First Dark Matter Search Results from the LUX-ZEPLIN (LZ) Experiment.

The LUX-ZEPLIN experiment is a dark matter detector centered on a dual-phase xenon time projection chamber operating at the Sanford Underground Research Facility in Lead, South Dakota, USA. This Letter reports results from LUX-ZEPLIN's first search for weakly interacting massive particles (WIMPs) with an exposure of 60 live days using a fiducial mass of 5.5 t. A profile-likelihood ratio analysis shows the data to be consistent with a background-only hypothesis, setting new limits on spin-independent WIMP-nucleon, spin-dependent WIMP-neutron, and spin-dependent WIMP-proton cross sections for WIMP masses above 9 GeV/c^{2}. The most stringent limit is set for spin-independent scattering at 36 GeV/c^{2}, rejecting cross sections above 9.2×10^{-48} cm at the 90% confidence level.

The impact of accuracy and precision of analytical test methods on the determination of withdrawal periods.

Treatment of food-producing animals with veterinary medicinal products (VMPs) can result in residues in foodstuffs (e.g. eggs, meat, milk, or honey) representing a potential consumer health risk. To ensure consumer safety, worldwide regulatory concepts for setting safe limits for residues of VMPs e.g. as tolerances (US) or maximum residue limits (MRLs, EU) are used. Based on these limits so-called withdrawal periods (WP) are determined. A WP represents the minimum period of time required between the last administration of the VMP and the marketing of foodstuff. Usually, WPs are estimated using regression analysis based on residue studies. With high statistical confidence (usually 95% in the EU and 99% in the US) the residues in almost all treated animals (usually 95%) have to be below MRL when edible produce is harvested. Here, uncertainties from both sampling and biological variability are taken into account but uncertainties of measurement associated with the analytical test methods are not systematically considered. This paper describes a simulation experiment to investigate the extent to which relevant sources of measurement uncertainty (accuracy and precision) can impact the length of WPs. A set of real residue depletion data was artificially 'contaminated' with measurement uncertainty related to permitted ranges for accuracy and precision. The results show that both accuracy and precision had a noticeable effect on the overall WP. Due consideration of sources of measurement uncertainty may improve the robustness, quality and reliability of calculations upon which regulatory decisions on consumer safety of residues are based.

[Detection of malnutrition in geriatric trauma patients : A reassessment]. / Erfassung von Mangelernährung bei geriatrischen Traumapatienten : Eine erneute Bestandsaufnahme.

BACKGROUND AND OBJECTIVE: Malnutrition in geriatric trauma patients is associated with an increased risk of complications and mortality and is therefore a key risk factor. The assessment of the affected patients plays an important role in improving the outcome of this growing patient group. MATERIAL AND METHODS: In 2016 a questionnaire was sent to 571 departments specialized in traumatology and orthopedics throughout Germany. The following were recorded: level of care, expertise in geriatric trauma, nutrition-based screening procedures and nutritional ward round procedures. RESULTS: The response rate was 57% (n = 325) and closely reflected the treatment reality in Germany with respect to the level of care (superregional, regional or local trauma center and those without special qualifications). In 14% (n = 45) the participants were German Society for Trauma Surgery(DGU)-certified centers for age-related traumatology, while a further 5% (n = 15) were in the process of certification. The nutritional status was assessed in 56% (n = 181) of the clinics. Most frequently used was the body mass index (74%) followed by the mini nutritional assessment (30%), laboratory parameters (29%) and nutritional risk screening 2002 (19%). Some additional methods were specified. In approximately half of the departments nutritional ward rounds took place in regular wards (50%) and intensive care units (57%). DISCUSSION: The high response rate of this study seems to show the particular interest for malnutrition in geriatric trauma patients. This is reflected in an increase in the participating clinics compared to past surveys and also the more regularly performed assessment of nutritional status and implementation of nutritional visits. CONCLUSION: The establishment of suitable and time-effective screening instruments and their implementation are still a challenge.

Quantitative Agreement between Electron-Optical Phase Images of WSe_{2} and Simulations Based on Electrostatic Potentials that Include Bonding Effects.

