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Sagnac interference experiment is theoretically analyzed in the curved spacetime of the Rotating Acoustic Black hole metric. The Zero and the infinite Sagnac delay has been analyzed. The geodesic motion in the metric is discussed very briefly to derive the formula for the Sagnac delay. For the first time, the values of the two constant parameters related to the metric of the acoustic black hole have been found to be restricted within certain limit by the use of the formula for the Sagnac delay. The equation for finding the sonic horizon has also been deduced. [ABSTRACT FROM AUTHOR]

The Mg ii k and h line intensity ratios can be used to probe the characteristics of the plasma in the solar atmosphere. In this study, using the observations recorded by the Interface Region Imaging Spectrometer, we study the variation of the Mg ii k and h intensity ratio for three flares belonging to X-class, M-class, and C-class, throughout their evolution. We also study the k-to - h intensity ratio as a function of magnetic flux density obtained from the line-of-sight magnetograms recorded by the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory. Our results reveal that, while the intensity ratios are independent of magnetic flux density, they show significant changes during the evolution of the C-class and M-class flares. The intensity ratios start to increase at the start of the flare and peak during the impulsive phase before the flare peak and decrease rapidly thereafter. The values of the ratios fall even below the preflare level during the peak and decline phases of the flare. These results are important in light of heating and cooling of localized plasma and provide further constraint on the understanding of flare physics. [ABSTRACT FROM AUTHOR]

• Hemispheric prediction of solar cycle 25 has been done using sunspot number data. • Deep Learning algorithm has been used for the purpose of prediction. • Method of Expanding widow has been used for cross-validation. • Validation of model performance has been done by predicting past solar cycles 20–24. • Developed model achieves a high degree of accuracy in hemispheric prediction of cycle 25. In the current work, single-and double-layered Long Short-Term Memory (LSTM) model have been developed and compared to find the most suitable one for hemispheric prediction of solar cycle 25. The smoothed Hemispheric Sunspot Number (HSN) reconstructed by Veronig et al. (2021) has been used to achieve the objective. The deep learning models are evaluated over different pairs of train and test set for both the hemispheres using the 5-fold cross-validation scheme, to determine the best effective model for hemispheric prediction of cycle 25. Our analysis reveals that the single-layered LSTM model achieves lower RMSE when predicting the test dataset. To prove the reliability of our suggested LSTM models, we have predicted the hemispheric profiles of solar cycles 21–24. From our analysis, we found that the single-layered LSTM model performed better in comparison to the double-layered LSTM model in predicting past solar cycles 21–24. Hence, hemispheric prediction of solar cycle 25 is carried out utilizing the single-layered LSTM model due to better performance capability during experimental analysis. This work founds that the northern hemisphere will peak with an amplitude of 56 ± 5 during July 2023 + 3 months while the southern hemisphere will have a maximum amplitude of 54 ± 4 during June 2023 + 2 months. So, it can be said that the southern HSN will peak before the northern HSN and that the peak of northern HSN will be slightly higher than the southern one. [ABSTRACT FROM AUTHOR]

We have developed a novel visible‐light‐catalyzed bioconjugation reaction, PhotoCLIC, that enables chemoselective attachment of diverse aromatic amine reagents onto a site‐specifically installed 5‐hydroxytryptophan residue (5HTP) on full‐length proteins of varied complexity. The reaction uses catalytic amounts of methylene blue and blue/red light‐emitting diodes (455/650 nm) for rapid site‐specific protein bioconjugation. Characterization of the PhotoCLIC product reveals a unique structure formed likely through a singlet oxygen‐dependent modification of 5HTP. PhotoCLIC has a wide substrate scope and its compatibility with strain‐promoted azide‐alkyne click reaction, enables site‐specific dual‐labeling of a target protein. [ABSTRACT FROM AUTHOR]

We have developed a novel visible‐light‐catalyzed bioconjugation reaction, PhotoCLIC, that enables chemoselective attachment of diverse aromatic amine reagents onto a site‐specifically installed 5‐hydroxytryptophan residue (5HTP) on full‐length proteins of varied complexity. The reaction uses catalytic amounts of methylene blue and blue/red light‐emitting diodes (455/650 nm) for rapid site‐specific protein bioconjugation. Characterization of the PhotoCLIC product reveals a unique structure formed likely through a singlet oxygen‐dependent modification of 5HTP. PhotoCLIC has a wide substrate scope and its compatibility with strain‐promoted azide‐alkyne click reaction, enables site‐specific dual‐labeling of a target protein. [ABSTRACT FROM AUTHOR]

Signal Amplification by Reversible Exchange (SABRE) is an inexpensive and simple hyperpolarization technique that is capable of boosting nuclear magnetic resonance sensitivity by several orders of magnitude. It utilizes the reversible binding of para-hydrogen, as hydride ligands, and a substrate of interest to a metal catalyst to allow for polarization transfer from para-hydrogen into substrate nuclear spins. While the resulting nuclear spin populations can be dramatically larger than those normally created, their lifetime sets a strict upper limit on the experimental timeframe. Consequently, short nuclear spin lifetimes are a challenge for hyperpolarized metabolic imaging. In this report, we demonstrate how both hyperpolarization and long nuclear spin lifetime can be simultaneously achieved in nitrogen-15 containing derivatives of pyridazine and phthalazine by SABRE. These substrates were chosen to reflect two distinct classes of 15N2-coupled species that differ according to their chemical symmetry and thereby achieve different nuclear spin lifetimes. The pyridazine derivative proves to exhibit a signal lifetime of ∼2.5 min and can be produced with a signal enhancement of ∼2700. In contrast, while the phthalazine derivative yields a superior 15 000-fold 15N signal enhancement at 11.7 T, it has a much shorter signal lifetime. [ABSTRACT FROM AUTHOR]

