405 research outputs found
Determination of the magnetization profile of Co/Mg periodic multilayers by magneto-optic Kerr effect and X-ray magnetic resonant reflectivity
The resonant magnetic reflectivity of Co/Mg multilayers around the Co L2,3
absorption edge is simulated then measured on a specifically designed sample.
The dichroic signal is obtained when making the difference between the two
reflectivities measured with the magnetic field applied in two opposite
directions parallel to the sample surface. The simulations show that the
existence of magnetic dead layers at the interfaces between the Co and Mg
layers leads to an important increase of the dichroic signal measured in the
vicinity of the third Bragg peak that otherwise should be negligible. The
measurements are in agreement with the model introducing 0.25 nm thick dead
layers. This is attributed to the Co atoms in contact with the Mg layers and
thus we conclude that the Co-Mg interfaces are abrupt from the magnetic point
of view.Comment: 8 page
Three-Dimensional Morphological Changes of the True Cleft under Passive Presurgical Orthopaedics in Unilateral Cleft Lip and Palate: A Retrospective Cohort Study
The aim of this cohort study was to quantify the morphological changes in the palatal cleft and true cleft areas with passive plate therapy using a new analysis method based on three-dimensional standardized reproducible landmarks. Forty-five casts of 15 consecutive patients with complete unilateral cleft lip and palate were laser scanned and investigated retrospectively. The landmarks and the coordinate system were defined, and the interrater and intrarater measurement errors were within 1.0 mm. The morphological changes of the cleft palate area after a period of 8 months of passive plate therapy without prior lip surgery are presented graphically. The median decrease in cleft width was 38.0% for the palatal cleft, whereas it was 44.5% for the true cleft. The width of the true and palatal cleft decreased significantly over a period of 8 months. The true cleft area decreased by 34.7% from a median of 185.4 mm2 (interquartile range, IQR = 151.5âEuro"220.1) to 121.1 mm2 (IQR = 100.2âEuro"144.6). The palatal cleft area decreased by 31.5% from a median of 334 mm2 (IQR = 294.9âEuro"349.8) to 228.8 mm2. The most important clinical considerations are the reproducibility and reliability of the anatomical points, as well as the associated morphological changes. We propose using the vomer edge to establish a validated measuring method for the width, area, and height of the true cleft
Identification of hidden orbital contributions in the La_{0.65} Sr_{0.35} MnO_{3} valence band
Hybridization of electronic states and orbital symmetry in transition metal oxides are generally considered key ingredients in the description of both their electronic and magnetic properties. In the prototypical case of La_{0.65} Sr_{0.35} MnO_{3} (LSMO), a landmark system for spintronics applications, a description based solely on Mn 3d and O 2p electronic states is reductive. We thus analyzed elemental and orbital distributions in the LSMO valence band through a comparison between density functional theory calculations and experimental photoelectron spectra in a photon energy range from soft to hard x rays. We reveal a number of hidden contributions, arising specifically from La 5p, Mn 4s, O 2s orbitals, considered negligible in previous analyses; our results demonstrate that all these contributions are significant for a correct description of the valence band of LSMO and of transition metal oxides in general
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Preliminary Biomarkers for Identification of Human Ascending Thoracic Aortic Aneurysm
Background: Human ascending thoracic aortic aneurysms (ATAAs) are life threatening and constitute a leading cause of mortality in the United States. Previously, we demonstrated that collagens α2(V) and α1(XI) mRNA and protein expression levels are significantly increased in ATAAs. Methods and Results: In this report, the authors extended these preliminary studies using high‐throughput proteomic analysis to identify additional biomarkers for use in whole blood real‐time RT‐PCR analysis to allow for the identification of ATAAs before dissection or rupture. Human ATAA samples were obtained from male and female patients aged 65±14 years. Both bicuspid and tricuspid aortic valve patients were included and compared with nonaneurysmal aortas (mean diameter 2.3 cm). Five biomarkers were identified as being suitable for detection and identification of ATAAs using qRT‐PCR analysis of whole blood. Analysis of 41 samples (19 small, 13 medium‐sized, and 9 large ATAAs) demonstrated the overexpression of 3 of these transcript biomarkers correctly identified 79.4% of patients with ATAA of ≥4.0 cm (P<0.001, sensitivity 0.79, CI=0.62 to 0.91; specificity 1.00, 95% CI=0.42 to 1.00). Conclusion: A preliminary transcript biomarker panel for the identification of ATAAs using whole blood qRT‐PCR analysis in men and women is presented
Structural characteristics correlate with immune responses induced by HIV envelope glycoprotein vaccines
