Abstract
The kinematics and dynamics of stellar and substellar populations within young, still-forming clusters provide valuable information for constraining theories of formation mechanisms. Using ...Keck II NIRSPEC+AO data, we have measured radial velocities for 56 low-mass sources within 4′ of the core of the Orion Nebula Cluster (ONC). We also remeasure radial velocities for 172 sources observed with SDSS/APOGEE. These data are combined with proper motions measured using HST ACS/WFPC2/WFC3IR and Keck II NIRC2, creating a sample of 135 sources with all three velocity components. The velocities measured are consistent with a normal distribution in all three components. We measure intrinsic velocity dispersions of (
σ
v
α
,
σ
v
δ
,
σ
v
r
) = (1.64 ± 0.12, 2.03 ± 0.13,
2.56
−
0.17
+
0.16
) km s
−1
. Our computed intrinsic velocity dispersion profiles are consistent with the dynamical equilibrium models from Da Rio et al. (2014) in the tangential direction but not in the line-of-sight direction, possibly indicating that the core of the ONC is not yet virialized, and may require a nonspherical potential to explain the observed velocity dispersion profiles. We also observe a slight elongation along the north–south direction following the filament, which has been well studied in previous literature, and an elongation in the line-of-sight to tangential velocity direction. These 3D kinematics will help in the development of realistic models of the formation and early evolution of massive clusters.
Display omitted
•Basic mechanisms and applications of hydrogels for water and energy generation.•Advanced optimization strategies to improve water and energy production efficiency.•The integration of ...infrastructure with water and energy multifunctional systems.•Challenges and future directions for sustainable water-energy generation systems.
Hydrogels are emerging as an ideal platform for sustainable water and energy nexuses due to their low-cost, ease of processing, versatile functions, unique structural networks, and high adaptability. The establishment of a solar-thermal-electricity system assumes critical importance in achieving effective solar energy utilization. This review focuses on recent advances in hydrogel-enabled solar steam generation (SGG) and atmospheric water harvesting (AWH) systems and discuss their extended applications for renewable energy, such as thermal-electricity and green hydrogen generation. Furthermore, advanced material development and various engineering strategies are proposed to enhance water and energy generation efficiency, taking into account the fundamental structure–property-application relationships (SPAR). Finally, research challenges and future opportunities for fundamental studies and industrial implementation of hydrogel-based freshwater and renewable energy generation systems are put forward.
Objective
This study aims to compare the outcomes of higher calorie refeeding (HCR) and a lower calorie refeeding (LCR) methods among a diverse sample of young Asian adolescents admitted to a ...tertiary institution in Asia for management of anorexia nervosa (AN).
Method
This is a retrospective case control study of Asian adolescents who were managed using an inpatient HCR protocol (2016–2017) and an LCR protocol (2010–2014). Baseline characteristics, daily change in percent median body mass index (%mBMI), and rates of refeeding hypophosphatemia were analyzed between groups.
Results
A total of 125 adolescents with AN were analyzed with 61 (52%) patients in the HCR group. Mean age was 14.0 years (SD =1.5) and mean presenting %mBMI was 73.2 (SD =6.9) with mean length of stay of 11.9 days (SD = 6.6). Patients in the HCR group had significantly increased rate of change of %mBMI (M = 0.39, SD = 0.31) than patients in the LCR group (M = 0.12, SD = 0.43) (p < .001). There was an increased rate of mild hypophosphatemia in the HCR group (HCR: 46%, LCR: 22%, p = .007) but no difference in rates of moderate hypophosphatemia and no cases of severe hypophosphataemia. Lower presenting %mBMI significantly predicted the phosphate levels (p = .004).
Discussion
In a sample of Asian adolescents with AN, use of an HCR protocol was associated with improved rate of inpatient weight gain. There was increased risk of mild hypophosphataemia, but not moderate to severe hypophosphataemia, suggesting that an HCR protocol can be used safely with close monitoring of phosphate levels.
A hydrogel-based solar vapor generator (SVG) system, without any additional energy input, is a promising alternative to current energy intensive desalination technologies. Thermal and water ...management govern the performance of SVG systems. However, considerable efforts have been devoted to improving thermal management to achieve high evaporation rates, while the research on the water management of hydrogels is still in its early stages, hindering the development of advanced SVGs. Through systematic selection of polymer precursors with appropriate glass transition temperature (
T
g
), here we developed a novel cryogel SVG system with desired properties for water management, such as interconnected pores, rapid-water-replenishment, a high intermediate water ratio
etc
. As a result, the resultant cryogels exhibit a high intermediate water content of 67%, a low equivalent evaporation enthalpy of 861.5 J g
−1
, an excellent evaporation rate of 3.59 kg m
−1
h
−1
under one sun, high salt resistance and long-term durability in desalination, showing great potential for practical applications.
By selecting appropriate polymer precursors, we developed a novel cryogel solar vapor generator for seawater desalination with high intermediate water content for lower evaporation enthalpy and interconnected macropores for rapid water replenishment.
Without requiring any extra energy, a polymeric hydrogel based solar vapor generator (SVG) offers a promising complement to current energy-intensive desalination processes. The hydrophilic groups of ...polymer hydrogels can interact with water molecules through hydrogen bonding, thereby activating other adjacent water molecules to an intermediate water state, thus lowering the total enthalpy of water and making it easier to evaporate. However, there is still a knowledge gap in the structureproperty relationships between hydrogel functional groups and water molecules. Here, we prepare seven hydrogels containing different functional groups, fairly compare their hydration ability and establish the relationship between the hydrophilic groups and the properties (
e.g.
, evaporation enthalpy, electrostatic potential,
etc.
