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11.
12.
Piotr Sorokowski Agnieszka Sorokowska Dariusz P. Danel 《Economics & Human Biology》2013,11(3):382-390
Many studies have investigated how different variables influence the reproductive success (RS) in the populations of natural birth control. Here, we tested hypotheses about positive relationship between wealth, height and several measures of RS in an indigenous, traditional society from West Papua. The study was conducted among the Yali tribe in a few small, isolated mountain villages. In this tribe, a man's wealth is measured by the number of pigs he possesses. We found that wealth was related to fertility and number of living children, but not to child mortality in both men and women. Additionally, child mortality increased with the number of children in a family. Finally, we did not observe any relationship between height and reproductive success measures or wealth. We provide several possible explanations of our results and also put forward hypothetical background for further studies of indigenous populations. 相似文献
13.
Piotrowska Katarzyna Zgutka Katarzyna Kupnicka Patrycja Chlubek Dariusz Pawlik Andrzej Baranowska-Bosiacka Irena 《Biological trace element research》2020,194(1):177-183
Biological Trace Element Research - Intermitted fasting or every-other-day feeding (EOD) has many positive effects in rodents and humans. Our goal was to describe how EOD influences bone mineral... 相似文献
14.
Heavy metal-induced oxidative damage, defense reactions, and detoxification mechanisms in plants 总被引:7,自引:0,他引:7
Oksana Sytar Abhay Kumar Dariusz Latowski Paulina Kuczynska Kazimierz Strzałka M. N. V. Prasad 《Acta Physiologiae Plantarum》2013,35(4):985-999
Heavy metal (HMs) contamination is widespread globally due to anthropogenic, technogenic, and geogenic activities. The HMs exposure could lead to multiple toxic effects in plants by inducing reactive oxygen species (ROS), which inhibit most cellular processes at various levels of metabolism. ROS being highly unstable could play dual role (1) damaging cellular components and (2) act as an important secondary messenger for inducing plant defense system. Cells are equipped with enzymatic and non-enzymatic defense mechanisms to counteract this damage. Some are constitutive and others that are activated only when a stress-specific signal is perceived. Enzymatic scavengers of ROS include superoxide dismutase, catalase, glutathione reductase, and peroxidase, while non-enzymatic antioxidants are glutathione, ascorbic acid, α-tocopherol, flavonoids, anthocyanins, carotenoids, and organic acids. The intracellular and extracellular chelation mechanisms of HMs are associated with organic acids such as citric, malic and oxalic acid, etc. The important mechanism of detoxification includes metal complexation with glutathione, amino acids, synthesis of phytochelatins and sequestration into the vacuoles. Excessive stresses induce a cascade, MAPK (mitogen-activated protein kinase) pathway and synthesis of metal-detoxifying ligands. Metal detoxification through MAPK cascade and synthesis of metal-detoxifying ligands will be of considerable interest in the field of plant biotechnology. Further, the photoprotective roles of pigments of xanthophylls cycle under HMs stress were also discussed. 相似文献
15.
Ewa Rębacz-Maron Irena Baranowska-Bosiacka Izabela Gutowska Natalia Krzywania Dariusz Chlubek 《Biological trace element research》2013,156(1-3):91-95
The present study aimed at analysing the content of fluorine (F), calcium (Ca) and magnesium (Mg) in the hair of young male students (n?=?52) of a secondary school in Mafinga in Tanzania (Africa) who participated in anthropological examinations. Ca and Mg concentrations were determined using atomic absorption spectrophotometer while F levels using a potentiometric method. F in the hair of boys from older group (≥16 years old; n?=?24) was significantly higher than in the younger group (<16 years old; n?=?28) versus Ca and Mg levels. High carbohydrate diet was predominant—mainly based on corn or bean and meat served once a week, with few fruit and raw vegetables. Collective catering in the dormitory reflected habits and culinary preferences at home. The lack of balanced diet, with majority of the nutritional energy supplied by easily accessible and cheap carbohydrates, was reflected in dietary deficiencies, characterised, among others, by visible skin conditions and tooth decay. 相似文献
16.
