The application of the super-elastic TiNi implant for the functional reconstruction of the tongue in oncology patients

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BACKGROUND

Every year approximately 660,000 new cases of cancer in the head and neck area are diagnosed worldwide, due to which more than 325,000 people pass away [1]. The predominant histological type is the squamous carcinoma (95%) of various degree of differentiation. During the last decade, among the tumors of the head and neck area, a growth is reported in the number of mouth cancer cases, including the tongue cancer. As of today, the incidence of tongue cancer increased at the age group from 20 to 39 years, predominantly among women [2].

The main method for the treatment of patients with locally advanced tumor process in the tongue is the combined one, including the surgical method with further radiation or chemoradiation therapy. The surgical treatment in the extent of radical resection of the tumor (with an offset from the tumor margin being 1.5 cm) and the cervical lymphodissection according to indications remains the leading method for the treatment of malignant tumors of the tongue¹. Performing the extended surgeries for locally advanced stages of tongue cancer with the resection of the oral cavity floor muscles and the mandible often results in the complex defects, which is inevitably associated with the loss of such functions as speech, chewing and swallowing [3]. Radical surgical treatment of locally advanced stages of cancer in the tongue and in the oral cavity floor is often associated with the formation of vast postoperative defects in the lower third of the face [4], due to which, the not less important aspect in the treatment of patients with tongue tumors is performing the reconstructive-plastic surgeries, aimed at the complete functional and social rehabilitation. For solving the tasks of surgical reconstruction of the tongue, the most preferable is the usage of the proprietary tissues of the patient [5], with this, the lack of local tissues in the oral cavity for correcting the defects after glossectomy does not provide the proper quality of speech and nutrition, and in a number of cases results in the disruption of suture lines in the oral cavity with the formation of vast openings (orostomas). The literature sources widely describe the methods of tongue reconstruction with using the submental and the pectoral flaps [6, 7], nevertheless, such reconstructive methods of correcting the vast defects of the tongue did not become the method of choice due to the unsatisfactory functional result, the small volume of soft tissues used, due to the significant atrophy of the flaps in the remote period, as well as due to the development of cicatricial deformation in the donor area (neck), which negatively affects the functional results [8].

The application of the methods of microsurgical reconstruction using the free re-vascularised flaps with sufficient volume allowed for decreasing the number of postoperative inflammatory complications and improving the functional results after radical surgical resections in cases of advanced tongue tumors [9]. However, it is worth noting that all the reconstruction methods in oncology patients, suggesting the use of rotated or free flaps, are accompanied by microcirculation disorders of various degree of intensity. These complications are most frequently related to the consequences of radiation therapy and characterized by the pathological changes in the microcirculation both in the recipient vessels of the neck (in cases of preoperative radiation therapy) and in the tissues of the reconstructive flaps themselves (in cases of adjuvant radiation therapy) [10], which can lead to serious post-operative complications and, in a number of cases, to the complete necrosis of the flap used. During the glossectomy with the resection of the oral cavity floor muscles, the ptosis of the hyoid bone and the throat develops, which negatively affects the swallowing function and often leads to the food aspiration into the airways, due to which, even in cases of correcting the tongue defect by using the musculocutaneous flap, patients do not succeed in reaching the acceptable results of restoring the swallowing function and of the full-scale nutritional rehabilitation [11].

Within the premises of the Department of Head and Neck Tumors of the Scientific-Research Institute of Oncology under the FSBSI “Tomsk National Research Medical Centre” under the Russian Academy of Sciences (SRI of Oncology of Tomsk NRMC) together with the Laboratory of Medical Alloys and Implants with Shape Memory under the FSAEI of Higher Education “National Research Tomsk State University”, a reconstructive methods was developed for restoring the tongue and for improving the functional results after glossectomy. The method includes creating the free re-vascularised musculocutaneous flap and the implantation of the metal weft-knitted mesh made of nickel-titanium (TiNi) for the reconstruction of the tongue and for preventing the ptosis of the hyoid bone and the tissues of the flap used.

Aim — to arrange the clinical approbation of the method of tongue reconstruction after glossectomy using the re-vascularised musculocutaneous flap and the TiNi metal weft-knitted mesh.

METHODS

Research design

Single-center prospective non-randomized research.

