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1.
J Cancer Res Clin Oncol ; 148(1): 237-243, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34110490

ABSTRACT

BACKGROUND: The purpose of this study was to investigate the potential of a combination of 3D mixed-reality visualization of medical images using CarnaLife Holo (MedApp, Poland) system as a supporting tool for innovative, minimally invasive surgery/irreversible electroporation-IRA, Nano-Knife), microwave ablation (MWA)/for advanced gastrointestinal tumors. Eight liver and pancreatic tumor treatments were performed. In all of the patients undergoing laparoscopy or open surgery volume and margin were estimated by preoperative visualization. In all patients, neoplastic lesions were considered unresectable by standard methods. METHODS: Preoperative CT or MRI were transformed into holograms and displayed thanks to the HoloLens 2. During operation, the surgeon's field of view was augmented with a 3D model of the patient's relevant structures. RESULTS: The intraoperative hologram contributed to better presentation of tumor size and locations, more precise setting of needles used to irreversible electroporation and for determining ablation line in case of liver metastases. Surgeons could easily compare the real patient's anatomy to holographic visualization just before the operations. CONCLUSIONS: The combination of 3D mixed-reality visualization using CarnaLife Holo with IRA, MWA and next systemic treatment (chemotherapy) might be a new way in personalized treatment of advanced cancers.


Subject(s)
Electroporation/methods , Gastrointestinal Neoplasms/surgery , Imaging, Three-Dimensional/methods , Liver Neoplasms/surgery , Pancreatic Neoplasms/surgery , Radiofrequency Ablation/methods , Adult , Aged , Female , Holography , Humans , Laparoscopy , Male , Middle Aged , Minimally Invasive Surgical Procedures/methods , Precision Medicine/methods , Surgery, Computer-Assisted/methods
2.
Phys Chem Chem Phys ; 21(43): 23865-23879, 2019 Nov 07.
Article in English | MEDLINE | ID: mdl-31647077

ABSTRACT

Alchemical derivatives have been used in recent years to obtain essentially qualitative information about transformations in which the number of electrons is unchanged. Within the context of Conceptual DFT, we present a systematic approach for combining changes in both the number of electrons and the nuclear charge so that for example one can navigate from one neutral atom to another. A general formalism is presented for transformations involving changes both in or , where Parr's parabolic approach for the dependence is considered as one particular case and the ensemble description in the 0 K limit as the second case. The B3LYP functional in its CAMB3LYP version combined with the aug-cc-pCVQZ basis has been chosen to perform Coupled Perturbed Kohn Sham calculations of the alchemical derivatives. The monotonic behaviour of the alchemical potential is scrutinised. The order of magnitude analysis of the derivatives preludes convergence at third order. These results are injected in two strategies for obtaining transmutation energies from neutral atoms to a neighbouring neutral atom: one road moving along the diagonal, the other one walking along a pure alchemical road after ionisation or electron attachment. Roads involving the anion of the reference atom are much less successful than those involving its cation. The transmutation energy for the cationic pathway displays chemical accuracy when the procedure is carried at third order in . The difficulties inherent to an accurate description of the anion and its response functions are responsible for the shortcomings along the anionic paths. As a direct application Ionization Energies (IE) and Electron Affinities (EA) are evaluated showing an almost perfect agreement with the direct evaluation and a difference with experimental values less than 0.5 eV for the IE. For the first EA reasonable agreement is obtained with direct and experimental values whereas the second EAs for atoms with stable mono-anions show a remarkable agreement with literature data. Besides proof of concept that with the information content of an atom one can get accurate energetics of its neighbours, the results indicate that alchemical derivatives are capable to yield quantitative information when navigating through Chemical Compound Space.

