The purpose of this study was to explore and identify patterns of risk predictors of maltreatment recurrence using predictive risk modeling (PRM). This study used the administrative dataset from the ...National Child Maltreatment Information System recorded by Korean CPS (Child Protective Service) workers. The information, including recurrent maltreatment, was collected in 2012; then, those reported cases were followed for 2 years through 2014. The data included information about child, family, caregiver, maltreatment, and service characteristics and consisted of male (50.22%) and female (49.78%) children with an average age of 9 years (
n
= 4319). We examined the association of risk factors with recurrence using conditional inference trees (CTREE): a tree-based data mining algorithm for classification that allows the exploration of the interconnection between hypothesized risk factors. Study findings showed that a history of prior CPS involvement was the first decision point in the decision tree structure of recurrence. The effect of other risk factors depended on the presence of prior CPS involvement. In the absence of prior CPS involvement, cases with (a) a single-parent status and (b) a caregiver’s alcohol abuse living in other types of households (two-parent households, kinship care, and children without parents) were associated with recurrence. In the presence of prior CPS involvement, cases with out-of-home care or others (long- or short-term foster care and emergency placement) in the final decision of child placement (a) where in-home care in the initial decision of child placement within the presence of physical abuse and (b) where social isolation without physical abuse was related to recurrence. Cases with (a) a male caregiver and (b) a female caregiver with social isolation and without social isolation yet employed were at high risk for recurrence under the circumstance of in-home care in the final decision of child placement. This exploratory study found multiple connections among the factors in the prediction of recurrence. The CTREE helps unravel the complexity embedded in maltreatment recurrence by capturing its patterns. This information can deepen our knowledge of associations between risk factors in the prediction of recurrence and be used as a reference to inform child maltreatment policy and prevention.
•We report a novel SERS-based lateral flow (LF) assay for the sensitive detection of bacterial pathogens.•Quantitative analysis of low-abundance target bacteria is possible using this SERS assay ...platform.•This approach provides new insights into early detection of specific bacterial pathogens in the field.
Bacterial pathogens such as Yersinia pestis, Francisella tularensis, and Bacillus anthracis are classified into the highest rank of potential bioterrorism agents. Colorimetric lateral flow assay (LFA) strips are commercially available but these conventional strips have drawbacks in terms of low sensitivity and limit of quantitative analysis. Therefore, there is an urgent need for a new sensing platform to detect these pathogens in the early contamination stage. In this study, a novel surface-enhanced Raman scattering (SERS)-based LFA strip was developed for sensitive detection of bacterial pathogens. Target-specific SERS nanotags (Raman reporter-labeled gold nanoparticles) were used as an alternative to the gold nanoparticles in conventional LFA strips. Using these SERS nanotags the presence of bacteria could be identified through a simple color change in the test line. Additionally, highly sensitive and accurate quantitative analysis could be performed by monitoring the characteristic Raman peak intensity of SERS nanotags that were captured in the test line. This highly sensitive method required a short assay time (15 min) and a tiny volume of pathogen sample (40 μL). We believe that the proposed SERS-based LFA technique has great potential as a valuable tool in the early detection of specific bacterial pathogens in the field due to its excellent analytical sensitivity.
Background
Despite extensive research examining features of adolescents’ ego-identity development, little research has demonstrated patterns of ego-identity development and its relationship with ...various individual and environmental factors that are theoretically important for identity development.
Objective
The current study investigated developmental trajectories of ego-identity and the longitudinal relationship between multiple predictors (Korean language proficiency, sex/gender, logged household income, and child maltreatment) and ego-identity development.
Methods
Data from three time points (Time 1 = 9th grade; Time 2 = 11th grade; Time 3 = 12th grade) of the Korean Children and Youth Panel Survey (N = 7053) were used. The mean age of participants in each wave was 15, 17, and 18 years old.
Results
The results showed that the level of ego-identity development varied across times—that the developmental pattern plateaued and decreased slightly after Time 2. A significant association between Korean language proficiency and ego-identity development was found, indicating that individuals who reported a higher level of Korean language proficiency displayed a greater level of ego-identity over the three observation periods. Sex/gender, logged household income, and child maltreatment were significantly associated with ego-identity development at the initial level.
Conclusion
The findings highlight the importance of identifying patterns of ego-identity development and understanding its association with multiple predictors.
End-group cross-linked sulfonated poly(arylene ether sulfone) (SPAES) membranes were prepared using thiol capped SPAES (SH-SPAES) with different amounts of vinyl polysulfone (VPSf) as a polymeric ...cross-linker. The cross-linked membranes showed remarkably improved physicochemical stabilities compared to the corresponding linear SPAES membrane. Although the proton conductivity of the SPAES membrane composed of SPAES with the degree of sulfonation (DS) as 70 mol% could not be measured due to its low physical stability under the measurement condition, those of the cross-linked membranes were repeatedly evaluated due to the enhanced stability through the formation of cross-linked structures. The obtained proton conductivity values from cross-linked membranes are larger than those of the linear SPAES membrane which composed of SPAES with DS of 50 mol% having the ion exchange capacity (IEC) similar to that of the cross-linked membranes, especially at relative low humidity conditions. Furthermore, the fuel cell performance of the membrane electrode assembly (MEA) prepared with the cross-linked membrane, showing the optimized physicochemical stabilities and proton conductivity exhibited a maximum power density of 692 mW cm−2, which was larger than that with Nafion 212 (603 mW cm−2) at 80 °C under fully humidified H2/Air condition.
