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Jurgita Gailite, Agnese Mikilpa-Mikgelba, Ieva Siliņa, Ināra Kirillova, Una Lauga-Tuņina, Iveta Dzīvīte-Krišāne and Dace Gardovska

Abstract

The world has seen a rise of type 2 diabetes mellitus in children during the last 20 years. It is proposed that this increase is due to unhealthy eating habits, increasing obesity, especially among teenagers, and better diagnostics. The main risks associated with diabetes are microvascular and macrovascular complications, which can lead to early disability and premature death. The aim of our study was to identify children with type 2 diabetes mellitus or impaired glucose tolerance and investigate associated comorbidities at the time of diagnosis in the Children’s Clinical University Hospital in Latvia. A retrospective analysis was performed of all children with type 2 diabetes mellitus or glucose tolerance impairment from 2002 till 2013, who were treated in Children’s Endocrinology Centre. According to inclusion criteria, 57 patients were selected of whom 24 (42%) had type 2 diabetes mellitus and 33 (58%) had impaired glucose tolerance. Body mass index was analysed according to percentile and all patients were found to have excess weight. In children with type 2 diabetes mellitus, all patients had body mass index over the 99th percentile. Arterial hypertension was found in 66.7% and dyslipidemia in 54.2% type 2 diabetes mellitus patients. From all type 2 diabetes mellitus patients, 71% (n = 17) were girls and they had statistically significantly higher total cholesterol (p = 0.02) and low-density lipoprotein (p = 0.003) levels. Considering, that girls with type 2 diabetes mellitus have high cardiovascular risk in adulthood, it is very important not only to achieve normal glucose levels early, but also to treat comorbidities, to reduce further microvascular and macrovascular complication risk.

Open access

Carla Johnen and Ilva Daugule

Abstract

Neonates typically have a physiological weight loss (PWL) during the first days of life. Several studies about PWL and its influencing factors have been performed worldwide, resulting in the development of normative charts to identify high risk neonates. Up to now there is neither a study about PWL in Latvia nor charts developed for the Baltic region. The objective of the study was to analyse PWL and associated factors in Latvian neonates as well as to evaluate the possibility to use PWL charts of the American Academy of Paediatrics (AAP). The study included data (gestational week, delivery type, sex, feeding type, health status) of 220 Latvian newborns treated in the neonatology department of Children Clinical Hospital Gaiļezers and in- an out-patient praxis in Riga. Their mean PWL was compared among neonates with different factors and plotted on PWL charts. The mean PWL was 6.4% (SD ± 2.31%) and in univariate analysis it was associated with feeding type (p = 0.06) and health status (p = 0.01). In multiple regression analysis PWL was significantly associated with health status (p = 0.01). The usage of AAP charts could be generally recommended to identify high risk neonates, but development of charts for the Baltics should be discussed..

Open access

Jurijs Nazarovs, Regīna Kleina and Sandra Lejniece

Abstract

CD56, p53, and Cyclin D1 detection in plasma cells (PC) can help to predict prognosis of multiple myeloma (MM). Clinical and biochemical prognostic parameters were analysed in a group of 122 patients with primary diagnosed MM in the period 2011–2015. Bone marrow biopsies were analysed with Cyclin D1, p53, CD56 antibodies. Statistical analysis was performed using Microsoft Excel 2010 and Graph Pad Prism 5. Lack of CD56 expression and p53-positivity were significantly correlated with a low glomerular filtration rate (GFR), low platelet count and haemoglobin level, as well as with high serum creatinine levels. Patients with Cyclin D1 expression in PC had a significantly higher serum calcium level and more common osteolytic lesion in bones. CD56- negative as well as p53, Cyclin D1-positive groups had advanced Salmon–Durie MM stages by and significantly higher ß2-microglobulin. Expression of p53, Cyclin D1 and lack of CD56 antigen in PC are negative predictive factors in cases of MM, as these patients were diagnosed as having late Salmon–Durie stage and higher ß2-microglobulin level. Expression of p53 and lack of CD56 antigen in PC is associated with an increased creatinine level in blood and decreased GFR; therefore, these are criteria for chronic renal failure progression and poorer prognosis of MM.

Open access

P. Devaki, S. Sreenadh, K. Vajravelu, K. V. Prasad and Hanumesh Vaidya

Abstract

In this paper, the peristaltic wave propagation of a Non-Newtonian Casson liquid in a non-uniform (flexible)channel with wall properties and heat transfer is analyzed. Long wavelength and low Reynolds number approximations are considered. Analytical solution for velocity, stream function and temperature in terms of various physical parameters is obtained. The impact of yield stress, elasticity, slip and non-uniformity parameters on the peristaltic flow of Casson liquidare observed through graphs and discussed. The important outcome is that an increase in rigidity, stiffness and viscous damping force of the wall results in the enhancement of the size and number of bolus formed in the flow pattern.

