Determining the responses of vegetation to natural processes and human impacts in north-eastern Poland during the last millennium: combined pollen,geochemical and historical data

Pollen, charcoal and geochemical investigations were carried out on annually laminated sediments of Lake ?abińskie (54°07′54.5″N; 21°59′01.1″E) and the results were combined with historical and climate data to better understand the mechanism behind plant cover transformations. A millennium-long record of environmental history at 6-years time resolution permitted an assessment of vegetation responses to past human impact and climate fluctuations. Our results show that the history of the region with repeated periods of warfare, epidemics, famine and crop failures is well reflected by environmental proxies. Before the Teutonic Order crusade (ad 1230–1283), agricultural activities of the Prussian tribes were conducted at a distance from the studied lake and caused slight disturbances of local forests. A stronger human impact was registered after ca ad 1460. We confirm that co-domination of pine forests with spruce and oak-hornbeam forests on drier habitats as well as the presence of birch and alder woods on wet surfaces near the lake lasted until ad 1610. We identified a transition period of 20 years between ad 1590 and 1610, when forest cover was significantly reduced and the area was partly transformed into open land used for farming activities. The comparison of our data with other pollen datasets from the region confirms significant spatio-temporal differences in the initiation of large-scale woodland clearings in the Great Masurian Lake District. A strong increase in local cultivation was noted after ad 1750 and became even stronger in the period ad 1810–1940. The last 60 years experienced a succession from arable fields and open grasslands to more tree-covered habitats overgrown by birch and alder.     

Understanding the human impact on Akita-sugi cedar (<Emphasis Type="Italic">Cryptomeria japonica</Emphasis>) forest in the late Holocene through pollen analysis of annually laminated sediments from Ichi-no-Megata,Akita, Japan

Akita-sugi (Cryptomeria japonica, Japanese cedar that is grown in Akita) forests are among the most important for commercially valuable timber in Japan. Historically, these forests have been severely exploited, although now some parts of them are conserved. It is important to know the detailed history of the forests in order to utilize them sustainably in the future. This study analyzes the pollen in an annually laminated lake sediment core from Ichi-no-Megata on the Oga peninsula, Akita, Japan, to understand the history of Akita-sugi cedar forests. An age-depth model was developed based on the results of an accelerator mass spectrometer dating of 13 plant macrofossils from the surface to 422 cm in depth, the Towada-a tephra and other well-known event layers. The dominant pollen taxa were Cryptomeria and Fagus crenata by ad 1000. The first increase of Cryptomeria was detected around 1700 bc. By the 1st century ad, Cryptomeria forest was established. At that time, Cryptomeria was mixed with deciduous trees, mainly F. crenata. The pollen analysis found evidence that the main loss of woodland occurred during the 11th century ad, when forest lands were cleared for agriculture. Substantial natural forests nevertheless remained until the 16th century, after which forest resources were exhausted. Conservation and plantation activities took place later, but human activity in response to severe famines prevented the recovery of the forests. After the famine periods, the remaining forests recovered to their previous condition, but after World War II, the natural forests shrank further and plantation forests without deciduous trees were established over large areas.     

Investigation of peat sediments from Daiyun Mountain in southeast China: late Holocene vegetation,climate and human impact

In this study, late Holocene vegetation, climate and human impacts were investigated using multiproxy data-pollen percentages, pollen accumulation rates (PAR), humification and loss-on-ignition (LOI)—measured from peat sediments from Daiyun Mountain, southeast China. A stratigraphic chronology was established on the basis of four radiocarbon dates. The 4,350 year sequence of vegetation history and climate change exhibits three distinctive stages: (1) 4,350–1,000 cal bp, during which the vegetation was dominated by evergreen forests mainly composed of broad-leaf trees, indicating a warm and wet climate; (2) 1,000–550 cal bp, during which the climate was thought to be cool and dry, based on a decrease in pollen percentages and the PARs of trees, shrubs and wetland herbs, and an increase in the pollen percentage and PAR of dry land herbs, as well as high overall LOI values; and (3) 550 cal bp to modern times, during which higher pollen percentages of dry land and wetland herbs, along with low pollen percentage and PAR of trees and shrubs, as well as low absorbance and LOI values, suggest relatively cooler but wetter climate conditions. In addition, major climatic events, such as the warm period from ad 670–960, the Medieval Warm Period (ad 1050–1520) and the Little Ice Age (ad 1580–1850), could be identified within the peat sediments in this study, with climatic conditions at these times being characteristically warm and wet, warm and dry, and cold and wet, respectively. Pollen signals indicate significant human impact since 1,000 cal bp, which may be linked to the development of the local porcelain industry and a rapid increase in the population in the study region.     

