Multi-qubit entanglement and algorithms on a neutral-atom quantum computer.

Gate-model quantum computers promise to solve currently intractable computational problems if they can be operated at scale with long coherence times and high-fidelity logic. Neutral-atom hyperfine qubits provide inherent scalability owing to their identical characteristics, long coherence times and ability to be trapped in dense, multidimensional arrays1. Combined with the strong entangling interactions provided by Rydberg states2-4, all the necessary characteristics for quantum computation are available. Here we demonstrate several quantum algorithms on a programmable gate-model neutral-atom quantum computer in an architecture based on individual addressing of single atoms with tightly focused optical beams scanned across a two-dimensional array of qubits. Preparation of entangled Greenberger-Horne-Zeilinger (GHZ) states5 with up to six qubits, quantum phase estimation for a chemistry problem6 and the quantum approximate optimization algorithm (QAOA)7 for the maximum cut (MaxCut) graph problem are demonstrated. These results highlight the emergent capability of neutral-atom qubit arrays for universal, programmable quantum computation, as well as preparation of non-classical states of use for quantum-enhanced sensing.

A new species of Urocleidoides Mizelle & Price, 1964 from the gills of Schizodon nasutus Kner, 1858 (Characiformes, Anostomidae) in southeastern Brazil.

Based on an integrative approach, this study describes a new species of Urocleidoides infesting Schizodon nasutus in the Paranapanema River basin, Brazil. The new species can be distinguished from its congeners by specific morphological features, including the shape of the male copulatory organ and accessory piece, the ventral bar shape, and the shape and size of the hooks. Molecular analyses, particularly of the 28S rDNA gene, suggest a close relationship between the new species and Urocleidoides paradoxus. The phylogenetic and taxonomic arrangement of Urocleidoides is discussed, as the analyses of the 28S rDNA and COI mtDNA resolved the genus as non-monophyletic, with Diaphorocleidus, Rhinoxenus, and Cacatuocotyle nested within it. Additional morphological and molecular data of other congeneric species are required to investigate the phylogenetic position and classification of Urocleidoides. This study underscores the significance of using integrative approaches in understanding host-parasite associations and phylogenetic relationships, contributing to the description of the freshwater fish parasite biodiversity in South America, particularly in the Paranapanema river basin.

An integrative taxonomy study reveals a rare new species of the genus Creptotrema (Trematoda: Allocreadiidae) in an endangered frog in South America.

During an ecological study with a near-endangered anuran in Brazil, the Schmidt's Spinythumb frog, Crossodactylus schmidti Gallardo, 1961, we were given a chance to analyze the gastrointestinal tract of a few individuals for parasites. In this paper, we describe a new species of an allocreadiid trematode of the genus Creptotrema Travassos, Artigas & Pereira, 1928, which possesses a unique trait among allocreadiids (i.e., a bivalve shell-like muscular structure at the opening of the ventral sucker); the new species represents the fourth species of allocreadiid trematode parasitizing amphibians. Besides, the new species is distinguished from other congeners by the combination of characters such as the body size, ventral sucker size, cirrus-sac size, and by having small eggs. DNA sequences through the 28S rDNA and COI mtDNA further corroborated the distinction of the new species. Phylogenetic analyses placed the newly generated sequences in a monophyletic clade together with all other sequenced species of Creptotrema. Genetic divergences between the new species and other Creptotrema spp. varied from 2.0 to 4.2% for 28S rDNA, and 15.1 to 16.8% for COI mtDNA, providing robust validation for the recognition of the new species. Even though allocreadiids are mainly parasites of freshwater fishes, our results confirm anurans as hosts of trematodes of this family. Additionally, we propose the reallocation of Auriculostoma ocloya Liquin, Gilardoni, Cremonte, Saravia, Cristóbal & Davies, 2022 to the genus Creptotrema. This study increases the known diversity of allocreadiids and contributes to our understanding of their evolutionary relationships, host-parasite relationships, and biogeographic history.

