Small Entrance Research Articles

Thermal testing of the first mirror unit mock-up for H-alpha and visible spectroscopy in ITER

H-alpha and visible spectroscopy (HA&VS) diagnostic in ITER is aimed at the measurements of the intensity of hydrogen isotopes and of impurity lines in the SOL emission. It is based on the endoscope scheme with the first mirror unit (FMU) containing two mirrors (flat and aspheric) located behind a small entrance pupil and a discharge cleaning system. A primary candidate material for the FMU mirror is a single-crystal molybdenum (SC-Mo). A sandwich-like design is proposed, in which few small-sized SC-Mo plates are bound by a diffusive welding to a large-size polycrystalline Mo substrate. An acceptable welding regime is presented. A recent progress is discussed on the polishing of SC-Mo focusing mirrors up to 150mm diameter. Thermal tests of the molybdenum FMU mock-up had been performed. The FMU was heated up to 200°C whereas the mirror temperature was up to 300°C under the pressure of 8–9Pa. A technique for the quantitative assessment of the image quality (contrast and resolution) at the elevated temperatures has been suggested. As a result, a sub-mm shift of an image plane along the optical axis had been observed with no significant degradation of the image quality.

Enhanced release of the poorly soluble drug itraconazole loaded in ordered mesoporous silica

It is known that the energy of the amorphous state of itraconazole loaded in ordered mesoporous materials is high relative to that of the crystalline state and is responsible for enhanced solubility and dissolution rate. We investigated the effects of particle size (0.7–5 μm), mesostructure (2D p6mm, cubic Ia-3d and cubic Fm-3m) and pore size (2.2–15.4 nm) of mesoporous silicas on the release performance of itraconazole. Results indicated that the release performance was not influenced by the particle sizes tested here, that the release performance increased with increasing pore diameter due to the lower probability of drug molecules colliding to recrystallize in large pores, and that the release performance was decreased in the cage-type pore structure (Fm-3m) compared to that in the cylindrical pore structures (p6mm and Ia-3d) because of the small entrance to the cagelike pores that retards the drug release.

An experimental investigation into the colonization of concealed cadavers by necrophagous blowflies.

We used seven baited boxes with different combinations of access holes and odor diffusion surfaces to study the arrival of necrophagous flies. During laboratory experiments, 30 gravid Lucilia sericata females were kept in a chamber with one of the boxes. The box with the largest odor diffusion surface (99 cm2) combined with the lowest accessibility (one 1 cm2 entrance hole) was entered least (5 ± 3.7 flies per run). In contrast, the most frequently entered box (one 9 cm2 entrance hole with no additional odor diffusion surface) caught a mean of 24.6 ± 3.4 flies per run. These results indicate that 1) L. sericata entered nearly inaccessible places and 2) both odor diffusion and accessibility impacted the number of flies caught. During field experiments, the seven boxes were placed together outdoors. The box with the most entrances (ten 9-cm2 holes) caught the most flies (55.6–99.4% of the total). Only a few flies entered the other boxes. Access to the less accessible boxes (poor odor diffusion and small entrances) was also delayed. The major conclusions of the field experiments are that 1) boxes with low accessibility took longer to be accessed; 2) larger odor diffusion surfaces were more attractive to flies; and 3) flies accessed boxes more readily through larger holes than through an equivalent surface area made up of smaller holes. With these conclusions in mind, attempts to quantify the preappearance interval or to interpret the number of flies observed in indoor forensic entomology cases should be approached with caution.

Are tits really unsuitable hosts for the Common Cuckoo?

