Maternal smoking during pregnancy and birthweight - A propensity score matching approach

There is accumulated evidence of the existence of a deleterious effect of smoking on birth outcomes. Understanding the effect of smoking on pregnancy is a critical issue because of the public policy implications for dissuading maternal smoking. We explore this issue by using the propensity score method and compare that with parametric estimators. First we estimate the treatment effect of smoking during pregnancy on different birth outcomes. Then, we extend the method to the case of the multi-treatment "intensity of smoking". The deleterious effect of smoking is found robust to the different estimation methods used.Smoking, birth outcomes, causal effects, propensity score and matching

Monoreactive high affinity and polyreactive low affinity rheumatoid factors are produced by CD5+ B cells from patients with rheumatoid arthritis.

In patients with rheumatoid arthritis (RA), circulating CD5+ B lymphocytes, but not CD5- B lymphocytes, are increased in number and size, exist in an activated state, spontaneously proliferate, and secrete Ig that binds to the Fc fragment of IgG. By constructing continuous mAb-secreting cell lines from CD5+ B lymphocytes, the properties and dissociation constants (Kd) of these antibodies were determined. Two types of rheumatoid factors (RFs) with discrete reactivities were produced. The first type is polyreactive and binds with relatively low affinity (Kd, 10(-5) mol/liter) to the Fc fragment of IgG. These antibodies are similar to those produced by CD5+ B cells from healthy subjects. The second type of RF is monoreactive and binds with higher affinity (Kd, 10(-7) mol/liter) to the Fc fragment of IgG. These latter autoantibodies are produced by CD5+ B cells of RA patients, but not healthy subjects. Long-term longitudinal studies are needed to determine the role of these two types of RFs in the pathogenesis of RA

Effects of a Novel Dental Gel on Plaque and Gingivitis: A Comparative Study.

ObjectivesThe goal of this prospective, randomized, controlled, double-blinded study was to evaluate the effects of a novel dental gel on plaque and gingival health. The dental gel was designed to (1) break up and prevent re-accumulation of microbial biofilm, and (2) inhibit metal mediated inflammation.Materials and methodsTwenty-five subjects with moderate gingival inflammation (Löe and Silness Gingival Index ≥2) and pocket depths <4 were randomly assigned to brush twice daily for 21 days with the test or the control dental gel. On Days 0, 7, 14 and 21, plaque levels (Quigley-Hein, Turesky Modification Plaque Index), gingival inflammation (Löe and Silness Gingival Index) and gingival bleeding (modified Sulcus Bleeding Index) were determined by one blinded, investigator using a pressure sensitive probe.ResultsAfter 3 weeks, all 3 clinical indices were significantly improved in both groups (P<0.05) and significantly lower in the test group (P<0.05).ConclusionThe novel dental gel formulation was provided effective plaque control and reduced gingival inflammation.Clinical relevanceA novel dentifrice formulation may be an effective tool for plaque removal and maintaining gingival health

Discharge In the Law of Arbitration

The vast majority of arbitrators will refuse to find just cause unless the discharge penalty bears some reasonable relation to the seriousness of the grievant\u27s offense. They believe it to be their responsibility to determine whether the punishment fits the crime by realistically appraising the wrongful act\u27s deleterious effects on the industrial community. If the grievant\u27s proven offense appears to merit discipline short of discharge, the arbitrator usually will feel compelled to modify the discharge penalty in favor of some lesser degree of discipline. Since this amounts to a review of the penalty imposed by management, there is a substantial question as to whether the arbitrator has this authority. Generally, arbitrators have not been too concerned with this problem, and they consistently assert jurisdiction to reduce the discharge penalty on the ground that the power is implied in their authority to decide and adjust the dispute submitted by the parties.The courts, in actions to vacate or enforce awards, have shown a general tendency to favor the arbitrator\u27s assertion of power to modify the penalty imposed unless this power is clearly denied him by the collective agreement or submission. This tendency indicates that arbitrators will be given some leeway in formulating adequate remedies for the breach of collective bargaining agreements. Looking to the future, one wonders whether arbitrators will be allowed to formulate additional and more controversial remedies under the implied authority rationale. It is reasonable to assume, however, that there will be a corresponding development in the arbitral remedy power as the arbitration process increasingly becomes the principal means for resolving labor disputes

Heat-transfer distributions on biconics at incidence in hypersonic-hypervelocity He, N2, air, and CO2 flows

