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It is emphasized in the article that thanks to the discovery of D.I. Mendeleev and the Periodic Table of chemical elements existing for more than 150 years, as well as the international table IUPAC, chemistry has been actively developing and keeps developing. A new model for arranging chemical elements in the form of a three-dimensional matrix has been proposed. This makes it possible to predict new elements with the designation of nuclear masses and the electronic structure of shells. There have been developed new patterns according to the cyclicity (block structure) of horizontal rows and the structure of vertical groups and their physical conception have been specified.

We study the growth of product sets in some finite three-dimensional matrix groups. In particular, we prove two results about the group of $2\times 2$ upper triangular matrices over arbitrary finite fields: a product set estimate using techniques from multiplicative combinatorics, and an energy estimate using incidence geometry. The energy method gives better quantitative results, but only applies to small sets. We also prove an energy result for the Heisenberg group., Comment: 20 pages

A novel method to obtain porous three-dimensional chitosan-based matrices has been developed. The structure is characterized by an interconnected system of pores, with controlled diameter by varying the concentration of chitosan and the nature of the solvent. The material is biodegradable, biocompatible, with high adhesion to fibroblasts and promotes its proliferation.

Hyaluronan is a ubiquitous constituent of mammalian extracellular matrices and, because of its excellent intrinsic biocompatibility and chemical modification versatility, has been widely employed in a multitude of biomedical applications. In this article, we will survey the approaches used to tailor hyaluronan to specific needs of tissue engineering, regenerative and reconstructive medicine and overall biomedical research. We will also describe recent examples of applications in these broader areas, such as 3D cell culture, bioprinting, organoid biofabrication, and precision medicine that are facilitated by the use of hyaluronan as a biomaterial.

Sustainable and controlled delivery of drugs is at the centre of a huge amount of undertaken researches. The ability of hydrogels, high water content materials, to achieve a local and delayed-delivery has already been demonstrated for a wide variety of therapeutic agents and various polymer natures. In particular, chitosan, a natural polymer, stands out as a first choice material for hydrogels elaboration in biomedical, cosmetic, and health related applications, owing to its interesting properties (as biocompatibility, biodegradability, antimicrobial capacity, and mucoadhesivity). Moreover, chitosan also allows drugs to go easier through biological barriers. The main objective of this review is to report the various uses of chitosan hydrogels as drug delivery devices to control and/or delay the release of drugs loaded into their three dimensional matrix. A wide spectrum of corresponding biomedical applications of these systems can be encountered in the literature, whatever the physicochemical nature of drugs (hydrophilic, hydrophobic, macromolecular), as detailed in this review.

During metastasis, cells can use proteolytic activity to form tube-like “microtracks” within the extracellular matrix (ECM). Using these microtracks, cells can migrate unimpeded through the stroma. To investigate the molecular mechanisms of microtrack migration, we developed an in vitro three-dimensional (3D) micromolded collagen platform. When in microtracks, cells tend to migrate unidirectionally. Because focal adhesions are the primary mechanism by which cells interact with the ECM, we examined the roles of several focal adhesion molecules in driving unidirectional motion. Vinculin knockdown results in the repeated reversal of migration direction compared with control cells. Tracking the position of the Golgi centroid relative to the position of the nucleus centroid reveals that vinculin knockdown disrupts cell polarity in microtracks. Vinculin also directs migration on two-dimensional (2D) substrates and in 3D uniform collagen matrices, as indicated by reduced speed, shorter net displacement, and decreased directionality in vinculin-deficient cells. In addition, vinculin is necessary for focal adhesion kinase (FAK) activation in three dimensions, as vinculin knockdown results in reduced FAK activation in both 3D uniform collagen matrices and microtracks but not on 2D substrates, and, accordingly, FAK inhibition halts cell migration in 3D microtracks. Together these data indicate that vinculin plays a key role in polarization during migration.

Nowadays, collaborative knowledge management (CKM) is well accepted as a decisive asset in the field of networked enterprises and supply chains. However, few knowledge management initiatives have been performed successfully because, in most cases, the barriers that hinder the CKM process are unknown and misunderstood. Currently, the research reveals different uni- and bi-dimensional barriers&rsquo, classifications, however multi-dimensional approaches provide a better view of the complexity in the area of CKM. Therefore, this paper proposes the three-dimensional matrix of collaborative knowledge barriers taking into account: (i) perspectives, (ii) levels and (iii) barriers blocks to provide a reference way to audit the CKM barriers, and thus, in further research, focus on the corrections and adjustments to guarantee the success while implementing a CKM project.

