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We have investigated the performance of the reduced-scaling coupled cluster method based on projected atomic orbitals (PAOs), pair natural orbitals (PNOs), and orbital specific virtuals (OSVs) for the prediction of linear response properties. These methods introduce different degrees of controllable sparsity in the ground-state and perturbed coupled cluster wave functions, leading to localization errors in properties such as dynamic polarizabilities and specific optical rotations. Using a series of chiral test compounds, we find that the inherent costs associated with computing response properties are significantly greater than those for determining the ground-state energy. As the dimensionality of the molecular system increases-from (pseudo)linear structures, such as fluoroalkanes, to cagelike structures, such as β-pinene-the crossover point between canonical-orbital and localized-orbital algorithms increases substantially. Furthermore, both the OSV and PNO methods provide greater reduction in cost (as measured by the size of the double-excitation space) than do PAOs, and PNOs provide the greatest level of sparsity for the systems examined here. Single-excitation truncation induces much larger errors than corresponding doubles truncation due to the fact that the first-order contribution to the one-electron perturbed wave function appears in the singles amplitudes. Both the PNO and OSV methods perform reasonably well for frequency-dependent polarizabilities provided appropriate thresholds are used for the occupation-number and weak-pair cutoffs on which each method depends. Specific rotations, however, are very sensitive to wave function truncation, to the extent that aggressive thresholds can yield the incorrect sign of the rotation, due to the delicate balance of positive and negative wave function contributions to the mixed electric-/magnetic-field response.

In this work we present the first implementation of the incremental scheme for coupled cluster linear-response frequency-dependent dipole polarizabilities. The implementation is fully automated and makes use of the domain-specific basis set approach. The accuracy of the approach is determined on the basis of a test suite of 47 molecules and small clusters. The local approximation in the coupled cluster singles and doubles polarizability exhibits a mean error of 0.02% and a standard deviation of 0.32% when using a third-order incremental expansion. With the proposed approach, it is possible to compute polarizabilities with larger basis sets compared to the canonical implementation and thus it is possible to obtain higher total accuracy. The incremental scheme yields the smallest errors for weakly-bound and quasi-linear systems, while two- and three-dimensional (cage-like) structures exhibit somewhat larger errors as compared to the full test set. Dieser Beitrag ist aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.

Σκύλος φυλής Καυκάσου, ηλικίας 5 μηνών, προσκομίστηκε με ιστορικό διόγκωσης της κοιλίας διάρκειας 20 ημερών και ανορεξίας, κατάπτωσης και εμέτων κατά το τελευταίο 24ωρο. Στην κλινική εξέταση Nπαρατηρήθηκαν κατάπτωση, ασκίτης, ήπια εισπνευστική δύσπνοια και αφυδάτωση. Κατά την εργαστηριακή διερεύνηση διαπιστώθηκαν υπεραμμωνιαιμία, υπολευκωματιναιμία, υπερχολερυθριναιμία, υπογλυκαιμία και υπονατριαιμία. Τα ευρήματα της υπερηχοτομογραφικής διερεύνησης της κοιλίας ήταν μικροηπατία και ελεύθερο περιτοναϊκό υγρό. Στην ερευνητική λαπαροτομή διαπιστώθηκαν πολλαπλές επίκτητες εξωηπατικές αναστομώσεις της πυλαίας φλέβας, συμβατές με πυλαία υπέρταση, ενώ το ήπαρ ήταν μικρό σε μέγεθος και φυσιολογικής υφής και χρώματος. Η ιστοπαθολογική εξέταση του ήπατος ήταν συμβατή με υποαιμάτωση του οργάνου. Με βάση τα παραπάνω αποτελέσματα τέθηκε η διάγνωση της πρωτογενούς υποπλασίας της πυλαίας φλέβας με πυλαία υπέρταση. Η αγωγή που ακολουθήθηκε συμπεριλάμβανε διουρητικά, ηπατοπροστατευτικά και διατροφή χαμηλή σε πρωτεΐνες. Ο σκύλος παραμένει υγιής δύο χρόνια μετά τη διάγνωση. Το περιστατικό αυτό, αναδεικνύει την καλή μακροχρόνια πρόγνωση που έχουν τα περιστατικά με πρωτογενή υποπλασία της πυλαίας φλέβας και πυλαία υπέρταση στο σκύλο, γεγονός που δικαιολογεί την συντηρητική θεραπευτική αντιμετώπιση και την αποθάρρυνση της διενέργειας ευθανασίας., A 5-month old Caucasian dog was presented with a 20-day history of abdominal distention along with inappetance, depression and vomiting of 24-hour duration. Physical examination findings included depression, ascites, mild inspiratory dyspnea and dehydration. Clinicopathological evaluation revealed hyperammonemia, hypoalbuminemia, hyperbilirubinemia, hypoglycemia and hyponatremia. Μicrohepatia and free abdominal fluid was detected with abdominal ultrasonography. During exploratory laparotomy, multiple acquired portosystemic collateral vessels were found, indicative of portal hypertension, along with a small liver of normal color and texture. Liver histopathology included features consistent with liver hypoperfusion. These findings supported the diagnosis of primary portal vein hypoplasia with portal hypertension. The animal recovered uneventfully postoperatively and was discharged with diuretics, hepatoprotectants and a low-protein diet and remains healthy two years after diagnosis. This case underscores that a favorable prognosis may be anticipated in cases of primary portal vein hypoplasia with portal hypertension, thus, justifying the long-term conservative management instead of considering euthanasia.

