bluuebunny/crossref_metadata_2025_split huggingface dataset:
Vegetation restoration improved aggregation stability and aggregated-associated carbon preservation in the karst areas of Guizhou Province, southwest China
Authors: Yang Hui , Long Hui , Li Xuemei , Luo Xiulong , Liao Yuanhang , Wang Changmin , Cai Hua , Shu Yingge 
Published: January 2024

Background
The change in the soil carbon bank is closely related to the carbon dioxide in the atmosphere, and the vegetation litter input can change the soil organic carbon content. However, due to various factors, such as soil type, climate, and plant species, the effects of vegetation restoration on the soil vary. Currently, research on aggregate-associated carbon has focused on single vegetation and soil surface layers, and the changes in soil aggregate stability and carbon sequestration under different vegetation restoration modes and in deeper soil layers remain unclear. Therefore, this study aimed to explore the differences and relationships between stability and the carbon preservation capacity (CPC) under different vegetation restoration modes and to clarify the main influencing factors of aggregate carbon preservation.

Methods
Grassland (GL), shrubland (SL), woodland (WL), and garden plots (GP) were sampled, and they were compared with farmland (FL) as the control. Soil samples of 0–40 cm were collected. The soil aggregate distribution, aggregate-associated organic carbon concentration, CPC, and stability indicators, including the mean weight diameter (MWD), fractal dimension (D), soil erodibility (K), and geometric mean diameter (GMD), were measured.

Results
The results showed that at 0–40 cm, vegetation restoration significantly increased the >2 mm aggregate proportions, aggregate stability, soil organic carbon (SOC) content, CPC, and soil erosion resistance. The >2 mm fractions of the GL and SL were at a significantly greater proportion at 0–40 cm than that of the other vegetation types but the CPC was only significantly different between 0 and 10 cm when compared with the other vegetation types (P < 0.05). The >2 mm aggregates showed a significant positive correlation with the CPC, MWD, and GMD (P < 0.01), and there was a significant negative correlation with the D and K (P < 0.05). The SOC and CPC of all the vegetation types were mainly distributed in the 0.25–2 mm and <0.25 mm aggregate fractions. The MWD, GMD, SOC, and CPC all gradually decreased with increasing soil depth. Overall, the effects of vegetation recovery on soil carbon sequestration and soil stability were related to vegetation type, aggregate particle size, and soil depth, and the GL and SL restoration patterns may be more suitable in this study area. Therefore, to improve the soil quality and the sequestration of organic carbon and reduce soil erosion, the protection of vegetation should be strengthened and the policy of returning farmland to forest should be prioritized.
Gaining more from doing less? The effects of a one-week deload period during supervised resistance training on muscular adaptations
Authors: Coleman Max , Burke Ryan , Augustin Francesca , Piñero Alec , Maldonado Jaime , Fisher James P. , Israetel Michael , Androulakis Korakakis Patroklos , Swinton Paul , Oberlin Douglas , Schoenfeld Brad J. 
Published: January 2024

Background
Based on emerging evidence that brief periods of cessation from resistance training (RT) may re-sensitize muscle to anabolic stimuli, we aimed to investigate the effects of a 1-week deload interval at the midpoint of a 9-week RT program on muscular adaptations in resistance-trained individuals.

Methods
Thirty-nine young men (n = 29) and women (n = 10) were randomly assigned to 1 of 2 experimental, parallel groups: An experimental group that abstained from RT for 1 week at the midpoint of a 9-week, high-volume RT program (DELOAD) or a traditional training group that performed the same RT program continuously over the study period (TRAD). The lower body routines were directly supervised by the research staff while upper body training was carried out in an unsupervised fashion. Muscle growth outcomes included assessments of muscle thickness along proximal, mid and distal regions of the middle and lateral quadriceps femoris as well as the mid-region of the triceps surae. Adaptions in lower body isometric and dynamic strength, local muscular endurance of the quadriceps, and lower body muscle power were also assessed.

