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In this work, we describe the synthesis of halogenated pyran analogues of ᴅ-talose using a halo-divergent strategy from known 1,6-anhydro-2,3-dideoxy-2,3-difluoro-β-ᴅ-mannopyranose. In solution and in the solid-state, all analogues adopt standard 4C1-like conformations despite 1,3-diaxial repulsion between the F2 and the C4 halogen. Moreover, the solid-state conformational analysis of halogenated pyrans reveals deviation in the intra-annular torsion angles arising from repulsion between the axial fluorine at C2 and the axial halogen at C4, which increases with the size of the halogen at C4 (F < Cl < Br < I). Crystal packing arrangements of pyran inter-halides show hydrogen bond acceptor and nonbonding interactions for the halogen at C4. Finally, density functional theory (DFT) calculations corroborate the preference of talose analogues to adopt a 4C1-like conformation and a natural bonding orbital (NBO) analysis demonstrates the effects of hyperconjugation from C–F antibonding orbitals.

Abstract Applying machine learning to continuous acoustic emissions, signals previously deemed noise, from laboratory faults and slowly slipping subduction‐zone faults, demonstrates hidden signatures are emitted that describe physical details, including fault displacement and friction. However, no evidence currently exists to demonstrate that similar hidden signals occur during seismogenic stick‐slip on earthquake faults—the damaging earthquakes of most societal interest. We show that continuous seismic emissions emitted during the 2018 multi‐month caldera collapse sequence at the Kı̄lauea volcano in Hawai'i contain hidden signatures characterizing the earthquake cycle. Multi‐spectral data features extracted from 30 s intervals of the continuous seismic emission are used to train a gradient boosted tree regression model to predict the GNSS‐derived contemporaneous surface displacement and time‐to‐failure of the upcoming collapse event. This striking result suggests that at least some faults emit such signals and provide a potential path to characterizing the instantaneous and future behavior of earthquake faults.

By teaching machine learning models with earthquake fault numerical simulations laboratory fault slip is predictable. Training the model further with a snippet of laboratory data improves predictions suggesting an approach to probing faults in Earth.

A deep neural network is developed to automatically extract ground deformation from Interferometric Synthetic Aperture Radar time series. Applied to data over the North Anatolian Fault, the method can detect 2 mm deformation transients and reveals a slow earthquake twice as extensive as previously recognized.

The orientation of maximum horizontal compressive stress in the crust can be estimated in regions lacking borehole or earthquake source data through the use of ambient Earth noise to measure stress-induced anisotropy of nonlinear anelastic behavior.

In this work, we have developed a simple synthetic approach using Et3N·3HF as an alternative to the DAST reagent. We controlled the stereochemistry of the nucleophilic fluorination at C4 of 1,6-anhydro-2,3-dideoxy-2,3-difluoro-4-O-triflate-β-ᴅ-talopyranose using Et3N·3HF or in situ generated Et3N·1HF. The influence of the fluorine atom at C2 on reactivity at C4 could contribute to a new fluorine effect in nucleophilic substitution. Finally, with the continuous objective of synthesizing novel multi-vicinal fluorosugars, we prepared one difluorinated and one trifluorinated alditol analogue.

Using machine learning algorithms, the authors here identify slow slip precursors in the Cascadia subduction zone to last for months - which in turn argues for a much better predictability of slow slip rupture.

Abstract Slow earthquakes may trigger failure on neighboring locked faults that are stressed sufficiently to break, and slow slip patterns may evolve before a nearby great earthquake. However, even in the clearest cases such as Cascadia, slow earthquakes and associated tremor have only been observed in intermittent and discrete bursts. By training a convolutional neural network to detect known tremor on a single seismic station in Cascadia, we isolate and identify tremor and slip preceding and following known larger slow events. The deep neural network can be used for the detection of quasi‐continuous tremor, providing a proxy that quantifies the slow slip rate. Furthermore, the model trained in Cascadia recognizes tremor in other subduction zones and also along the San Andreas Fault at Parkfield, suggesting a universality of waveform characteristics and source processes, as posited from experiments and theory.

