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In this study, we investigate the spin-momentum locking phenomenon on Rashba states of antimony (Sb) films. Utilizing spin pumping in conjunction with an external charge current, we uncover the topological properties of Sb surface states. Our key finding is the precise manipulation of the direction and magnitude of the charge current generated by the inverse Rashba-Edelstein effect. This control is achieved through the dynamic interaction between out-of-equilibrium pumped spins and spin-momentum-locked flowing spins, which are perpendicular to the charge current. Our results highlight Sb as a promising material for both fundamental and applied spintronics research. The studied Sb nanostructures demonstrate potential for the development of low-power logic gates operating with currents in the microampere range, paving the way for advanced spintronic applications.
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Huntington's disease (HD), one of >50 inherited repeat expansion disorders (Depienne and Mandel, 2021), is a dominantly-inherited neurodegenerative disease caused by a CAG expansion in HTT (The Huntington's Disease Collaborative Research Group, 1993). Inherited CAG repeat length is the primary determinant of age of onset, with human genetic studies underscoring that the property driving disease is the CAG length-dependent propensity of the repeat to further expand in brain (Swami et al ., 2009; GeM-HD, 2015; Hensman Moss et al ., 2017; Ciosi et al ., 2019; GeM-HD, 2019; Hong et al ., 2021). Routes to slowing somatic CAG expansion therefore hold great promise for disease-modifying therapies. Several DNA repair genes, notably in the mismatch repair (MMR) pathway, modify somatic expansion in HD mouse models (Wheeler and Dion, 2021). To identify novel modifiers of somatic expansion, we have used CRISPR-Cas9 editing in HD knock-in mice to enable in vivo screening of expansion-modifier candidates at scale. This has included testing of HD onset modifier genes emerging from human genome-wide association studies (GWAS), as well as interactions between modifier genes, thereby providing new insight into pathways underlying CAG expansion and potential therapeutic targets.
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BACKGROUND: De novo mutations (DNMs) are variants that occur anew in the offspring of noncarrier parents. They are not inherited from either parent but rather result from endogenous mutational processes involving errors of DNA repair/replication. These spontaneous errors play a significant role in the causation of genetic disorders, and their importance in the context of molecular diagnostic medicine has become steadily more apparent as more DNMs have been reported in the literature. In this study, we examined 46,489 disease-associated DNMs annotated by the Human Gene Mutation Database (HGMD) to ascertain their distribution across gene and disease categories. RESULTS: Most disease-associated DNMs reported to date are found to be associated with developmental and psychiatric disorders, a reflection of the focus of sequencing efforts over the last decade. Of the 13,277 human genes in which DNMs have so far been found, the top-10 genes with the highest proportions of DNM relative to gene size were H3-3 A, DDX3X, CSNK2B, PURA, ZC4H2, STXBP1, SCN1A, SATB2, H3-3B and TUBA1A. The distribution of CADD and REVEL scores for both disease-associated DNMs and those mutations not reported to be de novo revealed a trend towards higher deleteriousness for DNMs, consistent with the likely lower selection pressure impacting them. This contrasts with the non-DNMs, which are presumed to have been subject to continuous negative selection over multiple generations. CONCLUSION: This meta-analysis provides important information on the occurrence and distribution of disease-associated DNMs in association with heritable disease and should make a significant contribution to our understanding of this major type of mutation.
