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1.
Int J Biol Macromol ; 253(Pt 7): 127488, 2023 Dec 31.
Article in English | MEDLINE | ID: mdl-37852395

ABSTRACT

Herein, biobased composite materials based on poly(lactic acid) (PLA) and poly(butylene adipate-co-terephthalate) (PBAT) as matrices, sodium hexametaphosphate microparticles (E452i, food additive microparticles, 1 and 5 wt%) as antimicrobial filler and acetyl tributyl citrate (ATBC, 15 wt%) as plasticizer, were developed for potential food packaging applications. Two set of composite films were obtained by melt-extrusion and compression molding, i) based on PLA matrix and ii) based on Ecovio® matrix (PLA/PBAT blend). Thermal characterization by thermogravimetric analysis and differential scanning calorimetry demonstrated that the incorporation of E452i particles improved thermal stability and crystallinity, while the mechanical test showed an increase in the Young's modulus. E452i particles also provide antimicrobial properties to the films against food-borne bacteria Listeria innocua and Staphylococcus aureus, with bacterial reduction percentages higher than 50 % in films with 5 wt% of particles. The films also preserved their disintegradability as demonstrated by an exhaustive characterization of the films under industrial composting conditions. Therefore, the results obtained in this work reveal the potential of these biocomposites as appropriated materials for antibacterial and compostable food packaging films.


Subject(s)
Food Packaging , Polyesters , Polyesters/chemistry , Food Packaging/methods , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry
2.
Hum Resour Health ; 21(1): 70, 2023 08 24.
Article in English | MEDLINE | ID: mdl-37620869

ABSTRACT

BACKGROUND: There is a growing interest in understanding the impact of duty hours and resting times on training outcomes and the well-being of resident physicians. However, to this date no state-wide analysis exists in any European country. OBJECTIVES: Our aim is to describe the shift work scheduling and to detail the degree of compliance with the Spanish legislation and the European Working Time Directive (EWTD) of Spanish resident physicians, focusing on territorial and specialty distribution. MATERIAL AND METHODS: A descriptive cross-sectional analytical study was designed through an online survey adapted from the existing literature. RESULTS: Out of the 2035 surveyed resident physicians undergoing PGT in Spain, 80.49% exceeded the 48 h per week limit set by the EWTD and 13% of them did not rest after a 24-h on-call shift. The mean number of on-call shifts in the last 3 months was 15.03, with the highest mean reported in Asturias, La Rioja, and Extremadura. 51.6% of respondents had a day-off after a Saturday on-call shift. Significant differences are observed by region and type of specialty. CONCLUSION: Resident physicians in Spain greatly exceed the established 48 h/week EWTD limit. Likewise, non-compliance with labor regulations regarding mandatory rest after on-call duty and minimum weekly rest periods are observed.


Subject(s)
Physicians , Humans , Spain , Cross-Sectional Studies , Europe , Time Factors
3.
Ultrasound Obstet Gynecol ; 61(3): 399-407, 2023 03.
Article in English | MEDLINE | ID: mdl-35802514

