Bootstrapped Newtonian stars and black holes

We study equilibrium configurations of a homogenous ball of matter in a bootstrapped description of gravity which includes a gravitational self-interaction term beyond the Newtonian coupling. Both matter density and pressure are accounted for as sources of the gravitational potential for test particles. Unlike the general relativistic case, no Buchdahl limit is found and the pressure can in principle support a star of arbitrarily large compactness. By defining the horizon as the location where the escape velocity of test particles equals the speed of light, like in Newtonian gravity, we find a minimum value of the compactness for which this occurs. The solutions for the gravitational potential here found could effectively describe the interior of macroscopic black holes in the quantum theory, as well as predict consequent deviations from general relativity in the strong field regime of very compact objects.Comment: 27 pages, 17 figures. Version accepted for publication in EPJ

Effective potentials for corpuscular black holes

L’approccio innovativo alla fisica dei buchi neri quantistici proposto da Dvali e Gomez, permette di trovare nuove soluzioni ad alcuni dei principali problemi dell’unione tra relatività generale e meccanica quantistica. In particolare, porta a un’interpretazione originale della geometria classica, che diventa un concetto emergente dalla descrizione della gravità attraverso uno stato quantistico di gravitoni con numero d’occupazione elevato. Queste idee sono la principale motivazione del nostro lavoro, che chiarisce alcuni aspetti delicati stabilendo un netto collegamento tra il modello quantistico corpuscolare di cui abbiamo appena parlato e la teoria della relatività di Einstein, in approssimazione post-Newtoniana. Questo studio si basa in particolare sulla ricerca di una descrizione quantistica effettiva del potenziale gravitazionale statico, per sistemi a simmetria sferica, al primo ordine non lineare nel limite di campo debole e velocità non relativistiche. Verifichiamo esplicitamente che il nostro modello recuperi i risultati classici per due diverse distribuzioni di materia (omogenea e gaussiana). Infine, procediamo alla quantizzazione del sistema e troviamo uno stato quantistico di gravitoni (virtuali) con le correzioni necessarie per riprodurre il potenziale post-Newtoniano

Quantum corpuscular corrections to the Newtonian potential

We study an effective quantum description of the static gravitational potential for spherically symmetric systems up to the first post-Newtonian order. We start by obtaining a Lagrangian for the gravitational potential coupled to a static matter source from the weak field expansion of the Einstein-Hilbert action. By analysing a few classical solutions of the resulting field equation, we show that our construction leads to the expected post-Newtonian expressions. Next, we show that one can reproduce the classical Newtonian results very accurately by employing a coherent quantum state and modifications to include the first post-Newtonian corrections are considered. Our findings establish a connection between the corpuscular model of black holes and post-Newtonian gravity, and set the stage for further investigations of these quantum models.Comment: 26 pages, 4 figures. Typos corrected, references and clarifications adde

The decline in muscle strength and muscle quality in relation to metabolic derangements in adult women with obesity

Background & aims: The metabolic and functional characteristics related to sarcopenic obesity have not been thoroughly explored in the earlier stages of the aging process. The aim of the present study was to examine the phenotype of sarcopenic obesity, in terms of lean body mass, muscle strength and quality, in adult women with and without the Metabolic Syndrome (MetS), and its relationship with the features of myosteatosis. Methods: Study participants were enrolled at the Sapienza University, Rome, Italy. Body composition was assessed by DXA. The Handgrip strength test (HGST) was performed. HGST was normalized to arm lean mass to indicate muscle quality; intermuscular adipose tissue (IMAT) and intramyocellular lipid content (IMCL) were measured by magnetic resonance imaging and spectroscopy, as indicators of myosteatosis. Different indices of sarcopenia were calculated, based on appendicular lean mass (ALM, kg) divided by height squared, or weight. The NCEP-ATPIII criteria were used to diagnose the MetS. HOMA-IR was calculated. The physical activity level (PAL) was assessed through the IPAQ questionnaire. Results: 54 women (age: 48 ± 14 years, BMI: 37.9 ± 5.4 kg/m 2 ) were included. 54% had the MetS (metabolically unhealthy, MUO). HGST/arm lean mass was lower in MUO women than women without the MetS (6.3 ± 1.8 vs. 7.8 ± 1.6, p = 0.03). No differences emerged in terms of absolute ALM (kg) or other indices of sarcopenia (ALM/h 2 or ALM/weight) between metabolically healthy (MHO) vs. MUO women (p > 0.05). Muscle quality was negatively associated with HOMA-IR (p = 0.02), after adjustment for age, body fat, hs-CRP levels, and PAL. IMAT, but not IMCL, was significantly higher in obese women with the MetS compared to women without the MetS (p > 0.05). No association emerged between HGST/arm lean mass and IMAT or IMCL when HOMA-IR was included in the models. Conclusion: Insulin resistance, and not sarcopenia or myosteatosis per se, was associated with muscle weakness, resulting in the phenotype of “dynapenic obesity” in middle-aged women with the metabolic syndrome

