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1.
Geophys Res Lett ; 46(20): 10959-10966, 2019 Oct 28.
Article in English | MEDLINE | ID: mdl-31894168

ABSTRACT

The Jovian polar regions produce X-rays that are characteristic of very energetic oxygen and sulfur that become highly charged on precipitating into Jupiter's upper atmosphere. Juno has traversed the polar regions above where these energetic ions are expected to be precipitating revealing a complex composition and energy structure. Energetic ions are likely to drive the characteristic X-rays observed at Jupiter (Haggerty et al., 2017, https://doi.org/10.1002/2017GL072866; Houston et al., 2018, https://doi.org/10.1002/2017JA024872; Kharchenko et al., 2006, https://doi.org/10.1029/2006GL026039). Motivated by the science of X-ray generation, we describe here Juno Jupiter Energetic Particle Detector Instrument (JEDI) measurements of ions above 1 MeV and demonstrate the capability of measuring oxygen and sulfur ions with energies up to 100 MeV. We detail the process of retrieving ion fluxes from pulse width data on instruments like JEDI (called "puck's"; Clark, Cohen, et al., 2016, https://doi.org/10.1002/2017GL074366; Clark, Mauk, et al., 2016, https://doi.org/10.1002/2015JA022257; Mauk et al., 2013, https://doi.org/10.1007/s11214-013-0025-3) as well as details on retrieving very energetic particles (>20 MeV) above which the pulse width also saturates.

2.
J Geophys Res Space Phys ; 121(8): 7900-7913, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27867799

ABSTRACT

Energetic charged particle detectors characterize a portion of the plasma distribution function that plays critical roles in some physical processes, from carrying the currents in planetary ring currents to weathering the surfaces of planetary objects. For several low-resource missions in the past, the need was recognized for a low-resource but highly capable, mass-species-discriminating energetic particle sensor that could also obtain angular distributions without motors or mechanical articulation. This need led to the development of a compact Energetic Particle Detector (EPD), known as the "Puck" EPD (short for hockey puck), that is capable of determining the flux, angular distribution, and composition of incident ions between an energy range of ~10 keV to several MeV. This sensor makes simultaneous angular measurements of electron fluxes from the tens of keV to about 1 MeV. The same measurements can be extended down to approximately 1 keV/nucleon, with some composition ambiguity. These sensors have a proven flight heritage record that includes missions such as MErcury Surface, Space ENvironment, GEochemistry, and Ranging and New Horizons, with multiple sensors on each of Juno, Van Allen Probes, and Magnetospheric Multiscale. In this review paper we discuss the Puck EPD design, its heritage, unexpected results from these past missions and future advancements. We also discuss high-voltage anomalies that are thought to be associated with the use of curved foils, which is a new foil manufacturing processes utilized on recent Puck EPD designs. Finally, we discuss the important role Puck EPDs can potentially play in upcoming missions.

3.
Brain Res ; 1527: 222-9, 2013 Aug 21.
Article in English | MEDLINE | ID: mdl-23806779

ABSTRACT

BACKGROUND: Early treatment of spinal cord white matter injury has been found beneficial. H2S, a neurotransmitter is neuroprotective at lower doses. PURPOSE: In the present study the effect of NaHS after clip compression injury of spinal cord white matter in vivo was studied. METHODS: The injury was induced in 8-10 weeks old Wistar rats by exposing the spinal cord at T8-T10 level by laminectomy and applying 35 g clip for 1 min. A dose of 50 µM NaHS was given intraperitoneally after 1h of injury. 0.5mm Spinal cord tissues were collected 8h after injury from both sides including epicenter and dorsal column was microdissected and used for further study. RESULTS: NaHS treatment decreases nitric oxide (NO) by 27% and lipid peroxide (LPO) by 18% as compared to injury, which are hallmark of attenuation in oxidative stress. Western blots shows significant changes in Myeloperoxidase (MPO) level went down by 10%. GSH contents increased 44% in treated group as compared to the injury group. NaHS treatment increased Nrf-2 expression 1.8 times. We found NaHS treatment reduced the GFAP expression 8%, there was no significant changes in NF-200 after treatment and no evident morphological changes with H and E staining. CONCLUSIONS: With the above data we conclude that NaHS at 50 µM dose at 1h after injury reduces the NO, LPO, GFAP and MPO level at injury site by increasing the expression of Nrf-2. We expect that a decrease in these parameters during acute phase of spinal cord injury would be helpful in neuroprotection and regeneration.