Landscape use and fruit cultivation in Petra (Jordan) from Early Nabataean to Byzantine times (2nd century <Emphasis Type="SmallCaps">bc</Emphasis>–5th century <Emphasis Type="SmallCaps">ad</Emphasis>)

Archaeobotanical analyses of charred seeds, fruit and wood charcoal from the residential part of the ez-Zantur area at Petra, Jordan, provide new data on the agricultural economy and use of the landscape in this famous merchant Nabataean city from the middle of the 2nd century bc to the beginning of the 5th century ad. The study is based on analyses of 7,640 whole and fragmented seeds, pips and fruit stones and 624 charcoal fragments sampled from household deposits. The results show that the food supply was based on common Mediterranean cultivated taxa such as cereals (Hordeum vulgare, Triticum aestivum/durum), pulses (Lens culinaris) and fruit (Olea europaea, Ficus carica, Vitis vinifera), which were probably cultivated both in the city and its hinterland. The by-products from the processing of cereals and fruit trees played a significant role in fuel supply, supplementing woody wild plants obtained from rocky slopes and the desert valley. The variety of fuel resources shows a major capacity to manage complex supply networks and perhaps the rarity of natural woodland cover. The existence of orchards within the city centre and notably olive groves is indicated in the Early Nabataean period (mid 2nd century to mid 1st century bc) but they expanded during the Classical Nabataean period (mid 1st century bc to 1st century ad), probably reflecting specialised fruit growing. Unusual plant remains such as Prunus armeniaca (apricot), P. persica (peach) and Juglans regia (walnut) are considered to be social indicators of prosperity. These archaeobotanical results fit with others from this region and match with the urbanization and social dynamics of the city of Petra.     

Tracing a bog-iron bloomery furnace in an adjacent lake-sediment record in Ängersjö, central Sweden,using pollen and geochemical signals

Recent studies of bloomery sites in Sweden indicate the amount of iron produced with this early low-technology smelter was greater than previously thought, which implies greater economic importance. Little is known about the history of bloomery technology, not least the timeframe over which individual bloomeries were operated, as well as their impact on the landscape because of resource consumption and pollution. In this study we performed pollen and geochemical analyses of the lake-sediment record from Rörtjärnen, which is 120 m from the remains of a documented bloomery [one radiocarbon date: ad 1300–1435 (1 σ)], in Ängersjö, Hälsingland. A surface-soil transect shows a limited geochemical signal only within 20 m of the bloomery, and the sediment pollen record provides little direct evidence of an active bloomery and is consistent with other studied sites in the area linked to forest grazing or cultivation. Instead, we find major changes in sediment geochemistry during ad 800–1200, centered on a unique peak in Pb at ad 1030–1060. These changes include, e.g., Si (biogenic) and P, together with changes in pollen (e.g., Betula, Picea, Cyperaceae), which together indicate disturbance in the forest and especially the adjoining fen. We attribute these changes to a period of bloomery-related activities predating the radiocarbon date of the charcoal from the bloomery, and suggest that date represents a late phase for the site.     

Seven Millennia of human impact as reflected in a high resolution pollen profile from the profundal sediments of Litzelsee,Lake Constance region,Germany

A profundal core from Litzelsee, a small cirque lake in the western Lake Constance region, was investigated by pollen analysis and dated radiometrically. The upper part of the core, chronologically between 5000 cal bc and 1850 ad, was sampled continuously, resulting in a total of 449 samples, each with a sum of 1,000 arboreal pollen grains. Also in this huge data set, rare taxa, normally lacking or very scarce in pollen profiles, were registered. The ecological evaluation of these, with a focus on anthropogenic indicators, sheds light on environmental and human impact history from the Neolithic to Modern times. Further, the results are put in a regional context, together with seven other mostly unpublished pollen profiles studied in the same way.     

