Summary:
[Short description of the paper. In two or three phrases describe the problem that was addressed by the authors and the approach they took to solve it.]

Hypothesis:
[If Applicable: Describe the assumptions that the authors have made and they hypothesis of their work, note that not all papers will fit the model of hypothesis driven work, for example, the description of an image database, or the description of a toolkit will not be driven by an hypothesis, in which case, please simply write : “Non Applicable” in this field or delete the subtitle.]

Evidence:
[Describe the evidence that the authors provide in order to support their claims in the paper. This is a key component on Open Science, opinions that are not supported by evidence should be labeled as “speculations” or “author’s opinion” while. The same rule applies to the text of the reviews: claims should be supported by evidence]

Open Science:
[Describe how much the paper and its addendums adhere to the concept of Open Science. Do the authors provide the source code of the programs used in their experiments? Do the authors provide the input images that they used? Or are those images publicly available? Do the authors provide the output images that they show in the paper? Do the authors provide enough details for you to be able to replicate their work?]

Reproducibility:
[Did you reproduce the authors’ work?
Did you download their code? Did you compile it? Did you run it?
Did you managed to get the same results that they reported?
Were there information missing from the paper, that was necessary for you to reproduce the work? Suggest improvements that will make easier for future readers to reproduce this work.]

Use of Open Source Software:
[Did the authors use Open Source software in their work? Do they describe their experience with it, advantages and disadvantages? Do they provide advice for future users of those Open Source packages?]

Open Source Contributions:
[Do the author’s provide their source code? Is it in a form that is usable? Do they describe clearly how to use of the code? How long did it take you to use that code?]

Code Quality:
[If the authors provided their source code: Was the code easy to read? Did they use a modern coding style? Did they rely on non-portable mechanism? Was it suitable for multiple-platforms?]

Applicability to other problems:
[Do you find that the authors methods can be applied to other image analysis problems? Suggest other disciplines or even other specific projects that could take advantage of this work]

Suggestions for future work:
[Suggest to authors future directions for improving their methods, or other domains from which they could learn technique that could help them advance in their research.]

Requests for additional information from authors:
[Did you find that information was missing from the paper? Maybe parameters for running the tests? Maybe some images were missing? Would you like to get more details on how the diagrams, or plots were generated?]

Additional Comments:
[This is a free-form field]

Summary:
This paper describes a fluid simulation method for smoke and blood simulation in surgery training applications. The main focus is not accuracy, since the computational cost is too high to keep up real-time performance while also handling the soft tissue simulation, collision detection and haptic feedback. Therefore, this work focuses on a very simple uncoupled particle based model to enhance the visual experience.

Hypothesis:
The hypothesis is that even a simple blood/smoke simulation will contribute to the realism of the surgery simulation environment.

Evidence:
Some screenshots are provided to illustrate the results of the simulation. No specific evidence is provided demonstrating that this highly simplified blood/smoke simulation is indeed enhancing the simulation enough to be worth the extra computational work.

Open Science:
This work is based on the open source SPRING package and the source code is available.

Applicability to other problems:
Using uncoupled particles to simulate fluid motion can be applied to other problems where speed is more important than accuracy. However, it would be more useful if the authors work describing their technique in some more detail.

Suggestions for future work:
I think a discussion of the numbers provided in the results section, and a comparison with other existing methods would greatly contribute to the usefulness of this paper.

Requests for additional information from authors:
Some videos could be more useful for demonstrating the visual results of the fluid simulation, rather than just still images. Also, the underlying physical model and simplifications could be explained in some more detail to provide better insight and to enable the users to extend this work.

Additional Comments:
Minor typos in the text.

Summary:
The authors describe the feature of visualising smoke and bleeding in a surgical simulation system using an uncoupled particle system.

Hypothesis:
Non applicable

Evidence:
Two color illustrations are provided to show that the described method woeks.

Open Science:
The paper is based on the open surgical simulator SPRING. The source code is available for download.

Reproducibility:
I was not able to compile the code. After inserting several missing class declaration, the compilation stopped due to a bug in the build system (Missing Makefile.src). I would suggest using a more configurable build system like autotools, cmake or scons.

Use of Open Source Software:
The software is build on several opensource libraries, including GLUT.

Open Source Contributions:
The authors do provide the source code. This is a fairly large software project and no attempt was done to understand the code.

Code Quality:
The code appears to be well written in C++. The authods claims that it can be built on multiple platforms, although I was not able to build it on Linux.

Applicability to other problems:
The problem that was addressed was smoke and bleeding simulation. The solution seems to be limited to this problem. The SPRING simulator can be used for many surgical tasks however.

Suggestions for future work:
Validation of the realism of the model should be performed.

Requests for additional information from authors:
More details would be of interest regarding the described simulation. The authors referes to Newtons second law, and gives a brief description of how the force is determined.

Additional Comments:
This is a very short description of some novel work in smoke and booold simulation. The method seems to be well suited for real-time computation. The meaning of the numbers given in the conclusion (this should be given in the result section) is not clear. How does this scale with respect to the tissue model and amount of smoke/blood? What kind of hardware was used in the experiement? A discussion is missing.

Summary:
This paper presents the implementation of smoke and bleeding algorithms for surgical simulation under SPRING. Their method use simple models to allow
real-time simulations.
Hypothesis:
Authors model fluids using a particle systems. They use an uncoupled particle system that follows the Newton\'s second law. The gradient of a potential function
yields the force.
Evidence:
Non Applicable
Open Science:
The authors work under the Open Source Spring (licensed GPL). This is a sourceforge project and the authors provide enough details to be able to replicate their work.
To compile SPRING I\'ve found some problems compiling under linux, but I have been able to resolve it. VC++ compiler supports some declarations that gcc cannot understand.
Reproducibility:
I have downloaded the Spring software, I have compiled and run it under linux. However I haven\'t been able to compile the source code attached to this paper, because I\'m trying under
linux and my system does\'nt find \"windows.h\" file (microsoft windows header file), so I have to hack my system first or compile under VC++.
Perhaps, it would be good if the authors included the .dll libraries in the attached file, or they try to compile their code using MinGW on Windows (this will eliminate any non-standard code that GCC doesn't understand).
However, the paper\'s figures are nice.
Use of Open Source Software:
The authors have developed under the Spring package: an open source software for surgical simulation.
Open Source Contributions:
The code proposed by the authors are developed under VC++ and I haven't been able to run/try it under linux yet. I have to hack my system first. The code is included in an open
source project, and it could be used for everyone. This is a very interesting contribution for Open Source Community.
Code Quality:
The code is easy to read, and it should be suitable for multiple-platforms. However, this contribution is done under VC++ and Windows. I haven't been able to compile it yet, I am working in it
to eliminate any non-standard code that GCC doesn't understand.
Applicability to other problems:
Non applicable.
Suggestions for future work:
I have no comments, it is a good work, and this group has experience in this research. Perhaps, it would be interesting to improve the building process of the package.
Requests for additional information from authors:
I have found some typos in the text. A conclusions section would be good.
Additional Comments:
My rating is based on IJ reviewer guidelines