Dicke-Cooperativity-Assisted Ultrastrong Coupling Enhancement in Terahertz Metasurfaces.

A system of N two-level atoms cooperatively interacting with a photonic field can be described as a single giant atom coupled to the field with interaction strength ∝N. This enhancement, known as Dicke cooperativity in quantum optics, has recently become an indispensable element in quantum information technology. Here, we extend the coupling beyond the standard light-matter interaction paradigm, enhancing Dicke cooperativity in a terahertz metasurface with N meta-atoms. The cooperative enhancement is manifested through the hybridization of the localized surface plasmon resonance in individual meta-atoms and surface lattice resonance due to the periodic array. Furthermore, through engineering of the capacitive split-gap in the meta-atoms, we were able to enhance the coupling rate into the ultrastrong coupling regime by a factor of N. Our strategy can serve as a new platform for demonstrating effective control of fermionic systems by weak pumping, superradiant emission, and ultrasensitive sensing of molecules.

Magnetic Control of Soft Chiral Phonons in PbTe.

PbTe crystals have a soft transverse optical phonon mode in the terahertz frequency range, which is known to efficiently decay into heat-carrying acoustic phonons, resulting in anomalously low thermal conductivity. Here, we studied this phonon via polarization-dependent terahertz spectroscopy. We observed softening of this mode with decreasing temperature, indicative of incipient ferroelectricity, which we explain through a model including strong anharmonicity with a quartic displacement term. In magnetic fields up to 25 T, the phonon mode splits into two modes with opposite handedness, exhibiting circular dichroism. Their frequencies display Zeeman splitting together with an overall diamagnetic shift with increasing magnetic field. Using a group-theoretical approach, we demonstrate that these observations are the result of magnetic field-induced morphic changes in the crystal symmetries through the Lorentz force exerted on the lattice ions. Thus, our Letter reveals a novel process of controlling phonon properties in a soft ionic lattice by a strong magnetic field.

The influence of persistent bleeding after supracervical hysterectomy on depressive and anxious symptoms: a prospective bicenter study.

PURPOSE: Postoperative spotting is a frequent adverse symptom after laparoscopic supracervical hysterectomy (LSH). The conical excision (eLSH) reduces the postoperative spotting rate, but data in a larger collective are still rare and inconsistent. The influence of persistent bleeding on the anxious and depressive symptoms has not been analyzed yet. METHODS: 311 patients, who underwent a laparoscopic supracervical hysterectomy with conical excision (n = 163), or with straight cervical resection (n = 148) were included. Anxious and depressive symptoms and postoperative spotting were recorded before operation, at 3 month follow-up and at 1 year follow-up in both operative groups using a validated questionnaire (German version of Hospital Anxiety and Depression Scale, HADS-D) and additional questions concerning the frequency and impact of bleeding. Statistical analysis included the impairment of bleeding as well as its impact on depressive and anxious symptoms for both groups. RESULTS: 11.5% after eLSH and 15.5% after LSH reported spotting after 1 year. Supracervical hysterectomy significantly improves depressive and anxious symptoms at 3 and at 12 month follow-up for both groups (p < 0.001) independent on residual spotting. Patients with a preoperative continuous bleeding showed a maximum benefit independent on operative method. CONCLUSION: Laparoscopic supracervical hysterectomy has a positive effect on anxious and depressive symptoms in the short-term and intermediate-term follow-up. The conical excision of the cervical stump reduces postoperative spotting rate, but has no explicit advantage on symptoms of depression or anxiety, irrespective of residual postoperative spotting.

The influence of conventional and extended supracervical hysterectomy on sexuality and quality of life parameters: a prospective bi-center study with a special focus on postoperative spotting.

