Multifractality in spin glasses.

We unveil the multifractal behavior of Ising spin glasses in their low-temperature phase. Using the Janus II custom-built supercomputer, the spin-glass correlation function is studied locally. Dramatic fluctuations are found when pairs of sites at the same distance are compared. The scaling of these fluctuations, as the spin-glass coherence length grows with time, is characterized through the computation of the singularity spectrum and its corresponding Legendre transform. A comparatively small number of site pairs controls the average correlation that governs the response to a magnetic field. We explain how this scenario of dramatic fluctuations (at length scales smaller than the coherence length) can be reconciled with the smooth, self-averaging behavior that has long been considered to describe spin-glass dynamics.

Lateral-type posterior fossa ependymomas in pediatric patients: a national collaborative study.

PURPOSE: To review a multicentric series of lateral-type posterior fossa ependymomas operated in the last ten years and to analyze the factors related to clinical evolution and tumor survival. METHODS: Descriptive, retrospective study. Active members of the Spanish Society of Pediatric Neurosurgery were invited to participate in this multicentric study. Clinical and radiological data were incorporated to an open database. The role of histologic grade, grade of resection, postoperative morbidities, and clinical follow-up was evaluated through bivariate associations (chi-square), Kaplan-Meier's curves (log-rank test), and multivariate analysis (binary logistic regression). RESULTS: Fourteen centers entered the study, and 25 cases with a minimum follow-up of 6 months were included. There were 13 boys and 12 girls with a mean age close to 3 years. Mean tumor volume at diagnosis was over 60 cc. A complete resection was achieved in 8 patients and a near-total resection in 5 cases. Fifteen tumors were diagnosed as ependymoma grade 2 and ten as ependymoma grade 3. Major morbidity occurred postoperatively in 14 patients but was resolved in twelve within 6 months. There were six cases of death and 11 cases of tumor progression along the observation period. Mean follow-up was 44.8 months. Major morbidity was significantly associated with histologic grade but not with the degree of resection. Overall and progression-free survival were significantly associated with complete surgical resection. At the last follow-up, 16 patients carried a normal life, and three displayed a mild restriction according to Lansky's scale. CONCLUSIONS: Lateral-type posterior fossa ependymomas constitute a specific pathologic and clinical tumor subtype with bad prognosis. Gross total resection is the goal of surgical treatment, for it significantly improves prognosis with no additional morbidity. Neurological deficits associated to lower cranial nerve dysfunction are common, but most are transient. Deeper genetic characterization of these tumors may identify risk factors that guide new treatments and stratification of adjuvant therapies.

Postural tremor and sexual chromosome aneuploidies: case report and review of literature.

PURPOSE: To examine the link between tremor and sex chromosome abnormalities, emphasizing the necessity of comprehensive physical examination. CASE DESCRIPTION: An 18-year-old man exhibited an isolated action tremor in both hands. Despite having no familial history of tremors and no identifiable secondary causes, his tall stature and learning difficulties suggested a genetic origin. His karyotype confirmed the diagnosis of Jacob's syndrome (XYY syndrome). Therapies with primidone and propranolol were ineffective for his tremor. CONCLUSIONS: Tremor can be caused by various conditions, and aneuploidies might often be overlooked as a cause. They should be considered in young patients with concrete phenotypes and negative familiar history of tremors. Karyotyping is a cost-effective diagnostic tool crucial for genetic counselling. Common treatments for tremors often yield unsatisfactory results in these cases.

Anticoagulation improves survival in patients with cirrhosis and portal vein thrombosis: The IMPORTAL competing-risk meta-analysis.

