Influence Costs in Agribusiness Cooperatives: Evidence from Case Studies

This article addresses the influence costs problem in the governance structure ‘agribusiness cooperative.’ Influence costs are higher in cooperatives than in investor-oriented firms due to the unique governance structure of the former. Hypotheses are formulated and tested regarding the relationship between influence costs and seven variables: membership size, member heterogeneity, average member age, singleness of purpose, managerial power over members, level of managerial compensation, and professional versus inside management. The main results are that heterogeneous member preferences, older average member age, and investment in multiple product lines all contribute to higher influence costs. At the same time, cooperatives with well-paid, powerful and professional managers incur lower influence costs. The impact of membership size on the level of influence costs is undetermined

A descriptive analysis of the effect of the national COVID-19 lockdown on the workload and case mix of patients presenting to a district-level emergency centre in Cape Town, South Africa

Background. The global COVID-19 pandemic caused many countries to institute nationwide lockdowns to limit the spread of the disease.Objectives. To describe the effect of the national COVID-19 lockdown in South Africa (SA) on the workload and case mix of patients presenting to a district-level emergency centre.Methods. The electronic patient tracking and registration database at Mitchells Plain Hospital, a district-level hospital in Cape Town, was retrospectively analysed. The 5-week lockdown period (27 March - 30 April 2020) was compared with a similar period immediately before the lockdown (21 February - 26 March). A comparison was also made with corresponding time periods during 2018 and 2019. Patient demographics, characteristics, diagnoses and disposition, as well as process times, were compared.Results. A total of 26 164 emergency centre visits were analysed (8 297 in 2020, 9 726 in 2019, 8 141 in 2018). There was a reduction of 15% in overall emergency centre visits from 2019 to 2020 (non-trauma 14%, trauma 20%). A 35% decrease was seen between the 2020 lockdown period and the 5-week period before lockdown (non-trauma 33%, trauma 43%), and the reduced number of visits stayed similar throughout the lockdown period. The median age increased by 5 years during the 2020 lockdown period, along with an 8% decrease in patients aged <12 years. High-acuity patients increased by 6% and the emergency centre mortality rate increased by 1%. All process times were shorter during the lockdown period (time to triage –24%, time to consultation –56%, time to disposition decision –29%, time in the emergency centre –20%).Conclusions. The SA national COVID-19 lockdown resulted in a substantial decrease in the number of patients presenting to the emergency centre. It is yet to be seen how quickly emergency centre volumes will recover as lockdown measures are eased

Magnetic resonance angiography of collateral compensation in asymptomatic and symptomatic internal carotid artery stenosis

AbstractObjective: In patients with stenosis of the internal carotid artery (ICA), the presence of collateral circulatory pathways may be crucial to maintain cerebral perfusion pressure, metabolism, and function. The purpose of the present study was to determine whether patients with asymptomatic stenosis of the ICA have a better collateral ability of the circle of Willis when compared with patients with symptomatic ICA stenosis. Method: Magnetic resonance angiography consisting of the circle of Willis was performed in 19 patients with severe asymptomatic ICA stenosis and in 21 patients with severe symptomatic ICA stenosis prior to carotid endarterectomy and in 53 control subjects. Between group comparisons were made for function (directional flow) and anatomy (diameter). Results: In patients with asymptomatic ICA stenosis, the prevalence of collateral flow via the anterior communicating artery was significantly increased (37%, 7 of 19) compared with symptomatic patients (10%, 2 of 21) and control subjects (0%; P < .001). Patients with asymptomatic ICA stenosis demonstrated the largest mean diameter of the anterior communicating artery (1.33 ± 0.18 mm) compared with patients with symptomatic ICA stenosis (1.22 ± 0.18 mm) and control subjects (1.06 ± 0.10 mm, P < .05). No differences in collateral flow pattern or diameter were found for the posterior communicating artery between the groups. Conclusions: The present cross-sectional study demonstrates the importance of an adequate hemodynamic compensation via the circle of Willis in patients with ICA stenosis. Whether differences in collateral compensation can be used to select patients for CEA has yet to be determined. (J Vasc Surg 2002;36:799-805.

How Virtual Agents Can Learn to Synchronize: an Adaptive Joint Decision-Making Model of Psychotherapy

Joint decision-making can be seen as the synchronization of actions and emotions, usually via nonverbal interaction between people while they show empathy. The aim of the current paper was (1) to develop an adaptive computational model for the type of synchrony that can occur in joint decision-making for two persons modeled as agents, and (2) to visualize the two persons by avatars as virtual agents during their decision-making. How to model joint decision-making computationally while taking into account adaptivity is rarely addressed, although such models based on psychological literature have a lot of future applications like online coaching and therapeutics. We used an adaptive network-oriented modelling approach to build an adaptive joint decision-making model in an agent-based manner and simulated multiple scenarios of such joint decision-making processes using a dedicated software environment that was implemented in MATLAB. Programming in the Unity 3D engine was done to virtualize this process as nonverbal interaction between virtual agents, their internal and external states, and the scenario. Although our adaptive joint decision model has general application areas, we have selected a therapeutic session as example scenario to visualize and interpret the example simulations

Benefits of a marketing cooperative in transition agriculture: Mórakert purchasing and service co-operative

