356 research outputs found
Rolling friction of a viscous sphere on a hard plane
A first-principle continuum-mechanics expression for the rolling friction
coefficient is obtained for the rolling motion of a viscoelastic sphere on a
hard plane. It relates the friction coefficient to the viscous and elastic
constants of the sphere material. The relation obtained refers to the case when
the deformation of the sphere is small, the velocity of the sphere is
much less than the speed of sound in the material and when the characteristic
time is much larger than the dissipative relaxation times of the
viscoelastic material. To our knowledge this is the first ``first-principle''
expression of the rolling friction coefficient which does not contain empirical
parameters.Comment: 6 pages, 2 figure
Affordability issues in programming continuing care retirement communitites
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture and Dept. of Urban Studies and Planning, 1987.Bibliography: leaves 165-168.by Neil A.R. Prashad.M.S
Incidence of Buxtonella sulcata in Jaffrabadi buffaloes of south-western Gujarat, India
Present study was conducted to investigate the incidence of Buxtonella sulcata infection in Jaffrabadi buffaloes presented at Teaching Veterinary Clinical Complex (TVCC), Veterinary College, Junagadh during January 2013 to December 2014. A total of 206 rectal faecal samples of buffaloes was collected and processed in laboratory. The χ2 test was used to statistically analyse the significant differences (P≤0.05) among variables observed. The overall incidence of ciliated protozoa infection was 35.0%. A significant difference (P<0.001) of B. sulcata infection was recorded in diarrhoeic (54.7%) and non-diarrhoeic (14.0%) animals. However, the intensity of infection was recorded higher in diarrhoeic than non-diarrhoeic animals. Moreover, a significantly (P<0.001) higher incidence of other gastrointestinal (GI) parasites were recorded in non-diarrhoeic (30.0%) animals with very low intensity of infection. Only small number of diarrhoeic animals showed B. sulcata infection along with other parasite i.e., mix infection (5.7%) whereas, no mix infections were recorded in non-diarrhoeic animals. The incidence of B. sulcata infection in older animals (33.3%) was higher than young (18.2%) and adult (33.3%) animals. Similarly, incidence of B. sulcata infection in winter was recorded highest (43.8%) followed by monsoon (31.0%) and summer (31.0%). Statistically, no significant difference (P>0.05) was observed among the different season and age groups of animals. The present study demonstrated the higher incidence of B. sulcata infection in Jaffrabadi buffalo which is having problem of frequent diarrhoea
Toward a geography of black internationalism: Bayard Rustin, nonviolence and the promise of Africa
This article charts the trip made by civil rights leader Bayard Rustin to West Africa in 1952, and examines the unpublished ‘Africa Program’ which he subsequently presented to leading American pacifists. I situate Rustin’s writings within the burgeoning literature on black internationalism which, despite its clear geographical registers, geographers themselves have as yet made only a modest contribution towards. The article argues that within this literature there remains a tendency to romanticize cross-cultural connections in lieu of critically interrogating their basic, and often competing, claims. I argue that closer attention to the geographies of black internationalism, however, allows us to shape a more diverse and practiced sense of internationalist encounter and exchange. The article reconstructs the multiplicity of Rustin’s black internationalist geographies which drew eclectically from a range of Pan-African, American and pacifist traditions. Though each of these was profoundly racialized, they conceptualized race in distinctive ways and thereby had differing understandings of what constituted the international as a geographical arena. By blending these forms of internationalism Rustin was able to promote a particular model of civil rights which was characteristically internationalist in outlook, nonviolent in principle and institutional in composition; a model which in selective and uneven ways continues to shape our understanding of the period
British Black Power:The anti-imperialism of political blackness and the problem of nativist socialism
The history of the US Black Power movement and its constituent groups such as the Black Panther Party has recently gone through a process of historical reappraisal, which challenges the characterization of Black Power as the violent, misogynist and negative counterpart to the Civil Rights movement. Indeed, scholars have furthered interest in the global aspects of the movement, highlighting how Black Power was adopted in contexts as diverse as India, Israel and Polynesia. This article highlights that Britain also possessed its own distinctive form of Black Power movement, which whilst inspired and informed by its US counterpart, was also rooted in anti-colonial politics, New Commonwealth immigration and the onset of decolonization. Existing sociological narratives usually locate the prominence and visibility of British Black Power and its activism, which lasted through the 1960s to the early 1970s, within the broad history of UK race relations and the movement from anti-racism to multiculturalism. However, this characterization neglects how such Black activism conjoined explanations of domestic racism with issues of imperialism and global inequality. Through recovering this history, the article seeks to bring to the fore a forgotten part of British history and also examines how the history of British Black Power offers valuable lessons about how the politics of anti-racism and anti-imperialism should be united in the 21st century.</p
Modifying effect of dual antiplatelet therapy on incidence of stent thrombosis according to implanted drug-eluting stent type
