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The non-uniform beam filling bias in Doppler velocity measurements from a spaceborne precipitation radar is investigated. A simple derivation of the already-known formula that relates the bias to the along-track gradient of measured radar reflectivity in dBZ is shown. From the formula, the uncertainty of bias correction due to discretization is discussed. The error is shown to be proportional to the square of the spacing for discretization, and is related to the third moment of the distribution of the radar reflectivity convolved with the antenna pattern. The effectiveness of averaging is also shown from a simulation.

A rapid on-bead convergent method for preparing branched peptides was reported. Linear peptides were prepared on Dbz resin and ligated various branched cores, including lysine dendrons and other dendritic compounds. Alongside microwave irradiation

The elucidation of characteristics of cumulonimbus clouds that cause lightning is important for predicting thunderstorm development. These characteristics, with and without lightning, were observed during a day (in 2010) of severe thunderstorms and lightning in Japan and statistically analyzed using radar observations with cell tracking. Observed cells were categorized into a cell including cloud-to-ground lightning (CG) and intra-cloud lightning (CGIC), a cell containing only intra-cloud lightning (IC), and a cell without lightning (NoL). These cells were compared to the average and temporal evolution of radar observations. Out of the 265 cells generated, 103 were CGIC cells, 30 were IC cells, and 132 were NoL cells. Significant differences were detected between the averaged values of lifetime, size, echo top, vertically integrated liquid (VIL), maximum radar reflectivity, and radar reflectivity of each cell category, when the − 10 °C isotherm height was considered. The temporal evolution of CGIC cell characteristics revealed changes in radar reflectivity at 0 °C and − 10 °C that were synchronized with lightning activity. The VIL value was elevated only for CGIC cells and had the tendency to decrease with time as lightning activity. CGIC cells produced the highest echo top and maintained their height during their lifetime. To predict CG within 20 min using 35 dBZ radar reflectivity at − 30 °C as the criterion, a critical success index (CSI) of 0.82 and false alarm rate (FAR) of 0.64 were found to have the best prediction scores.

In this study, the pharmaceutical carbamazepine (CBZ) and the related molecule dibenzazepine (DBZ) are prepared on the Au(111) surface and visualized using scanning tunneling microscopy. Monolayers...

The flight forbidden area (FFA) in convective weather is an important information resource for aviation. Using the density-based spatial clustering of applications with noise (DBSCAN), convex hull function in OpenCV library and other methods, the generation and verification of FFA in convective weather based on real weather and trajectory data are proposed in this study. Four relationship classes between flight trajectories and FFA are defined and eight examples are conducted to investigate the impact of radar reflectivity threshold and safety margin on the accuracy of FFA. Judging from the results, 40 dBZ is a better radar reflectivity threshold for the generation of FFA in convective weather, as the proportion of samples that fly outside of FFA with 40 dBZ is higher than that with 35 dBZ, and the proportion of samples that fly inside of FFA with 40 dBZ is lower than that with 35 dBZ. In addition, the accuracy of FFA decreases rapidly with the increasing of safety margin and it is suggested that the safety margin should range from 7 to 15 km to get a more realistic FFA.

A new dual-frequency Doppler polarimetric cloud radar (DDCR), working at 35-GHz (Ka-band radar, wavelength: 8.6 mm) and 94-GHz (W-band radar, wavelength: 3.2 mm) frequencies, has been in operation at Yangbajing Observatory on the Tibetan Plateau (China) for more than a year at the time of writing. Calculations and field observations show that the DDCR has a high detection sensitivity of −39.2 dBZ at 10 km and −33 dBZ at 10 km for the 94-GHz radar and 35-GHz radar, respectively. The radar reflectivity measured by the two radars illustrates different characteristics for different types of cloud: for precipitation, the attenuation caused by liquid cloud droplets is obviously more serious for the 94-GHz radar than the 35-GHz radar (the difference reaches 40 dB in some cases), and the 94-GHz radar lost signals due to serious attenuation by heavy rainfall, while for clouds dominated by ice crystals where the attenuation significantly weakens, the 94-GHz radar shows better detection ability than the 35-GHz radar. Observations in the Tibetan region show that the 35-GHz radar is prone to missing cloud near the edge, such as the cloud-top portion, resulting in underestimation of the cloud-top height (CTH). Statistical analysis based on one year of observations shows that the mean CTH measured by the 94-GHz radar in the Tibetan region is approximately 600 m higher than that measured by the 35-GHz radar. The analysis in this paper shows that the DDCR, with its dual-frequency design, provides more valuable information than simpler configurations, and will therefore play an important role in improving our understanding of clouds and precipitation in the Tibetan region.

Tracking multiple maneuvering targets hidden in the Doppler blind zone (DBZ) is a challenging problem. To overcome the complicated problem, we proposed a tracker based on the multiple model probability hypothesis density (MM-PHD) filter. However, the PHD filter is only the first-order moment approximation of the multi-target Bayesian filter, and it cannot output track labels in principle. In order to improve the tracking performance, another novel tracker is proposed in this paper. To track multiple maneuvering targets, the proposed tracker is built on the latest multiple model generalized labeled multi-Bernoulli (MM-GLMB) filter. Moreover, it incorporates the minimum detectable velocity (MDV) to suppress the DBZ masking. Finally, a measurement-driven adaptive track initiation is introduced to address the fixed track initiation problem of the standard MM-GLMB filter. It is demonstrated through numerical examples that the proposed tracker outperforms the existing work significantly, especially in terms of both accuracy and robustness of cardinality estimation.