Avian brood parasites exploit hosts that have accessible nests and a soft insect diet. Common Cuckoo (Cuculus canorus) hosts were traditionally classified as suitable if both parameters were fulfilled or unsuitable if one, or both, were not. In line with this view, hole-nesting tits (Paridae) have become a text-book example of unsuitable Cuckoo hosts. Our extensive literature search for Cuckoo eggs hatched and chicks raised by hosts revealed 16 Cuckoo nestlings in Great Tit (Parus major) nests, 2 nestlings and 2 fledglings in Blue Tits (Cyanistes caeruleus), and 1 nestling in a Crested Tit (Lophophanes cristatus) nest. Our own data from natural observations and cross-fostering experiments concur with literature data that Great Tits are able to rear Cuckoo chicks to fledging. The natural observations involve the first known cases where a bird species became parasitized as a byproduct of nest usurpation (take-over). Surprisingly, Cuckoo chicks raised by Great Tits grew better than Cuckoo chicks raised by common hosts, even alongside host own chicks. The frequency of Cuckoo parasitism in tits may be underestimated by studying tits in artificial nest-boxes with small entrances that prevent Cuckoos from laying and/or fledging. Results support a view that host suitability is not a categorical parameter (host suitable or unsuitable) but a continuous phenomenon. Understanding the diversity of parameters that determine host selection by Cuckoos is limited, because studies on Cuckoo chick diet, growth, and survival in most hosts are rare. Therefore any data are valuable and provide indispensable material for future meta-analyses.

Parallel guidance endoscopic optical coherence tomography system for internal diagnosis through active cannulas

A parallel guidance endoscopic optical coherence tomography (OCT) system is proposed for minimally invasive internal inspection of inner organs or complex structures for diagnosis. The system is maneuvered to access the target using an active cannulas’ steerable structures. The integration of a specially designed linkage device with the developed system allows the OCT endoscope to scan with enhanced signal-collective performance, while maintaining its tip at a constant distance from the target, as well as expanding the scanning range. The proposed system is integrated with flexible active cannulas, and this prototype is used for testing. The test results show that the device reliably performs for biological samples. Thus, it could be implemented for various types of noninvasive diagnoses in situations involving small entrances or crooked passage to a target.

Approach on Pollution Gases Diffusion Path of Small Spacing Tunnel Entrance Based on CFD

Small spacing tunnel due to the special structure form and two tubes are only separated by a thin wall. This structure form is likely to cause secondary pollution, pollution gas discharged into the adjacent tunnel. This phenomenon will lead to increased ventilation system energy consumption. This paper analysis gas diffusion path between two adjacent tunnels, using CFD (Ansys Fluent). To relieve the pollution gases secondary pollution of tunnel portal area, using CFD analyzed gas diffusion path under different circumstances, for opening hole on the top of sunshades, extended of the wall between two adjacent tunnels and other programs, and identify more comprehensive disposal program.

Zebra finches select nest material appropriate for a building task

Across the animal kingdom, many animals build structures. One especially diverse example is that of nest building by birds. It remains unclear, however, what birds know or whether they learn about the structural aspects of the material with which they build a nest. Here we tested whether nest-building male zebra finches would choose the appropriate type of material when building in a novel situation. They did do this: males provided with a nestbox with either a small or a large entrance hole and with nest material of two types (‘long’ and ‘short’) chose the type of material that was appropriate for the box in which they built. Additionally, the birds' material use improved with experience: males building in nestboxes with small entrances became less choosy in their material choice as they became more skilled at inserting material of either length into their nestbox. The birds, therefore, first chose the appropriate materials for the nestbox in which they were building but then modified their handling skills so as to make use of all of the available material. How the cognitive abilities used in this nest-building context compare with those used in solving other physical problems such as tool use tasks is not yet clear.

On the formation of ethynylbiphenyl (C14D5H5; C6D5C6H4CCH) isomers in the reaction of D5-phenyl radicals (C6D5; X2A1) with phenylacetylene (C6H5C2H; X1A1) under single collision conditions

Reaction dynamics of the D5-phenyl radical with phenylacetylene were investigated in crossed molecular beams at a collision energy of 120.7kJmol−1 supported by ab initio calculations. The reaction displays indirect, complex forming scattering dynamics, and adduct formation, with D5-phenyl attacking the phenyl ring of phenylacetylene at the ortho, meta and para positions over small entrance barriers. The adduct (C6D5C8H6) undergoes hydrogen emission through tight exit transition states of 34–47kJmol−1 above the separated products. The phenyl addition–hydrogen elimination mechanism produces various ethynylbiphenyls exoergically by 25–38kJmol−1. No phenanthrene was formed under our experimental conditions.

