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An improved antenna array (AA) has beenintroduced, in which reverse-link synchronous transmissiontechnique (RLSTT) is incorporated to effectively make better anestimation of covariance matrices at a beamformer-RAKE receiver.While RLSTT is effective in the first finger at the RAKE receiverin order to reject multiple-access interference (MAI), thebeamformer estimates the desired user's complex weights,enhancing its signal and reducing cochannel interference (CCI)from the other directions. In this work, it is attempted toprovide a comprehensive analysis of user capacity which reflectsseveral important factors such as the shape of multipath intensityprofile (MIP), the number of antennas, and power control error(PCE). Theoretical analysis, confirmed by the simulations,demonstrates that the orthogonality provided by employing RLSTTalong with AA may make the DS-CDMAsystem insensitive to the PCE even with fewer numbers of antennas. [ABSTRACT FROM AUTHOR]

The characteristics of the earthquake motions at the base of a structure are affected by the properties of the underlying soil through the soil amplification and soil–structure interaction phenomena. In this paper the effect of nonlinear soil behavior on the elastic and inelastic response spectra of the motions that would be recorded at the free surface of a soft soil deposit or at the base of each structure is investigated. The analyses are conducted for a soil layer by itself and for a complete soil structure system using a finite element discretization of the soil in cylindrical coordinates and an approximate linear iterative procedure to simulate nonlinear behavior. Studies are conducted for structures, with a constant base and variable height modeled as equivalent linear or nonlinear single degree of freedom systems and an input motion at the base of the soil deposit representative of rock outcrop motions. Both mat and pile foundations are considered. The results illustrate clearly the importance of the nonlinear soil behavior. [ABSTRACT FROM AUTHOR]

We have developed a new atomic force microscope (AFM), with a z scanner independent of the xy scanner. Unlike conventional AFM systems, our xy scanner moves only the sample in the xy plane, while the z scanner controls the AFM probe along the z axis. The xy scanner is a single module parallel-kinematics flexure stage that guarantees high orthogonality and minimum out-of-plane motion. The z scanner is a one-dimensional flexure stage with negligible out-of-axis motion. Separating the z scanner from the xy scanner practically eliminates the x–z cross coupling problem inherent in conventional AFMs. Furthermore, the z servo response is no longer limited by the xy scanner characteristics, allowing us to make full use of our high performance z scanner. Our system uses the laser beam bounce detection method, and only the cantilever and the photodetector are mounted on the z scanner to realize a lightweight probing unit. We have devised a unique design such that the photodetector signal measures only the cantilever deflection and not the z-scanner motion. Our new AFM provides fast z servo response and high scan accuracy. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Although impaired endothelial function is well known in patients with diabetes mellitus (DM), the precise mechanism and the factors that contribute to this dysfunction remain to be clarified. The authors examined the effect of acute hyperglycemia on endothelium-dependent vasodilation in patients with DM or impaired glucose metabolism in vivo by plethysmography. In eight patients with diabetes mellitus or impaired glucose metabolism, the vasodilatory response to acetylcholine at infusion rates of 7.5, 15, and 30 μg/min was studied in the fasting state and at two levels of hyperglycemia, which were achieved by the infusion of glucose, insulin, and somatostatin. The vasodilatory response to acetycholine was measured by calculating the forearm blood flow ratio (FBFR), defined as the measured forearm blood flow at a specific acetylcholine infusion rate divided by the baseline forearm blood flow without acetylcholine infusion. The induction of hyperglycemia resulted in a significant reduction in FBFR for all rates of acetylcholine infusion. The FBFR at an acetycholine infusion rate of 7.5 μg/min was 1.13 ± 0.07 and 1.19 ± 0.06 for stages 1 and 2, respectively, compared with 1.36 ± 0.08 for stage 3 ( p < .05). In addition, at an acetycholine infusion rate of 30 μg/min, the reduction in FBFR was associated with the degree of hyperglycemia (3.72 ± 0.51, 2.98 ± 0.42, 2.42 ± 0.32 for stages 1, 2, and 3 glucose levels, respectively, at an acetylcholine infusion rate of 30 μg/min, p < .05 by analysis of variance [ANOVA]). The results show that the induction of hyperglycemia results in a significant attenuation of endothelial function, and suggests the importance of hyperglycemia in the development of endothelial dysfunction observed in patients with DM or impaired glucose metabolism. [ABSTRACT FROM AUTHOR]

Presents a theory of the short-circuit 1/f noise currents in semiconductor devices with one-dimensional geometry. Derivation of the noise current density equation under the number fluctuation model for 1/f noise; Experiments and discussion; Conclusion on the theory.

