Mild alkaline separation of fiber bundles from eucalyptus bark and their composites with cellulose acetate butyrate

High surface lignin content (i.e. 34.6 %) sclerenchyma fiber bundles were successfully isolated with a yield of 71 % by a mild alkali (NaOH dosage of 5 wt%) extraction of eucalyptus (Eucalyptus globulus) bark under 100 degrees C for 60 min.. The mechanical properties of the composites prepared by hot pressing of cellulose acetate butyrate (CAB) sheets with the fiber bundles were evaluated. The fiber bundles exhibited good compatibility with CAB due to their hydrophobic fiber surfaces. The mechanical properties of the fiber bundle/ cellulose acetate butyrate composites revealed the maximum at a weight ratio of 25:75, which demonstrates the promise of utilizing these isotropic aligned fiber bundles as the reinforcement to the cellulose acetate butyrate without the addition of plasticizers for composite uses.Peer reviewe

Open coating with natural wax particles enables scalable, non-toxic hydrophobation of cellulose-based textiles

Environmental benign cellulosic textiles are hampered by their tendency to absorb water, which restricts their use in functional clothing. Herein we describe a method to functionalize textile surfaces using thin, open coatings based on natural wax particles and natural polymers rendering cellulosic fabrics water-repellent while retaining their feel and breathability. The impact of curing temperature, cationic polymer and fabric properties on wetting and long-term water-repellency were studied using contact angle measurements and scanning electron microscopy. The wetting properties were correlated to roughness of the textiles using white light interferometer. X-ray photoelectron spectroscopy revealed the surface chemical composition, leading to fundamental understanding of the effect of annealing on the wax layer. Breathability was evaluated by water vapor permeability. The optimal curing temperature was 70 °C. The developed coating performed well on different natural textiles, and better than commercial alternatives. A set of garment prototypes were produced using the coating.Peer reviewe

Occurrence of Reverse Side Effects in Corona Treatment of Dispersion-Coated Paperboard and Its Influence on Grease Barrier Properties

The uncoated side of dispersion-barrier-coated paperboards was exposed to positive and negative direct current corona treatments in order to confirm the occurrence of backside treatment and clarify its effects on the usability of the paperboard. The main component of the coating dispersions was hydroxypropylated potato starch and the effects of talc and styrene-butadiene latex additions on backside treatment were evaluated. Coatings with a high talc proportion showed excellent initial grease resistance, but corona-induced strikethroughs caused a drastic decrease in grease penetration time. The root-mean-square roughness measurements revealed moderate surface roughening at the backside, indicating thus backside treatment. The alterations in surface free energies and rapeseed oil contact angles confirmed the occurrence of backside treatment. The high polarization potential of latex played a key role in these observations. At the same time, the inertity of talc had a stabilizing effect but it did not prevent backside treatment completely. X-ray photoelectron spectroscopy results verified that backside treatment occurs also when the barrier-coated side of the substrate is treated with corona, indicating that a dispersion coating layer does not prevent this undesired phenomenon. Bearing in mind that expressing customized information or including personalized elements in food packages or disposable cups and plates is under great interest, it can be assumed the exposure of packaging materials to corona will become more common in the near future, and the need for optimizing bio-based packaging materials for such purposes is obvious

Superhydrophobic Paper from Nanostructured Fluorinated Cellulose Esters

The development of economically and ecologically viable strategies for sup erhydrophobization offers a vast variety of interesting applications in self-cleaning surfaces. Examples include packaging materials, textiles, outdoor clothing, and microfluidic devices. In this work, we produced superhydrophobic paper by spin-coating a dispersion of nanostructured fluorinated cellulose esters. Modification of cellulose nanocrystals was accomplished using 2H,2H,3H,3H-perfluorononanoyl chloride and 2H,2H,3H,3H-perfluoroundecanoyl chloride, which are well-known for their ability to reduce surface energy. A stable dispersion of nanospherical fluorinated cellulose ester was obtained by using the nanoprecipitation technique. The hydrophobized fluorinated cellulose esters were characterized by both solid- and liquid-state nuclear magnetic resonance, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and contact angle measurements. Further, we investigated the size, shape, and structure morphology of nanostructured fluorinated cellulose esters by dynamic light scattering, scanning electron microscopy, and X-ray diffraction measurements.Peer reviewe

