Optical Spin-Wave Storage in a Solid-State Hybridized Electron-Nuclear Spin Ensemble.

Solid-state impurity spins with optical control are currently investigated for quantum networks and repeaters. Among these, rare-earth-ion doped crystals are promising as quantum memories for light, with potentially long storage time, high multimode capacity, and high bandwidth. However, with spins there is often a tradeoff between bandwidth, which favors electronic spin, and memory time, which favors nuclear spins. Here, we present optical storage experiments using highly hybridized electron-nuclear hyperfine states in ^{171}Yb^{3+}:Y_{2}SiO_{5}, where the hybridization can potentially offer both long storage time and high bandwidth. We reach a storage time of 1.2 ms and an optical storage bandwidth of 10 MHz that is currently only limited by the Rabi frequency of the optical control pulses. The memory efficiency in this proof-of-principle demonstration was about 3%. The experiment constitutes the first optical storage using spin states in any rare-earth ion with electronic spin. These results pave the way for rare-earth based quantum memories with high bandwidth, long storage time, and high multimode capacity, a key resource for quantum repeaters.

Optimal Coherent Filtering for Single Noisy Photons.

We introduce a filter using a noise-free quantum buffer with large optical bandwidth that can both filter temporal-spectral modes as well as interconvert them and change their frequency. We theoretically show that such quantum buffers optimally filter out temporal-spectral noise, producing identical single photons from many distinguishable noisy single-photon sources with the minimum required reduction in brightness. We then experimentally demonstrate a noise-free quantum buffer in a warm atomic system that is well matched to quantum dots. Based on these experiments, simulations show that our buffer can outperform all intensity (incoherent) filtering schemes for increasing indistinguishability.

Cavity-Enhanced Room-Temperature Broadband Raman Memory.

Broadband quantum memories hold great promise as multiplexing elements in future photonic quantum information protocols. Alkali-vapor Raman memories combine high-bandwidth storage, on-demand readout, and operation at room temperature without collisional fluorescence noise. However, previous implementations have required large control pulse energies and have suffered from four-wave-mixing noise. Here, we present a Raman memory where the storage interaction is enhanced by a low-finesse birefringent cavity tuned into simultaneous resonance with the signal and control fields, dramatically reducing the energy required to drive the memory. By engineering antiresonance for the anti-Stokes field, we also suppress the four-wave-mixing noise and report the lowest unconditional noise floor yet achieved in a Raman-type warm vapor memory, (15±2)×10^{-3} photons per pulse, with a total efficiency of (9.5±0.5)%.

Clinical implementation of cardiac resynchronization therapy-regional disparities across selected ESC member countries.

BACKGROUND: The present analysis aimed to estimate the penetration of cardiac resynchronization therapy (CRT) on the basis of the prevalence and incidence of eligible patients in selected European countries and in Israel. METHODS AND RESULTS: The following countries were considered: Italy, Slovakia, Greece, Israel, Slovenia, Serbia, the Czech Republic, Poland, Romania, Hungary, Ukraine, and the Russian Federation. CRT penetration was defined as the number of patients treated with CRT (CRT patients) divided by the prevalence of patients eligible for CRT. The number of CRT patients was estimated as the sum of CRT implantations in the last 5 years, the European Heart Rhythm Association (EHRA) White Book being used as the source. The prevalence of CRT indications was derived from the literature by applying three epidemiologic models, a synthesis of which indicates that 10% of heart failure (HF) patients are candidates for CRT. HF prevalence was considered to range from 1% to 2% of the general population, resulting in an estimated range of prevalence of CRT indication between 1000 and 2000 patients per million inhabitants. Similarly, the annual incidence of CRT indication, representing the potential target population once CRT has fully penetrated, was estimated as between 100 and 200 individuals per million. The results showed the best CRT penetration in Italy (47-93%), while in some countries it was less than 5% (Romania, Russian Federation, and Ukraine). CONCLUSION: CRT penetration differs markedly among the countries analyzed. The main barriers are the lack of reimbursement for the procedure and insufficient awareness of guidelines by the referring physicians.

Evaluation of image-guidance strategies for prostate cancer.