At present the majority of association rule mining algorithm only uses support and confidence to evaluate association rules, association rules which may contain a large number of redundant, meaningless, Introducing the concepts of hyper-graph and system and exploring to construct the hyper-graph on the model of three-dimensional matrix. According to the characteristics of Big Data, the new hyper-edge definition method is adopted combining the concept of system, thus improving the processing capacity.

This article considers the classification of matrix superpotentials that corresponds to exactly solvable systems of Schrodinger equations. Superpotentials of the following form are considered: $W_k = kQ + P + \frac1kR$, where $k$ --- parameter, $P, Q$ and $R$ --- hermitian matrices, that depend on a variable $x$. The list of three-dimensional matrix superpotentials is presented explicitly., Comment: 13 pages, grammar corrections were added

A novel lingual epithelial organoid culture system using a three-dimensional (3D) matrix and growth factors has recently been established. In the culture system, organoids with multilayered squamous keratinized epithelium and typical morphological features of filiform papillae are generated from single lingual epithelial cells at a high efficiency. The culture system is created in order to observe the differentiation and maturation process of each lingual epithelial stem cell and to observe abnormal organoid formation from malignant cells obtained from carcinogen-treated mice. Thus, our culture system will contribute to the advancement of research into the regulatory mechanism of lingual epithelium and the underlying mechanisms of carcinogenesis.

AIMS To assess the accuracy of different hardware and software settings for left ventricular (LV) volume quantification in children using real-time three-dimensional echocardiography (RT3DE). METHODS AND RESULTS The impact of different matrix transducers (IE 33, X3-1 and VIVID 7, V3) and quantification software settings [TOMTEC; contour-finding activity (tCFA) values ranging from 30 to 70 U] on the accuracy of LV indices was tested in 24 healthy children/adolescents (median = 12.6 years) and 25 paediatric patients with Tetralogy-of-Fallot (TOF) (median = 7.3 years) with abnormally shaped ventricles. RT3DE was compared with cardiovascular magnetic resonance (CMR) volumetry as reference. Best agreement (Bland-Altman analysis) was achieved using a tCFA value of 30 U. Applying the V3 device, end-diastolic volume (EDV) and end-systolic volume (ESV) were underestimated by 14.8 +/- 10.6% (mean +/- SD) and 11.2 +/- 16.3%, respectively (r = 9.42, P < 0.001 and r = 0.937, P = 0.003); with the X3-1 system 24.2 +/- 11.0 and 14.6 +/- 15.2%, respectively (r = 0.951, P < 0.001 and r = 0.912, P = 0.001). Negligible differences

The new 3D models of the prestressed symmetrical and unsymmetrical ultrasonic sandwich transducers are described in this article. The sandwich transducers are modeled through the application of a 3D matrix model of piezoceramic rings and discs, recently proposed by the authors. Theoretical analyses prove the proposed models as simple and easy to calculate, particularly suitable for the investigation of coupled vibrations cases. Experiments show that the measured resonance and antiresonance frequencies are in good agreement with the predicted results. Compared with traditional 1D models and methods, the results obtained by the proposed models matched better with the experimental results.

Arthroskopische Rekonstruktion der Gelenkflache mit resorbierbaren Zelltragern zur Behandlung vollschichtiger Knorpeldefekte und damit zur langfristigen Vermeidung einer Progression der Arthrose. Vollschichtige, bis auf den Knochen reichende Knorpeldefekte im Kniegelenk. Fortgeschrittene Arthrose, Arthritis, Knochennekrosen. Arthroskopisches Debridement des Knorpeldefekts, Ausmessen der Defektgrose, Anpassen des Implantats, Einfuhren in das Gelenk und Fixation. Aktive und passive Gelenkmobilisation, schmerzadaptierter Belastungsaufbau, ggf. initiale Entlastung in Abhangigkeit von Lokalisation und Grose des Defekts. 45 Patienten mit einem Durchschnittsalter von 39 Jahren wurden in der beschriebenen Technik behandelt. Im Mittel waren 3,3 Knorpeloperationen vorausgegangen. Die ersten 20 Patienten mit einem Nachuntersuchungszeitraum von 2 Jahren und einer mittleren Defektgrose von 4,52 cm2verbesserten sich in ihren klinischen Zustand nach dem modifizierten Cincinnati-Score von 3,5 auf 6,2 Punkte (Maximum 10 Punkte). 17 Patienten wurden arthroskopisch transplantiert. Schlechtere Ergebnisse wurden bei Defekten der Patella oder der Tibia erreicht. Es traten keine spezifischen Komplikationen auf.

