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Motivated by the Swampland Distance and the Emergent String Conjecture of Quantum Gravity, we analyse the infinite distance degenerations in the complex structure moduli space of elliptic K3 surfaces. All complex degenerations of K3 surfaces are known to be classified according to their associated Kulikov models of Type I (finite distance), Type II or Type III (infinite distance). For elliptic K3 surfaces, we characterise the underlying Weierstrass models in detail. Similarly to the known two classes of Type II Kulikov models for elliptic K3 surfaces we find that the Weierstrass models of the more elusive Type III Kulikov models can be brought into two canonical forms. We furthermore show that all infinite distance limits are related to degenerations of Weierstrass models with non-minimal singularities in codimension one or to models with degenerating generic fibers as in the Sen limit. We explicitly work out the general structure of blowups and base changes required to remove the non-minimal singularities. These results form the basis for a classification of the infinite distance limits of elliptic K3 surfaces as probed by F-theory in the companion paper [1]. The Type III limits, in particular, are (partial) decompactification limits as signalled by an emergent affine enhancement of the symmetry algebra. [ABSTRACT FROM AUTHOR]

We investigate infinite distance limits in the complex structure moduli space of F-theory compactified on K3 to eight dimensions. While this is among the simplest possible arenas to test ideas about the Swampland Distance Conjecture, it is nevertheless non-trivial enough to improve our understanding of the physics for these limiting geometries, including phenomena of emergence. It also provides a perspective on infinite distance limits from the viewpoint of open strings. The paper has two quite independent themes. In the main part we show that all degenerations of elliptic K3 surfaces at infinite distance as analysed in the companion paper [1] can be interpreted as (partial) decompactification or emergent string limits in F-theory, in agreement with the Emergent String Conjecture. We present a unified geometric picture of the possible towers of states that can become light and illustrate our general claims via the connection between Kulikov models of degenerating K3 surfaces and the dual heterotic string. As an application we classify the possible maximal non-abelian Lie algebras and their Kac-Moody and loop extensions that can arise in the infinite distance limits. In the second part we discuss the infinite distance behaviour of certain exact quartic gauge couplings. We encounter a tension with the hypothesis that effective couplings should be fully generated by integrating out massive states. We show that by appropriately renormalizing the string coupling, at least partial emergence can be achieved. [ABSTRACT FROM AUTHOR]

The T7 primase-helicase plays a pivotal role in the replication of T7 DNA. Using affinity isolation of peptide–nucleic acid crosslinks and mass spectrometry, we identify protein regions in the primase-helicase and T7 DNA polymerase that form contacts with the RNA primer and DNA template. The contacts between nucleic acids and the primase domain of the primasehelicase are centered in the RNA polymerase subdomain of the primase domain, in a cleft between the N-terminal subdomain and the topoisomerase-primase fold. We demonstrate that residues along a beta sheet in the N-terminal subdomain that contacts the RNA primer are essential for phage growth and primase activity in vitro. Surprisingly, we found mutations in the primase domain that had a dramatic effect on the helicase. Substitution of a residue conserved in other DnaG-like enzymes, R84A, abrogates both primase and helicase enzymatic activities of the T7 primase-helicase. Alterations in this residue also decrease binding of the primase-helicase to ssDNA. However, mass photometry measurements show that these mutations do not interfere with the ability of the protein to form the active hexamer. [ABSTRACT FROM AUTHOR]

Ammonium toxicity is a significant source of pollution from industrial civilization that is disrupting the balance of natural systems, adversely affecting soil and water quality, and causing several environmental problems that affect aquatic and human life, including the strong promotion of eutrophication and increased dissolved oxygen consumption. Thus, a cheap catalyst is required for power generation and detoxification. Herein, compost soil is employed as a novel electrocatalyst for ammonium degradation and high-power generation. Moreover, its effect on catalytic activity and material performances is systematically optimized and compared by treating it with various reducing agents, including potassium ferricyanide, ferrocyanide, and manganese dioxide. Ammonium fuel was supplied to the compost soil ammonium fuel cell (CS-AFC) at concentrations of 0.1, 0.2, and 0.3 g/mL. The overall results show that ferricyanide affords a maximum power density of 1785.20 mW/m2 at 0.2 g/mL fuel concentration. This study focuses on high-power generation for CS-AFC. CS-AFCs are sustainable for many hours without any catalyst deactivation; however, they need to be refueled at regular intervals (every 12 h). Moreover, CS-AFCs afford the best performance when ferricyanide is used as the electron acceptor at the cathode. This study proposes a cheap electrocatalyst and possible solutions to the more serious energy generation problems. This study will help in recycling ammonium-rich wastewaters as free fuel for running CS-AFC devices to yield high-power generation with reducing agents for ammonium fuel cell power applications. [ABSTRACT FROM AUTHOR]

We investigate holomorphic anomalies of partition functions underlying string compactifications on Calabi-Yau fourfolds with background fluxes. For elliptic fourfolds the partition functions have an alternative interpretation as elliptic genera of N = 1 supersymmetric string theories in four dimensions, or as generating functions for relative, genus zero Gromov-Witten invariants of fourfolds with fluxes. We derive the holomorphic anomaly equations by starting from the BCOV formalism of topological strings, and translating them into geometrical terms. The result can be recast into modular and elliptic anomaly equations. As a new feature, as compared to threefolds, we find an extra contribution which is given by a gravitational descendant invariant. This leads to linear terms in the anomaly equations, which support an algebra of derivatives mapping between partition functions of the various flux sectors. These geometric features are mirrored by certain properties of quasi-Jacobi forms. We also offer an interpretation of the physics from the viewpoint of the worldsheet theory, and comment on holomorphic anomalies at genus one. [ABSTRACT FROM AUTHOR]

