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The activity of two chlorinated isocyanurates (NaDCC and TCCA) and peroxymonosulphate (OXONE) was evaluated against biofilms of Stenotrophomonas maltophilia, an emerging pathogen isolated from drinking water (DW), and for the prevention of biofilm regrowth. After disinfection of pre-formed 48 h-old biofilms, the culturability was reduced up to 7 log, with OXONE, TCCA, and NaDCC showing more efficiency than free chlorine against biofilms formed on stainless steel. The regrowth of biofilms previously exposed to OXONE was reduced by 5 and 4 log CFU cm−2 in comparison to the unexposed biofilms and biofilms exposed to free chlorine, respectively. Rheometry analysis showed that biofilms presented properties of viscoelastic solid materials, regardless of the treatment. OXONE reduced the cohesiveness of the biofilm, given the significant decrease in the complex shear modulus (G*). AFM analysis revealed that biofilms had a fractured appearance and smaller bacterial aggregates dispersed throughout the surface after OXONE exposure than the control sample. In general, OXONE has been demonstrated to be a promising disinfectant to control DW biofilms, with a higher activity than chlorine. The results also show the impact of the biofilm mechanical properties on the efficacy of the disinfectants in biofilm control. [ABSTRACT FROM AUTHOR]

The Cognitive Reserve (CR) describes the brain's ability to actively cope with neurological damage, enabling the maintenance of premorbid cognitive functioning through compensatory processes. The most common way to estimate CR is through formal education, the intelligence quotient (IQ) and participation in cognitive stimulating activities. In the absence of IQ data, the Irregular Word Reading Test (TeLPI) allows you to estimate the premorbid intelligence. The comparison of the TeLPI results between two times of assessment (baseline and re-assessment) with an interval time (IT) of 9 years. To analyze of the stability of their results as a valid dimension for the CR estimation. The TeLPI presented temporal stability of its results between the two evaluation times (IT = 9.07 ± 1.02). The sample, composed by 63 cognitively healthy participants, showed no differences for the estimated Full Scale IQ (t(62) = 0.49, p =.63), for the Estimated Verbal IQ (t(62) = 0.71, p =.48) and for the estimated Performance IQ (t(62) = 0.64, p =.52). Likewise, no differences were found in the number of TeLPI errors at the two assessment times (t(62) = –0.61, p =.54). Considering that CR is characterized as being relatively stable, the TeLPI should be included in its assessment, as an indicator with proved stability over a long period of time, on the physiological aging spectrum. [ABSTRACT FROM AUTHOR]

The effect that the hydrodynamic conditions under which biofilms are formed has on their persistence is still unknown. This study assessed the behaviour of Pseudomonas fluorescens biofilms, formed on stainless steel under different shear stress ( τ w ) conditions (1, 2 and 4 Pa), to chemical (benzalkonium chloride – BAC, glutaraldehyde – GLUT and sodium hypochlorite – SHC) and mechanical (20 Pa) treatments (alone and combined). The biofilms formed under different τ w showed different structural characteristics. Those formed under a higher τ w were invariably more tolerant to chemical and mechanical stresses. SHC was the biocide which caused the highest biofilm killing and removal, followed by BAC. The sequential exposure to biocides and mechanical stress was found to be insufficient for effective biofilm control. A basal layer containing biofilm cells mostly in a viable state remained on the surface of the cylinders, particularly for the 2 and 4 Pa-generated biofilms. [ABSTRACT FROM AUTHOR]

Biodiversity has been degraded all around the world due to anthropogenic factors. To counteract this worldwide tendency, ecological restoration programs are expanding. In these programs, the use of native herbaceous species, particularly those endemic or threatened, can be promoted by seeding them but germination requirements for most of these species are unknown. Our research meant to fill this gap of information for six Iberian endemic species suitable to use in restoration actions - Digitalis thapsi, Ferula communis subsp. catalaunica, Linaria amethystea subsp. amethystea, Pterocephalidium diandrum, Sanguisorba hybrida, and Silene scabriflora subsp. scabriflora. Their seed germination behaviour was analysed to establish germination protocols for conservation actions. Three germination conditions were used to simulate different sown seasons. Seeds of all species were tested without pre-treatment and subjected to a cold stratification. Seeds of S. hybrida and P. diandrum were additionally tested with a scarification treatment. All species reached their better germination performance under autumn conditions (15/10 °C; 8/16 hours). In conclusion, for all the six Iberian endemic species tested, germination speed and percentage were suitable for their use in native plants reinforcement. [ABSTRACT FROM AUTHOR]

