A
bstract
We consider an extension of the Standard Model with a complex singlet scalar, where a global U(
1
) symmetry is explicitly broken to ℤ
3
symmetry. We study the two-step electroweak phase ...transition in the model and find that it can be of first-order if the heavy scalar mass falls in the range of 1–2 TeV and the mixing angle |
θ
| ≳ 0
.
2 (11
.
5
°
). The Higgs signal strength measurements at the LHC, on the other hand, restrict the mixing angle |
θ
| ≲ 0
.
4 (23
°
). Future colliders including high-luminosity LHC can probe the remaining parameter space of first-order phase transition in this scenario. After the U(
1
) symmetry breaking, the pseudo-Goldstone boson becomes a dark matter candidate due to a hidden ℤ
2
symmetry of the model. We find that the pseudo-Goldstone boson can make up a small fraction of the observed dark matter and escape from the constraints of current direct detection. We also show that the stochastic gravitational wave signals from the phase transition are potentially discoverable with future space-based interferometers.
Materials with ultralong phosphorescence have wide-ranging application prospects in biological imaging, light-emitting devices, and anti-counterfeiting. Usually, molecular phosphorescence is ...significantly quenched with increasing temperature, rendering it difficult to achieve high-efficiency and ultralong room temperature phosphorescence. Herein, we spearhead this challenging effort to design thermal-quenching resistant phosphorescent materials based on an effective intermediate energy buffer and energy transfer route. Co-crystallized assembly of zero-dimensional metal halide organic-inorganic hybrids enables ultralong room temperature phosphorescence of (Ph
P)
Cd
Br
that maintains luminescent stability across a wide temperature range from 100 to 320 K (ΔT = 220 °C) with the room temperature phosphorescence quantum yield of 62.79% and lifetime of 37.85 ms, which exceeds those of other state-of-the-art systems. Therefore, this work not only describes a design for thermal-quenching-resistant luminescent materials with high efficiency, but also demonstrates an effective way to obtain intelligent systems with long-lasting room temperature phosphorescence for optical storage and logic compilation applications.
•Proposed two key performance indicators (KPIs) to monitor soft sensors for possible extrapolation or performance degradation.•Proposed updating the mean and variance of inputs and output to the PLS ...model while maintaining the same inner latent relationship to improve soft sensor performance.•Proposed a soft sensor maintenance method using the two KPIs to selectively perform mean and variance update to prolong soft sensor lifespan while minimizing model refitting.•The proposed maintenance strategy was tested using real industrial process data in several scenarios and demonstrated to be a robust mechanism to prolong soft sensor lifespans.
With the increasing availability of spectral, vibrational, thermal and other sensors, the challenge of “Big Data” in chemical processing industry is not only to analyze the data offline, but also to make use of the data online to improve process operation. To this end, accurate and reliable measurements or estimations of product quality are critical in today’s demanding manufacturing environments. Data-driven soft sensors based on Projection to Latent Structure (PLS) methods are often used to model key quality variables using measureable inputs. However, most processes do not operate around a true steady state due to changes in equipment, feedstock, sensor and operating strategy. Therefore, soft sensor models need to be updated periodically. Current model maintenance approaches such as moving window update, recursive update in industry center around rebuilding the model using more recent process data. This approach is not robust enough in scenarios where process data is contaminated with outliers, downtime and other non-steady state transients. In this study, an alternative model update approach is developed. First, we adapted two key performance indicators (KPIs) for assessing the performance of the current soft sensor model. The Hotelling’s T2 based KPI is a predictive KPI that monitors for model extrapolations against future process data; the prediction residual based KPI then detects long term prediction degradation trends using a filtered prediction error. Second, we developed an update strategy using the robust mean and variance estimators of the inputs and outputs. Through case studies using industrial process data, this update method was demonstrated to be effective in improving prediction performance without rebuilding the PLS model from scratch. Lastly, the model update mechanism can be combined with both KPIs indicators. Through simulation of online behavior using industrial data, we showed that this update strategy effectively improved the prediction performance of the PLS soft sensor. In cases where the initial model was suboptimal, the update strategy also allowed for timely identification of underlying problems and alerted engineers of the need to rebuild the model.
