bluuebunny/crossref_metadata_2025_split huggingface dataset:
Research on Improving Seals to Suppress Vibration of Rotary Machines
Authors: Lu Congxiang , Shevchenko Serhii , Geichuk Volodymyr , Korchak Mykola , Topalov Andrii 
Published: June 2024

There is a constant demand for higher equipment parameters, such as pressure of a sealing medium and shaft rotation speed. However, as the parameters rise it becomes more difficult to ensure hermetization efficiency. Moreover, sealing systems affect the overall operational safety of the equipment, especially vibratory. Non-contact seals are considered hydrostatodynamic supports that can effectively damp rotor oscillations. Models of an impulse and a groove seals, models of rotor-seals system and rotor-auto-unloading system, models of a shaftless pump are studied to evaluate the effect of these sealing systems on oscillatory characteristics of rotor. Analytical dependencies for computation the dynamic characteristics of impulse seals, hydromechanical systems rotor-seals and rotor-auto-unloading, as well as shaftless pumps are obtained. These dependencies describe the radial-angular vibrations of a centrifugal machine rotor in seals-supports. Equations for computation the amplitude-frequency characteristics are given. The directions of improving the environmental safety of critical pumping equipment by purposefully increasing the rigidity of non-contact seals that leads to higher rotor vibration stability have been determined.
Diagnostic Value of Point Shear Wave Elastography (pSWE) of the Spleen for Assessment of Liver Fibrosis in Patients with Chronic Viral Hepatitis
Authors: Doykova Katia , Doykov Daniel , Tsvetkova Silvia , Andonov Vladimir 
Published: June 2024

In recent years spleen stiffness (SS), assessed by point shear wave elastography (pSWE) has been a topic of interest as a more accurate indicator for the diagnosis of liver fibrosis in chronic viral hepatitis. For the first time in Bulgaria, a comprehensive research on the stiffness of the liver and spleen has been performed by pSWE in patients with chronic viral hepatitis, as well as evaluation of their correlation with the histological assessment of liver fibrosis. The aim of the research is to establish spleen and liver stiffness in patients with chronic viral hepatitis and their correlation with intermediate stages of liver fibrosis diagnosed histologically after biopsy. For the period 2018–2020, ninety patients with chronic viral hepatitis B and C (mean age 46.20±14.55) from the department of Gastroenterology, University hospital Kaspela, Plovdiv, Bulgaria, have been examined, by abdominal ultrasound, pSWE of the liver and spleen, histological evaluation of liver fibrosis, data study on the presence of esophageal varices and ascites. The liver stiffness (LS) value distinguishing between F1 and F2 was 1.86 m/s (rs=0.769, 95% CI: 0.652–0.850, p<0.001). The spleen stiffness (SS) value distinguishing between F1 and F2 was 2.95 m/s (rs=0.838, 95% CI: 0.749–0.898, p<0.001). Liver stiffness is significantly affected by BMI, which reduces its diagnostic potential in obese patients. Spleen stiffness measured by pSWE can be used in the diagnosis of intermediate stages of liver fibrosis in patients with chronic hepatitis B and C.
A Multifunction Heterojunction Formed Between Pentacene and a Single‐Crystal Silicon Nanomembrane
Authors: Seo Jung‐Hun , Oh Tae‐Yeon , Park Jungho , Zhou Weidong , Ju Byeong‐Kwon , Ma Zhenqiang 
Published: February 2013

