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Quantum sensing with spin defects in diamond, such as the nitrogen-vacancy (NV) center, enables the detection of various chemical species on the nanoscale. Molecules or ions with unpaired electronic spins are typically probed by their influence on the NV center's spin relaxation. Whereas it is well-known that paramagnetic ions reduce the NV center's relaxation time ($T_1$), here we report on the opposite effect for diamagnetic ions. We demonstrate that millimolar concentrations of aqueous diamagnetic electrolyte solutions increase the $T_1$ time of near-surface NV center ensembles compared to pure water. To elucidate the underlying mechanism of this surprising effect, single and double quantum NV experiments are performed, which indicate a reduction of magnetic and electric noise in the presence of diamagnetic electrolytes. In combination with ab initio simulations, we propose that a change in the interfacial band bending due to the formation of an electric double layer leads to a stabilization of fluctuating charges at the interface of an oxidized diamond. This work not only helps to understand noise sources in quantum systems but could also broaden the application space of quantum sensors towards electrolyte sensing in cell biology, neuroscience and electrochemistry.

Understanding the sequence-dependent DNA damage formation requires probing a complete pool of sequences over a wide dose range of the damage-causing exposure. We used high throughput sequencing to simultaneously obtain the dose dependence and quantum yields for oligonucleotide damages for all possible 4096 DNA sequences with hexamer length. We exposed the DNA to ultraviolet radiation at 266 nm and doses of up to 500 absorbed photons per base. At the dimer level, our results confirm existing literature values of photodamage, whereas we now quantified the susceptibility of sequence motifs to UV irradiation up to previously inaccessible polymer lengths. This revealed the protective effect of the sequence context in preventing the formation of UV-lesions. For example, the rate to form dipyrimidine lesions is strongly reduced by nearby guanine bases. Our results provide a complete picture of the sensitivity of oligonucleotides to UV irradiation and allow us to predict their abundance in high-UV environments.

Understanding diffusion in microstructures plays a crucial role in many scientific fields, including neuroscience, cancer or energy research. While magnetic resonance (MR) methods are the gold standard for diffusion measurements, spatial encoding in MR imaging has limitations. Here, we introduce nitrogen-vacancy (NV) center based nuclear magnetic resonance (NMR) spectroscopy as a powerful tool to probe diffusion with an optical readouts. We have developed an experimental scheme combining pulsed gradient spin echo (PGSE) with optically detected NV-NMR spectroscopy, which allows for the local quantification of molecular diffusion and flow within microscopic sample volumes. We demonstrate correlated optical imaging with spatially resolved PGSE NV-NMR experiments probing anisotropic water diffusion within a model microstructure. Our optically detected PGSE NV-NMR technique opens up prospects for extending the current capabilities of investigating diffusion processes with the future potential of probing single cells, tissue microstructures, or ion mobility in thin film materials for battery applications., Comment: 37 pages, 5 figures, 2 tables

Atomic-scale magnetic field sensors based on nitrogen vacancy (NV) defects in diamonds are an exciting platform for nanoscale nuclear magnetic resonance (NMR) spectroscopy. The detection of NMR signals from a few zeptoliters to single molecules or even single nuclear spins has been demonstrated using NV-centers close to the diamond surface. However, fast molecular diffusion of sample molecules in and out of nanoscale detection volumes impedes their detection and limits current experiments to solid-state or highly viscous samples. Here, we show that restricting diffusion by confinement enables nanoscale NMR spectroscopy of liquid samples. Our approach uses metal-organic frameworks (MOF) with angstrom-sized pores on a diamond chip to trap sample molecules near the NV-centers. This enables the detection of NMR signals from a liquid sample, which would not be detectable without confinement. These results set the route for nanoscale liquid-phase NMR with high spectral resolution., Affiliations: Technical University of Munich, Walter Schottky Institute and Physics Department

Zusammenfassung Ziel Es sollte untersucht werden, ob Unterschiede im Weaning bei Langzeitbeatmung infolge einer SARS-CoV-2-Infektion bestehen. Methode Es wurden für den Zeitraum Januar bis Juli 2020 Patientendaten aus dem Weaning-Register des Institutes für Lungenforschung (ILF) ausgewertet. Hierbei wurden nur abgeschlossene Weaning-Fälle aus dem eigenen Zentrum berücksichtigt. Ergebnisse Insgesamt konnten 28 Patienten ausgewertet werden, 11 wurden wegen Langzeitbeatmung nach SARS-CoV-2-Infektion behandelt, 17 Patienten hatten keine SARS-CoV-2-Infektion. 81,2 % der SARS-CoV-2-Patienten und 76,4 % der SARS-CoV-2-negativen Patienten konnten erfolgreich von der Beatmung entwöhnt werden. Die Mortalität lag bei 18,2 % in der SARS-CoV-2-positiven Gruppe und 11,8 % in der SARS-CoV-2-negativen Gruppe. Bei den Patienten mit SARS-CoV-2-Infektion handelte es sich hauptsächlich um Männer mit kardiovaskulären Begleiterkrankungen und Raucheranamnese. Ein ARDS war hier die häufigste Ursache der akuten respiratorischen Insuffizienz. Schlussfolgerung Patienten mit Langzeitbeatmung im Rahmen einer SARS-CoV-2-Infektion können erfolgreich vom Respirator entwöhnt werden. Männliche Patienten mit kardiovaskulären Begleiterkrankungen und Raucheranamnese scheinen häufiger von einer prolongierten Entwöhnung vom Respirator betroffen zu sein.

