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The present work intends to join and respond to the excellent and thoroughly documented rovibrational study of X. G. Wang and T. Carrington, Jr. [J. Chem. Phys. 154, 124112 (2021)] that used an approach tailored for floppy dimers with an analytic dimer Hamiltonian and a non-product basis set including Wigner D functions. It is shown in the present work that the GENIUSH black-box-type rovibrational method can approach the performance of the tailor-made computation for the example of the floppy methane–water dimer. Rovibrational transition energies and intensities are obtained in the black-box-type computation with a twice as large basis set and in excellent numerical agreement in comparison with the more efficient tailor-made approach. [ABSTRACT FROM AUTHOR]

The complex of a methane molecule and a fluoride anion represents a 12-dimensional (12D), four-well vibrational problem with multiple large-amplitude motions, which has challenged the quantum dynamics community for years. The present work reports vibrational band origins and tunneling splittings obtained in a full-dimensional variational vibrational computation using the GENIUSH program and the Smolyak quadrature scheme. The converged 12D vibrational band origins and tunneling splittings confirm complementary aspects of the earlier full- and reduced-dimensionality studies: (1) the tunneling splittings are smaller than 0.02 cm−1; (2) a single-well treatment is not sufficient (except perhaps the zero-point vibration) due to a significant anharmonicity over the wells; and thus, (3) a full-dimensional treatment appears to be necessary. The present computations extend to a higher energy range than earlier work, show that the tunneling splittings increase upon vibrational excitation of the complex, and indicate non-negligible "heavy-atom" tunneling. [ABSTRACT FROM AUTHOR]

Methodological progress is reported in the challenging direction of a black-box-type variational solution of the (ro)vibrational Schrödinger equation applicable to floppy, polyatomic systems with multiple large-amplitude motions. This progress is achieved through the combination of (i) the numerical kinetic-energy operator (KEO) approach of Mátyus et al. [J. Chem. Phys. 130, 134112 (2009)] and (ii) the Smolyak nonproduct grid method of Avila and Carrington, Jr. [J. Chem. Phys. 131, 174103 (2009)]. The numerical representation of the KEO makes it possible to choose internal coordinates and a body-fixed frame best suited for the molecular system. The Smolyak scheme reduces the size of the direct-product grid representation by orders of magnitude, while retaining some of the useful features of it. As a result, multidimensional (ro)vibrational states are computed with system-adapted coordinates, a compact basis- and grid-representation, and an iterative eigensolver. Details of the methodological developments and the first numerical applications are presented for the CH4·Ar complex treated in full (12D) vibrational dimensionality. [ABSTRACT FROM AUTHOR]

In this paper, we demonstrate that it is possible to apply collocation to compute vibrational energy levels of a five-atom molecule using an exact kinetic energy operator (with cross terms and coordinatedependent coefficients). This is made possible by using (1) a pruned basis of products of univariate functions; (2) a Smolyak grid made from nested sequences of grids for each coordinate; (3) a collocation method that obviates the need to solve a generalized eigenvalue problem; (4) an efficient sequential transformation between the (nondirect product) grid and the (nondirect product) basis representations; and (5) hierarchical univariate functions that make it possible to avoid storing large intermediate vectors. The accuracy of the method is confirmed by computing 500 vibrational energy levels of methane. [ABSTRACT FROM AUTHOR]

In this paper, we improve the collocation method for computing vibrational spectra that was presented in the work of Avila and Carrington, Jr. [J. Chem. Phys. 143, 214108 (2015)]. Known quadrature and collocation methods using a Smolyak grid require storing intermediate vectors with more elements than points on the Smolyak grid. This is due to the fact that grid labels are constrained among themselves and basis labels are constrained among themselves. We show that by using the so-called hierarchical basis functions, one can significantly reduce the memory required. In this paper, the intermediate vectors have only as many elements as the Smolyak grid. The ideas are tested by computing energy levels of CH2NH. [ABSTRACT FROM AUTHOR]

In this paper, we improve the collocation method for computing vibrational spectra that was presented in Avila and Carrington, Jr. [J. Chem. Phys. 139, 134114 (2013)]. Using an iterative eigensolver, energy levels and wavefunctions are determined from values of the potential on a Smolyak grid. The kinetic energy matrix-vector product is evaluated by transforming a vector labelled with (nondirect product) grid indices to a vector labelled by (nondirect product) basis indices. Both the transformation and application of the kinetic energy operator (KEO) scale favorably. Collocation facilitates dealing with complicated KEOs because it obviates the need to calculate integrals of coordinate dependent coefficients of differential operators. The ideas are tested by computing energy levels of HONO using a KEO in bond coordinates. [ABSTRACT FROM AUTHOR]

