[Emission Characteristics of Organic Carbon and Elemental Carbon in PM10 and PM2.5 from Vehicle Exhaust and Civil Combustion Fuels].

To study the emission characteristics of carbonaceous aerosol in particulate matter emitted from vehicle exhaust and main civil combustion fuels, organic carbon (OC) and elemental carbon (EC) in PM10 and PM2.5 samples from vehicle sources (gasoline vehicles, light duty diesel vehicles, and heavy duty diesel vehicles), civil coal (chunk coal and briquette coal), and biomass fuels (wheat straw, wood plank, and grape branches) were collected and analyzed by using a multifunctional portable dilution channel sampler and the Model 5L-NDIR OC/EC analyzer. The results showed that there were significant differences in the proportion of carbonaceous aerosols in PM10 and PM2.5from different emission sources. The proportions of total carbon (TC) in PM10 and PM2.5 of different emission sources were 40.8%-68.5% and 30.5%-70.9%, respectively, and the OC/EC were 1.49-31.56 and 1.90-87.57, respectively. The carbon components produced by different emission sources were dominated by OC, and the OC/TC values in PM10 and PM2.5 were 56.3%-97.0% and 65.0%-98.7%, respectively. The proportions of OC in carbonaceous aerosols in PM10and PM2.5 were in the descending order of:briquette coal>chunk coal>gasoline vehicle>wood plank>wheat straw>light duty diesel vehicle>heavy duty diesel vehicle and briquette coal>gasoline car>grape branches>chunk coal>light duty diesel vehicle>heavy duty diesel vehicle, respectively. The main components of carbonaceous aerosols in PM10 and PM2.5 emitted from the various emission sources were different, and source apportionment of carbonaceous aerosols could be accurately distinguished by their ingredient composition profiles.

[Current understanding of intervertebral space height in anterior cervical fusion].

Anterior cervical fusion surgery is the first choice for spine surgeons in the treatment of cervical spine diseases. It has significant effects in treating cervical degenerative diseases, trauma and tumors and other cervical diseases. In anterior cervical fusion, it is necessary to use a distractor to properly distract the intervertebral space, so as to fully expose and relieve the compressive factors, restore the physiological height, curvature and stability of the lesion segment, and achieve the best surgical effect. However, there is currently no consensus on the standard distraction height for the intervertebral space during anterior cervical surgery. This article reviewsed the progress of intervertebral space height in anterior cervical fusion from three dimensions:the relationship between intervertebral space height and cervical disc degeneration mechanism, the selection of intervertebral space height during operation, the recovery of intervertebral space height and the postoperative effect, so as to provide theoretical basis and reference for spinal surgeons when performing intervertebral distraction during operation.

New insights in diagnosis and treatment of gastroenteropancreatic neuroendocrine neoplasms.

Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) are rare epithelial neoplasms derived from pluripotent endocrine cells along the gastrointestinal tract and pancreas. GEP-NENs are classified into well-differentiated neuroendocrine tumors and poorly differentiated neuroendocrine carcinomas. Despite overlapping morphological features, GEP-NENs vary in molecular biology, epigenetic, clinical behavior, treatment response, and prognosis features and remain an unmet clinical challenge. In this review, we introduce recent updates on the histopathologic classification, including the tumor grading and staging system, molecular genetics, and systemic evaluation of the diagnosis and treatment of GEP-NENs at different anatomic sites, together with some insights into the diagnosis of challenging and unusual cases. We also discuss the application of novel therapeutic approaches for GEP-NENs, including peptide receptor radionuclide therapy, targeted therapy, and immunotherapy with immune checkpoint inhibitors. These findings will help improve patient care with precise diagnosis and individualized treatment of patients with GEP-NENs.

Distinct Prognosis of High Versus Mid/Low Rectal Cancer: a Propensity Score-Matched Cohort Study.

BACKGROUND: Rectal cancers have long been treated as a single-entity disease; however, whether the prognosis of high rectal cancer (inferior margin located 10.1 to 15.0 cm from the anal verge) differs from that of mid/low rectal cancer (0 to 10.0 cm) remains disputed. METHODS: Patients with stages I-III rectal adenocarcinomas undergoing curative-intent surgery were enrolled between 2007 and 2013 in this retrospective analysis. Exclusion criteria were neoadjuvant therapy or concurrent cancers. Propensity score matching and Cox regression analysis were performed to compare a 5-year overall and cancer-specific survival between patients with high and mid/low rectal cancer. RESULTS: Of 613 patients who met the inclusion criteria, 199 (32.5%) and 414 (67.5%) had high and mid/low rectal cancer, respectively. After propensity score matching (187 cases for each group), the high group showed a better overall survival (70.9 vs. 56.9%, p = 0.042) and cancer-specific survival (77.4 vs. 60.3%, p = 0.028) at 5 years compared with the mid/low group with stage III disease. However, high rectal cancer did not demonstrate prognostic superiority in stages I-II disease. Multivariate analysis identified high tumor location as an independent prognostic factor for cancer-specific survival (hazards ratio = 0.422, 95% confidence interval 0.226-0.786, p = 0.007) and overall survival (hazards ratio = 0.613, 95% confidence interval 0.379-0.991, p = 0.046). CONCLUSIONS: Patients with stage III high rectal adenocarcinoma demonstrated better overall and cancer-specific survival than those with mid/low type, and tumor location was an independent prognostic factor for patients with rectal carcinomas.

