IL‐7 is produced by stromal cells in bone marrow and is a major regulator of B and T lymphopoiesis. It is also a direct inhibitor of osteoclastogenesis in vitro. In this study we show that ...IL‐7–deficient mice have increased OC and decreased trabecular bone volume compared with WT mice but mimic WT mice in the amount of trabecular but not cortical bone lost after ovariectomy.
Introduction: Interleukin (IL)‐7 is a potent regulator of lymphocyte development, which has significant effects on bone. Bone marrow cell cultures from IL‐7 deficient (IL‐7KO) mice produced significantly more TRACP+ osteoclasts (OCs) than did cells from wildtype (WT) mice. A previous study found that treatment of mice with a neutralizing antibody to IL‐7 blocked ovariectomy (OVX)‐induced bone loss. We examined if differences exist between the bones of WT and IL‐7KO mice and if OVX altered bone mass in IL‐7KO mice.
Materials and Methods: Studies were in 2‐month‐old sham‐operated (SHAM) and OVX female mice that were killed 4 weeks after surgery. IL‐7KO mice and WT controls were in a C57BL/6 background. Both vertebrae (L1) and femora were evaluated by DXA, μCT, and histomorphometry. IL‐7KO mice were confirmed as IL‐7 deficient by their almost total lack of mature B cells in their bone marrow.
Results: There was significantly less trabecular bone volume in the vertebrae of IL‐7KO mice than in WT mice. In addition, IL‐7KO mice had significantly decreased (p < 0.05) trabecular number (13%) and increased trabecular spacing (15%). OVX decreased vertebral trabecular bone volume (TBV) by 21% (p < 0.05) in WT mice and by 22% (p < 0.05) in IL‐7KO mice compared with SHAM. IL‐7KO SHAM mice also had significantly less (30%) TBV (TA/TTA) in their femurs, as measured histomorphometrically, than did WT SHAM mice. Femurs from IL‐7KO SHAM mice had significantly increased percent OC surface (23%) compared with WT SHAM. As in the vertebrae, OVX significantly decreased femoral TBV in both WT and IL‐7KO mice by similar amounts (47% and 48%, respectively, p < 0.05 for both) compared with SHAM. However, OVX decreased cortical bone mass in WT but not in IL‐7KO bones. We also examined bone marrow cells from WT and IL‐7KO mice. Bone marrow cells from IL‐7KO animals showed a significant increase in the number of TRACP+ osteoclast‐like cells (OCLs), which formed in cultures that were stimulated with macrophage‐colony stimulating factor (M‐CSF) and RANKL (both at 30 ng/ml). However, there was no significant difference in the number of OCLs that formed in B lymphocyte–depleted (B220−) bone marrow cell cultures from WT and IL‐7KO mice.
Conclusions: IL‐7 deficiency in mice caused increased OC number in bone and decreased bone mass. OVX‐induced bone loss in IL‐7–deficient mice was selective and occurred in trabecular but not cortical bone.
A highly efficient exciplex electrophosphorescent diode has been fabricated. The efficiency as high as 2.4% photon/carrier is achieved from the above double-layer structure using the organic ...materials as indicated in the figure. The emission originated from triplet exciplexes
3∣m-MTDATA:PtL
2Cl〉
∗ formed in the blend emitter m-MTDATA:BPT (1:1) 70
wt%: PtL
2Cl 5
wt%:PC 25
wt% (70
nm) separated from the cathode by a 50
nm-thick BPT layer.
The efficiency of organic exciplex light-emitting-devices (EXLEDs) can be greatly improved by introduction of a phosphorescent sensitizer with a high electronic affinity. In the electron–hole combination process at the electron donor/acceptor interface, solely singlet exciplexes are generated producing the exciplex fluorescence. A phosphor sensitizer allows the formation in the emitter bulk of triplet exciplexes, which yield highly efficient exciplex phosphorescence. As an example, we use a Pt-based phosphor (PtL
2Cl) doped into a star-burst amine hole transporting donor (m-MTDATA) and bathophenanthroline (BPT) electron-transporting acceptor system which in a bi-layer EXLED reveals an exciplex high electro-phosphorescence external quantum yield of 2.4% photon/carrier.
Regenerated fiber Bragg grating (RFBG) sensors for thermal aging at high temperatures from 600 °C to 1000 °C are produced and analyzed in this work. Seed FBGs are regenerated at 850 °C-900 °C and ...thermal characterized at the increasing steps of 50 °C-100 °C. Signal decay is measured from the reflected spectra until imminent erasure. The objective is to analyze the RFBG sensors lifetime above the regeneration temperature for long periods after annealing cycles with increasing thermal levels. Lifetime results from RFBG were reported to be a few hours above their regeneration temperature. Our results are significantly better. The sensors resisted for the time intervals of one to eight days up to 100 °C above the regeneration temperature. In addition, some sensors remained stable in terms of the spectral amplitude for more than four days in that thermal condition.
