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The mechanical design of the fuel assembly of a sodium cooled fast reactor is presented in this paper. This is one of the design works of a prototype generation IV sodium cooled fast reactor (PGSFR), which is planned to be built in Korea. Among the design tasks of the fuel assembly, the normal operation conditions is primarily considered here. One of the main issues is the lack of an applicable design code because the currently available worldwide codes such as the ASME Section III Division 5 and RCC-MRx do not incorporate the material (HT-9, the ferriticmartensitic steel) of the fuel assembly’s structural components. To resolve this, the formulae of the yield and ultimate strengths of HT-9 are used here, which have been verified through comparing with the existing data in the references other than the codes. From this, we conservatively set up new design criteria and stress limits. Two fuel assemblies of different locations in the reactor core are chosen for the analysis. The results show that the stresses are far below the stress limits. In addition, a brittle fracture of the components is concerned considering the low temperature below the ductile-brittle transition temperature of the HT-9 during handling a fuel assembly in the reactor. It is found that the crack sizes that can cause a fracture failure are much larger than what can be detected using a normal non-destructive test method. Thus, it is soundly concluded that the presently designed PGSFR fuel assembly has sufficient structural integrity during normal operation and refuelling outage.

Numerical simulation of film condensation in a vertical downward channel flow is performed by employing the sharp-interface level-set method which can accurately implement the saturation temperature and phase-change mass flux conditions at the liquid-vapor interface. An analytical model for the internal film condensation is also developed by including the effect of vapor flow in the classical Nusselt model. The numerical results for film condensation in the laminar regime show good agreement with the analytical solutions. The level-set method is applied to investigate the effects of vapor velocity and wall temperature on the condensate film thickness and heat flux in the laminar and wavy regimes.

Background and objective Diabetes and hypertension are two prevalent and related chronic conditions. To inform the design and development of mobile health applications (mHealth apps) for people living with multiple chronic conditions, this paper examines features mentioned in developers’ descriptions and user reviews of mHealth apps, along with users’ attitudes toward associated features. Materials and methods Eleven top apps for diabetes and hypertension were identified from Google Play as of January 2020. Based on a stratified sampling strategy, 1,100 user reviews were selected to form the final dataset. Developers’ descriptions were also collected for analysis. Using the grounded theory approach, we developed a feature-oriented coding scheme, which was used to identify three levels of features mentioned in app descriptions and user reviews: feature group (the highest level), feature type (the second level), and individual feature (the lowest level). Users’ attitudes toward app features mentioned in user reviews were also analyzed. Results Most top-rated apps for diabetes and hypertension under study were multifeatured, incorporating self-management, information sharing, and decision support features. At the feature-group level, most informative user reviews commented on features related to self-management, followed by decision support and information sharing. The four most frequently mentioned feature types were data entry, data export/import, data visualization, and assessment. Users expressed overwhelming positive attitudes toward app features across all feature categories. Based on users’ assessments of existing features and requests for additional features, design implications for app development are provided. Conclusions Despite the diversity of app features provided by mHealth apps and users’ primarily positive attitudes toward existing app features, more comprehensive and personalized features are expected by app users to satisfy their health needs. Beyond identifying app features in user reviews, future research may seek more in-depth feedback from real-life patients for app development and design using methods like interviews and focus groups, to further enhance the overall quality of relevant mHealth apps to better support users.

Choroidal neovascularization (CNV) is the defining characteristic feature of the wet subtype of age-related macular degeneration (AMD) and may result in irreversible blindness. Based on anti-vascular endothelial growth factor (anti-VEGF), the current therapeutic approaches to CNV are fraught with difficulties, and mammalian target of rapamycin (mTOR) has recently been proposed as a possible therapeutic target, although few studies have been conducted. Here, we show that a recombinant adeno-associated virus-delivered mTOR-inhibiting short hairpin RNA (rAAV-mTOR shRNA), which blocks the activity of both mTOR complex 1 and 2, represents a promising therapeutic approach for the treatment of CNV. Eight-week-old male C57/B6 mice were treated with the short hairpin RNA (shRNA) after generating CNV lesions in the eyes via laser photocoagulation. The recombinant adeno-associated virus (rAAV) delivery vehicle was able to effectively transduce cells in the inner retina, and significantly fewer inflammatory cells and less extensive CNV were observed in the animals treated with rAAV-mTOR shRNA when compared with control- and rAAV-scrambled shRNA-treated groups. Presumably related to the reduction of CNV, increased autophagy was detected in CNV lesions treated with rAAV-mTOR shRNA, whereas significantly fewer apoptotic cells detected in the outer nuclear layer around the CNV indicate that mTOR inhibition may also have neuroprotective effects. Taken together, these results demonstrate the therapeutic potential of mTOR inhibition, resulting from rAAV-mTOR shRNA activity, in the treatment of AMD-related CNV. Keywords: retinal neovascularization, choroidal neovascularization, adeno-associated virus, mTOR, RNA interference, mTOR shRNA, autophagy

