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This article presents the effect of aluminium nitride (AlN) epilayer (EPL) growth rate on the growth of semipolar (11–22) InGaN/GaN light emitting diode (LED). Three samples are grown with different AlN EPL growth rates, which are low (L1, 1.0 nm s−1), intermediate (L2, 1.3 nm s−1), and high (L3, 1.6 nm s−1) growth rate. The root‐mean‐square (RMS) and peak‐to‐valley roughness show an increasing trend with the increasing AlN EPL growth rate which is attributed to an increment in indium composition as justified by the photoluminescence results. The sample with AlN EPL growth rate of 1.3 nm s−1 (L2) exhibits an outstanding crystal quality in terms of defect densities reduction, with a minimum basal stacking fault density of 1.60 × 104 cm−1 as calculated. Besides that, the obvious fringes of InGaN/GaN peaks observed in 2θ−ω scan proves that a high abruptness multi‐quantum well is attained. Sample L2 also shows a single peak profile in both photoluminescence and electroluminescence spectra with green wavelength emission of 506 and 537 nm, respectively, indicating a homogeneous indium composition. As the injection current is swept from 5 to 40 mA for sample L2, a weak blueshift of ≈6 nm is observed which indicates a reduction in quantum‐confined Stark effect (QCSE). [ABSTRACT FROM AUTHOR]

Findings from brain imaging studies investigating the neural underpinnings of antisocial behavior have implicated the prefrontal cortex in the regulation of aggressive reactions. However, relatively few studies have examined the role of the prefrontal cortex on aggression in an experimental way. This study examines whether upregulating the prefrontal cortex using repeated transcranial direct current stimulation (tDCS) reduces aggressive behavior. In a double-blind, parallel-group, randomized controlled trial, 88 healthy adults (42 males, 46 females) were assigned to one session of anodal tDCS over the ventromedial prefrontal cortex (n = 47) or sham stimulation (n = 41) per day for three consecutive days and assessed using a behavioral measure of aggression. Levels of aggressive responses post-intervention did not significantly differ between the active and sham stimulation groups. However, a significant interaction effect between the stimulation group and gender was observed, whereby males, but not females, exhibited reduced aggression after prefrontal stimulation. To the authors' knowledge, this is the first study to examine the effect of multi-session prefrontal tDCS on aggressive behavior in healthy adults. Results highlight that there are differences in responsivity to tDCS in modifying aggressive behavior. [ABSTRACT FROM AUTHOR]

Radiomics using rectal MRI radiomics has emerged as a promising approach in predicting pathological complete response. In this study, we present a typical pipeline of a radiomics analysis and review recent studies, exploring applications, development of radiomics methodologies and model construction in pCR prediction. Finally, we will offer our opinion about the future and discuss the next steps of rectal MRI radiomics for predicting pCR. [Display omitted] • Several studies have shown promising results using radiomics to predict pathological response to rectal cancer. • Different methods were used to build the prediction models and very few studies did external validation. • Studies evaluated radiomics including pre-treatment MRI, post-treatment MRI, a combination of them, or delta-radiomics. • The studies with better performance included radiomics and qualitative variables from MR in the prediction model. [ABSTRACT FROM AUTHOR]

Much progress has recently been made to enhance mesoscopic traffic simulation with the focus on advanced modeling features and traffic management support capabilities. Subsequently, the computational performance needs to be improved in order to make mesoscopic traffic simulation stay effective to real-time applications. This paper presents a framework for mesoscopic traffic simulation which offloads both the demand and supply components to GPU. The simulation algorithm divides the simulation flow into different steps and designs multiple kernels to handle the steps. A high level of data parallelism is achieved by assigning the GPU threads to the appropriate components of the traffic network. Several optimization options using an innovative data structure and improved warp execution are also deployed to harness the GPU performance while preserving simulation correctness. The performance of the framework is evaluated in a real network showing the speedup of up to nearly 5 times in the demand simulation and more than 4 times in the supply simulation compared to the sequential simulation. [ABSTRACT FROM AUTHOR]

