Perspex Box Research Articles

Influence of the chest wall on respiratory function at birth in near-term lambs.

Airway liquid is cleared into lung tissue after birth, which becomes edematous and forces the chest wall to expand to accommodate both the cleared liquid and incoming air. This study investigated how changing chest wall mechanics affects respiratory function after birth in near-term lambs with different airway liquid volumes. Surgically instrumented near-term lambs (139 ± 2 days) were randomized into Control (n = 7) or Elevated Liquid (EL; n = 6) groups. Control lambs had lung liquid drained to simulate expected volumes following vaginal delivery. EL lambs had airway liquid drained and 30 mL/kg liquid returned to simulate expected airway liquid volumes after elective cesarean section. Lambs were delivered, transferred to a Perspex box, and ventilated (30 min). Pressure in the box was adjusted to apply positive (7-8 cmH2O above atmospheric pressure) or negative (7-8 cmH2O below atmospheric pressure) pressures for 30 min before pressures were reversed. External negative pressures expanded the chest wall, reduced chest wall compliance (CCW) and increased lung compliance (CL) in Control and EL lambs. External positive pressures compressed the chest wall, increased CCW and reduced CL in Control and EL lambs. External negative pressure improved pulmonary oxygen exchange, reducing the alveolar-arterial difference in oxygen (AaDO2) by 69 mmHg (95% CI [13, 125]; P = 0.016) in Control lambs and by 300 mmHg (95% CI [233, 367]; P < 0.001) in EL lambs. In contrast, external positive pressures impaired pulmonary gas exchange, increasing the AaDO2 by 179 mmHg (95% CI [73, 285]; P = 0.002) in Control and by 215 mmHg (95% CI [89, 343]; P < 0.001) in EL lambs. The application of external thoracic pressures influences respiratory function after birth.NEW & NOTEWORTHY This study investigated how changes in chest wall mechanics influence respiratory function after birth. Our data indicate that the application of continuous external subatmospheric pressure greatly improves respiratory function in near-term lambs with respiratory distress, whereas external positive pressures impair respiratory function. Our findings indicate that, during neonatal resuscitation at birth, the forces applied to the chest wall should not be ignored as they can have a major impact on neonatal respiratory function.

Internal bonding microstructures characterisation between plant nanocellulose and concrete mortar mixtures for indoor Radon-222 gas emanation reduction

• CNF crystallinity index fosters by high frequency ultrasonication. • Great CNF dissemination enhances mechanical strength of the composite brick. • CNF significantly impact internal porosity nanonization of the composite brick. • Tiniest internal porosity observed on 40 mL kenaf CNF composite brick. • Lowest 222 Rn concentration emanated from 40 mL oil palm CNF composite brick. Radon-222 ( 222 Rn) is a natural radioactive gas produced by the radium-226 ( 226 Ra) decay process, which is part of the uranium-238 ( 238 U) decay series. 222 Rn gas can penetrate into the respiratory system during the inhalation process and have an indirect effect on lung tissues due to energetic alpha particles. Brick is a common building material that consists of rock, water, and sand. It is the most prevalent source of 222 Rn gas emanation to humans in an indoor building environment. To reduce indoor 222 Rn gas emanation, kenaf and oil palm cellulose nanofibrils (CNF) were mixed into bricks in certain ratios and acted as liquid fillers. CNFs were produced by using chemical pulping, bleaching, and ultrasonic techniques. Ten composite bricks with different ratios of CNF and one control brick were fabricated by following Malaysia Standard (MS 7.6:1972). The characterization of CNF was done using Fourier Transformed Infrared (FTIR) spectroscopy, X-ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM) and Transmission Electron Microscopy (TEM). The Brunauer-Emmett-Teller (BET) was used to analyse the internal porosity and surface area of the fabricated bricks. 222 Rn concentrations in the bricks and humidity inside the prototype Perspex box were recorded using the Radon Sentinel Monitor Model 1030. The surface areas for control brick, 40 mL kenaf, and oil palm CNF composite bricks are 3.4473 m 2 /g, 4.449 m 2 /g, and 4.9025 m 2 /g, respectively. Meanwhile, pore sizes for control brick, 40 mL kenaf and oil palm CNF composite bricks are 2.92 nm, 0.347 nm and 2.27 nm, respectively. The highest 222 Rn concentration was measured in control brick, which is 3.77 pCi/L, followed by 40 mL kenaf CNF brick and 40 mL oil palm CNF brick, with readings of 1.4 pCi/L and 0.93 pCi/L. The incorporation of CNFs has the ability to reduce 222 Rn emissions while increasing the physical strength of the bricks.

