Sensor performance analysis

The theory is described and the equations required to design are developed and the performance of electro-optical sensor systems that operate from the visible through the thermal infrared spectral regions are analyzed. Methods to compute essential optical and detector parameters, signal-to-noise ratio, MTF, and figures of merit such as NE delta rho and NE delta T are developed. A set of atmospheric tables are provided to determine scene radiance in the visible spectral region. The Planck function is used to determine radiance in the infrared. The equations developed were incorporated in a spreadsheet so that a wide variety of sensor studies can be rapidly and efficiently conducted

Degeneration and impaired regeneration of gray matter oligodendrocytes in amyotrophic lateral sclerosis.

Oligodendrocytes associate with axons to establish myelin and provide metabolic support to neurons. In the spinal cord of amyotrophic lateral sclerosis (ALS) mice, oligodendrocytes downregulate transporters that transfer glycolytic substrates to neurons and oligodendrocyte progenitors (NG2(+) cells) exhibit enhanced proliferation and differentiation, although the cause of these changes in oligodendroglia is unknown. We found extensive degeneration of gray matter oligodendrocytes in the spinal cord of SOD1 (G93A) ALS mice prior to disease onset. Although new oligodendrocytes were formed, they failed to mature, resulting in progressive demyelination. Oligodendrocyte dysfunction was also prevalent in human ALS, as gray matter demyelination and reactive changes in NG2(+) cells were observed in motor cortex and spinal cord of ALS patients. Selective removal of mutant SOD1 from oligodendroglia substantially delayed disease onset and prolonged survival in ALS mice, suggesting that ALS-linked genes enhance the vulnerability of motor neurons and accelerate disease by directly impairing the function of oligodendrocytes

Diseases of the nERVous system: retrotransposon activity in neurodegenerative disease

Transposable Elements (TEs) are mobile genetic elements whose sequences constitute nearly half of the human genome. Each TE copy can be present in hundreds to thousands of locations within the genome, complicating the genetic and genomic studies of these highly repetitive sequences. The recent development of better tools for evaluating TE derived sequences in genomic studies has enabled an increasing appreciation for the contribution of TEs to human development and disease. While some TEs have contributed novel and beneficial host functions, this review will summarize the evidence for detrimental TE activity in neurodegenerative disorders. Much of the evidence for pathogenicity implicates endogenous retroviruses (ERVs), a subset of TEs that entered the genome by retroviral infections of germline cells in our evolutionary ancestors and have since been passed down as a substantial fraction of the human genome. Human specific ERVs (HERVs) represent some of the youngest ERVs in the genome, and thus are presumed to retain greater function and resultant pathogenic potential

Amici Curiae Brief of the International Municipal Lawyers Association and Legal Scholars in Support of Defendants-Appellees in Portland Pipe Line Corporation, et al. v. City of South Portland, et al.

This brief to the Maine Supreme Judicial Court was filed in support of the City of South Portland by the Amici Curiae, including the International Municipal Lawyers Association and legal scholars, to provide the Court with a background on the role of local governments in land use planning, and to explain why the City of South Portland’s Clear Skies Ordinance falls easily within the City’s authority and was not preempted by state legislation.After studying the potential for bulk loading of crude oil within its boundaries, the City of South Portland concluded that the infrastructure requirements and environmental impacts of the activity posed a threat to public health and welfare and were incompatible with the community’s vision of itself for the future. The City therefore decided to enact the Clear Skies Ordinance, which prohibits the storing and handling of petroleum or petroleum products for the bulk loading of crude oil onto any marine tank vessel in specified zoning districts. Litigation followed, with plaintiffs arguing that the City lacked authority to enact the Ordinance and that, even if it had such authority in the first instance, that authority had been preempted by other state law. Defendants prevailed on summary judgment in the U.S. District Court for the District of Maine, and during the course of an appeal to the United States Court of Appeals for the First Circuit, the Circuit certified several questions to the Maine Supreme Judicial Court. This brief was filed in support of the City with regard to those certified questions.The brief begins by discussing how central the role of local governments is in making land use decisions, emphasizing the highly localized impacts of land use decisions for public health and welfare. It then describes the zoning mechanisms by which local governments exercise their land use power, and discusses why the zoning power is so important for protecting public health and environmental quality, and responding to the changing needs of communities.Next, the brief explains the legal underpinnings of the City of South Portland’s home rule authority. The Constitution of the State of Maine contains a broad grant of home rule authority that is further strengthened by a statutorily imposed rebuttable presumption of validity for exercises of that authority. Local exercises of zoning authority are consistent within this home rule grant, and the brief discusses why the Clear Skies Ordinance falls squarely within the local zoning power. Finally, the brief explains why the Ordinance has not been expressly or impliedly preempted by state law. For all of those reasons, the brief concludes that the City’s enactment of the Ordinance was valid in the first instance and should not be overturned

A prospective study of alcohol consumption and HIV acquisition among injection drug users

Estimate the effect of alcohol consumption on HIV acquisition while appropriately accounting for confounding by time-varying risk factors

