Soil acidification is a major problem in soils of intensive Chinese agricultural systems. We used two nationwide surveys, paired comparisons in numerous individual sites, and several long-term ...monitoring-field data sets to evaluate changes in soil acidity. Soil pH declined significantly (P < 0.001) from the 1980s to the 2000s in the major Chinese crop-production areas. Processes related to nitrogen cycling released 20 to 221 kilomoles of hydrogen ion (H⁺) per hectare per year, and base cations uptake contributed a further 15 to 20 kilomoles of H⁺ per hectare per year to soil acidification in four widespread cropping systems. In comparison, acid deposition (0.4 to 2.0 kilomoles of H⁺ per hectare per year) made a small contribution to the acidification of agricultural soils across China.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
The material class of rare earth nickelates with high Ni3+ oxidation state is generating continued interest due to the occurrence of a metal-insulator transition with charge order and the appearance ...of non-collinear magnetic phases within this insulating regime. The recent theoretical prediction for superconductivity in LaNiO3 thin films has also triggered intensive research efforts. LaNiO3 seems to be the only rare earth nickelate that stays metallic and paramagnetic down to lowest temperatures. So far, centimeter-sized impurity-free single crystal growth has not been reported for the rare earth nickelates material class since elevated oxygen pressures are required for their synthesis. Here, we report on the successful growth of centimeter-sized LaNiO3 single crystals by the floating zone technique at oxygen pressures of up to 150 bar. Our crystals are essentially free from Ni2+ impurities and exhibit metallic properties together with an unexpected but clear antiferromagnetic transition.
We present ground-based and Swift photometric and spectroscopic observations of the candidate tidal disruption event (TDE) ASASSN-14li, found at the centre of PGC 043234 (d ... 90 Mpc) by the All-Sky ...Automated Survey for SuperNovae (ASAS-SN). The source had a peak bolometric luminosity of ... and a total integrated energy of ... erg radiated over the ~6 months of observations presented. The UV/optical emission of the source is well fitted by a blackbody with roughly constant temperature of T ... 35,000 K, while the luminosity declines by roughly a factor of 16 over this time. The optical/UV luminosity decline is broadly consistent with an exponential decline, ..., with t0 ... 60 d. ASASSN-14li also exhibits soft X-ray emission comparable in luminosity to the optical and UV emission but declining at a slower rate, and the X-ray emission now dominates. Spectra of the source show broad Balmer and helium lines in emission as well as strong blue continuum emission at all epochs. We use the discoveries of ASASSN-14li and ASASSN-14ae to estimate the TDE rate implied by ASAS-SN, finding an average rate of ... per galaxy with a 90 per cent confidence interval of ... per galaxy. ASAS-SN found roughly 1 TDE for every 70 Type Ia supernovae in 2014, a rate that is much higher than that of other surveys. (ProQuest: ... denotes formulae/symbols omitted.)
Creating oxide interfaces with precise chemical specificity at the atomic layer level is desired for the engineering of quantum phases and electronic applications, but highly challenging, owing ...partially to the lack of in situ tools to monitor the chemical composition and completeness of the surface layer during growth. Here we report the in situ observation of atomic layer-by-layer inner potential variations by analysing the Kikuchi lines during epitaxial growth of strontium titanate, providing a powerful real-time technique to monitor and control the chemical composition during growth. A model combining the effects of mean inner potential and step edge density (roughness) reveals the underlying mechanism of the complex and previously not well-understood reflection high-energy electron diffraction oscillations observed in the shuttered growth of oxide films. General rules are proposed to guide the synthesis of atomically and chemically sharp oxide interfaces, opening up vast opportunities for the exploration of intriguing quantum phenomena at oxide interfaces.
