Del mineral al frontal romànic: aplicació dels pigments minerals en pintura romànica al Berguedà

Treball de recerca realitzat per una alumna d’ensenyament secundari i guardonat amb un Premi CIRIT per fomentar l'esperit científic del Jovent l’any 2008. L’objectiu principal ha estat fer una reproducció a escala d’un frontal del romànic berguedà emprant pigments minerals. Sobre la base d’una recerca bibliogràfica exhaustiva, s’ha realitzat primer una aproximació teòrica amb l’objectiu de poder estudiar els pigments minerals des de diversos punts de vista: el científic, explicant la física, química i geologia del color; i l’artístic, explicant l’evolució dels pigments al llarg de la història de l’art –especialment en el Romànic català -. Paral•lelament, els estudis experimentals es van estructurar en quatre apartats: localització i recol•lecció de minerals, obtenció del pigment, elaboració de la pintura i reproducció del frontal romànic de Sant Andreu de Sagàs. Per tal de comprendre millor el procediment d’elaboració del frontal se’n va confeccionar un altre que es va dividir en quatre parts, corresponents als diferents passos que s’havien de seguir. El treball realitzat mostra que les dues grans branques del saber, l’art i la ciència, es troben íntimament relacionades. A més ha demostrat que gran part dels pigments que s’utilitzaven per elaborar les pintures romàniques del Berguedà provenien de l’entorn més directe, però en cas necessari s’utilitzaven minerals importats de terres llunyanes, com el cinabri. Les pintures elaborades amb pigments minerals tenen un alt valor afegit, ja que requereixen tot un procés de preparació molt llarg i laboriós.

Recuento de células progenitoras endoteliales en pacientes con ictus tratados previamente con estatinas

Estudio prospectivo de pacientes con ictus isquémico agudo cuyo objetivo es estudiar la influencia del tratamiento con estatinas sobre el recuento plasmático de Células Progenitoras Endoteliales (CPEs) determinadas por citometría de flujo. Se incluyeron 131 pacientes, el 32.1% pre-tratados con estatinas. El recuento de CPEs fue superior en los pacientes pre-tratados en el momento basal (p=0.015) y a los 7 días (p=0.029), pero equivalente a los 3 meses (p=0.49). El pre-tratamiento con estatinas se asocia a mayor recuento de CPEs en fase aguda y subaguda del infarto, sugiriendo un posible efecto reparador endotelial de las estatinas en la isquemia cerebral.

Tractament amb EPOCH a dosi ajustada i Rituximab en pacients no tractats amb LNH-B de cèl.lula gran de mal pronòstic

Aquest estudi multicèntric, fase IV analitza l’eficàcia i la seguretat del tractament amb dosi ajustada d’EPOCH amb Rituximab en infusió continua, en pacients no tractats prèviament amb mal pronòstic diagnosticats de limfomes B de cèl.lula gran. Material i mètodes. S’inclogueren 81 pacients, 68 d’aquests diagnosticats de Limfoma B difús de cèl.lula gran, 7 de Limfoma fol.licular grau III i 6 de Limfoma B primari de mediastí. Eren pacients de mal pronòstic segons IPI≥2 o IPIae≥1, ECOG/PS 0-4, estadi II-IV (estadi I si malaltia voluminosa al diagnòstic). Resultats. La edat mitjana era de 52 anys (rang, 21-77 anys), 92,5% d’alt risc segons l’IPIae. Es va obtenir resposta completa (RC i RCi) en el 79% dels pacients, la supervivència global i la supervivència lliure d’esdeveniment, a la mediana del temps de seguiment (34,3 mesos) va ser de 68% i 63,2%, respectivament. La supervivència lliure de malaltia als 5 anys va ser de 72,2% pels pacients que van assolir RC/RCi. Cap dels factors de risc de l’IPI o IPIae, ni els índexs per ells mateixos van resultar amb associació estadísticament significativa a la OS o PFS. Només es va obtenir associació entre els nivells de ß2 microglobulina (&3,5mg/l) i la PFS i OS (p=0,075 i p=0,015, respectivament). Es van reportar 54 episodis de neutropènia febril (11,5% dels cicles); i es van morir 27 pacients, 15 (55,5%) degut a progressió de la malaltia i 9 (33,3%) degut a sepsi o infecció grau 4. Conclusions. Els resultats aconseguits amb la combinació de Rituximab i DA-EPOCH mostren uns resultats prometedors i amb nivells de toxicitat molt acceptables en els pacients d’alt risc diagnosticats de Limfomes B de cèl.lula gran no tractats prèviament.

