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Advanced unsaturated soil mechanics and engineering
Analytical and comprehensive, this work examines the mechanics and engineering of unsaturated soils, as well as explaining the laboratory and field testing, and research that are the logical basis of this modern approach to safe construction in these hazardous geomaterials.
Book
A real-world comparison of outcomes between fractional flow reserve-guided versus angiography-guided percutaneous coronary intervention
Fractional flow reserve (FFR)-guided percutaneous coronary intervention (PCI) has been shown to be superior to angiography-guided PCI in randomized controlled studies. However, real-world data on the use and outcomes of FFR-guided PCI remain limited. Thus, we investigated the outcomes of patients undergoing FFR-guided PCI compared to angiography-guided PCI in a large, state-wide unselected cohort.
All patients undergoing PCI between June 2017 and June 2018 in New South Wales, Australia, were included. The cohort was stratified into the FFR-guided group when concomitant FFR was performed, and the angiography-guided group when no FFR was performed. The primary outcome was a combined endpoint of death or myocardial infarction (MI). Secondary outcomes included all-cause death, cardiovascular (CVS) death, and MI. The cohort comprised 10,304 patients, of which 542 (5%) underwent FFR-guided PCI. During a mean follow-up of 12±4 months, the FFR-guided PCI group had reduced occurrence of the primary outcome (hazard ratio [HR] 0.34, 95% confidence intervals [CI] 0.20-0.56, P<0.001), all-cause death (HR 0.18, 95% CI 0.07-0.47, P = 0.001), CVS death (HR 0.21, 95% CI 0.07-0.66, P = 0.01), and MI (HR 0.46, 95% CI 0.25-0.84, P = 0.01) compared to the angiography-guided PCI group. Multivariable Cox regression analysis showed FFR-guidance to be an independent predictor of the primary outcome (HR 0.45, 95% CI 0.27-0.75, P = 0.002), all-cause death (HR 0.22, 95% CI 0.08-0.59, P = 0.003), and CVS death (HR 0.27, 95% CI 0.09-0.83, P = 0.02).
In this real-world study of patients undergoing PCI, FFR-guidance was associated with lower rates of the primary outcome of death or MI, as well as the secondary outcomes of all-cause death and CVS death.
Journal Article
Diabesity: the combined burden of obesity and diabetes on heart disease and the role of imaging
Diabesity is a term used to describe the combined adverse health effects of obesity and diabetes mellitus. The worldwide dual epidemic of obesity and type 2 diabetes is an important public health issue. Projections estimate a sixfold increase in the number of adults with obesity in 40 years and an increase in the number of individuals with diabetes to 642 million by 2040. Increased adiposity is the strongest risk factor for developing diabetes. Early detection of the effects of diabesity on the cardiovascular system would enable the optimal implementation of effective therapies that prevent atherosclerosis progression, cardiac remodelling, and the resulting ischaemic heart disease and heart failure. Beyond conventional imaging techniques, such as echocardiography, CT and cardiac magnetic resonance, novel post-processing tools and techniques provide information on the biological processes that underlie metabolic heart disease. In this Review, we summarize the effects of obesity and diabetes on myocardial structure and function and illustrate the use of state-of-the-art multimodality cardiac imaging to elucidate the pathophysiology of myocardial dysfunction, prognosticate long-term clinical outcomes and potentially guide treatment strategies.In this Review, Bax and colleagues summarize the effects of obesity and diabetes on myocardial structure and function and evaluate the role of multimodality cardiac imaging to elucidate the pathophysiology of myocardial dysfunction, prognosticate long-term clinical outcomes and potentially guide treatment strategies.
Journal Article
Mechanism of action of a WWTR1(TAZ)-CAMTA1 fusion oncoprotein
The WWTR1 (protein is known as TAZ)
-CAMTA1
(
WC
) fusion gene defines epithelioid hemangioendothelioma, a malignant vascular cancer. TAZ (
t
ranscriptional co
a
ctivator with PD
Z
binding motif) is a transcriptional coactivator and end effector of the Hippo tumor suppressor pathway. It is inhibited by phosphorylation by the Hippo kinases LATS1 and LATS2. Such phosphorylation causes cytoplasmic localization, 14-3-3 protein binding and the phorphorylation of a terminal phosphodegron promotes ubiquitin-dependent degradation (the phosphorylation of the different motifs has several effects). CAMTA1 is a putative tumor suppressive transcription factor. Here we demonstrate that TAZ-CAMTA1 (TC) fusion results in its nuclear localization and constitutive activation. Consequently, cells expressing TC display a TAZ-like transcriptional program that causes resistance to anoikis and oncogenic transformation. Our findings elucidate the mechanistic basis of TC oncogenic properties, highlight that TC is an important model to understand how the Hippo pathway can be inhibited in cancer, and provide approaches for targeting this chimeric protein.