Experimental Investigation of Segregation of Granular Materials using the Vibrational Phenomenon

Many industrial processes including food, mining, material and pharmaceuticals involve the handling of granular materials. Thetendency of granular materials to segregate due to variation of certain parameters as well as differences in particle propertiessuch as size, density, shape negatively affect the process efficiency and product quality. In this study, the segregation phenomenaof different large particles in a granular bed were studied experimentally in a Perspex box that was vibrated vertically. In particular, the effect of frequency, bed depth, particle size and density were investigated. The result showed that the segregationat relatively constant acceleration was found to decrease within the frequency range 20 Hz-40 Hz. On the other hand, thesegregation then increases with increasing frequency. Furthermore, within the same frequency range, segregation was observedto further decrease with increasing acceleration, and then gradually starts decreasing exponentially with frequency. In addition,the segregation rate was higher at a greater bed depth for all vibratory conditions. The segregation trend was found to increasewith the size of the particles for all vibratory conditions. Nonetheless, for all vibratory conditions, the segregation rate was lowerfor intruder particles with higher density

A Phantom Experiment to determine the repeatability of two-dimensional (2D) Pulsed Waved Doppler (PWD) indices using automatic and manual measurement.

Objectives The purpose of this study was to show the repeatability of PWD-derived indices in a wall-less, single-vessel flow phantom experiment, using two different methods of PWD measurement: automatic and manual mode. Methods The phantom was constructed in a Perspex box containing a single channel which was initially created using a silicone tube (5 mm and 6 mm, inner and outer diameter respectively). The tubing was positioned centrally within tissue-mimicking material (TMM) inclined at 45o, then removed once the TMM was set. A 3-roller peristaltic pump was used to circulate blood-mimicking fluid at 45 revolutions/min representing a heart rate (HR) of 135 B.M. 4 acquisitions of 18 cardiac cycles were stored using a GE Voluson E8 with a C1-5-D transducer. Each cardiac cycle was measured individually using automatic and manual mode; 72 waveforms in triplicate for one observer and 18 in triplicate by two experienced observers for intra-observer and inter-observer repeatability, respectively. Measurement differences were assessed by Bland and Altman plots and intra-class correlation coefficients (ICC). Differences between techniques of systolic/diastolic (S/D) ratio, pulsatility index (PI) and resistance index (RI) were analysed by paired t-test. Results Mean S/D, PI, and RI (3.33, 1.02 and 0.70) measured by automatic mode were identical for both observers, whereas by manual mode all indices were significantly different (PI; p = 0.024; p Conclusions Variability within PWD parameters was found depending on the annotation mode used. Using the automatic method lower values, better concordance, less variation and more repeatable results were demonstrated, despite a lack of perfection observed. Interpretation of indices derived from manually annotated waveforms should be interpreted with caution.

