Beyond isolated cells: microfluidic transport of large tissue for pancreatic cancer diagnosis

NASA Astrophysics Data System (ADS)

Das, Ronnie; Murphy, Rachel G.; Seibel, Eric J.

2015-03-01

For cancer diagnoses, core biopsies (CBs) obtained from patients using coring needles (CNs) are traditionally visualized and assessed on microscope slides by pathologists after samples are processed and sectioned. A fundamental gain in optical information (i.e., diagnosis/staging) may be achieved when whole, unsectioned CBs (L = 5-20, D = 0.5-2.0 mm) are analyzed in 3D. This approach preserves CBs for traditional pathology and maximizes the diagnostic potential of patient samples. To bridge CNs/CBs with imaging, our group developed a microfluidic device that performs biospecimen preparation on unsectioned CBs for pathology. The ultimate goal is an automated and rapid point-of-care system that aids pathologists by processing tissue for advanced 3D imaging platforms. An inherent, but essential device feature is the microfluidic transport of CBs, which has not been previously investigated. Early experiments demonstrated proof-of-concept: pancreas CBs (D = 0.3-2.0 mm) of set lengths were transported in straight/curved microchannels, but dimensional tolerance and flow rates were variable, and preservation of CB integrity was uncontrolled. A second study used metal cylinder substitutes (L = 10, D = 1 mm) in microchannels to understand the transport mechanism. However, CBs are imperfectly shaped, rough, porous and viscoelastic. In this study, fresh/formalin-fixed porcine and human pancreas CBs were deposited into our device through a custom interface using clinical CNs. CB integrity (i.e., sample viability) may be assessed at every stage using an optomechanical metric: physical breaks were determined when specimen intensity profile data deviated beyond xavg + 2σ. Flow rates for human CBs were determined for several CNs, and microfluidic transport of fresh and formalin-fixed CBs was analyzed.

Cystathionine β-Synthase (CBS) Domain-containing Pyrophosphatase as a Target for Diadenosine Polyphosphates in Bacteria*

PubMed Central

Anashkin, Viktor A.; Salminen, Anu; Tuominen, Heidi K.; Orlov, Victor N.; Lahti, Reijo; Baykov, Alexander A.

2015-01-01

Among numerous proteins containing pairs of regulatory cystathionine β-synthase (CBS) domains, family II pyrophosphatases (CBS-PPases) are unique in that they generally contain an additional DRTGG domain between the CBS domains. Adenine nucleotides bind to the CBS domains in CBS-PPases in a positively cooperative manner, resulting in enzyme inhibition (AMP or ADP) or activation (ATP). Here we show that linear P1,Pn-diadenosine 5′-polyphosphates (ApnAs, where n is the number of phosphate residues) bind with nanomolar affinity to DRTGG domain-containing CBS-PPases of Desulfitobacterium hafniense, Clostridium novyi, and Clostridium perfringens and increase their activity up to 30-, 5-, and 7-fold, respectively. Ap4A, Ap5A, and Ap6A bound noncooperatively and with similarly high affinities to CBS-PPases, whereas Ap3A bound in a positively cooperative manner and with lower affinity, like mononucleotides. All ApnAs abolished kinetic cooperativity (non-Michaelian behavior) of CBS-PPases. The enthalpy change and binding stoichiometry, as determined by isothermal calorimetry, were ∼10 kcal/mol nucleotide and 1 mol/mol enzyme dimer for Ap4A and Ap5A but 5.5 kcal/mol and 2 mol/mol for Ap3A, AMP, ADP, and ATP, suggesting different binding modes for the two nucleotide groups. In contrast, Eggerthella lenta and Moorella thermoacetica CBS-PPases, which contain no DRTGG domain, were not affected by ApnAs and showed no enthalpy change, indicating the importance of the DTRGG domain for ApnA binding. These findings suggest that ApnAs can control CBS-PPase activity and hence affect pyrophosphate level and biosynthetic activity in bacteria. PMID:26400082

"The Strange Birth of 'CBS Reports'" Revisited.

ERIC Educational Resources Information Center

Baughman, James L.

Aired by the Columbia Broadcasting System (CBS) during the 1960s, "CBS Reports" proved to be one of that network's most honored efforts at television news coverage. CBS chairman, William S. Paley, based his decision to air the show on the presence of a sponsor and in response to the prospect of an open-ended Federal Communications…

Crystal structures of the CBS and DRTGG domains of the regulatory region of Clostridiumperfringens pyrophosphatase complexed with the inhibitor, AMP, and activator, diadenosine tetraphosphate.

PubMed

Tuominen, H; Salminen, A; Oksanen, E; Jämsen, J; Heikkilä, O; Lehtiö, L; Magretova, N N; Goldman, A; Baykov, A A; Lahti, R

2010-05-07

Nucleotide-binding cystathionine beta-synthase (CBS) domains serve as regulatory units in numerous proteins distributed in all kingdoms of life. However, the underlying regulatory mechanisms remain to be established. Recently, we described a subfamily of CBS domain-containing pyrophosphatases (PPases) within family II PPases. Here, we express a novel CBS-PPase from Clostridium perfringens (CPE2055) and show that the enzyme is inhibited by AMP and activated by a novel effector, diadenosine 5',5-P1,P4-tetraphosphate (AP(4)A). The structures of the AMP and AP(4)A complexes of the regulatory region of C. perfringens PPase (cpCBS), comprising a pair of CBS domains interlinked by a DRTGG domain, were determined at 2.3 A resolution using X-ray crystallography. The structures obtained are the first structures of a DRTGG domain as part of a larger protein structure. The AMP complex contains two AMP molecules per cpCBS dimer, each bound to a single monomer, whereas in the activator-bound complex, one AP(4)A molecule bridges two monomers. In the nucleotide-bound structures, activator binding induces significant opening of the CBS domain interface, compared with the inhibitor complex. These results provide structural insight into the mechanism of CBS-PPase regulation by nucleotides. Copyright 2010 Elsevier Ltd. All rights reserved.

Heterogeneity of chromatoid bodies in adult pluripotent stem cells of planarian Dugesia japonica.

PubMed

Kashima, Makoto; Kumagai, Nobuyoshi; Agata, Kiyokazu; Shibata, Norito

2016-02-01

The robust regenerative ability of planarians is known to be dependent on adult pluripotent stem cells called neoblasts. One of the morphological features of neoblasts is cytoplasmic ribonucleoprotein granules (chromatoid bodies: CBs), which resemble germ granules present in germline cells in other animals. Previously, we showed by immuno-electron microscopic analysis that DjCBC-1, a planarian Me31B/Dhh1/DDX6 homologue, which is a component of ribonucleoprotein granules, was localized in CBs in the planarian Dugesia japonica. Also, recently it was reported using another planarian species that Y12 antibody recognizing symmetrical dimethylarginine (sDMA) specifically binds to CBs in which histone mRNA is co-localized. Here, we showed by double immunostaining and RNA interference (RNAi) that DjCBC-1-containing CBs and Y12-immunoreactive CBs are distinct structures, suggesting that CBs are composed of heterogeneous populations. We also found that the Y12-immunoreactive CBs specifically contained a cytoplasmic type of planarian PIWI protein (DjPiwiC). We revealed by RNAi experiments that Y12-immunoreactive CBs may have anti-transposable element activity involving the DjPiwiC protein in the neoblasts. © 2016 Japanese Society of Developmental Biologists.

Treating Individuals With Intellectual Disabilities and Challenging Behaviors With Adapted Dialectical Behavior Therapy

PubMed Central

Brown, Julie F.; Brown, Milton Z.; Dibiasio, Paige

2013-01-01

Approximately one third of adults with intellectual and developmental disabilities have emotion dysregulation and challenging behaviors (CBs). Although research has not yet confirmed that existing treatments adequately reduce CBs in this population, dialectical behavior therapy (DBT) holds promise, as it has been shown to effectively reduce CBs in other emotionally dysregulated populations. This longitudinal single-group pilot study examined whether individuals with impaired intellectual functioning would show reductions in CBs while receiving standard DBT individual therapy used in conjunction with the Skills System (DBT-SS), a DBT emotion regulation skills curriculum adapted for individuals with cognitive impairment. Forty adults with developmental disabilities (most of whom also had intellectual disabilities) and CBs, including histories of aggression, self-injury, sexual offending, or other CBs, participated in this study. Changes in their behaviors were monitored over 4 years while in DBT-SS. Large reductions in CBs were observed during the 4 years. These findings suggest that modified DBT holds promise for effectively treating individuals with intellectual and developmental disabilities. PMID:23914278

Evaluation of CBS 600 carburized steel as a gear material

NASA Technical Reports Server (NTRS)

Townsend, D. P.; Parker, R. J.; Zaretsky, E. V.

1979-01-01

Gear endurance tests were conducted with one lot of consumable-electrode vacuum-melted (CVM) AISI 9310 gears and one lot of air-melt CBS 600 gears. The gears were 8 pitch with a pitch diameter of 8.89 centimeters (3.5 in.). Bench-type rolling-element fatigue tests were also conducted with one lot of CVM AISI 9310, three lots of CVM CBS 600, and one of air-melt CBS 600 material. The rolling-element bars were 0.952 centimeter (0.375 in.) in diameter. The CBS 600 material exhibited pitting fatigue lives in both rolling-element specimens and gears at least equivalent to that of CVM AISI 9310. Tooth fracture failure occurred with the CBS 600 gears after overrunning a fatigue spall, but it did not occur with the CVM AISI 9310 gears. Tooth fracture in the CBS 600 was attributed to excessive carbon content in the case, excessive case depth, and a higher than normal core hardness.

Effect of S-adenosyl-L-methionine (SAM), an allosteric activator of cystathionine-β-synthase (CBS) on colorectal cancer cell proliferation and bioenergetics in vitro.

PubMed

Módis, Katalin; Coletta, Ciro; Asimakopoulou, Antonia; Szczesny, Bartosz; Chao, Celia; Papapetropoulos, Andreas; Hellmich, Mark R; Szabo, Csaba

2014-09-15

Recent data show that colon cancer cells selectively overexpress cystathionine-β-synthase (CBS), which produces hydrogen sulfide (H2S), to maintain cellular bioenergetics, support tumor growth and stimulate angiogenesis and vasorelaxation in the tumor microenvironment. The purpose of the current study was to investigate the effect of the allosteric CBS activator S-adenosyl-L-methionine (SAM) on the proliferation and bioenergetics of the CBS-expressing colon cancer cell line HCT116. The non-transformed, non-tumorigenic colon epithelial cell line NCM356 was used as control. For assessment of cell proliferation, the xCELLigence system was used. Bioenergetic function was measured by Extracellular Flux Analysis. Experiments using human recombinant CBS or HCT116 homogenates complemented the cell-based studies. SAM markedly enhanced CBS-mediated H2S production in vitro, especially when a combination of cysteine and homocysteine was used as substrates. Addition of SAM (0.1-3 mM) to HCT116 cells induced a concentration-dependent increase H2S production. SAM exerted time- and concentration-dependent modulatory effects on cell proliferation. At 0.1-1 mM SAM increased HCT116 proliferation between 0 and 12 h, while the highest SAM concentration (3 mM) inhibited proliferation. Over a longer time period (12-24 h), only the lowest concentration of SAM used (0.1 mM) stimulated cell proliferation; higher SAM concentrations produced a concentration-dependent inhibition. The short-term stimulatory effects of SAM were attenuated by the CBS inhibitor aminooxyacetic acid (AOAA) or by stable silencing of CBS. In contrast, the inhibitory effects of SAM on cell proliferation was unaffected by CBS inhibition or CBS silencing. In contrast to HCT116 cells, the lower rate of proliferation of the low-CBS expressor NCM356 cells was unaffected by SAM. Short-term (1 h) exposure of HCT116 cells to SAM induced a concentration-dependent increase in oxygen consumption and bioenergetic function at 0.1-1 mM, while 3 mM was inhibitory. Longer-term (72 h) exposure of HCT116 cells to all concentrations of SAM tested suppressed mitochondrial oxygen consumption rate, cellular ATP content and cell viability. The stimulatory effect of SAM on bioenergetics was attenuated in cells with stable CBS silencing, while the inhibitory effects were unaffected. In NCM356 cells SAM exerted smaller effects on cellular bioenergetics than in HCT116 cells. We have also observed a downregulation of CBS in response to prolonged exposure of SAM both in HCT116 and NCM356 cells. Taken together, the results demonstrate that H2S production in HCT116 cells is stimulated by the allosteric CBS activator, SAM. At low-to intermediate levels and early time periods the resulting H2S serves as an endogenous cancer cell growth and bioenergetic factor. In contrast, the inhibition of cell proliferation and bioenergetic function by SAM does not appear to relate to adverse autocrine effects of H2S resulting from CBS over-stimulation but, rather to CBS-independent pharmacological effects. Copyright © 2014 Elsevier Inc. All rights reserved.

Psychometric properties of Persian version of the Caregiver Burden Scale in Iranian caregivers of patients with spinal cord injury.

PubMed

Farajzadeh, Ata; Akbarfahimi, Malahat; Maroufizadeh, Saman; Rostami, Hamid Reza; Kohan, Amir Hassan

2018-02-01

To investigate the psychometric properties of the Persian version of Caregiver Burden Scale (CBS) in caregivers of patients with spinal cord injury. This is a cross-sectional study. After a forward-backward translation, the CBS was administered to 110 caregivers of patients with spinal cord injury (men = 60, women = 50). Factor structure was evaluated by confirmatory factor analysis. The Internal consistency and test-retest reliability of the CBS were examined using Cronbach's α and the intraclass correlation coefficient, respectively. Construct validity was assessed by examining the relationship among CBS and the World Health Organization Quality of Life, and the Beck Depression Inventory. The results of confirmatory factor analysis provided support for a five-factor model of CBS. All subscales of CBS revealed acceptable internal consistency (0.698-0.755), except for environment subscale (0.559). The CBS showed adequate test-retest reliability for its subscales (0.745-0.900). All subscales of CBS significantly correlated with both Beck Depression Inventory and World Health Organization Quality of Life, confirming construct validity. The Persian version of the CBS is a valid and reliable measure for assessing burden of care in caregivers of patients with spinal cord injury. Implications for Rehabilitation Spinal cord injury leads to depression, high levels of stress and diminished quality of life due to the high physical, emotional, and social burdens in caregivers. Persian version of the Caregiver Burden Scale is a valid and reliable tool for assessing burden in Iranian caregivers of patients with spinal cord injury.

The keto-enol equilibrium in substituted acetaldehydes: focal-point analysis and ab initio limit

NASA Astrophysics Data System (ADS)

Balabin, Roman M.

2011-10-01

High-level ab initio electronic structure calculations up to the CCSD(T) theory level, including extrapolations to the complete basis set (CBS) limit, resulted in high precision energetics of the tautomeric equilibrium in 2-substituted acetaldehydes (XH2C-CHO). The CCSD(T)/CBS relative energies of the tautomers were estimated using CCSD(T)/aug-cc-pVTZ, MP3/aug-cc-pVQZ, and MP2/aug-cc-pV5Z calculations with MP2/aug-cc-pVTZ geometries. The relative enol (XHC = CHOH) stabilities (ΔE e,CCSD(T)/CBS) were found to be 5.98 ± 0.17, -1.67 ± 0.82, 7.64 ± 0.21, 8.39 ± 0.31, 2.82 ± 0.52, 10.27 ± 0.39, 9.12 ± 0.18, 5.47 ± 0.53, 7.50 ± 0.43, 10.12 ± 0.51, 8.49 ± 0.33, and 6.19 ± 0.18 kcal mol-1 for X = BeH, BH2, CH3, Cl, CN, F, H, NC, NH2, OCH3, OH, and SH, respectively. Inconsistencies between the results of complex/composite energy computations methods Gn/CBS (G2, G3, CBS-4M, and CBS-QB3) and high-level ab initio methods (CCSD(T)/CBS and MP2/CBS) were found. DFT/aug-cc-pVTZ results with B3LYP, PBE0 (PBE1PBE), TPSS, and BMK density functionals were close to the CCSD(T)/CBS levels (MAD = 1.04 kcal mol-1).

Requirements for Information/Education Programs on Hypothermia.

DTIC Science & Technology

1979-10-23

NY (NBC) WEZF - Burlington, VT (ABC) Bangor, ME: 112,800 WLBZ - Bangor, ME (NBC) WABI - Bangor, ME (CBS) WVII - Bangor, ME (ABC) Presque Isle , ME...28,700 WAGM - Presque Isle , ME CBS(ABC-NBC) A-2 MID-ATLANTIC: 18,885,600 New York, NY: 6,375,500 Raleigh-Durham, NC: 451,800 WCBS - New York, NY (CBS...NY (ABC) WICZ - Binghamton, NY (NBC) WilingonNC: 135,300 WWAY -IWilmington, NC (ABC) WECT - Wilmington, NC NBC (CBS) Erie , PA: 132,600 WICU - Erie , PA

Automated Cellient(™) cytoblocks: better, stronger, faster?

PubMed

Prendeville, S; Brosnan, T; Browne, T J; McCarthy, J

2014-12-01

Cytoblocks (CBs), or cell blocks, provide additional morphological detail and a platform for immunocytochemistry (ICC) in cytopathology. The Cellient(™) system produces CBs in 45 minutes using methanol fixation, compared with traditional CBs, which require overnight formalin fixation. This study compares Cellient and traditional CB methods in terms of cellularity, morphology and immunoreactivity, evaluates the potential to add formalin fixation to the Cellient method for ICC studies and determines the optimal sectioning depth for maximal cellularity in Cellient CBs. One hundred and sixty CBs were prepared from 40 cytology samples (32 malignant, eight benign) using four processing methods: (A) traditional; (B) Cellient (methanol fixation); (C) Cellient using additional formalin fixation for 30 minutes; (D) Cellient using additional formalin fixation for 60 minutes. Haematoxylin and eosin-stained sections were assessed for cellularity and morphology. ICC was assessed on 14 cases with a panel of antibodies. Three additional Cellient samples were serially sectioned to determine the optimal sectioning depth. Scoring was performed by two independent, blinded reviewers. For malignant cases, morphology was superior with Cellient relative to traditional CBs (P < 0.001). Cellularity was comparable across all methods. ICC was excellent in all groups and the addition of formalin at any stage during the Cellient process did not influence the staining quality. Serial sectioning through Cellient CBs showed optimum cellularity at 30-40 μm with at least 27 sections obtainable. Cellient CBs provide superior morphology to traditional CBs and, if required, formalin fixation may be added to the Cellient process for ICC. Optimal Cellient CB cellularity is achieved at 30-40 μm, which will impact on the handling of cases in daily practice. © 2014 John Wiley & Sons Ltd.

Occurrence, distribution, and dechlorination of polychlorinated biphenyls and health risk assessment in Selangor River basin.

PubMed

Sakai, Nobumitsu; Dayana, Emmy; Abu Bakar, Azizi; Yoneda, Minoru; Nik Sulaiman, Nik Meriam; Ali Mohd, Mustafa

2016-10-01

Polychlorinated biphenyls (PCBs) were monitored in surface water collected in the Selangor River basin, Malaysia, to identify the occurrence, distribution, and dechlorination process as well as to assess the potential adverse effects to the Malaysian population. Ten PCB homologs (i.e., mono-CBs to deca-CBs) were quantitated by using gas chromatography-mass spectrometry (GC/MS). The total concentration of PCBs in the 10 sampling sites ranged from limit of detection to 7.67 ng L -1 . The higher chlorinated biphenyls (tetra-CBs to deca-CBs) were almost not detected in most of the sampling sites, whereas lower chlorinated biphenyls (mono-CBs, di-CBs, and tri-CBs) dominated more than 90 % of the 10 homologs in all the sampling sites. Therefore, the PCB load was estimated to be negligible during the sampling period because PCBs have an extremely long half-life. The PCBs, particularly higher chlorinated biphenyls, could be thoroughly dechlorinated to mono-CBs to tri-CBs by microbial decomposition in sediment or could still be accumulated in the sediment. The lower chlorinated biphenyls, however, could be resuspended or desorbed from the sediment because they have faster desorption rates and higher solubility, compared to the higher chlorinated biphenyls. The health risk for the Malaysia population by PCB intake that was estimated from the local fish consumption (7.2 ng kg -1 bw day -1 ) and tap water consumption (1.5 × 10 -3 -3.1 × 10 -3  ng kg -1 bw day -1 ) based on the detected PCB levels in the surface water was considered to be minimal. The hazard quotient based on the tolerable daily intake (20 ng kg -1 bw day -1 ) was estimated at 0.36.

Estrogen Replacement Therapy in Ovariectomized Nonpregnant Ewes Stimulates Uterine Artery Hydrogen Sulfide Biosynthesis by Selectively Up-Regulating Cystathionine β-Synthase Expression

PubMed Central

Lechuga, Thomas J.; Zhang, Hong-hai; Sheibani, Lili; Karim, Muntarin; Jia, Jason; Magness, Ronald R.; Rosenfeld, Charles R.

2015-01-01

Estrogens dramatically dilate numerous vascular beds with the greatest response in the uterus. Endogenous hydrogen sulfide (H2S) is a potent vasodilator and proangiogenic second messenger, which is synthesized from L-cysteine by cystathionine β-synthase (CBS) and cystathionine γ-lyase (CSE). We hypothesized that estrogen replacement therapy (ERT) selectively stimulates H2S biosynthesis in uterine artery (UA) and other systemic arteries. Intact and endothelium-denuded UA, mesenteric artery (MA), and carotid artery (CA) were obtained from ovariectomized nonpregnant ewes (n = 5/group) receiving vehicle or estradiol-17β replacement therapy (ERT). Total RNA and protein were extracted for measuring CBS and CSE, and H2S production was determined by the methylene blue assay. Paraffin-embedded UA rings were used to localize CBS and CSE proteins by immunofluorescence microscopy. ERT significantly stimulated CBS mRNA and protein without altering CSE mRNA or protein in intact and denuded UA. Quantitative immunofluorescence microscopic analyses showed CBS and CSE protein localization in endothelium and smooth muscle and confirmed that ERT stimulated CBS but not CSE protein expression in UA endothelium and smooth muscle. ERT also stimulated CBS, but not CSE, mRNA and protein expression in intact and denuded MA but not CA in ovariectomized ewes. Concomitantly, ERT stimulated UA and MA but not CA H2S production. ERT-stimulated UA H2S production was completely blocked by a specific CBS but not CSE inhibitor. Thus, ERT selectively stimulates UA and MA but not CA H2S biosynthesis by specifically up-regulating CBS expression, implicating a role of H2S in estrogen-induced vasodilation and postmenopausal women's health. PMID:25825818

Estrogen Replacement Therapy in Ovariectomized Nonpregnant Ewes Stimulates Uterine Artery Hydrogen Sulfide Biosynthesis by Selectively Up-Regulating Cystathionine β-Synthase Expression.

PubMed

Lechuga, Thomas J; Zhang, Hong-hai; Sheibani, Lili; Karim, Muntarin; Jia, Jason; Magness, Ronald R; Rosenfeld, Charles R; Chen, Dong-bao

2015-06-01

Estrogens dramatically dilate numerous vascular beds with the greatest response in the uterus. Endogenous hydrogen sulfide (H2S) is a potent vasodilator and proangiogenic second messenger, which is synthesized from L-cysteine by cystathionine β-synthase (CBS) and cystathionine γ-lyase (CSE). We hypothesized that estrogen replacement therapy (ERT) selectively stimulates H2S biosynthesis in uterine artery (UA) and other systemic arteries. Intact and endothelium-denuded UA, mesenteric artery (MA), and carotid artery (CA) were obtained from ovariectomized nonpregnant ewes (n = 5/group) receiving vehicle or estradiol-17β replacement therapy (ERT). Total RNA and protein were extracted for measuring CBS and CSE, and H2S production was determined by the methylene blue assay. Paraffin-embedded UA rings were used to localize CBS and CSE proteins by immunofluorescence microscopy. ERT significantly stimulated CBS mRNA and protein without altering CSE mRNA or protein in intact and denuded UA. Quantitative immunofluorescence microscopic analyses showed CBS and CSE protein localization in endothelium and smooth muscle and confirmed that ERT stimulated CBS but not CSE protein expression in UA endothelium and smooth muscle. ERT also stimulated CBS, but not CSE, mRNA and protein expression in intact and denuded MA but not CA in ovariectomized ewes. Concomitantly, ERT stimulated UA and MA but not CA H2S production. ERT-stimulated UA H2S production was completely blocked by a specific CBS but not CSE inhibitor. Thus, ERT selectively stimulates UA and MA but not CA H2S biosynthesis by specifically up-regulating CBS expression, implicating a role of H2S in estrogen-induced vasodilation and postmenopausal women's health.

Short-term hot-hardness characteristics of five case hardened steels

NASA Technical Reports Server (NTRS)

Anderson, N. E.; Zaretsky, E. V.

1975-01-01

Short-term hot-hardness studies were performed with carburized and hardened AISI 8620, CBS 1000, CBS 1000M, CBS 600, and Vasco X-2 steels. Case and core hardness measurements were made at temperatures from 294 to 811 K (70 to 1000 F). The data were compared with data for high-speed tool steels and AISI 52100. The materials tested can be ranked as follows in order of decreasing hot-hardness retention: (1) Vasco X-2; equivalent to through-hardened tool steels up to 644 K (700 F) above which Vasco X-2 is inferior; (2) CBS 1000, (3) CBS 1000M; (4) CBS 6000; better hardness retention at elevated temperatures than through-hardened AISI 52100; and (5) AISI 8620. For the carburized steels, the change in hardness with temperature of the case and core are similar for a given material. The short-term hot hardness of these materials can be predicted with + or - 1 point Rockwell C.

The effectiveness and cost-effectiveness of community-based support for adolescents receiving antiretroviral treatment: an operational research study in South Africa.

PubMed

Fatti, Geoffrey; Jackson, Debra; Goga, Ameena E; Shaikh, Najma; Eley, Brian; Nachega, Jean B; Grimwood, Ashraf

2018-02-01

Adolescents and youth receiving antiretroviral treatment (ART) in sub-Saharan Africa have high attrition and inadequate ART outcomes, and evaluations of interventions improving ART outcomes amongst adolescents are very limited. Sustainable Development Goal (SDG) target 3c is to substantially increase the health workforce in developing countries. We measured the effectiveness and cost-effectiveness of community-based support (CBS) provided by lay health workers for adolescents and youth receiving ART in South Africa. A retrospective cohort study including adolescents and youth who initiated ART at 47 facilities. Previously unemployed CBS-workers provided home-based ART-related education, psychosocial support, symptom screening for opportunistic infections and support to access government grants. Outcomes were compared between participants who received CBS plus standard clinic-based care versus participants who received standard care only. Cumulative incidences of all-cause mortality and loss to follow-up (LTFU), adherence measured using medication possession ratios (MPRs), CD4 count slope, and virological suppression were analysed using multivariable Cox, competing-risks regression, generalized estimating equations and mixed-effects models over five years of ART. An expenditure approach was used to determine the incremental cost of CBS to usual care from a provider perspective. Incremental cost-effectiveness ratios were calculated as annual cost per patient-loss (through death or LTFU) averted. Amongst 6706 participants included, 2100 (31.3%) received CBS. Participants who received CBS had reduced mortality, adjusted hazard ratio (aHR) = 0.52 (95% CI: 0.37 to 0.73; p < 0.0001). Cumulative LTFU was 40% lower amongst participants receiving CBS (29.9%) compared to participants without CBS (38.9%), aHR = 0.60 (95% CI: 0.51 to 0.71); p < 0.0001). The effectiveness of CBS in reducing attrition ranged from 42.2% after one year to 35.9% after five years. Virological suppression was similar after three years, but after five years 18.8% CBS participants versus 37.2% non-CBS participants failed to achieve viral suppression, adjusted odds ratio = 0.24 (95% CI: 0.06 to 1.03). There were no significant differences in MPR or CD4 slope. The cost of CBS was US$49.5/patient/year. The incremental cost per patient-loss averted was US$600 and US$776 after one and two years, respectively. CBS for adolescents and youth receiving ART was associated with substantially reduced patient attrition, and is a low-cost intervention with reasonable cost-effectiveness that can aid progress towards several health, economic and equality-related SDG targets. © 2018 The Authors. Journal of the International AIDS Society published by John Wiley & sons Ltd on behalf of the International AIDS Society.

Cystathionine-β-synthase-derived hydrogen sulfide is required for amygdalar long-term potentiation and cued fear memory in rats.

PubMed

Chen, Hai-Bo; Wu, Wen-Ning; Wang, Wei; Gu, Xun-Hu; Yu, Bin; Wei, Bo; Yang, Yuan-Jian

2017-04-01

Hydrogen sulfide (H 2 S) is an endogenous gaseous molecule that functions as a neuromodulator in the brain. We previously reported that H 2 S regulated amygdalar synaptic plasticity and cued fear memory in rats. However, whether endogenous H 2 S is required for amygdalar long-term potentiation (LTP) induction and cued fear memory formation remains unclear. Here, we show that cystathionine-β-synthase (CBS), the predominant H 2 S-producing enzyme in the brain, was highly expressed in the amygdala of rats. Suppressing CBS activity by inhibitor prevented activity-triggered generation of H 2 S in the lateral amygdala (LA) region. Incubating brain slices with CBS inhibitor significantly prevented the induction of NMDA receptors (NMDARs)-dependent LTP in the thalamo-LA pathway, and intra-LA infusion of CBS inhibitor impaired cued fear memory in rats. Notably, treatment with H 2 S donor, but not CBS activator, significantly reversed the impairments of LTP and fear memory caused by CBS inhibition. Mechanismly, inhibition of CBS activity led to a reduction in NMDAR-mediated synaptic response in the thalamo-LA pathway, and treatment with H 2 S donor restored the function of NMDARs. Collectively, these results indicate that CBS-derived H 2 S is required for amygdalar synaptic plasticity and cued fear memory in rats, and the effects of endogenous H 2 S might involve the regulation of NMDAR function. Copyright © 2017 Elsevier Inc. All rights reserved.

The protective activity of Conyza blinii saponin against acute gastric ulcer induced by ethanol.

PubMed

Ma, Long; Liu, Jiangguang

2014-12-02

Conyza blinii H.Lév., is a type of natural plant. Its dried overground section is used to treat infections and inflammations in traditional Chinese medicine. Triterpenoidal saponins have a wide range of bioactivities, for instance, anti-cancer, anti-virus and anti-anaphylaxis. Conyza blinii saponin (CBS), mainly composed of triterpenoidal saponins, is the total saponin of Conyza blinii H.Lév. It has been reported that CBS also has gastric mucous membrane protection activity. This study aims to test CBS׳s protective activity of gastric׳s mucous membrane against ethanol. This investigation may lead to the development of novel drug from natural products as anti-ulcer agent, or as gastric mucous protective against chemical damage. CBS (Conyza blinii saponin) is the total saponin of Conyza blinii H.Lév., which was obtained as described previously. We tested the protective activity of CBS against ethanol-induced ulcer. Thirty six rats were grouped randomly as 'NORMAL', 'CONTROL', 'MODEL', 'LOW DOSE', 'MEDIUM DOSE' and 'HIGH DOSE'. The 'NORMAL' group were rats with no pathological model established within it. The 'CONTROL' group was administrated with colloidal bismuth subcitrate, while 'MODEL' group was not given any active agents apart from absolute ethanol in order to obtain gastric ulcer model. The three 'DOSE' groups were treated with different concentrations of CBS (5, 10, 20mg/mL) before administration followed by absolute ethanol. All rats were sacrificed after the experiment to acquire the gastric tissue. The ulcer index (UI), malondialdehyde (MDA) and superoxide dismutase (SOD) were measured to monitor the activity of CBS. Besides, the rat gastric tissue was made to paraffin section and stained using the Hematoxylin-Eosin (HE) method. The histopathology examination was carried out to examine CBS efficacy in terms of gastric mucous protection. We found that CBS had a profound protection activity against acute gastric ulcer induced by ethanol and this activity displayed a concentration-dependent manner. The efficacy of 10 and 20mg/mL CBS was comparable with colloidal bismuth subcitrate (P<0.05). All three level of CBS tested were able to significantly reduce UI, MDA and enhance SOD level (P<0.05). It was deduced that the mechanism for such activity would be anti-lipid peroxidation, facilitating free radicals clearance. In addition , histopathology examination of the gastric mucous membrane supported the same conclusion, that CBS can efficiently suppress the inflammatory reactions, bleeding and protect the gastric mucosa. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Five novel Wickerhamomyces- and Metschnikowia-related yeast species, Wickerhamomyces chaumierensis sp. nov., Candida pseudoflosculorum sp. nov., Candida danieliae sp. nov., Candida robnettiae sp. nov. and Candida eppingiae sp. nov., isolated from plants.

PubMed

Groenewald, Marizeth; Robert, Vincent; Smith, Maudy Th

2011-08-01

On the basis of nucleotide divergences in the D1/D2 domain of the 26S rRNA gene and the internal transcribed spacers (ITS) domain of the rRNA gene, five novel yeast species, Wickerhamomyces chaumierensis sp. nov. (CBS 8565(T)  = JCM 17246(T)), Candida pseudoflosculorum sp. nov. (CBS 8584(T)  = JCM 17242(T)), Candida danieliae sp. nov. (CBS 8533(T)  = JCM 17247(T)), Candida robnettiae sp. nov. (CBS 8580(T)  = JCM 17243(T)) and Candida eppingiae sp. nov. (CBS 8586(T)  = JCM 17241(T)), isolated from plants in Thailand and Guyana, are proposed in this study.

Cystathionine β-Synthase Inhibition Is a Potential Therapeutic Approach to Treatment of Ischemic Injury

PubMed Central

Chan, Su Jing; Chai, Chou; Lim, Tze Wei; Yamamoto, Mie; Lo, Eng H; Lai, Mitchell Kim Peng

2015-01-01

Hydrogen sulfide (H2S) has been reported to exacerbate stroke outcome in experimental models. Cystathionine β-synthase (CBS) has been implicated as the predominant H2S-producing enzyme in central nervous system. When SH-SY5Y cells were transfected to overexpress CBS, these cells were able to synthesize H2S when exposed to high levels of enzyme substrates but not substrate concentrations that may reflect normal physiological conditions. At the same time, these cells demonstrated exacerbated cell death when subjected to oxygen and glucose deprivation (OGD) together with high substrate concentrations, indicating that H2S production has a detrimental effect on cell survival. This effect could be abolished by CBS inhibition. The same effect was observed with primary astrocytes exposed to OGD and high substrates or sodium hydrosulfide. In addition, CBS was upregulated and activated by truncation in primary astrocytes subjected to OGD. When rats were subjected to permanent middle cerebral artery occlusion, CBS activation was also observed. These results imply that in acute ischemic conditions, CBS is upregulated and activated by truncation causing an increased production of H2S, which exacerbate the ischemic injuries. Therefore, CBS inhibition may be a viable approach to stroke treatment. PMID:25873304

Investigation of the synergistic effects of haloperidol combined with Calculus Bovis Sativus in treating MK-801-induced schizophrenia in rats

PubMed Central

Lei, Kai; He, Guo-Fang; Zhang, Cheng-Liang; Liu, Ya-Nan; Li, Juan; He, Guang-Zhao; Li, Xi-Ping; Ren, Xiu-Hua; Liu, Dong

2017-01-01

Clinical studies that focused on treating schizophrenia showed that Calculus Bovis Sativus (CBS), a substitute of Calculus Bovis, when used in combination with haloperidol could significantly lower the dosage of haloperidol compared with treatment with haloperidol alone, whereas efficacy was maintained. The aim of this study was to investigate the synergetic anti-schizophrenia effects in rats using CBS in combination with haloperidol. An open field test was conducted to verify the pharmacodynamic effects of a combination treatment of CBS and haloperidol on MK-801-induced schizophrenic rats. Rat plasma concentrations of intragastric haloperidol and intravenous haloperidol were determined after oral administration of a single dose or 1-week of pretreatment with CBS (50 mg/kg). The pharmacodynamic data showed a significant decrease in locomotor activity and an increase in the percentage of the central distance when haloperidol was concomitantly administered with CBS compared with haloperidol administration alone. The AUC0-∞ and Cmax of haloperidol in the orally coadministered groups were significantly higher compared with the oral treatment with haloperidol alone. In conclusion, oral coadministration of CBS with haloperidol resulted in a synergistic effect in rats. The enhanced oral bioavailability of haloperidol when combined with CBS might be attributed to the interaction between them. PMID:29225304

Cystathionine beta synthase gene dose dependent vascular remodeling in murine model of hyperhomocysteinemia.

PubMed

Tyagi, Neetu; Qipshidze, Natia; Sen, Utpal; Rodriguez, Walter; Ovechkin, Alexander; Tyagi, Suresh C

2011-09-30

Although children born with severe homocystinurea (i.e. cystathionine beta synthase homozygote knockout, CBS-/-) develop deleterious vascular complications with structural malformation and do not live past teenage, the heterozygote (CBS-/+) lives with apparently normal phenotype. Interestingly, this differential role of CBS expression in vascular remodeling is unclear. Peroxisome proliferator activated receptor gamma (PPARγ) is nuclear transcription factor that mitigates vascular complications. The hypothesis was that homocysteine (Hcy) decreased thioredoxin (Trx), peroxiredoxin (Prx), increased NADPH oxidase (NOX1), mitochondrial nitric oxide synthase (mtNOS) activity and reactive oxygen species (ROS) in mitochondria in a CBS gene dose-dependent manner. ROS transduced matrix metalloproteinase (MMP) activation causing thickening (fibrosis) of the basement membrane, rendering ineffective endothelial nitric oxide synthase (eNOS) and promoted endothelial-smooth muscle disconnection/uncoupling by antagonizing PPARγ. Wild type (WT-CBS+/+), CBS-/+ and CBS -/- mice were treated with or without ciglitazone (CZ, a PPARγ agonist) in food at birth. Aortic nuclear PPARγ expression was measured by EMSA. Aortic mtNOS activity and ROS production was measured using NO- and H(2)O(2)-electrodes, respectively. Aorta was analyzed for Trx, Prx, by Western blot, and PCR. MMP activity was by in situ zymography. Aortic function was measured in tissue myobath. The results suggested 90% morbidity in CBS-/- allele at 12 wks. However, treatment with the PPARγ agonist, CZ significantly reduced the morbidity to 20%. In addition, CZ restored the PPARγ activity in CBS-/+ and -/- mice to normal levels. The oxidative stress was alleviated by CZ treatment. In situ labeling with mito-tracker suggests co-localization of ROS with mitochondrial mitophagy. The mtNOS activity was increased in HHcy compared to WT. The data support the notion that Hcy decreases redoxins, increases mtNOS activity and ROS/oxidase in mitochondrial mitophagy in a gene dose-dependent manner of CBS. ROS transduces MMP activation, rendering ineffective eNOS and promotes endothelial-smooth muscle disconnection/uncoupling by antagonizing PPARγ. We suggest that the children born with severe ho-mocystineurea may do better if treated with PPARγ agonist.

Hepatoprotective effect of calculus bovis sativus on nonalcoholic fatty liver disease in mice by inhibiting oxidative stress and apoptosis of hepatocytes

PubMed Central

He, Wenxi; Xu, Yanjiao; Zhang, Chengliang; Lu, Jingli; Li, Juan; Xiang, Dong; Yang, Jinyu; Chang, Mujun; Liu, Dong

2017-01-01

Calculus bovis (CB, niu-huang) is a high-class therapeutic drug that is often used in traditional Chinese medicine. CB helps to eliminate heat and toxic components, and prevents the accumulation of phlegm and blood stasis in the liver. In Asian countries, CB Sativus (CBS), an ideal substitute for natural CB, is presently extensively used for long-term treatment of chronic liver diseases. The present study aimed to evaluate the effects and potential mechanism(s) of action of CBS on mice with fructose-induced nonalcoholic fatty liver disease (NAFLD). The NAFLD model was established in C57BL/6 mice by exclusively feeding fluids containing 30% fructose for 8 consecutive weeks. After these 8 weeks, mice were given CBS (50 mg/kg/day or 100 mg/kg/day) for 2 consecutive weeks. Treatment with CBS reversed the fructose-induced impaired glucose tolerance. Compared with the model group, in which mice received 8 weeks of high-fructose diet and 2 weeks of 0.5% sodium carboxymethyl cellulose, CBS treatment significantly decreased the levels of fasting serum glucose, fasting insulin, triglyceride, and total cholesterol, and increased levels of high-density lipoprotein-cholesterol. CBS treatment also significantly decreased the levels of triglyceride, total cholesterol, and free fatty acid in the liver. The activity of superoxide dismutase in the liver was increased after treatment with CBS, however, levels of malondialdehyde and reactive oxygen species decreased. Histopathological examination showed that liver steatosis and injury were significantly reduced in CBS-treated mice. The expression of fatty acid synthase, nuclear factor kappa-light-chain-enhancer of activated B cells, Cysteinyl aspartate-specific proteinase-3, and synonyms B-cell leukemia/lymphoma-2 gene-associated X protein were downregulated after treatment with CBS, whereas the expression of nuclear factor erythroid-2-related factor 2 was upregulated. In conclusion, CBS treatment exerted therapeutic effects in the liver of mice with NAFLD, which may be associated with amelioration of metabolic disorders, enhanced antioxidant effects, and alleviation of apoptosis. PMID:29255346

Similar Outcomes for Contact Aspiration and Stent Retriever Use According to the Admission Clot Burden Score in ASTER.

PubMed

Zhu, François; Lapergue, Bertrand; Kyheng, Maéva; Blanc, Raphael; Labreuche, Julien; Ben Machaa, Malek; Duhamel, Alain; Marnat, Gautier; Saleme, Suzana; Costalat, Vincent; Bracard, Serge; Richard, Sébastien; Desal, Hubert; Mazighi, Mikael; Consoli, Arturo; Piotin, Michel; Gory, Benjamin

2018-07-01

The clot burden score (CBS) at admission reliably evaluates the thrombus burden in acute ischemic stroke patients with anterior circulation large vessel occlusion. Mechanical thrombectomy has been diversified, especially with contact aspiration technique, and its efficiency with respect to the thrombus burden is not known. We compared reperfusion, adverse events, neurological recovery, and 90-day functional outcome of stent retriever use versus contact aspiration according to the admission CBS. This is a post hoc analysis of the ASTER (Contact Aspiration Versus Stent Retriever for Successful Revascularization) randomized trial. The primary outcome was successful reperfusion after all procedures, defined as modified Thrombolysis in Cerebral Infarction scores 2b/3. Secondary outcomes were 90-day functional outcome, assessed with the modified Rankin Scale. Safety outcomes included 90-day mortality and any intracerebral hemorrhage. A total of 231 randomized patients were included in this study: 114 patients had a CBS of 0 to 6 and 117 a CBS ≥7 at admission. Successful reperfusion at procedure end was achieved more frequently in patients with CBS ≥7 (88.9%) than patients with a CBS 0 to 6 (81.6%; fully adjusted risk ratio, 1.09; 95% confidence interval, 1.01-1.28). Favorable outcome (modified Rankin Scale score, 0-2) at 90 days was achieved in significantly more patients with CBS ≥7 (61.9%) than in patients with CBS 0 to 6 (41.8%; fully adjusted risk ratio, 1.19; 95% confidence interval, 1.02-1.40). No outcome differences of first-line mechanical thrombectomy strategy (aspiration versus stent) on any angiographic or clinical outcomes were observed between the 2 groups. We also found no evidence of interaction between first-line mechanical thrombectomy strategy and CBS groups regarding safety. First-line mechanical thrombectomy with contact aspiration compared with stent retriever did not result in an increased successful reperfusion rate in acute ischemic stroke patients with large vessel occlusion of the anterior circulation according to the admission CBS. The latter, however, seems to be a reliable prognostic indicator of angiographic and clinical outcome. © 2018 American Heart Association, Inc.

Determination of Tinopal CBS-X in rice papers and rice noodles using HPLC with fluorescence detection and LC-MS/MS.

PubMed

Ko, Kyung Yuk; Lee, Chae A; Choi, Jae Chon; Kim, Meehye

2014-01-01

To date there have been no reports of methods to determine Tinopal CBS-X. We developed a rapid and simple method to determine the Tinopal CBS-X content in rice noodles and rice papers using HPLC equipped with fluorescence detection. Heating the rice noodles and rice papers to 80°C after adding 75% methanol solution induced the release of Tinopal CBS-X from processed rice products. Tinopal CBS-X was separated using an isocratic mobile phase comprising 50% acetonitrile/water containing 0.4% tetrabutyl ammonium hydrogen sulphate at pH 8.0. The samples suspected to be positive by HPLC analysis were then confirmed by LC-MS/MS analysis. This study also investigated the Tinopal CBS-X content of three rice noodle products and two rice papers. The limits of quantification for rice papers and rice noodles were 1.58 and 1.51 µg kg(-1), respectively, and their correlation curves showed good linearity with r(2) ≥ 0.9997 and ≥ 0.9998, respectively. Moreover, rice papers had recoveries of 70.3-83.3% with precision ranging from 5.0% to 7.9%, whereas rice noodles had slightly lower recoveries of 63.4-78.7% and precisions of 8.5-11.5%. Only one rice noodle product contained Tinopal CBS-X, at around 2.1 mg kg(-1), whereas it was not detected in four other samples. Consequently, Tinopal CBS-X from rice noodles and rice papers can be successfully detected using the developed pre-treatment and ion-pairing HPLC system coupled with fluorescence detection.

Impact Analysis of Flow Shaping in Ethernet-AVB/TSN and AFDX from Network Calculus and Simulation Perspective

PubMed Central

He, Feng; Zhao, Lin; Li, Ershuai

2017-01-01

Ethernet-AVB/TSN (Audio Video Bridging/Time-Sensitive Networking) and AFDX (Avionics Full DupleX switched Ethernet) are switched Ethernet technologies, which are both candidates for real-time communication in the context of transportation systems. AFDX implements a fixed priority scheduling strategy with two priority levels. Ethernet-AVB/TSN supports a similar fixed priority scheduling with an additional Credit-Based Shaper (CBS) mechanism. Besides, TSN can support time-triggered scheduling strategy. One direct effect of CBS mechanism is to increase the delay of its flows while decreasing the delay of other priority ones. The former effect can be seen as the shaping restriction and the latter effect can be seen as the shaping benefit from CBS. The goal of this paper is to investigate the impact of CBS on different priority flows, especially on the intermediate priority ones, as well as the effect of CBS bandwidth allocation. It is based on a performance comparison of AVB/TSN and AFDX by simulation in an automotive case study. Furthermore, the shaping benefit is modeled based on integral operation from network calculus perspective. Combing with the analysis of shaping restriction and shaping benefit, some configuration suggestions on the setting of CBS bandwidth are given. Results show that the effect of CBS depends on flow loads and CBS configurations. A larger load of high priority flows in AVB tends to a better performance for the intermediate priority flows when compared with AFDX. Shaping benefit can be explained and calculated according to the changing from the permitted maximum burst. PMID:28531158

IMPAIRED VERBAL COMPREHENSION OF QUANTIFIERS IN CORTICOBASAL SYNDROME

PubMed Central

Troiani, Vanessa; Clark, Robin; Grossman, Murray

2011-01-01

Objective Patients with Corticobasal Syndrome (CBS) have atrophy in posterior parietal cortex. This region of atrophy has been previously linked with their quantifier comprehension difficulty, but previous studies used visual stimuli, making it difficult to account for potential visuospatial deficits in CBS patients. The current study evaluated comprehension of generalized quantifiers using strictly verbal materials. Method CBS patients, a brain-damaged control group (consisting of Alzheimer's Disease and frontotemporal dementia), and age-matched controls participated in this study. We assessed familiar temporal, spatial, and monetary domains of verbal knowledge comparatively. Judgment accuracy was only evaluated in statements for which patients demonstrated accurate factual knowledge about the target domain. Results We found that patients with CBS are significantly impaired in their ability to evaluate quantifiers compared to healthy seniors and a brain-damaged control group, even in this strictly visual task. This impairment was seen in the vast majority of individual CBS patients. Conclusions These findings offer additional evidence of quantifier impairment in CBS patients and emphasize that this impairment cannot be attributed to potential spatial processing impairments in patients with parietal disease. PMID:21381823

Bandoniozyma gen. nov., a Genus of Fermentative and Non-Fermentative Tremellaceous Yeast Species

PubMed Central

Landell, Melissa Fontes; Crestani, Juliana; Pagnocca, Fernando Carlos; Sette, Lara Durães; Passarini, Michel Rodrigo Zambrano; Rosa, Carlos Augusto; Brandão, Luciana R.; Pimenta, Raphael S.; Ribeiro, José Roberto; Garcia, Karina Marques; Lee, Ching-Fu; Suh, Sung-Oui; Péter, Gábor; Dlauchy, Dénes; Fell, Jack W.; Scorzetti, Gloria; Theelen, Bart; Vainstein, Marilene H.

2012-01-01

Background Independent surveys across the globe led to the proposal of a new basidiomycetous yeast genus within the Bulleromyces clade of the Tremellales, Bandoniozyma gen. nov., with seven new species. Methodology/Principal Findings The species were characterized by multiple methods, including the analysis of D1/D2 and ITS nucleotide sequences, and morphological and physiological/biochemical traits. Most species can ferment glucose, which is an unusual trait among basidiomycetous yeasts. Conclusions/Significance In this study we propose the new yeast genus Bandoniozyma, with seven species Bandoniozyma noutii sp. nov. (type species of genus; CBS 8364T  =  DBVPG 4489T), Bandoniozyma aquatica sp. nov. (UFMG-DH4.20T  =  CBS 12527T  =  ATCC MYA-4876T), Bandoniozyma complexa sp. nov. (CBS 11570T  =  ATCC MYA-4603T  =  MA28aT), Bandoniozyma fermentans sp. nov. (CBS 12399T  =  NU7M71T  =  BCRC 23267T), Bandoniozyma glucofermentans sp. nov. (CBS 10381T  =  NRRL Y-48076T  =  ATCC MYA-4760T  =  BG 02-7-15-015A-1-1T), Bandoniozyma tunnelae sp. nov. (CBS 8024T  =  DBVPG 7000T), and Bandoniozyma visegradensis sp. nov. (CBS 12505T  =  NRRL Y-48783T  =  NCAIM Y.01952T). PMID:23056233

Temperature and host preferences drive the diversification of Saccharomyces and other yeasts: a survey and the discovery of eight new yeast species.

PubMed

Sylvester, Kayla; Wang, Qi-Ming; James, Brielle; Mendez, Russell; Hulfachor, Amanda Beth; Hittinger, Chris Todd

2015-05-01

Compared to its status as an experimental model system and importance to industry, the ecology and genetic diversity of the genus Saccharomyces has received less attention. To investigate systematically the biogeography, community members and habitat of these important yeasts, we isolated and identified nearly 600 yeast strains using sugar-rich enrichment protocols. Isolates were highly diverse and contained representatives of more than 80 species from over 30 genera, including eight novel species that we describe here: Kwoniella betulae f.a. (yHKS285(T) = NRRL Y-63732(T) = CBS 13896(T)), Kwoniella newhampshirensis f.a. (yHKS256(T) = NRRL Y-63731(T) = CBS 13917(T)), Cryptococcus wisconsinensis (yHKS301(T) = NRRL Y-63733(T) = CBS 13895(T)), Cryptococcus tahquamenonensis (yHAB242(T) = NRRL Y-63730(T) = CBS 13897(T)), Kodamaea meredithiae f.a. (yHAB239(T) = NRRL Y-63729(T) = CBS 13899(T)), Blastobotrys buckinghamii (yHAB196(T) = NRRL Y-63727(T) = CBS 13900(T)), Candida sungouii (yHBJ21(T) = NRRL Y-63726(T) = CBS 13907(T)) and Cyberlindnera culbertsonii f.a. (yHAB218(T) = NRRL Y-63728(T) = CBS 13898(T)), spp. nov. Saccharomyces paradoxus was one of the most frequently isolated species and was represented by three genetically distinct lineages in Wisconsin alone. We found a statistically significant association between Quercus (oak) samples and the isolation of S. paradoxus, as well as several novel associations. Variation in temperature preference was widespread across taxonomic ranks and evolutionary timescales. This survey highlights the genetic and taxonomic diversity of yeasts and suggests that host and temperature preferences are major ecological factors. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Limb immobilization and corticobasal syndrome.

PubMed

Graff-Radford, Jonathan; Boeve, Bradley F; Drubach, Daniel A; Knopman, David S; Ahlskog, J Eric; Golden, Erin C; Drubach, Dina I; Petersen, Ronald C; Josephs, Keith A

2012-12-01

Recently, we evaluated two patients with corticobasal syndrome (CBS) who reported symptom onset after limb immobilization. Our objective was to investigate the association between trauma, immobilization and CBS. The charts of forty-four consecutive CBS patients seen in the Mayo Clinic Alzheimer Disease Research Center were reviewed with attention to trauma and limb immobilization. 10 CBS patients (23%) had immobilization or trauma on the most affected limb preceding the onset or acceleration of symptoms. The median age at onset was 61. Six patients manifested their first symptoms after immobilization from surgery or fracture with one after leg trauma. Four patients had pre-existing symptoms of limb dysfunction but significantly worsened after immobilization or surgery. 23 percent of patients had immobilization or trauma of the affected limb. This might have implications for management of CBS, for avoiding injury, limiting immobilization and increasing movement in the affected limb. Copyright © 2012 Elsevier Ltd. All rights reserved.

Does powder and granular activated carbon perform equally in immobilizing chlorobenzenes in soil?

PubMed

Song, Yang; Wang, Fang; Kengara, Fredrick Orori; Bian, Yongrong; Yang, Xinglun; Gu, Chenggang; Ye, Mao; Jiang, Xin

2015-01-01

The objective of this study is to compare the efficacies of powder activated carbon (PAC) and granular activated carbon (GAC) as amendments for the immobilization of volatile compounds in soil. Soil artificially-spiked with chlorobenzenes (CBs) was amended with either PAC or GAC to obtain an application rate of 1%. The results showed that the dissipation and volatilization of CBs from the amended soil significantly decreased compared to the unamended soil. The bioavailabilities of CBs, which is expressed as butanol extraction and earthworm accumulation, were significantly reduced in PAC and GAC amended soils. The lower chlorinated and hence more volatile CBs experienced higher reductions in both dissipation and bioavailability in the amended soils. The GAC and PAC equally immobilized more volatile CBs in soil. Therefore, it could be concluded that along with environmental implication, applying GAC was the more promising approach for the effective immobilization of volatile compounds in soil.

Endocannabinoid hydrolases in avian HD11 macrophages identified by chemoproteomics: inactivation by small molecule inhibitors and pathogen-induced downregulation of their activity.

USDA-ARS?s Scientific Manuscript database

The endocannabinoids (eCBs) are endogenous arachidonoyl-containing lipid mediators with important roles in host defense. Macrophages are first-line defenders of the innate immune system and biosynthesize large amounts of eCBs when activated. The cellular levels of eCBs are controlled by the activiti...

Plasma Screening for Progranulin Mutations in Patients with Progressive Supranuclear Palsy and Corticobasal Syndromes.

PubMed

Galimberti, Daniela; Bertram, Kelly; Formica, Alessandra; Fenoglio, Chiara; Cioffi, Sara M G; Arighi, Andrea; Scarpini, Elio; Colosimo, Carlo

2016-05-04

Progranulin gene (GRN) mutations are characterized by heterogeneous presentations. Corticobasal syndrome (CBS) is often associated with GRN mutations, whereas association with progressive supranuclear palsy syndrome (PSPS) is rare. Plasma progranulin levels were evaluated in 34 patients, including 19 with PSPS, 12 with CBS, and 3 with mixed signs, with the purpose to screen for the presence of causal mutations, associated with low levels. We found undetectable levels in a patient with CBS. Sequencing confirmed the presence of the Thr272fs deletion. Progranulin mutation screening is suggested in cases of CBS, even in the absence of positive family history for dementia and/or movement disorders.

Chromatoid Body Protein TDRD6 Supports Long 3’ UTR Triggered Nonsense Mediated mRNA Decay

PubMed Central

Fanourgakis, Grigorios; Akpinar, Müge; Dahl, Andreas; Jessberger, Rolf

2016-01-01

Chromatoid bodies (CBs) are spermiogenesis-specific organelles of largely unknown function. CBs harbor various RNA species, RNA-associated proteins and proteins of the tudor domain family like TDRD6, which is required for a proper CB architecture. Proteome analysis of purified CBs revealed components of the nonsense-mediated mRNA decay (NMD) machinery including UPF1. TDRD6 is essential for UPF1 localization to CBs, for UPF1-UPF2 and UPF1-MVH interactions. Upon removal of TDRD6, the association of several mRNAs with UPF1 and UPF2 is disturbed, and the long 3’ UTR-stimulated but not the downstream exon-exon junction triggered pathway of NMD is impaired. Reduced association of the long 3’ UTR mRNAs with UPF1 and UPF2 correlates with increased stability and enhanced translational activity. Thus, we identified TDRD6 within CBs as required for mRNA degradation, specifically the extended 3’ UTR-triggered NMD pathway, and provide evidence for the requirement of NMD in spermiogenesis. This function depends on TDRD6-promoted assembly of mRNA and decay enzymes in CBs. PMID:27149095

Optical–Mid-infrared Period–Luminosity Relations for W UMa-type Contact Binaries Based on Gaia DR 1: 8% Distance Accuracy

NASA Astrophysics Data System (ADS)

Chen, Xiaodian; Deng, Licai; de Grijs, Richard; Wang, Shu; Feng, Yuting

2018-06-01

W Ursa Majoris (W UMa)-type contact binary systems (CBs) are useful statistical distance indicators because of their large numbers. Here, we establish (orbital) period–luminosity relations (PLRs) in 12 optical to mid-infrared bands (GBVRIJHK s W1W2W3W4) based on 183 nearby W UMa-type CBs with accurate Tycho–Gaia parallaxes. The 1σ dispersion of the PLRs decreases from optical to near- and mid-infrared wavelengths. The minimum scatter, 0.16 mag, implies that W UMa-type CBs can be used to recover distances to 7% precision. Applying our newly determined PLRs to 19 open clusters containing W UMa-type CBs demonstrates that the PLR and open cluster CB distance scales are mutually consistent to within 1%. Adopting our PLRs as secondary distance indicators, we compiled a catalog of 55,603 CB candidates, of which 80% have distance estimates based on a combination of optical, near-infrared, and mid-infrared photometry. Using Fourier decomposition, 27,318 high-probability W UMa-type CBs were selected. The resulting 8% distance accuracy implies that our sample encompasses the largest number of objects with accurate distances within a local volume with a radius of 3 kpc available to date. The distribution of W UMa-type CBs in the Galaxy suggests that in different environments, the CB luminosity function may be different: larger numbers of brighter (longer-period) W UMa-type CBs are found in younger environments.

Microwave thawing and green tea extract efficiency for the formation of acrylamide throughout the production process of chicken burgers and chicken nuggets.

PubMed

Soncu, Eda Demirok; Kolsarici, Nuray

2017-04-01

Initially, we measured the acrylamide (AA) levels of chicken burgers (CBs) and chicken nuggets (CNs) purchased from fast food restaurants. After the determination of AA in these products, we aimed to investigate whether the use of green tea extract in the covering material, and microwave thawing before frying, mitigated the formation of AA in CBs and CNs during the production process. According to our study, AA concentrations of CBs and CNs purchased from fast food restaurants were in the range of 13.43-118.97 and 32.92-134.90 ng g -1 coating, respectively. In our experiment, AA levels varied between 19.61 and 40.08 ng g -1 coating for CBs and 7.92-49.60 ng g -1 coating for CNs. Green tea extract reduced the AA formation in CBs and CNs at the pan frying and steam oven cooking heat treatment steps (P < 0.05). However, microwave thawing did not affect AA level of CBs and CNs. When the AA levels of commercial CBs and CNs are compared with those produced in our experiment, the use of green tea extract could be a novel, easy and practical application for fast food producers to minimise AA levels in the first two steps of the production without changes to the sensory properties of the final products. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Coastal erosion vs riverline sediment discharge in the Arctic shelfx seas

USGS Publications Warehouse

Rachold, V.; Grigoriev, M.N.; Are, F.E.; Solomon, Sean C.; Reimnitz, E.; Kassens, H.; Antonow, M.

2000-01-01

This article presents a comparison of sediment input by rivers and by coastal erosion into both the Laptev Sea and the Canadian Beaufort Sea (CBS). New data on coastal erosion in the Laptev Sea, which are based on field measurements and remote sensing information and existing data on coastal erosion in the CBS as well as riverine sediment discharge into both the Laptev Sea and the CBS are included. Strong regional differences in the percentages of coastal ero- sion and riverine sediment supply are observed. The CBS is dominated by the riverine sediment discharge (64.45x106 t a-1) mainly of the Mackenzie River. which is the largest single source of sediments in the Arctic. Riverine sediment discharge into the Laptev Sea amounts to 24.10x106 t a-1, more than 70% of which are related to the Lena River. In comparison with the CBS. the Laptev Sea coast on average delivers approximately twice as much sediment mass per kilometer, a result of higher erosion rates due to higher cliffs and seasonal ice melting. In the Laptev Sea sediment input by coastal erosion (58.4x106 t a-1) is therefore more important than in the CBS and the ratio between riverine and coastal sediment input amounts to 0.4. Coastal erosion supplying 5.6x106 t a-1 is less significant for the sediment budget of the CBS where riverine sediment discharge exceeds coastal sediment input by a factor of ca. 10.

The impact of communication barriers on diagnostic confidence and ancillary testing in the emergency department.

PubMed

Garra, Gregory; Albino, Hiram; Chapman, Heather; Singer, Adam J; Thode, Henry C

2010-06-01

Communication barriers (CBs) compromise the diagnostic power of the medical interview and may result in increased reliance on diagnostic tests or incorrect test ordering. The prevalence and degree to which these barriers affect diagnosis, testing, and treatment are unknown. To quantify and characterize CBs encountered in the Emergency Department (ED), and assess the effect of CBs on initial diagnosis and perceived reliance on ancillary testing. This was a prospective survey completed by emergency physicians after initial adult patient encounters. CB severity, diagnostic confidence, and reliance on ancillary testing were quantified on a 100-mm Visual Analog Scale (VAS) from least (0) to most (100). Data were collected on 417 ED patient encounters. CBs were reported in 46%; with a mean severity of 50 mm on a 100-mm VAS with endpoints of "perfect communication and "no communication." Language was the most commonly reported form of CB (28%). More than one CB was identified in 6%. The 100-mm VAS rating of diagnostic confidence was lower in patients with perceived CBs (64 mm) vs. those without CBs (80 mm), p < 0.001. VAS ratings of physician reliance on ancillary testing was higher in patients with perceived CBs (50 mm) vs. patients without a perceived CB (38 mm), p < 0.001. Communication barriers in our ED setting were common, and resulted in lower diagnostic confidence and increased perception that ancillary tests are needed to narrow the diagnosis. Copyright 2010 Elsevier Inc. All rights reserved.

Effectiveness of community-based support for pregnant women living with HIV: a cohort study in South Africa.

PubMed

Fatti, Geoffrey; Shaikh, Najma; Eley, Brian; Grimwood, Ashraf

2016-01-01

Antiretroviral treatment (ART) initiation in HIV-infected pregnant women in sub-Saharan Africa (SSA) remains inadequate, and there is a severe shortage of professional healthcare workers in the region. The effectiveness of community support programmes for HIV-infected pregnant women and their infants in SSA is unclear. This study compared initiation of maternal antiretrovirals and infant outcomes amongst HIV-infected pregnant women and their infants who received and did not receive community-based support (CBS) in a high HIV-prevalence setting in South Africa. A cohort study, including HIV-infected pregnant women and their infants, was conducted at three sentinel surveillance facilities between January 2009 and June 2012, utilising enhanced routine clinical data. Through home visits, CBS workers encouraged uptake of interventions in the ART cascade, provided HIV-related education, ART initiation counselling and psychosocial support. Outcomes were compared using Kaplan-Meier analyses and multivariable Cox and log-binomial regression. Amongst 1105 mother-infant pairs included, 264 (23.9%) received CBS. Amongst women eligible to start ART antenatally, women who received CBS had a reduced risk of not initiating antenatal ART, 5.4% vs. 30.3%; adjusted risk ratio (aRR) = 0.18 (95% CI: 0.08-0.44; P < .0001). Women who received CBS initiated antenatal ART with less delay after the first antenatal visit, median 26 days vs. 39 days; adjusted hazard ratio (aHR) = 1.57 (95% CI: 1.15-2.14; P = .004). Amongst women who initiated antenatal zidovudine (ZDV) to prevent vertical transmission, women who received CBS initiated ZDV with less delay, aHR = 1.52 (95% CI: 1.18-2.01; P = .001). Women who received CBS had a lower risk of stillbirth, 1.5% vs. 5.4%; aRR = 0.24 (95% CI: 0.07-1.00; P = .050). Pregnant women living with HIV who received CBS had improved antenatal triple ART initiation in eligible women, women initiated ART and ZDV with shorter delays, and had a lower risk of stillbirth. CBS is an intervention that shows promise in improving maternal and infant health in high HIV-prevalence settings.

Using synchrotron X-ray microtomography to characterize the pore network of reservoir rocks: A case study on carbonates

NASA Astrophysics Data System (ADS)

Arzilli, F.; Cilona, A.; Mancini, L.; Tondi, E.

2016-09-01

In this work we propose a new methodology to calculate pore connectivity in granular rocks. This method is useful to characterize the pore networks of natural and laboratory compaction bands (CBs), and compare them with the host rock pore network. Data were collected using the synchrotron X-ray microtomography technique and quantitative analyses were carried out using the Pore3D software library. The porosity was calculated from segmented tridimensional images of deformed and pristine rocks. A process of skeletonization of the pore space was used to obtain the number of connected pores within the rock volume. By analyzing the skeletons the differences between natural and laboratory CBs were highlighted. The natural CB has a lower porosity than to the laboratory one. In natural CBs, the grain contacts appear welded, whereas laboratory CBs show irregular pore shape. Moreover, we assessed for the first time how pore connectivity evolves as a function of deformation, documenting the mechanism responsible for pore connectivity drop within the CBs.

Validity and test-retest reliability in assessing current body size with figure drawings in Chinese adolescents.

PubMed

Lo, Wing-Sze; Ho, Sai-Yin; Wong, Bonny Yee-Man; Mak, Kwok-Kei; Lam, Tai-Hing

2011-06-01

The reliability and validity of Stunkard's Figure Rating Scale (FRS) as a measure of current body size (CBS) was established in Western adolescent girls but not in non-Western population. We examined the validity and test-retest reliability of Stunkard's FRS in assessing CBS among Chinese adolescents. Methods. In a school-based survey in Hong Kong, 5666 adolescents (boys: 45.1%; mean age 14.7 years) provided data on self-reported height and weight, CBS, perceived weight status, and health-related quality of life using the Medical Outcomes Study Short-Form version 2 (SF-12v2). Height and weight were also objectively measured. Spearman's correlation was used to assess construct validity, concurrent validity and test-retest reliability. Convergent and discriminant validity were good: CBS correlated strongly with weight and self-reported/measured BMI, but only weakly with SF-12v2. CBS correlated strongly with perceived weight status, showing concurrent validity. Spearman's correlation (r) for CBS was 0.78 for girls and 0.72 for boys indicating good test-retest reliability. Validity and reliability results did not differ significantly between senior and junior grade adolescents. Our findings support the use of Stunkard's FRS to measure body size among Chinese adolescents.

Novel cystathionine β-synthase gene mutations in a Filipino patient with classic homocystinuria.

PubMed

Silao, Catherine Lynn T; Fabella, Terence Diane F; Rama, Kahlil Izza D; Estrada, Sylvia C

2015-10-01

Classic homocystinuria due to cystathionine β-synthase (CBS) deficiency is an autosomal recessive disorder of sulfur metabolism. Clinical manifestations include mental retardation, dislocation of the optic lens (ectopia lentis), skeletal abnormalities and a tendency to thromboembolic episodes. We present the first mutational analysis of CBS in a Filipino patient with classic homocystinuria. Genomic DNA was extracted from peripheral blood collected from a diagnosed Filipino patient with classic homocystinuria. The entire coding region of CBS (17 exons) was amplified using polymerase chain reaction and bidirectionally sequenced using standard protocols. The patient was found to be compound heterozygous for two novel mutations, g.13995G>A [c.982G>A; p.D328K] and g.15860-15868dupGCAGGAGCT [c.1083-1091dupGCAGGAGCT; p. Q362-L364dupQEL]. Four known single-nucleotide polymorphisms (rs234706, rs1801181, rs706208 and rs706209) were also detected in the present patient's CBS. The patient was heterozygous for all the identified alleles. This is the first mutational analysis of CBS done in a Filipino patient with classic homocystinuria who presented with a novel duplication mutation and a novel missense mutation. Homocystinuria due to CBS deficiency is a heterogeneous disorder at the molecular level. © 2015 Japan Pediatric Society.

Blink reflex recovery cycle to differentiate Progressive Supranuclear Palsy from Cortico-basal syndrome.

PubMed

Sciacca, Giorgia; Nicoletti, Alessandra; Mostile, Giovanni; Luca, Antonina; Raciti, Loredana; Dibilio, Valeria; Drago, Filippo; Salomone, Salvatore; Zappia, Mario

2018-05-13

Progressive Supranuclear Palsy (PSP) and Cortico-basal syndrome (CBS) may share similar clinical findings and peculiar tests to distinguish between the two disorders could be useful. We evaluated Blink Reflex (BR) and R2 Blink Reflex Recovery Cycle (R2BRRC), determining diagnostic sensitivity, specificity, positive and negative predictive value of R2BRRC in differentiating PSP from CBS patients. This was a prospective data collection study investigating BR and R2BRRC at interstimulus intervals (ISIs) of 100, 150, 200, 300, 400, 500, 750 ms in 12 PSP patients, 8 CBS patients, and 10 controls. Patients with PSP have earlier recruitment of R2BRRC as compared to patients with CBS (ISI 100: p=0.002; ISI 150: p<0.001; ISI 200: p<0.001; ISI 300: p=0.02) and controls (ISI 100: p<0.001; ISI 150: p<0.001; ISI 200: p<0.001; ISI 300: p=0.004). The presence of an early recovery of the R2 differentiated PSP from CBS with specificity and sensitivity of 87.5% and 91.7% respectively. R2BRRC curve might be considered a useful tool in differentiating PSP from CBS patients. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Starmerella camargoi f.a., sp. nov., Starmerella ilheusensis f.a., sp. nov., Starmerella litoralis f.a., sp. nov., Starmerella opuntiae f.a., sp. nov., Starmerella roubikii f.a., sp. nov. and Starmerella vitae f.a., sp. nov., isolated from flowers and bees, and transfer of related Candida species to the genus Starmerella as new combinations.

PubMed

Santos, Ana Raquel O; Leon, Marina P; Barros, Katharina O; Freitas, Larissa F D; Hughes, Alice F S; Morais, Paula B; Lachance, Marc-André; Rosa, Carlos A

2018-04-01

Six novel yeast species, Starmerella camargoi f.a., sp. nov., Starmerella ilheusensis f.a., sp. nov., Starmerella litoralis f.a., Starmerella opuntiae f.a., sp. nov., sp. nov., Starmerella roubikii f.a., sp. nov. and Starmerella vitae f.a, sp. nov. are proposed to accommodate 19 isolates recovered from ephemeral flowers or bees in Brazil, Costa Rica and Belize. Sequence analysis of the ITS-5.8S region (when available) and the D1/D2 domains of the large subunit of the rRNA gene showed that the six novel yeasts are phylogenetically related to several species of the Starmerella clade. The type strains are Starmerella camargoi f.a., sp. nov. UFMG-CM-Y595 T (=CBS 14130 T ; Mycobank number MB 822640), Starmerella ilheusensis f.a., sp. nov. UFMG-CM-Y596 T (=CBS CBS14131 T ; MB 822641), Starmerella litoralis f.a., sp. nov. UFMG-CM-Y603 T (=CBS14104 T ; MB 822642), Starmerella opuntiae f.a., sp. nov. UFMG-CM-Y286 T (=CBS 13466 T ; MB 822643), Starmerella roubikii f.a., sp. nov. UWOPS 01-191.1 (=CBS 15148; MB 822645) and Starmerella vitae f.a., sp. nov. UWOPS 00-107.2 (=CBS 15147 T ; MB 822646). In addition, 25 species currently assigned to the genus Candida are reassigned formally to the genus Starmerella.

Yamadazyma kitorensis f.a., sp. nov. and Zygoascus biomembranicola f.a., sp. nov., novel yeasts from the stone chamber interior of the Kitora tumulus, and five novel combinations in Yamadazyma and Zygoascus for species of Candida.

PubMed

Nagatsuka, Yuka; Ninomiya, Shinya; Kiyuna, Tomohiko; Kigawa, Rika; Sano, Chie; Sugiyama, Junta

2016-04-01

Analysis of D1/D2 large-subunit (LSU) rRNA gene sequences predicted that 17 yeast isolates, mainly from viscous gels (biofilms) taken from the stone chamber interior of the Kitora tumulus in Nara, Japan, were placed in the Yamadazyma and Zygoascus clades. Polyphasic characterization, including morphological, physiological and chemotaxonomic characteristics, multigene sequence divergence and DNA-DNA hybridization, strongly suggested the assignment of one novel species to each of the clades; these are Yamadazyma kitorensis f.a., sp. nov., with the type strain JCM 31005T (ex-type CBS 14158T=isolate K8617-6-8T), and Zygoascus biomembranicola f.a., sp. nov., with the type strain JCM 31007T (ex-type CBS 14157T=isolate K61208-2-11T). Furthermore, the transfer of five known species of the genus Candida as novel combinations to the genera Yamadazyma and Zygoascus is proposed; these are Yamadazyma olivae f.a., comb. nov. (type strain CBS 11171T=ATCC MYA-4568T), Yamadazyma tumulicola f.a., comb. nov. (type strain JCM 15403T=ex-type CBS 10917T=isolate T6517-9-5T), Yamadazyma takamatsuzukensis f.a., comb. nov. (type strain JCM 15410T=CBS 10916T = isolate T4922-1-1T), Zygoascus polysorbophila f.a., comb. nov. (type strain NRRL Y-27161T=CBS 7317T) and Zygoascus bituminiphila f.a., comb. nov. (type strain CBS 8813T=MUCL 41424T).

Hallucinatory experiences in visually impaired individuals: Charles Bonnet syndrome - implications for research and clinical practice.

PubMed

Jurišić, Darija; Sesar, Irena; Ćavar, Ivan; Sesar, Antonio; Živković, Maja; Ćurković, Marko

2018-06-01

Charles Bonnet syndrome (CBS) refers to visual hallucinations that occur in individuals with preserved cognitive functions associated with visual impairment. This article reviews occurence of visual hallucinations in subjects with CBS by journals published in English in the Pubmed database in the period 1992-2018. Criteria for selection of appropriate papers were sufficient information and perspicuous view on pathogenesis, epidemiology, clinical presentation and treatment possibilities of CBS. Most commonly, visual hallucinations in patients with CBS are complex, repetitive and stereotyped. Such individuals have preserved insight that those percepts are not real, and there is an absence of secondary explanatory delusions and hallucinations within other modalities. Seeing as the aforementioned percepts do not share all the characteristics of hallucinations, it remains unresolved how they should be referred to. Terms as release hallucinations, one that is reflecting its underlying pathogenesis, or confabulatory hallucinatory experiences have been proposed. Moreover, CBS has also been referred to as phantom vision syndrome and may occur in any ophthalmological disease. It is not particularly connected with loss of function along any level of the visual pathway. Although this syndrome is mostly associated with age-related macular degeneration, glaucoma and cataract, it could be related to almost any other ophthalmological conditions. The incidence of CBS alongside with mostly other ocular pathology is rising as population is ageing. Nonetheless, CBS remains commonly underreported, under recognized and/or misrecognized. Albeit the treatment recommendations and guidelines are not yet fully established, it is important to raise awareness of this specific and distinct condition, which inevitably implicates many differential diagnostic deliberations.

Charles Bonnet Syndrome: Evidence for a Generative Model in the Cortex?

PubMed Central

Reichert, David P.; Seriès, Peggy; Storkey, Amos J.

2013-01-01

Several theories propose that the cortex implements an internal model to explain, predict, and learn about sensory data, but the nature of this model is unclear. One condition that could be highly informative here is Charles Bonnet syndrome (CBS), where loss of vision leads to complex, vivid visual hallucinations of objects, people, and whole scenes. CBS could be taken as indication that there is a generative model in the brain, specifically one that can synthesise rich, consistent visual representations even in the absence of actual visual input. The processes that lead to CBS are poorly understood. Here, we argue that a model recently introduced in machine learning, the deep Boltzmann machine (DBM), could capture the relevant aspects of (hypothetical) generative processing in the cortex. The DBM carries both the semantics of a probabilistic generative model and of a neural network. The latter allows us to model a concrete neural mechanism that could underlie CBS, namely, homeostatic regulation of neuronal activity. We show that homeostatic plasticity could serve to make the learnt internal model robust against e.g. degradation of sensory input, but overcompensate in the case of CBS, leading to hallucinations. We demonstrate how a wide range of features of CBS can be explained in the model and suggest a potential role for the neuromodulator acetylcholine. This work constitutes the first concrete computational model of CBS and the first application of the DBM as a model in computational neuroscience. Our results lend further credence to the hypothesis of a generative model in the brain. PMID:23874177

Role of CBS and Bateman Domains in Phosphorylation-Dependent Regulation of a CLC Anion Channel.

PubMed

Yamada, Toshiki; Krzeminski, Mickael; Bozoky, Zoltan; Forman-Kay, Julie D; Strange, Kevin

2016-11-01

Eukaryotic CLC anion channels and transporters are homodimeric proteins composed of multiple α-helical membrane domains and large cytoplasmic C-termini containing two cystathionine-β-synthase domains (CBS1 and CBS2) that dimerize to form a Bateman domain. The Bateman domains of adjacent CLC subunits interact to form a Bateman domain dimer. The functions of CLC CBS and Bateman domains are poorly understood. We utilized the Caenorhabditis elegans CLC-1/2/Ka/Kb anion channel homolog CLH-3b to characterize the regulatory roles of CLC cytoplasmic domains. CLH-3b activity is reduced by phosphorylation or deletion of a 14-amino-acid activation domain (AD) located on the linker connecting CBS1 and CBS2. We demonstrate here that phosphorylation-dependent reductions in channel activity require an intact Bateman domain dimer and concomitant phosphorylation or deletion of both ADs. Regulation of a CLH-3b AD deletion mutant is reconstituted by intracellular perfusion with recombinant 14-amino-acid AD peptides. The sulfhydryl reactive reagent 2-(trimethylammonium)ethyl methanethiosulfonate bromide (MTSET) alters in a phosphorylation-dependent manner the activity of channels containing single cysteine residues that are engineered into the short intracellular loop connecting membrane α-helices H and I (H-I loop), the AD, CBS1, and CBS2. In contrast, MTSET has no effect on channels in which cysteine residues are engineered into intracellular regions that are dispensable for regulation. These studies together with our previous work suggest that binding and unbinding of the AD to the Bateman domain dimer induces conformational changes that are transduced to channel membrane domains via the H-I loop. Our findings provide new, to our knowledge, insights into the roles of CLC Bateman domains and the structure-function relationships that govern the regulation of CLC protein activity by diverse ligands and signaling pathways. Copyright © 2016 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Characterization of the secreted cathepsin B cysteine proteases family of the carcinogenic liver fluke Clonorchis sinensis.

PubMed

Chen, Wenjun; Wang, Xiaoyun; Lv, Xiaoli; Tian, Yanli; Xu, Yanquan; Mao, Qiang; Shang, Mei; Li, Xuerong; Huang, Yan; Yu, Xinbing

2014-09-01

Clonorchis sinensis excretory/secretory products (ESP) have gained high attentions because of their potential to be vaccine candidates and drug targets in C. sinensis prevention. In this study, we extensively profiled the characteristics of four C. sinensis cathepsin B cysteine proteases (CsCB1, CsCB2, CsCB3, and CsCB4). Bioinformatics analysis showed all CsCBs contained signal peptides at the N-terminal. Functional domains and residues were found in CsCB sequences. We expressed four CsCBs and profiled immune responses followed by vaccine trials. Recombinant CsCBs could induce high IgG titers, indicating high immunogenicity of CsCB family. Additionally, ELISA results showed that both IgG1 and IgG2a levels apparently increased post-immunization with all four CsCBs, showing that combined Th1/Th2 immune responses were triggered by CsCB family. Both Real-time polymerase chain reaction (RT-PCR) and Western blotting confirmed that four CsCBs have distinct expression patterns in C. sinensis life stages. More importantly, we validated our hypothesis that CsCBs were C. sinensis excretory/secretory products. CsCBs could be recognized by C. sinensis-infected sera throughout the infection period, indicating that secreted CsCBs are immune triggers during C. sinensis infection. The protective effect was assessed by comparing the worm burden and egg per gram (EPG) between CsCB group and control group, showing that worm burden (P < 0.01) and EPG (P < 0.01) in CsCB2 and CsCB3 groups were significantly lower than in control group. In conclusion, we profiled secreted cathepsin B cysteine proteases family for the first time and demonstrated that all CsCB family were C. sinensis excretory/secretory products that may regulate host immune responses.

Heterozygous carriers of classical homocystinuria tend to have higher fasting serum homocysteine concentrations than non-carriers in the presence of folate deficiency.

PubMed

Lu, Yung-Hsiu; Cheng, Li-Mei; Huang, Yu-Hsiu; Lo, Ming-Yu; Wu, Tina Jui-Ting; Lin, Hsiang-Yu; Hsu, Ting-Rong; Niu, Dau-Ming

2015-12-01

Many studies have reported that serum total homocysteine (tHcy) levels in cystathionine-beta-synthase (CBS) carriers are usually normal and only elevated after a methionine load. However, the amount of methionine required for a loading test is non-physiological and is never reached with regular feeding. Therefore, CBS carriers do not seem to be at an increased risk of cardiovascular diseases. However, the risk of cardiovascular diseases of CBS carriers with folate deficiency has not been studied. We recently found an extraordinarily high carrier rate (1/7.78) of a novel CBS mutation (p.D47E, c.T141A) in an Austronesian Taiwanese Tao tribe who live in a geographic area with folate deficiency. We evaluated if the CBS carriers tend to have higher fasting serum tHcy concentrations than non-carriers in presence of folate deficiency. The serum tHcy and folate levels before and after folate replacement were measured in 48 adult Tao carriers, 40 age-matched Tao non-carriers and 40 age-matched Han Taiwanese controls. The serum tHcy level of the Tao CBS carriers (17.9 ± 3.8 μmol/l) was significantly higher than in Tao non-carriers (15.7 ± 3.5 μmol/l; p < 0.008) and Taiwanese controls (11.8 ± 2.9 μmol/l; p < 0.001). Furthermore, a high prevalence of folate deficiency in the Tao compared with the Taiwanese controls (4.9 ± 1.8 ng/ml vs. 10.6 ± 5.5 ng/ml; p < 0.001) was also noted. Of note, the difference in tHcy levels between the carriers and non-carriers was eliminated by folate supplementation. (carriers:13.65 ± 2.13 μmol/l; non-carriers:12.39 ± 3.25 μmol/l, p = 0.321). CBS carriers tend to have a higher tHcy level in the presence of folate deficiency than non-carriers. Although many reports have indicated that CBS carriers are not associated with cardiovascular disease, the risk for CBS carriers with folate deficiency has not been well studied. Owing to a significantly elevated level of fasting tHcy without methionine loading, it is important to evaluate the risk of cardiovascular disease in CBS carriers with folate deficiency. Copyright © 2014 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

A Practical Note on Transferring Ideas and Methods from Consultancy Practice to the MPA Classroom: A Personal Account from a Danish Case Study

ERIC Educational Resources Information Center

Nielsen, J. C. Ry; Quinn, Brid

2016-01-01

At the lead author's home institution--Copenhagen Business School (CBS)--the combination of theory and practice is seen as very important in teaching. Research-based teaching is the slogan. In this respect, CBS has the same ambition as other universities. But it seems as if CBS has an advantage at the master's level, because students come with a…

Candida oceani sp. nov., a novel yeast isolated from a Mid-Atlantic Ridge hydrothermal vent (-2300 meters).

PubMed

Burgaud, Gaëtan; Arzur, Danielle; Sampaio, José Paulo; Barbier, Georges

2011-06-01

A novel species in the genus Candida was obtained from deep-sea hydrothermal fields on the Mid-Atlantic Ridge. Strains Mo39, MARY089 and CBS 5307, respectively, isolated from an unidentified deep-sea coral collected near Rainbow hydrothermal vent, from water samples near Menez Gwen hydrothermal field and from the stomach of a marine fish are considered as a novel taxon. Sequence similarities in the D1/D2 region of the 26S rRNA gene indicated that strains Mo39, MARY089 and CBS 5307 have for closest neighbors Candida spencermartinsiae, Candida taylorii, Candida atmosphaerica and Candida atlantica. The strains, respectively, differ from C. spencermartinsiae, C. taylorii, C. atmosphaerica andCandida atlantica by 4, 4.3, 4.3 and 4.7% in the D1/D2 domain. Strains Mo39, MARY089 and CBS 5307 were differentiated from others by differences in the ability to assimilate D: -Gluconate and in the ability to grow at relatively high temperature. Only strain Mo39 displays an optimal growth at 3% sea salts, indicating that this strain is clearly adapted to live in marine conditions. Sequence similarities between strains Mo39, MARY089 and CBS 5307 and related species and differences in the ability to utilize specific carbon compounds revealed that these strains represent a hitherto unknown species. Sexual reproduction was not observed in strains Mo39, MARY089 and CBS 5307. An anamorphic name Candida oceani sp. nov. is proposed for the type strain Mo39(T) (= CBS 11857(T) = DSM 23777(T)) and the two other strains MARY089 and CBS 5307. To our knowledge, this is the first description of a micro-eukaryotic organism including a strain isolated from a deep-sea coral near a hydrothermal ecosystem.

Crystallographic and mutational analyses of cystathionine β-synthase in the H2 S-synthetic gene cluster in Lactobacillus plantarum.