Conformity criteria

Inclusion criteria: patients with primary or recurrent cancer of the oral cavity floor staged Т3-4N0-3M0 (III–IVA); age from 18 to 75 years; consent for surgical treatment; patient evaluation result brings 0–2 points with using the scale of the functional status and the quality of life — ECOG (Eastern Cooperative Oncology Group); radical extent of the conducted surgical treatment (R0 based on the results of the intra-operative examination).

Non-inclusion criteria: allergic reactions to the components of medicinal products or elements of the metal weft-knitted NiTi mesh, impossibility of conducting the radical surgical treatment (vast local spreading of the tumor process, substantial concomitant diseases)

Exclusion criteria: the patient’s refusing to undergo further follow-up.

Research facilities

The reconstructive method was developed within the premises of the Department of Head and Neck Tumors of the SRI of Oncology of the Tomsk NRMC together with the Laboratory of Medical Alloys and Implants with Shape Memory under the National Research Tomsk State University. All the patients that were the research participants were receiving treatment and were operated within the premises of the Department of Head and Neck Tumors of the SRI of Oncology of the Tomsk NRMC.

Research duration

The research lasted from 3 to 12 months depending on the patient. The duration of logopedic sessions was 19–20 days in 16–22 days after surgery. The duration of follow-up ranged from 6 to 18 months.

Medical procedure description

Initially, the resection was done for the tongue tissues, the oral cavity floor and the cervical lymphodissection on one side or bilaterally (according to indications). The implant is the mesh of the tricot structure made of the biologically inert superelastic TiNi wire with a thickness of 60 μm (Fig. 1, а). In our earlier research works, it was shown that the tensile strength of the wire is 13% with the tension being 1800 MPа [12]. The results of the computer modeling have demonstrated that the metal weft-knitted TiNi mesh does not break at the deformation levels of up to 16.3%, elastically deforming in these settings up to 8% [13, 14]. The special knitting of the mesh provides the stability of dimensions and the even expansibility in all directions. After the implantation, the TiNi mesh adapts to the longitudinal and the transverse motions of the tissues in the area of the oral cavity floor without loosing the supportive function in terms of the hyoid bone and the throat due to the elastic properties of the mesh (Fig. 1, б).

 

Fig. 1. The scheme of the reconstruction of the oral cavity floor using the metal weft-knitted mesh made of nickel-titanium (TiNi): total view of TiNi metal weft-knitted mesh (a); the scheme of implant fixation in the area of the oral cavity floor (b).

 

After the radical resection stage and after the analysis of the resulting defect in the tongue and in the oral cavity floor muscles, the anterior-lateral or the medial musculocutaneous (depending on clinical situation) flap is isolated from the hip according to the standard method. As mentioned above, the oncological stage of surgery includes the resection of the tissues of the tongue, the oral cavity floor and the neck dissection on one side or bilaterally (Fig. 2, a). The extent of the dermal and the muscular tissues included into the flap depends on the design and the dimensions of postoperative defect. Due to the dermal portion of the flap, tongue reconstruction is done, while the muscular portion is used to fill the defect in the oral cavity floor muscles. In case of the necessity of more adequate access to the area of the oral cavity reconstruction, one can employ the medial mandibulotomy for the purpose of the free distribution of the flap in the oral cavity during the anatomical reconstruction. After this, the dermal portion of the flap is distributed within the oral cavity for restoring the anatomical shape of the tongue and of the oral cavity floor. The vascular pedicle of the flap is introduced behind the mandibular angle in the area of the upper third of the neck with locating it freely (without tension). Then, using the operating microscope and the microsurgical instruments, the application of the microvascular anastomoses is done between the flap vessels and the donor vessels of the neck area (generally, the facial ones). The most frequently performed procedures are the application of a single arterial and two venous anastomoses, after which the blood supply is evaluated in all the flap portions and the thorough hemostasis of the wound is carried out. In case of mandibulotomy, the extra-cortical metallic osteosynthesis is done using the standard titanium plates and the mini-screws. The reconstruction of the oral cavity floor muscles is done by locating the muscle portion of the flap, which is fixated posteriorly to the remaining part of the tongue root and anteriorly to the mandible and to the mobile part of the tongue being reconstructed, and inferiorly — to the body of the hyoid bone. Above the muscle portion of the flap, a fragment of the TiNi metal weft-knit mesh is fixated, having the size corresponding to the area of the defect of the oral cavity floor (Fig. 2, б). The implant made of TiNi metal weft-knitted mesh is fixated to the body and to the greater horn of the hyoid bone using the Prolene 3-0 suturing material (Ethicon, USA), after this follows the maximal up-lifting of the TiNi mesh and fixating it to the area of the lower margin of mandible via the holes pre-formed using the motor system and the drill (1.5–2 mm). After the reconstructive stage of surgery, repeated control of circulation is performed in all the portions of the flap, along with the control of hemostasis, as well as the positioning and the tension of the TiNi metal weft-knitted mesh.