As a refinement of the Swampland Distance Conjecture, we propose that a quantum gravitational theory in an infinite distance limit of its moduli space either decompactifies, or reduces to an asymptotically tensionless, weakly coupled string theory. We support our claim by classifying, as special cases, the behaviour of M-Theory and Type IIA string theory compactifications on Calabi-Yau three-folds at infinite distances in Kähler moduli space. The analysis comprises three parts: we first classify the possible infinite distance limits in the classical Kähler moduli space of a Calabi-Yau three-fold. Each such limit at finite volume is characterized by a universal fibration structure, for which the generic fiber shrinking in the limit is either an elliptic curve, a K3 surface, or an Abelian surface. In the second part we focus on M-Theory and investigate the nature of the towers of asymptotically massless states that arise from branes wrapped on the shrinking fibers. Depending on which of the three classes of fibrations are considered, we obtain decompactification to F-Theory, or a theory with a unique asymptotically tensionless, weakly coupled heterotic or Type II string, respectively. The latter probes a dual D-manifold which is in general non-geometric. In addition to the intrinsic string excitations, towers of states from M2-branes along non-contractible curves become light and correspond to further wrapping and winding modes of the tensionless heterotic or Type II string. In the third part of the analysis, we consider Type IIA string theory on Calabi-Yau three-folds and show that quantum effects obstruct taking finite volume infinite distance limits in the Kähler moduli space. The only possible infinite distance limit which is not a decompactification limit involves K3-fibrations with string scale fiber volume and gives rise to an emergent tensionless heterotic string. [ABSTRACT FROM AUTHOR]

We systematically analyse weak coupling limits for 2-form tensor fields in the presence of gravity. Such limits are significant for testing various versions of the Weak Gravity and Swampland Distance Conjectures, and more broadly, the phenomenon of emergence. The weak coupling limits for 2-forms correspond to certain infinite-distance limits in the moduli space of string compactifications, where asymptotically tensionless, solitonic strings arise. These strings are identified as weakly coupled fundamental strings in a dual frame, which makes the idea of emergence manifest. Concretely we first consider weakly coupled tensor fields in six-dimensional compactifications of F-theory, where the arising tensionless strings play the role of dual weakly coupled heterotic strings. As the main part of this work, we consider certain infinite distance limits of Type IIB strings on K3 surfaces, for which we show that the asymptotically tensionless strings describe dual fundamental Type IIB strings, again on K3 surfaces. By contrast the analogous weak coupling limits of M-theory compactifications are found to correspond to an F-theory limit where an extra dimension emerges rather than tensionless strings. We comment on extensions of our findings to four-dimensional compactifications. [ABSTRACT FROM AUTHOR]

We study quantum corrections in four-dimensional theories with N = 1 supersymmetry in the context of Quantum Gravity Conjectures. According to the Emergent String Conjecture, infinite distance limits in quantum gravity either lead to decompactification of the theory or result in a weakly coupled string theory. We verify this conjecture in the framework of N = 1 supersymmetric F-theory compactifications to four dimensions including perturbative α′ as well as non-perturbative corrections. After proving uniqueness of the emergent critical string at the classical level, we show that quantum corrections obstruct precisely those limits in which the scale of the emergent critical string would lie parametrically below the Kaluza-Klein scale. Limits in which the tension of the asymptotically tensionless string sits at the Kaluza-Klein scale, by contrast, are not obstructed. In the second part of the paper we study the effect of quantum corrections for the Weak Gravity Conjecture away from the strict weak coupling limit. We propose that gauge threshold corrections and mass renormalisation effects modify the super-extremality bound in four dimensions. For the infinite distance limits in F-theory the classical super-extremality bound is generically satisfied by a sublattice of states in the tower of excitations of an emergent heterotic string. By matching the F-theory α′-corrections to gauge threshold corrections of the dual heterotic theory we predict how the masses of this tower must be renormalised in order for the Weak Gravity Conjecture to hold at the quantum level. [ABSTRACT FROM AUTHOR]

We investigate the interplay between the enumerative geometry of Calabi-Yau fourfolds with fluxes and the modularity of elliptic genera in four-dimensional string theories. We argue that certain contributions to the elliptic genus are given by derivatives of modular or quasi-modular forms, which may encode BPS invariants of Calabi-Yau or non-Calabi-Yau threefolds that are embedded in the given fourfold. As a result, the elliptic genus is only a quasi-Jacobi form, rather than a modular or quasi-modular one in the usual sense. This manifests itself as a holomorphic anomaly of the spectral flow symmetry, and in an elliptic holomorphic anomaly equation that maps between different flux sectors. We support our general considerations by a detailed study of examples, including non-critical strings in four dimensions. For the critical heterotic string, we explain how anomaly cancellation is restored due to the properties of the derivative sector. Essentially, while the modular sector of the elliptic genus takes care of anomaly cancellation involving the universal B-field, the quasi-Jacobi one accounts for additional B-fields that can be present. Thus once again, diverse mathematical ingredients, namely here the algebraic geometry of fourfolds, relative Gromow-Witten theory pertaining to flux backgrounds, and the modular properties of (quasi-)Jacobi forms, conspire in an intriguing manner precisely as required by stringy consistency. [ABSTRACT FROM AUTHOR]

