Quantum-inspired multicore optical fiber.

We introduce a new, to the best of our knowledge, type of multicore optical fiber having a quantum-inspired network topology and unique spectral features. Particularly, the connectivity between the cores is generated by unfolding a circular array of coupled quantum oscillators in Fock space. We show that in such a fiber geometry, the eigenvalues of the optical supermodes exhibit partial degeneracy and form a ladder. In turn, this leads to revival dynamics, allowing for a periodic re-imaging of the input intensity. As an example, we present a realistic design with six cores in silica glass platforms.

Nonadditive Enhancement of Nonequilibrium Atom-Surface Interactions.

The motion-induced drag force acting on a particle moving parallel to an arrangement of N objects is analyzed. Particular focus is placed on the nonequilibrium statistics of the interaction and on the interplay between the system's geometry and the different dissipative processes occurring in realistic setups. We show that the drag force can exhibit a markedly nonadditive enhancement with respect to the corresponding additive approximation. The specific case of a planar cavity-a relevant configuration for many experiments-is calculated, showing an enhancement of about one order of magnitude. This and similar configurations are of significant potential interest for future measurements that aim to detect the drag force.

Quantum Rolling Friction.

An atom moving in a vacuum at constant velocity and parallel to a surface experiences a frictional force induced by the dissipative interaction with the quantum fluctuations of the electromagnetic field. We show that the combination of nonequilibrium dynamics, the anomalous Doppler effect, and spin-momentum locking of light mediates an intriguing interplay between the atom's translational and rotational motion. In turn, this deeply affects the drag force in a way that is reminiscent of classical rolling friction. Our fully non-Markovian and nonequilibrium description reveals counterintuitive features characterizing the atom's velocity-dependent rotational dynamics. These results prompt interesting directions for tuning the interaction and for investigating nonequilibrium dynamics as well as the properties of confined light.

Detection of Anomalous Cervical Internal Carotid Artery Branches by Colour Duplex Ultrasound.

OBJECTIVES: Conventional anatomical descriptions of the cervical internal carotid artery (ICA) report that no branches arise from this segment. However reports of ICA branches exist. The study aim was to determine the prevalence of anomalous branches of the ICA using colour duplex ultrasound (CDU). METHODS: Four hundred consecutive patients (800 carotid vessels) referred to a tertiary hospital vascular laboratory for investigation of carotid disease were included. A clear differentiation of a low resistive ICA and a high resistive external carotid artery (ECA) waveform was required. CDU was performed on a Philips IU22 ultrasound system with a 9-3 MHz linear array transducer employing a standard carotid imaging protocol. The origin of each ICA branch was identified using B-mode and CDU. Anatomical orientation of ICA branches and distance from bifurcation was recorded and spectral CDU analysis was performed. RESULTS: Twenty ICA branches, tracking cephaladly, were detected in 16 patients (4%), or 2.5% (20/800) vessels. The median age was 73 years; 50% were female and 50% male. All patients demonstrated a single branch [unilateral anomaly (n = 12 patients), bilateral anomaly (n = 4) patients]. Eighty-five percent arose from the posterior wall of the ICA. The median distance from ICA bifurcation was 4 mm (range 0-18 mm). ICA branch diameters ranged from 1.2 mm to 2.4 mm (median 1.4 mm, mean 1.6 mm). Eighty percent of ICA branches had less than 50% stenosis. Spectral analysis revealed high resistive waveforms in all branches. CONCLUSIONS: Branches from the ICA exist and can be characterised with CDU. Prevalence in a tertiary hospital referral cohort is 4%. Given their potential clinical implications, standard carotid imaging protocols should consider routine assessment and reporting of ICA branches.

Prevalence of paediatric inflammatory bowel disease in Sweden: a nationwide population-based register study.

