Extraordinary Sex Ratios: Cultural Effects on Ecological Consequences

We model sex-structured population dynamics to analyze pairwise competition between groups differing both genetically and culturally. A sex-ratio allele is expressed in the heterogametic sex only, so that assumptions of Fisher's analysis do not apply. Sex-ratio evolution drives cultural evolution of a group-associated trait governing mortality in the homogametic sex. The two-sex dynamics under resource limitation induces a strong Allee effect that depends on both sex ratio and cultural trait values. We describe the resulting threshold, separating extinction from positive growth, as a function of female and male densities. When initial conditions avoid extinction due to the Allee effect, different sex ratios cannot coexist; in our model, greater female allocation always invades and excludes a lesser allocation. But the culturally transmitted trait interacts with the sex ratio to determine the ecological consequences of successful invasion. The invading female allocation may permit population persistence at self-regulated equilibrium. For this case, the resident culture may be excluded, or may coexist with the invader culture. That is, a single sex-ratio allele in females and a cultural dimorphism in male mortality can persist; a low-mortality resident trait is maintained by father-to-son cultural transmission. Otherwise, the successfully invading female allocation excludes the resident allele and culture, and then drives the population to extinction via a shortage of males. Finally, we show that the results obtained under homogeneous mixing hold, with caveats, in a spatially explicit model with local mating and diffusive dispersal in both sexes.Comment: final version, reflecting changes in response to referees' comment

Probability of the emergence of helical precipitation patterns in the wake of reaction-diffusion fronts

Helical and helicoidal precipitation patterns emerging in the wake of reaction-diffusion fronts are studied. In our experiments, these chiral structures arise with well-defined probabilities P_H controlled by conditions such as e.g., the initial concentration of the reagents. We develop a model which describes the observed experimental trends. The results suggest that P_H is determined by a delicate interplay among the time and length scales related to the front and to the unstable precipitation modes and, furthermore, the noise amplitude also plays a quantifiable role.Comment: 7 pages, 5 composite figure

Dugotrajno praćenje kompleksnog pacijenta s običnom varijabilnom imunodeficijencijom – prikaz bolesnika

Common variable immunodeficiency (CVID) is a primary immune disorder that results from insufficient immunoglobulin (IG ) secretion. Hypogammaglobulinemia is currently treated with substitute IG s, however, the substantial variation of post-application IG levels, as well as the development of complex clinical manifestations in patients set up a significant challenge for their physicians. A 33-year-old male patient has been followed-up with the diagnosis of CVID. From early childhood, he presented with recurrent respiratory infections. In 2010, he was diagnosed with CVID. Treatment was started with substitute intravenous (IV) IG . During a 9-year follow-up in day care and stationary University Hospital Centre (UHC) departments, the patient experienced a total of 14 respiratory and 2 digestive system complications of the disease. Eventually, he developed a non-infectious pulmonary complication – granulomatous- lymphocytic interstitial lung disease (GLILD). In 2015, treatment was altered to accomplish satisfactory IG levels from IV to conventional subcutaneous (SC) IG therapy. Due to easier application and greater volume of subcutaneously inserted IG , the patient was switched to a new generation of SCIG therapy in 2019. Additionally, corticosteroids and mesalazine were also administered, and with current treatment the patient is stable. In the 9-year period, he never reached the preferable reference levels of IG s presumed for healthy individuals. Respiratory infections are common CVID complications, but it is necessary to consider the autoimmune and neoplastic manifestations of the disease. A multidisciplinary approach, regular follow-up, and regular application of IG therapy are the key factors in decreasing morbidity and mortality in these patients.Obična varijabilna imunodeficijencija (CVID) oblik je primarne imunodeficijencije koja nastaje kao posljedicasmanjene proizvodnje imunoglobulina (IG ). Posljedična hipogamaglobulinemija trenutačno se liječi nadomještanjem IG -a, a značajne varijacije u postaplikacijskim vrijednostima IG -a kao i razvoj komplikacija osnovne bolesti predstavljaju značajan izazov u liječenju ovih pacijenata. Prikazujemo 33-godišnjeg muškarca koji se više godina prati s dijagnozom CVID-a. Od ranog djetinjstva pokazivao je podložnost opetovanim respiratornim infekcijama. Pacijentu je 2010. godine dijagnosticiran CVID te započinje liječenje intravenskim (IV) nadomjestkom IG -a. Tijekom devetogodišnjeg praćenja putem dnevne bolnice i stacionara Kliničkoga bolničkog centra pacijent je razvio ukupno 14 respiratornih i dvije probavne komplikacije osnovne bolesti. Razvio je i neinfektivnu plućnu komplikaciju: granulomatoznu limfocitnu intersticijsku plućnu bolest (GLILD). Bolesnik je 2015. godine sa svrhom postizanja poboljšanih vrijednosti IG -a prešao s IV na konvencionalnu supkutanu terapiju (SC) IG -a. Uslijed lakše primjene i povećanog volumena supkutanog unosa IG -a, 2019. godine dotadašnja terapija zamijenjena je novom generacijom SCIG pripravaka. Kao dodatak, propisani su mu kortikosteroidi i mesalazin te je pacijent s trenutačnom terapijom stabilno. U posljednjih devet godina nikada nije postigao referentne vrijednosti za zdrave osobe. Respiratorne infekcije česta su komplikacija CVIDa, ali je potrebno razmatrati i autoimune te neoplastične manifestacije ove bolesti. Multidisciplinarni pristup, redovito praćenje i redovita primjena imunoglobulina ključni su čimbenici u smanjenju morbiditeta i mortaliteta u pacijenata s CVID-om

