Quasichiral Interactions between Quantum Emitters at the Nanoscale.

We present a combined classical and quantum electrodynamics description of the coupling between two circularly polarized quantum emitters held above a metal surface supporting surface plasmons. Depending on their position and their natural frequency, the emitter-emitter interactions evolve from being reciprocal to nonreciprocal, which makes the system a highly tunable platform for chiral coupling at the nanoscale. By relaxing the stringent material and geometrical constraints for chirality, we explore the interplay between coherent and dissipative coupling mechanisms in the system. Thus, we reveal a quasichiral regime in which its quantum optical properties are governed by its subradiant state, giving rise to extremely sharp spectral features and strong photon correlations.

Erratum: Theory of Frequency-Filtered and Time-Resolved N-Photon Correlations [Phys. Rev. Lett. 109, 183601 (2012)].

This corrects the article DOI: 10.1103/PhysRevLett.109.183601.

Exciting Polaritons with Quantum Light.

We discuss the excitation of polaritons-strongly coupled states of light and matter-by quantum light, instead of the usual laser or thermal excitation. As one illustration of the new horizons thus opened, we introduce "Mollow spectroscopy"-a theoretical concept for a spectroscopic technique that consists of scanning the output of resonance fluorescence onto an optical target-from which weak nonlinearities can be read with high precision even in strongly dissipative environments.

Collective fluid dynamics of a polariton condensate in a semiconductor microcavity.

Semiconductor microcavities offer unique systems in which to investigate the physics of weakly interacting bosons. Their elementary excitations, polaritons-mixtures of excitons and photons-can accumulate in macroscopically degenerate states to form various types of condensate in a wide range of experimental configurations, under either incoherent or coherent excitation. Condensates of polaritons have been put forward as candidates for superfluidity, and the formation of vortices as well as elementary excitations with linear dispersion are actively sought as evidence to support this. Here, using a coherent excitation triggered by a short optical pulse, we have created and set in motion a macroscopically degenerate state of polaritons that can be made to collide with a variety of defects present in the microcavity. Our experiments show striking manifestations of a coherent light-matter packet, travelling at high speed (of the order of one per cent of the speed of light) and displaying collective dynamics consistent with superfluidity, although one of a highly unusual character as it involves an out-of-equilibrium dissipative system. Our main results are the observation of a linear polariton dispersion accompanied by diffusionless motion; flow without resistance when crossing an obstacle; suppression of Rayleigh scattering; and splitting into two fluids when the size of the obstacle is comparable to the size of the wave packet. This work opens the way to the investigation of new phenomenology of out-of-equilibrium condensates.

Preoperative chemoradiation with or without induction oxaliplatin plus 5-fluorouracil in locally advanced rectal cancer. Long-term outcome analysis.

BACKGROUND AND PURPOSE: It has been previously reported that a short FOLFOX-4 induction significantly improves pathologic complete response in locally advanced rectal cancer (LARC) patients treated with preoperative chemoradiation (CRT). In a larger and updated patient series, we analyzed FOLFOX-4 efficacy in terms of sphincter preservation and long-term outcomes. PATIENTS AND METHODS: From January 1995 to December 2010, 335 LARC patients were treated with preoperative chemoradiation (4500-5040 cGy). Starting in May 2001, 207 consecutive patients additionally received induction FOLFOX-4. Surgery was performed 6 weeks (range 3-12 weeks) after chemoradiation. RESULTS: Incidence of total tumor (63 vs. 54 %, p = 0.02) and nodal downstaging (60 vs. 43 %, p = 0.002) was significantly increased by induction FOLFOX-4. In an analysis of tumors located below 5 cm from the anal verge (n = 114, 34 %), sphincter preservation was feasible in 30 % in the FOLFOX-4 versus 13 % in the upfront CRT group (p = 0.04). Median follow-up time for the entire cohort of patients was 72.6 months (range 4-205 months). FOLFOX-4 was not associated with superior locoregional control (HR 0.88, p = 0.78), disease-free survival (HR 0.83, p = 0.55), distant metastases-free survival (HR 0.94, p = 0.81), or cancer-specific survival (HR 0.70, p = 0.15). CONCLUSION: Short-intense induction FOLFOX-4 significantly improves downstaging and sphincter preservation in low rectal tumors. Long-term outcomes were not improved in the FOLFOX-4 group of patients.

Ultrafast Control and Rabi Oscillations of Polaritons.