The thioester surrogate 3,4-diaminobenzoic acid (Dbz) facilitates the efficient synthesis of peptide thioesters by Fmoc chemistry solid phase peptide synthesis and the optional attachment of a solu...

The cloud cells are categorized into six categories based on the radar reflectivity data obtained from Hyderabad S-band radar for the excess (2013) and deficient (2014) summer monsoon seasons. Among these, three categories (pre-convective, PC:19–27.5 dBZ, convective-initiation, CI: 28–36.5 dBZ and convective-enhancement, CE:37–45.5 dBZ) constitute about 59–64% of the total cloud population and play a vital role in the total rainfall. The monsoons are classified into excess/deficient if the seasonal rainfalls are more/less by 10% from the climatological mean. The study showed that on the daily scale, occurrence of these cells is ubiquitous feature of this rain-shadow region. Persistent formation of cells is due to large scale monsoon circulation and solar heating. On the intraseasonal scale monsoon conditions are classified into active/break conditions based on rainfall activity. Prevalence of high moisture (> 80%) and upward vertical velocity (up to 200 hPa) are responsible for high occurrence of cells in the active conditions. The solar heating is conducive for formation of cells in the break monsoon conditions and in the afternoon hours. Mean rate of transition from lower to higher level of convection intensity is − 0.72. The clouds in the states of PC, CI and CE show maximum/minimum values in the local afternoon/morning hours. The linkages established using multivariate regression analysis between VL category cells and the large-scale dynamic parameters and solar heating showed dominant role of these processes in the statistical prediction of number of these cells. The spatio-temporal variability of these cells will be useful for understanding the evolution of convection and modeling studies.

Interpolation of ground-based radar measurements is required when mapping data from their native spherical coordinates to a Cartesian grid. For reflectivity the question arises as to whether this processing should be performed in units ofZ(mm6m−3) or dBZ. This study addresses this question using one year of data from three radars, operating in diverse climates across Australia. For each radar, a subset of 800 volume scans is processed to identify “triads”—groups of three consecutive gates with valid data—in each of the three coordinate directions: range, azimuth, and elevation. For every triad, the reflectivity at the central gate is estimated by linearly interpolating between the outer two gates in bothZand dBZ. The resulting values are then compared with the true reflectivity at the central gate to quantify the interpolation errors. For all three sites and in all three coordinate directions, we find that interpolation inZis more accurate on average, especially in regions of high reflectivity and strong reflectivity gradient (i.e., convective cores). However, interpolation in dBZis better in regions of low and monotonically increasing/decreasing reflectivity. It is therefore recommended that reflectivities be converted from dBZtoZprior to interpolation except when identifying echo-top height or other low-reflectivity boundaries.

Alternative promoter usage generates long and short isoforms (DCLK1-L and DCLK1-S) of doublecortin-like kinase-1 (DCLK1). Tight control of Notch signaling is important to prevent and restitute inflammation in the intestine. Our aim was to investigate whether Notch1–DCLK1 axis regulates the mucosal immune responses to infection and whether this is phenocopied in human models of colitis. In the FFPE (formalin-fixed paraffin-embedded) sections prepared from the colons of ulcerative colitis (UC) and immune-mediated colitis (IRAEC) patients, expression of DCLK1 isoforms correlated positively with Notch1 and negatively with a transcriptional repressor, FoxD3 (Forkhead Box D3). DCLK1 protein staining in these sections was predominantly sub-epithelial (stromal) wherein DCLK1 co-localized with NICD, CD68, CD11c, and neutrophil elastase (NE). NE also co-stained with Citrullinated-H3 indicating the presence of neutrophil extracellular traps. In human neutrophils, elevated levels of DCLK1-S, CXCL-10, Ly6G, MPO, NE, and Notch1/2 in LPS-treated cells were inhibited when LPS was added in conjunction with Notch blocker dibenzazepine (DBZ; LPS + DBZ group). In CR-infected Rag1−/− mice, higher levels of DCLK1 in the colonic crypts were inhibited when mice received DBZ for 10 days coincident with significant dysbiosis, barrier disruption, and colitis. Concurrently, DCLK1 immunoreactivity shifted toward the stroma in CR + DBZ mice with predominance of DCLK1-S that coincided with higher Notch1 levels. Upon antibiotic treatment, partial restoration of crypt DCLK1, reduction in MPO activity, and increased survival followed. When intestinal epithelial cell-specific Dclk1-knockout (Dclk1ΔIEC) or Dclk1ΔIEC;Rag1−/− double knockout (DKO) mice were infected with CR and given a single dose of DBZ, they developed barrier defect and severe colitis with higher levels of stromal DCLK1-S, Ly6G, NE, and Notch1. We therefore propose that, by regulating the mucosal immune responses, the Notch–DCLK1 axis may be integral to the development of murine or human colitis.

