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1.
Article in English | MEDLINE | ID: mdl-38428677

ABSTRACT

Pulmonary artery banding (PAB) is a procedure mainly performed during the neonatal period as an initial stage to definitive palliative reconstruction, a scenario in which the criteria for banding adjustment are well defined. However, the indication for BAP in the adult is extraordinarily rare, even more in patients with single ventricle and unrepaired transposition of the great arteries (TGA), and there are no established criteria for banding adjustment. Due to the small number of these procedures, there is limited experience in their anesthetic management and complications. We describe a case of a 29-year-old patient diagnosed with a cyanotic congenital heart disease of double-inlet left ventricle with TGA and unrepaired mitral stenosis, who underwent to a hybrid procedure of PAB and enlargement of the communication between the two atria.

2.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1515142

ABSTRACT

Introducción: La apoplejía hipofisaria es un síndrome que se produce como consecuencia de una lesión isquémica o hemorrágica en la glándula pituitaria dando lugar a un déficit de hormonas hipofisarias. Se manifiesta en forma de deterioro neurológico con cefalea en trueno como síntoma prínceps, siendo la irritación meníngea una manifestación infrecuente. Métodos: Presentamos el caso de una mujer de 53 años con antecedente de madroadenoma productor de prolactina que comienza con cefalea, náuseas y deterioro de nivel de consciencia. Se detecta un hipopituitarismo incompleto con nivel de cortisol normal. El líquido cefalorraquídeo (LCR) es consistente con una pleocitosis aséptica sin respuesta a terapias antibióticas. Asocia paresia oculomotora y una RM craneal revela sangrado en el adenoma hipofisario con compromiso de seno cavernoso. Resultados: la sospecha inicial es una meningoencefalitis bacteriana por la fiebre, estupor y LCR con pleocitosis, si bien no se identifica microorganismo y no hay respuesta a antibióticos. El LCR de la apoplejía muestra una pleocitosis aséptica por irritación meníngea del espacio subaracnoideo por el sangrado y la necrosis de la glándula. El hipopituitarismo puede ser parcial o completo, siendo más frecuente el déficit selectivo. Especial atención merece el déficit de ACTH por la morbimortalidad que conlleva el fallo adrenal. La oftalmoparesia traduce implicación de seno cavernoso por incremento en la presión selar. Conclusiones: Destacamos la importancia de tener una sospecha diagnóstica de apoplejía ante un cuadro neurológico agudo para dirigir las investigaciones pertinentes con determinación hormonal y así iniciar una terapia sustitutiva temprana y una actitud neuroquirúrgica en caso de ser necesaria; precisando un manejo multidisciplinar.


Introduction: Pituitary apoplexy is a syndrome that occurs as a result of an ischemic or hemorrhagic lesion in the pituitary gland, leading to a deficiency of pituitary hormones. It manifests in the form of neurological deterioration with thunderclap headache as the main symptom, with meningeal irritation being an infrequent manifestation. Methods: We present the case of a 53-year-old woman with a history of prolactin-producing madroadenoma that began with headache, nausea and impaired level of consciousness. Incomplete hypopituitarism with normal cortisol level is detected. Cerebrospinal fluid (CSF) is consistent with an aseptic pleocytosis unresponsive to antibiotic therapy. It is associated with oculomotor paresis and a cranial MRI reveals bleeding in the pituitary adenoma with involvement of the cavernous sinus. Results: the initial suspicion is bacterial meningoencephalitis due to fever, stupor and CSF with pleocytosis, although no microorganism is identified and there is no response to antibiotics. CSF from stroke shows aseptic pleocytosis due to meningeal irritation of the subarachnoid space from bleeding and necrosis of the gland. Hypopituitarism can be partial or complete, selective deficiency being more frequent. ACTH deficiency deserves special attention due to the morbidity and mortality that adrenal failure entails. Ophthalmoparesis translates involvement of the cavernous sinus due to an increase in sellar pressure. Conclusions: We emphasize the importance of having a suspected diagnosis of apoplexy in case of an acute neurological condition, to direct the pertinent investigations with hormonal determination and thus initiate early replacement therapy and a neurosurgical approach if necessary; requiring a multidisciplinary management.

