151 research outputs found
An examination of the Michigan 2010 motor vehicle traffic crash fatality increase
In 2010, national fatal crash counts went down by 3.5%, following on the heels of substantial drops in 2008 and 2009. However, in Michigan, fatal crashes were down substantially in 2009, but up by nearly 8% in 2010. This report contains an in-depth look at the patterns associated with Michigan’s fatal crash increase in 2010. In particular, we present a time series analysis of fatal-crash trends over the last 40 years. In addition, we provide breakdowns of crash subcategories, focusing on alcohol and drug use by drivers, commercial vehicles, young and elderly drivers, motorcycles, and construction-zone crashes. Finally, we compare the pattern in Michigan to the patterns of fatal crashes for three other states. The primary result of these analyses is that 2009 was unusually low in fatal crashes and 2010 represents a return to normal numbers. That said, fatal-crash-involved drivers testing positive for blood THC have more than doubled in 2010. In addition, construction zone crashes have increased, though the base numbers are too low to determine whether the increase is significant. Motorcycle fatalities showed large increases in 2010, especially in collisions with other motor vehicles. In the multi-state comparison, the nearest state, Wisconsin, showed the same 2009 decrease and 2010 increase in total crashes, while more distant states of Idaho and Missouri showed steady decreases. These results are consistent with regional trends reported by NHTSA. The four states showed similar results with steady decreases in overall crashes and steady increases in drug-related fatal crashes.Michigan Office of Highway Safety Planninghttp://deepblue.lib.umich.edu/bitstream/2027.42/89936/1/102816.pd
Occurrence of chicken infectious anemia virus in industrial and backyard tunisian broilers: Preliminary results
Chicken infectious anemia virus (CIAV) is an economically important and widely distributed immunosuppressive agent in chickens. This study performed an epidemiological investigation on CIAV circulation in 195 Tunisian broilers, belonging to 13 lots from five industrial farms and in one rural farm. Fifteen animals were detected positive by a VP1 nested PCR. The amplicons were molecularly characterised by complete genome sequencing. All positive samples obtained in this study were from the rural farm, whereas the industrial farms sampled were negative. Nucleotide and amino acid sequence analyses showed a high degree of similarity among the sequences obtained, suggesting the circulation of a single CIAV strain in the positive lot. Phylogenetic analysis based on the CIAV VP1 nucleotide sequence and/or the complete genome showed that the sequences obtained in this study clustered with CIAV strains previously detected in Tunisia, Italy and Egypt, belonging to genogroup II. Our results highlight the need for constant CIAV surveillance in backyard chicken production
Thermoelectric Limitations of Graphene Nanodevices at Ultrahigh Current Densities.
Graphene is atomically thin, possesses excellent thermal conductivity, and is able to withstand high current densities, making it attractive for many nanoscale applications such as field-effect transistors, interconnects, and thermal management layers. Enabling integration of graphene into such devices requires nanostructuring, which can have a drastic impact on the self-heating properties, in particular at high current densities. Here, we use a combination of scanning thermal microscopy, finite element thermal analysis, and operando scanning transmission electron microscopy techniques to observe prototype graphene devices in operation and gain a deeper understanding of the role of geometry and interfaces during high current density operation. We find that Peltier effects significantly influence the operational limit due to local electrical and thermal interfacial effects, causing asymmetric temperature distribution in the device. Thus, our results indicate that a proper understanding and design of graphene devices must include consideration of the surrounding materials, interfaces, and geometry. Leveraging these aspects provides opportunities for engineered extreme operation devices
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High-K dielectric sulfur-selenium alloys.
Upcoming advancements in flexible technology require mechanically compliant dielectric materials. Current dielectrics have either high dielectric constant, K (e.g., metal oxides) or good flexibility (e.g., polymers). Here, we achieve a golden mean of these properties and obtain a lightweight, viscoelastic, high-K dielectric material by combining two nonpolar, brittle constituents, namely, sulfur (S) and selenium (Se). This S-Se alloy retains polymer-like mechanical flexibility along with a dielectric strength (40 kV/mm) and a high dielectric constant (K = 74 at 1 MHz) similar to those of established metal oxides. Our theoretical model suggests that the principal reason is the strong dipole moment generated due to the unique structural orientation between S and Se atoms. The S-Se alloys can bridge the chasm between mechanically soft and high-K dielectric materials toward several flexible device applications
Circulating MicroRNA-15a Associates With Retinal Damage in Patients With Early Stage Type 2 Diabetes
: Circulating microRNAs are potential biomarkers of type 2 diabetes mellitus (T2DM) and related complications. Here, we investigated the association of microRNA-15a with early retinal damage in T2DM. A cohort of untreated subjects screened for intermediate/high risk of T2DM, according to a score assessment questionnaire, and then recognized to have a normal (NGT) or impaired (IGT) glucose tolerance or T2DM was studied. The thickness of the ganglion cell complex (GCC), an early marker of retinal degeneration anteceding overt retinopathy was assessed by Optical Coherence Tomography. Total and extracellular vesicles (EV)-associated microRNA-15a quantity was measured in plasma by real time PCR. MicroRNA-15a level was significantly higher in subjects with IGT and T2DM compared with NGT. MicroRNA-15a abundance was correlated to body mass index and classical diabetes biomarkers, including fasting glucose, HbA1c, insulinemia, and HOMA-IR. Moreover, GCC thickness was significantly reduced in IGT and T2DM subjects compared with NGT controls. Importantly, total microRNA-15a correlated with GCC in IGT subjects, while in T2DM subjects, EV-microRNA-15a negatively correlated with GCC, suggesting that microRNA-15a may monitor initial retinal damage. The assessment of plasma microRNA-15a may help refining risk assessment and secondary prevention in patients with preclinical T2DM
Spatial symmetry constraint of charge-ordered kagome superconductor CsVSb
Elucidating the symmetry of intertwined orders in exotic superconductors is
at the quantum frontier. Recent surface sensitive studies of the topological
kagome superconductor CsVSb discovered a cascade 4a superlattice
below the charge density wave (CDW) ordering temperature, which can be related
to the pair density modulations in the superconducting state. If the 4a
phase is a bulk and intrinsic property of the kagome lattice, this would form a
striking analogy to the stripe order and pair density wave discovered in the
cuprate high-temperature superconductors, and the cascade ordering found in
twisted bilayer graphene. High-resolution X-ray diffraction has recently been
established as an ultra-sensitive probe for bulk translational
symmetry-breaking orders, even for short-range orders at the diffusive limit.