Sujet(s)
Cellules germinales , Parents , Humains , MutationRÉSUMÉ
A anquilose da articulação temporomandibular (ATM) é caracterizada pela união intracapsular do complexo disco-côndilo à superfície do osso temporal, podendo gerar restrição dos movimentos mandibulares e limitação de abertura bucal. São descritas ainda alterações como restrição da capacidade mastigatória, dificuldade de fonação e de uma adequada higiene bucal, além de dificuldade de interação social. O presente caso retrata um paciente feminino, 27 anos, com histórico de fratura de parassínfise e côndilo mandibular bilateral após trauma em 2014, evoluindo com anquilose da ATM direita, com abertura máxima de 13,27 mm. Para o tratamento do caso descrito, foi utilizado o acesso de Al-Kayat, coronoidectomia ipsilateral e ressecção de massa anquilótica em gap com interposição de retalho da fáscia do músculo temporal no lado direito. Após seis meses do procedimento cirúrgico, foi realizada uma nova tomografia da face na qual se observa ausência de lesões e de sinais de recidiva da anquilose e também foi observada a manutenção do espaço de lacuna feita pela ressecção óssea. O resultado satisfatório da técnica foi atribuído pela obtenção e estabilização de uma abertura bucal adequada, melhora da capacidade mastigatória e da fonação. Além do sucesso clínico, uma vantagem da técnica utilizada foi o baixo custo do procedimento por utilizar apenas interposição do músculo temporal sem uso de materiais aloplásticos. Além disso, a coronoidectomia ipsilateral associada foi suficiente para auxiliar na manutenção da abertura alcançada, não sendo necessária a coronoidectomia contralateral, o que minimizou o tempo operatório e a morbidade de mais um sítio cirúrgico acessado.
Ankylosis of the temporomandibular joint (TMJ) is characterized by the intracapsular union of the condyle- disc complex to the surface of the temporal bone, which can cause restriction of the mandibular movements and a limitation of a mouth opening. Alterations are also described as a restriction of masticatory capacity, difficulty in phonation and suitable oral hygiene, as well as difficulty in social interaction. A 27-year-old female patient with a bilateral history of parasymphysis and mandibular condyle fracture after a trauma in 2014, which evolved to an ankylosis of the right TMJ, with a maximum mouth opening of 13.27 mm. For the treatment of the described case, it was used the Al- Kayat approach, ipsilateral coronoidectomy and resection of the ankylotic mass in gap with interposition of temporalis muscle fascia flap on the right side. After six months of the surgical procedure, it was made a new computed tomography of the face in which it was possible to notice the absence of lesions and signs of recurrence of the ankylosis. It was also observed the maintenance of the gap space made by the bone resection. The satisfactory result of the technique was attributed to the achievement and stabilization of an adequate mouth opening, improved chewing ability and phonation. Besides the clinical success, an advantage of the technique used was the low cost of the procedure by using only temporal muscle interposition without the use of alloplastic materials. In addition, the associated ipsilateral coronoidectomy was sufficient to help maintaining the achieved mouth opening, and the contralateral coronoidectomy was not necessary, as a result it was minimized the surgical time and morbidity of one more accessed surgical site.
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The combination of biomaterials and bioactive particles has shown to be a successful strategy to fabricate electrospun scaffolds for bone tissue engineering. Among the range of bioactive particles, hydroxyapatite and mesoporous bioactive glasses (MBGs) have been widely used for their osteoconductive and osteoinductive properties. Yet, the comparison between the chemical and mechanical characteristics as well as the biological performances of these particle-containing scaffolds have been characterized to a limited extent. In this work, we fabricated PEOT/PBT-based composite scaffolds incorporating either nanohydroxyapatite (nHA), strontium-containing nanohydroxyapatite (nHA_Sr) or MBGs doped with strontium ions up to 15 wt./vol% and 12,5 wt./vol% for nHA and MBG, respectively. The composite scaffolds presented a homogeneous particle distribution. Morphological, chemical and mechanical analysis revealed that the introduction of particles into the electrospun meshes caused a decrease in the fiber diameter and mechanical properties, yet maintaining the hydrophilic nature of the scaffolds. The Sr2+ release profile differed according to the considered system, observing a 35-day slowly decreasing release from strontium-containing nHA scaffolds, whereas MBG-based scaffolds showed a strong burst release in the first week. In vitro, culture of human bone marrow-derived mesenchymal stromal cells (hMSCs) on composite scaffolds demonstrated excellent cell adhesion and proliferation. In maintenance and osteogenic media, all composite scaffolds showed high mineralization as well as expression of Col I and OCN compared to PEOT/PBT scaffolds, suggesting their ability to boost bone formation even without osteogenic factors. The presence of strontium led to an increase in collagen secretion and matrix mineralization in osteogenic medium, while gene expression analysis showed that hMSCs cultured on nHA-based scaffolds had a higher expression of OCN, ALP and RUNX2 compared to cells cultured on nHA_Sr scaffolds in osteogenic medium. Yet, cells cultured on MBGs-based scaffolds showed a higher gene expression of COL1, ALP, RUNX2 and BMP2 in osteogenic medium compared to nHA-based scaffolds, which is hypothesized to lead to high osteoinductivity in long term cultures.