PubMed

Matoba, Yasuyuki; Yoshida, Tomoki; Izuhara-Kihara, Hisae; Noda, Masafumi; Sugiyama, Masanori

2017-04-01

Cystathionine β-synthase (CBS) catalyzes the formation of l-cystathionine from l-serine and l-homocysteine. The resulting l-cystathionine is decomposed into l-cysteine, ammonia, and α-ketobutylic acid by cystathionine γ-lyase (CGL). This reverse transsulfuration pathway, which is catalyzed by both enzymes, mainly occurs in eukaryotic cells. The eukaryotic CBS and CGL have recently been recognized as major physiological enzymes for the generation of hydrogen sulfide (H 2 S). In some bacteria, including the plant-derived lactic acid bacterium Lactobacillus plantarum, the CBS- and CGL-encoding genes form a cluster in their genomes. Inactivation of these enzymes has been reported to suppress H 2 S production in bacteria; interestingly, it has been shown that H 2 S suppression increases their susceptibility to various antibiotics. In the present study, we characterized the enzymatic properties of the L. plantarum CBS, whose amino acid sequence displays a similarity with those of O-acetyl-l-serine sulfhydrylase (OASS) that catalyzes the generation of l-cysteine from O-acetyl-l-serine (l-OAS) and H 2 S. The L. plantarum CBS shows l-OAS- and l-cysteine-dependent CBS activities together with OASS activity. Especially, it catalyzes the formation of H 2 S in the presence of l-cysteine and l-homocysteine, together with the formation of l-cystathionine. The high affinity toward l-cysteine as a first substrate and tendency to use l-homocysteine as a second substrate might be associated with its enzymatic ability to generate H 2 S. Crystallographic and mutational analyses of CBS indicate that the Ala70 and Glu223 residues at the substrate binding pocket are important for the H 2 S-generating activity. © 2017 The Protein Society.

D-Xylose fermentation, xylitol production and xylanase activities by seven new species of Sugiyamaella.

PubMed

Sena, Letícia M F; Morais, Camila G; Lopes, Mariana R; Santos, Renata O; Uetanabaro, Ana P T; Morais, Paula B; Vital, Marcos J S; de Morais, Marcos A; Lachance, Marc-André; Rosa, Carlos A

2017-01-01

Sixteen yeast isolates identified as belonging to the genus Sugiyamaella were studied in relation to D-xylose fermentation, xylitol production, and xylanase activities. The yeasts were recovered from rotting wood and sugarcane bagasse samples in different Brazilian regions. Sequence analyses of the internal transcribed spacer (ITS) region and the D1/D2 domains of large subunit rRNA gene showed that these isolates belong to seven new species. The species are described here as Sugiyamaella ayubii f.a., sp. nov. (UFMG-CM-Y607 T  = CBS 14108 T ), Sugiyamaella bahiana f.a., sp. nov. (UFMG-CM-Y304 T  = CBS 13474 T ), Sugiyamaella bonitensis f.a., sp. nov. (UFMG-CM-Y608 T  = CBS 14270 T ), Sugiyamaella carassensis f.a., sp. nov. (UFMG-CM-Y606 T  = CBS 14107 T ), Sugiyamaella ligni f.a., sp. nov. (UFMG-CM-Y295 T  = CBS 13482 T ), Sugiyamaella valenteae f.a., sp. nov. (UFMG-CM-Y609 T  = CBS 14109 T ) and Sugiyamaella xylolytica f.a., sp. nov. (UFMG-CM-Y348 T  = CBS 13493 T ). Strains of the described species S. boreocaroliniensis, S. lignohabitans, S. novakii and S. xylanicola, isolated from rotting wood of Brazilian ecosystems, were also compared for traits relevant to xylose metabolism. S. valenteae sp. nov., S. xylolytica sp. nov., S. bahiana sp. nov., S. bonitensis sp. nov., S. boreocarolinensis, S. lignohabitans and S. xylanicola were able to ferment D-xylose to ethanol. Xylitol production was observed for all Sugiyamaella species studied, except for S. ayubii sp. nov. All species studied showed xylanolytic activity, with S. xylanicola, S. lignohabitans and S. valenteae sp. nov. having the highest values. Our results suggest these Sugiyamaella species have good potential for biotechnological applications.

Efficacy and gastrointestinal tolerability of ML3403, a selective inhibitor of p38 MAP kinase and CBS-3595, a dual inhibitor of p38 MAP kinase and phosphodiesterase 4 in CFA-induced arthritis in rats.

PubMed

Koch, Diana A; Silva, Rodrigo B M; de Souza, Alessandra H; Leite, Carlos E; Nicoletti, Natália F; Campos, Maria M; Laufer, Stefan; Morrone, Fernanda B

2014-03-01

Mitogen-activated protein kinase (MAPK) p38 inhibitors have entered the clinical phase, although many of them have failed due to high toxicity and lack of efficacy. In the present study we compared the effects of the selective p38 inhibitor ML3403 and the dual p38-PDE4 inhibitor CBS-3595, on inflammatory and nociceptive parameters in a model of polyarthritis in rats. Male Wistar rats (180-200 g) were used for the complete Freund's adjuvant (CFA)-induced arthritis model and they were evaluated at 14-21 days. We also analysed the effects of these pharmacological tools on liver and gastrointestinal toxicity and on cytokine levels. Repeated CBS-3595 (3 mg/kg) or ML3403 (10 mg/kg) administration produced significant anti-inflammatory actions in the chronic arthritis model induced by CFA. CBS-3595 and ML3403 treatment also markedly reduced the production of the proinflammatory cytokine IL-6 in the paw tissue, whereas it widely increased the levels of the anti-inflammatory cytokine IL-10. Moreover, CBS-3595 produced partial anti-allodynic effects in the CFA model at 4 and 8 days after treatment. Notably, ML3403 and CBS-3595 did not show marked signs of hepatoxicity, as supported by unaltered histological observations in the liver sections. Finally, both compounds were safe in the gastrointestinal tract, according to evaluation of intestinal biopsies. CBS-3595 displayed a superior profile regarding its anti-inflammatory effects. Thus p38 MAPK/PDE4 blocking might well constitute a relevant strategy for the treatment of RA.

Vascular complications of cystathionine β-synthase deficiency: future directions for homocysteine-to-hydrogen sulfide research

PubMed Central

Beard, Richard S.

2011-01-01

Homocysteine (Hcy), a cardiovascular and neurovascular disease risk factor, is converted to hydrogen sulfide (H2S) through the transsulfuration pathway. H2S has attracted considerable attention in recent years for many positive effects on vascular health and homeostasis. Cystathionine β-synthase (CBS) is the first, and rate-limiting, enzyme in the transsulfuration pathway. Mutations in the CBS gene decrease enzymatic activity, which increases the plasma Hcy concentration, a condition called hyperhomocysteinemia (HHcy). Animal models of CBS deficiency have provided invaluable insights into the pathological effects of transsulfuration impairment and of both mild and severe HHcy. However, studies have also highlighted the complexity of HHcy and the need to explore the specific details of Hcy metabolism in addition to Hcy levels per se. There has been a relative paucity of work addressing the dysfunctional H2S production in CBS deficiency that may contribute to, or even create, HHcy-associated pathologies. Experiments using CBS knockout mice, both homozygous (−/−) and heterozygous (+/−), have provided 15 years of new knowledge and are the focus of this review. These murine models present the opportunity to study a specific mechanism for HHcy that matches one of the etiologies in many human patients. Therefore, the goal of this review was to integrate and highlight the critical information gained thus far from models of CBS deficiency and draw attention to critical gaps in knowledge, with particular emphasis on the modulation of H2S metabolism. We include findings from human and animal studies to identify important opportunities for future investigation that should be aimed at generating new basic and clinical understanding of the role of CBS and transsulfuration in cardiovascular and neurovascular disease. PMID:20971760

Important casual association of carotid body and glossopharyngeal nerve and lung following experimental subarachnoid hemorrhage in rabbits. First report.

PubMed

Yolas, Coskun; Kanat, Ayhan; Aydin, Mehmet Dumlu; Turkmenoglu, Osman Nuri; Gundogdu, Cemal

2014-01-15

The glossopharyngeal nerves (GPNs) and carotid bodies (CBs) have an important role in the continuation of the cerebral autoregulation and cardiorespiratory functions. The relationship between degenerative injury of CB and the GPN in subarachnoid hemorrhage (SAH) was studied. Twenty rabbits were included in this study. Five of them (n=5) were used as control group. The remaining animals (n=15) were exposed to experimental SAH. In the six animals of the SAH group, severe signs of illness were observed, and these six animals were killed in the first week after SAH. Others animals (n=9) were followed for 20 days and then sacrificed. GPNs and CBs were examined and, the live and degenerated GPN axon number, and of CB neuron numbers were stereologically estimated. The mean number of live neurons in CBs was 4206.67±148.35 and live axons of GPNs were 1211.66±14.29 in the animals of the control group. The number of degenerated neurons of CBs was 2065±110.27 and the number of degenerated axons of GPNs was 530.83±43.48 in early killed animals with SAH. The number of degenerated neurons of CBs and the number of degenerated axons of GPNs were found as 1013.89±4184 and 2270.5±134.38 in the living animals with SAH, respectively. High number of degenerated axons of GPN and neurons of CBs of the early killed animals suggest that the mortality in early SAH might be due to GPNs injury secondary to compression of their axons or supplying vessels by the probably herniated brainstem, and secondary denervation injury of CBs, and lung. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

A Model for the Stop Planning and Timetables of Customized Buses

PubMed Central

Yang, Yang

2017-01-01

Customized buses (CBs) are a new mode of public transportation and an important part of diversified public transportation, providing advanced, attractive and user-led service. The operational activity of a CB is planned by aggregating space–time demand and similar passenger travel demands. Based on an analysis of domestic and international research and the current development of CBs in China and considering passenger travel data, this paper studies the problems associated with the operation of CBs, such as stop selection, line planning and timetables, and establishes a model for the stop planning and timetables of CBs. The improved immune genetic algorithm (IIGA) is used to solve the model with regard to the following: 1) multiple population design and transport operator design, 2) memory library design, 3) mutation probability design and crossover probability design, and 4) the fitness calculation of the gene segment. Finally, a real-world example in Beijing is calculated, and the model and solution results are verified and analyzed. The results illustrate that the IIGA solves the model and is superior to the basic genetic algorithm in terms of the number of passengers, travel time, average passenger travel time, average passenger arrival time ahead of schedule and total line revenue. This study covers the key issues involving operational systems of CBs, combines theoretical research and empirical analysis, and provides a theoretical foundation for the planning and operation of CBs. PMID:28056041

A Model for the Stop Planning and Timetables of Customized Buses.

PubMed

Ma, Jihui; Zhao, Yanqing; Yang, Yang; Liu, Tao; Guan, Wei; Wang, Jiao; Song, Cuiying

2017-01-01

Customized buses (CBs) are a new mode of public transportation and an important part of diversified public transportation, providing advanced, attractive and user-led service. The operational activity of a CB is planned by aggregating space-time demand and similar passenger travel demands. Based on an analysis of domestic and international research and the current development of CBs in China and considering passenger travel data, this paper studies the problems associated with the operation of CBs, such as stop selection, line planning and timetables, and establishes a model for the stop planning and timetables of CBs. The improved immune genetic algorithm (IIGA) is used to solve the model with regard to the following: 1) multiple population design and transport operator design, 2) memory library design, 3) mutation probability design and crossover probability design, and 4) the fitness calculation of the gene segment. Finally, a real-world example in Beijing is calculated, and the model and solution results are verified and analyzed. The results illustrate that the IIGA solves the model and is superior to the basic genetic algorithm in terms of the number of passengers, travel time, average passenger travel time, average passenger arrival time ahead of schedule and total line revenue. This study covers the key issues involving operational systems of CBs, combines theoretical research and empirical analysis, and provides a theoretical foundation for the planning and operation of CBs.

Driving towards malaria elimination in Botswana by 2018: progress on case-based surveillance, 2013–2014

PubMed Central

Edwards, J.; Namboze, J.; Butt, W.; Moakofhi, K.; Obopile, M.; Manzi, M.; Takarinda, K. C.; Zachariah, R.; Owiti, P.; Oumer, N.; Mosweunyane, T.

2018-01-01

Background: Reliable information reporting systems ensure that all malaria cases are tested, treated and tracked to avoid further transmission. Botswana aimed to eliminate malaria by 2018, and surveillance is key. This study focused on assessing the uptake of the new malaria case-based surveillance (CBS) system introduced in 2012, which captures information on malaria cases reported in the Integrated Disease Surveillance and Response (IDSR) system. Methods: This was a retrospective descriptive study based on routine data focusing on Ngami, Chobe and Okavango, three high-risk districts in Botswana. Aggregated data variables were extracted from the IDSR and compared with data from the CBS. Results: The IDSR reported 456 malaria cases in 2013 and 1346 in 2014, of which respectively only 305 and 884 were reported by the CBS. The CBS reported 34% fewer cases than the IDSR system, indicating substantial differences between the two systems. The key malaria indicators with the greatest variability among the districts included in the study were case identification number and date of diagnosis. Conclusion: The IDSR and CBS systems are essential for malaria elimination, as shown by the significant gaps in reporting between the two systems. These findings highlight the need for further investigation into these discrepancies. Strengthening the CBS system will help to reach the objective of malaria elimination in Botswana. PMID:29713590

The role of surface electrostatics on the stability, function and regulation of human cystathionine β-synthase, a complex multidomain and oligomeric protein.

PubMed

Pey, Angel L; Majtan, Tomas; Kraus, Jan P

2014-09-01

Human cystathionine β-synthase (hCBS) is a key enzyme of sulfur amino acid metabolism, controlling the commitment of homocysteine to the transsulfuration pathway and antioxidant defense. Mutations in hCBS cause inherited homocystinuria (HCU), a rare inborn error of metabolism characterized by accumulation of toxic homocysteine in blood and urine. hCBS is a complex multidomain and oligomeric protein whose activity and stability are independently regulated by the binding of S-adenosyl-methionine (SAM) to two different types of sites at its C-terminal regulatory domain. Here we study the role of surface electrostatics on the complex regulation and stability of hCBS using biophysical and biochemical procedures. We show that the kinetic stability of the catalytic and regulatory domains is significantly affected by the modulation of surface electrostatics through noticeable structural and energetic changes along their denaturation pathways. We also show that surface electrostatics strongly affect SAM binding properties to those sites responsible for either enzyme activation or kinetic stabilization. Our results provide new insight into the regulation of hCBS activity and stability in vivo with implications for understanding HCU as a conformational disease. We also lend experimental support to the role of electrostatic interactions in the recently proposed binding modes of SAM leading to hCBS activation and kinetic stabilization. Copyright © 2014 Elsevier B.V. All rights reserved.

Transcultural validation of the ALS-CBS Cognitive Section for the Brazilian population.

PubMed

Branco, Lucas M T; Zanao, Tamires; De Rezende, Thiago J; Casseb, Raphael F; Balthazar, Marcio F; Woolley, Susan C; França, Marcondes C

2017-02-01

Cognitive decline (CD) is common but often under-recognized in ALS due to the scarcity of adequate cognitive screening methods. In this scenario, the Amyotrophic Lateral Sclerosis Cognitive Behavioural Screen (ALS-CBS) is the most investigated instrument and presents high sensitivity to identify CD. Currently, there are no validated cognitive screening tools for ALS patients in the Brazilian population and little is known about the frequency of ALS related CD in the country. We assessed the accuracy of the Brazilian Portuguese version of ALS-CBS Cognitive Section (ALS-CBS-Br) for classifying the cognitive status of Brazilian patients compared to a standard neuropsychological battery, and estimated the prevalence of CD in the Brazilian ALS population. Among 73 initially recruited ALS patients, 49 were included. Twenty-four patients were excluded due to severe motor disability, FTD diagnosis or non-acceptance. Ten healthy controls were also included. Ten ALS patients (20%) were diagnosed with executive dysfunction (ALSci) based on the battery results. ALS-CBS-Br scores were significantly lower in the ALSci group (p < 0.001). The scale accuracy in detecting executive dysfunction was 0.906. Optimal cut-off score was 10/20 (specificity 0.872 and sensitivity 0.900). In conclusion, the ALS-CBS-Br may facilitate the recognition of CD in routine clinical care and complement future studies in our population.

THE ENDOCANNABINOID SYSTEM MODULATES THE VALENCE OF THE EMOTION ASSOCIATED TO FOOD INGESTION

PubMed Central

Méndez-Díaz, Mónica; Rueda-Orozco, Pavel Ernesto; Ruiz-Contreras, Alejandra Evelyn; Prospéro-García, O.

2010-01-01

Endocannabinoids (eCBs) are mediators of the homeostatic and hedonic systems that modulate food ingestion. Hence, eCBs, by regulating the hedonic system, may be modulating the valence of the emotion associated to food ingestion (positive: pleasant, or negative: unpleasant). Our first goal was to demonstrate that palatable food induces conditioned place preference (CPP), hence a positive valence emotion. Additionally, we analyzed if this CPP is blocked by AM251, inducing a negative valence emotion, meaning avoiding the otherwise pursued compartment. The second goal was to demonstrate that CPP induced by regular food would be strengthened by the simultaneous administration of anandamide or oleamide and if such CPP is blocked by AM251. Finally, we tested the capacity of eCBs (without food) to induce CPP. Our results indicate that rats readily developed CPP to palatable food, which was blocked by AM251. The CPP induced by regular food was strengthened by eCBs and blocked by AM251. Finally, oleamide, unlike anandamide, induced CPP. These results showed that eCBs mediate the positive valence (CPP) of the emotion associated to food ingestion. It was also observed that the blockade of the CB1 receptor causes a loss of correlation between food and CPP (negative valence: avoidance). These data further support the role of eCBs as regulators of the hedonic value of food. PMID:21182571

Fluoxetine Facilitates Fear Extinction Through Amygdala Endocannabinoids

PubMed Central

Gunduz-Cinar, Ozge; Flynn, Shaun; Brockway, Emma; Kaugars, Katherine; Baldi, Rita; Ramikie, Teniel S; Cinar, Resat; Kunos, George; Patel, Sachin; Holmes, Andrew

2016-01-01

Pharmacologically elevating brain endocannabinoids (eCBs) share anxiolytic and fear extinction-facilitating properties with classical therapeutics, including the selective serotonin reuptake inhibitor, fluoxetine. There are also known functional interactions between the eCB and serotonin systems and preliminary evidence that antidepressants cause alterations in brain eCBs. However, the potential role of eCBs in mediating the facilitatory effects of fluoxetine on fear extinction has not been established. Here, to test for a possible mechanistic contribution of eCBs to fluoxetine's proextinction effects, we integrated biochemical, electrophysiological, pharmacological, and behavioral techniques, using the extinction-impaired 129S1/Sv1mJ mouse strain. Chronic fluoxetine treatment produced a significant and selective increase in levels of anandamide in the BLA, and an associated decrease in activity of the anandamide-catabolizing enzyme, fatty acid amide hydrolase. Slice electrophysiological recordings showed that fluoxetine-induced increases in anandamide were associated with the amplification of eCB-mediated tonic constraint of inhibitory, but not excitatory, transmission in the BLA. Behaviorally, chronic fluoxetine facilitated extinction retrieval in a manner that was prevented by systemic or BLA-specific blockade of CB1 receptors. In contrast to fluoxetine, citalopram treatment did not increase BLA eCBs or facilitate extinction. Taken together, these findings reveal a novel, obligatory role for amygdala eCBs in the proextinction effects of a major pharmacotherapy for trauma- and stressor-related disorders and anxiety disorders. PMID:26514583

Fluoxetine Facilitates Fear Extinction Through Amygdala Endocannabinoids.

PubMed

Gunduz-Cinar, Ozge; Flynn, Shaun; Brockway, Emma; Kaugars, Katherine; Baldi, Rita; Ramikie, Teniel S; Cinar, Resat; Kunos, George; Patel, Sachin; Holmes, Andrew

2016-05-01

Pharmacologically elevating brain endocannabinoids (eCBs) share anxiolytic and fear extinction-facilitating properties with classical therapeutics, including the selective serotonin reuptake inhibitor, fluoxetine. There are also known functional interactions between the eCB and serotonin systems and preliminary evidence that antidepressants cause alterations in brain eCBs. However, the potential role of eCBs in mediating the facilitatory effects of fluoxetine on fear extinction has not been established. Here, to test for a possible mechanistic contribution of eCBs to fluoxetine's proextinction effects, we integrated biochemical, electrophysiological, pharmacological, and behavioral techniques, using the extinction-impaired 129S1/Sv1mJ mouse strain. Chronic fluoxetine treatment produced a significant and selective increase in levels of anandamide in the BLA, and an associated decrease in activity of the anandamide-catabolizing enzyme, fatty acid amide hydrolase. Slice electrophysiological recordings showed that fluoxetine-induced increases in anandamide were associated with the amplification of eCB-mediated tonic constraint of inhibitory, but not excitatory, transmission in the BLA. Behaviorally, chronic fluoxetine facilitated extinction retrieval in a manner that was prevented by systemic or BLA-specific blockade of CB1 receptors. In contrast to fluoxetine, citalopram treatment did not increase BLA eCBs or facilitate extinction. Taken together, these findings reveal a novel, obligatory role for amygdala eCBs in the proextinction effects of a major pharmacotherapy for trauma- and stressor-related disorders and anxiety disorders.

Driving towards malaria elimination in Botswana by 2018: progress on case-based surveillance, 2013-2014.

PubMed

Motlaleng, M; Edwards, J; Namboze, J; Butt, W; Moakofhi, K; Obopile, M; Manzi, M; Takarinda, K C; Zachariah, R; Owiti, P; Oumer, N; Mosweunyane, T

2018-04-25

Background: Reliable information reporting systems ensure that all malaria cases are tested, treated and tracked to avoid further transmission. Botswana aimed to eliminate malaria by 2018, and surveillance is key. This study focused on assessing the uptake of the new malaria case-based surveillance (CBS) system introduced in 2012, which captures information on malaria cases reported in the Integrated Disease Surveillance and Response (IDSR) system. Methods: This was a retrospective descriptive study based on routine data focusing on Ngami, Chobe and Okavango, three high-risk districts in Botswana. Aggregated data variables were extracted from the IDSR and compared with data from the CBS. Results: The IDSR reported 456 malaria cases in 2013 and 1346 in 2014, of which respectively only 305 and 884 were reported by the CBS. The CBS reported 34% fewer cases than the IDSR system, indicating substantial differences between the two systems. The key malaria indicators with the greatest variability among the districts included in the study were case identification number and date of diagnosis. Conclusion: The IDSR and CBS systems are essential for malaria elimination, as shown by the significant gaps in reporting between the two systems. These findings highlight the need for further investigation into these discrepancies. Strengthening the CBS system will help to reach the objective of malaria elimination in Botswana.

Pumping RNA: nuclear bodybuilding along the RNP pipeline.

PubMed

Matera, A Gregory; Shpargel, Karl B

2006-06-01

Cajal bodies (CBs) are nuclear subdomains involved in the biogenesis of several classes of small ribonucleoproteins (RNPs). A number of recent advances highlight progress in the understanding of the organization and dynamics of CB components. For example, a class of small Cajal body-specific (sca) RNPs has been discovered. Localization of scaRNPs to CBs was shown to depend on a conserved RNA motif. Intriguingly, this motif is also present in mammalian telomerase RNA and the evidence suggests that assembly of the active form of telomerase RNP occurs in and around CBs during S phase. Important steps in the assembly and modification of spliceosomal RNPs have also been shown to take place in CBs. Additional experiments have revealed the existence of kinetically distinct subclasses of CB components. Finally, the recent identification of novel markers for CBs in both Drosophila and Arabidopsis not only lays to rest questions about the evolutionary conservation of these nuclear suborganelles, but also should enable forward genetic screens for the identification of new components and pathways involved in their assembly, maintenance and function.

[Culture-bound syndromes: pertinence as a diagnostic category].

PubMed

Perez, S; Junod, A; Pilard, M

2000-01-01

Culture-bound syndromes (CBS) are supposedly confined to one specific cultural areas. These syndromes were first studied by western anthropologists and psychiatrists working overseas, and later by practitioners treating patients from societies with traditional customs and values. The latest edition of the American Psychiatry Association classification (DSM IV) includes an annex on CBS. This report gives a concise background of the process that led to the inclusion of this annex. Then using Koro (a sudden and intense fear that the genitals organs will recede into the body) as an example, a number psychopathological parallels are drawn between CBS and classic manifestations of individual and mass hysteria. The pertinence of individualizing the CBS in the psychiatric nosography including the epistemologic implications is analyzed with reference to the concepts of the French and American Schools of Anthropology. Since attitudes toward mental illness are culturally determined and subject to variation in time and space, we feel that this debate should be placed within the context of a general dialectic between etic (universality) and emic (cultural specificity) rather than a controversy on the need for an annex on CBS in the DSM IV.

Container-based sanitation: assessing costs and effectiveness of excreta management in Cap Haitien, Haiti

PubMed Central

Tilmans, Sebastien; Russel, Kory; Sklar, Rachel; Page, Leah; Kramer, Sasha

2015-01-01

Container-based sanitation (CBS) – in which wastes are captured in sealable containers that are then transported to treatment facilities – is an alternative sanitation option in urban areas where on-site sanitation and sewerage are infeasible. This paper presents the results of a pilot household CBS service in Cap Haitien, Haiti. We quantify the excreta generated weekly in a dense urban slum,(1) the proportion safely removed via container-based public and household toilets, and the costs associated with these systems. The CBS service yielded an approximately 3.5-fold decrease in the unmanaged share of faeces produced, and nearly eliminated the reported use of open defecation and “flying toilets” among service recipients. The costs of this pilot small-scale service were higher than those of large-scale waterborne sewerage, but economies of scale have the potential to reduce CBS costs over time. The paper concludes with a discussion of planning and policy implications of incorporating CBS into the menu of sanitation options for rapidly growing cities. PMID:26097288

Cajal-body formation correlates with differential coilin phosphorylation in primary and transformed cell lines.

PubMed

Hearst, Scoty M; Gilder, Andrew S; Negi, Sandeep S; Davis, Misty D; George, Eric M; Whittom, Angela A; Toyota, Cory G; Husedzinovic, Alma; Gruss, Oliver J; Hebert, Michael D

2009-06-01

Cajal bodies (CBs) are nuclear structures that are thought to have diverse functions, including small nuclear ribonucleoprotein (snRNP) biogenesis. The phosphorylation status of coilin, the CB marker protein, might impact CB formation. We hypothesize that primary cells, which lack CBs, contain different phosphoisoforms of coilin compared with that found in transformed cells, which have CBs. Localization, self-association and fluorescence recovery after photobleaching (FRAP) studies on coilin phosphomutants all suggest this modification impacts the function of coilin and may thus contribute towards CB formation. Two-dimensional gel electrophoresis demonstrates that coilin is hyperphosphorylated in primary cells compared with transformed cells. mRNA levels of the nuclear phosphatase PPM1G are significantly reduced in primary cells and expression of PPM1G in primary cells induces CBs. Additionally, PPM1G can dephosphorylate coilin in vitro. Surprisingly, however, expression of green fluorescent protein alone is sufficient to form CBs in primary cells. Taken together, our data support a model whereby coilin is the target of an uncharacterized signal transduction cascade that responds to the increased transcription and snRNP demands found in transformed cells.

The mass spectrum of the white dwarfs in cataclysmic binaries - Supplementary computations

NASA Astrophysics Data System (ADS)

Ritter, H.; Ozkan, M. T.

1986-10-01

Numerical computations supplementing those of Ritter and Burkert (1986) for the study of observational selection in favor of massive white dwarfs among cataclysmic binaries (CBs) are presented. In particular the contribution of CBs beyond the period minimum and the influence of the inclination and of limb-darkening of the accretion disk are investigated. It is found that: (1) the main conclusions of Ritter and Burkert remain unchanged; (2) neither the inclusion of CBs containing a black-dwarf secondary nor the variation of the inclination or limb-darkening change the selection significantly; (3) in a magnitude-limited sample, about 22 percent of the ultra-short-period CBs contain a degenerate secondary; (4) the mean inclination of the accretion disk in a magnitude-limited sample is always close to 60 deg; (5) the fraction of eclipsing systems is of order 10-15 percent at m(v) = 10.0; (6) the mean inclination and the fraction of eclipsing systems increases with the limiting magnitude; and (7) the intrinsic space density of CBs is n(CB) approximately .0001-.0002/cu pc.

Endurance and failure characteristics of modified Vasco X-2, CBS 600 and AISI 9310 spur gears. [aircraft construction materials

NASA Technical Reports Server (NTRS)

Townsend, D. P.; Zaretsky, E. V.

1980-01-01

Gear endurance tests and rolling-element fatigue tests were conducted to compare the performance of spur gears made from AISI 9310, CBS 600 and modified Vasco X-2 and to compare the pitting fatigue lives of these three materials. Gears manufactured from CBS 600 exhibited lives longer than those manufactured from AISI 9310. However, rolling-element fatigue tests resulted in statistically equivalent lives. Modified Vasco X-2 exhibited statistically equivalent lives to AISI 9310. CBS 600 and modified Vasco X-2 gears exhibited the potential of tooth fracture occurring at a tooth surface fatigue pit. Case carburization of all gear surfaces for the modified Vasco X-2 gears results in fracture at the tips of the gears.

An exploratory study on low-concentration hexavalent chromium adsorption by Fe(III)-cross-linked chitosan beads

PubMed Central

Zhang, Yuanjing; Qian, Jin; Xin, Xu; Hu, Sihai; Zhang, Shuai; Wei, Jianguo

2017-01-01

In this study, Fe(III)-cross-linked chitosan beads (Fe(III)-CBs) were synthesized and employed to explore the characteristics and primary mechanism of their hexavalent chromium (Cr(VI)) adsorption under low concentration Cr(VI) (less than 20.0 mg l−1) and a pH range from 2.0 to 8.0. Batch tests were conducted to determine the Cr(VI) adsorption capacity and kinetics, and the effects of pH and temperature on the adsorption under low concentration Cr(VI) and a pH range from 2.0 to 8.0. Scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy were employed to explore the characteristics of Fe(III)-CBs and their Cr(VI) adsorption mechanisms. The results show that, unlike the adsorption of other absorbents, the Cr(VI) adsorption was efficient in a wide pH range from 2.0 to 6.0, and well described by the pseudo-first-order model and the Langmuir–Freundlich isotherm model. The capacity of Cr(VI) adsorption by Fe(III)-CBs was as high as 166.3 mg g−1 under temperature 25°C and pH 6.0. The desorption test was also carried out by 0.1 mol l−1 NaOH solution for Fe(III)-CBs regeneration. It was found that Fe(III)-CBs could be re-used for five adsorption–desorption cycles without significant decrease in Cr(VI) adsorption capacity. Ion exchange was confirmed between functional groups (i.e. amino group) and Cr(VI) anions (i.e. CrO42−). The amino-like functional groups played a key role in Cr(VI) distribution on the Fe(III)-CBs surface; Cr(VI) adsorbed on Fe(III)-CBs was partially reduced to Cr(III) with alcoholic group served as electron donor, and then formed another rate-limiting factor. So, Fe(III)-CBs has a good prospect in purifying low concentration Cr(VI) water with a pH range from 2.0 to 6.0. PMID:29291084

The endocannabinoid system modulates the valence of the emotion associated to food ingestion.

PubMed

Méndez-Díaz, Mónica; Rueda-Orozco, Pavel Ernesto; Ruiz-Contreras, Alejandra Evelyn; Prospéro-García, Oscar

2012-07-01

Endocannabinoids (eCBs) are mediators of the homeostatic and hedonic systems that modulate food ingestion. Hence, eCBs, by regulating the hedonic system, may be modulating the valence of the emotion associated to food ingestion (positive: pleasant or negative: unpleasant). Our first goal was to demonstrate that palatable food induces conditioned place preference (CPP), hence a positive-valence emotion. Additionally, we analyzed if this CPP is blocked by AM251, inducing a negative valence emotion, meaning avoiding the otherwise pursued compartment. The second goal was to demonstrate that CPP induced by regular food would be strengthened by the simultaneous administration of anandamide or oleamide, and if such, CPP is blocked by AM251. Finally, we tested the capacity of eCBs (without food) to induce CPP. Our results indicate that rats readily developed CPP to palatable food, which was blocked by AM251. The CPP induced by regular food was strengthened by eCBs and blocked by AM251. Finally, oleamide, unlike anandamide, induced CPP. These results showed that eCBs mediate the positive valence (CPP) of the emotion associated to food ingestion. It was also observed that the blockade of the CB1 receptor causes a loss of correlation between food and CPP (negative valence: avoidance). These data further support the role of eCBs as regulators of the hedonic value of food. © 2010 The Authors. Addiction Biology © 2010 Society for the Study of Addiction.

Rhodotorula bloemfonteinensis sp. nov., Rhodotorula eucalyptica sp. nov., Rhodotorula orientis sp. nov. and Rhodotorula pini sp. nov., yeasts isolated from monoterpene-rich environments.

PubMed

Pohl, Carolina H; Smit, Martha S; Albertyn, Jacobus

2011-09-01

Recent rDNA sequencing of 25 isolates from a previous study, during which limonene-utilizing yeasts were isolated from monoterpene-rich environments by using 1,4-disubstituted cyclohexanes as sole carbon sources, led to the identification of four hitherto unknown Rhodotorula species. Analyses of the 26S rDNA D1/D2 region as well as the internal transcribed spacer (ITS) domain indicated that two isolates (CBS 8499(T) and CBS 10736) were identical and were closely related to Rhodotorula cycloclastica, a previously described limonene-utilizing yeast. These novel isolates differed from known yeast species and could be distinguished from R. cycloclastica by standard physiological tests. The other three isolates represent three novel Rhodotorula species, closely related to Sporobolomyces magnisporus. These three species could also be distinguished from other Rhodotorula species by standard physiological tests. Based on these results, we suggest that the new isolates represent novel species, for which the names Rhodotorula eucalyptica sp. nov. (type strain CBS 8499(T)  = NRRL Y-48408(T)), Rhodotorula pini sp. nov. (type strain CBS 10735(T)  = NRRL Y-48410(T)), Rhodotorula bloemfonteinensis sp. nov. (type strain CBS 8598(T)  = NRRL Y-48407(T)) and Rhodotorula orientis sp. nov. (type strain CBS 8594(T)  = NRRL Y-48719(T)) are proposed. R. eucalyptica and R. pini can also utilize limonene.

Biomechanical comparison of 3.0 mm headless compression screw and 3.5 mm cortical bone screw in a canine humeral condylar fracture model.

PubMed

Gonsalves, Mishka N; Jankovits, Daniel A; Huber, Michael L; Strom, Adam M; Garcia, Tanya C; Stover, Susan M

2016-09-20

To compare the biomechanical properties of simulated humeral condylar fractures reduced with one of two screw fixation methods: 3.0 mm headless compression screw (HCS) or 3.5 mm cortical bone screw (CBS) placed in lag fashion. Bilateral humeri were collected from nine canine cadavers. Standardized osteotomies were stabilized with 3.0 mm HCS in one limb and 3.5 mm CBS in the contralateral limb. Condylar fragments were loaded to walk, trot, and failure loads while measuring construct properties and condylar fragment motion. The 3.5 mm CBS-stabilized constructs were 36% stiffer than 3.0 mm HCS-stabilized constructs, but differences were not apparent in quality of fracture reduction nor in yield loads, which exceeded expected physiological loads during rehabilitation. Small residual fragment displacements were not different between CBS and HCS screws. Small fragment rotation was not significantly different between screws, but was weakly correlated with moment arm length (R² = 0.25). A CBS screw placed in lag fashion provides stiffer fixation than an HCS screw, although both screws provide similar anatomical reduction and yield strength to condylar fracture fixation in adult canine humeri.

Cajal-body formation correlates with differential coilin phosphorylation in primary and transformed cell lines

PubMed Central

Hearst, Scoty M.; Gilder, Andrew S.; Negi, Sandeep S.; Davis, Misty D.; George, Eric M.; Whittom, Angela A.; Toyota, Cory G.; Husedzinovic, Alma; Gruss, Oliver J.; Hebert, Michael D.

2009-01-01

Summary Cajal bodies (CBs) are nuclear structures that are thought to have diverse functions, including small nuclear ribonucleoprotein (snRNP) biogenesis. The phosphorylation status of coilin, the CB marker protein, might impact CB formation. We hypothesize that primary cells, which lack CBs, contain different phosphoisoforms of coilin compared with that found in transformed cells, which have CBs. Localization, self-association and fluorescence recovery after photobleaching (FRAP) studies on coilin phosphomutants all suggest this modification impacts the function of coilin and may thus contribute towards CB formation. Two-dimensional gel electrophoresis demonstrates that coilin is hyperphosphorylated in primary cells compared with transformed cells. mRNA levels of the nuclear phosphatase PPM1G are significantly reduced in primary cells and expression of PPM1G in primary cells induces CBs. Additionally, PPM1G can dephosphorylate coilin in vitro. Surprisingly, however, expression of green fluorescent protein alone is sufficient to form CBs in primary cells. Taken together, our data support a model whereby coilin is the target of an uncharacterized signal transduction cascade that responds to the increased transcription and snRNP demands found in transformed cells. PMID:19435804

Density functional Theory Based Generalized Effective Fragment Potential Method (Postprint)

DTIC Science & Technology

2014-07-01

is acceptable for other applications) leads to induced dipole moments within 10−6 to 10−7 au of the precise values . Thus, the applied field of 10−4...noncovalent interactions. The water-benzene clusters17 and WATER2711 reference values were also ob- tained at the CCSD(T)/CBS level, except for the clusters...with n = 20,42 where MP2/CBS was used. The n-alkane dimers18 benchmark values were CCSD(T)/CBS for ethane to butane and a linear extrapolation method

A comparative study of shear bond strength between metal and ceramic brackets and artificially aged composite restorations using different surface treatments.

PubMed

Eslamian, Ladan; Borzabadi-Farahani, Ali; Mousavi, Nasim; Ghasemi, Amir

2012-10-01

This in vitro study evaluated the shear bond strength (SBS) between ceramic brackets (CBs) and resin composite restorations (RCRs) prepared using different surface treatments. The findings were also compared with a similar study that used stainless steel brackets (SSBs). Forty-five premolars were restored with a nano-hybrid composite resin (Tetric EvoCeram) and randomly assigned to three surface treatment groups: group 1, 5 per cent hydrofluoric acid (HF); group 2, air abrasion (50 μm alumina particles); and group 3, diamond bur. Specimens were bonded with CBs (Fascination) and exposed to thermo-cycling (500 cycles). The shear force at a crosshead speed of 1 mm/minute was transmitted to brackets. The adhesive remnant index (ARIs) scores were recorded after bracket failure. The analysis of SBS variance (P < 0.01) and chi-square test of ARIs scores (P < 0.01) revealed significant differences among three groups tested. The SBS in group 3 (mean: 26.34 ± 4.76 MPa) and group 2 (mean: 26.68 ± 5.93 MPa) was significantly higher than group 1 (mean: 16.25 ± 5.42 MPa). The SBS was significantly higher in CBs (mean: 23.09 ± 7.19 MPa) compared to SSBs (mean: 15.56 ± 5.13 MPa). High ARIs (100 per cent) occurred in SSBs treated with a diamond bur, whereas CBs primarily failed at the resin-adhesive interface (P < 0.01). In two-thirds of the specimens (SSBs or CBs), no adhesive was left on the restoration after HF conditioning. The ARIs profile of CBs and SSBs that received surface treatments with air abrasion were similar (P > 0.05) and bond failure occurred mainly in adhesive-bracket base and resin-adhesive interfaces. The diamond bur surface treatment is recommended as a safe and cost-effective method of bonding CBs to RCRs.

Augmented H2S production via cystathionine-beta-synthase upregulation plays a role in pregnancy-associated uterine vasodilation.

PubMed

Sheibani, Lili; Lechuga, Thomas J; Zhang, Honghai; Hameed, Afshan; Wing, Deborah A; Kumar, Sathish; Rosenfeld, Charles R; Chen, Dong-Bao

2017-03-01

Endogenous hydrogen sulfide (H2S) synthesized via metabolizing L-cysteine by cystathionine-beta-synthase (CBS) and cystathionine-gamma-lyase (CSE) is a potent vasodilator and angiogenic factor. The objectives of this study were to determine if human uterine artery (UA) H2S production increases with augmented expression and/or activity of CBS and/or CSE during the menstrual cycle and pregnancy and whether exogenous H2S dilates UA. Uterine arteries from nonpregnant (NP) premenopausal proliferative (pPRM) and secretory (sPRM) phases of the menstrual cycle and pregnant (P) women were studied. H2S production was measured by the methylene blue assay. CBS and CSE mRNAs were assessed by quantitative real-time PCR, and proteins were assessed by immunoblotting and semiquantitative immunofluorescence microscopy. Effects of H2S on rat UA relaxation were determined by wire myography ex vivo. H2S production was greater in NP pPRM and P than NP sPRM UAs and inhibited by the specific CBS but not CSE inhibitor. CBS but not CSE mRNA and protein were greater in NP pPRM and P than NP sPRM UAs. CBS protein was localized to endothelium and smooth muscle and its levels were in a quantitative order of P >NP UAs of pPRM>sPRM. CSE protein was localized in UA endothelium and smooth muscle with no difference among groups. A H2S donor relaxed P > NP UAs but not mesentery artery. Thus, human UA H2S production is augmented with endothelium and smooth muscle CBS upregulation, contributing to UA vasodilation in the estrogen-dominant physiological states in the proliferative phase of the menstrual cycle and pregnancy. © The Authors 2017. Published by Oxford University Press on behalf of Society for the Study of Reproduction. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Resistance of Loblolly Pine Sources to Fusiform Rust in Field Progeny Tests

Treesearch

H.R. Powers; E.G. Kuhlman

1987-01-01

Results of concentrated basidiospore spray (CBS) inoculations correlated well with field infection. Generally, the CBS system correctly classified resistant and susceptible sources, but it classed seven sources with field resistance as susceptible.

Two new species of the genus Candida in the Zygoascus clade, Candida lundiana sp. nov. and Candida suthepensis sp. nov., isolated from raw honey in Thailand.

PubMed

Saksinchai, Sujinan; Suzuki, Motofumi; Lumyong, Saisamorn; Ohkuma, Moriya; Chantawannakul, Panuwan

2012-03-01

During a survey of yeasts associated with raw honey collected in Thailand, two strains of the Zygoascus clade were isolated from the Asian cavity-nesting honeybee Apis cerana and the stingless bee Homotrigona fimbriata. Phylogeny based on 26S rDNA D1/D2 sequences placed these yeasts as members of a clade including Candida bituminiphila, Candida patagonica and Candida polysorbophila. The strains of the two novel species, CBS 12271(T) and CBS 12270(T), respectively, could be unquestionably distinguished from their relatives by rDNA sequences and other taxonomic characteristics. Therefore, the novel anamorphic species, Candida lundiana sp. nov. (type strain CBS 12271(T) = JCM 16823(T)) and Candida suthepensis sp. nov. (type strain CBS 12270(T) = JCM 16822(T)) are described.

Charles Bonnet syndrome: three cases in the emergency department.

PubMed

Frost, Elizabeth J; Mottley, J Lawrence; Edlow, Jonathan A

2012-05-01

Charles Bonnet Syndrome (CBS) is a cause of visual hallucinations in elderly patients that is often unrecognized by emergency physicians and has a relatively benign course. As the population ages, it is likely that the number of cases of CBS will increase (and thus, the numbers of those who present to an Emergency Department [ED] will be increasing). The case reports presented in this article will facilitate the recognition of CBS by the emergency physician. We describe 3 patients who presented to one ED for visual disturbances and were diagnosed with CBS in a 4-month time period. Recognition of this unusual but stereotypical cause of visual disturbances facilitates an accurate diagnosis, and spares patients the time and expense of blood testing, imaging, and consultations. If emergency physicians begin to recognize this benign entity, we can provide improved (and safer) patient care with appropriate ED interventions. Copyright © 2012 Elsevier Inc. All rights reserved.

Charles Bonnet Syndrome in a Patient With Right Medial Occipital Lobe Infarction: Epileptic or Deafferentation Phenomenon?

PubMed

Kumral, Emre; Uluakay, Arzu; Dönmez, İlknur

2015-07-01

Charles Bonnet syndrome (CBS) is an uncommon disorder characterized by complex and recurrent visual hallucinations in patients with visual pathway pathologic defects. To describe a patient who experienced complex visual hallucinations following infarction in the right occipital lobe and epileptic seizure who was diagnosed as having CBS. A 65-year-old man presented acute ischemic stroke caused by artery to artery embolism involving the right occipital lobe. Following ischemic stroke, complex visual hallucinations in the left visual field not associated with loss of consciousness or delusion developed in the patient. Hallucinations persisted for >1 month and during hallucination, no electrographic seizures were recorded through 24 hours of videoelectroencephalographic monitoring. CBS may develop in a patient with occipital lobe infarction following an embolic event. CBS associated with medial occipital lobe infarction and epilepsy may coexist and reflects the abnormal functioning of an integrated neuronal network.

Compulsive buying: relationship with body mass index.

PubMed

Sansone, Randy A; Chang, Joy; Jewell, Bryan; Marion, Brandee E

2013-01-01

Compulsive buying has historically been associated with various self-regulatory disturbances, including eating pathology (e.g., binge eating). Therefore, a relationship between scores on a measure of compulsive buying, the Compulsive Buying Scale (CBS), and body mass index (BMI) in adulthood was hypothesized. Using a self-report survey methodology in a cross-sectional consecutive sample of convenience of 373 obstetrics/gynecology patients, correlations between CBS scores and BMI, both generally and with regard to race were examined. A modest general correlation between CBS scores and BMI (r = 0.17, P < 0.01) was found. However, when these data were examined by race, CBS scores and BMI were significantly related among Caucasian women (r = 0.25, P < 0.01), but not in African American women (r = 0.04, P = n.s.). Findings indicate that compulsive buying is associated with increasing BMI in adulthood, particularly among Caucasian women. Copyright © 2013 The Obesity Society.

Progression of brain atrophy in PSP and CBS over 6 months and 1 year.

PubMed

Dutt, Shubir; Binney, Richard J; Heuer, Hilary W; Luong, Phi; Attygalle, Suneth; Bhatt, Priyanka; Marx, Gabe A; Elofson, Jonathan; Tartaglia, Maria C; Litvan, Irene; McGinnis, Scott M; Dickerson, Bradford C; Kornak, John; Waltzman, Dana; Voltarelli, Lisa; Schuff, Norbert; Rabinovici, Gil D; Kramer, Joel H; Jack, Clifford R; Miller, Bruce L; Rosen, Howard J; Boxer, Adam L

2016-11-08

To examine the utility and reliability of volumetric MRI in measuring disease progression in the 4 repeat tauopathies, progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS), to support clinical development of new tau-directed therapeutic agents. Six- and 12-month changes in regional MRI volumes and PSP Rating Scale scores were examined in 55 patients with PSP and 33 patients with CBS (78% amyloid PET negative) compared to 30 normal controls from a multicenter natural history study. Longitudinal voxel-based morphometric analyses identified patterns of volume loss, and region-of-interest analyses examined rates of volume loss in brainstem (midbrain, pons, superior cerebellar peduncle), cortical, and subcortical regions based on previously validated atlases. Results were compared to those in a replication cohort of 226 patients with PSP with MRI data from the AL-108-231 clinical trial. Patients with CBS exhibited greater baseline atrophy and greater longitudinal atrophy rates in cortical and basal ganglia regions than patients with PSP; however, midbrain and pontine atrophy rates were similar. Voxel-wise analyses showed distinct patterns of regional longitudinal atrophy in each group as compared to normal controls. The midbrain/pons volumetric ratio differed between diagnoses but remained stable over time. In both patient groups, brainstem atrophy rates were correlated with disease progression measured using the PSP Rating Scale. Volume loss is quantifiable over a period of 6 months in CBS and PSP. Future clinical trials may be able to combine CBS and PSP to measure therapeutic effects. © 2016 American Academy of Neurology.

Molecular testing guidelines for lung adenocarcinoma: Utility of cell blocks and concordance between fine-needle aspiration cytology and histology samples

PubMed Central

Heymann, Jonas J.; Bulman, William A.; Maxfield, Roger A.; Powell, Charles A.; Halmos, Balazs; Sonett, Joshua; Beaubier, Nike T.; Crapanzano, John P.; Mansukhani, Mahesh M.; Saqi, Anjali

2014-01-01

Background: Lung cancer is a leading cause of mortality, and patients often present at a late stage. More recently, advances in screening, diagnosing, and treating lung cancer have been made. For instance, greater numbers of minimally invasive procedures are being performed, and identification of lung adenocarcinoma driver mutations has led to the implementation of targeted therapies. Advances in molecular techniques enable use of scant tissue, including cytology specimens. In addition, per recently published consensus guidelines, cytology-derived cell blocks (CBs) are preferred over direct smears. Yet, limited comparison of molecular testing of fine-needle aspiration (FNA) CBs and corresponding histology specimens has been performed. This study aimed to establish concordance of epidermal growth factor receptor (EGFR) and Kirsten rat sarcoma (KRAS) virus homolog testing between FNA CBs and histology samples from the same patients. Materials and Methods: Patients for whom molecular testing for EGFR or KRAS was performed on both FNA CBs and histology samples containing lung adenocarcinoma were identified retrospectively. Following microdissection, when necessary, concordance of EGFR and KRAS molecular testing results between FNA CBs and histology samples was evaluated. Results: EGFR and/or KRAS testing was performed on samples obtained from 26 patients. Concordant results were obtained for all EGFR (22/22) and KRAS (17/17) mutation analyses performed. Conclusions: Identification of mutations in lung adenocarcinomas affects clinical decision-making, and it is important that results from small samples be accurate. This study demonstrates that molecular testing on cytology CBs is as sensitive and specific as that on histology. PMID:24987443

Fusarium MLST database

USDA-ARS?s Scientific Manuscript database

The CBS-KNAW Fungal Biodiversity Centre’s Fusarium MLST website (http://www.cbs.knaw.nl/Fusarium), and the corresponding Fusarium-ID site hosted at the Pennsylvania State University (http://isolate.fusariumdb.org; Geiser et al. 2004, Park et al. 2010) were constructed to facilitate identification of...

Mapping cis-Regulatory Domains in the Human Genome UsingMulti-Species Conservation of Synteny

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ahituv, Nadav; Prabhakar, Shyam; Poulin, Francis

2005-06-13

Our inability to associate distant regulatory elements with the genes that they regulate has largely precluded their examination for sequence alterations contributing to human disease. One major obstacle is the large genomic space surrounding targeted genes in which such elements could potentially reside. In order to delineate gene regulatory boundaries we used whole-genome human-mouse-chicken (HMC) and human-mouse-frog (HMF) multiple alignments to compile conserved blocks of synteny (CBS), under the hypothesis that these blocks have been kept intact throughout evolution at least in part by the requirement of regulatory elements to stay linked to the genes that they regulate. A totalmore » of 2,116 and 1,942 CBS>200 kb were assembled for HMC and HMF respectively, encompassing 1.53 and 0.86 Gb of human sequence. To support the existence of complex long-range regulatory domains within these CBS we analyzed the prevalence and distribution of chromosomal aberrations leading to position effects (disruption of a genes regulatory environment), observing a clear bias not only for mapping onto CBS but also for longer CBS size. Our results provide a genome wide data set characterizing the regulatory domains of genes and the conserved regulatory elements within them.« less

Cannabinoids disrupt memory encoding by functionally isolating hippocampal CA1 from CA3.

PubMed

Sandler, Roman A; Fetterhoff, Dustin; Hampson, Robert E; Deadwyler, Sam A; Marmarelis, Vasilis Z

2017-07-01

Much of the research on cannabinoids (CBs) has focused on their effects at the molecular and synaptic level. However, the effects of CBs on the dynamics of neural circuits remains poorly understood. This study aims to disentangle the effects of CBs on the functional dynamics of the hippocampal Schaffer collateral synapse by using data-driven nonparametric modeling. Multi-unit activity was recorded from rats doing an working memory task in control sessions and under the influence of exogenously administered tetrahydrocannabinol (THC), the primary CB found in marijuana. It was found that THC left firing rate unaltered and only slightly reduced theta oscillations. Multivariate autoregressive models, estimated from spontaneous spiking activity, were then used to describe the dynamical transformation from CA3 to CA1. They revealed that THC served to functionally isolate CA1 from CA3 by reducing feedforward excitation and theta information flow. The functional isolation was compensated by increased feedback excitation within CA1, thus leading to unaltered firing rates. Finally, both of these effects were shown to be correlated with memory impairments in the working memory task. By elucidating the circuit mechanisms of CBs, these results help close the gap in knowledge between the cellular and behavioral effects of CBs.

Cannabinoids disrupt memory encoding by functionally isolating hippocampal CA1 from CA3

PubMed Central

Fetterhoff, Dustin; Hampson, Robert E.; Deadwyler, Sam A.; Marmarelis, Vasilis Z.

2017-01-01

Much of the research on cannabinoids (CBs) has focused on their effects at the molecular and synaptic level. However, the effects of CBs on the dynamics of neural circuits remains poorly understood. This study aims to disentangle the effects of CBs on the functional dynamics of the hippocampal Schaffer collateral synapse by using data-driven nonparametric modeling. Multi-unit activity was recorded from rats doing an working memory task in control sessions and under the influence of exogenously administered tetrahydrocannabinol (THC), the primary CB found in marijuana. It was found that THC left firing rate unaltered and only slightly reduced theta oscillations. Multivariate autoregressive models, estimated from spontaneous spiking activity, were then used to describe the dynamical transformation from CA3 to CA1. They revealed that THC served to functionally isolate CA1 from CA3 by reducing feedforward excitation and theta information flow. The functional isolation was compensated by increased feedback excitation within CA1, thus leading to unaltered firing rates. Finally, both of these effects were shown to be correlated with memory impairments in the working memory task. By elucidating the circuit mechanisms of CBs, these results help close the gap in knowledge between the cellular and behavioral effects of CBs. PMID:28686594

Association between Hcy levels and the CBS844ins68 and MTHFR C677T polymorphisms with essential hypertension.

PubMed

Cai, Weijuan; Yin, Liang; Yang, Fang; Zhang, Lei; Cheng, Jiang

2014-11-01

The aim of the present study was to investigate the association between the homocysteine (Hcy) levels and polymorphisms of the CBS844ins68 and MTHFR C677T genes in essential hypertension (EH). The effects of the MTHFR C677T and CBS844ins68 haploid genotypes and the combined genotypes on EH and levels of Hcy were further explored. The polymorphisms of CBS844ins68 and MTHFR C677T genes in 200 EH and 200 normal tensive (NT) patients were detected using polymerase chain reaction-restriction fragment length polymorphism and analysis of the distribution of genotypes. An automated biochemical analyzer was used to measure the plasma Hcy levels and the clinical biochemistry data. The plasma Hcy levels in EH were significantly higher than those of the NT group (P<0.05). There were no significant differences (P>0.05) between males and females. Two genotypes, deletion/deletion (DD) and deletion/insertion (DI), of the CBS844ins68 polymorphism were found in two groups with no clear differences in two genotypes and allele frequency distribution (P>0.05). There were significant differences in the three genotype frequencies (χ 2 =6.658, χ 2 =4.410, P<0.05) for MTHFR C677T locus genotypes CC, CT and TT. The Hcy levels in genotypes DD and DI had no significant differences (P>0.05) and the CT and TT types were significantly higher compared to the CC genotype (P<0.05). The CC/DD combined genotype in the two groups was significantly different (P<0.05), and the odds ratio (OR), 0.569 showed that the CC/DD genotype may be a protective factor of hypertension. In the two groups, the Hcy levels for combined genotypes CC/DD, CT/DD, TT/DD and TT/DI were significantly different (P<0.05). The SHEsis software analysis linkage disequilibrium coefficient=0.216, indicates that there is probably a weak linkage for MTHFR C677T and CBS844ins68 . Haplotype analysis suggested that the C-D haplotype was negatively correlated with EH (OR, 0.727) and that there was a positive correlation between T-D haplotype and EH (OR, 1.376). MTHFR C677T and CBS844ins68 polymorphisms were present in the populations studied and the CBS844ins68 homozygous mutation was not present. Therefore, there is a correlation between the polymorphisms of the MTHFR C677T gene and EH, and allele T may be one of the predisposing factors. MTHFR C677T and CBS844ins68 may exist with a certain linkage and the T-D haplotype may be a risk factor for EH.

Association between Hcy levels and the CBS844ins68 and MTHFR C677T polymorphisms with essential hypertension

PubMed Central

CAI, WEIJUAN; YIN, LIANG; YANG, FANG; ZHANG, LEI; CHENG, JIANG

2014-01-01

The aim of the present study was to investigate the association between the homocysteine (Hcy) levels and polymorphisms of the CBS844ins68 and MTHFR C677T genes in essential hypertension (EH). The effects of the MTHFR C677T and CBS844ins68 haploid genotypes and the combined genotypes on EH and levels of Hcy were further explored. The polymorphisms of CBS844ins68 and MTHFR C677T genes in 200 EH and 200 normal tensive (NT) patients were detected using polymerase chain reaction-restriction fragment length polymorphism and analysis of the distribution of genotypes. An automated biochemical analyzer was used to measure the plasma Hcy levels and the clinical biochemistry data. The plasma Hcy levels in EH were significantly higher than those of the NT group (P<0.05). There were no significant differences (P>0.05) between males and females. Two genotypes, deletion/deletion (DD) and deletion/insertion (DI), of the CBS844ins68 polymorphism were found in two groups with no clear differences in two genotypes and allele frequency distribution (P>0.05). There were significant differences in the three genotype frequencies (χ2=6.658, χ2=4.410, P<0.05) for MTHFR C677T locus genotypes CC, CT and TT. The Hcy levels in genotypes DD and DI had no significant differences (P>0.05) and the CT and TT types were significantly higher compared to the CC genotype (P<0.05). The CC/DD combined genotype in the two groups was significantly different (P<0.05), and the odds ratio (OR), 0.569 showed that the CC/DD genotype may be a protective factor of hypertension. In the two groups, the Hcy levels for combined genotypes CC/DD, CT/DD, TT/DD and TT/DI were significantly different (P<0.05). The SHEsis software analysis linkage disequilibrium coefficient=0.216, indicates that there is probably a weak linkage for MTHFR C677T and CBS844ins68. Haplotype analysis suggested that the C-D haplotype was negatively correlated with EH (OR, 0.727) and that there was a positive correlation between T-D haplotype and EH (OR, 1.376). MTHFR C677T and CBS844ins68 polymorphisms were present in the populations studied and the CBS844ins68 homozygous mutation was not present. Therefore, there is a correlation between the polymorphisms of the MTHFR C677T gene and EH, and allele T may be one of the predisposing factors. MTHFR C677T and CBS844ins68 may exist with a certain linkage and the T-D haplotype may be a risk factor for EH. PMID:25279160

Bioconversion of giant reed (Arundo donax L.) hemicellulose hydrolysate to ethanol by Scheffersomyces stipitis CBS6054

Treesearch

Danilo Scordia; Salvatore L. Cosentino; Jae-Won Lee; Thomas W. Jeffries

2012-01-01

The objective of this study was to evaluate the production of ethanol by Scheffersomyces (Pichia) stipitis CBS6054, a native xylose fermenting yeast, from sugars contained in the giant reed (Arundo donax L.) hemicellulosic hydrolysate.

Dual Influence of Endocannabinoids on Long-Term Potentiation of Synaptic Transmission

PubMed Central

Silva-Cruz, Armando; Carlström, Mattias; Ribeiro, Joaquim A.; Sebastião, Ana M.

2017-01-01

Cannabinoid receptor 1 (CB1R) is widely distributed in the central nervous system, in excitatory and inhibitory neurons, and in astrocytes. CB1R agonists impair cognition and prevent long-term potentiation (LTP) of synaptic transmission, but the influence of endogenously formed cannabinoids (eCBs) on hippocampal LTP remains ambiguous. Based on the knowledge that eCBs are released upon high frequency neuronal firing, we hypothesized that the influence of eCBs upon LTP could change according to the paradigm of LTP induction. We thus tested the influence of eCBs on hippocampal LTP using two θ-burst protocols that induce either a weak or a strong LTP. LTP induced by a weak-θ-burst protocol is facilitated while preventing the endogenous activation of CB1Rs. In contrast, the same procedures lead to inhibition of LTP induced by the strong-θ-burst protocol, suggestive of a facilitatory action of eCBs upon strong LTP. Accordingly, an inhibitor of the metabolism of the predominant eCB in the hippocampus, 2-arachidonoyl-glycerol (2-AG), facilitates strong LTP. The facilitatory action of endogenous CB1R activation does not require the activity of inhibitory A1 adenosine receptors, is not affected by inhibition of astrocytic metabolism, but involves inhibitory GABAergic transmission. The continuous activation of CB1Rs via exogenous cannabinoids, or by drugs known to prevent metabolism of the non-prevalent hippocampal eCB, anandamide, inhibited LTP. We conclude that endogenous activation of CB1Rs by physiologically formed eCBs exerts a fine-tune homeostatic control of LTP in the hippocampus, acting as a high-pass filter, therefore likely reducing the signal-to-noise ratio of synaptic strengthening. PMID:29311928

Cdc42 is required in a genetically distinct subset of cardiac cells during Drosophila dorsal vessel closure

PubMed Central

Swope, David; Kramer, Joseph; King, Tiffany R.; Cheng, Yi-Shan; Kramer, Sunita G.

2017-01-01

The embryonic heart tube is formed by the migration and subsequent midline convergence of two bilateral heart fields. In Drosophila the heart fields are organized into two rows of cardioblasts (CBs). While morphogenesis of the dorsal ectoderm, which lies directly above the Drosophila dorsal vessel (DV), has been extensively characterized, the migration and concomitant fundamental factors facilitating DV formation remain poorly understood. Here we provide evidence that DV closure occurs at multiple independent points along the A-P axis of the embryo in a “buttoning” pattern, divergent from the zippering mechanism observed in the overlying epidermis during dorsal closure. Moreover, we demonstrate that a genetically distinct subset of CBs is programmed to make initial contact with the opposing row. To elucidate the cellular mechanisms underlying this process, we examined the role of Rho GTPases during cardiac migration using inhibitory and overexpression approaches. We found that Cdc42 shows striking cell-type specificity during DV formation. Disruption of Cdc42 function specifically prevents CBs that express the homeobox gene tinman from completing their dorsal migration, resulting in a failure to make connections with their partnering CBs. Conversely, neighboring CBs that express the orphan nuclear receptor, seven-up, are not sensitive to Cdc42 inhibition. Furthermore, this phenotype was specific to Cdc42 and was not observed upon perturbation of Rac or Rho function. Together with the observation that DV closure occurs through the initial contralateral pairing of tinman-expressing CBs, our studies suggest that the distinct buttoning mechanism we propose for DV closure is elaborated through signaling pathways regulating Cdc42 activity in this cell type. PMID:24949939

The Future of the Air National Guard

DTIC Science & Technology

2013-04-30

41 Keteyian, Armen , CBS Evening News, (August 2, 2012), accessed February 23, 2013, www.cbsnews.com/8301-18563_162-57485847/ex-official-chemical...Avgar. Crisis as an Opportunity. New York: University Press of America, Inc., 2011. Keteyian, Armen . "CBS Evening News." August 2, 2012

Clinical, cognitive and anatomical evolution from nonfluent progressive aphasia to corticobasal syndrome: a case report.

PubMed

Gorno-Tempini, Maria Luisa; Murray, Ryan C; Rankin, Katherine P; Weiner, Michael W; Miller, Bruce L

2004-12-01

Recent clinical and pathological studies have suggested that frontotemporal lobar degeneration (FTLD) and corticobasal syndrome (CBS) show clinical and pathological overlap. We present four years of longitudinal clinical, cognitive and anatomical data in the case of a 56-year-old woman, AS, whose clinical picture evolved from FTLD to CBS. For the first three years, AS showed a progressive speech and language disorder compatible with a diagnosis of the nonfluent aphasia variant of FTLD. At year four, 10 years after her first symptom, AS developed the classical clinical signs of CBS, including alien limb phenomenon and dystonia. Voxel-based morphometry (VBM) applied to AS's four annual scans showed progression of atrophy from the inferior posterior frontal gyrus, to the left insula and finally to the medial frontal lobe. This case demonstrates the clinical overlap between FTLD and CBS and shows that the two can appear in the same patient at different stages of the disease in relation to the progression of anatomical damage.

Comparative Proteome Analysis between High Lipid-Producing Strain Mucor circinelloides WJ11 and Low Lipid-Producing Strain CBS 277.49.

PubMed

Tang, Xin; Chen, Haiqin; Gu, Zhennan; Zhang, Hao; Chen, Yong Q; Song, Yuanda; Chen, Wei

2017-06-21

Mucor circinelloides is one of few oleaginous fungi that produces a useful oil rich in γ-linolenic acid, but it usually only produces <25% total lipid. Nevertheless, we isolated a new strain WJ11 that can produce up to 36% lipid of cell dry weight. In this study, we have systematically analyzed the global changes in protein levels between the high lipid-producing strain WJ11 and the low lipid-producing strain CBS 277.49 (15%, lipid/cell dry weight) at lipid accumulation phase through comparative proteome analysis. Proteome analysis demonstrated that the branched-chain amino acid and lysine metabolism, glycolytic pathway, and pentose phosphate pathway in WJ11 were up-regulated, while the activities of tricarboxylic acid cycle and branch point enzyme for synthesis of isoprenoids were retarded compared with CBS 277.49. The coordinated regulation at proteome level indicate that more acetyl-CoA and NADPH are provided for fatty acid biosynthesis in WJ11 compared with CBS 277.49.

Endurance tests with large-bore tapered-roller bearings to 2.2 million DN

NASA Technical Reports Server (NTRS)

Parker, R. J.; Signer, H. R.; Pinel, S. I.

1981-01-01

Endurance life tests were run with standard design and optimized high-speed design 120.65-mm-(4.750-in.-) bore tapered-roller bearings at shaft speeds of 12,500 and 18,500 rpm, respectively. Standard design bearings of vacuum melted AISI 4320 and CBS-1000M, and high-speed design bearings of CBS-1000M and through-hardened AISI M-50 were run under heavy combined radial and thrust load until fatigue failure or until a preset cutoff time of 1100 hours was reached. Standard design bearings made from CBS 1000M material ran to a 10 percent life approximately six times rated catalog life. Twelve identical bearings of AISI 4320 material ran to ten times rated catalog life without failure. Cracking and fracture of the cones of AISI M-50 high-speed design bearings occurred at 18,500 rpm due to high tensile hoop stresses. Four CBS 1000M high-speed design bearings ran to twenty-four times rated catalog life without any spalling, cracking or fracture failures.

[The Charles Bonnet syndrome: a case report and a brief review].

PubMed

Saiz Gonzáles, D; Diaz Marsá, M

2003-01-01

The Charles Bonnet syndrome (CBS) is a rare disease that also seems to be generally misdiagnosed. Initially described in the XVIII century by the philosopher with the same name, it consist in complex visual hallucinations in elderly people who suffer sensory deprivation with no other psychopathology. The hypothesis on the neurophysiology of hallucinations suggests, as in other diseases that present hallucinations, some implication of thalamus-cortex pathway release. Some authors have proposed CBS as an early marker of dementia and Parkinson's disease. Nevertheless, the results in functional neuroimaging are not conclusive. Regarding treatment, typical and atypical neuroleptics do not seem to be useful and recent studies suggest that the new anticonvulsants could be effcient. The patient should be informed about CBS as a . In the case reported, the patient presented complex hallucinations with normal SPECT and neuropsychological examinations. The patient did not respond to treatment with risperidone, presenting a favorable evolucion with valpromide. Although further research is needed, this case report supports the efficacy of valpromide in CBS.

Making Sense for Society

NASA Astrophysics Data System (ADS)

van der Heide, J. J.; Grus, M. M.; Nouwens, J. C. A. J.

2017-09-01

The Netherlands is a densely populated country. Cities in the metropolitan area (Randstad) will be growing at a fast pace in the coming decades1. Cities like Amsterdam and Rotterdam are being overrun by tourists. Climate change effects are noticed in cities (heavy rains for instance). Call for circular economy rises. Traffic increases. People are more self-reliant. Public space is shared by many functions. These challenges call for smart answers, more specific and directly than ever before. Sensor data is a cornerstone of these answers. In this paper we'll discuss the approaches of Dutch initiatives using sensor data as the new language to live a happy life in our cities. Those initiatives have been bundled in a knowledge platform called "Making sense for society" 1 https://www.cbs.nl/nl-nl/nieuws/2016/37/pbl-cbs-prognose-groei-steden-zet-door (in dutch)

User perceptions of and willingness to pay for household container-based sanitation services: experience from Cap Haitien, Haiti

PubMed Central

Russel, Kory; Tilmans, Sebastien; Kramer, Sasha; Sklar, Rachel; Tillias, Daniel; Davis, Jennifer

2015-01-01

Household-level container-based sanitation (CBS) services may help address the persistent challenge of providing effective, affordable sanitation services for which low-income urban households are willing to pay. Little is known, however, about user perceptions of and demand for household CBS services. This study presents the results of a pilot CBS service programme in Cap Haitien, Haiti. One hundred and eighteen households were randomly selected to receive toilets and a twice-weekly collection service. After three months, changes in these households’ satisfaction with their sanitation situation, along with feelings of pride, modernity and personal safety, were compared to 248 households in two comparison cohorts. Following the service pilot, 71 per cent of participating households opted to continue with the container-based sanitation service as paying subscribers. The results from this study suggest that, in the context of urban Haiti, household CBS systems have the potential to satisfy many residents’ desire for safe, convenient and modern sanitation services. PMID:26640322

``Phantom'' Modes in Ab Initio Tunneling Calculations: Implications for Theoretical Materials Optimization, Tunneling, and Transport

NASA Astrophysics Data System (ADS)

Barabash, Sergey V.; Pramanik, Dipankar

2015-03-01

Development of low-leakage dielectrics for semiconductor industry, together with many other areas of academic and industrial research, increasingly rely upon ab initio tunneling and transport calculations. Complex band structure (CBS) is a powerful formalism to establish the nature of tunneling modes, providing both a deeper understanding and a guided optimization of materials, with practical applications ranging from screening candidate dielectrics for lowest ``ultimate leakage'' to identifying charge-neutrality levels and Fermi level pinning. We demonstrate that CBS is prone to a particular type of spurious ``phantom'' solution, previously deemed true but irrelevant because of a very fast decay. We demonstrate that (i) in complex materials, phantom modes may exhibit very slow decay (appearing as leading tunneling terms implying qualitative and huge quantitative errors), (ii) the phantom modes are spurious, (iii) unlike the pseudopotential ``ghost'' states, phantoms are an apparently unavoidable artifact of large numerical basis sets, (iv) a presumed increase in computational accuracy increases the number of phantoms, effectively corrupting the CBS results despite the higher accuracy achieved in resolving the true CBS modes and the real band structure, and (v) the phantom modes cannot be easily separated from the true CBS modes. We discuss implications for direct transport calculations. The strategy for dealing with the phantom states is discussed in the context of optimizing high-quality high- κ dielectric materials for decreased tunneling leakage.

Effects of self-ligating brackets on oral hygiene and discomfort: a systematic review and meta-analysis of randomized controlled clinical trials.

PubMed

Yang, X; Su, N; Shi, Z; Xiang, Z; He, Y; Han, X; Bai, D

2017-02-01

Self-ligating brackets (SLBs) are widely adopted in clinic owing to their claimed superiorities. Here, we collected and analysed all randomized controlled clinical trials (RCTs) comparing SLBs with conventional brackets (CBs) and thereby investigated whether SLBs can relieve discomfort or promote oral hygiene. Electronic databases including MEDLINE, Cochrane Central Register of Controlled Trials, EMBASE, World Health Organization International Clinical Trials Registry Platform, Chinese BioMedical Literature Database and the China National Knowledge Infrastructure were searched to find out RCTs comparing active or passive SLBs with CBs. Two reviewers extracted the data and assessed risks of bias independently. Any disagreement between them was resolved through discussion with a third reviewer. Meta-analysis was conducted on Review Manager 5.3. A total of 12 RCTs with 575 participants were included, and eight of the trials were synthesized quantitatively. Two trials were assessed as low risk of bias, whereas others as unclear risk of bias. Passive SLBs and CBs are not significantly different in plaque control. SLBs and CBs are not significantly different in discomfort reduction at any of four time points (4 h, 24 h, 3 days and 7 days). Clinical evidences from existing RCTs suggest that SLBs do not outperform CBs in reliving discomfort or promoting oral health in clinic. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Intrahippocampal administration of anandamide increases REM sleep.

PubMed

Rueda-Orozco, Pavel Ernesto; Soria-Gómez, Edgar; Montes-Rodríguez, Corinne Jennifer; Pérez-Morales, Marcel; Prospéro-García, Oscar

2010-04-05

A nascent literature has postulated endocannabinoids (eCBs) as strong sleep-inducing lipids, particularly rapid-eye-movement sleep (REMs), nevertheless the exact mechanisms behind this effect remain to be determined. Anandamide and 2-arachidonyl glycerol, two of the most important eCBS, are synthesized in the hippocampus. This structure also expresses a high concentration of cannabinoid receptor 1 (CB1). Recent extensive literature supports eCBs as important regulators of hippocampal activity. It has also been shown that these molecules vary their expression on the hippocampus depending on the light-dark cycle. In this context we decided to analyze the effect of intrahippocampal administration of the eCB anandamide (ANA) on the sleep-waking cycle at two points of the light-dark cycle. Our data indicate that the administration of ANA directly into the hippocampus increases REMs in a dose dependent manner during the dark but not during the light phase of the cycle. The increase of REMs was blocked by the CB1 antagonist AM251. This effect was specific for the hippocampus since ANA administrations in the surrounding cortex did not elicit any change in REMs. These results support the idea of a direct relationship between hippocampal activity and sleep mechanisms by means of eCBs. The data presented here show, for the first time that eCBs administered into the hippocampus trigger REMs and support previous studies where chemical stimulation of limbic areas triggered sleep.

Investigation on the preparation and chromatographic behavior of a new para-tert-butylcalix[4]arene-1,2-crown-4 stationary phase for high performance liquid chromatography.

PubMed

Hu, Kai; Zhao, Wenjie; Wen, Fuyong; Liu, Junwei; Zhao, Xiaolan; Xu, Zhanhui; Niu, Bailin; Ye, Baoxian; Wu, Yangjie; Zhang, Shusheng

2011-07-15

In the present work, a new para-tert-butylcalix[4]arene-1,2-crown-4 bonded silica stationary phase (CBS4-4) was synthesized, structurally characterized, and employed to separate polycyclic aromatic hydrocarbons (PAHs), phenols, aromatic amines, benzoic acid and its derivatives. The chromatographic behaviors of the prepared stationary phase were investigated and compared with ODS. The effects of methanol concentrations on the retention index show that CBS4-4 exhibits high selectivity for the above analytes. The separation mechanisms based on the different interactions between calixarene and the analytes were discussed. With the assistance of quantum chemistry calculation, the interaction Gibbs free energy change ΔG(solv) (in the mobile phase) of p, m and o-phenylenediamine positional isomers and para-tert-butylcalix[4]arene-1,2-crown-4 were obtained. The ΔG(solv) values were consistent with the retention behavior of p, m and o-phenylenediamine on the CBS4-4. According to the chromatographic data, it can be concluded that the selectivity of CBS4-4 for analytes is mainly ascribed to hydrophobic interaction, accompanied by other effects such as hydrogen bonding interaction, π-π and inclusion interaction. The CBS4-4 column has been successfully employed for the analysis of benzoic acid in Sprite drink. Copyright © 2011 Elsevier B.V. All rights reserved.

Surface fatigue life and failure characteristics of EX-53, CBS 1000M, and AISI 9310 gear materials

NASA Technical Reports Server (NTRS)

Townsend, D. P.

1985-01-01

Spur gear endurance tests and rolling-element surface fatigue tests are conducted to investigate EX-53 and CBS 1000M steels for use as advanced application gear materials, to determine their endurance characteristics, and to compare the results with the standard AISI 9310 gear material. The gear pitch diameter is 8.89 cm (3.50 in). Gear test conditions are an oil inlet temperature of 320 K (116 F), an oil outlet temperature of 350 K (170 F), a maximum Hertz stress of 1.71 GPa (248 ksi), and a speed of 10,000 rpm. Bench-type rolling-element fatigue tests are conducted at ambient temperature with a bar specimen speed of 12,500 rpm and a maximum Hertz stress of 4.83 GPa (700 ksi). The EX-53 test gears have a surface fatigue life of twice that of the AISI 9310 spur gears. The CBS 1000M test gears have a surface fatigue life of more than twice that of the AISI 9310 spur gears. However, the CBS 1000M gears experience a 30-percent tooth fracture failure which limits its use as a gear material. The rolling-contact fatigue lines of RC bar specimens of EX-53 and ASISI 9310 are approximately equal. However, the CBS 1000M RC specimens have a surface fatigue life of about 50 percent that of the AISI 9310.

CBS mutations and MTFHR SNPs causative of hyperhomocysteinemia in Pakistani children.

PubMed

Ibrahim, Shahnaz; Maqbool, Saadia; Azam, Maleeha; Iqbal, Mohammad Perwaiz; Qamar, Raheel

2018-03-29

Three index patients with hyperhomocysteinemia and ocular anomalies were screened for cystathionine beta synthase (CBS) and methylenetetrahydrofolate reductase (MTHFR) polymorphisms. Genotyping of hyperhomocysteinemia associated MTHFR polymorphisms C677T (rs1801133) and A1298C (rs1801131) was done by PCR-restriction fragment length polymorphism. Sanger sequencing was performed for CBS exonic sequences along with consensus splice sites. In the case of MTHFR polymorphisms, all the patients were heterozygous CT for the single nucleotide polymorphism (SNP) C677T and were therefore carriers of the risk allele (T), while the patients were homozygous CC for the risk genotype of the SNP A1298C. CBS sequencing resulted in the identification of two novel mutations, a missense change (c.467T>C; p.Leu156Pro) in exon 7 and an in-frame deletion (c.808_810del; p.Glu270del) in exon 10. In addition, a recurrent missense mutation (c.770C>T; p.Thr257Met) in exon 10 of the gene was also identified. The mutations were present homozygously in the patients and were inherited from the carrier parents. This is the first report from Pakistan where novel as well as recurrent CBS mutations causing hyperhomocysteinemia and lens dislocation in three patients from different families are being reported with the predicted effect of the risk allele of the MTHFR SNP in causing hyperhomocysteinemia.

Transversal changes, space closure, and efficiency of conventional and self-ligating appliances : A quantitative systematic review.

PubMed

Yang, Xianrui; Xue, Chaoran; He, Yiruo; Zhao, Mengyuan; Luo, Mengqi; Wang, Peiqi; Bai, Ding

2018-01-01

Self-ligating brackets (SLBs) were compared to conventional brackets (CBs) regarding their effectiveness on transversal changes and space closure, as well as the efficiency of alignment and treatment time. All previously published randomized controlled clinical trials (RCTs) dealing with SLBs and CBs were searched via electronic databases, e.g., MEDLINE, Cochrane Central Register of Controlled Trials, EMBASE, World Health Organization International Clinical Trials Registry Platform, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure. In addition, relevant journals were searched manually. Data extraction was performed independently by two reviewers and assessment of the risk of bias was executed using Cochrane Collaboration's tool. Discrepancies were resolved by discussion with a third reviewer. Meta-analyses were conducted using Review Manager (version 5.3). A total of 976 patients in 17 RCTs were included in the study, of which 11 could be produced quantitatively and 2 showed a low risk of bias. Meta-analyses were found to favor CB for mandibular intercanine width expansion, while passive SLBs were more effective in posterior expansion. Moreover, CBs had an apparent advantage during short treatment periods. However, SLBs and CBs did not differ in closing spaces. Based on current clinical evidence obtained from RCTs, SLBs do not show clinical superiority compared to CBs in expanding transversal dimensions, space closure, or orthodontic efficiency. Further high-level studies involving randomized, controlled, clinical trials are warranted to confirm these results.

FUS and TDP43 genetic variability in FTD and CBS

PubMed Central

Huey, Edward D.; Ferrari, Raffaele; Moreno, Jorge H.; Jensen, Christopher; Morris, Christopher M.; Potocnik, Felix; Kalaria, Rajesh N.; Tierney, Michael; Wassermann, Eric M.; Hardy, John; Grafman, Jordan; Momeni, Parastoo

2015-01-01

This study aimed to evaluate genetic variability in the FUS and TDP-43 genes, known to be mainly associated with amyotrophic lateral sclerosis (ALS), in patients with the diagnoses of frontotemporal lobar degeneration (FTLD) and corticobasal syndrome (CBS). We screened the DNA of 228 patients for all the exons and flanking introns of FUS and TDP-43 genes. We identified 2 novel heterozygous missense mutations in FUS: P106L (g.22508384>T) in a patient with behavioral variant frontotemporal dementia (bvFTD) and Q179H in several members of a family with behavioral variant FTD. We also identified the N267S mutation in TDP-43 in a CBS patient, previously only reported in 1 ALS family and 1 FTD patient. Additionally, we identified 2 previously reported heterozygous insertion and deletion mutations in Exon 5 of FUS; Gly174-Gly175 del GG (g. 4180–4185 delGAGGTG) in an FTD patient and Gly175-Gly176 ins GG (g. 4185–4186 insGAGGTG) in a patient with diagnosis of CBS. Not least, we have found a series of variants in FUS also in neurologically normal controls. In summary, we report that genetic variability in FUS and TDP-43 encompasses a wide range of phenotypes (including ALS, FTD, and CBS) and that there is substantial genetic variability in FUS gene in neurologically normal controls. PMID:21943958

The SMN Protein is a Key Regulator of Nuclear Architecture in Differentiating Neuroblastoma Cells

PubMed Central

Clelland, Allyson K; Kinnear, Nicholas P; Oram, Lisa; Burza, Julie; Sleeman, Judith E

2009-01-01

The cell nucleus contains two closely related structures, Cajal bodies (CBs) and gems. CBs are the first site of accumulation of newly assembled splicing snRNPs (small nuclear ribonucleoproteins) following their import into the nucleus, before they form their steady-state localization in nuclear splicing speckles. Gems are the nuclear site of accumulation of survival motor neurons (SMNs), an insufficiency of which leads to the inherited neurodegenerative condition, spinal muscular atrophy (SMA). SMN is required in the cytoplasm for the addition of core, Sm, proteins to new snRNPs and is believed to accompany snRNPs to the CB. In most cell lines, gems are indistinguishable from CBs, although the structures are often separate in vivo. The relationship between CBs and gems is not fully understood, but there is evidence that symmetrical dimethylation of arginine residues in the CB protein coilin brings them together in HeLa cells. During neuronal differentiation of the human neuroblastoma cell line SH-SY5Y, CBs and gems increase their colocalization, mimicking changes seen during foetal development. This does not result from alterations in the methylation of coilin, but from increased levels of SMN. Expression of exogenous SMN results in an increased efficiency of snRNP transport to nuclear speckles. This suggests different mechanisms are present in different cell types and in vivo that may be significant for the tissue-specific pathology of SMA. PMID:19735367

Oculomotor Function in Frontotemporal Lobar Degeneration, Related Disorders and Alzheimer's Disease

ERIC Educational Resources Information Center

Garbutt, Siobhan; Matlin, Alisa; Hellmuth, Joanna; Schenk, Ana K.; Johnson, Julene K.; Rosen, Howard; Dean, David; Kramer, Joel; Neuhaus, John; Miller, Bruce L.; Lisberger, Stephen G.; Boxer, Adam L.

2008-01-01

Frontotemporal lobar degeneration (FTLD) often overlaps clinically with corticobasal syndrome (CBS) and progressive supranuclear palsy (PSP), both of which have prominent eye movement abnormalities. To investigate the ability of oculomotor performance to differentiate between FTLD, Alzheimer's disease, CBS and PSP, saccades and smooth pursuit were…

Anxiety and Charles Bonnet Syndrome

ERIC Educational Resources Information Center

Geueke, Anna; Morley, Michael G.; Morley, Katharine; Lorch, Alice; Jackson, MaryLou; Lambrou, Angeliki; Wenberg, June; Oteng-Amoako, Afua

2012-01-01

Introduction: Some persons with Charles Bonnet syndrome (CBS) suffer significant anxiety because of their visual hallucinations, while others do not. The aim of the study presented here was to compare levels of anxiety in persons with low vision with and without CBS. Methods: This retrospective study compared the level of anxiety in 31 persons…

Rhodotorula rosulata sp. nov., Rhodotorula silvestris sp. nov. and Rhodotorula straminea sp. nov., novel myo-inositol-assimilating yeast species in the Microbotryomycetes.

PubMed

Golubev, Wladyslav I; Scorzetti, Gloria

2010-10-01

Three novel species are described as Rhodotorula rosulata sp. nov. (type strain VKM Y-2962(T) =CBS 10977(T)), Rhodotorula silvestris sp. nov. (type strain VKM Y-2971(T) =CBS 11420(T)) and Rhodotorula straminea sp. nov. (type strain VKM Y-2964(T) =CBS 10976(T)) based on the study of eight isolates from needle litter. The new species, phylogenetically located within the Microbotryomycetes, are related to glucuronate-assimilating species of the genus Rhodotorula. Sequencing of the D1/D2 domains of the LSU rDNA gene and the internal transcribed spacer (ITS) region, as well as physiological characterization, revealed their distinct taxonomic positions.

A convenient enantioselective CBS-reduction of arylketones in flow-microreactor systems.

PubMed

De Angelis, Sonia; De Renzo, Maddalena; Carlucci, Claudia; Degennaro, Leonardo; Luisi, Renzo

2016-05-04

A convenient, versatile, and green CBS-asymmetric reduction of aryl and heteroaryl ketones has been developed by using the microreactor technology. The study demonstrates that it is possible to handle borane solution safely within microreactors and that the reaction performs well using 2-MeTHF as a greener solvent.

School Engagement and Parental Involvement: The Case of Cross-Border Students in Singapore

ERIC Educational Resources Information Center

Yuen, Celeste Y. M.; Cheung, Alan C. K.

2014-01-01

The primary purpose of this paper is to examine the mutual relationship between school engagement of cross-border students (CBS) from Malaysia in Singapore and parental involvement in education. Focus-group interviews were conducted with school personnel, CBS and their non-local counterparts to provide a comprehensive understanding of the…

Long-term performance of thermoplastic composite material with cotton burr and stem (CBS) as a partial filler

USDA-ARS?s Scientific Manuscript database

Rationale: Cotton burr and stem (CBS) fraction of cotton gin byproducts has shown promise as a fiber filler in thermoplastic composites, with physical and mechanical properties comparable to that made with wood fiber fillers. However, the long-term performance of this composite material is not known...

New anamorphic yeast species: Candida infanticola sp. nov., Candida polysorbophila sp. nov., Candida transvaalensis sp. nov. and Trigonopsis californica sp. nov.

PubMed

Kurtzman, Cletus P

2007-08-01

Three new species of Candida and a new species of Trigonopsis are described based on their recognition from phylogenetic analysis of gene sequences from large subunit ribosomal RNA, ITS1/ITS2 rRNA, mitochondrial small subunit rRNA and cytochrome oxidase II. Candida infanticola sp. nov. (type strain NRRL Y-17858, CBS 7922) was isolated from the ear of an infant in Germany and is closely related to Candida sorbophila. Candida polysorbophila sp. nov. (type strain NRRL Y-27161, CBS 7317) is a member of the Zygoascus clade and was isolated in South Africa as a contaminant from an emulsion of white oil and polysorbate. Candida transvaalensis sp. nov. (type strain NRRL Y-27140, CBS 6663) was obtained from forest litter, the Transvaal, South Africa, and forms an isolated clade with Candida santjacobensis. Trigonopsis californica sp. nov. (type strain NRRL Y-27307, CBS 10351) represents a contaminant from wine in California, and forms a well-supported clade with Trigonopsis cantarellii, Trigonopsis variabilis and Trigonopsis vinaria.

