Quantum algorithms offer a dramatic speedup for computational problems in material science and chemistry. However, any near-term realizations of these algorithms will need to be optimized to fit ...within the finite resources offered by existing noisy hardware. Here, taking advantage of the adjustable coupling of gmon qubits, we demonstrate a continuous two-qubit gate set that can provide a threefold reduction in circuit depth as compared to a standard decomposition. We implement two gate families: an imaginary swap-like (iSWAP-like) gate to attain an arbitrary swap angle, θ, and a controlled-phase gate that generates an arbitrary conditional phase, ϕ. Using one of each of these gates, we can perform an arbitrary two-qubit gate within the excitation-preserving subspace allowing for a complete implementation of the so-called Fermionic simulation (fSim) gate set. We benchmark the fidelity of the iSWAP-like and controlled-phase gate families as well as 525 other fSim gates spread evenly across the entire fSim (θ, ϕ) parameter space, achieving a purity-limited average two-qubit Pauli error of 3.8 × 10−3 per fSim gate.
Hillslope‐scale rainfall‐runoff processes leading to a fast catchment response are not explicitly included in land surface models (LSMs) for use in earth system models (ESMs) due to computational ...constraints. This study presents a hybrid‐3D hillslope hydrological model (h3D) that couples a 1‐D vertical soil column model with a lateral pseudo‐2D saturated zone and overland flow model for use in ESMs. By representing vertical and lateral responses separately at different spatial resolutions, h3D is computationally efficient. The h3D model was first tested for three different hillslope planforms (uniform, convergent and divergent). We then compared h3D (with single and multiple soil columns) with a complex physically based 3‐D model and a simple 1‐D soil moisture model coupled with an unconfined aquifer (as typically used in LSMs). It is found that simulations obtained by the simple 1‐D model vary considerably from the complex 3‐D model and are not able to represent hillslope‐scale variations in the lateral flow response. In contrast, the single soil column h3D model shows a much better performance and saves computational time by 2‐3 orders of magnitude compared with the complex 3‐D model. When multiple vertical soil columns are implemented, the resulting hydrological responses (soil moisture, water table depth, and base flow along the hillslope) from h3D are nearly identical to those predicted by the complex 3‐D model, but still saves computational time. As such, the computational efficiency of the h3D model provides a valuable and promising approach to incorporating hillslope‐scale hydrological processes into continental and global‐scale ESMs.
Key Points:
This study presents a hybrid‐3D model for the hillslope hydrological response
Hydrological simulations are similar to those predicted by a 3‐D Richards model
The hybrid‐3D model is computationally 2‐3 orders of magnitude more efficient
Context.
Jeans escape is believed to dominate atmospheric escape for most outer Solar System bodies. However, non-thermal mechanisms, particularly atmospheric and ionospheric chemistry, are likely to ...contribute substantially to neutral escape on Triton.
Aims.
This study is devoted to evaluating the role of the chemically induced escape of H, H
2
, C, N, O, N
2
, and CO on Triton via a variety of processes. Here, we also aim to identify the dominant processes for these species.
Methods.
We used the background atmospheric and ionospheric structures from available model calculations. We constructed a test particle Monte Carlo model to determine the escape probability profiles of various species released from 35 channels. Species-dependent and energy-dependent cross sections were adopted in our calculations, along with a strongly forward-scattering angle distribution, all constrained by the available laboratory measurements.
Results.
The chemical escape rates on Triton are derived as 4.5 × 10
24
s
−1
for total H, 6.9 × 10
22
s
−1
for total C, 8.0 × 10
24
s
−1
for total N, and 1.4 × 10
23
s
−1
for total O.
Conclusions.
Based on a comparison with the respective Jeans escape rates, our calculations indicate that atmospheric and ionospheric chemistry make small but non-negligible contributions to both H and C escape on Triton, whereas its contributions to N and O escape are significant.
Introduction: Sclerosteosis is a rare high bone mass genetic disorder in humans caused by inactivating mutations in SOST, the gene encoding sclerostin. Based on these data, sclerostin has emerged as ...a key negative regulator of bone mass. We generated SOST knockout (KO) mice to gain a more detailed understanding of the effects of sclerostin deficiency on bone.
Materials and Methods: Gene targeting was used to inactivate SOST and generate a line of SOST KO mice. Radiography, densitometry, μCT, histomorphometry, and mechanical testing were used to characterize the impact of sclerostin deficiency on bone in male and female mice. Comparisons were made between same sex KO and wildtype (WT) mice.
