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Climate is critically affected by aerosols, which alter cloud lifecycles and precipitation distribution through radiative and microphysical effects. In this study, aerosol and cloud property datasets from MODIS (Moderate Resolution Imaging Spectroradiometer), onboard the Aqua satellite, and surface observations, including aerosol concentrations, raindrop size distribution, and meteorological parameters, were used to statistically quantify the effects of aerosols on low-level warm-cloud microphysics and drizzle over northern Taiwan during multiple fall seasons (from 15 October to 30 November of 2005–2017). Our results indicated that northwestern Taiwan, which has several densely populated cities, is dominated by low-level clouds (e.g., warm, thin, and broken clouds) during the fall season. The observed effects of aerosols on warm clouds indicated aerosol indirect effects (i.e., increased aerosol loading caused a decrease in cloud effective radius (CER)), an increase in cloud optical thickness, an increase in cloud fraction, and a decrease in cloud-top temperature under a fixed cloud water path. Quantitatively, aerosol–cloud interactions (ACI=-∂ln⁡CER∂ln⁡α|CWP, changes in CER relative to changes in aerosol amounts) were 0.07 for our research domain and varied between 0.09 and 0.06 in the surrounding remote (i.e., ocean) and polluted (i.e., land) areas, respectively, indicating aerosol indirect effects were stronger in the remote area. From the raindrop size distribution analysis, high aerosol loading resulted in a decreased frequency of drizzle events, redistribution of cloud water to more numerous and smaller droplets, and reduced collision–coalescence rates. However, during light rain (≤1 mm h−1), high aerosol concentrations drove raindrops towards smaller droplet sizes and increased the appearance of drizzle drops. This study used long-term surface and satellite data to determine aerosol variations in northern Taiwan, effects on clouds and precipitation, and observational strategies for future research on aerosol–cloud–precipitation interactions.

Glioblastoma is a common intracranial malignancy that is extremely harmful to human life and health. Various microRNAs (miRNAs) have been reported to be involved in the progression of glioblastoma, except miR-381. Therefore, the purpose of this study is to investigate the role of miR-381 in glioblastoma.The expression of miR-381 and LEF1 (lymphoid enhancer-binding factor-1) was quantified using quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) and Western blot analysis. Transwell and Dual-Luciferase reporter assays were used to investigate the regulatory mechanism of miR-381/LEF1 in glioblastoma.Downregulation of miR-381 was observed in A172 cells. In addition, the overexpression of miR-381 restrained migration and invasion of glioblastoma cells. Furthermore, overexpression of miR-381 inhibited epithelial-mesenchymal transition (EMT) in A172 cells. Further, miR-381 was confirmed to directly target LEF1 and negatively regulates its expression in glioblastoma cells. Downregulation of LEF1 also inhibited cell migration, invasion, and EMT in glioblastoma cells. More importantly, the upregulation of LEF1 abolished the inhibitory effect of miR-381 in glioblastoma cells.MiR-381 inhibits cell metastasis and EMT in glioblastoma by suppressing LEF1 expression.

L-ascorbate (AsA; Vitamin C) is an anti-and pro-oxidant phytochemical essential for the proper functioning of the human body. Field grown tomato fruit (Solanum lycopersicum) contain substantial amounts of AsA. When grown in the greenhouse, tomato fruit typically have low levels of AsA. Light is the major regulatory abiotic factor for AsA in plants. The introduction of light emitting diodes (LED) in horticulture provides the opportunity for improving quality of plant products. AsA levels of tomato fruit increase with additional light applied to the plant. In this work we examine the effects of irradiance on AsA levels of tomato fruit when light is applied to the fruit. Detached tomato fruit were treated with different irradiance levels provided by LEDs in a climate controlled environment. Tomato fruit treated with 263 μmol m-2 s-1 of white light for 13 days contained 32% more AsA than fruit kept at lower irradiances or in darkness. The light induced biosynthesis of AsA and the role of soluble carbohydrates in AsA regulation is discussed.

