Bandgap Energy of Wurtzite InAs Nanowires.

InAs nanowires (NWs) have been grown on semi-insulating InAs (111)B substrates by metal-organic chemical vapor deposition catalyzed by 50, 100, and 150 nm-sized Au particles. The pure wurtzite (WZ) phase of these NWs has been attested by high-resolution transmission electron microscopy and selected area diffraction pattern measurements. Low temperature photoluminescence measurements have provided unambiguous and robust evidence of a well resolved, isolated peak at 0.477 eV, namely 59 meV higher than the band gap of ZB InAs. The WZ nature of this energy band has been demonstrated by high values of the polarization degree, measured in ensembles of NWs both as-grown and mechanically transferred onto Si and GaAs substrates, in agreement with the polarization selection rules for WZ crystals. The value of 0.477 eV found here for the bandgap energy of WZ InAs agrees well with theoretical calculations.

Postfabrication Tuning of Circular Bragg Resonators for Enhanced Emitter-Cavity Coupling.

Solid-state quantum emitters embedded in circular Bragg resonators are attractive due to their ability to emit quantum light with high brightness and low multiphoton probability. As for any emitter-microcavity system, fabrication imperfections limit the spatial and spectral overlap of the emitter with the cavity mode, thus limiting their coupling strength. Here, we show that an initial spectral mismatch can be corrected after device fabrication by repeated wet chemical etching steps. We demonstrate an ∼16 nm wavelength tuning for optical modes in AlGaAs resonators on oxide, leading to a 4-fold Purcell enhancement of the emission of single embedded GaAs quantum dots. Numerical calculations reproduce the observations and suggest that the achievable performance of the resonator is only marginally affected in the explored tuning range. We expect the method to be applicable also to circular Bragg resonators based on other material platforms, thus increasing the device yield of cavity-enhanced solid-state quantum emitters.

A source of entangled photons based on a cavity-enhanced and strain-tuned GaAs quantum dot.

A quantum-light source that delivers photons with a high brightness and a high degree of entanglement is fundamental for the development of efficient entanglement-based quantum-key distribution systems. Among all possible candidates, epitaxial quantum dots are currently emerging as one of the brightest sources of highly entangled photons. However, the optimization of both brightness and entanglement currently requires different technologies that are difficult to combine in a scalable manner. In this work, we overcome this challenge by developing a novel device consisting of a quantum dot embedded in a circular Bragg resonator, in turn, integrated onto a micromachined piezoelectric actuator. The resonator engineers the light-matter interaction to empower extraction efficiencies up to 0.69(4). Simultaneously, the actuator manipulates strain fields that tune the quantum dot for the generation of entangled photons with corrected fidelities to a maximally entangled state up to 0.96(1). This hybrid technology has the potential to overcome the limitations of the key rates that plague QD-based entangled sources for entanglement-based quantum key distribution and entanglement-based quantum networks. Supplementary Information: The online version contains supplementary material available at 10.1186/s43593-024-00072-8.

Exploring the feasibility of a combined exercise program for patients with advanced lung or pancreatic cancer.

Objective: This study aims to assess the safety, feasibility, and potential benefits of a combined aerobic and resistance exercise intervention for patients diagnosed with advanced pancreatic or lung cancer. Methods: A prospective, single-arm study was conducted, enrolling patients with advanced lung or pancreatic cancer. Participants engaged in a 12-week exercise intervention comprising personalized bi-weekly aerobic and resistance training tailored to individual baseline conditions. The primary study outcomes focused on safety (absence of serious adverse events) and feasibility. Secondary outcomes included assessments of functional capacity using the "Six minutes walking test", strength measured through handgrip and leg press tests, anthropometric measures including body mass index and waist-hip ratio, quality of life (QoL), and changes in blood parameters. Results: The study involved twelve patients (mean age 57.66 â€‹± â€‹7.40 years), with seven having pancreatic cancer and five having lung cancer. The recruitment rate was 50%, and assessment adherence was 100%, with an 84% adherence to the exercise program and no dropouts. No exercise-related adverse events were recorded, while three non-severe, non-exercise-related adverse events were observed: treatment-related dermatitis (Grade 2), axillary lymphadenopathy (Grade 2), and migraine (Grade 1). Significant enhancements in functional capacity, emotional well-being, and social functioning within the QoL domains were observed. Anthropometric measures, specifically waist-hip ratio and body mass index, remained stable. Conclusions: The findings suggest that a tailored 12-week exercise intervention is both feasible and safe for patients with advanced lung or pancreatic cancer. This intervention appears to enhance functional capacity, specific aspects of QoL, and contribute to maintaining body weight.