We report the experimental observation and control of space and time-resolved light-matter Rabi oscillations in a microcavity. Our setup precision and the system coherence are so high that coherent control can be implemented with amplification or switching off of the oscillations and even erasing of the polariton density by optical pulses. The data are reproduced by a quantum optical model with excellent accuracy, providing new insights on the key components that rule the polariton dynamics.

Evaluation of bone microarchitecture by high-resolution peripheral quantitative computed tomography (HR-pQCT) in hemodialysis patients.

UNLABELLED: Hemodialyzed patients have decreased bone strength not completely characterized. We evaluated bone microarchitecture in hemodialysis patients and compared it to that of subjects without renal disease by high-resolution peripheral quantitative computed tomography (HR-pQCT). Hemodialysis patients have a marked decreased in cortical density, thickness, and area with significant reduction in trabecular parameters that correlated with the severity of secondary hyperparathyroidism only in women. INTRODUCTION: Although fracture risk is greatly increased in dialysis patients, the corresponding decreased in bone strength has not been completely characterized. METHODS: We evaluated volumetric bone mineral density (vBMD) and bone microstructure by HR-pQCT at the distal radius and tibia in 50 hemodialyzed (HD) patients (30 females, mean age 53.2 ± 6 years and 20 males, mean age 59.1 ± 11 years) and 50 sex- and age-matched controls. RESULTS: At the distal radius HD, women showed a 29% reduction in total and trabecular density and trabecular bone volume fraction (p < 0.0001) compared to controls. Trabecular number was reduced by 25% (p < 0.0001), while trabecular separation was increased by 51%. Cortical thickness (-40%, p < 0.0001) and cortical area (-42%, p < 0.0001) were the parameters most reduced, while compact density was the parameter least reduced (-15%, p < 0.0001). Similar findings were found at the tibia. In HD men, HR-pQCT at the distal radius and tibia showed a reduction in volumetric density and microstructure parameters to a lesser extent than in women. In the hemodialyzed group, cortical thickness at the radius was negatively correlated with age both in women and men. At the distal radius and tibia, we found significant negative correlations between Log iPTH and total alkaline phosphatase with cortical vBMD(r = -0.48, p < 0.01; r = -0.69, p < 0.001), thickness (-0.37, p < 0.05; r = -0.60, p < 0.001), and area ((r = -0.43, p = 0.02; r = -0.65, p < 0.001) but only in women. CONCLUSION: We conclude that hemodialysis patients have a marked decreased in cortical density, thickness, and area with significant reduction in trabecular parameters that correlated with the severity of secondary hyperparathyroidism only in women.

Theory of frequency-filtered and time-resolved N-photon correlations.

A theory of correlations between N photons of given frequencies and detected at given time delays is presented. These correlation functions are usually too cumbersome to be computed explicitly. We show that they are obtained exactly through intensity correlations between two-level sensors in the limit of their vanishing coupling to the system. This allows the computation of correlation functions hitherto unreachable. The uncertainties in time and frequency of the detection, which are necessary variables to describe the system, are intrinsic to the theory. We illustrate the power of our formalism with the example of the Jaynes-Cummings model, by showing how higher order photon correlations can bring new insights into the dynamics of open quantum systems.

Results of European pooled analysis of IORT-containing multimodality treatment for locally advanced rectal cancer: adjuvant chemotherapy prevents local recurrence rather than distant metastases.

BACKGROUND: The purpose of this study is to analyze the pooled results of multimodality treatment of locally advanced rectal cancer (LARC) in four major treatment centers with particular expertise in intraoperative radiotherapy (IORT). PATIENTS AND METHODS: A total of 605 patients with LARC who underwent multimodality treatment up to 2005 were studied. The basic treatment principle was preoperative (chemo)radiotherapy, intended radical surgery, IORT and elective adjuvant chemotherapy (aCT). In uni- and multivariate analyses, risk factors for local recurrence (LR), distant metastases (DM) and overall survival (OS) were studied. RESULTS: Chemoradiotherapy lead to more downstaging and complete remissions than radiotherapy alone (P < 0.001). In all, 42% of the patients received aCT, independent of tumor-node-metastasis stage or radicality of the resection. LR rate, DM rate and OS were 12.0%, 29.2% and 67.1%, respectively. Risk factors associated with LR were no downstaging, lymph node (LN) positivity, margin involvement and no postoperative chemotherapy. Male gender, preoperatively staged T4 disease, no downstaging, LN positivity and margin involvement were associated with a higher risk for DM. A risk model was created to determine a prognostic index for individual patients with LARC. CONCLUSIONS: Overall oncological results after multimodality treatment of LARC are promising. Adding aCT to the treatment can possibly improve LR rates.

