Comparison of hierarchical temporal memories and artificial neural networks under noisy data

The ability of two different machine learning approaches to map non-linear problems from experimental data is evaluated under controlled experiments. A well-known machine learning algorithm (Artificial Neural Network) is compared against a new computing paradigm (Hierarchical Temporal Memory) under a controlled scenario. The chosen scenario is the detection of impacts in a cantilever beam under vibration instrumented with fiber Bragg gratings. The main characteristics of both of the machine learning approaches are analyzed while varying environmental parameters such as the number of sensing points and their location. From the achieved results some clues can be extracted regarding dealing with noisy or partial data using different machine learning approaches

Sampled Fiber Bragg Grating spectral synthesis

In this paper, a technique to estimate the deformation profile of a Sampled Fiber Bragg Grating (SFBG) is proposed and experimentally verified. From the SFBG intensity reflection spectrum, any arbitrary longitudinal axis deformation profile applied to a SFBG is estimated. The synthesis algorithm combines a custom defined error metric to compare the measured and the synthetic spectra and the Particle Swarm Optimization technique to get the deformation profile. Using controlled deformation profiles, the proposed method has been successfully checked by means of simulated and experimental tests. The results obtained under different controlled cases show a remarkable repetitiveness (< 50 με) and good spatial accuracy (< 1 mm).This work has been supported by the project TEC2010-20224-C02-02 and grant AP2009-1403

Effect of serum phosphate on parathyroid hormone secretion during hemodialysis

Effect of serum phosphate on parathyroid hormone secretion during hemodialysis.BackgroundRecent studies have demonstrated that a high concentration of phosphate directly stimulates parathyroid hormone (PTH) secretion. High serum levels of phosphate are usually observed in patients with end-stage renal disease. The aim of the present study was to evaluate whether serum phosphate concentration had an acute effect on PTH secretion in hemodialysis patients. The levels of serum phosphate were manipulated during the hemodialysis session by using a phosphate free dialysate or a dialysate with a high content of phosphate.MethodsTen stable hemodialysis patients with PTH values above 300 pg/ml were included in the study. A PTH-calcium curve was obtained during both high phosphate and phosphate free hemodialysis.ResultsThe serum phosphate concentration remained high (2.17 ± 0.18mM) throughout the high phosphate hemodialysis and decreased progressively to normal levels (1.02 ± 0.06mM) during the phosphate free hemodialysis. The serum PTH levels at maximal inhibition by hypercalcemia (minimal PTH) were greater during the high phosphate than the phosphate free hemodialysis (413 ± 79 vs. 318 ± 76 pg/ml, P < 0.003). In all patients the values of minimum PTH were greater during the high phosphorus than the phosphorus free hemodialysis. The values of maximally stimulated PTH during hypocalcemia and the set point of the PTH-calcium curve were similar during the high phosphate and the phosphate free hemodialysis.ConclusionThe maintenance of high serum phosphorus levels during hemodialysis prevented, in part, the inhibition of PTH secretion by calcium, which strongly suggests that in hemodialysis patients high serum phosphate contributes directly to the elevation of PTH levels despite normal or high serum calcium concentration

Wavelength-switchable L-band fiber laser assisted by random reflectors

A wavelength-switchable L-band erbium-doped fiber laser (EDFL) assisted by an artificially controlled backscattering (ACB) fiber reflector is here presented. This random reflector was inscribed by femtosecond (fs) laser direct writing on the axial axis of a multimode fiber with 50 μm core and 125 μm cladding with a length of 17 mm. This microstructure was placed inside a surgical syringe to be positioned in the center of a high-precision rotation mount to accurately control its angle of rotation. Only by rotating this mount, three different output spectra were obtained: a single wavelength lasing centered at 1574.75 nm, a dual wavelength lasing centered at 1574.75 nm and 1575.75 nm, and a single wavelength lasing centered at 1575.5 nm. All of them showed an optical signal-to-noise ratio (OSNR) of around 60 dB when pumped at 300 mW

Impact of dapagliflozin on cardiac remodelling in patients with chronic heart failure: The DAPA-MODA study.