BACKGROUND: We evaluated the impact of different case definition algorithms on the prevalence of paediatric inflammatory bowel disease (IBD), Crohn's disease (CD) and ulcerative colitis (UC) and to compare the occurrence of certain diseases compared to matched controls. METHODS: Paediatric patients (<18 years) were identified via ICD codes for UC and CD in Swedish registers between 1993 and 2010 (n = 1432). Prevalence was defined as ≥2 IBD-related visits. Prevalence of treated children in 2010 was defined as ≥2 IBD-related visits with one visit and ≥1 dispensed IBD-related drug prescription in 2010. To test the robustness of the estimates, prevalence was also calculated according to alternative case definitions. The presence of rheumatic, hepatobiliary, pancreatic, and dermatologic diseases were compared with age-/sex-/county-of-residence-matched general population controls. RESULTS: The IBD prevalence was 75/100,000 (CD: 29/100,000; UC: 30/100,000; patients with IBD-U: 16/100,000). Prevalence of treated disease in 2010 was 62/100,000 (CD: 23/100,000; UC: 25/100,000; patients with IBD-U: 13/100,000). When age restrictions were employed, the prevalence estimate decreased (<17y: 61/100,000, <16y: 49/100,000 and <15y: 38/100,000). Compared to general population controls (n = 8583), children with IBD had a higher prevalence of dermatologic (4.7% vs. 0.6%), hepatobiliary (including primary sclerosing cholangitis) (5.5% vs. 0.1%), pancreatic (1.7% vs. 0%) and rheumatic diseases (7.2% vs. 1.2%; all P < 0.01). CONCLUSIONS: The overall prevalence of paediatric IBD in Sweden was similar to that in earlier regional cohorts. IBD patients had a higher prevalence of comorbid conditions than matched general population controls.

Failure of Local Thermal Equilibrium in Quantum Friction.

Recent progress in manipulating atomic and condensed matter systems has instigated a surge of interest in nonequilibrium physics, including many-body dynamics of trapped ultracold atoms and ions, near-field radiative heat transfer, and quantum friction. Under most circumstances the complexity of such nonequilibrium systems requires a number of approximations to make theoretical descriptions tractable. In particular, it is often assumed that spatially separated components of a system thermalize with their immediate surroundings, although the global state of the system is out of equilibrium. This powerful assumption reduces the complexity of nonequilibrium systems to the local application of well-founded equilibrium concepts. While this technique appears to be consistent for the description of some phenomena, we show that it fails for quantum friction by underestimating by approximately 80% the magnitude of the drag force. Our results show that the correlations among the components of driven, but steady-state, quantum systems invalidate the assumption of local thermal equilibrium, calling for a critical reexamination of this approach for describing the physics of nonequilibrium systems.

Cross-modulation of homeostatic responses to temperature, oxygen and carbon dioxide in C. elegans.

Different interoceptive systems must be integrated to ensure that multiple homeostatic insults evoke appropriate behavioral and physiological responses. Little is known about how this is achieved. Using C. elegans, we dissect cross-modulation between systems that monitor temperature, O2 and CO2. CO2 is less aversive to animals acclimated to 15°C than those grown at 22°C. This difference requires the AFD neurons, which respond to both temperature and CO2 changes. CO2 evokes distinct AFD Ca²âº responses in animals acclimated at 15°C or 22°C. Mutants defective in synaptic transmission can reprogram AFD CO2 responses according to temperature experience, suggesting reprogramming occurs cell autonomously. AFD is exquisitely sensitive to CO2. Surprisingly, gradients of 0.01% CO2/second evoke very different Ca²âº responses from gradients of 0.04% CO2/second. Ambient O2 provides further contextual modulation of CO2 avoidance. At 21% O2 tonic signalling from the O2-sensing neuron URX inhibits CO2 avoidance. This inhibition can be graded according to O2 levels. In a natural wild isolate, a switch from 21% to 19% O2 is sufficient to convert CO2 from a neutral to an aversive cue. This sharp tuning is conferred partly by the neuroglobin GLB-5. The modulatory effects of O2 on CO2 avoidance involve the RIA interneurons, which are post-synaptic to URX and exhibit CO2-evoked Ca²âº responses. Ambient O2 and acclimation temperature act combinatorially to modulate CO2 responsiveness. Our work highlights the integrated architecture of homeostatic responses in C. elegans.

Linear response theory of open systems with exceptional points.

