347 research outputs found
Quantitative Analysis of the Intramedullary Arterial Supply of the Feline Tibia: is There a Causal Relationship to Delayed and Nonunion Fracture Healing?
Clinical observations suggest that feline tibial fractures are prone to delayed union and nonunion healing complications. This study sought to quantitatively describe the intramedullary arterial supply of the adult feline tibia and determine if the arterial supply is different from that of adult small dogs, who seemingly do not exhibit the same rates of delayed and nonunion fracture healing. Our null hypothesis was that the intramedullary arterial density and diameter of the nutrient artery in the adult feline tibia was the same as the age and size matched dog. Using microvascular injection and modified Spalteholz techniques, cadaveric feline and canine pelvic limbs were prepared to characterize the intramedullary arterial supply of the tibia. Processed specimens were evaluated using the ImageJ morphometric program. Statistical comparisons were made between cats and dogs for the intramedullary arterial density and diameter of the nutrient artery. There was no significant difference in the intramedullary arterial density between dog and cat tibiae. The feline nutrient artery diameter (0.5497 ± 0.0552mm) was significantly different than the canine nutrient artery (0.2976 ± 0.0423mm) in the distal section of bone. Dogs subjectively exhibited more branching vessels in the distal and mid-diaphyseal bone sections. Delayed fracture healing in the feline tibia does not appear to be due to diminished intramedullary arterial supply. However, a lack of diffuse arborization of the arterial supply to the cortex of the mid-diaphyseal and distal feline tibia may explain, in part, why feline tibial delayed or nonunions may be more common than those in dogs.Veterinary Pathobiology Science
Interactions and Implications of a Collector Well with a River in an Unconfined Aquifer with Regional Background Flow
Ranney radial collector wells consist of an array of horizontal lateral wells arranged radially around and connected to the base of a vertical well. They offer numerous advantages over traditional vertical wells with application in both the petroleum industry and hydrologic sciences. This study improved the understanding of the interaction of collector wells and the aquifers/reservoirs they tap by numerically modeling flux exchanges between a collector well and a river in an unconfined aquifer with regional background flow. Modeling demonstrated that flux along each horizontal lateral increased with distance from the vertical well stem following a third order polynomial function. Ultimately these models demonstrated that in the collector well/aquifer/river system, the pumping rate of the collector well was the dominant factor in controlling flux between the river and aquifer under various conditions. This study can be used to project the maximum allowable pumping rate without causing an initially gaining river to become a losing river
An empirical study of the relations between leadership, social support networks, task autonomy and emotions in a technical work environment
The world in which we live is hyper-dynamic with multiple inputs, outputs and
expectations. As it relates to the fast pace of corporate America, customers
want products and services within a tighter market window, with no defects and
for lower costs. Stakeholders insist that managers do more with less human and financial resources yet more aggressive technological and sales
goals. These realities translate into a more complex work environment in that the
emotional toll of pending economic outcomes act to motivate or paralyze the
very engine designed to produce the desired outcomes the employees.
The body of work presented in this dissertation directly addresses the empirical
relationship between the perceptions of the work context factors of leadership,
task autonomy and social support networks with respect to the positive and negative emotions of the employees of the engineering firm that participated in
this study. The empirical results from this research indicate that a positive and
significant interrelationship does exist among the factors examined in this study.
The employees studied included 249 middle to upper level managers of whom
78.7% were men and 21.3% were women. The range of years of experience for
the participants varied from new hire to more than 20 years. Homogeneity of
Variance tests confirms the validity of comparative analysis for the segmented
data population. Multivariate statistics were used to address the four research
questions. The strongest correlations occurred for the subgroups of women and
non-managers with respect to the relationship of social support networks and
positive emotions. Until now, there has been no empirical research linking the
social support networks factor directly to emotions
Studies on the selective reduction of the amide link of acyclic and macrocyclic amidoketals. Unexpected cleavage and trans -acetalization with Red-Al®
Selective reduction of the amide moiety of acyclic and macrocyclic amidoketals was studied in presence of various reagents (BH3 · Me2S, iBuAlH2, Red-Al®, LiAlH4). The best results were obtained with lithium aluminium hydride in the presence of triethylamine traces, whereas borane dimethyl sulfide gave rise to a partial ketal reduction of the acyclic compound and Red-Al® to a cleavage of the macrocyclic molecule accompanied by an unexpected trans-acetalization
HiSpOD: probe design for functional DNA microarrays.
