Shock compression of feldspars

Hugoniot data for oligoclase and microcline to 670 and 580 kb and release adiabat data for oligoclase were obtained by means of the inclined mirror and immersed-foil-reflected-light techniques, respectively. Oligoclase and microcline have Hugoniot elastic limits in the range of 40–55 and 80–85 kb. These limits increase slightly with increasing driving shock pressure. Above the elastic limit, extending to ∼300 and ∼400 kb, transition regions of anomalously high compression are observed for microcline and oligoclase. These data and the data of McQueen, Marsh, and Fritz for albitite and anorthosite indicate that at successively higher shock pressures within this region, the feldspars gradually transform to a high-pressure, high-density polymorph. This polymorph probably corresponds to the rutile-like hollandite structure obtained in high-pressure quenching experiments by Kume, Matsumoto, and Koizumi (in KAlGe_3O_8) and by Ringwood, Reid, and Wadsley (in KAlSo_3O_8, microcline). In the hollandite structure germanium or silicon is in octahedral coordination with oxygen. The zero-pressure density and the Birch-Murnaghan equation of state parameters for the adiabat and isotherm are calculated for the high-pressure polymorphs of oligoclase, microcline, anorthosite, and albitite. The release adiabat centered at 180 kb indicates that at this shock pressure some (∼15%) of the hollandite phase forms but apparently reverts to a lower-density phase on pressure release. Release adiabat curves centered at 272 and 417 kb and calculated postshock temperatures indicate that material of feldspar composition recovered from meteorite and laboratory impacts is converted to the hollandite structure upon shock compression; upon pressure release this material probably reverts to the low-density maskelynite form

The prevalence of polycystic ovary syndrome in reproductive-aged women of different ethnicity: a systematic review and meta-analysis

The prevalence of PCOS was investigated in many studies in different continents. However, there is no established prevalence of PCOS for distinct ethnic groups. In the current analysis, we conducted searches in PubMed, The Cochrane Library, EMBASE, CINAHL up to Jan. 2017 to identify studies reporting prevalence of PCOS in the general female population. Forty-two studies were identified, with 13 eligible for evidence synthesis. The prevalence among different ethnicity was estimated using random effect modelling. Our results suggested the lowest prevalence in Chinese women(2003 Rotterdam criterion: 5.6% 95% interval: 4.4–7.3%), and then in an ascending order for Caucasians (1990 NIH criterion: 5.5% 95% interval: 4.8–6.3%), Middle Eastern (1990 NIH 6.1% 95% interval: 5.3–7.1%; 2003 Rotterdam 16.0% 95% interval: 13.8–18.6%; 2006 AES 12.6% 95% interval: 11.3–14.2%), and Black women (1990 NIH: 6.1% 95% interval: 5.3–7.1%).There is variation in prevalence of PCOS under different diagnostic criteria and across ethnic groups. This emphasises the need for ethnicity-specific guidelines for PCOS to prevent under- or over-diagnosis of the condition given that under-diagnosis may lead to rapid conversion of metabolic disorders for patients whereas over-diagnosis may exert negative psychological effects on patients which worsens the major symptoms of PCOS

Ecological comparison of the risks of mother-to-child transmission and clinical manifestations of congenital toxoplasmosis according to prenatal treatment protocol

We compared the relative risks of mother-to-child transmission of Toxoplasma gondii and clinical manifestations due to congenital toxoplasmosis associated with intensive prenatal treatment in Lyon and Austria, short term treatment in 51% of Dutch women, and no treatment in Danish women. For each cohort, relative risks were standardized for gestation at seroconversion. In total, 856 mother–child pairs were studied: 549 in Lyon, 133 in Austria, 123 in Denmark and 51 in The Netherlands. The relative risk for mother-to-child transmission compared to Lyon was 1·24 (95% CI: 0·88, 1·59) in Austria; 0·59 (0·41, 0·81) in Denmark; and 0·65 (0·37, 1·01) in The Netherlands. Relative risks for clinical manifestations compared with Lyon (adjusted for follow-up to age 3 years) were: Austria 0·19 (0·04, 0·51); Denmark 0·60 (0·13, 1·08); and The Netherlands 1·46 (0·51, 2·72). There was no clear evidence that the risk of transmission or of clinical manifestations was lowest in centres with the most intensive prenatal treatment