3.
Cir. Esp. (Ed. impr.) ; 100(6): 352-358, jun. 2022. ilus, tab, graf
Article in Spanish | IBECS | ID: ibc-207442

ABSTRACT

Introducción La pandemia producida por COVID-19 ocasionó la cancelación de los procedimientos quirúrgicos no esenciales en marzo de 2020. Con el reinicio de la actividad quirúrgica, los pacientes que se sometían a una cirugía fueron uno de los primeros grupos poblacionales a los que se realizó test PCR de forma sistemática. El objetivo de este estudio fue determinar la prevalencia de portadores asintomáticos de SARS-CoV-2 tras el reinicio de la actividad quirúrgica no esencial. Métodos Estudio observacional multicéntrico retrospectivo de los pacientes programados para cirugía o que se sometieron a cirugía urgente en Cataluña entre el 20 de abril y el 31 de mayo de 2020. Se revisaron los resultados microbiológicos de los test PCR preoperatorios, las historias clínicas y se realizó una encuesta epidemiológica a los pacientes con PCR positiva para SARS-CoV-2. Resultados Un total de 10.838 pacientes programados para una intervención quirúrgica o a los que se realizó una cirugía urgente fueron sometidos a cribado para COVID-19. Ciento dieciocho pacientes (1,09%) fueron positivos para SARS-CoV-2 en las 72h previas a la cirugía. La prevalencia de portadores asintomáticos fue del 0,7% (IC95%: 0,6-0,9%). La primera semana del estudio presentó la prevalencia más alta de portadores asintomáticos [1,9% (IC95%: 1,1-3,2%)]. Conclusiones Los bajos niveles de portadores asintomáticos de infección por COVID-19 obtenidos en la población quirúrgica de los hospitales de Cataluña tras el reinicio de la actividad quirúrgica muestran que la mayoría de pacientes se pudieron someter a procedimientos quirúrgicos sin los riesgos de las complicaciones asociadas al COVID-19 en el periodo perioperatorio (AU)


Introduction The COVID-19 pandemic led to the cancellation of non-essential surgical procedures in March 2020. With the resumption of surgical activity, patients undergoing surgery were one of the first population groups to be systematically tested for PCR. The aim of this study was to determine the prevalence of asymptomatic SARS-CoV-2 carriers after the resumption of non-essential surgical activity. Methods Retrospective multicenter observational study of patients scheduled for surgery or undergoing emergency surgery in Catalonia between 20 April and 31 May 2020. The microbiological results of preoperative PCR tests and clinical records were reviewed, and an epidemiological survey was conducted on patients with positive PCR for SARS-CoV-2. Results A total of 10,838 patients scheduled for surgery or who underwent emergency surgery were screened for COVID-19. One hundred and eighteen patients (1.09%) were positive for SARS-CoV-2 in the 72hours prior to surgery. The prevalence of asymptomatic carriers was 0.7% (95%CI: 0.6% - 0.9%). The first week of the study presented the highest prevalence of asymptomatic carriers [1.9% (95%CI: 1.1%-3.2%)]. Conclusions The low levels of asymptomatic carriers of COVID-19 infection obtained in the surgical population of hospitals in Catalonia after the resumption of surgical activity, shows that most patients were able to undergo surgical procedures without the risks of COVID-19 associated complications in the perioperative period (AU)


Subject(s)
Humans , Male , Female , Middle Aged , Aged , Coronavirus Infections/diagnosis , Coronavirus Infections/epidemiology , Pneumonia, Viral/diagnosis , Pneumonia, Viral/epidemiology , Elective Surgical Procedures , Emergency Service, Hospital , Retrospective Studies , Asymptomatic Infections , Spain/epidemiology , Prevalence
4.
J Environ Manage ; 312: 114931, 2022 Jun 15.
Article in English | MEDLINE | ID: mdl-35338987

ABSTRACT

The widespread use of wipes and other sanitary products made of nonwoven fibres has led to an enormous problem in wastewater treatment systems that has been underestimated for some time. To date, there are no practical alternatives for recycling and valorisation. In this study, cellulosic rejections recovered from a wastewater treatment plant in Barcelona (Spain) were characterised and treated using hydrothermal and enzymatic methods to obtain free sugars. Steam explosion and autoclave pre-treatments were performed at different temperatures (120, 130, or 150 °C) and residence times (10-40 min) under neutral, acidic or basic conditions. The solids obtained after the pre-treatment, as well as the untreated material, were subjected to enzymatic hydrolysis using commercial enzymes. The untreated substrate reached the highest sugar production: 29 g glucose and xylose per 100 g of the cellulosic rejections, equivalent to 86% of the sugars contained in the initial material. These sugars can subsequently be transformed into biofuels or bioproducts within a biorefinery approach.