AbstractHIV envelope glycoprotein (Env) is the target for inducing neutralizing antibodies. Env is present on the virus surface as a trimer, and, upon binding to CD4, a cascade of events leads to structural rearrangement exposing the co-receptor binding site and entry into the CD4+ host target cells. We have designed monomeric and trimeric Env constructs with and without deletion of the variable loop 2 (ΔV2) from SF162, a subtype B primary isolate, and performed biophysical, biochemical and immunological studies to establish a potential structure–functional relationship. We expressed these Envs in CHO cells, purified the proteins to homogeneity and performed biophysical studies to define the binding properties to CD4, structural characteristics and exposure of epitopes recognized by b12 and CD4i mAb (17B) on both full-length and mutant HIV Env proteins. Parameters evaluated include oligomerization state, number and affinity of CD4 binding sites, enthalpy and entropy of the Env–CD4 interaction and affinity for b12 and 17b mAbs. We observed one CD4 binding site per monomer and three active CD4 binding sites per trimer. A 40-fold difference in affinity of the gp120 monomer vs. the o-gp140 trimer towards CD4 was observed (Kd = 58 nM and 1.5 nM, respectively), whereas only a 2-fold difference was observed for the V2 deleted Envs (Kd of gp120ΔV2 = 19 nM, Kd of o-gp140DV2 = 9.3 nM). Monomers had 3-fold higher affinity to the mAb 17b and at least 3-fold weaker affinity to b12 compared to trimers, with gp120DV2 having the weakest affinity for b12 (Kd = 446 nM). Affinity of CD4 binding correlated with proportion of the antibodies induced against the conformational epitopes by the corresponding Envs, and changes in mAb binding correlated with the induction of antibodies directed against linear epitopes. Furthermore, biophysical analysis reveals that the V2 deletion has broad structural implications in the monomer not shared by the trimer, and these changes are reflected in the quality of the immune responses induced in rabbits. These data suggest that biophysical characteristics of HIV Env, such as affinity for CD4, and exposure of important neutralizing epitopes, such as those recognized by b12 mAb, may be important predictors of its in vivo efficacy and may serve as important surrogate markers for screening Env structures as potential vaccine candidates
Randomized clinical trial of therapeutic music video intervention for resilience outcomes in adolescents/young adults undergoing hematopoietic stem cell transplant: a report from the Children's Oncology Group
BACKGROUND:
To reduce the risk of adjustment problems associated with hematopoietic stem cell transplant (HSCT) for adolescents/young adults (AYAs), we examined efficacy of a therapeutic music video (TMV) intervention delivered during the acute phase of HSCT to: 1) increase protective factors of spiritual perspective, social integration, family environment, courageous coping, and hope-derived meaning; 2) decrease risk factors of illness-related distress and defensive coping; and 3) increase outcomes of self-transcendence and resilience.
METHODS:
This was a multisite randomized, controlled trial (COG-ANUR0631) conducted at 8 Children's Oncology Group sites involving 113 AYAs aged 11-24 years undergoing myeloablative HSCT. Participants, randomized to the TMV or low-dose control (audiobooks) group, completed 6 sessions over 3 weeks with a board-certified music therapist. Variables were based on Haase's Resilience in Illness Model (RIM). Participants completed measures related to latent variables of illness-related distress, social integration, spiritual perspective, family environment, coping, hope-derived meaning, and resilience at baseline (T1), postintervention (T2), and 100 days posttransplant (T3).
RESULTS:
At T2, the TMV group reported significantly better courageous coping (Effect Size [ES], 0.505; P = .030). At T3, the TMV group reported significantly better social integration (ES, 0.543; P = .028) and family environment (ES, 0.663; P = .008), as well as moderate nonsignificant effect sizes for spiritual perspective (ES, 0.450; P = .071) and self-transcendence (ES, 0.424; P = .088).
CONCLUSIONS:
The TMV intervention improves positive health outcomes of courageous coping, social integration, and family environment during a high-risk cancer treatment. We recommend the TMV be examined in a broader population of AYAs with high-risk cancers
Clinical Best Practice Advice for Hepatology and Liver Transplant Providers During the COVID‐19 Pandemic: AASLD Expert Panel Consensus Statement
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/156235/2/hep31281.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156235/1/hep31281_am.pd
Tomato: a crop species amenable to improvement by cellular and molecular methods
Tomato is a crop plant with a relatively small DNA content per haploid genome and a well developed genetics. Plant regeneration from explants and protoplasts is feasable which led to the development of efficient transformation procedures.
In view of the current data, the isolation of useful mutants at the cellular level probably will be of limited value in the genetic improvement of tomato. Protoplast fusion may lead to novel combinations of organelle and nuclear DNA (cybrids), whereas this technique also provides a means of introducing genetic information from alien species into tomato. Important developments have come from molecular approaches. Following the construction of an RFLP map, these RFLP markers can be used in tomato to tag quantitative traits bred in from related species. Both RFLP's and transposons are in the process of being used to clone desired genes for which no gene products are known. Cloned genes can be introduced and potentially improve specific properties of tomato especially those controlled by single genes. Recent results suggest that, in principle, phenotypic mutants can be created for cloned and characterized genes and will prove their value in further improving the cultivated tomato.
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