 

Fig. 2. The overall view of the operative wound after glossectomy with the resection of the oral cavity floor muscles and of the mandible on the right side (a); after the reconstruction using the medial musculocutaneous flap from the thigh and the metallic weft-knitted mesh: implant located above the muscular portion of the flap and fixated to the hyoid bone and to the mandible (b).

 

Research findings

Main research outcome: creating the anatomical shape of the tongue and of the oral cavity floor without the ptosis of the hyoid bone and of the reconstructive flap applied; restoration of the speaking and swallowing function in patients.

Methods for registration of outcomes

For the evaluation of positioning of the nickel-titanium mesh and of the status of the reconstruction area, during the postoperative period, the method used was the spiral computed tomography of the facial skeleton and of the soft tissues in the neck area with the bolus intravenous contrasting (Omnipaque) using the Somatom Emotion 6 equipment (Siemens AG, Germany).

For the purpose of ruling out the recurrence of the tumor process or for evaluating the local spreading of the tumor process (if present), all the patients were undergoing the endoscopic examination of the nose, the mouth, the laryngopharynx and the larynx using the rigid endoscopes (with a diameter of 5.8 mm and with a viewing angle of 70°, 30°, 0°) or the flexible fibroscope (with a diameter of 3.5 mm) manufactured by Karl Storz (Germany). For the verification of the primary tumor process or when suspecting the presence of continued growth/recurrence, at the follow-up stages, the targeted biopsy of the tumor was done.

For assessing the regional cervical lymph nodes and the diagnostic of their possible metastatic involvement, the ultrasound examination of the neck area was performed using the Philips Affinity 70 equipment (USA) by the linear probe with a frequency of 10 mHz and by the convex probe with a frequency of 3.5 mHz. When suspecting the presence of metastatic impairment, the fine-needle aspiration biopsy of the lymph node was done under the ultrasonography guidance with further cytological examination.

Histological examination. During the surgical treatment due to the developing recurrence, the sampling procedures were conducted to collect the soft tissues around the nickel-titanium mesh (1 case). The fixation of the tissue samples employed the standard method in the automatic Leica ASP6025 tissue processor (Leica Biosystems, Germany) using the domestically manufactured “Izopren” solution for histological processing (absolute isopropanol, concentration — not less than 99.7%) with an addition of Triton Х15 (octylphenoxypolyethoxyethanol). Later on, histological slices with a thickness of 4–5 μm were prepared from the paraffin blocks. The microtomy was carried out using the HM 430 sled microtome (Thermo Fisher Scientific, USA). The staining of the microscopy slides was done using the hematoxylin and eosin pre-mixed solutions. The staining procedure was carried out using the Varistain Gemini equipment (Thermo Fisher Scientific, USA). The morphological examination was performed using the Axio Scope.A1 light microscope (Carl Zeiss, Germany). The photographic images of the stained histological microslides were obtained using the NIKON ECLIPSE NI microscope digital camera (Nikon Corporation, Japan).

Statistical analysis

The statistical analysis was not done due to the small number of patients.

RESULTS

Research sample (participants)

The research included 6 patients aged 38–57 years with the diagnosed tongue cancer, of which there were three men and three women (Table 1). The distribution of patients by the spreading degree of the tumor process according to the international TNM classification (Tumor, Nodes, Metastasis) was the following: stage T3N0M0 was diagnosed in 2 patients, stage T3N1M0 — in 3 patients and the stage T3N3M0 was diagnosed in 1 patient.