Aptitud del suelo para cultivo de mango vallenato en guacoche, departamento del cesar

The ability of the "La Estancia" farm soil in Guacoche, Cesar state, for growing Vallenato mango (Mangifera indica L.) was evaluated. One hectare of soil was sampled with 16 pits to define the modal soil profile and describe its properties. Physicochemical analysis were carried out to disturbed and not disturbed samples from each horizon under the methodology reported in the Manual No. 47 del Instituto Colombiano Agropecuario and the methodology established by the Agustín Codazzi Geographical Institute (ACGI). According to the properties and the guide of Keys to Soil Taxonomy de los Estados Unidos, the soil was classified as a Typic Dystrustepts, sandy loam mixed isohyperthermic, of medium fertility., The soil does not have limitation for salts, sodium, or aluminum; locally the soil has high water tables that can cause root rot and facilitate the loss of fertilizer with edaphic application.Se evaluó la aptitud del suelo de la Finca “La Estancia” ubicada en Guacoche, departamento del Cesar, para el cultivo de mango (Mangifera indica L.) variedad Vallenato. Se muestreó una hectárea de suelo con 16 calicatas para definir el perfil modal del suelo y describir sus propiedades. Se tomaron muestras disturbadas y no disturbadas de cada horizonte para análisis fisicoquímico según Manual No. 47 del Instituto Colombiano Agropecuario y la metodología establecida por el Instituto Geográfico Agustín Codazzi (IGAC). El suelo fue clasificado como un Typic Dystrustepts, arenoso franco mixto isohipertérmico, de mediana fertilidad, según Claves de Taxonomía de Suelos de los Estados Unidos. El suelo no tiene limitaciones por sales, sodio o aluminio; localmente presentan niveles freáticos altos que pueden ocasionar pudrición de la raíz y facilitar la pérdida de fertilizantes con aplicación edáfica

Dehydroabietylamine-Based Cellulose Nanofibril Films: A New Class of Sustainable Biomaterials for Highly Efficient, Broad-Spectrum Antimicrobial Effects

The design of antimicrobial surfaces as integral parts of advanced biomaterials is nowadays a high research priority, as the accumulation of microorganisms on surfaces inflicts substantial costs on the health and industry sectors. At present, there is a growing interest in designing functional materials from polymers abundant in nature, such as cellulose, that combine sustainability with outstanding mechanical properties and economic production. There is also the need to find suitable replacements for antimicrobial silver-based agents due to environmental toxicity and spread of resistance to metal antimicrobials. Herein we report the unprecedented decoration of cellulose nanofibril (CNF) films with dehydroabietylamine 1 (CNF-CMC-1), to give an innovative contact-active surface active against Gram-positive and Gram-negative bacteria including the methicillin-resistant S. aureus MRSA14TK301, with low potential to spread resistance and good biocompatibility, all achieved with low surface coverage. CNF-CMC-1 was particularly effective against S. aureus ATCC12528, causing virtually complete reduction of the total cells from 10 5 colony forming units (CFU)/mL bacterial suspensions, after 24 h of contact. This gentle chemical modification of the surface of CNF fully retained the beneficial properties of the original film, including moisture buffering and strength, relevant in many potential applications. Our originally designed surface represents a new class of ecofriendly biomaterials that optimizes the performance of CNF by adding antimicrobial properties without the need for environmentally toxic silver. © Copyright 2019 American Chemical Society

СОВРЕМЕННЫЕ ПОДХОДЫ К ПАТОГЕНЕЗУ ЛЕЙОМИОМЫ МАТКИ, ОСЛОЖНЕННОЙ МАТОЧНЫМ КРОВОТЕЧЕНИЕМ (ОБЗОР ЛИТЕРАТУРЫ)