Aim To investigate the putative modifying effect of dual antiplatelet therapy (DAPT) use on the incidence of stent thrombosis at 3 years in patients randomized to Endeavor zotarolimus-eluting stent (E-ZES) or Cypher sirolimus-eluting stent (C-SES). Methods and results Of 8709 patients in PROTECT, 4357 were randomized to E-ZES and 4352 to C-SES. Aspirin was to be given indefinitely, and clopidogrel/ticlopidine for ≥3 months or up to 12 months after implantation. Main outcome measures were definite or probable stent thrombosis at 3 years. Multivariable Cox regression analysis was applied, with stent type, DAPT, and their interaction as the main outcome determinants. Dual antiplatelet therapy adherence remained the same in the E-ZES and C-SES groups (79.6% at 1 year, 32.8% at 2 years, and 21.6% at 3 years). We observed a statistically significant (P = 0.0052) heterogeneity in treatment effect of stent type in relation to DAPT. In the absence of DAPT, stent thrombosis was lower with E-ZES vs. C-SES (adjusted hazard ratio 0.38, 95% confidence interval 0.19, 0.75; P = 0.0056). In the presence of DAPT, no difference was found (1.18; 0.79, 1.77; P = 0.43). Conclusion A strong interaction was observed between drug-eluting stent type and DAPT use, most likely prompted by the vascular healing response induced by the implanted DES system. These results suggest that the incidence of stent thrombosis in DES trials should not be evaluated independently of DAPT use, and the optimal duration of DAPT will likely depend upon stent type (Clinicaltrials.gov number NCT00476957
Identification, Evaluation and Utilization of Resistance to Insect Pests in Grain Legumes: Advancement and Restrictions
The 68th session of the UN General Assembly declared 2016 as the International Year of Pulses (IYP 2016), emphasizing the nutritional significance of legumes and their potential role for achieving global food security. Even though the IYP ended with enhanced public awareness about the nutritional aspects, other health benefits, and importance of mitigating climate change, and its role in promoting biodiversity, additional studies are required to increase the global production and trade of pulses. Major food legumes including chickpea, pigeonpea, cowpea, field pea, lentil, faba bean, black gram, green gram and Phaseolus beans play a vital role in food, nutritional security and sustainable crop production. Several insect pests damage grain legumes, of which Helicoverpa armigera; Maruca vitrata; Etiella zinckenella; Spodoptera litura and S. exigua; Melanagromyza obtusa; Ophiomyia phaseoli; Aphis craccivora and Bemisia tabaci; Empoasca spp., Megaleurothrips dorsalis and Caliothrips indicus; Mylabris spp.; and Callosobruchus chinensis cause extensive losses. Appreciable progress has been made in formulating screening techniques to evaluate germplasm, mapping populations and genetically modified crops for resistance to insect pests under field and greenhouse conditions. However, some of these techniques cannot be used for stem flies, pod fly, leafhoppers, thrips and aphids. There is a need to develop rearing protocols for such insects to undertake precise phenotyping studies.
The indiscriminate use of insecticides has resulted in the development of insecticide resistance in pests. Identification and utilization of genetic sources of resistance is one of the eco-friendly approaches for the management of insect pests. There is a need to identify lines with diverse mechanisms of resistance and to develop insect resistant cultivars by diversifying the genetic variability utilizing the wild accessions of chickpea, pigeonpea and cowpea, which can be exploited for introgressions to enhance the levels of resistance to pod borers to build host plant resistance as an viable component of pest management in grain legumes for sustainable crop production
A Decolonial Critique of the Racialized “Localwashing” of Extraction in Central Africa
Responding to calls for increased attention to actions and reactions “from above” within the extractive industry, we offer a decolonial critique of the ways in which corporate entities and multinational institutions draw on racialized rhetoric of “local” suffering, “local” consultation, and “local” culpability in oil as development. Such rhetoric functions to legitimize extractive intervention within a set of practices that we call localwashing. Drawing from a decade of research on and along the Chad–Cameroon Oil Pipeline, we show how multiscalar actors converged to assert knowledge of, responsibility for, and collaborations with “local” people within a racialized politics of scale. These corporate representations of the racialized “local” are coded through long-standing colonial tropes. We identify three interrelated and overlapping flexian elite rhetoric(s) and practices of racialized localwashing: (1) anguishing, (2) arrogating, and (3) admonishing. These elite representations of a racialized “local” reveal diversionary efforts “from above” to manage public opinion, displace blame for project failures, and domesticate dissent in a context of persistent scrutiny and criticism from international and regional advocates and activists
Evaluation of the effect of different Dates of Sowing Regimes in Chickpea against Legume Pod Borer, Helicoverpa armigera (Hubner)
Effect of different sowing dates on chickpea crop and varietal factors against the incidence of legume pod borer Helicoverpa armigera, pod damage and yield were studied at the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, Hyderabad, Telangana during the post rainy seasons of 2019-20, and 2020-21. Ten Chickpea genotypes were sown at monthly intervals during first weeks of September, October and November. Each entry was sown in a 6 row plots, with 10 x 30 cm spacing. There were four replications in a split plot design. Among the different sowing regimes tested, November sown crop was found to be optimal and right time for sowing of the chickpea genotype to evade the pod borer coincidence. The borer population fluctuated with the change in dates of sowing. Pod borer population was higher in the early sown crop (September) and with delayed dates of sowing in October and November population decreased. There were significant differences in percent pod damage across genotypes ranging from 10.50 to 40.66 per cent. Minimum pod damage was observed in ICCV 10
and maximum pod damage was observed in ICC 3137. The grain yield ranged from 316.4 kg/ha to 836.1 kg/ha. The highest grain yield was recorded in ICCV 10 and lowest in ICC 3137. Correlation results of pod borer incidence in ICC 3137 showed positive correlation with maximum, minimum temperature and solar radiation, while rainfall and humidity were negatively correlated. Screening the different chickpea
genotypes for resistance or tolerance to H. armigera allowed us in detection of a resistant/tolerant varieties which has shown the minimum level of damage in pods and further for ensuring higher yield with less pod borer damage, November is the optimal time for sowing of Chickpea
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