Charles Bonnet syndrome in hemianopia, following antero-mesial temporal lobectomy for drug-resistant epilepsy.

PubMed

Contardi, Sara; Rubboli, Guido; Giulioni, Marco; Michelucci, Roberto; Pizza, Fabio; Gardella, Elena; Pinardi, Federica; Bartolomei, Ilaria; Tassinari, Carlo Alberto

2007-09-01

Charles Bonnet syndrome (CBS) is a disorder characterized by the occurrence of complex visual hallucinations in patients with acquired impairment of vision and without psychiatric disorders. In spite of the high incidence of visual field defects following antero-mesial temporal lobectomy for refractory temporal lobe epilepsy, reports of CBS in patients who underwent this surgical procedure are surprisingly rare. We describe a patient operated on for drug-resistant epilepsy. As a result of left antero-mesial temporal resection, she presented right homonymous hemianopia. A few days after surgery, she started complaining of visual hallucinations, such as static or moving "Lilliputian" human figures, or countryside scenes, restricted to the hemianopic field. The patient was fully aware of their fictitious nature. These disturbances disappeared progressively over a few weeks. The incidence of CBS associated with visual field defects following epilepsy surgery might be underestimated. Patients with post-surgical CBS should be reassured that it is not an epileptic phenomenon, and that it has a benign, self-limiting, course which does not usually require treatment.

Prosopo-affective agnosia associated with chronic organic brain syndrome.

PubMed

Kurucz, J; Feldmar, G; Werner, W

1979-02-01

Impairment of the ability to recognize facially expressed emotions was studied in 14 chronically disoriented patients with chronic organic brain syndrome (CBS). This impairment was named prosopo-affective agnosia (PAA). A diagnostic requirement was relatively intact neurologic functioning in underlying perceptual-verbal-motor processing. A test was designed for facial-affect recognition in the accurate differentiation of normal persons from chronically disoriented CBS patients. No normal subject made any errors in this test. Despite decades of illness and hospital living, patients with a history of schizophrenia or major affective disorders scored almost at a normal level (95 vs. 100 percent) in this test, and significantly higher (95 vs. 66 percent) than did the disoriented CBS patients. The social and therapeutic implications of the findings are stressed. CBS patients may be impaired with respect to receiving and appreciating elementary aspects of social communications such as recognizing a smile, anger, sadness or disapproval on the faces of people who surround them. This disability requires understanding and a special attitude on the part of the therapeutic team toward such patients.

In vitro hypoglycemic and cholesterol lowering effects of dietary fiber prepared from cocoa (Theobroma cacao L.) shells.

PubMed

Nsor-Atindana, John; Zhong, Fang; Mothibe, Kebitsamang Joseph

2012-10-01

Three dietary fiber (DF) powders; soluble dietary fiber (SDF), insoluble dietary fiber (IDF) and total dietary fiber (TDF) were prepared from cocoa bean shells (CBS) by enzymatic treatment. These DFs were evaluated for their effects on glucose adsorption, glucose diffusion, starch hydrolysis, cholesterol binding, sodium cholate binding and oil binding capacities using in vitro model systems by simulating gastric intestinal conditions. The results showed that SDF generally exhibited significantly (p < 0.05) higher glucose adsorption capacity (GAC), α-amylase inhibition activity, cholesterol and sodium cholate binding capacity, but less significant (>0.05) glucose dialysis retardation index (GDRI) and oil binding capacity, when compared with IDF and TDF which both showed similar effects. Moreover, it was discovered that the three CBS dietary fiber powders contained intrinsic antioxidants (phenolic compounds). The study suggested that CBS could be an alternative cheap source of DF with additional benefits. Thus, CBS fibers could be incorporated as low calorie bulk ingredients in high-fiber diet to reduce calorie and cholesterol levels and control blood glucose level.

Treatments for the challenging behaviours of adults with intellectual disabilities.

PubMed

Matson, Johnny L; Neal, Daniene; Kozlowski, Alison M

2012-10-01

To provide an overview and critical assessment of common problems and best evidence practice in treatments for the challenging behaviours (CBs) of adults with intellectual disabilities (IDs). Commonly observed problems that present obstacles to successful treatment plans are discussed, followed by an analysis of available research on the efficacy of behavioural and pharmacological therapies. Behavioural and pharmacological interventions are most commonly used when addressing CBs in people with IDs. However, within each of these techniques, there are methods that have support in the literature for efficacy and those that do not. As clinicians, it is important to follow research so that we are engaging in best practices when developing treatment plans for CBs. One of the most consuming issues for psychiatrists and other mental health professionals who work with people who evince developmental disabilities, such as IDs, are CBs. These problems are very dangerous and are a major impediment to independent, less restrictive living. However, there is a major gap between what researchers show is effective and much of what occurs in real-world settings.

Comparison of Biochemical Activities between High and Low Lipid-Producing Strains of Mucor circinelloides: An Explanation for the High Oleaginicity of Strain WJ11.

PubMed

Tang, Xin; Chen, Haiqin; Chen, Yong Q; Chen, Wei; Garre, Victoriano; Song, Yuanda; Ratledge, Colin

2015-01-01

The oleaginous fungus, Mucor circinelloides, is one of few fungi that produce high amounts of γ-linolenic acid (GLA); however, it usually only produces <25% lipid. Nevertheless, a new strain (WJ11) isolated in this laboratory can produce lipid up to 36% (w/w) cell dry weight (CDW). We have investigated the potential mechanism of high lipid accumulation in M. circinelloides WJ11 by comparative biochemical analysis with a low lipid-producing strain, M. circinelloides CBS 277.49, which accumulates less than 15% (w/w) lipid. M. circinelloides WJ11 produced more cell mass than that of strain CBS 277.49, although with slower glucose consumption. In the lipid accumulation phase, activities of glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase in strain WJ11 were greater than in CBS 277.49 by 46% and 17%, respectively, and therefore may provide more NADPH for fatty acid biosynthesis. The activities of NAD+:isocitrate dehydrogenase and NADP+:isocitrate dehydrogenase, however, were 43% and 54%, respectively, lower in WJ11 than in CBS 277.49 and may retard the tricarboxylic acid cycle and thereby provide more substrate for ATP:citrate lyase (ACL) to produce acetyl-CoA. Also, the activities of ACL and fatty acid synthase in the high lipid-producing strain, WJ11, were 25% and 56%, respectively, greater than in strain CBS 277.49. These enzymes may therefore cooperatively regulate the fatty acid biosynthesis in these two strains.

Primary hepatocytes from mice lacking cysteine dioxygenase show increased cysteine concentrations and higher rates of metabolism of cysteine to hydrogen sulfide and thiosulfate

PubMed Central

Jurkowska, Halina; Roman, Heather B.; Hirschberger, Lawrence L.; Sasakura, Kiyoshi; Nagano, Tetsuo; Hanaoka, Kenjiro; Krijt, Jakub

2016-01-01

The oxidation of cysteine in mammalian cells occurs by two routes: a highly regulated direct oxidation pathway in which the first step is catalyzed by cysteine dioxygenase (CDO) and by desulfhydration-oxidation pathways in which the sulfur is released in a reduced oxidation state. To assess the effect of a lack of CDO on production of hydrogen sulfide (H2S) and thiosulfate (an intermediate in the oxidation of H2S to sulfate) and to explore the roles of both cystathionine γ-lyase (CTH) and cystathionine β-synthase (CBS) in cysteine desulfhydration by liver, we investigated the metabolism of cysteine in hepatocytes isolated from Cdo1-null and wild-type mice. Hepatocytes from Cdo1-null mice produced more H2S and thiosulfate than did hepatocytes from wild-type mice. The greater flux of cysteine through the cysteine desulfhydration reactions catalyzed by CTH and CBS in hepatocytes from Cdo1-null mice appeared to be the consequence of their higher cysteine levels, which were due to the lack of CDO and hence lack of catabolism of cysteine by the cysteinesulfinate-dependent pathways. Both CBS and CTH appeared to contribute substantially to cysteine desulfhydration, with estimates of 56 % by CBS and 44 % by CTH in hepatocytes from wild-type mice, and 63 % by CBS and 37 % by CTH in hepatocytes from Cdo1-null mice. PMID:24609271

Starmerella reginensis f.a., sp. nov. and Starmerella kourouensis f.a., sp. nov., isolated from flowers in French Guiana.

PubMed

Amoikon, Tiemele Laurent Simon; Grondin, Cécile; Djéni, Théodore N'Dédé; Jacques, Noémie; Casaregola, Serge

2018-05-21

Analysis of yeasts isolated from various biotopes in French Guiana led to the identification of two strains isolated from flowers and designated CLIB 1634 T and CLIB 1707 T . Comparison of the D1/D2 domain of the large subunit (LSU D1/D2) rRNA gene sequences of CLIB 1634 T and CLIB 1707 T to those in the GenBank database revealed that these strains belong to the Starmerella clade. Strain CLIB 1634 T was shown to diverge from the closely related Starmerella apicola type strain CBS 2868 T with a sequence divergence of 1.34 and 1.30 %, in the LSU D1/D2 rRNA gene and internal transcribed spacer (ITS) sequences respectively. Strain CLIB 1634 T and Candida apicola CBS 2868 T diverged by 3.81 and 14.96 % at the level of the protein-coding gene partial sequences EF-1α and RPB2, respectively. CLIB 1707 T was found to have sequence divergence of 3.88 and 9.16 % in the LSU D1/D2 rRNA gene and ITS, respectively, from that of the most closely related species Starmerella ratchasimensis type strain CBS 10611 T . The species Starmerella reginensis f.a., sp. nov. and Starmerella kourouensis f.a., sp. nov. are proposed to accommodate strains CLIB 1634 T (=CBS 15247 T ) and CLIB 1707 T (=CBS 15257 T ), respectively.

Penicillium araracuarense sp. nov., Penicillium elleniae sp. nov., Penicillium penarojense sp. nov., Penicillium vanderhammenii sp. nov. and Penicillium wotroi sp. nov., isolated from leaf litter.

PubMed

Houbraken, Jos; López-Quintero, Carlos A; Frisvad, Jens C; Boekhout, Teun; Theelen, Bart; Franco-Molano, Ana Esperanza; Samson, Robert A

2011-06-01

Several species of the genus Penicillium were isolated during a survey of the mycobiota of leaf litter and soil in Colombian Amazon forest. Five species, Penicillium penarojense sp. nov. (type strain CBS 113178(T) = IBT 23262(T)), Penicillium wotroi sp. nov. (type strain CBS 118171(T) = IBT 23253(T)), Penicillium araracuarense sp. nov. (type strain CBS 113149(T) = IBT 23247(T)), Penicillium elleniae sp. nov. (type strain CBS 118135(T) = IBT 23229(T)) and Penicillium vanderhammenii sp. nov. (type strain CBS 126216(T) = IBT 23203(T)) are described here as novel species. Their taxonomic novelty was determined using a polyphasic approach, combining phenotypic, molecular (ITS and partial β-tubulin sequences) and extrolite data. Phylogenetic analyses showed that each novel species formed a unique clade for both loci analysed and that they were most closely related to Penicillium simplicissimum, Penicillium janthinellum, Penicillium daleae and Penicillium brasilianum. An overview of the phylogeny of this taxonomically difficult group is presented, and 33 species are accepted. Each of the five novel species had a unique extrolite profile of known and uncharacterized metabolites and various compounds, such as penicillic acid, andrastin A, pulvilloric acid, paxillin, paspaline and janthitrem, were commonly produced by these phylogenetically related species. The novel species had a high growth rate on agar media, but could be distinguished from each other by several macro- and microscopical characteristics.

Effects of 4-week self cross body stretching with scapular stabilization on shoulder motions and horizontal adductor strength in subjects with limited shoulder horizontal adduction.

PubMed

Joung, Ha-Na; Yi, Chung-Hwi; Jeon, Hye-Seon; Hwang, Ui-Jae; Kwon, Oh-Yun

2018-05-29

Posterior shoulder tightness (PST) is related to shoulder conditions such as shoulder impingement and limited shoulder horizontal adduction (SHA). The purpose of this study was to compare the effects of self cross body stretching (CBS) with and without scapular stabilization (SS) on SHA and shoulder internal rotation (SIR) range of motion (ROM) and shoulder horizontal adductor strength (SHAS) in subjects with limited SHA. Twenty-six subjects (14 males, 12 females) with limited SHA was participated in this study. The SS group and without stabilization (WS) group were assigned randomly. The SS group performed self CBS with SS by applying belt just under the subject's axilla. The subjects were asked to perform self CBS in 4 times a week for 4 weeks. SHA and SIR RM were measured by Clinometer smartphone application, and SHAS by hand-held dynamometer (HHD) before and after 4-week self CBS. 2 × 2 mixed analysis of variance (ANOVA) was used to identify the significance. If there was an interaction effect, t-test was used to confirm the simple effect. There was a significant interaction in SHA ROM and SHAS. The post-test value of SHA ROM was significantly greater in SS group than WS group (p < 0.0125). In SHAS, there was no significant difference between groups (p > 0.0125). SS during self CBS could enhance to improve SHA, SIR ROM, and SHAS in individuals with limited SHA.

A Clinically Relevant Variant of the Human Hydrogen Sulfide-Synthesizing Enzyme Cystathionine β-Synthase: Increased CO Reactivity as a Novel Molecular Mechanism of Pathogenicity?

PubMed Central

Malagrinò, Francesca; Santo, Paulo E.; Gutierres, André; Bandeiras, Tiago M.; Leandro, Paula

2017-01-01

The human disease classical homocystinuria results from mutations in the gene encoding the pyridoxal 5′-phosphate- (PLP-) dependent cystathionine β-synthase (CBS), a key enzyme in the transsulfuration pathway that controls homocysteine levels, and is a major source of the signaling molecule hydrogen sulfide (H2S). CBS activity, contributing to cellular redox homeostasis, is positively regulated by S-adenosyl-L-methionine (AdoMet) but fully inhibited upon CO or NO• binding to a noncatalytic heme moiety. Despite extensive studies, the molecular basis of several pathogenic CBS mutations is not yet fully understood. Here we found that the ferrous heme of the reportedly mild p.P49L CBS variant has altered spectral properties and markedly increased affinity for CO, making the protein much more prone than wild type (WT) CBS to inactivation at physiological CO levels. The higher CO affinity could result from the slightly higher flexibility in the heme surroundings revealed by solving at 2.80-Å resolution the crystallographic structure of a truncated p.P49L. Additionally, we report that p.P49L displays impaired H2S-generating activity, fully rescued by PLP supplementation along the purification, despite a minor responsiveness to AdoMet. Altogether, the results highlight how increased propensity to CO inactivation of an otherwise WT-like variant may represent a novel pathogenic mechanism in classical homocystinuria. PMID:28421128

Consequences of the trans-Atlantic slave trade on medicinal plant selection: plant use for cultural bound syndromes affecting children in Suriname and Western Africa.

PubMed

Vossen, Tessa; Towns, Alexandra; Ruysschaert, Sofie; Quiroz, Diana; van Andel, Tinde

2014-01-01

Folk perceptions of health and illness include cultural bound syndromes (CBS), ailments generally confined to certain cultural groups or geographic regions and often treated with medicinal plants. Our aim was to compare definitions and plant use for CBS regarding child health in the context of the largest migration in recent human history: the trans-Atlantic slave trade. We compared definitions of four CBS (walk early, evil eye, atita and fontanels) and associated plant use among three Afro-Surinamese populations and their African ancestor groups in Ghana, Bénin and Gabon. We expected plant use to be similar on species level, and assumed the majority to be weedy or domesticated species, as these occur on both continents and were probably recognized by enslaved Africans. Data were obtained by identifying plants mentioned during interviews with local women from the six different populations. To analyse differences and similarities in plant use we used Detrended Component Analysis (DCA) and a Wald Chi-square test. Definitions of the four cultural bound syndromes were roughly the same on both continents. In total, 324 plant species were used. There was little overlap between Suriname and Africa: 15 species were used on two continents, of which seven species were used for the same CBS. Correspondence on family level was much higher. Surinamese populations used significantly more weedy species than Africans, but equal percentages of domesticated plants. Our data indicate that Afro-Surinamers have searched for similar plants to treat their CBS as they remembered from Africa. In some cases, they have found the same species, but they had to reinvent the largest part of their herbal pharmacopeia to treat their CBS using known plant families or trying out new species. Ideas on health and illness appear to be more resilient than the use of plants to treat them.

Efficacy of ultraviolet light exposure against survival of Listeria monocytogenes on conveyor belts.

PubMed

Morey, Amit; McKee, Shelly R; Dickson, James S; Singh, Manpreet

2010-06-01

Listeria monocytogenes has been repeatedly isolated from foods and food-processing facilities including food contact surfaces such as conveyor belts (CB). CBs are often difficult to clean and require rigorous sanitation programs for decontamination. Ultraviolet (UV) light has exhibited microbicidal properties on food contact surfaces and this study was conducted to determine the efficacy of UV against L. monocytogenes on CB made of different materials. A four-strain cocktail of L. monocytogenes (serotypes 3A, 4A, 4B, and 4C) was made to give a suspension of approximately 10(7) CFU/mL. CBs made from four different types of materials, (1) Ropanyl DM 8/2 A2 + 04 (belt 1), (2) Volta FRMW-3.0 (belt 2), (3) Volta FRMB-3.0 (belt 3), and (4) Ropanyl DM (belt 4), were inoculated with 1 mL of the four-strain cocktail (approximately 10(7) CFU/mL) of the bacterial suspension. CBs were treated with UV light (254 nm) for 1 and 3 sec at 5.53 and 5.95 mW/cm(2). Three replications of the experiments were conducted. Two-way analysis of variance of survival populations of L. monocytogenes showed that bacterial counts were significantly reduced (p < 0.05) on all belt types irrespective of UV light intensities and times of exposure. L. monocytogenes populations were reduced (p < 0.05) to below detection limits on belts 1, 2, and 3 after exposure to 5.95 mW/cm(2) UV light intensity for 3 sec. L. monocytogenes-inoculated CBs that were exposed to 5.53 mW/cm(2) showed higher (p < 0.05) survival populations of L. monocytogenes compared with 5.95 mW/cm(2) on all the four CBs. Belt 4 showed survival populations of L. monocytogenes ranging from 1.42 to 1.73 log(10) CFU/cm(2) after UV light treatment for 1 and 3 sec. UV light can be effectively used to reduce L. monocytogenes contamination on CBs.

Thermochemistry of C7H16 to C10H22 alkane isomers: primary, secondary, and tertiary C-H bond dissociation energies and effects of branching.

PubMed

Hudzik, Jason M; Bozzelli, Joseph W; Simmie, John M

2014-10-09

Standard enthalpies of formation (ΔH°f 298) of methyl, ethyl, primary and secondary propyl, and n-butyl radicals are evaluated and used in work reactions to determine internal consistency. They are then used to calculate the enthalpy of formation for the tert-butyl radical. Other thermochemical properties including standard entropies (S°(T)), heat capacities (Cp(T)), and carbon-hydrogen bond dissociation energies (C-H BDEs) are reported for n-pentane, n-heptane, 2-methylhexane, 2,3-dimethylpentane, and several branched higher carbon number alkanes and their radicals. ΔH°f 298 and C-H BDEs are calculated using isodesmic work reactions at the B3LYP (6-31G(d,p) and 6-311G(2d,2p) basis sets), CBS-QB3, CBS-APNO, and G3MP2B3 levels of theory. Structures, moments of inertia, vibrational frequencies, and internal rotor potentials are calculated at the B3LYP/6-31G(d,p) level for contributions to entropy and heat capacities. Enthalpy calculations for these hydrocarbon radical species are shown to have consistency with the CBS-QB3 and CBS-APNO methods using all work reactions. Our recommended ideal gas phase ΔH°f 298 values are from the average of all CBS-QB3, CBS-APNO, and for G3MP2B3, only where the reference and target radical are identical types, and are compared with literature values. Calculated values show agreement between the composite calculation methods and the different work reactions. Secondary and tertiary C-H bonds in the more highly branched alkanes are shown to have bond energies that are several kcal mol(-1) lower than the BDEs in corresponding smaller molecules often used as reference species. Entropies and heat capacities are calculated and compared to literature values (when available) when all internal rotors are considered.

Comparative Effects of Parathion and Chlorpyrifos on Endocannabinoid and Endocannabinoid-Like Lipid Metabolites in Rat Striatum

PubMed Central

Liu, Jing; Parsons, Loren; Pope, Carey

2015-01-01

Parathion and chlorpyrifos are organophosphorus insecticides (OPs) that elicit acute toxicity by inhibiting acetylcholinesterase (AChE). The endocannabinoids (eCBs, N-arachidonoylethanolamine, AEA; 2-arachidonoylglycerol, 2AG) are endogenous neuromodulators that regulate presynaptic neurotransmitter release in neurons throughout the central and peripheral nervous systems. While substantial information is known about the eCBs, less is known about a number of endocannabinoid-like metabolites (eCBLs, e.g., N-palmitoylethanolamine, PEA; N-oleoylethanolamine, OEA). We report the comparative effects of parathion and chlorpyrifos on AChE and enzymes responsible for inactivation of the eCBs, fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL), and changes in the eCBs AEA and 2AG and eCBLs PEA and OEA, in rat striatum. Adult, male rats were treated with vehicle (peanut oil, 2 ml/kg, sc), parathion (27 mg/kg) or chlorpyrifos (280 mg/kg) 6-7 days after surgical implantation of microdialysis cannulae into the right striatum, followed by microdialysis two or four days later. Additional rats were similarly treated and sacrificed for evaluation of tissue levels of eCBs and eCBLs. Dialysates and tissue extracts were analyzed by LC-MS/MS. AChE and FAAH were extensively inhibited at both time-points (85-96%), while MAGL activity was significantly but lesser affected (37-62% inhibition) by parathion and chlorpyrifos. Signs of toxicity were noted only in parathion-treated rats. In general, chlorpyrifos increased eCB levels while parathion had no or lesser effects. Early changes in extracellular AEA, 2AG and PEA levels were significantly different between parathion and chlorpyrifos exposures. Differential changes in extracellular and/or tissue levels of eCBs and eCBLs could potentially influence a number of signaling pathways and contribute to selective neurological changes following acute OP intoxications. PMID:26215119

Comparative effects of parathion and chlorpyrifos on endocannabinoid and endocannabinoid-like lipid metabolites in rat striatum.

PubMed

Liu, Jing; Parsons, Loren; Pope, Carey

2015-09-01

Parathion and chlorpyrifos are organophosphorus insecticides (OPs) that elicit acute toxicity by inhibiting acetylcholinesterase (AChE). The endocannabinoids (eCBs, N-arachidonoylethanolamine, AEA; 2-arachidonoylglycerol, 2AG) are endogenous neuromodulators that regulate presynaptic neurotransmitter release in neurons throughout the central and peripheral nervous systems. While substantial information is known about the eCBs, less is known about a number of endocannabinoid-like metabolites (eCBLs, e.g., N-palmitoylethanolamine, PEA; N-oleoylethanolamine, OEA). We report the comparative effects of parathion and chlorpyrifos on AChE and enzymes responsible for inactivation of the eCBs, fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL), and changes in the eCBs AEA and 2AG and eCBLs PEA and OEA, in rat striatum. Adult, male rats were treated with vehicle (peanut oil, 2 ml/kg, sc), parathion (27 mg/kg) or chlorpyrifos (280 mg/kg) 6-7 days after surgical implantation of microdialysis cannulae into the right striatum, followed by microdialysis two or four days later. Additional rats were similarly treated and sacrificed for evaluation of tissue levels of eCBs and eCBLs. Dialysates and tissue extracts were analyzed by LC-MS/MS. AChE and FAAH were extensively inhibited at both time-points (85-96%), while MAGL activity was significantly but lesser affected (37-62% inhibition) by parathion and chlorpyrifos. Signs of toxicity were noted only in parathion-treated rats. In general, chlorpyrifos increased eCB levels while parathion had no or lesser effects. Early changes in extracellular AEA, 2AG and PEA levels were significantly different between parathion and chlorpyrifos exposures. Differential changes in extracellular and/or tissue levels of eCBs and eCBLs could potentially influence a number of signaling pathways and contribute to selective neurological changes following acute OP intoxications. Copyright © 2015 Elsevier Inc. All rights reserved.

A practical proposal for solving the world's cigarette butt problem: Recycling in fired clay bricks.

PubMed

Mohajerani, Abbas; Kadir, Aeslina Abdul; Larobina, Luke

2016-06-01

The disposal and littering of cigarette butts (CBs) is a serious environmental problem. Trillions of cigarettes are produced every year worldwide, resulting in millions of tonnes of toxic waste being dumped into the environment in the form of cigarette butts. As CBs have poor biodegradability, it can take many years for them to break down. This paper reviews and presents some of the results of a study on the recycling of CBs into fired clay bricks. Bricks with 2.5%, 5%, 7.5%, and 10% CB content by weight were manufactured and tested, and then compared against control clay bricks with 0% CB content. The results showed that the dry density decreased by up to 30% and the compressive strength decreased by 88% in bricks with 10% CBs. The calculated compressive strength of bricks with 1% CBs was determined to be 19.53Mpa. To investigate the effect of mixing time, bricks with 7.5% CB content were manufactured with different mixing times of 5, 10, and 15min. To test the effect of heating time on the properties of CB bricks, the heating rate used during manufacturing was changed to 0.7, 2, 5, and 10°Cmin(-1). Bricks with 0% and 5% CB content were fired with these heating rates. Leachate tests were carried out for bricks with 0%, 2.5%, 5%, and 10% CB content. The emissions released during firing were tested for bricks with 0% and 5% CB content using heating rates of 0.7, 2, 5, and 10°Cmin(-1). The gases tested were carbon monoxide (CO), carbon dioxide (CO2), chlorine (Cl2), nitrogen oxide (NO), and hydrogen cyanide (HCN). Finally, estimations were made for the energy that could be saved by firing bricks incorporating CBs. Calculations showed that up to 58% of the firing energy could potentially be saved. Bricks were shown to be a viable solution for the disposal of CBs. They can reduce contamination caused by cigarette butts and provide a masonry construction material that can be either loadbearing or non-loadbearing, depending on the quantity of CBs incorporated. This paper proposes the use of bricks with 1% CB content throughout the brick-manufacturing industry. If bricks contained as little as 1% CB content, they would still provide a solution for the issue of CB recycling while maintaining properties very similar to those of a non-CB brick. Our calculations show that, theoretically, only 2.5% of the world's annual brick production is necessary to completely offset the worldwide, annual cigarette production. Copyright © 2016 Elsevier Ltd. All rights reserved.

High-level ab initio predictions for the ionization energies and heats of formation of five-membered-ring molecules: thiophene, furan, pyrrole, 1,3-cyclopentadiene, and borole, C4H4X/C4H4X+ (X = S, O, NH, CH2, and BH).

PubMed

Lo, Po-Kam; Lau, Kai-Chung

2011-02-10

The ionization energies (IEs) and heats of formation (ΔH°(f0)/ΔH°(f298)) for thiophene (C(4)H(4)S), furan (C(4)H(4)O), pyrrole (C(4)H(4)NH), 1,3-cyclopentadiene (C(4)H(4)CH(2)), and borole (C(4)H(4)BH) have been calculated by the wave function-based ab initio CCSD(T)/CBS approach, which involves the approximation to the complete basis set (CBS) limit at the coupled-cluster level with single and double excitations plus a quasi-perturbative triple excitation [CCSD(T)]. Where appropriate, the zero-point vibrational energy correction (ZPVE), the core-valence electronic correction (CV), and the scalar relativistic effect (SR) are included in these calculations. The respective CCSD(T)/CBS predictions for C(4)H(4)S, C(4)H(4)O, C(4)H(4)NH, and C(4)H(4)CH(2), being 8.888, 8.897, 8.222, and 8.582 eV, are in excellent agreement with the experimental values obtained from previous photoelectron and photoion measurements. The ΔH°(f0)/ΔH°(f298) values for the aforementioned molecules and their corresponding cations have also been predicted by the CCSD(T)/CBS method, and the results are compared with the available experimental data. The comparisons between the CCSD(T)/CBS predictions and the experimental values for C(4)H(4)S, C(4)H(4)O, C(4)H(4)NH, and C(4)H(4)CH(2) suggest that the CCSD(T)/CBS procedure is capable of predicting reliable IE values for five-membered-ring molecules with an uncertainty of ±13 meV. In view of the excellent agreements between the CCSD(T)/CBS predictions and the experimental values for C(4)H(4)S, C(4)H(4)O, C(4)H(4)NH, and C(4)H(4)CH(2), the similar CCSD(T)/CBS IE and ΔH°(f0)/ΔH°(f298) predictions for C(4)H(4)BH, whose thermochemical data are not readily available due to its reactive nature, should constitute a reliable data set. The CCSD(T)/CBS IE(C(4)H(4)BH) value is 8.868 eV, and ΔH°(f0)/ΔH°(f298) values for C(4)H(4)BH and C(4)H(4)BH(+) are 269.5/258.6 and 1125.1/1114.6 kJ/mol, respectively. The highest occupied molecular orbitals (HOMO) of C(4)H(4)S, C(4)H(4)O, C(4)H(4)NH, C(4)H(4)CH(2), and C(4)H(4)BH have also been studied by the natural bond orbital (NBO) method, and the extent of π-electron delocalization in these five-membered rings are discussed in correlation with their molecular structures and orbitals.

News Source Use in the Crash of 1987: A Study of Four National Media.

ERIC Educational Resources Information Center

Lasorsa, Dominic L.; Reese, Stephen D.

1990-01-01

Examines coverage of the stock market crash in 1987 by CBS Evening News, "Newsweek," the "New York Times," and "Wall Street Journal." Finds that print media favored Wall Street sources whereas CBS favored government sources. Finds that news media favor high prestige sources and that use of different sources results in…

Genome Sequence of the Yeast Clavispora lusitaniae Type Strain CBS 6936.

PubMed

Durrens, Pascal; Klopp, Christophe; Biteau, Nicolas; Fitton-Ouhabi, Valérie; Dementhon, Karine; Accoceberry, Isabelle; Sherman, David J; Noël, Thierry

2017-08-03

Clavispora lusitaniae , an environmental saprophytic yeast belonging to the CTG clade of Candida , can behave occasionally as an opportunistic pathogen in humans. We report here the genome sequence of the type strain CBS 6936. Comparison with sequences of strain ATCC 42720 indicates conservation of chromosomal structure but significant nucleotide divergence. Copyright © 2017 Durrens et al.

Genome Sequence of the Yeast Clavispora lusitaniae Type Strain CBS 6936

PubMed Central

Klopp, Christophe; Biteau, Nicolas; Fitton-Ouhabi, Valérie; Dementhon, Karine; Accoceberry, Isabelle; Sherman, David J.; Noël, Thierry

2017-01-01

ABSTRACT Clavispora lusitaniae, an environmental saprophytic yeast belonging to the CTG clade of Candida, can behave occasionally as an opportunistic pathogen in humans. We report here the genome sequence of the type strain CBS 6936. Comparison with sequences of strain ATCC 42720 indicates conservation of chromosomal structure but significant nucleotide divergence. PMID:28774979

Rhodotorula portillonensis sp. nov., a basidiomycetous yeast isolated from Antarctic shallow-water marine sediment.

PubMed

Laich, Federico; Vaca, Inmaculada; Chávez, Renato

2013-10-01

During the characterization of the mycobiota associated with shallow-water marine environments from Antarctic sea, a novel pink yeast species was isolated. Sequence analysis of the D1/D2 domain of the LSU rDNA gene and 5.8S-ITS regions revealed that the isolated yeast was closely related to Rhodotorula pallida CBS 320(T) and Rhodotorula benthica CBS 9124(T). On the basis of morphological, biochemical and physiological characterization and phylogenetic analyses, a novel basidiomycetous yeast species, Rhodotorula portillonensis sp. nov., is proposed. The type strain is Pi2(T) ( = CBS 12733(T)  = CECT 13081(T)) which was isolated from shallow-water marine sediment in Fildes Bay, King George Island, Antarctica.

Role of hydrogen sulfide within the dorsal motor nucleus of the vagus in the control of gastric function in rats.

PubMed

Sun, H-Z; Yu, K-H; Ai, H-B

2015-05-01

Hydrogen sulfide (H2 S) is a gaseous messenger and serves as an important neuromodulator in the central nervous system. This study aimed to clarify the role of H2 S within the dorsal motor nucleus of the vagus (DMV) in the control of gastric function in rats. Cystathionine β-synthetase (CBS) is an important generator of endogenous H2 S in the brain. We investigated the distribution of CBS in the DMV using immunohistochemical method, and the effects of H2 S on gastric motility and on gastric acid secretion. CBS-immunoreactive (IR) neurons were detected in the rostral, intermediate and caudal DMV, with the highest number of CBS-IR neurons in the caudal DMV, and the lowest in the intermediate DMV. We also found that microinjection of the exogenous H2 S donor NaHS (0.04 and 0.08 mol/L; 0.1 μL; n = 6; p < 0.05) into the DMV significantly inhibited gastric motility with a dose-dependent trend, and promoted gastric acid secretion in Wistar rats. Microinjection of the same volume of physiological saline (PS; 0.1 μL, n = 6, p > 0.05) at the same location did not noticeably change gastric motility and acid secretion. The data from these experiments suggest that the CBS that produces H2 S is present in the DMV, and microinjection of NaHS into the DMV inhibited gastric motility and enhanced gastric acid secretion in rats. © 2015 John Wiley & Sons Ltd.

Cigarette Butt Decomposition and Associated Chemical Changes Assessed by 13C CPMAS NMR

PubMed Central

Bonanomi, Giuliano; Incerti, Guido; Cesarano, Gaspare; Gaglione, Salvatore A.; Lanzotti, Virginia

2015-01-01

Cigarette butts (CBs) are the most common type of litter on earth, with an estimated 4.5 trillion discarded annually. Apart from being unsightly, CBs pose a serious threat to living organisms and ecosystem health when discarded in the environment because they are toxic to microbes, insects, fish and mammals. In spite of the CB toxic hazard, no studies have addressed the effects of environmental conditions on CB decomposition rate. In this study we investigate the interactive effects of substrate fertility and N transfer dynamics on CB decomposition rate and carbon quality changes. We carried out an experiment using smoked CBs and wood sticks, used as a slow decomposing standard organic substrate, incubated in both laboratory and field conditions for two years. CB carbon quality changes during decomposition was assessed by 13C CPMAS NMR. Our experiment confirmed the low degradation rate of CBs which, on average, lost only 37.8% of their initial mass after two years of decomposition. Although a net N transfer occurred from soil to CBs, contrary to our hypothesis, mass loss in the medium-term (two years) was unaffected by N availability in the surrounding substrate. The opposite held for wood sticks, in agreement with the model that N-rich substrates promote the decomposition of other N-poor natural organic materials with a high C/N ratio. As regards CB chemical quality, after two years of decomposition 13C NMR spectroscopy highlighted very small changes in C quality that are likely to reflect a limited microbial attack. PMID:25625643

Symmetric corticobasal degeneration (S-CBD).

PubMed

Hassan, Anhar; Whitwell, Jennifer L; Boeve, Bradley F; Jack, Clifford R; Parisi, Joseph E; Dickson, Dennis W; Josephs, Keith A

2010-03-01

Corticobasal degeneration (CBD) is a neurodegenerative disease characterized pathologically by neuronal loss, gliosis and tau deposition in neocortex, basal ganglia and brainstem. Typical clinical presentation is known as corticobasal syndrome (CBS) and involves the core features of progressive asymmetric rigidity and apraxia, accompanied by other signs of cortical and extrapyramidal dysfunction. Asymmetry is also emphasized on neuroimaging. To describe a series of cases of CBD with symmetric clinical features and to compare clinical and imaging features of these symmetric CBD cases (S-CBD) to typical cases of CBS with CBD pathology. All cases of pathologically confirmed CBD from the Mayo Clinic Rochester database were identified. Clinical records were reviewed and quantitative volumetric analysis of symmetric atrophy on head MRI using atlas based parcellation was performed. Subjects were classified as S-CBD if no differences had been observed between right- and left-sided cortical or extrapyramidal signs or symptoms. S-CBD cases were compared to 10 randomly selected typical CBS cases. Five cases (2 female) met criteria for S-CBD. None had limb dystonia, myoclonus, apraxia or alien limb phenomena. S-CBD cases had significantly less asymmetric atrophy when compared with CBS cases (p=0.009); they were also younger at onset (median 61 versus 66 years, p<0.05) and death (67 versus 73 years, p<0.05). Family history was present in 40% of S-CBD cases. CBD can have a symmetric presentation, clinically and radiologically, in which typical features of CBS, such as limb apraxia, myoclonus, dystonia and alien limb phenomenon, may be absent. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

Effects of RAMEB and/or mechanical mixing on the bioavailability and biodegradation of PCBs in soil/slurry.

PubMed

Hu, Jinxing; Wang, Yalin; Su, Xiaomei; Yu, Chunna; Qin, Zhihui; Wang, Hui; Hashmi, Muhammad Z; Shi, Jiyan; Shen, Chaofeng

2016-07-01

Microbial remediation is preferred as a clean and cost-effective method for restoring environments polluted by organics. But the biodegradation rates of hydrophobic organic contaminants (HOCs) are usually extremely restricted by their low bioavailability, especially in soil. Here, a physical method (mechanical mixing) and a chemical method (randomly methylated-β-cyclodextrins, RAMEB) were adopted to improve the bioavailability and biodegradation of polychlorinated biphenyls (PCBs) of an aged soil. The bioavailability of tri-CBs was increased by adding RAMEB in soil/slurry or assisting mechanical mixing in slurry, but these methods had no effects on the bioavailability of tetra-CBs and high chlorinated PCBs (Cl > 4). The degradation rate of tri-CBs could be obviously enhanced by adding RAMEB in soil or assisting mechanical mixing in slurry. The highest removal amount of tri-CBs reached 43.8% in 100 d with a first-order decay kinetics constant of 0.0059 d(-1). But the removal of tetra-CBs and high chlorinated PCBs (Cl > 4) were not significant in all mesocosms, possibly due to the lack or weakness of the native degrading microflora. Based on the analysis of the richness and diversity of bacterial communities, the characteristics of the heatmap and the variation of bphC copy numbers in the soil/slurry mesocosms, it could be inferred that there was no obvious corresponding relationship between the variation of the bacterial communities and the physical/chemical measures. Copyright © 2016 Elsevier Ltd. All rights reserved.

Cytologic assessment of estrogen receptor, progesterone receptor, and HER2 status in metastatic breast carcinoma.

PubMed

Pareja, Fresia; Murray, Melissa P; Jean, Ryan Des; Konno, Fumiko; Friedlander, Maria; Lin, Oscar; Edelweiss, Marcia

2017-01-01

Discordance in the receptor status between primary breast carcinomas (PBC) and corresponding metastasis is well documented. Interrogation of the receptor status of metastatic breast carcinoma (MBC) in cytology material is common practice; however, its utility has not been thoroughly validated. We studied patients with MBC, and evaluated the concordance rates of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) between PBC surgical specimens and corresponding MBC cell blocks (CBs). We correlated the findings with clinicopathologic variables and with the fixation methods used. We searched for patients with MBC diagnosed on cytology from 2007 to 2009 and selected those with ER, PR and HER2 tested in both the PBC surgical specimens and the MBC CBs. We included CBs fixed in formalin and methanol based solution (CytoLyt®). All slides were reevaluated by cytopathologists. Clinical information was retrieved from the medical records. We studied 65 patients with PBC and MBC paired specimens. The concordance rates between PBC and MBC were 78.5%, 58.5% and 96.9%, for ER, PR and HER2, respectively. When discordant, PR status switched from positive (PBC) to negative (MBC) in most cases (23/27). The PR concordance rate was 45.2% for CBs fixed in formalin and 70.6% for those fixed with CytoLyt® (p=0.047). The ER, PR and HER2 concordance rates between the PBC and MBC CBs are similar to those reported in paired surgical specimens. PR status was the most prevalent discordance and was not accompanied by a switch in ER.

Ionization potential and electron affinity for six common explosive compounds by DFT, MP2, and CBS-QB3

DOE PAGES

Cooper, Jason K.; Grant, Christian D.; Zhang, Jin Z.

2012-07-20

The vertical and adiabatic ionization potential (IP V and IP A) and vertical electron affinity (EA V) for six explosives (RDX, HMX, TNT, PETN, HMTD, and TATP) have been studied by ab initio computational methods. The IPV was calculated using MP2 and CBS-QB3 while the IP A was calculated with B3LYP, CAM-B3LYP, ω B97XD, B2PLYP, and MP2. RDX and TNT IP A’s were also reported using CBS -QB3. Excluding results by CBS-QB3, B3LYP and B2PLYPD provided superior and more consistent results for calculating the IP. The EA V were calculated using the same methods however B3LYP performed the worst inmore » this case with MP2 and B2PLYPD predicting values closest to those made by CBS-QB3, which was used a reference due to lacking experimental data. Basis set effects were evaluated using 6- 31+G(d,p), 6-311+G(d,p), and 6-311+(3df,2p) for both IP and EA. 6-31+G(d,p) gave satisfactory results for calculating both IP however 6-311+G(3df,2p) had improved results in calculating the EA. The four nitro containing compounds had exothermic reduction potentials while the peroxides were unfavorable. Additionally, it was seen that RDX, HMX, TATP and HMTD were unstable in their reduced forms. Results are aimed to assist detection and screening methods.« less

Description of Martiniozyma gen. nov. and transfer of seven Candida species to Saturnispora as new combinations

USDA-ARS?s Scientific Manuscript database

DNA sequence analysis has shown Candida abiesophila (NRRL Y-11514T, CBS 5366T) and Candida asiatica (NRRL Y-63747T, CBS 10863T) to be members of a small clade that is phylogenetically separate from other yeasts. In view of their isolation from neighboring genera, such as Pichia and Saturnispora, the...

Towards Inclusion of Cross-Boundary Students from Mainland China in Educational Policies and Practices in Hong Kong

ERIC Educational Resources Information Center

Yuen, Celeste Yuet-Mui

2011-01-01

Every society has an obligation to provide quality education to children regardless of their socio-economic and cultural backgrounds. The number of cross-boundary students (CBS) from Mainland China in Hong Kong schools is increasing. This article reviews educational policy and provision for educating CBS, presenting data from an empirical study.…

What Factors Predict Middle School Students Sign Up for Washington's College Bound Scholarship Program? A Mixed Methods Evaluation. Working Paper 175

ERIC Educational Resources Information Center

Goldhaber, Dan; Long, Mark C.; Person, Ann E.; Rooklyn, Jordan

2017-01-01

We investigate factors influencing student sign-ups for Washington State's College Bound Scholarship (CBS) program. We find a substantial share of eligible middle school students fail to sign the CBS, forgoing college financial aid. Student characteristics associated with signing the scholarship parallel characteristics of low-income students who…

Endocannabinoid signaling at the periphery: 50 years after THC

PubMed Central

Maccarrone, Mauro; Bab, Itai; Bíró, Tamás; Cabral, Guy A.; Dey, Sudhansu K.; Di Marzo, Vincenzo; Konje, Justin C.; Kunos, George; Mechoulam, Raphael; Pacher, Pal; Sharkey, Keith A.; Zimmer, Andreas

2015-01-01

Fifty years ago (in 1964) the psychoactive ingredient of Cannabis sativa, Δ9-tetrahydrocannabinol (THC), was isolated. Nearly 30 years later the endogenous counterparts of THC, collectively termed endocannabinoids (eCBs), were discovered: N-arachidonoylethanolamine (anandamide, AEA) in 1992, and 2-arachidonoylglycerol (2-AG) in 1995. Since then, considerable research has shed light on the impact of eCBs on human health and disease, identifying an ensemble of proteins that bind, synthesize and degrade them, and that altogether form the eCB system. eCBs control basic biological processes, including cell-choice between survival and death, and progenitor/stem cell proliferation and differentiation. Not surprisingly, in the past two decades, eCBs have been recognized as key mediators of several aspects of human pathophysiology, and thus have emerged among the most widespread and versatile signaling molecules ever discovered. Here, some of the pioneers of this research field review the state-of-the-art of critical eCB functions in peripheral organs. Our community effort is aimed at establishing consensus views on the relevance of the peripheral eCB system for human health and disease pathogenesis, as well as to highlight emerging challenges and therapeutic hopes. PMID:25796370

Endocannabinoid signaling at the periphery: 50 years after THC.

PubMed

Maccarrone, Mauro; Bab, Itai; Bíró, Tamás; Cabral, Guy A; Dey, Sudhansu K; Di Marzo, Vincenzo; Konje, Justin C; Kunos, George; Mechoulam, Raphael; Pacher, Pal; Sharkey, Keith A; Zimmer, Andreas

2015-05-01

In 1964, the psychoactive ingredient of Cannabis sativa, Δ(9)-tetrahydrocannabinol (THC), was isolated. Nearly 30 years later the endogenous counterparts of THC, collectively termed endocannabinoids (eCBs), were discovered: N-arachidonoylethanolamine (anandamide) (AEA) in 1992 and 2-arachidonoylglycerol (2-AG) in 1995. Since then, considerable research has shed light on the impact of eCBs on human health and disease, identifying an ensemble of proteins that bind, synthesize, and degrade them and that together form the eCB system (ECS). eCBs control basic biological processes including cell choice between survival and death and progenitor/stem cell proliferation and differentiation. Unsurprisingly, in the past two decades eCBs have been recognized as key mediators of several aspects of human pathophysiology and thus have emerged to be among the most widespread and versatile signaling molecules ever discovered. Here some of the pioneers of this research field review the state of the art of critical eCB functions in peripheral organs. Our community effort is aimed at establishing consensus views on the relevance of the peripheral ECS for human health and disease pathogenesis, as well as highlighting emerging challenges and therapeutic hopes. Copyright © 2015 Elsevier Ltd. All rights reserved.

Candida spencermartinsiae sp. nov., Candida taylorii sp. nov. and Pseudozyma abaconensis sp. nov., novel yeasts from mangrove and coral reef ecosystems.

PubMed

Statzell-Tallman, Adele; Scorzetti, Gloria; Fell, Jack W

2010-08-01

Three species of yeasts are taxonomically described for strains isolated from marine environments. Candida spencermartinsiae sp. nov. (type strain CBS 10894T =NRRL Y-48663T) and Candida taylorii sp. nov. (type strain CBS 8508T =NRRL Y-27213T) are anamorphic ascomycetous yeasts in a phylogenetic cluster of marine yeasts in the Debaryomyces/Lodderomyces clade of the Saccharomycetales. The two species were isolated from multiple locations among coral reefs and mangrove habitats. Pseudozyma abaconensis sp. nov. (type strain CBS 8380T =NRRL Y-17380T) is an anamorphic basidiomycete that is related to the smut fungi of the genus Ustilago in the Ustilaginales. P. abaconensis was collected from waters adjacent to a coral reef.

Flow-diverter in radiation-induced skull base carotid blowout syndrome: do not write it off!

PubMed

Anil, Gopinathan; Zhang, Junwei; Ong, Yew Kwang; Hui, Francis

2017-10-01

Post-radiotherapy carotid blowout syndrome (CBS) of the skull base is a rare but often catastrophic complication of head and neck malignancies. The existing literature on the treatment of this condition with flow-diverting devices (FDD) is extremely limited and disappointing. We present a case of impending CBS in a patient previously irradiated for nasopharyngeal cancer that was successfully treated with use of multiple FDDs, adjunctive endonasal packing and delayed reinforcement with pedicled naso-septal flap, yielding an excellent outcome at 14-months follow-up. Notwithstanding the discouraging results in literature, our anecdotal experience suggests that endovascular reconstruction using FDD could be an option with long-term viability in post-radiotherapy CBS involving the skull base when reinforced with a vascularised naso-septal flap.

Description of Groenewaldozyma gen. nov. for placement of Candida auringiensis, Candida salmanticensis and Candida tartarivorans.

PubMed

Kurtzman, Cletus P

2016-07-01

DNA sequence analyses have demonstrated that species of the polyphyletic anamorphic ascomycete genus Candida may be members of described teleomorphic genera, members of the Candida tropicalis clade upon which the genus Candida is circumscribed, or members of isolated clades that represent undescribed genera. From phylogenetic analysis of gene sequences from nuclear large subunit rRNA, mitochondrial small subunit rRNA and cytochrome oxidase II, Candida auringiensis (NRRL Y-17674(T), CBS 6913(T)), Candida salmanticensis (NRRL Y-17090(T), CBS 5121(T)), and Candida tartarivorans (NRRL Y-27291(T), CBS 7955(T)) were shown to be members of an isolated clade and are proposed for reclassification in the genus Groenewaldozyma gen. nov. (MycoBank MB 815817). Neighbouring taxa include species of the Wickerhamiella clade and Candida blankii.

Theoretical prediction of the ionization energies of the C4H7 radicals: 1-methylallyl, 2-methylallyl, cyclopropylmethyl, and cyclobutyl radicals.

PubMed

Lau, Kai-Chung; Zheng, Wenxu; Wong, Ning-Bew; Li, Wai-Kee

2007-10-21

The ionization energies (IEs) for the 1-methylallyl, 2-methylallyl, cyclopropylmethyl, and cyclobutyl radicals have been calculated by the wave function based ab initio CCSD(T)/CBS approach, which involves the approximation to the complete basis set (CBS) limit at the coupled cluster level with single and double excitations plus quasiperturbative triple excitation [CCSD(T)]. The zero-point vibrational energy correction, the core-valence electronic correction, and the scalar relativistic effect correction are included in these calculations. The present CCSD(T)/CBS results are then compared with the IEs determined in the photoelectron experiment by Schultz et al. [J. Am. Chem. Soc. 106, 7336 (1984)] The predicted IE value (7.881 eV) of 2-methylallyl radical is found to compare very favorably with the experimental value of 7.90+/-0.02 eV. Two ionization transitions for cis-1-methylallyl and trans-1-methylallyl radicals have been considered here. The comparison between the predicted IE values and the previous measurements shows that the photoelectron peak observed by Schultz et al. likely corresponds to the adiabatic ionization transition for the trans-1-methylallyl radical to form trans-1-methylallyl cation. Although a precise IE value for the cyclopropylmethyl radical has not been directly determined, the experimental value deduced indirectly using other known energetic data is found to be in good accord with the present CCSD(T)/CBS prediction. We expect that the Franck-Condon factor for ionization transition of c-C4H7-->bicyclobutonium is much less favorable than that for ionization transition of c-C4H7-->planar-C4H7+, and the observed IE in the previous photoelectron experiment is likely due to the ionization transition for c-C4H7-->planar-C4H7+. Based on our CCSD(T)/CBS prediction, the ionization transition of c-C4H7-->bicyclobutonium with an IE value around 6.92 eV should be taken as the adiabatic ionization transition for the cyclobutyl radical. The present study provides support for the conclusion that the CCSD(T)/CBS approach with high-level energetic corrections can be used to provide reliable IE predictions for C4 hydrocarbon radicals with an uncertainty of +/-22 meV. The CCSD(T)/CBS predictions to the heats of formation for the aforementioned radicals and cations are also presented.

Cystathionine metabolic enzymes play a role in the inflammation resolution of human keratinocytes in response to sub-cytotoxic formaldehyde exposure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Eunyoung

Low-level formaldehyde exposure is inevitable in industrialized countries. Although daily-life formaldehyde exposure level is practically impossible to induce cell death, most of mechanistic studies related to formaldehyde toxicity have been performed in cytotoxic concentrations enough to trigger cell death mechanism. Currently, toxicological mechanisms underlying the sub-cytotoxic exposure to formaldehyde are not clearly elucidated in skin cells. In this study, the genome-scale transcriptional analysis in normal human keratinocytes (NHKs) was performed to investigate cutaneous biological pathways associated with daily life formaldehyde exposure. We selected the 175 upregulated differentially expressed genes (DEGs) and 116 downregulated DEGs in NHKs treated with 200 μMmore » formaldehyde. In the Gene Ontology (GO) enrichment analysis of the 175 upregulated DEGs, the endoplasmic reticulum (ER) unfolded protein response (UPR) was identified as the most significant GO biological process in the formaldeyde-treated NHKs. Interestingly, the sub-cytotoxic formaldehyde affected NHKs to upregulate two enzymes important in the cellular transsulfuration pathway, cystathionine γ-lyase (CTH) and cystathionine-β-synthase (CBS). In the temporal expression analysis, the upregulation of the pro-inflammatory DEGs such as MMP1 and PTGS2 was detected earlier than that of CTH, CBS and other ER UPR genes. The metabolites of CTH and CBS, L-cystathionine and L-cysteine, attenuated the formaldehyde-induced upregulation of pro-inflammatory DEGs, MMP1, PTGS2, and CXCL8, suggesting that CTH and CBS play a role in the negative feedback regulation of formaldehyde-induced pro-inflammatory responses in NHKs. In this regard, the sub-cytotoxic formaldehyde-induced CBS and CTH may regulate inflammation fate decision to resolution by suppressing the early pro-inflammatory response. - Highlights: • Sub-cytotoxic formaldehyde upregulates ER UPR-associated genes in NHKs. • Formaldehyde-induced ER UPR genes includes cystathionine γ-lyase (CTH). • Sub-cytotoxic formaldehyde upregulates cystathionine-β-synthase (CBS) in NHKs. • Cystathionine metabolic enzymes may attenuate formaldehyde-induced inflammation in NHKs. • Cystathionine metabolic enzymes may play a role in the resolution of inflammation in NHKs.« less

Counting or Chunking?

PubMed Central

Spotorno, Nicola; McMillan, Corey T.; Powers, John P.; Clark, Robin; Grossman, Murray

2014-01-01

A growing amount of empirical data is showing that the ability to manipulate quantities in a precise and efficient fashion is rooted in cognitive mechanisms devoted to specific aspects of numbers processing. The Analog number system (ANS) has a reasonable representation of quantities up to about 4, and represents larger quantities on the basis of a numerical ratio between quantities. In order to represent the precise cardinality of a number, the ANS may be supported by external algorithms such as language, leading to a “Precise Number System”. In the setting of limited language, other number-related systems can appear. For example the Parallel Individuation system (PIS) supports a “chunking mechanism” that clusters units of larger numerosities into smaller subsets. In the present study we investigated number processing in non-aphasic patients with Corticobasal Syndrome (CBS) and Posterior Cortical Atrophy (PCA), two neurodegenerative conditions that are associated with progressive parietal atrophy. The present study investigated these number systems in CBS and PCA by assessing the property of the ANS associated with smaller and larger numerosities, and the chunking property of the PIS. The results revealed that CBS/PCA patients are impaired in simple calculations (e.g., addition and subtraction) and that their performance strongly correlates with the size of the numbers involved in these calculations, revealing a clear magnitude effect. This magnitude effect correlated with gray matter atrophy in parietal regions. Moreover, a numeral-dots transcoding task showed that CBS/PCA patients are able to take advantage of clustering in the spatial distribution of the dots of the array. The relative advantage associated with chunking compared to a random spatial distribution correlated with both parietal and prefrontal regions. These results shed light on the properties of systems for representing number knowledge in non-aphasic patients with CBS and PCA. PMID:25278132

Reduced Expression of Hydrogen Sulfide-Generating Enzymes Down-Regulates 15-Hydroxyprostaglandin Dehydrogenase in Chorion during Term and Preterm Labor.

PubMed

Sun, Qianqian; Chen, Zixi; He, Ping; Li, Yuan; Ding, Xiaoying; Huang, Ying; Gu, Hang; Ni, Xin

2018-01-01

Chorionic NAD-dependent 15-hydroxyprostaglandin dehydrogenase (PGDH) plays a pivotal role in controlling the amount of prostaglandins in the uterus and has been implicated in the process of labor. Prior studies identified hydrogen sulfide-generating enzymes cystathionine-β-synthetase (CBS) and cystathionine-γ-lyase (CSE) in fetal membranes. We investigated whether hydrogen sulfide is involved in the regulation of PGDH expression in the chorion during labor. The chorionic tissues were obtained from pregnant women at preterm in labor and at term in labor or not in labor at term. Levels of CSE and CBS and hydrogen sulfide production rate were down-regulated in term in labor and preterm in labor groups compared with not in labor at term group. The CBS level correlated to PGDH expression in the chorion. Hydrogen sulfide donor NaHS and precursor l-cysteine dose-dependently stimulated PGDH expression and activity in cultured chorionic trophoblasts. The effect of l-cysteine was blocked by CBS inhibitor and CBS siRNA but not by CSE inhibitor and CSE siRNA. Hydrogen sulfide treatment suppressed miR-26b and miR-199a expression in chorionic trophoblasts. miR-26b and miR-199a mimics blocked hydrogen sulfide upregulation of PGDH expression. Our results indicate that hydrogen sulfide plays pivotal roles in maintenance of PGDH expression in the chorion during human pregnancy. Reduced expression of hydrogen sulfide-generating enzymes contributes to an increased amount of prostaglandins in the uterus during labor. Copyright © 2018 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

The nature of working memory for Braille.

PubMed

Cohen, Henri; Voss, Patrice; Lepore, Franco; Scherzer, Peter

2010-05-26

Blind individuals have been shown on multiple occasions to compensate for their loss of sight by developing exceptional abilities in their remaining senses. While most research has been focused on perceptual abilities per se in the auditory and tactile modalities, recent work has also investigated higher-order processes involving memory and language functions. Here we examined tactile working memory for Braille in two groups of visually challenged individuals (completely blind subjects, CBS; blind with residual vision, BRV). In a first experimental procedure both groups were given a Braille tactile memory span task with and without articulatory suppression, while the BRV and a sighted group performed a visual version of the task. It was shown that the Braille tactile working memory (BrWM) of CBS individuals under articulatory suppression is as efficient as that of sighted individuals' visual working memory in the same condition. Moreover, the results suggest that BrWM may be more robust in the CBS than in the BRV subjects, thus pointing to the potential role of visual experience in shaping tactile working memory. A second experiment designed to assess the nature (spatial vs. verbal) of this working memory was then carried out with two new CBS and BRV groups having to perform the Braille task concurrently with a mental arithmetic task or a mental displacement of blocks task. We show that the disruption of memory was greatest when concurrently carrying out the mental displacement of blocks, indicating that the Braille tactile subsystem of working memory is likely spatial in nature in CBS. The results also point to the multimodal nature of working memory and show how experience can shape the development of its subcomponents.

The Nature of Working Memory for Braille

PubMed Central

Cohen, Henri; Voss, Patrice; Lepore, Franco; Scherzer, Peter

2010-01-01

Blind individuals have been shown on multiple occasions to compensate for their loss of sight by developing exceptional abilities in their remaining senses. While most research has been focused on perceptual abilities per se in the auditory and tactile modalities, recent work has also investigated higher-order processes involving memory and language functions. Here we examined tactile working memory for Braille in two groups of visually challenged individuals (completely blind subjects, CBS; blind with residual vision, BRV). In a first experimental procedure both groups were given a Braille tactile memory span task with and without articulatory suppression, while the BRV and a sighted group performed a visual version of the task. It was shown that the Braille tactile working memory (BrWM) of CBS individuals under articulatory suppression is as efficient as that of sighted individuals' visual working memory in the same condition. Moreover, the results suggest that BrWM may be more robust in the CBS than in the BRV subjects, thus pointing to the potential role of visual experience in shaping tactile working memory. A second experiment designed to assess the nature (spatial vs. verbal) of this working memory was then carried out with two new CBS and BRV groups having to perform the Braille task concurrently with a mental arithmetic task or a mental displacement of blocks task. We show that the disruption of memory was greatest when concurrently carrying out the mental displacement of blocks, indicating that the Braille tactile subsystem of working memory is likely spatial in nature in CBS. The results also point to the multimodal nature of working memory and show how experience can shape the development of its subcomponents. PMID:20520807

High-level ab initio calculations for the four low-lying families of minima of (H2O)(20): 1. Estimates of MP2/CBS binding energies and comparison with empirical potentials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fanourgakis, Georgios S.; Apra, Edoardo; Xantheas, Sotiris S.

2004-08-08

We report estimates of complete basis set (CBS) limits at the second-order Møller-Plesset perturbation level of theory (MP2) for the binding energies of the lowest lying isomers within each of the four major families of minima of (H2O)20. These were obtained by performing MP2 calculations with the family of correlation-consistent basis sets up to quadruple zeta quality, augmented with additional diffuse functions (aug-cc-pVnZ, n=D, T, Q). The MP2/CBS estimates are: -200.1 kcal/mol (dodecahedron, 30 hydrogen bonds), -212.6 kcal/mol (fused cubes, 36 hydrogen bonds), -215.0 (face-sharing pentagonal prisms, 35 hydrogen bonds) and –217.9 kcal/mol (edge-sharing pentagonal prisms, 34 hydrogen bonds). Themore » energetic ordering of the various (H2O)20 isomers does not follow monotonically the number of hydrogen bonds as in the case of smaller clusters such as the different isomers of the water hexamer. The dodecahedron lies ca. 18 kcal/mol higher in energy than the most stable edge-sharing pentagonal prism isomer. The TIP4P, ASP-W4, TTM2-R, AMOEBA and TTM2-F empirical potentials also predict the energetic stabilization of the edge-sharing pentagonal prisms with respect to the dodecahedron, albeit they universally underestimate the cluster binding energies with respect to the MP2/CBS result. Among them, the TTM2-F potential was found to predict the absolute cluster binding energies to within < 1% from the corresponding MP2/CBS values, whereas the error for the rest of the potentials considered in this study ranges from 3-5%.« less

Assessing the dysexecutive syndrome in dementia.

PubMed

Gansler, David A; Huey, Edward D; Pan, Jessica J; Wasserman, Eric; Grafman, Jordan H

2017-03-01

We compared performance on tests of dysexecutive behaviour (DB) and executive function (EF) in patients with behavioural variant frontotemporal dementia (bvFTD), primary progressive aphasia (PPA) and corticobasal syndrome (CBS). Patients diagnosed with bvFTD (n=124), PPA (n=34) and CBS (n=85) were recruited. EF was measured with the Delis-Kaplan Executive Function System (DKEFS: performance based), and DB was measured with the Frontal Systems Behavior Scale (FrSBe: caregiver-report based). Confirmatory factor analysis characterised the relationship between EF and DB, binary logistic regression evaluated the incremental diagnostic utility of the measures and neuroimaging data from 110 patients identified neural correlates. EF was lowest and DB was highest in bvFTD participants. EF and DB were distinct but related (r=-0.48). Measures correctly classified 89% of bvFTD from CBS patients and 93% of bvFTD from PPA patients-30% and 13% above base rates (59%, 80%), respectively. All modalities were useful in identifying CBS and PPA, whereas DB alone was useful for identifying bvFTD. EF was uniquely associated with caudal left dorsolateral prefrontal and lateral temporo-parietal cortices. DB was uniquely associated with the cingulate (R>L), right subcallosal and right anterior frontal cortex. EF and DB were associated with the rostral dorsolateral prefrontal cortex bilaterally. EF and DB measures displayed criterion and construct validity, had incremental utility at low DB levels (CBS and PPA) and were associated with overlapping and distinct neural correlates. EF and DB procedures can conjointly provide useful diagnostic and descriptive information in identifying and ruling out the dysexecutive syndrome. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Polychlorinated biphenyls in Nepalese surface soils: Spatial distribution, air-soil exchange, and soil-air partitioning.

PubMed

Yadav, Ishwar Chandra; Devi, Ningombam Linthoingambi; Li, Jun; Zhang, Gan

2017-10-01

Regardless of the ban on the polychlorinated biphenyls (PCBs) decade ago, significant measures of PCBs are still transmitted from essential sources in cities and are all inclusive ecological contaminants around the world. In this study, the concentrations of PCBs in soil, the air-soil exchange of PCBs, and the soil-air partitioning coefficient (K SA ) of PCBs were investigated in four noteworthy urban areas in Nepal. Overall, the concentrations of ∑ 30 PCBs ranged from 10 to 59.4ng/g dry weight; dw (mean 12.2ng/g ±11.2ng/g dw). The hexa-CBs (22-31%) was most dominant among several PCB-homologues, followed by tetra-CBs (20-29%), hepta-CBs (12-21%), penta-CBs (15-17%) and tri-CBs (9-19%). The sources of elevated level of PCBs discharge in Nepalese soil was identified as emission from transformer oil, lubricants, breaker oil, cutting oil and paints, and cable insulation. Slightly strong correlation of PCBs with TOC than BC demonstrated that amorphous organic matter (AOM) assumes a more critical part in holding of PCBs than BC in Nepalese soil. The fugacity fraction (ff) results indicated the soil being the source of PCB in air through volatilization and net transport from soil to air. The soil-air partitioning coefficient study suggests the absorption by soil organic matter control soil-air partitioning of PCBs. Slightly weak but positive correlation of measured Log K SA with Log K OA (R 2 = 0.483) and Log K BC-A (R 2 = 0.438) suggests that both Log K OA and Log K BC-A can predict soil-air partitioning to lesser extent for PCBs. Copyright © 2017 Elsevier Inc. All rights reserved.

Impaired Heme Binding and Aggregation of Mutant Cystathionine β-Synthase Subunits in Homocystinuria

PubMed Central

Janošík, Miroslav; Oliveriusová, Jana; Janošíková, Bohumila; Sokolová, Jitka; Kraus, Eva; Kraus, Jan P.; Kožich, Viktor

2001-01-01

During the past 20 years, cystathionine β-synthase (CBS) deficiency has been detected in the former Czechoslovakia with a calculated frequency of 1:349,000. The clinical manifestation was typical of homocystinuria, and about half of the 21 patients were not responsive to pyridoxine. Twelve distinct mutations were detected in 30 independent homocystinuric alleles. One half of the alleles carried either the c.833 T→C or the IVS11−2A→C mutation; the remaining alleles contained private mutations. The abundance of five mutant mRNAs with premature stop codons was analyzed by PCR-RFLP. Two mRNAs, c.828_931ins104 (IVS7+1G→A) and c.1226 G→A, were severely reduced in the cytoplasm as a result of nonsense-mediated decay. In contrast, the other three mRNAs—c.19_20insC, c.28_29delG, and c.210_235del26 (IVS1−1G→C)—were stable. Native western blot analysis of 14 mutant fibroblast lines showed a paucity of CBS antigen, which was detectable only in aggregates. Five mutations—A114V (c.341C→T), A155T (c.463G→A), E176K (c.526G→A), I278T (c.833T→C), and W409_G453del (IVS11−2A→C)—were expressed in Escherichia coli. All five mutant proteins formed substantially more aggregates than did the wild-type CBS, and no aggregates contained heme. These data suggest that abnormal folding, impaired heme binding, and aggregation of mutant CBS polypeptides may be common pathogenic mechanisms in CBS deficiency. PMID:11359213

Are surgery training programs ready for virtual reality? A survey of program directors in general surgery.

PubMed

Haluck, R S; Marshall, R L; Krummel, T M; Melkonian, M G

2001-12-01

The use of advanced technology, such as virtual environments and computer-based simulators (VR/CBS), in training has been well established by both industry and the military. In contrast the medical profession, including surgery, has been slow to incorporate such technology in its training. In an attempt to identify factors limiting the regular incorporation of this technology into surgical training programs, a survey was developed and distributed to all general surgery program directors in the United States. A 22-question survey was sent to 254 general surgery program directors. The survey was designed to reflect attitudes of the program directors regarding the use of computer-based simulation in surgical training. Questions were scaled from 1 to 5 with 1 = strongly disagree and 5 = strongly agree. A total of 139 responses (55%) were returned. The majority of respondents (58%) had seen VR/CBS, but only 19% had "hands-on" experience with these systems. Respondents strongly agreed that there is a need for learning opportunities outside of the operating room and a role for VR/CBS in surgical training. Respondents believed both staff and residents would support this type of training. Concerns included VR/CBS' lack of validation and potential requirements for frequent system upgrades. Virtual environments and computer-based simulators, although well established training tools in other fields, have not been widely incorporated into surgical education. Our results suggest that program directors believe this type of technology would be beneficial in surgical education, but they lack adequate information regarding VR/CBS. Developers of this technology may need to focus on educating potential users and addressing their concerns.

Recovery of fermented inulin fiber by lactic acid bacteria (LAB) from inulin hydrolysate using fungi inulinase enzymes of Scopulariopsis sp.-CBS1 and class of Deuteromycetes-CBS4 as cholesterol binder

NASA Astrophysics Data System (ADS)

Susilowati, Agustine; Melanie, Hakiki; Maryati, Yati; Aspiyanto

2017-01-01

Fermentation of Lactobacillus Acid Bacteria (LAB) which are mixtures of Lactobacillus acidophilus, Bifidobacteriumbifidum, Lactobacillus bulgaricus and Streptococcus thermophillus on hydrolysate as a result of inulin hydrolysis using inulinase enzymes obtained from endophytic fungi ofScopulariopsis sp.-CBS1 (inulin hydrolysate of S) and Class of Deuteromycetes-CBS4 (inulin hydrolysate of D) generate potential fermented inulin fiber as cholesterol binder. Fermentation process was conducted under concentrations of inulin hydrolysate 50% (w/v), LAB 15% (v/v) and skim milk 12.5% (w/v) at room temperature and 40°C for 0, 12, 24, 36 and 48 hours, respectively. Result of experimental work showed that longer time of LAB fermentation increased total acids, TPC and CBC at pH 2, but decreased total sugar, reducing, IDF, SDF, CBC pH 2 and CBC pH 7. Based on Cholesterol Binding Capacity (CBC), optimization of fermentation process on inulin hydrolysate of S was achieved by combining treatment at 40°C for 24 hours resulted in CBC pH 2 of 19.11 mg/g TDF and inulin hydrolysate of D was achieved by fermentation at 40 °C for 48 hours resulted in CBC pH 2 of 24.28 mg/g TDF. Inulin hydrolysate of class of Deutrymecetes CBS4 fermented by LAB had better functional property as cholesterol binder than that inulin hydrolysate of S fermented by LAB. This is due to cholesterol binder and cholesterol derivatives as a result of degradation of LAB on digestive system (stomach) when compared to higher colon under optimal process condition.

Size distribution and sorption of polychlorinated biphenyls during haze episodes

NASA Astrophysics Data System (ADS)

Zhu, Qingqing; Liu, Guorui; Zheng, Minghui; Zhang, Xian; Gao, Lirong; Su, Guijin; Liang, Yong

2018-01-01

There is a lack of studies on the size distribution of polychlorinated biphenyls (PCBs) during haze days, and their sorption mechanisms on aerosol particles remain unclear. In this study, PCBs in particle-sized aerosols from urban atmospheres of Beijing, China were investigated during haze and normal days. The concentrations, gas/particle partitioning, size distribution, and associated human daily intake of PCBs via inhalation were compared during haze days and normal days. Compared with normal days, higher particle mass-associated PCB levels were measured during haze days. The concentrations of ∑PCBs in particulate fractions were 11.9-134 pg/m3 and 6.37-14.9 pg/m3 during haze days and normal days, respectively. PCBs increased with decreasing particle size (>10 μm, 10-2.5 μm, 2.5-1.0 μm, and ≤1.0 μm). During haze days, PCBs were overwhelmingly associated with a fine particle fraction of ≤1.0 μm (64.6%), while during normal days the contribution was 33.7%. Tetra-CBs were the largest contributors (51.8%-66.7%) both in the gas and particle fractions during normal days. The profiles in the gas fraction were conspicuously different than those in the PM fractions during haze days, with di-CBs predominating in the gas fraction and higher homologues (tetra-CBs, penta-CBs, and hexa-CBs) concurrently accounting for most of the PM fractions. The mean-normalized size distributions of particulate mass and PCBs exhibited unimodal patterns, and a similar trend was observed for PCBs during both days. They all tended to be in the PM fraction of 1.0-2.5 μm. Adsorption might be the predominating mechanism for the gas-particle partitioning of PCBs during haze days, whereas absorption might be dominative during normal days.

Frazzled/DCC facilitates cardiac cell outgrowth and attachment during Drosophila dorsal vessel formation.

PubMed

Macabenta, Frank D; Jensen, Amber G; Cheng, Yi-Shan; Kramer, Joseph J; Kramer, Sunita G

2013-08-15

Drosophila embryonic dorsal vessel (DV) morphogenesis is a highly stereotyped process that involves the migration and morphogenesis of 52 pairs of cardioblasts (CBs) in order to form a linear tube. This process requires spatiotemporally-regulated localization of signaling and adhesive proteins in order to coordinate the formation of a central lumen while maintaining simultaneous adhesion between CBs. Previous studies have shown that the Slit/Roundabout and Netrin/Unc5 repulsive signaling pathways facilitate site-specific loss of adhesion between contralateral CBs in order to form a luminal space. However, the concomitant mechanism by which attraction initiates CB outgrowth and discrete localization of adhesive proteins remains poorly understood. Here we provide genetic evidence that Netrin signals through DCC (Deleted in Colorectal Carcinoma)/UNC-40/Frazzled (Fra) to mediate CB outgrowth and attachment and that this function occurs prior to and independently of Netrin/UNC-5 signaling. fra mRNA is expressed in the CBs prior to and during DV morphogenesis. Loss-of-fra-function results in significant defects in cell shape and alignment between contralateral CB rows. In addition, CB outgrowth and attachment is impaired in both fra loss- and gain-of-function mutants. Deletion of both Netrin genes (NetA and NetB) results in CB attachment phenotypes similar to fra mutants. Similar defects are also seen when both fra and unc5 are deleted. Finally we show that Fra accumulates at dorsal and ventral leading edges of paired CBs, and this localization is dependent upon Netrin. We propose that while repulsive guidance mechanisms contribute to lumen formation by preventing luminal domains from coming together, site-specific Netrin/Frazzled signaling mediates CB attachment. Copyright © 2013 Elsevier Inc. All rights reserved.

Omics Analyses of Trichoderma reesei CBS999.97 and QM6a Indicate the Relevance of Female Fertility to Carbohydrate-Active Enzyme and Transporter Levels

DOE PAGES

Tisch, Doris; Pomraning, Kyle R.; Collett, James R.; ...

2017-09-15

Here, the filamentous fungus Trichoderma reesei is found predominantly in the tropics but also in more temperate regions, such as Europe, and is widely known as a producer of large amounts of plant cell wall-degrading enzymes. We sequenced the genome of the sexually competent isolate CBS999.97, which is phenotypically different from the female sterile strain QM6a but can cross sexually with QM6a. Transcriptome data for growth on cellulose showed that entire carbohydrate-active enzyme (CAZyme) families are consistently differentially regulated between these strains. We evaluated backcrossed strains of both mating types, which acquired female fertility from CBS999.97 but maintained a mostlymore » QM6a genetic background, and we could thereby distinguish between the effects of strain background and female fertility or mating type. We found clear regulatory differences associated with female fertility and female sterility, including regulation of CAZyme and transporter genes. Analysis of carbon source utilization, transcriptomes, and secondary metabolites in these strains revealed that only a few changes in gene regulation are consistently correlated with different mating types. Different strain backgrounds (QM6a versus CBS999.97) resulted in the most significant alterations in the transcriptomes and in carbon source utilization, with decreased growth of CBS999.97 on several amino acids (for example proline or alanine), which further correlated with the downregulation of genes involved in the respective pathways. In combination, our findings support a role of fertility-associated processes in physiology and gene regulation and are of high relevance for the use of sexual crossing in combining the characteristics of two compatible strains or quantitative trait locus (QTL) analysis.« less

Cytologic assessment of estrogen receptor, progesterone receptor, and HER2 status in metastatic breast carcinoma

PubMed Central

Pareja, Fresia; Murray, Melissa P; Jean, Ryan Des; Konno, Fumiko; Friedlander, Maria; Lin, Oscar; Edelweiss, Marcia

2016-01-01

BACKGROUND Discordance in the receptor status between primary breast carcinomas (PBC) and corresponding metastasis is well documented. Interrogation of the receptor status of metastatic breast carcinoma (MBC) in cytology material is common practice; however, its utility has not been thoroughly validated. We studied patients with MBC, and evaluated the concordance rates of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) between PBC surgical specimens and corresponding MBC cell blocks (CBs). We correlated the findings with clinicopathologic variables and with the fixation methods used. METHODS We searched for patients with MBC diagnosed on cytology from 2007 to 2009 and selected those with ER, PR and HER2 tested in both the PBC surgical specimens and the MBC CBs. We included CBs fixed in formalin and methanol based solution (CytoLyt®). All slides were reevaluated by cytopathologists. Clinical information was retrieved from the medical records. RESULTS We studied 65 patients with PBC and MBC paired specimens. The concordance rates between PBC and MBC were 78.5%, 58.5% and 96.9%, for ER, PR and HER2, respectively. When discordant, PR status switched from positive (PBC) to negative (MBC) in most cases (23/27). The PR concordance rate was 45.2% for CBs fixed in formalin and 70.6% for those fixed with CytoLyt® (p=0.047). CONCLUSION The ER, PR and HER2 concordance rates between the PBC and MBC CBs are similar to those reported in paired surgical specimens. PR status was the most prevalent discordance and was not accompanied by a switch in ER. PMID:28529880

Vasopressin V1a receptors are present in the carotid body and contribute to the control of breathing in male Sprague-Dawley rats.

PubMed

Żera, Tymoteusz; Przybylski, Jacek; Grygorowicz, Tomasz; Kasarełło, Kaja; Podobińska, Martyna; Mirowska-Guzel, Dagmara; Cudnoch-Jędrzejewska, Agnieszka

2018-04-01

Vasopressin (AVP) maintains body homeostasis by regulating water balance, cardiovascular system and stress response. AVP inhibits breathing through central vasopressin 1a receptors (V1aRs). Chemoreceptors within carotid bodies (CBs) detect chemical and hormonal signals in the bloodstream and provide sensory input to respiratory and cardiovascular centers of the brainstem. In the study we investigated if CBs contain V1aRs and how the receptors are involved in the regulation of ventilation by AVP. We first immunostained CBs for V1aRs and tyrosine hydroxylase, a marker of chemoreceptor type I (glomus) cells. In urethane-anesthetized adult Sprague-Dawley male rats, we then measured hemodynamic and respiratory responses to systemic (intravenous) or local (carotid artery) administration of AVP prior and after systemic blockade of V1aRs. Immunostaining of CBs showed colocalization of V1aRs and tyrosine hydroxylase within glomus cells. Systemic administration of AVP increased mean arterial blood pressure (MABP) and decreased respiratory rate (RR) and minute ventilation (MV). Local administration of AVP increased MV and RR without significant changes in MABP or heart rate. Pretreatment with V1aR antagonist abolished responses to local and intravenous AVP administration. Our findings show that chemosensory cells within CBs express V1aRs and that local stimulation of the CB with AVP increases ventilation, which is contrary to systemic effects of AVP manifested by decreased ventilation. The responses are mediated by V1aRs, as blockade of the receptors prevents changes in ventilation. We hypothesize that excitatory effects of AVP within the CB provide a counterbalancing mechanism for the inhibitory effects of systemically acting AVP on the respiration. Copyright © 2018 Elsevier Inc. All rights reserved.

Omics Analyses of Trichoderma reesei CBS999.97 and QM6a Indicate the Relevance of Female Fertility to Carbohydrate-Active Enzyme and Transporter Levels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tisch, Doris; Pomraning, Kyle R.; Collett, James R.

Here, the filamentous fungus Trichoderma reesei is found predominantly in the tropics but also in more temperate regions, such as Europe, and is widely known as a producer of large amounts of plant cell wall-degrading enzymes. We sequenced the genome of the sexually competent isolate CBS999.97, which is phenotypically different from the female sterile strain QM6a but can cross sexually with QM6a. Transcriptome data for growth on cellulose showed that entire carbohydrate-active enzyme (CAZyme) families are consistently differentially regulated between these strains. We evaluated backcrossed strains of both mating types, which acquired female fertility from CBS999.97 but maintained a mostlymore » QM6a genetic background, and we could thereby distinguish between the effects of strain background and female fertility or mating type. We found clear regulatory differences associated with female fertility and female sterility, including regulation of CAZyme and transporter genes. Analysis of carbon source utilization, transcriptomes, and secondary metabolites in these strains revealed that only a few changes in gene regulation are consistently correlated with different mating types. Different strain backgrounds (QM6a versus CBS999.97) resulted in the most significant alterations in the transcriptomes and in carbon source utilization, with decreased growth of CBS999.97 on several amino acids (for example proline or alanine), which further correlated with the downregulation of genes involved in the respective pathways. In combination, our findings support a role of fertility-associated processes in physiology and gene regulation and are of high relevance for the use of sexual crossing in combining the characteristics of two compatible strains or quantitative trait locus (QTL) analysis.« less

Molecular genetic analysis in mild hyperhomocysteinemia: A common mutation in the methylenetetrahydrofolate reductase gene is a genetic risk factor for cardiovascular disease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kluijtmans, L.A.J.; Heuvel, L.P.W.J. van den; Stevens, E.M.B.

1996-01-01

Mild hyperhomocysteinemia is an established risk factor for cardiovascular disease. Genetic aberrations in the cystathionine P-synthase (CBS) and methylenetetrahydrofolate reductase (MTHFR) genes may account for reduced enzyme activities and elevated plasma homocysteine levels. In 15 unrelated Dutch patients with homozygous CBS deficiency, we observed the 833T{yields}C (1278T) mutation in 50% of the alleles. Very recently, we identified a common mutation (677C{yields}T; A{yields}V) in the MTHFR gene, which, in homozygous state, is responsible for the thermolabile phenotype and which is associated with decreased specific MTHFR activity and elevated homocysteine levels. We screened 60 cardiovascular patients and 111 controls for these twomore » mutations, to determine whether these mutations are risk factors for premature cardiovascular disease. Heterozygosity for the 833T{yields}C mutation in the CBS gene was observed in one individual of the control group but was absent in patients with premature cardiovascular disease. Homozygosity for the 677C-{yields}T mutation in the MTHFR gene was found in 9 (15%) of 60 cardiovascular patients and in only 6 ({approximately}5%) of 111 control individuals (odds ratio 3.1 [95% confidence interval 1.0-9.21]). Because of both the high prevalence of the 833T-{yields}C mutation among homozygotes for CBS deficiency and its absence in 60 cardiovascular patients, we may conclude that heterozygosity for CBS deficiency does not appear to be involved in premature cardiovascular disease. However, a frequent homozygous mutation in the MTHFR gene is associated with a threefold increase in risk for premature cardiovascular disease. 35 refs., 3 figs., 1 tab.« less

Phytocannabinoids for Cancer Therapeutics: Recent Updates and Future Prospects.

PubMed

Patil, K R; Goyal, S N; Sharma, C; Patil, C R; Ojha, S

2015-01-01

Phytocannabinoids (pCBs) are lipid-soluble phytochemicals present in the plant, Cannabis sativa L. and non-cannabis plants which have a long history in recreation and traditional medicine. The plant and the constituents isolated were central in the discovery of the endocannabinoid system (ECS), the most new target for drug discovery. The ECS includes two G-protein-coupled receptors; the cannabinoid receptors-1 and -2 (CB1 and CB2) for marijuana's psychoactive principle Δ(9)-tetrahydrocannabinol (Δ(9)-THC), their endogenous small lipid ligands; namely anandamide (AEA) and 2-arachidonoylglycerol (2-AG), also known as endocannabinoids and the enzymes for endocannabinoid biosynthesis and degradation such as fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL). The ECS has been suggested as a pro-homeostatic and pleiotropic signaling system activated in a time- and tissue-specific way during pathological conditions including cancer. Targeting the CB1 receptors becomes a concern because of adverse psychotropic reactions. Hence, targeting the CB2 receptors or the endocannabinoid metabolizing enzymes by pCBs obtained from plants lacking psychotropic adverse reactions has garnered interest in drug discovery. These pCBs derived from plants appear safe and effective with a wider access and availability. In the recent years, several pCBs derived other than non-cannabinoid plants have been reported to bind to and functionally interact with cannabinoid receptors and appear promising candidate for drug development including cancer therapeutics. Several of them also targets the endocannabinoid metabolizing enzymes that control endocannabinoid levels. In this article, we summarize and critically discuss the updates and future prospects of the pCBs as novel and promising candidates for cancer therapeutics.

Accurate prediction of bond dissociation energies of large n-alkanes using ONIOM-CCSD(T)/CBS methods

NASA Astrophysics Data System (ADS)

Wu, Junjun; Ning, Hongbo; Ma, Liuhao; Ren, Wei

2018-05-01

Accurate determination of the bond dissociation energies (BDEs) of large alkanes is desirable but practically impossible due to the expensive cost of high-level ab initio methods. We developed a two-layer ONIOM-CCSD(T)/CBS method which treats the high layer with CCSD(T) method and the low layer with DFT method, respectively. The accuracy of this method was validated by comparing the calculated BDEs of n-hexane with that obtained at the CCSD(T)-F12b/aug-cc-pVTZ level of theory. On this basis, the C-C BDEs of C6-C20 n-alkanes were calculated systematically using the ONIOM [CCSD(T)/CBS(D-T):M06-2x/6-311++G(d,p)] method, showing a good agreement with the data available in the literature.

Intercell scheduling: A negotiation approach using multi-agent coalitions

NASA Astrophysics Data System (ADS)

Tian, Yunna; Li, Dongni; Zheng, Dan; Jia, Yunde

2016-10-01

Intercell scheduling problems arise as a result of intercell transfers in cellular manufacturing systems. Flexible intercell routes are considered in this article, and a coalition-based scheduling (CBS) approach using distributed multi-agent negotiation is developed. Taking advantage of the extended vision of the coalition agents, the global optimization is improved and the communication cost is reduced. The objective of the addressed problem is to minimize mean tardiness. Computational results show that, compared with the widely used combinatorial rules, CBS provides better performance not only in minimizing the objective, i.e. mean tardiness, but also in minimizing auxiliary measures such as maximum completion time, mean flow time and the ratio of tardy parts. Moreover, CBS is better than the existing intercell scheduling approach for the same problem with respect to the solution quality and computational costs.

Ab initio calculations, structure, NBO and NCI analyses of Xsbnd H⋯π interactions

NASA Astrophysics Data System (ADS)

Wu, Qiyang; Su, He; Wang, Hongyan; Wang, Hui

2018-02-01

The performance of ab initio methods (MP2, DFT/B3LYP, random-phase approximation (RPA), CCSD(T) and QCISD(T)) in predicting interaction energy of Xsbnd H⋯π (Xsbnd H = HCCH, HCl, HF; π = C2H2, C2H4, C6H6) hydrogen complexes are assessed systematically. The CCSD(T)/CBS benchmarks of interaction energy are reported. It is found that RPA agrees well with CCSD(T)/CBS benchmarks and experimental results. CCSD(T) and QCISD(T) perform the best only when compared with CCSD(T)/CBS benchmarks, MP2 performs well only for experimental data. B3LYP provides the worst accuracy. Additionally, the equilibrium structure, interaction type of Xsbnd H⋯π hydrogen complexes are investigated by the natural bond orbital (NBO) and the non-covalent interaction index (NCI).

