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Squarylium-based colorimetric hydrogen sulfide (H2S) chemosensors (SQ1, SQ2, and SQ3) were developed, and their detection properties were systematically characterized. SQ1 exhibited rapid and high resolution H2S sensing properties through significant color changes detectable by naked-eye with limit of detection as low as 7.2 ppb. SQ1 also showed excellent selectivity for H2S detection over other relevant anions and nucleophiles. Sensing mechanisms of SQ1 were investigated based on spectroscopic and 1H NMR analyses with quantum calculations. Furthermore, SQ1 showed an efficient response to H2S under versatile conditions in the solution, solid, and dyed fabric states, which suggests applicability of SQ1 to simple, low-cost, and practical H2S sensors.

In this paper, we consider multi-user signal transmission by means of zero-forcing (ZF) beamforming with an aid of user grouping in spatially correlated massive antenna environments. For the user grouping, we exploit transmission performance loss (TPL) due to nulling out inter-user interference. We partition users into a number of groups so that users in each group experience low TPL. We transmit user signal in each group by means of ZF beamforming, while allocating transmission resource to user groups in an orthogonal manner. Finally, we verify the performance of the proposed scheme by computer simulation.

The proposed study describes the development of a carbon nanotube (CNT)-based gas sensor capable of detecting the presence of hydrogen (H2) gas at room temperature. CNT yarn used in the proposed sensor was fabricated from synthesized CNT arrays. Subsequently, the yarn was treated by means of a simple one-step procedure, called acid treatment, to facilitate removal of impurities from the yarn surface and forming functional species. To verify the proposed sensor’s effectiveness with regard to detection of H2 gas at room temperature, acid-treated CNT and pure yarns were fabricated and tested under identical conditions. Corresponding results demonstrate that compared to the untreated CNT yarn, the acid-treated CNT yarn exhibits higher sensitivity to the presence of H2 gas at room temperature. Additionally, the acid-treated CNT yarn was observed to demonstrate excellent selectivity pertaining to H2 gas.

Germ cell tumours (GCTs) are one of the most threatening malignancies in young men and women. Although several reports have suggested the importance of OCT4 in human GCTs, its role has not been clearly investigated on a molecular level. In this study, we revealed GCT-specific direct transcriptional target genes of OCT4. Conditional knockdown of OCT4 in GCT cell lines reduced cell proliferation by affecting both cell cycle and death. Knockdown of OCT4 also reduced stemness of GCTs, as assessed by the expression of other stemness factors, alkaline phosphatase staining, and tumour sphere formation ability. Analysis of whole mRNA expression patterns among GCT cells harbouring endogenous, depleted, and rescued OCT4 revealed 1133 OCT4 target genes in GCT. Combined analysis of both the chromatin binding signature of OCT4 and the genes whose expression levels were changed by OCT4 revealed 258 direct target genes of OCT4 in GCTs. In a similar way, 594 direct target genes in normal embryonic stem cells (ESCs) were identified. Among these two sets of OCT4 direct target genes, 38 genes were common between GCTs and ESCs, most of which were related to regulation of pluripotency, and 220 genes were specific to GCTs, most of which were related to focal adhesion and extracellular matrix organisation. These results provide a molecular basis for how OCT4 regulates GCT stemness and will aid our understanding of the role of OCT4 in other cancers.

Introduction: In the background of the increased suicide rate in the second decade of life, analysis of the characteristics of poisoning-related attempted suicide in adolescents and evaluation of the differences from adults may form an important basis for establishing measures to prevent deaths from poisoning. Objective: We aimed to investigate the types of toxic substances ingested for attempted suicide by poisoning in adolescents admitted to the emergency department (ED). Method: This cross-sectional study retrospectively analyzed and investigated the medical records of patients aged 13 or older, admitted to the ED of a tertiary medical institute over a period of 3 years, for attempted suicide by poisoning. Results: The psychiatric diagnoses among patients in the adolescent group included depression (75.8%), bipolar disorder (12.5%), and panic disorder (12.5%). In terms of the type of drug used for poisoning, antidepressants or anti-psychotics and sleeping pills were the most commonly used in the adolescent (43 subjects, 45.2%) and adult (286 subjects, 37.6%) groups, respectively. Conclusion: As there is a higher chance of poisoning by easily accessible drugs, the emergency physician needs to investigate any preceding diagnoses of psychiatric or medical illnesses in the adolescent patients attempting suicide with unknown drugs.

