Exceptional Outgroup Stereotypes and White Racial Inequality Attitudes toward Asian Americans

Stereotypes of outgroups help create social identificational boundaries for ingroups. When the ingroup is dominant, members employ individualist sentiments to justify their status. In this study, we build on advances in social psychological research that account for multiple outgroup stereotypes. We argue the Asian American model minority stereotype is analogous to the “cold but competent” position of perceptions toward Asians in Fiske’s stereotype content model. Asian Americans are perceived to be exceptional to other minority groups, and we hypothesize that perceived competence is associated with individualist sentiments directed at Blacks and Latinos. Using data from the National Longitudinal Study of Freshmen, we find support for our hypotheses but find that perceived coldness has no relationship to individualist sentiments. We discuss the implications and directions for further research

Identifying Defects in Li-Ion Cells Using Ultrasound Acoustic Measurements

Identification of the state-of-health (SoH) of Li-ion cells is a vital tool to protect operating battery packs against accelerated degradation and failure. This is becoming increasingly important as the energy and power densities demanded by batteries and the economic costs of packs increase. Here, ultrasonic time-of-flight analysis is performed to demonstrate the technique as a tool for the identification of a range of defects and SoH in Li-ion cells. Analysis of large, purpose-built defects across multiple length scales is performed in pouch cells. The technique is then demonstrated to detect a microscale defect in a commercial cell, which is validated by examining the acoustic transmission signal through the cell. The location and scale of the defects are confirmed using X-ray computed tomography, which also provides information pertaining to the layered structure of the cells. The demonstration of this technique as a methodology for obtaining direct, non-destructive, depth-resolved measurements of the condition of electrode layers highlights the potential application of acoustic methods in real-time diagnostics for SoH monitoring and manufacturing processes

Magnetic vortex oscillator driven by dc spin-polarized current

Transfer of angular momentum from a spin-polarized current to a ferromagnet provides an efficient means to control the dynamics of nanomagnets. A peculiar consequence of this spin-torque, the ability to induce persistent oscillations of a nanomagnet by applying a dc current, has previously been reported only for spatially uniform nanomagnets. Here we demonstrate that a quintessentially nonuniform magnetic structure, a magnetic vortex, isolated within a nanoscale spin valve structure, can be excited into persistent microwave-frequency oscillations by a spin-polarized dc current. Comparison to micromagnetic simulations leads to identification of the oscillations with a precession of the vortex core. The oscillations, which can be obtained in essentially zero magnetic field, exhibit linewidths that can be narrower than 300 kHz, making these highly compact spin-torque vortex oscillator devices potential candidates for microwave signal-processing applications, and a powerful new tool for fundamental studies of vortex dynamics in magnetic nanostructures.Comment: 14 pages, 4 figure

Characterization and quantification of ammonia-oxidizing archaea (AOA) and bacteria (AOB) in a nitrogen-removing reactor using T-RFLP and qPCR

Using ammonia monooxygenase α-subunit (amoA) gene and 16S rRNA gene, the community structure and abundance of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) in a nitrogen-removing reactor, which was operated for five phases, were characterized and quantified by cloning, terminal restriction fragment length polymorphism (T-RFLP), and quantitative polymerase chain reaction (qPCR). The results suggested that the dominant AOB in the reactor fell to the genus Nitrosomonas, while the dominant AOA belonged to Crenarchaeotal Group I.1a in phylum Crenarchaeota. Real-time PCR results demonstrated that the levels of AOB amoA varied from 2.9 × 103 to 2.3 × 105 copies per nanogram DNA, greatly (about 60 times) higher than those of AOA, which ranged from 1.7 × 102 to 3.8 × 103 copies per nanogram DNA. This indicated the possible leading role of AOB in the nitrification process in this study. T-RFLP results showed that the AOB community structure significantly shifted in different phases while AOA only showed one major peak for all the phases. The analyses also suggested that the AOB community was more sensitive than that of AOA to operational conditions, such as ammonia loading and dissolved oxygen

Nanosilver Colloids-Filled Photonic Crystal Arrays for Photoluminescence Enhancement