The biaxial nematic ( N B ) phase bordered by two uniaxial nematic (discotic – N D and calamitic – N C ) phases and the one between N D phases are studied in potassium laurate (KL), decanol (DeOH) and D 2 O mixture using conoscopic images. The sequences of phases ( N D → N B + → N B − → N C and N D → N B + → N D ) were optically characterized, where N B + and N B − are the biaxial positive and biaxial negative nematic phases, respectively. A new sequence of phases ( N D → N B + → N B − → N B + → N D ) found in one line of the phase diagram positioned close to the interface with the N C phase was also optically confirmed through conoscopic images. The N B + (N B −) → N B − (N B +) transition point was determined by means of image processing. In this review work, we emphasize the relevance of the optical characterization of an N B − phase inherent to the nature of this lyotropic material. [ABSTRACT FROM AUTHOR]

Conoscopic images have confirmed the occurrence of biaxial positive ( N B +) and biaxial negative ( N B − ) nematic phases between the two uniaxial nematic (discotic – N D and calamitic – N C ) phases. Biaxial positive ( N B + ) nematic phase was also optically characterised between two uniaxial N D phases. These nematic phases are found in different phase diagram lines of potassium laurate ( K L), decanol ( D e O H) and deuterium oxide ( D 2 O) lyotropic mixtures. In limited concentration range between the two phase diagram lines the following phase sequence ( N D → N B + → N B − → N B + → N D ) is determined here through conoscopic images. An analysis of the meaning of this result leads us to conclude that the biaxial nematic phase range between uniaxial nematic phases of phase diagrams with nematic lyotropic materials is separated in two regions: one has an optically positive signal and the other, having an optical negative signal. [ABSTRACT FROM AUTHOR]

An intelligent building has to know the specificities of the occupants and determine their drivers to perform actions so that it can optimize the building operation. Five windows of different rooms of the same dwelling were analysed in-depth to understand the specificities and variations of occupants' behaviour. Logistic regressions were used as a machine learning method to predict occupants' actions. The windows opening prediction models were formulated by taking into account continuous and categorical variables. An evaluation of the required data length that allows obtaining the prediction models with results identical to those obtained with the complete year was performed. It was concluded that the best option was to use at least 15 days in summer and 15 days in winter to have a reliable prediction for the full year. The model constructed for each window did not show good prediction success when applied in another room of the same dwelling. This study shows that the specificity of humans needs do not allow a generalization of their behaviours in the built environment. Thus, it is necessary to adapt the algorithms of the building automation systems through data-driven machine learning techniques. [ABSTRACT FROM AUTHOR]

Copyright of Climacteric is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This work aimed to evaluate the action of materials with different copper content (0, 57, 96 and 100%) on biofilm formation and control by chlorination and mechanical stress. Stenotrophomonas maltophilia isolated from drinking water was used as a model microorganism and biofilms were developed in a rotating cylinder reactor using realism-based shear stress conditions. Biofilms were characterized phenotypically and exposed to three control strategies: 10 mg l−1 of free chlorine for 10 min, an increased shear stress (a fluid velocity of 1.5 m s−1 for 30s), and a combination of both treatments. These shock treatments were not effective in biofilm control. The benefits from the use of copper surfaces was found essentially in reducing the numbers of non-damaged cells. Copper materials demonstrated better performance in biofilm prevention than chlorine. In general, copper alloys may have a positive public health impact by reducing the number of non-damaged cells in the water delivered after chlorine exposure. [ABSTRACT FROM AUTHOR]

