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Convergence among treatment, prevention, and developmental psychosocial intervention approaches has led to the recognition of the need for evaluation models and research designs that employ a full range of evaluation information to provide an empirical basis for enhancing the efficiency, efficacy, and effectiveness of prevention and psychosocial positive youth development interventions (PYD). This study reports an investigation of a PYD psychosocial program using an Outcome Mediation Cascade (OMC) evaluation model, which is an integrated model for evaluating the empirical intersection between intervention and developmental processes. The Changing Lives Program (CLP) is a community engaged PYD psychosocial intervention for multi-ethnic, multi-problem at risk youth in urban alternative high schools. Findings indicated that the hypothesized model fit the data, χ²(7) = 6.991, p = .43, RMSEA = .00, CFI = 1.00, WRMR = .459. Findings also provided preliminary evidence consistent with the hypothesis that, in addition to having effects on targeted positive outcomes, PYD interventions are likely to have progressive cascading effects on untargeted problem outcomes (in this case, behavioral outcomes) that operate through effects on positive outcomes. [ABSTRACT FROM AUTHOR]

Lignin ist ein reichlich vorhandenes Biopolymer mit hohem Kohlenstoffgehalt und hoher Aromatizität. Trotz seines Potenzials als Rohstoff für die Kraftstoffherstellung und die chemische Industrie ist Lignin noch immer das am wenigsten genutzte Biopolymer der Lignocellulose. Zur effektiven Aufwertung von Lignin ist eine sorgfältige Feinabstimmung mehrerer vorgeschalteter Prozessstufen (d. h. Biotechnik von Lignin, Abtrennung von Lignin und katalytische Umwandlung von Lignin in der Anfangsphase) und mehrerer nachgeschalteter Prozessstufen (d. h. Depolymerisation und Verwertung von Lignin) erforderlich, die den Einsatz und das Zusammenwirken eines breiten Spektrums wissenschaftlicher Disziplinen erfordert. Dieser Aufsatz liefert eine Analyse der neuesten Fortschritte bei der Verwertung von Lignin “vom Anfang bis zum Ende”. Besonderes Augenmerk liegt auf dem verbesserten Verständnis der Biosynthese und Struktur von Lignin, den Unterschieden in Struktur und chemischer Bindung zwischen nativen und technischen Ligninen, den neu aufkommenden Verfahren der katalytischen Verwertung und den Zusammenhängen zwischen Ligninstruktur und Katalysatorleistung. Den Wald vor lauter Bäumen sehen: Lignin ist ein reichlich vorhandenes Biopolymer mit hohem Kohlenstoffgehalt und hoher Aromatizität. Eine kritische Analyse der vor ‐ und nachgeschalteten Verfahrensschritte der Ligninverwertung wird gegeben, einschließlich Biotechnik, Bioraffination und Katalyse. [ABSTRACT FROM AUTHOR]

Lignin is an abundant biopolymer with a high carbon content and high aromaticity. Despite its potential as a raw material for the fuel and chemical industries, lignin remains the most poorly utilised of the lignocellulosic biopolymers. Effective valorisation of lignin requires careful fine-tuning of multiple "upstream" (i.e., lignin bioengineering, lignin isolation and "early-stage catalytic conversion of lignin") and "downstream" (i.e., lignin depolymerisation and upgrading) process stages, demanding input and understanding from a broad array of scientific disciplines. This review provides a "beginning-to-end" analysis of the recent advances reported in lignin valorisation. Particular emphasis is placed on the improved understanding of lignin's biosynthesis and structure, differences in structure and chemical bonding between native and technical lignins, emerging catalytic valorisation strategies, and the relationships between lignin structure and catalyst performance. [ABSTRACT FROM AUTHOR]

In this report, Ni/ZrO 2 , Ni/Al 2 O 3 , Ni/Al 2 O 3 -KF, Ni/SBA-15, and Ni/Al-SBA-15 were examined as catalysts for the hydrodeoxygenation of diphenyl ether. Adopting the degree of deoxygenation and yield of monocyclic products as the criteria for the catalyst selection, Ni/Al-SBA-15 was identified as the best catalyst for HDO of diphenyl ether. In fact, in the presence of Ni/Al-SBA-15, full conversion of the model compound into cyclohexane was achieved with high selectivity (98%). Most strikingly, Ni/Al-SBA-15 is capable of hydrodeoxygenating Organosolv lignin with selectivity to cycloalkanes higher than 99%. Owing to the similarities to hydrocarbons derived from petroleum, the lignin-derived alkanes could well be refined into drop-in fuels by conventional oil refinery processes. Moreover, in a broader perspective, the current results also highlight the importance of Al-SBA-15, as an acidic support alternative to zeolites or other acidic materials, for the HDO of phenolic streams. [ABSTRACT FROM AUTHOR]

Through catalytic hydrogen transfer reactions, a new biorefining method results in the isolation of depolymerized lignin-a non-pyrolytic lignin bio-oil-in addition to pulps that are amenable to enzymatic hydrolysis. Compared with organosolv lignin, the lignin bio-oil is highly susceptible to further hydrodeoxygenation under low-severity conditions and therefore establishes a unique platform for lignin valorization by heterogeneous catalysis. Overall, the potential of a catalytic biorefining method designed from the perspective of lignin utilization is reported. [ABSTRACT FROM AUTHOR]

