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1.
J Environ Manage ; 312: 114931, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35338987

RESUMO

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.


Assuntos
Açúcares , Purificação da Água , Carboidratos , Fermentação , Hidrólise , Vapor
2.
Phys Rev Lett ; 118(3): 033202, 2017 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-28157370

RESUMO

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.

3.
Biochim Biophys Acta Gen Subj ; 1861(7): 1737-1749, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28315770

RESUMO

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.


Assuntos
Ciclodextrinas/química , DNA/química , Coroa de Proteína/química , Transfecção/métodos , Biofísica , Células HeLa , Humanos , Células MCF-7 , Nanopartículas
4.
Phys Rev Lett ; 117(9): 093902, 2016 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-27610855

RESUMO

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.

5.
Phys Rev Lett ; 117(27): 276806, 2016 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-28084773

RESUMO

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.

6.
Opt Express ; 22(24): 29778-86, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25606907

RESUMO

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.


Assuntos
Lasers , Modelos Teóricos , Simulação por Computador , Dinâmica não Linear , Análise Numérica Assistida por Computador , Análise Espectral
7.
Artigo em Inglês | MEDLINE | ID: mdl-38428677

RESUMO

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.

8.
Phys Chem Chem Phys ; 15(23): 9384-91, 2013 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-23660801

RESUMO

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.

9.
Parasite ; 18(1): 85-7, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21395210

RESUMO

Trichinellosis is one of the most serious foodborne parasitic zoonoses in Europe. Wild carnivorous and omnivorous hosts are the main reservoirs of Trichinella spp. nematodes in nature. In the winter of 2008-2009, an atypical clinical case of trichinellosis occurred for the consumption of pork from a wild boar (Sus scrofa) hunted in southwestern Alps in Italy. The symptomatic individual showed delayed development of oedemas in the lower limbs and eosinophilia, which appeared three months after infection. Muscle samples harboured 3.8 larvae/g, which were identified as Trichinella britovi. During the epidemiological investigation, anti-Trichinella IgG were detected in five hunters.


Assuntos
Carne/parasitologia , Doenças dos Suínos/parasitologia , Triquinelose/etiologia , Zoonoses , Animais , Feminino , Humanos , Itália/epidemiologia , Larva , Extremidade Inferior , Pessoa de Meia-Idade , Músculos/parasitologia , Prevalência , Sus scrofa , Suínos , Doenças dos Suínos/transmissão , Trichinella/isolamento & purificação , Triquinelose/epidemiologia , Zoonoses/epidemiologia , Zoonoses/parasitologia , Zoonoses/transmissão
10.
Opt Lett ; 35(9): 1350-2, 2010 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-20436565

RESUMO

We investigated theoretically and experimentally the ultrafast birefringence induced by impulsive alignment in a molecular gas during optical filamentation. This phenomenon is able to substantially affect the polarization state of an ultrashort laser pulse that propagates through the aligned medium at suitable delays from a first aligning pulse. We exploited this modulation of the polarization state in order to effectively control the high-order harmonic generation (HHG) process, which is strongly dependent on the driving pulse polarization. These results open new and fascinating perspectives for the tailoring of strong-field phenomena by means of polarization pulse shaping.

11.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4349-4352, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018958

RESUMO

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.


Assuntos
Sistema Nervoso Autônomo , Fotopletismografia , Algoritmos , Volume Sanguíneo , Frequência Cardíaca , Humanos , Adulto Jovem
12.
Opt Lett ; 34(20): 3125-7, 2009 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-19838247

RESUMO

A temporal gating on the high-order harmonic emission process is achieved using an intense 20 fs, 1.45 microm pulse (IR) in combination with an intense 13 fs, 800 nm pulse [visible (VIS)]. Exploiting this two-color gating scheme, a coherent continuous emission extending up to 160 eV using Ar gas and 200 eV using Ne gas is efficiently generated. The IR pulse contributes to significantly extending the harmonic emission to higher photon energies, whereas the VIS pulse improves the conversion efficiency of the process. These results indicate the possibility to produce bright attosecond pulses approaching the soft X spectral region.

13.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 6822-6825, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31947407

RESUMO

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.


Assuntos
Fotopletismografia , Algoritmos , Artefatos , Frequência Cardíaca , Processamento de Sinais Assistido por Computador
14.
J Nutr Health Aging ; 23(5): 414-424, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31021358

RESUMO

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.


