ATR based infrared spectroscopy for the diagnosis of neonatal respiratory distress syndrome

Optical spectroscopy offers a potential non-invasive, label free and rapid method to assist clinicians to diagnose diseases for which biomarkers are known. Neonatal respiratory distress syndrome (nRDS) diagnosis in preterm infants is known to be correlated with the lecithin/sphingomyelin ratio (LS ratio) in gastric aspirates, with a ratio less than 2.2 indicating that surfactant replacement therapy is needed. Currently no widespread method exists that can give clinically relevant answers in less than 2 hours from the point of sample collection as it is difficult to identify those who could benefit from prompt surfactant treatment. Various LS ratios were generated using pure dipalmitoylphosphatidylcholine (DPPC) and sphingomyelin (SM) dissolved in dichloromethane and infrared spectra generated using Attenuated Total Reflection (ATR) assisted Fourier Transform InfraRed spectrometry (FTIR). Subsequent analysis obtained the LS ratio using the spectra alone. Further, we demonstrate the application of principal component regression (PCR) and partial least squares (PLS) fits to measured spectra to assist in the determination of the LS ratio using a model trained with multiple runs of the different batches of the same concentration

Prediction of Neonatal Respiratory Distress Biomarker Concentration by Application of Machine Learning to Mid-Infrared Spectra

The authors of this study developed the use of attenuated total reflectance Fourier transform infrared spectroscopy (ATR–FTIR) combined with machine learning as a point-of-care (POC) diagnostic platform, considering neonatal respiratory distress syndrome (nRDS), for which no POC currently exists, as an example. nRDS can be diagnosed by a ratio of less than 2.2 of two nRDS biomarkers, lecithin and sphingomyelin (L/S ratio), and in this study, ATR–FTIR spectra were recorded from L/S ratios of between 1.0 and 3.4, which were generated using purified reagents. The calibration of principal component (PCR) and partial least squares (PLSR) regression models was performed using 155 raw baselined and second derivative spectra prior to predicting the concentration of a further 104 spectra. A three-factor PLSR model of second derivative spectra best predicted L/S ratios across the full range (R2: 0.967; MSE: 0.014). The L/S ratios from 1.0 to 3.4 were predicted with a prediction interval of +0.29, −0.37 when using a second derivative spectra PLSR model and had a mean prediction interval of +0.26, −0.34 around the L/S 2.2 region. These results support the validity of combining ATR–FTIR with machine learning to develop a point-of-care device for detecting and quantifying any biomarker with an interpretable mid-infrared spectrum

The labor market regimes of Denmark and Norway – one Nordic model?

The literature on the Danish and Norwegian labor market systems emphasizes the commonalities of the two systems. We challenge this perception by investigating how employers in multinational companies in Denmark and Norway communicate with employees on staffing changes. We argue that the development of ‘flexicurity’ in Denmark grants Danish employers considerably greater latitude in engaging in staffing changes than its Nordic counterpart, Norway. Institutional theory leads us to suppose that large firms located in the Danish setting will be less likely to engage in employer–employee communication on staffing plans than their Norwegian counterparts. In addition, we argue that in the Danish context indigenous firms will have a better insight into the normative and cognitive aspects to flexicurity than foreign-owned firms, meaning that they are more likely to engage in institutional entrepreneurialism than their foreign owned counterparts. We supplement institutional theory with an actor perspective in order to take into account the role of labor unions. Our analysis is based on a survey of 203 firms in Norway and Denmark which are either indigenous multinational companies or the subsidiaries of foreign multinational companies. The differences we observe cause us to conclude that the notion of a common Nordic model is problematic

An intriguing relationship between the cyclic diguanylate signaling system and horizontal gene transfer

The second messenger cyclic diguanylate (c-di-GMP) is ubiquitously used by bacteria to modulate and shift between different phenotypes including motility, biofilm formation and virulence. Here we show that c-di-GMP-associated genes are widespread on plasmids and that enzymes that synthesize or degrade c-di-GMP are preferentially encoded on transmissible plasmids. Additionally, expression of enzymes that synthesize c-di-GMP was found to increase both biofilm formation and, interestingly, conjugative plasmid transfer rates