PURPOSE: Supracervical as well as total hysterectomy are considered to improve postoperative sexuality as well as quality of life, but the benefit of supracervical hysterectomy (LSH) is impaired in up to 20 percent by postoperative spotting. The aim of this study was to analyze the influence of a conical excision of the cervical stump during supracervical hysterectomy on the postoperative spotting rate and its influence on sexuality and in turn quality of life. METHODS: 321 Patients who underwent a laparoscopic supracervical hysterectomy with conical excision (extended laparoscopic supracervical hysterectomy, eLSH, n = 166, Dormagen hospital) or with straight cervical resection (laparoscopic supracervical hysterectomy, LSH, n = 133, MIC Clinics Berlin) were included. Sexual matters, quality of life parameters and additional questions were recorded before operation, at three months of follow up, and at one year of follow up in both groups using a validated questionnaire (German version of International Consultation on Incontinence Questionnaire Vaginal Symptoms Module, ICIQ_VS). Statistical analysis included the impact and impairment of bleeding on sexuality, quality of life in both groups and co-factors such as vaginal symptoms. RESULTS: 11.3% after eLSH and 15.5% after LSH reported spotting after 1 year. Supracervical hysterectomy significantly improves quality of life and sexuality and a conical excision of the remaining stump is associated with a lower but insignificantly reduced spotting rates. Postoperative spotting has no negative influence on sexual matter score of ICIQ_VS, but reduces the postoperative quality of life focusing on vaginal symptoms in a significant way. CONCLUSION: The improvement of ICIQ_VS scores after supracervical hysterectomy is independent of postoperative spotting, but the quality-of-life score is positively influenced by a reduction in the postoperative spotting rate.

Observation of Photoinduced Terahertz Gain in GaAs Quantum Wells: Evidence for Radiative Two-Exciton-to-Biexciton Scattering.

We have observed photoinduced negative optical conductivity, or gain, in the terahertz frequency range in a GaAs multiple-quantum-well structure in a strong perpendicular magnetic field at low temperatures. The gain is narrow band: it appears as a sharp peak (linewidth <0.45 meV) whose frequency shifts with applied magnetic field. The gain has a circular-polarization selection rule: a strong line is observed for hole-cyclotron-resonance-active polarization. Furthermore, the gain appears only when the exciton 1s state is populated, which rules out intraexcitonic transitions to be its origin. Based on these observations, we propose a possible process in which the stimulated emission of a terahertz photon occurs while two free excitons scatter into one biexciton in an energy and angular-momentum conserving manner.

Laparoscopic pectopexy: a follow-up cyclic biomechanical analysis determining time to functional stability.

INTRODUCTION: Pectopexy, a laparoscopic method for prolapse surgery, showed promising results in previous transient testing by this group. It was shown that a single suture, yielding an ultimate load of 35 N, was equivalent to continuous suturing. This was demonstrated in an in vitro cadaver study. This transient data were used to establish an elastic stress-strain envelope. It was now possible to proceed to dynamic in vitro analysis of this surgical method to establish time to functional stability. METHODS: Cyclic testing of this fixation method was performed on human female embalmed cadaver (cohort 1) and fresh, non-embalmed cadaver (cohort 2) pelvises. The testing envelope was 5-25 N at a speed of 1 mm/s. 100 load regulated cycles were applied. RESULTS: 100 cycles were completed with each model; no overall system failure occurred. Steady state, i.e., functional stability was reached after 14.5 (± 2.9) cycles for the embalmed group and after 19.1 (± 7.2) cycles for the non-embalmed group. This difference was statistically significant p = 0.00025. CONCLUSION: This trial showed in an in vitro cyclic testing of the pectopexy method that functional stability may be achieved after no more than 19.1 cycles of load exposure. When remaining within the established load envelope of below 25 N, patients do not need to fear global fixation failure. Testing did demonstrate differences in non-embalmed and embalmed cadaver testing. Embalmed cadaver testing tends to underestimate time to steady state by 26.3%.

Assembly of trivalent particles under confinement: from an exotic solid phase to a liquid phase at low temperature.

Using computer simulations, we study the phase diagram of a two-dimensional system of disk particles with three patches distributed symmetrically along the particle equator. The geometry of the particles is compatible with a honey-comb lattice at moderately low temperature and pressure, whereas it is expected that the system forms a close-packed triangular lattice at high temperature and pressure. The effect of patch size within the single bond per patch regime was investigated, and it was found that the topology of the phase diagram changes drastically with patch size. Interestingly, in particles with small patches (with a half opening angle of 10°), the fluid transforms upon increasing the pressure into a rather exotic phase that can be understood as a honey-comb lattice whose voids are filled continuously with additional particles that remain, on average, unbound. Eventually, all the voids are occupied so that particles are located at the positions of a triangular lattice, but only two thirds of the particles are orientationally ordered whereas the remaining one third can rotate almost freely as in a plastic crystal. At moderately low temperature, the fluid transforms into a nearly empty honey-comb lattice, whereas at high temperature it transforms directly into the almost filled lattice. Interestingly, for particles with big patches (with a half opening angle of 20°), the honey-comb and triangular lattices are separated by a liquid phase that remains stable down to fairly low temperatures. Less surprisingly, only particles with big patches exhibit an equilibrium gas-liquid separation.

