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1.
Biotechnol Bioeng ; 119(8): 2142-2151, 2022 08.
Article in English | MEDLINE | ID: mdl-35451059

ABSTRACT

A novel fermentation process was developed in which renewable electricity is indirectly used as an energy source in fermentation, synergistically decreasing both the consumption of sugar as a first generation carbon source and emission of the greenhouse gas CO2 . As an illustration, a glucose-based process is co-fed with formic acid, which can be generated by capturing CO2 from fermentation offgas followed by electrochemical reduction with renewable electricity. This "closed carbon loop" concept is demonstrated by a case study in which cofeeding formic acid is shown to significantly increase the yield of biomass on glucose of the industrially relevant yeast species Yarrowia lipolytica. First, the optimal feed ratio of formic acid to glucose is established using chemostat cultivations. Subsequently, guided by a dynamic fermentation process model, a fed-batch protocol is developed and demonstrated on laboratory scale. Finally, the developed fed-batch process is tested and proven to be scalable at pilot scale. Extensions of the concept are discussed to apply the concept to anaerobic fermentations, and to recycle the O2 that is co-generated with the formic acid to aerobic fermentation processes for intensification purposes.


Subject(s)
Yarrowia , Carbon , Carbon Dioxide , Fermentation , Formates , Glucose
2.
ChemistryOpen ; 7(12): 995-1004, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30524925

ABSTRACT

We have quantum chemically explored the Diels-Alder reactivities of a systematic series of hetero-1,3-butadienes with ethylene by using density functional theory at the BP86/TZ2P level. Activation strain analyses provided physical insight into the factors controlling the relative cycloaddition reactivity of aza- and oxa-1,3-butadienes. We find that dienes with a terminal heteroatom, such as 2-propen-1-imine (NCCC) or acrolein (OCCC), are less reactive than the archetypal 1,3-butadiene (CCCC), primarily owing to weaker orbital interactions between the more electronegative heteroatoms with ethylene. Thus, the addition of a second heteroatom at the other terminal position (NCCN and OCCO) further reduces the reactivity. However, the introduction of a nitrogen atom in the backbone (CNCC) leads to enhanced reactivity, owing to less Pauli repulsion resulting from polarization of the diene HOMO in CNCC towards the nitrogen atom and away from the terminal carbon atom. The Diels-Alder reactions of ethenyl-diazene (NNCC) and 1,3-diaza-butadiene (NCNC), which contain heteroatoms at both the terminal and backbone positions, are much more reactive due to less activation strain compared to CCCC.

3.
Paleobiodivers Paleoenviron ; 98(3): 441-458, 2018.
Article in English | MEDLINE | ID: mdl-30956713

ABSTRACT

Seven new rodent faunas are described from the Pcinja and Babusnica-Koritnica basins of south-east Serbia. The geology of the Tertiary deposits in the Pcinja and Koritnica-Babusnica basins of south-east Serbia is briefly reviewed. The fossil content of the new vertebrate localities is listed, and an inventory of the rodent associations is presented. The rodent associations are late Eocene-early Oligocene in age, interpreted on biostratigraphical grounds. These are the first rodent faunas of that age from the Balkan area, an important palaeogeographic location between Europe and Asia. The Muridae, with the subfamilies Pseudocricetodontinae, Paracricetodontinae, Pappocricetodontinae, Melissiodontinae and ?Spalacinae, are dominant with eight genera, four of which are new. The diversity of the Melissiodontinae and Paracricetodontinae in the faunas suggests that these subfamilies originated in this region. The bi-lophodont cheek teeth occurring in the Oligocene assemblages are identified as the first record of the Diatomyidae outside of Asia. In light of the large amount of new data, the palaeogeographic setting and faunal turnover of the Eocene-Oligocene is discussed.

4.
Paleobiodivers Paleoenviron ; 98(3): 489-508, 2018.
Article in English | MEDLINE | ID: mdl-30956716

ABSTRACT

Three Paracricetodon species from the late Eocene locality Bustranje and the Early Oligocene localities Valnis, Strelac-1, -2, -3 and Raljin (south-east Serbia) are described; Paracricetodon dehmi Hrubesch, 1957 and two new species: Paracricetodon stojanovici and P. gracilis. A review of Paracricetodon species suggests that the species P. spectabilis, P. cadurcensis, P. dehmi, P. walgeri and P. wentgesi are primarily distinct in size. Paracricetodon kavakderensis and P. kodjayarmensis from Turkish Trace are considered junior synonyms of P. dehmi. The diversity and abundance of the Paracricetodontinae in the rodent assemblages from Serbia is not known from elsewhere and suggest that they underwent a radiation on the Serbian-Macedonian land area.