Charge transfer has proven to be an important mechanism in DNA photochemistry. In particular, guanine (dG) plays a major role as an electron donor, but the photophysical dynamics of dG‐containing charge‐transfer states have not been extensively investigated so far. Here, we use UV pump (266 nm) and picosecond IR probe (∼5–7 μm) spectroscopy to study ultrafast dynamics in dG‐containing short oligonucleotides as a function of sequence and length. For the pure purine oligomers, we observed lifetimes for the charge‐transfer states of the order of several hundreds of picoseconds, regardless of the oligonucleotide length. In contrast, pyrimidine‐containing dinucleotides d(GT) and d(GC) show much faster relaxation dynamics in the 10 to 30 ps range. In all studied nucleotides, the charge‐transfer states are formed with an efficiency of the order of ∼50 %. These photophysical characteristics will lead to an improved understanding of DNA damage and repair processes., Studying the photophysical dynamics of dG‐containing oligonucleotides by time‐resolved IR spectroscopy showed transient absorption changes pointing to excitation decay and vibrational cooling within a few picoseconds. On the 10‐500 picosecond time range transient charge‐transfer states were identified which are efficiently formed in these oligomers. The known reactivity and the high formation yield make charge‐transfer states important promoters for secondary reactions in DNA.

ZusammenfassungDie COVID-19-Pandemie stellt derzeit weltweit eine Herausforderung dar. In Österreich konnte eine Krise innerhalb des medizinischen Versorgungssystems bisher verhindert werden. Die Behandlung von Patienten mit ambulant erworbener Pneumonie („community acquired pneumonia“, CAP), inklusive durch SARS-CoV-2-Infektionen, sollte sich auch während der Pandemie weiterhin an evidenzbasierten CAP-Leitlinien orientieren. COVID-19-spezifische Anpassungen sind jedoch sinnvoll. Die Behandlung von Patienten mit chronischen Lungenerkrankungen muss während der Pandemie angepasst werden, ist aber weiterhin zu gewährleisten.

The associated particle (AP) technique has recently been used with a high-purity germanium γ-ray spectrometer to assess its capability to improve field identification of recovered chemical warfare (CW) materiel through prompt gamma-ray neutron activation analysis (PGNAA) measurements. A particularly challenging pair of CW agents commonly found in recovered munitions are phosgene (CG) and cyanogen chloride (CK), which have two of three elements in common, i.e. chlorine and carbon, but differ in the third being either oxygen or nitrogen. The detection of both latter elements is complicated by high oxygen concentration in the field environment which interferes with the small signal produced from the chemical agents. The matter is further complicated by the precautionary field practice of overpacking recovered munitions with vermiculite in larger steel multiple round containers (MRCs), which places additional oxygen-rich material in contact with the munition while further attenuating an already weak signal emitted from the munition center. This work reports quantitative results from realistic field measurements of CG and CK simulants in mock 4.2-inch (11 cm) mortar rounds overpacked with vermiculite in a large MRC. Results obtained with the AP technique are compared to those obtained with the traditional PGNAA approach for both overpacked- and bare-munition measurements. The AP technique is shown to provide a much more confident discrimination between the two chemicals, particularly for the more challenging field-relevant overpacked measurements, where a significant gain in sensitivity to all the key elements (chlorine, carbon, nitrogen and oxygen) is achieved.

Characterization of the molecular properties of surfaces under ambient or chemically reactive conditions isa fundamental scientific challenge. Moreover, many traditional analytical techniques used for probing surfaces often lack dynamic or molecular selectivity, which limits their applicability for mechanistic and kinetic studies under realistic chemical conditions. Nuclear magnetic resonance spectroscopy (NMR) is a widely used technique and would be ideal for probing interfaces due to the molecular information it provides noninvasively. However, it lacks the sensitivity to probe the small number of spins at surfaces. Here, we use nitrogen vacancy (NV) centers in diamond as quantum sensors to optically detect nuclear magnetic resonance signals fromchemically modified aluminum oxide surfaces, prepared with atomic layer deposition (ALD). With the surfaceNV-NMR technique, we are able to monitor in real-time the formation kinetics of a self assembled monolayer (SAM) based on phosphonate anchoring chemistry to the surface. This demonstrates the capability of quan-tum sensors as a new surface-sensitive tool with sub-monolayer sensitivity for in-situ NMR analysis with theadditional advantage of a strongly reduced technical complexity.

