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Timing the tides: Genetic control of diurnal and lunar emergence times is correlated in the marine midge Clunio marinus
Tobias S Kaiser, Dietrich Neumann, David G Heckel
BMC Genetics , 2011, DOI: 10.1186/1471-2156-12-49
Abstract: We crossed two strains of Clunio marinus that differ in the timing of the diurnal and lunar rhythms of emergence. The phenotype distribution of the segregating backcross progeny indicates polygenic control of the lunar emergence rhythm. Diurnal timing of emergence is also under genetic control, and is influenced by two unlinked genes with major effects. Furthermore, the lunar and diurnal timing of emergence is correlated in the backcross generation. We show that both the lunar emergence time and its correlation to the diurnal emergence time are adaptive for the species in its natural environment.The correlation implies that the unlinked genes affecting lunar timing and the two unlinked genes affecting diurnal timing could be the same, providing an unexpectedly close interaction of the two clocks. Alternatively, the genes could be genetically linked in a two-by-two fashion, suggesting that evolution has shaped the genetic architecture to stabilize adaptive combinations of lunar and diurnal emergence times by tightening linkage. Our results, the first on genetic control of lunar rhythms, offer a new perspective to explore their molecular clockwork.Lunar rhythms of reproduction are found in a number of species, especially from the intertidal zone [1-7], where the recurrent alternation between marine and terrestrial conditions results in huge fluctuations in abiotic factors. Certain tidal conditions re-occur predictably during the lunar cycle and the adaptive value of lunar rhythms can likely be attributed to restricting the delicate events of reproduction to suitable, narrow windows of time [7,8]. Lunar rhythms in reproduction are also reported for other marine species that do not experience tidal fluctuations, one of the most famous examples being the swarming of the Palolo Worm Eunice viridis in Samoa [9,10]. They are also reported for plankton and insects of tropical lakes [11,12]. In these cases the likely adaptive value of the lunar rhythm is to synchronize reprod
On a new neotropical species of the genus Djalmabatista Fittkau, 1968 (Diptera, Chironomidae)
Carraro, Vinicius Marins;Oliveira, Sebasti?o José de;Rego, Luis Eduardo Pereira do;
Memórias do Instituto Oswaldo Cruz , 1992, DOI: 10.1590/S0074-02761992000500011
Abstract: a new non-biting midge for the genus djalmabatista fittkau, 1968 (tanipodinae, chironomidae) from brazil is described.
Cytogenetics of a parthenogenetic Arctic species of Micropsectra (Diptera, Chironomidae)  [cached]
David Porter,Jon Martin
Comparative Cytogenetics , 2011, DOI: 10.3897/compcytogen.v5i4.1356
Abstract: Micropsectra sedna (Oliver, 1976) is a parthenogenetic midge from the Canadian Arctic. The parthenogenetic mechanism is apomictic thelytoky, with a restitutional division during oogenesis, as found in other parthenogenetic Chironomidae. It is triploid, with two similar chromosome sets, and the third is relatively dissimilar, pairing little with the diploid set. Two karyotypes were observed: a single individual with eight polytene elements in the salivary glands (3n=12), considered standard, while the majority of larvae showed only seven polytene chromosomes (3n=11). Hybrid speciation is considered likely, although chromosomal recombination following the origin of thelytoky has played some part in karyotype evolution. A single morphologically distinct larva was also found, which might be the donor of the haploid chromosome set. The apomictic restitutional system is compared to that of the other, independently derived, parthenogenetic Chironomids to assess the extent of similarity between species.
The Development of a Murine Model for Forcipomyia taiwana (Biting Midge) Allergy  [PDF]
Mey-Fann Lee, Kai-Jei Yang, Nancy M. Wang, Yung-Tsung Chiu, Pei-Chih Chen, Yi-Hsing Chen
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0091871
Abstract: Background Forcipomyia taiwana (biting midge) allergy is the most prevalent biting insect allergy in Taiwan. An animal model corresponding to the human immuno-pathologic features of midge allergy is needed for investigating the mechanisms and therapies. This study successfully developed a murine model of Forcipomyia taiwana allergy. Methods BALB/c mice were sensitized intra-peritoneally with midge extract on days 0, 7, 14, 21 then intra-dermally on days 28, 31 and 35. Serum midge-specific IgE, IgG1, and IgG2a were measured every 14 days by indirect ELISA. The mice were challenged intradermally with midge extract at day 40 and then sacrificed. Proliferation and cytokine production of splenocytes after stimulation with midge extract were determined by MTT assay and ELISA, respectively. The cytokine mRNA expression in response to midge stimulation was analyzed by RT-PCR. Results Serum IgE, total IgG, and IgG1 antibody levels against midge extract were significantly higher in the midge-sensitized mice than in the control mice. After the two-step sensitization, all mice in the midge-sensitized group displayed immediate itch and plasma extravasation reactions in response to challenge with midge extract. Skin histology from midge-sensitized mice showed marked eosinophil and lymphocyte infiltrations similar to that observed in humans. Stimulation of murine splenocytes with midge extract elicited significant proliferation, IL-4, IL-10, IL-13 and IFN-γ protein production, and up-regulation of mRNA in a dose-dependent manner in the midge-sensitized group, but not in the control group. Conclusions A murine model of midge bite allergy has been successfully developed using a two-step sensitization protocol. The sensitized mice have very similar clinical and immunologic reactions to challenge with midge proteins as the reactions of human to midge bites. This murine model may be a useful platform for future research and the development of treatment strategies for insect bite allergy.
