255 research outputs found
On the synthesis, characterization, and magnetization of Ln-M-X (Ln = lanthanide; M = Ti-Cr, Cu, Mo, Pd; X = Al, Ga) intermetallics
The focus of the research presented herein was to grow single crystals of Ln-M-X (Ln = lanthanide; M = Ti-Cr, Cu, Mo, Pd; X = Al, Ga) intermetallic compounds and to characterize their crystal structures and physical properties. Overall, the flux growth technique facilitated a detailed analysis of previously known structure-types (LnM2Al20 (Ln = La, Ce, Pr, Yb; M = Ti, V, Cr), Ln6M4Al43 (Ln = Gd, Yb; M = Cr, Mo), and Yb2Pd3Ga9), as well as the synthesis and characterization of new compounds (LnCrxGa3 (Ln = Ho, Er; x ~ 0.13), YbCr2Al20-xFex (x ~ 0.2), Ln(Cu,Al,Ga)13-x, and Ln2PdGa12 (Ln = Pr, Nd, Sm)). LnCrxGa3 (Ln = Ho, Er) adopt a stuffed variant of the AuCu3 structure-type rather than the related Y4PdGa12 structure-type which is adopted by the latter transition metals. Like the related Ln4MGa12 compounds, both analogues exhibit positive magnetoresistance, with ErCrxGa3 reaching ~25% at H = 9 T. After characterizing a number of LnM2Al20 (Ln = La, Ce, Pr, Yb; M = Ti, V, Cr) compounds, Fe was introduced to determine if it would influence the physical properties and to better understand the stability of the CeCr2Al20 structure-type. Mössbauer spectroscopy results for YbCr2FexAl20-x indicate that Fe atoms occupy two crystallographic sites, and X ray diffraction refinements suggest that the Fe atoms occupy the Al1 and Al2 sites rather than the Cr site. These results are consistent with LnM2Al20 compounds only forming for early transition metals. Single crystals of Yb6M4Al43 are non-magnetic consistent with divalent Yb, which contrasts with previously reports. Gd6M4Al43 (M = Ce, Mo, W) appear to order antiferromagnetically below 20 K with positive Weiss temperatures, suggesting that the magnetic structures of these materials are complex. Single crystals of Ln2PdGa12 order antiferromagnetically at 18, 7.5, and 7.5 K, respectively, and heat capacity measurements indicate that Pr2PdGa12 may be a new Pr containing heavy fermion compound. Single crystal neutron diffraction experiments were successfully carried out on NaZn13 type Ln(Cu,Al,Ga)13-x, including Eu(Cu,Al,Ga)13-x, to understand the site occupancies and disorder, and it was found that Cu partially occupies the 8b site while the 96i site is populated with Al, Cu, and Ga
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Prescribed fire in a ponderosa pine stand in the Blue Mountains, Oregon : relationships among post-fire scolytidae incidence, delayed tree mortality, snag decay dynamics, and woodpecker snag use
Delayed tree mortality is an unpredictable occurrence when prescribed burning is implemented. Fire scorched trees may die as the result of crown scorching, stem charring, root injury, bark beetle attack, or through a combination of these factors. This study examined ponderosa pine mortality and the incidence of two bark beetle species (Dendroctonus brevicomis LeConte and Ips pini Say Coleoptera: Scolytidae) following spring and fall prescribed burning on four replicated ponderosa pine stands. There was a positive linear relationship for total tree mortality and Scolytidae incidence with stem char height. No relationship in total tree mortality or Scolytidae incidence was observed between seasons of burn when accounting for stem char height. The presence of established bark beetle galleries was negatively correlated with external stem charring within destructively sampled ponderosa pines that died following burn application. In a related study, woodpecker use and decay dynamics of ponderosa pines dying post-fire were assessed. Woodpecker bark foraging was closely associated with the presence of bark beetles and woodborers (Coleoptera: Buprestidae and Cerambycidae). There was a positive linear relationship between woodpecker cavity excavation and snag DBH. The probability of a snag possessing a woodpecker cavity was significantly greater if the snag had sustained a broken top. Wood deterioration within destructively sampled ponderosa pine snags was negatively influenced by charring sustained to the bark in comparison to uncharred portions of the tree
Education and Training in Inclusive Welfare States
