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Primary tumour size (PTS) is known to be a significant prognostic factor in patients with papillary thyroid carcinoma (PTC) undergoing thyroidectomy. Although cutoff values of 2 and 4 cm are widely used in surgical extent decision and long-term outcomes predictions, the effectiveness of arbitrary cutoff values in stratifying patients for target outcomes is questionable. This study aimed to determine new optimal cutoffs of PTS.Patients (n = 529) with PTC who underwent total thyroidectomy were retrospectively reviewed. After risk factor analysis for structural recurrence, the optimal cutoffs of PTS were automatically calculated using restricted cubic spline analysis and X-tile software. Subgroups were classified based on the newly determined cutoff values. Both the recurrence-free survival (RFS) and the proportion of patients in each response-to-therapy category, using the dynamic risk stratification system (DRS), were compared between the subgroups.PTS was confirmed as an independent risk factor for structural recurrence. The optimal cutoff values were calculated as 1.4 and 3.0 cm. The subgroups stratified using these newly determined cutoffs showed significantly different RFS and DRS based on the response to initial therapy, but the subgroups classified using the cutoffs of 2 and 4 cm did not.The newly determined cutoff values of PTS may be useful in better stratifying patients with PTC undergoing thyroidectomy for target outcomes and can be considered as a new definition in staging and risk stratification systems.

Self-extubation can lead to detrimental outcomes for the patient. Complications that result from self-extubation range from laryngeal injury, respiratory distress, arrhythmia, pneumonia, to even death. With respect to patient safety, not only is prevention of self-extubation one of the most important goals in all intensive care units around the world, but also it is one of the most common mishaps in the area of intensive care. Since self-extubation and consequent re-intubation are unexpected events, they can embarrass the medical staff and negatively affect the treatment choice, and consequently, require other invasive procedures that may not have been necessary. The most important thing for patients exposed to self-extubation is to keep in mind the presence of airway damage, which can be confirmed through our experience as described here, through repeated re-intubations and eventually tracheostomy.

Background: Lymph node (LN)-related risk factors have been updated to predict long-term outcomes in patients with papillary thyroid carcinoma (PTC). However, those factors’ analytic appropriateness and general applicability must be validated. This study aimed to assess LN-related risk factors, and suggest new LN-related risk categories. Methods: This multicenter observational cohort study included 1232 patients with PTC with N1 disease treated with a total thyroidectomy and neck dissection followed by radioactive iodine remnant ablation. Results: The median follow-up duration was 117 months. In the follow-up period, structural recurrence occurred in 225 patients (18.3%). Among LN-related variables, the presence of extranodal extension (p < 0.001), the maximal diameter of metastatic LN foci (p = 0.029), the number of retrieved LNs (p = 0.003), the number of metastatic LNs (p = 0.003), and the metastatic LN ratio (p < 0.001) were independent risk factors for structural recurrence. Since these factors showed a nonlinear association with the hazard ratio of recurrence-free survival (RFS) rates, we calculated their optimal cutoff values using the K-means clustering algorithm, selecting 0.2 cm and 1.1 cm for the maximal diameter of metastatic LN foci, 4 and 13 for the number of metastatic LN, and 0.28 and 0.58 for the metastatic LN ratio. The RFS curves of each subgroup classified by these newly determined cutoff values showed significant differences (p < 0.001). Each LN risk group also showed significantly different RFS rates from the others (p < 0.001). Conclusions: In PTC patients with an N1 classification, our novel LN-related risk estimates may help predict long-term outcomes and design postoperative management and follow-up strategies. After further validation studies based on independent datasets, these risk categories might be considered when redefining risk stratification or staging systems.