Subject(s)
Sugars , Water Purification , Carbohydrates , Fermentation , Hydrolysis , Steam
5.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4349-4352, 2020 07.
Article in English | MEDLINE | ID: mdl-33018958

ABSTRACT

Video Photoplethysmography (vPPG) allows for estimation of blood volume pulse (BVP) from the skin by means of a video camera recording at high frequency rate. The estimation procedure presents several drawbacks in its application to real world conditions, such as light changes or movements that often generate artifacts in the extracted BVP waveform. In addition, the process requires a skin segmentation algorithm to distinguish skin pixels from the background. To date, even the most refined skin segmentation algorithms still need a manual definition that could lead to incorrect pixel classification, and consequently to a decrease in the signal-to-noise ratio (SNR). We here propose a fully autonomic procedure able to extract BVP from video recordings of the skin in real world conditions.The experimental protocol is designed to record the signals of interest and to evaluate changes in the Autonomic Nervous System modulation of the heart during a baseline condition and a controlled breathing phase. Video recordings are gathered from 4 young healthy subjects (age: 21±1 years). vPPG signals are processed in order to extract the BVP waveform, and a peak detection algorithm detects pulse wave peaks that are then used to compute specific measures of heart rate variability (HRV).The procedure is successfully validated by comparing the extracted HRV measures against those extracted using a finger photoplethysmograph (fPPG) using three different skin segmentation algorithms from BVP signals.


Subject(s)
Autonomic Nervous System , Photoplethysmography , Algorithms , Blood Volume , Heart Rate , Humans , Young Adult
6.
J Nutr Health Aging ; 23(5): 414-424, 2019.
Article in English | MEDLINE | ID: mdl-31021358

ABSTRACT

OBJECTIVE: To counteract muscle mass, muscle strength and power loss during aging, and to study age-related change of neuromuscular manifestation of fatigue in relation to nutritional supplementation. DESIGN: randomized controlled double-blind study. SETTING: Twice-daily consumption for 12 weeks of an Essential Amino Acids (EAA)-based multi-ingredient nutritional supplement containing EAA, creatine, vitamin D and Muscle Restore Complex®. PARTICIPANTS: 38 healthy elderly subjects (8 male, 30 female; age: 68.91±4.60 years; body weight: 69.40±15.58 kg; height: 1.60±0.09 m) were randomized and allocated in supplement (SUPP) or placebo (PLA) group. Mean Measurements: Vitamin D blood level; Appendicular Lean Mass (ALM); Visceral Adipose Tissue (VAT); Maximal Voluntary Contraction (MVC) and Peak Power (PP); myoelectric descriptors of fatigue: Fractal Dimension and Conduction Velocity initial values (FD iv, CV iv), their rates of change (FD slopes, CV slopes) and the Time to perform the Task (TtT). Mean Results: Significant changes were found in SUPP compared to baseline: Vitamin D (+8.73 ng/ml; p<0.001); ALM (+0.34 kg; p<0.001); VAT (-76.25 g; p<0.001); MVC (+0.52 kg; p<0.001); PP (+4.82 W; p<0.001). Between group analysis (SUPP Vs. PLA) showed improvements: vitamin D blood levels (+11,72 ng/ml; p<0.001); Legs FFM (+443.7 g; p<0.05); ALM (+0.53 kg; p<0.05); MVC (+1.38 kg; p<0.05); PP (+9.87 W; p<0.05). No statistical changes were found for FD iv, CV iv, FD and CV slopes and TtT, either compared to baseline or between groups. Significant correlations between mean differences in SUPP group were also found. CONCLUSION: The study demonstrates that in healthy elderly subjects an EAA-based multi-ingredient nutritional supplementation of 12 weeks is not effective to change myoelectric manifestation of fatigue and TtT failure but can positively affect muscle mass, muscle strength, muscle power and VAT, counterbalancing more than one year of age-related loss of muscle mass and strength.