Synopsis Spectral line profile of Ti XII 11.64 nm was measured using spatio-temporally resolved laser-produced plasma technique. The electron density of laser-produced Ti plasmas was calculated based on the spectral line Stark broadening of highly charged ions.

Synopsis Laser-produced chromium (Cr) plasmas have been measured by using a temporal-spatially resolved laser-produced plasma emission spectroscopy technique. The emission peaks in the wavelength range of 6.5-15 nm were identified from the 3p-4d, 5d, and 3p-4s transition lines from Cr5+ to Cr10+ ions with aid of Cowan and Flexible Atomic Code (FAC) atomic structure calculations, and through comparative analysis between experimental and simulated spectra.

One of fundamental aims of extreme ultraviolet (EUV) lithography is to maximize brightness or conversion efficiency of laser energy to radiation at specific wavelengths from laser produced plasmas (LPPs) of specific elements for matching to available multilayer optical systems. Tin LPPs have been chosen for operation at a wavelength of 13.5 nm. For an investigation of EUV radiation of laser-produced tin plasmas, it is crucial to study the related atomic processes and their evolution so as to reliably predict the optimum plasma and experimental conditions. Here, we present a simplified radiation hydrodynamic model based on the fluid dynamic equations and the radiative transfer equation to rapidly investigate the evolution of radiation properties and dynamics in laser-produced tin plasmas. The self-absorption features of EUV spectra measured at an angle of 45° to the direction of plasma expansion have been successfully simulated and explained, and the evolution of some parameters, such as the plasma temperature, ion distribution and density, expansion size and velocity, have also been evaluated. Our results should be useful for further understanding of current research on extreme ultraviolet and soft X-ray source development for applications such as lithography, metrology and biological imaging.

BACKGROUND: Thitarodes larvae are the host of the caterpillar fungus Ophiocordyceps sinensis. Low temperature is the main environmental limitation for larvae growth.To better understand the cold adaption process in T. pui larvae, the expression patterns of trehalose-6-phosphate synthase (TpTPS), heat shock protein 70 (TpHSP70), and heat shock protein 90 (TpHSP90) were investigated upon short and long-term exposure to 0°C.The 6th instar T. pui larvae were collected in July 2013. TpTPS was firstly sequenced and expression patterns of TpTPS, TpHSP70 and TpHSP90 were investigated using quantitative PCR.Full-length cDNA of TpTPS was 3,012 bp, with an open reading frame of 2,472 bp and an encoding protein of 823 amino acids. TpTPS up-regulation was induced by cold exposure. TpHSP70 expression is altered by cold exposure, but remained low. TpHSP90 expression was obviously up regulated in long-term cold stimulation.All three genes (TpTPS, TpHSP70 and TpHSP90) have likely contributed to cold tolerance in T. pui larvae, TpTPS and TpHSP90 potentially being more important.

This study aimed to compare three different surgery approaches for pituitary adenoma excision. A total of 162 patients underwent pituitary adenoma excision through the sphenoid sinus approach. Among patients, five underwent the sublabio-septo-sphenoidal approach (abbreviated as "sublabio approach"), seven underwent the sphenoid sinus approach and 150 underwent the nasal septum approach. The operative cases that underwent the sublabio approach showed severe surgical trauma because of the complicated operation procedure. The sphenoid sinus approach was relatively easy to operate, but the procedure may confuse an inexperienced operator, which occurred in two out of seven cases in our study. The anatomical landmark was clearer under the nasal septum approach than the other approaches. Thus, operators were less likely to make mistakes during the nasal septum operation. In our study, a success rate of 100% was obtained for the 68 patients who underwent nasal septum operation. The nasal septum approach was suitable for most patients with pituitary adenoma. The hierarchy of the anatomy was distinctive and easily controlled. Thus, the entire nasal septum operation was relatively safe, effective and minimally invasive and can be completed by an operator with sufficient anatomical knowledge and operation skill.