Negatively charged boron vacancies ($V_B^-$) in hexagonal boron nitride (hBN) exhibit a broad emission spectrum due to strong electron-phonon coupling and Jahn-Teller mixing of electronic states. As such, the direct measurement of zero-phonon line (ZPL) of $V_B^-$ has remained elusive. Here, we measure the room-temperature ZPL wavelength to be $773\pm2$ nm by coupling the hBN layer to the high-Q nanobeam cavity. As the wavelength of cavity mode is tuned, we observe a pronounced intensity resonance, indicating the coupling to $V_B^-$. Our observations are consistent with the spatial redistribution of $V_B^-$ emission. Spatially resolved measurements show a clear Purcell effect maximum at the midpoint of the nanobeam, in accord with the optical field distribution of the cavity mode. Our results are in good agreement with theoretical calculations, opening the way to using $V_B^-$ as cavity spin-photon interfaces.

Small volume nuclear magnetic resonance spectroscopy (NMR) has recently made considerable progress due to rapid developments in the field of quantum sensing using nitrogen vacancy (NV) centers. These optically active defects in the diamond lattice have been used to probe unprecedented small volumes on the picoliter range with high spectral resolution. However, the NMR signal size depends strongly on both the diamond sensor's and sample's geometry. Using Monte-Carlo integration of sample spin dipole moments, the magnetic field projection along the orientation of the NV center for different geometries has been analysed. We show that the NMR signal strongly depends on the NV-center orientation with respect to the diamond surface. While the signal of currently used planar diamond sensors converges as a function of the sample volume, more optimal geometries lead to a logarithmically diverging signal. Finally, we simulate the expected signal for spherical, cylindrical and nearly-2D sample volumes, covering relevant geometries for interesting applications in NV-NMR such as single-cell biology or NV-based hyperpolarization. The results provide a guideline for NV-NMR spectroscopy of microscopic objects. Keywords: Nitrogen vacancy center, nuclear magnetic resonance, Monte-Carlo, quantum sensing, sample geometry, small volume NMR., Comment: 22 pages, 6 figures, to be published in 'Journal of Magnetic Resonance Open'

