Nickel-titanium versus stainless-steel finger spreaders in curved canals

Fibro-osseous lesions of the sinonasal region are relatively frequent, but those strictly confined to the nasal cavity are rare. We report an atypical fibro-osseous lesion in the nasal cavity and describe its radiological features. The differential diagnosis is discussed.     

Comparing Transition-Edge Sensor Response Times in a Modified Contact Scheme with Different Support Beams

We present measurements of the thermal conductance, G, and effective time constants, \(\tau \) , of three transition-edge sensors (TESs) populated in arrays operated from 80–87 mK with T \(_\mathrm{C}\)   \(\sim \)  120 mK. Our TES arrays include several variations of thermal architecture enabling determination of the architecture that demonstrates the minimum noise equivalent power, the lowest \(\tau \) , and the trade-offs among designs. The three TESs we report here have identical Mo/Cu bilayer thermistors and wiring structures, while the thermal architectures are: (1) a TES with straight support beams of 1 mm length, (2) a TES with meander support beams of total length 2 mm and with two phonon-filter blocks per beam, and (3) a TES with meander support beams of total length 2 mm and with six phonon-filter blocks per beam. Our wiring scheme aims to lower the thermistor normal state resistance R \(_{N}\) and increase the sharpness of the transition \(\alpha =\)  dlogR/dlogT at the transition temperature T \(_\mathrm{C}\) . We find an upper limit of \(\alpha \) given by ( \(25\pm 10\) ), and G values of 200 fW/K for (1), 15 fW/K for (2), and 10 fW/K for (3). The value of \(\alpha \) can be improved by slightly increasing the length of our thermistors.     

Sub-Kelvin Thermal Conductivity and Radioactivity of Some Useful Materials in Low Background Cryogenic Experiments

We present measurements of the thermal conductivity between 0.05 and 1 K, and radioactive contamination levels, for some thermally isolating materials. TIMET Ti 15-3-3-3, Mersen grade 2020 graphite, Vespel SP-1, Vespel SP-22, Vespel SCP-5000, Vespel SCP-5050, Graphlite CFRP, and a Kapton/epoxy composite are all investigated. Thermal conductivities were measured using a single-heater longitudinal heat flow method. Material radioactivity was determined for the materials at a low background counting facility using a high-purity gamma detector and GEANT4 Monte Carlo simulations.     

Effectiveness of chlorine dioxide in disinfection on two soft denture liners

OBJECTIVE: The purpose of this study was to evaluate a hydroxylapatite-based material and calcium sulfate when each was used under a resin-modified glass ionomer cement to repair furcation perforations. STUDY DESIGN: Perforations of pulp chamber floors were made in 72 teeth of 9 dogs. Perforations were divided into 3 equal-sized groups and repaired with resin-modified glass ionomer either alone or over an artificial floor. The artificial floor was either a hydroxylapatite-based material or calcium sulfate. Three dogs were killed at each of 3 intervals (1, 3, and 6 months). The tissue response to the tested materials was evaluated clinically, radiographically, and histologically. RESULTS: The hydroxylapatite-based material showed the highest radiographic success; this was followed by calcium sulfate and glass ionomer. From histologic evaluation, the average success rate was found to be 67% for calcium sulfate, 62% for the hydroxylapatite-based material, and 59% for glass ionomer. However, there was no statistical significant difference with the resin-modified glass ionomer when it was used alone and when it was used over a barrier. There was also no significant difference between the hydroxylapatite-based material and the calcium sulfate when they were used as artificial floors. CONCLUSION: The use of an artificial floor may not be necessary when flowable resin-modified glass ionomer cements are used.     

Small Business in the Face of Crisis: Identifying Barriers to Recovery from a Natural Disaster1

The crisis management literature has not dealt in depth with small business response to disasters. This study takes a qualitative approach to consider how small businesses respond to and recover from a large disaster, by interviewing stakeholders in five different communities in the Gulf Coast of the United States. Events that are considered to be crises in nature are usually characterized by high consequence, low probability, ambiguity, and decision making time pressure. Hurricane Katrina and its aftermath caused small business owners in the U.S. Gulf region to experience each of these. Findings include lack of planning by small business; vulnerability to cash flow interruption; lack of access to capital for recovery; problems caused by federal assistance; and serious infrastructure problems impeding recovery.     