Subject(s)
Neuroprotective Agents/pharmacology , Oxidative Stress/drug effects , Spinal Cord Compression/metabolism , Sulfides/pharmacology , Animals , Antioxidants/pharmacology , Blotting, Western , Disease Models, Animal , Fluorescent Antibody Technique , Lipid Peroxidation/drug effects , Male , Rats , Rats, Wistar , Spinal Cord Compression/pathology
4.
PLoS One ; 6(12): e29166, 2011.
Article in English | MEDLINE | ID: mdl-22216196

ABSTRACT

Mature microRNAs (miRNAs), derived through cleavage of pre-miRNAs by the Dicer1 enzyme, regulate protein expression in many cell-types including cells in the pancreatic islets of Langerhans. To investigate the importance of miRNAs in mouse insulin secreting ß-cells, we have generated mice with a ß-cells specific disruption of the Dicer1 gene using the Cre-lox system controlled by the rat insulin promoter (RIP). In contrast to their normoglycaemic control littermates (RIP-Cre(+/-) Dicer1(Δ/wt)), RIP-Cre(+/-)Dicer1(flox/flox) mice (RIP-Cre Dicer1(Δ/Δ)) developed progressive hyperglycaemia and full-blown diabetes mellitus in adulthood that recapitulated the natural history of the spontaneous disease in mice. Reduced insulin gene expression and concomitant reduced insulin secretion preceded the hyperglycaemic state and diabetes development. Immunohistochemical, flow cytometric and ultrastructural analyses revealed altered islet morphology, marked decreased ß-cell mass, reduced numbers of granules within the ß-cells and reduced granule docking in adult RIP-Cre Dicer1(Δ/Δ) mice. ß-cell specific Dicer1 deletion did not appear to disrupt fetal and neonatal ß-cell development as 2-week old RIP-Cre Dicer1(Δ/Δ) mice showed ultrastructurally normal ß-cells and intact insulin secretion. In conclusion, we have demonstrated that a ß-cell specific disruption of the miRNAs network, although allowing for apparently normal ß-cell development, leads to progressive impairment of insulin secretion, glucose homeostasis and diabetes development.


Subject(s)
DEAD-box RNA Helicases/genetics , Diabetes Mellitus, Experimental/physiopathology , Gene Deletion , Insulin/metabolism , Islets of Langerhans/metabolism , Ribonuclease III/genetics , Animals , Apoptosis , Blood Glucose/metabolism , Cell Proliferation , Diabetes Mellitus, Experimental/genetics , Flow Cytometry , Gene Knockdown Techniques , Homeostasis , Immunohistochemistry , Insulin Secretion , Islets of Langerhans/pathology , Islets of Langerhans/ultrastructure , Mice
5.
Phys Rev Lett ; 99(8): 081803, 2007 Aug 24.
Article in English | MEDLINE | ID: mdl-17930940

ABSTRACT

This Letter is the first report of the K{L}-->pi{+/-}e{-/+}nue{+}e{-} decay. Based on 19 208+/-144 events, we determine the branching fraction, B(K{L}-->pi{+/-}e{-/+}nue{+}e{-}M_{e{+}e{-}}>5 MeV/c{2},E{e{+}e{-}}{*}>30 MeV)=(1.285+/-0.041)x10{-5}, and Gamma(K{e3ee}M{e{+}e{-}}>5 MeV/c{2})/Gamma(K{e3})=[4.57+/-0.04(stat)+/-0.14(syst)]x10{-5}. This ratio agrees with a theoretical prediction based on chiral perturbation theory (ChPT) calculated to O(p{4}). The measured kinematical distributions agree with those predicted by just ChPT O(p{4}), but show significant disagreement with ones predicted by leading-order ChPT.

6.
Phys Rev Lett ; 96(24): 242001, 2006 Jun 23.
Article in English | MEDLINE | ID: mdl-16907231

ABSTRACT

The asymmetry in the rho angular distribution in the sequential decay Omega+-->LamdaKappa+-->rhopi+Kappa+. has been measured to be alphaOmegaalphaLamda=[+1.16+/-0.18(stat)+/-0.17(syst)]x10(-2) using 1.89x10(6) unpolarized Omega+ decays recorded by the HyperCP (E871) experiment at Fermilab. Using the known value of alphaLamda, and assuming that alphaLamda=-alphaLamda, alphaOmega=[-1.81+/-0.28(stat)+/-0.26(syst)]x10(-2). A comparison between this measurement of alphaOmegaalphaLamda and recent measurements of alphaOmegaalphaLamda made by HyperCP shows no evidence of a violation of CP symmetry.

7.
Phys Rev Lett ; 96(10): 101801, 2006 Mar 17.
Article in English | MEDLINE | ID: mdl-16605723

ABSTRACT

Using the complete KTeV data set of 5,241 candidate K(L)--> pi(+) pi(-) e(+) e(-) decays (including an estimated background of 204 +/- 14 events), we have measured the coupling g(CR)= 0.163 +/- 0.0149(stat) +/- 0.023(syst) of the CP conserving charge radius process and from it determined a K(0) charge radius of = [-0.077 +/- 0.007(stat) +/- 0.011(syst)]fm(2). We have determined a first experimental upper limit of 0.04 (90% C.L.) /g(e1)/ / /g(M1)/ of the couplings for the E1 and M1 direct photon emission processes. We also report the measurement of /g(M1)/ including a vector form factor /g(M1)/(1 + (a(1)/a(2))/((M(2)(p)-(M(2)(k))= 2M(K)E(gamma*)), where vector /g(M1)/= 1.11+/- 0.12(stat) +/- 0.08(syst) and a(1)/a(2) = [-0.744 +/- 0.027(stat) +/- 0.032(syst)] GeV(2)/c(2). Finally, a CP-violating asymmetry of [13.6 +/- 1.4(stat) +/- 1.5(syst)]% in the CP and T odd angle phi between the decay planes of the e(+) e(-) and pi(+) pi(-) pairs in the K(L) center of mass is reported.

8.
Gene Expr Patterns ; 6(5): 448-61, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16458083

ABSTRACT

Anaplastic Lymphoma Kinase (ALK), a receptor tyrosine kinase, was first described as the fusion product causing a subtype of non-Hodgkin's lymphoma. To date Alk has been reported to be mainly expressed in CNS and other parts of the brain. Here we describe an extensive characterization of the mRNA and protein expression of ALK during mouse development. We show that mRNA and ALK protein show overlapping expressing patterns in specific regions of the central and the peripheral nervous systems. Furthermore, ALK is also expressed in the eye, nasal epithelium, olfactory nerve, tongue, skin, tissue surrounding the esophagus, stomach and midgut but not the hindgut. Expression of ALK is also found in testis and ovary.


Subject(s)
Protein-Tyrosine Kinases/genetics , Anaplastic Lymphoma Kinase , Animals , Antibody Specificity , Base Sequence , DNA Primers , Gene Expression Regulation, Developmental , Immunohistochemistry , In Situ Hybridization , Mice , Protein-Tyrosine Kinases/immunology , Protein-Tyrosine Kinases/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Receptor Protein-Tyrosine Kinases
9.
Phys Rev Lett ; 95(8): 081801, 2005 Aug 19.
Article in English | MEDLINE | ID: mdl-16196851

ABSTRACT

The xi0 muon semileptonic decay has been observed for the first time with nine identified events using the KTeV beam line and detector at Fermilab. The decay is normalized to the xi0 beta decay mode and yields a value for the ratio of decay rates gamma(xi0 --> sigma+ mu- nu(mu))/gamma(xi0 --> sigma+ e- nu(e)) of [1.8(-0.5)(+0.7)(stat) +/- 0.2(syst)] x 10(-2). This is in agreement with the SU(3) flavor symmetric quark model.