The aim of the present study was to determine the effects of selective dry cow treatment (SDCT) on udder health in Swiss dairy farms compared to a blanket dry cow treatment (BDCT). Cows with a somatic cell count (SCC) of less than 250'000 cells/ml and after BDCT in the previous dry period were selected. These animals received a SDCT in the subsequent dry period. Cows with less than 150,000 cells/ml or a negative California mastitis test (CMT) received either no treatment (group oB) or an internal teat sealant (group ZV) in all teats. Cows with more than 150,000 cells/ml or a positive CMT were treated with antibiotics and teat sealants (group ZV+AB). The SCC before and after the dry period were determined. In addition, the incidence of mastitis treatments in the dry period and the first 100 days of the following lactation as well as rates of new intramammary inflammations and healing thereof were determined. Data from 115 cows were available for evaluation. The SCC postpartum of all cows after SDCT did not differ from those after BDCT in the previous year. In the group oB the SCC was significantly higher than in the previous year. While the group ZV+AB showed a significant decrease of SCC during the dry period, the other two groups showed an increase (p0.0001). In the group oB, the proportion of mastitis treatments increased from 0% after BDCT to 28% after SDCT without any udder treatment (p0.05). Due to the increasing problem of antimicrobial resistance, SDCT is a valuable alternative to the BDCT. In the present study the antibiotic consumption could be reduced by 63%, while the udder health after SDCT did not deteriorate. If cows with low SCC are dried off without antibiotics the end of lactation, it is beneficial to protect the udder during the dry period with a teat sealant.Das Ziel der vorliegenden Studie war es, die Auswirkungen des selektiven Trockenstellens auf die Eutergesundheit in Schweizer Milchviehbetrieben im Vergleich mit der generellen antibiotischen Herangehensweise zu bestimmen. Dazu wurden Kühe ausgewählt, die mit einer Milchzellzahl von weniger als 250’000 Zellen/ml und unter antibiotischem Euterschutz in der vorherigen Trockenstehperiode trockengestellt wurden. Diese Tiere wurden in der nachfolgenden Trockenstehzeit selektiv trockengestellt. Dabei erhielten die Kühe mit weniger als 150’000 Zellen/ml oder einem negativen California-Mastitis-Test (CMT) entweder keine Behandlung (Gruppe oB) oder in alle Zitzen einen internen Zitzenversiegler (Gruppe ZV). Tiere mit mehr als 150’000 Zellen/ml oder einem positiven CMT wurden kombiniert mit Antibiotika und Zitzenversiegler (Gruppe ZV+AB) geschützt. Bestimmt wurde die Höhe der Zellzahlen vor und nach der Trockenstehzeit. Zudem wurde die Inzidenz antibiotisch behandelter Mastitiden in der Galtperiode und den ersten 100 Tagen der folgenden Laktation sowie die Neuinfektions- und Heilungsrate ermittelt. Daten von 115 Kühen standen für die Auswertung zur Verfügung. Die Zellzahlen aller Kühe nach der Abkalbung unterschieden sich nach dem selektiven nicht von denen nach generell antibiotischem Trockenstellen im Vorjahr. Jedoch war die Zellzahl in der Gruppe oB signifikant höher als im Vorjahr. Während die Gruppe ZV+AB eine signifikante Abnahme der Zellzahlen im Verlauf der Trockenstehperiode zeigte, kam es bei den beiden anderen Gruppen zu einem Anstieg (p0.0001). In der Gruppe oB stieg der Anteil an behandelten Mastitiden von 0% nach antibiotischer Trocken­stellung auf 28% nach dem Trockenstellen ohne Eu­terschutz (p0.05). Aufgrund der heutigen Resistenzproblematik ist das selektive Trockenstellen eine wertvolle Alternative zur generell antibiotischen Herangehensweise. In der vorliegenden Untersuchung konnte der Antibiotikaverbrauch um 63% reduziert werden, während sich der Eutergesundheitszustand, von allen selektiv trockengestellten Tieren zusammen betrachtet, nicht verschlechtert hat. Erhalten Kühe mit niedrigen Zellzahlen am Ende der Laktation keinen antibiotischen Trockensteller, ist es jedoch sinnvoll, das Euter während der Trockenstehperiode mittels Zitzenversiegler zu schützen.Le but de la présente étude était de déterminer les effets du tarissement sélectif sur la santé de la mamelle dans des exploitations laitières suisses par rapport à un tarissement systématique avec antibiotiques de couverture. Des vaches dont le nombre de cellules somatiques (CCS) était inférieur à 250 000 cellules/ml et qui avaient été taries avec une protection antibiotique lors de la lactation précédente ont été sélectionnées. Ces animaux ont été taris de façon sélective à la lactation suivante. Les vaches avec moins de 150 000 cellules/ml ou un test de mammite de Californie (CMT) négatif n’ont reçu aucun traitement (groupe oB) ou un obturateur de trayon interne dans tous les trayons (groupe ZV). Les vaches avec plus de 150 000 cellules/ml ou une CMT positive ont été traitées avec des antibiotiques et des obturateurs de trayons (groupe ZV + AB). Les CCS avant et après la période de tarissement ont été déterminés. En outre, l’incidence de traitements de mammite pendant la période de tarissement et les 100 premiers jours de la lactation suivante, ainsi que les taux de nouvelles inflammations mammaires et de leur guérison ont été relevées. Les données de 115 vaches étaient disponibles pour évaluation. Le nombre de cellules post-partum de toutes les vaches après tarissement sélectif ne différait pas de celui après utilisation systématique de tarisseurs l’année précédente. Dans le groupe oB, le CCS était nettement plus élevé que l’année précédente. Alors que le groupe ZV + AB a montré une diminution significative de la SCC pendant la période sèche, les deux autres groupes ont présenté une augmentation (p.Lo scopo del presente studio era di determinare gli effetti della terapia selettiva alla messa in asciutta (SDCT) sulla salute della mammella nelle aziende con mucche da latte svizzere rispetto alla terapia sistematica alla messa in asciutta con antibiotici (BDCT). A tal fine, le mucche che sono state selezionate avevano un conteggio delle cellule somatiche inferiore a 250 000 cellule/ml ed erano state messe in BDCT per proteggere la mammella. Questi animali nel periodo di asciutta seguente erano stati messi in SDCT. Alle mucche che avevano meno di 150 000 cellule/ml o sono risultate negative al California Mastitis Test (CMT) è stato somministrato nessun trattamento (gruppo oB) o ogni capezzolo è stato sigillato con un sigillante per capezzoli interno (gruppo ZV). Gli animali con oltre 150 000 cellule/ml o risultati positivi al CMT sono stati protetti con antibiotici e un sigillante per capezzoli (gruppo ZV + AB). Si è determinato il numero di cellule prima e dopo il periodo di asciutta. Inoltre è stata determinata l’incidenza del trattamento antibiotico sulla mastite durante il periodo di asciutta e nei primi 100 giorni della successiva lattazione, il tasso di nuove infezioni e quello di cura. I dati di 115 mucche erano disponibili per la valutazione. La conta delle cellule di tutte le mucche dopo il parto non differiva sia per le mucche dopo SDCT che per quelle dopo BDCT. Tuttavia, il numero di cellule nel gruppo oB era significativamente più alto rispetto all’anno precedente. Mentre il gruppo ZV+AB ha dimostrato una significativa riduzione del numero di cellule durante il periodo di asciutta, gli altri due gruppi avevano mostrato un aumento (p.

