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Individual signaling pathways, such as fibroblast growth factors (FGFs), can regulate a plethora of inductive events. According to current paradigms, signal-dependent transcription factors (TFs), such as FGF/MapK-activated Ets family factors, partner with lineage-determining factors to achieve regulatory specificity. However, many aspects of this model have not been rigorously investigated. One key question relates to whether lineage-determining factors dictate lineage-specific responses to inductive signals or facilitate these responses in collaboration with other inputs. We utilize the chordate model Ciona robusta to investigate mechanisms generating lineage-specific induction. Previous studies in C. robusta have shown that cardiopharyngeal progenitor cells are specified through the combined activity of FGF-activated Ets1/2.b and an inferred ATTA-binding transcriptional cofactor. Here, we show that the homeobox TF Lhx3/4 serves as the lineage-determining TF that dictates cardiopharyngeal-specific transcription in response to pleiotropic FGF signaling. Targeted knockdown of Lhx3/4 leads to loss of cardiopharyngeal gene expression. Strikingly, ectopic expression of Lhx3/4 in a neuroectodermal lineage subject to FGF-dependent specification leads to ectopic cardiopharyngeal gene expression in this lineage. Furthermore, ectopic Lhx3/4 expression disrupts neural plate morphogenesis, generating aberrant cell behaviors associated with execution of incompatible morphogenetic programs. Based on these findings, we propose that combinatorial regulation by signal-dependent and lineage-determinant factors represents a generalizable, previously uncategorized regulatory subcircuit we term "cofactor-dependent induction." Integration of this subcircuit into theoretical models will facilitate accurate predictions regarding the impact of gene regulatory network rewiring on evolutionary diversification and disease ontogeny. [ABSTRACT FROM AUTHOR]

Abstract: Classical biological control programmes rely on mass production of high‐quality beneficial insects for subsequent releases into the field. Psyttalia lounsburyi (Silvestri) (Hymenoptera: Braconidae) is a koinobiont larval–pupal endoparasitoid of tephritid flies that is being reared to support a classical biological control programme for olive fruit fly in California. The mass‐rearing system for a P. lounsburyi colony, initiated with insects originally collected in Kenya, was evaluated with the goal of increasing production, while at the same time reducing time requirements for rearing in a quarantine facility. We tested the effect of exposure time of a factitious host Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), on parasitization, adult production, superparasitism, and sex ratio of P. lounsburyi and survival of the host. Parasitization rates were highest (31%) at 3‐ and 4‐hr exposure times, while adult production (i.e., emergence of wasp progeny) was highest (16%) at the 2‐hr exposure time. Superparasitism over the course of the study was 1.5% and did not appear to be a factor affecting parasitoid production. The sex ratio of wasp progeny was male‐biased and did not vary significantly over different exposure times. The rate of stings on host larvae increased with exposure time and was consistent with decreases in pupal eclosion from larvae and emergence rate of adult flies. When compared to current rearing procedures, the 2‐hr exposure time resulted in an overall 2.8‐fold increase in P. lounsburyi production when standardized for time. [ABSTRACT FROM AUTHOR]