First molecular assessment on Cosmocerca spp. from Brazilian anurans and description of a new species of Cosmocerca (Ascaridomorpha: Cosmocercoidea) from the white-spotted humming frog Chiasmocleis albopunctata (Boettger, 1885) (Anura: Microhylidae).

Cosmocerca spp. are common nematode parasites of amphibians. We provide herein molecular data for two species of Cosmocerca and describe a new species, Cosmocerca albopunctata n. sp., using light microscopy and molecular data (cytochrome c oxidase subunit 1 - COI mtDNA). Cosmocerca albopunctata n. sp. can be easily distinguished from other congeneric species by the combination of characteristics such as body size, length of spicules and gubernaculum, and the arrangements and number of caudal papillae (7 + 1:1 + 1:6). The phylogenetic results based on the partial COI mtDNA sequences clustered the new species in a monophyletic clade along with the other sequences of Cosmocerca spp. Therefore, our results contribute to the knowledge about the species diversity and genetic data for Cosmocerca spp. in the Neotropical region.

Study into the spread of heat from thermo-optic silicon photonic elements.

Phase modulators based upon the thermo-optic effect are used widely in silicon photonics for low speed applications such as switching and tuning. The dissipation of the heat produced to drive the device to the surrounding silicon is a concern as it can dictate how compact and tightly packed components can be without concerns over thermal crosstalk. In this paper we study through modelling and experiment, on various silicon on insulator photonic platforms, how close waveguides can be placed together without significant thermal crosstalk from adjacent devices.

Integration of low loss vertical slot waveguides on SOI photonic platforms for high efficiency carrier accumulation modulators.

Silicon accumulation type modulators offer prospects of high power efficiency, large bandwidth and high voltage phase linearity making them promising candidates for a number of advanced electro-optic applications. A significant challenge in the realisation of such a modulator is the fabrication of the passive waveguide structure which requires a thin dielectric layer to be positioned within the waveguide, i.e. slotted waveguides. Simultaneously, the fabricated slotted waveguide should be integrated with conventional rib waveguides with negligible optical transition losses. Here, successful integration of polysilicon and silicon slot waveguides enabling a low propagation loss 0.4-1.2 dB/mm together with an ultra-small optical mode conversion loss 0.04 dB between rib and slot waveguides is demonstrated. These fabricated slot waveguide with dielectric thermal SiO2 layer thicknesses around 6 nm, 8 nm and 10 nm have been characterized under transmission electron microscopy allowing for strong carrier accumulation effects for MOS-capacitor electro-optic modulators.

A clinical decision support system improves antibiotic therapy for upper urinary tract infection in a randomized single-blinded study.

BACKGROUND: Due to increasing bacterial resistance rates choosing a correct empiric antibiotic therapy is getting more and more complex. Often medical doctors use information tools to make the right treatment choice. METHODS: One hundred sixty six participants (77 medical doctors and 89 medical students) were asked to provide a diagnosis and antibiotic therapy in a simple fictive paper case of upper urinary tract infection (UTI) in a randomized single-blinded study. Participants were randomized to one of four information tools they were allowed to use in the study or control: 1. free internet access, 2. pharmaceutical pocket guide, 3. pocket guide antibiotic therapy, 4. clinical decision support system (CDSS), and control (no information tool). The CDSS was designed for the study. The adherence to the national German UTI guideline was evaluated. RESULTS: Only 27.1% (n = 45/166) provided a correct diagnosis of upper UTI and 19.4% (n = 32/166) an antibiotic treatment recommended by national German treatment guidelines indicating their need for information tools. This result was not significantly different between medical doctors and medical students, residents and medical specialists or level of working experience. Using CDSS improved results significantly compared to conventional tools (diagnosis 57.1%; treatment recommendation 40.5%; p < 0,01). Processing time was not different between the use of CDSS and conventional information tools. CDSS users based their decision making on their assigned information tool more than users of conventional tools (73.8% vs. 48.0%; p < 0.01). Using CDSS improved the confidence of participants in their recommendation significantly compared to conventional tools (p < 0.01). CONCLUSIONS: Our study suggests that medical professionals require information tools in diagnosing and treating a simple case of upper UTI correctly. CDSS appears to be superior to conventional tools as an information source.

