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1.
There is no better place to test life-saving resuscitation interventions than in the prehospital setting. Patients rarely survive cardiac arrest if resuscitation techniques have failed before leaving the scene. Also, paramedics are usually very experienced in key initial resuscitative techniques, and they routinely operate under strict paramilitary protocol, resulting in better study compliance. In addition, the large study populations that are derived from emergency medical services (EMS) systems lead to faster study completion and statistically stronger data. Most important, by reinforcing standardized care, rigidly scrutinized trials improve patient care, regardless of the effect of the study intervention. The success of productive EMS research centers requires routine communication between hospital and EMS administrators and their medical directors, designation of mutually acceptable data collectors who guarantee confidentiality, reciprocal exchange of study data provided as educational seminars to the hospitals, commitments to support the budget requests of an EMS program and appropriate system modifications, inclusion of EMS personnel in study design from the very beginning, prospective education of the medical community and media before protocol implementation, an authoritative grassroots medical director, and a paramedic supervisor system.  相似文献   
2.
The first known sex pheromone for the family Miridae is reported for the mullein bug,Campylomma verbasci (Meyer) (Heteroptera: Miridae). Extracts of and Porapak Q-trapped volatiles from females were attractive to males in field bioassays. Butyl butyrate and hexyl butyrate were the predominant compounds in the females' volatiles, but these compounds previously had been found to be inactive when released alone or in combination. Butyl butyrate in combination with an isolated trace chemical, (E)-crotyl butyrate (which was inactive alone), rivaled the attraction elicited by five live females. When synthetic butyl butyrate and (E)-crotyl butyrate in a 16: 1 ratio were released at 91 or 183 g/day, they comprised an effective attractant for male bugs.  相似文献   
3.
Capture of spruce beetles, Dendroctonus rufipennis, in multiple-funnel traps baited with frontalin and -pinene was reduced by up to 42% in the presence of synthetic (+)-exo- and (+)-endo-brevicomin, aggregation pheromones of the sympatric species Dryocoeles affaber. (±)-endo-Brevicomin was inhibitory to spruce beetles in two experiments and (±)-exo-brevicomin was inhibitory in one experiment, reducing spruce beetle trap catches by up to 87% and 75%, respectively. Spruce beetle trap catches were also reduced by 85% by (±)- or (+)-ipsdienol, but not by (–)-ipsdienol. Ips tridens, a second sympatric species, produces both enantiomers of ipsdienol in its pheromone blend. Responses by D. affaber to its own pheromone were significantly enhanced by addition of the spruce beetle lure. Enantiospecific pheromones of secondary competing species, or less costly racemic substitutes, may be useful for managing spruce beetles using competitive displacement or exclusion. Baiting susceptible hosts with pheromones of secondary species may enhance attack by secondary species, while partially repelling spruce beetles.  相似文献   
4.
Release of the antiaggregation pheromone, verbenone, at 3.8 mg/ day from a concentrated source within a multiple-funnel trap completely inhibited response by the mountain pine beetle (MPB),Dendroctonus ponderosae Hopkins, to attractive semiochemical lures. When aerial applications were simulated and verbenone was released at the same rate from beads lying in a 2×2-m area on the forest floor 15–35 cm below a trap, the response of the MPB was inhibited by only 50%. This reduced inhibition may be explained in part by the photoisomerism of verbenone. When exposed to full sunlight on two occasions, the times required for 50% of verbenone vapors to be converted to chrysanthenone were 75 and 100 min, respectively. Trap and tree-baiting experiments indicated no biological activity of chrysanthenone. Rapid photoisomerization could reduce the concentration of verbenone below biologically active levels and would allow the MPB to colonize trees close to already occupied hosts, contributing to the characteristic clumped distribution of MPB attack. The rate of verbenone photoisomerization may vary according to geographic location, stand elevation and density, and should be considered before verbenone is applied to control the MPB and other bark beetles.  相似文献   
5.
The responses ofIps pini (Scolytidae) to multiple-funnel traps baited with the pheromone, ipsdienol, and various monoterpenes were determined in stands of lodgepole pine in southern and central British Columbia.Ips pini was attracted to both ipsdienol and -phellandrene, demonstrating that -phellandrene is a kairomone for this species.Lasconotus complex (Colydiidae) and aCorticeus sp. (Tenebrionidae) were attracted to both ipsdienol and -phellandrene. TheCorticeus sp. exhibited a synergistic response to the combination of ipsdienol and -phellandrene; the responses of the other two species to the combination were additive. The predators,Thanasimus undatulus, Enoclerus sphegeus, andE. lecontei (Cleridae), were attracted to ipsdienol-baited traps, whileMonochamus clamator (Cerambycidae) andDendroctonus ponderosae (Scolytidae) were attracted to -phellandrene. Attraction of all eight species increased with increasing release rates of ipsdienol and/or -phellandrene.  相似文献   
6.
