Effects of driver's braking behavior by the real-time pedestrian scale warning system.

A driver warning system can improve pedestrian safety by providing drivers with alerts about potential hazards. Most driver warning systems have primarily focused on detecting the presence of pedestrians, without considering other factors, such as the pedestrian's gender and speed, and whether pedestrians are carrying luggage, that can affect driver braking behavior. Therefore, this study aims to investigate how driver braking behavior changes based on the information about the number of pedestrians in a crowd and examine if a developed warning system based on this information can induce safe braking behavior. For this purpose, an experiment scenario was conducted using a virtual reality-based driving simulator and an eye tracker. The collected driver data were analyzed using mixed ANOVA to derive meaningful conclusions. The research findings indicate that providing information about the number of pedestrians in a crowd has a positive impact on driver braking behavior, including deceleration, yielding intention, and attention. Particularly, It was found that in scenarios with a larger number of pedestrians, the Time to Collision (TTC) and distance to the crosswalk were increased by 12%, and the pupil diameter was increased by 9%. This research also verified the applicability of the proposed warning system in complex road environments, especially under conditions with poor visibility such as nighttime. The system was able to induce safe braking behavior even at night and exhibited consistent performance regardless of gender. In conclusion, considering various factors that influence driver behavior, this research provides a comprehensive understanding of the potential and effectiveness of a driver warning system based on information about the number of pedestrians in a crowd in complex road environments.

Effect of Hydroxyapatite Nanoparticles and Nitrogen Plasma Treatment on Osteoblast Biological Behaviors of 3D-Printed HDPE Scaffold for Bone Tissue Regeneration Applications.

The need for the repair of bone defects has been increasing due to various causes of loss of skeletal tissue. High density polyethylenes (HDPE) have been used as bone substitutes due to their excellent biocompatibility and mechanical strength. In the present study, we investigated the preosteoblast cell proliferation and differentiation on the adding nano-hydroxyapatite (n-HAp) particles into HDPE scaffold and treating HDPE/n-HAp scaffolds with nitrogen (N2) plasma. The three-dimensional (3D) HDPE/n-HAp scaffolds were prepared by fused modeling deposition 3D printer. The HDPE/n-HAp was blended with 10 wt% of n-HAp particle. The scaffold surface was reactive ion etched with nitrogen plasma to improve the preosteoblast biological response in vitro. After N2 plasma treatment, surfaces characterizations were investigated using Fourier transform infrared spectroscopy, scanning electron microscopy, and atomic force microscopy. The proliferation and differentiation of preosteoblast (MC3T3-E1) cells were evaluated by MTT assay and alkaline phosphatase (ALP) activity. The incorporation of n-HAp particles and N2 plasma surface treatment showed the improvement of biological responses of MC3T3-E1 cells in the HDPE scaffolds.

Enhanced Atmospheric Water Harvesting with Sunlight-Activated Sorption Ratcheting.

The global challenge of clean water scarcity needs to be confronted with novel sustainable, climate neutral solutions, over the entire spectrum of possible clean water availability. Atmospheric moisture represents a major untapped resource that can be harvested by sorbents, enabling water production in dry inland regions where it is needed. While benefiting from the utilization of an important renewable energy source, solar-driven, sorbent-based atmospheric water harvesting systems are inseparably based on a single water harvesting cycle per day, which severely limits the daily water productivity and the competitiveness of this very promising technology. Here, we rationally design an atmospheric water harvesting strategy, using durable hydrogel sorbents, that operates with sorption "ratcheting"─a large sequence of rapid adsorption and subsequent desorption steps─activated by direct sunlight. Employing theoretical considerations, we tailor the ratcheting timescales to the inherent sorption properties of the hydrogels, optimally exploiting their natural harvesting capabilities, while maintaining the sustainable utility of the daily cycle. Amplified by the favorable sorption properties and ratcheting stability of the sorbent, this strategy demonstrates an impressive ∼80% increase in water harvesting yield over the daily cycle systems. The generic nature of the ratcheting concept shows great potential to advance the water harvesting capabilities of a range of related systems.

Clinical Impact of an Analytic Tool for Predicting the Fall Risk in Inpatients: Controlled Interrupted Time Series.