Single-shot terahertz time-domain spectroscopy in pulsed high magnetic fields.

We have developed a single-shot terahertz time-domain spectrometer to perform optical-pump/terahertz-probe experiments in pulsed, high magnetic fields up to 30 T. The single-shot detection scheme for measuring a terahertz waveform incorporates a reflective echelon to create time-delayed beamlets across the intensity profile of the optical gate beam before it spatially and temporally overlaps with the terahertz radiation in a ZnTe detection crystal. After imaging the gate beam onto a camera, we can retrieve the terahertz time-domain waveform by analyzing the resulting image. To demonstrate the utility of our technique, we measured cyclotron resonance absorption of optically excited carriers in the terahertz frequency range in intrinsic silicon at high magnetic fields, with results that agree well with published values.

Development of a construct-based risk assessment framework for genetic engineered crops.

Experience gained in the risk assessment (RA) of genetically engineered (GE) crops since their first experimental introductions in the early nineties, has increased the level of familiarity with these breeding methodologies and has motivated several agencies and expert groups worldwide to revisit the scientific criteria underlying the RA process. Along these lines, the need to engage in a scientific discussion for the case of GE crops transformed with similar constructs was recently identified in Argentina. In response to this need, the Argentine branch of the International Life Sciences Institute (ILSI Argentina) convened a tripartite working group to discuss a science-based evaluation approach for transformation events developed with genetic constructs which are identical or similar to those used in previously evaluated or approved GE crops. This discussion considered new transformation events within the same or different species and covered both environmental and food safety aspects. A construct similarity concept was defined, considering the biological function of the introduced genes. Factors like environmental and dietary exposure, familiarity with both the crop and the trait as well as the crop biology, were identified as key to inform a construct-based RA process.

Pattern formation in binary fluid mixtures induced by short-range competing interactions.

Molecular dynamics simulations and integral equation calculations of a simple equimolar mixture of diatomic molecules and monomers interacting via attractive and repulsive short-range potentials show the existence of pattern formation (microheterogeneity), mostly due to depletion forces away from the demixing region. Effective site-site potentials extracted from the pair correlation functions using an inverse Monte Carlo approach and an integral equation inversion procedure exhibit the features characteristic of a short-range attractive and a long-range repulsive potential. When charges are incorporated into the model, this becomes a coarse grained representation of a room temperature ionic liquid, and as expected, intermediate range order becomes more pronounced and stable.

Rapid scanning terahertz time-domain magnetospectroscopy with a table-top repetitive pulsed magnet.

We have performed terahertz time-domain magnetospectroscopy by combining a rapid scanning terahertz time-domain spectrometer based on the electronically controlled optical sampling method with a table-top minicoil pulsed magnet capable of producing magnetic fields up to 30 T. We demonstrate the capability of this system by measuring coherent cyclotron resonance oscillations in a high-mobility two-dimensional electron gas in GaAs and interference-induced terahertz transmittance modifications in a magnetoplasma in lightly doped n-InSb.

Effect of kinesio taping on jumping and balance in athletes: a crossover randomized controlled trial.

The purpose of this crossover randomized controlled trial was to verify the effect of Kinesio Taping (KT) applied to the triceps surae with the aim to improve muscle performance during vertical jump (VJ), horizontal jump (HJ), and dynamic balance (DB) in healthy college athletes. The participants were 20 athletes (11 men) who competed in 4 different sports modalities (track and field, handball, volleyball, and soccer). Participants had a mean age of 22.3 ± 3.3 years, mean height of 1.74 ± 0.08 m, and mean body mass of 67.8 ± 10.1 kg. The intervention consisted of applying KT from the origin of the triceps surae to its insertion with the purpose of increasing muscle performance, and the placebo consisted of applying tape with nonelastic properties. There were no significant differences between KT and placebo conditions for height (m) in VJ (KT, 0.18 ± 0.06; placebo, 0.17 ± 0.06; p = 0.14), distance (m) in HJ (KT, 1.48 ± 0.3; placebo, 1.47 ± 0.3; p = 0.40), and DB in distance reached (m) in the star excursion balance test, normalized by lower limb length (anterior: KT, 90.0 ± 6.7; placebo, 89.5 ± 7.5; p = 0.56; posterolateral: KT, 92.5 ± 7.5; placebo, 93.2 ± 5.8; p = 0.52; posteromedial: KT, 98.3 ± 6.7; placebo, 98.7 ± 7.4; p = 0.69). The KT technique was not found to be useful in improving performance in some sports-related movements in healthy college athletes; therefore, KT applied to the triceps surae should not be considered by athletes when the sole reason of the application is to increase performance during jumping and balance.

