Monodispersed porous crystalline TiO(2), SrTiO(3), and BaTiO(3) spheres were produced through a one-step hydrothermal process from amorphous TiO(2) spheres. The resulting samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and nitrogen sorption measurements. On the basis of the characterization results, we proposed a formation process of these porous spheres according to a mechanism analogous to the Kirkendall effect. This study provides a general way to synthesize porous titania-based spheres.

Ablative hypofractionated radiotherapy (HFRT) significantly improves the overall survival of inoperable non-small cell lung cancer (NSCLC) patients compared with conventional radiation therapy. However, the radiobiological mechanisms of ablative HFRT remain largely unknown. The purpose of this study was to investigate the dynamic changes of tumor vessels and perfusion during and after ablative hypofractionated radiotherapy. Lewis lung carcinoma-bearing mice were treated with sham (control) and ablative hypofractionated radiotherapy of 12 Gy in 1 fraction (12 Gy/1F) and 36 Gy in 3 fractions (36 Gy/3F). Tumor microvessel density (MVD), morphology and function were examined at different times after irradiation. The results showed that, compared to the controls the MVD and hypoxia in ablative HFRT groups decreased, which were accompanied by an increase in the number of pericytes and their coverage of vessels. Functional tests revealed that tumor hypoxia and perfusion were improved, especially in the 36 Gy/3F group. Our results revealed that ablative hypofractionated radiotherapy not only repressed MVD and hypoxia, but also increased the vascular perfusion and the number of pericyte-covered vessels, suggesting that ablative HFRT normalized the tumor vasculature.

treatments: fluorination, [18] nonmetal, [19] or transition-metal atoms [20] adsorption, phase transition [21] and substitution doping with transition-metal (TM) atoms, [22,23] NM metal atoms [23,24] or nonmetal elements. [23,25] Intriguingly, Zhang et al. [26] found an obvious magnetic transition from NM to FM ordering in N-doped ReS 2 nanospheres experimentally. Subsequently, distorted monolayer ReS 2 with ferroelectric and ferromagnetic orders at above room temperature (RT) was synthesized by Zhang et al. [27] On the other hand, nonmagnetic TaS 2 , TaSe 2 , NbS 2 , NbSe 2 , and M 2 C (Hf, Nb, Sc, Ta, V) monolayers [6,9,28,29] could become ferromagnetic (FM) under biaxial tensile strain. In contrast, other theoretical studies had also shown that the magnetic moments of monolayer VS 2 and VSe 2 , [30,31] monolayer PtSe 2 with V Se , [32] and SnSe 2 armchair nanoribbons [33] could be enhanced rapidly with increasing biaxial tensile strain. However, it was very difficult to apply biaxial strain directly on 2D materials. Luckily, experimental methods, including piezoelectric stretching [34] and exploiting the thermal expansion mismatch, [35] had been performed, but these methods required additional sophisticated setups such as electromechanical device or focused laser beam. Thus, it is necessary to investigate alternative convenient ways to apply biaxial strain and explore its effect on the magnetic properties of ReS 2 .Here, we demonstrate the spontaneous formation of largescale web buckles from PAD-grown ReS 2 thin films. Raman spectroscopy and mapping confirm the grown-induced and buckled-induced strain of ReS 2 web buckles. Additionally, we examine the Raman peak position and intensity variations observed in ReS 2 web buckles and explore the magnetism to such strain variations. The temperature coefficients χ T of the films is estimated to be −(0.0087 ± 0.0008) cm −1 K −1 (flat zones) and −(0.0080 ± 0.0036) cm −1 K −1 (buckled zones) for the E g mode (at 152 cm −1 ) by temperature-dependent Raman spectra. More intriguingly, all the samples exhibit biaxial strain-mediated FM behaviors at RT, which is also confirmed by theoretical investigation. Our study suggests that strain engineering is an effective approach to mediate magnetic properties of 2D materials, thereby opening an alternative way for "straintronic" and spintronic applications.ReS 2 thin films (thickness ≈ 60 nm; Figure S1, Supporting Information) with a residual compressive strain can remain flat in ambient environment for days or months, and then could Buckling-driven delamination of thin films on rigid substrates is frequently observed, which leads to deterioration or failure of the film-based devices. However, it is observed for the first-time that web buckles could enhance room-temperature ferromagnetism in PAD-grown ReS 2 thin films. Here, room-temperature ferromagnetic ReS 2 thin films with web buckles are prepared by polymer-assisted deposition (PAD) for the first time. The morphology and crystalline structure of the samples are characterized ...

