Aseptic Folliculitis in Freshwater and Marine Fishermen

Folliculitis is a common skin disease, usually benign, which causes inflammation and eventual infections of hair follicles. They may have an infectious etiology, mainly due to the bacteria Staphylococcus aureus; it also occurs due to localized irritation, such as in areas of skin friction and for long periods of immersion in water, as in athletes and workers who are continuously exposed to the aquatic environment. Herein, we report on two fishermen, from fluvial and maritime environments, who presented with chronic aseptic folliculitis associated with daily immersion of their lower extremities while exercising the profession and that regressed when there was a decrease in their contact with water.

BackgroundThe silver wattle Acacia dealbata is a fast-growing tree from Australia that has become naturalised in different regions of the world, attaining invasive status in most of them. In Chile, A. dealbata reaches large abundances along banks and floodplains of invaded fluvial systems, suggesting that rivers may act as a vector for seed dispersal. As hydrochory has not been documented previously in this species, the aim of this study is to evaluate the potential for water dispersal of seeds of this invasive tree along rivers.MethodsSeed samples from rivers were collected at three sites along two A. dealbata-invaded rivers within the Cachapoal basin, central Chile. Number of seeds collected was contrasted versus hydraulic and local conditions with RDA. Seed buoyancy and sedimentation velocity were determined and compared between sites with an ANCOVA. Finally, the probability of seed germination after long periods of immersion in water was assessed, simulating transport conditions in the flow. Germination results were tested with a GLM.ResultsResults indicate that increasing abundance of A. dealbata seeds in the flow is related to the level of turbulence of the flow. Seeds display high floatability but their sedimentation velocity is high when they do sink. Finally, silver wattle seeds can germinate after long periods (many weeks) of immersion in water; however, their probability of germination depends to a large extent on whether seeds are scarified or not.ConclusionsBased on the evidence collected, we suggest that the seeds of A. dealbata have the necessary traits to be dispersed by rivers, this being the first research testing this hypothesis. The success of hydrochory of A. dealbata would depend on river flow turbulence, and whether there are natural mechanisms for scarifying the seeds either before or during transport. The proposed methodology can be used to assess river hydrochory for any tree species.

Nanosecond laser interference ablation of fluorine-free aluminum alloy surfaces for dynamic adhesion and static wettability synergistically modulating water collection

The durability of adhesion to phosphoric acid etched, wet dentin substrates

Photosynthetic and physiological responses of Kandelia candel L. Druce seedlings to duration of tidal immersion in artificial seawater

Structural glass fabric/epoxy laminates were exposed to various periods of immersion in water at room and elevated temperatures and tested after oven drying. Changes in weight, dimensions, and mechanical characteristics with exposure indicated that immersion in hot water had a significant effect on residual weight loss and residual tensile strength. A correlation between these two variables could be derived which is independent of hygrothermal history. The observed deterioration of mechanical properties is attributable mainly to degradative processes to which the glass fiber reinforced plastic laminate is subjected as a result of water penetration processes that are accelerated at elevated temperature.

Background:Reflex excitability is increased in hemiplegic patients compared to healthy controls. One challenge of stroke rehabilitation is to decrease the effects of hyperreflexia, which may be possible with water immersion.Methods/Aims:The present study examined the effects of acute water immersion on electrically-evoked Hmax:Mmax ratios (a measure of reflex excitability) in 7 hyperreflexive hemiplegic patients and 7 age-matched healthy people. Hmax:Mmax ratios were measured from soleus on dry land (L1), immediately after (W1) and 5 minutes after immersion (W5), and again after five minutes on land (L5).Results:Water immersion led to an acute increase in Hmax:Mmax ratio in both groups. However, after returning to dry land, there was a non-significant decrease in the Hmax:Mmax ratio of 8% in the hemiplegic group and 10% in healthy controls compared to pre-immersion values.Interpretation:A short period of water immersion can decrease peripheral reflex excitability after returning to dry land in both healthy controls and post-stroke patients, although longer immersion periods may be required for sustainable effects. Water immersion may offer promise as a low-risk, non-invasive and non-pharmaceutical method of decreasing hyperreflexivity, and could thus support aquatic rehabilitation following stroke.

In this study, a high-performance composite was prepared from jute fabrics and polypropylene (PP). In order to improve the compatibility of the polar fibers and the non-polar matrix, alkyl gallates with different hydrophobic groups were enzymatically grafted onto jute fabric by laccase to increase the surface hydrophobicity of the fiber. The grafting products were characterized by FTIR. The results of contact angle and wetting time showed that the hydrophobicity of the jute fabrics was improved after the surface modification. The effect of the enzymatic graft modification on the properties of the jute/PP composites was evaluated. Results showed that after the modification, tensile and dynamic mechanical properties of composites improved, and water absorption and thickness swelling clearly decreased. However, tensile properties drastically decreased after a long period of water immersion. The thermal behavior of the composites was evaluated by TGA/DTG. The fiber-matrix morphology in the modified jute/PP composites was confirmed by SEM analysis of the tensile fractured specimens.