The vast majority of intracellular protein targets are refractory toward small-molecule therapeutic engagement, and additional therapeutic modalities are needed to overcome this deficiency. Here, the identification and characterization of a natural product, WDB002, reveals a therapeutic modality that dramatically expands the currently accepted limits of druggability. WDB002, in complex with the FK506-binding protein (FKBP12), potently and selectively binds the human centrosomal protein 250 (CEP250), resulting in disruption of CEP250 function in cells. The recognition mode is unprecedented in that the targeted domain of CEP250 is a coiled coil and is topologically featureless, embodying both a structural motif and surface topology previously considered on the extreme limits of "undruggability" for an intracellular target. Structural studies reveal extensive protein-WDB002 and protein-protein contacts, with the latter being distinct from those seen in FKBP12 ternary complexes formed by FK506 and rapamycin. Outwardfacing structural changes in a bound small molecule can thus reprogram FKBP12 to engage diverse, otherwise "undruggable" targets. The flat-targeting modality demonstrated here has the potential to expand the druggable target range of small-molecule therapeutics. As CEP250 was recently found to be an interaction partner with the Nsp13 protein of the SARS-CoV-2 virus that causes COVID-19 disease, it is possible that WDB002 or an analog may exert useful antiviral activity through its ability to form high-affinity ternary complexes containing CEP250 and FKBP12. [ABSTRACT FROM AUTHOR]

CCL2/CCR2 signaling is believed to play an important role in kidney diseases. Several studies have demonstrated that blocking of CCR2 has a therapeutic effect on kidney diseases. However, the effects of CCR2 knockout on obesity-induced kidney injury remain unclear. We investigated the therapeutic effects and the mechanism of CCL2/CCR2 signaling in obesity-induced kidney injury. We used C57BL/6-CCR2 wild type and C57BL/6-CCR2 knockout mice: Regular diet wild type (RD WT), RD CCR2 knockout (RD KO), High-fat diet WT (HFD WT), HFD CCR2 KO (HFD KO). Body weight of WT mice was significantly increased after HFD. However, the body weight of HFD KO mice was not decreased compared to HFD WT mice. Food intake and calorie showed no significant differences between HFD WT and HFD KO mice. Glucose, insulin, total cholesterol, and triglycerides levels increased in HFD WT mice were decreased in HFD KO mice. Insulin resistance, increased insulin secretion, and lipid accumulation showed in HFD WT mice were improved in HFD KO mice. Increased desmin expression, macrophage infiltration, and TNF-α in HFD mice were reduced in HFD KO mice. HFD-induced albuminuria, glomerular hypertrophy, glomerular basement membrane thickening, and podocyte effacement were restored by CCR2 depletion. HFD-induced elevated expressions of xBP1, Bip, and Nox4 at RNA and protein levels were significantly decreased in HFD KO. Therefore, blockade of CCL2/CCR2 signaling by CCR2 depletion might ameliorate obesity-induced albuminuria through blocking oxidative stress, ER stress, and lipid accumulation. [ABSTRACT FROM AUTHOR]

Abstract We prove a version of the Weak Gravity Conjecture for 6d F-theory or heterotic string compactifications with 8 supercharges. This sharpens our previous analysis by including massless scalar fields. The latter are known to modify the Weak Gravity Conjecture bound in two a priori independent ways: First, the extremality condition of a charged black hole is modified, and second, the test particles required to satisfy the Weak Gravity Conjecture are subject to additional Yukawa type interactions. We argue on general grounds that at weak coupling, the two types of effects are equivalent for a tower of asymptotically massless charged test particles predicted by the Swampland Distance Conjecture. We then specialize to F-theory compactified on elliptic Calabi–Yau three-folds and prove that the precise numerical bound on the charge-to-mass ratio is satisfied at weak coupling. This amounts to an intriguing coincidence of two a priori different notions of extremality, namely one based on the balance of gauge, gravitational and scalar forces for extremal (non-BPS) black holes, and the other encoded in the modular properties of certain Jacobi forms. In the presence of multiple abelian gauge group factors, the elliptic genus counting these states is a lattice quasi-Jacobi form of higher rank, and we exemplify this in a model with two abelian gauge group factors. [ABSTRACT FROM AUTHOR]

Low GWP refrigerants have been extensively paid attention to solve the environmental problems. Meanwhile, the integration of systems such as a solar assisted heat pump has been also developed consistently to compensate shortcomings of individual systems and enhance the efficiency of the system. In this study, the performance of the novel type solar assisted heat pump system using a low GWP refrigerant (R-1233zd(E)) with the flexible solar collector is investigated by experiments. R-1233zd(E) is a low GWP refrigerant with GWP lower than 7.0. The performance of solar assisted heat pump system using R-1233zd(E) is firstly compared with that using R-134a. From the study, it is found that the flexible solar collector shows the average efficiency of 40% irrespective of the weather conditions. In addition, high performance of the solar assisted heat pump using R-1233zd(E) is obtained by controlling the mass flow rate and heat source temperature. Finally, although the heat capacity of the solar assisted heat pump using R-1233zd(E) is lower than that with R-134a at same conditions, COP of the system using R-1233zd(E) shows a higher value due to low power consumption rate compared to that using R-134a. [ABSTRACT FROM AUTHOR]

This paper proposes a novel switching method with the neutral-point voltage control in a single-phase neutral-point-clamped three-level inverter (SP-NPCI) used in photovoltaic systems. A proposed novel switching method for the SP-NPCI improves the efficiency. The main concept is to fix the switching state of one leg. As a result, the switching loss decreases and the total efficiency is improved. In addition, it enables the maximum power-point-tracking operation to be performed by applying the proposed neutral-point voltage control algorithm. This control is implemented by modifying the reference signal. Simulation and experimental results provide verification of the performance of a novel switching method with the neutral-point voltage control. [ABSTRACT FROM AUTHOR]

We study the density of states (DOS) in a cylindrical quantum box formed by a cylindrical penetrable barrier and a planer penetrable double barrier perpendicular to the cylinder. The control of the cylindrical barrier thickness or height is found to cause the dimensional transitions from a three-dimensional (3D) DOS to a quasi-one-dimensional (Q1D) DOS and from a quasi-two-dimensional (Q2D) DOS to a quasi-zero-dimensional (QOD) DOS, if the strength of the planer double barrier is zero and infinity, respectively. In between the 3D and the Q1D (Q2D and QOD) limiting regimes, we found the presence of a Q2D (Q1D) like crossover regime. [ABSTRACT FROM AUTHOR]

