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Very recently, half-hydrogenated germanene has been achieved in an experiment. In this paper, we investigate the effects of tetracyanoquinodimethane (TCNQ) molecular adsorption and strain on the electronic properties of half-hydrogenated germanene through first-principles. As an electron-acceptor molecule, TCNQ is exploited to non-covalently functionalize the half-hydrogenated germanene. However, this physical adsorption induces a ferromagnetic semiconductor–metal transition in half-hydrogenated germanene due to charge transfer from the substrate to the TCNQ molecule. More importantly, the superstructure of half-hydrogenated germanene/TCNQ is extremely sensitive to biaxial tensile strain. Under the biaxial tensile strain of 0.25%, the ferromagnetic semiconductor–metal transition induced by molecular adsorption can surprisingly be overturned. Meanwhile, a strong p-type doping is exhibited. Remarkably, it would return from a ferromagnetic semiconductor to a metal again when the biaxial tensile strain increases to 1.5%. Our analysis based on the structural and electronic properties of half-hydrogenated germanene/TCNQ indicates that such metal–semiconductor–metal transition in half-hydrogenated germanene/TCNQ under biaxial tensile strain may originate from the strong local deformation, resulting in the energy of the valence band maximum decreasing below or increasing above the Fermi level. [ABSTRACT FROM AUTHOR]

Fully-hydrogenated germanene, named germanane, represents a new nanostructured material for a variety of potential applications, such as electronics and optoelectronics. However, a critical requirement for developing practical and reliable electronic devices based on germanane consists of achieving a flexibly controllable charge carrier and doping level. Different to the conventional doping methods such as ion implantation and diffusion, by first-principles calculations we demonstrate that tetracyanobenzene (TCNB) molecular adsorption could introduce effective p-type doping in germanane due to the combination of germanane with electroactive acceptor molecule TCNB. The corresponding energy difference between the empty band minimum of the dopant and the valence band maximum for electron excitation is 0.173 eV. More importantly, this nondestructive p-type doping could be linearly tuned under an external E-field. Analysis of charge transfer by means of the equivalent capacitor model and the shift of energy levels in the superstructure of germanane/TCNB further reveals that the superposition of the external E-field and molecular adsorption-induced internal E-field plays a key role in the charge transfer between TCNB and germanane, especially in achieving a controllable p-type molecular doping level in germanane. Such convenient and flexible E-field-engineering of p-type molecular doping in germanane would be very helpful for potential applications of germanane-based electronic and optoelectronic devices in the future. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Long noncoding RNAs (lncRNAs) have been reported to be vital in tumor progression. Hepatocellular carcinoma (HCC) is a common type of fatal primary liver cancers worldwide. This study aims to determine whether lncRNA SNHG7 (small nucleolar RNA host gene 7) functions in the metastasis of HCC. PATIENTS AND METHODS: Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was conducted to detect the SNHG7 expression in HCC cells and tissue samples. Moreover, function assays were performed in vitro to identify the role of SNHG7 in metastasis of HCC cells. Western blot assay was used to explore the possible mechanism. RESULTS: SNHG7 expression was remarkably higher in HCC tissues than that in adjacent tissues. Moreover, HCC migration and invasion were suppressed after silence of SNHG7 in HCC cells. Moreover, after silence of SNHG7, RBM5 was upregulated in HCC cells. Besides, the expression of RBM5 in tumor tissues was negatively correlated to the expression of SNHG7. CONCLUSIONS: Our study suggests that SNHG7 could promote cell invasion and migration in HCC cells through downregulating RBM5, which may offer a new therapeutic intervention for HCC patients. [ABSTRACT FROM AUTHOR]

The site preference of Re in NiAl was studied using first-principles calculations. The calculation of formation energies of the NiAl alloys indicated the site preference of Re on the Ni sites. The valence band structures of the NiAl alloys were investigated by photoelectron spectroscopy. The valence band spectra of the NiAl with Re shifted away from the Fermi energy level so that the Ni d-band centroid moved to a higher energy by 0.25 eV as Re was added. Such a shift could be attributed to the Ni-Re interaction, which was supported by the photoelectron spectroscopy measurement. [ABSTRACT FROM AUTHOR]

A correction is presented to the article "Long noncoding RNA SNHG7 represses the expression of RBM5 to strengthen metastasis of hepatocellular carcinoma" which appeared in the 2020 issue.

