Bisporangiate Inflorescences in Pseudotsuga

Author Institution: New York Conservation Department, Albany, N. Y

Cell cycle length, cell size, and proliferation rate in hydra stem cells

We have analyzed the cell cycle parameters of interstitial cells in Hydra oligactis. Three subpopulations of cells with short, medium, and long cell cycles were identified. Short-cycle cells are stem cells; medium-cycle cells are precursors to nematocyte differentiation; long-cycle cells are precursors to gamete differentiation. We have also determined the effect of different cell densities on the population doubling time, cell cycle length, and cell size of interstitial cells. Our results indicate that decreasing the interstitial cell density from 0.35 to 0.1 interstitial cells/epithelial cell (1) shortens the population doubling time from 4 to 1.8 days, (2) increases the [3H]thymidine labeling index from 0.5 to 0.75 and shifts the nuclear DNA distribution from G2 to S phase cells, and (3) decreases the length of G2 in stem cells from 6 to 3 hr. The shortened cell cycle is correlated with a significant decrease in the size of interstitial stem cells. Coincident with the shortened cell cycle and increased growth rate there is an increase in stem cell self-renewal and a decrease in stem cell differentiation

Using AI/expert system technology to automate planning and replanning for the HST servicing missions

This paper describes a knowledge-based system that has been developed to automate planning and scheduling for the Hubble Space Telescope (HST) Servicing Missions. This new system is the Servicing Mission Planning and Replanning Tool (SM/PART). SM/PART has been delivered to the HST Flight Operations Team (FOT) at Goddard Space Flight Center (GSFC) where it is being used to build integrated time lines and command plans to control the activities of the HST, Shuttle, Crew and ground systems for the next HST Servicing Mission. SM/PART reuses and extends AI/expert system technology from Interactive Experimenter Planning System (IEPS) systems to build or rebuild time lines and command plans more rapidly than was possible for previous missions where they were built manually. This capability provides an important safety factor for the HST, Shuttle and Crew in case unexpected events occur during the mission

An evaluation of the archaeological potential of Riverfront Park in Corvallis, Oregon

The archaeological resources contained in Corvallis Riverfront Commemorative Park (RCP) have a great potential to add to the historical record of the warehouse district of the original town of Marysville (Corvallis). The City of Corvallis' proposed Combined Sewer Overflow (CSO) project and proposed changes to Riverfront Commemorative Park threaten to destroy archaeological resources within the research area. The purpose of this research was to assess the archaeological potential of the research area between VanBuren and Jefferson Avenues along the Willamette River. The assessment was based on an archaeological survey and historical documents. Historical records and maps were used to create a chronology of the developments which occurred within the research area. By knowing who occupied the riverfront and when, archaeologists can design a plan for the excavation of these resources. The archaeological survey was conducted to locate remains that may be related to structures that once occupied the riverfront. Maps of the City's proposed construction were used to determine the potential resources that will be impacted. The historical record indicated that there is a great potential for the research area to yield archaeological remains which can add to our knowledge about the formation of Marysville (Corvallis). These archaeological remains if properly excavated could be used for public interpretation and as a common theme within Riverfront Commemorative Park. An assessment of construction project maps for the CSO project and proposed changes to Riverfront Commemorative Park indicate that a majority of the archaeological resources contained within the research area will be destroyed. Based on these assessments it is recommended that the City of Corvallis conduct subsurface archaeological testing to recover as much information related to the settlement of the research area as possible

Food Inflation in Pope County

Although inflation is cooling off in many sectors of the US economy, food inflation continues to surge, indicating the volatility of the agri-food system. The higher food prices make it difficult for US consumers to afford everyday essential food products. The main objective of this research is to calculate food inflation in the pope county area. We utilized the consumer price index (CPI) to measure the change in prices paid by pope county consumers for food. Our preliminary analyses show that food prices in pope county are easing. Specifically, the food inflation rate in pope county declined in March 2023 compared to January 2023

