A pulsed source of continuous variable polarization entanglement

We have experimentally demonstrated polarization entanglement using continuous variables in an ultra-short pulsed laser system at telecommunication wavelengths. Exploiting the Kerr-nonlinearity of a glass fibre we generated a polarization squeezed pulse with S2 the only non-zero Stokes parameter thus S1 and S3 being the conjugate pair. Polarization entanglement was generated by interference of the polarization squeezed field with a vacuum on a 50:50 beam splitter. The two resultant beams exhibit strong quantum noise correlations in S1 and S3. The sum noise signal of S3 was at the respective shot noise level and the difference noise signal of S1 fell 2.9dB below this value

ОПРЕДЕЛЕНИЕ СТРУКТУРЫ ПРИМЕСЕЙ В ТРИЭТИЛЕНГЛИКОЛЕ МЕТОДАМИ ЯМР И ВЭЖХ-МС/МС ВЫСОКОГО РАЗРЕШЕНИЯ

The process of natural gas drying leads to accumulation of unstudied organic impurities in the used absorbent solutions. These impurities reduce the drying capacity of triethylene glycol. In order to increase the effectiveness of installations for drying natural gas it is necessary to purify triethylene glycol from the accumulated impurities. The absence of information on the structure and properties of these impurities considerably complicates the purification of the absorbent solutions. In this study the structures of impurities accumulated in triethylene glycol were determined by NMR and high resolution mass-spectrometry coupled with chromatography (HPLC-MS/MS). The obtained results will enable to improve the existing methods for the purification of the working solutions of the absorbent.В процессе абсорбционной осушки природного газа в используемых растворах абсорбентах накапливаются неизученные органические примеси, которые снижают осушающую способность триэтиленгликоля. Для повышения эффективности функционирования установок осушки природного газа необходимо периодически очищать триэтиленгликоль от накопливающихся загрязнителей. Отсутствие информации о структуре и свойствах этих примесей существенно усложняет процедуру очистки рабочих растворов абсорбента. В работе были установлены структуры соединений, накапливающихся в триэтиленгликоле, методами ЯМР и ВЭЖХ-МС/МС высокого разрешения. Полученные результаты позволят усовершенствовать существующие способы очистки рабочих растворов абсорбента

Simple Gd³⁺-Neu5: N Ac complexation results in NMR chemical shift asymmetries of structurally equivalent complex-type N -glycan branches

© The Royal Society of Chemistry 2017. In the present Communication, we propose a quite simple but previously overlooked approach for conveniently analyzing, assigning, and extracting sialic acid-containing N-glycan structures using high-resolution NMR spectroscopy without pre-installing metal chelators.Paramagnetic metals, such as Gd 3+ , appear to bind to the carboxyl groups of N-acetylneuraminic acid when introduced at room temperature, leading to the measurement of nonequivalent proton and carbon NMR spectral signals among otherwise "identical" glycan branched structures

Применение методов гх-мс и вэжх-мс/мс для анализа примесей в триэтиленгликоле, накапливающихся в процессе осушки природного газа

Natural gas conversion is a complex dynamic process in need of constant monitoring. Improvement and automation of its steps is of great importance for upgrading quality and reducing cost. Conversion optimisation requires application of modern analytical instrumentation. Current analytical technics are time consuming, lack versatility and hardly prone to automation. In this work, development of comprehensive analytical procedure for control of triglycol contaminants accumulating during gas drying step is discussed. This procedure is based on LC-MS/MS, GCMS and multiparametric statistical analysis. The analytical procedure presented in this work is rapid and allows determining a wide range of triglycol contaminants.Переработка природного газа - сложный динамичный процесс, требующий постоянного мониторинга. Совершенствование и автоматизация отдельных его этапов является ключевой задачей как для повышения качества конечного продукта, так и для снижения его себестоимости. Применение аналитических инструментов к этапам переработки газа необходимо при оптимизации и мониторинге данных процессов. Существующие аналитические методики являются устаревшими, не удовлетворяют требованиям к универсальности, скорости, не подлежат автоматизации. В работе представлены этапы разработки современного комплексного аналитического подхода, предназначенного для анализа примесей в триэтиленгликоле, накапливающихся в процессе осушки природного газа. В основу работы положены методы ВЭЖХ-МС/МС и ГХ-МС, а также методы многопараметрической статистики, используемые при обработке полученных результатов. Разработанный подход отвечает современным требованиям к аналитическим методикам, является экспрессным, и позволяет анализировать одновременно широкий диапазон соединений, отличающихся по физико-химическим свойствам

Polarization quantum properties in type-II Optical Parametric Oscillator below threshold