Results: The results for male and female SOST KO mice were similar, with differences only in the magnitude of some effects. SOST KO mice had increased radiodensity throughout the skeleton, with general skeletal morphology being normal in appearance. DXA analysis of lumbar vertebrae and whole leg showed that there was a significant increase in BMD (>50%) at both sites. μCT analysis of femur showed that bone volume was significantly increased in both the trabecular and cortical compartments. Histomorphometry of trabecular bone revealed a significant increase in osteoblast surface and no significant change in osteoclast surface in SOST KO mice. The bone formation rate in SOST KO mice was significantly increased for trabecular bone (>9‐fold) at the distal femur, as well as for the endocortical and periosteal surfaces of the femur midshaft. Mechanical testing of lumbar vertebrae and femur showed that bone strength was significantly increased at both sites in SOST KO mice.
Conclusions: SOST KO mice have a high bone mass phenotype characterized by marked increases in BMD, bone volume, bone formation, and bone strength. These results show that sclerostin is a key negative regulator of a powerful, evolutionarily conserved bone formation pathway that acts on both trabecular and cortical bone.
Recently, a new two-dimensional material, single- or few-layered black phosphorus (BP), has attracted considerable attention for applications in electronics, optoelectronics, and batteries due to its ...unique properties, including large specific surface area, anisotropy, and tunable and direct band gaps. In particular, contributions to electrochemical energy storage devices, such as lithium and sodium ion batteries and supercapacitors, have emerged. However, critical issues remain to be explored before scaled-up commercial production of BP, such as preparation, stability, and performance. Herein, we present the first review of recent progress in BP-based electrochemical energy storage device. The preparation and electrochemical properties of black phosphorus, recent advances, potential challenges, and relevant perspectives in electrochemical energy storage, and the potential of BP are discussed in this work.
Recently, a new two-dimensional material, single- or few-layered black phosphorus (BP), has attracted considerable attention for applications in electrochemical energy storage, due to its ultrahigh theoretical capacity, and can hopefully become commercialized in the near future.
Abstract
In the absence of solar radiation, precipitating electrons from the solar wind (SW) are generally thought to be the dominant source of energy deposition in the nightside Martian upper ...atmosphere, creating a patchy ionosphere and possibly also affecting the nightside thermal budget of various neutral and ionized species. Previous model calculations have not taken into account in situ heating via SW electron impact. In the present study, we utilize extensive measurements made by several instruments on board the Mars Atmosphere and Volatile Evolution spacecraft, in order to perform data-driven computations of the nightside neutral, ion, and electron heating rates. Considering the large range of energetic electron intensity observed on the nightside of Mars, we divide the entire data set into two subsamples, either with or without energetic electron depletion, a notable feature of the nightside Martian ionosphere. Our calculations indicate that in situ nightside neutral heating is dominated by exothermic chemistry and Maxwell interaction with thermal ions for regions with depletion, and by direct SW impact for regions without. Collisional quenching of excited state species produced from a variety of channels, such as electron impact excitation, dissociation, and ionization, as well as
dissociative recombination, makes a substantial contribution to neutral heating, except during depletion. For comparison, nightside ion heating is mainly driven by energetic ion production under all circumstances, which occurs mainly via ion-neutral reaction O
+
+ CO
2
and CO
2
+
predissociation.
Objective:To examine the relationship between longitudinal fluctuations in synovitis with change in pain and cartilage in knee osteoarthritis.Methods:Study subjects were patients 45 years of age and ...older with symptomatic knee osteoarthritis from the Boston Osteoarthritis of the Knee Study. Baseline and follow-up assessments at 15 and 30 months included knee magnetic resonance imaging (MRI), BMI and pain assessment (VAS) over the last week. Synovitis was scored at 3 locations (infrapatellar fat pad, suprapatellar and intercondylar regions) using a semiquantitative scale (0–3) at all 3 time points on MRI. Scores at each site were added to give a summary synovitis score (0–9).Results:We assessed 270 subjects whose mean (SD) age was 66.7 (9.2) years, BMI 31.5 (5.7) kg/m2; 42% were female. There was no correlation of baseline synovitis with baseline pain score (r = 0.09, p = 0.17). The change in summary synovitis score was correlated with the change in pain (r = 0.21, p = 0.0003). An increase of one unit in summary synovitis score resulted in a 3.15-mm increase in VAS pain score (0–100 scale). Effusion change was not associated with pain change. Of the 3 locations for synovitis, changes in the infrapatellar fat pad were most strongly related to pain change. Despite cartilage loss occurring in over 50% of knees, synovitis was not associated with cartilage loss in either tibiofemoral or patellofemoral compartment.Conclusions:Change in synovitis was correlated with change in knee pain, but not loss of cartilage. Treatment of pain in knee osteoarthritis (OA) needs to consider treatment of synovitis.
