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In this paper we propose a weaker version of Penrose's much heeded Strong Cosmic Censorship (SCC) conjecture, asserting inextendability of maximal Cauchy developments by manifolds with Lipschitz continuous Lorentzian metrics and Riemann curvature bounded in Lp. Lipschitz continuity is the threshold regularity for causal structures, while curvature bounds rule out infinite tidal accelerations, arguing for physical significance of this weaker SCC conjecture. The main result of this paper, under the assumption that no extensions exist with higher connection regularity W loc 1 , p , proves in the affirmative this SCC conjecture with bounded curvature for p sufficiently large, (p > 4 to address uniform bounds, p > 2 without uniform bounds). [ABSTRACT FROM AUTHOR]

We show that taking account of bounded curvature reduces the threshold regularity of connection coefficients required for existence and uniqueness of solutions to the geodesic equation, to L p , one derivative below the regularity W 1 , p required if one does not take account of curvature. We prove curvature in L p gives local existence and curvature in W 1 , p gives uniqueness. Our argument is based on the authors' theory of the RT-equations for regularizing connections to optimal regularity by coordinate transformation. The incoming regularity is too low to formulate a weak version of the geodesic equation based on the standard method of multiplying by smooth test functions and integrating by parts, so alternatively, we define weak solutions by coordinate transformation, and we give an explicit procedure for mollifying the original connection such that the correct weak solution is indeed a limit of smooth solutions of the mollified equations in the original coordinates. This is an example where limits under suitable mollification are more fundamental than a weak formulation, indicative of more complicated PDE's in which the standard weak formulation of the equations does not adequately rule out unphysical solutions. Our results apply to general second order ODE's in which the lack of regularity can be isolated in the connection coefficients. The results apply to General Relativity. [ABSTRACT FROM AUTHOR]

Introduction: Jamaica did not achieve the UNAIDS 90-90-90 targets in 2020. This study aimed to examine trends and factors associated with uptake of HIV treatment among people living with HIV (PLHIV) in Jamaica and to assess the effectiveness of revised treatment guidelines. Methods: This secondary analysis used patient-level data from the National Treatment Service Information System. The baseline sample was 8147 PLHIV initiating anti-retroviral treatment (ART) between January 2015-December 2019. Descriptive statistics were used to summarize demographic and clinical variables and the primary outcome timing of ART initiation. Multivariable logistic regression was used to assess factors associated with ART initiation (same day vs 31+ days), using categorical variables for age group, sex and regional health authority. Adjusted odds ratios and 95% confidence intervals are reported. Results: Most persons initiated ART at 31+ days (n = 3666, 45%) after the first clinic date or on the same day (n = 3461, 43%). Same day ART initiation increased from 37% to 51% over 5 years and was significantly associated with males (aOR = 0.82, CI = 0.74–0.92), 2018 (aOR = 0.66, CI = 0.56–0.77), 2019 (aOR = 0.77, CI = 0.65–0.92). late HIV diagnosis (aOR = 0.3, CI = 0.27–0.33) and viral suppression at the first viral load test (aOR = 0.6, CI = 0.53–0.67). ART initiation at 31+days was associated with 2015 (aOR = 1.21, CI = 1.01–1.45) and 2016 (aOR = 1.30, CI = 1.10–1.53) compared to 2017. Conclusion: Our study shows that same day ART initiation increased between 2015–2019, however it remains too low. Same day initiation was associated with the years after Treat All implementation and late initiation before Treat All, providing evidence of the strategy's success. In order to achieve the UNAIDS targets, there is a need to also increase the number of diagnosed PLHIV retained on treatment in Jamaica. Further studies should be conducted to understand important challenges to accessing treatment as well as differentiated care models to improve treatment uptake and retention. [ABSTRACT FROM AUTHOR]

We announce the extension of optimal regularity and Uhlenbeck compactness to the general setting of connections on vector bundles with non-compact gauge groups over non-Riemannian manifolds, including the Lorentzian metric connections of general relativity (GR). Compactness is the essential tool of mathematical analysis for establishing the validity of approximation schemes. Our proofs are based on the theory of the RT-equations for connections with Lp curvature. Solutions of the RT-equations furnish coordinate and gauge transformations which give a non-optimal connection a gain of one derivative over its Riemann curvature (i.e. to optimal regularity). The RT-equations are elliptic regardless of metric signature, and regularize singularities in solutions of the hyperbolic Einstein equations. As an application, singularities at GR shock waves are removable, implying geodesic curves, locally inertial coordinates and the Newtonian limit all exist. By the extra derivative, we extend Uhlenbeck compactness from Uhlenbeck's setting of vector bundles with compact gauge groups over Riemannian manifolds, to the case of compact and non-compact gauge groups over non-Riemannian manifolds. Our version of Uhlenbeck compactness can also be viewed as a 'geometric' improvement of the Div-Curl Lemma, improving weak continuity of wedge products to strong convergence. [ABSTRACT FROM AUTHOR]