Development of fluorescent sensors for the detection of hydrophobic amines and glycolipids

Field of study: Chemistry.Dr. Timothy E. Glass, Dissertation Supervisor.Includes vita."December 2017."A novel fluorescent sensor was designed and synthesized to detect hydrophobic amines and was used to extract them from synthetically prepared vesicles. This sensor had a higher affinity for diamines than primary amines, providing a fluorescence decrease upon binding both analytes. This sensor bound longer chain amines such as decylamine and 1,10-diaminodecane, better than shorter chain amines such as octylamine. This binding is influenced by both hydrophobic effects and electrostatic interactions between the sensor and analyte, driven by the hydrophobic cavity on the sensor. The sensor also unexpectedly binds to spermine and spermidine, however, with an increase in fluorescence. The mechanism for this phenomenon is not yet understood. The sensor showed it is possible to remove hydrophobic amines from synthetic veiscles, which can be applied to biological systems. A fluorescent sensor for glycolipids was also attempted to be synthesized by several different methods, incurring a new synthesis through redesigning the synthesis. Each method provided undesired products, decomposition, or no reactivity. Initial redesigns were due to complications in solubility of the carbazole aldehyde. Elongating the ester chain enhanced the solubility, but it remained unreactive towards any of the attempted reactions. This redesigned the sensor with a protected acid group that has been tested towards amide bond formation reactions to install the boronic acid or a haloarene, which will then undergo a Miyaura Borylation to install the boronic acid. If this does not prove successful, it will require alternative synthetic methods to install the boronic acid.Includes bibliographical references (pages 143-153)

Object recognition and pose estimation of planar objects from range data

The Extravehicular Activity Helper/Retriever (EVAHR) is a robotic device currently under development at the NASA Johnson Space Center that is designed to fetch objects or to assist in retrieving an astronaut who may have become inadvertently de-tethered. The EVAHR will be required to exhibit a high degree of intelligent autonomous operation and will base much of its reasoning upon information obtained from one or more three-dimensional sensors that it will carry and control. At the highest level of visual cognition and reasoning, the EVAHR will be required to detect objects, recognize them, and estimate their spatial orientation and location. The recognition phase and estimation of spatial pose will depend on the ability of the vision system to reliably extract geometric features of the objects such as whether the surface topologies observed are planar or curved and the spatial relationships between the component surfaces. In order to achieve these tasks, three-dimensional sensing of the operational environment and objects in the environment will therefore be essential. One of the sensors being considered to provide image data for object recognition and pose estimation is a phase-shift laser scanner. The characteristics of the data provided by this scanner have been studied and algorithms have been developed for segmenting range images into planar surfaces, extracting basic features such as surface area, and recognizing the object based on the characteristics of extracted features. Also, an approach has been developed for estimating the spatial orientation and location of the recognized object based on orientations of extracted planes and their intersection points. This paper presents some of the algorithms that have been developed for the purpose of recognizing and estimating the pose of objects as viewed by the laser scanner, and characterizes the desirability and utility of these algorithms within the context of the scanner itself, considering data quality and noise

Mutagen-induced diploid human lymphoblast variants containing altered hypoxanthine guanine phosphoribosyl transferase

The human lymphoblast line MGL8 was treated with HAT and subsequently “mutagenized” with EMS (200 μg/ml) to give 15% survival, and 6-thioguanine-resistant cells were selected by cloning in soft agarose containing the drug (1 μg/ml). Eighteen sublines of independently derived resistant clones were isolated and studied in detail. One subline had a low residual HGPRT activity of about 1% of the parental cells. The HGPRT of this subline had a higher K m for PRPP, was more sensitive to heat, and was degraded faster by trypsin than the enzyme in extracts of MGL8 cells. This resistant subline and three others contained CRM levels of 1-38%, compared to the wild-type, so they probably represent true structural mutants of the HGPRT gene. All the variants maintained the karyotype of the parental line (46, XY, 6p − ).Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45551/1/11188_2005_Article_BF01551810.pd