BACKGROUND: Patient falls are a common cause of harm in acute-care hospitals worldwide. They are a difficult, complex, and common problem requiring a great deal of nurses' time, attention, and effort in practice. The recent rapid expansion of health care predictive analytic applications and the growing availability of electronic health record (EHR) data have resulted in the development of machine learning models that predict adverse events. However, the clinical impact of these models in terms of patient outcomes and clinicians' responses is undetermined. OBJECTIVE: The purpose of this study was to determine the impact of an electronic analytic tool for predicting fall risk on patient outcomes and nurses' responses. METHODS: A controlled interrupted time series (ITS) experiment was conducted in 12 medical-surgical nursing units at a public hospital between May 2017 and April 2019. In six of the units, the patients' fall risk was assessed using the St. Thomas' Risk Assessment Tool in Falling Elderly Inpatients (STRATIFY) system (control units), while in the other six, a predictive model for inpatient fall risks was implemented using routinely obtained data from the hospital's EHR system (intervention units). The primary outcome was the rate of patient falls; secondary outcomes included the rate of falls with injury and analysis of process metrics (nursing interventions that are designed to mitigate the risk of fall). RESULTS: During the study period, there were 42,476 admissions, of which 707 were for falls and 134 for fall injuries. Allowing for differences in the patients' characteristics and baseline process metrics, the number of patients with falls differed between the control (n=382) and intervention (n=325) units. The mean fall rate increased from 1.95 to 2.11 in control units and decreased from 1.92 to 1.79 in intervention units. A separate ITS analysis revealed that the immediate reduction was 29.73% in the intervention group (z=-2.06, P=.039) and 16.58% in the control group (z=-1.28, P=.20), but there was no ongoing effect. The injury rate did not differ significantly between the two groups (0.42 vs 0.31, z=1.50, P=.134). Among the process metrics, the risk-targeted interventions increased significantly over time in the intervention group. CONCLUSIONS: This early-stage clinical evaluation revealed that implementation of an analytic tool for predicting fall risk may to contribute to an awareness of fall risk, leading to positive changes in nurses' interventions over time. TRIAL REGISTRATION: Clinical Research Information Service (CRIS), Republic of Korea KCT0005286; https://cris.nih.go.kr/cris/search/detailSearch.do/16984.

Comparative analysis of allele variation using allele frequencies according to sample size in Korean population.

BACKGROUND: Allele frequency using short tandem repeats (STRs) is used to calculate likelihood ratio for database match, to interpret DNA mixture and to estimate ethnic groups in forensic genetics. In Korea, three population studies for 23 STR loci have been conducted with different sample size for forensic purposes. OBJECTIVE: We performed comparative analysis to determine how the difference of sample size affects the allele frequency and allele variation within same ethnic population (i.e. Korean). Furthermore, this study was conducted to check how the sampling group and multiplex kit also affect allele variation such as rare alleles and population specific alleles. METHODS: To compare allele variation, we used allele frequencies of three population data published from three Korean forensic research groups. Allele frequencies were calculated using different sample sizes and multiplex kits: 526, 1000, and 2000 individuals, respectively. RESULTS: The results showed the different distribution of allele frequencies in some loci. There was also a difference in the number of rare alleles observed by the sample size and sampling bias. In particular, an allele of 9.1 in the D2S441 locus was not observed in population study with 526 individuals due to multiplex kits. CONCLUSION: Because the allele frequencies play an important role in forensic genetics, even if the samples are derived from the same population, it is important to consider the effects of sample size, sampling bias, and selection of multiplex kits in population studies.

Bibliometrics and Co-Citation Network Analysis of Systematic Reviews of Evidence-Based Nursing Guidelines for Preventing Inpatient Falls.

Advances in bibliometrics and co-citation analysis provide the opportunity to analyze quantitatively the large amount of nursing research used in evidence-based nursing. Numerous nursing researchers have attempted to obtain evidence that using evidence-based nursing improves the quality of nursing practices. However, little is known about how these efforts comply with the rigorous methods required for a systematic review in a subject area. This study explored the comprehensiveness of systematic reviews in four guidelines for preventing inpatient falls using bibliometrics and a co-citation network technique. Citations (n = 659) and 9417 unique bibliographic records written by 6537 authors were collected from the guidelines in January 2020. The results showed none of the references spanned all four authoring bodies, whereas only 0.1% and 4.7% of the references spanned three and two of the authoring bodies, respectively. The co-citation analysis revealed differences in the scope and primary concerns among the development groups, even in the same setting, with differences in the highly influential articles and authors. These findings imply that although the systematic reviews of guidelines on fall prevention were of good quality, there remain areas for improvement in terms of harmonizing the selection of bibliographic citations comprehensively.

