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This study elucidates the litter dynamics including decomposition rate both in-situ and ex-situ, the initial acquisition traits (LATs), morphological traits (LMTs) and production rate of leaf litter of four economically important tree species viz. Terminalia arjuna (TA), Tectona grandis (TG), Eucalyptus citriodora (EC) and Psidium guajava (PG) with the major objective of restoration of degraded urban ecosystems in dry tropics. Annual litterfall production rates were observed as: TG > TA > EC > PG. LMTs, that is, specific leaf area followed the trend: TG > TA > PG > EC, whereas leaf mass per area followed the reverse trend. In TA, LATs involving carbon (C), nitrogen (N) and cellulose were highest but C/N and lignin/N ratios were lowest, whereas lignin, polyphenol, C/N and lignin/N ratios were highest in PG. In the leaf litter bag experiment, the decomposition rate followed the trend: TA > TG > EC > PG. In-situ and ex-situ rates of decomposition of all the four leaf litters were found to be similar. LATs especially lignin/N, N and C/N ratios rather than LMTs were found to be a better predictor of the litter decomposition rate. TA plantation having a higher litter decomposition rate, may be recommended for inclusion in the restoration strategies of degraded urban land.
Understanding the effect of intricate surface wettability conditions on microswimmers is crucial for precisely navigating them across narrow microcirculatory networks. Here, we adopt the spherical squirmer model and Navier slip condition to delineate the microswimmer locomotion under a Poiseuille flow in a slit microchannel. Through a combined analytical–numerical approach utilizing bispherical coordinates and the superposition technique, we resolve the slip-modulated simultaneous hydrodynamic interaction with substrate boundaries. Phase portraits reveal that slip significantly alters propulsion mechanisms, destabilizing centreline stable oscillations of pullers beyond a threshold slip length. Superhydrophobic surfaces suppress near-wall rheotaxis states but preserve centreline focusing, facilitating slip-assisted directed transport without surface accumulation. Under strong background flows, subcritical Hopf bifurcation emerges for pullers at a critical slip length, transitioning dynamics from coexisting stable and unstable states to purely unstable behaviour. Contrastingly, for pushers, slip causes a transition from unstable to either stable or fixed-amplitude oscillations. Increased slip length reduces hydrodynamic repulsion on pullers from the walls by enhancing rotational velocity near the walls, whereas it counteracts the torque that causes unstable oscillations of pushers. Three-dimensional analysis of the trajectories reveals the significant role of the out-of-plane orientation of the microswimmer in its transitions between different swimming states. The presented regime maps offer parametric combinations for specific motion behaviours, guiding the development of smart microfluidic drug delivery systems and preventing biofilm deposition in biomedical devices.
One methodological approach to grasping a ‘big-picture’ history of modern science involves tracing the complex entanglements between scientific knowledge and the development of racism and racialized economic systems. Indeed, no historical account of any scientific field can be complete without acknowledging the role of race as an intellectual, social or economic factor. We substantiate this argument through a synthetic review of three overlapping threads in the historiography of science. First, historical research on ‘race science’ has analysed the formation of disciplines directly involved in constructing scientific concepts of race, including medicine, anthropology, linguistics, phrenology, psychology, archaeology and genetics. Second, historians have demonstrated that connections between race and science are not limited to the domain of race science. Rather, European imperial expansion, colonialism and capitalism created the foundational infrastructures undergirding the emergence of modern professional science. Finally, new research shows how race remains covertly embedded in theoretical frameworks, statistical formulae and technological devices still used by scientists today. Through these examples, we perceive a big-picture history of science in which its co-constitution with race links localized case studies and imperial narratives across space and time.