Results
Results indicated no appreciable differences in increases of lower body muscle size, local endurance, and power between groups. Alternatively, TRAD showed greater improvements in both isometric and dynamic lower body strength compared to DELOAD. Additionally, TRAD showed some slight psychological benefits as assessed by the readiness to train questionnaire over DELOAD.

Conclusion
In conclusion, our findings suggest that a 1-week deload period at the midpoint of a 9-week RT program appears to negatively influence measures of lower body muscle strength but has no effect on lower body hypertrophy, power or local muscular endurance.
The Study of the Effect of Surfactants on Copper Codeposition with SiC Nano Particulate from Deep Eutectic Solvent Ionic Liquids (Ethaline)
Authors: Ttaib K. El , Benhmid A. 
Published: January 2024

Here we investigate the electrolytic deposition of copper and copper nano composites in the absence and the presence of two types of surfactants: cationic which is sodium dodecyl sulphate (SDS) and the other type is cetyl trimethyl ammonium bromide (CTAB) from a solution of the metal chloride salt in ethylene glycol–choline chloride based eutectics. The SEM images and EDAX analysis allow in situ quantification or particulate inclusion. It is quite interesting to perceive that the composition of composite material was strongly dependent on the amount of species suspended in solution. Again the data here has revealed that the majority of material was dragged onto the surface rather than settling on to it. The distribution of the composite material was found to be even throughout the coating. This technology is important because it facilitates deposition of bright copper coatings without co-ligands such as cyanide which is not friendly environment.
Analysing Decadal Land Use Land Cover Dynamics in the Sub-Upper Krishna Basin of Maharashtra, India Using Remote Sensing and GIS
Authors: Karale Omkar Sunil , Gavit B. K. , Bhat Adarsha Gopalakrishna , Paradkar Vinayak , Mukherjee Sweety , Gupta Anand 
Published: January 2024

Aims: This study was conducted to examine Land Use Land Cover (LULC) dynamics in Maharashtra’s sub-upper Krishna basin from 2009 to 2019 using remote sensing and geographical information system (GIS), focusing on water bodies, vegetation, soil, settlements, and their changes.
Study Design: Employing remote sensing and GIS for LULC mapping (2009-2019) the study used a maximum likelihood classifier in supervised classification, identifying six land use categories: water bodies, open shrubs, forests, agricultural land, settlements, and fallow land.
Place and Duration of Study: It was conducted in the sub-upper Krishna basin, Maharashtra, over ten years’ data (2009-2019).
Methodology: The study utilised satellite remote sensing and GIS tools for LULC mapping. A supervised classification was applied with a maximum likelihood classifier to categorize land. The changes in water bodies, open shrubs, forests, agricultural land, settlements, and fallow land were analysed using GIS approach.
Results: It was seen that, over the decade, fallow land decreased by 3.03%, while agricultural land and settlements grew by 7.32% and 4.3%, respectively. Tree cover increased by 9.85%, water bodies by 0.93%, and open scrubland decreased by 1.77%. Institutional factors, easier water access, and technological and economic factors drove these changes.
Conclusion: The study advocates the effective use of satellite remote sensing to monitor LULC changes, identifying key drivers, including institutional and technological factors, contributes to sustainable development planning. The findings aid predictions for future land use changes, supporting effective land management and conservation strategies in the region.
Enzymatic Discrimination of 2‐Acetamido‐2‐deoxy‐D‐mannopyranose‐Containing Disaccharides Using β‐N‐Acetylhexosaminidases
Authors: Hušáková Lucie , Herkommerová‐Rajnochová Eva , Semeňuk Tomáš , Kuzma Marek , Rauvolfová Jana , Přikrylová Věra , Ettrich Rüdiger , Plíhal Ondřej , Bezouška Karel , Křen Vladimír 
Published: June 2003