Towards a perfect fixed point action for SU(3) gauge theory

We present an overview of the construction and testing of actions for SU(3) gauge theory which are approximate fixed points of renormalization group equations (at $\beta\rightarrow \infty$). Such actions are candidates for use in numerical simulations on coarse lattices.Comment: 6 pages, uuencoded compressed postscript file, contribution to LAT9

Observation of conduction electron spin resonance in boron doped diamond

We observe the electron spin resonance of conduction electrons in boron doped (6400 ppm) superconducting diamond (Tc =3.8 K). We clearly identify the benchmarks of conduction electron spin resonance (CESR): the nearly temperature independent ESR signal intensity and its magnitude which is in good agreement with that expected from the density of states through the Pauli spin-susceptibility. The temperature dependent CESR linewidth weakly increases with increasing temperature which can be understood in the framework of the Elliott-Yafet theory of spin-relaxation. An anomalous and yet unexplained relation is observed between the g-factor, CESR linewidth, and the resistivity using the empirical Elliott-Yafet relation.Comment: 10 pages, 11 figures, submitted to Phys. Rev.

Transport, Magnetic and Vibrational Properties of Chemically Exfoliated Few Layer Graphene

We study the vibrational, magnetic and transport properties of Few Layer Graphene (FLG) using Raman and electron spin resonance spectroscopy and microwave conductivity measurements. FLG samples were produced using wet chemical exfoliation with different post-processing, namely ultrasound treatment, shear mixing, and magnetic stirring. Raman spectroscopy shows a low intensity D mode which attests a high sample quality. The G mode is present at $1580$ cm$^{-1}$ as expected for graphene. The 2D mode consists of 2 components with varying intensities among the different samples. This is assigned to the presence of single and few layer graphene in the samples. ESR spectroscopy shows a main line in all types of materials with a width of about $1$ mT and and a $g$-factor in the range of $2.005-2.010$. Paramagnetic defect centers with a uniaxial $g$-factor anisotropy are identified, which shows that these are related to the local sp$^2$ bonds of the material. All kinds of investigated FLGs have a temperature dependent resistance which is compatible with a small gap semiconductor. The difference in resistance is related to the different grain size of the samples

The small molecule Mek1/2 inhibitor U0126 disrupts the chordamesoderm to notochord transition in zebrafish

<p>Abstract</p> <p>Background</p> <p>Key molecules involved in notochord differentiation and function have been identified through genetic analysis in zebrafish and mice, but MEK1 and 2 have so far not been implicated in this process due to early lethality (<it>Mek1-/-</it>) and functional redundancy (<it>Mek2-/-</it>) in the knockout animals.</p> <p>Results</p> <p>Here, we reveal a potential role for Mek1/2 during notochord development by using the small molecule Mek1/2 inhibitor U0126 which blocks phosphorylation of the Mek1/2 target gene Erk1/2 <it>in vivo</it>. Applying the inhibitor from early gastrulation until the 18-somite stage produces a specific and consistent phenotype with lack of dark pigmentation, shorter tail and an abnormal, undulated notochord. Using morphological analysis, in situ hybridization, immunhistochemistry, TUNEL staining and electron microscopy, we demonstrate that in treated embryos the chordamesoderm to notochord transition is disrupted and identify disorganization in the medial layer of the perinotochordal basement mebrane as the probable cause of the undulations and bulges in the notochord. We also examined and excluded FGF as the upstream signal during this process.</p> <p>Conclusion</p> <p>Using the small chemical U0126, we have established a novel link between MAPK-signaling and notochord differentiation. Our phenotypic analysis suggests a potential connection between the MAPK-pathway, the COPI-mediated intracellular transport and/or the copper-dependent posttranslational regulatory processes during notochord differentiation.</p