Through catalytic hydrogen transfer reactions, a new biorefining method results in the isolation of depolymerized lignin-a non-pyrolytic lignin bio-oil-in addition to pulps that are amenable to enzymatic hydrolysis. Compared with organosolv lignin, the lignin bio-oil is highly susceptible to further hydrodeoxygenation under low-severity conditions and therefore establishes a unique platform for lignin valorization by heterogeneous catalysis. Overall, the potential of a catalytic biorefining method designed from the perspective of lignin utilization is reported. [ABSTRACT FROM AUTHOR]

The molecular understanding of the chemistry of 1,4-β-glucans is essential for designing new approaches to the conversion of cellulose into platform chemicals and biofuels. In this endeavor, much attention has been paid to the role of hydrogen bonding occurring in the cellulose structure. So far, however, there has been little discussion about the implications of the electronic nature of the 1,4-β-glycosidic bond and its chemical environment for the activation of 1,4-β-glucans toward acid-catalyzed hydrolysis. This report sheds light on these central issues and addresses their influence on the acid hydrolysis of cellobiose and, by analogy, cellulose. The electronic structure of cellobiose was explored by DFT at the BB1 K/6-31++G(d,p) level. Natural bond orbital (NBO) analysis was performed to grasp the key bonding concepts. Conformations, protonation sites, and hydrolysis mechanisms were examined. The results for cellobiose indicate that cellulose is protected against hydrolysis not only by its supramolecular structure, as currently accepted, but also by its electronic structure, in which the anomeric effect plays a key role. [ABSTRACT FROM AUTHOR]

Ausweg gefunden: Die Umwandlung von Lignin in niedrigsiedende Arene anstatt hochsiedender Phenole könnte eine enorme Vereinfachung konventioneller Raffinerieprozesse bedeuten. Ein neuer Prozess für die Depolymerisation von Lignin mit gleichzeitiger Umwandlung von Phenolen in Arene wird beschrieben. Die Methode bietet auch einen allgemeinen Zugang zur Veredelung von Bioölen zu Arenen unter milden Bedingungen. [ABSTRACT FROM AUTHOR]

Finding a workaround: The conversion of lignin into low‐boiling‐point arenes instead of high‐boiling‐point phenols could greatly facilitate conventional refinery processes. A new procedure for the depolymerization of lignin and simultaneous conversion phenols into arenes is described. The method can also be rendered as a fundamental finding for the upgrade of bio‐oils to arenes under mild conditions. [ABSTRACT FROM AUTHOR]

This study describes the development of a qualitative extension for the Personally Expressive Activities Questionnaire (PEAQ), a widely used quantitative questionnaire assessing feeling of personal expressiveness, a core positive identity construct. The PEAQ qualitative extension was developed as part of an ongoing effort to develop and refine an easy-to-use, standardized, reliable method designed for use in adding a free response qualitative component to a full range of fixed response quantitative measures. This article reports basic psychometric properties for the qualitative extension and preliminary evidence of construct validity. The availability of a ready-at-hand standardized method for including free response qualitative extensions of widely used measures with known reliability and validity in developmental research provides a means for detecting and rendering theoretically meaningful: (a) unique sample-specific free response linguistic content properties, (b) linguistic content properties undetected by fixed response measures, and (c) newly emergent linguistic content properties of core developmental research concepts and constructs in ways not possible using fixed response methods alone. [ABSTRACT FROM AUTHOR]

Abstract: Simple aluminum salts activate hydrogen peroxide towards α,β-unsaturated ketones, affording as major products α,β-epoxyketones. The pathway of this reaction involves the interaction between [Al(H2O)6]3+ and H2O2, through hydrogen bonds, in the second-coordination sphere. This interaction enhances the proton exchange between non-coordinated water and hydrogen peroxide, as detected by 1H NMR experiments. By this means, the hydroperoxide anion, formed as reactive intermediate in the proton exchange between H2O and H2O2, can be trapped by α,β-unsaturated ketones. Surprisingly, this pathway is not followed when diethylmaleate is used as substrate. In this case, the radical addition of THF to the C diethylmaleate takes place with high selectivity, affording 2-(THF)-derivatives with high yields. [Copyright &y& Elsevier]

Abstract: Well-defined nanoparticles obtained by modern wet chemical synthesis methods can be very useful building blocks for construction of model heterogeneous catalysts. Here we show the challenges involved in the construction of heterogeneous Ni catalysts from supports and colloidal nanoparticles. Surprisingly, “1+1” is not equal to “the best catalyst”, following this concept. The thought-provoking lack of catalytic activity of supported Ni NPs in the hydrogenation of cyclohexene and the low activity of these materials in the steam reforming of ethanol were analyzed in details by TEM, XPS, DRIFTS and CO adsorption experiments. The factors responsible for the low catalytic activity of Ni/SiO2 system were proposed. The removal of the ligands, used in the synthesis of the colloidal Ni nanoparticles, in the post-steps of catalyst preparation is cumbersome. In fact, low temperature treatments are not able to efficiently expose the Ni surface whereas high-temperature treatments lead to particle sintering. In this systematic study several aspects of catalyst preparation through impregnation of colloidal nanoparticles are addressed. [Copyright &y& Elsevier]