In this study, set-up accuracy and time consumption of different image-guidance protocols used for prostate cancer patients were compared. Set-up corrections from 60 prostate cancer patients treated on helical tomotherapy (HT) were used to simulate four types of image-guidance protocols which were based on: (i) a limited number of imaging sessions (IG-1), (ii) reduced registration tasks during daily imaging (IG-2), or (iii) and (iv) mixed methods of imaging (IG-3, IG-4). Each protocol was evaluated for three referencing scenarios based on the first fraction, first three fractions and first five fractions. Residual set-up error, the difference between the average set-up correction and the actual correction required, was used to evaluate the accuracy of each protocol. The first five fractions referencing scenario provides the highest reduction of the margins for each image-guidance protocol evaluated in this study. The first type of protocol is the shortest way to the effective correction of the systematic component of set-up error. For the second type of the protocol, the control of the residual errors is better and, as a result, the reduction of the margins is more significant than that obtained for the first one. Moreover, the second type of the protocol provides the highest accuracy of delivered dose. The result obtained for the fourth type of protocol does not decrease the calculated margins or increase their accuracy in correspondence to the no image guidance scheme. The fourth type of the protocol is not recommended as a protocol to be used to increase the conformity of the dose. The choice of the rest protocols should be validated in the context of (i) institutional practice regarding patient set-up procedure and its time consumption, (ii) acceptable balance between the amount of the dose delivered to the organ at risk and the additional imaging dose and (iii) patient anatomical conditions.

Avian influenza viruses in wild birds at the Jeziorsko reservoir in Poland in 2008-2010.

During a 3-year surveillance study for avian influenza virus (AIV) infections at the Jeziorsko reservoir in central Poland, 549 oropharyngeal or cloacal swabs from 366 birds of 14 species belonging to 3 orders (Anseriformes, Charadriiformes and Gruiformes) were tested. AIV was detected in 14 birds (3.8%): Common Teals (12x), Mallard (1x) and Garganey (1x). Three potentially dangerous H5 AIV were detected in Common Teals (2x) and Garganey (1x) but all of them revealed a low pathogenic pathotype. A unique cleavage site amino acid motif PQREIR*GLF was found in one H5 isolate from a Garganey.

The tongue display unit (TDU) for electrotactile spatiotemporal pattern presentation.

The Tongue Display Unit (TDU) is a 144-channel programmable pulse generator that delivers dc-balanced voltage pulses suitable for electrotactile (electrocutaneous) stimulation of the anterior-dorsal tongue, through a matrix of surface electrodes. This article reviews the theory of operation and a design overview of the TDU, as well as selected applications. These include sensory substitution, tactile information display and neurorehabilitation via induced neuroplasticity.

Ccdc33, a predominantly testis-expressed gene, encodes a putative peroxisomal protein.

Many genes crucial for male fertility are often predominantly or exclusively expressed in male germ cells. The analysis of mouse models has demonstrated the functional importance of peroxisomes in spermatogenesis. The CCDC33 protein has been reported to be a cancer/testis (CT) antigen. We found that mouse Ccdc33 is predominantly expressed in the testis and undergoes alternative splicing to produce at least 4 different transcripts. The protein encoded by Ccdc33 contains 3 coiled-coil domains, a C2-domain, 2 ER membrane retention signal-like motifs and 2 putative peroxisomal targeting signals type 2 (PTS2). We could demonstrate that the second PTS2 sequence is functional and responsible for the targeting of CCDC33 to peroxisomes. Moreover, in HeLa cells CCDC33-dsRED fusion protein co-localized with a known peroxisomal protein, namely PXT1, and showed punctuate intracellular distribution. Taken together, the mouse Ccdc33 encodes a putative peroxisomal protein and is predominantly expressed in male germ cells. The expression starts at the primary spermatocyte stage, suggesting an important role of this protein during spermatogenesis.

Comparison of insect kinin analogs with cis-peptide bond, type VI-turn motifs identifies optimal stereochemistry for interaction with a recombinant arthropod kinin receptor from the southern cattle tick Boophilus microplus.

