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This paper summarizes a multi-state, multi-year study assessing the potential for local agriculture in northern New England. While largely rural, this region's agricultural sector differs greatly from the rest of the United States, and demand for locally produced food has been increasing. To assess this unique economic landscape, researchers and Cooperative Extension at the Universities of Maine, New Hampshire, and Vermont investigated four key areas: (1) local food capacities, (2) constraints to agricultural expansion, (3) consumer preferences for local and organic produce, and (4) the role of intermediaries as alternative local food outlets. The project included input from local farmers, Extension members, restaurants, and the general public. We present the four research areas in a sequential, overlapping fashion. The timing of our research was such that each step in the process informed the next and can be used as a template for assessing a region's potential for local agricultural production.
The staggered renewal of parliamentary mandates is widespread in upper chambers, yet little understood. Comparative work has found that all members of a chamber are affected by upcoming elections, not merely those whose terms are up for renewal. In this study, we explore for which activities, and under which conditions, staggered membership renewal is associated with class-specific parliamentary activity, defined as systematically differing behaviour across two or more classes of members. We examine these questions with data on the French Senate. Drawing on insights from the study of political business cycles, legislative cycles, and previous scholarship on staggering, the article shows that behaviour varies over the course of senators’ mandates, and that class-specific behaviour exists. However, staggering produces a different pattern of parliamentary activity than might be expected: proximity to elections reduces parliamentary activity of the class of senators facing re-election; by contrast, senators ‘not up next’ become more active. This effect, we argue, reflects the electoral system under which senators are elected.
Antibiotics are overprescribed for acute respiratory tract infections (ARIs). Guidelines provide criteria to determine which patients should receive antibiotics. We assessed congruence between documentation of ARI diagnostic and treatment practices with guideline recommendations, treatment appropriateness, and outcomes.
A multicenter quality improvement evaluation was conducted in 28 Veterans Affairs facilities. We included visits for pharyngitis, rhinosinusitis, bronchitis, and upper respiratory tract infections (URI-NOS) that occurred during the 2015–2016 winter season. A manual record review identified complicated cases, which were excluded. Data were extracted for visits meeting criteria, followed by analysis of practice patterns, guideline congruence, and outcomes.
Of 5,740 visits, 4,305 met our inclusion criteria: pharyngitis (n = 558), rhinosinusitis (n = 715), bronchitis (n = 1,155), URI-NOS (n = 1,475), or mixed diagnoses (>1 ARI diagnosis) (n = 402). Antibiotics were prescribed in 68% of visits: pharyngitis (69%), rhinosinusitis (89%), bronchitis (86%), URI-NOS (37%), and mixed diagnosis (86%). Streptococcal diagnostic testing was performed in 33% of pharyngitis visits; group A Streptococcus was identified in 3% of visits. Streptococcal tests were ordered less frequently for patients who received antibiotics (28%) than those who did not receive antibiotics 44%; P < .01). Although 68% of visits for rhinosinusitis had documentation of symptoms, only 32% met diagnostic criteria for antibiotics. Overall, 39% of patients with uncomplicated ARIs received appropriate antibiotic management. The proportion of 30-day return visits for ARI care was similar for appropriate (11%) or inappropriate (10%) antibiotic management (P = .22).
Antibiotics were prescribed in most uncomplicated ARI visits, indicating substantial overuse. Practice was frequently discordant with guideline diagnostic and treatment recommendations.
To examine variation in antibiotic coverage and detection of resistant pathogens in community-onset pneumonia.
A total of 128 hospitals in the Veterans Affairs health system.
Hospitalizations with a principal diagnosis of pneumonia from 2009 through 2010.
We examined proportions of hospitalizations with empiric antibiotic coverage for methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa (PAER) and with initial detection in blood or respiratory cultures. We compared lowest- versus highest-decile hospitals, and we estimated adjusted probabilities (AP) for patient- and hospital-level factors predicting coverage and detection using hierarchical regression modeling.
