Sensitive and high laser damage threshold substrates for surface-enhanced Raman scattering based on gold and silver nanoparticles.

Surface-enhanced Raman scattering (SERS) is a sensitive and fast technique for sensing applications such as chemical trace analysis. However, a successful, high-throughput practical implementation necessitates the availability of simple-to-use and economical SERS substrates. In this work, we present a robust, reproducible, flexible and yet cost-effective SERS substrate suited for the sensitive detection of analytes at near-infrared (NIR) excitation wavelengths. The fabrication is based on a simple dropcast deposition of silver or gold nanomaterials on an aluminium foil support, making the design suitable for mass production. The fabricated SERS substrates can withstand very high average Raman laser power of up to 400 mW in the NIR wavelength range while maintaining a linear signal response of the analyte. This enables a combined high signal enhancement potential provided by (i) the field enhancement via the localized surface plasmon resonance introduced by the noble metal nanomaterials and (ii) additional enhancement proportional to an increase of the applicable Raman laser power without causing the thermal decomposition of the analyte. The application of the SERS substrates for the trace detection of melamine and rhodamine 6G is demonstrated, which shows limits of detection smaller than 0.1 ppm and analytical enhancement factors on the order of 104 as compared to bare aluminium foil.

Avaliação de soluções eletrolíticas e vias da administração sobre o teor de umidade das fezes de equinos desidratados experimentalmente / Evaluation of electrolyte solutions and administration routes on the moisture content of feces of experimentally dehydrated horses

A ocorrência de processos fisiopatológicos que cursam com desidratação da ingesta no trato gastrointestinal dos equinos é comum na rotina clínica. Fatores como diminuição da motilidade intestinal e sobrecarga intraluminal de conteúdo desidratado podem levar a compactação em segmentos como estômago, ceco e cólons. Este estudo objetivou realizar a comparação entre soluções eletrolíticas enterais hipotônica (SeHIPO) e isotônica (SeISO) e a solução Ringer com lactato de sódio (RL IV) sobre o teor de umidade das fezes de equinos submetidos a um período de desidratação experimental (PD). Foram utilizados seis equinos adultos, todas fêmeas com idades entre 10 e 15 anos, média de 440 kg de peso corpóreo. O PD constou de 36 horas de jejum hídrico e alimentar associadas a duas administrações intravenosas de furosemida, sendo a primeira imediatamente no início (T-36) e a segunda 12 horas após o início do PD. Os tratamentos utilizados foram: SeHIPO e SeISO, ambas administradas por via nasogástrica em fluxo contínuo (HETfc), e RL IV administrada pela via intravenosa. Todos os tratamentos foram administrados a uma taxa de infusão contínua de 15mL kg-1 h-1 durante 8 horas consecutivas. O delineamento experimental utilizado foi o crossover6x3, onde cada animal foi submetido, em sistema de rodízio, aos três tratamentos em momentos distintos. As soluções eletrolíticas enterais demonstraram maior eficácia na recomposição do teor de umidade das fezes quando comparadas à terapia RL IV. A hidratação enteral com soluções isotônicas e hipotônicas administrada em fluxo contínuo são eficazes em restaurar o teor de umidade das fezes, podendo ofertar uma opção econômica, segura e eficiente na reidratação de pacientes e nas afecções que cursam como obstruções intraluminais simples.

