Deconstruction of the Trap Model for the New Conducting State in 2D

A key prediction of the trap model for the new conducting state in 2D is that the resistivity turns upwards below some characteristic temperature, $T_{\rm min}$. Altshuler, Maslov, and Pudalov have argued that the reason why no upturn has been observed for the low density conducting samples is that the temperature was not low enough in the experiments. We show here that $T_{\rm min}$ within the Altshuler, Maslov, and Pudalov trap model actually increases with decreasing density, contrary to their claim. Consequently, the trap model is not consistent with the experimental trends.Comment: Published version of Deconstructio

The Parallel Magnetoconductance of Interacting Electrons in a Two Dimensional Disordered System

The transport properties of interacting electrons for which the spin degree of freedom is taken into account are numerically studied for small two dimensional diffusive clusters. On-site electron-electron interactions tend to delocalize the electrons, while long-range interactions enhance localization. On careful examination of the transport properties, we reach the conclusion that it does not show a two dimensional metal insulator transition driven by interactions. A parallel magnetic field leads to enhanced resistivity, which saturates once the electrons become fully spin polarized. The strength of the magnetic field for which the resistivity saturates decreases as electron density goes down. Thus, the numerical calculations capture some of the features seen in recent experimental measurements of parallel magnetoconductance.Comment: 10 pages, 6 figure

Helianthus tuberosus and polyamine research: past and recent applications of a classical growth model

The earlieststudiesconcerningpolyamines(PAs)inplantswereperformedbyusing in vitro cultured explantsof Helianthustuberosus dormanttuber.Thisparenchymatissuewasparticularlyusefulduetoits susceptibility toseveralgrowthsubstances,includingPAs.Duringtuberdormancy,PAlevelsaretoolowto sustaincelldivision;thus Helianthus representsanaturalPA-deficient model.Whencultivated in vitro in the presenceofauxins, Helianthus tuber dormantparenchymacellsattheG0 stage starttodivide synchronously acquiringmeristematiccharacteristics.Therequirementforauxinstoinducecelldivision can besubstitutedbyaliphaticPAssuchasputrescine,spermidineorspermine.Cylindersorslicesof explantedhomogeneoustuberparenchymawereculturedinliquidmediumforshort-termstudiesonthe cell cycle,oronsolidagarmediumforlong-termexperiments.Morphologicalandphysiologicalmodificationsofsynchronouslydividingcellswerestudiedduringthedifferentphasesofthecellcycleinrelat on to PAsbiosynthesisandoxidation.Long-termexperimentsledtotheidentification ofthePAsasplant growthregulators,asthesolenitrogensource,astuberstoragesubstancesandasessentialfactorsfor morphogeneticprocessesandcellhomeostasis.Morerecentlythissystemwasusedtostudytheeffectson plant cellproliferationofplatinum-orpalladium-deriveddrugs(cisplatinandplatinumorpalladiumbi- substitutedspermine)thatareusedinhumancancercelllinesasantiproliferativeandcytotoxicagents. CisplatinwasthemostactivebothincellproliferationinhibitionandonPAmetabolism.Similarexperi- ments wereperformedusingthreeagmatineanalogous.Differenteffectsofthesecompoundswere observedoncellproliferation,freePAlevelsandenzymeactivities,leadingtoahypothesisofacorrelation between theirchemicalstructureandtheagmatinemetabolisminplant

Physicians' guideline adherence is associated with long-term heart failure mortality in outpatients with heart failure with reduced ejection fraction: the QUALIFY international registry

Background: Physicians' adherence to guideline-recommended therapy is associated with short-term clinical outcomes in heart failure (HF) with reduced ejection fraction (HFrEF). However, its impact on longer-term outcomes is poorly documented. Here, we present results from the 18-month follow-up of the QUALIFY registry. Methods and results: Data at 18 months were available for 6118 ambulatory HFrEF patients from this international prospective observational survey. Adherence was measured as a continuous variable, ranging from 0 to 1, and was assessed for five classes of recommended HF medications and dosages. Most deaths were cardiovascular (CV) (228/394) and HF-related (191/394) and the same was true for unplanned hospitalizations (1175 CV and 861 HF-related hospitalizations, out of a total of 1541). According to univariable analysis, CV and HF deaths were significantly associated with physician adherence to guidelines. In multivariable analysis, HF death was associated with adherence level [subdistribution hazard ratio (SHR) 0.93, 95% confidence interval (CI) 0.87–0.99 per 0.1 unit adherence level increase; P = 0.034] as was composite of HF hospitalization or CV death (SHR 0.97, 95% CI 0.94–0.99 per 0.1 unit adherence level increase; P = 0.043), whereas unplanned all-cause, CV or HF hospitalizations were not (all-cause: SHR 0.99, 95% CI 0.9–1.02; CV: SHR 0.98, 95% CI 0.96–1.01; and HF: SHR 0.99, 95% CI 0.96–1.02 per 0.1 unit change in adherence score; P = 0.52, P = 0.2, and P = 0.4, respectively). Conclusion: These results suggest that physicians' adherence to guideline-recommended HF therapies is associated with improved outcomes in HFrEF. Practical strategies should be established to improve physicians' adherence to guidelines. © 2019 The Authors. European Journal of Heart Failure © 2019 European Society of Cardiolog