Effects of Fragmentation and the Case for Greater Cohesion in Neurologic Care Delivery

Goals:To define fragmentation in neurological care delivery; explain the positive and negative drivers in neurologic practice that contribute to fragmentation; illustrate situations that increase fragmentation risk; emphasize the costs and impact on both patients and providers; propose solutions that allow for more cohesive care.Work group:The Transforming Leaders Program (TLP) class of 2020 was tasked by American Academy of Neurology (AAN) leadership to identify the leading trends in inpatient and outpatient neurology and to predict their effects on future neurologic practice.Methods:Research material included AAN data bases, PubMed searches, discussion with topic experts and AAN leadership.Results:Trends in care delivery are driven by changes in the work force, shifts in health care delivery, care costs, changes in evidence-based care and patient factors. These trends can contribute to care fragmentation. Potential solutions to these problems are proposed based on care models developed in oncology and medicine.Limitations:This paper shares our opinions as there is a lack of evidence-based guidelines as to optimal neurological care delivery.

Decay Analysis of 197Tl* Compound Nucleus Formed in 16O + 181Ta Reaction at above Barrier Energy Ec.m.~100 MeV

The decay dynamics of 197Tl* compound nucleus has been studied within the framework of the dynamical cluster-decay model (DCM) at above barrier energy Ec.m. ≈ 100 MeV using quadrupole deformed configuration of decay fragments. The influence of various nuclear radius parameters on the decay path and mass distributions has been investigated by analysing the fragmentation potential and preformation probability. It is observed that 197Tl* nucleus exhibits the triple-humped mass distribution, independent of nuclear radius choice. The most preferred fission fragments of both fission modes (symmetric and asymmetric) are identified, which lie in the neighborhood of spherical and deformed magic shell closures. Moreover, the modification in the barrier characteristics, such as interaction barrier and interaction radius, is observed with the variation in the radius parameter of decaying fragments and influences the penetrability and fission cross-sections. Finally, the fission cross-sections are calculated for considered choices of nuclear radii, and the results are compared with the available experimental data.

Effect of Oriented Nuclei on the Competing Modes of α and One-Proton Radioactivities in the Vicinity of Z = 82 Shell Closure

The purpose of the present work is to investigate the alpha (α) emission as competing mode of one proton emission using the preformed cluster decay model (PCM). PCM is based on the quantummechanical tunneling mechanism of penetration of the preformed fragments through a potential barrier, calculated within WKB approximation. To explore the competing aspects of α and one proton radioactivity, we have chosen emitters present immediately above and below the Z = 82 shell closure i.e. 177Tl and 185Bi by taking into account the effects of deformations (β2) and orientations of outgoing nuclei. The minimized values of fragmentation potential and maximized values of preformation probability (P0) for proton and alpha fragment demonstrated the crucial role played by even Z - even N daughter and shell closure effect of Z = 82 daughter, in 177Tl and 185Bi, respectively. The higher values of P0 of the one proton further reveal significance of nuclear structure in the proton radioactivity. From the comparison of proton and α decay, we see that the former is heavily dominating with larger values of P0 in comparison to the later. Theoretically calculated half-lives of one proton and α emission for spherical and deformed considerations have also been compared with available experimental data.

Enhanced Fission Probability of Even-Z Fragments in the Decay of Hot and Rotating 210Rn* Compound System

Mass and charge distribution of the cross-section for the fission fragments obtained in the decay of hot and rotating compound system formed in the reaction 48Ca + 162Dy → 210Rn* at an incident energy 139.6 MeV has been calculated using the dynamical cluster-decay model. Isotopic composition for each element belonging to the symmetric mass region has been obtained. The shell closure at N=50 for light and at Z=50 for heavy mass binary fragments gives a deep minima in the fragmentation potential at touching configuration and governs the fission partition of the compound system. The fission fragments of the symmetric mass region have their dominating presence along with strong odd-even staggering i.e., even-Z fission fragments are more probable than the odd ones, similar to the observed trends of the yield.

Directed homoenzymatic fragmentation of the plant protopectin complex: Assessment criteria

Introduction. The functional basis of protopectin complex can be represented as a network of regions that consist of homogalacturonan sequences and a base of rhamnogalacturonans-I, i.e. rhamnosyl-containing branching sites. Enzymatic isolation of these regions is possible only at a certain minimal native degree of polymerization. The research objective was to develop a system of criteria for assessing the potential applicability of the enzymatic transformation of plant protopectin complex. Study objects and methods. The research featured the polymerization degree of the homogalacturonan regions of the protopectin complex and produced a system of assessment criteria for the enzymatic fragmentation potential of the protopectin complex. The theoretical calculations were based on the values of the mass fractions of rhamnosyl and galacturonide residues in plant cell walls. The result was a new polymerization degree analytical function. Results and discussion. The ratio of the mass fractions of rhamnosyl and galacturonide residues in the water-insoluble plant tissue served as a dimensionless criterion of applicability. The rational condition for the dimensionless criterion of applicability was based on the fundamental constraint for homogalacturonan regions in the protopectin complex. It was expressed by a fundamental inequation. The rational area for determining the numerical values of the applicability criterion was presented as . The functional dependence was reduced to a two-dimensional criteria space as “width of rhamnosyl branches vs. the criterion of applicability”, where each pectin-containing raw material was given a single uniquely defined position. The boundary conditions for the criteria space were determined analytically. Conclusion. The new approach offers an assessment of the enzymatic fragmentation potential of the plant protopectin complex by homoenzyme preparations. The approach is in fact the second stage of the decision tree in the science-based technology for pectin and its products.

