Distress to Structures on Loose Ash and Cinder Fills

The Logan Section of the City of Philadelphia, that encompasses 17 city blocks and includes 997 row type dwellings, was constructed in the early 1900s. It is reported that settlement of these structures has continued since their construction. In 1986, a Geotechnical Investigation, commissioned by the City of Philadelphia, revealed that a total of two to three feet of settlement, with as much as one to two feet of differential settlement, has taken place. Recent measurements indicated that settlement is still in progress. This settlement has resulted in severe structural damage and, in some cases, collapse of the buildings. One hundred (100) homes have been declared imminently dangerous, 110 homes have been declared dangerous, and the remaining homes are considered moderately damaged. This paper discusses the probable causes of settlement, and evaluates the geotechnical characteristics and properties of the ash and cinders. These characteristics are considered the prime cause of the problem at the Logan Section

Retrograde transport of cholera toxin from the plasma membrane to the endoplasmic reticulum requires the trans-Golgi network but not the Golgi apparatus in Exo2-treated cells

Cholera toxin (CT) follows a glycolipid-dependent entry pathway from the plasma membrane through the trans-Golgi network (TGN) to the endoplasmic reticulum (ER) where it is retro-translocated into the cytosol to induce toxicity. Whether access to the Golgi apparatus is necessary for transport to the ER is not known. Exo2 is a small chemical that rapidly blocks anterograde traffic from the ER to the Golgi and selectively disrupts the Golgi apparatus but not the TGN. Here we use Exo2 to determine the role of the Golgi apparatus in CT trafficking. We find that under the condition of complete Golgi ablation by Exo2, CT reaches the TGN and moves efficiently into the ER without loss in toxicity. We propose that even in the absence of Exo2 the glycolipid pathway that carries the toxin from plasma membrane into the ER bypasses the Golgi apparatus entirely