Compensatory Beliefs about Glucose Testing are Associated with Low Adherence to Treatment and Poor Metabolic Control in Adolescents with Type 1 Diabetes

ERIC Educational Resources Information Center

Rabiau, Marjorie A.; Knauper, Barbel; Nguyen, Thien-Kim; Sufrategui, Maria; Polychronakos, Constantin

2009-01-01

The goal of this research was to investigate whether compensatory beliefs (CBs) regarding glucose testing predict blood glucose levels and adherence to treatment in adolescents with type 1 diabetes. CBs are convictions that the negative effects of one behavior (e.g. not testing one's glucose level) can be compensated for by engaging in another…

Candida dajiaensis sp. nov., Candida yuanshanicus sp. nov., Candida jianshihensis sp. nov., and Candida sanyiensis sp. nov., four anamorphic, ascomycetous yeast species isolated from soil in Taiwan.

PubMed

Liu, Chun-Hao; Young, Shuh-Sen; Chang, Tsung-Chain; Lee, Ching-Fu

2008-08-01

Nine anamorphic, ascomycetous yeast strains belonging to the Pichia anomala clade were recovered from forest soil in 2006 in Taiwan. The nine yeast strains represent four novel yeast species based on the sequences of their D1/D2 domain of the large subunit (LSU) rRNA gene and their physiological characteristics. The scientific names of Candida dajiaensis sp. nov., Candida yuanshanicus sp. nov., Candida jianshihensis sp. nov., and Candida sanyiensis sp. nov. are proposed for these novel yeast species. The type strains are C. dajiaensis SM11S03(T) (=CBS 10590(T)=BCRC 23099(T)), C. yuanshanicus SY3S02(T) (=CBS 10589(T)=BCRC 23100(T)), C. jianshihensis SM8S04(T) (=CBS 10591(T)=BCRC 23096(T)), and C. sanyiensis SA1S06(T) (=CBS 10592(T)=BCRC 23094(T)). Sequence analysis of the D1/D2 of the LSU rRNA gene revealed that the three species, C. dajiaensis, C. yuanshanicus and Pichia onychis, shared a separate branch in the phylogenetic tree, C. jianshihensis is phylogenetically related to Candida ulmi and Pichia alni, and the phylogenetically closest relative of C. sanyiensis is Pichia populi.

Trial-based psychotherapy and the efficacy of trial-based thought record in changing unhelpful core beliefs and reducing self-criticism.

PubMed

de Oliveira, Irismar Reis; Hemmany, Curt; Powell, Vania B; Bonfim, Thaís D; Duran, Erica P; Novais, Nilma; Velasquez, Michella; Di Sarno, Elaine; Alves, Gledson L; Cesnik, Joici A

2012-03-01

The best prevention against relapse results when patients are taught to restructure negative core beliefs (CBs). Efficacy of the trial-based thought record (TBTR) in decreasing the credit given by patients to negative CBs and corresponding emotions was evaluated. Patients (n = 166) were submitted to a simulation of a legal trial to assess their adherence to negative CBs and corresponding emotions after each cognitive therapy technique incorporated by TBTR. Significant reductions existed in percent values after the first and second defense attorney pleas, as well as after jury's verdict and initial preparation for the appeal (p < 0.001), relative to the investigation phase. Significant differences also emerged between the defense attorney's first and second pleas and between the defense attorney's second plea and jury's verdict, as well as preparation for the appeal (p < 0.001). There was no significant difference between percentages presented by patients submitted to TBTR used in the empty chair format relative to the conventional format. Similarly, there was no difference between outcomes, regardless of therapists' level of exposure to TBTR. TBTR may help patients reduce attachment to negative CBs and corresponding emotions. Outcomes were significantly favorable regardless of the format use and therapists' level of exposure to TBTR.

Experiences of Rehabilitation Professionals with the Implementation of a Back School for Patients with Chronic Low Back Pain: A Qualitative Study.

PubMed

Peters, Stefan; Faller, Hermann; Pfeifer, Klaus; Meng, Karin

2016-01-01

A standardized curriculum back school (CBS) has been recommended for further dissemination in medical rehabilitation in Germany. However, implementation of self-management education programs into practice is challenging. In low back pain care, individual factors of professionals could be decisive regarding implementation fidelity. The study aim was to explore attitudes and experiences of professionals who conducted the back school. Qualitative interviews were led with 45 rehabilitation professionals. The data were examined using thematic analysis. Three central themes were identified: (a) "back school as a common thread," (b) "theory versus practice," and (c) "participation and patient-centeredness." The CBS and its manual were frequently described positively because they provide structure. However, specified time was mentioned critically and there were heterogeneous perceptions regarding flexibility in conducting the CBS. Theory and practice in the CBS were discussed concerning amount, distribution, and conjunction. Participation and patient-centeredness were mainly mentioned in terms of amount and heterogeneity of participation as well as the demand for competences of professionals. Factors were detected that may either positively or negatively influence the implementation fidelity of self-management education programs. The results are explorative and provide potential explanatory mechanisms for behavior and acceptance of rehabilitation professionals regarding the implementation of biopsychosocial back schools.

Geometric Energy Derivatives at the Complete Basis Set Limit: Application to the Equilibrium Structure and Molecular Force Field of Formaldehyde.

PubMed

Morgan, W James; Matthews, Devin A; Ringholm, Magnus; Agarwal, Jay; Gong, Justin Z; Ruud, Kenneth; Allen, Wesley D; Stanton, John F; Schaefer, Henry F

2018-03-13

Geometric energy derivatives which rely on core-corrected focal-point energies extrapolated to the complete basis set (CBS) limit of coupled cluster theory with iterative and noniterative quadruple excitations, CCSDTQ and CCSDT(Q), are used as elements of molecular gradients and, in the case of CCSDT(Q), expansion coefficients of an anharmonic force field. These gradients are used to determine the CCSDTQ/CBS and CCSDT(Q)/CBS equilibrium structure of the S 0 ground state of H 2 CO where excellent agreement is observed with previous work and experimentally derived results. A fourth-order expansion about this CCSDT(Q)/CBS reference geometry using the same level of theory produces an exceptional level of agreement to spectroscopically observed vibrational band origins with a MAE of 0.57 cm -1 . Second-order vibrational perturbation theory (VPT2) and variational discrete variable representation (DVR) results are contrasted and discussed. Vibration-rotation, anharmonicity, and centrifugal distortion constants from the VPT2 analysis are reported and compared to previous work. Additionally, an initial application of a sum-over-states fourth-order vibrational perturbation theory (VPT4) formalism is employed herein, utilizing quintic and sextic derivatives obtained with a recursive algorithmic approach for response theory.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miliordos, Evangelos; Aprà, Edoardo; Xantheas, Sotiris S.

We establish a new estimate for the binding energy between two benzene molecules in the parallel-displaced (PD) conformation by systematically converging (i) the intra- and intermolecular geometry at the minimum, (ii) the expansion of the orbital basis set, and (iii) the level of electron correlation. The calculations were performed at the second-order Møller–Plesset perturbation (MP2) and the coupled cluster including singles, doubles, and a perturbative estimate of triples replacement [CCSD(T)] levels of electronic structure theory. At both levels of theory, by including results corrected for basis set superposition error (BSSE), we have estimated the complete basis set (CBS) limit bymore » employing the family of Dunning’s correlation-consistent polarized valence basis sets. The largest MP2 calculation was performed with the cc-pV6Z basis set (2772 basis functions), whereas the largest CCSD(T) calculation was with the cc-pV5Z basis set (1752 basis functions). The cluster geometries were optimized with basis sets up to quadruple-ζ quality, observing that both its intra- and intermolecular parts have practically converged with the triple-ζ quality sets. The use of converged geometries was found to play an important role for obtaining accurate estimates for the CBS limits. Our results demonstrate that the binding energies with the families of the plain (cc-pVnZ) and augmented (aug-cc-pVnZ) sets converge [within <0.01 kcal/mol for MP2 and <0.15 kcal/mol for CCSD(T)] to the same CBS limit. In addition, the average of the uncorrected and BSSE-corrected binding energies was found to converge to the same CBS limit much faster than either of the two constituents (uncorrected or BSSE-corrected binding energies). Due to the fact that the family of augmented basis sets (especially for the larger sets) causes serious linear dependency problems, the plain basis sets (for which no linear dependencies were found) are deemed as a more efficient and straightforward path for obtaining an accurate CBS limit. We considered extrapolations of the uncorrected (ΔE) and BSSE-corrected (ΔE cp) binding energies, their average value (ΔE ave), as well as the average of the latter over the plain and augmented sets (Δ~E ave) with the cardinal number of the basis set n. Our best estimate of the CCSD(T)/CBS limit for the π–π binding energy in the PD benzene dimer is D e = -2.65 ± 0.02 kcal/mol. The best CCSD(T)/cc-pV5Z calculated value is -2.62 kcal/mol, just 0.03 kcal/mol away from the CBS limit. For comparison, the MP2/CBS limit estimate is -5.00 ± 0.01 kcal/mol, demonstrating a 90% overbinding with respect to CCSD(T). Finally, the spin-component-scaled (SCS) MP2 variant was found to closely reproduce the CCSD(T) results for each basis set, while scaled opposite spin (SOS) MP2 yielded results that are too low when compared to CCSD(T).« less

User's manual for CBS3DS, version 1.0

NASA Astrophysics Data System (ADS)

Reddy, C. J.; Deshpande, M. D.

1995-10-01

CBS3DS is a computer code written in FORTRAN 77 to compute the backscattering radar cross section of cavity backed apertures in infinite ground plane and slots in thick infinite ground plane. CBS3DS implements the hybrid Finite Element Method (FEM) and Method of Moments (MoM) techniques. This code uses the tetrahedral elements, with vector edge basis functions for FEM in the volume of the cavity/slot and the triangular elements with the basis functions for MoM at the apertures. By virtue of FEM, this code can handle any arbitrarily shaped three-dimensional cavities filled with inhomogeneous lossy materials; due to MoM, the apertures can be of any arbitrary shape. The User's Manual is written to make the user acquainted with the operation of the code. The user is assumed to be familiar with the FORTRAN 77 language and the operating environment of the computer the code is intended to run.

Momentum signatures of the Anderson transition

NASA Astrophysics Data System (ADS)

Sanjib, Ghosh

This thesis explores for possible signatures of Anderson localization and the Anderson metal-insulator transition (MIT) in momentum space. We find that an initial plane-wave propagating in a disordered medium exhibits a diffusive background and two interference peaks, the coherent backscattering (CBS) and the coherent forward scattering (CFS) peaks in the momentum distribution. We show, the signatures of Anderson localization and the Anderson transition are encoded in the dynamical properties of the two interference peaks, CBS and CFS. We develop finite-time scaling theory for the angular width of the CBS peak and in the height of the CFS peak. We demonstrate how to extract properties like critical exponent, the mobility edge and signatures of multifractality from this finite-time analysis. These momentum space signatures of the Anderson transition are novel and they promise to be experimental observables for wide range of systems, from cold atoms to classical waves or any wave systems where the momentum distribution is accessible.

Schematic for efficient computation of GC, GC3, and AT3 bias spectra of genome

PubMed Central

Rizvi, Ahsan Z; Venu Gopal, T; Bhattacharya, C

2012-01-01

Selection of synonymous codons for an amino acid is biased in protein translation process. This biased selection causes repetition of synonymous codons in structural parts of genome that stands for high N/3 peaks in DNA spectrum. Period-3 spectral property is utilized here to produce a 3-phase network model based on polyphase filterbank concepts for derivation of codon bias spectra (CBS). Modification of parameters in this model can produce GC, GC3, and AT3 bias spectra. Complete schematic in LabVIEW platform is presented here for efficient and parallel computation of GC, GC3, and AT3 bias spectra of genomes alongwith results of CBS patterns. We have performed the correlation coefficient analysis of GC, GC3, and AT3 bias spectra with codon bias patterns of CBS for biological and statistical significance of this model. PMID:22368390

Schematic for efficient computation of GC, GC3, and AT3 bias spectra of genome.

PubMed

Rizvi, Ahsan Z; Venu Gopal, T; Bhattacharya, C

2012-01-01

Selection of synonymous codons for an amino acid is biased in protein translation process. This biased selection causes repetition of synonymous codons in structural parts of genome that stands for high N/3 peaks in DNA spectrum. Period-3 spectral property is utilized here to produce a 3-phase network model based on polyphase filterbank concepts for derivation of codon bias spectra (CBS). Modification of parameters in this model can produce GC, GC3, and AT3 bias spectra. Complete schematic in LabVIEW platform is presented here for efficient and parallel computation of GC, GC3, and AT3 bias spectra of genomes alongwith results of CBS patterns. We have performed the correlation coefficient analysis of GC, GC3, and AT3 bias spectra with codon bias patterns of CBS for biological and statistical significance of this model.

Batch-Versuche zur Bestimmung der Sorption und Reaktionskinetik von fluoreszierenden Tracern

NASA Astrophysics Data System (ADS)

Vaitl, Tobias; Wohnlich, Stefan

2018-06-01

For many tracer experiments, prior determination of interaction between solid medium and used tracers is of major interest in order to achieve efficient, economic and successful field experiments. In the present study, three different types of batch experiments were performed with three fluorescent dyes (Na-Fluorescein, Amidorhodamin G and Tinopal CBS-X) and three different rock types (sandstone, claystone and limestone), to determine distribution coefficients and reaction kinetics. All three rock types were analysed for organic carbon content, specific surface area and mineralogical composition to identify the main sorption mechanisms. For all tracers, different sorption properties were found depending on the type of rock. The strongest sorption was observed for Tinopal CBS-X in contact with claystone. Only Na-Fluorescein showed sorption (albeit limited) in contact with the sandstones. The investigated limestones indicated a high sorption for the tracer Tinopal CBS-X. Regarding reaction kinetics, in most cases, thermodynamic equilibrium conditions were reached after two weeks.

Direct weak localization signature with ultracold atoms: the CBS revival

NASA Astrophysics Data System (ADS)

Josse, Vincent

2016-05-01

Ultracold atomic systems in presence of disorder have attracted a lot of interest over the past decade, in particular to study the physics of Anderson localization (AL) in a renewed perspective. Landmark experiments have been demonstrated, in 1D and 3D geometries. However many challenges remain and new ideas have emerged, as for instance the search for original signatures of Anderson localization in momentum space. Here I will describe our progresses along that line where a weak localization effect has been directly observed, i.e. the Coherent Backscattering (CBS) phenomenon. In particular I will report on the recent observation of suppression and revival of CBS when a controlled dephasing kick is applied to the system. This observation demonstrates a novel and general method, introduced by T. Micklitz and coworkers, to study probe phase coherence in disordered systems by manipulating time reversal symmetry.

Variability in the Milky Way: Contact Binaries as Diagnostic Tools

NASA Astrophysics Data System (ADS)

de Grijs, R.; Chen, X.; Deng, L.

2017-07-01

We used the 50 cm Binocular Network (50BiN) telescope at Delingha Station (Qinghai Province) of Purple Mountain Observatory (Chinese Academy of Sciences) to obtain simultaneous V- and R-band observations of the old open cluster NGC 188. Our aim was a search for populations of variable stars. We derived light-curve solutions for six W Ursae Majoris (W UMa) eclipsing-binary systems and estimated their orbital parameters. The resulting distance to the W UMas is independent of the physical characteristics of the host cluster. We next determined the current best period-luminosity relations for contact binaries (CBs; scatter σ<0.10 mag). We conclude that CBs can be used as distance tracers with better than 5% uncertainty. We apply our new relations to the 102 CBs in the Large Magellanic Cloud, which yields a distance modulus of (m-M)V,0=18.41±0.20 mag.

Reconstruction and visualization of carbohydrate, N-glycosylation pathways in Pichia pastoris CBS7435 using computational and system biology approaches.

PubMed

Srivastava, Akriti; Somvanshi, Pallavi; Mishra, Bhartendu Nath

2013-06-01

Pichia pastoris is an efficient expression system for production of recombinant proteins. To understand its physiology for building novel applications it is important to understand and reconstruct its metabolic network. The metabolic reconstruction approach connects genotype with phenotype. Here, we have attempted to reconstruct carbohydrate metabolism pathways responsible for high biomass density and N-glycosylation pathways involved in the post translational modification of proteins of P. pastoris CBS7435. Both these metabolic pathways play a crucial role in heterologous protein production. We report novel, missing and unannotated enzymes involved in the target metabolic pathways. A strong possibility of cellulose and xylose metabolic processes in P. pastoris CBS7435 suggests its use in the area of biofuels. The reconstructed metabolic networks can be used for increased yields and improved product quality, for designing appropriate growth medium, for production of recombinant therapeutics and for making biofuels.

Compulsive buying and borderline personality symptomatology.

PubMed

Sansone, Randy A; Chang, Joy; Jewell, Bryan; Sellbom, Martin; Bidwell, Mark

2013-04-01

In this study, the authors investigated the relationship between compulsive buying and borderline personality disorder (BPD) symptomatology--two disorders possibly linked through impulsivity. Using a survey methodology in a cross-sectional consecutive sample of nonemergent female outpatients from an obstetrics/gynecology clinic, the authors assessed compulsive buying with the compulsive buying scale (CBS) and BPD symptomatology through the BPD scale of the personality diagnostic questionnaire-4 (PDQ-4) and the self-harm Inventory (SHI). In this sample, 8% of Caucasian women and 9% of African-American women scored positively for compulsive buying. The correlations between scores on the CBS and the PDQ-4 and SHI were 0.43 and 0.41, respectively-both statistically significant at the p < .001 level. Compared to Caucasian women, African-American women demonstrated statistical associations between the BPD measures and the CBS scale scores that were significantly larger. Findings suggest relationships between compulsive buying and BPD, particularly among African-American women.

Childhood trauma and compulsive buying.

PubMed

Sansone, Randy A; Chang, Joy; Jewell, Bryan; Rock, Rachel

2013-02-01

Childhood trauma has been empirically associated with various types of self-regulatory difficulties in adulthood. However, according to the extant literature, no study has examined relationships between various types of childhood trauma and compulsive buying behavior in adulthood. Using a self-report survey methodology in a cross-sectional consecutive sample of 370 obstetrics/gynecology patients, we examined five types of childhood trauma before the age of 12 years (i.e. witnessing violence, physical neglect, emotional abuse, physical abuse, sexual abuse) in relationship to compulsive buying as assessed by the Compulsive Buying Scale (CBS). All forms of trauma demonstrated statistically significant correlations with the CBS. Using a linear regression analysis, both witnessing violence and emotional abuse significantly contributed to CBS scores. Further analyses indicated that race did not moderate the relationship between childhood trauma and compulsive buying. Findings indicate that various forms of childhood trauma are correlated with compulsive buying behavior, particularly witnessing violence and emotional abuse.

Crystallinity properties and crystallization behavior of chocolate fat blends.

PubMed

da Silva, Thais Lomonaco Teodoro; Grimaldi, Renato; Calligaris, Guilherme Andrade; Cardoso, Lisandro Pavie; Gonçalves, Lireny Aparecida Guaraldo

2017-06-01

Cocoa butter (CB) provides unique crystallization characteristics to chocolates and confectionary products; hence, it is an important value-add product. However, other alternative fats that minimally affect the crystallization behaviour of chocolates and confectionary products are now being increasingly used. This study analyzed the crystallization behaviour of CB, cocoa butter substitutes (CBSs), and their blends. Blends were prepared using CBS concentrations: 5, 10, 15, 20 and 37.5%. CB, CBS, and their blends were evaluated by following analysis: solid fat content, isothermal analysis, polarized light microscopic, thermal behaviour, X-ray diffraction and consistency. Crystallization analysis showed an incompatibility between the 2 fats, with a reduction in the crystallinity and increase in liquid content in all the blends. Eutectic crystallization at 20 °C was only observed for the blend containing 20% CBSs. This was considered as a positive result because previous studies have indicated that CBS concentration in CB blends should not be more than 5%.

Candida asparagi sp. nov., Candida diospyri sp. nov. and Candida qinlingensis sp. nov., novel anamorphic, ascomycetous yeast species.

PubMed

Lu, Hui-Zhong; Jia, Jian-Hua; Wang, Qi-Ming; Bai, Feng-Yan

2004-07-01

Among ascomycetous yeasts that were isolated from several nature reserve areas in China, three anamorphic strains isolated from soil (QL 5-5T) and fruit (QL 21-2T and SN 15-1T) were revealed, by conventional characterization and molecular phylogenetic analysis based on internal transcribed spacer and large subunit (26S) rRNA gene D1/D2 region sequencing, to represent three novel species in the genus Candida. Candida qinlingensis sp. nov. (type strain, QL 5-5T=AS 2.2524T=CBS 9768T) was related closely to a teleomorphic species, Williopsis pratensis. The close relatives of Candida diospyri sp. nov. (type strain, QL 21-2T=AS 2.2525T=CBS 9769T) are Candida friedrichii and Candida membranifaciens. Candida asparagi sp. nov. (type strain, SN 15-1T=AS 2.2526T=CBS 9770T) forms a clade with Candida fructus.

Omics Analyses of Trichoderma reesei CBS999.97 and QM6a Indicate the Relevance of Female Fertility to Carbohydrate-Active Enzyme and Transporter Levels.

PubMed

Tisch, Doris; Pomraning, Kyle R; Collett, James R; Freitag, Michael; Baker, Scott E; Chen, Chia-Ling; Hsu, Paul Wei-Che; Chuang, Yu Chien; Schuster, Andre; Dattenböck, Christoph; Stappler, Eva; Sulyok, Michael; Böhmdorfer, Stefan; Oberlerchner, Josua; Wang, Ting-Fang; Schmoll, Monika

2017-11-15

The filamentous fungus Trichoderma reesei is found predominantly in the tropics but also in more temperate regions, such as Europe, and is widely known as a producer of large amounts of plant cell wall-degrading enzymes. We sequenced the genome of the sexually competent isolate CBS999.97, which is phenotypically different from the female sterile strain QM6a but can cross sexually with QM6a. Transcriptome data for growth on cellulose showed that entire carbohydrate-active enzyme (CAZyme) families are consistently differentially regulated between these strains. We evaluated backcrossed strains of both mating types, which acquired female fertility from CBS999.97 but maintained a mostly QM6a genetic background, and we could thereby distinguish between the effects of strain background and female fertility or mating type. We found clear regulatory differences associated with female fertility and female sterility, including regulation of CAZyme and transporter genes. Analysis of carbon source utilization, transcriptomes, and secondary metabolites in these strains revealed that only a few changes in gene regulation are consistently correlated with different mating types. Different strain backgrounds (QM6a versus CBS999.97) resulted in the most significant alterations in the transcriptomes and in carbon source utilization, with decreased growth of CBS999.97 on several amino acids (for example proline or alanine), which further correlated with the downregulation of genes involved in the respective pathways. In combination, our findings support a role of fertility-associated processes in physiology and gene regulation and are of high relevance for the use of sexual crossing in combining the characteristics of two compatible strains or quantitative trait locus (QTL) analysis. IMPORTANCE Trichoderma reesei is a filamentous fungus with a high potential for secretion of plant cell wall-degrading enzymes. We sequenced the genome of the fully fertile field isolate CBS999.97 and analyzed its gene regulation characteristics in comparison with the commonly used laboratory wild-type strain QM6a, which is not female fertile. Additionally, we also evaluated fully fertile strains with genotypes very close to that of QM6a in order to distinguish between strain-specific and fertility-specific characteristics. We found that QM6a and CBS999.97 clearly differ in their growth patterns on different carbon sources, CAZyme gene regulation, and secondary metabolism. Importantly, we found altered regulation of 90 genes associated with female fertility, including CAZyme genes and transporter genes, but only minor mating type-dependent differences. Hence, when using sexual crossing in research and for strain improvement, it is important to consider female fertile and female sterile strains for comparison with QM6a and to achieve optimal performance. Copyright © 2017 Tisch et al.

Detection of Prostate Cancer: Quantitative Multiparametric MR Imaging Models Developed Using Registered Correlative Histopathology.

PubMed

Metzger, Gregory J; Kalavagunta, Chaitanya; Spilseth, Benjamin; Bolan, Patrick J; Li, Xiufeng; Hutter, Diane; Nam, Jung W; Johnson, Andrew D; Henriksen, Jonathan C; Moench, Laura; Konety, Badrinath; Warlick, Christopher A; Schmechel, Stephen C; Koopmeiners, Joseph S

2016-06-01

Purpose To develop multiparametric magnetic resonance (MR) imaging models to generate a quantitative, user-independent, voxel-wise composite biomarker score (CBS) for detection of prostate cancer by using coregistered correlative histopathologic results, and to compare performance of CBS-based detection with that of single quantitative MR imaging parameters. Materials and Methods Institutional review board approval and informed consent were obtained. Patients with a diagnosis of prostate cancer underwent multiparametric MR imaging before surgery for treatment. All MR imaging voxels in the prostate were classified as cancer or noncancer on the basis of coregistered histopathologic data. Predictive models were developed by using more than one quantitative MR imaging parameter to generate CBS maps. Model development and evaluation of quantitative MR imaging parameters and CBS were performed separately for the peripheral zone and the whole gland. Model accuracy was evaluated by using the area under the receiver operating characteristic curve (AUC), and confidence intervals were calculated with the bootstrap procedure. The improvement in classification accuracy was evaluated by comparing the AUC for the multiparametric model and the single best-performing quantitative MR imaging parameter at the individual level and in aggregate. Results Quantitative T2, apparent diffusion coefficient (ADC), volume transfer constant (K(trans)), reflux rate constant (kep), and area under the gadolinium concentration curve at 90 seconds (AUGC90) were significantly different between cancer and noncancer voxels (P < .001), with ADC showing the best accuracy (peripheral zone AUC, 0.82; whole gland AUC, 0.74). Four-parameter models demonstrated the best performance in both the peripheral zone (AUC, 0.85; P = .010 vs ADC alone) and whole gland (AUC, 0.77; P = .043 vs ADC alone). Individual-level analysis showed statistically significant improvement in AUC in 82% (23 of 28) and 71% (24 of 34) of patients with peripheral-zone and whole-gland models, respectively, compared with ADC alone. Model-based CBS maps for cancer detection showed improved visualization of cancer location and extent. Conclusion Quantitative multiparametric MR imaging models developed by using coregistered correlative histopathologic data yielded a voxel-wise CBS that outperformed single quantitative MR imaging parameters for detection of prostate cancer, especially when the models were assessed at the individual level. (©) RSNA, 2016 Online supplemental material is available for this article.

Improving cyanobacterail O 2-tolerance using CBS hydrogenase for hydrogen production

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maness, Pin-Ching; Eckert, Carrie; Wawrousek, Karen

2016-11-11

Cyanobacterial H 2 production is a viable path to renewable H 2 with water serving as the electron donor and sunlight the energy source. A grand challenge is the sensitivity of the underlying hydrogenase to O 2, the latter an inherent byproduct of oxygenic photosynthesis. This challenge has been identified as a technical barrier in the Fuel Cell Technologies Office (FCTO) Multi-year Research, Development and Deployment Plan. One solution is to express in cyanobacterium an O 2-tolerant hydrogenase to circumvent this barrier. We have uncovered an O 2-tolerant hydrogenase from a photosynthetic bacterium Rubrivivax gelatinosus CBS (Casa Bonita Strain; hereaftermore » “CBS”) with a half-life near 21 h when exposed to ambient O 2. We sequenced the CBS genome and identified two sets of maturation machineries hyp1 and hyp2. Transcripts expression analysis and mutagenesis revealed that hyp1 is responsible for the assembly of the O 2-tolerant CO-oxidation (Coo) hydrogenase and hyp2 is involved in the maturation of a H 2-uptake hydrogenase. The structural genes encoding the O 2-tolerant hydrogenase (cooLXUH) and maturation genes hyp1FABCDE were therefore cloned and expressed in the model cyanobacterium Synechocystis sp. PCC 6803. We obtained several recombinants displaying hydrogenase activity in a Synechocystis host lacking background activity, suggesting that the CBS hydrogenase is active in Synechocystis. Yet the activity is extremely low. To ensure balanced protein expression, we systematically optimized heterologous expression of 10 CBS genes by using stronger promoters and better ribosome binding site. Moreover we attempted the expression of cooM and cooK genes, verified to be important in CBS to afford activity. CooM is a very large protein and both CooM and CooK are membrane-associated. These properties limited our success in expressing both genes in Synechocystis, although they were both expressed in E. coli yet with no activity. This project was terminated in FY2016 due to the inability to generate a Synechocystis strain with consistent and active H 2 production activity. Nevertheless the research has led to a few high-impact publications and numerous conference presentations to increase global visibility of the DOE-funded research.« less

Military Personnel Dilemmas: Perspectives on Gender-Related Issues. A Selected List of Resource Materials.

DTIC Science & Technology

1981-05-01

34Army Discharges Wornan After MIarriaqe To Alleged Transsexual ." CBS NEWS. July 21, 1977. p.11. (Morning News). "Army Seeks Dismissal Of Woman...Married To Transsexual ." CBS NEWS. June 6, 1977. p.19. (Morninq News) Austen, Roger. "gut For Fate And Can: Homosexual Villains And Victims In The...identity and sexual behavior are markedly aberrant; homosexuality, transsexualism , and transvestism. For each disorder a psychodynamic analysis of the

Oilbirds produce echolocation signals beyond their best hearing range and adjust signal design to natural light conditions

PubMed Central

Brinkløv, Signe; Elemans, Coen P. H.

2017-01-01

Oilbirds are active at night, foraging for fruits using keen olfaction and extremely light-sensitive eyes, and echolocate as they leave and return to their cavernous roosts. We recorded the echolocation behaviour of wild oilbirds using a multi-microphone array as they entered and exited their roosts under different natural light conditions. During echolocation, the birds produced click bursts (CBs) lasting less than 10 ms and consisting of a variable number (2–8) of clicks at 2–3 ms intervals. The CBs have a bandwidth of 7–23 kHz at −6 dB from signal peak frequency. We report on two unique characteristics of this avian echolocation system. First, oilbirds reduce both the energy and number of clicks in their CBs under conditions of clear, moonlit skies, compared with dark, moonless nights. Second, we document a frequency mismatch between the reported best frequency of oilbird hearing (approx. 2 kHz) and the bandwidth of their echolocation CBs. This unusual signal-to-sensory system mismatch probably reflects avian constraints on high-frequency hearing but may still allow oilbirds fine-scale, close-range detail resolution at the upper extreme (approx. 10 kHz) of their presumed hearing range. Alternatively, oilbirds, by an as-yet unknown mechanism, are able to hear frequencies higher than currently appreciated. PMID:28573036

Compact tunable Compton x-ray source from laser-plasma accelerator and plasma mirror

NASA Astrophysics Data System (ADS)

Tsai, Hai-En; Wang, Xiaoming; Shaw, Joseph M.; Li, Zhengyan; Arefiev, Alexey V.; Zhang, Xi; Zgadzaj, Rafal; Henderson, Watson; Khudik, V.; Shvets, G.; Downer, M. C.

2015-02-01

We present an in-depth experimental-computational study of the parameters necessary to optimize a tunable, quasi-monoenergetic, efficient, low-background Compton backscattering (CBS) x-ray source that is based on the self-aligned combination of a laser-plasma accelerator (LPA) and a plasma mirror (PM). The main findings are (1) an LPA driven in the blowout regime by 30 TW, 30 fs laser pulses produce not only a high-quality, tunable, quasi-monoenergetic electron beam, but also a high-quality, relativistically intense (a0 ˜ 1) spent drive pulse that remains stable in profile and intensity over the LPA tuning range. (2) A thin plastic film near the gas jet exit retro-reflects the spent drive pulse efficiently into oncoming electrons to produce CBS x-rays without detectable bremsstrahlung background. Meanwhile, anomalous far-field divergence of the retro-reflected light demonstrates relativistic "denting" of the PM. Exploiting these optimized LPA and PM conditions, we demonstrate quasi-monoenergetic (50% FWHM energy spread), tunable (75-200 KeV) CBS x-rays, characteristics previously achieved only on more powerful laser systems by CBS of a split-off, counter-propagating pulse. Moreover, laser-to-x-ray photon conversion efficiency (˜6 × 10-12) exceeds that of any previous LPA-based quasi-monoenergetic Compton source. Particle-in-cell simulations agree well with the measurements.

Therapeutic potential of cannabis in pain medicine.

PubMed

Hosking, R D; Zajicek, J P

2008-07-01

Advances in cannabis research have paralleled developments in opioid pharmacology whereby a psychoactive plant extract has elucidated novel endogenous signalling systems with therapeutic significance. Cannabinoids (CBs) are chemical compounds derived from cannabis. The major psychotropic CB delta-9-tetrahydrocannabinol (Delta(9)-THC) was isolated in 1964 and the first CB receptor (CB(1)R) was cloned in 1990. CB signalling occurs via G-protein-coupled receptors distributed throughout the body. Endocannabinoids are derivatives of arachidonic acid that function in diverse physiological systems. Neuronal CB(1)Rs modulate synaptic transmission and mediate psychoactivity. Immune-cell CB(2) receptors (CB(2)R) may down-regulate neuroinflammation and influence cyclooxygenase-dependent pathways. Animal models demonstrate that CBRs play a fundamental role in peripheral, spinal, and supraspinal nociception and that CBs are effective analgesics. Clinical trials of CBs in multiple sclerosis have suggested a benefit in neuropathic pain. However, human studies of CB-mediated analgesia have been limited by study size, heterogeneous patient populations, and subjective outcome measures. Furthermore, CBs have variable pharmacokinetics and can manifest psychotropism. They are currently licensed as antiemetics in chemotherapy and can be prescribed on a named-patient basis for neuropathic pain. Future selective peripheral CB(1)R and CB(2)R agonists will minimize central psychoactivity and may synergize opioid anti-nociception. This review discusses the basic science and clinical aspects of CB pharmacology with a focus on pain medicine.

Molecular and Biochemical Characterization of a Cathepsin B-Like Protease Family Unique to Trypanosoma congolense▿ †

PubMed Central

Mendoza-Palomares, Carlos; Biteau, Nicolas; Giroud, Christiane; Coustou, Virginie; Coetzer, Theresa; Authié, Edith; Boulangé, Alain; Baltz, Théo

2008-01-01

Cysteine proteases have been shown to be essential virulence factors and drug targets in trypanosomatids and an attractive antidisease vaccine candidate for Trypanosoma congolense. Here, we describe an important amplification of genes encoding cathepsin B-like proteases unique to T. congolense. More than 13 different genes were identified, whereas only one or two highly homologous genes have been identified in other trypanosomatids. These proteases grouped into three evolutionary clusters: TcoCBc1 to TcoCBc5 and TcoCBc6, which possess the classical catalytic triad (Cys, His, and Asn), and TcoCBs7 to TcoCBs13, which contains an unusual catalytic site (Ser, Xaa, and Asn). Expression profiles showed that members of the TcoCBc1 to TcoCBc5 and the TcoCBs7 to TcoCBs13 groups are expressed mainly in bloodstream forms and localize in the lysosomal compartment. The expression of recombinant representatives of each group (TcoCB1, TcoCB6, and TcoCB12) as proenzymes showed that TcoCBc1 and TcoCBc6 are able to autocatalyze their maturation 21 and 31 residues, respectively, upstream of the predicted start of the catalytic domain. Both displayed a carboxydipeptidase function, while only TcoCBc1 behaved as an endopeptidase. TcoCBc1 exhibited biochemical differences regarding inhibitor sensitivity compared to that of other cathepsin B-like proteases. Recombinant pro-TcoCBs12 did not automature in vitro, and the pepsin-matured enzyme was inactive in tests with cathepsin B fluorogenic substrates. In vivo inhibition studies using CA074Me (a cell-permeable cathepsin B-specific inhibitor) demonstrated that TcoCB are involved in lysosomal protein degradation essential for survival in bloodstream form. Furthermore, TcoCBc1 elicited an important immune response in experimentally infected cattle. We propose this family of proteins as a potential therapeutic target and as a plausible antigen for T. congolense diagnosis. PMID:18281598

3-Mercaptopyruvate Sulfurtransferase, Not Cystathionine β-Synthase Nor Cystathionine γ-Lyase, Mediates Hypoxia-Induced Migration of Vascular Endothelial Cells.

PubMed

Tao, Beibei; Wang, Rui; Sun, Chen; Zhu, Yichun

2017-01-01

Hypoxia-induced angiogenesis is a common phenomenon in many physiological and patho-physiological processes. However, the potential differential roles of three hydrogen sulfide producing systems cystathionine γ-lyase (CSE)/H 2 S, cystathionine β-synthase (CBS)/H 2 S, and 3-mercaptopyruvate sulfurtransferase (MPST)/H 2 S in hypoxia-induced angiogenesis are still unknown. We found that minor hypoxia (10% oxygen) significantly increased the migration of vascular endothelial cells while hypoxia (8% oxygen) significantly inhibited cell migration. The present study was performed using cells cultured in 10% oxygen. RNA interference was used to block the endogenous generation of hydrogen sulfide by CSE, CBS, or MPST in a vascular endothelial cell migration model in both normoxia and hypoxia. The results showed that CBS had a promoting effect on the migration of vascular endothelial cells cultured in both normoxic and hypoxic conditions. In contrast, CSE had an inhibitory effect on cell migration. MPST had a promoting effect on the migration of vascular endothelial cells cultured in hypoxia; however, it had no effect on the cells cultured in normoxia. Importantly, it was found that the hypoxia-induced increase in vascular endothelial cell migration was mediated by MPST, but not CSE or CBS. The western blot analyses showed that hypoxia significantly increased MPST protein levels, decreased CSE protein levels and did not change CBS levels, suggesting that these three hydrogen sulfide-producing systems respond differently to hypoxic conditions. Interestingly, MPST protein levels were elevated by hypoxia in a bi-phasic manner and MPST mRNA levels increased later than the first stage elevation of the protein levels, implying that the expression of MPST induced by hypoxia was also regulated at a post-transcriptional level. RNA pull-down assay showed that some candidate RNA binding proteins, such as nucleolin and Annexin A2, were dissociated from the 3'-UTR of MPST mRNA in hypoxia which implied their involvement in MPST mRNA regulation.

CBS Genome Atlas Database: a dynamic storage for bioinformatic results and sequence data.

PubMed

Hallin, Peter F; Ussery, David W

2004-12-12

Currently, new bacterial genomes are being published on a monthly basis. With the growing amount of genome sequence data, there is a demand for a flexible and easy-to-maintain structure for storing sequence data and results from bioinformatic analysis. More than 150 sequenced bacterial genomes are now available, and comparisons of properties for taxonomically similar organisms are not readily available to many biologists. In addition to the most basic information, such as AT content, chromosome length, tRNA count and rRNA count, a large number of more complex calculations are needed to perform detailed comparative genomics. DNA structural calculations like curvature and stacking energy, DNA compositions like base skews, oligo skews and repeats at the local and global level are just a few of the analysis that are presented on the CBS Genome Atlas Web page. Complex analysis, changing methods and frequent addition of new models are factors that require a dynamic database layout. Using basic tools like the GNU Make system, csh, Perl and MySQL, we have created a flexible database environment for storing and maintaining such results for a collection of complete microbial genomes. Currently, these results counts to more than 220 pieces of information. The backbone of this solution consists of a program package written in Perl, which enables administrators to synchronize and update the database content. The MySQL database has been connected to the CBS web-server via PHP4, to present a dynamic web content for users outside the center. This solution is tightly fitted to existing server infrastructure and the solutions proposed here can perhaps serve as a template for other research groups to solve database issues. A web based user interface which is dynamically linked to the Genome Atlas Database can be accessed via www.cbs.dtu.dk/services/GenomeAtlas/. This paper has a supplemental information page which links to the examples presented: www.cbs.dtu.dk/services/GenomeAtlas/suppl/bioinfdatabase.

Therapeutic Effects of Rivastigmine and Alfa-Lipoic Acid Combination in the Charles Bonnet Syndrome: Electroencephalography Correlates.

PubMed

Hanoglu, Lutfu; Yildiz, Sultan; Polat, Burcu; Demirci, Sema; Tavli, Ahmet Mithat; Yilmaz, Nesrin; Yulug, Burak

2016-01-01

Charles Bonnet Syndrome (CBS) is a rare clinical condition which is characterized by complex hallucinations in visually impaired patients. The pathophysiology of this disorder remains largely unknown, and there is still no proven treatment for this disease. In our study, we aimed to investigate the neural activity through Electroencephalography (EEG) power and evaluate the effect of rivastigmine in combination with alpha-lipoic acid on hallucination in two CBS patients with diabetic retinopathy. EEG data was recorded with standard routine EEG protocols for both patients in our electrophysiological research laboratory (REMER Clinical Electrophysiology and Neuromodulation Research and Application Laboratory) with Brain Vision Recorder (Brainproduct, Munich, Germany). All spectral analyses were processed by BrainVision Analyzer 2 (Brainproduct, Munich, Germany, 2.0.4 Version) in 128 Hz sample rates and the EEG recording and analysis was performed before the administration of rivastigmine (4.5 mg/daily and five patch daily for the first and second patients, respectively) in combination with alpha-lipoic acid (600 mg/daily) for both patients while they were not hallucinated during the time period recordings. Based on our measurement protocol, we have compared the patients in the study group with the three control subjects who were found to be normal except of visual disturbances secondary to significant diabetic retinopathy. Highest theta power values were found in right occipital and left temporo-parietal regions for first and second CBS patients, respectively. Additionally, power spectra were lower in two cases as compared to their control groups in the alpha band for all electrodes. We have also shown that acid rivastigmine in combination with alpha-lipoic exerted significant anti-hallucinatory efficiency. Our present findings could support the hypothesis that increased activation of specific areas in the source monitoring system plays an important role in the pathogenesis of CBS. In addition, rivastigmine in combination with alpha-lipoic acid could be a new valuable option for CBS patients.

A Method to Retrieve Rainfall Rate over Land from TRMM Observations

NASA Technical Reports Server (NTRS)

Prabhakara, C.; Iacovazzi, R., Jr.; Yoo, J.-M.

2002-01-01

Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR) observations over mesoscale convective systems (MCSs) reveal that there are localized maxima in the rain rate with a scale of about 10 to 20 km that represent thunderstorms (Cbs). Some of these Cbs are developing or intense, while others are decaying or weak. These Cbs constitute only about 20 % of the rain area of a given MCS. Outside of Cbs, the average rain rate is much weaker than that within Cbs. From an analysis of the PR data, we find that the spatial distribution of rain and its character, convective or stratiform, is highly inhomogeneous. This complex nature of rain exists on a scale comparable to that of a Cb. The 85 GHz brightness temperature, T85, observations of the TRMM Microwave Imager (TMI) radiometer taken over an MCS reflect closely the PR rain rate pattern over land. Local maxima in rain rate shown by PR are observed as local minima in T85. Where there are no minima in T85, PR observations indicate there is light rain. However, the TMI brightness temperature measurements (Tbs) have poor ability to discriminate convective rain from stratiform rain. For this reason, a TMI rain retrieval procedure that depends primarily on the magnitude of Tbs performs poorly. In order to retrieve rain rate from TMI data on land one has to include the spatial distribution information deduced from the T85 data in the retrieval method. Then, quantitative estimation of rain rate can be accomplished. A TMI rain retrieval method developed along these lines can yield estimates of rain rate and its frequency distribution which agree closely with that given by PR. We find the current TRMM project TMI (Version 5) rain retrieval algorithm on land could be improved with the retrieval scheme developed here. To support the conceptual frame work of the rain retrieval method developed here, a theoretical analysis of the TMI brightness temperatures in convective and stratiform regions is presented.

Associations between homocysteine metabolism related SNPs and carotid intima-media thickness: a Chinese sib pair study.

PubMed

Sun, Kexin; Song, Jing; Liu, Kuo; Fang, Kai; Wang, Ling; Wang, Xueyin; Li, Jing; Tang, Xun; Wu, Yiqun; Qin, Xueying; Wu, Tao; Gao, Pei; Chen, Dafang; Hu, Yonghua

2017-04-01

Carotid intima-media thickness (CIMT) is a good surrogate for atherosclerosis. Hyperhomocysteinemia is an independent risk factor for cardiovascular diseases. We aim to investigate the relationships between homocysteine (Hcy) related biochemical indexes and CIMT, the associations between Hcy related SNPs and CIMT, as well as the potential gene-gene interactions. The present study recruited full siblings (186 eligible families with 424 individuals) with no history of cardiovascular events from a rural area of Beijing. We examined CIMT, intima-media thickness for common carotid artery (CCA-IMT) and carotid bifurcation, tested plasma levels for Hcy, vitamin B6 (VB6), vitamin B12 (VB12) and folic acid (FA), and genotyped 9 SNPs on MTHFR, MTR, MTRR, BHMT, SHMT1, CBS genes. Associations between SNPs and biochemical indexes and CIMT indexes were analyzed using family-based association test analysis. We used multi-level mixed-effects regression model to verify SNP-CIMT associations and to explore the potential gene-gene interactions. VB6, VB12 and FA were negatively correlated with CIMT indexes (p < 0.05). rs2851391 T allele was associated with decreased plasma VB12 levels (p = 0.036). In FABT, CBS rs2851391 was significantly associated with CCA-IMT (p = 0.021) and CIMT (p = 0.019). In multi-level mixed-effects regression model, CBS rs2851391 was positively significantly associated with CCA-IMT (Coef = 0.032, se = 0.009, raw p < 0.001) after Bonferoni correction (corrected α = 0.0056). Gene-gene interactions were found between CBS rs2851391 and BHMT rs10037045 for CCA-IMT (p = 0.011), as well as between CBS rs2851391 and MTR rs1805087 for CCA-IMT (p = 0.007) and CIMT (p = 0.022). Significant associations are found between Hcy metabolism related genetic polymorphisms, biochemical indexes and CIMT indexes. There are complex interactions between genetic polymorphisms for CCA-IMT and CIMT.

Phylogenetic analysis of phenotypically characterized Cryptococcus laurentii isolates reveals high frequency of cryptic species.

PubMed

Ferreira-Paim, Kennio; Ferreira, Thatiana Bragine; Andrade-Silva, Leonardo; Mora, Delio Jose; Springer, Deborah J; Heitman, Joseph; Fonseca, Fernanda Machado; Matos, Dulcilena; Melhem, Márcia Souza Carvalho; Silva-Vergara, Mario León

2014-01-01

Although Cryptococcus laurentii has been considered saprophytic and its taxonomy is still being described, several cases of human infections have already reported. This study aimed to evaluate molecular aspects of C. laurentii isolates from Brazil, Botswana, Canada, and the United States. In this study, 100 phenotypically identified C. laurentii isolates were evaluated by sequencing the 18S nuclear ribosomal small subunit rRNA gene (18S-SSU), D1/D2 region of 28S nuclear ribosomal large subunit rRNA gene (28S-LSU), and the internal transcribed spacer (ITS) of the ribosomal region. BLAST searches using 550-bp, 650-bp, and 550-bp sequenced amplicons obtained from the 18S-SSU, 28S-LSU, and the ITS region led to the identification of 75 C. laurentii strains that shared 99-100% identity with C. laurentii CBS 139. A total of nine isolates shared 99% identity with both Bullera sp. VY-68 and C. laurentii RY1. One isolate shared 99% identity with Cryptococcus rajasthanensis CBS 10406, and eight isolates shared 100% identity with Cryptococcus sp. APSS 862 according to the 28S-LSU and ITS regions and designated as Cryptococcus aspenensis sp. nov. (CBS 13867). While 16 isolates shared 99% identity with Cryptococcus flavescens CBS 942 according to the 18S-SSU sequence, only six were confirmed using the 28S-LSU and ITS region sequences. The remaining 10 shared 99% identity with Cryptococcus terrestris CBS 10810, which was recently described in Brazil. Through concatenated sequence analyses, seven sequence types in C. laurentii, three in C. flavescens, one in C. terrestris, and one in the C. aspenensis sp. nov. were identified. Sequencing permitted the characterization of 75% of the environmental C. laurentii isolates from different geographical areas and the identification of seven haplotypes of this species. Among sequenced regions, the increased variability of the ITS region in comparison to the 18S-SSU and 28S-LSU regions reinforces its applicability as a DNA barcode.

Natural and laboratory compaction bands in porous carbonates: a three-dimensional characterization using synchrotron X-ray computed microtomography

NASA Astrophysics Data System (ADS)

Cilona, A.; Arzilli, F.; Mancini, L.; Emanuele, T.

2014-12-01

Porous carbonates form important reservoirs for water and hydrocarbons. The fluid flow properties of carbonate reservoirs may be affected by post-depositional processes (e.g., mechanical and chemical), which need to be quantified. Field-based studies described bed-parallel compaction bands (CBs) within carbonates with a wide range of porosities. These burial-related structures accommodate volumetric strain by grain rotation, translation, pore collapse and pressure solution. Recently, the same structures have been reproduced for the first time in the laboratory by performing triaxial compaction experiments on porous grainstones. These laboratory studies characterized and compared the microstructures of natural and laboratory CBs, but no analysis of pore connectivity has been performed. In this paper, we use an innovative approach to characterize the pore networks (e.g. porosity, connectivity) of natural and laboratory CBs and compare them with the host rock one. We collected the data using the synchrotron X-ray computed microtomography technique at the SYRMEP beamline of the Elettra-Sincrotrone Trieste Laboratory (Italy). Quantitative analyses of the samples were performed with the Pore3D software library. The porosity was calculated from segmented 3D images of pristine and deformed carbonates. A process of skeletonization was then applied to quantify the number of connected pores within the rock volume. The analysis of the skeleton allowed us to highlight the differences between natural and laboratory CBs, and to investigate how pore connectivity evolves as a function of different deformation pathways. Both pore volume and connectivity are reduced within the CBs respect to the pristine rock and the natural CB has a lower porosity with respect to the laboratory one. The grain contacts in the natural CB are welded, whereas in the laboratory one they have more irregular shapes and grain crushing is the predominant process.

Cost Structure and Life Cycle Costs for Military Systems

DTIC Science & Technology

2003-09-01

LCC 1-1 Chapter 2 – Scope of the Study 2-1 2.1 Contribution of other NATO Entities 2-1 2.2 Review of National Practises and CBS 2-1 2.3 Development...Office – NCO) gave a positive answer and designated a representative in the working group. 2.2 REVIEW OF NATIONAL PRACTISES AND CBS The two first...time preference when spending money obtained through taxation ) with the effectiveness of alternate ways of meeting an objective. By combining the

Simultaneous saccharification and fermentation (SSF) using cellobiose fermenting yeast Brettanomyces custersii (CBS 5512)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Spindler, D.D.; Grohmann, K.; Wyman, C.E.

1991-01-16

A process for producing ethanol from plant biomass includes forming a substrate from the biomass with the substrate including hydrolysates of cellulose and hemicellulose. A species of the yeast Brettanomyces custersii (CBS 5512), which has the ability to ferment both cellobiose and glucose to ethanol, is then selected and isolated. The substrate is inoculated with this yeast, and the inoculated substrate is then fermented under conditions favorable for cell viability and conversion of hydrolysates to ethanol.

Studies of the synthesis and deposition of Cu3BiS 3 for use in photovoltaic devices

NASA Astrophysics Data System (ADS)

Epstein, Joshua A.

As the world's climate continues to change, alternative energy is being adopted more and more. Solar energy is one extremely promising candidate to supplement our ever increasing energy needs. In order for it to be a viable solution, more efficient and less expensive solar panels must be made. While silicon solar panels are the current market leader their high manufacturing energy input and cost warrant looking into alternatives. Many thin film solar materials are being investigated such as CdTe, CIGS and CZTS, but all come with their own drawbacks. With a near ideal band gap, low toxicity and earth abundant elemental make up copper bismuth sulfide, Cu3BiS3, is a promising candidate for use in future photovoltaic devices. The research presented here details multiple methods to synthesize and deposit this material with an effort to keep the methods low cost, energy efficient and environmentally friendly. Multiple low temperature solvothermal routes to synthesizing copper bismuth sulfide, CBS, have been developed. The resulting powders have been verified as pure Cu3BiS3 via XRD peak matching. The precursor reactants tested for use were copper and bismuth nitrates, acetates, chlorides and hydroxides. L-cystine, L-cysteine, thiourea and CS2 have all been tested for use as sulfur sources. Seven of these combinations produced pure CBS powders. Two custom built benchtop reactors have been designed and fabricated with the aim of studying the possibility of a continuous flow reactor as a way to utilize these precipitation chemistries for making thin films of CBS. Heat and liquid flow simulations were performed in COMSOL multiphysics to assist in the reactor design process. The second reactor was designed to promote uniform liquid flow across the fluorine doped, tin oxide coated, FTO, glass. This reactor was also built with a temperature gradient transverse to the liquid flow so that the optimal temperature for the deposition of CBS could be evaluated. This reactor was also used to evaluate the deposition of CdS, an n-type semiconductor often used in thin film solar panels, onto FTO glass. CBS thin films were also prepared via electrodeposition and thermal treatment. The solution used was a mixture of copper nitrate, sodium sulfite and sodium citrate tribasic dihydrate dissolved in DI H2O and bismuth nitrate dissolved in ethylene glycol. To get the best coating it was found that the electrodeposition should be done at 1.2 V and last 5 minutes. Thermal treatment carried out in a 450°C tube furnace for 90 min in forming gas (95% N2 with 5% H2) along with sulfur vapor was proved best. No further treatment was required to obtain phase pure CBS coatings. This was verified with XRD peak analysis. Optical absorption, microstructural, and photoconductivity data are reported for CBS materials made using the above techniques.

Discriminative potential of some PCR-based and biochemical methods at Scedosporium strains.

PubMed

Kraková, Lucia; Pangallo, Domenico; Piecková, Elena; Majorošová, Mária

2016-02-01

Three innovative PCR-based methods (fluorescent-ITS, fluorescent-CBH and ITS-PCR DGGE) were tested using a reference set of nine strains of Scedosporium from the CBS fungal collection. Cellulolytic, lipolytic and proteolytic potential and the ability to dissolve CaCO3 of the strains were evaluated in vitro by means of agar assays. f-ITS profiles almost recognized main species, although included "Pseudallescheria" ellipsoidea and the Scedosporium boydii CBS 117432 and CBS 120157 in the same cluster. All strains successfully produced DNA polymorphisms by f-CBH amplification which divided them into three different groups. The DGGE approach separated the strains studied into other five clusters which in some case were not matching with species. Strains tested were monomorphic in possessing strong proteolytic and lipolytic activities. The comparison of the three PCR-based genotyping approaches, together with biodegradation ability screening, displayed an intraspecies variability in S. boydii, interfering with unambiguous species delimitation. Copyright © 2015 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

Simplified Modeling of Steady-State and Transient Brillouin Gain in Magnetoactive Non-Centrosymmetric Semiconductors

NASA Astrophysics Data System (ADS)

Singh, M.; Aghamkar, P.; Sen, P. K.

With the aid of a hydrodynamic model of semiconductor-plasmas, a detailed analytical investigation is made to study both the steady-state and the transient Brillouin gain in magnetized non-centrosymmetric III-V semiconductors arising from the nonlinear interaction of an intense pump beam with the internally-generated acoustic wave, due to piezoelectric and electrostrictive properties of the crystal. Using the fact that the origin of coherent Brillouin scattering (CBS) lies in the third-order (Brillouin) susceptibility of the medium, we obtained an expression of the gain coefficient of backward Stokes mode in steady-state and transient regimes and studied the dependence of piezoelectricity, magnetic field and pump pulse duration on its growth rate. The threshold-pump intensity and optimum pulse duration for the onset of transient CBS are estimated. The piezoelectricity and externally-applied magnetic field substantially enhances the transient CBS gain coefficient in III-V semiconductors which can be of great use in the compression of scattered pulses.

Noncovalent Interactions of DNA Bases with Naphthalene and Graphene.

PubMed

Cho, Yeonchoo; Min, Seung Kyu; Yun, Jeonghun; Kim, Woo Youn; Tkatchenko, Alexandre; Kim, Kwang S

2013-04-09

The complexes of a DNA base bound to graphitic systems are studied. Considering naphthalene as the simplest graphitic system, DNA base-naphthalene complexes are scrutinized at high levels of ab initio theory including coupled cluster theory with singles, doubles, and perturbative triples excitations [CCSD(T)] at the complete basis set (CBS) limit. The stacked configurations are the most stable, where the CCSD(T)/CBS binding energies of guanine, adenine, thymine, and cytosine are 9.31, 8.48, 8.53, 7.30 kcal/mol, respectively. The energy components are investigated using symmetry-adapted perturbation theory based on density functional theory including the dispersion energy. We compared the CCSD(T)/CBS results with several density functional methods applicable to periodic systems. Considering accuracy and availability, the optB86b nonlocal functional and the Tkatchenko-Scheffler functional are used to study the binding energies of nucleobases on graphene. The predicted values are 18-24 kcal/mol, though many-body effects on screening and energy need to be further considered.

Hydrogen sulfide-mediated regulation of contractility in the mouse ileum with electrical stimulation: roles of L-cysteine, cystathionine β-synthase, and K+ channels.

PubMed

Yamane, Satoshi; Kanno, Toshio; Nakamura, Hiroyuki; Fujino, Hiromichi; Murayama, Toshihiko

2014-10-05

Hydrogen sulfide (H2S) is considered to be a signaling molecule. The precise mechanisms underlying H2S-related events, including the producing enzymes and target molecules in gastrointestinal tissues, have not been elucidated in detail. We herein examined the involvement of H2S in contractions induced by repeated electrical stimulations (ES). ES-induced contractions were neurotoxin-sensitive and increased by aminooxyacetic acid, an inhibitor of cystathionine β-synthase (CBS) and cystathionine γ-lyase, but not by D,L-propargylglycine, a selective inhibitor of cystathionine γ-lyase, in an ES trial-dependent manner. ES-induced contractions were markedly decreased in the presence of L-cysteine. This response was inhibited by aminooxyacetic acid and an antioxidant, and accelerated by L-methionine, an activator of CBS. The existence of CBS was confirmed. NaHS transiently inhibited ES- and acetylcholine-induced contractions, and sustainably decreased basal tone for at least 20 min after its addition. The treatment with glibenclamide, an ATP-sensitive K+ channel blocker, reduced both the L-cysteine response and NaHS-induced inhibition of contractions. The NaHS-induced decrease in basal tone was inhibited by apamin, a small conductance Ca2+-activated K+ channel blocker. These results suggest that H2S may be endogenously produced via CBS in ES-activated enteric neurons, and regulates contractility via multiple K+ channels in the ileum. Copyright © 2014 Elsevier B.V. All rights reserved.

Genetic basis of Bartter syndrome in Korea.

PubMed

Lee, Beom Hee; Cho, Hee Yeon; Lee, HyunKyung; Han, Kyoung Hee; Kang, Hee Gyung; Ha, Il Soo; Lee, Joo Hoon; Park, Young Seo; Shin, Jae Il; Lee, Dae-Yeol; Kim, Su-Yung; Choi, Yong; Cheong, Hae Il

2012-04-01

Bartter syndrome (BS) is clinically classified into antenatal or neonatal BS (aBS) and classic BS (cBS) as well as five subtypes based on the underlying mutant gene; SLC12A1 (BS I), KCNJ1 (BS II), CLCNKB (BS III), BSND (BS IV) and CASR (BS V). Clinico-genetic features of a nationwide cohort of 26 Korean children with BS were investigated. The clinical diagnosis was aBS in 8 (30.8%), cBS in 15 (57.7%) and mixed Bartter-Gitelman phenotype in 3 cases (11.5%). Five of eight patients with aBS and all 18 patients with either cBS or mixed Bartter-Gitelman phenotype had CLCNKB mutations. Among the 23 patients (46 alleles) with CLCNKB mutations, p.W610X and large deletions were detected in 25 (54.3%) and 10 (21.7%) alleles, respectively. There was no genotype-phenotype correlation in patients with CLCNKB mutations. Twenty-three (88.5%) of the 26 BS patients involved in this study had CLCNKB mutations. The p.W610X mutation and large deletion were two common types of mutations in CLCNKB. The clinical manifestations of BS III were heterogeneous without a genotype-phenotype correlation, typically manifesting cBS phenotype but also aBS or mixed Bartter-Gitelman phenotypes. The molecular diagnostic steps for patients with BS in our population should be designed taking these peculiar genotype distributions into consideration, and a new more clinically relevant classification including BS and Gitelman syndrome is required.

Urothelium muscarinic activation phosphorylates CBS(Ser227) via cGMP/PKG pathway causing human bladder relaxation through H2S production.

PubMed

d'Emmanuele di Villa Bianca, Roberta; Mitidieri, Emma; Fusco, Ferdinando; Russo, Annapina; Pagliara, Valentina; Tramontano, Teresa; Donnarumma, Erminia; Mirone, Vincenzo; Cirino, Giuseppe; Russo, Giulia; Sorrentino, Raffaella

2016-08-11

The urothelium modulates detrusor activity through releasing factors whose nature has not been clearly defined. Here we have investigated the involvement of H2S as possible mediator released downstream following muscarinic (M) activation, by using human bladder and urothelial T24 cell line. Carbachol stimulation enhances H2S production and in turn cGMP in human urothelium or in T24 cells. This effect is reversed by cysthationine-β-synthase (CBS) inhibition. The blockade of M1 and M3 receptors reverses the increase in H2S production in human urothelium. In T24 cells, the blockade of M1 receptor significantly reduces carbachol-induced H2S production. In the functional studies, the urothelium removal from human bladder strips leads to an increase in carbachol-induced contraction that is mimicked by CBS inhibition. Instead, the CSE blockade does not significantly affect carbachol-induced contraction. The increase in H2S production and in turn of cGMP is driven by CBS-cGMP/PKG-dependent phosphorylation at Ser(227) following carbachol stimulation. The finding of the presence of this crosstalk between the cGMP/PKG and H2S pathway downstream to the M1/M3 receptor in the human urothelium further implies a key role for H2S in bladder physiopathology. Thus, the modulation of the H2S pathway can represent a feasible therapeutic target to develop drugs for bladder disorders.

Compact tunable Compton x-ray source from laser-plasma accelerator and plasma mirror

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tsai, Hai-En; Wang, Xiaoming; Shaw, Joseph M.

2015-02-15

We present an in-depth experimental-computational study of the parameters necessary to optimize a tunable, quasi-monoenergetic, efficient, low-background Compton backscattering (CBS) x-ray source that is based on the self-aligned combination of a laser-plasma accelerator (LPA) and a plasma mirror (PM). The main findings are (1) an LPA driven in the blowout regime by 30 TW, 30 fs laser pulses produce not only a high-quality, tunable, quasi-monoenergetic electron beam, but also a high-quality, relativistically intense (a{sub 0} ∼ 1) spent drive pulse that remains stable in profile and intensity over the LPA tuning range. (2) A thin plastic film near the gas jetmore » exit retro-reflects the spent drive pulse efficiently into oncoming electrons to produce CBS x-rays without detectable bremsstrahlung background. Meanwhile, anomalous far-field divergence of the retro-reflected light demonstrates relativistic “denting” of the PM. Exploiting these optimized LPA and PM conditions, we demonstrate quasi-monoenergetic (50% FWHM energy spread), tunable (75–200 KeV) CBS x-rays, characteristics previously achieved only on more powerful laser systems by CBS of a split-off, counter-propagating pulse. Moreover, laser-to-x-ray photon conversion efficiency (∼6 × 10{sup −12}) exceeds that of any previous LPA-based quasi-monoenergetic Compton source. Particle-in-cell simulations agree well with the measurements.« less

Hoarding in a compulsive buying sample.

PubMed

Mueller, Astrid; Mueller, Ulrike; Albert, Patricia; Mertens, Christian; Silbermann, Andrea; Mitchell, James E; de Zwaan, Martina

2007-11-01

Previous research has indicated that many compulsive buyers also suffer from compulsive hoarding. The present work specifically examined hoarding in a compulsive buying sample. Sixty-six treatment-seeking compulsive buyers were assessed prior to entering a group therapy for compulsive buying using the Compulsive Buying Scale (CBS), the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS)-Shopping Version, the Compulsive Acquisition Scale (CAS), the German-CBS, the Saving Inventory-Revised (SI-R), the Maudsley Obsessive Compulsive Inventory (MOCI), the Barratt Impulsiveness Scale (BIS-11), and the Structured Clinical Interview for DSM-IV Axis I (SCID). Inclusion criteria were current problems with compulsive buying according to the proposed diagnostic criteria for compulsive buying by McElroy, Keck, Pope, Smith, and Strakowski [(1994). Compulsive buying: A report of 20 cases. Journal of Clinical Psychiatry, 55, 242-248]. Our results support the assumption that many but not all compulsive buyers suffer from compulsive hoarding. A significant association between the SI-R and the compulsive buying measures CBS, Y-BOCS-SV, German-CBS, and the CAS-Buy subscale was found, which is mostly caused by the SI-R subscale acquisition. The SI-R subscales clutter and difficulty discarding were more closely associated with the CAS-Free subscale and with obsessive-compulsive symptoms. Hoarding compulsive buyers reported more severe buying symptoms and obsessive-compulsive symptoms and presented with a higher psychiatric co-morbidity, especially any current affective, anxiety and eating disorder. Specific therapeutic interventions for compulsive buyers who also report compulsive hoarding appear indicated.

Insight into microtubule destabilization mechanism of 3,4,5-trimethoxyphenyl indanone derivatives using molecular dynamics simulation and conformational modes analysis

NASA Astrophysics Data System (ADS)

Tripathi, Shubhandra; Srivastava, Gaurava; Singh, Aastha; Prakasham, A. P.; Negi, Arvind S.; Sharma, Ashok

2018-03-01

Colchicine site inhibitors are microtubule destabilizers having promising role in cancer therapeutics. In the current study, four such indanone derivatives (t1, t9, t14 and t17) with 3,4,5-trimethoxyphenyl fragment (ring A) and showing significant microtubule destabilization property have been explored. The interaction mechanism and conformational modes triggered by binding of these indanone derivatives and combretastatin at colchicine binding site (CBS) of αβ-tubulin dimer were studied using molecular dynamics (MD) simulation, principle component analysis and free energy landscape analysis. In the MD results, t1 showed binding similar to colchicine interacting in the deep hydrophobic core at the CBS. While t9, t14 and t17 showed binding conformation similar to combretastatin, with ring A superficially binding at the CBS. Results demonstrated that ring A played a vital role in binding via hydrophobic interactions and got anchored between the S8 and S9 sheets, H8 helix and T7 loop at the CBS. Conformational modes study revealed that twisting and bending conformational motions (as found in the apo system) were nearly absent in the ligand bound systems. Absence of twisting motion might causes loss of lateral contacts in microtubule, thus promoting microtubule destabilization. This study provides detailed account of microtubule destabilization mechanism by indanone ligands and combretastatin, and would be helpful for designing microtubule destabilizers with higher activity.

A Comparison of Quantum and Molecular Mechanical Methods to Estimate Strain Energy in Druglike Fragments.

PubMed

Sellers, Benjamin D; James, Natalie C; Gobbi, Alberto

2017-06-26

Reducing internal strain energy in small molecules is critical for designing potent drugs. Quantum mechanical (QM) and molecular mechanical (MM) methods are often used to estimate these energies. In an effort to determine which methods offer an optimal balance in accuracy and performance, we have carried out torsion scan analyses on 62 fragments. We compared nine QM and four MM methods to reference energies calculated at a higher level of theory: CCSD(T)/CBS single point energies (coupled cluster with single, double, and perturbative triple excitations at the complete basis set limit) calculated on optimized geometries using MP2/6-311+G**. The results show that both the more recent MP2.X perturbation method as well as MP2/CBS perform quite well. In addition, combining a Hartree-Fock geometry optimization with a MP2/CBS single point energy calculation offers a fast and accurate compromise when dispersion is not a key energy component. Among MM methods, the OPLS3 force field accurately reproduces CCSD(T)/CBS torsion energies on more test cases than the MMFF94s or Amber12:EHT force fields, which struggle with aryl-amide and aryl-aryl torsions. Using experimental conformations from the Cambridge Structural Database, we highlight three example structures for which OPLS3 significantly overestimates the strain. The energies and conformations presented should enable scientists to estimate the expected error for the methods described and we hope will spur further research into QM and MM methods.

Fungicide resistance and genetic variability in plant pathogenic strains of Guignardia citricarpa

PubMed Central

Possiede, Y.M.; Gabardo, J.; Kava-Cordeiro, V.; Galli-Terasawa, L.V.; Azevedo, J.L.; Glienke, C.

2009-01-01

Citrus black spot (CBS) is a plant disease of worldwide occurrence, affecting crops in Africa, Oceania, and South America. In Brazil, climate provides favorable conditions and CBS has spread to the Southeast and South regions. CBS is caused by the fungus Guignardia citricarpa (anamorph: Phyllosticta citricarpa) and its control is based on the use of fungicides, such as benzimidazoles. In South Africa, the disease was kept under control for 10 years with benomyl, until cases of resistance to high concentrations of this fungicide were reported from all citrus-producing areas. Azoxystrobin (a strobilurin) has been found effective in controlling phytopathogens, including CBS, in a wide range of economically important crops. The present study investigated in vitro the effects of the fungicides benomyl and azoxystrobin on 10 strains of G. citricarpa isolated from lesions in citrus plants from Brazil and South Africa. Benomyl at 0.5 μg/mL inhibited mycelial growth in all strains except PC3C, of African origin, which exhibited resistance to concentrations of up to 100.0 μg/mL. The spontaneous mutation frequency for resistance to benomyl was 1.25 × 10-7. Azoxystrobin, even at high concentrations, did not inhibit mycelial growth in any of the strains, but significantly reduced sporulation rates, by as much as 100%, at a concentration of 5.0 μg/mL. Variations in sensitivity across strains, particularly to the strobilurin azoxystrobin, are possibly related to genetic variability in G. citricarpa isolates. PMID:24031363

Direction of R&D and Current Status of Understanding of Advanced Gear Steels

DTIC Science & Technology

1986-02-01

our laboratory. A-Z 9-4 CBS600 was developed by Timken as a carburizing grade bearing steel for service above 150C. The philosophy used in designing...melted (VIM-VAR) steels . The effect of long time aging at 230C on the Charpy energy for CBS600 is currently underway at AMMRC. M50 NIL General Electric, in...contact fatigue life and hot hardness as high as for P50 (the high hot hardness bearing steel widely used in aircraft gas turbine engines in the USA) the

Isolation and identification of a thermophilic strain producing trehalose synthase from geothermal water in China.

PubMed

Zhu, Yueming; Zhang, Jun; Wei, Dongsheng; Wang, Yufan; Chen, Xiaoyun; Xing, Laijun; Li, Mingchun

2008-08-01

A slightly thermophilic strain, CBS-01, producing trehalose synthase (TreS), was isolated from geothermal water in this study. According to the phenotypic characteristics and phylogenetic analysis of the 16s rRNA gene sequence, it was identified as Meiothermus ruber. The trehalose synthase gene of Meiothermus ruber CBS-01 was cloned by polymerase chain reaction and sequenced. The TreS gene consisted of 2,895 nucleotides, which specified a 964-amino-acid protein. This novel TreS catalyzed reversible interconversion of maltose and trehalose.

In Rwandese Women with Low Iron Status, Iron Absorption from Low-Phytic Acid Beans and Biofortified Beans Is Comparable, but Low-Phytic Acid Beans Cause Adverse Gastrointestinal Symptoms.

PubMed

Petry, Nicolai; Rohner, Fabian; Gahutu, Jean Bosco; Campion, Bruno; Boy, Erick; Tugirimana, Pierrot L; Zimmerman, Michael Bruce; Zwahlen, Christian; Wirth, James P; Moretti, Diego

2016-05-01

Phytic acid (PA) is a major inhibitor of iron bioavailability from beans, and high PA concentrations might limit the positive effect of biofortified beans (BBs) on iron status. Low-phytic acid (lpa) bean varieties could increase iron bioavailability. We set out to test whether lpa beans provide more bioavailable iron than a BB variety when served as part of a composite meal in a bean-consuming population with low iron status. Dietary iron absorption from lpa, iron-biofortified, and control beans (CBs) (regular iron and PA concentrations) was compared in 25 nonpregnant young women with low iron status with the use of a multiple-meal crossover design. Iron absorption was measured with stable iron isotopes. PA concentration in lpa beans was ∼10% of BBs and CBs, and iron concentration in BBs was ∼2- and 1.5-fold compared with CBs and lpa beans, respectively. Fractional iron absorption from lpa beans [8.6% (95% CI: 4.8%, 15.5%)], BBs [7.3% (95% CI: 4.0%, 13.4%)], and CBs [8.0% (95% CI: 4.4%, 14.6%)] did not significantly differ. The total amount of iron absorbed from lpa beans and BBs was 421 μg (95% CI: 234, 756 μg) and 431 μg (95% CI: 237, 786 μg), respectively, and did not significantly differ, but was >50% higher (P < 0.005) than from CBs (278 μg; 95% CI: 150, 499 μg). In our trial, the lpa beans were hard to cook, and their consumption caused transient adverse digestive side effects in ∼95% of participants. Gel electrophoresis analysis showed phytohemagglutinin L (PHA-L) residues in cooked lpa beans. BBs and lpa beans provided more bioavailable iron than control beans and could reduce dietary iron deficiency. Digestive side effects of lpa beans were likely caused by PHA-L, but it is unclear to what extent the associated digestive problems reduced iron bioavailability. This trial was registered at clinicaltrials.gov as NCT02215278. © 2016 American Society for Nutrition.

Phylogenetic Analysis of Phenotypically Characterized Cryptococcus laurentii Isolates Reveals High Frequency of Cryptic Species

PubMed Central

Ferreira-Paim, Kennio; Ferreira, Thatiana Bragine; Andrade-Silva, Leonardo; Mora, Delio Jose; Springer, Deborah J.; Heitman, Joseph; Fonseca, Fernanda Machado; Matos, Dulcilena; Melhem, Márcia Souza Carvalho; Silva-Vergara, Mario León

2014-01-01

Background Although Cryptococcus laurentii has been considered saprophytic and its taxonomy is still being described, several cases of human infections have already reported. This study aimed to evaluate molecular aspects of C. laurentii isolates from Brazil, Botswana, Canada, and the United States. Methods In this study, 100 phenotypically identified C. laurentii isolates were evaluated by sequencing the 18S nuclear ribosomal small subunit rRNA gene (18S-SSU), D1/D2 region of 28S nuclear ribosomal large subunit rRNA gene (28S-LSU), and the internal transcribed spacer (ITS) of the ribosomal region. Results BLAST searches using 550-bp, 650-bp, and 550-bp sequenced amplicons obtained from the 18S-SSU, 28S-LSU, and the ITS region led to the identification of 75 C. laurentii strains that shared 99–100% identity with C. laurentii CBS 139. A total of nine isolates shared 99% identity with both Bullera sp. VY-68 and C. laurentii RY1. One isolate shared 99% identity with Cryptococcus rajasthanensis CBS 10406, and eight isolates shared 100% identity with Cryptococcus sp. APSS 862 according to the 28S-LSU and ITS regions and designated as Cryptococcus aspenensis sp. nov. (CBS 13867). While 16 isolates shared 99% identity with Cryptococcus flavescens CBS 942 according to the 18S-SSU sequence, only six were confirmed using the 28S-LSU and ITS region sequences. The remaining 10 shared 99% identity with Cryptococcus terrestris CBS 10810, which was recently described in Brazil. Through concatenated sequence analyses, seven sequence types in C. laurentii, three in C. flavescens, one in C. terrestris, and one in the C. aspenensis sp. nov. were identified. Conclusions Sequencing permitted the characterization of 75% of the environmental C. laurentii isolates from different geographical areas and the identification of seven haplotypes of this species. Among sequenced regions, the increased variability of the ITS region in comparison to the 18S-SSU and 28S-LSU regions reinforces its applicability as a DNA barcode. PMID:25251413

Bioaccumulation of hydroxylated polychlorinated biphenyls and pentachlorophenol in the serum of northern elephant seal pups (Mirounga angustirostris)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Louis, Caroline, E-mail: caroline.louis@uclouvain.be; Covaci, Adrian; Stas, Marie

Northern elephant seals (NES) (Mirounga angustirostris) from the Año Nuevo State Reserve (CA, USA) were sampled at 1-, 4-, 7- and 10-week post-weaning. Concentrations of hydroxylated polychlorinated biphenyls (HO-PCBs) and their parent PCBs were measured in the serum of each individual. The ΣHO-PCB concentrations in the serum increased significantly between early and late fast (from 282±20 to 529±31 pg/mL). This increase might result from a mobilisation of HO-PCBs transferred from the mother during gestation and/or lactation and stored in the pup's liver. Food deprivation has been shown to exacerbate biotransformation capacities in mammals, birds and fish. The HO-penta-CBs was themore » predominant homologue group, followed by HO-hexa-CBs and HO-hepta-CBs. No preferential pathway for the metabolism of HO-PCBs (HO-direct insertion or NIH-shift of a chlorine atom) could be evidenced. The concentrations of pentachlorophenol (PCP) in the serum of weaned NES increased from 103±7 pg/mL at early fast to 246±41 pg/mL at late fast, which is within the range of PCP concentrations usually encountered in marine mammals. - Highlights: • Σ HO-PCB concentrations in serum significantly increased between early and late fast. • The HO-penta-CBs were the predominant homologue group measured in serum. • No preferential pathway for the metabolism of HO-PCBs could be evidenced. • PCP concentrations in serum significantly increased between early and late fast.« less

Therapeutic effects of L-Cysteine in newborn mice subjected to hypoxia-ischemia brain injury via the CBS/H2S system: Role of oxidative stress and endoplasmic reticulum stress.

PubMed

Liu, Song; Xin, Danqing; Wang, Lingxiao; Zhang, Tiantian; Bai, Xuemei; Li, Tong; Xie, Yunkai; Xue, Hao; Bo, Shishi; Liu, Dexiang; Wang, Zhen

2017-10-01

Neonatal hypoxic-ischemic (HI) injury is a major cause of neonatal death and neurological dysfunction. H 2 S has been shown to protect against hypoxia-induced injury and apoptosis of neurons. L-Cysteine is catalyzed by cystathionine-β-synthase (CBS) in the brain and sequentially produces endogenous H 2 S. The present study was designed to investigate whether L-Cysteine could attenuate the acute brain injury and improve neurobehavioral outcomes following HI brain injury in neonatal mice by releasing endogenous H 2 S. L-Cysteine treatment significantly attenuated brain edema and decreased infarct volume and neuronal cell death, as shown by a decrease in the Bax/Bcl-2 ratio, suppression of caspase-3 activation, and reduced phosphorylation of Akt and ERK at 72h after HI. Additionally, L-Cysteine substantially up-regulated NF-E2-related factor 2 and heme oxygenase-1 expression. L-Cysteine also decreased endoplasmic reticulum (ER) stress-associated pro-apoptotic protein expression. Furthermore, L-Cysteine had long-term effects by protecting against the loss of ipsilateral brain tissue and improving neurobehavioral outcomes. Importantly, pre-treatment with a CBS inhibitor significantly attenuated the neuroprotection of L-Cysteine on HI insult. Thus, L-Cysteine exerts neuroprotection against HI-induced injury in neonates via the CBS/H 2 S pathway, mediated in part by anti-apoptotic effects and reduced oxidative stress and ER stress. Thus, L-Cysteine may be a promising treatment for HI. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Comparative genomics of citric-acid producing Aspergillus niger ATCC 1015 versus enzyme-producing CBS 513.88

DOE Office of Scientific and Technical Information (OSTI.GOV)

Andersen, Mikael R.; Salazar, Margarita; Schaap, Peter

2011-06-01

The filamentous fungus Aspergillus niger exhibits great diversity in its phenotype. It is found globally, both as marine and terrestrial strains, produces both organic acids and hydrolytic enzymes in high amounts, and some isolates exhibit pathogenicity. Although the genome of an industrial enzyme-producing A. niger strain (CBS 513.88) has already been sequenced, the versatility and diversity of this species compels additional exploration. We therefore undertook whole genome sequencing of the acidogenic A. niger wild type strain (ATCC 1015), and produced a genome sequence of very high quality. Only 15 gaps are present in the sequence and half the telomeric regionsmore » have been elucidated. Moreover, sequence information from ATCC 1015 was utilized to improve the genome sequence of CBS 513.88. Chromosome-level comparisons uncovered several genome rearrangements, deletions, a clear case of strain-specific horizontal gene transfer, and identification of 0.8 megabase of novel sequence. Single nucleotide polymorphisms per kilobase (SNPs/kb) between the two strains were found to be exceptionally high (average: 7.8, maximum: 160 SNPs/kb). High variation within the species was confirmed with exo-metabolite profiling and phylogenetics. Detailed lists of alleles were generated, and genotypic differences were observed to accumulate in metabolic pathways essential to acid production and protein synthesis. A transcriptome analysis revealed up-regulation of the electron transport chain, specifically the alternative oxidative pathway in ATCC 1015, while CBS 513.88 showed significant up regulation of genes associated with biosynthesis of amino acids that are abundant in glucoamylase A, tRNA-synthases and protein transporters.« less

A Multi-Region Magnetoimpedance-Based Bio-Analytical System for Ultrasensitive Simultaneous Determination of Cardiac Biomarkers Myoglobin and C-Reactive Protein.

PubMed

Yang, Zhen; Wang, Huanhuan; Guo, Pengfei; Ding, Yuanyuan; Lei, Chong; Luo, Yongsong

2018-06-01

Cardiac biomarkers (CBs) are substances that appear in the blood when the heart is damaged or stressed. Measurements of the level of CBs can be used in course of diagnostics or monitoring the state of the health of group risk persons. A multi-region bio-analytical system (MRBAS) based on magnetoimpedance (MI) changes was proposed for ultrasensitive simultaneous detection of CBs myoglobin (Mb) and C-reactive protein (CRP). The microfluidic device was designed and developed using standard microfabrication techniques for their usage in different regions, which were pre-modified with specific antibody for specified detection. Mb and CRP antigens labels attached to commercial Dynabeads with selected concentrations were trapped in different detection regions. The MI response of the triple sensitive element was carefully evaluated in initial state and in the presence of biomarkers. The results showed that the MI-based bio-sensing system had high selectivity and sensitivity for detection of CBs. Compared with the control region, ultrasensitive detections of CRP and Mb were accomplished with the detection limits of 1.0 pg/mL and 0.1 pg/mL, respectively. The linear detection range contained low concentration detection area and high concentration detection area, which were 1 pg/mL⁻10 ng/mL, 10⁻100 ng/mL for CRP, and 0.1 pg/mL⁻1 ng/mL, 1 n/mL⁻80 ng/mL for Mb. The measurement technique presented here provides a new methodology for multi-target biomolecules rapid testing.

Intrasteric control of AMPK via the gamma1 subunit AMP allosteric regulatory site.

PubMed

Adams, Julian; Chen, Zhi-Ping; Van Denderen, Bryce J W; Morton, Craig J; Parker, Michael W; Witters, Lee A; Stapleton, David; Kemp, Bruce E

2004-01-01

AMP-activated protein kinase (AMPK) is a alphabetagamma heterotrimer that is activated in response to both hormones and intracellular metabolic stress signals. AMPK is regulated by phosphorylation on the alpha subunit and by AMP allosteric control previously thought to be mediated by both alpha and gamma subunits. Here we present evidence that adjacent gamma subunit pairs of CBS repeat sequences (after Cystathionine Beta Synthase) form an AMP binding site related to, but distinct from the classical AMP binding site in phosphorylase, that can also bind ATP. The AMP binding site of the gamma(1) CBS1/CBS2 pair, modeled on the structures of the CBS sequences present in the inosine monophosphate dehydrogenase crystal structure, contains three arginine residues 70, 152, and 171 and His151. The yeast gamma homolog, snf4 contains a His151Gly substitution, and when this is introduced into gamma(1), AMP allosteric control is substantially lost and explains why the yeast snf1p/snf4p complex is insensitive to AMP. Arg70 in gamma(1) corresponds to the site of mutation in human gamma(2) and pig gamma(3) genes previously identified to cause an unusual cardiac phenotype and glycogen storage disease, respectively. Mutation of any of AMP binding site Arg residues to Gln substantially abolishes AMP allosteric control in expressed AMPK holoenzyme. The Arg/Gln mutations also suppress the previously described inhibitory properties of ATP and render the enzyme constitutively active. We propose that ATP acts as an intrasteric inhibitor by bridging the alpha and gamma subunits and that AMP functions to derepress AMPK activity.

Endogenous S-sulfhydration of PTEN helps protect against modification by nitric oxide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ohno, Kazuki; Okuda, Kosaku; Uehara, Takashi, E-mail: uehara@pharm.okayama-u.ac.jp

2015-01-02

Highlights: • PTEN is S-sulfhydrated endogenously in SH-SY5Y human neuroblastoma cells. • Preventing this modification by knocking down CBS renders PTEN sensitive to NO. • pAkt levels are increased significantly in CBS siRNA-transfected cells. • H{sub 2}S functions as an endogenous regulator of PTEN in neuronal cells. - Abstract: Hydrogen sulfide (H{sub 2}S) is a gaseous regulatory factor produced by several enzymes, and plays a pivotal role in processes such as proliferation or vasodilation. Recent reports demonstrated the physiological and pathophysiological functions of H{sub 2}S in neurons. PTEN is a target of nitric oxide (NO) or hydrogen peroxide, and themore » oxidative modification of cysteine (Cys) residue(s) attenuates its enzymatic activity. In the present study, we assessed the effect of H{sub 2}S on the direct modification of PTEN and the resulting downstream signaling. A modified biotin switch assay in SH-SY5Y human neuroblastoma cells revealed that PTEN is S-sulfhydrated endogenously. Subsequently, site-directed mutagenesis demonstrated that both Cys71 and Cys124 in PTEN are targets for S-sulfhydration. Further, the knockdown of cystathionine β-synthetase (CBS) using siRNA decreased this modification in a manner that was correlated to amount of H{sub 2}S. PTEN was more sensitive to NO under these conditions. These results suggest that the endogenous S-sulfhydration of PTEN via CBS/H{sub 2}S plays a role in preventing the S-nitrosylation that would inhibition its enzymatic activity under physiological conditions.« less

Adult classical homocystinuria requiring parenteral nutrition: Pitfalls and management.