This study investigated patterns of probable posttraumatic stress disorder (PTSD) and their predictors among 2,431 Asian American and 31,455 non-Hispanic White World Trade Center (WTC) Registry participants 2-3 years and 5-6 years after the WTC attack. Participants were divided into four PTSD pattern groups: resilient, remitted, delayed onset, and chronic. Asians had a lower proportion in the resilient group (76.5% vs. 79.8%), a higher proportion in the chronic (8.6% vs. 7.4%) and remitted (5.9% vs. 3.4%) groups, and a similar proportion in the delayed onset group (about 9%) compared to Whites. In multinomial logistic regression analyses, disaster exposure, immigrant status, lower income, pre-attack depression/anxiety, and lower respiratory symptoms were associated with increased odds of chronic and delayed onset PTSD (vs. resilience) among both races. Education and employment were protective against chronic and delayed onset PTSD among Whites only. These results can inform targeted outreach efforts to enhance prevention and treatment for Asians affected by future events.

Carton clamp truck is widely perceived as the high-efficient handling equipment of factory premises and warehouse by its capability of palletless handling. Therefore, the significance of a lab- based handling simulation is becoming higher with the growth of clamp truck usage. In this study, preliminary FEA and design of handling test courses for the lab-based simulation of carton clamp truck handling were performed, and the PSD analyses were performed for the modified one for the test course proposed by Park et al. (2017) as well as ASTM D 6055 and ISTA 3B standards. For the vibration in all directions, the vibration energy intensity analyzed by ISTA 3B standard showed higher than that by the other two cases. A FEA was performed for the handling operation of the sudden stop of the clamps after lifting the target HCP (heavyweight refrigerator corrugated package, w=180 kgf) up to the specified height. The slip distance between the clamp arm and the target HCP was 0.85 mm. The simulation result of 0.85 mm was 3.7 times lower than the experimental result (3.2 mm) obtained by Park et al. (2017), and it was estimated that the deviation comes from both the experimental error by weight imbalance of target HCP, and excessive simplification during the FE modelling of target HCP.

A series of earthquake events give impetus to research on the ductile fracture behavior of steel materials. In the last decades, many fracture models have been developed and utilized in the mechanical or aerospace engineering. Nevertheless, very little application to structural members used in the construction industry has been made due to the lack of a suitable model for the fracture behavior of constructional steel. This paper presents the experimental and finite element (FE) technique to predict ductile fracture in mild carbon structural steel (SS275) sheets, which has been widely used in building structures. The post-necking true stress–strain responses were successfully estimated using the weighted-average method. The Bao and Wierzbicki (BW) model, which requires only two model parameters, was selected for the identification of fracture locus. Each model parameter was calibrated from uniaxial tension and in-plane shear specimens with the aid of digital image correlation (DIC) and finite element analysis. Fracture simulation was then performed and validated based on the experimental results of the specimens under combined tension and shear stress state.

Conventional channel estimation schemes may require for the transmission of orthogonal pilot signal for each antenna in frequency-division duplex (FDD) transmission systems. It is of great concern to get channel information with an affordable signaling overhead in FDD massive multi-input multi-output (m-MIMO) transmission environments. The signaling overhead for the channel estimation can be reduced by exploiting the channel correlation matrix (CCM) of m-MIMO channel. When the m-MIMO channel is correlated in spatial domain, the channel information can be estimated with reduced pilot signaling overhead. However, the estimation performance may seriously be affected by the accuracy of CCM. In this paper, we investigate the effect of CCM accuracy on the m-MIMO channel estimation and verify it by computer simulation.