We present the intra- and inter-molecular organocatalysis of SN2 fluorination using CsF by crown ether to estimate the efficacy of the promoter and to elucidate the reaction mechanism. The yields of intramolecular SN2 fluorination of the veratrole substrates are measured to be very small (&lt, 1% in 12 h) in the absence of crown ether promoters, whereas the SN2 fluorination of the substrate possessing a crown ether unit proceeds to near completion (~99%) in 12 h. We also studied the efficacy of intermolecular rate acceleration by an independent promoter 18-crown-6 for comparison. We find that the fluorinating yield of a veratrole substrate (leaving group = −OMs) in the presence of 18-crown-6 follows the almost identical kinetic course as that of intramolecular SN2 fluorination, indicating the mechanistic similarity of intra- and inter-molecular organocatalysis of the crown ether for SN2 fluorination. The calculated relative Gibbs free energies of activation for these reactions, in which the crown ether units act as Lewis base promoters for SN2 fluorination, are in excellent agreement with the experimentally measured yields of fluorination. The role of the metal salt CsF is briefly discussed in terms of whether it reacts as a contact ion pair or as a “free” nucleophile F−.

Long-term management and follow-up strategies in patients with intermediate-risk papillary thyroid carcinoma (PTC) according to the American Thyroid Association (ATA) are still controversial due to the paucity of data on unique risk factors or a risk stratification system predictive of long-term outcomes.This study included 649 patients with PTC who underwent an initial surgical treatment. Retrospectively enrolled patients were categorized according to the ATA risk stratification system. Intermediate-risk patients were further categorized into subgroups by the number of ATA intermediate risk factors. The recurrence-free survival (RFS) rates of these subgroups were compared with those of low- and high-risk patient groups. Additionally, the patients were classified according to their response to the initial therapy using the dynamic risk stratification (DRS) system, and the percentages of patients in each category were compared among the subgroups.The median follow-up period was 102 months. Structural recurrence occurred in 9.2% of all enrolled patients (60/649) and in 13.0% of intermediate-risk patients (40/308). Patients with two or more current intermediate risk factors had a poorer RFS than patients with only one risk factor (p 0.001) and showed a comparable RFS to high-risk patients (p 0.050). The percentages of patients with an excellent response category for DRS significantly decreased with an increase in the number of intermediate risk factors.Subclassification according to the number of intermediate risk factors may be useful to better predict the RFS and the response to initial therapy in patients with intermediate-risk PTC.

Most blunt renal injuries (BRIs) are managed conservatively without complications. Because conservative management with observation (CMO) is widely conducted, failed CMO is frequent. Clarifying the role and indication of CMO is important to manage BRI patients. Therefore, this study was conducted to analyse factors related to failed CMO.BRI patients (aged13 years) who were admitted via the emergency department in Wonju Severance Christian Hospital were analysed retrospectively between January 2008 and July 2020. Patient characteristics, including clinical data, laboratory findings, transfusion requirements, injury grade, initial CT findings, length of hospital stay, intensive care unit stay, and mortality, were investigated for all enrolled patients.Kidney injury grade ≥ 4, perinephric haematoma rim distance (PHD), length of main laceration, intravascular contrast extravasation (ICE), Gerota's fascia discontinuity, multiple lacerations, dissociated renal fragment and complexity of laceration were statistically significantly different between the successful CMO and failed CMO groups in the comparative analysis. The multivariate analysis showed that perinephric haematoma rim distance [odds ratio (OR) 1.44 [95% confidence interval (CI) 1.09 - 1.90], p = 0.011] and ICE [OR 7.41 (95% CI 2.20 - 24.99), p = 0.001] were mutually independent risk factors associated with failed CMO. When the ROC curve of PHD and ICE was generated to predict the failure of CMO, the area under the curve (AUC) was 0.884 (95% CI, 0.826 - 0.942), p0.001), and the optimal cut-off value for PHD was 2.9 cm, and for ICE was presence of ICE on CT [sensitivity: 90.5% (95% CI, 0.70 - 0.99), specificity: 78.0% (95% CI, 0.73 - 0.83)].PHD and ICE may be useful factors to predict failed CMO for BRI patients. PHD2.9 cm and the presence of ICE may indicate who will require invasive procedures. Close observation is wise for patients with these risk factors.

