On the distribution of the signs of the conjugates of the cyclotomic units in the maximal real subfield of the qth cyclotomic field, q A prime

<p>Let F = ��(�� + ��^���1) be the maximal real subfield of the cyclotomic field ��(��) where �� is a primitive qth root of unity and q is an odd rational prime. The numbers u₁=-1, u_k=(��^k-��^-k)/(��-��^-1), k=2,���,p, p=(q-1)/2, are units in F and are called the cyclotomic units. In this thesis the sign distribution of the conjugates in F of the cyclotomic units is studied.</p> <p>Let G(F/��) denote the Galoi's group of F over ��, and let V denote the units in F. For each ���� G(F/��) and ����V define a mapping sgn_��: V���GF(2) by sgn_��(��) = 1 iff ��(��) �� 0 and sgn_��(��) = 0 iff ��(��) �� 0. Let {��₁, ... , ��_p} be a fixed ordering of G(F/��). The matrix M_q=(sgn_��j(v_i) ) , i, j = 1, ... , p is called the matrix of cyclotomic signatures. The rank of this matrix determines the sign distribution of the conjugates of the cyclotomic units. The matrix of cyclotomic signatures is associated with an ideal in the ring GF(2) [x] / (x^p+ 1) in such a way that the rank of the matrix equals the GF(2)-dimension of the ideal. It is shown that if p = (q-1)/ 2 is a prime and if 2 is a primitive root mod p, then M_q is non-singular. Also let p be arbitrary, let ��� be a primitive root mod q and let L = {i | 0 ��� i ��� p-1, the least positive residue of defined by ���ⁱ mod q is greater than p}. Let H_q(x) �� GF(2)[x] be defined by H_q(x) = g. c. d. ((�� xⁱ/I �� L) (x+1) + 1, x^p + 1). It is shown that the rank of M_q equals the difference p - degree H_q(x).</p> <p>Further results are obtained by using the reciprocity theorem of class field theory. The reciprocity maps for a certain abelian extension of F and for the infinite primes in F are associated with the signs of conjugates. The product formula for the reciprocity maps is used to associate the signs of conjugates with the reciprocity maps at the primes which lie above (2). The case when (2) is a prime in F is studied in detail. Let T denote the group of totally positive units in F. Let U be the group generated by the cyclotomic units. Assume that (2) is a prime in F and that p is odd. Let F₍₂₎ denote the completion of F at (2) and let V₍₂₎ denote the units in F₍₂₎. The following statements are shown to be equivalent. 1) The matrix of cyclotomic signatures is non-singular. 2) U���T = U². 3) U���F²₍₂₎ = U². 4) V₍₂₎/ V₍₂₎² = ��<i>v</i>₁ V₍₂₎²�� ���������<i>v</i>_p V₍₂₎²�� �� ��3V₍₂₎²��.</p> <p>The rank of M_q was computed for 5���q���929 and the results appear in tables. On the basis of these results and additional calculations the following conjecture is made: If q and p = (q -1)/ 2 are both primes, then M_q is non-singular. </p>

The rate and mechanism of the partial oxidation of acetaldehyde by PPM concentrations of nitrogen dioxide

<p>The thermal reaction between nitrogen dioxide and acetaldehyde in the gas phase was investigated at room temperature and atmospheric pressure. The initial rate of disappearance of nitrogen dioxide was 1.00 �� 0.03 order with respect to nitrogen dioxide and 1.00 �� 0.07 order with respect to acetaldehyde. An initial second order rate constant of (8.596 �� 0.189) x 10^-3 1.mole^-1 sec^-1 was obtained at 22.0 �� 0.1 ��C and a total pressure of one atmosphere. The activation energy of the reaction was 12,900 cal/mole in the temperature range between 22��C and 122��C. </p> <p>The products of the reaction were nitric oxide, carbon dioxide, methyl nitrite, nitromethane and a trace amount of trans-dimeric nitrosomethane. The addition of nitric oxide increased the rate of formation of nitromethane and decreased the rate of formation of methyl nitrite. There were no measurable surface effects due to the addition of glass wool or glass beads to the reactor.</p> <p>Reactants and products were analyzed by gas chromatography. A mechanism was proposed incorporating the principal features of the reaction.</p>

Natura eta ongizatea Bizkaian. Ekosistemen zerbitzuen ebaluazioa, ikerketa kudeaketan