The occurrence of pathophysiological processes that curse with digesta dryness in the gastrointestinal tract of horses is common in clinical routine, factors such as decreased intestinal motility and intraluminal overload of dry content can lead to compaction in segments such as cecum and colon. This study aimed to compare a hypotonic enteral solution (SeHIPO), an isotonic enteral solution (SeISO) and a Ringer with sodium lactate solution (RL IV) over the moisture content of equine feces submitted to an experimental dehydration protocol. Six adult horses were used, all females aged between 10 and 15 years, average body weight of 440 kg. The PD consisted of a 36 hours period of water and food fasting associated with two intravenous administrations of furosemide, the first immediately at the beginning (T-36) and the second 12 hours after the beginning of the PD. The treatments used were: SeHIPO (hypotonic enteral solution administered via nasogastric), SeISO (enteral isotonic solution administered via nasogastric) and RL IV (Ringer's solution with sodium lactate administered intravenously), all treatments were administered by continuous infusion at a rate of 15mL kg-1 h-1 for 8 consecutive hours. The experimental design used was the 6x3 crossover, where each animal is submitted, in a rotation system, to the three treatments at different times. Enteral fluid therapy with isotonic and hypotonic solutions administered in continuous flow are effective in restoring the moisture content of feces, and may offer an economical, safe, and efficient option for rehydrating patients and in conditions that progress as simple intraluminal obstructions.

A novel green approach based on ZnO nanoparticles and polysaccharides for photocatalytic performance.

Novel green photocatalysts based on ZnO in the presence of arabic gum (AGZ) or karaya gum (KGZ) were synthesized by a sol-gel method for photocatalytic performance. The materials were characterized by XRD, FTIR spectroscopy, SEM, nitrogen adsorption/desorption, and PL and diffuse reflectance spectroscopy. Photocatalytic test was performed using methylene blue (MB) dye as the target pollutant under visible light. The reuse of photocatalysts and Artemia saline bioassays were investigated. The ZnO nanoparticles showed a hexagonal structure and the values of the band gaps were 2.95 (AGZ) and 2.98 eV (KGZ). The PL results demonstrated emission bands at 440, 473 or 478 and 549 nm. The textural properties indicated the presence of typically mesoporous materials. The MB discoloration efficiency was 81.5% and 91.0% for AGZ and KGZ, respectively. The photocatalytic activity of AGZ and KGZ was maintained after the third run. The ˙OH radicals are the main species involved in the MB discoloration. The MB discoloration from the photocatalysts showed no toxicity; therefore, they are considered to be promising materials for the degradation of the dye in the photocatalytic process.

Eco-friendly synthesis and photocatalytic application of flowers-like ZnO structures using Arabic and Karaya Gums.

Flowers-like ZnO structures were synthesized using Arabic Gum (AGZnO) or Karaya Gum (KGZnO). The AGZnO and KGZnO were characterized by X-ray diffractometry, Fourier Transformed Infrared, Scanning Electron Microscopy, Photoluminescence, nitrogen adsorption/desorption and diffuse reflectance techniques. The materials were tested in the discoloration of Methylene Blue (MB) dye under visible light and scavenger studies were also performed. The toxicity of the MB irradiated was investigated in bioassays with Artemia salina. The structural characterization demonstrated the formation of hexagonal ZnO. All samples presented flower-like morphology with presence of mesopores identified by BET method. The optical properties indicated band gap of 2.99 (AGZnO) and 2.76 eV (KGZnO), and emission in violet, blue and green emissions also were observed. The KGZnO demonstrated better photocatalytic performance than the AGZnO, and scavenger studies indicated that OH radicals are the main species involved in the degradation of the pollutant model. The photodiscoloration of MB solution did not demonstrate toxicity. Therefore, KGZnO is a promising material for photocatalysis application.

Avaliação comparativa entre diferentes modalidades de reposição hidroeletrolítica em equinos desidratados experimentalmente pela utilização de parâmetros do exame físico e marcadores hematológicos / Comparative evaluation between different kinds of hydroeletrolitic reposition in horses experimentally dehydrated by the use of physical examination parameters and hematological markers

