Electronic transport mechanisms in a thin crystal of the Kitaev candidate α\alpha-RuCl3_3 probed through guarded high impedance measurements

$\alpha$-RuCl$_3$ is considered to be the top candidate material for the experimental realization of the celebrated Kitaev model. It is however known that additional interactions beyond the Kitaev model trigger in $\alpha$-RuCl$_3$, a long-range zigzag antiferromagnetic ground state. In this work, we investigate a nanoflake of $\alpha$-RuCl$_3$ through guarded high impedance measurements aimed at reaching through electronic transport, the regime where the system turns into a zigzag antiferromagnet. We investigated a variety of temperatures (\SI{1.45}{\kelvin} - \SI{175}{\kelvin}) and out-of-plane magnetic fields ranging up to \SI{11}{\tesla}. We found a clear signature of a structural phase transition at $\approx 160$\,K as reported for thin crystals of $\alpha$-RuCl$_3$, as well as a thermally activated behavior at temperatures above $\approx 30$\,K with a characteristic activation energy significantly smaller than the energy gap that we observe for $\alpha$-RuCl$_3$ bulk crystals through our Angle Resolved Photoemission Spectroscopy (ARPES) experiments. Additionally we found that below $\approx 30$\,K, transport is ruled by Efros-Shklovskii (ES) VRH. These observations point to the presence of Coulomb impurities in our thin crystals. Most importantly, our data shows that below the magnetic ordering transition known for bulk $\alpha$-RuCl$_3$ ($\approx 7$\,K), there is a clear deviation from VRH or thermal activation transport mechanisms. Our work demonstrates the possibility of reaching through specialized high impedance measurements, the thrilling ground states predicted for $\alpha$-RuCl$_3$ at low temperatures in the frame of the Kitaev model, and informs about the transport mechanisms in this material in a wide temperature range as well as on important characteristic quantities such as the localization length of the impurities in a thin $\alpha$-RuCl$_3$ crystal.Comment: 8 pages, 6 figures, Supplementary Material

Genetic architectures of proximal and distal colorectal cancer are partly distinct.

OBJECTIVE: An understanding of the etiologic heterogeneity of colorectal cancer (CRC) is critical for improving precision prevention, including individualized screening recommendations and the discovery of novel drug targets and repurposable drug candidates for chemoprevention. Known differences in molecular characteristics and environmental risk factors among tumors arising in different locations of the colorectum suggest partly distinct mechanisms of carcinogenesis. The extent to which the contribution of inherited genetic risk factors for CRC differs by anatomical subsite of the primary tumor has not been examined. DESIGN: To identify new anatomical subsite-specific risk loci, we performed genome-wide association study (GWAS) meta-analyses including data of 48 214 CRC cases and 64 159 controls of European ancestry. We characterised effect heterogeneity at CRC risk loci using multinomial modelling. RESULTS: We identified 13 loci that reached genome-wide significance (p<5×10-8) and that were not reported by previous GWASs for overall CRC risk. Multiple lines of evidence support candidate genes at several of these loci. We detected substantial heterogeneity between anatomical subsites. Just over half (61) of 109 known and new risk variants showed no evidence for heterogeneity. In contrast, 22 variants showed association with distal CRC (including rectal cancer), but no evidence for association or an attenuated association with proximal CRC. For two loci, there was strong evidence for effects confined to proximal colon cancer. CONCLUSION: Genetic architectures of proximal and distal CRC are partly distinct. Studies of risk factors and mechanisms of carcinogenesis, and precision prevention strategies should take into consideration the anatomical subsite of the tumour

Adoption of Macy Catheter by Aurora at Home hospice staff: A quality improvement evaluation study