For better performance in any team sport, team managers assess the match conditions, and opponents' strengths and weaknesses to select the best team possible. In cricket, existing studies focus on the effect of contextual factors such as home advantage, toss win, and toss decision, among others, on team performance. However, very few studies discuss the factors' relative importance or the extent of their impact on performance. There is also a lack of studies addressing the best situational decisions to be taken by teams, given certain opponents and match conditions. This study aims to determine the effect of contextual factors and subsequent decisions taken on team performance in Twenty20 (T20) cricket. Match-wise data for nine seasons of the Indian premier league consisting of 563 matches were considered, and tree-based machine learning (ML) models such as gradient boosting, regression tree, bagging, random forest, and bayesian additive regression tree (BART) were employed for data analysis. BART produced the most efficient results, which were further interpreted using Interpretable ML methods such as partial dependence plots and accumulated local effects to determine the most critical factors affecting team performance. Additionally, these findings were used to obtain optimal pre-match decisions and pre-season strategies to achieve higher performance, which could serve as a decision support system for teams in T20 cricket. [ABSTRACT FROM AUTHOR]

In this article, we present statistical inference of unknown lifetime parameters based on a progressive Type‐I interval censored dataset in presence of independent competing risks. A progressive Type‐I interval censoring scheme is a generalization of an interval censoring scheme, allowing intermediate withdrawals of test units at the inspection points. We assume that the lifetime distribution corresponding to a failure mode belongs to a log‐location‐scale family of distributions. Subsequently, we present the maximum likelihood analysis for unknown model parameters. We observe that the numerical computation of the maximum likelihood estimates can be significantly eased by developing an expectation‐maximization algorithm. We demonstrate the same for three popular choices of the log‐location‐scale family of distributions. We then provide Bayesian inference of the unknown lifetime parameters via Gibbs Sampling and a related data augmentation scheme. We compare the performance of the maximum likelihood estimators and Bayesian estimators using a detailed simulation study. We also illustrate the developed methods using a progressive Type‐I interval censored dataset. [ABSTRACT FROM AUTHOR]

An extended version of task group report (TG)‑119 dosimetric tests was introduced and tested on the TrueBeam linear accelerator setup. Treatment plan results and quality assurance (QA) results of RapidArc (RA) and intensity‑modulated radiotherapy (IMRT) were compared to understand the limitation and efficacy of the RA and IMRT system of the linear accelerator. Test structure sets were drawn on OCTAVIUS four‑dimensional (4D) phantom computed tomography scan data for this study. We generated treatment plans based on the specified goal in the Eclipse™ treatment planning system using RA and IMRT in the study phantom. We used the same planning objectives for RA and IMRT techniques. Planar dose verification was performed using electronic portal imaging device and OCTAVIUS 4D phantom. The treatment log file was further analyzed using Pylinac (V2.4.0 (Open Source Code library available on Github, runs under Python programming language)) to compare the dosimetric outcome of RA and IMRT. Dose to the planning target volume (PTV) 1–5 and organ at risk (OAR) were analyzed in this study for the efficiency comparison of RA and IMRT. The primary objective was accomplished by adhering to the dose constraints associated with PTV 2 and the OAR. RA and IMRT also met the secondary objective. The tertiary goal of dose delivery to PTV 4 was met with RA but not IMRT. This study can be utilized to compare different institutions’ planning and patient‑specific QA (PSQA) procedures. The findings of this study were in line with the published works of the literature. A multi‑institutional planning and delivery accuracy audit can be built using this structure and set of planning objectives having similar PSQA phantom. The TG‑119 report incorporated test challenges that were combined in a single study set and a single plan. This reduces the complexity of performing the original TG‑119 tests, whereas keeping the challenges as introduced in the TG‑119 report. This study’s planning and dosimetric results could be further utilized for dosimetry audit with any institute having a linear accelerator and OCTAVIUS 4D phantom for PSQA. [ABSTRACT FROM AUTHOR]

A deep-learning Vanilla, or single layer, Long Short-Term Memory model is proposed for improving the prediction of Solar Cycle 25. WDC-SILSO the Royal Observatory of Belgium, Brussels provides the 13-month smoothed sunspot-number data that were used to make this prediction. The root mean square error (RMSE) obtained by the proposed model, which is improved in comparison to the existing stacked LSTM model, lies within the range of 1.65 – 4.92, according to analysis on a number of temporal intervals taken into consideration in this study. The model performance has been validated by forecasting the peak amplitude of Solar Cycles 21 – 24. It is shown that for Cycles 21 and 22, the prediction error in estimating the peak is 1.159% and 0.423%, while the RMSE is estimated to be 4.149 and 3.274, respectively. For Cycle 23, the relative error and RMSE are 1.054% and 2.985, respectively, whereas for Cycle 24 they are 1.117% and 3.406, respectively. The current proposed model has exactly predicted the timing when the SSN reached its maximum for Cycle 23. While for Cycle 21, the prediction has a 1-month delay from the actual timing. For Cycles 22 and 24, the year during which the SSN reached maximum coincides with the observed year, although their month of peak occurrence showed a difference of three months and one month, respectively. The current proposed model suggests that the Cycle 25 will peak in April 2023 with an amplitude value of 136.9, which will be approximately 17.68% stronger compared with Cycle 24. [ABSTRACT FROM AUTHOR]