연료비용은 항공사 전체 운영비용에서 상당한 부분을 차지하고 있어 연료비용 절감을 위한 연료절감 노력은 항공사 수익역량 강화를 위해 필요하며, 전 지구적인 기후변화 대응 및 이산화탄소 배출량 감소는 항공부문에서도 큰 도전 과제가 되어가고 있다. 항공산업에 있어 연료절감과 기후변화 대응을 위한 기술적인 방법은 동일하다고 할 수 있어 다양한 방법이 시도되고 있으나, 무조건적인 항공산업 규모의 줄임이 아닌 효율성 있는 운영을 통해 전체적인 산업 발전을 도모함이 유익하다고 본다. 이를 위해 연료효율성을 수송 단위 당 연료효율로 측정함은 이상적이나, 기존 지수에는 여러 제약이 있다는 문헌 연구 결과, 본 논문에서는 새로운 “연료 효율성 지수”를 제시하였고, 이를 종속변수로 하는 “연료효율성 예측 모델”을 수립하였다. 각 독립변수의 회귀계수를 살펴봄으로써, 개별 인자가 연료효율성에 미치는 영향력 확인을 통해 항공사는 연료비용 절감 및 탄소저감 활동에 참조할 수 있다.

Purpose Traumatic kidney injury can be treated surgically or nonsurgically. Nonsurgical treatment options include angiography, embolization, and conservative treatment. We aimed to identify factors that help in making clinical decisions on treatment plans for patients with traumatic kidney injury caused by blunt trauma. Methods The study included 377 patients aged ≥18 years with traumatic kidney injury caused by blunt abdominal trauma admitted to the emergency room of Wonju Severance Christian Hospital between January 2008 and July 2020. Medical records, laboratory test results, and computed tomography results were retrospectively reviewed. Results Multivariable logistic analysis showed diastolic blood pressure at admission and disruption of Gerota's fascia were significantly associated with surgical treatment, and that perinephric hematoma rim distance was the only significant indicator favoring embolization. Receiver operating characteristic curve analysis showed that angiography and embolization should be considered when hematoma size exceeds 2.97 cm. Conclusion When a patient with traumatic kidney injury due to blunt trauma visits an emergency room, even when vital signs are stable, Gerota's fascia should be checked by computed tomography prior to deciding on surgical treatment, and angiographic embolization should be considered if perinephric hematoma rim distance exceeds 2.97 cm.

A graphite grid was fabricated using reactive ion etching with a stencil mask. The graphite film was synthesized through chemical vapor deposition on commercial Ni foil and was simply etched with a stencil mask using oxygen plasma during reactive ion etching. It had ∼85% optical transmittance at a 550-nm wavelength and ∼120 Ω/sq sheet resistance. Graphite grids placed on a human hand used to distinguish its motions showed high strain-sensing performance: its gauge factor ranged from 100 to 350, and its response times for strain loading and for release were short (10 and 80 ms, respectively). Because the graphite-based structures could be prepared in large quantities and because etching with a reusable stencil mask is very simple, mass production of high-performance motion sensors using the well-structured graphite grid is commercially feasible.

To investigate the relations between coronal mass ejection (CME) speed and magnetic field properties measured in the photospheric surface of CME source regions, we selected 22 disk CMEs in the rising and early maximum phases of the current Solar Cycle 24. For the CME speed, we used two-dimensional (2D) projected speed observed by the Large Angle and Spectroscopic Coronagraph onboard the Solar and Heliospheric Observatory (SOHO/LASCO), as well as a 3D speed calculated from the triangulation method using multi-point observations. Two magnetic parameters of CME source regions were considered: the average of magnetic helicity injection rate and the total unsigned magnetic flux. We then classified the selected CMEs into two groups, showing: i) a monotonically increasing pattern with one sign of helicity (group A: 16 CMEs) and ii) a pattern of significant helicity injection followed by its sign reversal (group B: 6 CMEs). We found that: 1) 3D speed generally shows better correlations with the magnetic parameters than the 2D speed for 22 CME events in Solar Cycle 24; 2) 2D speed and the magnetic parameters of 22 CME events in this solar cycle have lower values than those of 47 CME events in Solar Cycle 23; 3) all events of group B in Solar Cycle 24 occur only after the beginning of the maximum phase, a trend well consistent with that shown in Solar Cycle 23; 4) the 2D speed and the helicity parameter of group B events continue to increase in the declining phase of Solar Cycle 23, while those of group A events abruptly decrease in the same period. Our results indicate that the two CME groups have a different tendency in the solar cycle variations of CME speed and the helicity parameters. Active regions that show a complex helicity evolution pattern tend to appear in the maximum and declining phases, while active regions with a relatively simple helicity evolution pattern appear throughout the whole solar cycle.