Larger-scale fabrication of N-doped graphene-fiber mats used in high-performance energy storage

The N-doped graphene fibers mats (NG-FMs) have been fabricated through spinning GO into ethanol solution of hydroxylamine and following thermal treatment. The NG-FMs are flexible and possess pores with the large interior and small entrance. The results of characterization indicate that N has doped into the graphene sheets during the preparation of the fibers, and that the interplanar distance of the graphene sheets in the fibers has almost no change with the increase of the treating temperature. The capacitive properties of the NG-FMs have been investigated by electrochemical method using two-electrode symmetric capacitor test. The results show that the specific capacitance of NG-FMs can reach 188 F g−1 at scan rate of 5 mV s−1 and the capacitors assembled by them possess the high-rate capability (the impedance phase angle can reach −45° at 16.5 Hz) and good cycling stability. The energy density and power density of the capacitor can reach to 2.24 Wh kg−1 and 48.7 kW kg−1 at discharged current density of 300 A g−1 (excluding iR drop).

Nest cavity selection by the Siberian flying squirrel Pteromys volans

Populations of the Siberian flying squirrel Pteromys volans are declining as a result of insensitive forestry that has removed cavity trees. To conserve the cavities preferred by squirrels, we investigated the characteristics of the cavities they used as nests. We located 100 cavities with >3.0 cm entrance size (which they are able to enter), and investigated their use by the squirrels. We also recorded the entrance heights and entrance sizes of the cavities and the health and heights of cavity trees. The squirrels used 29 of 100 cavities. Entrance size and tree health strongly influenced cavity use, and entrance height had a weaker influence. Tree height was not correlated with cavity use. Squirrels preferred higher cavities with smaller entrances and on live trees. The entrance size of the cavities used was limited to ≤5.0 cm. Squirrels used 38% of live trees but only 14% of dead trees. In addition, the squirrels avoided cavities at low heights. They never used cavities 1.0 m height and with entrance sizes of 3.0 to ≤5.0 cm on live trees were preferred. We suggest that cavities with these characteristics should be conserved to protect the habitats of Siberian flying squirrels. Download the complete issue.

Methanol-to-Olefin Conversion over Zeolite Catalysts: Active Intermediates and Deactivation

Methanol-to-olefin (MTO) conversion over various zeolites with different topologies, Si/Al molar ratios, and crystallite sizes were investigated to verify the effects of pore shape and size, acidity, and external surface area on the catalytic activity, product selectivity, and deactivation. The IR and electron spin resonance (ESR) study of zeolite catalysts used in MTO also proceeded to deduce the active intermediates formed in their cages or pores. The zeolites with 8 membered-ring (MR) pore entrances such as CHA, ERI, LTA, and UFI commonly exhibited high selectivity to lower olefins due to their small entrances, but the CHA catalyst with the smallest cage maintained its activity longer than other 8MR zeolites. The slow condensation of polymethylbenzene (PolyMB) to polyaromatic hydrocarbons (PAH) on MOR zeolite with a high Si/Al molar ratio due to its low concentration of strong acid sites resulted in a slow deactivation. The extremely small crystallites of H-SAPO-34 and H-ZSM-5 less than 100 nm showed an adverse effect in MTO; while the large crystallites above 1,000 nm also exhibited poor catalytic performance because of their small external surface. The study of IR regarding the adsorbed and occluded materials on zeolites demonstrated the effect of pore shape and size on the active intermediates: the zeolites with larger pores and cages allowed the formation of alkylbenzenes with long alkyl groups which preferred to be condensated to PAH. The well-resolved hyperfine splitting of ESR spectra observed on H-SAPO-34 used in MTO clearly illustrated the presence of hexamethylbenzenium radical cations. The small intersections of phosphorous-modified H-ZSM-5 allowed the formation of tetramethylbenzenium radical cations in MTO. The formation of PolyMB radical cations, their role as active intermediates and the effect of topology, acidity, and crystallite size of zeolites on their deactivation were discussed.