Enteropathy-type T-cell lymphoma (ETTL) is a rare disease with a poor prognosis. According to the World Health Organization (WHO) classification, it is a subtype of the peripheral T-cell lymphomas. This disease is associated with gluten-sensitive enteropathy, has a high risk of intestinal perforation and obstruction, and is refractory to chemotherapeutic treatment. We report the case of a 73-year-old woman who was diagnosed with enteropathy-type T-cell lymphoma of the small intestine, which was positive for the markers of cytotoxic T cells, CD3, CD8, and CD56, on immunohistochemical staining after resection of the perforated terminal ileum. [ABSTRACT FROM AUTHOR]

Core exchangeable polymer–silica hybrid capsules with solvent-selective permeability were fabricated, in which the internal silica layer, formed from pre-included precursors, has the role of a framework to prevent irreversible deformation of the hollow capsules. [ABSTRACT FROM AUTHOR]

The article discusses that overexpression of calbindin-D28K in hippocampal progenitor cells increases neuronal differentiation and neurite outgrowth. Calbindin d-siRNA blocks both endogeneous and overexpressed calbindin-d28K. Vitamin D3 induces caldinbin-D28K, neurite outgrowth, and neuronal differentiation.

This study explores the structure-property relationships in colorless polyimides (CPIs) synthesized from stereoisomeric (exo- and endo-form) alicyclic dianhydrides, combined with various diamines. The structural configurations of 5,5’-(1,4-phenylene)bis[hexahydro-(3aR,4R,5R,7S,7aS)-rel-4,7-Methanoisobenzofuran-1,3-dione] (BzDA-exo) and 5,5-(1,4-phenylene)bis(hexahydro-4,7-methanoisobenzofuran-1,3-dione) (BzDA-endo) were confirmed as exo- and endo-forms, respectively, through 1H NMR and 2D NOESY NMR analyses. Wide-angle X-ray scattering (WAXS) data revealed that stereoisomeric structures influence polymer chain packing in synthesized CPIs. The investigation extended to the chemical and physical structure-dependent properties such as physical, thermal and optical properties of the PIs. Notably, structure-dependent physical and thermal properties were evident, with a particularly strong structure-property relationship manifesting in the coloration and yellow index (Y.I.) of PIs. These systematic characterizations offer profound insights into the design and optimization of chemical and physical structures in CPIs, highlighting the versatility of stereoisomeric monomers for various applications.

Abstract Despite the proposal of numerous advanced materials for batteries, there remains a notable lack of comprehensive assessment protocols that facilitate direct comparisons between laboratory-scale research and industrial trials. Here, we introduce a standardized method coined as extremely lean electrolytic testing (ELET), designed as a uniform framework for evaluating the performance across different battery systems. This approach replicates the cycling behaviour of larger pouch cells within the more manageable format of coin cells under ELET conditions. Employing ELET, we develop quantitative models to create contour maps that standardize cell performance metrics. To demonstrate the ELET efficacy, we explore the mitigation of electrolyte decomposition in lithium-ion batteries through applying polydopamine coatings on silicon/carbon composite anodes, achieving a 150% decrease in electrolyte decomposition compared to uncoated ones. Additionally, we employ the ELET method to compare the performance of various post-secondary and commercial batteries, demonstrating its full utility in battery evaluation.

The article presents a case of a 35-yea-old nurse with pruritic, erythematous patches in both of her hands and her forearms. The lesion developed two days following her contact with Augmentin® dry syrup and distilled water. The patient's patch tests results and her clinical history showed that the allergic contact dermatitis was due to clavulanic acid in the Augmentin®. The authors recommended that nurse to avoid contact with clavulanic acid.

Abstract The battery‐like systems utilizing redox materials present a promising avenue for electrochemical desalination with reduced energy consumption. However, several attempts have focused on reducing the operational voltage to minimize energy consumption, and efforts to enhance the performance of such systems as energy storage devices remain limited. Herein, a system with a high energy density capable of sustaining freshwater production was proposed. Furthermore, in this proposed system, the electrolytes with different pH values were utilized to implement an operational voltage of 2 V or higher. Accordingly, an alkaline Zn electrolyte was paired with acidic MnO2 or VOSO4 electrolyte. During the process, potential side reactions such as chlorine evolution and proton crossover were not observed, even without water‐splitting reactions. Ultimately, at operational voltages exceeding 2 V, the system achieved a desalination rate of 0.104 mg/cm2/min and demonstrated maximum energy discharge of up to 2.4 Wh/L. These designed systems pave the way towards a more environmentally friendly and efficient approach to desalination.

