The composite-tendency Robert-Asselin-Williams (RAW) filter in semi-implicit integrations

Timediscretization in weatherandclimate modelsintroduces truncation errors that limit the accuracy of the simulations. Recent work has yielded a method for reducing the amplitude errors in leap-frog integrations from first-order to fifth-order.This improvement is achieved by replacing the Robert–Asselin filter with the Robert–Asselin–Williams (RAW) filter and using a linear combination of unfiltered and filtered states to compute the tendency term. The purpose of the present article is to apply the composite-tendency RAW-filtered leapfrog scheme to semi-implicit integrations. A theoretical analysis shows that the stability and accuracy are unaffected by the introduction of the implicitly treated mode. The scheme is tested in semi-implicit numerical integrations in both a simple nonlinear stiff system and a medium-complexity atmospheric general circulation model and yields substantial improvements in both cases. We conclude that the composite-tendency RAW-filtered leap-frog scheme is suitable for use in semi-implicit integrations.

Small wars and insurgencies in theory and practice, 1500-1850

In early modern times, warfare in Europe took on many diverse and overlapping forms. Our modern notions of ‘regular’ and ‘irregular’ warfare, of ‘major war’ and ‘small war’, have their roots in much greater diversity than such binary notions allow for. While insurgencies go back to time immemorial, they have become conceptually fused with ‘small wars’. This is a term first used to denote special operations, often carried out by military companies formed from special ethnic groups and then recruited into larger armies. In its Spanish form, guerrilla, the term ‘small war’ came to stand for an ideologically-motivated insurgency against the state authorities or occupying forces of another power. There is much overlap between the phenomena of irregular warfare in the sense of special operations alongside regular operations, and irregular warfare of insurgents against the regular forces of a state. This book demonstrates how long the two phenomena were in flux and fed on each other, from the raiding operations of the 16th century to the ‘small wars’ or special operations conducted by special units in the 19th century, which existed alongside and could merge with a popular insurgency. This book is based on a special issue of the journal Small Wars & Insurgencies.

Patterns of oocyte development in natural habitat and captive Salminus hilarii Valenciennes, 1850 (Teleostei: Characidae)

Fecundity and oocyte development in Salminus hilarii female brood stock were analyzed with the aim of investigating the impact of migration impediment on oogenesis. Histological analyses of the ovaries were performed in adult females caught in two different environments-the TietA(a) River (natural) and captivity-and the gonadossomatic index, oocyte diameter and fecundity determined. Five germ cell development stages (oogonium, perinucleolar, cortical alveoli, vitellogenic, ripe) and two other structures (postovulatory follicles and atretic oocytes) were observed in females caught in the river. Captive animals lacked the ripe oocytes and postovulatory follicles and had a relatively higher number of atretic oocytes. Females in captivity are known to produce larger oocytes, and they release fewer eggs in each spawn (absolute fecundity) when compared with animals that are able to migrate. Our results suggest that the TietA(a) River is undergoing alterations which are being reflected in the reproductive performance of S. hilarii, mainly due to the presence of atretic oocytes in females caught in the river. The lack of postovulatory follicles and ripe oocytes in captive animals reveals that migratory impediment negatively impacts final oocyte maturation. However, the stage of maturation reached is adequate for ovulation induction with hormone manipulation.

Aminoacetone, a putative endogenous source of methylglyoxal, causes oxidative stress and death to insulin-producing RINm5f cells

