Management of a previously eroded tropical Alfisol with herbaceous legumes: Soil loss and physical properties under mound tillage

A study was carried out on a previously eroded Oxic Paleustalf in Ibadan, southwestern Nigeria to determine the extent of soil degradation under mound tillage with some herbaceous legumes and residue management methods. A series of factorial experiments was carried out on 12 existing runoff plots. The study commenced in 1996 after a 5-year natural fallow. Mound tillage was introduced in 1997 till 1999. The legumes - Vigna unguiculata (cowpea), Mucuna pruriens and Pueraria phaseoloides - were intercropped with maize in 1996 and 1998 while yam was planted alone in 1997 and 1999. This paper covers 1997-1999. At the end of each year, residues were either burned or mulched on respective plots. Soil loss, runoff, variations in mound height, bulk density, soil water retention and sorptivity were measured. Cumulative runoff was similar among interactions of legume and residue management in 1997 (57-151 mm) and 1999 (206-397 mm). However, in 1998, cumulative runoff of 95 mm observed for Mucuna-burned residue was significantly greater than the 46 mm observed for cowpea-burned residue and the 39-51 mm observed for mulched residues of cowpea, Mucuna and Pueraria. Cumulative soil loss of 7.6 Mg ha(-1) observed for Mucuna-burned residue in 1997 was significantly greater than those for Pueraria-mulched (0.9 Mg ha(-1)) and Mucuna-mulched (1.4 Mg ha(-1)) residues whereas in 1999 it was similar to soil loss from cowpea treatments and Pueraria-burned residue (2.3-5.3 Mg ha(-1)). There were no significant differences in soil loss in 1998 (1-3.2 Mg ha(-1)) whereas Mucuna-burned residue had a greater soil loss (28.6 Mg ha(-1)) than mulched cowpea (6.9 Mg ha(-1)) and Pueraria (5.4 Ms ha(-1)). Mound heights (23 cm average) decreased non-linearly with cumulative rainfall. A cumulative rainfall of 500 mm removed 0.3-2.3 cm of soil from mounds in 1997, 3.5-6.9 cm in 1998 and 2.3-4.6 cm in 1999, indicating that (detached but less transported) soil from mounds was far higher than observed soil loss in each year. Soil water retention was improved at potentials ranging from -1 to -1500 kPa by Mucuna-mulched residue compared to the various burned-residue treatments. Also, mound sorptivity at -1 cm water head (14.3 cm h(-1/2)) was higher than furrow sorptivity (8.5 cm h(-1/2)), indicating differences in hydraulic characteristics between mound and furrow. Pueraria-mulched residues for mounds had the highest sorptivity of 17.24 cm h(-1/2), whereas the least value of 6.96 cm h(-1/2) was observed in furrow of Mucuna-burned residue. Pueraria phas eoloides was considered the best option for soil conservation on the previously eroded soil, cultivated with mound tillage. (c) 2005 Elsevier B.V. All rights reserved.

Early intervention for children and their parents following paediatric accidental injury

This study was undertaken to develop and evaluate the efficacy of an early intervention for children who had been injured in an accident. The aim of the intervention was to prevent the development of longterm psychological consequences. Brochures were developed for children, adolescents, and their parents. These brochures detailed common responses to trauma (and normalized such responses), and suggestions for minimizing any post-trauma distress. Participants were children aged 7-15 admitted to hospital for traumatic injury. The intervention was delivered to one of two hospitals, within 72 hours of the trauma. 103 children and parents participated in the study. The parents and children completed structured interviews and questionnaires 2 weeks, 4-6 weeks and 6 months post-trauma. Outcome analyses also indicated that the intervention reduced parental distress at 4-6 weeks post-trauma. The intervention did not impact significantly on child adjustment over this time period. Results of the 6 month follow-up suggested that the intervention resulted in an amelioration of child anxiety from one to six months post-trauma, whereas the controls exhibited an increase in anxiety over this time period. Overall, it was concluded that the early intervention is a simple, practical, and cost-effective method of reducing child and parent distress post-trauma.

