Human hair growth deficiency is linked to a genetic defect in the phospholipase gene LIPH

The molecular mechanisms controlling human hair growth and scalp hair loss are poorly understood. By screening about 350,000 individuals in two populations from the Volga-Ural region of Russia, we identified a gene mutation in families who show an inherited form of hair loss and a hair growth defect. Affected individuals were homozygous for a deletion in the LIPH gene on chromosome 3q27, caused by short interspersed nuclear element-retrotransposon-mediated recombination. The LIPH gene is expressed in hair follicles and encodes a phospholipase called lipase H (alternatively known as membrane-associated phosphatidic acid-selective phospholipase A1alpha), an enzyme that regulates the production of bioactive lipids. These results suggest that lipase H participates in hair growth and development.     

Dipolar antiferromagnetism and quantum criticality in LiErF₄

Magnetism has been predicted to occur in systems in which dipolar interactions dominate exchange. We present neutron scattering, specific heat, and magnetic susceptibility data for LiErF(4), establishing it as a model dipolar-coupled antiferromagnet with planar spin-anisotropy and a quantum phase transition in applied field H(c|| = 4.0 ± 0.1 kilo-oersteds. We discovered non-mean-field critical scaling for the classical phase transition at the antiferromagnetic transition temperature that is consistent with the two-dimensional XY/h(4) universality class; in accord with this, the quantum phase transition at H(c) exhibits three-dimensional classical behavior. The effective dimensional reduction may be a consequence of the intrinsic frustrated nature of the dipolar interaction, which strengthens the role of fluctuations.     

The multielectron ionization dynamics underlying attosecond strong-field spectroscopies

Subcycle strong-field ionization (SFI) underlies many emerging spectroscopic probes of atomic or molecular attosecond electronic dynamics. Extending methods such as attosecond high harmonic generation spectroscopy to complex polyatomic molecules requires an understanding of multielectronic excitations, already hinted at by theoretical modeling of experiments on atoms, diatomics, and triatomics. Here, we present a direct method which, independent of theory, experimentally probes the participation of multiple electronic continua in the SFI dynamics of polyatomic molecules. We use saturated (n-butane) and unsaturated (1,3-butadiene) linear hydrocarbons to show how subcycle SFI of polyatomics can be directly resolved into its distinct electronic-continuum channels by above-threshold ionization photoelectron spectroscopy. Our approach makes use of photoelectron-photofragment coincidences, suiting broad classes of polyatomic molecules.     

Reports on establishing an ex situ site for ‘beautiful’ vavilovia (Vavilovia formosa) in Armenia

Vavilovia (Vavilovia Fed.) is one of the five genera in tribe Fabeae and consists of only one species, ‘beautiful’ vavilovia (Vavilovia formosa (Stev.) Fed.). The main centre of distribution is the Central and Eastern Caucasus, with a disjunct distribution among high alpine areas in the region, extending as far as West Turkey, Lebanon and Iran. In Armenia, in situ studies on Vavilovia started in the late 1930s. In July and August 2009, three expeditions were conducted to two locations: two to the Ughtasar Mountain and one to the Geghama Mountains. The first expedition to Ughtasar resulted in fresh plant collections and soil analysis for one of the sites. The expedition to Geghama established the existence of Vavilovia in the region of Lake Aknalitch. The second expedition to Ughtasar provided immature fruits and seeds. Collected plant material was transplanted into the Flora and Vegetation of Armenia plot of the Yerevan Botanic Garden established in 1940. Today, along with other plants the plot contains more than 200 species of wild relatives of cultural plants from 130 genera, including indiginous species of tribe Fabeae such as Vavilovia. The transplanted plants will continue to be monitored to see if the plants go on to successfully flower and set seed or whether further sites, possibly at higher altitudes might need to be tested to meet the long term conservation requirements of this iconic legume. These co-ordinated efforts provide a good example of an ex situ conservation strategy for Vavilovia formosa, which, if successful will improve access and utility for the whole legume research community.     

Biodegradation of humic substances by microscopic filamentous fungi: chromatographic and spectroscopic proxies

Purpose

The study of interactions between humic substances (HSs) and soil filamentous fungi is the key to understanding the sustainable soil functioning. The present work aims to examine the decomposition of HSs by filamentous dark-pigmented fungus Alternaria alternatа under the laboratory conditions and to determine the effect of easily assimilable organic carbon on this process. Analyzing such polydisperse substances like HSs by a complex integrated methodology makes it possible to explore the data on their decomposition by microorganisms.

Materials and methods

To achieve the aforementioned goals, we used chromatographic and spectroscopic approaches: low-pressure size-exclusion and hydrophobic interaction chromatography accompanied by absorption and fluorescence spectroscopy. To determine the effect cometabolism conditions produced on HS decomposition, two types of carbon substrates were added to the nutrient media: easily assimilable organic carbon (standard 0.3% or reduced 0.03% sucrose content) and hardly assimilable organic carbon (HSs), as well as their combinations. Five HS samples of different organic matter origin have been inspected: potassium humates (HPs) and humic acids (HAs) from coal, peat, and lignosulfonate. Correlation matrix and principal component analysis (PCA) were calculated for comprehensive data analysis.

