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This paper aims to estimate a supply response to monetary incentives to donate organs using a survey based on Adams, Barnett and Kaserman.

The paper uses bootstrap techniques to estimate the characteristics of individuals and their willingness to accept monetary compensation for an organ donation commitment. It uses the estimates to fuel a simulation that examines the relationship between a market‐clearing price and the usability rate. The usability rate is the proportion of deaths that result in tissues that are viable for transplant.

By analyzing the relationship between usability rate and market‐clearing price, the paper identifies three important ranges. When the usability rate is about 5 percent, a donation‐only system (zero price) should clear the market. At a usability rate between 2 and 5 percent, modest monetary incentives can attract a supply response that will clear the market. When the usability rate is less than 2 percent, supply becomes sufficiently inelastic so that even large monetary incentives will not solve the shortage problem.

If the market mechanism were capable of yielding a greater number of organs for transplantation than the current system, then its adoption would save numerous lives and significantly reduce the cost of treating a variety of serious diseases. Also, it is useful in a benefit‐cost analysis framework designed to measure the social value of refinements in the coordination system.

By relating the market‐clearing price of organs to their usability rates, this paper draws attention on the importance of interdisciplinary studies.

The debate over whether or not to allow the sale of human organs is compelling enough to warrant discussion. A literature review revealed much ethical discussion, but little discussion was found on economic outcomes related to donors and selling human organs. It was demonstrated in the literature how an increased organ supply will benefit recipients. If allowing the sale of organs is the way to increase the organ supply for the benefit of recipients, then, in order to demonstrate that donors will not be exploited, it must be demonstrated how, and if, such sales would benefit those donors. This study explores whether or not one should sell human organs. Using basic models, this study develops economic scenarios and outcomes related to the selling of human organs with particular focus on pricing and profitability in relation to donor benefit. Theoretical outcomes show that the donor will not benefit in the long run.

The purpose of this research is to correct the flawed analysis contained in a recent paper by Kolnsberg that appeared in this journal.

In her paper, Kolnsberg raises the extremely important question of whether we should allow the sale of human organs for transplantation. She concludes, mistakenly, that we should not allow such sales. The error that leads her to this incorrect conclusion is the application of a nonsensical criterion for determination of whether sales of a good should be allowed. Specifically, she argues that, if the suppliers of living donor organs will be unable to earn substantial economic profits in the long run, then such sales should be banned. This arbitrary (and erroneous) criterion ignores: the social welfare gains achievable through organ sales; the much greater promise offered by cadaveric donor payments; and the very real and tragic consequences of the current ban on such payments – over 6,000 lives lost unnecessarily each year in the US alone.

The principal finding of the corrected analysis is that, contrary to the conclusion reached by Kolnsberg, paying cadaveric organ donors would save both money and lives.

Given the compelling case for cadaveric donor payments, trials need to be conducted to reveal both the magnitude of compensation required to resolve the shortage and the most efficient payment mechanisms.

Given the historical failure of the current altruistic organ procurement policy, asserts that a revised system that incorporates organ donor payments is essential to a successful resolution of this shortage.

Bioprinting is a promising technology, which has gained a recent attention, for application in all aspects of human life and has specific advantages in different areas of medicines, especially in ophthalmology. The three-dimensional (3D) printing tools have been widely used in different applications, from surgical planning procedures to 3D models for certain highly delicate organs (such as: eye and heart). The purpose of this paper is to review the dedicated research efforts that so far have been made to highlight applications of 3D printing in the field of ophthalmology.

In this paper, the state-of-the-art review has been summarized for bioprinters, biomaterials and methodologies adopted to cure eye diseases. This paper starts with fundamental discussions and gradually leads toward the summary and future trends by covering almost all the research insights. For better understanding of the readers, various tables and figures have also been incorporated.

The usages of bioprinted surgical models have shown to be helpful in shortening the time of operation and decreasing the risk of donor, and hence, it could boost certain surgical effects. This demonstrates the wide use of bioprinting to design more precise biological research models for research in broader range of applications such as in generating blood vessels and cardiac tissue. Although bioprinting has not created a significant impact in ophthalmology, in recent times, these technologies could be helpful in treating several ocular disorders in the near future.