This paper investigates the North–South (N–S) as well as East–West (E–W) distribution and asymmetry in Soft X-ray flares (SXR) activity during the period 1976–2019 which corresponds to solar cycles 21–24. Our results reveal that, cycles 21, 22 and 23 are dominated by southern hemisphere and the cycle 24 is also found to be southern hemisphere dominated using soft X-ray flares data. The cumulative plot indicates a slight excess of X-ray flare events in the southern hemisphere during solar cycles 21, 23 and 24. A significant excess of flare events in the southern hemisphere has been observed in the cumulative plot during cycle 22. The most prolific latitude band in the N–S distribution is the 10°–20° which produced maximum number of soft X-ray flares over solar cycles 21, 22, 23 and 24 whereas no such longitudinal band is observed in the E–W distribution. The time-latitude plot of SXR flares is also constructed to study the behaviour of N–S distribution. It is also revealed in current work that the occurrence (number) of M and X class flares is showing a declining trend since solar cycle 21 till solar cycle 24 thereby violating the Gnevyshev-Ohl (G-O) rule. A significant eastern dominance is being observed till solar cycle 23 but the predominance shifted to western hemisphere during cycle 24. Our analysis reveals that the North–South asymmetry is highly significant in comparison to East–West asymmetry. [ABSTRACT FROM AUTHOR]

Food waste is a serious problem affecting societies and contributing to climate change. About one-third of all food produced globally is wasted, while millions of people remain food insecure. Food-sharing apps attempt to simultaneously address ‘hunger’ and ‘food waste’ at the community level. Though highly beneficial, these apps experience low usage. Existing studies have explored multiple challenges affecting food-sharing usage, but are constrained by limited data and narrow geographical focus. To address this gap, this study analyzes online user reviews from top food-sharing apps operating globally. A unique approach of analyzing text data with interpretable machine learning (IML) tools is utilized. Eight challenges affecting food-sharing app usage are obtained using the topic modeling approach. Further, the review scores representing user experience (UX) are assessed for their dependence on each challenge using the document-topic matrix and machine learning (ML) procedures. Tree-based ML algorithms, namely regression tree, bagging, random forest, boosting, and Bayesian additive regression tree are employed. The best-performing algorithm is then complemented with IML tools such as accumulated local effects and partial dependence plots, to assess the impact of each challenge on UX. Critical improvement areas to increase food-sharing apps’ usage are highlighted, such as service responsiveness, app design, food variety, and unethical behavior. This study contributes to the nascent literature on food-sharing and IML applications. A significant advantage of the methodological approach utilized includes better explainability of ML models involving text data, at both the global and local interpretability levels, in terms of the associated features and feature interactions. [ABSTRACT FROM AUTHOR]

Nuclear spin hyperpolarization transforms typically weak NMR responses into strong signals paving the way for low-gamma nuclei detection within practical time-frames. SABRE (Signal Amplification by Reversible Exchange) is a particularly popular hyperpolarization technique due to its simplicity but the pool of molecules it can polarize is limited. The recent advancement in the form of co-ligands has made SABRE applicable towards molecules with O-donor sites e.g. pyruvate, a key step towards its potential clinical application. Here we explore the SABRE hyperpolarization of another compound with an alpha-keto motif, namely oxalate. We show that hyperpolarization of oxalate may be achieved by adjusting the pH in the presence of sulfoxide co-ligands. The SABRE effect for oxalate in methanol solutions is most effective for the mono-protonated form, which is dominant in the solution around pH ∼2.8. The polarization levels become markedly lower at both higher and lower pH. Employing 50% enriched pH2 we achieve up to 0.33% net 13C polarization in mono-protonated oxalate. In an alternative procedure we show that the hyperpolarization effect in oxalates can also be realised by synthesizing an esterified version of it, without any substantive pH implications. Further, the procedures to create hyperpolarized singlet orders in such substrates are also investigated. [ABSTRACT FROM AUTHOR]

• Peak & timing of solar cycle 25 has been predicted using sunspot number data. • The concept of Deep Learning algorithm has been used for forecasting. • The proposed model showed good performance on various time intervals with low RMSE value. • Validation of model performance has been done by predicting past solar cycles 20–24. • The model captured non-linearity and cyclic trend within the data with good RMSE. In the current work we have used the deep learning based long short-term memory model to predict the strength and peak time of solar cycle 25 by employing the monthly smoothed sunspot number data obtained from WDC-SILSO, Royal Observatory of Belgium, Brussels. We have used the stacked LSTM forecasting model to predict the upcoming cycle 25. From our analysis it has been shown that our proposed model is capable of capturing long term dependencies as well as trend within the data. For cycle 20 and 21 the error difference between predicted as well as observed peak value is 2.3 and 0.7 respectively while the peak prediction error is 1.47% and 0.30%. The RMSE of the model for cycle 20 and 21 is 3.97 and 4.34 respectively. For cycle 22, the AE and RE is 4.6 and 2.16% while the RMSE of the model for this case is 4.50. The predicted peak amplitude of solar cycle 23 and 24 from our proposed model has a relative error of 1.75% and 1.99% respectively from the observed value while the RMSE is 3.4 for cycle 23 and 4.2 for cycle 24. Our projected prediction of cycle 25 using the proposed LSTM model, says that it will be stronger than cycle 24 and weaker than cycle 23. The solar cycle 25 will peak with an amplitude of sunspot number at 171.9 ± 3.4 and will be 47 % stronger than cycle 24. The solar cycle 25 will reach its peak in August 2023 ± 2 months. [ABSTRACT FROM AUTHOR]