AIMS Dapagliflozin improves the prognosis of patients with heart failure (HF), regardless of left ventricular ejection fraction (LVEF). However, its effect on cardiac remodelling parameters, specifically left atrial (LA) remodelling, is not well established. METHODS AND RESULTS The DAPA-MODA trial (NCT04707352) is a multicentre, single-arm, open-label, prospective and interventional study that aimed to evaluate the effect of dapagliflozin on cardiac remodelling parameters over 6 months. Patients with stable chronic HF receiving optimized guideline-directed therapy, except for any sodium-glucose cotransporter 2 inhibitor, were included. Echocardiography was performed at baseline, 30 and 180 days, and analysed by a central core-lab in a blinded manner to both patient and time. The primary endpoint was the change in maximal LA volume index (LAVI). A total of 162 patients (64.2% men, 70.5 ± 10.6 years, 52% LVEF >40%) were included in the study. At baseline, LA dilatation was observed (LAVI 48.1 ± 22.6 ml/m2 ) and LA parameters were similar between LVEF-based phenotypes (≤40% vs. >40%). LAVI showed a significant reduction at 180 days (-6.6% [95% confidence interval -11.1, -1.8], p = 0.008), primarily due to a decrease in reservoir volume (-13.8% [95% confidence interval -22.5, -4], p = 0.007). Left ventricular geometry improved with significant reductions in left ventricular mass index (-13.9% [95% confidence interval -18.7, -8.7], p < 0.001), end-diastolic volume (-8.0% [95% confidence interval -11.6, -4.2], p < 0.001) and end-systolic volume (-11.9% [95% confidence interval -16.7, -6.8], p < 0.001) at 180 days. N-terminal pro-B-type natriuretic peptide (NT-proBNP) showed a significant reduction at 180 days (-18.2% [95% confidence interval -27.1, -8.2], p < 0.001), without changes in filling Doppler measures. CONCLUSION Dapagliflozin administration in stable out-setting patients with chronic HF and optimized therapy results in global reverse remodelling of cardiac structure, including reductions in LA volumes and improvement in left ventricular geometry and NT-proBNP concentrations.This study has been sponsored by Sociedad Española de Cardiología and has received funding by a non-conditional investigational grant from AstraZeneca Farmacéutica Spain.S

Antibióticos empíricos para la neumonía adquirida en la comunidad en pacientes adultos: Una revisión sistemática y un metaanálisis en red

Objetivo: El objetivo principal de este metaanálisis en red es identificar el antibiótico empírico (Em-ATB) con mayor probabilidad de ser el mejor (HPBB) en términos de (1) tasa de curación y (2) tasa de mortalidad en pacientes hospitalizados con neumonía adquirida en la comunidad (NAC) . Método: Criterios de inclusión: (1) pacientes adultos (>16 años) diagnosticados de NAC que requirieron hospitalización; (2) aleatorizados a al menos dos Em-ATB diferentes, (3) que informen de la tasa de curación y (4) que estén escritos en inglés o español. Criterios de exclusión: (1) protocolo de antibióticos ambiguo y (2) publicados exclusivamente en formato resumen o carta. Fuentes de datos: Medline, Embase, Cochrane y revisiones de citas desde el 1 de enero de 2000 hasta el 31 de diciembre de 2018. Riesgo de sesgo: Herramienta de Cochrane. Calidad de la revisión sistemática (RS): A MeaSurement Tool to Assess systematic Reviews-2. Certeza de la evidencia: Grading of Recommendations Assessment, Development and Evaluation. Análisis estadísticos: método frecuentista realizado con la biblioteca 'netmeta', paquete R. Resultados: se incluyeron 27 ensayos controlados aleatorizados (ECA) de las 41.307 citas seleccionadas inicialmente. En cuanto al riesgo de sesgo, más de una cuarta parte de los estudios presentaron riesgo bajo y ningún estudio presentó riesgo alto en todos los dominios. La calidad de la RS es moderada. Para la curación, se construyeron dos redes. Así, dos Em-ATB tienen la HPBB: cetarolina 600 mg (dos veces al día) y piperacilina 2000 mg (dos veces al día). Para la mortalidad, se construyeron tres redes. Así, tres Em-ATB tienen la HPBB: ceftriaxona 2000 mg (una vez al día) más levofloxacino 500 (dos veces al día), ertapenem 1000 mg (dos veces al día) y amikacina 250 mg (dos veces al día) más claritromicina 500 mg (dos veces al día). La certeza de la evidencia para cada resultado es moderada. Conclusiones: Para la tasa de curación, ceftarolina y piperacilina son las opciones con la HPBB. Sin embargo, para la tasa de mortalidad, las opciones son ceftriaxona más levofloxacino, ertapenem y amikacina más claritromicina. Parece necesario realizar un ECA que compare los tratamientos con el HPBB para cada evento (curación o mortalidad) (CRD42017060692).Objective: The main aim of this network meta-analysis is to identify the empiric antibiotic (Em-ATB) with the highest probability of being the best (HPBB) in terms of (1) cure rate and (2) mortality rate in hospitalised patients with community acquired pneumonia (CAP) . Method: Inclusion criteria: (1) adult patients (>16 years old) diagnosed with CAP that required hospitalisation; (2) randomised to at least two different Em-ATBs, (3) that report cure rate and (4) are written in English or Spanish. Exclusion criteria: (1) ambiguous antibiotics protocol and (2) published exclusively in abstract or letter format. Data sources: Medline, Embase, Cochrane and citation reviews from 1 January 2000 to 31 December 2018. Risk of bias: Cochrane's tool. Quality of the systematic review (SR): A MeaSurement Tool to Assess systematic Reviews-2. Certainity of the evidence: Grading of Recommendations Assessment, Development and Evaluation. Statistical analyses: frequentist method performed with the 'netmeta' library, R package. Results: 27 randomised controlled trials (RCTs) from the initial 41 307 screened citations were included. Regarding the risk of bias, more than one quarter of the studies presented low risk and no study presented high risk in all domains. The SR quality is moderate. For cure, two networks were constructed. Thus, two Em-ATBs have the HPBB: cetaroline 600 mg (two times a day) and piperacillin 2000 mg (two times a day). For mortality, three networks were constructed. Thus, three Em-ATBs have the HPBB: ceftriaxone 2000 mg (once a day) plus levofloxacin 500 (two times a day), ertapenem 1000 mg (two times a day) and amikacin 250 mg (two times a day) plus clarithromycin 500 mg (two times a day). The certainity of evidence for each results is moderate. Conclusion: For cure rate, ceftaroline and piperaciline are the options with the HPBB. However, for mortality rate, the options are ceftriaxone plus levofloxacin, ertapenem and amikacin plus clarithromycin. It seems necessary to conduct an RCT that compares treatments with the HPBB for each event (cure or mortality) (CRD42017060692)

