The Homothorax homeoprotein activates the nuclear localization of another homeoprotein, extradenticle, and suppresses eye development in Drosophila

The Extradenticle (Exd) protein in Drosophila acts as a cofactor to homeotic proteins. Its nuclear localization is regulated. We report the cloning of the Drosophila homothorax (hth) gene, a homolog of the mouse Meis1 proto-oncogene that has a homeobox related to that of exd. Comparison with Meis1 finds two regions of high homology: a novel MH domain and the homeodomain. In imaginal discs, hth expression coincides with nuclear Exd. hth and exd also have virtually identical, mutant clonal phenotypes in adults. These results suggest that hth and exd function in the same pathway. We show that hth acts upstream of exd and is required and sufficient for Exd protein nuclear localization. We also show that hth and exd are both negative regulators of eye development; their mutant clones caused ectopic eye formation. Targeted expression of hth, but not of exd, in the eye disc abolished eye development completely. We suggest that hth acts with exd to delimit the eye field and prevent inappropriate eye development.     

The Importance of Bonded Structural Material

Gluing is of tremendous importance to the wood industry. About 70% of all wood used today involves gluing. As an increasing amount of lower quality wood is used in the future, gluing will become even more important. Additional developments in harvesting previously unused species and forest residues and cleaning dirty material, and a means to reclaim urban waste wood, are needed to assure an adequate wood supply. New or improved economical adhesive systems will be important in accelerating the development of glued products. The future of the wood products industry lies with the use of glue, since the wood raw material will continue to be harvested in ever smaller sizes.     

Defining a strain‐induced time constant for oriented low shear‐induced structuring in high consistency MFC/NFC‐filler composite suspensions

Micro and nanofibrillated cellulose is an essentially one‐dimensional high aspect‐ratio particle material, which can undergo two‐dimensional layer (band) structuring under shear. Controlling the evolving rheological properties in aqueous suspension is essential for industrial applications in composite materials. This study focuses on an as yet considered to be unreported phenomenon of structure hardening under low shear. The timescale of the quasi gelation‐controlled structure formation under low shear is studied using the large gap vane‐in‐cup geometry of the Brookfield viscometer. It is proposed that localized structure forms within continuous shear bands, similar to quasi liquid‐crystal formation. By extrapolating a characteristic structure growth parameter to the rotation speed at which it becomes zero, the strain‐induced structure time constant, t_gel, can be obtained as (= f (Ω)) = 1/t_gel for the range Ω = 10–100/min. The time constant of low shear structure formation is shown to be separable from the static viscoelastic structure build under oscillation in concentrated composite suspension using plate‐plate geometry, which is manifest by a Weissenberg normal force response on switching to applied shear, when the time constant of structuration t_gel is long. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42827.     

Effect of ambulatory utilization review on referrals from generalists to specialists

We studied whether ambulatory utilization review (UR) alters how many patients internal medicine residents refer to sub-specialists, and whether the effect persists without reinforcement. We compared referral rates of residents from a firm that held UR meetings (intervention firm residents, n = 20) with those of residents from a firm that did not (control firm residents, n = 21). We then compared referral rates of 17 intervention firm residents while they were participating in UR with their rates after not participating for at least 4 weeks. Intervention firm residents submitted 30% fewer referrals than control firm residents (9% vs 13%, p = .05). However, the effect was short-lived; after 4 weeks without UR, intervention firm resident referral rates were similar to control firm referral rates.     

The min K channel underlies the cardiac potassium current IKs and mediates species-specific responses to protein kinase C

A clone encoding the guinea pig (gp) min K potassium channel was isolated and expressed in Xenopus oocytes. The currents, gpIsK, exhibit many of the electrophysiological and pharmacological properties characteristic of gpIKs, the slow component of the delayed rectifier potassium conductance in guinea pig cardiac myocytes. Depolarizing commands evoke outward potassium currents that activate slowly, with time constants on the order of seconds. The currents are blocked by the class III antiarrhythmic compound clofilium but not by the sotalol derivative E4031 or low concentrations of lanthanum. Like IKs in guinea pig myocytes, gpIsK is modulated by stimulation of protein kinase A and protein kinase C (PKC). In contrast to rat and mouse IsK, which are decreased upon stimulation of PKC, myocyte IK and gpIsK in oocytes are increased after PKC stimulation. Substitution of an asparagine residue at position 102 by serine (N102S), the residue found in the analogous position of the mouse and rat min K proteins, results in decreased gpIsK in response to PKC stimulation. These results support the hypothesis that the min K protein underlies the slow component of the delayed rectifier potassium current in ventricular myocytes and account for the species-specific responses to stimulation of PKC.     

Algal productivity in 49 lake waters as determined by algal assays

Algal assays were conducted on waters from 49 American lakes to determine whether phosphorus, nitrogen, or some other nutrient was the limiting factor upon algal productivity.A comparison of the known trophic state of 23 American lakes and their bioassay response is presented. Phosphorus limited algal growth in 35 of the 49 lakes assayed. Nitrogen was limiting in eight lakes and constituents other than nitrogen and phosphorus were limiting in six lakes. The results of this study indicated phosphorus limitation decreased as the productivity of the lake waters increased.     

Structural studies of EcoRII methylase: exploring similarities among methylases

EcoRII methyltransferase (M.EcoRII) is a cytosine-C5 DNA methylating enzyme. A model of its three-dimensional structure is proposed on the basis of homology modeling. Crystal structures of two members of the same family of enzymes, HaeIII and HhaI methyltransferases (M.HaeIII and M.HhaI respectively), were used as template molecules. Molecular dynamics was used to ensure sampling of conformationally stable structures. The final model has good geometry. The DNA and cofactor binding residues are in expected positions and form proper interactions. M.EcoRII is 147 amino acids longer than the template molecules, and hence the model contains several loops that are significantly longer than those in M.HaeIII and M.HhaI. The model provides a framework for interpretation and designing site-directed mutants that have a potential to improve crystallization experiments of this enzyme, and possibly other similar enzymes.      

Collaboration Structure, Communication Media, and Problems in Scientific Work Teams

This article reviews the structural characteristics of work organizations that are likely to increase collaboration problems and tests the relationships between collaboration structure and problems using data from a survey of scientists in four fields (experimental biology, mathematics, physics, and sociology). Two groups of problems are identified: problems of coordination and misunderstandings and problems of cultural differences and information security. Greater coordination problems are associated with size, distance, interdependence, and scientific competition. Problems of culture and security are associated with size, distance, scientific competition, and commercialization. Email use is associated with reporting fewer coordination problems, but not fewer problems of culture and security, while neither phone use nor face-to-face meetings significantly reduces problems. We conclude with a discussion of the implications of these findings for designers of collaboration technologies and researchers involved in scientific collaborations.