Exploiting radiative cooling for uninterrupted 24-hour water harvesting from the atmosphere.

Atmospheric water vapor is ubiquitous and represents a promising alternative to address global clean water scarcity. Sustainably harvesting this resource requires energy neutrality, continuous production, and facility of use. However, fully passive and uninterrupted 24-hour atmospheric water harvesting remains a challenge. Here, we demonstrate a rationally designed system that synergistically combines radiative shielding and cooling-dissipating the latent heat of condensation radiatively to outer space-with a fully passive superhydrophobic condensate harvester, working with a coalescence-induced water removal mechanism. A rationally designed shield, accounting for the atmospheric radiative heat, facilitates daytime atmospheric water harvesting under solar irradiation at realistic levels of relative humidity. The remarkable cooling power enhancement enables dew mass fluxes up to 50 g m-2 hour-1, close to the ultimate capabilities of such systems. Our results demonstrate that the yield of related technologies can be at least doubled, while cooling and collection remain passive, thereby substantially advancing the state of the art.

A forensic case study for body fluid identification using DNA methylation analysis.

Recently, a method of identifying body fluids using DNA methylation has been developed (Frumkin et al., 2011). An existing multiplex assay using 9 CpG markers could differentiate 5 body fluids: semen, blood, saliva, menstrual blood, and vaginal fluid. To validate this technique, we evaluated the previously described body fluid identification method by means of single base extension (SBE). DNA methylation was applied to 22 samples in 18 forensic cases; seven of these were semen, three were blood, eight were saliva, three were vaginal fluid, and one was menstrual blood. Total of 18 samples were tested, the DNA methylation profiles were coincident from preliminary tests (acid phosphatase (AP), leucomalachite green (LMG, Sigma Aldrich, St Louis, MO, USA) and SALIgAE®) except one sample which displayed an all-negative result. After applying the DNA methylation method to forensic samples, we determined that it could be very useful for differentiating vaginal secretions from menstrual blood, for which there is no conventional preliminary testing method.

Correction to: Development and forensic validation of human genomic DNA quantification kit.

The above article was published with two author names being incorrect. The published paper states "'Hyeun Kyu Yoon and Ki min Seong", whereas it should be "'Hyun Kyu Yoon and Ki Min Seong".

Development and forensic validation of human genomic DNA quantification kit.

DNA quantification is an essential step for successful multiplex short tandem repeat (STR) polymerase chain reactions (PCR), which are used for confirming identities using human genomic DNA. The new DNA quantification kit, named the National Forensic Service Quantification (NFSQ) kit, simultaneously provides total human DNA concentration, human male DNA concentration, and a DNA degradation index (DI) using multiplex TaqMan fluorescent probes. The NFSQ was validated according to developmental validation guidelines from the SWGDAM and MIQE. NFSQ detected up to 0.00128 ng/µL and could detect male DNA up to a 1:8000 ratio of male to female DNA. In PCR inhibitor tests, NFSQ could measure DNA at a concentration of 200 ng/µL of humic acid and 600 µM of hematin. The NFSQ kit showed a DI value trend similar to other qPCR kits. In the reproducibility study, the coefficient of variation of the NFSQ kit was within 10%. The quantitative results of the casework samples obtained using the NFSQ kit were consistent with the STR interpretation results. The NFSQ kit can be useful in the human identification process, as it has detection capabilities similar to those of other comparable quantification kits.

Genetic variation for three Y-STR loci: DYS390, DYS518, and DYS643.

Y chromosome short tandem repeats (Y-STRs) are commonly used to analyze male-specific DNA. Although biallelic patterns due to duplication events have been detected at some loci, Y-STRs generally appear as a single peak except for DYS385 because the Y chromosome is haploid. STR loci in regions of segmental duplication by homologous recombination on the Y chromosome exhibit double allelic peaks, rather than single peaks. In this study, we report a bi- and triallelic pattern observed simultaneously in DYS390, DYS518, and DYS643. A bi- and triallelic pattern has not previously been observed simultaneously for these three loci. We also identified the copy number variation in the region including these loci by the microarray-based analysis. Given the peak balance pattern, the copy number variation, and the close position of these three loci on the Y chromosome, we consider that this phenomenon is caused by a segmental duplication in the euchromatin region. By ruling out mixed samples, a common interpretation of multiple peaks, these results have practical implications for the interpretation of Y-STR results in forensics analyses.