3.
J Chem Theory Comput ; 14(2): 1154-1168, 2018 Feb 13.
Article in English | MEDLINE | ID: mdl-29300479

ABSTRACT

With the idea of using alchemical derivatives to explore in an efficient, computer- and cost-effective way Chemical Space was launched several years ago. In the context of Conceptual DFT response functions, these energies vs nuclear charge derivatives permit the estimatation of the energy of transmutants of a given starting or reference molecule showing different nuclear compositions. After an explorative study on small and planar molecules ( Balawender et al. J. Chem. Theory Comput. 2013 , 9 , 5327 ) by the present authors of this paper, the present study fully exploits the computational advantages of the alchemical derivatives in larger three-dimensional systems. Starting from a single reference calculation on C60, the complete BN substitution pattern, from single substituted C58BN via the belt (C20(BN)20 and the ball C12(BN)24 structures to the fully substituted (BN)30, is explored. Successive and simultaneous substitution strategies are followed and compared, indicating that both techniques yield identical results up to 13 substitutions but that for higher substitutions the simultaneous approach needs to be taken. Due to the cost-efficiency of the algorithm this path can indeed be followed as opposed to earlier work in the literature where for each step a full SCF calculation was at stake leading to prohibitively large computational demands for adopting the simultaneous approach. Previously formulated rules governing the substitution pattern by Kar and co-workers are scrutinized in this context and reformulated giving chemical insight in the gradual substitution process and the relative energies of the isomers. In its present form the method offers an interesting venue to study BN substitution patterns in higher fullerenes and graphene and in general paves the way for more efficient exploration of the Chemical Space.

4.
J Chem Phys ; 142(5): 054104, 2015 Feb 07.
Article in English | MEDLINE | ID: mdl-25662633

ABSTRACT

The chemical reactivity indices as the equilibrium state-function derivatives are revisited. They are obtained in terms of the central moments (fluctuation formulas). To analyze the role of the chemical hardness introduced by Pearson [J. Am. Chem. Soc. 105, 7512 (1983)], the relations between the derivatives up to the third-order and the central moments are obtained. As shown, the chemical hardness and the chemical potential are really the principal indices of the chemical reactivity theory. It is clear from the results presented here that the chemical hardness is not the derivative of the Mulliken chemical potential (this means also not the second derivative of the energy at zero-temperature limit). The conventional quadratic dependence of energy, observed at finite temperature, reduces to linear dependence on the electron number at zero-temperature limit. The chemical hardness plays a double role in the admixture of ionic states to the reference neutral state energy: it determines the amplitude of the admixture and regulates the damping of its thermal factor.

5.
Phys Chem Chem Phys ; 16(28): 14928-46, 2014 Jul 28.
Article in English | MEDLINE | ID: mdl-24931447

ABSTRACT

The analysis of the information and complexity measures as tools for the investigation of the chemical reactivity has been done in the spin-position and the position spaces, for the density and shape representations. The concept of the transferability and additivity of atoms or functional groups were used as "checkpoints" in the analysis of obtained results. The shape function as an argument of various measures reveals less information than the spinor density. Use of the shape function can yield wrong conclusions when the information measures such as the Shannon entropy (SE, S), the Fisher information (FI, I), the Onicescu information (OI, D), and complexities based on them are used for the systems with different electron numbers. Results obtained in the spinor-density representation show the transferability and additivity (while lacking in the case of the shape representation). The group transferability is well illustrated in the example of the X-Y molecules and their benzene derivatives. Another example is the methyl group transferability presented on the alkane-alkene-alkyne set. Analysis of the results displayed on planes between the three information-theoretical (IT) based measures has shown that the S-I plane provides "richer" information about the pattern, organization, similarity of used molecules than the I-D and D-S planes. The linear relation of high accuracy is noted between the kinetic energy and the FI and the OI measures. Another interesting regression was found between the atomization total energy and the atomization entropy. Unfortunately, the lack of the group electronic energy transferability indicates that no general relations between the IT measures and the chemical reactivity indices are observed. The molecular set chosen for the study includes different types of molecules with various functional groups (19 groups). The used set is large enough (more than 700 molecules) and diverse to improve the previous understating of molecular complexities and to generalize obtained conclusions.


Subject(s)
Alkanes/chemistry , Alkenes/chemistry , Alkynes/chemistry , Benzene Derivatives/chemistry , Quantum Theory , Entropy
6.
Dalton Trans ; 43(8): 3048-51, 2014 Feb 28.
Article in English | MEDLINE | ID: mdl-24281820

ABSTRACT

An efficient synthetic procedure for obtaining manganese carboxylates including a trinuclear cluster [Mn3(PhCO2)6(THF)4]2 and a unique [Mn(PhCO2)2]n chiral 3D network is reported. The procedure involves a simple redox process, in which acidic protons are reduced to gaseous hydrogen by oxidizing metallic manganese under solvothermal conditions.


