Certified Quantum Measurement of Majorana Fermions.

We present a quantum self-testing protocol to certify measurements of fermion parity involving Majorana fermion modes. We show that observing a set of ideal measurement statistics implies anti-commutativity of the implemented Majorana fermion parity operators, a necessary prerequisite for Majorana detection. Our protocol is robust to experimental errors. We obtain lower bounds on the fidelities of the state and measurement operators that are linear in the errors. We propose to analyze experimental outcomes in terms of a contextuality witness W, which satisfies 〈W〉 ≤ 3 for any classical probabilistic model of the data. A violation of the inequality witnesses quantum contextuality, and the closeness to the maximum ideal value 〈W〉 = 5 indicates the degree of confidence in the detection of Majorana fermions.

Robust age estimation of southern sea otters from multiple morphometrics.

Reliable age estimation is an essential tool to assess the status of wildlife populations and inform successful management. Aging methods, however, are often limited by too few data, skewed demographic representation, and by single or uncertain morphometric relationships. In this study, we synthesize age estimates in southern sea otters Enhydra lutris nereis from 761 individuals across 34 years of study, using multiple noninvasive techniques and capturing all life stages from 0 to 17 years of age. From wild, stranded, and captive individuals, we describe tooth eruptions, tooth wear, body length, nose scarring, and pelage coloration across ontogeny and fit sex-based growth functions to the data. Dental eruption schedules provided reliable and identifiable metrics spanning 0.3-9 months. Tooth wear was the most reliable predictor of age of individuals aged 1-15 years, which when combined with total length, explained >93% of observed age. Beyond age estimation, dental attrition also indicated the maximum lifespan of adult teeth is 13‒17 years, corresponding with previous estimates of life expectancy. Von Bertalanffy growth function model simulations of length at age gave consistent estimates of asymptotic lengths (male Loo  = 126.0‒126.8 cm, female Loo  = 115.3‒115.7 cm), biologically realistic gestation periods (t 0 = 115 days, SD = 10.2), and somatic growth (male k = 1.8, SD = 0.1; female k = 2.1, SD = 0.1). Though exploratory, we describe how field radiographic imaging of epiphyseal plate development or fusions may improve aging of immature sea otters. Together, our results highlight the value of integrating information from multiple and diverse datasets to help resolve conservation problems.

Understanding the effects of Covid-19 through a life course lens.

The Covid-19 pandemic is shaking fundamental assumptions about the human life course in societies around the world. In this essay, we draw on our collective expertise to illustrate how a life course perspective can make critical contributions to understanding the pandemic's effects on individuals, families, and populations. We explore the pandemic's implications for the organization and experience of life transitions and trajectories within and across central domains: health, personal control and planning, social relationships and family, education, work and careers, and migration and mobility. We consider both the life course implications of being infected by the Covid-19 virus or attached to someone who has; and being affected by the pandemic's social, economic, cultural, and psychological consequences. It is our goal to offer some programmatic observations on which life course research and policies can build as the pandemic's short- and long-term consequences unfold.

Quantum gate teleportation between separated qubits in a trapped-ion processor.

Large-scale quantum computers will require quantum gate operations between widely separated qubits. A method for implementing such operations, known as quantum gate teleportation (QGT), requires only local operations, classical communication, and shared entanglement. We demonstrate QGT in a scalable architecture by deterministically teleporting a controlled-NOT (CNOT) gate between two qubits in spatially separated locations in an ion trap. The entanglement fidelity of our teleported CNOT is in the interval (0.845, 0.872) at the 95% confidence level. The implementation combines ion shuttling with individually addressed single-qubit rotations and detections, same- and mixed-species two-qubit gates, and real-time conditional operations, thereby demonstrating essential tools for scaling trapped-ion quantum computers combined in a single device.

Wild sea otter mussel pounding leaves archaeological traces.

Wild sea otters (Enhydra lutris) are the only marine mammals that habitually use stones while foraging, using them to break open hard-shelled foods like marine snails and bivalves. However, the physical effects of this behavior on local environments are unknown. We show that sea otters pounding mussels on tidally emergent rocks leave distinct material traces, which can be recognized using methods from archaeology. We observed sea otters pounding mussels at the Bennett Slough Culverts site, California, USA, over a l0-year period. Sea otters repeatedly used the same rocks as anvils, which resulted in distinctive wear patterns on the rocks and accumulations of broken mussel shells, all fractured in a characteristic way, below them. Our results raise the potential for discovery of similar sea otter pounding sites in areas that no longer have resident sea otter populations.

Quantum Process Fidelity Bounds from Sets of Input States.

