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1

Combining two semidwarfing genes d60 and sd1 for reduced height in 'Minihikari', a new rice germplasm in the 'Koshihikari' genetic background.  

PubMed

Dwarfing in rice has dramatically improved and stabilized rice yields worldwide, often controlled by a single dwarf gene, sd1. A novel semidwarf gene d60 complements the gametic lethal gene gal, such that the F(1) between 'Hokuriku 100' (genotype d60d60GalGal, Gal: mutant non-lethal allele) and 'Koshihikari' (D60D60galgal, D60: tall allele) would show 25% sterility due to deterioration of gametes bearing both gal and d60. The F(2) would segregate as one semidwarf (1 d60d60GalGal) : two tall and 25% sterile (2 D60d60Galgal) : six tall (2 D60d60GalGal : 1 D60D60GalGal : 2 D60D60Galgal : 1 D60D60galgal), skewed from a Mendelian segregation ratio of one semidwarf : three tall for a single recessive gene. To pyramid d60 and sd1, into the Japanese super-variety 'Koshihikari', the F(1) (D60d60Galgal) of 'Koshihikari' 'Hokuriku 100' was first backcrossed with 'Koshihikari', and the BCF(1) segregated into a ratio of one tall and 25% sterile (D60d60Galgal) : two tall (1 D60D60Galgal : 1 D60D60galgal). Tall, 25% sterile BC(1)F(1) plants (D60d60Galgal) were then selected for pollen sterility and backcrossed with 'Koshihikari' as the recurrent parent. It is unnecessary to grow out and select a semidwarf from the BC(n)F(2) if a pollen parent with ~70% pollen fertility is chosen from the BC(n)F(1) to backcross with the recurrent parent. Semidwarfing genes d60 and sd1 were successfully pyramided into the 'Koshihikari' genome by crossing isogenic lines 'Koshihikari d60' and 'Koshihikari sd1', to produce 'Minihikari', a new parental source of both d60 and sd1. 'Minihikari' displayed super-short stature due to the combination of sd1 and d60, which are genetically and functionally independent. PMID:23298446

Tomita, Motonori

2012-10-01

2

Biochemical characterisation of the D60A mutant of the elongation factor 1alpha from the archaeon Sulfolobus solfataricus.  

PubMed

The D60A mutant of the elongation factor (EF) 1alpha from Sulfolobus solfataricus (Ss), was obtained as heterologous expressed protein and characterised. This substitution was carried out in order to analyse the involvement of this evolutionally conserved amino acid position in the interaction between the elongation factor and guanosine nucleotides and in the coordination of magnesium ions. The expression system used produced a folded protein able to catalyse, although to a slightly lower extent with respect to the wild-type enzyme, protein synthesis in vitro and NaCl-dependent intrinsic GTPase activity. The affinity for guanosine nucleotides was almost identical to that exhibited by wild-type SsEF-1alpha; vice versa, the GDP exchange rate was one order of magnitude faster on the mutated elongation factor, a property partially restored when the exchange reaction was analysed in the presence of the magnesium ions chelating agent EDTA. Finally, the D60A substitution only a little affected the high thermal stability of the elongation factor. From a structural point of view, the analysis of the data reported confirmed that this conserved carboxyl group belongs to a protein region differentiating the GDP binding mode among elongation factors from different organisms. PMID:19375481

Ruggiero, Immacolata; Cantiello, Piergiuseppe; Lamberti, Anna; Sorrentino, Angela; Martucci, Nicola M; Ruggiero, Alessia; Arcone, Rosaria; Vitagliano, Luigi; Arcari, Paolo; Masullo, Mariorosario

2009-07-01

3

Acta Cryst. (2004). D60, 613615 DOI: 10.1107/S0907444904000861 613 short communications  

E-print Network

no3, r1no3sf. 1. Introduction Lipoxygenases (LOXs) are known for their ability to metabolize-mediated transformations of natural polyphenolic compounds such as curcumin (Skrzypczak-Jankun et al., 2003) and quercetin

Jankun, Jerzy

4

CYP2D60 and Clinical Response to Atomoxetine in Children and Adolescents with ADHD  

ERIC Educational Resources Information Center

Background: Atomoxetine, a selective norepinephrine reuptake inhibitor effective in the treatment of attention-deficit/hyperactivity disorder (ADHD), is metabolized through the cytochrome P-450 2D6 (CYP2D6) enzyme pathway, which is genetically polymorphic in humans. Variations in plasma atomoxetine exposures can occur because of genetic variation

Michelson, David; Read, Holly A.; Ruff, Dustin D.; Witcher, Jennifer; Zhang, Shuyu; McCracken, James

2007-01-01

5

research papers Acta Cryst. (2004). D60, 21692183 doi:10.1107/S0907444904016038 2169  

E-print Network

of Cambridge, Department of Haematology, Cambridge Institute for Medical Research, Wellcome Trust/MRC Building. Introduction Maximum likelihood is a branch of statistical inference that asserts that the best hypothesis (i.e. set of parameters, which includes estimates of the errors) on the evidence of the data is the one

Hill, Chris

6

Improved hippocampal dose with reduced margin radiotherapy for glioblastoma multiforme  

PubMed Central

Background To dosimetrically evaluate the effect of reduced margin radiotherapy on hippocampal dose for glioblastoma multiforme (GBM) patients. Methods GBM patients enrolled on the Radiation Therapy Oncology Group (RTOG) 0825 trial at our institution were identified. Standard RTOG 0825 expansions were 2cm?+?3-5mm from the gross tumor volume (GTV) to the clinical tumor volume (CTV) and from the CTV to the planning tumor volume (PTV), respectively. These same patients also had reduced margin tumor volumes generated with 8mm (GTV to CTV)?+?3mm (CTV to PTV) expansions. Individual plans were created for both standard and reduced margin structures. The dose-volume histograms were statistically compared with a paired, two-tailed Students t-test with a significance level of p?D60% was reduced from 32.7Gy to 18.7Gy (42.9%) and the D80% was reduced from 27.3Gy to 15.3Gy (44%). Conclusions The use of reduced margin PTV expansions in the treatment of GBM patients results in significant reductions in hippocampal dose. Though the exact clinical benefit of this reduction is currently unclear, this study does provide support for a future prospective trial evaluating the neurocognitive benefits of reduced margin tumor volumes in the treatment of GBM patients. PMID:24411020

2014-01-01

7

AC 2011-1335: STUDENTS AND SUSTAINABILITY: ASSESSING STU-DENTS' UNDERSTANDING OF SUSTAINABILITY FROM SERVICE LEARN-  

E-print Network

in the Environmental Engineering division of ASEE (2001-2005). Dr. Swan's current interests lie in the areas of waste as Director of Michi- gan Tech's D80 Center (www.d80.mtu.edu), a consortium of 20 research, education of Project-Based Service Learning on Engineering Education, Engineering in Developing Communities: Water

8

Companion Gaming: Improving the Quality of Gaming Experiences through Interconnected Gameplay  

E-print Network

.D. .................................................................... 59 Figure 17 Concept art for environments in Titan, Ph.D. .......................................... 60 Figure 18 Screenshots of Titan, Ph.D. ..................................................................... 61 Figure 19 Sketch for Velox...

Ross, Jacob

2013-08-30

9

Volume 131, Number 49 tech.mit.edu Tuesday, November 1, 2011 Oldest and Largest  

E-print Network

a suicide. Chancellor Eric Grimson PhD '80 ad- dressed MIT regarding the deaths in a cam- puswide email last how genetic information is translated into cell structures without changing the genes themselves. Last

10

Influence Of Recruitment Methods On Couple Involvement In Transition To Parenthood Intervention  

E-print Network

(d > .80) on measures of relationship functioning and satisfaction after treatment (Shadish & Baldwin, 2005). In addition, marital therapy is also effective in reducing depression (Gupta et al., 2003) and increasing physical health (Osterman et al... (d > .80) on measures of relationship functioning and satisfaction after treatment (Shadish & Baldwin, 2005). In addition, marital therapy is also effective in reducing depression (Gupta et al., 2003) and increasing physical health (Osterman et al...

Coca, Vanessa Albina

2009-09-30

11

Modeling the liquid-phase oxidation of hydrocarbons over a range of temperatures and dissolved oxygen concentrations with pseudo-detailed chemical kinetics  

Microsoft Academic Search

The ability of pseudo-detailed chemical kinetic modeling to simulate the oxidation behavior of Exxsol D-80, a paraffin blend whose oxidative characteristics are representative of severely hydrotreated jet fuels, is assessed. The effects of temperature and initial dissolved O2 concentration on oxidation are considered. A 17-step pseudo-detailed mechanism is shown to provide reasonable simulations of Exxsol D-80 oxidation over a range

Nicholas J. Kuprowicz; Jamie S. Ervin; Steven Zabarnick

2004-01-01

12

2 EE 692 Advanced Electromagnetics 3 Spring 2009, 3-0 (3 credit hours)  

E-print Network

) Stratton J., "Electromagnetic Theory" (Wiley-IEEE Press, 2007) Harrington R. F., "Time the textbook. 0 Suggested 1 References: Collin R. E., "Field Theory of Guided Waves", (Wiley-IEEE Press, 1990, 69 > D > 60, F

Anagnostou, Dimitris E.

13

19 CFR 148.43 - Tobacco products and alcoholic beverages.  

Code of Federal Regulations, 2010 CFR

19 Customs Duties 2 2010-04-01 2010-04-01...Tariff Schedule of the United States (HTSUS) (19 U.S.C. 1202), when brought in by...43 FR 49789, Oct. 25, 1978; T.D. 80-19, 45 FR 45580, July 7, 1980; T.D....

2010-04-01

14

Table of Contents Comm. Survey 1  

E-print Network

of restorative dentistry. (Photo Mark Mitchell) Top-out is this month! (Photo Sydney Clevenger) Dean Emeritus Smith, D.M.D. `80 (right). Assistant Professor of Restorative Dentistry Donald Sirianni, D.M.D. `64, who OHSU School of Dentistry is analyzing its communications for dental students, staff, faculty

Chapman, Michael S.

15

Passive control of wake flow by two small control cylinders at Reynolds number 80  

Microsoft Academic Search

Passive control of the wake behind a circular cylinder in uniform flow is studied by numerical simulation at ReD=80. Two small control cylinders are placed symmetrically along the separating shear layers at various stream locations. In the present study, the detailed flow mechanisms that lead to a significant reduction in the fluctuating lift but maintain the shedding vortex street are

C.-H. Kuo; C.-C. Chen

2009-01-01

16

Chemical Influence on the Formation, Agglomeration, and Natural Transportability of Gas Hydrates. A Multivariate Component Analysis  

Microsoft Academic Search

This study has focused on chemical components in two paraffinic oil phases, expected to have an influence on the properties of gas hydrates regarding formation, agglomeration, and natural transportability. Crude oil, toluene, wax, and naphtenic acids were selected for this purpose. Two paraffinic phases were used; n?decane and Exxsol D?80, the latter containing surface active material. The experiments were performed

Linn Bergfldt; Lars Henrik Gjertsen; Johan Sjblom; Harald Kallevik; Gisle ye

2004-01-01

17

Corn grain and liquid feed as nonfiber carbohydrate sources in diets for lactating dairy cows 1  

Microsoft Academic Search

Interactions of sources and processing methods for nonstructural carbohydrates may affect the efficiency of animal production. Five rumen-cannulated cows in late lactation were placed in a 5 5 Latin square design and fed experimental diets for 2 wk. In the production trial, 54 cows were fed the experimental diets for 12 wk beginning at d 60 in milk. Diets

M. L. Eastridge; A. H. Lefeld; A. M. Eilenfeld; P. N. Gott; W. S. Bowen; J. L. Firkins

2011-01-01

18

Switching Transistor  

NASA Technical Reports Server (NTRS)

Westinghouse Electric Corporation's D60T transistors are used primarily as switching devices for controlling high power in electrical circuits. It enables reduction in the number and size of circuit components and promotes more efficient use of energy. Wide range of application from a popcorn popper to a radio frequency generator for solar cell production.

1981-01-01

19

Regulation of Porcine Conceptus Survival and Growth by L-arginine  

E-print Network

kg of a corn- and soybean meal-based diet supplemented with 0.0%, 0.4%, or 0.8% L-arginine (w/w) between d 0 and 25 of gestation (Experiment 1) or between d 14 and 25 of gestation (Experiments 2 and 3). At d 25 (Experiment 1 and 2) or d 60 (Experiment...

Li, Xilong

2012-02-14

20

Spring 2009 Syllabus for INSC201: Energy! Information  

E-print Network

in Blackboard (see In-Class Participation). Grading Policy 15 % In-class Participation (each lecture worth ~0.0-89.9%, C: 70.0-79.9%, D: 60.0-69.9%, and F: Class Participation 15 % No excused absences Three will answer using a CPS "clicker". Your participation grade will be based on clicking in answers throughout

Baski, Alison

21

29 CFR 776.6 - Coverage not dependent on place of work.  

Code of Federal Regulations, 2010 CFR

...perform their work at home, in the factory, or elsewhere. 18 The specific provisions of the Act relative to regulation of homework serve to emphasize this fact. 19 18 Walling v. American Needlecrafts, 139 F. 2d 60 (C.A. 6); Walling...

2010-07-01

22

29 CFR 776.6 - Coverage not dependent on place of work.  

...perform their work at home, in the factory, or elsewhere. 18 The specific provisions of the Act relative to regulation of homework serve to emphasize this fact. 19 18 Walling v. American Needlecrafts, 139 F. 2d 60 (C.A. 6); Walling...

2014-07-01

23

29 CFR 776.6 - Coverage not dependent on place of work.  

Code of Federal Regulations, 2012 CFR

...perform their work at home, in the factory, or elsewhere. 18 The specific provisions of the Act relative to regulation of homework serve to emphasize this fact. 19 18 Walling v. American Needlecrafts, 139 F. 2d 60 (C.A. 6); Walling...

2012-07-01

24

29 CFR 776.6 - Coverage not dependent on place of work.  

Code of Federal Regulations, 2011 CFR

...perform their work at home, in the factory, or elsewhere. 18 The specific provisions of the Act relative to regulation of homework serve to emphasize this fact. 19 18 Walling v. American Needlecrafts, 139 F. 2d 60 (C.A. 6); Walling...

2011-07-01

25

29 CFR 776.6 - Coverage not dependent on place of work.  

Code of Federal Regulations, 2013 CFR

...perform their work at home, in the factory, or elsewhere. 18 The specific provisions of the Act relative to regulation of homework serve to emphasize this fact. 19 18 Walling v. American Needlecrafts, 139 F. 2d 60 (C.A. 6); Walling...

2013-07-01

26

Advanced Plant Propagation (PLS 5222 , 3 credits)  

E-print Network

-72% C- 67-69% D+ 63-66% D 60-62% D- 59% E Page 2Advanced Plant Propagation 2012 Please feel free to stopAdvanced Plant Propagation 2012 (PLS 5222 , 3 credits) Course Instructors: Dr. Sandy Wilson. Hartmann and Kester's Plant Propagation: Prin- ciples and Practices. Eighth edi- tion. Prentice-Hall, Inc

Watson, Craig A.

27

Pre-Clinical Radiation Biology and Medical Physics Divisions  

E-print Network

over Time TBI: H-ARS 7.0-9.0Gy; GI-ARS 9.0-13.0Gy WTLI: whole thorax lung irradiation, 9.0-12.5Gy; Recent studies performed in the rhesus macaque TBI: H-ARS dose range, d60, n=48 TBI: GI-ARS dose range

28

GREQAMGroupement de Recherche en Economie Quantitative d'Aix-Marseille -UMR-CNRS 6579  

E-print Network

then discuss the ethical dilemma introduced by the autonomy proviso, which prevents anyone from adopting, when brought together, these two propositions provide a fruitful way of approaching this ethical issue'une manière très profitable. CLASSIFICATION JEL : B11. B31. D60 MOTS-CLEFS : Rousseau ; Freedom ; Ethics

Boyer, Edmond

29

Mathematics Competition  

E-print Network

are not sure, ask your teacher to explain it. 4. This is a multiple-choice test. Each question is followed choice, enter the appropriate letter for that question on your answer sheet. 5. Scoring: Each correct of x? (A) 110 (B) 50 (C) 10 (D) 60 (E) 70 60 50 x 9. The word BANK is painted exactly as shown

Le Roy, Robert J.

30

Syllabus OCB 3043L Marine Biology & Oceanography Lab; Spring 2007 Richard Y. Chang  

E-print Network

, any mistakes that occurred, and interesting observations, which you will need to write up the lab-69 D+; 63-66 D; 60-62 D-; 0-59 F #12;Date Topic Experiments / Activities Notes 12 Jan Scientific and scientific method. 26 Jan Bacteria Bacteria plate counts and staining Topic and expectations for research

Jochem, Frank J.

31

Mathematics Competition  

E-print Network

) 57 (B) 37 (C) 47 (D) 60 (E) 17 D CB A 93o 130o 9. A movie theatre has eleven rows of seats. The rows seats are there in the theatre? (A) 176 (B) 186 (C) 165 (D) 170 (E) 171 #12;Grade 7 10. In relation

Le Roy, Robert J.

32

Experimental research on bitumen preheating (fluidization) by using solar energy in passive mode  

Microsoft Academic Search

An important aim of worldwide research engineering is to identify new industries to introduce solar energy installations for average thermal level.Due to the mechanical and thermal properties of bitumen, such as the 4449?C softening point of D80\\/100 type bitumen, this material can be preheated by using solar thermal installations.The Physics Department of Politehnica University of Timisoara designed and studied a

Ioan Luminosu; Laurentiu Fara

2009-01-01

33

CptSCptS 5 6 1 / E E 5 2 45 6 1 / E E 5 2 4 CCOMPUTEROMPUTER AARCHITECTURERCHITECTURE  

E-print Network

B+ 70 ­ 72.999 C- 83 ­ 86.999 B 60 ­ 69.999 D 80 ­ 82.999 B- Below 60 F #12;EE 524 / CptS 561 10José / CptS 561 9José Delgado-Frias Grade 95 ­ 100 A 77 ­ 79.999 C+ 90 ­ 94.999 A- 73 ­ 76.999 C 87 ­ 89.999

Delgado-Frias, José G.

34

School of Electrical Engineering and Computer Science WASHINGTON STATE UNIVERSITY  

E-print Network

13 Grade 95 ­ 100 A 77 ­ 79.999 C+ 90 ­ 94.999 A- 73 ­ 76.999 C 87 ­ 89.999 B+ 70 ­ 72.999 C- 83 ­ 86.999 B 60 ­ 69.999 D 80 ­ 82.999 B- Below 60 F #12;José Delgado-Frias EE 334 14 Basic components

Delgado-Frias, José G.

35

1003. A source containing a mixture of two isotopes of the same ele-ment emits light at two wavelengths whose average value is 495  

E-print Network

) its frequency d) its wavelength e) its speed 19. A concave mirror forms a real image which is twice be about: a) 27 cm b) 40 cm c) 20 cm d) 80 cm e) 13 cm 20. A concave mirror has focal length f > 0. A real object is placed a distance 2f from the mirror. Then the image is a) Real; inverted; same size as object

Coleman, Piers

36

Table 1. Summary of retrap and recovery results for 2003-4 Spp Name Retraps Recovs Max Dist Max Time  

E-print Network

Heron Ardea purpurea 1 0 0 0y 0m 20d 61 Cattle Egret Bubulcus ibis 0 1 0 0y 0m 5d 73 Marabou Stork Leptoptilos crumeniferus 1 0 480 0y 8m 3d 80 White Stork Ciconia ciconia 22 1 9681 3y 7m 27d 81 Sacred Ibis Threskiornis aethiopicus 34 15 30 1y 2m 5d 84 Hadada Ibis Bostrychia hagedash 0 1 0 y m 5d 86 Greater Flamingo

de Villiers, Marienne

37

Electrokinetic dewatering of Turkish glass sand plant tailings  

Microsoft Academic Search

In this study, the dewatering of glass sand plant tailings from Mersin, Turkey was investigated using an electrokinetic technique. The particle size (d80) of the solid waste material tested was less than 0.020mm and consisted mainly of silica, orthoclase, alumina, potassium and iron oxides. In current plant practice, Larox high-pressure filters are used to produce a filter cake containing 2225%

O. Bayat; O. Kilic; B. Bayat; M. Anil; H. Akarsu; C. Poole

2006-01-01

38

Effect of beef cattle manure application rate on CH4 and CO2 emissions  

NASA Astrophysics Data System (ADS)

In a series of field experiments, emissions of two major greenhouse gases (GHGs), methane (CH4) and carbon dioxide (CO2) were measured using a closed chamber technique in summer 2010 to evaluate the effects of solid beef cattle manure land application techniques. The treatments included a control (C: no manure), two manure application rates (40 and 80 T ha-1), and two injection layers (surface vs. subsurface (5 cm)): (1) 40 T ha-1 on surface (S40), (2) 80 T ha-1 on surface (S80), (3) 40 T ha-1 at subsurface (D40), and (4) 80 T ha-1 at subsurface (D80)). The exchange patterns of CH4 and CO2 in the control were variable and showed both emission and deposition. However, only emissions were seen in the manure treatments. Emissions of CH4 were seen systematically on the ascending order of 5.35 (C), 59.3 (S40), 68.7 (D40), 188 (S80), and 208 ?g m-2 h-1 (D80), while those of CO2 also showed a similar trend: 12.9 (C), 37.6 (S40), 55.8 (D40), 82.4 (S80), and 95.4 mg m-2 h-1 (D80). The overall results of our study suggest that the emissions of CH4 and CO2 are affected most noticeably by the differences in the amount of manure application.

Phan, Nhu-Thuc; Kim, Ki-Hyun; Parker, David; Jeon, Eui-Chan; Sa, Jae-Hwan; Cho, Chang-Sang

2012-12-01

39

Mathematics Competition  

E-print Network

are told to do so. 2. You may use rulers, compasses and paper for rough work. 3. Be sure that you, print your school name, city/town, and province in the box in the upper left corner. 5. Be certain that he can play in 3 hours? (A) 100 (B) 36 (C) 56 (D) 60 (E) 45 9. In the diagram, any may be moved

Le Roy, Robert J.

40

Comment on "High-order contamination in the tail of gravitational collapse''  

E-print Network

We confront the predictions of S. Hod, Phys. Rev. D 60, 104053 (1999) for the late-time decay rate of black hole perturbations with numerical data. Specifically, we ask two questions: First, are corrections to the Price tail dominated by logarithmic terms, as predicted by Hod? Second, if there were logarithmic correction terms, do they take the specific form predicted in Hod's paper? The answer to both questions is ``no.''

Alexander Z. Smith; Lior M. Burko

2005-10-03

41

Mathematics Competition  

E-print Network

) 96 (C) 120 (D) 60 (E) 108 x 3x 6x P Q R 7. The mean (average) of 5 consecutive integers is 9. What + 4 (E) y = -3x + 4 10. There are 400 students at Pascal H.S., where the ratio of boys to girls is 3 : 2. There are 600 students at Fermat C.I., where the ratio of boys to girls is 2 : 3. When

Le Roy, Robert J.

42

Improving Biology Performance with Workshop Groups  

Microsoft Academic Search

This 2-year quasi-experiment evaluated the effect of peer-led workshop groups on perfor- mance of minority and majority undergraduate biology students. The workshop intervention used was modeled after a program pioneered by Treisman (1992). Majority volunteers ran- domly assigned to workshops (nD 61) performed significantly better than those assigned to the control group (nD 60, p< 0:05) without spending more time

Wendi K. Born; William Revelle; Lawrence H. Pinto

2002-01-01

43

Introduction to Weather and Climate Lab L1 Monday, 2:00-4:40 pm Nat. Res. 108  

E-print Network

will be posted on the ATS351 RamCT page. Grading Lab handouts (13~14) will comprise most of your grade in ATS351. No greater than 2 hours of effort outside of lab lectures should be expected for this course. Most lab amount of your final grade (as extra credit). A: 90­100 B: 80­89 C: 70­79 D: 60­69 F: Below 60 #12;Class

44

SYLLABUS for INSC310 (Content of Elementary Science, Spring 2008) Information  

E-print Network

it online in Blackboard (see In-Class Participation). There is no required textbook for this course. Copies.0-100%, B: 80.0-89.9%, C: 70.0-79.9%, D: 60.0-69.9%, and F: Class Participation 25% Attendance of the lecture notes will be handed out and will also be available in LON-CAPA. Grading Policy 25 % In-Class

Baski, Alison

45

Solutions 2002 Gauss Contest -Grade 8 1. The value of  

E-print Network

Solutions 2002 Gauss Contest - Grade 8 9 Part A 1. The value of 1 2 1 4 + is (A) 1 (B) 1 8 (C) 1 6 (D) 2 6 (E) 3 4 Solution Using a common denominator, 1 2 1 4 2 4 1 4 3 4 + = + = . ANSWER: (E) 2. The expression 6 1000 5 100 6 1¥ + ¥ + ¥ is equivalent to (A) 656 (B) 6506 (C) 6056 (D) 60 506 (E) 6560 Solution

Le Roy, Robert J.

46

High-frequency plant regeneration from seed-derived callus cultures of Kentucky bluegrass ( Poa pratensis L.)  

Microsoft Academic Search

Shoot regeneration from seed-derived callus cultures of Kentucky bluegrass (Poa pratensis L.) was tested on MS basal medium supplemented with four different growth regulators. Regeneration frequencies for medium supplemented with 10 M 2,4-dichlorophenoxyacetic acid (2,4-D), 60 M 4amino-3, 5,6-picolinic acid (picloram), or 30 M 3,6dichloro-o-anisic acid (dicamba) ranged from 0.4 to 4%. Medium supplemented with 30 M dicamba plus 10

Jeffrey D. Griffin; Margaret S. Dibble

1995-01-01

47

Descending Facilitation Maintains Long-term Spontaneous Neuropathic Pain  

PubMed Central

Neuropathic pain is frequently characterized by spontaneous pain (i.e. pain at rest) and in some cases, cold and touch-induced allodynia. Mechanisms underlying the chronicity of neuropathic pain are not well understood. Rats received spinal nerve ligation (SNL) and were monitored for tactile and thermal thresholds. While heat hypersensitivity returned to baseline levels within approximately 35-40 days tactile hypersensitivity was still present at 580 days after SNL. Tactile hypersensitivity at post-SNL day 60 (D60) was reversed by microinjection of (a) lidocaine or (b) a CCK2 receptor antagonist into the rostral ventromedial medulla (RVM) or (c) dorsolateral funiculus (DLF) lesion. RVM lidocaine at D60 or spinal ondansetron, a 5HT3 antagonist, at post-SNL day 42 produced conditioned place preference (CPP) selectively in SNL treated rats, suggesting long-lasting spontaneous pain. Touch-induced FOS was increased in the spinal dorsal horn of SNL rats at D60 and prevented by prior DLF lesion suggesting that long-lasting tactile hypersensitivity depends upon spinal sensitization, which is mediated in part, by descending facilitation, in spite of resolution of heat hypersensitivity. Perspective These data suggest that spontaneous pain is present for an extended period of time and, consistent with likely actions of clinically effective drugs, is maintained by descending facilitation. PMID:23602267

Wang, Ruizhong; King, Tamara; De Felice, Milena; Guo, Wenhong; Ossipov, Michael H.; Porreca, Frank

2014-01-01

48

Simultaneous and successive inoculations of yeasts and lactic acid bacteria on the fermentation of an unsulfited Tannat grape must  

PubMed Central

Interactions between yeasts and lactic acid bacteria are strain specific, and their outcome is expected to change in simultaneous alcoholic - malolactic fermentations from the pattern observed in successive fermentations. One Oenococcus oeni strain Lalvin VP41 was inoculated with two Saccharomyces cerevisiae strains either simultaneously, three days after the yeast inoculation, or when alcoholic fermentation was close to finish. Early bacterial inoculations with each yeast strain allowed for the growth of the bacterial populations, and the length of malolactic fermentation was reduced to six days. Alcoholic fermentation by Lalvin ICV D80 yeast strain left the highest residual sugar, suggesting a negative effect of the bacterial growth and malolactic activity on its performance. In sequential inoculations the bacterial populations did not show actual growth with either yeast strain. In this strategy, both yeast strains finished the alcoholic fermentations, and malolactic fermentations took longer to finish. Lalvin ICV D80 allowed for higher viability and activity of the bacterial strain than Fermicru UY4 under the three inoculation strategies. This was beneficial for the sequential completion of both fermentations, but negatively affected the completion of alcoholic fermentation by Lalvin ICV D80 in the early bacteria additions. Conversely, Fermicru UY4, which was rather inhibitory towards the bacteria, favored the timely completion of both fermentations simultaneously. As bacteria in early inoculations with low or no SO2 addition can be expected to multiply and interact with fermenting yeasts, not only are the yeast-bacterium strains combination and time point of the inoculation to be considered, but also the amount of bacteria inoculated. PMID:24948914

Munoz, Viviana; Beccaria, Bruno; Abreo, Eduardo

2014-01-01

49

High Voltage TAL Erosion Characterization  

NASA Technical Reports Server (NTRS)

Extended operation of a D-80 anode layer thruster at high voltage was investigated. The thruster was operated for 1200 hours at 700 Volts and 4 Amperes. Laser profilometry was employed to quantify the erosion of the thruster's graphite guard rings and electrodes at 0, 300, 600, 900, and 1200 hours. Thruster performance and electrical characteristics were monitored over the duration of the investigation. The guard rings exhibited asymmetric erosion that was greatest in the region of the cathode. Erosion of the guard rings exposed the magnet poles between 600 to 900 hours of operation.

