Masses and Internal Structure of Mesons in the String Quark Model

The relativistic quantum string quark model, proposed earlier, is applied to all mesons, from pion to $\Upsilon$, lying on the leading Regge trajectories (i.e., to the lowest radial excitations in terms of the potential quark models). The model describes the meson mass spectrum, and comparison with measured meson masses allows one to determine the parameters of the model: current quark masses, universal string tension, and phenomenological constants describing nonstring short-range interaction. The meson Regge trajectories are in general nonlinear; practically linear are only trajectories for light-quark mesons with non-zero lowest spins. The model predicts masses of many new higher-spin mesons. A new $K^*(1^-)$ meson is predicted with mass 1910 Mev. In some cases the masses of new low-spin mesons are predicted by extrapolation of the phenomenological short-range parameters in the quark masses. In this way the model predicts the mass of $\eta_b(1S)(0^{-+})$ to be $9500\pm 30$ MeV, and the mass of $B_c(0^-)$ to be $6400\pm 30$ MeV (the potential model predictions are 100 Mev lower). The relativistic wave functions of the composite mesons allow one to calculate the energy and spin structure of mesons. The average quark-spin projections in polarized $\rho$-meson are twice as small as the nonrelativistic quark model predictions. The spin structure of $K^*$ reveals an 80% violation of the flavour SU(3). These results may be relevant to understanding the ``spin crises'' for nucleons.Comment: 30 pages, REVTEX, 6 table

Open data from the third observing run of LIGO, Virgo, KAGRA, and GEO

The global network of gravitational-wave observatories now includes five detectors, namely LIGO Hanford, LIGO Livingston, Virgo, KAGRA, and GEO 600. These detectors collected data during their third observing run, O3, composed of three phases: O3a starting in 2019 April and lasting six months, O3b starting in 2019 November and lasting five months, and O3GK starting in 2020 April and lasting two weeks. In this paper we describe these data and various other science products that can be freely accessed through the Gravitational Wave Open Science Center at https://gwosc.org. The main data set, consisting of the gravitational-wave strain time series that contains the astrophysical signals, is released together with supporting data useful for their analysis and documentation, tutorials, as well as analysis software packages

Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo

Despite the growing number of binary black hole coalescences confidently observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include the effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that have already been identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total source-frame mass M > 70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz emitted gravitational-wave frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place a conservative upper limit for the merger rate density of high-mass binaries with eccentricities 0 < e ≤ 0.3 at 16.9 Gpc−3 yr−1 at the 90% confidence level

Quantifying the impact of in-field rainwater harvesting (IRWH) production techniques on household food security for communal farmers in Thaba Nchu, Free State Province

The paper investigates the impact of employing in-field rainwater harvesting (IRWH) production techniques on household food security for communal farmers in Thaba Nchu, by estimating the minimum area of land that a representative household needs to cultivate in order to meet its requirements. First, using a poverty datum line for South Africa, annual income required by an average household for food and other basic necessities (shelter and clothes) is calculated, given a specific level of non-farm income for a typical household in the study area. Second, the caloric requirement for an average household's is estimated by using the daily caloric requirement of each member of the household. The household uses its income from non-farm sources to purchase food and where necessary supplemented with income from the sale of non-food agricultural production. In both cases minimum farm size is influenced by output levels and by profitability of crop production under IRWH techniques

Quantifying the impact of in-field rainwater harvesting (IRWH) production techniques on household food security for communal farmers in Thaba Nchu, Free State Province

The paper investigates the impact of employing in-field rainwater harvesting (IRWH) production techniques on household food security for communal farmers in Thaba Nchu, by estimating the minimum area of land that a representative household needs to cultivate in order to meet its requirements. First, using a poverty datum line for South Africa, annual income required by an average household for food and other basic necessities (shelter and clothes) is calculated, given a specific level of non-farm income for a typical household in the study area. Second, the caloric requirement for an average household's is estimated by using the daily caloric requirement of each member of the household. The household uses its income from non-farm sources to purchase food and where necessary supplemented with income from the sale of non-food agricultural production. In both cases minimum farm size is influenced by output levels and by profitability of crop production under IRWH techniques.Food Security and Poverty,