Journal Article
Evidence on physical activity and falls prevention for people aged 65+ years: systematic review to inform the WHO guidelines on physical activity and sedentary behaviour
Background
Exercise prevents falls in older adults. Regular updates of estimated effects of exercise on falls are warranted given the number of new trials, the increasing number of older people globally and the major consequences of falls and fall-related injuries.
Methods
This update of a 2019 Cochrane Review was undertaken to inform the World Health Organization guidelines on physical activity and sedentary behaviour. Searches were conducted in six databases. We included randomised controlled trials evaluating effects of any form of physical activity as a single intervention on falls in people aged 60+ years living in the community. Analyses explored dose-response relationships. The certainty of the evidence was assessed using Grading of Recommendations Assessment, Development and Evaluation (GRADE).
Results
This review included 116 studies, involving 25,160 participants; nine new studies since the 2019 Cochrane Review. Exercise reduces the rate of falls by 23% (pooled rate ratio (RaR) 0.77, 95% confidence interval (CI) 0.71 to 0.83, 64 studies, high certainty evidence). Subgroup analysis showed variation in effects of different types of exercise (
p
< 0.01). Rate of falls compared with control is reduced by 24% from balance and functional exercises (RaR 0.76, 95% CI 0.70 to 0.82, 39 studies, high certainty evidence), 28% from programs involving multiple types of exercise (commonly balance and functional exercises plus resistance exercises, RaR 0.72, 95% CI 0.56 to 0.93, 15 studies, moderate certainty evidence) and 23% from Tai Chi (RaR 0.77, 95% CI 0.61 to 0.97, 9 studies, moderate certainty evidence). The effects of programs that primarily involve resistance training, dance or walking remain uncertain. Interventions with a total weekly dose of 3+ h that included balance and functional exercises were particularly effective with a 42% reduction in rate of falls compared to control (Incidence Rate Ratio (IRR) 0.58, 95% CI 0.45 to 0.76). Subgroup analyses showed no evidence of a difference in the effect on falls on the basis of participant age over 75 years, risk of falls as a trial inclusion criterion, individual versus group exercise, or whether a health professional delivered the intervention.
Conclusions
Given the strength of this evidence, effective exercise programs should now be implemented at scale.
Journal Article
Structural color three-dimensional printing by shrinking photonic crystals
The coloration of some butterflies, Pachyrhynchus weevils, and many chameleons are notable examples of natural organisms employing photonic crystals to produce colorful patterns. Despite advances in nanotechnology, we still lack the ability to print arbitrary colors and shapes in all three dimensions at this microscopic length scale. Here, we introduce a heat-shrinking method to produce 3D-printed photonic crystals with a 5x reduction in lattice constants, achieving sub-100-nm features with a full range of colors. With these lattice structures as 3D color volumetric elements, we printed 3D microscopic scale objects, including the first multi-color microscopic model of the Eiffel Tower measuring only 39 µm tall with a color pixel size of 1.45 µm. The technology to print 3D structures in color at the microscopic scale promises the direct patterning and integration of spectrally selective devices, such as photonic crystal-based color filters, onto free-form optical elements and curved surfaces.
The ability to print arbitrary colors and shapes in all three dimensions at microscopic length scales is still lacking. Here, the authors introduce a means to produce three-dimensionally-printed photonic crystals with a periodicity as small as 280 nm, achieving sub-100-nm features with a full range of colors.
Journal Article
Measurement of non-monotonic Casimir forces between silicon nanostructures
Previous demonstrations of the elusive Casimir force between interfaces exhibit monotonic dependence on surface displacement. Now a non-monotonic dependence of the force has been shown experimentally by exploting nanostructured surfaces.