Jacobson, David T.

2003-01-01

50

SISTEMA BIBLIOTECARIO SAPIENZA Graduatoria concorso n. 10 borse collaborazione  

E-print Network

,00 25,50 27 91,50 3 ZEI FEDERICO 30,00 29,44 30 89,44 4 MORELLI MARINA 30,00 29,00 30 89,00 5 D 80,37 30 NITTOLI MARIANGELA 25,50 26,12 28 79,62 31 CANDIDI SARA 23,00 26,11 30 79,11 32 STRANO CHIARA 21,00 27,45 30 78,45 33 DI LELLO SARA GRAZIEL 18,00 30,00 30 78,00 34 ROMANO ANNARITA 20,00 27

Guidoni, Leonardo

51

Geodesic structure of Lifshitz black holes in 2+1 dimensions  

NASA Astrophysics Data System (ADS)

We present a study of the geodesic equations of a black hole space-time which is a solution of the three-dimensional NMG theory and is asymptotically Lifshitz with z=3 and d=1 as found in Ayon-Beato et al. (Phys. Rev. D 80:104029, 2009). By means of the corresponding effective potentials for massive particles and photons we find the allowed motions by the energy levels. Exact solutions for radial and non-radial geodesics are given in terms of the Weierstrass elliptic ?, ?, and ? functions.

Cruz, Norman; Olivares, Marco; Villanueva, J. R.

2013-07-01

52

Inhibition of prostate cancer cell growth by second-site androgen receptor antagonists  

PubMed Central

The impact of ligand binding on nuclear receptor (NR) structure and the ability of target cells to distinguish between different receptor-ligand complexes are key determinants of the pharmacological activity of NR ligands. However, until relatively recently, these mechanistic insights have not been used in a prospective manner to develop screens for NR modulators with specific therapeutic activities. Driven by the need for unique androgen receptor (AR) antagonists that retain activity in hormone-refractory prostate cancer, we developed and applied a conformation-based screen to identify AR antagonists that were mechanistically distinct from existing drugs of this class. Two molecules were identified by using this approach, D36 and D80, which interact with AR in a unique manner and allosterically inhibit AR agonist activity. Unlike the clinically important antiandrogens, casodex and hydroxyflutamide, both D36 and D80 block androgen action in cellular models of hormone-refractory prostate cancer. Mechanistically, these compounds further distinguish themselves from classical AR antagonists in that they do not promote AR nuclear translocation and quantitatively inhibit the association of AR with DNA even under conditions of overexpression. Although the therapeutic potential of these antiandrogens is apparent, it is the demonstration that it is possible, to modulate the interaction of cofactors with agonist-activated AR, using second-site modulators, that has the greatest potential with respect to the therapeutic exploitation of AR and other NRs. PMID:19574450

Joseph, James D.; Wittmann, Bryan M.; Dwyer, Mary A.; Cui, Huaxia; Dye, Delita A.; McDonnell, Donald P.; Norris, John D.

2009-01-01

53

Note on the scale evolution of the Efremov-Teryaev-Qiu-Sterman function TF(x,x)  

NASA Astrophysics Data System (ADS)

We reexamine the scale dependence of the Efremov-Teryaev-Qiu-Sterman twist-3 matrix element that has been studied already by the four different groups with conflicting results [Z.-B. Kang and J.-W. Qiu, Phys. Rev. DPRVDAQ1550-7998 79, 016003 (2009)10.1103/PhysRevD.79.016003; J. Zhou, F. Yuan, and Z.-T. Liang, Phys. Rev. DPRVDAQ1550-7998 79, 114022 (2009)10.1103/PhysRevD.79.114022; W. Vogelsang and F. Yuan, Phys. Rev. DPRVDAQ1550-7998 79, 094010 (2009)10.1103/PhysRevD.79.094010; and V. M. Braun, A. N. Manashov, and B. Pirnay, Phys. Rev. DPRVDAQ1550-7998 80, 114002 (2009)10.1103/PhysRevD.80.114002]. We find that we can in fact reproduce the results of V. M. Braun, A. N. Manashov, and B. Pirnay, Phys. Rev. DPRVDAQ1550-7998 80, 114002 (2009)10.1103/PhysRevD.80.114002 with the methods of J. Zhou, F. Yuan, and Z.-T. Liang, Phys. Rev. DPRVDAQ1550-7998 79, 114022 (2009)10.1103/PhysRevD.79.114022 when we treat some subtleties with greater care, thus easing the mentioned conflict.

Schfer, Andreas; Zhou, Jian

2012-06-01

54

3D printed metal columns for capillary liquid chromatography.  

PubMed

Coiled planar capillary chromatography columns (0.9 mm I.D. 60 cm L) were 3D printed in stainless steel (316L), and titanium (Ti-6Al-4V) alloys (external dimensions of ?5 30 58 mm), and either slurry packed with various sized reversed-phase octadecylsilica particles, or filled with an in situ prepared methacrylate based monolith. Coiled printed columns were coupled directly with 30 30 mm Peltier thermoelectric direct contact heater/cooler modules. Preliminary results show the potential of using such 3D printed columns in future portable chromatographic devices. PMID:25285334

Sandron, S; Heery, B; Gupta, V; Collins, D A; Nesterenko, E P; Nesterenko, P N; Talebi, M; Beirne, S; Thompson, F; Wallace, G G; Brabazon, D; Regan, F; Paull, B

2014-11-10

55

Three-body description of direct nuclear reactions: Comparison with the continuum discretized coupled channels method  

E-print Network

The continuum discretized coupled channels (CDCC) method is compared to the exact solution of the three-body Faddeev equations in momentum space. We present results for: i) elastic and breakup observables of d-12C at E_d=56 MeV, ii) elastic scattering of d-58Ni at E_d=80 MeV, and iii) elastic, breakup and transfer observables for 11Be+p at E_{11Be}/A=38.4 MeV. Our comparative studies show that, in the first two cases, the CDCC method is a good approximation to the full three-body Faddeev solution, but for the 11Be exotic nucleus, depending on the observable or the kinematic regime, it may miss out some of the dynamic three-body effects that appear through the explicit coupling to the transfer channel.

Deltuva, A; Cravo, E; Nunes, F M; Fonseca, A C

2007-01-01

56

Three-body description of direct nuclear reactions: Comparison with the continuum discretized coupled channels method  

E-print Network

The continuum discretized coupled channels (CDCC) method is compared to the exact solution of the three-body Faddeev equations in momentum space. We present results for: i) elastic and breakup observables of d-12C at E_d=56 MeV, ii) elastic scattering of d-58Ni at E_d=80 MeV, and iii) elastic, breakup and transfer observables for 11Be+p at E_{11Be}/A=38.4 MeV. Our comparative studies show that, in the first two cases, the CDCC method is a good approximation to the full three-body Faddeev solution, but for the 11Be exotic nucleus, depending on the observable or the kinematic regime, it may miss out some of the dynamic three-body effects that appear through the explicit coupling to the transfer channel.

A. Deltuva; A. M. Moro; E. Cravo; F. M. Nunes; A. C. Fonseca

2007-10-31

57

Three-body description of direct nuclear reactions: Comparison with the continuum discretized coupled channels method  

SciTech Connect

The continuum discretized coupled channels (CDCC) method is compared with the exact solution of the three-body Faddeev equations in momentum space. We present results for (i) elastic and breakup observables of d+{sup 12}C at E{sub d}=56 MeV (ii) elastic scattering of d+{sup 58}Ni at E{sub d}=80 MeV, and (iii) elastic, breakup, and transfer observables for {sup 11}Be+p at E{sub {sup 11}Be}/A=38.4 MeV. Our comparative studies show that in the first two cases, the CDCC method is a good approximation of the full three-body Faddeev solution, but for the {sup 11}Be exotic nucleus, depending on the observable or the kinematic regime, it may miss some of the dynamic three-body effects that appear through the explicit coupling to the transfer channel.

Deltuva, A.; Cravo, E.; Fonseca, A. C. [Centro de Fisica Nuclear da Universidade de Lisboa, P-1649-003 Lisboa (Portugal); Moro, A. M. [Departamento de FAMN, Univ. de Sevilla (Spain); Nunes, F. M. [NSCL and Dept. of Physics and Astronomy, Michigan State University, East Lansing Michigan 48824 (United States)

2007-12-15

58

Genetic diversity and drug resistance of HIV type 1 circulating recombinant Form_BC among drug users in Guangdong Province.  

PubMed

To study genetic diversity and drug resistance of HIV-1 CRF_BC among drug users in Guangdong Province, 67 circulating recombinant form 07_BC (CRF_07BC) and 32 circulating recombinant form 08_BC(CRF_08BC) HIV-1 pol genes were amplified and sequenced. In the protease gene region (PR), 31 CRF_08BC isolates were amplified and 10 high polymorphism positions were identified. The polymorphisms L19I, M36I, R41K, D60E, L63P, H69K, and I93L were complete substitutions, and were followed by T12S (94%), I15V (90%), and L89M (81%) separately. Five high polymorphisms were found in CRF_07BC isolates; there were E35D (88%), R41K (100%), D60E (96%), L63P (99%), and I93L (91%). Four of the identified polymorphism positions (R41K, D60E, L63P, and I93L) were the same in the PR region of both subtypes. In the reverse transcriptase (RT) region six high polymorphism positions, V35T, E36A, T39D/E/N, S48T, V60I, and V245Q, were identified in both subtypes. E53D (97%), I135V/T/R (81%), S162C (94%), Q207E (100%), and R211K (97%) were primarily in CRF_08BC subtypes and D121Y/H (97%) were primarily in CRF_07BC. The NRTI resistance mutation T69S was 94% (30/32) in CRF_08BC. To now, we have found no related reports concerning such high polymorphisms in the position. Polymorphisms V77M (PI) and K201Q (RT) were not found in the mutation profiles; therefore it may have been a new mutation in HIV-1. This study analyzed the difference between CRF_08BC and 07BC polymorphisms among drug users in Guangdong Province, which may help to guide recommendations for diagnostic assays, vaccine design, and antiretroviral regimen strategies in China. PMID:19698024

Yu, Guolong; Li, Yan; Li, Jie; Diao, Limei; Yan, Xinge; Lin, Ping; He, Qun; Wang, Ye; Fu, Xiaobing; Yang, Fang; Long, Qisui; Lin, Peng

2009-09-01

59

Efficacy of Daflon 500 mg in venous leg ulcer healing: a double-blind, randomized, controlled versus placebo trial in 107 patients.  

PubMed

The objective of this study was to evaluate the efficacy of Daflon 500 mg (Dios)* in venous ulcers. A multicenter, double-blind, randomized, controlled versus placebo (Plac) trial was conducted, with stratification according to the size of ulcer (< or = 10 cm and > 10 cm). The protocol called for a two-month treatment with Dios (one tablet = 450 mg micronized purified Diosmin) or a placebo, two tablets/day, in addition to compression therapy. Evaluations were performed every fifteen days, from D0 to D60. The primary endpoint, in accordance with Alexander House group requirements were: percentage of patients with complete ulcer healing, ie, comparison between Dios and Plac group at D60, and comparison of survival curves in each group between D0 and D60 (log rank test). Secondary endpoints included ulcer surface area assessed by computerized planimetric measurements, qualitative evaluation of ulcers, and symptoms. The patients were 105 men and women ranging in age from eighteen to eighty-five years, with standard compression stocking, who were undergoing standardized local care of ulcer and had no significant arterial disease (ankle/arm systolic pressure index > 0.8). Fifty-three patients received Dios, and 52 received Plac. The 2 groups were well matched for age (m +/- 1 SD = seventy-one +/- eleven years), gender, ulcer size, and associated disorders. Among patients with ulcer size < or = 10 cm (Dios = 44, Plac = 47) a significantly larger number of patients had a complete ulcer healing at two months in the Dios group (n = 14) in comparison with the Plac group (n = 6) (32% vs 13%, P = 0.028) with a significantly shorter time duration of healing (P = 0.037). No difference was shown for the secondary criteria, except for sensation of heavy legs (P = 0.039) and a less atonic aspect of ulcer (P = 0.030) in favor of Dios. Among the 14 patients with ulcer size > 10 cm (Dios = 9, Plac = 5), subjected to a descriptive analysis only, no ulcer healed. This study showed that a two-month course of Daflon 500 mg at a daily dose of two tablets, in addition to conventional treatment, is of benefit in patients with venous ulcer < or = 10 cm by accelerating complete healing. PMID:8995348

Guilhou, J J; Dereure, O; Marzin, L; Ouvry, P; Zuccarelli, F; Debure, C; Van Landuyt, H; Gillet-Terver, M N; Guillot, B; Levesque, H; Mignot, J; Pillion, G; Fvrier, B; Dubeaux, D

1997-01-01

60

The effects of stocking density on two Tilapia species raised in an intensive culture system  

E-print Network

0. 15 0. 13 0 ' 22 0. 40 0. 58 0. 78 1. 11 0. 12 0. 24 0. 19 0. 20 0. 25 0. 28 0. 24 14 0. 12 0. 15 0 ' 21 0. 32 0. 67 0. 68 1. 00 0. 10 0. 18 0. 20 0. 15 0. 24 0. 26 0. 26 30 Table 4: Weekly mean water temperature among all experimental tanks... 127. 1 a 121. 9 b 118. 4 c 113. 0 d 115. 2 d 115. 3 d ** 60 liters/tank water volume 35 stocking density had significant effects on fish weight. T. sures were larger overall than T. mossambica, 69. 05 m 16. 9 g as compared to 53. 17 + 11. 1 g...

Henderson-Arzapalo, Anne

2012-06-07

61

Establishment of grass mixtures on roadsides  

E-print Network

Other forbs lob 13 a 7a 9a 38c 4a 6a 7 ab 9b Ib 17 a 7a 46 a 4a t' b 2b 20 a 6 ab 10 a 9a 41 b 12 a 2b 12 a 12 b 4 ab 16 a 6a 44 ab la 3 ab 8 ab 'Values across rows followed by the same letter are not significantly... ab 9a Sa lb 24 a 2a 3b 2b 2b 3a 17 b 1 ab 6a 7a lb 2 ab 18 b t bc 4 ab O~c1 GIR tb tb 1 ab 2a F~rbs lb 1 ab 1 ab 2a L~iter 5c 8 ab 7b 9a B arced 67 a 47 d 60 b 56 c 'Values across rows followed by the same letter...

Simpkins, Cynthia Lynne

2012-06-07

62

Searching for seismo-ionospheric earthquakes precursors: Total Electron Content disturbances before 2005-2006 seismic events  

E-print Network

During earthquakes preparation periods significant disturbances in the ionospheric plasma density are often observed. These anomalies are caused by lithosphere-atmosphere-ionosphere interaction, particularly by the seismic electric field penetrating from the ground surface into the ionosphere. The seismic electric field produces electromagnetic EB drift changing plasma density over the epicenter region and magnetically conjugated area. The paper is devoted to analysis of regular Global Positioning System observations and revelation of seismo-ionospheric precursors of earthquakes in Total Electron Content (TEC) of the ionosphere. Global and regional relative TEC disturbances maps (%) have been plotted for 2005-2006 M6, D<60 km seismic events and analyzed in order to determine general features of precursors. The obtained results agree with the recent published case-study investigations.

Romanovskaya, Yu V; Zolotov, O V; Starikova, N A; Lopatiy, V Z

2012-01-01

63

The effect of caffeine on mammary gland development and milk yield in primiparous sows.  

PubMed

Pregnant Yorkshire gilts (n = 42) were fed caffeine (6 g/d) or served as controls from d 60 of pregnancy until d 4 postpartum to test the effect of caffeine on mammary gland development, milk yield, and feed consumption. Caffeine reduced voluntary feed intake (P = .001) and body weight gain (P = .001) of gilts from d 60 to 109 of gestation. Pig birth weight in the treated group was less than (P = .01) that in the control group. However, pig viability score at birth was not affected by maternal caffeine ingestion. For assessing mammary gland DNA, RNA, dry fat-free tissue (DFFT), fat, and protein content, four sows from the caffeine group and three controls were slaughtered on the 1st d of lactation. Immediately after slaughter, mammary systems were removed, separated by gland, and dissected free of skin, muscle, and fatty pad, which had not been invaded by glandular tissue. The DNA and RNA content were evaluated in DFFT. Caffeine increased mammary RNA content (P = .023) and milk yield (P = .001) on d 1 of lactation. However, DNA, DFFT, fat, and protein were not significantly increased, although values were somewhat greater in the treatment group (approximately 82%). On d 21 of lactation, milk yield of treated sows did not differ from that of controls. The increased milk yield on d 1 of lactation was due to increased mammary epithelial cell activity and cell numbers. These results indicate that caffeine feeding can have a positive effect on porcine mammary gland development as well as milk yield. PMID:7541397

Li, S; Hacker, R R

1995-02-01

64

Engineering Development of Advanced Physical Fine Coal Cleaning for Premium Fuel Applications: Task 9 - Selective agglomeration Module Testing and Evaluation.  

SciTech Connect

The primary goal of this project was the engineering development of two advanced physical fine coal cleaning processes, column flotation and selective agglomeration, for premium fuel applications. The project scope included laboratory research and bench-scale testing of both processes on six coals to optimize the processes, followed by the design, construction, and operation of a 2 t/hr process development unit (PDU). The project began in October, 1992, and is scheduled for completion by September 1997. This report summarizes the findings of all the selective agglomeration (SA) test work performed with emphasis on the results of the PDU SA Module testing. Two light hydrocarbons, heptane and pentane, were tested as agglomerants in the laboratory research program which investigated two reactor design concepts: a conventional two-stage agglomeration circuit and a unitized reactor that combined the high- and low-shear operations in one vessel. The results were used to design and build a 25 lb/hr bench-scale unit with two-stage agglomeration. The unit also included a steam stripping and condensation circuit for recovery and recycle of heptane. It was tested on six coals to determine the optimum grind and other process conditions that resulted in the recovery of about 99% of the energy while producing low ash (1-2 lb/MBtu) products. The fineness of the grind was the most important variable with the D80 (80% passing size) varying in the 12 to 68 micron range. All the clean coals could be formulated into coal-water-slurry-fuels with acceptable properties. The bench-scale results were used for the conceptual and detailed design of the PDU SA Module which was integrated with the existing grinding and dewatering circuits. The PDU was operated for about 9 months. During the first three months, the shakedown testing was performed to fine tune the operation and control of various equipment. This was followed by parametric testing, optimization/confirmatory testing, and finally a 72-hour round the clock production run for each of the three project coals (Hiawatha, Taggart, and Indiana VII). The parametric testing results confirmed that the Taggart coal ground to a D80 of 30 microns could be cleaned to 1 lb ash/MBtu, whereas the Hiawatha and Indiana Vil coals had to be ground to D80s of 40 and 20 microns, respectively, to be cleaned to 2 lb ash/MBtu. The percent solids, residence time, shear intensity (impeller tip speed and energy input per unit volume), and heptane dosage were the main variables that affected successful operation (phase inversion or microagglomerate formation in the high-shear reactor and their growth to 2-3 mm in size during low shear). Downward inclination of the vibrating screen and adequate spray water helped produce the low ash products. Btu recoveries were consistently greater than 98%. Two-stage steam stripping achieved about 99% heptane recovery for recycle to the process. Residual hydrocarbon concentrations were in the 3000 to 5000 ppm range on a dry solids basis.

Moro, N.` Jha, M.C.

1997-09-29

65

Sex Differences in ?-Adrenergic Responsiveness of Action Potentials and Intracellular Calcium Handling in Isolated Rabbit Hearts  

PubMed Central

Cardioprotection in females, as observed in the setting of heart failure, has been attributed to sex differences in intracellular calcium handling and its modulation by ?-adrenergic signaling. However, further studies examining sex differences in ?-adrenergic responsiveness have yielded inconsistent results and have mostly been limited to studies of contractility, ion channel function, or calcium handling alone. Given the close interaction of the action potential (AP) and intracellular calcium transient (CaT) through the process of excitation-contraction coupling, the need for studies exploring the relationship between agonist-induced AP and calcium handling changes in female and male hearts is evident. Thus, the aim of this study was to use optical mapping to examine sex differences in ventricular APs and CaTs measured simultaneously from Langendorff-perfused hearts isolated from nave adult rabbits during ?-adrenergic stimulation. The non-selective ?-agonist isoproterenol (Iso) decreased AP duration (APD90), CaT duration (CaD80), and the decay constant of the CaT (?) in a dose-dependent manner (1316.2 nM), with a plateau at doses ?31.6 nM. The Iso-induced changes in APD90 and ? (but not CaD80) were significantly smaller in female than male hearts. These sex differences were more significant at faster (5.5 Hz) than resting rates (3 Hz). Treatment with Iso led to the development of spontaneous calcium release (SCR) with a dose threshold of 31.6 nM. While SCR occurrence was similar in female (49%) and male (53%) hearts, the associated ectopic beats had a lower frequency of occurrence (16% versus 40%) and higher threshold (100 nM versus 31.6 nM) in female than male hearts (p<0.05). In conclusion, female hearts had a decreased capacity to respond to ?-adrenergic stimulation, particularly under conditions of increased demand (i.e. faster pacing rates and maximal levels of Iso effects), however this reduced ?-adrenergic responsiveness of female hearts was associated with reduced arrhythmic activity. PMID:25340795

Hoeker, Gregory S.; Hood, Ashleigh R.; Katra, Rodolphe P.; Poelzing, Steven; Pogwizd, Steven M.

2014-01-01

66

Effect of core diameter, surface coating, and PEG chain length on the biodistribution of persistent luminescence nanoparticles in mice.  

PubMed

A growing insight toward optical sensors has led to several major improvements in the development of convenient probes for in vivo imaging. Efficient optical detection using quantum dots (QDs) as well as near-infrared organic dyes relies on several key driving principles: the ability to lower background absorption or autofluorescence from tissue, a good photostability of the probe, and a high quantum yield. In this article, we report the real-time biodistribution monitoring of lanthanide-doped persistent luminescence nanoparticles (PLNP), emitting in the near-infrared window, in healthy and tumor-bearing mice. We focused on the influence of hydrodynamic diameter, ranging from 80 to 180 nm, and polyethylene glycol (PEG) surface coating on the behavior of our probes. Tissue distribution was found to be highly dependent on surface coverage as well as core diameter. The amount of PLNP in the blood was highly increased for small (d < 80 nm) and stealth particles. On the opposite, PEG shield molecular weight, ranging from 5 to 20 kDa, had only negligible influence on the in vivo biodistribution of our silicate-based material. PMID:21291197

Maldiney, Thomas; Richard, Cyrille; Seguin, Johanne; Wattier, Nicolas; Bessodes, Michel; Scherman, Daniel

2011-02-22

67

CAPTURE OF TROJANS BY JUMPING JUPITER  

SciTech Connect

Jupiter Trojans are thought to be survivors of a much larger population of planetesimals that existed in the planetary region when planets formed. They can provide important constraints on the mass and properties of the planetesimal disk, and its dispersal during planet migration. Here, we tested a possibility that the Trojans were captured during the early dynamical instability among the outer planets (aka the Nice model), when the semimajor axis of Jupiter was changing as a result of scattering encounters with an ice giant. The capture occurs in this model when Jupiter's orbit and its Lagrange points become radially displaced in a scattering event and fall into a region populated by planetesimals (that previously evolved from their natal transplanetary disk to {approx}5 AU during the instability). Our numerical simulations of the new capture model, hereafter jump capture, satisfactorily reproduce the orbital distribution of the Trojans and their total mass. The jump capture is potentially capable of explaining the observed asymmetry in the number of leading and trailing Trojans. We find that the capture probability is (6-8) Multiplication-Sign 10{sup -7} for each particle in the original transplanetary disk, implying that the disk contained (3-4) Multiplication-Sign 10{sup 7} planetesimals with absolute magnitude H < 9 (corresponding to diameter D = 80 km for a 7% albedo). The disk mass inferred from this work, M{sub disk} {approx} 14-28 M{sub Earth}, is consistent with the mass deduced from recent dynamical simulations of the planetary instability.

Nesvorny, David [Department of Space Studies, Southwest Research Institute, 1050 Walnut St., Suite 300, Boulder, CO 80302 (United States); Vokrouhlicky, David [Institute of Astronomy, Charles University, V Holesovickach 2, 180 00 Prague 8 (Czech Republic); Morbidelli, Alessandro [Departement Cassiopee, University of Nice, CNRS, Observatoire de la Cote d'Azur, Nice, F-06304 (France)

2013-05-01

68

Film cooling from a single row of holes oriented in spanwise/normal planes  

SciTech Connect

Experimental results are presented that describe the development and structure of flow downstream of a single row of film-cooling holes inclined at 30 deg from the test surface in spanwise/normal planes. With this configuration, holes are spaced 6d apart in the spanwise direction in a single row. Results are presented for a ratio of injectant density to free-stream density near 1.0, and injection blowing ratios from 0.5 to 1.5. Compared to results measured downstream of simple angle (streamwise) oriented holes, spanwise-averaged adiabatic effectiveness values are significantly higher for the same spanwise hole spacing, normalized streamwise location x/d, and blowing ratio m when m = 1.0 and 1.5 for x/d < 80. The injectant from the spanwise/normal holes is also less likely to lift off of the test surface than injectant from simple angle holes. This is because lateral components of momentum keep higher concentrations of injectant in closer proximity to the surface. As a result, local adiabatic effectiveness values show significantly greater spanwise variations and higher local maxima at locations immediately downstream of the holes. Spanwise-averaged iso-energetic Stanton number ratios range between 1.07 and 1.26, which are significantly higher than values measured downstream of two other injection configurations (one of which is simple angle, streamwise holes) when compared at the same x/d and blowing ratio.