Polyfluorinated hexopyranoses display unique physical, chemical and biological properties, however their stereoselective synthesis is highly challenging. Here, the authors report a synthetic approach based on the chemical manipulation of inexpensive levoglucosan to obtain heavily fluorinated monosaccharides stereoselectively.

Analyzing transportation network vulnerabilities to disruptions is crucial for society to maintain commodity flows across the globe. However, most vulnerability analyses focus on impacts that arise from the deterioration of single network components, which can overlook spatial correlations between multiple components that manifest during area-spanning disruptions, such as those stemming from natural hazards. Here, we demonstrate an intuitive, simulation-based approach for inferring spatial vulnerabilities to area-spanning disruptions. In particular, we show how partial dependence plots derived from gradient boosting machines trained on the results of a routing simulation can be used to depict the average effect a disruption’s location has on impacts while controlling for other input variables and spatial dependencies embedded in the network. Although we demonstrate our approach for Middle Tennessee’s intermodal road and rail freight transportation network, our framework can easily be applied to other networks.

En contraste con el paisaje mayormente deshidratado de Don Quijote, Los trabajos de Persiles y Sigismunda es lo que podría llamarse una novela “húmeda”. Gran parte de la Historia setentrional tiene lugar en el mar y la acción narrativa depende estrechamente de la incertidumbre de las fortunas marítimas, sea en aguas del Norte o del Mediterráneo. Aunque la comparación entre la navegación y la composición literaria ha sido un lugar común desde la Antigüedad, últimamente los críticos literarios de otras disciplinas se han interesado mucho por lo que se ha acuñado «los estudios oceánicos» o «las humanidades azules». Propongo explorar cómo el mar interviene específicamente en las relaciones afectivas de los personajes del Persiles y cómo las emociones se nutren de su ambiente náutico. El amor, la tristeza, el miedo y la ansiedad están ligados íntimamente a metáforas e imaginería hidráulica o marítima en la novela. Como análogo exotizado del Mediterráneo que tan bien conocía Cervantes, los mares septentrionales le permitieron experimentar con emociones todavía más intensas, que a su vez nos invitan a reflexionar sobre cómo navegar un paisaje o un texto que depende tanto del agua.

Previous studies in rodents have indicated that function and survival of transplanted islets can be substantially improved by mesenchymal stem cells (MSC). The few human islet studies to date have confirmed these findings but have not determined whether physical contact between MSC and islets is required or whether the benefit to islets results from MSC-secreted proteins. This study aimed to investigate the protective capacity of MSC-preconditioned media for human islets. MSC were cultured for 2 or 5 days in normoxia or hypoxia before harvesting the cell-depleted media for human islet culture in normoxia or hypoxia for 6–8 or 3–4 days, respectively. To characterize MSC-preconditioned media, proteomic secretome profiling was performed to identify angiogenesis- and inflammation-related proteins. A protective effect of MSC-preconditioned media on survival and in vitro function of hypoxic human islets was observed irrespective of the atmosphere used for MSC preconditioning. Islet morphology changed markedly when media from hypoxic MSC were used for culture. However, PDX-1 and insulin gene expression did not confirm a change in the genetic phenotype of these islets. Proteomic profiling of preconditioned media revealed the heterogenicity of the secretome comprising angiogenic and antiapoptotic as well as angiostatic or proinflammatory mediators released at an identical pattern regardless whether MSC had been cultured in normoxic or hypoxic atmosphere. These findings do not allow a clear discrimination between normoxia and hypoxia as stimulus for protective MSC capabilities but indicate an ambivalent character of the MSC angiogenesis- and inflammation-related secretome. Nevertheless, culture of human islets in acellular MSC-preconditioned media resulted in improved morphological and functional islet integrity suggesting a disbalance in favor of protective factors. Further approaches should aim to eliminate potentially detrimental factors to enable the production of advanced clinical grade islet culture media with higher protective qualities.