We investigate the problem of bounding the quantum process fidelity given bounds on the fidelities between target states and the action of a process on a set of pure input states. We formulate the problem as a semidefinite program and prove convexity of the minimum process fidelity as a function of the errors on the output states. We characterize the conditions required to uniquely determine a process in the case of no errors, and derive a lower bound on its fidelity in the limit of small errors for any set of input states satisfying these conditions. We then consider sets of input states whose one-dimensional projectors form a symmetric positive operator-valued measure (POVM). We prove that for such sets the minimum fidelity is bounded by a linear function of the average output state error. A symmetric POVM with minimal number of elements contains d + 1 states, where d is the Hilbert space dimension. Our bounds applied to such states provide an efficient method for estimating the process fidelity without the use of full process tomography.

Chemical Looping Combustion Using Two Different Perovskite Based Oxygen Carriers: A Pilot Study.

Two perovskite type oxygen carriers, for the application in chemical looping combustion, called C14 and C28 are investigated. The composition of C14 is CaMn0.9Mg0.1O3-δ and CaMn0.775Mg0.1Ti0.125O3-δ for C28, respectively. Both oxygen carriers allow chemical looping with oxygen uncoupling (CLOU), they release oxygen under conditions with low oxygen partial pressure. The materials are tested in a 120 kWth pilot plant at TU Wien. Operating temperatures from 800 °C to 960 °C are investigated, further the influence of active inventory and air equivalence number is reviewed. In addition to the experiments in the pilot plant, particle analysis is performed. In total, the CLC operation for C14 was 29.5 h and 22.7 h for C28, resulting in 75 different operating points. Both oxygen carrier materials are able to fully convert the natural gas, used as fuel. A temperature dependency is noticeable for both, the best results are achieved at 960 °C, the highest investigated temperature. Both, C14 and C28 are able to release about 10 % of the total available oxygen via oxygen uncoupling. The performance of both oxygen carriers is strongly linked to the air equivalence number and the resulting amount of excess oxygen in the air reactor. Low oxygen partial pressures lead to incomplete fuel conversion.

Patients' decision-making in a UK specialist centre with high mastectomy rates.

A national audit identified one breast cancer unit as having the highest mastectomy rate in the UK: 50% compared to a national average of 14% for cancers <15mm in diameter. This anomaly needed investigation. A questionnaire was sent within 2 years of their surgery to 189 breast cancer patients probing perceived surgical choice, factors in decision-making and usefulness of information. One hundred thirty-one (69%) replied, of these 97 (74%) felt they had choice of surgery. Of these, the most important factor was minimising worry about recurrence. However, only 16% knew that recurrence rates were different between types of surgery. Sixty-one percent felt their healthcare professionals had surgical preferences for them, believed that clinical issues determined these preferences, but still knew the choice was theirs. The extent to which surgical choice is offered and patients are made aware that it is their choice, may account for the high mastectomy rate in this unit.

Chlorophylls of the c family: absolute configuration and inhibition of NADPH:protochlorophyllide oxidoreductase.

Using circular dichroism (CD) spectroscopy, the stereochemistry at C-13(2) of members of the chlorophyll (Chl) c family, namely Chls c(1), c(2), c(3) and [8-vinyl]-protochlorophyllide a (Pchlide a) was determined. By comparison with spectra of known enantiomers, all Chl c members turned out to have the (R) configuration, which is in agreement with considerations drawn from chlorophyll biosynthesis. Except for a double bond in the side chain at C-17, the chemical structure of Chl c(1) is identical with Pchlide a, the natural substrate of the light-dependent NADPH:protochlorophyllide oxidoreductase (POR). Thus, lack of binding to the active site due to the wrong configuration at C-13(2), which had been proposed previously, cannot be an explanation for inactivity of Chl c in this enzymic reaction. Our results show rather that Chl c(1) is a competitive inhibitor for this enzyme, tested with Pchlide a and Zn-protopheophorbide a (Zn-Ppheide a) as substrates.

Helminth parasites of the southern sea otter Enhydra lutris nereis in central California: abundance, distribution and pathology.