This review work emphasizes the understanding of 3D printing technologies, in the light of which these can be applied in ophthalmology to achieve successful treatment of eye diseases.

The purpose of this paper is to present a surgical robot for spinal fusion and its control framework that provides higher operation accuracy, greater flexibility of robot position control, and improved ergonomics.

A human‐guided robot for the spinal fusion surgery has been developed with a dexterous end‐effector that is capable of high‐speed drilling for cortical layer gimleting and tele‐operated insertion of screws into the vertebrae. The end‐effector is position‐controlled by a five degrees‐of‐freedom robot body that has a kinematically closed structure to withstand strong reaction force occurring in the surgery. The robot also allows the surgeon to control cooperatively the position and orientation of the end‐effector in order to provide maximum flexibility in exploiting his or her expertise. Also incorporated for improved safety is a “drill‐by‐wire” mechanism wherein a screw is tele‐drilled by the surgeon in a mechanically decoupled master/slave system. Finally, a torque‐rendering algorithm that adds synthetic open‐loop high‐frequency components on feedback torque increases the realism of tele‐drilling in the screw‐by‐wire mechanism.

Experimental results indicated that this assistive robot for spinal fusion performs drilling tasks within the static regulation errors less than 0.1 μm for position control and less than 0.05° for orientation control. The users of the tele‐drilling reported subjectively that they experienced torque feedback similar to that of direct screw insertion.

Although the robotic surgery system itself has been developed, integration with surgery planning and tracking systems is ongoing. Thus, the screw insertion accuracy of a whole surgery system with the assistive robot is to be investigated in the near future.

The paper arguably pioneers the dexterous end‐effector appropriately designed for spinal fusion, the cooperative robot position‐control algorithm, the screw‐by‐wire mechanism for indirect screw insertion, and the torque‐rendering algorithm for more realistic torque feedback. In particular, the system has the potential of circumventing the screw‐loosening problem, a common defect in the conventional surgeon‐operated or robot‐assisted spinal fusion surgery.

The purpose of this paper is to prepare alginate‐pectin‐starch containing matrices expanded by the generation of carbon dioxide, from carbonates when in contact with acids, characterise their structure in vitro and to assess their capacity to provide satiety in vivo.

For in vitro characterisation, carbon dioxide expanded polysaccharide matrices (rafts) were prepared in HCl and their structural strength was measured in terms of their capacity to resist breakage in a model test system. For in vivo trials, 12 healthy volunteers (mixed sex, aged 25‐55) were recruited to take part in the three‐part trial. Each part lasted for one week where volunteers consumed polysaccharides (in 50 ml water) with or without rafting salts (carbonates), or water (as a control). Effects on satiety, reduction of food intake and any change to body weight were evaluated with the volunteers.

The in vitro results showed that aqueous solution/dispersions (50 ml) of alginate‐pectin‐starch matrices produced rafts in hydrochloric acid (pH < 2), where increasing the ratio of carbonates to polysaccharides (range from 0.25:1 to 1.5:1, w/w) provided increased floatation capability but reducing gel strength. These rafts were stable for over 24 h at room temperature within 0.05‐0.5 M HCl. For in vivo “satiety” studies, when volunteers consumed (daily) aliquots of the polysaccharide mixture plus flavour and sweetener without carbonates 2.5 h after lunch, they felt the onset of hunger on average 186 ± 68 min after consumption of the polysaccharides. This was not significantly different from a water only control (onset of hunger at 165 ± 47 min). When polysaccharides plus flavour sweetener and carbonates were consumed, however, volunteers reported feeling the onset of hunger at 224 ± 62 min on average after consumption which was significantly different from the water control (p < 0.001), or the polysaccharides without carbonates (p < 0.01). When consuming the polysaccharide rafting format, half of the volunteers reported a reduction in size of their evening meal.

These data indicate that the alginate‐pectin‐starch combination with carbonate salts in a “gastric rafting format” provide a potential approach in the management of body weight and obesity.

The paper is targeted to health service management teams as an aid to understanding the relationship between investment in process redesign in a clinical laboratory environment and improved quality of service/increased clinical activity.

