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The incidence of oropharyngeal cancer induced by human papillomavirus (HPV) infection is steadily increasing in developed countries. These tumors are more chemoradiosensitive and have a better prognosis than HPV-negative one. In addition, they occur in younger and better-off patients with longer life expectancy. Current radiotherapy and chemotherapy protocols are currently being questioned as they may expose HPV-positive patients to excessive treatment and unnecessary toxic effects. Less intensive treatment regimens could possibly achieve similar efficacy with lower toxicity and improved quality of life. The aim of this work was to summarize the knowledge on these tumors and their implications for radiation oncologists. In this update, we will discuss ongoing de-escalation trials and highlight the issues raised by these studies. We will also comment on the results of recently published de-intensification studies. Three main strategies are analyzed in the present article: the de-escalation of the drug associated with radiotherapy, the de-escalation of the radiotherapy dose (in concomitant chemoradiotherapy, after induction chemotherapy, in a postoperative setting) and de-escalation of radiation target volumes. Our findings ultimately indicate that clinicians should not change the management of oropharyngeal cancer patients outside of clinical trials.

Forecasting landslide displacement is an important issue in engineering geology. In this field, it is difficult to accurately forecast the displacement of the step point of a step-type landslide. In this study, a novel grey multivariate model is proposed for forecasting landslide displacement. The proposed model transforms the original sequence by using the Hausdorff derivative operator, determines the model parameters by using the particle swarm optimization algorithm, and uses the trapezoidal integral formula to calculate the predicted value. Two numerical examples show that the average absolute relative error and mean squared error of the proposed model are smaller than those of the recursive discrete multivariate grey model and the multivariable grey model with structure compatibility. The proposed model is used to forecast the displacement of the Bazimen landslide in the Three Gorges Reservoir area of China. The previous month’s displacement, precipitation, and change in the reservoir water level are used as input variables. The results show that the performance of the proposed model is superior to that of the extreme learning machine model. This paper provides an effective method for forecasting displacement of the step point of a step-type landslide.

This paper presents all-dielectric materials used to 3D print coupons with spatially varying dielectric permittivity and possessing high dielectric anisotropy. The coupons were directly printed through a dual-filament fused deposition modelling technique utilizing bespoke feedstock filament comprised a polymer-based micro-ceramic composite with controlled permittivity and loss. By designing the arrangement of both high and low permittivity filament materials in the printed coupons, the microwave operating frequency and magnitude of Mie-type resonances could be manipulated to provide metamaterial-like characteristics. Keywords: Additive manufacturing, Fusion deposition, Dielectric composites, Metamaterials

The degradation characteristics of MOCVD grown InGaAsP/InGaAs dual junction solar cells, irradiated by 1 MeV electron, 3 MeV and 10 MeV proton, have been investigated. Main electrical and optical properties of solar cell degraded seriously with the increase of irradiation fluences due to the irradiation induced defects which are acting as non-radiative recombination centers in the active layers of the solar cell. The remaining factor of P m a x is 0.67, 0.53 and 0.51 for 1 MeV electron, 10 MeV proton, and 3 MeV proton irradiation, respectively, when the displacement damage dose (DDD) is 3 . 16 × 1 0 10 MeV/g. The degradation of external quantum efficiency (EQE) of each subcell mainly occurred in the long wavelength region, the integrated current density J s c of InGaAsP and InGaAs subcells degraded more seriously upon 3 MeV and 10 MeV proton irradiation comparing to 1 MeV electron irradiation. The InGaAsP subcell turned out to be the current limiting unit due to the lower J s c before and post irradiation. By applying equivalent displacement damage dose model, the relative damage coefficient for 3 MeV proton to 10 MeV proton and 1 MeV electron to 10 MeV proton have been calculated.

Low-temperature (T = 30 K) photoluminescence (PL) and post thermal annealing effects on 150 KeV proton irradiated GaInAsN bulk, single quantum well and triple quantum well structures (Eg ~ 1.0 eV) have been investigated. The nitrogen proportion of the samples was confirmed by high-resolution X-ray diffraction (HR-XRD) measurement as 0.26%, 0.30% and 0.20% for GaInAsN bulk, SQW, and MQW samples, respectively. The result shows that the PL intensity of GaInAsN materials degraded seriously by proton irradiation. The PL intensity enhancement were observed for all three types of sample after thermal annealing at 650 °C for 5 min, and MQW sample was recovered by the factor bigger than 100. The irradiation induced red-shift and thermal annealing induced blue-shift phenomena were analyzed by SRIM simulation result and theoretical models of InGaAs band structure.

