Investigation of Wickless Heat Pipe Performance Filled With R134a

The wickless heat pipe (theroosyphon) is ordinate of three divisions the condenser, evaporator and insulated region (adiabatic region). In this work, the condenser and evaporator regions are made of copper tube with a length of 300 mm, for each an exterior diameter of 28.2 mm and an interior diameter of 26.4 mm. While the insulated region has a length of 400 mm and an exterior diameter of 28.2 mm. The evaporator region of the heat pipe bounded by a coiled heat source that represented the heat source. The condenser is encapsulated in a plastic cylinder to accommodate the flow of the cooling water. Thermosyphon has been filled by R- 134a working fluid. The effect of heat input, filling ratio and sink temperature were all tested and measurement. The results showed that the heat transfer performance increases when the applied energy to the evaporator increases while the total heat transfer efficiency of the heat pipe increases the gradient temperature between the medium of the evaporator and the condenser increases. The optimum fill rate is 119 % (250g), the sink temperature is 20°C, and it has been found to be suitable for optimum heat pipe performance.

Abstract 34: Transcranial Detection and Classification of Stroke Using a Noninvasive Handheld Portable Device

Introduction: Existing paradigms for stroke diagnosis typically involve computed tomography or magnetic resonance imaging to classify ischemic versus hemorrhagic stroke variants, as treatment for these subtypes varies widely. Delays in diagnosis and transport of unstable patients may worsen neurological status. Here, we demonstrate feasibility of rapid and accurate bedside stroke detection using a novel, handheld portable eddy current damping imaging device in live human clinical ischemic and hemorrhagic stroke settings. Methods: Copper wire was wound around an 11.4cm plastic cylinder to create a large solenoid coil and connected to an inductance-to-digital converter. Institutional Review Board approval was obtained and patients with hemorrhagic or ischemic stroke were recruited. The sensor coil was tangentially rotated across 8 rows on the patient’s head circumferentially. Data was plotted as a 2D heatmap to predict lesion type and location. For 3D figures, the 2D image was processed to convert the stroke-affected area from white to red (hemorrhage) and black to white (ischemia). Results: Consent, positioning each patient, and scanning with the sensor took roughly 15 minutes from start to end for each participant enrolled in our study and occurred at the patient bedside (n=8). Figure 1a and 1d show the location and type of lesion, Figure 1b and 1e show the 2D prediction heatmap generated after scanning hemorrhagic and ischemic stroke respectively, and Figure 1c and 1f show 3D reconstructed images of stroke location and subtype. Conclusion: We show that diagnosis of stroke may potentially be reduced from several hours to minutes, with additional spatial localization of intracranial hemorrhage, thereby rapidly guiding time-sensitive medical decisions for clinical intervention such as tPA. The sensor additionally detects ischemic and hemorrhagic lesions located deep inside the brain, and its range can be selectively tuned during sensor design and fabrication.

Canine collars: an investigation of collar type and the forces applied to a simulated neck model

BackgroundDog collars have the potential to cause harm when the dog pulls on the lead. This study aimed to determine the effects of collar type and force applied using the lead on the pressure on a simulated neck model.MethodsSeven collars and a slip lead were tested on a canine neck model. This consisted of a plastic cylinder ‘neck’, with a pressure sensor beneath the collar. A range of forces were applied to the lead representing different interactions: firm pull (40 N), strong pull (70 N) and jerk (mean force 141 N). Contact area of the collar and pressure on the neck were recorded.ResultsCollars exerted a pressure of between 83 kPa and 832 kPa on the model neck. There was a significant effect of collar type (F(7)=25.69, P<0.001) and force applied (F(2)=42.60, P<0.001) on the pressure exerted on the neck. Collar type (χ(7)=64.94, P<0.001), but not force applied (χ(2)=3.20, P=0.202), affected the contact area that the pressure was exerted over.ConclusionVariation in the pressures exerted on the neck may have implications on comfort and the potential to cause injury. No single collar tested provided a pressure considered low enough to mitigate the risk of injury when pulling on the lead.

Dynamic population of N2-fixing cyanobacteria in an organic rice field

Hendrayanti D, Rusmana I, Santosa DA, Hamim. 2019. Dynamic population of N2-fixing Cyanobacteria in an organic rice field. Biodiversitas 20: 2883-2890. The existence of free living N2-fixing cyanobacteria in rice fields has been acknowledged as an advantage for rice crops. At present, implementation of organic rice-systems has been increasing as an alternative way for keeping rice fields healthy. Therefore, investigation of N2-fixing cyanobacteria as a part of the soil components is important. Dynamic populations of the filamentous N2-fixing cyanobacteria assemblage in organic rice field at Ciparay, South Bandung, was investigated during the crop’s growth cycle (January-March 2018). Soil samples were collected from four plots of 20 ha rice fields. At each plot, soil from three random stations with three replications was taken using a 3-cm-diameter plastic cylinder. Composite samples from each station were analyzed for colony enumeration (TPC method), relative abundance and frequency, and species identification. The results show that population reached peak on the 80 days after planting (194 x 106 cfu/g soil). Species number decreased following increased density of the rice canopy. Among the 23 morphospecies found along the rice growth, four species were always found during all stages of growth: Halotia wernerae CSO2, Roholtiella mojavensis CSO6, Hapalosiphon welwitschii CSO7, and Desmonostoc danxiaense CSO3. The community of N2-fixing cyanobacteria found in the organic rice field was different to those reported from non-organic rice field.