An evaluation of correlation and variability of 2D Pulsed Waved Doppler (PWD)-derived indices at varying flow rates: A phantom study

Objectives Previous studies in the literature have demonstrated an inverse relationship between pulsed waved Doppler (PWD) indices and fetal heart rate (FHR). This study aimed to evaluate the correlation between heart rate (HR) with 2D PWD-derived indices in a single vessel flow phantom, aiming to test the impact of HR without physiological in-vivo variability which is known to influence the PWD results. Methods A phantom was constructed using a Perspex box containing a single silicone tube (4.6 mm inner; 5.1 mm outer diameter; 0.5 mm wall thickness) that was positioned centrally and inclined at 45o within tissue-mimicking material. A three-roller peristaltic pump was used to circulate blood-mimicking fluid (BMF). Data were acquired using a GE Voluson E8 with constant machine settings using a 2D linear transducer (C4-8D). The pump was initialized with a flow periodicity of 42 revolutions/min (RPM), which equated to an HR of 126, and the BMF circulated until any air bubbles were expelled. The flow rate (FR) was increased in 1 RPM increments to 58 RPM (HR = 174 bpm). A 10s cine-loop of 2D PWD was acquired in triplicate which equated to approximately 60 cycles for each FR and the waveforms were individually measured using automatic annotation. At each FR, descriptive statistics, regression, correlation and coefficient of variation (CoV) was analysed for each PWD index (systolic/diastolic (S/D) ratio, pulsatility index (PI) and resistance index (RI). Results Across all FR, S/D demonstrated the highest CoV (up to 9.9%), followed by PI (up to 6%) and RI (up to 3.4%). S/D and RI correlated positively with HR (r =0.79 and 0,78, for S/D and RI respectively; p Conclusions Variability within PWD indices was found across all different FR. This phantom study showed a positive correlation between PWD and HR, opposite to findings of studies in the fetus. We believe that the absence of physiological variability in this study may have an impact on the waveforms resulting in the opposite observations. Further studies to assess the relationship between the physiological variability and PWD indices should be encouraged after consideration of the non-physiological variability showed here.

Flies’ halteres sense vertical acceleration

Without the minute auxiliary wings, known as halteres, tucked behind their true wings, airborne flies are going nowhere. William Derham, clergyman and Fellow of the Royal Society, first described how the tiny dumbbell-shaped appendages whirl around over 300 years ago in his book ‘Physico-theology’, adding that insects that had lost the structures fall out of the air ‘manifesting the defect of some very necessary part’. Fast-forwarding to today, we now understand that the halteres detect acceleration and tell flies how their bodies are twisting and turning during flight, but it wasn't clear whether the sensory structures could also sense gravity and alert the insects when they take a tumble.Although flies have a plethora of additional senses that could warn them when they begin to pitch, Kathryn Daltorio and Jessica Fox from Case Western Reserve University, USA, wondered how flies that lack acceleration-sensing halteres would react as they fell. Would they cope as well as intact flies? Constructing a fly-sized fairground ride from a transparent Perspex box, a ball bearing and an electromagnet – to give grey flesh flies the experience of free fall when the electricity was switched off – the duo filmed the insects, first with halteres and then without, as they walked horizontally and vertically, and during a drop, to find out how they would react.Not surprisingly, the flies that had halteres scuttled around at similar speeds regardless of whether they were on the flat or scaling a wall. However, the climbing insects slowed dramatically after the loss of their halteres (from 42 mm s−1 to 20 mm s−1). In addition, when the duo compared the free-falling descents of the flies, it was clear that the insects that had lost their halteres were less well prepared. For example, the flies with halteres sometimes bent their legs, lifted their feet or even took off during the sudden descent. In contrast, the haltere-less flies rarely adjusted their limbs, often clung to the walls of the chamber and were 4.5 times slower unfurling their wings to take off after impact.Wondering why flapping the halteres may be necessary, Daltorio and Fox compared the forces pulling on the gyrating and static sensory organs as the fly tumbled forward. Impressively, the force on the flapping halteres increased by 50% in just 0.0038 s – 20% faster than when the halteres were stationary – which should allow the insects to distinguish quickly between rotating tumbles and vertical falls.Daltorio and Fox say, ‘These calculations show that flies can use halteres to detect vertical accelerations whether they are moving or stationary’, although they admit that the structures are just one of an arsenal of senses upon which the flies can depend when they unexpectedly lose their footing and gravity takes over.