Rechargeable aqueous Zn–CO2 battery is a promising technology that combines energy storage and CO2 utilization to meet the needs of sustainable and eco–friendly energy. However, the practical application of this technology is hindered by factors such as the low current density, low Faradaic efficiency of value–added products, high overpotential, and limited cycles. Cathode catalysts, which are crucial components, significantly influence the performance of the system. There have been several updated publications on cathode materials for aqueous Zn–CO2 batteries, but there are few reports of high–performance Zn–CO2 batteries. Herein, a new system for achieving high performance by injecting gas–phase CO2 was reported. Unlike conventional Zn–CO2 batteries, the problem of low CO2 solubility was overcome by injecting gaseous CO2. The designed Zn–gaseous CO2 battery, powered by Ag or Au catalysts, achieved that Faradaic efficiencies of CO were 92.72 % and 89.56 % at 4 mA/cm2, respectively. The maximum power density of 5.52 mW/cm2 and 7.89 mW/cm2 for Ag and Au catalysts, respectively, were obtained, which were much larger than the power density of conventional aqueous Zn–CO2 batteries. In addition, using X–ray diffraction, ex–situ monitoring of the reaction characterizations on Ag and Au cathodes was carried out and the durability of 600 min was achieved, when using Au cathode. These results offer a practical way to design a Zn–CO2 battery for high-performance energy storage and CO2 utilization.

Purpose This study analyzes the characteristics and prognosis of patients with de novo and recurrent metastatic gastric cancers. Methods This retrospective study included 301 advanced, pathologically confirmed gastric cancer patients who received palliative chemotherapy between 2012 and 2022. The de novo cohort included patients who presented with distant metastasis at diagnosis, and the recurrent metastatic cohort was composed of patients with metastasis after curative gastrectomy. We analyzed prognostic association by Cox regression and compared survival time of both cohorts using the Kaplan-Meier survival analysis. Results The study included 167 de novo and 112 recurrent patients. No differences were noted among the patients with de novo disease and recurrent metastatic disease concerning age, sex, Eastern Cooperative Oncology Group scores, primary cancer location, and pathologic features. Patients in the recurrent group versus the de novo group had a longer duration of chemotherapy (1.16±1.18 years vs. 0.85±0.84 years, P= 0.01) and lower mean body mass index (20.22±2.78 kg/m2 vs. 21.93±3.38 kg/m2, P< 0.001). The median overall survival in the de novo group was 11.6 versus 14.4 months in the recurrent group (P= 0.02). Conclusion De novo and recurrent metastatic gastric cancer are characterized by distinct subpopulations. Advanced gastric cancer patients with recurrence have significantly better survival versus those in the de novo cohort. The differences between de novo and recurrent gastric cancer patient outcomes could facilitate discussions about the selection of the clinical trial of each patient and help with their personalized treatment.

The effluent limitations of wastewaters discharged from various industrial facilities are based on uniform regulatory criteria in Korea. However, an individual effluent limitation on each effluent discharging industry is widely applicable for regulation of industrial wastewater in the USA and European Union (EU). The main objectives of this study were; (1) to suggest the method and procedure for establishing effluent limitations for the petroleum refining facilities on the basis of treatment technology to implement the most appropriate effluent limitations reflecting wastewater characteristics and the level of treatment technologies and (2) to estimate the effluent limitations based on the Best Practicable Control Technology (BPT) currently available. To decide an individual effluent limitation, Technology-Based Effluent Limitation (TBEL) was derived for the petroleum refining industry based on BPT in this study. It was suggested that effluent limitations were BOD5 5.0mg/L, CODMn 11.0mg/L, SS 4.0mg/L, TN 7.0mg/L, and TP 0.3mg/L and BPT for the petroleum refining facilities in Korea was oil separation, coagulation and floatation, activated sludge treatment, and sand filter (or activate carbon filter). In order to implement new effluent limitations and BPT suggested in this study, institutional complements of separate effluent limitations for individ- ual industrial sectors are urgently required in Korea. [ABSTRACT FROM AUTHOR]