Recently, there have been many demands for flexible and wearable electronic devices; this has resulted in comparable numbers of demands for flexible rechargeable batteries as a power source. In this study, we propose a carbon-coated SnS nanosheet on flexible carbon foam composite materials as anodes for Li- and Na-ion batteries. To fabricate the flexible electrode, we first carbonized a piece of melamine foam under an inert atmosphere. Then, SnS nanosheets were precipitated onto the foam using a simple solvothermal method. Finally, thin carbon coating layers were formed to further enhance the electrochemical properties as electrodes. The materials were characterized with X-ray diffraction; electron microscopy; and Raman and X-ray photoelectron spectroscopies. The formation of SnS nanosheets and carbon coating layers was confirmed. An electrochemical test demonstrated that a high reversible capacity of 747 mAh g−1 was maintained after 100 cycles in Li-ion cells and a capacity of 318 mAh g−1 was obtained after 50 cycles in Na-ion cells with good rate capabilities. The results could be attributed to microstructure design with carbon foam to buffer volume change and enable fast electronic/ionic transport. The flexibility of the electrode was guaranteed by the flexible carbon foam substrate without any conducting agent and binder.

Adoptive transfer of natural killer (NK) cells is becoming one of the most important parts of cancer immunotherapy. However, recent accomplishments have focused on the improvement of the targeting effects based on the engineering of chimeric antigen receptors (CARs) on cell surfaces. Despite the large quantity of therapeutic cells required for clinical applications, the technology for ex vivo expansion is not well developed. Herein, a three-dimensional (3D) engineered hyaluronic acid-based niche for cell expansion (3D-ENHANCE) is introduced. Compared with the conventional two-dimensional (2D) method, NK-92 cell lines and human EGFR-specific (CAR)–NK cells cultured in 3D-ENHANCE yield favorable mRNA expressions, elevated cytokine release, upregulated proliferative and tumor-lytic abilities, and result in enhanced antitumor efficacy. Furthermore, controllable degradation rates can be realized by tuning the formulation of 3D-ENHANCE so that it can be applied as an implantable cell reservoir at surgical sites. In vivo results with the incompletely resected MDA-MB-231 model confirm that the peri-operative implantation of 3D-ENHANCE prevents the relapse and metastases after surgery. Overall, 3D-ENHANCE presents an effective cytokine-free niche for ex vivo expansion and postsurgical treatment that enhances the low-therapeutic efficacy of human NK cells.

We report an efficient nanostructure of three-dimensional germanium/germanium dioxide (Ge/GeO2) shell-encapsulated niobium pentoxide (Nb2O5) nanoparticle assemblies for high-performance Li storage anode materials. The Ge/GeO2-encapsulated Nb2O5 nanoassemblies are prepared via a simple solvothermal synthesis method. The Ge/GeO2 layer binds the surfaces and interfaces of the interconnected Nb2O5 nanoparticle assemblies, presenting as dense and uniform microspheres. The tightly bound Ge/GeO2 layer interconnects the nanoassemblies to provide high capacity and a pathway for Li+ and electron transport. Via the Nb2O5 assemblies, fast Li+ transport kinetics are secured using a pseudocapacitive reaction mechanism during Li insertion and extraction, while Ge nanoparticles provide the high specific capacity. As a result, the Ge/GeO2-encapsulated Nb2O5 microspheres deliver a greatly enhanced reversible capacity of 800 mA h g−1 and excellent high-rate capability. The superior high-performance in Ge/GeO2-encapsulated Nb2O5 microspheres arises from a synergetic effect between the interconnected microstructure and the highly reversible GeO2 phase. The encapsulated interconnection material design concept allows control of the Ge-based electrode materials composition making it ideal for fabrication of high-performance electrodes in Li-ion batteries.

A palladium-catalyzed oxidative arylation of chromones was examined. A regioselective 2-arylation of chromone was carried out via a double C–H activation process. The procedure provided an expedient approach for the preparation of flavone derivatives.

A palladium-catalyzed oxidative homo-coupling of 1,3-dimethyluracil was examined. Two types of uracil dimer, C5–C5′ linked dimer and C5–C6′ linked dimer were obtained in variable yields depending on the conditions along with a low yield of C5–C5′ and C6–C5′ linked uracil trimer.