Here, combining high-resolution X-ray diffraction, scanning tunneling
microscopy and scanning transmission electron microscopy, we demonstrate that
the 4a superstructure emerges uniquely on the surface and hence exclude the
4a phase as the origin of any bulk transport or spectroscopic anomaly.
Crucially, we show that our detected 222 CDW order breaks the
bulk rotational symmetry to C2, which can be the driver for the bulk nematic
orders and nematic surface superlattices including the 4a phase. Our
high-resolution data impose decisive spatial symmetry constraints on emergent
electronic orders in the kagome superconductor CsVSb
Genetic dynamics in untreated CLL patients with either stable or progressive disease: A longitudinal study
Clonal evolution of chronic lymphocytic leukemia (CLL) often follows chemotherapy and is associated with adverse outcome, but also occurs in untreated patients, in which case its predictive role is debated. We investigated whether the selection and expansion of CLL clone(s) precede an aggressive disease shift. We found that clonal evolution occurs in all CLL patients, irrespective of the clinical outcome, but is faster during disease progression. In particular, changes in the frequency of nucleotide variants (NVs) in specific CLL-related genes may represent an indicator of poor clinical outcome
Giant Modulation of Refractive Index from Correlated Disorder
Correlated disorder has been shown to enhance and modulate magnetic,
electrical, dipolar, electrochemical and mechanical properties of materials.
However, the possibility of obtaining novel optical and opto-electronic
properties from such correlated disorder remains an open question. Here, we
show unambiguous evidence of correlated disorder in the form of anisotropic,
sub-angstrom-scale atomic displacements modulating the refractive index tensor
and resulting in the giant optical anisotropy observed in BaTiS3, a
quasi-one-dimensional hexagonal chalcogenide. Single crystal X-ray diffraction
studies reveal the presence of antipolar displacements of Ti atoms within
adjacent TiS6 chains along the c-axis, and three-fold degenerate Ti
displacements in the a-b plane. 47/49Ti solid-state NMR provides additional
evidence for those Ti displacements in the form of a three-horned NMR lineshape
resulting from low symmetry local environment around Ti atoms. We used scanning
transmission electron microscopy to directly observe the globally disordered Ti
a-b plane displacements and find them to be ordered locally over a few unit
cells. First-principles calculations show that the Ti a-b plane displacements
selectively reduce the refractive index along the ab-plane, while having
minimal impact on the refractive index along the chain direction, thus
resulting in a giant enhancement in the optical anisotropy. By showing a strong
connection between correlated disorder and the optical response in BaTiS3, this
study opens a pathway for designing optical materials with high refractive
index and functionalities such as a large optical anisotropy and nonlinearity.Comment: 24 pages, 3 figure
High-throughput 18K SNP array to assess genetic variability of the main grapevine cultivars from Sicily
The viticulture of Sicily, for its vocation, is one of the most important and ancient forms in Italy. Autochthonous grapevine cultivars, many of which known throughout the world, have always been cultivated in the island from many centuries. With the aim to preserve this large grapevine diversity, previous studies have already started to assess the genetic variability among the Sicilian cultivars by using morphological and microsatellite markers. In this study, simple sequence repeat (SSR) were utilized to verify the true-to-typeness of a large clone collection (101) belonging to 21 biotypes of the most 10 cultivated Sicilian cultivars. Afterwards, 42 Organization Internationale de la Vigne et du Vin (OIV) descriptors and a high-throughput single nucleotide polymorphism (SNP) genotyping array (Vitis18kSNP) were applied to assess genetic variability among cultivars and biotypes of the same cultivar. Ampelographic traits and high-throughput SNP genotyping platforms provided an accuracy estimation of genetic diversity in the Sicilian germplasm, showing the relationships among cultivars by cluster and multivariate analyses. The large SNP panel defined sub-clusters unable to discern among biotypes, previously classified by ampelographic analysis, belonging to each cultivar. These results suggested that a very large number of SNP did not cover the genome regions harboring few morphological traits. Genetic structure of the collection revealed a clear optimum number of groups for K = 3, clustering in the same group a significant portion of family-related genotypes. Parentage analysis highlighted significant relationships among Sicilian grape cultivars and Sangiovese, as already reported, but also the first evidences of the relationships between Nero d’Avola and both Inzolia and Catarratto. Finally, a small panel of highly informative markers (12 SNPs) allowed us to isolate a private profile for each Sicilian cultivar, providing a new tool for cultivar identification
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