Landscape Drivers of Dynamic Change in Water Quality of U.S. Rivers.

Water security is a top concern for social well-being, and dramatic changes in the availability of freshwater have occurred as a result of human uses and landscape management. Elevated nutrient loading and perturbations to major ion composition have resulted from human activities and have degraded freshwater resources. This study addresses the emerging nature of streamwater quality in the 21st century through analysis of concentrations and trends in a wide variety of constituents in streams and rivers of the U.S. Concentrations of 15 water quality constituents including nutrients, major ions, sediment, and specific conductance were analyzed over the period 1982-2012 and a targeted trend analysis was performed from 1992 to 2012. Although environmental policy is geared toward addressing the long-standing problem of nutrient overenrichment, these efforts have had uneven success, with decreasing nutrient concentrations at urbanized sites and little to no change at agricultural sites. Additionally, freshwaters are being salinized rapidly in all human-dominated land use types. While efforts to control nutrients are ongoing, rapid salinity increases are ushering in a new set of poorly defined issues. Increasing salinity negatively affects biodiversity, mobilizes sediment-bound contaminants, and increases lead contamination of drinking water, but its effects are not well integrated into current paradigms of water management.

Emergency joint aspiration: a guide for radiologists on call.

Septic arthritis is a disabling and possibly life-threatening disease that requires early diagnosis for optimal management. It is important that clinical and imaging features of septic arthritis be promptly identified. In addition, because other disease entities may have characteristics similar to those of septic arthritis, analysis of a needle biopsy specimen may be necessary for differential diagnosis. Radiologists may be asked to perform emergent aspiration of a possibly infected joint. It is important that those who perform aspiration procedures be familiar with a safe and effective imaging-guided arthrocentesis technique that is tailored to the individual patient and the specific joint affected.

The anatomy of a wrinkle ridge revealed in the wall of Melas Chasma, Mars.

Wrinkle ridges are among the most common tectonic structures on the terrestrial planets, and provide important records of the history of planetary strain and geodynamics. The observed broad arches and superposed narrow wrinkles are thought to be the surface manifestation of blind thrust faults, which terminate in near-surface volcanic sequences and cause folding and layer-parallel shear. However, the subsurface tectonic architecture associated with the ridges remains a matter of debate. Here we present direct observations of a wrinkle ridge thrust fault where it has been exposed by erosion in the southern wall of Melas Chasma on Mars. The thrust fault has been made resistant to erosion, likely due to volcanic intrusion, such that later erosional widening of the trough exposed the fault plane as a 70 km-long ridge extending into the chasma. A plane fit to this ridge crest reveals a thrust fault with a dip of 13° (+8°, -7°) between 1 and 3.5 km depth below the plateau surface, with no evidence for listric character in this depth range. This dip is significantly lower than the commonly assumed value of 30°, which, if representative of other wrinkle ridges, indicates that global contraction on Mars may have been previously underestimated.

Neoprene splinting: dermatological issues.

Occupational therapists are expanding their use of custom and commercial soft splints fabricated from neoprene (polychloroprene), but little has been written regarding dermatological issues associated with this material. Skin contact with neoprene poses two dermatological risks: allergic contact dermatitis (ACD) and miliaria rubra (i.e., prickly heat). Allergic reaction to neoprene is generally ascribed to the accelerants used to manufacture the man-made rubber, specifically thiourea compounds and mercaptobenzothiazole (MBT). Symptoms of neoprene-related ACD include itching, skin eruptions, swelling, and hemorrhages into the skin. Miliaria rubra creates small, red, elevated, inflammatory papules and a tingling, burning sensation. Although neoprene hypersensitivity is rare, its incidence may grow as neoprene becomes a more commonly used material. It is recommended that therapists screen patients for a history of dermatological reactions to neoprene or other materials containing thiourea compounds or MBT and educate patients to discontinue splint use if dermatological symptoms develop. Therapists are also encouraged to notify splint manufacturers regarding all ACD reactions.

Principles for the use of mechanical restraints in a medical facility by staff and security officers.

The author discusses the use of restraints by a healthcare security force. Before restraints are used, have clear and documented policies and procedures on the proper application, he advises. When used properly, they help provide a safe and secure environment for staff, patients, and visitors.

High-contrast solid-state electrochromic devices of viologen-bridged polysilsesquioxane nanoparticles fabricated by layer-by-layer assembly.