Effect of pure dephasing on the Jaynes-Cummings nonlinearities.

We study the effect of pure dephasing on a two-level system in strong coupling in the nonlinear regime with the single mode of a cavity. The photoluminescence spectrum of the cavity has a robust tendency to display triplet structures, instead of the expected Jaynes-Cummings pairs of doublets at the incommensurate frequencies +/- (square root n +/- square root (n-1)) for integer n. We discuss recent experimental works that may already manifest signatures of single photon nonlinearities.

Mollow triplet under incoherent pumping.

A counterpart of the Mollow triplet (luminescence line shape of a two-level system under coherent excitation) is obtained for the case of incoherent excitation in a cavity. The system acquires coherence through the strong-coupling between the cavity and the emitter. Analytical expressions, in excellent agreement with numerical results, pinpoint analogies and differences between the conventional resonance fluorescence spectrum and its cavity QED analogue under incoherent excitation. Most notably, the satellites broaden and split sublinearly with increasing incoherent pumping.

[Results of the treatment of primary glenohumeral osteoarthritis through hemiarthroplasty]. / Resultados del tratamiento de la artrosis glenohumeral primaria mediante hemiartroplastía.

INTRODUCTION: Glenohumeral osteoarthritis leads to a functional loss and a decrease in the quality of life of many patients that suffers it. Currently there is no agreement on the use of hemiarthroplasty or total arthroplasty as definitive treatment. The objective is to show the results of the treatment of primary glenohumeral osteoarthritis through hemiarthroplasty in our service. MATERIAL AND METHODS: We reviewed 14 patients (19 hemiarthroplasties) performed between 2004 and 2013 in patients diagnosed with primary glenohumeral osteoarthritis without glenoid morphological anomaly. We managed to collect data from eight patients (11 hemiarthroplasties), assessing functional status, pain, and performing activities of daily living using the Constant, ASES and DASH scores preoperatively and at five years of minimum follow-up (range 5-11 years), as well as related complications. The preoperative status was compared to the end of the follow-up. RESULTS: A significant improvement was found in all the parameters analyzed in the study (p. CONCLUSION: < 0.05). The average pain in EVA score decreased from 8.89 to 2.67. The ASES improved from 13.51 to 63. 51 half point. The Constant increase of 20.11 points to 65.11 points. The mean preoperative score in the DASH score was 73.68 and 28.30 postoperatively. The average survival of the implant was 81.82% in the seven years of average follow-up. Shoulder hemiarthroplasty obtains good functional results in the treatment of primary glenohumeral osteoarthritis with few complications. The cause of the failure were glenoid erosion in all the cases.

INTRODUCCIÓN: La artrosis glenohumeral conlleva a una pérdida funcional y a una disminución de la calidad de vida de muchos pacientes. Actualmente, no existe consenso en cuanto al uso de la hemiartroplastía o la artroplastía total como tratamiento definitivo para este padecimiento. El objetivo es mostrar los resultados del tratamiento de la artrosis glenohumeral primaria mediante hemiartroplastía en nuestro servicio. MATERIAL Y MÉTODOS: Revisamos 19 hemiartroplastías (14 pacientes) realizadas entre 2004 y 2013 en pacientes con artrosis glenohumeral primaria sin alteración morfológica glenoidea. Se recabaron los datos de ocho pacientes (11 hemiartroplastías), valorándose el estado funcional, el dolor y la realización de actividades de la vida diaria mediante las escalas Constant, ASES y DASH preoperatorias, a los cinco años de seguimiento mínimo (rango 5-11 años), así como las complicaciones presentadas. Se comparó el estado preoperatorio y al final del seguimiento. RESULTADOS: Se encontró una mejoría estadísticamente significativa (p. CONCLUSIÓN: < 0.05) en todos los parámetros analizados en el estudio. La media del dolor en la escala EVA disminuyó de 8.89 a 2.67. La escala ASES mejoró de 13.51 a 63.51 puntos de media. El Constant aumentó de 20.11 a 65.11 puntos. La puntuación media preoperatoria en la escala DASH fue de 73.68 y la postoperatoria de 28.30 puntos. La supervivencia media del implante fue de 81.82% a los siete años de seguimiento medio. Obtuvimos buenos resultados funcionales con la artrosis glenohumeral primaria, presentándose pocas complicaciones. La causa del fracaso fue la erosión glenoidea.