Refractive index measurements and conoscopic images has confirmed the occurrence of biaxial negative ( N B − ) and biaxial positive ( N B + ) nematic phases between the two uniaxial nematic (calamitic − N C and discotic − N D ) phases. These nematic phases are found in a phase diagram line of potassium laurate (KL), decanol ( D e O H) , potassium sulfate and water. Biaxial positive ( N B +) nematic phase is also optically characterized between two uniaxial N D phases in a KL, DeOH, and D 2 O mixture. Temperature dependence of the angles ( 2 V X and 2 V Z ) between two optic axes of ( N B − and N B + ) phases is obtained from refractive index data. The transition point ( N B − − N B +) characterized by an angle peak corresponds to the change in the biaxial configuration of the optical axes and optical signal of the biaxial nematic phase. The micellar configuration of biaxial nematic phases is discussed as a consequence of our experimental data. [ABSTRACT FROM AUTHOR]

Copyright of Gynecological Endocrinology is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this work we will study the behavior of the optical signal and optical axes along the continuous transition of a lyotropic system from a nematic discotic () phase to a nematic calamitic () phase; we will study in detail the case in which there is a biaxial nematic () phase at the interstice between these two uniaxial phases. It will be shown that the optical signal and optical axes change simultaneously in order to agree with the optical signals of the uniaxial phases at their borders: the optical signal is positive at the frontiers with the phase and it turns to be negative at the frontiers with the phase. Concomitantly, the optical axes rotates from the direction to the direction. We will illustrate these findings with experimental data that confirm our results. [ABSTRACT FROM AUTHOR]

The optical characterization of uniaxial (reentrant discotic - and discotic - ) and biaxial nematic ( phases requires the measurements of two and three refractive indices, respectively. These optical parameters were determined near the reentrant isotropic -isotropic (I) phase transitions in a lyotropic mixture of potassium laurate, decanol and . Biaxial positive ( nematic phase is optically characterized between two uniaxial discotic nematic phases from refractive index data and confirmed via conoscopic images. The micellar configuration of uniaxial and biaxial nematic phases is discussed as a consequence of our experimental data. [ABSTRACT FROM AUTHOR]

In this work, we study and characterize the cholesteric sequence of phases (ChDr−ChB−ChD), where the firstChDris the reentrant cholesteric discotic phase,ChBis the cholesteric biaxial phase and the secondChDis the cholesteric discotic phase. This sequence of phases is studied through polarized light microscopy and image processing technique, where, for the first time, the domains and borders of these transitions are established and characterized. They are also investigated and optically characterized throughout their textures. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the combined effects of streptozotocin-induced diabetes (Di) and ovariectomy in the articular cartilage of rats.Methods: Forty adult female Wistar rats were ovariectomized (OVX) or sham-operated. After recovery from surgery, the animals were assigned randomly into four groups: OVX control (OVX-C); OVX treated with 10 µg/kg/day of 17β-estradiol (OVX-E); sham-operated subjected to Di (Sham-Di); and OVX subjected to Di (OVX-Di). After 60 days of treatment, the animals were euthanized and the distal femurs with articular cartilage were processed for paraffin-embedding. Sections were stained with hematoxylin and eosin for histomorphometry, Picro-Sirius Red for collagen, or Alcian Blue for glycosaminoglycan (GAG) content. To detect apoptosis, sections were stained with an antibody to cleaved caspase-3 (casp-3).Results: Articular cartilage thickness and GAG content were significantly lower (p < 0.05) in the OVX-Di group, which also showed a higher number of casp-3-positive chondrocytes than the other groups. Interestingly, the higher percentage (p < 0.05) of mature collagen fibers was seen in the OVX-Di group, may be as a result of a reduced extracellular matrix remodeling of the articular cartilage.Conclusion: Our results indicate that the combination of ovariectomy and streptozotocin-induced diabetes produces more deleterious effects in articular cartilage of rats than either condition alone. [ABSTRACT FROM AUTHOR]