A planetary gearbox is one of the most important components in rotating machinery. In construction equipment, it is mainly used for swing and traveling devices due to huge torque capability and good torque transmission. Unexpected failure of the planetary gearbox can cause increased idle time, unnecessary cost due to inability of the construction site and safety hazards such as an operator isolation in a remote area. For these reasons, the need for timely prediction of unexpected failure becomes increasingly important in the field of construction machinery. In general, studies on fault diagnosis and condition monitoring of planetary gearboxes have been carried out in fields such as aircraft, wind-turbines and power plants. Researches in the above-mentioned fields usually require high performance computing power, and the burden of cost for diagnosis is relatively small. In addition, construction machinery also faces difficulties due to various uncertainties such as uncertain operating conditions that affect the vibration characteristics of gearboxes. This study focuses on an approach to the vibration-based fault diagnosis methodology that can distinguish gear faults in a planetary gearbox in an excavator using vehicle-based test. First, we analyze the types of gear faults and the parts where failures occur mainly through the database of field failures. From this result, several fault types to be used in the experiment are selected, and an arbitrary fault is applied to gears. Secondly, since the vibration data is acquired directly from the excavator, the signal processing method that can remove the noise as much as possible and distinguish the fault is selected. Finally, optimized features are selected to minimize the uncertainty impacts that cannot be eliminated or unknown. Through this study, we confirmed the effect of the signal processing method which can be used in the planetary gearbox of the excavator as follows: 1) Several kinds of fault can be distinguished. 2) Faults and methodologies that can be distinguished in the constant speed condition 3) Faults and methodologies that can be distinguished in the transition speed condition.

Explosions and fire have very critical safety hazard impacts on offshore oil and gas facilities since they are mostly located in remote areas and could induce serious environmental issues. Explosion risk assessment and structure blast analysis are essential for these production facilities, and research studies have been carried out. Explosion due to blowout during drilling operation is also a critical risk for drilling units, and this has not been researched much until the accident of the drilling unit in the Gulf of Mexico in 2010. This paper provides the risk and evaluation of explosion and structure under blast pressure during the drilling operation, whereas previous research studies have mainly been interested in process plants. This study suggests weight saving in drilling units through the consideration of the actual behavior of gas explosion. Weight saving is the priority of offshore unit design due to payload. This research also gives guidelines to select the material-grade-appropriate anti-explosion system through the comparison of several materials by design and result.

The explosion of a building generates plenty of debris that flies far away. The flying debris is hazardous because it contains large amounts of kinetic energy. Therefore, determining the safety distance from the debris is essential. However, debris ricochet that collides onto the ground affects the safety distance because the ricochet phenomenon is influenced by the condition of the medium. In this study, experiments and finite element analysis were performed to investigate the ricochet based on the water content of sand. From a direct shear test, the internal friction angle and cohesion of sand were obtained based on the water content. The effects of internal friction angle and adhesion on the yield stress and ricochet were investigated. The results indicated that as the water content increased, the internal friction angle increased and then decreased, and the cohesion continued to decrease. The yield stress was proportional to the internal friction angle and inversely proportional to adhesion. Therefore, lower yield stress resulted in deeper penetration of debris, leading to higher energy loss, which increased the kinetic energy loss factor. Thus, the condition of the medium should be considered for setting a proper safety distance suitable for the surrounding environment of the building.

A common approach for dynamic analysis in current practice is based on a discrete time-integration scheme. This approach can be largely attributed to the absence of a true variational framework for initial value problems. To resolve this problem, a new stationary variational principle was recently established for single-degree-of-freedom oscillating systems using mixed variables, fractional derivatives and convolutions of convolutions. In this mixed convolved action, all the governing differential equations and initial conditions are recovered from the stationarity of a single functional action. Thus, the entire description of linear elastic dynamical systems is encapsulated. For its practical application to structural dynamics, this variational formalism is systemically extended to linear elastic multidegree- of-freedom systems in this study, and a corresponding weak form is numerically implemented via a quadratic temporal finite element method. The developed numerical method is symplectic and unconditionally stable with respect to a time step for the underlying conservative system. For the forced-damped vibration, a three-story shear building is used as an example to investigate the performance of the developed numerical method, which provides accurate results with good convergence characteristics.