Sujet(s)
Sous-unité alpha 1 du facteur CBF , Structures d'échafaudage tissulaires , Humains , Structures d'échafaudage tissulaires/composition chimique , Sous-unité alpha 1 du facteur CBF/métabolisme , Strontium/pharmacologie , Différenciation cellulaire , Régénération osseuseRÉSUMÉ
This paper aims to discuss the implications of body talk and socio-cultural pressure for the internalisation of a thin body image in purchase decisions, shopping habits and other outcomes of body dissatisfaction, in particular the proneness to avoid human/social interaction in retail contexts and proneness to engage in corrective, compensatory or compulsive shopping behaviour. This paper conducted an online questionnaire that measured the following constructs: body mass index; Socio-cultural Attitudes Towards Appearance Scale-4 (SATAQ-4), Body Appreciation Scale (BAS-2), Acceptance of Cosmetic Surgery Scale (ACSS), Compulsive Buying Follow-up Scale (CBFS), proneness to avoid social interaction in retail contexts, and the intention to purchase a list of products and services as a compensation for body dissatisfaction. A structural equations model supported the hypotheses proposing the influence of BAS-2 and SATAQ-4 (the internalisation of thin/athletic body and the social comparison induced by family, peers and media) upon the outcomes of social-interaction avoidance, ACSS and CBFS. Nevertheless, BAS-2 only influences social-interaction avoidance. This paper provides several recommendations to brand managers highlighting the social responsibility role of brand advertising in enhancing positive body appreciation, mitigating the psychological damage caused by socio-cultural pressure and preventing the stigmatisation bias against obese people.
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Image du corps , Interaction sociale , Humains , Indice de masse corporelle , Attitude , Enquêtes et questionnaires , Comportement compulsifRÉSUMÉ
Atrazine is an herbicide used worldwide, and it is considered a severe environmental contaminant. The present study aims to evaluate the atrazine adsorption in aqueous media in montmorillonite samples which were either in natural state or functionalized through saturation with lithium and pillarization with aluminum by different methods. Montmorillonite saturated with lithium adsorbed significantly more atrazine than the natural montmorillonite sample. Among the samples obtained through the three aluminum-pillarization methods, the mass percentage of adsorbed atrazine was very similar. However, the best combination was the aluminum-pillarization (due to the maintenance of the open interlayer region) and saturation with lithium (due to the significant reduction of the cation exchange capacity of the mineral), because both processes facilitate the interaction of atrazine with the montmorillonite. Another advantage was that the adsorption of atrazine in the pillared and lithium saturated samples had small desorption, which is desirable in the environmental perspective. It is recommended to build filters with aluminum-hydroxy pillared, lithium saturated montmorillonite as an alternative method to rapidly remove atrazine from aqueous media. In addition to the shorter production time, this process resulted in montmorillonite with high occupancy rate and stability of the aluminum-hydroxy pillars.
Sujet(s)
Atrazine , Bentonite , Adsorption , Aluminium , LithiumRÉSUMÉ
The highly nutritional caja fruit (Spondias mombin L.) is an accessible source of vitamins and antioxidants that are indispensable for the human diet. The objective of the present work was to study the production of a probiotic caja pulp using Bifidobacterium animalis ssp. lactis B94. Firstly, a kinetic study was performed on the fermentation of the caja pulp with Bifidobacterium animalis ssp. lactis B94 to determine the optimum conditions of the process. Growth kinetics revealed that the ideal time for ending the fermentation would be at 22 h because it corresponds to the end of the exponential phase. Both the whole pulp and the probiotic pulp were characterized for pH, acidity, total soluble solids, water content, phenolic content, reducing carbohydrates, ascorbic acid, and total carotenoids. Physicochemical characterization revealed similar results between the whole and the probiotic pulp. The stability test demonstrated that the probiotic pulp is stable and preserved the probiotic attributes of the final product. In conclusion, our results reveal that caja pulp can be considered a favorable medium for the Bifidobacterium animalis ssp. lactis B94 growth and consequently can be explored biotechnologically for new food products.