BACKGROUND & AIMS: Previous meta-analyses demonstrated the safety and efficacy of anticoagulation in the recanalization of portal vein thrombosis in patients with cirrhosis. Whether this benefit translates into improved survival is unknown. We conducted an individual patient data (IPD) meta-analysis to assess the effect of anticoagulation on all-cause mortality in patients with cirrhosis and portal vein thrombosis. METHODS: In this IPD meta-analysis, we selected studies comparing anticoagulation vs. no treatment in patients with cirrhosis and portal vein thrombosis from PubMed, Embase, and Cochrane databases (until June 2020) (PROSPERO no.: CRD42020140026). IPD were subsequently requested from authors. The primary outcome - the effect of anticoagulation on all-cause mortality - was assessed by a one-step meta-analysis based on a competing-risk model with liver transplantation as the competing event. The model was adjusted for clinically relevant confounders. A multilevel mixed-effects logistic regression model was used to determine the effect of anticoagulation on recanalization. RESULTS: Individual data on 500 patients from five studies were included; 205 (41%) received anticoagulation and 295 did not. Anticoagulation reduced all-cause mortality (adjusted subdistribution hazard ratio 0.59; 95% CI 0.49-0.70), independently of thrombosis severity and recanalization. The effect of anticoagulation on all-cause mortality was consistent with a reduction in liver-related mortality. The recanalization rate was higher in the anticoagulation arm (adjusted odds ratio 3.45; 95% CI 2.22-5.36). The non-portal-hypertension-related bleeding rate was significantly greater in the anticoagulation group. CONCLUSIONS: Anticoagulation reduces all-cause mortality in patients with cirrhosis and portal vein thrombosis independently of recanalization, but at the expense of increasing non-portal hypertension-related bleeding. PROSPERO REGISTRATION NUMBER: CRD42020140026. IMPACT AND IMPLICATIONS: Anticoagulation is effective in promoting recanalization of portal vein thrombosis in patients with cirrhosis, but whether this benefit translates into improved survival is controversial. Our individual patient data meta-analysis based on a competing-risk model with liver transplantation as the competing event shows that anticoagulation reduces all-cause mortality in patients with cirrhosis and portal vein thrombosis independently of recanalization. According to our findings, portal vein thrombosis may identify a group of patients with cirrhosis that benefit from long-term anticoagulation.

Accelerated Polyethylene Terephthalate (PET) Enzymatic Degradation by Room Temperature Alkali Pre-treatment for Reduced Polymer Crystallinity.

Polyethylene terephthalate (PET) is the most widely employed plastic for single-use applications. The use of enzymes isolated from microorganisms, such as PETase with the capacity to hydrolyze PET into its monomers, represents a promising method for its sustainable recycling. However, the accessibility of the enzyme to the hydrolysable bonds is an important challenge that needs to be addressed for effective biodegradation of postconsumer PET. Here, we combined an alkali pre-treatment (25 °C) with PETase incubation (30 °C) with post-consumed PET bottles. The pre-treatment modifies the surface of the plastic and decreases its crystallinity enabling the access of the enzyme to the hydrolysable chemical bonds. When the alkali pre-treatment is incorporated into the enzymatic process the degradation yields increase more than one order of magnitude reaching values comparable to those obtained during heating/cooling cycles. Our results show energetic advantages over other reported pre-treatments and open new avenues for sustainable PET recycling.

Impedance Spectroscopy of Metal Halide Perovskite Solar Cells from the Perspective of Equivalent Circuits.

Impedance spectroscopy (IS) provides a detailed understanding of the dynamic phenomena underlying the operation of photovoltaic and optoelectronic devices. Here we provide a broad summary of the application of IS to metal halide perovskite materials, solar cells, electrooptic and memory devices. IS has been widely used to characterize perovskite solar cells, but the variability of samples and the presence of coupled ionic-electronic effects form a complex problem that has not been fully solved yet. We summarize the understanding that has been obtained so far, the basic methods and models, as well as the challenging points still present in this research field. Our approach emphasizes the importance of the equivalent circuit for monitoring the parameters that describe the response and providing a physical interpretation. We discuss the possibilities of models from the general perspective of solar cell behavior, and we describe the specific aspects and properties of the metal halide perovskites. We analyze the impact of the ionic effects and the memory effects, and we describe the combination of light-modulated techniques such as intensity modulated photocurrent spectroscopy (IMPS) for obtaining more detailed information in complex cases. The transformation of the frequency to time domain is discussed for the consistent interpretation of time transient techniques and the prediction of features of current-voltage hysteresis. We discuss in detail the stability issues and the occurrence of transformations of the sample coupled to the measurements.

Personal exposimeter coupled to a drone as a system for measuring environmental electromagnetic fields.

