A polarisation modulation scheme for measuring vacuum magnetic birefringence with static fields

A novel polarisation modulation scheme for polarimeters based on Fabry-Perot cavities is presented. The application to the proposed HERA-X experiment aiming to measuring the magnetic birefringence of vacuum with the HERA superconducting magnets is discussed

Frequency locking to a high-finesse Fabry-Perot cavity of a Frequency doubled Nd:YAG laser used as the optical phase modulator

We report on the frequency locking of a frequency doubled Nd:YAG laser to a 45 000 finesse, 87-cm-long, Fabry-Perot cavity using a modified form of the Pound-Drever-Hall technique. Necessary signals, such as light phase modulation and frequency correction feedback, are fed direcly to the infrared pump laser. This is sufficient to achieve a stable locking of the 532 nm visible beam to the cavity, also showing that the doubling process does not degrade laser performances.Comment: submitted to Review of Scientific Instrument

A proposal for a brief-term post-adoption intervention in the attachment-perspective. A single case study with a late-adopted child and his adoptive mother

A growing body of attachment literature has focused on bridging the gap between research and clinical applications, even in clinical work with adoptive families. A brief-term clinical intervention focused on a multi-method assessment of attachment relationships and representations was performed in the first year after placement. This single case study aimed at analysing the attachment outcomes, through a long-term follow-up, both for the adoptive mother and her late-adopted son. We assumed that this five-session attachment oriented intervention could help the mother enhance her sensitivity skills and her ability to understand both her own past attachment experiences and her child’s insecure attachment as a consequence of the failures of his previous experiences of care, supporting her six year old child in acquiring a positive image of himself and of others and the security of the caregiver’s availability up to adolescence

Alternative practices of achieving anaesthesia for dental procedures: a review

Managing pain and anxiety in patients has always been an essential part of dentistry. To prevent pain, dentists administer local anaesthesia (LA) via a needle injection. Unfortunately, anxiety and fear that arise prior to and/or during injection remains a barrier for many children and adults from receiving dental treatment. There is a constant search for techniques to alleviate the invasive and painful nature of the needle injection. In recent years, researchers have developed alternative methods which enable dental anaesthesia to be less invasive and more patient-friendly. The aim of this review is to highlight the procedures and devices available which may replace the conventional needle-administered local anaesthesia. The most known alternative methods in providing anaesthesia in dentistry are: topical anaesthesia, electronic dental anaesthesia, jet-injectors, iontophoresis, and computerized control local anaesthesia delivery systems. Even though these procedures are well accepted by patients to date, it is the authors' opinion that the effectiveness practicality of such techniques in general dentistry is not without limitations

Towards a direct measurement of vacuum magnetic birefringence: PVLAS achievements

Nonlinear effects in vacuum have been predicted but never observed yet directly. The PVLAS collaboration has long been working on an apparatus aimed at detecting such effects by measuring vacuum magnetic birefringence. Unfortunately the sensitivity has been affected by unaccounted noise and systematics since the beginning. A new small prototype ellipsometer has been designed and characterized at the Department of Physics of the University of Ferrara, Italy entirely mounted on a single seismically isolated optical bench. With a finesse F = 414000 and a cavity length L = 0.5 m we have reached the predicted sensitivity of psi = 2x10^-8 1/sqrt(Hz) given the laser power at the output of the ellipsomenter of P = 24 mW. This record result demonstrates the feasibility of reaching such sensitivities and opens the way to designing a dedicated apparatus for a first detection of vacuum magnetic birefringence

Experimental observation of optical rotation generated in vacuum by a magnetic field

We report the experimental observation of a light polarization rotation in vacuum in the presence of a transverse magnetic field. Assuming that data distribution is Gaussian, the average measured rotation is (3.9+/-0.5)e-12 rad/pass, at 5 T with 44000 passes through a 1m long magnet, with lambda = 1064 nm. The relevance of this result in terms of the existence of a light, neutral, spin-zero particle is discussed.Comment: 11 pages, 4 figures, submitted to Physical Review Letters Comment to version 2: minor changes to abstract and final discussion. Added 2 references Comment to version 3: corrected minor typographical errors, eliminated the distinction between scalar and pseudoscalar in the particle interpretation of the resul

Bell lysaker emotion recognition test: a contribution for the italian validation

INTRODUCTION: Emotion recognition deficits in psychopathology have been extensively studied with a variety of measures. The Bell Lysaker Emotion Recognition Test (BLERT; Bell et al., 1997) is an effective method to assess emotion recognition by presenting affect stimuli which may have greater verisimilitude with real life events. Indeed, BLERT combines facial expressions with affective information transmitted in prosody or body posture. This method has allowed the study of emotion recognition deficit in psychotic patients, as well as its relationships with other aspects of psychopathology (Vohs et al., 2014). OBJECTIVES: We aimed at testing the validity and reliability of an Italian version of the BLERT. AIMS: First, a group-comparison was carried out between clinical and nonclinical participants. Then, correlations among BLERT scores and other indices of psychological functioning were explored. METHODS: We recruited 12 inpatients with psychotic disorders (mean age= 54.75; 58.3% female) and 45 nonclinical participants (mean age= 24.04; 75.6% female). We administered the BLERT (Bell et al., 1997), along with the following measures: Empathy Quotient (Lawrence et al., 2004), Interpersonal Reactivity Index (Davis, 1980), Difficulties in Emotion Regulation Scale (Gratz & Roemer, 2004), and the Inventory of Interpersonal Problems-47 (Pilkonis et al., 1996). RESULTS: Clinical participants resulted impaired in all indices of the BLERT. Further, the construct validity of the BLERT was confirmed by associations with measures of empathy, emotion dysregulation, and interpersonal problems. CONCLUSIONS: The use of the Italian version of the BLERT seemed promising for the study of emotion recognition in both clinical and nonclinical samples

New PVLAS results and limits on magnetically induced optical rotation and ellipticity in vacuum

IIn 2006 the PVLAS collaboration reported the observation of an optical rotation generated in vacuum by a magnetic field. To further check against possible instrumental artifacts several upgrades to the PVLAS apparatus have been made during the last year. Two data taking runs, at the wavelength of 1064 nm, have been performed in the new configuration with magnetic field strengths of 2.3 T and 5 T. The 2.3 T field value was chosen in order to avoid stray fields. The new observations do not show the presence of a rotation signal down to the levels of $1.2\cdot 10^{-8}$ rad at 5 T and $1.0\cdot 10^{-8}$ rad at 2.3 T (at 95% c.l.) with 45000 passes in the magnetic field zone. In the same conditions no ellipticity signal was detected down to $1.4\cdot 10^{-8}$ at 2.3 T (at 95% c.l.), whereas at 5 T a signal is still present. The physical nature of this ellipticity as due to an effect depending on $B^2$ can be excluded by the measurement at 2.3 T. These new results completely exclude the previously published magnetically induced vacuum dichroism results, indicating that they were instrumental artifacts. These new results therefore also exclude the particle interpretation of the previous PVLAS results as due to a spin zero boson. The background ellipticity at 2.3 T can be used to determine a new limit on the total photon-photon scattering cross section of $\sigma_{\gamma\gamma} < 4.5 \cdot10^{-34}$ barn at 95% c.l..Comment: 25 pages, 7 figures Main changes rel. to v.2: minor changes to abstract, replaced Figures 4,5,6, corrected typographical errors. Paper submitted to Physical Review