The life satisfaction chart: perceptions of the course of subjective experience

The Life Satisfaction Chart is presented as a method for studying perceptions of the course and determinants of life satisfaction. Analyses of reports from forty-five men and forty-six women in the Oakland Growth Study indicated the following: (1) Early-maturing boys, particularly in the working class, recollected their early adolescence as more satisfying than did the late-maturing boys, while early-maturing girls remembered early adolescence as less satisfying. (2) Upward social mobility was associated with an increase in reported life satisfaction for both sexes, but at a statistically significant level for men only. Unexpectedly, both men and women who were upwardly mobile recollected their childhoods as less satisfying than did the downwardly mobile. (3) Women rated above the mean in physical attractiveness during high school did not recall their teen-age years as more satisfying than those below the mean. The top quartile, however, did recollect these years as more satisfying than the bottom quartile. (4) Both men and women rated high on use of the defense mechanism of denial reported higher levels of retrospective life satisfaction.     

基于模糊控制的自供能无线传感器网络分簇算法

现有自供能无线传感器网络（WSN）分簇算法较少考虑网络最优分簇数,导致网络能量消耗过快,全网能耗不均衡。针对这个问题,提出了基于模糊控制的自供能WSN分簇算法（EH-FLC）。首先,在网络能量消耗模型中引入太阳能补给模型,得出每一轮次网络能量总消耗与网络分簇数目的函数关系,并对其求导从而得到网络的最佳分簇数。然后,利用双层模糊决策系统来评定网络中的节点能否成为簇头节点。先将节点剩余能量、相邻节点数作为判定指标输入第一层（能力层）对所有节点进行筛选,得到备选簇头节点;再将中心度参数、邻近度参数作为判定指标输入第二层（协作层）对备选簇头节点进行筛选,得到网络簇头节点。最后,通过Matlab仿真分析了该算法的网络生存周期、网络能量消耗和网络吞吐量等性能指标,与低功耗自适应集簇分层型协议（LEACH）、改进的非均匀分簇路由算法（WUCH）和利用双层模糊控制的簇头选择算法（CTLFL）相比,该算法在网络工作寿命上分别提高了约1.4倍、0.4倍和0.6倍,网络吞吐量上分别提高了约20倍、1.5倍和1.28倍。仿真结果表明所提算法在网络生存周期和网络吞吐量方面的性能较优。     

Morphogenetic mechanisms of epithelial tubulogenesis: MDCK cell polarity is transiently rearranged without loss of cell-cell contact during scatter factor/hepatocyte growth factor-induced tubulogenesis

Many organ systems are composed of networks of epithelial tubes. Recently, molecules that induce development of epithelial tubules and regulate sites of branching have been identified. However, little is known about the mechanisms regulating cell rearrangements that are necessary for tubule formation. In this study we have used a scatter factor/hepatocyte growth factor-induced model system of MDCK epithelial cell tubulogenesis to analyze the mechanisms of cell rearrangement during tubule development. We examined the dynamics of cell polarity and cell-cell junctions during tubule formation and present evidence for a multistep model of tubulogenesis in which cells rearrange without loss of cell-cell contacts and tubule lumens form de novo. A three-dimensional analysis of markers for apical and basolateral membrane subdomains shows that epithelial cell polarity is transiently lost and subsequently regained during tubulogenesis. Furthermore, components of cell-cell junctional complexes undergo profound rearrangements: E-cadherin is randomly distributed around the cell surface, desmoplakins I/II accumulate intracellularly, and the tight junction protein ZO-1 remains localized at sites of cell-cell contact. This suggests that differential regulation of cell-cell junctions is important for the formation of tubules. Therefore, during tubulogenesis, cell-cell adhesive contacts are differentially regulated while the polarity and specialization of plasma membrane subdomains reorganize, enabling cells to remain in contact as they rearrange into new structures.