The quantitative analysis of electron-optical phase images recorded using off-axis electron holography often relies on the use of computer simulations of electron propagation through a sample. However, simulations that make use of the independent atom approximation are known to overestimate experimental phase shifts by approximately 10%, as they neglect bonding effects. Here, we compare experimental and simulated phase images for few-layer WSe_{2}. We show that a combination of pseudopotentials and all-electron density functional theory calculations can be used to obtain accurate mean electron phases, as well as improved atomic-resolution spatial distribution of the electron phase. The comparison demonstrates a perfect contrast match between experimental and simulated atomic-resolution phase images for a sample of precisely known thickness. The low computational cost of this approach makes it suitable for the analysis of large electronic systems, including defects, substitutional atoms, and material interfaces.

Determination of the 3D shape of a nanoscale crystal with atomic resolution from a single image.

Although the overall atomic structure of a nanoscale crystal is in principle accessible by modern transmission electron microscopy, the precise determination of its surface structure is an intricate problem. Here, we show that aberration-corrected transmission electron microscopy, combined with dedicated numerical evaluation procedures, allows the three-dimensional shape of a thin MgO crystal to be determined from only one single high-resolution image. The sensitivity of the reconstruction procedure is not only sufficient to reveal the surface morphology of the crystal with atomic resolution, but also to detect the presence of adsorbed impurity atoms. The single-image approach that we introduce offers important advantages for three-dimensional studies of radiation-sensitive crystals.

Complex Nanotwin Substructure of an Asymmetric Σ9 Tilt Grain Boundary in a Silicon Polycrystal.

Grain boundaries in materials have substantial influences on device properties, for instance on mechanical stability or electronic minority carrier lifetime in multicrystalline silicon solar cells. This applies especially to asymmetric, less ordered or faceted interface portions. Here, we present the complex atomic interface structure of an asymmetric Σ9 tilt grain boundary in silicon, observed by high resolution scanning transmission electron microscopy (HR-STEM) and explained by atomistic modeling and computer simulation. Structural optimization of interface models for the asymmetric Σ9 and related symmetrical Σ9 and Σ3 tilt grain boundaries, by means of molecular-statics simulations with empirical silicon potentials in combination with first-principles calculations, results in a faceted asymmetric interface structure, whose grain-boundary energy is so low that it is likely to exist. The simulated local atomic structures match the observed HR-STEM images very well.

Oncological outcomes of nephron sparing nephrectomy. 17-year analysis.

OBJECTIVES: Nephron sparing renal surgery is considered the technique of choice for renal tumors smaller than 4 cm. We present our oncological results in a 17-year period. METHODS: Between January 1995 and December 2012, 130 renal tumor surgeries (58 open, 72 laparoscopic) were performed. We analize the pathological results, presence of positive surgical margins, local relapse, distant metastases and death. RESULTS: The most frequent tumor was clear cell carcinoma (73%) in a pT1 stage (87%). Mean tumor size was 3 cm. Positive surgical margin rate was 7%, currently without any tumor recurrence among these cases (follow up 37 months). Cancer specific mortality is 0% and local recurrence rate 3%. Mean follow up is 71 months. CONCLUSIONS: Nephron sparing surgery results are similar to radical nephrectomy in tumors smaller than 4 cm. Positive surgical margins do not seem to have an important repercussion in cancer specific survival.

Trocar site herniation of the small bowel after laparoscopic bilateral adnexectomy despite fascial closure: a case report.

In this paper we report a case of an incarcerated hernia occurring through the peritoneal and muscular defect caused by a previous trocar insertion. The patient developed the hernia eight days after bilateral laparoscopic adnexectomy and presented small bowel obstruction signs. This hernia occurred despite correct closure of the internal oblique fascia. The patient was re-operated and exploratory laparoscopy confirmed the diagnosis. The hernia was reduced via a small extension of the previous incision, and the defect was repaired by separated stitches. This case shows that a trocar site hernia can appear despite correct closure of the fascia, which is poorly described except for obese patients. It suggests the need for careful closure of the abdominal wall including the peritoneum after a laparoscopic procedure. Trocar site hernia has to be considered in cases of post laparoscopic small bowel obstruction. We reviewed the literature and found no randomized control study concerning this problem: only reviews, retrospective studies, case reports and technical notes. These papers are discussed and compared with our case.

