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The precipitation of struvite, a magnesium ammonium phosphate hexahydrate (MgNH4PO4 · 6H2O) mineral, from wastewater is a promising method for recovering phosphorous. While this process is commonly used in engineered environments, our understanding of the underlying mechanisms responsible for the formation of struvite crystals remains limited. Specifically, indirect evidence suggests the involvement of an amorphous precursor and the occurrence of multi-step processes in struvite formation, which would indicate non-classical paths of nucleation and crystallization. In this study, we use synchrotron-based in situ x-ray scattering complemented by cryogenic transmission electron microscopy to obtain new insights from the earliest stages of struvite formation. The holistic scattering data captured the structure of an entire assembly in a time-resolved manner. The structural features comprise the aqueous medium, the growing struvite crystals, and any potential heterogeneities or complex entities. By analysing the scattering data, we found that the onset of crystallization causes a perturbation in the structure of the surrounding aqueous medium. This perturbation is characterized by the occurrence and evolution of Ornstein-Zernike fluctuations on a scale of about 1 nm, suggesting a non-classical nature of the system. We interpret this phenomenon as a liquid-liquid phase separation, which gives rise to the formation of the amorphous precursor phase preceding actual crystal growth of struvite. Our microscopy results confirm that the formation of Mg-struvite includes a short-lived amorphous phase, lasting >10 s. [ABSTRACT FROM AUTHOR]

Let G be a Beauville p-group. If G exhibits a 'good behaviour' with respect to taking powers, then every lift of a Beauville structure of G / Φ (G) is a Beauville structure of G. We say that G is a Beauville p-group of wild type if this lifting property fails to hold. Our goal in this paper is twofold: firstly, we fully determine the Beauville groups within two large families of p-groups of maximal class, namely metabelian groups and groups with a maximal subgroup of class at most 2; secondly, as a consequence of the previous result, we obtain infinitely many Beauville p-groups of wild type. [ABSTRACT FROM AUTHOR]

We prove the equivalence between integral and local central limit theorem for spin system interacting via an absolutely summable pair potential without any conditions on the temperature of the system. [ABSTRACT FROM AUTHOR]

We discuss a model describing the spin orbit resonance cascade. We assume that the body has a two-layer (core–shell) structure; it is composed of a thin external shell and an inner and heavier solid core that are interacting due to the presence of a viscous friction. We assume two sources of dissipation: a viscous one, depending on the relative angular velocity between core and shell and a tidal one, smaller than the first, due to the viscoelastic structure of the core. We show how these two sources of dissipation are needed for the capture in spin–orbit resonance. The shell and the core fall in resonance with different time scales if the viscous coupling between them is big enough. Finally, the tidal dissipation of the viscoelastic core, decreasing the eccentricity, brings the system out of the resonance in a third very long time scale. This mechanism of entry and exit from resonance ends in the 1 : 1 stable state. [ABSTRACT FROM AUTHOR]

Drying shrinkage during ambient pressure drying of silica gels is made reversible by preventing condensation reactions of surface silanol groups via surface modification. This partial recovery of the gel volume and structure is referred to as the spring-back effect (SBE) and enables the production of monolithic silica aerogels by evaporative drying. The SBE is sometimes completed by annealing at mild temperatures. Similarities between drying-related deformations and deformations induced by mechanical stimuli suggest analogous underlying mechanisms. While the causes of drying shrinkage are relatively well-known, it remains unclear how the relaxation of the structure by drying and annealing occurs across the different length scales. Here we show a complete structural recovery of silica aerogels at the macro- and nano-scale enabled by annealing. We propose that residual deformations after drying and mechanical compression are caused by the entanglement of silica clusters that can be unraveled by annealing at 230 °C. The deformation under loading is interpreted as two different re-arrangement mechanisms for dry and annealed gels, by the sliding of the silica clusters along the loading direction and by the compression of large pores beyond the fractal structure, respectively. Our results demonstrate how the shape and structure of silica aerogels can be restored and controlled by thermal activation, broadening the various applications of these materials. We also emphasize how tuning silica gels to promote a two-step SBE by annealing can pave the way toward the production of larger monolithic aerogels by APD. Highlights: Two-step spring-back of silica aerogels upon annealing at 230 °C. Residual solvent and silica cluster entanglement hinder full re-expansion. Annealed aerogels show a near-zero Poisson's ratio during compression. Interpretation of fractal dimension evolution during deformation of mesoporous materials. Annealing allows full recovery of macro- and nano-structure, highlighting programmable nature. [ABSTRACT FROM AUTHOR]

Modern Regional Trade Agreements (RTAs) include, among other chapters, ones concerning sanitary and phytosanitary (SPS) measures and technical barriers to trade (TBT). Drawing on recent literature highlighting the relationship between "deep" RTAs and the global organisation of production, this paper empirically investigates whether these SPS and TBT provisions affect multinational production in the food, beverages and tobacco industry. To this end, we combine two different databases to estimate, in a panel gravity framework, both the intensive and extensive margins of multinational production. Because the extensive margin of multinational production may be persistent, a dynamic probit specification is used. Our results show that legally enforceable SPS sections in RTAs, in particular, influence multinational production, though with a rather differentiated pattern in terms of intensive and extensive margins; further, the impact changes depending on the country of origin and destination. [ABSTRACT FROM AUTHOR]

Developing high‐performance carbonaceous anode materials for sodium‐ion batteries (SIBs) is still a grand quest for a more sustainable future of energy storage. Introducing sulfur within a carbon framework is one of the most promising attempts toward the development of highly efficient anode materials. Herein, a microporous sulfur‐rich carbon anode obtained from a liquid sulfur‐containing oligomer is introduced. The sodium storage mechanism shifts from surface‐controlled to diffusion‐controlled at higher synthesis temperatures. The different storage mechanisms and electrode performances are found to be independent of the bare electrode material's interplanar spacing. Therefore, these differences are attributed to an increased microporosity and a thiophene‐rich chemical environment. The combination of these properties enables extending the plateau region to higher potential and achieving reversible overpotential sodium storage. Moreover, in‐operando small‐angle X‐ray scattering (SAXS) reveals reversible electron density variations within the pore structure, in good agreement with the pore‐filling sodium storage mechanism occurring in hard carbons (HCs). Eventually, the depicted framework will enable the design of high‐performance anode materials for sodium‐ion batteries with competitive energy density. [ABSTRACT FROM AUTHOR]

