Pre-multisymplectic constraint algorithm for field theories

We present a geometric algorithm for obtaining consistent solutions to systems of partial differential equations, mainly arising from singular covariant first-order classical field theories. This algorithm gives an intrinsic description of all the constraint submanifolds. The field equations are stated geometrically, either representing their solutions by integrable connections or, what is equivalent, by certain kinds of integrable m-vector fields. First, we consider the problem of finding connections or multivector fields solutions to the field equations in a general framework: a pre-multisymplectic fibre bundle (which will be identified with the first-order jet bundle and the multimomentum bundle when Lagrangian and Hamiltonian field theories are considered). Then, the problem is stated and solved in a linear context, and a pointwise application of the results leads to the algorithm for the general case. In a second step, the integrability of the solutions is also studied. Finally, the method is applied to Lagrangian and Hamiltonian field theories and, for the former, the problem of finding holonomic solutions is also analized.Comment: 30 pp. Presented in the International Workshop on Geometric Methods in Modern Physics (Firenze, April 2005

Constraint algorithm for k-presymplectic Hamiltonian systems. Application to singular field theories

The k-symplectic formulation of field theories is especially simple, since only tangent and cotangent bundles are needed in its description. Its defining elements show a close relationship with those in the symplectic formulation of mechanics. It will be shown that this relationship also stands in the presymplectic case. In a natural way, one can mimick the presymplectic constraint algorithm to obtain a constraint algorithm that can be applied to $k$-presymplectic field theory, and more particularly to the Lagrangian and Hamiltonian formulations of field theories defined by a singular Lagrangian, as well as to the unified Lagrangian-Hamiltonian formalism (Skinner--Rusk formalism) for k-presymplectic field theory. Two examples of application of the algorithm are also analyzed.Comment: 22 p

Mathematical models for immunology:current state of the art and future research directions

The advances in genetics and biochemistry that have taken place over the last 10 years led to significant advances in experimental and clinical immunology. In turn, this has led to the development of new mathematical models to investigate qualitatively and quantitatively various open questions in immunology. In this study we present a review of some research areas in mathematical immunology that evolved over the last 10 years. To this end, we take a step-by-step approach in discussing a range of models derived to study the dynamics of both the innate and immune responses at the molecular, cellular and tissue scales. To emphasise the use of mathematics in modelling in this area, we also review some of the mathematical tools used to investigate these models. Finally, we discuss some future trends in both experimental immunology and mathematical immunology for the upcoming years

PERCEPTIONS DES FEMMES ACCOUCHEES SUR L’ACCOUCHEMENT A DOMICILE DANS LA VILLE DE LUBUMBASHI: Cas de la Commune de Kampemba, Quartier Bongonga 2021

CONTEXT  Home births remain a global concern. Despite efforts to ban them, they are frequent and continue to claim many victims (3) the objectives of this study are to describe the socio-demographic profile, assess their knowledge of the risks, their perceptions, and determine the factors favoring home births in the Bongonga district. METHOD:  A qualitative study of phenomenological approach was  made for a period of one month on a population made up of women who gave birth at home. The data collection makes semi-structured interviews from an interview guide; data entered and encoded on Word, the analysis is the subject of an audition and transcription in theme. Then proceed to group the units of significance. By confronting similarities and contradictions, in order to identify free and imaginary variation and then achieve triangulation. RESULTS On 13 interview of women the result shows that the age of the women interviewed was 30 years old varying up to 43 years old. 6 out of 13 had given birth once at home; 4 out of 13 had given birth twice; 3 out of 13 had given birth 3 times at home. Their socio-demographic profile shows that 11 out of 13 were married, the major factors being the lack of money, occupation and the negligence of the care providers. CONCLUSION: The results of the qualitative study of phenomenological approach on home births is a real problem and women need help. However, they have a negative perception and remain optimistic about the resolution of the problem. Reproductive authorities needed to find lasting solutions to this situation.  CONTEXT  Home births remain a global concern. Despite efforts to ban them, they are frequent and continue to claim many victims (3) the objectives of this study are to describe the socio-demographic profile, assess their knowledge of the risks, their perceptions, and determine the factors favoring home births in the Bongonga district. METHOD:  A qualitative study of phenomenological approach was  made for a period of one month on a population made up of women who gave birth at home. The data collection makes semi-structured interviews from an interview guide; data entered and encoded on Word, the analysis is the subject of an audition and transcription in theme. Then proceed to group the units of significance. By confronting similarities and contradictions, in order to identify free and imaginary variation and then achieve triangulation. RESULTS On 13 interview of women the result shows that the age of the women interviewed was 30 years old varying up to 43 years old. 6 out of 13 had given birth once at home; 4 out of 13 had given birth twice; 3 out of 13 had given birth 3 times at home. Their socio-demographic profile shows that 11 out of 13 were married, the major factors being the lack of money, occupation and the negligence of the care providers. CONCLUSION: The results of the qualitative study of phenomenological approach on home births is a real problem and women need help. However, they have a negative perception and remain optimistic about the resolution of the problem. Reproductive authorities needed to find lasting solutions to this situation. &nbsp

