DSN G/T(sub op) and telecommunications system performance

Provided here is an intersystem comparison of present and evolving Deep Space Network (DSN) microwave receiving systems. Comparisons of the receiving systems are based on the widely used G/T sub op figure of merit, which is defined as antenna gain divided by operating system noise temperature. In 10 years, it is expected that the DSN 32 GHz microwave receiving system will improve the G/T sub op performance over the current 8.4 GHz system by 8.3 dB. To compare future telecommunications system end-to-end performance, both the receiving systems' G/T sub op and spacecraft transmit parameters are used. Improving the 32 GHz spacecraft transmitter system is shown to increase the end-to-end telecommunications system performance an additional 3.2 dB, for a net improvement of 11.5 dB. These values are without a planet in the field of view (FOV). A Saturn mission is used for an example calculation to indicate the degradation in performance with a planet in the field of view

Variola minor in coalfield areas of England and Wales, 1921–34: geographical determinants of a national smallpox epidemic that spread out of effective control

This paper uses techniques of binary logistic regression to identify the spatial determinants of the last national epidemic of smallpox to spread in England and Wales, the variola minor epidemic of 1921–34. Adjusting for age and county-level variations in vaccination coverage in infancy, the analysis identifies a dose-response gradient with increasing odds of elevated smallpox rates in local government areas with (i) medium (odds ratio [OR] = 5.32, 95% Confidence Interval [95% CI] 1.96–14.41) and high (OR = 11.32, 95% CI 4.20–31.59) coal mining occupation rates and (ii) medium (OR = 16.74, 95% CI 2.24–125.21) and high (OR = 63.43, 95% CI 7.82–497.21) levels of residential density. The results imply that the spatial transmission of variola virus was facilitated by the close spatial packing of individuals, with a heightened transmission risk in coal mining areas of the country. A syndemic interaction between common respiratory conditions arising from exposure to coal dust and smallpox virus transmission is postulated to have contributed to the findings. We suggest that further studies of the geographical intersection of coal mining and acute infections that are transmitted via respiratory secretions are warranted

Chronicity and Mental Health Service Utilization for Anxiety, Mood, and Substance Use Disorders among Black Men in the United States; Ethnicity and Nativity Differences.

This study investigated ethnic and nativity differences in the chronicity and treatment of psychiatric disorders of African American and Caribbean Black men in the U.S. Data were analyzed from the National Survey of American Life, a population-based study which included 1859 self-identified Black men (1222 African American, 176 Caribbean Black men born within the U.S., and 461 Caribbean Black men born outside the U.S.). Lifetime and twelve-month prevalence of DSM-IV mood, anxiety, and substance use disorders (including Bipolar I and Dysthmia), disorder chronicity, and rate of mental health services use among those meeting criteria for a lifetime psychiatric disorder were examined. Logistic regression models were employed to determine ethnic differences in chronicity, and treatment utilization for disorders. While rates of DSM-IV disorders were generally low in this community sample of Black men, their disorders were chronic and remained untreated. Caribbean Black men born in the U.S. had higher prevalence of Post-Traumatic Stress Disorder, Major Depressive Disorder, and Alcohol Abuse Disorder compared with African American men. Foreign born Caribbean Black men experienced greater chronicity in Social Phobia and Generalized Anxiety Disorder compared to other Black Men. Utilization of mental health service was low for all groups of Black Men, but lowest for the foreign born Caribbean Black men. Results underscore the large unmet needs of both African American and Caribbean Black men in the United States. Results also highlight the role of ethnicity and nativity in mental disorder chronicity and mental health service utilization patterns of Black men

Calibration and characterisation with a new laser-based magnetostriction measurement system

A laser-based magnet measurement system has been developed to measure the magnetostrictive strain of large cylindrical samples. The measurement system incorporates a solenoid capable of generating a maximum magnetic field intensity of 3000 Oe and a laser displacement sensor. For calibration and evaluation purposes, the positive magnetostrictions of two different types of giant magnetostrictive Tb–Dy–Fe-based materials were accessed with this system. A magnetostrictive strain of 622 ppm was obtained at 3000 Oe for TbxDy1-xFe2-y, compared with 725 ppm for Tb0.27Dy0.73Fe2. A rod of sintered cobalt ferrite was also measured. This exhibited negative magnetostriction, with a maximum contraction of 260 ppm at 3000 Oe

Spatial Analysis of North Central Texas Traffic Fatalities 2001-2006

A traditional two dimensional (planar) statistical analysis was used to identify the clustering types of North Central Texas traffic fatalities occurring in 2001-2006. Over 3,700 crash locations clustered in ways that were unlike other researched regions. A two dimensional (x and y coordinates) space was manipulated to mimic a one dimensional network to identify the tightest clustering of fatalities in the nearly 400,000 crashes reported from state agencies from 2003-2006. The roadway design was found to significantly affect crash location. A one dimensional (linear) network analysis was then used to measure the statistically significant clustering of flow variables of after dark crashes and daylight crashes. Flow variables were determined to significantly affect crash location after dark. The linear and planar results were compared and the one dimensional, linear analysis was found to be more accurate because it did not over detect the clustering of events on a network

Mutants of phage bIL67 RuvC with enhanced Holliday junction binding selectivity and resolution symmetry

Viral and bacterial Holliday junction resolvases differ in specificity with the former typically being more promiscuous, acting on a variety of branched DNA substrates, while the latter exclusively targets Holliday junctions. We have determined the crystal structure of a RuvC resolvase from bacteriophage bIL67 to help identify features responsible for DNA branch discrimination. Comparisons between phage and bacterial RuvC structures revealed significant differences in the number and position of positively-charged residues in the outer sides of the junction binding cleft. Substitutions were generated in phage RuvC residues implicated in branch recognition and six were found to confer defects in Holliday junction and replication fork cleavage in vivo. Two mutants, R121A and R124A that flank the DNA binding site were purified and exhibited reduced in vitro binding to fork and linear duplex substrates relative to the wild-type, while retaining the ability to bind X junctions. Crucially, these two variants cleaved Holliday junctions with enhanced specificity and symmetry, a feature more akin to cellular RuvC resolvases. Thus, additional positive charges in the phage RuvC binding site apparently stabilize productive interactions with branched structures other than the canonical Holliday junction, a feature advantageous for viral DNA processing but deleterious for their cellular counterparts