Habitat Management for Northern Bobwhites in Wisconsin: A Long-Term Assessment

An experimental habitat management program was initiated to improve the carrying capacity for northern bobwhites ( Colinus virginianus) on private lands by the Wisconsin Department of Natural Resources (WDNR) in 1974. During 1975-80, extensive habitat restoration was undertaken on a 60-mi2 (l55-km 2) study area in Richland County to restore hedge row cover, improve riparian corridors and woodlot edges, and construct plots of food and shelter to function as wintering sites for bobwhites. Previous investigations in Wisconsin have documented that the long-term decline of bobwhites was the result of habitat deterioration, principally hedgerow cover. Elsewhere, continuous declines in bobwhite abundance suggest a re-evaluation of the validity of time-honored habitat management practices is in order. Therefore, it seemed appropriate to test the impact of extensive attempts at habitat restoration, especially the development of hedgerows, on one small treatment area in the northern fringe of the geographic range of the northern bobwhite. After 10-15 years of growth, only 25% of the planted hedges were found to be effective for wintering bobwhites (i.e., closed canopies and producing fruits). Planted hedgerow cover suffered from poor survival due to deer browsing, competition from other surrounding vegetation, and changes in property owners and attitudes as farms were sold. Linear brushy cover was measured in 1990 and compared to similar estimates from 1978. During the 12-year span, brushy linear cover, including project hedges, decreased by 41% (5,995 to 3,545 yards/square mile; 2,531 to 1,497 meters/square kilometer). In addition, managed winter food resources after 1980 were reduced by half compared to earlier efforts. Through 1991, bobwhite population trends on the treatment area did not differ from statewide trends, indicating that extensive habitat restoration work had no discernible impact with respect to reversing population declines. Over 60% of the annual variability in bobwhite abundance in Richland County is related to the severity of winters. Despite these results, we still cannot discount the value of managing for hedgerows in Wisconsin. Achievements of this project include: (I) developing a bobwhite management strategy on a landscape scale, (2) gaining a high level of landowner cooperation, and (3) implementing an extensive amount of habitat restoration on private agricultural lands at minimal costs. The major problem with our overall approach is that such habitat restoration work requires continuous attention and maintenance over time to maintain effectiveness. Landowners, while highly cooperative, are not interested in protecting or maintaining habitat improvements for wildlife unless they have a vested stake in the project (i.e., a sense of ownership ). Habitat restoration on private agricultural lands necessitates first working to change landowner attitudes towards wildlife, with the development of private lands habitat programs as a secondary concern. The outlook for northern bobwhites in the northern fringe of their range is not bright. Northern bobwhite populations will not recover unless they become a by-product of the contemporary agricultural landscape. Unfortunately, this is not the case in Wisconsin and it is unlikely to change in the foreseeable future

On the Bartnik extension problem for the static vacuum Einstein equations

We develop a framework for understanding the existence of asymptotically flat solutions to the static vacuum Einstein equations with prescribed boundary data consisting of the induced metric and mean curvature on a 2-sphere. A partial existence result is obtained, giving a partial resolution of a conjecture of Bartnik on such static vacuum extensions. The existence and uniqueness of such extensions is closely related to Bartnik's definition of quasi-local mass.Comment: 33 pages, 1 figure. Minor revision of v2. Final version, to appear in Class. Quantum Gravit

Innovative marketing. The concept and function

This article is theoretical in nature. Any development of innovation begins with the development of creative ideas that will is the starting point for innovation Innovative marketing is aimed at the efficient introduction of these new ideas