Magnetotactic bacteria produce magnetite nanoparticles called magnetosomes at ambient conditions via a protein‐stabilized transient amorphous precursor to obtain precise control over particle size and morphology. In a bioinspired approach, such biomineralization processes are emulated, mimicking proteins involved in magnetosome formation using the positively charged analog poly‐L‐arginine. While the additive is expensive, it remains elusive whether the change in magnetite formation mechanism arises solely from the polymer's cationic nature. This study uses different mass‐produced and sustainably sourced polycations to induce the biomineralization‐reminiscent formation of magnetite nanoparticles. These findings present how to achieve control over nanoparticle size (from 10 to 159 nm) and morphology (compact and sub‐structured) as well as magnetic properties (superparamagnetic, stable‐single‐domain, vortex state) at ambient temperature and pressure using these additives. Furthermore, the formation of large nanoparticles with the addition of poly(diallyldimethylammonium chloride) (PDADMAC) at low alkalinity highlights how magnetotactic bacteria may produce magnetite nanoparticles under similar conditions. Confirming the polycations' ability to electrostatic stabilize amorphous ferrihydrite, it is anticipated that parametric in vitro studies on polymer properties will provide valuable insights into magnetite biomineralization and aid in rationally designing magnetic nanomaterials. [ABSTRACT FROM AUTHOR]

Zebra and quagga mussels (Dreissena spp.) are invasive freshwater biofoulers that perpetrate devastating economic and ecological impact. Their success depends on their ability to anchor onto substrates with protein-based fibers known as byssal threads. Yet, compared to other mussel lineages, little is understood about the proteins comprising their fibers or their evolutionary history. Here, we investigated the hierarchical protein structure of Dreissenid byssal threads and the process by which they are fabricated. Unique among bivalves, we found that threads possess a predominantly β-sheet crystalline structure reminiscent of spider silk. Further analysis revealed unexpectedly that the Dreissenid thread protein precursors are mechanoresponsive a-helical proteins that are mechanically processed into β-crystallites during thread formation. Proteomic analysis of the byssus secretory organ and byssus fibers revealed a family of ultrahigh molecular weight (354 to 467 kDa) asparagine-rich (19 to 20%) protein precursors predicted to form a-helical coiled coils. Moreover, several independent lines of evidence indicate that the ancestral predecessor of these proteins was likely acquired via horizontal gene transfer. This chance evolutionary event that transpired at least 12 Mya has endowed Dreissenids with a distinctive and effective fiber formation mechanism, contributing significantly to their success as invasive species and possibly, inspiring new materials design. [ABSTRACT FROM AUTHOR]

We analyse the Blume–Emery–Griffiths (BEG) model on the lattice Z d on the ferromagnetic-antiquadrupolar-disordered (FAD) point and on the antiquadrupolar-disordered (AD) line. In our analysis on the FAD point, we introduce a Gibbs sampler of the ground states at zero temperature, and we exploit it in two different ways: first, we perform via perfect sampling an empirical evaluation of the spontaneous magnetization at zero temperature, finding a non-zero value in d = 3 and a vanishing value in d = 2 . Second, using a careful coupling with the Bernoulli site percolation model in d = 2 , we prove rigorously that under imposing + boundary conditions, the magnetization in the center of a square box tends to zero in the thermodynamical limit and the two-point correlations decay exponentially. Also, using again a coupling argument, we show that there exists a unique zero-temperature infinite-volume Gibbs measure for the BEG. In our analysis of the AD line we restrict ourselves to d = 2 and, by comparing the BEG model with a Bernoulli site percolation in a matching graph of Z 2 , we get a condition for the vanishing of the infinite-volume limit magnetization improving, for low temperatures, earlier results obtained via expansion techniques. [ABSTRACT FROM AUTHOR]

We define a class of Markovian parallel dynamics for spin systems on arbitrary graphs with nearest neighbor interaction described by a Hamiltonian function H (σ) . These dynamics turn out to be reversible and their stationary measure is explicitly determined. Convergence to equilibrium and relation of the stationary measure to the usual Gibbs measure are discussed when the dynamics is defined on Z 2 . Further it is shown how these dynamics can be used to define natively parallel algorithms to face problems in the context of combinatorial optimization. [ABSTRACT FROM AUTHOR]

The inventory of the taxa collected in 2022 during the annual field trip of the Working Group for Floristics, Systematics and Evolution of the Italian Botanical Society is reported. The field trip was held from 19th to 22th April in the islands of Lipari and Panarea (Aeolian Islands, Sicilia). Overall, 1,664 herbarium specimens were deposited in public and private herbaria. The flora documented for the studied area amounts to 386 specific and subspecific taxa, belonging to 241 genera and 74 families. Centaurea aeolica, Helichrysum litoreum (Asteraceae), and Dianthus rupicola subsp. aeolicus (Caryophyllaceae) were the only three Italian endemics found in the study area, whereas 48 alien taxa were recorded. Dimorphotheca ecklonis (Asteraceae), Nassella tenuissima (Poaceae), Solanum torvum (Solanaceae), and Viola wittrockiana (Violaceae) are casual alien species new to Sicilia, whereas Oenothera odorata (Onagraceae) is a new naturalized alien species for the Italian vascular flora. [ABSTRACT FROM AUTHOR]