Mechanical Fatigue Resistance of Piezoelectric PVDF Polymers.

The fatigue resistance of piezoelectric PVDF has been under question in recent years. While some report that a significant degradation occurs after 106 cycles of repeated voltage input, others report that the reported degradation originates from the degraded metal electrodes instead of the piezoelectric PVDF itself. Here, we report the piezoelectric response and remnant polarization of PVDF during 107 cycles of repeated compression and tension, with silver paste-based electrodes to eliminate any electrode effect. After applying repeated tension and compression of 1.8% for 107 times, we do not observe any notable decrease in the output voltage generated by PVDF layers. The results from tension experiments show stable remnant polarization of 5.5 µC/cm², however, the remnant polarization measured after repeated compression exhibits a 7% decrease as opposed to the tensed PVDF. These results suggest a possible anisotropic response to stress direction. The phase analyses by Raman spectroscopy reveals no significant change in the phase content, demonstrating the fatigue resistance of PVDF.

Rapid oral bacteria detection based on real-time PCR for the forensic identification of saliva.

This study developed a new method for forensic saliva identification using three oral bacteria, Streptococcus salivarius, Streptococcus sanguinis, and Neisseria subflava, combined with a real-time polymerase chain reaction (RT-PCR) system we called OB mRT-PCR. Analytical sensitivity results showed that the target bacteria were amplified at 102-107 copies/reaction, and analytical specificity was assessed using 24 other viruses, bacteria, and protozoa. To evaluate the OB mRT-PCR kit for forensic applications, saliva from 140 Korean individuals was tested, and at least two target bacteria were detected in all the samples. Additional studies on non-saliva samples demonstrated the specificity of the kit. Comparison of the kit with two conventional saliva test methods, the SALIgAE and RSID-Saliva assays, indicated that it was more sensitive and applicable to saliva samples in long-term storage (up to 14 weeks). Additionally, through amplification of mock forensic items and old DNA samples (isolated without lysis of the bacterial cells, regardless of their Gram-positivity), we found that the kit was applicable to not only saliva swabs, but also DNA samples. We suggest that this simple RT-PCR-based experimental method is feasible for rapid on-site analysis, and we expect this kit to be useful for saliva detection in old forensic DNA samples.

Enhanced sensitivity of CpG island search and primer design based on predicted CpG island position.

DNA methylation has important biological roles, such as gene expression regulation, as well as practical applications in forensics, such as in body fluid identification and age estimation. DNA methylation often occurs in the CpG site, and methylation within the CpG islands affects various cellular functions and is related to tissue-specific identification. Several programs have been developed to identify CpG islands; however, the size, location, and number of predicted CpG islands are not identical due to different search algorithms. In addition, they only provide structural information for predicted CpG islands without experimental information, such as primer design. We developed an analysis pipeline package, CpGPNP, to integrate CpG island prediction and primer design. CpGPNP predicts CpG islands more accurately and sensitively than other programs, and designs primers easily based on the predicted CpG island locations. The primer design function included standard, bisulfite, and methylation-specific PCR to identify the methylation of particular CpG sites. In this study, we performed CpG island prediction on all chromosomes and compared CpG island search performance of CpGPNP with other CpG island prediction programs. In addition, we compared the position of primers designed for a specific region within the predicted CpG island using other bisulfite PCR primer programs. The primers designed by CpGPNP were used to experimentally verify the amplification of the target region of markers for body fluid identification and age estimation. CpGPNP is freely available at http://forensicdna.kr/cpgpnp/.

Selective engineering of oxygen-containing functional groups using the alkyl ligand oleylamine for revealing the luminescence mechanism of graphene oxide quantum dots.

Oxygen-containing functional groups such as epoxy, hydroxyl, carboxylic, and carboxyl groups have a great influence on the luminescence properties of graphene oxide quantum dots (GOQDs). Understanding their roles is essential for the design and optimization of GOQD performance. Herein, we investigate the effect of epoxide functional groups in GOQDs on the luminescence mechanism through passivation of the epoxide functional groups using the alkyl ligand oleylamine. Luminescence in the as-synthesized GOQDs has two separate origins: intrinsic states derived from localized sp2 carbon subdomains and extrinsic states formed by oxygen-functional groups. When the oleylamine ligand is conjugated on the GOQDs, intrinsic PL emission from the localized sp2 carbon subdomains decreases. This is discussed in detail, based on optical characterization and first-principles density functional theory calculations, which reveal that the role of the epoxide functional groups is to form localized sp2 carbon subdomains emitting intrinsic PL. To the best of our knowledge, this is the first investigation of the role of epoxide functional groups on the luminescence mechanism in GOQDs.