Rydberg-Mediated Entanglement in a Two-Dimensional Neutral Atom Qubit Array.

We demonstrate high fidelity two-qubit Rydberg blockade and entanglement on a pair of sites in a large two-dimensional qubit array. The qubit array is defined by a grid of blue detuned lines of light with 121 sites for trapping atomic qubits. Improved experimental methods have increased the observed Bell state fidelity to F_{Bell}=0.86(2). Accounting for errors in state preparation and measurement we infer a fidelity of F_{Bell}^{-SPAM}=0.88. Accounting for errors in single qubit operations we infer that a Bell state created with the Rydberg mediated C_{Z} gate has a fidelity of F_{Bell}^{C_{Z}}=0.89. Comparison with a detailed error model based on quantum process matrices indicates that finite atom temperature and laser noise are the dominant error sources contributing to the observed gate infidelity.

Test of the Einstein Equivalence Principle near the Galactic Center Supermassive Black Hole.

During its orbit around the four million solar mass black hole Sagittarius A* the star S2 experiences significant changes in gravitational potential. We use this change of potential to test one part of the Einstein equivalence principle: the local position invariance (LPI). We study the dependency of different atomic transitions on the gravitational potential to give an upper limit on violations of the LPI. This is done by separately measuring the redshift from hydrogen and helium absorption lines in the stellar spectrum during its closest approach to the black hole. For this measurement we use radial velocity data from 2015 to 2018 and combine it with the gravitational potential at the position of S2, which is calculated from the precisely known orbit of S2 around the black hole. This results in a limit on a violation of the LPI of |ß_{He}-ß_{H}|=(2.4±5.1)×10^{-2}. The variation in potential that we probe with this measurement is six magnitudes larger than possible for measurements on Earth, and a factor of 10 larger than in experiments using white dwarfs. We are therefore testing the LPI in a regime where it has not been tested before.

Multichannel ZnO nanowire field effect transistors by lift-off process.

This paper describes a new, low-cost, top-down fabrication process, which makes it possible to define nanowire field effect transistor arrays with different numbers of nanowires simultaneously and systematically comparing their electrical performance. The main feature of this process is a developed bilayer photoresist pattern with a retrograde profile, which enables the modification of the nanowire in width, length, height and the number of transistor channels. The approach is compatible with low-cost manufacture without electron beam lithography, and benefits from process temperatures below 190 °C. Process reliability has been investigated by scanning electron microscopy, transmission electron microscopy and atomic force microscopy. Electrical measurements demonstrate enhancement mode transistors, which show a scalable correlation between the number of nanowires and the electrical characteristics. Devices with 100 nanowires exhibit the best performance with a high field effect mobility of 11.0 cm2 Vs-1, on/off current ratio of 3.97 × 107 and subthreshold swing of 0.66 V dec-1.

[Follow-up care for gastrointestinal tumors]. / Nachsorge bei gastrointestinalen Tumoren.

The follow-up care of patients with gastrointestinal cancer is poorly defined. Prospective trials showing that regular follow-up care is advantageous are largely lacking. Follow-up is primarily based on symptom evaluation, as well as on an assessment of nutritional status and the need for psycho-oncological care. Whereas the evidence for regular endoscopic follow-up is well defined in early cancers, the role of follow-up care in advanced cancers is less well defined. This deficit is mainly due to the lack of therapeutic consequences in the case of recurrence. In such cases, cure is only rarely possible, and most studies have failed to demonstrate a survival benefit following standardized follow-up care of these patients. However, in view of the evolving treatment options in recurrent disease and the success of recurrent colorectal cancer treatment, it seems reasonable to define the current status of follow-up care for patients with gastrointestinal cancers.