Terrestrial isopods associated with shallow underground of forested scree slopes in the Western Carpathians (Slovakia)

The shallow underground of forested scree slopes represents a little-studied subterranean biotope. In this paper, species diversity and depth distribution of terrestrial isopod communities studied in the depth profile (5–95 cm from the surface) of eight forested scree slopes in the Western Carpathians (Slovakia) is discussed. The southern edge of the Western Carpathians where the study sites are located represents the northernmost limit of distribution of obligate subterranean fauna in Europe. The sites differ from each other in type of bedrock, forest composition, slope aspect, and altitude. To sample isopods, a set of three subterranean pitfall traps consisting of a plastic cylinder (Ø 110 mm) and ten plastic cups was buried in each studied scree slope. In total, 252 isopods belonging to eleven species were sampled (1–5 species per site). Of the species found, the blind and depigmented Mesoniscusgraniger was the sole species closely associated with deeper parts of the depth profile and was present in most of the sites studied. Another ten species were represented by a small number of individuals and their occurrence deeper in the scree slope profile was rather accidental. A comparison between winter and summer periods indicates apparent differences in seasonal activities of isopods. Ethylene glycol seems to be more appropriate fixative solution for trapping isopods than formaldehyde.

Dynamics of collembolan communities inside the forested scree slope

The monthly dynamics of collembolan communities was studied over a year-long period in the depth profile of forested scree slope in the karst area of the Čierna hora Mts. (Western Carpathians, Slovakia). Collembola were sampled using non-baited subterranean traps consisted of a plastic cylinder with the small openings drilled around at 10 horizontal levels (5 – 95 cm), and a system of 10 plastic cups connected to each other by a helical rod and nuts. The plastic cylinder, after being buried in the slope profile, served as a protective casing for inserting the plastic cups filled with the preservative solution. The cups inside the cylinder were placed right under the openings on the cylinder perimeter, enabling to trap specimens in the particular depth. The temperature was measured continuously throughout the study at four-hour intervals using thermo-data loggers affixed to the wall of the plastic cups. During the year, the monthly temperature means on the surface ranged between 0.2°C (January) to 16.6°C (August) while the monthly temperature means at the depth of 95 cm ranged between 3.5°C (April) to 15.2°C (September). Monthly temperature ranges varied from 5.0°C (February) to 12.5 °C (October) on the surface and from 0.5°C (February, April) to 4.5 °C (July) at 95 cm. A total of 60 collembolan species were identified, among them 27 trogloxenes, 19 subtroglophiles, 12 eutroglophiles and 2 troglobionts. Fluctuations of the locomotory activity during the year were observed in all four categories of Collembola and at all depths. Redundancy analysis (RDA) revealed collembolan activity to be substantially affected by the thermal conditions fluctuating over the year. Most eutroglophiles and troglobionts, associated with deeper layers of the scree slope, preferred rather lower temperature ranges and were typical of the autumn months.

In vitro protocol for validating interface pressure sensors for therapeutic compression garments: Importance of sphygmomanometer placement and initial cuff diameter

An optimal protocol is needed to validate the performance of future interface pressure sensors for compression garments when using a sphygmomanometer. PicoPress® was used on a rigid plastic cylinder (r=4 cm). An FDA-cleared aneroid sphygmomanometer was used to apply pressures from 10-60 mmHg with a diameter of 8 cm or 12 cm placed either beneath the sphygmomanometer’s airbag or fabric cuff. A two-tail t-test was performed (P<0.05 for significance) for all applied pressures. PicoPress® outputs vary with sensor placement (airbag vs fabric cuff) and the initial cuff diameter. Sensor placement overlying the sphygmomanometer’s fabric cuff compared to the airbag led to significantly higher pressures (37%-135%) depending on the cuff diameter size. These differences were nearly all statistically significant (P<0.05). Validation of new interface pressure sensors deploying a sphygmomanometer for calibration should specify the location of sensor placement location and initial diameter with a preference for placement under the airbag.

Development of a ‘lure and kill’ technique for apple leafcurling midge, Dasineura mali

Apple leafcurling midge (ALCM) is an important quarantine pest of New Zealand apples. Current methods for ALCM control have difficulty meeting the strict phytosanitary standards of some export markets. ‘Lure and kill’ is a new strategy against this pest, in which males are attracted to an insecticide-treated substrate where they collect a lethal dose. Trials were conducted using a gel matrix “Specialized Pheromone & Lure Application Technology” (SPLATâ„¢) to dispense and release the ALCM sex pheromone and the insecticide permethrin. Lures using SPLATâ„¢ were placed within plastic cylinder traps that collected the dead midges so they could be counted to determine treatment efficacy. The size, shape and age of SPLATâ„¢ spots influenced midge catches. Higher catches occurred with spots having a larger quantity of pheromone, greater surface area of SPLATâ„¢, or with fresh material. The implications for the development of a lure and kill strategy for ALCM are discussed.

Simulation of ERT surface-to-tunnel measurements.

The applicability of surface-to-tunnel electrical resistance tomography (ERT) measurements using a simulation tank for imaging subsurface targets is studied in this work. The tank was filled with water and inside of it was placed firmly a plastic construction where all targets were placed. Some of the targets that used were: a void plastic cylinder (resistive target) and metal plates (conductive target). Data were collected with a multichannel resistivity meter. The initial scope for these tests was to verify the reliability of developed inversionsoftware which was modified to cope with the specific measurements (surface-totunnel). Furthermore, during several experiments different electrode arrays (standard as well as new optimized) were validated. In our attempt to show the advantages of surface-to-tunnel measurements we analyzed the resolution for each configurationof traditional (surface) and surface-to-tunnel arrays. Studies also included testing the electrode displacement effect and also the effect of the tunnel size into the measurements.