 

Table 1

Clinical characteristics of patients enrolled into the research

Parameter	Patient
	1	2	3	4	5	6
Sex	male	female	female	male	female	male
Age, years	45	55	38	46	57	52
TNM stage	T3N3M0	T3N0M0	T3N1M0	T3N1M0	T3N0M0	T3N1M0
Extent of glossectomy	V	IVb	V	V	IVb	V
Flap	ALT	ALT	PAP	PAP	ALT	PAP
Adjuvant radiation therapy	60 Gr	-	-	60 Gr	60 Gr	60 Gr
Logopedic sessions, n	20	20	19	20	19	20
Follow-up duration, months	12	11	10	7	5	3

 

The reconstructive surgery due to the presence of recurrence after the radical radiation therapy (66–70 Gr) arranged in other clinics, was performed in 2 patients. All the patients underwent the glossectomy and the resection of the oral cavity floor muscles. Bilateral neck dissection was done in 4 patients, two other patients had the unilateral neck dissection.

In order to replace the defects of the tongue and of the oral cavity floor, in 3 cases, the perforated musculocutaneous flap from the medial hip area was used (the PAP flap), in another 3 cases, the flap was taken from the anterior-lateral surface of the thigh (ALT flap). The follow-up period ranged from 3 to 12 months.

All the patients underwent the types IVb and V glossectomy in accordance with the classification by M. Ansarin et al. [15].

All the patients have received a course of speech rehabilitation within a period ranging from 16 to 22 days after the surgical treatment. The duration of logopedic sessions was 19–20 days.

Main research outcome

In all the cases of the conducted reconstructive surgeries, the restoration of the tongue shape was successful. Restoring the anatomical shape of the tongue and of the oral cavity floor without the ptosis of the hyoid bone combined with the reconstructive flap has allowed for more comprehensively and early restoring the speech and the swallowing functions. No inflammatory changes in the area of the reconstruction and of the TiNi mesh implantation were found in any of the cases. One patient had a local recurrence 4 months after surgery, which was the indication for repeated intervention. There were no reported cases of post-operative complications related to the usage of the TiNi mesh.

After 3 months, all the patients underwent the spiral computed tomography of the facial bones and neck (contrasted) for the purpose of evaluating the status of the reconstructed area, namely, the position of the flap and the TiNi mesh implant (Fig. 3, а): in all the patients, the shape of the reconstructed tongue similar to the anatomical one was achieved without the significant ptosis of the soft tissues to the neck area; no dislocation was found in the TiNi mesh implant; sufficient pexy was shown for the hyoid bone and the throat to the mandible area (Fig. 3, б).

 

Fig. 3. Post-operative follow-up of the patient (3 months after reconstruction): a — multispiral computed tomography: in the area of the oral cavity floor, the findings include the fixated TiNi mesh implant (shown by the arrow); b — the appearance of the reconstructed tongue: the anatomic shape of the tongue is visualized.

 

Undesirable phenomena

In one case, in 4 months after the reconstruction, repeated surgery was arranged due to the presence of cancer recurrence, which allowed for evaluating the status of the reconstructed area (Fig. 4): the mesh implant was located within the muscle tissue with no signs of dislocation, no visible manifestations of inflammation and without developing the rough connective-tissue capsule (Fig. 5). According to the results of histological examination of the soft tissue fragment (muscles and subcutaneous-fatty tissue) around the TiNi mesh implant, the sample contains the fibrous connective tissue with signs of inhomogeneous edema and insignificant lymphoid infiltration, with a tendency to the formation of small lymphoid aggregates in the part of fields of view. Separate foci contain fragments of muscle tissue, loosened due to the accumulation of edema fluid in the intercellular spaces. In all the fragments, the findings included the multiple gigantic cells, the focal diapedetic hemorrhages, the accumulations of hemosiderophages, xanthomatous cells and macrophages (Fig. 6). These morphological findings correspond to the mild phase of the chronic productive inflammation, which is characteristic for the normal tissue reaction in response to the implantation of the biocompatible non-resorbable material.

 

Fig. 4. The overall view of the operative wound after the reconstruction using the musculocutaneous flap and the implant made of TiNi metallic weft-knitted mesh: the mesh implant is located above the muscular portion of the flap and fixated to the hyoid bone and to the mandible (а); surgical treatment in 4 months due to the recurrence after the conducted reconstruction: visualized area of the mesh implant positioning, with the implant completely submerged into the muscular tissue (b).

