bluuebunny/crossref_metadata_2025 huggingface dataset:
Isolation of spirostanol glycosides from Solanum nigrum
Authors: Tai Bui Huu , Nhiem Nguyen Xuan , Van Doan Vu , Yen Pham Hai , Quang Tran Hong , Trang Do Thi , Yen Duong Thi Hai , Cuc Nguyen Thi , Van Kiem Phan
Published: February 2020

Four spirostanol glycosides, dioscin (1), asperin (2), degalactotigonin (3), and soladulcoside A (4) were isolated from the whole plants of Solanum nigrum. Their chemical structures were elucidated by analyses of their ESI‐MS, NMR spectral data, and comparison with those reported in the literature. This is the first report on the isolation of dioscin and asperin from S. nigrum.
A comparison between the use of continuous and pore network approach in the simulation of the drying process of porous media with different pore size distributions
Authors: Thai Vu Hong , Metzger Thomas , Tsotsas Evangelos
Published: February 2020

The modeling and simulation of the drying process in porous media is seen as one of the most complex and difficult problems in the numerical simulation of engineering processes. The challenge in simulating a drying process comes from the fact that all heat, mass and momentum transfers happen simultaneously and must be taken into account. The numerical simulation of the drying process in porous media can be done by using two different approaches, namely continuous and discrete approach. In the continuous approach, a continuous model is used to build a mathematical system of the porous medium undergoing drying. In this approach the material properties are averaged using the concept of averaging volume. In the discrete approach, a network of pores is considered and no averaging is needed. Each approach has its own advantages and disadvantages. In this work, we compare the use of the continuous and discrete approach in the case the information about the microstructure (pore size) of the porous medium undergoing drying is given and can be taken into account in the continuous model.
Detection of isomerization in commercial natural rubber
Authors: Thuong Nghiem Thi , Nghia Phan Trung , Kawahara Seiichi
Published: February 2020

Detection of isomerization in commercial natural rubber (NR) was performed through Nuclear Magnetic Resonance (NMR) spectroscopy in conjunction with structural analysis of pure NR. Three similar grades of commercial NR, which are technically specified rubbers from Vietnam (SVR10), India (SIR10) and Indonesia (ISNR10) and the pure NR, which is prepared by precipitation of rubber latex tapping from Hevea brasisliensis, were used in this work. All the commercial NRs were purified by acetone extraction and the pure NR were prepared by deproteinization and acetone extraction. The 13C‐NMR analysis showed that the main characteristic 13C‐signals of cis‐1,4‐isoprene unit in the polymer chain are unchanged, however, the 13C‐signal at 40 ppm, which is distinguished to the signal at 39.8 ppm, is detected for all commercial rubbers. This signal is assigned to the methyl group of trans‐1,4‐isoprene units as observed in Cariflex‐309 as a model. The appearance of this signal implied the occurrence of isomerization during processing of the commercial NR. The degradation is found to weaken the network structure and result in poor mechanical properties of commercial NR.
Synthesis and properties of some polyethers from chalcones
Authors: Linh Duong Khanh , Dai Do Ba , Vy Do Truc , Chinh Nguyen Thuy , Trung Vu Quoc
Published: February 2020

The monomers chalcones derivatives were synthesized by the condensation reactions of the 4‐hydroxy benzaldehyde and vanillin with p‐hydroxyacetophenone. The monomers were polymerized with dibromoalkanes to give the co‐polyethers containing the photocrosslinkable α, β‐unsaturated carbonyl as photosensitizer group. The structure of polyether was characterized by 1H NMR and 13C NMR spectra. The thermal stability of the polymer was measured by thermogravimetric analysis. The solubility of the polymer in the organic solvents was also studied. The polymers have to be equipped with photosensitive functional groups applied in photopolymers technology.
The effective pH‐responsive 3‐aminopropyltriethoxysilane linked with porous nanosilica for doxorubicine delivery
Authors: Vy Vo Uyen , Van Nguyen Thi Thanh , Linh Nguyen Thuy Thuy , Phan Phan Thi Kim Phuong , Nha Tran Thi Thanh , Lem Pham Hoang Ai , Khoa Nguyen Anh , Hai Nguyen Dai , Khoa Nguyen Cuu
Published: February 2020

Porous nanosilica has been identified as an outstanding candidate for controlled drug delivery. However, unmodified PNS‐based carriers usually exhibited an initial release of loaded bioactive agents, which may limit their potential clinical applications. In this study, the surface of porous nanosilica was bonded with 3‐aminopropyltriethoxysilane for Doxorubicin delivery. The modified PNS was successfully formed with spherical shape and diameter around 70 nm determined by Transmission Electron Microscopy. Drug loading and release behaviors of Doxorubicin/ Porous nanosilica‐3‐aminopropyltriethoxysilane, in particular, were also tested. This study is expected to improve the stability of PNS for drug delivery system in cancer therapy.
Synthesis, characterization and antimicrobial activity of copper doped hydroxyapatite
Authors: Nam Pham Thi , Thom Nguyen Thi , Phuong Nguyen Thu , Xuyen Nguyen Thi , Hai Nguyen Song , Anh Nguyen Tuan , Dung Pham Tien , Thanh Dinh Thi Mai
Published: February 2020

