Influence functions for a hysteretic deformable mirror with a high-density 2D array of actuators.

We present modeling and analysis of a hysteretic deformable mirror where the facesheet interacts with a continuous layer of piezoelectric material that can be actuated distributively by a matrix of electrodes through multiplexing. Moreover, a method to calculate the actuator influence functions is described considering the particular arrangement of electrodes. The results are presented in a semi-analytical model to describe the facesheet's deformation caused by a high-density array of actuators, and validated in a simulation. The proposed modeling of an interconnection layout of electrodes is used to determine the optimal pressures the actuators must exert to achieve a desired surface deformation.

Measurement of the full distribution of persistent current in normal-metal rings.

We have measured the persistent current in individual normal metal rings over a wide range of magnetic fields. From this data, we extract the first six cumulants of the single-ring persistent current distribution. Our results are consistent with the prediction that this distribution should be nearly Gaussian for diffusive metallic rings. This measurement highlights the sensitivity of persistent current to the mesoscopic fluctuations within a single isolated coherent volume.

Quantum state tomography of an itinerant squeezed microwave field.

We perform state tomography of an itinerant squeezed state of the microwave field prepared by a Josephson parametric amplifier (JPA). We use a second JPA as a preamplifier to improve the quantum efficiency of the field quadrature measurement from 2% to 36%±4%. Without correcting for the detection inefficiency we observe a minimum quadrature variance which is 68(-7)(+9)% of the variance of the vacuum. We reconstruct the state's density matrix by a maximum likelihood method and infer that the squeezed state has a minimum variance less than 40% of the vacuum, with uncertainty mostly caused by calibration systematics.

2D and 3D X-ray phase retrieval of multi-material objects using a single defocus distance.

A method of tomographic phase retrieval is developed for multi-material objects whose components each has a distinct complex refractive index. The phase-retrieval algorithm, based on the Transport-of-Intensity equation, utilizes propagation-based X-ray phase contrast images acquired at a single defocus distance for each tomographic projection. The method requires a priori knowledge of the complex refractive index for each material present in the sample, together with the total projected thickness of the object at each orientation. The requirement of only a single defocus distance per projection simplifies the experimental setup and imposes no additional dose compared to conventional tomography. The algorithm was implemented using phase contrast data acquired at the SPring-8 Synchrotron facility in Japan. The three-dimensional (3D) complex refractive index distribution of a multi-material test object was quantitatively reconstructed using a single X-ray phase-contrast image per projection. The technique is robust in the presence of noise, compared to conventional absorption based tomography.

Digital Control of a Superconducting Qubit Using a Josephson Pulse Generator at 3 K.

Scaling of quantum computers to fault-tolerant levels relies critically on the integration of energy-efficient, stable, and reproducible qubit control and readout electronics. In comparison to traditional semiconductor-control electronics (TSCE) located at room temperature, the signals generated by rf sources based on Josephson-junctions (JJs) benefit from small device sizes, low power dissipation, intrinsic calibration, superior reproducibility, and insensitivity to ambient fluctuations. Previous experiments to colocate qubits and JJ-based control electronics have resulted in quasiparticle poisoning of the qubit, degrading the coherence and lifetime of the qubit. In this paper, we digitally control a 0.01-K transmon qubit with pulses from a Josephson pulse generator (JPG) located at the 3-K stage of a dilution refrigerator. We directly compare the qubit lifetime T 1, the coherence time T 2 * , and the thermal occupation P th when the qubit is controlled by the JPG circuit versus the TSCE setup. We find agreement to within the daily fluctuations of ±0.5 µs and ±2 µs for T 1 and T 2 * , respectively, and agreement to within the 1% error for P th. Additionally, we perform randomized benchmarking to measure an average JPG gate error of 2.1 × 10-2. In combination with a small device size (< 25 mm2) and low on-chip power dissipation (≪100 µW), these results are an important step toward demonstrating the viability of using JJ-based control electronics located at temperature stages higher than the mixing-chamber stage in highly scaled superconducting quantum information systems.

Synaptic weighting in single flux quantum neuromorphic computing.