The molten sand that is a mixture of calcia, magnesia, alumina and silicate, known as CMAS, is characterized by its high viscosity, density and surface tension. The unique properties of CMAS make it a challenging material to deal with in high-temperature applications, requiring innovative solutions and materials to prevent its buildup and damage to critical equipment. Here, we use multiphase many-body dissipative particle dynamics simulations to study the wetting dynamics of highly viscous molten CMAS droplets. The simulations are performed in three dimensions, with varying initial droplet sizes and equilibrium contact angles. We propose a parametric ordinary differential equation (ODE) that captures the spreading radius behaviour of the CMAS droplets. The ODE parameters are then identified based on the physics-informed neural network (PINN) framework. Subsequently, the closed-form dependency of parameter values found by the PINN on the initial radii and contact angles are given using symbolic regression. Finally, we employ Bayesian PINNs (B-PINNs) to assess and quantify the uncertainty associated with the discovered parameters. In brief, this study provides insight into spreading dynamics of CMAS droplets by fusing simple parametric ODE modelling and state-of-the-art machine-learning techniques.
OBJECTIVES/GOALS: The primarygoal is to understand the challenges and barriers associated with the procurement of innovative technologies.Specifically, our research will answer the following question: what are the minimal requirements for a startup’s solution to beprocuredby anOntariohealthcare institution? METHODS/STUDY POPULATION: Participants will include procurement professionals at startups, healthcare institutions, and procurement facilitating agencies. Semi-structured interviews will be conducted in order to understand different procurement pathways and the possible procurement related gaps or barriers that startups face. Through qualitative ethnographic methods, participant interviews will characterize existing relationships and examine the rationale behind startup procurement decision-making. Data collection will include recordings, verbatim transcripts, and researcher field notes. Through inductive qualitative analysis, the data will be examined to build an intervention to assist in startup procurement. RESULTS/ANTICIPATED RESULTS: Our investigation will yield insight into expectations between hospital procurement requirements and startup procurement. The qualitative analysis will identify targets for engagement, and appropriate actors that can bridge gaps. Our results will identify pathways for procurement and the minimal procurement requirements to aid startup procurement planning. Our research will support innovators by delivering an intervention that will enable easier implementation of market ready solutions in a Canadian context. In line with principles from the National Center for Advancing Translational Sciences, this research can be used towards enhancing efficiency, speed of translation, and innovation. DISCUSSION/SIGNIFICANCE: We will contextualize the needs of start-ups and empower them to understand their procurement ecosystem. Facilitating better navigation of the procurement space allows for innovators to present solutions that healthcare organizations can adopt, resulting in improved clinical and patient outcomes.
The increasing demand for wireless communication has emphasized the need for multiband antennas. This study presents a novel design for a multiband antenna with reduced specific absorption rate (SAR), high gain, and improved front-to-back ratio (FBR) achieved through the integration with a 4 × 4 artificial magnetic conductor (AMC) surface. The proposed antenna covers a wide range of wireless frequency bands, including Industrial, Scientific, and Medical, Wireless Local Area Network, Worldwide Interoperability for Microwave Access, Wi-Fi 6E, and 7, with resonating frequencies at 2.4, 3.2, 5.5, 7.5, and 10 GHz. The AMC unit cell creates four zero-degree reflection phases with double negative properties at 2.5, 3.8, 5.5, and 7.5 GHz. The compact design measures 0.23λ0 × 0.296λ0 × 0.0128λ0 and placed 0.104λ0 above an AMC surface of size 0.512λ0 × 0.512λ0 × 0.1296λ0. This structure enhances the gain by up to 8.55dBi at 6.01 GHz. The proposed antenna has −10 dB impedance bandwidth for these corresponding frequencies viz 2.34–2.43 GHz (3.77%), 2.81–3.83 GHz (30.72%), 4.82–6.21 GHz (25.20%), 7–7.65 GHz (8.87%), and 8.06–10.31 GHz (24.5%). An overall average percentage reduction value of SAR taken at these frequencies has been found to be 96.11% with AMC structure. The antenna sample was successfully fabricated, and the experimental results have been found to match well with the simulation results. This integrated design offers a promising solution for wearable off-body communication devices.