Impact of growth kinetics on the interface morphology and magnetization in La1/3Sr2/3FeO3/La2/3Sr1/3MnO3 heterostructures.

The ability to create atomically perfect, epitaxial heterostructures of correlated complex perovskite oxides using state-of-art thin film deposition techniques has generated new physical phenomena at engineered interfaces. Here we report on the impact of growth kinetics on the magnetic structure and exchange coupling at the interface in heterostructures combining layers of antiferromagnetic La1/3Sr2/3FeO3 (LSFO) and ferromagnetic La2/3Sr1/3MnO3 (LSMO) on (0 0 1)-oriented SrTiO3 (STO) substrates. Two growth orders are investigated, (a) LSMO/LSFO/STO(0 0 1) and (b) LSFO/LSMO/STO(0 0 1), where the LSFO layer is grown by molecular beam epitaxy and the LSMO layer by high oxygen pressure sputtering. The interface has been investigated using electron microscopy and polarized neutron reflectometry. Interdiffusion over seven monolayers is observed in LSMO/LSFO (a) with an almost 50% reduction in magnetization at the interface and showing no exchange coupling. However, the exchange bias effect ([Formula: see text] mT at 10 K) could be realized when the interface is atomically sharp, as in LSFO/LSMO (b). Our study therefore reveals that, even for well ordered and lattice-matched structures, the kinetics involved in the growth processes drastically influences the interface quality with a strong correlation to the magnetic properties.

[Laparoscopic urinary diversions]. / Derivaciones urinarias laparoscópicas.

INTRODUCTION: The treatment of the invasive bladder cancer and the recurrent T1G3 is clearly established in radical cystectomy and pelvic linphadenectomy. One of the fields where the laparoscopic approach implies more doubts is the treatment of bladder cancer, because it requires experience enough in pelvic laparoscopic surgery and the urinary diversion implies great technical difficulties to the laparoscopic approach. OBJECTIVES: The main goal of this article is to report our results with the urinary diversion after laparoscopic radical cystectomy where the ureteral anastomosis has been performed by a laparoscopic approach. METHODS: From January 2005 to December 2007 we have performed 67 laparoscopic radical cistectomies. We conducted 28 laparoscopic urinary diversions with our technique: 7 neobladder with an average age of 54, 85 years and 21 ileal conduit with an average age of 69, 15 years. RESULTS: The averagesurgical time for enterocistoplasty with laparoscopic urethral and ureteral anastomosis is of 5 hours and 30 minutes. For the cutaneous ureteroileostomy with laparoscopic ureteral anastomosis the average surgical time has been of 4 hours and 30 minutes. We have had 1 case of urinary leakage in the laparoscopic neobladder and 3 cases in the laparoscopic ileal conduit (14%). We have not intestinal dehiscence nor ileal-ureteric stenosis. The average hospital stay for laparoscopic neobladder is for the 85% of cases of 13.6 days, and of 11.8 days for the 77.7% of ileal ureteric laparoscopies. DISCUSSION: The laparoscopic radical cystectomy is still a procedure reserved for groups with great experience in laparoscopic surgery. Nowadays, the most accepted procedure by most groups includes perform the cystectomy by a laparoscopic approach and the urinary diversion by an open approach. There is no evidence of the advantages of laparoscopic urinary diversion. It is necessary to perform comparative studies to clearly define the role of laparoscopic surgery in the urinary diversion.

[Experimental laparoscopic renal autograft as learning laparoscopic model]. / Autotrasplante renal laparoscópico experimental como modelo de aprendizaje de técnica laparoscópica.

INTRODUCTION: Laparoscopic surgery requires a long training period of time in which the complexity of the training is increased. GOALS: The technique presented in this paper has been developed in order to find an experimental model that allows us to improve the learning of the vascular suture. Our main goal was to evaluate this technique as an experimental model for the vacular anastomosis, not to obtain a functional autotransplant. In this regard, here we summarize our experience during the first two cases performed. MATERIAL AND METHODS: Laparoscopic renal autotransplant was perfomed in female lab pigs weighing 15-20 kg. International Experimental Animal Care rules were accomplished. RESULTS: After sacrifizing the animals, only one case of vascular thrombosis was observed. The other cases showed normal arterial and venous flow. CONCLUSIONS: Experimental Renal Laparoscopic autotransplant constitutes a good surgical model. We are trying to implement the technique in the clinics in the next future.

