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The Freudenthal–Tits magic square m (A 1 , A 2) for A = R , C , H , O of semi-simple Lie algebras can be extended by including the sextonions S . A series of non-reductive Lie algebras naturally appear in the new row associated with the sextonions, which we will call the intermediate exceptional series, with the largest one as the intermediate Lie algebra E 7 + 1 / 2 constructed by Landsberg–Manivel. We study various aspects of the intermediate vertex operator (super)algebras associated with the intermediate exceptional series, including rationality, coset constructions, irreducible modules, (super)characters and modular linear differential equations. For all g I belonging to the intermediate exceptional series, the intermediate VOA L 1 (g I) has characters of irreducible modules coinciding with those of the simple rational C 2 -cofinite W-algebra W - h ∨ / 6 (g , f θ) studied by Kawasetsu, with g belonging to the Cvitanović–Deligne exceptional series. We propose some new intermediate VOA L k (g I) with integer level k and investigate their properties. For example, for the intermediate Lie algebra D 6 + 1 / 2 between D 6 and E 7 in the subexceptional series and also in Vogel’s projective plane, we find that the intermediate VOA L 2 (D 6 + 1 / 2) has a simple current extension to a SVOA with four irreducible Neveu–Schwarz modules, and the supercharacters can be realized by a fermionic Hecke operator on the N = 1 Virasoro minimal model L (c 16 , 2 , 0) . We also provide some (super) coset constructions such as L 2 (E 7) / L 2 (D 6 + 1 / 2) and L 1 (D 6 + 1 / 2) ⊗ 2 / L 2 (D 6 + 1 / 2) . In the end, we find that the theta blocks associated with the intermediate exceptional series produce some new holomorphic Jacobi forms of critical weight and lattice index. [ABSTRACT FROM AUTHOR]

ELO-like elongase is a condensing enzyme elongating long chain fatty acids in eukaryotes. Eranthis hyemalis ELO-like elongase (EhELO1) is the first higher plant ELO-type elongase that is highly active in elongating a wide range of polyunsaturated fatty acids (PUFAs) and some monounsaturated fatty acids (MUFAs). This study attempted using domain swapping and site-directed mutagenesis of EhELO1 and EhELO2, a close homologue of EhELO1 but with no apparent elongase activity, to elucidate the structural determinants critical for catalytic activity and substrate specificity. Domain swapping analysis of the two showed that subdomain B in the C-terminal half of EhELO1 is essential for MUFA elongation while subdomain C in the C-terminal half of EhELO1 is essential for both PUFA and MUFA elongations, implying these regions are critical in defining the architecture of the substrate tunnel for substrate specificity. Site-directed mutagenesis showed that the glycine at position 220 in the subdomain C plays a key role in differentiating the function of the two elongases. In addition, valine at 161 and cysteine at 165 in subdomain A also play critical roles in defining the architecture of the deep substrate tunnel, thereby contributing significantly to the acceptance of, and interaction with primer substrates.Key Message: Structural and functional analysis of the first higher plant ELO-type elongase. Structural factors critical for catalytic activity and substrate specificity determined. [ABSTRACT FROM AUTHOR]

We study the twisted elliptic genera of 2d (0, 4) SCFTs associated with the BPS strings in the twisted circle compactification of 6d rank-one (1, 0) SCFTs. Such objects can arise when the 6d gauge algebra allows outer automorphism, thus are classified by twisted affine Lie algebras. We study several fascinating aspects of the twisted elliptic genera including 2d localization, twisted elliptic blowup equations, Higgsing and spectral flow symmetry. We derive a recursion formula with respect to the number of strings to exactly compute the twisted elliptic genera. We also investigate the modular bootstrap of twisted one-string elliptic genera and find the modularity of congruence subgroups Γ1(N) naturally appears with possible N = 2, 3, 4. Geometrically, our study solves the refined BPS partition functions of the underlying genus-one fibered Calabi-Yau threefolds with N-section. [ABSTRACT FROM AUTHOR]