Abstract: Hydrophobic liquid membranes have a high technological potential in many fields of separation science. The dynamics of these systems is very complex and still not fully understood. In this work we studied the effect of the incorporation of cationic and anionic l-tryptophan at pH 1.8 and 10.0, respectively, in Aerosol-OT reverse micelles performing small angle X-ray scattering experiments. The use of a synchrotron radiation source allowed efficient in situ data acquisition. Several insights on l-tryptophan transport dynamics through hydrophobic membranes containing AOT could be obtained from these SAXS experiments, such as amino acid site localization and changes in the reverse micelle sizes. [Copyright &y& Elsevier]

Conclusions. Diagnostic work-up should include contrast-enhanced computed tomography (CT) and mandible orthopantogram. When a dental origin of deep neck infection is suspected, the intravenous antibiotic regimen has to be active against gram-positive bacteria, both aerobes and anaerobes. Surgical exploration and drainage may be mandatory at presentation, or in cases not responding to medical therapy within the first 24 h. Objectives. Deep neck infections are still associated with significant morbidity and mortality rates when complications occur. Despite worldwide improvement in dental care and oral hygiene, a significant prevalence of deep neck infections caused by dental infections has been described recently (>40%). Patients and methods. We analysed retrospectively 85 cases of deep neck infection with dental origin out of 206 consecutive cases of deep neck infection diagnosed in our institution between 2000 and 2006. Results. The most frequent dental source was a periapical infection of the first mandibular molar, followed by second and third molar, respectively. Submandibular space infection involvement was diagnosed in 73 of 85 patients (85.9%), masticatory space infection in 28 (32.9%); in 56 patients (65.9%) the infection involved more than one space. Twenty-four patients (28.2%) were treated only with intravenous antibiotic therapy; 61 patients (71.8%) required both medical and surgical procedures. [ABSTRACT FROM AUTHOR]

Abstract: This report addresses several questions regarding the deactivation of alumina in catalytic epoxidation using aqueous 70% H2O2. The structural, textural, morphological, and chemical changes of a polycrystalline alumina (γ-Al2O3 and boehmite) were studied in five consecutives reactions of 24 h. The chemical and physical processes involved in the transformations during alumina recycling are attributed mainly to the presence of water in the reaction mixture. Water plays a dual role in the catalytic system. On the one hand, water may cause deleterious changes of the structure of γ-Al2O3 and its textural properties. On the other hand, the presence of water shifts the adsorption equilibria of the organic molecules (acetic acid, diols, and oligomers), preserving the type Ia Al which are active for catalytic epoxidation. In this way, the water in the alumina/H2O2 catalytic system seems to be significant in prolonging the lifetime of the catalyst. [Copyright &y& Elsevier]

Abstract: The changes in the structural, morphological and acidity properties of nanocrystalline aluminas provoked by hydration under a controlled humidity atmosphere at room temperature were studied. Besides the physical and chemical adsorption of water on the surface, the hydration process causes the formation of aluminum oxy-hydroxide and trihydroxide (boehmite and bayerite). The recalcination of hydrated γ-Al2O3 cannot recuperate the initial acidic properties of the material. The populations of weak to moderate acid sites strongly decrease under recalcination of hydrated aluminas. On the other hand, the stronger acid site populations are not strongly affected by recalcination. [Copyright &y& Elsevier]

Abstract: This study answers several pending questions about alumina-catalyzed epoxidation with aqueous 70 wt% H2O2. To evaluate the effect of the water-to-aluminum tri-sec-butoxide molar ratio, this was systematically changed from 1 to 24. The xerogels were calcined at 450 °C and gave different γ-Al2O3''s with distinct textural and acidic properties. A combination of 27Al MAS NMR and TPD-NH3 results of calcined aluminas allowed us to assign the type Ia Alas the catalytic sites for epoxidation. The type Ib Alhave no function in catalytic epoxidation, because ethyl acetate poisons these sites. The strong acid sites of types IIa, IIb, and III Al are responsible for the undesired H2O2 decomposition and decreased oxidant selectivity. [Copyright &y& Elsevier]