 

Fig. 5. Reconstruction area (magnification) in 4 months: within the muscle tissue and along its surface, the structure of the mesh implant is visualized (arrows), which is completely integrated into the muscular tissue with no visible signs of inflammatory reaction or developing the coarse connective tissue.

 

Fig. 6. Histological specimens prepared from the fragment of soft tissues around the TiNi mesh implant (implantation duration — 4 months), staining with hematoxylin-eosin: the findings are the muscular and the connective tissue with signs of swelling, accumulations of hemosiderophages; inhomogeneously plethoric vessels; abundance of gigantic multinuclear cells (a); lymphoid infiltration, gigantic cells, hemosiderin (b); lymphoid aggregate (c); multinucleated foreign body giant cells (d; arrows).

 

DISCUSSION

The restoration of the tissues of the tongue and the oral cavity floor after glossectomy represents a complex clinical task. The widely used free flaps can replace only the part of tissues, not impairing the biomechanics of the muscular system of the oral cavity floor, which is confirmed by the high percentage of postoperative functional disorders. The postoperative ptosis of the hyoid bone and of the larynx plays a significant role in the development of dysphagia. The traditional methods of hyoid bone fixation have certain limitations [16, 17] and, in a number of cases, they are associated with the increased rate of postoperative complications in oncology patients.

The method developed by us for the reconstruction after glossectomy with the fixation of the hyoid bone to the mandible by means of using the superelastic TiNi mesh is meant to solve the abovementioned problems. Using the knitted mesh made of TiNi alloy provides the reliable and stable fixation of the hyoid bone to the mandible, while the superelasticity of the TiNi alloy is consistent with the biomechanics of the oral cavity floor muscles during the swallowing act. The notable benefit of the knitted TiNi mesh is its integration into the employed free flap without the formation of the rough cicatricial tissue: instead, it creates the tissue similar to the fascial one, which gives the pre-set shape to the reconstructed muscles of the oral cavity floor.

After surgery, within 2 weeks, the patients were undergoing the speech rehabilitation at the Department of Head and Neck Tumors of the SRI of Oncology of the Tomsk SRMC. The logopedic rehabilitation has allowed the patients to improve the speech function and to restore the ability to eat meals of soft and semi-soft consistency via the mouth without aspiration. The restoration of the anatomical shape of the tongue and of the oral cavity floor without the ptosis of the hyoid bone has provided an adequate and early restoration functions of the tongue and of the oral cavity.

The application of the TiNi mesh for the reconstruction of the oral cavity floor was not the contraindication for the adjuvant radiation therapy and it did not result in the increased incidence of radiation-induced reactions in the skin and the soft tissues of the neck. Besides, the presence of knitted TiNi mesh did not hamper the visualization of the soft tissues of the neck area and did not create significant artifacts upon the spiral computed tomography, which is shown by the fact of one case of detecting the tumor recurrence in 4 months of follow-up. The repeated surgery due to the presence of tumor recurrence went without any technical difficulties related to the presence of TiNi mesh in the area of the repeated surgery. The scar tissue in the area of the implanted mesh was unclearly pronounced. The knitted TiNi mesh was easy to cut with the standard surgical scissors, however, it is worth noting that when using the monopolar coagulator in the area of the TiNi mesh, sparkling was observed (for its prevention, the bipolar electric coagulator was used).

The speech rehabilitation after the glossectomy with reconstruction employing the developed method results in the improvement of speech and swallowing in the majority of patients. The conducted research has demonstrated the improvement of tongue mobility in 4 of 6 patients, and in 5 patients, to the end of speech rehabilitation, there were no swallowing difficulties.

The obtained results demonstrate that reconstruction of the tongue and of the oral cavity floor after the vast resections is applicable even in cases of recurrence after the radiation therapy. The musculocutaneous flaps used have allowed for conducting the effective reconstruction of the tongue and of the oral cavity floor. The TiNi mesh used for the fixation of the hyoid bone to the mandible provides a reliable fixation of the throat, which promotes the better restoration of the swallowing function and, besides, it provides and elastic frame for the oral cavity floor muscles, facilitating the restoration of the optimal anatomical shape in this area. The natural movements of the neck, which could potentially negatively affect the integration of the TiNi mesh with the surrounding tissues, did not lead to the encapsulation with signs of active inflammation and dislocation, which can indicate the high biocompatibility of the TiNi mesh and its applicability for the reconstruction of the mobile tissues and body parts.

