The observation of π-shifts in the Little-Parks effect in 4Hb-TaS2.

Finding evidence of non-trivial pairing states is one of the greatest experimental challenges in the field of unconventional superconductivity. Such evidence requires phase-sensitive probes susceptible to the internal structure of the order parameter. We report the measurement of the Little-Parks effect in the unconventional superconductor candidate 4Hb-TaS2. In half of our rings, which are fabricated from single-crystals, we find a π-shift in the transition-temperature oscillations. According to theory, such a π-shift is only possible if the order parameter is non-s-wave. In the absence of crystallographic defects, the shift provides evidence of a multi-component order parameter. Thus, this observation increases the likelihood of the two-component order parameter scenario in 4Hb-TaS2. Furthermore, we show that Tc is enhanced as a function of the out-of-plane field when a constant in-plane field is applied, which we explain using a two-component order-parameter.

Mode coupling bi-stability and spectral broadening in buckled carbon nanotube mechanical resonators.

Bi-stable mechanical resonators play a significant role in various applications, such as sensors, memory elements, quantum computing and mechanical parametric amplification. While carbon nanotube based resonators have been widely investigated as promising NEMS devices, a bi-stable carbon nanotube resonator has never been demonstrated. Here, we report a class of carbon nanotube resonators in which the nanotube is buckled upward. We show that a small upward buckling yields record electrical frequency tunability, whereas larger buckling can achieve Euler-Bernoulli bi-stability, the smallest mechanical resonator with two stable configurations to date. We believe that these recently-discovered carbon nanotube devices will open new avenues for realizing nano-sensors, mechanical memory elements and mechanical parametric amplifiers. Furthermore, we present a three-dimensional theoretical analysis revealing significant nonlinear coupling between the in-plane and out-of-plane static and dynamic modes of motion, and a unique three-dimensional Euler-Bernoulli snap-through transition. We utilize this coupling to provide a conclusive explanation for the low quality factor in carbon nanotube resonators at room temperature, key in understanding dissipation mechanisms at the nano scale.

DC Signature of Snap-through Bistability in Carbon Nanotube Mechanical Resonators.

Bistable arched beams exhibiting Euler-Bernoulli snap-through buckling are widely investigated as promising candidates for various potential applications, such as memory devices, energy harvesters, sensors, and actuators. Recently, we reported the realization of a buckled suspended carbon nanotube (CNT) based bistable resonator, which exhibits a unique three-dimensional snap-through transition and an extremely large change in frequency as a result. In this article, we address a unique characteristic of these devices in which a significant change in the DC conductance is also observed at the mechanical snap-through transition. Through the analysis of this phenomenon, we arrive at several important conclusions: we find that the common approach to determining CNT vibrational resonance amplitude is inaccurate; we find evidence that latching phenomena should be easily realizable, relevant for RF switches and nonvolatile memory devices. Finally, we present evidence for possible inner shell sliding, which is relevant for understanding interlayer coupling and moiré pattern research.

Effect of dielectric constant tuning on a photonic cavity frequency and Q-factor.

For practical applications in quantum electrodynamics, it has been proposed to produce frequency tuning or Q-switching by dynamically changing the dielectric constant around a nano-cavity. Local changes in the dielectric constant of a photonic cavity with finite-lifetime, may affect not only the frequency of electromagnetic cavity modes but also their quality-factor (Q). Thus, it is important to have prediction capability regarding the combined effect of these changes. Here perturbation theory, usually applied to eigenmodes with real eigenvalues, is formulated in the complex domain, in which the eigen-frequency imaginary part is related to the Q-factor. Normalizable leaky modes, and bi-orthogonality in a finite volume are the basis for such a formulation. We introduce such capabilities by presenting semi-analytical expressions of first order perturbation analysis for a 3D cavity with radiation losses. The obtained results are in good agreement with numerical calculations.

[Multisensory environmental intervention (snoezelen) as a preventive alternative to seclusion and restraint in closed psychiatric wards].

