How to protect estuaries in Durham, NH

Estuaries are some of the most diverse and fragile ecosystems on our planet. All over the nation, along the coastal states, half of the wetlands, about 55 million acres, have been destroyed (“Habitat Loss Nationwide,” n.d.). Most of these wetlands get Dutton 3 cleared and drained for development, agriculture, etc. In the estuaries located in the Gulf of Maine, development has doubled in the last forty years in the lower watershed (“Habitat Loss Nationwide,” n.d.). This has resulted in an increase in population and impervious surfaces, which correlates with the negative impacts to the watershed, such as runoff and sedimentation (National Research Council, 1987). Other factors have contributed to the degradation of the estuaries in the Piscataqua region such as sealevel rise and an increase in fertilizer use (citations). Some changes have been made to protect these estuaries, however, solving the cumulative impacts need to be included in the protection. Each individual activity is not independent of each other. Their activities work together to decrease the productivity and health of the estuaries. We have policies that have been created, and zoning that has been changed to improve estuaries, however, we need to take that next step forward to fill in the gaps. The goal of this paper is to analyze the current policies and programs, identify the gaps to improve and enhance the programs to be in line with the longstanding ideals of protection and conservation of Durham’s estuaries

Fear of the dark in children: is stationary night blindness the cause?

No abstract available

Extensive horizontal gene transfer in cheese-associated bacteria.

Acquisition of genes through horizontal gene transfer (HGT) allows microbes to rapidly gain new capabilities and adapt to new or changing environments. Identifying widespread HGT regions within multispecies microbiomes can pinpoint the molecular mechanisms that play key roles in microbiome assembly. We sought to identify horizontally transferred genes within a model microbiome, the cheese rind. Comparing 31 newly sequenced and 134 previously sequenced bacterial isolates from cheese rinds, we identified over 200 putative horizontally transferred genomic regions containing 4733 protein coding genes. The largest of these regions are enriched for genes involved in siderophore acquisition, and are widely distributed in cheese rinds in both Europe and the US. These results suggest that HGT is prevalent in cheese rind microbiomes, and that identification of genes that are frequently transferred in a particular environment may provide insight into the selective forces shaping microbial communities

Scanning laser source and scanning laser detection techniques for different surface crack geometries

Standard test samples typically contain simulated defects such as slots machined normal to the surface. However, real defects will not always propagate in this manner; for example, rolling contact fatigue on rails propagates at around 25º to the surface, and corrosion cracking can grow in a branched manner. Therefore, there is a need to understand how ultrasonic surface waves interact with different crack geometries. We present measurements of machined slots inclined at an angle to the surface normal, or with simple branched geometries, using laser ultrasound. Recently, Rayleigh wave enhancements observed when using the scanning laser source technique, where a generation laser is scanned along a sample, have been highlighted for their potential in detecting surface cracks. We show that the enhancement measured with laser detector scanning can give a more significant enhancement when different crack geometries are considered. We discuss the behaviour of an incident Rayleigh wave in the region of an angled defect, and consider mode-conversions which lead to a very large enhancement when the detector is close to the opening of a shallow defect. This process could be used in characterising defects, as well as being an excellent fingerprint of their presence

Non-contact ultrasonic detection of angled surface defects

Non-destructive testing is an important technique, and improvements are constantly needed. Surface defects in metals are not necessarily confined to orientations normal to the sample surface; however, much of the previous work investigating the interaction of ultrasonic surface waves with surface-breaking defects has assumed cracks inclined at 90° to the surface. This paper explores the interaction of Rayleigh waves with cracks which have a wide range of angles and depths relative to the surface, using a non-contact laser generation and detection system. Additional insight is acquired using a 3D model generated using finite element method software. A clear variation of the reflection and transmission coefficients with both crack angle and length is found, in both the out-of-plane and in-plane components. The 3D model is further used to understand the contributions of different wavemodes to B-Scans produced when scanning a sample, to enable understanding of the reflection and transmission behaviour, and help identify angled defects. Knowledge of these effects is essential to correctly gauge the severity of surface cracking