Objective Bitter taste receptors (TAS2Rs) are expressed in the extraoral tissues, where they possess various physiological functions. This study is to characterize TAS2Rs expression in normal and allergic nasal mucosa and analyse nasal symptom after challenge with bitter tastes to evaluate their pathophysiological function in normal and allergic nasal mucosa. Methods The expression levels of TAS2Rs (TAS2R4, 5, 7, 10, 14, 39, and 43) in nasal mucosa were investigated by real-time PCR, Western blot, and immunohistochemistry. The expression levels of TAS2Rs and Ca(2+) imaging in cultured epithelial cells were measured after stimulation with type 2 cytokines (IL-4, IL-5, and IL-13) or bitter tastes. Nasal symptoms in control subjects and allergic rhinitis patients using visual analogue score and acoustic rhinometry were evaluated before and after stimulation with bitter tastes. Vascular diameter of rat nasal septum was measured before and after treatment with bitter tastes. Results TAS2Rs tested here were expressed in nasal mucosa where they were commonly distributed in superficial epithelium, submucosal glands, and endothelium. Their expression levels are increased in allergic nasal mucosa and up-regulated in cultured epithelial cells simulated with type 2 cytokines. After treatment with bitter tastes, intracellular Ca(2+) signalling was increased in cultured epithelial cells, and vascular constriction was found in rat nasal septum. Increased nasal patency was observed in human nasal mucosa without pain or sneezing. Conclusion and clinical relevance TAS2Rs are constitutively expressed in human nasal mucosa and their expression levels are increased in allergic nasal mucosa, where they could potentially contribute to shrinkage of normal and allergic nasal mucosa.

The purpose of this study is to analyze the relations of innovation and productivity following the introduction of ICT and the effects in the process of innovative investments activity-innovation-productivity, not only by finding causes and effects. For this purpose we conducted surveys of SMEs classified into 7 categories by type of business. To put it concretely, this study was performed to find out the foactors which allow companies to secure competitiveness by enhancing of innovative measures through ICT, and to further analyze the political implications for the development of small and medium-size business by conducting an empirical analysis of the process, from the determination of innovative investments all the way through to production. Analysis model used CDM model using econometric methods such as multiple regression analysis and multinominal logit analysis to produce results. Also we established and analyzed models of innovation investment determinants, innovation determinants and productivity determinants to analyze specifically the relations between ICT and productivity.

Recently, in order to overcome the key shortcoming in Hamilton’s principle, the extended framework of Hamilton’s principle was formulated. This new variational framework provides a sound base to develop novel temporal finite element methods with the proper use of initial conditions to the strong form. As its initial and practical application in structural dynamic analysis, this paper presents a quadratic temporal finite element method for linear elastic multi-degrees-of-freedom systems. Numerical features of the developed method are analytically and numerically investigated with comparison to the currently dominant method; the results highlight the improved performance of the proposed method.

Simple Summary Octamer-binding transcription factor 4 (OCT4) plays an important role in early embryonic development, but is rarely expressed in adults. However, in many cancer cells, this gene is re-expressed, making the cancer malignant. This present study revealed that inhibiting OCT4 transcriptional activity induces cancer cell differentiation and growth retardation. Specifically, when the phosphorylation of OCT4 serine 236 increases by interfering with the binding of protein phosphatase 1 (PP1) to OCT4, OCT4 loses its transcriptional activity and cancer cells differentiate. Therefore, this study presents the basis for the development of protein-protein interaction inhibitors that inhibit the binding of OCT4 and PP1 for cancer treatment. Abstract Octamer-binding transcription factor 4 (Oct4) plays an important role in maintaining pluripotency in embryonic stem cells and is closely related to the malignancies of various cancers. Although posttranslational modifications of Oct4 have been widely studied, most of these have not yet been fully characterized, especially in cancer. In this study, we investigated the role of phosphorylation of serine 236 of OCT4 [OCT4 (S236)] in human germ cell tumors (GCTs). OCT4 was phosphorylated at S236 in a cell cycle-dependent manner in a patient sample and GCT cell lines. The substitution of endogenous OCT4 by a mimic of phosphorylated OCT4 with a serine-to-aspartate mutation at S236 (S236D) resulted in tumor cell differentiation, growth retardation, and inhibition of tumor sphere formation. GCT cells expressing OCT4 S236D instead of endogenous OCT4 were similar to cells with OCT4 depletion at the mRNA transcript level as well as in the phenotype. OCT4 S236D also induced tumor cell differentiation and growth retardation in mouse xenograft experiments. Inhibition of protein phosphatase 1 by chemicals or short hairpin RNAs increased phosphorylation at OCT4 (S236) and resulted in the differentiation of GCTs. These results reveal the role of OCT4 (S236) phosphorylation in GCTs and suggest a new strategy for suppressing OCT4 in cancer.