Among 38,473 hospitalizations, empiric coverage varied widely across hospitals (MRSA lowest vs highest, 8.2% vs 42.0%; PAER lowest vs highest, 13.9% vs 44.4%). Detection rates also varied (MRSA lowest vs highest, 0.5% vs 3.6%; PAER lowest vs highest, 0.6% vs 3.7%). Whereas coverage was greatest among patients with recent hospitalizations (AP for anti-MRSA, 54%; AP for anti-PAER, 59%) and long-term care (AP for anti-MRSA, 60%; AP for anti-PAER, 66%), detection was greatest in patients with a previous history of a positive culture (AP for MRSA, 7.9%; AP for PAER, 11.9%) and in hospitals with a high prevalence of the organism in pneumonia (AP for MRSA, 3.9%; AP for PAER, 3.2%). Low hospital complexity and rural setting were strong negative predictors of coverage but not of detection.
Hospitals demonstrated widespread variation in both coverage and detection of MRSA and PAER, but probability of coverage correlated poorly with probability of detection. Factors associated with empiric coverage (eg, healthcare exposure) were different from those associated with detection (eg, microbiology history). Providing microbiology data during empiric antibiotic decision making could better align coverage to risk for resistant pathogens and could promote more judicious use of broad-spectrum antibiotics.
To detail the activities of the Veterans Health Administration (VHA) Antimicrobial Stewardship Initiative and evaluate outcomes of the program.
The VHA is a large integrated healthcare system serving approximately 6 million individuals annually at more than 140 medical facilities.
Utilization of nationally developed resources, proportional distribution of antibiotics, changes in stewardship practices and patient safety measures were reported. In addition, inpatient antimicrobial use was evaluated before and after implementation of national stewardship activities.
Nationally developed stewardship resources were well utilized, and many stewardship practices significantly increased, including development of written stewardship policies at 92% of facilities by 2015 (P<.05). While the proportional distribution of antibiotics did not change, inpatient antibiotic use significantly decreased after VHA Antimicrobial Stewardship Initiative activities began (P<.0001). A 12% decrease in antibiotic use was noted overall. The VHA has also noted significantly declining use of antimicrobials prescribed for resistant Gram-negative organisms, including carbapenems, as well as declining hospital readmission and mortality rates. Concurrently, the VHA reported decreasing rates of Clostridium difficile infection.
The VHA National Antimicrobial Stewardship Initiative includes continuing education, disease-specific guidelines, and development of example policies in addition to other highly utilized resources. While no specific ideal level of antimicrobial utilization has been established, the VHA has shown that improving antimicrobial usage in a large healthcare system may be achieved through national guidance and resources with local implementation of antimicrobial stewardship programs.
To estimate avoidable intravenous (IV) fluoroquinolone use in Veterans Affairs (VA) hospitals.
A retrospective analysis of bar code medication administration (BCMA) data.
Acute care wards of 128 VA hospitals throughout the United States.
Data were analyzed for all medications administered on acute care wards between January 1, 2006, and December 31, 2010. Patient-days receiving therapy were expressed as fluoroquinolone-days (FD) and divided into intravenous (IV; all doses administered intravenously) and oral (PO; at least one dose administered per os) FD. We assumed IV fluoroquinolone use to be potentially avoidable on a given IV FD when there was at least 1 other medication administered via the enteral route.
Over the entire study period, 884,740 IV and 830,572 PO FD were administered. Overall, avoidable IV fluoroquinolone use accounted for 46.8% of all FD and 90.9% of IV FD. Excluding the first 2 days of all IV fluoroquinolone courses and limiting the analysis to the non-ICU setting yielded more conservative estimates of avoidable IV use: 20.9% of all FD and 45.9% of IV FD. Avoidable IV use was more common for levofloxacin and more frequent in the ICU setting. There was a moderate correlation between avoidable IV FD and total systemic antibiotic use (r = 0.32).
Unnecessary IV fluoroquinolone use seems to be common in the VA system, but important variations exist between facilities. Antibiotic stewardship programs could focus on this patient safety issue as a “low-hanging fruit” to increase awareness of appropriate antibiotic use.
