Influencia de la expectativa sobre la orientación de la atención

Primeres Jornades de Foment de la Investigació de la FCHS (Any 1995-1996

Effects of the type of exercise performed on the vibration delivered during whole-body vibration exercises

While the internal load factors of whole-body vibration training have been widely investigated, the study of external load magnitude has been overlooked. Thus, the aim of the present study was to evaluate differences in whole-body vibration stimulus magnitude between static/dynamic whole-body vibration training at various vibration conditions. Four Pro 5 Plate vibration platforms were exposed to twelve different vibration conditions and a triaxial USB Impact X250-2 accelerometer was used to measure platform acceleration during each condition. Paired samples t-test was calculated to evaluate differences among amplitude, frequency, time of acceleration and time of deceleration of each platform at each vibration condition and during static (squat of 90° knee flexion) or dynamic exercise (from stand to 90° knee flexion squat). Also, the intra-class correlation coefficients were examined in order to assess the inter-instrument reliability. Peak-to-peak amplitude, frequency, time of acceleration and deceleration of the vibration platform were not modified by the type of exercise performed. Moreover, the four platforms tested showed high repeatability values during the execution of free vibration, static or dynamic squat in all vibration conditions. This study confirms that the vibration delivered by the Pro 5 Plate vibration platform is not modified during the realization of static or dynamic exercises

Histopatología testicular de ratas BIOU: Wistar expuestas a malatión

Objetivo: determinar la histopatología de los testículos de ratas BIOU: Wistar expuestas crónicamente a malatión en comparación con ratas no expuestas. Métodos: estudio experimental con 20 ratas machos asignadas al azar, 10 al grupo control y 10 al expuesto. La exposición consistió en la aplicación crónica de malatión de manera inhalada una vez a la semana durante 2 horas, por 14 semanas; las dosis empleadas fueron equivalentes a las usadas por humanos en agricultura. El grupo control fue expuesto a un placebo (agua destilada) al aire libre por el mismo lapso. Luego, fueron sacrificadas, se obtuvo una muestra sérica para la determinación de la acetilcolinesterasa y se les extrajeron los testículos para el estudio histopatológico. Resultados: los niveles de acetilcolinesterasa fueron significativamente más bajos (p = 0,0001) en el grupo expuesto que en el grupo control. En el estudio histopatológico con microscopia de luz, en el grupo expuesto se evidenció una vacuolización del epitelio germinal en el 50 % de los casos (p = 0,016) para un odds ratio (OR) de 3,00 (95 %: 1,46-6,13), así como espermatogénesis incompleta en el 40 % (p = 0,043) para un OR de 2,66 (95 %: 1,41-5,02); por su parte, no hubo alteraciones en el grupo control. Se observó una correlación inversa significativa (p = 0,0001) entre el número de alteraciones histopatológicas y la actividad de la acetilcolinesterasa. Conclusiones: estos resultados demuestran que la exposición crónica a malatión en ratas BIOU: Wistar puede producir efectos deletéreos en el sistema reproductivo de las ratas

Heart Rate Variability and Exceptional Longevity

Centenarians are the paradigm of human extreme longevity and healthy aging, because they have postponed, if not avoided, mayor age-related diseases. The purpose of this study was to investigate potential differences in resting heart rate variability (HRV) between young adults, octogenarians, and centenarians and assess whether HRV variables are predictors of all-cause mortality in centenarians. To this end, three groups of participants: young adults (N = 20; 20.6 ± 2.3 years), octogenarians (N = 18; 84.1 ± 2.6 years), and centenarians (N = 17; 101.9 ± 1.9 years) were monitored for 15 min at rest (seated, without moving or talking) to measure RR intervals, from which HRV was evaluated. Our results showed a clear decrease with age in the main parasympathetic HRV variables, as well as in the standard deviation (SD) of the RR series [SD of normal-to-normal interval (SDNN)] and in low frequency (LF) heart rate (HR) oscillations, although differences between octogenarians and centenarians did not reach statistical significance. In 14 centenarians followed until death, only SDNN showed significant correlation (¿ = 0.536; p = 0.048) with survival prognosis. Additionally, SDNN <19 ms was associated with early mortality (=1 year) in centenarians (Hazard Ratio = 5.72). In conclusion, HRV indices reflecting parasympathetic outflow as well as SDNN and LF all present an age-related reduction, which could be representative of a natural exhaustion of allostatic systems related to age. Moreover, low SDNN values (<19 ms) could be associated with early mortality in centenarians. HRV seems to play a role in exceptional longevity, which could be accounted for by centenarians’ exposome