We consider a continuous system of classical particles confined in a cubic box Λ interacting through a stable and finite range pair potential with an attractive tail. We study the Mayer series of the grand canonical pressure of the system p Λ ω (β , λ) at inverse temperature β and fugacity λ in the presence of boundary conditions ω belonging to a very large class of locally finite particle configurations. This class of allowed boundary conditions is the basis for any probability measure on the space of locally finite particle configurations satisfying the Ruelle estimates. We show that the p Λ ω (β , λ) can be written as the sum of two terms. The first term, which is analytic and bounded as the fugacity λ varies in a Λ-independent and ω-independent disk, coincides with the free-boundary-condition pressure in the thermodynamic limit. The second term, analytic in a ω-dependent convergence radius, goes to zero in the thermodynamic limit. As far as we know, this is the first rigorous analysis of the behavior of the Mayer series of a non-ideal gas subjected to non-free and non-periodic boundary conditions in the low-density/high-temperature regime when particles interact through a non-purely repulsive pair potential. [ABSTRACT FROM AUTHOR]

Individuals with Down syndrome (DS) are at increased risk for being overweight/obese, but the associated cardiometabolic risk (CR) is not clear. Cross‐sectional anthropometric and clinical laboratory data from a multi‐site, international cohort of individuals with DS were analyzed to determine cardiometabolic risk by reporting observed distributions of cardiometabolic biomarkers in overweight/obese individuals with DS throughout the lifespan. Descriptive statistics and regression analyses by age categories determined the distributive percentiles for cardiometabolic biomarkers and tested for adiposity as a predictor of CR. Across seven DS clinics, data were collected on 240 patients between the ages of 3 and 63 years, with one quarter overweight and three quarters obese among children and nearly all adults being obese. In children and adults, most cardiometabolic biomarker profiles showed distributive values within normal ranges. Blood lipids were positively associated with body mass index (BMI) in children (high density lipid‐cholesterol, p = 0.01; low density lipid‐cholesterol, p = 0.02). Levels of hs‐CRP were elevated in both children and adults, with BMI positively associated with hs‐CRP in adults with DS (p = 0.04). Liver enzyme values were positively associated with BMI in children and adults. The data suggest that in contrast to the general population, in individuals with Down syndrome, being overweight and obese does not appear to confer a significantly increased risk for cardiometabolic disease by biomarker profile. Individuals with DS who are overweight/obese appear to have unique cardiometabolic profiles unrelated to adiposity, notable for increased hs‐CRP and normal HA1c levels. [ABSTRACT FROM AUTHOR]

Background: Immune checkpoint inhibitor hypophysitis (IIHs) is an emerging problem in cancer patients treated with immune checkpoint inhibitors (ICIs). We aimed to describe the clinical and molecular features of a multicenter series of IIHs. Methods: Demographic and clinical features were retrospectively collected for all cases. Anti-pituitary and anti-hypothalamus autoantibodies were also measured. Results: Nine patients were included. Six patients were treated with nivolumab and three with ipilimumab. Secondary hypoadrenalism was diagnosed in all patients. Pituitary MRI showed pituitary enlargement in two cases and no abnormalities in the other seven. Anti-pituitary antibodies were positive in 57.1% of cases and anti-hypothalamus antibodies in 85.7% of cases. Multidisciplinary treatments were established by a neuroendocrinologist and oncologists: all patients were treated with hydrocortisone replacement; ICI was withdrawn in two cases. At follow-up, hypoadrenalism persisted in all cases. Pituitary enlargement on MRI spontaneously recovered in the two affected patients. We found that the typical features of hypophysitis involved more frequently females and patients treated with ipilimumab. Conclusions: Although this study did not clarify if autoimmune secondary hypoadrenalism and ICI hypophysitis on brain imaging are two sides of the same disease, our preliminary data underline the need for molecular studies of IIHs and of autoimmune ICIs-related hypopituitarism. [ABSTRACT FROM AUTHOR]

Ambient pressure drying (APD) can prospectively reduce the costs of aerogel fabrication and processing. APD relies solely on preventing shrinkage or making it reversible. The latter, i.e., the aerogel re-expansion after drying (so-called springback effect—SBE), needs to be controlled for reproducible aerogel fabrication by APD. This can be achieved by an appropriate surface functionalization of aerogel materials (e.g., SiO2). This work addresses the fabrication of monolithic SiO2 aerogels and xerogels by APD. The effect of several silylation agents, i.e., trimethylchlorosilane, triethylchlorosilane, and hexamethyldisilazane on the SBE is studied in detail, applying several complementary experimental techniques, allowing the evaluation of the macroscopic and microscopic morphology as well as the composition of SiO2 aerogels. Here, we show that some physical properties, e.g., the bulk density, the macroscopic structure, and pore sizes/volumes, were significantly affected by the re-expansion. However, silylation did not necessarily lead to full re-expansion. Therefore, similarities in the molecular composition could not be equated to similarities in the SBE. The influences of steric hindrance and reactivity are discussed. The impact of silylation is crucial in tailoring the SBE and, as a result, the APD of monolithic aerogels. [ABSTRACT FROM AUTHOR]

Introduction: Obesity is a global pandemic and is cause of serious concern in all regions of the world. It is important to raise the attention of health care professionals in order to provide early treatment of patients with obesity. Obesity management, however, varies greatly amongst endocrinologists with respect to attitudes to diagnosis and treatment. Aim of this study was to identify practices and needs of Italian endocrinologists with respect to people with obesity. Methods: In this study, all members of the Italian Association of Clinical Endocrinologists (AME) were invited to participate in a web-based survey concerning the management of obesity. Results: The response rate was 24.1% (542/2248). Nutritional and obesity problems were reported as major areas of interest by 29.4% of the participants. A large proportion of patients seeking an endocrine consultation for other reasons are affected by obesity, but one in five respondents addressed the issue in 25% or less of the cases, while one in three always dealt with the problem. Obesity was managed personally/within a dedicated team by 42.6% of participants, while the remainders referred the patient to a dietician/ nutritionist or a 2nd level center for obesity therapy. Metformin was used in a median of 30% of the patients (Interquartile range: 10-50) and liraglutide in 10% of the cases (IQR 0-30), while orlistat (median 0%; IQR 0-10) and naltrexone/ bupropion (median 0%; IQR 0-5) were seldom prescribed. Cost of therapy was considered as the major limitation to the use of anti-obesity drugs, affecting adherence to long-term treatment. According to 41.9% of respondents, psychological support should be offered to all patients with obesity. Finally, 56% of participants believe that the availability of new drugs will increase the number of patients candidate to drug therapy. Discussion: In conclusion, it is of primary importance to raise the awareness of endocrinologists towards the problem of obesity and increase their confidence in managing this pathological condition. [ABSTRACT FROM AUTHOR]