A Plant Based Artefact as a Document of War. Conservation and Preservation of a Wreath made of Yellow Everlasting and Purging Flax, Found on a Warsaw Insurgent’s Grave

Within the collection of the Warsaw Rising Museum there are thousands of historic objects relating to the Warsaw Uprising of 1944. Among ‘typical’ items such as weapons, archival documents and photographs, one can also find unusual souvenirs made of bread, horse hair, animal bones or plant material. One extraordinary item is a wreath found on the Warsaw insurgent’s grave. The wreath was made using yellow everlasting (Helichrysum fulgidum var. nanum or Helichrysum aureum) and purging flax (Linum catharticum) on a frame of steel wire. In 2005 the object was to be exhibited in the Deutsches Historisches Museum (Berlin, Germany) and required conservation assessment. The object required immediate intervention. The wreath was covered with dust and ingrained dirt. The flowers were friable and partially disintegrated. There were some loose fragments of flowers that had detached from the whole construction. The conservation treatment endeavoured to stabilise, consolidate and reinforce the weakened elements. The wreath was dry cleaned with a delicate soft brush. Loose fragments served as samples to test the consolidation materials. Initial tests involved Paraloid B-72, frequently used to reinforce ethnographic plant-based artefacts, applied with brush. During application the solution formed clumps and would leave crystal-like residues. Moreover, the application with a brush turned out to be too invasive for the flower structure and risked disintegrating the plant material. Therefore further tests requiring the use of a brush were ruled out. It also excluded testing consolidants such as methyl cellulose. Given our capacity at that time, it was decided that a consolidant that may be applied as a sprayed solution would be used. At that time our conservation studio was not equipped with an ultrasonic nebuliser. We used another detached flower fragment to test the fixative, commonly used for drawings, pastels and watercolours. The product, available as a spray solution, consists of ketonic resin, castor oil and alcohol. Tests gave satisfying results in the reinforcement of the flower and limited the accumulation of dirt. The fixative was then used to reinforce the whole wreath. The wreath was placed in a purpose designed perspex box that served as both storage box and display case. The wreath was safely transported to Berlin where it was displayed for the next three years. After it was returned to the Warsaw Rising Museum, the condition assessment revealed that there were no changes in the artefact structure. Since then the wreath has been successfully exhibited in the permanent exhibition at the Warsaw Rising Museum.

Hourly and monthly variations in the surface activity patterns of Hemilepistus reaumurii in arid environments of Tunisia

Life in desert ecosystems drives animals to adapt their surface locomotor activity according to environmental conditions. In this study, the hourly and monthly variations in the surface activity patterns of the terrestrial crustacean Hemilepistus reaumurii were investigated. The surface activity of H. reaumurii at the population scale was observed by collecting the hourly active individuals from the sunrise to the sunset of the studied day in each month of 2013 in the Bchachma locality, Tunisia. The collected active individuals were put in perspex boxes (on which we labeled the hourly time interval in which the individuals were collected) in the field and then transported to the laboratory for analysis. Individuals were counted, sexed, and measured in the laboratory. Despite desert conditions in the studied site, H. reaumurii was characterized by a diurnal surface activity, showing a bimodal pattern during the warm months (i.e., May to October). However, it exhibited a unimodal surface activity pattern in the cold months (i.e., February, March, and November). The surface activity was significantly correlated with sunrise and sunset. Moreover, a significant quadratic effect of temperature on the surface activity of H. reaumurii was observed. Furthermore, the study showed that the most important surface activity was recorded in March. The daily exploitation of the temporal niches was significantly different as a function of months. The body size of males was larger than that of females, and the body size of active individuals changed with months. All these behavioural changes in the surface activity represent an adaptive strategy of life in the arid environment.