The efficacy of suppressive antibiotic treatment in patients managed non-operatively for periprosthetic joint infection and a draining sinus

Objectives: Patients with prosthetic joint infections (PJIs) not suitable for curative surgery may benefit from suppressive antibiotic therapy (SAT). However, the usefulness of SAT in cases with a draining sinus has never been investigated. Methods: A multicentre, retrospective observational cohort study was performed in which patients with a PJI and a sinus tract were eligible for inclusion if managed conservatively and if sufficient follow-up data were available (i.e. at least 2 years). SAT was defined as a period of &gt; 6 months of oral antibiotic therapy. Results: SAT was initiated in 63 of 72 (87.5 %) included patients. Implant retention during follow-up was the same in patients receiving SAT vs. no SAT (79.4 % vs. 88.9 %; pCombining double low line0.68). In total, 27 % of patients using SAT experienced side effects. In addition, the occurrence of prosthetic loosening in initially fixed implants, the need for surgical debridement, or the occurrence of bacteremia during follow-up could not be fully prevented with the use of SAT, which still occurred in 42 %, 6.3 %, and 3.2 % of cases, respectively. However, the sinus tract tended to close more often (42 % vs. 13 %; pCombining double low line0.14), and a higher resolution of pain was observed (35 % vs. 14 %; pCombining double low line0.22) in patients receiving SAT. Conclusions: SAT is not able to fully prevent complications in patients with a draining sinus. However, it may be beneficial in a subset of patients, particularly in those with pain or the hindrance of a draining sinus. A future prospective study, including a higher number of patients not receiving SAT, is needed

Potential group B Streptococcus interspecies transmission between cattle and people in Colombian dairy farms

Group B Streptococcus (GBS), is a leading cause of neonatal death and an emerging pathogen in adults. Additionally, GBS is a bovine pathogen causing intramammary infections. The likelihood of GBS interspecies transmission is largely unknown. We explored the potential transmission of GBS between cattle and people on dairy farms in Colombia and compared the antimicrobial resistance (AMR) profiles of isolates from both host species. Across 33 farms, throat swabs and rectal swabs were collected from 191 people, and rectal swabs and composite milk samples from 2092 cattle, yielding 60 human isolates and 301 bovine isolates. The majority (64%) of isolates belonged to shared sequence types (ST). Sequence type (ST) 1 was the most common strain in both host species, suggesting that interspecies transmission may be possible. Two members of the bovine-specific clonal complex 61/67 were detected in human samples (ST718 and ST1175), providing evidence for the lack of genuine species barriers. Apparent prevalence of penicillin resistance was surprisingly high in human and bovine isolates. Further investigation of this phenomenon is needed and could lead to modification of standard testing and treatment recommendations in human and veterinary medicine

First observation of Bs -> D_{s2}^{*+} X mu nu decays

Using data collected with the LHCb detector in proton-proton collisions at a centre-of-mass energy of 7 TeV, the semileptonic decays Bs -> Ds+ X mu nu and Bs -> D0 K+ X mu nu are detected. Two structures are observed in the D0 K+ mass spectrum at masses consistent with the known D^+_{s1}(2536) and $D^{*+}_{s2}(2573) mesons. The measured branching fractions relative to the total Bs semileptonic rate are B(Bs -> D_{s2}^{*+} X mu nu)/B(Bs -> X mu nu)= (3.3\pm 1.0\pm 0.4)%, and B(Bs -> D_{s1}^+ X munu)/B(Bs -> X mu nu)= (5.4\pm 1.2\pm 0.5)%, where the first uncertainty is statistical and the second is systematic. This is the first observation of the D_{s2}^{*+} state in Bs decays; we also measure its mass and width.Comment: 8 pages 2 figures. Published in Physics Letters