Objective: To assess the effects of isoflavones and 17β-estradiol on the vaginal epithelium extracellular matrix and hyaluronic acid (HA) in the diabetic rat model.Methods: Sixty adult, virgin, female rats underwent ovariectomy, then randomization into six groups of ten animals each: GI, sham ovariectomized control animals; GII, sham ovariectomized control diabetic animals; GIII, control ovariectomized rats receiving propylene glycol vehicle; GIV, control ovariectomized diabetic animals receiving propylene glycol vehicle; GV, diabetic ovariectomized animals treated with soy isoflavones (150 mg/kg by gavage); GVI, ovariectomized diabetic rats treated with estrogen (17β-estradiol, 10 mg/kg, subcutaneously). Treatment took place over 30 consecutive days. After euthanasia, a portion of the vagina was immersed in liquid nitrogen for RT-qPCR and Western blotting. Another portion was processed for paraffin embedding. Sections were stained with hematoxylin & eosin for histomorphometry and Picro Sirius Red for collagen quantification.Results: Vaginal epithelium histomorphometry in GIII (15.3 ± 1.1 µm) and GIV (14.5 ± 1.8 µm) was thinner than in GV (41.3 ± 1.5 µm) and GVI (74.3 ± 1.6 µm). There was an increase in collagen content in GV (84.1 ± 1.2 µm) and GVI (88.2 ± 1.7 µm). HA quantification was higher in GV (0.38 ± 1.1 μg/mg) and GVI (0.49 ± 1.4 μg/mg) when compared with GIII (0.12 ± 1.1 μg/mg) and GIV (0.10 ± 1.2 μg/mg), p < 0.05.Conclusions: Soy isoflavones increase hyaluronic acid concentration in the vagina of diabetic ovariectomized rats. Such findings might help to attenuate the effects of vulvovaginal atrophy in women. [ABSTRACT FROM AUTHOR]

The indiscriminate use of biocides for general disinfection has contributed to the increased incidence of antimicrobial tolerant microorganisms. This study aims to assess the potential of seven phytochemicals (tyrosol, caffeic acid, ferulic acid, cinnamaldehyde, coumaric acid, cinnamic acid and eugenol) in the control of planktonic and sessile cells ofStaphylococcus aureusandEscherichia coli. Cinnamaldehyde and eugenol showed antimicrobial properties, minimum inhibitory concentrations of 3–5 and 5–12 mM and minimum bactericidal concentrations of 10–12 and 10–14 mM againstS. aureusandE. coli, respectively. Cinnamic acid was able to completely control adhered bacteria with effects comparable to peracetic acid and sodium hypochlorite and it was more effective than hydrogen peroxide (all at 10 mM). This phytochemical caused significant changes in bacterial membrane hydrophilicity. The observed effectiveness of phytochemicals makes them interesting alternatives and/or complementary products to commonly used biocidal products. Cinnamic acid is of particular interest for the control of sessile cells. [ABSTRACT FROM PUBLISHER]

The nematic phases of a lyotropic systemNadS/ decanol/ heavy water are investigated using optical conoscopy and image processing. The phase diagram obtained from these lyotropic materials predicts the occurrence of a direct phase transition, which does not present the biaxial nematic phase, between the discotic (ND) and calamitic (NC) nematic phases. A biaxial nematic (NB) phase is optically characterized and confirmed through conoscopic image, inside the biaxial range, between the two uniaxial nematic phases. Also, their respective transition points are determined by means of image processing. TheNBphase observed here is discussed as part of the nature of the micellar configuration of lyotropic materials which exhibit uniaxial nematic phases. [ABSTRACT FROM AUTHOR]

Introduction: Soy isoflavones have been shown to be an alternative to hormone therapy at menopause, without causing side-effects such as breast cancer. However, the effects of early and late treatment with isoflavones on the mammary gland remain controversial.Objective: To investigate the effects of early and late treatment with soy isoflavones on the mammary gland of ovariectomized rats.Methods: Thirty 3-month-old rats were ovariectomized and divided equally into groups: Control, treated with vehicle solution; or with 150 mg/kg/body weight of isoflavones by gavage; or subcutaneously treated with 10 μg/kg/body weight with 17β-estradiol. Treatments started 3 days (early treatment) or 30 days (late treatment) after ovariectomy and lasted for 30 consecutive days. Thereafter, the animals were euthanized and the mammary glands were removed and processed for paraffin embedding. Sections were stained with hematoxylin and eosin for histomorphometry or subjected to immunohistochemical detection of Ki-67 and VEGF-A.Results: The ductal, lobular and total epithelial fractions were similar between controls and the early/late isoflavone groups, but they were significantly higher in the groups treated with estradiol. In both epithelial and stromal regions, the immunoreactivity of VEGF-A and the percentage of Ki-67-positive cells were significantly higher in the groups treated with estradiol, while they were similar in the early/late isoflavone groups and control groups.Conclusion: Our results indicate that early and late treatment with soy isoflavones at the dose of 150 mg/kg/body weight does not show proliferative and angiogenic effects on the mammary gland of ovariectomized rats. [ABSTRACT FROM AUTHOR]