Ewa Grzebelus Maria Kruk Alicja Macko-Podgórni Dariusz Grzebelus 《Plant Cell, Tissue and Organ Culture》2013,115(2):209-222
Protoplasts isolated from three accessions of cultivated carrot and 5-day-old protoplast-derived aggregates were subjected to selection to identify somaclonal variants with enhanced tolerance to the fungal disease black rot incited by Alternaria radicina. Different concentrations [1, 2, 3.5, 5, 10, 20, 35 and 50 % (v/v)] of a fungal culture filtrate (FCF) from 2-week-old liquid cultures of A. radicina were used. Protoplasts and aggregates were subjected to short-term selection for a period of 10 days. All FCF concentrations added to the cultures on the day of isolation decreased protoplast survival frequency and plating efficiency, while FCF applied 5 days later inhibited cell divisions in 5–50 % concentrations. The responses of protoplasts to the treatment were genotype dependent. Most R0 plants were regenerated in all accessions from cell lines grown with 1 % FCF, while only a few plants were produced from 2 to 3.5 % FCF-treated cultures of ‘Dolanka’ and the breeding line ‘9304B’, respectively. Nineteen-percent of putative stress-tolerant regenerants were tetraploids, while only 5 % tetraploids were observed in the control. The incidence of unique random amplified polymorphic DNA fragments indicating possible chromosomal rearrangements was low and did not differ among regenerants after selection and those derived from the control. Mobilization of miniature inverted repeat transposable elements was not observed. Some R0 individuals regenerated both from FCF-treated and untreated cultures showed lower susceptibility to A. radicina in a laboratory assay in comparison to control plants grown from seed. Regenerants from FCF-treated cultures showed lower frequency of flowering plants and a higher rate of male sterility. Pollen viability of the putative stress-tolerant regenerants varied over a wide range (6–98 %), independently of in vitro selection conditions. Our data suggest that A. radicina FCF may be feasible for the in vitro selection to generate plants with superior phenotypic performance against A. radicina. 相似文献
17.
Dariusz Pańka Dariusz PiesikMałgorzata Jeske Anna Baturo-Cieśniewska 《Journal of plant physiology》2013
Grasses very often form symbiotic associations with Neotyphodium/Epichloë endophytic fungi. These endophytes often allow the host grass to be protected from different pathogens. However, there is little known about the mechanisms of such endophyte influence on the host. Thus, the purpose of this research was to examine the effect of the N. lolii endophyte on the total production of phenolic compounds, VOCs emission and the resistance of three perennial ryegrass genotypes infected by pathogenic Fusarium poae. Analyses of total phenolics content were performed in control (not inoculated) and inoculated plants after 1, 2, 3, 4, 5, and 6 days (DAI) and for VOCs after 0, 3, 6 and 12 DAI. The presence of endophytes significantly reduced the disease index in two of the three genotypes relative to that in E−. Plants infected by N. lolii exhibited higher production of phenolics relative to the E− plants. The highest amounts of phenolics were observed on the second and sixth DAI. Genotype Nl22 showed the strongest effect of the endophyte on the production of phenolics, which increased by over 61%. Both the endophyte infected and non-infected plants emitted most abundantly two GLVs ((Z)-3-hexenal, (Z)-3-hexen-1-yl acetate), three terpenes (linalool, (Z)-ocimene, β-caryophyllene) and three shikimic acid pathway derivatives (benzyl acetate, indole, and methyl salicylate). The endophyte presence and the intervals of VOCs detection were a highly significant source of variation for all emitted volatiles (P < 0.001). The genotype of the perennial ryegrass significantly affected only the emission of methyl salicylate (P < 0.05) and β-caryophyllene (P < 0.05). Most of the VOCs ((Z)-3-hexen-1-yl acetate, (Z)-3-hexenal, linalool and methyl salicylate) reached their highest levels of emission on the sixth DAI, when averaged over genotypes and endophyte status. The results highlight the role of Neotyphodium spp. in the mediation of quadro-trophic interactions among plants, symbiotic endophytes, invertebrate herbivores and plant pathogenic fungi. Our results also confirm the fact that symbiotic plants can activate a defense reaction faster than non-symbiotic plants after a pathogen attack. Thus, N. lolii can be involved in the defense of perennial ryegrass against pathogens and potentially could be central to the host plants’ protection. 相似文献
18.
Capsule Herons responded to the lower abundance of a preferred fish by switching prey. Aims To investigate how Grey Herons respond to the decline in abundance of a preferred fish, the Round Goby Neogobius melanostomus. Methods Grey Herons Ardea cinerea breeding in the Gulf of Gdańsk area (Baltic Sea) were the study population. Regurgitated food and pellets were analysed. Biomass and abundance of fish was compared between 2000–02 (when the population of Round Goby was increasing) and 2008–09 (when the Round Goby population stabilized). Results The abundance and biomass of Round Goby preyed upon by herons decreased from between 95 and 99% in 2000–02 to between 38 and 56% in 2008–09. Energy-rich salmonids, not recorded in 2000–02, were an important diet component in 2008–09 (42% of biomass). Small-sized fish abundance was higher in 2008–09 (37%) than in 2000–02 (9%). Conclusions Grey Herons in 2008–09 adapted to the lower availability of Round Gobies by prey switching to other available fish – abundant but small-sized Three-spined Sticklebacks Gasterosteus aculeatus and less abundant but more profitable salmonids (easy to catch in the case of hatchery-reared, tagged individuals). Diet composition suggests that Grey Herons in 2008–09 exploited more diverse foraging areas (dry habitats, woods, garden ponds) than in 2000–02. 相似文献
19.