Cardiovascular abnormalities and impaired exercise performance in adolescents with congenital adrenal hyperplasia

Context: Patients with classic Congenital Adrenal Hyperplasia (CAH) are treated with lifelong glucocorticoids (GCS). Cardiovascular (CV) and metabolic effects of such therapy in adolescents have never been quantified. Objective: To investigate left ventricular (LV) morphology, function and exercise performance in adolescents with CAH. Design and Setting: cross-sectional and controlled study conducted at a tertiary referral centre. Patients: Twenty patients with classic CAH (10 females) aged 13.6±2.5 years and 20 healthy controls comparable for sex and pubertal status were enrolled in the study and compared to a group of 18 patients without CAH receiving a similar dose of GCS for Juvenile Idiopathic Arthritis (JIA). Main Outcomes Measures: Echocardiographic assessment and symptom-limited exercise testing were performed. Anthropometric, hormonal and biochemical parameters were also measured. Results: Compared to healthy controls, patients with CAH exhibited an increased BMI (p<0.001), waist-to-height ratio (p<0.001), percentage of body fat (p<0.001) as well as higher insulin concentrations and HOMA index even after adjustment for BMI (p=0.03 and p=0.05, respectively). Moreover, CAH patients exhibited an impaired exercise capacity as shown by reduced peak workload (99±27 vs 126±27 W, p<0.01) and higher systolic blood pressure response at peak (156±18 vs 132±11 mmHg, p<0.01; Δ=45±24 vs 22±10 mmHg, p=0.05) with respect to healthy controls. CAH males displayed mild LV diastolic dysfunction as documented by significant prolongation of both isovolumic relaxation time (IRT) (118±18 vs 98±11ms, p<0.05) and mitral deceleration time (MDT) (138±25 vs 111±15 ms, p<0.01). No significant differences in CV function were found between CAH and JIA patients. Conclusion: Adolescents with CAH exhibit impaired exercise performance and enhanced systolic blood pressure response during exercise. In our population, such abnormalities appear related to GCS therapy rather than CAH per se. CAH males, but no females, present mild LV diastolic dysfunction that correlates with testosterone concentrations suggesting a sex hormone related difference

Methamphetamine persistently increases alpha-synuclein and suppresses gene promoter methylation within striatal neurons

Abstract Methamphetamine (Meth) produces a variety of epigenetic effects in the brain, which are seminal to establish long-lasting alterations in neuronal activity. However, most epigenetic changes were described by measuring the rough amount of either histone acetylation and methylation or direct DNA methylation, without focusing on a specific DNA sequence. This point is key to comprehend Meth-induced phenotypic changes, brain plasticity, addiction and neurodegeneration. In this research paper we analyze the persistence of Meth-induced striatal synucleinopathy at a prolonged time interval of Meth withdrawal. At the same time, Meth-induced alterations, specifically within alpha-synuclein gene (SNCA) or its promoter, were evaluated. We found that exposure to high and/or prolonged doses of Meth, apart from producing nigro-striatal toxicity, determines a long-lasting increase in striatal alpha-synuclein levels. This is consistent along immune-blotting, immune-histochemistry, and electron microscopy. This was neither associated with an increase of SNCA copy number nor with alterations within SNCA sequence. However, we documented persistently demethylation within SNCA promoter, which matches the increase in alpha-synuclein protein. The amount of the native protein, which was measured stoichiometrically within striatal neurons, surpasses the increase reported following SNCA multiplications. Demethylation was remarkable (ten-fold of controls) and steady, even at prolonged time intervals being tested so far (up to 21 days of Meth withdrawal). Similarly alpha-synuclein protein assayed stoichiometrically steadily increased roughly ten-fold of controls. Meth-induced increase of alpha-synuclein was also described within limbic areas. These findings are discussed in the light of Meth-induced epigenetic changes, Meth-induced phenotype alterations, and Meth-induced neurodegeneration

Immediate functional loading of single implants: a multicenter study with 4 years of follow-up