Global manufacturing companies have some pressing needs to improve production visibility and decision-making performance by implementing effective production monitoring and scheduling. This paper ...proposes a radio frequency identification (RFID)-based intelligent decision support system architecture to handle production monitoring and scheduling in a distributed manufacturing environment. A pilot implementation of the architecture is reported in a distributed clothing manufacturing environment. RFID and cloud technologies were integrated for real-time and remote production capture and monitoring. Intelligent optimization techniques were also implemented to generate effective production scheduling solutions. A prototype system with remote monitoring and production scheduling functions was developed and implemented in a distributed manufacturing environment, which demonstrated the effectiveness of the architecture. The proposed architecture has good extensibility and scalability, which can easily be integrated with production decision-making as well as production and logistics operations in the supply chain. Lastly, this paper discusses the difficulties encountered and lessons learned during system implementation and the managerial implications of the proposed architecture.
•Integrate RFID, cloud technology and intelligent techniques for monitoring and scheduling.•RFID and cloud-based architecture improves production transparency and visibility.•Intelligent optimization techniques generate effective production scheduling solutions.•The architecture is helpful to increase production efficiency, and reduce wastes and costs.•Difficulties and lessons in implementation and managerial implications are discussed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
A theoretical and experimental perspective on the role of titanium impurities in hematite (α-Fe
2
O
3
) nanostructured photoelectrodes for solar fuel synthesis devices is provided. Titanium ...incorporation is a known correlate to efficiency enhancement in α-Fe
2
O
3
photoanodes for solar water oxidation; here the relevant literature and the latest advances are presented and various proposed mechanisms for enhancement are contrasted. Available experimental evidence suggests that Ti incorporation increases net electron carrier concentrations in electrodes, most likely to the extent that (synthesis-dependent) charge compensating cation vacancies are not present. However, electron conductivity increases alone cannot quantitatively account for the large associated photoelectrochemical performance enhancements. The magnitudes of the effects of Ti incorporation on electronic and magnetic properties appear to be highly synthesis-dependent, which has made difficult the development of consistent and general mechanisms explaining experimental and theoretical observations. In this context, we consider how the electronic structure correlates with Ti impurity incorporation in α-Fe
2
O
3
from the perspective of synchrotron-based soft X-ray absorption spectroscopy measurements. Measurements are performed on sets of electrodes fabricated by five relevant and unrelated chemical and physical techniques. The effects of titanium impurities are reflected in the electronic structure through several universally observed spectral characteristics, irrespective of the synthesis techniques. Absorption spectra at the oxygen K-edge show that Ti incorporation is associated with new oxygen 2p-hybridized states, overlapping with and distorting the known unoccupied Fe 3d-O 2p band of α-Fe
2
O
3
. This is an indication of mixing of Ti s and d states in the conduction band of α-Fe
2
O
3
. A comparison of spectra obtained with electron and photon detection shows that the effects of Ti incorporation on the conduction band are more pronounced in the near-surface region. Titanium L
2,3
-edge absorption spectra show that titanium is incorporated into α-Fe
2
O
3
as Ti
4+
by all fabrication methods, with no long-range titania order detected. Iron L
2,3
-edge absorption spectra indicate that Ti incorporation is not associated with the formation of any significant concentrations of Fe
2+
, an observation common to many prior studies on this material system.
A thorough literature review and the investigation by soft X-ray absorption spectroscopy at synchrotron facilities of Ti-Hematite photoelectrodes are provided.
Spin Hall effect (SHE) is studied with first-principles relativistic band calculations for platinum, which is one of the most important materials for metallic SHE and spintronics. We find that ...intrinsic spin Hall conductivity (SHC) is as large as approximately 2000(variant Planck's over 2 pi/e)(Omega cm)(-1) at low temperature and decreases down to approximately 200(variant Planck's over 2 pi/e)(Omega cm)(-1) at room temperature. It is due to the resonant contribution from the spin-orbit splitting of the doubly degenerated d bands at high-symmetry L and X points near the Fermi level. By modeling these near degeneracies by an effective Hamiltonian, we show that SHC has a peak near the Fermi energy and that the vertex correction due to impurity scattering vanishes. We therefore argue that the large SHE observed experimentally in platinum is of intrinsic nature.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
Microbiota and Food Allergy Shu, Shang-An; Yuen, Agatha W. T.; Woo, Elena ...