Germanane, fully hydrogenated germanene, has recently attracted great interest, both theoretical and experimental. In this paper we thoroughly study strain-tunable n/p-type doping in germanane by adsorption of tetrathiafulvalene (TTF)/tetracyanoquinodimethane (TCNQ) molecules through first-principles calculations. The results show that both TTF and TCNQ molecules can non-covalently functionalize the electronic properties of germanane. Not surprisingly, TTF molecular adsorption induces n-type doping in germanane because the TTF molecule is a typical electron donor. Moreover, a linearly tunable band gap of germanane and differing n-type doping strengths can be realized by a biaxial strain ranging from -3% to 3%. Analysis indicates that tensile strain would promote the doping effect whereas compressive strain would inhibit it. Comparatively, TCNQ molecular adsorption induces a germanane/TCNQ system which exhibits metallic characteristics. Surprisingly, however, under a tensile strain of 2.5%, a strong p-type doping effect is achieved in germanene/TCNQ. In particular, with increasing tensile strain over the range 2.5%-3%, the strain-tunable p-type doping effect decreases gradually. Such a multiple effect of molecular adsorption and strain on the electronic properties of germanane could be helpful for potential future applications of germanane-based electron devices.

Liver regeneration after partial hepatectomy (PH) is a complex and well-elaborated biological process whereby synchronized cell proliferation is induced in response to the loss of liver mass. Insulin-like growth factor 1 (IGF1) signaling, which plays a crucial role in normal growth and development, is involved in the process of liver regeneration. To assess the changes in the levels of serum IGF1 and hepatic IGF1 receptor (IGF1R), we established a mouse model for PH. This also allowed us to further explore the mechanisms that participate in the regulation of liver regeneration. Serum IGF1 dramatically decreased immediately after PH, and was mildly elevated afterwards. This was also confirmed in patients who had undergone PH. Immunohistochemistry and Western blotting showed that hepatic IGF1R expression was elevated after surgery in mice. Hepatosomatic index showed a mild elevation 1 week after surgery and a marked elevation after 3 weeks. Western blotting showed increased levels of forkhead box O3 (FOXO3), but the phosphorylated forms of v-akt murine thymoma viral oncogene homolog 1 (AKT1), glycogen synthase kinase 3 beta (GSK3B) and FOXO3 were all downregulated. Our data show that the GSK3B-FOXO3 pathway is activated after PH, and this may be one of the mechanisms that lead to upregulation of hepatic IGF1R after PH. All these changes after surgery promote liver regeneration.

Objective: To describe diseases that may present with the reversed halo sign (RHS) on high-resolution CT, and therefore to improve the recognition of this thoracic radiological feature. Methods: We retrospectively reviewed the HRCT scans and medical records of 5 patients who presented with RHS on chest CT from Peking University Third Hospital. With "reversed halo sign, fairy ring, atoll sign" as the Chinese and English keywords, 420 cases from the literatures were also reviewed through PubMed, Wanfang and CNKI databases until August 2015. Results: The 5 patients were all males, aging 19-55 years. The diagnosis of the diseases included cryptogenic organizing pneumonia (patient 1), pulmonary tuberculosis (patient 2), pulmonary infarction (patient 3), pulmonary edema (patient 4) and mycoplasma pneumonia (patient 5). Literature review showed that RHS was observed in 206 cases of infectious pulmonary diseases and 219 cases of noninfectious pulmonary diseases. Invasive fungal infection (including 59 cases of mucormycosis and 27 aspergillosis) and pulmonary tuberculosis (79 cases) predominated in infectious pulmonary diseases. However, in non-infectious pulmonary diseases, RHS was most frequently observed in organizing pneumonia (66%), sarcoidosis, lung cancer, pulmonary infarction, pulmonary edema and other interstitial lung diseases. There were some differences in the morphologic findings of RHS among invasive fungal infection, pulmonary tuberculosis and organizing pneumonia. In addition, our patient with mycoplasma pneumonia was the first case reported to present with RHS on HRCT. Conclusions: Although a wide spectrum of pulmonary diseases may present with RHS on chest CT, this sign is still a characteristic thoracic radiological feature, which is more commonly found in organizing pneumonia, pulmonary tuberculosis and invasive fungal infection, and is helpful in differential diagnosis.