Getting an accurate cloud cover state is a challenging task. In the past, traditional two-dimensional red-to-blue band methods have been widely used for cloud detection in total sky images. By analyzing the imaging principle of cameras, green channel has been selected to replace the 2-D red-to-blue band for total sky cloud detection. The brightness distribution in a total sky image is usually non-uniform, because of forward scattering and Mie scattering of aerosols, which results in increased detection errors in the circumsolar and near-horizon regions. This paper proposes an automatic cloud detection algorithm, "green channel background subtraction adaptive threshold" (GBSAT), which incorporates channel selection, background simulation, computation of solar mask and cloud mask, subtraction, adaptive threshold, and binarization. Several experimental cases show that the GBSAT algorithm is robust for all types of test total sky images and has more complete and accurate retrievals of visual effects than those found through traditional methods.

SUMMARY New methods for the treatment of solar radiative transfer through overlapping and inhomogeneous clouds are presented. First, a new approach to cloud overlap is shown. For the adjacent cloud blocks, the traditional maximum overlap can be relaxed to a mixture of maximum and random overlap treatments for layers that are adjacent but not fully correlated. Second, a new radiative-transfer algorithm has been developed to deal with these various cloud overlap circumstances that is simple enough for implementation in a general-circulation model (GCM). When compared to appropriate benchmark calculations, we find that this new method can produce accurate results in heating rates and fluxes with relative errors generally less than 8%. Third, a new and very simple approach to treating radiative transfer through a cloud with horizontal subgrid-scale inhomogeneities is developed. This approach uses an optical-depth scaling technique to represent the subgrid-scale inhomogeneity. Finally, by combining all of the above elements, we provide a new algorithm for the combined treatment of cloud overlap and inhomogeneity and we show that it yields very reasonable accuracies for heating rates and fluxes. Through benchmark comparisons, we show that this new algorithm provides significant improvement over existing schemes in GCMs.

A metal-isolator-metal (MIM) metamaterial absorber with embedded graphene shows tunable at mid-infrared frequency regime. We report tunable absorption spectra of the MIM structure for different Fermi levels of graphene.

Mineral dust aerosols often observed over California in winter/spring, associated with long-range transport from Asia and Sahara, have been linked to enhanced precipitation based on observations. Local anthropogenic pollution, on the other hand, was shown in previous observational and modeling studies to reduce precipitation. Here we incorporate recent developments in ice nucleation parameterizations to link aerosols with ice crystal formation in a spectral-bin cloud microphysical model coupled with the Weather Research and Forecasting (WRF) model, to examine the relative and combined impacts of dust and local pollution particles on cloud properties and precipitation type and intensity. Simulations are carried out for two cloud cases with contrasting meteorology and cloud dynamics that occurred on 16 February (FEB16) and 2 March (MAR02) from the CalWater 2011 field campaign. In both cases, observations show the presence of dust or dust/biological particles in a relative pristine environment. The simulated cloud microphysical properties and precipitation show reasonable agreement with aircraft and surface measurements. Model sensitivity experiments indicate that in the pristine environment, the dust/biological aerosol layers increase the accumulated precipitation by 10–20% from the Central Valley to the Sierra Nevada Mountains for both FEB16 and MAR02 due to a 40% increase in snow formation, validating the observational hypothesis. Model results show that local pollution increases precipitation over the windward slope of the mountains by few percent due to increased snow formation when dust is present but reduces precipitation by 5–8% if dust is removed on FEB16. The effects of local pollution on cloud microphysics and precipitation strongly depend on meteorology including the strength of the Sierra Barrier Jet, and cloud dynamics. This study further underscores the importance of the interactions between local pollution, dust, and environmental conditions for assessing aerosol effects on cold season precipitation in California.