Boreal forest dynamics in north-eastern Sweden during the last 10,000 years based on pollen analysis

A pollen record obtained from a 2.2-m sediment succession deposited in a small lake in the province of Västerbotten, north-eastern Sweden, reveals the presence of continuous forest cover since 8,500 calendar years before present (cal b.p.). Forest with abundant Pinus (pine) and Betula (birch) initially colonized the area, followed by a dominance of deciduous trees, primarily Betula, from ca. 8,000 to ca. 3,200 cal b.p. Pollen accumulation rates of Quercus (oak), Ulmus (elm) and Tilia (linden) suggest the possible local presence of these thermophilous tree species during this period. The climate gradually became colder and moister around 3,500 cal b.p. and an increased abundance of Sphagnum spores indicates paludification. Picea (spruce) became established around 3,200 cal b.p. and less than 500 years later this was the dominant tree species around the lake. The fire frequency as inferred from charcoal particles exhibits a general increase from ca. 3,000 cal b.p. with subsequent charcoal accumulation maxima at around 2,800 cal b.p., 1,700 cal b.p. and in recent time. The human influence on vegetation was significant during the last 200–300 years. Soil erosion increased substantially and fern spores amount to ca. 55% of the total pollen assemblage in the uppermost samples. These results suggest an extensive anthropogenic impact on the local forest ecosystem, with abundant logging, burning and ditching in the vicinity of the lake. Independent evidence of sub-recent human-induced environmental change is provided by historical accounts. Complementary information on catchment soil development and aquatic nutrient status was provided by records of magnetic susceptibility and elemental carbon, and nitrogen contents obtained from the same sediment core.     

Plant remains from the early modern garden of the manor of Kumpula,Helsinki, Finland: an alternative sampling method for macrofossil analysis

Garden history can be investigated through archaeobotanical research. This paper discusses the plant remains which were obtained from the soil of the historical garden of the manor of Kumpula in Helsinki, Finland. This study was an experiment to enable macrofossil analysis without archaeological excavations. The aim was to develop an alternative method for sampling for macrofossils also including radiocarbon dates, and to evaluate the usability, cost and functionality of this method. The character of the garden was also considered. The soil samples for macrofossil analysis were collected from the garden from three to eight different levels using an end-filling open-ended sampler. A total of 38 one litre soil samples from eight different pits yielded 2,036 identified macrofossils, mostly seeds. These comprised 63 different taxa, of which 26 were identified to species level with certainty. Taxa with more than 25 seeds found were Chelidonium majus, Chenopodium spp., Juncus spp., Rubus idaeus, Sambucus racemosa and Urtica dioica. Important species were Secale cereale and Hordeum vulgare. Nine AMS radiocarbon dates were obtained from macrofossil material from four different pits, giving results ranging from 1120–920 cal bc to cal ad 1680–1930 for charred wood, and from cal ad 1450–1640 to 1640–1930 for charred grains of Secale cereale and seeds of Chenopodium album. The sampling method proved to work reasonably well, considering the limitations of the sample size.     

Individualized,discrete event,simulations provide insight into inter- and intra-subject variability of extended-release,drug products

Objective

Develop and validate particular, concrete, and abstract yet plausible in silico mechanistic explanations for large intra- and interindividual variability observed for eleven bioequivalence study participants. Do so in the face of considerable uncertainty about mechanisms.

Methods

We constructed an object-oriented, discrete event model called subject (we use small caps to distinguish computational objects from their biological counterparts). It maps abstractly to a dissolution test system and study subject to whom product was administered orally. A subject comprises four interconnected grid spaces and event mechanisms that map to different physiological features and processes. Drugs move within and between spaces. We followed an established, Iterative Refinement Protocol. Individualized mechanisms were made sufficiently complicated to achieve prespecified Similarity Criteria, but no more so. Within subjects, the dissolution space is linked to both a product-subject Interaction Space and the GI tract. The GI tract and Interaction Space connect to plasma, from which drug is eliminated.

Results

We discovered parameterizations that enabled the eleven subject simulation results to achieve the most stringent Similarity Criteria. Simulated profiles closely resembled those with normal, odd, and double peaks. We observed important subject-by-formulation interactions within subjects.