PubMed

Tran, Christel; Bonafé, Luisa; Nuoffer, Jean-Marc; Rieger, Julie; Berger, Mette M

2017-07-25

Homocystinuria due to cystathionine beta synthase (CBS) deficiency presents with a wide clinical spectrum. Treatment by the enteral route aims at reducing homocysteine levels by using vitamin B6, possibly methionine-restricted diet, betaine and/or folate and vitamin B 12 supplementation. Currently no nutritional guidelines exist regarding parenteral nutrition (PN) under acute conditions. Exhaustive literature search was performed, in order to identify the relevant studies describing the pathogenesis and nutritional intervention of adult classical homocystinuria requiring PN. Description of an illustrative case of an adult female with CBS deficiency and intestinal perforation, who required total PN due to contraindication to enteral nutrition. Nutritional management of decompensated classical homocystinuria is complex and currently no recommendation exists regarding PN composition. Amino acid profile and monitoring of total homocysteine concentration are the main tools enabling a precise assessment of the severity of metabolic alterations. In case of contraindication to enteral nutrition, compounded PN will be required, as described in this paper, to ensure adequate low amounts of methionine and others essential amino acids and avoid potentially fatal toxic hypermethioninemia. By reviewing the literature and reporting successful nutritional management of a decompensated CBS deficiency using tailored PN with limited methionine intake and n-3 PUFA addition, we would like to underscore the fact that standard PN solutions are not adapted for CBS deficient critical ill patients: new solutions are required. High methionine levels (>800 μmol/L) being potentially neurotoxic, there is an urgent need to improve our knowledge of acute nutritional therapy. Copyright © 2017 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

Candida chanthaburiensis sp. nov., Candida kungkrabaensis sp. nov. and Candida suratensis sp. nov., three novel yeast species from decaying plant materials submerged in water of mangrove forests.

PubMed

Limtong, Savitree; Yongmanitchai, Wichien

2010-10-01

In a taxonomic study of yeasts isolated from decaying plant materials submerged in water of mangrove forests in Thailand, three strains isolated from tree bark (EM33(T)), a fallen leaf (EM40(T)) and a detached branch (SM56(T)) were found to represent three novel yeast species. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, the sequence analysis of the D1/D2 domain of the large subunit (LSU) rRNA gene, and the phylogenetic analysis, the three strains were assigned as three novel Candida species. They were named as Candida chanthaburiensis sp. nov. (type strain EM33(T) = BCC 23057(T) = NBRC 102176(T) = CBS 10926(T)), Candida kungkrabaensis sp. nov. (type strain EM40(T) = BCC 23060(T) = NBRC 102179(T) = CBS 10927(T)), and Candida suratensis sp. nov. (type strain SM56(T) = BCC 25961(T) = NBRC 103858(T) = CBS 10928(T)).

CBP-mediated SMN acetylation modulates Cajal body biogenesis and the cytoplasmic targeting of SMN.

PubMed

Lafarga, Vanesa; Tapia, Olga; Sharma, Sahil; Bengoechea, Rocio; Stoecklin, Georg; Lafarga, Miguel; Berciano, Maria T

2018-02-01

The survival of motor neuron (SMN) protein plays an essential role in the biogenesis of spliceosomal snRNPs and the molecular assembly of Cajal bodies (CBs). Deletion of or mutations in the SMN1 gene cause spinal muscular atrophy (SMA) with degeneration and loss of motor neurons. Reduced SMN levels in SMA lead to deficient snRNP biogenesis with consequent splicing pathology. Here, we demonstrate that SMN is a novel and specific target of the acetyltransferase CBP (CREB-binding protein). Furthermore, we identify lysine (K) 119 as the main acetylation site in SMN. Importantly, SMN acetylation enhances its cytoplasmic localization, causes depletion of CBs, and reduces the accumulation of snRNPs in nuclear speckles. In contrast, the acetylation-deficient SMNK119R mutant promotes formation of CBs and a novel category of promyelocytic leukemia (PML) bodies enriched in this protein. Acetylation increases the half-life of SMN protein, reduces its cytoplasmic diffusion rate and modifies its interactome. Hence, SMN acetylation leads to its dysfunction, which explains the ineffectiveness of HDAC (histone deacetylases) inhibitors in SMA therapy despite their potential to increase SMN levels.

Acylethanolamides and endocannabinoid signaling system in dorsal striatum of rats exposed to perinatal asphyxia.

PubMed

Holubiec, Mariana I; Romero, Juan I; Blanco, Eduardo; Tornatore, Tamara Logica; Suarez, Juan; Rodríguez de Fonseca, Fernando; Galeano, Pablo; Capani, Francisco

2017-07-13

Endocannabinoids (eCBs) and acylethanolamides (AEs) have lately received more attention due to their neuroprotective functions in neurological disorders. Here we analyze the alterations induced by perinatal asphyxia (PA) in the main metabolic enzymes and receptors of the eCBs/AEs in the dorsal striatum of rats. To induce PA, we used a model developed by Bjelke et al. (1991). Immunohistochemical techniques were carried out to determine the expression of neuronal and glial markers (NeuN and GFAP), eCBs/AEs synthesis and degradation enzymes (DAGLα, NAPE-PLD and FAAH) and their receptors (CB1 and PPARα). We found a decrease in NAPE-PLD and PPARα expression. Since NAPE-PLD and PPARα take part in the production and reception of biochemical actions of AEs, such as oleoylethanolamide, these results may suggest that PA plays a key role in the regulation of this system. These data agree with previous results obtained in the hippocampus and encourage us to develop further studies using AEs as potential neuroprotective compounds. Copyright © 2017 Elsevier B.V. All rights reserved.

Increased hydrophobicity in Malassezia species correlates with increased proinflammatory cytokine expression in human keratinocytes.

PubMed

Akaza, Narifumi; Akamatsu, Hirohiko; Takeoka, Shiori; Mizutani, Hiroshi; Nakata, Satoru; Matsunaga, Kayoko

2012-11-01

Malassezia cells stimulate cytokine production by keratinocytes, although this ability differs among Malassezia species for unknown reasons. The aim of this study was to clarify the factors determining the ability to induce cytokine production by human keratinocytes in response to Malassezia species. M. furfur NBRC 0656, M. sympodialis CBS 7222, M. dermatis JCM 11348, M. globosa CBS 7966, M. restricta CBS 7877, and three strains each of M. globosa, M. restricta, M. dermatis, M. sympodialis, and M. furfur maintained under various culture conditions were used. Normal human epidermal keratinocytes (NHEKs) (1 × 10(5) cells) and the Malassezia species (1 × 10(6) cells) were co-cultured, and IL-1α, IL-6, and IL-8 mRNA levels were determined. Moreover, the hydrophobicity and β-1,3-glucan expression at the surface of Malassezia cells were analyzed. The ability of Malassezia cells to trigger the mRNA expression of proinflammatory cytokines in NHEKs differed with the species and conditions and was dependent upon the hydrophobicity of Malassezia cells not β-1,3-glucan expression.

Women and cosmetic breast surgery: weighing the medical, social, and lifestyle risks.

PubMed

Boulton, Tiffany N; Malacrida, Claudia

2012-04-01

In this article we provide a comparative analysis of qualitative, semistructured interviews with 24 women who had undergone different forms of cosmetic breast surgery (CBS). We argue that women must negotiate three types of risk: potential medical risks, lifestyle risks connected with choosing "frivolous" self-enhancements, and countervailing social risks affiliated with pressures to maximize one's feminine beauty. In addition, we highlight the challenges faced in negotiating these risks by examining the limits to traditional forms of medical informed consent provided to the women, who received little information on the medical risks associated with CBS, or who were given uncertain and contradictory risk information. Even respondents who felt that they were well informed expressed difficulties in making "wise" choices because the risks were distant or unlikely, and hence easily minimized. Given this, it is fairly understandable that the known social risks of "failed" beauty faced by the women often outweighed the ambiguous or understated risks outlined by medicine. We argue that traditional notions of informed consent and risk awareness might not be adequate for women choosing CBS.

Investigation of saponification for determination of polychlorinated biphenyls in marine sediments.

PubMed

Numata, Masahiko; Yarita, Takashi; Aoyagi, Yoshie; Yamazaki, Misako; Takatsu, Akiko

2005-02-01

The effects of saponification conditions (temperature and water content of saponifying solution) on the determination of chlorinated biphenyls (CBs) in marine sediments were investigated. Although highly chlorinated biphenyls (nona- to deca-CBs) decomposed during high-temperature saponification, the degree of degradation was reduced by adding water to the ethanolic potassium hydroxide saponifying solution. Room-temperature saponification yielded quantitative recovery of highly chlorinated biphenyl surrogates but low extraction efficiencies of lightly chlorinated biphenyls (mono- to di-CBs). The same samples were analyzed by other extraction techniques, for example, pressurized liquid extraction, and analytical results were compared. The mono- and di-CB concentrations were correlated with the extraction temperatures of various extraction techniques. In particular, the concentrations of some CB congeners (CB11, CB14) were higher with saponification. The low degree of degradation of highly chlorinated biphenyls and the high recovery of lightly chlorinated biphenyls were compatible when room-temperature and high-temperature saponification were combined. Except for the anomalies of CB11 and CB14, the combined method gave satisfactory results for analysis of PCBs.

Galactose utilization sheds new light on sugar metabolism in the sequenced strain Dekkera bruxellensis CBS 2499.

PubMed

Moktaduzzaman, Md; Galafassi, Silvia; Capusoni, Claudia; Vigentini, Ileana; Ling, Zhihao; Piškur, Jure; Compagno, Concetta

2015-03-01

Dekkera bruxellensis and Saccharomyces cerevisiae are considered two phylogenetically distant relatives, but they share several industrial relevant traits such as the ability to produce ethanol under aerobic conditions (Crabtree effect), high tolerance towards ethanol and acids, and ability to grow without oxygen. Beside a huge adaptability, D. bruxellensis exhibits a broader spectrum in utilization of carbon and nitrogen sources in comparison to S. cerevisiae. With the aim to better characterize its carbon source metabolism and regulation, the usage of galactose and the role that glucose plays on sugar metabolism were investigated in D. bruxellensis CBS 2499. The results indicate that in this yeast galactose is a non-fermentable carbon source, in contrast to S. cerevisiae that can ferment it. In particular, its metabolism is affected by the nitrogen source. Interestingly, D. bruxellensis CBS 2499 exhibits the 'short-term Crabtree effect', and the expression of genes involved in galactose utilization and in respiratory metabolism is repressed by glucose, similarly to what occurs in S. cerevisiae. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permission@oup.com.

Application of Fracture Mechanics to Specify the Proof Load Factor for Clamp Band Systems of Launch Vehicles

NASA Astrophysics Data System (ADS)

Singaravelu, J.; Sundaresan, S.; Nageswara Rao, B.

2013-04-01

This article presents a methodology for evaluation of the proof load factor (PLF) for clamp band system (CBS) made of M250 Maraging steel following fracture mechanics principles.CBS is most widely used as a structural element and as a separation system. Using Taguchi's design of experiments and the response surface method (RSM) the compact tension specimens were tested to establish an empirical relation for the failure load ( P max) in terms of the ultimate strength, width, thickness, and initial crack length. The test results of P max closely matched with the developed RSM empirical relation. Crack growth rates of the maraging steel in different environments were examined. Fracture strength (σf) of center surface cracks and through-crack tension specimens are evaluated utilizing the fracture toughness ( K IC). Stress induced in merman band at flight loading conditions is evaluated to estimate the higher load factor and PLF. Statistical safety factor and reliability assessments were made for the specified flaw sizes useful in the development of fracture control plan for CBS of launch vehicles.

Breaking the bottleneck: Use of molecular tailoring approach for the estimation of binding energies at MP2/CBS limit for large water clusters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Singh, Gurmeet; Nandi, Apurba; Gadre, Shridhar R., E-mail: gadre@iitk.ac.in

2016-03-14

A pragmatic method based on the molecular tailoring approach (MTA) for estimating the complete basis set (CBS) limit at Møller-Plesset second order perturbation (MP2) theory accurately for large molecular clusters with limited computational resources is developed. It is applied to water clusters, (H{sub 2}O){sub n} (n = 7, 8, 10, 16, 17, and 25) optimized employing aug-cc-pVDZ (aVDZ) basis-set. Binding energies (BEs) of these clusters are estimated at the MP2/aug-cc-pVNZ (aVNZ) [N = T, Q, and 5 (whenever possible)] levels of theory employing grafted MTA (GMTA) methodology and are found to lie within 0.2 kcal/mol of the corresponding full calculationmore » MP2 BE, wherever available. The results are extrapolated to CBS limit using a three point formula. The GMTA-MP2 calculations are feasible on off-the-shelf hardware and show around 50%–65% saving of computational time. The methodology has a potential for application to molecular clusters containing ∼100 atoms.« less

Preparation and characterization of poly(methyl methacrylate) and poly(maleic anhydride-co-diallyl phthalate) grafted carbon black through γ-ray irradiation

NASA Astrophysics Data System (ADS)

Bo, Yang; Cui, Jiayang; Cai, Yangben; Xu, Shiai

2016-02-01

In this study, the grafting polymerization of methyl methacrylate (MMA) monomer and maleic anhydride/diallyl phthalate (MAH/DAP) co-monomer onto the surface of carbon black (CB) were carried out at room temperature and normal pressure by γ-ray irradiation. The surface chemistry of grafted CBs were characterized by infrared spectroscopy (IR), thermo-gravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS). The results show that there are some remanent polymers on the surface of modified CBs after extract for 48 h, indicating that poly(methyl methacrylate) (PMMA) and poly(MAH-co-DAP) have been successfully grafted onto the surface of CB without using initiator due to the high energy of γ-ray irradiation. Dynamic light scattering (DLS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) reveal that the grafted CBs have smaller average aggregate size and better dispersibility than that of CB in absolute ethanol. In addition, it was found that the amount of oxygen groups and the irradiation doses/dose rates have little effect on the grafting degree of CB.

The therapeutic potential of targeting the peripheral endocannabinoid/CB1 receptor system.

PubMed

Tam, Joseph; Hinden, Liad; Drori, Adi; Udi, Shiran; Azar, Shahar; Baraghithy, Saja

2018-03-01

Endocannabinoids (eCBs) are internal lipid mediators recognized by the cannabinoid-1 and -2 receptors (CB 1 R and CB 2 R, respectively), which also mediate the different physiological effects of marijuana. The endocannabinoid system, consisting of eCBs, their receptors, and the enzymes involved in their biosynthesis and degradation, is present in a vast number of peripheral organs. In this review we describe the role of the eCB/CB 1 R system in modulating the metabolism in several peripheral organs. We assess how eCBs, via activating the CB 1 R, contribute to obesity and regulate food intake. In addition, we describe their roles in modulating liver and kidney functions, as well as bone remodeling and mass. Special importance is given to emphasizing the efficacy of the recently developed peripherally restricted CB 1 R antagonists, which were pre-clinically tested in the management of energy homeostasis, and in ameliorating both obesity- and diabetes-induced metabolic complications. Copyright © 2018 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

The IASI cold box subsystem (CBS) a passive cryocooler for cryogenic detectors and optics

NASA Astrophysics Data System (ADS)

Bailly, B.; Courteau, P.; Maciaszek, T.

2017-11-01

In space, cooling down Infra Red detectors and optics to cryogenic temperature raises always the same issue : what is the best way to manage simultaneously thermal cooling, stability, mechanical discoupling and accurate focal plane components location, in a lightweight and compact solution? The passive cryocooler developed by Alcatel SPace Industries under CNES contract in the frame of the IASI instrument (Infrared Atmospheric Sounding Interferometer), offers an efficient solution for 90K to 100K temperature levels. We intend you to present the architecture and performance validation plan of the CBS.

Military Personnel Dilemmas: Perspectives on Gender-Related Issues. A selected List of Resource Materials Prepared for the Human Resources Division, HQ FORSCOM

DTIC Science & Technology

1983-08-01

interfered with his performance of his duties. " "- "Army Discharges’ Woman After Marriage to Alleged Transsexual ." CBS NEWS (MORNING NEWS). July 23...1977. p. 11. A WAC is discharged because of her marriage to a former WAC who now claims to be a transsexual man. The Army says that there may have been...a . .- psycholoqical transition but not a physical one. "Army Seeks Dismissal of Woman Married to Transsexual ." CBS NEWS (MORNING NEWS). June 6, 1977

High-level ab initio predictions for the ionization energy, electron affinity, and heats of formation of cyclopentadienyl radical, cation, and anion, C5H5/C5H5+/C5H5-.

PubMed

Lo, Po-Kam; Lau, Kai-Chung

2014-04-03

The ionization energy (IE), electron affinity (EA), and heats of formation (ΔH°f0/ΔH°f298) for cyclopentadienyl radical, cation, and anion, C5H5/C5H5(+)/C5H5(-), have been calculated by wave function-based ab initio CCSDT/CBS approach, which involves approximation to complete basis set (CBS) limit at coupled-cluster level with up to full triple excitations (CCSDT). The zero-point vibrational energy correction, core-valence electronic correction, scalar relativistic effect, and higher-order corrections beyond the CCSD(T) wave function are included in these calculations. The allylic [C5H5((2)A2)] and dienylic [C5H5((2)B1)] forms of cyclopentadienyl radical are considered: the ground state structure exists in the dienyl form and it is about 30 meV more stable than the allylic structure. Both structures are lying closely and are interconvertible along the normal mode of b2 in-plane vibration. The CCSDT/CBS predictions (in eV) for IE[C5H5(+)((3)A1')←C5H5((2)B1)] = 8.443, IE[C5H5(+)((1)A1)←C5H5((2)B1)] = 8.634 and EA[C5H5(-)((1)A1')←C5H5((2)B1)] = 1.785 are consistent with the respective experimental values of 8.4268 ± 0.0005, 8.6170 ± 0.0005, and 1.808 ± 0.006, obtained from photoelectron spectroscopic measurements. The ΔH°f0/ΔH°f298's (in kJ/mol) for C5H5/C5H5(+)/C5H5(-) have also been predicted by the CCSDT/CBS method: ΔH°f0/ΔH°f298[C5H5((2)B1)] = 283.6/272.0, ΔH°f0/ΔH°f298[C5H5(+)((3)A1')] = 1098.2/1086.9, ΔH°f0/ΔH°f298[C5H5(+)((1)A1)] = 1116.6/1106.0, and ΔH°f0/ΔH°f298[C5H5(-)((1)A1')] = 111.4/100.0. The comparisons between the CCSDT/CBS predictions and the experimental values suggest that the CCSDT/CBS procedure is capable of predicting reliable IE(C5H5)'s and EA(C5H5) with uncertainties of ± 17 and ± 23 meV, respectively.

On the validity of the basis set superposition error and complete basis set limit extrapolations for the binding energy of the formic acid dimer

NASA Astrophysics Data System (ADS)

Miliordos, Evangelos; Xantheas, Sotiris S.

2015-03-01

We report the variation of the binding energy of the Formic Acid Dimer with the size of the basis set at the Coupled Cluster with iterative Singles, Doubles and perturbatively connected Triple replacements [CCSD(T)] level of theory, estimate the Complete Basis Set (CBS) limit, and examine the validity of the Basis Set Superposition Error (BSSE)-correction for this quantity that was previously challenged by Kalescky, Kraka, and Cremer (KKC) [J. Chem. Phys. 140, 084315 (2014)]. Our results indicate that the BSSE correction, including terms that account for the substantial geometry change of the monomers due to the formation of two strong hydrogen bonds in the dimer, is indeed valid for obtaining accurate estimates for the binding energy of this system as it exhibits the expected decrease with increasing basis set size. We attribute the discrepancy between our current results and those of KKC to their use of a valence basis set in conjunction with the correlation of all electrons (i.e., including the 1s of C and O). We further show that the use of a core-valence set in conjunction with all electron correlation converges faster to the CBS limit as the BSSE correction is less than half than the valence electron/valence basis set case. The uncorrected and BSSE-corrected binding energies were found to produce the same (within 0.1 kcal/mol) CBS limits. We obtain CCSD(T)/CBS best estimates for De = - 16.1 ± 0.1 kcal/mol and for D0 = - 14.3 ± 0.1 kcal/mol, the later in excellent agreement with the experimental value of -14.22 ± 0.12 kcal/mol.

Two new anamorphic yeasts species, Cyberlindnera samutprakarnensis sp. nov. and Candida thasaenensis sp. nov., isolated from industrial wastes in Thailand.

PubMed

Poomtien, Jamroonsri; Jindamorakot, Sasitorn; Limtong, Savitree; Pinphanichakarn, Pairoh; Thaniyavarn, Jiraporn

2013-01-01

Three yeast strains were isolated from industrial wastes in Thailand. Based on the phylogenetic sequence analysis of the D1/D2 region of the large subunit rRNA gene, the internal transcribed spacer (ITS1-5.8S rRNA gene-ITS2; ITS1-2) region, and their physiological characteristics, the three strains were found to represent two novel species of the ascomycetous anamorphic yeast. Strain JP52(T) represent a novel species which was named Cyberlindnera samutprakarnensis sp. nov. (type strain JP52(T); = BCC 46825(T) = JCM 17816(T) = CBS 12528(T), MycoBank no. MB800879), which was differentiated from the closely related species Cyberlindnera mengyuniae CBS 10845(T) by 2.9 % sequence divergence in the D1/D2 region and 4.4 % sequence divergence in the ITS1-2. Strain JP59(T) and JP60 were identical in their D1/D2 and ITS1-2 regions, which were closely related to those of Scheffersomyces spartinae CBS 6059(T) by 0.9 and 1.0 % sequence divergence, respectively. In addition, supportive evidence of actin gene and translational elongation factor gene by sequence divergence of 6.5 % each confirmed their distinct status. Furthermore, JP59(T) and JP60 differentiated from the closely related species in some biochemical and physiological characteristics. These two strains were assigned as a single novel species which was named Candida thasaenensis sp. nov. (type JP59(T) = BCC 46828(T) = JCM 17817(T) = CBS 12529(T), MycoBank no. MB800880).

The association between the 844ins68 polymorphism in the CBS gene and breast cancer

PubMed Central

Figuera-Villanueva, Luis Eduardo; Ramos-Silva, Adriana; Salas-González, Efraín; Puebla-Pérez, Ana María; Peralta-Leal, Valeria; García-Ortiz, José Elías; Dávalos-Rodríguez, Ingrid Patricia; Zúñiga-González, Guillermo Moisés

2014-01-01

Introduction The cystathionine beta synthase (CBS) gene plays an important role in homocysteine metabolism because it catalyzes the first step of the transsulfuration pathway, during which homocysteine is converted to cystathionine. Polymorphisms of CBS have been associated with cancer. Material and methods We examined the role of the 844ins68 polymorphism by comparing the genotypes of 371 healthy Mexican women with the genotypes of 323 Mexican women with breast cancer (BC). Results The observed genotype frequencies for controls and BC patients were 1% and 2% for Ins/Ins, 13% and 26% for W/Ins, and 86% and 72% for W/W, respectively. We found that the odds ratio (OR) was 2.2, with a 95% confidence interval (95% CI) of 1.5–3.3, p = 0.0001. The association was also evident when comparing the distribution of the W/Ins-Ins/Ins genotypes in patients in the following categories: 1) menopause and high γ-glutamyltransferase (GGT) levels (OR of 2.17, 95% CI: 1.17–4.26, p = 0.02), 2) chemotherapy response and high lactate dehydrogenase (LDH) levels (OR 2.2, 95% CI: 1.08–4.4, p = 0.027), 3) chemotherapy response and high GGT levels (OR 2.46, 95% CI: 1.2–4.8, p = 0.007), and 4) body mass index (BMI) and III–IV tumor stage (OR 3.2, 95% CI: 1.2–8.3, p = 0.013). Conclusions We conclude that the genotypes W/Ins-Ins/Ins of the 844ins68 polymorphism in the CBS gene contribute significantly to BC susceptibility in the analyzed sample from the Mexican population. PMID:25624861

Comparative genomics of citric-acid-producing Aspergillus niger ATCC 1015 versus enzyme-producing CBS 513.88

PubMed Central

Andersen, Mikael R.; Salazar, Margarita P.; Schaap, Peter J.; van de Vondervoort, Peter J.I.; Culley, David; Thykaer, Jette; Frisvad, Jens C.; Nielsen, Kristian F.; Albang, Richard; Albermann, Kaj; Berka, Randy M.; Braus, Gerhard H.; Braus-Stromeyer, Susanna A.; Corrochano, Luis M.; Dai, Ziyu; van Dijck, Piet W.M.; Hofmann, Gerald; Lasure, Linda L.; Magnuson, Jon K.; Menke, Hildegard; Meijer, Martin; Meijer, Susan L.; Nielsen, Jakob B.; Nielsen, Michael L.; van Ooyen, Albert J.J.; Pel, Herman J.; Poulsen, Lars; Samson, Rob A.; Stam, Hein; Tsang, Adrian; van den Brink, Johannes M.; Atkins, Alex; Aerts, Andrea; Shapiro, Harris; Pangilinan, Jasmyn; Salamov, Asaf; Lou, Yigong; Lindquist, Erika; Lucas, Susan; Grimwood, Jane; Grigoriev, Igor V.; Kubicek, Christian P.; Martinez, Diego; van Peij, Noël N.M.E.; Roubos, Johannes A.; Nielsen, Jens; Baker, Scott E.

2011-01-01

The filamentous fungus Aspergillus niger exhibits great diversity in its phenotype. It is found globally, both as marine and terrestrial strains, produces both organic acids and hydrolytic enzymes in high amounts, and some isolates exhibit pathogenicity. Although the genome of an industrial enzyme-producing A. niger strain (CBS 513.88) has already been sequenced, the versatility and diversity of this species compel additional exploration. We therefore undertook whole-genome sequencing of the acidogenic A. niger wild-type strain (ATCC 1015) and produced a genome sequence of very high quality. Only 15 gaps are present in the sequence, and half the telomeric regions have been elucidated. Moreover, sequence information from ATCC 1015 was used to improve the genome sequence of CBS 513.88. Chromosome-level comparisons uncovered several genome rearrangements, deletions, a clear case of strain-specific horizontal gene transfer, and identification of 0.8 Mb of novel sequence. Single nucleotide polymorphisms per kilobase (SNPs/kb) between the two strains were found to be exceptionally high (average: 7.8, maximum: 160 SNPs/kb). High variation within the species was confirmed with exo-metabolite profiling and phylogenetics. Detailed lists of alleles were generated, and genotypic differences were observed to accumulate in metabolic pathways essential to acid production and protein synthesis. A transcriptome analysis supported up-regulation of genes associated with biosynthesis of amino acids that are abundant in glucoamylase A, tRNA-synthases, and protein transporters in the protein producing CBS 513.88 strain. Our results and data sets from this integrative systems biology analysis resulted in a snapshot of fungal evolution and will support further optimization of cell factories based on filamentous fungi. PMID:21543515

Hypokalemic paralysis in a middle-aged female with classic Bartter syndrome.

PubMed

Chiang, Wen-Fang; Lin, Shih-Hung; Chan, Jenq-Shyong; Lin, Shih-Hua

2014-02-01

Inherited classic Bartter syndrome (cBS) is an autosomal recessive renal tubular disorder resulting from inactivating mutations in the asolateral chloride channel (C1C-Kb) and usually presents in early infancy or childhood with mild to moderate hypokalemia. Profound hypokalemic paralysis in patients with cBS is extremely rare, especially in middle age. A 45-year-old Chinese female patient was referred for evaluation of chronic severe hypokalemia despite regular K+ supplementation (1 mmol/kg/d). She had had two episodes of muscle paralysis due to severe hypokalemia (K+ 1.9 - 2.1 mmol/l) in the past 3 years. She denied vomiting, diarrhea, or the use of laxatives or diuretics. Her blood pressure was normal. Biochemical studies showed hypokalemia (K+ 2.5 mmol/l) with renal potassium wasting, metabolic alkalosis (HCO3- 32 mmol/l), normomagnesemia (Mg2+ 0.8 mmol/l), hypercalciuria (calcium to creatinine ratio 0.5 mmol/mmol; normal < 0.22 mmol/mol), high plasma renin activity, but normal plasma aldosterone concentration. Abdominal sonography revealed neither renal stones nor nephrocalcinosis. Acquired causes of cBS such as autoimmune disease and drugs were all excluded. Molecular analysis of the CLCNKB gene, encoding ClC-Kb, and SLC12A3, encoding the thiazide-sensitive sodium chloride cotransporter (NCC), revealed compound heterozygous mutations in CLCNKB (L335P and G470E) inherited from her parents; her SLC12A3 was normal. These two mutations were not identified in 100 healthy subjects. Her plasma K+ concentration rose to 3 - 3.5 mmol/l after the addition of spironolactone. Inherited cBS may present with hypokalemic paralysis and should be considered in adult patients with hypokalemia and metabolic alkalosis.

Physiologic Levels of Endogenous Hydrogen Sulfide Maintain the Proliferation and Differentiation Capacity of Periodontal Ligament Stem Cells.

PubMed

Su, Yingying; Liu, Dayong; Liu, Yi; Zhang, Chunmei; Wang, Jinsong; Wang, Songlin

2015-11-01

Many invading oral bacteria are known to produce considerable amounts of hydrogen sulfide (H2S). The toxic activity of exogenous H2S in periodontal tissue has been demonstrated, but the role of endogenous H2S in the physiologic function of periodontal tissue remains poorly understood. The purpose of the present study is to investigate the biologic functions of H2S in the proliferation and differentiation of human periodontal ligament stem cells (PDLSCs). PDLSCs were isolated from periodontal ligament tissues of periodontally healthy volunteers or patients with periodontitis. Immunocytochemical staining, flow cytometry, and Western blot analysis were used to examine the expression of H2S-synthesizing enzymes cystathionine-β-synthase (CBS) and cystathionine-γ-lyase (CSE). The proliferation capacity of PDLSCs was determined by cell counting kit-8 assay, carboxyfluorescein succinimidyl ester analysis, and 5-ethynyl-2'-deoxyuridine assay. The osteogenic potential of PDLSCs was tested using alkaline phosphatase staining, Alizarin Red staining, and in vivo transplantation experiments. Oil Red O staining was used to analyze adipogenic ability. The results show that human PDLSCs express both CBS and CSE and produce H2S. Blocking the generation of endogenous H2S with CBS inhibitor hydroxylamine significantly attenuated PDLSC proliferation and reduced the osteogenic and adipogenic differentiation capacity of PDLSCs. In contrast, CSE inhibitor DL-propargylglycine had no effect on PDLSC function. Exogenous H2S could inhibit the production of endogenous H2S and impair PDLSC function in a dose-dependent manner. Physiologic levels of endogenous H2S maintain the proliferation and differentiation capacity of PDLSCs, and CBS may be the main source of endogenous H2S in PDLSCs.

Hyperhomocysteinemia in polycystic ovary syndrome: decreased betaine-homocysteine methyltransferase and cystathionine β-synthase-mediated homocysteine metabolism.

PubMed

Li, Da; Liu, Hong-Xiang; Fang, Yuan-Yuan; Huo, Jia-Ning; Wu, Qi-Jun; Wang, Tian-Ren; Zhou, Yi-Ming; Wang, Xiu-Xia; Ma, Xiao-Xin

2018-05-22

What are the metabolic characteristics of homocysteine in polycystic ovary syndrome (PCOS)? Homocysteine concentrations were determined in serum samples from non-obese and obese control subjects and PCOS patients. Homocysteine metabolism was studied in a rat model of PCOS established using dehydroepiandrosterone (DHEA) or DHEA in combination with a high-fat diet (HFD). It was shown that (i) serum homocysteine concentrations were greater in PCOS patients than in control subjects in the obese group (P < 0.05) and serum homocysteine concentrations were significantly higher in the obese group than in the non-obese group, regardless of PCOS status (both P < 0.05); (ii) serum homocysteine concentrations were significantly increased in DHEA + HFD-induced rats compared with controls (P < 0.05); (iii) when compared with the control group, mRNA concentrations of homocysteine metabolic enzymes Bhmt and Cbs were significantly reduced in the liver tissues of DHEA + HFD-induced rats (both P < 0.0001); (iv) when compared with the control group, there was a significant decrease in the methylation concentrations of the Cbs (P < 0.05) and Bhmt (P < 0.05 and P < 0.0001) promoter in the DHEA + HFD group. The methylation patterns, together with previous data, indicate that hypomethylated promoter-mediated transcriptional activation of Bhmt and Cbs might be a defence mechanism against PCOS-related hyperhomocysteinemia. These findings indicate that decreased liver Bhmt and Cbs-mediated homocysteine metabolism might have a role in hyperhomocysteinemia in PCOS and provides further evidence for a potential role of decreased liver function in PCOS. Copyright © 2018 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

Candida alocasiicola sp. nov., Candida hainanensis sp. nov., Candida heveicola sp. nov. and Candida musiphila sp. nov., novel anamorphic, ascomycetous yeast species isolated from plants.

PubMed

Wang, Shi-An; Jia, Jian-Hua; Bai, Feng-Yan

2008-08-01

In a taxonomic study on the ascomycetous yeasts isolated from plant materials collected in tropical forests in Yunnan and Hainan Provinces, southern China, four strains isolated from tree sap (YJ2E(T)) and flowers (YF9E(T), YWZH3C(T) and YYF2A(T)) were revealed to represent four undescribed yeast species. Molecular phylogenetic analysis based on the large subunit (26S) rRNA gene D1/D2 domain sequences showed that strain YJ2E(T) was located in a clade together with Candida haemulonii and C. pseudohaemulonii. Strain YF9E(T) was most closely related to C. azyma and strain YWZH3C(T) to C. sorbophila and C. spandovensis. Strain YYF2A(T) was clustered in a clade containing small-spored Metschnikowia species and related anamorphic Candida species. The new strains differed from their closely related described species by more than 10% mismatches in the D1/D2 domain. No sexual states were observed for the four strains on various sporulation media. The new species are therefore assigned to the genus Candida and described as Candida alocasiicola sp. nov. (type strain, YF9E(T) = AS 2.3484(T) = CBS 10702(T)), Candida hainanensis sp. nov. (type strain, YYF2A(T) = AS 2.3478(T) = CBS 10696(T)), Candida heveicola sp. nov. (type strain, YJ2E(T) = AS 2.3483(T) = CBS 10701(T)) and Candida musiphila sp. nov. (type strain, YWZH3C(T) = AS 2.3479(T) = CBS 10697(T)).

RehAtt - scanning training for neglect enhanced by multi-sensory stimulation in Virtual Reality.

PubMed

Fordell, Helena; Bodin, Kenneth; Eklund, Anders; Malm, Jan

2016-06-01

There is a lack of effective treatment for neglect. We have developed a new training method, RehAtt™. The objective of this study was to determine whether RehAtt™ improves spatial attention in chronic neglect after stroke. RehAtt™ consists of a computer with monitor, 3D glasses, and a force feedback interface (Robotic pen) giving sensory motor activation to the contra-lesional arm. The software combines visual scanning training with multi-sensory stimulation in 3D virtual reality (VR) game environment. Fifteen stroke patients with chronic neglect (duration > 6 month) had repeated baseline evaluations to confirm stability of symptoms. There were no test-retest effects for any of the tests. Thereafter, all patients trained 15 h in RehAtt™ (3 × 1 h for 5 weeks). A neglect test battery and Catherine Bergego Scale, CBS, were used to assess behavioral outcome after intervention. CBS was also used at a 6-month follow-up. Using repeated measurement analysis improvements due to the training were found for Star cancellation test (p = 0.006), Baking tray task (p < 0.001), and Extinction test (p = 0.05). In the Posner task improvements were seen fewer missed targets (p = 0.024). CBS showed improvements in activities of daily life immediately after training (p < 0.01). After 6 months the patients still reported improvement in CBS. RehAtt™ is a new concept for rehabilitation of neglect. Training with the VR-method improved spatial attention and showed transfer to improved spatial attention in activities of daily living in chronic neglect. Our results are promising and merit further studies.

The construction of a high resolution crystal backscattering spectrometer HERMES I

DOE Office of Scientific and Technical Information (OSTI.GOV)

Larese, J.Z.

There is a need in the United States for a state-of-the-art, cold-neutron, crystal backscattering spectrometer (CBS) designed to investigate the structure and dynamics of condensed matter systems by the simultaneous utilization of long wavelength elastic diffraction and high-energy-resolution inelastic scattering. Cold neutron spectroscopy with CBS-type instruments has already made many important contributions to the study of atomic and molecular diffusion in biomaterials, polymers, semiconductors, liquid crystals, superionic conductors and the like. Such instruments have also been invaluable for ultra high resolution investigations of the low-lying quantum tunneling processes that provide direct insight into the dynamical response of solids at themore » lowest energies. Until relatively recently, however, all such instruments were located at steady-state reactors. This proposal describes HERMES I (High Energy Resolution Machines I) a CBS intended for installation at the LANSCE pulsed neutron facility of Los Alamos National Laboratory. As explained in detail in the main text, the authors propose to construct an updated, high-performance CBS which incorporates neutron techniques developed during the decade since IRIS was built, i.e., improved supermirror technology, a larger area crystal analyzer and high efficiency wire gas detectors. The instrument is designed in such a way as to be readily adaptable to future upgrades. HERMES I, they believe, will substantially expand the range and flexibility of neutron investigations in the United States and open new and potentially fruitful directions for condensed matter exploration. This document describes a implementation plan with a direct cost range between $4.5 to 5.6 M and scheduled duration of 39--45 months for identified alternatives.« less

Analysis of functioning and efficiency of a code blue system in a tertiary care hospital.

PubMed

Monangi, Srinivas; Setlur, Rangraj; Ramanathan, Ramprasad; Bhasin, Sidharth; Dhar, Mridul

2018-01-01

"Code blue" (CB) is a popular hospital emergency code, which is used by hospitals to alert their emergency response team of any cardiorespiratory arrest. The factors affecting the outcomes of emergencies are related to both the patient and the nature of the event. The primary objective was to analyze the survival rate and factors associated with survival and also practical problems related to functioning of a CB system (CBS). After the approval of hospital ethics committee, an analysis and audit was conducted of all patients on whom a CB had been called in our tertiary care hospital over 24 months. Data collected were demographic data, diagnosis, time of cardiac arrest and activation of CBS, time taken by CBS to reach the patient, presenting rhythm on arrival of CB team, details of cardiopulmonary resuscitation (CPR) such as duration and drugs given, and finally, events and outcomes. Chi-square test and logistic regression analysis were used to analyze the data. A total of 720 CB calls were initiated during the period. After excluding 24 patients, 694 calls were studied and analyzed. Six hundred and twenty were true calls and 74 were falls calls. Of the 620, 422 were cardiac arrests and 198 were medical emergencies. Overall survival was 26%. Survival in patients with cardiac arrests was 11.13%. Factors such as age, presenting rhythm, and duration of CPR were found to have a significant effect on survival. Problems encountered were personnel and equipment related. A CBS is effective in improving the resuscitation efforts and survival rates after inhospital cardiac arrests. Age, presenting rhythm at the time of arrest, and duration of CPR have significant effect on survival of the patient after a cardiac arrest. Technical and staff-related problems need to be considered and improved upon.

Anti-inflammatory Effect of Astaxanthin on the Sickness Behavior Induced by Diabetes Mellitus.

PubMed

Ying, Chang-jiang; Zhang, Fang; Zhou, Xiao-yan; Hu, Xiao-tong; Chen, Jing; Wen, Xiang-ru; Sun, Ying; Zheng, Kui-yang; Tang, Ren-xian; Song, Yuan-jian

2015-10-01

Chronic inflammation appears to play a critical role in sickness behavior caused by diabetes mellitus. Astaxanthin has been used in treating diabetes mellitus and diabetic complications because of its neuroprotective and anti-inflammatory actions. However, whether astaxanthin can improve sickness behavior induced by diabetes and its potential mechanisms are still unknown. The aim of this study was to investigate the effects of astaxanthin on diabetes-elicited abnormal behavior in mice and its corresponding mechanisms. An experimental diabetic model was induced by streptozotocin (150 mg/kg) and astaxanthin (25 mg/kg/day) was provided orally for 10 weeks. Body weight and water consumption were measured, and the sickness behavior was evaluated by the open field test (OFT) and closed field test (CFT). The expression of glial fibrillary acidic protein (GFAP) was measured, and the frontal cortical cleaved caspase-3 positive cells, interleukin-6 (IL-6), and interleukin-1β (IL-1β) expression levels were also investigated. Furthermore, cystathionine β-synthase (CBS) in the frontal cortex was detected to determine whether the protective effect of astaxanthin on sickness behavior in diabetic mice is closely related to CBS. As expected, we observed that astaxanthin improved general symptoms and significantly increase horizontal distance and the number of crossings in the OFT and CFT. Furthermore, data showed that astaxanthin could decrease GFAP-positive cells in the brain and down-regulate the cleaved caspase-3, IL-6, and IL-1β, and up-regulate CBS in the frontal cortex. These results suggest that astaxanthin provides neuroprotection against diabetes-induced sickness behavior through inhibiting inflammation, and the protective effects may involve CBS expression in the brain.

Metschnikowia drakensbergensis sp. nov. and Metschnikowia caudata sp. nov., endemic yeasts associated with Protea flowers in South Africa.

PubMed

de Vega, Clara; Guzmán, Beatriz; Steenhuisen, Sandy-Lynn; Johnson, Steven D; Herrera, Carlos M; Lachance, Marc-André

2014-11-01

In a taxonomic study of yeasts recovered from nectar of flowers and associated insects in South Africa, 11 strains were found to represent two novel species. Morphological and physiological characteristics and sequence analyses of the large-subunit rRNA gene D1/D2 region, as well as the actin, RNA polymerase II and elongation factor 2 genes, showed that the two novel species belonged to the genus Metschnikowia. Metschnikowia drakensbergensis sp. nov. (type strain EBD-CdVSA09-2(T) =CBS 13649(T) =NRRL Y-63721(T); MycoBank no. MB809688; allotype EBD-CdVSA10-2(A) =CBS13650(A) =NRRL Y-63720(A)) was recovered from nectar of Protea roupelliae and the beetle Heterochelus sp. This species belongs to the large-spored Metschnikowia clade and is closely related to Metschnikowia proteae, with which mating reactions and single-spored asci were observed. Metschnikowia caudata sp. nov. (type strain EBD-CdVSA08-1(T) =CBS 13651(T) =NRRL Y-63722(T); MycoBank no. MB809689; allotype EBD-CdVSA57-2(A) =CBS 13729(A) =NRRL Y-63723(A)) was isolated from nectar of Protea dracomontana, P. roupelliae and P. subvestita and a honeybee, and is a sister species to Candida hainanensis and Metschnikowia lopburiensis. Analyses of the four sequences demonstrated the existence of three separate phylotypes. Intraspecies matings led to the production of mature asci of unprecedented morphology, with a long, flexuous tail. A single ascospore was produced in all compatible crosses, regardless of sequence phylotype. The two species appear to be endemic to South Africa. The ecology and habitat specificity of these novel species are discussed in terms of host plant and insect host species. © 2014 IUMS.

Evaluation of Effectiveness and Cost‐Effectiveness of a Clinical Decision Support System in Managing Hypertension in Resource Constrained Primary Health Care Settings: Results From a Cluster Randomized Trial

PubMed Central

Anchala, Raghupathy; Kaptoge, Stephen; Pant, Hira; Di Angelantonio, Emanuele; Franco, Oscar H.; Prabhakaran, D.

2015-01-01

Background Randomized control trials from the developed world report that clinical decision support systems (DSS) could provide an effective means to improve the management of hypertension (HTN). However, evidence from developing countries in this regard is rather limited, and there is a need to assess the impact of a clinical DSS on managing HTN in primary health care center (PHC) settings. Methods and Results We performed a cluster randomized trial to test the effectiveness and cost‐effectiveness of a clinical DSS among Indian adult hypertensive patients (between 35 and 64 years of age), wherein 16 PHC clusters from a district of Telangana state, India, were randomized to receive either a DSS or a chart‐based support (CBS) system. Each intervention arm had 8 PHC clusters, with a mean of 102 hypertensive patients per cluster (n=845 in DSS and 783 in CBS groups). Mean change in systolic blood pressure (SBP) from baseline to 12 months was the primary endpoint. The mean difference in SBP change from baseline between the DSS and CBS at the 12th month of follow‐up, adjusted for age, sex, height, waist, body mass index, alcohol consumption, vegetable intake, pickle intake, and baseline differences in blood pressure, was −6.59 mm Hg (95% confidence interval: −12.18 to −1.42; P=0.021). The cost‐effective ratio for CBS and DSS groups was $96.01 and $36.57 per mm of SBP reduction, respectively. Conclusion Clinical DSS are effective and cost‐effective in the management of HTN in resource‐constrained PHC settings. Clinical Trial Registration URL: http://www.ctri.nic.in. Unique identifier: CTRI/2012/03/002476. PMID:25559011

Crystal structure of Halobacterium salinarum halorhodopsin with a partially depopulated primary chloride-binding site.

PubMed

Schreiner, Madeleine; Schlesinger, Ramona; Heberle, Joachim; Niemann, Hartmut H

2016-09-01

The transmembrane pump halorhodopsin in halophilic archaea translocates chloride ions from the extracellular to the cytoplasmic side upon illumination. In the ground state a tightly bound chloride ion occupies the primary chloride-binding site (CBS I) close to the protonated Schiff base that links the retinal chromophore to the protein. The light-triggered trans-cis isomerization of retinal causes structural changes in the protein associated with movement of the chloride ion. In reverse, chemical depletion of CBS I in Natronomonas pharaonis halorhodopsin (NpHR) through deprotonation of the Schiff base results in conformational changes of the protein: a state thought to mimic late stages of the photocycle. Here, crystals of Halobacterium salinarum halorhodopsin (HsHR) were soaked at high pH to provoke deprotonation of the Schiff base and loss of chloride. The crystals changed colour from purple to yellow and the occupancy of CBS I was reduced from 1 to about 0.5. In contrast to NpHR, this chloride depletion did not cause substantial conformational changes in the protein. Nevertheless, two observations indicate that chloride depletion could eventually result in structural changes similar to those found in NpHR. Firstly, the partially chloride-depleted form of HsHR has increased normalized B factors in the region of helix C that is close to CBS I and changes its conformation in NpHR. Secondly, prolonged soaking of HsHR crystals at high pH resulted in loss of diffraction. In conclusion, the conformation of the chloride-free protein may not be compatible with this crystal form of HsHR despite a packing arrangement that hardly restrains helices E and F that presumably move during ion transport.

The state of cell block variation and satisfaction in the era of molecular diagnostics and personalized medicine

PubMed Central

Crapanzano, John P.; Heymann, Jonas J.; Monaco, Sara; Nassar, Aziza; Saqi, Anjali

2014-01-01

Background: In the recent past, algorithms and recommendations to standardize the morphological, immunohistochemical and molecular classification of lung cancers on cytology specimens have been proposed, and several organizations have recommended cell blocks (CBs) as the preferred modality for molecular testing. Based on the literature, there are several different techniques available for CB preparation-suggesting that there is no standard. The aim of this study was to conduct a survey of CB preparation techniques utilized in various practice settings and analyze current issues, if any. Materials and Methods: A single E-mail with a link to an electronic survey was distributed to members of the American Society of Cytopathology and other pathologists. Questions pertaining to the participants’ practice setting and CBs-volume, method, quality and satisfaction-were included. Results: Of 95 respondents, 90/95 (94%) completed the survey and comprise the study group. Most participants practice in a community hospital/private practice (44%) or academic center (41%). On average, 14 CBs (range 0-50; median 10) are prepared by a laboratory daily. Over 10 methods are utilized: Plasma thrombin (33%), HistoGel (27%), Cellient automated cell block system (8%) and others (31%) respectively. Forty of 90 (44%) respondents are either unsatisfied or sometimes satisfied with their CB quality, with low-cellular yield being the leading cause of dissatisfaction. There was no statistical significance between the three most common CB preparation methods and satisfaction with quality. Discussion: Many are dissatisfied with their current method of CB preparation, and there is no consistent method to prepare CBs. In today's era of personalized medicine with an increasing array of molecular tests being applied to cytological specimens, there is a need for a standardized protocol for CB optimization to enhance cellularity. PMID:24799951

The state of cell block variation and satisfaction in the era of molecular diagnostics and personalized medicine.

PubMed

Crapanzano, John P; Heymann, Jonas J; Monaco, Sara; Nassar, Aziza; Saqi, Anjali

2014-01-01

In the recent past, algorithms and recommendations to standardize the morphological, immunohistochemical and molecular classification of lung cancers on cytology specimens have been proposed, and several organizations have recommended cell blocks (CBs) as the preferred modality for molecular testing. Based on the literature, there are several different techniques available for CB preparation-suggesting that there is no standard. The aim of this study was to conduct a survey of CB preparation techniques utilized in various practice settings and analyze current issues, if any. A single E-mail with a link to an electronic survey was distributed to members of the American Society of Cytopathology and other pathologists. Questions pertaining to the participants' practice setting and CBs-volume, method, quality and satisfaction-were included. Of 95 respondents, 90/95 (94%) completed the survey and comprise the study group. Most participants practice in a community hospital/private practice (44%) or academic center (41%). On average, 14 CBs (range 0-50; median 10) are prepared by a laboratory daily. Over 10 methods are utilized: Plasma thrombin (33%), HistoGel (27%), Cellient automated cell block system (8%) and others (31%) respectively. Forty of 90 (44%) respondents are either unsatisfied or sometimes satisfied with their CB quality, with low-cellular yield being the leading cause of dissatisfaction. There was no statistical significance between the three most common CB preparation methods and satisfaction with quality. Many are dissatisfied with their current method of CB preparation, and there is no consistent method to prepare CBs. In today's era of personalized medicine with an increasing array of molecular tests being applied to cytological specimens, there is a need for a standardized protocol for CB optimization to enhance cellularity.

Effects of Oxygen Availability on Acetic Acid Tolerance and Intracellular pH in Dekkera bruxellensis.

PubMed

Capusoni, Claudia; Arioli, Stefania; Zambelli, Paolo; Moktaduzzaman, M; Mora, Diego; Compagno, Concetta

2016-08-01

The yeast Dekkera bruxellensis, associated with wine and beer production, has recently received attention, because its high ethanol and acid tolerance enables it to compete with Saccharomyces cerevisiae in distilleries that produce fuel ethanol. We investigated how different cultivation conditions affect the acetic acid tolerance of D. bruxellensis We analyzed the ability of two strains (CBS 98 and CBS 4482) exhibiting different degrees of tolerance to grow in the presence of acetic acid under aerobic and oxygen-limited conditions. We found that the concomitant presence of acetic acid and oxygen had a negative effect on D. bruxellensis growth. In contrast, incubation under oxygen-limited conditions resulted in reproducible growth kinetics that exhibited a shorter adaptive phase and higher growth rates than those with cultivation under aerobic conditions. This positive effect was more pronounced in CBS 98, the more-sensitive strain. Cultivation of CBS 98 cells under oxygen-limited conditions improved their ability to restore their intracellular pH upon acetic acid exposure and to reduce the oxidative damage to intracellular macromolecules caused by the presence of acetic acid. This study reveals an important role of oxidative stress in acetic acid tolerance in D. bruxellensis, indicating that reduced oxygen availability can protect against the damage caused by the presence of acetic acid. This aspect is important for optimizing industrial processes performed in the presence of acetic acid. This study reveals an important role of oxidative stress in acetic acid tolerance in D. bruxellensis, indicating that reduced oxygen availability can have a protective role against the damage caused by the presence of acetic acid. This aspect is important for the optimization of industrial processes performed in the presence of acetic acid. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Evaluation of background soil and air polychlorinated biphenyl (PCB) concentrations on a hill at the outskirts of a metropolitan city.

PubMed

Kuzu, S Levent; Saral, Arslan; Güneş, Gülten; Karadeniz, Aykut

2016-07-01

Air and soil sampling was conducted inside a forested area for 22 months. The sampling location is situated to the north of a metropolitan city. Average atmospheric gas and particle concentrations were found to be 180 and 28 pg m(-3) respectively, while that of soil phase was detected to be 3.2 ng g(-1) on dry matter, The congener pairs of PCB#4-10 had the highest contribution to each medium. TEQ concentration was 0.10 pg m(-3), 0.07 pg m(-3), 21.92 pg g(-1), for gas, particle and soil phases, respectively. PCB#126 and PCB#169 contributed to over 99% of the entire TEQ concentrations for each medium. Local sources were investigated by conditional probability function (CPF) and soil/air fugacity. Landfilling area and medical waste incinerator, located to the 8 km northeast, contributed to ambient concentrations, especially in terms of dioxin-like congeners. The industrial settlement (called Dilovasi being to the east southeast of 60 km distant) contributed from southeast direction. Further sources were identified by potential source contribution function (PSCF). Sources at close proximity had high contribution. Air mass transportation from Aliaga industrial region (being to the southwest of 300 km distant) moderately contributed to ambient concentrations. Low molecular weight congeners were released from soil body. 5-CBs and 6-CBs were close to equilibrium state between soil/air interfaces. PCB#171 was close to equilibrium and PCB#180 was likely to evaporate from soil, which constitute 7-CBs. PCB#199, representing 8-CBs deposited to soil. 9-CB (PCB#207) was in equilibrium between soil and air phases. Copyright © 2016 Elsevier Ltd. All rights reserved.

Formation of PAH-DNA adducts after in vivo and vitro exposure of rats and lung cells to different commercial carbon blacks.

PubMed

Borm, Paul J A; Cakmak, Gonca; Jermann, Erich; Weishaupt, Christel; Kempers, Pascal; van Schooten, Frederik Jan; Oberdörster, Günter; Schins, Roel P F

2005-06-01

The current study was designed to test the possible release and bioavailability of polycyclic aromatic hydrocarbons (PAHs) from a set of commercial carbon blacks (CBs) as well as the ability of these PAHs to form bulky DNA adducts. In four commercial CBs (Printex 90, Sterling V, N330, Lampblack 101), leaching of PAH was examined through (1) release of parent PAHs in saline with or without surfactant, and (2) PAH adducts in lung epithelial cells (A549) or in rat lungs after exposure to two CBs (Printex 90, Sterling V) for 13 weeks (50 mg/m(3)). In vitro experiments were done with original and extracted particles, as well as organic extracts of CB in DMSO. As positive controls, B[a]P (0.03 microM) and a mixture of 16 PAHs (0.1 microM) were used. No leaching of PAHs was measured in saline or surfactant-containing saline. In vitro incubations with CB particles (30-300 microg/cm(2)) revealed no adduct spots except for Sterling V. However, the spot was not concentration dependent and remains unidentified. Lung DNA from rats after inhalation of Printex 90 or Sterling V showed no spots related to PAH-DNA adduct formation compared to sham-exposed rats. The results suggest that PAHs are very tightly bound to these CBs. Only using organic extracts or particles of low-surface Sterling V, with high PAH content, PAHs may become available to form PAH-DNA adducts. However, the in vitro conditions showing this effect will not be encountered in vivo and renders this mechanism in particle-induced lung cancer at in vivo exposures highly unlikely.

Effects of Oxygen Availability on Acetic Acid Tolerance and Intracellular pH in Dekkera bruxellensis

PubMed Central

Capusoni, Claudia; Arioli, Stefania; Zambelli, Paolo; Moktaduzzaman, M.; Mora, Diego

2016-01-01

ABSTRACT The yeast Dekkera bruxellensis, associated with wine and beer production, has recently received attention, because its high ethanol and acid tolerance enables it to compete with Saccharomyces cerevisiae in distilleries that produce fuel ethanol. We investigated how different cultivation conditions affect the acetic acid tolerance of D. bruxellensis. We analyzed the ability of two strains (CBS 98 and CBS 4482) exhibiting different degrees of tolerance to grow in the presence of acetic acid under aerobic and oxygen-limited conditions. We found that the concomitant presence of acetic acid and oxygen had a negative effect on D. bruxellensis growth. In contrast, incubation under oxygen-limited conditions resulted in reproducible growth kinetics that exhibited a shorter adaptive phase and higher growth rates than those with cultivation under aerobic conditions. This positive effect was more pronounced in CBS 98, the more-sensitive strain. Cultivation of CBS 98 cells under oxygen-limited conditions improved their ability to restore their intracellular pH upon acetic acid exposure and to reduce the oxidative damage to intracellular macromolecules caused by the presence of acetic acid. This study reveals an important role of oxidative stress in acetic acid tolerance in D. bruxellensis, indicating that reduced oxygen availability can protect against the damage caused by the presence of acetic acid. This aspect is important for optimizing industrial processes performed in the presence of acetic acid. IMPORTANCE This study reveals an important role of oxidative stress in acetic acid tolerance in D. bruxellensis, indicating that reduced oxygen availability can have a protective role against the damage caused by the presence of acetic acid. This aspect is important for the optimization of industrial processes performed in the presence of acetic acid. PMID:27235432

[Charles Bonnet syndrome precipitated by brimonidine].

PubMed

García-Catalán, M R; Arriola-Villalobos, P; Santos-Bueso, E; Gil-de-Bernabé, J; Díaz-Valle, D; Benítez-del-Castillo, J M; García-Sánchez, J

2013-09-01

An 81-year-old woman with age-related macular degeneration and pseudoexfoliative glaucoma developed visual hallucinations (faces, flowers and frames) shortly after beginning brimonidine drops. Neurologic and psychiatric examination was normal. Visual hallucinations disappeared within 10 days after discontinuing the drug. The Charles Bonnet syndrome (CBS) is characterised by complex visual hallucinations in elderly patients in the setting of significant visual impairment without any psychiatric symptoms. Awareness of CBS among ophthalmologist is essential. Clinicians should treat visual impairment and be aware of possible visual hallucinations in patients treated with brimonidine. Copyright © 2010 Sociedad Española de Oftalmología. Published by Elsevier Espana. All rights reserved.

Ogataea phyllophila sp. nov., Candida chumphonensis sp. nov. and Candida mattranensis sp. nov., three methylotrophic yeast species from phylloplane in Thailand.

PubMed

Koowadjanakul, Nampueng; Jindamorakot, Sasitorn; Yongmanitchai, Wichien; Limtong, Savitree

2011-08-01

Five strains (LN12, LN14(T), LN15(T), LN16 and LN17(T)) representing three novel methylotrophic yeast species were isolated from the external surface of plant leaves by three-consecutive enrichments. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, the sequence analysis of the D1/D2 domain of the large subunit (LSU) rRNA gene and the phylogenetic analysis, the five strains were assigned to be one novel Ogataea species and two novel Candida species. Three strains (LN12, LN14(T) and LN16) represent a single novel species of the genus Ogataea, for which the name Ogataea phyllophila sp. nov. is proposed. The type strain is LN14(T) (= BCC 42666(T) = NBRC 107780(T) = CBS 12095(T)). Strain LN15(T) was assigned to be Candida chumphonensis sp. nov. (type strain LN15(T) = BCC 42667(T) = NBRC 107781(T) = CBS 12096(T)). Strain LN17(T) represented another novel species of Candida that was named Candida mattranensis sp. nov. (type strain LN17(T) = BCC 42668(T) = NBRC 107782(T) = CBS 12097(T)).

Change in single cystathionine β-synthase domain-containing protein from a bent to flat conformation upon adenosine monophosphate binding.

PubMed

Jeong, Byung-Cheon; Park, Si Hoon; Yoo, Kyoung Shin; Shin, Jeong Sheop; Song, Hyun Kyu

2013-07-01

Cystathionine β-synthase (CBS) domains are small intracellular modules that can act as binding domains for adenosine derivatives, and they may regulate the activity of associated enzymes or other functional domains. Among these, the single CBS domain-containing proteins, CBSXs, from Arabidopsis thaliana, have recently been identified as redox regulators of the thioredoxin system. Here, the crystal structure of CBSX2 in complex with adenosine monophosphate (AMP) is reported at 2.2Å resolution. The structure of dimeric CBSX2 with bound-AMP is shown to be approximately flat, which is in stark contrast to the bent form of apo-CBSXs. This conformational change in quaternary structure is triggered by a local structural change of the unique α5 helix, and by moving each loop P into an open conformation to accommodate incoming ligands. Furthermore, subtle rearrangement of the dimer interface triggers movement of all subunits, and consequently, the bent structure of the CBSX2 dimer becomes a flat structure. This reshaping of the structure upon complex formation with adenosine-containing ligand provides evidence that ligand-induced conformational reorganization of antiparallel CBS domains is an important regulatory mechanism. Copyright © 2013 Elsevier Inc. All rights reserved.

Dephosphorylation of survival motor neurons (SMN) by PPM1G/PP2Cγ governs Cajal body localization and stability of the SMN complex

PubMed Central

Petri, Sebastian; Grimmler, Matthias; Over, Sabine; Fischer, Utz; Gruss, Oliver J.

2007-01-01

The survival motor neuron (SMN) complex functions in maturation of uridine-rich small nuclear ribonucleoprotein (RNP) particles. SMN mediates the cytoplasmic assembly of Sm proteins onto uridine-rich small RNAs, and then participates in targeting RNPs to nuclear Cajal bodies (CBs). Recent studies have suggested that phosphorylation might control localization and function of the SMN complex. Here, we show that the nuclear phosphatase PPM1G/PP2Cγ interacts with and dephosphorylates the SMN complex. Small interfering RNA knockdown of PPM1G leads to an altered phosphorylation pattern of SMN and Gemin3, loss of SMN from CBs, and reduced stability of SMN. Accumulation in CBs is restored upon overexpression of catalytically active, but not that of inactive, PPM1G. This demonstrates that PPM1G's phosphatase activity is necessary to maintain SMN subcellular distribution. Concomitant knockdown of unr interacting protein (unrip), a component implicated in cytoplasmic retention of the SMN complex, also rescues the localization defects. Our data suggest that an interplay between PPM1G and unrip determine compartment-specific phosphorylation patterns, localization, and function of the SMN complex. PMID:17984321

An ab initio benchmark study of the H + CO --> HCO reaction

NASA Technical Reports Server (NTRS)

Woon, D. E.

1996-01-01

The H + CO --> HCO reaction has been characterized with correlation consistent basis sets at five levels of theory in order to benchmark the sensitivities of the barrier height and reaction ergicity to the one-electron and n-electron expansions of the electronic wave function. Single and multireference methods are compared and contrasted. The coupled cluster method RCCSD(T) was found to be in very good agreement with Davidson-corrected internally-contracted multireference configuration interaction (MRCI+Q). Second-order Moller-Plesset perturbation theory (MP2) was also employed. The estimated complete basis set (CBS) limits for the barrier height (in kcal/mol) for the five methods, including harmonic zero-point energy corrections, are MP2, 4.66; RCCSD, 4.78; RCCSD(T), 4.15; MRCI, 5.10; and MRCI+Q, 4.07. Similarly, the estimated CBS limits for the ergicity of the reaction are: MP2, -17.99; RCCSD, -13.34; RCCSD(T), -13.79; MRCI, -11.46; and MRCI+Q, -13.70. Additional basis set explorations for the RCCSD(T) method demonstrate that aug-cc-pVTZ sets, even with some functions removed, are sufficient to reproduce the CBS limits to within 0.1-0.3 kcal/mol.

Theoretical investigation of gas-phase molecular complex formation between 2-hydroxy thiophenol and a water molecule.

PubMed

Kumar Deb, Debojit; Sarkar, Biplab

2017-01-18

The torsional potential of OH and SH rotations in 2-hydroxy thiophenol is systematically studied using the MP2 ab initio method. The outcome of state-of-the-art calculations is used in the investigation of the structures and conformational preferences of 2-hydroxy thiophenol and aims at further interaction studies with a gas phase water molecule. SCS-MP2 and CCSD(T) complete basis set (CBS) limit interaction energies for these complexes are presented. The SCS-MP2/CBS limit is achieved using various two-point extrapolation methods with aug-cc-pVDZ and aug-cc-pVTZ basis sets. The CCSD(T) correction term is determined as the difference between CCSD(T) and SCS-MP2 interaction energies calculated using a smaller basis set. The effect of counterpoise correction on the extrapolation to the CBS limit is discussed. The performance of DFT based wB97XD, M06-2X and B3LYP-D3 functionals is tested against the benchmark energy from ab initio calculations. Hydrogen bond interactions are characterized by carrying out QTAIM, NCIPLOT, NBO and SAPT analyses.

Effect of oxygenation and temperature on glucose-xylose fermentation in Kluyveromyces marxianus CBS712 strain

PubMed Central

2014-01-01

Background The yeast Kluyveromyces marxianus features specific traits that render it attractive for industrial applications. These include production of ethanol which, together with thermotolerance and the ability to grow with a high specific growth rate on a wide range of substrates, could make it an alternative to Saccharomyces cerevisiae as an ethanol producer. However, its ability to co-ferment C5 and C6 sugars under oxygen-limited conditions is far from being fully characterized. Results In the present study, K. marxianus CBS712 strain was cultivated in defined medium with glucose and xylose as carbon source. Ethanol fermentation and sugar consumption of CBS712 were investigated under different oxygen supplies (1.75%, 11.00% and 20.95% of O2) and different temperatures (30°C and 41°C). By decreasing oxygen supply, independently from the temperature, both biomass production as well as sugar utilization rate were progressively reduced. In all the tested conditions xylose consumption followed glucose exhaustion. Therefore, xylose metabolism was mainly affected by oxygen depletion. Loss in cell viability cannot explain the decrease in sugar consumption rates, as demonstrated by single cell analyses, while cofactor imbalance is commonly considered as the main cause of impairment of the xylose reductase (KmXR) - xylitol dehydrogenase (KmXDH) pathway. Remarkably, when these enzyme activities were assayed in vitro, a significant decrease was observed together with oxygen depletion, not ascribed to reduced transcription of the corresponding genes. Conclusions In the present study both oxygen supply and temperature were shown to be key parameters affecting the fermentation capability of sugars in the K. marxianus CBS712 strain. In particular, a direct correlation was observed between the decreased efficiency to consume xylose with the reduced specific activity of the two main enzymes (KmXR and KmXDH) involved in its catabolism. These data suggest that, in addition to the impairment of the oxidoreductive pathway being determined by the cofactor imbalance, post-transcriptional and/or post-translational regulation of the pathway enzymes contributes to the efficiency of xylose catabolism in micro-aerobic conditions. Overall, the presented work provides novel information on the fermentation capability of the CBS712 strain that is currently considered as the reference strain of the genus K. marxianus. PMID:24712908

The challenges of reshaping disease specific and care oriented community based services towards comprehensive goals: a situation appraisal in the Western Cape Province, South Africa.

PubMed

Schneider, Helen; Schaay, Nikki; Dudley, Lilian; Goliath, Charlyn; Qukula, Tobeka

2015-09-30

Similar to other countries in the region, South Africa is currently reorienting a loosely structured and highly diverse community care system that evolved around HIV and TB, into a formalized, comprehensive and integrated primary health care outreach programme, based on community health workers (CHWs). While the difficulties of establishing national CHW programmes are well described, the reshaping of disease specific and care oriented community services, based outside the formal health system, poses particular challenges. This paper is an in-depth case study of the challenges of implementing reforms to community based services (CBS) in one province of South Africa. A multi-method situation appraisal of CBS in the Western Cape Province was conducted over eight months in close collaboration with provincial stakeholders. The appraisal mapped the roles and service delivery, human resource, financing and governance arrangements of an extensive non-governmental organisation (NGO) contracted and CHW based service delivery infrastructure that emerged over 15-20 years in this province. It also gathered the perspectives of a wide range of actors - including communities, users, NGOs, PHC providers and managers - on the current state and future visions of CBS. While there was wide support for new approaches to CBS, there are a number of challenges to achieving this. Although largely government funded, the community based delivery platform remains marginal to the formal public primary health care (PHC) and district health systems. CHW roles evolved from a system of home based care and are limited in scope. There is a high turnover of cadres, and support systems (supervision, monitoring, financing, training), coordination between CHWs, NGOs and PHC facilities, and sub-district capacity for planning and management of CBS are all poorly developed. Reorienting community based services that have their origins in care responses to HIV and TB presents an inter-related set of resource mobilisation, system design and governance challenges. These include not only formalising community based teams themselves, but also the forging of new roles, relationships and mind-sets within the primary health care system, and creating greater capacity for contracting and engaging a plural set of actors - government, NGO and community - at district and sub-district level.

Structure and binding energy of the H2S dimer at the CCSD(T) complete basis set limit.

PubMed

Lemke, Kono H

2017-06-21

This study presents results for the binding energy and geometry of the H 2 S dimer which have been computed using Møller-Plesset perturbation theory (MP2, MP4) and coupled cluster (CCSD, CCSD(T)) calculations with basis sets up to aug-cc-pV5Z. Estimates of D e , E ZPE , D o , and dimer geometry have been obtained at each level of theory by taking advantage of the systematic convergence behavior toward the complete basis set (CBS) limit. The CBS limit binding energy values of D e are 1.91 (MP2), 1.75 (MP4), 1.41 (CCSD), and 1.69 kcal/mol (CCSD[T]). The most accurate values for the equilibrium S-S distance r SS (without counterpoise correction) are 4.080 (MP2/aug-cc-pV5Z), 4.131 (MP4/aug-cc-pVQZ), 4.225 (CCSD/aug-cc-pVQZ), and 4.146 Å (CCSD(T)/aug-cc-pVQZ). This study also evaluates the effect of counterpoise correction on the H 2 S dimer geometry and binding energy. As regards the structure of (H 2 S) 2 , MPn, CCSD, and CCSD(T) level values of r SS , obtained by performing geometry optimizations on the counterpoise-corrected potential energy surface, converge systematically to CBS limit values of 4.099 (MP2), 4.146 (MP4), 4.233 (CCSD), and 4.167 Å (CCSD(T)). The corresponding CBS limit values of the equilibrium binding energy D e are 1.88 (MP2), 1.76 (MP4), 1.41 (CCSD), and 1.69 kcal/mol (CCSD(T)), the latter in excellent agreement with the measured binding energy value of 1.68 ± 0.02 kcal/mol reported by Ciaffoni et al. [Appl. Phys. B 92, 627 (2008)]. Combining CBS electronic binding energies D e with E ZPE predicted by CCSD(T) vibrational second-order perturbation theory calculations yields D o = 1.08 kcal/mol, which is around 0.6 kcal/mol smaller than the measured value of 1.7 ± 0.3 kcal/mol. Overall, the results presented here demonstrate that the application of high level calculations, in particular CCSD(T), in combination with augmented correlation consistent basis sets provides valuable insight into the structure and energetics of the hydrogen sulfide dimer.

Effect of oxygenation and temperature on glucose-xylose fermentation in Kluyveromyces marxianus CBS712 strain.

PubMed

Signori, Lorenzo; Passolunghi, Simone; Ruohonen, Laura; Porro, Danilo; Branduardi, Paola

2014-04-08

The yeast Kluyveromyces marxianus features specific traits that render it attractive for industrial applications. These include production of ethanol which, together with thermotolerance and the ability to grow with a high specific growth rate on a wide range of substrates, could make it an alternative to Saccharomyces cerevisiae as an ethanol producer. However, its ability to co-ferment C5 and C6 sugars under oxygen-limited conditions is far from being fully characterized. In the present study, K. marxianus CBS712 strain was cultivated in defined medium with glucose and xylose as carbon source. Ethanol fermentation and sugar consumption of CBS712 were investigated under different oxygen supplies (1.75%, 11.00% and 20.95% of O2) and different temperatures (30°C and 41°C). By decreasing oxygen supply, independently from the temperature, both biomass production as well as sugar utilization rate were progressively reduced. In all the tested conditions xylose consumption followed glucose exhaustion. Therefore, xylose metabolism was mainly affected by oxygen depletion. Loss in cell viability cannot explain the decrease in sugar consumption rates, as demonstrated by single cell analyses, while cofactor imbalance is commonly considered as the main cause of impairment of the xylose reductase (KmXR) - xylitol dehydrogenase (KmXDH) pathway. Remarkably, when these enzyme activities were assayed in vitro, a significant decrease was observed together with oxygen depletion, not ascribed to reduced transcription of the corresponding genes. In the present study both oxygen supply and temperature were shown to be key parameters affecting the fermentation capability of sugars in the K. marxianus CBS712 strain. In particular, a direct correlation was observed between the decreased efficiency to consume xylose with the reduced specific activity of the two main enzymes (KmXR and KmXDH) involved in its catabolism. These data suggest that, in addition to the impairment of the oxidoreductive pathway being determined by the cofactor imbalance, post-transcriptional and/or post-translational regulation of the pathway enzymes contributes to the efficiency of xylose catabolism in micro-aerobic conditions. Overall, the presented work provides novel information on the fermentation capability of the CBS712 strain that is currently considered as the reference strain of the genus K. marxianus.

Structure and binding energy of the H2S dimer at the CCSD(T) complete basis set limit

NASA Astrophysics Data System (ADS)

Lemke, Kono H.

2017-06-01

This study presents results for the binding energy and geometry of the H2S dimer which have been computed using Møller-Plesset perturbation theory (MP2, MP4) and coupled cluster (CCSD, CCSD(T)) calculations with basis sets up to aug-cc-pV5Z. Estimates of De, EZPE, Do, and dimer geometry have been obtained at each level of theory by taking advantage of the systematic convergence behavior toward the complete basis set (CBS) limit. The CBS limit binding energy values of De are 1.91 (MP2), 1.75 (MP4), 1.41 (CCSD), and 1.69 kcal/mol (CCSD[T]). The most accurate values for the equilibrium S-S distance rSS (without counterpoise correction) are 4.080 (MP2/aug-cc-pV5Z), 4.131 (MP4/aug-cc-pVQZ), 4.225 (CCSD/aug-cc-pVQZ), and 4.146 Å (CCSD(T)/aug-cc-pVQZ). This study also evaluates the effect of counterpoise correction on the H2S dimer geometry and binding energy. As regards the structure of (H2S)2, MPn, CCSD, and CCSD(T) level values of rSS, obtained by performing geometry optimizations on the counterpoise-corrected potential energy surface, converge systematically to CBS limit values of 4.099 (MP2), 4.146 (MP4), 4.233 (CCSD), and 4.167 Å (CCSD(T)). The corresponding CBS limit values of the equilibrium binding energy De are 1.88 (MP2), 1.76 (MP4), 1.41 (CCSD), and 1.69 kcal/mol (CCSD(T)), the latter in excellent agreement with the measured binding energy value of 1.68 ± 0.02 kcal/mol reported by Ciaffoni et al. [Appl. Phys. B 92, 627 (2008)]. Combining CBS electronic binding energies De with EZPE predicted by CCSD(T) vibrational second-order perturbation theory calculations yields Do = 1.08 kcal/mol, which is around 0.6 kcal/mol smaller than the measured value of 1.7 ± 0.3 kcal/mol. Overall, the results presented here demonstrate that the application of high level calculations, in particular CCSD(T), in combination with augmented correlation consistent basis sets provides valuable insight into the structure and energetics of the hydrogen sulfide dimer.

Multi-temporal Scale Analysis of Environmental Control on Net Ecosystem Exchange of CO2 in Forest Ecosystems

NASA Astrophysics Data System (ADS)

Zhang, Mi; Yu, Guirui; Zhuang, Jie; Gentry, Randy; Koirala, Shesh; Zhang, Leiming; Sun, Xiaomin; Han, Shijie; Yan, Junhua

2013-04-01

Multi-temporal scale analysis of environmental control on forest ecosystem carbon budget is a basis for understanding the responses and adaptation of forest carbon cycle to climate change. In this study, we chose two typical forest ecosystems, Changbaishan temperate mixed forest (CBS) in northeastern China and Dinghushan subtropical evergreen broad-leaved forest (DHS) in southern China to identify the changes in environmental control on net ecosystem exchange of carbon dioxide (NEE) with the temporal scales. The analysis was made based on the flux and routine meteorological data measured during the period from 2005 to 2008. These time series data were analyzed using wavelet and cross wavelet transform. The results showed that NEE had significant daily and annual periodic variation in the two types of forest ecosystem. NEE at CBS and DHS showed semi-annual (176 days) and seasonal (88-104 days) periodic variations, respectively. Photosynthetically active radiation (PAR), vapor pressure deficient (VPD), air temperature (Ta), soil temperature (Ts, at 5-cm depth) controlled daily variation of NEE as indicated by the significant high common power of cross wavelet transform spectrums between NEE and these factors. Similarly, Ta, VPD, and precipitation (P) controlled annual variation of NEE at CBS. However, Ta, PAR, and soil water content (SWC, at 5-cm depth) dominated the annual variation of NEE at DHS. An anti-phase between NEE and PAR at daily scale in the two forest ecosystems demonstrated an agreement of the variation of NEE with PAR, with rising sunlight corresponding with increased net carbon uptake. At annual scale, phase angles between NEE and Ta and between NEE and P were -170° and 176°, respectively at CBS. At DHS, phase angle between NEE and VPD was smallest at annual scale. The results indicated that the peak of net carbon uptake seasonal variation and the peaks of P and Ta seasonal variations occurred at the same month at CBS. But, at DHS, seasonal variation of net carbon uptake was in agreement with that of VPD at annual scale. This study showed that wavelet analysis was an effective approach to identifying the temporal pattern of environmental control on carbon exchange between ecosystem and the atmosphere.

Hemizygosity of transsulfuration genes confers increased vulnerability against acetaminophen-induced hepatotoxicity in mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hagiya, Yoshifumi; Kamata, Shotaro; Mitsuoka, Saya

2015-01-15

The key mechanism for acetaminophen hepatotoxicity is cytochrome P450 (CYP)-dependent formation of N-acetyl-p-benzoquinone imine, a potent electrophile that forms protein adducts. Previous studies revealed the fundamental role of glutathione, which binds to and detoxifies N-acetyl-p-benzoquinone imine. Glutathione is synthesized from cysteine in the liver, and N-acetylcysteine is used as a sole antidote for acetaminophen poisoning. Here, we evaluated the potential roles of transsulfuration enzymes essential for cysteine biosynthesis, cystathionine β-synthase (CBS) and cystathionine γ-lyase (CTH), in acetaminophen hepatotoxicity using hemizygous (Cbs{sup +/−} or Cth{sup +/−}) and homozygous (Cth{sup −/−}) knockout mice. At 4 h after intraperitoneal acetaminophen injection, serum alaninemore » aminotransferase levels were highly elevated in Cth{sup −/−} mice at 150 mg/kg dose, and also in Cbs{sup +/−} or Cth{sup +/−} mice at 250 mg/kg dose, which was associated with characteristic centrilobular hepatocyte oncosis. Hepatic glutathione was depleted while serum malondialdehyde accumulated in acetaminophen-injected Cth{sup −/−} mice but not wild-type mice, although glutamate–cysteine ligase (composed of catalytic [GCLC] and modifier [GCLM] subunits) became more activated in the livers of Cth{sup −/−} mice with lower K{sub m} values for Cys and Glu. Proteome analysis using fluorescent two-dimensional difference gel electrophoresis revealed 47 differentially expressed proteins after injection of 150 mg acetaminophen/kg into Cth{sup −/−} mice; the profiles were similar to 1000 mg acetaminophen/kg-treated wild-type mice. The prevalence of Cbs or Cth hemizygosity is estimated to be 1:200–300 population; therefore, the deletion or polymorphism of either transsulfuration gene may underlie idiosyncratic acetaminophen vulnerability along with the differences in Cyp, Gclc, and Gclm gene activities. - Highlights: • Cbs{sup +/−}, Cth{sup +/−}, and especially Cth{sup −/−} mice were susceptible to APAP hepatic injury. • Hepatic glutathione became rapidly depleted upon APAP injection in Cth{sup −/−} mice. • Hepatic glutamate–cysteine ligase was activated by APAP injection and CTH deletion. • 2D DIGE identified 47 differentially expressed hepatic proteins by APAP injection. • Both transsulfuration enzymes are essential for protection against APAP injury.« less

Influence of Chlorine Substituents on Rates of Oxidation of Chlorinated Biphenyls by the Biphenyl Dioxygenase of Burkholderia sp. Strain LB400

PubMed Central

Arnett, Clint M.; Parales, Juan V.; Haddock, John D.

2000-01-01

Biphenyl dioxygenase from Burkholderia (Pseudomonas) sp. strain LB400 catalyzes the first reaction of a pathway for the degradation of biphenyl and a broad range of chlorinated biphenyls (CBs). The effect of chlorine substituents on catalysis was determined by measuring the specific activity of the enzyme with biphenyl and 18 congeners. The catalytic oxygenase component was purified and incubated with individual CBs in the presence of electron transport proteins and cofactors that were required for enzyme activity. The rate of depletion of biphenyl from the assay mixture and the rate of formation of cis-biphenyl 2,3-dihydrodiol, the oxidation product, were almost equal, indicating that the assay accurately measured enzyme-specific activity. Four classes of CBs were defined based on their oxidation rates. Class I contained 3-CB and 2,5-CB, which gave rates that were approximately twice that of biphenyl. Class II contained 2,5,3′,4′-CB, 2,3,2′,5′-CB, 2,3,4,5-CB, 2,3,2′,3′-CB, 2,4,5,2′,5′-CB, 2,5,3′-CB, 2,5,4′-CB, 2-CB, and 3,4,5-CB, which gave rates that ranged from 97 to 35% of the biphenyl rate. Class III contained only 2,3,4,2′,5′-CB, which gave a rate that was 4% of the biphenyl rate. Class IV contained 2,4,4′-CB, 2,4,2′,4′-CB, 3,4,5,2′-CB, 3,4,5,3′-CB, 3,5,3′,5′-CB, and 3,4,5,2′,5′-CB, which showed no detectable depletion. Rates were not significantly correlated with the aqueous solubilities of the CBs or the number of chlorine substituents on the rings. Oxidation products were detected for all class I, II, and III congeners and were identified as chlorinated cis-dihydrodiols for classes I and II. The specificity of biphenyl dioxygenase for the CBs examined in this study was determined by the relative positions of the chlorine substituents on the aromatic rings rather than the number of chlorine substituents on the rings. PMID:10877788

Modeling σ-Bond Activations by Nickel(0) Beyond Common Approximations: How Accurately Can We Describe Closed-Shell Oxidative Addition Reactions Mediated by Low-Valent Late 3d Transition Metal?

PubMed

Hu, Lianrui; Chen, Kejuan; Chen, Hui

2017-10-10

Accurate modelings of reactions involving 3d transition metals (TMs) are very challenging to both ab initio and DFT approaches. To gain more knowledge in this field, we herein explored typical σ-bond activations of H-H, C-H, C-Cl, and C-C bonds promoted by nickel(0), a low-valent late 3d TM. For the key parameters of activation energy (ΔE ‡ ) and reaction energy (ΔE R ) for these reactions, various issues related to the computational accuracy were systematically investigated. From the scrutiny of convergence issue with one-electron basis set, augmented (A) basis functions are found to be important, and the CCSD(T)/CBS level with complete basis set (CBS) limit extrapolation based on augmented double-ζ and triple-ζ basis pair (ADZ and ATZ), which produces deviations below 1 kcal/mol from the reference, is recommended for larger systems. As an alternative, the explicitly correlated F12 method can accelerate the basis set convergence further, especially after its CBS extrapolations. Thus, the CCSD(T)-F12/CBS(ADZ-ATZ) level with computational cost comparable to the conventional CCSD(T)/CBS(ADZ-ATZ) level, is found to reach the accuracy of the conventional CCSD(T)/A5Z level, which produces deviations below 0.5 kcal/mol from the reference, and is also highly recommendable. Scalar relativistic effects and 3s3p core-valence correlation are non-negligible for achieving chemical accuracy of around 1 kcal/mol. From the scrutiny of convergence issue with the N-electron basis set, in comparison with the reference CCSDTQ result, CCSD(T) is found to be able to calculate ΔE ‡ quite accurately, which is not true for the ΔE R calculations. Using highest-level CCSD(T) results of ΔE ‡ in this work as references, we tested 18 DFT methods and found that PBE0 and CAM-B3LYP are among the three best performing functionals, irrespective of DFT empirical dispersion correction. With empirical dispersion correction included, ωB97XD is also recommendable due to its improved performance.

PCB and DDE methyl sulfones in mammals from Canada and Sweden

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bergman, A.; Kuroki, Hiroaki; Norstrom, R.J.

1994-01-01

Levels of PCB methyl sulfones (MeSO[sub 2]-CBs) and DDE methyl sulfones (MeSO[sub 2]-DDEs) have been determined in tissues from polar bear (Ursus martimus), beluga whale (Delphinapterus leucas), and false killer whale (Pseudorca crassidens) from the Canadian environment, and grey seal (Halichoerus grypus), otter (Lutra lutra), and wild mink (Mustela vison) from the Swedish environment. Up to 30 MeSO[sub 2]-CB congeners and three MeSO[sub 2]-DdE isomers were shown to be present in the analyzed tissues. The concentration of total MeSO[sub 2]-CBs ranged from 0.1 to 21 [mu]g/g extracted lipids. 3-MeSO[sub 2]-2,5,2[prime],4[prime],5[prime]-penta-CB is the dominating MeSO[sub 2]-CB congener in all the analyzedmore » samples, but the corresponding 4-MeSO[sub 2]-CB also is present in high concentrations. A smaller number of MeSO[sub 2]-CBs, always dominated by the meta-substituted MeSO[sub 2]-CBs, were present in livers of grey seal, otter, and mink than in adipose tissue or muscle. In all studied mammals the concentration of MeSO[sub 2]-CBs were higher in liver than in blubber or muscle. Seven PCB congeners were identified as precursors of the PCB methyl sulfones: 2,4,2[prime],5[prime]-tetra-CB (CB-49),2,5,3[prime],4[prime]-tetra-CB (CB-70), 2,4,5,2[prime],5[prime]-penta-CB (CB-101),2,3,4,5,2[prime],5[prime]-penta-CB (CB-87),2,3,6,2[prime],4[prime],5[prime]-hexa-CB (CB-149),2,3,4,2[prime],3[prime],6[prime]-hexa-CB (CB-132), and 2,3,4,2[prime],5[prime]-hexa-CB (CB-141). All species except beluga whale contained 3-MeSO[sub 2]-4,4[prime]-DDE, but at a much lower concentration in mink and otter than in the other mammals. Polar bear and grey seal liver also contained 2-MeSO[sub 2]-4,4[prime]-DDE. The concentration of 2- and 3-MeSo[sub 2]-DDE ranged from 0.01 to 1.3 [mu]g/g extracted lipids.« less

Chaotic bubbling and nonstagnant foams.

PubMed

Tufaile, Alberto; Sartorelli, José Carlos; Jeandet, Philippe; Liger-Belair, Gerard

2007-06-01

We present an experimental investigation of the agglomeration of bubbles obtained from a nozzle working in different bubbling regimes. This experiment consists of a continuous production of bubbles from a nozzle at the bottom of a liquid column, and these bubbles create a two-dimensional (2D) foam (or a bubble raft) at the top of this column. The bubbles can assemble in various dynamically stable arrangement, forming different kinds of foams in a liquid mixture of water and glycerol, with the effect that the bubble formation regimes influence the foam obtained from this agglomeration of bubbles. The average number of bubbles in the foam is related to the bubble formation frequency and the bubble mean lifetime. The periodic bubbling can generate regular or irregular foam, while a chaotic bubbling only generates irregular foam.