In this paper we propose and test a method for computing numerically exact vibrational energy levels of a molecule with six atoms. We use a pruned product basis, a non-product quadrature, the Lanczos algorithm, and the exact normal-coordinate kinetic energy operator (KEO) with the πtμπ term. The Lanczos algorithm is applied to a Hamiltonian with a KEO for which μ is evaluated at equilibrium. Eigenvalues and eigenvectors obtained from this calculation are used as a basis to obtain the final energy levels. The quadrature scheme is designed, so that integrals for the most important terms in the potential will be exact. The procedure is tested on C2H4. All 12 coordinates are treated explicitly. We need only ∼1.52 × 108 quadrature points. A product Gauss grid with which one could calculate the same energy levels has at least 5.67 × 1013 points. [ABSTRACT FROM AUTHOR]

In this paper we propose a new quadrature scheme for computing vibrational spectra and apply it, using a Lanczos algorithm, to CH3CN. All 12 coordinates are treated explicitly. We need only 157'419'523 quadrature points. It would not be possible to use a product Gauss grid because 33 853 318 889 472 product Gauss points would be required. The nonproduct quadrature we use is based on ideas of Smolyak, but they are extended so that they can be applied when one retains basis functions θn1(r1)...θnD(rD) that satisfy the condition α1n1 + ··· + αDnD <= b, where the αk are integers. We demonstrate that it is possible to exploit the structure of the grid to efficiently evaluate the matrix-vector products required to use the Lanczos algorithm. [ABSTRACT FROM AUTHOR]

The size of the quadrature grid required to compute potential matrix elements impedes solution of the vibrational Schrödinger equation if the potential does not have a simple form. This quadrature grid-size problem can make computing (ro)vibrational spectra impossible even if the size of the basis used to construct the Hamiltonian matrix is itself manageable. Potential matrix elements are typically computed with a direct product Gauss quadrature whose grid size scales as ND, where N is the number of points per coordinate and D is the number of dimensions. In this article we demonstrate that this problem can be mitigated by using a pruned basis set and a nonproduct Smolyak grid. The constituent 1D quadratures are designed for the weight functions important for vibrational calculations. For the SF6 stretch problem (D=6) we obtain accurate results with a grid that is more than two orders of magnitude smaller than the direct product Gauss grid. If D>6 we expect an even bigger reduction. [ABSTRACT FROM AUTHOR]

Phosgene (Cl2C=O) is extremely poisonous, underscoring the importance of accurate infrared detection. Here, the computed vibrational energy levels of phosgene are reported for the first time from a six-dimensional potential energy surface (PES) that was constructed from 25,000 single-point energy computations at the CCSD(T)/cc-pVTZ level of theory. The computed points were fit using a neural network method, and the resulting PES was employed in the determination of vibrational energies and wavefunctions. Bond coordinates were utilised in conjunction with a collocation method to minimise problems that arise from the complicated nature of the kinetic energy operator. The collocation method makes possible the computation of energy levels without integral evaluation, and without the need to solve a generalised eigenvalue problem. Moreover, it is built on a nondirect product-pruned basis that is much smaller than the direct product basis that would be required to obtain the same accuracy. [ABSTRACT FROM AUTHOR]

In this paper we demonstrate that when one prunes a product basis for CH 3 CN using g 1 ( n 1 ) + g 2 ( n 2 ) + ⋯ + g D ( n D ) ⩽ b and appropriate g c ( n c ) functions it is possible obtain many converged energy levels using a basis that is smaller than the basis obtained with the pruning condition α 1 n 1 + α 2 n 2 + ⋯ + α D n D ⩽ b (Avila and Carrington, 2011) and comparable to the basis built using residual vectors (Garnier et al., 2016). Importantly, the pruning condition g 1 ( n 1 ) + g 2 ( n 2 ) + ⋯ + g D ( n D ) ⩽ b obviates the need to store a Hamiltonian matrix and facilitates the use of iterative eigensolvers because it is compatible with efficient matrix–vector products. Moreover, it may be used in conjunction with a nondirect product quadrature and therefore allows one to use a potential energy surface that is not a simple sum of products. [ABSTRACT FROM AUTHOR]