Inhibition of iron-catalysed hydroxyl radical formation by inositol polyphosphates: a possible physiological function for myo-inositol hexakisphosphate

1. The ability of myo-inositol polyphosphates to inhibit iron-catalysed hydroxyl radical formation was studied in a hypoxanthine/xanthine oxidase system [Graf, Empson and Eaton (1987) J. Biol. Chem. 262, 11647-11650]. Fe3+ present in the assay reagents supported some radical formation, and a standard assay, with 5 microM Fe3+ added, was used to investigate the specificity of compounds which could inhibit radical generation. 2. InsP6 (phytic acid) was able to inhibit radical formation in this assay completely. In this respect it was similar to the effects of the high affinity Fe3+ chelator Desferral, and dissimilar to the effects of EDTA which, even at high concentrations, still allowed detectable radical formation to take place. 3. The six isomers of InsP5 were purified from an alkaline hydrolysate of InsP6 (four of them as two enantiomeric mixtures) and they were compared with InsP6 in this assay. Ins(1,2,3,4,6)P5 and D/L-Ins(1,2,3,4,5)P5 were similar to InsP6 in that they caused a complete inhibition of iron-catalysed radical formation at > 30 microM. Ins(1,3,4,5,6)P5 and D/L-Ins(1,2,4,5,6)P5, however, were markedly less potent than InsP6, and did not inhibit radical formation completely; even when Ins(1,3,4,5,6)P5 was added up to 600 microM, significant radical formation was still detected. Thus InsP5s lacking 2 or 1/3 phosphates are in this respect qualitatively different from InsP6 and the other InsP5s. 4. scyllo-Inositol hexakisphosphate was also tested, and although it caused a greater inhibition than Ins(1,3,4,5,6)P5, it too still allowed detectable free radical formation even at 600 microM. 5. We conclude that the 1,2,3 (equatorial-axial-equatorial) phosphate grouping in InsP6 has a conformation that uniquely provides a specific interaction with iron to inhibit totally its ability to catalyse hydroxyl radical formation; we suggest that a physiological function of InsP6 might be to act as a 'safe' binding site for iron during its transport through the cytosol or cellular organelles

myo-inositol pentakisphosphates. Structure, biological occurrence and phosphorylation to myo-inositol hexakisphosphate

1. Standard and high-performance anion-exchange-chromatographic techniques have been used to purify myo-[3H]inositol pentakisphosphates from various myo-[3H]inositol-prelabelled cells. Slime mould (Dictyostelium discoideum) contained 8 microM-myo-[3H]inositol 1,3,4,5,6-pentakisphosphate 16 microM-myo-[3H]inositol 1,2,3,4,6-pentakisphosphate and 36 microM-D-myo-[3H]inositol 1,2,4,5,6-pentakisphosphate [calculated intracellular concentrations; Stephens & Irvine (1990) Nature (London) 346 580-583]; germinating mung-bean (Phaseolus aureus) seedlings contained both D- and L-myo-[3H]inositol 1,2,4,5,6-pentakisphosphate (which was characterized by 31P and two-dimensional proton n.m.r.) and D- and/or L-myo-[3H]inositol 1,2,3,4,5-pentakisphosphate; HL60 cells contained myo-[3H]inositol 1,3,4,5,6-pentakisphosphate (in a 500-fold excess over the other species), myo-[3H]inositol 1,2,3,4,6-pentakisphosphate and D- and/or L-myo-[3H]inositol 1,2,4,5,6-pentakisphosphate; and NG-115-401L-C3 cells contained myo-[3H]inositol 1,3,4,5,6-pentakisphosphate (in a 100-fold excess over the other species), D- and/or L-myo-[3H]inositol 1,2,4,5,6-pentakisphosphate, myo-[3H]inositol 1,2,3,4,6-pentakisphosphate and D- and/or L-myo-[3H]inositol 1,2,3,4,5-pentakisphosphate. 2. Multiple soluble ATP-dependent myo-inositol pentakisphosphate kinase activities have been detected in slime mould, rat brain and germinating mung-bean seedling homogenates. In slime-mould cytosolic fractions, the three myo-inositol pentakisphosphates that were present in intact slime moulds could be phosphorylated to myo-[3H]inositol hexakisphosphate: the relative first-order rate constants for these reactions were, in the order listed above, 1:8:31 respectively (with first-order rate constants in the intact cell of 0.1, 0.8 and 3.1 s-1, assuming a cytosolic protein concentration of 50 mg/ml), and the Km values of the activities for their respective inositol phosphate substrates (in the presence of 5 mM-ATP) were 1.6 microM, 3.8 microM and 1.4 microM. At least two forms of myo-inositol pentakisphosphate kinase activity could be resolved from a slime-mould cytosolic fraction by both pharmacological and chromatographic criteria. Rat brain cytosol and a soluble fraction derived from germinating mung-bean seedlings could phosphorylate myo-inositol D/L-1,2,4,5,6-, D/L-1,2,3,4,5-, 1,2,3,4,6- and 1,3,4,5,6-pentakisphosphates to myo-inositol hexakisphosphate: the relative first-order rate constants were 57:27:77:1 respectively for brain cytosol (with first-order rate constants in the intact cell of 0.0041, 0.0019, 0.0056 and 0.000073 s-1 respectively, assuming a cytosolic protein concentration of 50 mg/ml) and 1:11:12:33 respectively for mung-bean cytosol (with first-order rate constants in a supernatant fraction with a protein concentration of 10 mg/ml of 0.0002, 0.0022, 0.0024 and 0.0066 s-1 respectively).

