Effective Hamiltonian with holomorphic variables

The pure-quantum self-consistent harmonic approximation (PQSCHA) permits to study a quantum system by means of an effective classical Hamiltonian - depending on quantum coupling and temperature - and classical-like expressions for the averages of observables. In this work the PQSCHA is derived in terms of the holomorphic variables connected to a set of bosonic operators. The holomorphic formulation, based on the path integral for the Weyl symbol of the density matrix, makes it possible to approach directly general Hamiltonians given in terms of bosonic creation and annihilation operators.Comment: 11 pages, no figures (2nd version: few mistakes fixed in Sects. IV-V

Effective Hamiltonian with holomorphic variables

The pure-quantum self-consistent harmonic approximation (PQSCHA) permits to study a quantum system by means of an effective classical Hamiltonian. In this work the PQSCHA is reformulated in terms of the holomorphic variables connected to a set of bosonic operators. The holomorphic formulation, based on the olomorphic path integral for the Weyl symbol of the density matrix, makes it possible to directly approach general Hamiltonians given in terms of bosonic creation and annihilation operators.Comment: Proceedings of the Conference "Path Integrals from peV to TeV - 50 Years from Feynman's paper" (Florence, August 1998) -- 2 pages, ReVTe

The importance of the postmortem interval for the diagnosis of Waterhouse–Friderichsen syndrome by Neisseria meningitidis in a series of forensic cases

The effective value of microbiological post-mortem examinations stands as fundamental in forensic cases involving microbiology. We ran these analyses on five victims, who suddenly died after showing persistent fever. The examinations were conducted between 48 hours and 10 days after death, and adrenal gland apoplexy was detected in all the cases. Microbiological examinations identified Neisseria meningitidis, which was accountable for Waterhouse–Friderichsen syndrome. Diplococci were isolated from three cadavers that underwent forensic dissection between 2 and 3 days after death. The remaining two cadavers showed polymicrobial contamination, and a polymerase chain reaction technique was necessary to identify the pathogen. We assumed that the microbial overlap could lead to diagnostic mistakes and conceal the identification of the lethal pathogen. Therefore, we suggest using molecular techniques for a postmortem interval (PMI) longer than 72 hours. Classical microbiological examination should be performed for PMI within 72 hours

The importance of the postmortem interval for the diagnosis of Waterhouse-Friderichsen syndrome by Neisseria meningitidis in a series of forensic cases

The effective value of microbiological post-mortem examinations stands as fundamental in forensic cases involving microbiology. We ran these analyses on five victims, who suddenly died after showing persistent fever. The examinations were conducted between 48 hours and 10 days after death, and adrenal gland apoplexy was detected in all the cases. Microbiological examinations identified Neisseria meningitidis, which was accountable for Waterhouse-Friderichsen syndrome. Diplococci were isolated from three cadavers that underwent forensic dissection between 2 and 3 days after death. The remaining two cadavers showed polymicrobial contamination, and a polymerase chain reaction technique was necessary to identify the pathogen. We assumed that the microbial overlap could lead to diagnostic mistakes and conceal the identification of the lethal pathogen. Therefore, we suggest using molecular techniques for a postmortem interval (PMI) longer than 72 hours. Classical microbiological examination should be performed for PMI within 72 hours

Effective classical Hamiltonian for the statistical mechanics of bosonic and fermionic systems

Dottorato di ricerca in fisica. 12. ciclo. Supervisore Ruggero VaiaConsiglio Nazionale delle Ricerche - Biblioteca Centrale - P.le Aldo Moro, 7, Rome; Biblioteca Nazionale Centrale - P.za Cavalleggeri, 1, Florence / CNR - Consiglio Nazionale delle RichercheSIGLEITItal

Observations on self-incineration characteristics in 24 years (1993â2016) of autopsies in the city of Milan