AbstractA mesh patterned n‐type single‐crystalline silicon nanomembrane (SiNM) created from a silicon‐on‐insulator (SOI) wafer is complementally combined with a p‐type pentacene layer to form a heterogeneous p‐n junction on a flexible plastic substrate. Excellent rectifying characteristics are obtained from the heterogeneous p‐n diode. The diode also exhibits photosensitivity at visible wavelengths with a photo‐to‐dark current ratio exceeding four orders, a responsivity of 0.7 A/W, and an external quantum efficiency of 21.9% at 633 nm. Over 60% average transmittance in the visible spectrum is measured from the heterogeneous multilayer junction on a plastic substrate. Outstanding mechanical bending characteristics are observed with up to 1.08% of strain applied to the diode. These results suggest that organic‐inorganic heterogeneous integration may be a viable strategy to build flexible organic‐inorganic heterojunction devices and thus enable a number of novel multifunctional applications.
Self‐Supporting Graphene Hydrogel Film as an Experimental Platform to Evaluate the Potential of Graphene for Bone Regeneration
Authors: Lu Jiayu , He Yu‐Shi , Cheng Chi , Wang Yi , Qiu Ling , Li Dan , Zou Derong 
Published: February 2013

AbstractGraphene, a two dimensional carbonaceous material possessing a range of extraordinary properties, is considered promising for biomedical applications. Here, a simple form of graphene‐based bulk material–self‐supporting graphene hydrogel (SGH) film is used as a suitable platform to study the intrinsic properties of graphene both in vitro and in vivo. The free‐standing film show good cell adhesion, spreading, and proliferation. Films are implanted into subcutaneous sites of rats, and produce minimal fibrous capsule formation, and mild host tissue response in vivo. New blood vessel formation is also seen. The films swell and cracked in vivo, indicating the beginning of degradation. Of particular interest is that the film alone is found to be able to stimulate osteogenic differentiation of stem cells, without additional inducer, both in vitro and in vivo. Thus, this SGH film appears to be highly biocompatible and osteoinductive, demonstrating graphene's potential for bone regenerative medicine.
Integration of Scaffolds into Full‐Thickness Skin Wounds: The Connexin Response
Authors: Gilmartin Daniel J. , Alexaline Maia M. , Thrasivoulou Chris , Phillips Anthony R. J. , Jayasinghe Suwan N. , Becker David L. 
Published: February 2013

AbstractScaffolds have been reported to promote healing of hard‐to‐heal wounds such as burns and chronic ulcers. However, there has been little investigation into the cell biology of wound edge tissues in response to the scaffolds. Here, we assess the impact of collagen scaffolds on mouse full‐thickness wound re‐epithelialisation during the first 5 days of healing. We find that scaffolds impede wound re‐epithelialisation, inducing a bulbous thickening of the wound edge epidermis as opposed to the thin tongue of migratory keratinocytes seen in normal wound healing. Scaffolds also increase the inflammatory response and the numbers of neutrophils in and around the wound. These effects were also produced by scaffolds made of alginate in the form of fibers and microspheres, but not as an alginate hydrogel. In addition, we find the gap junction protein connexin 43, which normally down‐regulates at the wound edge during re‐epithelialisation, to be up‐regulated in the bulbous epidermal wound edge. Incorporation of connexin 43 antisense oligodeoxynucleotides into the scaffold can be performed to reduce inflammation whilst promoting scaffold biocompatibility.
Adult human nasal mesenchymal stem cells have an unexpected broad anatomic distribution
Authors: Goldstein Bradley J. , Hare Joshua M. , Lieberman Seth , Casiano Roy 
Published: February 2013

BackgroundThe olfactory epithelium is a self‐renewing tissue, able to produce new neurons as needed from stem and progenitor cells in its basal layers. In addition, there exists a mesenchymal‐like stem cell (MSC) located within the underlying lamina propria. Little is known about the function of this nasal MSC, or its relationship to the olfactory lineage, but there is considerable interest in using the nasal MSC for cell‐based therapies. We sought to further explore the biology of the nasal MSC by establishing neurosphere cultures from adult human nasal biopsies, and to examine the anatomic distribution of nasal MSCs.MethodsNasal biopsies from human patients (n = 5) were obtained from superior, middle, and inferior turbinates or septum. Tissue was cultured to obtain nasal MSCs. Cultures were analyzed by immunocytochemistry and flow cytometry, as well as for differentiation capacity.ResultsAlthough olfactory sensory neuroepithelium is restricted to superior regions in the nasal cavity, neurosphere‐forming MSC cultures were, surprisingly, obtained from olfactory as well as non‐olfactory regions. These MSC cultures exhibit characteristic robust neurosphere formation and express CD90, CD105, STRO‐1, and nestin. Nasal MSCs were found to give rise to neuronal‐like cells under differentiation conditions.ConclusionThe unanticipated broad anatomic distribution of nasal MSCs has implications for cell‐based therapy research.
A facile, green, versatile protocol to prepare polypropylene‐g‐poly(methyl methacrylate) copolymer by water‐solid phase suspension grafting polymerization using the surface of reactor granule technology polypropylene granules as reaction loci
Authors: Li Zhuo , Ma Yuhong , Yang Wantai 
Published: February 2013