X-rays are invaluable for imaging and sterilization of bones, yet the resulting ionization and primary radiation damage mechanisms are poorly understood. Here we monitor in-situ collagen backbone degradation in dry bones using second-harmonic-generation and X-ray diffraction. Collagen breaks down by cascades of photon-electron excitations, enhanced by the presence of mineral nanoparticles. We observe protein disintegration with increasing exposure, detected as residual strain relaxation in pre-stressed apatite nanocrystals. Damage rapidly grows from the onset of irradiation, suggesting that there is no minimal 'safe' dose that bone collagen can sustain. Ionization of calcium and phosphorous in the nanocrystals yields fluorescence and high energy electrons giving rise to structural damage that spreads beyond regions directly illuminated by the incident radiation. Our findings highlight photoelectrons as major agents of damage to bone collagen with implications to all situations where bones are irradiated by hard X-rays and in particular for small-beam mineralized collagen fiber investigations. X-rays are used for imaging and sterilisation of bone but cause damage due to ionising radiation. Here, the authors study the degradation of collagen caused by photon-electron excitations and show that damage is initiated from onset which has implications for X-ray imaging and the levels of safe exposure. [ABSTRACT FROM AUTHOR]

The lateral eyes of the horseshoe crab, Limulus polyphemus, are the largest compound eyes within recent Arthropoda. The cornea of these eyes contains hundreds of inward projecting elongated cuticular cones and concentrate light onto proximal photoreceptor cells. Although this visual system has been extensively studied before, the precise mechanism allowing vision has remained controversial. Correlating high‐resolution quantitative refractive index (RI) mapping and structural analysis, it is demonstrated how gradients of RI in the cornea stem from structural and compositional gradients in the cornea. In particular, these RI variations result from the chitin‐protein fibers architecture, heterogeneity in protein composition, and bromine doping, as well as spatial variation in water content resulting from matrix cross‐linking on the one hand and cuticle porosity on the other hand. Combining the realistic cornea structure and measured RI gradients with full‐wave optical modeling and ray tracing, it is revealed that the light collection mechanism switches from refraction‐based graded index (GRIN) optics at normal light incidence to combined GRIN and total internal reflection mechanism at high incident angles. The optical properties of the cornea are governed by different mechanisms at different hierarchical levels, demonstrating the remarkable versatility of arthropod cuticle. [ABSTRACT FROM AUTHOR]

Multiple Sclerosis (MS) is a chronic pathological condition representing one of the main causes of neurological disability in the female young population. MS, as an immune disorder, could impact fetus development, and, considering the need for and the possibility of pharmacological treatment during pregnancy, the possible influence of medication on developmental trajectories represents a topic of great interest. We provide an overview of the available literature on the influence of maternal Multiple Sclerosis on offspring cognitive and behavioral development. A study was conducted on Pubmed, Medline and Google Scholar, considering empirical studies and reviews exclusively in the English language. Maternal MS appears not to be associated with emotional and behavioral problems, as evaluated through retrospective studies. However, a specific cognitive and behavioral phenotype, through the administration of standardized instruments, has not been delineated yet. Available studies on the topic are characterized by poor methodology and do not lead to conclusions. This overview highlights implications for further longitudinal studies which should delineate offspring developmental trajectories, taking into consideration maternal confounding factors and the exposure to pharmacological treatment in pregnancy. [ABSTRACT FROM AUTHOR]

Non-alcoholic fatty liver disease (NAFLD)-related liver fibrosis results in the encapsulation of injured liver parenchyma by a collagenous scar mainly imputable to hepatic stellate cells' activation. Approved pharmacological treatments against NAFLD-related fibrosis are still lacking, but natural compounds such as hydroxytyrosol (HXT) and vitamin E (VitE), are emerging as promising therapeutic opportunities. In this study, the potential anti-fibrotic effect of HXT + VitE combination therapy was investigated in vitro and in vivo. In particular, tumor growth factor (TGF)-β-activated LX-2 cells as an in vitro model, and carbon tetrachloride plus a Western diet as a mice model were employed. The effect of HXT + VitE on fibrosis was also investigated in children with biopsy-proven NAFLD. Our results demonstrated that HXT + VitE caused a reduction of proliferation, migration, contractility, and expression of pro-fibrogenic genes in TGF-β-activated LX-2 cells. HXT + VitE treatment also antagonized TGF-β-dependent upregulation of pro-oxidant NOX2 by interfering with nuclear translocation/activation of SMAD2/3 transcription factors. The mouse model of NAFLD-related fibrosis treated with HXT + VitE showed a marked reduction of fibrosis pattern by histology and gene expression. Accordingly, in children with NAFLD, HXT + VitE treatment caused a decrease of circulating levels of PIIINP and NOX2 that was supported over time. Our study suggests that HXT + VitE supplementation may improve NAFLD-related fibrosis. [ABSTRACT FROM AUTHOR]

Sleep is a major concern, especially in people with Down Syndrome (DS). Beyond Obstructive Sleep Apnea, a number of other sleep difficulties have been reported in children with DS, such as delayed sleep onset, night-time awakenings, and early morning awakenings. The detrimental effect of sleep difficulties seems to contribute to and exacerbate the cognitive and behavioral outcomes of DS. Although the screening for sleep disorders is recommended early in age in DS, only a few studies have evaluated the sleep profile in preschool-age children with DS. The aim of the current study was to assess the association between sleep disturbances and behavioral problems in a group of preschool-age children with DS, by means of a feasible and easy-to-administer parent-report questionnaires. Seventy-one preschool-age children with DS, ranging in age from 3 to 5.11 years, were included in this retrospective study. Sleep disturbances were evaluated by means of the Sleep Disturbance Scale for Children, while emotional and behavioral problems by means of the Child Behavior Checklist. Sleep breathing disorders were the most frequent sleep difficulties reported by parents. Moreover, children with clinical scores in total sleep problems exhibited elevation of psychopathological symptoms, namely Total problems, Affective problems, Anxiety problems, Pervasive Developmental Problems, and Attention Deficit/Hyperactivity Problems. The identification of the broader connection between sleep difficulties and emotional and behavioral problems in preschoolage children with DS leads to important considerations for intervention. [ABSTRACT FROM AUTHOR]