Anthrax toxin receptors act as molecular clamps or switches that control anthrax toxin entry, pH-dependent pore formation, and translocation of enzymatic moieties across the endosomal membranes. We previously reported that reduction of the disulfide bonds in the immunoglobulin-like (Ig) domain of the anthrax toxin receptor 2 (ANTXR2) inhibited the function of the protective antigen (PA) pore. In the present study, the disulfide linkage in the Ig domain was identified as Cys255-Cys279 and Cys230-Cys315. Specific disulfide bond deletion mutants were achieved by replacing Cys residues with Ala residues. Deletion of the disulfide bond C255-C279, but not C230-C315, inhibited the PA pore-induced release of the fluorescence dyes from the liposomes, suggesting that C255-C279 is essential for PA pore function. Furthermore, we found that deletion of C255-C279 did not affect PA prepore-to-pore conversion, but inhibited PA pore membrane insertion by trapping the PA membrane-inserting loops in proteinaceous hydrophobic pockets. Fluorescence spectra of Trp59, a residue adjacent to the PA-binding motif in von Willebrand factor A (VWA) domain of ANTXR2, showed that deletion of C255-C279 resulted in a significant conformational change on the receptor ectodomain. The disulfide deletion-induced conformational change on the VWA domain was further confirmed by single-particle 3D reconstruction of the negatively stained PA-receptor heptameric complexes. Together, the biochemical and structural data obtained in this study provides a mechanistic insight into the role of the receptor disulfide bond C255-C279 in anthrax toxin action. Manipulation of the redox states of the receptor, specifically targeting to C255-C279, may become a novel strategy to treat anthrax. [ABSTRACT FROM AUTHOR]

Gam1, an early gene product of an avian adenovirus, is essential for viral replication. Gam1 is the first viral protein found to globally inhibit cellular SUMOylation, a critical posttranslational modification that alters the function and cellular localization of proteins. The interaction details at the interface between Gam1 and its cellular targets remain unclear due to the lack of structural information. Although Gam1 has been previously characterized, the purity of the protein was not suitable for structural investigations. In the present study, the gene of Gam1 was cloned and expressed in various bacterial expression systems to obtain pure and soluble recombinant Gam1 protein for in vitro functional and structural studies. While Gam1 was insoluble in most expression systems tested, it became soluble when it was expressed as a fusion protein with trigger factor (TF), a ribosome associated bacterial chaperone, under the control of a cold shock promoter. Careful optimization indicates that both low temperature induction and the chaperone function of TF play critical roles in increasing Gam1 solubility. Soluble Gam1 was purified to homogeneity through sequential chromatography techniques. Monomeric Gam1 was obtained via size exclusion chromatography and analyzed by dynamic light scattering. The SUMOylation inhibitory function of the purified Gam1 was confirmed in an in vitro assay. These results have built the foundation for further structural investigations that will broaden our understanding of Gam1’s roles in viral replication. [ABSTRACT FROM AUTHOR]

The automated development of a new ab initio full-dimensional potential energy surface (PES) is reported for the CH4·F− complex using the Robosurfer program package. The new potential provides a near-spectroscopic quality description over a broad configuration range including the methane-ion dissociation, as well as isolated methane vibrations. In particular, it improves upon the earlier [Czakó, Braams, Bowman (2008)] PES over intermediate methane-fluoride distances. Full-dimensional (12D) variational vibrational computations using the new PES and the GENIUSH-Smolyak algorithm show that tunnelling splittings larger than 0.1 cm−1 appear below the top of the interconversion barrier of the four equivalent minima of the complex. [ABSTRACT FROM AUTHOR]

Vibrational states of the formic acid molecule are converged using the GENIUSH–Smolyak approach and the potential energy surface taken from Tew and Mizukami (2016). The quantum nuclear motion is described by using the cis - trans torsional coordinate and eight curvilinear normal coordinates defined with respect to an instantaneous reference configuration changing as a function of the torsional degree of freedom. Harmonic oscillator basis functions are used for the curvilinear normal coordinates, a Fourier basis for the torsional coordinate, and a simple basis pruning condition is combined with a Smolyak integration grid. Trans, cis , and delocalized vibrational states are reported up to and slightly beyond the isomerization barrier. [Display omitted] • Variational vibrational methodology is developed for molecules with large-amplitude motion(s). • Curvilinear normal coordinates are relaxed along the large-amplitude motion. • Basis and grid pruning attenuate the exponential scale-up of exact quantum dynamics methods. • Vibrational states up to and beyond the cis - trans isomerization barrier of formic acid. [ABSTRACT FROM AUTHOR]