Intravascular catheters are the most common cause of nosocomially acquired bloodstream infections. Bacteria found adhering to the intraluminal surfaces of catheters are the principal source and cause of these infections. Adherent bacteria overtime are known to form multicellular communities which become encased within a three dimensional matrix of extracellular polymeric material known as biofilms, which are thought to be responsible for persistent infections. Consequently, a number of technologies have been developed to help prevent and control biofilms in intravascular catheters. One such approach involves impregnating catheter material with antimicrobial agents. Unfortunately these methods are not universally effective in preventing catheter-related biofilm infections. Technologies that utilise antimicrobials, as catheter locks have been shown to have more potential for preventing biofilm formation and reducing the incidences of catheter related bloodstream infections (CRBSI). This article discusses the significance of biofilms in intravascular catheters and determines whether the treatments available today are proving to be effective for controlling biofilms and draws attention to future avenues which are being investigated to control biofilms and therefore CRBSI.

Let be the symmetrical group acting on the set and . Consider the set The main result of this paper is the following theorem. If the number of set entries is more than , then there exist entries such that , , and . The application of this theorem to the three-dimensional assignment problem is considered.

In front of the actual limitations in the treatment of end-stage HF, there is a clinical demand for alternative therapy concepts in order to further increase clinical outcome and to find customized therapy concepts for patients suffering from end-stage heart failure. With the advance of the tissue engineering concept, new approaches to the treatment of HF are being proposed and scientifically explored. A recently introduced strategy in the tissue engineering field is named whole-organ tissue engineering (WOTE) aiming at the in vitro generation of an entire organ in its anatomic integrity and functional capacity. This chapter is dedicated to cardiac WOTE, also termed whole-heart tissue engineering (WHTE). Beside clinical background and competing experimental approaches this chapter will review current concepts of decellularization, repopulation strategies for whole organ scaffolds, and possible sources of donor cells for organ engineering. Finally, the relevance and feasibility of in vitro conditioning of tissue-engineered whole hearts using bioreactor technology are discussed.

This paper describes the use of localized transient gene therapy for the augmentation of fracture healing. It introduces a method involving the delivery of plasmid deoxyribonucleic acid via a three dimensional matrix into a wound, with in vivo transfection of wound repair cells resulting, their subsequent expression of factors that condition the wound site and the promotion of healing. Based on experience with critical and noncritical defect models in small and large animals, the potential advantages of this approach are discussed and experimental evidence of promoting bone formation is provided. The studies show the potential of this technology not only to promote bone healing but also to repair or to regenerate other connective tissues.

Two-dimensional combinatorial matrix class was found by Richard A Brandi in his book Combinatorial Matrix Class in 2006. In this book, he gave us the definition of this matrix, proves its existent theory, and analyzes its construction. In this paper, we define the three-dimensional combinatorial matrix (TDCM) class \( A(R,\,S,\,T) \) basic of two-dimensional combinatorial matrix class. Then we discuss the existence and construction of this matrix, and built a special class of Matrix in TDCM.

Introduction. We evaluate the midterm results of thirty patients who underwent autologous chondrocytes implantation for talus osteochondral lesions treatment.Materials and Methods. From 2002 to 2009, 30 ankles with a mean lesion size of 2,36 cm2were treated. We evaluated patients using American Orthopaedic Foot and Ankle Surgery and Coughlin score, Van Dijk scale, recovering time, and Musculoskeletal Outcomes Data Evaluation and Management System.Results. The mean AOFAS score varied from 36.9 to 83.9 at follow-up. Average of Van Dijk scale was 141.1. Coughlin score was excellent/good in 24 patients. MOCART score varied from 6.3 to 3.8.Discussion. This matrix is easy to handle conformable to the lesion and apply by arthroscopy. No correlation between MRI imaging and clinical results is found.Conclusions. Our results, compared with those reported in literature with other surgical procedures, show no superiority evidence for our technique compared to the others regarding the size of the lesions.