Josephson junctions act as a natural spiking neuron-like device for neuromorphic computing. By leveraging the advances recently demonstrated in digital single flux quantum (SFQ) circuits and using recently demonstrated magnetic Josephson junction (MJJ) synaptic circuits, there is potential to make rapid progress in SFQ-based neuromorphic computing. Here we demonstrate the basic functionality of a synaptic circuit design that takes advantage of the adjustable critical current demonstrated in MJJs and implement a synaptic weighting element. The devices were fabricated with a restively shunted Nb/AlOx-Al/Nb process that did not include MJJs. Instead, the MJJ functionality was tested by making multiple circuits and varying the critical current, but not the external shunt resistance, of the oxide Josephson junction that represents the MJJ. Experimental measurements and simulations of the fabricated circuits are in good agreement.

Erratum to: The management of intra-abdominal infections from a global perspective: 2017 WSES guidelines for management of intra-abdominal infections.

[This corrects the article DOI: 10.1186/s13017-017-0141-6.].

Erratum to: Antimicrobials: a global alliance for optimizing their rational use in intra-abdominal infections (AGORA).

[This corrects the article DOI: 10.1186/s13017-016-0089-y.].

Long-term follow-up of tension-free Lichtenstein hernioplasty: application of a qualitative-and-quantitative measurement instrument.

Real outcomes for the inguinal tension-free Lichtenstein hernioplasty are not reflected by the usual parameters by which they are measured and habitually reported. It is possible to measure these outcomes from the point of view of the surgeon, as well as from the patient's, using an instrument specifically designed for that purpose. The aim of this study was to analyze the outcomes of the tension-free hernioplasty in 236 patients. Based upon the concept of quality-of-life, we designed a structured questionnaire in the form of a qualitative-and-quantitative measurement instrument. The study had two phases. First, we analyzed retrospectively the clinical records. Second, we interviewed the patients applying the instrument. The score demonstrated that 83% of the patients feel that the outcomes of their surgery are excellent, 9.7% feel that they are very good, and 3.8% feel that they are bad or very bad. Outcomes of the Lichtenstein hernioplasty should not only reflect the technological progress of hernia surgery but also the more intimate aspects of the patient's experience. It is possible to measure the outcomes of this common surgical procedure in a more complete way using a simple measurement instrument.

[Bone tumors. Their prevalence]. / Tumores óseos. Prevalencia.

1,200 cases of bone tumors were reviewed from the Orthopedic Hospital "Magdalena de las Salinas" between 1982 and 1989. 66.7% of them were benign tumors, 14.3% pseudotumoral lesions, 10.1% metastatic tumors, 8.6% primary malignant tumors, and 0.3% were malignant invasive tumors to bone. The most frequently found benign tumors were: osteochondroma, enchondroma and giant cell tumor; the most frequent pseudotumoral lesions were metaphyseal fibrous defects, solitary bone cysts and fibrous dysplasia; the most frequent primary malignant tumor was osteosarcoma. Prevalence, frequency, distribution, sex, most frequent ages, affected bones, multicentricity, and aggregated fractures, as well as the site of the primary lesion in metastatic and invading tumors, were similar to those reported in the classical series.

Outcomes of open intraperitoneal incisional hernia repair based on patient-reported outcomes.

PURPOSE: The outcomes of open incisional hernia repair from the patients' point of view have variations over time, and only continuous follow-up would reflect the real outcomes. The purpose of this study is to validate a standard measurement instrument in the form of a questionnaire to report the evolutionary outcomes of a specific open technique to repair incisional hernias. METHODS: Prospective study follows up a cohort of 82 consecutive patients submitted to elective intraperitoneal open hernioplasty of midline incisional hernias. The follow-up consisted in an interview and physical examination 30 days after surgery, at 6 months, 1 year, 2 years, 3 years, and 4 years. Primary outcome measure was reporting the outcomes of hernia repair according to a standardized scale obtained from a questionnaire. RESULTS: There was no correlation between complications suffered by patients and score results (p = 0.722). The length of hospital stay was 6.5 ± 4.3 days, and a prolonged hospital stay was related to complications (p = 0.002) and did not influence the score results (p = 0.365). The final score demonstrated that patients had a very good impression on this procedure 1 month after surgery (p = 0.003). This impression shifted to an excellent perception 1 year after surgery remaining similar until the last control (p < 0.0001). CONCLUSIONS: In this series, the intraperitoneal hernioplasty was a procedure associated with minor morbidity and without recurrences 4 years after the operation. The outcomes from the patients' point of view were excellent 1 year after the procedure with a tendency to improve in the long term.