Impedance boundary conditions for pseudo-spectral time-domain methods in room acoustics

The Pseudo-Spectral Time Domain (PSTD) method is an alternative time-marching method to classical leapfrog finite difference schemes inthe simulation of wave-like propagating phenomena. It is based on the fundamentals of the Fourier transform to compute the spatial derivativesof hyperbolic differential equations. Therefore, it results in an isotropic operator that can be implemented in an efficient way for room acousticssimulations. However, one of the first issues to be solved consists on modeling wall absorption. Unfortunately, there are no references in thetechnical literature concerning to that problem. In this paper, assuming real and constant locally reacting impedances, several proposals toovercome this problem are presented, validated and compared to analytical solutions in different scenarios.

Precision determination of r(0)Lambda((MS)over-bar) from the QCD static energy

We use the recently obtained theoretical expression for the complete QCD static energy at next-to-next-to-next-to leading-logarithmic accuracy to determine r(0)Lambda((MS) over bar) by comparison with available lattice data, where r(0) is the lattice scale and Lambda((MS) over bar) is the QCD scale. We obtain r(0)Lambda((MS) over bar) = 0.622(-0.015)(+0.019) for the zero-flavor case. The procedure we describe can be directly used to obtain r(0)Lambda((MS) over bar) in the unquenched case, when unquenched lattice data for the static energy at short distances becomes available. Using the value of the strong coupling alpha(s) as an input, the unquenched result would provide a determination of the lattice scale r(0).

¿Favorece la publicación en abierto el impacto de los artículos científicos? Un estudio empírico en el ámbito de la medicina intensiva

Peer-reviewed

Presencia en Valencia de Rhizoecus cacticans (Hambl.) (Homoptera, pseudococcidae)

En el presente artículo se advierte de la presencia del pseudococcino Rhizoecus cacticans (HAMBLETON) en la zona de Valencia, atacando a raíces de cactáceas. Se dan algunas características del género y se describe la especie, así como algunos datos sobre los daños que causa. Se indican procedimientos posibles de control.

Buccodental health and oral mucositis. Clinical study in patients with hematological diseases

Objectives: The objective of the present study is to assess whether a good buccodental status (evaluated by means of dentogingival indices), is associated with a lower incidence and severity of oral mucositis in patients with hematological diseases who receive treatment with chemotherapy or bone marrow transplant. Study design: The study was carried out on 97 patients admitted to the Hematology Service of the Hospital Duran y Reynals in Barcelona during 2002-2003. These patients received treatment with chemotherapy or conditioning prior to bone marrow transplant. A descriptive study was made, analyzing oral hygiene, one dental index, and two gingivales indices, and evaluating their relationship with the appearance of mucositis. Results: The patients with high plaque (PI) and gingival (GI) indices during chemotherapy presented a higher percentage of mucositis (77.4% and 65.7% respectively) against those who had little or no visible plaque. In the case of the PI, the differences were statistically significant (p=0.015). Likewise, patients who brushed their teeth 3 times/day presented mucositis in only 26.7% of cases, against those who did not brush, or brushed only once a day (65.9% and 68.4%), these differences also being statistically significant (p=0.013). The CAO showed similar results in patients with or without mucositis (7.59 and 7.03 respectively). Conclusions: In our study, a good gingival status as well as good oral hygiene during chemoradiotherapy is associated with a lower incidence and severity of mucositis.