Einleitung: Hauptprobleme des Tissue Engineerings von komplexen Gewebestrukturen liegen in den nur eingeschränkten Möglichkeiten, Zellen dreidimensional in einer Matrix anzuordnen, den erwünschten Zelltyp in einem hohen Reinheitsgrad zu platzieren und in der nur unzureichenden Versorgung[for full text, please go to the a.m. URL], 127. Kongress der Deutschen Gesellschaft für Chirurgie

We consider a class of positive linear maps in the three-dimensional matrix algebra, which are generalizations of the positive linear map constructed by Choi in the relation with positive semidefinite biquadratic forms. We find conditions for which such maps are completely positive, completely copositive, decomposable, and two-positive.

A double matrix hybrid coded genetic algorithm (DMHGA) is presented to solve the unit commitment (UC). The DMHGA chromosome consists of three-dimensional matrix representing the UC schedule, it effectively uses the binary-coded genetic algorithm to solve the unit commitment up/down problem and the real-coded genetic algorithm based on the equal incremental-cost criterion to solve the power economic dispatch problem, this modification helps to explore the search space very effectively, It generates better solutions than the other methods. Problem formulation, representation and the simulation results with systems of up to 10 units and 24-h scheduling horizon are presented. The results show that the DMHGA has strong ability in global search and efficient.

The purpose of this study was to evaluate the (ultra-) morphology, biochemical behavior, and activity of ovine chondrocytes seeded on a matrix consisting of three types of collagen (I, II, III) with two different degrees of UV crosslinking. Ovine articular chondrocytes were isolated from stifle joints and seeded on both types of UV-crosslinked collagen matrices, as well as on non-crosslinked sponges, and cultured for 12 h, 7 days, 14 days, and 21 days. Histological analysis, electron microscopy, biochemical assays for glycosaminoglycans, and real-time quantitative PCR for collagens were performed for cell-seeded and unseeded matrices. There was no dramatic difference in the morphology and bioactivity of the cells; however, concerning handling characteristics and integrative stability, both types of crosslinked sponges were superior to non-crosslinked constructs. The results demonstrate that ovine articular chondrocytes express their phenotype in a sponge consisting of collagen; furthermore, because of mechanical reasons, non-crosslinked matrices cannot be recommended for implantation in vivo.

The prevailing paradigm is that T cell differentiation is dependent on interactions between stem cells and neuroectodermal thymic cells in the context of a three-dimensional environment. We evaluated the utility of a three-dimensional matrix, the Cytomatrix, to facilitate T cell differentiation. Thymus stroma grown on the Cytomatrix and seeded with hematopoietic progenitors was observed to support the development of both CD4(+) and CD8(+) T cells. Murine transgenic models used to address T cell selection demonstrated that both positive and negative selection was maintained in the context of MHC Class I. These data demonstrate that this in vitro system using neuroectoderm tissue is capable of the efficient production of T cells from hematopoietic progenitors and presents the possibility of generating and adoptively transferring immune cells to patients.

Purpose: We evaluated outcomes of orthotopic heart transplantation (OHT) using donors with left ventricular hypertrophy (LVH) and assessed changes in LV wall thickness in patients who received a donor hearts with or without LVH. Methods and Materials: We reviewed 427 patients who had OHT: 62 received hearts with LVH (interventricular septum (IVS) or posterior wall (PW) thickness 12 mm) by echocardiography and 365 patients without donor LVH. Results: Mean recipient age was 56 11 and donor age 30 2 yrs. Recipient age, gender, UNOS status, indications for OHT, and hemodynamics were similar in both groups. Ischemic time 240 min occurred only in patients with LVH (6%, p 0.03). The mean donor age was greater in the LVH group (35 12 vs 29 12, p 0.001) and they had higher rates of intracranial hemorrhage (38% vs 15%), p 0.001). Other donor characteristics were similar. LV wall thickness (LVWT) was increased in the LVH group compared with non-LVH donors (IVS: 12.6 1.9 vs 8.5 1.1, PW: 12.7 1.0 vs 9.0 1.0 mm, p 0.0001). Mild LVH (LVWT 12-13 mm) was found in 42%, moderate ( 13-17 mm) in 53% and severe ( 17 mm) in 5% of donors. Median follow-up was 3.8 yrs (range 0 to 17 yrs). Significant regression of LVH occurred (IVS: -1.6 2.0 mm, p 0.0004, PW: -1.8 0.2 mm, p 0.001) at mean followup of 4 2 yrs. The mean IVS: 1.1 0.2 vs 1.1 0.1,p 0.2 , PW: 1.1 0.2 vs 1.1 0.1,p 0.5 and rates of patients with LVH (38% vs 32%, p 0.5) were similar in both groups at followup. Recipients of hearts with and without LVH had similar 30 day (1.6% vs. 3.3%, p 0.7) and 1 yr mortality (3.5% vs 9.5%,p 0.2). Long-term survival was similar in the two groups, p 0.11; survival estimates (7 yrs) were 66 1% vs 57 3%. The incidences of rejection and graft CAD were similar in the two groups. Multivariate analysis revealed no evidence that donor LVH was associated with increased mortality. Conclusions: Shortand long-term survival , LV wall thickness and rates of LVH at follow-up were similar in both groups, suggesting that donor hearts with mild and moderate LVH can be successfully used in OHT.