What do babies eat? Evaluation of a food frequency questionnaire to assess the diets of infants aged 6 months

OBJECTIVE: To evaluate the relative validity of a food frequency questionnaire (FFQ) for assessing nutrient intakes in 6-month-old infants.Design and settingThe FFQ was developed to assess the diets of infants born to women in the Southampton Women's Survey (SWS), a population-based survey of young women and their offspring. The energy and nutrient intakes obtained from an interviewer-administered FFQ were compared with those obtained from a 4-day weighed diary.Subjects and methodsA sub-sample of 50 infants aged 6 months from the SWS had their diets assessed by both methods. The FFQ recorded the frequencies and amounts of milks, baby foods, regular foods and drinks consumed by the infants over the previous seven days. The diaries recorded the weights of all foods and drinks consumed by the infants on four separate days within 15 days following FFQ completion. RESULTS: Spearman rank correlation coefficients for intakes of energy, macronutrients and 18 micronutrients, determined by the two methods, ranged from r = 0.39 to 0.86; adjustment for energy intake tended to increase the correlation coefficients, range ra = 0.55 to 0.89. Bland-Altman statistics showed that mean differences between methods were in the range of -12.5 % to +12.5 % except for vitamin B12 (-18.9 %).ConclusionAlthough there were differences in absolute energy and nutrient intakes between methods, Spearman rank correlation coefficients indicated reasonable agreement in the ranking of intakes. The interviewer-administered FFQ is a useful tool for assessing energy and nutrient intakes of healthy infants aged about 6 months

Diversidade de afídeos na cultura do algodoeiro no município de Campo Verde (MT) Aphids diversity on cotton field in Campo Verde, Mato Grosso State

O objetivo deste trabalho foi verificar a diversidade de afídeos (Hemiptera: Aphididae) na cultura do algodoeiro (Gossypium hirsutum L.) no município de Campo Verde (MT). Os afídeos foram amostrados diretamente nas plantas e através de armadilhas tipo Moericke. As amostragens foram realizadas a cada dois dias, até 60 dias após a germinação das plantas. A espécie Aphis gossypii Glover prevaleceu nas amostragens realizadas sobre as plantas. Formas aladas, de ocorrência acidental na cultura, tais como Aphis spiraecola Patch e Rhopalosiphum padi (Linnaeus) também foram observadas. Com as armadilhas tipo Moericke foram capturados 2280 afídeos alados, pertencentes a 13 espécies: R. padi (52,6% do total), A. spiraecola (26,4%), A. gossypii (8,9%), Rhopalosiphum maidis (Fitch) (5,3%), Geopemphigus floccosus (Moreira) (3,1%), Uroleucon ambrosiae (Thomas) (1,5%), Rhopalosiphum rufiabdominalis (Sasaki) (1,3%), Myzus persicae (Sulzer) (0,4%), Sipha flava (Forbes) (0,3%), Pentalonia nigronervosa Coquerel, Tetraneura nigriabdominalis (Sasaki), Lizerius melanocallis (Quednau) e Toxoptera citricidus (Kirkaldy) (0,1% cada uma). Nas amostragens diretamente sobre as plantas foram observados ápteros e alados de A. gossypii e alados de A. spiraecola e R. padi. Nas armadilhas tipo Moericke, as principais espécies capturadas foram R. padi, A. spiraecola, A. gossypii e R. maidis.<br>This work was carried out in Campo Verde, Mato Grosso State, Brasil, and its objective was to determine the occurrence of aphid species (Hemiptera: Aphididae) on cotton field (Gossypium hirsutum L.). The aphids were sampled both directly on plants and with Moericke's traps. The samplings were accomplished every other day during 60 days. Aphis gossypii Glover prevailed on cotton plants. Winged forms accidental as Aphis spiraecola Patch and Rhopalosiphum padi (Linnaeus) also occurred. In the water-pan traps 2280 winged aphids were trapped, which are from 13 species: R. padi (52.6% of total), A. spiraecola (26.4%), A. gossypii (8.9%), Rhopalosiphum maidis (Fitch) (5.3%), Geopemphigus floccosus (Moreira) (3.1%), Uroleucon ambrosiae (Thomas) (1.5%), Rhopalosiphum rufiabdominalis (Sasaki) (1.3%), Myzus persicae (Sulzer) (0.4%), Sipha flava (Forbes) (0.3%), Pentalonia nigronervosa Coquerel (0.1%), Tetraneura nigriabdominalis (Sasaki) (0.1%), Lizerius melanocallis (Quednau) (0.1%) and Toxoptera citricidus (Kirkaldy) (0.1%). In the direct samplings on cotton plants were present both wingless and winged forms of the A. gossypii and winged forms of the A. spiraecola and R. padi. In the Moericke's traps, the main captured species are R. padi, A. spiraecola, A. gossypii and R. maidis