The routes of hysterectomy: A survey of current practices amongst members of the International Society for Gynaecologic Endoscopy (ISGE).

OBJECTIVE: This study aimed to explore the current opinion on the routes of hysterectomy amongst the members of the International Society for Gynaecologic Endoscopy (ISGE), as well as the perceptions of potential barriers that inhibit gynaecologists from offering a minimally invasive hysterectomies (MIHs) to their patients. STUDY DESIGN: An anonymous, electronic survey was designed, including the questions about the surgeon location and length of gynaecological practice, preferred approach to hysterectomy, approximate number of surgical cases performed during the year preceding the survey (2021), and potential barriers and contraindications to performing MIHs. It was validated by 12 practicing gynaecologists. Subsequently, the survey was sent to all practicing gynaecologists who are the members of the ISGE. RESULTS: We received a response from 159 members of ISGE (29 % response rate), of which 92 % with ≥ 5 years in practice since the completion of their residency training in Gynaecology and Obstetrics. When asked about the preferred route of hysterectomy for themselves or their relatives, 59 % chose total laparoscopic hysterectomy (TLH), 19 % vaginal hysterectomy (VH), 8 % chose laparoscopically-assisted vaginal hysterectomy (LAVH) and 5 % chose total abdominal hysterectomy (TAH). However, TAH was the most performed hysterectomy procedure undertaken by the respondents in the year preceding the survey. When asked about the main obstacles to performing MIHs, more than half of the respondents highlighted insufficient training during residency and insufficient surgical experience. Only 25 % of the responders acknowledged reading the ISGE guidelines on performing vaginal hysterectomy. CONCLUSIONS: Contrary to a full understanding of the benefits of MIHs, lack of training, as well as insufficient surgical experience and unawareness of existing evidence-based guidelines were the main reasons for the high rate of TAH among the ISGE members who participated in the study. All efforts should be directed at teaching VH and TLH techniques during residency, continuous acquisition of practical experience, and use of validated patient selection guidelines for MIH in daily clinical practice.

Practice of laparoscopic prolapse surgery in Europe - ESGE Survey.

Sacrocolpopexy is considered as the "gold standard" for management of women with apical prolapse. Numerous technical variants are being practiced. The first aim of this survey was to determine the habits of practice of laparoscopic sacrocolpopexy (LSCP) in Europe. The second aim was to determine whether surgeons who perform laparoscopic pelvic organ prolapse (POP) repair are familiar with the practice of alternative techniques and with mesh-less laparoscopic treatment of prolapse. The questionnaire was designed by the Urogynaecology Special Interest Group of the European Society for Gynaecological Endoscopy (ESGE). All ESGE-members were invited by email to respond to this survey consisting of 54 questions divided in different categories. Following review of ESGE member's responses, we have highlighted the great heterogeneity concerning the practice of LSCP and important variability in performance of concomitant surgeries. Alternative techniques are rarely used in practice. Furthermore, the lack of standardisation of the many surgical steps of a laparoscopic sacrocolpopexy is mainly due to the lack of evidence. There is a need for training and teaching in both standard and newer innovative techniques as well as the reporting of medium and long-term outcomes of both standard laparoscopic sacrocolpopexy and any of its alternatives.

Theory of repulsive charged colloids in slit-pores.

Using classical density functional theory (DFT) we analyze the structure of the density profiles and solvation pressures of negatively charged colloids confined in slit pores. The considered model, which was already successfully employed to study a real colloidal (silica) suspension [S. H. L. Klapp et al., Phys. Rev. Lett. 100, 118303 (2008)], involves only the macroions which interact via the effective Derjaguin-Landau-Verwey-Overbeek (DLVO) potential supplemented by a hard core interaction. The solvent enters implicitly via the screening length of the DLVO interaction. The free energy functional describing the colloidal suspension consists of a hard sphere contribution obtained from fundamental measure theory and a long range contribution which is treated using two types of approximations. One of them is the mean field approximation (MFA) and the remaining is based on Rosenfeld's perturbative method for constructing the Helmholtz energy functional. These theoretical calculations are carried out at different bulk densities and wall separations to compare finally to grand canonical Monte Carlo simulations. We also consider the impact of charged walls. Our results show that the perturbative DFT method yields generally qualitatively consistent and, for some systems, also quantitatively reliable results. In MFA, on the other hand, the neglect of charge-induced correlations leads to a breakdown of this approach in a broad range of densities.

