Bithiophenesulfonamide Building Block for π-Conjugated Donor-Acceptor Semiconductors.

We report here π-conjugated small molecules and polymers based on the new π-acceptor building block, bithiophenesulfonamide (BTSA). Molecular orbital computations and optical, electrochemical, and crystal structure analyses illuminate the architecture and electronic structure of the BTSA unit versus other acceptor building blocks. Field-effect transistors and photovoltaic cells demonstrate that BTSA is a promising unit for the construction of π-conjugated semiconducting materials.

Metal-free tetrathienoacene sensitizers for high-performance dye-sensitized solar cells.

A new series of metal-free organic chromophores (TPA-TTAR-A (1), TPA-T-TTAR-A (2), TPA-TTAR-T-A (3), and TPA-T-TTAR-T-A (4)) are synthesized for application in dye-sensitized solar cells (DSSC) based on a donor-π-bridge-acceptor (D-π-A) design. Here a simple triphenylamine (TPA) moiety serves as the electron donor, a cyanoacrylic acid as the electron acceptor and anchoring group, and a novel tetrathienoacene (TTA) as the π-bridge unit. Because of the extensively conjugated TTA π-bridge, these dyes exhibit high extinction coefficients (4.

Electron pairing in designer materials: a novel strategy for a negative effective Hubbard U.

We propose a set of design rules with a model Hamiltonian that allows electrons to form attracting pairs through the exploitation of a new combination of resonant band alignment and Coulombic repulsion. The pair bands and single particle bands in various lattices are calculated and compared in energy, and regions of net attraction are identified. This work provides guidelines for the construction of molecular systems, nanocrystals, and nanoparticle arrays with the potential for superconductivity.

Substantial photovoltaic response and morphology tuning in benzo[1,2-b:6,5-b']dithiophene (bBDT) molecular donors.

The influence of solubilizing substituents on the photovoltaic performance and thin-film blend morphology of new benzo[1,2-b:6,5-b']dithiophene (bBDT) based small molecule donor semiconductors is investigated. Solar cells based on bBDT(TDPP)2-PC71BM with two different types of side chains exhibit high power conversion efficiencies, up to 5.53%.

Bithiopheneimide-dithienosilole/dithienogermole copolymers for efficient solar cells: information from structure-property-device performance correlations and comparison to thieno[3,4-c]pyrrole-4,6-dione analogues.

Rational creation of polymeric semiconductors from novel building blocks is critical to polymer solar cell (PSC) development. We report a new series of bithiopheneimide-based donor-acceptor copolymers for bulk-heterojunction (BHJ) PSCs. The bithiopheneimide electron-deficiency compresses polymer bandgaps and lowers the HOMOs--essential to maximize power conversion efficiency (PCE).

The movements of limb segments and joints during locomotion in African and Asian elephants.

As the largest extant terrestrial animals, elephants do not trot or gallop but can move smoothly to faster speeds without markedly changing their kinematics, yet with a shift from vaulting to bouncing kinetics. To understand this unusual mechanism, we quantified the forelimb and hindlimb motions of eight Asian elephants (Elephas maximus) and seven African elephants (Loxodonta africana). We used 240 Hz motion analysis (tracking 10 joint markers) to measure the flexion/extension angles and angular velocities of the limb segments and joints for 288 strides across an eightfold range of speeds (0.

Subcapsular hepatic hematoma with right hepatic vein thrombosis: a complication of shock wave lithotripsy.

Extracorporeal shock wave lithotripsy (ESWL) is a well-established, safe and effective therapeutic modality for surgical treatment of urolithiasis. Hematoma is a rare complication of ESWL and, when it occurs, typically involves the kidney. We report the case of a 71-year-old woman who developed severe, persistent abdominal pain after ESWL for a 9-mm stone at the ureteropelvic junction.

Adolescent psychopathy features: 6-year temporal stability and the prediction of externalizing symptoms during the transition to adulthood.

This study investigated the 6-year stability and predictive validity of adolescent psychopathy features during the transition to young adulthood. It represents one of the longest outcome studies of youth psychopathy to date, and therefore addresses a primary criticism of the research area (i.e.

Associations of phenylthiocarbamide tasting to alcohol problems and family history of alcoholism differ by gender.

Past research associating phenylthiocarbamide/propylthiouracil (PTC/PROP) taste status with alcoholism has produced equivocal results. Some have found higher proportions of nontasters among those with a family history of alcoholism than controls, whereas others have not. The purpose of this study was to investigate the relationship between PTC taste status, alcohol problems, and family history of alcoholism.

Trait affectivity and non-referred adolescent conduct problems.

This study examined for profiles of positive trait affectivity (PA) and negative trait affectivity (NA) associated with adolescent conduct problems. Prior trait affectivity research has been relatively biased toward the assessment of adults and internalizing symptomatology. Consistent with recent developmental modeling of antisocial behavior, this study proposed that conduct problems are uniquely associated with 2 PA-NA profiles (i.

The relation between salivary cortisol, callous-unemotional traits, and conduct problems in an adolescent non-referred sample.

Background: Previous research has suggested that adult psychopathic behavior and child callous-unemotional (CU) traits are uniquely related to low emotional reactivity. Salivary cortisol is a promising biological measure of emotional reactivity that has been relatively overlooked in research on CU traits and antisocial behavior. The current study examined for gender differences in the relation between resting salivary cortisol levels and CU traits in a non-referred adolescent sample.