Nuclear applications in manned space station

The zirconium hydride reactor, coupled to a thermo-electric or Brayton conversion system, and the Pu 238 isotope/Brayton system, are considered to be the viable nuclear candidates for the modular space station electrical power system. The basic integration aspects of these nuclear electrical power systems are reviewed, including unique requirements imposed by the buildup and incremental utilization considerations of the modular station. Also treated are the various programmatic aspects of nuclear power system design and selection

EVALUATION OF HEMATOLOGICAL AND SERUM BIOCHEMICAL PROFILES ASSOCIATED WITH THE SUPPLEMENTATION OF ZILPATEROL HYDROCHLORIDE TO FEEDLOT HEIFERS

Supplementation of zilpaterol hydrochloride (ZH; Zilmax®) to cattle has been suggested to have a negative impact on well-being of cattle. The objective of this study was to evaluate the hematological and serum biochemical profiles in feedlot heifers supplemented with ZH in a minimal stress environment. Heifers were randomly assigned to one of two treatment groups: Control (CON no ZH), or ZH (supplemented with ZH at 8.33mg/kg of feed on a DM basis). The study was conducted over a period of 25 d (-2 to 23), with three serum collection periods [-2 to 4 d (ZH supplementation began on d 0); 13-16 d; and 21 to 23 d (withdrawal period)]. Serum samples were collected for a large animal chemistry profile analysis and blood samples were collected for hematological profile analysis. Liver, longissimus dorsi (LM), and biceps femoris (BF) samples were collected for vitamin E concentration analysis. There was a treatment effect for serum calcium (P = 0.008) with concentrations being greater in CON. A treatment effect was observed for serum bicarbonate (P = 0.03), with ZH having greater concentrations. A treatment x time interaction was observed for glucose (P = 0.02), BUN (P \u3c 0.001), Cl (P = 0.04), creatinine (P ≤ 0.001), and creatine kinase (P≤ 0.001). In heifers fed ZH, creatinine, creatine kinase, and Cl concentrations in the serum were greater than CON heifers whereas glucose and BUN concentrations were decreased in the ZH heifers. There was a treatment x time interaction for alkaline phosphatase (ALP, P \u3c 0.001) and gamma-glutamyltransferase (GGT, P = 0.004). Overall, concentrations of ALP and GGT were greater in CON heifers. In the hematological profile, there was a treatment effect (P = 0.02) for hematocrit, where the ZH heifers had greater hematocrit. These data suggest that in this controlled environment, there were no negative impacts observed on the homeostasis with supplementation of ZH and most variables were within the normal homeostatic range of feedlot cattle. Advisor: Steven J. Jone

EVALUATION OF HEMATOLOGICAL AND SERUM BIOCHEMICAL PROFILES ASSOCIATED WITH THE SUPPLEMENTATION OF ZILPATEROL HYDROCHLORIDE TO FEEDLOT HEIFERS

Supplementation of zilpaterol hydrochloride (ZH; Zilmax®) to cattle has been suggested to have a negative impact on well-being of cattle. The objective of this study was to evaluate the hematological and serum biochemical profiles in feedlot heifers supplemented with ZH in a minimal stress environment. Heifers were randomly assigned to one of two treatment groups: Control (CON no ZH), or ZH (supplemented with ZH at 8.33mg/kg of feed on a DM basis). The study was conducted over a period of 25 d (-2 to 23), with three serum collection periods [-2 to 4 d (ZH supplementation began on d 0); 13-16 d; and 21 to 23 d (withdrawal period)]. Serum samples were collected for a large animal chemistry profile analysis and blood samples were collected for hematological profile analysis. Liver, longissimus dorsi (LM), and biceps femoris (BF) samples were collected for vitamin E concentration analysis. There was a treatment effect for serum calcium (P = 0.008) with concentrations being greater in CON. A treatment effect was observed for serum bicarbonate (P = 0.03), with ZH having greater concentrations. A treatment x time interaction was observed for glucose (P = 0.02), BUN (P \u3c 0.001), Cl (P = 0.04), creatinine (P ≤ 0.001), and creatine kinase (P≤ 0.001). In heifers fed ZH, creatinine, creatine kinase, and Cl concentrations in the serum were greater than CON heifers whereas glucose and BUN concentrations were decreased in the ZH heifers. There was a treatment x time interaction for alkaline phosphatase (ALP, P \u3c 0.001) and gamma-glutamyltransferase (GGT, P = 0.004). Overall, concentrations of ALP and GGT were greater in CON heifers. In the hematological profile, there was a treatment effect (P = 0.02) for hematocrit, where the ZH heifers had greater hematocrit. These data suggest that in this controlled environment, there were no negative impacts observed on the homeostasis with supplementation of ZH and most variables were within the normal homeostatic range of feedlot cattle. Advisor: Steven J. Jone