This paper extends a characterization of uniform dissipativity given in a previous publication by two of the authors for second-order hyperbolic systems to an equally natural class of hyperbolic systems of mixed order. These systems are finite-speed-of-propagation counterparts of symmetric hyperbolic-parabolic systems, and the characterizing condition obtained plays a role analogous to the Kawashima condition, inducing decay rates for all Fourier modes in a way that gives – at least for linear constant-coefficients problems, to which this paper restricts attention – uniform decay of solutions in L 2 based Sobolev spaces. [ABSTRACT FROM AUTHOR]

Objective: The study aims to assess changes in HIV treatment outcomes for Jamaica after the implementation of the WHO Treat All strategy in January 2017, as well as identify variables associated with clinical stage at diagnosis and viral load status, in order to understand implications for enhancing the HIV clinical cascade and boosting progress towards the UNAIDS 90-90-90 targets. Method: This is a population-based study using the National Treatment Service Information System. The sample consists of persons 15 years and older, placed on treatment before and after Treat All was implemented, across all 4 regional health authorities in Jamaica. Patients were assessed for two binary outcomes: 1. stage at HIV diagnosis (early/baseline CD4 cell count ≧350 cells/mm3, or late/ baseline CD4 <350 cells/mm3), 2. viral load status achieved after ART initiation (suppressed/<1000 copies/ml or non-suppressed/ ≥1000 copies/ml). Categorical variables: age/years, gender and health regions, were investigated using multivariable logistic regression. Adjusted odds ratios and 95% confidence intervals are reported. Results: After Treat All, there was an increase in median baseline CD4 results as the proportion of late diagnoses decreased from 60% to 39%. There was a small increase in viral suppression from 76% to 80%, a decrease in baseline viral load testing from 61% to 46% and an increase in the uptake of first viral load testing after starting treatment from 13% to 19%. Males and persons 40+ years had higher odds of late diagnosis before and after Treat All. Conclusion: Jamaica's HIV program outcomes have improved after Treat All was implemented. ART initiation time significantly decreased. Early diagnosis, viral load testing uptake and viral suppression increased. However, there is a need to implement targeted testing for men and persons over 40 years to decrease the frequency of late diagnosis. [ABSTRACT FROM AUTHOR]

To further confirm the causality and stability of a second-order hyperbolic system of partial differential equations that models the relativistic dynamics of barotropic fluids with viscosity and heat conduction [H. Freistühler and B. Temple, J. Math. Phys. 59, 063101 (2018)], this paper studies the Fourier–Laplace modes of this system and shows that all such modes, relative to arbitrary Lorentz frames, (a) decay with increasing time and (b) travel at subluminal speeds. Stability is also shown for the related model of non-barotropic fluids [H. Freistühler and B. Temple, Proc. R. Soc. A 470, 20140055 (2014) and H. Freistühler and B. Temple, Proc. R. Soc. A 473, 20160729 (2017)]. Even though these properties had been known for a while in the sense of numerical evidence, the fully analytical proofs for the subluminality of modes of arbitrary wave numbers in arbitrary frames given here appear to be the first regarding any four-field formulation of dissipative relativistic fluid dynamics. [ABSTRACT FROM AUTHOR]

We present the authors' new theory of the RT-equations ('regularity transformation' or 'Reintjes–Temple' equations), nonlinear elliptic partial differential equations which determine the coordinate transformations which smooth connections Γ to optimal regularity, one derivative smoother than the Riemann curvature tensor Riem(Γ). As one application we extend Uhlenbeck compactness from Riemannian to Lorentzian geometry; and as another application we establish that regularity singularities at general relativistic shock waves can always be removed by coordinate transformation. This is based on establishing a general multi-dimensional existence theory for the RT-equations by application of elliptic regularity theory in Lp spaces. The theory and results announced in this paper apply to arbitrary L∞ connections on the tangent bundle TM of arbitrary manifolds M , including Lorentzian manifolds of general relativity. [ABSTRACT FROM AUTHOR]

Summary: Spring phytoplankton blooms in temperate environments contribute disproportionately to global marine productivity. Bloom‐derived organic matter, much of it occurring as polysaccharides, fuels biogeochemical cycles driven by interacting autotrophic and heterotrophic communities. We tracked changes in the mode of polysaccharide utilization by heterotrophic bacteria during the course of a diatom‐dominated bloom in the German Bight, North Sea. Polysaccharides can be taken up in a 'selfish' mode, where initial hydrolysis is coupled to transport into the periplasm, such that little to no low‐molecular weight (LMW) products are externally released to the environment. Alternatively, polysaccharides hydrolyzed by cell‐surface attached or free extracellular enzymes (external hydrolysis) yield LMW products available to the wider bacterioplankton community. In the early bloom phase, selfish activity was accompanied by low extracellular hydrolysis rates of a few polysaccharides. As the bloom progressed, selfish uptake increased markedly, and external hydrolysis rates increased, but only for a limited range of substrates. The late bloom phase was characterized by high external hydrolysis rates of a broad range of polysaccharides and reduced selfish uptake of polysaccharides, except for laminarin. Substrate utilization mode is related both to substrate structural complexity and to the bloom‐stage dependent composition of the heterotrophic bacterial community. [ABSTRACT FROM AUTHOR]

