The relationship of shell dimensions and shell volume to live weight and soft tissue weight in the mangrove clam, Polymesoda erosa (Solander, 1786) from northern Australia

Shell dimensions (length, height, width) and shell volume were evaluated as estimators of growth for Polymesoda erosa in northern Australia. Each parameter was a good estimator when applied to live weight (r2 values of 76-96 percent), but not to soft tissue weight (wet, dry, or ash-free dry weight) (r2 values of 13-32 percent). The b value for shell volume to weight relationship of clams collected during the dry season (June to October) was signifi cantly different than for those collected in the wet season (February to April).

Analytical examination of animal remains from Borneo:the painting of bone and shell

Examination of a selection of shell and bone from archaeological assemblages excavated at Niah Cave and Gua Sireh, both of which are located in Sarawak, Borneo, has revealed the deliberate application of coloured material to one or more surfaces. Small fragments of the surface colourant were analysed using a variety of techniques, including microscopy, energy dispersive microwave analysis and infra-red spectrophotometry. These procedures established that, although red in colour, the applied coating in each instance was not red iron oxide. It is suggested that, based on the chemical components present, this coating was a tree resin or a similar organic substance. The paper further reports the presence of enhanced chloride values in the colourant recovered from the ancient human cranial fragment tested. It is suggested that elevated concentrations of this trace element may indicate that the site, the human remains or ingredients within the colourant were once in close proximity to the sea. (C) 2010 Elsevier Ltd. All rights reserved.

Rangia and Marsh Clams, Rangia cuneata, R. flexuosa, and Polymesoda caroliniana, in Eastern México: Distribution, Biology and Ecology, and Historical Fisheries

Rangia and marsh clams, Rangia cuneata, R. flexuosa, and Polymesoda caroliniana, occur in brackish waters along México’s eastern coast from the northern State of Tamaulipas to the southern State of Campeche. The clams were important to the prehispanic people in the southern part of the State of Veracruz, where they were used as food and as construction material. In modern times, they are harvested for food. The fishermen wade in shallow water and harvest the clams in soft sediments by hand. Annual landings of whole clams during a recent 5-yr period, 1998–2002, were 1,139–1,695 t. The only area with a substantial ongoing clam fishery is in the Lower Papaloapan River Basin, including Alvarado Lagoon, where as many as 450 fishermen are licensed harvesters. This fishery for the Rangia and marsh clams is the most important clam fishery along México’s Gulf Coast.

Producción de primicia en invernadero de híbridos de espárrago verde (Asparagus officinalis var. Altilis) en su cuarto año productivo

Resumen: La producción de espárragos en Argentina está caracterizada por una elevada estacionalidad concentrada en el periodo octubre-diciembre, por lo que el empleo de invernaderos brinda la posibilidad de ampliar el calendario de oferta, anticipando la entrada en producción. Con el objetivo de evaluar el rendimiento de primicia de diferentes híbridos de espárrago verde, se realizó un ensayo en invernadero con ocho híbridos, en UCA Buenos Aires, iniciado el 15/11/2006, mediante plantines de 100 días a 1m*0,3m. Se evaluaron los siguientes genotipos: Italo, Zeno, Eros, Ercole, H-668, Marte, y Giove, de origen italiano, y UC-157 de origen americano, como testigo por ser el tradicionalmente cultivado en Argentina. Se evaluaron 22 cosechas, con una frecuencia de día por medio, del 17/08/2011-25/10/2011. Se estudiaron diferencias en kg totales y comerciales (PFT y PFC), Nº turiones totales y comerciales/ha (NTT y NTC) y distribución de calibres (DC): Jumbo (J), Extra-Large (XL), Large (L), Medium (M), Small (S) y Asparagina (A). Se efectuó un análisis multifactor ANOVA LSD test (P>0.05). En promedio se obtuvieron: PFT: 17053; PFC: 7904 kg.ha-1; NTT: 670566 y NTC: 520938 turiones.ha-1. Se destacaron: en PFT: Italo: 29458a, Zeno: 23056b, Giove: 23034b y H-668: 18568bc; en PFC: Italo: 14850a, Giove: 9856b, Zeno: 9130bc y H-668: 8228bcd; en NTT: Italo: 842512a, H-668: 754512a, Giove: 715000b y Eros: 707498b; en NTC: Italo: 844998a, H-668: 667502b y Eros: 542498bc y en DC: en J: Italoa, Gioveb, Zenobc y UC-157bcd; en XL: Italoa, Zenoab y Gioveb; en L: Giovea, Italoa, Zenoab, H-668abc y UC-157abc; en M: Italoa, H-668ab y Erosab; en S: H-668a, Erosa e Italoab y en A: H-668a y Marteab. Por lo expuesto resulta alentadora la productividad de Italo, Giove, Zeno y H-668 para producción de espárrago verde de primicia en invernadero.

