SciCombinator

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Concept: Remainder

271

We compared the impact of media vs. direct exposure on acute stress response to collective trauma. We conducted an Internet-based survey following the Boston Marathon bombings between April 29 and May 13, 2013, with representative samples of residents from Boston (n = 846), New York City (n = 941), and the remainder of the United States (n = 2,888). Acute stress symptom scores were comparable in Boston and New York [regression coefficient (b) = 0.43; SE = 1.42; 95% confidence interval (CI), -2.36, 3.23], but lower nationwide when compared with Boston (b = -2.21; SE = 1.07; 95% CI, -4.31, -0.12). Adjusting for prebombing mental health (collected prospectively), demographics, and prior collective stress exposure, six or more daily hours of bombing-related media exposure in the week after the bombings was associated with higher acute stress than direct exposure to the bombings (continuous acute stress symptom total: media exposure b = 15.61 vs. direct exposure b = 5.69). Controlling for prospectively collected prebombing television-watching habits did not change the findings. In adjusted models, direct exposure to the 9/11 terrorist attacks and the Sandy Hook School shootings were both significantly associated with bombing-related acute stress; Superstorm Sandy exposure wasn’t. Prior exposure to similar and/or violent events may render some individuals vulnerable to the negative effects of collective traumas. Repeatedly engaging with trauma-related media content for several hours daily shortly after collective trauma may prolong acute stress experiences and promote substantial stress-related symptomatology. Mass media may become a conduit that spreads negative consequences of community trauma beyond directly affected communities.

Concepts: United States, New York City, Massachusetts, New England, Marathon, Remainder, September 11 attacks, Acute stress reaction

187

Lifetime risk is a relatively straightforward measure used to communicate disease burden, representing the cumulative risk of an outcome during the remainder of an individual’s life starting from a disease-free index age. We estimated the lifetime risk of diabetes among men and women in both First Nations and non-First Nations populations using a cohort of adults in a single Canadian province.

Concepts: Alberta, Canada, Nova Scotia, Remainder, Ontario, Quebec, Northwest Territories, Saskatchewan

37

We examine the temporal evolution of digital communication activity relating to the American anti-capitalist movement Occupy Wall Street. Using a high-volume sample from the microblogging site Twitter, we investigate changes in Occupy participant engagement, interests, and social connectivity over a fifteen month period starting three months prior to the movement’s first protest action. The results of this analysis indicate that, on Twitter, the Occupy movement tended to elicit participation from a set of highly interconnected users with pre-existing interests in domestic politics and foreign social movements. These users, while highly vocal in the months immediately following the birth of the movement, appear to have lost interest in Occupy related communication over the remainder of the study period.

Concepts: Sociology, Natural number, Integer, Remainder, Social movement, Twitter, ASCII, Activism

34

Amyloid-β (Aβ) is present in humans as a 39- to 42-amino acid residue metabolic product of the amyloid precursor protein. Although the two predominant forms, Aβ(1-40) and Aβ(1-42), differ in only two residues, they display different biophysical, biological, and clinical behavior. Aβ(1-42) is the more neurotoxic species, aggregates much faster, and dominates in senile plaque of Alzheimer’s disease (AD) patients. Although small Aβ oligomers are believed to be the neurotoxic species, Aβ amyloid fibrils are, because of their presence in plaques, a pathological hallmark of AD and appear to play an important role in disease progression through cell-to-cell transmissibility. Here, we solved the 3D structure of a disease-relevant Aβ(1-42) fibril polymorph, combining data from solid-state NMR spectroscopy and mass-per-length measurements from EM. The 3D structure is composed of two molecules per fibril layer, with residues 15-42 forming a double-horseshoe-like cross-β-sheet entity with maximally buried hydrophobic side chains. Residues 1-14 are partially ordered and in a β-strand conformation, but do not display unambiguous distance restraints to the remainder of the core structure.