We investigated the effect of organic polar solvent on the properties of [6,6]-phenyl-C 71 -butyric acid methyl ester (PCBM) films and poly(3-hexylthiophene) (P3HT):PCBM blend films employed as active layer in organic photovoltaic. The nanoscale morphology and the electrical characteristics of the P3HT:PCBM film can be controlled through organic polar solvent exposure, which exhibited with a short-circuit current density of 8.64 mA/cm 2 , an open circuit voltage of 0.63 V, and a power conversion efficiency of 3.29% under AM 1.5 illumination with a light intensity of 100 mW/cm 2 . By exposing the active layer films to organic polar solvent a favorable phase separation in the P3HT:PCBM films is obtained. The improved power conversion efficiency can be to the high conductivity and high surface area of the P3HT:PCBM layer treated with organic polar solvent. [ABSTRACT FROM AUTHOR]

In immunocompetent individuals, non-typhoidal Salmonella serovars (NTS) are associated with gastroenteritis, however, there is currently an epidemic of NTS bloodstream infections in sub-Saharan Africa. Plasmodium falciparum malaria is an important risk factor for invasive NTS bloodstream in African children. Here we investigated whether a live, attenuated Salmonella vaccine could be protective in mice, in the setting of concurrent malaria. Surprisingly, mice acutely infected with the nonlethal malaria parasite Plasmodium yoelii 17XNL exhibited a profound loss of protective immunity to NTS, but vaccine-mediated protection was restored after resolution of malaria. Absence of protective immunity during acute malaria correlated with maintenance of antibodies to NTS, but a marked reduction in effector capability of Salmonella-specific CD4 and CD8 T cells. Further, increased expression of the inhibitory molecule PD1 was identified on memory CD4 T cells induced by vaccination. Blockade of IL-10 restored protection against S. Typhimurium, without restoring CD4 T cell effector function. Simultaneous blockade of CTLA-4, LAG3, and PDL1 restored IFN-γ production by vaccine-induced memory CD4 T cells but was not sufficient to restore protection. Together, these data demonstrate that malaria parasite infection induces a temporary loss of an established adaptive immune response via multiple mechanisms, and suggest that in the setting of acute malaria, protection against NTS mediated by live vaccines may be interrupted. [ABSTRACT FROM AUTHOR]

Summary The B cell response to Salmonella typhimurium (STm) occurs massively at extrafollicular sites, without notable germinal centers (GCs). Little is known in terms of its specificity. To expand the knowledge of antigen targets, we screened plasmablast (PB)-derived monoclonal antibodies (mAbs) for Salmonella specificity, using ELISA, flow cytometry, and antigen microarray. Only a small fraction (0.5%–2%) of the response appeared to be Salmonella -specific. Yet, infection of mice with limited B cell receptor (BCR) repertoires impaired the response, suggesting that BCR specificity was important. We showed, using laser microdissection, that somatic hypermutation (SHM) occurred efficiently at extrafollicular sites leading to affinity maturation that in turn led to detectable STm Ag-binding. These results suggest a revised vision of how clonal selection and affinity maturation operate in response to Salmonella. Clonal selection initially is promiscuous, activating cells with virtually undetectable affinity, yet SHM and selection occur during the extrafollicular response yielding higher affinity, detectable antibodies. [ABSTRACT FROM AUTHOR]

A combination of graphene nanoribbons (GNRs) and carbon nanotubes (CNTs) was deployed as a potential candidate to replace the commonly used hole transport material poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) in a high performance organic photovoltaic. A power conversion efficiency (PCE) of 7.6% has been obtained using inkjet printing to fabricate the photovoltaic along with the presence of C60-bis as an electron transporting material. [ABSTRACT FROM AUTHOR]

Herein, we report about an efficient and stable organic photovoltaic that uses a poly(3,4-ethylenedioxythiophene):poly(styrene-sulfonate) (PEDOT:PSS) and molybdenum oxide (MoO X ) mixture for the anode interfacial layer, and that can reach 4.43% power conversion efficiency (PCE) under AM1.5 conditions. Utilizing PEDOT:PSS:MoO X (1:1), the shelf lifetime of poly(3-hexylthiophene) (P3HT), and indene-C 60 bisadduct (ICBA)-based solar cells without encapsulation, can be realized with only a 25% deterioration after 672 h of storage in air. Furthermore, we compare the photovoltaic performance of the P3HT:ICBA-based organic photovoltaic with PEDOT:PSS, and PEDOT:PSS:MoO X , in which PEDOT:PSS:MoO X has outperformed the others. In addition, the water vapor transmission rate of PEDOT:PSS:MoO X is 0.17 gm/(m 2 day), which is much less than that of PEDOT:PSS. [ABSTRACT FROM AUTHOR]

A high-performance semitransparent tandem solar cell that uses solution-processed graphene mesh and laminated Ag NW as a transparent anode and cathode, respectively, is demonstrated. The laminated top electrode can be deposited without causing any damage to the underneath organic solar cells. Power conversion efficiencies of 8.02% and 6.47% are obtained when the light is projected from the solution-processed graphene mesh and laminated AgNW, respectively. The performance of the tandem cell is found to be comparable to a tandem solar cell fabricated using commercially available indium tin oxide. These findings offer a high-performance device and open a new pathway in searching for a potential replacement to the frequently used transparent conducting electrodes. [ABSTRACT FROM AUTHOR]

Highlights: [•] Profiles of makgeolli samples are determined using sensory descriptive, chemical, and volatile compounds analyses. [•] The chemical compositions of makgeolli samples are found to be significantly different. [•] In all, 45 major volatile compounds are identified from makgeolli. [•] The chemical and volatile compounds show a significant relevance to the related sensory attributes of makgeolli. [Copyright &y& Elsevier]