Personal exposimeters are currently used in studies assessing human exposure to electromagnetic fields. These devices are usually carried by an individual, but vehicles such as bicycle or car are also used. The aim of the present study was to propose a personal exposimeter attached to a drone to perform environmental radio-frequency measurements. Trials were carried out to determine whether: (i) the wireless communication between the remote controller and the drone affects the downlink mobile telephony bands by a cross-talk effect, and (ii) the structure of the drone alters the measurements of the exposimeter compared to when the meter is on a tripod. To apply this system to a real scenario, a 3D representation of the electric field in a building was obtained, and the attenuation due to the building of radiation from outside was estimated. Measurements of the electromagnetic field with this system will make it possible to monitor without risk the emissions of antennas in their close vicinity, and to validate propagation models experimentally.

Retrospective and Prospective Analysis on "Sexting": Indicators of Productivity, Dispersion, and Content (2009-2019).

In the last decade, research on "sexting" has undergone an exponential increase, giving rise to the publication of numerous studies clarifying its meaning, offering information of educational value, and favoring a good use of technology to prevent problems caused by this exchange of sexual information. The aim of this article was to analyze the production, performance, impact, and content of scientific articles evaluating the "sexting" thesaurus (title, abstract, and/or keywords) between 2009 and September 2019. Articles were sourced from two internationally recognized databases: Scopus and Web of Science. A scientometric study was then carried out on a sample of 641 articles that met the established inclusion criteria. The main findings indicate that "sexting" is a very recent research focus, but one in full growth phase, with scientific production related to the topic likely to double over the next few years. Although "sexting" has been researched worldwide, the scientific production of the US and American authors is the most notable. There were also some differences between the Scopus and Web of Science databases, mainly in the volume of production and the trend. However, the studies do show a common research line, "cyberbullying," and a common target population: adolescents. Therefore, the content analysis reveals that research on "sexting" is mostly carried out with adolescents and takes into consideration other themes such as cyberbullying, dating violence, and sexuality.

Comparative Study of Machine Learning Models for Bee Colony Acoustic Pattern Classification on Low Computational Resources.

In precision beekeeping, the automatic recognition of colony states to assess the health status of bee colonies with dedicated hardware is an important challenge for researchers, and the use of machine learning (ML) models to predict acoustic patterns has increased attention. In this work, five classification ML algorithms were compared to find a model with the best performance and the lowest computational cost for identifying colony states by analyzing acoustic patterns. Several metrics were computed to evaluate the performance of the models, and the code execution time was measured (in the training and testing process) as a CPU usage measure. Furthermore, a simple and efficient methodology for dataset prepossessing is presented; this allows the possibility to train and test the models in very short times on limited resources hardware, such as the Raspberry Pi computer, moreover, achieving a high classification performance (above 95%) in all the ML models. The aim is to reduce power consumption and improves the battery life on a monitor system for automatic recognition of bee colony states.

Treatment of portal vein thrombosis in cirrhosis patients.

Portal vein thrombosis is an uncommon complication in patients with cirrhosis, typically manifesting in the advanced stages of the disease. Although robust evidence is lacking, anticoagulation is indicated in specific patient subgroups, either those with severe portal occlusion or those requiring attempted portal recanalization due to their unique transplant situation. Beyond recanalization, anticoagulation appears to exert a beneficial effect on the natural history of cirrhosis, which raises uncertainties about the appropriateness of discontinuing it once initiated.

Chemical Inductor.

A multitude of chemical, biological, and material systems present an inductive behavior that is not electromagnetic in origin. Here, it is termed a chemical inductor. We show that the structure of the chemical inductor consists of a two-dimensional system that couples a fast conduction mode and a slowing down element. Therefore, it is generally defined in dynamical terms rather than by a specific physicochemical mechanism. The chemical inductor produces many familiar features in electrochemical reactions, including catalytic, electrodeposition, and corrosion reactions in batteries and fuel cells, and in solid-state semiconductor devices such as solar cells, organic light-emitting diodes, and memristors. It generates the widespread phenomenon of negative capacitance, it causes negative spikes in voltage transient measurements, and it creates inverted hysteresis effects in current-voltage curves and cyclic voltammetry. Furthermore, it determines stability, bifurcations, and chaotic properties associated to self-sustained oscillations in biological neurons and electrochemical systems. As these properties emerge in different types of measurement techniques such as impedance spectroscopy and time-transient decays, the chemical inductor becomes a useful framework for the interpretation of the electrical, optoelectronic, and electrochemical responses in a wide variety of systems. In the paper, we describe the general dynamical structure of the chemical inductor and we comment on a broad range of examples from different research areas.