ABSTRACT

OBJECTIVES: To evaluate the reproducibility of lower uterine segment (LUS) thickness measurement before induction of labor (IOL), and to assess the relationship between LUS thickness and IOL outcomes. METHODS: This was a prospective cohort study of pregnant women undergoing IOL at term, conducted in a single tertiary hospital between July 2014 and February 2017. Women with a singleton pregnancy at ≥ 37 weeks' gestation, with a live fetus in cephalic presentation and a Bishop score of ≤ 6, were eligible for inclusion. Both nulliparous and parous women, and those with a previous Cesarean section (CS), were eligible. All women underwent transvaginal ultrasound assessment before IOL admission, and cervical length and LUS thickness were measured offline after delivery. Maternal and obstetric characteristics and Bishop score were recorded. The main outcome was the overall rate of CS after IOL, and secondary outcomes were CS for either failure to progress in the active phase of labor or failed IOL, and CS for failed IOL only. Interobserver agreement for measurement of LUS thickness between two operators was assessed using the intraclass correlation coefficient (ICC) and Bland-Altman analysis with the ANOVA test to evaluate systematic bias. Univariable and multivariable analysis were employed to evaluate the relationship between clinical and sonographic characteristics and IOL outcomes. RESULTS: Of 265 women included in the analysis, 195 (73.6%) had a vaginal delivery and 70 (26.4%) required a CS after IOL. Reproducibility analysis showed excellent interobserver agreement for the measurement of LUS thickness (ICC, 0.96 (95% CI, 0.93-0.98)). On Bland-Altman analysis, the mean difference in LUS thickness between the two operators was 0.15 mm (95% limits of agreement, -1.84 to 2.14 mm), and there was no evidence of systematic bias (ANOVA test, P = 0.46). Univariable analysis showed that LUS thickness was associated significantly with overall CS (P = 0.002), CS for failure to progress in the active phase of labor or failed IOL (P = 0.03) and CS for failed IOL (P = 0.037). On multivariable logistic regression analysis, LUS thickness was an independent predictive factor for overall CS (odds ratio (OR), 1.149 (95% CI, 1.031-1.281)) and CS for failure to progress in the active phase of labor or failed IOL (OR, 1.226 (95% CI, 1.039-1.445)). CONCLUSIONS: In women undergoing IOL at term, measurement of LUS thickness is feasible and reproducible, and is associated significantly with IOL outcome. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.


Subject(s)
Cesarean Section , Ultrasonography, Prenatal , Pregnancy , Female , Humans , Prospective Studies , Reproducibility of Results , Labor, Induced
4.
Ultrasound Obstet Gynecol ; 59(6): 793-798, 2022 06.
Article in English | MEDLINE | ID: mdl-34542928

ABSTRACT

OBJECTIVES: Cervical length (CL) measurement ≤ 25 mm on mid-trimester ultrasound scan is a known risk factor for preterm birth, for which vaginal progesterone is recommended. The aims of this study were to evaluate whether CL measurement is affected by observer bias and to assess the impact on short cervix prevalence of masking CL measurement during routine mid-trimester ultrasound scan. METHODS: This was a flash study designed for a 2-month period (October and November 2018) at Cruces University Hospital (Bizkaia, Spain), in which all CL measurements from routine mid-trimester scans were masked. During the study period, there was no modification of the routine screening method, and women with a short cervix were prescribed 200 mg vaginal progesterone daily as per usual. The control group included women examined in a 2-month period (April and May 2018) prior to the study, in which CL measurements were taken as usual by a non-blinded operator. The primary outcome was the prevalence of short cervix in each group. RESULTS: A total of 983 CL measurements were analyzed, including 457 in the blinded group and 526 in the control group. The prevalence of short cervix was 2.7% in the non-blinded group and 5.5% in the blinded group (P = 0.024). We identified a statistically significant difference in the incidence of CL of 24-25 mm between the two groups, with a lower prevalence in the non-blinded vs blinded group (0.6% vs 2.4%; P < 0.005). Moreover, the distribution of CL values was normal in the blinded group, in contrast to the non-blinded group, which was characterized by skewed distribution of CL values. CONCLUSIONS: Expected-value bias exists and should be taken into account when measuring CL in mid-trimester preterm birth screening. Blinding has demonstrated to be an effective strategy to improve the performance of CL screening in clinical practice. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.


Subject(s)
Premature Birth , Cervical Length Measurement/methods , Cervix Uteri/diagnostic imaging , Female , Humans , Infant, Newborn , Pregnancy , Pregnancy Trimesters , Premature Birth/epidemiology , Progesterone
5.
Ultrasound Obstet Gynecol ; 57(2): 257-265, 2021 02.
Article in English | MEDLINE | ID: mdl-33142361