Objective We evaluated whether genistein or estrogen treatment has the same effect when administered immediately or late to rats induced with menopause using ovariectomy. Methods Sixty adult female rats were divided into six treatment groups: GI = vehicle immediately after ovariectomy; GII = vehicle 30 days after ovariectomy; GIII = genistein immediately after ovariectomy; GIV = genistein 30 days after ovariectomy; GV = estrogen immediately after ovariectomy; and GVI = estrogen 30 days after ovariectomy. All animals were treated for 30 consecutive days. At the end of the treatment, part of the uteri was removed for subsequent histological studies and another part was used to evaluate estrogen receptors 1 and 2, cell proliferation (cyclin A1 and A2, cyclin D1, cyclin-dependent kinase inhibitors 1, 1B and 2, antigen identified by the monoclonal antibody Ki67) and angiogenesis (vascular endothelial growth factor, VEGF-A) gene expression. Results Late treatment after castration in rats resulted in more developed endometrium, enhanced cell proliferation and estrogen-signalling pathways, particularly the cyclin-related genes Ki67 and VEGF-A, compared to early treatment. Interestingly, these same effects were less intense with genistein compared to those induced by estrogen, especially when genistein was administered late. Conclusion Our data show that isoflavone renders a lower risk of cancer when compared to estrogen in treatments. [ABSTRACT FROM AUTHOR]

Objective To evaluate the effects of soy isoflavone extract in the pro-oxidant/antioxidant balance in the uterus of ovariectomized rats. Methods Twenty 3-month-old adult female Wistar rats were divided into four equal groups: GI: sham-operated (estrous phase); GII: control ovariectomized rats; GIII: ovariectomized rats treated with genistein (50 μg/kg/day) by gavage; GIV: ovariectomized rats subcutaneously treated with estrogen (10 μg/kg/day). After 30 consecutive days of treatment, the rats were euthanized and the uterus removed. The distal thirds of the uterine horns were processed for histomorphometric analyses of endometrial and myometrial thicknesses and glandular area. Other regions of the uteri were kept in liquid nitrogen and subsequently processed for analysis of reactive species quantification (DCF), total antioxidant capacity (TAC) and lipid oxidation status (TBARS). Data were statistically analyzed by one-way ANOVA, complemented by the Tukey-Kramer test ( p < 0.05). Results GII and GIII exhibited lower endometrial thickness, glandular area and myometrial thickness than GI and GIV, while a higher myometrial thickness was observed in GIV compared with the other groups. Moreover, the isoflavone-treated group showed lower DCF and TBARS compared to GII, and also an improvement of TAC compared to GI and GIV. Despite the significant decrease in TBARS, no significant difference in DCF nor a decrease in TAC were observed in GIV when compared to GII. Conclusion Our data show that isoflavones improve antioxidant status and counteract oxidative stress, without promoting a trophic effect in the uterus of rats. [ABSTRACT FROM AUTHOR]

