Network Marketing on a Small-World Network

We investigate a dynamic model of network marketing in a small-world network structure artificially constructed similarly to the Watts-Strogatz network model. Different from the traditional marketing, consumers can also play the role of the manufacturer's selling agents in network marketing, which is stimulated by the referral fee the manufacturer offers. As the wiring probability $\alpha$ is increased from zero to unity, the network changes from the one-dimensional regular directed network to the star network where all but one player are connected to one consumer. The price $p$ of the product and the referral fee $r$ are used as free parameters to maximize the profit of the manufacturer. It is observed that at $\alpha=0$ the maximized profit is constant independent of the network size $N$ while at $\alpha \neq 0$, it increases linearly with $N$. This is in parallel to the small-world transition. It is also revealed that while the optimal value of $p$ stays at an almost constant level in a broad range of $\alpha$, that of $r$ is sensitive to a change in the network structure. The consumer surplus is also studied and discussed.Comment: 12 pages, to appear in Physica

What’s the Big Deal about Statins?

Statins are a group of cholesterol-lowering medications that have been shown evidence to be beneficial for tens of millions of Americans. Some examples of statin medications you may have heard of include: atorvastatin (Lipitor), rosuvastatin (Crestor), simvastatin (Zocor), pravastatin (Pravachol) and lovastatin (Mevacor). Statins are one of the most commonly prescribed medications in the United States. One in four adults over the age of 45 years old are currently taking a statin for its many benefits. See below for more information about its use

Simulation of Primordial Black Holes with large negative non-Gaussianity

In this work, we have performed numerical simulations of primordial black hole (PBH) formation in the Friedman-Lema\^itre-Robertson-Walker universe filled by radiation fluid, introducing the local-type non-Gaussianity to the primordial curvature fluctuation. We have compared the numerical results from simulations with previous analytical estimations on the threshold value for PBH formation done in the previous paper arXiv:2109.00791, particularly for negative values of the non-linearity parameter $f_{\rm NL}$. Our numerical results show the existence of PBH formation of (the so-called) type I also in the case $f_{\rm NL} \lesssim -0.336$, which was not found in the previous analytical expectations using the critical averaged compaction function. In particular, although the universal value for the averaged critical compaction function $\bar{\mathcal{C}}_{c}=2/5$ found previously in the literature is not satisfied for all the profiles considered in this work, an alternative direct analytical estimate has been found to be roughly accurate to estimate the thresholds, which gives the value of the critical averaged density with a few $\%$ deviation from the numerical one for $f_{\rm NL}\gtrsim -1$.Comment: 20 pages, 9 figures. v2: minor changes. Accepted for publication in JCA

Phylogenetic diversification of glycogen synthase kinase 3/SHAGGY-like kinase genes in plants

BACKGROUND: The glycogen synthase kinase 3 (GSK3)/SHAGGY-like kinases (GSKs) are non-receptor serine/threonine protein kinases that are involved in a variety of biological processes. In contrast to the two members of the GSK3 family in mammals, plants appear to have a much larger set of divergent GSK genes. Plant GSKs are encoded by a multigene family; analysis of the Arabidopsis genome revealed the existence of 10 GSK genes that fall into four major groups. Here we characterized the structure of Arabidopsis and rice GSK genes and conducted the first broad phylogenetic analysis of the plant GSK gene family, covering a taxonomically diverse array of algal and land plant sequences. RESULTS: We found that the structure of GSK genes is generally conserved in Arabidopsis and rice, although we documented examples of exon expansion and intron loss. Our phylogenetic analyses of 139 sequences revealed four major clades of GSK genes that correspond to the four subgroups initially recognized in Arabidopsis. ESTs from basal angiosperms were represented in all four major clades; GSK homologs from the basal angiosperm Persea americana (avocado) appeared in all four clades. Gymnosperm sequences occurred in clades I, III, and IV, and a sequence of the red alga Porphyra was sister to all green plant sequences. CONCLUSION: Our results indicate that (1) the plant-specific GSK gene lineage was established early in the history of green plants, (2) plant GSKs began to diversify prior to the origin of extant seed plants, (3) three of the four major clades of GSKs present in Arabidopsis and rice were established early in the evolutionary history of extant seed plants, and (4) diversification into four major clades (as initially reported in Arabidopsis) occurred either just prior to the origin of the angiosperms or very early in angiosperm history

Health economic impact of first-pass success among patients with acute ischemic stroke treated with mechanical thrombectomy: a United States and European perspective