ABSTRACT

OBJECTIVES: First, to validate a previously developed model for screening for pre-eclampsia (PE) by maternal characteristics and medical history in twin pregnancies; second, to compare the distributions of mean arterial pressure (MAP), uterine artery pulsatility index (UtA-PI), serum placental growth factor (PlGF) and serum pregnancy-associated plasma protein-A (PAPP-A) in twin pregnancies that delivered with PE to those in singleton pregnancies and to develop new models based on these results; and, third, to examine the predictive performance of these models in screening for PE with delivery at < 32 and < 37 weeks' gestation. METHODS: Two datasets of prospective non-intervention multicenter screening studies for PE in twin pregnancies at 11 + 0 to 13 + 6 weeks' gestation were used. The first dataset was from the EVENTS (Early vaginal progesterone for the preVention of spontaneous prEterm birth iN TwinS) trial and the second was from a previously reported study that examined the distributions of biomarkers in twin pregnancies. Maternal demographic characteristics and medical history from the EVENTS-trial dataset were used to assess the validity of risks from our previously developed model. The combined data from the first and second datasets were used to compare the distributional properties of log10 multiples of the median (MoM) values of UtA-PI, MAP, PlGF and PAPP-A in twin pregnancies that delivered with PE to those in singleton pregnancies and develop new models based on these results. The competing-risks model was used to estimate the individual patient-specific risks of delivery with PE at < 32 and < 37 weeks' gestation. Screening performance was measured by detection rates (DR) and areas under the receiver-operating-characteristics curve. RESULTS: The EVENTS-trial dataset comprised 1798 pregnancies, including 168 (9.3%) that developed PE. In the validation of the prior model based on maternal characteristics and medical history, calibration plots demonstrated very good agreement between the predicted risks and the observed incidence of PE (calibration slope and intercept for PE < 32 weeks were 0.827 and 0.009, respectively, and for PE < 37 weeks they were 0.942 and -0.207, respectively). In the combined data, there were 3938 pregnancies, including 339 (8.6%) that developed PE and 253 (6.4%) that delivered with PE at < 37 weeks' gestation. In twin pregnancies that delivered with PE, MAP, UtA-PI and PlGF were, at earlier gestational ages, more discriminative than in singleton pregnancies and at later gestational ages they were less so. For PAPP-A, there was little difference between PE and unaffected pregnancies. The best performance of screening for PE was achieved by a combination of maternal factors, MAP, UtA-PI and PlGF. In screening by maternal factors alone, the DR, at a 10% false-positive rate, was 30.6% for delivery with PE at < 32 weeks' gestation and this increased to 86.4% when screening by the combined test; the respective values for PE < 37 weeks were 24.9% and 41.1%. CONCLUSIONS: In the assessment of risk for PE in twin pregnancy, we can use the same prior model based on maternal characteristics and medical history as reported previously, but in the calculation of posterior risks it is necessary to use the new distributions of log10 MoM values of UtA-PI, MAP and PlGF according to gestational age at delivery with PE. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.


Subject(s)
Pre-Eclampsia/diagnosis , Prenatal Diagnosis , Uterine Artery/physiology , Biomarkers/blood , Blood Flow Velocity , Europe , Female , Gestational Age , Humans , Placenta Growth Factor/blood , Pre-Eclampsia/blood , Pre-Eclampsia/physiopathology , Predictive Value of Tests , Pregnancy , Pregnancy, Twin , Pregnancy-Associated Plasma Protein-A/metabolism , Prospective Studies , Pulsatile Flow , Uterine Artery/diagnostic imaging
6.
Phys Rev Lett ; 125(22): 220602, 2020 Nov 27.
Article in English | MEDLINE | ID: mdl-33315444

ABSTRACT

We introduce a model of trapped bosons with contact interactions as well as Coulomb repulsion or gravitational attraction in one spatial dimension. We find the exact ground-state energy and many-body wave function. The density profile and the pair-correlation function are sampled using Monte Carlo method and show a rich variety of regimes with crossovers between them. Strong attraction leads to a trapped McGuire quantum soliton. Weak repulsion results in an incompressible Laughlin-like fluid with flat density, well reproduced by a Gross-Pitaevskii equation with long-range interactions. Stronger repulsion induces Friedel oscillations and the eventual formation of a Wigner crystal.