The mechanochemical modification of polyolefins using reactive modifier systems

The principal objective of this work was to improve the mechanical properties of glass fibre reinforced polypropylene (PP) composites by the mechanochemical modification of the PP. The modification of the PP was carried out by reactive processing of the PP with a modifier in a Buss Ko-Kneader. Two main types of modifier were evaluated one type based on N-substituted maleimides the others based on 2-allylamino-4,6-dichloro-1,3,5-triazine (ACCT). The modification of the PP was carried out in two stages. Firstly the PP was reactively processed with the modifier and a free radical initiator. The objective of this stage was to bind the modifier to the PP. In the second stage the modified PP was reactively processed with the glass fibre. The objective in this stage was to form a chemical bond between the bound modifier and the silane coupling agent on the surface of the glass. Two silane coupling agents were evaluated these had a aliphatic chloro group and an aliphatic amino group respectively available for reaction with the modifier. The modifiers synthesised for this work had two main functional groups. The first was a double bond for free radical addition to the PP. The second was an organic group chosen for its potential reactivity to the silane coupling agent. A preliminary investigation was carried out using maleic anhydride (MA) as the modifier, this is reactive to the amino silane coupled glass. Studies of a commercially available system were also carried out for comparison purposes. During the work it was found that the amino silane coupled glass fibres produced, without any modification being made to the PP, mechanical properties comparable to the commercial system. Further any modification added to the amino silane system failed to improve the mechanical performance and in some cases acted in the opposite fashion. This failure was evident even when a chemical bond between glass fibre and PP could be shown. In the case of the chloro silane coupled glass fibres the mechanical properties of the composite without modification were poorer than those of the commercial system. It was found that the mechanical properties of these systems could be enhanced by the modifiers, however, no system tested significantly out performed the commercial system. Of the two modifier systems tested those based on the n-substituted maleimides were more successful at enhancing mechanical properties than those based on ACCT. This was attributed to the Poor chemical binding of the ACCT based modifiers to the PP. During the work it was found that several of the modifiers improved the properties of the PP when no glass fibres were present, particularly the % elongation and impact strength. It is possible that these modifiers could be used to improve the impact performance of PP, this may be of particular interest in recycling. These modifiers have only been tested for improving the properties of glass fibre composites. The N-substituted maleimide based modifiers could be used as compatibleisers for alloys of PP and other polymers. These could function by the formation of the bond with PP via the double bond whilst the group attached to the nitrogen atom could react with the alloying polymer.

Preliminary identification of dehalogenation specificities exhibited by dehalorespiring bacteria from a marine microbial community