5.
Paleobiodivers Paleoenviron ; 98(3): 459-469, 2018.
Article in English | MEDLINE | ID: mdl-30956714

ABSTRACT

A new diatomyid genus and species, Inopinatia balkanica, from the early Oligocene of south-east Serbia is described, and the affinities between the Diatomyidae and Ctenodactylidae are discussed. Inopinatia balkanica nov. gen. nov. sp. seems to have retained its deciduous teeth throughout life just as all other species of the family. The only other diatomyid described from outside south-east Asia which is Pierremus explorator López-Antoñanzas, 2010 is transferred to the thryonomyid species Paraphiomys knolli López-Antoñanzas and Sen, 2005.

6.
Paleobiodivers Paleoenviron ; 98(3): 471-487, 2018.
Article in English | MEDLINE | ID: mdl-30956715

ABSTRACT

Isolated teeth of Melissiodontinae from two Eocene and four Oligocene localities in southeastern Serbia are described. One new genus and two new species are named. The study of the derived morphology of the cheek teeth and of the contrastingly primordial microstructure of the tooth enamel of this diverse material provides a glimpse into the early history of the subfamily. The supposedly Asian murid ancestor of the Melissiodontinae seems to have reached the Serbian-Macedonian land area during the early or middle Eocene, which is shortly after the split up of the Muridae and Dipodidae and before the 'Grande Coupure' of central and Western Europe. We interpret the rapid consequent specialisation of the morphology of the chewing apparatus of the Melissiodontinae as an adaptation to feeding on small invertebrates on the floor of the Eocene forest.

7.
J Med Chem ; 60(22): 9376-9392, 2017 11 22.
Article in English | MEDLINE | ID: mdl-29091431

ABSTRACT

Recently, a new class of reactivators of chemical warfare agent inhibited acetylcholinesterase (AChE) with promising in vitro potential was developed by the covalent linkage of an oxime nucleophile and a peripheral site ligand. However, the complexity of these molecular structures thwarts their accessibility. We report the compatibility of various oxime-based compounds with the use of the Ugi multicomponent reaction in which four readily accessible building blocks are mixed together to form a product that links a reactivating unit and a potential peripheral site ligand. A small library of imidazole and imidazolium reactivators was successfully synthesized using this method. Some of these compounds showed a promising ability to reactivate AChE inhibited by various types of CWA in vitro. Molecular modeling was used to understand differences in reactivation potential between these compounds. Four compounds were evaluated in vivo using sarin-exposed rats. One of the reactivators showed improved in vivo efficacy compared to the current antidote pralidoxime (2-PAM).


Subject(s)
Acetylcholinesterase/metabolism , Cholinesterase Reactivators/chemical synthesis , Cholinesterase Reactivators/pharmacology , Animals , Brain/metabolism , Cholinesterase Inhibitors/adverse effects , Cholinesterase Reactivators/administration & dosage , Cholinesterase Reactivators/pharmacokinetics , Humans , Imidazoles/administration & dosage , Imidazoles/chemical synthesis , Imidazoles/pharmacokinetics , Imidazoles/pharmacology , Kinetics , Male , Models, Molecular , Molecular Docking Simulation , Nerve Agents/adverse effects , Oximes/administration & dosage , Oximes/chemical synthesis , Oximes/pharmacokinetics , Oximes/pharmacology , Pralidoxime Compounds/pharmacology , Rats, Wistar , Sarin/adverse effects
8.
FEMS Yeast Res ; 17(5)2017 08 01.
Article in English | MEDLINE | ID: mdl-28899031

ABSTRACT

The recent start-up of several full-scale 'second generation' ethanol plants marks a major milestone in the development of Saccharomyces cerevisiae strains for fermentation of lignocellulosic hydrolysates of agricultural residues and energy crops. After a discussion of the challenges that these novel industrial contexts impose on yeast strains, this minireview describes key metabolic engineering strategies that have been developed to address these challenges. Additionally, it outlines how proof-of-concept studies, often developed in academic settings, can be used for the development of robust strain platforms that meet the requirements for industrial application. Fermentation performance of current engineered industrial S. cerevisiae strains is no longer a bottleneck in efforts to achieve the projected outputs of the first large-scale second-generation ethanol plants. Academic and industrial yeast research will continue to strengthen the economic value position of second-generation ethanol production by further improving fermentation kinetics, product yield and cellular robustness under process conditions.