Understanding the linear response of any system is the first step towards analyzing its linear and nonlinear dynamics, stability properties, as well as its behavior in the presence of noise. In non-Hermitian Hamiltonian systems, calculating the linear response is complicated due to the non-orthogonality of their eigenmodes, and the presence of exceptional points (EPs). Here, we derive a closed form series expansion of the resolvent associated with an arbitrary non-Hermitian system in terms of the ordinary and generalized eigenfunctions of the underlying Hamiltonian. This in turn reveals an interesting and previously overlooked feature of non-Hermitian systems, namely that their lineshape scaling is dictated by how the input (excitation) and output (collection) profiles are chosen. In particular, we demonstrate that a configuration with an EP of order M can exhibit a Lorentzian response or a super-Lorentzian response of order Ms with Ms = 2, 3, …, M, depending on the choice of input and output channels.

Giant sponge grounds of Central Arctic seamounts are associated with extinct seep life.

The Central Arctic Ocean is one of the most oligotrophic oceans on Earth because of its sea-ice cover and short productive season. Nonetheless, across the peaks of extinct volcanic seamounts of the Langseth Ridge (87°N, 61°E), we observe a surprisingly dense benthic biomass. Bacteriosponges are the most abundant fauna within this community, with a mass of 460 g C m-2 and an estimated carbon demand of around 110 g C m-2 yr-1, despite export fluxes from regional primary productivity only sufficient to provide <1% of this required carbon. Observed sponge distribution, bulk and compound-specific isotope data of fatty acids suggest that the sponge microbiome taps into refractory dissolved and particulate organic matter, including remnants of an extinct seep community. The metabolic profile of bacteriosponge fatty acids and expressed genes indicate that autotrophic symbionts contribute significantly to carbon assimilation. We suggest that this hotspot ecosystem is unique to the Central Arctic and associated with extinct seep biota, once fueled by degassing of the volcanic mounts.

The oncolytic adenovirus AdΔΔ enhances selective cancer cell killing in combination with DNA-damaging drugs in pancreatic cancer models.

Pancreatic adenocarcinomas are aggressive and frequently develop resistance to all current therapies. Replication-selective adenoviruses can overcome resistance to chemotherapeutics through their sensitizing effects on drug-induced cell killing. We previously found that adenovirus deleted in the anti-apoptotic E1B19K gene enhanced gemcitabine-induced apoptotis. Here we demonstrate that our engineered double-deleted AdΔΔ mutant (deleted in the pRb-binding E1ACR2 region and E1B19K) selectively replicates and enhances cell killing in combination with DNA-damaging cytotoxic drugs in pancreatic cancer cells. Combinations of AdΔΔ with gemcitabine, irinotecan or cisplatin resulted in two- to fourfold decreases in EC(50) (half maximal effective concentration) values and was more efficent than similar combinations with wild-type virus, the dl1520 (ONYX-015) and dl922-947 mutants. AdΔΔ replication was impaired in normal bronchial human epithelial cells and did not sensitize the cells to drugs. Gemcitabine-insensitive AsPC-1, BxPC-3 and PANC-1 cells were efficiently killed by irinotecan in combination with AdΔΔ. Suboptimal doses of AdΔΔ and gemcitabine significantly prolonged time to tumor progression in two human pancreatic tumor xenograft in vivo models, PT45 and SUIT-2. We conclude that AdΔΔ has low toxicity to normal cells while potently sensitizing pancreatic cancer cells to DNA-damaging drugs, and holds promise as an improved therapeutic strategy for pancreatic cancer.

Waveguides in three-dimensional photonic-bandgap materials by direct laser writing and silicon double inversion.

Three-dimensional complete photonic-bandgap materials offer unique opportunities regarding the integration of optical waveguide architectures in three dimensions. However, corresponding experimental realizations are truly sparse. Here, we fabricate such waveguides using direct laser writing and a silicon double-inversion procedure. The optical characterization is in good agreement with theoretical calculations, raising hopes that even more complex architectures may soon come into reach.

Intergenerational learning: A recommendation for engaging youth to address marine debris challenges.