Aminoacetone (AA), triose phosphates, and acetone are putative endogenous sources of potentially cytotoxic and genotoxic methylglyoxal (MG), which has been reported to be augmented in the plasma of diabetic patients. In these patients, accumulation of MG derived from aminoacetone, a threonine and glycine catabolite, is inferred from the observed concomitant endothelial overexpression of circulating semicarbazide-sensitive amine oxidases. These copper-dependent enzymes catalyze the oxidation of primary amines, such as AA and methylamine, by molecular oxygen, to the corresponding aldehydes, NH4+ ion and H2O2. We recently reported that AA aerobic oxidation to MG also takes place immediately upon addition of catalytic amounts of copper and iron ions. Taking into account that (i) MG and H2O2 are reportedly cytotoxic to insulin-producing cell lineages such as RINm5f and that (ii) the metal-catalyzed oxidation of AA is propagated by O-2(center dot-) radical anion, we decided to investigate the possible pro-oxidant action of AA on these cells taken here as a reliable model system for pancreatic beta-cells. Indeed, we show that AA (0.10-5.0 mM) administration to RINm5f cultures induces cell death. Ferrous (50-300 mu M) and Fe3+ ion (100 mu M) addition to the cell cultures had no effect, whereas Cu2+ (5.0-100 mu M) significantly increased cell death. Supplementation of the AA- and Cu2+-containing culture medium with antioxidants, such as catalase (5.0 mu M), superoxide dismutase (SOD, 50 U/mL), and N-acetylcysteine (NAC, 5.0 mM) led to partial protection. mRNA expression of MnSOD, CuZnSOD, glutathione peroxidase, and glutathione reductase, but not of catalase, is higher in cells treated with AA (0.50-1.0 mM) plus Cu2+ ions (10-50 mu M) relative to control cultures. This may imply higher activity of antioxidant enzymes C, in RINm5f AA-treated cells. In addition, we have found that AA (0.50-1.0 mM) Plus Cu2+ (100 mu M) (i) increase RINm5f cytosolic calcium; (ii) promote DNA fragmentation; and (iii) increase the pro-apoptotic (Bax)/antiapoptotic (Bcl-2) ratio at the level of mRNA expression. In conclusion, although both normal and pathological concentrations of AA are probably much lower than those used here, it is tempting to propose that excess AA in diabetic patients may drive oxidative damage and eventually the death of pancreatic beta-cells.

Baptiströrelsen i Piteå : En studie av baptismens framväxt och utbildning mellan 1850 och 1910

Det övergripande syftet med denna uppsats har varit att undersöka baptismens framväxt, genombrott och utveckling under perioden 1850-1910. I anslutning till detta har jag även studerat baptismens etablering på nationell nivå. De frågeställningar som har utformats i anknytning till syftet har varit; När, varför och genom vilka uppkom baptismen i Piteå? Vilka människor kom att ansluta sig till baptismen i Piteå? Vilka orsaker fanns till baptismens förändring och utveckling på lokal nivå? Den metod som använts för att undersöka dessa aspekter har varit i huvudsak kvalitativ, där studiet av material i form av medlemsmatriklar, församlingsprotokoll, minnes- och årsskrifter samt relevant litteratur och avhandlingar använts. Resultatet av studien visar att den svenska baptiströrelsen har sin bakgrund i Amerika, England och Tyskland, och att den spreds till vårt land därifrån. En orsak till detta var gynnsamma samhällsförhållanden där läsar- och separatiströrelsen skapat en grogrund för baptisternas missionssträvanden under den första hälften av 1800-talet. I Piteå och Norrbotten etableras rörelsen i slutet av 1850-talet. Som förklaring till baptismens utveckling och förändring på lokal nivå har jag funnit att Piteå under perioden till övervägande del varit ett jordbrukssamhälle, vilket skapat en relativt låg grad av social rörlighet bland de unga anhängare som framför allt hämtades ur arbetarklassen. Utifrån tidigare studier av baptismen kan Piteå sägas vara ett exempel på ett samhälle där lojaliteten mot den äldre kyrkliga gemenskapen troligen levde kvar under perioden. Samtidigt hade församlingens idémässiga tankegods som folkrörelse en viktig social och ideologisk betydelse för individen, trots församlingens relativt små numerära framgångar.

Robert Cornell, Technical Editor, Electronic Technician Magazine

New York Trade School graduate Robert Cornell is pictured at his desk in his position of Technical Editor, Electronic Technician Magazine. Original caption reads "Robert Cornell - Advanced Television 1954, was appointed Technical Editor of Electronic Technician Magazine in 1956 and has served with distinction since. He is President of CETA (Certified Electronic Technicians Association), which consists of alumni of the New York Trade School who are graduates of the Advanced Television Course. He was recently invited to serve a a member of the Attorney General's Committee seeking to establish safeguards to protect the public in the field of television servicing." Black and white photograph with caption to glued to reverse.