E 7 + 1 / 2 is an intermediate Lie algebra filling a hole between E 7 and E 8 in the Deligne–Cvitanović exceptional series. It was found independently by Mathur, Muhki, Sen in the classification of 2d RCFTs via modular linear differential equations (MLDE) and by Deligne, Cohen, de Man in representation theory. In this paper we propose some new vertex operator algebras (VOA) associated with E 7 + 1 / 2 and give some useful information at small levels. We conjecture that the affine VOA (E 7 + 1 / 2) k is rational if and only if the level k is at most 5, and provide some evidence from the viewpoint of MLDE. We propose a conjectural Weyl dimension formula for infinitely many irreducible representations of E 7 + 1 / 2 , which generates almost all irreducible representations of E 7 + 1 / 2 with level k ≤ 4 . More concretely, we propose the affine VOA E 7 + 1 / 2 at level 2 and the rank-two instanton VOA associated with E 7 + 1 / 2 . We compute the VOA characters and provide some coset constructions. These generalize the previous works of Kawasetsu for affine VOA E 7 + 1 / 2 at level 1 and of Arakawa–Kawasetsu at level - 5 . We then predict the conformal weights of affine VOA E 7 + 1 / 2 at level 3, 4, 5. [ABSTRACT FROM AUTHOR]

Recently, Harvey and Wu proposed a suitable Hecke operator for vector-valued SL(2, ℤ) modular forms to connect the characters of different 2d rational conformal field theories (RCFTs). We generalize such an operator to the 2d fermionic RCFTs and call it fermionic Hecke operator. The new Hecke operator naturally maps the Neveu-Schwarz (NS) characters of a fermionic theory to the NS characters of another fermionic theory. Mathematically, it is the natural Hecke operator on vector-valued Γθ modular forms of weight zero. We find it can also be extended to NS ~ and Ramond (R) sectors by combining the characters of the two sectors together. We systematically study the fermionic Hecke relations among 2d fermionic RCFTs with up to five NS characters and find that almost all known supersymmetric RCFTs can be realized as fermionic Hecke images of some simple theories such as supersymmetric minimal models. We also study the coset relations between fermionic Hecke images with respect to c = 12k holomorphic SCFTs. [ABSTRACT FROM AUTHOR]

Flexible photovoltaics have been and will be increasingly in demand in modern and future society in various applications. Searching for ideal flexible photovoltaic technologies that can perfectly meet these expanding demands has long been an active branch of photovoltaic research. Flexible kesterite Cu2ZnSn(S,Se)4 (CZTSSe) has emerged in recent years owning to its great potential to be an abundant, low-cost, stable, and high-efficiency 'green' photovoltaic material that can be widely deployed with the lowest detrimental environmental impact. Here, we review the recent progress with flexible kesterite solar cells in thin-film and monograin technologies, discuss the key challenges and strategies associated with the flexible substrates, and finally provide the future perspectives on further pushing the efficiency toward commercial-competitive levels. [ABSTRACT FROM AUTHOR]

Moyamoya disease (MMD) is a chronic occlusive cerebrovascular disease that can be treated with revascularization. Surgery increases the risk of poor wound healing (PWH) due to the impact on the blood supply to the flap. We aimed to analyze risk factors for PWH in MMD with a complete Y-shaped incision. A total of 125 patients with MMD were enrolled in this prospective observational study. The wounds were assessed and measured on the third and seventh days after surgery. The mean age of these patients was 43.3 ± 10.0 years. The ratio of male to female was 1:1.3. 15 (12.0%) patients had incision complications. 5 patients (4.0%) had redness; 2 patients (1.6%) had swelling; 2 patients (1.6%) had fat necrosis; 3 patients (2.4%) had incision infection; and 3 patients (2.4%) had flap necrosis. Student's t test showed significant differences in BMI (P = 0.040) and fever time (P = 0.050). The standard chi-squared test showed significant differences in incision infection (P = 0.010), suture mode (P = 0.047), and cutting off large branch vessels in the flap (P < 0.001). Multivariate logistic regression analysis suggested that incision infection (P = 0.026, OR 12.958), using a skin stapler (P = 0.030, OR 4.335), cutting off large branch vessels in the flap (P = 0.009, OR 5.227), and BMI (P = 0.027, OR 1.204) were risk factors. The area under the curve for risk factors for PWH on a receiver operating characteristic curve was 0.853. Incision infection, using a skin stapler, higher BMI, and cutting off large branch vessels in the flap are risk factors for PWH. [ABSTRACT FROM AUTHOR]