Conclusion

We hypothesize that there were interactions within bioequivalence study participants corresponding to the subject-by-formulation interactions within subjects. Further progress requires methods to transition currently abstract subject mechanisms iteratively and parsimoniously to be more physiologically realistic. As that objective is achieved, the approach presented is expected to become beneficial to drug development (e.g., controlled release) and to a reduction in the number of subjects needed per study plus faster regulatory review.

     

Studies in the taxonomy of the Polypores II

The following genera are redefined:Albatrellus S. F. Gray,Heterobasidion Bref.,Haploporus Bond. et Sing. ex Sing.,Fomitopsis P. Karst. andRigidoporus Murrill two new subgenera are described:Polyporus subgen.Dendropolyporus Pouz. (type:Polyporus umbellatus) andRigidoporus subgen.Neooxyporus Pouz. (type:Polyporus latemarginatus); the genusOxyporus (Bourd. etGalz.)Donk is classified as a subgenus of the genusRigidoporus,Murrill and the generaBjerkandera P. Karst. andLeptoporus quél. are classified as subgenera of the genusTyromyces P. Karst. The new subfamilyAlbatrelloideae Pouz. (genera:Albatrellus andGrifola) is described and 14 new specific combinations are made. The new genusIrpicodon Pouz. (type:Irpex pendulus) is proposed.     

Production of <Emphasis Type="SmallCaps">d</Emphasis>-alanine from <Emphasis Type="SmallCaps">dl</Emphasis>-alanine using immobilized cells of <Emphasis Type="Italic">Bacillus subtilis</Emphasis> HLZ-68

Immobilized cells of Bacillus subtilis HLZ-68 were used to produce d-alanine from dl-alanine by asymmetric degradation. Different compounds such as polyvinyl alcohol and calcium alginate were employed for immobilizing the B. subtilis HLZ-68 cells, and the results showed that cells immobilized using a mixture of these two compounds presented higher l-alanine degradation activity, when compared with free cells. Subsequently, the effects of different concentrations of polyvinyl alcohol and calcium alginate on l-alanine consumption were examined. Maximum l-alanine degradation was exhibited by cells immobilized with 8% (w/v) polyvinyl alcohol and 2% (w/v) calcium alginate. Addition of 400 g of dl-alanine (200 g at the beginning of the reaction and 200 g after 30 h of incubation) into the reaction solution at 30 °C, pH 6.0, aeration of 1.0 vvm, and agitation of 400 rpm resulted in complete l-alanine degradation within 60 h, leaving 185 g of d-alanine in the reaction solution. The immobilized cells were applied for more than 15 cycles of degradation and a maximum utilization rate was achieved at the third cycle. d-alanine was easily extracted from the reaction solution using cation-exchange resin, and the chemical and optical purity of the extracted d-alanine was 99.1 and 99.6%, respectively.     

Safety of long-term dietary supplementation with <Emphasis Type="SmallCaps">l</Emphasis>-arginine in rats

This study was conducted with rats to determine the safety of long-term dietary supplementation with l-arginine. Beginning at 6 weeks of age, male and female rats were fed a casein-based semi-purified diet containing 0.61 % l-arginine and received drinking water containing l-arginine-HCl (0, 1.8, or 3.6 g l-arginine/kg body-weight/day; n = 10/group). These supplemental doses of l-arginine were equivalent to 0, 286, and 573 mg l-arginine/kg body-weight/day, respectively, in humans. After a 13-week supplementation period, blood samples were obtained from rats for biochemical analyses. Supplementation with l-arginine increased plasma concentrations of arginine, ornithine, proline, homoarginine, urea, and nitric oxide metabolites without affecting those for lysine, histidine, or methylarginines, while reducing plasma concentrations of ammonia, glutamine, free fatty acids, and triglycerides. l-Arginine supplementation enhanced protein gain and reduced white-fat deposition in the body. Based on general appearance, feeding behavior, and physiological parameters, all animals showed good health during the entire experimental period; Plasma concentrations of all measured hormones (except leptin) did not differ between control and arginine-supplemented rats. l-Arginine supplementation reduced plasma levels of leptin. Additionally, l-arginine supplementation increased l-arginine:glycine amidinotransferase activity in kidneys but not in the liver or small intestine, suggesting tissue-specific regulation of enzyme expression by l-arginine. Collectively, these results indicate that dietary supplementation with l-arginine (e.g., 3.6 g/kg body-weight/day) is safe in rats for at least 91 days. This dose is equivalent to 40 g l-arginine/kg body-weight/day for a 70-kg person. Our findings help guide clinical studies to determine the safety of long-term oral administration of l-arginine to humans.     