Laminar heat transfer rates were measured on spherically blunted, 13 deg/7 deg on axis and bent biconics (fore cone bent 7 deg upward relative to aft cone) at hypersonic hypervelocity flow conditions in the Langley Expansion Tube. Freestream velocities from 4.5 to 6.9 km/sec and Mach numbers from 6 to 9 were generated using helium, nitrogen, air, and carbon dioxide test gases, resulting in normal shock density ratios from 4 to 19. Angle of attack, referenced to the axis of the aft cone, was varied from 0 to 20 deg in 4 deg increments. The effect of nose bend, angle of attack, and real gas phenomena on heating distributions are presented along with comparisons of measurement to prediction from a code which solves the three dimensional parabolized Navier-Stokes equations

Maternal smoking during pregnancy and birthweight : a propensity score matching approach

There is accumulated evidence of the existence of a deleterious effect of smoking on birth outcomes. Whether there is a causal link or a mere statistical association is not clear. Understanding the effect of smoking on pregnancy is a critical issue because of the public policy implications for dissuading maternal smoking. This study was designed to distinguish causal links from statistical association in the relationship between fetal exposure to maternal smoking and birth outcomes. Although the task involves several aspects of estimation we restrict our focus to the issue of self-selection. We explore this issue by using the propensity score method and compare that with parametric estimators. First we estimate the treatment effect of smoking during pregnancy on different birth outcomes. Then, we extend the method to the case of the multi-treatment “intensity of smoking”. The deleterious effect of smoking is found robust to the different estimation methods used.Fundação para a Ciência e a Tecnologia (FCT

Over-wintering Characteristics of West-Central Wisconsin Blanding's Turtles, Emydoidea blandingii

Hibernation of adult-sized Blanding's Turtles was studied at two west-central Wisconsin sites between 1991 and 2008. Turtles arrived at hibernacula from mid September to early October, spending 126 to 216 days at these sites, and generally emerged in early April yearly. Sixty percent of females and 30 percent of males hibernated in natural over man-made structures as hibernation sites. Anoxic conditions near five hibernation sites ranged from 78 to 100 days. Shell temperatures of three turtles monitored over five winters remained at <1°C a mean of 2,274 hours each winter. Over the same period, four turtles' temperatures were between 0° and -1°C a mean of 302 hours. During the course of our study, hibernating west-central Wisconsin Blanding's Turtles demonstrated a remarkable degree of both cold and anoxia-tolerance similar to that observed among Painted Turtles (Chrysemys picta) and Snapping Turtles (Chelydra serpentina)

Asymmetric magnetic reconnection with a flow shear and applications to the magnetopause

We perform a theoretical and numerical study of anti-parallel 2D magnetic reconnection with asymmetries in the density and reconnecting magnetic field strength in addition to a bulk flow shear across the reconnection site in the plane of the reconnecting fields, which commonly occurs at planetary magnetospheres. We predict the speed at which an isolated X-line is convected by the flow, the reconnection rate, and the critical flow speed at which reconnection no longer takes place for arbitrary reconnecting magnetic field strengths, densities, and upstream flow speeds, and confirm the results with two-fluid numerical simulations. The predictions and simulation results counter the prevailing model of reconnection at Earth's dayside magnetopause which says reconnection occurs with a stationary X-line for sub-Alfvenic magnetosheath flow, reconnection occurs but the X-line convects for magnetosheath flows between the Alfven speed and double the Alfven speed, and reconnection does not occur for magnetosheath flows greater than double the Alfven speed. We find that X-line motion is governed by momentum conservation from the upstream flows, which are weighted differently in asymmetric systems, so the X-line convects for generic conditions including sub-Alfvenic upstream speeds. For the reconnection rate, while the cutoff condition for symmetric reconnection is that the difference in flows on the two sides of the reconnection site is twice the Alfven speed, we find asymmetries cause the cutoff speed for asymmetric reconnection to be higher than twice the asymmetric form of the Alfven speed. The results compare favorably with an observation of reconnection at Earth's polar cusps during a period of northward interplanetary magnetic field, where reconnection occurs despite the magnetosheath flow speed being more than twice the magnetosheath Alfven speed, the previously proposed suppression condition.Comment: 46 pages, 7 figures, abstract abridged here, accepted to Journal of Geophysical Research - Space Physic