• The performance of InGaN/GaN LED is governed by the ammonia partial pressures. • Under low V/III ratio growth condition, InGaN QW behaves differently with GaN QB. • Threshold value of ∼ 300 Pa observed for the InGaN QW growth. • Above threshold value, InGaN growth rate increases with In incorporation and vice versa. • High roughness at high ammonia partial pressure allows higher indium incorporation. This paper presents the effect of ammonia partial pressure at a relatively low fixed V/III (∼765) growth atmosphere on the growth of multi-quantum well (MQW) structures and the light emitting diode (LED) emission wavelength. At fixed V/III ratio, ammonia partial pressure together with the consequent group III partial pressures are shown to influence the growth of InGaN/GaN MQWs in term of growth rate and the indium incorporation for the quantum well. It is also observed that the growth of InGaN quantum well (QW) behaves differently as compared to GaN quantum barrier (QB) at low V/III ambient. For the growth of InGaN QW, the data collected shows the existence of threshold point for ammonia partial pressure of ∼300 Pa. In the regime below the threshold value, the decomposition of InGaN due to severe dissociation of In-N bonds caused the growth rate to be extremely low. As the ammonia partial pressure increases above the threshold value, the growth rate of InGaN QW increases sharply together with an improvement in indium incorporation, as proven by the XRD and (11–24) asymmetric reciprocal space mapping (RSM) results. The XRD result is consistent with the atomic force microscopy (AFM) results. As the partial pressures increases, the RMS and peak-to-valley roughness increases which is credited to the increment in indium incorporation. Furthermore, "needle-like" structures can be observed over all samples when the MQWs were grown with limited ammonia partial pressure. During the growth for the LED structure with thin layers of InGaN/GaN, the partial pressure of ammonia became a dominating factor in the formation of well-abrupt layer interfaces. Through the XRD and room-temperature photoluminescence (RTPL) results, it is shown that abrupt layers can be formed at higher ammonia partial pressures, while indium clusters tend to form at a lower partial pressure, which are most probably due to the insufficient N concentration, while the electroluminescence (EL) results were consistent as well. Therefore, it is once again confirmed that the performance of the InGaN/GaN LED is highly governed by the partial pressures of the ammonia. [ABSTRACT FROM AUTHOR]

Hepatic capsular retraction refers to the loss of the normal convex hepatic contour, with the formation of an area of flattening or concavity. This can result from myriad causes, including intrinsic hepatic conditions such as cirrhosis, biliary obstruction, benign tumours, malignancy and infections, as well as extrahepatic causes such as trauma. This article aims to provide familiarity with this wide spectrum of conditions, including mimics of hepatic capsular retraction, by highlighting the anatomic, pathologic and imaging features that help distinguish these entities from one another. Teaching Points : • Hepatic capsular retraction can occur due to various intrinsic or extrinsic hepatic causes. • Hepatic capsular retraction is observed in both benign and malignant conditions. • Recognising associated imaging features can help elicit causes of hepatic capsular retraction. [ABSTRACT FROM AUTHOR]

Introduction: Adrenal hemorrhage is an uncommon but potentially life-threatening condition, particularly in cases of bilateral adrenal hemorrhage causing primary adrenal insufficiency. It is difficult to diagnose clinically, particularly in critically ill patients, given its non-specific symptoms and signs, which include abdominal pain, vomiting, fever, weakness, hypotension, and altered conscious state. Non-traumatic adrenal hemorrhage has been observed to occur in times of physiological stress, such as post-surgery, sepsis, burns, and hypotension. This is hypothesized to be due to a combination of increased arterial blood flow to the adrenal glands, the paucity of draining adrenal venules and adrenal vein thrombosis, leading to intra-glandular vascular congestion and subsequent hemorrhage. Case series: We present four cases of non-traumatic adrenal hemorrhage, which demonstrated features of preceding adrenal congestion (adrenal gland thickening and peri-adrenal fat stranding) on computed tomography (CT) imaging. Comparison was made with 12 randomly selected intensive care patients to observe if these findings were prevalent in this subgroup of patients. Conclusion: Non-traumatic adrenal hemorrhage is an uncommon condition that is difficult to diagnose clinically. As such, it may be useful to recognize CT features of adrenal congestion as a sign for potential adrenal dysfunction and subsequent adrenal hemorrhage, so early steroid replacement therapy can be commenced to prevent death from adrenal insufficiency. [ABSTRACT FROM AUTHOR]

Considerable work has been done on student evaluation of teaching/teachers, but reservations remain about its use for summative purposes. Student ratings are not universally accepted as being reliable, nor can they provide really meaningful information. Qualitative comments can provide a better understanding but they tend not to be user-friendly from lack of structure and connectedness. This study attempts to devise a method for ‘quantifying’ students’ comments to increase their usefulness in complementing/confirming ratings. The quantified results enable the profile construction of what students regard as an effective/ineffective teacher, and enable identification of strengths and weaknesses. Our findings counter some commonly held assumptions, including those which held that high ratings are dependent on small class size and ‘dumbing down’ of courses and the consequent expectation of high grades. The findings also indicate that students value teaching quality more than teacher characteristics, suggesting their ability to make valid judgments about teaching effectiveness. [ABSTRACT FROM AUTHOR]