Aspectos biológicos de Aphis gossypii Glover, 1877 (Hemiptera: Aphididae) em três cultivares de algodoeiro e em três espécies de plantas daninhas Biological aspects of Aphis gossypii Glover, 1877 (Hemiptera: Aphididae) on three cotton cultivars and on three weeds species

Este trabalho teve como objetivo estudar os aspectos biológicos de A. gossypii em três cultivares de algodoeiro e em três espécies de plantas daninhas. O experimento foi conduzido no Laboratório de Controle Biológico, sob condições controladas de temperatura (25 &plusmn; 1ºC), umidade relativa do ar (70 &plusmn; 10%) e fotofase (12 horas). Foram utilizados seis tratamentos, correspondendo às cultivares de algodoeiro CNPA ITA 90, Coodetec 402 e Deltaopal e espécies de plantas daninhas: guanxuma (Sida santaremnensis), malva-preta (Sidastrum micranthum) e trapoeraba (Commelina benghalensis). As unidades experimentais (25 repetições) consistiram de placas de Petri contendo ágar-água a 1% solidificado. Nestas placas, os ofídeos foram mantidos individualmente sobre discos foliares (3cm de diâmetro) de seus respectivos tratamentos. Os menores valores, em dias, para a fase ninfal foram obtidos em CNPA ITA 90 (4,39 &plusmn; 0,74), Deltaopal (4,45 &plusmn; 0,75), Coodetec 402 (4,47 &plusmn; 0,75) e trapoeraba (4,75 &plusmn; 0,80). O período reprodutivo e a longevidade dos adultos variaram de 8,21 &plusmn; 0,85 a 15,52 &plusmn; 0,93 e 11,09 &plusmn; 0,97 a 24,33 &plusmn; 1,59 dias, respectivamente, sobre guanxuma e Deltaopal. As cultivares de algodoeiro são mais favoráveis a A. gossypii que as plantas daninhas e na ausência de plantas de algodoeiro, as plantas daninhas guanxuma, trapoeraba e malva-preta são hospedeiros potenciais para manutenção da população de A. gossypii.<br>The objective of this work was to study the biological aspects of A. gossypii on three cotton cultivars and on three weed species. The experiment was carried out in the Laboratory of Biological Control, under controlled conditions of temperature (25 &plusmn; 1ºC), relative humidity (70 &plusmn; 10%) and photophase (12h). Treatments were: three cotton cultivars (CNPA ITA 90, Coodetec 402 and Deltaopal) and three weed species (Sida santaremnensis, Sidastrum micranthum and Commelina benghalensis). The experimental units (25 replicates) consisted of Petri dishes containing agar-water (1%) solidified. Aphids were kept individually on leaf discs (3cm diameter) of each respective treatments. The lowest number of days for nymphal phase was obtained on CNPA ITA 90 (4.39 &plusmn; 0.74), Deltaopal (4.45 &plusmn; 0.75), Coodetec 402 (4.47 &plusmn; 0.75) and C. benghalensis (4.75 &plusmn; 0.80). Reproductive period and adult longevity varied from 8.21 &plusmn; 0.85 to 15.52 &plusmn; 0.93 and from 11.09 &plusmn; 0.97 to 24.33 &plusmn; 1.59 days, respectively on S. santaremnensis and Deltaopal. Cotton cultivars are more favorable to A. gossypii than weeds and, in the absence of cotton plants, S. santaremnensis, S. micranthum and C. benghalensis are potential hosts