Determinants of alcohol consumption in HIV-uninfected injection drug users

We assess the association between time fixed and time varying participant characteristics and subsequent alcohol consumption in 1,968 injection drug users (median age 37 years, 28% female, 90% African-American) followed semi-annually from 1988 to 2008. Median alcohol consumption was seven drinks per week at study entry (first and third quartile: 1, 26) with 36% reporting binge drinking. Alcohol consumption and binge drinking decreased over follow-up. Older individuals and women reported consuming fewer drinks per week. Higher typical alcohol consumption was reported by those participants who reported in the prior six months: non-injection cocaine use, injection drug use, having one or more sex partners, or among men, a same sex partner. Associations were generally similar for drinks per week and binge drinking. This study demonstrates that in a large urban cohort of persons with a history of injection drug use, risky drug use and sexual risk behavior are associated with subsequent alcohol consumption

Sexual behavior research on a Cohort of gay men, 1984–1990: Can we predict how men will respond to interventions?

In 1984, over 1000 gay and bisexual men volunteered to participate in both the Chicago Multicenter AIDS Cohort Study (MACS) and a companion psychosocial study, the Coping and Change Study (CCS). Participants in the semiannual Chicago MACS/CCS evaluations comprise the largest cohort of high-risk men under continuous medical, behavioral, and psychosocial observation. Chicago MACS/CCS researchers prospectively chart the sexual behavior change patterns of the cohort and relate those behavioral changes to psychosocial correlates and actual HIV infection risk. This report summarizes the behavioral natural history of the Chicago MACS/CCS cohort from 1984 to 1990, focusing on receptive anal sex practices and use patterns for alcohol and the most frequently used recreational drugs. As these are prospective observational and not controlled intervention studies, psychosocial correlates of sexual behavior change by members of the cohort are suggestive of factors influencing behavior change rather than indicative of causal relationships. However, the voluntary availability to participants in the Chicago MACS/CCS of HIV-1 antibody test results beginning in late 1985 provided the opportunity to examine whether demographic, psychosocial, or behavioral factors were indicators of sexual behavior change following disclosure and counseling about HIV-1 serostatus. Recommendations for promotion and maintenance of safer sexual behavior for the long run, and limitations in the generalizability of these findings to the much more diverse populations of men who have sex with other men conclude this article.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44099/1/10508_2005_Article_BF01541496.pd

Modulation of Mrp1 (ABCc1) and Pgp (ABCb1) by Bilirubin at the Blood-CSF and Blood-Brain Barriers in the Gunn Rat

Accumulation of unconjugated bilirubin (UCB) in the brain causes bilirubin encephalopathy. Pgp (ABCb1) and Mrp1 (ABCc1), highly expressed in the blood-brain barrier (BBB) and blood-cerebrospinal fluid barrier (BCSFB) respectively, may modulate the accumulation of UCB in brain. We examined the effect of prolonged exposure to elevated concentrations of UCB on expression of the two transporters in homozygous, jaundiced (jj) Gunn rats compared to heterozygous, not jaundiced (Jj) littermates at different developmental stages (2, 9, 17 and 60 days after birth). BBB Pgp protein expression was low in both jj and Jj pups at 9 days (about 16–27% of adult values), despite the up-regulation in jj animals (2 and 1.3 fold higher than age matched Jj animals at P9 and P17–P60, respectively); Mrp1 protein expression was barely detectable. Conversely, at the BCSFB Mrp1 protein expression was rather high (60–70% of the adult values) in both jj and Jj at P2, but was markedly (50%) down-regulated in jj pups starting at P9, particularly in the 4th ventricle choroid plexuses: Pgp was almost undetectable. The Mrp1 protein down regulation was accompanied by a modest up-regulation of mRNA, suggesting a translational rather than a transcriptional inhibition. In vitro exposure of choroid plexus epithelial cells obtained from normal rats to UCB, also resulted in a down-regulation of Mrp1 protein. These data suggest that down-regulation of Mrp1 protein at the BSCFB, resulting from a direct effect of UCB on epithelial cells, may impact the Mrp1-mediated neuroprotective functions of the blood-cerebrospinal fluid barrier and actually potentiate UCB neurotoxicity

Functional Induction of the Cystine-Glutamate Exchanger System Xc- Activity in SH-SY5Y Cells by Unconjugated Bilirubin

We have previously reported that exposure of SH-SY5Y neuroblastoma cells to unconjugated bilirubin (UCB) resulted in a marked up-regulation of the mRNA encoding for the Na+ -independent cystine∶glutamate exchanger System Xc− (SLC7A11 and SLC3A2 genes). In this study we demonstrate that SH-SY5Y cells treated with UCB showed a higher cystine uptake due to a significant and specific increase in the activity of System Xc−, without the contribution of the others two cystine transporters (XAG− and GGT) reported in neurons. The total intracellular glutathione content was 2 folds higher in the cells exposed to bilirubin as compared to controls, suggesting that the internalized cystine is used for gluthathione synthesis. Interestingly, these cells were significantly less sensitive to an oxidative insult induced by hydrogen peroxide. If System Xc− is silenced the protection is lost. In conclusion, these results suggest that bilirubin can modulate the gluthathione levels in neuroblastoma cells through the induction of the System Xc−, and this renders the cell less prone to oxidative damage