Aim: To determine the multileaf collimator positional error (MLC-PE) during volumetric modulated arc therapy (VMAT) delivery by studying the time-dependent MLC velocity in mathematically derivable trajectories such as straight line and conic sections. Materials and Methods: VMAT delivery is planned in a way that MLCs are moving in a locus which can be defined by mathematical functions such as linear, parabolic, or circular velocity (PV or CV). The VMAT delivery was interrupted either once or multiple times during the delivery and projection images of the same were acquired in electronic portal imaging device. MLC-PE was then analyzed as a function of dose rate (DR), and MLC speed (SP) and number of interruptions in treatment delivery. In VMAT delivery with linear MLC motion, the delivery was interrupted either once (linear motion single interruption) or multiple (three) times (linear motion multiple interruptions). For PV and CV MLC velocity, the MLC motions are interrupted multiple times. Results: The maximum individual error obtained (DR of 35 MU/min, SP of 2.0 cm/s) was 1.96 ± 0.1 mm. Only 4.4% of MLCs showed ≥ ±1 mm positional error. When the treatment delivery is interrupted multiple times in VMAT delivery, the influence of interruption in MLC-PE overwhelmed the influence by DR and SP. For a sub-group analysis of independent and dependent variables, the mean MLC-PE was 0.18 ± 0.4 mm 0.19 ± 0.42 mm, respectively. Conclusion: Determination of MLC-PEs using a mathematical function without approximation indicates that MLC-PE is not a function of MLC speed. In less than 5% of the studied scenarios, the MLC-PE exceeds its tolerance value (±1 mm). The MLC-PE is significantly less in modern machines due to advancements in the delivery mechanism. [ABSTRACT FROM AUTHOR]

In the current investigation we have studied the distribution as well as the asymmetry of solar X-ray flares during the period 1976–2017 which corresponds to solar cycle 21, 22, 23 and the almost complete solar cycle 24. The study of the N–S distribution of soft X-ray flares during solar cycles 21, 22, 23 and 24 reveals that the 10°–20° latitude band produced maximum number of soft X-ray flares and is found to be southern hemisphere dominated during all the considered cycles. The soft X-ray flares events above 40° latitude is very rare. Most of the solar X-ray flare activities are observed to be concentrated in the 8°–30° latitude band. A time-latitude plot has been plotted to graphically represent the soft X-ray flare distribution at various latitudes over the course of solar cycle. Our analysis also reveals that solar cycles 21, 22 and 23 are southern hemisphere dominated and the corresponding probability value is statistically significant. The soft X-ray solar flare activity during solar cycle 24 is also found to be southern hemisphere dominated, similar to cycles 21, 22 and 23. Using cross-correlation analysis, we have found that the smoothed curves of the number of soft X-ray flares in northern hemisphere are ahead of the southern hemisphere by 10 months, 2 months, 8 months and 4 months during solar cycles 21, 22, 23 and 24 respectively. Also, for total time span (1976–2017), the smoothed curve of the frequency of soft X-ray flares in northern hemisphere is ahead of a similar curve from the southern hemisphere by 7 months. [ABSTRACT FROM AUTHOR]

To investigate the effect of feedback from active galactic nuclei (AGN) on their surrounding medium, we study the diffuse X‐ray emission from galaxy groups and clusters by coupling the Astrophysical Plasma Emission Code (APEC) with the cosmological hydrodynamic simulation involving AGN feedback. We construct a statistical sample of synthetic Chandra X‐ray photon maps to observationally characterize the effect of AGN on the ambient medium. We show that AGN are effective in displacing the hot X‐ray emitting gas from the centers of groups and clusters, and that these signatures remain evident in observations of the X‐ray surface brightness profiles. [ABSTRACT FROM AUTHOR]

Hyperpolarisation methods that premagnetise agents such as pyruvate are currently receiving significant attention because they produce sensitivity gains that allow disease tracking and interrogation of cellular metabolism by magnetic resonance. Here, we communicate how signal amplification by reversible exchange (SABRE) can provide strong 13C pyruvate signal enhancements in seconds through the formation of the novel polarisation transfer catalyst [Ir(H)2(η2‐pyruvate)(DMSO)(IMes)]. By harnessing SABRE, strong signals for [1‐13C]‐ and [2‐13C]pyruvate in addition to a long‐lived singlet state in the [1,2‐13C2] form are readily created; the latter can be observed five minutes after the initial hyperpolarisation step. We also demonstrate how this development may help with future studies of chemical reactivity. [ABSTRACT FROM AUTHOR]

Hyperpolarisation methods that premagnetise agents such as pyruvate are currently receiving significant attention because they produce sensitivity gains that allow disease tracking and interrogation of cellular metabolism by magnetic resonance. Here, we communicate how signal amplification by reversible exchange (SABRE) can provide strong 13C pyruvate signal enhancements in seconds through the formation of the novel polarisation transfer catalyst [Ir(H)2(η2‐pyruvate)(DMSO)(IMes)]. By harnessing SABRE, strong signals for [1‐13C]‐ and [2‐13C]pyruvate in addition to a long‐lived singlet state in the [1,2‐13C2] form are readily created; the latter can be observed five minutes after the initial hyperpolarisation step. We also demonstrate how this development may help with future studies of chemical reactivity. [ABSTRACT FROM AUTHOR]

• Optimal Bayesian life tests plans are presented under Progressive Type-I Interval Censoring Scheme. • Bayesian C -optimal design criterion is used. • An algorithm is presented for log-location-scale family of distributions. • A comparative study is provided for Weibull and log-normal lifetime distributions. • Sampling variations are visualized through MCMC methods. This work considers optimal planning of progressive type-I interval censoring schemes for log-location-scale family of distributions. Optimum schemes are obtained by using a Bayesian C -optimality design criterion. The C -optimality criterion is formed to attain precision in estimating a particular lifetime quantile. An algorithm is proposed to obtain the optimal censoring schemes. Optimal schemes are obtained under two different scenarios for the Weibull and log-normal models, which are two popular special cases of log-location-scale family of distributions. A sensitivity analysis is conducted to study the effect of various prior inputs on the optimal censoring schemes. Furthermore, a simulation study is undertaken to illustrate the sampling variations resulting from the optimal censoring schemes. [ABSTRACT FROM AUTHOR]