Casimir forces are of fundamental interest because they originate from quantum fluctuations of the electromagnetic field
1
. Apart from controlling this force via the optical properties of materials
2
,
3
,
4
,
5
,
6
,
7
,
8
,
9
,
10
,
11
, a number of novel geometries have been proposed to generate repulsive and/or non-monotonic Casimir forces between bodies separated by vacuum gaps
12
,
13
,
14
. Experimental realization of these geometries, however, is hindered by the difficulties in alignment when the bodies are brought into close proximity. Here, using an on-chip platform with integrated force sensors and actuators
15
, we circumvent the alignment problem and measure the Casimir force between two surfaces with nanoscale protrusions. We demonstrate that the force depends non-monotonically on the displacement. At some displacements, the Casimir force leads to an effective stiffening of the nanomechanical spring. Our findings pave the way for exploiting the Casimir force in nanomechanical systems using structures of complex and non-conventional shapes.
Journal Article
A repeating fast radio burst source localized to a nearby spiral galaxy
Fast radio bursts (FRBs) are brief, bright, extragalactic radio flashes (1,2). Their physical origin remains unknown, but dozens of possible models have been postulated³. Some FRB sources exhibit repeat bursts⁴⁻⁷. Although over a hundred FRB sources have been discovered⁸, only four have been localized and associated with a host galaxy⁹⁻¹², and just one of these four is known to emit repeating FRBs⁹. The properties of the host galaxies, and the local environments of FRBs, could provide important clues about their physical origins. The first known repeating FRB, however, was localized to a low-metallicity, irregular dwarf galaxy, and the apparently non-repeating sources were localized to higher-metallicity, massive elliptical or star-forming galaxies, suggesting that perhaps the repeating and apparently non-repeating sources could have distinct physical origins. Here we report the precise localization of a second repeating FRB source⁶, FRB 180916.J0158+65, to a star-forming region in a nearby (redshift 0.0337 ± 0.0002) massive spiral galaxy, whose properties and proximity distinguish it from all known hosts. The lack of both a comparably luminous persistent radio counterpart and a high Faraday rotation measure⁶ further distinguish the local environment of FRB 180916.J0158+65 from that of the single previously localized repeating FRB source, FRB 121102. This suggests that repeating FRBs may have a wide range of luminosities, and originate from diverse host galaxies and local environments.
Journal Article
A repeating fast radio burst source in a globular cluster
Fast radio bursts (FRBs) are flashes of unknown physical origin
1
. The majority of FRBs have been seen only once, although some are known to generate multiple flashes
2
,
3
. Many models invoke magnetically powered neutron stars (magnetars) as the source of the emission
4
,
5
. Recently, the discovery
6
of another repeater (FRB 20200120E) was announced, in the direction of the nearby galaxy M81, with four potential counterparts at other wavelengths
6
. Here we report observations that localized the FRB to a globular cluster associated with M81, where it is 2 parsecs away from the optical centre of the cluster. Globular clusters host old stellar populations, challenging FRB models that invoke young magnetars formed in a core-collapse supernova. We propose instead that FRB 20200120E originates from a highly magnetized neutron star formed either through the accretion-induced collapse of a white dwarf, or the merger of compact stars in a binary system
7
. Compact binaries are efficiently formed inside globular clusters, so a model invoking them could also be responsible for the observed bursts.
The fast radio burst FRB 20200120E is shown to originate from a globular cluster in the galaxy M81, and may be a collapsed white dwarf or a merged compact binary star system.
Journal Article
Relativistic Shapiro Delay Measurements of an Extremely Massive Millisecond Pulsar
Despite its importance to our understanding of physics at supranuclear densities, the equation of state (EoS) of matter deep within neutron stars remains poorly understood. Millisecond pulsars (MSPs) are among the most useful astrophysical objects in the Universe for testing fundamental physics, and place some of the most stringent constraints on this high-density EoS. Pulsar timing—the process of accounting
for every rotation of a pulsar over long time periods—can precisely measure a wide variety of physical phenomena, including those that allow the measurement of the masses of the components of a pulsar binary system1. One of these, called relativistic Shapiro delay2, can yield precise masses for both an MSP and its companion; however, it is only easily observed in a small subset of high-precision, highly inclined (nearly edge-on) binary pulsar systems. By combining data from the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) 12.5-yr data set with recent orbitalphase- specific observations using the Green Bank Telescope, we have measured the mass of the MSP J0740+6620 to be 2.14+0:10-0:09 M⊙ (68.3% credibility interval; the 95.4% credibility interval is 2.14+0:20-0:18 M⊙). It is highly likely to be the most massive neutron star yet observed, and serves as a strong constraint on the neutron star interior EoS.
Journal Article