The survival of various faecal bacteria used as indicators of the faecal contamination of water supplies has been investigated in a tropical environment (Sierra Leone). Isolates representing the thermotolerant coliform (TtC) and faecal streptococcus (FS) groups, Clostridium perfringens and Salmonella spp. were studied over a 48 h period of immersion in water from three different sources. Survival patterns varied according to source type, but some general observations were made: a portion of the TtC group was apparently capable of substantial regrowth; FS organisms died off at a faster rate than TtC organisms initially, but survived longer; vegetative cells of C. perfringens died off rapidly; and Salmonella spp. could survive for as long as the other faecal organisms tested. The implications of results for the analysis of tropical waters for faecal contamination are discussed.

The aim of this study is to reduce water uptake of wooden materials manufactured from some tree species. Specimens of 3x3x1.5 cm were prepared from sapwood parts of experimental logs of beech (Fagus orientalis L.Cavr.), alder (Alnus glutinosa Geartn.), spruce (Picea orientalis L.) and scoth pine (Pinus sylvestris L.) wood. The specimens were impregnated by dipping in a solution (3% paraffin wax/10% linseed oil/87% white spirit) at the periods of 1/3, 3 and 24 hours. Then, the specimens were immersed in distilled water for 1/4, 1, 4, 16 and 24 hours. The results were analysed statistically. According to the results, impregnation time, period of immersion in water, and wood species were effective on solution absorption, retention of dry matter, water absorption, and water repellent efectiveness (WRE). The WRE of impregnated specimens were increased with the increase of solution absorption and the retention.Keywords: Wood, Water Absorption, Paraffin, Linseed Oil, Impregnation, Water Repellency.

A surface formed by dense, aligned nickel nanowires (a "nanocarpet") was prepared by electrodeposition through an alumina membrane template, followed by dissolution of the membrane. The nickel nanowires forming the nanocarpet have a very high aspect ratio ( approximately 250), with a diameter of 200 nm and a length of several tens of micrometers. The nickel nanowires are highly rigid, perpendicularly aligned in the nanocarpet with respect to the substrate, and they touch each other at the tips, forming microscale "tepee"-shaped aggregates. By comparison, nanocarpets made of platinum nanowires have a more disordered, wave-like appearance. The nickel nanocarpet, once coated with a hydrophobic surfactant (stearic acid) has superhydrophobic properties (advancing contact angle approximately 158 degrees), and retains its superhydrophobicity after periods of immersion in water, similar to the hydrophobised platinum nanocarpet (advancing contact angle approximately 162 degrees). Interestingly, we observe that simple electrodeposition of platinum also produces pronounced superhydrophobic properties on "flat" copper surfaces. The magnetic properties of nickel might widen the range of applications in which nanocarpets can be gainfully used, such as in surfaces of switchable wettability for microfluidic applications.

Mineral composition, granulometry, cohesion, relative and absolute density, and the pH of samples of the Santa Elena sedimentary rock shoal (37°56′02″ S; 58°11′35″ W; Argentina) were determined in order to relate the endolithic fauna with the properties of the substrate. Twenty three samples were collected in December 1987, applying a systematic sampling method to an intertidal area of 5 500 m2. The mineral composition was determined using x-ray diffraction. Cohesion was determined by visual evaluation of the disintegration of the sample following various periods of immersion in water and by recording the resistance to compressive fracture according to the American Society for Testing and Materials (ASTM) standard. The ASTM standard was also followed for measurement of absolute and relative densities and porosity. The rock was ground up in distilled water and the pH of the resulting liquid measured over a period of 24 h. The data were analysed using numerical taxonomy, and in a supplementary study a granulometric analysis was attempted using five representative samples. The endolithic species selected were: the sipunculanThemiste petricola; the polychaetesPolydora sp. andPherusa sp., and the bivalvesLithophaga patagonica, Petricola patagonica, Saxicava solida, Barnea lamellosa, andPholadidea darwini. The mineral analysis indicated heterogeneous composition and spatial distribution characteristic of a loess. In terms of cohesion, the substrate displayed varying degrees of disintegration, with resistance ranging from zero to very high (254.6 kg/cm2). The endolithic faunaThemiste petricola, Polydora sp.,Pherusa sp.,Lithophaga patagonica, Petricola patagonica, andSaxicava solida were found in areas of low to very high cohesion, with or without calcite. The Pholadidae were found in areas of zero to low cohesion, with absence or traces of calcite. This study indicates the important role of cohesion in determining the distribution of the endolithic fauna.