The radio frequency emission at 10.7 cm (or 2800 MHz) wavelength (considered as solar flux density) out of different possible wavelengths is usually selected to identify periodicities because of its high correlation with solar extreme ultraviolet radiation as well as its complete and long observational record other than sunspot related indices. The solar radio flux at 10.7 cm wavelength plays a very valuable role for forecasting the space weather because it is originated from lower corona and chromospheres region of the Sun. Also, solar radio flux is a magnificent indicator of major solar activity. Here in the present work the solar radio flux data from 1965 to 2014 observed at the Domimion Radio Astrophysical Observatory in Penticton, British Columbiahas been processed using Date Compensated Discrete Fourier Transform (DCDFT) to identify predominant periods within the data along with their confidence levels. Also, the multi-taper method (MTM) for periodicity analysis is used to validate the observed periods. Present investigation exhibits multiperiodicity of the time series F10.7 solar radio flux data around 27, 57, 78, 127, 157, 4096 days etc. The observed periods are also compared with the periods of MgII Index data using same algorithm as MgII Index data has 99.9% correlation with F10.7 Solar Radio Flux data. It can be observed that the MgII index data exhibits similar periodicities with very high confidence levels.Present investigation also clearly indicates that the computed results are very much confining with the results obtained in different communication for the similar data of 10.7 cm Solar Radio Flux as well as for the other solar activities. [ABSTRACT FROM AUTHOR]

This article presents optimal Bayesian accelerated life test plans for series systems under Type-I censoring scheme. First, the component lifetimes are assumed to follow independent Weibull distributions. The scale parameters of Weibull lifetime distributions are related to the external stress variable through a general stress translation function. For a fixed number of design points, optimal Bayesian ALT plans are first obtained by solving constrained optimization problems under two different Bayesian design criteria. The global optimality of the resulting fixed-point optimal designs is then verified via the General Equivalence Theorem. This article also provides the optimized compromise ALT plans which are extremely useful in real-life applications. A detailed sensitivity analysis is then performed to find out the effect of various planning inputs on the resulting optimal Bayesian ALT plans. A simulation study is then conducted to visualize the resulting sampling variations from the optimal Bayesian ALT plans. Finally, this article considers a series system with dependent component lifetimes. Optimal ALT plans are obtained assuming a Gamma frailty model. [ABSTRACT FROM AUTHOR]

Scrub typhus is a re-emerging threat throughout the world. The spectra of clinical pictures and possible complications are both varied and being increasingly reported. Acute disseminated encephalomyelitis (ADEM) is an infrequent demyelinating disorder of the central nervous system that is precipitated by infections and immunizations. There are only two documented cases of ADEM-associated scrub typhus published in the medical literature. We report the first pediatric case wherein a 5-year-old boy presented with high fever, altered sensorium, seizure, quadriparesis, and neck rigidity. He was ultimately diagnosed as a case of scrub typhus with ADEM. After treatment with intravenous doxycycline and methylprednisolone, the fever subsided but residual neurodeficits, such as inability to sit, stand, and talk, as well as bowel bladder dysfunctions persisted. He was subsequently transferred to long-term rehabilitation care. [ABSTRACT FROM AUTHOR]

In many industrial applications, it is not always feasible to continuously monitor the life testing experiments to collect lifetime data. Moreover, intermediate removals of the test units from the life testing experiment are sometimes essential. Progressive Type-I interval censoring schemes are useful in these scenarios. Optimal planning of such progressive Type-I interval censoring schemes is an important issue to the experimenter, as the optimal plans can achieve the desired objectives using much lesser resources. This article provides Bayesian D-optimal progressive Type-I interval censoring schemes, assuming that the lifetime follows a log-normal distribution. An algorithm is provided to find the optimal censoring schemes and the number of inspections. The algorithm is then used to obtain the optimal Bayesian progressive Type-I interval censoring schemes in 2 different contexts. The resulting optimal Bayesian censoring schemes are compared with the corresponding locally optimal censoring schemes. A detailed sensitivity analysis is performed to investigate the effect of prior information. The sampling variation associated with the optimal censoring schemes is visualized through a simulation study. [ABSTRACT FROM AUTHOR]

Signal Amplification by Reversible Exchange (SABRE) is an attractive nuclear spin hyperpolarization technique capable of huge sensitivity enhancement in nuclear magnetic resonance (NMR) detection. The resonance condition of SABRE hyperpolarization depends on coherent spin mixing, which can be achieved naturally at a low magnetic field. The optimum transfer field to spin-1/2 heteronuclei is technically demanding, as it requires field strengths weaker than the earth’s magnetic field for efficient spin mixing. In this paper, we illustrate an approach to achieve strong 15 N SABRE hyperpolarization at high magnetic field by a radio frequency (RF) driven coherent transfer mechanism based on alternate pulsing and delay to achieve polarization transfer. The presented scheme is found to be highly robust and much faster than existing related methods, producing ∼ 3 orders of magnitude 15 N signal enhancement within 2 s of RF pulsing. [ABSTRACT FROM AUTHOR]