Abstract Silicon has garnered significant attention as a promising anode material for high‐energy density Li‐ion batteries. However, Si can be easily pulverized during cycling, which results in the loss of electrical contact and ultimately shortens battery lifetime. Therefore, the Si anode binder is developed to dissipate the enormous mechanical stress of the Si anode with enhanced mechanical properties. However, the interfacial stability between the Si anode binder and Cu current collector should also be improved. Here, a multifunctional thiourea polymer network (TUPN) is proposed as the Si anode binder. The TUPN binder provides the structural integrity of the Si anode with excellent tensile strength and resilience due to the epoxy‐amine and silanol‐epoxy covalent cross‐linking, while exhibiting high extensibility from the random coil chains with the hydrogen bonds of thiourea, oligoether, and isocyanurate moieties. Furthermore, the robust TUPN binder enhances the interfacial stability between the Si anode and current collector by forming a physical interaction. Finally, the facilitated Li‐ion transport and improved electrolyte wettability are realized due to the polar oligoether, thiourea, and isocyanurate moieties, respectively. The concept of this work is to highlight providing directions for the design of polymer binders for next‐generation batteries.

This study presents a systematic investigation of miscibility, rheological, and physical/optical properties of polycarbonate (PC)/poly (methyl methacrylate-co-phenyl methacrylate) (PMMA-co-PPhMA) blends with varying copolymer composition and blend weight percentage (wt%). Herein, single glass transition behavior from miscible blends was confirmed through differential scanning calorimetry (DSC) and dynamic mechanical analyzer (DMA), while further analysis revealed differences in blend homogeneity. X-ray scattering and rheometer measurements complemented this different phase homogeneity in the blends. PMMA-co-PPhMA with 14 mol% of PhMA (denoted as PMPA-2) demonstrated the most favorable miscibility and phase homogeneity among the prepared blends. Enhanced scratch resistance was achieved by increasing the wt% of PMMA-co-PPhMA, but phase inhomogeneity resulted in decreased optical transparency. The blend between PC and PMPA-2 exhibited optimal rheological, mechanical, and optical properties. This study provides insights into the PC-based blend materials for applications in various industrial fields.

A facile approach is proposed to improve the anisotropic heat conduction of polyimide composite films containing hexagonal boron nitride (h-BN), thermally conductive filler with high anisotropy, via surface hybridization with ferrofluids as magnetic carrier source. The surfaces of the h-BNs were decorated with Fe3O4 particles to control their alignment using magnetic field. The h-BNs with hydroxyl groups (f-BN) were mixed with ferrofluids and heated to 130 °C with stirring. A considerable amount of Fe3O4 nanoparticles was attached to the surface of f-BNs, named mf-BNs. Flexible polyimide (PI) composite films were prepared by adding mf-BNs at 1–30 wt.% to investigate the anisotropic alignment of mf-BNs under magnetic field. The thru-plane thermal conductivity of the PI composite film with vertically aligned mf-BN of 30 wt.% is 6 times higher than that of the neat PI film, as increased from 0.212 to 1.246 W/m∙K. This result is attributed to the anisotropic h-BN particles coated with the magnetic fluid arranged within the PI matrix in the vertical direction by using a neodymium magnet with less than 150 mT. This can solve the thermal issues of next-generation electronics by speeding the vertical heat transfer, which can greatly contribute to the improvement of the device reliability.

This study revealed that the synthesis of effective flow modifiers using diamine monomers and fatty acid reduces the melt viscosity of polyamide 66 (PA66) composites. Moreover, the study provided insights into the rheological and mechanical properties of these reinforced polymers. In particular, the oligomers hexamethylenediamide, dodecamethylene diamide, 4,4′-methylenebis(cyclohexylamide) (i.e., HMDA, DMDA, MCHA) to modify the PA66 were prepared from hexamethylenediamine, dodecamethylene diamine, 4,4′-methylenebis(cyclohexylamine). The synthesized modifiers showed thermal stability in the PA66 processing temperature. Further, the chemical similarity increased due to amide bonds in the backbone of the flow modifiers, showing good compatibility with PA66. Additionally, PA66/glass fiber (GF) composites containing the flow modifier showed enhanced rheological and mechanical properties. The flow modifiers significantly improved the tensile strength and flexural modulus of the PA66/GF composites. The proposed synthetic method is straightforward, opening up a new strategy for reducing the melt viscosity of PA66 without degradation of the mechanical properties. The method improves the compatibility of the PA66/GF composites even in high amounts of GF, achieving effective polymer processing for practical applications.