Aim Studies report that hormone replacement prevents osteoporosis, but there are doubts whether isoflavones are really efficient in this process. The aim of this study was to evaluate the effects of different doses of soy isoflavones on bone tissue of ovariectomized rats. Methods Forty female rats at the age of 6 months were ovariectomized and, after 3 months, the animals were divided into four groups: GI - Control (treated with drug vehicle); GII - treated with isoflavones (80 mg/kg per day); GIII - treated with isoflavones (200 mg/kg per day) and GIV - treated with isoflavones (350 mg/kg per day). Soy isoflavones were administered by gavage for 90 consecutive days. After treatment, the rats were euthanized and their distal femurs were removed for histological routine, histochemistry and biochemical study. Histological sections were stained with hematoxylin-eosin or subjected to picrosirius red and alcian blue methods. Shafts of femurs were submitted to biochemical assay and tibias were subjected to biophysical and biomechanical tests. Results In distal femurs, the trabecular bone volume was higher in the groups treated with isoflavones, being higher in GIV, while the cortical bone width and the presence of mature type I collagen fibers were higher in GII. At the trabecular bone region, the percentage of total glycosaminoglycans (GAGs) was higher in GII and the percentage of only sulfated GAGs was higher in GIII, while the higher content of chondroitin sulfate in shafts of femurs was seen in GIV. Biophysical and biomechanical tests in tibias did not differ among the groups. Conclusion Our data indicate that soy isoflavones improve bone quality in femurs of rats by increasing histomorphometric parameters, the content of GAGs and mature type I collagen fibers. These positive effects are dose-dependent and it was different in cortical and trabecular bone. [ABSTRACT FROM AUTHOR]

Microtiter plates with 96 wells are routinely used in biofilm research mainly because they enable high-throughput assays. These platforms are used in a variety of conditions ranging from static to dynamic operation using different shaking frequencies and orbital diameters. The main goals of this work were to assess the influence of nutrient concentration and flow conditions on biofilm formation byEscherichia coliin microtiter plates and to define the operational conditions to be used in order to simulate relevant biomedical scenarios. Assays were performed in static mode and in incubators with distinct orbital diameters using different concentrations of glucose, peptone and yeast extract. Computational fluid dynamics (CFD) was used to simulate the flow inside the wells for shaking frequencies ranging from 50 to 200 rpm and orbital diameters from 25 to 100 mm. Higher glucose concentrations enhanced adhesion ofE. coliin the first 24 h, but variation in peptone and yeast extract concentration had no significant impact on biofilm formation. Numerical simulations indicate that 96-well microtiter plates can be used to simulate a variety of biomedical scenarios if the operating conditions are carefully set. [ABSTRACT FROM AUTHOR]

Objective To investigate the effects of soy isoflavones (Iso) and mechanical vibration treatments alone or combined on bone extracellular matrix constituents of ovariectomized rats. Methods Forty female Wistar rats at the age of 6 months were ovariectomized (Ovx) and ten were sham-operated (sham). After 3 months, the animals were divided into five groups: GI (sham); GII (Ovx); GIII, ovariectomized and orally treated with isoflavones (200 mg/kg) for 90 consecutive days; GIV, ovariectomized and submitted to vibration for 90 days (5 days/week); GV, ovariectomized and treated with isoflavones plus vibration. After treatments, the rats were euthanized, and their femurs were removed for histological routine and biochemical study. Histological sections were stained with hematoxylin-eosin, picrosirius red and alcian blue. Shaft of femurs were submitted to biochemical assay and tibias were subjected to biophysical and biomechanical tests. Results Treatments did not have significant effects on the trabecular bone volume, but the combined treatments showed trophic effects on the cortical bone width and area. Bone density and the content of organic material of the tibias were higher in the GIV and GV groups. The GV group showed the highest presence of mature collagen fibers and content of total glycosaminoglycans, while the highest contents of chondroitin sulfate and other sulfated glycosaminoglycans were seen in the GIV group. Conclusion The mechanical vibration treatment is more efficient than soy isoflavones in improving bone quality by increasing the bone density, the content of sulfated glycosaminoglycans and the presence of mature collagen fibers. In addition, the combined interventions have partial trophic and synergistic effects that are bone site-specific in ovariectomized rats. [ABSTRACT FROM AUTHOR]

Here we will show how the use of a geometrical approach leads to a reduction of the number of the viscosity coefficients of the nematic liquid crystals. Usually they are described by five free parameters; we will show that a geometrical approach can reduce this number to three. This result will follow from the modified version of the Hess-Baalss approach. As a consequence of the application of the Onsager relation, these three viscosity terms become related by the effective eccentricity of the nematic grain, leading to a connection between the Miesowicz's coefficients. [ABSTRACT FROM AUTHOR]