A new and simple method to prepare three-dimensional (3D) graphene foams is developed. It uses 3D Ni nanowire foams as a catalyst for chemical vapor deposition (CVD). Ni nanowires were synthesized on a large scale by the reduction of Ni ions under an applied magnetic field, and then assembled into a 3D film by filtrating a bulk Ni nanowire solution or by pressing Ni nanowire powder. An additional CVD process was conducted to develop graphene on the 3D Ni nanowire foam at 670 °C, which is considerably lower than the conventional growth temperatures of around 1000 °C. The resulting 3D graphene exhibited higher electrical conductivity (17.5 S/cm) as well as a higher specific surface area (145 m2/g) due to its highly dense and interconnected structure, with pores on the order of several microns. The 3D graphene foam also exhibited excellent electrical and mechanical properties under repeated mechanical deformations (stretching, bending and folding), demonstrating their potential for use in such applications as the electrodes in wearable devices and electrochemical catalysts.

We demonstrate a PMMA reverse transfer method, where a PMMA/graphene bilayer was reversely transferred onto target substrates, to better control both contamination and crack formation relative to conventional approaches. Based on this novel transfer process, the graphene sheet resistance was greatly reduced by about 50% at the same transmittance, exhibiting ∼200% higher efficiency when applied in a solar cell as the anode.

Purpose: The aim of the present study was to analyze the peri- and post-operative and oncologic outcomes for ascending colon cancer after complete mesocolic excision (CME) with central vessel ligation (CVL). Materials and methods: The data of 156 patients who underwent CME with CVL for ascending colon cancer between January 2000 and December 2011 were retrieved from a prospective database. Results: The median follow-up time was 63.6 months. The mean operation time was 191.6 min. The mean blood loss was 85.6 ml. The mean length of the hospital stay was 13.9 days. The mean number of total harvested lymph nodes was 30.3. A 5-year cancer-specific survival (CSS) rate was seen in 83.0% of patients, and a 5-year diseasefree survival (DFS) rate was seen in 79.7%. In stage I, the DFS and CSS rates were both 100%. In stage II, the DFS rate was 91.0% and the CSS rate was 92.3%. In stage III, the DFS rate was 53.5% and the CSS rate was 59.5%. In stage IIIa, the DFS and CSS rates were both 100%. In stage IIIb, the DFS rate was 70.1% and the CSS rate was 92.1%. In stag e IIIc, the DFS rate was 19.4% and the CSS rate was 44.0% (p

We describe the mechanism of graphene fluorination by XeF2, calculated here by a periodic plane-wave DFT. We find that the fluorination of graphene proceeds by simultaneous bonding of two F atoms from XeF2 via transition states that interact a bit asymmetrically with the graphene surface. The fluorination of graphene occurs at the (1, 4) positions of the constituent phenyl ring, eventually covering 25% of the graphene C atoms. Bonding to other positions involves large reaction barriers. We also elucidate the origin of experimental observations (Robinson, J. T.; et al. Nano Lett.2010, 10, 3001) of 100% saturation with F when both sides are allowed to react with XeF2. We find that fluorination at one side facilitates the bonding of F at the (1, 2) position on the other side of graphene by significantly lowering the activation barrier of fluorination, indicating that successive (1, 2) additions eventually lead to 100% coverage of graphene by F. We also discuss the effects of a defect on the graphene surface,...

Power supply represents a critical challenge in the development of body-integrated electronic technologies. Although recent research establishes an impressive variety of options in energy storage (batteries and supercapacitors) and generation (triboelectric, piezoelectric, thermoelectric, and photovoltaic devices), the modest electrical performance and/or the absence of soft, biocompatible mechanical properties limit their practical use. The results presented here form the basis of soft, skin-compatible means for efficient photovoltaic generation and high-capacity storage of electrical power using dual-junction, compound semiconductor solar cells and chip-scale, rechargeable lithium-ion batteries, respectively. Miniaturized components, deformable interconnects, optimized array layouts, and dual-composition elastomer substrates, superstrates, and encapsulation layers represent key features. Systematic studies of the materials and mechanics identify optimized designs, including unusual configurations that exploit a folded, multilayer construct to improve the functional density without adversely affecting the soft, stretchable characteristics. System-level examples exploit such technologies in fully wireless sensors for precision skin thermography, with capabilities in continuous data logging and local processing, validated through demonstrations on volunteer subjects in various realistic scenarios.