Este estudo teve como objetivo avaliar estacas de Pinus sp. como isca-armadilha em vários períodos de exposição a cupins subterrâneos em áreas com diferentes composições florísticas no Jardim Botânico do Rio de Janeiro (JBRJ). As iscas-armadilha (previamente embebidas em água destilada por 0, 24 e 48 horas) foram enterradas ao mesmo tempo em três áreas do JBRJ, para retiradas mensais em grupos com exposição de 1 a 12 meses a Coptotermes gestroi (Wasmann) e Heterotermes longiceps (Snyder) (Isoptera: Rhinotermitidae). Houve diferença estatística sobre o tempo de exposição às iscas-armadilha e não houve diferença para um período de imersão em água. Concluiu-se que as iscas-armadilha são naturalmente atraentes para os cupins subterrâneos, e não necessitam de prévia imersão em água destilada para aumentar sua maciez. O tempo de permanência da isca-armadilha no solo não deve exceder a 3 meses para Coptotermes gestroi, em condições de alta luminosidade solar e escassa disponibilidade de matéria orgânica no solo, enquanto que para Heterotermes longiceps, o tempo de exposição pode ser de até 12 meses, em condições de baixa luminosidade e maior disponibilidade de matéria orgânica, fato a ser considerado em programas de controle de cupins. Palavras-chave: Comportamento de cupins; Isoptera; Coptotermes gestroi; Heterotermes longiceps. Abstract Evaluation of Pinus sp. stakes as bait-trap with several periods of exposure to subterranean termites. This study aimed to evaluate stakes of Pinus sp. as bait-trap for several periods of exposure to subterranean termites in areas of different floristic compositions in the Botanical Garden of Rio de Janeiro (JBRJ). Bait-traps were previously immersed in distilled water for 0, 24 or 48 hours. They were buried in three areas of JBRJ for monthly withdrawals in groups with exposure of 1 to 12 months on the species of subterranean termite, Coptotermes gestroi (Wasmann) and Heterotermes longiceps (Snyder). We observed statistical difference on exposure time of the bait-trap,but no difference for the period of immersion in water. We concluded that the bait-trap are naturally attractive to subterranean termites and do not require immersion in distilled water previously in order to increasing their softness. The exposure time of the bait-trap in soil should not exceed 3 months to C. gestroi, under conditions of prolonged effect of sunlight and scarce availability of organic matter, while for H. longiceps the exposure time can be extended to 12 months under conditions of low incidence of sunlight and high availability of organic matter, facts that must be considered on termites control programs.Keywords: Termite's behavior; Isoptera; Coptotermes gestroi; Heterotermes longiceps.

O angico-de-bezerro (Piptadenia moniliformis Benth.) é uma espécie arbórea melífera, de crescimento rápido, característica da caatinga do nordeste brasileiro, onde é muito abundante e com dispersão contígua e irregular. Seus ramos finos, junto com as folhas, servem como alimento para animais. Como suas sementes apresentam dormência por impermeabilidade do tegumento à água, objetivou-se neste trabalho avaliar a eficiência de tratamentos pré-germinativos para superar a dormência de suas sementes visando maximizar e uniformizar o processo de germinação. Foram estudados 28 tratamentos pré-germinativos: imersão em água a 70, 80, 90 ºC e fervente por 1, 2, 3, 4 e 5 minutos e imersão em ácido sulfúrico concentrado por 1, 5, 10, 15, 20, 25 e 30 minutos, além da testemunha. A semeadura foi realizada sobre papel em temperatura alternada de 20-30 ºC, utilizando-se quatro repetições de 25 sementes. Foram avaliadas as porcentagens de germinação das sementes considerando a protrusão da raiz primária, de plântulas normais e de sementes duras e o índice de velocidade de germinação. O delineamento experimental utilizado foi o inteiramente casualizado e as médias comparadas pelo teste de Scott-Knott a 5% de probabilidade. Os tratamentos de imersão em água, independentemente da temperatura e do período de imersão, aumentaram a porcentagem de germinação das sementes, comparativamente ao tratamento controle, mas foram menos eficientes que os tratamentos em ácido sulfúrico nos maiores períodos de imersão. Desta forma, a imersão por 20, 25 e 30 minutos em ácido sulfúrico é recomendada para a superação da dormência de sementes de Piptadenia moniliformis Benth.

Seed coat impermeability to water occurs in many species, including Schizolobium amazonicum Huber ex Ducke. To promote germination in seeds with coat impermeability the use of sulphuric acid (H2SO4) is recommended. The objective of this study was to identify a better time for the scarification with sulphuric acid for S. amazonicum seeds. The effect of scarification with sulphuric acid for 20, 40 and 60 min on germination and speed germination was studied for seeds that were either sowed immediately after scarification or after a 24-hour period of immersion in water. Seeds were sown on a mix of sand and sawdust (1:1). The experimental design was completely randomized with four replications of 50 seeds. The statistical analysis of germination was carried out at six, nine, 12, 15, 18, 21 and 24 days after sowing, in a factorial scheme. For speed germination the means were compared by the Tukey test. There was an interaction between treatments to overcome dormancy and immersion time after scarification in most evaluations. Immersion in water accelerated the beginning of germination. All treatments to overcome dormancy promoted seed germination. However, scarification for 60 min, showed better germination, 92% when immediately sown and 86.5% when sown after 24 hours. Speed germination index was highest for scarified seeds for 60 min followed by immersion in water. Scarification for 60 min was the most efficient treatment to promote germination in S. amazonicum seeds.