From October 1997 to May 2001, the gastrointestinal tracts from 162 beach-cast southern sea otters Enhydra lutris nereis were examined for helminth parasites and associated lesions. Carcasses were collected opportunistically in central California between Pt. San Pedro and Pt. Arguello. The primary goals of this study were to examine spatial and temporal variability in mortality due to parasite infection, identify factors associated with increased risk of infection, and illustrate the process of intestinal perforation by Profilicollis spp. Two genera and 4 species of acanthocephalans (Profilicollis altmani, P. kenti, P. major, Corynosoma enhydri) were found in 46.3% (Profilicollis spp.) and 94.4% (C. enhydri) of the carcasses examined. Three species of Digenea (Microphallus pirum, M. nicolli, Plenosoma minimum) were found in 47% of carcasses, at times in massive numbers (> 3000 per cm2). This is the first report of the latter 2 species from the sea otter. Mortality resulting from infection by Profilicollis spp. occurred in 13.0% (n = 21) of sampled carcasses, either directly, due to perforation of the intestinal wall and peritonitis (9.9%, n = 16), or indirectly, due to inhibition of host nutrient uptake or depletion of host energy reserves to fight chronic infections (3.1%, n = 5). The most massive infections (< 8760 parasites), and all cases of intestinal perforation occurred in carcasses infected by P. altmani and/or P. kenti. Mortality due to infection by Profilicollis spp. occurred more frequently among juvenile and old-adult females (chi2 = 17.479, df = 9, p = 0.045) from sand and mixed habitats in Monterey and Santa Cruz in the north of the sea otter range (chi2 = 9.84, df = 4, p = 0.045). Spatial differences in sea otter mortality coincided with the relative distributions of Profilicollis altmani, P. kenti, and P. major, and may reflect differences in sea otter diet, or differences in intensity of infection in intermediate hosts. Mortality rate due to infection by Profilicollis spp. decreased between 1998 and 2001, though differences were not significant (chi2 = 3.983, df = 3, p = 0.40), and may vary on multi-year cycles due to environmental factors such as density of definitive hosts (e.g. the surf scoter Melanitta perspicillata), or El Niño. Corynosoma enhydri did not cause significant damage to the intestine of the host, even when present in great numbers.

Two-wave longitudinal findings from the Berlin aging study: introduction to a collection of articles.

We provide background information for a collection of articles that describe two-wave longitudinal findings derived from the first intensive follow-up of participants of the Berlin Aging Study (BASE). Multidisciplinary data were collected during 1995-1996 from 206 survivors approximately 4 years after baseline assessment (1990-1993). The strengths of the initial BASE design, in terms of a focus on very old age, multidisciplinary intensive assessment, and an examination of selectivity issues, were maintained in this longitudinal extension of the study.

The process of obtaining informed patient consent.

Obtaining patients' consent for procedures and operations is not simply a question of getting them to sign a form. It is a process that enables health professionals to explain to patients what is going to be done to them. It should inform them of the risks and benefits of any proposed procedures, and of any alternatives that might be available. It demonstrates respect for patient autonomy and should help to prevent legal action against health professionals.

Encuesta bacteriológica de muestras de leche de vacas afectadas de mastitis / Bacteriological survey of representative samples of milk taken from dairy cows with mastitis

Un examen de los resultados de análisis bacteriológicos de muestras de leche procedentes de vacadas afectadas de mastitis, de cinco zonas importantes de Estados Unidos, refuerza la impresión de que la mastitis estafilocócica declina en la mayoría de las zonas. Además, la importancia de otros microorganismos, incluso los Pseudomonas aeruginosa, Escherichia coli, Klebsiella y Corynebaterium, así como los hongos y levaduras, parecer ser mayor cada vez. Se ofrecen algunas pruebas de que la significación de dichos microorganismos varía de unas regiones geográficas a otras. Puesto que el uso de bacterinas y toxoides como agentes inmunizantes ha sido alentador en algunas vacadas en que otras medidas (correción de errores en la forma de atender a las vacadas, terapia antibiótica, etc.) no habían dado resultados satisfactorios, se recomienda la inmunización como un recurso preventivo que ofrece posibilidades alentadoras para ulteriores investigaciones relativas al control de la mastitis. Las investigaciones tendientes a determinar el valor de dicha inmunización habrán de controlarse bien y podrían realizarse en vacadas que no han respondido satisfactoriamente a otras medidas(AU)

Encuesta bacteriológica de muestras de leche de vacas afectadas de mastitis / Bacteriological survey of representative samples of milk taken from dairy cows with mastitis

Un examen de los resultados de análisis bacteriológicos de muestras de leche procedentes de vacadas afectadas de mastitis, de cinco zonas importantes de Estados Unidos, refuerza la impresión de que la mastitis estafilocócica declina en la mayoría de las zonas. Además, la importancia de otros microorganismos, incluso los Pseudomonas aeruginosa, Escherichia coli, Klebsiella y Corynebaterium, así como los hongos y levaduras, parecer ser mayor cada vez. Se ofrecen algunas pruebas de que la significación de dichos microorganismos varía de unas regiones geográficas a otras. Puesto que el uso de bacterinas y toxoides como agentes inmunizantes ha sido alentador en algunas vacadas en que otras medidas (correción de errores en la forma de atender a las vacadas, terapia antibiótica, etc.) no habían dado resultados satisfactorios, se recomienda la inmunización como un recurso preventivo que ofrece posibilidades alentadoras para ulteriores investigaciones relativas al control de la mastitis. Las investigaciones tendientes a determinar el valor de dicha inmunización habrán de controlarse bien y podrían realizarse en vacadas que no han respondido satisfactoriamente a otras medidas(AU)

Publicado en inglés en The Allied Veterinarian, nov.-dic. 1960