This article considers inference for the log-normal distribution based on progressive Type I interval censored data by both frequentist and Bayesian methods. First, the maximum likelihood estimates (MLEs) of the unknown model parameters are computed by expectationmaximization (EM) algorithm. The asymptotic standard errors (ASEs) of the MLEs are obtained by applying the missing information principle. Next, the Bayes' estimates of the model parameters are obtained by Gibbs sampling method under both symmetric and asymmetric loss functions. The Gibbs sampling scheme is facilitated by adopting a similar data augmentation scheme as in EM algorithm. The performance of theMLEs and various Bayesian point estimates is judged via a simulation study. A real dataset is analyzed for the purpose of illustration. [ABSTRACT FROM AUTHOR]

Nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) suffer from low sensitivity and limited nuclear spin memory lifetimes. Although hyperpolarization techniques increase sensitivity, there is also a desire to increase relaxation times to expand the range of applications addressable by these methods. Here, we demonstrate a route to create hyperpolarized magnetization in 13C nuclear spin pairs that last much longer than normal lifetimes by storage in a singlet state. By combining molecular design and low-field storage with para-hydrogen derived hyperpolarization, we achieve more than three orders of signal amplification relative to equilibrium Zeeman polarization and an order of magnitude extension in state lifetime. These studies use a range of specifically synthesized pyridazine derivatives and dimethyl p-tolyl phenyl pyridazine is the most successful, achieving a lifetime of about 190 s in low-field, which leads to a 13C-signal that is visible for 10 minutes. [ABSTRACT FROM AUTHOR]

Nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) are two extremely important techniques with applications ranging from molecular structure determination to human imaging. However, in many cases the applicability of NMR and MRI are limited by inherently poor sensitivity and insufficient nuclear spin lifetime. Here we demonstrate a cost-efficient and fast technique that tackles both issues simultaneously. We use the signal amplification by reversible exchange (SABRE) technique to hyperpolarize the target 1H nuclei and store this polarization in long-lived singlet (LLS) form after suitable radiofrequency (rf) pulses. Compared to the normal scenario, we achieve three orders of signal enhancement and one order of lifetime extension, leading to 1H NMR signal detection 15 minutes after the creation of the detected states. The creation of such hyperpolarized long-lived polarization reflects an important step forward in the pipeline to see such agents used as clinical probes of disease. [ABSTRACT FROM AUTHOR]

Nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) are two extremely important techniques with applications ranging from molecular structure determination to human imaging. However, in many cases the applicability of NMR and MRI are limited by inherently poor sensitivity and insufficient nuclear spin lifetime. Here we demonstrate a cost-efficient and fast technique that tackles both issues simultaneously. We use the signal amplification by reversible exchange (SABRE) technique to hyperpolarize the target 1H nuclei and store this polarization in long-lived singlet (LLS) form after suitable radiofrequency (rf) pulses. Compared to the normal scenario, we achieve three orders of signal enhancement and one order of lifetime extension, leading to 1H NMR signal detection 15 minutes after the creation of the detected states. The creation of such hyperpolarized long-lived polarization reflects an important step forward in the pipeline to see such agents used as clinical probes of disease. [ABSTRACT FROM AUTHOR]

The creation of magnetic states that have long lifetimes has been the subject of intense investigation, in part because of their potential to survive the time taken to travel from the point of injection in a patient to the point where a clinically diagnostic MRI trace is collected. We show here that it is possible to harness the signal amplification by reversible exchange (SABRE) process to create such states in a hyperpolarised form that improves their detectability in seconds without the need for any chemical change by reference to the model substrate 2-aminothiazole. We achieve this by transferring Zeeman derived polarisation that is 1500 times larger than that normally available at 400 MHz with greater than 90% efficiency into the new state, which in this case has a 27 second lifetime. [ABSTRACT FROM AUTHOR]

This paper provides methods of obtaining BayesianD-optimal Accelerated Life Test (ALT) plans for series systems with independent exponential component lives under the Type-I censoring scheme. Two different BayesianD-optimality design criteria are considered. For both the criteria, first optimal designs for a given number of experimental points are found by solving a finite-dimensional constrained optimization problem. Next, the global optimality of such an ALT plan is ensured by applying the General Equivalence Theorem. A detailed sensitivity analysis is also carried out to investigate the effect of different planning inputs on the resulting optimal ALT plans. Furthermore, these Bayesian optimal plans are also compared with the corresponding (frequentist) locallyD-optimal ALT plans. [ABSTRACT FROM PUBLISHER]

This article provides Bayesian analyses of data arising from multi-stress accelerated life testing of series systems. The component log-lifetimes are assumed to independently belong to some log-concave location-scale family of distributions. The location parameters are assumed to depend on the stress variables through a linear stress translation function. Bayesian analyses and associated predictive inference of reliability characteristics at usage stresses are performed using Gibbs sampling from the joint posterior. The developed methodology is numerically illustrated by analyzing a real data set through Bayesian model averaging of the two popular cases of Weibull and log-normal, with the later getting a special focus in this article as a slightly easier example of the log-location-scale family. A detailed simulation study is also carried out to compare the performance of various Bayesian point estimators for the log-normal case. [ABSTRACT FROM AUTHOR]

Quantum-rotor-induced polarisation (QRIP) enhancement is exhibited by substances which contain freely rotating methyl groups in the solid state, provided that the methyl groups contain a 13 C nucleus. Strong signal enhancements are observed in solution NMR when the material is first equilibrated at cryogenic temperatures, then rapidly dissolved with a warm solvent and transferred into an NMR magnet. QRIP leads to strongly-enhanced 13 C NMR signals, but relatively weak enhancements of the 1 H signals. We show that the 1 H signals suffer from a partial cancellation of degenerate contributions, which may be corrected by applying a frequency-selective π pulse to the inner peaks of the 13 C multiplet prior to 1 H observation. [ABSTRACT FROM AUTHOR]