Opinion exchange is useful when a military agent needs to take the opinions of others into account before decision making. Few studies have addressed opinion dynamics in military command and control (C2) organizations, which are often hierarchically ranked in a tree structure. Moreover, military agents should have different tolerance levels when communicating with differentially ranked agents, which is our reasoning for proposing an opinion dynamics model with multi-level tolerance in this study. We can use this model to test opinion dynamics models in depth and further analyze and compare them to traditional tree organizations and other organization forms, including small-world and scale-free networks. Opinion dynamics experiments show that although traditional indices such as a clustering coefficient or the average distance of a small-world network are worse than those of a scale-free network, opinion dynamics indices, which include the number of rounds to fixed opinions, number of opinion clusters, and relative size of the largest small-world cluster are unexpectedly better than those of a scale-free network. Moreover, adding links to a tree network can enhance the tendency to consensus, while a small-world network needs fewer links compared to a scale-free network. [ABSTRACT FROM AUTHOR]

A perennial simulation framework is proposed within the domain of crisis management simulation. Motivated by a need for establishing information superiority through decision-support analysis, the framework is designed to use symbiotic simulation and is also suitable for the hindsight and foresight studies that drive crisis-related preparedness exercises. The framework provides a novel feature of incorporating Human in the Loop simulations using virtual reality as a part of the symbiotic simulation. We coin the term perennial simulation to refer to our framework being enduring (the simulation working symbiotically with the real system), and recurring (performing “what-if?” simulations and continually providing feedback to the real system). Three case studies examine the application of the framework to crisis-related scenarios. The framework is shown to be useful and capable of dealing with crisis situations and adding value to existing expert advice, forming a symbiotic feedback loop that aids crisis management. [ABSTRACT FROM AUTHOR]

Mesoscopic traffic simulation is a promising technology for handling large-scale dynamic traffic assignment problems. Meanwhile, GPU has been a research hotspot in the last decade because of its massive parallel performance compared with CPU. Although several works deal with GPU-based parallel performance, few have addressed the issue of real-world network applications. Thus, the performance of GPU on realistic road networks is still not clear. In this paper, an ideal grid network and a realistic Singapore expressway network are implemented and compared. The former gets a speedup of 10.00 while the latter only get a speedup of 2.37. The two main reasons for this lower efficiency of a real network are the more complex data structure caused by network topology and fewer numbers of threads due to the scale of the expressway network. Future works need more effort to develop a system with better data structure and better designed concurrent threads. [ABSTRACT FROM AUTHOR]

Objective: The objective was to demonstrate that percutaneous nephrolithotomy (PCNL) can be safely performed with a tubeless or totally tubeless drainage technique. Introduction: Standard PCNL includes nephrostomy tube placement designed to drain the kidney and operative tract at the conclusion of the procedure. Modern technique trend is tubeless PCNL and totally tubeless PCNL, which are performed without standard nephrostomy drainage. We aim to reinforce current literature in demonstrating that PCNL can be safely performed using a tubeless technique. With compounded supportive data, we can help generate a trend toward a more cost-effective procedure with improved pain profiles and patient satisfaction, as previously shown with the tubeless technique. Methods: Retrospective analysis of 165 patients who underwent PCNL treatment was performed. Of this group, 127 patients underwent traditional nephrostomy drainage following PCNL. A tubeless procedure was performed in the remaining 38 patients. Patient's postoperative stone size and burden as well as complication profiles were analyzed. Largest stone size and total stone burden was similar between the groups. Results: Patient characteristics and demographic information were compared and no significant statistical difference was identified between the groups. Complication rates between the groups were compared and no statistical difference was noted. A total of 23 patients had at least one postoperative complication. Conclusion: Tubeless and totally tubeless PCNL demonstrates equivalent outcomes in the properly selected patient group when compared to PCNL performed with a nephrostomy tube. Although this is not the first study to demonstrate this, a large majority of urologists continue standard nephrostomy placement after PCNL. More studies are needed that demonstrate safety of this practice to shift the pendulum of care. Thus, tubeless and totally tubeless PCNL can be performed safely and effectively, which has previously been shown to improve cost, patient pain profiles, and length of hospitalization. [ABSTRACT FROM AUTHOR]