Kesterite Cu2ZnSn(S, Se)4 (CZTSSe) thin film solar cells have been regarded as one of the most promising thin film photovoltaic technologies, offering a low-cost and environmentally friendly solar energy option. Although remarkable advances have been achieved in kesterite solar cells, the performance gap relative to mature thin film photovoltaic technologies such as CIGSe and CdTe remains large. Significant open-circuit voltage (VOC) deficit has been recognized as the main limiting factor to performance improvement, with undesirable intrinsic defects being a key culprit contributing to the low VOC. To realize the promise inherent in kesterite CZTS to become an earth-abundant alternative to existing thin film photovoltaic technologies with comparable performance, significant research effort has been invested to tackle the challenging defect issues. In this review, recent progress and achievements relevant to engineering improvements to the defect properties of the semiconductor have been examined and summarized. Promising strategies include: (i) manipulating the synthesis process to obtain a desirable reaction pathway and chemical environment; (ii) introducing cation substitution to increase the ionic size difference and supress the related band tailing deep-level defects; (iii) applying post deposition treatment (PDT) with alkaline elements to passivate the detrimental defects. These advances obtained from work on kesterite solar cells may lead to future high performance from this material and may be further extended to other earth-abundant chalcogenide photovoltaic technologies. [ABSTRACT FROM AUTHOR]

Spiro-OMeTAD, one of the most widely used hole-transport materials (HTMs) in optoelectronic devices, typically requires chemical doping with a lithium compound (LiTFSI) to attain sufficient conductivity and efficient hole extraction. However, the doping step requires an activation process that comprises exposure of the blend films to an ambient atmosphere. Additionally, the lithium dopant induces crystallization, and its hygroscopic nature negatively impacts device performance and lifetime. Here we report a facile approach based on the incorporation of a low-cost alkylthiol additive (1-dodecanethiol, DDT) in the spiro-OMeTAD HTM. We discover that DDT provides a more efficient and controllable doping process with significantly reduced doping duration, enabling the HTM to achieve comparable performance before air activation. The coordination between DDT and LiTFSI increases the concentration of dopants in the HTM bulk, reduces their accumulation at interfaces, and enhances the structural integrity of the HTM under wetting, heat and light stress. We fabricate perovskite solar cells using DDT-treated spiro-OMeTAD as the HTM. Our best devices exhibit a certified power conversion efficiency of 23.1%. Furthermore, the devices can retain 90% of peak performance under continuous illumination for 1,000 h. Our findings represent an important step forward in the production of doped spiro-OMeTAD, as well as its reliable application and future device commercialization. The addition of DDT to the spiro-OMeTAD hole transport material enhances the stability of perovskite solar cells to humidity, heat and illumination stress. Fabricated devices exhibit a champion certified power conversion efficiency of 23.1%. Also, the devices could retain 90% of the initial efficiency after 1,000 h of continuous illumination, 97% under moisture stress for 530 h and 91% under 144 h of heat stress. [ABSTRACT FROM AUTHOR]

Photoreforming has been shown to accelerate the H2 evolution rate compared to water splitting due to thermodynamically favorable organic oxidation. In addition, the potential to simultaneously produce solar fuel and value-added chemicals is a significant benefit of photoreforming. To achieve an efficient and economically viable photoreforming process, the selection and design of an appropriate photocatalyst is essential. Carbon nitride is promising as a metal-free photocatalyst with visible light activity, high stability, and low fabrication cost. However, it typically exhibits poor photogenerated charge carrier dynamics, thereby resulting in low photocatalytic performance. Herein, we demonstrate improved carrier dynamics in urea-functionalized carbon nitride with in situ photodeposited Ni cocatalyst (Ni/Urea-CN) for ethanol photoreforming. In the presence of 1 mM Ni2+ precursor, an H2 evolution rate of 760.5 µmol h−1 g−1 and an acetaldehyde production rate of 888.2 µmol h−1 g−1 were obtained for Ni/Urea-CN. The enhanced activity is ascribed to the significantly improved carrier dynamics in Urea-CN. The ability of oxygen moieties in the urea group to attract electrons and to increase the hole mobility via a positive shift in the valence band promotes an improvement in the overall carrier dynamics. In addition, high crystallinity and specific surface area of the Urea-CN contributed to accelerating charge separation and transfer. As a result, the electrons were efficiently transferred from Urea-CN to the Ni cocatalyst for H2 evolution while the holes were consumed during ethanol oxidation. The work demonstrates a means by which carrier dynamics can be tuned by engineering carbon nitride via edge functionalization. [ABSTRACT FROM AUTHOR]