AbstractA facile and environment friendly process, called water‐solid phase suspension grafting polymerization, was developed to prepare polypropylene‐g‐poly(methyl methacrylate) (PP‐g‐PMMA) copolymer with a submicrometer microdomain. In this approach, graft polymerization was elaborately regulated to occur within micropores of polypropylene particles prepared by reactor granule technology. FTIR spectra of the samples after extraction demonstrated that PMMA was successfully grafted onto the PP. The results showed grafting percentage (GP) of PMMA increased with the increasing monomer ratios to PP and that could reach 13.6%. Whereas the grafting efficiency decreased as the monomer ratio increased. The addition of second monomer styrene improved GP up to 24.5%. Differential Scanning Calorimetry tests showed that the grafting of PMMA have a slight effect on the melting point and the relative crystallinity of PP. TEM micrographs demonstrated PMMA domains distributed in PP matrix with sizes ranging from about 100 to 300 nm. In addition, Shear viscosity increased with the growing GP indicated by rheological measurement. The preliminary evaluation showed PP‐g‐PMMA was effective in improving the compatibility of PP/acrylonitrile‐styrene‐acrylate blends. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Trigonal‐Bipyramidal and Square‐Pyramidal ChromiumManganese Chalcogenide Clusters, [E2CrMn2(CO)n]2− (E=S, Se, Te; n=9, 10): Synthesis, Electrochemistry, UV/Vis Absorption, and Computational Studies
Authors: Shieh Minghuey , Yu Chun‐Hsien , Chu Yen‐Yi , Guo Yu‐Wen , Huang Chung‐Yi , Hsing Kai‐Jieah , Chen Pei‐Chi , Lee Chung‐Feng 
Published: February 2013

AbstractThe reactions of E powder (E=S, Se) with a mixture of Cr(CO)6 and Mn2(CO)10 in concentrated solutions of KOH/MeOH produced two new mixed CrMncarbonyl clusters, [E2CrMn2(CO)9]2− (E=S, 1; Se, 2). Clusters 1 and 2 were isostructural with one another and each displayed a trigonal‐bipyramidal structure, with the CrMn2 triangle axially capped by two μ3‐E atoms. The analogous telluride cluster, [Te2CrMn2(CO)9]2− (3), was obtained from the ring‐closure of Te2Mn2 ring complex [Te2Mn2Cr2(CO)18]2− (4). Upon bubbling with CO, clusters 2 and 3 were readily converted into square‐pyramidal clusters, [E2CrMn2(CO)10]2− (E=Se, 5; Te, 6), accompanied with the cleavage of one CrMn bond. According to SQUID analysis, cluster 6 was paramagnetic, with S=1 at room temperature; however, the Se analogue (5) was spectroscopically proposed to be diamagnetic, as verified by TD‐DFT calculations. Cluster 6 could be further carbonylated, with cleavage of the MnMn bond to produce a new arachno‐cluster, [Te2CrMn2(CO)11]2− (7). The formation and structural isomers, as well as electrochemistry and UV/Vis absorption, of these clusters were also elucidated by DFT calculations.
Novel Thiazolo[5,4‐d]thiazole‐Based Organic Dyes for Quasi‐Solid‐State Dye‐Sensitized Solar Cells
Authors: Zhang Weiyi , Feng Quanyou , Wang Zhong‐Sheng , Zhou Gang 
Published: February 2013