A two-choice feeding bioassay was used to investigate the intra-specific repellency of the larval oral exudate of eastern and western spruce budworms,Choristoneura fumiferana (Clem.) andC. occidentalis Free., respectively. Results of the bioassay indicated that feeding behavior on artificial diet-drop feeding stations was modified in the presence of exudate, with feeding stations treated with conspecific exudate being avoided when an untreated station was available 3 cm away. Feeding was suppressed when a single, exudate-treated station was provided, or when the treated and untreated stations were separated by only 1 cm. The repellent effect functioned both inter- and intraspecifically. When induced to produce exudate,C. occidentalis larvae were not immediately repelled by either their own or other individuals' exudate. However, 24 hr after induction, test larvae were repelled by exudate from either source. In both species, larval oral exudate probably functions to repel conspecific competitors.  相似文献   
7.
8.
Assembling 2D-material (2DM) nanosheets into micro- and macro-architectures with augmented functionalities requires effective strategies to overcome nanosheet restacking. Conventional assembly approaches involve external binders and/or functionalization, which inevitably sacrifice 2DM's nanoscale properties. Noble metal ions (NMI) are promising ionic crosslinkers, which can simultaneously assemble 2DM nanosheets and induce synergistic properties. Herein, a collection of NMI–2DM complexes are screened and categorized into two sub-groups. Based on the zeta potentials, two assembly approaches are developed to obtain 1) NMI-crosslinked 2DM hydrogels/aerogels for heterostructured catalysts and 2) NMI–2DM inks for templated synthesis. First, tetraammineplatinum(II) nitrate (TPtN) serves as an efficient ionic crosslinker to agglomerate various 2DM dispersions. By utilizing micro-textured assembly platforms, various TPtN–2DM hydrogels are fabricated in a scalable fashion. Afterward, these hydrogels are lyophilized and thermally reduced to synthesize Pt-decorated 2DM aerogels (Pt@2DM). The Pt@2DM heterostructures demonstrate high, substrate-dependent catalytic activities and promote different reaction pathways in the hydrogenation of 3-nitrostyrene. Second, PtCl4 can be incorporated into 2DM dispersions at high NMI molarities to prepare a series of PtCl4–2DM inks with high colloidal stability. By adopting the PtCl4–graphene oxide ink, various Pt micro-structures with replicated topographies are synthesized with accurate control of grain sizes and porosities.  相似文献   
9.
In the Docklands area of London lies the ‘Limehouse Link’, a dual-bore road tunnel used by around 80,000 cars each day. A monumental and highly expensive piece of construction, the Limehouse Link has nonetheless received almost no attention from architectural historians or others concerned with the history of construction, engineering or urban development.

This article provides an introduction to the Limehouse Link, explaining some of the fundamental characteristics of its construction and position in London's urban landscape. More importantly, the article then considers how one might understand an everyday yet monumental construction such as this: a tunnel without obvious aesthetic form, design intent or symbolic meaning, but which nonetheless has an undeniable presence in the city. The Limehouse Link is therefore interpreted in terms of the car driver's immersive experience of the tunnel, more active constructions of this experience through sensory qualities of sound, representations of the tunnel in different media and art, ways of knowing the history of Limehouse, and, in particular, as a kind of aesthetic experience. The article concludes that driving through the Limehouse Link is to engage in a different way of knowing the postmodern city.  相似文献   
10.
Antennally active, bark-derived, angiosperm volatiles were tested singly and in groups for their ability to disrupt the response of the Douglas-fir beetle (DFB), Dendroctonus pseudotsugae, to attractant-baited multiple-funnel traps. One compound, conophthorin, was active alone in reducing the response of beetles to the baited traps. Further experiments showed disruptive activity in two aliphatic green-leaf alcohols [1-hexanol and (Z)-3-hexen-1-ol], as well as guaiacol and benzyl alcohol, and three aliphatic aldehydes [nonanal, hexanal, and (E)-2-hexenal] but not in two aromatic aldehydes (benzaldehyde and salicylaldehyde). Every binary combination that included conophthorin or any two of the other groups, except aromatic aldehydes, significantly reduced the response of beetles to baited traps. Various ternary mixtures and the complete mixture of all the groups were generally the most effective treatments. These results provide evidence that DFBs recognize and avoid nonhosts while flying rather than landing on candidate hosts and testing them while in contact with the tree. Nonhost angiosperm bark volatiles may have practical utility on their own or in combination with the antiaggregation pheromone 3-methylcyclohex-3-en-1-one (MCH) to protect single trees, logs, or stands from attack by the DFB.  相似文献   
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