Open access

Abdul Rauf Nizami, Afshan Perveen, Waqas Nazeer and Mahnoor Baqir

Abstract

In this paper we introduce the walk polynomial to find the number of walks of different lengths in a simple connected graph. We also give the walk polynomial of the bipartite, star, wheel, and gear graphs in closed forms.

Open access

A. Cantero, F. Crespo and S. Ferrer

Abstract

We study the roto-orbital dynamics of a uniform sphere and a triaxial body by means of a radial intermediary, which defines a 2-DOF Hamiltonian system. Our analysis is carried out by using variables referred to the total angular momentum. Its validity and applicability is assessed numerically by experiments comprising three different scenarios; analysis of the triaxiality, eccentricity and altitude. They show that there is a range of parameters and initial conditions for which the radial distance and the slow angles are estimated accurately, even after one orbital period. On the contrary, fast angles deteriorates as the triaxiality grows. We also include the study of the relative equilibria, finding constant radius solutions filling 4-D and lower dimensional tori. These families of relative equilibria include some of the classical ones reported in the literature and some new types. For a number of scenarios the relation between the triaxiality and the inclination connected with relative equilibria are given.

Open access

Chaudry Masood Khalique and Isaiah Elvis Mhlanga

Abstract

In this paper we study a (2+1)-dimensional coupling system with the Korteweg-de Vries equation, which is associated with non-semisimple matrix Lie algebras. Its Lax-pair and bi-Hamiltonian formulation were obtained and presented in the literature. We utilize Lie symmetry analysis along with the (G′/G)–expansion method to obtain travelling wave solutions of this system. Furthermore, conservation laws are constructed using the multiplier method.

Open access

Màrius Josep Fullana i Alfonso, Diego Pascual Sáez Milán, Josep Vicent Arnau i Córdoba and Neus Puchades Colmenero

Abstract

We make some considerations about Relativistic Positioning Systems (RPS). Four satellites are needed to position a user. First of all we define the main concepts. Errors should be taken into account. Errors depend on the Jacobian transformation matrix. Its Jacobian is proportional to the tetrahedron volume whose vertexes are the four tips of the receiver-satellite unit vectors. If the four satellites are seen by the user on a circumference in the sky, then, the Jacobian and the tetrahedron volume vanish. The users we consider are spacecraft. Spacecraft to be positioned cannot be close to a null Jacobian satellites-user configuration. These regions have to be avoided choosing an appropriate set of four satellites which are not seen too close to the same circumference in the sky. Errors also increase as the user spacecraft separates from the emission satellite region, since the tetrahedron volume decreases.We propose a method to autonomously potion a user-spacecraft which can test our method. This positioning should be compared with those obtained by current methods. Finally, a proposal to position a user-spacecraft moving far from Earth, with suitable devices (autonomous), is presented.

Open access

Yong Qin, Yuyan Luo, Jingru Lu, Lu Yin and Xinran Yu

Abstract

Resources and the environment have always been the two important natural factors that affect people’s lives. In recent years, the problem of resources and the environment has increasingly become an important issue that people are concerned about. This study discusses the use and consumption of energy and the impact of environmental pollution on economic development under sustainable economic development. This paper takes Panzhihua as an example to analyze the impact of energy and environment on the economy, and proposes solutions to improve economic development, which is of strategic significance for the future development of Panzhihua City. In this paper, the system dynamics method is used to decompose the Panzhihua large-scale system into three parts and carry out modeling and simulation to explore the connection between them. Based on the data from 2007 to 2015 in Panzhihua City, simulations have been carried out to obtain qualitative and quantitative analysis of certain simulation curves of the energy-environment-economy 3E system (hereinafter referred to as 3E system) from 2007 to 2030 to ascertain the future development pattern of Panzhihua City. The results show that when the 3E system is a coordinated development model, economic development and environmental protection have a good development trend at the same time, which is applicable to the future development of Panzhihua City. This model has good reference suggestions and application prospects for urban development. We want to give Panzhihua City the following suggestions: (1) Continue to focus on the secondary industry and increase competitiveness. (2) Increase the investment funds in environmental protection and achieve sustainable economic development.

Open access

Abdul Qudair Baig, Muhammad Naeem and Wei Gao

Abstract

Let G be a connected graph with vertex set V(G) and edge set E(G). Recently, the Revan vertex degree concept is defined in Chemical Graph Theory. The first and second Revan indices of G are defined as R 1(G) = uvE[rG(u) + rG(v)] and R 2(G) = uvE[rG(u)rG(v)], where uv means that the vertex u and edge v are adjacent in G. The first and second hyper-Revan indices of G are defined as HR 1(G) = uvE[rG(u) + rG(v)]2 and HR 2(G) = uvE[rG(u)rG(v)]2. In this paper, we compute the first and second kind of Revan and hyper-Revan indices for the octahedral and icosahedral networks.