Background: In the current scientific literature there are only few studies on the immediate functional loading of single implants. Aim: To present the 4-year survival rate, complication rate and peri-implant marginal bone loss (PIMBL) of immediately loaded single implants inserted in healed ridges and fresh post-extraction sites. Methods: Six centers were involved in this prospective study. The surgical and prosthetic protocol was defined in detail, before the start of recruiting patients. Recruitment of patients and performance of surgeries took place between February 2012 and February 2013. Criteria for inclusion were single-tooth gaps in healed ridges and fresh post-extraction sockets. All fixtures (Anyridge®, Megagen Corporation, Gyeongbuk, South Korea) were functionally loaded immediately after insertion and followed for a period of 4 years. Outcome measures were implant survival, complications, PIMBL. Results: Forthy-six patients (between 18 and 73 years of age) were selected. In total, 57 fixtures were placed (10 in fresh post-extraction sockets). After 4 years of functional loading, only one fixture was lost, therefore high survival rates (97.6% patient-based; 98.1% implant-based) were reported. In addition, a limited incidence of biologic (4.8% patient-based; 3.8% implant-based) and prosthetic (9.7% patient-based; 7.6% implant-based) complications was reported. The overall 4-year PIMBL amounted to 0.38 ± 0.21 mm (healed ridges 0.4 ± 0.21 mm; fresh post-extraction sockets 0.33 ± 0.20 mm). Conclusions: Loading single implants immediately seems to be a highly successful treatment procedure. However, long-term data are needed to confirm these positive outcomes

Grapevine DMR6-1 Is a candidate gene for susceptibility to Downy mildew

Grapevine (Vitis vinifera) is a valuable crop in Europe for both economical and cultural reasons, but highly susceptible to Downy mildew (DM). The generation of resistant vines is of critical importance for a sustainable viticulture and can be achieved either by introgression of resistance genes in susceptible varieties or by mutation of Susceptibility (S) genes, e.g., by gene editing. This second approach offers several advantages: it maintains the genetic identity of cultivars otherwise disrupted by crossing and generally results in a broad-spectrum and durable resistance, but it is hindered by the poor knowledge about S genes in grapevines. Candidate S genes are Downy mildew Resistance 6 (DMR6) and DMR6-Like Oxygenases (DLOs), whose mutations confer resistance to DM in Arabidopsis. In this work, we show that grapevine VviDMR6-1 complements the Arabidopsis dmr6-1 resistant mutant. We studied the expression of grapevine VviDMR6 and VviDLO genes in different organs and in response to the DM causative agent Plasmopara viticola. Through an automated evaluation of causal relationships among genes, we show that VviDMR6-1, VviDMR6-2, and VviDLO1 group into different co-regulatory networks, suggesting distinct functions, and that mostly VviDMR6-1 is connected with pathogenesis-responsive genes. Therefore, VviDMR6-1 represents a good candidate to produce resistant cultivars with a gene-editing approac

Transcriptomic responses of a simplified soil microcosm to a plant pathogen and its biocontrol agent reveal a complex reaction to harsh habitat