Assessment of BoviPureTM for the In Vitro Production of Bovine Embryos

The objective of this study was to examine the potential utility of a commercially available sperm separation and purification product for the in vitro production of bovine embryos. Bovine oocytes were purchased from a commercial supplier, and matured oocytes were randomly allocated to one of two treatments. Oocytes were co-incubated with frozen-thawed semen washed twice with BoviPureTM (BoviPure group) or with modified Brackett-Oliphant medium (control group). After a 6-hour insemination period, oocytes were cultured in vitro for 8 days. Cleavage rate of embryos was determined 48 hours post-insemination, and blastocyst formation rate was assessed on day 8 of culture. The experiment was replicated three times, and data were analyzed using chi-square analysis. Washing of sperm in BoviPureTM had no effect (P\u3e.05) on either cleavage rate (77.2%) or blastocyst development (21.6%) when compared with controls (71.9% and 17.1%, respectively). These results indicate that, under conditions of our study, the washing of sperm with BoviPureTM did not significantly enhance the ability to produce bovine embryos in vitro

Klonale experimentelle autoimmune Enzephalomyelitis: Charakterisierung myelinspezifischer Antikörper in einem TH2-induzierten adoptiven Transfermodell

Die Multiple Sklerose ist in Europa und Nordamerika die häufigste Entmarkungserkrankung des zentralen Nervensystems. Sie ist neben Inflammation und Demyelinisierung auch durch neurodegenerative Prozesse gekennzeichnet. Hierbei spielen T-Zell-vermittelte Mechanismen eine wesentliche Rolle. Aufgrund der Heterogenität ihres klinischen Verlaufs sind weder individuelle Voraussagen bezüglich der Progression der neurologischen Defizite noch bezüglich des therapeutischen Ansprechens möglich. Diese klinische Heterogenität spiegelt sich in unterschiedlichen histopathologischen sowie liquorzytologischen Mustern wieder. Es finden sich Subtypen, bei denen humorale Effektormechanismen eine wesentliche Rolle zu spielen scheinen. Die experimentelle autoimmune Enzephalomyelitis (EAE) ist ein Tiermodell der Multiplen Sklerose und kann in suszeptiblen Tierstämmen durch aktive Immunisierung mit Myelinpeptiden oder durch den adoptiven Transfer myelinspezifischer CD4 positiver TH1-Zellen induziert werden. Die EAE galt lange als eine im Wesentlichen TH1-vermittelte Erkrankung, während TH2-Zellen eher protektive Funktionen zugeschrieben wurden. Dieses TH1-TH2-Paradigma stellt jedoch eine zu starke Vereinfachung der Immunantwort im Rahmen der EAE-Induktion dar. Zum einen spielen weitere T-Zell-Subpopulationen eine wesentliche Rolle bei der Pathogenese. So gelingt z.B. durch den adoptiven Transfer von TH17-Zellen eine sehr effiziente EAE-Induktion auch ohne eine vorherige in vitro Stimulation. Zum anderen kann in einem neuartigen adoptiven T-Zell-Transfermodell durch den Transfer klonaler Proteolipidprotein (PLP) 139-151 spezifischer CD4+ TH2-Zellen bei immunkompetenten SJL-Mäusen eine EAE mit chronifizierendem Verlauf induziert werden, deren entzündliche Läsionen in der chronischen Phase durch Infiltrate aus Makrophagen, B-Zellen, Plasmazellen sowie massiven Antikörperablagerungen gekennzeichnet sind. Im Serum der Mäuse ist eine hochtitrige Antikörperantwort gegen PLP139-51 nachweisbar. Ziel der vorliegenden Arbeit ist eine nähere Charakterisierung der Antikörperantwort in diesem Modell. Nach EAE-Induktion durch adoptiven Transfer von Zellen des PLP 139-151 spezifischen TH2-Zell-Klons 3-3 wurden in der chronischen Phase der Erkrankung Milzzellen entnommen und mit Zellen der Sp2-Maus-Myelom-Zelllinie fusioniert. Hierdurch wurden antikörperproduzierende Hybridomzellen generiert. Durch Klonierung mittels des Limiting-Dilution-Verfahrens und anschließender chromatograpischer Aufreinigung wurden monoklonale, myelinspezifische Antikörper gewonnen. Deren weitere Charakterisierung erfolgte mittels ELISA, Western-Blot, an Gewebsschnitten sowie in adoptiven Transferexperimenten. Die Besonderheit dieses Modells liegt darin, dass die monoklonalen Antikörper ohne vorherige aktive Immunisierung generiert wurden. Es handelt sich somit um einen neuen, physiologischeren Ansatz zur Charakterisierung der T-Zell-B-Zell-Interaktion bzw. der Rolle von Antikörpern in einem neuen TH2-induzierten EAE-Modell. Im ersten Teil der Arbeit wurden ausgewählte monoklonale PLP139-151 spezifische Antikörper der Isotypen IgG1 sowie IgG2b aufgereinigt. Zwar konnten diese PLP139-151 in einem ELISA binden. Weder in einem Western Blot mit Myelinproteinen noch in Kryo- oder Paraffinschnitten von ZNS-Gewebe zeigte sich hingegen eine spezifische Bindung an Myelin. Der adoptive Transfer in mit Pertussis Toxin vorbehandelte SJL-Mäuse konnte keine klinischen Symptome induzieren. Im zweiten Teil der Arbeit wurden die Untersuchungen daher auf Antikörper gegen weitere Myelinpeptide ausgedehnt. Hierbei konnte der Myelin Oligodendrozyten Glykoprotein (MOG) 35-55 spezifische monoklonale IgM Antikörper 4E6-2 identifiziert werden, der Myelin in Paraffinschnitten spezifisch färbte. Zudem zeigte sich im Western Blot eine Bindung an MOG. Der Antikörper wurde in einem Transferversuch an Mäusen getestet, bei denen zuvor eine EAE durch adoptiven Transfer eines TH1-Klons induziert worden war. Hierbei fand sich kein Hinweis auf eine krankheitsmodifizierende Wirkung des Antikörpers. Zur weiteren Klärung der Rolle antikörpervermittelter Mechanismen im hier beschriebenen Modell ist eine weitere Charakterisierung der Antikörper hinsichtlich ihrer Effektorfunktionen, wie z.B. ihrer Fähigkeit zur Komplementaktivierung, erforderlich

