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Crystal structure analysis of a pyrazole carboxylic acid derivative, 5-(trifluoromethyl)-1-phenyl-1H-pyrazole-4-carboxylic acid (1) has been carried out from laboratory powder X-ray diffraction data. The crystal packing in the pyrazole carboxylic acid derivative exhibits an interplay of strong O–H…O, C–H…N and C–H…F hydrogen bonds to generate a three-dimensional molecular packing via the formation of R22(8) and R22(9) rings. Molecular electrostatic potential calculations indicated that carbonyl oxygen, pyrazole nitrogen and fluorine atoms to be the strongest acceptors. The relative contribution of different interactions to the Hirshfeld surface of pyrazole carboxylic acid and a few related structures retrieved from CSD indicates that H…H, N…H and O…H interactions can account for almost 70% of the Hirsfeld surface area in these compounds.
Rubella virus infection typically presents as a mild illness in children; however, infection during pregnancy may cause the birth of an infant with congenital rubella syndrome (CRS). As of February 2017, India began introducing rubella-containing vaccine (RCV) into the public-sector childhood vaccination programme. Low-level RCV coverage among children over several years can result in an increase in CRS incidence by increasing the average age of infection without sufficiently reducing rubella incidence. We evaluated the impact of RCV introduction on CRS incidence across India's heterogeneous demographic and epidemiological contexts. We used a deterministic age-structured model that reflects Indian states’ rural and urban area-specific demography and vaccination coverage levels to simulate rubella dynamics and estimate CRS incidence with and without RCV introduction to the public sector. Our analysis suggests that current low-level private-sector vaccination has already slightly increased the burden of CRS in India. We additionally found that the effect of public-sector RCV introduction depends on the basic reproductive number, R0, of rubella. If R0 is five, a value empirically estimated from an array of settings, CRS incidence post-RCV introduction will likely decrease. However, if R0 is seven or nine, some states may experience short-term or annual increases in CRS, even if a long-term total reduction in cases (30 years) is expected. Investment in population-based serological surveys and India's fever/rash surveillance system will be key to monitoring the success of the vaccination programme.
Protection-based ant–plant mutualisms may vary in strength due to differences in ant rewards, abundance of protective ants and herbivory pressure. We investigated geographical and temporal variation in host plant traits and herbivory pressure at five sites spanning the distribution range of the myrmecophyte Humboldtia brunonis (Fabaceae) in the Indian Western Ghats. Southern sites had, on average, 2.4 times greater abundance of domatia-bearing individuals, 1.6 times greater extrafloral nectary numbers per leaf, 1.2 times larger extrafloral nectary sizes, 2.2 times greater extrafloral nectar (EFN) volumes and a two-fold increase in total amino acid and total sugar concentrations in EFN compared with northern sites. A strong protection-based mutualism with ants occurred at only one southern site where herbivory was highest, suggesting that investments in attracting ants correlate with anti-herbivore benefits gained from the presence of protective ants. Our results confirm a temporally stable north–south gradient in myrmecophytic traits in this ant-plant as several of these traits were re-sampled after a 5-y interval. However, the chemical composition of EFN varied at both spatial and short-term temporal scales suggesting that only repeated measurements of rewards such as EFN can reveal the real spectrum of trait variation in an ant–plant mutualistic system.
As the interconnect RC delay plays an increasingly dominant role in the performance of deep submicron ULSI devices, Cu and low-k dielectric materials are deemed necessary to replace the traditional Al and SiO2 system to lower both the resistance and capacitance of metallization. This paper presents a systematic simulation method to assess the impact of Cu and low-k dielectric to the system speed and cross-talk noise for 0.18-μm design rules (0.6 μm pitch), and determine the practical process windows for metal line aspect ratio and the structural configuration of dielectrics. It was found that the high performance requirements for 0.18-μm devices (600 MHz and cross-talk <0.3 on a 2×2 cm2 chip) cannot be met by simply replacing Al with Cu or SiO2 with low-k dielectric (k=3), without any change in the interconnect architecture. By reverse scaling the metal pitch to 2× at upper levels, on the other hand, one can easily find a manufacturable process window, even with the Al and SiO2 system. Case studies on R and C of various structural configurations and boundary conditions have been performed, including Cu barrier layer thickness, metal gap fill and capping layer thickness of low-k dielectrics, as well as the influence of the lower and upper metal plates. The significance of the results on the strategy of implementing Cu/low-k interconnects versus extending Al/SiO2 will be discussed.
Kheraiceras Spath, 1924, is known mainly from macroconchs. Matching of dimorphic pairs at species level is difficult due to the rarity of microconchs and consequent difficulty in establishing contemporaneity. The present study reveals dimorphism within Kheraiceras cosmopolitum (Parona and Bonarelli, 1895) from the lower part of the Callovian Chari Formation, Kutch, India, where microconch closely resembles macroconch except for the size, being about three times smaller and having an aperture characterized by terminal construction. The evolution of Kheralceras from Bullatimorphites Buckman is based on macroconchs only. The discovery of coeval microconch specimens and study of known microconchs within the lineage indicate “parallel” evolution in macro- and microconchs and improves the understanding of evolutionary trends that involve complex heterochronic processes.
A novel method has been devised to extract poly (A+)RNA from seed tissues. The advantages of this technique include the speed of extraction and the elimination of the hazardous phenol:chloroform extraction step which usually precedes oligo (dT)-cellulose column chromatography. Instead, the crude supernatant, containing a high concentration of SDS and salts to effectively inhibit RNase activity, is passed directly over the oligo (dT)-cellulose column. The resultant isolated poly (A+)RNA is of high yield and purity and is suitable for in vitro translation and Northern blot analysis.
The problem of capillary–gravity waves generated by certain moving oscillatory surface-pressure distributions is investigated. The main difficulty of the problem lies in finding the real roots of the modified frequency equations. This is dealt with by the use of certain geometric considerations. The critical condition that results from the formation of double roots of the modified frequency equations is represented as a surface. This surface divides the whole space into several distinct regions. For points in different regions the propagation of waves is different. The waves are determined in all cases.
The initial-value problem of waves generated by a moving oscillatory surface pressure against a vertical cliff is solved and a uniform asymptotic analysis of the unsteady state is given. The same problem with no cliff is solved by Kaplan, and by Debnath and Rosenblat but their solutions are not uniform.
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