Motile metal−organic frameworks (MOFs) are potential candidates to serve as small‐scale robotic platforms for applications in environmental remediation, targeted drug delivery, or nanosurgery. Here, ...magnetic helical microstructures coated with a kind of zinc‐based MOF, zeolitic imidazole framework‐8 (ZIF‐8), with biocompatibility characteristics and pH‐responsive features, are successfully fabricated. Moreover, it is shown that this highly integrated multifunctional device can swim along predesigned tracks under the control of weak rotational magnetic fields. The proposed systems can achieve single‐cell targeting in a cell culture media and a controlled delivery of cargo payloads inside a complex microfluidic channel network. This new approach toward the fabrication of integrated multifunctional systems will open new avenues in soft microrobotics beyond current applications.
A metal−organic‐framework‐based microrobot that can be precisely navigated by weak rotational magnetic fields is presented. This soft‐based microrobot is capable of performing single‐cell targeting in a cell culture media, as well as a controlled delivery of cargo payloads in a regioselective manner inside a complex microfluidic channel network.
Extreme environmental events are often catalysts for adaptive changes. Like many such events, the 2012 marine heatwave in the Gulf of Maine revealed unexpected connections within the ecosystem and ...between the natural and human components of the system. The strongest economic impacts were to Maine’s valuable lobster fishery. In 2012, early and intense landings led to a backlog in the supply chain and a drop in price. This experience prompted the lobster industry to implement changes throughout the supply chain to avoid the severe drop in price should another warm year with early landings occur. Here we describe a second heatwave in the Gulf of Maine that occurred in 2016. Despite a similar pattern in monthly landings, dockside prices for lobster were higher than expected. The contrast with 2012 suggests that the adaptations in the supply chain were successful. The 2012 and 2016 heatwaves are part of a broader pattern of temperature changes in this region. Warmer autumns allow sea turtles to remain in the Gulf of Maine longer, increasing their risk of being stunned or killed by cold water, and warm years followed by cold years typically lead to a decline in lobster landings. While there is evidence for adaptation to rising temperatures in the Gulf of Maine, the adaptation brought a significant shock to the system. Forecasts may help foster adaptation while avoiding shocks, but this will require a substantial shift in the mindsets of both forecast producers and consumers.
Worldwide, the number of patients able to benefit from kidney transplantation is greatly restricted by the severe shortage of deceased donor organs. Allocation of this scarce resource is increasingly ...challenging and complex. Striking an acceptable balance between efficient use of (utility) and fair access to (equity) the limited supply of donated kidneys raises controversial but important debates at ethical, medical, and social levels. There is no international consensus on the recipient and donor factors that should be considered in the kidney allocation process. There is a general trend toward a reduction in the influence of human leukocyte antigen mismatch and an increase in the importance of other factors shown to affect posttransplant outcomes, such as cold ischemia, duration of dialysis, donor and recipient age, and comorbidity. Increased consideration of equity has led to improved access to transplantation for disadvantaged patient groups. There has been an overall improvement in the transparency and accountability of allocation policies. Novel and contentious approaches in kidney allocation include the use of survival prediction scores as a criterion for accessing the waiting list and at the point of organ offering with matching of predicted graft and recipient survival. This review compares the diverse international approaches to deceased donor kidney allocation and their evolution over the last decade.
Adaptation to cold is one of the greatest challenges to forest trees. This process is highly synchronized with environmental cues relating to photoperiod and temperature. Here, we use a candidate ...gene-based approach to search for genetic associations between 384 single-nucleotide polymorphism (SNP) markers from 117 candidate genes and 21 cold-hardiness related traits. A general linear model approach, including population structure estimates as covariates, was implemented for each marker-trait pair. We discovered 30 highly significant genetic associations false discovery rate (FDR) Q < 0.10 across 12 candidate genes and 10 of the 21 traits. We also detected a set of 7 markers that had elevated levels of differentiation between sampling sites situated across the Cascade crest in northeastern Washington. Marker effects were small (r(2) < 0.05) and within the range of those published previously for forest trees. The derived SNP allele, as measured by a comparison to a recently diverged sister species, typically affected the phenotype in a way consistent with cold hardiness. The majority of markers were characterized as having largely nonadditive modes of gene action, especially underdominance in the case of cold-tolerance related phenotypes. We place these results in the context of trade-offs between the abilities to grow longer and to avoid fall cold damage, as well as putative epigenetic effects. These associations provide insight into the genetic components of complex traits in coastal Douglas fir, as well as highlight the need for landscape genetic approaches to the detection of adaptive genetic diversity.
Recurrence of adhesive small bowel obstruction (ASBO) can lead to multiple admissions. There is limited knowledge of the role of operative and nonoperative treatment in the long-term recurrence risk ...for ASBO. We sought to determine the effect of operative and nonoperative management on future ASBO recurrences.
This is a retrospective study of administrative discharge data from the Tennessee Hospital Association. Adult discharges from 2007 to 2009 with ASBO and all subsequent readmission within any hospital in the state were included; patients with earlier ASBO from 2003 to 2007 and out-of-state residents were excluded. ASBO recurrence was compared between operative and nonoperative approaches using the Andersen-Gill approach for modeling recurrent time-to-event data. Secondary outcomes included mortality, complication, and time to recurrence.