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Next‐generation sequencing provides an opportunity to detect viral species from RNA‐seq data of human tissues, but existing computational approaches do not perform optimally on clinical samples. We developed a bioinformatic method called VirTect for detecting viruses in neoplastic human tissues using RNA‐seq data. Here, we used VirTect to analyze RNA‐seq data from 363 head and neck squamous cell carcinoma (HNSCC) patients and identified 22 human papillomavirus (HPV)‐induced HNSCCs. These predictions were validated by manual review of pathology reports on histopathologic specimens. VirTect showed better performance in recall and accuracy compared to the two existing prediction methods, VirusFinder and VirusSeq, in identifying viral sequences from RNA‐seq data. The majority of HPV carcinogenesis studies thus far have been performed on cervical cancer and generalized to HNSCC. Our results suggest that carcinogenesis of HPV‐induced HNSCC and other cases of HNSCC involve different genes, so understanding the underlying molecular mechanisms will have a significant impact on therapeutic approaches and outcomes. In summary, RNA‐seq together with VirTect can be an effective solution for the detection of viruses from tumor samples and can facilitate the clinicopathologic characterization of various types of cancers with broad applications for oncology.

Positron emission tomography (PET) is widely used in the diagnosis of tumors, cardiovascular system diseases, and neurological diseases. Scintillation crystals are an important part of PET scanners; they can convert γ photons into fluorescent photons to obtain their energy, time, and position information. Currently, an important research goal in PET is to find scintillation crystals with better performance. In this work, the principle of scintillation crystals is introduced, and the properties and requirements of scintillation crystals in different PET scanners are analyzed. At present, Lu2(1−x)Y2xSiO5 (LYSO) is the scintillation crystal with the best comprehensive properties. LaBr3 performs even better regarding the timing characteristics and light output; however, LaBr3 has not been used in any PET scanner because of its deliquescence. Detectors made of Gd3(Ga, Al)5O12 (GAGG) exhibit a high depth of interaction (DOI) resolution and have considerable application potential. The application fields of PET are constantly expanding, and its future development aims to achieve high spatial resolution and high sensitivity, which require scintillation crystals with better performance.

This paper presents a unique preclinical positron emission tomography (PET) detector constructed with a monolithic scintillator ring (MSR) and two rings of silicon photomultipliers (SiPM). The inner diameter, outer diameter and length of the MSR were 48.5 mm, 58.5 mm, and 25.1 mm, respectively. The two SiPM rings, constructed with 46 SiPMs, were air-coupled to the two ends of the MSR detector. The center of gravity (COG) and artificial neural network (ANN) methods were adapted to decode the positions of the gamma interactions in the circumferential (θ) and axial (Z) directions, respectively. Collimating systems, consisting of a tungsten collimator and a highprecision displacement and rotating platform, were constructed to assess the decoding accuracies of the MSR detector in both θ and Z directions. The average intrinsic full-width half maximums (FWHMs) and mean absolute errors (MAEs) of the decoding accuracies were 0.94 mm and 0.33 mm in the circumferential direction, 2.45 mm and 1.08 mm in the axial direction. An energy resolution of 10.7% was measured at 511 keV. The scintillating photons generated by a pair of coincidence gamma photons overlap with each other, and cause circumferential parallax errors in the lines of response (LOR). The experimental results show that the average FWHM errors in the θ direction increased slightly from 0.94 mm to 1.14 mm when Δθ of the two single events was larger than 70°. The imaging performance of the MSR detector was also initially assessed with a Derenzo phantom filled with 18 F-FDG. The rods with a diameter larger than 1.2 mm can be resolved. The energy resolutions were 12.3% at 511 keV (single events), and 11.4% at 1022 keV (coincidence events). We concluded that it is feasible to construct the high-performance preclinical PET scanners using one or multiple MSR detectors.

Preclinical positron emission tomography (PET) is a sensitive and quantitative molecule imaging modality widely used in characterizing the biological processes and diseases in small animals. The purpose of this study is to investigate the methods to optimize a PET detector for high-resolution preclinical imaging. The PET detector proposed in this study consists of a 28 × 28 array of LYSO crystals 0.5 × 0.5 × 6.25 mm3 in size, a wedged lightguide, and a 6 × 6 array of SiPMs 3 × 3 mm2 in size. The simulation results showed that the most uniform flood map was achieved when the thickness of the lightguide was 2.35 mm. The quality of the flood map was significantly improved by suppressing the electronics noises using the simple threshold method with a best threshold. The peak-to-valley ratio of flood map improved 25.4% when the algorithm of ICS rejection was applied. An energy resolution (12.96% ± 1.03%) was measured on the prototype scanner constructed with 12 proposed detectors. Lastly, a prototype preclinic PET imager was constructed with 12 optimized detectors. The point source experiment was performed and an excellent spatial resolution (axial: 0.56 mm, tangential: 0.46 mm, radial: 0.42 mm) was achieved with the proposed high-performance PET detectors.