A monolithic integrated photonic microwave filter

[EN] Meeting the increasing demand for capacity in wireless networks requires the harnessing of higher regions in the radiofrequency spectrum, reducing cell size, as well as more compact, agile and power-efficient base stations that are capable of smoothly interfacing the radio and fibre segments. Fully functional microwave photonic chips are promising candidates in attempts to meet these goals. In recent years, many integrated microwave photonic chips have been reported in different technologies. To the best of our knowledge, none has monolithically integrated all the main active and passive optoelectronic components. Here, we report the first demonstration of a tunable microwave photonics filter that is monolithically integrated into an indium phosphide chip. The reconfigurable radiofrequency photonic filter includes all the necessary elements (for example, lasers, modulators and photodetectors), and its response can be tuned by means of control electric currents. This is an important step in demonstrating the feasibility of integrated and programmable microwave photonic processors.The authors acknowledge financial support from the Spanish Centro para el Desarrollo Tecnologico Industrial (CDTI) through the NEOTEC start-up programme, the European Commission through the 7th Research Framework Programme project, Photonic Advanced Research and Development for Integrated Generic Manufacturing (FP7-PARADIGM), the Generalitat Valenciana through the Programa para grupos de Investigacion de Excelencia (PROMETEO) project code 2013/012, the Spanish Ministerio de Economia y Comercio (MINECO) via project TEC2013-42332-P, PIF4ESP, and the Unwersitat Politecnica de Valencia (UPVOV) through projects 10-3E-492 and 08-3E-008 funded by the Fondos Europeos de Desarrollo Regional (FEDER). J.S. Fandino acknowledges financial support from Formacion de Profesorado Universitario (FPU) grant AP2010-1595.Sanchez Fandiño, JA.; Muñoz Muñoz, P.; Doménech Gómez, JD.; Capmany Francoy, J. (2017). A monolithic integrated photonic microwave filter. Nature Photonics. 11(2):124-129. https://doi.org/10.1038/NPHOTON.2016.233S124129112Novak, D. et al. Radio-over-fiber technologies for emerging wireless systems. IEEE J. Quantum Electron. 52, 1–11 (2016).Waterhouse, R. & Novak, D. Realizing 5G: microwave photonics for 5G mobile wireless systems. IEEE Microw. Mag. 16, 84–92 (2015).Won, R. Microwave photonics shines. Nat. Photon. 5, 736 (2011).Capmany, J. & Novak, D. Microwave photonics combines two worlds. Nat. Photon. 1, 319–330 (2007).Yao, J. Microwave photonics. J. Lightw. Technol. 27, 314–335 (2009).Andrews, J. G. et al. What will 5G be? IEEE J. Sel. Areas Commun. 32, 1065–1082 (2014).Gosh, A., et al. 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Integrated InP–InGaAsP tuneable coupled ring optical bandpass filters with zero insertion loss. Opt. Express 19, 7816–7826 (2011).Fandiño, J. S. & Muñoz, P. Photonics-based microwave frequency measurement using a double-sideband suppressed-carrier modulation and an InP integrated ring-assisted Mach–Zehnder interferometer filter. Opt. Lett. 38, 4316–4319 (2013).Burla, M. et al. On-chip ultra-wideband microwave photonic phase shifter and true time delay line based on a single phase-shifted waveguide Bragg grating. In IEEE International Topical Meeting on Microwave Photonics 92–95 (IEEE, 2013).Shi, W., Veerasubramanian, V., Patel, D. & Plant, D. Tuneable nanophotonic delay lines using linearly chirped contradirectioinal couplers with uniform Bragg gratings. Opt. Lett. 39, 701–703 (2014).Guan, B. et al. CMOS compatible reconfigurable silicon photonic lattice filters using cascaded unit cells for RF-photonic processing. IEEE J. Sel. Top. Quantum Electron. 20, 359–368 (2014).Khan, M. 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Impulse radio ultrawideband pulse shaper based on a programmable photonic chip frequency discriminator. Opt. Express 19, 24838–24848 (2011).Marpaung, D. On-chip photonic-assisted instantaneous microwave frequency measurement system. IEEE Photon. Technol. Lett. 25, 837–840 (2013).Burla, M. et al. On-chip CMOS compatible reconfigurable optical delay line with separate carrier tuning for microwave photonic signal processing. Opt. Express 19, 21475–21484 (2011).Tan, K. et al. Photonic-chip-based all-optical ultra-wideband pulse generation via XPM and birefringence in a chalcogenide waveguide. Opt. Express 21, 2003–2011 (2013).Pagani, M. et al. Tuneable wideband microwave photonic phase shifter using on-chip stimulated Brillouin scattering. Opt. Express 22, 28810–28818 (2014).Pérez, D., Gasulla, I. & Capmany, J. Software-defined reconfigurable microwave photonics processor. Opt. Express 23, 14640–14654 (2015).Capmany, J., Gasulla, I. & Pérez, D. 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Undular tidal bores: Effect of channel constriction and bridge piers