) of the corresponding polymer hydrogels, as well as their solar evaporation performance. The resultant polyacrylamide (PAM) SVG with NH
2
groups, standing out from the other hydrogels, shows rapid water replenishment capability, a high intermediate water content of 78.2%, low equivalent water vaporization enthalpy, an excellent seawater evaporation rate of 3.41 kg m
1
h
1
, and excellent desalination capacity to reduce the main ion concentrations by 35 orders. We expect that this fundamental research could provide guidance for the development of future SVGs and ultimately contribute to the development of efficient solar vapor generation systems.
We correlated the hydration ability of different hydrophilic groups to the varying performance of their corresponding hydrogels in solar vapor generation (SVG), establishing the relationships between the chemical structure, hydration property, and applications.
Objective
There is a growing body of research regarding the situations that are linked to personality expression in daily life. We examined racialized young adults' experiences of racial and ethnic ...cues, and variables from prior personality expression research.
Method
We assessed Big Five personality states in racialized undergraduate students (N = 180) in the Greater Toronto Area, Canada using experience sampling methodology. Participants (Mage = 19.85‐years‐old; 51% South Asian, 17% East Asian, 11% African, 11% Middle Eastern, 9% Southeast Asian, 8% Black‐North American, 5% Caribbean, 3% Afro‐Caribbean, 2% Central American, 2% White/European, 1% South American, 1% North African, 1% South and Central American, 1% Afro‐European, 3% another) provided five assessments daily over 12 days (Nobservations = 6980).
Results
We observed within‐person associations from past personality expression research (e.g., participants exhibited greater conscientiousness when at school). Racial and ethnic cues from previous studies of racial and ethnic identity, stereotyping, discrimination, and prejudice were associated with situational characteristics (e.g., being in a majority White space was associated with being in public), and with Big Five personality states (e.g., racial identity salience was associated with extraversion).
Conclusion
Results suggest that assessing sociocultural variables beyond the individual provides an opportunity for better understanding personality expression.
BackgroundCongenital insensitivity to pain (CIP) is a rare extreme phenotype characterised by an inability to perceive pain present from birth due to lack of, or malfunction of, nociceptors. PRDM12 ...has recently been identified as a new gene that can cause CIP. The full phenotype and natural history have not yet been reported.MethodsWe have ascertained five adult patients and report their clinical features.ResultsBased on our findings, and those of previous patients, we describe the natural history of the PRDM12-CIP disorder, and derive diagnostic and management features to guide the clinical management of patients.ConclusionsPRDM12-CIP is a distinct and diagnosable disorder, and requires specific clinical management to minimise predictable complications.
A low cost, highly flexible and environmentally friendly water generation method known as interfacial solar steam generation (SSG) has recently been popularized by many researchers due to the ...continuously increasing water demand and widening wealth gap around the world. In this perspective, factors determining SSG performance are gathered and highlighted in two different categories, heat and water management. This perspective also identifies challenges that hinder the practical applications of SSG, such as the lack of a standardized energy conversion efficiency calculation, understanding the water evaporation mechanism, understanding the heat flow from the ambient environment to the three-dimensional SSG, focusing solely on the evaporation rate (
R
v
) while ignoring vapor collection efficiency, and the relatively single function that is unable to cope with complex external environments (
i.e.
, anti-fouling). This perspective also discusses current trends in multifunctional applications of SSGs, such as antimicrobial and energy generation properties, and provides insights into future research prospects for SSGs.
This perspective highlights the challenges and opportunities in interfacial evaporation, heat and water management, materials synthesis, and device development for solar steam generation.
Our increasing water demand has been an ongoing critical challenge due to water usages in areas such as industrial, agriculture, and domestic household. Conventional water production faces ...challenges, such as high investment, energy consumption, and brine discharge that may be unsustainable in the future. Solar steam generation (SSG) has been recently proposed by many researchers due to their sustainable and green water production method. Here we demonstrated the use of simple manufacturing and low-cost dual-layer hydrogel (DLH) system containing a double network of positive charged poly-2-(acryloyloxy)ethyl trimethyl ammonium chloride (PAETAC) and polyvinyl alcohol (PVA) bottom layer for fast water transport, as well as a broad light absorbing and heat generating PVA/graphene oxide (GO) top layer for fast water evaporation. As a result, the DLH was able to generate a high 3.12 kg m−2 h−1 water evaporation with 92% efficiency under 1 sun (kW m−2) exposure. Furthermore, this DLH design allows for a safe and passive anti-salt and bacterial property due to PAETAC cationic chain, eliminating 99% salt and bacteria via Donnan repulsion and electrostatic interaction without the need of sunlight exposure.
Display omitted
Abstract
The HR 2562 system is a rare case where a brown dwarf companion resides in a cleared inner hole of a debris disk, offering invaluable opportunities to study the dynamical interaction between ...a substellar companion and a dusty disk. We present the first ALMA observation of the system as well as the continued Gemini Planet Imager monitoring of the companion’s orbit with six new epochs from 2016 to 2018. We update the orbital fit, and in combination with absolute astrometry from GAIA, place a 3
σ
upper limit of 18.5
M
J
on the companion’s mass. To interpret the ALMA observations, we used radiative transfer modeling to determine the disk properties. We find that the disk is well resolved and nearly edge-on. While the misalignment angle between the disk and the orbit is weakly constrained, due to the short orbital arc available, the data strongly support a (near) coplanar geometry for the system. Furthermore, we find that the models that describe the ALMA data best have inner radii that are close to the companion’s semimajor axis. Including a posteriori knowledge of the system’s SED further narrows the constraints on the disk’s inner radius and places it at a location that is in reasonable agreement with (possibly interior to) predictions from existing dynamical models of disk truncation by an interior substellar companion. HR 2562 has the potential over the next few years to become a new test bed for dynamical interaction between a debris disk and a substellar companion.
PDF
