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A new design method of an ultra-wideband circularly-polarized planar multiple-input-multiple-output (MIMO) antenna is presented in this paper. The proposed MIMO antenna consists of four unit cell antennas, being comprised of a microstrip feed line and a square slotted ground plane. In the proposed unit cell design, a circular stub is protruded from the ground plane strip for achieving circular polarization. The unit cell of the MIMO antenna is optimized by adjusting design parameters. The compact four-port MIMO antenna prototype is designed on the FR4 substrate with the overall dimensions of 45 × 45 × 1.6 mm3. The proposed four-port MIMO antenna design provides an impedance bandwidth (S11 < −10 dB) of 112% (3.1–11 GHz) and a 3 dB axial ratio bandwidth of 36% (4.8–6.9 GHz). The performance of the fabricated MIMO antenna shows good agreement between the EM simulation and measurement results.
A 5G new radio cellular system is characterized by three main usage scenarios of enhanced mobile broadband (eMBB), ultra-reliable and low latency communications (URLLC), and massive machine type communications, which require improved throughput, latency, and reliability compared with a 4G system. This overview paper discusses key characteristics of 5G channel coding schemes which are mainly designed for the eMBB scenario as well as for partial support of the URLLC scenario focusing on low latency. Two capacity-achieving channel coding schemes of low-density parity-check (LDPC) codes and polar codes have been adopted for 5G where the former is for user data and the latter is for control information. As a coding scheme for data, 5G LDPC codes are designed to support high throughput, a variable code rate and length and hybrid automatic repeat request in addition to good error correcting capability. 5G polar codes, as a coding scheme for control, are designed to perform well with short block length while addressing a latency issue of successive cancellation decoding.
Recent hospital fire incidents in South Korea have heightened the importance of patient evacuation. Moving patients from an intensive care unit (ICU) or emergency department (ED) setting is a challenge due to the complexity of moving acutely unwell patients who are reliant on invasive monitoring and organ support. Despite the importance of patient evacuation, the readiness of ICU and ED for urgent evacuation has not been assessed.
To enhance the readiness and competencies of workers from ICU and ED in the evacuation of patients during a simulated tabletop fire exercise.
A tabletop simulation exercise was developed by the Center for Disaster Relief, Training, and Research referencing the fire evacuation manual developed by the hospital’s ICU and ED. The scenario consisted of evacuating patients horizontally and vertically from each department. The participants’ actions were assessed using a checklist. A debriefing was completed after the exercise to discuss the gaps observed. A post-survey questionnaire was used to evaluate the exercise and assess the perception changes of the participants. All pre-to-post differences within subjects were analyzed with paired t-tests.
A total of 22 and 29 people participated in the exercise from ICU and ED, respectively. Knowledge and confidence improved post-exercise for both ICU and ED scenarios (p<0.05). Course satisfaction was 7.9 and 8.7, respectively for ICU and ED exercise. Correct performance rates for ICU and ED were 59% and 58%, respectively. Common gaps noted for both ICU and ED were wearing protective masks, patient hand-over communication, and preparation for resources.
There need to be exercises to recognize system gaps in place for hospital fire evacuation preparedness. Tabletop simulation exercises are ideal tools for this purpose. Although this was a short 90-minute exercise, this increased familiarity with the evacuation plan, tested the plan, and allowed for identification of gaps.
South Korea experienced Middle East Respiratory Syndrome (MERS) outbreak in 2015. To mitigate the threat posed by MERS, the Ministry of Health and Center for Disease Control designated hospitals to be responsible for managing any suspected or confirmed infectious patient. These hospitals receive mandatory training in managing infectious patients, but many of the trainings lack practical skills practice and pandemic preparedness exercise.
To develop and evaluate a training course designed to train healthcare providers from designated hospitals to enhance their competencies in managing emerging infectious diseases and potential outbreaks.
A two-day course was developed by the Center for Disaster Relief, Training, and Research in collaboration with the Korea Health Promotion Institute using Kern’s 6-step approach. The course consisted of didactic lectures, technical skills training, tabletop simulation, and scenario-based simulation. Table-top simulation exercises consisted of cases involving a single infectious patient detected in the outpatient clinic and outbreak in the emergency department. Scenario-based simulation exercises involved managing a critically ill infectious patient in an isolated ward. A post-survey questionnaire was used to evaluate the course and assess the perception changes of the participants. All pre-to-post differences within subjects were analyzed with paired t-tests.
A total of 121 healthcare providers participated in three separate courses. The competencies for pandemic preparedness knowledge, skills, and attitude improved from pre- to post-course. The differences were all statistically significant (p<0.05). Overall course satisfaction in average for expectation, time, delivery method, and contents were 9.5, 9.2, 9.4, and 9.2, respectively.
