An Analysis of Neurogenesis in a Mouse Model of Chemotherapy Related Cognitive Impairment

Cancer patients treated with adjuvant chemotherapy often experience cognitive decline following treatment. This phenomenon, often dubbed “chemo brain” or “chemo fog” is usually temporary, but for a subset of survivors, these cognitive impairments can be long-lasting (\u3e10 years) and negatively affect patients’ quality of life, career performance, and social fulfillment. While it is unclear what neurobiological mechanisms underlie chemotherapy related cognitive impairment, the majority of the animal literature has focused on adult neurogenesis. One process important for neurogenesis is the proliferation of new neurons within the dentate gyrus of the hippocampus. It is evident that many chemotherapy agents can negatively impact levels of neurogenesis shortly after treatment. However, only a few studies have investigated the long-term impact of chemotherapy on neurogenesis. The present studies explore the long-term impact of three commonly used chemotherapy agents on neurogenesis utilizing immunohistochemistry in a male C57BL/6J mouse model. EXP 1: The effects of cyclophosphamide or doxorubicin on neuronal proliferation were evaluated at 1 day, 56 days and 6 months post-treatment. Results indicated that neither cyclophosphamide nor doxorubicin treatment altered proliferation rates across either short-term or long-term intervals. EXP 2: The effects of 5-FU (alone or in combination with either the antioxidant melatonin or the antidepressant fluoxetine) on neuronal proliferation were evaluated at 1 day, 56 days and 6 months post-treatment. The results indicated that there was no effect of 5-FU or neuroprotectant treatment at any time point. The current studies suggest that neither cyclophosphamide, doxorubicin, nor 5-FU affect neurogenic proliferation in C57BL/6J mice directly after injection or up to 6 months post injection. As such, impaired neurogenic proliferation is an unlikely cellular mechanism for chemotherapy related cognitive impairment detected within this strain

Deformation Quantization: Quantum Mechanics Lives and Works in Phase-Space

Wigner's quasi-probability distribution function in phase-space is a special (Weyl) representation of the density matrix. It has been useful in describing quantum transport in quantum optics; nuclear physics; decoherence (eg, quantum computing); quantum chaos; "Welcher Weg" discussions; semiclassical limits. It is also of importance in signal processing. Nevertheless, a remarkable aspect of its internal logic, pioneered by Moyal, has only emerged in the last quarter-century: It furnishes a third, alternative, formulation of Quantum Mechanics, independent of the conventional Hilbert Space, or Path Integral formulations. In this logically complete and self-standing formulation, one need not choose sides--coordinate or momentum space. It works in full phase-space, accommodating the uncertainty principle. This is an introductory overview of the formulation with simple illustrations.Comment: LaTeX, 22 pages, 2 figure

The Origin of Xenoliths with Cumulus Textures Found Above the Subsurface Extension of the Stillwater Complex, Montana

The Archean Stillwater Complex is a large layered mafic-ultramafic intrusion (LMI) exposed in the Beartooth Mountains of south-central Montana. Gravity measurements suggest that the north-dipping complex extends under cover at depth. Some of the exposures located above the subsurface Stillwater Complex are younger Cretaceous stocks (Susie Peak and Sliderock Mountain stocks), diorite sills and andesite dikes, exposed north of the complex, passed through area of the gravity anomaly that may be the Stillwater Complex. In the summer of 2013, samples of the stocks and their included xenoliths (foreign rock fragments; commonly metamorphosed to greenschist facies conditions) were collected for study. Xenoliths with textures reminiscent of Stillwater Complex cumulates were chosen for further investigation. The host andesitic rocks containing the xenoliths exhibit porphyritic textures—phenocrysts of plagioclase, amphibole ± biotite occur in a finer-grained groundmass of the same minerals. Electron microprobe analyses of amphibole grains from both the host and xenolith are comparable in composition. Electron microprobe analyses for two samples of coexisting xenolith amphibole (Tschermakitic hornblende, magnesio-hastingsite) and plagioclase (rim An83-91Ab17-9) constrain temperature conditions at various pressures (P at 3, 5, and 6 kb; T = 500-656°C, respectively using Holland and Blundy (1994). These conditions are consistent with amphibolite facies metamorphism. Few xenoliths retain the original igneous mineralogy (with the exception of plagioclase) but one sample contains relict “Stillwater-like” mineralogy (e.g., clinopyroxene) and another contains chromite. Plagioclase and relict clinopyroxene compositions are somewhat comparable to Stillwater mineral compositions. The fact that the xenoliths are now metamorphosed and highly altered suggests that either they were metamorphosed prior to their inclusion in the melt or were metamorphosed or hydrothermally altered as a result of incorporation into the melt

Testing Small CPAS Parachutes Using HIVAS

The High Velocity Airflow System (HIVAS) facility at the Naval Air Warfare Center (NAWC) at China Lake was successfully used as an alternative to flight test to determine parachute drag performance of two small Capsule Parachute Assembly System (CPAS) canopies. A similar parachute with known performance was also tested as a control. Realtime computations of drag coefficient were unrealistically low. This is because HIVAS produces a non-uniform flow which rapidly decays from a high central core flow. Additional calibration runs were performed to characterize this flow assuming radial symmetry from the centerline. The flow field was used to post-process effective flow velocities at each throttle setting and parachute diameter using the definition of the momentum flux factor. Because one parachute had significant oscillations, additional calculations were required to estimate the projected flow at off-axis angles. The resulting drag data from HIVAS compared favorably to previously estimated parachute performance based on scaled data from analogous CPAS parachutes. The data will improve drag area distributions in the next version of the CPAS Model Memo

Riparian bird communities in Portland, Oregon : habitat, urbanization, and spatial scale patterns

