Oscillator Strength of Metallic Carbon Nanotubes

Based on the tight binding method with hopping integral between the nearest-neighbor atoms, an oscillator strength \int_0^{\infty} \d \omega {\rm Re} \sigma (\omega) is discussed for armchair and metallic zigzag carbon nanotubes. The formulae of the oscillator strength are derived for both types of nanotubes and are compared with the result obtained by a linear chain model. In addition, the doping dependence is investigated in the absence of Coulomb interaction. It is shown that the oscillator strength of each carbon nanotube shows qualitatively the same doping dependence, but the fine structure is different due to it's own peculiar band structure. Some relations independent of the radius of the tube are derived, and a useful formula for determining the amount of doping is proposed.Comment: 4 pages, 4 figures, submitted to J. Phys. Soc. Jpn. at June 30, 200

Predictors Of Breast Density In Hispanic And Latino Women Living In The Northeast Region Of The United States

Introduction: Breast density, the fibroglandular, non-fatty tissue in the breast, has been shown to be a significant risk factor for breast cancer. Little is currently known about the predictors of breast density among the understudied but increasing population of Hispanic and Latino women in the United States. Objectives: The objective of this study is to identify predictors of breast density among Hispanic and Latino women in Connecticut and to determine if these differ from those described in other populations. Because the hormonal milieu is somewhat different in Hispanic/Latinas compared with White women, we are interested in how these variables impact breast density. We are primarily interested in the role of reproductive and physiological factors. Methods: We analyzed for breast density predictors in an established cohort of 1,600 Hispanic and Latino women recruited from primary care clinics in Connecticut. Baseline interview questions provided prospective data on biological, medical care, and sociodemographic factors. Subjects provided informed consent for the retrieval of mammography reports from screening facilities during the follow-up period. These reports provided breast density information based on radiologist assigned BI-RADS classification. Associations between predictors and breast density were examined with descriptive statistics and chi square statistical tests for which p-values were reported. We additionally calculated odds ratios and 95% confidence intervals using logistic regression modeling. Results: Breast density data were collected for 1,040 women (65.4%). 280 women (27%) were identified as having dense breasts while 760 women (73%) were classified as having nondense breasts based on screening mammogram reports. In the multivariate model, breast density predictors were generally consistent with those reported in previous studies. Additionally, we found women with diabetes to be at significantly reduced odds of breast density. There was also evidence that the relationship between age at menarche and density was modified by BMI. Conclusion: Our findings suggest that Hispanic and Latino women differ in breast density distribution relative to the general population. Additionally, we observed the protective effect of diabetes and potential interaction between age at menarche and BMI. This investigation enhances our understanding of breast density in Hispanic and Latino women and provides the basis for further research and inquiry within this population

Litigating Women: The Path to Intermediate Scrutiny in American Law

In the 1970s, the Supreme Court pronounced a new test for laws that treated the two sexes differently. This test, known as “intermediate scrutiny,” was stricter than the Court’s usual standard (the “rational basis” test), but not as stringent as the test used for cases involving racial distinction (the “strict scrutiny” test). It only applies to sex-based discrimination litigation. This work tracks and analyzes the jurisprudence in the Supreme Court that led to the implementation of intermediate scrutiny through examining different cases. These are Muller v. Oregon (1908); Goesaert v. Cleary (1948); Reed v. Reed (1971); Frontiero v. Richardson (1973); Weinberger v. Wiesenfeld (1975); and Craig v. Boren (1976). Muller and Goesaert demonstrate how the Court employed the rational basis test in sex-based discrimination cases during the first half of the Twentieth century. Reed, Frontiero, and Weinberger detail litigator and activist Ruth Bader Ginsburg’s efforts to persuade the court to establish a test specifically for evaluating these cases. Craig explains the monumental case that finally convinced the Court to pronounce intermediate scrutiny. Together, these six cases provide a cohesive narrative of the jurisprudence and socio-cultural history that clearly articulated the path to intermediate scrutiny

Effects of defatted dried roselle (Hibiscus sabdariffa L.) seed powder on lipid profiles of hypercholesterolemia rats.

BACKGROUND: In vivo investigations were made of the effect of defatted dried roselle seed powder (DRS) on the lipid profiles of rats with induced hypercholesterolemia. The two-batch sample consisted of 23 and 20 Sprague-Dawley male rats randomly divided into four groups and fed with four different diets. The first batch of rats was fed with normal, hypercholesterol, hypercholesterol + 10 g kg-1 (w/w) DRS and hypercholesterol + 20 g kg-1 (w/w) DRS diets. The second batch of rats was fed with normal, hypercholesterol, hypercholesterol + 50 g kg-1 (w/w) DRS and hypercholesterol + 150 g kg-1 (w/w) DRS diets. Treatments were given for a total of 5 weeks. RESULTS: Results indicated that the addition of 10 g kg-1 and 20 g kg-1 of DRS did not significantly lower the plasma total cholesterol (TC) levels. In contrast, 50 g kg-1 and 150 g kg-1 DRS significantly lowered (P < 0.05) the TC and low density lipoprotein cholesterol (LDL-C) levels. CONCLUSION: The addition of 50 g kg-1 and 150 g kg-1 DRS showed potential hypocholesterolemic effects. Furthermore, these findings indicated that protein, lipid and dietary fibre were high in the seed powder

\u3ci\u3eIn-Situ\u3c/i\u3e Raman Scattering Studies of Alkali-Doped Single Wall Carbon Nanotubes

Electrochemical doping and in-situ Raman scattering were used to study charge transfer in K- and Li-doped single wall carbon nanotubes (SWNT) as a function of alkali concentration. An 8 cm-1 downshift was observed for the tangential phonon mode of SWNT doped to stoichiometries of KC24 and Li1.25C6. The shift in both systems is reversible upon de-doping despite an irreversible loss of crystallinity. These results indicate that the tangential mode shifts result from electron transfer from alkali dopants to the SWNT, and that these modes are only weakly affected by long-range order within the ropes

Mentholation affects the cigarette microbiota by selecting for bacteria resistant to harsh environmental conditions and selecting against potential bacterial pathogens

There is a paucity of data regarding the microbial constituents of tobacco products and their impacts on public health. Moreover, there has been no comparative characterization performed on the bacterial microbiota associated with the addition of menthol, an additive that has been used by tobacco manufacturers for nearly a century. To address this knowledge gap, we conducted bacterial community profiling on tobacco from user- and custom-mentholated/non-mentholated cigarette pairs, as well as a commercially-mentholated product. Total genomic DNA was extracted using a multi-step enzymatic and mechanical lysis protocol followed by PCR amplification of the V3-V4 hypervariable regions of the 16S rRNA gene from five cigarette products (18 cigarettes per product for a total of 90 samples): Camel Crush, user-mentholated Camel Crush, Camel Kings, custom-mentholated Camel Kings, and Newport Menthols. Sequencing was performed on the Illumina MiSeq platform and sequences were processed using the Quantitative Insights Into Microbial Ecology (QIIME) software package. In all products, Pseudomonas was the most abundant genera and included Pseudomonas oryzihabitans and Pseudomonas putida, regardless of mentholation status. However, further comparative analysis of the five products revealed significant differences in the bacterial compositions across products. Bacterial community richness was higher among non-mentholated products compared to those that were mentholated, particularly those that were custom-mentholated. In addition, mentholation appeared to be correlated with a reduction in potential human bacterial pathogens and an increase in bacterial species resistant to harsh environmental conditions. Taken together, these data provide preliminary evidence that the mentholation of commercially available cigarettes can impact the bacterial community of these products.https://doi.org/10.1186/s40168-017-0235-