Electrolyte solutions play an important role in energy storage devices, whose performance relies heavily on the electrokinetic processes at sub-micron scales. Although fluctuations and stochastic features become more critical at small scales, the long-range Coulomb interactions pose a particular challenge for both theoretical analysis and simulation of fluid systems with fluctuating hydrodynamic and electrostatic interactions. Here, we present a theoretical framework based on the Landau–Lifshitz theory to derive closed-form expressions for fluctuation correlations in electrolyte solutions, indicating significantly different decorrelation processes of ionic concentration fluctuations from hydrodynamic fluctuations, which provides insights for understanding transport phenomena of coupled fluctuating hydrodynamics and electrokinetics. Furthermore, we simulate fluctuating electrokinetic systems using both molecular dynamics (MD) with explicit ions and mesoscopic charged dissipative particle dynamics (cDPD) with semi-implicit ions, from which we identify that the spatial probability density functions of local charge density follow a gamma distribution at sub-nanometre scale (i.e. $0.3\,{\rm nm}$) and converge to a Gaussian distribution above nanometre scales (i.e. $1.55\,{\rm nm}$), indicating the existence of a lower limit of length scale for mesoscale models using Gaussian fluctuations. The temporal correlation functions of both hydrodynamic and electrokinetic fluctuations are computed from all-atom MD and mesoscale cDPD simulations, showing good agreement with the theoretical predictions based on the linearized fluctuating hydrodynamics theory.
Great. Thank you, Kate, and thanks to everybody for being here today. In January 2020, OutRight Action International and Human Rights Watch published a report called “Even if You Go to the Skies, We'll Find You,” regarding violence against LGBT people since the Taliban takeover in Afghanistan. What happened was in August of 2021 when the Taliban took over Afghanistan, there was an immediate reaction in terms of what was going to happen to LGBTQ people. I was finishing up my time at Human Rights Watch working in the LGBT Rights Program and was getting ready to transition to OutRight Action International.
A stroke is a potentially debilitating event which can render the victim unable to perform many tasks and functions, significantly decreasing their quality of life. This, in addition to emotional/mental changes post-stroke, can lead to a phenomenon known as “post stroke depression” (PSD), characterised by persistent low mood following a stroke.
Objectives
This study aims to amalgamate recommendations based on national guidelines and previous literature, in addition to an original inpatient study of stroke patients within a hospital, to construct a standardised protocol of the management of PSD in the hospital setting.
Methods
248 patients who had been treated for stroke within a hospital were analysed using hospital notes to assess for incidence of PSD, in-hospital management, and outpatient follow-up. In addition a literature search was conducted and national guidelines were consulted to develop a PSD management protocol.
Figure 1: Post stroke depression management protocol.
Results
While 8% (20/248) of stroke patients experienced low mood immediately post stroke, 45% (9/20) of these patients did not receive any therapy or drug treatment, 80% (16/20) did not receive any outpatient monitoring of their mood and 100% of patients received no outpatient monitoring of newly commenced antidepressants.
Conclusions
Using the results and literature search, a PSD management protocol, encompassing both appropriate in-hospital therapy and robust outpatient monitoring, was developed (Figure 1). We hope that through this, hospital care of PSD can be improved and optimised, in order for victims of PSD to receive the best possible, evidence-based care available to treat this potentially devastating condition.
The newer cancer treatment technologies hold the potential of providing improved health outcomes at an additional cost. So it becomes obligatory to assess the costs and benefits of a new technology, before defining its clinical value. We assessed the cost-effectiveness of intensity-modulated radiotherapy (IMRT) as compared to 2-dimensional radiotherapy (2-DRT) and 3-dimensional radiotherapy (3D-CRT) for treating head and neck cancers (HNC) in India. The cost-effectiveness of 3-DCRT as compared to 2-DRT was also estimated.
Methods
A probabilistic Markov model was designed. Using a disaggregated societal perspective, lifetime study horizon and 3 percent discount rate, future costs and health outcomes were compared for a cohort of 1000 patients treated with any of the three radiation techniques. Data on health system cost, out of pocket expenditure, and quality of life was assessed through primary data collected from a large tertiary care public sector hospital in India. Data on xerostomia rates following each of the radiation techniques was extracted from the existing randomized controlled trials.