Clinical reviews in allergy & immunology,
08/2019, Volume:
57, Issue:
1
Journal Article
Peer reviewed
Emerging evidence suggests that the increasing prevalence of food allergies is associated with compositional and functional changes in our gut microbiota. Microbiota-host interactions play a key role ...in regulating the immune system. Development of a healthy gut microbiota and immune system occurs early in life and is largely shaped by exposure to maternal microbes through vaginal/natural delivery and breast milk, whereas use of antibiotics can disrupt gut homeostasis and significantly raise the risk of allergic diseases. Thus, changes in the quantity or diversity of gut microbes affect oral toleranace through interations of microbial molecules with pattern recognition receptors on immune cells and confer susceptibility to food allergies. On the other hand, short chain fatty acids which are fermentation end products of insoluble fibers by intestinal micoorganisms have been shown to confer protective effects on food allergy. As a preventive and therapeutic treatment for food allergies, probiotics have gained widespread attention in recent years. Reintroducing certain commensal microbes, such as Clostridia, both in animal models and clinical trials led to the prevention or resolution of allergic symptoms. This review highlights recent progress in our understanding of the gut microbiota’s role in food allergy. However, mechanistic details underlying the anti-allergic effects of probiotics and the interaction between the gut microbiota and the immune system remain circumstantial and are not fully understood. Future studies should address possible factors and underlying mechanisms for microbiota-host interactions and gut immunity, as well as the efficacy, safety, and appropriate use of probiotics in establishing a standard treatment regimen for food allergies.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
To evaluate apparent diffusion coefficient (ADC) and its standard deviation (SD
) in preoperative predicting liver invasion by T3-staged gallbladder carcinoma (GBC).
Forty-one consecutive patients ...with T3-staged resectable GBC were included and divided into two sets with (n=27) and without (n=14) liver invasion. All patients underwent DWI at b-values of 0, 20, 50, 80, 100, 200, 400, 600, 800, and 1,000 s/mm
with a 3 T magnetic resonance imaging scanner before surgery. ADC and SD
of tumour-adjacent and tumour-distant liver tissues were measured on DWI, and were compared by Mann-Whitney U-tests. If there was a significant difference in any derived parameter, the area under the receiver operating characteristic curve (AUC) was used to assess performance of this parameter to predict liver invasion.
DWI could differentiate between patients with and without liver invasion when b = 0, 1,000 s/mm
(AUCs of ADC and SD
were 0.697 and 0.714, respectively). In patients with liver invasion, mean ADC and SD
of tumour-adjacent liver tissue were lower than of tumour-distant liver tissue when b = 0, 800 s/mm
, and = 0, 1,000 s/mm
(all p-values <0.05). To differentiate tumour-adjacent from tumour-distant liver tissues in patients with liver invasion, AUCs of ADC were 0.687 (b = 0, 800 s/mm
) and 0.680 (b = 0, 1,000 s/mm
), and AUCs of SD
were 0.673 (b = 0, 800 s/mm
) and 0.731 (b = 0, 1,000 s/mm
).
DWI could have potential value in preoperative predicting liver invasion by T3-staged GBC.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Magnetic topological semimetals, a novel state of quantum matter with a nontrivial band topology, have emerged as a new frontier in physics and materials science. An external stimulus such as ...temperature or magnetic field could be expected to alter their spin states and thus Fermi surface anisotropies and topological features. Here, we perform angular magnetoresistance measurements and electronic band structure calculations to reveal the evolution of HoSb's Fermi surface anisotropies and topological nature in different magnetic states. The angular magnetoresistance results show that its Fermi surface anisotropy is robust in the paramagnetic state but is significantly modulated in the antiferromagnetic and ferromagnetic states. More interestingly, a transition from the trivial (nontrivial) to nontrivial (trivial) topological electronic phase is observed when HoSb undergoes a magnetic transition from the paramagnetic (antiferromagnetic) to antiferromagnetic (ferromagnetic) state induced by temperature (applied magnetic field). Our study suggests that HoSb provides an archetype platform to study the correlations between magnetism and topological states of matter.
The topological nature of electronic states in HoSb significantly depends on spin orderings (NM, AFM or FM spin configuration). Only the electronic band structure in HoSb's antiferromagnetic state is confirmed to be topologically nontrivial.
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