Subject(s)
Amino Acids, Essential/metabolism , Dietary Supplements/analysis , Fatigue/physiopathology , Muscle Strength/drug effects , Vitamin D/therapeutic use , Vitamins/therapeutic use , Aged , Double-Blind Method , Female , Healthy Volunteers , Humans , Male , Time Factors , Vitamin D/pharmacology , Vitamins/pharmacology
7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 6822-6825, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31947407

ABSTRACT

In recent years, there has been a growing interest in video Photoplethysmography (vPPG), a technique able to estimate cardiovascular parameters from video recordings of the skin. Despite the growing interest in vPPG technology, there are still problems in extracting the correct waveform of blood volume pulse, mainly due to real world artifacts, such as changes in light condition and movement artifacts. Another important issue is the correct definition of skin against background. Therefore, we propose an algorithm of skin detection that is able to recognize skin pixels solid to variations of luminosity. We recorded the signals of interest during an experimental protocol designed to provide thermal stimulation and observe the resulting Autonomic Nervous System changes. Experimental data were gathered from 10 young healthy subjects (age: 21±2 years). Video recordings are processed using a band-pass filter and then an automatic algorithm of peak detection is applied to detect the pulse wave peaks, then used to estimate heart rate variability (HRV). The efficiency and stability of the algorithm are compared against finger-PPG waveforms. Preliminary results show an overall statistical agreement between time and frequency domain indexes. However, further efforts are required to improve the estimation of frequency components, particularly during rest.


Subject(s)
Photoplethysmography , Algorithms , Artifacts , Heart Rate , Signal Processing, Computer-Assisted
8.
Prog. obstet. ginecol. (Ed. impr.) ; 60(3): 236-239, mayo-jun. 2017. ilus
Article in Spanish | IBECS | ID: ibc-164068

ABSTRACT

Los defectos de la pared abdominal engloban un amplio grupo de patologías que pueden clasificarse en distintos tipos según sus características anatomopatológicas y patogenia. El complejo OEIS complex es una rara entidad compuesta por onfalocele, extrofia vesical, ano imperforado y defectos espinales, dando origen a las siglas en inglés (Omphalocele, bladder Exstrophy, Imperforateanu and Spinal defects) y asociándose también a ausencia de genitales externos, deformidad en la flexión de miembros, defectos en pie y arteria umbilical única. Su incidencia estimada es de 1/200.000 a 1/400.000 nacidos en gestaciones únicas, menor en gestaciones gemelares. Su etiología en la mayoría de las ocasiones es desconocida, esporádica y heterogénea, pudiendo asociarse a varios factores. Presentamos el caso de una mujer con gestación monocorial monoamniótica y afectación de uno de los gemelos por este defecto (complejo OEIS complex), presentando un segundo gemelo totalmente sano, lo que demuestra la falta de conocimiento en cuanto a la etiología de esta rara entidad y la improbable implicación de los factores genéticos (AU)


The abdominal wall defects encompass a variety of disorders that can be classified into different types according to their pathologic features and pathogenesis. The OEIS complex is a rare complex composed of omphalocele, bladder exstrophy , imperforate anus and spinal defects, giving rise to the acronym (Omphalocele, bladder Exstrophy, Imperforate anus and Spinal defects) and associating with the absence of external genitalia, flexion deformity member, standing defects, and single umbilical artery. Its incidence is estimated from 1/400,000 to 1/200,000 born in singleton pregnancies, lower in twin pregnancies. The etiology in most cases is unknown, sporadic and heterogeneous it may be associated with several factors. We report the case of a woman with monochorionic monoamniotic gestation and involvement of one of the twins for this defect (OEIS complex complex), presenting one second fully healthy twin, demonstrating the lack of knowledge regarding the etiology of this rare entity and the unlikely involvement of genetic factors (AU)


Subject(s)
Female , Pregnancy , Humans , Abdominal Wall/abnormalities , Abdominal Wall , Pregnancy, Twin , Fetus/abnormalities , Ultrasonography, Prenatal , Hernia, Umbilical/complications , Hernia, Umbilical , Bladder Exstrophy/complications , Bladder Exstrophy , Anus, Imperforate/complications , Spinal Canal/abnormalities , Prenatal Diagnosis/methods
9.
Biochim Biophys Acta Gen Subj ; 1861(7): 1737-1749, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28315770