7.
Phys Rev Lett ; 122(8): 080604, 2019 Mar 01.
Article in English | MEDLINE | ID: mdl-30932622

ABSTRACT

In the nonadiabatic dynamics across a quantum phase transition, the Kibble-Zurek mechanism predicts that the formation of topological defects is suppressed as a universal power law with the quench time. In inhomogeneous systems, the critical point is reached locally and causality reduces the effective system size for defect formation to regions where the velocity of the critical front is slower than the sound velocity, favoring adiabatic dynamics. The reduced density of excitations exhibits a much steeper dependence on the quench rate and is also described by a universal power law that we demonstrated in a quantum Ising chain.

8.
RSC Adv ; 9(31): 17571-17580, 2019 Jun 04.
Article in English | MEDLINE | ID: mdl-35520560

ABSTRACT

The purpose of this work is to fabricate self-assembled microstructures by the sol-gel method and study the morphological, structural and compositional dependence of ε-Fe2O3 nanoparticles embedded in silica when glycerol (GLY) and cetyl-trimethylammonium bromide (CTAB) are added as steric agents simultaneously. The combined action of a polyalcohol and a surfactant significantly modifies the morphology of the sample giving rise to a different microstructure in each of the studied cases (1, 3 and 7 days of magnetic stirring time). This is due to the fact that the addition of these two compounds leads to a considerable increase in gelation time as GLY can interact with the alkoxide group on the surface of the iron oxide precursor micelle and/or be incorporated into the hydrophilic chains of CTAB. This last effect causes the iron oxide precursor micelles to be interconnected forming aggregates whose size and structure depend on the magnetic stirring time of the sol-gel synthetic route. In this paper, crystalline structure, composition, purity and morphology of the sol-gel coatings densified at 960 °C are examined. Emphasis is placed on the nominal percentage of the different iron oxides found in the samples and on the morphological and structural differences. This work implies the possibility of patterning ε-Fe2O3 nanoparticles in coatings and controlling their purity by an easy one-pot sol-gel method.

9.
Sci Rep ; 8(1): 12634, 2018 Aug 22.
Article in English | MEDLINE | ID: mdl-30135459

ABSTRACT

A universal relation is established between the quantum work probability distribution of an isolated driven quantum system and the Loschmidt echo dynamics of a two-mode squeezed state. When the initial density matrix is canonical, the Loschmidt echo of the purified double thermofield state provides a direct measure of information scrambling and can be related to the analytic continuation of the partition function. Information scrambling is then described by the quantum work statistics associated with the time-reversal operation on a single copy, associated with the sudden negation of the system Hamiltonian.

10.
Phys Rev Lett ; 120(16): 160403, 2018 Apr 20.
Article in English | MEDLINE | ID: mdl-29756911

ABSTRACT

We introduce an exact mapping between the Dirac equation in (1+1)-dimensional curved spacetime (DCS) and a multiphoton quantum Rabi model (QRM). A background of a (1+1)-dimensional black hole requires a QRM with one- and two-photon terms that can be implemented in a trapped ion for the quantum simulation of Dirac particles in curved spacetime. We illustrate our proposal with a numerical analysis of the free fall of a Dirac particle into a (1+1)-dimensional black hole, and find that the Zitterbewegung effect, measurable via the oscillatory trajectory of the Dirac particle, persists in the presence of gravity. From the duality between the squeezing term in the multiphoton QRM and the metric coupling in the DCS, we show that gravity generates squeezing of the Dirac particle wave function.

11.
Phys Rev Lett ; 120(7): 070401, 2018 Feb 16.
Article in English | MEDLINE | ID: mdl-29542956

ABSTRACT

Quantum speed limits set an upper bound to the rate at which a quantum system can evolve. Adopting a phase-space approach, we explore quantum speed limits across the quantum-to-classical transition and identify equivalent bounds in the classical world. As a result, and contrary to common belief, we show that speed limits exist for both quantum and classical systems. As in the quantum domain, classical speed limits are set by a given norm of the generator of time evolution.