O objetivo do presente estudo foi realizar a comparação entre três modalidades de terapias hidroeletrolíticas, sendo uma hipotônica (SeHIPO) e outra isotônica (SeISO), ambas por via enteral em fluxo contínuo (HETfc), com a solução de ringer lactato por via intravenosa (RL IV), na taxa de infusão de 15 ml/kg/h, administradas simultaneamente em tempo real por 8 horas num delineamento crossover6X3 em equinos desidratados experimentalmente pela utilização de parâmetros clínicos do exame físico e de alguns exames laboratoriais. Para tanto foram utilizadas 6 éguas adultas da raça Brasileiro de Hipismo submetidas a um protocolo experimental de indução de desidratação (PD) e posteriormente tratadas de acordo com o delineamento experimental. Os resultados obtidos demonstraram que ambos os tratamentos HETfc demonstraram eficácia equivalente ao RL IV na reversão dos efeitos determinados pelo PD, ainda que para os marcadores da volemia, tais como o Volume Globular (VG), Proteínas Plasmáticas Totais (PPT) e porcentagem de Volume Plasmático (%VP) tenham sido relativamente mais lentos. Porém, para os demais marcadores clínicos a eficácia entre as três terapias estudadas foi equivalente. Esses resultados comprovam a ação das terapias HETfc ao serem comparadas ao tratamento RL IV, pela utilização dos marcadores clínicos e laboratoriais utilizados, e justificam a indicação e utilização dessas modalidades terapêuticas em equinos.

The objective of the present study was to compare three modalities of hydroelectrolytic therapies, one hypotonic (SeHIPO) and another isotonic (SeISO), both by continuous enteral flow (HETfc), with intravenous lactated ringer solution ( RL IV), at the infusion rate of 15 ml / kg / h, administered simultaneously in real time for 8 hours in a 6X3 crossover design in horses experimentally dehydrated by the use of clinical parameters of the physical examination and some laboratory tests. Six adult mares of the Brazilian Equestrian race were submitted to an experimental protocol for induction of dehydration (PD) and later treated according to the experimental design. The results showed that both HETfc treatments demonstrated an efficacy equivalent to RL IV in the reversal of the effects determined by PD, although for volume markers such as Globular Volume (VG), Total Plasma Proteins (PPT) and Percentage of Plasmatic Volume (% VP) were relatively slower. However, for the other clinical markers the efficacy among the three therapies studied was equivalent. These results confirm the action of HETfc therapies when compared to RL IV treatment, by the clinical and laboratorial markes used, and justify the indication and use of these therapeutic modalities in horses.

Avaliação comparativa entre diferentes modalidades de reposição hidroeletrolítica em equinos desidratados experimentalmente pela utilização de parâmetros do exame físico e marcadores hematológicos / Comparative evaluation between different kinds of hydroeletrolitic reposition in horses experimentally dehydrated by the use of physical examination parameters and hematological markers

O objetivo do presente estudo foi realizar a comparação entre três modalidades de terapias hidroeletrolíticas, sendo umahipotônica (SeHIPO) e outra isotônica (SeISO), ambas por via enteral em fluxo contínuo (HETfc), com a solução de ringer lactatopor via intravenosa (RL IV), na taxa de infusão de 15 ml/kg/h, administradas simultaneamente em tempo real por 8 horas numdelineamento crossover 6X3 em equinos desidratados experimentalmente pela utilização de parâmetros clínicos do exame físicoe de alguns exames laboratoriais. Para tanto foram utilizadas 6 éguas adultas da raça Brasileiro de Hipismo submetidas a umprotocolo experimental de indução de desidratação (PD) e posteriormente tratadas de acordo com o delineamento experimental.Os resultados obtidos demonstraram que ambos os tratamentos HETfc demonstraram eficácia equivalente ao RL IV na reversãodos efeitos determinados pelo PD, ainda que para os marcadores da volemia, tais como o Volume Globular (VG), ProteínasPlasmáticas Totais (PPT) e porcentagem de Volume Plasmático (%VP) tenham sido relativamente mais lentos. Porém, para osdemais marcadores clínicos a eficácia entre as três terapias estudadas foi equivalente. Esses resultados comprovam a ação dasterapias HETfc ao serem comparadas ao tratamento RL IV, pela utilização dos marcadores clínicos e laboratoriais utilizados, ejustificam a indicação e utilização dessas modalidades terapêuticas em equinos.