AbstractA series of novel metal‐free organic dyes containing the thiazolo[5,4‐d]thiazole moiety were designed and synthesized for quasi‐solid‐state dye‐sensitized solar cells (DSSCs). Different alkoxy chains were introduced into the electron donor part of the dye molecules for comparison. The optical, electrochemical, and photovoltaic properties for all sensitizers were systematically investigated. It was found that the sensitizers with the different alkoxy groups have similar photophysical and electrochemical properties, such as absorbance and energy levels, owing to their close chemical structures. However, the quasi‐solid‐state DSSCs based on the resulting sensitizers exhibit different performance parameters. The quasi‐solid‐state DSSC based on sensitizer FNE74 with two octyloxy chains possessed the highest solar energy conversion efficiency of 5.10 % under standard AM 1.5G sunlight illumination without the use of coadsorbant agents.
Genomically and biochemically accurate metabolic reconstruction of Methanosarcina barkeri Fusaro, iMG746
Authors: Gonnerman Matthew C. , Benedict Matthew N. , Feist Adam M. , Metcalf William W. , Price Nathan D. 
Published: February 2013

AbstractMethanosarcina barkeri is an Archaeon that produces methane anaerobically as the primary byproduct of its metabolism. M. barkeri can utilize several substrates for ATP and biomass production including methanol, acetate, methyl amines, and a combination of hydrogen and carbon dioxide. In 2006, a metabolic reconstruction of M. barkeri, iAF692, was generated based on a draft genome annotation. The iAF692 reconstruction enabled the first genome‐Scale simulations for Archaea. Since the publication of the first metabolic reconstruction of M. barkeri, additional genomic, biochemical, and phenotypic data have clarified several metabolic pathways. We have used this newly available data to improve the M. barkeri metabolic reconstruction. Modeling simulations using the updated model, iMG746, have led to increased accuracy in predicting gene knockout phenotypes and simulations of batch growth behavior. We used the model to examine knockout lethality data and make predictions about metabolic regulation under different growth conditions. Thus, the updated metabolic reconstruction of M. barkeri metabolism is a useful tool for predicting cellular behavior, studying the methanogenic lifestyle, guiding experimental studies, and making predictions relevant to metabolic engineering applications.
Flux‐coupled genes and their use in metabolic flux analysis
Authors: Kim Hyun Uk , Kim Won Jun , Lee Sang Yup 
Published: February 2013

AbstractAs large volumes of omics data have become available, systems biology is playing increasingly important roles in elucidating new biological phenomena, especially through genome‐scale metabolic network modeling and simulation. Much effort has been exerted on integrating omics data with metabolic flux simulation, but further development is necessary for more accurate flux estimation. To move one step forward, we adopted the concept of flux‐coupled genes (FCGs), which show that their expression transition patterns upon perturbations are correlated with their corresponding flux values, as additional constraints in metabolic flux analysis. It was found that gnd, pfkB, rpe, sdhB, sdhD, sucA, and zwf genes, mostly associated with pentose phosphate pathway and TCA cycle, were the most consistent FCGs in Escherichia coli based on its transcriptome and 13C‐flux data obtained from the chemostat cultivation at five different dilution rates. Consequently, constraints‐based flux analyses with FCGs as additional constraints were conducted for the seven single‐gene knockout mutants, compared with those obtained without using FCGs. This strategy of constraining the metabolic flux analysis with FCGs is expected to be useful due to the relative ease in obtaining transcriptional information in the functional genomics era.
Two Antiproliferative Triterpene Saponins from Nematostylis anthophylla from the Highlands of Central Madagascar
Authors: Dai Yumin , Harinantenaina Liva , Brodie Peggy J. , Birkinshaw Chris , Randrianaivo Richard , Applequist Wendy , Ratsimbason Michel , Rasamison Vincent E. , Shen Yongchun , TenDyke Karen , Kingston David G. I. 
Published: February 2013