Abstract: The aluminas obtained by calcination of nanocrystalline boehmite, prepared by the sol–gel method, in the range 200–1000 °C were characterized by powder X-ray diffraction, thermogravimetric analysis, Fourier transformed infrared spectroscopy, nitrogen adsorption–desorption, and scanning electron microscopy. The catalytic activity of these aluminas in the epoxidation of cis-cyclooctene with aqueous 70 wt% hydrogen peroxide shows, after 24 h, a profile with two maxima at 400 and 700 °C that corresponds to 85 and 80% yield, respectively. However, this profile cannot be directly related to the structural and textural properties of the calcined aluminas. Regarding the hydrophilicities of the calcined aluminas, determined by the amount of water molecules per nm2, the epoxide yield of the aluminas can be segregated into three groups corresponding to the general crystallographic classification of these aluminas: boehmite, γ-series, and δ-series. The aluminas from the γ-series show the highest cyclooctene oxide yield after 1 h; however, due to surface modifications occurring during the reaction, the aluminas from the δ-series also give good yields after 24 h. The water adsorption capacity or hydrophilicity of these aluminas shows a strong correlation with epoxide productivity of the calcined aluminas at 24 h. Generally, better epoxide productivity is observed for lower hydrophilicities. The hydrogen peroxide efficiencies are typically 2.0–2.5 mmol of oxidant per mmol of epoxide formed after 24 h. However, the aluminas of the δ-series show poor efficiency at the beginning of the reaction that improves from an average of 4.1 to 2.3 mmol of oxidant per mmol of epoxide after 2 h due to modification of their surfaces. [Copyright &y& Elsevier]

The structural, textural, and chemical properties as well as the hydrophilicity of four different sol–gel aluminas were determined by different methods and compared with their activity in the catalytic epoxidation of cis-cyclooctene with aqueous H2O2. It was found that the hydrophilicity of the γ-alumina surface is the principal factor responsible for the difference in catalytic activity. The hydrophilicity of γ-alumina should be sufficient to guarantee a fast reaction with hydrogen peroxide on the surface but should not to be too high in order to allow the approach of olefin to the active sites. [Copyright &y& Elsevier]

A significant effort has been done towards the development of new catalysts for the synthesis of epoxides in a more environmental friendly way. We have found that a simple hexaaquoaluminum salt (2 mol% of Al(NO3)3 · 9H2O) is able to catalyze the epoxidation of cis-cyclooctene with high yields using aqueous (70 wt%) hydrogen peroxide. In THF we obtained 98% of conversion with 88% of selectivity for cyclooctene epoxide after 12 h. [Copyright &y& Elsevier]

Katalytische Raffinierung von Biomasse: Über den herkömmlichen Abbau von pflanzlicher Biomasse hinaus zielen aktuelle Prozesse zum katalytischen Aufschluss von Biomasse darauf ab, die Eigenschaften isolierter Biomassebestandteile durch und für die Katalyse rational maßzuschneidern. So kann das Potenzial der Katalyse bei der Umwandlung isolierter Biomassefraktionen in Chemikalien und Brennstoffe vollständig genutzt werden. [ABSTRACT FROM AUTHOR]

Herein a novel class of solvent systems for cellulose is introduced. Surprisingly, organic electrolyte solutions, which contain just a small molar fraction of ionic liquid, dissolve instantaneously large amounts of cellulose. The solvation properties of the solvent systems, required for dissolving the polymer, are discussed here. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented regarding the incidence of deep neck infection among older people.

Facial nerve paralysis associated with parotid gland mass is usually caused by malignant neoplasms and facial nerve dysfunction due to parotid infection is exceedingly rare. A review of the literature revealed ≈ 15 cases of facial nerve palsy associated with suppurative parotitis or parotid abscess. We report the first case of candidal abscess of the parotid gland associated with facial nerve paralysis in a 74-year-old insulin-dependent diabetic patient. The differential diagnosis in these unusual cases occurring in diabetic, immunodeficient patients should include Candida albicans infection. [ABSTRACT FROM AUTHOR]

The author looks at the potential of lignins, one of the main components of non-edible, lignocellulosic biomass, as sustainable raw materials for renewable fuels, chemicals and materials. Topics covered include the importance of ligin for the economic viability of current and future biorefinery operations, the challenges for its efficient valorisation, and the growing interest of the scientific community in lignin's applications and catalytic conversions.

Catalytic biorefining: Beyond the deconstruction of plant biomass, emerging processes for catalytic biomass fractionation are directed towards rationally designing the properties of the isolated biomass components through and for catalysis. The full potential of catalysis in the conversion of the isolated fractions into chemicals and fuels can thus be exploited. [ABSTRACT FROM AUTHOR]

Review: 427 refs. [ABSTRACT FROM AUTHOR]

Abstract: Dilute acid hydrolysis of lignocellulose often requires a neutralisation step to utilise the hydrolysate's sugars. In this context, very little is known regarding the impact of low levels of acids or their corresponding salts produced by neutralisation on the catalyst performance in the hydrogenation of sugars. In this work, the influence of a series of ammonium and alkali metal salts (that is, NH4NO3, NaNO3, (NH4)2SO4, Na2SO4 and K2SO4) on the hydrogenation of glucose and xylose is addressed. This study also encompasses “real‐world” hydrolysates obtained by the mechanocatalytic depolymerisation of α‐cellulose and beechwood. The impact of low levels of acids and their salts upon the hydrogenation of sugars to sugar alcohols (alditols) was examined, in the presence of a commercial Ru/C catalyst (Ru/C, 0.7 wt % Ru) at 110 °C using batch and trickle‐bed reactors. The results show that the presence of salts leads to a considerable decrease in the alditols yields. Notably, salt anions exert an effect stronger than that of cations in the catalyst deactivation. Surprisingly, nitrates had a more significant effect on the decrease in the alditols yield than sulfates, and chlorides had the lowest impact. In this study, we also present the effect of sugars’ degradation products (e.g. 5‐(hydroxymethyl)furfural and furfural) upon hydrogenation of lignocellulose hydrolysates. The activated carbon pre‐treatments of the hydrolysates showed a positive effect on the catalyst activity, adsorbing hydrolysis by‐products. Overall, this study has significant implications for the practical aspects of hydrogenation of lignocellulose hydrolysates, which are often neglected in the current literature. [ABSTRACT FROM AUTHOR]