The objective of the present study was to compare three modalities of hydroelectrolytic therapies, one hypotonic (SeHIPO) andanother isotonic (SeISO), both by continuous enteral flow (HETfc), with intravenous lactated ringer solution ( RL IV), at the infusionrate of 15 ml / kg / h, administered simultaneously in real time for 8 hours in a 6X3 crossover design in horses experimentallydehydrated by the use of clinical parameters of the physical examination and some laboratory tests. Six adult mares of the BrazilianEquestrian race were submitted to an experimental protocol for induction of dehydration (PD) and later treated according to theexperimental design. The results showed that both HETfc treatments demonstrated an efficacy equivalent to RL IV in the reversalof the effects determined by PD, although for volume markers such as Globular Volume (VG), Total Plasma Proteins (PPT) andPercentage of Plasmatic Volume (% VP) were relatively slower. However, for the other clinical markers the efficacy among thethree therapies studied was equivalent. These results confirm the action of HETfc therapies when compared to RL IV treatment,by the clinical and laboratorial markes used, and justify the indication and use of these therapeutic modalities in horses.

Enzymatic kinetic resolution of internal propargylic diols. Part I: a new approach for the synthesis of (S)-pent-2-yn-1,4-diol, a natural product from Clitocybe catinus.

Internal bis-substituted propargylic diols were subjected to enzymatic kinetic resolution promoted by CAL-B. Employing a two round sequence EKR, mono- and bis-acetoxy propargylic products were obtained in a high enantiomeric ratio (E > 200). The efficiently resolved chiral 8b was applied in a concise synthesis of (S)-1b, an optically active natural product produced by fungi Clitocybe catinus.

Efeito de soluções eletrolíticas enterais com diferentes osmolaridades sobre o perfil eletrolítico e bioquímico de equinos / Horses treated with enteral electrolyte solutions with differents osmolarities

Foram comparados os efeitos de soluções eletrolíticas com diferentes osmolaridades administradas via enteral por sonda nasoesofágica de pequeno calibre, em fluxo contínuo, sobre o perfil bioquímico em equinos. Foram utilizadas seis fêmeas adultas em dois quadrados latinos 6x3 simultâneos em modelo misto. Os animais foram distribuídos em três grupos e cada grupo submetido aos seguintes tratamentos: HipoMalt - 5g de cloreto de sódio, 0,5g de cloreto de potássio, 0,2g de pidolato de magnésio, 1g de gluconato de cálcio e 10g de maltodextrina diluídos em 1.000mL de água (181mOsmol L-1), HipoDext - 5g de cloreto de sódio, 0,5g de cloreto de potássio, 0,2g de pidolato de magnésio, 1g de gluconato de cálcio e 10g de dextrose diluídos em 1.000mL de água (228mOsmol L-1) e IsoProp - 5g de cloreto de sódio, 0,5g de cloreto de potássio, 0,2g de pidolato de magnésio e 10g de propionato de cálcio diluídos em 1.000mL de água (282mOsm L-1). As soluções contendo dextrose (HipoDext) e maltodextrina (HipoMalt) foram mais eficazes em aumentar a taxa glicêmica sem ocasionar desequilíbrio eletrolítico. Já o tratamento com propionato de cálcio (IsoProp) além de aumentar o lactato plasmático não teve efeito sobre a glicemia.