With the growing demand for soft robots capable of various degrees of locomotion based on reversibly actuating liquid crystalline networks (LCNs), the fabrication of complex 3D architectures from 2D LCN films via shape reconfiguration and/or assembly techniques are studied recently. However, once a system is formed and fixed into a specific 3D structure, only certain movements can be implemented using the fixed structure, and disassembly into the original 2D films is challenging. Therefore, studies to overcome this irreversible fabrication process become increasingly important. Herein, an effective and simple preparation of static and dynamic covalent dual‐cross‐linked, photo‐controllable LCN (pc‐LCN) films as building blocks for lego‐like, monolithically assembled 3D soft transformable robots is presented. By tailoring the static and dynamic covalent linkages in the networks, pc‐LCN films can be readily reconfigured and assembled into complex 3D structures under ultraviolet (UV) irradiation. Such monoliths can also be disassembled into their constituent building block films and reassembled into different architectures under the same UV stimulation. Moreover, by adopting selective visible‐light‐responsive dopant dyes to actuate pc‐LCN building blocks, 3D soft transformable robots with versatile motion capabilities, including rolling, gripping, and cargo transport in multiple directions, are demonstrated.

Abstract The three-dimensional field-in-field (3-D FIF) technique for radiotherapy is an advanced, state-of-the-art method that uses multileaf collimators to generate a homogeneous and conformal dose distribution via segmental subfields. The purpose of this study is to evaluate the dosimetric reproducibility of 3-D FIF plans using the original simulation computed tomography (iCT) scans and re-simulation CT (rCT) scans for whole breast irradiation (WBI) schedule. This study enrolled a total of 34 patients. The study population underwent iCT scans for standard WBI and took rCT scans after 45 Gy of WBI for cone down boost plans. The dosimetric parameters (V105%, V103%, V100%, V98%, V95%, V90%, V50%), plan quality indices (conformity index, homogeneity index) and clinical parameters (isocenter-breast axis, isocenter-lung axis, soft tissue volumes within radiation field, lung volumes within radiation field) were assessed. The median time interval from surgery to iCT was 33 days and from iCT to rCT was 35 days. All dosimetric parameters exhibited statistically significant differences between iCT and rCT among cohorts with a surgery-iCT interval of

Background/Aims We evaluated the efficacy of docetaxel and epirubicin as neoadjuvant chemotherapy in locally advanced breast cancer and assessed the predictive factors for response to neoadjuvant chemotherapy and prognostic factors related to relapse-free survival. Methods Forty patients who received docetaxel and epirubicinas neoadjuvant chemotherapy for locally advanced breast cancer were evaluated retrospectively. Neoadjuvant chemotherapy consisted of intravenous injection of 75 mg/m2 docetaxel and 60 mg/m2 epirubucin on day 1, every 21 days, and two to six cycles. Results Twenty-five (62.5%) patients showed a partial response, and 15 (37.5%) patients showed a stable disease in the first response evaluation after two or three cycles of neoadjuvant chemotherapy. In the second response evaluation of nine patients who received six cycles of neoadjuvant chemotherapy, one patient achieved a complete response, but two patients with hormone receptor-negative, human epidermal growth factor receptor 2-positive breast cancer experienced disease progression. Twenty-five (62.5%) patients experienced downstaging after neoadjuvant chemotherapy. Patients with > 20% pretreatment Ki-67 and decrease of Ki-67 between pre- and post-neoadjuvant chemotherapy showed a trend for better response. In multivariate analysis, advanced pathological stage showed a significant negative effect on relapse-free survival. Conclusions Docetaxel and epirubicin neoadjuvant chemotherapy showed a good response in locally advanced breast cancer. Pretreatment Ki-67 and change of Ki-67 may play a role as predictive factor for response to neoadjuvant chemotherapy.