Several gastrointestinal epithelial cells are involved in taste signal transduction. Although rodent tissues are extensively used as a human gut model, recent studies show that the chemical sensing system in rodents differs from that in humans. Nonhuman primates in biomedical research are valuable animal models to advance our understanding of biological responses in humans. The 3D organoid culture produces functional gastrointestinal epithelial cells in vitro and can be generated from animal and human tissues. Here, we report the generation of intestinal chemosensory cells from nonhuman primates, macaques, using an organoid culture system. We were able to maintain macaque intestinal organoids in the proliferation medium for more than six months. Upon switching to differentiation medium, we observed a drastic change in organoid morphology and chemosensory cell marker protein expression. This switch from proliferation to differentiation was confirmed by transcriptome analysis of the duodenum, jejunum, and ileum organoids. We further observed that the supplementation of culture media with interleukin (IL)-4 or the Notch inhibitor dibenzazepine (DBZ) accelerated terminal cell differentiation into chemosensory cells. Overall, we generated monkey intestinal organoids for the first time. These organoids are suitable for studying the function of primate chemosensory cells.

In this chapter, the output tracking of TVL system is investigated. For solving such an output-tracking problem, three different types of controllers are presented, i.e., the conventional controller, ZD controller and ZG controller. Simulation results with two illustrative examples show that such three types of controllers are feasible and effective for the output-tracking problem solving. Especially, the presented ZG controller is capable of conquering the DBZ problem of TVL system.

Disdrometer and condensation nuclei (CN) data are compared with operational polarimetric radar data for one multicell and one supercell storm in eastern Nebraska on 11 June 2018. The radar was located ~14.3 km from the instrumentation location and provided excellent observation time series with new low-level samples every 1&ndash, 2 min. Reflectivity derived by the disdrometer and radar compared well, especially in regions with high number concentration of drops and reflectivity &lt, 45 dBZ. Differential reflectivity also compared well between the datasets, though it was most similar in the supercell storm. Rain rate calculated by the disdrometer closely matched values estimated by the radar when reflectivity and differential reflectivity were used to produce the estimate. Concentration of CN generally followed precipitation intensity for the leading convective cell, with evidence for higher particle concentration on the edges of the convective cell associated with outflow. The distribution of CN in the supercell was more complex and generally did not follow precipitation intensity.

Chronic obstructive pulmonary disease (COPD) is the 3rd leading cause of death in the United States and is primarily caused by cigarette smoking. Increased numbers of mucus-producing secretory (“goblet”) cells defined as goblet cell metaplasia or hyperplasia (GCMH), contributes significantly to COPD pathophysiology. The objective of this study was to determine whether NOTCH signaling regulates goblet cell differentiation in response to cigarette smoke. Primary human bronchial epithelial cells (HBECs) from nonsmokers and COPD smokers were differentiated in vitro on air-liquid interface and exposed to cigarette smoke extract (CSE) for 7 days. NOTCH signaling activity was modulated using (1) the NOTCH/γ-secretase inhibitor Dibenzazepine (DBZ), (2) lentiviral over-expression of the NOTCH3-intracellular domain (NICD3) or (3) NOTCH3-specific siRNA. Cell differentiation and response to CSE were evaluated by qPCR, Western blotting, immunostaining and RNA-Seq. We found that CSE exposure of nonsmoker airway epithelium induced goblet cell differentiation characteristic of GCMH. Treatment with DBZ suppressed CSE-dependent induction of goblet cell differentiation. Furthermore, CSE induced NOTCH3 activation, as revealed by increased NOTCH3 nuclear localization and elevated NICD3 protein levels. Over-expression of NICD3 increased the expression of goblet cell associated genes SPDEF and MUC5AC, whereas NOTCH3 knockdown suppressed CSE-mediated induction of SPDEF and MUC5AC. Finally, CSE exposure of COPD airway epithelium induced goblet cell differentiation in a NOTCH3-dependent manner. These results identify NOTCH3 activation as one of the important mechanisms by which cigarette smoke induces goblet cell differentiation, thus providing a novel potential strategy to control GCMH-related pathologies in smokers and patients with COPD.

Objectives To investigate the role of dibenzazepine (DBZ) in promoting supporting cell (SC) proliferation and hair cell (HC) regeneration in the inner ear. Materials and Methods Postnatal day 1 wild‐type or neomycin‐damaged mouse cochleae were cultured with DBZ. Immunohistochemistry and scanning electron microscopy were used to examine the morphology of cochlear cells, and high‐throughput RNA‐sequencing was used to measure gene expression levels. Results We found that DBZ promoted SC proliferation and HC regeneration in a dose‐dependent manner in both normal and damaged cochleae. In addition, most of the newly regenerated HCs induced by DBZ had visible and relatively mature stereocilia bundle structures. Finally, RNA sequencing detected the differentially expressed genes between DBZ treatment and controls, and interaction networks were constructed for the most highly differentially expressed genes. Conclusions Our study demonstrates that DBZ can significantly promote SC proliferation and increase the number of mitotically regenerated HCs with relatively mature stereocilia bundles in the neonatal mouse cochlea by inhibiting Notch signalling and activating Wnt signalling, suggesting the DBZ might be a new therapeutic target for stimulating HC regeneration., Hair cell (HC) damage is the main cause of permanent hearing loss in mammals. To investigate the role of DBZ in the neonatal mouse cochlea, we cultured postnatal day 1 mouse cochleae with DBZ. We found that DBZ promoted SC proliferation and new HC generation in a dose‐dependent manner in both intact and damaged cochleae. In addition, most of the newly generated HCs induced by DBZ had visible and relatively mature stereocilia bundle structures. Our study demonstrates that DBZ can significantly promote SC proliferation and increase the number of mitotically regenerated HCs with relatively mature stereocilia bundles in the neonatal mouse cochlea by inhibiting Notch signalling and activating Wnt signalling, suggesting the DBZ might be a new therapeutic target for stimulating HC regeneration.