Solvolytisch aus Biomasse erhaltenes Lignin hat möglicherweise deutlich niedrigere Molekulargewichte als allgemein angenommen. Darauf basierend beschreiben R. Rinaldi und P. Ferrini in ihrer Zuschrift auf S. 8778 ff. eine Methode, die die Isolierung von Lignin als depolymerisiertem Öl ermöglicht und Zellstoffe liefert, die für die enzymatische Hydrolyse geeignet sind. Somit wurde ein Verfahren für die Verwertung von Lignin mittels heterogener Katalyse entwickelt. [ABSTRACT FROM AUTHOR]

Lignin solvolytically released from biomass may be of much lower molecular weights than currently believed. In their Communication on page 8634 ff., R. Rinaldi and P. Ferrini exploit this feature for establishing a method that enables the isolation of lignin as a depolymerized oil and yields pulps amenable to enzymatic hydrolysis. The lignin oil is highly susceptible to hydrogenation under mild conditions, and therefore, a unique pathway for lignin valorization by heterogeneous catalysis has been established. [ABSTRACT FROM AUTHOR]

Mechanocatalysis is an efficient method for deep depolymerization of lignocellulosic materials. It renders full conversion of lignocellulose into water-soluble products, a mixture of oligosaccharides and lignin oligomers. In an aqueous monophasic system, it is known that further saccharification of these products affords high yields of fermentable sugars in addition to a lignin precipitate. Although much attention has been devoted to upgrading of the carbohydrate fraction, the reactivity of mechanocatalytically-isolated lignin has hitherto been overlooked. In this report, we demonstrate the saccharification of water-soluble lignocellulose in a biphasic mixture of water and 2-methyltetrahydrofuran, to prevent lignin fragments from recondensation, not only with other lignin fragments but also with oligosaccharides and their degradation products. The lignin stream extracted in the biphasic system exhibits a molecular weight much lower than that of the lignin precipitate obtained from monophasic aqueous saccharification, and that of lignin isolated by an Organosolv process with no added acid catalyst. Surprisingly, β-O-4 and phenylcoumaran (β-5 + α-O-4) linkages are quantitatively hydrolyzed during saccharification in the biphasic system. However, the extracted lignin still incorporates resinol bonding motifs (β-β + γ-O-α). Because of the lower molecular weight, low carbohydrate content, and high solubility in organic solvents, the catalytic downstream processing of the extracted lignin leads to higher yields of liquid products (e.g. 2-methoxyphenols and 2,6-dimethoxyphenols) by RANEY® Ni-catalyzed hydrogenolysis (200 °C, 7 MPa H2), compared to reactions performed on the lignin precipitate or Organosolv lignin. [ABSTRACT FROM AUTHOR]

Metal dispersion is key for designing highly active and well-defined catalytic systems. Herein, to shed light on the effects of Nb dispersion on the conversion of fructose into HMF, highly porous silica glasses grafted with niobium oxide were prepared. Preliminary catalytic screening was done for the microwave-assisted conversion of fructose into 5-hydroxymethylfurfural (HMF) in a biphasic system. The highly porous silica glasses impregnated with niobium oxide presented HMF productivities about 10- to 20 times higher than the mesoporous NbOPO 4 reference material. Intriguingly, humin formation correlates with HMF yield regardless of the catalyst employed, although metal dispersion influences the acidity profile. [Display omitted] • Highly porous silica glasses allow for high surface dispersion of niobium oxide. • Niobium-containing mesoporous glass catalyzes the dehydration of fructose to HMF. • Fast and efficient conversion of fructose is obtained by microwave irradiation. • Low loading of Nb on the glass matrix allows tailoring Lewis and Brønsted acid sites. [ABSTRACT FROM AUTHOR]

The long-term thermal stability of imidazolium-based ionic liquids is addressed here. We have found that potentiometric titration is a precise, low-cost and quick analytical method to assess the quality changes occurring during the thermal aging of ionic liquids. Using this protocol, we have discovered that imidazolium-based ionic liquids start to decompose, to a small extent, at much lower temperatures than those inferred from thermogravimetric analysis. [ABSTRACT FROM AUTHOR]