Self-incineration is one of the most dramatic and lethal suicide methods. It is rarely reported in Western countries and is more frequent in developing regions. We illustrate the forensic cases of self-immolation occurring over 24 years in the city of Milan, Italy, highlighting the main issues of such a complex and rare suicide. We selected 33 cases of self-incineration among 23,417 autopsies (4022 suicides) performed at the Department of Legal Medicine of the University of Milan over a period of 24 years (1993â2016). Several parameters were included and analysed: gender and age of the victims, pathological history, previous suicide intentions/attempts, duration of burning, place of death or discovery of the corpse, circumstantial data of fatal events and autopsy findings, with particular attention to thermal injuries. Self-incineration was found in 0.8% of total suicides and 0.14% of total autopsies. One of these cases involved a complex modality (association with plastic-bag suffocation). The typical characteristics of the victim were an Italian man with psychiatric illness, frequently moved by passion, existential discomfort and economic problems. During the 24-year period, the number of cases of self-incineration progressively reduced. This study provides a general overview in one of the biggest metropolitan Italian areas and is one of the few works performed on this topic. It may be helpful in understanding and studying such an unusual manner of suicide

Neuroactive steroids and GABAA receptor plasticity in the brain of the WAG/Rij rat, a model of absence epilepsy

The role of neuroactive steroids and GABAA receptors in the generation of spontaneous spike-and-wave discharges (SWDs) was investigated in the WAG/Rij rat model of absence epilepsy. The plasma, cerebrocortical, and thalamic concentrations of the progesterone metabolite 3α-hydroxy-5α-pregnan-20-one (3,5-TH PROG) were increased in the WAG/Rij rat at 2 months of age compared with those in control (Wistar) rats. In contrast, the brain and peripheral levels of 3α,5α-tetrahydrodeoxycorticosterone (3,5-TH DOC) did not differ between the two rat strains at this age. At 6 months of age, when absence epilepsy worsens in WAG/Rij rats, the plasma concentration of 3,5-TH PROG remained high whereas that of 3,5-TH DOC had increased, the cerebrocortical levels of both 3,5-TH PROG and 3,5-TH DOC had increased, and the thalamic concentrations of these metabolites had decreased. At 6 months of age the expression of the α4 and δ subunits of the GABAA receptor in relay nuclei was increased. Finally, chronic stress induced by social isolation elicited a reduction in the amount of 3,5-TH PROG in the thalamus of 2-month-old WAG/Rij rats that was associated with a reduction in the number and overall duration of SWDs at 6 months of age. Absence epilepsy in the WAG/Rij rat is thus associated with changes in the abundance of neuroactive steroids and in the expression of specific GABAA receptor subunits in the thalamus, a brain area key to the pathophysiology of this condition

Parental Social Isolation during Adolescence Alters Gut Microbiome in Rat Male Offspring

Previous work from our laboratory demonstrated that parental stress, induced by social isolation starting at puberty, leads to behavioral, endocrine, and biochemical changes in the male, but not female, offspring (ISO-O) of Sprague-Dawley rats. Here, we report alterations in the gut microbiota composition of ISO-O vs. grouped-housed offspring (GH-O), although all animals received the same diet and were housed in the same conditions. Analysis of bacterial communities by next-generation sequencing (NGS) of 16S rRNA gene revealed alterations at family and order levels within the main phyla of Bacteroides, Proteobacteria, and Firmicutes, including an almost total deficit in Limosilactobacillus reuteri (formerly Lactobacillus reuteri) and a significant increase in Ligilactobacillus murinus (formerly Lactobacillus murinus). In addition, we found an increase in the relative abundance of Rhodospirillales and Clostridiales in the families of Lachnospiraceae and Ruminococcaceae, and Bacteroidales in the family of Prevotellaceae. Furthermore, we examined plasma levels of the proinflammatory cytokines interleukin-1-beta and tumor necrosis factor-alpha, which did not differ between the two groups, while corticosterone concentrations were significantly increased in ISO-O rats. Our findings suggest that adverse environmental conditions experienced by parents may have an impact on the likelihood of disease development in the subsequent generations