With the emergence of a new virus and the associated pandemic, the ICU started to see a brand new kind of patient with severe ARD. As with any disease, sometimes the discontinuation of mechanical ventilation for any reason can be difficult. As a center specializing in weaning patients after prolonged mechanical ventilation, we wanted to compare our results with weaning patients who had prolonged mechanical ventilation for other reasons than those of patients who had prolonged mechanical ventilation due to SARS-CoV-2 infection. We obtained our data from WeanNet register, the weaning register of the German Institute for Lung Research (ILF). In our analysis, we included only patient data from January until July 2020, which was recorded in our in-house study files. Our analysis included data on 28 patients; 11 were treated with prolonged mechanical ventilation due to SARS-CoV-2 pneumonia, 17 had no SARS-CoV-2 infection. 81.2 % of SARS-CoV-2 patients were successfully weaned from invasive ventilator therapy compared to 76.4 % of patients without SARS-CoV-2. Mortality in the SARS-CoV-2 group was 18.2 % compared to 11.8 % in the other group. Patients with SARS-CoV-2 infections were predominantly males with preexisting cardiovascular disease or a history of nicotine abuse. ARDS was the most common cause of respiratory failure which led to primary intubation. Even though we were only able to analyze a small number of patient histories due to the novelty of the disease, we were able to show that patients with prolonged mechanical ventilation after SARS-CoV-2 infection can be equally successfully weaned compared to patients with prolonged mechanical ventilation due to other diseases. Risk factors for prolonged mechanical ventilation after a severe case of SARS-CoV-2 infection seemed to be male gender, nicotine abuse and cardiovascular disease.ZIEL: Es sollte untersucht werden, ob Unterschiede im Weaning bei Langzeitbeatmung infolge einer SARS-CoV-2-Infektion bestehen. Es wurden für den Zeitraum Januar bis Juli 2020 Patientendaten aus dem Weaning-Register des Institutes für Lungenforschung (ILF) ausgewertet. Hierbei wurden nur abgeschlossene Weaning-Fälle aus dem eigenen Zentrum berücksichtigt. Insgesamt konnten 28 Patienten ausgewertet werden, 11 wurden wegen Langzeitbeatmung nach SARS-CoV-2-Infektion behandelt, 17 Patienten hatten keine SARS-CoV-2-Infektion. 81,2 % der SARS-CoV-2-Patienten und 76,4 % der SARS-CoV-2-negativen Patienten konnten erfolgreich von der Beatmung entwöhnt werden. Die Mortalität lag bei 18,2 % in der SARS-CoV-2-positiven Gruppe und 11,8 % in der SARS-CoV-2-negativen Gruppe. Bei den Patienten mit SARS-CoV-2-Infektion handelte es sich hauptsächlich um Männer mit kardiovaskulären Begleiterkrankungen und Raucheranamnese. Ein ARDS war hier die häufigste Ursache der akuten respiratorischen Insuffizienz. Patienten mit Langzeitbeatmung im Rahmen einer SARS-CoV-2-Infektion können erfolgreich vom Respirator entwöhnt werden. Männliche Patienten mit kardiovaskulären Begleiterkrankungen und Raucheranamnese scheinen häufiger von einer prolongierten Entwöhnung vom Respirator betroffen zu sein.

This paper uses the logarithmic mean Divisia index (LMDI) approach to decomposition analysis to identify the factors that influence changes in carbon dioxide (CO2) emissions in the United States. The LMDI approach decomposes CO2 emissions into specific determinants. The data set includes the 50 states plus the District of Columbia from 1998 – 2018. The five factors that influence the change in CO2 emissions include the emissions per unit of fossil fuel consumption, share of fossil fuels in total energy consumption, energy intensity, GDP per capita, and population. The results indicate that, during the 20-year period, CO2 emissions declined in 36 states plus the District of Columbia. The reduction in energy intensity served as the most important factor in the change of CO2 emissions, offsetting 63 percent of the effects of per capita GDP and population. From the perspective of climate change, the importance of a change in energy intensity demonstrates the effectiveness of a decrease in primary energy consumption per unit of GDP. &nbsp

High-resolution sensing of weak signals is implemented by means of an integrated diamond---nuclear-magnetic-resonance technique

The beta-decay of Zn-81 to the neutron magic N = 50 nucleus Ga-81, with only three valence protons with respect to Ni-78, was investigated. The study was performed at the ISOLDE facility at CERN by means of gamma spectroscopy. The 81Zn half-life was determined to be T-1/2 = 290(4) ms while the beta-delayed neutron emission probability was measured as P-n = 23(4)%. The analysis of the beta-gated gamma-ray singles and gamma-gamma coincidences from the decay of Zn-81 provides 47 new levels and 70 new transitions in Ga-81. The beta(-)n decay of Zn-81 was observed and a new decay scheme into the odd-odd Ga-80 nucleus was established. The half-lives of the first and second excited states of Ga-81 were measured via the fast-timing method using LaBr3(Ce) detectors. The level scheme and transition rates are compared to large-scale shell-model calculations. The low-lying structure of (81)Gais interpreted in terms of the coupling of the three valence protons outside the doubly magic Ni-78 core.