Wearable sensors for tracking human body motion are being increasingly applied in medical systems and are considered important components of human–machine interfaces. This study proposes a flexible sandwich-like capacitive pressure sensor that consists of carbon nanotube–polydimethylsiloxane (CNT–PDMS) composite electrodes and a porous polymer dielectric layer. CNT yarn and polymer materials help fabricate a pressure sensor without complex patterns, easily and quickly. The dielectric layer is made of a porous polymer to improve the sensor sensitivity. The high porosity of the dielectric layer increases its deformation under pressure and enhances the sensitivity (to approximately 5.6 kPa−1 (%)) even under low pressures ( Owing to the high porosity of the dielectric layer and flexibility of the CNT yarn, the capacitive pressure sensor proposed in this study exhibits good performance in detecting even a slight change in stimulus. The proposed pressure sensor can be applied in wearable applications such as human-friendly interfaces and sensitive electronic skins.

Temozolomide is the current first-line treatment for glioblastoma patients but, because many patients are resistant to it, there is an urgent need to develop antitumor agents to treat temozolomide-resistant glioblastoma. Gossypol, a natural polyphenolic compound, has been studied as a monotherapy or combination therapy for the treatment of glioblastoma. The combination of gossypol and temozolomide has been shown to inhibit glioblastoma, but it is not clear yet whether gossypol alone can suppress temozolomide-resistant glioblastoma. We find that gossypol suppresses the growth of temozolomide-resistant glioblastoma cells in both tumor sphere and adherent culture conditions, with tumor spheres showing the greatest sensitivity. Molecular docking and binding energy calculations show that gossypol has a similar affinity to the Bcl2 (B-cell lymphoma 2) family of proteins and several dehydrogenases. Gossypol reduces mitochondrial membrane potential and cellular ATP levels before cell death, which suggests that gossypol inhibits several dehydrogenases in the cell&rsquo, s metabolic pathway. Treatment with a Bcl2 inhibitor does not fully explain the effect of gossypol on glioblastoma. Overall, this study demonstrates that gossypol can suppress temozolomide-resistant glioblastoma and will be helpful for the refinement of gossypol treatments by elucidating some of the molecular mechanisms of gossypol in glioblastoma.

A thermal convection-based accelerometer was fabricated, and its characteristics were analyzed in this study. To understand the thermal convection of the accelerometer, the Grashof and Prandtl number equations were analyzed. This study conducted experiments to improve not only the sensitivity, but also the frequency band. An accelerometer with a more voluminous cavity showed better sensitivity. In addition, when the accelerometer used a gas medium with a large density and small viscosity, its sensitivity also improved. On the other hand, the accelerometer with a narrow volume cavity that used a gas medium with a small density and large thermal diffusivity displayed a larger frequency band. In particular, this paper focused on a Z-axis response to extend the performance of the accelerometer.

A small moving cell (SMC) system is proposed to be a potential system in the next-generation cellular system. However, it is challenging issue to provide wireless backhaul links to the SMCs which may have high mobility. In this paper, we propose statistical beamforming (SBF) technique to provide the wireless backhaul links in massive MIMO systems. Unlike most of the conventional SBF schemes, we consider multiple antennas at the receiver side where the base station (BS) needs to determine the proper number of SBF beams. We first determines candidates of SBF beams as eigenvectors corresponding to dominant eigenvalues of channel correlation matrix (CCM). The average achievable SINR can be estimated using a Monte-Carlo sampling process without ST-CSI at the BS, then the proper beams and the transmit powers are adjusted by iterative water-filling algorithm. The simulation results show that the proposed SBF scheme is quite feasible for the wireless backhaul of SMCs in high mobility without the feedback of short-term channel information.