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Despite technological advances in the production processes of the materials for ceramic façade coatings, the problems of detachments are still frequent. Therefore, this work aims to investigate, through a literature review, the existing gaps related to the adhesion ability of adhesive mortars, identifying new research needs that can better explain the behavior of the material. In addition, an experimental procedure was developed to evaluate the mechanical capacity of adhesive mortars when subjected to cyclic stresses. Dynamic stress measurements are presented for several blocks of mortar and on similar blocks but with a slot drilled prior to measurements (intended to represent failure). From these data we calculated values of stress energy, elastic energy, and dissipated energy. The experimental results showed that the energy involved in the test process accompanied the load values and current stress values. The mortar samples with the previous failure absorbed and dissipated less energy than mortars without failure, showing that materials that have less energy to dissipate, are materials that have developed less capacity to adhere, that is, to keep their parts together.
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The understanding of the mechanical fixation behavior of coatings is crucial for a better comprehension of the bonding systems, especially at the interface between the mortar and the substrate. Physical adherence is related, among other things, to the contents of the materials used in the roughcast and mortar coatings, due to the colloidal water penetration into the pores of the substrate. This work evaluated the influence of different lime solution additions replacing the kneading water in the preparation of roughcast and mortar coatings. Two types of substrates were investigated:ceramic bricks and concrete blocks. Three wall masonry panels were constructed, with dimensions of 220 × 180 cm2, one of concrete block and two of ceramic bricks, followed by the application of roughcast and mortar coating with an average thickness of 5 mm and 20 mm, respectively. Direct tensile bond strength tests were performed and the results, with a 95% confidence level, showed that substrate ceramic and treatment in the roughcast exhibited a better behavior regarding the distribution of the tensile bond strength of the tested specimens. However, no significant differences of the amount of addition used (0%, 5%, 10% and 15%) on the tensile bond strength were observed.
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Introduction: The Cabo Verde Telemedicine program (CVTP) was established by the International Virtual e-Hospital Foundation using the Initiate-Build-Operate-Transfer strategy to improve access to specialty care for the population in the archipelago of Cabo Verde in 2012. Since its inception, the CVTP has proven a great success story of telemedicine in Africa. Our first report on the initial results of a nationwide CVTP was published in 2014. The aim of this article is to analyze the follow-up data and analyze the activity of CVTP. Methods: All telemedicine consultations of the CVTP from 2014 to 2018 were analyzed. Patient demographics, clinical discipline, and transfer status were analyzed. Categorical variables were compared with a chi-squared test. Results: There were 2,442 telemedicine consultations in 24 clinical programs performed during the study period. The most common clinical disciplines with >100 consultations were neurology, cardiology, orthopedic surgery, general surgery, endocrinology, otolaryngology, urology, and dermatology. Overall, the transfer rate was 34.3%. Conclusion: The nationwide CVTP continues to increase access to specialized care, prevent unnecessary and costly transfers, and has become a great success story of telemedicine in Africa. Moreover, this program should serve as a model for establishing island-nations telemedicine programs worldwide.
Sujet(s)
Consultation à distance , Télémédecine , Afrique , Cap-Vert , HumainsRÉSUMÉ
OBJECTIVE: to evaluate the oral health condition of pregnant/postpartum women attending public services in the city of Feira de Santana, BA, Brazil, at three different times between 2005 and 2015. METHODS: this is a study socioeconomic and demographic characteristics, health condition and health care, lifestyle and oral health status of 1,245 participants obtained from a database of three previous investigations: I Intervention Study (2005-2007); II Case-Control Study (2010-2011); III Case-Control Study (2012-2015). RESULTS: comparing the three periods, the frequency of gingivitis (24.41% versus 8.90% versus 5.77%; p<0.01) and periodontitis (44.64% vs 9.16% vs 11.55%; p<0.01) was found to decrease; the worst dental conditions regarding the number of teeth present, healthy and extracted and the DMFT index were found in period III compared to period II. CONCLUSION: an improvement was seen in the participants' periodontal condition over time, which coincides with the implementation of policies pertaining to women's health, oral health and income redistribution in this city.