Background: Patients with a lesion within the amygdala and uncus may develop temporal lobe epilepsy despite having functional mesial structures. Resection of functional hippocampus and surrounding structures may lead to unacceptable iatrogenic deficits. To our knowledge, there is limited descriptions of surgical techniques for selectively resecting the amygdala and uncus lesions while preserving the hippocampus in patients with language-dominant temporal lobe pathology. Methods: Thirteen patients with language-dominant temporal lobe epilepsy related to amygdala-centric lesions were identified. Patients with sclerosis of the mesial structures or evidence of pathology outside of the amygdala-uncus region were excluded. Neuropsychological evaluation confirmed normal function of the mesial structures ipsilateral to the lesion. All patients were worked up with video-EEG, high-resolution brain MRI, neuro-psychology evaluation, and either Wada or functional MRI testing. Results: All patients underwent selective resection of the lesion including amygdala and uncus with preservation of the hippocampus via a transcortical inferior temporal gyrus approach to the mesial temporal lobe. Pathology was compatible with glioneuronal tumors. Post-operative MRI demonstrated complete resection in all patients. Eight of the thirteen patients underwent post-operative neuropsychology evaluations and did not demonstrate any significant decline in tasks of delayed verbal recall or visual memory based on the Rey Auditory Verbal Learning Test (RAVLT). One patient showed a slight decrease in confrontation naming using the Boston Naming Test (BNT). Seizure freedom (Engel class I) was achieved in 12 of 13 patients. Conclusion: Selective transcortical amygdala and uncus resection with hippocampus preservation may be a reasonable way to achieve seizure control while sparing functional mesial structures. [ABSTRACT FROM AUTHOR]

This document is a correction notice for a study titled "HIV program outcomes for Jamaica before and after 'Treat All': A population-based study using the national treatment services database." The correction addresses errors in the author contributions section, providing the correct contributions for each author. The authors involved in the study are Anya Cushnie, Ralf Reintjes, Susanna Lehtinen-Jacks, and J. Peter Figueroa. The correction notice ensures accuracy in the attribution of contributions to the study. [Extracted from the article]

We prove that the essential smoothness of the gravitational metric at shock waves in GR, a PDE regularity issue for weak solutions of the Einstein equations, is determined by a geometrical condition which we introduce and name the Riemann-flat condition. The Riemann-flat condition determines whether or not the essential smoothness of the gravitational metric is two full derivatives more regular than the Riemann curvature tensor. This provides a geometric framework for the open problem as to whether regularity singularities (points where the curvature is in L ∞ but the essential smoothness of the gravitational metric is only Lipschitz continuous) can be created by shock wave interaction in GR, or whether metrics Lipschitz at shocks can always be smoothed one level to C 1 , 1 by coordinate transformation. As a corollary of the ideas we give a proof that locally inertial frames always exist in a natural sense for shock wave metrics in spherically symmetric spacetimes, independent of whether the metric itself can be smoothed to C 1 , 1 locally. This latter result yields an explicit procedure (analogous to Riemann normal coordinates in smooth spacetimes) for constructing locally inertial coordinates for Lipschitz metrics, and is a new regularity result for GR solutions constructed by the Glimm scheme. [ABSTRACT FROM AUTHOR]

We show that, when the integration time of the single photon detectors is longer than the correlation time of the biphoton, the attainable spatial resolution in ghost imaging with entangled signal-idler pairs generated in type II spontaneous parametric down conversion is limited by the angular spread of single-frequency-signal-idler pairs. If, however, the detector integration time is shorter than the biphoton correlation time, the transverse k-vectors of different spectral components combine coherently in the image, improving the spatial resolution. [ABSTRACT FROM AUTHOR]

The South Pacific Gyre (SPG) covers 10% of the ocean's surface and is often regarded as a marine biological desert. To gain an on-site overview of the remote, ultraoligotrophic microbial community of the SPG, we developed a novel onboard analysis pipeline, which combines next-generation sequencing with fluorescence in situ hybridization and automated cell enumeration. We tested the pipeline during the SO-245 "UltraPac" cruise from Chile to New Zealand and found that the overall microbial community of the SPG was highly similar to those of other oceanic gyres. The SPG was dominated by 20 major bacterial clades, including SAR11, SAR116, the AEGEAN-169 marine group, SAR86, Prochlorococcus, SAR324, SAR406, and SAR202. Most of the bacterial clades showed a strong vertical (20m to 5,000 m), but only a weak longitudinal (80°W to 160°W), distribution pattern. Surprisingly, n the central gyre, Prochlorococcus, the dominant photosynthetic organism, had only low cellular abundances in the upper waters (20 to 80 m) and was more frequent around the 1% irradiance zone (100 to 150 m). Instead, the surface waters of the central gyre were dominated by the SAR11, SAR86, and SAR116 clades known to harbor light-driven proton pumps. The alphaproteobacterial AEGEAN-169 marine group was particularly abundant in the surface waters of the central gyre, indicating a potentially interesting adaptation to ultraoligotrophic waters and high solar irradiance. In the future, the newly developed community analysis pipeline will allow for on-site insights into a microbial community within 35 h of sampling, which will permit more targeted sampling efforts and hypothesis-driven research. [ABSTRACT FROM AUTHOR]

