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Differences in root morphology and acclimation to low‐phosphorus (P) soil were examined among eight legume species from the Trifolium Section Tricocephalum to understand how these root attributes determine P acquisition. Ornithopus sativus was included as a highly P‐efficient benchmark species. Plants were grown as microswards in pots with five rates of P supplied in a topsoil layer to mimic uneven P distribution within a field soil profile. Topsoil and subsoil roots were harvested separately to enable measurement of the nutrient‐foraging responses. Critical P requirement (lowest P supply for maximum yield) varied over a threefold range, reflecting differences in root morphology and acclimation of nutrient‐foraging roots to P stress. Among the species, there was a 3.2‐fold range in root length density, a 1.7‐fold range in specific root length, and a 2.1‐fold range in root hair length. O. sativus had the lowest critical P requirement, displayed a high root length density, the highest specific root length, and the longest root hairs. Acquisition of P from P‐deficient soil was facilitated by development of a large root hair cylinder (i.e. a large root–soil interface). This, in turn, was determined by the intrinsic root morphology attributes of each genotype, and the plasticity of its root morphology response to internal P stress. Root acclimation in low‐P soil by all species was mostly associated with preferential allocation of mass to nutrient‐foraging roots. Only O. sativus and four of the Trifolium species adjusted specific root length beneficially, and only O. sativus increased its root hair length in low‐P soil. [ABSTRACT FROM AUTHOR]

Second SARS-CoV-2 infections twelve months after initial infections in Australia, confirmed by genomic analysis Keywords: COVID-19 EN COVID-19 199 201 3 03/11/22 20220301 NES 220301 Second infections with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are thought to affect fewer than 1% of people with resolved coronavirus disease 2019 (COVID-19).1 Reinfections as soon as 26 days after the initial diagnosis have been reported, in some cases with increased disease severity.1,2 No confirmed cases of second SARS-CoV-2 infections have been reported in Australia, but public awareness of the possibility is needed to encourage continued testing and vaccination. All three patients had also been diagnosed with COVID-19 in July 2020, during a period of high community transmission in Victoria; the source of these earlier infections was unknown. [Extracted from the article]

Abstract: Sum‐accelerated pseudospectral methods herein are used to describe the kinetic energy matrix within density functional theory descriptions of few‐atom systems. The resulting energies are compared to the conventional finite difference results. It is demonstrated that the sum‐acceleration allows for significantly improved scaling with respect to the grid step size and matrix bandwidth while maintaining a computational speed equivalent with that of the finite difference description. In addition, analytical expressions for the pseudopotential matrix elements are introduced to alleviate the eggbox effect—the dependence of the energy on the relative position of the atoms and grid points. [ABSTRACT FROM AUTHOR]

Background and aims: The growth and root morphology responses to soil phosphorus (P) fertility by five cultivars of Trifolium subterraneum (a temperate annual pasture legume) were examined to assess whether differences in root morphology and/or root acclimation to P stress influenced P-acquisition by the clover varieties, or their critical P requirements (i.e. the rate of P supply needed for maximum shoot yield).Methods: The clovers were grown as microswards in soil with P stratified in a topsoil layer to mimic growth conditions and soil P availability in a pasture. Yield and P content of shoots, and roots from the topsoil and subsoil layers was determined after 5 weeks growth in a controlled-environment cabinet. The lengths, diameters, and root hair lengths of nutrient foraging roots from the topsoil layer were quantified.Results: The shoot yield of the cultivars was similar when grown with high soil P fertility. However, the cultivars varied up to 1.5-fold in their ability to yield at low levels of soil P supply, and by 1.6-fold in their critical P requirements. All cultivars acclimated to low P soil by increasing root length density in the topsoil but those that yielded relatively well did so by maintaining a large root hair cylinder volume (i.e. they explored more soil) under low soil P conditions. This was associated with maintenance of dry matter allocations to topsoil roots and higher specific root lengths. Both factors assisted development of high root length density for nutrient foraging. Root acclimation responses to P were compared among the cultivars at equivalent relative shoot yields to assess the influence of plant P stress as a trigger for nutrient foraging. The least P-efficient cultivars slowed their allocation of dry matter to foraging roots at lower levels of P stress.Conclusions: The results suggest variation within T. subterraneum for root proliferation and specific root length could be targeted in breeding for improved P-acquisition efficiency. [ABSTRACT FROM AUTHOR]

In the article, the author offers information on treatment of Hispanic American clergies and religious heads. The author mentions the importance of language as part of cultural sensitivity for providing proper treatment to a specialized population of task force run by heads consisting of reverend Eduardo Nevares, sister Miriam Perez and reverend Antonio Flore. It cites various cultures including the Latino cultures where interpersonal relationship is given the utmost importance.

Taking a calculated risk on reorganizing its treatment approach appears to have turned this center around Although the influence of managed care is usually viewed by treatment centers as a [...]