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Gingivite/épidémiologie , Santé buccodentaire , Parodontite/épidémiologie , Complications de la grossesse/épidémiologie , Adolescent , Adulte , Brésil/épidémiologie , Études cas-témoins , Indice DCAO , Femelle , Politique de santé , État de santé , Humains , Mode de vie , Période du postpartum , Grossesse , Facteurs temps , Jeune adulteRÉSUMÉ
Muitos profissionais ficam confusos quando um dente tem lesão periapical e mantém a vitalidade pulpar. Muitas lesões imitam imagiologicamente as lesões periapicais crônicas inflamatórias e os dentes permanecem com vitalidade pulpar. Sempre devemos lembrar que: 1) dentes com vitalidade pulpar não devem ser abertos sem um diagnóstico prévio das lesões que são portadores; tratamento endodôntico não deve ser aplicado como meio de diagnóstico ou teste terapêutico de lesões periapicais em dentes com vitalidade pulpar. 2) Realizar tratamentos endodônticos em dentes com vitalidade pulpar e com lesões que imitam periapicopatias pode prolongar o tempo de uma abordagem adequada e piorar em muito o prognóstico da lesão. 3) Em dentes com vitalidade pulpar e lesões periapicais de origem a determinar, é muito importante a inter-relação clínica, imagiológica e microscópica para a troca de experiências e conhecimento, visando um diagnóstico seguro e terapêutica eficaz. 4) As lesões relacionadas devem ser mentalizadas ou anotadas para que se aplique sempre frente a dentes com lesões periapicais e com vitalidade pulpar!
Sujet(s)
Humains , Pulpe dentaire , Maladies périapicales/diagnostic , Maladies périapicales/thérapie , Couronne dentaireRÉSUMÉ
Objetivo: avaliar a condição bucal de gestantes e puérperas, usuárias de serviços públicos de saúde de Feira de Santana, BA, Brasil, em três momentos distintos do período 2005-2015. Métodos: estudo sobre características socioeconômico-demográficas, condição e cuidado com a saúde, estilo de vida e condição bucal de 1.245 participantes, obtidas de banco de dados de três investigações - I Estudo de intervenção (2005-2007), II Estudo caso-controle (2010-2011), III Estudo caso-controle (2012-2015). Resultados: comparando-se os três períodos, as frequências de gengivite (24,41% versus 8,90% versus 5,77%; p<0,01) e periodontite (44,64% vs 9,16% vs 11,55%; p<0,01) diminuíram; relativamente à condição dentária, as piores situações no número de dentes presentes, hígidos, extraídos e índice CPO-D observaram-se no período III, comparativamente ao período II. Conclusão: a condição periodontal melhorou nos anos estudados, coincidentemente com o processo de implantação de políticas de assistência pré-natal, saúde da mulher e saúde bucal, e de redistribuição de renda no município.
Objetivo: evaluar la condición bucal de gestantes y puérperas, usuarias de servicios públicos de salud de la ciudad de Feira de Santana/BA, en tres momentos distintos comprendidos entre 2005 y 2015. Metodos: se trata de un estudio con información sobre características socioeconómicas-demográficas, de condición y cuidado com la salud, de estilo de vida y de condición bucal de 1245 participantes obtenidas en un banco de datos de tres investigaciones previas: I (2005-2007), II (2010-2011), III (2012-2015). Resultados: tanto la frecuencia de gingivitis (24,41% versus 8,90% versus 5,77%; p<0,01) y periodontitis (44,64% vs 9,16% vs 11,55%; p<0,01) disminuyó; em relación a la condición dental, las peores situaciones en cuanto al número de dientes presentes, hígidos, extraídos y el índice CPO-D se observaron en el período III, en comparación con las del período II. Conclusión: se há mejorado la condición periodontal a lo largo de los años, período que coincide com el proceso de implantación de políticas de salud de la mujer, salud bucal, así como redistribución de ingresos en el municipio.