Attitudes and burden in relatives of patients with schizophrenia in a middle income country

BACKGROUND: Most studies of family attitudes and burden have been conducted in developed countries. Thus it is important to test the generalizability of this research in other contexts where social conditions and extended family involvement may be different. The aim of this study was to assess the relationship between the attitudes of caregivers and the burden they experience in such a context, namely Arica, a town located in the northernmost region of Chile, close to the border with Peru and Bolivia. METHODS: We assessed attitudes towards schizophrenia (including affective, cognitive and behavioural components) and burden (including subjective distress, rejection and competence) in 41 main caregivers of patients with schizophrenia, all of whom were users of Public Mental Health Services in Arica. RESULTS: Attitude measures differed significantly according to socio-demographic variables, with parents (mainly mothers) exhibiting a more negative attitude towards the environment than the rest of the family (t = 4.04; p = 0.000).This was also the case for caregivers with a low educational level (t = 3.27; p < 0.003), for the oldest caregivers (r = 0.546; p = 0.000) and for those who had spent more time with the patient (r = 0.377; p = 0.015). Although attitudes had significant association with burden, their explanatory power was modest (R2 = .104, F = 4,55; p = .039). CONCLUSIONS: Similar to finding developed countries, the current study revealed a positive and significant relationship between the attitudes of caregivers and their burden. These findings emphasize the need to support the families of patients with schizophrenia in this social context.

High Prevalence of Signs of Renal Damage Despite Normal Renal Function in a Cohort of HIV-Infected Patients: Evaluation of Associated Factors

Renal disorders are an emerging problem in HIV-infected patients. We performed a cross-sectional study of the first 1000 HIV-infected patients attended at our HIV unit who agreed to participate. We determined the frequency of renal alterations and its related risk factors. Summary statistics and logistic regression were applied. The study sample comprised 970 patients with complete data. Most were white (94%) and men (76%). Median (IQR) age was 48 (42–53) years. Hypertension was diagnosed in 19%, dyslipidemia in 27%, and diabetes mellitus in 3%. According to the Chronic Kidney Disease Epidemiology Collaboration (CKD EPI) equation, 29 patients (3%) had an eGFR < 60 ml/min/1.73m2; 18 of them (62%) presented altered albumin/creatinine and protein/creatinine (UPC or UAC) ratios. Of the patients with eGFR> 60mL/min, it was present in 293 (30%), 38 of whom (7.1%) had UPC> 300mg/g. Increased risk of renal abnormalities was correlated with hypertension (OR, 1.821 [95%CI, 1.292;2.564]; p = 0.001), age (OR, 1.015 [95%CI, 1.001;1.030], per one year; p = 0.040), and use of tenofovir disoproxil fumarate (TDF) plus protease inhibitor (PI), (OR, 1.401 [95%CI, 1.078;1.821]; p = 0.012). Current CD4 cell count was a protective factor (OR, 0.9995 [95%CI, 0.9991;0.9999], per one cell; p = 0.035). A considerable proportion of patients presented altered UPC or UAC ratios, despite having an eGFR > 60mL/min. CD4 cell count was a protective factor; age, hypertension, and use of TDF plus PIs were risk factors for renal abnormalities. Based on our results, screen of renal abnormalities should be considered in all HIV-infected patients to detect these alterations early.

New approximation to the third-order density : application to the calculation of correlated multicenter indices

In this work we present the formulas for the calculation of exact three-center electron sharing indices (3c-ESI) and introduce two new approximate expressions for correlated wave functions. The 3c-ESI uses the third-order density, the diagonal of the third-order reduced density matrix, but the approximations suggested in this work only involve natural orbitals and occupancies. In addition, the first calculations of 3c-ESI using Valdemoro's, Nakatsuji's and Mazziotti's approximation for the third-order reduced density matrix are also presented for comparison. Our results on a test set of molecules, including 32 3c-ESI values, prove that the new approximation based on the cubic root of natural occupancies performs the best, yielding absolute errors below 0.07 and an average absolute error of 0.015. Furthemore, this approximation seems to be rather insensitive to the amount of electron correlation present in the system. This newly developed methodology provides a computational inexpensive method to calculate 3c-ESI from correlated wave functions and opens new avenues to approximate high-order reduced density matrices in other contexts, such as the contracted Schrödinger equation and the anti-Hermitian contracted Schrödinger equation