Concepts: Alzheimer's disease, Protein, Biology, Nuclear magnetic resonance, Neurology, Dementia, Amyloid precursor protein, Remainder

30

Objective: Sodium benzoate, a common additive in popular beverages, has recently been linked to ADHD. This research examined the relationship between sodium benzoate-rich beverage ingestion and symptoms related to ADHD in college students. Method: College students (N = 475) completed an anonymous survey in class in fall 2010. The survey assessed recent intake of a noninclusive list of sodium benzoate-rich beverages and ADHD-related symptoms using a validated screener. Results: Sodium benzoate-rich beverage intake was significantly associated with ADHD-related symptoms (p = .001), and significance was retained after controlling for covariates. Students scoring ≥4 on the screener (scores that may be consistent with ADHD; n = 67) reported higher intakes (34.9 ± 4.4 servings/month) than the remainder of the sample (16.7 ± 1.1 servings/month). Conclusion: These data suggest that a high intake of sodium benzoate-rich beverages may contribute to ADHD-related symptoms in college students and warrants further investigation.

Concepts: Report, Benzoic acid, Alcoholic beverage, Remainder, Intake, Drink, The Colbert Report, Beverages

29

We conducted a model-based assessment of changes in permafrost area and carbon storage for simulations driven by RCP4.5 and RCP8.5 projections between 2010 and 2299 for the northern permafrost region. All models simulating carbon represented soil with depth, a critical structural feature needed to represent the permafrost carbon-climate feedback, but that is not a universal feature of all climate models. Between 2010 and 2299, simulations indicated losses of permafrost between 3 and 5 million km2for the RCP4.5 climate and between 6 and 16 million km2for the RCP8.5 climate. For the RCP4.5 projection, cumulative change in soil carbon varied between 66-Pg C (1015-g carbon) loss to 70-Pg C gain. For the RCP8.5 projection, losses in soil carbon varied between 74 and 652 Pg C (mean loss, 341 Pg C). For the RCP4.5 projection, gains in vegetation carbon were largely responsible for the overall projected net gains in ecosystem carbon by 2299 (8- to 244-Pg C gains). In contrast, for the RCP8.5 projection, gains in vegetation carbon were not great enough to compensate for the losses of carbon projected by four of the five models; changes in ecosystem carbon ranged from a 641-Pg C loss to a 167-Pg C gain (mean, 208-Pg C loss). The models indicate that substantial net losses of ecosystem carbon would not occur until after 2100. This assessment suggests that effective mitigation efforts during the remainder of this century could attenuate the negative consequences of the permafrost carbon-climate feedback.

Concepts: Biodiversity, Climate, Soil, Ecosystem, Climate change, Remainder, Global warming, Projection

27

BACKGROUND: It is believed that patients with an ankle arthrodesis (AA) have better outcomes than after a tibiotalocalcaneal (TTC) arthrodesis due to preservation of subtalar motion. However, there are no studies comparing actual functional outcomes and patient satisfaction between AA and TTC arthrodesis. METHODS: We retrospectively analyzed patient satisfaction and functional outcomes of patients after an AA and TTC arthrodesis using a postal survey. A total of 173 patients who underwent TTC and 100 AA patients from 2002 to 2010 were identified with a minimum of 24 months follow-up. In all, 53 AA and 64 TTC arthrodesis patients were included in the study, with the remainder lost to follow-up. A return to activity questionnaire and SF-12 scores were used to compare functional outcomes. The mean follow-up time was 63 months. RESULTS: Both groups showed good outcomes with a low visual analogue pain score (2.7 for AA and 2.8 for TTC), high satisfaction score (90.6% for AA and 87.5% for TTC), and return to work (77.4% for AA and 73.0% for TTC). In all, 84.6% of AA and 81.0% of TTC patients would have the surgery again. There were no significant differences between the 2 groups for these parameters. However, when asked if their desired activity level was met, fewer AA patients met their desired level (58.5% for AA and 66.5% for TTC, P = .02). AA patients were also more likely to feel their level was unmet due to the foot and ankle (85.6% for AA vs 25.7% for TTC, P < .001). CONCLUSIONS: Both AA and TTC arthrodesis were associated with good functional outcomes and satisfaction. AA patients had higher postoperative activity expectations and were less likely to meet them. When they failed to meet these expectations, they were much more likely to attribute it to their operated ankle. We believe it is because of the different ways the 2 groups of patients are counseled preoperatively, which highlights the importance of managing patient expectations. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Concepts: Patient, Foot, Remainder, Arthrodesis