Approaching behavior of a pair of spherical bubbles in quiescent liquids

NASA Astrophysics Data System (ADS)

Sanada, Toshiyuki; Kusuno, Hiroaki

2015-11-01

Some unique motions related bubble-bubble interaction, such as equilibrium distance, wake induced lift force, have been proposed by theoretical analysis or numerical simulations. These motions are different from the solid spheres like DKT model (Drafting, Kissing and Tumbling). However, there is a lack of the experimental verification. In this study, we experimentally investigated the motion of a pair of bubbles initially positioned in-line configuration in ultrapure water or an aqueous surfactant solution. The bubble motion were observed by two high speed video cameras. The bubbles Reynolds number was ranged from 50 to 300 and bubbles hold the spherical shape in this range. In ultrapure water, initially the trailing bubble deviated from the vertical line on the leading bubble owing to the wake of the leading bubble. And then, the slight difference of the bubble radius changed the relative motion. When the trailing bubble slightly larger than the leading bubble, the trailing bubble approached to the leading bubble due to it's buoyancy difference. The bubbles attracted and collided only when the bubbles rising approximately side by side configuration. In addition, we will also discuss the motion of bubbles rising in an aqueous surfactant solution.

Measuring ECS Interaction with Biomembranes.

PubMed

Angelucci, Clotilde B; Sabatucci, Annalaura; Dainese, Enrico

2016-01-01

Understanding the correct interaction among the different components of the endocannabinoid system (ECS) is fundamental for a proper assessment of the function of endocannabinoids (eCBs) as signaling molecules. The knowledge of how membrane environment is able to modulate intracellular trafficking of eCBs and their interacting proteins holds a huge potential in unraveling new mechanisms of ECS modulation.Here, fluorescence resonance energy transfer (FRET) technique is applied to measure the binding affinity of ECS proteins to model membranes (i.e., large unilamellar vesicles, LUVs). In particular, we describe in details the paradigmatic example of the interaction of recombinant rat FAAH-ΔTM with LUVs constituted by 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC).

Fostering public cord blood banking and research in Canada.

PubMed

Isasi, Rosario; Dalpe, Gratien; Knoppers, Bartha M

2013-12-01

In June 2013, Canadian Blood Services (CBS) established the National Public Cord Blood Bank (NPCBB) accessible to Canadian and international patients and researchers. The NPCBB promotes efforts that contribute to research and improved clinical care by making units not suitable for banking or transplantation available for research. In the context of the NPCBB of the CBS, this article will focus on the practical tools (e.g., consent protocols) developed to optimize umbilical cord blood (UCB) banking and research while enabling ethical provenance of UCB stem cells. The Canadian approach represents an ideal model for comparison as it is a country in which the national public bank (and other regional/provincial public banks) coexists with private companies.

Interaction mechanism of double bubbles in hydrodynamic cavitation

NASA Astrophysics Data System (ADS)

Li, Fengchao; Cai, Jun; Huai, Xiulan; Liu, Bin

2013-06-01

Bubble-bubble interaction is an important factor in cavitation bubble dynamics. In this paper, the dynamic behaviors of double cavitation bubbles driven by varying pressure field downstream of an orifice plate in hydrodynamic cavitation reactor are examined. The bubble-bubble interaction between two bubbles with different radii is considered. We have shown the different dynamic behaviors between double cavitation bubbles and a single bubble by solving two coupling nonlinear equations using the Runge-Kutta fourth order method with adaptive step size control. The simulation results indicate that, when considering the role of the neighbor smaller bubble, the oscillation of the bigger bubble gradually exhibits a lag in comparison with the single-bubble case, and the extent of the lag becomes much more obvious as time goes by. This phenomenon is more easily observed with the increase of the initial radius of the smaller bubble. In comparison with the single-bubble case, the oscillation of the bigger bubble is enhanced by the neighbor smaller bubble. Especially, the pressure pulse of the bigger bubble rises intensely when the sizes of two bubbles approach, and a series of peak values for different initial radii are acquired when the initial radius ratio of two bubbles is in the range of 0.9˜1.0. Although the increase of the center distance between two bubbles can weaken the mutual interaction, it has no significant influence on the enhancement trend. On the one hand, the interaction between two bubbles with different radii can suppress the growth of the smaller bubble; on the other hand, it also can enhance the growth of the bigger one at the same time. The significant enhancement effect due to the interaction of multi-bubbles should be paid more attention because it can be used to reinforce the cavitation intensity for various potential applications in future.

Visualization of airflow growing soap bubbles

NASA Astrophysics Data System (ADS)

Al Rahbi, Hamood; Bock, Matthew; Ryu, Sangjin

2016-11-01

Visualizing airflow inside growing soap bubbles can answer questions regarding the fluid dynamics of soap bubble blowing, which is a model system for flows with a gas-liquid-gas interface. Also, understanding the soap bubble blowing process is practical because it can contribute to controlling industrial processes similar to soap bubble blowing. In this study, we visualized airflow which grows soap bubbles using the smoke wire technique to understand how airflow blows soap bubbles. The soap bubble blower setup was built to mimic the human blowing process of soap bubbles, which consists of a blower, a nozzle and a bubble ring. The smoke wire was placed between the nozzle and the bubble ring, and smoke-visualized airflow was captured using a high speed camera. Our visualization shows how air jet flows into the growing soap bubble on the ring and how the airflow interacts with the soap film of growing bubble.

Effects of B2O3 content and sintering temperature on crystallization and microstructure of CBS glass-ceramic coatings

NASA Astrophysics Data System (ADS)

Li, Pengyang; Wang, Shubin; Liu, Jianggao; Feng, Mengjie; Yang, Xinwang

2015-11-01

Borosilicate glass-ceramics precursors with varying compositional ratios in the CaO-SiO2-B2O3 (CBS) system were synthesized by sol-gel method. The precursors were calcined at 1200 °C for 2 h to form glass powders. The glass-ceramics were prepared by overlaying glass slurries on the substrates before sintering at different temperatures. The as-prepared glasses and glass-ceramics were characterized by differential scanning calorimetry and X-ray diffraction. The crystallization activation energies (Ec) were calculated using the Kissinger method from DSC results. The morphology and crystallization behavior of the glass-ceramics were monitored by scanning electron microscopy. Both glass transition and crystallization temperatures decreased, however, the metastable zone increased. The Ec values of CBS glasses and glass-ceramics were 254.1, 173.2 and 164.4 kJ/mol with increasing B2O3 content, whereas that of the calcined G3 glass was 104.9 kJ/mol. Finally, the coatings were prepared at a low temperature (700 °C). The crystals that grew on the surface of multilayer coatings demonstrated heterogeneous surface nucleation and crystallization after heat-treatment from 700 °C to 850 °C for 4 h.

Genetic characterization of strains of Saccharomyces uvarum from New Zealand wineries.

PubMed

Zhang, Hanyao; Richards, Keith D; Wilson, Sandra; Lee, Soon A; Sheehan, Hester; Roncoroni, Miguel; Gardner, Richard C

2015-04-01

We present a genetic characterization of 65 isolates of Saccharomyces uvarum isolated from wineries in New Zealand, along with the complete nucleotide sequence of a single sulfite-tolerant isolate. The genome of the New Zealand isolate averaged 99.85% nucleotide identity to CBS7001, the previously sequenced strain of S. uvarum. However, three genomic segments (37-87 kb) showed 10% nucleotide divergence from CBS7001 but 99% identity to Saccharomyces eubayanus. We conclude that these three segments appear to have been introgressed from that species. The nucleotide sequence of the internal transcribed spacer (ITS) region from other New Zealand isolates were also very similar to that of CBS7001, and hybrids showed complete genetic compatibility for some strains, with tetrads giving four viable progeny that showed 2:2 segregations of marker genes. Some strains showed high tolerance to sulfite, with genetic analysis indicating linkage of this trait to the transcription factor FZF1, but not to SSU1, the sulfite efflux pump that it regulates in order to confer sulfite tolerance in Saccharomyces cerevisiae. The fermentation characteristics of selected strains of S. uvarum showed exceptionally good cold fermentation characteristics, superior to the best commercially available strains of S. cerevisiae. Copyright © 2014 Elsevier Ltd. All rights reserved.

Functional Assessment of Region-Specific Neglect: Are There Differential Behavioural Consequences of Peripersonal versus Extrapersonal Neglect?

PubMed Central

Nijboer, T. C. W.; ten Brink, A. F.; Kouwenhoven, M.; Visser-Meily, J. M. A.

2014-01-01

Background. Region-specific types of neglect (peripersonal and extrapersonal) have been dissociated, yet, differential behavioural consequences are unknown. Objective. The aim of the current study was to investigate behavioural consequences at the level of basic activities of daily living of region-specific neglect, using the Catherine Bergego Scale (CBS). Methods. 118 stroke patients were screened within the first two weeks after admission to the rehabilitation center for inpatient rehabilitation. Results. Patients with peripersonal neglect and patients with neglect for both regions had significantly higher total score on the CBS compared to nonneglect patients. Total scores for patients with extrapersonal neglect were comparable to non-neglect patients. ADL impairments were found across activities (e.g., looking towards one side, forgetting body parts, colliding) for both patients with peripersonal neglect and patients with neglect for both regions. Patients with extrapersonal neglect were only impaired on the item on way finding. Conclusions. When diagnosing neglect, it is relevant to distinguish the type of region-specific neglect and, where needed, to adjust the rehabilitation program accordingly. As the CBS is not developed to typically measure ADL in extrapersonal neglect, it would be of importance to add other (instrumental) activities that heavily rely on processing information in farther space. PMID:24825959

The Neuroglial Dialog Between Cannabinoids and Hemichannels

PubMed Central

Labra, Valeria C.; Santibáñez, Cristian A.; Gajardo-Gómez, Rosario; Díaz, Esteban F.; Gómez, Gonzalo I.; Orellana, Juan A.

2018-01-01

The formation of gap junctions was initially thought to be the central role of connexins, however, recent evidence had brought to light the high relevance of unopposed hemichannels as an independent mechanism for the selective release of biomolecules during physiological and pathological conditions. In the healthy brain, the physiological opening of astrocyte hemichannels modulates basal excitatory synaptic transmission. At the other end, the release of potentially neurotoxic compounds through astroglial hemichannels and pannexons has been insinuated as one of the functional alterations that negatively affect the progression of multiple brain diseases. Recent insights in this matter have suggested encannabinoids (eCBs) as molecules that could regulate the opening of these channels during diverse conditions. In this review, we discuss and hypothesize the possible interplay between the eCB system and the hemichannel/pannexon-mediated signaling in the inflamed brain and during event of synaptic plasticity. Most findings indicate that eCBs seem to counteract the activation of major neuroinflammatory pathways that lead to glia-mediated production of TNF-α and IL-1β, both well-known triggers of astroglial hemichannel opening. In contrast to the latter, in the normal brain, eCBs apparently elicit the Ca2+-activation of astrocyte hemichannels, which could have significant consequences on eCB-dependent synaptic plasticity. PMID:29662436

The texture, sensory properties and stability of cookies prepared with wax oleogels.

PubMed

Yılmaz, Emin; Öğütcü, Mustafa

2015-04-01

Shortening is the essential component of high quality baked foods. Its effects on dough structure formation and the desired final product attributes depend mostly on its solid fat content and β' crystalline polymorphs. Saturated and trans fatty acids present in shortening pose some important negative health considerations. Hence, alternative plastic fats with lower or zero quantity of saturated and trans fatty acids are in high demand. Oleogels are gel networks of liquid edible oils with no trans and very low saturated fatty acids. In this study, sunflower wax (SW) and beeswax (BW) oleogels of hazelnut oil were used in cookie preparation against commercial bakery shortening (CBS) as the control, to compare the textural, sensory and stability properties of the cookies. The basic chemical composition, textural properties, and some physical attributes of the cookies were compared. Sensory texture/flavor profile analysis (T/FPA) and consumer hedonic tests were also accomplished. Furthermore, the changes in cookie texture and stability were monitored during 30 day storage at room temperature. It was found out that in almost all properties, the oleogel cookies resembled CBS cookies. T/FPA results present detailed data for literature. Consumer hedonic scores indicated that oleogel cookies were better than CBS cookies and were also well accepted by consumers. Wax oleogels can be used as cookie shortening successfully.

The electronic and transport properties of monolayer transition metal dichalcogenides: a complex band structure analysis

NASA Astrophysics Data System (ADS)

Szczesniak, Dominik

Recently, monolayer transition metal dichalcogenides have attracted much attention due to their potential use in both nano- and opto-electronics. In such applications, the electronic and transport properties of group-VIB transition metal dichalcogenides (MX2 , where M=Mo, W; X=S, Se, Te) are particularly important. Herein, new insight into these properties is presented by studying the complex band structures (CBS's) of MX2 monolayers while accounting for spin-orbit coupling effects. By using the symmetry-based tight-binding model a nonlinear generalized eigenvalue problem for CBS's is obtained. An efficient method for solving such class of problems is presented and gives a complete set of physically relevant solutions. Next, these solutions are characterized and classified into propagating and evanescent states, where the latter states present not only monotonic but also oscillatory decay character. It is observed that some of the oscillatory evanescent states create characteristic complex loops at the direct band gaps, which describe the tunneling currents in the MX2 materials. The importance of CBS's and tunneling currents is demonstrated by the analysis of the quantum transport across MX2 monolayers within phase field matching theory. Present work has been prepared within the Qatar Energy and Environment Research Institute (QEERI) grand challenge ATHLOC project (Project No. QEERI- GC-3008).

World distribution of the T833C/844INS68 CBS in cis double mutation: a reliable anthropological marker.

PubMed

Pepe, G; Vanegas, O C; Rickards, O; Giusti, B; Comeglio, P; Brunelli, T; Marcucci, R; Prisco, D; Gensini, G F; Abbate, R

1999-02-01

Mild hyperhomocysteinemia is associated to mutations either in cystathionine beta-synthase (CBS) or in 5,10-methylenetetrahydrofolate reductase (MTHFR) genes. In 1995, Sebastio et al. characterized a 68 bp insertion in cis with the most common CBS mutation (T833C) detected in homocystinuric patients. Recently, this double mutation has been detected in Italian and North-American controls. Compared to a group of patients affected by coronary artery disease, North-American controls showed not statistically significant difference. Moreover, Italian controls displayed a microheterogeneity in the mutant allele frequency distribution depending on their geographical origin (North or South of Italy). Aim of our study was to evaluate the prevalence of the double in cis mutation in different populations. We studied 377 healthy subjects belonging to various human groups. Genomic DNA, extracted from peripheral blood samples, was amplified using specific primers; PCR fragments were digested with Bsr I restriction enzyme to detect the double mutation. Our data show a significant heterogeneity among the populations studied, therefore this mutation turned out to be a reliable anthropogenetic marker. The distribution of the double mutation will contribute, with other DNA polymorphisms, to evaluate the genetic admixture of mixed populations such as Afro-Americans.

Ultrastructural and chemotaxonomic analysis of a xylanolytic strain of Cryptococcus adeliensis isolated from sheep droppings in Spain.

PubMed

Velázquez, Encarna; del Villar, María; Grondona, Isabel; Monte, Enrique; González-Villa, Tomás

2006-09-01

Cryptococcus adeliensis was initially described as a psycrophilic species containing a single strain CBS 8351(T) isolated from decayed algae in Terre Adelie (Antartida). Later, a second strain of this species was isolated from an immunosuppressed patient affected by leukaemia in Germany and recently several strains from this species have been found in human patients and pigeon droppings of the same country. In this study, we isolated from sheep droppings in Spain a xylanolytic strain named LEVX01 that was phenotypically related to the strain CBS 8351(T) and showed a 100% similarity in the D1/D2 domain and 5.8S-ITS region sequences with respect to the remaining described strains of C. adeliensis. These findings suggest that this species has a wide geographical distribution and that the animal faeces are a common habitat for C. adeliensis. The chemotaxonomic analyses showed the absence of detectable amounts of xylose in the cell walls of the strains LEVX01 and CBS8351(T) in contrast to other Cryptococcus species. Interestingly, the ultrastructural study showed the presence of fimbriae in these two strains that could be involved in the attachment to the host cells and, as occurs in Candida albicans, they could also be a pathogenicity factor for the man.

Improved oil-off survivability of tapered roller bearings

NASA Technical Reports Server (NTRS)

Kreider, Gary E.; Lee, Peter W.

1987-01-01

The aim of this program is to improve the oil-off survivability of a tapered roller bearing when applied to a helicopter transmission, since the tapered bearing has shown a performance advantage in this application. However, the critical roller end-rib conjunction is vulnerable to damage in an oil-off condition. Three powdered metal materials were selected to use as the rib material for oil-off evaluation. These were: M2 steel to a 65% density, CBS 1000M 65% density, and CBS 1000M 75% density. The bearing styles tested were ribbed cone (inner race) and ribbed cup (outer race). Carburized solid CBS 600 was also used as a ribbed material for comparison of oil-off results. The tests were conducted at six speeds from 4000 rpm (0.26 million DN) through 37000 rpm (2.4 million DN).The ribbed cup style bearing achieved longer lives than the ribbed cone style. A standard bearing lasted only 10 minutes at 4000 rpm; however, the 30-min oil-off goal was achieved through 11000 rpm using the survivable ribbed cup bearing. The oil-off lives at 37000 rpm were less than 10 seconds. The grinding of the powder metal materials and surface preparation to achieve an open porosity is extremely critical to the oil-off performance of the powder metal component.

Double bubble with the big-bubble technique during deep anterior lamellar keratoplasty.

PubMed

Wise, Stephanie; Dubord, Paul; Yeung, Sonia N

2017-04-28

To report a case of intraoperative double bubble that formed during big-bubble DALK surgery in a patient with corneal scarring secondary to herpetic stromal keratitis. Case report. A 22 year old woman presented with a large corneal scar, likely secondary to previous herpetic stromal keratitis. She underwent big-bubble DALK surgery for visual rehabilitation. Intraoperatively, a mixed bubble with persistent type 2 bubble postoperatively was noted. The second bubble resorbed with clearance of the graft and good visual outcome after 6 weeks. This case report describes the unusual development of a mixed bubble during big-bubble DALK surgery. This graft cleared with resolution of the second bubble postoperatively without further surgical intervention.

Experimental study on bubble dynamics and wall heat transfer arising from a single nucleation site at subcooled flow boiling conditions – Part 2: Data analysis on sliding bubble characteristics and associated wall heat transfer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yooa, Junsoo; Estrada-Perez, Carlos E.; Hassan, Yassin A.

In this second of two companion papers presents an analysis of sliding bubble and wall heat transfer parameters measured during subcooled boiling in a square, vertical, upward flow channel. Bubbles were generated only from a single nucleation site for better observation of both the sliding bubbles’ characteristics and their impact on wall heat transfer through optical measurement techniques. Specific interests include: (i) bubbles departure and subsequent growth while sliding, (ii) bubbles release frequency, (iii) coalescence of sliding bubbles, (iv) sliding bubbles velocity, (v) bubbles size distribution and (vi) wall heat transfer influenced by sliding bubbles. Our results showed that slidingmore » bubbles involve two distinct growth behaviors: (i) at low mass fluxes, sliding bubbles grew fast near the nucleation site, subsequently shrank, and then grew again, (ii) as mass flux increased, however, sliding bubbles grew more steadily. The bubbles originating from the single nucleation site coalesced frequently while sliding, which showed close relation with bubbles release frequency. The sliding bubble velocity near the nucleation site consistently decreased by increasing mass flux, while the observation often became reversed as the bubbles slid downstream due to the effect of interfacial drag. The sliding bubbles moved faster than the local liquid (i.e., ur<0) at low mass flux conditions, but it became reversed as the mass flux increased. The size distribution of sliding bubbles followed Gaussian distribution well both near and far from the nucleation site. The standard deviation of bubble size varied insignificantly through sliding compared to the changes in mean bubble size. Lastly, the sliding bubbles enhanced the wall heat transfer and the effect became more noticeable as inlet subcooling/mass flux decreased or wall heat flux increased. Particularly, the sliding bubble characteristics such as bubble growth behavior observed near the nucleation site played a dominant role in determining the ultimate level of wall heat transfer enhancement within the test channel.« less

Experimental study on bubble dynamics and wall heat transfer arising from a single nucleation site at subcooled flow boiling conditions – Part 2: Data analysis on sliding bubble characteristics and associated wall heat transfer

DOE PAGES

Yooa, Junsoo; Estrada-Perez, Carlos E.; Hassan, Yassin A.

2016-04-28

In this second of two companion papers presents an analysis of sliding bubble and wall heat transfer parameters measured during subcooled boiling in a square, vertical, upward flow channel. Bubbles were generated only from a single nucleation site for better observation of both the sliding bubbles’ characteristics and their impact on wall heat transfer through optical measurement techniques. Specific interests include: (i) bubbles departure and subsequent growth while sliding, (ii) bubbles release frequency, (iii) coalescence of sliding bubbles, (iv) sliding bubbles velocity, (v) bubbles size distribution and (vi) wall heat transfer influenced by sliding bubbles. Our results showed that slidingmore » bubbles involve two distinct growth behaviors: (i) at low mass fluxes, sliding bubbles grew fast near the nucleation site, subsequently shrank, and then grew again, (ii) as mass flux increased, however, sliding bubbles grew more steadily. The bubbles originating from the single nucleation site coalesced frequently while sliding, which showed close relation with bubbles release frequency. The sliding bubble velocity near the nucleation site consistently decreased by increasing mass flux, while the observation often became reversed as the bubbles slid downstream due to the effect of interfacial drag. The sliding bubbles moved faster than the local liquid (i.e., ur<0) at low mass flux conditions, but it became reversed as the mass flux increased. The size distribution of sliding bubbles followed Gaussian distribution well both near and far from the nucleation site. The standard deviation of bubble size varied insignificantly through sliding compared to the changes in mean bubble size. Lastly, the sliding bubbles enhanced the wall heat transfer and the effect became more noticeable as inlet subcooling/mass flux decreased or wall heat flux increased. Particularly, the sliding bubble characteristics such as bubble growth behavior observed near the nucleation site played a dominant role in determining the ultimate level of wall heat transfer enhancement within the test channel.« less

Estimation of community-level influenza-associated illness in a low resource rural setting in India.

PubMed

Saha, Siddhartha; Gupta, Vivek; Dawood, Fatimah S; Broor, Shobha; Lafond, Kathryn E; Chadha, Mandeep S; Rai, Sanjay K; Krishnan, Anand

2018-01-01

To estimate rates of community-level influenza-like-illness (ILI) and influenza-associated ILI in rural north India. During 2011, we conducted household-based healthcare utilization surveys (HUS) for any acute medical illness (AMI) in preceding 14days among residents of 28villages of Ballabgarh, in north India. Concurrently, we conducted clinic-based surveillance (CBS) in the area for AMI episodes with illness onset ≤3days and collected nasal and throat swabs for influenza virus testing using real-time polymerase chain reaction. Retrospectively, we applied ILI case definition (measured/reported fever and cough) to HUS and CBS data. We attributed 14days of risk-time per person surveyed in HUS and estimated community ILI rate by dividing the number of ILI cases in HUS by total risk-time. We used CBS data on influenza positivity and applied it to HUS-based community ILI rates by age, month, and clinic type, to estimate the community influenza-associated ILI rates. The HUS of 69,369 residents during the year generated risk-time of 3945 person-years (p-y) and identified 150 (5%, 95%CI: 4-6) ILI episodes (38 ILI episodes/1,000 p-y; 95% CI 32-44). Among 1,372 ILI cases enrolled from clinics, 126 (9%; 95% CI 8-11) had laboratory-confirmed influenza (A (H3N2) = 72; B = 54). After adjusting for age, month, and clinic type, overall influenza-associated ILI rate was 4.8/1,000 p-y; rates were highest among children <5 years (13; 95% CI: 4-29) and persons≥60 years (11; 95%CI: 2-30). We present a novel way to use HUS and CBS data to generate estimates of community burden of influenza. Although the confidence intervals overlapped considerably, higher point estimates for burden among young children and older adults shows the utility for exploring the value of influenza vaccination among target groups.

Effects of methionine supplementation on the expression of oxidative stress-related genes in acute heat stress-exposed broilers.

PubMed

Del Vesco, Ana Paula; Gasparino, Eliane; Grieser, Daiane de Oliveira; Zancanela, Vittor; Soares, Maria Amélia Menck; Neto, Adhemar Rodrigues de Oliveira

2015-02-28

The aim of the present study was to evaluate the effects of heat stress (HS) and methionine supplementation on the markers of stress and on the gene expression levels of uncoupling proteins (UCP), betaine-homocysteine methyltransferase (BHMT), cystathionine β-synthase (CBS), glutathione synthetase (GSS) and glutathione peroxidase 7 (GPx7). Broilers from 1 to 21 d and from 22 to 42 d of age were divided into three treatment groups related to methionine supplementation: without methionine supplementation (MD); recommended level of methionine supplementation (DL1); excess methionine supplementation (DL2). The broilers were either kept at a comfortable thermal temperature or exposed to HS (38°C for 24 h). During the starter period, we observed the effects of the interaction between diet and environment on the gene expression levels of UCP, BHMT and GSS. Higher gene expression levels of UCP and BHMT were observed in broilers that were maintained at thermal comfort conditions and received the MD diet. HS broilers fed the DL1 and DL2 diets had the highest expression level of GSS. The expression levels of the CBS and GPx7 genes were influenced by both the environment and methionine supplementation. During the grower period, the gene expression levels of BHMT, CBS, GSS and GPx7 were affected by the diet × environment interaction. A higher expression level of BHMT was observed in broilers maintained at thermal comfort conditions and on the MD diet. HS induced higher expression levels of CBS, GSS and GPx7 in broilers that received the DL1 and DL2 diets. The present results suggest that under HS conditions, methionine supplementation could mitigate the effects of stress, since methionine contributed to the increased expression levels of genes related to antioxidant activity.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eriguchi, Takahisa; Takeda, Atsuya; Sanuki, Naoko

Purpose: To evaluate biliary toxicity after stereotactic body radiation therapy (SBRT) for liver tumors. Methods and Materials: Among 297 consecutive patients with liver tumors treated with SBRT of 35 to 50 Gy in 5 fractions, patients who were irradiated with >20 Gy to the central biliary system (CBS), including the gallbladder, and had follow-up times >6 months were retrospectively analyzed. Toxicity profiles, such as clinical symptoms and laboratory and radiologic data especially for obstructive jaundice and biliary infection, were investigated in relation to the dose volume and length relationship for each biliary organ. Results: Fifty patients with 55 tumors weremore » irradiated with >20 Gy to the CBS. The median follow-up period was 18.2 months (range, 6.0-80.5 months). In the dose length analysis, 39, 34, 14, and 2 patients were irradiated with >20 Gy, >30 Gy, >40 Gy, and >50 Gy, respectively, to >1 cm of the biliary tract. Seven patients were irradiated with >20 Gy to >20% of the gallbladder. Only 2 patients experienced asymptomatic bile duct stenosis. One patient, metachronously treated twice with SBRT for tumors adjacent to each other, had a transient increase in hepatic and biliary enzymes 12 months after the second treatment. The high-dose area >80 Gy corresponded to the biliary stenosis region. The other patient experienced biliary stenosis 5 months after SBRT and had no laboratory changes. The biliary tract irradiated with >20 Gy was 7 mm and did not correspond to the bile duct stenosis region. No obstructive jaundice or biliary infection was found in any patient. Conclusions: SBRT for liver tumors adjacent to the CBS was feasible with minimal biliary toxicity. Only 1 patient had exceptional radiation-induced bile duct stenosis. For liver tumors adjacent to the CBS without other effective treatment options, SBRT at a dose of 40 Gy in 5 fractions is a safe treatment with regard to biliary toxicity.« less

Heat inactivation of wine spoilage yeast Dekkera bruxellensis by hot water treatment.

PubMed

Fabrizio, V; Vigentini, I; Parisi, N; Picozzi, C; Compagno, C; Foschino, R

2015-08-01

Cell suspensions of four Dekkera bruxellensis strains (CBS 2499, CBS 2797, CBS 4459 and CBS 4601) were subjected to heat treatment in deionized water at four different temperatures (55·0, 57·5, 60·0 and 62·5°C) to investigate their thermal resistance. The decimal reduction times at a specific temperature were calculated from the resulting inactivation curves: the D-values at 55·0°C ranged from 63 to 79·4 s, at 57·5°C from 39·6 to 46·1 s, at 60·0°C from 19·5 to 20·7 s, at 62·5°C from 10·2 to 13·7 s. The z-values were between 9·2 and 10·2°C, confirming that heat resistance is a strain-dependent character. A protocol for the sanitization of 225 l casks by immersion in hot water was set up and applied to contaminated 3-year-old barrels. The heat penetration through the staves was evaluated for each investigated temperature by positioning a thermal probe at 8 mm deep. A treatment at 60°C for an exposure time of 19 min allowed to eliminate the yeast populations up to a log count reduction of 8. Brettanomyces/Dekkera bruxellensis is the main yeast involved in red wine spoilage that occurs during ageing in barrel, generating considerable economic losses. Current sanitization protocols, performed using different chemicals, are ineffective due to the porous nature of the wood. The thermal inactivation of D. bruxellensis cells by hot water treatment proves to be efficacious and easy to perform, provided that the holding time at the killing temperature takes into account the filling time of the vessel and the time for the heat penetration into the wood structure. © 2015 The Society for Applied Microbiology.

Relationship of the MTHFD1 (rs2236225), eNOS (rs1799983), CBS (rs2850144) and ACE (rs4343) gene polymorphisms in a population of Iranian pediatric patients with congenital heart defects.

PubMed

Khatami, Mehri; Ratki, Farzaneh Morteza; Tajfar, Saba; Akrami, Fatemeh

2017-09-01

Congenital heart defects are structural cardiovascular malformations that arise from abnormal formation of the heart or major blood vessels during the fetal period. To investigate the association of 4 single nucleotide polymorphisms (SNPs) in the MTHFD1, eNOS, CBS and ACE genes, we evaluated their relationship with CHD in Iranian patients. In this case-control study, a total of 102 children with CHD and 98 control children were enrolled. Four SNPs including MTHFD1 G1958A, eNOS G894T, CBS C-4673G and ACE A2350G were genotyped by PCR-SSCP, Multiplex ARMS PCR and PCR-RFLP methods and confirmed by direct sequencing. We genotyped 102 patients and 98 controls for four polymorphisms by statistically analysis. There were three SNPs including MTHFD1 G1958A, eNOS G894T and ACE A2350G which might increase the risk of CHD, but CBS C-4673G was not significantly different between patients and controls. (P = 0.017, P = 0.048, P = 0.025 and P = 0.081 respectively). The allele frequencies of three SNPs for MTHFD1 G1958A, eNOS G894T and ACE A2350G in CHD are higher than that in control. Our results show that there is a significant relationship between MTHFD1 G1958A, eNOS G894T and ACE A2350G polymorphisms with CHD. Therefore, The AA and GA genotypes of MTHFD1 G1958A, TT and GT genotypes of eNOS G894T and the AA and GA genotypes of ACE A2350G are susceptible factors for CHD and may increase the risk of CHD. Copyright © 2017. Published by Elsevier Taiwan.

Molecular characterization of twelve patients affected by homocystinuria due to cystathionine beta-synthase deficiency: Report of two novel mutations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sebastio, G.; Sperandeo, M.P.; Panico, M.

1994-09-01

Cystathionine beta-synthase (CBS) deficiency, an autosomal recessive disorder of sulfur amino acid metabolism (MIM 236200), causes homocystinuria and a clinical presentation involving eye, skeleton, central nervous and vascular systems. Less that 20 mutations of CBS gene have been characterized so far, G919A and T833C being the most commonly reported (36 and 9 out of 62 identified alleles, respectively). We have investigated 12 patients (10 Italians, 1 Jewish-French, 1 Italian-Spanish) and one allele of each patient has been characterized at least. T833C has been found in 7 independent alleles (6 in heterozygosity and 1 in homozygosity); G9191A, the most common mutationmore » in Irish and North-European patients, has never been detected in the present survey. C341T (previously reported in 1 Irish-German patient only) has been found in 3 patients in heterozygosity. Besides the two new mutations previously described, i.e. G374A and C770T, we have identified two additional new missense mutations: C869T, a transition in exon 8, causing a P290L amino acid substitution, and C262T, a transition in exon 2, causing a P88S amino acid change. In 4 additional Italian patients, none of the known mutations have been detected; in one of them, a 50 bp deletion has been found in intron 11. The deletion involves the entire sequence of the second element of a tandem repeat. Conclusions: T833C is the most common panethnic mutation; C341T is relatively widespread, while G919A appears to be restricted to North-European patients. Exons 3 and 8 of the CBS gene are the hot-spots of mutational events leading to CBS deficiency.« less

Gain and Bandwidth Enhancement of Ferrite-Loaded CBS Antenna Using Material Shaping and Positioning

NASA Astrophysics Data System (ADS)

Askarian Amiri, Mikal

Loading a cavity-backed slot (CBS) antenna with ferrite material and applying a biasing static magnetic field can be used to control its resonant frequency. Such a mechanism results in a frequency reconfigurable antenna. However, placing a lossy ferrite material inside the cavity can reduce the gain or negatively impact the impedance bandwidth. This thesis develops guidelines, based on a non-uniform applied magnetic field and non-uniform magnetic field internal to the ferrite specimen, for the design of ferrite-loaded CBS antennas which enhance their gain and tunable bandwidth by shaping the ferrite specimen and judiciously locating it within the cavity. To achieve these objectives, it is necessary to examine the influence of the shape and relative location of the ferrite material, and also the proximity of the ferrite specimen from the probe on the DC magnetic field and RF electric field distributions inside the cavity. The geometry of the probe and its impacts on figures-of-merit of the antenna is of interest as well. Two common cavity backed-slot antennas (rectangular and circular cross-section) were designed, and corresponding simulations and measurements were performed and compared. The cavities were mounted on 30 cm × 30 cm perfect electric conductor (PEC) ground planes and partially loaded with ferrite material. The ferrites were biased with an external magnetic field produced by either an electromagnet or permanent magnets. Simulations were performed using FEM-based commercial software, Ansys' Maxwell 3D and HFSS. Maxwell 3D is utilized to model the non-uniform DC applied magnetic field and non-uniform magnetic field internal to the ferrite specimen; HFSS however, is used to simulate and obtain the RF characteristics of the antenna. To validate the simulations they were compared with measurements performed in ASU's EM Anechoic Chamber. After many examinations using simulations and measurements, some optimal designs guidelines with respect to the gain, return loss and tunable impedance bandwidth, were obtained and recommended for ferrite-loaded CBS antennas.

Culture-Bound Syndromes of a Brazilian Amazon Riverine population: Tentative correspondence between traditional and conventional medicine terms and possible ethnopharmacological implications.

PubMed

Pagani, E; Santos, J de F L; Rodrigues, E

2017-05-05

It is not always possible to correlate the "emic" terms to the "etic" ones during ethnopharmacological surveys, especially regarding those related to Culture-Bound Syndromes (CBS). Nevertheless, it is the role of ethnopharmacology to address these correlations, since they are the basis for the understanding of potential bioactives. This study reports the clinical manifestations and therapeutic resources used for the treatment of CBS among some riverine inhabitants of Brazilian Amazonia. An effort was made to establish a correspondence between the local "emic" terms of traditional medicine and the symptoms or diseases known by conventional medicine ("etic" terms). The ultimate goal was to gain insights to suggest further pharmacological studies with the local resources. Fieldwork was guided by methods of anthropology, botany and zoology-with the assistance of a doctor-among the traditional healing experts in Jaú National Park (during 199 days in 1995) and Unini River Extractive Reserve (210 days from 2008 to 2012). Fifty-nine healers of different kinds were interviewed: a prayer-maker, medium, natural resource expert, massage therapist, midwife and snakebite healer. The clinical manifestations and healing resources of the following CBS were collected: "mau olhado" (evil eye), "quebrante" (chipping); "espante" (fright or susto); "doença do ar" (air diseases); "vento caído" (fallen wind); "derrame" (leakage); "mãe do corpo" (mother of the body) and "panema" (unlucky). The first three seem to be local variations of other CBSs already described in Latin America. "doença do ar", "vento caído", "derrame" and "mãe do corpo" seem to be folk terms for known conventional medical disorders, while "panema" is a yet undescribed Brazilian CBS that is possibly related to dysthymic disorder or depression and deserves further investigation. Treatments included prayer rituals, fumigation, baths and oral remedies using 25 plants and 10 animals. It was possible to establish hypothetical correlations between CBS as described by the riverine population studied and some "etic" terms. The main importance of this is to help the proposition of target-oriented pharmacological studies of the natural resources used by these communities. Accordingly, the following plants are suggested to be submitted to further studies for antidepressant and anxiolytic activities: Siparuna guianensis, Mansoa alliacea, Leucas martinicensis, Petiveria alliacea, Annona montana and Alpinia nutans; for anti-seizure activity: Protium amazonicum, Protium aracouchini and Protium heptaphyllum; finally for antispasmodic activity: Leucas martinicensis. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Thermochemistry and electronic structure of small boron clusters (B(n), n = 5-13) and their anions.

PubMed

Truong, Ba Tai; Grant, Daniel J; Nguyen, Minh Tho; Dixon, David A

2010-01-21

Thermochemical parameters of a set of small-sized neutral (B(n)) and anionic (B(n)(-)) boron clusters, with n = 5-13, were determined using coupled-cluster theory CCSD(T) calculations with the aug-cc-pVnZ (n = D, T, and Q) basis sets extrapolated to the complete basis set limit (CBS) plus addition corrections and/or G3B3 calculations. Enthalpies of formation, adiabatic electron affinities (EA), vertical (VDE), and adiabatic (ADE) detachment energies were evaluated. Our calculated EAs are in good agreement with recent experiments (values in eV): B(5) (CBS, 2.29; G3B3, 2.48; exptl., 2.33 +/- 0.02), B(6) (CBS, 2.59; G3B3, 3.23; exptl., 3.01 +/- 0.04), B(7) (CBS, 2.62; G3B3, 2.67; exptl., 2.55 +/- 0.05), B(8) (CBS, 3.02; G3B3, 3.11; exptl., 3.02 +/- 0.02), B(9) (G3B3, 3.03; exptl., 3.39 +/- 0.06), B(10) (G3B3, 2.85; exptl., 2.88 +/- 0.09), B(11) (G3B4, 3.48;, exptl., 3.43 +/- 0.01), B(12) (G3B3, 2.33; exptl., 2.21 +/- 0.04), and B(13) (G3B3, 3.62; exptl., 3.78 +/- 0.02). The difference between the calculated adiabatic electron affinity and the adiabatic detachment energy for B(6) is due to the fact that the geometry of the anion is not that of the ground-state neutral. The calculated adiabatic detachment energies to the (3)A(u), C(2h) and (1)A(g), D(2h) excited states of B(6), which have geometries similar to the (1)A(g), D(2h) state of B(6)(-), are 2.93 and 3.06 eV, in excellent agreement with experiment. The VDEs were also well reproduced by the calculations. Partitioning of the electron localization functions into pi and sigma components allows probing of the partial and local delocalization in global nonaromatic systems. The larger clusters appear to exhibit multiple aromaticity. The binding energies per atom vary in a parallel manner for both neutral and anionic series and approach the experimental value for the heat of atomization of B. The resonance energies and the normalized resonance energies are convenient indices to quantify the stabilization of a cluster of elements.

Comparative genomics of citric-acid producing Aspergillus niger ATCC 1015 versus enzyme-producing CBS 513.88

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grigoriev, Igor V.; Baker, Scott E.; Andersen, Mikael R.

2011-04-28

The filamentous fungus Aspergillus niger exhibits great diversity in its phenotype. It is found globally, both as marine and terrestrial strains, produces both organic acids and hydrolytic enzymes in high amounts, and some isolates exhibit pathogenicity. Although the genome of an industrial enzyme-producing A. niger strain (CBS 513.88) has already been sequenced, the versatility and diversity of this species compels additional exploration. We therefore undertook whole genome sequencing of the acidogenic A. niger wild type strain (ATCC 1015), and produced a genome sequence of very high quality. Only 15 gaps are present in the sequence and half the telomeric regionsmore » have been elucidated. Moreover, sequence information from ATCC 1015 was utilized to improve the genome sequence of CBS 513.88. Chromosome-level comparisons uncovered several genome rearrangements, deletions, a clear case of strain-specific horizontal gene transfer, and identification of 0.8 megabase of novel sequence. Single nucleotide polymorphisms per kilobase (SNPs/kb) between the two strains were found to be exceptionally high (average: 7.8, maximum: 160 SNPs/kb). High variation within the species was confirmed with exo-metabolite profiling and phylogenetics. Detailed lists of alleles were generated, and genotypic differences were observed to accumulate in metabolic pathways essential to acid production and protein synthesis. A transcriptome analysis revealed up-regulation of the electron transport chain, specifically the alternative oxidative pathway in ATCC 1015, while CBS 513.88 showed significant up-regulation of genes relevant to glucoamylase A production, such as tRNA-synthases and protein transporters. Our results and datasets from this integrative systems biology analysis resulted in a snapshot of fungal evolution and will support further optimization of cell factories based on filamentous fungi.[Supplemental materials (10 figures, three text documents and 16 tables) have been made available. The whole genome sequence for A. niger ATCC 1015 is available from NBCI under acc. no ACJE00000000. The up-dated sequence for A. niger CBS 513.88 is available from EMBL under acc. no AM269948-AM270415. The sequence data from the phylogeny study has been submitted to NCBI (GU296686-296739). Microarray data from this study is submitted to GEO as series GSE10983. Accession for reviewers is possible through: http://www.ncbi.nlm.nih.gov/geo/query/acc.cgi token GSE10983] The dsmM_ANIGERa_coll511030F library and platform information is deposited at GEO under number GPL6758« less

Bubble dynamics and bubble-induced turbulence of a single-bubble chain

NASA Astrophysics Data System (ADS)

Lee, Joohyoung; Park, Hyungmin

2016-11-01

In the present study, the bubble dynamics and liquid-phase turbulence induced by a chain of bubbles injected from a single nozzle have been experimentally investigated. Using a high-speed two-phase particle image velociemtry, measurements on the bubbles and liquid-phase velocity field are conducted in a transparent tank filled with water, while varying the bubble release frequency from 0.1 to 35 Hz. The tested bubble size ranges between 2.0-3.2 mm, and the corresponding bubble Reynolds number is 590-1100, indicating that it belongs to the regime of path instability. As the release frequency increases, it is found that the global shape of bubble dispersion can be classified into two regimes: from asymmetric (regular) to axisymmetric (irregular). In particular, at higher frequency, the wake vortices of leading bubbles cause an irregular behaviour of the following bubble. For the liquid phase, it is found that a specific trend on the bubble-induced turbulence appears in a strong relation to the above bubble dynamics. Considering this, we try to provide a theoretical model to estimate the liquid-phase turbulence induced by a chain of bubbles. Supported by a Grant funded by Samsung Electronics, Korea.

Gas Bubble Migration and Trapping in Porous Media: Pore-Scale Simulation

NASA Astrophysics Data System (ADS)

Mahabadi, Nariman; Zheng, Xianglei; Yun, Tae Sup; van Paassen, Leon; Jang, Jaewon

2018-02-01

Gas bubbles can be naturally generated or intentionally introduced in sediments. Gas bubble migration and trapping affect the rate of gas emission into the atmosphere or modify the sediment properties such as hydraulic and mechanical properties. In this study, the migration and trapping of gas bubbles are simulated using the pore-network model extracted from the 3D X-ray image of in situ sediment. Two types of bubble size distribution (mono-sized and distributed-sized cases) are used in the simulation. The spatial and statistical bubble size distribution, residual gas saturation, and hydraulic conductivity reduction due to the bubble trapping are investigated. The results show that the bubble size distribution becomes wider during the gas bubble migration due to bubble coalescence for both mono-sized and distributed-sized cases. And the trapped bubble fraction and the residual gas saturation increase as the bubble size increases. The hydraulic conductivity is reduced as a result of the gas bubble trapping. The reduction in hydraulic conductivity is apparently observed as bubble size and the number of nucleation points increase.

Nonspherical laser-induced cavitation bubbles

NASA Astrophysics Data System (ADS)

Lim, Kang Yuan; Quinto-Su, Pedro A.; Klaseboer, Evert; Khoo, Boo Cheong; Venugopalan, Vasan; Ohl, Claus-Dieter

2010-01-01

The generation of arbitrarily shaped nonspherical laser-induced cavitation bubbles is demonstrated with a optical technique. The nonspherical bubbles are formed using laser intensity patterns shaped by a spatial light modulator using linear absorption inside a liquid gap with a thickness of 40μm . In particular we demonstrate the dynamics of elliptic, toroidal, square, and V-shaped bubbles. The bubble dynamics is recorded with a high-speed camera at framing rates of up to 300000 frames per second. The observed bubble evolution is compared to predictions from an axisymmetric boundary element simulation which provides good qualitative agreement. Interesting dynamic features that are observed in both the experiment and simulation include the inversion of the major and minor axis for elliptical bubbles, the rotation of the shape for square bubbles, and the formation of a unidirectional jet for V-shaped bubbles. Further we demonstrate that specific bubble shapes can either be formed directly through the intensity distribution of a single laser focus, or indirectly using secondary bubbles that either confine the central bubble or coalesce with the main bubble. The former approach provides the ability to generate in principle any complex bubble geometry.

Aspherical bubble dynamics and oscillation times

DOE Office of Scientific and Technical Information (OSTI.GOV)

Godwin, R.P.; Chapyak, E.J.; Noack, J.

1999-03-01

The cavitation bubbles common in laser medicine are rarely perfectly spherical and are often located near tissue boundaries, in vessels, etc., which introduce aspherical dynamics. Here, novel features of aspherical bubble dynamics are explored. Time-resolved experimental photographs and simulations of large aspect ratio (length:diameter {approximately}20) cylindrical bubble dynamics are presented. The experiments and calculations exhibit similar dynamics. A small high-pressure cylindrical bubble initially expands radially with hardly any axial motion. Then, after reaching its maximum volume, a cylindrical bubble collapses along its long axis with relatively little radial motion. The growth-collapse period of these very aspherical bubbles differs only sightlymore » from twice the Rayleigh collapse time for a spherical bubble with an equivalent maximum volume. This fact justifies using the temporal interval between the acoustic signals emitted upon bubble creation and collapse to estimate the maximum bubble volume. As a result, hydrophone measurements can provide an estimate of the bubble energy even for aspherical bubbles. The prolongation of the oscillation period of bubbles near solid boundaries relative to that of isolated spherical bubbles is also discussed.« less

Extreme conditions in a dissolving air nanobubble

NASA Astrophysics Data System (ADS)

Yasui, Kyuichi; Tuziuti, Toru; Kanematsu, Wataru

2016-07-01

Numerical simulations of the dissolution of an air nanobubble in water have been performed taking into account the effect of bubble dynamics (inertia of the surrounding liquid). The presence of stable bulk nanobubbles is not assumed in the present study because the bubble radius inevitably passes the nanoscale in the complete dissolution of a bubble. The bubble surface is assumed to be clean because attachment of hydrophobic materials on the bubble surface could considerably change the gas diffusion rate. The speed of the bubble collapse (the bubble wall speed) increases to about 90 m/s or less. The shape of a bubble is kept nearly spherical because the amplitude of the nonspherical component of the bubble shape is negligible compared to the instantaneous bubble radius. In other words, a bubble never disintegrates into daughter bubbles during the dissolution. At the final moment of the dissolution, the temperature inside a bubble increases to about 3000 K due to the quasiadiabatic compression. The bubble temperature is higher than 1000 K only for the final 19 ps. However, the Knudsen number is more than 0.2 for this moment, and the error associated with the continuum model should be considerable. In the final 2.3 ns, only nitrogen molecules are present inside a bubble as the solubility of nitrogen is the lowest among the gas species. The radical formation inside a bubble is negligible because the probability of nitrogen dissociation is only on the order of 10-15. The pressure inside a bubble, as well as the liquid pressure at the bubble wall, increases to about 5 GPa at the final moment of dissolution. The pressure is higher than 1 GPa for the final 0.7 ns inside a bubble and for the final 0.6 ns in the liquid at the bubble wall. The liquid temperature at the bubble wall increases to about 360 K from 293 K at the final stage of the complete dissolution.

The dynamics of histotripsy bubbles

NASA Astrophysics Data System (ADS)

Kreider, Wayne; Bailey, Michael R.; Sapozhnikov, Oleg A.; Khokhlova, Vera A.; Crum, Lawrence A.

2011-09-01

Histotripsy describes treatments in which high-amplitude acoustic pulses are used to excite bubbles and erode tissue. Though tissue erosion can be directly attributed to bubble activity, the genesis and dynamics of bubbles remain unclear. Histotripsy lesions that show no signs of thermal coagulative damage have been generated with two different acoustic protocols: relatively long acoustic pulses that produce local boiling within milliseconds and relatively short pulses that are higher in amplitude but likely do not produce boiling. While these two approaches are often distinguished as `boiling' versus `cavitation', such labels can obscure similarities. In both cases, a bubble undergoes large changes in radius and vapor is transported into and out of the bubble as it oscillates. Moreover, observations from both approaches suggest that bubbles grow to a size at which they cease to collapse violently. In order to better understand the dynamics of histotripsy bubbles, a single-bubble model has been developed that couples acoustically excited bubble motions to the thermodynamic state of the surrounding liquid. Using this model for bubbles exposed to histotripsy sound fields, simulations suggest that two mechanisms can act separately or in concert to lead to the typically observed bubble growth. First, nonlinear acoustic propagation leads to the evolution of shocks and an asymmetry in the positive and negative pressures that drive bubble motion. This asymmetry can have a rectifying effect on bubble oscillations whereby the bubble grows on average during each acoustic cycle. Second, vapor transport to/from the bubble tends to produce larger bubbles, especially at elevated temperatures. Vapor transport by itself can lead to rectified bubble growth when the ambient temperature exceeds 100 °C (`boiling') or local heating in the vicinity of the bubble leads to a superheated boundary layer.

Vapor Bubbles

NASA Astrophysics Data System (ADS)

Prosperetti, Andrea

2017-01-01

This article reviews the fundamental physics of vapor bubbles in liquids. Work on bubble growth and condensation for stationary and translating bubbles is summarized and the differences with bubbles containing a permanent gas stressed. In particular, it is shown that the natural frequency of a vapor bubble is proportional not to the inverse radius, as for a gas bubble, but to the inverse radius raised to the power 2/3. Permanent gas dissolved in the liquid diffuses into the bubble with strong effects on its dynamics. The effects of the diffusion of heat and mass on the propagation of pressure waves in a vaporous bubbly liquid are discussed. Other topics briefly touched on include thermocapillary flow, plasmonic nanobubbles, and vapor bubbles in an immiscible liquid.

Anti-Bubbles

NASA Astrophysics Data System (ADS)

Tufaile, Alberto; Sartorelli, José Carlos

2003-08-01

An anti-bubble is a striking kind of bubble in liquid that seemingly does not comply the buoyancy, and after few minutes it disappears suddenly inside the liquid. Different from a simple air bubble that rises directly to the liquid surface, an anti-bubble wanders around in the fluid due to its slightly lesser density than the surrounding liquid. In spite of this odd behavior, an anti-bubble can be understood as the opposite of a conventional soap bubble in air, which is a shell of liquid surrounding air, and an anti-bubble is a shell of air surrounding a drop of the liquid inside the liquid. Two-phase flow has been a subject of interest due to its relevance to process equipment for contacting gases and liquids applied in industry. A chain of bubbles rising in a liquid formed from a nozzle is a two-phase flow, and there are certain conditions in which spherical air shells, called anti-bubbles, are produced. The purpose of this work is mainly to note the existence of anti-bubbling regime as a sequel of a bubbling system. We initially have presented the experimental apparatus. After this we have described the evolution of the bubbling regimes, and emulated the effect of bubbling coalescence with simple maps. Then is shown the inverted dripping as a consequence of the bubble coalescence, and finally the conditions for anti-bubble formation.

Candida laoshanensis sp. nov. and Candida qingdaonensis sp. nov., anamorphic, ascomycetous yeast species isolated from decayed wood.

PubMed

Wang, Shi-An; Li, Fu-Li; Bai, Feng-Yan

2010-07-01

During a study of newly isolated yeast strains utilizing d-xylose as sole carbon source, eight strains, isolated from decayed wood, were found to represent two novel anamorphic, ascomycetous yeast species based on sequence analysis of the 26S rDNA D1/D2 domain and internal transcribed spacer region, and phenotypic characterization. The names Candida laoshanensis sp. nov. (type strain MLRW 6-2(T)=AS 2.4030(T)=CBS 11389(T)) and Candida qingdaonensis sp. nov. (type strain MLRW 7-1(T)=AS 2.4031(T)=CBS 11390(T)) are proposed for these two novel species; the closest relatives of the two novel species are Candida pomicola and Candida marilandica, respectively.

An automated exploration of the isomerization and dissociation pathways of (E)-1,2-dichloroethene cations and anions

NASA Astrophysics Data System (ADS)

Kishimoto, Naoki; Nishi, Yuito

2017-04-01

Isomerization and dissociation pathways after the photoionization or electron attachment of (E)-1,2-dichloroethene were calculated with an automated exploration method utilizing a scaled hypersphere search of the anharmonic downward distortion following algorithm at the UB3LYP/6-311G(2d,d,p) level of theory. The potential energies of transition states and dissociation channels were calculated by a composite method ((RO)CBS-QB3) and compared with the breakdown diagrams and electron attachment spectra observed in previous spectroscopic studies. The results of single point calculations with several DFT and post-SCF methods are compared using the root mean square deviations from the (RO)CBS-QB3 energies for six states of anionic dichloroethene.

Applying the health belief model to examine news coverage regarding steroids in sports by ABC, CBS, and NBC between March 1990 and May 2008.

PubMed

Quick, Brian L

2010-04-01

The investigation described here examined ABC, CBS, and NBC news coverage of steroids in sports between March 1990 and May 2008. Employing a framing analysis guided by the health belief model (HBM), coverage of the barriers and benefits of using steroids is reported. Overall, the trend by these three news affiliates was to emphasize the illegality of using steroids, whereas considerably less coverage was devoted to the health costs, in terms of both severity and susceptibility, of using steroids. Furthermore, of the health costs reported, the specific consequences of steroid use varied considerably. The results are reported across four timeframes: 1990-2008, 1990-1996, 1997-2002, and 2003-2008.

Monte Carlo simulation of spectral reflectance and BRDF of the bubble layer in the upper ocean.

PubMed

Ma, Lanxin; Wang, Fuqiang; Wang, Chengan; Wang, Chengchao; Tan, Jianyu

2015-09-21

The presence of bubbles can significantly change the radiative properties of seawater and these changes will affect remote sensing and underwater target detection. In this work, the spectral reflectance and bidirectional reflectance characteristics of the bubble layer in the upper ocean are investigated using the Monte Carlo method. The Hall-Novarini (HN) bubble population model, which considers the effect of wind speed and depth on the bubble size distribution, is used. The scattering coefficients and the scattering phase functions of bubbles in seawater are calculated using Mie theory, and the inherent optical properties of seawater for wavelengths between 300 nm and 800 nm are related to chlorophyll concentration (Chl). The effects of bubble coating, Chl, and bubble number density on the spectral reflectance of the bubble layer are studied. The bidirectional reflectance distribution function (BRDF) of the bubble layer for both normal and oblique incidence is also investigated. The results show that bubble populations in clear waters under high wind speed conditions significantly influence the reflection characteristics of the bubble layer. Furthermore, the contribution of bubble populations to the reflection characteristics is mainly due to the strong backscattering of bubbles that are coated with an organic film.

Possible high sonic velocity due to the inclusion of gas bubbles in water

NASA Astrophysics Data System (ADS)

Banno, T.; Mikada, H.; Goto, T.; Takekawa, J.

2010-12-01

If formation water becomes multi-phase by inclusion of gas bubbles, sonic velocities would be strongly influenced. In general, sonic velocities are knocked down due to low bulk moduli of the gas bubbles. However, sonic velocities may increase depending on the size of gas bubbles, when the bubbles in water or other media oscillate due to incoming sonic waves. Sonic waves are scattered by the bubbles and the superposition of the incoming and the scattered waves result in resonant-frequency-dependent behavior. The phase velocity of sonic waves propagating in fluids containing bubbles, therefore, probably depends on their frequencies. This is a typical phenomenon called “wave dispersion.” So far we have studied about the bubble impact on sonic velocity in bubbly media, such as the formation that contains gas bubbles. As a result, it is shown that the bubble resonance effect is a key to analyze the sonic phase velocity increase. Therefore to evaluate the resonance frequency of bubbles is important to solve the frequency response of sonic velocity in formations having bubbly fluids. There are several analytical solutions of the resonance frequency of bubbles in water. Takahira et al. (1994) derived a equation that gives us the resonance frequency considering bubble - bubble interactions. We have used this theory to calculate resonance frequency of bubbles at the previous work. However, the analytical solution of the Takahira’s equation is based on several assumptions. Therefore we used a numerical approach to calculate the bubble resonance effect more precisely in the present study. We used the boundary element method (BEM) to reproduce a bubble oscillation in incompressible liquid. There are several reasons to apply the BEM. Firstly, it arrows us to model arbitrarily sets and shapes of bubbles. Secondly, it is easy to use the BEM to reproduce a boundary-surface between liquid and gas. The velocity potential of liquid surrounding a bubble satisfies the Laplace equation when the liquid is supposed to be incompressible. We got the boundary integral equation from the Laplace equation and solved the boundary integral equation by the BEM. Then, we got the gradient of the velocity potential from the BEM. We used this gradient to get time derivative of the velocity potential from the Bernouii’s equation. And we used the second order Adams-Bashforth method to execute time integration of the velocity potential. We conducted this scheme iteratively to calculate a bubble oscillation. At each time step, we input a pressure change as a sinusoidal wave. As a result, we observed a bubble oscillation following the pressure frequency. We also evaluated the resonance frequency of a bubble by changing the pressure frequency. It showed a good agreement with the analytical solution described above. Our future work is to extend the calculation into plural bubbles condition. We expect that interaction between bubbles becomes strong and resonance frequency of bubbles becomes small when distance between bubbles becomes small.

Bubbles in an acoustic field: an overview.

PubMed

Ashokkumar, Muthupandian; Lee, Judy; Kentish, Sandra; Grieser, Franz

2007-04-01

Acoustic cavitation is the fundamental process responsible for the initiation of most of the sonochemical reactions in liquids. Acoustic cavitation originates from the interaction between sound waves and bubbles. In an acoustic field, bubbles can undergo growth by rectified diffusion, bubble-bubble coalescence, bubble dissolution or bubble collapse leading to the generation of primary radicals and other secondary chemical reactions. Surface active solutes have been used in association with a number of experimental techniques in order to isolate and understand these activities. A strobe technique has been used for monitoring the growth of a single bubble by rectified diffusion. Multibubble sonoluminescence has been used for monitoring the growth of the bubbles as well as coalescence between bubbles. The extent of bubble coalescence has also been monitored using a newly developed capillary technique. An overview of the various experimental results has been presented in order to highlight the complexities involved in acoustic cavitation processes, which on the other hand arise from a simple, mechanical interaction between sound waves and bubbles.

Improvement of ore recovery efficiency in a flotation column cell using ultra-sonic enhanced bubbles

NASA Astrophysics Data System (ADS)

Filippov, L. O.; Royer, J. J.; Filippova, I. V.

2017-07-01

The ore process flotation technique is enhanced by using external ultra-sonic waves. Compared to the classical flotation method, the application of ultrasounds to flotation fluids generates micro-bubbles by hydrodynamic cavitation. Flotation performances increase was modelled as a result of increased probabilities of the particle-bubble attachment and reduced detachment probability under sonication. A simplified analytical Navier-Stokes model is used to predict the effect of ultrasonic waves on bubble behavior. If the theory is verified by experimentation, it predicts that the ultrasonic waves would create cavitation micro-bubbles, smaller than the flotation bubble added by the gas sparger. This effect leads to increasing the number of small bubbles in the liquid which promote particle-bubble attachment through coalescence between bubbles and micro-bubbles. The decrease in the radius of the flotation bubbles under external vibration forces has an additional effect by enhancing the bubble-particle collision. Preliminary results performed on a potash ore seem to confirm the theory.

Bubbles with shock waves and ultrasound: a review.

PubMed

Ohl, Siew-Wan; Klaseboer, Evert; Khoo, Boo Cheong

2015-10-06

The study of the interaction of bubbles with shock waves and ultrasound is sometimes termed 'acoustic cavitation'. It is of importance in many biomedical applications where sound waves are applied. The use of shock waves and ultrasound in medical treatments is appealing because of their non-invasiveness. In this review, we present a variety of acoustics-bubble interactions, with a focus on shock wave-bubble interaction and bubble cloud phenomena. The dynamics of a single spherically oscillating bubble is rather well understood. However, when there is a nearby surface, the bubble often collapses non-spherically with a high-speed jet. The direction of the jet depends on the 'resistance' of the boundary: the bubble jets towards a rigid boundary, splits up near an elastic boundary, and jets away from a free surface. The presence of a shock wave complicates the bubble dynamics further. We shall discuss both experimental studies using high-speed photography and numerical simulations involving shock wave-bubble interaction. In biomedical applications, instead of a single bubble, often clouds of bubbles appear (consisting of many individual bubbles). The dynamics of such a bubble cloud is even more complex. We shall show some of the phenomena observed in a high-intensity focused ultrasound (HIFU) field. The nonlinear nature of the sound field and the complex inter-bubble interaction in a cloud present challenges to a comprehensive understanding of the physics of the bubble cloud in HIFU. We conclude the article with some comments on the challenges ahead.

Bubbles with shock waves and ultrasound: a review

PubMed Central

Ohl, Siew-Wan; Klaseboer, Evert; Khoo, Boo Cheong

2015-01-01

The study of the interaction of bubbles with shock waves and ultrasound is sometimes termed ‘acoustic cavitation'. It is of importance in many biomedical applications where sound waves are applied. The use of shock waves and ultrasound in medical treatments is appealing because of their non-invasiveness. In this review, we present a variety of acoustics–bubble interactions, with a focus on shock wave–bubble interaction and bubble cloud phenomena. The dynamics of a single spherically oscillating bubble is rather well understood. However, when there is a nearby surface, the bubble often collapses non-spherically with a high-speed jet. The direction of the jet depends on the ‘resistance' of the boundary: the bubble jets towards a rigid boundary, splits up near an elastic boundary, and jets away from a free surface. The presence of a shock wave complicates the bubble dynamics further. We shall discuss both experimental studies using high-speed photography and numerical simulations involving shock wave–bubble interaction. In biomedical applications, instead of a single bubble, often clouds of bubbles appear (consisting of many individual bubbles). The dynamics of such a bubble cloud is even more complex. We shall show some of the phenomena observed in a high-intensity focused ultrasound (HIFU) field. The nonlinear nature of the sound field and the complex inter-bubble interaction in a cloud present challenges to a comprehensive understanding of the physics of the bubble cloud in HIFU. We conclude the article with some comments on the challenges ahead. PMID:26442143

Bubble dynamics in a standing sound field: the bubble habitat.

PubMed

Koch, P; Kurz, T; Parlitz, U; Lauterborn, W

2011-11-01

Bubble dynamics is investigated numerically with special emphasis on the static pressure and the positional stability of the bubble in a standing sound field. The bubble habitat, made up of not dissolving, positionally and spherically stable bubbles, is calculated in the parameter space of the bubble radius at rest and sound pressure amplitude for different sound field frequencies, static pressures, and gas concentrations of the liquid. The bubble habitat grows with static pressure and shrinks with sound field frequency. The range of diffusionally stable bubble oscillations, found at positive slopes of the habitat-diffusion border, can be increased substantially with static pressure.

How many bubbles in your glass of bubbly?

PubMed

Liger-Belair, Gérard

2014-03-20

The issue about how many carbon dioxide bubbles are likely to nucleate in a glass of champagne (or bubbly) is of concern for sommeliers, wine journalists, experienced tasters, and any open minded physical chemist wondering about complex phenomena at play in a glass of bubbly. The whole number of bubbles likely to form in a single glass is the result of the fine interplay between dissolved CO2, tiny gas pockets trapped within particles acting as bubble nucleation sites, and ascending bubble dynamics. Based on theoretical models combining ascending bubble dynamics and mass transfer equations, the falsely naı̈ve question of how many bubbles are likely to form per glass is discussed in the present work. A theoretical relationship is derived, which provides the whole number of bubbles likely to form per glass, depending on various parameters of both the wine and the glass itself.

Using a Novel Optical Sensor to Characterize Methane Ebullition Processes

NASA Astrophysics Data System (ADS)

Delwiche, K.; Hemond, H.; Senft-Grupp, S.

2015-12-01

We have built a novel bubble size sensor that is rugged, economical to build, and capable of accurately measuring methane bubble sizes in aquatic environments over long deployment periods. Accurate knowledge of methane bubble size is important to calculating atmospheric methane emissions from in-land waters. By routing bubbles past pairs of optical detectors, the sensor accurately measures bubbles sizes for bubbles between 0.01 mL and 1 mL, with slightly reduced accuracy for bubbles from 1 mL to 1.5 mL. The sensor can handle flow rates up to approximately 3 bubbles per second. Optional sensor attachments include a gas collection chamber for methane sampling and volume verification, and a detachable extension funnel to customize the quantity of intercepted bubbles. Additional features include a data-cable running from the deployed sensor to a custom surface buoy, allowing us to download data without disturbing on-going bubble measurements. We have successfully deployed numerous sensors in Upper Mystic Lake at depths down to 18 m, 1 m above the sediment. The resulting data gives us bubble size distributions and the precise timing of bubbling events over a period of several months. In addition to allowing us to characterize typical bubble size distributions, this data allows us to draw important conclusions about temporal variations in bubble sizes, as well as bubble dissolution rates within the water column.

Soap bubbles in analytical chemistry. Conductometric determination of sub-parts per million levels of sulfur dioxide with a soap bubble.

PubMed

Kanyanee, Tinakorn; Borst, Walter L; Jakmunee, Jaroon; Grudpan, Kate; Li, Jianzhong; Dasgupta, Purnendu K

2006-04-15

Soap bubbles provide a fascinating tool that is little used analytically. With a very low liquid volume to surface area ratio, a soap bubble can potentially provide a very useful interface for preconcentration where mass transfer to an interfacial surface is important. Here we use an automated system to create bubbles of uniform size and film thickness. We utilize purified Triton-X 100, a nonionic surfactant, to make soap bubbles. We use such bubbles as a gas-sampling interface. Incorporating hydrogen peroxide into the bubble provides a system where electrical conductance increases as the bubble is exposed to low concentrations of sulfur dioxide gas. We theoretically derive the conductance of a hollow conducting spherical thin film with spherical cap electrodes. We measure the film thickness by incorporating a dye in the bubble making solution and laser transmission photometry and find that it agrees well with the geometrically computed thickness. With the conductance of the bubble-making soap solution being measured by conventional methods, we show that the measured values of the bubble conductance with known bubble and electrode dimensions closely correspond to the theoretically computed value. Finally, we demonstrate that sub-ppm levels of SO(2) can readily be detected by the conductivity change of a hydrogen peroxide-doped soap bubble, measured in situ, when the gas flows around the bubble.

Use of a "small-bubble technique" to increase the success of Anwar's "big-bubble technique" for deep lamellar keratoplasty with complete baring of Descemet's membrane.

PubMed

Parthasarathy, Anand; Por, Yong Ming; Tan, Donald T H

2007-10-01

To describe a quick and simple "small-bubble" technique to immediately determine the success of attaining complete Descemet's membrane (DM) separation from corneal stroma through Anwar's "big-bubble" technique of deep anterior lamellar keratoplasty (DALK) for complete stromal removal. A partial trephination was followed by a lamellar dissection of the anterior stroma. Deep stromal air injection was then attempted to achieve the big bubble to help separate the stroma from the DM. To confirm that a big bubble had been achieved, a small air bubble was injected into the anterior chamber (AC) through a limbal paracentesis. If the small bubble is then seen at the corneal periphery, it confirms that the big-bubble separation of DM was successful because the convex nature of the bubble will cause it to protrude posteriorly, forcing the small AC bubble to the periphery. If the small AC bubble is not seen in the corneal periphery, this means that it is present in the centre, beneath the opaque corneal stroma, and therefore the big bubble has not been achieved. We used the small-bubble technique to confirm the presence of the big bubble in three (one keratoconus, one interstitial keratitis and one dense corneal scar) out of 41 patients who underwent DALK. The small-bubble technique confirmed that the big bubble was achieved in the eye of all three patients. Complete stromal removal with baring of the DM was achieved, and postoperatively all three eyes achieved best corrected vision of 6/6. The small-bubble technique can be a useful surgical tool for corneal surgeons attempting lamellar keratoplasty using the big-bubble technique. It helps in confirming the separation of DM from the deep stroma, which is important in achieving total stromal replacement. It will help to make the transition to lamellar keratoplasty smoother, enhance corneal graft success and improve visual outcomes in patients.

Acoustic bubble removal method

NASA Technical Reports Server (NTRS)

Trinh, E. H.; Elleman, D. D.; Wang, T. G. (Inventor)

1983-01-01

A method is described for removing bubbles from a liquid bath such as a bath of molten glass to be used for optical elements. Larger bubbles are first removed by applying acoustic energy resonant to a bath dimension to drive the larger bubbles toward a pressure well where the bubbles can coalesce and then be more easily removed. Thereafter, submillimeter bubbles are removed by applying acoustic energy of frequencies resonant to the small bubbles to oscillate them and thereby stir liquid immediately about the bubbles to facilitate their breakup and absorption into the liquid.

Rise characteristics of gas bubbles in a 2D rectangular column: VOF simulations vs experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Krishna, R.; Baten, J.M. van

About five centuries ago, Leonardo da Vinci described the sinuous motion of gas bubbles rising in water. The authors have attempted to simulate the rise trajectories of bubbles of 4, 5, 7, 8, 9, 12, and 20 mm in diameter rising in a 2D rectangular column filled with water. The simulations were carried out using the volume-of-fluid (VOF) technique developed by Hirt and Nichols (J. Computational Physics, 39, 201--225 (1981)). To solve the Navier-Stokes equations of motion the authors used a commercial solver, CFX 4.1c of AEA Technology, UK. They developed their own bubble-tracking algorithm to capture sinuous bubble motions.more » The 4 and 5 mm bubbles show large lateral motions observed by Da Vinci. The 7, 8 and 9 mm bubble behave like jellyfish. The 12 mm bubble flaps its wings like a bird. The extent of lateral motion of the bubbles decreases with increasing bubble size. Bubbles larger than 20 mm in size assume a spherical cap form and simulations of the rise characteristics match experiments exactly. VOF simulations are powerful tools for a priori determination of the morphology and rise characteristics of bubbles rising in a liquid. Bubble-bubble interactions are also properly modeled by the VOF technique.« less

Experimental study on wake structure of single rising clean bubble

NASA Astrophysics Data System (ADS)

Sato, Ayaka; Takedomi, Yuta; Shirota, Minori; Sanada, Toshiyuki; Watanabe, Masao

2007-11-01

Wake structure of clean bubble rising in quiescent silicone oil solution of photochromic dye is experimentally studied. A single bubble is generated, immediately after UV sheet light illuminates the part of the liquid just above the bubble generation nozzle in order to activate photochromic dye. Once the bubble passes across the colored part of the liquid, the bubble is accompanied by some portion of activated dye tracers; hence the flow structure in the rear of the single rising bubble is visualized. We capture stereo images of both wake structure and bubble motion. We study how wake structure changes with the increase in bubble size. We observe the stable axisymmetric wake structure, which is called `standing eddy' when bubble size is relatively small, and then wake structure becomes unstable and starts to oscillate with the increase in bubble size. With further increase in bubble size, a pair of streamwise vortices, which is called `double thread', is observed. We discuss in detail this transition from the steady wake to unsteady wake structure, especially double thread wake development and hairpin vortices shedding, in relation to the transition from rectilinear to spiral or zigzag bubble motions.

Bubble Departure from Metal-Graphite Composite Surfaces and Its Effects on Pool Boiling Heat Transfer

NASA Technical Reports Server (NTRS)

Chao, David F.; Sankovic, John M.; Motil, Brian J.; Yang, W-J.; Zhang, Nengli

2010-01-01

The formation and growth processes of a bubble in the vicinity of graphite micro-fiber tips on metal-graphite composite boiling surfaces and their effects on boiling behavior are investigated. It is discovered that a large number of micro bubbles are formed first at the micro scratches and cavities on the metal matrix in pool boiling. By virtue of the non-wetting property of graphite, once the growing micro bubbles touch the graphite tips, the micro bubbles are sucked by the tips and merged into larger micro bubbles sitting on the end of the tips. The micro bubbles grow rapidly and coalesce to form macro bubbles, each spanning several tips. The necking process of a detaching macro bubble is analyzed. It is revealed that a liquid jet is produced by sudden break-off of the bubble throat. The composite surfaces not only have higher temperatures in micro- and macrolayers but also make higher frequency of the bubble departure, which increase the average heat fluxes in both the bubble growth stage and in the bubble departure period. Based on these analyses, the enhancement mechanism of pool boiling heat transfer on composite surfaces is clearly revealed.

Review-Physicochemical hydrodynamics of gas bubbles in two phase electrochemical systems.

PubMed

Taqieddin, Amir; Nazari, Roya; Rajic, Ljiljana; Alshawabkeh, Akram

2017-01-01

Electrochemical systems suffer from poor management of evolving gas bubbles. Improved understanding of bubbles behavior helps to reduce overpotential, save energy and enhance the mass transfer during chemical reactions. This work investigates and reviews the gas bubbles hydrodynamics, behavior, and management in electrochemical cells. Although the rate of bubble growth over the electrode surface is well understood, there is no reliable prediction of bubbles break-off diameter from the electrode surface because of the complexity of bubbles motion near the electrode surface. Particle Image Velocimetry (PIV) and Laser Doppler Anemometry (LDA) are the most common experimental techniques to measure bubble dynamics. Although the PIV is faster than LDA, both techniques are considered expensive and time-consuming. This encourages adapting Computational Fluid Dynamics (CFD) methods as an alternative to study bubbles behavior. However, further development of CFD methods is required to include coalescence and break-up of bubbles for better understanding and accuracy. The disadvantages of CFD methods can be overcome by using hybrid methods. The behavior of bubbles in electrochemical systems is still a complex challenging topic which requires a better understanding of the gas bubbles hydrodynamics and their interactions with the electrode surface and bulk liquid, as well as between the bubbles itself.

Dynamics of Single Hydrogen Bubbles at a Platinum Microelectrode.

PubMed

Yang, Xuegeng; Karnbach, Franziska; Uhlemann, Margitta; Odenbach, Stefan; Eckert, Kerstin

2015-07-28

Bubble dynamics, including the formation, growth, and detachment, of single H2 bubbles was studied at a platinum microelectrode during the electrolysis of 1 M H2SO4 electrolyte. The bubbles were visualized through a microscope by a high-speed camera. Electrochemical measurements were conducted in parallel to measure the transient current. The periodic current oscillations, resulting from the periodic formation and detachment of single bubbles, allow the bubble lifetime and size to be predicted from the transient current. A comparison of the bubble volume calculated from the current and from the recorded bubble image shows a gas evolution efficiency increasing continuously with the growth of the bubble until it reaches 100%. Two different substrates, glass and epoxy, were used to embed the Pt wire. While nearly no difference was found with respect to the growth law for the bubble radius, the contact angle differs strongly for the two types of cell. Data provided for the contact point evolution further complete the image of single hydrogen bubble growth. Finally, the velocity field driven by the detached bubble was measured by means of PIV, and the effects of the convection on the subsequent bubble were evaluated.

Bubble Proliferation in Shock Wave Lithotripsy Occurs during Inertial Collapse

NASA Astrophysics Data System (ADS)

Pishchalnikov, Yuri A.; McAteer, James A.; Pishchalnikova, Irina V.; Williams, James C.; Bailey, Michael R.; Sapozhnikov, Oleg A.

2008-06-01

In shock wave lithotripsy (SWL), firing shock pulses at slow pulse repetition frequency (0.5 Hz) is more effective at breaking kidney stones than firing shock waves (SWs) at fast rate (2 Hz). Since at fast rate the number of cavitation bubbles increases, it appears that bubble proliferation reduces the efficiency of SWL. The goal of this work was to determine the basis for bubble proliferation when SWs are delivered at fast rate. Bubbles were studied using a high-speed camera (Imacon 200). Experiments were conducted in a test tank filled with nondegassed tap water at room temperature. Acoustic pulses were generated with an electromagnetic lithotripter (DoLi-50). In the focus of the lithotripter the pulses consisted of a ˜60 MPa positive-pressure spike followed by up to -8 MPa negative-pressure tail, all with a total duration of about 7 μs. Nonlinear propagation steepened the shock front of the pulses to become sufficiently thin (˜0.03 μm) to impose differential pressure across even microscopic bubbles. High-speed camera movies showed that the SWs forced preexisting microbubbles to collapse, jet, and break up into daughter bubbles, which then grew rapidly under the negative-pressure phase of the pulse, but later coalesced to re-form a single bubble. Subsequent bubble growth was followed by inertial collapse and, usually, rebound. Most, if not all, cavitation bubbles emitted micro-jets during their first inertial collapse and re-growth. After jetting, these rebounding bubbles could regain a spherical shape before undergoing a second inertial collapse. However, either upon this second inertial collapse, or sometimes upon the first inertial collapse, the rebounding bubble emerged from the collapse as a cloud of smaller bubbles rather than a single bubble. These daughter bubbles could continue to rebound and collapse for a few cycles, but did not coalesce. These observations show that the positive-pressure phase of SWs fragments preexisting bubbles but this initial fragmentation does not yield bubble proliferation, as the daughter bubbles coalesce to reform a single bubble. Instead, bubble proliferation is the product of the subsequent inertial collapses.

Behavior of Rapidly Sheared Bubble Suspensions

NASA Technical Reports Server (NTRS)

Sangani, A. S.; Kushch, V. I.; Hoffmann, M.; Nahra, H.; Koch, D. L.; Tsang, Y.

2002-01-01

An experiment to be carried out aboard the International Space Station is described. A suspension consisting of millimeter-sized bubbles in water containing some dissolved salt, which prevents bubbles from coalescing, will be sheared in a Couette cylindrical cell. Rotation of the outer cylinder will produce centrifugal force which will tend to accumulate the bubbles near the inner wall. The shearing will enhance collisions among bubbles creating thereby bubble phase pressure that will resist the tendency of the bubbles to accumulate near the inner wall. The bubble volume fraction and velocity profiles will be measured and compared with the theoretical predictions. Ground-based research on measurement of bubble phase properties and flow in vertical channel are described.

Cavitation inception by the backscattering of pressure waves from a bubble interface

DOE Office of Scientific and Technical Information (OSTI.GOV)

Takahira, Hiroyuki, E-mail: takahira@me.osakafu-u.ac.jp; Ogasawara, Toshiyuki, E-mail: oga@me.osakafu-u.ac.jp; Mori, Naoto, E-mail: su101064@edu.osakafu-u.ac.jp

2015-10-28

The secondary cavitation that occurs by the backscattering of focused ultrasound from a primary cavitation bubble caused by the negative pressure part of the ultrasound (Maxwell, et al., 2011) might be useful for the energy exchange due to bubble oscillations in High Intensity Focused Ultrasound (HIFU). The present study is concerned with the cavitation inception by the backscattering of ultrasound from a bubble. In the present experiment, a laser-induced bubble which is generated by a pulsed focused laser beam with high intensity is utilized as a primary cavitation bubble. After generating the bubble, focused ultrasound is emitted to the bubble.more » The acoustic field and the bubble motion are observed with a high-speed video camera. It is confirmed that the secondary cavitation bubble clouds are generated by the backscattering from the laser-induced bubble. The growth of cavitation bubble clouds is analyzed with the image processing method. The experimental results show that the height and width of the bubble clouds grow in stepwise during their evolution. The direct numerical simulations are also conducted for the backscattering of incident pressure waves from a bubble in order to evaluate a pressure field near the bubble. It is shown that the ratio of a bubble collapse time t{sub 0} to a characteristic time of wave propagation t{sub S}, η = t{sub 0}/t{sub s}, is an important determinant for generating negative pressure region by backscattering. The minimum pressure location by the backscattering in simulations is in good agreement with the experiment.« less

Spontaneous and Directional Bubble Transport on Porous Copper Wires with Complex Shapes in Aqueous Media.

PubMed

Li, Wenjing; Zhang, Jingjing; Xue, Zhongxin; Wang, Jingming; Jiang, Lei

2018-01-24

Manipulation of gas bubble behaviors is crucial for gas bubble-related applications. Generally, the manipulation of gas bubble behaviors generally takes advantage of their buoyancy force. It is very difficult to control the transportation of gas bubbles in a specific direction. Several approaches have been developed to collect and transport bubbles in aqueous media; however, most reliable and effective manipulation of gas bubbles in aqueous media occurs on the interfaces with simple shapes (i.e., cylinder and cone shapes). Reliable strategies for spontaneous and directional transport of gas bubbles on interfaces with complex shapes remain enormously challenging. Herein, a type of 3D gradient porous network was constructed on copper wire interfaces, with rectangle, wave, and helix shapes. The superhydrophobic copper wires were immersed in water, and continuous and stable gas films then formed on the interfaces. With the assistance of the Laplace pressure gradient between two bubbles, gas bubbles (including microscopic gas bubbles) in the aqueous media were subsequently transported, continuously and directionally, on the copper wires with complex shapes. The small gas bubbles always moved to the larger ones.

Predawn plasma bubble cluster observed in Southeast Asia

NASA Astrophysics Data System (ADS)

Watthanasangmechai, Kornyanat; Yamamoto, Mamoru; Saito, Akinori; Tsunoda, Roland; Yokoyama, Tatsuhiro; Supnithi, Pornchai; Ishii, Mamoru; Yatini, Clara

2016-06-01

Predawn plasma bubble was detected as deep plasma depletion by GNU Radio Beacon Receiver (GRBR) network and in situ measurement onboard Defense Meteorological Satellite Program F15 (DMSPF15) satellite and was confirmed by sparse GPS network in Southeast Asia. In addition to the deep depletion, the GPS network revealed the coexisting submesoscale irregularities. A deep depletion is regarded as a primary bubble. Submesoscale irregularities are regarded as secondary bubbles. Primary bubble and secondary bubbles appeared together as a cluster with zonal wavelength of 50 km. An altitude of secondary bubbles happened to be lower than that of the primary bubble in the same cluster. The observed pattern of plasma bubble cluster is consistent with the simulation result of the recent high-resolution bubble (HIRB) model. This event is only a single event out of 76 satellite passes at nighttime during 3-25 March 2012 that significantly shows plasma depletion at plasma bubble wall. The inside structure of the primary bubble was clearly revealed from the in situ density data of DMSPF15 satellite and the ground-based GRBR total electron content.

Three anamorphic yeast species Candida sanitii sp. nov., Candida sekii sp. nov. and Candida suwanaritii, three novel yeasts in the Saturnispora clade isolated in Thailand.

PubMed

Limtong, Savitree; Kaewwichian, Rungluk; Am-In, Somjit; Boonmak, Chanita; Jindamorakot, Sasitorn; Yongmanitchai, Wichien; Srisuk, Natana; Kawasaki, Hiroko; Nakase, Takashi

2010-02-01

Nine strains of three novel anamorphic yeast species were obtained from samples collected in Thailand including six strains (RV96, RV152, R14, RS9, RS58 and EA1) obtained from estuarine waters collected from two mangrove forests, one strain (ST84) from insect frass and two strains (SR16 and UB13) from forest soils. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, and the sequence analysis of the D1/D2 domain of the large subunit rRNA gene, the nine strains were found to represent three novel Candida species in the Saturnispora clade. Five strains (RV96, RV152, R14, RS9 and RS58) were assigned as a single novel species, which was named Candida sanitii sp. nov. The type strain is RV152(T) (BCC 25967(T)=NBRC 103864(T)=CBS 10864(T)). Strain EA1 was named as Candida suwanaritii sp. nov. The type strain is EA1(T) (BCC 29900(T)=NBRC 104877(T)=CBS 11021(T)). Three strains (ST84, SR16 and UB13) represented another novel species, for which Candida sekii sp. nov. is proposed. The type strain is ST84(T) (BCC 8320(T)=NBRC 105671(T)=CBS 10931(T)).

Is obesity contagious by way of body image? A study on Japanese female students in the United States.

PubMed

Bagrowicz, Rinako; Watanabe, Chiho; Umezaki, Masahiro

2013-10-01

Although it has been suggested that obesity is 'contagious' within the social network, direct cause of this spread of obesity remains unclear. This study hypothesized that Body Image (BI), the perception of one's own body size, may play a role in this obesity spread, since a high prevalence of obesity could shift people's perception of 'what is normal'. Young Japanese females (n = 53) were interviewed within 1 month after moving to New York City, where the prevalence of obesity is substantially higher than that of their home country, Japan. Each participant was examined for her BI in terms of current body size (CBS) and ideal body size (IBS). They were interviewed again 2 months after the first examination. Between the two interviews, the participants' CBS was decreased (having thinner self-image), while the IBS increased (having fatter ideal-image), leading to less dissatisfaction (smaller CBS-IBS) with their body size. These results suggest that one's BI could change in a period as short as 2 months, possibly because of being surrounded by more obese people. The IBS change was positively associated with BMI change (increased by 0.4 ± 0.6 kg/m²), warranting further study on the role of BI in the spread of obesity.

Degradation and mineralization of 2-chloro-, 3-chloro- and 4-chlorobiphenyl by a newly characterized natural bacterial strain isolated from an electrical transformer fluid-contaminated soil.

PubMed

Ilori, Matthew O; Robinson, Gary K; Adebusoye, Sunday A

2008-01-01

A bacterium classified as Achromobacter xylosoxidans strain IR08 by phenotypic typing coupled with 16S rRNA gene analysis was isolated from a soil contaminated with electrical transformer fluid for over sixty years using Aroclor 1221 as an enrichment substrate. The substrate utilization profiles revealed that IR08 could grow on all three monochlorobiphenyls (CBs), 2,4'- and 4,4'-dichlorobiphenyl as well as 2-chlorobenzoate (2-CBA), 3-CBA, 4-CBA, and 2,3-dichlorobenzoate. Unusually, growth was poorly sustained on biphenyl and benzoate. In growth experiments, IR08 degraded all CBs (0.27 mmol/L) in less than 96 h with concomitant stoichiometric release of inorganic chloride and growth yields were 2-3 times higher than those observed on biphenyl. In contrast to most of the chlorobiphenyl-degrading strains described in the literature, which are reported to form CBA, no metabolite was identified in the culture broth by HPLC analysis. When co-incubated with respective CBs and biphenyl, strain IR08 preferentially utilized the chlorinated analogues in less than 96 h while it took another 264 h before 90% of the initially supplied biphenyl could be degraded. The promotion of co-metabolic transformation of halogenated substrates by the inclusion of their non-halogenated derivatives may not therefore, result in universal benefits.