Utilizing the unique characteristics of the cloud over the Southeast Pacific (SEP) off the coast of Chile during the VOCALS field campaign, we validated satellite remote sensing of cloud microphysical properties against in situ data from multi-aircraft observations, and studied the extent to which these retrieved properties are sufficiently constrained and consistent to reliably quantify the influence of aerosol loading on cloud droplet sizes. After constraining the spatial-temporal coincidence between satellite retrievals and in situ measurements, we selected 17 non-drizzle comparison pairs. For these cases the mean aircraft profiling times were within one hour of Terra overpass at both projected and un-projected (actual) aircraft positions for two different averaging domains of 5 km and 25 km. Retrieved quantities that were averaged over a larger domain of 25 km compared better statistically with in situ observations than averages over a smaller domain of 5 km. Validation at projected aircraft positions was slightly better than un-projected aircraft positions for some parameters. Overall, both MODIS-retrieved effective radius and LWP were larger but highly correlated with the in situ measured effective radius and LWP. The observed effective radius difference between the two decreased with increasing cloud drop number concentration, and increased with increasing cloud geometrical thickness. Also, MODIS retrievals for adiabatic clouds agreed better with the in situ measurements than for sub-adiabatic clouds. Our validation and sensitivity analysis of simulated retrievals demonstrate that both cloud geometrical thickness and cloud adiabaticity are important factors in satellite retrievals of effective radius and cloud drop number concentration. The large variabilities in cloud geometric thickness and adiabaticity, the dependencies of cloud microphysical properties on both quantities (as demonstrated in our sensitivity study of simulated retrievals), and the inability to accurately account for either of them in retrievals lead to substantial uncertainties and biases in satellite retrieved cloud effective radius, cloud liquid water path, and cloud drop number concentration. However, strong correlations between satellite retrievals and in situ measurements suggest that satellite retrievals of cloud effective radius, cloud liquid water path, and cloud drop number concentration can be used to investigate aerosol indirect effects qualitatively.

The major pathobiological mechanisms of IR injury include excitotoxicity, oxidative stress, and inflammation. TF3, a major constituent of black tea, possesses biological functions such as anti-oxidative and anti-inflammatory activities. The purpose of this study was to verify the neuronal protective potential of TF3 and its mechanisms against cerebral IR injury in rats. TF3 administration (10 and 20 mg.kg-1) ameliorated the infarct volume. TF3 also decreased the content of MDA and NO. TF3 significantly increased the activity of SOD and GSH-Px, which were reduced by IR injury. Administration of TF3 decreased mRNA and protein expression of COX-2 and iNOS. DNA binding and Western blotting revealed an increase in NF-kappaB activation and IkappaB depletion in IR brain tissue. Pretreatment with TF3 markedly inhibited IRinduced increase in nuclear localization of NF-kappaB, and preserved IkappaB in the cytoplasm. The results show that TF3 exerts protective effects against cerebral IR injury by reducing oxidative stress and modulating the NF-kappaB activation.