Copper hydroxyapatite coatings (CuHAp) were synthesized on 316 L stainless steel by electrodepositon and ion exchange methods. Effect of Cu2+ initial concentration and contact time to ion exchange process was investigated. The FTIR, SEM, XRD and EDX measurements of the synthesized samples showed that CuHAp coatings were single crystalline phase of HAp with %Cu of 0.08 (% mass) in Cu2+ initial solution of 0.05 M. The presence of Cu2+ reduced the HAp crystalline size and enabled to obtain samples with more uniform surface. The antimicrobial activity of CuHAp coatings was tested. CuHAp coatings had good resistance to E. coli and S. aureus that antibacterial ratio reached 89 % and 98 %, respectively.
Sesquiterpenoids from the rhizomes of Curcuma aeruginosa
Authors: Boutsada Phoutthalack , Giang Vu Huong , Linh Tran My , Mai Nguyen Chi , Cham Pham Thi , Hanh Tran Thi Hong , Phonenavong Kompheng , Sengchanh Souksakhone , Cuong Nguyen Xuan , Lien Le Quynh , Ban Ninh Khac
Published: February 2020

Six sesquiterpenoids were isolated from a methanol extract of Curcuma aeruginosa rhizomes by using various chromatographic separations. Their structures were elucidated as pyrocurzerenone (1), dehydrochromolaenin (2), curzeone (3), linderazulene (4), curzerenone (5), and 8,12‐epoxy‐1 (10),4 (15),7,11‐germacratetraen‐6‐one (6) by extensive NMR spectroscopic analysis as well as comparison with the reported data. This is the first report of isolation of compounds 1, 2, 4, and 6 from C. aeruginosa.
Effect of treatment on quality of black tiger shrimp (Penaeus monodon)
Authors: Tam Le Nhat , Xuan Uyen Phan Thuy , Anh Vu Truong Huynh
Published: February 2020

This study aimed to determine the changes in chemical, microbiological and sensory properties of black tiger shrimp (Penaeus monodon) during storage at 0°C. Two treatment preocedures were used including sodium propionate, sodium acetate. Vacuumn packaging was also investigated. Total volatile basis nitrogen (TVB‐N), trimethylamine nitrogen (TMA‐N), histamine, quality index (QI) and total viable count (TVC) were used to evaluate the quality changes of shrimp throughout storage. The results showed that the values of TVB‐N, TMA‐N, and histamine increased with storage time in two different phases, while QI value increased linearly with preservation time. The quality of shrimp decreased during storage but with different rates. The quality of shrimps treated with salts of organic acids or the sample packed in vacuum bags was significantly higher than that of the control. The shelf‐life of sample treated with 2.5 % sodium acetate orpacked in vacuum packages was 12 days, which was 4 days longer compared to the control.
New naturally occurring phenolic derivatives from marine Nocardiopsis sp. AS23C: Structural elucidation and in silico computational studies
Authors: Eliwa Essam M. , Abdel‐Razek Ahmed S. , Frese Marcel , Halawa Ahmed H. , El‐Agrody Ahmed M. , Bedair Ahmed H. , Sewald Norbert , Shaaban Mohamed
Published: February 2020

In our persistent research for new bioactive secondary metabolites from marine actinomycetes, Nocardiopsis sp. AS23C strain was isolated from the marine Alga Sargassum arnaudianum collected in the Red Sea at Hurghada coast, Egypt. A large‐scale fermentation of the strain on M2 medium containing 50% sea water, followed by fractionation and purification of the obtained extract afforded a new phenolic acid derivative, 4‐amino‐6‐methylsalicylic acid (1a), together with 5‐methylresorcinol (2) and linoleic acid (3). Their molecular structures were proved through the sophisticated spectroscopic analyses including exhaustive 1D and 2D NMR (1 and 2‐Dimensional Nuclear Magnetic Resonance) as well mass spectroscopy techniques. The extract exhibited antibacterial activity against the Gram‐positive Staphylococcus aureus, Bacillus subtilis ATCC6051, and Streptomyces viridochromogenes Tü 57. An in vitro cytotoxicity assaying of 1a and 2 against the human cervix carcinoma cell line (KB‐3‐1), pronounced no obvious activity. Additionally, in silico predictions of physicochemical properties, ADME (absorption, distribution, metabolism and excretion) parameters, acute oral toxicity and indication of toxicity targets were performed for 1a and 2 in comparison with the antioxidant agent orsellinic acid.
Withanolides from the whole plant of Physalis angulata and their anti‐inflammatory activities
Authors: Yen Pham Hai , Cuong Le Canh Viet , Dat Ton That Huu , Thuy Dinh Thi Quy , Hoa Dang Thi Ngoc , Cuc Nguyen Thi , Yen Duong Thi Hai , Thao Do Thi , Anh Hoang Le Tuan
Published: February 2020

From the dichloromethane extract of the whole plant of P. angulata growing in Vietnam, three withanolides including physagulin L (1), physagulin M (2), and withaminimin (3) were isolated by using various chromatography methods. Their chemical structures were determined by detailed analysis of 1D and 2D‐NMR data and comparison with reported data. All isolated compounds were tested for their inhibitory activities against NO production in LPS‐stimulated RAW 264.7 macrophages. The results showed that compound 3 had a weak anti‐inflammatory activity against NO production in RAW 264.7 macrophages with IC50 value of 69.6 ± 4.5 μM.
Effect of the incorporation of organoclay and melamine cyanurate on the flame retardancy and mechanical property of polyurethane foam
Authors: Nhung Hac Thi , Linh Pham Duy , Hanh Nguyen Thi , Nhan Nguyen Thanh , Oanh Ho Thi , Tuyen Nguyen Duc , Van Tuyen Nguyen , Ha Hoang Mai
Published: February 2020