Glacial relics in the bryoflora of the highlands Českomoravská vrchovina (Bohemian-Moravian Highlands); Their habitat and cenotaxonomic value

The paper sums up the information which the author has so far collected about the habitats and phytocenotic conditions of the glacial relics ofScorpidium scorpioides (Hedw.) Limpr.,Calliergon trifarium (Web. etMohr.)Kindb.,Paludella squarrosa (Hedw.) Brid., andMeesia triquetra (Hook. etTayl.)Aongstr. in the Highlands ?eskomoravská vrchovina (Bohemian-Moravian Highlands) in Czechoslovakia. Simultaneously, it presents a survey of the localities in which the occurrence of these species has been ascertained up to now.     

Engineering an ATP-dependent <Emphasis Type="SmallCaps">d</Emphasis>-Ala:<Emphasis Type="SmallCaps">d</Emphasis>-Ala ligase for synthesizing amino acid amides from amino acids

We successfully engineered a new enzyme that catalyzes the formation of d-Ala amide (d-AlaNH₂) from d-Ala by modifying ATP-dependent d-Ala:d-Ala ligase (EC 6.3.2.4) from Thermus thermophilus, which catalyzes the formation of d-Ala-d-Ala from two molecules of d-Ala. The new enzyme was created by the replacement of the Ser293 residue with acidic amino acids, as it was speculated to bind to the second d-Ala of d-Ala-d-Ala. In addition, a replacement of the position with Glu performed better than that with Asp with regards to specificity for d-AlaNH₂ production. The S293E variant, which was selected as the best enzyme for d-AlaNH₂ production, exhibited an optimal activity at pH 9.0 and 40 °C for d-AlaNH₂ production. The apparent K _m values of this variant for d-Ala and NH₃ were 7.35 mM and 1.58 M, respectively. The S293E variant could catalyze the synthesis of 9.3 and 35.7 mM of d-AlaNH₂ from 10 and 50 mM d-Ala and 3 M NH₄Cl with conversion yields of 93 and 71.4 %, respectively. This is the first report showing the enzymatic formation of amino acid amides from amino acids.     

High-resolution palynology reveals the land use history of a Sami <Emphasis Type="Italic">renvall</Emphasis> in northern Sweden

The limited availability of historical and archaeological evidence means that much is still unknown about the development of Sami reindeer herding in Fennoscandia in both the recent and more distant past. To address this problem, high-resolution palynological analyses, ¹⁴C and ²¹⁰Pb dating were undertaken on two adjacent (<25 m apart) peat profiles collected at a recently abandoned reindeer gathering pen (renvall) near Jokkmokk (~66.6°N, 19.8°E) in the boreal forest of northern Sweden. The aim was to assess the impact of Sami reindeer herding on the local environment through a study of pollen, coprophilous fungal spores, microscopic charcoal and sedimentology. The samples collected from within an annex to the renvall indicate cycles of use and abandonment of the pen on a multi-decadal timescale between ~ad 1800–2008, most obviously in the coprophilous fungal spore archive. The pattern and timing of these cycles confirm events previously known only from oral histories. Although the local pollen assemblage zones associated with the phasing of activity were reproducible in a second peat core beyond the boundary of the renvall, the coprophilous fungal spore signal in this paired profile was much less distinctive, possibly due to the typically shorter dispersal distances for these microfossils in comparison to pollen grains.     