We study the far field spatial distribution of the quantum fluctuations in the transverse profile of the output light beam generated by a type II Optical Parametric Oscillator below threshold, including the effects of transverse walk-off. We study how quadrature field correlations depend on the polarization. We find spatial EPR entanglement in quadrature-polarization components: For the far field points not affected by walk-off there is almost complete noise suppression in the proper quadratures difference of any orthogonal polarization components. We show the entanglement of the state of symmetric intense, or macroscopic, spatial light modes. We also investigate nonclassical polarization properties in terms of the Stokes operators. We find perfect correlations in all Stokes parameters measured in opposite far field points in the direction orthogonal to the walk-off, while locally the field is unpolarized and we find no polarization squeezing.Comment: 16 pages, 18 figure

Advancing Age Alters the Contribution of Calcium Release From Smooth Endoplasmic Reticulum Stores in Superior Cervical Ganglion Cells

In superior cervical ganglion (SCG) neurons calcium-induced calcium release (CICR), mediated by ryanodine receptors (RyRs), contributes to stimulation-evoked intracellular calcium ([Ca2+]i) transients. Hypothesis: The contribution of CICR to electrical field stimulation (EFS)–evoked [Ca2+]i transients in SCG cells declines with senescence and may be partially recovered in the presence of caffeine. We measured EFS-evoked [Ca2+]i transients in isolated fura-2–loaded SCG cells from Fischer-344 rats aged 6, 12, and 24 months with either the RyR antagonist ryanodine to block the contribution of CICR to [Ca2+]i transients or caffeine to sensitize CICR to EFS. EFS-evoked [Ca2+]i transients increased from 6 to 12 months and declined at 24 months and ryanodine decreased [Ca2+]i transients in SCG cells from 6- and 12-month-old animals only. Caffeine significantly increased EFS-evoked [Ca2+]i transients in all age groups. These data suggest that CICR declines with senescence and residual CICR function may be reclaimed in senescent cells with caffeine

Polarization squeezing and continuous-variable polarization entanglement

The Stokes-parameter operators and the associated Poincare sphere, which describe the quantum-optical polarization properties of light, are defined and their basic properties are reviewed. The general features of the Stokes operators are illustrated by evaluation of their means and variances for a range of simple polarization states. Some of the examples show polarization squeezing, in which the variances of one or more Stokes parameters are smaller than the coherent-state value. The main object of the paper is the application of these concepts to bright squeezed light. It is shown that a light beam formed by interference of two orthogonally-polarized quadrature-squeezed beams exhibits squeezing in some of the Stokes parameters. Passage of such a primary polarization-squeezed beam through suitable optical components generates a pair of polarization-entangled light beams with the nature of a two-mode squeezed state. The use of pairs of primary polarization-squeezed light beams leads to substantially increased entanglement and to the generation of EPR-entangled light beams. The important advantage of these nonclassical polarization states for quantum communication is the possibility of experimentally determining all of the relevant conjugate variables of both squeezed and entangled fields using only linear optical elements followed by direct detection.Comment: 27 pages, including 10 figure

The PHENIX Experiment at RHIC

The physics emphases of the PHENIX collaboration and the design and current status of the PHENIX detector are discussed. The plan of the collaboration for making the most effective use of the available luminosity in the first years of RHIC operation is also presented.Comment: 5 pages, 1 figure. Further details of the PHENIX physics program available at http://www.rhic.bnl.gov/phenix

Феномен “несоответствия” режимов T2 и Т2-FLAIR как нейровизулизационный биомаркер генетического профиля анапластических астроцитом