Clinical manifestations of lactase (LCT) deficiency include intestinal and extra-intestinal symptoms. Lactose hydrogen breath test (H2-BT) is considered the gold standard to evaluate LCT deficiency (LD). Recently, the single-nucleotide polymorphism C/T− 13 910 has been associated with LD. The objectives of the present study were to evaluate the agreement between genetic testing of LCT C/T− 13 910 and lactose H2-BT, and the diagnostic value of extended symptom assessment. Of the 201 patients included in the study, 194 (139 females; mean age 38, range 17–79 years, and 55 males, mean age 38, range 18–68 years) patients with clinical suspicion of LD underwent a 3–4 h H2-BT and genetic testing for LCT C/T− 13 910. Patients rated five intestinal and four extra-intestinal symptoms during the H2-BT and then at home for the following 48 h. Declaring H2-BT as the gold standard, the CC− 13 910 genotype had a sensitivity of 97 % and a specificity of 95 % with a κ of 0·9 in diagnosing LCT deficiency. Patients with LD had more intense intestinal symptoms 4 h following the lactose challenge included in the H2-BT. We found no difference in the intensity of extra-intestinal symptoms between patients with and without LD. Symptom assessment yielded differences for intestinal symptoms abdominal pain, bloating, borborygmi and diarrhoea between 120 min and 4 h after oral lactose challenge. Extra-intestinal symptoms (dizziness, headache and myalgia) and extension of symptom assessment up to 48 h did not consistently show different results. In conclusion, genetic testing has an excellent agreement with the standard lactose H2-BT, and it may replace breath testing for the diagnosis of LD. Extended symptom scores and assessment of extra-intestinal symptoms have limited diagnostic value in the evaluation of LD.
Investigation into the early hydration of Portland cement was performed by in situ X-ray diffraction (XRD). Technical white cement was used for the XRD analysis on a D5000 diffractometer (Siemens). All diffraction patterns of the in situ measurement which were recorded up to 22 h of hydration at defined temperatures were analyzed by Rietveld refinement. The resulting phase composition was transformed with respect to free water and C-S-H leading to the total composition of the cement paste. The hydration reactions can be observed by dissolution of clinker phases as well as by the formation of the hydrate phases ettringite and portlandite. With increasing temperatures the reactions proceed faster. The formation of ettringite is directly influenced by the rate of dissolution of anhydrite and tricalcium aluminate (C3A). The beginning of the main period of hydration is marked by the start of portlandite formation. The experiments point out that a quantitative phase analysis of the cement hydration is feasible with standard laboratory diffractometers.
Charles Darwin's (1859) theory of evolution by natural selection is among the most important scientific theories and is the most important theory in all of the life sciences. Some have even argued that the principles of Darwin's theory can explain the laws of physics and the organization of the universe (e.g., Dennett, 1995). Although Darwin's name is synonymous with evolution (which refers to the modification of traits with descent), philosophers and scholars were thinking about evolution long before Darwin. In fact, one of the first discussions of evolution pre-dates Darwin by two and a half millennia. Anaximander, a Greek philosopher, suggested that “in water the first animal arose covered with spiny skin, and with the lapse of time some crawled onto dry land and breaking off their skins in a short time they survived.” Even Darwin's grandfather, Erasmus Darwin, wrote of common ancestry and speciation. What Charles Darwin (1859) provided, however, was a viable working mechanism of evolution: natural selection. Darwinian selection has become the centerpiece of biology, and in the last few decades, many psychologists and anthropologists have recognized the value of employing an evolutionary perspective in their work (for early writings see Barkow, Cosmides, and Tooby, 1992; Chagnon and Irons, 1979; Daly and Wilson, 1983; Symons, 1979). With a focus on evolved psychological mechanisms and their information processing, evolutionary psychology has risen as a compelling and fruitful approach to psychological science. This chapter provides an introduction to evolution by natural selection and its modern application to the study of human behavior and cognition.
We propose that middle childhood female ambivalent attachment, given the adaptive problem of uncertainty of future investment, is designed to evoke immediate investment from current caregivers, rather than new investment sources. We suggest greater specificity of strategic attachment solutions to adaptive problems that differ by sex, time, and relationship type.