Fabrication and characterization of large arrays of mesoscopic gold rings on large-aspect-ratio cantilevers.

We have fabricated large arrays of mesoscopic metal rings on ultrasensitive cantilevers. The arrays are defined by electron beam lithography and contain up to 10(5) rings. The rings have a circumference of 1 µm, and are made of ultrapure (6N) Au that is deposited onto a silicon-on-insulator wafer without an adhesion layer. Subsequent processing of the SOI wafer results in each array being supported at the end of a free-standing cantilever. To accommodate the large arrays while maintaining a low spring constant, the cantilevers are nearly 1 mm in both lateral dimensions and 100 nm thick. The extreme aspect ratio of the cantilevers, the large array size, and the absence of a sticking layer are intended to enable measurements of the rings' average persistent current ⟨I⟩ in the presence of relatively small magnetic fields. We describe the motivation for these measurements, the fabrication of the devices, and the characterization of the cantilevers' mechanical properties. We also discuss the devices' expected performance in measurements of ⟨I⟩.

[Reversible cerebral vasoconstriction syndrome secondary to secreting jugular paraganglioma]. / Sindrome de vasoconstriccion cerebral reversible secundario a un paraganglioma yugular secretor de metanefrinas.

TITLE: Sindrome de vasoconstriccion cerebral reversible secundario a un paraganglioma yugular secretor de metanefrinas.

Interface-specific x-ray phase retrieval tomography of complex biological organs.

We demonstrate interface-specific propagation-based x-ray phase retrieval tomography of the thorax and brain of small animals. Our method utilizes a single propagation-based x-ray phase-contrast image per projection, under the assumptions of (i) partially coherent paraxial radiation, (ii) a static object whose refractive indices take on one of a series of distinct values at each point in space and (iii) the projection approximation. For the biological samples used here, there was a 9-200 fold improvement in the signal-to-noise ratio of the phase-retrieved tomograms over the conventional attenuation-contrast signal. The ability to 'digitally dissect' a biological specimen, using only a single phase-contrast image per projection, will be useful for low-dose high-spatial-resolution biomedical imaging of form and biological function in both healthy and diseased tissue.

Nanomechanical motion measured with an imprecision below that at the standard quantum limit.

Nanomechanical oscillators are at the heart of ultrasensitive detectors of force, mass and motion. As these detectors progress to even better sensitivity, they will encounter measurement limits imposed by the laws of quantum mechanics. If the imprecision of a measurement of the displacement of an oscillator is pushed below a scale set by the standard quantum limit, the measurement must perturb the motion of the oscillator by an amount larger than that scale. Here we show a displacement measurement with an imprecision below the standard quantum limit scale. We achieve this imprecision by measuring the motion of a nanomechanical oscillator with a nearly shot-noise limited microwave interferometer. As the interferometer is naturally operated at cryogenic temperatures, the thermal motion of the oscillator is minimized, yielding an excellent force detector with a sensitivity of 0.51 aN Hz(-1/2). This measurement is a critical step towards observing quantum behaviour in a mechanical object.

Abdominal compartment syndrome in patients with strangulated hernia.

BACKGROUND: Intestinal obstruction (IO) leads to increased intra-abdominal pressure and abdominal compartment syndrome. The purpose of this study was to investigate the characteristics of abdominal compartment syndrome in patients with IO secondary to strangulated hernia. METHODS: We studied 81 consecutive unselected patients presenting complicated hernias and IO. We measured intra-abdominal pressure using the intra-vesicular pressure method. RESULTS: Preoperative (15 min) intra-abdominal pressure was higher in patients with strangulated hernias. Postoperative (15 min) intra-abdominal pressure in both groups decreased to similar values. Intra-abdominal pressure was measured during the preoperative period in patients with strangulated hernias and during the postoperative period at 15 min (13.8 +/- 6.4 mmHg), 24 h (9.8 +/- 3.2 mmHg) and 48 h (7.4 +/- 2.4 mmHg). Abdominal compartment syndrome developed in 47% cases with strangulated hernias with a mortality of five patients. CONCLUSIONS: Serial measurements of intra-abdominal pressure evidenced the clinical severity of strangulated hernia. Intra-abdominal pressure measurement may be used as a predictor of intestinal strangulation in patients presenting acute abdominal compartment syndrome secondary to complicated hernia.