The multifunctional 'insect kinins' share the evolutionarily conserved C-terminal pentapeptide motif Phe-X1-X2-Trp-Gly-NH2, where X1=His, Asn, Ser, or Tyr and X2=Ser, Pro, or Ala; and are associated with the regulation of diuresis in a variety of species of insects. We previously reported the functional expression of a southern cattle tick (Boophilus microplus) G protein-coupled receptor that is activated by insect kinins. Four different stereochemical variants of each of the 4-aminopyroglutamic acid (APy) and tetrazole moieties, mimics of a cis-peptide bond, type VI beta-turn in insect kinins were now evaluated on the expressed tick receptor using a calcium bioluminescence plate assay. This study represents the first investigation of the interaction of restricted-conformation analogs incorporating components that mimic specific conformations and/or peptide bond orientations in an expressed arthropod neuropeptide receptor. Analog Ac-RF[APy]WGa (2R,4S) was at least 10-fold more active than the other analogs, thus identifying the optimal stereochemistry for tick receptor interaction. The optimal stereochemistry for the tetrazole insect kinin analogs in the tick receptor assay was identified as (D,L). The APy is superior to the tetrazole as a scaffold for the design of mimetic insect kinin analogs. These biostable analogs provide new tools for arthropod endocrinologists and potential leads in the development of selective, environmentally friendly arthropod pest control agents capable of disrupting insect kinin regulated processes.

[Intermittent ciliary block as a result of haemodialysis]. / Intermittierender ziliarer Block durch Hämodialyse.

We report the case of a patient who experienced recurrent elevations of intraocular pressure during haemodialysis. We measured a rise in intraocular pressure of 10-12 mmHg after dialysis. The lens showed intumescence, and a ciliary block was detected by means of Orbscan II. Within 6 h findings had normalized. Changes in serum osmolarity due to haemodialysis may result in fluid shifts between different compartments. Decrease of serum osmolarity during dialysis may lead to lens swelling and thus cause a ciliary block. This may end with regression of the lens swelling.

[Differentiation between pupillary and ciliary block by means of the Orbscan II in a patient with angle block glaucoma]. / Differenzierung zwischen Pupillar- und Ziliarblock mithilfe des Orbscan II bei einem Patienten mit Winkelblockglaukom.

BACKGROUND: A ciliary block is the rarer cause of angle block glaucoma. In order to choose the appropriate therapy, however, it is crucial to make the correct diagnosis. We report on a patient who suffered from recurrent increases of intraocular pressure while having renal dialysis. In his case the use of the Orbscan II made the differentiation between a pupillary and a ciliary block easier. CASE REPORT: In addition to basic ophthalmological examinations we performed a topographic analysis using Orbscan II before and after renal dialysis. Since intraocular pressure rise during renal dialysis had been proven, iridotomies on both eyes and an iridectomy on the left one had been performed before the patient was referred to us. In spite of these open shunts we measured an increase of intraocular pressure values of 10 to 12 mmHg directly after renal dialysis had been completed. The anterior chamber became shallower both at its centre and the periphery, thus its volume diminished analogously. Measurements by the Orbscan II showed that the lens swelled up and was displaced anteriorly as well, so that a ciliary block mechanism had to be assumed. CONCLUSIONS: Since the Orbscan II is capable of collecting topometric data of the cornea, anterior chamber and also lens, it is helpful in differentiating a pupillary from a ciliary block in angle block glaucoma.

Electrotactile perception of scatterplots on the fingertips and abdomen.

A comparison of auditory and visual perception of scatterplots showed similar correlation estimation performance in both modalities. The present study replicated this experiment using electrotactile (electrocutaneous) presentation of scatterplots on the fingertips and abdomen, as well as visual presentation. The correlation estimation task resulted in a slightly poorer performance on electrotactile scatterplots (abdomen r = +0.847; fingertip r = +0.723) compared with the previous Flowers auditory displays (r = +0.91). There were similar levels of performance in the visual (control) condition in both the studies (r for both approx. +0.91). The performance in the correlation estimation task was similar across the two electrotactile displays, with perhaps a slight, but not significant (p = 0.077), advantage for the abdominal array. However, a preliminary digit identification task on both displays produced a better performance on the fingertip display (p < 0.05), suggesting that the relative performance of the two displays may be task specific. The present results demonstrate electrotactile perception of complex graphs and provide useful information for improving future versions of tactile displays.

Matching 2D gel electrophoresis images.

Automatic alignment (matching) of two-dimensional gel electrophoresis images is of primary interest in the field of proteomics. The proposed method of 2D gel image matching is based on fuzzy alignment of features, extracted from gels' images, and it allows both global and local interpolation of image grid, followed by brightness interpolation. Method performance is tested on simulated images and gel images available via the Internet databases.

Feature based fuzzy matching of 2D gel electrophoresis images.