The polyurethane composites were prepared by a one‐pot free‐rising method with Melamine cyanurate (MC) and Cloisite 20A additives. Flame‐retardant and mechanical properties of the foams were investigated. The vertical burning test showed that PUF composite loading 15 wt% MC was reached V0 classification of V‐rating. Limiting oxygen index (LOI) test revealed that the PU foam changed from an especially flammable material (LOI = 18.4 %) to a flame‐resistant material (LOI = 24.1 %) upon adding 25 wt% MC. However, the presence of MC reduced the compressive strength of the foam. In this report, we demonstrated the incorporation of organoclay and MC into PUF could improve the flame retardancy and the compressive strength of polyurethane foam.
Synthesis of platinum/reduced graphene oxide composite for cathode in dye‐sensitized solar cells
Authors: Thinh Nguyen Duc , Le Vo An , Nghia Le Tran Trung , Cuong Le Van , My Nguyen Thi Tra , Tuyet Nguyen Thi Kim , Hoang Nguyen Thai , Hieu Nguyen Huu
Published: February 2020

Platinum/reduced graphene oxide (Pt/rGO) composite materials with different mass ratios were fabricated by thermal decomposition method from H2PtCl6 and reduce graphene oxide (rGO) as precursors. Pt/rGO composites were used to fabricate Pt/rGO thin film cathodes by using the screen printing technology. The electrochemical properties of the fabricated cathodes were measured using the cyclic voltammetry method. Dye‐sensitized solar cells (DSSCs) were assembled from fabricated cathodes and were measured the performances by current density‐voltage (J‐V) curves and electrochemical impedance spectroscopy (EIS). The results showed the appropriate replacement amount rGO with Pt was 40 %, with the efficiency of 4.73 %, which was higher than that of commercial Pt cathode. The characterizations of the appropriate Pt/rGO composite were investigated by Fourier‐transform infrared spectroscopy (FTIR) and Raman spectroscopy. X‐ray diffraction (XRD) patterns indicated that the interlayer distance between the rGO was 0.35 nm while the transmission electron microscopy (TEM) image showed the Pt nanoparticles with size of 10‐20 nm were evenly distributed on the rGO sheets. These results indicated that Pt/rGO could be appropriated material to replace Pt in DSSCs to reduce the produce cost and enhance the efficiency.
Study on polarization of antimony lead electrode in gelled electrolyte
Authors: Binh Phan Thi , Van Anh Nguyen Thi , Thuy Mai Thi Thanh , Xuan Mai Thi
Published: February 2020

Gelled electrolyte is prepared from liquid glass and sulfuric acid with various specific weights in the presence of both gelling agents such as polyacrylamide and polyaniline. The antimony lead electrode is polarized by potentiodynamic method in gelled electrolyte compared with sulfuric acid solution (1.26 g/cm3). The results found that not only the overpotential of gas evolution but also the polarization resistance depends on sample preparation conditions. The concentration of PAM at 0.55 wt% contributed to the shift of overpotential of oxygen release in the more positive side but made decreasing the hydrogen escape overpotential compared with H2SO4 solution (1.26 g/cm3). It showed that the presence of PANi together with PAM did not improve the overpotential of oxygen release, but significantly inhibited the hydrogen evolution, although polarization resistance was approximately or smaller than that in H2SO4 solution (1.26 g/cm3).
In‐vitro DNA binding and antimicrobial studies of trivalent transition metal ion based macrocyclic complexes
Authors: Sangwan Vikas , Singh D. P.
Published: February 2020

In the current research work diaminotoluene based tetra‐azamacrocyclic‐14 membered [N4] macrocylic complexes of nitrate, chloride and acetate trivalent transition metals salts of Cr(III) and Fe(III) have been synthesized by taking the route of template methodology. The synthesized complexes were fully characterized by spectroscopic and physico‐analytical techniques like IR, ESI‐MS, ESR, Powder XRD, TGA, UV‐visible, magnetic moment, molar conductance, in addition to the elemental analysis measurements. The monomeric and electrolytic nature of the complexes is elucidated by the help of ESI‐MS and molar conductance values that reveals about the 1:2 electrolytic behaviour. On the basis of above analytical techniques the complexes may be empirically formulated as [MLX]X2 in which L is macrocyclic ligand obtained from the [2+2] condensation reaction of 3,4‐diaminotoluene (DAT) and dibenzoylmethane (DBM). The thermal data provides an indication towards the absence of water molecular and various decomposition steps in the complexes. Further the compounds were screened for their antimicrobial potency against few strains of bacteria and fungus and fair results were found from the above studies. In addition to these DNA binding activity was also performed in order to elucidate the mode of binding the newly synthesised complexes.
Antiproliferative activity of isolated compounds from Pinus dalatensis and Pinus krempfii on acute myeloid Leukemia cells
Authors: Sa Nguyen Hoang , Tam Nguyen Thanh , Quan Tran Duc , Anh Nguyen Thi Hoang , Linh Nguyen Thi Thuy , Nhung Le Thi Hong , Adorisio Sabrina , Delfino Domenico V , Van Sung Tran , Thuy Trinh Thi
Published: February 2020

Our previous chemical constituent study of Pinus dalatensis and Pinus krempfii had identified six compounds 1‐6. The continuing investigation of biological activity of the conifer species led to discovery of the antiproliferative activity of all isolated compounds 1‐6 on acute myeloid leukemia cells as shown by the effects on cell cycle progression. Remarkably, compound 3 (chrysin) exibited potent bioactivity at the concentration of 10 μg/mL.
Molecular dynamics simulation of the interaction between human CD38 and some quinoline derivative inhibitors using reactive force field
Authors: Van Dang Ung
Published: February 2020