The Mpemba effect in spin glasses is a persistent memory effect.

The Mpemba effect occurs when a hot system cools faster than an initially colder one, when both are refrigerated in the same thermal reservoir. Using the custom-built supercomputer Janus II, we study the Mpemba effect in spin glasses and show that it is a nonequilibrium process, governed by the coherence length ξ of the system. The effect occurs when the bath temperature lies in the glassy phase, but it is not necessary for the thermal protocol to cross the critical temperature. In fact, the Mpemba effect follows from a strong relationship between the internal energy and ξ that turns out to be a sure-tell sign of being in the glassy phase. Thus, the Mpemba effect presents itself as an intriguing avenue for the experimental study of the coherence length in supercooled liquids and other glass formers.

Marine Collagen-Based Antibacterial Film Reinforced with Graphene and Iron Oxide Nanoparticles.

It has become more widely available to use biopolymer-based films as alternatives to conventional plastic-based films due to their non-toxic properties, flexibility, and affordability. However, they are limited in application due to deficiencies in their properties. The marine collagen was the specimen for the present study. Thus, the main objective was to reinforce marine collagen-based films with 1.0% (w/w of the dry polymer weight) of iron oxide nanoparticles (IO-NPs), graphene oxide nanoparticles (GO-NPs), or a combination of both oxides (GO-NPs/IO-NPs) as antibacterial and antioxidant additives to overcome some of the limitations of the film. In this way, the nanoparticles were incorporated into the film-forming solution (2% w/v in acetic acid, 0.05 M) and processed by casting. Thereafter, the films were dried and analyzed for their physicochemical, mechanical, microstructural, and functional properties. The results show that the effective combination of GO-NPs/IO-NPs enhanced the physicochemical properties by increasing the water contact angle (WCA) of the films from 77.2 to 84.4° and their transparency (T) from 0.5 to 5.2. Furthermore, these nanoparticles added antioxidant and antibacterial value to the films, with free radical inhibition of up to 95.8% and 23.8 mm of bacteria growth inhibition (diameter). As a result, both types of nanoparticles are proposed as suitable additives to be incorporated into films and enhance their different properties.

Update on the diagnosis and management of portal hypertension in cirrhosis according to the Baveno VII Consensus Conference recommendations.

Development of portal hypertension is the most critical hallmark in the natural history of advanced chronic liver disease, as it is responsible for most liver decompensations. Correct risk stratification allows the design of personalized treatment strategies. In addition, the dynamic nature of chronic liver disease requires a refinement of both invasive and non-invasive diagnostic methods at every stage. Treatment with non-selective beta blockers and suppression of the etiologic factor improve portal hypertension and decrease the probability of decompensation in high-risk patients. Patients admitted for variceal hemorrhage also benefit from personalized management, where insertion of a preventive TIPS plays a relevant role.

First patient with mosaic NOTCH3 gene pathogenic variant. Unrevealed mosaicisms and importance of their detection.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an inherited small vessel disease caused predominantly by pathogenic variants in NOTCH3 gene. Neither germline nor somatic mosaicism has been previously published in NOTCH3 gene. CADASIL is inherited in an autosomal dominant manner; only rare cases have been associated with de novo pathogenic variants. Mosaicism is more common than previously thought because mosaic variants often stay unrevealed. An apparently de novo variant might actually be a consequence of a parental mosaicism undetectable with Sanger sequencing, especially in the case of low grade mosaicism. Parental testing by sensitive tools like deep targeted next-generation sequencing (NGS) analysis could detect cases of unrevealed medium or low level mosaicism in patients tested by Sanger sequencing. Here, we report the first patient with mosaic NOTCH3 gene pathogenic variant to our knowledge; the allelic fraction in the leucocyte DNA was low (13%); the pathogenic variant was inhered by his two daughters. The patient was diagnosed by deep targeted NGS analysis after studying his two affected daughters. This report highlights the importance of parental testing by sensitive tools like deep targeted NGS analysis. Detection of mosaicism is of great importance for diagnosis and adequate family genetic counseling.

Hepatocellular carcinoma risk in hepatitis C stage-3 fibrosis after sustained virological response with direct-acting antivirals.

