Calculating the local-type fNL for slow-roll inflation with a non-vacuum initial state

Single-field slow-roll inflation with a non-vacuum initial state has an enhanced bispectrum in the local limit. We numerically calculate the local-type fNL signal in the CMB that would be measured for such models (including the full transfer function and 2D projection). The nature of the result depends on several parameters, including the occupation number N_k, the phase angle \theta_k between the Bogoliubov parameters, and the slow-roll parameter \epsilon. In the most conservative case, where one takes \theta_k \approx \eta_0 k (justified by physical reasons discussed within) and \epsilon\lesssim 0.01, we find that 0 < fNL < 1.52 (\epsilon/0.01), which is likely too small to be detected in the CMB. However, if one is willing to allow a constant value for the phase angle \theta_k and N_k=O(1), fNL can be much larger and/or negative (depending on the choice of \theta_k), e.g. fNL \approx 28 (\epsilon/0.01) or -6.4 (\epsilon/0.01); depending on \epsilon, these scenarios could be detected by Planck or a future satellite. While we show that these results are not actually a violation of the single-field consistency relation, they do produce a value for fNL that is considerably larger than that usually predicted from single-field inflation.Comment: 8 pages, 1 figure. v2: Version accepted for publication in PRD. Added greatly expanded discussion of the phase angle \theta_k; this allows the possibility of enhanced fNL, as mentioned in abstract. More explicit comparisons with earlier wor

Mediterranean diet, physical activity and gut microbiome composition: A cross-sectional study among healthy young italian adults

Background. This cross-sectional study aimed to explore the microbial composition of the gut and its possible association with the Mediterranean diet (MD) after adjusting for demographic and anthropometric characteristics in a sample of healthy young Italian adults. Methods. Gut microbiota, demographic information, and data on adherence to MD and physical activity (PA) habits were collected in a sample of 140 university students (48.6% males, mean age 22.5 ± 2.9) with a mean body mass index (BMI) of 22.4 ± 2.8 kg/m2 (15.2–33.8) and a mean PA level of 3006.2 ± 2973.6 metabolic equivalent (MET)-minutes/week (148–21,090). Results. A high prevalence of Firmicutes and Bacteroidetes was found in all the fecal samples. Significant dissimilarities in the microbiota composition were found on the basis of MD adherence and PA levels (p = 0.001). At the genus level, Streptococcus and Dorea were highly abundant in overweight/obese individuals, Ruminococcus and Oscillospira in participants with lower adherence to MD, and Lachnobacterium in subjects with low levels of PA (p = 0.001). A significantly higher abundance of Paraprevotella was shown by individuals with lower BMI, lower MD adherence, and lower PA levels (p = 0.001). Conclusions. This study contributes to the characterization of the gut microbiome of healthy humans. The findings suggest the role of diet and PA in determining gut microbiota variability

Environmental microbial contamination in dental setting: a local experience

ntroduction. Patients and operators are exposed during dental practice to an infective risk, which derives especially from micro- organisms suspended in aerosols. Environmental microbiologi- cal monitoring in dental settings represents a good instrument to detect critical situations. Methods. In order to investigate environmental microbial contami- nation level in a local reality, we analyzed water, air and surfaces samples of a community-based dental facility by using protocol and threshold values proposed in a recent multicenter study carried out by the Italian Society of Hygiene, Preventive Medicine and Public Health (S.It.I.) working group ?Hygiene in Dentistry?. Microbial contamination was assessed in the same room for 4 non-consecu- tive weeks during all the five working days, before and at the end of the daily activity. Air was sampled also during clinical activity, through both active and passive sampling systems. Results. Contamination of water showed a decrease during activ- ities, while a decrease in air contamination was registered only at the end of the day. Passive sampling values resulted more often above threshold values adopted. At the same time, surfaces con- tamination increases at the end of the activity. It seems that in the dental clinic analyzed microbial buildup represents the higher critical element. No differences have been registered among the different days of the week. Discussion. Our study highlights the need to improve disinfection procedures and air treatment systems in the considered environ- ment. Microbiological monitoring could represent an important element to detect the presence of risk factors and to adopt control measures

The pulsed electron deposition technique for biomedical applications: A review

The "pulsed electron deposition" (PED) technique, in which a solid target material is ablated by a fast, high-energy electron beam, was initially developed two decades ago for the deposition of thin films of metal oxides for photovoltaics, spintronics, memories, and superconductivity, and dielectric polymer layers. Recently, PED has been proposed for use in the biomedical field for the fabrication of hard and soft coatings. The first biomedical application was the deposition of low wear zirconium oxide coatings on the bearing components in total joint replacement. Since then, several works have reported the manufacturing and characterization of coatings of hydroxyapatite, calcium phosphate substituted (CaP), biogenic CaP, bioglass, and antibacterial coatings on both hard (metallic or ceramic) and soft (plastic or elastomeric) substrates. Due to the growing interest in PED, the current maturity of the technology and the low cost compared to other commonly used physical vapor deposition techniques, the purpose of this work was to review the principles of operation, the main applications, and the future perspectives of PED technology in medicine