The paper presented initial calculated results obtained by molecular dynamics simulations of some CD38‐ micro and nanomolar inhibitor systems in vacuum using reactive force field ReaxFF. The ReaxFF software integrated in SCM's ADF has been used. The analysis and processing of results has been supplemented by VMD, CHIMERA and some external support softwares. The initial results showed that there are some associations between the inhibitor activity and the parameters compared apo and complex configurations. In particular, the higher the activity, the greater the difference in protein backbone RMSD between apo and complex. Nanomolar inhibitor molecules approached closer to the AC1 active site residues, especially GLU146 than micromolar one. In addition, the averaged and maximum fluctuation value of residues is also proportional to inhibitory activity. These can be considered suggestions for continuing to clarify the mechanism of CD38 inhibition of different ligand types supporting to the prediction and recommendation of new high active inhibitors
Modification of the vinylogous aldol condensation – Another approach to the synthesis of C(15)‐alkylidene and benzylidene andrographolide derivatives
Authors: Huy Ly Minh , Dung Huynh Ha Ngoc , Hy Nguyen Dinh , Trang Le Bao , Kien Duong Trung , Nghiem Tieu Uy , Van Anh Tran Thi , Tuyen Truong Ngoc
Published: February 2020

A two‐step protocol for the synthesis of 15‐alkylidene and benzylidene derivatives of 14‐deoxy‐11,12‐didehydroandrographolide, which was conducted through a dehydration reaction of andrographolide and a vinylogous aldol condensation between α,β‐unsaturated butenolide moiety and benzaldehyde derivatives has been developed. Combining with various experiments on new catalysts for these reactions: the dehydration of andrographolide by concentrated H2SO4 and the vinylogous aldol reaction by K2CO3 in MeOH or a mixture of CH3COOH/pyrrolidine in MeOH, this research has determined the optimized conditions for those catalysts and the new approach to this aldol‐like reaction. All compounds synthesized were characterized by the analysis of IR, NMR, HRMS spectra.
Bioactive compounds from marine Streptomyces sp.: Structure identification and biological activities
Authors: Abd‐Ellatif Aya E. S. , Abdel‐Razek Ahmed S. , Hamed Abdelaaty , Soltan Maha M , Soliman Hesham S. M. , Shaaban Mohamed
Published: February 2020

The marine Iotrochoto purpurea derived Streptomyces sp. IOPU produced ten diverse bioactive compounds: hexahydro‐menaquinone MK‐9 (1), borrelidin (2), ferulic acid (3), N‐acetylanthranilic acid (4), uracil (5), uridine (6), thymidine (7), sitosteryl‐3β‐D‐glucoside, linoleic acid and methyl linoleate. Structures of the obtained compounds were assigned by NMR and mass spectrometric means. The cytotoxic and antimicrobial activities of the extract were visualized against KB‐3‐1 and KB‐V1 cell lines, and a set of microorganisms. Borrelidin (2), was the potentially active against the colorectal Caco‐2 and breast MCF‐7 subtypes, with IC50 5.3 μM and < 3.1 μM, respectively. The obtained compounds were investigated as antioxidant and antimicrobial agents.
Investigation of effect of polyethylene oxide on properties and morphology of polylactic acid/chitosan/quinine composites
Authors: Trang Nguyen Thi Thu , Chinh Nguyen Thuy , Mai Tran Thi , Trung Tran Huu , Hoang Thai
Published: February 2020

Polylactic acid (PLA) and chitosan (CS) has been attracted by many researchers due to their good
adhesion, biodegradability and biocompatibility. Quinine has been used for the treatment of malaria. In this work, we used emulsion method to prepare polylactic acid/chitosan/quinine (PCQ) nanoparticles with polyethylene oxide (PEO) as a compatibilizer and emulsifier. The content of containing PEO was 3‐10 wt. % compared with the weight of PLA. These nanocomposites were characterized by Fourier transform infrared spectroscopy (FTIR), Differential scanning calorimetry (DSC), and field emission scanning electron microscopy (FESEM). The FTIR spectra of these nanoparticles show that PLA, CS and quinine are interact through the hydrogen bonding and dipolar‐dipolar interactions between C‐O, C=N, OH groups in quinine and C‐O, NH, OH groups in chitosan with C‐O, C=O, OH groups in PLA. The FESEM images of the nanoparticles with different PEO contents indicate that the nanoparticles have a spherical shape with the average particle size in the range of 80‐220 nm.
Effects of processing conditions on properties and morphology of chitosan/lovastatin particles
Authors: Thang Dam Xuan , Chinh Nguyen Thuy , Ngoc Dinh Hong , Tung Nguyen Quang , Hoang Thai
Published: February 2020

This paper presents the effect of processing conditions on properties and morphology of chitosan particles loading lovastatin as a model drug. The processing conditions were investigated here including solvents for dissolution of drug, emulsifier content and temperature of drying process. Two solvents chosen to dissolve lovastatin were ethanol and dichloromethane. Polyethylene oxide used as an emulsifier with different contents for preparation of chitosan/lovastatin particles. Two methods for evaporation of water in the samples were freeze‐drying and natural air drying in convection oven. The characteristic properties and morphology of chitosan/lovastatin particles were observed, determined and evaluated by Fourier transform infrared spectra, size distribution, and scanning emission microscopy images. From the above data and images, we can find the most suitable condition for the preparation of chitosan/lovastatin particles.
Synthesis of new 1,2,3‐triazole derivatives from vanillin and β‐naphthol
Authors: Tai Thai Duy Phuoc , Ngoan Le Hoang , Thanh Le Thanh , Duy Vo Duc , Thanh Le Tin
Published: February 2020

We herein report the synthesis of two new 1,2,3‐triazole derivatives from vanillin and β‐naphthol. These 1,2,3‐triazoles contain the diaryl ether moiety which has been synthesized via SNAr reaction under mild conditions and in excellent yields. Chemical structures of these triazoles were elucidated by spectroscopic analyses (HR‐MS, NMR, IR).
A new iridoid from leaves of Avicennia officinalis L.
Authors: Thu Nguyen Thi Hoai , Hoang Tran , Vinh Nguyen Hoang Tien , Phung Nguyen Kim Phi
Published: February 2020

