1,002 research outputs found
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What do we know about succession in family businesses? Mapping current knowledge and unexplored territory
We review studies on succession in family businesses that have been done since Handler’s (1994) seminal literature review on the topic in an effort to synthesize existing research and outline paths for future studies. We offer three contributions. First, we select succession studies that adhere to established methodological standards. Second, we review these studies based on the perspective that succession is a process comprising five stages across three levels of analysis. Finally, we outline current gaps in our knowledge and ask researchers to adopt a more holistic approach when studying succession
Anti-deuterons from heavy Dark Matter
We study the fluxes of anti-deuterons that could be produced by annihilations
in the galactic halo of Dark Matter particles with multi-TeV mass and a large
annihilation cross section, as indicated by the recent PAMELA results. The
model of Minimal Dark Matter (MDM) is an example in this category. We find that
the fluxes are well within the reach of planned experiments for DM candidates
that annihilate mainly into quark pairs, and also extend into the multi-GeV
range above the background. They are instead suppressed and concentrated at too
large energies to emerge above the background if the main annihilation channel
is into gauge bosons (such as in particular W+W- in the MDM case).Comment: 17 pages, 6 figure
Gait Asymmetry in People With Parkinson’s Disease Is Linked to Reduced Integrity of Callosal Sensorimotor Regions
Background: Individuals with Parkinson’s disease (PD) often manifest significant temporal and spatial asymmetries of the lower extremities during gait, which significantly contribute to mobility impairments. While the neural mechanisms underlying mobility asymmetries within this population remain poorly understood, recent evidence points to altered microstructural integrity of white matter fiber tracts within the corpus callosum as potentially playing a substantial role.
Objectives: The purpose of this study was to quantify spatial and temporal gait asymmetries as well as transcallosal microstructural integrity of white matter fiber tracts connecting the primary and secondary sensorimotor cortices in people with PD and age-matched control participants.
Methods: Spatial and temporal gait asymmetry in the levodopa off state was assessed using an instrumented walkway. On the next day, diffusion-weighted images were collected to assess white matter microstructural integrity in transcallosal fibers connecting the homologous sensorimotor cortical regions.
Results: People with PD exhibited significantly more temporal and spatial gait asymmetry than healthy control subjects. Furthermore, people with PD had significantly reduced white matter microstructural integrity of transcallosal fibers connecting homologous regions of the pre-supplementary motor and supplementary motor areas (SMAs), but not the primary motor or somatosensory cortices. Finally, reduced transcallosal fiber tract integrity of the pre-SMA and S1 was associated with greater step length asymmetry in people with PD.
Conclusion: People with PD showed increased step length asymmetries and decreased microstructural integrity of callosal white matter tracts connecting the higher-order sensorimotor cortices (pre-SMA and SMA). The strong association between gait asymmetries and corpus collosum integrity, supports the hypothesis that reduced transcallosal structural connectivity is a significant mechanism underlying gait asymmetries in people with PD
Development and Performance of Power-Operated Garlic Bulb Breaker
A power-operated garlic bulb breaker to separate cloves from whole-garlic-bulbs was developed, its operational parameters optimized and its performance evaluated. The garlic bulb breaker consisted of a feeding chute, two-stage padded rubber rollers, a blower, outlets for cloves and skins, a main frame, power and power transmission system. The garlic bulb breaker was evaluated using three types of rubber padding material viz., plain type, button type and corrugated type, with four levels of clearance between rubber rollers viz., 15, 18, 21 and 24mm, three levels of peripheral speed, viz., 259.2, 302.4 and 345.6 m/min. The machine displayed performance parameters in terms of breaking efficiency at 96%, per cent clumps of cloves 1.22, per cent clove damage 1.7, per cent clove loss 1.08, and bulb-breaking capacity of 780kg/h using corrugated padding material fitted at 18mm clearance and 259.4m/min peripheral speed. Operating cost of the machine was Rs. 0.06/kg against Rs. 2.25/kg incurred with manual clove separation of cloves