ABSTRACT

The self-assembling processes underlining the capabilities of facially differentiated ("Janus") polycationic amphiphilic cyclodextrins (paCDs) as non-viral gene nanocarriers have been investigated by a pluridisciplinary approach. Three representative Janus paCDs bearing a common tetradecahexanoyl multitail domain at the secondary face and differing in the topology of the cluster of amino groups at the primary side were selected for this study. All of them compact pEGFP-C3 plasmid DNA and promote transfection in HeLa and MCF-7 cells, both in absence and in presence of human serum. The electrochemical and structural characteristics of the paCD-pDNA complexes (CDplexes) have been studied by using zeta potential, DLS, SAXS, and cryo-TEM. paCDs and pDNA, when assembled in CDplexes, render effective charges that are lower than the nominal ones. The CDplexes show a self-assembling pattern corresponding to multilamellar lyotropic liquid crystal phases, characterized by a lamellar stacking of bilayers of the CD-based vectors with anionic pDNA sandwiched among them. When exposed to human serum, either in the absence or in the presence of pDNA, the surface of the cationic CD-based vector becomes coated by a protein corona (PC) whose composition has been analyzed by nanoLC-MS/MS. Some of the CDplexes herein studied showed moderate-to-high transfection levels in HeLa and MCF-7 cancer cells combined with moderate-to-high cell viabilities, as determined by FACS and MTT reduction assays. The ensemble of data provides a detail picture of the paCD-pDNA-PC association processes and a rational base to exploit the protein corona for targeted gene delivery on future in vivo applications.


Subject(s)
Cyclodextrins/chemistry , DNA/chemistry , Protein Corona/chemistry , Transfection/methods , Biophysics , HeLa Cells , Humans , MCF-7 Cells , Nanoparticles
10.
Phys Rev Lett ; 118(3): 033202, 2017 Jan 20.
Article in English | MEDLINE | ID: mdl-28157370

ABSTRACT

The hitherto unexplored two-photon doubly excited states [Ne^{*}(2p^{-1}3s)]_{2} were experimentally identified using the seeded, fully coherent, intense extreme ultraviolet free-electron laser FERMI. These states undergo ultrafast interatomic Coulombic decay (ICD), which predominantly produces singly ionized dimers. In order to obtain the rate of ICD, the resulting yield of Ne_{2}^{+} ions was recorded as a function of delay between the extreme ultraviolet pump and UV probe laser pulses. The extracted lifetimes of the long-lived doubly excited states, 390(-130/+450) fs, and of the short-lived ones, less than 150 fs, are in good agreement with ab initio quantum mechanical calculations.

11.
Phys Rev Lett ; 117(9): 093902, 2016 Aug 26.
Article in English | MEDLINE | ID: mdl-27610855

ABSTRACT

We investigated the giant resonance in xenon by high-order harmonic generation spectroscopy driven by a two-color field. The addition of a nonperturbative second harmonic component parallel to the driving field breaks the symmetry between neighboring subcycles resulting in the appearance of spectral caustics at two distinct cutoff energies. By controlling the phase delay between the two color components it is possible to tailor the harmonic emission in order to amplify and isolate the spectral feature of interest. In this Letter we demonstrate how this control scheme can be used to investigate the role of electron correlations that give birth to the giant resonance in xenon. The collective excitations of the giant dipole resonance in xenon combined with the spectral manipulation associated with the two-color driving field allow us to see features that are normally not accessible and to obtain a good agreement between the experimental results and the theoretical predictions.

12.
Chem Commun (Camb) ; 52(66): 10117-20, 2016 Aug 09.
Article in English | MEDLINE | ID: mdl-27387975

ABSTRACT

The convergent preparation of Janus molecular nanoparticles by thiourea-"clicking" of α,α'-trehalose halves has been implemented; the strategy allows access to macrocyclic derivatives with seggregated cationic and lipophilic domains that in the presence of DNA undergo pH-dependent self-assembly into lamellar superstructures, as established by electrochemical, structural (SAXS), microscopical (TEM) and computational techniques, that mediate transfection in vitro and in vivo.