Ligrani, P.M. [Univ. of Utah, Salt Lake City, UT (United States). Dept. of Mechanical Engineering; Ramsey, A.E. [Naval Postgraduate School, Monterey, CA (United States). Dept. of Mechanical Engineering

1997-10-01

69

Molecular modeling and active site analysis of SdiA homolog, a putative quorum sensor for Salmonella typhimurium pathogenecity reveals specific binding patterns of AHL transcriptional regulators.  

PubMed

Salmonella typhimurium is a Gram-negative bacterium responsible for human diseases including gastroenteritis and typhoid fever and its quorum sensing system is currently being intensively researched. Molecular modeling and binding site analysis of SdiA homolog, a putative quorum sensor of the LuxR family and responsible for S. typhimurium pathogenecity revealed a high structural homology of their active site with three other LuxR family proteins LasR from Pseudomonas aeruginosa, TraR from Agrobacterium tumifaciens and CviR from Chromobacterium violaceum. The results show that all the LuxR family proteins harbor three conserved amino acids Tryptophan (W67) and Aspartic acid (D80) for formation of hydrogen bridges and Tyrosine (Y71) for the hydrophobic interactions (corresponding to their position in S. typhimurium SdiA) with acyl homoserine lactones (AHL)-dependent transcriptional regulators. However, in addition to the above conserved residues, Arginine (R60) also plays an important role in S. typhimurium SdiA binding with its AHL auto inducers and the complex is found to be stronger because of the interactions between nitrogen atoms of Arginine with the carbonyl oxygen in the lactone ring of AHL. The specific binding patterns would be helpful in guiding both enzymatic studies as well as design of specific inhibitors to overcome S. typhimurium pathogenecity. PMID:22660944

Gnanendra, Shanmugam; Anusuya, Shanmugam; Natarajan, Jeyakumar

2012-10-01

70

Emissions from a generator fueled by blends of diesel, biodiesel, acetone, and isopropyl alcohol: analyses of emitted PM, particulate carbon, and PAHs.  

PubMed

Biodiesel is one of alternative energies that have been extensively discussed and studied. This research investigates the characteristics of particulate matter (PM), particulate carbon, and polycyclic aromatic hydrocarbons (PAHs) emitted from a generator fueled by waste-edible-oil-biodiesel with acetone and isopropyl alcohol (IPA) addition. The tested biodieselhols consisted of pure diesel oil (D100) with 1-3 vol.% pure acetone (denoted as A), 1-70 vol.% waste-edible-oil-biodiesel (denoted as W), and 1 vol.% pure isopropyl alcohol (the stabilizer, denoted as P). The results show that in comparison to W1D99, W3D97, W5D95, W10D90, and W20D80, the use of biodieselhols achieved additional reduction of PM and particulate organic carbon (OC) emission, and such reduction increased as the addition percentage of pure acetone increased. Regardless of the percentages of added waste-edible-oil-biodiesel, acetone, and isopropyl alcohol, the use of biodieselhol in place of D100 could reduce the emissions of Total-PAHs (by 6.13-42.5% (average = 24.1%)) and Total-BaPeq (by 16.6-74.8% (average = 53.2%)) from the diesel engine generator. Accordingly, the W/D blended fuels (W<20 vol.%) containing acetone (1-3 vol.%) and isopropyl alcohol (1 vol.%) are a potential alternative fuel for diesel engine generators because they substantially reduce emissions of PM, particulate OC, Total-PAHs, and Total-BaPeq. PMID:23911918

Tsai, Jen-Hsiung; Chen, Shui-Jen; Huang, Kuo-Lin; Lin, Wen-Yinn; Lee, Wen-Jhy; Lin, Chih-Chung; Hsieh, Lien-Te; Chiu, Juei-Yu; Kuo, Wen-Chien

2014-01-01

71

Resonances of Kalb-Ramond field on symmetric and asymmetric thick branes  

NASA Astrophysics Data System (ADS)

Motivated by the previous work on the fermion resonances on symmetric thick branes [Phys. Rev. D 80, 065020 (2009)], we extend the idea to the Kalb-Ramond (KR) resonances on the asymmetric thick branes. The localization and resonance of the KR field on symmetric and asymmetric thick branes are investigated in detail. In order to analyze the effect of scalar and KR field interaction on the spectrum of KR field Kaluza-Klein modes, we introduce a coupling between the background kink field and KR field, and find that there exist some resonant modes. In the case of a symmetric brane, we seek the resonances by using both the relative probability and transfer matrix methods, and show the consistency of results with the two methods. While for the asymmetric case, it is found that we can only apply one of the above two methods, i.e., the transfer matrix method, which reveals that the asymmetry reduces the number of the resonant modes of the KR field.

Du, Yun-Zhi; Zhao, Li; Zhong, Yi; Fu, Chun-E.; Guo, Heng

2013-07-01

72

Capture of Trojans by Jumping Jupiter  

NASA Astrophysics Data System (ADS)

Jupiter Trojans are thought to be survivors of a much larger population of planetesimals that existed in the planetary region when planets formed. They can provide important constraints on the mass and properties of the planetesimal disk, and its dispersal during planet migration. Here, we tested a possibility that the Trojans were captured during the early dynamical instability among the outer planets (aka the Nice model), when the semimajor axis of Jupiter was changing as a result of scattering encounters with an ice giant. The capture occurs in this model when Jupiter's orbit and its Lagrange points become radially displaced in a scattering event and fall into a region populated by planetesimals (that previously evolved from their natal transplanetary disk to ~5 AU during the instability). Our numerical simulations of the new capture model, hereafter jump capture, satisfactorily reproduce the orbital distribution of the Trojans and their total mass. The jump capture is potentially capable of explaining the observed asymmetry in the number of leading and trailing Trojans. We find that the capture probability is (6-8) 10-7 for each particle in the original transplanetary disk, implying that the disk contained (3-4) 107 planetesimals with absolute magnitude H < 9 (corresponding to diameter D = 80 km for a 7% albedo). The disk mass inferred from this work, M disk ~ 14-28 M Earth, is consistent with the mass deduced from recent dynamical simulations of the planetary instability.

Nesvorn, David; Vokrouhlick, David; Morbidelli, Alessandro

2013-05-01

73

CAPTURE OF TROJANS BY JUMPING JUPITER  

NASA Astrophysics Data System (ADS)

Jupiter Trojans are thought to be survivors of a much larger population of planetesimals that existed in the planetary region when planets formed. They can provide important constraints on the mass and properties of the planetesimal disk, and its dispersal during planet migration. Here, we tested a possibility that the Trojans were captured during the early dynamical instability among the outer planets (the Nice model), when the semimajor axis of Jupiter was changing as a result of scattering encounters with an ice giant. The capture occurs in this model when Jupiter's orbit and its Lagrange points become radially displaced in a scattering event and fall into a region populated by planetesimals (that previously evolved from their natal transplanetary disk to ~5 AU during the instability). Our numerical simulations of the new capture model, hereafter jump capture, satisfactorily reproduce the orbital distribution of the Trojans and their total mass. The jump capture is potentially capable of explaining the observed asymmetry in the number of leading and trailing Trojans. We find that the capture probability is (6-8) 10^-7 for each particle in the original transplanetary disk, implying that the disk contained (3-4) 10^7 planetesimals with absolute magnitude H < 9 (corresponding to diameter D = 80 km for a 7% albedo). The disk mass inferred from this work, M_disk ~ 14-28 M_Earth, is consistent with the mass deduced from recent dynamical simulations of the planetary instability.

Nesvorny, David; Vokrouhlicky, D.; Morbidelli, A.

2013-10-01

74

Electric vehicle dynamic-stress-test cycling performance of lithium-ion cells  

SciTech Connect

Dynamic Stress tests (DST) of. small lithium-ion cells have demonstrated that the systems delivers high energy (65 Wh/kg, 4.3 hours runtime) with reasonable cycle-life (375--480 cycles) under the full USABC mid-term dynamic-stress-test conditions (150 W/kg). At lower DoD substantially higher cycle life was observed (2800 cycles at 44% DoD, 1.9 hours runtime). Both the DoD and charging voltage V{sub c} (4.1V < V{sub c} < 4.2 V) affect the delivered energy and cell life in an interacting manner. At high DoD (>80%), a lower V{sub c} is prefered because it maximize cycle life with a small penalty in energy. At intermediate DoD (40--80%) a higher V{sub c} is preferred. Long-term tests are needed to determine the DST cycle life at very low DoD (<40%). The high power pulse of the DST test limits the delivered cell energy and life. If a high energy density load leveling, technology is developed (e.g. flywheels or double layer capacitors) the delivered energy and cycle life could be substantially increased.

Mayer, S.T.

1994-05-01

75

GYGD pore motifs in neighbouring potassium channel subunits interact to determine ion selectivity  

PubMed Central

Cells maintain a negative resting membrane potential through the constitutive activity of background K+ channels. A novel multigene family of such K+ channels has recently been identified. A unique characteristic of these K+ channels is the presence of two homologous, subunit-like domains, each containing a pore-forming region. Sequence co-variations in the GYGD signature motifs of the two pore regions suggested an interaction between neighbouring pore domains. Mutations of the GYGD motif in the rat drk1 (Kv2.1) K+ channel showed that the tyrosine (Y) position was important for K+ selectivity and single channel conductance, whereas the aspartate (D) position was a critical determinant of open state stability. Tandem constructs engineered to mimic the GYGx-GxGD pattern seen in two-domain K+ channels delineated a co-operative intersubunit interaction between the Y and D positions, which determined ion selectivity, conductance and gating. In the bacterial KcsA K+ channel crystal structure, the equivalent aspartate residue (D80) does not directly interact with permeating K+ ions. However, the data presented here show that the D position is able to fine-tune ion selectivity through a functional interaction with the Y position in the neighbouring subunit. These data indicate a physiological basis for the extensive sequence variation seen in the GYGD motifs of two-domain K+ channels. It is suggested that a cell can precisely regulate its resting membrane potential by selectively expressing a complement of two-domain K+ channels. PMID:11136855

Chapman, Mark L; Krovetz, Howard S; VanDongen, Antonius M J

2001-01-01

76

Joint scalar transported PDF modeling of nonpiloted turbulent diffusion flames  

SciTech Connect

A transported joint probability density function (JPDF) approach closed at the joint scalar level has been applied to investigate two nonpiloted CH{sub 4}/H{sub 2}/N{sub 2} turbulent (Re 15200 and 22800) jet diffusion flames. The flames have been studied experimentally at the Deutsches Zentrum fur Luft- und Raumfahrt (DLR) and at Sandia National Laboratories and are well characterized experimentally through extensive velocity and scalar measurements. The flames offer the opportunity of computational investigations of turbulence-chemistry interactions in CH{sub 4}/H{sub 2} flames in the absence of both partial premixing with air and with a smaller stoichiometric mixture fraction (Z{sub st}=0.167) than in the corresponding piloted Sandia flames. The two flames also offer different levels of local extinction. Comparatively few theoretical studies have been performed of these flames and the present work provides an assessment of the ability of the transported PDF approach to reproduce their detailed thermochemical structure. The chemical closure is obtained through a systematically reduced C/H/O/N mechanism featuring 16 independent, 4 dependent, and 28 steady-state scalars. The velocity field is computed using the second moment closure of Speziale et al. and molecular mixing is modeled using the modified Curl's model. It is shown that velocity and scalar fields are generally well reproduced for 10=D=<80 though uncertainties in boundary conditions have an impact closer to the burner exit.

Lindstedt, R.P.; Ozarovsky, H.C. [Thermofluids Division, Department of Mechanical Engineering, Imperial College of Science, Technology and Medicine, Exhibition Road, London SW7 2AZ (United Kingdom)

2005-12-01

77

Testing Modified Gravity with Gravitational-Wave Observations from Space  

NASA Astrophysics Data System (ADS)

The inspiral of stellar compact objects into massive black holes sitting at galactic centers, usually known as extreme-mass-ratio inspirals (EMRIs), is one of the most important sources of gravitational radiation for the future Laser Interferometer Space Antenna (LISA), an ESA-NASA mission. It is expected that LISA will determine the physical parameters of these sources with a high precision. These precise measurements open the possibility of making robust tests of the existence of black holes, of their geometry, and even of the gravitational interaction. In relation to this, intermediate-mass-ratio inspirals (IMRIs) are also of interest to advance ground-based gravitational-wave observatories. In this talk, we discuss how modifications to the gravitational interaction can affect the signals emitted by EMRIs and the detectability of these modifications by LISA. To that end, we present results from an study of a particular modification of General Relativity (GR): Chern-Simons modified gravity, a theory that emerges in different quantum gravitational approaches and where spinning black holes have a geometry different from the Kerr geometry predicted by GR. References: C. F. Sopuerta and N. Yunes "Extreme and Intermediate-Mass Ratio Inspirals in Dynamical Chern-Simons Modified Gravity" Physical Review D80, 064006 (2009). e-Print: arXiv:0904.4501 [gr-qc

Sopuerta, Carlos F.; Yunes, Nicolas

78

Collaborative Assessment and Management of Suicidality in an Inpatient Setting: Results of a Pilot Study  

PubMed Central

Patients hospitalized for psychiatric reasons exhibit significantly elevated risk of suicide, yet the research literature contains very few outcome studies of interventions designed for suicidal inpatients. This pilot study examined the inpatient feasibility and effectiveness of The Collaborative Assessment and Management of Suicidality (CAMS), a structured evidence-based method for risk assessment and treatment planning (Jobes, 2006). The study used an open-trial, case-focused design to assess an inpatient adaptation of CAMS, spread over a period averaging 51 days. The intervention was provided via individual therapy to a convenience sample of 20 patients (16 females and four males, average age 36.9) who were hospitalized with recent histories of suicidal ideation and behavior. Results showed statistically and clinically significant reductions in depression, hopelessness, suicide cognitions, and suicidal ideation, as well as improvement on factors considered drivers of suicidality. Treatment effect sizes were in the large range (Cohens d > .80) across several outcome measures, including suicidal ideation. Although these findings must be considered preliminary due to the lack of a randomized control group, they merit attention from clinicians working with patients at risk for suicide. This study also supports the feasibility of implementing a structured, suicide-specific intervention for at-risk patients in inpatient settings. PMID:22369081

Ellis, Thomas E.; Green, Kelly L.; Allen, Jon G.; Jobes, David A.; Nadorff, Michael R.

2013-01-01

79

Scanning SQUID Microscopy of Local Superconductivity in Inhomogeneous Combinatorial Ceramics.  

PubMed

Although combinatorial solid-state chemistry promises to be an efficient way to search for new superconducting compounds, the problem of determining which compositions are strongly diamagnetic in a mixed-phase sample is challenging. By means of reactions in a system of randomly mixed starting components (Ca, Sr, Ba, La, Y, Pb, Bi, Tl, and Cu oxides), samples were produced that showed an onset of diamagnetic response above 115?K in bulk measurements. Imaging of this diamagnetic response in ceramic samples by scanning SQUID microscopy (SSM) revealed local superconducting areas with sizes down to as small as the spatial resolution of a few micrometers. In addition, locally formed superconducting matter was extracted from mixed-phase samples by magnetic separation. The analysis of single grains (d<80??m) by X-ray diffraction, elemental analysis, and bulk SQUID measurements allowed Tl2 Ca3 Ba2 Cu4 O12 , TlCaBaSrCu2 O7-? , BaPb0.5 Bi0.25 Tl0.25 O3-? , TlBa2 Ca2 Cu3 O9 , Tl2 Ba2 CaCu2 O8 , and YBa2 Cu3 O7 phases to be identified. SSM, in combination with other diagnostic techniques, is therefore shown to be a useful instrument to analyze inhomogeneous reaction products in the solid-state chemistry of materials showing magnetic properties. PMID:25303177

Iranmanesh, Mitra; Stir, Manuela; Kirtley, John R; Hulliger, Jrg

2014-11-24

80

Structural changes of the KcsA potassium channel upon application of the electrode potential studied by surface-enhanced IR absorption spectroscopy  

NASA Astrophysics Data System (ADS)

Structural changes of the KcsA potassium channel fixed on gold electrode surface in the upright orientation were studied by surface-enhanced IR absorption spectroscopy (SEIRAS). Measurements were performed at neutral pH, where the activation gate is kept closed. Band intensities were enhanced for the asymmetric (1565 cm-1) and symmetric (1405 cm-1) OCO-carboxylate groups at negative electrode potentials in the K+ solution, but not in the Na+ solution. Even for the reverse-oriented channel, the enhanced OCO-carboxylate band was evident at negative potential. When TBA was loaded in the central cavity, the K+-specific OCO band was not elicited. These results indicate that the negative electrode potential renders the local K+ concentration accumulated at the vicinity of the electrode surface, and the KcsA channel bathed in high K+ changes conformation of the selectivity filter from the collapsed to the open, and OCO-carboxylate groups (D80 and E71) in the back of the filter were rearranged.

Yamakata, Akira; Shimizu, Hirofumi; Osawa, Masatoshi; Oiki, Shigetoshi

2013-06-01

81

Wide-field Corrector for a Gregory Telescope  

E-print Network

A form of prime focus corrector for the Gregory system is proposed that provides the sub-arcsecond field of view up to 3 degrees in diameter for the spectral range 0.35-0.90 microns. The corrector includes five lenses made of same glass (fused silica is preferable). The distinctive feature of the corrector consists in dissimilar use of the central and edge zones of a front lens disposed in the exit pupil of a two-mirror system. As an example, the f/1.9 telescope is considered with the 6.5-m aperture and the total length 8.8~m. Its primary and secondary mirrors are pure ellipsoids close to concave paraboloid and concave sphere, respectively. In the basic configuration, all surfaces of the corrector are spherical. The diameter of a star image D_{80} varies from 0''.25 on the optical axis up to 0''.50 at the edge of the 2.3-deg field. Only slightly worse images shows spherical corrector for the 2.4-deg field of view. The fraction of vignetted rays grows on 1.7% from the center of field to its edges. Aspherizatio...

Terebizh, V Y

2006-01-01

82

Wide-field Corrector for a Gregory Telescope  

E-print Network

A form of prime focus corrector for the Gregory system is proposed that provides the sub-arcsecond field of view up to 3 degrees in diameter for the spectral range 0.35-0.90 microns. The corrector includes five lenses made of same glass (fused silica is preferable). The distinctive feature of the corrector consists in dissimilar use of the central and edge zones of a front lens disposed in the exit pupil of a two-mirror system. As an example, the f/1.9 telescope is considered with the 6.5-m aperture and the total length 8.8~m. Its primary and secondary mirrors are pure ellipsoids close to concave paraboloid and concave sphere, respectively. In the basic configuration, all surfaces of the corrector are spherical. The diameter of a star image D_{80} varies from 0''.25 on the optical axis up to 0''.50 at the edge of the 2.3-deg field. Only slightly worse images shows spherical corrector for the 2.4-deg field of view. The fraction of vignetted rays grows on 1.7% from the center of field to its edges. Aspherization of some lens surfaces allows to reach sub-arcsecond images in the field of 3.0 in diameter.

V. Yu. Terebizh

2006-05-15

83

Plasma flow in a high-power thruster with anode layer  

NASA Astrophysics Data System (ADS)

Among Hall thruster technologies, the thruster with anode layer (TAL) seems to have much wider technical capabilities. Various aspects of the quasi-neutral plasma flow in a high power thruster with anode layer are studied. A model of plasma flow in the TAL channel is developed based on a 2D hydrodynamic approach. In particular, plasma -wall interactions are studied in detail. Formation of the sheath near the acceleration channel wall and sheath expansion in the acceleration channel are calculated. Both single- and two-stage TALs are investigated. It is found that the high voltage sheath expands significantly and the quasi-neutral plasma region is confined in the middle of the channel. For instance, in the case of a 3 kV discharge voltage, the sheath thickness is about 1 cm, which is a significant portion of the channel width. An effect of sheath expansion on the acceleration region is studied using a quasi 1D simplified model. It is found that sheath expansion leads to decrease of the acceleration region length. A particular example of this thruster, high voltage TAL (D-80) is also studied. The model predicts a non-monotonic behavior of thruster efficiency with discharge voltage. The location of maximum efficiency is found to be in agreement with experiment.

Keidar, Michael; Boyd, Iain

2004-11-01

84

Rigidification of the autolysis loop enhances Na[superscript +] binding to thrombin  

SciTech Connect

Binding of Na{sup +} to thrombin ensures high activity toward physiological substrates and optimizes the procoagulant and prothrombotic roles of the enzyme in vivo. Under physiological conditions of pH and temperature, the binding affinity of Na{sup +} is weak due to large heat capacity and enthalpy changes associated with binding, and the K{sub d} = 80 mM ensures only 64% saturation of the site at the concentration of Na{sup +} in the blood (140 mM). Residues controlling Na{sup +} binding and activation have been identified. Yet, attempts to improve the interaction of Na{sup +} with thrombin and possibly increase catalytic activity under physiological conditions have so far been unsuccessful. Here we report how replacement of the flexible autolysis loop of human thrombin with the homologous rigid domain of the murine enzyme results in a drastic (up to 10-fold) increase in Na{sup +} affinity and a significant improvement in the catalytic activity of the enzyme. Rigidification of the autolysis loop abolishes the heat capacity change associated with Na{sup +} binding observed in the wild-type and also increases the stability of thrombin. These findings have general relevance to protein engineering studies of clotting proteases and trypsin-like enzymes.

Pozzi, Nicola; Chen, Raymond; Chen, Zhiwei; Bah, Alaji; Di Cera, Enrico (St. Louis-MED)

2011-09-20

85

Characterization of Giardia duodenalis infections in dogs in Trinidad and Tobago.  

PubMed

To our knowledge, the zoonotic potential of Giardia duodenalis has not been assessed in companion animals in Trinidad and Tobago. This report details the first attempt to evaluate the potential zoonotic risk of G. duodenalis in dogs and identify assemblages of G. duodenalis found in dog populations on both islands. Fecal samples were collected from free-roaming dogs and dogs at the Trinidad and Tobago Society for the Prevention of Cruelty to Animals from October 2010 to June 2011. A total of 168 samples were collected of which 104 samples were analyzed for the presence of G. duodenalis by PCR amplification of the ssu-rRNA gene with subsequent assemblage-typing. A subset of samples was also analyzed by ELISA. Twenty-six samples were positive for G. duodenalis by PCR for an overall prevalence of 25%. Four samples were identified as assemblage C (15.4%), 21 as assemblage D (80.8%), and one as assemblage E (3.8%). Puppies were four-times more likely to be infected with G. duodenalis than adult dogs (OR 4.61, 95% CI 1.73-12.2). There was a significant agreement between ELISA and PCR in the detection of the protozoa (?=0.67). We infer from our results that while the prevalence of G. duodenalis is relatively high in Trinidad and Tobago, the zoonotic risk of infection in humans is low since neither assemblage A nor B was identified in the study population. PMID:23465438

Mark-Carew, Miguella P; Adesiyun, Abiodun A; Basu, Asoke; Georges, Karla A; Pierre, Theresa; Tilitz, Sophie; Wade, Susan E; Mohammed, Hussni O

2013-09-01

86

Accurate and efficient waveforms for compact binaries on eccentric orbits  

NASA Astrophysics Data System (ADS)

Compact binaries that emit gravitational waves in the sensitivity band of ground-based detectors can have non-negligible eccentricities just prior to merger, depending on the formation scenario. We develop a purely analytic, frequency-domain model for gravitational waves emitted by compact binaries on orbits with small eccentricity, which reduces to the quasicircular post-Newtonian approximant TaylorF2 at zero eccentricity and to the postcircular approximation of Yunes et al. [Phys. Rev. D 80, 084001 (2009)] at small eccentricity. Our model uses a spectral approximation to the (post-Newtonian) Kepler problem to model the orbital phase as a function of frequency, accounting for eccentricity effects up to O(e8) at each post-Newtonian order. Our approach accurately reproduces an alternative time-domain eccentric waveform model for e?[0,0.4] and binaries with total mass ?12M?. As an application, we evaluate the signal amplitude that eccentric binaries produce in different networks of existing and forthcoming gravitational waves detectors. Assuming a population of eccentric systems containing black holes and neutron stars that is uniformly distributed in comoving volume, we estimate that second-generation detectors like Advanced LIGO could detect approximately 0.1-10 events per year out to redshift z0.2, while an array of Einstein Telescope detectors could detect hundreds of events per year to redshift z2.3.

Huerta, E. A.; Kumar, Prayush; McWilliams, Sean T.; O'Shaughnessy, Richard; Yunes, Nicols

2014-10-01

87

Opioid binding site in EL-4 thymoma cell line  

SciTech Connect

Using EL-4 thymoma cell-line we found a binding site similar to the k opioid receptor of the nervous system. The Scatchard analysis of the binding of (/sup 3/H) bremazocine indicated a single site with a K/sub D/ = 60 +/- 17 nM and Bmax = 2.7 +/- 0.8 pmols/10/sup 6/ cells. To characterize this binding site, competition studies were performed using selective compounds for the various opioid receptors. The k agonist U-50,488H was the most potent displacer of (/sup 3/H) bremazocine with an IC/sub 50/ value = 0.57..mu..M. The two steroisomers levorphanol and dextrorphan showed the same affinity for this site. While morphine, (D-Pen/sup 2/, D-Pen/sup 5/) enkephalin and ..beta..-endorphin failed to displace, except at very high concentrations, codeine demonstrated a IC/sub 50/ = 60..mu..M, that was similar to naloxone. 32 references, 3 figures, 2 tables.

Fiorica, E.; Spector, S.

1988-01-01

88

Altered stress-induced cortisol levels in goats exposed to polychlorinated biphenyls (PCB 126 and PCB 153) during fetal and postnatal development.  

PubMed

Short-term stress exposure is associated with activation of the hypothalamic-pituitary-adrenal (HPA) axis and a consequent rise in blood glucocorticoids and catecholamines, from the adrenal cortex and medulla, respectively. The HPA axis is a potential target for some persistent organic pollutants, among which polychlorinated biphenyls (PCB) were found to be modulators of the mammalian endocrine system. PCB are distributed globally in the environment, in food chains, and are transferred to the fetuses of pregnant animals and via mother's milk to suckling offspring. In the present study it was postulated that intrauterine and lactational exposure to either of two single congeners of PCB (PCB 153 and PCB 126, respectively) might affect basal cortisol concentrations, and also the cortisol response to short-term stress in adulthood. Thus, pregnant goats were orally exposed to one of these PCB congeners from d 60 of gestation until delivery, and their offspring studied. Low-dose exposure to PCB 153 and PCB 126 resulted in significantly lower mean basal cortisol concentrations in goat offspring during certain periods of pubertal development and their first breeding season. Male goat kids exposed to either PCB congener showed a greater and more prolonged rise in plasma cortisol levels than controls when animals were subjected to mild stress at 9 mo of age using frequent blood sampling. Neither the basal maternal cortisol plasma level nor goat kid adrenal masses were affected by PCB exposure. PMID:19184731

Zimmer, Karin E; Gutleb, Arno C; Lyche, Jan L; Dahl, Ellen; Oskam, Irma C; Krogenaes, Anette; Skaare, Janneche Utne; Ropstad, Erik

2009-01-01

89

The human Werner syndrome protein stimulates repair of oxidative DNA base damage by the DNA glycosylase NEIL1.  