Travis Peak Formation, East Texas

Sandstone in the Travis Peak (Hosston) Formation has been extensively modified by burial diagenesis. Permeability in much of the formation has been reduced to less than 0.1 md as a result of compaction extensive precipitation of authigenic minerals, and minor pressure solution. Thin zones of higher porosity and permeability occur mainly near the top of the formation: porosity and permeability decrease with depth below the top. The Travis Peak Formation in East Texas is approximately 2,000 ft (600 m) thick; depth to the top of the formation ranges from 5,800 ft (1,770 m) to 9,400 ft (2,870 m). Travis Peak sandstone is fine- to very fine-grained quartzarenite and subarkose having an average composition of Q₉₅F₄R₁. Plagioclase feldspar is more abundant than orthoclase, and chert and low-rank metamorphic rock fragments are the most common lithic components. The first authigenic cement to precipitate was illite, which coated detrital grains with tangentially oriented crystals. Next, extensive quartz cement, averaging 17% of the rock volume in well-sorted sandstone, occluded much of the primary porosity. Quartz cement is most abundant in the lower Travis Peak, in well-connected sandstone beds that were deposited in braided streams. Oxygen-isotopic composition of quartz overgrowths indicates that they precipitated from meteoric fluids at temperatures of 130° to 165°F (55° to 75°C). These temperatures equate to depths of 3,000 to 5,000 ft (900 to 1,500 m). Dissolution of orthoclase and albitization of plagioclase followed quartz cementation and occurred prior to mid-Cretaceous movement of the Sabine Uplift. An abrupt loss of orthoclase occurs at 1,200 ft (365 m) below the top of the Travis Peak, and albitization is more extensive deeper in the formation. Illite (a second generation), chlorite, and ankerite precipitated after feldspar diagenesis; these late authigenic phases incorporate ferrous iron released by thermal reduction of iron compounds. Ankerite was derived primarily from early dolomite cement, but it incorporated some light carbon from maturation of organic matter and radiogenic strontium from feldspar dissolution. The oxygen-isotopic composition of pore fluids evolved during ankerite precipitation from -4 o/oo to +3 o/oo (SMOW); +3 o/oo is the present composition of Travis Peak water. Oil migrated into Travis Peak reservoirs about 65 mya from shale in the Bossier Formation. Later deasphalting of the oil filled much of the remaining porosity in some zones near the top of the formation with reservoir bitumen.Geological Science

A Genomic Point Mutation in the Extracellular Domain of the Thyrotropin Receptor in Patients with Graves’ Ophthalmopathy

Orbital and pretibial fibroblasts are targets of autoimmune attack in Graves' ophthalmopathy (GO) and pretibial dermopathy (PTD). The fibroblast autoantigen involved in these peripheral manifestations of Graves' disease and the reason for the association of GO and PTD with hyperthyroidism are unknown. RNA encoding the full-length extracellular domain of the TSH receptor has been demonstrated in orbital and dermal fibroblasts from patients with GO and normal subjects, suggesting a possible antigenic link between fibroblasts and thyrocytes. RNA was isolated from cultured orbital, pretibial, and abdominal fibroblasts obtained from patients with severe GO (n = 22) and normal subjects (n = 5). RNA was reverse transcribed, and the resulting cDNA was amplified by the polymerase chain reaction, using primers spanning overlapping regions of the entire extracellular domain of the TSH receptor. Nucleotide sequence analysis showed an A for C substitution in the first position of codon 52 in 2 of the patients, both of whom had GO, PTD, and acropachy. Genomic DNA isolated from the 2 affected patients, and not from an additional 12 normal subjects, revealed the codon 52 mutation by direct sequencing and AciI restriction enzyme digestions. In conclusion, we have demonstrated the presence of a genomic point mutation, leading to a threonine for proline amino acid shift in the predicted peptide, in the extracellular domain of the TSH receptor in two patients with severe GO, PTD, acropachy, and high thyroid-stimulating immunoglobulin levels. RNA encoding this mutant product was demonstrated in the fibroblasts of these patients. We suggest that the TSH receptor may be an important fibroblast autoantigen in GO and PTD, and that this mutant form of the receptor may have unique immunogenic properties