International audienceMOTIVATION: The use of DNA microarrays allows the monitoring of the extreme microbial diversity encountered in complex samples like environmental ones as well as that of their functional capacities. However, no probe design software currently available is adapted to easily design efficient and explorative probes for functional gene arrays. RESULTS: We present a new efficient functional microarray probe design algorithm called HiSpOD (High Specific Oligo Design). This uses individual nucleic sequences or consensus sequences produced by multiple alignments to design highly specific probes. Indeed, to bypass crucial problem of cross-hybridizations, probe specificity is assessed by similarity search against a large formatted database dedicated to microbial communities containing about 10 million coding sequences (CDS). For experimental validation, a microarray targeting genes encoding enzymes involved in chlorinated solvent biodegradation was built. The results obtained from a contaminated environmental sample proved the specificity and the sensitivity of probes designed with the HiSpOD program. AVAILABILITY: http://fc.isima.fr/~g2im/hispod/
Conformational analysis of new 14-membered ring diketal dilactam macrocycles: molecular mechanics, liquid and solid state NMR studies
A conformational study of new diversely substituted 14-membered diketal dilactam macrocycles was conducted by NMR spectroscopy in liquid and solid states, molecular mechanics calculations and, for one compound, a previous X-ray analysis. The results obtained by the different techniques show that the conformations depend closely on whether the molecules are chiral or achiral and on the stereochemistry of the ketal OMe groups. In achiral compounds, the most stable conformation of each compound has, in both the liquid and solid states, the two NH–CO links positioned perpendicular to the macrocycle plane, lending to the trans-7,7′–OMe macrocycles 6b and 7b a rectangular [3434]-type structure. In contrast, in chiral compounds, the most stable conformations are not the same in the liquid and solid phases. In the liquid state the conformations are set by the presence of one or two N4–HO1′, N4′–HO1 intramolecular hydrogen bonds that position the amide group parallel to the macrocycle plane, whereas in the solid state the amide moieties again adopt a perpendicular position which can be stabilized, when the 3-R substituent is not too bulky, by intermolecular N–HOC bonds between parallel sheets, and exceptionally, in the cis-7,7′-OMe-3,3′-Ph compound 1c, by a π–π stacking effect between the phenyl group
Protein sources alternative to meat: state of the art and involvement of fermentation
Meat represents an important protein source, even in developing countries, but its production is scarcely sustainable, and its excessive consumption poses health issues. An increasing number of Western consumers would replace, at least partially, meat with alternative protein sources. This review aims at: (i) depicting nutritional, functional, sensory traits, and critical issues of single-cell proteins (SCP), filamentous fungi, microalgae, vegetables (alone or mixed with milk), and insects and (ii) displaying how fermentation could improve their quality, to facilitate their use as food items/ingredients/supplements. Production of SCP (yeasts, filamentous fungi, microalgae) does not need arable land and potable water and can run continuously, also using wastes and byproducts. Some filamentous fungi are also consumed as edible mushrooms, and others are involved in the fermentation of traditional vegetable-based foods. Cereals, pseudocereals, and legumes may be combined to offer an almost complete amino acid profile. Fermentation of such vegetables, even in combination with milk-based products (e.g., tarhana), could increase nutrient concentrations, including essential amino acids, and improve sensory traits. Different insects could be used, as such or, to increase their acceptability, as ingredient of foods (e.g., pasta). However, insects as a protein source face with safety concerns, cultural constraints, and a lack of international regulatory framework.info:eu-repo/semantics/publishedVersio
Gene Capture Coupled to High-Throughput Sequencing as a Strategy for Targeted Metagenome Exploration
International audienceNext-generation sequencing (NGS) allows faster acquisition of metagenomic data, but complete exploration of complex ecosystems is hindered by the extraordinary diversity of microorganisms. To reduce the environmental complexity, we created an innovative solution hybrid selection (SHS) method that is combined with NGS to characterize large DNA fragments harbouring biomarkers of interest. The quality of enrichment was evaluated after fragments containing the methyl coenzyme M reductase subunit A gene (mcrA), the biomarker of methanogenesis, were captured from a Methanosarcina strain and a metagenomic sample from a meromictic lake. The methanogen diversity was compared with direct metagenome and mcrA-based amplicon pyrosequencing strategies. The SHS approach resulted in the capture of DNA fragments up to 2.5 kb with an enrichment efficiency between 41 and 100%, depending on the sample complexity. Compared with direct metagenome and amplicons sequencing, SHS detected broader mcrA diversity, and it allowed efficient sampling of the rare biosphere and unknown sequences. In contrast to amplicon-based strategies, SHS is less biased and GC independent, and it recovered complete biomarker sequences in addition to conserved regions. Because this method can also isolate the regions flanking the target sequences, it could facilitate operon reconstructions
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