We systemically study the Hecke relations and the c = 8k coset relations among 2d rational conformal field theories (RCFTs) with up to seven characters. We propose that the characters of any 2d RCFT — unitary or non-unitary — satisfying a holomorphic modular linear differential equation (MLDE) can be realized as either a Hecke image or the coset of a Hecke image with respect to a c = 8k theory. Benefited from the recent results on holomorphic modular bootstrap, we check this proposal for all admissible theories with up to five characters. We also find many new interesting Hecke relations. For example, the characters of WZW models (E6)2, (E7)2, ( E 7 1 2 )2 can be realized as the Hecke images T13, T19, T19 of Virasoro minimal models Msub(7, 6), M(5, 4), Meff(13, 2) respectively. Besides, we find the characters associated to the second largest Fisher group Fi23 and the Harada-Norton group HN can be realized as the Hecke images T23, T19 of the product theories Meff(5, 2) ⊗ Meff(7, 2) and Meff(7, 2)⊗2 respectively. Mathematically, our study provides a great many interesting examples of vector-valued modular functions up to rank seven. [ABSTRACT FROM AUTHOR]

Use of university students' educational data for learning analytics has spurred a debate about whether and how to provide students with agency regarding data collection and use. A concern is that students opting out of learning analytics may skew predictive models, in particular if certain student populations disproportionately opt out and biases are unintentionally introduced into predictive models. We investigated university students' propensity to consent to learning analytics through an email prompt, and collected respondents' perceived benefits and privacy concerns regarding learning analytics in a subsequent online survey. In particular, we studied whether and why students' consent propensity differs among student subpopulations bysending our email prompt to a sample of 4,000 students at our institution stratified by ethnicity and gender. 272 students interacted with the email, of which 119 also completed the survey. We identified that institutional trust, concerns with the amount of data collection versus perceived benefits, and comfort with instructors' data use for learning engagement were key determinants in students' decision to participate in learning analytics. We find that students identifying ethnically as Black were significantly less likely to respond and self-reported lower levels of institutional trust. Female students reported concerns with data collection but were also more comfortable with use of their data by instructors for learning engagement purposes. Students' comments corroborate these findings and suggest that agency alone is insufficient; institutional leaders and instructors also play a large role in alleviating the issue of bias. [ABSTRACT FROM AUTHOR]

Given the recent geometrical classification of 6d (1, 0) SCFTs, a major question is how to compute for this large class their elliptic genera. The latter encode the refined BPS spectrum of the SCFTs, which determines geometric invariants of the associated elliptic non-compact Calabi-Yau threefolds. In this paper we establish for all 6d (1, 0) SCFTs in the atomic classification blowup equations that fix these elliptic genera to large extent. The latter fall into two types: the unity and the vanishing blowup equations. For almost all rank one theories, we find unity blowup equations which determine the elliptic genera completely. We develop several techniques to compute elliptic genera and BPS invariants from the blowup equations, including a recursion formula with respect to the number of strings, a Weyl orbit expansion, a refined BPS expansion and an ϵ1, ϵ2 expansion. For higher-rank theories, we propose a gluing rule to obtain all their blowup equations based on those of rank one theories. For example, we explicitly give the elliptic blowup equations for the three higher-rank non-Higgsable clusters, ADE chain of −2 curves and conformal matter theories. We also give the toric construction for many elliptic non-compact Calabi- Yau threefolds which engineer 6d (1, 0) SCFTs with various matter representations. [ABSTRACT FROM AUTHOR]