Objective: to evaluate the oral health condition of pregnant/postpartum women attending public services in the city of Feira de Santana, BA, Brazil, at three different times between 2005 and 2015. Methods: this is a study socioeconomic and demographic characteristics, health condition and health care, lifestyle and oral health status of 1,245 participants obtained from a database of three previous investigations: I Intervention Study (2005-2007); II Case-Control Study (2010-2011); III Case-Control Study (2012-2015). Results: comparing the three periods, the frequency of gingivitis (24.41% versus 8.90% versus 5.77%; p<0.01) and periodontitis (44.64% vs 9.16% vs 11.55%; p<0.01) was found to decrease; the worst dental conditions regarding the number of teeth present, healthy and extracted and the DMFT index were found in period III compared to period II. Conclusion: an improvement was seen in the participants' periodontal condition over time, which coincides with the implementation of policies pertaining to women's health, oral health and income redistribution in this city.
Sujet(s)
Humains , Femelle , Grossesse , Hygiène buccodentaire , Prise en charge prénatale , Grossesse , Santé buccodentaire , Femmes enceintes ,RÉSUMÉ
ABSTRACT: Remineralizers are comminuted rocks that are applied to soil, and their use as an agricultural amendment was regulated in Brazil in 2013. However, mechanisms of action of these materials must be better known to enable them to be best used in agricultural fields. Soil chemical attributes of an Oxisol were monitored after the application of a diabase remineralizer. The increase in exchangeable Na observed was associated with the dissolution of the border of the plagioclase crystals where this element is highly concentrated (albite). Therefore, it was inferred that the time since the application of the remineralizer (1 to 2 years depending on the treatment) was not sufficient to exhaust this crystal volume. Unfortunately, the presence of several sources of Ca-containing minerals in the remineralizer did not allow to infer if the calcic nuclei was dissolving. An increase in effective cation exchange capacity was observed without the concurrent increase in the pH of the soil. The two non-exclusive hypotheses proposed to explain this result were that an extra surface charge has originated on the surface of the newly precipitated oxidic phases and/or from the dissolution of the remineralizer grains. Rapid precipitation of amorphous solids (as measured by the increase in Alo and Feo) would also explain the lack of increase in exchangeable Fe and Al despite the large amount of Al2O3 (11.90%) and Fe2O3 (14.45%) in the remineralizer.
RESUMO: O uso de remineralizadores como insumo agrícola foi regularizado em 2013, mas seus mecanismos de ação precisam ser melhor conhecidos para viabilizar o manejo nos campos agrícolas. Atributos químicos de um Latossolo foram monitorados após remineralização com diabásio. O aumento de Na trocável foi atribuído à dissolução das bordas dos plagioclásios (albita) onde a concentração deste elemento é maior. Infelizmente, não é possível especular se o tempo decorrido desde a aplicação (um a dois anos, dependendo do tratamento) foi suficiente para solubilizar o núcleo cálcico (anortita) destes cristais, já que o remineralizador possui outros minerais fonte de Ca. Houve aumento da capacidade de troca catiônica efetiva sem aumento do pH. As hipóteses propostas para explicar este fenômeno são a precipitação de fases oxídicas amorfas e o aparecimento de cargas elétricas na superfície dos grãos do remineralizador durante sua dissolução. Apesar da concentração de Al2O3 do remineralizador (11,90%) e Fe2O3 (14,45%), não houve aumento destes elementos no complexo de troca, possivelmente por sua rápida precipitação em formas amorfas (Alo e Feo no solo).
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Natural stable isotopes, such as carbon (C) and nitrogen (N), are modern tools to assess geochemical processes. C and N in organic matter can carry fingerprints of their hydrologic flows and sedimentary processes, including any anthropogenic modification on the natural system. This study focuses on the determination of aliphatic and polycyclic aromatic hydrocarbons and isotopic ratio in the sediment of Todos os Santos Bay (TSB). The isotopic results of the total organic matter indicate varied contribution marine and terrigenous. Typical rates of PAHs mainly indicate a pyrogenic source and mixture between pyrogenic and petrogenic sources. Typical ratios for the n-alkanes indicate the presence of petroleum hydrocarbons. The isotopic composition of n-alkanes suggests a mixture of sources, with the possible contribution of petrogenic.