There needs to be tests and exercises to recognize gaps of systems in place for pandemic preparedness. Simulation exercises are ideal tools for this purpose. Although this was only a two-day intensive course, this increased familiarity with workflows, tested the coordination of workflows between different disciplines and allowed the identification of gaps.
Curiosity and situational interest are powerful driving forces in learning and motivation that lead students to learn more effectively. In this chapter, we elucidate curiosity and situational interest by focusing on (1) conceptual definitions and characteristics, (2) antecedents, (3) cognitive and behavioral outcomes, and (4) strategies to foster them in school. Curiosity is a short-lasting, aversive state that desires an acquisition of specific information. Its properties contrast with those of situational interest, which is an overall positive affect and a general preference for a topic. Whereas curiosity and situational interest are stimulated by similar contextual features (such as collative variables), triggering curiosity requires one to perceive an information gap between what one knows and what one wants to know. Despite these differences, ample evidence displays that both curiosity and situational interest positively impact students’ learning, motivation, creativity, and well-being once triggered. Thus, in closing, integrative and specific pedagogical guidelines to enhance students’ curiosity and situational interest in education practice are suggested.
Despite the possibility that cognitive deficits associated with depression may have different patterns depending on the level of neurocognitive impairment, there remains no clear evidence of this. This study aimed to investigate the differential association between depression and cognitive function in patients with mild cognitive impairment (MCI) and Alzheimer’s disease (AD).
A cross-sectional analysis was performed of data from 1,724 patients with MCI and 1,247 patients with AD from the Clinical Research Center for Dementia in Korea. Depression was assessed using the Korean form of the Geriatric Depression Scale, and cognition was measured using the Seoul Neuropsychological Screening Battery, which includes five domains (attention, language and related function, visuospatial function, memory, and frontal/executive function).
Significant differences were found between the two groups (non-depressed vs. depressed) in visuospatial, memory, and executive function domains in the MCI group, as well as in the attention domain in the AD group. The association between depressive symptoms and cognitive function was significantly greater in patients with MCI than in those with AD. These associations were more pronounced in memory and executive function.
Our findings suggest that the association between depression and decreased cognitive function is more pronounced in MCI than AD.
The complete chloroplast (cp) genome sequences of three Amaranthus species (Amaranthus hypochondriacus, A. cruentus and A. caudatus) were determined by next-generation sequencing. The cp genome sequences of A. hypochondriacus, A. cruentus and A. caudatus were 150,523, 150,757 and 150,523 bp in length, respectively, each containing 84 genes with identical contents and orders. Expansion or contraction of the inverted repeat region was not observed among the three Amaranthus species. The coding regions were highly conserved with 99.3% homology in nucleotide and amino acid sequences. Five genes – matK, accD, ndhJ, ccsA and ndhF – showed relatively high non-synonymous/synonymous values (Ka/Ks > 0.1). Sequence comparison identified two insertion/deletion (InDels) greater than 40 bp in length, and polymerase chain reaction markers that could amplify these InDel regions were applied to diverse Korean Genbank accessions, which could discriminate the three Amaranthus species. Phylogenetic analyses based on 62 protein-coding genes showed that the core Caryophyllales were monophyletic and Amaranthoideae formed a sister group with the Betoideae and Chenopodioideae clade. Comparing each homologous locus among the three Amaranthus species, identified eight regions with high Pi values (>0.03). Seven of these loci, except for rps19-trnH (GUG), were considered to be useful molecular markers for further phylogenetic studies.
Failure at the proximal neck for endovascular aortic repair (EVAR) in abdominal aortic aneurysm (AAA) is more common in the presence of unfavorable proximal neck anatomy. In patients with hostile neck, EndoAnchors provide proximal fixation and reduces potential type I endoleak or endograft migration. However, the population size for AAA patients with hostile anatomic neck among Korean is unknown and cost-analysis with regard to EndoAnchors has not been established.
To figure out the population size of AAA patients with hostile neck anatomy, retrospective medical chart review was conducted from four major medical centers. Hostile proximal aortic neck was defined as any or all of neck length 28 mm, infrarenal neck angulation >60°, ≥50 percent of circumferential thrombus, ≥50 percent of calcified neck, and conical neck. Cost-analysis on EndoAnchor use for treatment purpose was conducted based on Korean National Health Insurance Claims dataset (HIRA-NIS 2015).