ASD is a neurodevelopmental disorder of unknown aetiology but with a known contribution of pathogenic immune-mediated mechanisms. HERVs are associated with several neuropsychiatric diseases, including ASD. We studied anti-HERV-W, -K and -H-env immune profiles in ASD children to analyse differences between their respective mothers and child/mother control pairs and possible correlations to ASD severity and loss of adaptive abilities. Of the 84 studied individuals, 42 children (23 ASD and 19 neurotypical) and their paired mothers underwent clinical and neuropsychological evaluations. ASD severity was analysed with standardised tests. Adaptive functioning was studied with ABAS-II and GAC index. Plasma anti-env responses of HERV-K, -H and -W were tested with indirect ELISA. ASD and neurotypical children did not differ in age, gender, comorbidities and anti-HERV responses. In children with ASD, anti-HERV levels were not correlated to ASD severity, while a significant inverse correlation was found between anti-HERV-W-248-262 levels and adaptive/social abilities. Upregulation of anti-HERV-W response correlates to dysfunctional social and adaptive competences in ASD but not in controls, suggesting anti-HERV response plays a role in the appearance of peculiar ASD symptoms. [ABSTRACT FROM AUTHOR]

Lipid structural diversity strongly affects biomembrane chemico-physical and structural properties in addition to membrane-associated events. At high concentrations, cholesterol increases membrane order and rigidity, while polyunsaturated lipids are reported to increase disorder and flexibility. How these different tendencies balance in composite bilayers is still controversial. In this study, electron paramagnetic resonance spectroscopy, small angle neutron scattering, and neutron reflectivity were used to investigate the structural properties of cholesterol-containing lipid bilayers in the fluid state with increasing amounts of polyunsaturated omega-3 lipids. Either the hybrid 1-stearoyl-2-docosahexaenoyl-sn-glycero-3-phosphocholine or the symmetric 1,2-docosahexaenoyl-sn-glycero-3-phosphocholine were added to the mixture of the naturally abundant 1-palmitoyl-2-oleyl-sn-glycero-3-phosphocholine and cholesterol. Our results indicate that the hybrid and the symmetric omega-3 phospholipids affect the microscopic organization of lipid bilayers differently. Cholesterol does not segregate from polyunsaturated phospholipids and, through interactions with them, is able to suppress the formation of non-lamellar structures induced by the symmetric polyunsaturated lipid. However, this order/disorder balance leads to a bilayer whose structural organization cannot be ascribed to either a liquid ordered or to a canonical liquid disordered phase, in that it displays a very loose packing of the intermediate segments of lipid chains. [ABSTRACT FROM AUTHOR]

Viola sect. Melanium, the so-called pansy, is an allopolyploid morphologically well-defined lineage of ca. 110 perennial and annual species in the northern hemisphere, characterized by markedly complex genomic configurations. Five annual pansies occur in Italy, four of which are morphologically very similar and belong to the informal 'V. tricolor species complex': V. arvensis (2n = 34), V. hymettia (2n = 16), V. kitaibeliana (2n = 16), and V. tricolor (2n = 26). Their field recognition is difficult and reflects a long-debated taxonomy often resulting in doubtful records in field inventories and across European herbaria. The current lack of comprehensive intra- and interspecific comparative studies and a relative scarcity of appropriate genetic markers coupled with unambiguous cytological descriptions are hindering clear taxa circumscription and phylogenetic inferences within this group. In this work, we tested DNA sequence variation of three highly variable plastid markers and High-Throughput Sequencing (HTS) of the nuclear ribosomal 5S-IGS region in an attempt to decipher species identity within the V. tricolor species complex and to obtain an insight on their genome organization and evolution. Our results document the close relationships within this species group, a reliable molecular resolution for V. tricolor, and the common ancestry of V. arvensis and the poorly differentiated V. kitaibeliana and V. hymettia. Evidence of an important inter-population geographical divergence was recorded in V. tricolor and V. arvensis, pointing at the existence of different eco-cytotypes within these entities. Overall diversity patterns and the occurrence of two to four differently diverging 5S-IGS lineages are discussed in the light of the acknowledged taxonomy and genomic evolutive trajectories of sect. Melanium. [ABSTRACT FROM AUTHOR]

A new hetero‐bimetallic polyoxometalate (POM) nano‐ring was synthesized in a one‐pot procedure. The structure consists of tetrameric units containing four bismuth‐substituted monolacunary Keggin anions including distorted [BiO8] cubes. The nano‐ring is formed via self‐assembly from metal precursors in aqueous acidic medium. The compound (NH4)16[(BiPMo11O39)4] ⋅ 22 H2O; (P4Bi4Mo44) was characterized by single‐crystal X‐ray diffraction, extended X‐ray absorption fine structure spectroscopy (EXAFS), Raman spectroscopy, matrix‐assisted laser desorption/ionisation‐time of flight mass spectrometry (MALDI‐TOF), and thermogravimetry/differential scanning calorimetry mass spectrometry (TG‐DSC‐MS). The formation of the nano‐ring in solution was studied by time‐resolved in situ small‐ and wide‐angle X‐ray scattering (SAXS/WAXS) and in situ EXAFS measurements at the Mo−K and the Bi−L3 edge indicating a two‐step process consisting of condensation of Mo‐anions and formation of Bi−Mo‐units followed by a rapid self‐assembly to yield the final tetrameric ring structure. [ABSTRACT FROM AUTHOR]