PubMed

The mammalian DNA glycosylase, NEIL1, specific for repair of oxidatively damaged bases in the genome via the base excision repair pathway, is activated by reactive oxygen species and prevents toxicity due to radiation. We show here that the Werner syndrome protein (WRN), a member of the RecQ family of DNA helicases, associates with NEIL1 in the early damage-sensing step of base excision repair. WRN stimulates NEIL1 in excision of oxidative lesions from bubble DNA substrates. The binary interaction between NEIL1 and WRN (K(D) = 60 nM) involves C-terminal residues 288-349 of NEIL1 and the RecQ C-terminal (RQC) region of WRN, and is independent of the helicase activity WRN. Exposure to oxidative stress enhances the NEIL-WRN association concomitant with their strong nuclear co-localization. WRN-depleted cells accumulate some prototypical oxidized bases (e.g. 8-oxoguanine, FapyG, and FapyA) indicating a physiological function of WRN in oxidative damage repair in mammalian genomes. Interestingly, WRN deficiency does not have an additive effect on in vivo damage accumulation in NEIL1 knockdown cells suggesting that WRN participates in the same repair pathway as NEIL1. PMID:17611195

Das, Aditi; Boldogh, Istvan; Lee, Jae Wan; Harrigan, Jeanine A; Hegde, Muralidhar L; Piotrowski, Jason; de Souza Pinto, Nadja; Ramos, William; Greenberg, Marc M; Hazra, Tapas K; Mitra, Sankar; Bohr, Vilhelm A

2007-09-01

90

Modulation of the biochemical composition of amniotic and allantoic fluids as a control mechanism of feline foetal development.  

PubMed

Amniotic fluid exerts a protective function and is an essential component for foetal development and maturation during pregnancy. However, little is known about the exact physiological functions of foetal fluids in this process as well as their biochemical composition in cats. In the present study, the biochemical composition of amniotic and allantoic fluids and maternal serum in pregnant queens was compared after performing an ovariohysterectomy. Fifteen queens were included in the study and distributed in four different groups, D(30), D(40), D(50) and D(60), according to their gestational age. Foetal fluids showed thoroughly greater concentrations of dissociate and total bilirubin, bile acids and gamma-glutamyl transferase than those of maternal serum, whereas albumin, total protein, alanine-transferase, creatine-kinase, amylase, lipase, triglycerides, cholesterol, HDL-cholesterol, and LDL-cholesterol were significantly lower, as compared to maternal serum. Other parameters like alkaline phosphatase, uric acid, creatinine, and electrolytes showed significant differences at specific stages of pregnancy, when compared to maternal serum. Lactate and cortisol significantly increased at the end of the pregnancy in foetal fluids, when compared with maternal serum. No significant differences between foetal fluids and maternal serum were observed for aspartate aminotransferase, lactate dehydrogenase, urea, phosphorus and glucose. According to our results, foetal fluids composition is not a result of simple filtration from maternal blood, the fetus being an active element involved in the production of the same and reflecting organ development and maturation. PMID:22465420

Fresno, L; Rodriguez-Gil, J E; Rigau, T; Pastor, J; Rivera del Alamo, M M

2012-06-01

91

Monte Carlo simulations and radiation dosimetry measurements of peripherally applied HDR {sup 192}Ir breast brachytherapy D-shaped applicators  

SciTech Connect

Conformal dose coverage for accelerated partial breast irradiation or radiotherapy boost can be obtained with AccuBoost registered D-shaped brachytherapy applicators using a flattened surface positioned near the patient. Three D-shaped applicators (D45/D53/D60) were dosimetrically characterized using Monte Carlo methods (MCNP5), air ionization chambers (Farmer and Markus), and radiochromic film (GafChromic EBT) in polystyrene and ICRU 44 breast tissue. HDR {sup 192}Ir source dwell times were either constant or optimized to improve skin dose uniformity. Scatter dose decreased as depth decreased. 10 mm beyond the applicator aperture, dose reductions of 90% and 51% were observed at depths of 0 and 30 mm, respectively. Similarly, planar dose uniformity improved as depth decreased and was also due to scatter and applicator geometry. Dose uniformity inside the applicator aperture was approximately 11% and 15% for all three applicators at the skin and 30 mm deep, respectively. Depth dose measurements in polystyrene using ion chamber and radiochromic film agreed with Monte Carlo results within 2%. Discrepancies between film and Monte Carlo dose profiles at 30 mm depth were within 1%.

Yang Yun; Rivard, Mark J. [Department of Biomedical Engineering and Biotechnology, University of Massachusetts Lowell, Massachusetts 01854 (United States); Department of Radiation Oncology, Tufts University School of Medicine, Boston, Massachusetts 02111 (United States)

2009-03-15

92

A Search for Colorful Characters Among the Jupiter Greeks and Trojans  

NASA Astrophysics Data System (ADS)

As more and more space craft rendezvous with asteroids, it has become increasingly apparent that asteroids do not always present a single heterogeneous surface to observers. Global variation in color and albedo can be caused by impact events or non-uniform composition which can, in turn, provide details about the recent collisional history and the formation mechanisms of these objects. Here we look to determine the level of surface color uniformity for a sample of Jupiter Greek and Trojan asteroids through multi-filter light curve observations. For this study high cadence, partial light curves were taken of several large (D > 60km) Trojan and Greek asteroids in simultaneous V and I broadband photometric filters using the CTIO 0.9m, the CTIO 1.0m, and the Lowell 42in telescopes. For these observations color variation of 0.03 magnitudes should be observable using relative photometry. The Greeks and Trojans themselves, as largely primordial populations and a key test parameters for the Nice Model, are very fascinating groups for studying Solar System formation. Information on the collisional history of those populations through a search for color variation in their largest members could prove vital for a better understanding of their evolution and origins.

Chatelain, Joseph; Pewett, T.; Henry, T.; French, L.; Winters, J.

2013-10-01

93

The effect of pressure on the surface plasmon absorption spectra of colloidal gold and silver particles  

SciTech Connect

The first measurements of the effect of pressure on the peak position ({omega}{sub sp}) and line width (fwhm) of the surface plasmon absorption in several Au and Ag hydrosols have been recorded up to 10 kbar. Red shifts of the plasmon peak with increasing pressure are observed for relatively large metal particles prepared by the citrate procedure (Au, {anti d} = 265 {angstrom}; Ag, {anti d} = 230 {angstrom}). The shift for silver is over twice that of gold ({minus}420 cm{sup {minus}1} vs {minus} 200 cm{sup {minus}1}). These red shifts are interpreted in terms of pressure-induced volume changes within the context of a free-electron model. In contrast, particles prepared by the Faraday method (Au, {anti d} = 54 {angstrom}; Ag, d{anti d} = 60 {angstrom}) show initial blue shifts with pressure, with the magnitude again larger for silver. Upon aging (as well as upon heating in the case of Au), the Au and Ag Faraday sols exhibit an increase in their average particle size and degree of aggregation. Correspondingly, the pressure response of their plasmon absorption approaches that of the citrate sols.

Coffer, J.L.; Shapley, J.R.; Drickamer, H.G. (Univ. of Illinois, Urbana (USA))

1990-05-09

94

Assessment of Natural Radioactivity Levels of Cements and Cement Composites in the Slovak Republic  

PubMed Central

The radionuclide activities of 226Ra, 232Th and 40K and radiological parameters (radium equivalent activity, gamma and alpha indices, the absorbed gamma dose rate and external and internal hazard indices) of cements and cement composites commonly used in the Slovak Republic have been studied in this paper. The cement samples of 8 types of cements from Slovak cement plants and five types of composites made from cement type CEM I were analyzed in the experiment. The radionuclide activities in the cements ranged from 8.5819.1 Bqkg?1, 9.7826.3 Bqkg?1 and 156.5489.4 Bqkg?1 for 226Ra, 232Th and 40K, respectively. The radiological parameters in cement samples were calculated as follows: mean radium equivalent activity Raeq = 67.87 Bqkg?1, gamma index I? = 0.256, alpha index I? = 0.067, the absorbed gamma dose rate D = 60.76 nGyh?1, external hazard index Hex = 0.182 and internal hazard index Hin was 0.218. The radionuclide activity in composites ranged from 6.8410.8 Bqkg?1 for 226Ra, 13.120.5 Bqkg?1 for 232Th and 250.4494.4 Bqkg?1 for 40K. The calculated radiological parameters of cements were lower than calculated radiological parameters of cement composites. PMID:24351739

Estokova, Adriana; Palascakova, Lenka

2013-01-01

95

Effects of age and dietary soybean oil level on eggshell quality, bone strength and blood biochemistry in laying hens.  

PubMed

Abstract 1. The objective of the study was to investigate the differences in eggshell quality, bone quality and serum bone biochemistry markers associated with changes in age and dietary soybean oil levels in laying hens. 2. A total of 54, 19-week-old Hy-Line Brown laying hens were housed in 18 battery cages (3 birds/cage) and randomly divided into three diet treatments for 90 d: control-fat (CF, 1.9% soybean oil), moderate-fat (MF, 7% soybean oil) and high-fat (HF, 10% soybean oil). 3. The hens' body weights (BW), egg production, egg weights, eggshell thickness and femoral diameter were higher at d 90 than at d 60 or d 30. Meanwhile, feed intake, relative bone weights, all bone strength parameters and serum Ca were lower at d 90 or 60 than at d 30. 4. Compared to the CF hens, the feed intake, BW, abdominal fat pad weights and serum alkaline phosphatase activity were elevated in MF or HF hens. The eggshell thickness, relative femoral and tibial weight, femoral stiffness, femoral modulus, tibial mixed force and serum calcium and phosphorus levels were lower in MF or HF hens than CF hens. 5. These findings suggest that bone loss in caged hens starts from an early stage of the laying period, and dietary oil (particularly with diets over 10% soybean oil) has harmful effects on eggshell quality, bone strength and bone mineralisation from an early stage of the laying period. PMID:25109942

Jiang, S; Cui, L Y; Hou, J F; Shi, C; Ke, X; Yang, L C; Ma, X P

2014-10-01

96

Assessment of natural radioactivity levels of cements and cement composites in the Slovak Republic.  

PubMed

The radionuclide activities of 226Ra, 232Th and 40K and radiological parameters (radium equivalent activity, gamma and alpha indices, the absorbed gamma dose rate and external and internal hazard indices) of cements and cement composites commonly used in the Slovak Republic have been studied in this paper. The cement samples of 8 types of cements from Slovak cement plants and five types of composites made from cement type CEM I were analyzed in the experiment. The radionuclide activities in the cements ranged from 8.58-19.1 Bqkg(-1), 9.78-26.3 Bqkg(-1) and 156.5-489.4 Bqkg(-1) for 226Ra, 232Th and 40K, respectively. The radiological parameters in cement samples were calculated as follows: mean radium equivalent activity Ra(eq) = 67.87 Bqkg(-1), gamma index I? = 0.256, alpha index I? = 0.067, the absorbed gamma dose rate D = 60.76 nGyh(-1), external hazard index H(ex) = 0.182 and internal hazard index H(in) was 0.218. The radionuclide activity in composites ranged from 6.84-10.8 Bqkg(-1) for 226Ra, 13.1-20.5 Bqkg(-1) for 232Th and 250.4-494.4 Bqkg(-1) for 40K. The calculated radiological parameters of cements were lower than calculated radiological parameters of cement composites. PMID:24351739

Etokov, Adriana; Pala?kov, Lenka

2013-12-01

97

A 10-kW series resonant converter design, transistor characterization, and base-drive optimization  

NASA Technical Reports Server (NTRS)

The development, components, and performance of a transistor-based 10 kW series resonant converter for use in resonant circuits in space applications is described. The transistors serve to switch on the converter current, which has a half-sinusoid waveform when the transistor is in saturation. The goal of the program was to handle an input-output voltage range of 230-270 Vdc, an output voltage range of 200-500 Vdc, and a current limit range of 0-20 A. Testing procedures for the D60T and D7ST transistors are outlined and base drive waveforms are presented. The total device dissipation was minimized and found to be independent of the regenerative feedback ratio at lower current levels. Dissipation was set at within 10% and rise times were found to be acceptable. The finished unit displayed a 91% efficiency at full power levels of 500 V and 20 A and 93.7% at 500 V and 10 A.

Robson, R. R.; Hancock, D. J.

1982-01-01

98

Cassava Stillage Treatment by Thermophilic Anaerobic Continuously Stirred Tank Reactor (CSTR)  

NASA Astrophysics Data System (ADS)

This paper assesses the performance of a thermophilic anaerobic Continuously Stirred Tank Reactor (CSTR) in the treatment of cassava stillage under various organic loading rates (OLRs) without suspended solids (SS) separation. The reactor was seeded with mesophilic anaerobic granular sludge, and the OLR increased by increments to 13.80 kg COD/m3/d (HRT 5d) over 80 days. Total COD removal efficiency remained stable at 90%, with biogas production at 18 L/d (60% methane). Increase in the OLR to 19.30 kg COD/m3/d (HRT 3d), however, led to a decrease in TCOD removal efficiency to 79% due to accumulation of suspended solids and incomplete degradation after shortened retention time. Reactor performance subsequently increased after OLR reduction. Alkalinity, VFA and pH levels were not significantly affected by OLR variation, indicating that no additional alkaline or pH adjustment is required. More than half of the SS in the cassava stillage could be digested in the process when HRT was 5 days, which demonstrated the suitability of anaerobic treatment of cassava stillage without SS separation.

Luo, Gang; Xie, Li; Zou, Zhonghai; Zhou, Qi

2010-11-01

99

Effect of Acacia karroo Supplementation on Growth, Ultimate pH, Colour and Cooking Losses of Meat from Indigenous Xhosa Lop-eared Goats  

PubMed Central

The objective of the study was to determine the effect of Acacia karroo supplementation on growth, ultimate pH, colour and cooking losses of meat from indigenous Xhosa lop-eared goats. Eighteen castrated 4-month-old kids were used in the study until slaughter. The kids were subdivided in two treatment groups A. karroo supplemented (AK) and non-supplemented (NS). The supplemented goats were given 200 g per head per d of fresh A. karroo leaves. The kids were slaughtered on d 60 and sample cuttings for meat quality assessment were taken from the Longistimus dorsi muscle. The supplemented kids had higher (p<0.05) growth rates than the non-supplemented ones. The meat from the A. karroo supplemented goats had lower (p<0.05) ultimate pH and cooking loss than the meat from the non-supplemented goats. Acacia karroo supplemented goats produced higher (p<0.05) b* (yellowness) value, but supplementation had no significant effect on L* (lightness) and a* (redness) of the meat. Therefore, A. karroo supplementation improved growth performance and the quality of meat from goats. PMID:25049715

Ngambu, S.; Muchenje, V.; Marume, U.

2013-01-01

100

Brief Motivational Feedback and Cognitive Behavioral Interventions for Prevention of Disordered Gambling: A Randomized Clinical Trial  

PubMed Central

Aims The purpose of the current study was to evaluate feasibility and efficacy of two promising approaches to indicated prevention of disordered gambling in a college population. Design Randomized controlled trial with assignment to a Personalized Feedback Intervention (PFI), Cognitive-Behavioral Intervention (CBI), or Assessment-Only Control (AOC). PFI was individually delivered in a single session and included feedback regarding gambling behavior, norms, consequences, and risk-reduction tips, delivered in a motivational interviewing style. CBI was delivered in small groups over 4-6 sessions and included functional analysis, brief cognitive correction, as well as identification of and alternatives for responding to gambling triggers. Setting College campus. Participants At-risk or probable pathological gamblers (N = 147; 65.3% male; group assignment: PFI, n = 52; CBI, n = 44; AOC, n = 51). Measurements Self-reported gambling quantity, frequency, consequences, psychopathology, normative perceptions, and beliefs. Findings Relative to control, results at 6-month follow-up indicated reductions in both interventions for gambling consequences (PFI d = .48; CBI d = .39) and DSM-IV criteria (PFI d=.60; CBI d=.48), reductions in frequency for PFI (d = .48). CBI was associated with reduced illusions of control, whereas PFI was associated with reduced perceptions of gambling frequency norms. Reductions in perceived gambling frequency norms mediated effects of PFI on gambling frequency. Conclusions A single-session Personalized Feedback Intervention and a multi-session Cognitive-Behavioral Intervention may be helpful in reducing disordered gambling in US college students. PMID:22188239

Larimer, Mary E.; Neighbors, Clayton; Lostutter, Ty W.; Whiteside, Ursula; Cronce, Jessica M.; Kaysen, Debra; Walker, Denise D.

2012-01-01

101

Changing the omega-6 to omega-3 fatty acid ratio in sow diets alters serum, colostrum, and milk fatty acid profiles, but has minimal impact on reproductive performance.  

PubMed

This experiment tested the hypothesis that reducing the omega-6 (n-6) to omega-3 (n-3) fatty acid (FA) ratio in sow diets will improve performance, characterized by increased litter size, decreased preweaning mortality, and improved growth performance. Second, we determined if the FA profile in sow and piglet blood, colostrum, and milk are altered when sows are fed diets with varied n-6:n-3 ratios and if the dietary FA ratio impacts circulating concentrations of IgG, IgA, eicosapentaenoic (EPA), or docosahexaenoic (DHA) acid. Sows (n = 150) were assigned to 1 of 5 treatments (each divided into gestation and lactation diets) on d 80 of gestation. Period 1 (P1) is defined as d 80 of gestation to weaning and Period 2 (P2) refers to the subsequent breeding to weaning. Diets were wheat and barley based (5% crude fat) and treatments consisted of a control (tallow), 3 diets with plant oil-based n-6:n-3 ratios (9:1P, 5:1P, and 1:1P), and a 5:1 fish oil diet (5:1F). Litter size was unaffected by treatment during P1 and P2 (P > 0.10). In P1, birth weight was unaffected by diet (P > 0.10); however, weaning weight (P = 0.019) and ADG from birth to weaning (P = 0.011) were greatest for piglets born to 9:1P and 5:1P sows. During P2, 5:1F sows consumed 10% less feed during lactation (P = 0.036), tended to have reduced piglet birth weights (P = 0.052), and piglet weaning weight was reduced by 0.8 kg (P = 0.040) relative to the other diets. Colostrum and piglet serum IgA and IgG concentrations were unaffected by diet (P > 0.10). Serum n-3 FA were greatest in sows (P < 0.01) consuming 1:1P and 5:1F diets and in their offspring (P = 0.014). Serum ?-linolenic acid (ALA) was greatest in 1:1P sows and EPA and DHA were greatest in 5:1F sows (P < 0.01). In pre-suckle piglet serum, ALA did not differ among treatment groups (P > 0.10). Relative to piglets of sows consuming the control diet, EPA was 2.5-fold greater in the 1:1P group and 4-fold greater in 5:1F group (P < 0.01) before suckling. In post-suckle samples, ALA was greatest in piglets from the 1:1P sows (P < 0.01) and EPA and DHA were greatest in piglets from the 5:1F sows (P < 0.01). Feeding diets with plant-based n-6:n-3 ratios of 5:1 or 1:1 did not impact performance relative to a control group but improved the conversion of ALA into EPA and increased the transfer of n-3 to piglets through milk. When a fish-based 5:1 ratio diet was fed, pre-weaning mortality was increased, and piglet birth and weaning weights decreased. PMID:25403193

Eastwood, L; Leterme, P; Beaulieu, A D

2014-12-01

102

Dietary protein restriction of pregnant rats in the F0 generation induces altered methylation of hepatic gene promoters in the adult male offspring in the F1 and F2 generations  

PubMed Central

Epidemiological studies and experimental models show that maternal nutritional constraint during pregnancy alters the metabolic phenotype of the offspring and that this can be passed to subsequent generations. In the rat, induction of an altered metabolic phenotype in the liver of the F1 generation by feeding a protein-restricted diet (PRD) during pregnancy involves altered methylation of specific gene promoters. We therefore investigated whether altered methylation of peroxisomal proliferator-activated receptor (PPAR?) and glucocorticoid receptor (GR) promoters is passed to the F2 generation. Females rats (F0) were fed a reference diet (RD, 18% protein) or PRD (9% protein) throughout gestation, and AIN76A during lactation. F1 offspring were weaned onto AIN76A. F1 females were mated and fed AIN76A throughout pregnancy and lactation. F1 and F2 males were killed on postnatal d 80. Hepatic PPAR? and GR promoter methylation was significantly (P<0.05) lower in the PRD group in the F1 (PPAR? 8%; GR 10%) and F2 (PPAR? 11%; GR 8%) generations. There were trends (P<0.1) towards higher expression of PPAR?, GR, acyl-CoA oxidase and phosphoenolpyruvate carboxykinase (PEPCK) in the F1 and F2 males, although this was only significant for PEPCK. These data show for the first time that altered methylation of gene promoters induced in the F1 generation by maternal protein-restriction during pregnancy is transmitted to the F2 generation. This may represent a mechanism for the transmission of induced phenotypes between generations. PMID:17313703

Burdge, Graham C.; Slater-Jefferies, Jo; Torrens, Christopher; Phillips, Emma S.; Hanson, Mark A.; Lillycrop, Karen A.

2008-01-01

103

A Semi-Automated Technique Determining the Liver Standardized Uptake Value Reference for Tumor Delineation in FDG PET-CT  

PubMed Central

Background 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)-computed tomography (CT) has been an essential modality in oncology. We propose a semi-automated algorithm to objectively determine liver standardized uptake value (SUV), which is used as a threshold for tumor delineation. Methods A large spherical volume of interest (VOI) was placed manually to roughly enclose the right lobe (RL) of the liver. For each voxel in this VOI, a coefficient of variation of voxel values (CVv) was calculated for neighboring voxels within a radius of d/2. The voxel with the minimum CVv was then selected, where a 30-mm spherical VOI was placed at that voxel in accordance with PERCIST criteria. Two nuclear medicine physicians independently defined 30-mm VOIs manually on 124 studies in 62 patients to generate the standard values, against which the results from the new method were compared. Results The semi-automated method was successful in determining the liver SUV that was consistent between the two physicians in all the studies (d?=?80 mm). The liver SUV threshold (mean +3 SD within 30-mm VOI) determined by the new semi-automated method (3.120.61) was not statistically different from those determined by the manual method (Physician-1: 3.140.58, Physician-2: 3.150.58). The semi-automated method produced tumor volumes that were not statistically different from those by experts' manual operation. Furthermore, the volume change in the two sequential studies had no statistical difference between semi-automated and manual methods. Conclusions Our semi-automated method could define the liver SUV robustly as the threshold value used for tumor volume measurements according to PERCIST. The method could avoid possible subjective bias of manual liver VOI placement and is thus expected to improve clinical performance of volume-based parameters for prediction of cancer treatment response. PMID:25162396

Hirata, Kenji; Kobayashi, Kentaro; Wong, Koon-Pong; Manabe, Osamu; Surmak, Andrew; Tamaki, Nagara; Huang, Sung-Cheng

2014-01-01

104

Characteristics of Na(+)-Ca2+ exchange in frog skeletal muscle.  

PubMed Central

1. Fluxes studies were carried out to investigate the Na(+)-dependent outward movement of Ca2+ in intact frog sartorius muscle from Leptodactylus ocellatus, a preparation for which published data on the subject are sparse. 2. Under normal resting conditions the Na(+)-Ca2+ exchange was not readily detectable. 3. When muscles were exposed to 4 mM caffeine, the rate of fractional loss of Ca2+ (kCa,o) increased by about 50%. Most of this increase exhibits characteristics typical of the Na(+)-Ca2+ antiport working in the forward mode found in other cells. 4. The increase in kCa,o promoted by caffeine was decreased by: (a) 72% in the absence of external Na+ (Nao+); (b) 73% in Na(+)-loaded muscles ([Na+]i = 98 mM); (c) 70% when fibres were depolarized to -27 mV ([K+]o = 50 mM); and (d) 80% in the presence of 5 mM amiloride. 5. Ni2+ (5 mM), an inhibitor of the Na(+)-Ca2+ exchanger current, unexpectedly increased the caffeine-promoted rise in kCa,o. This effect of Ni2+ was associated with a concomitant caffeine-stimulated Ni2+ influx. In the absence of caffeine Ni2+ did not affect kCa,o. 6. It was concluded that: (a) under resting conditions the sarcolemmal Ca2+ pump suffices to handle the cytosolic calcium concentration ([Ca2+]i); (b) Na(+)-Ca2+ activity becomes apparent when [Ca2+]i is substantially increased by caffeine-induced Ca2+ release from the sarcoplasmic reticulum; and (c) the blocking effect of Ni2+ on the current generated by a Na(+)-Ca2+ exchange with a coupling ratio > 2 might actually represent a shift of the antiport mode toward an electroneutral 1 Ni(2+)-1Ca2+ exchange. PMID:7473224

Hoya, A; Venosa, R A

1995-01-01

105

Experimental study on the flow regimes and pressure gradients of air-oil-water three-phase flow in horizontal pipes.  

PubMed

An experimental investigation has been carried out to study the flow regimes and pressure gradients of air-oil-water three-phase flows in 2.25 ID horizontal pipe at different flow conditions. The effects of water cuts, liquid and gas velocities on flow patterns and pressure gradients have been studied. The experiments have been conducted at 20 C using low viscosity Safrasol D80 oil, tap water and air. Superficial water and oil velocities were varied from 0.3 m/s to 3 m/s and air velocity varied from 0.29 m/s to 52.5 m/s to cover wide range of flow patterns. The experiments were performed for 10% to 90% water cuts. The flow patterns were observed and recorded using high speed video camera while the pressure drops were measured using pressure transducers and U-tube manometers. The flow patterns show strong dependence on water fraction, gas velocities, and liquid velocities. The observed flow patterns are stratified (smooth and wavy), elongated bubble, slug, dispersed bubble, and annular flow patterns. The pressure gradients have been found to increase with the increase in gas flow rates. Also, for a given superficial gas velocity, the pressure gradients increased with the increase in the superficial liquid velocity. The pressure gradient first increases and then decreases with increasing water cut. In general, phase inversion was observed with increase in the water cut. The experimental results have been compared with the existing unified Model and a good agreement has been noticed. PMID:24523645

Al-Hadhrami, Luai M; Shaahid, S M; Tunde, Lukman O; Al-Sarkhi, A

2014-01-01

106

Meat Science and Muscle Biology Symposium: developmental programming in cattle: consequences for growth, efficiency, carcass, muscle, and beef quality characteristics.  