BACKGROUND & AIMS: Patients with chronic hepatitis C and stage 3 fibrosis are thought to remain at risk of hepatocellular carcinoma after sustained virological response. We investigated this risk in a large cohort of patients with well-defined stage 3 fibrosis. METHODS: We performed a multicentre, ambispective, observational study of chronic hepatitis C patients with sustained virological response after treatment with direct-acting antivirals started between January and December 2015. Baseline stage 3 was defined in a two-step procedure: we selected patients with transient elastography values of 9.5-14.5 kPa and subsequently excluded those with nodular liver surface, splenomegaly, ascites or collaterals on imaging, thrombopenia or esophago-gastric varices. Patients were screened twice-yearly using ultrasound. RESULTS: The final sample comprised 506 patients (median age, 57.4 years; males, 59.9%; diabetes, 17.2%; overweight, 44.1%; genotype 3, 8.9%; HIV coinfection, 18.4%; altered liver values, 15.2%). Median follow-up was 33.7 (22.1-39.1) months. Five hepatocellular carcinomas and 1 cholangiocarcinoma were detected after a median of 29.4 months (95% CI: 26.8-39.3), with an incidence of 0.47/100 patients/year (95% CI: 0.17-1.01). In the multivariate analysis, only males older than 55 years had a significant higher risk (hazard ratio 7.2 [95% CI: 1.2-41.7; P = .029]) with an incidence of 1.1/100 patients/year (95% CI: 0.3-2.8). CONCLUSIONS: In a large, well-defined cohort of patients with baseline hepatitis C stage-3 fibrosis, the incidence of primary liver tumours was low after sustained virological response and far from the threshold for cost-effectiveness of screening, except in males older than 55 years.

Hepatocellular carcinoma after Fontan surgery: A systematic review.

AIM: Fontan surgery is often the procedure of choice for patients with congenital single effective ventricle. In the long term, elevated systemic venous pressure and chronic ischemia following this procedure could lead to advanced chronic liver disease and there is also a risk of hepatocellular carcinoma (HCC). This review systematically summarizes the characteristics and outcomes of this rare condition. METHODS: PubMed and Embase databases were searched from inception to January 2020 for studies reporting on HCC after Fontan surgery. The factors analyzed were clinical presentation, histology, imaging findings, treatments, and survival. Our primary analysis was based on biopsy-proven HCC. RESULTS: The records selected were 26 observational studies (19 case reports/case series and seven cohort studies) including 65 biopsy-proven HCC. Age at the time of HCC diagnosis ranged from 12 to 52 years, and 62% of the patients were female. Only one case occurred earlier than 10 years after Fontan surgery. Twenty patients had no imaging or histological evidence of liver cirrhosis and 78.3% had elevated α-fetoprotein levels. Advanced stage was the most common at diagnosis. The most frequent treatments were transarterial chemoembolization (n = 18) and surgery (n = 12). One-year survival was 50% and only four patients (6.2%) were under liver imaging surveillance. We also analyzed 17 patients with non-biopsy-proven HCC. CONCLUSIONS: After Fontan surgery, HCC usually occurs at least 10 years later and can develop in the absence of cirrhosis. Biopsy is mandatory to confirm the diagnosis. Patients were diagnosed at a late stage and survival outcomes were poor, highlighting a need for liver surveillance.

Flow ventricular catheters for shunted hydrocephalus: initial clinical results.