Lead Speciation in the Dusts Emitted from Non-Ferrous Metallurgy Processes

The paper presents results for the speciation analysis of lead in dusts derived from dedusting of technological gasses from metallurgical processes of non-ferrous metals with different elementary content, made in accordance with two equal sequential extractions. Analytical procedure A provided possibilities for determination of fraction of Pb2+, metallic lead and fraction containing mainly lead sulfides. The second procedure (procedure B) was sequential extraction in accordance with Tessier. The results obtained in accordance with procedure A indicate that, regardless of the dust origin, the dominant group of Pb compounds is composed of lead salts which are soluble under alkaline conditions or lead compounds that form plumbites in the reaction with NaOH

Hearing nature’s heartbeat: towards large-scale real-time forest monitoring network in Italy

Climate change undermines forests’ health, vitality, and, as a consequence, tree functionality, productivity, and resilience to biotic disturbances. Mountain and sub-alpine forests are particularly susceptible to climate extremes and are showing signs of degradation in Europe. Warmer temperatures, drought, higher frequency and intensity of natural disturbances increasingly alter species distribution and survival, their growing capacity, reproduction, establishment, as well as their potential adaptation to climate change. Real-time monitoring of trees’ and stands’ responses to such events provides an effective way to better understand and even foresee the adverse side effects of climate change. The use of advanced and innovative monitoring tools and devices is required for ensuring long-term, large-scale, and real-time monitoring of forest dynamics. Here, we present the TreeTalker Italia Network (TTIN), i.e., the first large-scale network of tree-proximal sensors (TreeTalkers©) at a national scale in Italy. We describe the recent advances, innovations, and potential of such devices for continuous monitoring and research. As a primer, we argue that TTIN will provide effective support to ongoing science and policy efforts for monitoring natural resources’ dynamics on a large scale (e.g., forest inventory, climate impacts), including their effects on human well-being

Acúmulo e formas de cobre e zinco no solo após aplicações sucessivas de dejeto líquido de suínos