In this paper we present an approach that permits to study the behavior of the nematic phase's order parameter exponent (β) for all temperatures of the phase; our method makes an independent calculation ofβfor each temperature valueT. Here use hypothetical data to analyze the consistence of the results, the limitation of the experimental data usability and the influences of the experimental errors on theβ(T) curves. After that, we use experimental data to show that the order parameter critical-like exponent presents a constant behavior along the entire domain of the nematic phase. [ABSTRACT FROM AUTHOR]

In this paper, we synthesize and resume some previous results found on the universality of the nematic phase's anisotropic behavior. Throughout a linear transformation on the experimental data of some anisotropic macroscopic properties, we show that the corresponding points become distributed along universal lines that extend along the entire range of the nematic phase, from the nematic-isotropic phase-transition region until the nematic-crystalline phase-transition region. We also show that the universal curve of the order parameter is characterized by a singular power law behavior, with a single exponent that encompasses the entire range of the nematic phase. [ABSTRACT FROM AUTHOR]

This study presents a new technological approach to minimize the use of antimicrobial (AMB) agents and their deleterious effects, based on the principle of drug-delivery systems whereby the AMB chemicals are transported on microparticles. The efficacy of microparticles carrying the quaternary ammonium compound (QAC), benzyldimethyldodecyl ammonium chloride (BDMDAC), was assessed against Pseudomonas fluorescens in both the planktonic and the biofilm state. The microparticles were prepared using a layer-by-layer (LBL) self-assembly technique. Oppositely charged molecules of polyethyleneimine (PEI), sodium polystyrene sulfonate (PSS), and BDMDAC were assembled on polystyrene (PS) cores. BDMDAC-coated particles were observed by CryoSEM and their composition analyzed by X-ray microanalysis. Zeta potential measurements indicated that changes in surface charge were compatible with a BDMDAC/particle interaction. This biocidal carrier structure had significant stability, verified by the release of only 15% of the BDMDAC when immersed in water for 18 months. Biocidal carrier activity was evaluated by determining the survival ratio of P. fluorescens planktonic and biofilm cells after different exposure periods to BDMDAC-coated particles. Tests with biofilm cells were also performed with the free QAC. An efficient AMB effect (minimum bactericidal concentration) against suspended cells was found for a concentration of 9.2 mg l−1 of BDMDAC on coated particles after incubation for 30 min and 6.5 mg l−1 of BDMDAC on coated particles after 60 min. Exposure of biofilms to PS-PEI/PSS/BDMDAC (0.87 mg l−1) resulted in a decrease in viability of 60.5% and 66.5% of the total biofilm population for 30 and 60 min exposure times, respectively. Exposure for 60 min to 6.33 mg l−1 and 11.75 mg l−1 of BDMDAC in PS-PEI/PSS/BDMDAC particles promoted inactivation of 80.6% and 87.2% of the total population, respectively. The AMB effects obtained with the application of free BDMDAC were statistically similar to those promoted by the application of BDMDAC coated particles. The overall results indicate that this novel AMB strategy has potential for the control of microbial growth of planktonic cells and biofouling. Moreover, the technique allows the reuse of AMB molecules and consequently reduces the environmental risks associated with excessive use of AMB agents, thereby providing real benefits to public health. [ABSTRACT FROM PUBLISHER]

Further studies on Plectranthus sp. (Lamiaceae) led to the isolation of terpenes and phenol esters from Plectranthus strigosus Benth. ent-16-Kauren-19-ol (1), ent-16-kauren-19-oic acid (2), xylopic acid (3), xylopinic acid (4), hinokiol (5), 4β,6β-dihydroxy-1α,5β(H)-guai-9-ene (6) 4β,6β-dihydroxy-1α,5β(H)-guai-10(14)-ene (7), mixtures of hexacosan-1,26-diol and octacosan-1,28-diol ferulate diesters (8), of esters from ferulic acid and fatty alcohols (9) and of esters from fatty acids and 2-(4-hydroxyphenyl)-ethanol (10) were for the first time isolated from this genus. Supplementary spectral data for 3,8 and parvifloron D (11) metabolites are also presented. A bioactivity study revealed herpetic inhibitory properties for (1) and (2), and antioxidant ability for (5) and (8) phenolic constituents. [ABSTRACT FROM AUTHOR]