Atherosclerosis is a progressive, chronic inflammation in arterial walls. Long noncoding RNAs (lncRNAs) participate in inflammation, but the exact mechanism in atherosclerosis is unclear. Our ...microarray analyses revealed that the levels of lncRNA-FA2H-2 were significantly decreased by oxidized low-density lipoprotein (OX-LDL). Bioinformatics analyses indicated that mixed lineage kinase domain-like protein (MLKL) might be regulated by lncRNA-FA2H-2. In vitro experiments showed that lncRNA-FA2H-2 interacted with the promoter of the MLKL gene, downregulated MLKL expression, and the binding sites between -750 and 471 were necessary for lncRNA-FA2H-2 responsiveness to MLKL. Silencing lncRNA-FA2H-2 and overexpression of MLKL could activate inflammation and inhibited autophagy flux. Both lncRNA-FA2H-2 knockdown and overexpression of MLKL could significantly aggravate inflammatory responses induced by OX-LDL. We found that the 3-methyladenine (3-MA) and Atg7-shRNA enhanced inflammatory responses induced by knockdown of lncRNA-FA2H-2 and overexpression of MLKL. We demonstrated that the effects of MLKL on autophagy might be associated with a mechanistic target of rapamycin (mTOR)-dependent signaling pathways. In vivo experiments with apoE knockout mice fed a western diet demonstrated that LncRNA-FA2H-2 knockdown decreased microtubule-associated expression of microtubule-associated protein 1 light chain 3 II and lysosome-associated membrane protein 1, but increased expression of sequestosome 1 (p62), MLKL, vascular cell adhesion molecule-1, monocyte chemoattractant protein-1, and interleukin-6 in atherosclerotic lesions. Our findings indicated that the lncRNA-FA2H-2-MLKL pathway is essential for regulation of autophagy and inflammation, and suggested that lncRNA-FA2H-2 and MLKL could act as potential therapeutic targets to ameliorate atherosclerosis-related diseases.
An extreme positive Indian Ocean Dipole (IOD) event occurred in 2019 boreal autumn, which has induced severe climate impacts around the Indian Ocean basin. In this study, the cause for 2019 IOD event ...and the related mechanism are explored. We find that the remarkable strengthening of Australian high and weakening of sea level pressure over South China Sea/Philippine Sea have been evidently visible since May 2019. Such a record‐breaking interhemispheric pressure gradient (IHPG) induced northward cross‐equatorial flow over the western Maritime Continent, which triggered strong wind‐evaporation‐SST and thermocline feedbacks in 2019. In addition to 2019 case, historical IOD events are highly correlated with IHPG from boreal late spring to summer. We show that skillful IHPG prediction can be made in March by European Centre for Medium‐Range Weather Forecasts seasonal forecast system, which makes it quite possible for the early warning of extreme IOD events by two to three seasons ahead.
Plain Language Summary
During 2019 fall, an extreme Indian Ocean Dipole (IOD) event occurred. In this paper, the possible cause and mechanism of this event are investigated. We find that Australian high was strengthened, and Philippine Sea Anticyclone was weakened since May 2019. This interhemispheric sea level pressure gradient (IHPG) anomaly generates the northward cross equator over the Maritime Continent, which is crucial for the IOD growth. Not only for 2019 IOD, IHPG is a good indicator for almost all the IOD events in history. Since IHPG is predictable in March, the early warning of IOD events and resultant climate disasters could be possible.