The paper analyses the potential benefits of marketing cooperatives in Hungary, employing a transaction cost economics framework. We found that the purchased quantity, the existence of contracts, flexibility and trust are the most important factors farmers consider when selling their products via a cooperative. The most striking result is that diversification has positive influences on the share of cooperatives in farmers’ sale. Furthermore, farmers with larger bargaining power have less willingness to sell their product to the cooperative. Surprisingly, asset specificity has rather negative effects on the share of cooperatives in members’ sales

Cyclic GMP in the pig vitreous and retina after experimental retinal detachment

Purpose: Earlier studies have revealed a decreased level of cGMP in vitreous fluid obtained from patients with a retinal detachment. To further investigate this phenomenon, we developed an experimental retinal detachment model in pigs. Methods: Experimental unilateral retinal detachments were induced in pig eyes by subretinal injection of 0.25% sodium hyaluronate. Fourteen days later the vitreous and retinas were analyzed for cGMP expression. Following enucleation, the retinas were incubated in the presence of a nonselective phosphodiesterase inhibitor (IBMX), and the particulate guanylyl cyclase stimulator atrial natriuretic peptide (ANP) or the soluble guanylyl cyclase stimulator sodium nitroprusside (SNP). cGMP was visualized in retinal wholemounts by immunochemistry combined with a computer based stereology system. cGMP levels in vitreous were determined by ELISA. Results: The mean vitreous cGMP level in pig eyes with a retinal detachment (1.45 pmol/ml) was significantly lower compared to the mean level of cGMP in healthy pig eyes (4.61 pmol/ml; p= 0.028 was considered significant). In the inner retina, ANP as well as SNP induced cGMP immunoreactivity in both detached and healthy retinas. After incubation with ANP, cGMP could also be detected in the outer nuclear layer of the detached retina, whereas this was not the case in the normal retina. Conclusions: Experimental retinal detachment in the pig eye leads to a decrease of cGMP levels in vitreous similar to that observed in clinical studies. This model may be helpful to analyze the mechanisms involved in cGMP dynamics following retinal detachment

Recommended implementation of arterial spin‐labeled perfusion MRI for clinical applications: A consensus of the ISMRM perfusion study group and the European consortium for ASL in dementia

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/109790/1/mrm25197.pd

99mTc-sestamibi is a substrate for P-glycoprotein and the multidrug resistance-associated protein.

99mTc-sestamibi (99mTc-MIBI) is a substrate for the P-glycoprotein (P-gp) pump but it is not known whether it is a substrate for the multidrug resistance-associated protein (MRP) pump. Therefore, 99mTc-MIBI was evaluated in the GLC4 cell line and its doxorubicin-resistant MRP-, but not P-gp-, overexpressing GLC4/ADR sublines as well as in the S1 cell line and its MRP-transfected subline S1-MRP. 99mTc-MIBI concentration decreased in the GLC4/ADR sublines with increasing MRP overexpression and was lower in S1-MRP than in S1. 99mTc-MIBI plus vincristine increased 99mTc-MIBI concentration in GLC4 lines compared with 99mTc-MIBI alone. 99mTc-MIBI efflux raised with increasing MRP expression in the GLC4 lines. Glutathione depletion elevated 99mTc-MIBI concentration in GLC4/ADR150x. Cross resistance for 99Tc-MIBI, used to test cytotoxicity of the Tc compound, was observed in GLC4/ADR150x vs GLC4. 99Tc-MIBI induced a synergistic effect on vincristine cytotoxicity in GLC4/ADR150x. These results show that 99mTc-MIBI is involved in MRP-mediated efflux. The fact that 99mTc-MIBI efflux is influenced by MDR1 and MRP expression must be taken into account when this gamma-rays-emitting complex is tested for tumour efflux measurements

No evidence for changes in GABA concentration, functional connectivity, or working memory following continuous theta burst stimulation over dorsolateral prefrontal cortex

Continuous theta burst stimulation (cTBS) is thought to reduce cortical excitability and modulate functional connectivity, possibly by altering cortical inhibition at the site of stimulation. However, most evidence comes from the motor cortex and it remains unclear whether similar effects occur following stimulation over other brain regions. We assessed whether cTBS over left dorsolateral prefrontal cortex altered gamma aminobutyric acid (GABA) concentration, functional connectivity and brain dynamics at rest, and brain activation and memory performance during a working memory task. Seventeen healthy individuals participated in a randomised, sham-controlled, cross-over experiment. Before and after either real or sham cTBS, magnetic resonance spectroscopy was obtained at rest to measure GABA concentrations. Functional magnetic resonance imaging (fMRI) was also recorded at rest and during an n-back working memory task to measure functional connectivity, regional brain activity (low-frequency fluctuations), and task-related patterns of brain activity. We could not find evidence for changes in GABA concentration (P = 0.66, Bayes factor [BF10] = 0.07), resting-state functional connectivity (P(FWE) > 0.05), resting-state low-frequency fluctuations (P = 0.88, BF10 = 0.04), blood-oxygen level dependent activity during the n-back task (P(FWE) > 0.05), or working memory performance (P = 0.13, BF10 = 0.05) following real or sham cTBS. Our findings add to a growing body of literature suggesting the effects of cTBS are highly variable between individuals and question the notion that cTBS is a universal ‘inhibitory’ paradigm