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31.
Hydrogel particles are versatile materials that provide exquisite, tunable control over the sequestration and delivery of materials in pharmaceutics, tissue engineering, and photonics. The favorable properties of hydrogel particles depend largely on their size, and particles ranging from nanometers to micrometers are used in different applications. Previous studies have only successfully fabricated these particles in one specific size regime and required a variety of materials and fabrication methods. A simple yet powerful system is developed to easily tune the size of polypeptide‐based, thermoresponsive hydrogel particles, from the nano‐ to microscale, using a single starting material. Particle size is controlled by the self‐assembly and unique phase transition behavior of elastin‐like polypeptides in bulk and within microfluidic‐generated droplets. These particles are then stabilized through ultraviolet irradiation of a photo‐crosslinkable unnatural amino acid (UAA) cotranslationally incorporated into the parent polypeptide. The thermoresponsive property of these particles provides an active mechanism for actuation and a dynamic responsive to the environment. This work represents a fundamental advance in the generation of crosslinked biomaterials, especially in the form of soft matter colloids, and is one of the first demonstrations of successful use of UAAs in generating a novel material.  相似文献   
32.
Unit testing plays a major role in the software development process. What started as an ad hoc approach is becoming a common practice among developers. It enables the immediate detection of bugs introduced into a unit whenever code changes occur. Hence, unit tests provide a safety net of regression tests and validation tests which encourage developers to refactor existing code with greater confidence. One of the major corner stones of the agile development approach is unit testing. Agile methods require all software classes to have unit tests that can be executed by an automated unit-testing framework. However, not all software systems have unit tests. When changes to such software are needed, writing unit tests from scratch, which is hard and tedious, might not be cost effective. In this paper we propose a technique which automatically generates unit tests for software that does not have such tests. We have implemented GenUTest, a prototype tool which captures and logs interobject interactions occurring during the execution of Java programs, using the aspect-oriented language AspectJ. These interactions are used to generate JUnit tests. They also serve in generating mock aspects—mock object-like entities, which enable testing units in isolation. The generated JUnit tests and mock aspects are independent of the tool, and can be used by developers to perform unit tests on the software. Comprehensiveness of the unit tests depends on the software execution. We applied GenUTest to several open source projects such as NanoXML and JODE. We present the results, explain the limitations of the tool, and point out direction to future work to improve the code coverage provided by GenUTest and its scalability.  相似文献   
33.
Le fait de devoir fournir des Iogements aux vagues d'immigrants a amélioré ces derniers temps les possibilités d'Israël en matière de construction, particulièrement parce que bon nombre de ces immigrants venant de pays riches exigeait un standing élevé.

Dans ce rapport préparé pour I'AEAI (Association des ingénieurs et architectes en Israël) on explique la façon dont on a résolu le problème.  相似文献   
34.
SPARC (Secreted Protein Acidic and Rich in Cysteine) regulates the transendothelial flux of macromolecules through a paracellular pathway. We now have demonstrated that SPARC-induced increments in albumin flux across postconfluent endothelial cell (EC) monolayers are mediated, in part, through protein tyrosine phosphorylation. SPARC increased tyrosine phosphorylation of EC proteins up to 12-fold within 1 h. The phosphotyrosine-containing proteins were immunolocalized to the intercellular boundaries. Two substrates for SPARC-induced tyrosine phosphorylation were identified as beta-catenin and paxillin. Inhibition of tyrosine kinases with herbimycin A or genistein reversed the barrier dysfunction induced by SPARC by 71% and 49%, respectively. Herbimycin A also protected against SPARC-induced intercellular gap formation. In contrast, inhibition of tyrosine phosphatases with sodium orthovanadate or phenylarsine oxide enhanced the loss of barrier function associated with SPARC treatment by 120% and 88%, respectively. These data indicate that SPARC influences EC-EC interactions through a tyrosine phosphorylation-dependent signaling pathway.  相似文献   
35.
What inhibits parents from seeking psychological help for their children? This study examined the attitudes of mothers of school-age children toward seeking psychological help from school psychological services and from private psychologists. Mothers express greater and more intense worries in relation to seeking help from school psychological services as compared to private psychologists. Hypothetical vignettes about a problematic child also showed that mothers prefer to refer both their own child and that of a friend to a private psychologist. Reducing the threat aroused by public sector psychologists should increase the utilization of psychological help for children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
36.
The bcl-2 proto-oncogene encodes a protein that blocks programmed cell death (apoptosis). Although bcl-2 has been shown to be involved in the development of follicular lymphoma via a chromosomal translocation t(14;18), little is known about its function in non-hematolymphoid neoplasms. The bcl-2 protein is normally expressed in the regenerative crypt compartment of the colon, small intestine, and stomach, and has been found to be abnormally overexpressed as an early event in the dysplasia-carcinoma sequences of both ulcerative colitis-related and gastric neoplasias. This study was undertaken to evaluate the role of bcl-2 in the Barrett's metaplasia-dysplasia-carcinoma sequence. Thirty-six esophageal resection specimens were studied, using a monoclonal antibody to the bcl-2 protein on fixed paraffin-embedded specimens. Barrett's mucosa was present in each specimen: low-grade dysplasia in 35, high-grade dysplasia in 34, intramucosal carcinoma (IMC) in 23, and submucosal carcinoma in 13. In addition, a section of the gastric resection margin was evaluated for bcl-2 immunoreactivity in each case. In all cases, the regenerative compartment of the gastric mucosa in the resection margins stained for bcl-2; however, no immunoreactivity was seen in any of the cases of Barrett's mucosa with or without dysplasia or carcinoma. We conclude that, in contrast to its role in gastric neoplasia, bcl-2 alterations are not an important molecular marker in the neoplastic progression of Barrett's mucosa.  相似文献   
37.
The role of the renin-angiotensin system (RAS) in the control of blood pressure and drinking was investigated in fresh water (FW)- and seawater (SW)-adapted eels, Anguilla anguilla, by comparing the effects of pharmacological manipulation through the use of papaverine (stimulator) and captopril (inhibitor) on the endogenous system. In SW eels basal blood pressure levels were lower (23.3 +/- 0.8 mm Hg) with correspondingly higher basal drinking rates (0.51 +/- 0.07 ml/kg/hr) and plasma AII concentrations (32.89 +/- 4.19 fmol/ml) compared to FW eels (33.8 +/- 1.3 mm Hg, 0.06 +/- 0.02 ml/kg/hr, 9.72 +/- 0.60 fmol/ml, respectively). In FW eels papaverine caused immediate hypotension with full recovery, decrease in plasma osmolality, and increase in drinking rate and plasma AII concentration, but in SW eels, hypotension with full recovery and an increase in plasma osmolality, drinking rate, and plasma AII concentration occurred. In FW eels captopril had no effect on the parameters measured, but in SW eels it caused a sustained decrease in blood pressure and a decline in the basal drinking rate and plasma AII concentration. Papaverine was also administered 15 min after captopril. In FW eels this manipulation caused hypotension only after the papaverine injection, followed by a partial recovery. Osmolality was unaffected, the previously observed papaverine-induced dipsogenic response was blocked, and the rise in plasma AII concentrations was smaller than with papaverine only. In SW eels there was an immediate hypotension after captopril administration with full recovery.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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