Internal short circuit of a lithium polymer battery (4.6 Ah capacity and 4.30 V charging voltage) with a ceramic-coated separator has been investigated by infrared measurement during nail penetration. The surface temperatures at nail penetration area and battery body were simultaneously measured by infrared camera and, as a result, three different failure modes have been proposed. The battery with 100% of SOC experiences thermal runaway phenomenon by means of the second internal short circuit. The batteries with low SOC (0% and 50% of SOC) were also investigated to identify the phenomena occurred in SOC 100% battery (the second internal short circuit), but neither fire nor explosion in the battery with low SOC was observed. The analysis of burr status after nail penetration demonstrates that it is quite important factor related to the failure modes. The results of this study can be applied to the design of safe battery.

Summary Objectives Maximal extrathyroidal extension (ETE) is known to be an important prognostic factor in papillary thyroid carcinoma (PTC). However, the significance of minimal ETE is controversial. The aim of this study was to investigate the clinicopathologic characteristics and prognostic significance of minimal vs maximal ETE in PTC. Materials and methods A group of 967 patients who underwent thyroidectomy for PTC in a tertiary hospital between January 2000 and December 2011 were studied retrospectively. Patients were classified into three groups: absence of ETE, and minimal and maximal ETE. The minimal ETE group was further categorized into two subgroups according to invasion of strap muscles or no invasion (STI+ and STI−). Results Gender did not differ between the three groups of patients. The mean age of the patients with maximal ETE was significantly higher than in those belonging to the other groups. Tumor size, bilaterality, lymph node metastasis and stage increased significantly according to the degree of ETE. Recurrence and survival rates did not differ between the absence and minimal ETE groups, or between the STI− and STI+ subgroups of minimal ETE. However, the maximal ETE group had significantly higher recurrence and lower survival rates than the other groups (P Conclusion Maximal ETE is a significant factor for poor prognosis. However, minimal ETE is not associated with increased recurrence or decreased survival in patients with PTC.

Si-Ti-Ni alloy (STN) is a promising active material for lithium ion batteries with high coulombic efficiency and stable cycleability since inactive matrix plays an important role in buffer action against large volume changes of Si during charge/discharge reactions. However, there still remain several challenges to apply to electric vehicles due to capacity fading and unstable cycle performances at high current density. In this study, to improve the properties of STN, we modified the surface of STN with poly(3,4-ethylenedioxythiophene) (PEDOT) by in-situ polymerization. The modified STN provides many advantages including stable cycleability, low charge transfer resistance, strong adhesion between active materials and active material and current collector, etc. Electrochemical performances are significantly improved after modification; especially under high current density conditions.

As the development of structural system and material enable to construct many high-rise buildings. However, high rise buildings are vulnerable to the strong wind rather than seismic excitation, because they have relatively long period. Recently, intensity and frequency of extreme wind such as hurricane and typhoon have been increased with the weather change all over the world. Therefore, in this study, 50-story building with three types of braces which are diagonal brace, X-brace, Chevron brace are modelled and compared with non-braced 50-story building by changing wind speed. Finally, all the results from four cases are compared for wind performances. As a result, buildings reinforced with X-brace and Chevron braces have a good performance subjected to the strong wind.

The areal capacity ratio of negative to positive electrodes (N/P ratio) is the most important factor to design the lithium ion batteries with high performance in the consideration of balanced electrochemical reactions. In this study, the effect of N/P ratio (1.10, 1.20, and 1.30) on electrochemical properties has been investigated with a lithium polymer battery with PVdF-coated separator and 1.40 Ah of capacity. The N/P ratio is controlled by adjusting the anode thickness with a fixed anode density. The cell with an N/P ratio higher than 1.10 effectively suppresses the lithium plating at the 0.85C-rate charging at 25 °C and the cell with 1.20 of N/P ratio shows the enhanced cycle performance in comparison with other cells. Among the cells with differently designed N/P ratios, significant difference was not observed in the aging test with fully charged batteries at 25 and 45 °C. The effect of N/P ratio on electrochemical properties of lithium batteries can help to design the safe full cell without lithium plating.