A tidal bore may occur in a macro-tidal estuary when the tidal range exceeds 4.5-6 m and the estuary bathymetry amplifies the tidal wave. Its upstream propagation induces a strong mixing of the estuarine waters. The propagation of undular tidal bores was investigated herein to study the effect of bridge piers on the bore propagation and characteristics. Both the tidal bore profile and the turbulence generated by the bore were recorded. The free-surface undulation profiles exhibited a quasi-periodic shape, and the potential energy of the undulations represented up to 30% of the potential energy of the tidal bore. The presence of the channel constriction had a major impact on the free-surface properties. The undular tidal bore lost nearly one third of its potential energy per surface area as it propagated through the channel constriction. The detailed instantaneous velocity measurements showed a marked effect of the tidal bore passage suggesting the upstream advection of energetic events and vorticity "clouds" behind the bore front in both channel configurations: prismatic and with constriction. The turbulence patches were linked to some secondary motions and the proposed mechanisms were consistent with some field observations in the Daly River tidal bore. The findings emphasise the strong mixing induced by the tidal bore processes, and the impact of bridge structures on the phenomenon. © 2010 Springer Science+Business Media B.V

Kin discrimination promotes horizontal gene transfer between unrelated strains in Bacillus subtilis.

This is the final version. Available from Nature Research via the DOI in this record. The data that support the findings of this study are available from the corresponding author upon reasonable request and in Source Data file. Genome sequences are available in the NCBI database under genome accession numbers VBRL00000000, VBRM00000000, VBRN00000000, VBRO00000000, VBRQ00000000 and VBRR00000000. Source data are provided with this paper.Bacillus subtilis is a soil bacterium that is competent for natural transformation. Genetically distinct B. subtilis swarms form a boundary upon encounter, resulting in killing of one of the strains. This process is mediated by a fast-evolving kin discrimination (KD) system consisting of cellular attack and defence mechanisms. Here, we show that these swarm antagonisms promote transformation-mediated horizontal gene transfer between strains of low relatedness. Gene transfer between interacting non-kin strains is largely unidirectional, from killed cells of the donor strain to surviving cells of the recipient strain. It is associated with activation of a stress response mediated by sigma factor SigW in the donor cells, and induction of competence in the recipient strain. More closely related strains, which in theory would experience more efficient recombination due to increased sequence homology, do not upregulate transformation upon encounter. This result indicates that social interactions can override mechanistic barriers to horizontal gene transfer. We hypothesize that KD-mediated competence in response to the encounter of distinct neighbouring strains could maximize the probability of efficient incorporation of novel alleles and genes that have proved to function in a genomically and ecologically similar context.Slovenian Research Agency (ARRS

Suicidality and hostility following involuntary hospital treatment

Background Psychiatric patients showing risk to themselves or others can be involuntarily hospitalised. No data is available on whether following hospitalisation there is a reduction in psychopathological indicators of risk such as suicidality and hostility. This study aimed to assess changes in suicidality and hostility levels following involuntary admission and their patient-level predictors. Methods A pooled analysis of studies on involuntary treatment, including 11 countries and 2790 patients was carried out. Suicidality and hostility were measured by the Brief Psychiatric Rating Scale. Results 2790 patients were included; 2129 followed-up after one month and 1864 after three months. 387 (13.9%) patients showed at least moderate suicidality when involuntarily admitted, 107 (5.0%) after one month and 97 (5.2%) after three months. Moderate or higher hostility was found in 1287 (46.1%) patients after admission, 307 (14.5%) after one month, and 172 (9.2%) after three months. Twenty-three (1.2%) patients showed suicidality, and 53 (2.8%) patients hostility at all time-points. Predictors of suicidality three months after admission were: suicidality at baseline, not having a diagnosis of psychotic disorder and being unemployed. Predictors of hostility were: hostility at baseline, not having a psychotic disorder, living alone, and having been hospitalized previously. Conclusions After involuntary hospital admission, the number of patients with significant levels of suicidality and hostility decreases substantially over time, and very few patients show consistently moderate or higher levels of these symptoms. In patients with psychotic disorders these symptoms are more likely to improve. Social factors such as unemployment and isolation could hamper suicidality and hostility reduction and may be targeted in interventions to reduce risk in involuntarily admitted patients