Lunar eclipse induces disturbance in the lunar exosphere  [PDF]
Anil Raghav,Ankush Bhaskar,Virendra Yadav,Nitinkumar Bijewar,Chintamani Pai,Vaibhav Rawoot
Physics , 2014,
Abstract: Given the renewed scientific interest in lunar exploration missions, complete understanding of lunar near surface environment and its exosphere under different conditions is of paramount importance. Lunar exosphere has been extensively studied by ground based observations [18,19,20,21,22,23] and hypothesized by different models[1,2,3,4,5,6,7,8,9,10,11,12,13]. In present work, we have discussed overlooked possible sources behind changes in the lunar exosphere when the Moon passes through the penumbra and umbra of the Earth during a lunar eclipse. The dusty turbulent environment due to planetary shadow is not only confined to lunar studies and exploration, but it can also be extended to all terrestrial airless bodies in the universe with a dusty surface e.g. some planets, planetary satellites, asteroids etc.
Lunar Imaging and Ionospheric Calibration for the Lunar Cherenkov Technique  [PDF]
Rebecca McFadden,Olaf Scholten,Maaijke Mevius
Physics , 2013, DOI: 10.1063/1.4807516
Abstract: The Lunar Cherenkov technique is a promising method for UHE neutrino and cosmic ray detection which aims to detect nanosecond radio pulses produced during particle interactions in the Lunar regolith. For low frequency experiments, such as NuMoon, the frequency dependent dispersive effect of the ionosphere is an important experimental concern as it reduces the pulse amplitude and subsequent chances of detection. We are continuing to investigate a new method to calibrate the dispersive effect of the ionosphere on lunar Cherenkov pulses via Faraday rotation measurements of the Moon's polarised emission combined with geomagnetic field models. We also extend this work to include radio imaging of the Lunar surface, which provides information on the physical and chemical properties of the lunar surface that may affect experimental strategies for the lunar Cherenkov technique.
New phytotelmic habitat of Metriocnemus eryngiotelmatus (Diptera: Chironomidae)
Siri,Augusto; Donato,Mariano; Paggi,Analía C.;
Revista de la Sociedad Entomol?3gica Argentina , 2008,
Abstract: this is the first report of the non-biting midge metriocnemus eryngiotelmatus donato & paggi 2005 associated to the impounded water of dipsacus fullonum l. plants.
Lunar deflections of the vertical and their distribution  [PDF]
Jinyun Guo, Yu Sun, Xiaotao Chang, Fanlin Yang
Natural Science (NS) , 2011, DOI: 10.4236/ns.2011.35045
Abstract: The deflection of the vertical reflects the mass distribution and density anomaly of celestial bodies. Lunar deflections of the vertical include directional information of the Moon’s gravity field. SGM90d, recovered from SELENE mission, revealed the lunar far side gravity field for the first time in history owes to 4-way Doppler data. Lunar deflections of the vertical and their meridional and prime vertical components are calculated from SGM90d, and then their global distributions are also given in the paper. The gradients of lunar deflections of the vertical are defined and computed as well. The correlations between the lunar deflections of the vertical and the lunar terrain have been fully discussed. Many different characteristics of lunar deflections of vertical have been found between the near side and the far side of the Moon, which may be caused from the lithospheric compensation and the uplifting of mantle.
Aggregation behavior and rheology of culture broths of Rhodosorus marinus
Básaca-Loya, A;Burboa, M.G.;Valdez, M.A.;Gámez, R;Goycoolea, F.M.;Gutiérrez-Millán, L.E.;
Revista mexicana de física , 2008,
Abstract: we report the growth and rheological behavior of culture broths of the red microalga rhodosorus marinus, important as a source of phyco-biliproteins. the growing process of the culture broth was controlled with and without a carbon dioxide aeration process. by dynamic light scattering measurements, we investigate the cell-exopolysaccharide (eps) aggregation at different times of the culture broth and simultaneously, the hydrodynamic radius of the eps in the supernatant was measured. the results indicate that the cell-eps aggregation achieves a maximum at the stabilization stage of the culture time and at the end of the growing process, most of the cells remain disaggregated. measurements of apparent viscosity on both, culture medium and supernatant during the growing process showed a viscoelastic behavior and give a reasonable indication of the cell and eps maximum growth. the dry cell biomass and eps production of rhodosorus marinus resulted independent of the carbon dioxide aeration and were 5.7 g/l and 4.1 g/l, respectively. these are important results, compared with the ones obtained with similar microalgae.
Aggregation behavior and rheology of culture broths of Rhodosorus marinus
A. Básaca-Loya,M.G. Burboa,M.A. Valdez,R. Gámez
Revista mexicana de física , 2008,
Abstract: We report the growth and rheological behavior of culture broths of the red microalga Rhodosorus marinus, important as a source of phycobiliproteins. The growing process of the culture broth was controlled with and without a carbon dioxide aeration process. By dynamic light scattering measurements, we investigate the cell-exopolysaccharide (EPS) aggregation at different times of the culture broth and simultaneously, the hydrodynamic radius of the EPS in the supernatant was measured. The results indicate that the cell EPS aggregation achieves a maximum at the stabilization stage of the culture time and at the end of the growing process, most of the cells remain disaggregated. Measurements of apparent viscosity on both, culture medium and supernatant during the growing process showed a viscoelastic behavior and give a reasonable indication of the cell and EPS maximum growth. The dry cell biomass and EPS production of Rhodosorus marinus resulted independent of the carbon dioxide aeration and were 5.7 g/l and 4.1 g/l, respectively. These are important results, compared with the ones obtained with similar microalgae.
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