A catalytic system capable of reaching high performance in the hydrogenolysis of cellulose at low reaction temperature and short reaction times has been developed. Therefore, supported noble metal catalysts based on Pt, Pd and Ru have been combined with dilute mineral acids. A broad variable set in terms of type of noble metal, type of acid, acid concentration and reaction time could be evaluated based on chemical interpretation and supported by a Design of Experiment (DoE) approach. The variables significantly influenced conversion of cellulose, product range and selectivity towards sugar alcohol formation. Thus, at 160 °C, above 60% yield in sugars and sugar alcohols with 84% selectivity at a cellulose conversion of 72% could be reached. Besides, glycerol, propylene glycol, ethylene glycol and methanol were formed as additional valuable by-products leading to an overall carbon utilization above 89%. Furthermore, the concept was successfully transferred to real feedstocks in the form of spruce reaching close to 60% conversion in only one hour reaction time. [ABSTRACT FROM AUTHOR]

The objective of this study was to assess the progression of atherosclerosis in carotid and femoral arteries after a 5-year period using ultrasound in subjects with chronic hepatitis C and in controls matched for classic atherosclerotic risk factors. A total of 40 patients and 40 controls were assessed by echocolor Doppler in 2001 and in 2006 to evaluate plaque and intima-media thickness. The patients showed no changes in plaque and intima-media thickness during the 5-year period in all districts examined, whereas a significant increase in intima-media thickness in the carotid sections was recorded in the controls. Chronic hepatitis C seems to cause delay in the atherosclerotic process. [ABSTRACT FROM AUTHOR]

High-dose CT (HDCT) is considered the gold-standard imaging for the measurements of skeletal muscle area (SMA), visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT) and intramuscular adipose tissue (IMAT) areas in the abdomen. These parameters may reflect sarcopenia, which can have a prognostic impact in several oncological diseases. The aim of this study was to compare the agreement of measurements of SMA, VAT, SAT and IMAT areas between HDCT and low-dose CT (LDCT) of 18-fludeoxyglucose positron emission tomography (18F-FDG PET)/CT in elderly patients affected by Hodgkin lymphoma (HL). We retrospectively included 90 patients affected by HL who underwent baseline 18F-FDG-PET/CT and HDCT within a mean interval of 7 days. HDCT and LDCT images were analysed by two blinded observers using segmentation software (Slice-O-Matic, Tomovision) to quantify the areas. HDCT and LDCT measurements were compared using Bland–Altman plots and Passing-Bablock regression analyses. Pearson correlation coefficient (r) was used to correlate measurements from the two imaging modalities. Comparison of HDCT and LDCT data demonstrated a strong correlation for measurement of VAT(r = 0.942, p < 0.0001), SAT (r = 0.894, p < 0.0001) and SMA (r = 0.934, p < 0.0001). Instead considering IMAT, correlation was good but less significant (r = 0.742). The mean difference between the two methods was found to be very small, with a difference of 1% for SAT,+6.1% for VAT,+2.5% for SMA and −1.9% for IMAT. LDCT of PET/CT is a safe, accurate and precise method for the measurements of skeletal muscle area, visceral and subcutaneous adipose tissue. Their measurements are reproducible and correlate closely with HDCT. LLDCT of PET/CT is a safe and accurate method for the measurements of SMA, VAT and SAT; their measurements are closely correlated with HDCT. LDCT can be considered an accurate alternative tool for measuring abdominal fat and muscles in the clinical practice. [ABSTRACT FROM AUTHOR]

Abstract: Burkholderia cepacia complex (BCC) has been rarely isolated in infections of the ear, nose and throat region in immunocompetent patients without cystic fibrosis. There is only one previous study in literature that reported BCC isolation in immunocompetent patients with sinonasal polyposis. We describe herein a rare case of multiresistant sinonasal infection by BCC in an immunocompetent patient with recurrent sinonasal polyposis. BCC seems to be a potentially emerging bacterial pathogen of sinonasal structures in patients with polyposis, also after FESS. [Copyright &y& Elsevier]

This study presents an integrated approach combining aqueous phase reforming (APR) and hydrodeoxygenation (HDO) for the hydrotreatment of guaiacol, a model compound representing lignin-derived phenols in pyrolysis bio-oils. The APR process enables in-situ H 2 generation, eliminating the need for an external hydrogen source. We examine the interplay between metal species, the Pt-promoting effect on Ni–Pt catalyst supported on activated carbon (AC), and the choice of hydrogen source (methanol or glycerol). Amongst the monometallic catalysts, a 1% Pt/AC catalyst notably achieved over 96% guaiacol conversion at 300 °C with either hydrogen source. Interestingly, when 0.5–1% of the Ni loading is replaced with Pt, the resulting bimetallic Ni–Pt/AC catalysts demonstrate a significant improvement in guaiacol conversion, reaching 70% when methanol is employed as the hydrogen source. Surprisingly, no comparable enhancement in guaiacol conversion is observed when employing glycerol as the hydrogen source. This observation underlines one of the pivotal effects of the hydrogen source on catalyst performance. X-ray photoemission spectroscopy (XPS) pinpointed strong Ni–Pt interactions in the catalyst. It also revealed distinctive electronic features of Ni–Pt/AC, which are favourable for steering selectivity towards cyclohexanol rather than phenol when Pt loading is increased from 0.5 to 1%. Moreover, Pt enhanced catalyst stability by inhibiting the oxidation of Ni sites and mitigating Ni–Pt phase sintering. Overall, our findings offer important insights into integrating APR and HDO processes, the promotion effect of Pt, and the importance of hydrogen source selection in terms of guaiacol conversion and catalyst stability. [Display omitted] [ABSTRACT FROM AUTHOR]