Abstract: The >2.8 Ga siliciclastic-dominated, craton-cover succession with subordinate mafic volcanic rocks at Beniah Lake in the Slave craton has been informally referred to as the Bell Lake group. The Beniah Lake succession, up to 1 km thick, is composed of 7–120 m thick coarsening-upward (CU) sequences arranged with the following lithofacies architecture: (1a) argillite–sandstone, (1b) mafic volcanic lithofacies, (2) sandstone–argillite, (3a) quartz arenite and (3b) conglomerate lithofacies. A pan-Slave unconformity, indicating an autochthonous 2.8 to 4.013 Ga basement–cover relationship is present and locally well exposed. The lithofacies and their arrangement are consistent with a tide-influenced coastal setting, whereby the change from argillite–sandstone to quartz arenite lithofacies represents an initial estuary system, defining transgression with a maximum flooding surface, evolving into a fan-delta, defining progradation with a maximum regressive surface. The mafic volcaniclastic lithofacies and associated pillowed flow units, suggesting drowning of the siliciclastic succession, coincide with a change from rift to drift tectonics, as crustal attenuation facilitated magma ascent. The Slave-wide unconformities and lithofacies contacts permit a sequence stratigraphic approach, with the major Slave basement–quartz arenite unconformity suggestive of a 1st order sea level change coinciding with the proposed (super) continent break-up or rifting. The consistent stacking of CU-sequences with capping subaqueous volcaniclastic-volcanic units are considered the expression of 2nd order sea level cycles probably caused by changes of spreading rates at oceanic ridges. The CU-sequences and their thicknesses constitute 3rd order sea level changes and reflect the immediate response to crustal thinning. Time constraints for all these orders remain elusive but the hierarchy is consistent with sequence stratigraphic events. The observed relative sea level change is attributed primarily to tectono-eustasy where mantle dynamics caused rifting, basin subsidence and mafic volcanism. The latter occurred as the crust was sufficiently attenuated. [Copyright &y& Elsevier]

We examined the movement of aphelinid parasitoids from overwintering refuges into adjacent crops of cantaloupe and cotton. Eretmocerus eremicus and Encarsia spp. are important parasitoids attacking Bemisia tabaci Biotype B in the desert agricultural region of southeastern California. Movement was studied by marking naturally occurring field populations of parasitoids with rubidium chloride (RbCl). Two experimental study sites, each composed of natural enemy refuge strips and adjacent crops of cantaloupe and cotton, were grown for 2 years. Marking studies using RbCl demonstrated that the refuge strips supported early-season parasitoids which later migrated into adjacent crops. Between 15 - 63% of Eretmocerus eremicus caught in adjacent cotton and cantaloupe originated from the natural enemy refuges. Between 40 - 75% of aphelinids attacking B. tabaci in natural enemy refuges were Encarsia spp. while 98% of the marked, captured parasitoids in adjacent cotton and cantaloupe were Eretmocerus spp. Refuges produced higher numbers of whiteflies, relative to parasitoids, during spring months, showing the importance of refuge plants selective for natural enemies. This is the first known study using the marker RbCl that shows movement of naturally occurring Eretmocerus between an overwintering location and an adjacent crop. [ABSTRACT FROM AUTHOR]

Presents an obituary for Michael J. Rose, multifaceted pioneers of classical biological control in the U.S.

Increasing demand by the public and shareholders for substantial actions against the climate crisis is forcing organisations of all sectors to manage their greenhouse gas emissions more effectively. One method for organisations to reduce their emissions is Internal Carbon Pricing (ICP). So far, a comprehensive overview on ICP, especially on the impacts and barriers to its implementation, is missing. This paper closes the knowledge gap by summarising the motives for organisations to use ICP, by discussing the different ICP methods and by describing their impacts as well as identifying key implementation barriers. The work condenses the findings into a flow chart for easy identification of promising ICP methods while accounting for implementation barriers. The discussed ICP methods are emissions trading systems, proxy prices, carbon fees and hybrid systems. The review also discusses ICP methods which are not that common such as revenue-neutral carbon fees. The developed flow chart underlines two common barriers for implementing ICP. These are, 1) frequent difficulty allocating emissions to the responsible cost center within an organisation; 2) the challenge cost centers face reacting to the ICP by changing processes, technologies or products. Nevertheless, the results underline a variety of methods that allow the effective use of ICP under different organisation-specific circumstances. The literature review also emphasises the need for more in-depth case studies on the implementation of ICP within organisations. • Concise overview on the motivation, the methods, impacts and implementation barriers of internal carbon pricing. • Review of case studies where the impacts and problems of ICP are described. • Frequently used internal carbon pricing method is proxy prices. • First main implementation barrier is the ability to allocate emissions to the emission-responsible cost center. • Second main implementation barrier is the ability of cost centers to react to the ICP by changing processes or products. [ABSTRACT FROM AUTHOR]