A study of the current–electric field characteristics of single layer structures Quartz/ITO/TPD/Al and Quartz/Al
1/TPD/Al
2, containing the vacuum evaporated films of a diamine derivative (TPD) used ...commonly as a hole-transporting material in organic light emitting diodes, was carried out. The currents are dominated by injection of holes independent on the bias of the electrical contacts. In addition to an obvious asymmetry in the currents for ITO
+ and ITO
− biased contacts, a distinct asymmetry for aluminum
Al
1
+
and
Al
1
-
biased contact is observed. The results have been interpreted in terms of the injection-limited current theory accounted for the electrode and bi-molecular recombination.
To construct macro- and microarray tools suitable for expression profiling in root endosymbioses of the model legume
Medicago truncatula, we PCR-amplified a total of 6048 cDNA probes representing ...genes expressed in uninfected roots, mycorrhizal roots and young root nodules Nucleic Acids Res. 30 (2002) 5579. Including additional probes for either tissue-specific or constitutively expressed control genes, 5651 successfully amplified gene-specific probes were used to grid macro- and to spot microarrays designated Mt6k-RIT (
M.
truncatula 6k root interaction transcriptome). Subsequent to a technical validation of microarray printing, we performed two pilot expression profiling experiments using Cy-labeled targets from
Sinorhizobium meliloti-induced root nodules and
Glomus intraradices-colonized arbuscular mycorrhizal roots. These targets detected marker genes for nodule and arbuscular mycorrhiza development, amongst them different nodule-specific leghemoglobin and nodulin genes as well as a mycorrhiza-specific phosphate transporter gene. In addition, we identified several dozens of genes that have so far not been reported to be differentially expressed in nodules or arbuscular mycorrhiza thus demonstrating that Mt6k-RIT arrays serve as useful tools for an identification of genes relevant for legume root endosymbioses. A comprehensive profiling of such candidate genes will be very helpful to the development of breeding strategies and for the improvement of cultivation management targeted at increasing legume use in sustainable agricultural systems.
Connecticut's novel approach to collecting and analyzing traffic stop data for evidence of disparate treatment is widely considered to be a model of best practice. Here, we provide an overview of ...Connecticut's framework, detail solutions to the canonical empirical challenges of analyzing traffic stop, and describe a data‐driven approach to early intervention. Unlike most jurisdictions that simply produce an annual traffic stop report, Connecticut has developed an ongoing system for identifying and mitigating disparity. Connecticut's framework for identifying significant disparities on an annual basis relies on the so‐called “preponderance of evidence” approach. Drawing from the cutting‐edge of the empirical social science literature, this approach applies several, as opposed to a single, rigorous empirical test of disparity. For departments identified as having a disparity, Connecticut has developed a process for intervening on an annual basis. In that process, policing administrators engage with researchers to conduct an empirical exploration into possible contributing factors and enforcement policies. In Connecticut, this approach has transformed what had once been a war of anecdotes into a constructive data‐driven conversation about policy. Variants of the Connecticut Model have recently been adopted by the State of Rhode Island, Oregon, and California. Connecticut's approach provides a useful model and policy framework for states and localities conducting disparity studies of police traffic stops.
For large masses, the two heavy neutral Higgs bosons are nearly degenerate in many 2-Higgs doublet models, and particularly in supersymmetric models. In such a scenario the mixing between the states ...can be very large if the theory is CP-noninvariant. We analyze the formalism describing this configuration, and we point to some interesting experimental consequences.
We have investigated strong photoluminescence quenching (over 50%) in an important class of line-like emitters (organolanthanides) by measuring the time-resolved emission from their films to which ...increasing fields up to 2.7
MV/cm have been applied. By manipulating the electrode materials and their electrical bias, we have been able to show that two mechanisms are equally effective in reducing the emission quantum yield, namely (i) the electric field-enhanced dissociation of the ligand precursor excited states of the emissive lanthanide ion states, and (ii) the interaction of the precursor states with the field-increasing charge injected from electrodes into the films.
Strong total (
δ
tot) and amplitude (
δ
amplitude) luminescence quenching (over 50%) in line-like emitters (organolanthanides) has been observed from the time-resolved emission at increasing electric fields. By manipulating the electrode materials and their electrical bias, it has been possible to show that two mechanisms are equally effective in reducing the emission quantum yield, (i) the electric field-enhanced dissociation of the ligand precursor excited states of the emissive lanthanide ion states, and (ii) the interaction of the precursor states with the charge injected from electrodes into the emitters.
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