10.
Phys Rev Lett ; 94(18): 181801, 2005 May 13.
Article in English | MEDLINE | ID: mdl-15904358

ABSTRACT

A sensitive search for the lepton-number-violating decay Xi(-)-->pmu(-)mu(-) has been performed using a sample of approximately 10(9) Xi(-) hyperons produced in 800 GeV/c p-Cu collisions. We obtain B(Xi(-)-->pmu(-)mu(-))<4.0x10(-8) at 90% confidence, improving on the best previous limit by 4 orders of magnitude.

11.
Phys Rev Lett ; 94(10): 101804, 2005 Mar 18.
Article in English | MEDLINE | ID: mdl-15783474

ABSTRACT

A sensitive search for the rare decays Omega(-)--> Lambdapi(-) and Xi(0)--> ppi(-) has been performed using data from the 1997 run of the HyperCP (Fermilab E871) experiment. Limits on other such processes do not exclude the possibility of observable rates for |DeltaS| = 2 nonleptonic hyperon decays, provided the decays occur through parity-odd operators. We obtain the branching-fraction limits B(Omega(-)-->Lambdapi(-)) < 2.9 x 10(-6) and B(Xi(0)--> ppi(-)) < 8.2 x 10(-6), both at 90% confidence level.

12.
Dev Dyn ; 232(4): 1105-14, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15739225

ABSTRACT

The A Disintegrin And Metalloprotease (ADAM) family of metalloproteases affects a variety of proteins with important roles in development and disease, including growth factors and adhesion molecules. We have analyzed the expression patterns of ADAMs 9, 10, and 17 during pancreas ontogeny. All ADAMs investigated were expressed in the pancreatic anlagen but invariably became restricted to divergent pancreatic compartments. ADAM9 and 17 became restricted to the insulin-producing beta-cells and all islet cells, respectively. During embryogenesis, ADAM10 was detected predominantly in acinar cells, but in the adult, it was localized to the cell surface membrane of both endocrine and exocrine cells. In addition to ADAM9, a potential prognostic factor for ductal cancers, we describe the expression of ADAM10 and ADAM17 in the pancreatic ductal epithelium. Altogether, the dynamic expression profile of the ADAM proteases described here may reflect a functional divergence of these as mediators of pancreas biology.


Subject(s)
Gene Expression Regulation, Developmental/physiology , Islets of Langerhans/embryology , Metalloendopeptidases/biosynthesis , Animals , Female , Islets of Langerhans/cytology , Male , Mice , Mice, Inbred CBA , Organ Specificity/physiology
13.
Phys Rev Lett ; 94(2): 021801, 2005 Jan 21.
Article in English | MEDLINE | ID: mdl-15698162

ABSTRACT

We report the first evidence for the decay Sigma(+)-->pmu(+)mu(-) from data taken by the HyperCP (E871) experiment at Fermilab. Based on three observed events, the branching ratio is B(Sigma(+)-->pmu(+)mu(-))=[8.6(+6.6)(-5.4)(stat)+/-5.5(syst)]x10(-8). The narrow range of dimuon masses may indicate that the decay proceeds via a neutral intermediate state, Sigma(+)-->pP(0),P0-->mu(+)mu(-) with a P0 mass of 214.3+/-0.5 MeV/c(2) and branching ratio B(Sigma(+)-->pP(0),P0-->mu(+)mu(-))=[3.1(+2.4)(-1.9)(stat)+/-1.5(syst)]x10(-8).

14.
Phys Rev Lett ; 93(18): 181802, 2004 Oct 29.
Article in English | MEDLINE | ID: mdl-15525151

ABSTRACT

We present a determination of the Cabibbo-Kobayashi-Maskawa parameter |V(us)| based on new measurements of the six largest K(L) branching fractions and semileptonic form factors by the KTeV (E832) experiment at Fermilab. We find |V(us)|=0.2252+/-0.0008(KTeV)+/-0.0021(ext), where the errors are from KTeV measurements and from external sources. We also use the measured branching fractions to determine the CP violation parameter |eta(+-)|=(2.228+/-0.005(KTeV)+/-0.009(ext))x10(-3).