Results
IMRT incurs an incremental cost of $7,072 (2,932–13,258) and $5,164 (463–10,954) per quality-adjusted life year (QALY) gained compared to 2-DRT and 3D-CRT, respectively. Further, 3D-CRT as compared to 2-DRT requires an incremental cost of $8,946 (1,996–19,313) per QALY gained.
Conclusion
Both IMRT and 3D-CRT are not cost-effective at 1 times GDP per capita for treating HNC in India. The costs and benefits of using IMRT for other potential indications (e.g. prostate, lung) require to be assessed before considering its introduction in India.
Gas turbine engines for fixed-wing or rotary-wing aircraft are operated in a variety of harsh weather environments ranging from arctic, volcanic zones, to desert conditions. Operation under these degraded conditions leads to the undesired entrainment of complex particulates resulting in drastic performance losses. Hence, there is a critical need to understand the governing mechanisms to inform the development of durable thermal and environmental barrier coatings. The objective of the current work is to present a novel multiscale physics-based approach to study two-phase flows that take into account the underpinning particle transport and deposition dynamics. Sessile droplet models are presented and used to compute the contact angle at high temperatures and compared with experiments. The study also investigates the sensitivity of deposition patterns to the Stokes number and the results identify local vulnerability regions. The analysis suggests that particle size distributions and the initial trajectories of the particles are critically important in predicting the final deposition pattern.
The mitigation of CMAS (calcium–magnesium–aluminum–silicon oxide) infiltration is a major requirement for the stability of thermal barrier coatings. In this study, yttria-stabilized zirconia (YSZ)–Al2O3–SiC, YSZ–Al2O3–Ta2O5, and YSZ–Al2O3–Nb2O5 self-healing composites produced by uniaxially pressing powders were investigated as an alternative to YSZ. CMAS infiltration in these materials was tested at 1250 °C for 10 h. Comparing the depth of CMAS infiltration using scanning electron microscope (SEM) in tandem with electron-dispersive X-ray spectroscopy (EDS), all self-healing materials were found to perform better than the reference materials. While standard YSZ shows massive CMAS infiltration, SEM micrographs and EDS maps revealed a 33-fold improvement in CMAS resistance for the YSZ–Al2O3–Nb2O5 system, which exhibited the best performance among the selected self-repairing materials. X-ray diffraction and high-resolution SEM micrographs taken 10 μm below the surface revealed that CMAS only infiltrated pores in the topmost region of the samples. Both YSZ–Al2O3–Ta2O5 and YSZ–Al2O3–Nb2O5 systems showed no signs of chemical reaction with CMAS.
The objective of this work is to computationally investigate the impact of an incidence-tolerant rotor blade concept on gas turbine engine performance under off-design conditions. When a gas turbine operates at an off-design condition such as hover flight or takeoff, large-scale flow separation can occur around turbine blades, which causes performance degradation, excessive noise, and critical loss of operability. To alleviate this shortcoming, a novel concept which articulates the rotating turbine blades simultaneous with the stator vanes is explored. We use a finite-element-based moving-domain computational fluid dynamics (CFD) framework to model a single high-pressure turbine stage. The rotor speeds investigated range from 100% down to 50% of the designed condition of 44,700 rpm. This study explores the limits of rotor blade articulation angles and determines the maximal performance benefits in terms of turbine output power and adiabatic efficiency. The results show articulating rotor blades can achieve an efficiency gain of 10% at off-design conditions thereby providing critical leap-ahead design capabilities for the U.S. Army Future Vertical Lift (FVL) program.
Military operations occurring in particle-laden environments have resulted in aircraft incidents and loss of life due to sand ingestion into the engine. Sand melts in the hot combustion environment and deposits as glassy calcia–magnesia–alumino–silicates (CMAS) which leads to rapid performance degradation due to clogged air pathways in the engine. A novel, composite thermal barrier coating (TBC) consisting of yttria-stabilized zirconia (YSZ) blended with gadolinia is proposed that combines the excellent thermo-mechanical properties of YSZ together with the CMAS resistance of rare-earth oxides. YSZ was blended with 2, 8, 17, and 32 vol% gadolinia and tested under simulated engine-relevant conditions. The presence of gadolinia in the composite coating reduced the adhesion of the CMAS, and at 32 vol% gadolinia addition, the CMAS was completely delaminated. A possible CMAS adhesion mitigating mechanism is discussed. This work demonstrated the capability of a new composite TBC to significantly reduce CMAS adhesion.