Research limitations

The limitation of the research is its single-center type and the small number of enrolled patients, not allowing for obtaining the results with statistical significance.

The research was analyzing only one reconstructive method with using the mesh made of nickel-titanium. The small follow-up period does not allow for suggesting on the remote results of the reconstruction.

CONCLUSION

The developed reconstruction method allows for performing the effective restoration of the tongue and of the oral cavity floor due to using the musculocutaneous flap taken from the thigh and using the TiNi metal weft-knitted mesh during the surgical treatment of the oncology patients after glossectomy with achieving the maximal anatomic reconstruction of the tongue and of the oral cavity floor, including the creation of the favorable conditions for further nutritional and speech rehabilitation without increasing the rate of postoperative complications.

ADDITIONAL INFORMATION

Author contributions: D.Е. Kulbakin, defining the concept, conducting the research, methodology, validation, writing the draft of the manuscript, reviewing and editing the manuscript; Е.L. Choynzonov, defining the concept, validation, managing the research; V.О. Tskhai, Е.А. Krasavina, conducting the research, methodology, writing the draft of the manuscript; Е.S. Marchenko, fund raising, administering the project; G.А. Baigonakova, visualization, validation; К.М. Dubovikov, visualization, writing the draft of the manuscript. Thereby, all authors provided approval of the version to be published and agree to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Ethics approval: The research was carried out with following the principles of voluntariness and confidentiality in accordance with “The Fundamental Principles of the Law of the RF on the Health Protection of the Citizens”. The permission was granted from the Ethics Committee of the SRI of Oncology under the FSBSI “Tomsk National Research Medical Centre” under the Russian Academy of Sciences for the conduct of the research (protocol No. 16, dated 2021 Dec 09). All the research participants have voluntarily signed the informed consent form prior to the inclusion into the research program (upon hospitalization to the SRI of Oncology).

Funding sources: The study was carried out with financial support from the Ministry of Science and Higher Education of the Russian Federation (Agreement No. 075-15-2025-607 dated 01/07/2025)

Disclosure of interests: The authors declare that they have no direct or potential competing connected with publication of this article.

Statement of originality: All results of the work are original.

Data availability statement: The authors do not provide access to the data obtained during the preparation of this article.

Generative AI: Generative AI technologies were not used for this article creation.

 

¹ National Comprehensive Cancer Network [Internet]. Clinical practice guidelines in oncology. Head and neck cancers. Version 4.2024. Access mode: https://www.nccn.org/guidelines/guidelines-detail?category=1&id=1437 Reference date: 15.12.2025.

About the authors

Denis E. Kulbakin

Tomsk National Research Medical Center

Email: kulbakin_d@mail.ru
ORCID iD: 0000-0003-3089-5047
SPIN-code: 3898-9456

MD, PhD

Russian Federation, Tomsk

Evgeny L. Choynzonov

Tomsk National Research Medical Center

Email: center@tnimc.ru
ORCID iD: 0000-0002-3651-0665
SPIN-code: 2240-8730

MD, PhD, Professor, Academician of the Russian Academy of Sciences

Russian Federation, Tomsk

Vladislav O. Tskhay

Tomsk National Research Medical Center

Email: kragnan@gmail.com
ORCID iD: 0009-0003-3257-9002
SPIN-code: 6296-4573
Russian Federation, Tomsk

Elena A. Krasavina

Tomsk National Research Medical Center

Email: krasavinaea@mail2000.ru
ORCID iD: 0000-0002-8553-7039
SPIN-code: 2111-3721

PhD

Russian Federation, Tomsk

Ekaterina S. Marchenko

Tomsk State University

Email: 89138641814@mail.ru
ORCID iD: 0000-0003-4615-5270
SPIN-code: 7116-2901

PhD, Assistant Professor

Russian Federation, Tomsk

Gulsharat A. Baigonakova

Tomsk State University

Email: gat27@mail.ru
ORCID iD: 0000-0001-9853-2766
SPIN-code: 7063-1700

PhD

Russian Federation, Tomsk

Kirill M. Dubovikov

Tomsk State University

Author for correspondence.
Email: kirill_dubovikov@mail.ru
ORCID iD: 0000-0003-0823-7208
SPIN-code: 9042-5741
Russian Federation, Tomsk

References

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