Hydrodeoxygenation (HDO) of lignocellulose-derived pyrolysis oils offers an option to produce fuel substitutes. However, catalyst deactivation and stability constitute a significant issue. Herein, the dependence of stability and activity of Ni2P/SiO2 HDO catalysts on the support surface polarity is addressed in detail. The support surface polarity was adjusted by copolymerizing tetraethyl orthosilicate (TEOS) with different types and amounts of organosilanes by a sol-gel process in the presence of nickel nitrate and citric acid. After thermal treatment under an inert atmosphere, Ni/SiO2 precursors were formed. They were converted into Ni2P/SiO2 catalysts by using NaH2PO2 as a PH3 source. The catalyst surface polarity was characterized by inverse gas chromatography measurements of the free energy of methanol adsorption, and specific and dispersive surface energies derived from polar and nonpolar probe molecule adsorption. The correlation between catalyst performance and support surface polarity indicates that, to prevent deactivation of the catalyst by water under reaction conditions, the affinity of the support towards polar substances must be decreased below a threshold value. [ABSTRACT FROM AUTHOR]

Difficulties in the recycling of soluble acid catalysts within the lignocellulosic biorefinery constitute a serious issue to the sustainability of cellulose hydrolysis and several other transformations. Herein, we demonstrate a simple and effective method for the removal and recovery of p-toluenesulfonic acid (p-TSA) employed as a replacement of H2SO4 in the saccharification of cellulose by a mechanocatalytic route. p-TSA is recovered from its diluted aqueous solutions using a non-expensive hypercrosslinked polymer adsorbent. In a batch process, around 97% p-TSA acid was removed from a 5 mM solution after exposure to the hypercrosslinked polymer. Notably, a flow-through process was able to selectively remove the catalyst completely from even lower initial concentrations. Importantly, the efficient recovery of the p-TSA is achieved by washing the spent polymer with methanol. In the purification of a stream derived from the saccharification of cellulose, the extraction of p-TSA catalyst in addition to 5-hydroxymethylfurfural (HMF) and furfural was also achieved. With the rational choice of solvents, p-TSA and furfurals were separately recovered. In the broader context, the current findings represent a step forward towards the acid management from the acid-catalyzed saccharification of cellulose. Moreover, this approach is conducive for the purification of sugars for bioconversion in which even low levels of furfurals may exert a strong inhibitory effect upon yeast cultures. [ABSTRACT FROM AUTHOR]

In the broad context of catalysis for lignin valorization, the term "recalcitrance" is often used to describe the resistance of lignin to undergo chemical transformations (generally, reductive processes) rendering small molecules soluble in the reaction medium. Unfortunately, the current usage of the term "recalcitrance" often remains vague in meaning, hindering the search for better catalysts for lignin valorization. In the quest to address the research question--What is lignin recalcitrance?-- we present our search for the factors responsible for the resistance of lignin to reductive catalytic processes, from various perspectives. In this study, lignins isolated as a precipitate obtained from the saccharification of water-soluble lignocelluloses (produced by solvent-free mechanocatalytic depolymerization of beechwood, pinewood, or sugarcane bagasse) and their counterparts isolated by solvent extraction (organosolv pulping) are investigated. The critical analysis of structure and bonding, in addition to the in-depth understanding of results from the catalytic upgrading of lignin streams, in the presence of Raney Ni and H2 pressure under mild and extreme conditions, reveals that the simple evaluation of the total yield of liquid products provides no quantitative measure of the lignin recalcitrance. Our results shed light on the real meaning, origins and implications of "lignin recalcitrance" for catalysis research. The results demonstrate that lignin recalcitrance is associated not only with its intrinsic properties (i.e. molecular weight, the occurrence of native linkages, and their bond dissociation enthalpies) but also with its extrinsic properties (e.g. residual polysaccharides and solubility). Overall, this study presents a detailed evaluation of recalcitrance of lignin through the critical analysis of the product mixture properties (e.g. H/C and O/C ratios, molecular weight distribution, yield of key individual products, and several others). [ABSTRACT FROM AUTHOR]