The ability of a previously PCB-enriched microbial culture from Venice Lagoon marine sediments to dechlorinate pentachlorophenol (PCP) and 2,3,5-trichlorophenol (2,3,5-TCP) was confirmed under anaerobic conditions in microcosms consisting of site water and sediment. Dechlorination activities against Aroclor 1254 PCB mixture were also confirmed as control. Pentachlorophenol was degraded to 2,4,6-TCP (75.92±0.85 mol%), 3,5-DCP (6.40±0.75 mol%), and phenol (15.40±0.87 mol%). From the distribution of the different dechlorination products accumulated in the PCP-spiked cultures over time, two dechlorination pathways for PCP were proposed: (i) PCP to 2,3,4,6-TeCP, then to 2,4,6-TCP through the removal of both meta double-flanked chlorine substituents (main pathway); (ii) alternately, PCP to 2,3,5,6-TeCP, 2,3,5-TCP, 3,5-DCP, then phenol, through the removal of the para double-flanked chlorine, followed by ortho single-flanked chlorines, and finally meta unflanked chlorines (minor pathway). Removal of meta double-flanked chlorines is thus preferred over all other substituents. 2,3,5-TCP, that completely lacks double-flanked chlorines, was degraded to 3,5-DCP through removal of the ortho single-flanked chlorine, with a 99.6% reduction in initial concentration of 2,3,5-TCP by week 14. 16S rRNA PCR-DGGE using Chloroflexi-specific primers revealed a different role of the two microorganisms VLD-1 and VLD-2, previously identified as dechlorinators in the Aroclor 1254 PCB-enriched community, in the dehalogenation of chlorophenols. VLD-1 was observed both in PCP- and TCP-dechlorinating communities, whereas VLD-2 only in TCP-dechlorinating communities. This indicates that VLD-1 and VLD-2 may both dechlorinate ortho single-flanked chlorines, but only VLD-1 is able to remove double-flanked meta or para chlorines.

Collection of aboveground community and species-specific plant biomass from the Jena Experiment (time series since 2002).

This data set comprises time series of aboveground community plant biomass (Sown plant community, Weed plant community, Dead plant material, and Unidentified plant material; all measured in biomass as dry weight) and species-specific biomass from the sown species of several experiments at the field site of a large grassland biodiversity experiment (the Jena Experiment; see further details below). Aboveground community biomass was normally harvested twice a year just prior to mowing (during peak standing biomass twice a year, generally in May and August; in 2002 only once in September) on all experimental plots in the Jena Experiment. This was done by clipping the vegetation at 3 cm above ground in up to four rectangles of 0.2 x 0.5 m per large plot. The location of these rectangles was assigned by random selection of new coordinates every year within the core area of the plots. The positions of the rectangles within plots were identical for all plots. The harvested biomass was sorted into categories: individual species for the sown plant species, weed plant species (species not sown at the particular plot), detached dead plant material (i.e., dead plant material in the data file), and remaining plant material that could not be assigned to any category (i.e., unidentified plant material in the data file). All biomass was dried to constant weight (70°C, >= 48 h) and weighed. Sown plant community biomass was calculated as the sum of the biomass of the individual sown species. The data for individual samples and the mean over samples for the biomass measures on the community level are given. Overall, analyses of the community biomass data have identified species richness as well as functional group composition as important drivers of a positive biodiversity-productivity relationship. The following series of datasets are contained in this collection: 1. Plant biomass form the Main Experiment: In the Main Experiment, 82 grassland plots of 20 x 20 m were established from a pool of 60 species belonging to four functional groups (grasses, legumes, tall and small herbs). In May 2002, varying numbers of plant species from this species pool were sown into the plots to create a gradient of plant species richness (1, 2, 4, 8, 16 and 60 species) and functional richness (1, 2, 3, 4 functional groups). 2. Plant biomass from the Dominance Experiment: In the Dominance Experiment, 206 grassland plots of 3.5 x 3.5 m were established from a pool of 9 species that can be dominant in semi-natural grassland communities of the study region. In May 2002, varying numbers of plant species from this species pool were sown into the plots to create a gradient of plant species richness (1, 2, 3, 4, 6, and 9 species). 3. Plant biomass from the monoculture plots: In the monoculture plots the sown plant community contains only a single species per plot and this species is a different one for each plot. Which species has been sown in which plot is stated in the plot information table for monocultures (see further details below). The monoculture plots of 3.5 x 3.5 m were established for all of the 60 plant species of the Jena Experiment species pool with two replicates per species like the other experiments in May 2002. All plots were maintained by bi-annual weeding and mowing.