A power conversion efficiency of up to 8.91% is obtained for a solution-processed polymer tandem solar cells based on a large-bandgap polymer, poly(4,4-dioctyldithieno(3,2-b:2′,3′-d)silole)-2,6-diyl- alt-(2,1,3-benzothiadiazole)-4,7-diyl) with a polymeric interconnecting layer to electrically connect the front and rear subcells, demonstrating that proper device and interface engineering are can improve the performance of polymer tandem solar cells. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we report on organic photovoltaics based on inverted structure with the photoactive layer sandwiched between lithium zinc oxide electron transport layer and PEDOT:PSS doped with V2O5 hole transport layer. The efficiency of the PEDOT:PSS device increases from 4.04 to 4.20% as we doped with V2O5. This inverted organic photovoltaic can retain efficiency with only 1.9% degradation after 3 weeks storage in ambient conditions. The degradation rate for PEDOT:PSS device is significantly higher (11.6%) compared to PEDOT:PSS doped with V2O5. The good stability in our device can be attributed to the air stable PEDOT:PSS doped with V2O5 HTL as the interfacial layers. It is found that the degradation rate decreases with increasing V2O5 concentration in PEDOT:PSS. [Copyright &y& Elsevier]

Abstract: In this paper, we propose a simple and effective feature-aware filtering for point-set surface denoising, which can achieve a second-order surface approximation of the underlying surface. Our method consists of two stages: robust normal estimation considering sharp features and feature-preserving denoising using a local curvature based projection. The normal clustering based on neighborhood grouping allows the filter to preserve and respect several features during the denoising process. We demonstrate the strength of our method in terms of denoising, feature preservation and computational efficiency. [Copyright &y& Elsevier]

Abstract: Protective immunity against Salmonella infection is known to require CD4 Th1 cells and B cells, but the role of MHC class-I-restricted CD8 T cells is less clear. Previous studies have suggested that CD8 T cells participate in secondary, but not primary, bacterial clearance. However, these studies have used experimental models that are difficult to interpret and do not clearly isolate the role of MHC class-I-restricted CD8 T cells from other cell populations. Here, we examined the role of class-I-restricted T cells in protection against Salmonella infection using mice lacking all classical MHC class-Ia molecules, perforin, or granzyme B. Immunized KbDb-, perforin-, granzyme B-, or perforin/granzyme B-deficient mice were able to resolve secondary infection with virulent Salmonella, demonstrating that class-I-restricted CTLs are not required for acquired immunity. However, during primary infection with attenuated bacteria, bacterial clearance was delayed in each of these mouse strains when compared to wild-type mice. Taken together, these data demonstrate that CD8 T cells are not required for acquired immunity to Salmonella, but can play a protective role in resolving primary infection with attenuated bacteria. [Copyright &y& Elsevier]

Purpose: This study aims to report the long-term results of lateral release and medial plication in patients with recurrent patellar dislocation. Methods: In this study, 31 patients who underwent surgery for recurrent patellar dislocation were retrospectively reviewed between 1994 and 2004. Among the 31 patients were 12 male and 19 female patients. The average age was 23.9 ± 4.8 years, and the mean follow-up period was 11.6 ± 2.4 years. Results: Three patients had postoperative dislocations. The mean Kujala score significantly improved from 57.5 ± 13.2 points preoperatively to 89.2 ± 8.7 points at the final follow-up ( P < 0.0001). The median Tegner activity score significantly improved from 3 (range, 1-5) at preoperative examination to 7 (range, 3-9) at the final follow-up ( P < 0.0001). Ten patients were rated as excellent, 18 as good, 2 as fair, and 1 as poor. The congruence angle improved from 16.5° ± 3.0° to −2.8° ± 2.7°, and the lateral patellofemoral angle improved from −4.2° ± 1.9° to 8.2° ± 2.5°. There was no case of osteoarthritis at the final follow-up. Conclusions: Percutaneous lateral release and medial plication showed satisfactory results with limited morbidity in the long-term follow-up. This traditional method remains a simple and effective surgical procedure for recurrent patellar dislocation. Level of evidence: Therapeutic, Level IV. [ABSTRACT FROM AUTHOR]

The replication system of phage T7 provides a model for DNA replication. Biochemical, structural, and single-molecule analyses together provide insight into replisome mechanics. A complex of polymerase, a processivity factor, and helicase mediates leading strand synthesis. Establishment of the complex requires an interaction of the C-terminal tail of the helicase with the polymerase. During synthesis the complex is stabilized by other interactions to provide for a processivity of 5 kilobase (kb). The C-terminal tail also interacts with a distinct region of the polymerase to captures dissociating polymerase to increase the processivity to >17kb. The lagging strand is synthesized discontinuously within a loop that forms and resolves during each cycle of Okazaki fragment synthesis. The synthesis of a primer as well as the termination of a fragment signal loop resolution. [ABSTRACT FROM AUTHOR]

Abstract: In this study, the volatile compounds in nine fermented soybean pastes were extracted and analysed by simultaneous steam distillation and extraction (SDE) and gas chromatography–mass spectrometry (GC–MS), respectively. A total of 91 volatile components were identified. The differences in volatiles were observed by applying principal component analyses (PCA) to GC–MS data sets. Most of the samples did not show apparent groupings; however, a three sample clustering (CJW, SIN and HAE) was observed for pastes made by Aspergillus oryzae inoculation. From the PCA of the sensory data, samples are primarily separated along the first PC (explained 68% of the total variance), between samples like SUJA, CHJA and SOHI with high intensities of ‘briny’, ‘soy sauce’, ‘musty’ and ‘astringent’ and the samples (CJW and SIN) with intense levels in ‘sweet-grain’, ‘sweet’ and ‘MSG’ attributes. The individual concentrations of volatile compounds such as isoamyl acetate, furfuryl alcohol, maltol, pyrazines, 1-octen-3-ol and 2-methoxy-4-vinyl phenol corresponded well to the intensities of related sensory attributes by the correlation analysis. [Copyright &y& Elsevier]

