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Abstract. Seismic techniques provide the highest-resolution measurements of the structure of the crust and have been conducted on a worldwide basis. We summarize the structure of the continental crust based on the results of seismic refraction profiles and infer crustal composi-tion as a function of depth by comparing these results with high-pressure laboratory measure-mentsof seismic velocity for a wide range of racks that are commonly found in the crust.. The thickness and velocity structure of the crust are well correlated with tectonic province, with extended crust showing an average thickness of 30.5 km and orogens an average of 46.3 km. Shields and platforms have an average crustal thickness nearly equal to the global average. We have coiTected for the nonuniform geographical distribution of seismic refraction profiles by estimating the global area of each major crustal type. The weighted average crustal thick-ness based on these values is 41.1 km. This value is 10 % to 20 % greater than previous esti-mates which underrepresented shields, platforms, and orogens. The average compressional wave velocity of the crust is 6.45 kmls, and the average velocity of the uppermost mantle (Pn velocity) is 8.09 kmls. We summarize the velocity structure of the crust at 5-km depth inter-vals, both in the form of histograms and as an average velocity-depth curve, and compare these

A preliminary unedited version of this paper was incorrectly published as part of Volume

I investigate how social embeddedness affects an organization’s acquisition and cost of financial capital in middle-market banking—a lucrative but un-derstudied financial sector. Using existing theory and original fieldwork, I develop a framework to explain how embeddedness can influence which firms get capital and at what cost. I then statistically examine my claims using national data on small-business lending. At the level of dyadic ties, I find that firms that embed their commercial transactions with their lender in social attachments receive lower interest rates on loans. At the network level, firms are more likely to get loans and to receive lower interest rates on loans if their network of bank ties has a mix of embedded ties and arm’s-length ties. These network effects arise because embedded ties motivate network partners to share private resources, while arm’s-length ties facilitate access to public information on market prices and loan opportunities so that the benefits of different types of ties are optimized within one network. I con-clude with a discussion of how the value produced by a network is at a pre-mium when it creates a bridge that links the public information of markets with the private resources of relationships. cess and costs in ways that are inadequately incorporated into financial theory (Baker

Web Services (WS) have emerged as a new component-based software develop-ment paradigm in a network-centric environment based on the Service-Oriented Architec-ture (SOA), the XML open standard description language, and HTTP transportation pro-tocol. Legacy software systems can incorporate WS technology in order to be reused and integrated in a distributed environment across heterogeneous platforms. While WS is gaining its momentum toward wide adoption in the software industry, there are two criti-cal issues yet to be addressed before its power is fully realized: (1) the migration of leg-acy distributed software systems toward WS applications and (2) the innovation of new infrastructures and languages in support of WS application development. The contribu-tion of this dissertation is in these two directions. First, a comprehensive, systematic, automatable, and language-neutral approach is presented toward reengineering legacy software systems to WS applications, rather than rewriting the whole legacy software system from scratch in an ad hoc, language-specific manner. It is noteworthy that this approach is not specific to reengineering WS applica-tions but can be generalized to reengineering legacy software systems to other applica-

Positron Emission Tomography (PET) was used to determine regional cerebral blood flow (rCBF) when eight normal right-handed males read and made acceptabil-ity judgments about sentences. rCBF was greater in Broca’s area (particularly in the pars opercularis) when subjects judged the semantic plausibility of syntactically more complex sentences as compared to syntactically less complex sentences. rCBF was greater in left perisylvian language areas when subjects had to decide whether sentences were semantically plausible than when subjects had to decide whether syntactically identical sentences contained a nonsense word. The results of this ex-periment suggest that overall sentence processing occurs in regions of the left peri-sylvian association cortex. The results also provide evidence that one particular aspect of sentence processing (the process that corresponds to the greater difficulty of comprehending center-embedded than right-branching relative clause sentences) is centered in the pars opercularis of Broca’s area. This process is likely to be related to the greater memory load associated with processing center-embedded sen-

p s. the safety of clinical use. In the present study, the contents of six nucleosides (adenosine, cytidine,

This document is an instructional module package prepared in objective formor use by an instructor familiar with"the operation and maintenance of a chemical precipitation softening, system. Included are objectives, instructor guides, student handouts and transparency masters. This is the second level of a three module; series. The module consideis chemical dosages, economical operation,, ti-oub4shooting process problems, and evaluation cf softener design.--(AuthorjRH) 4

Hop-by-hop data aggregation is a very important technique for reducing the communication overhead and energy expenditure of sensor nodes during the process of data collection in a sensor network. However, because individual sensor readings are lost in the per-hop aggregation process, compromised nodes in the network may forge false values as the aggregation results of other nodes, tricking the base station into accepting spurious aggregation results. Here a fundamental challenge is how can the base station obtain a good approximation of the fusion result when a fraction of sensor nodes are compromised? To answer this challenge, we propose SDAP, a Secure Hop-by-hop Data Aggregation Protocol for sensor networks. SDAP is a general-purpose secure data aggregation protocol applicable to multiple aggregation functions. The design of SDAP is based on the principles of divide-andconquer and commit-and-attest. First, SDAP uses a novel probabilistic grouping technique to dynamically partition the nodes in a tree topology into multiple logical groups (subtrees) of similar sizes. A commitment-based hop-by-hop aggregation is performed in each group to generate a group aggregate. The base station then identifies the suspicious groups based on the set of group aggregates. Finally, each group under suspect participates in an attestation process to prove the

The nature of Logical Form is studied through an examination of the syntax and semantics of a range of constructions in Chinese that pertain to scope phenomena, anaphora, and the syntax of empty categories. At the descriptive level, we provide an extensive account of Chinese quantificational sentences, wh questions, A-not-A questions and cleft sentences. Several aspectS-of anaphora are also discu~sed. At the theoretical level, we consider what the observed facts would mean for an optimal theory of Universal Grammar (UG) and linguistic typology. An important intuition captured in traditional treatments of scope phenomena is that the surface order among quantifiers corresponds directly to their scope order in LF. A direct formulation of this idea as a principle f)f scope assignment, however, has been fouild to be in-