Telephone-Based Cognitive-Behavioral Screening for Frontotemporal Changes in Patients with Amyotrophic Lateral Sclerosis (ALS)

PubMed Central

Christodoulou, Georgia; Gennings, Chris; Hupf, Jonathan; Factor-Litvak, Pam; Murphy, Jennifer; Goetz, Raymond R.; Mitsumoto, Hiroshi

2017-01-01

Objective To establish a valid and reliable battery of measures to evaluate frontotemporal dementia (FTD) in patients with ALS over the phone. Methods Thirty-one subjects were administered either in-person or telephone-based screening followed by the opposite mode of testing two weeks later, using a modified version of the UCSF Cognitive Screening Battery. Results Equivalence testing was performed for in-person and telephone-based tests. The standard ALS Cognitive Behavioral Screen (ALS-CBS) showed statistical equivalence at the 5% significance level when compared to a revised phone-version of the ALS-CBS. In addition, the Controlled Oral Word Association Test (COWAT) and Center for Neurologic Study-Lability Scale (CNS-LS) were also found to be equivalent at the 5% and 10% significance level respectively. Similarly, the Mini-Mental State Examination (MMSE) and the well-established Telephone Interview for Cognitive Status (TICS) were also statistically equivalent. Equivalence could not be claimed for the ALS-Frontal Behavioral Inventory (ALS-FBI) caregiver interview and the Written Verbal Fluency Index (WVFI). Conclusions Our study suggests that telephone-based versions of the ALS-CBS, COWAT, and CNS-LS may offer clinicians valid tools to detect frontotemporal changes in the ALS population. Development of telephone-based cognitive testing for ALS could become an integral resource for population-based research in the future. PMID:27121545

Telephone based cognitive-behavioral screening for frontotemporal changes in patients with amyotrophic lateral sclerosis (ALS).

PubMed

Christodoulou, Georgia; Gennings, Chris; Hupf, Jonathan; Factor-Litvak, Pam; Murphy, Jennifer; Goetz, Raymond R; Mitsumoto, Hiroshi

Our objective was to establish a valid and reliable battery of measures to evaluate frontotemporal dementia (FTD) in patients with ALS over the telephone. Thirty-one subjects were administered either in-person or by telephone-based screening followed by the opposite mode of testing two weeks later, using a modified version of the UCSF Cognitive Screening Battery. Equivalence testing was performed for in-person and telephone based tests. The standard ALS Cognitive Behavioral Screen (ALS-CBS) showed statistical equivalence at the 5% significance level compared to a revised phone version of the ALS-CBS. In addition, the Controlled Oral Word Association Test (COWAT) and Center for Neurologic Study-Lability Scale (CNS-LS) were also found to be equivalent at the 5% and 10% significance level, respectively. Similarly, the Mini-Mental State Examination (MMSE) and the well-established Telephone Interview for Cognitive Status (TICS) were also statistically equivalent. Equivalence could not be claimed for the ALS-Frontal Behavioral Inventory (ALS-FBI) caregiver interview and the Written Verbal Fluency Index (WVFI). In conclusion, our study suggests that telephone-based versions of the ALS-CBS, COWAT, and CNS-LS may offer clinicians valid tools to detect frontotemporal changes in the ALS population. Development of telephone based cognitive testing for ALS could become an integral resource for population based research in the future.

Probing phenylalanine/adenine pi-stacking interactions in protein complexes with explicitly correlated and CCSD(T) computations.

PubMed

Copeland, Kari L; Anderson, Julie A; Farley, Adam R; Cox, James R; Tschumper, Gregory S

2008-11-13

To examine the effects of pi-stacking interactions between aromatic amino acid side chains and adenine bearing ligands in crystalline protein structures, 26 toluene/(N9-methyl)adenine model configurations have been constructed from protein/ligand crystal structures. Full geometry optimizations with the MP2 method cause the 26 crystal structures to collapse to six unique structures. The complete basis set (CBS) limit of the CCSD(T) interaction energies has been determined for all 32 structures by combining explicitly correlated MP2-R12 computations with a correction for higher-order correlation effects from CCSD(T) calculations. The CCSD(T) CBS limit interaction energies of the 26 crystal structures range from -3.19 to -6.77 kcal mol (-1) and average -5.01 kcal mol (-1). The CCSD(T) CBS limit interaction energies of the optimized complexes increase by roughly 1.5 kcal mol (-1) on average to -6.54 kcal mol (-1) (ranging from -5.93 to -7.05 kcal mol (-1)). Corrections for higher-order correlation effects are extremely important for both sets of structures and are responsible for the modest increase in the interaction energy after optimization. The MP2 method overbinds the crystal structures by 2.31 kcal mol (-1) on average compared to 4.50 kcal mol (-1) for the optimized structures.

Accurate determination of the binding energy of the formic acid dimer: The importance of geometry relaxation

NASA Astrophysics Data System (ADS)

Kalescky, Robert; Kraka, Elfi; Cremer, Dieter

2014-02-01

The formic acid dimer in its C2h-symmetrical cyclic form is stabilized by two equivalent H-bonds. The currently accepted interaction energy is 18.75 kcal/mol whereas the experimental binding energy D0 value is only 14.22 ±0.12 kcal/mol [F. Kollipost, R. W. Larsen, A. V. Domanskaya, M. Nörenberg, and M. A. Suhm, J. Chem. Phys. 136, 151101 (2012)]. Calculation of the binding energies De and D0 at the CCSD(T) (Coupled Cluster with Single and Double excitations and perturbative Triple excitations)/CBS (Complete Basis Set) level of theory, utilizing CCSD(T)/CBS geometries and the frequencies of the dimer and monomer, reveals that there is a 3.2 kcal/mol difference between interaction energy and binding energy De, which results from (i) not relaxing the geometry of the monomers upon dissociation of the dimer and (ii) approximating CCSD(T) correlation effects with MP2. The most accurate CCSD(T)/CBS values obtained in this work are De = 15.55 and D0 = 14.32 kcal/mol where the latter binding energy differs from the experimental value by 0.1 kcal/mol. The necessity of employing augmented VQZ and VPZ calculations and relaxing monomer geometries of H-bonded complexes upon dissociation to obtain reliable binding energies is emphasized.

Quantum chemical investigation of the primary thermal pyrolysis reactions of the sodium carboxylate group in a brown coal model.

PubMed

Li, Jian; Zhang, Baisheng; Zhang, Zhiqiang; Yan, Kefeng; Kang, Lixun

2014-12-01

The primary pyrolysis mechanisms of the sodium carboxylate group in sodium benzoate-used as a model compound of brown coal-were studied by performing quantum chemical computations using B3LYP and the CBS method. Various possible reaction pathways involving reactions such as unimolecular and bimolecular decarboxylation and decarbonylation, crosslinking, and radical attack in the brown coal matrix were explored. Without the participation of reactive radicals, unimolecular decarboxylation to release CO2 was calculated to be the most energetically favorable primary reaction pathway at the B3LYP/6-311+G (d, p) level of theory, and was also found to be more energetically favorable than decarboxylation of an carboxylic acid group. When CBS-QBS results were included, crosslinking between the sodium carboxylate group and the carboxylic acid and the decarboxylation of the sodium carboxylate group (catalyzed by the phenolic hydroxyl group) were found to be possible; this pathway competes with unimolecular decarboxylation of the sodium carboxylate group. Provided that H and CH3 radicals are present in the brown coal matrix and can access the sodium carboxylate group, accelerated pyrolysis of the sodium carboxylate group becomes feasible, leading to the release of an Na atom or an NaCO2 radical at the B3LYP/6-311+G (d, p) or CBS-QB3 level of theory, respectively.

Anionic water pentamer and hexamer clusters: An extensive study of structures and energetics

NASA Astrophysics Data System (ADS)

Ünal, Aslı; Bozkaya, Uǧur

2018-03-01

An extensive study of structures and energetics for anionic pentamer and hexamer clusters is performed employing high level ab initio quantum chemical methods, such as the density-fitted orbital-optimized linearized coupled-cluster doubles (DF-OLCCD), coupled-cluster singles and doubles (CCSD), and coupled-cluster singles and doubles with perturbative triples [CCSD(T)] methods. In this study, sixteen anionic pentamer clusters and eighteen anionic hexamer clusters are reported. Relative, binding, and vertical detachment energies (VDE) are presented at the complete basis set limit (CBS), extrapolating energies of aug4-cc-pVTZ and aug4-cc-pVQZ custom basis sets. The largest VDE values obtained at the CCSD(T)/CBS level are 9.9 and 11.2 kcal mol-1 for pentamers and hexamers, respectively, which are in very good agreement with the experimental values of 9.5 and 11.1 kcal mol-1. Our binding energy results, at the CCSD(T)/CBS level, indicate strong bindings in anionic clusters due to hydrogen bond interactions. The average binding energy per water molecules is -5.0 and -5.3 kcal mol-1 for pentamers and hexamers, respectively. Furthermore, our results demonstrate that the DF-OLCCD method approaches to the CCSD(T) quality for anionic clusters. The inexpensive analytic gradients of DF-OLCCD compared to CCSD or CCSD(T) make it very attractive for high-accuracy studies.

Anionic water pentamer and hexamer clusters: An extensive study of structures and energetics.

PubMed

Ünal, Aslı; Bozkaya, Uğur

2018-03-28

An extensive study of structures and energetics for anionic pentamer and hexamer clusters is performed employing high level ab initio quantum chemical methods, such as the density-fitted orbital-optimized linearized coupled-cluster doubles (DF-OLCCD), coupled-cluster singles and doubles (CCSD), and coupled-cluster singles and doubles with perturbative triples [CCSD(T)] methods. In this study, sixteen anionic pentamer clusters and eighteen anionic hexamer clusters are reported. Relative, binding, and vertical detachment energies (VDE) are presented at the complete basis set limit (CBS), extrapolating energies of aug4-cc-pVTZ and aug4-cc-pVQZ custom basis sets. The largest VDE values obtained at the CCSD(T)/CBS level are 9.9 and 11.2 kcal mol -1 for pentamers and hexamers, respectively, which are in very good agreement with the experimental values of 9.5 and 11.1 kcal mol -1 . Our binding energy results, at the CCSD(T)/CBS level, indicate strong bindings in anionic clusters due to hydrogen bond interactions. The average binding energy per water molecules is -5.0 and -5.3 kcal mol -1 for pentamers and hexamers, respectively. Furthermore, our results demonstrate that the DF-OLCCD method approaches to the CCSD(T) quality for anionic clusters. The inexpensive analytic gradients of DF-OLCCD compared to CCSD or CCSD(T) make it very attractive for high-accuracy studies.

Toward High-Level Theoretical Studies of Large Biodiesel Molecules: An ONIOM [QCISD(T)/CBS:DFT] Study of the Reactions between Unsaturated Methyl Esters (C nH2 n-1COOCH3) and Hydrogen Radical.

PubMed

Zhang, Lidong; Meng, Qinghui; Chi, Yicheng; Zhang, Peng

2018-05-31

A two-layer ONIOM[QCISD(T)/CBS:DFT] method was proposed for the high-level single-point energy calculations of large biodiesel molecules and was validated for the hydrogen abstraction reactions of unsaturated methyl esters that are important components of real biodiesel. The reactions under investigation include all the reactions on the potential energy surface of C n H 2 n-1 COOCH 3 ( n = 2-5, 17) + H, including the hydrogen abstraction, the hydrogen addition, the isomerization (intramolecular hydrogen shift), and the β-scission reactions. By virtue of the introduced concept of chemically active center, a unified specification of chemically active portion for the ONIOM (ONIOM = our own n-layered integrated molecular orbital and molecular mechanics) method was proposed to account for the additional influence of C═C double bond. The predicted energy barriers and heats of reaction by using the ONIOM method are in very good agreement with those obtained by using the widely accepted high-level QCISD(T)/CBS theory, as verified by the computational deviations being less than 0.15 kcal/mol, for almost all the reaction pathways under investigation. The method provides a computationally accurate and affordable approach to combustion chemists for high-level theoretical chemical kinetics of large biodiesel molecules.

The Untold Story of Pyrocumulonimbus

NASA Astrophysics Data System (ADS)

Fromm, Michael; Lindsey, Daniel; Servranckx, René; Yue, Glenn; Trickl, Thomas; Sica, Robert; Doucet, Paul; Godin-Beekman, Sophie

2010-05-01

Wildfire is becoming the focus of increasing attention with heightened concerns related to climate change, global warming, and safety in the urban-wildland interface. One aspect of wildfire behavior has been totally overlooked until recently—the role of pyrocumulonimbus (pyroCb for short) in both firestorm dynamics and atmospheric impact. PyroCb are fire-started or -augmented thunderstorms that in their most extreme manifestation inject huge abundances of smoke and other biomass burning emissions into the lower stratosphere. The observed hemispheric spread of smoke and other biomass burning emissions could have important climate consequences. Such an extreme injection by thunderstorms was previously judged to be impossible because the extratopical tropopause is considered to be an effective lid on convection. At least two recurring themes have developed as pyroCb research unfolds. First, some "mystery layer" events—puzzling stratospheric aerosol layer observations— and layers reported as volcanic aerosol can now be explained in terms of pyroconvection as the "smoking gun." Secondly, pyroCb events occur with surprising frequency, and they are likely a relevant aspect of several historic wildfires. Here we will show that pyroCbs offer an alternative explanation for previously assumed volcanic aerosols in 1989-1991. In addition, we survey the Canada/USA fire season of 2002 and identify 17 pyroCbs, some of which are associated with newsworthy fires such as Hayman, Rodeo/Chediski, and Biscuit fires. Several of these pyroCbs injected smoke into the lowermost stratosphere.

The influence of external factors on the corrosion resistance of high temperature superconductor thin films against moisture

NASA Astrophysics Data System (ADS)

Murugesan, M.; Obara, H.; Yamasaki, H.; Kosaka, S.

2006-12-01

High temperature superconductor (HTS) thin films have been systematically investigated for their corrosion resistance against moisture by studying the role of external factors such as temperature (T), relative humidity (RH), and the type of substrates in the corrosion. In general, (i) the corrosion is progressed monotonously with increasing T as well as RH, (ii) a threshold level of water vapor is needed to cause degradation, and (iii) between T and RH, the influence of T is more dominant. HTS films on SrTiO3 and CeO2 buffered sapphire (cbs) substrates showed better corrosion stability and a low rate of degradation in the critical current density as compared to that of the film grown on MgO substrate. Between DyBa2Cu3Oz (DBCO) and YBa2Cu3Oz, the former is reproducibly found to have many fold higher corrosion resistance against moisture. This observed enhancement in the corrosion resistance in DBCO could be explained by the improved microstructure in the films and the better lattice matching with the substrate. Thus, the dual advantage of DBCO/cbs films, i.e., the enhanced corrosion stability of DBCO and the appropriate dielectric properties of sapphire, can be readily exploited for the use of DBCO/cbs films in the microwave and power devices.

Composite vibrational spectroscopy of the group 12 difluorides: ZnF2, CdF2, and HgF2.

PubMed

Solomonik, Victor G; Smirnov, Alexander N; Navarkin, Ilya S

2016-04-14

The vibrational spectra of group 12 difluorides, MF2 (M = Zn, Cd, Hg), were investigated via coupled cluster singles, doubles, and perturbative triples, CCSD(T), including core correlation, with a series of correlation consistent basis sets ranging in size from triple-zeta through quintuple-zeta quality, which were then extrapolated to the complete basis set (CBS) limit using a variety of extrapolation procedures. The explicitly correlated coupled cluster method, CCSD(T)-F12b, was employed as well. Although exhibiting quite different convergence behavior, the F12b method yielded the CBS limit estimates closely matching more computationally expensive conventional CBS extrapolations. The convergence with respect to basis set size was examined for the contributions entering into composite vibrational spectroscopy, including those from higher-order correlation accounted for through the CCSDT(Q) level of theory, second-order spin-orbit coupling effects assessed within four-component and two-component relativistic formalisms, and vibrational anharmonicity evaluated via a perturbative treatment. Overall, the composite results are in excellent agreement with available experimental values, except for the CdF2 bond-stretching frequencies compared to spectral assignments proposed in a matrix isolation infrared and Raman study of cadmium difluoride vapor species [Loewenschuss et al., J. Chem. Phys. 50, 2502 (1969); Givan and Loewenschuss, J. Chem. Phys. 72, 3809 (1980)]. These assignments are called into question in the light of the composite results.

Composite vibrational spectroscopy of the group 12 difluorides: ZnF2, CdF2, and HgF2

NASA Astrophysics Data System (ADS)

Solomonik, Victor G.; Smirnov, Alexander N.; Navarkin, Ilya S.

2016-04-01

The vibrational spectra of group 12 difluorides, MF2 (M = Zn, Cd, Hg), were investigated via coupled cluster singles, doubles, and perturbative triples, CCSD(T), including core correlation, with a series of correlation consistent basis sets ranging in size from triple-zeta through quintuple-zeta quality, which were then extrapolated to the complete basis set (CBS) limit using a variety of extrapolation procedures. The explicitly correlated coupled cluster method, CCSD(T)-F12b, was employed as well. Although exhibiting quite different convergence behavior, the F12b method yielded the CBS limit estimates closely matching more computationally expensive conventional CBS extrapolations. The convergence with respect to basis set size was examined for the contributions entering into composite vibrational spectroscopy, including those from higher-order correlation accounted for through the CCSDT(Q) level of theory, second-order spin-orbit coupling effects assessed within four-component and two-component relativistic formalisms, and vibrational anharmonicity evaluated via a perturbative treatment. Overall, the composite results are in excellent agreement with available experimental values, except for the CdF2 bond-stretching frequencies compared to spectral assignments proposed in a matrix isolation infrared and Raman study of cadmium difluoride vapor species [Loewenschuss et al., J. Chem. Phys. 50, 2502 (1969); Givan and Loewenschuss, J. Chem. Phys. 72, 3809 (1980)]. These assignments are called into question in the light of the composite results.

Centipod WEC, Advanced Controls, Resultant LCOE

DOE Data Explorer

McCall, Alan

2016-02-15

Project resultant LCOE model after implementation of MPC controller. Contains AEP, CBS, model documentation, and LCOE content model. This is meant for comparison with this project's baseline LCOE model.

Bubble migration in a compacting crystal-liquid mush

NASA Astrophysics Data System (ADS)

Boudreau, Alan

2016-04-01

Recent theoretical models have suggested that bubbles are unlikely to undergo significant migration in a compaction crystal mush by capillary invasion while the system remains partly molten. To test this, experiments of bubble migration during compaction in a crystal-liquid mush were modeled using deformable foam crystals in corn syrup in a volumetric burette, compacted with rods of varying weights. A bubble source was provided by sodium bicarbonate (Alka-Seltzer®). Large bubbles (>several crystal sizes) are pinched by the compacting matrix and become overpressured and deformed as the bubbles experience a load change from hydrostatic to lithostatic. Once they begin to move, they move much faster than the compaction-driven liquid. Bubbles that are about the same size as the crystals but larger than the narrower pore throats move by deformation or breaking into smaller bubbles as they are forced through pore restrictions. Bubbles that are less than the typical pore diameter generally move with the liquid: The liquid + bubble mixture behaves as a single phase with a lower density than the bubble-free liquid, and as a consequence it rises faster than bubble-free liquid and allows for faster compaction. The overpressure required to force a bubble through the matrix (max grain size = 5 mm) is modest, about 5 %, and it is estimated that for a grain size of 1 mm, the required overpressure would be about 25 %. Using apatite distribution in a Stillwater olivine gabbro as an analog for bubble nucleation and growth, it is suggested that relatively large bubbles initially nucleate and grow in liquid-rich channels that develop late in the compaction history. Overpressure from compaction allows bubbles to rise higher into hotter parts of the crystal pile, where they redissolve and increase the volatile content of the liquid over what it would have without the bubble migration, leading to progressively earlier vapor saturation during crystallization of the interstitial liquid. Bubbles can also move rapidly by `surfing' on porosity waves that can develop in a compacting mush.

Study on the bubble transport mechanism in an acoustic standing wave field.

PubMed

Xi, Xiaoyu; Cegla, Frederic B; Lowe, Michael; Thiemann, Andrea; Nowak, Till; Mettin, Robert; Holsteyns, Frank; Lippert, Alexander

2011-12-01

The use of bubbles in applications such as surface chemistry, drug delivery, and ultrasonic cleaning etc. has been enormously popular in the past two decades. It has been recognized that acoustically-driven bubbles can be used to disturb the flow field near a boundary in order to accelerate physical or chemical reactions on the surface. The interactions between bubbles and a surface have been studied experimentally and analytically. However, most of the investigations focused on violently oscillating bubbles (also known as cavitation bubble), less attention has been given to understand the interactions between moderately oscillating bubbles and a boundary. Moreover, cavitation bubbles were normally generated in situ by a high intensity laser beam, little experimental work has been carried out to study the translational trajectory of a moderately oscillating bubble in an acoustic field and subsequent interactions with the surface. This paper describes the design of an ultrasonic test cell and explores the mechanism of bubble manipulation within the test cell. The test cell consists of a transducer, a liquid medium and a glass backing plate. The acoustic field within the multi-layered stack was designed in such a way that it was effectively one dimensional. This was then successfully simulated by a one dimensional network model. The model can accurately predict the impedance of the test cell as well as the mode shape (distribution of particle velocity and stress/pressure field) within the whole assembly. The mode shape of the stack was designed so that bubbles can be pushed from their injection point onto a backing glass plate. Bubble radial oscillation was simulated by a modified Keller-Miksis equation and bubble translational motion was derived from an equation obtained by applying Newton's second law to a bubble in a liquid medium. Results indicated that the bubble trajectory depends on the acoustic pressure amplitude and initial bubble size: an increase of pressure amplitude or a decrease of bubble size forces bubbles larger than their resonant size to arrive at the target plate at lower heights, while the trajectories of smaller bubbles are less influenced by these factors. The test cell is also suitable for testing the effects of drag force on the bubble motion and for studying the bubble behavior near a surface. Copyright © 2011 Elsevier B.V. All rights reserved.

Wetting of soap bubbles on hydrophilic, hydrophobic, and superhydrophobic surfaces

NASA Astrophysics Data System (ADS)

Arscott, Steve

2013-06-01

Wetting of sessile bubbles on various wetting surfaces (solid and liquid) has been studied. A model is presented for the apparent contact angle of a sessile bubble based on a modified Young's equation--the experimental results agree with the model. Wetting a hydrophilic surface results in a bubble contact angle of 90° whereas using a superhydrophobic surface one observes 134°. For hydrophilic surfaces, the bubble angle diminishes with bubble radius whereas on a superhydrophobic surface, the bubble angle increases. The size of the plateau borders governs the bubble contact angle, depending on the wetting of the surface.

Bubble Combustion

NASA Technical Reports Server (NTRS)

Corrigan, Jackie

2004-01-01

A method of energy production that is capable of low pollutant emissions is fundamental to one of the four pillars of NASA s Aeronautics Blueprint: Revolutionary Vehicles. Bubble combustion, a new engine technology currently being developed at Glenn Research Center promises to provide low emissions combustion in support of NASA s vision under the Emissions Element because it generates power, while minimizing the production of carbon dioxide (CO2) and nitrous oxides (NOx), both known to be Greenhouse gases. and allows the use of alternative fuels such as corn oil, low-grade fuels, and even used motor oil. Bubble combustion is analogous to the inverse of spray combustion: the difference between bubble and spray combustion is that spray combustion is spraying a liquid in to a gas to form droplets, whereas bubble combustion involves injecting a gas into a liquid to form gaseous bubbles. In bubble combustion, the process for the ignition of the bubbles takes place on a time scale of less than a nanosecond and begins with acoustic waves perturbing each bubble. This perturbation causes the local pressure to drop below the vapor pressure of the liquid thus producing cavitation in which the bubble diameter grows, and upon reversal of the oscillating pressure field, the bubble then collapses rapidly with the aid of the high surface tension forces acting on the wall of the bubble. The rapid and violent collapse causes the temperatures inside the bubbles to soar as a result of adiabatic heating. As the temperatures rise, the gaseous contents of the bubble ignite with the bubble itself serving as its own combustion chamber. After ignition, this is the time in the bubble s life cycle where power is generated, and CO2, and NOx among other species, are produced. However, the pollutants CO2 and NOx are absorbed into the surrounding liquid. The importance of bubble combustion is that it generates power using a simple and compact device. We conducted a parametric study using CAVCHEM, a computational model developed at Glenn, that simulates the cavitational collapse of a single bubble in a liquid (water) and the subsequent combustion of the gaseous contents inside the bubble. The model solves the time-dependent, compressible Navier-Stokes equations in one-dimension with finite-rate chemical kinetics using the CHEMKIN package. Specifically, parameters such as frequency, pressure, bubble radius, and the equivalence ratio were varied while examining their effect on the maximum temperature, radius, and chemical species. These studies indicate that the radius of the bubble is perhaps the most critical parameter governing bubble combustion dynamics and its efficiency. Based on the results of the parametric studies, we plan on conducting experiments to study the effect of ultrasonic perturbations on the bubble generation process with respect to the bubble radius and size distribution.

How are soap bubbles blown? Fluid dynamics of soap bubble blowing

NASA Astrophysics Data System (ADS)

Davidson, John; Lambert, Lori; Sherman, Erica; Wei, Timothy; Ryu, Sangjin

2013-11-01

Soap bubbles are a common interfacial fluid dynamics phenomenon having a long history of delighting not only children and artists but also scientists. In contrast to the dynamics of liquid droplets in gas and gas bubbles in liquid, the dynamics of soap bubbles has not been well documented. This is possibly because studying soap bubbles is more challenging due to there existing two gas-liquid interfaces. Having the thin-film interface seems to alter the characteristics of the bubble/drop creation process since the interface has limiting factors such as thickness. Thus, the main objective of this study is to determine how the thin-film interface differentiates soap bubbles from gas bubbles and liquid drops. To investigate the creation process of soap bubbles, we constructed an experimental model consisting of air jet flow and a soap film, which consistently replicates the conditions that a human produces when blowing soap bubbles, and examined the interaction between the jet and the soap film using the high-speed videography and the particle image velocimetry.

Acoustic measurement of bubble size and position in a piezo driven inkjet printhead

NASA Astrophysics Data System (ADS)

van der Bos, Arjan; Jeurissen, Roger; de Jong, Jos; Stevens, Richard; Versluis, Michel; Reinten, Hans; van den Berg, Marc; Wijshoff, Herman; Lohse, Detlef

2008-11-01

A bubble can be entrained in the ink channel of a piezo-driven inkjet printhead, where it grows by rectified diffusion. If large enough, the bubble counteracts the pressure buildup at the nozzle, resulting in nozzle failure. Here an acoustic sizing method for the volume and position of the bubble is presented. The bubble response is detected by the piezo actuator itself, operating in a sensor mode. The method used to determine the volume and position of the bubble is based on a linear model in which the interaction between the bubble and the channel are included. This model predicts the acoustic signal for a given position and volume of the bubble. The inverse problem is to infer the position and volume of the bubble from the measured acoustic signal. By solving it, we can thus acoustically measure size and position of the bubble. The validity of the presented method is supported by time-resolved optical observations of the dynamics of the bubble within an optically accessible ink-jet channel.

Investigation of the interaction dynamics of a pair of laser-induced bubbles generated at the same time through double-exposure strobe method and numerical simulations

NASA Astrophysics Data System (ADS)

Han, Bing; Liu, Liu; Ni, Xiao-Wu

2017-08-01

In order to understand the interaction dynamics of a pair of laser-induced bubbles, a double-exposure strobe photography experimental setup is build up to study the temporal evolution of the bubble pairs and to measure the transient bubble-interface moving speed. The interaction mechanisms of the bubble pairs are discussed together with the numerical results obtained through OpenFOAM. It is shown that the direction and the velocity of the jetting could be controlled by the relative size and the relative initiation distance of the bubble pair, when the bubbles are generated at the same time, i.e., in-phase. The liquid jet is considered to be a penetrating jet. The jet is originated from the smaller bubble and clearly protruding outside of the bigger bubble. The parameter space of the relative size and the initiation distance of the bubble pair allowing the formation of the penetrating jet are very narrow. It is concluded that the liquid jet induced by the bubble interactions resulted from the collapse and the rebound of the smaller bubble nearby the bigger bubble. This is defined as the "catapult effect." Such a directional liquid transportation is a promising tool as a micro-injector or a micro-pump. The investigation results could be also supplementary to the understandings of the bubble dynamics.

In Search of the Big Bubble

ERIC Educational Resources Information Center

Simoson, Andrew; Wentzky, Bethany

2011-01-01

Freely rising air bubbles in water sometimes assume the shape of a spherical cap, a shape also known as the "big bubble". Is it possible to find some objective function involving a combination of a bubble's attributes for which the big bubble is the optimal shape? Following the basic idea of the definite integral, we define a bubble's surface as…

A note on effects of rational bubble on portfolios

NASA Astrophysics Data System (ADS)

Wang, Chan; Nie, Pu-yan

2018-02-01

In general, demand increases in wealth and decreases in price in microeconomics. We thereby propose a completely different perspective. By establishing expected utility function of investors, this article introduces one rational bubble asset and one bubble free asset in portfolios and focuses on the effects of bubble on investment portfolios from wealth and price perspectives. All conclusions are obtained by theoretical analysis with microeconomics theory. We argue that inferior goods and Giffen behavior can occur for the bubble free asset in microeconomic fields. The results can help investors to recognize bubble assets and bubble free assets more scientifically. Both bubble and bubble free assets can be inferior goods under some conditions, so we cannot to say which asset better than the other one absolutely.

Characterization of nano-bubbles as an oxygen carrier for in-situ bioremediation of organic pollutants in the subsurface

NASA Astrophysics Data System (ADS)

KIM, E.; Jung, J.; Kang, S.; Choi, Y.

2016-12-01

In-situ bioremediation using bubbles as an oxygen carrier has shown its applicability for aerobic biodegradation of organic pollutants in the subsurface. By recent progresses, generation of nano-sized bubbles is possible, which have enhanced oxygen transfer efficiencies due to their high interfacial area and stability. We are developing an in-situ bioremediation technique using nano-bubbles as an oxygen carrier. In this study, nano-bubbles were characterized for their size and oxygen supply capacity. Nano-bubbles were generated with pure oxygen and pure helium gas. The stable nano-bubbles suspended in water were sonicated to induce the bubbles to coalesce, making them to rise and be released out of the water. By removing the bubbles, the water volume was decreased by 0.006%. The gas released from the bubble suspension was collected to measure the amount of gas in the nano-bubbles. For sparingly soluble helium gas 17.9 mL/L was released from the bubble suspension, while for oxygen 46.2 mL/L was collected. For the oxygen nano-bubble suspension, it is likely that the release of dissolved oxygen (DO) contributed to the collected gas volume. After removing the oxygen nano-bubbles, 36.0 mg/L of DO was still present in water. Altogether, the oxygen nano-bubble suspension was estimated to have 66.2 mg/L of oxygen in a dissolved form and 25.6 mg/L as nano-bubbles. A high DO level in the water was possible because of their large Laplace pressure difference across the fluid interface. Applying Young-Laplace equation and ideal gas law, the bubble diameter was estimated to be approximately 10 nm, having an internal pressure of 323 atm. Considering the saturation DO of 8.26 mg/L for water in equilibrium with the atmosphere, the total oxygen content of 91.8 mg/L in the nano-bubble suspension suggests its great potential as an oxygen carrier. Studies are underway to verify the enhanced aerobic biodegradation of organic pollutants in soils by injecting nano-bubble suspensions.

Dynamics of Vapour Bubbles in Nucleate Boiling. 2; Evolution of Thermally Controlled Bubbles

NASA Technical Reports Server (NTRS)

Buyevich, Yu A.; Webbon, Bruce W.; Callaway, Robert (Technical Monitor)

1995-01-01

The previously developed dynamic theory of growth and detachment of vapour bubbles under conditions of nucleate pool boiling is applied to study motion and deformation of a bubble evolving at a single nucleation site. The bubble growth is presumed to be thermally controlled, and two components of heat transfer to the bubble are accounted of: the one from the bulk of surrounding liquid and the one due to heat conduction across a liquid microlayer formed underneath the bubble. Bubble evolution is governed by the buoyancy and an effective surface tension force, both the forces making the bubble centre of mass move away from the wall and, thus, assisting its detachment. Buoyancy-controlled and surface-tension-controlled regimes are considered separately in a meticulous way. The duration of the whole process of bubble evolution till detachment, the rate of growth, and the bubble departure size are found as functions of time and physical and operating parameters. Some repeatedly observed phenomena, such as an influence of gravity on the growth rate, are explained. Inferences of the model agree qualitatively with available experimental evidence, and conclusions pertaining to the dependence on gravity of the bubble radius at detachment and the whole time of the bubble development when being attached to the wall are confirmed quantitatively.

Review—Physicochemical hydrodynamics of gas bubbles in two phase electrochemical systems

PubMed Central

Taqieddin, Amir; Nazari, Roya; Rajic, Ljiljana; Alshawabkeh, Akram

2018-01-01

Electrochemical systems suffer from poor management of evolving gas bubbles. Improved understanding of bubbles behavior helps to reduce overpotential, save energy and enhance the mass transfer during chemical reactions. This work investigates and reviews the gas bubbles hydrodynamics, behavior, and management in electrochemical cells. Although the rate of bubble growth over the electrode surface is well understood, there is no reliable prediction of bubbles break-off diameter from the electrode surface because of the complexity of bubbles motion near the electrode surface. Particle Image Velocimetry (PIV) and Laser Doppler Anemometry (LDA) are the most common experimental techniques to measure bubble dynamics. Although the PIV is faster than LDA, both techniques are considered expensive and time-consuming. This encourages adapting Computational Fluid Dynamics (CFD) methods as an alternative to study bubbles behavior. However, further development of CFD methods is required to include coalescence and break-up of bubbles for better understanding and accuracy. The disadvantages of CFD methods can be overcome by using hybrid methods. The behavior of bubbles in electrochemical systems is still a complex challenging topic which requires a better understanding of the gas bubbles hydrodynamics and their interactions with the electrode surface and bulk liquid, as well as between the bubbles itself. PMID:29731515

Bubble pinch-off and scaling during liquid drop impact on liquid pool

NASA Astrophysics Data System (ADS)

Ray, Bahni; Biswas, Gautam; Sharma, Ashutosh

2012-08-01

Simulations are performed to show entrapment of air bubble accompanied by high speed upward and downward water jets when a water drop impacts a pool of water surface. A new bubble entrapment zone characterised by small bubble pinch-off and long thick jet is found. Depending on the bubble and jet behaviour, the bubble entrapment zone is subdivided into three sub-regimes. The entrapped bubble size and jet height depends on the crater shape and its maximum depth. During the bubble formation, bubble neck develops an almost singular shape as it pinches off. The final pinch-off shape and the power law governing the pinching, rneck ∝ A(t0 - t)αvaries with the Weber number. Weber dependence of the function describing the radius of the bubble during the pinch-off only affects the coefficient A and not the power exponent α.

CB Radios

ERIC Educational Resources Information Center

Martin, Dick

1977-01-01

Citizen band radios keep trucking across the American scene, and no doubt your students are caught in the folk craze. Provides some suggestions for channeling students' interests with a unit on CBs. (Author/RK)

Comparative genomics provides new insights into the diversity, physiology, and sexuality of the only industrially exploited tremellomycete: Phaffia rhodozyma

DOE PAGES

Bellora, Nicolas; Moline, Martin; David-Palma, Marcia; ...

2016-11-09

The class Tremellomycete (Agaricomycotina) encompasses more than 380 fungi. Although there are a few edible Tremella spp., the only species with current biotechnological use is the astaxanthin-producing yeast Phaffia rhodozyma (Cystofilobasidiales). Besides astaxanthin, a carotenoid pigment with potent antioxidant activity and great value for aquaculture and pharmaceutical industries, P. rhodozyma possesses multiple exceptional traits of fundamental and applied interest. The aim of this study was to obtain, and analyze two new genome sequences of representative strains from the northern (CBS 7918 T, the type strain) and southern hemispheres (CRUB 1149) and compre them to a previously published genome sequence (strainmore » CBS 6938). Furthermore, photoprotection and antioxidant related genes, as well as genes involved in sexual reproduction were analyzed.« less

Draft genome sequences of the oomycete Pythium insidiosum strain CBS 573.85 from a horse with pythiosis and strain CR02 from the environment.

PubMed

Patumcharoenpol, Preecha; Rujirawat, Thidarat; Lohnoo, Tassanee; Yingyong, Wanta; Vanittanakom, Nongnuch; Kittichotirat, Weerayuth; Krajaejun, Theerapong

2018-02-01

Pythium insidiosum is an aquatic oomycete microorganism that causes the fatal infectious disease, pythiosis, in humans and animals. The organism has been successfully isolated from the environment worldwide. Diagnosis and treatment of pythiosis is difficult and challenging. Genome sequences of P. insidiosum , isolated from humans, are available and accessible in public databases. To further facilitate biology-, pathogenicity-, and evolution-related genomic and genetic studies of P. insidiosum , we report two additional draft genome sequences of the P. insidiosum strain CBS 573.85 (35.6 Mb in size; accession number, BCFO00000000.1) isolated from a horse with pythiosis, and strain CR02 (37.7 Mb in size; accession number, BCFR00000000.1) isolated from the environment.

Comparative genomics provides new insights into the diversity, physiology, and sexuality of the only industrially exploited tremellomycete: Phaffia rhodozyma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bellora, Nicolas; Moline, Martin; David-Palma, Marcia

The class Tremellomycete (Agaricomycotina) encompasses more than 380 fungi. Although there are a few edible Tremella spp., the only species with current biotechnological use is the astaxanthin-producing yeast Phaffia rhodozyma (Cystofilobasidiales). Besides astaxanthin, a carotenoid pigment with potent antioxidant activity and great value for aquaculture and pharmaceutical industries, P. rhodozyma possesses multiple exceptional traits of fundamental and applied interest. The aim of this study was to obtain, and analyze two new genome sequences of representative strains from the northern (CBS 7918 T, the type strain) and southern hemispheres (CRUB 1149) and compre them to a previously published genome sequence (strainmore » CBS 6938). Furthermore, photoprotection and antioxidant related genes, as well as genes involved in sexual reproduction were analyzed.« less

Nitrile bioconversion by Microbacterium imperiale CBS 498-74 resting cells in batch and ultrafiltration membrane bioreactors.

PubMed

Cantarella, M; Cantarella, L; Gallifuoco, A; Spera, A

2006-03-01

The biohydration of acrylonitrile, propionitrile and benzonitrile catalysed by the NHase activity contained in resting cells of Microbacterium imperiale CBS 498-74 was operated at 5, 10 and 20 degrees C in laboratory-scale batch and membrane bioreactors. The bioreactions were conducted in buffered medium (50 mM Na(2)HPO(4)/NaH(2)PO(4), pH 7.0) in the presence of distilled water or tap-water, to simulate a possible end-pipe biotreatment process. The integral bioreactor performances were studied with a cell loading (dry cell weight; DCW) varying from 0.1 mg(DCW) per reactor to 16 mg(DCW) per reactor, in order to realize near 100% bioconversion of acrylonitrile, propionitrile and benzonitrile without consistent loss of NHase activity.

Phenylalanyl-Glycyl-Phenylalanine Tripeptide: A Model System for Aromatic-Aromatic Side Chain Interactions in Proteins

DOE Office of Scientific and Technical Information (OSTI.GOV)

Valdes, Haydee; Pluhackova, Kristyna; Hobza, Pavel

The performance of a wide range of quantum chemical calculations for the ab initio study of realistic model systems of aromatic-aromatic side chain interactions in proteins (in particular those π-π interactions occurring between adjacent residues along the protein sequence) is here assessed on the phenylalanyl-glycyl-phenylalanine (FGF) tripeptide. Energies and geometries obtained at different levels of theory are compared with CCSD(T)/CBS benchmark energies and RI-MP2/cc-pVTZ benchmark geometries, respectively. Consequently, a protocol of calculation alternative to the very expensive CCSD(T)/CBS is proposed. In addition to this, the preferred orientation of the Phe aromatic side chains is discussed and compared with previous resultsmore » on the topic.« less

Inorganic Corrosion-Inhibitive Pigments for High-Temperature Alkali-activated Well Casing Foam Cement

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sugama, T.; Pyatina, T.

2014-11-01

This study evaluates inorganic pigments for improving carbon steel (CS) brine-corrosion protection by the sodium metasilicate-activated calcium aluminate cement/Fly Ash blend at 300°C. Calcium borosilicate (CBS) and zinc phosphate, significantly improved CS corrosion-protection by decreasing cement’s permeability for corrosive ions and inhibiting anodic corrosion. An amorphous Na 2O-Al 2O 3-SiO 2-H 2O phase tightly attached to CS surface formed at 300oC in CBS-modified cement pore solution. The corrosion rate of the CS covered with this phase was nearly 4-fold lower than in the case of nonmodified cement pore solution where the major phase formed on the surface of CS wasmore » crystalline analcime.« less

Inorganic Corrosion-Inhibitive Pigments for High-Temperature Alkali-activated Well Casing Foam Cement

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sugama, T.; Pyatina, T.

2014-11-14

This study evaluates inorganic pigments for improving carbon steel (CS) brine-corrosion protection by the sodium metasilicate-activated calcium aluminate cement/Fly Ash blend at 300°C. Calcium borosilicate (CBS) and zinc phosphate, significantly improved CS corrosion-protection by decreasing cement’s permeability for corrosive ions and inhibiting anodic corrosion. An amorphous Na 2O-Al 2O 3-SiO 2-H 2O phase tightly attached to CS surface formed at 300oC in CBS-modified cement pore solution. The corrosion rate of the CS covered with this phase was nearly 4-fold lower than in the case of nonmodified cement pore solution where the major phase formed on the surface of CS wasmore » crystalline analcime.« less

How 60 Minutes ticked off Illinois Power

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1980-04-01

A November 60 Minutes broadcast on CBS television asserting that costs are out of control at the Illinois Power Co's(IP) Clinton nuclear power project because of management incompetence triggered a series of rebuttals and counter-rebuttals. A review of the events and correspondence during the planning stage and after the broadcast explores the question of construction cost overruns and the economic impact the broadcast had on IP's investors, employees, and customers. A parallel filming by IP was aired to show how the CBS edited the interview with IP officials. IP personnel feel betrayed by what they consider misconceptions and errors inmore » the broadcast and are unhappy that an employee morale problem was worsened. Counter-arguments by both parties indicate a disagreement on both facts and interpretations. (DCK)« less

Polychlorinated biphenyl concentrations, congener profiles, and ratios in the fat tissue, eggs, and plasma of snapping turtles (Chelydra s. serpentina) from the Ohio Basin of Lake Erie, USA.

PubMed

Dabrowska, H; Fisher, S W; Estenik, J; Kidekhel, R; Stromberg, P

2006-08-01

Concentrations and profiles of polychlorinated biphenyls (PCBs) were determined in three tissues of adult snapping turtles (Chelydra serpentina serpentina) from six locations in the Ohio Basin of Lake Erie to characterize tissue variation and geographic trends. The locations included the Ohio Areas of Concern, i.e., the Ashtabula, Black, and Maumee Rivers; the Ottawa River near Toledo; and two reference sites. Mean total PCBs were greatest in turtles from the Ottawa River followed by the Maumee, Ashtabula, and Black Rivers. All three types of samples-fat tissue (FT), eggs, and plasma-showed the same geographic trend in PCB levels. On a wet-weight basis, mean concentrations ranged from 2,148 to 18,669 ng/g in FT, from 183 to 3,683 ng/g in eggs, and from 18 to 201 ng/g in plasma. Across all sites, total PCB concentrations between the tissues were significantly correlated (0.001 < p < 0.005; Pearson correlation coefficient (r ( P )) was between 0.720 and 0.954). Two distinctly different profiles with respect to relative congener and homologue concentrations were found among the sites. One that included four of the six sites examined was characterized by hexa-chlorobiphenyl (hexa-CB) dominance followed by hepta-CBs, with PCBs no. 138 + 163, 153 + 132 + 105, and 180 being the most abundant congeners. The second profile, specific for turtles from the Ottawa River, was different from the first in that tetra-CBs were the most abundant congeners followed by hexa-CBs. Analysis of variance (ANOVA) indicated significant intertissue differences in the PCB homologue profiles, i.e., FT had a higher percentage of hepta-, octa-, and nona-CBs compared with eggs and plasma, whereas eggs showed a higher percentage of hexa-CBs. At any listed location, FT, eggs, and plasma had the same congener profile. An intertissue distribution of lipid-normalized individual congener concentrations examined by regression analyses revealed significant egg-FT, egg-plasma, and FT-plasma relations for >40 congeners (0.001 < p < 0.05). The distribution ratios determined for these congeners from the slope of the regression lines averaged 1.235 +/- 0.279, 0.430 +/- 0.170, and 0.387 +/- 0.115, respectively. The plasma wet weight-FT lipid-normalized concentration ratios for these congeners averaged 0.012 +/- 0.006. Both egg-FT and plasma wet weight-FT lipid-normalized ratios regressed against log K(ow) showed significant decreases, with increasing log K(ow), indicating greater accumulation of highly chlorinated congeners in FT than in other compartments. The estimated 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalents ranged from 0.007 ng/g at reference sites to 0.060 ng/g at contaminated sites and from 0.099 to 1.992 ng/g in plasma and eggs, respectively. In both plasma and eggs, coplanar-CBs were the major contributors to total toxic equivalents (TEQs). Eggs from all contaminated sites had TEQs that exceeded the lowest observed effect level TEQs proposed for bald eagle chicks, in addition to high SigmaPCB levels at some of these sites, especially the Ottawa and Maumee River sites, indicate potentially increased risk to turtles and possibly other wildlife species inhabiting these ecosystems. Significant correlations of total PCBs and individual congeners between FT, eggs, and plasma indicate that blood sampling can provide a good nonlethal measure of PCB exposure and can be used to monitor environmental contamination.

Bubble velocity, diameter, and void fraction measurements in a multiphase flow using fiber optic reflectometer

NASA Astrophysics Data System (ADS)

Lim, Ho-Joon; Chang, Kuang-An; Su, Chin B.; Chen, Chi-Yueh

2008-12-01

A fiber optic reflectometer (FOR) technique featuring a single fiber probe is investigated for its feasibility of measuring the bubble velocity, diameter, and void fraction in a multiphase flow. The method is based on the interference of the scattered signal from the bubble surface with the Fresnel reflection signal from the tip of the optical fiber. Void fraction is obtained with a high accuracy if an appropriate correction is applied to compensate the underestimated measurement value. Velocity information is accurately obtained from the reflected signals before the fiber tip touches the bubble surface so that several factors affecting the traditional dual-tip probes such as blinding, crawling, and drifting effects due to the interaction between the probe and bubbles can be prevented. The coherent signals reflected from both the front and rear ends of a bubble can provide velocity information. Deceleration of rising bubbles and particles due to the presence of the fiber probe is observed when they are very close to the fiber tip. With the residence time obtained, the bubble chord length can be determined by analyzing the coherent signal for velocity determination before the deceleration starts. The bubble diameters are directly obtained from analyzing the signals of the bubbles that contain velocity information. The chord lengths of these bubbles measured by FOR represent the bubble diameters when the bubble shape is spherical or represent the minor axes when the bubble shape is ellipsoidal. The velocity and size of bubbles obtained from the FOR measurements are compared with those obtained simultaneously using a high speed camera.

Wall Area of Influence and Growing Wall Heat Transfer due to Sliding Bubbles in Subcooled Boiling Flow

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yoo, Junsoo; Estrada-Perez, Carlos E.; Hassan, Yassin A.

A variety of dynamical features of sliding bubbles and their impact on wall heat transfer were observed at subcooled flow boiling conditions in a vertical square test channel. Among the wide range of parameters observed, we particularly focus in this paper on (i) the sliding bubbles’ effect on wall heat transfer (supplemantry discussion to the authors’ previous work in Yoo et al. (2016a,b)) and (ii) the wall area influenced by sliding bubbles in subcooled boiling flow. At first, this study reveals that the degree of wall heat transfer improvement due to sliding bubbles depended less on the wall superheat conditionmore » as the mass flux increased. Also, the sliding bubble trajectory was found to be one of the critical factors in order to properly describe the wall heat transfer associated with sliding bubbles. In particular, the wall area influenced by sliding bubbles depended strongly on both sliding bubble trajectory and sliding bubble size; the sliding bubble trajectory was also observed to be closely related to the sliding bubble size. Importantly, these results indicate the limitation of current approach in CFD analyses especially for the wall area of bubble influence. In addition, the analyses on the temporal fraction of bubbles’ residence (FR) along the heated wall show that the sliding bubbles typically travel through narrow path with high frequency while the opposite was observed downstream. That is, both FR and sliding bubble trajectory depended substantially on the distance from nucleation site, which is expected to be similar for the quenching heat transfer mode induced by sliding bubbles.« less

Void fraction, bubble size and interfacial area measurements in co-current downflow bubble column reactor with microbubble dispersion

DOE PAGES

Hernandez-Alvarado, Freddy; Kalaga, Dinesh V.; Turney, Damon; ...

2017-05-06

Micro-bubbles dispersed in bubble column reactors have received great interest in recent years, due to their small size, stability, high gas-liquid interfacial area concentrations and longer residence times. The high gas-liquid interfacial area concentrations lead to high mass transfer rates compared to conventional bubble column reactors. In the present work, experiments have been performed in a down-flow bubble column reactor with micro-bubbles generated and dispersed by a novel mechanism to determine the gas-liquid interfacial area concentrations by measuring the void fraction and bubble size distributions. Gamma-ray densitometry has been employed to determine the axial and radial distributions of void fractionmore » and a high speed camera equipped with a borescope is used to measure the axial and radial variations of bubble sizes. Also, the effects of superficial gas and liquid velocities on the two-phase flow characteristics have been investigated. Further, reconstruction techniques of the radial void fraction profiles from the gamma densitometry's chordal measurements are discussed and compared for a bubble column reactor with dispersed micro-bubbles. The results demonstrate that the new bubble generation technique offers high interfacial area concentrations (1,000 to 4,500 m 2/m 3) with sub-millimeter bubbles (500 to 900 µm) and high overall void fractions (10% – 60%) in comparison with previous bubble column reactor designs. The void fraction data was analyzed using slip velocity model and empirical correlation has been proposed to predict the Sauter mean bubble diameter.« less

Interaction of lithotripter shockwaves with single inertial cavitation bubbles

PubMed Central

Klaseboer, Evert; Fong, Siew Wan; Turangan, Cary K.; Khoo, Boo Cheong; Szeri, Andrew J.; Calvisi, Michael L.; Sankin, Georgy N.; Zhong, Pei

2008-01-01

The dynamic interaction of a shockwave (modelled as a pressure pulse) with an initially spherically oscillating bubble is investigated. Upon the shockwave impact, the bubble deforms non-spherically and the flow field surrounding the bubble is determined with potential flow theory using the boundary-element method (BEM). The primary advantage of this method is its computational efficiency. The simulation process is repeated until the two opposite sides of the bubble surface collide with each other (i.e. the formation of a jet along the shockwave propagation direction). The collapse time of the bubble, its shape and the velocity of the jet are calculated. Moreover, the impact pressure is estimated based on water-hammer pressure theory. The Kelvin impulse, kinetic energy and bubble displacement (all at the moment of jet impact) are also determined. Overall, the simulated results compare favourably with experimental observations of lithotripter shockwave interaction with single bubbles (using laser-induced bubbles at various oscillation stages). The simulations confirm the experimental observation that the most intense collapse, with the highest jet velocity and impact pressure, occurs for bubbles with intermediate size during the contraction phase when the collapse time of the bubble is approximately equal to the compressive pulse duration of the shock wave. Under this condition, the maximum amount of energy of the incident shockwave is transferred to the collapsing bubble. Further, the effect of the bubble contents (ideal gas with different initial pressures) and the initial conditions of the bubble (initially oscillating vs. non-oscillating) on the dynamics of the shockwave–bubble interaction are discussed. PMID:19018296

Interaction of lithotripter shockwaves with single inertial cavitation bubbles.

PubMed

Klaseboer, Evert; Fong, Siew Wan; Turangan, Cary K; Khoo, Boo Cheong; Szeri, Andrew J; Calvisi, Michael L; Sankin, Georgy N; Zhong, Pei

2007-01-01

The dynamic interaction of a shockwave (modelled as a pressure pulse) with an initially spherically oscillating bubble is investigated. Upon the shockwave impact, the bubble deforms non-spherically and the flow field surrounding the bubble is determined with potential flow theory using the boundary-element method (BEM). The primary advantage of this method is its computational efficiency. The simulation process is repeated until the two opposite sides of the bubble surface collide with each other (i.e. the formation of a jet along the shockwave propagation direction). The collapse time of the bubble, its shape and the velocity of the jet are calculated. Moreover, the impact pressure is estimated based on water-hammer pressure theory. The Kelvin impulse, kinetic energy and bubble displacement (all at the moment of jet impact) are also determined. Overall, the simulated results compare favourably with experimental observations of lithotripter shockwave interaction with single bubbles (using laser-induced bubbles at various oscillation stages). The simulations confirm the experimental observation that the most intense collapse, with the highest jet velocity and impact pressure, occurs for bubbles with intermediate size during the contraction phase when the collapse time of the bubble is approximately equal to the compressive pulse duration of the shock wave. Under this condition, the maximum amount of energy of the incident shockwave is transferred to the collapsing bubble. Further, the effect of the bubble contents (ideal gas with different initial pressures) and the initial conditions of the bubble (initially oscillating vs. non-oscillating) on the dynamics of the shockwave-bubble interaction are discussed.

Void fraction, bubble size and interfacial area measurements in co-current downflow bubble column reactor with microbubble dispersion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hernandez-Alvarado, Freddy; Kalaga, Dinesh V.; Turney, Damon

Micro-bubbles dispersed in bubble column reactors have received great interest in recent years, due to their small size, stability, high gas-liquid interfacial area concentrations and longer residence times. The high gas-liquid interfacial area concentrations lead to high mass transfer rates compared to conventional bubble column reactors. In the present work, experiments have been performed in a down-flow bubble column reactor with micro-bubbles generated and dispersed by a novel mechanism to determine the gas-liquid interfacial area concentrations by measuring the void fraction and bubble size distributions. Gamma-ray densitometry has been employed to determine the axial and radial distributions of void fractionmore » and a high speed camera equipped with a borescope is used to measure the axial and radial variations of bubble sizes. Also, the effects of superficial gas and liquid velocities on the two-phase flow characteristics have been investigated. Further, reconstruction techniques of the radial void fraction profiles from the gamma densitometry's chordal measurements are discussed and compared for a bubble column reactor with dispersed micro-bubbles. The results demonstrate that the new bubble generation technique offers high interfacial area concentrations (1,000 to 4,500 m 2/m 3) with sub-millimeter bubbles (500 to 900 µm) and high overall void fractions (10% – 60%) in comparison with previous bubble column reactor designs. The void fraction data was analyzed using slip velocity model and empirical correlation has been proposed to predict the Sauter mean bubble diameter.« less

Time-Dependent Changes in a Shampoo Bubble

NASA Astrophysics Data System (ADS)

Chattopadhyay, Arun

2000-10-01

This article demonstrates the fascinating phenomenon of time evolution of a shampoo bubble through experiments that can be performed by undergraduate students. The changes in thickness of the bubble films with time are followed by UV-vis spectroscopy. The change in chemical composition as a bubble film evolves is monitored by FTIR spectroscopy. It is observed that the change in thickness of a typical shampoo bubble film enclosed in a container is gradual and slow, and the hydrocarbon components of the bubble drain from the bubble much more slowly than water. An additional agent, such as acetonitrile, strikingly alters the dynamics of evolution of such a bubble.

Effect of electrolytes on bubble coalescence in columns observed with visualization techniques.

PubMed

Aguilera, María Eugenia; Ojeda, Antonieta; Rondón, Carolina; López De Ramos, Aura

2002-10-01

Bubble coalescence and the effect of electrolytes on this phenomenon have been previously studied. This interfacial phenomenon has attracted attention for reactor design/operation and enhanced oil recovery. Predicting bubble coalescence may help prevent low yields in reactors and predict crude oil recovery. Because of the importance of bubble coalescence, the objectives of this work were to improve the accuracy of measuring the percentage of coalescing bubbles and to observe the interfacial gas-liquid behavior. An experimental setup was designed and constructed. Bubble interactions were monitored with a visualization setup. The percentage of air bubble coalescence was 100% in distilled water, about 50% in 0.1 M sodium chloride (NaCl) aqueous solution, and 0% in 0.145 M NaCl aqueous solution. A reduction of the contact gas-liquid area was observed in distillate water. The volume of the resulting bubble was the sum of the original bubble volumes. Repulsion of bubbles was observed in NaCl solutions exceeding 0.07 M. The percentage of bubble coalescence diminishes as the concentration of NaCl chloride increases. High-speed video recording is an accurate technique to measure the percentage of bubble coalescence, and represents an important advance in gas-liquid interfacial studies.

Two-Dimensional Numerical Simulations of Ultrasound in Liquids with Gas Bubble Agglomerates: Examples of Bubbly-Liquid-Type Acoustic Metamaterials (BLAMMs)

PubMed Central

Vanhille, Christian

2017-01-01

This work deals with a theoretical analysis about the possibility of using linear and nonlinear acoustic properties to modify ultrasound by adding gas bubbles of determined sizes in a liquid. We use a two-dimensional numerical model to evaluate the effect that one and several monodisperse bubble populations confined in restricted areas of a liquid have on ultrasound by calculating their nonlinear interaction. The filtering of an input ultrasonic pulse performed by a net of bubbly-liquid cells is analyzed. The generation of a low-frequency component from a single cell impinged by a two-frequency harmonic wave is also studied. These effects rely on the particular dispersive character of attenuation and nonlinearity of such bubbly fluids, which can be extremely high near bubble resonance. They allow us to observe how gas bubbles can change acoustic signals. Variations of the bubbly medium parameters induce alterations of the effects undergone by ultrasound. Results suggest that acoustic signals can be manipulated by bubbles. This capacity to achieve the modification and control of sound with oscillating gas bubbles introduces the concept of bubbly-liquid-based acoustic metamaterials (BLAMMs). PMID:28106748

Repeated bubble breakup and coalescence in perturbed Hele-Shaw channels

NASA Astrophysics Data System (ADS)

Thompson, Alice; Franco-Gomez, Andres; Hazel, Andrew; Juel, Anne

2017-11-01

The introduction of an axially-uniform, centred constriction in a Hele-Shaw channel leads to multiple propagation modes for both air fingers and bubbles, including symmetric and asymmetric steadily propagating modes along with oscillations. These multiple modes correspond to a non-trivial bifurcation structure, and relate to the plethora of steadily propagating bubbles and fingers which exist in the Saffman-Taylor system. In both experiments and depth-averaged computations, a very small centred occlusion can be enough to trigger bubble breakup, with a single large centred bubble splitting into two smaller bubbles which propagate along each side of the channel. We present numerical simulations for the depth-averaged model, implementing geometric criteria for pinchoff and coalescence in order to track the bubble before and beyond breakup. We find that the two-bubble state is itself unstable, with finger competition causing one bubble to move ahead; the trailing bubble then moves across the channel to merge with the leading bubble. However, the story is not always so simple, enabling complicated cascades of splitting and merging bubbles. We compare the general dynamical behaviour, basins of attraction, and the details of merging and splitting, to experimental observations.

Odds of observing the multiverse

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dahlen, A.

2010-03-15

Eternal inflation predicts that our observable universe lies within a bubble (or pocket universe) embedded in a volume of inflating space. The interior of the bubble undergoes inflation and standard cosmology, while the bubble walls expand outward and collide with other neighboring bubbles. The collisions provide either an opportunity to make a direct observation of the multiverse or, if they produce unacceptable anisotropy, a threat to inflationary theory. The probability of an observer in our bubble detecting the effects of collisions has an absolute upper bound set by the odds of being in the part of our bubble that liesmore » in the forward light cone of a collision; in the case of collisions with bubbles of identical vacua, this bound is given by the bubble nucleation rate times (H{sub O}/H{sub I}){sup 2}, where H{sub O} is the Hubble scale outside the bubbles and H{sub I} is the scale of the second round of inflation that occurs inside our bubble. Similar results were obtained by Freigovel et al. using a different method for the case of collisions with bubbles of much larger cosmological constant; here, it is shown to hold in the case of collisions with identical bubbles as well.« less

Observations of the collapses and rebounds of millimeter-sized lithotripsy bubbles

PubMed Central

Kreider, Wayne; Crum, Lawrence A.; Bailey, Michael R.; Sapozhnikov, Oleg A.

2011-01-01

Bubbles excited by lithotripter shock waves undergo a prolonged growth followed by an inertial collapse and rebounds. In addition to the relevance for clinical lithotripsy treatments, such bubbles can be used to study the mechanics of inertial collapses. In particular, both phase change and diffusion among vapor and noncondensable gas molecules inside the bubble are known to alter the collapse dynamics of individual bubbles. Accordingly, the role of heat and mass transport during inertial collapses is explored by experimentally observing the collapses and rebounds of lithotripsy bubbles for water temperatures ranging from 20 to 60 °C and dissolved gas concentrations from 10 to 85% of saturation. Bubble responses were characterized through high-speed photography and acoustic measurements that identified the timing of individual bubble collapses. Maximum bubble diameters before and after collapse were estimated and the corresponding ratio of volumes was used to estimate the fraction of energy retained by the bubble through collapse. The rebounds demonstrated statistically significant dependencies on both dissolved gas concentration and temperature. In many observations, liquid jets indicating asymmetric bubble collapses were visible. Bubble rebounds were sensitive to these asymmetries primarily for water conditions corresponding to the most dissipative collapses. PMID:22088027

Inertial collapse of bubble pairs near a solid surface

NASA Astrophysics Data System (ADS)

Alahyari Beig, Shahaboddin; Johnsen, Eric

2017-11-01

Cavitation occurs in a variety of applications ranging from naval structures to biomedical ultrasound. One important consequence is structural damage to neighboring surfaces following repeated inertial collapse of vapor bubbles. Although the mechanical loading produced by the collapse of a single bubble has been widely investigated, less is known about the detailed dynamics of the collapse of multiple bubbles. In such a problem, the bubble-bubble interactions typically affect the dynamics, e.g., by increasing the non-sphericity of the bubbles and amplifying/hindering the collapse intensity depending on the flow parameters. Here, we quantify the effects of bubble-bubble interactions on the bubble dynamics, as well as the pressures/temperatures produced by the collapse of a pair of gas bubbles near a rigid surface. We perform high-resolution simulations of this problem by solving the three-dimensional compressible Navier-Stokes equations for gas/liquid flows. The results are used to investigate the non-spherical bubble dynamics and characterize the pressure and temperature fields based on the relevant parameters entering the problem: stand-off distance, geometrical configuration (angle, relative size, distance), collapse strength. This research was supported in part by ONR Grant N00014-12-1-0751 and NSF Grant CBET 1253157.

Two-Dimensional Numerical Simulations of Ultrasound in Liquids with Gas Bubble Agglomerates: Examples of Bubbly-Liquid-Type Acoustic Metamaterials (BLAMMs).

PubMed

Vanhille, Christian

2017-01-17

This work deals with a theoretical analysis about the possibility of using linear and nonlinear acoustic properties to modify ultrasound by adding gas bubbles of determined sizes in a liquid. We use a two-dimensional numerical model to evaluate the effect that one and several monodisperse bubble populations confined in restricted areas of a liquid have on ultrasound by calculating their nonlinear interaction. The filtering of an input ultrasonic pulse performed by a net of bubbly-liquid cells is analyzed. The generation of a low-frequency component from a single cell impinged by a two-frequency harmonic wave is also studied. These effects rely on the particular dispersive character of attenuation and nonlinearity of such bubbly fluids, which can be extremely high near bubble resonance. They allow us to observe how gas bubbles can change acoustic signals. Variations of the bubbly medium parameters induce alterations of the effects undergone by ultrasound. Results suggest that acoustic signals can be manipulated by bubbles. This capacity to achieve the modification and control of sound with oscillating gas bubbles introduces the concept of bubbly-liquid-based acoustic metamaterials (BLAMMs).

A Study of Bubble and Slug Gas-Liquid Flow in a Microgravity Environment

NASA Technical Reports Server (NTRS)

McQuillen, J.

2000-01-01

The influence of gravity on the two-phase flow dynamics is obvious.As the gravity level is reduced,there is a new balance between inertial and interfacial forces, altering the behavior of the flow. In bubbly flow,the absence of drift velocity leads to spherical-shaped bubbles with a rectilinear trajectory.Slug flow is a succession of long bubbles and liquid slug carrying a few bubbles. There is no flow reversal in the thin liquid film as the long bubble and liquid slug pass over the film. Although the flow structure seems to be simpler than in normal gravity conditions,the models developed for the prediction of flow behavior in normal gravity and extended to reduced gravity flow are unable to predict the flow behavior correctly.An additional benefit of conducting studies in microgravity flows is that these studies aide the development of understanding for normal gravity flow behavior by removing the effects of buoyancy on the shape of the interface and density driven shear flows between the gas and the liquid phases. The proposal calls to study specifically the following: 1) The dynamics of isolated bubbles in microgravity liquid flows will be analyzed: Both the dynamics of spherical isolated bubbles and their dispersion by turbulence, their interaction with the pipe wall,the behavior of the bubbles in accelerated or decelerated flows,and the dynamics of isolated cylindrical bubbles, their deformation in accelerated/decelerated flows (in converging or diverging channels), and bubble/bubble interaction. Experiments will consist of the use of Particle Image Velocimetry (PIV) and Laser Doppler Velocimeters (LDV) to study single spherical bubble and single and two cylindrical bubble behavior with respect to their influence on the turbulence of the surrounding liquid and on the wall 2) The dynamics of bubbly and slug flow in microgravity will be analyzed especially for the role of the coalescence in the transition from bubbly to slug flow (effect of fluid properties and surfactant), to identify clusters that promote coalescence and transition the void fraction distribution in bubbly and slug flow,to measure the wall friction in bubbly flow. These experiments will consist of multiple bubbles type flows and will utilize hot wire and film anemometers to measure liquid velocity and wall shear stress respectively and double fiber optic probes to measure bubble size and velocity as a function of tube radius and axial location.

The Speed of Axial Propagation of a Cylindrical Bubble Through a Cylindrical Vortex

NASA Technical Reports Server (NTRS)

Shariff, Karim; Mansour, Nagi N. (Technical Monitor)

2002-01-01

Inspired by the rapid elongation of air columns injected into vortices by dolphins, we present an exact inviscid solution for the axial speed (assumed steady) of propagation of the tip of a semi-infinite cylindrical bubble along the axis of a cylindrical vortex. The bubble is assumed to be held at constant pressure by being connected to a reservoir, the lungs of the dolphin, say. For a given bubble pressure, there is a modest critical rotation rate above which steadily propagating bubbles exist. For a bubble at ambient pressure, the propagation speed of the bubble (relative to axial velocity within the vortex) varies between 0.5 and 0.6 of the maximum rotational speed of the vortex. Surprisingly, the bubble tip can propagate (almost as rapidly) even when the pressure minimum in the vortex core is greater than the bubble pressure; in this case, solutions exhibit a dimple on the nose of the bubble. A situation important for incipient vortex cavitation, and one which dolphins also demonstrate, is elongation of a free bubble, i.e., one whose internal pressure may vary. Under the assumption that the acceleration term is small (checked a posteriori), the steady solution is applied at each instant during the elongation. Three types of behavior are then possible depending on physical parameters and initial conditions: (A) Unabated elongation with slowly increasing bubble pressure, and nearly constant volume. Volume begins to decrease in the late stages. (B1) Elongation with decreasing bubble pressure. A limit point of the steady solution is encountered at a finite bubble length. (B2) Unabated elongation with decreasing bubble pressure and indefinite creation of volume. This is made possible by the existence of propagating solutions at bubble pressures below the minimum vortex pressure. As the bubble stretches, its radius initially decreases but then becomes constant; this is also observed in experiments on incipient vortex cavitation.

Size distributions of micro-bubbles generated by a pressurized dissolution method

NASA Astrophysics Data System (ADS)

Taya, C.; Maeda, Y.; Hosokawa, S.; Tomiyama, A.; Ito, Y.

2012-03-01

Size of micro-bubbles is widely distributed in the range of one to several hundreds micrometers and depends on generation methods, flow conditions and elapsed times after the bubble generation. Although a size distribution of micro-bubbles should be taken into account to improve accuracy in numerical simulations of flows with micro-bubbles, a variety of the size distribution makes it difficult to introduce the size distribution in the simulations. On the other hand, several models such as the Rosin-Rammler equation and the Nukiyama-Tanazawa equation have been proposed to represent the size distribution of particles or droplets. Applicability of these models to the size distribution of micro-bubbles has not been examined yet. In this study, we therefore measure size distribution of micro-bubbles generated by a pressurized dissolution method by using a phase Doppler anemometry (PDA), and investigate the applicability of the available models to the size distributions of micro-bubbles. Experimental apparatus consists of a pressurized tank in which air is dissolved in liquid under high pressure condition, a decompression nozzle in which micro-bubbles are generated due to pressure reduction, a rectangular duct and an upper tank. Experiments are conducted for several liquid volumetric fluxes in the decompression nozzle. Measurements are carried out at the downstream region of the decompression nozzle and in the upper tank. The experimental results indicate that (1) the Nukiyama-Tanasawa equation well represents the size distribution of micro-bubbles generated by the pressurized dissolution method, whereas the Rosin-Rammler equation fails in the representation, (2) the bubble size distribution of micro-bubbles can be evaluated by using the Nukiyama-Tanasawa equation without individual bubble diameters, when mean bubble diameter and skewness of the bubble distribution are given, and (3) an evaluation method of visibility based on the bubble size distribution and bubble number density is proposed, and the evaluated visibility agrees well with the visibility measured in the upper tank.

4-Repeat Tauopathy Neuroimaging Initiative - Cycle 2

ClinicalTrials.gov

2018-05-01

Corticobasal Degeneration (CBD); Corticobasal Syndrome (CBS); Cortical-basal Ganglionic Degeneration (CBGD); Progressive Supranuclear Palsy (PSP); Nonfluent Variant Primary Progressive Aphasia (nfvPPA); Oligosymptomatic/Variant Progressive Supranuclear Palsy (o/vPSP)

Business Center

EPA Pesticide Factsheets

Learn how to do business with EPA's Clean Air Markets, including registering to use the Emissions Collection and Monitoring Plan System (ECMPS), the CAMD Business System (CBS), and learn how to submit monitored emissions data.

Physical analysis of the process of cavitation in xylem sap.

PubMed

Shen, Fanyi; Gao, Rongfu; Liu, Wenji; Zhang, Wenjie

2002-06-01

Recent studies have confirmed that cavitation in xylem is caused by air bubbles. We analyzed expansion of a preexistent bubble adhering to a crack in a conduit wall and a bubble formed by the passage of air through a pore of a pit membrane, a process known as air seeding. We consider that there are two equilibrium states for a very small air bubble in the xylem: one is temporarily stable with a bubble radius r1 at point s1 on the curve P(r) relating pressure within the bubble (P) with bubble radius (r); the other is unstable with a bubble radius r2 at point s2 on Pr (where r1 < r2). In each equilibrium state, the bubble collapse pressure (2sigma/r, where sigma is surface tension of water) is balanced by the pressure difference across its surface. In the case of a bubble from a crack in a conduit wall, which is initially at point s1, expansion will occur steadily as water potential decreases. The bubble will burst only if the xylem pressure drops below a threshold value. A formula giving the threshold pressure for bubble bursting is proposed. In the case of an air seed entering a xylem conduit through a pore in a pit membrane, its initial radius may be r2 (i.e., the radius of the pore by which the air seed entered the vessel) at point s2 on Pr. Because the bubble is in an unstable equilibrium when entering the conduit, it can either expand or contract to point s1. As water vaporizes into the air bubble at s2, P rises until it exceeds the gas pressure that keeps the bubble in equilibrium, at which point the bubble will burst and induce a cavitation event in accordance with the air-seeding hypothesis. However, other possible perturbations could make the air-seeded bubble contract to s1, in which case the bubble will burst at a threshold pressure proposed for a bubble expanding from a crack in a conduit wall. For this reason some cavitation events may take place at a xylem threshold pressure (Pl'*) other than that determined by the formula, Plp'* = -2sigma/rp, proposed by Sperry and Tyree (1988), which is applicable only to air-seeded bubbles at s2. The more general formula we propose for calculating the threshold pressure for bubble breaking is consistent with the results of published experiments.

Modeling quiescent phase transport of air bubbles induced by breaking waves

NASA Astrophysics Data System (ADS)

Shi, Fengyan; Kirby, James T.; Ma, Gangfeng

Simultaneous modeling of both the acoustic phase and quiescent phase of breaking wave-induced air bubbles involves a large range of length scales from microns to meters and time scales from milliseconds to seconds, and thus is computational unaffordable in a surfzone-scale computational domain. In this study, we use an air bubble entrainment formula in a two-fluid model to predict air bubble evolution in the quiescent phase in a breaking wave event. The breaking wave-induced air bubble entrainment is formulated by connecting the shear production at the air-water interface and the bubble number intensity with a certain bubble size spectra observed in laboratory experiments. A two-fluid model is developed based on the partial differential equations of the gas-liquid mixture phase and the continuum bubble phase, which has multiple size bubble groups representing a polydisperse bubble population. An enhanced 2-DV VOF (Volume of Fluid) model with a k - ɛ turbulence closure is used to model the mixture phase. The bubble phase is governed by the advection-diffusion equations of the gas molar concentration and bubble intensity for groups of bubbles with different sizes. The model is used to simulate air bubble plumes measured in laboratory experiments. Numerical results indicate that, with an appropriate parameter in the air entrainment formula, the model is able to predict the main features of bubbly flows as evidenced by reasonable agreement with measured void fraction. Bubbles larger than an intermediate radius of O(1 mm) make a major contribution to void fraction in the near-crest region. Smaller bubbles tend to penetrate deeper and stay longer in the water column, resulting in significant contribution to the cross-sectional area of the bubble cloud. An underprediction of void fraction is found at the beginning of wave breaking when large air pockets take place. The core region of high void fraction predicted by the model is dislocated due to use of the shear production in the algorithm for initial bubble entrainment. The study demonstrates a potential use of an entrainment formula in simulations of air bubble population in a surfzone-scale domain. It also reveals some difficulties in use of the two-fluid model for predicting large air pockets induced by wave breaking, and suggests that it may be necessary to use a gas-liquid two-phase model as the basic model framework for the mixture phase and to develop an algorithm to allow for transfer of discrete air pockets to the continuum bubble phase. A more theoretically justifiable air entrainment formulation should be developed.

Study of bubble behavior in weightlessness (effects of thermal gradient and acoustic stationary wave) (M-16)

NASA Technical Reports Server (NTRS)

Azuma, H.

1993-01-01

The aim of this experiment is to understand how bubbles behave in a thermal gradient and acoustic stationary wave under microgravity. In microgravity, bubble or bubbles in a liquid will not rise upward as they do on Earth but will rest where they are formed because there exists no gravity-induced buoyancy. We are interested in how bubbles move and in the mechanisms which support the movement. We will try two ways to make bubbles migrate. The first experiment concerns behavior of bubbles in a thermal gradient. It is well known than an effect of surface tension which is masked by gravity on the ground becomes dominant in microgravity. The surface tension on the side of the bubble at a lower temperature is stronger than at a higher temperature. The bubble migrates toward the higher temperature side due to the surface tension difference. The migration speed depends on the so-called Marangoni number, which is a function of the temperature difference, the bubble diameter, liquid viscosity, and thermal diffusivity. At present, some experimental data about migration speeds in liquids with very small Marangoni numbers were obtained in space experiments, but cases of large Marangoni number are rarely obtained. In our experiment a couple of bubbles are to be injected into a cell filled with silicon oil, and the temperature gradient is to be made gradually in the cell by a heater and a cooler. We will be able to determine migration speeds in a very wide range of Marangoni numbers, as well as study interactions between the bubbles. We will observe bubble movements affected by hydrodynamical and thermal interactions, the two kinds of interactions which occur simultaneously. These observation data will be useful for analyzing the interactions as well as understanding the behavior of particles or drops in materials processing. The second experiment concerns bubble movement in an acoustic stationary wave. It is known that a bubble in a stationary wave moves toward the node or the loop according to whether its diameter is larger or smaller than that of the main resonant radius. In our experiment fine bubbles will be observed to move according to an acoustic field formed in a cylindrical cell. The existence of bubbles varies the acoustic speed, and the interactive force between bubbles will make the bubble behavior collective and complicated. This experiment will be very useful to development of bubble removable technology as well as to the understanding of bubble behavior.

Soap bubbles in paintings: Art and science

NASA Astrophysics Data System (ADS)

Behroozi, F.

2008-12-01

Soap bubbles became popular in 17th century paintings and prints primarily as a metaphor for the impermanence and fragility of life. The Dancing Couple (1663) by the Dutch painter Jan Steen is a good example which, among many other symbols, shows a young boy blowing soap bubbles. In the 18th century the French painter Jean-Simeon Chardin used soap bubbles not only as metaphor but also to express a sense of play and wonder. In his most famous painting, Soap Bubbles (1733/1734) a translucent and quavering soap bubble takes center stage. Chardin's contemporary Charles Van Loo painted his Soap Bubbles (1764) after seeing Chardin's work. In both paintings the soap bubbles have a hint of color and show two bright reflection spots. We discuss the physics involved and explain how keenly the painters have observed the interaction of light and soap bubbles. We show that the two reflection spots on the soap bubbles are images of the light source, one real and one virtual, formed by the curved surface of the bubble. The faint colors are due to thin film interference effects.

Dynamics and noise emission of laser induced cavitation bubbles in a vortical flow field

NASA Astrophysics Data System (ADS)

Oweis, Ghanem F.; Choi, Jaehyug; Ceccio, Steven L.

2004-03-01

The sound produced by the collapse of discrete cavitation bubbles was examined. Laser-generated cavitation bubbles were produced in both a quiescent and a vortical flow. The sound produced by the collapse of the cavitation bubbles was recorded, and its spectral content was determined. It was found that the risetime of the sound pulse produced by the collapse of single, spherical cavitation bubbles in quiescent fluid exceeded that of the slew rate of the hydrophone, which is consistent with previously published results. It was found that, as collapsing bubbles were deformed by the vortical flow, the acoustic impulse of the bubbles was reduced. Collapsing nonspherical bubbles often created a sound pulse with a risetime that exceeded that of the hydrophone slew rate, although the acoustic impulse created by the bubbles was influenced largely by the degree to which the bubbles became nonspherical before collapse. The noise produced by the slow growth of cavitation bubbles in the vortex core was not detectable. These results have implications for the interpretation of hydrodynamic cavitation noise produced by vortex cavitation.

On the effect of irradiation-induced resolution in modelling fission gas release in UO2 LWR fuel

NASA Astrophysics Data System (ADS)

Lösönen, Pekka

2017-12-01

Irradiation resolution of gas atoms and vacancies from intra- and intergranular bubbles in sintered UO2 fuel was studied by comparing macroscopic models with a more mechanistic approach. The applied macroscopic models imply the resolution rate of gas atoms to be proportional to gas concentration in intragranular bubbles and at grain boundary (including intergranular bubbles). A relation was established between the macroscopic models and a single encounter of an energetic fission fragment with a bubble. The effect of bubble size on resolution was quantified. The number of resoluted gas atoms per encounter of a fission fragment per bubble was of the same order of magnitude for intra- and intergranular bubbles. However, the resulting macroscopic resolution rate of gas atoms was about two orders of magnitude larger from intragranular bubbles. The number of vacancies resoluted from a grain face bubble by a passing fission fragment was calculated. The obtained correlations for resolution of gas atoms from intragranular bubbles and grain boundaries and for resolution of vacancies from grain face bubbles were used to demonstrate the effect of irradiation resolution on fission gas release.

Mathematical and experimental modelling of the dynamic bubble processes occurring in a two-phase cyclonic separation device

NASA Astrophysics Data System (ADS)

Schrage, Dean Stewart

1998-11-01

This dissertation presents a combined mathematical and experimental analysis of the fluid dynamics of a gas- liquid, dispersed-phase cyclonic separation device. The global objective of this research is to develop a simulation model of separation process in order to predict the void fraction field within a cyclonic separation device. The separation process is approximated by analyzing the dynamic motion of many single-bubbles, moving under the influence of the far-field, interacting with physical boundaries and other bubbles. The dynamic motion of the bubble is described by treating the bubble as a point-mass and writing an inertial force balance, equating the force applied to the bubble-point-location to the inertial acceleration of the bubble mass (also applied to the point-location). The forces which are applied to the bubble are determined by an integration of the surface pressure over the bubble. The surface pressure is coupled to the intrinsic motion of the bubble, and is very difficult to obtain exactly. However, under moderate Reynolds number, the wake trailing a bubble is small and the near-field flow field can be approximated as an inviscid flow field. Unconventional potential flow techniques are employed to solve for the surface pressure; the hydrodyamic forces are described as a hydrodynamic mass tensor operating on the bubble acceleration vector. The inviscid flow model is augmented with adjunct forces which describe: drag forces, dynamic lift, far-field pressure forces. The dynamic equations of motion are solved both analytically and numerically for the bubble trajectory in specific flow field examples. A validation of these equations is performed by comparing to an experimentally-derived trajectory of a single- bubble, which is released into a cylindrical Couette flow field (inner cylinder rotating) at varying positions. Finally, a simulation of a cyclonic separation device is performed by extending the single-bubble dynamic model to a multi-bubble ensemble. A simplified model is developed to predict the effects of bubble-interaction. The simulation qualitatively depicts the separation physics encountered in an actual cyclonic separation device, supporting the original tenet that the separation process can be approximated by the collective motions of single- bubbles.

Evaluation of stability and size distribution of sunflower oil-coated micro bubbles for localized drug delivery.

PubMed

Filho, Walter Duarte de Araujo; Schneider, Fábio Kurt; Morales, Rigoberto E M

2012-09-20

Micro bubbles were initially introduced as contrast agents for ultrasound examinations as they are able to modify the signal-to-noise ratio in imaging, thus improving the assessment of clinical information on human tissue. Recent developments have demonstrated the feasibility of using these bubbles as drug carriers in localized delivery. In micro fluidics devices for generation of micro bubbles, the bubbles are formed at interface of liquid gas through a strangulation process. A device that uses these features can produce micro bubbles with small size dispersion in a single step. A T-junction micro fluidic device constructed using 3D prototyping was made for the production of mono dispersed micro bubbles. These micro bubbles use sunflower oil as a lipid layer. Stability studies for micro bubbles with diameters different generated from a liquid phase of the same viscosity were conducted to evaluate whether micro bubbles can be used as drug carriers. The biocompatibility of coating layer, the ability to withstand environmental pressure variations combined with echogenicity, are key factors that they can safely play the role of drug transporters. The normal distribution curve with small dispersion of the diameter of bubbles validates the process of generating micro bubbles with low value of variation coefficient, i.e., 0.381 at 1.90%. The results also showed the feasibility of using sunflower oil as the lipid matrix with stable population of bubbles over 217 minutes for micro bubbles with an average diameter of 313.04 μm and 121 minutes for micro bubbles with an average diameter of 73.74 μm, considering bubbles with air as gaseous phase. The results indicate that the micro fluidic device designed can be used for producing micro bubbles with low variation coefficient using sunflower oil as a coating of micro bubbles. These carriers were stable for periods of time that are long enough for clinical applications even when regular air is used as the gas phase. Improved stability can be achieved when biocompatible gas with lower permeability is used.

Air bubble migration is a random event post embryo transfer.

PubMed

Confino, E; Zhang, J; Risquez, F

2007-06-01

Air bubble location following embryo transfer (ET) is the presumable placement spot of embryos. The purpose of this study was to document endometrial air bubble position and migration following embryo transfer. Multicenter prospective case study. Eighty-eight embryo transfers were performed under abdominal ultrasound guidance in two countries by two authors. A single or double air bubble was loaded with the embryos using a soft, coaxial, end opened catheters. The embryos were slowly injected 10-20 mm from the fundus. Air bubble position was recorded immediately, 30 minutes later and when the patient stood up. Bubble marker location analysis revealed a random distribution without visible gravity effect when the patients stood up. The bubble markers demonstrated splitting, moving in all directions and dispersion. Air bubbles move and split frequently post ET with the patient in the horizontal position, suggestive of active uterine contractions. Bubble migration analysis supports a rather random movement of the bubbles and possibly the embryos. Standing up changed somewhat bubble configuration and distribution in the uterine cavity. Gravity related bubble motion was uncommon, suggesting that horizontal rest post ET may not be necessary. This report challenges the common belief that a very accurate ultrasound guided embryo placement is mandatory. The very random bubble movement observed in this two-center study suggests that a large "window" of embryo placement maybe present.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hu, Shenyang; Setyawan, Wahyu; Joshi, Vineet V.

Xe gas bubble superlattice formation is observed in irradiated uranium–10 wt% molybdenum (U10Mo) fuels. However, the thermodynamic properties of the bubbles (the relationship among bubble size, equilibrium Xe concentration, and bubble pressure) and the mechanisms of bubble growth and superlattice formation are not well known. In this work, molecular dynamics is used to study these properties and mechanisms. The results provide important inputs for quantitative mesoscale models of gas bubble evolution and fuel performance. In the molecular dynamics simulations, the embedded-atom method (EAM) potential of U10Mo-Xe (Smirnova et al. 2013) is employed. Initial gas bubbles with low Xe concentration aremore » generated in a U10Mo single crystal. Then Xe atom atoms are continuously added into the bubbles, and the evolution of pressure and dislocation emission around the bubbles is analyzed. The relationship between pressure, equilibrium Xe concentration, and radius of the bubbles is established. It was found that the gas bubble growth is accompanied by partial dislocation emission, which results in a star-shaped dislocation structure and an anisotropic stress field. The emitted partial dislocations have a Burgers vector along the <111> direction and a slip plane of (11-2). Dislocation loop punch-out was not observed. A tensile stress was found along <110> directions around the bubble, favoring the nucleation and formation of a face-centered cubic bubble superlattice in body-centered cubic U10Mo fuels.« less

Modelling cavitation erosion using fluid–material interaction simulations

PubMed Central

Chahine, Georges L.; Hsiao, Chao-Tsung

2015-01-01

Material deformation and pitting from cavitation bubble collapse is investigated using fluid and material dynamics and their interaction. In the fluid, a novel hybrid approach, which links a boundary element method and a compressible finite difference method, is used to capture non-spherical bubble dynamics and resulting liquid pressures efficiently and accurately. The bubble dynamics is intimately coupled with a finite-element structure model to enable fluid/structure interaction simulations. Bubble collapse loads the material with high impulsive pressures, which result from shock waves and bubble re-entrant jet direct impact on the material surface. The shock wave loading can be from the re-entrant jet impact on the opposite side of the bubble, the fast primary collapse of the bubble, and/or the collapse of the remaining bubble ring. This produces high stress waves, which propagate inside the material, cause deformation, and eventually failure. A permanent deformation or pit is formed when the local equivalent stresses exceed the material yield stress. The pressure loading depends on bubble dynamics parameters such as the size of the bubble at its maximum volume, the bubble standoff distance from the material wall and the pressure driving the bubble collapse. The effects of standoff and material type on the pressure loading and resulting pit formation are highlighted and the effects of bubble interaction on pressure loading and material deformation are preliminarily discussed. PMID:26442140

A study of the accuracy of neutrally buoyant bubbles used as flow tracers in air

NASA Technical Reports Server (NTRS)

Kerho, Michael F.