Summary Inhibition of Notch signaling has been shown to induce white to beige transformation of adipocytes and reduce the risk of obesity in mice. However, it remains unknown whether the metabolic benefits of Notch inhibition are dependent on uncoupling protein 1 (UCP1)-mediated thermogenesis and evolutionarily relevant in other mammalian species. Here we report the effect of Notch inhibition in adipocytes of pigs, which lost the UCP1 gene during evolution. Notch inhibition using a γ-secretase inhibitor dibenzazepine (DBZ) promoted beige adipogenesis and mitochondrial biogenic gene expression in porcine adipocytes. Moreover, encapsulation of DBZ into poly(lactide-co-glycolide) nanoparticles enabled rapid cellular internalization and enhanced bioactivity to achieve sustained Notch inhibition, thereby inducing beige-specific gene expression and reducing subcutaneous adipose tissue expansion in pigs. These results demonstrate for the first time a role of Notch signaling in regulating adipose plasticity in large animals, highlighting the therapeutic potential of targeting Notch signaling in obesity treatment., Graphical Abstract, Highlights • DBZ promotes beige adipogenesis and mitochondrial biogenesis in porcine adipocytes • Encapsulation of DBZ into NPs allows for efficient and sustained Notch inhibition • DBZ NPs induce upregulated beige-specific gene expression in porcine adipocytes • Local injection of DBZ NPs reduces subcutaneous adipose tissue expansion in pigs, Biological Sciences; Physiology; Cellular Physiology; Cell Biology

The results of investigation of convective cloud merging observed near Saint Petersburg are presented. Data obtained with a set of remote sensing instruments (radar, radiometer, and lightning location system) were analyzed. Rain gage network data are used. Clouds simulation is performed using a 1.5-dimensional nonstationary model. A method to calibrate the radar measurements to obtain precipitation characteristics using rain gage network data is developed. According to radar data, a 2-km increase in the cloud top height was observed after Cu merging, the maximum reflectivity of clouds increased at 10 dBZ, maximum rain intensity and rain flux increased by about two times. The increase in rainfall intensity is also corroborated by rain gage observations and numerical simulations. An increase in the intensity of lightning discharges during the merging is registered.

As the target organ for numerous pathogens, the lung epithelium exerts critical functions in health and disease. However, research in this area has been hampered by the quiescence of the alveolar epithelium under standard culture conditions. Here, we used human distal airway epithelial cells (DAECs) to generate alveolar epithelial cells. Long-term, robust growth of human DAECs was achieved using co-culture with feeder cells and supplementation with epidermal growth factor (EGF), Rho-associated protein kinase inhibitor Y27632, and the Notch pathway inhibitor dibenzazepine (DBZ). Removal of feeders and priming with DBZ and a cocktail of lung maturation factors prevented the spontaneous differentiation into airway club cells and instead induced differentiation to alveolar epithelial cells. We successfully transferred this approach to chicken distal airway cells, thus generating a zoonotic infection model that enables studies on influenza A virus replication. These cells are also amenable for gene knockdown using RNAi technology, indicating the suitability of the model for mechanistic studies into lung function and disease., Highlights • Long-term growth of DAECs was achieved using co-culture with feeder cells and compound supplementation. • DAECs treated with Notch inhibitors and growth factors differentiated towards alveolar epithelial cells. • Human and chicken DAECs support replication of different IAV strains. Imai-Matsushima et al. describe a method for stable culture of human and chicken distal airway epithelial cells (DAECs). Upon Notch inhibitor and growth factor supplementation these cells can generate alveolar epithelial cells. DAECs support IAV virus infection and are amenable to gene knockdown, enabling studies into lung function and respiratory infections.

Opposing activities of Notch and Wnt signaling regulate mucosal barrier homeostasis and differentiation of intestinal epithelial cells. Specifically, Wnt activity is essential for differentiation of secretory cells including Wnt3-producing Paneth cells, whereas Notch signaling strongly promotes generation of absorptive cells. Loss of caspase-8 in intestinal epithelium (casp8∆int) is associated with fulminant epithelial necroptosis, severe Paneth cell death, secondary intestinal inflammation, and an increase in Notch activity. Here, we found that pharmacological Notch inhibition with dibenzazepine (DBZ) is able to essentially rescue the loss of Paneth cells, deescalate the inflammatory phenotype, and reduce intestinal permeability in casp8∆int mice. The secretory cell metaplasia in DBZ-treated casp8∆int animals is proliferative, indicating for Notch activities partially insensitive to gamma-secretase inhibition in a casp8∆int background. Our data suggest that casp8 acts in the intestinal Notch network.