An audit of the unit's serum screening capability was performed against the standards of the current UK allocation scheme for cadaveric kidneys. Based on findings of this audit the laboratory's serum screening protocol was redesigned involving development of a new testing strategy and introduction of novel methods. A concurrent review of the effects of this initiative in terms of cadaveric kidney offers received/transplant numbers was undertaken and a cost‐benefit analysis made.

An improved eligibility of the patient cohort for cadaveric kidney offers was obtained together with a reduced unexpected positive crossmatch rate. These factors have together contributed to an increase in transplant numbers at the centre. Significant cost benefits have been achieved

The relevance of the findings relating to patient eligibility for available cadaveric grafts is limited to organ‐sharing schemes in which recipient sensitisation is considered as part of the allocation process.

The experience reported demonstrates the necessity of assessing the clinical impact of changes in practice when judgements are being made regarding the costs of laboratory services. In this respect the paper is the first from within this discipline to make this association.

The paper presents an hybrid optimization technique which couples the artificial immune system (AIS) algorithm with a zeroth order deterministic method.

AIS has been developed to tackle multi‐modal optimization problems and it has shown a great ability to explore the objective function space. The algorithm is subdivided into two phases: an outer and an inner cycle. The outer cycle is devoted to the exploration of the space while the inner is a local exploration of the objective function. The new hybrid method proposes to replace the local search by a zeroth order deterministic search to speed up the overall convergence.

Results on two multi‐modal analytical objective functions show an increase of speed of the new procedure with respect to the standard AIS. The method is also tested on the TEAM 22 numerical problem and some a posteriori techniques for the analysis of multimodal blind objective functions are discussed.

The new Multimodal optimization algorithm has allowed to explore thoroughly feasibility space giving rise to a partition of the whole space, the use of hybrid technique increases the performances of standard AIS increasing the convergence to the optimal points.

To introduce recent research and development of biopolymer deposition for freeform fabrication of three‐dimensional tissue scaffolds that is capable of depositing bioactive ingredients.

A multi‐nozzle biopolymer deposition system is developed, which is capable of extruding biopolymer solutions and living cells for freeform construction of 3D tissue scaffolds. The deposition process is biocompatible and occurs at room temperature and low pressures to reduce damage to cells. In contrast with other systems, this system is capable of, simultaneously with scaffold construction, depositing controlled amount of cells, growth factors, or other bioactive compounds with precise spatial position to form complex cell‐seeded tissue constructs. The examples shown are based on sodium alginate solutions and poly‐ε‐caprolactone (PCL). Studies of the biopolymer deposition feasibility, structural formability, and different material deposition through a multi‐nozzle heterogeneous system are conducted and presented.

Provides information about the biopolymer deposition using different nozzle systems, the relations of process parameters on deposition flow rate and scaffold structural formability. Three‐dimensional alginate‐based scaffolds and scaffold embedded with living cells can be freeform constructed according to various design configurations at room temperature without using toxic materials.

Other biopolymers may also be studied for structure formation. Studying cell viability and cellular tissue engineering behavior of the scaffolds after the cell deposition should be further investigated.

A very useful and effective tool for construction of bioactive scaffolds for tissue engineering applications based on a multi‐nozzle biopolymer deposition.

This paper describes a novel process and manufacturing system for fabrication of bioactive tissue scaffolds, automatic cell loading, and heterogeneous tissue constructs for emerging regenerative medicine.

The purpose of this paper is to evaluate the effect of fasting on anthropometry and body composition in fasting obese and non‐obese subjects.

In total, 25 volunteers (male and female) were recruited during Ramadan. Age, sex, weight, height, waist and hip circumference and menstrual cycle status (in case of females) were recorded on day 1, and on day 21 weight and waist and hip circumference were also recorded. Similarly, bioelectrical impedance analysis (BIA) was performed on days 1 and 21 for the assessment of changes in body composition. From weight and height, basal metabolic Index (BMI) was determined. Waist‐hip ratio was determined from the waist and hip circumferences.

Weight was significantly (p<0.001) reduced in obese individuals on day 21 and accompanied by significant (p<0.01) reduction in waist hip ratios. BIA showed no significant change in the intra or extra cellular water. However, there has been shift of water between the two compartments and there was a strong positive correlation (r=0.9) between the fat free mass and total body water and negative association (r=−0.9) with total body water.

This study indicates that fasting could be a useful tool for the management of body weight without having a major shift in the body composition.