Sujet(s)
Hydrocarbures aromatiques polycycliques/analyse , Polluants chimiques de l'eau/analyse , Baies (géographie) , Brésil , Surveillance de l'environnement , Sédiments géologiques , Hydrocarbures aromatiques polycycliques/composition chimique , Polluants chimiques de l'eau/composition chimiqueRÉSUMÉ
A sediment core was taken from the Todos os Santos Bay, near the Mataripe Bahia-Brazil refinery. The results of dating, (210)Pb and (137)Cs methods, combined with organic indicators, Polycyclic aromatic hydrocarbons (PAHs), n-alkanes and total organic carbon (TOC), showed significant change with the start of production of the oil fields of Aratu, Itaparica and Dom João (1939-1947) and the construction of the Mataripe refinery (1949-1950). This event was marked by a series of significant changes, including an abrupt increase in TOC and the growth of PAH concentrations and the presence Unresolved/Resolved ratio (UR/R)>4 in n-alkanes fraction, which indicated that the contamination was of petrogenic origin. The δ(13)C of specific n-alkanes compounds showed gradual deplete with the depth.
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Surveillance de l'environnement , Sédiments géologiques/composition chimique , Polluants chimiques de l'eau/analyse , Alcanes/analyse , Brésil , Hydrocarbures aromatiques polycycliques/analyseRÉSUMÉ
Robust and efficient methylene blue (MB) adsorbent was prepared based on starch/cellulose nanowhiskers hydrogel composite. Maximum MB adsorption capacity of â¼2050mgperg of dried hydrogel was obtained with the composite at 5wt.% of cellulose nanowhiskers and at pH 5. Adsorption capacity varied from 1450mg/g to 2050mg/g with increasing the initial MB concentration from 1500mg/L to 2500mg/L, respectively. For all the concentrations studied ca. 90% of MB was removed by the adsorbent. Optimal conditions were obtained at pH⩾5 due to the generation of negatively charged groups (COO(-)) in the adsorbent, which can strongly interact with the positive charges from MB. The main advantage of this system over other reported adsorbents, besides the fact of being synthesized from biodegradable polymers (starch and cellulose), is its fast adsorption kinetics that follows the pseudo-second order model, which is based on chimisorption phenomenon. Saturation condition was reached as fast as 1h of experiments owing to the formation of an adsorbed MB monolayer as suggested by the Langmuir isotherm model. Desorption experiments showed 60wt.% of MB loaded can be removed from the adsorbent by immersing it in a pH 1 solution, showing its feasibility to be reused. Therefore, starch/cellulose nanowhiskers hydrogel composite presents outstanding capacity to be employed in the remediation of MB contaminated wastewaters.
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Subcutaneous fat necrosis of the newborn is an uncommon, transient and self-healing panniculits. This entity generally follows an uncomplicated course, however there are rare and important complications. The authors present a case of a newborn with subcutaneous fat necrosis complicated by hypercalcemia and nephrocalcinosis. The pathogenesis of hypercalcemia is not fully understood and the nephrocalcinosis can evolve to chronic kidney disease. Clinicians should be aware of subcutaneous fat necrosis as a possible risk factor for hypercalcemia and patients should have serial serum and urinary calcium determinations for up to 6 months after the appearance of the skin lesions. The early diagnosis and prompt treatment of hypercalcemia are essential to prevent severe complications.
A necrose gorda do tecido celular subcutâneo do recém-nascido é uma paniculite rara, transitória e auto-limitada. Tipicamente apresenta evolução favorável, contudo podem surgir complicações potencialmente graves. Apresenta-se um caso que evoluiu com hipercalcémia e nefrocalcinose. A etiopatogenia da hipercalcémia é ainda pouco compreendida e a nefrocalcinose pode constituir uma causa de doença renal crónica. A monitorização regular dos valores de cálcio sérico e urinário neste contexto é essencial, no mínimo até 6 meses após a resolução das lesões cutâneas, porque o diagnóstico precoce e a terapêutica adequada constituem a única possibilidade de prevenir complicações mais graves.