Katarzyna Ciach Marek Niedoszytko Anna Abacjew-Chmylko Izabela Pabin Przemyslaw Adamski Katarzyna Leszczynska Krzysztof Preis Hanna Olszewska Dariusz G. Wydra Rita Hansdorfer-Korzon 《PloS one》2016,11(1)
Objective
To present current guidelines regarding treatment of mastocytosis in pregnancy on the example of observed patients.Design
Case control national study.Setting
Polish Center of the European Competence Network on Mastocytosis (ECNM).Population or Sample
23 singleton spontaneous pregnancies in 17 women diagnosed with mastocytosis in years 1999–2014, before becoming pregnant.Methods
Prospective analysis outcomes of pregnancies and deliveries.Main Outcome Measures
Survey developed in cooperation with the Spanish Instituto de Estudios de Mastocitosis de Castilla-La Mancha (CLMast), Hospital Virgen del Valle, Toledo, Red Espańola de Mastocitosis (REMA), Spain.Results
All 23 pregnancies resulted from natural conception. Obstetrical complications recorded in the first trimester included spontaneous miscarriage (5 pregnancies). Four patients delivered preterm, including one delivery due to preeclampsia at 26 weeks which resulted with neonate death due to extreme prematurity. Five women delivered via cesarean: four due to obstetrical indications and one due to mastocytosis, during which no anesthesia related complications were recorded. Of patients delivering vaginally, two received extradural anesthesia, three required oxytocin infusion due to uterine hypotonia. No labor complications were recorded. In one woman with pregnancy-induced hypertension, early puerperium was complicated by the presence of persistent arterial hypertension. One neonate was born with the signs of cutaneous mastocytosis. Another neonate was diagnosed with Patau syndrome. Four women were treated for mastocytosis prior to conception and continued therapy after becoming pregnant. One patient was put on medications in the first trimester due to worsening of her symptoms. Pregnancy exerted only a slight effect on the intensity and frequency of mastocytosis-related symptoms observed. Worsening of the disease-related symptoms was documented in only four patients (23%). None of the patients showed the signs of anaphylaxis, either before becoming pregnant, or during pregnancy and puerperium.Conclusions
There is no contraindication to pregnancy when mastocystosis-related pathologies are under appropriate medical control. 相似文献20.
David P. Belesky Jonathan J. Halvorson Joyce M. Ruckle Dariusz P. Malinowski Domingo J. Mata‐Padrino 《The Annals of applied biology》2019,175(1):42-53
Pastures in the Appalachian region of the United States comprise a mix of grasses, legumes and forbs that tend to differ in productivity within and among years. A high degree of spatial variability in hill‐land pasture creates microsite conditions that influence botanical composition of pasture. The variation in sward composition presents logistical challenges to livestock producers who rely on a dependable supply of herbage mass and nutritive value to meet production goals. Our objective was to determine if forage communities sown for specific functions, for example, superior dry matter productivity, resource patch exploitation or targeted seasonal production, adapted to changing growing conditions within and among years. Productivity of communities differed among years reflecting the cumulative influences of time, ontogenetic and environmental variations. Maximum productivity was influenced by the specific forage community and less so by simple clipping and fertiliser management. Naturalised swards clipped to emulate hay management tended to have sustained herbage productivity but lower nutritive value when compared to sown communities. Rankings of dry matter productivity of communities were similar for each year where bioactive composition, high productivity and warm season tended to produce the most, and stoloniferous‐rhizomatous and naturalised pasture the least. Regardless of initial sward composition, effective number of species as an index of diversity increased when frequently clipped swards were not fertilised, and when infrequently clipped swards were fertilised. Dry matter production patterns were not influenced by the effective number of species in any forage community suggesting that key species sustained productivity with volunteer species making lesser contribution to total productivity. The species composition of forage plant communities appears to be more important than clipping or fertiliser management practices as a means to sustain forage productivity. 相似文献