(M = metal, X = nucleophile) in organicsolvents are extremely sluggish because of the strongCoulombic influence of the metal cation on the nucleo-phile. Various schemes were employed to separate thenucleophile from the metal cation, but even strong basessuch as the crown ether are not very good for that purpose.Ionic liquids and molten salts

We present density functional theory (DFT) and time-dependent DFT (TD-DFT) study of the structures and electronic spectra of small CdSe nanocluster-adenine complexes Cd(n)Se(n)-adenine (n = 3, 6, 10, 13). We examine the changes in the geometries and excitation spectra of the nanoclusters induced by DNA base-binding. By comparing the results calculated for the bare (Cd(n)Se(n)), hydrogen-passivated (Cd(n)Se(n)H(2n)), as well as the corresponding adenine (Ade)-bound clusters (Cd(n)Se(n)-Ade, Cd(n)Se(n)H(2n)-Ade, Cd(n)Se(n)H(2n-2)-Ade), we find that binding with Ade slightly blue-shifts (up to 0.18 eV) the electronic excitations of bare nanoclusters but strongly red-shifts (1.2 eV) those of hydrogen-passivated nanoclusters. Natural bond orbital analysis shows that the LUMO of Cd(n)Se(n)H(2n)-Ade is a pi* orbital located on the purine ring.

We present calculations for the mechanism of S(N)2 reactions in ethylene glycol, focusing on the role of two protic functional groups (-OH) in the solvent molecule. We find that some hydroxyl groups act as Lewis base to interact with the cation, whereas others affect the reaction as Lewis acid to the nucleophile. We predict that the nucleophile (F-) reacts as an ion pair rather than as a solvent-separated ion when metal cation (Cs+) is used as a counterion. The overall influence of ethylene glycol manifests itself as the reaction barrier (E(double dagger) = 20.0, G(353K)(double dagger) = 21.5 kcal/mol) that is a bit smaller than that in tert-butyl alcohol, which proved to be a very efficient solvent for S(N)2 reactions [Kim, D. W., et al. J. Am. Chem. Soc. 2006, 128, 16394]. We therefore show that a small protic solvent such as ethylene glycol may be as efficient as a bulky alcohol for S(N)2 reactions.

We describe a highly efficient method for fabricating a variety of complex 3D nano-patterns from a single master pattern using secondary sputtering lithography, which is a 10 nm scale patterning method that we have developed. A rapid etching rate in the bottom part of the PS pillar during the RIE process can produce various nanostructure shapes and the PS residual layer thickness can influence various feature dimensions, due to the controlled RIE time leading to different PS layer thicknesses. This technique provides a highly effective method for producing various complex 3D patterns from a single master pattern. Thus, this method can serve as a new procedure for the cost-effective mass production of complex nanoscale patterns with high resolution.

We present calculations for Lys-(H(2)O)(n) (n = 2, 3) to examine the effects of microsolvating water on the relative stability of the zwitterionic vs canonical forms of Lys. We calculate the structures, energies, and Gibbs free energies of the conformers at the B3LYP/6-311++G(d,p), wB97XD/6-311++G(d,p), and MP2/aug-cc-pvdz levels of theory, finding that three water molecules are required to stabilize the Lys zwitterion. By calculating the barriers of the canonical ↔ zwitterionic pathways of Lys-(H(2)O)(3) conformers, we suggest that both forms of Lys-(H(2)O)(3) may be observed in low temperature gas phase.

We present calculations for the Arg-H2O system and predict that the zwitterionic Arg is thermodynamically more stable than the canonical form in the gas phase under the influence of a single water molecule because of the strongly basic guanidine side chain. Canonical conformers of Arg-H2O are found to isomerize to the zwitterionic forms via a small barrier (approximately 6 kcal/mol).