Avicennia officinalis L., Avicenniaceae,is a widespread plant in mangrove forests in Vietnam, Cambodia, Thailand, Indonesia,… A. officinalis’s chemical compositions remain mostly unknown. Therefore, we now report on the structural elucidation of six compounds isolated from this plant growing in Can Gio mangrove forest in Ho Chi Minh City by using a variety of chromatographic techniques. The structures of these compounds were elucidated by NMR spectroscopy analysis as well as compared with data in the literature. They areaviridoid(1), (1S,5R,8S,9R)‐2'‐(E‐coumaroyl)mussaenosidic acid (2), velutin (3), α‐tocopherol (4), and a mixture of 6‐methoxynaphtho[2,3‐b]‐furan‐4,9‐quinone (5) and 7‐methoxynaphtho[2,3‐b]‐furan‐4,9‐quinone (6). To the best of our knowledge, (1) is a new compound while (2), (4), (5) and (6) are obtained from Avicennia genus for the first time. Further studies on this species are in progress.
Preparation and properties of rubber nanocomposites based on NR/NBR blend reinforced with nanosilica and carbon black
Authors: Hiep Ngo Quang , Huy Tran Huu , Nguyen Pham Cong , Sy Do Trung , Khang Do Quang
Published: February 2020

Rubber nanocomposites based on natural rubber (NR)‐butadiene nitrile rubber (NBR) blend filled with silane modified nanosilica (NSBT) and carbon black (CB) were prepared by melt mixing method by using an internal mixer. The effect of CB and NSBT on thermo‐mechanical properties of the materials was investigated by scanning electron microscopy (SEM), thermogravimetric analysis (TGA), dynamic‐mechanical analysis (DMA) and tensile testing method. The results show that the NR/NBR blends reinforced with both CB and NSBT possess the properties much better than that reinforced with only CB or NSBT. With the CB/NSBT ratio of 25/5, the properties of the NR/NBR blends were remarkably enhanced, especially the increase in tensile strength by about 64 % and the increase in the thermal stability by about 13°C. The reasons for the improvement of NR/NBR blends’ properties are due to better compatibility of the components in the rubber blend as well as the better compactness in their structure with the presence of NSBT.
Simulation of summer precipitation diurnal cycles over the Tibetan Plateau at the gray-zone grid spacing for cumulus parameterization
Authors: Ou Tinghai , Chen Deliang , Chen Xingchao , Lin Changgui , Yang Kun , Lai Hui-Wen , Zhang Fuqing
Published: February 2020

The Tibetan Plateau (TP) is often referred to as the “water tower of Asia” or the “Third Pole”. It remains a challenge for most global and regional models to realistically simulate precipitation, especially its diurnal cycles, over the TP. This study focuses on evaluating the summer (June–August) precipitation diurnal cycles over the TP simulated by the Weather Research and Forecasting (WRF) model. The horizontal resolution used in this study is 9 km, which is within the gray-zone grid spacing that a cumulus parameterization scheme (CU) may or may not be used. We conducted WRF simulations with different cumulus schemes (CU experiments) and a simulation without CU (No_CU experiment). The selected CUs include the Grell-3D Ensemble (Grell), New Simplified Arakawa-Schubert (NSAS), and Multiscale Kain-Fritsch (MSKF). These simulations are compared with both the in-situ observations and satellite products. Results show that the scale-aware MSKF outperforms the other CUs in simulating precipitation in terms of both the mean intensity and diurnal cycles. In addition, the peak time of precipitation intensity is better captured by all the CU experiments than by the No_CU experiment. However, all the CU experiments tend to overestimate the mean precipitation and simulate an earlier peak of precipitation frequency when compared to observations. The frequencies and initiation timings for short-duration (1–3 h) and long-duration (> 6 h) precipitation events are well captured by the No_CU experiment, while these features are poorly reproduced by the CU experiments. The results demonstrate simulation without a CU outperforms those with a CU at the gray-zone spatial resolution in regard to the precipitation diurnal cycles.
Ultrastructure and cytochemistry of intrauterine embryonic and larval stages of Ityogonimus lorum (Digenea: Brachylaimidae) involving transitory development of ciliated miracidia
Authors: Świderski Zdzisław , Conn David Bruce , Miquel Jordi
Published: February 2020

Results of the present study provide ultrastructural evidence that miracidial morphogenesis is fully completed within the intrauterine eggs while in the most posterior uterine regions of Ityogonimus lorum, a digenean parasite of an Iberian mole, Talpa occidentalis (Eulipotyphla, Talpidae). Using transmission electron microscopy (TEM), the ultrastructural characteristics of diverse cell types and their organelles of these developing embryos and fully formed miracidia within the eggshell were examined. The eggshell and embryonic envelopes are similar to those described previously by many authors for other digeneans. However, the developing miracidia are unique among previously described digeneans in possessing transitory cilia during larvigenesis, but completely lacking cilia in fully formed miracidium larvae. The evidence for completion of miracidial maturation in intrauterine eggs is based on the presence of the following structures: (1) transitional stage of ciliated differentiating miracidial epithelium; (2) apical and lateral glands, characteristic for digenean miracidia; and (3) fully developed germinative cells grouped together in the germinative sac localized in the posterior region of the miracidium. The protonephridial system with its characteristic flame cells and the nervous system with diverse types of neurons and nerve centers, which are characteristic for other digenean species reported until now, are absent from all these developmental stages of I. lorum. Based on these observations, we hypothesize that the life cycle of I. lorum is entirely terrestrial, involving passive transmission by ingestion of eggs containing unciliated miracidia to the first intermediate host.
Effectiveness of current psychological interventions to improve emotion regulation in youth: a meta-analysis
Authors: Moltrecht Bettina , Deighton Jessica , Patalay Praveetha , Edbrooke-Childs Julian
Published: February 2020