Microbes in the intestines of mammals degrade dietary glycans for energy and growth. The pathways required for polysaccharide utilization are functionally diverse; moreover, they are unequally dispersed between bacterial genomes. Hence, assigning metabolic phenotypes to genotypes remains a challenge in microbiome research. Here we demonstrate that glycan uptake in gut bacteria can be visualized with fluorescent glycan conjugates (FGCs) using epifluorescence microscopy. Yeast α-mannan and rhamnogalacturonan-II, two structurally distinct glycans from the cell walls of yeast and plants, respectively, were fluorescently labeled and fed to Bacteroides thetaiotaomicron VPI-5482. Wild-type cells rapidly consumed the FGCs and became fluorescent; whereas, strains that had deleted pathways for glycan degradation and transport were non-fluorescent. Uptake of FGCs, therefore, is direct evidence of genetic function and provides a direct method to assess specific glycan metabolism in intestinal bacteria at the single cell level. [ABSTRACT FROM AUTHOR]

Identifying the roles played by individual heterotrophic bacteria in the degradation of high molecular weight (HMW) substrates is critical to understanding the constraints on carbon cycling in the ocean. At five sites in the Atlantic Ocean, we investigated the processing of organic matter by tracking changes in microbial community composition as HMW polysaccharides were enzymatically hydrolysed over time. During this investigation, we discovered that a considerable fraction of heterotrophic bacteria uses a newly-identified 'selfish' mode of substrate processing. We therefore additionally examined the balance of individual substrate utilisation mechanisms at different locations by linking individual microorganisms to distinct substrate utilisation mechanisms. Through FISH and uptake of fluorescently-labelled polysaccharides, 'selfish' organisms were identified as belonging to the Bacteroidetes, Planctomycetes and Gammaproteobacteria. 'Sharing' (extracellular enzyme producing) and 'scavenging' (non-enzyme producing) organisms predominantly belonged to the Alteromonadaceae and SAR11 clades, respectively. The extent to which individual mechanisms prevail depended on the initial population structure of the bacterial community at a given location and time, as well as the growth rate of specific bacteria. Furthermore, the same substrate was processed in different ways by different members of a pelagic microbial community, pointing to significant follow-on effects for carbon cycling. [ABSTRACT FROM AUTHOR]

Qualitative evaluation of the efficiency of composite bridge designs Four different bridge designs have mainly been adopted up to now for composite girder bridges without that there has been performed a systematic analysis of the economy, of the technical quality and of the sustainability of each design approach. This paper will therefore try to develop a generally valid evaluation of the efficiency of the mostly used composite bridge designs. As most important criterion for the efficiency of the different bridge designs the specific rate for the fabrication and erection of the steel structure is defined and its composition analysed in detail. The relation of this specific rate between the two mostly used designs, namely the spacious single cell box‐girder on the one hand and the dual box‐girder design with two smaller box‐girders on the other hand, will be investigated for the example of a common girder bridge. Under the consideration of the available empirical data for the steel weights of executed composite bridges it then will be possible to obtain the relation of the total price for the steel structure of the two different bridge designs. These results will then be extended – not in the same profundity, but still with sufficient accuracy – to the further well known composite bridge designs. This enables the full evaluation of the efficiency of the steel structure for all important composite bridge designs. In order to be able to evaluate the overall efficiency of each composite bridge design it also will be necessary to evaluate the other important cost‐ and performance areas of a composite bridge like the construction of the concrete carriageway, the complex of corrosion protection, inside accesssibility and bridge maintenance as well as the structural redundancy. Only then it will be possible to generate an overall evaluation scheme for all investigated composite bridge designs. [ABSTRACT FROM AUTHOR]

The post-Second World War craft revival in Montana was aided by the formation of the Montana Institute of the Arts (MIA), a grassroots organization that provided connection for various individual practitioners and across disciplines including weaving, ceramics, jewellery making, and woodcarving. The MIA published a quarterly, which provided insights into the development and proliferation of craft in the state in the 1950s through the 1970s, the period of the most robust craft revitalization in the state. Mid-century craft practitioners responded to Montana's rugged geography and vast physical space by developing strategies to further connection and community. [ABSTRACT FROM AUTHOR]

Introduction: Increasing renal care providers offer home hemodialysis (HD) as a modality choice. There is considerable variation in the provision of after‐hours on‐call support for self‐dialyzing patients and no literature describing the utility of this service. In this prospective, observational study we sought to monitor and classify the number and nature of interactions between home patients and our on‐call nurses and technologists, and enumerate the number of adverse events averted by the availability of on‐call staff. Methods: Our home HD unit provided 24‐hour on‐call patient support and during a 4‐month period in 2012, we prospectively monitored all patient calls to this service. The nature of the calls was logged as nursing‐related vs. technical. Call outcomes were classified according to whether patients were able to initiate/resume their treatments or whether additional interventions were required. Findings: During this period, our program cared for 58 home HD patients. Nurses fielded 172 calls and dealt with 239 issues. One hundred nine (46%) were clinical issues including 5 (2%) of a serious nature involving potential harm; 67 (28%) related to machine setup or alarms, 36 (15%) required a technologist to resolve, and 27 (11%) were deemed non‐urgent. One hundred six issues were directed to technologists in 99 calls. Issues pertained to machine malfunction (45 calls—43%), machine set‐up and alarms (25 calls—24%), or the water system (24 calls—23%). Only 12 calls (11.3%) were not of a technical nature. Nursing and technologist support allowed patients to initiate or continue their treatment 75% and 71% of the time, respectively. Discussion: Home HD on‐call services provide patients support to successfully continue their dialysis treatments by troubleshooting clinical and technical aspects of dialysis and by averting potential adverse events. [ABSTRACT FROM AUTHOR]

