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Background: Understanding the conceptual models that underpin interventions, and the linkage between mechanisms of action and their intended outcomes, makes replication possible. Aim: To identify and appraise conceptual models and mechanisms of action underpinning end-of-life care interventions to improve spiritual well-being. Design: A systematic review following the Preferred Reporting Items for Systematic Review and Meta-Analysis was conducted. Data sources: A comprehensive search was performed in eight databases from inception to January 12, 2021. Results: A logic model was developed and potential mechanisms of action were identified from the seven included studies. Conclusion: First, conceptual models that have relevance and appropriateness to cultural setting are required to underpin future intervention development and implementation. Second, careful intervention development should articulate the link between concept, mechanisms, and outcomes. Third, selection of valid outcome measured must have a strong justification of how the construct being measured relates to the intervention goals. [ABSTRACT FROM AUTHOR]

New paradigm shifts and 6G technological rev-olution in vehicular services have emerged toward unmanned driving, automated transportation, and self-driving vehicles. As the technology for autonomous cars becomes mature, real challeng-es come from reliable, safe, real-time connected transportation operations to achieve ubiquitous and prompt information exchanges with massive connected and autonomous vehicles. This article introduces novel wireless distributed architectures that embed the edge computing capability inside software-defined vehicular networking infrastructure. Such edge networks consist of open-loop grant-free communications and computing-based control frameworks, which enable dynamic eco-routing with ultra-low latency and mobile data-driven orchestration. Thus, this work advanc-es the frontiers of machine learning potential and next-generation mobile systems in vehicular net-working applications. [ABSTRACT FROM AUTHOR]

Achievable data rates in wireless systems rely heavily on the available channel state information (CSI) throughout the network. However, feedback links, which provide this information, are scarce, unreliable, and subject to security threats. In this work, we study the impact of having intermittent feedback links on the capacity region of the canonical two-user erasure broadcast channels. In our model, at any time instant, each receiver broadcasts its CSI, and at any other node, this information either becomes available with unit delay or gets erased. For this setting, we develop a new set of outer bounds to capture the intermittent nature of the feedback links. These outer bounds depend on the probability that the CSI from both receivers are erased at the transmitter. In particular, if at any time, the CSI from at least one of the two receivers is available at the other two nodes, then the outer-bounds match the capacity with global delayed CSI. We also provide capacity-achieving transmission strategies under certain scenarios, and we establish a connection between this problem and Blind Index Coding with feedback. [ABSTRACT FROM AUTHOR]

We characterize the capacity region of the two-user broadcast packet erasure channel (PEC) with single-user delayed channel state information (CSI). More precisely, we assume one receiver does not provide its channel state to the other two nodes (the other receiver and the transmitter), while the other receiver reveals its state globally with unit delay. This is a hybrid CSI at the transmitter (CSIT) setting where the transmitter has the delayed CSI of one user but not the other. Previous results developed opportunistic network coding schemes for this setting, which strictly enlarge the achievable rate region compared to the no-CSIT baseline. Characterization of the capacity region with single-user delayed CSI, however, remained open. In this work, we develop an improved achievability strategy and show that the capacity region, surprisingly, matches that of the broadcast PEC with global delayed CSI of both users. The key to such improvement over previous results is a new precoding strategy for the retransmission phase of the opportunistic network coding scheme. It harnesses the single-user delayed CSI in the retransmission phase, so that interference from the feedback receiver can be aligned at the other receiver. Besides the broadcast PEC with two private messages, an extension to a model with an additional common message is also provided and the corresponding capacity region with single-user CSI also matches that with global delayed CSI. Finally, further extensions to three-user cases are also provided. [ABSTRACT FROM AUTHOR]

• Four TADF materials with carbazole donor, and benzonitrile-substituted pyrimidine or triazine as acceptor core were developed. • OLEDs with m-CzPym, p-CzPym, m-CzTrz, and p-CzTrz as host and 4CzIPN were fabricated. • An impressive external quantum efficiency of 31.5% and a superior power efficiency of 116.5 lm W−1 were achieved. • Impressive efficiency roll-off performance (approximately 90% of EQE max at 5000 cd m−2). Four bipolar molecules, namely m-CzPym , p-CzPym , m-CzTrz , and p-CzTrz , with carbazole (Cz) donor and a benzonitrile-substituted pyrimidine (Pym) or triazine (Trz) acceptor core were synthesized and characterized. The electron deficiency of heteroaryl cores together with the substitution pattern of benzonitrile were employed to tune the energy levels as well as the thermally activated delayed fluorescence (TADF) characteristics. The four molecules exhibited TADF behavior with inferior photoluminescent quantum yields (PLQYs) that limit their applications as emitters. These bipolar molecules were employed as TADF host materials for the benchmark TADF emitter 4CzIPN to achieve high-performing green TADF organic light-emitting diodes (OLEDs). Among the molecules, m-CzPym -hosted TADF-OLEDs achieved a maximum external quantum efficiency (EQE max) of 31.5%, maximum power efficiency (PE max) of 95.6 lm/W, and maximum current efficiency (CE max) of 100.2 cd/A. Notably, p-CzPym -hosted TADF-OLEDs also achieved a PE max of 116.5 lm/W, turn-on voltage of 2.5 V, and impressive low efficiency roll-off performance (>89% of EQE max at 5000 cd/m2), representing one of the highest efficiencies ever reported in 4CzIPN-doped devices. The high device efficiency can be ascribed to the balanced ambipolar carrier-transporting character of the host materials and high PLQY as well as the outstanding light outcoupling efficiency of the emitting layer. [ABSTRACT FROM AUTHOR]