Background

Research investigating the role of emotion regulation (ER) in the development and treatment of psychopathology has increased in recent years. Evidence suggests that an increased focus on ER in treatment can improve existing interventions. Most ER research has neglected young people, therefore the present meta-analysis summarizes the evidence for existing psychosocial intervention and their effectiveness to improve ER in youth. A systematic review and meta-analysis was conducted according to the PRISMA guidelines. Twenty-one randomized-control-trials (RCTs) assessed changes in ER following a psychological intervention in youth exhibiting various psychopathological symptoms. We found moderate effect sizes for current interventions to decrease emotion dysregulation in youth (g = − 0.46) and small effect sizes to improve emotion regulation (g = 0.36). Significant differences between studies including intervention components, ER measures and populations studied resulted in large heterogeneity. This is the first meta-analysis that summarizes the effectiveness for existing interventions to improve ER in youth. The results suggest that interventions can enhance ER in youth, and that these improvements correlate with improvements in psychopathology. More RCTs including larger sample sizes, different age groups and psychopathologies are needed to increase our understanding of what works for who and when.
The impact of neighborhood services on land values: an estimation through the hedonic pricing model
Authors: Aziz Asad , Anwar Muhammad Mushahid , Dawood Muhammad
Published: February 2020

A strong need exists to increase the knowledge and recognize the values of neighborhood services. This paper makes an attempt to examine the impact of neighborhood services on land values, through analysis based on results obtained from multi linear regression analysis. This case study was done in area of dense urban settlement to check the consequence of neighborhood services through the hedonic pricing model base variables which include the structural, locational, community and neighborhood services. The regression coefficient was checked at (p < 0.05) level of significance for each variable. The primary data was collect through the questionnaire filling by random sampling and Punjab Urban Gazette was used for the verification of land values in study area. The results found a valuable potential on land and property values of neighborhood services through the regression analysis results express through R (0.926), R2 (0.856) and coefficient tables to represent the effect of each individual variable on property and land values. Every individual variable play role in defining the values of land and property based upon its utilization such as larger the structure of a property, more the covered area, larger size of a property more the land area higher price. Similarly, for locational factor study in geography, a piece of land adjacent to the road have high land values 50–70% compare to those located at distance. Very less attention has been paid on such issues in the world due to lack of effective urban planning and research on such crucial issues. If empirical studies on such issue has been done, effective way can be obtained for urban planning.
Creating a Validated Simulation Training Curriculum in Otolaryngology
Authors: Bhalla Sanjana , Tolley Neil , Awad Zaid
Published: February 2020

Purpose of Review

Simulation-based training is an integral component of surgical training. It allows practice of technical skills within a safe environment without compromising patient safety. This article seeks to review current virtual and non-virtual reality simulation models within the literature and review their validation status.

Recent Findings

Many simulation models exist within otolaryngology and are currently being used for education. New models are also continuously being developed; however, validity should be proven for the models before incorporating their use for educational purposes. Validity should be determined by experts and trainees themselves.

A validated simulation curriculum should be incorporated within the otolaryngology training programme. A curriculum based on the current training programme at our institution serves as an exemplar for local adoption.
Modification of Silicon Microsegregation in Solid-Solution-Strengthened Ductile Iron by Alloying with Aluminum
Authors: Franzen D. , Weiß P. , Pustal B. , Bührig-Polaczek A.
Published: February 2020

In solid-solution-strengthened ferritic ductile iron (SSFDI), a silicon content above 4.3 wt% leads to an abrupt decrease in ultimate tensile strength and elongation at fracture. This phenomenon has recently been proven to be attributed to the formation of iron–silicon long-range orderings that lead to an embrittlement of the material. It is assumed that the local tendency to form silicon superstructures is promoted in particular by the occurrence of silicon microsegregation. During solidification of ductile iron, silicon segregates inversely into the austenite. Thus, the highest silicon concentration is larger than the initial concentration of the melt and is located directly at the graphite nodules. As a straight consequence, the presence of silicon superstructures is expected primarily in these areas. Therefore, the focus is on homogenization of the silicon microsegregation profile in order to avoid the formation of brittle iron–silicon superstructures. For this purpose, in the present study the alloying concept of SSFDI is adapted. Thermodynamic–kinetic simulations as well as experimental investigations indicate that aluminum concentrations of approx. 1.2 wt% lead to an inversion of the silicon microsegregation. The findings provide a promising tool to shift the silicon embrittlement in SSFDI to higher silicon concentrations. This method could be used to increase the maximum strength, to improve toughness properties or to increase the process integrity against deviations in silicon content.
Exploring Hidden Local Ordering in Microemulsions with a Weak Directive Second Order Parameter
Authors: Kerscher Michael , Lipfert Frederik , Frielinghaus Henrich
Published: February 2020