[Use of the radiological exploration in a medical specialities department]. / Utilización de estudios de diagnóstico radiológico en una unidad de especialidades médicas.

BACKGROUND AND OBJECTIVES: To analyse the use of the radiological examinations and the adequacy of every request to the guidelines of indication of radiological investigations. PATIENTS AND METHODS: A prospective survey that includes the explorations carried out in 202 patients hospitalised between January and April of 2006. The demographic data, the diagnosis, the radiological exams, the clinical aim of the requests and the requesting department were analysed. The appropriateness was assessed according to the international criteria of adequacy by two experienced physicians. RESULTS: Twenty-seven percent out of the requests of radiological investigations was no adapted to the reference criteria. The requesting department, the type of radiographies and the diagnostic aim of the radiological studies were associated with an appropriate indication (p < 0.0001). Among the radiographies with diagnostic aim, the detection of radiological alterations was associated with a suitable indication of the request (p < 0.0001). CONCLUSION: The appropriate use of the radiological explorations was similar to other published reports. The inadequate indication seems to be associated with the use of simple radiographic explorations, with follow-up studies and with the requests from Intensive Care Unit.

The colored Hanbury Brown-Twiss effect.

The Hanbury Brown-Twiss effect is one of the celebrated phenomenologies of modern physics that accommodates equally well classical (interferences of waves) and quantum (correlations between indistinguishable particles) interpretations. The effect was discovered in the late thirties with a basic observation of Hanbury Brown that radio-pulses from two distinct antennas generate signals on the oscilloscope that wiggle similarly to the naked eye. When Hanbury Brown and his mathematician colleague Twiss took the obvious step to propose bringing the effect in the optical range, they met with considerable opposition as single-photon interferences were deemed impossible. The Hanbury Brown-Twiss effect is nowadays universally accepted and, being so fundamental, embodies many subtleties of our understanding of the wave/particle dual nature of light. Thanks to a novel experimental technique, we report here a generalized version of the Hanbury Brown-Twiss effect to include the frequency of the detected light, or, from the particle point of view, the energy of the detected photons. Our source of light is a polariton condensate, that allows high-resolution filtering of a spectrally broad source with a high degree of coherence. In addition to the known tendencies of indistinguishable photons to arrive together on the detector, we find that photons of different colors present the opposite characteristic of avoiding each others. We postulate that fermions can be similarly brought to exhibit positive (boson-like) correlations by frequency filtering.

Pharmaceutical industry interactions of psychiatric trainees from 20 European countries.

BACKGROUND: Interactions between the pharmaceutical industry (PI) and psychiatrists have been under scrutiny recently, though there is little empirical evidence on the nature of the relationship and its intensity at psychiatry trainee level. We therefore studied the level of PI interactions and the underlying beliefs and attitudes in a large sample of European psychiatric trainees. METHODS: One thousand four hundred and forty-four psychiatric trainees in 20 European countries were assessed cross-sectionally, with a 62-item questionnaire. RESULTS: The total number of PI interactions in the preceding two months varied between countries, with least interactions in The Netherlands (M (Mean)=0.92, SD=1.44, range=0-12) and most in Portugal (M=19.06, SD=17.44, range=0-100). Trainees were more likely to believe that PI interactions have no impact on their own prescribing behaviour than that of other physicians (M=3.30, SD=1.26 vs. M=2.39, SD=1.06 on a 5-point Likert scale: 1 "completely disagree" to 5 "completely agree"). Assigning an educational role to the pharmaceutical industry was associated with more interactions and higher gift value (IRR (incidence rate ratio)=1.21, 95%CI=1.12-1.30 and OR=1.18, 95%CI=1.02-1.37). CONCLUSIONS: There are frequent interactions between European psychiatric trainees and the PI, with significant variation between countries. We identified several factors affecting this interaction, including attribution of an educational role to the PI. Creating alternative educational opportunities and specific training dedicated to PI interactions may therefore help to reduce the impact of the PI on psychiatric training.

Human rhabdomyosarcoma cells for rapid detection of enteroviruses by shell-vial assay.