Aboveground community and species-specific plant biomass from the Jena Experiment (Dominance Experiment, year 2008)

This data set contains aboveground community plant biomass (Sown plant community, Weed plant community, Dead plant material, and Unidentified plant material; all measured in biomass as dry weight) and species-specific biomass from the sown species of the dominance experiment plots of a large grassland biodiversity experiment (the Jena Experiment; see further details below). In the dominance experiment, 206 grassland plots of 3.5 x 3.5 m were established from a pool of 9 plant species that can be dominant in semi-natural grassland communities of the study region. In May 2002, varying numbers of plant species from this species pool were sown into the plots to create a gradient of plant species richness (1, 2, 3, 4, 6, and 9 species). Plots were maintained by bi-annual weeding and mowing. Aboveground community biomass was harvested twice in May and August 2008 on all experimental plots of the dominance experiment. This was done by clipping the vegetation at 3 cm above ground in two rectangles of 0.2 x 0.5 m per experimental plot. The location of these rectangles was assigned by random selection of coordinates within the central area of the plots (excluding an outer edge of 50cm). The positions of the rectangles within plots were identical for all plots. The harvested biomass was sorted into categories: individual species for the sown plant species, weed plant species (species not sown at the particular plot), detached dead plant material, and remaining plant material that could not be assigned to any category. All biomass was dried to constant weight (70°C, >= 48 h) and weighed. Sown plant community biomass was calculated as the sum of the biomass of the individual sown species. The mean of both samples per plot and the individual measurements are provided in the data file. Overall, analyses of the community biomass data have identified species richness and the presence of particular species as an important driver of a positive biodiversity-productivity relationship.

Ontogenia del sistema digestivo y caracterización de la actividad enzimática de las larvas de chita Anisotremus scapularis (Tschudi, 1846)

La chita Anisotremus scapularis es un pez marino que habita las costas de Perú, es muy valorado para el consumo humano directo, y, es considerada una especie con potencial acuícola. El cultivo larval en muchas especies de peces marinos se considera como uno de los cuellos de botella para el desarrollo de la tecnología de cultivo a escala comercial, este es el caso de la chita. Como primer alimento y durante los primeros días de vida de las larvas se les suministra presas vivas, y posteriormente, cuando poseen un sistema digestivo más desarrollado, se les suministra alimento balanceado. Sin embargo, los alimentos vivos más empleados no satisfacen los requerimientos nutricionales de las larvas convirtiéndose en un punto crítico. Es por ello, que en los últimos años diversas investigaciones han concentrado sus esfuerzos en la sustitución del alimento vivo por alimento balanceado; no obstante, esto exige un buen conocimiento de la organización y funcionalidad del sistema digestivo. En este sentido, en el presente trabajo se investigan algunos aspectos de la fisiología nutricional de las larvas de chita durante los primeros 30 días de vida. Las larvas fueron cultivadas a partir de huevos obtenidos de desoves naturales de un lote de reproductores mantenidos en cautiverio en el Laboratorio de Cultivo de Peces del Instituto del Mar del Perú (IMARPE). El estudio del crecimiento en longitud, los análisis histológicos y la caracterización enzimática se realizaron a partir de muestras de larvas colectadas a los 0, 1, 2, 3, 4, 6, 8, 10, 14, 18, 22, 26 y 30 días después de la eclosión (DDE). Para los análisis histológicos, las larvas fueron sometidas a un proceso de deshidratación e inclusión en parafina, y teñidos utilizando la técnica de hematoxilina-eosina. La cuantificación de las enzimas digestivas de la chita, proteasas totales (ácidas y alcalinas), tripsina, leucina aminopeptidasa, lipasas dependientes de sales biliares y alfa-amilasa se llevó a cabo con técnicas espectrofotométricas. Al momento de la eclosión, las larvas poseen un tubo digestivo recto e histológicamente indiferenciado ubicado dorsalmente con respecto al saco vitelino, que se caracteriza por poseer una gota de aceite. Entre los 2 y 4 DDE, se observaron los mayores cambios en el desarrollo del sistema digestivo, entre los más importantes están la diferenciación de la bucofaringe, esófago e intestino, plegamiento de la mucosa intestinal, la formación de las microvellosidades en los enterocitos y el desarrollo de sus glándulas anexas, hígado y páncreas, los cuales permitieron la ingestión, digestión y absorción de los primeros alimentos exógenos ingeridos por las larvas. El mayor cambio que se observó en días posteriores fue la observación de un estómago en desarrollo, con la diferenciación de las glándulas gástricas (26 DDE). Las enzimas digestivas analizadas, fueron detectadas desde el momento de la eclosión de las larvas, antes de la apertura de la boca, y se incrementaron con la edad de los organismos. En general, se observó incrementos en la actividad total de las enzimas digestivas a partir de los 8 y 10 DDE o a los 4 mm de longitud total (LT), particularmente con aumentos más marcados en la actividad de las lipasas y de la leucina aminopeptidasa. Para la actividad de proteasas alcalinas totales, tripsina y alfa-amilasa, los aumentos fueron evidentes a partir de los 22 DDE o entre 6 y 7 mm de LT. La actividad de las proteasas ácidas se evidenció e incrementó a partir del 26 DDE o a los 9 mm de LT. En cuanto los patrones de actividad específica, en general, se observaron incrementos súbitos de la actividad que se relacionan con los periodos de transición de la alimentación endógena a exógena (3-6 DDE), y con el cambio de alimentación de rotíferos a metanauplios de Artemia (26 DDE). También, exceptuando la actividad de la leucina aminopeptidasa, se observaron estos incrementos súbitos antes de la primera alimentación. Con base al análisis histológico y bioquímico de las larvas de chita, se recomienda iniciar el destete a los 26 DDE.