12.
Radiología (Madr., Ed. impr.) ; 60(1): 64-72, ene.-feb. 2018. tab, ilus
Article in Spanish | IBECS | ID: ibc-170438

ABSTRACT

Objetivo. Comprobar si es posible determinar el grado de resección de macroadenomas hipofisarios en la resonancia magnética (RM) hipofisaria posquirúrgica inmediata. Material y métodos. Se revisaron las RM hipofisarias de pacientes intervenidos desde enero de 2010 hasta octubre de 2014. Se incluyeron aquellos que tenían RM diagnóstica, RM posquirúrgica inmediata y al menos un control posterior. Se comprobó si los hallazgos entre la RM posquirúrgica inmediata y las RM posteriores eran concordantes. Se excluyeron los casos sin controles evolutivos y las reintervenciones por recidivas. El grado de resección tumoral lo dividimos en grupos: resección total, resección parcial y dudoso. Los estudios se realizaron en una máquina de 1.5 Tesla siguiendo el mismo protocolo de secuencias: una parte morfológica, otra dinámica con contraste intravenoso y otra con contraste tardío. Resultados. De 73 casos incluidos, la RM posquirúrgica inmediata se interpretó como resección total en 38 casos y resto tumoral en 28 casos, habiendo dudas en 7 casos. En los controles evolutivos se determinó resección total en 41 casos y resto tumoral en 32. Se obtuvo una sensibilidad para detección de restos tumorales de 0,71, una especificidad de 0,82, un valor predictivo positivo de 0,89 y un valor predictivo negativo de 0,85 en la RM posquirúrgica inmediata respecto a los controles evolutivos. Conclusión. La RM posquirúrgica inmediata de macroadenomas hipofisarios es útil para valorar el grado de resección tumoral y es un buen predictor del grado de resección real definitivo al comparar con las RM posteriores, permitiendo plantear el tratamiento adecuado de forma precoz (AU)


Objective. To evaluate if it is possible to determine the extent of pituitary macroadenomas resection in the immediate postoperative pituitary magnetic resonance imaging (MRI). Material and methods. MRI of patient with pituitary macroadenomas from January 2010 until October 2014 were reviewed. Those patients who had diagnostic MRI, immediate post-surgical MRI and at least one MRI control were included. We evaluate if the findings between the immediate postsurgical MRI and the subsequent MRI were concordant. Cases which didn’t have evolutionary controls and those who were reoperation for recurrence were excluded. The degree of tumor resection was divided into groups: total resection, partial resection and doubtful. All MRI studies were performed on a1.5T machine following the same protocol sequences for all cases. One morphological part, a dynamic contrast iv and late contrast part. Results. Of the 73 cases included, immediate postoperative pituitary MRI was interpreted as total resection in 38 cases and tumoral rest in 28 cases, uncertainty among rest or inflammatory changes in 7 cases. Follow- up MRI identified 41 cases total resection and tumoral rest in 32. Sensitivity and specificity of 0.78 and 0.82 and positive and negative predictive value (PPV and NPV) 0.89 and 0.89 respectively were calculated. Conclusion. Immediate post-surgery pituitary MRI is useful for assessing the degree of tumor resection and is a good predictor of the final degree of real resection compared with the following MRI studies. It allows us to decide the most appropriate treatment at an early stage (AU)


Subject(s)
Humans , Prolactinoma/surgery , Pituitary Neoplasms/surgery , Magnetic Resonance Imaging/methods , Margins of Excision , Neoplasm, Residual/diagnostic imaging , Postoperative Complications/diagnostic imaging , Neoplasm Recurrence, Local/diagnostic imaging , Postoperative Care/methods
13.
Radiologia (Engl Ed) ; 60(1): 64-72, 2018.
Article in English, Spanish | MEDLINE | ID: mdl-29179978