LDA measurements of coherent flow structures and cross-flow across the gap of a compound channel with two half-rods

The enhancement of heat transfer from fuel rods to coolant of a Liquid Metal Fast Reactor (LMFR) decreases the fuel temperature and, thus, improves the safety margin of the reactor. One of the mechanisms that increases heat transfer consists of large coherent structures that can occur across the gap between adjacent rods. This work investigates the flow between two curved surfaces, representing the gap between two adjacent fuel rods. The aim is to investigate the presence of the aforementioned structures and to provide, as partners in the EU SESAME project, an experimental benchmark for numerical validation to reproduce the thermal hydraulics of Gen-IV LMFRs. The work investigates also the applicability of Fluorinated Ethylene Propylene (FEP) as Refractive Index Matching (RIM) material for optical measurements.The experiments are conducted on two half-rods of 15 mm diameter opposing each other inside a Perspex box with Laser Doppler Anemometry (LDA). Different channel Reynolds numbers between Re = 600 and Re = 30,000 are considered for each P/D (pitch-to-diameter ratio).For high Re, the stream wise velocity root mean square vrms between the two half rods is higher near the walls, similar to common channel flow. As Re decreases, however, an additional central peak in vrms appears at the gap centre, away from the walls. The peak becomes clearer at lower P/D ratios and it also occurs at higher flow rates. Periodical behaviour of the span wise velocity across the gap is revealed by the frequency spectrum and the frequency varies with P/D and decreases with Re. The study of the stream wise velocity component reveals that the structures become longer with decreasing Re. As Re increases, these structures are carried along the flow closer to the gap centre, whereas at low flow rates they are spread over a wider region. This becomes even clearer with smaller gaps.

Investigation of dental alginate and agar impression materials as a brain simulant for ballistic testing

Routine forensic research into in vitro skin/skull/brain ballistic blood backspatter behavior has traditionally used gelatin at a 1:10 Water:Powder (W:P) ratio by volume as a brain simulant. A limitation of gelatin is its high elasticity compared to brain tissue. Therefore this study investigated the use of dental alginate and agar impression materials as a brain simulant for ballistic testing. Fresh deer brain, alginate (W:P ratio 91.5:8.5) and agar (W:P ratio 81:19) specimens (n=10) (11×22×33mm) were placed in transparent Perspex boxes of the same internal dimensions prior to shooting with a 0.22inch caliber high velocity air gun. Quantitative analysis to establish kinetic energy loss, vertical displacement elastic behavior and qualitative analysis to establish elasticity behavior was done via high-speed camera footage (SA5, Photron, Japan) using Photron Fastcam Viewer software (Version 3.5.1, Photron, Japan) and visual observation. Damage mechanisms and behavior were qualitatively established by observation of the materials during and after shooting. The qualitative analysis found that of the two simulant materials tested, agar behaved more like brain in terms of damage and showed similar mechanical response to brain during the passage of the projectile, in terms of energy absorption and vertical velocity displacement. In conclusion agar showed a mechanical and subsequent damage response that was similar to brain compared to alginate.

Quantitative analysis of orthopedic metal artefact reduction in 64-slice computed tomography scans in large head metal-on-metal total hip replacement, a phantom study.