Abstract The reservoir of dissolved organic carbon (DOC) in the ocean is modified by multiple input and removal processes. Incubation experiments as well as measurements of oceanic DOC have demonstrated that the high molecular weight (HMW) fraction of DOC typically has a younger radiocarbon age and is more reactive biologically than the low molecular weight (LMW) fraction of DOC. These observations have been summarized as a 'size-reactivity continuum' of DOC reactivity, but mechanistic explanations for these observations have been lacking. Here we describe how our recent discovery of 'selfish' HMW organic matter uptake among bacteria in surface ocean waters may help explain the rapid removal of HMW DOC. 'Selfish' substrate uptake by bacteria encompasses rapid binding and partial hydrolysis of intact polysaccharides on the outer membrane of bacteria, seamlessly followed by the transport of large oligosaccharide fragments into the periplasm with little to no loss of LMW hydrolysis products. 'Selfish' bacteria therefore process HMW substrates in a manner distinct from bacteria that carry out extracellular hydrolysis that yields LMW hydrolysis products in the environment. Recognition of the presence and prevalence of selfish bacteria in the ocean has profound implications for carbon flow – the source and quantity of LMW substrates made available to non-extracellular-enzyme producing bacteria – as well as for efforts to model and measure bacterial interactions during organic matter degradation. This discovery also highlights the importance of targeted substrate binding and uptake as key (often understudied) factors in geochemical investigations of microbially driven carbon cycling in the ocean. We conclude with some speculative thoughts about the factors that may determine the prevalence of selfish substrate uptake in the environment. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

We introduce a natural notion of incompressibility for fluids governed by the relativistic Euler equations on a fixed background spacetime, and show that the resulting equations reduce to the incompressible Euler equations in the classical limit as c → ∞. As our main result, we prove that the fluid pressure of solutions of these incompressible „relativistic" Euler equations satisfies an elliptic equation on each of the surfaces orthogonal to the fluid four-velocity, which indicates infinite speed of propagation. [ABSTRACT FROM AUTHOR]

Heterotrophic microbial communities process much of the carbon fixed by phytoplankton in the ocean, thus having a critical role in the global carbon cycle. A major fraction of the phytoplankton-derived substrates are high-molecular-weight (HMW) polysaccharides. For bacterial uptake, these substrates must initially be hydrolysed to smaller sizes by extracellular enzymes. We investigated polysaccharide hydrolysis by microbial communities during a transect of the Atlantic Ocean, and serendipitously discovered-using super-resolution structured illumination microscopy-that up to 26% of total cells showed uptake of fluorescently labelled polysaccharides (FLA-PS). Fluorescence in situ hybridisation identified these organisms as members of the bacterial phyla Bacteroidetes and Planctomycetes and the gammaproteobacterial genus Catenovulum. Simultaneous membrane staining with nile red indicated that the FLA-PS labelling occurred in the cell but not in the cytoplasm. The dynamics of FLA-PS staining was further investigated in pure culture experiments using Gramella forsetii, a marine member of Bacteroidetes. The staining patterns observed in environmental samples and pure culture tests are consistent with a 'selfish' uptake mechanisms of larger oligosaccharides (>600 Da), as demonstrated for gut Bacteroidetes. Ecologically, this alternative polysaccharide uptake mechanism secures substantial quantities of substrate in the periplasmic space, where further processing can occur without diffusive loss. Such a mechanism challenges the paradigm that hydrolysis of HMW substrates inevitably yields low-molecular-weight fragments that are available to the surrounding community and demonstrates the importance of an alternative mechanism of polysaccharide uptake in marine bacteria. [ABSTRACT FROM AUTHOR]

We give a nonperturbative construction of a distinguished state for the quantized Dirac field in Minkowski space in the presence of a time-dependent external field of the form of a plane electromagnetic wave. By explicit computation of the fermionic signature operator, it is shown that the Dirac operator has the strong mass oscillation property. We prove that the resulting fermionic projector state is a Hadamard state. [ABSTRACT FROM AUTHOR]

Background Although intraoperative magnetic resonance imaging (iMRI) increasingly is used during glioma resection, its role in skull base surgery has not been well documented. In this study, we evaluate our experience with iMRI for skull base surgery. Methods Medical records were reviewed retrospectively on all neurosurgical cases performed at our institution in the IMRIS iMRI suite between April 2014 and July 2015. Results During the study period, the iMRI suite was used for 71 skull base tumors. iMRI was performed in 23 of 71 cases. Additional tumor resection was pursued after scanning in 7 of 23 patients. There was a significant difference in procedure length between the scanned versus nonscanned groups, and this was likely attributable to a greater proportion of petroclival meningiomas in the scanned group. Further analyses revealed significant increases in procedure length for the following scanned subgroups: anterolateral approach, anterolateral and petroclival lesion locations, and meningiomas. The rate of non-neurologic complications was significantly greater in the scanned group, particularly for patients with tumors >3 cm. Conclusions Despite the unique challenges associated with skull base tumor surgery, iMRI can be safely obtained while adding a modest although not prohibitive amount of time to the procedure. The immediate evidence of residual tumor with a patient still in position to have additional resection may influence the surgeon to alter the surgical plan and attempt further resection in a critical area. [ABSTRACT FROM AUTHOR]