We evaluate analytically and numerically the density of states (DOS) and the heat capacity in a spherical quantum dot formed by a spherical thin barrier. The control of the spherical barrier thickness or the potential barrier height is found to cause the dimensional transition from the three-dimensional (3D) behavior to the quasi-zero dimensional (Q0D) behavior in the DOS and the heat capacity. When the barrier is thick enough, the DOS shows the Q0D-like behavior but when the barrier is thin enough to allow electrons to tunnel through it, the temperature dependence of the heat capacity exhibits quite a distinct behavior depending on the electron density. Explicit numerical plots are given in the low density regime. [ABSTRACT FROM AUTHOR]

Abstract: In this study, two red wines were developed, with and without sugar addition, from a mixture of two different grape varieties, Gerbong (Vitis labrusca L.) 60% and Campbell Early (V. labrusca B.) 40%. Their chemical and sensory profiles were determined and compared with a French Beaujolais Nouveau wine of Chateau Talance using descriptive, physicochemical and volatile analyses. Colour, six aroma, and five taste attributes were evaluated by an expert panel of nine judges. Sample wines were analyzed for titratable acidity, ethanol, pH, Hunter colorimeter value, phenolic compounds, and organic acids. From the volatile analysis of sample wines, 10 acids, 12 alcohols, 10 esters, 7 volatile phenols, 5 furans, and 3 miscellaneous compounds were identified. From the principal component analysis of the descriptive data, wines were primarily separated along the first PC, which explained 93% of the total variance between the Korean wines with high intensities of “ripe-fruit aroma”, “caramel aroma”, and “sour” attributes and the French wine that was high in “woody aroma”, “astringent”, “mineral aroma”, and “colour” attributes. [Copyright &y& Elsevier]

Abstract: This paper presents the development, laboratory evaluation, and field tests of a personal respirable particulate sampler (PRPS). The PRPS is designed as a personal sampling system to collect particulate matter (PM0.5, PM1.0, PM2.5, PM4.5, and PM10) and gaseous pollutants, including O3, SO2, and NO2. It operates at a flow rate of 5.0LPM and consists of five selectable impaction stages (with cutpoints of 10, 4.5, 2.5, 1.0, and 0.5μm), a backup filter, and two diffusion passive samplers. In each impaction stage, particles are collected onto a polyurethane foam (PUF) substrate. This substrate, using no adhesive, was shown to have minimum particle bounce and re-entrainment. A backup 37mm Teflon membrane filter is used downstream to collect particles smaller than the cutoff diameter of the final impaction stage. The impaction stage cutpoints were characterized in the laboratory using artificially generated polydisperse aerosols. Particle losses for each stage were found to be acceptably low. The performance of the PRPS was also compared with that of a collocated micro-orifice cascade impactor (MOI) and real-time particle sizing instruments (SMPS/APS) in laboratory experiments using artificially generated particles. The size distributions measured by the PRPS were found to be much closer to those measured by the real-time particle sizing instruments than to those measured by the MOI. A field PM intercomparison study was also conducted using the PRPS and three reference samplers, the Harvard Impactor (HI), the USEPA PM2.5 Well Impactor Ninety Six (WINS), and the Harvard Personal Environmental Monitor (Harvard PEM) sampler. The PM10, PM2.5, and sulfate concentrations measured by PRPS were in a very good agreement with those obtained from the reference samplers. [Copyright &y& Elsevier]

We study the ferromagnetism in III-V diluted magnetic semiconductor (DMS) quantum-wells theoretically and numerically taking into account the occupation of multiple subbands by holes in quantum wells. Starting from the mean-field theory of carrier-induced ferromagnetism in III-V DMS along with the exchange-correlation interaction of holes within the local spin density approximation, we found that the ferromagnetic transition temperature Tc of DMS quantum-wells exhibits step-function-like dependence on the hole density, reflecting the quasi-two-dimensional nature of systems. Moreover, the temperature dependence of the spin polarization shows quite distinct characteristics depending on the hole density. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents the results from the systematic performance evaluation tests of commonly used impaction substrates including uncoated metal plate, teflon membrane filter, greased metal plate, oiled sintered porous metal, and polyurethane foam (PUF), at various loading conditions. A single stage impactor and artificially generated aerosol composed of polydisperse glass beads were used to test the substrates. Significant particle bounce was observed for both the uncoated metal plate and Teflon filter substrate for particles larger than the impactor cutpoints () at very low loading conditions. Particle bounce decreased with increasing particle loading until it reaches a plateau at a loaded mass of approximately 3mg. A shift of collection efficiency curve was also observed, including a decrease of for both the uncoated metal and the teflon filter. Despite the fact that the collection efficiency for particles larger than remained high (95%) and constant up to about 30mg of collected mass on the greased and the oiled sintered metal, an indication for minimum particle bounce and re-entrainment, a decrease of the was also observed. However, while the changes in collection efficiency curve with increased loading and the consequent decreases of were significant for the greased and oiled sintered metal substrate, for the PUF substrate, neither substantial particle-bounce nor significant changes in collection efficiency were observed. For PUF, the collection efficiency remained high (98%) for particles larger than the for upto 30mg of collected mass. The changes of the on PUF are considerably less than those for the flat and rigid substrates. These results comprise a comprehensive confirmation that the nature of the impaction substrate has a significant effect on the particle bounce and particle separation performance of conventional inertial impactors. [Copyright &y& Elsevier]