A colony of the encyrtid wasp Psyllaephagus euphyllurae (Masi) (Hymenoptera, Encyrtidae) has been established in the quarantine laboratory at the University of California, Riverside, California, USA as part of a classical biological control program against its invasive host, the olive psylla, Euphyllura olivina (Costa) (Hemiptera, Psylloidea, Liviidae), an important pest of olives in some parts of the world. The colony originators were reared from the same host found on abandoned, commercial olives in Catalonia, Spain; additional collections were made in Murcia. The parasitoid reproduces primarily by thelytoky; however, a few occasional males have been found in the field in Spain, but not in colonies reared under quarantine or laboratory conditions. Here, the female of P. euphyllurae is redescribed and its male is described and illustrated for the first time; the only previous mention of male P. euphyllurae was from Tunisia, reared from the same psyllid host but without any details on its morphology. A lectotype is designated for Encyrtus euphyllurae Masi. Information is given on the results of genetic matching between the two sexes of the parasitoid and also on the presence of the bacterial Wolbachia symbiont that apparently is affecting reproduction of this species, including its sex ratio in the field. Two species of hyperparasitoids have also emerged from the parasitized olive psylla nymphs from Catalonia: numerous specimens of Apocharips trapezoidea (Hartig) (Hymenoptera, Figitidae) and one specimen of a Pachyneuron sp. (Hymenoptera, Pteromalidae). [ABSTRACT FROM AUTHOR]

The 20- to 1000-m-thick >2.8 Ga Bell Lake group is a siliciclastic-dominated succession in the Slave craton that contains features consistent with continental rifting. The Archean succession is composed of four principal lithofacies: (1) conglomerate, (2) quartz arenite, (3) sandstone-argillite, and (4) argillite-sandstone. An unconformity with 2.8-4.0 Ga basement indicates an autochthonous craton-cover relationship, and pillowed flows in depositional contact with the argillite-sandstone lithofacies reflect contemporaneous sedimentation and volcanism. The basement, composed of layered intrusions, granitic plutons, and gneissic rocks, served as the source for the quartz arenite with detrital chrornite. Mesoarchean Slave stratigraphic sections contain fining-upward (FU) and coarsening-upward (CU) sequences, with the former predominant at craton-cover contacts. The CU sequences are considered to be the results of rifting that produced a coastline featuring estuaries and embayments affected by tides and sporadic terrestrial floods. Successions from the Superior, Dharwar, and Zimbabwe cratons compare favorably with those of the Slave craton, wherein all examples contain quartz arenite, quartz pebble conglomerate, and basaltic-komatiitic volcanic rocks. The Slave craton, interpreted as a rifted continental margin, underwent significant crustal attenuation, which facilitated the ascent of mantle-derived magma. Modern analogues include a passive margin or shelf adjacent to an orogenic collision zone. The Bell Lake group and other documented craton-cover successions exhibit a recurring theme of early quartz-rich sedimentation and subsequent basaltic-komatiitic volcanism. This is consistent with continental breakup successions that are commonly induced by mantle plumes. [ABSTRACT FROM AUTHOR]

Presents a study which focuses on the stain-associated differences in hypoxic chemosensitivity in relation to the carotid body in rats. Information of the ventilatory responses; Anesthetizing of rats; Division of the images of whole carotid bodies.

We have developed 21 dinucleotide repeat microsatellite loci from African populations of Psyttalia lounsburyi (Silvestri) (Hymenoptera: Braconidae), a parasitoid wasp of the olive fruit fly, as part of a study assessing the role of introgression/hybridization in the success of a biological control introduction. We proposed suitable conditions for polymerase chain reaction multiplexing. All 21 loci were polymorphic with two to 21 alleles per locus within the Kenyan and South African populations tested. Most of them were successfully amplified in two other Psyttalia species. [ABSTRACT FROM AUTHOR]