The carcass characteristics of 334 Chinese Yellow Cattle, and their Simmental and Limousin crosses, were investigated in abattoirs in Hebei and Sandong provinces of China. The overall slaughter age was 4.8±2.2 years at a mean liveweight of 527.28±77.0 kg. Mean ages and liveweights for Yellow Cattle and its crosses were, respectively, 5.29±2.03 and 2.85±1.71 years and 519.43±78.7 and 563.13±56.8 kg. Carcass weights varied considerably and, consequently, so did subcutaneous fat depths and dressing percentages. Overall, mean carcass weights, subcutaneous fat depths and, dressing percentages and eyemuscle areas were 283.9±64.1 kg, 14.0±8.0 mm, 54.0±4.0%, and 62.7 ±13.3 cm(2), respectively. Compared with pure Yellow Cattle, the crosses were slaughtered at younger age, and had larger live and carcass weights, higher dressing percentages, less subcutaneous fat depth and bigger eyemuscle areas. It is concluded that crossbreeding can significantly improve Yellow Cattle' meat productivity, however feeding systems need to be improved and an appropriate grading system developed to improve beef production and quality in China.

Fifty gram oral glucose challenge test (50g GCT) was performed, as a screening test of diabetes mellitus (DM), in 289 pregnant women, and further, a 75g oral glucose tolerance test (OGTT) was done in those women with glucose level > 7.78 mmol/L. The results showed that 49 women had a glucose level > 7.78 mmol/L (16.96%), among whom 15 (5.19%) were identified as having gestational impaired glucose tolerance (GIGT), and 5 (1.73%) had gestational diabetes mellitus (GDM) as diagnosed by 75g OGTT. The prevalence of PIH, premature rupture of membrane, fetal macrosomia, cesarean section, perinatal morbidity were higher in GIGT and GDM mothers and there was a positive correlation between glucose level of 50g GCT and the birth weight of newborns. It suggested that 50g GCT may be a preferable screening test for GDM since it is simple and cheap with high sensitivity and specificity.

Forty patients (25 cases of prostatic cancer and 15 cases of benign prostatic hyperplasia) were examined with radioimmunodetection (RAID) using antibody against r-Seminoprotein (r-Sm). The images of malignant tumor sites were revealed from the scan of single photon emission computerized tomography with the tracing of dual radionuclide and computer digital subtraction technique. Of the 25 patients with prostatic cancer tested, twenty-four were demonstrated in RAID with a positive rate of 96%. The ratio of taking in nuclide radioactivity between the tumor tissue and normal tissue (T/N) was 6.9 and the best showing time was the 96th hr from injection of radioactive antibody against r-Sm. The minimum diameter of the tumor detected in RAID was 0.5 cm. All of the 8 cases of metastatic prostatic cancer in pelvic or bone location were detected, with a rate of 100%. Of the 15 cases of benign prostatic hyperplasia, only one showed mild positive result. B-ultrasonography and CT showed a positive detective rate of 72.7% and 65%, respectively. Our results have indicated that RAID using 131I-labeled antibody against r-Sm possesses more advantages in specificity, because RAID not only defines the involved sites, but also shows the sites of the original tumors, and the metastatic location as well as the relationship between them.