Different types of learning and memory functions decrease at different rates in senescence. The present study examines which types of mental functions show a relatively early decline and which ...learning abilities are relatively preserved in late senescence by investigating different types of learning abilities in water maze tests. Two groups of senescent male Wistar rats aged 24 months (group W24) and 30 months (group W30), respectively, were compared to adult rats (12 months, group W12). Group W24 represents ‘senescent’ and group W30 ‘late-senescent’ rats. Whereas acquisition showed a relatively late decline (in group W30), reversal learning was impaired relatively early (group W24).
Radiation damage in undoped CsI and CsI(Tl) Woody, C.L.; Kierstead, J.A.; Levy, P.W. ...
Conference Record of the 1991 IEEE Nuclear Science Symposium and Medical Imaging Conference,
1991
Conference Proceeding
Odprti dostop
Radiation damage has been studied in undoped CsI and CsI(Tl)-crystals using /sup 60/Co gamma radiation for doses up to approximately 4.2*10/sup 6/. Samples from various manufacturers were measured ...ranging in size from 2.54-cm-long cylinders to a 30-cm-long block. Measurements were made on the change in optical transmission and scintillation light output as a function of dose. Although some samples showed a small change in transmission, a significant change in light output was observed for all samples. Recovery from damage was also studied as a function of time and exposure to UV light. A short-lived phosphorescence was observed in undoped CsI, similar to the phosphorescence seen in CsI(Tl).< >
The pathophysiology of bronchopulmonary dysplasia (BPD) as an inflammatory disorder secondary to neonatal respiratory distress syndrome (RDS) is not yet fully understood and still represents a major ...complication of prematurity. The main pathophysiologic feature of RDS is a primary surfactant deficiency in a structurally immature lung. Pulmonary surfactant contains 90 percent phospholipids and 10 percent proteins (surfactant proteins A, B, C, and D). As surfactant protein A (SP-A) has several major immunological and metabolic intrapulmonary functions, we aimed at investigating an association of polymorphisms of SP-A1 and SP-A2 encoding genes and the risk of BPD. We performed a case-control study exclusively including Caucasian preterm infants below 32 weeks of gestation matched for the degree of immaturity and the year of birth. Venous cord blood was taken prospectively and analyzed by polymerase chain reaction (PCR), single-strand conformation polymorphism (SSCP), cloning and sequencing. BPD was defined as oxygen dependency or need for mechanical ventilation at day 28. Twenty-three infants with BPD were enrolled (mean gestational age 26.2 weeks; mean birth weight 760.4 g) and compared with 23 infants matched on the basis of gestational age (mean gestational age 27.9 weeks; mean birthweight 1015 g). We observed a significantly increased frequency of the SP-A1 polymorphism 6A6 in infants with BPD compared with controls. In addition to previously established risk factors for BPD, 6A6 polymorphism for SP-A1 gene is an independent co-factor. We believe treatment of neonatal RDS should also include stratification according to genetic risk factors.
This article favors a progressive policy and management shift in the establishment and implementation of biosphere reserves (BRs). In the new era of the Anthropocene, BRs will need to pursue the ...implementation of sustainable development goals as their central purpose and interpret them even further toward more integrated and consequent forms of sustainable livelihoods. This means placing people even more in the center of policy and management: they are the pioneers and ambassadors making sustainability real. This also means that we have to change the criteria for designating and managing BRs away from representativeness of landscapes toward an integration of their ecological, social, and economic potentials and set in a framework of genuine sustainability governance.
Phys. Rev. C 99, 044912 (2019) The PHENIX collaboration has measured high-$p_T$ dihadron correlations in
$p$$+$$p$, $p$$+$Al, and $p$$+$Au collisions at $\sqrt{s_{_{NN}}}=200$ GeV. The
correlations ...arise from inter- and intra-jet correlations and thus have
sensitivity to nonperturbative effects in both the initial and final states.
The distributions of $p_{\rm out}$, the transverse momentum component of the
associated hadron perpendicular to the trigger hadron, are sensitive to initial
and final state transverse momenta. These distributions are measured
multi-differentially as a function of $x_E$, the longitudinal momentum fraction
of the associated hadron with respect to the trigger hadron. The near-side
$p_{\rm out}$ widths, sensitive to fragmentation transverse momentum, show no
significant broadening between $p$$+$Au, $p$$+$Al, and $p$$+$$p$. The away-side
nonperturbative $p_{\rm out}$ widths are found to be broadened in $p$$+$Au when
compared to $p$$+$$p$; however, there is no significant broadening in $p$$+$Al
compared to $p$$+$$p$ collisions. The data also suggest that the away-side
$p_{\rm out}$ broadening is a function of $N_{\rm coll}$, the number of binary
nucleon-nucleon collisions, in the interaction. The potential implications of
these results with regard to initial and final state transverse momentum
broadening and energy loss of partons in a nucleus, among other nuclear
effects, are discussed.
We report on the results of tests of FEU115M one inch vacuum phototubes manufactured in Russia. The tubes are 12-stage, fast devices with high gain and low dark current. These photomultiplier tubes ...were developed for the PHENIX EMCal project by members of the PHENIX group at IHEP, Protvino (Russia). We report on investigations of the gain, quantum efficiency, linearity, photocathode uniformity and long-term behavior of these tubes.< >
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