Summary: Glucagon, the principal hyperglycemic hormone, is secreted from pancreatic islet α cells as part of the counter-regulatory response to hypoglycemia. Hence, secretory output from α cells is under high demand in conditions of low glucose supply. Many tissues oxidize fat as an alternate energy substrate. Here, we show that glucagon secretion in low glucose conditions is maintained by fatty acid metabolism in both mouse and human islets, and that inhibiting this metabolic pathway profoundly decreases glucagon output by depolarizing α cell membrane potential and decreasing action potential amplitude. We demonstrate, by using experimental and computational approaches, that this is not mediated by the KATP channel, but instead due to reduced operation of the Na+-K+ pump. These data suggest that counter-regulatory secretion of glucagon is driven by fatty acid metabolism, and that the Na+-K+ pump is an important ATP-dependent regulator of α cell function. : Glucagon is secreted from pancreatic α cells in hypoglycemic conditions. Briant et al. demonstrate that this response is fueled by fatty acid oxidation. The energy generated by oxidation is used to maintain membrane potential dynamics, action potential morphology, and Na+-K+ pump activity. Keywords: islet, metabolism, glucose, Ca2+, KATP, liver, fasting

Agency activated through exchanges with saints is not simply present or absent. Rather it is emergent, depending on the mode of saints’ material and social configurations, and the mood evoked by a specific saint’s manifestation. In this essay I consider the history of an Afro-Brazilian saint called Slave Anastácia, as she signifies with varying social effects for different groups of ethno-racial users. I consider how saints become manifest in a given mode, and educe a particular mood. Mood is inseparable from intangible entities’ “presence.” In this essay, I leverage such radical disjunctures between the forms of presence generated by the same saint—Anastácia as suffering martyr, as serene helpmeet, as erotic object—to reconsider how saints work at the intersection of mode and mood. By paying attention to saints and mood, I seek to worry over-familiar terms like will and agency. Thinking through mood points us toward material conjunctures and emotional resonances whose agency is diffuse but nevertheless generates predispositions to act in certain ways.

Dodecacius Schwarz is reviewed, it includes two species known only from the eastern lower slopes of the Andes and adjacent Amazonia in southeastern Peru. Dodecacius paititi new species is described. Dodecacius testaceus Schwarz is treated as a new synonym of D. nigricollis Schwarz.

Background Stroke survivors have high rates of mortality and recurrent stroke. Stroke patients are often unable to participate in decision making, highlighting the need for advance care planning (ACP) in poststroke care. We sought to better understand experiences and perceptions around stroke risk and ACP in our stroke clinic. Methods and Results Clinic patients completed the Planning After Stroke Survival survey assessing (1) advance directive (AD) documentation and ACP conversations, (2) factors associated with ADs and ACP, (3) perceptions of stroke risk, and (4) ACP needs. We used a physician survey and the electronic medical record to assess clinical and demographic information. We collected 219 surveys (78% response rate). Forty‐five percent reported having completed ADs, although the correlation between patient report and EMS documentation of ADs was low. Most patients (73%) had discussed ACP, and 58% desired additional conversation. Predictors of completing ADs included age (≥65 years; odds ratio, 4.8; 95% CI, 2.3–10.1), white race (odds ratio, 3.1; 95% CI, 1.2–7.8), milder poststroke disability (modified Rankin Scale score ≤1; odds ratio, 2.9; 95% CI, 1.3–6.4), having previously discussed ACP with a physician (odds ratio, 4.8; 95% CI, 2.0–11.7), and discussing risk of stroke recurrence (odds ratio, 2.2; 95% CI, 1.1–4.5). Conclusions Stroke survivors had low AD completion rates and desired more conversations about stroke risk and ACP. Completed ADs were inconsistently documented in the electronic medical record. These findings provide guidance to improve ACP in our stroke clinic and may provide a model for others interested in enhancing ACP and ultimately goal‐concordant care.