15.
Phys Rev Lett ; 93(2): 021805, 2004 Jul 09.
Article in English | MEDLINE | ID: mdl-15323902

ABSTRACT

The KTeV/E799 experiment at Fermilab has searched for the rare kaon decay K(L)-->pi(0)e(+)e(-). This mode is expected to have a significant CP violating component. The measurement of its branching ratio could support the standard model or could indicate the existence of new physics. This Letter reports new results from the 1999-2000 data set. One event is observed with an expected background at 0.99+/-0.35 events. We set a limit on the branching ratio of 3.5x10(-10) at the 90% confidence level. Combining with the previous result based on the data set taken in 1997 yields the final KTeV result: BR(K(L)-->pi(0)e(+)e(-))<2.8x10(-10) at 90% C.L.

16.
Phys Rev Lett ; 93(26 Pt 1): 262001, 2004 Dec 31.
Article in English | MEDLINE | ID: mdl-15697968

ABSTRACT

We have compared the p and p angular distributions in 117 x 10(6) Xi- -->Lambdapi- -->ppi-pi- and 41 x 10(6) Xi+ -->Lambda pi+ -->p pi+pi+ decays using a subset of the data from the HyperCP experiment (E871) at Fermilab. We find no evidence of CP violation, with the direct-CP-violating parameter AXiLambda identical with (alphaXialphaLambda-alpha Xialpha Lambda)/(alphaXialphaLambda+alphaXialphaLambda)=[0.0+/-5.1(stat)+/-4.4(syst)] x 10(-4).

17.
Phys Rev Lett ; 90(14): 141801, 2003 Apr 11.
Article in English | MEDLINE | ID: mdl-12731905

ABSTRACT

The KTeV experiment at Fermilab has isolated a total of 132 events from the rare decay K(L)-->e+ e- mu+ mu-, with an estimated background of 0.8 events. The branching ratio of this mode is determined to be [2.69+/-0.24(stat)+/-0.12(syst)]x10(-9), with a radiative cutoff of M(2)(ee mu mu)/M(2)(K)>0.95. The first measurement using this mode of the parameter alpha from the D'Ambrosio-Isidori-Portolès (DIP) model of the K(L)gamma*gamma* vertex yields a result of -1.59+/-0.37, consistent with values obtained from other decay modes. Because of the limited statistics, no sensitivity is found to the DIP parameter beta. We use this decay mode to set limits on CP and lepton violation.

18.
Phys Rev Lett ; 89(21): 211801, 2002 Nov 18.
Article in English | MEDLINE | ID: mdl-12443402

ABSTRACT

The recent discovery of a large CP violating asymmetry in KL-->pi+pi-e+e- mode has prompted us to seach for the associated KL-->pi 0 pi 0 e+e- decay mode in the KTeV-E799 experiment at Fermilab. In 2.7 x 10(11) K(L) decays, one candidate event has been observed with an expected background of 0.3 event, resulting in an upper limit for the KL-->pi 0 pi 0 e+e- branching ratio of 6.6 x 10(-9) at the 90% C.L.

19.
Phys Rev Lett ; 89(7): 072001, 2002 Aug 12.
Article in English | MEDLINE | ID: mdl-12190514

ABSTRACT

We use K(L)'s in the 100-200 GeV energy range to produce 147 candidate events of the axial vector pair K1(1270)-K1(1400) in the nuclear Coulomb field of a Pb target and determine the radiative widths Gamma(K1(1400)-->K0+gamma)=280.8+/-23.2(stat)+/-40.4(syst) keV and Gamma(K1(1270)-->K0+gamma)=73.2+/-6.1(stat)+/-28.3(syst) keV. These first measurements appear to be lower than the quark-model predictions. We also place upper limits on the radiative widths for K(*)(1410) and K(*)(2)(1430) and find that the latter is vanishingly small in accord with SU(3) invariance in the naive quark model.

20.
Phys Rev Lett ; 88(18): 181601, 2002 May 06.
Article in English | MEDLINE | ID: mdl-12005674

ABSTRACT

We present a measurement of the charge asymmetry delta(L) in the mode K(L)-->pi(+/-)e(-/+)nu based on 298 x 10(6) analyzed decays. We measure a value of delta(L) = [3322+/-58(stat)+/-47(syst)]x10(-6), in good agreement with previous measurements and 2.4 times more precise than the current best published result. The result is used to place more stringent limits on CPT and DeltaS = DeltaQ violation in the neutral kaon system.

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