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4 Figuras, 4 Tablas, 1 Esquema.-- This is a post-peer-review, pre-copyedit version of an article published in Wood Science and Technology. The final authenticated version is available online at: http://dx.doi.org/10.1007/s00226-018-1047-5, The fabrication of activated carbon (AC) is widely carried out by the so-called chemical activation method, in which the biomass substratum is put in touch with an impregnating chemical agent prior to the carbonization stage. Even though this methodology is known for a long time, there are many features that are still poorly understood, particularly those regarding the details of the underlying mechanisms involved during the interaction of the activating agent with the precursor, eventually leading to the development of AC. Previous research conducted in the laboratories dealt with the use of cherry stones (CS) and phosphoric acid, toward ACs with tailored porous structures, finding out that the experimental variables of the impregnation stage were crucial for their eventual characteristics. Thus, the results obtained at that time deserved further discussion, with the aim at unraveling the true nature of those findings. With such purpose, the authors comment further on the CS and H3PO4 in non-conventional impregnation methodologies, performed in the previous works. Four series of H3PO4-impregnated products were prepared in a previous research, using a wide range of impregnation strategies, aiming at controlling the loading of H3PO4 on the lignocellulosic substratum. Herein, with the mass uptake as the main, it was possible to link the uptake with the chemical changes of H3PO4 in agreement with essential chemistry knowledge. Mass gain is strongly dependent on the impregnation method, and interesting insights arise on the basis of the mass changes of CS after impregnation., Financial support by Gobierno de Extremadura and European FEDER Funds are gratefully acknowledged. Special thanks are directed toward Mr. Patrick Moosbrugger for his kind support on visual designing.

Lignocellulosic materials are good precursors for the production of activated carbon. In this work, chestnut wood has been used in the preparation of activated carbon by the method of phosphoric acid-chemical activation. The influence of heat treatment temperature (i.e., 300, 400, 500 and 600 °C) and concentration of the solution of phosphoric acid (i.e., 1:1, 1:2 and 1:3 water/H 3 PO 4 proportions) used in the impregnation of chestnut wood on textural properties and fractal dimension has been studied. The products obtained have been characterized by N 2 adsorption at −196 °C. The activated carbons are mainly microporous products, both the micropore volume ( V mi ) and the specific surface area ( S BET ) as a rule increasing with increasing temperature and acid concentration. However, V mi and S BET decrease at 600 °C with regard to 500 °C. The micropore size distribution is similar in the products prepared at 400 and 500 °C, regardless of the acid concentration. For the carbons obtained at the other temperatures, the microporous structure is more heterogeneous for the 1:3 concentration at 300 °C and for the 1:1 and 1:2 concentrations at 600 °C. Similar trends to those shown by V mi and S BET are usually observed for the fractal dimension.

Five low-rank coals, including leonardites and lignites, have been physico-chemically characterised. The effects of the carbonisation and demineralisation of some coals on mass and physical properties have also been studied. The characterisation was carried out by the chemical analyses of the coals and also by Fourier transform infrared (FT-IR) spectroscopy, gas adsorption (N2, 196 8C; CO2 ,0 8C), mercury porosimetry, and density measurements. The contents of moisture, volatile matter, oxygen, carboxylic acids, and carbon–carbon double bondcontaining structures are higher in leonardites than in lignites. The degree of development of surface area and microporosity is small for all coals. All samples appear to possess constrictions in micropores. The mesopore volume is significantly higher for a number of coals. The carbonisation and demineralisation of the coals produce a marked increase in the open porosity. D 2004 Elsevier B.V. All rights reserved.

We report the case of a 31 year old male with presumed cryptococcal choroiditis associated with cryptococcal meningitis and AIDS. Multiple yellowish-whitish small choroidal lesions, retinal hemorrhages and cotton-wool spots appeared in the posterior pole associated with vision loss. We also carried out differential diagnosis with other frequent diseases and a review of the treatments.Cryptococcus neoformans is an opportunistic fungus with a predilection for infecting the meninges in patients with Acquired Immunodeficiency Syndrome AIDS (10%). Ocular manifestation usually includes cranial nerve palsies or papilledema secondary to increased intracranial pressure. Cryptococcal choroiditis is less frequent (5% of patients with meningitis).

espanolObjetivo/Metodo: Presentamos el caso de un paciente de 31 anos con presunta coroiditis criptococica que ocurrio en el seno de una meningitis criptococica y SIDA. Multiples lesiones pequenas blanco-amarillentas aparecieron bilateralmente en coroides, asi como abundantes hemorragias y exudados algodonosos asociados a disminucion de agudeza visual. Tambien realizamos diagnostico diferencial con otras entidades frecuentes y revision de los tratamientos. Resultados/Conclusiones: Criptococos neoformans es un hongo oportunista con predileccion por afectacion meningea en SIDA (10%). Las manifestaciones oculares normalmente son por afectacion de los pares craneales o por papiledema secundario al aumento de presion intracraneal (hasta en un 50% de los casos). La coroiditis criptococica ocurre menos frecuentemente (5% de pacientes con meningitis). EnglishPurpose/Methods: We report the case of a 31 year old male with presumed cryptococcal choroiditis associated with cryptococcal meningitis and AIDS. Multiple yellowish-whitish small choroidal lesions, retinal hemorrhages and cotton-wool spots appeared in the posterior pole associated with vision loss. We also carried out differential diagnosis with other frequent diseases and a review of the treatments. Results/Conclusions: Cryptococcus neoformans is an opportunistic fungus with a predilection for infecting the meninges in patients with Acquired Immunodeficiency Syndrome AIDS (10%). Ocular manifestation usually includes cranial nerve palsies or papilledema secondary to increased intracranial pressure. Cryptococcal choroiditis is less frequent (5% of patients with meningitis).

We describe an acute retinal pigment epithelitis (A.R.P.E) case in a young woman who noticed an acute decreased vision and color vision defects. The patient was treated with systemic nonsteroidal anti-inflammatory drugs (NSAIDs) with recovery of visual acuity to normal in three weeks.We highlight the debut with important decrease of visual acuity at levels that are not common in this illness. The disturbance in color vision is a rare symptom. The visual acuity recovery in a short period of time is what usually happens, and in this case it is just three weeks, not knowing how it relates to NSAID.