Additional file 1: Concentration of the soil microorganism in the simplified soil microcosm.Additional file 2: Primer sequences of the microcosm genes analysed by real-time RT-PCR.Additional file 3: RNA-Seq sequencing and mapping results for each replicate.Additional file 4: Distribution of read pair alignments to the genomes of the soil microorganisms. (A, B) Distribution of read pair alignments to the 13 soil microorganisms calculated with the Samtools software [30] and expressed as a percentage (%) of total alignments to the microcosm genome. (C, D) Distribution of unique read pairs mapping to genes of the 13 soil microorganisms, counted using HTSeq [32] and expressed as a percentage (%) of total unique read pairs mapping to genes in the microcosm genome. (E, F) Percentage (%) of expressed genes (more than one read pair) calculated as compared to the total predicted genes for each soil microorganism. Mean and standard error values of three replicates are reported for each condition: the simplified soil microcosm collected at the beginning of the experiment (SSM0) and 24 h after incubation either without exogenous fungi (SSM), with the biocontrol agent Trichoderma atroviride (SSM+T), with the plant pathogen Armillaria mellea (SSM+A) or with both (SSM+T+A).Additional file 5: Expression levels of genes of the simplified soil microcosm.Additional file 6: Pearson’s correlation coefficients among replicates and conditions for RNA-Seq analysis.Additional file 7: Clustering and functional annotation results of differentially expressed genes.Additional file 8: Proportion of expressed and differentially expressed genes for each soil microorganism.Additional file 9: Distribution of differentially expressed genes of each soil microorganism in 18 clusters, based on the expression profiles.Additional file 10: Metabolic pathways of the simplified soil microcosm, modulated by incubation in the soil matrix. Metabolic pathways deactivated (left panels) and activated (right panels) by 24 h incubation in the soil matrix (A) without reinforced modulation (cluster 1) and (B) with reinforced modulation (cluster 15) in the presence of Armillaria mellea and Trichoderma atroviride combined. Metabolic pathways modulated by the introduction of (C) T. atroviride (cluster 3), (D) A. mellea (cluster 5), or (E) both (cluster 7). KEGG pathways were visualised using the iPath2 tool [48], the pathways of upregulated (green) and downregulated (red) genes were highlighted, and a section of the most relevant pathways is reported for each panel.Additional file 11: Biological networks of Gene Ontology (GO) terms. GO biological process terms of the simplified soil microcosm, upregulated by incubation in the soil matrix with similar expression profiles in the presence or absence of Armillaria mellea and Trichoderma atroviride (cluster 1). Significantly enriched GO terms (P < 0.001) were identified using the BiNGO tool [42] and visualised with Cytoscape software [43]. The colour scale legend indicates the level of significance for enriched GO terms. White nodes indicate not significantly overrepresented categories.Additional file 12: Key differentially expressed genes discussed in the manuscript, based on their functional categories and expression profiles. Each sheet contains the genes in each cluster discussed.BACKGROUND : Soil microorganisms are key determinants of soil fertility and plant health. Soil phytopathogenic fungi are one of the most important causes of crop losses worldwide. Microbial biocontrol agents have been extensively studied as alternatives for controlling phytopathogenic soil microorganisms, but molecular interactions between them have mainly been characterised in dual cultures, without taking into account the soil microbial community. We used an RNA sequencing approach to elucidate the molecular interplay of a soil microbial community in response to a plant pathogen and its biocontrol agent, in order to examine the molecular patterns activated by the microorganisms. RESULTS : A simplified soil microcosm containing 11 soil microorganisms was incubated with a plant root pathogen (Armillaria mellea) and its biocontrol agent (Trichoderma atroviride) for 24 h under controlled conditions. More than 46 million paired-end reads were obtained for each replicate and 28,309 differentially expressed genes were identified in total. Pathway analysis revealed complex adaptations of soil microorganisms to the harsh conditions of the soil matrix and to reciprocal microbial competition/cooperation relationships. Both the phytopathogen and its biocontrol agent were specifically recognised by the simplified soil microcosm: defence reaction mechanisms and neutral adaptation processes were activated in response to competitive (T. atroviride) or non-competitive (A. mellea) microorganisms, respectively. Moreover, activation of resistance mechanisms dominated in the simplified soil microcosm in the presence of both A. mellea and T. atroviride. Biocontrol processes of T. atroviride were already activated during incubation in the simplified soil microcosm, possibly to occupy niches in a competitive ecosystem, and they were not further enhanced by the introduction of A. mellea. CONCLUSIONS : This work represents an additional step towards understanding molecular interactions between plant pathogens and biocontrol agents within a soil ecosystem. Global transcriptional analysis of the simplified soil microcosm revealed complex metabolic adaptation in the soil environment and specific responses to antagonistic or neutral intruders.The European Union’s Seventh Framework Programme under grant agreement: 324416 (project INNOVA, subprogramme: FP7-PEOPLE-2012-IAPP).http://www.biomedcentral.com/bmcgenomicsam2016Genetic

A 14-Year Follow-Up Study of Sequelae in Primary Teeth and Permanent Successors After Dental Trauma

Objective:&nbsp;To evaluate the presence of sequelae in primary teeth and their permanent successors, as well as associations between TDI and the presence of sequelae in both teeth. Material and Methods: In this 14-year retrospective study, 2.290 records were reviewed, 192 patients who suffered dental trauma in primary teeth were followed until the eruption of successor teeth were included. Descriptive, chi-square, and regression logistic with generalized estimating equations tests were performed (p&lt;0.05). Results: 362 primary and successor teeth were followed. Sequelae were present in 71.8% of primary teeth and 25.7% of their successors. Teeth with complicated fracture (100%), extrusion (100%) and avulsion (100%) resulted in the largest amounts of sequelae in primary teeth and intrusion (61%) on their successors. Age was associated with sequelae in permanent teeth (p&lt;0.01). Extrusion (OR 10.06; CI 2.12-47.63) and intrusion (OR 7.51; CI 2.73-20.70) had a higher risk to cause sequelae in primary and permanent teeth, respectively. Conclusion: The type of injury involved influenced the sequelae in traumatized teeth and their successors, and the age of the child influenced the presence of sequelae in permanent teeth.&nbsp