PubMed

This paper reviews results of studies on effects of fetal programming and maternal nutrition during pregnancy on growth, efficiency, carcass, muscle, and meat quality characteristics of cattle. It includes results from our Australian Beef Cooperative Research Centre studies on factors such as chronic severe nutritional restriction from approximately d 80 of pregnancy to parturition and/or throughout lactation used to create early-life growth differences in the offspring of cows within pasture-based systems and the effect of these treatments on production characteristics to 30 mo of age. Fetal programming and related maternal effects are most pronounced and explain substantial amounts of variation for growth-related production characteristics such as BW, feed intake, carcass weight, muscle weights, meat yield, and fat and bone weights at any given age but are less evident when assessed at the same BW and carcass weight. Some effects of maternal and early-life factors in our studies were evident for efficiency traits but fewer affected beef quality characteristics at 30 mo of age, explaining only small amounts of variation in these traits. It is difficult to uncouple maternal nutritional effects specific to prenatal life from those that carry over to the postnatal period until weaning, particularly the effects of maternal nutrition during pregnancy on subsequent lactational performance. Hence, experimental design considerations for studying fetal programming effects on offspring during later life are discussed in relation to minimizing or removing prenatal and postnatal confounding effects. The relative contribution of fetal programming to the profitability of beef production systems is also briefly discussed. In this regard, the importance of health and survival of cows and calves, the capacity of cows to rebreed in a timely manner, and the efficiency with which feed and other resources are used cannot be overemphasized in relation to economics, welfare, and the environment. PMID:23230118

Robinson, D L; Cafe, L M; Greenwood, P L

2013-03-01

107

Genitourinary Toxicity After High-Dose-Rate (HDR) Brachytherapy Combined With Hypofractionated External Beam Radiotherapy for Localized Prostate Cancer: An Analysis to Determine the Correlation Between Dose-Volume Histogram Parameters in HDR Brachytherapy and Severity of Toxicity  

SciTech Connect

Purpose: To evaluate the severity of genitourinary (GU) toxicity in high-dose-rate (HDR) brachytherapy combined with hypofractionated external beam radiotherapy (EBRT) for prostate cancer and to explore factors that might affect the severity of GU toxicity. Methods and Materials: A total of 100 Japanese men with prostate cancer underwent {sup 192}Ir HDR brachytherapy combined with hypofractionated EBRT. Mean (SD) dose to 90% of the planning target volume was 6.3 (0.7) Gy per fraction of HDR. After 5 fractions of HDR treatment, EBRT with 10 fractions of 3 Gy was administrated. The urethral volume receiving 1-15 Gy per fraction in HDR brachytherapy (V1-V15) and the dose to at least 5-100% of urethral volume in HDR brachytherapy (D5-D100) were compared between patients with Grade 3 toxicity and those with Grade 0-2 toxicity. Prostate volume, patient age, and International Prostate Symptom Score were also compared between the two groups. Results: Of the 100 patients, 6 displayed Grade 3 acute GU toxicity, and 12 displayed Grade 3 late GU toxicity. Regarding acute GU toxicity, values of V1, V2, V3, and V4 were significantly higher in patients with Grade 3 toxicity than in those with Grade 0-2 toxicity. Regarding late GU toxicity, values of D70, D80, V12, and V13 were significantly higher in patients with Grade 3 toxicity than in those with Grade 0-2 toxicity. Conclusions: The severity of GU toxicity in HDR brachytherapy combined with hypofractionated EBRT for prostate cancer was relatively high. The volume of prostatic urethra was associated with grade of acute GU toxicity, and urethral dose was associated with grade of late GU toxicity.

Ishiyama, Hiromichi [Department of Radiology, Kitasato University School of Medicine, Kitasato, Sagamihara, Kanagawa (Japan)], E-mail: hishiyam@kitasato-u.ac.jp; Kitano, Masashi [Department of Radiology, Kitasato University School of Medicine, Kitasato, Sagamihara, Kanagawa (Japan); Satoh, Takefumi [Department of Urology, Kitasato University School of Medicine, Kitasato, Sagamihara, Kanagawa (Japan); Kotani, Shouko [Department of Radiology, Kitasato University School of Medicine, Kitasato, Sagamihara, Kanagawa (Japan); Uemae, Mineko [Division of Radiation Oncology, Kitasato University Hospital, Kitasato, Sagamihara, Kanagawa (Japan); Matsumoto, Kazumasa; Okusa, Hiroshi; Tabata, Ken-ichi; Baba, Shiro [Department of Urology, Kitasato University School of Medicine, Kitasato, Sagamihara, Kanagawa (Japan); Hayakawa, Kazushige [Department of Radiology, Kitasato University School of Medicine, Kitasato, Sagamihara, Kanagawa (Japan)

2009-09-01

108

MCPI: a sub-minute Monte Carlo dose calculation engine for prostate implants.  

PubMed

An accelerated Monte Carlo code [Monte Carlo dose calculation for prostate implant (MCPI)] is developed for dose calculation in prostate brachytherapy. MCPI physically simulates a set of radioactive seeds with arbitrary positions and orientations, merged in a three-dimensional (3D) heterogeneous phantom representing the prostate and surrounding tissue. MCPI uses a phase space data source-model to account for seed self-absorption and seed anisotropy. A "hybrid geometry" model (full 3D seed geometry merged in 3D mesh of voxels) is used for rigorous treatment of the interseed attenuation and tissue heterogeneity effects. MCPI is benchmarked against the MCNP5 code for idealized and real implants, for 103Pd and 125I seeds. MCPI calculates the dose distribution (2-mm voxel mesh) of a 103Pd implant (83 seeds) with 2% average statistical uncertainty in 59 s using a single Pentium 4 PC (2.4 GHz). MCPI is more than 10(3) and 10(4) times faster than MCNP5 for prostate dose calculations using 2- and 1-mm voxels, respectively. To illustrate its usefulness, MCPI is used to quantify the dosimetric effects of interseed attenuation, tissue composition, and tissue calcifications. Ignoring the interseed attenuation effect or slightly varying the prostate tissue composition may lead to 6% decreases of D100, the dose delivered to 100% of the prostate. The presence of calcifications, covering 1%-5% of the prostate volume, decreases D80, D90, and D100 by up to 32%, 37%, and 58%, respectively. In conclusion, sub-minute dose calculations, taking into account all dosimetric effects, are now possible for more accurate dose planning and dose assessment in prostate brachytherapy. PMID:16475768

Chibani, Omar; Williamson, Jeffrey F

2005-12-01

109

Experimental Study on the Flow Regimes and Pressure Gradients of Air-Oil-Water Three-Phase Flow in Horizontal Pipes  

PubMed Central

An experimental investigation has been carried out to study the flow regimes and pressure gradients of air-oil-water three-phase flows in 2.25 ID horizontal pipe at different flow conditions. The effects of water cuts, liquid and gas velocities on flow patterns and pressure gradients have been studied. The experiments have been conducted at 20C using low viscosity Safrasol D80 oil, tap water and air. Superficial water and oil velocities were varied from 0.3?m/s to 3?m/s and air velocity varied from 0.29?m/s to 52.5?m/s to cover wide range of flow patterns. The experiments were performed for 10% to 90% water cuts. The flow patterns were observed and recorded using high speed video camera while the pressure drops were measured using pressure transducers and U-tube manometers. The flow patterns show strong dependence on water fraction, gas velocities, and liquid velocities. The observed flow patterns are stratified (smooth and wavy), elongated bubble, slug, dispersed bubble, and annular flow patterns. The pressure gradients have been found to increase with the increase in gas flow rates. Also, for a given superficial gas velocity, the pressure gradients increased with the increase in the superficial liquid velocity. The pressure gradient first increases and then decreases with increasing water cut. In general, phase inversion was observed with increase in the water cut. The experimental results have been compared with the existing unified Model and a good agreement has been noticed. PMID:24523645

Al-Hadhrami, Luai M.; Shaahid, S. M.; Tunde, Lukman O.; Al-Sarkhi, A.

2014-01-01

110

Novel de novo SPOCK1 mutation in a proband with developmental delay, microcephaly and agenesis of corpus callosum.  

PubMed

Whole exome sequencing made it possible to identify novel de novo mutations in genes that might be linked to human syndromes (genotype first analysis). We describe a female patient with a novel de novo SPOCK1 variant, which has not been previously been associated with a human phenotype. Her features include intellectual disability with dyspraxia, dysarthria, partial agenesis of corpus callosum, prenatal-onset microcephaly and atrial septal defect with aberrant subclavian artery. Previous genetic, cytogenomic and metabolic studies were unrevealing. At age 13 years, exome sequencing on the patient and her parents revealed a de novo novel missense mutation in SPOCK1 (coding for Testican-1) on chromosome 5q31: c.239A>T (p.D80V). This mutation affects a highly evolutionarily conserved area of the gene, replacing a polar aspartic acid with hydrophobic nonpolar valine, and changing the chemical properties of the protein product, likely representing a pathogenic variant. Previous microdeletions of 5q31 including SPOCK1 have suggested genes on 5q31 as candidates for intellectual disability. No mutations or variants in other genes potentially linked to her phenotype were identified. Testicans are proteoglycans belonging to the BM-40/SPARC/osteonectin family of extracellular calcium-binding proteins. Testican-1 is encoded by the SPOCK1 gene, and mouse models have been shown it to be strongly expressed in the brain and to be involved in neurogenesis. We hypothesize that because this gene function is critical for neurogenesis, mutations could potentially lead to a phenotype with developmental delay and microcephaly. PMID:24583203

Dhamija, Radhika; Graham, John M; Smaoui, Nizar; Thorland, Erik; Kirmani, Salman

2014-03-01

111

Relic gravitational waves in light of the 7-year Wilkinson Microwave Anisotropy Probe data and improved prospects for the Planck mission  

SciTech Connect

The new release of data from Wilkinson Microwave Anisotropy Probe improves the observational status of relic gravitational waves. The 7-year results enhance the indications of relic gravitational waves in the existing data and change to the better the prospects of confident detection of relic gravitational waves by the currently operating Planck satellite. We apply to WMAP7 data the same methods of analysis that we used earlier [W. Zhao, D. Baskaran, and L. P. Grishchuk, Phys. Rev. D 80, 083005 (2009)] with WMAP5 data. We also revised by the same methods our previous analysis of WMAP3 data. It follows from the examination of consecutive WMAP data releases that the maximum likelihood value of the quadrupole ratio R, which characterizes the amount of relic gravitational waves, increases up to R=0.264, and the interval separating this value from the point R=0 (the hypothesis of no gravitational waves) increases up to a 2{sigma} level. The primordial spectra of density perturbations and gravitational waves remain blue in the relevant interval of wavelengths, but the spectral indices increase up to n{sub s}=1.111 and n{sub t}=0.111. Assuming that the maximum likelihood estimates of the perturbation parameters that we found from WMAP7 data are the true values of the parameters, we find that the signal-to-noise ratio S/N for the detection of relic gravitational waves by the Planck experiment increases up to S/N=4.04, even under pessimistic assumptions with regard to residual foreground contamination and instrumental noises. We comment on theoretical frameworks that, in the case of success, will be accepted or decisively rejected by the Planck observations.

Zhao, W. [School of Physics and Astronomy, Cardiff University, Cardiff, CF24 3AA (United Kingdom); Wales Institute of Mathematical and Computational Sciences, Swansea, SA2 8PP (United Kingdom); Department of Physics, Zhejiang University of Technology, Hangzhou, 310014 (China); Baskaran, D. [School of Physics and Astronomy, Cardiff University, Cardiff, CF24 3AA (United Kingdom); Wales Institute of Mathematical and Computational Sciences, Swansea, SA2 8PP (United Kingdom); Grishchuk, L. P. [School of Physics and Astronomy, Cardiff University, Cardiff, CF24 3AA (United Kingdom); Sternberg Astronomical Institute, Moscow State University, Moscow, 119899 (Russian Federation)

2010-08-15

112

Lipid-soluble vitamins A, D, and E in HIV-infected pregnant women in Tanzania  

PubMed Central

Background/Objectives There is limited published research examining lipid-soluble vitamins in human immunodeficiency virus (HIV)-infected pregnant women, particularly in resource-limited settings. Subjects/Methods This is an observational analysis of 1078 HIV-infected pregnant women enrolled in a trial of vitamin supplementation in Tanzania. Baseline data on sociodemographic and anthropometric characteristics, clinical signs and symptoms, and laboratory parameters were used to identify correlates of low plasma vitamin A (<0.7 ?mol/l), vitamin D (<80 nmol/l) and vitamin E (<9.7 ?mol/l) status. Binomial regression was used to estimate risk ratios and 95% confidence intervals. Results Approximately 35, 39 and 51% of the women had low levels of vitamins A, D and E, respectively. Severe anemia (hemoglobin <85 g/l; P<0.01), plasma vitamin E (P=0.02), selenium (P=0.01) and vitamin D (P=0.02) concentrations were significant correlates of low vitamin A status in multivariate models. Erythrocyte Sedimentation Rate (ESR) was independently related to low vitamin A status in a nonlinear manner (P=0.01). The correlates of low vitamin D status were CD8 cell count (P=0.01), high ESR (ESR >81 mm/h; P<0.01), gestational age at enrollment (nonlinear; P=0.03) and plasma vitamins A (P=0.02) and E (P=0.01). For low vitamin E status, the correlates were money spent on food per household per day (P<0.01), plasma vitamin A concentration (nonlinear; P<0.01) and a gestational age <16 weeks at enrollment (P<0.01). Conclusions Low concentrations of lipid-soluble vitamins are widely prevalent among HIV-infected women in Tanzania and are correlated with other nutritional insufficiencies. Identifying HIV-infected persons at greater risk of poor nutritional status and infections may help inform design and implementation of appropriate interventions. PMID:20517330

Mehta, S; Spiegelman, D; Aboud, S; Giovannucci, EL; Msamanga, GI; Hertzmark, E; Mugusi, FM; Hunter, DJ; Fawzi, WW

2010-01-01

113

Experimental and numerical investigations on PDE performance augmentation by means of an ejector  

NASA Astrophysics Data System (ADS)

To improve the performance of pulse detonation engines, a 48 cm long cylindrical combustion chamber of 5cm internal diameter (i.d.) is fitted with an ejector of constant section. The role of the ejector is (i) to provide partial confinement of the detonation products escaping from the chamber and (ii) to suck in fresh air and then to increase the mass ejected compared to the ejection of burned gases alone. The combustion chamber is fully filled with a stoichiometric ethylene/oxygen mixture at ambient conditions. Three parameters of the ejector are varied: the i.d. D, the length L, and the position d relative to the thrust wall of the combustion chamber. For various configurations, the specific impulse ( I sp) is determined in single shot experiments. The maximum operating frequency ( f max) and the maximum thrust are then deduced. I sp is measured by means of the ballistic pendulum method, and f max is derived from the pressure signal recorded on the combustion chamber thrust wall. The addition of an ejector increases the specific impulse up to 60% in the best configuration tested, from 164s without ejector to 260s with ejector. The specific impulse can be represented by a single curve using suitable dimensionless parameters. The thrust results for the main ejector studied ( D = 80mm) indicate an optimal ( L, d) configuration that provides a 28% thrust gain. For the same ejector, f max remains constant and equal to the frequency obtained without ejector in a large range of ( L, d) values, before decreasing. Two-dimensional unsteady numerical computations agree reasonably with the experiments, slightly overestimating the experimental values. The results indicate that 80% of the I sp gain comes from the action of the expanding detonation products on the annular end surface of the combustion chamber, governed by the tube wall thickness.

Canteins, G.; Franzetti, F.; Zoc?o?ska, E.; Khasainov, B. A.; Zitoun, R.; Desbordes, D.

2006-06-01

114

Self-organization of local magnetoplasma structures in the upper layers of the solar convection zone  

SciTech Connect

Self-organization and evolution of magnetoplasma structures in the upper layers of the solar convection zone are discussed as a process of diffuse aggregation of magnetic flux tubes. Equations describing the tube motion under the action of magnetic interaction forces, hydrodynamic forces, and random forces are written explicitly. The process of aggregation of magnetic flux tubes into magnetic flux clusters of different shapes and dimensions is simulated numerically. The obtained structures are compared with the observed morphological types of sunspot groups. The quantitative comparison with the observational data was performed by comparing the fractal dimensions of the photospheric magnetic structures observed in solar active regions with those of structures obtained in the numerical experiment. The model has the following free parameters: the numbers of magnetic flux tubes with opposite polarities on the considered area element (Nn and Ns), the average radius of the cross section of the magnetic flux tube (a), its effective length (l), the twist factor of the tube field (k), and the absolute value of the average velocity of chaotic tube displacements (d). Variations in these parameters in physically reasonable limits leads to the formation of structures (tube clusters of different morphological types) having different fractal dimensions. Using the NOAA 10488 active region, which appeared and developed into a complicated configuration near the central meridian, as an example, it is shown that good quantitative agreement between the fractal dimensions is achieved at the following parameters of the model: Nn = Ns = 250 50; a = 150 50 km; l ? 5000 km, and d = 80 10 m/s. These results do not contradict the observational data and theoretical estimates obtained in the framework of the Parker spaghetti model and provide new information on the physical processes resulting in the origin and evolution of local magnetic plasma structures in the near-photospheric layers of the solar convection zone.

Chumak, O. V., E-mail: chuo@yandex.ru [Moscow State University, Sternberg Astronomical Institute (Russian Federation)

2013-08-15

115

Requirement of the flagellar protein export apparatus component FliO for optimal expression of flagellar genes in Helicobacter pylori.  

PubMed

Flagellar biogenesis in Helicobacter pylori involves the coordinated expression of flagellar genes with assembly of the flagellum. The H. pylori flagellar genes are organized into three regulons based on the sigma factor needed for their transcription (RpoD [?(80)], RpoN [?(54)], or FliA [?(28)]). Transcription of RpoN-dependent genes is activated by a two-component system consisting of the sensor kinase FlgS and the response regulator FlgR. While the cellular cues sensed by the FlgS/FlgR two-component system remain to be elucidated, previous studies revealed that disrupting certain components of the flagellar export apparatus inhibited transcription of the RpoN regulon. FliO is the least conserved of the membrane-bound components of the export apparatus and has not been annotated for any of the H. pylori genomes sequenced to date. A PSI-BLAST analysis identified a potential H. pylori FliO protein which membrane topology algorithms predict to possess a large N-terminal periplasmic domain that is absent from FliO of Escherichia coli and Salmonella, the paradigms for flagellar structure/function studies. FliO was necessary for flagellar biogenesis as well as wild-type levels of motility and transcription of RpoN-dependent and FliA-dependent flagellar genes in H. pylori strain B128. FliO also appears to be required for wild-type levels of the export apparatus protein FlhA in the membrane. Interestingly, the periplasmic and cytoplasmic domains were somewhat dispensable for flagellar gene regulation and assembly, suggesting that these domains have relatively minor roles in flagellar synthesis. PMID:24837287

Tsang, Jennifer; Hoover, Timothy R

2014-08-01

116

Evolving the [Myoglobin, Cytochrome b5] Complex from Dynamic Toward Simple Docking: Charging the Electron-Transfer Reactive Patch  

PubMed Central

We describe photo-initiated electron transfer (ET) from a suite of Zn-substituted myoglobin (1Mb) variants to cytochrome b5 (b5). An electrostatic interface redesign strategy has led to the introduction of positive charges in the vicinity of the heme edge through D/E ? K charge-reversal mutation combinations at `hotspot' residues (D44, D60, E85), augmented by the elimination of negative charges from Mb or b5 by neutralization of heme propionates. These variations create an unprecedentedly large range in the product of the ET partners' total charges: ?5 < ?qMbqb5 < 40. The binding affinity (Ka) increases a thousand-fold as ?qMbqb5 increases through this range, and exhibits a surprisingly simple, exponential dependence on ?qMbqb5. This is explained in terms of electrostatic interactions between a `charged reactive patch' (crp) on each partner's surface, defined as a compact region around the heme edge that (i) contains the total protein charge of each variant, and (ii) encompasses a major fraction of the `reactive region' (Rr) comprising surface atoms with large matrix elements for electron tunneling to the heme. As ?qMbqb5 increases, the complex undergoes a transition from fast to slow exchange dynamics on the triplet ET timescale, with a correlated progression in the rate constants for intracomplex (ket) and bimolecular (k2) ET. This progression is analyzed by integrating the crp and Rr descriptions of ET into the textbook steady-state treatment of reversible binding between partners that undergo intracomplex ET, and found to encompass the full range of behaviors predicted by the model. The generality of this approach is demonstrated by applying it to the extensive body of data for the ET complex between the photosynthetic reaction center and cytochrome c2. Deviations from this model also are discussed. PMID:23067206

Trana, Ethan N.; Nocek, Judith M.; Knutson, Amanda K.; Hoffman, Brian M.

2012-01-01

117

Incidence of jaw lesions and activity and gene expression of hepatic P4501A enzymes in mink (Mustela vison) exposed to dietary 2,3,7,8-tetrachlorodibenzo-p-dioxin, 2,3,7,8-tetrachlorodibenzofuran, and 2,3,4,7,8-pentachlorodibenzofuran.  

PubMed

This study assessed the effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 2,3,4,7,8-pentachlorodibenzofuran (PeCDF), and 2,3,7,8 tetrachlorodibenzofuran (TCDF) on the incidence of jaw lesions and on hepatic cytochrome P4501A (CYP1A) endpoints in mink (Mustela vison). Adult female mink were assigned randomly to one of 13 dietary treatments (control and four increasing doses of TCDD, PeCDF, or TCDF) and provided spiked feed for approximately 150 d (60 d prior to breeding through weaning of offspring at 42 d post-parturition). Offspring were maintained on their respective diets for an additional 150 d. Activity of hepatic CYP1A enzymes in adult and juvenile mink exposed to TCDD, PeCDF, or TCDD was generally greater compared with controls, but changes in other CYP1A endpoints were less consistent. Histopathology of the mandible and maxilla of juvenile mink suggested a dose-related increase in the incidence of jaw lesions. The dietary effective doses (ED) for jaw lesions in 50% of the population (ED50) were estimated to be 6.6, 14, and 149 ng/kg body weight (bw)/d for TCDD, PeCDF, and TCDF, respectively. The relative potencies of PeCDF and TCDF compared with TCDD based on ED10, ED20, and ED50 values ranged from 0.5 to 1.9 and 0.04 to 0.09, respectively. These values are within an order of magnitude of the World Health Organization toxic equivalency factor (TEF(WHO)) values of 0.3 and 0.1 for PeCDF and TCDF, respectively. PMID:22865772

Bursian, Steven J; Moore, Jeremy; Newsted, John L; Link, Jane E; Fitzgerald, Scott D; Bello, Nora; Bhat, Virunya S; Kay, Denise; Zhang, Xiaowei; Wiseman, Steve; Budinsky, Robert A; Giesy, John P; Zwiernik, Matthew J

2012-11-01

118

Nail psoriasis as a severity indicator: results from the PsoReal study  

PubMed Central

Background: Although nail psoriasis affects a substantial proportion of psoriasis patients and causes significant psychologic distress, few epidemiologic data characterizing patients with nail involvement are available. The aim of this research was to elucidate differences between patients with nail psoriasis and those without any nail involvement, taking quality indicators of health care from the patients perspective into account. Methods: In total, 2449 patient members of the Deutscher Psoriasis Bund, the largest patient organization for psoriasis in Germany, were interviewed in this nationwide, noninterventional, cross-sectional study. Patients with nail psoriasis were compared with patients without any nail involvement with regard to gender, age, disease duration, affected body surface area, health-related quality of life (Dermatology Life Quality Index [DLQI] ED-5D), patient-defined treatment benefit, amount of inpatient treatments, disease duration, and numbers of work days lost. Results: Data from 2449 patients with psoriasis were analyzed. Overall, 44.8% (1078) of patients were female, mean age was 57.0 11.7 years, and 72.8% had nail involvement and showed higher values for affected body surface area than those without nail involvement (8.3% versus 5.6%, respectively; P < 0.004). Health-related quality of life was significantly lower in patients with nail psoriasis (DLQI 7.2 versus 5.3; ED-5D 60.1 versus 67.3), who had more days off work (9.8 versus 3.3). Conclusion: Nail involvement is an important symptom of psoriasis and is associated with greater disease severity and quality of life impairment. Accordingly, management of psoriasis should include a special focus on nail involvement. PMID:22915964

Radtke, Marc A; Langenbruch, Anna K; Schafer, Ines; Herberger, Katharina; Reich, Kristian; Augustin, Matthias

2011-01-01

119

Phosphorus sorption capacities and physicochemical properties of nine substrate materials for constructed wetland.  

PubMed

Constructed wetland (CW) is a promising technique for removal of pollutants from wastewater and agricultural runoff. The performance of a CW to remove pollutants, however, hinges on the use of suitable substrate materials. This study examined the physicochemical properties and phosphorus (P) sorption capacities of nine different CW substrate materials using both batch experiments and the Freundlich as well as the Langmuir isotherm. The nine substrate materials used in this study were turf, topsoil, gravel, midsized sand (MSS), blast furnace slag (BFS), coal burn slag (CBS), blast furnace artificial slag (BFAS), coal burn artificial slag (CBAS), and midsized artificial sand (MSAS). Experimental data showed that sorption of P increased with initial solution P concentrations for all nine substrate materials. The maximum P sorption capacity of the substrate materials estimated by Langmuir isotherm was in the following order: turf (4243 mg/kg substrate) > BFAS (2116 mg/kg substrate) > BFS (1598 mg/kg substrate) > CBS (1449 mg/kg substrate) > top soil (1396 mg/kg substrate) > CBAS (1194 mg/kg substrate) > MSAS (519 mg/kg substrate) > gravel (494 mg/kg substrate) > MSS (403 mg/kg substrate). The specific gravity of eight substrate materials (except gravel) had very significant negative correlations with the P sorption, whereas the particle diameter of D(60) and uniformity coefficient (K(60)) had positive correlations with the P sorption. The cation exchange capacity, organic matter, available ferrous, and exchangeable aluminum of the eight substrate materials also had very significant positive correlations with the P sorption, while the pH of the substrate materials showed a very significant negative correlation with the P sorption. Our study further suggests that turf and CBAS are the two relatively ideal substrate materials suitable for removal of P from a CW system. PMID:18175159

Cui, Lihua; Zhu, Xizhen; Ma, Mei; Ouyang, Ying; Dong, Mei; Zhu, Wenling; Luo, Shiming

2008-08-01

120

Prematurely Elevating Estradiol in Early Baboon Pregnancy Suppresses Uterine Artery Remodeling and Expression of Extravillous Placental Vascular Endothelial Growth Factor and ?1?1 and ?5?1 Integrins  

PubMed Central

We previously showed that advancing the increase in estradiol levels from the second to the first third of baboon pregnancy suppressed placental extravillous trophoblast (EVT) invasion and remodeling of the uterine spiral arteries. Cell culture studies show that vascular endothelial cell growth factor (VEGF) plays a central role in regulating EVT migration and remodeling of the uterine spiral arteries by increasing the expression/action of certain integrins that control extracellular matrix remodeling. To test the hypothesis that the estradiol-induced reduction in vessel remodeling in baboons is associated with an alteration in VEGF and integrin expression, extravillous placental VEGF and integrin expression was determined on d 60 of gestation (term is 184 d) in baboons in which uterine artery transformation was suppressed by maternal estradiol administration on d 2559. EVT uterine spiral artery invasion was 5-fold lower (P < 0.01), and VEGF protein expression, quantified by in situ proximity ligation assay, was 50% lower (P < 0.05) in the placenta anchoring villi of estradiol-treated than in untreated baboons. ?1?1 and ?5?1 mRNA levels in cells isolated by laser capture microdissection from the anchoring villi and cytotrophoblastic shell of estradiol-treated baboons were over 2-fold (P < 0.01) and 40% (P < 0.05) lower, respectively, than in untreated animals. In contrast, placental extravillous ?v?3 mRNA expression was unaltered by estradiol treatment. In summary, extravillous placental expression of VEGF and ?1?1 and ?5?1 integrins was decreased in a cell- and integrin-specific manner in baboons in which EVT invasion and remodeling of the uterine spiral arteries were suppressed by prematurely elevating estradiol levels in early pregnancy. We propose that estrogen normally controls the extent to which the uterine arteries are transformed by placental EVT in primate pregnancy by regulating expression of VEGF and particular integrin extracellular remodeling molecules that mediate this process. PMID:22495671

Bonagura, Thomas W.; Babischkin, Jeffery S.; Aberdeen, Graham W.; Pepe, Gerald J.