Inhibition of Notch signaling via systemic drug administration triggers conversion of white adipocytes into beige adipocytes (browning) and reduces adiposity. However, translation of this discovery into clinical practice is challenged by potential off-target side effects and lack of control over the location and temporal extent of beige adipocyte biogenesis. Here, we demonstrate an alternative approach to stimulate browning using nanoparticles (NPs) composed of FDA-approved poly(lactide-co-glycolide) that enable sustained local release of a Notch inhibitor (dibenzazepine, DBZ). These DBZ-loaded NPs support rapid cellular internalization and inhibit Notch signaling in adipocytes. Importantly, focal injection of these NPs into the inguinal white adipose tissue depots of diet-induced obese mice results in localized NP retention and browning of adipocytes, consequently improving the glucose homeostasis and attenuating body-weight gain of the treated mice. These findings offer new avenues to develop a potential therapeutic strategy for clinical treatment of obesity and its associated metabolic syndrome.

Accurate measurements of snow amounts by radar are very difficult to achieve. The inherent uncertainty in radar snow estimates that are based on the radar reflectivity factor Z is caused by the variability of snow particle size distributions and snow particle density as well as the large diversity among snow growth habits. In this study, a novel method for snow quantification that is based on the joint use of radar reflectivity Z and specific differential phase KDP is introduced. An extensive dataset of 2D-video-disdrometer measurements of snow in central Oklahoma is used to derive polarimetric relations for liquid-equivalent snowfall rate S and ice water content IWC in the forms of bivariate power-law relations S = and along with similar relations for the intercept N0s and slope Λs of the exponential snow size distribution. The physical basis of these relations is explained. Their multipliers are sensitive to variations in the width of the canting angle distribution and to a lesser extent the particles’ aspect ratios and densities, whereas the exponents are practically invariant. This novel approach is tested against the S(Z) relation using snow disdrometer measurements in three geographical regions (Oklahoma, Colorado, and Canada). Significant improvement in snow estimates relative to the traditional Z-based methods is demonstrated.

Background The nuclear receptor PPARγ is an effective pharmacological target for some types of metabolic syndrome, including obesity, diabetes, nonalcoholic fatty liver disease, and cardiovascular disease. However, the current PPARγ-targeting thiazolidinedione drugs have undesirable side effects. Danshensu Bingpian Zhi (DBZ), also known as tanshinol borneol ester derived from Salvia miltiorrhiza , is a synthetic derivative of natural compounds used in traditional Chinese medicine for its anti-inflammatory activity. Methods In vitro , investigations of DBZ using a luciferase reporter assay and molecular docking identified this compound as a novel promising PPARγ agonist. Ten-week-old C57BL/6J mice were fed either a normal chow diet (NCD) or a high-fat diet (HFD). The HFD-fed mice were gavaged daily with either vehicle or DBZ (50 mg/kg or 100 mg/kg) for 10 weeks. The gut microbiota composition was assessed by analyzing the 16S rRNA gene V3 + V4 regions via pyrosequencing. Results DBZ is an efficient natural PPARγ agonist that shows lower PPARγ-responsive luciferase reporter activity than thiazolidinediones, has excellent effects on the metabolic phenotype and exhibits no unwanted adverse effects in a HFD-induced obese mouse model. DBZ protects against HFD-induced body weight gain, insulin resistance, hepatic steatosis and inflammation in mice. DBZ not only stimulates brown adipose tissue (BAT) browning and maintains intestinal barrier integrity but also reverses HFD-induced intestinal microbiota dysbiosis. Conclusions DBZ is a putative PPARγ agonist that prevents HFD-induced obesity-related metabolic syndrome and reverse gut dysbiosis. General significance DBZ may be used as a beneficial probiotic agent to improve HFD-induced obesity-related metabolic syndrome in obese individuals.

In previous studies, remote sensing properties of hailstorms have been discussed using various spaceborne sensors. Relationships between hail occurrence and strong passive microwave brightness temperature depressions have been established. Using a 16-yr precipitation-feature database derived from the Tropical Rainfall Measuring Mission (TRMM) satellite, the performance of the TRMM Precipitation Radar and TRMM Microwave Imager is further investigated for hail detection. Detection criteria for hail larger than 19 mm are separately developed from Ku-band radar reflectivity and microwave brightness temperature properties of precipitation features that are collocated with surface hail reports over the southeastern and south-central United States. A threshold of 44 dBZ at −22°C is found to have the highest critical success index and Heidke skill score. The threshold of 230 K at 37 GHz yields the best scores among passive microwave properties. Using these two thresholds, global distributions of possible hail events are generated over 65°S–65°N using two years of observations from the Global Precipitation Measurement Core Observatory satellite. Differences in the derived hail geographical distributions are found between radar and passive microwave methods over tropical South America, the “Maritime Continent,” west-central Africa, Argentina, and South Africa. These discrepancies result from different vertical structures of the maximum radar reflectivity profiles over these regions relative to the southeastern and south-central United States, where the thresholds were established. Those differences generally led to overestimates in the tropics from the passive microwave methods, relative to the radar-based methods.

The results of analysis of long-term radar observations of hailstorms are presented. The dynamic characteristics of formation and development of hail cores in severe convective clouds are studied. The statistical sample of radar data included 314 hail cells; for each cell the temporal distributions of measured and computed major radar parameters were constructed using the automated system of acquisition, processing, and presentation of radar data. The most informative time characteristics of hail cores’ development and the interrelation between them were identified. The natural variability of hail core volume is demonstrated. The empirical dependence of the maximum hail core volume on the maximum radar reflectivity of a hailstorm was obtained.