As aplicações sucessivas de dejeto líquido de suínos no solo podem aumentar os teores e alterar as formas de Cu e Zn no solo. O presente trabalho teve como objetivo estimar o acúmulo de Cu e Zn e suas formas em solo submetido a aplicações sucessivas de dejeto líquido de suínos, em sistema plantio direto com rotação de culturas. O trabalho foi desenvolvido em um Argissolo Vermelho distrófico arênico na área experimental do Departamento de Engenharia Agrícola da Universidade Federal de Santa Maria (RS). Os tratamentos consistiram na aplicação de 0, 20, 40 e 80 m³ ha-1 de dejeto líquido de suínos. Foram realizadas 17 aplicações de dejetos de maio de 2000 até o momento da coleta do solo, em outubro de 2006. Amostras de solo foram coletadas nas camadas de 0-2, 2-4, 4-6, 6-8, 8-10, 10-12, 12-14, 14-16, 16-18, 18-20, 20-25, 25-30, 30-35, 35-40, 40-50 e 50-60 cm, secas ao ar, passadas em peneiras de 2 mm e moídas em grau de ágata. Em seguida, foram preparadas e analisados os teores pseudototais após extração pelo método 3050B da EPA, disponíveis por meio da extração com HCl 0,1 mol L-1, além do fracionamento químico do Cu e do Zn. Nos dejetos de suínos foram determinados os teores pseudototais de Cu e Zn. As aplicações sucessivas de dejeto líquido de suínos no solo aumentaram os teores de Cu e Zn das camadas superficiais, com migração até 12 e 10 cm de profundidade, respectivamente. O Cu e Zn adicionados são acumulados no solo em formas biodisponíveis, sendo preferencialmente ligados às frações orgânica e mineral, respectivamente.Successive applications of pig slurry in the soil can increase the levels and change the forms of copper (Cu) and zinc (Zn). The objective of this study was to evaluate Cu and Zn accumulation and forms in the soil of areas with successive pig slurry applications under no tillage crop rotation. The experiment was carried out in a Typic Hapludalf in the experimental area of the Department of Agricultural Engineering of the Federal University of Santa Maria, Santa Maria (RS), Brazil. Pig slurry was applied at rates of 0, 20, 40 and 80 m³ ha-1. A total of 17 applications were applied to the soil surface between May 2000 and October 2006. The soil samples were collected in the layers 0-2, 2-4, 4-6, 6-8, 8-10, 10-12, 12-14, 14-16, 16-18, 18-20, 20-25, 25-30, 30-35, 35-40, 40-50, and 50-60 cm. The soil was dried, ground, sieved (2 mm) and the pseudo-total levels, available (HCl 0.1 mol L-1) and chemical fractions of Cu and Zn were determined. The pseudo-total contents of copper and zinc in the slurry were analyzed. Successive applications of pig slurry increased the pseudo-total content of copper and zinc in soil (surface layers), with migration to 12 and 10 cm depths, respectively. The Cu and Zn applied were accumulated in the soil in bioavailable forms, and preferentially associated with the organic and mineral fraction, respectively

Venous spread of renal cell carcinoma: MDCT

BACKGROUND: The purpose of our study was to present multidetector computed tomography (MDCT) findings in venous spread of renal cell carcinoma (RCC), to determine the superior extent of tumor thrombus and to compare MDCT findings with surgical report. ----- METHODS: The prospective MDCT study was performed on 31 patients diagnosed with RCC with venous spread (19 males and 12 females; age range 39-80 years; mean age 62.6 years). CT scans were obtained by MDCT scanner, in triphasic scanning protocol. All postprocessing techniques were performed by two independent radiologists, and the findings were reported in their consensus. MDCT diagnosis was compared with surgical and pathohistological findings. ----- RESULTS: Tumor thrombus extension into renal vein only (T3b stage) was found in 13/31 (42%) patients. Involvement of infradiaphragmatic level of inferior vena cava (IVC) (T3c stage) was found in 14/31 (45%) patients and supradiaphragmatic level of IVC (T4b stage) in 4/31 (13%) patients. In 27/31 (87%) patients surgery was performed, while 4/31 (13%) could not undergo surgery. In comparison with surgical report, in 25/27 (93%) operated patients the upper extent of the tumor thrombus was correctly diagnosed by MDCT, and 2/27 (7%) patients were falsely diagnosed. ----- CONCLUSION: MDCT represents a fast, relatively inexpensive, and reliable diagnostic method for evaluating the venous spread of RCC as well as the level of its upper extent. Triphasic MDCT is often the only diagnostic method necessary for planning the surgical procedure. Surgery should be performed as soon as possible for MDCT findings to be valid