Application and microbial preparation of <Emphasis Type="SmallCaps">d</Emphasis>-valine

d-Valine is an important organic chiral source and has extensive industrial application, which is used as intermediate for the synthesis of agricultural pesticides, semi-synthetic veterinary antibiotics and pharmaceutical drugs. Its derivatives have shown great activity in clinical use, such as penicillamine for the treatment of immune-deficiency diseases, and actinomycin D for antitumor therapy. Fluvalinate, a pyrethroid pesticide made from d-valine, is a broad-spectrum insecticide with low mammalian toxicity. Valnemulin, a semi-synthetic pleuromutilin derivative synthesized from d-valine, is an antibiotic for animals. Moreover, d-valine is also used in cell culture for selectively inhibiting fibroblasts proliferation. Due to its widespread application, d-valine is gaining more and more attention and some approaches for d-valine preparation have been investigated. In comparison with other approaches, microbial preparation of d-valine is more competitive and promising because of its high stereo selectivity, mild reaction conditions and environmental friendly process. So far, microbial preparation of d-valine can be mainly classified into three categories: microbial asymmetric degradation of dl-valine, microbial stereoselective hydrolysis of N-acyl-dl-valine by d-aminoacylase, and microbial specific hydrolysis of dl-5-isopropylhydantoin by d-hydantoinase coupled with d-carbamoylase. In this paper, the industrial application of d-valine and its microbial preparation are reviewed.     

Increased productivity of <Emphasis Type="SmallCaps">l</Emphasis>-2-aminobutyric acid and total turnover number of NAD<Superscript>+</Superscript>/NADH in a one-pot system through enhanced thermostability of <Emphasis Type="SmallCaps">l</Emphasis>-threonine deaminase

Objective

To strengthen NADH regeneration in the biosynthesis of l-2-aminobutyric acid (l-ABA).

Results

l-Threonine deaminase (l-TD) from Escherichia coli K12 was modified by directed evolution and rational design to improve its endurance to heat treatment. The half-life of mutant G323D/F510L/T344A at 42 °C increased from 10 to 210 min, a 20-fold increase compared to the wild-type l-TD, and the temperature at which the activity of the enzyme decreased by 50% in 15 min increased from 39 to 53 °C. The mutant together with thermostable l-leucine dehydrogenase from Bacillus sphaericus DSM730 and formate dehydrogenase from Candida boidinii constituted a one-pot system for l-ABA biosynthesis. Employing preheat treatment in the one-pot system, the biosynthesis of l-ABA and total turnover number of NAD⁺/NADH were 0.993 M and 16,469, in contrast to 0.635 M and 10,531 with wild-type l-TD, respectively.

Conclusions

By using the engineered l-TD during endured preheat treatment, the one-pot system has achieved a higher productivity of l-ABA and total turnover number of coenzyme.

     

The variability of critical species ofLotus L. in Iran and in the neighbouring countries I. the circle ofL. corniculatus L. andL. gebelia Vent.

The region of Iran, Iraq, Afghanistan and the neighbouring countries is important for some groups of the speciesLotus L., especially those of the circle ofL. corniculatus L. andL. gebelia Vent. The first group is represented by the speciesL. corniculatus L. with 4 subspecies (3 of which are important for this region), andL. tenuis Waldst. etKit. which here attains the eastern boundary of the continuous area of distribution, and by the eastern speciesL. krylovii Schischk. etSerg. andL. rechingeri Chrtková-?ertová. The second group is represented by the speciesL. gebelia Vent.,L. michauxianus Ser. in DC. andL. libanoticus Boiss. their areas of distribution covering mostly those regions. Most of the species show considerable variability within the species.     

An optimized fed-batch culture strategy integrated with a one-step fermentation improves <Emphasis Type="SmallCaps">l</Emphasis>-lactic acid production by <Emphasis Type="Italic">Rhizopus oryzae</Emphasis>

In previous work, we proposed a novel modified one-step fermentation fed-batch strategy to efficiently generate l-lactic acid (l-LA) using Rhizopus oryzae. In this study, to further enhance efficiency of l-LA production through one-step fermentation in fed-batch cultures, we systematically investigated the initial peptone- and glucose-feeding approaches, including different initial peptone and glucose concentrations and maintained residual glucose levels. Based on the results of this study, culturing R. oryzae with initial peptone and glucose concentrations of 3.0 and 50.0 g/l, respectively, using a fed-batch strategy is an effective approach of producing l-LA through one-step fermentation. Changing the residual glucose had no obvious effect on the generation of l-LA. We determined the maximum LA production and productivity to be 162 g/l and 6.23 g/(l·h), respectively, during the acid production stage. Compared to our previous work, there was almost no change in l-LA production or yield; however, the productivity of l-LA increased by 14.3%.