Urban ecosystems are characterized by human disturbance and changes in the amount, types, and spatial arrangement of wildlife habitat. The relative importance of habitat and human associated variables to urban birds is unknown. In 1999, I surveyed spring bird and plant communities along 54 perennial streams in the Portland, Oregon metropolitan region. My objectives were to determine (1) what habitat and human-associated variables were related to avian community measures, (2) how far from riparian areas did relationships between avifauna and canopy cover and development extend, and (3) habitat characteristics associated with individual bird species. I used Principal Components Analysis to cluster and reduce the number of explanatory variables, and regressed bird community variables against the resulting principal components. Total and nonnative bird abundance were negatively related to the first principal component, PC 1 (high-scoring PC 1 sites had wide, structurally complex native forests) (r2 = 0.38, P < 0.0001 and r2 = 0.63, P < 0.0001, respectively). Several weak (r2 = 0.17-0.31, P < 0.003) curvilinear relationships emerged between overall and native species richness and diversity versus PC 1. Neotropical migratory bird (NMB) species richness and diversity were negatively related to human development variables, and positively related to native shrubs (adjusted r2 = 0.21 and 0.18, respectively; P < 0.003). I regressed bird community variables against canopy cover and street density for each of ten 50-m buffers around sites, then plotted the model fit (r) against buffer width. Native and nonnative abundance measures were negatively related to canopy cover. Total abundance was best predicted by canopy cover 300-350 m from the stream whereas normative abundance was predicted nearly equally by canopy cover in each buffer. The relationships between total species richness, native species richness, total diversity and native diversity were curvilinearly related to canopy cover, with canopy in the first 50 m appearing most important. Neotropical migratory bird species richness, diversity and abundance were negatively related to street density within 150 m of the stream. Brown-headed Cowbird (Molothrus ater) abundance was increasingly, negatively related to canopy cover as spatial scale increased. I used logistic regression to identify habitat and/or human-associated variables that predicted the occurrence of 32 species. The occurrence of four species (American Crow [Corvus brachyrhynchos], House Finch [Carpodacus mexicanus], Red-breasted Nuthatch [Sitta canadensis], and Vaux's Swift [Chaetura vauxi]) was positively, and five species (Black-headed Grosbeak [Pheucticus melanocephalus], Common Yellowthroat [Geothlypis trichas], Rufous Hummingbird [Selasphorus rufus], Steller's Jay [Cyanocitta setlleri], and Swainson's Thrush [Catharus ustulatus]) negatively related to human-associated variables. My results suggest that increasing urban canopy cover is the most valuable land management action for many breeding bird species. Preserving large undeveloped habitats and controlling urban sprawl may help prevent regional declines of NMB species

Comment on ``Conduction states in oxide perovskites: Three manifestations of Ti3+^{3 +} Jahn-Teller polarons in barium titanate''

In this comment to [S. Lenjer, O. F. Schirmer, H. Hesse, and Th. W. Kool, Phys. Rev. B {\bf 66}, 165106 (2002)] we discuss the electronic structure of oxygen vacancies in perovskites. First principles computations are in favour of rather deep levels in these vacancies, and Lenjer et al suggest that the electrons' interaction energy is negative, but data on electroconductivity are against.Comment: 2 pages, no figure

An Evaluation of Porcine Epidemic Diarrhea Virus Survival in Individual Feed Ingredients in the Presence or Absence of a Liquid Antimicrobial

Background: Contaminated complete feed and porcine plasma are risk factors for PEDV introduction to farms and a liquid antimicrobial has been proven useful for reducing risk. This study provides information on the survivability of PEDV across common swine feed ingredients in the presence or absence of the liquid antimicrobial.Results: Eighteen ingredients commonly included in commercial swine diets were selected, including 3 grain sources (corn, soybean meal (SBM), dried distillers grains with solubles (DDGS)), 5 porcine by-products (spray-dried plasma, purified plasma, intestinal mucosa, meat and bone meal and red blood cells (RBCs)), 3 vitamin/trace mineral (VTM) mixes (sow, nursery, finishing), 2 fat sources (choice white grease and soy oil), 3 synthetic amino acids (lysine HCL, D/L methionine, threonine), as well as limestone and dry choline chloride. Complete feed and stock PEDV served as controls. Thirty grams of each ingredient were inoculated with 2 mL PEDV. A matched set of samples were treated with the formaldehyde-based liquid antimicrobial SalCURB® (LA). All samples (n = 320) were stored outdoors under winter time ambient conditions for 30 days. Samples were submitted on 1, 7, 14 and 30 days post-inoculation (DPI) and tested by PCR and virus isolation (VI). All VI-negative samples were tested by swine bioassay. Viable PEDV was detected by VI or swine bioassay at 1, 7, 14 and 30 DPI from SBM, DDGS, meat & bone meal, RBCs, lysine HCL, D/L methionine, choice white grease, choline chloride, complete feed and stock virus control and at 7 DPI in limestone and at 14 DPI in threonine. Supplementary testing of complete feed and SBM indicated viable virus out to 45 and 180 DPI, respectively. All other samples were negative by VI and bioassay. In contrast, treatment with LA inactivated PEDV across all ingredients on 1 DPI and induced RNA reduction over time.Conclusions: Under the conditions of this study, PEDV viability in feed was influenced by ingredient with extended survival in SBM. Furthermore, LA treatment rendered virus inactive, independent of ingredient type

A dilemma in representing observables in quantum mechanics

There are self-adjoint operators which determine both spectral and semispectral measures. These measures have very different commutativity and covariance properties. This fact poses a serious question on the physical meaning of such a self-adjoint operator and its associated operator measures.Comment: 10 page