An empirical investigation on the demographic characteristics of specialized visitors and their preferences to use up-country tea plantations as nature tourism sites

Up country tea plantations have been emerging as sites for nature tourism for both local and foreigntourists who were earlier used to visit traditional tourism sites (e.g. Anuradhapura, Pollonnaruwa andSeegiriya) predominantly. In light of this, evaluation of what characteristics associated with thesevisitors. and to which extent, have an impact on a selection of nature tourism sites available in theseplantations as their choice has become important, since that information can be used to formulatea market-friendly environmental policies to promote it. Those specialized (i. e. those who visit an Up Country tea plantation for the first time basedon the information they received from an external source and those who repeated) were selected asthe cases for data collection (n = 120). A semi-structured questionnaire was used in this respect atseven purposely-selected entry points to the plantations located in the Nuwara-Eliya district. Both qualitative and quantitative data analysis techniques were used. The results indicate that, ingeneral, young people (i. e. 56% of sample within 20 - 29 years); those who married (59%); and withaverage house hold size of three to four members (84%); with high income level (i.e. 43% of sampleabove the Rs. 50,000 per month). and possess a degree or equivalent (60%) decided to enjoy thesesites. Majority of them were employed at private sector enterprises as middle to top-level managers.In terms of reasons for their visit, about 63 percent of visitors indicated aesthetics/scenic beautyfollowed by bird watching (52%), forest trekking (46%), mountain climbing (44%), hiking (42%) andsafari (30%). Regarding the existing facilities at these sites, about 60 and 91 percent of local andforeign visitors, respectively, were satisfied. Several visitors (45%) proposed that the existinginfrastructure facilities to be improved. With respect to entry fee, 65 percent of the visitors preferredto make the payment as a whole and rest as a small entrance fee with an additional fee for eachactivity. The results highlight that government agencies should cooperate with plantation companiesto promote nature tourism as a viable non-crop diversification mechanism.

TU‐A‐116‐11: Maximum Patient Skin Dose From Interventional Radiology Procedures and Definition of Alert Thresholds

Purpose: To determine patient maximum skin dose (MSD) from interventional radiology procedures and define alerts using kerma‐area product (KAP) and cumulative air kerma (CK) values displayed by equipment manufacturers. Methods: In the framework of EURADOS WG12, nine European Countries participated with measurements of patient maximum skin dose performed during three different types of interventional procedures: neuro‐embolizations (NE), chemo‐embolizations (CE), and coronary angioplasties (PTCA). For each procedure, KAP, CK and fluoroscopy time (FT) values were also collected, as well as other parameters related to dosimetry, such as peak voltage, mAs value, filtration, beam entrance angle and total number of images. Correlations between MSD and displayed dose parameters were investigated. Results: In general, maximum skin dose is weakly correlated to both KAP and FT. Meanwhile, skin dose is quite well correlated with cumulative air kerma. In particular, the best correlation was found for CE procedures, for which relatively small entrance angles are used for the incident beam compared to PTCA and NE procedures. Conclusion: This work provides patient dose levels from some frequent interventional radiology procedures and indicates that CK could be used to define alerts helpful for operators to identify situations associated to high probability of exceeding the dose threshold for deterministic effects. However, definition of alerts applicable at European level remains difficult because of other factors affecting maximum skin dose, including operator's experience and methodology. Funded in the framework of EURADOS WG12.

Plasma tests of diagnostic mirrors for ITER purposes

One of the main problems of ITER optical diagnostics is the degradation of collecting mirrors by erosion or impurity deposition. It is suggested to reduce the degradation by small entrance pupil in optical system. The prototype of endoscope optical system for H-alpha ITER diagnostics is under testing in T-10 tokamak. It has entrance pupil of 1mm diameter. Three molybdenum mirrors were tested between 1 and 3 years. In spite of local degradation or surface damages appeared after 2 years of operation, the diagnostics remained functional.In parallel, the first mirror assembly (FMA) with 4mm pupil was tested in a magnetron sputtering installation. Deuterium pressure was 0.7Pa during magnetron discharge with 1A current. Estimated flux of aluminum and carbon atoms was about 1014atcm−2s−1 on the FMA entrance pupil. As a result, FMA molybdenum mirrors preserved their reflectivity after 40h of exposure which can be considered as 400 ITER pulses. Thereby small entrance pupil appears as a good solution for first mirror protection.