Aurkibidea: - Hitzaurrea (Salvatore Aric��). - Aurkezpena (Miren Onaindia, Iosu Madariaga, Igone Palacios eta Xabier Arana). - Mezu gakoak. - Milurteko Ekosistemen Ebaluazioa Bizkaian proiektua: sarrera, helburuak eta kontzeptu orokorrak. - Zer zerbitzu ematen dizkigute Bizkaiko ekosistemek? - Nola banatzen dira lurraldean ekosistemen zerbitzuak? - Zer joera izan dute Bizkaiko ekosistemen zerbitzuek azken hamarkadetan? - Azterketa-kasuak: Bilboaldeko ingurune berdea, Urdaibai Biosfera Erreserba, Lea ibaiaren arroa eta Urkiolako Parke Naturala. - Murriztu daiteke lurraldeak kanpo-ekosistemen zerbitzuekiko duen mendekotasuna? - Nolakoa nahi genuke izatea Bizkaia 2050. urtean? - Zer erantzun-aukera ditugu eta zer erabaki har ditzakegu? - Bizkaiko ekosistemen zerbitzuen katalogoa. - Bizkaiko Ebaluazioarekin lotura duten argitalpenak. - Bizkaiko Ebaluazioarekin lotura duten webguneak. - Glosarioa.

Fibroblastos gengivais humanos em co-cultura com Aggregatibacter actinomycetemcomitans lisog��nico induzem a libera����o de fago

A rela����o entre bacteri��fagos e virul��ncia bacteriana �� um modelo muito intrigante e pouco estudado na patog��nese periodontal, uma vez que um pat��geno periodontal pode ser lisog��nico. O objetivo do nosso estudo �� determinar a capacidade de fibroblastos gengivais humanos de induzir as cepas lisog��nicas de Aggregatibacter actinomycetemcomitans. Dois experimentos foram realizados seguidos da titula����o de fago. Os experimentos consistiram da co-cultura com fibroblastos gengivais humanos e tr��s cepas de Aa [Aa29524, Aa2112, Aa29524(��2112)], n��o lisog��nica, lisog��nica e lisog��nica induzida em laborat��rio, respectivamente. Em tr��s momentos distintos (no experimento 1: 0, 2 e 4 horas; e no experimento 2: 2, 4 e 6 horas), o sobrenadante da co-cultura foi filtrado e cultivado overnight com a bact��ria indicadora (Aa29524) e analisado para a capacidade de lisar a c��lula indicadora. Em ambos os experimentos, o sobrenadante da co-cultura de fibroblastos gengivais humanos com Aa lisog��nico e Aa lisog��nico induzido em laborat��rio, ao ser cultivado com a bact��ria indicadora, promoveu lise da mesma, resultando no aumento da produ����o de fago. Pode-se concluir que, nesse estudo os fibroblastos gengivais humanos foram capazes de induzir cepas lisog��nicas de Aggregatibacter actinomycetemcomitans.

Estudio de optimizaci��n de la l��nea de evacuaci��n del parque e��lico de la S��a.

[ES]Estudio de la capacidad de transporte de energ��a del Parque e��lico de la S��a mediante la implementaci��n de un m��todo de c��lculo variable(CIGRE)en contraposici��n a los m��todos est��ticos y constantes. Mediante la comparaci��n y estudio de ��stos se evaluar�� la posibilidad de ampliar la capacidad del parque.

Proyecto de un parque e��lico para la alimentaci��n de las bombas de la central hidr��ulica de Belesar (Lugo).

[ES]El proyecto consiste en el estudio de las necesidades energ��ticas de las bombas de una central hidr��ulica y la construcci��n de un parque e��lico para satisfacer dichas necesidades. Para ello ser�� necesario llevar a cabo un estudio del ��rea y as�� encontrar el lugar m��s adecuado para ubicar los aerogeneradores, teniendo en cuenta la frecuencia, velocidad y direcci��n de los vientos predominantes del lugar. Despu��s habr�� que estudiar el mercado y elegir el aerogenerador adecuado para las condiciones del lugar y del viento, atendiendo tambi��n a otras cuestiones de relevancia. Se estudiar��, adem��s, la posibilidad de inyectar un posible exceso de electricidad a la red general. Una vez hecho esto, habr�� que calcular el coste del proyecto.

BotCam: a baited camera system for nonextractive monitoring of bottomfish species

A stereo-video baited camera system (BotCam) has been developed as a fishery-independent tool to monitor and study deepwater fish species and their habitat. During testing, BotCam was deployed primarily in water depths between 100 and 300 m for an assessment of its use in monitoring and studying Hawaiian bottomfish species. Details of the video analyses and data from the pilot study with BotCam in Hawai`i are presented. Multibeam bathymetry and backscatter data were used to delineate bottomfish habitat strata, and a stratified random sampling design was used for BotCam deployment locations. Video data were analyzed to assess relative fish abundance and to measure f ish size composition. Results corroborate published depth ranges and zones of the target species, as well as their habitat preferences. The results indicate that BotCam is a promising tool for monitoring and studying demersal fish populations associated with deepwater habitats to a depth of 300 m, at mesohabitat scales. BotCam is a flexible, nonextractive, and economical means to better understand deepwater ecosystems and improve science-based ecosystem approaches to management.