For the improved surface plasmon-coupled photoluminescence emission, a more accessible fabrication method of a controlled nanosilver pattern array was developed by effectively filling the predefined hole array with nanosilver colloid in a UV-curable resin via direct nanoimprinting. When applied to a glass substrate for light emittance with an oxide spacer layer on top of the nanosilver pattern, hybrid emission enhancements were produced from both the localized surface plasmon resonance-coupled emission enhancement and the guided light extraction from the photonic crystal array. When CdSe/ZnS nanocrystal quantum dots were deposited as an active emitter, a total photoluminescence intensity improvement of 84% was observed. This was attributed to contributions from both the silver nanoparticle filling and the nanoimprinted photonic crystal array

Predictors of Radiotherapy Induced Bone Injury (RIBI) after stereotactic lung radiotherapy

<p>Abstract</p> <p>Background</p> <p>The purpose of this study was to identify clinical and dosimetric factors associated with radiotherapy induced bone injury (RIBI) following stereotactic lung radiotherapy.</p> <p>Methods</p> <p>Inoperable patients with early stage non-small cell lung cancer, treated with SBRT, who received 54 or 60 Gy in 3 fractions, and had a minimum of 6 months follow up were reviewed. Archived treatment plans were retrieved, ribs delineated individually and treatment plans re-computed using heterogeneity correction. Clinical and dosimetric factors were evaluated for their association with rib fracture using logistic regression analysis; a dose-event curve and nomogram were created.</p> <p>Results</p> <p>46 consecutive patients treated between Oct 2004 and Dec 2008 with median follow-up 25 months (m) (range 6 – 51 m) were eligible. 41 fractured ribs were detected in 17 patients; median time to fracture was 21 m (range 7 – 40 m). The mean maximum point dose in non-fractured ribs (n = 1054) was 10.5 Gy ± 10.2 Gy, this was higher in fractured ribs (n = 41) 48.5 Gy ± 24.3 Gy (p < 0.0001). On univariate analysis, age, dose to 0.5 cc of the ribs (D_0.5), and the volume of the rib receiving at least 25 Gy (V₂₅), were significantly associated with RIBI. As D_0.5 and V₂₅ were cross-correlated (Spearman correlation coefficient: 0.57, p < 0.001), we selected D_0.5 as a representative dose parameter. On multivariate analysis, age (odds ratio: 1.121, 95% CI: 1.04 – 1.21, p = 0.003), female gender (odds ratio: 4.43, 95% CI: 1.68 – 11.68, p = 0.003), and rib D_0.5 (odds ratio: 1.0009, 95% CI: 1.0007 – 1.001, p < 0.0001) were significantly associated with rib fracture.</p> <p>Using D_0.5, a dose-event curve was constructed estimating risk of fracture from dose at the median follow up of 25 months after treatment. In our cohort, a 50% risk of rib fracture was associated with a D_0.5 of 60 Gy.</p> <p>Conclusions</p> <p>Dosimetric and clinical factors contribute to risk of RIBI and both should be included when modeling risk of toxicity. A nomogram is presented using D_0.5, age, and female gender to estimate risk of RIBI following SBRT. This requires validation.</p

The Photodynamic Effect of Different Size ZnO Nanoparticles on Cancer Cell Proliferation In Vitro

Nanomaterials have widely been used in the field of biological and biomedicine, such as tissue imaging, diagnosis and cancer therapy. In this study, we explored the cytotoxicity and photodynamic effect of different-sized ZnO nanoparticles to target cells. Our observations demonstrated that ZnO nanoparticles exerted dose-dependent and time-dependent cytotoxicity for cancer cells like hepatocellular carcinoma SMMC-7721 cells in vitro. Meanwhile, it was observed that UV irradiation could enhance the suppression ability of ZnO nanoparticles on cancer cells proliferation, and these effects were in the size-dependent manner. Furthermore, when ZnO nanoparticles combined with daunorubicin, the related cytotoxicity of anticancer agents on cancer cells was evidently enhanced, suggesting that ZnO nanoparticles could play an important role in drug delivery. This may offer the possibility of the great potential and promising applications of the ZnO nanoparticles in clinical and biomedical areas like photodynamic cancer therapy and others