Gemcitabine combined with the monoclonal antibody nimotuzumab is an active first-line regimen in KRAS wildtype patients with locally advanced or metastatic pancreatic cancer: a multicenter, randomized phase IIb study.

BACKGROUND: This randomized study was designed to investigate the superiority of gemcitabine (gem) plus nimotuzumab (nimo), an anti-epidermal growth factor receptor monoclonal antibody, compared with gem plus placebo as first-line therapy in patients with advanced pancreatic cancer. PATIENTS AND METHODS: Patients with previously untreated, unresectable, locally advanced or metastatic pancreatic cancer were randomly assigned to receive gem: 1000 mg/m2, 30-min i.v. once weekly (d1, 8, 15; q29) and nimo: fixed dose of 400 mg once weekly as a 30-min infusion, or gem plus placebo, until progression or unacceptable toxicity. The primary end point was overall survival (OS), secondary end points included time to progression, overall response rate, safety and quality of life. RESULTS: A total of 192 patients were randomized, with 186 of them being assessable for efficacy and safety (average age 63.6 years). One-year OS/progression-free survival (PFS) was 34%/22% for gem plus nimo compared with 19%/10% for gem plus placebo (HR = 0.69; P = 0.03/HR = 0.68; P = 0.02). Median OS/PFS was 8.6/5.1 months for gem plus nimo versus 6.0/3.4 mo in the gem plus placebo group (HR = 0.69; P = 0.0341/HR = 0.68; P = 0.0163), with very few grade 3/4 toxicities. KRAS wildtype patients experienced a significantly better OS than those with KRAS mutations (11.6 versus 5.6 months, P = 0.03). CONCLUSION: This randomized study showed that nimo in combination with gem is safe and well tolerated. The 1-year OS and PFS rates for the entire population were significantly improved. Especially, those patients with KRAS wildtype seem to benefit. The study was registered as protocol ID OSAG101-PCS07, NCT00561990 and EudraCT 2007-000338-38.

Radiation therapists' and radiation oncology medical physicists' perceptions of work and the working environment in Australia: a qualitative study.

Workforce recruitment and retention are issues in radiation oncology. The working environment is likely to have an impact on retention; however, there is a lack of research in this area. The objectives of this study were to: investigate radiation therapists' (RTs) and radiation oncology medical physicists' (ROMPs) perceptions of work and the working environment; and determine the factors that influence the ability of RTs and ROMPs to undertake their work and how these factors affect recruitment and retention. Semi-structured interviews were conducted and thematic analysis was used. Twenty-eight RTs and 21 ROMPs participated. The overarching themes were delivering care, support in work, working conditions and lifestyle. The overarching themes were mostly consistent across both groups; however, the exemplars reflected the different roles and perspectives of RTs and ROMPs. Participants described the importance they placed on treating patients and improving their lives. Working conditions were sometimes difficult with participants reporting pressure at work, large workloads and longer hours and overtime. Insufficient staff numbers impacted on the effectiveness of staff, the working environment and intentions to stay. Staff satisfaction is likely to be improved if changes are made to the working environment. We make recommendations that may assist departments to support RTs and ROMPs.

Effects of zoledronic acid versus placebo on bone mineral density and bone texture analysis assessed by the trabecular bone score in premenopausal women with breast cancer treatment-induced bone loss: results of the ProBONE II substudy.