[Analytical quality of assays and comparison of procedures for the sweat test]. / Qualités analytiques des techniques de dosage et comparaison des procédures utilisées pour le test de la sueur.

Sweat test measuring the chloride ion (Cl(-)) concentration in sweat is a tool for the cystic fibrosis (CF) diagnosis. We evaluated analytical criteria of different available methods and compared them into five hospitals and throught a national quality control program. Sweat tests were performed by stimulation using pilocarpine iontophoresis, sweat collection and measurement of sweat Cl(-) (mmol/L) by titration (colorimetric or coulometric end-point) or by in situ direct potentiometry using a chloride-selective electrode. Indirect determination by sweat conductivity measurement was expressed in mmol/L sodium chloride (NaCl) equivalents (Eq). Linearity range was demonstrated for all measurement procedures in the range 10 to 120 mmol/L. Intra-laboratory coefficients of variation (CVs) were <5% for values between 10 and 100 mmol/L. Inter-laboratory CVs were <3% only for conductivity measurement whatever the range. The comparison of results obtained for a same sweat sample, simultaneously by coulometric and conductivity measurements, demonstrated a first degree linear distribution between 30 to 60 mmol/L Cl(-) allowing us to establish an analytical correspondence table for this range. Thus, calculated values for 30, 40 and 60 mmol/L Cl(-) were respectively 57, 66 and 84 mmol/L NaCl Eq. In conclusion, comparison of methods highlighted that the less the sweat test is automatically controlled, the more the operator influence on results quality is important. Our study supports that sweat test result <50 mmol/L NaCl Eq is unlikely with CF diagnosis in absence of clinical arguments.

Quantum key distribution with entangled photons generated on demand by a quantum dot.

Quantum key distribution-exchanging a random secret key relying on a quantum mechanical resource-is the core feature of secure quantum networks. Entanglement-based protocols offer additional layers of security and scale favorably with quantum repeaters, but the stringent requirements set on the photon source have made their use situational so far. Semiconductor-based quantum emitters are a promising solution in this scenario, ensuring on-demand generation of near-unity-fidelity entangled photons with record-low multiphoton emission, the latter feature countering some of the best eavesdropping attacks. Here, we use a coherently driven quantum dot to experimentally demonstrate a modified Ekert quantum key distribution protocol with two quantum channel approaches: both a 250-m-long single-mode fiber and in free space, connecting two buildings within the campus of Sapienza University in Rome. Our field study highlights that quantum-dot entangled photon sources are ready to go beyond laboratory experiments, thus opening the way to real-life quantum communication.

[Analytical and clinical guidelines on neonatal bilirubinemia]. / Recommandations analytiques et cliniques pour l'utilisation de la bilirubinémie en néonatalogie.

The SFBC-CNBH-CNRHP "Neonatal bilirubin" working group performed a biological and clinical study on bilirubin use in neonates for reliable diagnosis and appropriate management of neonatal jaundice. A brief report of a national survey on analytical and biological practices in France is shown. The guidelines of the French Society of Neonatology (SFN) founded the decision of phototherapy set up upon an accurate lab measurement of total serum bilirubin. An abacus is proposed with defined thresholds, as a function of neonate lifetime in hours. However, several studies evidenced poor comparability of results obtained with the different available methods. This situation is partly due to the lack of reference materials, especially for high bilirubin concentrations. Clinical consequences might be observed. We present in this paper the results of a national harmonization study to progress on this issue. Beyond the analytical aspects, the clinical consequences of harmonization defects were investigated. Finally, guidelines for clinical laboratories are proposed, to be locally adapted.

All-photonic quantum teleportation using on-demand solid-state quantum emitters.

All-optical quantum teleportation lies at the heart of quantum communication science and technology. This quantum phenomenon is built up around the nonlocal properties of entangled states of light that, in the perspective of real-life applications, should be encoded on photon pairs generated on demand. Despite recent advances, however, the exploitation of deterministic quantum light sources in push-button quantum teleportation schemes remains a major open challenge. Here, we perform an important step toward this goal and show that photon pairs generated on demand by a GaAs quantum dot can be used to implement a teleportation protocol whose fidelity violates the classical limit (by more than 5 SDs) for arbitrary input states. Moreover, we develop a theoretical framework that matches the experimental observations and that defines the degree of entanglement and indistinguishability needed to overcome the classical limit independently of the input state. Our results emphasize that on-demand solid-state quantum emitters are one of the most promising candidates to realize deterministic quantum teleportation in practical quantum networks.