The ARM Climate Research Facility’s (ACRF) Aerial Vehicle Program (AVP) will deploy an intensive cloud and aerosol observing system to the ARM North Slope of Alaska (NSA) locale for a five week Indirect and Semi-Direct Aerosol Campaign (ISDAC) during period 29 March through 30 April 2008. The deployment period is within the International Polar Year, thus contributing to and benefiting from the many ancillary observing systems collecting data synergistically. We will deploy the Canadian National Research Council Convair 580 aircraft to measure temperature, humidity, total particle number, aerosol size distribution, single particle composition, concentrations of cloud condensation nuclei and ice nuclei, optical scattering and absorption, updraft velocity, cloud liquid water and ice contents, cloud droplet and crystal size distributions, cloud particle shape, and cloud extinction. In addition to these aircraft measurements, ISDAC will deploy two instruments at the ARM site in Barrow: a spectroradiometer to retrieve cloud optical depth and effective radius, and a tandem differential mobility analyzer to measure the aerosol size distribution and hygroscopicity. By using many of the same instruments used during Mixed-Phase Arctic Cloud Experiment (M-PACE), conducted in October 2004, we will be able to contrast the arctic aerosol and cloud properties during the fall andmore » spring transitions. The aerosol measurements can be used in cloud models driven by objectively analyzed boundary conditions to test whether the cloud models can simulate the aerosol influence on the clouds. The influence of aerosol and boundary conditions on the simulated clouds can be separated by running the cloud models with all four combinations of M-PACE and ISDAC aerosol and boundary conditions: M-PACE aerosol and boundary conditions, M-PACE aerosol and ISDAC boundary conditions, ISDAC aerosol and M-PACE boundary conditions, and ISDAC aerosol and boundary conditions. ISDAC and M-PACE boundary conditions are likely to be very different because of the much more extensive ocean water during M-PACE. The uniformity of the surface conditions during ISDAC greatly simplifies the objective analysis (surface fluxes and precipitation are very weak), so that it can largely rely on the European Centre for Medium-Range Weather Forecasts analysis. The aerosol measurements can also be used as input to the cloud models and to evaluate the aerosol retrievals. By running the cloud models with and without solar absorption by the aerosols, we can determine the semidirect effect of the aerosol on the clouds.« less

The Cloud and Land Surface Interaction Campaign is a field experiment designed to collect a comprehensive data set that can be used to quantify the interactions that occur between the atmosphere, biosphere, land surface, and subsurface. A particular focus will be on how these interactions modulate the abundance and characteristics of small and medium size cumuliform clouds that are generated by local convection. These interactions are not well understood and are responsible for large uncertainties in global climate models, which are used to forecast future climate states. The campaign will be conducted from June 8 to June 30, 2007, at the U.S. Department of Energy’s Atmospheric Radiation Measurement Climate Research Facility Southern Great Plains site. Data will be collected using eight aircraft equipped with a variety of specialized sensors, four specially instrumented surface sites, and two prototype surface radar systems. The architecture of Cloud and Land Surface Interaction Campaign includes a high-altitude surveillance aircraft and enhanced vertical thermodynamic and wind profile measurements that will characterize the synoptic scale structure of the clouds and the land surface within the Atmospheric Radiation Measurement Climate Research Facility Southern Great Plains site. Mesoscale and microscale structures will be sampled with a variety of aircraft,more » surface, and radar observations.« less

The Cloud and Land Surface Interaction Campaign (CLASIC) will be conducted from June 8 to June 30, 2007, at the U.S. Department of Energy’s Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) Southern Great Plains (SGP) site. Data will be collected using eight aircraft equipped with a variety of specialized sensors, four specially instrumented surface sites, and two prototype surface radar systems. The architecture of CLASIC includes a high-altitude surveillance aircraft and enhanced vertical thermodynamic and wind profile measurements that will characterize the synoptic scale structure of the clouds and the land surface within the ACRF SGP site. Mesoscale and microscale structures will be sampled with a variety of aircraft, surface, and radar observations. An overview of the measurement platforms that will be used during the CLASIC are described in this report. The coordination of measurements, especially as it relates to aircraft flight plans, will be discussed in the CLASIC Implementation Plan.

The Chinese 1992 staging system for nasopharyngeal carcinoma (NPC) has been widely adopted in mainland China since 1992. The fifth edition of the International Union Against Cancer (UICC) TNM classification defines new rules for classifying NPC. The current study compares the two in predicting NPC prognosis.Four hundred eleven NPC patients, most of whom had disease of undifferentiated histologic type and were treated in a constant fashion and with definitive intent with radiation therapy alone, entered this comparative study. The patients were restaged according to the rules of the fifth edition of the UICC staging manual and the Chinese 1992 staging system.In the opinion of the authors, the predictive power of the Chinese 1992 T classification was superior. Conversely, the authors felt that the UICC N classification was more reasonable. The patients were categorized more evenly by the UICC stages than by the Chinese 1992 stages. The 5-year disease specific survival rates for patients in corresponding stages of both systems were almost identical despite differences in the criteria defining T and N classifications. Statistical analysis showed that the agreement rate was 72%. There were some agreement and correlation between the two staging systems.Both systems are essentially similar. Each system appears to have some subtleties that could improve the outcome prediction of the other system if the two were somehow combined. However, it appeared to the authors that the UICC system was slightly better.