The building blocks of 6d (1, 0) SCFTs include certain rank one theories with gauge group G = SU(3), SO(8), F4, E6,7,8. In this paper, we propose a universal recursion formula for the elliptic genera of all such theories. This formula is solved from the elliptic blowup equations introduced in our previous paper. We explicitly compute the elliptic genera and refined BPS invariants, which recover all previous results from topological string theory, modular bootstrap, Hilbert series, 2d quiver gauge theories and 4d N = 2 superconformal HG theories. We also observe an intriguing relation between the k-string elliptic genus and the Schur indices of rank k HG SCFTs, as a generalization of Del Zotto-Lockhart's conjecture at the rank one cases. In a subsequent paper, we deal with all other non-Higgsable clusters with matters. [ABSTRACT FROM AUTHOR]

Promoters are critical elements to control gene expression but could behave differently under various growth conditions. Here we report the construction of a genome-wide promoter library, in which each native promoter in Saccharomyces cerevisiae was cloned upstream of a yellow fluorescent protein (YFP) reporter gene. Nine libraries were arbitrarily defined and assembled in bacteria. The resulting pools of promoters could be prepared and transformed into a yeast strain either as centromeric plasmids or integrated into a genomic locus upon enzymatic treatment. Using fluorescence activated cell sorting, we classified the yeast strains based on YFP fluorescence intensity and arbitrarily divided the entire library into 12 bins, representing weak to strong promoters. Several strong promoters were identified from the most active bins and their activities were assayed under different growth conditions. Finally, these promoters were applied to drive the expression of genes in xylose utilization to improve fermentation efficiency. Together, this library could provide a quick solution to identify and utilize desired promoters under user-defined growth conditions. [ABSTRACT FROM AUTHOR]

We establish the elliptic blowup equations for E-strings and M-strings and solve elliptic genera and refined BPS invariants from them. Such elliptic blowup equations can be derived from a path integral interpretation. We provide toric hypersurface construction for the Calabi-Yau geometries of M-strings and those of E-strings with up to three mass parameters turned on, as well as an approach to derive the perturbative prepotential directly from the local description of the Calabi-Yau threefolds. We also demonstrate how to systematically obtain blowup equations for all rank one 5d SCFTs from E-string by blow-down operations. Finally, we present blowup equations for E–M and M string chains. [ABSTRACT FROM AUTHOR]

We propose novel functional equations for the BPS partition functions of 6d (1, 0) SCFTs, which can be regarded as an elliptic version of Göttsche-Nakajima-Yoshioka's K-theoretic blowup equations. From the viewpoint of geometric engineering, these are the generalized blowup equations for refined topological strings on certain local elliptic CalabiYau threefolds. We derive recursion formulas for elliptic genera of self-dual strings on the tensor branch from these functional equations and in this way obtain a universal approach for determining refined BPS invariants. As examples, we study in detail the minimal 6d SCFTs with SU(3) and SO(8) gauge symmetry. In companion papers, we will study the elliptic blowup equations for all other non-Higgsable clusters. [ABSTRACT FROM AUTHOR]

Göttsche-Nakajima-Yoshioka K-theoretic blowup equations characterize the Nekrasov partition function of five dimensional N=1 supersymmetric gauge theories compactified on a circle, which via geometric engineering correspond to the refined topological string theory on SU(N) geometries. In this paper, we study the K-theoretic blowup equations for general local Calabi-Yau threefolds. We find that both vanishing and unity blowup equations exist for the partition function of refined topological string, and the crucial ingredients are the r fields introduced in our previous paper. These blowup equations are in fact the functional equations for the partition function and each of them results in infinite identities among the refined free energies. Evidences show that they can be used to determine the full refined BPS invariants of local Calabi-Yau threefolds. This serves an independent and sometimes more powerful way to compute the partition function other than the refined topological vertex in the A-model and the refined holomorphic anomaly equations in the B-model. We study the modular properties of the blowup equations and provide a procedure to determine all the vanishing and unity r fields from the polynomial part of refined topological string at large radius point. We also find that certain form of blowup equations exist at generic loci of the moduli space. [ABSTRACT FROM AUTHOR]