Sequencing seismograms: A panoptic view of scattering in the core-mantle boundary region.

Scattering of seismic waves can reveal subsurface structures but usually in a piecemeal way focused on specific target areas. We used a manifold learning algorithm called "the Sequencer" to simultaneously analyze thousands of seismograms of waves diffracting along the core-mantle boundary and obtain a panoptic view of scattering across the Pacific region. In nearly half of the diffracting waveforms, we detected seismic waves scattered by three-dimensional structures near the core-mantle boundary. The prevalence of these scattered arrivals shows that the region hosts pervasive lateral heterogeneity. Our analysis revealed loud signals due to a plume root beneath Hawaii and a previously unrecognized ultralow-velocity zone beneath the Marquesas Islands. These observations illustrate how approaches flexible enough to detect robust patterns with little to no user supervision can reveal distinctive insights into the deep Earth.

Alteration of the endocannabinoid system in mouse brain during prion disease.

Prion diseases are neurodegenerative disorders characterized by deposition of the pathological prion protein (PrPsc) within the brain of affected humans and animals. Microglial cell activation is a common feature of prion diseases; alterations of various neurotransmitter systems and neurotransmission have been also reported. Owing to its ability to modulate both neuroimmune responses and neurotransmission, it was of interest to study the brain endocannabinoid system in a prion-infected mouse model. The production of the endocannabinoid, 2-arachidonoyglycerol (2-AG), was enhanced 10 weeks post-infection, without alteration of the other endocannabinoid, anandamide. The CB2 receptor expression was up-regulated in brains of prion-infected mice as early as 10 weeks and up to 32 weeks post-infection whereas the mRNAs of other cannabinoid receptors (CBRs) remain unchanged. The observed alterations of the endocannabinoid system were specific for prion infection since no significant changes were observed in the brain of prion-resistant mice, that is, mice devoid of the Prnp gene. Our study highlights important alterations of the endocannabinoid system during early stages of the disease long before the clinical signs of the disease.

[Thailand: resurgence of infectious diseases and epidemiologic transition]. / Thaïlande: résurgences infectieuses et transition epidémiologique.

Despite progress in various facts (sanitation, education, access to health care...) that allowed a significant reduction in infectious and parasitic diseases, they persist in some poor geographical areas and populations most in need, especially in young children. An epidemiological transition (increased incidence of cancers, cardiovascular attacks...) clearly tends to replace the old public health problems, rather in urban areas and among the most advantaged social classes. Diseases (re)emerging are also serious concerns for the future: return of resistant malaria, outbreaks of severe clinic forms of dengue, explosion of VHI/TB resistant....

Increased eNO and pulmonary iNOS expression in eNOS null mice.

Nitric oxide (NO) is a major regulatory molecule of the cardiovascular system; however, measurement of vascular NO synthesis in vivo represents a major challenge. NO stemming from the lower respiratory tract has been used as a marker of vascular endothelial function. Experimental evidence for this concept is lacking. Therefore, the aim of the present study was to investigate this relationship. Lower respiratory tract exhaled NO concentration, together with systemic and pulmonary artery pressure, was measured in endothelial nitric oxide synthase (NOS) (eNOS) null mice (eNOS-/-). Similar studies were performed in inducible NOS (iNOS) null mice (iNOS-/-). Defective endothelial NO synthesis in eNOS-/- mice (evidenced by systemic and pulmonary hypertension) was associated with augmented exhaled NO levels (12.5 +/- 1.9 versus 9.8 +/- 1.2 parts per billion (ppb), eNOS-/- versus wild type), whereas normal endothelial NO synthesis in iNOS-/- mice was associated with decreased exhaled NO levels (4.3 +/- 1.5 ppb). Augmented exhaled NO levels in eNOS-/- mice were associated with upregulation of iNOS expression in the lung. These results indicate that inducible nitric oxide synthase is a major determinant of gaseous nitric oxide production in the lung, and lower respiratory tract exhaled nitric oxide does not always represent a marker of vascular endothelial nitric oxide synthesis.

MCPA permeation through protective gloves.

Permeation of 4-chloro-2-methylphenoxyacetic acid (MCPA) in commercial herbicide formulations through common protective glove types was evaluated to aid in the selection of appropriate skin protection. The ASTM test method F739-91 was used to measure the permeation of two undiluted formulations, one containing a salt, and the other an ester form of MCPA. The four glove types tested were natural rubber, neoprene 73, nitrile 37-145, and Viton-coated chloroprene. Triplicate tests of each combination of formulation and glove material were conducted. Permeation cells with a 0.01 M sodium hydroxide collection medium were used for the experiments. Aliquots of the collection medium were withdrawn at regular intervals and acidified, and quantification of the free acid was achieved using HPLC-UV (230 nm). There was no appreciable permeation of the salt formulation over a 24-hour test period. For the ester formulation, the following mean steady-state permeation rate (microg x cm(-2) min(-1)) and mean lag time (hours), respectively, were measured: Viton (0.06, 17.8), natural rubber (0.08, 15.4), neoprene 73 (0.21, 15.1), and nitrile (0.04, 24.2). Permeation was associated with significant swelling, averaging a nearly 30 percent increase from the pre-immersion thickness. All four glove types provide adequate protection against permeation by the salt formulation and at least eight-hour protection against the ester formulation. Given the greater permeation of the ester formulation, the salt formulation of MCPA herbicide should be used whenever possible.

Occurrence of pathogenic microorganisms in the Saint Lawrence River (Canada) and comparison of health risks for populations using it as their source of drinking water.

A 300-km portion of the Saint Lawrence hydrological basin in the province of Québec (Canada) and 45 water treatment plants were studied. River water used by drinking water treatment plants was analyzed (6-L sample volumes) to determine the level of occurrence of bacterial indicators (total coliforms, fecal coliforms, and Clostridium perfringens) and pathogens (Giardia lamblia, Cryptosporidium, human enteric viruses). Pathogens and bacterial indicators were found at all sites at a wide range of values. Logistic regression analysis revealed significant correlations between the bacterial indicators and the pathogens. Physicochemical and treatment practices data were collected from most water treatment plants and used to estimate the level of removal of pathogens achieved under cold (0 degree C-4 degrees C) and warm (20 degrees C-25 degrees C) water temperature conditions. The calculated removal values were then used to estimate the annual risk of Giardia infection using mathematical models and to compare the sites. The estimated range of probability of infection ranged from 0.75 to less than 0.0001 for the populations exposed. Given the numerous assumptions made, the model probably overestimated the annual risk, but it provided comparative data of the efficacy of the water treatment plants and thereby contributes to the protection of public health.

A birth father and adoption in the perinatal setting.

The role of the birth father in adoption is debated by lawyers, adoption professionals, and members of the adoption triad. At issue is how best to involve the birth father in the adoption plan while respecting the feelings of the birth mother, prospective adoptive couple, and rights of the child. This article examines emotional, legal and practice issues related to a birth father in adoption and implications for the perinatal social worker.

A psychiatric home care program: a report based on three years' experience (1962-1964).

The activities covering a three-year period of a psychiatric home care treatment program attached to a psychiatric unit of a general hospital are described. A detailed account of its operation and the roles played by each member of the team is given. This service frequently provides a substitute for hospitalization in the management of both acute and chronic psychiatric states and thereby constitutes an important preventive measure in the field of public health. Even if the initial attitude of the patient is negative it is possible to gain the co-operation of the family who become a useful ally in the treatment. The co-operation of the patient is not as essential as has been thought. The traditional role of the psychiatrist is reversed by virtue of his attending the patient at home. The active participation of social agencies is an integral part of the treatment.