1993-01-01

Research has been performed to determine the accuracy of neutrally buoyant and near neutrally buoyant bubbles used as flow tracers in air. Theoretical, computational, and experimental results are presented to evaluate the dynamics of bubble trajectories and factors affecting their ability to trace flow-field streamlines. The equation of motion for a single bubble was obtained and evaluated using a computational scheme to determine the factors which affect a bubble's trajectory. A two-dimensional experiment was also conducted to experimentally determine bubble trajectories in the stagnation region of NACA 0012 airfoil at 0 deg angle of attack using a commercially available helium bubble generation system. Physical properties of the experimental bubble trajectories were estimated using the computational scheme. These properties included the density ratio and diameter of the individual bubbles. the helium bubble system was then used to visualize and document the flow field about a 30 deg swept semispan wing with simulated glaze ice. Results were compared to Navier-Stokes calculations and surface oil flow visualization. The theoretical and computational analysis have shown that neutrally buoyant bubbles will trace even the most complex flow patterns. Experimental analysis revealed that the use of bubbles to trace flow patterns should be limited to qualitative measurements unless care is taken to ensure neutral buoyancy. This is due to the difficulty in the production of neutrally buoyant bubbles.

Magnetic skyrmion bubble motion driven by surface acoustic waves

DOE PAGES

Nepal, Rabindra; Güngördü, Utkan; Kovalev, Alexey A.

2018-03-12

Here, we study the dynamical control of a magnetic skyrmion bubble by using counter-propagating surface acoustic waves (SAWs) in a ferromagnet. First, we determine the bubble mass and derive the force due to SAWs acting on a magnetic bubble using Thiele’s method. The force that pushes the bubble is proportional to the strain gradient for the major strain component. We then study the dynamical pinning and motion of magnetic bubbles by SAWs in a nanowire. In a disk geometry, we propose a SAWs-driven skyrmion bubble oscillator with two resonant frequencies.

Magnetic skyrmion bubble motion driven by surface acoustic waves

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nepal, Rabindra; Güngördü, Utkan; Kovalev, Alexey A.

Here, we study the dynamical control of a magnetic skyrmion bubble by using counter-propagating surface acoustic waves (SAWs) in a ferromagnet. First, we determine the bubble mass and derive the force due to SAWs acting on a magnetic bubble using Thiele’s method. The force that pushes the bubble is proportional to the strain gradient for the major strain component. We then study the dynamical pinning and motion of magnetic bubbles by SAWs in a nanowire. In a disk geometry, we propose a SAWs-driven skyrmion bubble oscillator with two resonant frequencies.

Lithotripter shock wave interaction with a bubble near various biomaterials.

PubMed

Ohl, S W; Klaseboer, E; Szeri, A J; Khoo, B C

2016-10-07

Following previous work on the dynamics of an oscillating bubble near a bio-material (Ohl et al 2009 Phys. Med. Biol. 54 6313-36) and the interaction of a bubble with a shockwave (Klaseboer et al 2007 J. Fluid Mech. 593 33-56), the present work concerns the interaction of a gas bubble with a traveling shock wave (such as from a lithotripter) in the vicinity of bio-materials such as fat, skin, muscle, cornea, cartilage, and bone. The bubble is situated in water (to represent a water-like biofluid). The bubble collapses are not spherically symmetric, but tend to feature a high speed jet. A few simulations are performed and compared with available experimental observations from Sankin and Zhong (2006 Phys. Rev. E 74 046304). The collapses of cavitation bubbles (created by laser in the experiment) near an elastic membrane when hit by a lithotripter shock wave are correctly captured by the simulation. This is followed by a more systematic study of the effects involved concerning shockwave bubble biomaterial interactions. If a subsequent rarefaction wave hits the collapsed bubble, it will re-expand to a very large size straining the bio-materials nearby before collapsing once again. It is noted that, for hard bio-material like bone, reflection of the shock wave at the bone-water interface can affect the bubble dynamics. Also the initial size of the bubble has a significant effect. Large bubbles (∼1 mm) will split into smaller bubbles, while small bubbles collapse with a high speed jet in the travel direction of the shock wave. The numerical model offers a computationally efficient way of understanding the complex phenomena involving the interplay of a bubble, a shock wave, and a nearby bio-material.

Lithotripter shock wave interaction with a bubble near various biomaterials

NASA Astrophysics Data System (ADS)

Ohl, S. W.; Klaseboer, E.; Szeri, A. J.; Khoo, B. C.

2016-10-01

Following previous work on the dynamics of an oscillating bubble near a bio-material (Ohl et al 2009 Phys. Med. Biol. 54 6313-36) and the interaction of a bubble with a shockwave (Klaseboer et al 2007 J. Fluid Mech. 593 33-56), the present work concerns the interaction of a gas bubble with a traveling shock wave (such as from a lithotripter) in the vicinity of bio-materials such as fat, skin, muscle, cornea, cartilage, and bone. The bubble is situated in water (to represent a water-like biofluid). The bubble collapses are not spherically symmetric, but tend to feature a high speed jet. A few simulations are performed and compared with available experimental observations from Sankin and Zhong (2006 Phys. Rev. E 74 046304). The collapses of cavitation bubbles (created by laser in the experiment) near an elastic membrane when hit by a lithotripter shock wave are correctly captured by the simulation. This is followed by a more systematic study of the effects involved concerning shockwave bubble biomaterial interactions. If a subsequent rarefaction wave hits the collapsed bubble, it will re-expand to a very large size straining the bio-materials nearby before collapsing once again. It is noted that, for hard bio-material like bone, reflection of the shock wave at the bone—water interface can affect the bubble dynamics. Also the initial size of the bubble has a significant effect. Large bubbles (˜1 mm) will split into smaller bubbles, while small bubbles collapse with a high speed jet in the travel direction of the shock wave. The numerical model offers a computationally efficient way of understanding the complex phenomena involving the interplay of a bubble, a shock wave, and a nearby bio-material.

First Demonstration of a Scintillating Xenon Bubble Chamber for Detecting Dark Matter and Coherent Elastic Neutrino-Nucleus Scattering

NASA Astrophysics Data System (ADS)

Baxter, D.; Chen, C. J.; Crisler, M.; Cwiok, T.; Dahl, C. E.; Grimsted, A.; Gupta, J.; Jin, M.; Puig, R.; Temples, D.; Zhang, J.

2017-06-01

A 30-g xenon bubble chamber, operated at Northwestern University in June and November 2016, has for the first time observed simultaneous bubble nucleation and scintillation by nuclear recoils in a superheated liquid. This chamber is instrumented with a CCD camera for near-IR bubble imaging, a solar-blind photomultiplier tube to detect 175-nm xenon scintillation light, and a piezoelectric acoustic transducer to detect the ultrasonic emission from a growing bubble. The time of nucleation determined from the acoustic signal is used to correlate specific scintillation pulses with bubble-nucleating events. We report on data from this chamber for thermodynamic "Seitz" thresholds from 4.2 to 15.0 keV. The observed single- and multiple-bubble rates when exposed to a Cf 252 neutron source indicate that, for an 8.3-keV thermodynamic threshold, the minimum nuclear recoil energy required to nucleate a bubble is 19 ±6 keV (1 σ uncertainty). This is consistent with the observed scintillation spectrum for bubble-nucleating events. We see no evidence for bubble nucleation by gamma rays at any of the thresholds studied, setting a 90% C.L. upper limit of 6.3 ×10-7 bubbles per gamma interaction at a 4.2-keV thermodynamic threshold. This indicates stronger gamma discrimination than in CF3 I bubble chambers, supporting the hypothesis that scintillation production suppresses bubble nucleation by electron recoils, while nuclear recoils nucleate bubbles as usual. These measurements establish the noble-liquid bubble chamber as a promising new technology for the detection of weakly interacting massive particle dark matter and coherent elastic neutrino-nucleus scattering.

First demonstration of a scintillating xenon bubble chamber for detecting dark matter and coherent elastic neutrino-nucleus scattering

DOE PAGES

Baxter, D.; Chen, C. J.; Crisler, M.; ...

2017-06-08

A 30-g xenon bubble chamber, operated at Northwestern University in June and November 2016, has for the first time observed simultaneous bubble nucleation and scintillation by nuclear recoils in a superheated liquid. This chamber is instrumented with a CCD camera for near-IR bubble imaging, a solar-blind photomultiplier tube to detect 175-nm xenon scintillation light, and a piezoelectric acoustic transducer to detect the ultrasonic emission from a growing bubble. The time of nucleation determined from the acoustic signal is used to correlate specific scintillation pulses with bubble-nucleating events. We report on data from this chamber for thermodynamic "Seitz" thresholds from 4.2 to 15.0 keV. The observed single- and multiple-bubble rates when exposed to amore » $$^{252}$$Cf neutron source indicate that, for an 8.3-keV thermodynamic threshold, the minimum nuclear recoil energy required to nucleate a bubble is $$19\\pm6$$ keV (1$$\\sigma$$ uncertainty). This is consistent with the observed scintillation spectrum for bubble-nucleating events. We see no evidence for bubble nucleation by gamma rays at any of the thresholds studied, setting a 90% C.L. upper limit of $$6.3\\times10^{-7}$$ bubbles per gamma interaction at a 4.2-keV thermodynamic threshold. This indicates stronger gamma discrimination than in CF$$_3$$I bubble chambers, supporting the hypothesis that scintillation production suppresses bubble nucleation by electron recoils while nuclear recoils nucleate bubbles as usual. Finally, these measurements establish the noble-liquid bubble chamber as a promising new technology for the detection of weakly interacting massive particle dark matter and coherent elastic neutrino-nucleus scattering.« less

An evaluation of bubble-CPAP in a neonatal unit in a developing country: effective respiratory support that can be applied by nurses.

PubMed

Koyamaibole, Lanieta; Kado, Joseph; Qovu, Josaia D; Colquhoun, Samantha; Duke, Trevor

2006-08-01

To describe the implementation of bubble-CPAP in a referral hospital in a developing country and to investigate: the feasibility of nurses implementing bubble-CPAP and the impact of bubble-CPAP on need for mechanical ventilation and mortality. Retrospective evaluation of prospectively collected data from two time periods: 18 months before and 18 months after the introduction of bubble-CPAP. The introduction of bubble-CPAP was associated with a 50 per cent reduction in the need for mechanical ventilation; from 113 of 1,106 (10.2 per cent) prior to bubble-CPAP to 70 of 1,382 (5.1%) after introduction of CPAP (chi2, p<0.001). In the 18 months prior to bubble-CPAP there were 79 deaths (case fatality of 7.1 per cent). In the 18 months after bubble-CPAP there were 74 deaths (CF 5.4 per cent), relative risk: 0.75 (0.55-1.02, chi2, p=0.065). Nurses could safely apply bubble-CPAP after 1-2 months of on-the-job training. Equipment for Bubble-CPAP cost 15 per cent of the cost of the cheapest mechanical ventilator. The introduction of bubble-CPAP substantially reduced the need for mechanical ventilation, with no difference in mortality. In models of neonatal care for resource-limited countries, bubble-CPAP may be the first type of ventilatory support that is recommended. Its low cost and safety when administered by nurses makes it ideal for this purpose. Bubble-CPAP has the potential for being available at even lower cost than the current commercially available bubble systems used in this study.

Time-evolving bubbles in two-dimensional stokes flow

NASA Technical Reports Server (NTRS)

Tanveer, Saleh; Vasconcelos, Giovani L.

1994-01-01

A general class of exact solutions is presented for a time evolving bubble in a two-dimensional slow viscous flow in the presence of surface tension. These solutions can describe a bubble in a linear shear flow as well as an expanding or contracting bubble in an otherwise quiescent flow. In the case of expanding bubbles, the solutions have a simple behavior in the sense that for essentially arbitrary initial shapes the bubble will asymptote an expanding circle. Contracting bubbles, on the other hand, can develop narrow structures ('near-cusps') on the interface and may undergo 'break up' before all the bubble-fluid is completely removed. The mathematical structure underlying the existence of these exact solutions is also investigated.

Bubble colloidal AFM probes formed from ultrasonically generated bubbles.

PubMed

Vakarelski, Ivan U; Lee, Judy; Dagastine, Raymond R; Chan, Derek Y C; Stevens, Geoffrey W; Grieser, Franz

2008-02-05

Here we introduce a simple and effective experimental approach to measuring the interaction forces between two small bubbles (approximately 80-140 microm) in aqueous solution during controlled collisions on the scale of micrometers to nanometers. The colloidal probe technique using atomic force microscopy (AFM) was extended to measure interaction forces between a cantilever-attached bubble and surface-attached bubbles of various sizes. By using an ultrasonic source, we generated numerous small bubbles on a mildly hydrophobic surface of a glass slide. A single bubble picked up with a strongly hydrophobized V-shaped cantilever was used as the colloidal probe. Sample force measurements were used to evaluate the pure water bubble cleanliness and the general consistency of the measurements.

Simulations of Bubble Motion in an Oscillating Liquid

NASA Astrophysics Data System (ADS)

Kraynik, A. M.; Romero, L. A.; Torczynski, J. R.

2010-11-01

Finite-element simulations are used to investigate the motion of a gas bubble in a liquid undergoing vertical vibration. The effect of bubble compressibility is studied by comparing "compressible" bubbles that obey the ideal gas law with "incompressible" bubbles that are taken to have constant volume. Compressible bubbles exhibit a net downward motion away from the free surface that does not exist for incompressible bubbles. Net (rectified) velocities are extracted from the simulations and compared with theoretical predictions. The dependence of the rectified velocity on ambient gas pressure, bubble diameter, and bubble depth are in agreement with the theory. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

Camp Minden Fact Sheet July 2015

EPA Pesticide Factsheets

The Louisiana Military Department (LMD) led a Community Meeting on June 30, 2015. The LMD contractor, Explosive Service Intl., and its subcontractor El Dorado Engineering, presented details of Contained Burn System (CBS).

Scheffersomyces parashehatae f.a., sp. nov., Scheffersomyces xylosifermentans f.a., sp. nov., Candida broadrunensis sp. nov. and Candida manassasensis sp. nov., novel yeasts associated with wood-ingesting insects, and their ecological and biofuel implications.

PubMed

Suh, Sung-Oui; Houseknecht, Janice L; Gujjari, Pushpa; Zhou, Jianlong J

2013-11-01

During a survey of yeasts associated with wood-ingesting insects, 69 strains in the Scheffersomyces clade and related taxa were isolated from passalid and tenebrionid beetles and the decayed wood inhabited by them. The majority of these yeasts was found to be capable of fermenting xylose, and was recognized as Scheffersomyces stipitis or its close relative Scheffersomyces illinoinensis, which are known to be associated with wood-decaying beetles and rotten wood. Yeasts in 'Scheffersomyces' ( = Candida) ergatensis and 'Scheffersomyces' ( = Candida) coipomoensis were also frequently isolated. The remaining six strains were identified as representing four novel species in the genera Scheffersomyces and Candida based on multilocus sequence analyses of nuclear rRNA genes and four protein-coding genes, as well as other taxonomic characteristics. Two xylose-fermenting species, Scheffersomyces parashehatae f.a., sp. nov. (type strain ATCC MYA-4653(T) = CBS 12535(T) = EH045(T); MycoBank MB805440) and Scheffersomyces xylosifermentans f.a., sp. nov. (type strain ATCC MYA-4859(T) = CBS 12540(T) = MY10-052(T); MycoBank MB805441), formed a clade with Scheffersomyces shehatae and related Scheffersomyces species. Interestingly, S. xylosifermentans can survive at 40 °C, which is a rare property among xylose-fermenting yeasts. Candida broadrunensis sp. nov. (type strain ATCC MYA-4650(T) = CBS 11838(T) = EH019(T); MycoBank MB805442) is a sister taxon of C. ergatensis, while Candida manassasensis sp. nov. (type strain ATCC MYA-4652(T) = CBS 12534(T) = EH030(T); MycoBank MB805443) is closely related to Candida palmioleophila in the Candida glaebosa clade. The multilocus DNA sequence comparisons in this study suggest that the genus Scheffersomyces needs to be circumscribed to the species near S. stipitis (type species) and S. shehatae that can be characterized by the ability to ferment xylose.

The electron affinity of Al13H cluster: high level ab initio study

NASA Astrophysics Data System (ADS)

Moc, Jerzy

2014-11-01

Al13H clusters have been considered candidates for cluster assembled materials. Here we have carried out benchmark calculations for the Al13H cluster, both neutral and anionic, with the aim of verifying the nature of stationary points on the potential energy surface, studying dynamics of H atom and determining an adiabatic electron affinity. A range of correlated methods applied include second-order perturbation theory (MP2), spin-component-scaled MP2, coupled electron pair (CEPA) and coupled cluster singles and doubles with perturbative triple corrections (CCSD(T)). These methods are used in combination with the correlation consistent basis sets through aug-cc-pVTZ including extrapolation to the complete basis set (CBS) limit. Performance of several different flavours of density functional theory (DFT) such as generalised gradient approximation (GGA), hybrid GGA, meta-GGA and hybrid-meta-GGA is assessed with respect to the ab initio correlated reference data. The harmonic force constant analysis is systematically performed with the MP2 and DFT methods. The MP2 results show that for neutral Al13H only the hollow structure is a potential energy minimum, with the bridged structure being a transition state for the H shift from the hollow site to the adjacent hollow site. The CCSD(T)/aug-cc-pVTZ (CCSD(T)/CBS) estimate of the energy barrier to this H shift is 2.6 (2.9) kcal/mol, implying that the H atom movement over the Al13H cluster surface is facile. By contrast, the DFT force constant analysis results suggest additional terminal and bridged minima structures. For the anion Al13H-, exhibiting 'stiffer' potential energy surface compared to the neutral, the existence of the hollow and terminal isomers is consistent with the earlier photoelectron spectroscopy assignment. The adiabatic electron affinity of Al13H is determined to be 2.00 and 1.95 eV (the latter including the ΔZPE correction) based on the CCSD(T) energies extrapolated to the CBS limit, whereas the respective CCSD(T)/CBS thermodynamic EA values are 2.79 and 2.80 eV.

Height formation of bright points observed by IRIS in Mg II line wings during flux emergence

NASA Astrophysics Data System (ADS)

Grubecka, M.; Schmieder, B.; Berlicki, A.; Heinzel, P.; Dalmasse, K.; Mein, P.

2016-09-01

Context. A flux emergence in the active region AR 111850 was observed on September 24, 2013 with the Interface Region Imaging Spectrograph (IRIS). Many bright points are associated with the new emerging flux and show enhancement brightening in the UV spectra. Aims: The aim of this work is to compute the altitude formation of the compact bright points (CBs) observed in Mg II lines in the context of searching Ellerman bombs (EBs). Methods: IRIS provided two large dense rasters of spectra in Mg II h and k lines, Mg II triplet, C II and Si IV lines covering all the active region and slit jaws in the two bandpasses (1400 Å and 2796 Å) starting at 11:44 UT and 15:39 UT, and lasting 20 min each. Synthetic profiles of Mg II and Hα lines are computed with non-local thermodynamic equlibrium (NLTE) radiative transfer treatment in 1D solar atmosphere model including a hotspot region defined by three parameters: temperature, altitude, and width. Results: Within the two IRIS rasters, 74 CBs are detected in the far wings of the Mg II lines (at +/-1 Å and 3.5 Å). Around 10% of CBs have a signature in Si IV and CII. NLTE models with a hotspot located in the low atmosphere were found to fit a sample of Mg II profiles in CBs. The Hα profiles computed with these Mg II CB models are consistent with typical EB profiles observed from ground based telescopes e.g. THEMIS. A 2D NLTE modelling of fibrils (canopy) demonstrates that the Mg II line centres can be significantly affected but not the peaks and the wings of Mg II lines. Conclusions: We conclude that the bright points observed in Mg II lines can be formed in an extended domain of altitudes in the photosphere and/or the chromosphere (400 to 750 km). Our results are consistent with the theory of heating by Joule dissipation in the atmosphere produced by magnetic field reconnection during flux emergence.

Phase transitions in the common brainstem and related systems investigated by nonstationary time series analysis.

PubMed

Lambertz, M; Vandenhouten, R; Grebe, R; Langhorst, P

2000-01-14

Neuronal activities of the reticular formation (RF) of the lower brainstem and the nucleus tractus solitarii (NTS, first relay station of baroreceptor afferents) were recorded together in the anesthized dog with related parameters of EEG, respiration and cardiovascular system. The RF neurons are part of the common brainstem system (CBS) which participates in regulation and coordination of cardiovascular, respiratory, somatomotor systems, and vigilance. Multiple time series of these physiological subsystems yield useful information about internal dynamic coordination of the organism. Essential problems are nonlinearity and instationarity of the signals, due to the dynamic complexity of the systems. Several time-resolving methods are presented to describe nonlinear dynamic couplings in the time course, particularly during phase transitions. The methods are applied to the recorded signals representing the complex couplings of the physiological subsystems. Phase transitions in these systems are detected by recurrence plots of the instationary signals. The pointwise transinformation and the pointwise conditional coupling divergence are measures of the mutual interaction of the subsystems in the state space. If the signals show marked rhythms, instantaneous frequencies and their shiftings are demonstrated by time frequency distributions, and instantaneous phase differences show couplings of oscillating subsystems. Transient signal components are reconstructed by wavelet packet time selective transient reconstruction. These methods are useful means for analyzing coupling characteristics of the complex physiological system, and detailed analyses of internal dynamic coordination of subsystems become possible. During phase transitions of the functional organization (a) the rhythms of the central neuronal activities and the peripheral systems are altered, (b) changes in the coupling between CBS neurons and cardiovascular signals, respiration and the EEG, and (c) between NTS neurons (influenced by baroreceptor afferents) and CBS neurons occur, and (d) the processing of baroreceptor input at the NTS neurons changes. The results of this complex analysis, which could not be done formerly in this manner, confirm and complete former investigations on the dynamic organization of the CBS with its changing relations to peripheral and other central nervous subsystems.

Determinants of Butyrylcholinesterase Inhibition Among Agricultural Pesticide Handlers in Washington State: An Update

PubMed Central

Krenz, Jennifer E.; Hofmann, Jonathan N.; Smith, Theresa R.; Cunningham, Rad N.; Fenske, Richard A.; Simpson, Christopher D.; Keifer, Matthew

2015-01-01

Objectives: Organophosphate (OP) and N-methyl-carbamate (CB) insecticides are used widely in agriculture to manage insect pests of economic importance. Agricultural workers are more likely to suffer exposure because of the widespread use of OP/CBs in agriculture, and pesticide-related illnesses among handlers may be more severe when compared to other farm workers. The goal of this study was to identify occupational and personal characteristics associated with butyrylcholinesterase (BuChE) inhibition in participants recruited from the Washington State Cholinesterase Monitoring Program from 2006 to 2011. Methods: We conducted a longitudinal study among agricultural pesticide handlers in Washington State during the OP/CB spray season (March–July) over a 6-year period (2006–2011). Linear mixed effects regression models were used to evaluate BuChE inhibition in relation to self-reported occupational and personal characteristics. Results: Relative to pre-season baseline levels, the mean decrease in BuChE activity during the OP/CB spray season over all years of the study period was 3.77% (P < 0.001). Greater BuChE inhibition was observed among handlers who reported using multiple OP/CBs (β = −2.70, P = 0.045), mixed or loaded OP/CBs (β = −3.97, P = 0.002), did not store personal protective equipment (PPE) in a locker at work (β = −3.4, P = 0.014), or did not wear chemical-resistant boots (β = −16.6, P < 0.001). Discussion and Conclusions: The Washington State Cholinesterase Monitoring Program has provided a valuable opportunity to evaluate potential sources of OP/CB exposure among agricultural pesticide handlers. Several previously reported associations were confirmed in the current analysis, which included a larger number of pesticide handlers enrolled over a longer time period. The use of multiple OP/CBs and mixing/loading activities were significant risk factors, and the use of chemical-resistant boots and lockers for PPE storage were protective factors. Our findings point toward logical interventions to reduce exposure such as the implementation of engineering controls for mixing/loading activities, requirements for appropriate footwear, and the regular use of lockers for PPE storage. PMID:25261454

Determinants of butyrylcholinesterase inhibition among agricultural pesticide handlers in Washington State: an update.

PubMed

Krenz, Jennifer E; Hofmann, Jonathan N; Smith, Theresa R; Cunningham, Rad N; Fenske, Richard A; Simpson, Christopher D; Keifer, Matthew

2015-01-01

Organophosphate (OP) and N-methyl-carbamate (CB) insecticides are used widely in agriculture to manage insect pests of economic importance. Agricultural workers are more likely to suffer exposure because of the widespread use of OP/CBs in agriculture, and pesticide-related illnesses among handlers may be more severe when compared to other farm workers. The goal of this study was to identify occupational and personal characteristics associated with butyrylcholinesterase (BuChE) inhibition in participants recruited from the Washington State Cholinesterase Monitoring Program from 2006 to 2011. We conducted a longitudinal study among agricultural pesticide handlers in Washington State during the OP/CB spray season (March-July) over a 6-year period (2006-2011). Linear mixed effects regression models were used to evaluate BuChE inhibition in relation to self-reported occupational and personal characteristics. Relative to pre-season baseline levels, the mean decrease in BuChE activity during the OP/CB spray season over all years of the study period was 3.77% (P < 0.001). Greater BuChE inhibition was observed among handlers who reported using multiple OP/CBs (β = -2.70, P = 0.045), mixed or loaded OP/CBs (β = -3.97, P = 0.002), did not store personal protective equipment (PPE) in a locker at work (β = -3.4, P = 0.014), or did not wear chemical-resistant boots (β = -16.6, P < 0.001). The Washington State Cholinesterase Monitoring Program has provided a valuable opportunity to evaluate potential sources of OP/CB exposure among agricultural pesticide handlers. Several previously reported associations were confirmed in the current analysis, which included a larger number of pesticide handlers enrolled over a longer time period. The use of multiple OP/CBs and mixing/loading activities were significant risk factors, and the use of chemical-resistant boots and lockers for PPE storage were protective factors. Our findings point toward logical interventions to reduce exposure such as the implementation of engineering controls for mixing/loading activities, requirements for appropriate footwear, and the regular use of lockers for PPE storage. © The Author 2014. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

Exhaustive methylation analysis revealed uneven profiles of methylation at IGF2/ICR1/H19 11p15 loci in Russell Silver syndrome.

PubMed

Azzi, Salah; Steunou, Virginie; Tost, Jörg; Rossignol, Sylvie; Thibaud, Nathalie; Das Neves, Cristina; Le Jule, Marilyne; Habib, Walid Abi; Blaise, Annick; Koudou, Yves; Busato, Florence; Le Bouc, Yves; Netchine, Irène

2015-01-01

The structural organisation of the human IGF2/ICR1/H19 11p15 domain is very complex, and the mechanisms underlying its regulation are poorly understood. The Imprinted Center Region 1 (ICR1) contains seven binding sites for the zinc-finger protein CTCF (CBS: CTCF Binding Sites); three additional differentially methylated regions (DMR) are located at the H19 promoter (H19DMR) and two in the IGF2 gene (DMR0 and DMR2), respectively. Loss of imprinting at the IGF2/ICR1/H19 domain results in two growth disorders with opposite phenotypes: Beckwith-Wiedemann syndrome and Russell Silver syndrome (RSS). Despite the IGF2/ICR1/H19 locus being widely studied, the extent of hypomethylation across the domain remains not yet addressed in patients with RSS. We assessed a detailed investigation of the methylation status of the 11p15 ICR1 CBS1-7, IGF2DMR0 and H19DMR (H19 promoter) in a population of controls (n=50) and RSS carrying (n=104) or not (n=65) carrying a hypomethylation at the 11p15 ICR1 region. The methylation indexes (MI) were balanced at all regions in the control population and patients with RSS without any as yet identified molecular anomaly. Interestingly, patients with RSS with ICR1 hypomethylation showed uneven profiles of methylation among the CBSs and DMRs. Furthermore, normal MIs at CBS1 and CBS7 were identified in 9% of patients. The hypomethylation does not spread equally throughout the IGF2/ICR1/H19 locus, and some loci could have normal MI, which may lead to underdiagnosis of patients with RSS with ICR1 hypomethylation. The uneven pattern of methylation suggests that some CBSs may play different roles in the tridimensional chromosomal looping regulation of this locus. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Targeting growth factor supply in keratopathy treatment: comparison between maternal peripheral blood and cord blood as sources for the preparation of topical eye drops

PubMed Central

Versura, Piera; Buzzi, Marina; Giannaccare, Giuseppe; Terzi, Adriana; Fresina, Michela; Velati, Claudio; Campos, Emilio C.

2016-01-01

Background Epitheliotrophic growth factors (GF) can be supplied topically to patients with severe keratopathy through a variety of blood-derived products. We compared GF content in adult peripheral blood serum (PB-S) and cord blood serum (CB-S) as potential sources of GF. To limit inter-individual variability the assessment was performed in maternal-child pairs at the time of delivery. Material and methods The amounts of epidermal GF (EGF), insulin-like GF (IGF), transforming GF-beta (TGF-β), vascular endothelial GF (VEGF) in CB units collected from the umbilical vein and PB from mothers (each group n=30) were estimated by enzyme-linked immunosorbent assays. Obstetric characteristics and haematological data were recorded from the archives of the Emilia Romagna Cord Blood Bank. Statistical evaluations were performed by Wilcoxon’s test and correlations between variables were determined using Spearman’s (ρ) coefficient; p-values <0.05 were considered statistically significant. Results EGF, TGF-β and VEGF levels were significantly higher in CB-S than in PB-S (median 1,254.4 vs 646.0 pg/mL, 51.3 vs 38.4 μg/mL and 686.8 vs 30 pg/mL, respectively; all p<0.0001) whereas IGF content was significantly higher in PB-S than in CB-S (159.9 vs 53.5 pg/mL, respectively; p<0.0001). In CB-S, the CD34+ cell concentration appeared to be related to EGF, IGF and TGF-β levels whereas white blood cell count appeared to be related to EGF and TGF-β levels. VEGF levels showed no relation to the haematological parameters considered. Platelet counts were not related to GF level in either CB or PB. Discussion The GF content in the two blood sources was different, with CB containing larger amounts. Each GF selectively regulates cellular processes involved in corneal healing, so the use of PB or CB should be targeted to supply specific GF on the basis of the type and severity of the keratopathy. PMID:26192781

Upregulation of cystathionine-β-synthetase expression contributes to inflammatory pain in rat temporomandibular joint

PubMed Central

2014-01-01

Background Hydrogen sulfide (H2S), an endogenous gaseotransmitter/modulator, is becoming appreciated that it may be involved in a wide variety of processes including inflammation and nociception. However, the role for H2S in nociceptive processing in trigeminal ganglion (TG) neuron remains unknown. The aim of this study was designed to investigate whether endogenous H2S synthesizing enzyme cystathionine-β-synthetase (CBS) plays a role in inflammatory pain in temporomandibular joint (TMJ). Methods TMJ inflammatory pain was induced by injection of complete Freund’s adjuvant (CFA) into TMJ of adult male rats. Von Frey filaments were used to examine pain behavioral responses in rats following injection of CFA or normal saline (NS). Whole cell patch clamp recordings were employed on acutely isolated TG neurons from rats 2 days after CFA injection. Western blot analysis was carried out to measure protein expression in TGs. Results Injection of CFA into TMJ produced a time dependent hyperalgesia as evidenced by reduced escape threshold in rats responding to VFF stimulation. The reduced escape threshold was partially reversed by injection of O-(Carboxymethyl) hydroxylamine hemihydrochloride (AOAA), an inhibitor for CBS, in a dose-dependent manner. CFA injection led to a marked upregulation of CBS expression when compared with age-matched controls. CFA injection enhanced neuronal excitability as evidenced by depolarization of resting membrane potentials, reduction in rheobase, and an increase in number of action potentials evoked by 2 and 3 times rheobase current stimulation and by a ramp current stimulation of TG neurons innervating the TMJ area. CFA injection also led to a reduction of IK but not IA current density of TG neurons. Application of AOAA in TMJ area reduced the production of H2S in TGs and reversed the enhanced neural hyperexcitability and increased the IK currents of TG neurons. Conclusion These data together with our previous report indicate that endogenous H2S generating enzyme CBS plays an important role in TMJ inflammation, which is likely mediated by inhibition of IK currents, thus identifying a specific molecular mechanism underlying pain and sensitization in TMJ inflammation. PMID:24490955

Applying a framework for assessing the health system challenges to scaling up mHealth in South Africa

PubMed Central

2012-01-01

Background Mobile phone technology has demonstrated the potential to improve health service delivery, but there is little guidance to inform decisions about acquiring and implementing mHealth technology at scale in health systems. Using the case of community-based health services (CBS) in South Africa, we apply a framework to appraise the opportunities and challenges to effective implementation of mHealth at scale in health systems. Methods A qualitative study reviewed the benefits and challenges of mHealth in community-based services in South Africa, through a combination of key informant interviews, site visits to local projects and document reviews. Using a framework adapted from three approaches to reviewing sustainable information and communication technology (ICT), the lessons from local experience and elsewhere formed the basis of a wider consideration of scale up challenges in South Africa. Results Four key system dimensions were identified and assessed: government stewardship and the organisational, technological and financial systems. In South Africa, the opportunities for successful implementation of mHealth include the high prevalence of mobile phones, a supportive policy environment for eHealth, successful use of mHealth for CBS in a number of projects and a well-developed ICT industry. However there are weaknesses in other key health systems areas such as organisational culture and capacity for using health information for management, and the poor availability and use of ICT in primary health care. The technological challenges include the complexity of ensuring interoperability and integration of information systems and securing privacy of information. Finally, there are the challenges of sustainable financing required for large scale use of mobile phone technology in resource limited settings. Conclusion Against a background of a health system with a weak ICT environment and limited implementation capacity, it remains uncertain that the potential benefits of mHealth for CBS would be retained with immediate large-scale implementation. Applying a health systems framework facilitated a systematic appraisal of potential challenges to scaling up mHealth for CBS in South Africa and may be useful for policy and practice decision-making in other low- and middle-income settings. PMID:23126370

Human trophoblast-derived hydrogen sulfide stimulates placental artery endothelial cell angiogenesis.

PubMed

Chen, Dong-Bao; Feng, Lin; Hodges, Jennifer K; Lechuga, Thomas J; Zhang, Honghai

2017-09-01

Endogenous hydrogen sulfide (H2S), mainly synthesized by cystathionine β-synthase (CBS) and cystathionine γ-lyase (CTH), has been implicated in regulating placental angiogenesis; however, the underlying mechanisms are unknown. This study was to test a hypothesis that trophoblasts synthesize H2S to promote placental angiogenesis. Human choriocarcinoma-derived BeWo cells expressed both CBS and CTH proteins, while the first trimester villous trophoblast-originated HTR-8/SVneo cells expressed CTH protein only. The H2S producing ability of BeWo cells was significantly inhibited by either inhibitors of CBS (carboxymethyl hydroxylamine hemihydrochloride, CHH) or CTH (β-cyano-L-alanine, BCA) and that in HTR-8/SVneo cells was inhibited by CHH only. H2S donors stimulated cell proliferation, migration, and tube formation in ovine placental artery endothelial cells (oFPAECs) as effectively as vascular endothelial growth factor. Co-culture with BeWo and HTR-8/SVneo cells stimulated oFPAEC migration, which was inhibited by CHH or BCA in BeWo but CHH only in HTR-8/SVneo cells. Primary human villous trophoblasts (HVT) were more potent than trophoblast cell lines in stimulating oFPAEC migration that was inhibited by CHH and CHH/BCA combination in accordance with its H2S synthesizing activity linked to CBS and CTH expression patterns. H2S donors activated endothelial nitric oxide synthase (NOS3), v-AKT murine thymoma viral oncogene homolog 1 (AKT1), and extracellular signal-activated kinase 1/2 (mitogen-activated protein kinase 3/1, MAPK3/1) in oFPAECs. H2S donor-induced NOS3 activation was blocked by AKT1 but not MAPK3/1 inhibition. In keeping with our previous studies showing a crucial role of AKT1, MAPK3/1, and NOS3/NO in placental angiogenesis, these data show that trophoblast-derived endogenous H2S stimulates placental angiogenesis, involving activation of AKT1, NOS3/NO, and MAPK3/1. © The Authors 2017. Published by Oxford University Press on behalf of Society for the Study of Reproduction. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Vitamin B6 nutritional status and cellular availability of pyridoxal 5'-phosphate govern the function of the transsulfuration pathway's canonical reactions and hydrogen sulfide production via side reactions.

PubMed

Gregory, Jesse F; DeRatt, Barbara N; Rios-Avila, Luisa; Ralat, Maria; Stacpoole, Peter W

2016-07-01

The transsulfuration pathway (TS) acts in sulfur amino acid metabolism by contributing to the regulation of cellular homocysteine, cysteine production, and the generation of H2S for signaling functions. Regulation of TS pathway kinetics involves stimulation of cystathionine β-synthase (CBS) by S-adenosylmethionine (SAM) and oxidants such as H2O2, and by Michaelis-Menten principles whereby substrate concentrations affect reaction rates. Although pyridoxal phosphate (PLP) serves as coenzyme for both CBS and cystathionine γ-lyase (CSE), CSE exhibits much greater loss of activity than CBS during PLP insufficiency. Thus, cellular and plasma cystathionine concentrations increase in vitamin B6 deficiency mainly due to the bottleneck caused by reduced CSE activity. Because of the increase in cystathionine, the canonical production of cysteine (homocysteine → cystathionine → cysteine) is largely maintained even during vitamin B6 deficiency. Typical whole body transsulfuration flux in humans is 3-7 μmol/h per kg body weight. The in vivo kinetics of H2S production via side reactions of CBS and CSE in humans are unknown but they have been reported for cultured HepG2 cells. In these studies, cells exhibit a pronounced reduction in H2S production capacity and rates of lanthionine and homolanthionine synthesis in deficiency. In humans, plasma concentrations of lanthionine and homolanthionine exhibit little or no mean change due to 4-wk vitamin B6 restriction, nor do they respond to pyridoxine supplementation of subjects in chronically low-vitamin B6 status. Wide individual variation in responses of the H2S biomarkers to such perturbations of human vitamin B6 status suggests that the resulting modulation of H2S production may have physiological consequences in a subset of people. Supported by NIH grant DK072398. This paper refers to data from studies registered at clinicaltrials.gov as NCT01128244 and NCT00877812. Copyright © 2016 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

Formation and evolution of bubbly screens in confined oscillating bubbly liquids.

PubMed

Shklyaev, Sergey; Straube, Arthur V

2010-01-01

We consider the dynamics of dilute monodisperse bubbly liquid confined by two plane solid walls and subject to small-amplitude high-frequency oscillations normal to the walls. The initial state corresponds to the uniform distribution of bubbles and motionless liquid. The period of external driving is assumed much smaller than typical relaxation times for a single bubble but larger than the period of volume eigenoscillations. The time-averaged description accounting for the two-way coupling between the liquid and the bubbles is applied. We show that the model predicts accumulation of bubbles in thin sheets parallel to the walls. These singular structures, which are formally characterized by infinitely thin width and infinitely high concentration, are referred to as bubbly screens. The formation of a bubbly screen is described analytically in terms of a self-similar solution, which is in agreement with numerical simulations. We study the evolution of bubbly screens and detect a one-dimensional stationary state, which is shown to be unconditionally unstable.

Formation and evolution of bubbly screens in confined oscillating bubbly liquids

NASA Astrophysics Data System (ADS)

Shklyaev, Sergey; Straube, Arthur V.

2010-01-01

We consider the dynamics of dilute monodisperse bubbly liquid confined by two plane solid walls and subject to small-amplitude high-frequency oscillations normal to the walls. The initial state corresponds to the uniform distribution of bubbles and motionless liquid. The period of external driving is assumed much smaller than typical relaxation times for a single bubble but larger than the period of volume eigenoscillations. The time-averaged description accounting for the two-way coupling between the liquid and the bubbles is applied. We show that the model predicts accumulation of bubbles in thin sheets parallel to the walls. These singular structures, which are formally characterized by infinitely thin width and infinitely high concentration, are referred to as bubbly screens. The formation of a bubbly screen is described analytically in terms of a self-similar solution, which is in agreement with numerical simulations. We study the evolution of bubbly screens and detect a one-dimensional stationary state, which is shown to be unconditionally unstable.

Rational Speculative Bubble Size in Gold, Hang Seng, S&P 500 and Nikkei 225 Index During Year 2008 to 2016

NASA Astrophysics Data System (ADS)

Borhan, Nurharyanti; Halim, Nurfadhlina Abdul; Amir, W. Ahmad Wan Muhammad

2017-09-01

A rational speculative bubble is a surge in asset prices that exceed its intrinsic value. Rational speculative bubbles are among the ascription which may lead to the collapse of an economic system. Rational speculative bubble cannot be created but it comes into existence when assets started to be traded. Financial rational speculative bubble and burst have negative effect on the economy and markets. Financial rational speculative bubbles are difficult to detect. This study aims to shows the size of rational speculative bubble in four markets, which are gold, Hang Seng, S&P500 and Nikkei 225 during year 2008 to 2016. In this study, generalized Johansen-Ledoit-Sornette model are used to find the size of the rational speculative bubble. Bubble detection is important for both sides of macro-economic decision makers and to the trader. Especially for a trading system that requires detailed knowledge about the time and the stage of the bubble burst.

Transport of Gas and Solutes in Permeable Estuarine Sediments

DTIC Science & Technology

2009-01-01

seagrass . 2) To quantify the size range and composition of the gas bubbles in the sediment and the overlying water. 3) To determine the volume change and...from sand containing natural bubbles produced by photosynthesis and control sediment without bubbles. Set up of the pressure tank experiments. The...above the tank will permit bubble growth in the incubated sediment by photosynthesis . RESULTS Fieldwork and bubble production. At CML, ample bubbles

Morphological bubble evolution induced by air diffusion on submerged hydrophobic structures

NASA Astrophysics Data System (ADS)

Lv, Pengyu; Xiang, Yaolei; Xue, Yahui; Lin, Hao; Duan, Huiling

2017-03-01

Bubbles trapped in the cavities always play important roles in the underwater applications of structured hydrophobic surfaces. Air exchange between bubbles and surrounding water has a significant influence on the morphological bubble evolution, which in turn frequently affects the functionalities of the surfaces, such as superhydrophobicity and drag reduction. In this paper, air diffusion induced bubble evolution on submerged hydrophobic micropores under reduced pressures is investigated experimentally and theoretically. The morphological behaviors of collective and single bubbles are observed using confocal microscopy. Four representative evolution phases of bubbles are captured in situ. After depressurization, bubbles will not only grow and coalesce but also shrink and split although the applied pressure remains negative. A diffusion-based model is used to analyze the evolution behavior and the results are consistent with the experimental data. A criterion for bubble growth and shrinkage is also derived along with a phase diagram, revealing that the competition of effective gas partial pressures across the two sides of the diffusion layer dominates the bubble evolution process. Strategies for controlling the bubble evolution behavior are also proposed based on the phase diagram. The current work provides a further understanding of the general behavior of bubble evolution induced by air diffusion and can be employed to better designs of functional microstructured hydrophobic surfaces.

Bubble Proliferation or Dissolution of Cavitation Nuclei in the Beam Path of a Shock-Wave Lithotripter

NASA Astrophysics Data System (ADS)

Frank, Spencer; Lautz, Jaclyn; Sankin, Georgy N.; Szeri, Andrew J.; Zhong, Pei

2015-03-01

It is hypothesized that the decreased treatment efficiency in contemporary shock-wave lithotripters is related to tensile wave attenuation due to cavitation in the prefocal beam path. Utilizing high-speed imaging of the beam path and focal pressure waveform measurements, tensile attenuation is associated with bubble proliferation. By systematically testing different combinations of pulse-repetition frequency and gas concentration, we modulate the bubble-dissolution time to identify which conditions lead to bubble proliferation and show that reducing bubble proliferation in the beam path significantly improves acoustic transmission and stone comminution efficiency in vitro. In addition to experiments, a bubble-proliferation model is developed that takes gas diffusion across the bubble wall and bubble fragmentation into account. By aligning the model with experimental observations, the number of daughter bubbles produced after a single lithotripter bubble collapse is estimated to be in the range of 253 ˜510 . This finding is on the same order of magnitude with previous measurements of an isolated bubble collapse in a lithotripter field by Pishchalnikov, McAteer, and Williams [BJU Int. 102, 1681 (2008), 10.1111/j.1464-410X.2008.07896.x], and this estimate improves the general understanding of lithotripsy bubble dynamics in the beam path.

Dynamics of Two Interactive Bubbles in An Acoustic Field - Part II: Experiments

NASA Astrophysics Data System (ADS)

Ashgriz, Nasser; Barbat, Tiberiu; Liu, Ching-Shi

1996-11-01

The motion of two air bubbles levitated in water, in the presence of a high-frequency acoustic field is experimentally studied. The interaction force between them is named "secondary Bjerknes force" and may be significant in microgravity environments; in our experiments the buoyancy effect is compensated through the action of the "primary Bjerknes forces" - interaction between each bubble oscillation and external sound field. The stationary sound field is produced by a piezoceramic tranducer, in the range of 22-24 kHz. The experiments succesfully demonstrate the existence of three patterns of interaction between bubbles of various sizes: attraction, repulsion and oscillation. Bubbles attraction is quantitatively studied using a high speed video, for "large" bubbles (in the range 0.5-2 mm radius); bubbles repulsion and oscillations are only observed with a regular video, for "small" bubbles (around the resonance size at these frequencies, 0.12 mm). Velocities and accelerations of each bubble are computed from the time history of the motion. The theoretical equations of motion are completed with a drag force formula for single bubbles and solved numerically. Experimental results, for the case of two attracting bubbles, are in good agreement with the numerical model, especially for values of the mutual distance greater than 3 large bubble radii.

Direct observation of individual particle armored bubble interaction, stability, and coalescence dynamics.

PubMed

Tan, Sin-Ying; Ata, Seher; Wanless, Erica J

2013-07-18

The interactions between two individual particle-stabilized bubbles were investigated, in the absence of surfactant, using a combination of coalescence rig and high-speed video camera. This combination allows the visualization of bubble coalescence dynamics which provide information on bubble stability. Experimental data suggested that bubble stability is enhanced by both the adsorption of particles at the interface as indicated by the long induction time and the increase in damping coefficient at high surface coverage. The interaction between an armored bubble and a bare bubble (asymmetric interaction) can be destabilized through the addition of a small amount of salt, which suggested that electrostatic interactions play a significant role in bubble stability. Interestingly, the DLVO theory cannot be used to describe the bubble stability in the case of a symmetric interaction as coalescence was inhibited at 0.1 M KCl in both the absence and presence of particles at the interfaces. Furthermore, bubbles can also be destabilized by increasing the particle hydrophobicity. This behavior is due to thinner liquid films between bubbles and an increase in film drainage rate. The fraction of particles detached from the bubble surface after film rupture was found to be very similar within the range of solution ionic strength, surface coverage, and particle hydrophobicity studied. This lack of dependence implies that the kinetic energy generated by the coalescing bubbles is larger than the attachment energy of the particles and dominates the detachment process. This study illuminates the stability behavior of individual particle-stabilized bubbles and has potential impact on processes which involve their interaction.

Perturbation of a radially oscillating single-bubble by a micron-sized object.

PubMed

Montes-Quiroz, W; Baillon, F; Louisnard, O; Boyer, B; Espitalier, F

2017-03-01

A single bubble oscillating in a levitation cell is acoustically monitored by a piezo-ceramics microphone glued on the cell external wall. The correlation of the filtered signal recorded over distant cycles on one hand, and its harmonic content on the other hand, are shown to carry rich information on the bubble stability and existence. For example, the harmonic content of the signal is shown to increase drastically once air is fully dissociated in the bubble, and the resulting pure argon bubble enters into the upper branch of the sonoluminescence regime. As a consequence, the bubble disappearance can be unambiguously detected by a net drop in the harmonic content. On the other hand, we perturb a stable sonoluminescing bubble by approaching a micron-sized fiber. The bubble remains unperturbed until the fiber tip is approached within a critical distance, below which the bubble becomes unstable and disappears. This distance can be easily measured by image treatment, and is shown to scale roughly with 3-4 times the bubble maximal radius. The bubble disappearance is well detected by the drop of the microphone harmonic content, but several thousands of periods after the bubble actually disappeared. The delay is attributed to the slow extinction of higher modes of the levitation cell, excited by the bubble oscillation. The acoustic detection method should however allow the early detection and imaging of non-predictable perturbations of the bubble by foreign micron-sized objects, such as crystals or droplets. Copyright © 2016 Elsevier B.V. All rights reserved.

Numerical Analysis of the Influence of Low Frequency Vibration on Bubble Growth

PubMed Central

Han, D.; Kedzierski, Mark A.

2017-01-01

Numerical simulation of bubble growth during pool boiling under the influence of low frequency vibration was performed to understand the influence of common vibrations such as those induced by wind, highway transportation, and nearby mechanical devices on the performance of thermal systems that rely on boiling. The simulations were done for saturated R123 boiling at 277.6 K with a 15 K wall superheat. The numerical volume-of-fluid method (fixed grid) was used to define the liquid-vapor interface. The basic bubble growth characteristics including the bubble departure diameter and the bubble departure time were determined as a function of the bubble contact angle (20°–80°), the vibration displacement (10 µm–50 µm), the vibration frequency (5 Hz–25 Hz), and the initial vibration direction (positive or negative). The bubble parameters were shown to be strongly dependent on the bubble contact angle at the surface. For example, both the bubble departure diameter and the bubble departure time increased with the contact angle. At the same vibration frequency and the initial vibration direction, the bubble departure diameter and the bubble departure time both decreased with increasing vibration displacement. In addition, the vibration frequency had a greater effect on the bubble growth characteristics than did the vibration displacement. The vibration frequency effect was strongly influenced by the initial vibration direction. The pressure contour, the volume fraction of vapor phase, the temperature profile, and the velocity vector were investigated to understand these dynamic bubble behaviors. The limitation of the computational fluid dynamics approach was also described. PMID:28747812

Further experimentation on bubble generation during transformer overload

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oommen, T.V.

1992-03-01

This report covers additional work done during 1990 and 1991 on gas bubble generation under overload conditions. To improve visual bubble detection, a single disc coil was used. To further improve detection, a corona device was also used which signaled the onset of corona activity in the early stages of bubble formation. A total of fourteen model tests were conducted, half of which used the Inertaire system, and the remaining, a conservator (COPS). Moisture content of paper in the coil varied from 1.0% to 8.0%; gas (nitrogen) content varied from 1.0% to 8.8%. The results confirmed earlier observations that themore » mathematical bubble prediction model was not valid for high gas content model with relatively low moisture levels in the coil. An empirical relationship was formulated to accurately predict bubble evolution temperatures from known moisture and gas content values. For low moisture content models (below 2%), the simple Piper relationship was sufficient to predict bubble evolution temperatures, regardless of gas content. Moisture in the coil appears to be the key factor in bubble generation. Gas blanketed (Inertaire) systems do not appear to be prone to premature bubble generation from overloads as previously thought. The new bubble prediction model reveals that for a coil with 2% moisture, the bubble evolution temperature would be about 140{degrees}C. Since old transformers in service may have as much as 2% moisture in paper, the 140{degrees}C bubble evolution temperature may be taken as the lower limit of bubble evolution temperature under overload conditions for operating transformers. Drier insulation would raise the bubble evolution temperature.« less

Removal of residual nuclei following a cavitation event using low-amplitude ultrasound.

PubMed

Duryea, Alexander P; Cain, Charles A; Tamaddoni, Hedieh A; Roberts, William W; Hall, Timothy L

2014-10-01

Microscopic residual bubble nuclei can persist on the order of 1 s following a cavitation event. These bubbles can limit the efficacy of ultrasound therapies such as shock wave lithotripsy and histotripsy, because they attenuate pulses that arrive subsequent to their formation and seed repetitive cavitation activity at a discrete set of sites (cavitation memory). Here, we explore a strategy for the removal of these residual bubbles following a cavitation event, using low-amplitude ultrasound pulses to stimulate bubble coalescence. All experiments were conducted in degassed water and monitored using high-speed photography. In each case, a 2-MHz histotripsy transducer was used to initiate cavitation activity (a cavitational bubble cloud), the collapse of which generated a population of residual bubble nuclei. This residual nuclei population was then sonicated using a 1 ms pulse from a separate 500-kHz transducer, which we term the bubble removal pulse. Bubble removal pulse amplitudes ranging from 0 to 1.7 MPa were tested, and the backlit area of shadow from bubbles remaining in the field following bubble removal was calculated to quantify efficacy. It was found that an ideal amplitude range exists (roughly 180 to 570 kPa) in which bubble removal pulses stimulate the aggregation and subsequent coalescence of residual bubble nuclei, effectively removing them from the field. Further optimization of bubble removal pulse sequences stands to provide an adjunct to cavitation-based ultrasound therapies such as shock wave lithotripsy and histotripsy, mitigating the effects of residual bubble nuclei that currently limit their efficacy.

Quantification of Methane Gas Flux and Bubble Fate on the Eastern Siberian Arctic Shelf Utilizing Calibrated Split-beam Echosounder Data.

NASA Astrophysics Data System (ADS)

Weidner, E. F.; Mayer, L. A.; Weber, T. C.; Jerram, K.; Jakobsson, M.; Chernykh, D.; Ananiev, R.; Mohammad, R.; Semiletov, I. P.

2016-12-01

On the Eastern Siberian Arctic Shelf (ESAS) subsea permafrost, shallow gas hydrates, and trapped free gas hold an estimated 1400 Gt of methane. Recent observations of methane bubble plumes and high concentrations of dissolved methane in the water column indicate methane release via ebullition. Methane gas released from the shallow ESAS (<50 m average depth) has high potential to be transported to the atmosphere. To directly and quantitatively address the magnitude of methane flux and the fate of rising bubbles in the ESAS, methane seeps were mapped with a broadband split-beam echosounder as part of the Swedish-Russian-US Arctic Ocean Investigation of Climate-Cryosphere-Carbon Interactions program (SWERUS-C3). Acoustic measurements were made over a broad range of frequencies (16 to 29 kHz). The broad bandwidth provided excellent discrimination of individual targets in the water column, allowing for the identification of single bubbles. Absolute bubble target strength values were determined by compensating apparent target strength measurements for beam pattern effects via standard calibration techniques. The bubble size distribution of seeps with individual bubble signatures was determined by exploiting bubble target strength models over the broad range of frequencies. For denser seeps, with potential higher methane flux, bubble size distribution was determined via extrapolation from seeps in similar geomorphological settings. By coupling bubble size distributions with rise velocity measurements, which are made possible by split-beam target tracking, methane gas flux can be estimated. Of the 56 identified seeps in the SWERUS data set, individual bubbles scatterers were identified in more than half (31) of the seeps. Preliminary bubble size distribution results indicate bubble radii range from 0.75 to 3.0 mm, with relatively constant bubble size distribution throughout the water column. Initial rise velocity observations indicate bubble rise velocity increases with decreasing depth, seemingly independent of bubble radius.

Effect of oxygen breathing on micro oxygen bubbles in nitrogen-depleted rat adipose tissue at sea level and 25 kPa altitude exposures.

PubMed

Randsoe, Thomas; Hyldegaard, Ole

2012-08-01

The standard treatment of altitude decompression sickness (aDCS) caused by nitrogen bubble formation is oxygen breathing and recompression. However, micro air bubbles (containing 79% nitrogen), injected into adipose tissue, grow and stabilize at 25 kPa regardless of continued oxygen breathing and the tissue nitrogen pressure. To quantify the contribution of oxygen to bubble growth at altitude, micro oxygen bubbles (containing 0% nitrogen) were injected into the adipose tissue of rats depleted from nitrogen by means of preoxygenation (fraction of inspired oxygen = 1.0; 100%) and the bubbles studied at 101.3 kPa (sea level) or at 25 kPa altitude exposures during continued oxygen breathing. In keeping with previous observations and bubble kinetic models, we hypothesize that oxygen breathing may contribute to oxygen bubble growth at altitude. Anesthetized rats were exposed to 3 h of oxygen prebreathing at 101.3 kPa (sea level). Micro oxygen bubbles of 500-800 nl were then injected into the exposed abdominal adipose tissue. The oxygen bubbles were studied for up to 3.5 h during continued oxygen breathing at either 101.3 or 25 kPa ambient pressures. At 101.3 kPa, all bubbles shrank consistently until they disappeared from view at a net disappearance rate (0.02 mm(2) × min(-1)) significantly faster than for similar bubbles at 25 kPa altitude (0.01 mm(2) × min(-1)). At 25 kPa, most bubbles initially grew for 2-40 min, after which they shrank and disappeared. Four bubbles did not disappear while at 25 kPa. The results support bubble kinetic models based on Fick's first law of diffusion, Boyles law, and the oxygen window effect, predicting that oxygen contributes more to bubble volume and growth during hypobaric conditions. As the effect of oxygen increases, the lower the ambient pressure. The results indicate that recompression is instrumental in the treatment of aDCS.

Expansion of a compressible gas bubble in Stokes flow

NASA Astrophysics Data System (ADS)

Pozrikidis, C.

2001-09-01

The flow-induced deformation of an inviscid bubble occupied by a compressible gas and suspended in an ambient viscous liquid is considered at low Reynolds numbers with particular reference to the pressure developing inside the bubble. Ambient fluid motion alters the bubble pressure with respect to that established in the quiescent state, and requires the bubble to expand or contract according to an assumed equation of state. When changes in the bubble volume are prohibited by a global constraint on the total volume of the flow, the ambient pressure is modified while the bubble pressure remains constant during the deformation. A numerical method is developed for evaluating the pressure inside a two-dimensional bubble in an ambient Stokes flow on the basis of the normal component of the interfacial force balance involving the capillary pressure, the normal viscous stress, and the pressure at the free surface on the side of the liquid; the last is computed by evaluating a strongly singular integral. Dynamical simulations of bubble deformation are performed using the boundary integral method properly implemented to remove the multiplicity of solutions due to the a priori unknown rate of expansion, and three particular problems are discussed in detail: the shrinkage of a bubble at a specified rate, the deformation of a bubble subject to simple shear flow, and the deformation of a bubble subject to a purely elongational flow. In the case of shrinkage, it is found that the surface tension plays a critical role in determining the behaviour of the bubble pressure near the critical time when the bubble disappears. In the case of shear or elongational flow, it is found that the bubble contracts during an initial period of deformation from the circular shape, and then it expands to obtain a stationary shape whose area is higher than that assumed in the quiescent state. Expansion may destabilize the bubble by raising the capillary number above the critical threshold under which stationary shapes can be found.

The alveolar surface network: a new anatomy and its physiological significance.

PubMed

Scarpelli, E M

1998-08-01

It is generally held that the terminal lung unit (TLU) is an agglomeration of alveoli that opens into the branching air spaces of respiratory bronchioles, alveolar ducts, and alveolar sacs and that these structures are covered by a continuous thin liquid layer bearing a monomolecular film of surfactants at the open gas-liquid interface. The inherent structural and functional instability given TLUs by a broad liquid surface layer of this nature has been mitigated by the discovery that the TLU surface is in fact an agglomeration of bubbles, a foam (the alveolar surface network) that fills the TLU space and forms ultrathin foam films that 1) impart infrastructural stability to sustain aeration, 2) modulate circulation of surface liquid, both in series and in parallel, throughout the TLU and between TLUs and the liquid surface of conducting airways, 3) modulate surface liquid volume and exchange with interstitial liquid, and 4) sustain gas transfer between conducting airways and pulmonary capillaries throughout the respiratory cycle. The experimental evidence, from discovery to the present, is addressed in this report. Lungs were examined in thorax by stereomicroscopy immediately from the in vivo state at volumes ranging from functional residual capacity to maximal volume (Vmax). Lungs were then excised; bubble topography of all anterior and anterolateral surfaces was reaffirmed and also confirmed for all posterior and posterolateral surfaces. The following additional criteria verify the ubiquitous presence of normal intraalveolar bubbles. 1) Bubbles are absent in conducting airways. 2) Bubbles are stable and stationary in TLUs but can be moved individually by gentle microprobe pressure. 3) Adjoining bubbles move into the external medium through subpleural microincisions; there is no free gas, and vacated spaces are rendered airless. Adjacent bubbles may shift position in situ, while more distal bubbles remain stationary. 4) The position and movement of "large" bubbles identifies them as intraductal bubbles. 5) Transection of the lung reveals analogous bubble occurrence and history in central lung regions. 6) Bubbles become fixed in place and change shape when the lung is dried in air; the original shape and movement are restored when the lung is rewet. 7) All exteriorized bubbles are stable with lamellar (film) surface tension near zero. 8) Intact lungs prepared and processed by the new double-embedding technique reveal the intact TLU bubbles and bubble films. Lungs were also monitored directly by stereomicroscopy to establish their presence, transformations, and apparent function from birth through adulthood, as summarized in the following section. Intraalveolar bubbles and bubble films (the unit structures of the alveolar surface network) have been found in all mammalian species examined to date, including lambs, kids, and rabbit pups and adult mice, rats, rabbits, cats, and pigs. Rabbits were used for the definitive studies. 1) A unit bubble occupies each alveolus and branching airway of the TLU; unit bubbles in clusters correspond with alveolar clusters. 2) The appositions of unit bubble lamellae (films) form a network of liquid channels within the TLUs. The appositions are bubble to bubble (near alveolar entrances, at pores of Kohn, and between ductal bubbles), bubble to epithelial cell surface, and bubble to surface liquid of conducting airways. They rapidly form stable Newtonian black foam films (approximately 7 nm thick) under hydrodynamic conditions expected in vivo. 3) Lamellae of the foam films and bubbles tend to exclude bulk liquid and thus maintain near-zero surface tension. At the same time, the foam film formations--abetted by the constant but small retractive force of tissue recoil--stabilize unit bubble position within the network. 4) Unit bubble mobility in response to applied force increases as liquid accumulates within the network (e.g. (ABSTRACT TRUNCATED)

Eternal inflation, bubble collisions, and the persistence of memory

NASA Astrophysics Data System (ADS)

Garriga, Jaume; Guth, Alan H.; Vilenkin, Alexander

2007-12-01

A “bubble universe” nucleating in an eternally inflating false vacuum will experience, in the course of its expansion, collisions with an infinite number of other bubbles. In an idealized model, we calculate the rate of collisions around an observer inside a given reference bubble. We show that the collision rate violates both the homogeneity and the isotropy of the bubble universe. Each bubble has a center which can be related to “the beginning of inflation” in the parent false vacuum, and any observer not at the center will see an anisotropic bubble collision rate that peaks in the outward direction. Surprisingly, this memory of the onset of inflation persists no matter how much time elapses before the nucleation of the reference bubble.

Walks of bubbles on a hot wire in a liquid bath

NASA Astrophysics Data System (ADS)

Duchesne, A.; Caps, H.

2017-05-01

When a horizontal resistive wire is heated up to the boiling point in a subcooled liquid bath, some vapor bubbles nucleate on its surface. The traditional nucleate boiling theory predicts that bubbles generated from active nucleate sites grow up and depart from the heating surface due to buoyancy and inertia. However, we observed here a different behavior: the bubbles slide along the heated wire. In this situation, unexpected regimes are observed; from the simple sliding motion to bubble clustering. We noticed that bubbles could rapidly change their moving direction and may also interact. Finally, we propose an interpretation for both the attraction between the bubbles and the wire and for the motion of the bubbles on the wire in terms of Marangoni effects.

A boundary element model of the transport of a semi-infinite bubble through a microvessel bifurcation

NASA Astrophysics Data System (ADS)

Calderon, Andres J.; Eshpuniyani, Brijesh; Fowlkes, J. Brian; Bull, Joseph L.

2010-06-01

Motivated by a developmental gas embolotherapy technique for selective occlusion of blood flow to tumors, we examined the transport of a pressure-driven semi-infinite bubble through a liquid-filled bifurcating channel. Homogeneity of bubble splitting as the bubble passes through a vessel bifurcation affects the degree to which the vascular network near the tumor can be uniformly occluded. The homogeneity of bubble splitting was found to increase with bubble driving pressure and to decrease with increased bifurcation angle. Viscous losses at the bifurcation were observed to affect the bubble speed significantly. The potential for oscillating bubble interfaces to induce flow recirculation and impart high stresses on the vessel endothelium was also observed.

Effect of an entrained air bubble on the acoustics of an ink channel.

PubMed

Jeurissen, Roger; de Jong, Jos; Reinten, Hans; van den Berg, Marc; Wijshoff, Herman; Versluis, Michel; Lohse, Detlef

2008-05-01

Piezo-driven inkjet systems are very sensitive to air entrapment. The entrapped air bubbles grow by rectified diffusion in the ink channel and finally result in nozzle failure. Experimental results on the dynamics of fully grown air bubbles are presented. It is found that the bubble counteracts the pressure buildup necessary for the droplet formation. The channel acoustics and the air bubble dynamics are modeled. For good agreement with the experimental data it is crucial to include the confined geometry into the model: The air bubble acts back on the acoustic field in the channel and thus on its own dynamics. This two-way coupling limits further bubble growth and thus determines the saturation size of the bubble.

Cartilage formation in the CELLS 'double bubble' hardware

NASA Technical Reports Server (NTRS)

Duke, P. J.; Arizpe, Jorge; Montufar-Solis, Dina

1991-01-01

The CELLS experiment scheduled to be flown on the first International Microgravity Laboratory is designed to study the effect of microgravity on the cartilage formation, by measuring parameters of growth in a differentiating cartilage cell culture. This paper investigates the conditions for this experiment by studying cartilage differentiation in the 'bubble exchange' hardware with the 'double bubble' design in which the bubbles are joined by a flange which also overlays the gasket. Four types of double bubbles (or double gas permeable membranes) were tested: injection-molded bubbles 0.01- and 0.005-in. thick, and compression molded bubbles 0.015- and 0.01-in. thick. It was found that double bubble membranes of 0.005- and 0.010-in. thickness supported cartilage differentiation, while the 0.015-in. bubbles did not. It was also found that nodule count, used in this study as a parameter, is not the best measure of the amount of cartilage differentiation.

Time-resolved imaging of electrical discharge development in underwater bubbles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tu, Yalong; Xia, Hualei; Yang, Yong, E-mail: yangyong@hust.edu.cn, E-mail: luxinpei@hust.edu.cn

2016-01-15

The formation and development of plasma in single air bubbles submerged in water were investigated. The difference in the discharge dynamics and the after-effects on the bubble were investigated using a 900 000 frame per second high-speed charge-coupled device camera. It was observed that depending on the position of the electrodes, the breakdown could be categorized into two modes: (1) direct discharge mode, where the high voltage and ground electrodes were in contact with the bubble, and the streamer would follow the shortest path and propagate along the axis of the bubble and (2) dielectric barrier mode, where the groundmore » electrode was not in touch with the bubble surface, and the streamer would form along the inner surface of the bubble. The oscillation of the bubble and the development of instabilities on the bubble surface were also discussed.« less

Unorthodox bubbles when boiling in cold water.

PubMed

Parker, Scott; Granick, Steve

2014-01-01

High-speed movies are taken when bubbles grow at gold surfaces heated spotwise with a near-infrared laser beam heating water below the boiling point (60-70 °C) with heating powers spanning the range from very low to so high that water fails to rewet the surface after bubbles detach. Roughly half the bubbles are conventional: They grow symmetrically through evaporation until buoyancy lifts them away. Others have unorthodox shapes and appear to contribute disproportionately to heat transfer efficiency: mushroom cloud shapes, violently explosive bubbles, and cavitation events, probably stimulated by a combination of superheating, convection, turbulence, and surface dewetting during the initial bubble growth. Moreover, bubbles often follow one another in complex sequences, often beginning with an unorthodox bubble that stirs the water, followed by several conventional bubbles. This large dataset is analyzed and discussed with emphasis on how explosive phenomena such as cavitation induce discrepancies from classical expectations about boiling.

Bubble memory module for spacecraft application

NASA Technical Reports Server (NTRS)

Hayes, P. J.; Looney, K. T.; Nichols, C. D.

1985-01-01

Bubble domain technology offers an all-solid-state alternative for data storage in onboard data systems. A versatile modular bubble memory concept was developed. The key module is the bubble memory module which contains all of the storage devices and circuitry for accessing these devices. This report documents the bubble memory module design and preliminary hardware designs aimed at memory module functional demonstration with available commercial bubble devices. The system architecture provides simultaneous operation of bubble devices to attain high data rates. Banks of bubble devices are accessed by a given bubble controller to minimize controller parts. A power strobing technique is discussed which could minimize the average system power dissipation. A fast initialization method using EEPROM (electrically erasable, programmable read-only memory) devices promotes fast access. Noise and crosstalk problems and implementations to minimize these are discussed. Flight memory systems which incorporate the concepts and techniques of this work could now be developed for applications.

Electric field observations of equatorial bubbles

NASA Technical Reports Server (NTRS)

Aggson, T. L.; Maynard, N. C.; Hanson, W. B.; Saba, Jack L.

1992-01-01

Results from the double floating probe experiment performed on the San Marco D satellite are presented, with emphasis on the observation of large incremental changes in the convective electric field vector at the boundary of equatorial plasma bubbles. Attention is given to isolated bubble structures in the upper ionospheric F regions; these observed bubble encounters are divided into two types - type I (live bubbles) and type II (dead bubbles). Type I bubbles show varying degrees of plasma depletion and large upward velocities range up to 1000 km/s. The geometry of these bubbles is such that the spacecraft orbit may cut them where they are tilting either eastward or (more often) westward. Type II bubbles exhibit plasma density depletion but no appreciable upward convection. Both types of events are usually surrounded by a halo of plasma turbulence, which can extend considerably beyond the region of plasma depletion.

Feasibility of self-structured current accessed bubble devices in spacecraft recording systems

NASA Technical Reports Server (NTRS)

Nelson, G. L.; Krahn, D. R.; Dean, R. H.; Paul, M. C.; Lo, D. S.; Amundsen, D. L.; Stein, G. A.

1985-01-01

The self-structured, current aperture approach to magnetic bubble memory is described. Key results include: (1) demonstration that self-structured bubbles (a lattice of strongly interacting bubbles) will slip by one another in a storage loop at spacings of 2.5 bubble diameters, (2) the ability of self-structured bubbles to move past international fabrication defects (missing apertures) in the propagation conductors (defeat tolerance), and (3) moving bubbles at mobility limited speeds. Milled barriers in the epitaxial garnet are discussed for containment of the bubble lattice. Experimental work on input/output tracks, storage loops, gates, generators, and magneto-resistive detectors for a prototype device are discussed. Potential final device architectures are described with modeling of power consumption, data rates, and access times. Appendices compare the self-structured bubble memory from the device and system perspectives with other non-volatile memory technologies.

Bubble behavior characteristics based on virtual binocular stereo vision

NASA Astrophysics Data System (ADS)

Xue, Ting; Xu, Ling-shuang; Zhang, Shang-zhen

2018-01-01

The three-dimensional (3D) behavior characteristics of bubble rising in gas-liquid two-phase flow are of great importance to study bubbly flow mechanism and guide engineering practice. Based on the dual-perspective imaging of virtual binocular stereo vision, the 3D behavior characteristics of bubbles in gas-liquid two-phase flow are studied in detail, which effectively increases the projection information of bubbles to acquire more accurate behavior features. In this paper, the variations of bubble equivalent diameter, volume, velocity and trajectory in the rising process are estimated, and the factors affecting bubble behavior characteristics are analyzed. It is shown that the method is real-time and valid, the equivalent diameter of the rising bubble in the stagnant water is periodically changed, and the crests and troughs in the equivalent diameter curve appear alternately. The bubble behavior characteristics as well as the spiral amplitude are affected by the orifice diameter and the gas volume flow.

Numerical simulation of cavitation bubble dynamics induced by ultrasound waves in a high frequency reactor.

PubMed

Servant, G; Caltagirone, J P; Gérard, A; Laborde, J L; Hita, A

2000-10-01

The use of high frequency ultrasound in chemical systems is of major interest to optimize chemical procedures. Characterization of an open air 477 kHz ultrasound reactor shows that, because of the collapse of transient cavitation bubbles and pulsation of stable cavitation bubbles, chemical reactions are enhanced. Numerical modelling is undertaken to determine the spatio-temporal evolution of cavitation bubbles. The calculus of the emergence of cavitation bubbles due to the acoustic driving (by taking into account interactions between the sound field and bubbles' distribution) gives a cartography of bubbles' emergence within the reactor. Computation of their motion induced by the pressure gradients occurring in the reactor show that they migrate to the pressure nodes. Computed bubbles levitation sites gives a cartography of the chemical activity of ultrasound. Modelling of stable cavitation bubbles' motion induced by the motion of the liquid gives some insight on degassing phenomena.

The collapse of a cavitation bubble in a corner

NASA Astrophysics Data System (ADS)

Peters, Ivo; Tagawa, Yoshiyuki

2017-11-01

The collapse of cavitation bubbles is influenced by the surrounding geometry. A classic example is the collapse of a bubble near a solid wall, where a fast jet is created towards the wall. The addition of a second wall creates a non-axisymmetric flow field, which influences the displacement and jet formation during the collapse of a bubble. In this experimental study we generate mm-sized vapor bubbles using a focused pulsed laser, giving us full control over the position of the bubble. The corner geometry is formed by two glass slides. High-speed imaging reveals the directional motion of the bubble during the collapse. We find that the bubble displacement cannot be fully described by a simple superposition of the bubble dynamics of the two walls individually. Comparison of our experimental results to a model based on potential flow shows a good agreement for the direction of displacement.

Prediction of Cavitation Depth in an Al-Cu Alloy Melt with Bubble Characteristics Based on Synchrotron X-ray Radiography

NASA Astrophysics Data System (ADS)

Huang, Haijun; Shu, Da; Fu, Yanan; Zhu, Guoliang; Wang, Donghong; Dong, Anping; Sun, Baode

2018-06-01

The size of cavitation region is a key parameter to estimate the metallurgical effect of ultrasonic melt treatment (UST) on preferential structure refinement. We present a simple numerical model to predict the characteristic length of the cavitation region, termed cavitation depth, in a metal melt. The model is based on wave propagation with acoustic attenuation caused by cavitation bubbles which are dependent on bubble characteristics and ultrasonic intensity. In situ synchrotron X-ray imaging of cavitation bubbles has been made to quantitatively measure the size of cavitation region and volume fraction and size distribution of cavitation bubbles in an Al-Cu melt. The results show that cavitation bubbles maintain a log-normal size distribution, and the volume fraction of cavitation bubbles obeys a tanh function with the applied ultrasonic intensity. Using the experimental values of bubble characteristics as input, the predicted cavitation depth agrees well with observations except for a slight deviation at higher acoustic intensities. Further analysis shows that the increase of bubble volume and bubble size both leads to higher attenuation by cavitation bubbles, and hence, smaller cavitation depth. The current model offers a guideline to implement UST, especially for structural refinement.

A bubble detection system for propellant filling pipeline

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wen, Wen; Zong, Guanghua; Bi, Shusheng

2014-06-15

This paper proposes a bubble detection system based on the ultrasound transmission method, mainly for probing high-speed bubbles in the satellite propellant filling pipeline. First, three common ultrasonic detection methods are compared and the ultrasound transmission method is used in this paper. Then, the ultrasound beam in a vertical pipe is investigated, suggesting that the width of the beam used for detection is usually smaller than the internal diameter of the pipe, which means that when bubbles move close to the pipe wall, they may escape from being detected. A special device is designed to solve this problem. It canmore » generate the spiral flow to force all the bubbles to ascend along the central line of the pipe. In the end, experiments are implemented to evaluate the performance of this system. Bubbles of five different sizes are generated and detected. Experiment results show that the sizes and quantity of bubbles can be estimated by this system. Also, the bubbles of different radii can be distinguished from each other. The numerical relationship between the ultrasound attenuation and the bubble radius is acquired and it can be utilized for estimating the unknown bubble size and measuring the total bubble volume.« less

Single-bubble and multibubble cavitation in water triggered by laser-driven focusing shock waves

NASA Astrophysics Data System (ADS)

Veysset, D.; Gutiérrez-Hernández, U.; Dresselhaus-Cooper, L.; De Colle, F.; Kooi, S.; Nelson, K. A.; Quinto-Su, P. A.; Pezeril, T.

2018-05-01

In this study a single laser pulse spatially shaped into a ring is focused into a thin water layer, creating an annular cavitation bubble and cylindrical shock waves: an outer shock that diverges away from the excitation laser ring and an inner shock that focuses towards the center. A few nanoseconds after the converging shock reaches the focus and diverges away from the center, a single bubble nucleates at the center. The inner diverging shock then reaches the surface of the annular laser-induced bubble and reflects at the boundary, initiating nucleation of a tertiary bubble cloud. In the present experiments, we have performed time-resolved imaging of shock propagation and bubble wall motion. Our experimental observations of single-bubble cavitation and collapse and appearance of ring-shaped bubble clouds are consistent with our numerical simulations that solve a one-dimensional Euler equation in cylindrical coordinates. The numerical results agree qualitatively with the experimental observations of the appearance and growth of large bubble clouds at the smallest laser excitation rings. Our technique of shock-driven bubble cavitation opens interesting perspectives for the investigation of shock-induced single-bubble or multibubble cavitation phenomena in thin liquids.

The effectiveness of simethicone in improving visibility during colonoscopy.

PubMed

Park, Jae Jun; Lee, Sang Kil; Jang, Jae Young; Kim, Hyo Jong; Kim, Nam Hoon

2009-01-01

In colonoscopy examination, luminal visibility is frequently limited due to intraluminal bubbles. In present study was evaluated factors affecting bubble formation and the effects of simethicone in preventing bubble formation during colonoscopy. Consecutive patients (n=164) who received polyethylene glycol or sodium phosphate for bowel preparation were prospectively enrolled. Before colonoscopy, 57 patients took 80 mg simethicone after ingestion of bowel preparation solution and 107 did not to determine whether simethicone decreased bubble formation. Intraluminal gas bubbles were assessed and graded as follows: 0, minimal or none; 1, covering less than half the lumen; 2, covering at least half the lumen or the entire circumference. Grade 2 bubbles were regarded as significant, limiting visibility. Sodium phosphate preparation tended to have more bubbles than the polyethylene glycol. Significant bubbles were more likely to occur in males than females (p = 0.020). Significant bubbles were noted in 34.6% of patients without simethicone and 7% of patients with simethicone. Simethicone significantly lowered the incidence of bubbles during colonoscopy when given after a preparation solution (p < 0.05), The present study findings indicate that taking simethicone after an oral polyethylene glycol or sodium phosphate preparation can improve colonic visibility by diminishing colonic bubbles.

Prediction of Cavitation Depth in an Al-Cu Alloy Melt with Bubble Characteristics Based on Synchrotron X-ray Radiography

NASA Astrophysics Data System (ADS)

Huang, Haijun; Shu, Da; Fu, Yanan; Zhu, Guoliang; Wang, Donghong; Dong, Anping; Sun, Baode

2018-04-01

The size of cavitation region is a key parameter to estimate the metallurgical effect of ultrasonic melt treatment (UST) on preferential structure refinement. We present a simple numerical model to predict the characteristic length of the cavitation region, termed cavitation depth, in a metal melt. The model is based on wave propagation with acoustic attenuation caused by cavitation bubbles which are dependent on bubble characteristics and ultrasonic intensity. In situ synchrotron X-ray imaging of cavitation bubbles has been made to quantitatively measure the size of cavitation region and volume fraction and size distribution of cavitation bubbles in an Al-Cu melt. The results show that cavitation bubbles maintain a log-normal size distribution, and the volume fraction of cavitation bubbles obeys a tanh function with the applied ultrasonic intensity. Using the experimental values of bubble characteristics as input, the predicted cavitation depth agrees well with observations except for a slight deviation at higher acoustic intensities. Further analysis shows that the increase of bubble volume and bubble size both leads to higher attenuation by cavitation bubbles, and hence, smaller cavitation depth. The current model offers a guideline to implement UST, especially for structural refinement.

Laser-induced microjet: wavelength and pulse duration effects on bubble and jet generation for drug injection

NASA Astrophysics Data System (ADS)

Jang, Hun-jae; Park, Mi-ae; Sirotkin, Fedir V.; Yoh, Jack J.

2013-12-01

The expansion of the laser-induced bubble is the main mechanism in the developed microjet injector. In this study, Nd:YAG and Er:YAG lasers are used as triggers of the bubble formation. The impact of the laser parameters on the bubble dynamics is studied and the performance of the injector is evaluated. We found that the main cause of the differences in the bubble behavior comes from the pulse duration and wavelength. For Nd:YAG laser, the pulse duration is very short relative to the bubble lifetime making the behavior of the bubble close to that of the cavitation bubble, while in Er:YAG case, the high absorption in the water and long pulse duration change the initial behavior of the bubble making it close to a vapor bubble. The contraction and subsequent rebound are typical for cavitation bubbles in both cases. The results show that the laser-induced microjet injector generates velocity which is sufficient for the drug delivery for both laser beams of different pulse duration. We estimate the typical velocity within 30-80 m/s range and the breakup length to be larger than 1 mm suitable for trans-dermal drug injection.

Characterization of an acoustic cavitation bubble structure at 230 kHz.

PubMed

Thiemann, Andrea; Nowak, Till; Mettin, Robert; Holsteyns, Frank; Lippert, Alexander

2011-03-01

A generic bubble structure in a 230 kHz ultrasonic field is observed in a partly developed standing wave field in water. It is characterized by high-speed imaging, sonoluminescence recordings, and surface cleaning tests. The structure has two distinct bubble populations. Bigger bubbles (much larger than linear resonance size) group on rings in planes parallel to the transducer surface, apparently in locations of driving pressure minima. They slowly rise in a jittering, but synchronous way, and they can have smaller satellite bubbles, thus resembling the arrays of bubbles observed by Miller [D. Miller, Stable arrays of resonant bubbles in a 1-MHz standing-wave acoustic field, J. Acoust. Soc. Am. 62 (1977) 12]. Smaller bubbles (below and near linear resonance size) show a fast "streamer" motion perpendicular to and away from the transducer surface. While the bigger bubbles do not emit light, the smaller bubbles in the streamers show sonoluminescence when they pass the planes of high driving pressure. Both bubble populations exhibit cleaning potential with respect to micro-particles attached to a glass substrate. The respective mechanisms of particle removal, though, might be different. Copyright © 2010 Elsevier B.V. All rights reserved.

Numerical simulation of single bubble dynamics under acoustic travelling waves.

PubMed

Ma, Xiaojian; Huang, Biao; Li, Yikai; Chang, Qing; Qiu, Sicong; Su, Zheng; Fu, Xiaoying; Wang, Guoyu

2018-04-01

The objective of this paper is to apply CLSVOF method to investigate the single bubble dynamics in acoustic travelling waves. The Naiver-Stokes equation considering the acoustic radiation force is proposed and validated to capture the bubble behaviors. And the CLSVOF method, which can capture the continuous geometric properties and satisfies mass conservation, is applied in present work. Firstly, the regime map, depending on the dimensionless acoustic pressure amplitude and acoustic wave number, is constructed to present different bubble behaviors. Then, the time evolution of the bubble oscillation is investigated and analyzed. Finally, the effect of the direction and the damping coefficient of acoustic wave propagation on the bubble behavior are also considered. The numerical results show that the bubble presents distinct oscillation types in acoustic travelling waves, namely, volume oscillation, shape oscillation, and splitting oscillation. For the splitting oscillation, the formation of jet, splitting of bubble, and the rebound of sub-bubbles may lead to substantial increase in pressure fluctuations on the boundary. For the shape oscillation, the nodes and antinodes of the acoustic pressure wave contribute to the formation of the "cross shape" of the bubble. It should be noted that the direction of the bubble translation and bubble jet are always towards the direction of wave propagation. In addition, the damping coefficient causes bubble in shape oscillation to be of asymmetry in shape and inequality in size, and delays the splitting process. Copyright © 2017 Elsevier B.V. All rights reserved.

Simulation of gas bubbles in hypobaric decompressions: roles of O2, CO2, and H2O.

PubMed

Van Liew, H D; Burkard, M E

1995-01-01

To gain insight into the special features of bubbles that may form in aviators and astronauts, we simulated the growth and decay of bubbles in two hypobaric decompressions and a hyperbaric one, all with the same tissue ratio (TR), where TR is defined as tissue PN2 before decompression divided by barometric pressure after. We used an equation system which is solved by numerical methods and accounts for simultaneous diffusion of any number of gases as well as other major determinants of bubble growth and absorption. We also considered two extremes of the number of bubbles which form per unit of tissue. A) Because physiological mechanisms keep the partial pressures of the "metabolic" gases (O2, CO2, and H2O) nearly constant over a range of hypobaric pressures, their fractions in bubbles are inversely proportional to pressure and their large volumes at low pressure add to bubble size. B) In addition, the large fractions facilitate the entry of N2 into bubbles, and when bubble density is low, enhance an autocatalytic feedback on bubble growth due to increasing surface area. C) The TR is not closely related to bubble size; that is when two different decompressions have the same TR, metabolic gases cause bubbles to grow larger at lower hypobaric pressures. We conclude that the constancy of partial pressures of metabolic gases, unimportant in hyperbaric decompressions, affects bubble size in hypobaric decompressions in inverse relation to the exposure pressure.

Bubble dynamics inside an outgassing hydrogel confined in a Hele-Shaw cell.

PubMed

Haudin, Florence; Noblin, Xavier; Bouret, Yann; Argentina, Médéric; Raufaste, Christophe

2016-08-01

We report an experimental study of bubble dynamics in a non-Newtonian fluid subjected to a pressure decrease. The fluid is a hydrogel, composed of water and a synthetic clay, prepared and sandwiched between two glass plates in a Hele-Shaw geometry. The rheological properties of the material can be tuned by the clay concentration. As the imposed pressure decreases, the gas initially dissolved in the hydrogel triggers bubble formation. Different stages of the process are observed: bubble nucleation, growth, interaction, and creation of domains by bubble contact or coalescence. Initially bubble behave independently. They are trapped and advected by the mean deformation of the hydrogel, and the bubble growth is mainly driven by the diffusion of the dissolved gas through the hydrogel and its outgassing at the reactive-advected hydrogel-bubble interface. In this regime, the rheology of the fluid does not play a significant role on the bubble growth. A model is proposed and gives a simple scaling that relates the bubble growth rate and the imposed pressure. Carbon dioxide is shown to be the gas at play, and the hydrogel is degassing at the millimeter scale as a water solution does at a smaller scale. Later, bubbles are not independent anymore. The growth rate decreases, and the morphology becomes more anisotropic as bubbles interact because they are separated by a distance smaller than the individual stress field extension. Our measurements show that the interaction distance scales with the bubbles' size.