Radiatively induced flavour violation in the general two-Higgs doublet model with Yukawa alignment
The most general two Higgs doublet model contains new sources of flavour
violation that are usually in conflict with the experimental constraints. One
possibility to suppress the exotic contribution to the flavour changing neutral
currents consists on imposing the alignment of the Yukawa couplings. This
condition presumably holds at a high-energy scale and is spoiled by the
radiative corrections. We compute in this letter the size of the radiatively
induced flavour violating Higgs couplings at the electroweak scale. These also
yield the absolute lower bound on the size of the exotic contributions to the
flavour changing neutral currents in any two Higgs doublet model, barring
cancellations and the existence of discrete symmetries. We show that these
contributions are well below the experimental bounds in large regions of the
parameter space.Comment: 15 pages, 2 figure
Synthesis of Mixed Ligand Complexes of M(II) Dithiocarbamato Derivative and 2,2'-bipyridyl and Study their Cytotoxic Effect Against HepG2 Cell Line in vitro
Mixed ligand of Co and Ni (II) complexes were prepared from [5-(p-nitrophenyl)-4/-phenyl-1,2,4-triazole-3-dithiocarbamato hydrazide](TRZ.DTC) as primary ligand and 2,2'-bipyridyl (bipy) as a co-ligand with metal salts. These complexes were analytically and spectroscopically characterized in solid state by elemental analyses, flame atomic absorption, magnetic susceptibility and molar conductance measurements, as well as by UV–Vis and FTIR spectroscopy. Infrared, ultra violet spectra reveal a bidentate coordination of the two ligands with metal ions 1:1:1 mole ratio. Room temperature magnetic moments and solid reflectance spectra data indicate paramagnetic complexes with five-coordinate square pyramidal geometry for nickel (II) complex, while six-coordinate octahedral geometry for cobalt (II) complex in solid state. The mixed ligand and its respective complexes were screened for cytotoxicity assay on human HepG2 cell line using cis-Pt drug as a control positive following the cell culture method for 3 days after treatment with the tested compounds using eight different concentrations. The bioassay results showed good inhibition activity of these synthetic compounds especially Ni (II) complex on selected cell lines comparable with standard drug
Freezing of gait associated with a corpus callosum lesion
Freezing of gait (FoG) is a debilitating feature of Parkinson’s disease and other parkinsonian disorders. This case demonstrates a variant of freezing of gait in a non-parkinsonian patient with a lesion of the anterior corpus callosum. The freezing improved with increased upper extremity sensory input, suggesting that compensatory circuits for use of somatosensory inputs from the arms to postural and locomotor centers were intact
Long-Term Cell Tracking Following Local Injection of Mesenchymal Stromal Cells in the Equine Model of Induced Tendon Disease.
Tendon disease has been treated with multipotent mesenchymal stromal cells (MSCs) in the equine large-animal model with promising success. The aim of this study was to gain more insight into the fate and biodistribution of MSCs after local application into tendon lesions by long-term cell tracking in this large-animal model. Superficial digital flexor tendon lesions were induced in all limbs in six horses and injected with 10 × 10 6 Molday ION Rhodamine B™-labeled MSCs suspended in serum or serum alone. Follow-up was performed using low-field magnetic resonance imaging (MRI), flow cytometry, and histology. Cell tracking based on the hypointense artifacts induced by the superparamagnetic iron oxide (SPIO) labeling agent in MRI as well as based on Rhodamine B fluorescence was feasible. However, Prussian blue staining for assessment of histology was not entirely specific for SPIO. Labeled cells could be traced at their injection site by MRI as well as histology for the whole follow-up period of 24 weeks. Although the numbers of labeled cells within the injected tendon lesions decreased over time, part of the applied cells appeared to remain viable and integrated within the injured tissue. Furthermore, small numbers of labeled cells were identified in peripheral blood within the first 24 h after cell injection and could also be found until week 24 within the contralateral control tendon lesions that had been injected with serum. The present findings unveil details on MSC biodistribution and persistence after their local application, which are of clinical relevance with regard to MSC safety and mechanisms of action
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