Youth can impact environmental attitudes and behaviors among adults. Indeed, research on intergenerational learning has demonstrated the influence of young people on adults in their lives for myriad environmental topics. Intergenerational learning (IGL) refers to the bidirectional transfer of knowledge, attitudes, or behaviors from children to their parents or other adults and vice versa. We suggest an educational framework wherein K-12 marine debris education designed to maximize IGL may be a strategy to accelerate interdisciplinary, community-level solutions to marine debris. Although technical strategies continue to be developed to address the marine debris crisis, even the most strictly technical of these benefit from social support. Here, we present 10 Best Practices grounded in educational, IGL, and youth civic engagement literature to promote marine debris solutions. We describe how integrating IGL and civic engagement into K-12-based marine debris curricula may start a virtuous circle benefiting teachers, students, families, communities, and the ocean.

Fabrication and characterization of silicon woodpile photonic crystals with a complete bandgap at telecom wavelengths.

By using direct laser writing into a novel commercially available photoresist and a silicon-double-inversion procedure followed by tempering of the silicon structures, we realize high-quality centered-tetragonal woodpile photonic crystals with complete photonic bandgaps near 1.55 microm wavelength. The 6.9% gap-to-midgap ratio bandgap is evidenced by the comparison of measured transmittance and reflectance spectra with band-structure and scattering-matrix calculations.

Mass spectrometry of large, fragile, and involatile molecules.

Desorption ionization makes it possible to obtain mass spectra of molecules whose vaporization by heating may lead to thermal degradation. Several methods are in use, but in general desorption is achieved by particle or photon bombardment of the sample and the mass spectra obtained by different methods are fundamentally similar. Desorption ionization techniques have been used to obtain mass spectra of biomolecules, including peptides, antibiotics, and oligosaccharides, for which normal mass spectral methods have been of limited power. Several examples are given of recent applications of these new techniques, and prospects for their further evolution are discussed.

Mass spectrometry: analytical capabilities and potentials.

The mass range of mass spectrometers has been extended by almost an order of magnitude in the past decade, ionization procedures have been introduced which allow ionic, nonvolatile compounds to be examined, and new capabilities have been achieved through the successful integration of separation and analysis techniques. In combination with other techniques, mass spectrometry has been used in biological and environmental research to characterize constituents of mixtures, including those present in trace amounts; in metabolic profiling, where high throughput and large dynamic range are important; and in protein structure determinations. Measurements of stable isotope abundances by mass spectrometry have been used in enzymology, studies of photosynthesis, and carbon dating. Outside the area of chemical analysis, mass spectrometry has been used to study gas-phase acidities and basicities and to study organic reaction mechanisms in the gas phase. Trends in mass spectrometry include multidimensional experiments, use of ionization methods, direct analysis without extensive sample preparation, and the development of advanced instrumentation including an ion trap and an inductively coupled plasma mass spectrometer. It is likely that mass spectrometry will come to be much more widely used and that data will increasingly be other than conventional mass spectra.

Is superficial burn caused by ultraviolet radiation (sunburn) comparable to superficial burn caused by heat--a histomorphological comparison by in vivo Reflectance-Mode-Confocal Microscopy.

BACKGROUND: Regardless of the underlying cause, both sunburn and superficial thermal injuries are classified as first-degree burns, since data on morphological differences are scarce. Reflectance-Mode-Confocal Microscopy (RMCM) enables high-resolution non-invasive investigation of the human skin. OBJECTIVE: We studied in vivo histomorphological alterations in both sunburn and superficial thermal injuries using RMCM. METHODS: Ten patients (6 female, 4 male; aged 28.4 +/- 10.6 years) with first-degree thermal-contact Injuries (TI group), and 9 sunburned patients (SB group; 7 female, 2 male; aged 30.2 +/- 16.4 years), to a maximum extent of 10% of the body surface were evaluated 24 h after burn injury using RMCM. The following parameters were obtained using RMCM: stratum corneum thickness, epidermal thickness, basal layer thickness, granular cell size. RESULTS: Compared to the controls (12.8 +/- 2.5 microm), stratum corneum thickness decreased significantly to 10.6 +/- 2.1 microm in the TI group, whereas it increased significantly to 16.4 +/- 3.1 microm in the SB group. The epidermal thickness did not differ significantly in the TI group (47.9 +/- 2.3 microm) and SB group (49.1 +/- 3.5 microm); however, both increased significantly compared to their respective controls (41.8 +/- 1.4 microm). The basal layer thickness increased more in the SB group compared to the TI group (17.9 +/- 1.4 microm vs. 15.6 +/- 1.1 microm). Both differed also significantly compared to their controls (13.8 +/- 0.9 microm). The granular cell size increased significantly in both groups compared to the controls (731 +/- 42 microm); however, a significantly higher increase was observed in the TI group (852 +/- 58 microm) compared to the SB group (784 +/- 61 microm). CONCLUSIONS: Ultraviolet radiation seems to influence predominantly deeper epidermal layers, whereas heat-induced burns affect more superficial epidermal layers. The term 'First-degree burn' should not be used synonymously for sunburn and superficial thermal burn injuries. Conflicts of interest None declared.