In order to test the performance of a cannonball, various types of media are used in a test site. The best media should have good stability, effectiveness, economic feasibility, etc. Among them, sand is most widely used. Sand, which consists of many small grains, can be used effectively in a site. In this study, the penetration depth of a cannonball is analyzed for shear modulus using FEM. It is found that the penetration depth decreases with the shear modulus of sand. For management of a test side, the shear modulus of sand is an important factor.

As extension of the previous two-surface model in plasticity, a two-surface model for viscoplasticity is presented herein. In order to validate and investigate the performance of the proposed model, several numerical simulations are undertaken especially for structural steel under monotonic and cyclic loading cases, where experimental results and numerical results from the rate dependent kinematic hardening model are also provided for the reference. For all the cases studied, the proposed model can appropriately account for the rate-effects in both maximum stress and hysteretic shapes.

A radiographic analysis with scoliosis patients.To analyze correlations between sagittal spinal alignment and coronal scoliotic curvature.Sagittal spinal alignment and scoliosis may have a significant relationship, and schematic analysis is needed.The study group was comprised of 163 patients with adolescent idiopathic scoliosis. Subjects underwent anteroposterior and lateral radiographs of the whole spine including hip joints. The radiographic parameters used were magnitude, location and direction of curve, thoracic kyphosis, thoracolumbar kyphosis, lumbar lordosis, sagittal balance, sacral slope, and pelvic angle. Subjects were classified into 4 groups according to the severity of coronal curvature: Cobb angle ≤20 degrees, Cobb angle 21-40 degrees, Cobb angle 41-60 degrees, and Cobb angle60 degrees. In addition, subjects were divided into 4 subgroups according to Roussouly's classification (types 1-4) of sagittal spinal shape. Schematic analysis was performed to determine the relationship between coronal and sagittal parameters.Analysis of parameters with severity of coronal curvature, thoracic kyphosis, and sacral slope were significantly higher in high-grade scoliosis (P0.05). However, the pelvic angle was higher in low-grade scoliosis, and sagittal balance showed a significantly higher positive value in low-grade scoliosis (P0.05). In the analysis of sagittal spinal shapes, Roussouly groups 3 and 4 showed more severe scoliosis with higher lumbar lordosis and thoracic kyphosis (P0.05). In addition, Roussouly group 1 demonstrated a significantly higher incidence of low-grade scoliosis, whereas groups 3 and 4 had a higher incidence of high-degree scoliosis by cross-relation analysis (P0.05).A significant relationship exists between sagittal spinal shape and coronal curvature in scoliosis. Understanding the biplanar shapes of scoliosis may be helpful to the surgeons.

Conventional channel estimation schemes may require for the use of orthogonal pilot signals for each antenna in frequency-division duplex (FDD) wireless systems. It is a very challenging issue to get channel information with an affordable signaling overhead in massive multi-input multi-output (m-MIMO) FDD transmission environments. The signaling overhead for the channel estimation can be reduced by exploiting the downlink channel correlation matrix (DCCM) of m-MIMO channel. With the use of DCCM, the channel information can be estimated using a reduced number of pilot signals. However, the accuracy of DCCM may seriously affect the estimation performance. In this paper, we consider the estimation of DCCM in m-MIMO transmission environments. Since the distance between a base station and a user is much larger than that between antennas, a set of antenna pairs of equal distance may experience similar spatial correlation due to the far-field effect. We consider the estimation of DCCM by averaging the correlation of these antenna pairs without reception of a large number of pilot signals, significantly reducing the pilot signaling overhead. We also consider the improvement of estimated DCCM by dropping out inaccurate correlation terms. Finally, we verify the proposed scheme by computer simulation.