Combined effect of enzyme inducers and nitrate on selective lignin degradation in wheat straw by Ganoderma lobatum

Environmental Science and Pollution Research - Lignin is one of the main barriers to obtaining added-value products from cellulosic fraction of lignocellulosic biomass due to its random aromatic...     

Loss of an ecological baseline through the eradication of oyster reefs from coastal ecosystems and human memory

Oyster reefs form over extensive areas and the diversity and productivity of sheltered coasts depend on them. Due to the relatively recent population growth of coastal settlements in Australia, we were able to evaluate the collapse and extirpation of native oyster reefs (Ostrea angasi) over the course of a commercial fishery. We used historical records to quantify commercial catch of O. angasi in southern Australia from early colonization, around 1836, to some of the last recorded catches in 1944 and used our estimates of catch and effort to map their past distribution and assess oyster abundance over 180 years. Significant declines in catch and effort occurred from 1886 to 1946 and no native oyster reefs occur today, but historically oyster reefs extended across more than 1,500 km of coastline. That oyster reefs were characteristic of much of the coastline of South Australia from 1836 to 1910 appears not to be known because there is no contemporary consideration of their ecological and economic value. Based on the concept of a shifted baseline, we consider this contemporary state to reflect a collective, intergenerational amnesia. Our model of generational amnesia accounts for differences in intergenerational expectations of food, economic value, and ecosystem services of nearshore areas. An ecological system that once surrounded much of the coast and possibly the past presence of oyster reefs altogether may be forgotten and could not only undermine progress towards their recovery, but also reduce our expectations of these coastal ecosystems. La Pérdida de una Línea de Base Ecológica por Medio de la Erradicación de Arrecifes de Ostión de los Ecosistemas Costeros y la Memoria Humana     

Chromosome mosaicism and maternal cell contamination in chorionic villi

While chorionic villus sampling allows both early and rapid prenatal diagnosis of chromosome disorders, the accuracy of this technique has not been fully established. Maternal cell contamination and pseudomosaicism represent two major sources of diagnostic error. Combined use of both direct chromosome preparations and villus cultures is important in overcoming these problems. Direct preparations of villus tissue allow recognition of maternal cell contamination of villus cultures. Conversely, villus cultures yield higher resolution chromosomes and may be helpful in differentiating between true versus pseudomosaicism when two or more cell lines are identified in direct chromosome preparations. Preliminary data suggest that analysis of direct preparations from multiple individually processed villus fragments may also be of value in this regard. Until more experience is gained, mid-trimester amniocentesis should be offered to CVS patients when mosaicism is encountered.     

Influences on dusky dolphin (<Emphasis Type="Italic">Lagenorhynchus obscurus</Emphasis>) fission-fusion dynamics in Admiralty Bay,New Zealand

In societies characterized by a high degree of fission-fusion dynamics, individuals adjust their grouping patterns according to the shifting balance of costs and benefits associated with grouping. This study examines influences on fission-fusion dynamics for dusky dolphins (Lagenorhynchus obscurus) in Admiralty Bay, New Zealand. This area is an important foraging habitat for dusky dolphins during the winter and spring. Admiralty Bay has little predation risk, but nearshore mussel farms may infringe on available habitat. I used generalized estimating equations to determine the influences of coordinated foraging, predation risk, and presence of mussel farms on party size, rate of fission-fusion, and behavioral state. I conducted 168 boat-based group focal follows totaling 168 h. The proportion of individuals observed foraging was positively related to party size and rate of party fusion. Resting had no effect on party size and did not vary according to location. Near mussel farms, traveling decreased, and rate of party fission decreased. I conclude that (1) coordinated foraging strategies are a primary influence on fission-fusion dynamics within this population, (2) dolphins may respond to decreased predation risk by not adjusting party size or location during resting, and (3) areas near mussel farms are not used for traveling.     