Assuntos
Aminoácidos Essenciais/metabolismo , Suplementos Nutricionais/análise , Fadiga/fisiopatologia , Força Muscular/efeitos dos fármacos , Vitamina D/uso terapêutico , Vitaminas/uso terapêutico , Idoso , Método Duplo-Cego , Feminino , Voluntários Saudáveis , Humanos , Masculino , Fatores de Tempo , Vitamina D/farmacologia , Vitaminas/farmacologia
15.
J Sports Med Phys Fitness ; 48(3): 347-51, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18974721

RESUMO

Since the 1980's there has been high interest in branched-chain amino acids (BCAA) by sports nutrition scientists. The metabolism of BCAA is involved in some specific biochemical muscle processes and many studies have been carried out to understand whether sports performance can be enhanced by a BCAA supplementation. However, many of these researches have failed to confirm this hypothesis. Thus, in recent years investigators have changed their research target and focused on the effects of BCAA on the muscle protein matrix and the immune system. Data show that BCAA supplementation before and after exercise has beneficial effects for decreasing exercise-induced muscle damage and promoting muscle-protein synthesis. Muscle damage develops delayed onset muscle soreness: a syndrome that occurs 24-48 h after intensive physical activity that can inhibit athletic performance. Other recent works indicate that BCAA supplementation recovers peripheral blood mononuclear cell proliferation in response to mitogens after a long distance intense exercise, as well as plasma glutamine concentration. The BCAA also modifies the pattern of exercise-related cytokine production, leading to a diversion of the lymphocyte immune response towards a Th1 type. According to these findings, it is possible to consider the BCAA as a useful supplement for muscle recovery and immune regulation for sports events.


Assuntos
Aminoácidos de Cadeia Ramificada/uso terapêutico , Suplementos Nutricionais , Tolerância ao Exercício/fisiologia , Sistema Imunitário/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Aminoácidos de Cadeia Ramificada/química , Desempenho Atlético , Humanos , Inflamação , Fadiga Muscular/efeitos dos fármacos , Fadiga Muscular/fisiologia , Músculo Esquelético/fisiologia , Avaliação Nutricional , Estado Nutricional
16.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1515142

RESUMO

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.

17.
J Food Prot ; 69(9): 2289-92, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16995540

RESUMO

To protect public health from bovine spongiform encephalopathy, European Commission Regulation EC 1139/2003 on monitoring programs and specified risk material requires that as of 1 October 2003, each member state has in place a sampling plan with an appropriate laboratory test to detect central nervous system (CNS) tissue in bovine head meat harvested at slaughterhouses or cutting plants. With this study, we wanted to evaluate the accuracy and reliability of an enzyme immunoassay, the RIDASCREEN Risk Material 10/5, in targeting a CNS-specific marker, the glial fibrillary acidic protein. A receiver operating characteristics curve was plotted to identify the best cutoff of CNS concentration. Reliability was calculated by Cohen's kappa on data from two diagnostic sessions. Test performance showed high sensitivity and specificity (97.9 and 97.4%, respectively) for a cutoff value between positive and negative at a CNS concentration of 0.049%; reliability of test precision was also very good. When these criteria are applied, the RIDASCREEN Risk Material 10/5 test appears to be a reliable tool for monitoring CNS tissue contamination in meat. This diagnostic procedure should therefore be recommended for national application in monitoring programs.


Assuntos
Matadouros , Contaminação de Alimentos/análise , Proteína Glial Fibrilar Ácida/análise , Técnicas Imunoenzimáticas/métodos , Animais , Biomarcadores/análise , Bovinos , Qualidade de Produtos para o Consumidor , Encefalopatia Espongiforme Bovina/imunologia , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
Chem Commun (Camb) ; 52(66): 10117-20, 2016 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-27387975

RESUMO

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.


Assuntos
Química Click/métodos , DNA/química , Nanopartículas/química , Oligossacarídeos/química , Trealose/química , Animais , Células COS , Chlorocebus aethiops , DNA/metabolismo , Concentração de Íons de Hidrogênio , Nanopartículas/metabolismo , Oligossacarídeos/metabolismo , Espalhamento a Baixo Ângulo , Trealose/metabolismo , Difração de Raios X
19.
Appl Biochem Biotechnol ; 121-124: 887-99, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15930568

RESUMO

The application of Fenton's reaction to enhance the fermentability of prehydrolysates obtained from steam explosion pretreatment of poplar biomass was studied. Reaction conditions of temperature and H2O2 and Fe(II) concentrations were studied. The fermentability of prehydrolysate treated by Fenton's reaction was tested by using different inoculum sizes of thermotolerant strain Kluyveromyces marxianus CECT 10875. The highest percentages of toxic compound degradation (ranging from 71 to 93% removal) were obtained at the highest H2O2 concentration tested (50 mM). However, a negative effect on fermentability was observed at this H2O2 concentration at the lower inoculum loading. An increase in inoculum size to 0.6 g/L resulted in an enhanced ethanol fermentation yield of 95% relative to control.


Assuntos
Etanol/metabolismo , Peróxido de Hidrogênio/química , Ferro/química , Kluyveromyces/metabolismo , Modelos Biológicos , Populus/química , Populus/microbiologia , Vapor , Biomassa , Técnicas de Cultura de Células/métodos , Celulose/química , Celulose/metabolismo , Simulação por Computador , Hidrólise , Kluyveromyces/crescimento & desenvolvimento , Temperatura
20.
Astrophys J ; 807(2)2015 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-34646041

RESUMO

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.

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