2012-01-01

121

Evaluation of preferable insertion routes for esophagogastroduodenoscopy using ultrathin endoscopes  

PubMed Central

AIM: To evaluate the discomfort associated with esophagogastroduodenoscopy (EGD) using an ultrathin endoscope through different insertion routes. METHODS: This study (January 2012-March 2013) included 1971 consecutive patients [male/female (M/F), 1158/813, 57.5 11.9 years] who visited a single institute for annual health checkups. Transnasal EGD was performed in 1394 patients and transoral EGD in 577. EGD-associated discomfort was assessed using a visual analog scale score (VAS score: 0-10). RESULTS: Multivariate analysis revealed gender (M vs F: 4.02 2.15 vs 5.06 2.43) as the only independent predictor of the VAS score in 180 patients who underwent EGD for the first time; whereas it revealed gender (M vs F 3.60 2.20 vs 4.84 2.37), operator, age group (A: < 39 years; B: 40-49 years; C: 50-59 years; D: 60-69 years; E: > 70 years; A/B/C/D/E: 4.99 2.32/4.34 2.49/4.19 2.31/3.99 2.27/3.63 2.31), and type of insertion as independent predictors in the remaining patients. Subanalysis for gender, age group, and insertion route revealed that the VAS score decreased with age regardless of gender and insertion route, was high in female patients regardless of age and insertion route, and was low in males aged over 60 years who underwent transoral insertion. CONCLUSION: Although comprehensive analysis revealed that the insertion route may not be an independent predictor of the VAS score, transoral insertion may reduce EGD-associated discomfort in elderly patients. PMID:24803817

Ono, Satoshi; Niimi, Keiko; Fujishiro, Mitsuhiro; Takahashi, Yu; Sakaguchi, Yoshiki; Nakayama, Chiemi; Minatsuki, Chihiro; Matsuda, Rie; Hirayama-Asada, Itsuko; Tsuji, Yosuke; Mochizuki, Satoshi; Kodashima, Shinya; Yamamichi, Nobutake; Ozeki, Atsuko; Matsumoto, Lumine; Ohike, Yumiko; Yamazaki, Tsutomu; Koike, Kazuhiko

2014-01-01

122

Phosphorus sorption capacities and physicochemical properties of nine substrate materials for constructed wetland  

SciTech Connect

Constructed wetland (CW) is a promising technique for removal of pollutants from wastewater and agricultural runoff. The performance of a CW to remove pollutants, however, hinges on the use of suitable substrate materials. This study examined the physicochemical properties and phosphorus (P) sorption capacities of nine different CW substrate materials using both batch experiments and the Freundlich as well as the Langmuir isotherm. The nine substrate materials used in this study were turf, topsoil, gravel, midsized sand (MSS), blast furnace slag (BFS), coal burn slag (CBS), blast furnace artificial slag (BFAS), coal burn artificial slag (CBAS), and midsized artificial sand (MSAS). Experimental data showed that sorption of P increased with initial solution P concentrations for all nine substrate materials. The maximum P sorption capacity of the substrate materials estimated by Langmuir isotherm was in the following order: turf (4243 mg/kg substrate) > BFAS (2116 mg/kg substrate) > BFS (1598 mg/kg substrate) > CBS (1449 mg/kg substrate) > top soil (1396 mg/kg substrate) > CBAS (1194 mg/kg substrate) > MSAS (519 mg/kg substrate) > gravel (494 mg/kg substrate) > MSS (403 mg/kg substrate). The specific gravity of eight substrate materials (except gravel) had very significant negative correlations with the P sorption, whereas the particle diameter of D-60 and uniformity coefficient (K-60) had positive correlations with the P sorption. The cation exchange capacity, organic matter, available ferrous, and exchangeable aluminum of the eight substrate materials also had very significant positive correlations with the P sorption, while the pH of the substrate materials showed a very significant negative correlation with the P sorption. Our study further suggests that turf and CBAS are the two relatively ideal substrate materials suitable for removal of P from a CW system.

Cui, L.H.; Zhu, X.Z.; Ma, M.; Ouyang, Y.; Dong, M.; Zhu, W.L.; Luo, S.M. [South China Agricultural University, Guangdong (China)

2008-08-15

123

Electrostatic Redesign of the [Myoglobin, Cytochrome b5] Interface to Create a Well-Defined Docked Complex with Rapid Inter-Protein Electron Transfer  

PubMed Central

Cyt b5 is the electron-carrier repair protein that reduces met-Mb and met-Hb to their O2-carrying ferroheme forms. Studies of electron transfer (ET) between Mb and cyt b5 revealed that they react on a Dynamic Docking (DD) energy landscape on which binding and reactivity are uncoupled: binding is weak and involves an ensemble of nearly isoenergetic configurations, only a few of which are reactive; those few contribute negligibly to binding. We set the task of redesigning the surface of Mb so that its reaction with cyt b5 instead would occur on a conventional simple docking (SD) energy landscape, on which a complex exhibits a well-defined (set of) reactive binding configuration(s), with binding and reactivity thus no longer being decoupled. We prepared a myoglobin (Mb) triple mutant (D44K/D60K/E85K; Mb(+6)) substituted with Zn-deuteroporphyrin, and monitored cytochrome b5 (cyt b5) binding and electron transfer (ET) quenching of the 3ZnMb(+6) triplet state. In contrast, to Mb(WT), the three charge-reversals around the front-face heme edge of Mb(+6) have directed cyt b5 to a surface area of Mb adjacent to its heme, created a well-defined, most-stable structure that supports good ET pathways, and apparently coupled binding and ET: both Ka and ket are increased by the same factor of ~ 2102, creating a complex that exhibits a large ET rate constant, ket = 106 1s?1, and is in slow exchange (koff ? ket). In short, these mutations indeed appear to have created the sought-for conversion from DD to simple docking (SD) energy landscapes. PMID:19419145

Xiong, Peng; Nocek, Judith M.; Griffin, Amanda K. K.; Wang, Jingyun; Hoffman, Brian M.

2010-01-01

124

Inferring Cirrus Size Distributions Through Satellite Remote Sensing and Microphysical Databases  

NASA Technical Reports Server (NTRS)

Since cirrus clouds have a substantial influence on the global energy balance that depends on their microphysical properties, climate models should strive to realistically characterize the cirrus ice particle size distribution (PSD), at least in a climatological sense. To date, the airborne in situ measurements of the cirrus PSD have contained large uncertainties due to errors in measuring small ice crystals (D<60 m). This paper presents a method to remotely estimate the concentration of the small ice crystals relative to the larger ones using the 11- and 12- m channels aboard several satellites. By understanding the underlying physics producing the emissivity difference between these channels, this emissivity difference can be used to infer the relative concentration of small ice crystals. This is facilitated by enlisting temperature-dependent characterizations of the PSD (i.e., PSD schemes) based on in situ measurements. An average cirrus emissivity relationship between 12 and 11 m is developed here using the Moderate Resolution Imaging Spectroradiometer (MODIS) satellite instrument and is used to retrieve the PSD based on six different PSD schemes. The PSDs from the measurement-based PSD schemes are compared with corresponding retrieved PSDs to evaluate differences in small ice crystal concentrations. The retrieved PSDs generally had lower concentrations of small ice particles, with total number concentration independent of temperature. In addition, the temperature dependence of the PSD effective diameter De and fall speed Vf for these retrieved PSD schemes exhibited less variability relative to the unmodified PSD schemes. The reduced variability in the retrieved De and Vf was attributed to the lower concentrations of small ice crystals in the retrieved PSD.

Mitchell, David; D'Entremont, Robert P.; Lawson, R. Paul

2010-01-01

125

Combined use of a transformed red mud reactive barrier and electrokinetics for remediation of Cr/As contaminated soil.  

PubMed

A reactive barrier (RB) of transformed red mud (TRM), a by-product of the refinement of bauxite in alumina production, was placed adjacent to the anode of an electrokinetic (EK) system with the aim of enhancing removal of chromium or arsenic, added singly to a low permeability clayey soil, and favouring entrapment. The innovative study focused on evaluation of the synergic interaction between the EK system and the RB, and of the efficiency when compared to traditional EK remediation (control tests). The results obtained underlined the successful outcome of treatment of the Cr(VI)-contaminated soil. In presence of the TRM RB, 19.4% wt. of total Cr content was detected in the anolyte and 20.6% wt. trapped in the anodic RB after 6d, versus 6.6% wt. in the anolyte and 8.8% wt. in the soil adjacent to the anode following the control run without RB. On increasing duration of treatment up to 12d, 60.8% wt. of total initial Cr was found in the anolyte and 25.5% wt. trapped in the RB, versus 9.1% wt. and 5.3% wt., respectively, after a control run of the same duration. Finally, on increasing the mass of TRM in the RB, 60.6% wt. of initial Cr content was found to have accumulated in the RB, with Cr being completely absent from the anodic chamber. Conversely, combined treatment was much less effective on As contaminated soil, at least under the operative conditions applied. Low initial As concentration and interference with iron oxides in the soil were likely the reasons underlying low efficiency while attempting As decontamination. PMID:22119416

Cappai, G; De Gioannis, G; Muntoni, A; Spiga, D; Zijlstra, J J P

2012-01-01

126

Generalized Polynomial Chaos Based Uncertainty Quantification for Planning MRgLITT Procedures  

PubMed Central

Purpose A generalized polynomial chaos (gPC) method is used to incorporate constitutive parameter uncertainties within the Pennes representation of bioheat transfer phenomena. The stochastic temperature predictions of the mathematical model are critically evaluated against MR thermometry data for planning MR-guided Laser Induced Thermal Therapies (MRgLITT). Methods Pennes bioheat transfer model coupled with a diffusion theory approximation of laser tissue interaction was implemented as the underlying deterministic kernel. A probabilistic sensitivity study was used to identify parameters that provide the most variance in temperature output. Confidence intervals of the temperature predictions are compared to MR temperature imaging (MRTI) obtained during phantom and in vivo canine (n=4) MRgLITT experiments. The gPC predictions were quantitatively compared to MRTI data using probabilistic linear and temporal profiles as well as 2-D 60 C isotherms. Results Within the range of physically meaningful constitutive values relevant to the ablative temperature regime of MRgLITT, the sensitivity study indicated that the optical parameters, particularly the anisotropy factor, created the most variance in the stochastic model's output temperature prediction. Further, within the statistical sense considered, a nonlinear model of the temperature and damage dependent perfusion, absorption, and scattering is captured within the confidence intervals of the linear gPC method. Multivariate stochastic model predictions using parameters with the dominant sensitivities show good agreement with experimental MRTI data. Conclusions Given parameter uncertainties and mathematical modeling approximations of the Pennes bioheat model, the statistical framework demonstrates conservative estimates of the therapeutic heating and has potential for use as a computational prediction tool for thermal therapy planning. PMID:23692295

Fahrenholtz, S.; Stafford, R. J.; Maier, F.; Hazle, J. D.; Fuentes, D.

2014-01-01

127

Distribution of seismicity across strike-slip faults in California  

NASA Astrophysics Data System (ADS)

The distribution of seismicity about strike-slip faults provides measurements of fault roughness and damage zone width. In California, seismicity decays with distance from strike-slip faults according to a power law (1 + x2/d2)-?/2. This scaling relation holds out to a fault-normal distance x of 3-6 km and is compatible with a "rough fault loading" model in which the inner scale d measures the half width of a volumetric damage zone and the roll-off rate ? is governed by stress variations due to fault roughness. According to Dieterich and Smith's 2-D simulations, ? approximates the fractal dimension of along-strike roughness. Near-fault seismicity is more localized on faults in northern California (NoCal, d = 60 20 m, ? = 1.65 .05) than in southern California (SoCal, d = 220 40 m, ? = 1.16 .05). The Parkfield region has a damage zone half width (d = 120 30 m) consistent with the SAFOD drilling estimate; its high roll-off rate (? = 2.30 .25) indicates a relatively flat roughness spectrum: k-1 versus k-2 for NoCal, k-3 for SoCal. Our damage zone widths (the first direct estimates averaged over the seismogenic layer) can be interpreted in terms of an across-strike "fault core multiplicity" that is 1 in NoCal, 2 at Parkfield, and 3 in SoCal. The localization of seismicity near individual faults correlates with cumulative offset, seismic productivity, and aseismic slip, consistent with a model in which faults originate as branched networks with broad, multicore damage zones and evolve toward more localized, lineated features with low fault core multiplicity, thinner damage zones, and less seismic coupling. Our results suggest how earthquake triggering statistics might be modified by the presence of faults.

Powers, Peter M.; Jordan, Thomas H.

2010-05-01

128

Is Prostate Biopsy Essential to Diagnose Prostate Cancer in the Older Patient with Extremely High Prostate-Specific Antigen?  

PubMed Central

Purpose The results of all prostate biopsies may be positive and suggestive of adenocarcinoma in patients with prostate-specific antigen (PSA) values higher than 100 ng/ml. We considered that the prostate cancer in patients with high PSA might be advanced disease and therefore that the treatment strategy should not be changed according to pathological reports. Thus, we assessed the role of prostate biopsy when diagnosing prostate cancer in patients with extremely high PSA levels. Materials and Methods We reviewed the records of 1,150 cases undergoing prostate biopsies. Patients with urinary tract infection and acute urinary retention were excluded. According to the pre-biopsy PSA level, patients were divided into 6 groups (group A, 4 to 20 ng/ml; B, 20 to 40 ng/ml; C, 40 to 60 ng/ml; D, 60 to 80 ng/ml; E: 80 to 100 ng/ml; and F, above 100 ng/ml). Results The calculated positive predictive value (PPV) for prostate cancer was 22% in group A, 54% in group B, 73% in group C, 75% in group D, 89% in group E, and 100% in group F, respectively. Pathological diagnosis was adenocarcinoma in all patients in group F (n=56). Among them, 38 patients (67.9%) had lymph node metastasis or extra-prostatic disease or both and 43 patients (76.8%) had bony metastasis. In group F, all cases were advanced prostate cancer (stage III or IV). All of them received hormonal therapy following diagnosis. Conclusions We suggest the possibility for biopsy-free diagnosis of prostate cancer in patients with extremely high levels of serum PSA and evidence of advanced disease in imaging studies, especially in older patients with comorbid medical problems. PMID:22379585

Jang, Jee Young

2012-01-01

129

The effect of patient age on the success of laryngeal reinnervation.  

PubMed

The objective of the study was to investigate the influence of patient age on the efficacy of laryngeal reinnervation with ansa cervicalis in unilateral vocal fold paralysis (UVFP) patients. We retrospectively reviewed 349 consecutive UVFP cases of laryngeal reinnervation with ansa cervicalis to the recurrent laryngeal nerve anastomosis. Preoperative and postoperative videostroboscopy, perceptual evaluation, acoustic analysis, maximum phonation time (MPT) and laryngeal electromyography (EMG) data were collected. Gender, age, preoperative EMG status [preoperative voluntary motor unit recruitment (VMUR)] and denervation duration were analyzed in previous multivariable logistic regression analysis. Stratification analysis was performed on patient age in the present study. All patients were divided into four groups according to their age: Group A included patients with an age less than 30years; Group B, 30-44years; Group C, 45-59years; Group D, ?60years. Stratification analysis on patient age showed significant differences between Group A and D, Group B and D, Group C and D (P<0.05), but no significant difference between Group A and B, Group A and C, Group B and C (P>0.05), respectively, with regard to parameters including glottal closure, overall grade, shimmer, noise-to-harmonics ratio; but there are no significant differences among the four groups with regard to jitter. However, for MPT and postoperative VMUR, there are significant differences among the four groups expect between Group A and B. In addition, glottal closure, perceptual and acoustic parameters, MPT values and VMUR data, were significantly improved postoperatively in each age group (P<0.01). The data from this study indicate that patient age is an influential factor of the surgical outcome of laryngeal reinnervation for UVFP patients. Laryngeal reinnervation is less effective when patient age is more than 60years. PMID:24913623

Li, Meng; Chen, Donghui; Song, Xianmin; Wang, Wei; Zhu, Minhui; Liu, Fei; Li, Yan; Chen, Shicai; Zheng, Hongliang

2014-12-01

130

THE PARSEC-SCALE ENVIRONMENT AND THE EVOLUTIONARY STATUS OF MWC 349A  

SciTech Connect

We report on a study of the ?10' (?5 pc in projection) environs of the peculiar, high-luminosity emission-line star MWC 349A in the IR, radio, and visible domains. Besides the recently discovered X-shaped, arcmin-scale IR nebula centered on MWC 349A ({sup X} nebula{sup )}, with the kinematic age of ?10{sup 4} yr, we identify several young objects pointing toward an ongoing process of active star formation in this region and estimate some physical parameters of the newly discovered objects. The radiation of the X nebula is due to a geometrically and optically thin dust front heated to T{sub d} ? 60-70 K by the radiation of the central star. The bipolar dust front probably results from the interaction of a powerful stellar wind with the circumstellar disk. One of the related objects is an elongated, cold molecular cloud, ?1 pc in size, adjacent to MWC 349A in projection and having the same radial velocity (V{sub LSR} ? +9 km s{sup 1}). The proximity of the molecular cloud may indicate that MWC 349A was born locally rather than being a runaway object ejected from the core of Cyg OB2 several Myr ago. If it is still associated with its natal cloud, MWC 349A may be a rare example of the observable pre-main-sequence stage of a ?30 M{sub ?} star. If the association with the molecular cloud is an effect of projection, however, MWC 349A may already be an evolved star, even if it was born locally. We discuss future observations that may shed more light on the evolutionary status of this unique object.

Strelnitski, Vladimir; Armstrong, Peter; Lagergren, Krister; Walker, Gary [Maria Mitchell Observatory, 4 Vestal Street, Nantucket, MA 02554 (United States); Bieging, John H. [Steward Observatory, The University of Arizona, Tucson, AZ 85721 (United States); Hora, Joseph; Smith, Howard A., E-mail: vladimir@mariamitchell.org, E-mail: bailyhill14@gmail.com, E-mail: PeterArmstrong@limpiaobservatory.com, E-mail: jbieging@as.arizona.edu, E-mail: jhora@cfa.harvard.edu, E-mail: hsmith@cfa.harvard.edu, E-mail: kal7q@virginia.edu [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

2013-11-10

131

Detergency stability and particle characterization of phosphate-free spray dried detergent powders incorporated with palm C16 methyl ester sulfonate (C16MES).  

PubMed

Phosphate-free spray dried detergent powders (SDDP) comprising binary anionic surfactants of palm C16 methyl ester sulfonate (C16MES) and linear alkyl benzene sulfonic acid (LABSA) were produced using a 5 kg/h-capacity co-current pilot spray dryer (CSD). Six phosphate-free detergent (PFD) formulations comprising C16MES/LABSA in various ratios under pH 7-8 were studied. Three PFD formulations having C16MES/LABSA in respective ratios of 0:100 (control), 20:80 and 40:60 ratios were selected for further evaluation based on their optimum detergent slurry concentrations. The resulting SDDP from these formulations were analysed for its detergency stability (over nine months of storage period) and particle characteristics. C16MES/LABSA of 40:60 ratio was selected as the ideal PFD formulation since its resulting SDDP has consistent detergency stability (variation of 2.3% in detergency/active over nine months storage period), excellent bulk density (0.37 kg/L), fine particle size at 50% cumulative volume percentage (D50 of 60.48 ?m), high coefficient of particle size uniformity (D60/D10 of 3.86) and large spread of equivalent particle diameters. In terms of surface morphology, the SDDP of the ideal formulation were found to have regular hollow particles with smooth spherical surfaces. Although SDDP of the ideal formulation have excellent characteristics, but in terms of flowability, these powders were classified as slightly less free flowing (Hausner ratio of 1.27 and Carr's index of 21.3). PMID:24829132

Siwayanan, Parthiban; Aziz, Ramlan; Bakar, Nooh Abu; Ya, Hamdan; Jokiman, Ropien; Chelliapan, Shreeshivadasan

2014-01-01

132

Enlarging the Toolbox for Allergen Epitope Definition with an Allergen-Type Model Protein  

PubMed Central

Background Birch pollen-allergic subjects produce polyclonal cross-reactive IgE antibodies that mediate pollen-associated food allergies. The major allergen Bet v 1 and its homologs in plant foods bind IgE in their native protein conformation. Information on location, number and clinical relevance of IgE epitopes is limited. We addressed the use of an allergen-related protein model to identify amino acids critical for IgE binding of PR-10 allergens. Method Norcoclaurine synthase (NCS) from meadow rue is structurally homologous to Bet v 1 but does not bind Bet v 1-reactive IgE. NCS was used as the template for epitope grafting. NCS variants were tested with sera from 70 birch pollen allergic subjects and with monoclonal antibody BV16 reported to compete with IgE binding to Bet v 1. Results We generated an NCS variant (?29NCSN57/I58E/D60N/V63P/D68K) harboring an IgE epitope of Bet v 1. Bet v 1-type protein folding of the NCS variant was evaluated by 1H-15N-HSQC NMR spectroscopy. BV16 bound the NCS variant and 71% (50/70 sera) of our study population showed significant IgE binding. We observed IgE and BV16 cross-reactivity to the epitope presented by the NCS variant in a subgroup of Bet v 1-related allergens. Moreover BV16 blocked IgE binding to the NCS variant. Antibody cross-reactivity depended on a defined orientation of amino acids within the Bet v 1-type conformation. Conclusion Our system allows the evaluation of patient-specific epitope profiles and will facilitate both the identification of clinically relevant epitopes as biomarkers and the monitoring of therapeutic outcomes to improve diagnosis, prognosis, and therapy of allergies caused by PR-10 proteins. PMID:25356997

Hartl, Maximilian; Randow, Stefanie; Gubesch, Michaela; Vogel, Lothar; Husslik, Felix; Reuter, Andreas; Lidholm, Jonas; Ballmer-Weber, Barbara; Vieths, Stefan; Rsch, Paul; Schiller, Dirk

2014-01-01

133

Variability in the resistance of the Nigerian West African Dwarf goat to abbreviated escalating trickle and challenge infections with Haemonchus contortus.  

PubMed

The West African Dwarf (WAD) goat is known to be relatively resistant to infection with Haemonchus contortus. An experiment was carried out to assess variability in resistance under escalating trickle and single pulse challenge infection protocols. Thirty two 7-8 month old goats were subjected to trickle infection beginning with a thrice weekly dose of 100 L3 and increasing to 500 L3 by week 5, the last dose being administered on D30. Infection was abbreviated with fenbendazole on D32 and the animals challenged with 4000 L3 (=404-741L3/kg body weight) on D46 and necropsied on D81. The goats exhibited marked individual variability in faecal egg counts (FEC) and worm burdens (Wb). For convenience, we arranged the goats into FEC classes 1, 2 and 3, corresponding to peak counts of <1000, 1000-2500 and >2500 epg and Wb classes 1, 2 and 3, with counts of <50, 50-100 and >100 worms, respectively, broadly reflecting relatively resistant, intermediate and poorly resistant response phenotypes. Wb classes broadly reflected the FEC phenotypes and although there were no significant differences between the Wb of the FEC classes at necropsy, significant differences in FEC were detected when analysis was carried out only on Wb classes. There was also a significant positive correlation between FEC class on each of the days of challenge (D67 to D80) and worm burden at necropsy. In general, the goats showed strong resistance/tolerance to challenge, with more than 80% having Wb not exceeding 5% of the challenge dose, and only in class three goats were weight loss and anaemia detected in some animals. PCV and weight changes also closely reflected the FEC and Wb classes, with a significant negative correlation between each and Wb. Infection level did not significantly affect the sizes of either male or female worms and no significant difference was detected between the levels of circulating eosinophils in any FEC or Wb class. Overall, the data are consistent with the existence of a range of response phenotypes, which reflect variations in resistance of WAD goats to H. contortus infection, the genetic basis of which will be explored in future experiments. PMID:15158556

Fakae, B B; Musongong, G A; Chiejina, S N; Behnke, J M; Ngongeh, L A; Wakelin, D

2004-06-10

134

The cold veil of the Milky Way stellar halo  

NASA Astrophysics Data System (ADS)

We build a sample of distant (D > 80 kpc) stellar halo stars with measured radial velocities. Faint (20 < g < 22) candidate blue horizontal branch (BHB) stars were selected using the deep, but wide, multi-epoch Sloan Digital Sky Survey photometry. Follow-up spectroscopy for these A-type stars was performed using the Very Large Telescope (VLT) FOcal Reducer and low dispersion Spectrograph 2 (FORS2) instrument. We classify stars according to their Balmer line profiles, and find that seven are bona fide BHB stars and 31 are blue stragglers (BS). Owing to the magnitude range of our sample, even the intrinsically fainter BS stars can reach out to D 90 kpc. We complement this sample of A-type stars with intrinsically brighter, intermediate-age, asymptotic giant branch stars. A set of four distant cool carbon stars is compiled from the literature and we perform spectroscopic follow-up on a further four N-type carbon stars using the William Herschel Telescope (WHT) Intermediate dispersion Spectrograph and Imaging System (ISIS) instrument. Altogether, this provides us with the largest sample to date of individual star tracers out to r 150 kpc. We find that the radial velocity dispersion of these tracers falls rapidly at large distances and is surprisingly cold (?r ? 50-60 km s-1) between 100 and 150 kpc. Relating the measured radial velocities to the mass of the Milky Way requires knowledge of the (unknown) tracer density profile and anisotropy at these distances. Nonetheless, by assuming the stellar halo stars between 50 and 150 kpc have a moderate density fall-off (with power-law slope ? < 5) and are on radial orbits (?t2/?r2<1), we infer that the mass within 150 kpc is less than 1012 M? and suggest it probably lies in the range (5-10) 1011 M?. We discuss the implications of such a low mass for the Milky Way. Based on observations made with European Southern Observatory Telescopes at the La Silla Paranal Observatory under programme ID 085.B-0567(A) and 088.B-0476(A). Based on observations made with the William Herschel Telescope operated on the island of La Palma by the Isaac Newton Group in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofsica de Canarias.Ramn y Cajal Fellow.Hubble Fellow.

Deason, A. J.; Belokurov, V.; Evans, N. W.; Koposov, S. E.; Cooke, R. J.; Pearrubia, J.; Laporte, C. F. P.; Fellhauer, M.; Walker, M. G.; Olszewski, E. W.

2012-10-01

135

On the study of vortex-induced vibration of a cylinder with helical strakes  

NASA Astrophysics Data System (ADS)

While the effect of helical strakes on suppression of Vortex-Induced Vibrations (VIV) has been studied extensively, the mechanism of VIV mitigation using helical strakes is much less well documented in the literature. In the present study, a rigid circular cylinder of diameter d =80 mm attached with three-strand helical strakes of dimensions of 10 d in pitch and 0.12 d in height was tested in a wind tunnel. It was found that the helical strakes can reduce VIV by about 98%. Unlike the bare cylinder, which experiences lock-in over the reduced velocity in the range of 5-8.5, the straked cylinder does not show any lock-in region. In exploring the mechanism of VIV reduction by helical strakes, measurements in stationary bare and straked cylinder wakes using both a single X-probe at four different Reynolds numbers, i.e. Re=10 240, 20 430, 30 610 and 40 800, and two X-probes with variable separations in the spanwise direction at R e=20 430 were conducted. It was found that vortices shed from the straked cylinder are weakened significantly. The dominate frequency varies by about 30% over the range of x / d =10-40 in the streamwise direction while that differs by about 37.2% of the averaged peak frequency over a length of 3.125 d in the spanwise direction. The latter is supported by the phase difference between the velocity signals measured at two locations separated in the spanwise direction. The correlation length of the vortex structures in the bare cylinder wake is much larger than that obtained in the straked cylinder wake. As a result, the straked cylinder wake agrees more closely with isotropy than the bare cylinder wake. Flow visualization on the plane perpendicular to the cylinder axis at Reynolds number of about 300 reveals small-scale vortices in the shear layers of the straked cylinder wake. However, these vortices do not roll up and interact with each other to form the well-organized Karman-type vortices. Flow visualization on the plane parallel to the cylinder axis shows vortex dislocation and swirling flow, which should be responsible for the variations of the peak frequency in the streamwise as well as spanwise directions.