B Introduction: b With the ongoing COVID pandemic, physicians are being questioned about potential serious side effects & the risk of these developing. On day 4, the PLT count was 1000 despite multiple transfusions and ongoing steroid therapy and she had a worsening headache and new onset rectal bleeding. B Discussion: b Current recommendations for ITP are glucocorticoids and IVIG as the first line of therapy for minor bleeding w/ platelet count < 20,000. [Extracted from the article]

ABSTRACT In the 1960s, when Dr. Belding Scribner discovered how to accomplish the process of dialysis in a repeated way, he could not imagine that in solving such a problem others as or more difficult would appear. Given the technological progress and the impossibility of assisting all patients through the most modern methods, the medical doctor often finds himself faced with the moral dilemma of choosing which patient in the waiting list will receive the treatment. This same dilemma is amplified in the case of organ transplants. Professionals, students, professors of the juridical and health fields, and the population in general, were interviewed as a means of documenting the moral concepts and opinions surrounding this problem. In the reality in which we find ourselves, it seems to us that deciding who lives, and the responsibility for all the events that culminate in such decisions, is still a subject left open to discussion. [ABSTRACT FROM AUTHOR]

Molecular rotation, vibration, internal rotation, isomerization, tunneling, intermolecular dynamics of weakly and strongly interacting systems, intra-to-inter-molecular energy transfer, hindered rotation and hindered translation over surfaces are important types of molecular motions. Their fundamentally correct and detailed description can be obtained by solving the nuclear Schrödinger equation on a potential energy surface. Many of the chemically interesting processes involve quantum nuclear motions which are 'delocalized' over multiple potential energy wells. These 'large-amplitude' motions in addition to the high dimensionality of the vibrational problem represent challenges to the current (ro)vibrational methodology. A review of the quantum nuclear motion methodology is provided, current bottlenecks of solving the nuclear Schrödinger equation are identified, and solution strategies are reviewed. Technical details, computational results, and analysis of these results in terms of limiting models and spectroscopically relevant concepts are highlighted for selected numerical examples. [ABSTRACT FROM AUTHOR]

In this paper, we present a new collocation method for solving the Schroedinger equation. Collocation has the advantage that it obviates integrals. All previous collocation methods have, however, the crucial disadvantage that they require solving a generalized eigenvalue problem. By combining Lagrange-like functions with a Smolyak interpolant, we device a collocation method that does not require solving a generalized eigenvalue problem. We exploit the structure of the grid to develop an efficient algorithm for evaluating the matrix-vector products required to compute energy levels and wavefunctions. Energies systematically converge as the number of points and basis functions are increased. [ABSTRACT FROM AUTHOR]

In this paper, we present new basis pruning schemes and compatible quadrature grids for solving the vibrational Schrödinger equation. The new basis is designed to include the product basis functions coupled by the largest terms in the potential and important for computing low-lying vibrational levels. To solve the vibrational Schrödinger equation without approximating the potential, one must use quadrature to compute potential matrix elements. For a molecule with more than five atoms, the use of iterative methods is imperative, due to the size of the basis and the quadrature grid. When using iterative methods in conjunction with quadrature, it is important to evaluate matrix-vector products by doing sums sequentially. This is only possible if both the basis and the grid have structure. Although it is designed to include only functions coupled by the largest terms in the potential, the new basis and also the quadrature for doing integrals with the basis have enough structure to make efficient matrix-vector products possible. When results obtained with a multimode approximation to the potential are accurate enough, full-dimensional quadrature is not necessary. Using the quadrature methods of this paper, we evaluate the accuracy of calculations made by making multimode approximations. [ABSTRACT FROM AUTHOR]

Patients are most often asymptomatic, but reports have been made were patients present symptomatically after PCE. Patient was admitted to the ICU for mechanical ventilation and open cardiac surgery to remove cement from the lungs was considered, but patients status continued to deteriorate in the following 24 hours. Although most patients remain asymptomatic according to different authors, it has been reported cases in which patients develop symptoms months, and even until 10 years after procedure. [Extracted from the article]