UNLABELLED: Changes in bone mineral density (BMD) and trabecular bone score (TBS) were assessed in 70 patients who received either zoledronate (ZOL) (n = 34) or placebo (n = 36) for 2 years. In premenopausal women with breast cancer treatment-induced bone loss, 24 months of intravenous ZOL treatment significantly increased the lumbar spine BMD and the TBS. INTRODUCTION: The aim of this study was to compare the effects of 4 mg intravenous zoledronate (ZOL) versus placebo (PLB), every 3 months, on the lumbar spine (LS) bone mineral density (BMD) and the trabecular bone score (TBS) in premenopausal women with breast cancer (BC) treatment-induced bone loss. The TBS is a gray-level texture measurement which is related to the bone microarchitecture and considered to be independent of the BMD. METHODS: Changes in BMD and TBS were assessed in 70 patients who were recruited in the double-blind, placebo-controlled ProBONE-II trial and randomized to receive either ZOL (n = 34) or PLB (n = 36) for 2 years. The changes were assessed at baseline and at 12 and 24 months after treatment initiation. RESULTS: Patients receiving ZOL showed a mean increase in LS BMD from the baseline to 12 (2.17%) and 24 months (3.14%) of treatment and a mean increase in the TBS of 2.41 and 0.75%, respectively. Conversely, patients receiving PLB showed a mean decrease in the LS BMD from the baseline to 12 (-5.02%) and 24 (-6.43%) months and a mean decrease of -0.52 and -2.16% in the TBS, respectively. Changes in the BMD and the TBS from the baseline to 12 and 24 months were all significantly different for ZOL compared to PLB (p < 0.005). Furthermore, BMD and TBS showed a moderate correlation ranging from 0.28 (p = 0.087) to 0.47 (p = 0.003). CONCLUSIONS: In premenopausal women with BC, 24 months of intravenous ZOL treatment significantly increased the LS BMD as well as the TBS.

Coherence and Rydberg Blockade of Atomic Ensemble Qubits.

We demonstrate |W⟩ state encoding of multiatom ensemble qubits. Using optically trapped Rb atoms, the T_{2} coherence time is 2.6(3) ms for N[over ¯]=7.6 atoms and scales approximately inversely with the number of atoms. Strong Rydberg blockade between two ensemble qubits is demonstrated with a fidelity of 0.89(1), and with a fidelity of ∼1.0 when postselected on a control ensemble excitation. These results are a significant step towards deterministic entanglement of atomic ensembles.

Fusobacterium nucleatum associates with stages of colorectal neoplasia development, colorectal cancer and disease outcome.

Commensal bacteria in the colon may play a role in colorectal cancer (CRC) development. Recent studies from North America showed that Fusobacterium nucleatum (Fn) infection is over-represented in disease tissue versus matched normal tissue in CRC patients. Using quantitative real-time polymerase chain reaction (qPCR) of DNA extracted from colorectal tissue biopsies and surgical resections of three European cohorts totalling 122 CRC patients, we found an over-abundance of Fn in cancerous compared to matched normal tissue (p < 0.0001). To determine whether Fn infection is an early event in CRC development, we assayed Fn in colorectal adenoma (CRA) tissue from 52 Irish patients. While for all CRAs the Fn level was not statistically significantly higher in disease versus normal tissue (p = 0.06), it was significantly higher for high-grade dysplasia (p = 0.015). As a secondary objective, we determined that CRC patients with low Fn levels had a significantly longer overall survival time than patients with moderate and high levels of the bacterium (p = 0.008). The investigation of Fn as a potential non-invasive biomarker for CRC screening showed that, while Fn was more abundant in stool samples from CRC patients compared to adenomas or controls, the levels in stool did not correlate with cancer or adenoma tissue levels from the same individuals. This is the first study examining Fn in the colonic tissue and stool of European CRC and CRA patients, and suggests Fn as a novel risk factor for disease progression from adenoma to cancer, possibly affecting patient survival outcomes. Our results highlight the potential of Fn detection as a diagnostic and prognostic determinant in CRC patients.

Recurrence after endoscopic mucosal resection-therapy failure?