Based on the structure of Dawson’s 3,4-diaminobenzoic acid (Dbz) linker designed for Fmoc solid-phase peptide-thioester synthesis, the 4-amino-3-nitrobenzoic acid [Dbz(NO2)] linker was developed for microwave-assisted synthesis. The Dbz(NO2) linker can be readily converted into the Dbz linker by on-resin reduction with SnCl2 after construction of the protected peptide resin. Although epimerization of C-terminal amino acid restricts the use of Dbz(NO2) linker to the synthesis of peptide-Gly-thioester, use of this linker can prevent side reactions that arise when Dbz or Dbz(Aloc) linkers are used in the microwave-assisted synthesis of Gly-rich peptides.

Characterization of precipitation is important for proper interpretation of rain information from remotely sensed data. Rain attenuation and radar reflectivity (Z) depend directly on the drop size distribution (DSD). The relation between radar reflectivity/rain attenuation and rain rate (R) varies widely depending upon the origin, topography, and drop evolution mechanism and needs further understanding of the precipitation characteristics. The present work utilizes 2 years of concurrent measurements of DSD using a ground-based disdrometer at five diverse climatic conditions in Indian subcontinent and explores the possibility of rain classification based on microphysical characteristics of precipitation. It is observed that both gamma and lognormal distributions are performing almost similar for Indian region with a marginally better performance by one model than other depending upon the locations. It has also been found that shape-slope relationship of gamma distribution can be a good indicator of rain type. The Z-R relation, Z = ARb, is found to vary widely for different precipitation systems, with convective rain that has higher values of A than the stratiform rain for two locations, whereas the reverse is observed for the rest of the three locations. Further, the results indicate that the majority of rainfall (>50%) in Indian region is due to the convective rain although the occurrence time of convective rain is low (

This paper uses the MaXPol dual-polarization radar data of WeiNing Meteorological Bureau of GuiZhou Province to analyze the hail weather process on September 13, 2019. The research shows that (1) Using the attenuation-corrected X-band data, it is analyzed by comparison method in the echo region and shows that the differential reflectivity (Zdr),the correlation coefficient (ρhv) are high but the differential phase (PhiDP) is low, when the reflectivity (Z) is 50 dBZ or more. (2) Particles of the process are classified by the fuzzy logic method with parameters of Z, Zdr, ρhv and PhiDP. (3) The hail region were identified from the radar echo map and found to be consistent with local weather phenomena.

Since 2015, the first batch of domestic dual polarization radars have been upgraded and put into operation in Yangjiang, Meizhou, Shaoguan and Guangzhou. In the early stage of polarization radar operation, due to the limitation of technology level, the polarization parameters are not stable, so it is necessary to make a preliminary analysis of the polarization parameters before using data. In this paper, the correlations of reflectivity (ZH), Signal-to-noise ratio(SNR), correlation coefficient (CC), differential reflectivity (ZDR), specific differential phase shift rate (KDP) are quantitatively evaluated by statistics and analysis of a typical stratiform cloud precipitation process observed by dual polarization radar. The results show that: (1) The system ZDR bias by using light rain is stable at about 0.1dB, which meets the accuracy requirements of ZDR (0.1-0.2dB) (2) When SNR 40 dBZ, ZDR and ZH have a positive correlation; (4) when ZH 40 dBZ, KDP has a strong sensitivity, and its growth rate is faster, which shows that KDP can better reflect the characteristics of heavy rainfall. Finally, three typical processes are analyzed according to the above characteristics. Compared with traditional weather radar, dual polarization radar:(1) It is more intuitive and accurate to recognize the echo type with dual polarization radar; (2) it can directly and effectively judge the hail area in the cloud; (3)The corresponding relationship between KDP and rainstorm warning level can be established. These preliminary analysis and results can better reflect the detection performance advantage and data quality of polarization radar, and have certain reference significance for the application of S-band dual polarization radar data.

Background and purpose Tanshinol borneol ester (DBZ) is a novel synthetic compound derived from Dantonic® , a botanical drug approved in 26 countries outside the United States for angina pectoris and currently undergoing FDA Phase III clinical trial. Here, we investigated the angiogenic effects of (S)-DBZ and (R)-DBZ isomers in vitro and in vivo. Experimental approach A network pharmacology approach was used to predict molecular targets of DBZ. The effects of DBZ isomers on proliferation, migration, and tube formation of human endothelial cells were assessed. For in vivo approaches, the transgenic Tg (vegfr2:GFP) zebrafish and C57BL/6 mouse Matrigel plug models were used. ELISA and western blots were used to quantitate the release and expression of relevant target molecules and signalling pathways. Key results DBZ produced a biphasic modulation on proliferation and migration of three types of human endothelial cells. Both DBZ isomers induced tube formation in Matrigel assay and a 12-day co-culture model in vitro. Moreover, DBZ promoted Matrigel neovascularization in mice and partially reversed the vascular disruption in zebrafish induced by PTK787. Mechanistically, DBZ enhanced the cellular levels of VEGF, VEGFR2, and MMP-9, as well as activating Akt and MAPK signalling in endothelial cells. Selective inhibition of PI3K and MEK significantly attenuated its angiogenic effects. Conclusions and implications These data reveal, for the first time, that DBZ promotes multiple key steps of angiogenesis, at least in part through Akt and MAPK signalling pathways, and suggest it may be potentially developed further for treating myocardial infarction and other cardiovascular diseases.

