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The poem "Cover Us With Mountains" by V. C. McCabe is presented. First Line: Chemical Valley's cup runneth over; Last Line: for all that we have lost.

The article offers brief profiles of poets featured in the journal including Clint Carroll, Mark D. Hart and Pauletta Hansel.

Despite higher rates of tobacco use and smoking-related diseases among sexual minorities, tobacco cessation treatment-seeking behaviors (e.g., medication, nicotine replacement products) remain poorly understood across sexual orientation subgroups. This study examines tobacco cessation treatment-seeking behaviors associated with Diagnostic and Statistical Manual of Mental Disorders, 5th Edition tobacco use disorder (TUD) across the three major sexual orientation dimensions (identity, attraction, behavior) in U.S. adults. Prevalence estimates reflect data collected from a 2012-2013 national sample of adults 18 years and older. More than three-fourths of U.S. adults with TUD had never engaged in tobacco cessation treatment-seeking behaviors, regardless of sexual orientation. Despite having the highest rates of TUD, bisexual men and women had some of the lowest rates of tobacco cessation treatment-seeking. Men who identified as gay, reported same-sex attraction, or reported same-sex behaviors had the highest rates of tobacco cessation treatment-seeking. In contrast, women with same-sex attraction or same-sex behavior had higher rates of TUD but were less likely to engage in tobacco cessation treatment-seeking behaviors than women with only other-sex attraction or other-sex behavior, respectively. Heterosexual women were more likely to engage in tobacco cessation treatment-seeking than heterosexual men; this sex difference was not present for sexual minorities. Medications and nicotine replacement therapy products were the most prevalent forms of treatment-seeking. There were notable differences in tobacco cessation treatment-seeking behaviors based on sex and sexual orientation. Findings highlight the underutilization of tobacco cessation treatment-seeking among all U.S. adults and point to important factors to consider when working with sexual minorities who are trying to reduce or stop using tobacco.

Crossing the midline produces changes in axons such that they are no longer attracted to the midline. In Drosophila, Roundabout reaches high levels on axons once they have crossed the midline, and this prohibits recrossing. Roundabout protein levels are regulated by Commissureless. We show that Commissureless binds to and is regulated by the ubiquitin ligase DNedd4. We further show that the ability of Commissureless to regulate Roundabout protein levels requires an intact DNedd4 binding site and ubiquitin acceptor sites within the Commissureless protein. The ability of Commissureless to regulate Robo in the embryo also requires a Commissureless/DNedd4 interaction. Our results show that changes in axonal sensitivity to external cues during pathfinding across the midline makes use of ubiquitin-dependent mechanisms to regulate transmembrane protein levels.

The Xist gene is expressed exclusively from the inactive X chromosome and plays a central role in regulating X chromosome inactivation. Here we describe experiments aimed at defining the extent of the active chromatin domain of the expressed Xist allele. By using an allele-specific general DNaseI sensitivity assay we show that there is preferential digestion of the expressed allele at sites within the transcribed locus but not in flanking sites located up to 70 kb 5'. A putative proximal boundary for the Xist domain is located within 10 kb upstream of promoter P1. Chromatin in the expressed domain was found to be acetylated at H4 in XX somatic cells but also in XY cells, where Xist is never expressed. A single clear exception to this was the Xist promoter, which is acetylated only in XX cells. These observations concur with the view that H4 acetylation may not be a general marker of active chromatin domains and further support data implicating local promoter acetylation as being of primary functional significance in vivo.

We have investigated the role of histone acetylation in X chromosome inactivation, focusing on its possible involvement in the regulation of Xist, an essential gene expressed only from the inactive X (Xi). We have identified a region of H4 hyperacetylation extending up to 120 kb upstream from the Xist somatic promoter P1. This domain includes the promoter P0, which gives rise to the unstable Xist transcript in undifferentiated cells. The hyperacetylated domain was not seen in male cells or in female XT67E1 cells, a mutant cell line heterozygous for a partially deleted Xist allele and in which an increased number of cells fail to undergo X inactivation. The hyperacetylation upstream of Xist was lost by day 7 of differentiation, when X inactivation was essentially complete. Wild-type cells differentiated in the presence of the histone deacetylase inhibitor Trichostatin A were prevented from forming a normally inactivated X, as judged by the frequency of underacetylated X chromosomes detected by immunofluorescence microscopy. Mutant XT67E1 cells, lacking hyperacetylation upstream of Xist, were less affected. We propose that (i) hyperacetylation of chromatin upstream of Xist facilitates the promoter switch that leads to stabilization of the Xist transcript and (ii) that the subsequent deacetylation of this region is essential for the further progression of X inactivation.