This working paper analyses opportunities for inclusiveness in the context of the digital transfor-mation. There are fears that digitalisation will create new cleavages in societies, and there will be gaps in skills needed in digital working life. Older workers and immigrants, in particular, are in a vulnerable position. The theoretical approaches of social investment and combined capabilities stress the needs for upskilling. These are identified to develop digital and non-digital skills to cope with the challenges of the digital transformation. We show that it is not enough to develop indi-vidual capabilities. To really improve inclusiveness, combined capabilities are needed, which take into account institutional arrangements and corresponding public services
tert-Butyl (2S)-2-{3-[(R)-bis(tert-butoxycarbonyl)amino]-2-oxopiperidin-1-yl}-3-methylbutanoate1
The title compound, C24H42N2O7, is a chiral lactam-constrained amino acid with a six-membered ring backbone and isopropyl and tert-butyl ester side chains. The conformation of the six-membered ring can be described as a half chair, with two CH2 C atoms lying 0.443 (1) and −0.310 (1) Å out of the best plane of the other four atoms (mean deviation = 0.042 Å). Both N atoms are sp
2 hybridized, lying 0.0413 (9) and 0.067 (1) Å out of the planes defined by the three C atoms bonded to them. The absolute configuration was determined, based on resonant scattering of light atoms in Cu Kα radiation
Phase Diagram and Magnetocaloric Effects in Aluminum Doped MnNiGe Alloys
The magnetocaloric and thermomagnetic properties of the MnNiGe1-xAlx system have been studied by temperature- dependent x- ray diffraction, differential scanning calorimetry (DSC), and magnetization measurements. The partial substitution of Al for Ge in MnNiGe1-xAlx results in a first order magnetostructural transition (MST) from a hexagonal ferromagnetic to an orthorhombic antiferromagnetic phase at 186K (for x 0.09). A large magnetic entropy change of Delta SM = - 17.6 J/kg K for DeltaH = 5T was observed in the vicinity of TM 186K for x 0.09. The value is comparable to those of giant magnetocaloric materials such as Gd5Si2Ge2, MnFeP0.45As0.55, and Ni50Mn37Sn13. The values of the latent heat (L 6.6 J/g) and corresponding total entropy changes (DeltaST 35 J/kg K) have been evaluated for the MST using DSC measurements. Large negative values of Delta SM of - 5.8 and - 4.8 J/kg K for DeltaH = 5T in the vicinity of TC were observed for x 0.09 and 0.085, respectively. A concentration- dependent phase diagram of transition temperatures (magnetic, structural, and magnetostructural) has been generated using magnetic, XRD, and DSC data. The role of magnetic and structural changes on transition temperatures is discussed
Open-label, single-dose, parallel-group study in healthy volunteers to determine the drug-drug interaction potential between KAE609(Cipargamin) and Piperaquine
KAE609 represents a new class of potent, fast-acting, schizonticidal antimalarials. This study investigated the safety and pharmacokinetics of KAE609 in combination with the long-acting antimalarial piperaquine (PPQ) in healthy volunteers. A two-way pharmacokinetic interaction was hypothesized for KAE609 and PPQ, as both drugs are CYP3A4 substrates and inhibitors. The potential for both agents to affect the QT interval was also assessed. This was an open-label, parallel-group, single-dose study with healthy volunteers. Subjects were randomized to four parallel dosing arms with five cohorts (2:2:2:2:1), receiving 75 mg KAE609 plus 320 mg PPQ, 25 mg KAE609 plus 1,280 mg PPQ, 25 mg KAE609 alone, 320 mg PPQ alone, or 1,280 mg PPQ alone. Triplicate electrocardiograms were performed over the first 24 h after dosing, with single electrocardiograms at other time points. Routine safety (up to 89 days) and pharmacokinetic (up to 61 days) assessments were performed. Of the 110 subjects recruited, 99 completed the study. Coadministration of PPQ had no overall effect on exposure to KAE609, although 1,280 mg PPQ decreased the KAE609 maximum concentration (Cmax) by 17%. The group that received 25 mg KAE609 plus 1,280 mg PPQ showed a 32% increase in the PPQ area under the concentration-time curve from 0 to infinity (AUCinf), while the group that received 75 mg KAE609 plus 320 mg PPQ showed a 14% reduction. Mean changes from baseline in the QT interval corrected by Fridericia's method (QTcF) and the QT interval corrected by Bazett's method (QTcB) with PPQ were consistent with its known effects. PPQ but not KAE609 exposure correlated with corrected QT interval (QTc) increases, and KAE609 did not affect the PPQ exposure-QTc relationship. The QTcF effect for PPQ (least-squares estimate of the difference in mean maximal changes from baseline of 7.47 ms [90% confidence interval, 3.55 to 11.4 ms]) was consistent with the criteria for a positive thorough QT study. No subject had QTcF or QTcB values of >500 ms. Both drugs given alone or in combination were well tolerated, with no deaths, serious adverse events (AEs), or severe AEs reported. Most AEs were mild; upper respiratory tract infections, headache, diarrhea, and oropharyngeal pain were most common. PPQ and KAE609 coadministration had no relevant effect on exposure to either agent, and KAE609 did not affect or potentiate the known effects of PPQ on cardiac conduction
Basic psychological need satisfaction and frustration in major depressive disorder
Basic psychological needs theory postulates that a social environment that satisfies individuals’ three basic psychological needs of autonomy, competence, and relatedness leads to optimal growth and well-being. On the other hand, the frustration of these needs is associated with ill-being and depressive symptoms foremost investigated in non-clinical samples; yet, there is a paucity of research on need frustration in clinical samples. Survey data were compared between adult individuals with major depressive disorder (MDD; n = 115; 48.69% female; 38.46 years, SD = 10.46) with those of a non-depressed comparison sample (n = 201; 53.23% female; 30.16 years, SD = 12.81). Need profiles were examined with a linear mixed model (LMM). Individuals with depression reported higher levels of frustration and lower levels of satisfaction in relation to the three basic psychological needs when compared to non-depressed adults. The difference between depressed and non-depressed groups was significantly larger for frustration than satisfaction regarding the needs for relatedness and competence. LMM correlation parameters confirmed the expected positive correlation between the three needs. This is the first study showing substantial differences in need-based experiences between depressed and non-depressed adults. The results confirm basic assumptions of the self-determination theory and have preliminary implications in tailoring therapy for depression
A 183 GHz metamorphic HEMT low-noise amplifier with 3.5 dB noise figure
This paper presents a 183 GHz low-noise amplifier (LNA), designed primarly for water vapor detection in atmosphere. The LNA requirements were defined by MetOp Second Generation (MetOp-SG) Microwave Sounder, Microwave Imager and Ice Cloud Imager instruments. MetOp-SG is the European contribution to operational meteorological observations from polar orbit. This LNA advances the current state-of-the-art for the InGaAs metamorphic high electron
mobility transistor (mHEMT) technology. The five-stage common-source MMIC amplifier utilizes transistors with a gate length of 50 nm. On-wafer measurements show a noise figure of 3.5 dB at the operative frequency, about 1 dB lower than previously reported mHEMT LNAs, and a gain of 24±2 dB over the bandwidth 160-200 GHz. The input and output matching are -11 dB and -10 dB, respectively. Moreover, the DC power dissipation at the optimal bias for noise is as low as 24 mW
Landsat archive holdings for Finland : opportunities for forest monitoring
There is growing interest in the use of Landsat data to enable forest monitoring over large areas. Free and open data access combined with high performance computing have enabled new approaches to Landsat data analysis that use the best observation for any given pixel to generate an annual, cloud-free, gap-free, surface reflectance image composite. Finland has a long history of incorporating Landsat data into its National Forest Inventory to produce forest information in the form of thematic maps and small area statistics on a variety of forest attributes. Herein we explore the spatial and temporal characteristics of the Landsat archive in the context of forest monitoring in Finland. The United States Geological Survey Landsat archive holds a total of 30 076 images (1972-2017) for 66 scenes (each 185 km by 185 km in size) representing the terrestrial area of Finland, of which 93.6% were acquired since 1984 with a spatial resolution of 30 m. Approximately 16.3% of the archived images have desired compositing characteristics (acquired within August 1 +/- 30 days,Peer reviewe
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