So far, the near-surface ordering of microemulsions was focused on lamellar ordering while the bulk microemulsion was bicontinuous. In a series of different non-ionic surfactants the near-surface ordering of microemulsions at a hydrophilic silicon surface was studied using grazing incidence small angle neutron scattering. For the surfactant C8E3, most likely a gyroid structure was found at the solid–liquid interface, while the more efficient surfactants find lamellar ordering up to lamellar capillary condensation. The ranges for near-surface ordering are deeper than the bulk correlation lengths. These findings point towards theories that use directional order parameters that would lead to deeper near-surface ordering than simple theories with a single scalar order parameter would predict. Rheology experiments display high viscosities at very low shear rates and, therefore, support the existence of a directional order parameter.
Ploughing-Pulling Forming for Wicking Structure of Flat Micro-Groove Heat Pipe and Machine Tool Optimization
Authors: Li Xibing , Ye Zhixiong , Li Nanpeng , Chen Jialun , Zou Tengyue
Published: February 2020

In forming procedure of the micro grooves in the flat micro-groove heat pipe, the tie rod is often observed to be broken and the multi-tooth cutter is damaged due to the sharp increase of the ploughing-pulling pressure. This paper theoretically analyzes the factors affecting the capillary heat transferring limit of the micro-groove heat pipe, and simulates the machining process using finite element to acquire the best processing parameters: the squeeze angle is 120°, the drawing depth is 0.25mm, and the ploughing-pulling velocity is 100mm/s. Then these parameters are verified by real manufacturing experiments. The experimental results show that the ploughing-pulling pressure of the micro-groove forming process is close to the strength limit of the rod or multi-tooth cutter, and the process makes little swarf during work. Thus, only using the appropriate machine tool parameters, forming parameters and forming methods can make the wicking structure of flat micro-groove micro-heat pipe with the best heat transferring performance.
Nematocidal effect of Piper retrofractum Vahl on morphology and ultrastructure of Strongyloides stercoralis third-stage infective larvae
Authors: Riyong D. , Sangkhantree C. , Champakaew D. , Jitpakdi A. , Tippawangkosol P. , Junkum A. , Chaithong U. , Wannasan A. , Yasanya T. , Somboon P. , Pitasawat B.
Published: February 2020

In a previous research work aimed at discovering natural helminthicides as alternatives to conventional synthetic drugs, Piper retrofractum fruit hexane extract (PHE) has been shown to possess promising nematocidal activity against the third-stage infective larvae of Strongyloides stercoralis. Thus, this study was designed to evaluate the chemical composition and the impact of PHE on symptom and structural alterations of S. stercoralis. Chemical analysis of PHE by gas chromatography–mass spectrometry demonstrated 26 different compounds, constituting 100% of the total composition. The main components were 4-acetylphenyl (4-benzoylphenoxy) acetate (14.86%) and octyl methoxycinnamate (12.72%). Nematocidal bioassays revealed promising potential of PHE against S. stercoralis larvae, with an LC50 value of 0.059 mg/ml, while the reference drug ivermectin exerted higher efficacy, with an LC50 value of 0.020 µg/ml. Behavioural observations under light microscopy revealed that PHE-treated S. stercoralis larvae moved slowly, became paralysed and eventually died during 24 h of incubation. The dead larvae appeared under light microscope as straight worms with unknown vacuoles of different sizes inside their internal bodies. Morphological alterations of the PHE-treated S. stercoralis larvae, such as straight bodies with swollen cuticle, faded transverse annulations and faded longitudinal striations, as well as shallow and smooth lateral longitudinal grooves, were seen clearly under scanning electron microscopy. Ultrastructural changes in the treated larvae, such as protruded lateral longitudinal grooves, loose muscle with vacuolation, dissociation between the hypodermis and cuticle and marked intracellular disorganization with vacuolation, were detected under transmission electron microscopy. The results of this study provide evidence that PHE is toxic against S. stercoralis and also a potential new alternative for anti-Strongyloides chemotherapy.
Human occupation, impacts and environmental management of Bunger Hills
Authors: Gore Damian B. , Gibson John A.E. , Leishman Michelle R.
Published: February 2020

The types and distributions of anthropogenic rubbish have been documented at Bunger Hills, East Antarctica. The area has been the site of scientific research stations from 1958 to the present. Rubbish types include deliberately or negligently discarded items (gas cylinders, broken glass), abandoned unserviceable equipment (boats, vehicles, scientific equipment), spills (chemicals, fuel, oil) and the slow collapse of old buildings. Some rubbish remained where it was left, while other material was redistributed by strong winds. Modern expeditioner training should limit the production of new rubbish, while inadvertent wind dispersal of rubbish from old station buildings could be minimized by better management of these structures and their surrounds. Buildings and other constructed items need ongoing maintenance if they are not to break down and be distributed by wind, or they should be removed within a reasonable period.
Reanastomosis and rehabilitation of interrupted left pulmonary artery derived from atretic ductus
Authors: Schiff Andrew F. , Williams Derek A. , Ootaki Yoshio
Published: February 2020

True absence of a branch pulmonary artery is rare. We identified a patient initially diagnosed with an absent left pulmonary artery at a previous hospital. Due to disagreement in the initial diagnosis, she had a diagnostic catheterisation, which revealed an isolated left pulmonary artery off the left innominate artery via a ductus. The ductus was recanalised with serial stenting and balloon dilatation followed by reanastomosis to the main pulmonary artery. In a patient who initially is diagnosed with an absent pulmonary artery, an alternative diagnosis, such as this case report, should be considered.
SPHERICALIZATION AND FLATTENING PRESERVE UNIFORM DOMAINS IN NONLOCALLY COMPACT METRIC SPACES
Authors: LI YAXIANG , PONNUSAMY SAMINATHAN , ZHOU QINGSHAN
Published: February 2020

The main aim of this paper is to investigate the invariant properties of uniform domains under flattening and sphericalization in nonlocally compact complete metric spaces. Moreover, we show that quasi-Möbius maps preserve uniform domains in nonlocally compact spaces as well.
A Comprehensive Horizon‐Picking Method on Subbottom Profiles by Combining Envelope, Phase Attributes, and Texture Analysis
Authors: Zhao Jianhu , Li Shaobo , Zhao Xi , Feng Jie
Published: February 2020