Since the 1970s, belief in the importance of participatory empowerment has been constantly asserted through various mass-inclusive developmental strategies. The growing interest in theatre for generating socio-political capacity-building among people gave rise to the Theatre of the Oppressed, conceptualized and developed by Augusto Boal. This article provides a brief outline of the modus operandi of Boal’s practice, and focuses on investigating the theoretical and practical methodology of Jana Sanskriti, the West Bengal group of practitioners of Theatre of the Oppressed. The article investigates the dialogical relationship between actors and audience in the three phases of the group’s theatre-making process: pre-performance; during the performance; and after it. It proposes an illustrative model of Jana Sanskriti’s dialogical approach towards experiencing a developmental surge in society. Shubhra Ghoshal is a research scholar at the Department of Humanities and Social Sciences at the Indian Institute of Technology (Indian School of Mines) in Dhanbad, India. Nirban Manna is an Assistant Professor at the Department of Humanities and Social Sciences, Indian Institute of Technology (Indian School of Mines) in Dhanbad.
The flexible motion of the inchworm makes the locomotion mechanism as the prominent one than other limbless animals. Recently, the application of engineering greatly assists the inchworm locomotion to be applicable in the robotic mechanism. Due to the outstanding robustness, sliding mode control (SMC) has been validated as a robust control strategy for diverse types of systems. Even though the SMC techniques have made numerous achievements in several fields, some systems cannot be comfortably accepted as the general SMC approaches. Accordingly, this paper develops the Grey Wolf-Second order sliding mode control (GW-SoSMC) to control the manipulator of the inchworm robot. The GW-SoSMC reduces the chattering phenomenon of SMC and improves the controlling ability of SoSMC by weightage function. Subsequently, it compares the performance of the proposed method with several conventional techniques like Grey Wolf-SMC (GW-SMC), FireFly-SoSMC (FF-SoSMC), Artificial Bee Colony-SoSMC (ABC-SoSMC), Group Searching-SoSMC (GS-SoSMC), and Genetic Algorithm-SoSMC (GA-SoSMC). It portrays the valuable comparative analysis by measuring the accomplished joint angles, error, and response of the controller. Thus the proposed method discovers the supervisory controller for the inchworm robot that is immensely better than conventional controllers mentioned earlier.
To examine the relationship between unit-wide Clostridium difficile infection (CDI) susceptibility and inpatient mobility and to create contagion centrality as a new predictive measure of CDI.
Design:
Retrospective cohort study.
Methods:
A mobility network was constructed using 2 years of patient electronic health record data for a 739-bed hospital (n = 72,636 admissions). Network centrality measures were calculated for each hospital unit (node) providing clinical context for each in terms of patient transfers between units (ie, edges). Daily unit-wide CDI susceptibility scores were calculated using logistic regression and were compared to network centrality measures to determine the relationship between unit CDI susceptibility and patient mobility.
Results:
Closeness centrality was a statistically significant measure associated with unit susceptibility (P < .05), highlighting the importance of incoming patient mobility in CDI prevention at the unit level. Contagion centrality (CC) was calculated using inpatient transfer rates, unit-wide susceptibility of CDI, and current hospital CDI infections. The contagion centrality measure was statistically significant (P < .05) with our outcome of hospital-onset CDI cases, and it captured the additional opportunities for transmission associated with inpatient transfers. We have used this analysis to create easily interpretable clinical tools showing this relationship as well as the risk of hospital-onset CDI in real time, and these tools can be implemented in hospital EHR systems.
Conclusions:
Quantifying and visualizing the combination of inpatient transfers, unit-wide risk, and current infections help identify hospital units at risk of developing a CDI outbreak and, thus, provide clinicians and infection prevention staff with advanced warning and specific location data to inform prevention efforts.