Identification of two distinct MYC breakpoint clusters and their association with various IGH breakpoint regions in the t(8;14) translocations in sporadic Burkitt-lymphoma.

The chromosomal translocation t(8;14) is the hallmark of Burkitt's-lymphoma (BL) and fuses the proto-oncogene c-MYC to the IGH locus. We analyzed the genomic structure of MYC/IGH fusions derived from a large series of 78 patients with t(8;14) and asked (i) whether distinct breakpoint clusters exist within the MYC gene and (ii) whether any pairwise association between particular IGH and MYC breakpoints exist. Identification of such associations will help elucidate the etiology of the breaks on the MYC locus. Scan statistic analyses revealed two distinct, but large clusters within c-MYC containing 60/78 (77%) of the breakpoints. Clusters 1 and 2 were 560 and 779 bp in length within a 4555 bp breakpoint cluster region. Breaks within IGH switch mu and joining region did not differ with respect to their corresponding MYC breakpoints. However, there was a highly significant correlation between breakpoints 5' of MYC cluster 1 and fusions to IGH switch gamma region and breakpoints downstream of MYC cluster 2 and fusions to IGH switch alpha region (chi(2)-test: P<0.005). Chromatin changes governing choice of IGH-Fc region recombination may parallel changes in the MYC gene 5' region chromatin leading to some degree of coordinated ontological specificity in breakpoint location.

[A flap simulator for training in local defect coverage]. / Lappensimulator für lokale Defektdeckungen: Flap Lab I der MHH.

The Hannover Medical School (Germany) developed the"Flap Lab I" flap simulator, a practical improvement to surgeon training. It provides realistic conditions for understanding and following the principles for planning and performing local flaps for coverage of skin defects. The Flap Lab I has proved to be a very good training model in several training courses. This article introduces among others the Z-flap, reverse Z-flap (so-called hanging man), and Limberg flap.

High frequency of unrecognized hypoglycaemias in patients with Type 2 diabetes is discovered by continuous glucose monitoring.

AIMS: To evaluate the use of a CGMS in the detection of hypoglycaemia in people with type 2 diabetes as an outpatient procedure. METHODS: 31 type 2 diabetic patients underwent glucose monitoring by means of CGMS (Medtronic MiniMed) for up to three days. Patients took part in at least four SMBG (self monitoring blood glucose) tests per day. After three days of monitoring, the CGMS data was downloaded and analysed by a physician to identify the frequency of hypoglycaemias (< or =50 mg/dl) and borderline values (51-70 mg/dl), their duration and distribution. Findings were discussed with the patient and if necessary treatment was adjusted. Eight weeks later, monitoring was repeated to asses the effects of the adjusted treatment. RESULTS: Average duration of sensor wear was 4.19 days. Correlation between the sensor and the SMBG readings was high. A high number of hypoglycaemias and borderline values were detected by the CGMS, most of them unrecognized by the patient. The frequency of hypoglycaemias and borderline values just as the duration could be significantly reduced from first to second monitoring. CONCLUSION: Using the CGMS in type 2 diabetic patients achieved the detection of numerous hypoglycaemias and borderline values both nocturnal and/or unnoticed. The CGMS provides accurate data, which cannot be achieved by conventional SMBG tests. That opens the possibility for treatment adjustment and improvement in metabolic control. For patients it provides a better understanding of the effects of insulin or oral agents, nutrition and exercises to their glucose level.