Site‐specific incorporation of multiple distinct noncanonical amino acids (ncAAs) into proteins in mammalian cells is a promising technology, where each ncAA must be assigned to a different orthogonal aminoacyl‐tRNA synthetase (aaRS)/tRNA pair that reads a distinct nonsense codon. Available pairs suppress TGA or TAA codons at a considerably lower efficiency than TAG, limiting the scope of this technology. Here we show that the E. coli tryptophanyl (EcTrp) pair is an excellent TGA‐suppressor in mammalian cells, which can be combined with the three other established pairs to develop three new routes for dual‐ncAA incorporation. Using these platforms, we site‐specifically incorporated two different bioconjugation handles into an antibody with excellent efficiency, and subsequently labeled it with two distinct cytotoxic payloads. Additionally, we combined the EcTrp pair with other pairs to site‐specifically incorporate three distinct ncAAs into a reporter protein in mammalian cells. [ABSTRACT FROM AUTHOR]

Site‐specific incorporation of multiple distinct noncanonical amino acids (ncAAs) into proteins in mammalian cells is a promising technology, where each ncAA must be assigned to a different orthogonal aminoacyl‐tRNA synthetase (aaRS)/tRNA pair that reads a distinct nonsense codon. Available pairs suppress TGA or TAA codons at a considerably lower efficiency than TAG, limiting the scope of this technology. Here we show that the E. coli tryptophanyl (EcTrp) pair is an excellent TGA‐suppressor in mammalian cells, which can be combined with the three other established pairs to develop three new routes for dual‐ncAA incorporation. Using these platforms, we site‐specifically incorporated two different bioconjugation handles into an antibody with excellent efficiency, and subsequently labeled it with two distinct cytotoxic payloads. Additionally, we combined the EcTrp pair with other pairs to site‐specifically incorporate three distinct ncAAs into a reporter protein in mammalian cells. [ABSTRACT FROM AUTHOR]

Consider aJ-component series system which is put on Accelerated Life Test (ALT) involvingKstress variables. First, a general formulation of ALT is provided for log-location-scale family of distributions. A general stress translation function of location parameter of the component log-lifetime distribution is proposed which can accommodate standard ones like Arrhenius, power-rule, log-linear model, etc., as special cases. Later, the component lives are assumed to be independent Weibull random variables with a common shape parameter. A full Bayesian methodology is then developed by letting only the scale parameters of the Weibull component lives depend on the stress variables through the general stress translation function. Priors on all the parameters, namely the stress coefficients and the Weibull shape parameter, are assumed to be log-concave and independent of each other. This assumption is to facilitate Gibbs sampling from the joint posterior. The samples thus generated from the joint posterior is then used to obtain the Bayesian point and interval estimates of the system reliability at usage condition. [ABSTRACT FROM AUTHOR]

In this paper, we consider the inference for the component and system lifetime distribution of ak-unit parallel system with independent components based on system data. The components are assumed to have identical Weibull distribution. We obtain the maximum likelihood estimates of the unknown parameters based on system data. The Fisher information matrix has been derived. We propose β-expectation tolerance interval and β-content γ-level tolerance interval for the life distribution of the system. Performance of the estimators and tolerance intervals is investigated via simulation study. A simulated dataset is analyzed for illustration. [ABSTRACT FROM AUTHOR]

Bid-induced mitochondrial membrane permeabilization and cytochrome c release are central to apoptosis. It remains a mystery how tiny amounts of Bid synchronize the function of a large number of discrete organelles, particularly in mitochondria-rich cells. Looking at cell populations, the rate and lag time of the Bid-induced permeabilization are dose-dependent, but even very low doses lead eventually to complete cytochrome c release. By contrast. individual mitochondria display relatively rapid and uniform kinetics, indicating that the dose dependence seen in populations is due to a spreading of individual events in time. We report that Bid-induced permeabilization and cytochrome c release regularly demonstrate a wave-like pattern, propagating through a cell at a constant velocity without dissipation. Such waves do not depend on caspase activation or permeability transition pore opening. However, reactive oxygen species (ROS) scavengers suppressed the coordination of cytochrome c release and also inhibited Bidinduced cell death, whereas both superoxide and hydrogen peroxide sensitized mitochondria to Bid-induced permeabilization. Thus, Bid engages a ROS-dependent, local intermitochondrial potentiation mechanism that amplifies the apoptotic signal as a wave. [ABSTRACT FROM AUTHOR]

We report experimental implementation of a protocol for testing the Leggett-Garg inequality (LGI) for nuclear spins precessing in an external magnetic field. The implementation involves certain controlled operations, performed in parallel on pairs of spin-1/2 nuclei (target and probe) from molecules of a nuclear magnetic resonance ensemble, which enable evaluation of temporal correlations from an LG string. Our experiment demonstrates violation of the LGI for time intervals between successive mea- surements, over which the effects of relaxation on the quantum state of target spin are negligible. Further, it is observed that the temporal correlations decay, and the same target spin appears to display macro- realistic behavior consistent with LGI. [ABSTRACT FROM AUTHOR]

Abstract: First direct and quantitative study of singlet states using density matrix tomography is reported. A robust scheme for the tomography of a general density matrix of two spin 1/2 nuclei is introduced for this purpose. The study is carried out at different spin-lock conditions and the results are compared. [ABSTRACT FROM AUTHOR]