PURPOSE: To evaluate the success and complication rates of endoscopic mucosal resections (EMR) for large flat adenomas and to identify risk factors for adenoma recurrence. METHODS: We evaluated all consecutive patients treated with EMR at our institution between 2003 and 2005 that fulfilled the following criteria: >10-mm diameter, Paris 0-Is and 0-IIa-c, and endoscopic follow-up. We conducted univariate analysis and multivariate analysis using a non-stratified logistic regression model to identify possible influencing factors. RESULT: In a median follow-up period of 6 years, we analyzed 177 EMR procedures, with a mean size of 21 mm. The majority of the resections were in the right colon. Recurrence occurred in 29 patients. Further treatment of patients with recurrence was endoscopic in 27 patients, whereas 1 patient was treated with transanal endoscopic microsurgery and one underwent surgery. The variables influencing the multivariate model were resection technique, immediate complication age, and histology. CONCLUSIONS: We show that EMR can achieve a long-term clearance of large flat adenomas. A recurrence after EMR does not equal to failed therapy. The possibility of recurrence has to be considered in the clinical implementation of EMR. An important part of the stratifying factors for follow-up is the procedural assessment of the effectiveness of the resection and the resection technique.

[Sexually transmitted infections as a cause for solid rectal pseudo tumors]. / Sexuell übertragbare Infektionen als Ursache von solide imponierenden Pseudotumoren des Rektums.

Two cases of symptomatic proctitis with rectal tumors suspicious for malignancy are presented. A florid regenerative proctitis was shown in the histological examination. In both cases a sexually transmitted infection (STI) was causing the symptoms. In rare cases STIs present as pseudo tumors mimicking malignancy in clinical examination and endoscopic/radiological analysis. A close collaboration between gastroenterologist and pathologist is necessary for a correct diagnosis and to prevent unnecessary surgical treatment.

[Standards for diagnostics and therapy of gastric cancer]. / Standards der Diagnostik und Therapie des Magenkarzinoms.

Despite a decreasing frequency gastric cancer is the fifth or sixth most common cancer in Germany. Usually the cancer is discovered in an advanced stage. This article is based primarily on the current S3 guidelines for gastric cancer published 2011. General aspects of risk factors, diagnosis and therapy with the current classification system are the main topics in this article. Furthermore, this article focuses on treatment of local advanced disease. Especially in recent years, many studies have dealt with the concept of perioperative treatment. However, a worldwide standard of care could not be reached for this indication.

Training and assessing convolutional neural network performance in automatic vascular segmentation using Ga-68 DOTATATE PET/CT.

To evaluate a convolutional neural network's performance (nnU-Net) in the assessment of vascular contours, calcification and PET tracer activity using Ga-68 DOTATATE PET/CT. Patients who underwent Ga-68 DOTATATE PET/CT imaging over a 12-month period for neuroendocrine investigation were included. Manual cardiac and aortic segmentations were performed by an experienced observer. Scans were randomly allocated in ratio 64:16:20 for training, validation and testing of the nnU-Net model. PET tracer uptake and calcium scoring were compared between segmentation methods and different observers. 116 patients (53.5% female) with a median age of 64.5 years (range 23-79) were included. There were strong, positive correlations between all segmentations (mostly r > 0.98). There were no significant differences between manual and AI segmentation of SUVmean for global cardiac (mean ± SD 0.71 ± 0.22 vs. 0.71 ± 0.22; mean diff 0.001 ± 0.008, p > 0.05), ascending aorta (mean ± SD 0.44 ± 0.14 vs. 0.44 ± 0.14; mean diff 0.002 ± 0.01, p > 0.05), aortic arch (mean ± SD 0.44 ± 0.10 vs. 0.43 ± 0.10; mean diff 0.008 ± 0.16, p > 0.05) and descending aorta (mean ± SD < 0.001; 0.58 ± 0.12 vs. 0.57 ± 0.12; mean diff 0.01 ± 0.03, p > 0.05) contours. There was excellent agreement between the majority of manual and AI segmentation measures (r ≥ 0.80) and in all vascular contour calcium scores. Compared with the manual segmentation approach, the CNN required a significantly lower workflow time. AI segmentation of vascular contours using nnU-Net resulted in very similar measures of PET tracer uptake and vascular calcification when compared to an experienced observer and significantly reduced workflow time.