The aim of the study was to assess T2/T2-FLAIR mismatch phenomenon as a predictor of particular genetic profile in the anaplastic astrocytoma group, including those tumors demonstrating contrast enhancement on MRI.Materials and methods. It is a retrospective study. All MR images were anonymized.MRI analysis. We studied 242 MRIs of patients with anaplastic astrocytomas (AA) and anaplastic oligodendrogliomas (AO) who were surgically treated at Burdenko Neurosurgery Center from 01.01.2017 to 31.12.2019. Among 242 patients we identified 23 (9.5%) whose MRI fulfilled the criteria for T2/FLAIR mismatch sign. The images were studied by 3 experienced neuroradiologist and patients were allocated to the T2/FLAIR mismatch group only upon consensus. Readers evaluated T2WI and FLAIR sequences of each MRI examination. They determined thr following characteristics of the tumours, using a binary scoring system for each: 1) presence or absence of homogeneous signal intensity on T2WI; 2) presence or absence of complete/near-complete hyperintence signal on T2WI, and relatively hypointence on FLAIR except for a hyperintense peripheral rim; 3) margins of lesion sharp or indistinct; 4) presence or absence of peritumoral edema. Discordant results were resolved by consensus with more experienced neuroradiologist.Histological examination and molecular markers. Histological examination was carried out by 2 qua lified pathologists after staining the preparations with hematoxylin and eosin and calculating the index of proliferative activity. The final diagnosis was established on the basis of a combination of morphological and molecular genetic studies. The material for the study was 242 biopsies from patients operated on at Burdenko Neurosurgery Center with anaplastic astrocytomas and anaplastic oligodendrogliomas WHO Grade III, fixed in 10% neutral formalin and embedded in Histomax (Leica) paraffin. Among 23 patients with T2 / FLAIR mismatch in 4 archival cases was performed an immunohistochemical study with Anti-IDH1 R132H (clone H09) (dianova) antibodies to establish the mutational status of the IDH-1 gene; in 19 remaining cases the IDH1 R132H mutation was studied by real-time PCR using self-selected primers and probes. One of the samples showed the wild type IDH1 R132H and it was further investigated by Sanger sequencing to determine the mutational status of the IDH1 and IDH2 genes using direct primers.Determination of 1p / 19q co-deletion was performed by in situ fluorescence hybridization using a ZytoLight Glioma 1p / 19q Probe Set (ZytoVision).Study results. T2/T2-FLAIR mismatch sign was found in 23 patients with AA, in 8 cases tumors demonstrated contrast enhancement, including 3 of them with substantial enhancement. The mean age in the T2/T2-FLAIR mismatch group was lower than in the main group (34 vs. 42.7 years), as well as percentage of patients with contrastenhancing tumors (36.4% vs. 55.8%). The proportion of tumors with substantial contrast enhancement was similar in both groups (37.5% vs. 46.7%).DiscussionS.H. Patel et al. in their pioneer paper demonstrated 12% frequency of T2/FLAIR mismatch sign in the experimental group (125 patients) and 17% in validation group (60 patients). M.P.G. Broen et al. present with a higher rate of the sign – 25%. S. Deguchi et al. have demonstrated even higher frequency of T2/FLAIR mismatch among IDHmutant grade II astrocytomas -45%. Our results revealed 9.5% rate of this sign.The first article declaring less than 100% specificity of T2/FLAIR mismatch sign, after great success and acknowledgement of this predictive diagnostic method, was published by T.A. Juratli et al. 2019: the sign was observed in 73% of patients (versus 12% in Patel’s group). Herewith, 29% of patients with T2/FLAIR mismatch sign demonstrated both IDH-1 mutation and 1p/19q co-deletion. The reason for this phenomenon were less strict inclusion criteria in Juratli’s study. Moreover, authors did not specify the number of patients with contrast-enhancing tumors, although according to R. Jain et al., all these tumors must be excluded from the study. It is noteworthy, that even with these non-strict inclusion criteria, T2/FLAIR mismatch sign has demonstrated 100% predictive value for IDH-1 mutation in Jurartli’s study (none of the patients presented with IDH-wild type tumour). In the meta-analysis performed by Goyal et al. 2019, based on several T2/FLAIR mismatch studies with 746 patients, authors demonstrated high specificity (98.5%) and low sensitivity (33.7%) of this sign for detecting IDH-1+ and 1p/19q- cooperation. The main conclusion of this paper is that T2/FLAIR mismatch sign has high specificity and low sensitivity for detecting IDH-1 mutation, but not 1p/19q co-deletion, although there might be exceptions from this rule.Recent studies devoted to the T2/FLAIR mismatch sign included mostly grade II gliomas and a small amount of AA and AO, emphasizing that those tumors did not demonstrate contrast enhancement M.P.G. Broen, S.H. Patel. Moreover, this characteristic is referred as a necessary qualification for T2/FLAIR mismatch sign, since contrastenhancing parts of the tumor may overlap area of interest and confound MRI signal in other sequences.Results of our study convincingly