BACKGROUND: The non-homogenous flow of the cerebrospinal fluid within the ventricular catheter is one of the causative factors in shunt obstructions during the treatment of hydrocephalus. Previously, we studied the flow in ventricular catheters under the steady and pulsatile boundary conditions by means of computational fluid dynamics (CFD) in three-dimensional paradigms. Subsequently, several catheter designs with homogeneous flow patterns were developed out of which one prototype was chosen after a validation study. OBJECTIVE: To test the effectiveness of the flow ventricular catheter in a prospective, multicenter, comparative study. METHODS: Eligible centers were three pediatric hospitals: two with sole adult practice and one a mixed pediatric-adult. Standard silicone material was used to develop a parametric catheter model with homogenous flow characteristics. The flow catheters were inserted in pediatric (n = 30) and adult (n = 10) patients with all types of hydrocephalus. Simultaneously, regular ventricular catheters were inserted in another 43 control patients in the participating centers. Catheter positioning was standardized according to the Schaumann and Thomale classification. RESULTS: All ventricular catheters had a cephalad grade I or II positioning, and caudally, its extension had a peritoneal location. Programmable valves were utilized in 70% and antisiphon devices in 20% of the cases. Regular differential pressure valves were utilized in the remaining. No case of flow catheter obstruction was identified during a mean follow-up period of 2 years at the time of this writing. There were four catheter obstructions in the control cohort, all pediatric cases, during the first year. Shunt infections occurred in two cases in the control group, while there was one recurrent case of adult ventriculitis in the flow catheter group. CONCLUSIONS: This prototype model represents the next generation of ventricular catheters with a homogeneous flow pattern. The flow catheter can be inserted safely in hydrocephalic patients, and this preliminary prospective comparative study showed a possible obstruction-free functionality.

Decreased Levels of Thioredoxin o1 Influences Stomatal Development and Aperture but Not Photosynthesis under Non-Stress and Saline Conditions.

Salinity has a negative impact on plant growth, with photosynthesis being downregulated partially due to osmotic effect and enhanced cellular oxidation. Redox signaling contributes to the plant response playing thioredoxins (TRXs) a central role. In this work we explore the potential contribution of Arabidopsis TRXo1 to the photosynthetic response under salinity analyzing Arabidopsis wild-type (WT) and two Attrxo1 mutant lines in their growth under short photoperiod and higher light intensity than previous reported works. Stomatal development and apertures and the antioxidant, hormonal and metabolic acclimation are also analyzed. In control conditions mutant plants displayed less and larger developed stomata and higher pore size which could underlie their higher stomatal conductance, without being affected in other photosynthetic parameters. Under salinity, all genotypes displayed a general decrease in photosynthesis and the oxidative status in the Attrxo1 mutant lines was altered, with higher levels of H2O2 and NO but also higher ascorbate/glutathione (ASC/GSH) redox states than WT plants. Finally, sugar changes and increases in abscisic acid (ABA) and NO may be involved in the observed higher stomatal response of the TRXo1-altered plants. Therefore, the lack of AtTRXo1 affected stomata development and opening and the mutants modulate their antioxidant, metabolic and hormonal responses to optimize their adaptation to salinity.

Health-related quality of life in nonvalvular atrial fibrillation patients with controlled or uncontrolled anticoagulation status.

BACKGROUND: There is a dearth of evidence regarding Health-Related Quality of Life (HRQoL) in nonvalvular atrial fibrillation (NVAF) patients undergoing oral anticoagulation therapy. Our objective was to describe HRQoL in NVAF patients on oral anticoagulation, focusing on uncontrolled patients on vitamin K antagonists (VKAs) versus controlled patients on VKAs or non-vitamin K antagonist oral anticoagulants (NOACs), in a real-world setting. Additionally, we assessed the clinical characteristics of patients with uncontrolled anticoagulation. METHODS: An observational, multicentre, and cross-sectional study, enrolling 38 Spanish Hospitals' Internal Medicine Departments. HRQoL was assessed using the validated Spanish version of the Sawicki questionnaire. High self-perceived HRQoL was indicated by high scores in the general treatment satisfaction and self-efficacy dimensions, and by low scores in the strained social network, daily hassles and distress dimensions. RESULTS: Five hundred and one patients were included for assessment. Mean scores ± SD were closer to a high perceived HRQoL in controlled than uncontrolled patients for the five dimensions of the questionnaire: 4.9 ± 1.0 versus 3.6 ± 1.3 for general treatment satisfaction; 4.3 ± 1.0 versus 3.6 ± 1.0 for self-efficacy, 3.1 ± 0.9 versus 3.9 ± 1.1 for strained social network, 2.1 ± 0.8 versus 3.0 ± 1.0 for daily hassles and 1.8 ± 0.9 versus 2.6 ± 1.2 for distress. CONCLUSIONS: HRQoL in patients with controlled anticoagulant status treated with NOACs or VKAs was better than in patients with uncontrolled anticoagulant status. This seems to indicate that anticoagulation control status influences perception of HRQoL, highlighting the importance of its evaluation when assessing HRQoL in NVAF patients.