Subject(s)
Click Chemistry/methods , DNA/chemistry , Nanoparticles/chemistry , Oligosaccharides/chemistry , Trehalose/chemistry , Animals , COS Cells , Chlorocebus aethiops , DNA/metabolism , Hydrogen-Ion Concentration , Nanoparticles/metabolism , Oligosaccharides/metabolism , Scattering, Small Angle , Trehalose/metabolism , X-Ray Diffraction
13.
Phys Rev Lett ; 117(27): 276806, 2016 Dec 30.
Article in English | MEDLINE | ID: mdl-28084773

ABSTRACT

Ne clusters (∼5000 atoms) were resonantly excited (2p→3s) by intense free electron laser (FEL) radiation at FERMI. Such multiply excited clusters can decay nonradiatively via energy exchange between at least two neighboring excited atoms. Benefiting from the precise tunability and narrow bandwidth of seeded FEL radiation, specific sites of the Ne clusters were probed. We found that the relaxation of cluster surface atoms proceeds via a sequence of interatomic or intermolecular Coulombic decay (ICD) processes while ICD of bulk atoms is additionally affected by the surrounding excited medium via inelastic electron scattering. For both cases, cluster excitations relax to atomic states prior to ICD, showing that this kind of ICD is rather slow (picosecond range). Controlling the average number of excitations per cluster via the FEL intensity allows a coarse tuning of the ICD rate.

14.
Astrophys J ; 807(2)2015 Jul 10.
Article in English | MEDLINE | ID: mdl-34646041

ABSTRACT

It is widely accepted that cosmic rays (CRs) up to at least PeV energies are Galactic in origin. Accelerated particles are injected into the interstellar medium where they propagate to the farthest reaches of the Milky Way, including a surrounding halo. The composition of CRs coming to the solar system can be measured directly and has been used to infer the details of CR propagation that are extrapolated to the whole Galaxy. In contrast, indirect methods, such as observations of γ-ray emission from CR interactions with interstellar gas, have been employed to directly probe the CR densities in distant locations throughout the Galactic plane. In this article we use 73 months of data from the Fermi Large Area Telescope in the energy range between 300 MeV and 10 GeV to search for γ-ray emission produced by CR interactions in several high- and intermediate-velocity clouds (IVCs) located at up to ~7 kpc above the Galactic plane. We achieve the first detection of IVCs in γ rays and set upper limits on the emission from the remaining targets, thereby tracing the distribution of CR nuclei in the halo for the first time. We find that the γ-ray emissivity per H atom decreases with increasing distance from the plane at 97.5% confidence level. This corroborates the notion that CRs at the relevant energies originate in the Galactic disk. The emissivity of the upper intermediate-velocity Arch hints at a 50% decline of CR densities within 2 kpc from the plane. We compare our results to predictions of CR propagation models.

15.
Faraday Discuss ; 171: 133-43, 2014.
Article in English | MEDLINE | ID: mdl-25415258

ABSTRACT

High-order harmonic generation is a powerful and sensitive tool for probing atomic and molecular structures, combining in the same measurement an unprecedented attosecond temporal resolution with a high spatial resolution of the order of an angstrom. Imaging of the outermost molecular orbital by high-order harmonic generation has been limited for a long time to very simple molecules, like nitrogen. Recently we demonstrated a technique that overcame several of the issues that have prevented the extension of molecular orbital tomography to more complex species, showing that molecular imaging can be applied to a triatomic molecule like carbon dioxide. Here we report on the application of such a technique to nitrous oxide (N(2)O) and acetylene (C(2)H(2)). This result represents a first step towards the imaging of fragile compounds, a category which includes most of the fundamental biological molecules.

16.
Bioresour Technol ; 159: 421-32, 2014 May.
Article in English | MEDLINE | ID: mdl-24713236

ABSTRACT

With currently more than nine million hectares, olive tree cultivation has spread worldwide, table olives and olive oil as the main products. Moreover, a number of by-products and residues derived from both tree cultivation and the process of industrial olive oil production, most having no practical applications, are obtained yearly. This paper reviews the research regarding these by-products, namely biomass from olive tree pruning, olive stones, olive pomace and wastewaters obtained from the process of olive oil production. Furthermore, a wide range of compounds has been identified and can be produced using a broad definition of the term biorefinery based on olive tree biomass. As an example, this paper reviews ethanol production as one of the main proposed applications, as well as research on other value-added products. Finally, this paper also assesses recent technological advances, future perspectives and challenges in each stage of the process.