Continuous automated imaging-in-flow cytometry for detection and early warning of Karenia brevis blooms in the Gulf of Mexico

Monitoring programs for harmful algal blooms (HABs) typically rely on time-consuming manual methods for identification and enumeration of phytoplankton, which make it difficult to obtain results with sufficient temporal resolution for early warning. Continuous automated imaging-in-flow by the Imaging FlowCytobot (IFCB) deployed at Port Aransas, TX has provided early warnings of six HAB events. Here we describe the progress in automating this early warning system for blooms of Karenia brevis. In 2009, manual inspection of IFCB images in mid-August 2009 provided early warning for a Karenia bloom that developed in mid-September. Images from 2009 were used to develop an automated classifier that was employed in 2011. Successful implementation of automated file downloading, processing and image classification allowed results to be available within 4 h after collection and to be sent to state agency representatives by email for early warning of HABs. No human illness (neurotoxic shellfish poisoning) has resulted from these events. In contrast to the common assumption that Karenia blooms are near monospecific, post-bloom analysis of the time series revealed that Karenia cells comprised at most 60–75 % of the total microplankton.     

Chinese villages and their sustainable future: the European Union-China-Research Project "SUCCESS"

China has 800,000 villages—one person out of seven on the globe is living in a Chinese rural settlement. Yet the global discussions about the situation in China is currently characterised by a disproportionate focus on the development of towns and until now circumstances have generally been neglected in the rural areas, where 70% of the Chinese population is still living. Within the 5 years of the SUCCESS project research, this set of actual problems has been considered and analysed under the principle of sustainability: “What to maintain?” “What to change?” were the overall research questions asked in the SUCCESS project; the researchers were looking for answers under a sustainability regime, respecting the need to raise the quality of life in the villages. Several interweaving processes were used to achieve results: the inter-disciplinary research process between many areas of expertise, the trans-disciplinary process between the researchers and the Chinese villagers, and a negotiation process that made the connection between these two processes.     

Stereochemistry of LinB-catalyzed biotransformation of δ-HBCD to 1R,2R,5S,6R,9R,10S-pentabromocyclododecanol

The haloalkane dehalogenase LinB from Sphingobium indicum B90A converts β-hexachlorocyclohexane (β-HCH), the most persistent HCH stereoisomer, to mono- and dihydroxylated metabolites. Recently, we reported that LinB also transforms α-, β- and γ-hexabromocyclododecanes (HBCDs), which are structurally related to HCHs. Here, we show that LinB catalyzes the hydroxylation of δ-HBCD to two pentabromocyclododecanols (PBCDOHs) and two tetrabromocyclododecadiols (TBCDDOHs). The stereochemistry of this enzymatic transformation was deduced from XRD crystal structure data of the substrate δ-HBCD and α₂-PBCDOH, one of the biotransformation products. Five stereocenters of δ-HBCD are unchanged but the one at C6 is converted to an alcohol with inversion from S- to R-configuration in a nucleophilic, S_N2-like substitution reaction. Only α₂-PBCDOH with the 1R,2R,5S,6R,9R,10S-configuration is obtained but not its enantiomer. With only two of the 64 PBCDOHs formed, these transformations indeed are regio- and stereoselective. A conformational analysis revealed that the triple-turn motive, which is predominant in δ-HBCD and in several other HBCD stereoisomers, is also found in the product. This shows that LinB preferentially converted reactive bromine atoms but not those in the conserved triple-turn motive. The widespread contamination with HCHs triggered the bacterial evolution of dehalogenases which acquired the ability to convert these pollutants and their metabolites. We here demonstrate that LinB of S. indicum also transforms HBCDs regio- and stereoselectively following a similar mechanism.     

Sediment phosphorus extractants for phosphorus-31 nuclear magnetic resonance analysis: a quantitative evaluation

The influence of pre-extractant, extractant, and post-extractant on total extracted amounts of P and organic P compound groups measured with 31P nuclear magnetic resonance (31P-NMR) in lacustrine sediment was examined. The main extractants investigated were sodium hydroxide (NaOH) and sodium hydroxide ethylenediaminetetraacetic acid (NaOH-EDTA) with bicarbonate buffered dithionite (BD) or EDTA as pre-extractants. Post extractions were conducted using either NaOH or NaOH-EDTA, depending on the main extractant. Results showed that the most efficient combination of extractants for total P yield was NaOH with EDTA as pre-extractant, yielding almost 50% more than the second best procedure. The P compound groups varying the most between the different extraction procedures were polyphosphates and pyrophosphates. NaOH with BD as pre-extractant was the most efficient combination for these compound groups.