Palladium-catalyzed intramolecular arylation at the C-6 position of uracil moiety was examined. Morita–Baylis–Hillman adducts bearing an uracil moiety at the primary position served an efficient way to a benzo[c]pyrimido[1,6-a]azepine scaffold.

An efficient method of palladium-catalyzed direct 5-arylation of 1,3-dimethyluracil was developed with a various range of aryl bromides including electron-deficient aryl bromides. 5-Aryluracil derivatives were obtained in moderate to good yields regioselectively most likely via an electrophilic metalation–deprotonation process.

An efficient synthetic method of 3-methyleneindan-1-ol scaffold was developed from Baylis–Hillman adducts. The reaction involved palladium-catalyzed 5- exo-trig cyclization and iodide ion-assisted formal δ-carbon elimination/decarboxylation process.

An efficient and regioselective introduction method of 2-methylpyridines to the secondary position of Baylis–Hillman adducts has been developed. A base treatment of 2-methylpyridinium salt of Baylis–Hillman bromide generated N-allylenamine intermediate which underwent a facile 3-aza-Cope rearrangement under mild conditions to produce the product.

This randomized trial enrolled 442 infants in the Republic of Korea to assess the immunogenicity and safety of a combined diphtheria, tetanus, acellular pertussis, and inactivated poliovirus vaccine (DTaP-IPV; Tetraxim™) for primary vaccination at 2, 4 and 6 months of age compared with DTaP and IPV vaccines given separately. Immunogenicity was high in both groups; seroprotection and seroconversion rates of the combined vaccine (Group A) were non-inferior to the control vaccines (Group B). All subjects were seroprotected against poliovirus types 1, 2 and 3 (≥ 81/dil) and anti-diphtheria (≥ 0.01 IU/mL); 99.0% were seroprotected against tetanus (≥ 0.1 IU/mL). At least 93.6% had anti-diphtheria antibody titers ≥ 0.1 IU/mL. Anti-pertussis toxoid (PT) and anti-filamentous haemagglutinin (FHA) seroconversion (≥ 4-fold increase in antibody titer) rates were 96.6% and 94.4% for Group A, 92.2% and 78.4% for Group B. Most solicited reactions occurred within 4 days of vaccination, resolved within 3 days and were mild. Severe solicited reactions occurred after ≤ 0.5% of doses in Group A and ≤ 0.9% in Group B. No withdrawals occurred because of adverse events. The DTaP-IPV combined vaccine given at 2, 4, and 6 months of age was well tolerated; immunogenicity was similar to the control vaccines.

Poly-substituted naphthalenes were synthesized via a Pd-catalyzed cyclization of modified Baylis–Hillman adducts having an o-bromophenyl acetonitrile moiety at the secondary position, in reasonable yields. The reaction involved a sequential 6-endo Heck reaction and an aerobic oxidation process.

An expedient synthetic procedure of indolo[1,2-a]quinolines was developed using a sequential Cu-mediated N-arylation of indole, Mn(OAc)3-mediated oxidative free radical cyclization, and NaI/O2-assisted concomitant dealkoxycarbonylation/aerobic oxidation. The last step was replaced by a palladium-catalyzed decarboxylation/elimination protocol for the allyl ester derivatives.

Modified Baylis–Hillman adducts having 2-bromophenyl acetonitrile moiety at the primary position underwent a Pd-catalyzed cascade reaction to provide poly-substituted naphthalene derivatives in reasonable yields. The reaction involved a sequential 5-exo-carbopalladation, C(sp3)–H activation to cyclopropane, ring-opening and concomitant aromatization processes.

An efficient synthetic method was developed for poly-substituted naphthalenes via the multi-step, one-pot domino reaction of δ-ketonitriles involving a sequential Michael addition, intramolecular aldol, lactonization, decarboxylative Michael addition, and elimination processes.

We developed an efficient synthetic strategy of poly-substituted 1-arylisoquinolines via an indium-mediated Barbier type allylation from δ-ketonitriles. Initial attack of allylindium species occurred at the nitrile group selectively to form the enamine intermediate, which reacted with the ketone group intramolecularly to furnish the isoquinolines.

The reaction of Baylis–Hillman acetates and ethyl mercaptoacetate in the presence of DBU in DMF produced 2,3,4-trisubstituted tetrahydrothiophenes at room temperature as a diastereomeric mixture via the sequential SN2′ and Michael addition. Aromatization of tetrahydrothiophenes by DDQ oxidation produced 2,3,4-trisubstituted thiophenes in good yields.