[Spatial interpolation model of soil organic carbon density considering land-use and spatial heterogeneity.] / 综合土地利用及空间异质性的土壤有机碳空间插值模型.

Soil organic carbon pool is an important component of terrestrial carbon pool. Soil organic carbon pool and its dynamic change have important influence on carbon cycle in terrestrial ecosystem. Soil organic carbon density (SOCD) is an important parameter of soil carbon storage, and it is also an important index to evaluate farmland soil quality. Accurate prediction of regional organic carbon density spatial distribution is of great significance to the development of precision agriculture. A total of 242 farmland soil samples collected from the Jianghan Plain were used to explore the effects of land use types on the spatial distribution of SOCD in plain areas. Moreover, in the presence of spatial heterogeneity and spatial outliers of SOCD, three Kriging approaches combining land use types were used for the spatial prediction of SOCD. They were dummy variable regression Kriging (DV_RK), mean centering ordinary Kriging (MC_OK1) and median centering ordinary Kriging (MC_OK2). Results showed that the difference of land use types between paddy field and irrigable land was one of the reasons for the spatial heterogeneity of SOCD in the study area, resulting in spatial non-stationary characteristics of SOCD and lowering the performance of OK. DV_RK, MC_OK1 and MC_OK2, however, eliminating the impacts of SOCD spatialheterogeneity caused by land use types while modeling, enhancing the model stability. Therefore, the prediction accuracy of these three models was higher than that of ordinary Kriging (OK). Moreover, MC_OK2 outperformed the others in terms of model reliability, prediction accuracy and the ability to explain the total variance of SOCD. In summary, as an easily accessed auxiliary variable, land use type could effectively decrease the effects of spatial heterogeneity and spatial outliers on SOCD spatial interpolation model, improving the prediction performance and reducing the model uncertainty. SOCD map with higher quality could also be achieved to help reveal the spatial characteristics of SOCD for guiding the agricultural production.

Evolution of Slow Magnetic Relaxation: from Diamagnetic Matrix Y(OH)CO3 to Dy(0.06)Y(0.94)(OH)CO3 with High Spin-Reversal Barrier and Blocking Temperature.

A stable Dy(III)-dispersed compound with single-molecule magnet behavior, Dy(0.06)Y(0.94)(OH)CO3, was isolated by a general strategy targeted at the doping of paramagnetic Dy(3+) into a diamagnetic 3D inorganic network of Y(OH)CO3. The single-ion origin of slow magnetic relaxation was gradually released as variations of the dysprosium/yttrium ratio and finally gave a relatively large spin-reversal barrier around 200 K and high hysteresis temperature of 8 K. This study opens up new opportunities to investigate the slow magnetic relaxation and magnetostructural correlation by choosing a suitable inorganic architecture with strong axial anisotropy.

Single-Molecule-Magnet Behavior in a [2 × 2] Grid Dy(III)4 Cluster and a Dysprosium-Doped Y(III)4 Cluster.

Thanks to the MeCN hydrolysis in situ reaction, a [2 × 2] square grid Dy(III)4 cluster based on a polypyridyl triazolate ligand, [Dy4(OH)2(bpt)4(NO3)4(OAc)2] (1), was separated successfully and characterized through single-crystal X-ray diffraction and SQUID magnetometry. The frequency-dependent signals in the out-of-phase component of the susceptibility associated with slow relaxation of the magnetization confirmed that complex 1 displays single-molecule magnet (SMM) behavior. Two distinct slow magnetic relaxation processes, with effective energy barriers Ueff1 = 93 cm(-1) for fast relaxation and Ueff2 = 143 cm(-1) for slow relaxation observed under a zero direct-current field, are mainly attributed to the origin of single-ion behavior, which can be further acknowledged by the magnetic investigation of a dysprosium-doped yttrium cluster. Besides, it should be noted that complex 1 represents so far the highest energy barrier among the pure Dy(III)4 SMMs.