In the age of ever-increasing "-omics" studies, the accurate and statistically robust determination of microbial cell numbers within often-complex samples remains a key task in microbial ecology. Microscopic quantification is still the only method to enumerate specific subgroups of microbial clades within complex communities by, for example, fluorescence in situ hybridization (FISH). In this study, we improved an existing automatic image acquisition and cell enumeration system and adapted it for usage at high seas on board an oceanographic research ship. The system was evaluated by testing settings such as minimal pixel area and image exposure times ashore under stable laboratory conditions before being brought on board and tested under various wind and wave conditions. The system was robust enough to produce high-quality images even with ship heaves of up to 3m and pitch and roll angles of up to 6.3°. On board the research ship, on average, 25% of the images acquired from plankton samples on filter membranes could be used for cell enumeration. Automated enumeration was highly correlated with manual counts (r2>0.9). Even the smallest of microbial cells in the open ocean, members of the alphaproteobacterial SAR11 clade, could be confidently detected and enumerated. The automated image acquisition and cell enumeration system developed here enables an accurate and reproducible determination of microbial cell counts in planktonic samples and allows insight into the abundance and distribution of specific microorganisms already on board within a few hours. [ABSTRACT FROM AUTHOR]

Nuclear factor kappa B (NF-κB) is an inducible transcription factor that plays critical roles in immune and stress responses and is often implicated in pathologies, including chronic inflammation and cancer. Although much has been learned about NF-κB-activating pathways, the specific repression of NF-κB is far less well understood. Here we identified the type I protein arginine methyltransferase 1 (PRMT1) as a restrictive factor controlling TNFα-induced activation of NF-κB. PRMT1 forms a cellular complex with NF-κB through direct interaction with the Rel homology domain of RelA. We demonstrate that PRMT1 methylates RelA at evolutionary conserved R30, located in the DNA-binding L1 loop, which is a critical residue required for DNA binding. Asymmetric R30 dimethylation inhibits the binding of RelA to DNA and represses NF-κB target genes in response to TNFα. Molecular dynamics simulations of the DNA-bound RelA:p50 predicted structural changes in RelA caused by R30 methylation or a mutation that interferes with the stability of the DNA-NF-κB complex. Our findings provide evidence for the asymmetric arginine dimethylation of RelA and unveil a unique mechanism controlling TNFα/NF-κB signaling. [ABSTRACT FROM AUTHOR]

In 2009, influenza A H1N1 caused the first pandemic of the 21st century. Although a vaccine against this influenza subtype was offered before or at the onset of the second epidemic wave that caused most of the fatal cases in Europe, vaccination rates for that season were lower than expected. We propose that the contradiction between high risk of infection and low use of available prevention measures represents a pandemic public health paradox. This research aims for a better understanding of this paradox by exploring the time-dependent interplay among changing influenza epidemiology, media attention, pandemic control measures, risk perception and public health behavior among five European countries (Czech Republic, Denmark, Germany, Spain and the UK). Findings suggest that asynchronicity between media curves and epidemiological curves may potentially explain the pandemic public health paradox; media attention for influenza A H1N1 in Europe declined long before the epidemic reached its peak, and public risk perceptions and behaviors may have followed media logic, rather than epidemiological logic. [ABSTRACT FROM AUTHOR]

We present a detailed analysis of a previously published realization of Popper’s experiment using entangled ghost imaging. Our analysis, which is based on optical diffraction integrals, shows that, for the configuration previously described, the transverse spread of an unmeasured particle (the signal photon here) does not increase in inverse proportion to the width of its virtual confinement when its entangled twin (the idler photon) is confined in a transverse dimension by a physical slit. Rather, we show that the spread of the unmeasured particle carries no dependence on the width of its virtual confinement in the published configuration. Instead, it spreads geometrically at a rate determined by the numerical aperture of the ghost imaging system. We further propose an alternative configuration for which the spread of the unmeasured particle does increase in inverse proportion to the width of its virtual confinement. We discuss the relation of these results to the predictions of Popper. [ABSTRACT FROM PUBLISHER]

Voltage-gated potassium channel antibody-associated limbic encephalitis (VGKC-LE) is a rare disease that is a diagnostic and therapeutic challenge for medical practitioners. Two patients with VGKC-LE, both developing dementia are presented. Following treatment, both patients showed remarkable cognitive and functional improvement enabling them to leave the psychogeriatric nursing homes they both were admitted to. Patients with VGKC-LE can have a major cognitive and functional improvement even after a diagnostic delay of more than 1 year. Medical practitioners who treat patients with unexplained cognitive decline, epileptic seizures, or psychiatric symptoms should be aware of LE as an underlying rare cause. [ABSTRACT FROM AUTHOR]

