SciCombinator

Discover the most talked about and latest scientific content & concepts.

87

Sex-specific elaborations are common in animals and have attracted the attention of many biologists, including Darwin [1]. It is accepted that sexual selection promotes the evolution of sex-specific elaborations. Due to the faster replenishment rate of gametes, males generally have higher potential reproductive and optimal mating rates than females. Therefore, sexual selection acts strongly on males [2], leading to the rapid evolution and diversification of male genitalia [3]. Male genitalia are sometimes used as devices for coercive holding of females as a result of sexual conflict over mating [4, 5]. In contrast, female genitalia are usually simple. Here we report the reversal of intromittent organs in the insect genus Neotrogla (Psocodea: Prionoglarididae) from Brazilian caves. Females have a highly elaborate, penis-like structure, the gynosome, while males lack an intromittent organ. The gynosome has species-specific elaborations, such as numerous spines that fit species-specific pouches in the simple male genital chamber. During prolonged copulation (∼40-70 hr), a large and potentially nutritious ejaculate is transferred from the male via the gynosome. The correlated genital evolution in Neotrogla is probably driven by reversed sexual selection with females competing for seminal gifts. Nothing similar is known among sex-role reversed animals.

Concepts: Sexual intercourse, Male, Reproduction, Female, Sex, Reproductive system, Gamete, Penis

39

To determine the relationship between the reduction in salt intake that occurred in England, and blood pressure (BP), as well as mortality from stroke and ischaemic heart disease (IHD).

Concepts: Blood, Myocardial infarction, Hypertension, Heart, Stroke, Heart disease, Artery, Ischemia

27

Brain-machine interfaces are not only promising for neurological applications, but also powerful for investigating neuronal ensemble dynamics during learning. We trained mice to operantly control an auditory cursor using spike-related calcium signals recorded with two-photon imaging in motor and somatosensory cortex. Mice rapidly learned to modulate activity in layer 2/3 neurons, evident both across and within sessions. Learning was accompanied by modifications of firing correlations in spatially localized networks at fine scales.

Concepts: Neuron, Spinal cord, Brain, Cerebral cortex, Skill, Cerebellum, Pyramidal cell, Calcium in biology

26

Novel high-throughput genetic techniques have increased the pace of discoveries in the field of primary aldosteronism. Mutations in the potassium channel gene KCNJ5 are a cause of familial and sporadic forms of primary aldosteronism with around 30-40% of aldosterone-producing adenomas being affected by somatic mutations.

Concepts: DNA, Gene, Genetics, Mutation, Evolution, Biology

26

Both aripiprazole and haloperidol have been used in the treatment of schizophrenia, and are metabolized by the cytochrome P450 (CYP) 2D6 and CYP3A4. The authors studied the correlations between the steady-state plasma concentrations (Css) of aripiprazole and its active metabolite, dehydroaripiprazole, and those of haloperidol in 19 Japanese patients with schizophrenia, together with the effects of CYP2D6 genotypes on the steady-state kinetics of these compounds.

Concepts: Cytochrome P450

26

To report a case of seizure-like symptoms in an infant exposed to bupropion and escitalopram through breastfeeding.

Concepts: Breastfeeding, Lactation

26

Extracorporeal life support for acute respiratory failure has increased as a result of technological advancements and promising results from recent studies as compared to historical trials.

Concepts: Intensive care medicine, Extracorporeal membrane oxygenation, Prehistory

26

Ni supported on silica-alumina is an efficient and reusable photocatalyst for the reduction of CO2 by H2 to methane reaching selectivity above 95 % at CO2 conversions over 90 %. Although NiO behaves similarly, it undergoes a gradual deactivation upon reuse. The photocatalytic activity of Ni/silica-alumina under solar light derives in about 26 % from the visible light photoresponse.

Concepts: Carbon dioxide, Energy, Light, Carbon, Carbon monoxide, Titanium dioxide, Photocatalysis, Visible spectrum

26

Nanoscale photocatalysts have attracted much attention due to their high surface area to volume ratios. However, due to extremely high reactivity, TiO2 and ZnO nanoparticles prepared using different methods tend to either react with surrounding media or agglomerate, resulting in the formation of much larger flocs and significant loss in reactivity. This work investigates the photocatalytic degradation of carbamazepine (CBZ), a persistent pharmaceutical compound from wastewater (WW) using TiO2 and ZnO nanoparticles prepared in the presence of a water-soluble whey powder as stabilizer. The TiO2 and ZnO nanoparticles prepared in the presence of whey stabilizer displayed much less agglomeration and greater degradation power than those prepared without a stabilizer. Higher photocatalytic degradation of carbamazepine was observed (100%) by using whey stabilized TiO2 nanoparticles with 55min irradiation time as compared to ZnO nanoparticles (92%). The higher degradation of CBZ in wastewater by using TiO2 nanoparticles as compared to ZnO nanoparticles was due to formation of higher photo-generated holes with high oxidizing power of TiO2. The photocatalytic capacity of ZnO anticipated as similar to that of TiO2 as it has the same band gap energy (3.2eV) as TiO2. However, in the case of ZnO, photocorrosion frequently occurs with the illumination of UV light and this phenomenon is considered as one of the main reasons for the decrease of ZnO photocatalytic activity in aqueous solutions. Further, the estrogenic activity of photocatalyzed WW sample with CBZ and its by-products was carried out by yeast estrogen screen (YES) assay method. Based upon the YES test results, none of the samples showed estrogenic activity.

Concepts: Ultraviolet, Estrogen, Quantum dot, Titanium dioxide, Zinc oxide, Photocatalysis, Sunscreen, Band gap

26

At monolayer coverage, silicene on Ag(1 1 1) may present different structural phases depending on the growth conditions. At multilayer coverage, only one structural phase has been reported: the [Formula: see text] phase. However, no link between the structural arrangement of the monolayer and that of the multilayer has been addressed. In this paper, reporting experimental work based on low-energy electron diffraction and scanning tunneling microscopy, we focus on the structural aspects of a multilayer film of silicene. We demonstrate that it exhibits one structural arrangement, namely the [Formula: see text] form, but with different domain orientations resulting from the structural properties of the initial wetting monolayer.

Concepts: Electron, Electron microscope, Diffraction, Microscopy, Scanning tunneling microscope, Scanning probe microscopy, Electron beam lithography, Low-energy electron diffraction