PurposeQuantification of the effect of O-MAR on decreasing metal artefacts caused by large head metal on metal total hip arthroplasty (MoM THA) in a dedicated phantom setup of the hip.BackgroundPathological reactions of the hip capsule on Computed tomography (CT) can be difficult to diagnose due to different metal artefacts. The O-MAR algorithm deploys an iterative loop where the metal sinogram is identified, extracted, and subsequently serves as a mask to correct the measured sinogram. Main goal of this study is to quantify the ability of the O-MAR technique to correct deviation in medullary bone attenuation caused by streak artefacts from the large-head MoM THA embedded in a phantom. Secondary goal is to evaluate the influence of O-MAR on CNR.MethodsThe phantom was designed as a Perspex box (PMMA) containing water and a supplementary MOM THA surrounded by Perspex columns comprising calibrated calcium pellets. Each column contains 200 mg of hydroxyapatite/calcium carbonate to simulate healthy bone tissue. Scans were obtained with and without a MoM THA at different dose levels. Different reconstructions were made with filter A, iDose4 level 5 and with and without O-MAR. The scans without the prosthesis were used as the baseline. Information about the attenuation in Hounsfield units, image noise in standard deviation within the ROI’s were extracted and the CNR was calculated.ResultsPellet L0 and R0 (proximal of the MoM THA) were defined as reference, lacking any disturbance by metal artefacts; L5, L6 and L8 were respectively visually categorized as ‘light’ ‘medium’ and ‘heavy disturbance’. Significant improvements in attenuation deviation caused by metal artefact were 43, 68 and 32 %, for respectively pellet L5, L6 and L8 (p < 0.001). Significant CNR improvements were present for L5 and L6 and were respectively 72 and 52 % (p < 0.001). O-MAR showed no improvement on CNR for L8.ConclusionThis phantom study significantly increases image quality by the use of O-MAR in the presence of metal artefacts by significantly reducing metal artefacts subsequently and increasing CNR on a 64 slice CT system in light and medium disturbance of the image.

Mycorrhizal hyphal disruption induces changes in plant growth, glomalin-related soil protein and soil aggregation of trifoliate orange in a core system

By breaking up soil, tillage often disrupts mycorrhizal extraradical mycelium (ERM). In a core having four windows covered with 37-μm mesh in a perspex box, trifoliate orange (Poncirus trifoliata) seedlings were colonized with an arbuscular mycorrhizal (AM) fungus, Funneliformis mosseae. The core was rotated weekly at 180° around vertical axes, in order to simulate ERM disruption. After 13 such rotations, root mycorrhizal colonization, soil hyphal length inside and outside the core, and plant biomass were substantially reduced. On the other hand, mycorrhizal inoculation without disruption of ERM (static core) was associated with significant increase in biomass production, compared with disruption of ERM (rotating core). Disruption of ERM (rotating core) inhibited the production of easily-extractable glomalin-related soil protein (EE-GRSP) and total GRSP (T-GRSP) inside the core under mycorrhization, due to breakdown of ERM. Mycorrhization markedly increased soil organic carbon content, distribution of water-stable aggregate (WSA) at 0.5–4mm size and mean weight diameter (MWD), whereas core rotation showed a negative effect on MWD and the percentage of WSA within 1–4mm size under mycorrhization and within 0.25–2mm size under non-mycorrhization. It was proposed that soil tillage, in terms of the core rotation, strongly disrupted ERM network, which adversely influenced EE-GRSP and T-GRSP production and plant growth under mycorrhization, subsequently weakening the GRSP functioning on WSA stability.

Field Programmable Gate Array Implementation of Active Control Laws for Multi-mode Vibration Damping

A B S T R A C T This paper investigates the possibility and effectiveness of multi-mode vibration control of a plate through real-time FPGA (Field Programmable Gate Array) implementation. This type of embedded system offers true parallel and high throughput computation abilities. The control object is an aluminum panel, clamped to a Perspex box’s upper side. Two types of control laws are studied. The first belongs to non-model based control. This control law is designed to generate active damping within the designed bandwidth. The second control law is model based H-infinity robust control. A system identification process is needed before the controller comes out. Each of the control laws is implemented on a FPGA target, which is powerful enough to achieve high throughput control loop rates. The experimental control results demonstrate that the non-model based control law has sufficient authority to suppress the interesting modes. The model-based robust control law’s control performance is not so positive compared to the previous method. Therefore, it is not recommended for this application.

Potential of Fabricated Light Foamed Concrete in Reducing Radon from Building Material

Three of Light Foamed Concrete (LFC) have been obtain by using different formula of Cement:Aggregates. The brick was locate into a closed Perspex box and the net of 222Rn concentration level have been measured for 5 consecutive days. The results show the LFC 3 has produced the lowest of net 222Rn concentration level in air, followed by LFC 2 and LFC 1, respectively. The result also show the 222Rn concentration level have been influenced by the temperature and relative humidity in air.