We analyzed 6,191 records; 30.0% were initially treated operatively. Patients initially managed surgically had lower overall recurrence rates (19.0% vs 25.6%; p < 0.005). The hazard for recurrence was lower if the most recent ASBO management was operative (hazard ratio 0.27; 95% CI, 0.23 to 0.31). The risk of ASBO recurrence increased with more cumulative operative or nonoperative ASBO admissions relative to patients with fewer earlier admissions (operative: hazard ratio 2.30; 95% CI, 2.04 to 2.60 and nonoperative: hazard ratio 1.18; 95% CI, 1.16 to 1.20). In-hospital mortality rate (3.7% vs 2.6%; p = 0.025) and time to recurrence (729 vs 550 days; p = 0.009) were greater in the operative group.
Operative management for the most recent ASBO is associated with fewer recurrences. Subsequent cumulative recurrences of ASBO predispose to recurrence regardless of operative or nonoperative management. When considering ASBO management, subsequent recurrence should be considered.
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Model-based calibration of a magnetic workspace not only provides a smooth representation of the field and its gradient matrix, but also uses physical constraints to smooth the calibration ...measurements. This paper presents the first model-based technique to calibrate a magnetic manipulation system by using nonlinear least squares to solve for a scalar potential for each source. The performance of the method is verified by comparison to numerical finite element simulation and a case study calibration of a real system, where it is able to achieve an R 2 value of 0.9997. Furthermore, the analytical representations for the first three spatial derivatives of a spherical multipole expansion are provided for convenience, which correspond to the torque, force, and force-spatial-rate-of-change on a magnetic dipole in the workspace.
Wide-field optical surveys have begun to uncover large samples of fast (trise <~ 5 d), luminous (Mpeak < −18), blue transients. While commonly attributed to the breakout of a supernova shock into a ...dense wind, the great distances to the transients of this class found so far have hampered detailed investigation of their properties. We present photometry and spectroscopy from a comprehensive worldwide campaign to observe AT 2018cow (ATLAS 18qqn), the first fast-luminous optical transient to be found in real time at low redshift. Our first spectra (<2 days after discovery) are entirely featureless. A very broad absorption feature suggestive of near relativistic velocities develops between 3 and 8 days, then disappears. Broad emission features of H and He develop after >10 days. The spectrum remains extremely hot throughout its evolution, and the photospheric radius contracts with time (receding below R < 1014 cm after 1 month). This behaviour does not match that of any known supernova, although a relativistic jet within a fallback supernova could explain some of the observed features. Alternatively, the transient could originate from the disruption of a star by an intermediate-mass black hole, although this would require long-lasting emission of highly super-Eddington thermal radiation. In either case, AT 2018cow suggests that the population of fast luminous transients represents a new class of astrophysical event. Intensive follow-up of this event in its late phases, and of any future events found at comparable distance, will be essential to better constrain their origins.
ABSTRACT We report a multiwavelength (X-ray, ultraviolet/optical/infrared (UVOIR), radio) analysis of the relativistic tidal disruption event (TDE) candidate Sw J2058+05 from 3 months to 3 yr ...post-discovery in order to study its properties and compare its behavior with that of Sw J1644+57. Our main results are as follows: (1) The long-term X-ray light curve of Sw J2058+05 shows a remarkably similar trend to that of Sw J1644+57. After a prolonged power-law decay, the X-ray flux drops off rapidly by a factor of 160 within a span of Δt/ . Associating this sudden decline with the transition from super-Eddington to sub-Eddington accretion, we estimate the black hole mass to be in the range of 104-6 M . (2) We detect rapid ( 500 s) X-ray variability before the drop-off, suggesting that, even at late times, the X-rays originate from close to the black hole (ruling out a forward-shock origin). (3) We confirm using Hubble Space Telescope and Very Long Baseline Array astrometry that the location of the source coincides with the galaxy's center to within 400 pc (in projection). (4) We modeled Sw J2058+05's UVOIR spectral energy distribution with a single-temperature blackbody and find that while the radius remains more or less constant at a value of 63.4 4.5 AU ( cm) at all times during the outburst, the blackbody temperature drops significantly from ∼30,000 K at early times to a value of ∼15,000 K at late times (before the X-ray drop-off). Our results strengthen Sw J2058+05's interpretation as a TDE similar to Sw J1644+57.
Ischemia-reperfusion (IR) injury to the kidney occurs in a range of clinically important scenarios including hypotension, sepsis and in surgical procedures such as cardiac bypass surgery and kidney ...transplantation, leading to acute kidney injury (AKI). Mitochondrial oxidative damage is a significant contributor to the early phases of IR injury and may initiate a damaging inflammatory response. Here we assessed whether the mitochondria targeted antioxidant MitoQ could decrease oxidative damage during IR injury and thereby protect kidney function. To do this we exposed kidneys in mice to in vivo ischemia by bilaterally occluding the renal vessels followed by reperfusion for up to 24h. This caused renal dysfunction, measured by decreased creatinine clearance, and increased markers of oxidative damage. Administering MitoQ to the mice intravenously 15 min prior to ischemia protected the kidney from damage and dysfunction. These data indicate that mitochondrial oxidative damage contributes to kidney IR injury and that mitochondria targeted antioxidants such as MitoQ are potential therapies for renal dysfunction due to IR injury.
Current genetic data are equivocal as to whether goat domestication occurred multiple times or was a singular process. We generated genomic data from 83 ancient goats (51 with genome-wide coverage) ...from Paleolithic to Medieval contexts throughout the Near East. Our findings demonstrate that multiple divergent ancient wild goat sources were domesticated in a dispersed process that resulted in genetically and geographically distinct Neolithic goat populations, echoing contemporaneous human divergence across the region. These early goat populations contributed differently to modern goats in Asia, Africa, and Europe. We also detect early selection for pigmentation, stature, reproduction, milking, and response to dietary change, providing 8000-year-old evidence for human agency in molding genome variation within a partner species.
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