The importance of patient involvement in stroke rehabilitation

OBJECTIVE: To investigate the perceived needs for health services by persons with stroke within the first year after rehabilitation, and associations between perceived impact of stroke, involvement in decisions regarding care/treatment, and having health services needs met. METHOD: Data was collected, through a mail survey, from patients with stroke who were admitted to a university hospital in 2012 and had received rehabilitation after discharge from the stroke unit. The rehabilitation lasted an average of 2 to 4.6 months. The Stroke Survivor Needs Survey Questionnaire was used to assess the participants' perceptions of involvement in decisions on care or treatment and needs for health services in 11 problem areas: mobility, falls, incontinence, pain, fatigue, emotion, concentration, memory, speaking, reading, and sight. The perceived impact of stroke in eight areas was assessed using the Stroke Impact Scale (SIS) 3.0. Eleven logistic regression models were created to explore associations between having health services needs met in each problem area respectively (dependent variable) and the independent variables. In all models the independent variables were: age, sex, SIS domain corresponding to the dependent variable, or stroke severity in cases when no corresponding SIS domain was identified, and involvement in decisions on care and treatment. RESULTS: The 63 participants who returned the questionnaires had a mean age of 72 years, 33 were male and 30 were female. Eighty percent had suffered a mild stroke. The number of participants who reported problems varied between 51 (80%, mobility) and 24 (38%, sight). Involvement in decisions on care and treatment was found to be associated with having health services needs met in six problem areas: falls, fatigue, emotion, memory, speaking, and reading. CONCLUSIONS: The results highlight the importance of involving patients in making decisions on stroke rehabilitation, as it appears to be associated with meeting their health services needs.

Editoriale. Luglio 2016: onore alle vittime del terrore a Dacca e a Nizza

Esprimere cordoglio e partecipazione per le vittime delle stragi di Dacca e di Nizza è un dovere di tutti, però da parte di coloro che si interessano di vittimologia si sente la necessità di svolgere qualche considerazione sul tema delle vittime del terrorismo, per ricordarle in modo più significativo.

Estructura de elevador automatizado

Nuestro proyecto trata de un elevador de cuatro pisos que funciona por dos motores de pasos para subir y bajar y abrir y cerrar la puerta de este. Fue realizado principalmente con el propósito de ayudar a las personas con discapacidades visuales o motrices al momento de seleccionar el piso al que se requiere llegar. Además cuenta con botones en caso de que llegue a fallar el sistema de reconocimiento de voz el cual será. Es controlado por un PIC 16F887 que manda las ordenes a dos motores paso a paso, uno que se encarga de hacer subir y bajar el vagón y el otro usado para ejecutar la apertura y cierre de la puerta. Su estructura es de forma cilíndrica para salir un poco de la estructura rectangular habitual que se tiene de los elevadores, y sus paredes son transparentes para una mejor visualización del funcionamiento. Un ascensor o elevador es un sistema de transporte vertical diseñado para movilizar personas o bienes entre diferentes niveles. Puede ser utilizado ya sea para ascender o descender en un edificio o una construcción subterránea. Se conforma con partes mecánicas, eléctricas y electrónicas que funcionan conjuntamente para lograr un medio seguro de movilidad.