Measuring body composition in overweight individuals by dual energy x-ray absorptiometry

BACKGROUND: Dual energy x-ray absorptiometry (DXA) is widely used for body composition measurements in normal-weight and overweight/obese individuals. The limitations of bone densitometers have been frequently addressed. However, the possible errors in assessing body composition in overweight individuals due to incorrect positioning or limitations of DXA to accurately assess both bone mineral density and body composition in obese individuals have not received much attention and are the focus of this report. DISCUSSION: We discuss proper ways of measuring overweight individuals and point to some studies where that might not have been the case. It appears that currently, the most prudent approach to assess body composition of large individuals who cannot fit under the scanning area would be to estimate regional fat, namely the regions of thigh and/or abdomen. Additionally, using two-half body scans, although time consuming, may provide a relatively accurate measurement of total body fat, however, more studies using this technique are needed to validate it. SUMMARY: Researchers using bone densitometers for body composition measurements need to have an understanding of its limitations in overweight individuals and address them appropriately when interpreting their results. Studies on accuracy and precision in measurements of both bone and soft tissue composition in overweight individuals using available densitometers are needed

Calcium-fortified beverage supplementation on body composition in postmenopausal women

BACKGROUND: We investigated the effects of a calcium-fortified beverage supplemented over 12 months on body composition in postmenopausal women (n = 37, age = 48–75 y). METHODS: Body composition (total-body percent fat, %Fat(TB); abdominal percent fat, %Fat(AB)) was measured with dual energy x-ray absorptiometry. After baseline assessments, subjects were randomly assigned to a free-living control group (CTL) or the supplement group (1,125 mg Ca(++)/d, CAL). Dietary intake was assessed with 3-day diet records taken at baseline and 12 months (POST). Physical activity was measured using the Yale Physical Activity Survey. RESULTS: At 12 months, the dietary calcium to protein ratio in the CAL group (32.3 ± 15.6 mg/g) was greater than the CTL group (15.2 ± 7.5 mg/g). There were no differences from baseline to POST between groups for changes in body weight (CAL = 0.1 ± 3.0 kg; CTL = 0.0 ± 2.9 kg), %Fat(TB )(CAL = 0.0 ± 2.4%; CTL = 0.5 ± 5.4%), %Fat(AB )(CAL = -0.4 ± 8.7%; CTL = 0.6 ± 8.7%), or fat mass (CAL = 1.3 ± 2.6 kg; CTL = 1.3 ± 2.7 kg). CONCLUSION: These results indicate that increasing the calcium to protein ratio over two-fold by consuming a calcium-fortified beverage for 12 months did not decrease body weight, body fat, or abdominal fat composition in postmenopausal women

Properties of Graphene: A Theoretical Perspective

In this review, we provide an in-depth description of the physics of monolayer and bilayer graphene from a theorist's perspective. We discuss the physical properties of graphene in an external magnetic field, reflecting the chiral nature of the quasiparticles near the Dirac point with a Landau level at zero energy. We address the unique integer quantum Hall effects, the role of electron correlations, and the recent observation of the fractional quantum Hall effect in the monolayer graphene. The quantum Hall effect in bilayer graphene is fundamentally different from that of a monolayer, reflecting the unique band structure of this system. The theory of transport in the absence of an external magnetic field is discussed in detail, along with the role of disorder studied in various theoretical models. We highlight the differences and similarities between monolayer and bilayer graphene, and focus on thermodynamic properties such as the compressibility, the plasmon spectra, the weak localization correction, quantum Hall effect, and optical properties. Confinement of electrons in graphene is nontrivial due to Klein tunneling. We review various theoretical and experimental studies of quantum confined structures made from graphene. The band structure of graphene nanoribbons and the role of the sublattice symmetry, edge geometry and the size of the nanoribbon on the electronic and magnetic properties are very active areas of research, and a detailed review of these topics is presented. Also, the effects of substrate interactions, adsorbed atoms, lattice defects and doping on the band structure of finite-sized graphene systems are discussed. We also include a brief description of graphane -- gapped material obtained from graphene by attaching hydrogen atoms to each carbon atom in the lattice.Comment: 189 pages. submitted in Advances in Physic