UZM-9 제올라이트에서 메탄올의 올레핀으로 전환반응: 전이금속 이온 교환이 촉매의 활성저하에 미치는 영향

구리, 코발트, 니켈, 철의 전이금속 이온을 교환한 LTA 골격구조의 UZM-9 제올라이트에서 메탄올이 저급올레핀으로 전환(Methanol-to-Olefin: MTO)되는 반응을 조사하여 전이금속 이온 교환이 촉매의 활성저하에 미치는 영향을 고찰하였다. 전이금속 이온 교환에 따른 UZM-9의 결정구조, 결정 모양, 세공구조, 산성도 변화는 크지 않았다. UZM-9은 둥지 입구가 작아 MTO 반응에서 저급올레핀에 대한 선택도가 높지만, 둥지가 커서 활성중간체인 헥사메틸벤젠 등 폴리메틸벤젠이 쉽게 고리화축합되어 다고리 방향족화합물이 많이 생성되므로 활성저하가 빠르다. 그러나 구리와 코발트 이온을 교환하면 MTO 반응에서 UZM-9의 활성저하가 느려졌다. MTO 반응 중 생성되는 폴리메틸벤젠 양이온 라디칼과 전이금속 이온의 상호작용으로 활성중간체가 안정화되어 활성저하가 느려졌다. The effect of transition metal ion exchange into UZM-9 zeolite with LTA framework on its deactivation in methanol-to-olefin (MTO) conversion was discussed. The ion exchange of copper, cobalt, nickel, and iron did not induce any notable change in the crystallinity, crystal morphology, and acidity of UZM-9. The small cage entrance of UZM-9 caused the high selectivity to lower olefins in the MTO conversion, while its large cages allowed the rapid further cyclecondensation of active intermediates, polymethylbenzenes including hexamethylbenzene, resulting in a rapid deactivation. The UZM-9 containing copper and cobalt ions showed considerably slow deactivations. The interaction between transition metal ions and polymethylbenzene cation radicals, the active intermediates, generated in the MTO conversion stabilized the radicals and slowed down the deactivation of UZM-9.

House Wrens Alter Nest Architecture to Compensate for Cavity Vulnerability

Abstract We compared House Wren (Troglodytes aedon) nests in nest boxes with either small (28 mm) or large (38 mm) entrance holes. Spring clutch size did not differ between wrens using boxes with large and small holes. Nests in boxes with large holes had a significantly taller ‘berm’ of sticks between the box entrance and the nest cup than did nests in boxes with small holes. This was true even when the same wren pairs were given boxes with different-size holes for spring and summer nests. We compared the difficulty of touching the eggs when we removed the frontplate of the nest box as an alternative measure of nest vulnerability to predators and brood parasites. There was a significant association between hole size and accessibility: boxes without the protection of a small entrance hole were far more likely to be categorized as ‘inaccessible.’ We found a similar relationship between berm height and nest architecture: nests with tall berms were generally less accessible than were nests with shorter berms....

Ground-based survey methods both overestimate and underestimate the abundance of suitable tree-cavities for the endangered Swift Parrot

Most cavity-dependent species select tree-cavities with a narrow range of characteristics so that only a small subset of available cavities may be suitable for any species. Most surveys for tree-cavities are done from the ground using binoculars to reduce effort, but this technique is prone to error. These errors are likely to contribute to the loss of the cavity resource when used to inform conservation efforts for cavity-dependent species. The Swift Parrot (Lathamus discolor) is an endangered migratory bird threatened by ongoing removal of cavity-bearing trees by production forestry. We climbed trees with cavities used for nesting by Swift Parrots and determined that they prefer cavities with small entrances, deep chambers and wide floors. Such cavities are rare and occur in large trees that support higher than average numbers of tree-cavities. Importantly, cavities used by Swift Parrots were also likely to be both overestimated and underestimated using ground-based surveys, and without calibration by climbing, the size and direction of survey error could not be determined. We conclude that the most effective way to gain detailed information about the characteristics and abundance of tree-cavities is to climb a representative sample of trees to calibrate ground-based methods for a specific ecosystem.

Lessons learned from war: a comprehensive review of the published experiences of the Iranian neurosurgeons during Iraq-Iran conflict and review of the related literature.