Unmasking of the trigemino-accessory reflex in accessory facial anastomosis

To evaluate the possible blink reflex responses in facial muscles reinnervated by the accessory nerve. Method: Eleven patients with a complete facial palsy were submitted to a surgical repair by an accessory facial nerve anastomosis (AFA). In this pathological group, blink reflex was studied by means of percutaneous electrical stimulation of the supraorbital nerve and recording from the orbicularis oculi muscle. A control group comprised seven normal people and seven patients with a complete Bell's facial palsy; in this group, responses on the sternocleidomastoideus (SCM) muscles were studied after supraorbital nerve stimulation. Results: All the patients with AFA showed a consistent degree of facial reinnervation. Ten out of the 11 patients with AFA showed reflex responses; in six, responses were configured by a double component pattern, resembling the R1 and R2 components of the blink reflex; three patients had an R1-like response and one patient showed a unique R2 component. Mean values of latencies were 15.2 (SD 4.6) ms for the R1 and 85.3 (SD 9.6) ms for the R2. In the control group, eight out of 14 people had evidence of reflex responses in the SCM muscles; these were almost exclusively configured by a bilateral late component (mean latency 63.5 (SD 15.9) ms) and only one of the subjects showed an early response at 11 ms. Conclusion: The trigemino-accessory reflex response in the pathological group was more complex and of a significantly higher incidence than in the control group. These differences could be tentatively explained by a mechanism of synaptic plasticity induced by the impairment of the efferent portion of the reflex. This could unmask the central linking between the trigeminal and the accessory limbs of the reflex. The findings described could be a demonstration of neurobionomic function in the repairing process of the nervous system.

Synthesis and characterization of Pd(II) and Pt(II) complexes with triazolopyrimidine derivatives: The crystal structure of [Pd2L2Cl4] where L=5,7-dimethyl-1,2,4-triazolo[1,5-a]pyrimidine

The Pd(II) and Pt(II) complexes with triazolopyrimidine C-nucleosides L-1 (5,7-dimethyl-3-(2',3',5'-tri-O-benzoyl-beta-D-ribofuranosyl-s-triazolo)[4,3-a]pyrimidine), L-2 (5,7-dimethyl-3-beta-D-ribofuranosyl-s-triazolo [4,3-a]pyrimidine) and L-3 (5,7-dimethyl[1,5-a]-s-triazolopyrimidine), [Pd(en)(L-1)](NO3)(2), (Pd(bpy)(L-1)](NO3)(2), cis-Pd(L-3)(2)Cl-2, [Pd-2(L-3)(2)Cl-4]center dot H2O, cis-Pd(L-2)(2)Cl-2 and [Pt-3(L-1)(2)Cl-6] were synthesized and characterized by elemental analysis and NMR spectroscopy. The structure of the [Pd-2(L-3)(2)Cl-4]center dot H2O complex was established by Xray crystallography. The two L-3 ligands are found in a head to tail orientation, with a (PdPd)-Pd-... distance of 3.1254(17) angstrom.L-1 coordinates to Pd(II) through N8 and N1 forming polymeric structures. L-2 coordinates to Pd(II) through N8 in acidic solutions (0.1 M HCl) forming complexes of cis-geometry. The Pd(II) coordination to L-2 does not affect the sugar conformation probably due to the high stability of the C-C glycoside bond. (c) 2006 Elsevier B.V. All rights reserved.

A high mobility P-type DPP-thieno[3,2-b]thiophene copolymer for organic thin-film transistors

A copolymer comprising 1,4-diketopyrrolo[3,4-c]pyrrole (DPP) and thieno[3,2-b]thiophene moieties, PDBT-co-TT, shows high hole mobility of up to 0.94 cm2 V-1 s-1 in organic thin-film transistors. The strong intermolecular interactions originated from π-π stacking and donor-acceptor interaction lead to the formation of interconnected polymer networks having an ordered lamellar structure, which have established highly efficient pathways for charge carrier transport.