Shaping micro-clusters via inverse jamming and topographic close-packing of microbombs.

Designing topographic clusters is of significant interest, yet it remains challenging as they often lack mobility or deformability. Here we exploit the huge volumetric expansion (up to 3000%) of a new type of building block, thermally expandable microbombs. They consist of a viscoelastic polymeric shell and a volatile gas core, which, within structural confinement, create micro-clusters via inverse jamming and topographical close-packing. Upon heating, microbombs anchored in rigid confinement underwent balloon-like blowing up, allowing for dense clusters via soft interplay between viscoelastic shells. Importantly, the confinement is unyielding against the internal pressure of the microbombs, thereby enabling self-assembled clusters, which can be coupled with topographic inscription to introduce structural hierarchy on the clusters. Our strategy provides densely packed yet ultralight clusters with a variety of complex shapes, cleavages, curvatures, and hierarchy. In turn, these clusters will enrich our ability to explore the assemblies of the ever-increasing range of microparticle systems.Self-assembled systems are normally composed of incompressible building blocks, which constrain their space filling efficiency. Yu et al. show programmable, densely packed clusters using thermally expandable soft microparticles, whereby the self-assembling process is realized via a jamming transition.

Multidirectional Wrinkle Patterns Programmed by Sequential Uniaxial Strain with Conformal yet Nontraceable Masks.

Surface wrinkling is a promising route to control the mechanical, electrical, and optical properties of materials in a wide range of applications. However, previous artificial wrinkles are restricted to single or random orientation and lacks selectivity. To address this challenge, this study presents multidirectional wrinkle patterns with high selectivity and orientation through sequential uniaxial strain with conformal polymeric shadow masks. The conformal but nontraceable polymeric stencil with microapertures are adhered to a flat substrate prior to oxidation, which forms discrete and parallel wrinkles in confined domains without any contamination. By fully investigating the process, this study displays compound topography of wrinkles consisting of wrinkle islands and surrounding secondary wrinkles on the same surface. With this topography, various diffusion properties are presented: from semi-transparent yet diffusive films to multidirectional diffusive films, which will be available for new types of optical diffuser applications.

Evaluation of forensic genetic parameters of 12 STR loci in the Korean population using the InvestigatorⓇ HDplex kit.

We genotyped and calculated the forensic parameters of 10 non-CODIS loci and 2 CODIS loci of 990 Korean individuals using the InvestigatorⓇ HDplex kit. No significant deviations from Hardy-Weinberg equilibrium (after Bonferroni correction for multiple testing) or genetic linkage disequilibrium were observed. The calculated matching probability and power of discrimination ranged from 0.0080 to 0.2014, and 0.7986 to 0.9920, respectively. We conclude that the markers of the kit are highly informative corroborative tools for forensic DNA analysis.

Nonlinear Frameworks for Reversible and Pluripotent Wetting on Topographic Surfaces.

Soft, ultrathin frameworks nonlinearly organized in tandem are presented to realize both reversible and pluripotent wetting on topographic surfaces. A design rule is introduced by establishing and proving the theoretical model upon hierarchical textures. Nonlinear frameworks can be conformally and reversibly wet upon complex topography in nature, thereby overcoming the wetting problems in previous conventional solid systems.

Forensic genetic study of 29 Y-STRs in Korean population.

In this study, we compared two recently released commercial Y-chromosomal short tandem repeat (Y-STR) kits: the PowerPlex Y23 System (PPY23) and Yfiler® Plus PCR amplification kit (YPlus). We performed validation studies, including sensitivity, tolerance to PCR inhibitors, and mixture analysis, and a population genetics study using 306 unrelated South Korean males. PPY23 and YPlus showed similar sensitivity, but PPY23 showed higher tolerance to humic acid than YPlus. Furthermore, the detection rate of unique minor alleles called from male/male mixtures was higher for PPY23 than for YPlus. Comparing the newly added loci, the mean values of gene diversity for PPY23 and YPlus were 0.6715 and 0.8158, respectively. The discrimination capacity in the 306 unrelated South Korean males for PPY23 was 0.9837, and that for YPlus was 0.9935. These results will inform the selection of suitable Y-STR kits based on the purpose of forensic DNA analysis.