A physical map encompassing approximately 2.0 megabases (Mb) in the region of the mouse X-inactivation center has been constructed. The map extends from the Gjb-1 locus to the Xist locus and demonstrates the order of probes inseparable by genetic analysis. The deduced locus order is as follows: Gjb-1, Ccg-1, DXCrc171, Rps4, Phka, DXCrc177, DXCrc318, Xist. Detailed physical mapping in the region between the Phka and Xist loci indicates the position of CpG-rich islands associated with the 5' end of genes. The DXCrc177 and DXCrc318 loci, both defined by probes derived from linking clones, are associated with CpG-rich islands. The map provides a framework for the isolation of underlying sequences in the mouse X-inactivation center region.

The Xist gene maps to the X inactivation center region in both mouse and human, and previous analysis of the 3' end of the gene has demonstrated inactive X-specific expression, suggesting a possible role in X inactivation. We have now analyzed the entire mouse Xist gene. The mature inactive X-specific transcript is 15 kb in length and contains no conserved ORF. The Xist sequence contains a number of regions comprised of tandem repeats. Comparison with the human XIST gene demonstrates significant conservation of sequence and gene structure. Xist RNA is not associated with the translational machinery of the cell and is located almost exclusively in the nucleus. Together with conservation of inactive X-specific expression, these findings support a role for Xist in X inactivation, possibly as a functional RNA or as a chromatin organizer region.

X-chromosome inactivation in mammals is a regulatory phenomenon whereby one of the two X chromosomes in female cells is genetically inactivated, resulting in dosage compensation for X-linked genes between males and females. In both man and mouse, X-chromosome inactivation is thought to proceed from a single cis-acting switch region or inactivation centre (XIC/Xic). In the human, XIC has been mapped to band Xq13 (ref. 6) and in the mouse to band XD (ref. 7), and comparative mapping has shown that the XIC regions in the two species are syntenic. The recently described human XIST gene maps to the XIC region and seems to be expressed only from the inactive X chromosome. We report here that the mouse Xist gene maps to the Xic region of the mouse X chromosome and, using an interspecific Mus spretus/Mus musculus domesticus F1 hybrid mouse carrying the T(X;16)16H translocation, show that Xist is exclusively expressed from the inactive X chromosome. Conservation between man and mouse of chromosomal position and unique expression exclusively from the inactive X chromosome lends support to the hypothesis that XIST and its mouse homologue are involved in X-chromosome inactivation.

2 independent and geographically disparate samples show that physically abused 3-6-year-old children have cranial/facial proportions that are atypically older than their nonabused age-mates. 2 independent photographic samples corroborated this finding, 1 investigating 2-7-year-olds and 1 investigating 12-15-year olds. All 4 samples were blind rated by researchers who were unaware of the hypothesis. Comparisons are made with other physical variables associated with age level such as height. It is suggested that cranial/facial proportion is a particularly salient abstract specification for age level and may be used without awareness in caregiving decisions. This may lead to caregivers' unrealistic expectations of youngsters who appear atypically older than their chronological age. If these children do not meet these expectations, either as to how they should typically appear or typically behave, they may be more vulnerable to abuse. This possibility lends some support to Lorenz's idea that "infant-schema" properties such as physical proportions may be implicated in caregiving. However, it is asserted that cranial/facial information is simply a specification for age level, not a cause of abusive behavior.

The attenuation of a light beam by a suspension of platelets in plasma was examined theoretically and experiments were performed to confirm this analysis. Interfering and modifying inputs were identified and their effects quantified. Recommendations for instrument design are made which minimise the effects of spurious inputs and enable platelet concentration in plasma to be estimated by simple optical methods. The most important recommendations are: (i) the use of light in the range 850--1000 nm so that water may be used instead of isologous platelet-free plasma as a blank and (ii) the emphasis on the need for the calibration of the system and the necessity for re-calibration if the optical system is disturbed or adjusted.