The springback effect during ambient pressure drying of aerogels is an interesting structural phenomenon, consisting of a severe shrinkage followed by almost complete re-expansion. The drying of gels causes shrinkage, whereas re-expansion is believed to be linked to repelling forces on the nanoscale. A multi-scale structural characterization of this significant volume change is key in controlling aerogel processing and properties. In this work, hydrophobic, monolithic silica aerogels with high specific surface areas were synthesized by modification with trimethylchlorosilane and ambient pressure drying. Here, we report a multi-method approach focusing on in-situ X-ray scattering to observe alterations of the nanostructured material during the drying of surface-modified and unmodified silica gels. Both show a porous fractal nanostructure, which partially collapses during drying and only recovers in surface-modified samples during the springback effect. Distinct changes of the X-ray scattering data were reproducibly associated with the shrinkage, re-expansion and drying of the gel network. Our findings may contribute to tailor aerogels with specific functionality, as the springback effect has a direct influence on properties (e.g., porosity, pore size distribution), which is directly affected by the degree of re-expansion. [ABSTRACT FROM AUTHOR]

We discuss a model describing the effects of tidal dissipation on the satellite's orbit in the two-body problem. Tidal bulges are described in terms of a dumbbell, coupled to the rotation by a dissipative interaction. The assumptions on this dissipative coupling turn out to be crucial in the evolution of the system. [ABSTRACT FROM AUTHOR]

In this paper we propose a notion of stability, which we call ε - N -stability, for systems of particles interacting via Newton's gravitational potential, and orbiting a much bigger object. For these systems the usual thermodynamical stability condition, ensuring the possibility to perform the thermodynamical limit, fails, but one can use as relevant parameter the maximum number of particles N that guarantees the ε - N -stability. With some judicious but not particularly optimized estimates, borrowed from the classical theory of equilibrium statistical mechanics, we show that our model has a good fit with the data observed in the Solar System, and it gives a reasonable interpretation of some of its global properties. [ABSTRACT FROM AUTHOR]

SUMMARY: Standard models of plant speciation assume strictly dichotomous genealogies in which a species, the ancestor, is replaced by two offspring species. The reality in wind‐pollinated trees with long evolutionary histories is more complex: species evolve from other species through isolation when genetic drift exceeds gene flow; lineage mixing can give rise to new species (hybrid taxa such as nothospecies and allopolyploids). The multi‐copy, potentially multi‐locus 5S rDNA is one of few gene regions conserving signal from dichotomous and reticulate evolutionary processes down to the level of intra‐genomic recombination. Therefore, it can provide unique insights into the dynamic speciation processes of lineages that diversified tens of millions of years ago. Here, we provide the first high‐throughput sequencing (HTS) of the 5S intergenic spacers (5S‐IGS) for a lineage of wind‐pollinated subtropical to temperate trees, the Fagus crenata – F. sylvatica s.l. lineage, and its distant relative F. japonica. The observed 4963 unique 5S‐IGS variants reflect a complex history of hybrid origins, lineage sorting, mixing via secondary gene flow, and intra‐genomic competition between two or more paralogous‐homoeologous 5S rDNA lineages. We show that modern species are genetic mosaics and represent a striking case of ongoing reticulate evolution during the past 55 million years. Significance Statement: The evolution of extra‐tropical wind‐pollinated tree genera involves dynamic speciation processes. High‐throughput sequencing of the multi‐copy, potentially multi‐locus 5S rDNA reveals a complex history of hybrid origins, lineage sorting and mixing, and intra‐genomic competition between paralogous‐homeologous loci in the core group of Eurasian beech trees (genus Fagus) and their distant relative, F. japonica. The modern species are genetic mosaics and represent a striking case of at least 55 million years of ongoing reticulate evolution. [ABSTRACT FROM AUTHOR]

The recent wave of foreign land acquisitions (FLA) has raised several concerns in terms of their environmental and social sustainability. An unexplored issue is whether pollution‐haven mechanisms are driving the pattern of FLA. This paper investigates whether and how differences in environmental stringency between investing and target country affect the pattern of FLA. We estimate a panel gravity equation and use different indexes to measure the environmental stringency. Our results show that, by and large, differences in environmental stringency do affect FLA. The wider the gap in the environmental stringency between the investor and the target country, the higher is the number of firms investing abroad. Our results also show that the impact of environmental stringency differentials on FLA depends on the investor country and on corruption in the target country, and that in a number of estimations the choice over the index of stringency may be a relevant factor. [ABSTRACT FROM AUTHOR]

Biofilms are multicellular microbial communities that encase themselves in an extracellular matrix (ECM) of secreted biopolymers and attach to surfaces and interfaces. Bacterial biofilms are detrimental in hospital and industrial settings, but they can be beneficial, for example, in agricultural as well as in food technology contexts. An essential property of biofilms that grants them with increased survival relative to planktonic cells is phenotypic heterogeneity, the division of the biofilm population into functionally distinct subgroups of cells. Phenotypic heterogeneity in biofilms can be traced to the cellular level; however, the molecular structures and elemental distribution across whole biofilms, as well as possible linkages between them, remain unexplored. Mapping X-ray diffraction across intact biofilms in time and space, we revealed the dominant structural features in Bacillus subtilis biofilms, stemming from matrix components, spores, and water. By simultaneously following the X-ray fluorescence signal of biofilms and isolated matrix components, we discovered that the ECM preferentially binds calcium ions over other metal ions, specifically, zinc, manganese, and iron. These ions, remaining free to flow below macroscopic wrinkles that act as water channels, eventually accumulate and may possibly lead to sporulation. The possible link between ECM properties, regulation of metal ion distribution, and sporulation across whole, intact biofilms unravels the importance of molecular-level heterogeneity in shaping biofilm physiology and development. [ABSTRACT FROM AUTHOR]