There are several established approaches for the reductive fractionationof lignocellulose (e.g., “catalytic upstream biorefining" and “lignin-first" approaches) that lead to a lignin oil product that is composed primarily of dihydro-p-monolignols [e.g., 4-(3-hydroxypropyl)-2-methoxyphenol and 4-(3-hydroxypropyl)- 2,6-dimethoxyphenol]. Although effective catalytic methods have been developed to perform reductive or deoxygenativeprocesses on the lignin oil, the influence of the 3-hydroxypropylsubstituent on catalyst activity has previously beenoverlooked. Herein, to better understand the reactivity of thedepolymerized lignin oil obtained from catalytic upstream biorefiningprocesses, dihydro-p-coumaryl alcohol was selected asa model compound. Hydrogenation of this species in the presenceof Raney Ni with molecular hydrogen led to ring saturation(100% selectivity) in the absence of hydrodeoxygenation,whereas under hydrogen-transfer conditions with 2-propanol,hydrogenation occurred (&55% selectivity) simultaneouslywith hydrodeoxygenation (&40% selectivity). In a broadercontext, this study sheds light not only on the reactivity of dihydro-p-monolignols but also on the intricacies of the catalyticupstream biorefining reaction network in which these speciesare revealed to be key intermediates in the formation of less functionalized p-alkylphenols. [ABSTRACT FROM AUTHOR]

A simple and efficient hydrodeoxygenation strategy is described to selectively generate and separate high-value alkylphenols from pyrolysis bio-oil, produced directly from lignocellulosic biomass. The overall process is efficient and only requires low pressures of hydrogen gas (5 bar). Initially, an investigation using model compounds indicates that MoC x/C is a promising catalyst for targeted hydrodeoxygenation, enabling selective retention of the desired Ar−OH substituents. By applying this procedure to pyrolysis bio-oil, the primary products (phenol/4-alkylphenols and hydrocarbons) are easily separable from each other by short-path column chromatography, serving as potential valuable feedstocks for industry. The strategy requires no prior fractionation of the lignocellulosic biomass, no further synthetic steps, and no input of additional (e.g., petrochemical) platform molecules. [ABSTRACT FROM AUTHOR]

A simple and efficient hydrodeoxygenation strategy is described to selectively generate and separate high-value alkylphenols from pyrolysis bio-oil, produced directly from lignocellulosic biomass. The overall process is efficient and only requires low pressures of hydrogen gas (5 bar). Initially, an investigation using model compounds indicates that MoC x/C is a promising catalyst for targeted hydrodeoxygenation, enabling selective retention of the desired Ar−OH substituents. By applying this procedure to pyrolysis bio-oil, the primary products (phenol/4-alkylphenols and hydrocarbons) are easily separable from each other by short-path column chromatography, serving as potential valuable feedstocks for industry. The strategy requires no prior fractionation of the lignocellulosic biomass, no further synthetic steps, and no input of additional (e.g., petrochemical) platform molecules. [ABSTRACT FROM AUTHOR]

Hydrodeoxygenation (HDO) is an attractive route for the upgrading of bio-oils produced from lignocellulose. Current catalysts require harsh conditions to effect HDO, decreasing the process efficiency in terms of energy and carbon balance. Herein we report a novel and facile method for synthesizing bimetallic PtCo nanoparticle catalysts (ca. 1.5 nm) highly dispersed in the framework of nitrogen-doped ordered mesoporous carbon (NOMC) for this reaction. We demonstrate that NOMC with either 2D hexagonal ( p6 m) or 3D cubic ( Im [ABSTRACT FROM AUTHOR]

Hydrodeoxygenation (HDO) is an attractive route for the upgrading of bio-oils produced from lignocellulose. Current catalysts require harsh conditions to effect HDO, decreasing the process efficiency in terms of energy and carbon balance. Herein we report a novel and facile method for synthesizing bimetallic PtCo nanoparticle catalysts (ca. 1.5 nm) highly dispersed in the framework of nitrogen-doped ordered mesoporous carbon (NOMC) for this reaction. We demonstrate that NOMC with either 2D hexagonal ( p6 m) or 3D cubic ( Im [ABSTRACT FROM AUTHOR]

We recently introduced catalytic upstream biorefining, a fractionation process performed on whole lignocellulosic materials, based on the early-stage conversion of lignin by hydrogen-transfer reactions (using Raney Ni as the catalyst and 2-PrOH as a hydrogen-donor). The process fractionates lignocellulose, isolating lignin as an extensively depolymerised oil, opening up new avenues in the catalytic upgrading of bio-derived phenolic streams to chemicals and fuels. In addition, highly delignified holocellulose pulps are obtained, holding potential as a feedstock for the production of paper, chemicals, and biofuels. Herein, we report our first results on the chemistry underlying this process under nearly neutral to slightly alkaline conditions achieved by the addition of inorganic bases. This report sheds light on the influence of hemicellulose sugars on the product distribution obtained from the early-stage catalytic conversion of lignin oligomers released from lignocellulose. The increase in the pH value of the medium suppressed the hydrolysis of xylans. As a result, a dramatic increase in the xylans retention from 10 % (at pH 4.5) up to 60 % (at pH>7.5) was achieved. Interestingly, the pH value of the liquor did not affect the delignification extent of lignocellulose or the absolute content of glucans retained in the holocellulose. By enhancing xylans retention, we provide evidence that hemicellulose sugars decrease the activity of Raney Ni towards full hydrogenation of the aromatic species composing the lignin stream. In fact, the yield of selected cyclohexanols increases from 0.8 % (no added bases) to 4.4 % (added NaOH), whereas the yield of selected phenols decreases from 12.9 % (no added bases) to 7.2 % (added NaOH). [ABSTRACT FROM AUTHOR]