Direct peptide coupling with minimum protection strategy is a straightforward method to couple peptide segments. In order to utilize this methodology, an efficient synthetic protocol of partially protected peptides, which could show poor solubility in various solvents, was essential. Herein, we describe a new protecting group, N,N-dimethylaminoxy carbonyl (Dmaoc) and an efficient peptide coupling strategy using 3,4-diaminobenzoyl (Dbz) group as a leaving group. The Dmaoc group containing the dimethylamino group was more polar than the tBoc group, which had been utilized as one of the protecting groups for Lys-e-NH2. Intriguingly, Dmaoc was found to be removable by a reduction in the buffer containing thiol. On the other hand, we also found that the Dbz group could be used as a leaving group in the direct peptide bond formation through the formation of benzotriazol (Bt) group. The Dmaoc-protected peptide-Dbz, where the C-terminal was functionalized with Dbz, could be directly synthesized by standard protocol of Fmoc solid phase peptide synthesis. As a result, we have successfully demonstrated direct peptide coupling reactions as well as the synthesis of a small cyclic peptide. The Dmaoc/Dbz strategy would expand the chemical toolbox for the synthesis of functionalized peptides and contribute to the development of new peptide drugs.

A novel solubilizing tag system for Asp/Asn/Glu/Gln-containing peptides is described. In this method, an Asp/Glu[Dbz-Cys-NH2 ]-containing peptide (Dbz: 3,4-diaminobenzoic acid) is first synthesized through fluorenylmethyloxycarbonyl (Fmoc) solid-phase peptide synthesis. The solubilizing moiety containing an oligo-Lys group is then attached to the peptide in hexafluoroisopropanol through a trityl anchor to afford a hydrophilic tagged peptide. To detach the solubilizing tag, the Dbz moiety of the tagged peptide is activated with NaNO2 , and the Asp/Asn/Glu/Gln-containing peptide is obtained through hydrolysis or ammonolysis. This synthetic approach proved to be compatible with native chemical ligation, and amyloid β-protein 1-42 was successfully synthesized by the solubilizing-tag-aided native chemical ligation-desulfurization method.

The existence of the Doppler Blind Zone (DBZ) is one of the main challenges in the field of Doppler radar Multi-target Tracking (MTT). The situation would become more complicated when maneuvering target falls into Doppler Blind Zone. Aiming at this problem, the paper proposes a multiple maneuvering target tracking filter based on multi-model Gaussian mixture probability hypothesis density (MM-GM-PHD) in the presence of DBZ. Since DBZ only changes the detection probability of target, it is unrelated with the prediction step of MM-PHD. Therefore, we first substitute the detection probability model with minimum detectable speed (MDV) into the MM-PHD update step formula, then use the Doppler information to sequentially update intensity, and give its Gaussian mixture (GM) form implementation. Numerical analysis shows that the proposed filter can effectively track the maneuvering target in the presence of DBZ.

For ground moving target indication (GMTI) sensor tracking, the existence of the Doppler blind zone (DBZ) seriously deteriorates tracking performance. In order to minimize the adverse effects of the DBZ factor, this paper puts forward the idea of using sensor fusion technique to suppress the DBZ masking problem. First, we derive the probability hypothesis density (PHD) fusion under the generalized covariance intersection (GCI) framework and its Gaussian mixture (GM) implementation for fusing local PHDs from the local trackers. However, we find that there is the problem of cardinality underestimation (CUE) in the original PHD fusion, which is exacerbated when targets are masked by the DBZ. After analyzing this problem in detail, we propose an improved PHD fusion algorithm through operations such as scale coefficient correction, GM component partition, and fused label correction. Finally, the feasibility and effectiveness of the proposed fusion are verified through numerical examples, and it is proved that it alleviates the CUE problem and is significantly better than local trackers.

This paper considers the output tracking control of general-form single-input single-output (SISO) nonlinear system, which may encounter the problem of division by zero (DBZ). First, via the Zhang dynamics (ZD) method, a ZD controller is proposed. Then, based on the ZD controller with the aid of gradient dynamics (GD) method, a Zhang-gradient (ZG) controller is proposed. For comparison, the conventional input-output linearization (IOL) controller is presented. The ZD, ZG and IOL controllers are compared in different relative-degree cases (i.e., the standard relative-degree case, the loose relative-degree case and the DBZ relative-degree case). Note that the ZG controller is valid in three relative-degree cases, while the ZD and IOL controllers are valid only in the standard relative-degree case and the loose relative-degree case. In addition, performances of ZD and ZG controllers are guaranteed via theoretical analyses and computer simulations for the output tracking of general-form nonlinear system with the DBZ problem conquered.