Two-hundred and ten patients’ anatomic data treated with EVAR were included; 130 (61.9 percent) patients met the criteria for a hostile aortic neck and 32 (15.2 percent) patients had multiple hostile anatomy parameters. Endograft migration was reported in four (1.9 percent) patients and intra or post-op type I endoleak was reported in 21 (10.0 percent) patients. Based on 1-year claims data, 1,607 patients were treated with EVAR in 2015 and the annual average medical costs for open repair were USD 16,151. Given the patients with type I endoleak or endograft migration needs open repair if not treated with EndoAnchors, the estimated annual costs for patients treated with EndoAnchor were USD 2,234,321 and those for patients without EndoAnchor were USD 2,595,508, therefore USD 361,187 can be saved annually.
The population size with hostile aortic neck in Korea was comparable with those in western countries. Economically, EndoAnchor is a cost-saving treatment for type I endoleak and migration after EVAR from Korean payer.
We investigated potential nosocomial aerosol transmission of severe fever with thrombocytopenia syndrome virus (SFTSV) with droplet precautions. During aerosol generating procedures, SFTSV was be transmitted from person to person through aerosols. Thus, airborne precautions should be added to standard precautions to avoid direct contact and droplet transmission.
Architecture, engineering and construction professional practices (e.g. architectural, engineering and contracting firms and practitioners) have pushed software developers to support standardised data formats and flows for importing, exporting and sharing building data. Recently, the widespread use and proliferation of object-oriented computer-aided design (CAD) packages together with the increased complexity and automation in the construction processes have fostered the uptake and exchange of 3D data during the collaboration process (Singh, Gu and Wang, 2011). Building information modelling (BIM) has facilitated this innovation in building design, construction and management. Through a single digital data repository, BIM shares and maintains an integrated digital representation of all building infor - mation throughout the entire project lifecycle (Gu and London, 2010). Creating a BIM ecosystem requires careful consideration for BIM-related products, processes and people to co-evolve (Gu, Singh and London, 2015). BIM supports powerful building data documentation and digitis - ation, and facilitates more effective com munication across different disciplines involved in the building lifecycle. It aims to break down the communication barriers among different stakeholders by maintaining only one consistent digital model for all disciplines through new processes of generating, managing and sharing building information. BIM research has been developed over decades and has largely addressed new building designs, while its applications on existing buildings are still under scrutiny (Volk, Stengel and Schultmann, 2014).
Historical BIM (HBIM) is a recent development of BIM focusing on historical buildings, and addresses the historical, cultural and social parameters that exist in this realm (Biagini et al. 2016; Quattrini, Pierdicca and Morbidoni, 2017). Most implementations of Historical BIM (HBIM) involve a parametric library, which is a collection of parametric geometries allowing mathematical modelling (through generations and variations) of shapes and objects, and a mapping system for capturing and translating survey data for heritage conservation (Maurice, McGovern and Sara, 2009), therefore it is also called ‘historic BIM’ or ‘heritage BIM’. HBIM extends the generic BIM approach to document and manage buildings that are historically important with significant heritage values. Because of this, most HBIM literature has focused on addressing the accurate, automated creation of a 3D digital model from survey data through advanced techniques such as terrestrial laser scanning and photogrammetry. Recent research developments on the translation of point clouds into building models is especially common in this domain (Baik, 2017; Chiabrando, Lo Turco and Rinaudo, 2017; Lopez et al., 2017).
Hospital workers are critical for a successful response to an infectious disease outbreak and for preventing disease transmission to the community. Therefore, hospital crisis management should implement efforts to improve hospital workers’ preparedness in responding to public health emergencies caused by infectious diseases. Traditionally, preparedness and skill of hospital workers have been emphasized, but awareness of the importance of the emotional mindset of hospital workers in dealing with disease outbreaks has only recently increased; therefore, empirical approaches to examining emotional responses of hospital workers has been limited. This study analyzed qualitative data of the 2015 Middle East Respiratory Syndrome outbreak in South Korea. In particular, negative emotions and stress experienced by hospital workers who treated patients were characterized, as were the events that triggered such experiences. These events were categorized into four themes (eg, Mistake, Missing, Delay Due to Communication Failure). Identifying events that trigger negative emotions in hospital workers has important implications for hospitals’ management guidance in relation to an infectious disease outbreak. (Disaster Med Public Health Preparedness. 2019;13:504-510)
Given its diverse disease courses and symptom presentations, multiple phenotype dimensions with different biological underpinnings are expected with bipolar disorders (BPs). In this study, we aimed to identify lifetime BP psychopathology dimensions. We also explored the differing associations with bipolar I (BP-I) and bipolar II (BP-II) disorders.
We included a total of 307 subjects with BPs in the analysis. For the factor analysis, we chose six variables related to clinical courses, 29 indicators covering lifetime symptoms of mood episodes, and 6 specific comorbid conditions. To determine the relationships among the identified phenotypic dimensions and their effects on differentiating BP subtypes, we applied structural equation modeling.