ROLE OF PHOSPHORUS CYCLING IN ALGAL METABOLISM AND ALGAL SUCCESSION IN LAKE DONGHU, CHINA

The role of phosphorus cycling in algal metabolism was studied in a shallow lake, Donghu, in Wuhan using the methods of measuring cell quota C, N and P, and calculating nutrients uptake rate by algal photosynthesis. The mean daily phosphorus uptake rate of phytoplankton varied between 0.04-0.11 and 0.027-0.053 g/m2/d in station I and station II respectively. The turnover time of phosphorus in phytoplankton metabolism ranged from 0.75-5.0 days during 1979-1986. The available P was 0.176 (+/- 0.156) g/m3 (mean +/- SD) in 1982 and 0.591 (+/- 0.24) g/m3 in 1986. The relationship between P/B ratio (Y) and TP (X: mg/l) was described by the following regression equation Y = 1.163 + 0.512logX (r = 0.731, P < 0.001). The dynamics of algal biomass and algal species succession were monitored as the indicators of environmental enrichment. The small-sized algae have replaced the blue-green algae as the dominant species during 1979-1986. The small-sized algae include Merismopedia glauca, Cryptomonas ovata, Cryptomonas erosa, several species Cyclotella. There has been drastic decrease in algal biomass and an obvious increase in P/B ratio. A nutrient competition hypothesis is proposed to explain the reason of the disappearance of blue-green algae bloom. The drastic change in algal size and the results in high P/B ratio (reaching a maximum mean daily ratio of 1.09 in 1986) may suggest a transition of algal species from K-selection to r-selection in Lake Donghu.

Antiviral activity of plants occurring in the state of minas gerais (Brazil): Part III

A total of 24 extracts from 14 plant species collected at the state of Minas Gerais, Brazil, and belonging to five botanical families (Annonaceae, Apocynaceae, Ochnaceae, Polygonaceae and Vitaceae) was screened for cytotoxicity in cultured Vero cells and for antiviral activity against human herpes virus type 1 (HSV-1), vaccinia virus (VACV) and murine encephalomyocarditis virus (EMCV). The highest cytotoxicity (CC 50 < 10 μg/mL) was observed for the ethanol extracts from Annona coriacea fruits and seeds. Extracts from Hancornia speciosa, Ouratea castaneafolia and O. semisrrata were the only ones that have shown activity against all the three viruses assayed. Extracts from Polygonum spectabile, Hancornia speciosa, Himatanthus phagedaenica, Ouratea spectabilis and O. semiserrata were the most active against HSV-1 (EC 50 < 50 mg/mL), with favorable SI values (8.0 to 10.0). Hancornia speciosa and Anaxagorea dolichocarpa were the most active against EMCV (EC 50 50 - 100 μg/mL), with reasonable SI values (5.2 to 6.1), while moderate to low activity (EC 50 > 100 μg/mL) was observed for Ouratea spectabilis and O. semiserrata. A total of 7 plant species, Ouratea semiserrata, O. spectabilis, O. castanaeafolia, Rollinia laurifolia, Cissus erosa, Polygonum spectabile, and Hancornia speciosa, were active against VACV, disclosing EC50 < 50 μg/mL and SI values ranging from 6.6 to 67.3. In total, 10 out of the 14 species were selected from a literature survey on plants used to treat viral diseases in Brazil; these species were responsible for 70% of the positive results.