Abstract Vitrimers have shown advantages over conventional thermosets via capabilities of dynamic network rearrangement to endow repairability as well as recyclability. Based on such characteristics, vitrimers have been studied and have shown promises as a 3D printing ink material that can be recycled with the purpose of waste reduction. However, despite the brilliant approaches, there still remain limitations regarding requirement of new reagents for recycling the materials or reprintability issues. Here, a new class of a 4D printable vitrimer that is translated from a commercial poly(ε‐caprolactone) (PCL) resin is reported to exhibit self‐healability, weldability, reprocessability, as well as reprintability. Thus, formed 3D‐printed vitrimer products show superior heat resistance in comparison to commercial PCL prints, and can be repeatedly reprocessed or reprinted via filament extrusion and a handheld fused deposition modeling (FDM)‐based 3D printing method. Furthermore, incorporation of semicrystalline PCL renders capabilities of shape memory for 4D printing applications, and as far as it is known, such demonstration of FDM 3D‐printed shape memory vitrimers has not been realized yet. It is envisioned that this work can fuel advancement in 4D printing industries by suggesting a new material candidate with all‐rounded capabilities with minimized environmental challenges.

Zoonotic avian influenza viruses pose severe health threats to humans. Of several viral subtypes reported, the low pathogenic avian influenza H7N9 virus has since February 2013 caused more than 1,500 cases of human infection with an almost 40% case-fatality rate. Vaccination of poultry appears to reduce human infections. However, the emergence of highly pathogenic strains has increased concerns about H7N9 pandemics. To develop an efficacious H7N9 human vaccine, we designed vaccine viruses by changing the patterns of N-linked glycosylation (NLG) on the viral hemagglutinin (HA) protein based on evolutionary patterns of H7 HA NLG changes. Notably, a virus in which 2 NLG modifications were added to HA showed higher growth rates in cell culture and elicited more cross-reactive antibodies than did other vaccine viruses with no change in the viral antigenicity. Developed into an inactivated vaccine formulation, the vaccine virus with 2 HA NLG additions exhibited much better protective efficacy against lethal viral challenge in mice than did a vaccine candidate with wild-type (WT) HA by reducing viral replication in the lungs. In a ferret model, the 2 NLG-added vaccine viruses also induced hemagglutination-inhibiting antibodies and significantly suppressed viral replication in the upper and lower respiratory tracts compared with the WT HA vaccines. In a mode of action study, the HA NLG modification appeared to increase HA protein contents incorporated into viral particles, which would be successfully translated to improve vaccine efficacy. These results suggest the strong potential of HA NLG modifications in designing avian influenza vaccines.

The electronic signature service has been causing various problems due to the rapid growth of e-commerce services. Therefore, in order to create an authentication service suitable for the era of the 4th Industrial Revolution, new security authentication technologies such as the cloud must be utilized. However, there is a lack of prior management studies on the intention to accept digital signatures. Therefore, this study conducted an empirical study to identify factors affecting the intention to adopt cloud-based digital signature services. This research proposed a model based on the technology–organization–environment framework and empirically analyzed the degree of mutual causality and influence between variables using the partial least squares structural equation model. The results show that technical characteristics, organizational characteristics, and environmental characteristics significantly affected the intention to adopt. However, there are still many concerns about the security of cloud-based services. It has been confirmed that solving this problem is the key to the activation of the electronic signature service.

Aim: To investigate the clinical characteristics of left primary epiploic appendagitis and to compare them with those of left colonic diverticulitis., Methods: We retrospectively reviewed the clinical records and radiologic images of the patients who presented with left-sided acute abdominal pain and had computer tomography (CT) performed at the time of presentation showing radiological signs of left primary epiploic appendagitis (PEA) or left acute colonic diverticulitis (ACD) between January 2001 and December 2011. A total of 53 consecutive patients were enrolled and evaluated. We also compared the clinical characteristics, laboratory findings, treatments, and clinical results of left PEA with those of left ACD., Results: Twenty-eight patients and twenty-five patients were diagnosed with symptomatic left PEA and ACD, respectively. The patients with left PEA had focal abdominal tenderness on the left lower quadrant (82.1%). On CT examination, most (89.3%) of the patients with left PEA were found to have an oval fatty mass with a hyperattenuated ring sign. In cases of left ACD, the patients presented with a more diffuse abdominal tenderness throughout the left side (52.0% vs 14.3%; P = 0.003). The patients with left ACD had fever and rebound tenderness more often than those with left PEA (40.0% vs 7.1%, P = 0.004; 52.0% vs 14.3%, P = 0.003, respectively). Laboratory abnormalities such as leukocytosis were also more frequently observed in left ACD (52.0% vs 15.4%, P = 0.006)., Conclusion: If patients have left-sided localized abdominal pain without associated symptoms or laboratory abnormalities, clinicians should suspect the diagnosis of PEA and consider a CT scan.