The human intestine houses a dense microbial ecosystem in which the struggle for nutrients creates a continual and dynamic selective force. Host-produced mucus glycans provide a ubiquitous source of ...carbon and energy for microbial species. Not surprisingly, many gut resident bacteria have become highly adapted to efficiently consume numerous distinct structures present in host glycans. We propose that sophistication in mucus consumption is a trait most likely to be found in gut residents that have co-evolved with hosts, microbes that have adapted to the complexity associated with the host glycan landscape.
Massive present-day early-type (elliptical and lenticular) galaxies probably gained the bulk of their stellar mass and heavy elements through intense, dust-enshrouded starbursts--that is, increased ...rates of star formation--in the most massive dark-matter haloes at early epochs. However, it remains unknown how soon after the Big Bang massive starburst progenitors exist. The measured redshift (z) distribution of dusty, massive starbursts has long been suspected to be biased low in z owing to selection effects, as confirmed by recent findings of systems with redshifts as high as ~5 (refs 2-4). Here we report the identification of a massive starburst galaxy at z = 6.34 through a submillimetre colour-selection technique. We unambiguously determined the redshift from a suite of molecular and atomic fine-structure cooling lines. These measurements reveal a hundred billion solar masses of highly excited, chemically evolved interstellar medium in this galaxy, which constitutes at least 40 per cent of the baryonic mass. A 'maximum starburst' converts the gas into stars at a rate more than 2,000 times that of the Milky Way, a rate among the highest observed at any epoch. Despite the overall downturn in cosmic star formation towards the highest redshifts, it seems that environments mature enough to form the most massive, intense starbursts existed at least as early as 880 million years after the Big Bang.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The authors describe the design and implementation of a large multiethnic cohort established to study diet and cancer in the United States. They detail the source of the subjects, sample size, ...questionnaire development, pilot work, and approaches to future analyses. The cohort consists of 215,251 adult men and women (age 45–75 years at baseline) living in Hawaii and in California (primarily Los Angeles County) with the following ethnic distribution: African-American (16.3%), Latino (22.0%), Japanese-American (26.4%), Native Hawaiian (6.5%), White (22.9%), and other ancestry (5.8%). From 1993 to 1996, participants entered the cohort by completing a 26-page, self-administered mail questionnaire that elicited a quantitative food frequency history, along with demographic and other information. Response rates ranged from 20% in Latinos to 49% in Japanese-Americans. As expected, both within and among ethnic groups, the questionnaire data show substantial variations in dietary intakes (nutrients as well as foods) and in the distributions of non-dietary risk factors (including smoking, alcohol consumption, obesity, and physical activity). When compared with corresponding ethnic-specific cancer incidence rates, the findings provide tentative support for several current dietary hypotheses. As sufficient numbers of cancer cases are identified through surveillance of the cohort, dietary and other hypotheses will be tested in prospective analyses. Am J Epidemiol 2000;151:346–57.
The flyby of Pluto and Charon by the New Horizons spacecraft provided high-resolution images of cratered surfaces embedded in the Kuiper belt, an extensive region of bodies orbiting beyond Neptune. ...Impact craters on Pluto and Charon were formed by collisions with other Kuiper belt objects (KBOs) with diameters from ~40 kilometers to ~300 meters, smaller than most KBOs observed directly by telescopes. We find a relative paucity of small craters ≲13 kilometers in diameter, which cannot be explained solely by geological resurfacing. This implies a deficit of small KBOs (≲1 to 2 kilometers in diameter). Some surfaces on Pluto and Charon are likely ≳4 billion years old, thus their crater records provide information on the size-frequency distribution of KBOs in the early Solar System.
Autologous breast reconstruction has been noted in the literature to provide superior aesthetic outcomes and patient satisfaction. Additionally, free perforator flap tissue transfer has the potential ...for lower abdominal donor site morbidity. However, it has been noted that the percentage of women who are undergoing autologous breast reconstruction in the United States is decreasing. Factors related to the technical difficulty, prolonged operative times, and decreasing reimbursement have been implicated as the causes.