Background: The Macy Catheter (MC) is a tool to aid rectal delivery of oral medications in microenemas. In 2019, Aurora Health at Home hospice chose the MC as a preferred route for delivery of medications when patients no longer tolerate the oral route. Despite training, adoption of the MC has been slow. Purpose: To determine what barriers exist to faster adoption and utilization of the MC by hospice nursing staff. It is anticipated that once the barriers are identified they will be addressed through a campaign of quality improvement projects with subsequent monitoring of adoption. Methods: An anonymous survey was given to 28 nurses at 2 meetings. The survey identified nurses that used the MC and their experiences. Nurses who had not used it were queried to see if they had no eligible patients or, if they had eligible patients, what their reasons were for not using it. Demographic data included age, experience as a registered nurse (RN) and hospice RN, usual shift worked, and work status. Basic descriptive statistics were used to describe the population. Results: Of a total of 28 surveys completed, 7 reflected use of the MC, with most using it only once and 1 using it 3–5 times. The number of medication doses given ranged from 1 to 10–20. There was an overall agreement regarding the ease of the MC insertion and its effectiveness when compared to the oral route. There were no complications noted. Ten nurses reported to never have used the MC because of not having eligible patients, while 12 reported having eligible patients and not using the MC, though 9 considered it. Common reasons for not using it include patient/family objections, inexperience using the MC, or confidence in other methods. One nurse reported not using it due to a nursing facility policy. Of those who had eligible patients and who did not consider using it, reasons given included unfamiliarity and not thinking of it in the “heat of the moment.” There were no demographic differences among these groups that would account for their willingness to use or consider the MC. Conclusion: The study identified leadership opportunities to increase the use of the Macy Catheter. Experienced nurses can help train and teach their peers how to “sell” this device to patients, families, and other clinicians. There is a need to develop educational collateral to help families understand the utility of the MC. We can work with facilities to make sure their policies align with the latest nursing approaches for excellent hospice care

Hidden biodiversity in cryptic habitats provided by porous coastal defence structures

In response to flood risk from rising and stormier seas, increasing amounts of natural coastline worldwide are being replaced by a proliferation of coastal defence structures. While the primary role of defence structures is protecting the coastline, consideration should be given to the biological coastal communities they support. Artificial structures are currently seen as poor habitats for marine organisms. They are constructed in harsh coastal environments, lack structural complexity, and are subjected to episodic disturbance from maintenance, reducing their suitability as habitats for coastal species. Recent work has focused on mitigating the impacts of coastal defence structures, through secondary routes such as enhancing biodiversity by encouraging colonisation of marine biota. Research thus far has focused on enhancements to improve structural complexity on the external surfaces of coastal defences. Many structures are porous with internal compartments. To date no work has been undertaken on the habitat provided by the internal surfaces of the blocks used in building structures.We investigated the role of porous coastal defence structures in habitat provision. Taking advantage of a groyne reduction from 45 m to 20 m length, we surveyed the internal environment of the structure. We also considered the impacts of maintenance activity on coastal assemblages. Our work shows that the internal environment of artificial structures provides functional habitat space supporting higher species richness and diversity than external surfaces. The more benign environment of internal surfaces protects from desiccation stress and is probably less scoured by mobile sediments, and as such is of unrealised importance to coastal assemblages. External surfaces are also subject to high levels of disturbance from maintenance activities, further limiting the potential ecological contribution this area of the artificial habitat might otherwise develop. These findings reveal the multifunctional role of porous coastal defence structures, acting as engineering protection and habitats for coastal assemblages

Periprocedural P2Y Inhibitors Improve Perioperative Outcomes After Carotid Stenting by Primarily Decreasing Strokes