•Thiol group capped highly sulfonated poly(arylene ether sulfone) and vinyl group containing poly sulfone were synthesized.•End group cross-linked membranes were prepared by thiol-ene click reaction using polymeric cross-linker.•Excellent physicochemical stability of end group cross-linked membranes.•High proton conductivity of end group cross-linked membranes in low humidity condition.•Outstanding cell performance of MEA prepared with end group cross-linked membrane.
Layered cobalt (oxy)hydroxides have received much attention as cost-effective and efficient catalysts for the oxygen evolution reaction (OER) for electrochemical water splitting. Doping with guest ...cations possessing different oxidation states such as Ag can change the chemistry of conventional transition metal oxides and hydroxides, generating unexpected electrocatalytic performances. However, Ag dopants have been found to easily segregate at the surface of electrocatalysts, which induces deactivation. Here, we fabricated Ag-doped CoOOH nanosheet arrays using electrochemical deposition, followed by a simple electrochemical diffusion approach. Surprisingly, we revealed, through atom probe tomography (APT), secondary ion mass spectroscopy (SIMS), and energy-dispersive spectroscopy (EDS) that Ag atoms are homogeneously distributed without any detectable segregation. The Ag-doped CoOOH exhibits enhanced OER performance in terms of overpotential, both experimentally (256 mV) and theoretically (60 mV). The homogeneously distributed Ag dopants facilitate the phase transformation from Co(OH)2 to the active phase of CoOOH. Calculations show that Ag doping enhances phase stability of CoOOH and exposed Ag dopants act as active sites by releasing −OH adsorbates.
Rapid and sensitive detection of botulinum neurotoxins (BoNTs) is important for immediate treatment with proper antitoxins. However, it is difficult to detect BoNTs at the acute phase of infection, ...owing to its rarity and ambiguous symptoms. To resolve this problem, we developed a surface-enhanced Raman scattering (SERS)-based immunoassay technique for the rapid and sensitive detection of BoNTs. Magnetic beads and SERS nanotags as capture substrates and detection probes, respectively, and Nile Blue A (NBA) and malachite green isothiocyanate (MGITC) as Raman reporter molecules were used for the detection of two different types of BoNTs (types A and B), respectively. The corresponding limits of detection (LODs) were determined as 5.7 ng/mL (type A) and 1.3 ng/mL (type B). Total assay time, including that for immunoreaction, washing, and detection, was less than 2 h.
An active vibration-isolation system (AVIS) utilizes a geophone sensor, a type of velocity sensor, to control microvibration. The structure of the sensor is modeled by mass, damper, and spring. The ...mathematical model of the geophone sensor is a second-order model with a resonant frequency. However, at low-band frequencies, the response characteristic is nonlinear and phase delay occurs. Compared with the ideal velocity signals of the system, the velocity signals measured from the geophone sensor were distorted in low-band frequencies. Consequently, this measurement issue in feedback control loops can affect the stability and performance of the AVIS. This paper proposes design rules for a state-variable filter (SVF) that can compensate for the nonlinearity of the geophone sensors in low-band frequencies and evaluates vibration attenuation performance of the AVIS by applying the proposed SVF. To evaluate the effectiveness of the filter in compensating for the nonlinear response of the geophone sensor, we compared Bode plots generated through simulation and experimental results obtained using a dynamic signal analyzer. The experimental results demonstrated that the proposed SVF effectively reduces the resonance peak of the geophone sensor and expands the frequency bands that maintain a constant magnitude in range of 0.8–10 Hz. By applying the geophone sensor with SVF to AVIS, the microvibration attenuation improved to − 18.4 dB near 4.5 Hz.
F-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) is a robust imaging modality used for staging multiple myeloma (MM) and assessing treatment responses. Herein, we ...extracted features from the FDG PET/CT images of MM patients using an artificial intelligence autoencoder algorithm that constructs a compressed representation of input data. We then evaluated the prognostic value of the image-feature clusters thus extracted. Conventional image parameters including metabolic tumor volume (MTV) were measured on volumes-of-interests (VOIs) covering only the bones. Features were extracted with the autoencoder algorithm on bone-covering VOIs. Supervised and unsupervised clustering were performed on image features. Survival analyses for progression-free survival (PFS) were performed for conventional parameters and clusters. In result, supervised and unsupervised clustering of the image features grouped the subjects into three clusters (A, B, and C). In multivariable Cox regression analysis, unsupervised cluster C, supervised cluster C, and high MTV were significant independent predictors of worse PFS. Supervised and unsupervised cluster analyses of image features extracted from FDG PET/CT scans of MM patients by an autoencoder allowed significant and independent prediction of worse PFS. Therefore, artificial intelligence algorithm-based cluster analyses of FDG PET/CT images could be useful for MM risk stratification.
InP/ZnSe/ZnS quantum dots (QDs) stand as promising candidates for advancing QD-organic light-emitting diodes (QLED), but low emission efficiency due to their susceptibility to oxidation impedes ...applications. Structural defects play important roles in the emission efficiency degradation of QDs, but the formation mechanism of defects in oxidized QDs has been less investigated. Here, we investigated the impact of diverse structural defects formation on individual QDs and propagation during UV-facilitated oxidation using high-resolution (scanning) transmission electron microscopy. UV-facilitated oxidation of the QDs alters shell morphology by the formation of surface oxides, leaving ZnSe surfaces poorly passivated. Further oxidation leads to the formation of structural defects, such as dislocations, and induces strain at the oxide-QD interfaces, facilitating In diffusion from the QD core. These changes in the QD structures result in emission quenching. This study provides insight into the formation of structural defects through photo-oxidation, and their effects on emission properties of QDs.
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