Summary: Calcium oscillations exert physiological control on mitochondrial energy metabolism and can also lead to mitochondrial membrane permeabilization and cell death. The outcome of the mitochondrial calcium signaling is altered by stress factors such as ceramide or staurosporine. However, the mechanism of this proapoptotic switch remains unclear. Using genetic, biochemical, pharmacological, and functional approaches, we here show that ceramide and staurosporine target PP2A and protein kinases A and C, respectively, in a mitochondria-associated signaling complex to induce dephosphorylation of the BH3-only protein Bad. Dephosphorylated Bad sensitizes the mitochondrial permeability transition pore (PTP) to Ca2+ through a Bcl-xL-sensitive and VDAC-mediated process. Furthermore, the Bad-induced sensitization of the PTP to Ca2+ does not require Bax or Bak. Thus, phospho-regulatory mechanisms converge on Bad to switch between the survival and apoptotic functions of mitochondrial calcium signaling by activating a mechanism whereby a BH3-only protein bypasses Bax/Bak and engages the PTP. [Copyright &y& Elsevier]

Abstract: Among the many unsolved problems of calcium signalling, the role of calcium elevations in apoptotic and necrotic cell death has been a focus of research in recent years. Evidence has been presented that calcium oscillations can effectively trigger apoptosis under certain conditions and that dysregulation of calcium signalling is a common cause of cell death. These effects are regularly mediated through calcium signal propagation to the mitochondria and the ensuing mitochondrial membrane permeabilization and release of pro-apoptotic factors from mitochondria to the cytoplasm. The progress in this area depended on the development of (1) fluorescent/luminescent probes, including fluorescent proteins that can be genetically targeted to different intracellular locations and (2) the digital imaging technology, fluorescence-activated cell sorting and fluorescent high throughput approaches, which allowed dynamic measurements of both [Ca2+] in the intracellular compartments of interest and the downstream processes. Fluorescence single cell imaging has been the only possible approach to resolve the cell-to-cell heterogeneity and the complex subcellular spatiotemporal organization of the cytoplasmic and mitochondrial calcium signals and downstream events. We outline here fluorometric and fluorescence imaging protocols that we set up for the study of calcium in the context of apoptosis. [Copyright &y& Elsevier]

Breast cancer, like most forms of cancer, is a fatal disease that claims more than half a million lives every year. In 2020, breast cancer overtook lung cancer as the most commonly diagnosed form of cancer. Though extremely deadly, the survival rate and longevity increase substantially with early detection and diagnosis. The treatment protocol also varies with the stage of breast cancer. Diagnosis is typically done using histopathological slides from which it is possible to determine whether the tissue is in the Ductal Carcinoma In Situ (DCIS) stage, in which the cancerous cells have not spread into the encompassing breast tissue, or in the Invasive Ductal Carcinoma (IDC) stage, wherein the cells have penetrated into the neighboring tissues. IDC detection is extremely time-consuming and challenging for physicians. Hence, this can be modeled as an image classification task where pattern recognition and machine learning can be used to aid doctors and medical practitioners in making such crucial decisions. In the present paper, we use an IDC Breast Cancer dataset that contains 277,524 images (with 78,786 IDC positive images and 198,738 IDC negative images) to classify the images into IDC(+) and IDC(-). To that end, we use feature extractors, including textural features, such as SIFT, SURF and ORB, and statistical features, such as Haralick texture features. These features are then combined to yield a dataset of 782 features. These features are ensembled by stacking using various Machine Learning classifiers, such as Random Forest, Extra Trees, XGBoost, AdaBoost, CatBoost and Multi Layer Perceptron followed by feature selection using Pearson Correlation Coefficient to yield a dataset with four features that are then used for classification. From our experimental results, we found that CatBoost yielded the highest accuracy (92.55%), which is at par with other state-of-the-art results—most of which employ Deep Learning architectures. The source code is available in the GitHub repository. [ABSTRACT FROM AUTHOR]

An enantioselective desymmetrization of prochiral 1,3-dinitropropanes has been developed which proceeds via enantiogroup differentiating organocatalytic allylic alkylation. Densely functionalized products with two vicinal stereocenters were obtained generally with good to excellent diastereoselectivity (up to >20: 1 dr) and superb enantioselectivity (up to >99: 1 er). [ABSTRACT FROM AUTHOR]

The hemispheric asymmetry of the solar-flare index during 1976 – 2018 from the Kandilli Observatory is studied in this investigation. The temporal duration covers Solar Cycles 21 – 23 and almost the whole of Solar Cycle 24. Different methodologies, such as cross-correlation analysis, rescaled-range analysis, empirical mode decomposition, and date-compensated discrete Fourier transform, have been used on the hemispheric solar-flare index as well as on absolute asymmetry data to study various inherent characteristics. We observed that: i) the temporal characteristics in the northern and southern hemispheres are different during the progression of a solar cycle; ii) the T-test indicates that Solar Cycles 21 and 23 do not have any dominant hemispheric effect, whereas Solar Cycle 22 and 24 have South-dominated hemispheric characteristics; iii) the southern hemisphere is leading by ten, three, and one months during Solar Cycles 21, 22, and 24, respectively, and for Solar Cycle 23 the hemispheres are in phase; iv) anti-persistence as well as short memory-dependent characteristics are present in both the hemispheric solar-flare index and the absolute asymmetry data; v) all of the time-series data have well-known periods of 11 years and 27 days as well as short-term periods around 7 days and 14 days. Apart from those, several mid-term periodicities such as the Rieger periodicity and quasi-biennial oscillations (QBOs) are also found in both hemispheric solar-flare index as well as absolute asymmetry index data; vi) the Waldmeier effect is also validated using solar-flare-index data. These results will enrich our knowledge about the distribution of hemispheric asymmetry in solar-flare-index data and may reveal some valuable points about asymmetry behaviors. [ABSTRACT FROM AUTHOR]