Inter‐ and intra‐software reproducibility of computed tomography lung density measurements

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/156221/2/mp14130.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156221/1/mp14130_am.pd

Radiomics of Lung Nodules: A Multi-Institutional Study of Robustness and Agreement of Quantitative Imaging Features.

Radiomics is to provide quantitative descriptors of normal and abnormal tissues during classification and prediction tasks in radiology and oncology. Quantitative Imaging Network members are developing radiomic "feature" sets to characterize tumors, in general, the size, shape, texture, intensity, margin, and other aspects of the imaging features of nodules and lesions. Efforts are ongoing for developing an ontology to describe radiomic features for lung nodules, with the main classes consisting of size, local and global shape descriptors, margin, intensity, and texture-based features, which are based on wavelets, Laplacian of Gaussians, Law's features, gray-level co-occurrence matrices, and run-length features. The purpose of this study is to investigate the sensitivity of quantitative descriptors of pulmonary nodules to segmentations and to illustrate comparisons across different feature types and features computed by different implementations of feature extraction algorithms. We calculated the concordance correlation coefficients of the features as a measure of their stability with the underlying segmentation; 68% of the 830 features in this study had a concordance CC of ≥0.75. Pairwise correlation coefficients between pairs of features were used to uncover associations between features, particularly as measured by different participants. A graphical model approach was used to enumerate the number of uncorrelated feature groups at given thresholds of correlation. At a threshold of 0.75 and 0.95, there were 75 and 246 subgroups, respectively, providing a measure for the features' redundancy

Mechanical rotational thrombectomy in long femoropopliteal artery and bypass occlusions: risk factors for periprocedural peripheral embolization

PURPOSEWe aimed to examine lesion characteristics influencing technical outcome and periprocedural peripheral embolization (PPE) during percutaneous mechanical rotational thrombectomy (PMT) of long femoropopliteal artery and bypass occlusions.METHODSRetrospectively, 65 consecutive patients (43 male patients, mean age 70±12 years; Rutherford category I–III), undergoing PMT (Rotarex®, Straub Medical AG) with acutely/subacutely occluded femoropopliteal arteries/bypasses were included. Occlusions (mean length, 217±98 mm) were treated by PMT followed by percutaneous transluminal angioplasty (PTA) plus drug-coated balloon or PTA plus stenting/stentgrafting. Technical success was defined as residual stenosis 200 mm (15%; 6/39; OR 4.5; 95% CI, 0.5–40; p = 0.014) and thrombus density ≤45 HU (20%; 2/10; OR 3.0; 95% CI, 0.2–38.9; p = 0.05). No significant relation between risk factors and technical success was found.CONCLUSIONPMT followed by PTA or implantation of stent (grafts) appears to be effective and safe for revascularization of acute/subacute long occlusions. Thrombus density <45 HU and lesion length above 20 cm represent risk factors for PPE during PMT

A controlled statistical study to assess measurement variability as a function of test object position and configuration for automated surveillance in a multicenter longitudinal COPD study (SPIROMICS)

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134827/1/mp7303.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/134827/2/mp7303_am.pd