Resurgence and 1/N Expansion in Integrable Field Theories

In theories with renormalons the perturbative series is factorially divergent even after restricting to a given order in 1/N, making the 1/N expansion a natural testing ground for the theory of resurgence. We study in detail the interplay between resurgent properties and the 1/N expansion in various integrable field theories with renormalons. We focus on the free energy in the presence of a chemical potential coupled to a conserved charge, which can be computed exactly with the thermodynamic Bethe ansatz (TBA). In some examples, like the first 1/N correction to the free energy in the non-linear sigma model, the terms in the 1/N expansion can be fully decoded in terms of a resurgent trans-series in the coupling constant. In the principal chiral field we find a new, explicit solution for the large N free energy which can be written as the median resummation of a trans-series with infinitely many, analytically computable IR renormalon corrections. However, in other examples, like the Gross-Neveu model, each term in the 1/N expansion includes non-perturbative corrections which can not be predicted by a resurgent analysis of the corresponding perturbative series. We also study the properties of the series in 1/N. In the Gross-Neveu model, where this is convergent, we analytically continue the series beyond its radius of convergence and show how the continuation matches with known dualities with sine-Gordon theories

Cation-Responsive and Photocleavable Hydrogels from Noncanonical Amphiphilic DNA Nanostructures.

Funder: Imperial College LondonThanks to its biocompatibility, versatility, and programmable interactions, DNA has been proposed as a building block for functional, stimuli-responsive frameworks with applications in biosensing, tissue engineering, and drug delivery. Of particular importance for in vivo applications is the possibility of making such nanomaterials responsive to physiological stimuli. Here, we demonstrate how combining noncanonical DNA G-quadruplex (G4) structures with amphiphilic DNA constructs yields nanostructures, which we termed "Quad-Stars", capable of assembling into responsive hydrogel particles via a straightforward, enzyme-free, one-pot reaction. The embedded G4 structures allow one to trigger and control the assembly/disassembly in a reversible fashion by adding or removing K+ ions. Furthermore, the hydrogel aggregates can be photo-disassembled upon near-UV irradiation in the presence of a porphyrin photosensitizer. The combined reversibility of assembly, responsiveness, and cargo-loading capabilities of the hydrophobic moieties make Quad-Stars a promising candidate for biosensors and responsive drug delivery carriers

Cortical plasticity assessment predicts decline in patients with mild cognitive impairment

AbstractBackgroundAlzheimer`s disease (AD) is characterized by loss of synaptic connections, cell death and disruption of structural and functional networks. One of the most consistent findings is the impairment of cortical plasticity, especially Long Term Potentiation (LTP) mechanisms. Recently, the use of new diagnostic criteria allowed to considered AD as a clinico‐biological entity identifiable in vivo on the presence of biomarkers. In light of these new criteria, aim of the current work is to investigate cortical plasticity in patients with hippocampal type memory impairment admitted for the first time in the memory clinic and stratified according to CSF biomarkers profile; moreover we followed patients up to a period of three years to explore the relationship between neurophysiological, neuropsychological and CSF biomarkers and clinical progression.MethodSeventy‐three patients were recruited and followed up for 36 months. They underwent CSF sampling and Transcranial Magnetic Stimulation to investigate LTP and intracortical circuits. According to the new AD criteria we divided patients in three groups: 1) Mild Cognitive Impaired (MCI) patients (n=21); Prodromal AD (PROAD) patients (n=24); AD Dementia (ADD) patients (n=28).ResultIn neurophysiological evaluations only iTBS protocol was different among the different groups showing a paradoxical reversal of LTP for ADD and PROAD and a poor response for MCI patients. ProAD worsened faster than MCI. Regression analyses showed that LTP impairment was related to clinical progression. Kaplan‐Meyer analyses showed that patients expressing the worst LTP values were the ones to progress faster in a 3 year time.ConclusionThe new criteria based on the presence of biomarkers and dementia allow us to identify patients at a prodromal stage that will develop dementia due to AD. LTP impairment drives the clinical progression in patients at prodromal stages confirming its pivotal role in determining cognitive decline. These results pave the way for the identification of new therapeutic targets such as synaptic plasticity modulators

Informed classification of sweeteners/bitterants compounds via explainable machine learning