Background Migration of dental implants into the maxillary sinus is an uncommon, but increasingly reported complication. Implant migration may result from initial lack of primary stability, intrasinusal and nasal pressure changes, autoimmune reaction to the implant or incorrect distribution of occlusal forces. This retrospective study aims at analyzing the factors that may influence implant migration into the maxillary sinus cavity. Material and methods Fourteen patients presenting a total 15 implants that migrated into the maxillary sinus were recruited. Diagnosis of this complication was based on imaging techniques, such as cone beam computerized tomography scan and panoramic radiography. Clinical data were recorded in all cases and processed for statistical analysis. Results ABH was below 6 mm in the majority of cases. However, almost 50% of the patients did not receive any site preparation treatment prior to implant insertion. Five patients (33.3%) were treated by osteotome techniques, but only one of them had bone grafting. Therefore, 73.3% of sites did not receive any biomaterial to increase available bone height. The most common complication-associated factors found on this study were related to implant design (cylindrical), implant dimension (diameter), implant restoration/rehabilitation method (partial removable denture), site-specific anatomy (initial residual bone height between 5 and 6.9 mm), demographics (age), and biomaterials. Conclusion Patient selection and proper treatment planning, as well as the application of the appropriate sinus augmentation technique, are critical aspects that should be controlled to minimize the risk of implant migration into the maxillary sinus cavity. [Correction added after online publication August 17 2011: The Conclusion was revised to provide better clarity to the reader.] [ABSTRACT FROM AUTHOR]

Introduction: Maxillary sinus augmentation is a predictable implant site development technique, although several local and systemic factors may influence outcomes. The aim of this study was to evaluate healing patterns and bone remodeling activity following the use of two different graft mixtures for maxillary sinus augmentation. Materials and methods: Patients in need of maxillary sinus augmentation were randomly assigned to two different groups. A graft mixture using a 50% autologous bone (AB) to 50% anorganic bovine bone (ABB) ratio was used in group 1, while a 20% AB to 80% ABB ratio was utilized for group 2. After a 6‐month healing period, bone core biopsies were harvested for histological, histomorphometrical, and immunohistochemical analyses. Results: Twenty‐eight subjects participated in this study. No statistically significant differences were found between groups in regards to vital bone and non‐mineralized tissue proportions. Higher number of osteoid lines (18.05 ± 10.06 in group 1 vs. 9.01 ± 7.53 in group 2; P=0.023) and higher cellularity, particularly regarding the number of osteocytes (631.85 ± 607.98 in group 1 vs. 219.08 ± 103.26 in group 2; P=0.002), were observed in specimens from group 1. Differences in expression patterns of osteopontin and tartrate‐resistant acid phosphatase were also detected between groups. Conclusion: AB to ABB ratio appears to influence bone remodeling patterns and cell content following maxillary sinus augmentation procedures. Similar proportion of vital bone was found in specimens obtained from both groups. More cellular presence was observed in samples containing higher proportions of AB. To cite this article: 
Galindo‐Moreno P, Moreno‐Riestra I, Avila G, Padial‐Molina M, Paya JA, Wang H‐L, O'Valle F. Effect of anorganic bovine bone to autogenous cortical bone ratio upon bone remodeling patterns following maxillary sinus augmentation.
Clin. Oral Impl. Res. 22, 2011; 857–864.
doi: 10.1111/j.1600‐0501.2010.02073.x [ABSTRACT FROM AUTHOR]

Pneumothorax detection is challenging, and X rays may take several hours to be reviewed by a radiologist. Building a reliable model to diagnose pneumothoraces may alert radiologists to review X rays in a more timely manner, and will monitor the progression of the disease by noting changes occurring over the course of multiple chest x-rays that might otherwise be overlooked Because there were many more images involving no pneumothorax than cases with pneumothorax, random subsampling of the images with no pneumothorax was performed. [Extracted from the article]

Abstract: Hsp90 is a ubiquitous molecular chaperone that plays a key role in the malignant development of hormone-dependent pathologies such as cancer. An important role for Hsp90 is to facilitate the stable binding of steroid hormones to their respective receptors enabling the ligand-based signal to be carried to the nucleus and ultimately resulting in the up-regulation of gene expression. Along with Hsp90, this dynamic and transient process also involves the recruitment of additional proteins and co-chaperones that add further stability to the mature receptor–chaperone complex. In the work presented here, we describe four new protocols for the bacterial over-expression and column chromatographic purification of the human p23, FKBP52, HOP and SGTα proteins. Each of these proteins plays a distinct role in the steroid hormone receptor regulatory cycle. Affinity, ion-exchange and size-exclusion techniques were used to produce target yields greater than 50mg/L of cultured media, with each purified sample reaching near absolute sample homogeneity. These results reveal a reliable system for the production of p23, FKBP52, HOP and SGTα substrate proteins for use in the investigation of the Hsp90-associated protein interactions of the steroid hormone receptor cycle. [ABSTRACT FROM AUTHOR]