A retrospective review of electronic medical records over a 5-year period was performed with evaluation of 77 autologous breast reconstructions at a single institution. Patient demographics, comorbidities, number of surgeons involved, operative times, length of stay, and postoperative complications were measured. Wilcoxon rank-sum, Pearson's chi-squared, and proportional odds likelihood ratio tests were performed to compare continuous, categorical, and ordinal outcomes, respectively. Propensity score weighting was used to adjust for presurgical covariates and laterality.
Operative time and length of stay were both significantly lower in the two- versus the single-microsurgeon groups in the unadjusted setting. When covariates and laterality were adjusted for, operative times still remained significantly shorter in the two-microsurgeon group; there were no differences in complications.
Based on our findings, we propose that the two-microsurgeon approach can be utilized in more time-consuming microsurgical cases, such as autologous breast reconstruction, to safely decrease operative times and potentially alleviate surgeon fatigue, reduce operative costs, and thus increase overall surgeon productivity.
Abstract
BACKGROUND
Studies have shown that self-monitoring of blood pressure (BP) is effective when combined with co-interventions, but its efficacy varies in the presence of some co-morbidities. ...This study examined whether self-monitoring can reduce clinic BP in patients with hypertension-related co-morbidity.
METHODS
A systematic review was conducted of articles published in Medline, Embase, and the Cochrane Library up to January 2018. Randomized controlled trials of self-monitoring of BP were selected and individual patient data (IPD) were requested. Contributing studies were prospectively categorized by whether they examined a low/high-intensity co-intervention. Change in BP and likelihood of uncontrolled BP at 12 months were examined according to number and type of hypertension-related co-morbidity in a one-stage IPD meta-analysis.
RESULTS
A total of 22 trials were eligible, 16 of which were able to provide IPD for the primary outcome, including 6,522 (89%) participants with follow-up data. Self-monitoring was associated with reduced clinic systolic BP compared to usual care at 12-month follow-up, regardless of the number of hypertension-related co-morbidities (−3.12 mm Hg, 95% confidence intervals −4.78, −1.46 mm Hg; P value for interaction with number of morbidities = 0.260). Intense interventions were more effective than low-intensity interventions in patients with obesity (P < 0.001 for all outcomes), and possibly stroke (P < 0.004 for BP control outcome only), but this effect was not observed in patients with coronary heart disease, diabetes, or chronic kidney disease.
CONCLUSIONS
Self-monitoring lowers BP regardless of the number of hypertension-related co-morbidities, but may only be effective in conditions such obesity or stroke when combined with high-intensity co-interventions.
The distribution of medium‐scale irregularities in the total ion density at the equator is investigated. In the scale size range between 10 and 400 km, it is found that, as expected, these ...irregularities preferentially appear near 2100 local time (LT) in longitude regions that are selected by season according to an alignment between the magnetic meridian and the sunset terminator. However, these irregularities have a maximum occurrence frequency in the postmidnight sector and do not conform to the expected behavior seen for irregularities that appear after sunset. We suggest that the postmidnight peak in the occurrence frequency for these irregularities arose from the weak vertical drifts that prevail in the afternoon and evening during a prolonged solar minimum. It is also suggested that the observed longitude and seasonal dependence in the peak occurrence frequency is influenced by seeding from tropospheric sources, and therefore responds to the seasonal variations in the colocation of the magnetic equator and the Intertropical Convergence Zone. The irregularities appear throughout the nighttime period when the background density is declining rapidly. Thus, despite the postmidnight maximum in occurrence frequency, the maximum absolute perturbation density, most likely to be responsible for radio scintillation, occurs in the premidnight sector.