An efficient palladium-catalyzed two-step protocol for the synthesis of Baylis–Hillman adducts of acrylamide was developed. The method involved the preparation of Baylis–Hillman adducts of acrylonitrile and a Pd-catalyzed hydration of nitrile with acetaldoxime.

Modified Baylis–Hillman adducts having 2-bromoaniline moiety at the primary position underwent Pd-mediated reductive Heck type cyclization to produce dihydroindole derivatives. The same starting materials can also be used for the synthesis of indole derivatives under slightly different conditions via the concomitant δ-carbon elimination and decarboxylation process.

An expedient protocol for the synthesis of β-aralkyl cycloalkanones was developed via the conjugate addition of allyl arylacetate to cycloalkenones and the following Pd-catalyzed decarboxylative protonation strategy.

An expedient method was developed for the synthesis of 1,4,5,6-tetrahydropyridines by radical cyclization protocol involving consecutive 1,5-hydrogen transfer and double bond isomerization process starting from Baylis–Hillman adducts.

An expedient protocol of aralkylation of Baylis–Hillman adducts has been developed. This method used Pd-catalyzed decarboxylative protonation strategy to the allyl ester precursor that was made from the Baylis–Hillman adduct and allyl phenylacetate.

Rational structural design of ships or offshore platforms against collisions requires prediction of the extent of damage to stiffened plates generated by lateral impact. In predicting the extent of collision damage, most researchers employ numerical analysis methods using commercial software packages. Like other structural problems, any nonlinear dynamic analysis methods should be substantiated with relevant test data prior to being employed for design. Unfortunately, full-scale collision tests on marine structures are very rare. Still, results from collision tests on marine structural elements can help to substantiate theoretical methods for collision analyses. Lateral collision test data for unstiffened plates are available, but it is difficult to find results from tests on stiffened plates in the open literature. In this paper, the results of lateral collision tests on 33 stiffened plates are reported. A simplified analytical method is developed for the prediction of the extent of damage to stiffened plates due to lateral collisions and this method is substantiated with the test results. Also proposed is a simple criterion with which the occurrence of crack damage can be judged.

Regioselective ortho-hydroxylation of aryl moiety of 2-arylpyridines was carried out under the influence of Pd(OAc)2/Oxone (potassium peroxymonosulfate) in PEG-3400/t-BuOH in moderate yields.

We synthesized 2-arylquinolines and tetrahydropyridines via palladium-mediated Heck type reactions starting from the Baylis–Hillman adducts. 2-Arylquinolines were prepared via the Heck type cyclization followed by concomitant aerobic oxidation.

We synthesized novel tetracyclic fused indole derivatives via the intramolecular Heck reaction of indole-containing Baylis–Hillman adducts in good to moderate yields.

N-Tosyl-3,3-disubstituted-4-vinylpyrrolidine derivatives 3a–c were synthesized via radical cyclization from the modified Baylis–Hillman adducts 2. The required starting materials 2a–c were prepared in moderate yields from the Baylis–Hillman adducts in three steps: (i) acetylation of the Baylis–Hillman adducts, (ii) SN2′ reaction with tosylamide to prepare 1, and (iii) alkylation with 1,4-dibromo-2-butene.

Novel pentacyclic benzoazepino[2,1-a]isoindole derivatives were synthesized by palladium-mediated consecutive cyclization from enamides of Baylis–Hillman adducts.

We synthesized poly-substituted pyrrole derivatives 4a–e, 7a–c and 10a–d from the reaction of phenacyl bromide and the aza-Baylis–Hillman adducts 1a–d or their rearranged derivatives 5a–e. The pyrroles were synthesized via the successive N-alkylation, Michael addition, elimination of p-toluenesulfinic acid and oxidative aromatization processes.

3,5,6-Trisubstituted α-pyrones were synthesized starting from the Baylis–Hillman adducts. The synthesis was carried out via the sequential introduction of ketone at the primary position of Baylis–Hillman adduct, lactonization, and the following oxidation with PCC.

Polysubstituted phenol derivatives were synthesized regioselectively starting from the Baylis–Hillman adducts via the formal [4+2] annulation protocol as the key step.

We developed an efficient synthetic method of diallylated δ-valerolactam and γ-butyrolactam derivatives via an indium-mediated successive double Barbier type allylations starting from the Baylis–Hillman adducts.

3,4-Disubstituted 2(1H)-quinolinones were synthesized starting from the Baylis–Hillman adducts via the following sequential processes: (i) hydrolysis of the Baylis–Hillman adduct to acid, (ii) EDC coupling with anilines, (iii) H2SO4-assisted intramolecular Friedel–Crafts cyclization, and the final (iv) DBU-mediated isomerization.