We give a constructive proof that coordinate transformations exist which raise the regularity of the gravitational metric tensor from C0,1 to C1,1 in a neighbourhood of points of shock wave collision in general relativity. The proof applies to collisions between shock waves coming from different characteristic families, in spherically symmetric spacetimes. Our result here implies that spacetime is locally inertial and corrects an error in our earlier Proc. R. Soc. A publication, which led us to the false conclusion that such coordinate transformations, which smooth the metric to C1,1, cannot exist. Thus, our result implies that regularity singularities (a type of mild singularity introduced in our Proc. R. Soc. A paper) do not exist at points of interacting shock waves from different families in spherically symmetric spacetimes. Our result generalizes Israel's celebrated 1966 paper to the case of such shock wave interactions but our proof strategy differs fundamentally from that used by Israel and is an extension of the strategy outlined in our original Proc. R. Soc. A publication. Whether regularity singularities exist in more complicated shock wave solutions of the Einstein-Euler equations remains open. [ABSTRACT FROM AUTHOR]

Background The standard incision for far-lateral suboccipital approaches has been the classic "reverse hockey stick." Although that incision provides ample exposure, concern has been raised that excessive muscle dissection and skin elevation might lead to accumulation of cerebrospinal fluid (CSF) under the flap with increased risk of CSF leak. We hypothesize that the C-shaped incision can minimize the amount of muscle dissection and provide optimal exposure and surgical outcomes. Objective To describe the anatomical dissection for the C-shaped incision and clinical application of the C-shaped incision for the far-lateral approach. Methods A retrospective analysis of all the patients operated on at our center using this approach for the treatment of aneurysm of the posterior inferior cerebellar artery (PICA) from 2005 to 2011. Results of clinical and operative outcome are evaluated. Surgical techniques are described in detail. Cadaveric dissections using the C-shaped incision were performed to assess the exposure of the far-lateral suboccipital area. Results Eleven consecutive patients who had undergone this procedure were selected. All patients underwent clipping of PICA aneurysms. Nine patients (82%) presented with ruptured aneurysms and subarachnoid hemorrhage. All of them underwent suboccipital craniectomy and C1 laminectomy. The dura mater was closed in a watertight fashion in 10 patients (91%). No CSF leak or pseudomeningocele were reported. In nine SAH patients, two (22%) had postoperative dysphagia and required long-term percutaneous endoscopic gastrostomy tube placement. One patient (11%) had chronic respiratory failure and required a tracheostomy. Three patients (33%) developed hydrocephalus and required a ventriculoperitoneal shunt. Conclusions The C-shaped incision is a valid alternative to the classic reverse hockey-stick incision to gain exposure for far-lateral craniotomies. Knowing the anatomy and dissection techniques can provide an easy and safe route to address anterior lateral cranial-cervical lesions. Our results suggest the C-shaped incision is reliable in preventing CSF leak and the formation of pseudomeningocele. [ABSTRACT FROM AUTHOR]

Die Brücke über die Süderelbe ist ein wesentlicher Teil der geplanten Verlängerung der Bundesautobahn A 26, die künftig die Bundesautobahnen A 7 und A 1 im Süden des Hamburger Hafens miteinander verbinden soll. Der mögliche Korridor der A 26 für die Querung der Süderelbe ist aufgrund der räumlichen Randbedingungen eng gefasst. Das Kraftwerk Moorburg, der Hafen Hohe Schaar, verschiedene großräumige Betriebsgelände, die vorhandene Trasse der Kattwykstraße und Hafenbahn sowie geplante Bauvorhaben ließen nur eine Querung der Süderelbe in der Nähe der vorhandenen Kattwykbrücke zu. Damit war eine schwierige Aufgabenstellung für die Brücke gegeben. Zur Lösungsfindung wurde ein Realisierungswettbewerb durchgeführt und mit der Preisgerichtssitzung im Mai 2013 abgeschlossen. Der erste Platz wurde einstimmig ausgewählt. Es handelt sich um eine Schrägseilbrücke mit zwei Pylonen, einer Spannweite von 350 m und einer allseits anerkannten, gelungenen Gestaltung mit charakteristischen Entwurfselementen, einem zweigeteilten Überbau und zweigeteilten Pylonen. Auch bei den übrigen Wettbewerbsbeiträgen, es waren insgesamt zwölf Arbeitsgemeinschaften von Ingenieuren und Architekten beteiligt, finden sich Entwürfe, die von besonderem gestalterischen oder technischen Interesse sind. Der Schwerpunkt liegt deutlich bei Schrägkabelbrücken, andere Brückenkonstruktionen wurden allerdings auch vorgeschlagen. Design competition Süderelbe bridge Moorburg - Report on execution and result of the realization competition The bridge across the Süderelbe will be the key structure of the projected extension of the federal motorway A 26, which in future will link the A 7 with the A 1 in the south of the Hamburg harbor. The possible corridor for the alignment of the A 26 across the Süderelbe is confined tightly. The power plant Moorburg, the harbor Hohe Schaar, several industry areas, roads, a railway line lead stringently to a crossing in the neighborhood of the existing Kattwyk Bridge. So, a difficult setting of tasks is given for the design of the bridge. A competition was initiated to find the best design and solution for realization. In May 2013, a jury of clients and experts assessed the works of the twelve participants. The winner is a cable-stayed bridge with two pylons, a main span of 350 m and of a generally approved aesthetic design. Characteristic elements are a dual superstructure and split pylons. Under the other works of the competition are inspirational designs of aesthetical or technical interest, too. [ABSTRACT FROM AUTHOR]