Mechatronics meets biology: experiences and first results with a multipurpose small mammal monitoring unit used in red squirrel habitats

Monitoring is a fundamental aspect of species conservation and research. Technological advances, especially with respect to camera trap technologies, have allowed glimpses into unknown aspects of species behaviour and have the potential to greatly assist species distribution monitoring. Here we present the findings of a pilot study combining existing biological monitoring techniques with mechatronics to advance monitoring technologies and develop a multi-purpose, species specific, automated monitoring system. We developed a Small Mammal Monitoring Unit (SMMU) that integrates automated video, and sound recording, carries out body weight measurements and takes hairs samples with a bait station in a portable perspex box. The unit has the potential for use with a range of small mammal species, but has been field-tested here on red squirrels, Sciurus vulgaris , in Germany, Scotland and Switzerland. We successfully collected hair-samples, body mass data as well as video and sound recordings. Preliminary data analyses also revealed behavioural information. Heavier individuals first gained access to the feeder in the morning and have longer feeding bouts. Our prototype demonstrated that the collaboration between mechatronic and biology offers novel, integrated monitoring techniques for a range of research application. The development of units for other mammal species is planned. Future developments will explore the possibilities for wireless data transmission, built-in collection of weather data and collection of images from inside the unit for the recognition of individuals. Download the complete issue.

Octopus arm movements under constrained conditions: adaptation, modification and plasticity of motor primitives.

The motor control of the eight highly flexible arms of the common octopus (Octopus vulgaris) has been the focus of several recent studies. Our study is the first to manage to introduce a physical constraint to an octopus arm and investigate the adaptability of stereotypical bend propagation in reaching movements and the pseudo-limb articulation during fetching. Subjects (N=6) were placed inside a transparent Perspex box with a hole at the center that allowed the insertion of a single arm. Animals had to reach out through the hole toward a target, to retrieve a food reward and fetch it. All subjects successfully adjusted their movements to the constraint without an adaptation phase. During reaching tasks, the animals showed two movement strategies: stereotypical bend propagation reachings, which were established at the hole of the Perspex box and variant waving-like movements that showed no bend propagations. During fetching movements, no complete pseudo-joint fetching was observed outside the box and subjects pulled their arms through the hole in a pull-in like movement. Our findings show that there is some flexibility in the octopus motor system to adapt to a novel situation. However, at present, it seems that these changes are more an effect of random choices between different alternative motor programs, without showing clear learning effects in the choice between the alternatives. Interestingly, animals were able to adapt the fetching movements to the physical constraint, or as an alternative explanation, they could switch the motor primitive fetching to a different motor primitive 'arm pulling'.

Exacerbation of Brain Pathology After Partial Restraint in Hypertensive Rats Following SiO2 Nanoparticles Exposure at High Ambient Temperature

This investigation examines the possibility that exposure to silica dust of hypertensive individuals may exacerbate brain pathology and sensory motor dysfunction at high environmental temperature. Hypertension was produced in rats (200-250 g) by two-kidney one clip (2K1C) method, and in these animals, SiO2 nanoparticles (NPs; 50 to 60 nm) were administered at 50 mg/kg, i.p. daily for 1 week. On the 8th day, these rats were subjected to partial restraint in a Perspex box for 4 h either at room temperature (21 °C) or at 33 °C in a biological oxygen demand incubator (wind velocity, 2.6 cm/s; relative humidity, 65 to 67 %). In these animals, behavioral functions, blood-brain barrier (BBB) permeability to Evans blue albumin (EBA) and radioiodine (([131]-)Iodine), brain water content and neuronal injuries were determined. Hypertensive rats subjected to 4 h restraint at room temperature did not exhibit BBB dysfunction, brain edema, neural injury, or alterations in rotarod or inclined plane angle performances. However, when these hypertensive rats were subjected to restraint at 33 °C, breakdown of the cortical BBB (EBA, +38 %; radioiodine, +56 %), brain water (+0.88 %), neuronal damages (+18 %), and behavioral impairment were exacerbated. Interestingly, SiO2 exposure to these rats further exacerbated BBB breakdown (EBA, 280 %; radioiodine, 350 %), brain edema (4 %), and neural injury (30 %) after identical restraint depending on the ambient temperature. SiO2 treatment also induced brain pathology and alteration in behavioral functions in normotensive rats after restraint at high temperature. These observations clearly show that hypertension significantly enhances restraint-induced brain pathology, and behavioral anomalies particularly at high ambient temperature and SiO2 intoxication further exacerbated these brain pathologies and cognitive dysfunctions.