Die COVID-19-Pandemie stellt derzeit weltweit eine Herausforderung dar. In Österreich konnte eine Krise innerhalb des medizinischen Versorgungssystems bisher verhindert werden. Die Behandlung von Patienten mit ambulant erworbener Pneumonie („community acquired pneumonia“, CAP), inklusive durch SARS-CoV-2-Infektionen, sollte sich auch während der Pandemie weiterhin an evidenzbasierten CAP-Leitlinien orientieren. COVID-19-spezifische Anpassungen sind jedoch sinnvoll. Die Behandlung von Patienten mit chronischen Lungenerkrankungen muss während der Pandemie angepasst werden, ist aber weiterhin zu gewährleisten.

Endocrine-active substances can adversely impact the aquatic ecosystems. A special emphasis is laid, among others, on the effects of estrogens and estrogen mimicking compounds. Effect-based screening methods like in vitro bioassays are suitable tools to detect and quantify endocrine activities of known and unknown mixtures. This study describes the validation of the Arxula-Yeast Estrogen Screen (A-YES®) assay, an effect-based method for the detection of the estrogenic potential of water and waste water. This reporter gene assay, provided in ready to use format, is based on the activation of the human estrogen receptor alpha. The user-friendly A-YES® enables inexperienced operators to rapidly become competent with the assay. Fourteen laboratories from four countries with different training levels analyzed 17β-estradiol equivalent concentrations (EEQ) in spiked and unspiked waste water effluent and surface water samples, in waste water influent and spiked salt water samples and in a mixture of three bisphenols. The limit of detection (LOD) for untreated samples was 1.8 ng/L 17β-estradiol (E2). Relative repeatability and reproducibility standard deviation for samples with EEQ above the LOD (mean EEQ values between 6.3 and 20.4 ng/L) ranged from 7.5 to 21.4% and 16.6 to 28.0%, respectively. Precision results are comparable to other frequently used analytical methods for estrogens. The A-YES® has been demonstrated to be an accurate, precise and robust bioassay. The results have been included in the ISO draft standard. The assay was shown to be applicable for testing of typical waste water influent, effluent and saline water. Other studies have shown that the assay can be used with enriched samples, which lower the LOD to the pg/L range. The validation of the A-YES® and the development of a corresponding international standard constitute a step further towards harmonized and reliable bioassays for the effect-based analysis of estrogens and estrogen-like compounds in water samples.

An extensive, model-independent analysis of the nature of triaxial deformation in $^{76}$Ge, a candidate for neutrinoless double-beta ($0\nu\beta\beta$) decay, was carried out following multi-step Coulomb excitation. Shape parameters deduced on the basis of a rotational-invariant sum-rule analysis provided considerable insight into the underlying collectivity of the ground-state and $\gamma$ bands. Both sequences were determined to be characterized by the same $\beta$ and $\gamma$ deformation parameter values. In addition, compelling evidence for low-spin, rigid triaxial deformation in $^{76}$Ge was obtained for the first time from the analysis of the statistical fluctuations of the quadrupole asymmetry deduced from the measured $E2$ matrix elements. These newly determined shape parameters are important input and constraints for calculations aimed at providing, with suitable accuracy, the nuclear matrix elements relevant to $0\nu\beta\beta$., Comment: 6 pages, 5 figures

Nitrogen-vacancy (NV) quantum defects in diamond are sensitive detectors of magnetic fields. Due to their atomic size and optical readout capability, they have been used for magnetic resonance spectroscopy of nanoscale samples on diamond surfaces. Here we present a protocol for fabricating NV-diamond chips and for constructing and operating a simple, low-cost quantum diamond spectrometer for performing nuclear magnetic resonance (NMR) and electron spin resonance (ESR) spectroscopy in nanoscale volumes. The instrument is based on a commercially-available diamond chip, with an ion-implanted NV-ensemble at a depth of ~ 10 nm below the diamond surface. The spectrometer operates at low magnetic fields (~ 300 G) and requires standard optical and microwave components for NV spin preparation, manipulation and readout. We demonstrate the utility of this device for nanoscale proton and fluorine NMR spectroscopy, as well as for the detection of transition metals via ESR noise spectroscopy. We estimate that the full protocol requires 2-3 months to implement, depending on the availability of equipment, diamond substrates, and user experience.