ABSTRACT. The article describes the basic pathogenetic mechanisms of uterine bleeding occurrence in patients with uterine leiomyoma (UL). The pathogenesis of this disease is difficult and multi-factorial. Significant changes in the architectonics of the uterine vasculature are noted. Modern approaches to management of patients with UL and uterine bleeding are discussed from a clinical point of view using conservative, minimally invasive and surgical methods of treatment. РЕЗЮМЕ. В статье изложены основные патогенетические звенья возникновения маточных кровотечений у больных с лейомиомой матки (ЛМ). Патогенез данной патологии представляется сложным и многофакторным. Отмечены выраженные изменения в архитектонике сосудистой сети матки. С клинических позиций рассмотрены современные подходы к тактике ведения больных с ЛМ с маточными кровотечениями с применением консервативных, мини-инвазивных и хирургических методов лечения.

Dehydroabietylamine-Based Cellulose Nanofibril Films : A New Class of Sustainable Biomaterials for Highly Efficient, Broad-Spectrum Antimicrobial Effects

The design of antimicrobial surfaces as integral parts of advanced biomaterials is nowadays a high research priority, as the accumulation of microorganisms on surfaces inflicts substantial costs on the health and industry sectors. At present, there is a growing interest in designing functional materials from polymers abundant in nature, such as cellulose, that combine sustainability with outstanding mechanical properties and economic production. There is also the need to find suitable replacements for antimicrobial silver-based agents due to environmental toxicity and spread of resistance to metal antimicrobials. Herein we report the unprecedented decoration of cellulose nanofibril (CNF) films with dehydroabietylamine 1 (CNF-CMC-1), to give an innovative contact-active surface active against Gram-positive and Gram-negative bacteria including the methicillin-resistant S. aureus MRSA14TK301, with low potential to spread resistance and good biocompatibility, all achieved with low surface coverage. CNF-CMC-1 was particularly effective against S. aureus ATCC12528, causing virtually complete reduction of the total cells from 10(5) colony forming units (CFU)/mL bacterial suspensions, after 24 h of contact. This gentle chemical modification of the surface of CNF fully retained the beneficial properties of the original film, including moisture buffering and strength, relevant in many potential applications. Our originally designed surface represents a new class of ecofriendly biomaterials that optimizes the performance of CNF by adding antimicrobial properties without the need for environmentally toxic silver.Peer reviewe

Amorphous carbon thin film electrodes with intrinsic Pt-gradient for hydrogen peroxide detection

Nanoscale amorphous carbon thin films with intrinsic Pt gradient show great promise as new electrode materials for electrochemical detection of hydrogen peroxide. Embedding the Pt particles in the carbon matrix during the fabrication process allows tighter integration than, for example, adding them after the fabrication on top of the substrate. Especially, this approach can offer excellent electrochemical properties combined with CMOS compatibility, which is crucial for further device development. Here we provide extensive in depth electrochemical and physicochemical characterization of these novel materials by cyclic voltammetry (CV), chronoamperometry (CA), rotating disk electrode (RDE) experiments, transmission electron microscopy (TEM), Raman spectroscopy, x-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). Equipped with these detailed results on these materials we proceed to present some suggestions how the physicochemical properties correlate with the results from electrochemical measurements. (i) It is shown that coarsening of the initially very finely dispersed structure occurs both under electron bombardment during TEM imaging as well as during cyclic voltammetry in H2SO4. (ii) Further, it is shown that OH is adsorbed on small Pt islands much more strongly compared to the bulk Pt, which may heavily influence hydrogen peroxide redox reactions on these Pt-containing amorphous carbon films. (iii) Finally, we proceed to demonstrate that despite these complications, these materials show linear response for hydrogen peroxide reduction in neutral phosphate buffered saline combined with very fast response times.Academy of Finland (E.P. grant #274670, T.L. grants # 285015 and #285526), Biocentrum Helsinki, Finnish Cultural Foundation (N.I. grant #00160331) and Foundation for Aalto University Science and Technology are acknowledged for funding