A simple method is described for the culturing of chondrocytes in a three dimensional matrix of agarose that is overlaid with growth media. Procedures for the examination of the embedded cells at the electron microscopic level are given.

The behaviour of latex films of copolymers of ethyl acrylate and N-methylolacrylamide is studied and it is shown that during the process of film formation a special type of globular network is formed. Subsequent heat treatment of the films in the presence of a crosslinking agent has a marked effect on the compactness of this network. Films of this unusual structure may be regarded as micro-composite materials, consisting of a continuous, three dimensional matrix with globules of linear polymer included within it. The mechanical behaviour of such films is mainly dependent on the properties of the matrix.

A strategy of a systematic comparison is developed in which the valuation parameters and the influencing parameters are put in order in a three dimensional matrix. The performance of a bioreactor construction is then evaluated with a biological test system that has representative medium properties and where all important parameters of microbial growth are known. This strategy is applied to four bioreactor constructions and to low viscous bacteria and yeast systems with and without foam formation. On the basis of this data set the performances of the different bioreactors are compared.

Summary A technique is described for preparing a three-dimentional semisolid rigid matrix for studying the inactivation of biological material suspended in a nonaggregated dry state. Various substances were compared for preparing supportive matrices and tested for recovery of T 1 phage before and after UV radiation. One per cent methylcellulose was selected as the matrix of choice since good survival of the T 1 phage lysate was present prior to radiation, and this matrix was highly UV transparent. The protective effect of additives against UV inactivation was studied, and a combination of lactose glutamate N-Z-amine and carbon black was shown to protect completely against inactivation and also to protect against nonspecific inactivation unconnected with the radiation.

A lower bound is obtained for the plane term rank of a three dimensional matrix in which each of the horizontal two dimensional matrices has constant row and column sums.

Cancer bioassay implies the capacity to predict the clinical behavior of a neoplasm as a result of studying a specimen of it as living tissue in the laboratory. There are at least two behavioral qualities about which prognostic information is desirable. First, we should like to be able to differentiate between tumors that are probably cured after surgery or radiation and those that are likely to recur as metastases. Second, we should like to recognize those tumors that will respond favorably to chemotherapeutic agents or irradiation and those that will be resistant to such treatments. Ideally, the definition and measurement of specific biochemical parameters that can be correlated with future clinical behavior would be desirable. None has yet been found. At the present stage of our understanding, we think it unlikely that well-defined biochemical indices will soon be found in view of the complex physiologic events already identified as being involved in the phenomena of malignancy, and the indication that still other factors await adequate description as well as reproducible experimental manipulation.

Dr. Leighton has developed a technique that appears to be particularly useful for studying the behavior of tumor cells in forming organized patterns and for examining interactions between tumor cells and normal tissues in vitro. With such three-dimensional preparations, the usual histologic techniques and interpretations can be applied more readily than with two-dimensional substrate cultures. Since the sponge is providing a three-dimensional support for cell outgrowth, the conformation of the sponge surfaces might influence the architecture of the culture. However, it appears that the cells fill the interstices and in these lacunae organize into acini, cords, glands, and other structures. For this reason, I wonder if the size and arrangement of pores is not critical. It would seem that they must be relatively small and yet large enough to permit moderate flow of nutrients and development of organoid structures.