AbstractAbstract: β‐N‐Acetylhexosaminidase from Aspergillus oryzae selectively discriminates mixture of the disaccharides GlcNAcβ(1→4)GlcNAc (1) and GlcNAcβ(1→4)ManNAc (2). N,N′‐Diacetylchitobiose (1) was selectively hydrolyzed by β‐N‐acetylhexosaminidase, whereas its C‐2 epimer (2) was completely resistant to the enzyme hydrolysis. Analogous discrimination was observed also with GalNAcβ(1→4)GlcNAc (3) and GalNAcβ(1→4)ManNAc (4). β‐N‐Acetylhexosaminidases from A. terreus, A. flavus, bovine kidney and bovine epididymis displayed the same selectivity, whereas the enzymes from A. sojae, A. tamarii, Penicillium brasilianum, P. oxalicum, P. funiculosum, P. multicolor, Talaromyces flavus and jack beans hydrolyzed both types of disaccharides. Molecular modelling of β‐N‐acetylhexosaminidase from A. oryzae CCF 1066 and docking experiments with both types of disaccharides revealed that the ManNAc residue causes distortion of disaccharide molecule resulting in a steric conflict with a Trp482 that causes diminished stabilization of the oxazolinium transition state by extending the distance of Asp345 in the active site. Both ManNAc‐containing disaccharides 2 and 4 dock with similar steric energies into the active site but without cleaving and also without notable inhibition. This novel phenomenon enables also the preparative production of both disaccharides 2 and 4 starting from N, N'‐diacetylchitobiose (1) or GalNAcβ(1→4)GlcNAc (3) followed by Lobry de Bruyn–Albreda van Ekenstein C‐2 epimerization catalyzed by Ca(OH)2. The resultant mixture of the respective epimers 1, 2 or 3, 4 that is hardly separable by, e.g., analytical HPLC can be treated with the β‐N‐acetylhexosaminidase from A. oryzae and the mixture of monosaccharides and target disaccharide can be easily separated using gel filtration.
Enantiomerically Pure Octahydronaphthalenone and Octahydroindenone: Elaboration of the Substrate Overcame the Specificity of Yeast‐Mediated Reduction
Authors: Fuhshuku Ken‐ichi , Tomita Mina , Sugai Takeshi 
Published: June 2003

AbstractSubstrate specificity on the reduction of bicyclic diketones with a yeast strain, Torulaspora delbrueckii IFO10921, was investigated. Although this yeast efficiently reduces the isolated carbonyl group involved in the (S)‐enantiomer of Wieland–Miescher ketone with high enantioselectivity (E=126), the introduction of a substituent on the octahydronaphthalene skeleton as well as the structural change into an octahydroindene skeleton retarded the enzymatic reduction and the enantioselectivity fell to E=5–16. Further structural variation into a bicyclo[3.3.0] skeleton led to an exclusive 1,4‐conjugate reduction of the α,β‐unsaturated carbonyl group, and the above results suggested the participation of plural oxidoreductive enzymes in the whole cell. In turn, among the 2,2‐disubstituted cycloalkanediones there were found good substrates to give the corresponding hydroxy ketone equivalents by yeast‐mediated reduction. The products were isolated as cyclic hemiacetals, such as (1S,6S)‐3‐ethyl‐3‐hydroxy‐6‐methyl‐2‐oxabicyclo[4.4.0]decan‐7‐one and (1S,6S)‐3‐hydroxy‐3,6‐dimethyl‐2‐oxabicyclo[4.3.0]nonan‐7‐one. In addition, the reduction worked well with use of an air‐dried, long‐term preservable cell preparation. The subsequent chemical transformation warranted the stereochemistry and the stereochemical purity of the products, which are related to octahydronaphthalenone and octahydroindenone systems that, in turn, are of considerable value as starting materials for terpenoid synthesis.
Fluorogenic Cyanohydrin Esters as Chiral Probes for Esterase and Lipase Activity
Authors: Leroy Emmanuel , Bensel Nicolas , Reymond Jean‐Louis 
Published: June 2003