In recent years, we have come to appreciate the astounding intricacies associated with the formation of minerals from ions in aqueous solutions. In this context, a number of studies have revealed that the nucleation of calcium sulfate systems occurs nonclassically, involving the aggregation and reorganization of nanosized prenucleation species. In recent work, we have shown that this particle-mediated nucleation pathway is actually imprinted in the resultant micrometer-sized CaSO4 crystals. This property of CaSO4 minerals provides us with the unique opportunity to search for evidence of nonclassical nucleation pathways in geological environments. In particular, we focused on large anhydrite crystals extracted from the Naica Mine in Mexico. We were able to shed light on this mineral's growth history by mapping defects at different length scales. Based on this, we argue that the nanoscale misalignment of the structural subunits, observed in the initial calcium sulfate crystal seeds, propagates through different length scales both in morphological, as well as in strictly crystallographic aspects, eventually causing the formation of large mesostructured single crystals of anhydrite. Hence, the nonclassical nucleation mechanism introduces a “seed of imperfection,” which leads to a macroscopic “single” crystal whose fragments do not fit together at different length scales in a self-similar manner. Consequently, anisotropic voids of various sizes are formed with very welldefined walls/edges. However, at the same time, the material retains in part its single crystal nature. [ABSTRACT FROM AUTHOR]

The notion of rigid commutators is introduced to determine the sequence of the logarithms of the indices of a certain normalizer chain in the Sylow 2-subgroup of the symmetric group on 2 n letters. The terms of this sequence are proved to be those of the partial sums of the partitions of an integer into at least two distinct parts, that relates to a famous Euler's partition theorem. [ABSTRACT FROM AUTHOR]

On the basis of an initial interest in symmetric cryptography, in the present work we study a chain of subgroups. Starting from a Sylow 2-subgroup of AGL (2 , n) , each term of the chain is defined as the normalizer of the previous one in the symmetric group on 2 n letters. Partial results and computational experiments lead us to conjecture that, for large values of n, the index of a normalizer in the consecutive one does not depend on n. Indeed, there is a strong evidence that the sequence of the logarithms of such indices coincides with the sequence of the partial sums of the numbers of partitions into at least two distinct parts. [ABSTRACT FROM AUTHOR]

The assessment of the ecosystem state is fundamental to understand the success of ecological rehabilitation, especially in the long term. We aim to evaluate the rehabilitation success of a unique Mediterranean dune system site along the Tyrrhenian coast of Italy which underwent a dune consolidation intervention and species planting at the beginning of the twentieth century after the destruction of the natural ecosystem. We used three nearby non‐rehabilitated protected coastal sites with different degrees of disturbance as reference sites encompassing different potential rehabilitation outcomes of the target site. To assess the overall result of the intervention, we used several plant characteristics and measured taxonomic and functional beta‐diversity between all sites. We compared the proportions of typical and ruderal species of dune habitat types across sites. We further used the species–area relationship to examine if the number of observed species in our sites differed from the expected. Our analyses revealed that the rehabilitated site was taxonomically and functionally more similar to the least disturbed site. We suggest that plant characteristics arising from botanical inventories can be fruitfully used in rehabilitation assessment as they value the taxonomic and functional species diversity at the community scale. We conclude that plant characteristics compared across sites are useful tools in ecosystem state assessment if they reflect the ecological functions and conservation values of the natural ecosystems. [ABSTRACT FROM AUTHOR]

This paper reviews the state-of-the-art work on agri-food Multinational Enterprises (MNEs), by discussing the current state-of-play and the tools at our disposal to expand knowledge. After a critical discussion of available data, new data from OECD are used to provide a broad overview of the role of MNEs in the agri-food Global Value Chains (GVCs) and to draw a few stylized facts. Data reveals that in the food, beverages and tobacco industry MNE activity is higher than on average, while in agriculture it is lower; North-South flows are increasing as well as the role of MNE in the agri-food GVCs. The review of theoretical and of empirical literature shows how modern trade theories provide us with a strong theoretical background which, together with improved firm-level and country-level data, may help explaining observed patterns and effectively orientate empirical analyses of agri-food MNEs in several directions. [ABSTRACT FROM AUTHOR]

On the space of Ising configurations on the 2-d square lattice, we consider a family of non Gibbsian measures introduced by using a pair Hamiltonian, depending on an additional inertial parameter q. These measures are related to the usual Gibbs measure on Z 2 and turn out to be the marginal of the Gibbs measure of a suitable Ising model on the hexagonal lattice. The inertial parameter q tunes the geometry of the system. The critical behaviour and the decay of correlation functions of these measures are studied thanks to relation with the Random Cluster model. This measure turns out to be interesting also because it is the stationary measure of a class of Probabilistic Cellular Automata (PCA). Such PCA can be used to obtain a fast sample of the Ising measures on 2-d lattices. [ABSTRACT FROM AUTHOR]

Background: Glucose-transporter-1 deficiency syndrome (GLUT1-DS), due to SLC2A1 gene mutation, is characterized by early-onset seizures, which are often drug-resistant, developmental delay, and hypotonia. Hemiplegic migraine (HM) is a rare form of migraine, defined by headache associated with transient hemiplegia, and can be caused by mutations in either CACNA1A, ATP1A2 , or SCN1A. Paroxysmal movements, other transient neurological disorders, or hemiplegic events can occur in GLUT1-DS patients with a mild phenotype. Case: We report on a girl with GLUT1-DS, due to SLC2A1 mutation, with a mild phenotype. In early childhood, she developed epilepsy and mild cognitive impairment, balance disorders, and clumsiness. At the age of 9, the patient reported a first hemiplegic episode, which regressed spontaneously. Over the next 3 years, two similar episodes occurred, accompanied by headache. Therefore, in the hypothesis of HM, genetic testing was performed and CACNA1A mutation was identified. The treatment with Lamotrigine avoided the recurrence of HM episodes. Discussion: To our knowledge, among the several cases of GLUT1-DS with HM symptoms described in the literature, genetic testing was only performed in two of them, which eventually proved to be negative. In all other cases, no other genes except for SLC2A1 were examined. Consequently, our patient would be the first description of GLUT1-DS with HM due to CACNA1A mutation. We would emphasize the importance of performing specific genetic testing in patients with GLUT1-DS with symptoms evocative of HM, which may allow clinicians to use specific pharmacotherapy. [ABSTRACT FROM AUTHOR]