We propose a new method that considers the envelope, phase attributes, and texture analysis of the subbottom profile to automatically obtain continuous and accurate horizon picking. This method overcomes the shortcomings of the traditional methods in envelope and phase automatic horizon picking in terms of accuracy and continuity, and in efficiency when it comes to manual picking. Under the constraint of the envelope threshold from the envelope image and the texture segmentation from the phase image, the accurate envelope horizons are picked from the envelope image. Through mean filtering and template enhancement, the fine phase horizons are picked from the phase image. Finally, by combining the two kinds of picked horizons, more continuous, accurate, and finer horizons are obtained. The proposed method was tested on a real data set.
Radiocarbon Evidence for the Contribution of the Southern Indian Ocean to the Evolution of Atmospheric CO2 Over the Last 32,000 Years
Authors: Ronge Thomas A. , Prange Matthias , Mollenhauer Gesine , Ellinghausen Maret , Kuhn Gerhard , Tiedemann Ralf
Published: February 2020

It is widely assumed that the ventilation of the Southern Ocean played a crucial role in driving glacial‐interglacial atmospheric CO2 levels. So far, however, ventilation records from the Indian sector of the Southern Ocean are widely missing. Here we present reconstructions of water residence times (depicted as ΔΔ14C and Δδ13C) for the last 32,000 years on sediment records from the Kerguelen Plateau and the Conrad Rise (~570‐ to 2,500‐m water depth), along with simulated changes in ocean stratification from a transient climate model experiment. Our data indicate that Circumpolar Deep Waters in the Indian Ocean were part of the glacial carbon pool. At our sites, close to or bathed by upwelling deep waters, we find two pulses of decreasing ΔΔ14C and δ13C values (~21–17 ka; ~15–12 ka). Both transient pulses precede a similar pattern in downstream intermediate waters in the tropical Indian Ocean as well as rising atmospheric CO2 values. These findings suggest that 14C‐depleted, CO2‐rich Circumpolar Deep Water from the Indian Ocean contributed to the rise in atmospheric CO2 during Heinrich Stadial 1 and also the Younger Dryas and that the southern Indian Ocean acted as a gateway for sequestered carbon to the atmosphere and tropical intermediate waters.
Foldable All‐Textile Cavity‐Backed Slot Antennas for Personal UWB Localization
Authors: Van Baelen Dries , Van den Brande Quinten , Lemey Sam , Verhaevert Jo , Rogier Hendrik
Published: February 2020

An all‐textile multimoded cavity‐backed slot antenna has been designed and fabricated for body‐worn impulse radio ultra‐wideband (IR‐UWB) operation in the 3,744–4,742.4 MHz frequency band, thereby covering Channels 2 and 3 of the IEEE 802.15.4a standard. Its light weight, mechanical flexibility, and small footprint of 35 mm 
 56 mm facilitate integration into textile for radio communication equipment for first aid responders, personal locator beacons, and equipment for localization and medical monitoring of children or the elderly. The antenna features a stable radiation pattern and reflection coefficient in diverse operating conditions such as in free space, when subject to diverse bending radii and when deployed on the torso or upper right arm of a test person. The high isolation toward the wearer's body originates from the antenna's hemispherical radiation pattern with a
3 dB beamwidth of
and a front‐to‐back ratio higher than 11 dB over the entire band. Moreover, the antenna exhibits a measured maximum gain higher than 6.3 dBi and a radiation efficiency over
%. In addition, orientation‐specific pulse distortion introduced by the antenna element is analyzed by means of the System Fidelity Factor (SFF). The SFF of the communication link between two instances of this antenna is higher than 94% for all directions within the antenna's
3 dB beamwidth. This easily wearable and deployable antenna is suitable to support IR‐UWB localization with an accuracy in the order of 5 cm.
Stream and Spring Water Evolution in a Rapidly Urbanizing Watershed, Austin, TX
Authors: Beal Lakin , Senison Jeffrey , Banner Jay , Musgrove MaryLynn , Yazbek Lindsey , Bendik Nathan , Herrington Christopher , Reyes Daniel
Published: February 2020

Quantifying urban development impacts on fresh water quality and quantity is critical, especially as growing populations concentrate in urban centers and with climate change projections of increased hydrologic extremes. We investigate geochemical processes through which municipal supply and waste water, carbonate bedrock, and soils impact stream and spring water compositions within the Bull Creek watershed (Austin, Texas). This watershed exhibits a sharp geographic divide between urban and rural land. Urban and rural waters were assessed to quantify relative influences of municipal water on stream and spring water elemental compositions and 87Sr/86Sr values. Higher 87Sr/86Sr for samples from urban sites relative to rural sites can be accounted for by two processes: (1) water leakage from municipal infrastructure and/or irrigation or (2) ion exchange as precipitation infiltrates through soils with varying 87Sr/86Sr. Irrigated soils have higher 87Sr/86Sr than unirrigated soils, indicating that irrigated municipal water resets soil compositions and that process (1) is a dominant driver of urban stream and spring water evolution. Geochemical modeling results indicate that urban waters consist of 50% to 95% municipal water. Geochemical modeling further demonstrates the evolution of municipal water as it infiltrates as groundwater and undergoes water‐rock interaction. These results are compared with groundwater compositions on a regional scale to infer local flow paths and relative groundwater residences times of municipal water. This study provides a geochemical modeling framework that quantifies both the significance of municipal water on urban stream water and soil compositions and the role of municipal water within urbanized watersheds and aquifers.