A deep learning approach for detecting security attacks on blockchain

In these last years, Blockchain technologies have been widely used in several application fields to improve data privacy and trustworthiness and security of systems. Although the blockchain is a powerful tool, it is not immune to cyber attacks: for instance, recently (January 2019) a successful 51% attack on Ethereum Classic has revealed security vulnerabilities of its platform. Under a statistical perspective, attacks can be seen as an anomalous observation, with a strong deviation from the regular behavior. Machine Learning is a science whose goal is to learn insights, patterns and outliers within large data repositories; hence, it can be exploit for blockchain attack detection. In this work, we define an anomaly detection system based on a encoder-decoder deep learning model, that is trained exploiting aggregate information extracted by monitoring blockchain activities. Experiments on complete historical logs of Ethereum Classic network prove the capability of the our model to effectively detect the publicly reported attacks. To the best of our knowledge, our approach is the first one that provides a comprehensive and feasible solution to monitor the security of blockchain transactions

Neural Surface Antibodies and Neurodegeneration: Clinical Commonalities and Pathophysiological Relationships

Autoimmune encephalitis and neurodegenerative disorders share several clinical features, including behavioural and psychiatric manifestations, cognitive impairment, sleep and movement disorders. Therefore, it is not surprising that autoimmune encephalitis is one of the main differential diagnoses of rapidly progressive dementia. However, more chronic presentations of autoimmune disorders have been reported and can lead to the misdiagnosis of a neurodegenerative disease. On the other hand, antibodies against neuronal proteins, such as those directed against NMDAR, can occur during established neurogenerative disorders, and their role in this context is still unclear. They might be simple bystanders or modify the disease course and phenotype. Indeed, autoimmune encephalitis can leave long-term cognitive sequelae and specific antibodies to neuronal surface antigens are associated with clinical and pathological neurodegenerative features. Here we review the link between these antibodies and neurodegeneration. In particular we discuss: (a) the possibility that autoimmune encephalitis presents as a neurodegenerative disease, identifying the red flags that can help in the differential diagnosis between antibody-mediated and neurodegenerative disorders; (b) the occurrence of antibodies against neuronal surface antigens in patients with neurodegenerative disorders and their possible role in the disease course; and (c) the long-term cognitive and neuroradiological changes associated with autoimmune encephalitis, as well as the biomarkers that can help to predict the cognitive outcome. Finally, we review the clinical and pathological features of IgLON5 antibodies-related encephalitis, a unique model of the relationship between antibodies and neurodegeneration

Observational constraints on patch inflation in noncommutative spacetime

We study constraints on a number of patch inflationary models in noncommutative spacetime using a compilation of recent high-precision observational data. In particular, the four-dimensional General Relativistic (GR) case, the Randall-Sundrum (RS) and Gauss-Bonnet (GB) braneworld scenarios are investigated by extending previous commutative analyses to the infrared limit of a maximally symmetric realization of the stringy uncertainty principle. The effect of spacetime noncommutativity modifies the standard consistency relation between the tensor spectral index and the tensor-to-scalar ratio. We perform likelihood analyses in terms of inflationary observables using new consistency relations and confront them with large-field inflationary models with potential V \propto \vp^p in two classes of noncommutative scenarios. We find a number of interesting results: (i) the quartic potential (p=4) is rescued from marginal rejection in the class 2 GR case, and (ii) steep inflation driven by an exponential potential (p \to \infty) is allowed in the class 1 RS case. Spacetime noncommutativity can lead to blue-tilted scalar and tensor spectra even for monomial potentials, thus opening up a possibility to explain the loss of power observed in the cosmic microwave background anisotropies. We also explore patch inflation with a Dirac-Born-Infeld tachyon field and explicitly show that the associated likelihood analysis is equivalent to the one in the ordinary scalar field case by using horizon-flow parameters. It turns out that tachyon inflation is compatible with observations in all patch cosmologies even for large p.Comment: 16 pages, 11 figures; v2: updated references, minor corrections to match the Phys. Rev. D versio

Gauge-Invariant Quasi-Free States on the Algebra of the Anyon Commutation Relations

Let $X=\mathbb R^2$ and let $q\in\mathbb C$, $|q|=1$. For $x=(x^1,x^2)$ and $y=(y^1,y^2)$ from $X^2$, we define a function $Q(x,y)$ to be equal to $q$ if $x^1y^1$, and to $\Re q$ if $x^1=y^1$. Let $\partial_x^+$, $\partial_x^-$ ($x\in X$) be operator-valued distributions such that $\partial_x^+$ is the adjoint of $\partial_x^-$. We say that $\partial_x^+$, $\partial_x^-$ satisfy the anyon commutation relations (ACR) if $\partial^+_x\partial_y^+=Q(y,x)\partial_y^+\partial_x^+$ for $x\ne y$ and $\partial^-_x\partial_y^+=\delta(x-y)+Q(x,y)\partial_y^+\partial^-_x$ for $(x,y)\in X^2$. In particular, for $q=1$, the ACR become the canonical commutation relations and for $q=-1$, the ACR become the canonical anticommutation relations. We define the ACR algebra as the algebra generated by operator-valued integrals of $\partial_x^+$, $\partial_x^-$. We construct a class of gauge-invariant quasi-free states on the ACR algebra. Each state from this class is completely determined by a positive self-adjoint operator $T$ on the real space $L^2(X,dx)$ which commutes with any operator of multiplication by a bounded function $\psi(x^1)$. In the case $\Re q0$), we discuss the corresponding particle density $\rho(x):=\partial_x^+\partial_x^-$. For $\Re q\in(0,1]$, using a renormalization, we rigorously define a vacuum state on the commutative algebra generated by operator-valued integrals of $\rho(x)$. This state is given by a negative binomial point process. A scaling limit of these states as $\kappa\to\infty$ gives the gamma random measure, depending on parameter $\Re q$