[Leukemic infiltration of the urinary bladder. A new case and literature review]. / Infiltración vesical por leucemia linfoblástica aguda. A propósito de un caso y revisión de la literatura.

We expose you one case of leukemic infiltration of the urinary bladder. This kind of infiltration is rare so we reviewed the literature finding 14 cases since 1932. Although this hematological infiltration is very unusual, it should be considered in patients with leukemia and hematuria.

Dr. Probe: A software for high-resolution STEM image simulation.

The Dr. Probe software for multislice simulations of STEM images is introduced, and reference is given of the applied methods. Major program features available with the graphical user interface version are demonstrated by means of a few examples for bright-field and dark-field STEM imaging as well as simulations of diffraction patterns. The numerical procedure applied for the simulation of thermal-diffuse scattering by the frozen-lattice approach is described in detail. Intensity variations occurring in simulations with atomic-column resolution due to frozen-lattice variations are discussed in the context of atom counting. It is found that a significant averaging over many lattice configurations with different random atomic displacements is required to prevent atom-counting bias from simulations. A strategy is developed for the assessment of the amount of required averaging based on the estimated signal variance and the expected signal gain per atom in a column.

One year after proximal or distal periprosthetic fracture of the femur -two conditions with divergent outcomes?

INTRODUCTION: Arthroplasty of the hip and knee is 1 of the 20 most frequent operations in Germany. Periprosthetic fracture is one of the most feared complications following primary or revision arthroplasty. Present publication aims to analyse differences between patients with periprosthetic fracture around total knee arthroplasty (PFTKA) and patients with periprosthetic fracture around total hip arthroplasty (PFTHA) concerning demographics, clinical course, complications and return to pre-fracture mobility. METHODS: Prospective single-centre observation study of periprosthetic femoral fractures with stable implants. Present subgroup analysis includes patients with PFTKA and PFTHA. All patients were treated with polyaxial angular stable plates using two standardized techniques: a minimally invasive percutaneous distal insertion technique and a mini-open technique. Data collection included implant- and operation-related information as well as demographics, clinical course, complications and return to pre-fracture mobility. Data were collected during a 12-month follow-up. RESULTS: We were able to analyse the data of 73 patients. The PFTKA group had 37 patients with a mean age of 76 ±â€¯10 years; 88% were female. After 1 year, 3 patients in this cohort had died; 68% of survivors had reached their pre-fracture mobility; 22% had undergone operative revisions for various reasons. The PFTHA cohort included 36 patients with a mean age of 80 ±â€¯13 years, 72% were female. After 1 year, 9 patients had died in this cohort, 42% of survivors had reached their pre-fracture mobility. Non-operative complications occurred for 16% in the PFTKA group and 64% in the PFTHA group (p < 0.001). 11% had undergone operative revisions for various reasons, among them, two cases of nonunion but no primary infection. CONCLUSION: On average, compared to the PFTHA patients, PFTKA patients were younger, underwent significantly lower rates of non-operative complications, had a tendency towards lower mortality, and returned to pre-fracture mobility at higher rates, although they tended to have more revisions when compared to treatment for PFTHA. Overall, when periprosthetic fractures of the femur were treated using polyaxial locking plate osteosynthesis, patients showed very low rates of nonunion and no primary infection.

[Laparoscopic augmentation enterocystoplasty: initial experience]. / Enterocistoplastia de ampliación laparoscópica: experiencia inicial.

OBJECTIVE: To analyze the initial experience of our group in the realization of the augmentation enterocystoplasty by laparoscopyc approach. METHODS AND PATIENTS: We describe the augmentation enterocystoplasty technique with ileal segment completely achieved by laparoscopyc approach. We present the cases of two patients suffering from hyperreflexic bladder refractory to medical treatment who underwent this surgery. In both cases the technique was realized without intraoperative complications although it was needed a surgical time of 6 and 4.5 hours respectively. The results after 12 and 5 months were satisfactory in both patients, obtaining a low pressure bladder with a good continence. CONCLUSIONS: Laparoscopyc augmentation enterocystoplasty is a complicated technique that requires a great experience, mainly in laparoscopyc suture. It reproduces completely the open surgery and it offers all the advantages inherent to the laparoscopyc surgery.