AbstractInvestigation of the endemic Madagascan plant Nematostylis anthophylla (Rubiaceae) for antiproliferative activity against the A2780 ovarian cancer cell line led to the isolation of the known triterpene saponin randianin (1), and the two new bioactive triterpene saponins 2″‐O‐acetylrandianin (2) and 6″‐O‐acetylrandianin (3). The structures of the two new compounds were elucidated based on analysis of their 1D‐ and 2D‐NMR spectra, and mass spectrometric data. The three isolated triterpene saponins displayed moderate but selective antiproliferative activities, with IC50 values of 1.2, 1.7, and 2.2 μM, respectively, against the A2780 ovarian cancer, but only weak inhibitions of the proliferation of A2058 melanoma and the H522 lung cancer cell lines.
Chemical Constituents from a Soil‐Derived Actinomycete, Actinomadura miaoliensis BCRC 16873, and Their Inhibitory Activities on Lipopolysaccharide‐Induced Tumor Necrosis Factor Production
Authors: Tseng Min , Su Yung‐Shun , Cheng Ming‐Jen , Liu Ta‐Wei , Chen Ih‐Sheng , Wu Ming‐Der , Chang Hsun‐Shuo , Yuan Gwo‐Fang 
Published: February 2013

AbstractAn investigation on the secondary metabolites from the BuOH extract of the fermentation broth of the thermotolerant polyester‐degrading actinomycete Actinomadura miaoliensis BCRC 16873 was carried out. One previously undescribed α‐pyrone (=pyran‐2‐one) derivative, designated as miaolienone (1), and a new butanolide, miaolinolide (2), together with 13 known compounds, 3–15, were obtained. Their structures were established on the basis of extensive 1D‐ and 2D‐NMR analyses in combination with HR‐MS experiments. In addition, the isolated compounds 1–15 were evaluated for the inhibitory effects of the isolates on the production of tumor necrosis factor (TNF‐α) induced by lipopolysaccharide (LPS). Among the isolates, 1 and 2 significantly inhibited TNF‐α production in U937 cells in vitro, and the IC50 values were 0.59 and 0.76 μM, respectively. Compounds 3–5 displayed moderate inhibitory activities on LPS‐induced TNF‐α production.
Melanogenesis‐Inhibitory Activity of Aromatic Glycosides from the Stem Bark of Acer buergerianum
Authors: Akihisa Toshihiro , Orido Masashi , Akazawa Hiroyuki , Takahashi Akitomo , Yamamoto Ayako , Ogihara Eri , Fukatsu Makoto 
Published: February 2013

AbstractA new benzyl glucoside, 3‐O‐demethylnikoenoside (1), along with eleven known compounds, including seven aromatic glycosides, 2–8, three lignans, 9–11, and one cyclitol, 12, were isolated from the BuOH‐soluble fraction of a MeOH extract of Acer buergerianum stem bark. The structures of the new compound were elucidated on the basis of extensive spectroscopic analyses and comparison with literature. Upon evaluation of compounds 1–12 on melanogenesis in B16 melanoma cells induced with α‐melanocyte‐stimulating hormone (α‐MSH), three compounds, i.e., hovetrichoside B (8), pinoresinol 4‐O‐β‐D‐glucopyranoside (9), and pinoresinol 4‐O‐β‐D‐apiofuranosyl‐(1→2)‐β‐D‐glucopyranoside (10), have been found to exhibit inhibitory effects with 41–49% melanin content compared to the control at 100 μM and low cytotoxicity to the cells (81–92% cell viability at 100 μM). Western blot analysis showed that compound 8 reduced the protein levels of MITF (=microphtalmia‐associated transcription factor) and tyrosinase, in a concentration‐dependent manner, suggesting that 8 inhibits melanogenesis in α‐MSH‐stimulated B16 melanoma cells by, at least in part, inhibiting the expression of MITF, followed by decreasing the expression of tyrosinase. On the other hand, upon Western blotting, compound 9 was found to reduce the protein levels of tyrosinase and TRP‐2, while it increased MITF and TRP‐1 (=tyrosine‐related protein 1), in a concentration‐dependent manner, indicating that 9 inhibits melanogenesis in α‐MSH‐stimulated B16 melanoma cells by, at least in part, inhibiting the expression of tyrosinase and TRP‐2.
Stenting the arterial duct in neonates and infants with congenital heart disease and duct‐dependent pulmonary blood flow: A multicenter experience of an evolving therapy over 18 years
Authors: Udink ten Cate Floris E.A. , Sreeram Narayanswami , Hamza Hala , Agha Hala , Rosenthal Eric , Qureshi Shakeel A. 
Published: February 2013