An evaluation of Radar Precipitation Feature (RPF) characteristics and distribution of convective intensity is performed across 12 regions in West Africa. Results presented in this study have shown that these characteristics over West Africa revealed interesting results which were not observed on a larger spatial scale. The ice scattering characteristics and heights attained by the 15, 20, 30, and 40 dBZ echoes show patterns that agree with the season and movement of the Inter-Tropical Discontinuity (ITD). Some locations in the Western-coast rainforest, Nigeria/Cameroon rainforest and South Sudan savannah had strong potential for convective intensity during MAM, JJA, and SON as shown by their 37-GHz and 85-GHz PCT which fell below 250 K and 225 K respectively while the maximum height attained by their 20 dBZ, 30 dBZ and 40 dBZ are well above the freezing level in those locations. One result revealed a location on the eastern part of south-central Sahel (SC Sahel) where the maximum height attained by the 30 dBZ reflectivity is above 12 km and the maximum height attained by the 40 dBZ reflectivity is above 10 km during SON. The 37-GHz and 85-GHz PCT for this particular location are below 215 K and 150 K respectively indicating a very strong potential for intense convection and hence destructive storms. The distribution of convective intensity, considering only the 85-GHz PCT ice scattering signature, revealed that the percentage of convective intensity increases, especially in the rainforest and savannah, as the ITD shifts northwards during MAM, JJA and during its retreat in SON.

In this study the quality of radar rainfall with respect to temporal and spatial resolution was examined. Gwangdeoksan Radar and the Korea Institute of Civil Engineering and Building Technology (KICT) Radar were used for this purpose, along with the automatic weather systems data within Seoul. In addition, several quantitative quality measures were applied to examine the resolution. A negative bias of more than 40% in the radar rainfall of Gwangdeoksan Radar occurred with changes in the temporal and spatial resolution. However, the negative bias in the radar rainfall of KICT Radar was less than 10%. The mean square error in the radar rainfall of Gwangdeoksan Radar ranged from 5.5 to 0.4 mm2 h−2 and the mean square error in the radar rainfall of KICT Radar ranged from 30.2 to 1.5 mm2 h−2. The correlation co-efficient of the accumulated time of 30 min was more than 0.7, which increased by 30% from the correlation co-efficient of the accumulated time of 10 min. The bias in the radar rainfall of Gwangdeoksan Radar was still large with changes in the temporal and spatial resolution. However, the radar rainfall of KICT Radar was quantitatively similar to the gauge rainfall, and so the radar rainfall did not need any further quantitative correction.

This paper aims to investigate the feasibility of a Ku-band and Ka-band spaceborne/airborne dual-wavelength radar algorithm to discriminate various phase states of precipitating hydrometeors. A phase-state classification algorithm has been developed from the radar measurements of snow, mixed phase, and rain obtained from stratiform storms. The algorithm, which is presented in the form of a lookup table that links the Ku-band radar reflectivity and dual-frequency ratio to the phase states of hydrometeors, is checked by applying it to the measurements of the Jet Propulsion Laboratory, California Institute of Technology, using Airborne Precipitation Radar Second Generation (APR-2). In creating the statistically based phase lookup table, the attenuation-corrected (or true) radar reflectivity factors are employed, leading to better accuracy in determining the hydrometeor phase. In practice, however, the true radar reflectivity is not always available before the phase states of the hydrometeors are determined. Therefore, it is desirable to make use of the measured radar reflectivity in classifying the phase states. To do this, phase identification that uses only measured radar reflectivity is proposed. The procedure is then tested using APR-2 airborne radar data. The analysis of the classification results in stratiform rain indicates that the regions of snow, mixed phase, and rain derived from the phase identification algorithm coincide reasonably well with those determined from the measured radar reflectivity and linear depolarization ratio.

This paper investigates the variability of raindrop size distribution (DSD) and rain integral parameters at Ahmedabad, a tropical location, in relation to the radar estimation of rainfall. Rain DSDs for the years 2006–2007 at Ahmedabad (23°04′N, 72°38′E) have been measured using a disdrometer. Variability of DSD is evaluated for different seasons and its effect on the integral rain parameters like radar reflectivity, rainfall intensity and attenuation are examined. A percentage contribution of different drop diameters on rain integral parameters is studied to understand the seasonal behaviour of rain attenuation and radar reflectivity. It is observed that drops with diameter around 3 mm contribute maximum to the radar reflectivity while drops having a diameter around 2 mm contribute the maximum to the rainfall intensity for the present location. The critical diameter range responsible for the maximum contribution in rain attenuation found to shift towards large drops with an increase in rain rate for a fixed frequency. Linear and non-linear regression analysis between radar reflectivity and rainfall intensity show significant variations in different seasons but does not differ much for different regression techniques. Results point to the necessity of considering the seasonal variability of rain DSD in radar remote sensing and will be helpful for better characterizing of rain parameters from radar measurements.

Implementation of weather radar precipitation estimates into hydrology, especially urban hydrology practice in Poland, requires the introduction of more precise radar reflectivity versus rain rate (Z-R) relationships accounting for drop size distribution (DSD) specific for different precipitation phases. We explored the development of precipitation type dependent Z-R relationship on the basis of approximately two years of DSD recordings at high temporal resolution of ten seconds. We divided the recorded data into four separate precipitation-type groups: rain, snow, rain-with-snow, and hail. The Z-R relationships for rain and rainwith- snow showed a strong resemblance to the well-known Marshall- Palmer Z-R power-type relationship for rain. In the case of snowfall, we found that both the multiplication factor and the exponent coefficients in the Z-R formula have smaller values than for rain. In contrast, for hail precipitation these parameters are higher than for rain, especially the multiplication factor.