Subject(s)
Ethanol/metabolism , Industrial Microbiology/methods , Metabolic Engineering/methods , Metabolic Networks and Pathways/genetics , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Fermentation , Lignin/metabolism
9.
Dalton Trans ; 46(19): 6433-6446, 2017 May 16.
Article in English | MEDLINE | ID: mdl-28470290

ABSTRACT

The synthesis and characterization, using NMR (1H and 13C), infrared spectroscopy, and X-ray crystallography, of the ethene and carbon monoxide copper(i) complexes of hydridotris(3,5-diphenylpyrazol-1-yl)borate ([TpPh2]-) and the two new ligands hydridotris(3,5-bis(1-naphthyl)pyrazol-1-yl)borate ([Tp(1Nt)2]-) and hydridotris(3,5-bis-(2-naphthyl)pyrazol-1-yl)borate ([Tp(2Nt)2]-) are described. X-ray crystal structures are presented of [Cu(TpPh2)(C2H4)] and [Cu(Tp(2Nt)2)(C2H4)]. The compound [Cu(TpPh2)(C2H4)] features interactions between the protons of the ethene ligand and the π-electron clouds of the phenyl substituents that make up the binding pocket surrounding the copper(i) center. These dipolar interactions result in strongly upfield shifted signals of the ethene protons in 1H-NMR. [Cu(Tp(1Nt)2)(CO)] and [Cu(Tp(2Nt)2)(CO)] were examined using infrared spectroscopy and were found to have CO stretching vibrations at 2076 and 2080 cm-1 respectively. The copper(i) carbonyl complexes form self-assembled monolayers when drop cast onto HOPG and thin multilayers of a few nanometers thickness when dip coated onto graphene. General macroscopic trends such as the different tendencies to crystallize observed in the complexes of the two naphthyl-substituted ligands appear to extend well to the nanoscale where a well-organized monolayer could be observed of [Cu(Tp(2Nt)2)(CO)].

11.
Plast Reconstr Surg ; 124(2): 364-371, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19644249

ABSTRACT

BACKGROUND: Mastopexy is generally regarded as having only a temporary effect. To prevent recurrent ptosis, mesh has been inserted successfully and safely, without oncological drawbacks, for almost three decades. Recently, preshaped three-dimensional knitted polyester mesh in different sizes was introduced to reinforce the breast during mastopexy. Until now, however, the physical and mechanical characteristics of mesh inserted in the female breast were unknown. METHODS: Polyester mesh removed from breasts in which it had been implanted was subjected to mechanical tests (two implants) and histological examination (five pieces of implant). RESULTS: Mesh induces only a thin layer of collagenous tissue together acting as a composite material. The collagen increases the in-plane stiffness of the mesh and enhances the overall strength. The composite is so strong that rupture or failure is extremely unlikely. The mesh composite shows high pliability, is therefore very supple and not palpable under the skin. CONCLUSION: Three-dimensional knitted polyester mesh appears to possess the proper mechanical characteristics to reinforce a ptotic breast during mastopexy.


Subject(s)
Mammaplasty/methods , Prostheses and Implants , Surgical Mesh , Adult , Aged , Breast/pathology , Female , Humans , Materials Testing , Middle Aged , Polyesters , Tensile Strength , Young Adult
12.
Aesthetic Plast Surg ; 32(5): 757-65, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18493817

ABSTRACT

BACKGROUND: Numerous techniques for mastopexy and breast reduction have been described, indicating the absence of a generally accepted method that fulfills the essential criteria for obtaining a pleasing, long-lasting result. All techniques using local tissue for reinforcement will eventually face recurrent ptosis because essentially the physical tissue properties are not altered. To overcome this, synthetic mesh has successfully been used to obtain permanent results. This method, however, was not generally accepted because of the fear of complications and of reduced oncologic survey and because no practical system was in place. Meanwhile, research showed that mesh could be safely introduced into the female breast. METHODS: An easy-to-use mesh implant was developed. It comes as a system consisting of three-dimensional, preshaped, feather-soft woven mesh in different sizes, and concomitant sizers to facilitate the insertion. It acts as an internal bra and is therefore named "the Internal Bra System." The mesh replaces the attenuated natural suspensory system of the breast, returning what was lost by nature. Indications are breast ptosis, breast hypertrophy with ptosis, and contralateral correction after reconstruction. RESULTS: A total of 170 patients (327 breasts) were treated with the longest follow-up of 4.5 years. No serious complications were encountered. Physical and X-ray examinations were still possible. No recurrent ptosis was observed and no scar hypertrophy. CONCLUSION: The Internal Bra System seems to have finally become the versatile way to obtain a predictable, pleasing, long-term result in mastopexy and breast reduction.


Subject(s)
Mammaplasty/methods , Prosthesis Design , Surgical Mesh , Adolescent , Adult , Aged , Breast Implants , Cohort Studies , Esthetics , Female , Follow-Up Studies , Humans , Mammaplasty/instrumentation , Middle Aged , Minimally Invasive Surgical Procedures/methods , Patient Satisfaction/statistics & numerical data , Polyesters , Prosthesis Fitting , Risk Assessment , Tensile Strength , Time Factors , Treatment Outcome , Young Adult
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