25

Neonatal circumcision in patients with severe haemophilia has not been well studied. We performed a survey of paediatric haematologists from Hemophilia Treatment Centers (HTC) across the United States to better understand the attitudes toward and management of neonatal circumcision in haemophilia patients. Response rate to our survey was 40% (n = 64/159). Thirty-eight percent of respondents (n = 24) said that they would allow this procedure in the newborn period but in many cases this was against medical advice. The most reported concern regarding neonatal circumcision in haemophilia patients was the risk of development of an inhibitor (n = 25; 39%) followed by the concern for bleeding (n = 22; 34%) and issues related to vascular access in the neonate (n = 11; 17%). All respondents recommended at least one preprocedure dose of factor replacement. Twenty-two percent (n = 14) of respondents did not use more than one dose of factor replacement but 32% (n = 21) used 1-2 postoperative doses. The remainder of paediatric haematologists surveyed recommended between 3-5 (16%; n = 10) and 6-10 (3%, n = 2) additional days postoperatively. There was wide variation in both techniques of circumcision as well as adjuvant haemostatic agents used. Only 22% of respondents said that they had an established protocol for management of circumcision in the newborn haemophilia patient. These survey results highlight the need for evidence-based guidelines regarding the optimal management of circumcision in neonates with severe haemophilia.

Concepts: Infant, United States, Milk, Physician, Infant mortality, Pediatrics, Haemophilia A, Remainder

15

Hydroxyethyl Starch or Saline for Fluid Resuscitation in Intensive Care Original Article, N Engl J Med 2012;367:1901-1911. In Table 2 (page 1907), the “Days receiving mechanical ventilation” and “Days receiving renal-replacement therapy” rows in the stub column should have included a footnote marker, and the following footnote should have been added: “Data are presented for the proportion of patients who received the intervention.” In the remainder of the table (the five rows below “Treatment-related adverse events”), the values were incorrect: from left to right, the values for Any event - no./total no. (%) should have been 180/3871 (4.6) and 95/2879 (3.3) (with 0.006 in the P Value column); for Pruritis, 137/3871 (3.5) and 73/2879 (2.5); for Skin rash, 34/3871 (0.9) and 16/2879 (0.6); for Other, 9/3871 (0.2) and 6/2879 (0.2); and for Serious adverse events - no./total no., 2/3871 (0.1) and 2/2879 (0.1) (with 0.77 in the P Value column). The article is correct at NEJM.org.

Concepts: Value added, Culture, Starch, Value, Remainder, Rash, The Table

11

Few studies describe the primary drivers influencing soil organic carbon (SOC) stocks and the distribution of carbon © fractions in agricultural systems from semi-arid regions; yet these soils comprise one fifth of the global land area. Here we identified the primary drivers for changes in total SOC and associated particulate (POC), humus (HOC) and resistant (ROC) organic C fractions for 1347 sample points in the semi-arid agricultural region of Western Australia. Total SOC stock (0-0.3 m) varied from 4 to 209 t C ha(-1) with 79% of variation explained by measured variables. The proportion of C in POC, HOC and ROC fractions averaged 28%, 45% and 27% respectively. Climate (43%) and land management practices (32%) had the largest relative influence on variation in total SOC. Carbon accumulation was constrained where average daily temperature was above 17.2 °C and annual rainfall below 450 mm, representing approximately 42% of the 197,300 km(2) agricultural region. As such large proportions of this region are not suited to C sequestration strategies. For the remainder of the region a strong influence of management practices on SOC indicate opportunities for C sequestration strategies associated with incorporation of longer pasture phases and adequate fertilisation.

Concepts: Agriculture, Soil, Nitrogen, Humus, Remainder, Organic matter, Compost, Manure