Neurosyphilis and penicillin levels in cerebrospinal fluid

Because neurosyphilis may progress despite therapy with the recommended penicillin regimens, 15 subjects with positive tests for syphilis in the serum and cerebrospinal fluid (CSF) were studied. All of these patients had CSF pleocytosis. Two received penicillin G (5 and 10 million units per day intravenously, respectively) and 13 received benzathine penicillin G, 3.6 million units per week intramuscularly; treatment lasted four weeks. During intravenous and after intramuscular penicillin therapy, a spinal tap was performed on all subjects; later, assays were done. Of two patients who received intravenous penicillin G, one had 0.3 mug/ml and the other had 2.4 mug/ml penicillin in the CSF. Twelve of 13 patients who received benzathine penicillin G had no detectable penicillin in the CSF; one patient had 0.1 mug/ml penicillin in the CSF.     

Characterization of northern pintail (Anas acuta) ejaculate and the effect of sperm preservation on fertility

Northern pintail duck semen and sperm traits were characterized, and the fertility of cold-stored spermatozoa was investigated using artificial insemination. Excellent quality ejaculates containing high proportions of motile spermatozoa were collected from drakes within 20 s by a massage technique. Semen was collected in Beltsville poultry semen extender, pooled and cold-stored (4 degrees C) for 0, 24, 48 or 72 h. Hens were inseminated with 100 microl twice a week, and eggs were assessed for fertilization and hatch success. Fertilization success was similar (P > 0.05) for semen cold-stored for 0 (51.6%), 24 (51.5%), 48 (41.1%) and 72 h (22.3%; P > 0.05). Similar (P > 0.05) percentages of fertilized eggs hatched to live offspring (73.1, 71.4, 87.0 and 80.0%, respectively). Fresh semen was also equilibrated with 1 or 4% dimethylsulphoxide or glycerol, and cryopreserved at the following rates: (1) approximately 60 degrees C min(-1) (in liquid nitrogen [LN(2)] vapour) for 10 min; (2) 1 degrees C min(-1) to -20 degrees C, LN(2) vapour for 10 min; and (3) 1 degrees C min(-1) to -35 degrees C, all followed by immersion in LN(2). After thawing for 30 s at 37 degrees C or 20 min at 4 degrees C, sperm motility and viability were assessed. The highest numbers of motile spermatozoa were recovered after slow-fast freezing (2) and thawing at 0 degrees C (P < 0.05), but survival was inadequate to allow artificial insemination. Nonetheless, cold storage provides an effective means of short-term storage with no loss of fertility in this waterfowl species.     

Age and gender differences in oppositional behavior and conduct problems: A cross-sectional household study of middle childhood and adolescence.

Behavior problems among youths cannot be understood without explaining their age and gender differences, but age and gender differences cannot be explained until they have been accurately described. In a household survey of 1,285 youths aged 9 to 17 years, there were no gender differences in oppositional behavior, but aggression, property offenses, and status offenses were more common among boys. Levels of oppositional behavior were greater at younger ages, aggression peaked near the middle of this age range, and property and status offenses were more prevalent at older ages. These findings are generally consistent with developmental models of conduct problems but are inconsistent with a recent model of gender differences and raise questions about the external validity of current taxonomies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Do peer-reviewed journal papers result from meeting abstracts of the Biennial Conference on the Biology of Marine Mammals?

Peer-reviewed publication is at the core of scientific communication. However, with the exception of biomedicine, there has been little analysis of the rate of peer-reviewed publication resulting from conference abstracts. This study examined a random sample of abstracts from the 1989 and 1991 Biennial Conferences on the Biology of Marine Mammals to determine how many were published as peer-reviewed papers. Publication rates were 51.4% (±4.7%) and 51.2% (±4.6%), respectively. This low abstract-to-publication rate, coupled with editorial policies prohibiting citation of conference abstracts in some journals, limits access to recent research, and thus affects the vibrance of the discipline.     

Aluminum-Lithium Alloy 1441 as a Promising Material for Fuselage

A comprehensive study of the suitability of sheets of alloy 1441 of the Al – Cu – Mg – Li system for the production of long-life airplane fuselages is described. The alloy has been used in the Be 103 boatplane airframe and is tested for use in the new business-class airplane of the A. N. Tupolev Aircraft Scientific-and-Engineering Company (ANTK). Sheets of alloy 1441 including thin ones with a thickness of 0.5 mm are manufactured by cold coil rolling. As compared to traditional deformable alloys of the Al – Cu – Mg system, alloy 1441 has a diminished density and an elevated modulus of elasticity at a comparable level of strength. Researchers in Russia (GP GNTs VIAM) and in the USA (LaRC, NASA) studied the tensile mechanical properties, the fracture toughness, the impact toughness, the fatigue resistance, and the growth rate of fatigue crack in sheets fabricated from alloy 1441. Researchers of the A. N. Tupolev ANTK fabricated fuselage panels with sheathing from alloy 1441 and stringers from high-strength aluminum alloy V95. The panels were tested in the ANTK and in the LaRC by the method of internal pressure by pulse-cycle simulation of the surface conditions of the airplane.