Higher areal density for magnetic recording is needed to provide larger storage capacities on harddisk drives. However, as the recording bit size of traditional magnetic recording materials (such as Co/Cr) approaches 10 nm, the magnetic direction of each recording bit would become unstable at room temperature due to thermal fluctuation. To solve this problem, efforts have been made using two methods: one method is to replace the disk media with new materials possessing higher magnetic anisotropy which would lead to better thermal stability; and the second one is to employ different configurations for the recording layer. FePt with patterned media configuration is a combination of these two methods. In this paper we review some novel and interesting methods of patterning FePt for magnetic recording, including thermal patterning, self-assembly patterning, and lithography patterning.

The elevated temperature deformation behavior of a 30 vol.%ZrC p /W composite was tested on a Gleeble-1500D thermo-mechanical simulation device under a uniaxial compressive load. The micro-failure behavior of the composite is strongly affected by the adhesive strength of ZrC/W interface and the distribution of ZrC particles. The computational results by EET theory indicate that the adhesive strength of (Zr, W)C interface is higher than that of ZrC. The microcrack initiation and propagation mechanism varies with the deformation temperature. TEM results show that the initiation and propagation of the microcracks occur in three steps in 1300–1600 °C.

The Tianyang Lake in Leizhou Peninsula is an enclosed crater formed during the Early to Middle Pleistocene. Over 200 m of diatomaceous mud and clay were deposited in the last 400,000 years, providing a continuous Middle and Late Quaternary lacustrine sequence for paleoenvironmental studies. The pollen record spans the last four glacial–interglacial cycles equivalent to Oxygen Isotope Stages (OIS) 10 to 1. During most of the glacial phases, Fagaceous monsoon forest was replaced by altitudinal vegetation, indicating a regional landscape transformation on the peninsula. The montane forest reached down to the lowland by at least 600 m during the OIS 6 and 8 in a cool and relatively wet condition, with temperature estimated to be more than 4°C lower than present. A further lowering of the montane forest belts by about 800–1000 m occurred in the OIS 4–2, as implied by the appearance of many temperate elements. During the Last Glacial Maximum, this mixed forest subsequently gave way to the Poaceae grassland, a savanna vegetation type favored by drier and cooler climatic conditions. This drastic change implies a more significant drop in temperature and precipitation than the previous three glacial periods (OIS 10, 8 and 6). It is thus inferred that the weakening of summer monsoon was more significant towards the end of the Late Pleistocene particularly during the Last Glacial Maximum (LGM).

More and more useful spectral information has been supplied to geoscientists from sophisticated space sensors with increasing detecting ability. Because the quality of spectral information depends on its sensor characteristics, sensor development is the key to remote sensing techniques. As an Earth observation space sensor the German MOMS-2P (Modular Optoelectronic Multispectral Stereo Scanner) was launched May 1996 aboard the PRIRODA Module docked on the Russian MIR Space Station in a preoperational mission for about three year duration. Technical features of the Sensor are three-line along-track stereo imaging, high spatial and spectral resolution, optimized multispectral and panchromatic bands and combination of stereo and multispectral imaging. The advanced sensor on the MIR-station can receive data covering the earth surface from N51.6° to S51.6°. This paper gives a critical review of the new generation of optical satellite sensors for earth observation, with special emphasis on the technical development of the sensor MOMS-2P and demonstrates newly acquired MOMS images that can be applied to many fields of thematic investigations.

Dopamine is a neurotransmitter crucial for movement, mood, drug addiction and many neural degeneration diseases including Parkinson's disease. Micro electrochemical carbon fiber microelectrode (CFE) can record dopamine release from brain in vivo. Stimulation action potentials (APs) induced secretion of dopamine in mouse brain striatum in vivo. The stimulus pattern is defined as AP code [N, m, f, d] (N = total stimulating number, m = burst-number, f = frequency, d = inter-burst interval) (Duan et al, JNS, 2003). In wide type mice (WT), with fixed AP number N, the evoked dopamine release was strongly modulated by code parameters m, f and d. In contrast to N and f, which regulate dopamine release by [Ca2+]i accumulation, m and/or d may modulate secretion by recycling vesicle pool. To test this hypothesis, we used a knockin mice (KI) with the dopamine transporter (DAT) insensitive to cocaine (Chen et al, PNAS, 2006). In KI vs. WT mice, both amplitude and kinetics of dopamine release was drastically changed following given stimulation AP code. The effect of AP burst number ([144, m, 80Hz, 0.5s],m = 1 vs. 16), or “m-effect”, on dopamine release is increased by > 400% in KI vs. WT mice. As expected, cocaine increased AP-induced dopamine release for blocking DAT in WT but not KI mice. Surprisingly, the presynaptic vesicle recycling is also altered by cocaine in WT vs. KI mice, as revealed by reduced “m-effect” in KI mice. We propose that cocaine affects not only DAT, but also presynaptic dopamine vesicle pool in striatum in mice.Supported by grant from China NSFC and “973” program 0