Key Points
An extreme positive Indian Ocean Dipole (IOD) event occurred in 2019
The interhemispheric sea level pressure gradient (IHPG) across the Maritime Continent is suggested to be the cause of this IOD event
The skillful prediction of IHPG could give rise to the successful IOD prediction by two to three seasons ahead
A
bstract
It is widely believed that extensions of the minimal Higgs sector is one of the promising directions for resolving many puzzles beyond the Standard Model (SM). In this work, we study the ...unitarity bounds on the models by extending the two-Higgs-doublet model with an additional real or complex Higgs triplet scalar. By noting that the SM gauge symmetries SU(2)
L
× U(1)
Y
are recovered at high energies, we can classify the two-body scattering states by decomposing the direct product of two scalar multiplets into their direct sum of irreducible representations of electroweak gauge groups. In such state bases, the s-wave amplitudes of two-body scalar scatterings can be written in the form of block-diagonalized scattering matrices. Then the application of the perturbative unitarity conditions on the eigenvalues of scattering matrices leads to the analytic constraints on the model parameters. Finally, we numerically investigate the complex triplet scalar extension of the two-Higgs-doublet model, finding that the perturbative unitarity places useful stringent bounds on the model parameter space.
The extensively developed ene‐type enantioselective cycloisomerization of classical 1,n‐enynes provides an efficient approach to chiral cyclic 1,4‐dienes. In contrast, the catalytic asymmetric ...heteroarenyne (heteroarene–alkyne) cycloisomerization involving the dearomative transformation of endocyclic aromatic C=C bonds remains unknown. Herein, we communicate a PdH‐catalyzed enantioselective heteroarenyne cycloisomerization reaction of alkyne‐tethered indole substrates (formal 1,5‐ and 1,6‐enynes). Based on this strategy, a variety of structurally diverse chiral spiro and fused indoline derivatives bearing quaternary stereocenters and exocyclic C=C bonds are afforded in moderate to excellent yields and excellent enantioselectivities (up to 98 % ee). The classical ene‐type enantioselective 1,5‐enyne cycloisomerization of N‐vinylpropiolamides is also developed to afford chiral 2‐pyrrolones in good to excellent ee values.
A palladium‐catalyzed enantioselective ene‐type cycloisomerization of heteroarenynes has been developed with alkyne‐tethered indoles as substrates. The reaction provides an efficient avenue for the synthesis of structurally diverse indolines bearing quaternary stereocenters in moderate to excellent yields and excellent enantioselectivities (up to 98 % ee).
Summary
Cataract is one of the most important causes of blindness worldwide, with age‐related cataract being the most common one. Agents preventing cataract formation are urgently required. ...Substantial evidences point out aggravated oxidative stress as a vital factor for cataract formation. Nuclear factor (erythroid‐derived 2)‐like 2 (Nrf2)/Kelch‐like erythroid‐cell‐derived protein with CNC homology (ECH)‐associated protein 1 (Keap1) system is considered as one of the main cellular defense mechanisms against oxidative stresses. This review discusses the role of Nrf2 pathway in the prevention of cataracts and highlights that Nrf2 suppressors may augment oxidative stress of the lens, and Nrf2 inducers may decrease the oxidative stress and prevent the cataract formation. Thus, Nrf2 may serve as a promising therapeutic target for cataract treatment.
We present in this paper a short-term scheduling of battery in security-constrained unit commitment (SCUC). For economical operation and control purposes, electric power users with photovoltaic ...(PV)/battery systems are interested in the availability and the dispatch of PV/battery power on an hourly basis, which is a cumbersome task due to the complicated operating patterns of PV/battery. The details of battery model in the PV/battery system are presented in this paper. The paper applies a Lagrangian relaxation-based optimization algorithm to determine the hourly charge/discharge commitment of battery in a utility grid. The paper also applies a network flow programming algorithm for the dispatch of committed battery units. The paper analyzes the impact of grid-connected PV/battery system on locational pricing, peak load shaving, and transmission congestion management. An eight-bus test system is used to study the operational pattern of aggregated PV/battery and demonstrate the advantages of utilizing PV/battery systems in the electric utility operation.
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