Water-soluble silsesquioxane nanoparticles (NPs) incorporating viologen groups (PXV; 1,1'-bis[3-(trimethoxysilyl)propyl]-4,4'-bipyridinium iodide) have been synthesized by sol-gel polymerization. The electrochromic properties of the bulk film fabricated by layer-by-layer (LbL) assembly have been examined, along with their incorporation into solid-state devices. The orange LbL films show high thermal stability and exhibit a maximum UV-vis absorption at 550 nm. Electrochromic switching of the NPs in liquid electrolyte as well as in the solid state was evaluated by a kinetic study via measurement of the change in transmission (% T) at the maximum contrast. Cyclic voltammograms of the PXV NP LbL films exhibit a reversible reduction at -0.6 V vs Ag/AgCl in a 0.1 M NaClO4(aq) solution, revealing good electrochromic stability, with a color change from orange to dark purple-blue at applied potentials ranging from -0.7 to -1.3 V. Cathodically coloring PXV NP solid-state devices exhibit a switching time of a few seconds between the purple-blue reduced state and the orange oxidized state, showing a contrast of 50% at 550 nm and a coloration efficiency of 205 cm2/C. Their solubility and fairly fast electrochromic switching ( approximately 3 s) at low switching voltages (between 0 and 3.0 V), along with their stability under atmospheric conditions, make PXV NPs good candidates for electrochromic displays.

High contrast solid state electrochromic devices based on Ruthenium Purple nanocomposites fabricated by layer-by-layer assembly.

Electrochromic Ruthenium Purple-polymer nanocomposite films, fabricated by multilayer assembly, were found to exhibit sub-second switching speed and the highest electrochromic contrast reported to date for any inorganic material.

Lateral meniscus root tear and meniscus extrusion with anterior cruciate ligament tear.

PURPOSE: To retrospectively determine the prevalence of posterior lateral meniscus root tears (LMRTs), as depicted on magnetic resonance (MR) images, in patients with an anterior cruciate ligament (ACL) tear and to investigate the association of LMRTs with lateral meniscus extrusion and other ligament injuries. MATERIALS AND METHODS: Institutional review board approval was obtained; informed consent was not required. This study was HIPAA compliant. MR images were obtained in 174 male and 119 female patients (mean age, 37 years; age range, 16-87 years) and retrospectively reviewed for LMRT, medial meniscus root tear (MMRT), nonroot meniscus tear, meniscus extrusion, and presence of meniscofemoral ligaments (MFLs). The chi2 and unpaired Student t tests were performed. RESULTS: In 33 patients, 34 meniscus root tears were identified. An LMRT was present in 26 (9.8%) of 264 patients, and an MMRT was present in eight (3.0%) (P=.008). Lateral meniscus extrusion was present in six (23%) of 26 LMRTs and five (2.2%) of 231 patients with normal meniscus roots (P<.001). Complex or deep radial tears were found in three of five cases of lateral meniscus extrusion and normal root. The MFL was not observed in five (19%) of 26 studies of an LMRT. Among these 26 studies of an LMRT, lateral meniscus extrusion was identified in three (14%) of 21 cases in which the MFL was intact and in three (60%) of five cases in which the MFL was not identified (P<.03). Prevalence of an extruded meniscus was seven (88%) of eight for an MMRT and six (23%) of 26 for an LMRT (P=.001). CONCLUSION: Prevalence of LMRTs is greater than that of MMRTs in patients with an ACL tear. LMRTs and complex and radial tears are associated with lateral meniscus extrusion; an absent MFL is more prevalent in patients with LMRTs and when the meniscus is extruded.

Disability and quality of life in Canadian aboriginal and non-aboriginal diabetic lower-extremity amputees.

OBJECTIVE: To compare and contrast disability and quality of life (QOL) in Aboriginal and non-Aboriginal subjects with diabetes who had lower-extremity amputation (LEA) and were living in urban and rural communities in Canada. DESIGN: Descriptive study using an interviewer-administered questionnaire and hospital medical record review. SETTING: Tertiary care center. PARTICIPANTS: Forty-four diabetic subjects (minimum age, 18 y) not receiving dialysis, including 21 Aboriginal (8 urban, 13 rural) and 23 non-Aboriginal (16 urban, 7 rural) subjects. Subjects were living in their current residence and had undergone LEA above the level of the ankle 6 months or more before interview. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Qualitative and quantitative data about symptoms, impairment, and QOL. RESULTS: Aboriginal subjects were younger than non-Aboriginal subjects at the time of diabetes diagnosis (Aboriginal, 42+/-10 y; non-Aboriginal, 52+/-14 y; P<.005) and first major LEA (Aboriginal, 57+/-7 y; non-Aboriginal, 64+/-11 y; P<.015). All subjects received rehabilitation after amputation. More rural non-Aboriginal subjects (83%) used their prosthesis both in and outside the home for all movements than other subjects (P<.048). Rural non-Aboriginal subjects had the lowest and urban non-Aboriginal subjects had the highest frequency of walking-aid use outside the home. Assistance with personal care was required by a minority of subjects, but assistance with daily housework was required by the majority of subjects. Qualitative analysis revealed that participants were, in most cases, comfortable with their postamputation life. CONCLUSIONS: Although the majority of participants in this study generally felt satisfied with their current status, major functional changes were noted after LEA that had a large negative impact on QOL.