AbstractFluorogenic cyanohydrin esters were prepared that release the fluorescent product umbelliferone by secondary decomposition of the primary cyanohydrin reaction product by cyanide elimination to the aldehyde and subsequent β‐elimination. Whereas butyrate 1b and octanoate 1d show the highest reaction rates with enzymes, the highest relative rates above the non‐catalyzed background reaction are achieved with pivalate 1c and benzoate 1e. Enantioselective reactions are detected when the conversion stabilizes at 50% of the maximum fluorescence release, and enantioselectivity is confirmed by chiral‐phase HPLC analysis of the unreacted cyanohydrin ester substrate.
New Routes to Chiral Evans Auxiliaries by Enzymatic Desymmetrisation and Resolution Strategies
Authors: Neri Claudia , Williams Jonathan M. J. 
Published: June 2003

AbstractThis paper describes how enantiomerically enriched Evans auxiliaries can be successfully prepared by either an enzymatic desymmetrisation strategy or an asymmetric synthesis using racemic auxiliaries and an enzymatic resolution. Desymmetrisation of N‐Boc‐protected serinol has been achieved in good yield and high enantiomeric excess using porcine pancreas lipase. This has been exploited in different ways to prepare enantiomerically enriched (4R)‐ and (4S)‐substituted 2‐oxazolidinones. In another approach to asymmetric synthesis, starting from a racemic Evans auxiliary, by means of a diastereoselective aldol reaction coupled with a lipase‐catalysed resolution, we achieved the preparation of enantiomerically enriched β‐hydroxy acids and enantiomerically enriched 2‐oxazolidinones.
Biocatalytic Hydrolysis of 3‐Hydroxyalkanenitriles to 3‐Hydroxyalkanoic Acids
Authors: Hann Eugenia C. , Sigmund Amy E. , Fager Susan K. , Cooling Frederick B. , Gavagan John E. , Ben‐Bassat Arie , Chauhan Sarita , Payne Mark S. , Hennessey Susan M. , DiCosimo Robert 
Published: June 2003

AbstractMicrobial catalysts having a combination of nitrile hydratase and amidase activities had a significantly‐higher specific activity for hydrolysis of 3‐hydroxyalkanenitriles than microbial nitrilase catalysts. Comamonas testosteroni 22–1, Dietzia sp. ADL1 and Comamonas testosteroni 5‐MGAM‐4D nitrile hydratase/amidase biocatalysts each hydrolyzed 3‐hydroxyvaleronitrile to 3‐hydroxyvaleric acid (as the ammonium salt) in 99–100% yields, but in consecutive batch reactions with catalyst recycle, alginate‐immobilized C. testosteroni 5‐MGAM‐4D had superior enzyme stability and volumetric productivity. In a series of 85 consecutive batch reactions with biocatalyst recycle for the production of 1.0 M 3‐hydroxyvaleric acid, the recovered nitrile hydratase and amidase activities in the final reaction were 29% and 40%, respectively, of the initial activities. The catalyst productivity for this series of reactions was 670 g 3‐hydroxyvaleric acid/g dry cell weight (50 g 3‐hydroxyvaleric acid/g biocatalyst bead), and the volumetric productivity of the initial reaction in the series was 44 g 3‐HVA/L/h. Similar results were obtained with alginate‐immobilized C. testosteroni 5‐MGAM‐4D for the hydrolysis of 3‐hydroxybutryonitrile and 3‐hydroxypropionitrile to the corresponding 3‐hydroxyalkanoic acid ammonium salts.
Vanadium Chloroperoxidase as a Catalyst for Hydrogen Peroxide Disproportionation to Singlet Oxygen in Mildly Acidic Aqueous Environment
Authors: Renirie Rokus , Pierlot Christel , Aubry Jean‐Marie , Hartog Aloysius F. , Schoemaker Hans E. , Alsters Paul L. , Wever Ron 
Published: June 2003