OBJECTIVE: The continuation of antiplatelet agents in the periprocedural period around carotid stenting (CAS) procedures is felt to be mandatory to minimize the risk of periprocedural stroke. However, the optimal antiplatelet regimen is unclear, with some advocating dual antiplatelet therapy, and others supporting the use of P2Y inhibitors alone. The objective of this study was to evaluate the periprocedural effect of P2Y inhibitors for CAS. METHODS: The Vascular Quality Initiative was used from years 2007 to 2020. All transcarotid artery revascularization (TCAR) and transfemoral carotid artery stenting (TF-CAS) procedures were included. Patients were stratified based on perioperative use of P2Y inhibitors as well as symptomatic status. Primary end points were perioperative neurological events (strokes and transient ischemic attacks). Secondary end points were mortality and myocardial infarction. RESULTS: A total of 31,036 CAS procedures were included for analysis, with 49.8% TCAR and 50.2% TF-CAS cases; 63.8% of patients were male and 82.3% of patients were on a P2Y inhibitor. P2Y inhibitor use was more common in males, asymptomatic patients, those older than 70 years, and concurrent statin use. P2Y inhibitors were more likely to be used in TCAR cases than in TF-CAS cases (87.3% vs 76.8%; P \u3c .001). The rate of periprocedural neurological events in the whole cohort was 2.6%. Patients on P2Y inhibitors were significantly less likely to experience a periprocedural neurological event (2.3% vs 3.9%; P \u3c .001) and mortality (0.6% vs 2.1%; P \u3c .001) than those who were not on a P2Y inhibitor. There was no effect on the rates of myocardial infarction. On multivariate analysis, both symptomatic and asymptomatic patients on P2Y inhibitors were significantly less likely to develop perioperative neurological events. Additionally, the use of P2Y inhibitors demonstrated an independent significant effect in reducing of the rate of perioperative stroke (odds ratio, 0.29; 95% confidence interval, 0.25-0.33). Finally, additional analysis of the types of P2Y inhibitors used revealed that all seemed to be equally effective in decreasing the periprocedural neurological event rate. CONCLUSIONS: The use of perioperative P2Y inhibitors seems to markedly decrease the perioperative neurological event rate with TCAR and TF-CAS in both symptomatic and asymptomatic patients and should be strongly considered. Patients with contraindications to P2Y inhibitors may not be appropriate candidates for any CAS procedure. Additionally, alternative types of P2Y inhibitors seem to be equally effective as clopidogrel. Finally, an analysis of the Vascular Quality Initiative demonstrates that, even for TCAR cases, only 87.3% of patients seem to be on P2Y inhibitors in the periprocedural period, leaving room for significant improvement

Mortality risk in preterm and small-for-gestational-age infants in low-income and middle-income countries: a pooled country analysis.

BACKGROUND: Babies with low birthweight (<2500 g) are at increased risk of early mortality. However, low birthweight includes babies born preterm and with fetal growth restriction, and not all these infants have a birthweight less than 2500 g. We estimated the neonatal and infant mortality associated with these two characteristics in low-income and middle-income countries. METHODS: For this pooled analysis, we searched all available studies and identified 20 cohorts (providing data for 2,015,019 livebirths) from Asia, Africa, and Latin America that recorded data for birthweight, gestational age, and vital statistics through 28 days of life. Study dates ranged from 1982 through to 2010. We calculated relative risks (RR) and risk differences (RD) for mortality associated with preterm birth (<32 weeks, 32 weeks to <34 weeks, 34 weeks to <37 weeks), small-for-gestational-age (SGA; babies with birthweight in the lowest third percentile and between the third and tenth percentile of a US reference population), and preterm and SGA combinations. FINDINGS: Pooled overall RRs for preterm were 6·82 (95% CI 3·56-13·07) for neonatal mortality and 2·50 (1·48-4·22) for post-neonatal mortality. Pooled RRs for babies who were SGA (with birthweight in the lowest tenth percentile of the reference population) were 1·83 (95% CI 1·34-2·50) for neonatal mortality and 1·90 (1·32-2·73) for post-neonatal mortality. The neonatal mortality risk of babies who were both preterm and SGA was higher than that of babies with either characteristic alone (15·42; 9·11-26·12). INTERPRETATION: Many babies in low-income and middle-income countries are SGA. Preterm birth affects a smaller number of neonates than does SGA, but is associated with a higher mortality risk. The mortality risks associated with both characteristics extend beyond the neonatal period. Differentiation of the burden and risk of babies born preterm and SGA rather than with low birthweight could guide prevention and management strategies to speed progress towards Millennium Development Goal 4--the reduction of child mortality. FUNDING: Bill & Melinda Gates Foundation