CT and CT angiography in massive haemoptysis with emphasis on pre-embolization assessment.

Massive haemoptysis is a respiratory emergency. Computed tomography angiography (CTA) can play a crucial role in assessing the cause and origin of the haemoptysis and directing the interventional radiologist prior to treatment. The bronchial arterial supply and to a lesser extent the non-bronchial systemic arterial supply are responsible for the majority of cases of massive haemoptysis, but uncommon causes of massive haemoptysis should be considered to avoid misdiagnosis and delayed treatment. Failure to assess the imaging appropriately prior to endovascular treatment may result in early recurrent massive haemoptysis or patient death.

Validity of two methods for estimation of vertical jump height.

The objectives of this study were (a) to determine the concurrent validity of the flight time (FT) and double integration of vertical reaction force (DIF) methods in the estimation of vertical jump height with the video method (VID) as reference; (b) to verify the degree of agreement among the 3 methods; (c) to propose regression equations to predict the jump height using the FT and DIF. Twenty healthy male and female nonathlete college students participated in this study. The experiment involved positioning a contact mat (CTM) on the force platform (FP), with a video camera 3 m from the FP and perpendicular to the sagittal plane of the subject being assessed. Each participant performed 15 countermovement jumps with 60-second intervals between the trials. Significant differences were found between the jump height obtained by VID and the results with FT (p ≤ 0.01) and DIF (p ≤ 0.01), showing that the methods are not valid. Additionally, the DIF showed a greater degree of agreement with the reference method than the FT did, and both presented a systematic error. From the linear regression test was determined the prediction equations with a high degree of linearity between the methods VID vs. DIF (R = 0.988) and VID vs. FT (R = 0.979). Therefore, the prediction equations suggested may allow coaches to measure the vertical jump performance of athletes by the FT and DIF, using a CTM or an FP, which represents more practical and viable approaches in the sports field; comparisons can then be made with the results of other athletes evaluated by VID.

Endometrial effect of progesterone delivered by vaginal rings in estrogen-treated postmenopausal women.

AIM: The type of estrogen and progestin as well as their doses, route and regimens of administration may each affect the benefit-risk profile of postmenopausal hormone therapy. The aim of this study was to evaluate the endometrial effect of progesterone released continuously from a vaginal ring, combined with transdermal estradiol in postmenopausal women. METHOD: Forty-four postmenopausal women participated in a randomized, double-blind, dose-finding study evaluating two hormonal treatments, combining 50 microg/day of estradiol delivered by transdermal patches and either 0.5-g or 1-g progesterone vaginal rings (PVR) given for 12 weeks. The effect on the endometrium was assessed by histology and the detection of the proliferative marker Ki-67. We also measured the serum concentration of estradiol and progesterone, the tissue concentration of progesterone and the immunolocalization of estradiol and progesterone receptors in the endometrium. RESULTS: Endometrial thickness was increased after both treatments, although endometrial histology appeared atrophic in most biopsies. A circulating dose-response of serum progesterone levels was observed from the first to the 12th week of PVR use. In the high-progesterone-dose group, the scarce presence of Ki-67 and hormone receptors reflected the predominant action of progesterone in endometrial glands and stroma, in parallel with a lower tissue concentration of progesterone in this group. CONCLUSION: The PVR appears to be a promising method of administering natural progesterone to postmenopausal women treated with estrogen. Estradiol levels corrected the menopausal symptoms, as expected, and the presence of atrophic endometrium in the majority of women indicated that both doses of progesterone oppose the stimulatory estradiol effects, although the percentage of proliferative tissue was not negligible in both groups.

Phase diagram of a two-dimensional lattice gas model of a ramp system.

Using Monte Carlo simulation and fundamental measure theory we study the phase diagram of a two-dimensional lattice gas model with a nearest neighbor hard core exclusion and a next-to-nearest neighbor finite repulsive interaction. The model presents two competing ranges of interaction and, in common with many experimental systems, exhibits a low density solid phase, which melts back to the fluid phase upon compression. The theoretical approach is found to provide a qualitatively correct picture of the phase diagram of our model system.