We selected a six-factor solution through scree plot, Velicer's minimum average partial test, and face validity evaluations; the six factors were cyclicity, depression, atypical vegetative symptoms, elation, psychotic/irritable mania, and comorbidity. In the path analysis, five factors excluding atypical vegetative symptoms were associated with one another. Cyclicity, depression, and comorbidity had positive associations, and they correlated negatively with psychotic/irritable mania; elation showed positive correlations with cyclicity and psychotic/irritable mania. Depression, cyclicity, and comorbidity were stronger in BP-II than in BP-I, and they contributed significantly to the distinction between the two disorders.
We identified six phenotype dimensions; in addition to symptom features of manic and depressive episodes, various comorbidities and high cyclicity constructed separate dimensions. Except for atypical vegetative symptoms, all factors showed a complex interdependency and played roles in discriminating BP-II from BP-I.
To critically evaluate the relevance of social exchange theory (SET) to the contemporary workplace, Chernyak-Hai and Rabenu (2018) point out a number of factors that reshape work relationships and suggest how to apply and extend social exchange theory to understand the new era work relationships. However, in their discussion, they focus mainly on reciprocal exchange (RE) in dyadic relationships. The discussion completely overlooks another important form of social exchange, namely, generalized exchange (GE), which is increasingly relevant to contemporary organizations exactly because of the changes indicated by Chernyak-Hai and Rabenu. In this commentary, we briefly review prior investigations into GE across various social science disciplines and then point out its increasing relevance to organizations. Finally, we will discuss implications for future research in the industrial and organizational (I-O) psychology literature.
The structure of polymer networks in hydrogels determines the properties. In this study, we investigated the structure of a charge-balanced polyampholyte, poly(4-vinylbenzenesulfonate-co-[3-(methacryloylamino) propyl] trimethylammonium chloride). From as-prepared samples, nanoscale globules were visualized in polyampholyte hydrogels for the first time. The impact of dialyses processes on polymer structures were also studied. In deionized water, salt ions are leached out, thus polymer chains undergo zipping process to form cellular structure with micrometer-thick polymer walls that allow mechanical toughness to the hydrogel. Samples dialyzed in 6 M potassium hydroxide solution did not show such cellular structure, as in the case of as-prepared samples.
Clonorchis sinensis (C. sinensis), a trematode parasite that invades the hypoxic hepatobiliary tract of vertebrate hosts requires a considerable amount of oxygen for its sexual reproduction and energy metabolism. However, little is known regarding the molecular mechanism of C. sinensis involved in the adaptation to the hypoxic environments. In this study, we investigated the molecular structures and induction patterns of hypoxia-inducible factor-1α (HIF-1α) and other basic helix–loop–helix and Per–Arnt–Sim (bHLH–PAS) domain-containing proteins such as HIF-1β, single-minded protein and aryl hydrocarbon receptor, which might prompt adaptive response to hypoxia, in C. sinensis. These proteins possessed various bHLH–PAS family-specific domains. Expression of C. sinensis HIF-1α (CsHIF-1α) was highly induced in worms which were either exposed to a hypoxic condition or co-incubated with human cholangiocytes. In addition to oxygen, nitric oxide and nitrite affected the CsHIF-1α expression depending on the surrounding oxygen concentration. Treatment using a prolyl hydroxylase-domain protein inhibitor under 20%-oxygen condition resulted in an increase in the CsHIF-1α level. Conversely, the other bHLH–PAS genes were less responsive to these exogenous stimuli. We suggest that nitrite and nitric oxide, as well as oxygen, coordinately involve in the regulation of HIF-1α expression to adapt to the hypoxic host environments in C. sinensis.
This report summarizes a recent study demonstrating simple and rapid synthesis of a new Al–Mg alloy system and ultimately synthesizing a metal matrix nanocomposite, which was achieved by processing stacked disks of the two dissimilar metals by conventional high-pressure torsion (HPT) processing. The synthesized Al–Mg alloy system exhibits exceptionally high hardness through rapid diffusion bonding and simultaneous nucleation of intermetallic phases with increased numbers of HPT turns through 20, and improved plasticity was demonstrated by increasing strain rate sensitivity in the alloy system after post-deformation annealing. An additional experiment demonstrated that the alternate stacking of high numbers of dissimilar metal disks may produce a faster metal mixture during HPT. Metal combinations of Al–Cu, Al–Fe, and Al–Ti were processed by the same HPT procedure from separate pure metals to examine the feasibility of the processing technique. The microstructural analysis confirmed the capability of HPT for the formation of heterostructures across the disk diameters in these processed alloy systems. The HPT processing demonstrates a considerable potential for the joining and bonding of dissimilar metals at room temperature and the expeditious fabrication of a wide range of new metal systems.