ABSTRACT

OBJECTIVE: To evaluate if it is possible to determine the extent of pituitary macroadenomas resection in the immediate postoperative pituitary magnetic resonance imaging (MRI). MATERIAL AND METHODS: MRI of patient with pituitary macroadenomas from January 2010 until October 2014 were reviewed. Those patients who had diagnostic MRI, immediate post-surgical MRI and at least one MRI control were included. We evaluate if the findings between the immediate postsurgical MRI and the subsequent MRI were concordant. Cases which didn't have evolutionary controls and those who were reoperation for recurrence were excluded. The degree of tumor resection was divided into groups: total resection, partial resection and doubtful. All MRI studies were performed on a1.5T machine following the same protocol sequences for all cases. One morphological part, a dynamic contrast iv and late contrast part. RESULTS: Of the 73 cases included, immediate postoperative pituitary MRI was interpreted as total resection in 38 cases and tumoral rest in 28 cases, uncertainty among rest or inflammatory changes in 7 cases. Follow- up MRI identified 41 cases total resection and tumoral rest in 32. Sensitivity and specificity of 0.78 and 0.82 and positive and negative predictive value (PPV and NPV) 0.89 and 0.89 respectively were calculated. CONCLUSION: Immediate post-surgery pituitary MRI is useful for assessing the degree of tumor resection and is a good predictor of the final degree of real resection compared with the following MRI studies. It allows us to decide the most appropriate treatment at an early stage.


Subject(s)
Adenoma/diagnostic imaging , Adenoma/surgery , Pituitary Neoplasms/diagnostic imaging , Pituitary Neoplasms/surgery , Adenoma/pathology , Adult , Aged , Aged, 80 and over , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Pituitary Neoplasms/pathology , Postoperative Care , Retrospective Studies , Surgical Procedures, Operative/methods , Time Factors , Young Adult
14.
J Phys Condens Matter ; 29(48): 485701, 2017 12 06.
Article in English | MEDLINE | ID: mdl-29116941

ABSTRACT

The current study unveils the structural origin of the magnetic transition of the ε-Fe2O3 polymorph from an incommensurate magnetic order to a collinear ferrimagnetic state at low temperature. The high crystallinity of the samples and the absence of other iron oxide polymorphs have allowed us to carry out temperature-dependent x-ray absorption fine structure spectroscopy experiments out. The deformation of the structure is followed by the Debye-Waller factor for each selected Fe-O and Fe-Fe sub-shell. For nanoparticle sizes between 7 and 15 nm, the structural distortions between the Fete and Fe-D1oc sites are localized in a temperature range before the magnetic transition starts. On the contrary, the inherent interaction between the other sub-shells (named Fe-O1,2 and Fe-Fe1) provokes cooperative magneto-structural changes in the same temperature range. This means that the Fete with Fe-D1oc polyhedron interaction seems to be uncoupled with temperature dealing with these nanoparticle sizes wherein the structural distortions are likely moderate due to surface effects.

15.
Phys Rev Lett ; 119(1): 010403, 2017 Jul 07.
Article in English | MEDLINE | ID: mdl-28731775

ABSTRACT

We introduce general bounds for the parameter estimation error in nonlinear quantum metrology of many-body open systems in the Markovian limit. Given a k-body Hamiltonian and p-body Lindblad operators, the estimation error of a Hamiltonian parameter using a Greenberger-Horne-Zeilinger state as a probe is shown to scale as N^{-[k-(p/2)]}, surpassing the shot-noise limit for 2k>p+1. Metrology equivalence between initial product states and maximally entangled states is established for p≥1. We further show that one can estimate the system-environment coupling parameter with precision N^{-(p/2)}, while many-body decoherence enhances the precision to N^{-k} in the noise-amplitude estimation of a fluctuating k-body Hamiltonian. For the long-range Ising model, we show that the precision of this parameter beats the shot-noise limit when the range of interactions is below a threshold value.

16.
Phys Rev Lett ; 118(14): 140403, 2017 Apr 07.
Article in English | MEDLINE | ID: mdl-28430494

ABSTRACT

We introduce a scheme for the quantum simulation of many-body decoherence based on the unitary evolution of a stochastic Hamiltonian. Modulating the strength of the interactions with stochastic processes, we show that the noise-averaged density matrix simulates an effectively open dynamics governed by k-body Lindblad operators. Markovian dynamics can be accessed with white-noise fluctuations; non-Markovian dynamics requires colored noise. The time scale governing the fidelity decay under many-body decoherence is shown to scale as N^{-2k} with the system size N. Our proposal can be readily implemented in a variety of quantum platforms including optical lattices, superconducting circuits, and trapped ions.