Zhou, T.; Razali, S. F. Mohd.; Hao, Z.; Cheng, L.

2011-10-01

136

Aerosol and NOx emission factors and submicron particle number size distributions in two road tunnels with different traffic regimes  

NASA Astrophysics Data System (ADS)

Measurements of aerosol particle number size distributions (18-700 nm), mass concentrations (PM2.5 and PM10) and NOx were performed in the Plabutsch tunnel, Austria, and in the Kingsway tunnel, United Kingdom. These two tunnels show different characteristics regarding the roadway gradient, the composition of the vehicle fleet and the traffic frequency. The submicron particle size distributions contained a soot mode in the diameter range D=80-100 nm and a nucleation mode in the range of D=20-40 nm. In the Kingsway tunnel with a significantly lower particle number and volume concentration level than in the Plabutsch tunnel, a clear diurnal variation of nucleation and soot mode particles correlated to the traffic density was observed. In the Plabutsch tunnel, soot mode particles also revealed a diurnal variation, whereas no substantial variation was found for the nucleation mode particles. During the night a higher number concentration of nucleation mode particles were measured than soot mode particles and vice versa during the day. In this tunnel with very high soot emissions during daytime due to the heavy-duty vehicle (HDV) share of 18% and another 40% of diesel driven light-duty vehicles (LDV) semivolatile species condense on the pre-existing soot surface area rather than forming new particles by homogeneous nucleation. With the low concentration of soot mode particles in the Kingsway tunnel, also the nucleation mode particles exhibit a diurnal variation. From the measured parameters real-world traffic emission factors were estimated for the whole vehicle fleet as well as differentiated into the two categories LDV and HDV. In the particle size range D=18-700 nm, each vehicle of the mixed fleet emits (1.500.08)1014 particles km-1 (Plabutsch) and (1.260.10)1014 particles km-1 (Kingsway), while particle volume emission factors of 0.2090.008 cm3 km-1 and 0.0360.004 cm3 km-1, respectively, were obtained. PM1 emission factors of 1044 mg km-1 (Plabutsch) and 414 mg km-1 (Kingsway) were calculated. Emission factors determined in this work were in good agreement with results from other studies.

Imhof, D.; Weingartner, E.; Prvt, A. S. H.; Ordez, C.; Kurtenbach, R.; Wiesen, P.; Rodler, J.; Sturm, P.; McCrae, I.; Ekstrm, M.; Baltensperger, U.

2006-06-01

137

Structural peculiarities and Raman spectra of TeO{sub 2}/WO{sub 3}-based glasses: A fresh look at the problem  

SciTech Connect

Ideas currently dominating the field of structural studies of TeO{sub 2}-based glasses are critically considered. A new physically and chemically consistent approach to the constitution of binary TeO{sub 2}-WO{sub 3} glasses is proposed, in which the reasoning coming from the Raman spectra reexamination are correlated with the basic principles of thermodynamics. Separation into two phases is suggested in such glasses. One phase is TeO{sub 2}, and another is Te(WO{sub 4}){sub 2} consisting of tetrahedral [WO{sub 4}]{sup 2-} anions and of Te{sup 4+} cations. Supplementary M{sub n}O{sub k} oxides added to the glasses are found incorporated in the former phase, thus producing solid solutions (for M=Ti, Nb) or tellurite compounds (for M=Nd). - Graphical abstract: Raman scattering spectra of TeO{sub 2}-based glasses with the following compositions (mol%): (a) pure TeO{sub 2}, (b) 85TeO{sub 2}-15WO{sub 3}, (c) 80TeO{sub 2}-15WO{sub 3}-5TiO{sub 2} ,(d) 80TeO{sub 2}-10WO{sub 3}-5TiO{sub 2}-5Nb{sub 2}O{sub 5}, (e) 80TeO{sub 2}-12WO{sub 3}-5TiO{sub 2}-3 Nd{sub 2}O{sub 3}, (f) 80TeO{sub 2}-10WO{sub 3}-5TiO{sub 2}-5Nd{sub 2}O{sub 3}. Highlights: Black-Right-Pointing-Pointer Structural studies of TeO{sub 2}-WO{sub 3} glasses are critically considered. Black-Right-Pointing-Pointer The oxide glass formation is analyzed from Raman spectra and thermodynamic principles. Black-Right-Pointing-Pointer Separation into two phases, TeO{sub 2} and Te(WO{sub 4}){sub 2}, is intrinsic in such glasses. Black-Right-Pointing-Pointer TiO{sub 2} or Nb{sub 2}O{sub 5} addition to TeO{sub 2}-WO{sub 3} glasses leads to produce solid solutions. Black-Right-Pointing-Pointer Nd{sub 2}O{sub 3} addition to TeO{sub 2}-WO{sub 3} glasses leads to produce a tellurite compound.

Mirgorodsky, Andreie; Colas, Maggy [Laboratoire Science des Procedes Ceramiques et de Traitements de Surface, UMR 6638 CNRS, Centre Europeen de la Ceramique, 12 rue Atlantis, 87068 Limoges Cedex (France); Smirnov, Mikhael [Fock Institute of Physics, Saint-Petersburg State University, 1 Ulyanovskaya street, 198504, Petrodvorets, Saint-Petersburg (Russian Federation); Merle-Mejean, Therese [Laboratoire Science des Procedes Ceramiques et de Traitements de Surface, UMR 6638 CNRS, Centre Europeen de la Ceramique, 12 rue Atlantis, 87068 Limoges Cedex (France); El-Mallawany, Raouf [Physics Department, Science College, Northern Borders University (Saudi Arabia); Thomas, Philippe, E-mail: philippe.thomas@unilim.fr [Laboratoire Science des Procedes Ceramiques et de Traitements de Surface, UMR 6638 CNRS, Centre Europeen de la Ceramique, 12 rue Atlantis, 87068 Limoges Cedex (France)

2012-06-15

138

Direct imaging of extra-solar planets in star forming regions. Lessons learned from a false positive around IM Lupi  

NASA Astrophysics Data System (ADS)

Context. Most exoplanet imagers consist of ground-based adaptive optics coronagraphic cameras which are currently limited in contrast, sensitivity and astrometric precision, but advantageously observe in the near-infrared window (1-5 ?m). Because of these practical limitations, our current observational aim at detecting and characterizing planets puts heavy constraints on target selection, observing strategies, data reduction, and follow-up. Most surveys so far have thus targeted young systems (1-100 Myr) to catch the putative remnant thermal radiation of giant planets, which peaks in the near-infrared. They also favor systems in the solar neighborhood (d < 80 pc), which eases angular resolution requirements but also ensures a good knowledge of the distance and proper motion, which are critical to secure the planet status, and enable subsequent characterization. Aims: Because of their youth, it is very tempting to target the nearby star forming regions, which are typically twice as far as the bulk of objects usually combed for planets by direct imaging. Probing these interesting reservoirs sets additional constraints that we review in this paper by presenting the planet search that we initiated in 2008 around the disk-bearing T Tauri star IM Lup, which is part of the Lupus star forming region (140-190 pc). Methods: We show and discuss why age determination, the choice of evolutionary model for both the central star and the planet, precise knowledge of the host star proper motion, relative or absolute (between different instruments) astrometric accuracy (including plate scale calibration), and patience are the key ingredients for exoplanet searches around more distant young stars. Results: Unfortunately, most of the time, precision and perseverance are not paying off: we discovered a candidate companion around IM Lup in 2008, which we report here to be an unbound background object. We nevertheless review in details the lessons learned from our endeavor, and additionally present the best detection limits ever calculated for IM Lup. We also accessorily report on the successful use of innovative data reduction techniques, such as the damped-LOCI and iterative roll subtraction. Based on the ESO observing programs 380.C-0910, 084.C-0444, 287.C-5040; and HST observing program 10177.

Mawet, D.; Absil, O.; Montagnier, G.; Riaud, P.; Surdej, J.; Ducourant, C.; Augereau, J.-C.; Rttinger, S.; Girard, J.; Krist, J.; Stapelfeldt, K.

2012-08-01

139

Specific VpU codon changes were significantly associated with gp120 V3 tropic signatures in HIV-1 B-subtype.  

PubMed

After infection and integration steps, HIV-1 transcriptions increase sharply and singly-spliced mRNAs are produced. These encode Env (gp120 and gp41) and auxiliary proteins Vif, Vpr and VpU. The same localization within the unique structure of the mRNAs suggests that the VpU sequence prior to the Env could affect the Env polyprotein expression.The HIV-1 infection process begins when the gp120 subunit of the envelope glycoprotein complex interacts with its receptor(s) on the target cell. The V3 domain of gp120 is the major determinant of cellular co-receptor binding. According to phenotypic information of HIV-1 isolates, sequences from the VpU to V3 regions (119 in R5- and 120 X4-tropic viruses; one per patient) were analysed. The binomial correlation phi coefficient was used to assess covariation among VpU and gp120(V3) signatures. Subsequently, average linkage hierarchical agglomerative clustering was performed. Beyond the classical V3 signatures (R5-viruses: S11, E25D; X4-viruses: S11KR, E25KRQ), other specific V3 and novel VpU signatures were found to be statistically associated with co-receptor usage. Several statistically significant associations between V3 and VpU mutations were also observed. The dendrogram showed two distinct large clusters: one associated with R5-tropic sequences (bootstrap=0.94), involving: (a) H13NP(V3), E25D(V3), S11(V3), T22A(V3) and Q61H(VpU), (b) E25A(V3) and L12F(VpU), (c) D44E(VpU), R18Q(V3) and D80N(VpU); and another associated with X4-tropic sequences (bootstrap=0.97), involving: (i) E25I(V3) and V10A(VpU), (ii) 0-1insV(VpU), H13R(V3), I46L(VpU), I30M(V3) and 60-62del(VpU), (iii) S11KR(V3) and E25KRQ(V3). Some of these pairs of mutations were encoded always by one specific codon. These data indicate the possible VpU mutational patterns contributing to regulation of HIV-1 tropism. PMID:23271577

Dimonte, Salvatore; Babakir-Mina, Muhammed; Aquaro, Stefano; Perno, Carlo-Federico

2012-12-01

140

Pressure drop, flow pattern and local water volume fraction measurements of oil-water flow in pipes  

NASA Astrophysics Data System (ADS)

Oil-water flow in horizontal and slightly inclined pipes was investigated. The experimental activities were performed using the multiphase flow loop at Telemark University College, Porsgrunn, Norway. The experiments were conducted in a 15 m long, 56 mm diameter, inclinable steel pipe using Exxsol D60 oil (density of 790 kg m-3 and viscosity of 1.64 mPa s) and water (density of 996 kg m-3 and viscosity of 1.00 mPa s) as test fluids. The test pipe inclination was changed in the range from 5 upward to 5 downward. Mixture velocity and inlet water cut vary up to 1.50 m s-1 and 0.975, respectively. The time-averaged cross-sectional distributions of oil and water were measured with a single-beam gamma densitometer. The pressure drop along the test section of the pipe was also measured. The characterization of flow patterns and identification of their boundaries are achieved via visual observations and by analysis of local water volume fraction measurements. The observed flow patterns were presented in terms of flow pattern maps for different pipe inclinations. In inclined flows, dispersions appear at lower mixture velocities compared to the horizontal flows. Smoothly stratified flows observed in the horizontal pipe disappeared in upwardly inclined pipes and new flow patterns, plug flow and stratified wavy flow were observed. The water-in-oil dispersed flow regime slightly shrinks as the pipe inclination increases. In inclined flows, the dispersed oil-in-water flow regime extended to lower mixture velocities and lower inlet water cuts. The present experimental data were compared with the results of a flow-pattern-dependent prediction model, which uses the area-averaged steady-state two-fluid model for stratified flow and the homogeneous model for dispersed flow. The two-fluid model was able to predict the pressure drop and water hold-up for stratified flow. The homogeneous model was not able to predict the pressure profile of dispersed oil-water flow at higher water cuts. The two-fluid model and the homogeneous model over-predict the pressure drop for dual-continuous flow.

Kumara, W. A. S.; Halvorsen, B. M.; Melaaen, M. C.

2009-11-01

141

Geophysical Characterization of the Borax Lake Hydrothermal System in the Alvord Desert, Southeastern Oregon.  

NASA Astrophysics Data System (ADS)

We are conducting a detailed geophysical characterization of an active hydrothermal system as part of an interdisciplinary project aiming to study the link between the physical characteristics of hydrothermal systems and biota that occupy those systems. The Borax Lake Hydrothermal System (BLHS), consisting of Borax Lake and the surrounding hot springs, is located near the center of the Alvord Basin in southeastern Oregon. As a result of Basin and Range extension, the Alvord Basin is a north-south trending graben bounded by the Steens Mountains to the west and the Trout Creek Mountains to the east. We are using several geophysical techniques to generate both basin-wide and high-resolution local characterizations of the Alvord Basin and the BLHS. To date we have completed two scales of seismic reflection surveys: an east-west trending basin scale survey and a shallow (~10 - 300 m depth) 3D survey of the BLHS. The basin scale seismic survey consists of 11 km of 2D, 60 fold CMP data acquired with a 200 lb accelerated weight drop. We acquired the 3D survey of the BLHS using a 7.62x39 mm SKS rifle and 240 channel recording system. The 3D patch covers ~ 90,000 sq. m with a maximum inline offset aperture of 225 m, crossline aperture of 75 m, and 360 degree azimuthal coverage. Additionally, we have completed a regional total-field magnetic survey for a large portion of the Alvord Basin and a 3D transient electromagnetic (TEM) survey of the BLHS. The 3D TEM survey covers the central portion of the 3D seismic survey. Initial results from the regional magnetic and seismic surveys indicate a mid-basin basement high. The basement high appears to correlate with the northeast trending BLHS. Additionally, the cross-basin seismic profile clearly shows that recent deformation has primarily been along an eastward dipping normal fault that bounds the basement high to the east. This suggests that both spatial and temporal characteristics of deformation control hydrothermal activity within the BLHS.

Hess, S.; Paul, C.; Bradford, J.; Lyle, M.; Clement, W.; Liberty, L.; Myers, R.; Donaldson, P.

2003-12-01

142

Glucocorticoids induce glutamine synthetase in folliculostellate cells of rat pituitary glands in vivo and in vitro  

PubMed Central

Glutamine synthetase (GS) is a glucocorticoid-inducible enzyme that has a key role for glutamate metabolism in the central and peripheral nervous system. In this study GS activity was measured and the amount of immunoreactive GS (ir-GS) cells in the rat anterior pituitary gland was quantified as a function of age. In addition, the effects of GS inhibitors, glucocorticoid administration, and adrenalectomy on GS activity were examined. Some of the ir-GS cells were also immunoreactive for S100 protein (ir-S100) which is a known marker for folliculostellate cells (FS) in the anterior pituitary. FS cells expressing GS were first detected in 3-d-old rats, and this cell population, expressed as the immunostained cell area divided by a standard unit area, increased as a function of age. The percentages of FS cells also expressing GS were 0.2, 6.4, 25 and 74% at 3 d, 30 d, 60 d and 2 y of age, respectively. GS enzyme activity also increased in parallel with the increase of ir-GS cell population maturation. The subcutaneous injection of methionine sulphoximine, a GS and ?-glutamylcysteine synthetase inhibitor, reduced pituitary GS activity by 83%, but increased the population of ir-GS cells 3.5-fold in 30-d-old rats. Buthionine sulphoximine, a specific inhibitor of ?-glutamylcysteine synthetase, had little effect on GS activity or the ir-GS cell population. Neither methionine sulphoximine nor buthionine sulphoximine changed the population of ir-S100 protein cells (FS cells). Dexamethasone and hydrocortisone increased the population of ir-GS cells by 3.1 and 4.2-fold, respectively, within 12 h after administration. A significant increase of GS activity due to the injection of glucocorticoids was observed in the anterior pituitary, but not in the brain, retina or liver of immature rats. Adrenalectomy did not cause decrease of pituitary GS activity, and dexamethasone administration increased GS activity in both adrenalectomised and intact rats. In the monolayer culture of anterior pituitary cells, glucocorticoids increased GS activity by 1.5, and methionine sulphoximine reduced the activity by over 94%. These results demonstrate that GS in folliculostellate cells is a glucocorticoid-inducible enzyme in vivo and in vitro, and that the age-dependent increase of GS activity is independent of endogenous adrenal glucocorticoids. PMID:10445824

SHIRASAWA, NOBUYUKI; YAMANOUCHI, HIROSHI

1999-01-01

143

Effect of heat stress during late gestation on immune function and growth performance of calves: Isolation of altered colostral and calf factors.  

PubMed

Calves born to cows exposed to heat stress during the dry period and fed their dams' colostrum have compromised passive and cell-mediated immunity compared with calves born to cows cooled during heat stress. However, it is unknown if this compromised immune response is caused by calf or colostrum intrinsic factors. Two studies were designed to elucidate the effects of colostrum from those innate to the calf. The objective of the first study was to evaluate the effect of maternal heat stress during the dry period on calf-specific factors related to immune response and growth performance. Cows were dried off 46 d before expected calving and randomly assigned to 1 of 2 treatments: heat stress (HT; n=18) or cooling (CL; n=18). Cows of the CL group were housed with sprinklers, fans and shade, whereas cows of HT group had only shade. After calving, the cows were milked and their colostrum was frozen for the subsequent study. Colostrum from cows exposed to a thermoneutral environment during the dry period was pooled and stored frozen (-20C). Within 4h of birth, 3.8L of the pooled colostrum from thermoneutral cows was fed to calves born to both HT and CL cows. Day of birth was considered study d 0. All calves were exposed to the same management and weaned at d 49. Blood samples were collected before colostrum feeding, 24h after birth and twice weekly up to d 28. Total serum IgG concentrations were determined. Body weight was recorded at birth and at d 15, 30, 45, and 60. Relative to CL calves, HT calves were lighter at birth (38.3 vs. 43.1kg), but no difference in weight gain was observed at d 60. Additionally, HT calves had lower apparent efficiency of IgG absorption (26.0 vs. 30.2%), but no differences were observed for total IgG concentration. The objective of the second study was to evaluate the isolated effect of the colostrum from HT cows on calf immune response and growth performance. The experimental design was identical to the first study, but all calves were born to cows under thermoneutral conditions during the dry period. At birth, calves were blocked by sex and birth weight and then randomly assigned to 1 of 2 treatments, which meant they received pooled colostrum from HT cows or CL cows. No treatment effect was observed on passive immune transfer or on postnatal growth. Thus, heat stress during the last 6 wk of gestation negatively affects the ability of the calf to acquire passive immunity, regardless of colostrum source. PMID:25108869

Monteiro, A P A; Tao, S; Thompson, I M; Dahl, G E

2014-10-01

144

Predicting milk yield in sheep used for dairying in Australia.  

PubMed

It is necessary to identify traits that are simple to measure and correlated with milk yield to select ewes for dairying from existing populations of sheep in Australia. We studied 217 primiparous and 113 multiparous (second parity, n = 51; third parity, n = 40; and fourth parity, n = 22) East Friesian crossbred ewes, for 2 consecutive lactations, that were milked by machine following a period of suckling (24 to 28 d). We measured lamb growth, milk production, milk yield, and residual milk during early lactation (<d 60 of lactation) to test whether milk production during the suckling period or the growth rate of the lamb predicts milk yield. Milk production at weaning, or the amount of residual milk, or both, predict milk yield within lactations. These measures also predict milk yield between lactations. Lambs were weighed at birth and weaning and milk production in ewes was measured using a 4-h milk production test at d 5 of lactation and at weaning. Following weaning, ewes were milked twice daily and milk yield was recorded weekly for 8 wk and once a month thereafter. Milk production (using a 16-h milk production test) and residual milk were measured at weaning, and again 1 wk and 4 wk later. Milk yield to 120 d was correlated (r2 = 0.39) between lactations, and 120-d milk yield (primiparous 82.7 +/- 2.0 L; multiparous 107.1 +/- 4.2 L; second lactation 146 +/- 3.7 L) can be predicted after 4 wk of machine milking using a single measurement of either daily milk yield (primiparous 770 +/- 25 mL/d; multiparous 940 +/- 44 mL/d; second lactation 1,372 +/- 46 mL/d, r2 = 0.60 to 0.65) or daily milk production (primiparous 1,197 +/- 27 mL/d; multiparous 1,396 +/- 62 mL/d; second lactation 1,707 +/- 45 mL/d, r2 = 0.50 to 0.53). Residual milk in primiparous ewes (38%) and multiparous ewes (34%) was high (292 +/- 11 and 321 +/- 20 mL, respectively) in the first lactation, but lower (17%) in the second lactation (238 +/- 17 mL). Residual milk and 120-d milk yield were not correlated in either lactation and we suggest that the transfer of milk from the alveoli to the cistern between each milking may be an important mechanism that maintains milk yield in these ewes. PMID:17954745

Morrissey, A D; Cameron, A W N; Caddy, D J; Tilbrook, A J

2007-11-01

145

Origin of hydrous fluids at seismogenic depth: Constraints from natural and experimental fault rocks  

NASA Astrophysics Data System (ADS)

Fluids control the mechanical behavior of fault zones during the seismic cycle. We used geochemical, mineralogical, microstructural, hydrogen isotope compositions and Fourier Transform Infrared (FTIR) investigations to characterize the origin of hydrous fluids involved in ductile and brittle shear zones at the bottom of the seismogenic crust. Natural samples were collected from exhumed mylonitic shear zones and cataclasite-pseudotachylyte bearing faults in the northern Adamello (Italian Southern Alps), which were active at 9-11 km depth. Pseudotachylytes, solidified coseismic friction-induced melts, testify to ancient seismogenic behavior of the faults. Natural pseudotachylytes were compared with artificial pseudotachylytes produced in high velocity friction experiments simulating seismic slip. Mylonites have mineralogical, elemental and hydrogen isotope compositions (-80D<-60) compositions suggesting interactions with a crustal metamorphic fluid. Pseudotachylytes are composed of high temperature minerals (plagioclase, biotite, dmisteinbergite, cordierite, and scapolite) and have elemental compositions resulting from mixing of tonalite and cataclasite. Pseudotachylytes have complex microstructures, including: (i) microlitic domains, with well crystallized micrometric biotite, which have hydrogen isotope composition (-8150 C and have low ?D value (-93). The hydrogen isotope composition of bulk samples is dominated by the composition of cryptocrystalline domains (-103

Mittempergher, Silvia; Dallai, Luigi; Pennacchioni, Giorgio; Renard, Franois; Di Toro, Giulio

2014-01-01

146

Effects of rubber flooring during the first 2 lactations on production, locomotion, hoof health, immune functions, and stress.  

PubMed

Some housing systems on dairy farms can result in long-term chronic pain. The effects of acute pain on immunity have been explored, but chronic pain's influence on immune responses is still poorly understood. Therefore, the objective of this research was to determine chronic effects of flooring on immune responses and production in freestall housing for dairy cows. Thirty heifers were studied from before calving as first-calf heifers until d 180 of their second lactation. Treatments were rubber (Kraiburg; Agromatic Inc., Fond du Lac, WI) flooring or concrete with diamond grooves in a freestall barn, each in 2 quadrants of the barn. Heifers entered the treatments after calving, so the system was dynamic and each cow was considered an experimental unit. At the end of the first lactation, cows were housed in a bedded pack barn with pasture access until calving was imminent. At that time, they returned to their assigned treatment, but not necessarily into the same quadrant. Production, reproduction, cortisol, acute-phase proteins, and health data were recorded throughout lactation 1, locomotion was scored weekly, and hoof scoring and care was conducted on d 60 and 180 of lactations 1 and 2, and quantitative real-time-PCR of blood leukocytes was analyzed in mid lactation of lactation 1. Mature-equivalent milk fat, milk protein, and protein percentages during the first lactation were greater for cows on the rubber flooring. Hoof and leg therapy treatments per cow were fewer for rubber floor-housed cows. Locomotion scores were less for cows housed on rubber during the second lactation. White blood cell counts were less for cows housed on rubber, and caused by greater lymphocyte counts for cows housed on concrete. The possibility of chronic inflammation was substantiated by less IL-1? and more IL-1 receptor antagonists for cows housed on rubber at d 150 in the second lactation. Cortisol and acute-phase proteins did not differ between the treatments. Interferon-?, IL-12, the modulator of tissue reconstruction (B-cell-transforming growth factor 1), and pain-modulating neurokinin (tachykinin 1) were not different at d 105. These data show indicators of chronic inflammation for cows housed on the concrete flooring compared with those housed on rubber. Implications for the use of rubber flooring in freestall barns are broader than just lameness and may affect many aspects of cow physiology and production. PMID:23587383

Eicher, S D; Lay, D C; Arthington, J D; Schutz, M M

2013-06-01

147

Factors affecting carcass value and profitability in early-weaned Simmental steers: II. Days on feed endpoints and sorting strategies.  