Investigation of centreline strain path during tube penetration using transparent soil and particle image velocimetry

A small-scale physical modelling system was developed and employed to investigate the effects of tube sampling. Amorphous silica and an oil blend of matching refractive index were mixed to form a transparent soil, and black glass beads were embedded within the soil body on the vertical central plane. After consolidation in a Perspex box, round-tipped thick- wall model tube samplers made of glass were pushed into the transparent soil. Movements within the soil body were recorded using digital photography; these images were later analysed by particle image velocimetry. The centreline strain path (CSP) of the sample during tube penetration was calculated and compared to an existing analytical model, and some degree of correlation was observed. However, it was shown that the CSP was not constant throughout the sample, but varied with depth below the base of the borehole. It was also noticed that, after tube penetration, some residual extension strain existed for soil on the centreline. To quantify the effects of sampler geometry parameters on the CSP, further experiments are required to gain an insight into the design of tube samplers, with the aim of producing high-quality soil samples without significantly raising the cost of site investigation.

Honeysuckle Drying by Using Hybrid ConcentratorPhotovoltaic-Thermal (PV/T) Dryer: An Experimental Study

This paper presents experimental performance of a concentrator photovoltaic thermal (CPV/T) dryer for drying of honeysuckle flowers. The dryer consists of a perspex box structure. Heat for drying is provided by the excess heat of concentrator PV module and one fan powered by this concentrator PV ventilate the dryer. To investigate the experimental performances of the solar dryer for drying of honeysuckle flowers, 2 full scale experimental runs were conducted. Of which one experimental runs were conducted by hot air and the drying air temperature varied from 65°C to 80°C, the drying time was 5 hours. The other t experimental runs were conducted for natural sun drying for comparison, and the drying time was 5 hours too. Experiments were conducted for drying of honeysuckle in the month of June, 2012. Various half hourly experimental data namely moisture evaporated, honeysuckle surface temperatures, ambient air temperature and humidity, etc. were recorded to evaluate heat and mass transfer for the proposed system. The experimental results show that the quality of hot air dried products in terms of color, form, texture, etc. was high-quality dried products.

Modeling the Dynamic Response of Wrap-Faced Reinforced Soil Retaining Walls

This paper describes the development of a numerical model for simulating the shaking table tests on wrap-faced reinforced soil retaining walls. Some of the physical model tests carried out on reinforced soil retaining walls subjected to dynamic excitation through uniaxial shaking tests are briefly discussed. Models of retaining walls are constructed in a perspex box with geotextile reinforcement using the wraparound technique with dry sand backfill and instrumented with displacement sensors, accelerometers, and soil pressure sensors. Results showed that the displacements decrease with the increase in number of reinforcement layers, whereas acceleration amplifications were not affected significantly. Numerical modeling of these shaking table tests is carried out using the Fast Lagrangian Analysis of Continua program. The numerical model is validated by comparing the results with experiments on physical models. Responses of wrap-faced walls with varying numbers of reinforcement layers are compared. Sensitivity analysis performed on the numerical models showed that the friction and dilation angle of backfill material and stiffness properties of the geotextile-soil interface are the most affecting parameters for the model response.