In 1965, the specialty of paediatric nephrology was in its infancy. Following the development of a landmark collaborative research study, the International Study of Kidney Disease in Childhood in the mid-1960s, the first specialist societies were formed: the European Society of Pediatric Nephrology in 1967 and the American Society of Pediatric Nephrology in 1969. The extraordinary improvements in care delivered to children with kidney disease over the past 50 years are too broad to cover in any one paper. They traverse the spectrum of diagnosis, classification, therapeutics, social well-being and transition to adult care. We have selected four case scenarios to highlight these changes in key areas of paediatric nephrology: post-streptococcal glomerulonephritis, nephrotic syndrome, haemolytic uraemic syndrome and neonatal dialysis and childhood transplantation.

Available from: EC 090 032.

PSI4 is an ab initio electronic structure program providing methods such as Hartree Fock, density functional theory, configuration interaction, and coupled-cluster theory. The 1.1 release represents a major update meant to automate complex tasks, such as geometry optimization using complete basis-set extrapolation or focal-point methods. Conversion of the top-level code to a Python module means that PRI-can now be used in complex workflows alongside other Python tools. Several new features have been added with the aid of libraries providing easy access to techniques such as density fitting, Cholesky decomposition, and Laplace denominators. The build system has been completely rewritten to simplify interoperability with independent, reusable software components for quantum chemistry. Finally, a wide range of new theoretical methods and analyses have been added to the code base, including functional-group and open-shell symmetry adapted perturbation theory, density-fitted coupled cluster with frozen natural orbitals, orbital-optimized perturbation and coupled-cluster methods (e.g., OO-MP2 and OO-LCCD), density-fitted multiconfigurational self-consistent field, density cumulant functional theory, algebraic-diagrammatic construction excited states, improvements to the geometry optimizer, and the "X2C" approach to relativistic corrections, among many other improvements.

Advances in technology has allowed us to demand for high speed and low power devices in modern chips. These transistors are scaled down and examined with multi-gate architecture in order to improve electrostatic control over the channel and reduce power consumption. A novel dual-gate gate-all-around (GAA) junctionless nanowire transistor (JNT) is addressed in this work. Using TCAD device modeling, we report a process variability analysis and explored the device characteristics. A cylindrical nanowire with a channel length of 10 nm and a diameter of 5 nm is employed to study the process sensitivity of the device. A 1 nm thick HfO2 gate is used as a dielectric material. Analysis from deep depletion to strong accumulation mode with a 2e19 cm−3 n-type channel doping (Vds = 0.8V and T = 300 K) is reported. The dual-gate GAA JNT shows an improved electrical behavior with a variation to channel doping, channel diameter, channel length and oxide thickness. It also has an enhanced short channel behavior such as high Ion/Ioff (>106), good sub threshold slope (∼68 mV/decade) and low drain induced barrier lowering (∼8mV/V) compared to conventional inversion mode transistors and regular nanowire GAA devices that makes the device a candidate for energy efficiency improvements.

Advances in short channel transistor technology has allowed the emergence of these devices in modern chips. These transistors experience many different types of Short Channel Effects (SCE) that are addressed in this work. Using TCAD simulations, we report a new and effective technique to reduce SCE in a novel dual-gate silicon nanowire Gate-All-Around (GAA) junctionless transistor. A channel length of 10 nm and a diameter of 5 nm is employed to mitigate SCE in terms of Subthreshold Slope (SS), Leakage current (Ioff) and Drain Induced Barrier Lowering (DIBL). A 1 nm thick HfO2 gate is used as a dielectric material. Analysis from deep depletion to strong accumulation mode with 2e19 cm−3 n-type channel doping (Vds = 0.8V and T = 300 K) is reported. The dual-gate GAA junctionless nanowire transistor shows improved electrical characteristics such as high Ion/Ioff (>106), good subthreshold slope (∼68 mV/decade) and low drain induced barrier lowering (∼8mV/V) compared to conventional inversion mode transistors and single nanowire GAA devices that makes the device a candidate for energy efficiency improvements.

BACKGROUND: The calcium-sensing receptor regulates the secretion of parathyroid hormone in response to changes in extracellular calcium concentrations, and mutations that result in a loss of function of the receptor are associated with familial hypocalciuric hypercalcemia. Mutations involving a gain of function have been associated with hypocalcemia in two kindreds. We examined the possibility that the latter type of mutation may result in a phenotype of familial hypocalcemia with hypercalciuria. METHODS: We studied six kindreds given a diagnosis of autosomal dominant hypoparathyroidism on the basis of their hypocalcemia and normal serum parathyroid hormone concentrations, a combination that suggested a defect of the calcium-sensing receptor. The hypocalcemia was associated with hypercalciuria, and treatment with vitamin D resulted in increased hypercalciuria, nephrocalcinosis, and renal impairment. Mutations in the calcium-sensing-receptor gene were identified by DNA-sequence analysis and expressed in human embryonic kidney cells (HEK-293). RESULTS: Five heterozygous missense mutations (Asn118Lys, Phe128Leu, Thr151Met, Glu191Lys, and Phe612Ser) were detected in the extracellular domain of the calcium-sensing-receptor gene and shown to cosegregate with the disease. Analysis of the functional expression of three of the mutant receptors in HEK-293 cells demonstrated shifts in the dose-response curves so that the extracellular calcium concentrations needed to produce half-maximal increases in total inositol phosphate in the cells were significantly (P=0.02 to P

The use of various mathematical models to represent saturation in a synchronous machine is considered, with emphasis on quadrature axis saturation. Calculated transient-response results are compared in order to find an accurate and computationally economical method of allowing for saturation.