Rapid shape evolutions near A = 100 are now the focus of much attention in nuclear science. Much of the recent work has been centered on isotopes with Z

Ecotoxicological screening of surface waters can involve multiple analyses using multiple bioassay and chemical analytical methods that require enriched samples to reach low concentrations. Such broad screening of the same sample necessitates sufficient sample volume-typically several liters-to produce a sufficient amount of enriched sample. Often, this is achieved by performing parallel solid-phase extractions (SPE) where extracts are combined into a pool-this is a laborious process. In this study, we first validated our existing SPE method for the chemical recovery of an extended set of compounds. We spiked four estrogenic compounds and 11 herbicides to samples from independent rivers (1 L) and wastewater treatment plant effluents (0.5 L). Then, we investigated the effect of increased sample loading of the SPE cartridges on both chemical and biological recoveries by comparing the validated volumes with four times larger sample volumes (i.e., 4 L river water and 2 L effluent). Samples were analyzed by LC-MS/MS and three bioassays: an estrogen receptor transactivation assay (ERα-CALUX), the combined algae test, and a bacterial bioluminescence inhibition assay. Our existing SPE method was found to be suitable for enriching the extended set of estrogens and herbicides in river water and effluents with near to perfect chemical recoveries (~ 100%), except for the herbicide metribuzin (46 ± 19%). In the large volume river and effluent samples, the biological activities and concentrations of the spiked compounds were between 87 and 104% of those measured with the lower sample loading, which is adequate. In addition, the ratio between the large and original volume SPE method for the non-target endpoint (bacterial bioluminescence inhibition) was acceptable (on average 82 ± 9%). Results indicate that our current water extraction method can be applied to up to four times larger sample volumes, resulting in four times more extract volumes, without significant reductions in recoveries for the tested estrogens and herbicides. Graphical abstract ᅟ.

Nuclear magnetic resonance (NMR) spectroscopy is a widely used tool for chemical analysis and molecular structure identification. Because it typically relies on the weak magnetic fields produced by a small thermal nuclear spin polarization, NMR suffers from poor molecule-number sensitivity compared to other analytical techniques. Recently, a new class of NMR sensors based on optically probed nitrogen-vacancy (NV) quantum defects in diamond have allowed molecular spectroscopy from sample volumes several orders of magnitude smaller than the most sensitive inductive detectors. To date, however, NV NMR spectrometers have only been able to observe signals from pure, highly concentrated samples. To overcome this limitation, we introduce a technique that combines picoliter-scale NV NMR with fully integrated Overhauser dynamic nuclear polarization to perform high-resolution spectroscopy on a variety of small molecules in dilute solution, with femtomole sensitivity. Our technique advances the state of the art of mass-limited NMR spectroscopy, opening the door to new applications at the picoliter scale in drug and natural-product discovery, catalysis research, and single-cell studies.

The decay of electronically excited states of thymine (Thy) and thymidine 5′-monophosphate (TMP) was studied by time-resolved UV/vis and IR spectroscopy. In addition to the well-established ultrafast internal conversion to the ground state, a so far unidentified UV-induced species is observed. In D2O, this species decays with a time constant of 300 ps for thymine and of 1 ns for TMP. The species coexists with the lowest triplet state and is formed with a comparably high quantum yield of about 10% independent of the solvent. The experimentally determined spectral signatures are discussed in the light of quantum chemical calculations of the singlet and triplet excited states of thymine.

UV-induced formation of the cyclobutane pyrimidine dimer (CPD) lesion is investigated by stationary and time-resolved photosensitization experiments. The photosensitizer 2'-methoxyacetophenone with high intersystem crossing efficiency and large absorption cross-section in the UV-A range was used. A diffusion controlled reaction model is presented. Time-resolved experiments confirmed the validity of the reaction model and provided information on the dynamics of the triplet sensitization process. With a series of concentration dependent stationary illumination experiments, we determined the quantum efficiency for CPD formation from the triplet state of the thymine dinucleotide TpT to be 4 ± 0.2%.

Quantum systems that consist of solid-state electronic spins can be sensitive detectors of nuclear magnetic resonance (NMR) signals, particularly from very small samples. For example, nitrogen-vacancy centres in diamond have been used to record NMR signals from nanometre-scale samples, with sensitivity sufficient to detect the magnetic field produced by a single protein. However, the best reported spectral resolution for NMR of molecules using nitrogen-vacancy centres is about 100 hertz. This is insufficient to resolve the key spectral identifiers of molecular structure that are critical to NMR applications in chemistry, structural biology and materials research, such as scalar couplings (which require a resolution of less than ten hertz) and small chemical shifts (which require a resolution of around one part per million of the nuclear Larmor frequency). Conventional, inductively detected NMR can provide the necessary high spectral resolution, but its limited sensitivity typically requires millimetre-scale samples, precluding applications that involve smaller samples, such as picolitre-volume chemical analysis or correlated optical and NMR microscopy. Here we demonstrate a measurement technique that uses a solid-state spin sensor (a magnetometer) consisting of an ensemble of nitrogen-vacancy centres in combination with a narrowband synchronized readout protocol to obtain NMR spectral resolution of about one hertz. We use this technique to observe NMR scalar couplings in a micrometre-scale sample volume of approximately ten picolitres. We also use the ensemble of nitrogen-vacancy centres to apply NMR to thermally polarized nuclear spins and resolve chemical-shift spectra from small molecules. Our technique enables analytical NMR spectroscopy at the scale of single cells.

