505 research outputs found
Randomized controlled trial of the effect of phytosterols-enriched low-fat milk on lipid profile in Chinese
published_or_final_versio
Brief intervention to promote smoking cessation and improve glycemic control in smokers with type 2 diabetes: a randomized controlled trial
published_or_final_versio
An SU(N) Mott insulator of an atomic Fermi gas realized by large-spin Pomeranchuk cooling
The Hubbard model, containing only the minimum ingredients of nearest
neighbor hopping and on-site interaction for correlated electrons, has
succeeded in accounting for diverse phenomena observed in solid-state
materials. One of the interesting extensions is to enlarge its spin symmetry to
SU(N>2), which is closely related to systems with orbital degeneracy. Here we
report a successful formation of the SU(6) symmetric Mott insulator state with
an atomic Fermi gas of ytterbium (173Yb) in a three-dimensional optical
lattice. Besides the suppression of compressibility and the existence of charge
excitation gap which characterize a Mott insulating phase, we reveal an
important difference between the cases of SU(6) and SU(2) in the achievable
temperature as the consequence of different entropy carried by an isolated
spin. This is analogous to Pomeranchuk cooling in solid 3He and will be helpful
for investigating exotic quantum phases of SU(N) Hubbard system at extremely
low temperatures.Comment: 20 pages, 6 figures, to appear in Nature Physic
The effect of arm training on thermoregulatory responses and calf volume during upper body exercise
The final publication is available at Springer via https://doi.org/10.1007/s00421-014-2842-9.PURPOSE: The smaller muscle mass of the upper body compared to the lower body may elicit a smaller thermoregulatory stimulus during exercise and thus produce novel training-induced thermoregulatory adaptations. Therefore, the principal aim of the study was to examine the effect of arm training on thermoregulatory responses during submaximal exercise. METHODS: Thirteen healthy male participants (Mean ± SD age 27.8 ± 5.0 years, body mass 74.8 ± 9.5 kg) took part in 8 weeks of arm crank ergometry training. Thermoregulatory and calf blood flow responses were measured during 30 min of arm cranking at 60% peak power (W peak) pre-, and post-training and post-training at the same absolute intensity as pre-training. Core temperature and skin temperatures were measured, along with heat flow at the calf, thigh, upper arm and chest. Calf blood flow using venous occlusion plethysmography was performed pre- and post-exercise and calf volume was determined during exercise. RESULTS: The upper body training reduced aural temperature (0.1 ± 0.3 °C) and heat storage (0.3 ± 0.2 J g(-1)) at a given power output as a result of increased whole body sweating and heat flow. Arm crank training produced a smaller change in calf volume post-training at the same absolute exercise intensity (-1.2 ± 0.8% compared to -2.2 ± 0.9% pre-training; P < 0.05) suggesting reduced leg vasoconstriction. CONCLUSION: Training improved the main markers of aerobic fitness. However, the results of this study suggest arm crank training additionally elicits physiological responses specific to the lower body which may aid thermoregulation.Peer reviewedFinal Accepted Versio
Nanoparticles that communicate in vivo to amplify tumour targeting
Author Manuscript: 2012 May 29Nanomedicines have enormous potential to improve the precision of cancer therapy, yet our ability to efficiently home these materials to regions of disease in vivo remains very limited. Inspired by the ability of communication to improve targeting in biological systems, such as inflammatory-cell recruitment to sites of disease, we construct systems where synthetic biological and nanotechnological components communicate to amplify disease targeting in vivo. These systems are composed of ‘signalling’ modules (nanoparticles or engineered proteins) that target tumours and then locally activate the coagulation cascade to broadcast tumour location to clot-targeted ‘receiving’ nanoparticles in circulation that carry a diagnostic or therapeutic cargo, thereby amplifying their delivery. We show that communicating nanoparticle systems can be composed of multiple types of signalling and receiving modules, can transmit information through multiple molecular pathways in coagulation, can operate autonomously and can target over 40 times higher doses of chemotherapeutics to tumours than non-communicating controls.National Cancer Institute (U.S.) (SBMRI Cancer Center Support Grant 5 P30 CA30199-28)National Cancer Institute (U.S.) (MIT CCNE Grant U54 CA119349)National Cancer Institute (U.S.) (Bioengineering Research Partnership Grant 5-R01-CA124427)National Cancer Institute (U.S.) (UCSD CCNE Grant U54 CA 119335)National Science Foundation (U.S.) (Whitaker Graduate Fellowship
Varieties of living things: Life at the intersection of lineage and metabolism
publication-status: Publishedtypes: Articl
Multi-messenger observations of a binary neutron star merger
On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta
Prognostic model to predict postoperative acute kidney injury in patients undergoing major gastrointestinal surgery based on a national prospective observational cohort study.