Background: Childhood neurodevelopmental disorders (NDDs), including specific learning disorders (SLD), attention deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD), are pathogenically linked to familial autoimmunity and maternal immune-mediated diseases during pregnancy. Objective: We studied maternal MS as a potential risk factor for NDDs occurrence in offspring. Methods: MS and control mothers were subjected to questionnaires to ascertain NDD diagnosis in their progeny and the occurrence of both autoimmune and neurodevelopment disorders in their families. Suspected NDD cases were evaluated to confirm or rule out the diagnosis. Results: Of the 322 MS women, 206 (64%) have 361 children; of these, 27 (7.5%) were diagnosed with NDD (11% ADHD; 22% ASD; 67% SLD). NDD-risk in offspring was associated to family history of autoimmunity and to NDDs both in MS and non-MS mother families (r = 0.75; p = 0.005) whereas it was not associated to maternal MS. Conclusions: For the first time, we demonstrate that maternal MS does not predispose children to higher risk for NDD. On a mechanistic view, we suggest that the intrinsic organ-specific nature of MS does not impair the mother–child cross-talk in decidua nor does it influence fetal neurodevelopment. [ABSTRACT FROM AUTHOR]

Background: Childhood neurodevelopmental disorders (NDDs), including specific learning disorders (SLD), attention deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD), are pathogenically linked to familial autoimmunity and maternal immune-mediated diseases during pregnancy. Objective: We studied maternal MS as a potential risk factor for NDDs occurrence in offspring. Methods: MS and control mothers were subjected to questionnaires to ascertain NDD diagnosis in their progeny and the occurrence of both autoimmune and neurodevelopment disorders in their families. Suspected NDD cases were evaluated to confirm or rule out the diagnosis. Results: Of the 322 MS women, 206 (64%) have 361 children; of these, 27 (7.5%) were diagnosed with NDD (11% ADHD; 22% ASD; 67% SLD). NDD-risk in offspring was associated to family history of autoimmunity and to NDDs both in MS and non-MS mother families (r = 0.75; p = 0.005) whereas it was not associated to maternal MS. Conclusions: For the first time, we demonstrate that maternal MS does not predispose children to higher risk for NDD. On a mechanistic view, we suggest that the intrinsic organ-specific nature of MS does not impair the mother–child cross-talk in decidua nor does it influence fetal neurodevelopment. [ABSTRACT FROM AUTHOR]

We present an alternative proof of the so-called First Visit Time Lemma (FVTL), originally presented by Cooper and Frieze in its first formulation in Cooper and Frieze (2005), and then used and refined in a list of papers by Cooper, Frieze and coauthors. We work in the original setting, considering a growing sequence of irreducible Markov chains on n states. We assume that the chain is rapidly mixing and with a stationary measure with no entry being either too small nor too large. Under these assumptions, the FVTL shows the exponential decay of the distribution of the hitting time of a given state x--for the chain started at stationarity--up to a small multiplicative correction. While the proof by Cooper and Frieze is based on tools from complex analysis, and it requires an additional assumption on a generating function, we present a completely probabilistic proof, relying on the theory of quasi-stationary distributions and on strong-stationary times arguments. In addition, under the same set of assumptions, we provide some quantitative control on the Doob's transform of the chain on the complement of the state x. [ABSTRACT FROM AUTHOR]

Gastridium P. Beauv. is a Mediterranean-Paleotropical member of the Poaceae family, whose species number and diversity are still imperfectly known. We examined patterns of DNA diversity at two plastid (trnH-psbA, trnL-F) and one nuclear (ITS) DNA markers in 44 individuals of the four taxa (Gastridium lainzii, G. phleoides, G. scabrum, G. ventricosum) recently recognised by different authors, based on morpho-ecological descriptors. Diversity data were explored with multiple statistical and phylogenetic tools, and integrated with available GenBank sequences of Gastridium and closely related genera. Despite the limited variability detected, evidence of within-taxon genetic cohesion and estimates of molecular divergence comparable with those of species in the same subtribal lineage (Agrostidinae) were recovered. The identified plastid genealogies are congruent with a subdivision of the genus into four distinct species, coherently with collected morphological descriptors. Phylogenetic reconstructions with ITS were less corresponding to the four taxa, possibly due to reticulation and polyploidization. The broader plastid and nuclear tree topologies were consistent with previous assessments, highlighting the overall little resolution of species and genera within Agrostidinae, and the close relationships shared by Gastridium and Triplachne. The hypothesis of closely related, but separately evolving, lineages within Gastridium is discussed, suggesting a re-evaluation of its current taxonomy. [ABSTRACT FROM AUTHOR]

Autism spectrum disorder (ASD) is a neurodevelopmental disorder defined by deficits in social communication and stereotypical behaviours. ASD's aetiology remains mostly unclear, because of a complex interaction between genetic and environmental factors. Recently, a strong consensus has developed around ASD's immune‐mediated pathophysiology, which is the subject of this review. For many years, neuroimmunological studies tried to understand ASD as a prototypical antibody‐ or cell‐mediated disease. Other findings indicated the importance of autoimmune mechanisms such as familial and individual autoimmunity, adaptive immune abnormalities and the influence of infections during gestation. However, recent studies have challenged the idea that autism may be a classical autoimmune disease. Modern neurodevelopmental immunology shows the double‐edged nature of many immune effectors, which can be either beneficial or detrimental depending on tissue homeostasis, stressors, neurodevelopmental stage, inherited and de novo gene mutations and other variables. Nowadays, mother–child interactions in the prenatal environment appear to be crucial for the occurrence of ASD. Studies of animal maternal–foetal immune interaction are being fruitfully carried out using different combinations of type and timing of infection, of maternal immune response and foetal vulnerability and of resilience factors to hostile events. The derailed neuroimmune crosstalk through the placenta initiates and maintains a chronic foetal neuroglial activation, eventually causing the alteration of neurogenesis, migration, synapse formation and pruning. The importance of pregnancy can also allow early immune interventions, which can significantly reduce the increasing risk of ASD and its heavy social burden. [ABSTRACT FROM AUTHOR]

In this paper we analyse properties satisfied by certain open normal subgroups in normally constrained pro-p groups and in a spread version of normally constrained pro-p groups. In the case of powerful normally constrained pro-p groups, we exhibit some kind of inheritance properties in certain open normal subgroups. [ABSTRACT FROM AUTHOR]