Reflex impairment as a measure of vitality and survival potential of Atlantic cod (Gadus morhua)

A ssur ing the v itality and survival potential of live-caught Atlantic cod (Gadus morhua) is important for improving the sorting of fish before net penning operations designed to hold fish for growth and later market. When Atlantic cod are captured by Danish seine, the most commonly used fishing gear for live-caught fish, they undergo stressors such as forced swimming, net abrasion, and air exposure. Laboratory experiments (at an air temperature of 9��C and water temperature of 8��C) were conducted with the aim of constructing a RAMP (reflex action mortality predictor) curve for prediction of vitality and survival potential in Atlantic cod captured in Danish seines, by varying the levels of these stressors. Atlantic cod exposed to increased duration in air (5���20 min) showed increased reflex impairment and mortality, with 75% mortality at 10 minutes of air exposure. Forced swimming in combination with net abrasion and air exposure did not increase reflex impairment or mortality above that associated with air exposure alone. The Atlantic cod RAMP curves indicated that fish with reflex impairment less than 50% would not show mortality and would likely recover from capture stress.

An assessment of discard mortality for two Alaskan crab species, Tanner crab (Chionoecetes bairdi) and snow crab (C. opilio), based on reflex impairment

Delayed mortality associated with discarded crabs and fishes has ordinarily been observed through tag and recovery studies or during prolonged holding in deck tanks, and there is need for a more efficient assessment method. Chionoecetes bairdi (Tanner crab) and C. opilio (snow crab) collected with bottom trawls in Bering Sea waters off Alaska were evaluated for reflexes and injuries and held onboard to track mortality. Presence or absence of six reflex actions was determined and combined to calculate a reflex impairment index for each species. Logistic regression revealed that reflex impairment provided an excellent predictor of delayed mortality in C. opilio (91% correct predictions). For C. bairdi, reflex impairment, along with injury score, resulted in 82.7% correct predictions of mortality, and reflex impairment alone resulted in 79.5% correct predictions. The relationships between reflex impairment score and mortality were independent of crab gender, size, and shell condition, and predicted mortality in crabs with no obvious external damage. These relationships provide substantial improvement over earlier predictors of mortality and will help to increase the scope and replication of fishing and handling experiments. The general approach of using reflex actions to predict mortality should be equally valuable for a wide range of crustacean species.

Effects of rapid decompression and exposure to bright light on visual function in black rockfish (Sebastes melanops) and Pacific halibut (Hippoglossus stenolepis)

Demersal fishes hauled up from depth experience rapid decompression. In physoclists, this can cause overexpansion of the swim bladder and resultant injuries to multiple organs (barotrauma), including severe exophthalmia (���pop-eye���). Before release, fishes can also be subjected to asphyxia and exposure to direct sunlight. Little is known, however, about possible sensory deficits resulting from the events accompanying capture. To address this issue, electroretinography was used to measure the changes in retinal light sensitivity, flicker fusion frequency, and spectral sensitivity in black rockfish (Sebastes melanops) subjected to rapid decompression (from 4 atmospheres absolute [ATA] to 1 ATA) and Pacific halibut (Hippoglossus stenolepis) exposed to 15 minutes of simulated sunlight. Rapid decompression had no measurable influence on retinal function in black rockfish. In contrast, exposure to bright light significantly reduced retinal light sensitivity of Pacific halibut, predominately by affecting the photopigment which absorbs the green wavelengths of light (���520���580 nm) most strongly. This detriment is likely to have severe consequences for postrelease foraging success in green-wavelength-dominated coastal waters. The visual system of Pacific halibut has characteristics typical of species adapted to low light environments, and these characteristics may underlie their vulnerability to injury from exposure to bright light.

Re-estimation of small-scale fishery catches for U.S. flag-associated island areas in the western Pacific: the last 50 years

Nearshore fisheries in the tropical Pacific play an important role, both culturally and as a reliable source of food security, but often remain under-reported in statistics, leading to undervaluation of their importance to communities. We re-estimated nonpelagic catches for Guam and the Commonwealth of the Northern Mariana Islands (CNMI), and summarize previous work for American Samoa for 1950���2002. For all islands combined, catches declined by 77%, contrasting with increasing trends indicated by reported data. For individual island entities, re-estima-tion suggested declines of 86%, 54%, and 79% for Guam, CNMI, and American Samoa, respectively. Except for Guam, reported data primarily represented commercial catches, and hence under-represented contributions by subsistence and recreational fisheries. Guam���s consistent use of creel surveys for data collection resulted in the most reliable reported catches for any of the islands considered. Our re-estimation makes the scale of under-reporting of total catches evident, and provides valuable baselines of likely historic patterns in fisheries catches.