Background There is a genetic contribution to the risk of ventricular arrhythmias in survivors of acute coronary syndromes (ACS). We wished to explore the role of 33 candidate single nucleotide ...polymorphisms (SNPs) in prolonged repolarization and sudden death in patients surviving ACS. Methods A total of 2,139 patients (1680 white ethnicity) surviving an admission for ACS were enrolled in the prospective Coronary Disease Cohort Study. Extensive clinical, echocardiographic, and neurohormonal data were collected for 12 months, and clinical events were recorded for a median of 5 years. Each SNP was assessed for association with sudden cardiac death (SCD)/cardiac arrest (CA) and prolonged repolarization at 3 time-points: index admission, 1 month, and 12 months postdischarge. Results One hundred six SCD/CA events occurred during follow-up (6.3%). Three SNPs from 3 genes (rs17779747 KCNJ2 , rs876188 C14orf64 , rs3864180 GPC5 ) were significantly associated with SCD/CA in multivariable models (after correction for multiple testing); the minor allele of rs17779747 with a decreased risk (hazard ratio HR 0.68 per copy of the minor allele, 95% CI 0.50-0.92, P = .012), and rs876188 and rs386418 with an increased risk (HR 1.52 95% CI 1.10-2.09, P = .011 and HR 1.34 95% CI 1.04-1.82, P = .023, respectively). At 12 months postdischarge, rs10494366 and rs12143842 ( NOS1AP ) were significant predictors of prolonged repolarization (HR 1.32 95% CI 1.04-1.67, P = .022 and HR 1.30 95% CI 1.01-1.66, P = .038, respectively), but not at earlier time-points. Conclusion Three SNPs were associated with SCD/CA. Repolarization time was associated with variation in the NOS1AP gene. This study demonstrates a possible role for SNPs in risk stratification for arrhythmic events after ACS.
ABSTRACT
Airborne observations from four flights during the 2008 Indirect and Semi‐Direct Aerosol Campaign (ISDAC) are used to examine some cloud‐free optical, physical, and chemical properties of ...aerosol particles in the springtime Arctic troposphere. The number concentrations of particles larger than 0.12 µm (Na>120), important for light extinction and cloud droplet formation, ranged from 15 to 2260 cm−3, with the higher Na>120 cases dominated by measurements from two flights of long‐range transported biomass burning (BB) aerosols. The two other flights examined here document a relatively clean aerosol and an Arctic Haze aerosol impacted by larger particles largely composed of dust. For observations from the cleaner case and the BB cases, the particle light scattering coefficients at low relative humidity (RH<20%) increased nonlinearly with increasing Na>120, driven mostly by an increase in mean sizes of particles with increasing Na>120 (BB cases). For those three cases, particle light absorption coefficients also increased nonlinearly with increasing Na>120 and linearly with increasing submicron particle volume concentration. In addition to black carbon, brown carbon was estimated to have increased light absorption coefficients by 27% (450 nm wavelength) and 14% (550 nm) in the BB cases. For the case with strong dust influence, the absorption relative to submicron particle volume was small compared with the other cases. There was a slight gradient of Passive Cavity Aerosol Spectrometer Probe (PCASP) mean volume diameter (MVD) towards smaller sizes with increasing height, which suggests more scavenging of the more elevated particles, consistent with a typically longer lifetime of particles higher in the atmosphere. However, in approximately 10% of the cases, the MVD increased (>0.4 µm) with increasing altitude, suggesting transport of larger fine particle mass (possibly coarse particle mass) at high levels over the Arctic. This may be because of transport of larger particles at higher elevations and relatively slow deposition to the surface.
It is widely believed that a defining characteristic of ionic liquids (or low-temperature molten salts) is that they exert no measurable vapour pressure, and hence cannot be distilled. Here we ...demonstrate that this is unfounded, and that many ionic liquids can be distilled at low pressure without decomposition. Ionic liquids represent matter solely composed of ions, and so are perceived as non-volatile substances. During the last decade, interest in the field of ionic liquids has burgeoned, producing a wealth of intellectual and technological challenges and opportunities for the production of new chemical and extractive processes, fuel cells and batteries, and new composite materials. Much of this potential is underpinned by their presumed involatility. This characteristic, however, can severely restrict the attainability of high purity levels for ionic liquids (when they contain poorly volatile components) in recycling schemes, as well as excluding their use in gas-phase processes. We anticipate that our demonstration that some selected families of commonly used aprotic ionic liquids can be distilled at 200-300 °C and low pressure, with concomitant recovery of significant amounts of pure substance, will permit these currently excluded applications to be realized.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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