Background and Objective: The present study was aimed to review the articles published by Iranian neurosurgeons regarding their experiences during Iraq-Iran 8-year conflict and compare it with reports from other conflicts. Methods: The relevant papers and studies, published up to December 2011, were searched from three databases including MEDLINE, and two Iranian databases of IranMedex and Scientific Information Database with the keywords Iran, Iraq, conflict, battle, war, traumatic aneurysm (TA), post-traumatic epilepsy (PTE), brain infection, penetrating head wound (PHW), cerebrospinal fluid (CSF) leakage, spine injury and peripheral nerve injury. Results: A total of twenty-eight papers were found that presented PHW, development of TA, infections, PTE and peripheral nerve injuries. There were two different protocols for management of PHWs: radical surgery and minimal debridement protocol. The overall CNS infection rate was 10%. The cumulated incidence of TA was 6%. Conclusion: Conservative minimal debridement of the wounds was indicated in patients with small entrance wounds, or those with GCS≥ 8 and no progressive neurological deficit. To diagnose TA before rupture angiography was performed in patients with shells or bone fragments, passed through the crowded vasculature, or with large/delayed hematoma, or if the surgeon had high index of suspicion based on neuroimaging and early debridement surgery . Surgery in a well-equipped nearby hospital after quick and safe evacuation of the victims by trained-salvaging-ancillary groups, administration of broad-spectrum antibiotics and proper antiepileptic drugs decreased the morbidity and mortality of casualties after PHW in war situations. The biases of the case selection, data collection, confounders and decreasing biases by conducting blinded controlled clinical trials were discussed.__________________________________________________________ Full text of this presentation was published at the World Neurosurgery: http://www.worldneurosurgery.org/article/S1878-8750%2812%2900895-9/abstract

The breeding performance of Blue Tits Cyanistes caeruleus in relation to the attributes of natural holes in a primeval forest

SUMMARY Capsule Blue Tits nested in non-excavated holes with narrow openings, typically in live trees, which reduced both the risk of nest predation and of nest soaking. Aims To describe patterns of nest-site utilization by Blue Tits in primeval conditions, to examine the influence of various hole attributes on nesting success, and to test the adaptive value of nest-site choice. Methods Observations of birds living in undisturbed conditions in a strictly protected part of the Białowieża National Park (Poland) during 37 breeding seasons, coupled with measurements of hole attributes and observations of nests' fate. Results Tree species used for breeding differed among habitats. Nest holes were situated mainly in trunks of living trees, were non-excavated, with narrow slit-like openings, and had relatively small bottoms. Nests were lost mostly to predation and soaking. Adults were frequently killed on nests. Broods were more successful in holes with a smaller entrance, smaller bottom, and in nests situated further from the hole entrance. Conclusion The features of Blue Tit holes (strong walls, narrow entrances and nests moderately deep below the entrance) probably constitute adaptations to the need to evade predators while keeping the contents of the nest dry and adequately illuminated.

Habitat Selection and Reproductive Success of Lewis's Woodpecker (Melanerpes lewis) at Its Northern Limit

Lewis's Woodpecker (Melanerpes lewis) has experienced population declines in both Canada and the United States and in 2010 was assigned a national listing of threatened in Canada. We conducted a two-year study (2004–2005) of this species at its northern range limit, the South Okanagan Valley in British Columbia, Canada. Our main objective was to determine whether the habitat features that influenced nest-site selection also predicted nest success, or whether other factors (e.g. cavity dimensions, clutch initiation date or time of season) were more important. Nest tree decay class, density of suitable cavities and total basal area of large trees were the best predictors of nest-site selection, but these factors were unrelated to nesting success. Estimates of demographic parameters (mean ± SE) included daily nest survival rate (0.988±0.003, years combined), nest success (0.52±0.08), clutch size (5.00±0.14 eggs), female fledglings per successful nest (1.31±0.11), and annual productivity (0.68±0.12 female fledglings per nest per year). Although higher nest survival was associated with both early and late initiated clutches, early-initiated clutches allowed birds to gain the highest annual productivity as early clutches were larger. Nests in deep cavities with small entrances experienced lower predation risk especially during the peak period of nest predation. We concluded that nest-site selection can be predicted by a number of easily measured habitat variables, whereas nest success depended on complicated ecological interactions among nest predators, breeding behaviors, and cavity features. Thus, habitat-based conservation strategies should also consider ecological factors that may not be well predicted by habitat.