AbstractChemiluminescence studies show that the enzyme vanadium chloroperoxidase from the fungus Curvularia inaequalis is a highly efficient catalyst for the production of singlet oxygen from hydrogen peroxide in a mildly acidic aqueous environment, with a maximum turnover frequency of 100 s−1 with respect to H2O2 consumption. The enzyme studied here can be regarded as a supplementary catalyst to inorganic molybdate, which operates in basic aqueous media. The enzyme system is 103 – 104 times faster than the molybdate system when compared at their optimal pH. The enzyme is very stable against singlet oxygen, in contrast to heme‐containing peroxidases which, due to inactivation by singlet oxygen, only produce a short burst, presumably by oxidation of the labile cofactor. The vanadium chloroperoxidase was compared with vanadium bromoperoxidase from the seaweed Ascophyllum nodosum and was found to be even more stable; it is stable towards a continuous flow of singlet oxygen for at least 1 hour and also it is not inactivated by 500 mM H2O2. An important difference with vanadium bromoperoxidase is that the vanadium chloroperoxidase is able to effectively use chloride as a cocatalyst (20 s−1) instead of bromide. This offers an important advantage from an application point of view; using chloride, no side products are observed when the chemical trap anthracene‐9,10‐bis(ethanesulphonate) is fully converted by singlet oxygen into its corresponding endoperoxide. By contrast, when bromide is used, 20% side product is formed. During the conversion the enzyme remains fully stable for 25,000 turnovers.
Enzymatic Racemisation and its Application to Synthetic Biotransformations
Authors: Schnell Barbara , Faber Kurt , Kroutil Wolfgang 
Published: June 2003

AbstractIn contrast to kinetic resolution, where only 50% of the racemic starting material can be converted into the desired product and where the remaining ‘wrong' enantiomer has to be considered as waste, so‐called deracemisation processes allow the production of a single stereoisomeric product from racemic starting material. In this context, the use of environmentally benign methods for biocatalytic racemisation holds great potential. The small and largely overlooked group of racemases (EC 5.1.X.X), which are increasingly being used for dynamic kinetic resolution or in auxiliary biocatalytic recycling processes, are reviewed with respect to their properties, their substrate tolerance and their biocatalytic potential.
Remote Effects Modulating the Spin Equilibrium of the Resting State of Cytochrome P450cam –An Investigation Using Active Site Analogues
Authors: Lochner Martin , Mu Linjing , Woggon Wolf‐D. 
Published: June 2003

AbstractThe crystal structure of the resting state of cytochrome P450cam (CYP101), a heme thiolate protein, shows a cluster of six water molecules in the substrate binding pocket, one of which is coordinating to iron(III) as sixth ligand. The resting state is low‐spin and changes to high‐spin when substrate camphor binds and H2O is removed. In contrast to the protein, previously synthesised enzyme models such as H2OFeIII(porph)(ArS−) were shown to be purely high‐spin. Iron(S−)porphyrins with different distal sites mimicking proposed remote effects have been prepared and studied by cw‐EPR. The results indicate that the low‐spin of the resting state of P450cam is due to the fact that the water molecule coordinating to iron has an OH−‐like character because of hydrogen bonding and polarisation of the water cluster, respectively.
The Donor Substrate Spectrum of Recombinant Sucrose Synthase 1 from Potato for the Synthesis of Sucrose Analogues
Authors: Römer Ulrike , Rupprath Carsten , Elling Lothar 
Published: June 2003

AbstractThe donor substrate spectrum of recombinant sucrose synthase 1 (SuSy1) from potato was studied in order to synthesise novel sucrose analogues. With D‐fructose as acceptor substrate SuSy1 accepts a variety of UDP‐activated sugars, e.g., UDP‐N‐acetyl‐α‐D‐glucosamine (UDP‐GlcNAc, 2) (100%), UDP‐α‐D‐glucuronic acid (UDP‐GlcA, 3) (32%), UDP‐α‐D‐xylose (UDP‐Xyl, 4) (39%), UDP‐α‐D‐galactose (UDP‐Gal, 5) (23%), and UDP‐N‐acetyl‐α‐D‐galactosamine (UDP‐GalNAc, 6) (23%). The kinetic analyses revealed that the non‐natural donors 2 (kcat/Km 1.2 s−1 mM−1) and 5 (kcat/Km 0.01 s−1 mM−1) were relative poor substrates compared to UDP‐Glc 1 (kcat/Km 310.4 s−1 mM−1). UDP‐GlcNAc was used in a preparative synthesis to produce 188 mg (0.5 mmol) 2‐acetamido‐2‐deoxy‐D‐glucopyranosyl‐β‐D‐fructofuranoside (9). The sucrose analogue 9 was not hydrolysed by invertase.
Second Generation Sol‐Gel Encapsulated Lipases: Robust Heterogeneous Biocatalysts
Authors: Reetz Manfred T. , Tielmann Patrick , Wiesenhöfer Wolfgang , Könen Werner , Zonta Albin 
Published: June 2003