Angiogenesis is essential for tumor growth and metastasis. Vascular endothelial growth factor (VEGF) is the most potent angiogenic factor identified to date. The authors investigated the correlation between the levels of serum VEGF (S-VEGF) in patients with nasopharyngeal carcinoma (NPC) and disease progression.The sera from 65 male patients with nonmetastatic NPC, 22 male patients with metastatic NPC, and 27 healthy male volunteers were obtained. A quantitative enzyme-linked immunosorbent assay was performed to measure the concentrations of S-VEGF in the sera.The mean S-VEGF levels were 371.0 pg/mL(-1) (range, 128.5-691.1 pg/mL(-1)) for healthy controls, 375.6 pg/mL(-1) (range, 72.9-1202.5 pg/mL(-1)) for patients with nonmetastatic NPC, and 958.6 pg/mL(-1) (range, 264.4-3744.9 pg/mL(-1)) for patients with metastatic NPC. The mean S-VEGF level in patients with metastatic NPC was significantly higher than in either patients with nonmetastatic NPC (P0.001) or healthy controls (P0.001). However, there was no statistical difference between these results for healthy controls and patients with nonmetastatic NPC. At the level of 900 pg/mL(-1), S-VEGF indicated distant dissemination of NPC with a specificity of 95.4%, a sensitivity of 31.8%, a positive predictive value of 70.0%, and a negative predictive value of 80.5%. No significant differences in the levels of S-VEGF were found among various T classifications, N classifications, and clinical stages of nonmetastatic NPC.The levels of S-VEGF were significantly elevated in male patients with metastatic NPC. These levels did not correlate with locoregional progression of NPC. The usefulness of detecting S-VEGF in the early diagnosis of NPC appears to be limited.

Tuberculosis in the abdominal lymph nodes may be difficult to distinguish from lymphomas. This study evaluated specific CT imaging criteria for differentiating these entities.We retrospectively reviewed the anatomic distribution and CT enhancement patterns of disease in 69 patients, 26 (38%) with tuberculosis and 43 (62%) with untreated lymphomas involving abdominal lymph nodes. Of the patients with tuberculosis, five (19%) had disseminated disease and 21 (81%) had nondisseminated disease. Of the patients with lymphomas, 16 (37%) had Hodgkin's disease and 27 (63%) had non-Hodgkin's lymphoma.Disseminated and nondisseminated tuberculosis involved predominantly lesser omental, mesenteric, anterior pararenal, and upper paraaortic lymph nodes. Lower paraaortic lymph nodes were involved more often in Hodgkin's disease (15 patients [94%]), non-Hodgkin's lymphoma (24 patients [89%]), and disseminated tuberculosis (five patients [100%]) than in nondisseminated tuberculosis (one patient [5%]). Mesenteric lymph nodes were involved more often in disseminated tuberculosis (four patients [80%]) and nondisseminated tuberculosis (11 patients [52%]) than in Hodgkin's disease (one patient [6%]) (p.01). Anatomic distribution was not different between disseminated tuberculosis and non-Hodgkin's lymphoma. Tuberculous lymphadenopathy commonly showed peripheral enhancement, frequently with a multilocular appearance, whereas lymphomatous adenopathy characteristically showed homogeneous attenuation (14 patients [87.5%] with Hodgkin's disease and 19 patients [70%] with non-Hodgkin's lymphoma [p.01]).Our findings indicate that the anatomic distribution and specific enhancement patterns of lymphadenopathy seen on contrast-enhanced CT can be useful in differentiating between tuberculosis and untreated lymphomas of the abdominal lymph nodes.