The β-decay half-lives of neutron-rich nuclei with 20≤Z≤50 are systematically investigated using the newly developed fully self-consistent proton–neutron quasiparticle random phase approximation ...(QRPA), based on the spherical relativistic Hartree–Fock–Bogoliubov (RHFB) framework. Available data are reproduced by including an isospin-dependent proton–neutron pairing interaction in the isoscalar channel of the RHFB+QRPA model. With the calculated β-decay half-lives of neutron-rich nuclei a remarkable speeding up of r-matter flow is predicted. This leads to enhanced r-process abundances of elements with A≳140, an important result for the understanding of the origin of heavy elements in the universe.
Aim
To gain deeper insights into the clostridial community dynamics and chemical transformations during the ensiling of alfalfa.
Methods and Results
Direct‐cut alfalfa silage (with the dry matter ...content of 240 g kg−1) was prepared with or without the addition of a lactic acid bacterial inoculant and sucrose. Silages were sampled at 0, 3, 7, 14, 28 and 56 days after ensiling and their bacterial community was determined using high‐throughput sequencing with a special focus on the clostridial community. A clostridial fermentation occurred in the control silage, with high contents of acetic acid, butyric acid and ammonia nitrogen and Clostridia counts; while the inoculated silage was well preserved, with low pH and high lactic acid content. Lactic acid bacteria dominated the bacterial community during the ensiling process. In the control silage, Weissella confusa, Lactobacillus brevis, Enterococcus mundtii and Pediococcus acidilactici were identified at the beginning of the fermentation. Thereafter, W. confusa, Lactobacillus helsingborgensis and Bifidobacterium asteroides appeared and quickly prevailed. In the inoculated silage, Lactobacillus plantarum dominated the whole ensiling process. The genus Clostridium dominated the clostridial community, and was depressed with the inoculated treatment. Clostridium perfringens, Garciella sp. and Clostridium baratii were the main initiators of the clostridial fermentation of the control silage, while Clostridium tyrobutyricum became the most abundant Clostridia with prolonged ensiling. Overall in the inoculated silage, little changes in the clostridial community were observed throughout the ensiling period. Treating alfalfa silage with a homolactic acid‐based bacterial inoculant prevented a clostridial fermentation resulting in more efficient fermentation.
Conclusion
Distinct changes in the bacterial community with a special focus on the clostridial community were associated with the development of the clostridial fermentation during the ensiling of alfalfa.
Significance and Impact of the Study
High‐throughput sequencing based on a novel Clostridia‐specific primer set proved a potentially useful tool to study the clostridial community dynamics, and could aid to elucidate the mechanism by which the clostridial fermentation develops during the ensiling of alfalfa.
Abstract Objective Multi-mode universal adhesives offer clinicians the choice of using the etch-and-rinse technique, selective enamel etch technique or self-etch technique to bond to tooth ...substrates. The present study examined the short-term in vitro performance of five universal adhesives bonded to human coronal dentine. Methods Two hundred non-carious human third molars were assigned to five groups based on the type of the universal adhesives (Prime&Bond Elect, Scotchbond Universal, All-Bond Universal, Clearfil Universal Bond and Futurabond U). Two bonding modes (etch-and-rinse and self-etch) were employed for each adhesive group. Bonded specimens were stored in deionized water for 24 h or underwent a 10,000-cycle thermocycling ageing process prior to testing ( N = 10). Microtensile bond testing (μTBS), transmission electron microscopy (TEM) of resin–dentine interfaces in non-thermocycled specimens and scanning electron microscopy (SEM) of tracer-infused water-rich zones within hybrid layers of thermocycled specimens were performed. Results Both adhesive type and testing condition (with/without thermocycling) have significant influences on μTBS. The use of each adhesive in either the etch-and-rinse or self-etch application mode did not result in significantly different μTBS to dentine. Hybrid layers created by these adhesives in the etch-and-rinse bonding mode and self-etch bonding mode were ∼5 μm and ≤0.5 μm thick respectively. Tracer-infused regions could be identified within the resin–dentine interface from all the specimens prepared. Conclusion The increase in versatility of universal adhesives is not accompanied by technological advances for overcoming the challenges associated with previous generations of adhesives. Therapeutic adhesives with bio-protective and bio-promoting effects are still lacking in commercialized adhesives. Clinical significance Universal adhesives represent manufacturers’ attempt to introduce versatility in product design via adaptation of a single-bottle self-etch adhesive for other application modes without compromising its bonding effectiveness.
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