AbstractThe original procedure for the encapsulation of lipases in sol‐gel materials produced by the fluoride‐catalyzed hydrolysis of mixtures of RSi(OCH3)3 and Si(OCH3)4 has been improved considerably. This involves higher enzyme loading, variation of the alkylsilane precursor, and the use of additives such as isopropyl alcohol, 18‐crown‐6, Tween 80®, methyl‐β‐cyclodextrin and/or KCl. A dramatic increase in enzyme activity is observed. The sol‐gel lipase immobilizates are also excellent catalysts in the kinetic resolution of chiral alcohols and amines, recycling without any substantial loss in enantioselectivity and a residual activity of 70% being possible even after 20 reaction cycles.
Nitrile and Amide Biotransformations for Efficient Synthesis of Enantiopure gem‐Dihalocyclopropane Derivatives
Authors: Wang Mei‐Xiang , Feng Guo‐Qiang , Zheng Qi‐Yu 
Published: June 2003

AbstractCatalyzed by Rhodococcus sp. AJ270 microbial cells, trans‐2,2‐dihalo‐3‐phenylcyclopropanecarbonitriles and ‐amides underwent enantioselective hydrolysis under very mild conditions. Both the efficiency and enantioselectivity of the nitrile hydratase and amidase involved in the cells were strongly determined by the nature of the halogen substituent. The synthetic utility of the biocatalytic process was illustrated by an efficient and multi‐gram scale biotransformation and synthesis of enantiopure 2,2‐dichloro‐3‐phenylcyclopropanecarboxylic acid and amide in both enantiomeric forms.
Penicillin Acylase Catalysed Synthesis of Ampicillin in Hydrophilic Organic Solvents
Authors: van Langen Luuk M. , Oosthoek Natasja H. P. , van Rantwijk Fred , Sheldon Roger A. 
Published: June 2003

AbstractPenicillin acylase (EC 3.5.1.11) from Alcaligenes faecalis, immobilised as a cross‐linked enzyme aggregate (CLEA), catalysed the synthesis of ampicillin in water‐miscible organic solvents at low water concentrations. Below 4% water (v/v) no reaction was observed, showing the crucial role of water in maintaining the activity of penicillin acylase. The initial value of S/H was strongly affected by the nature of the solvent, but the effect of the water content was slight in the studied range of 4 to 15%. A reaction in acetonitrile containing 8% water afforded ampicillin in up to 86% yield.
Novel Hydrolases from Thermophilic Filamentous Fungi for Enantiomerically and Enantiotopically Selective Biotransformations
Authors: Bódai Viktória , Peredi Réka , Bálint József , Egri Gabriella , Novák Lajos , Szakacs György , Poppe László 
Published: June 2003

AbstractFourteen thermophilic filamentous fungi were cultivated on two shake flask media and the supernatants were assayed for lipase/carboxylesterase activities using olive‐oil, p‐nitrophenyl palmitate and p‐nitrophenyl butyrate as substrates. The crude enzyme powders (acetone precipitated supernatants) were tested as biocatalysts in organic solvents. Kinetic resolution of racemic 1‐phenylethanol (rac‐1) and desymmetrisation of 2‐acyloxypropan‐1,3‐diols (3a, b) by acetylation with vinyl acetate were chosen for testing the biocatalytic abilities of these preparations. The tested biocatalysts proved to be comparable to the commercially available enzymes with respect to the degree of enantiomer selectivity, whereas they exhibited a wider range of enantiotopic selectivity than the most common commercial enzymes.