Three-dimensional Topological Insulators and Bosonization

Massless excitations at the surface of three-dimensional time-reversal invariant topological insulators possess both fermionic and bosonic descriptions, originating from band theory and hydrodynamic BF gauge theory, respectively. We analyze the corresponding field theories of the Dirac fermion and compactified boson and compute their partition functions on the three-dimensional torus geometry. We then find some non-dynamic exact properties of bosonization in (2+1) dimensions, regarding fermion parity and spin sectors. Using these results, we extend the Fu-Kane-Mele stability argument to fractional topological insulators in three dimensions.Comment: 54 pages, 11 figure

Experimental analysis of masonry ring beams reinforced with composite materials

It is known that the application of a ring beam is an effective method to prevent an out-of-plane collapse mechanism of perimeter wall panels. However this effective reinforcing method presents some problems. In order to address this, this paper describes the problems associated with this reinforcing method and studies a new technique for reinforcing historic masonry buildings by realizing a new type of ring beam made of recycled old stones or bricks reinforced at the bed joints with glass-fibre sheets, GFRP (Glass Fiber Reinforced Polymer) grids or/and PBO (polybenzoxazole: poly-p-phenylene benzobisoxazole) cords. An experimental investigation has been carried out on 8 full-scale rubble-stone or brickwork masonry ring beams tested in bending. The testing included the use of composite materials inserted into the mortar joints during the fabrication phase of the beams and pinned end conditions (four-point bending configuration). Beams were reinforced with different reinforcement layout

Embryo disposal practices in IVF clinics in the United States

BACKGROUND. The moral status of the human embryo is particularly controversial in the United States, where one debate has centered on embryos created in excess at in vitro fertilization (IVF) clinics. Little has been known about the disposal of these embryos. METHODS.We mailed anonymous, self-administered questionnaires to directors of 341 American IVF clinics. RESULTS. 217 of 341 clinics (64 percent) responded. Nearly all (97 percent) were willing to create and cryopreserve extra embryos. Fewer, but still a majority (59 percent), were explicitly willing to avoid creating extras. When embryos did remain in excess, clinics offered various options: continual cryopreservation for a charge (96 percent) or for no charge (4 percent), donation for reproductive use by other couples (76 percent), disposal prior to (60 percent) or following (54 percent) cryopreservation, and donation for research (60 percent) or embryologist training (19 percent). Qualifications varied widely among those personnel responsible for securing couples’ consent for disposal and for conducting disposal itself. Some clinics performed a religious or quasi-religious disposal ceremony. Some clinics required a couple’s participation in disposal; some allowed but did not require it; some others discouraged or disallowed it. CONCLUSIONS. The disposal of human embryos created in excess at American IVF clinics varies in ways suggesting both moral sensitivity and ethical divergence

Emotional Difficulties in Adolescence: Psychopathology and Family Interactions.

Introduction. Several studies on developmental age have investigated aspects relating to emotional competence, and alexithymia in particular, showing that it is associated with behavioral problems in childhood and adolescence. Some such research has focused on the relationship between emotional difficulties and family interactions assuming a link between the quality of family relationships and a child\u2019s emotional competence. Subjects and Methods. The aims of the present study were: 1) to compare a group of psychiatric adolescents with a group of \u201chealthy\u201d adolescents in terms of any alexithymia and its relationship with the former\u2019s psychopathological issues; 2) to clarify the relationship, if any, between psychopathology, alexithymia and family interaction patterns in our sample of psychiatric adolescents. The experimental group consisted of 41 psychiatric adolescents and the control group of 41 students matched for gender and age. The Toronto Alexithymia Scale (TAS-20) was used to identify any alexithymic traits, the Youth Self Report (YSR) 11-18 and the CBCL to detect any psycho-behavioral problems, and the Lausanne Trilogue Play (LTP) to analyze family interactions. Results. There was a higher prevalence of alexithymia among the adolescents with mental health problems than in the control group, and a correlation between their scores for internalizing problems and alexithymia. In the experimental group, adolescents with internalizing problems, somatic complaints and attention difficulties belonged to families revealing high levels of parental conflict. As for alexithymia, adolescents\u2019 difficulty identifying emotions correlated significantly with the same trait in their mothers. This feature also seemed to be associated with better family interactions. Conclusion. Our study confirms the importance of family relationships in the development of emotional skills, and highlights how deficiencies in the development of emotional competence are strongly associated with psychopathologies in adolescence. In the light of these findings, it is advisable in clinical practice to provide psychotherapeutic interventions for teens and their parents