[Laparoscopic nephron sparing surgery. Initial experience]. / Cirugía renal laparoscópica conservadora de parénquima. Experiencia inicial.

We present our initial experience in laparoscopic nephron sparing surgery. It's a technically advanced procedure requiring considerable minimally invasive expertise. This technique is particularly attractive compared to an open conventional procedure with its larger incision and associated morbidity.

Atomic resolution elemental mapping using energy-filtered imaging scanning transmission electron microscopy with chromatic aberration correction.

This paper addresses a novel approach to atomic resolution elemental mapping, demonstrating a method that produces elemental maps with a similar resolution to the established method of electron energy-loss spectroscopy in scanning transmission electron microscopy. Dubbed energy-filtered imaging scanning transmission electron microscopy (EFISTEM) this mode of imaging is, by the quantum mechanical principle of reciprocity, equivalent to tilting the probe in energy-filtered transmission electron microscopy (EFTEM) through a cone and incoherently averaging the results. In this paper we present a proof-of-principle EFISTEM experimental study on strontium titanate. The present approach, made possible by chromatic aberration correction, has the advantage that it provides elemental maps which are immune to spatial incoherence in the electron source, coherent aberrations in the probe-forming lens and probe jitter. The veracity of the experiment is supported by quantum mechanical image simulations, which provide an insight into the image-forming process. Elemental maps obtained in EFTEM suffer from the effect known as preservation of elastic contrast, which, for example, can lead to a given atomic species appearing to be in atomic columns where it is not to be found. EFISTEM very substantially reduces the preservation of elastic contrast and yields images which show stability of contrast with changing thickness. The experimental application is demonstrated in a proof-of-principle study on strontium titanate.

Surface reconstructions and related local properties of a BiFeO3 thin film.

Coupling between lattice and order parameters, such as polarization in ferroelectrics and/or polarity in polar structures, has a strong impact on surface relaxation and reconstruction. However, up to now, surface structures that involve the termination of both matrix polarization and polar atomic planes have received little attention, particularly on the atomic scale. Here, we study surface structures on a BiFeO3 thin film using atomic-resolution scanning transmission electron microscopy and spectroscopy. Two types of surface structure are found, depending on the polarization of the underlying ferroelectric domain. On domains that have an upward polarization component, a layer with an Aurivillius-Bi2O2-like structural unit is observed. Dramatic changes in local properties are measured directly below the surface layer. On domains that have a downward polarization component, no reconstructions are visible. Calculations based on ab initio density functional theory reproduce the results and are used to interpret the formation of the surface structures.

[Development of a laparoscopic radical prostatectomy program in an university center]. / Implantación de un programa de prostatectomía radical laparoscópica.

The aim of this article is to report our experience in setting up a laparoscopic radical prostatectomy programme. We believe that knowledge of the difficulties we faced at the start will be useful for those who wish to implement a programme like ours. We hope that by explaining the steps we took as well as our conclusions and recommendations this difficult task can be made easier.

[Analysis of a laparoscopic radical prostatectomy program with 544 cases]. / Prostatectomía radical laparoscópica. Revisión de la literatura. Nuestra experiencia.

INTRODUCTION: This article reviews the latest publications that refer to Laparoscopic Radical Prostatectomy (LRP) up to 2005, and describes our series of patients for this type of surgery. MATERIALS AND METHODS: After a search of the Internet and consulting journals of renowned prestige, we selected articles that refer to this technique and we summarise the latest developments in LRP. We also present our series of patients. RESULTS: In view of the good oncologic and functional results obtained with LRP, and the possibility of performing hernioplasty as in open surgery, this technique provides a high quality service for patients. CONCLUSIONS: Due to the advances in the safety and quality of this technique, such as the use of robots, 3 CCD cameras, and the surgeon's experience, LRP should be offered to our patients, if it is within our means.