PubMed

In a 4-yr study, early-weaned Simmental steers (n = 192) of known genetics were individually fed to determine EPD, performance, and carcass measurements explaining variation in carcass value and profitability across incremental days on feed (DOF) when sorted by HCW, calculated yield grade (YG), or at their highest profit endpoint (BEST). Steers were weaned at 88.0 +/- 1.1 d of age, pen-fed a high-concentrate diet for 84.5 +/- 0.4 d, individually fed for 249.7 +/- 0.7 d, and slaughtered at 423.3 +/- 1.4 d of age. Carcass weight, YG, and marbling score (MS) were predicted using real-time ultrasound throughout the finishing period to calculate carcass value and profitability at 90, 60, 30 d preslaughter and under three individual sorting strategies. Sorting strategies included marketing the 25 and 50% heaviest HCW, the highest YG at d 60 and 30, or the remaining 25% at 0-d endpoints. Independent variables were year, weaning weight EPD, yearling weight EPD, marbling EPD, DMI, ADG, HCW, YG, and MS. Profit was quadratic in response to increased DOF; the greatest economic return was noted on d 30 (pre-slaughter). Final weight, DMI, HCW, MS, and YG increased (linear; P < 0.001) with additional DOF, and ADG and G:F decreased (linear; P < 0.001). Total cost of gain was quadratic (P < 0.001), and incremental cost of gain rose at an increasing rate (quadratic; P < 0.001) with increased DOF. With increasing DOF, HCW importance decreased from 58 to 21%; MS was variable, ranging from 18 to 23%; and YG and DMI were minor contributors to profit variation. Among sorting strategies, final BW and HCW were greater for BEST, whereas other measurements were similar. Sorting individuals by HCW, YG, or at BEST increased profitability 3.70 dollars, 2.52 dollars, or 30.65 dollars over the optimal group DOF endpoint (d 30). Retrospective analyses illustrated that sorting does not need to pinpoint each animal's profit optimum to result in economic gains; rather, increasing HCW and decreasing weight- and YG-related penalties improved profitability. Opportunities may exist with existing and new technology to uniformly allocate cattle into feeding and marketing groups, decrease overfeeding, and increase carcass value and profitability. PMID:16282633

Pyatt, N A; Berger, L L; Faulkner, D B; Walker, P M; Rodriguez-Zas, S L

2005-12-01

148

A Chandra Perspective on Galaxy-wide X-ray Binary Emission and its Correlation with Star Formation Rate and Stellar Mass: New Results from Luminous Infrared Galaxies  

NASA Astrophysics Data System (ADS)

We present new Chandra observations that complete a sample of seventeen (17) luminous infrared galaxies (LIRGs) with D < 60 Mpc and low Galactic column densities of N H <~ 5 1020 cm-2. The LIRGs in our sample have total infrared (8-1000 ?m) luminosities in the range of L IR? (1-8) 1011 L sun. The high-resolution imaging and X-ray spectral information from our Chandra observations allow us to measure separately X-ray contributions from active galactic nuclei and normal galaxy processes (e.g., X-ray binaries and hot gas). We utilized total infrared plus UV luminosities to estimate star formation rates (SFRs) and K-band luminosities and optical colors to estimate stellar masses (M sstarf) for the sample. Under the assumption that the galaxy-wide 2-10 keV luminosity (L gal HX) traces the combined emission from high-mass X-ray binaries (HMXBs) and low-mass X-ray binaries, and that the power output from these components is linearly correlated with SFR and M sstarf, respectively, we constrain the relation L gal HX = ?M sstarf + ?SFR. To achieve this, we construct a Chandra-based data set composed of our new LIRG sample combined with additional samples of less actively star-forming normal galaxies and more powerful LIRGs and ultraluminous infrared galaxies (ULIRGs) from the literature. Using these data, we measure best-fit values of ? = (9.05 0.37) 1028 erg s-1 M -1 sun and ? = (1.62 0.22) 1039 erg s-1 (M sun yr-1)-1. This scaling provides a more physically meaningful estimate of L gal HX, with ?0.1-0.2 dex less scatter, than a direct linear scaling with SFR. Our results suggest that HMXBs dominate the galaxy-wide X-ray emission for galaxies with SFR/M sstarf gsim5.9 10-11 yr-1, a factor of ?2.9 times lower than previous estimates. We find that several of the most powerful LIRGs and ULIRGs, with SFR/M sstarf >~ 10-9 yr-1, appear to be X-ray underluminous with respect to our best-fit relation. We argue that these galaxies are likely to contain X-ray binaries residing in compact star-forming regions that are buried under thick galactic columns large enough to attenuate emission in the 2-10 keV band (N H >~ 1023 cm-2).

Lehmer, B. D.; Alexander, D. M.; Bauer, F. E.; Brandt, W. N.; Goulding, A. D.; Jenkins, L. P.; Ptak, A.; Roberts, T. P.

2010-11-01

149

Comparison of shortened and conventional dry period management strategies.  

PubMed

The aim of this study was to compare 2 dry-cow management strategies and evaluate the effect of shortened dry period strategy on feed intake, metabolism, and postpartum performance of dairy cows in early lactation. Twenty-nine high-yielding dairy cows were divided into 2 groups. The control (CON) group (n=14) was assigned to a traditional dry period of approximately 60 d (575.9 d) and was fed a far-off dry cow ration from dry-off to -21 d relative to expected parturition. From d -21 relative to expected parturition, the cows were switched to a precalving ration containing an additional 3kg of concentrates. The cows of the experimental group (n=15) were assigned to a shortened dry period (SDP; 356.3 d) and were continuously fed a late-lactation diet from d -60 d relative to expected parturition until calving. After calving, both groups were fed the same lactation diet corresponding to their lactation requirements and cows were followed for 100 d of lactation. Prepartum dry matter intake of the cows assigned to an SDP and fed a late-lactation diet was approximately 4.11kg/cow per day greater compared with the CON group during the 60 d. However, no effect of dry period strategy on postpartum dry matter intake was detected. The cows with an SDP produced approximately 2.78kg/d (6.9%) less milk in the first 100 d of lactation than CON cows; the difference was not statistically significant. No differences were observed in live body weight, body condition score, or back-fat thickness between the treatments. Similarly, no differences existed in concentrations of plasma metabolites. The cows of the SDP group showed lower pH and increased concentrations of lactic acid and volatile fatty acids prepartum than the CON cows. Postpartum concentrations of lactic acid, volatile fatty acids, and NH3 and pH in rumen fluid did not differ between the treatments. Shortening of the dry period did not affect the colostrum quality or birth weights of the calves. Based on the results of this study, a traditional dry period management strategy appeared to be more favorable, considering the dry matter intake and milk production, compared with an SDP and feeding a late-lactation diet throughout the dry period. PMID:24997667

Cermakova, J; Kudrna, V; Simeckova, M; Vyborna, A; Dolezal, P; Illek, J

2014-09-01

150

Zonation of Hydrothermal Alteration in the Central Uplift of the Puchezh-Katunki Astrobleme  

NASA Astrophysics Data System (ADS)

The giant (D = 80 km) Puchezh-Katunki astrobleme [1,2] is the site of widespread hydrothermal alteration. It occurs mainly in the central uplift composed of brecciated archean rocks and overlain by allogenic breccia, suevites, and coptomict gravelites (the latter is the lowest bed of crater-lake deposits). Distribution and vertical zonation of secondary minerals is controlled by the thermal gradient during cooling of authigenic breccia massif, while the degree of alteration depends on the intensity of brecciation and fracturing of basement rocks. Three types of hydrothermal mineralization are distinguished on the basis of different crystallization conditions: (1) mixed hydrothermal-diagenetic, in coptomict gravelites; (2) metasomatic, including formation of Fe-Mg hydrous phyllosilicates in shocked and thermally altered gneisses and amphibolites; and (3) veins, represented by mineral associations filling fractures and voids in basement rocks, allogenic breccia, and suevites. The second and third types occur together and each displays characteristic zonations, thus several zones may be distinguished in vertical section (zones 2-4 below). The uppermost zone corresponds to mixed hydrothermal-diagenetic conditions described in (1) above. In general, four zones are distinguished, from top downward, as follows. 1. Zone of hydrothermal-diagenetic alteration in coptomict gravelites. In this zone, replacement of impact glass fragments by assemblage of montmorillonite, calcite, and pyrite, and formation of alkali zeolites and calcite as a cement are observed establishing a temperature of alteration of less than 100 degrees C. 2. Zone of low-temperature (100 degrees-200 degrees C) mineralization comosed of suevites, allogenic breccia, and the upper part of authigenic breccia down to 2.5 km. Fe-saponite develops in shocked and recrystallized basement rocks, and various zeolites, apophylite, calcite, anhydrite, and pyrite fill vugs and fractures; in addition, calcite-nontronite veinlets occur locally. The distribution of zeolites is characterized by their own zonation [3]. 3. Zone of moderate-temperature (200 degrees-300 degrees C) mineralization in basement at a depth of 2.5-4.2 km. Chlorite (of diabantite-pictochlorite series) is a common metasomatic phase associated with pyrite, and also with albite, epidote, and calcite locally. In veinlets, Ca-Fe silicates (andradite, salite, epidote, prehnite) together with pyrite, chlorite, and, very rarely, quartz, are found in a laumontite-anhydrite matrix. 4. Zone of low-moderate-temperature (150 degrees - 250 degrees C?) mineralization at a depth below 4.2 km. Prehnite, anhydrite, calcite, and pyrite are present. Absence of Ca-Fe silicates may indicate a decrease in crystallization temperature compared with the upper zone, while disappearance of hydrous phases seems to be a result of the fall of P(sub)H2O at this depth. The decrease in degree of alteration outward from the impact center and the change in zeolite composition to lower-temperature varieties as well as crystallization of gypsum instead of anhydrite are evidence of lateral hydrothermal zonation in the crater. Thus the zones may have an ellipsoidal shape corresponding to isotherms during circulation. The generalized chronological order of hydrothermal crystallization is the following: Ca-Fe silicates, chlorite (smectites)-calcite, pyrite-anhydrite- zeolites, apophyllite-calcite, nontronite. This reflects a continually decreasing temperature during the process of hydrothermal alteration. Spatial segregation of minerals is caused by change of parameters (pH, f(sub)CO2, temperature, etc.) of solutions moving in the thermogradient field, where the source of heat is a result of the thermal history of the central uplift [4]. Nevertheless, the role of endogenic heat and mass transfer in impact-induced hydrothermal circulation processes cannot be ruled out. References: [1] Masaitis V. L. and Mashchak M. S. (1990) Meteoritics, 25, 383a. [2] Pevzner L. A. et al. (1992) LPS XXIII, 1063-1064. [3] Naumov M. V. (1992) LPS XXIII, 967-968. [4] M

Naumov, M. V.

1993-07-01

151

Effects of chronic heat stress on plasma concentration of secreted heat shock protein 70 in growing feedlot cattle.  

PubMed

Sixty Angus steers (449.211.0 kg) with implanted body temperature (BT) transmitters were used in a 110-d study to determine the effect of chronic stress (housing, diet, and climate) on extracellular heat shock protein 70 (eHsp70) concentration in plasma. The steers were a subset of a larger study involving 164 steers. Before the start of the study (d -31), 63 steers were implanted with a BT transmitter between the internal abdominal muscle and the peritoneum at the right side flank. Steers were housed in 20 pens (10 with shade and 10 without). Within each pen, 3 steers had a transmitter, and BT was recorded at 30-min intervals throughout the study. On d 0, 30, 60, 90, and 110, steers were weighed, BCS assessed (1 to 9 scale in which 1=emaciated and 9=obese), and 10 mL of blood from the coccygeal vein was collected for determination of inducible heat shock protein 70 (Hsp70) concentration by ELISA. Climatic variables (ambient temperature, relative humidity, solar radiation, black globe temperature, and wind speed) were obtained every 30 min from an on-site weather station. The relationship between the climatic variables and Hsp70 concentration were examined. As we failed to detect an effect of shade, all data were pooled. Mean BT over the duration of the study was 39.60.10C. Mean BT was lowest (38.70.10C) on d 0 and highest on d 110 (40.2C0.10). The Hsp70 concentration was least on d 0 (2.330.47 ng/mL) and greatest on d 30 (8.080.78 ng/mL). The Hsp70 concentration decreased from d 30 but remained above the d-0 concentrations on d 60, 90, and 110. There was a strong relationship between Hsp70 concentration and ambient temperature (r2=0.86; P<0.0001) and Hsp70 concentration and photoperiod (r2=0.94; P<0.0001) and no relationship with BT (r2=0.06; P<0.0001). When assessed with both BCS and BT, the relationship was moderate (r2=0.48; P<0.001). The relationship between Hsp70 and change in BT (BT?) above 38.6C was also moderate (r2=0.54; P<0.0001). The BT at a given time does not appear to be related to Hsp70 concentration. However, Hsp70 expression may be a useful indictor for BT? when BT>38.6C. The Hsp70 concentration is a reliable indicator of chronic stress but is not a reliable indicator of a single stressor when animals are exposed to multiple chronic stressors. PMID:23048154

Gaughan, J B; Bonner, S L; Loxton, I; Mader, T L

2013-01-01

152

Hydrogen Atom Transfer Reactions of a Ruthenium Imidazole Complex: Hydrogen Tunneling and the Applicability of the Marcus Cross Relation  

PubMed Central

The reaction of RuII(acac)2(py-imH) (RuIIimH) with TEMPO (2,2,6,6-tetramethyl-piperidine-1-oxyl radical) in MeCN quantitatively gives RuIII(acac)2(py-im) (RuIIIim) and the hydroxylamine TEMPO-H by transfer of H (H+ + e?) (acac = 2,4-pentanedionato, py-imH = 2-(2?-pyridyl)imidazole). Kinetic measurements of this reaction by UV-vis stopped-flow techniques indicate a bimolecular rate constant k3H = 1400 100 M?1 s?1 at 298 K. The reaction proceeds via a concerted hydrogen atom transfer (HAT) mechanism, as shown by ruling out the stepwise pathways of initial proton or electron transfer due to their very unfavorable thermochemistry (?G). Deuterium transfer from RuII(acac)2(py-imD) (RuIIimD) to TEMPO is surprisingly much slower at k3D = 60 7 M?1 s?1, with k3H/k3D = 23 3 at 298 K. Temperature dependent measurements of this deuterium kinetic isotope effect (KIE) show a large difference between the apparent activation energies, Ea3D ? Ea3H = 1.9 0.8 kcal mol?1. The large k3H/k3D and ?Ea values appear to be greater than the semi-classical limits and thus suggest a tunneling mechanism. The self-exchange HAT reaction between RuIIimH and RuIIIim, measured by 1H NMR line broadening, occurs with k4H = (3.2 0.3) 105 M?1 s?1 at 298 K and k4H/k4D = 1.5 0.2. Despite the small KIE, tunneling is suggested by the ratio of Arrhenius pre-exponential factors, log(A4H/A4D) = ?0.5 0.3. These data provide a test of the applicability of the Marcus cross relation for H and D transfers, over a range of temperatures, for a reaction that involves substantial tunneling. The cross relation calculates rate constants for RuIIimH(D) + TEMPO that are greater than those observed: k3H,calc/k3H = 31 4 and k3D,calc/k3D = 140 20 at 298 K. In these rate constants and in the activation parameters, there is a better agreement with the Marcus cross relation for H than for D transfer, despite the greater prevalence of tunneling for H. The cross relation does not explicitly include tunneling, so close agreement should not be expected. In light of these results, the strengths and weaknesses of applying the cross relation to HAT reactions are discussed. PMID:18841973

Wu, Adam; Mayer, James M.

2009-01-01

153

DEM generation from digital photographs using computer vision: Accuracy and application  

NASA Astrophysics Data System (ADS)

Data for detailed digital elevation models (DEMs) are usually collected by expensive laser-based techniques, or by photogrammetric methods that require expertise and specialist software. However, recent advances in computer vision research now permit 3D models to be automatically derived from unordered collections of photographs, and offer the potential for significantly cheaper and quicker DEM production. Here, we review the advantages and limitations of this approach and, using imagery of the summit craters of Piton de la Fournaise, compare the precisions obtained with those from formal close range photogrammetry. The surface reconstruction process is based on a combination of structure-from-motion and multi-view stereo algorithms (SfM-MVS). Using multiple photographs of a scene taken from different positions with a consumer-grade camera, dense point clouds (millions of points) can be derived. Processing is carried out by automated 'reconstruction pipeline' software downloadable from the internet. Unlike traditional photogrammetric approaches, the initial reconstruction process does not require the identification of any control points or initial camera calibration and is carried out with little or no operator intervention. However, such reconstructions are initially un-scaled and un-oriented so additional software has been developed to permit georeferencing. Although this step requires the presence of some control points or features within the scene, it does not have the relatively strict image acquisition and control requirements of traditional photogrammetry. For accuracy, and to allow error analysis, georeferencing observations are made within the image set, rather than requiring feature matching within the point cloud. Application of SfM-MVS is demonstrated using images taken from a microlight aircraft over the summit of Piton de la Fournaise volcano (courtesy of B. van Wyk de Vries). 133 images, collected with a Canon EOS D60 and 20 mm fixed focus lens, were used to create a ~1.6 km wide DEM covering the summit craters. When compared with a DEM constructed using close-range photogrammetry the SfM-MVS results showed an RMS error of 1.0 m. The overall precision of the project can be considered by ratioing this against the average viewing distance (1000 m). This relative precision of 1:1000 is in line with the results of other projects carried out over a range of spatial scales (down to ~0.1 m), so appears to be a characteristic expected achievable precision for the SfM-MVS approach. Consequently, over shorter viewing distances, absolute precisions increase - e.g. centimeter-level precisions for outcrop-scale studies where viewing distances may be expected to be of order 10 m. Although SfM-MVS cannot deliver the accuracy and precision of formal close-range photogrammetry, it can approach the results that are achievable from single stereo image pairs. However, the main advantages of the technique lie in the enhanced flexibility in image collection and automated processing, both of which significantly decrease the level of expertise required. When compared with terrestrial laser scanning at outcrop scales, the data collection time in the field can be reduced by ~80%. SfM-MVS data quality is sufficient for the technique to provide valuable DEMs of active flows and domes where access to (or for) modern surveying equipment is restricted.

James, M. R.; Robson, S.

2012-12-01

154

The accuracy of photo-based structure-from-motion DEMs  

NASA Astrophysics Data System (ADS)

Data for detailed digital elevation models (DEMs) are usually collected by expensive laser-based techniques, or by photogrammetric methods that require expertise and specialist software. However, recent advances in computer vision research now permit 3D models to be automatically derived from unordered collections of photographs, offering the potential for significantly cheaper and quicker DEM production. Here, we assess the accuracy of this approach for geomorphological applications using examples from a coastal cliff and a volcanic edifice. The reconstruction process is based on a combination of structure-from-motion and multi-view stereo algorithms (SfM-MVS). Using multiple photographs of a scene taken from different positions with a consumer-grade camera, dense point clouds (millions of points) can be derived. Processing is carried out by automated 'reconstruction pipeline' software downloadable from the internet, e.g. http://blog.neonascent.net/archives/bundler-photogrammetry-package/. Unlike traditional photogrammetric approaches, the initial reconstruction process does not require the identification of any control points or initial camera calibration and is carried out with little or no operator intervention. However, such reconstructions are initally un-scaled and un-oriented so additional software (http://www.lancs.ac.uk/staff/jamesm/software/sfm_georef.htm) has been developed to permit georeferencing. Although this step requires the presence of some control points or features within the scene, it does not have the relatively strict image acquisition and control requirements of traditional photogrammetry. For accuracy, and to allow error analysis, georeferencing observations are made within the image set, rather than requiring feature matching within the point cloud. In our coastal example, 133 photos taken with a Canon EOS 450D and 28 mm prime lens, from viewing distances of ~20 m, were used to reconstruct a ~60 m long section of eroding cliff. The resulting surface model was compared with data collected by a Riegl LMS-Z210ii terrestrial laser scanner. Differences between the surfaces were dominated by the varying effects of occlusions on the techniques, and systematic distortion of the SfM-MVS model along the length of the cliff could not be resolved over the 15 mm precision of the TLS data. For a larger-scale example, a ~1.6 km wide region over the summit of Piton de la Fournaise volcano was reconstructed using 133 photos taken with a Canon EOS D60 and 20 mm prime lens, from a microlight aircraft (with a representative viewing distance of 1.0 km). In this case, the resulting DEM showed an RMS error of 1.0 m when compared with the results from traditional photogrammetry and some areas of systematic error were evident. Such errors were minimised by reprocessing the SfM-MVS results with a more sophisticated camera model than is integrated into the reconstruction pipeline. In combination, the results indicate that, with a good, convergent image set, SfM-MVS can be anticipated to deliver relative precisions of 1:1000 or better, for geomorphological applications. However, under certain conditions, the restricted camera model used can result in detectable error. We highlight the requirement for new network design tools that will help optimise image collection, facilitate error visualisation and allow a user to determine whether their image network is fit for purpose.

James, M. R.; Robson, S.

2012-04-01

155

Effects of energy supplementation frequency and forage quality on performance, reproductive, and physiological responses of replacement beef heifers.  

PubMed

The objective of this study was to compare performance, physiological, and reproductive responses of beef heifers consuming forages differing in nutritional quality and offered a low-starch energy supplement at 2 different frequencies. Forty-eight Brahman British heifers (initial age = 294 3 d) were allocated into 1 of 16 drylot pens (3 heifers/pen) which were randomly assigned to receive, in a 2 2 factorial arrangement of treatments: 1) low-quality hay [LQ; stargrass (Cynodon nlemfuensis) with 8% CP and 81% NDF, DM basis] and daily supplementation (S7); 2) LQ and supplementation 3 times weekly (S3); 3) medium-quality hay [MQ; bermudagrass (C. dactylon) with 12% CP and 74% NDF, DM basis] and S7; and 4) MQ and S3. Throughout the study (d 0 to 120), hay was offered in amounts to ensure ad libitum access, and a supplement based on soybean hulls and wheat middlings was offered at weekly rates of 15.8 and 7.9 kg/heifer (DM basis) for LQ and MQ, respectively. Forage and total DMI were evaluated daily, from d 20 to 26, d 34 to 40, and d 48 to 54. Blood samples were collected weekly for determination of plasma progesterone to evaluate puberty attainment. Blood samples were also collected daily, from d 13 to 16, d 27 to 30, d 41 to 44, and d 55 to 58 for determination of plasma urea nitrogen (PUN), glucose, insulin, IGF-I, and NEFA. On d 60, heifers were reallocated by treatment into 4 paddocks and exposed to Angus bulls (1:12 bull:heifer ratio) until d 120. Date of conception was estimated retrospectively by subtracting gestation length (286 d) from the calving date. Heifers receiving S7 had similar (P = 0.52) ADG compared with S3 heifers (0.27 vs. 0.25 kg/d). Heifers provided S7 had less daily variation in hay DMI and plasma concentrations of glucose, NEFA, and IGF-I compared with S3 cohorts (supplementation frequency day interaction; P < 0.01). Similarly, heifers offered MQ and LQ and receiving S7 had less daily variation in total DMI, energy and protein intake, and plasma concentrations of PUN compared with heifers offered MQ and LQ and receiving S3 (hay quality supplementation frequency day interaction; P < 0.01). Attainment of puberty and pregnancy were hastened in S7 heifers compared with S3 heifers (supplementation frequency week interaction; P < 0.02). Therefore, reproductive development of beef replacement heifers consuming diets based on low- and medium-quality forages are enhanced when low-starch energy supplements are offered daily instead of 3 times weekly. PMID:22266994

Moriel, P; Cooke, R F; Bohnert, D W; Vendramini, J M B; Arthington, J D

2012-07-01

156

Long-term performance of visual and electronic identification devices in dairy goats.  

PubMed

Dairy goat kids born during a 3-yr period (n = 97) and their mothers (n = 29) were used for a long-term evaluation of the performance of 9 types of identification (ID) devices. Kids wore multiple ID devices: visual ear tags (V1, tip-tag, n = 47; V2, official, n = 50), electronic ear tags (E1, button-button, n = 46; E2, flag-button, n = 46), electronic rumen boluses (B1, mini-bolus 14 g, n = 92; B2, mini-bolus 20 g, n = 28; B3, standard bolus 75 g, n = 34) and glass-encapsulated transponders injected in the forefeet (T1, 15 mm, n = 75; T2, 12 mm, n = 100). Visual ear tags were applied at birth and removed in yearlings, whereas electronic ear tags were applied after bolusing with B1 (6.7 kg BW and 30 d, on average); B2 were administered in the event of a B1 loss, and B3 in case of a B2 loss and in goat does. At d 60 of age, kids were allocated into 2 groups to evaluate the effects of rearing system on ID. Treatments were: weaned (n = 46), and not weaned (n = 46) where kids suckled a milk substitute until d 150. Readability of ID devices (read/readable x 100) was monitored from 1 to 3 yr of age, depending on device and year of birth. Long-term readability was analyzed using a nonparametric survival analysis. A total of 3.3% infections and 6.5% tissue reactions were reported for electronic ear tags, but ears were fully healed in yearlings. Weaning numerically reduced B1 losses at d 150 (weaned, 84.8% vs. not weaned, 73.3%). Readability of visual ear tags in yearlings (V1, 82.9%; V2, 94.0%) was lower than for electronic ear tags (E1 and E2, 100%). Mini-bolus readability in yearlings did not differ by type (B1, 71.4%; B2, 84.6%) or with visual ear tags. No effect of inject type was reported (T1, 92.0%; T2, 96.0%). Survival analysis after yr 3 gave the greatest readability value for E1 (100%), which did not differ from B3 (96.8%). The lowest readability was estimated for B1 (66.3%), followed by E2 (79.8%), B2 (81.4%), and T1 (90.4%). In conclusion, button-button electronic ear tags and standard boluses were the more efficient devices under our conditions, their readability values being greater than injects, electronic mini-boluses, and visual and flag-button electronic ear tags. Transponders injected in the forefeet and mini-boluses used here are not recommended in practice. Further research on E1 and B3 electronic devices should be done in a higher number of goats to confirm the current results. PMID:19307631

Carn, S; Caja, G; Ghirardi, J J; Salama, A A K

2009-04-01

157

Mexican Infrared-Optical New Technology Telescope: The TIM project  

NASA Astrophysics Data System (ADS)

The scientific goals for TIM are an image quality of 0.25", consistent with the seeing at our site, optimization for the infrared as many scientific programs are going in that region of the spectrum, a M1 diameter in excess of 6.5 meters and a field of view limited to 10 arc minutes. Practical reasons, such as the limited funding available and the requirement of mexican financial agencies that the telescope should be built and installed in Mexico, lead us to decide for a segmented telescope, with a single secondary mirror, a single cassegrain focus and a light high stifness tubular structure. ALthough we are still working on the conceptual design of the telescope, there are some concepts that we are pursuing. The optical desing (M1+M2) is Ritchey-Cretien type with an hyperbolic primary 7.8 m od F/1.5 and a 0.9 m diameter f/15 secondary mirror. This will give a plate scale of 1.7 "/mm. This is 0.03 "/pix in direct mode, enough for AO goals. As for direct imaging, a factor of 5 reduction with 20 cm diam optical components would be able to produce 5' fields on a 2048, 20 microns type detector with 0.17"/pix. This implies that, with the use of auxiliary optics which is a common need for each particular instrument anyway, a wide variety of needs can be accomodated with a single secondary mirror. Choping for infrared observations would however introduce a additional cost in the secondary mirror. Alternatively the use of cold tertiary choping mirror is currently under study. The M1+M2 design currently aquires d80 of 0.17" in a 5' field without correction and 1" in a 10' field, that would require a field correcting lens. The M1 mirror will be segmented into 19 1.8 m diameter segments. There are 4 kinds of segments, the central, which we have kept to provide a reference for phasing, 6 more segments for the first ring and 12 in the outer ring, of two different kinds. The spacing between the segments is 5 mm, enough to reduce the inter-segment thermal background to half a percent of a 99\\% reflectivity primary mirror. The width of the segments was decided to be 7.5 cm, similar to keck's, noting also that the self weight deflections of this segment are sligthly inferior (more rigid) than the NTT mirror as defined by Willson et al. Due to this increased rigidity, and to a more homogeneous distribution, while the NTT mirror is supported in 78 points, the Keck segments are supported by 36. We have decreased this number of support points to 19 in our design, but using extended actuators (airbags) that distribute the support force and that together support most of the area of the segment. The current design allows also the inclusion of wind buffeting actuators, and position actuators at the edges of each segment. Position control of each segment is accomplished by electromechanical and piezo actuators, that thanks to the force actuators, only have to act on a reduced portion of the weigth of each segment. The hard points can be located at the edge of the segment and provide common reference for neighboor segments as well. The telescope structure is being designed by finite element analysis. It is an alt-az mount with cassegrain focus instruments only. The structure is being designed as a high stiffnes, low weigth tubular structure. The upper tube is a two tier design with eigen-frequencies larger than 12.9 Htz. The elevation ring is also being designed as a tubular structure obtaining so far eigen-frecuencies of 12.6. In the combined structure the first eigenfrequency goes down to 8 Hz, but it is a rigid rotation about the elevation axis, and so it is not structural. The second eigenfrequency is a bending of the secondary structure at 8.5 hz, and other designs of the secondary vanes are being sttudied to increment this frequency. The third eigenfrequency is the first real eigen-frequency of the structure and occurs at 13hz. Maximum deflections by gravity are 2.2 mm for the telescope tube at horizon while at zenith its only of 0.7mm. The total weigth of the structure, optics and a few instruments is expected

Salas, L.

1998-11-01