Prostatic cyst: An unusual cause of hemospermia

AbstractA 31-year-old man was referred to our service because of recurrent hemospermia over the last 4 years, there were no other symptoms like perineal pain, fever, dysuria, nocturia or urgency; this patient only presented hemospermia with clots. Genital examination was normal. Semen analysis showed no change in volume and pH; however, hemospermia and asthenozoospermia were observed. The semen culture was normal. Ultrasonography only revealed the presence of a cystic lesion adjoining the prostate gland, next to the bladder neck. The retrograde urethrogram was normal. The CT scan revealed only a small calcification in the right seminal vesicle. Endoscopic cistourethroscopy demonstrated 2 cystic dilatations arising on both sides of the prostate gland adjacent to the bladder neck, behind the verumontanum with vessels running over the surface prostatic cyst dilatation. The diagnosis of prostatic gland cystic dilatation was reached and confirmed by pathology that reported fibroconnective tissue with fibrosis and hyalinization. Transurethral unroofing of the cyst was performed separately with a successful outcome

Reproductive strategy of male and female eastern spiny lizards Sceloporus spinosus (Squamata: Phrynosomatidae) from a region of the Chihuahuan Desert, México

We examined the reproductive strategy of male (n = 84) and female (n = 62) S. spinosus from a single population in San Luis Potosí, México. The male reproductive cycle peaked in March and April and declined from May to September, and was not correlated with fat body mass, but was positively correlated with liver mass. The female reproductive cycle peaked in April and May and declined from June through November, and was not correlated with fat body mass, but was correlated with liver mass. Mean clutch size based on oviductal eggs was 17.5 ± 1.9 (n = 12), and was not correlated with female snout-vent length. Our results for S. spinosus are generally similar to those of other populations of the S. spinosus species group. However, there are differences in some traits (e.g., timing of the initiation of the female reproductive cycle; clutch size), suggesting that the S. spinosus group could serve as another model group within Sceloporus to explore ecological and evolutionary causes of among population life history variation

DNA delivery via cationic solid lipid nanoparticles (SLNs)

In recent years the use of solid lipid nanoparticles (SLNs) as transport systems for the delivery of drugs and biomolecules has become particularly important. The use of cationic SLNs developed by the technique of microemulsion, which are complexed with DNA in order to study their application as non-viral vectors in gene therapy, is reported. The nanoparticles are characterized by scanning electron microscopy and transmission electron microscopy (SEM and TEM), atomic force microscopy (AFM) and differential scanning calorimetry (DSC). Furthermore, the process of lyophilization of the samples and their stability was studied. The nanoparticles obtained presented a particle size of 340 nm with a positive surface charge of 44 mV and the capability of forming lipoplexes with DNA plasmids was stated

Effect of polymer structure on gas transport properties of selected aromatic polyimides, polyamides and TR polymers