Streaming codes take a string of source symbols as input and output a string of coded symbols in real time, which eliminate the queueing delay of traditional block codes and are thus especially appealing for delay sensitive applications. Existing works on streaming code performance either focused on the asymptotic error-exponent analyses, or on the optimal code construction under deterministic adversarial channel models. In contrast, this work analyzes the exact error probability of random linear streaming codes (RLSCs) in the large field size regime over the stochastic i.i.d. symbol erasure channel model. A closed-form expression of the error probability of large-field-size RLSCs is derived under, simultaneously, the finite memory length and decoding deadline constraints. The result is then used to examine the intricate tradeoff between memory length (complexity), decoding deadline (delay), code rate (throughput), and error probability (reliability). Numerical evaluation shows that under the same code rate and error probability requirements, the end-to-end delay of RLSCs is 40–48% of that of the optimal block codes (i.e., MDS codes). This implies that switching from block codes to streaming codes not only eliminates the queueing delay completely (which accounts for the initial 50% of the delay reduction) but also improves the reliability (which accounts for the additional 2–10% delay reduction). [ABSTRACT FROM AUTHOR]

Careful hematologic management is required in surgical patients with traumatic acute subdural hematoma (aSDH) taking antithrombotic medications. We sought to compare outcomes between patients with aSDH taking antithrombotic medications at admission who received antithrombotic reversal with patients with aSDH not taking antithrombotics. Retrospective review identified patients with traumatic aSDH requiring surgical evacuation. The cohort was divided based on antithrombotic use and whether pharmacologic reversal agents or platelet transfusions were administered. A 3-way comparison of outcomes was performed between patients taking anticoagulants who received pharmacologic reversal, patients taking antiplatelets who received platelet transfusion, and patients not taking antithrombotics. Multivariable regressions, adjusted for injury severity, further investigated associations with outcomes. Of 138 patients who met inclusion criteria, 13.0% (n = 18) reported taking anticoagulants, 16.7% (n = 23) reported taking antiplatelets, and 3.6% (n = 5) reported taking both. Patients taking antiplatelets who received platelet transfusion had longer intraoperative times (P = 0.040) and higher rates of palliative care consultations (P = 0.046) compared with patients taking anticoagulants who received pharmacologic reversal and patients not taking antithrombotics. Across groups, no significant differences were found in frequency of in-hospital intracranial hemorrhage and venous thromboembolism, length of hospital stay, rate of inpatient mortality, or follow-up health status. In multivariable analysis, intraoperative time remained longest for the antiplatelets with platelet transfusion group. Other outcomes were not associated with patient group. Among surgical patients with traumatic aSDH, those taking antiplatelet medications who receive platelet transfusions experience longer intraoperative procedure times and higher rates of palliative care consultation. Comparable outcomes were observed between patients receiving antithrombotic reversal and patients not taking antithrombotics. [ABSTRACT FROM AUTHOR]

The Byzantine distributed quickest change detection (BDQCD) is studied, where a fusion center monitors the occurrence of an abrupt event through a bunch of distributed sensors that may be compromised. We first consider the binary hypothesis case where there is only one post-change hypothesis and prove a novel converse to the first-order asymptotic detection delay in the large mean time to a false alarm regime. This converse is tight in that it coincides with the currently best achievability shown by Fellouris et al.; hence, the optimal asymptotic performance of binary BDQCD is characterized. An important implication of this result is that, even with compromised sensors, a 1-bit link between each sensor and the fusion center suffices to achieve asymptotic optimality. To accommodate multiple post-change hypotheses, we then formulate the multi-hypothesis BDQCD problem and again investigate the optimal first-order performance under different bandwidth constraints. A converse is first obtained by extending our converse from binary to multi-hypothesis BDQCD. Two families of stopping rules, namely the simultaneous d-th alarm and the multi-shot d-th alarm, are then proposed. Under sufficient link bandwidth, the simultaneous d-th alarm, with d being set to the number of honest sensors, can achieve the asymptotic performance that coincides with the derived converse bound; hence, the asymptotically optimal performance of multi-hypothesis BDQCD is again characterized. Moreover, although being shown to be asymptotically optimal only for some special cases, the multi-shot d-th alarm is much more bandwidth-efficient and energy-efficient than the simultaneous d-th alarm. Built upon the above success in characterizing the asymptotic optimality of the BDQCD, a corresponding leader-follower Stackelberg game is formulated and its solution is found. [ABSTRACT FROM AUTHOR]