, aiming at triggering more research interest and device applications around this topic.

Fabrication of Nanopore in MoS2-Graphene vdW Heterostructure by Ion Beam Irradiation and the Mechanical Performance.

Nanopore structure presents great application potential especially in the area of biosensing. The two-dimensional (2D) vdW heterostructure nanopore shows unique features, while research around its fabrication is very limited. This paper proposes for the first time the use of ion beam irradiation for creating nanopore structure in 2D vdW graphene-MoS2 heterostructures. The formation process of the heterostructure nanopore is discussed first. Then, the influence of ion irradiation parameters (ion energy and ion dose) is illustrated, based on which the optimal irradiation parameters are derived. In particular, the effect of stacking order of the heterostructure 2D layers on the induced phenomena and optimal parameters are taken into consideration. Finally, uniaxial tensile tests are conducted by taking the effect of irradiation parameters, nanopore size and stacking order into account to demonstrate the mechanical performance of the heterostructure for use under a loading condition. The results would be meaningful for expanding the applications of heterostructure nanopore structure, and can arouse more research interest in this area.

Solid-Pseudopapillary Neoplasm of the Pancreas: A 63-Case Analysis of Clinicopathologic and Immunohistochemical Features and Risk Factors of Malignancy.

PURPOSE: Solid-pseudopapillary neoplasm (SPN) of the pancreas, a rare tumor, has low malignant potential. However, some patients develop metastasis and recurrence after resection, with aggressive biological behaviors. This study aimed to explore the features and risk factors associated with the aggressive biological behaviors of SPNs. PATIENTS AND METHODS: We retrospectively analyzed the clinicopathological and long-term follow-up data of 63 patients diagnosed with SPN at the First Affiliated Hospital of Bengbu Medical College between January 2007 and February 2019. RESULTS: Sixty-three patients presented atypical clinical symptoms. The median tumor size was 7.0 cm (range, 2.4-17 cm), and imaging features were solid and cystic or solid tumors with uneven density. Frequent and diffuse nuclear LEF1 protein expression (94.2%) was observed with LEF1 having a higher sensitivity and specificity. Overall survival significantly correlated with tumor size, Ki-67 index, and lymph node metastasis (P < 0.05). CONCLUSION: SPN is a rare low-grade malignancy with a specific pseudopapillary structure. LEF1 is an effective biomarker of SPNs. Although SPNs generally display indolent biological behavior, a large tumor size, high proliferation index, and lymph node metastasis may be risk factors for the aggressive behavior and poor prognosis of SPN.

Clinicopathological features and prognostic factors associated with gastroenteropancreatic mixed neuroendocrine non-neuroendocrine neoplasms in Chinese patients.

BACKGROUND: The incidence of mixed neuroendocrine-non-neuroendocrine neoplasms (MiNEN) is low. To improve our understanding of this rare tumor type and optimally guide clinical treatment, associated risk factors, clinical manifestations, and prognosis must be explored. AIM: To identify risk factors that influence the prognosis of patients with gastroenteropancreatic MiNEN (GEP-MiNEN). METHODS: We retrospectively analyzed the clinical data of 46 patients who were diagnosed with GEP-MiNEN at the First Affiliated Hospital of Bengbu Medical College (Anhui, China) between January 2013 and December 2017. Risk factors influencing the prognosis of the patients were assessed using Kaplan-Meier curves and cox regression models. We compared the results with 55 randomly selected patients with gastroenteropancreatic GEP neuroendocrine tumors, 47 with neuroendocrine carcinomas (NEC), and 58 with poorly differentiated adenocarcinoma. RESULTS: Among the 46 patients with GEP-MiNEN, thirty-five had gastric tumors, nine had intestinal tumors (four in the small intestine and five in the colon and rectum), and two had pancreatic tumors. The median age of the patients was 66 (41-84) years, and the male-to-female ratio was 2.83. Thirty-three (71.7%) patients had clinical stage III and IV cancers. Distant metastasis occurred in 14 patients, of which 13 had metastasis to the liver. The follow-up period was 11-72 mo, and the median overall survival was 30 mo. Ki-67 index ≥ 50%, high proportion of NEC, lymph node involvement, distant metastasis, and higher clinical stage were independent risk factors affecting the prognosis of patients with GEP-MiNEN. The median overall survival was shorter for patients with NEC than for those with MiNEN (14 mo vs 30 mo, P = 0.001), but did not significantly differ from those with poorly differentiated adenocarcinoma and MiNEN (30 mo vs 18 mo, P = 0.453). CONCLUSION: A poor prognosis is associated with rare, aggressive GEP-MiNEN. Ki-67 index, tumor composition, lymph node involvement, distant metastasis, and clinical stage are important factors for patient prognosis.

Sinonasalteratocarcinosarcoma: a report of two cases and clinicopathological analysis.

Sinonasalteratocarcinosarcoma (SNTCS) is a highly malignant and aggressive neoplasm which can quickly damage the local soft tissue, bone tissue, and invade orbital and intracranial tissues. It also can result in local lymph node and distant organ metastasis. The data from 2 cases of SNTCS from the First Affiliated Hospital of Bengbu Medical College (China), treated with radiotherapy and chemotherapy followed by cranio-facial resection, were analyzed since 2016. The main symptoms of the two patients were of the nasal cavity with nasal congestion and runny nose. There was no recurrence after surgery. Microscopic examination showed that the composition of tumor tissue was very complex, as different degrees of differentiation of the origin of the organization could be seen in the tumor tissue. It was mixed with teratoma and cancer sarcoma components and undifferentiated/primitive tumor cells could also be seen in local tumor stroma. SNTCS is a very rare complex tissue composition of malignant tumors, because of its complex pathological morphology and high possibility of misdiagnosis. Pathological features and immunohistochemical markers can contribute to the diagnosis and differential diagnosis of the disease.

COL1A1-PDGFB gene fusion in dermatofibrosarcoma protuberans: a useful diagnostic tool and clinicopathological analysis.

The PDGFB gene is found at 22q12.3-q13.1, and the COL1A1 gene is located at 17q21.3-q22.1. If the COL1A1 gene of 17q21-22 is fused with the PDGFB gene of 22q13.1, then it forms a new COL1A1-PDGFB fusion gene, one that has been found in dermatofibrosarcoma protuberans (DFSP) and lasts for many years. The expression of PDGFB loses the regulation of upstream inhibitory factors and leads to the mass production of COL1A1-PDGFB chimeric mRNA under the initiation of COL1A1 sequence, a crucial factor in the development of DFSP. In our study, we retrospectively analyzed 2 cases: case 1 is a 25-year-old student with three surgical resections in his right lumbar region. Initially, his diagnosis (from another hospital in 2009) was vascular lymphangioma. When the disease recurred after 6 years, he went to our hospital and the diagnosis was giant cell fibroblastoma (GCF). Molecular pathology (using the fluorescence in situ hybridization, FISH) showed the COL1A1-PDGFB gene fusion, presented as the fusion of 3 or more red and green signals. In 2017, the patient had another recurrence of the disease, and he underwent a third surgical resection. The other case is a 51-year-old woman who had presented with pain in her left lumbosacral, accompanied by left buttock and left thigh numbness for 3 months. The diagnosis was DFSP, which also showed COL1A1-PDGFB gene fusion. Here we review the clinicopathologic features and differential diagnosis of this rare tumor, so that it can be better recognized.