Madelung's Disease

Description of a case of Madelung diseas

A new model with Serpent for the first criticality benchmarks of the TRIGA Mark II reactor

We present a new model, developed with the Serpent Monte Carlo code, for neutronics simulation of the TRIGA Mark II reactor of Pavia (Italy). The complete 3D geometry of the reactor core is implemented with high accuracy and detail, exploiting all the available information about geometry and materials. The Serpent model of the reactor is validated in the fresh fuel configuration, through a benchmark analysis of the first criticality experiments and control rods calibrations. The accuracy of simulations in reproducing the reactivity difference between the low power (10 W) and full power (250 kW) reactor condition is also tested. Finally, a direct comparison between Serpent and MCNP simulations of the same reactor configurations is presented

Ischemic Damage of the Flaps: New Treatments.

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An investigation on the possible use of coffee silverskin in PLA/PBS composites

The production of degradable packaging materials is a task that can be no lon-ger postponed. Moreover, high amounts of agricultural wastes are landfilledwithout any recycling. In this research, the possibility to formulate particulatecomposites made of biopolymers filled with coffee waste with acceptable physi-cal and mechanical characteristics that will degrade is investigated. The addi-tion of this agricultural waste, by reducing the requested amount ofbiopolymer, can decrease the overall price of the material presently the mainlimiting factor to the use of biopolymers in the packaging industry. Silverskin,the integument of coffee beans discarded during the roasting process, after amilling step, is added up to a 30 wt% either to polylactic acid (PLA) or to ablend of PLA and polybutylene succinate. The filler can be homogeneously dis-persed in both systems. The data shows that the silverskin filler increases theelastic modulus but decreases the tensile strength of the material and helps thedevelopment of crystal phase in the matrix. The thermal stability and thehydrophobicity of the materials stay almost unchanged on filler addition.Moreover, data shows that the addition of silverskin increases the materialssusceptibility to microbial attack

Molecular epidemiology and pathogenic potential of underdiagnosed human papillomavirus types

<p>Abstract</p> <p>Background</p> <p>Human papillomavirus (HPV) tests are crucial diagnostic tools for the prevention of neoplastic lesions of the uterine cervix. However most commercial methods are designed to detect high-risk (HR) HPV types and a limited selection of low-risk ones, thus missing a fair number of intermediate/low-risk types. As a result, many HPV infections remain undiagnosed, generating distrust in virological diagnosis among gynaecologists, who continue to rely preferentially on cytological and colposcopic findings.</p> <p>Results</p> <p>In this study, we tested 6,335 consecutive clinical samples, most of them from Italian patients with cytological abnormalities. The samples, collected in 2000–2007, were analyzed using PCR amplification of a 173–206 bp (depending on HPV type) conserved region in the L1 open reading frame, restriction endonuclease analysis and, where required, sequence analysis for type determination. Analysis of a smaller male sample and long term follow-up of a few female subjects was also performed. A total of 2,161 samples tested positive for HPV DNA (32.1%); 21.3% of them were mixed infections. Overall, 59 known and 2 unknown HPV types were detected. Their relative prevalence was calculated; notably, types not clearly identifiable using the most common commercial method accounted for 36% of infections. Clinical findings associated with the underdiagnosed types ranged from H-SIL to low-grade abnormalities, although none of these infections resulted in invasive cancer.</p> <p>Conclusion</p> <p>Given the high prevalence of some underdiagnosed HPV types in the population (principally HPV53, HPV66, HPV84, and HPV87) and their frequent association with cytological abnormalities, techniques capable of detecting and typing them would prove extremely useful.</p