Automatic alignment (matching) of two-dimensional gel electrophoresis images is of primary interest in the evolving field of proteomics. In the present study, feature-based matching techniques, in their classical and robust versions, are described, and an automatic method of fuzzy alignment (FA) is introduced. This method allows automatic matching of two gel images with different numbers of features with unknown correspondence. Performance of FA is tested on simulated and real data sets.

C(alpha)-hydroxymethyl methionine: synthesis, optical resolution and crystal structure of its (+)-N(alpha)-benzoyl derivative.

(R, S)-Methionine was transformed into C(alpha)-hydroxymethyl methionine by a route involving C(alpha)-hydroxymethylation of 2-phenyl-4-methylthioethyl-5-oxo-4,5-dihydro-1,3-oxazole. The absolute configuration of (-)-C(alpha)-hydroxymethyl methionine was elucidated to be (S) by chemical correlation with (S) (-)-C(alpha)-ethyl serine. Absolute structure determination (by single crystal X-ray diffraction) on N(alpha)-benzoyl-C(alpha)-hydroxymethyl methionine confirmed the (R)-configuration for the (+)-enantiomer. In addition, the X-ray diffraction analysis showed that the C(alpha,alpha)-disubstituted glycyl residue adopts the fully extended (C5) conformation.

A novel cis-peptide bond motif inducing beta-turn type VI. The synthesis of enkephalin analogues modified with 4-aminopyroglutamic acid.

A new pathway leading to a mixture of four isomers of 4-aminopyroglutamic acid is described. Michael type addition of Z-deltaAla-OMe to enolates prepared from acylaminomalonates, followed by hydrolysis and decarboxylation give protected 4-aminopyroglutamic acid with the cis:trans ratio approximately 3:2. This mixture was incorporated into Leu-enkephalin (position 2-3). After separation of peptides it appeared that all analogues were essentially inactive in guinea pig ileum and mouse vas deferens bioassays.

[Mitral valve prolapse--diagnostic and therapeutic implications]. / Wypadanie platka zastawki mitralnej--implikacje diagnostyczne i terapeutyczne.

In the most patients the mitral valve prolapse (MVP) syndrome has a good prognosis. The gradual progression of MR may cause the progressive LV dysfunction and development of heart failure. Long-term prognostic studies showed, that complications like endocarditis, cerebrovascular accidents occur frequently in pts. with mitral systolic murmur, thickened mitral valve leaflets and presence of MR. The diagnosis of MVP is made by cardiac auscultation and confirmed by echocardiography. The procedures usefulness in sudden death stratification are discussed. The management of the symptomatic patients, particularly the indication for prophylaxis of endocarditis and cerebrovascular accidents has been demonstrated. The indications for cardiac catheterisation and surgical treatment are presented.

The afferent neural response to electrotactile stimuli: preliminary results.

We recorded action potentials from three RA fibers innervating primate fingerpad, while applying electrotactile (electrocutaneous) stimulation. Negative pulses required 1.3-1.5 times more current than positive ones for entrainment. The strength-duration time constant was approximately 151 micros. Suprathreshold sinusoidal vibration synchronized to 30-Hz electrotactile pulses changed the electrotactile entrainment current slightly, indicating a possible electrical-mechanical transduction interaction.

Electrotactile adaptation on the abdomen: preliminary results.

Electrotactile (electrocutaneous) stimulation at currents greater than sensation threshold causes sensory adaptation, which temporarily raises the sensation threshold and reduces the perceived magnitude of stimulation. After 15 min of moderately intense exposure to a conditioning stimulus (10 s on, 10 s off), the sensation threshold elevation for seven observers was 60-270%, depending on the current, frequency, and number of pulses in the burst structure of the conditioning stimulus. Increases in any of these parameters increased the sensation threshold elevation. Adaptation and recovery were each complete in approximately 15 min.

Morphometric study of the muscles spindles of the eye muscle in human fetuses between 24-29 weeks.

The studies were carried out on human fetuses with the crow-rump length between 230 to 270 mm (24-29 weeks). The length of recti muscles varies from 12-15 mm in 24th week to 25-28 mm in 29th week. Number of muscle spindles varies from 29-36 in 24th week to 54-59 in 29th week. The length of the muscle spindles is from 30-300 microns in 24th week to 40-450 microns in 29th week. The diameter of the muscle spindles varies from 11-36 microns in 24th week to 15-70 microns in 29th week.