UNLABELLED: Seclusion and restraint, unfortunately, still remain a routine practice in closed psychiatric wards worldwide and in Israel. These practices often lead to distress, traumatized patients, and further increase the negative view and stigmatization of psychiatric treatment and, most especially, psychiatric hospitalization. Multisensory environmental intervention, Snoezelen, combines sensory integration theory with a client-oriented approach. Snoezelen treatment calms and relaxes agitative patients giving them a feeling of dignity, initiative and freedom of choice. The Snoezelen room is a high-tech, multisensory environment that includes music, light of fiber optic strands, calming image projections, vibrations of bubbles tubes, and soothing smells. After 30 to 40 minutes of exposure to Snoezelen, agitative patients in our closed ward reported substantial reduction of their distress level and, outwardly, appeared less agitated and displayed less aggressive and hostile behavior. Foremost, since the beginning of the multisensory environmental interventions in the closed wards, a statistically significant reduction in the number of restraints and seclusions has occurred in the closed male section in comparison to the closed female section, where snoezelen has not been administered (P < 0.05). IN CONCLUSION: Snoezelen is an innovative and preventative alternative to seclusion and restraint in closed psychiatric settings. It produces a calming effect on agitative patients, reduces the length of time and number of seclusions and restraints, and diminishes the stigma against psychiatric treatment and hospitalization.

[Legal involvement in psychiatric care].

In an amendment to the law regarding the treatment of the Mental Health patient in 1991, authority was given to the regional psychiatrists' committee to oversee compulsory orders for psychiatric hospitalization and compulsory orders for outpatient psychiatric treatment--and the extension of these orders. On 1st of June 2002 a pilot study was started in the Jerusalem region, in which mental health patients were to be represented by lawyers employed by the Ministry of Justice. The pilot study began as an initiative of the Ministry of Justice, in agreement with the Ministry of Health. We describe 3 cases which demonstrate that the procedure of legal representation lacks the necessary balance between medical and legal considerations. The decision of the regional psychiatrists' committee or the court is liable to worsen the patients' mental health status and even to accelerate aggression towards self or others. In rare cases a premature discharge based on legal considerations rather than medical evaluation may result in suicide, as demonstrated in one of the vignettes. The article discusses the unbalanced approach of legal versus medical consideration, preference of "liberty" over health and the "wish" of the patient rather than his well-being. The article considers the unbalanced approach of the legal system to appeals of therapists against the decision of the regional psychiatrists' committee, where prosecutors of the state decided an appeal of this kind over the staff treating the patient has no precedence. That was presented as justification that it should be rejected. A pilot study compared between patients discharged from compulsory hospitalization through regional psychiatrists' committee or court and patients discharged on a medical basis without legal interference. The study showed a shorter stay in the community in the first group (42%) compared to 75% stay in the community in the second group, after six months. We are of the opinion that the current provision of legal assistance is lacking the necessary balance between medical and legal considerations; the 'wish for freedom' as a default, although illogical, is within the new system of legal aid, and is more considerate and important than the 'best interests' of the patient and his health.

Comparison between two legal indications for compulsory outpatient treatment in Israel.

The aim of the present study was to compare the outcome of two legal indications for Compulsory Outpatient Treatment (COT) in Israel (a) as an alternative to compulsory hospitalization (CH) and (b) as a follow-up to CH. Demographic, clinical and legal measurements based on 326 COT orders issued in the Jerusalem and Southern district of Israel were compared according to the two legal provisions for COT contained in the Treatment of Mental Patients Law (1991). The COT order was found to be more effective when used as an alternative to CH (53.1%) than when it was used following CH (38.8%), p = 0.002. In the former case, there were fewer schizophrenic patients, fewer hospitalizations, fewer visits to psychiatric emergency services and longer remissions. Our results point to the influence of the legal indications on the efficacy of the COT order and help define the target population.