In this work, experimental birefringence data of several nematic liquid crystals, which share the presence of a nematic-isotropic and a nematic-crystalline phase transition, are used to show that the birefringence presents a universal behaviour which encompasses the entire range of the nematic phase. The meaning and consequences of such behaviour are discussed; as the order parameter is proportional to the birefringence, this result implies that the order parameter has an extended universal profile, similar to a corresponding state law, which is independent of the liquid crystal compound and becomes determined once the temperature interval of the existence of the nematic compounds is obtained. [ABSTRACT FROM AUTHOR]

In this paper the affine connection approach will be used to calculate the elastic constants of nematic liquid crystals. Following this approach, which was originally conceived to compute the nematic viscosity coefficients, an expression for the elastic constants, without adjustable free parameters, will be formulated in terms of a temperature dependent metric, whose non-isotropic part is proportional to the tensorial order parameter of the nematic phase. The dependence of the elastic constants on the scalar order parameter, in the geometry of the nematic molecules, and in the anisotropic part of the molecular interaction, will be determined. [ABSTRACT FROM AUTHOR]

In this work a set of experimental data points is used to study some scaling properties of Miesowicz coefficients. Using the fact that all the compounds studied present two critical points—the crystal–nematic and the nematic–isotropic phase transitions—a common temperature scale was defined. With the use of this unique temperature scale two relevant aspects that distinguish the viscosity of these materials can be simultaneously extracted and studied: (1) the molecular shape anisotropy and (2) the different strengths of molecular interaction of the different compounds. Through the study of the scaling properties associated with these properties, the existence of a common law connecting the Miesowicz coefficients with the associated decay time is proposed. [ABSTRACT FROM AUTHOR]

In this work the critical exponents associated with the behavior of the macroscopic orientational order parameter are determined near the reentrant isotropic (I RE )–discotic nematic (N D ) and N D –isotropic (I) phase transitions in a lyotropic mixture of potassium laurate, decanol and D 2 O by measurement of optical birefringence. The critical exponents found indicate that the low temperature N D –I RE phase transition is quasi-continuous, having a critical exponent, ß 1 ~0.17, which is markedly different from that found at the classical N D –I phase transition, ß 2 ~0.38. The results are discussed and compared with others obtained with different lyotropic mixtures. [ABSTRACT FROM AUTHOR]

This study shows that a short-term respirometric measurement based on the rate of oxygen uptake needed to oxidize glucose is a reliable and fast method to assess biocide efficacy against P. fluorescens cells. Respiratory activity using oxygen consumption rate, the determination of viable and nonviable cells using Live/Dead ® Bac Light™ kit and colony formation units (CFU), were compared as indicators of the biocidal efficacy of ortho-phthalaldehyde (OPA). The results showed that determining the effect of OPA against P. fluorescens using the different methods leads to different conclusions. The minimum bactericidal concentration (MBC) was 80?mg?l -1 , 100?mg?l -1 and 65?mg?l -1 respectively, using respiratory activity, viability using Bac Light counts and culturability. The plate count method was shown to underestimate the biocidal action of OPA, whilst data from respirometry and viability using Live/Dead Bac Light kit correlated strongly and were not statistically different when yellow cells were considered nonviable. Respirometry therefore represents an expeditious, non-destructive and accurate method to determine the antimicrobial action of biocides against aerobic heterotrophic bacteria. [ABSTRACT FROM AUTHOR]

In the present work we study pattern formation in a bi-soft segment urethane/urea elastomer. The material under study is a film prepared from a polypropylene oxide based isocyanate terminated triol prepolymer (PU) and polybutadiene diol (PBDO) with 60% by weight of PBDO. Small angle light scattering (SALS) patterns were recorded as a function of elongation for different rates of extension. It was found that the process of band and stripe formation is dependent upon the sample elongation and rate of extension with a strong increase of band and stripe amplitude with increasing elongation. The SALS data also reveals that the bands' periodicity is independent of the rate of extension within the range studied. [ABSTRACT FROM AUTHOR]