Systematic study of alpha-decay of super-heavy isotopes with Z = 120–126

Alpha-decay half-lives of the even–even superheavy isotopes with proton numbers [Formula: see text] have been calculated within the cluster model. The alpha-daughter potential was constructed by employing the density-dependent double-folding model with a realistic nucleon–nucleon interaction whose exchange part has a finite range approximation. The half-lives were calculated using Wentzel–Kramers–Brillouin (WKB) approximation with the alpha preformation factor. The results have shown that the computed alpha-decay half-lives were in good agreement with their counterpart calculated by different semi-empirical approaches. The obtained results have also shown a negative linear relationship between the logarithm of the preformation factor and the fragmentation potential for the understudy isotopes. Also, the calculated results have shown that isotopes [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] had longer half-lives than their adjacent isotopes, which indicates that the corresponding neutron or proton numbers have a magical or semi-magical properties. Furthermore, we have studied the competition between alpha-decay and spontaneous fission to predict possible decay modes from the even–even isotopes [Formula: see text]. The results revealed that the isotopes [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] had alpha-decay as a predominant mode of decay and the nuclei [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text] could not survive from the spontaneous fission. We hope that the theoretical prediction could be helpful for future investigation in this field.

Assessing protopectin transformation potential of plant tissue using a zoned criterion space

Introduction. The existing diversity of plant raw materials and products predetermine the prospects of studying their potential as sources of pectin substances. However all current classifications are either fragmented or inconsistent. Study objects and methods. Our theoretical ivestigation aimed to develop an adequate classification for all taxa of plant origin, as well as their tissues and derivatives as pectin-containing materials. We developed criteria for assessing transformation potential of the protopectin complex based on the mass fractions of biologically active non-uronide components, native water-soluble pectin, the protopectin complex, and pectin substances. Individual boundary conditions were based on individual pectin potential, protopectin fragmentation potential, and pectin isolation potential. Results and discussion. Based on the boundary conditions, we defined an universal criterion space that included a set of points M in the coordinates expressed by three main criteria. According to individual boundary conditions, the criterion space was divided, or zoned, into four domains corresponding to protopectin fragmentation potential. They were characterized by: 1) lack of pectin potential, 2) ineffective protopectin fragmentation, 3) ineffective isolation of fragmentation products, and 4) effective isolation. Finally, we developed a generalized algorithm to determine the location of points M[μ1, μ2 , μ3 ] in the zoned criterion space, characterizing the plant tissue. Conclusion. Our approach can be used to assess any plant tissue for its protopectin transformation potential, which determines the technological influence on its pectin potential. This approach is universal, i.e., applicable to both plant tissue and its derivatives.

Landscape genetics of Mexican biodiversity: A review

The rich biodiversity of Mexico is threatened due to habitat fragmentation and climate change. Landscape genetics provides an excellent framework that integrates genetic, geographic, and ecological landscape data to inform conservation strategies. To discuss the value of landscape genetics for the study of the Mexican biota, a literature review of landscape genetics studies in Mexico was conducted to highlight trends of taxonomic groups, habitats, and research objectives. A total of 20 studies were identified: 65% in plants and 35% in animals. A large proportion of studies focused on temperate ecosystems and tropical forests, whereas marine and urban environments were lacking. Detection of linear barriers and landscape features on gene flow were the most popular objectives, while two objectives were exclusive to plants: spatial adaptive variation and estimates of contemporary gene flow with parentage analyses to evaluate effects of habitat fragmentation. Potential areas of research for landscape genetics studies in Mexico and recommendations are discussed.

Quasifission mass distributions in the synthesis of 274Hs with 26Mg and 36S projectiles

The potential energy landscape for the [Formula: see text] synthesis is evaluated in the framework of the macroscopic–microscopic model. The fragmentation potential calculated in a configuration space characterized by five degrees of freedom associated to elongation, mass asymmetry, necking, and left/right deformations reveals the existence of several minima and some pronounced valleys. The valleys correspond mainly to the [Formula: see text] and [Formula: see text] quasifission channels, but also for some paths in the formation of the compound nuclear system. In this context, two different paths are obtained for the [Formula: see text] and [Formula: see text] entrance channels. The [Formula: see text] path leads to the formation of an isomeric minimum that decays by fission. The [Formula: see text] path evidences a larger probability for the formation of the compound nucleus. Therefore, the two distributions obtained for the associated quasifission processes are very different.