The ability of the RD (rhabdomyosarcoma) and MRC-5 cell-lines to detect enteroviruses in 33 clinical samples (cerebrospinal fluid, stools and throat swabs) was evaluated. The samples had previously tested enterovirus-positive by traditional tube-culture and had been frozen after their initial processing. By traditional tube-culture, 100 and 85 % of samples were positive for enterovirus in RD and MRC-5 cells, respectively. By rapid shell-vial assay, 94 and 45.5 % were positive after 48 h incubation in RD and MRC-5 cells, respectively. RD cells supported growth of all enterovirus serotypes, whereas MRC-5 cells were not able to detect any of the three coxsackieviruses that were found (one coxsackievirus A9 and two coxsackievirus B5). The shell-vial assay with RD cell-lines may be a useful tool for rapid diagnosis of enteroviral infection.

The impact of influenza viruses on hospitalizations in infants younger than two years old during epidemics of respiratory syncytial virus infection.

In order to evaluate the association of influenza viruses with hospitalizations for acute respiratory infection in infants younger than two years old during epidemics of respiratory syncytial virus infection, we studied 512 nasal washes from this population. The samples were obtained from 1997 to 2000. A total of 337 viruses were isolated: 264 respiratory syncytial viruses, 62 influenza viruses, eight parainfluenza viruses, two adenovirus and one rhinovirus. Hospitalizations for acute respiratory infection were owing to influenza and respiratory syncytial viruses in 18.3% vs. 78.3% of all cases, and 32.5% vs. 65.8%, respectively, in the group of infants between 6 months and 2 years old.

Pattern of apolipoprotein D immunoreactivity in human brain.

Presence of intracytoplasmatic apolipoprotein D (apo D), a lipophilic ligand transporter, was investigated in normal human brains between 20 and 55 years, using an anti-human apolipoprotein D antibody and extravidin-biotin-enhanced immunohistochemistry. Apo D immunoreactivity was found in neuroglial cells of white matter in all sampled brain regions studied but also in pial cells and perivascular cells. Immunoreactive neurons do not present a uniform pattern throughout the gray matter. The pons and the brainstem show a high immunoreactivity for apo D in several nuclei (olivary, arciforme, cuneado, raphe). In the cerebellum the immunoreactivity appears in some neurons of the Purkinje layer. Finally in the cerebral cortex apo D positive neurons were not observed. These results suggest that apo D role may vary depending of cellular synthesis or location.

[Low gastrointestinal bleeding due to ectopic varices as a result of adhesions]. / Hemorragia digestiva baja por varices ectópicas sobre bridas.

Portal hypertension frequently causes the appearance of porto-systemic shunts, such as esophageal varices and also, but with much less frequency, other atypical shunts known as ectopic varices. Despite their infrequency/rarity, ectopic varices can cause serious gastrointestinal bleeding. Intraabdominal adhesions, especially post-operative ones, promote their appearance. The therapeutic management of ectopic varices is initially the same as that for esophageal varices but surgical treatment is usually necessary as a diagnostic and therapeutic procedure.

[Metabolic changes in 2612 patients with nephrolithiasis]. / Alteraciones metabólicas en 2612 pacientes con litiasis renal.

Nephrolithiasis is one of the most frequent pathologies of the urinary tract. Its prevalence in the city of Buenos Aires is 4%. Different biochemical and physiological disturbances may create an environment conductive to renal stone formation. We present the results of an ambulatory evaluation in 2612 patients for the purpose of updating the classification of nephrolithiasis. An abnormal urinary biochemistry was observed in 2423 patients (92.8%) that could be classified in 15 categories. A single diagnosis was documented in 61.5% of the patients, and the remaining 31.2% had more than one diagnosis (concurrent abnormalities). No abnormality was found in 189 stone formers (7.2%). Idiopathic hypercalciuria was the most frequent abnormality, it was encountered in 31.2%; hyperuricosuria and gouty diathesis (presence of urine pH < 5.5, with normal or high uricemia) accounted for 9.4% and 5.4% of patients, respectively. On the other hand, hypomagnesuria affected 6.7% of the stone formers and hypocitraturia was observed in 4.5%. Primary hyperparathiriodism, hyperoxaluria and cystinuria were seen less frequently in 2.6%, 1.3 and 0.45% of patients. Low urine volume was found in 12% of the patients. Among those patients with more than one abnormality, we found that hypercalciuria together with hyperuricosuria and hypocitraturia (12%) was the prevalent association followed by hypercalciuria with hyperuricosuria (9.1%). Our results show the importance of studying nephrolithiasis patients from a biochemical point of view, since this is the only way to achieve a diagnosis of the metabolic abnormality and introduce a specific therapy to prevent recurrence.