ObjectivesThe primary aim of this multi‐institutional study was to describe our 18‐year experience of ductal stenting (DS) in infants with a duct‐dependent pulmonary circulation. The secondary aim sought to identify a subgroup of patients who may benefit the most using this evolving technique.BackgroundNo study has examined the extraordinary evolution of this promising therapy over the last two decades.MethodsBetween 1991 and 2009, 65 neonates and infants (39 male, 60%) underwent cardiac catheterization for DS in 3 participating centres. Patients were divided according to whether DS was attempted between 1991–2000 (Group 1, n = 20) or between 2001–2009 (Group 2, n = 45).ResultsDS was successful in 52/65 (80%) patients. DS outcome was associated with ductal morphology and cardiac diagnosis. DS failed more often in patients with univentricular physiology and tortuous duct morphology (p < 0.001). Most patients undergoing DS in Group 2 had pulmonary atresia with intact ventricular septum (PAIVS) (p < 0.001). DS was successful in 94% of these patients. Groups differed significantly in diameter and length of first implanted stent (p < 0.001), implanting additional stent (p < 0.001), and occurrence of complications (p = 0.033). Freedom from re‐intervention for the 52 patients was 92.3%. No procedure‐related mortality occurred.ConclusionsThe technical aspects and clinical application of percutaneous DS has changed in the last two decades. DS has become a practical and safe therapy in a subgroup of neonates with ductal‐dependent pulmonary blood flow.© 2013 Wiley Periodicals, Inc.
Three‐dimensional rotational X‐ray acquisition technique is reducing patients' cancer risk in coronary angiography
Authors: Eloot Liesbeth , Bacher Klaus , Steenbeke Femke , Drieghe Benny , Gheeraert Peter , Taeymans Yves , Thierens Hubert 
Published: February 2013

ObjectivesThe purpose of this study was to assess patient‐specific organ doses and cancer risk with 3D‐rotational acquisitions versus the current standard of multiple single‐plane coronary angiography (CA).BackgroundCatheter‐based CA remains one of the most commonly performed diagnostic invasive procedures delivering a relatively high radiation dose to the patient. With the introduction of flat‐panel technology, three‐dimensional rotational angiography became an alternative for the conventional two‐dimensional angiography. However, limited information is available on the difference in patient radiation exposure with both acquisition techniques.MethodsEighty adult patients (45 males, age 38–93 years) were randomly assigned to the rotational or standard angiography group. Exposure parameters were registered and skin dose distribution was measured during the procedure. Patient‐specific organ doses and related cancer risks were assessed with dedicated software.ResultsRotational angiograms were associated with 33% lower KAP‐values (decrease from 49.99 Gycm2 to 33.37 Gycm2, P < 0.001). A significant (P < 0.001) lower peak skin dose was measured with rotational acquisitions (80 mGy, median) versus planar imaging (172 mGy, median). Moreover, the skin dose was smoothed over the whole chest of the patient. Contrast medium consumption decreased from 104 mL to 73 mL (P < 0.001) with the use of 3D‐imaging. The reduction in radiation exposure resulted in a corresponding decrease of organ doses. The latter contributed to an overall cancer risk reduction of 21% for males and 50% for females.ConclusionsThe current study demonstrates that in CA radiation risk reduction is feasible by using a rotational acquisition technique.© 2013 Wiley Periodicals, Inc.