Results and discussion

Transformations of the investigated HSs under fungal cultivation lead to the increase in the low molecular weight fraction, rise of hydrophilic fraction, enlargement of absorbance ratio A₂₅₀/A₃₆₅, shortening of the emission wavelength of the humic-type fluorescence, and growth in the fluorescence quantum yield measured with excitation at 355 nm. A positive correlation was observed between the accumulation of fungal biomass and the degree of HS decomposition. PCA analysis confirms that the difference in the results of HS decomposition largely depends on the sucrose content and the nature of HSs. We divided all the HS samples into four groups according to the degree of HS decomposition: original HS solutions, HPs altered using fungal cultivation at 0.03% sucrose, HAs after fungal cultivation at 0.03% sucrose, and finally, HSs (both HPs and HAs) after fungal cultivation at 0.3% sucrose.

Conclusions

In the laboratory experiments, we showed that (1) the isolated HAs were more effectively degraded than the parent HPs, and this process was more pronounced at a reduced sucrose content, and (2) the decomposition of stable organic compounds (HSs) was activated by the easily assimilable carbon sources (especially 0.3% sucrose) being present. We assume that it is the easily assimilable organic carbon that most likely triggers the HS degradation working as the priming effect in natural environments.

     

Ecological evaluation of polymetallic soil quality: the applicability of culture-dependent methods of bacterial communities studying

Purpose

This work aimed to study the effect of long-term polymetallic contamination on the state and parameters of soil bacterial communities, including the abundance of different groups of culturable bacteria and the activity of nitrification.

Materials and methods

Monitoring plots were located in the dry lake and surrounding area, which had been formerly used for the discharge of industrial waste. The soils in the 16 plots were characterized by extremely high levels of heavy metal pollution. This study evaluated the main soil physicochemical properties by various methods, total metal contents by X-ray analysis, mobile metal content by atomic absorption spectrophotometry, the abundance of chosen groups of culturable bacteria by inoculation on solid media, and nitrification activity from ammonium and nitrite oxidation rates.

Results and discussion

High adaptation capacity of microbial communities to long-term pollution was revealed through marked lack of decrease in the abundance of some of the bacterial groups in soils with high contamination levels. Among the bacteria determined by the colony count method, copiotrophic and spore-forming bacteria were the least sensitive to contamination, and actinomycetes were the most sensitive. The high levels of soil pollution with heavy metals had pronounced adverse effects on nitrification activity. The decrease in activity was strongly correlated with pollutant concentrations. The oxidation of nitrite was shown to be more affected by pollution that the oxidation of ammonium.

Conclusions

Some groups and parameters of culturable microorganisms can be used for soil status estimation under pollution conditions even though they are only a small fraction of the microbial community. The most sensitive parameter was the nitrification rate, while the number of actinomycetes was found to be most promising parameter among the groups of bacteria determined by plate counts. The use of sensitive groups of culturable microorganisms for bioindication purposes is a method, which may provide a cheap and sufficiently reliable tool for large-scale soil monitoring studies.

     

Effect of nanoparticles on crops and soil microbial communities

Purpose

Nanoparticles (NPs) have received increased attention in recent past due to their unique distinct properties. Metal-based NPs are widely used in chemical and allied sector. Most of the research is directed to study the efficiency of NPs in medicine and agriculture. The aim of this review is to explore the possible threats posed by toxicity of various NPs on plants and microbial diversity.

Materials and methods

First, major sources of NPs to the environment were analyzed. The effects of metal-based NPs on the microbiota and plants are presented in this review. The results obtained by the authors during last 12 years of research are used.

Results and discussion

The exposure of soil to nanoparticles causes a decrease in soil microbial biomass and enzymatic activity, which impacts microbial community composition including yeasts, bacteria, fungi, and biological diversity. The effects of NPs on plants result in various types of abnormalities. Nanoparticles can also pose risks to human health.

Conclusions

Increased applications of NPs pose a threat to beneficial microbial communities as well as crops and soils. Thus, it is important to explore whether NPs could compromise crop yield, soil properties, soil organisms, and functional activities of soil.

     

Temporal changes of eroded soils depending on their agricultural use in the southern Cis-Ural region

Temporal changes of eroded soils in the southern Cis-Ural region (Republic of Bashkortostan) depending on their agricultural use during the period from 1975 to 2011 were studied. In the northern foreststeppe zone, the development of erosion processes was retarded upon the use of soil-saving management practices and grain-fallow-grass crop rotations. In slightly eroded light gray forest soils (Eutric Retisols (Cutanic)), the thickness of humus-accumulative horizons and the content of humus increased; the conversion of cropland into permanent fallow was found to be the most efficient measure to control soil erosion. In podzolized chernozems (Luvic Greyzemic Chernic Phaeozems) and typical chernozems (Haplic Chernozems) of the Cis-Ural steppe, the content of humus in the plow layer under grain-row crop rotation and classical soil management decreased, especially in moderately eroded soils. The development of water and wind erosion on slopes depended on the slope shape: the texture of soils at different degrees of erosion on slopes with free runoff became coarser by one gradation after 35 years; in the presence of linear obstacles in the lower part of slopes, the content of fine fractions in moderately and strongly eroded soils increased.