Thermally rearranged (TR) polymers are formed through a thermally induced solid-state reaction of polyimides or polyamides that contain nucleophilic reactive groups ortho-positioned to their diamine. Naturally, the transport properties of TR polymers are intimately related to the chemical structure and reactivity of their precursors. Herein, we report characterization and transport properties for three poly(hydroxyimide) precursors prepared via thermal imidization in solution and for their corresponding TR polymers. Structural modifications to the polymer backbone can be used to control thermal rearrangement reaction kinetics. In regards to TR polymer formation, samples prepared from diamines with biphenyl functionality reacted more efficiently than those prepared from diamines with hexafluoroisopropylidene-linked aromatic units. However, hexafluoroisopropylidene functional units provided the highest combinations of permeability and selectivity for separations involving H2, N2, O2, CH4, and CO2. Differences in permeability between samples correlated well with changes in free volume, and 3 poly(hydroxyimide)s showed unusually high selectivities for their given free volume. The effect of synthesis route was also investigated for a specific TR polymer derived from 3,3'-dihydroxy-4,4'-diamino-biphenyl (HAB) and 2,2'-bis-(3,4-dicarboxyphenyl) hexafluoropropane dianhydride (6FDA). Poly(hydroxyimide) precursors prepared via thermal imidization in solution and thermal imidization in the solid-state showed nearly identical permeabilities and selectivities regardless of synthesis route. However, after thermal rearrangement, the TR polymers prepared from polyimides synthesized via solid-state imidization have higher gas permeabilities than their solution-imidized analogs. In addition to light gas permeabilities, plasticization effects were investigated with CO2 hysteresis loops for all samples, and pure-gas olefin/paraffin permeabilities were determined for a TR polymer derived from 2,2-bis(3-amino-4-hydroxyphenyl)-hexafluoropropane (APAF) and 6FDA. With the exception of HAB-6FDA polyimides, pure-gas CO2 feed pressures up to approximately 50bar do not reveal a plasticization pressure point, but conditioning effects are observed for most samples. APAF-6FDA TR polymers have pure-gas permeabilities and selectivities beyond the propylene/propane upper bound.The authors gratefully acknowledge the support from Grant DE-FG02-02ER15362,whichwasadministeredbytheU.S.De-partment of Energy(DOE), Division of Chemical Sciences, Geos-ciences, and Biosciences through the Office of Basic Energy Sciences. Additionally, the authors gratefully acknowledge support from the DOEO ffice of Science Graduate Fellowship Program, which managed under DOE contract number DE-AC05-06OR23100 by Oak Ridge Associated Universities (ORAU) and adinistered by the Oak Ridge Institute for Science and Education (ORISE).Peer Reviewe

Alibava : A portable readout system for silicon microstrip sensors

A portable readout system for silicon microstrip sensors is currently being developed. This system uses a front-end readout chip, which was developed for the LHC experiments. The system will be used to investigate the main properties of this type of sensors and their future applications. The system is divided in two parts: a daughter board and a mother board. The first one is a small board which contains two readout chips and has fan-ins and sensor support to interface the sensors. The last one is intended to process the analogue data that comes from the readout chips and from external trigger signals, to control the whole system and to communicate with a PC via USB. The core of this board is a FPGA that controls the readout chips, a 10 bit ADC, an integrated TDC and an USB controller. This board also contains the analogue electronics to process the data that comes from the readout chips. There is also provision for an external trigger input (e.g. scintillator trigger) and a 'synchronised' trigger output for pulsing an external excitation source (e.g. laser system)

Building a Robust, Densely-Sampled Spider Tree of Life for Ecosystem Research

Phylogenetic relatedness is a key diversity measure for the analysis and understanding of how species and communities evolve across time and space. Understanding the nonrandom loss of species with respect to phylogeny is also essential for better-informed conservation decisions. However, several factors are known to influence phylogenetic reconstruction and, ultimately, phylogenetic diversity metrics. In this study, we empirically tested how some of these factors (topological constraint, taxon sampling, genetic markers and calibration) affect phylogenetic resolution and uncertainty. We built a densely sampled, species-level phylogenetic tree for spiders, combining Sanger sequencing of species from local communities of two biogeographical regions (Iberian Peninsula and Macaronesia) with a taxon-rich backbone matrix of Genbank sequences and a topological constraint derived from recent phylogenomic studies. The resulting tree constitutes the most complete spider phylogeny to date, both in terms of terminals and background information, and may serve as a standard reference for the analysis of phylogenetic diversity patterns at the community level. We then used this tree to investigate how partial data affect phylogenetic reconstruction, phylogenetic diversity estimates and their rankings, and, ultimately, the ecological processes inferred for each community. We found that the incorporation of a single slowly evolving marker (28S) to the DNA barcode sequences from local communities, had the highest impact on tree topology, closely followed by the use of a backbone matrix. The increase in missing data resulting from combining partial sequences from local communities only had a moderate impact on the resulting trees, similar to the difference observed when using topological constraints. Our study further revealed substantial differences in both the phylogenetic structure and diversity rankings of the analyzed communities estimated from the different phylogenetic treatments, especially when using non-ultrametric trees (phylograms) instead of time-stamped trees (chronograms). Finally, we provide some recommendations on reconstructing phylogenetic trees to infer phylogenetic diversity within ecological studies