demonstrate possibility of T2/FLAIR mismatch sign in grade III gliomas with contrast enhancement. We observed this phenomenon in 8 cases out of 22 (36.4%). Moreover, among those8 patients, 3 presented with intensive contrast enhancement. Comparing main group with control one, we revealed, that mean age in the group with T2/FLAIR mismatch sign was lower (34 vs. 42.7). and among 8 patients with contrast enhancement only 1 was older than 40 years. Tumors from the main group demonstrated contrast enhancement significantly on a more frequent basis (55.8% vs. 36.4%), meanwhile rate of intensive contrast enhancement was similar (46.7% vs. 37.5%). Thus, we demonstrated correlation between tumour grade and contrast enhancement and T2/FLAIR mismatch sign.Earlier studies made attempts to predict tumor mutational status upon MRI: for instance, frontal lobe tumours, not spreading to the midline structures more often demonstrate IDH mutation Z.L. Sun, A. Lai. Moreover, it is wellknown fact, that IDH+ gliomas present with more distinct borders, more homogeneous MR-signal and less frequently demonstrate contrast enhancement A. Lai, G. Reyes-Botero. However, all these characteristics are very subjective and only advisory. More explicit results can be revealed by using MR-perfusion P. Kickingereder, MR-spectroscopy (2-hydroxyglutarat) M.I. de la Fuente and PET B. Suchorska 2017. However, abovementioned methods are not so widespread, unlike MRI, which is capable to predict genetic profile (IDH and 1p/19q status) with almost 100% accuracy. Unconditioned weakness of this method is qualitative, not quantitative his nature, sometimes demanding discussion and still not unambiguous. Probably, future achievements in neuroradiology will allow to perform quantitative analysis of MR-signal and formalize T2/FLAIR mismatch sign.It is difficult to overestimate T2/FLAIR mismatch sign for diagnosis, surgery planning and overall treatment strategy. These aspects were disputed for grade II gliomas Sofietti, A.S. Jakola, M.M.J. Wijnenga. Anaplastic tumours possess worse prognosis and this additional information might be of extreme use. T. Kawaguchi et al. evaluated correlation between radical resection and prognosis of treatment for AA tumours with and without IDHmutation: it turned out, that for IDH-negative tumors radical surgery did not significantly affect overall survival (although these groups demonstrated different OS). On the contrary, radical resection significantly affected OS for IDH+ gliomas. Our study has demonstrated capability T2/FLAIR mismatch sign detection for anaplastic gliomas regardless of tumour contrast enhancement.It is still unclear why not all IDH-positive 1p/19q-negative gliomas demonstrate T2/FLAIR mismatch sign. These “exceptions” were documented earlier by S.H. Patel, M.P.G. Broen for grade II gliomas and in our study for grade III gliomas: only 23 out of 26 patients with above-mentioned molecular profile presented with T2/FLAIR mismatch sign. S.H. Patel et al. speculate about activation of pathways by mTOR protein, which is involved in IDH-positive gliomas malignant change H. Wakimoto, but lack of data precludes authors from statistically significant conclusions.Conclusion. Study results confirm the hypothesis of relevance of T2/T2-FLAIR mismatch sign for anaplastic atrocytomas with contrast enhancement on MRI as highly specific biomarker for tumor genetic profile. In some cases information provided by MRI in this group of patients may improve preoperative diagnostic and affect treatment strategy. Цель исследования: оценка релевантности феномена несоответствия режимов T2 и T2-FLAIR (T2-FLAIR mismatch) в качестве предиктора генетического профиля анапластических астроцитом, в том числе накапливающих контрастный препарат при МРТ-исследовании.Материал и методы. Ретроспективно были проанализированы МР-изображения 242 пациентов, проходивших лечение в ФГАУ “НМИЦ нейрохирургии имени Н.Н. Бурденко” Минздрава России с диагнозом “анапластическая астроцитома” или “анапластическая олигодендроглиома”, тремя нейрорентгенологами на предмет выявления признака T2-FLAIR mismatch и наличия/отсутствия гомогенного повышенного сигнала на Т2-изображениях. Пациенты были включены в основную группу только в случае единого мнения всех трех специалистов относительно названных особенностей изображений опухоли.Результаты. Признак T2-FLAIR mismatch был выявлен у 23 пациентов, у 8 из них опухоль накапливала контрастный препарат при МР-исследовании, в том числе в 3 случаях – выраженно. Возраст пациентов в подгруппе с признаком T2-FLAIR mismatch был достоверно ниже, чем в основной группе (34 года против 42,7 года), как и доля пациентов с контрастируемыми опухолями (36,4% против 55,8%); при этом процент опухолей, выраженно контрастирующихся по МРТ, оказался сопоставим (37,5% против 46,7%).Заключение. Результаты нашего исследования подтверждают релевантность феномена T2-FLAIR mismatch в оценке анапластических астроцитом, в том числе накапливающих контрастный препарат, как высокоспецифичного неинвазивного биомаркера генетического профиля опухоли. Полученные данные в ряде случаев позволят изменить подход к дооперационной диагностике и планированию лечения для определенной части пациентов с анапластическими астроцитомами.