Modeling post-implantation stages of human development into early organogenesis with stem-cell-derived peri-gastruloids

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Functional response ofTelenomus reynoldsi [Hym.: Scelionidae] at five constant temperatures and in an artificial plant arena

The functional response ofTelenomus reynoldsi Gordh & Coker was determined at 5 constant temperatures using a dish arena. Functional response curves at all temperatures were of Holling's Type II. Handling rate increased linearly with increasing temperature, whereas the relationship of search rate to temperature was best described by a quadratic model. Search rate was highest at 32°C. Using Rogers' random parasite equation, analysis of the functional response in a more complex arena containing an artificial plant provided estimates of search and handling rates that may be more appropriate in the field environment. Search rate was 6,680 cm²/day. Handling rate was 13 hosts/day.      

Patterns and impacts of inorganic tripton in Cayuga Lake

Inorganic tripton in the upper waters of Cayuga Lake, NY, is characterized, quantified and contrasted for shallow (<6 m) and deep (>100 m) water regions based on analyses with scanning electron microscopy equipped with automated image analysis and X-ray energy spectroscopy (SAX) of samples collected in 1999 and 2000. The impacts of this material on water clarity and the phosphorus (P) pool are evaluated based on paired measurements of turbidity (T _n), Secchi disc transparency (SD), chlorophyll, and four fractions of particulate P (PP) determined according to selective extraction protocols. The major components of inorganic tripton in the lake are reported to be clay minerals and quartz, received from the watershed, and calcium carbonate (CaCO₃), that is produced internally. Clay minerals are the dominant component in a shallow region that receives tributary inflows. CaCO₃, precipitated during a mid-summer whiting event, is reported to be the dominant component of inorganic tripton for the deep water region for a low runoff year, while clays can become dominant in these areas after prolonged intervals of high runoff. It is demonstrated that inorganic tripton, rather than phytoplankton, is the primary regulator of T _n and SD, it represents most of the PP, and is primarily responsible for the higher T _n, lower SD, and higher TP in the shallow area compared to the deep water region. Efforts to improve clarity in this shallow region of the lake should consider the feasibility of controlling the input of terrigenous suspensoids rather than reductions in P loading.