Perception of taste is an emergent phenomenon arising from complex molecular interactions between chemical compounds and specific taste receptors. Among all the taste perceptions, the dichotomy of sweet and bitter tastes has been the subject of several machine learning studies for classification purposes. While previous studies have provided accurate sweeteners/bitterants classifiers, there is ample scope to enhance these models by enriching the understanding of the molecular basis of bitter-sweet tastes. Towards these goals, our study focuses on the development and testing of several machine learning strategies coupled with the novel SHapley Additive exPlanations (SHAP) for a rational sweetness/bitterness classification. This allows the identification of the chemical descriptors of interest by allowing a more informed approach toward the rational design and screening of sweeteners/bitterants. To support future research in this field, we make all datasets and machine learning models publicly available and present an easy-to-use code for bitter-sweet taste prediction

Use of Miltefosine in a Patient With Mucosal Leishmaniasis and HIV-coinfection: A Challenge in Long-Term Management

The management of mucosal leishmaniasis in immunocompromised patients is not standardized and limited data are available on the use of miltefosine for treatment and secondary prophylaxis. We describe a case of mucosal leishmaniasis in an HIV-coinfected patient treated with miltefosine due to a severe allergic reaction to liposomal amphotericin B

Predictability and empirical dynamics of fisheries time series in the North Pacific

Previous studies have documented a strong relationship between marine ecosystems and large-scale modes of sea surface height (SSH) and sea surface temperature (SST) variability in the North Pacific such as the Pacific Decadal Oscillation and the North Pacific Gyre Oscillation. In the central and western North Pacific along the Kuroshio-Oyashio Extension (KOE), the expression of these modes in SSH and SST is linked to the propagation of long oceanic Rossby waves, which extend the predictability of the climate system to ~3 years. Using a multivariate physical-biological linear inverse model (LIM) we explore the extent to which this physical predictability leads to multi-year prediction of dominant fishery indicators inferred from three datasets (i.e., estimated biomasses, landings, and catches). We find that despite the strong autocorrelation in the fish indicators, the LIM adds dynamical forecast skill beyond persistence up to 5-6 years. By performing a sensitivity analysis of the LIM forecast model, we find that two main factors are essential for extending the dynamical predictability of the fishery indicators beyond persistence. The first is the interaction of the fishery indicators with the SST/SSH of the North and tropical Pacific. The second is the empirical relationship among the fisheries time series. This latter component reflects stock-stock interactions as well as common technological and human socioeconomic factors that may influence multiple fisheries and are captured in the training of the LIM. These results suggest that empirical dynamical models and machine learning algorithms, such as the LIM, provide an alternative and promising approach for forecasting key ecological indicators beyond the skill of persistence. &nbsp;</p

Tracking Down of a Selected Panel of Parabens: A Validated Method to Evaluate Their Occurrence in Skin Layers

A method was set up and validated to identify and quantify seven parabens in each of the three skin layers, i.e., Stratum Corneum, Epidermis, and Dermis, because, even if only some analogues are legally allowed in Europe, forbidden parabens are also detected in many personal care products and therefore can be absorbed by the skin. A solid/liquid extraction followed by a gradient elution chromatographic separation method was performed and validated according to European guidelines. Our validated method afforded the detection of all seven parabens with limit of detection values ranging from 0.026 to 0.090 μg mL−1 and recoveries ranging from 61.80 to 105.73 μg mL−1 at high and low concentration values (50.0–5.0 μg mL−1), respectively. The proposed method can help assess paraben’s skin bioaccumulation since people are repeatedly exposed to consumer goods containing parabens in their daily routine, posing a chronic risk to human health

A convenient preparation of La2CuO4 from molecular precursors

Exhaustive hydrolysis of a mixture of [La4(CO3)(O2CNBu2)10] and [Cu(O2CNBu2)(py∗)2] (py∗ = 4-dimethylamino pyridine) in molar ratio 1/2 corresponding to a La/Cu molar ratio 2/1 was carried out in toluene at room temperature. The carbamato derivatives of lanthanum and copper can be easily prepared by extraction of the metal ions from aqueous solution into heptane by the NHBu2/CO2 system, according to a method previously reported. The copper precursor was selected among a number of derivatives in respect of its easy tractability. The tetragonal modification T’ of La2CuO4 was obtained by treatment at 600 °C of the intermediate mixed carbonate. The thermal treatment of T’-La2CuO4 at 850 °C, followed by cooling down to room temperature, afforded the orthorhombic modification of the mixed oxide