Mineralogy and Remote Sensing of Rocks, Soil, Dust, and Ices
W. Goetz, Max Planck Institute for Solar System Research Max Planck Str. 2 Katlenburg-Lindau, 37191, Germany,
S. F. Hviid, Max Planck Institute for Solar System Research Max Planck Str. 2 Katlenburg-Lindau, 37191, Germany,
K. M. Kinch, CRSR Cornell University 408 Space Sciences Building Ithaca, NY 13853, USA,
M. B. Madsen, Niels Bohr Institute for Astronomy, University of Copenhagen Universitetsparken 5 Copenhagen, DK-2100, Denmark
The surface and aeolian dust on Mars is rich in iron compounds, and significant quantities of dust have been observed to stick to permanent magnets that are either exposed to the dusty atmosphere, exposed to dust released by grinding into rocks, or inserted into the soil. All successful lander missions to Mars so far have carried permanent magnets of various designs for the purpose of studying dust magnetic properties. The magnetism of the aeolian dust is the result of the presence of magnetite, which apparently derives from mechanical weathering of magnetite-rich surface rocks. A strong correlation between the elements titanium and iron is observed in elemental abundance spectra of dust attracted to permanent-magnet surfaces, suggesting that the magnetite responsible for the magnetization of the dust is actually titanomagnetite. Overall, the dust can be shown to have a saturation magnetization of less than 2 A m2 kg− 1. However, some grains are significantly more magnetic, and by interaction with a permanent magnet it is possible to separate the airborne dust into populations of more and less magnetic grains. Subpopulations attracted to a magnet have been seen to have magnetizations above 7 A m2 kg− 1. The widespread presence of magnetite and other easily oxidized minerals like olivine in rocks and in the global Martian dust imply that the Martian surface has been largely devoid of liquid water for a very long time.
Tamoxifen can be considered a classic ‘pro-drug’, requiring metabolic activation to elicit pharmacological activity. Our findings suggest that both genetic and drug-induced factors that alter CYP2D6 enzyme activity influence the clinical response to tamoxifen. Given the small differences in disease-free survival comparing tamoxifen to third-generation aromatase inhibitors, knowledge of the genetic and environmental factors that influence CYP2D6 enzyme activity may provide a robust tool to individualize the hormonal therapy to breast cancer.
Multilayered and nanostructured coatings of amorphous carbon (DLC), silicon composite multilayers and nanocluster containing films today have great potential for applications as hard coatings, wear reduction layers and as diffusion barriers in biomaterials. Plasma immersion ion implantation and deposition (PIII&D) is a powerful technique to synthesize such films. The quantitative nanoscale analysis of the elemental distribution in such multielemental films and thin film stacks however is demanding.
In this paper it is shown how the high spatial resolution capabilities of energy filtered trans-mission electron microscopy (EFTEM) chemical analysis can be combined with accurate and standard-less concentration determination of ion beam analysis (IBA) techniques like Rutherford Backscattering Spectroscopy (RBS) and Elastic Recoil Detection Analysis (ERDA) to achieve absolute and accurate multielement concentration profiles in complicated nanomaterials.
A study of Si-doped and Mg-doped AlxGa1-xN up to × ∼ 50 % and the characteristics of ultraviolet (UV) light emitting diodes (LEDs) with emission wavelengths at 340 nm and 290 nm are reported. By using grading super-lattices (SLs) before n-type AlGaN growth, surface roughness is much improved. Resistivity of 2.9×10-2 Ωcm and free electron concentrations of 2.9×10 cm- are achieved for n-type Al0.45Ga0.55N. The viability of effective p-type doping is defined by a minimum concentration of Mg required to offset the background impurities and, more importantly, a maximum limit above which inversion domains and structural defects start to nucleate, accompanied by a rapid degradation of electrical transport. Resistivity of 10 Ωcm and free hole concentrations above 1017 cm−3 are achieved for AlxGa1-xN up to × ∼ 50 % within an optimum window of Mg incorporation. Output powers up to 1.5 mW from small area 340 nm LEDs (< 100 μm diameter) and 110 μW from 290 nm LEDs (100 μm diameter) directly off a planar chip have been achieved under DC condition. For large area encapsulated lamp (1×1 mm2 device area and 0.52 mm2 mesa area), output power of 79 mW from 340 nm LEDs and 8.5 mW from 290 nm LEDs are achieved under pulse mode (1kHz, 2% duty factor).