We compared the effects of electrolyte solutions with different osmolarities administered through enteral route by naso-esophageal probe of small-caliber with continuos flow on the electrolytic and biochemical profile in horses. Six adult females were used in two simultaneous 6x3 Latin squares mixed model. The animals were divided into three groups and received the following treatments: HipoMalt - 5g of sodium chloride, 0.5g of potassium chloride, 0.2g of magnesium pidolate, 1g of calcium gluconate and 10g of maltodextrin diluted in 1.000mL of water (181mOsmol L-1); HipoDext - 5g of sodium chloride, 0.5g of potassium chloride, 0.2g of magnesium pidolate, 1g of calcium gluconate and 10g of dextrose diluted in 1.000mL of water (228mOsmol L-1); IsoProp - 5g of sodium chloride, 0.5g of potassium chloride, 0.2g of magnesium pidolate, 1g of calcium gluconate and 10g of calcium propionate diluted in 1.000mL of water (282mOsm L-1). The hypotonic electrolyte solutions containing dextrose (HipoDext) and maltodextrin (HipoMalt) were more effective in increase the rate glucose without causing electrolyte imbalance. Treatment with calcium propionate (IsoProp) besides increasing plasma lactate had no effect on blood glucose.

Soluções eletrolíticas enterais hipotônicas em equinos: efeitos de fontes de energia sobre determinados indicadores do equilíbrio ácido base / Enteral hypotonic electrolyte solutions in horse: effects of energy sources on some indicators of acid - base balance

No presente estudo, foram avaliados os efeitos das soluções eletrolíticas hipotônicas administradas via enteral por sonda nasoesofágica de pequeno calibre em fluxo contínuo sobre o equilíbrio ácido base, lactato plasmático e pH urinário de equinos. Foram utilizadas seis fêmeas equinas adultas, distribuídas aleatoriamente em três grupos, cada um contendo seis animais, em sistema cross over 6x3 (seis animais x três tratamentos). Os animais foram submetidos aos tratamentos: SEDext - 5g de cloreto de sódio, 0,5g de cloreto de potássio, 1g de gluconato de cálcio, 200mg de pidolato de magnésio e 15g de dextrose, diluídos em 1.000mL de água. Osmolaridade mensurada: 264mOsmol/L. SEMalt - solução eletrolítica enteral acrescida de 15g de maltodextrina diluídos em 1.000mL de água. Osmolaridade mensurada 203mOsmol L-1. SESaca - solução eletrolítica enteral acrescida de 15g de sacarose diluídos em 1.000mL de água. Osmolaridade mensurada: 234 mOsmol L-1. As soluções eletrolíticas foram administradas na dose de 15mL kg-1 h-1, durante 12 horas em fluxo contínuo. Os tratamentos com soluções eletrolíticas enterais, associadas à dextrose e maltodextrina, não alteraram os valores da hemogasometria, do ânion gap, da diferença de íons fortes mensurados e do lactato plasmático, enquanto a administração das três soluções ocasionou diminuição nos valores do pH urinário. Apesar disso, elas são clinicamente seguras para ser utilizadas em equinos.

There were analyzed, in the following study, the effects of electrolytic hypotonic solutions that were administrated using small-caliber nasal esophageal probe with continual flow on acid-base balance, plasma lactate and urinary pH of horses . Six adult female were distributed in cross over system 6x3 on a mixed model simultaneously. The animals were distributed in three groups and each of them were managed by the following treatment: SEDext - 5g of sodium chloride, 5g of potassium chloride, 1g of calcium gluconate, 200mg of magnesium pidolate, and 15g of maltodextrin diluted on a 1.000mL of water. The m osmolarity measured was of 264mOsmol L-1. SEMalt - enteral electrolyte solution plus 15g of maltodextrin diluted on a 1.000mL of water. The osmolarity measured was of 203mOsmol L-1. SESucr - enteral electrolyte solution plus 15g of sucrose diluted on a 1,000mL of water. The osmolarity measured was of: 234mOsmol/L. The electrolytic solutions were administered at a dose of 15 ml kg-1 h-1 for 12 hours. Treatments associated with enteral electrolyte solutions associated to dextrose and maltodextrin did not change the average values of blood gas analysis, anion gap, measured strong ion difference and plasma lactate, while the administration of the three solutions caused a decrease in urinary pH values. Nevertheless, they are safe clinically to be used in horses.