17.
Langmuir ; 33(11): 2872-2877, 2017 03 21.
Article in English | MEDLINE | ID: mdl-28247766

ABSTRACT

Herein, we propose a strategy to fabricate core-shell microstructures ordered in hexagonal arrays by combining the breath figures approach and phase separation of immiscible ternary blends. This simple strategy to fabricate these structures involves only the solvent casting of a ternary polymer blend under moist atmosphere, which provides a facile and low-cost fabrication method to obtain the porous structures with a core-shell morphology. For this purpose, blends consisting of polystyrene (PS) as a major component and PS40-b-P(PEGMA300)48 amphiphilic copolymer and polydimethylsiloxane (PDMS) as minor components were dissolved in tetrahydrofuran and cast onto glass wafers under humid conditions, 70% of relative humidity. The resulting porous morphologies were characterized by optical and confocal Raman microscopy. In particular, confocal Raman results demonstrated the formation of core-shell morphologies into the ordered pores, in which the PS forms the continuous matrix, whereas the other two phases are located into the cavities (PDMS is the core while the amphiphilic copolymer is the shell). Besides, by controlling the weight ratio of the polymer blends, the structural parameters of the porous structure such as pore diameter and the size of the core can be effectively tuned.

18.
Science ; 355(6325)2017 02 10.
Article in English | MEDLINE | ID: mdl-28183913

ABSTRACT

The human microbiome encodes vast numbers of uncharacterized enzymes, limiting our functional understanding of this community and its effects on host health and disease. By incorporating information about enzymatic chemistry into quantitative metagenomics, we determined the abundance and distribution of individual members of the glycyl radical enzyme superfamily among the microbiomes of healthy humans. We identified many uncharacterized family members, including a universally distributed enzyme that enables commensal gut microbes and human pathogens to dehydrate trans-4-hydroxy-l-proline, the product of the most abundant human posttranslational modification. This "chemically guided functional profiling" workflow can therefore use ecological context to facilitate the discovery of enzymes in microbial communities.


Subject(s)
Gastrointestinal Microbiome/genetics , Gastrointestinal Tract/microbiology , Hydroxyproline/metabolism , Proline Oxidase/chemistry , Proline Oxidase/genetics , Amino Acid Motifs , Anaerobiosis , Humans , Metagenome , Proline Oxidase/metabolism , Propanediol Dehydratase/chemistry , Propanediol Dehydratase/genetics , Protein Processing, Post-Translational , Sequence Alignment
19.
Phys Rev Lett ; 119(13): 130401, 2017 Sep 29.
Article in English | MEDLINE | ID: mdl-29341721

ABSTRACT

A system prepared in an unstable quantum state generally decays following an exponential law, as environmental decoherence is expected to prevent the decay products from recombining to reconstruct the initial state. Here we show the existence of deviations from exponential decay in open quantum systems under very general conditions. Our results are illustrated with the exact dynamics under quantum Brownian motion and suggest an explanation of recent experimental observations.

20.
Phys Rev Lett ; 119(4): 040501, 2017 Jul 28.
Article in English | MEDLINE | ID: mdl-29341740

ABSTRACT

We propose the digital quantum simulation of a minimal AdS/CFT model in controllable quantum platforms. We consider the Sachdev-Ye-Kitaev model describing interacting Majorana fermions with randomly distributed all-to-all couplings, encoding nonlocal fermionic operators onto qubits to efficiently implement their dynamics via digital techniques. Moreover, we also give a method for probing nonequilibrium dynamics and the scrambling of information. Finally, our approach serves as a protocol for reproducing a simplified low-dimensional model of quantum gravity in advanced quantum platforms as trapped ions and superconducting circuits.

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