We present an analysis of the transmission of a weak optical pulse, with energy 1ħω0, through a dense absorbing medium with absorption frequency ω0. We analyze the system by treating the optical pulse classically and the absorbing medium quantum mechanically. We find that the probabilistic back reaction of the quantum absorber on the classical pulse impresses statistical behavior on the pulse that does not arise from quantization of the optical field. All properties of the optical transmission and atomic absorption are self-consistent without contradiction. Issues relating to conservation of energy are resolved by considering the impact of superposition states on conservation laws in individual interactions. As a result, we conclude that transmission of a weak optical pulse with energy 1ħω0 through a dense atomic absorber does not require quantization of the field. [ABSTRACT FROM AUTHOR]

It is known that FGFR2 gene variations confer a risk for breast cancer. FGFR2 and FGF10, the main ligand of FGFR2, are both overexpressed in 5–10% of breast tumors. In our study, we sequenced the most important coding regions of FGFR2 in somatic tumor tissue of 140 sporadic breast cancer patients and performed MLPA analysis to detect copy number variations in FGFR2 and FGF10. We identified one somatic heterozygous missense mutation, p.K660N (c.1980G>C), within the tyrosine kinase domain of FGFR2 in tumor tissue of a sporadic breast cancer patient, which is likely mediated by the FGFR2-IIIb isoform. The presence of wild type and mutated alleles in equal quantities suggests that the mutation has driven clonal amplification of mutant cells. We have analyzed the tyrosine kinase activity of p.K660N and another recently described somatic breast cancer mutation in FGFR2, p.R203C, after expression in HEK293 cells and demonstrated that the intrinsic tyrosine kinase activity of both mutant proteins is strongly increased resulting in elevated phosphorylation and activity of downstream effectors. To our knowledge, this is the first report of functional analysis of somatic breast cancer mutations in FGFR2 providing evidence for the activating nature of FGFR2-mediated signalling in the pathogenesis of breast cancer. [ABSTRACT FROM AUTHOR]

Communicable diseases do not respect national boundaries and are important challenges to health internationally. This article aims to support the improvement and integration of surveillance systems in Europe and beyond by drawing on research comparing national systems. Definitions and concepts of epidemiological surveillance are described as a continuous systematic process that observes and reflects the real situation in society not only within but also across political boundaries. Outbreaks that affect more than one country show that a systematic comparative analysis of surveillance systems in Europe can help improve disease control. National surveillance systems from six European Union countries and from a later comparison of twenty-six European countries are examined. An effective surveillance system can provide information for action and act as a monitoring body for health authorities. Nevertheless, many European surveillance systems still require improvement in the interests of public health. [ABSTRACT FROM AUTHOR]

Background: Surveillance of infectious diseases is recognized as the cornerstone of public health decision-making and practice. The aim of the evaluation of communicable diseases surveillance systems (CDSS) is ensuring that communicable diseases are monitored efficiently and effectively. The aim of this paper is to reflect on the experiences of both developed and developing countries in the evaluation of CDSS in order to learn lessons from these experiences to improve systems everywhere. Methods: A literature review of studies published in English in PubMed and databases of the World Health Organization (WHO), and Center of Diseases Control (CDC) from 1981 to 2007 was undertaken assessing CDSS. The studies were divided into those from developed and developing countries. Results: A total of 32 studies were included, 20 from developed and twelve from developing countries. Both developed and developing countries faced difficulties in CDSS. Studies from the developed countries have been analysed based on the quality of the system alone. In developing countries, most of the studies have been on the integrated diseases surveillance (IDSR) and have been performed shortly after the adoption of the IDSR. Thus it might be too early to make a fair evaluation. Some of the systems over-centralized, while some lacked private health sector involvement in the system. Further, some of the systems were affected by conflicts and civil wars which are common problems in developing countries. Conclusions: None of the countries had ideal CDSS. The strategy of integrated diseases surveillance seems to be functioning well especially in Africa. [ABSTRACT FROM AUTHOR]

Abstract: Routine infectious disease surveillance data has to be analysed quickly in order to prevent further disease transmission. This can be done by using epidemiological studies, such as case–control studies. However, these studies are complex to perform and susceptible for biases. An alternative is the case–case study design which is less prone to such limitations. So far mainly methodological publications of this study design exist. In this investigation, outbreak cases are compared with cases infected with the same disease. A Salmonella outbreak was analysed with a case–case study design in order to test the applicability of this method. The analysis showed significant associations to the consumption beef (OR 11.8; 95% CI 2.4–66.7; p<0.001) and pork (OR 8.44; 95% CI 1.7–46.4; p<0.001). A case–control study on the same outbreak confirmed these results. An infected control group is very comparable to the outbreak cluster, which limits selection and recall bias. However, the calculated OR has to be interpreted in context with the study design. The case–case study design has proven to be a useful tool to analyse surveillance data. It was easy to perform and had methodological benefits. [Copyright &y& Elsevier]