Abstract: Aroma compounds in the extracts of basil leaves (Ocimum basilicum L.) and thyme leaves (Thymus vulgaris L.) were identified by gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). The major aroma constituents of basil were 3,7-dimethyl-1,6-octadien-3-ol (linalool; 3.94 mg/g), 1-methoxy-4-(2-propenyl) benzene (estragole; 2.03 mg/g), methyl cinnamate (1.28 mg/g), 4-allyl-2-methoxyphenol (eugenol; 0.896 mg/g), and 1,8-cineole (0.288 mg/g). The major aroma constituents of thyme were 2-isopropyl-5-methylphenol (thymol; 8.55 mg/g), 4-isopropyl-2-methylphenol (carvacrol; 0.681 mg/g), linalool (0.471 mg/g), α-terpineol (0.291 mg/g), and 1,8-cineole (0.245 mg/g). Twelve aroma constituents of basil and thyme were examined for their antioxidant activities using the aldehyde/carboxylic acid assay. Eugenol, thymol, carvacrol, and 4-allylphenol showed stronger antioxidant activities than did the other components tested in the assay. They all inhibited the oxidation of hexanal by almost 100% for a period of 30 days at a concentration of 5 μg/ml. Their antioxidant activities were comparable to those of the known antioxidants, α-tocopherol and butylated hydroxy toluene (BHT). [Copyright &y& Elsevier]

Abstract: The inhibitory effect of aroma extracts isolated from dried soybeans, mung beans, kidney beans, and azuki beans on malonaldehyde (MA) formation from horse blood plasma oxidized with Fenton’s reagent was determined by gas chromatography (GC) coupled with nitrogen–phosphorus detector (NPD). Aroma chemicals such as maltol, eugenol, benzyl alcohol, 1-octen-3-ol, butyrolactone, and 1-methyl-2-pyrrolidone, found in the aroma extracts of beans, were also examined for their inhibitory effect on the same system. Among the four aroma extracts tested, the aroma extract of soybeans exhibited the strongest antioxidant activity. Extracts of soybeans, mung beans, azuki beans, and kidney beans inhibited MA formation by 58%, 47%, 40%, and 23%, respectively, at the level of 400μg/mL, whereas, α-tocopherol and BHT inhibited MA formation by 52% and 70%, respectively, at the same level. Among the tested aroma chemicals, the antioxidant activity decreased in the following order: eugenol>maltol>1-octen-3-ol>benzyl alcohol>butyrolactone>1-methyl-2-pyrrolidone. [Copyright &y& Elsevier]

This paper presents the development, laboratory characterization, and field evaluation of a compact multistage cascade impactor (CCI). The CCI operates at a flow rate of 30 LPM and consists of eight impaction stages equipped with rectangular slit-shaped acceleration nozzles. A 47 mm backup Teflon membrane filter is used downstream of the eighth stage to collect particles smaller than 0.16 μm. In each stage, particles are retained by impaction onto the inert polyurethane foam (PUF) substrate. The major feature of this novel sampler is its ability to both fractionate by size and collect relatively large amounts of particles (mg quantities) onto an inert polyurethane foam impaction substrates. Even though the impaction substrates are not coated with adhesives such as grease or mineral oil, particle bounce and re-entrainment losses were found to be insignificant. Impaction characteristics (cutpoint and sharpness of collection efficiency curve) of the PUF substrates are maintained for mass loadings of at least 25 mg, which is much higher than for other commonly used rigid, flat impaction substrates. The system was calibrated in laboratory experiments using polydisperse aerosols. The 50% cutpoints of the eight stages were 9.9, 5.3, 3.3, 2.5, 1.7, 1.0, 0.47 and 0.16 μm (aerodynamic diameter), with pressure drops of 0.02, 0.02, 0.04, 0.06, 0.08, 0.27, 1.57 and 5.73 kPa. These pressure drops are considerably lower than those obtained using flat rigid impaction substrates with comparable cutpoints. Particle losses for each stage were less than 10% for particles smaller than 7 μm and less than 20% for particles larger than 7 μm. The CCI was also compared with the collocated micro-orifice impactor (MOI) in laboratory-controlled experiments using artificially generated polydisperse aerosol. These laboratory tests showed that the mass concentrations measured by the MOI are considerably lower than those measured by the CCI (the average ratio of total mass concentration of MOI to CCI was 0.86), with the size distribution measured by the CCI closer to that measured using the real time particle sizing instruments (SMPS, APS). A field comparison of CCI, the Harvard impactor (HI) and the federal reference method (FRM) for fine particles showed a good agreement between the CCI and the reference samplers for particles smaller than 2.5 μm. [Copyright &y& Elsevier]

A high loading sampler for the chemical characterization of fine particles (PM 2.5 ) was developed and validated through laboratory and field experiments. This speciation sampler consists of two identical serially connected impaction stages to remove particles larger than 2.5 μm, following by a chamber to allow use of one or two all-glass honeycomb diffusion denuders, and a holder for a 47 mm filter. Two configurations of the sampler allow sampling at flows of 10 lpm and 16.7 lpm. System performance was evaluated in laboratory experiments using artificially generated polydisperse aerosols. This novel sampler provides a much larger mass loading capacity than previous impactors that use flat, rigid substrate surfaces. The polyurethane foam (PUF) substrate maintains adequate performance characteristics (retention of size cut-off, sharpness of cut-off curve, and minimal particle bounce and re-entrainments) at loadings of at least 35 mg. This is equivalent to 728 μg/m 3 for a 48 h sampling period (or 500 h of sampling at 70 μg/m 3 ). System performance was also evaluated in a series of field intercomparison experiments for both flow configurations (10 and 16.7 lpm). Measurements of PM 2.5 mass and sulfate concentrations showed excellent agreement between the US EPA Federal Reference Method (FRM) Sampler and the speciation sampler. [ABSTRACT FROM AUTHOR]