Background: Acute illness, existing co-morbidities and surgical stress response can all contribute to postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery. The aim of this study was prospectively to develop a pragmatic prognostic model to stratify patients according to risk of developing AKI after major gastrointestinal surgery. Methods: This prospective multicentre cohort study included consecutive adults undergoing elective or emergency gastrointestinal resection, liver resection or stoma reversal in 2-week blocks over a continuous 3-month period. The primary outcome was the rate of AKI within 7 days of surgery. Bootstrap stability was used to select clinically plausible risk factors into the model. Internal model validation was carried out by bootstrap validation. Results: A total of 4544 patients were included across 173 centres in the UK and Ireland. The overall rate of AKI was 14·2 per cent (646 of 4544) and the 30-day mortality rate was 1·8 per cent (84 of 4544). Stage 1 AKI was significantly associated with 30-day mortality (unadjusted odds ratio 7·61, 95 per cent c.i. 4·49 to 12·90; P < 0·001), with increasing odds of death with each AKI stage. Six variables were selected for inclusion in the prognostic model: age, sex, ASA grade, preoperative estimated glomerular filtration rate, planned open surgery and preoperative use of either an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Internal validation demonstrated good model discrimination (c-statistic 0·65). Discussion: Following major gastrointestinal surgery, AKI occurred in one in seven patients. This preoperative prognostic model identified patients at high risk of postoperative AKI. Validation in an independent data set is required to ensure generalizability
Laparoscopy in management of appendicitis in high-, middle-, and low-income countries: a multicenter, prospective, cohort study.
BACKGROUND: Appendicitis is the most common abdominal surgical emergency worldwide. Differences between high- and low-income settings in the availability of laparoscopic appendectomy, alternative management choices, and outcomes are poorly described. The aim was to identify variation in surgical management and outcomes of appendicitis within low-, middle-, and high-Human Development Index (HDI) countries worldwide. METHODS: This is a multicenter, international prospective cohort study. Consecutive sampling of patients undergoing emergency appendectomy over 6 months was conducted. Follow-up lasted 30 days. RESULTS: 4546 patients from 52 countries underwent appendectomy (2499 high-, 1540 middle-, and 507 low-HDI groups). Surgical site infection (SSI) rates were higher in low-HDI (OR 2.57, 95% CI 1.33-4.99, p = 0.005) but not middle-HDI countries (OR 1.38, 95% CI 0.76-2.52, p = 0.291), compared with high-HDI countries after adjustment. A laparoscopic approach was common in high-HDI countries (1693/2499, 67.7%), but infrequent in low-HDI (41/507, 8.1%) and middle-HDI (132/1540, 8.6%) groups. After accounting for case-mix, laparoscopy was still associated with fewer overall complications (OR 0.55, 95% CI 0.42-0.71, p < 0.001) and SSIs (OR 0.22, 95% CI 0.14-0.33, p < 0.001). In propensity-score matched groups within low-/middle-HDI countries, laparoscopy was still associated with fewer overall complications (OR 0.23 95% CI 0.11-0.44) and SSI (OR 0.21 95% CI 0.09-0.45). CONCLUSION: A laparoscopic approach is associated with better outcomes and availability appears to differ by country HDI. Despite the profound clinical, operational, and financial barriers to its widespread introduction, laparoscopy could significantly improve outcomes for patients in low-resource environments. TRIAL REGISTRATION: NCT02179112
Inpatient-Onset Versus Outpatient-Onset ST-Segment-Elevation Myocardial Infarction in Patients With Percutaneous Coronary Intervention: A National Registry Study
BACKGROUND: Compared with patients who develop ST-segment-elevation myocardial infarction (STEMI) outside the hospital and present at the emergency department (outpatient-onset), patients with inpatient-onset STEMI may paradoxically experience a poorer prognosis due to underlying disease, despite the apparent immediate access to acute health care services. METHODS: Patients with first-onset STEMI who underwent percutaneous coronary intervention (PCI) in the Singapore Myocardial Infarction Registry (2007-2020) were included. For patients with inpatient-onset STEMI, the recognition-to-balloon time was measured from symptom onset to PCI. For outpatient-onset STEMI, the recognition-to-balloon time was defined as the sum of the symptom-to-door and door-to-balloon time. Logistic regression was used to identify factors associated with delayed PCI after inpatient-onset STEMI. Cox regression was used to assess 30-day, 1-year, 5-year, and 10-year all-cause and cardiovascular mortality. RESULTS: A total of 19 149 patients, 17 659 (92.2%) outpatient-onset and 1595 (7.8%) inpatient-onset, were included. The median follow-up duration was 6.91 years. Patients with inpatient-onset STEMI were older, more frequently women, nonsmokers, more likely to have comorbidities, less likely to present with typical STEMI symptoms, and more likely to experience delays in PCI than patients with outpatient-onset STEMI within the hospital setting. The independent predictors of delayed PCI for inpatient-onset STEMI were age ≥65 years, diabetes, breathlessness at presentation, and Killip class III. After adjustment for differences in baseline and clinical characteristics, inpatient-onset STEMI was associated with significantly greater 1-year, 5-year, and 10-year all-cause mortality (1-year hazard ratio [HR], 1.27 [95% CI, 1.13-1.43]; 5-year HR, 1.27 [95% CI, 1.13-1.43]). There was no difference in 30-day all-cause or short-/long-term cardiovascular mortality. CONCLUSIONS: Inpatient-onset STEMI was linked to an increased long-term risk of all-cause mortality compared with outpatient-onset STEMI despite a shorter recognition-to-balloon time
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