International audience; The 12C+12C fusion reaction is one of the most important for nuclear astrophysics since it determines the carbon ignition in stellar environments. Two experiments which make use of the gamma-particle coincidence technique to measure the 12C+12C S-factors at deep sub barrier energies are discussed. Results are presented showing a decrease of the S-factor below Ec.m. = 3 MeV.

The γ - summing technique was successfully implemented for the first time in inverse kinematics using the NSCL Summing NaI(Tl) detector at the Nuclear Science Laboratory of the University of Notre Dame. This new method offers a way to measure (p,γ) and (α,γ) reactions on unstable nuclei, which are critical for an improved understanding of nucleosynthesis. As a proof of principle, the well-known resonances at E c . m . = 956 keV in the p(27Al,γ)28Si reaction and at E c . m . = 1400 keV in the p(58Ni,γ)59Cu reaction were measured and their resonance strengths were deduced. The values of the present work agree well with the reported literature values, demonstrating the viability of the technique.

The decay of triplet states and the formation of cyclobutane pyrimidine dimers (CPDs) after UV excitation of the all-thymine oligomer (dT)18 and the locked dinucleotide TLpTL were studied by nanosecond IR spectroscopy. IR marker bands characteristic for the CPD lesion and the triplet state were observed from ∼1 ns (time resolution of the setup) onward. The amplitudes of the CPD marker bands remain constant throughout the time range covered (up to 10 μs). The triplet decays with a time constant of ∼10 ns presumably via a biradical intermediate (lifetime ∼60 ns). This biradical has often been invoked as an intermediate for CPD formation via the triplet channel. The present results lend strong support to the existence of this intermediate, yet there is no indication that its decay contributes significantly to CPD formation.

High demand for nuclear reaction cross-section measurements relevant for astrophysical processes requires the development of new experimental techniques that allow for investigation of, often very low, cross-sections. For this purpose, a new 4 π Summing NaI(Tl) detector (SuN) has been constructed, which is an 8-fold segmented NaI(Tl) barrel read by 24 photomultipliers. The design of the detector will be presented and detailed results of the commissioning experiments utilizing standard calibration sources and known Al 27 ( p , γ ) Si 28 resonances will be discussed.

In rare earth compounds with localized 4f states the observation of bound 4f-hole-5d-electron states, excitons, is questionable. On the other hand the same compounds exhibit p–d excitons, which are derived from itinerant bands. In rare earth compounds, which exhibit intermediate valence, 4f–5d hybridization produces a narrow, several 10 meV wide 4f band. Now 4f–5d excitons are possible and have been observed in TmSe 0.45 Te 0.55 and similar compositions. The special band structure of these materials permits an enormous amount of excitons (≈10 21 cm −3 ), which condense in a first order transition at low temperatures and high pressure. This static and immense concentration of excitons dominates the heat conductivity and the thermal diffusivity and even exhibits the phenomenon of superfluidity in a solid. The measured specific heat shows that phonons couple to these excitons forming exciton polarons.

The breakup reaction $^{9}\mathrm{Be}(^{4}\mathrm{He},3\ensuremath{\alpha})\mathit{n}$ was measured using an array of four double-sided silicon strip detectors at beam energies of 22 and 26 MeV. Excited states in $^{9}\mathrm{Be}$ up to 8 MeV were populated and reconstructed through measurements of the charged reaction products. Evidence is given for a state in $^{9}\mathrm{Be}$ at $3.{82}_{\text{-0.09}}^{\text{+0.08}}$ MeV with $\mathrm{\ensuremath{\Gamma}}={1240}_{\text{-90}}^{\text{+270}}$ keV. This is consistent with two recent measurements of a state with similar properties in the mirror nucleus $^{9}\mathrm{B}$. An analysis of the reduced widths ($^{8}\mathrm{Be}_{\mathrm{g}.\mathrm{s}.}$ channel) of this state along with the proposed mirror state has led to a firm limit of $J\ensuremath{\le}7/2$ and a tentative assignment of ${J}^{\ensuremath{\pi}}=1/{2}^{\ensuremath{-}}$ or $3/{2}^{\ensuremath{-}}$.

A particle- γ coincidence technique has been used to measure the fusion cross-section in the system 12C+12C at low beam energies. Based on these results, it should be possible to measure this important fusion cross-section down to the 10 pb level within a week-long run.

Annually since 1989, biannually since 1994 the sites of the Swiss nuclear facilities (4 power plant sites, a nuclear research institute and a waste storage facility) are surveyed flying the same survey lines by airborne gamma ray spectrometry. The equipment and the data processing software used for those surveys was built and developed at the Institute of Geophysics, ETH Zurich. For mapping the ground radiation around the nuclear facilities a pixel representation and a modified Spectrum Dose Index (SDI) method is used. In the search for long-term trends the local dose-rates are calculated first and in turn the net dose rates over the time span 1992–2010. So far no significant change in the radiation levels was detected over the last 18 years outside of the fenced sites of the nuclear facilities, except for the operation of an industrial radiation facility in 1995.