Economics; Stroke; ThrombectomyEconomia; Ictus; TrombectomiaEconomía; Ictus; TrombectomíaBackground First-pass effect (FPE), restoring complete or near complete reperfusion (modified Thrombolysis in Cerebral Infarction (mTICI) 2c-3) in a single pass, is an independent predictor for good functional outcomes in the endovascular treatment of acute ischemic stroke. The economic implications of achieving FPE have not been assessed. Objective To assess the economic impact of achieving complete or near complete reperfusion after the first pass. Methods Post hoc analyses were conducted using ARISE II study data. The target population consisted of patients in whom mTICI 2c–3 was achieved, stratified into two groups: (1) mTICI 2c–3 achieved after the first pass (FPE group) or (2) after multiple passes (non-FPE group). Baseline characteristics, clinical outcomes, and healthcare resource use were compared between groups. Costs from peer-reviewed literature were applied to assess cost consequences from the perspectives of the United States (USA), France, Germany, Italy, Spain, Sweden, and United Kingdom (UK). Results Among patients who achieved mTICI 2c–3 (n=172), FPE was achieved in 53% (n=91). A higher proportion of patients in the FPE group reached good functional outcomes (90-day modified Rankin Scale score 0–2 80.46% vs 61.04%, p<0.01). The patients in the FPE group had a shorter mean length of stay (6.10 vs 9.48 days, p<0.01) and required only a single stent retriever, whereas 35% of patients in the non-FPE group required at least one additional device. Driven by improvement in clinical outcomes, the FPE group had lower procedural/hospitalization-related (24–33% reduction) and annual care (11–27% reduction) costs across all countries. Conclusions FPE resulted in improved clinical outcomes, translating into lower healthcare resource use and lower estimated costs.This study was funded by Cerenovus, a subsidiary of Johnson and Johnson

Benchmarking the Extent and Speed of Reperfusion: First Pass TICI 2c-3 Is a Preferred Endovascular Reperfusion Endpoint

Isquèmia cerebral; Trombectomia mecànica; ReperfusióIsquemia cerebral; Trombectomía mecánica; ReperfusiónBrain ischaemia; Mechanical thrombectomy; ReperfusionBackground and Purpose: End-of-procedure substantial reperfusion [modified Treatment in Cerebral Ischemia (mTICI) 2b-3], the leading endpoint for thrombectomy studies, has several limitations including a ceiling effect, with recent achieved rates of ~90%. We aimed to identify a more optimal definition of angiographic success along two dimensions: (1) the extent of tissue reperfusion, and (2) the speed of revascularization. Methods: Core-lab adjudicated TICI scores for the first three passes of EmboTrap and the final all-procedures result were analyzed in the ARISE II multicenter study. The clinical impact of extent of reperfusion and speed of reperfusion (first-pass vs. later-pass) were evaluated. Clinical outcomes included 90-day functional independence [modified Rankin Scale (mRS) 0–2], 90-day freedom-from-disability (mRS 0–1), and dramatic early improvement [24-h National Institutes of Health Stroke Scale (NIHSS) improvement ≥ 8 points]. Results: Among 161 ARISE II subjects with ICA or MCA M1 occlusions, reperfusion results at procedure end showed substantial reperfusion in 149 (92.5%), excellent reperfusion in 121 (75.2%), and complete reperfusion in 79 (49.1%). Reperfusion rates on first pass were substantial in 81 (50.3%), excellent reperfusion in 62 (38.5%), and complete reperfusion in 44 (27.3%). First-pass excellent reperfusion (first-pass TICI 2c-3) had the greatest nominal predictive value for 90-day mRS 0–2 (sensitivity 58.5%, specificity 68.6%). There was a progressive worsening of outcomes with each additional pass required to achieve TICI 2c-3. Conclusions: First-pass excellent reperfusion (TICI 2c-3), reflecting rapid achievement of extensive reperfusion, is the technical revascularization endpoint that best predicted functional independence in this international multicenter trial and is an attractive candidate for a lead angiographic endpoint for future trials.Cerenovus sponsored the ARISE II study, and provided support for open access to this article

Clinical Outcome after Intra-Arterial Stroke Therapy in the Very Elderly: Why is it so Heterogeneous?

Very elderly patients (i.e., ≥80 years) are disproportionally affected by acute ischemic stroke. They account for a third of hospital stroke admissions, but two-thirds of overall stroke-related morbidity and mortality. There is some evidence of clinical benefit in treating selected very elderly patients with intravenous thrombolysis (IVT). For very elderly patients ineligible or non-responsive to IVT, intra-arterial therapy (IAT) may have promise in improving clinical outcome. However, its unequivocal efficacy in the general population remains to be proven in randomized trials. Small cohort studies reveal that the rate of good clinical outcome for very elderly patients after IAT is highly variable, ranging from 0 to 28%. In addition, they experience higher rates of futile reperfusion than younger patients. Thus, it is imperative to understand the factors that impact on clinical outcome in very elderly patients after IAT. The aim of this review is to examine the factors that may be responsible for the heterogeneous clinical response of the very elderly to IAT. This will allow the reader to integrate the current available evidence to individualize intra-arterial stroke therapy in very elderly patients. Placing emphasis on pre-stroke independent living, smaller infarct core size, short procedure times, and avoiding general anesthesia where feasible, will help improve rates of good clinical outcome