Subject(s)
Carboxylic Acids/chemistry , Coordination Complexes/chemical synthesis , Manganese/chemistry , Coordination Complexes/chemistry , Crystallography, X-Ray , Hydrogen/chemistry , Molecular Conformation , Oxidation-Reduction , Stereoisomerism
7.
J Chem Theory Comput ; 9(12): 5327-40, 2013 Dec 10.
Article in English | MEDLINE | ID: mdl-26592270

ABSTRACT

In this paper, we verify the usefulness of the alchemical derivatives in the prediction of chemical properties. We concentrate on the stability of the transmutation products, where the term "transmutation" means the change of the nuclear charge at an atomic site at constant number of electrons. As illustrative transmutations showing the potential of the method in exploring chemical space, we present some examples of increasing complexity starting with the deprotonation, continuing with the transmutation of the nitrogen molecule, and ending with the substitution of isoelectronic B-N units for C-C units and N units for C-H units in carbocyclic systems. The basis set influence on the qualitative and quantitative accuracies of the alchemical predictions was investigated. The alchemical deprotonation energy (from the second order Taylor expansion) correlates well with the vertical deprotonation energy and can be used as a preliminary indicator for the experimental deprotonation energy. The results of calculations for the BN derivatives of benzene and pyrene show that this method has great potential for efficient and accurate scanning of chemical space.

8.
J Chem Phys ; 136(3): 034104, 2012 Jan 21.
Article in English | MEDLINE | ID: mdl-22280741

ABSTRACT

We present an analytical approach to treat higher order derivatives of Hartree-Fock (HF) and Kohn-Sham (KS) density functional theory energy in the Born-Oppenheimer approximation with respect to the nuclear charge distribution (so-called alchemical derivatives). Modified coupled perturbed self-consistent field theory is used to calculate molecular systems response to the applied perturbation. Working equations for the second and the third derivatives of HF/KS energy are derived. Similarly, analytical forms of the first and second derivatives of orbital energies are reported. The second derivative of Kohn-Sham energy and up to the third derivative of Hartree-Fock energy with respect to the nuclear charge distribution were calculated. Some issues of practical calculations, in particular the dependence of the basis set and Becke weighting functions on the perturbation, are considered. For selected series of isoelectronic molecules values of available alchemical derivatives were computed and Taylor series expansion was used to predict energies of the "surrounding" molecules. Predicted values of energies are in unexpectedly good agreement with the ones computed using HF/KS methods. Presented method allows one to predict orbital energies with the error less than 1% or even smaller for valence orbitals.


Subject(s)
Quantum Theory
9.
Inorg Chem ; 48(23): 10892-4, 2009 Dec 07.
Article in English | MEDLINE | ID: mdl-19877672

ABSTRACT

Dichloroaluminum benzoate and its adducts with Lewis bases show a large structural variety from molecular complexes to ionic species as indicated by X-ray diffraction, spectroscopic studies, and quantum-chemical calculations.


Subject(s)
Aluminum/chemistry , Benzoates/chemistry , Carboxylic Acids/chemistry , Chelating Agents/chemistry , Organometallic Compounds/chemistry , Crystallography, X-Ray , Ligands , Models, Molecular , Molecular Structure , Quantum Theory
10.
J Chem Phys ; 123(12): 124103, 2005 Sep 22.
Article in English | MEDLINE | ID: mdl-16392471

ABSTRACT

A derivation of the density-functional-theory- (DFT) based reactivity indices in the ensemble unrestricted Hartree-Fock (eUHF) method is presented. The comparison between the properties of the reactivity indices evaluated in one and two sets of spin-orbital approach of the eUHF and hyper-unrestricted Hartree-Fock (UHF) methods are shown. All approaches give similar Fukui function irrespective of methodology used, but significantly differ for the global indices, containing important chemical information, and so their interpretation in terms of DFT- based indices can be questionable. The calculation scheme for the indices using the first- and second-order coupled perturbed eHF equations is proposed. A method for the identification of the spinorbitals involved in the change of the total number of electrons is included. The illustrative examples (water and hydrogen cyanide) show that the ground-state (GS) properties of the (Z +/- 1)-electron systems can be predicted from the GS properties of the Z-electron systems with an accuracy comparable with the UHF calculations. The relaxation effect, important for the HCN system in which a change in the symmetry of the highest-occupied spin-orbital occurs, is effectively predicted.

11.
J Chem Phys ; 123(12): 124102, 2005 Sep 22.
Article in English | MEDLINE | ID: mdl-16392470

ABSTRACT

Correct evaluation of the reactivity indices, such as chemical potential, hardness, and Fukui function demands for the extension of the formalism beyond the integer particle picture. An ensemble approach is used as an extension of the unrestricted Hartree-Fock (UHF) method for noninteger electron number systems. A prescription is given for the construction of an ensemble Fock operator for a system with partially filled spin-orbitals. The comparison between the ensemble HF method and the hyper-HF method in terms of density matrices and spin-orbitals is presented. The equivalence of the equiensemble case and the ensemble UHF case with unequal weight factors is shown.

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