[Sweat chloride measurement using direct potentiometry: Spotchem(®) (Elitech-Arkray) evaluation and comparison with coulometry and conductivity]. / Dosage des chlorures sudoraux par potentiométrie directe sur cartouche à usage unique (analyseur Spotchem(®), Elitech-Arkray) : comparaison des résultats à ceux obtenus par coulométrie et par la mesure de la conductivité

Sweat chloride (Cl(-)) measurement is a key step for the diagnosis of cystic fibrosis. The coulometric technique is validated in this context by international guidelines. The aim of our study was to evaluate the assay for sweat Cl(-) ions using direct potentiometry on disposable cassette (Spotchem™ SE EL-1520, Elitech-Arkray) by comparing results to those obtained on the same sample, by coulometry (Chloride analyser Sherwood 926S, Dutscher). To complete our table of correspondence between the results of Cl(-) ions and sweat conductivity (Sweat Check™ 3100), conductivity has been also achieved for 99 of the 139 sweat samples studied. Linearity of each technique performed extends from 10 to 120 mmol/L. The coefficients of variation within and between runs are < 5%. Comparison of 139 results (Passing - Bablock regression) shows a significant difference (p < 0.001): [Spotchem] = 1.026 [Chloride analyser] + 1.8, r = 0.996. After correction with regression factors, only 6 pairs of values (4.6%) had a difference greater than ± 5 mmol/L). The results of conductivity measurement is strongly correlated with those of Cl(-) ions (r = 0.959 for Chloride analyser and 0.965 for Spotchem; p = 0.576) with a linear relationship between the decision thresholds from 30 to 60 mmol/L Cl(-). Sweat Cl(-) determinations using Spotchem™ analyser meet the criteria required by analytical recommendations. The technique is standardized, easy to perform and fast. Its good practicability makes the sweat test independent to operator and allows point-of care use.

Determination of total bilirubin in whole blood from neonates: results from a French multicenter study.

BACKGROUND: Jaundice is frequent in neonates and can cause severe complications, especially in premature neonates, particularly the risk of developing acute bilirubin encephalopathy. Our purpose was to verify if determination of total bilirubin (TBIL) in whole blood on an ABL 735 blood gas analyzer with a spectrophotometer module could provide an analytical alternative to chemical methods of TBIL measurement. METHODS: Our multicenter comparative study involved four hospital laboratories. We studied the repeatability and reproducibility of ABL 735 TBIL measurements in two control sera of medium (N1, 58.1 micromol/L) and high (N2, 275.3 micromol/L) TBIL levels. The same study was simultaneously conducted on four chemistry instruments (two LX 20, one Integra 800 and one Hitachi 917) using four Jendrassik-Grof derived methods. At one site, repeatability was performed with two adult whole-blood samples containing low and high TBIL levels (55.1 and 312.6 micromol/L). RESULTS: Repeatability tests provided coefficients of variation (CVs) between 0.67% and 1.86% on the ABL 735 system, vs. 0.35% and 1.96% for the chemistry instruments. Reproducibility tests for the same control sera resulted in CVs between 1.01% and 3.55% for the ABL 735 and between 0.52% and 3.65% for the chemistry instruments. Recovery for the N1 and N2 control sera was 102-120%. A correlation study of TBIL determination in whole blood vs. plasma was conducted on 473 neonatal blood samples. Correlation coefficients between whole blood and plasma TBIL ranged from 0.969 to 0.994. Passing-Bablok equations were y=1.17x+9.7 [site 1 (IP)], y=1.01x+5.6 [site 2 (JPB, MR)], and y=1.00x-20 [site 3 (AS)]. Only 10% of the results fell outside the 10% range in the bias-corrected Bland-Altman difference plot for the ABL 735 method compared to traditional laboratory methods. CONCLUSIONS: The ABL 735 instrument is reliable for measuring TBIL in 70-microL whole blood samples from neonates. Thus, this method might allow significant blood savings in preterm neonates. Correlation with the reference method for plasma or sera must be established to ensure good follow-up of patients.