Subject(s)
Biomass , Biotechnology/methods , Olea/chemistry , Plant Leaves/chemistry , Trees/chemistry , Wastewater/chemistry
17.
Bioresour Technol ; 158: 262-8, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24607463

ABSTRACT

A pretreatment that combines a thermo-mechanical process (extrusion) with chemical and biological catalysts to produce fermentable sugars from barley straw (BS) biomass was investigated. BS was firstly extruded with alkali and then, the pretreated material (extrudate) was submitted to extrusion with hydrolytic enzymes (bioextrusion). The bioextrudate was found to have 35% (w/w dwb) of total solids in soluble form, partly coming from carbohydrate hydrolysis during bioextrusion. About 48% of soluble solids dry weight is comprised by sugars, mostly glucose and xylose. Further enzymatic hydrolysis of bioextrudate could be successfully carried out at high solid loading level of 30% (w/v), with sugar production yield of 32 g glucose and 18 g xylose/100g bioextrudate at 72 h incubation (equivalent to 96 and 52 g/l concentration, respectively). These results, together with the high level of integration of the process, indicate a great potential of this pretreatment technology for sugar production from lignocellulosic substrates.


Subject(s)
Alkalies/chemistry , Biomass , Carbohydrates/biosynthesis , Enzymes/chemistry , Hordeum/metabolism
18.
Opt Express ; 22(24): 29778-86, 2014 Dec 01.
Article in English | MEDLINE | ID: mdl-25606907

ABSTRACT

High order harmonic generation (HHG) has shown its impact on several applications in Attosecond Science and Atomic and Molecular Physics. Owing to the complexity of the experimental setup for the generation and characterization of harmonics, as well as to the large computational costs of numerical modelling, HHG is generally performed and modelled in collinear geometry. Recently, several experiments have been performed exploiting non-collinear geometry, such as HHG in a grating of excited molecules created by crossing beams. In such studies, harmonics were observed at propagation directions different from those of the driving pulses; moreover the scattered harmonics were angularly dispersed.In this work we report on a new regime of HHG driven by multiple beams, where the harmonics are generated by three synchronized, intense laser pulses organized in a non-planar geometry. Although the configuration we explore is well within the strong-field regime, the scattered harmonics we observe are not angularly dispersed.


Subject(s)
Lasers , Models, Theoretical , Computer Simulation , Nonlinear Dynamics , Numerical Analysis, Computer-Assisted , Spectrum Analysis
19.
Bioresour Technol ; 153: 101-7, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24345569

ABSTRACT

In this work, the effect of phosphoric acid (1% w/w) in steam explosion pretreatment of water extracted olive tree pruning at 175°C and 195°C was evaluated. The objective is to produce ethanol from all sugars (mainly glucose and xylose) contained in the pretreated material. The water insoluble fraction obtained after pretreatment was used as substrate in a simultaneous saccharification and fermentation (SSF) process by a commercial strain of Saccharomyces cerevisiae. The liquid fraction, containing mainly xylose, was detoxified by alkali and ion-exchange resin and then fermented by the xylose fermenting yeast Scheffersomyces stipitis. Ethanol yields reached in a SSF process were close to 80% when using 15% (w/w) substrate consistency and about 70% of theoretical when using prehydrolysates detoxified by ion-exchange resins. Considering sugars recovery and ethanol yields about 160g of ethanol from kg of water extracted olive tree pruning could be obtained.


Subject(s)
Biotechnology/methods , Ethanol/metabolism , Glucose/metabolism , Olea/chemistry , Phosphoric Acids/pharmacology , Steam , Xylose/metabolism , Carbohydrate Metabolism/drug effects , Catalysis/drug effects , Fermentation/drug effects , Hydrolysis/drug effects , Lipase/metabolism , Microbial Viability/drug effects , Saccharomyces cerevisiae/drug effects , Saccharomyces cerevisiae/metabolism , Solubility , Time Factors , Trees/chemistry , Waste Products , beta-Glucosidase/metabolism
20.
Phys Chem Chem Phys ; 15(23): 9384-91, 2013 Jun 21.
Article in English | MEDLINE | ID: mdl-23660801

ABSTRACT

The dynamics of excited states in α,ω-dinaphthylpolyyne, a class of linear sp-carbon chains, has been investigated by ultrafast transient absorption spectroscopy and DFT//TDDFT calculations. We show that the role of molecular conformers, in which end-capped naphthalene rings are planar or perpendicular to the polyyne plane, is fundamental for understanding both the steady state properties, such as UV-Vis absorption spectra and vibronic transitions, and the ultrafast transient absorption features. In particular, we observed in one of the conformers the ultrafast formation of a narrow photo-induced absorption band rising within 30 ps. This band can be assigned to an inter-system crossing event leading to the formation of triplet excited states.

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