Nitrogen-incorporated lithium silicophosphate (LiSiPON) thin-film electrolytes, which contain two glass-forming elements, are fabricated by sputtering from a (1−x)Li3PO4·xLi2SiO3 target in a nitrogen reactive plasma. The results of impedance measurements show that the activation energy for conduction decreases as the Si content increases, which leads to an increase in the ionic conductivity of the films. It is suggested that these improvements in the electrical properties of the films are due to the combined effect of the mixed former and nitrogen incorporation. It appears that the decomposition potential of the electrolyte film in contact with Pt is about 5.5 V. [Copyright &y& Elsevier]

Thin film Si/Ag and (Si–Zr)/Ag multilayer electrodes are fabricated on a Cu substrate by alternate sputtering from Si (–Zr) and Ag at room temperature, and their electrochemical properties are investigated. The insertion of the Ag layer into the Si layer improves the cycling performance. The cyclability can be further improved by doping Zr into the Si layer of the Si/Ag multilayer thin films. The effects of the electrode configuration and the contact stability between the current-collecting layer and the electrode on the cycling performance are discussed. [Copyright &y& Elsevier]

Zr–Si thin films were deposited on copper substrates by co-sputtering method of two pure targets. The structure and surface morphology of the films have been characterized by X-ray diffraction (XRD) and atomic force microscopy (AFM). The composition was measured by Rutherford backscattering spectroscopy (RBS) and energy-dispersive X-ray spectroscopy (EDS). The electrochemical results showed that alloying with Zr improves the cycling performance, while as a result the reversible capacity decreases. It appears that the electrochemical cycling performance can be further improved by controlling the film deposition conditions such as substrate temperature and bias sputtering. [Copyright &y& Elsevier]

Sn–Zr and Ag-doped Sn–Zr thin films were prepared by an electron-beam evaporation method using pure separate metal sources. Electrochemical cycling performance was obtained as a function of film composition. The cycling stability of Sn–Zr film electrodes increased with Zr content. An Ag-doped Sn–Zr thin film such as Sn57Zr33Ag10 showed excellent cycling stability and capacity retention. The composition dependence on electrochemical behavior is related to the microstructural changes in the films. [Copyright &y& Elsevier]

A thin film battery has been fabricated by depositing a LiCoO2 positive electrode, a Li1.9Si0.28P1.0O1.1N1.0 electrolyte, and a Si0.7V0.3 negative electrode, sequentially. The electrochemical characteristics of the Si0.7V0.3 electrode and the electrical conductivity of the Li1.9Si0.28P1.0O1.1N1.0 electrolyte are investigated. The thin film battery mainly operates in the voltage range between 3 and 3.5 V. It exhibits excellent cycling stability when cycled between 2.0 and 3.9 V, while the battery performance is abruptly deteriorated when the charge cutoff voltage is extended to 4.2 V. [Copyright &y& Elsevier]

Thin film, Sn, Cu–Sn and Sn–Zr–(O) anodes for microbatteries are deposited on a copper substrate by radio frequency (rf)-magnetron sputtering at room temperature. Charge–discharge characteristics are compared. It appears that the alloying of Sn with Cu or Zr improves the cycling performance. The best cycling efficiency is obtained when Sn is alloyed with Zr. The effects of alloying elements on the electrochemical properties on the thin film are discussed. [Copyright &y& Elsevier]

Development of high‐precision RGB patterning process is needed to implement high‐resolution micro display (OLEDoS) for next‐generation VR/AR products. In general, specially designed and manufactured masks are required to realize above 3000‐ppi high‐resolution display in structured OLED material deposition. In this study, we developed direct laser patterning IR‐fs optical system operating in MHz and GHz burst modes and evaluated its capability for precise micro‐drilling of aluminoborosilicate glass materials. The fine hole‐shaped pattern is produced at a minimum of 5 μm pitch level for about 0.6 in. area without sacrificing the glass strength. It is expected to contribute to the high precise manufacture of ultra fine mask (UFM) using thin glass platform corresponding to micro displays in the future. [ABSTRACT FROM AUTHOR]

Examines the replacement of the Bizelesin ureadiyl linkage by a guanidinium moiety. Retarded translocation from monoalkylation to cross-linkage sites on DNA; Required interplay of Bizelesin and the target sequence for cross-linking; Proposed structural basis of the hydrogen bonding of the guanidino linkage.

Proposes a mechanism for the covalent attachment of cytotoxic furan derivative psorospermin to guanine and determines the sequence selectivity for the reaction, using gel electrophoresis and high-field nuclear magnetic resonance (NMR). DNA strand breaks produced by psorospermin; Reactivity and sequence recognition; Structural interaction made with DNA.

The volatile compounds and sensory profiles of 18 different types of distilled soju, chosen with regard to various raw materials and distillation methods (atmospheric vs. vacuum), were explored using headspace solid-phase microextraction (HS-SPME) with gas chromatography-mass spectrometry (GC-MS) and descriptive analysis. General chemical properties such as pH, total acidity (TA), total soluble solids (°Brix), and lactic acid concentration were also determined. A total of 56 volatile compounds, comprising 31 esters, 11 alcohols, 1 acid, 4 aldehydes, 3 ketones, and 6 miscellaneous compounds, were identified. From the principal component analysis (PCA) of the volatile data, samples made using atmospheric distillation such as MSO and PJU showed a clear difference from decompressed distillation samples. Based on the PCA of the sensory data, there was also a clear distinction between samples by their distillation method. To explore relationships among chemical, volatile, and sensory data sets, multiple factor analysis (MFA) was applied. Yeasty and earthy flavors showed a close relationship with 1-nonanol, octatonic acid, and longer-chain esters such as ethyl phenylacetate and ethyl tetradecanoate, and with chemical parameters such as TA, °Brix, and lactic acid. [ABSTRACT FROM AUTHOR]